Radical protection in the visible and infrared by a hyperforin-rich cream--in vivo versus ex vivo methods.

PubMed

Arndt, Sophia; Haag, Stefan F; Kleemann, Anke; Lademann, Juergen; Meinke, Martina C

2013-05-01

The formation of radicals plays an important role in the development of atopic eczema or barrier-disrupted skin. We evaluated the radical scavenging effect of a cream containing a Hypericum perforatum extract rich in hyperforin in a double-blind placebo-controlled study on 11 healthy volunteers. Electron paramagnetic resonance spectroscopy was applied to determine radical formation during VIS/NIR irradiation of the inner forearm. The results were compared to ex vivo investigations on excised porcine ear skin after a single application of the creams. The non-treated skin was measured as control. The absolute values and the kinetics are not comparable for ex vivo and in vivo radical formation. Whereas in vivo, the radical production decreases with time, it remains stable ex vivo over the investigated timescale. Nevertheless, ex vivo methods could be developed to estimate the protection efficiency of creams. In vivo as well as ex vivo, the radical formation could be reduced by almost 80% when applying the hyperforin-rich cream onto the skin, whereas placebo resulted in about 60%. In vivo, a daylong protection effect could be validated after a 4-week application time of the cream indicating that a regular application is necessary to obtain the full effect. © 2013 John Wiley & Sons A/S.

Virtual reality treatment versus exposure in vivo: a comparative evaluation in acrophobia.

PubMed

Emmelkamp, P M G; Krijn, M; Hulsbosch, A M; de Vries, S; Schuemie, M J; van der Mast, C A P G

2002-05-01

The aim of the present study was to evaluate the effectiveness of low-budget virtual reality (VR) exposure versus exposure in vivo in a between-group design in 33 patients suffering from acrophobia. The virtual environments used in treatment were exactly copied from the real environments used in the exposure in vivo program. VR exposure was found to be as effective as exposure in vivo on anxiety and avoidance as measured with the Acrophobia Questionnaire (AQ), the Attitude Towards Heights Questionnaire (ATHQ) and the Behavioral Avoidance Test (BAT). Results were maintained up to six months follow-up. The present study shows that VR exposure can be effective with relatively cheap hardware and software on stand-alone computers currently on the market. Further studies into the effectiveness of VR exposure are recommended in other clinical groups as agoraphobics and social phobics and studies in which VR exposure is compared with more emerging virtual worlds as presented in CAVE-type systems.

Comparative in vivo mucoadhesion studies of thiomer formulations using magnetic resonance imaging and fluorescence detection.

PubMed

Albrecht, K; Greindl, M; Kremser, C; Wolf, C; Debbage, P; Bernkop-Schnürch, A

2006-09-28

The aim of this study was to compare different oral delivery systems based on the thiolated polymer polycarbophil-cysteine (PCP-Cys) and to provide evidence for the validity of the hypothesis that unhydrated polymers provide better mucoadhesion in vivo. To achieve dry polymer application, a new, experimental dosage form named Eutex (made of Eudragit L100-55 and latex) capsule has been developed. Magnetic resonance imaging was used to localize the point of release of the thiolated polymer from the application forms via the positive magnetic resonance signal from a gadolinium complex (Gd-DTPA). In vivo mucoadhesion was determined by ascertaining the residence time of the fluorescence-tagged thiomer on intestinal mucosa after 3 h. Results showed that in comparison to conventional application forms the Eutex capsules led to 1.9-fold higher mucoadhesive properties of PCP-Cys when compared to application with a conventional enteric-coated capsule, and to 1.4-fold higher mucoadhesion when compared to administration with an enteric-coated tablet of the thiomer. The findings of this study should contribute to the understanding of mucoadhesion and mucoadhesion influencing parameters in vivo and should therefore be of considerable interest for the development of future mucoadhesive oral drug delivery dosage forms.

Evaluation of a reproduction technique for the study of the enamel composite/bracket base area.

PubMed

Wilner, F J; Oliver, R G

2000-09-01

The objective of the study was to evaluate a reproduction method that would enable the study of the enamel/ bracket/composite interface in vivo, and consisted of in vitro assessment of two different impression materials to compare reproduction of brackets bonded to extracted teeth followed by in vivo assessment of the superior material. In vitro standard edgewise brackets were bonded to two extracted teeth and impressions were taken using two different types of low viscosity silicone-based impression materials. A medium viscosity silicone impression material was used to support the original impression. Three impressions of both the gingival and occlusal aspect of the bracket base region were obtained using each of the impression materials. Replicas were then prepared for SEM viewing and these compared to SEMs of the real teeth for reproduction of detail. A 3-point Reproducibility Index was used to compare the SEM photographs of the comparable replicas. One impression material was clearly superior to the other and produced an acceptably accurate representation of the true clinical situation in three out of four samples. This material also performed well in the in vivo situation. The technique described is satisfactory for the production and analysis of SEM pictures of the enamel/composite/ bracket base interface in vivo.

A prospective, observational study comparing the PK/PD relationships of generic Meropenem (Mercide®) to the innovator brand in critically ill patients.

PubMed

Mer, Mervyn; Snyman, Jacques Rene; van Rensburg, Constance Elizabeth Jansen; van Tonder, Jacob John; Laurens, Ilze

2016-01-01

Clinicians' skepticism, fueled by evidence of inferiority of some multisource generic antimicrobial products, results in the underutilization of more cost-effective generics, especially in critically ill patients. The aim of this observational study was to demonstrate equivalence between the generic or comparator brand of meropenem (Mercide ® ) and the leading innovator brand (Meronem ® ) by means of an ex vivo technique whereby antimicrobial activity is used to estimate plasma concentration of the active moiety. Patients from different high care and intensive care units were recruited for observation when prescribed either of the meropenem brands under investigation. Blood samples were collected over 6 hours after a 30 minute infusion of the different brands. Meropenem concentration curves were established against United States Pharmacopeia standard meropenem (Sigma-Aldrich) by using standard laboratory techniques for culture of Klebsiella pneumoniae. Patients' plasma samples were tested ex vivo, using a disc diffusion assay, to confirm antimicrobial activity and estimate plasma concentrations of the two brands. Both brands of meropenem demonstrated similar curves in donor plasma when concentrations in vials were confirmed. Patient-specific serum concentrations were determined from zones of inhibition against a standard laboratory Klebsiella strain ex vivo, confirming at least similar in vivo concentrations as the concentration curves (90% confidence interval) overlapped; however, the upper limit of the area under the curve for the ratio comparator/innovator exceeded the 1.25-point estimate, i.e., 4% higher for comparator meropenem. This observational, in-practice study demonstrates similar ex vivo activity and in vivo plasma concentration time curves for the products under observation. Assay sensitivity is also confirmed. Current registration status of generic small molecules is in place. The products are therefore clinically interchangeable based on registration status as well as bioassay results, demonstrating sufficient overlap for clinical comfort. The slightly higher observed comparator meropenem concentration (4%) is still clinically acceptable due to the large therapeutic index and should ally fears of inferiority.

Descemet Membrane Thickening as a Sign for the Diagnosis of Corneal Graft Rejection: An Ex Vivo Study.

PubMed

VanDenBerg, Ryan; Diakonis, Vasilios F; Bozung, Alison; Gameiro, Gustavo Rosa; Fischer, Oliver; El Dakkak, Ahmed; Ulloa-Padilla, Jan Paul; Anagnostopoulos, Apostolos; Dubovy, Sander; Abou Shousha, Mohamed

2017-12-01

To disclose, using an ex vivo study, the histopathological mechanism behind in vivo thickening of the endothelium/Descemet membrane complex (En/DM) observed in rejected corneal grafts (RCGs). Descemet membrane (DM), endothelium, and retrocorneal membranes make up the total En/DM thickness. These layers are not differentiable by high-definition optical coherence tomography; therefore, the source of thickening is unclear from an in vivo perspective. A retrospective ex vivo study (from September 2015 to December 2015) was conducted to measure the thicknesses of DM, endothelium, and retrocorneal membrane in 54 corneal specimens (31 RCGs and 23 controls) using light microscopy. Controls were globes with posterior melanoma without corneal involvement. There were 54 corneas examined ex vivo with mean age 58.1 ± 12.2 in controls and 51.7 ± 27.9 years in RCGs. The ex vivo study uncovered the histopathological mechanism of En/DM thickening to be secondary to significant thickening (P < 0.001) of DM (6.5 ± 2.4 μm) in RCGs compared with controls (3.9 ± 1.5 μm). Our ex vivo study shows that DM is responsible for thickening of the En/DM in RCGs observed in vivo by high-definition optical coherence tomography and not the endothelium or retrocorneal membrane.

Forensic postmortem computed tomography: volumetric measurement of the heart and liver.

PubMed

Jakobsen, Lykke Schrøder; Lundemose, Sissel; Banner, Jytte; Lynnerup, Niels; Jacobsen, Christina

2016-12-01

The purpose of this study was to investigate the utility of postmortem computed tomography (PMCT) images in estimating organ sizes and to examine the use of the cardiothoracic ratio (CTR). We included 45 individuals (19 females), who underwent a medico-legal autopsy. Using the computer software program Mimics ® , we determined in situ heart and liver volumes derived from linear measurements (width, height and depth) on a whole body PMCT-scan, and compared the volumes with ex vivo volumes derived by CT-scan of the eviscerated heart and liver. The ex vivo volumes were also compared with the organ weights. Further, we compared the CTR with the ex vivo heart volume and a heart weight-ratio (HWR). Intra- and inter-observer analyses were performed. We found no correlation between the in situ and ex vivo volumes of the heart and liver. However, a highly significant correlation was found between the ex vivo volumes and weights of the heart and liver. No correlations between CTR and the ex vivo heart volume nor with HWR was found. Concerning cardiomegaly, we found no agreement between the CTR and HWR. The intra- and inter-observer analyses showed no significant differences. Noninvasive in situ PMCT methods for organ measuring, as performed in this study, are not useful tools in forensic pathology. The best method to estimate organ volume is a CT-scan of the eviscerated organ. PMCT-determined CTR seems to be useless for ascertaining cardiomegaly, as it neither correlated with the ex vivo heart volume nor with the HWR.

Are there subtle genome-wide epigenetic alterations in normal offspring conceived by assisted reproductive technologies?

PubMed

Batcheller, April; Cardozo, Eden; Maguire, Marcy; DeCherney, Alan H; Segars, James H

2011-12-01

To review recent data regarding subtle, but widespread, epigenetic alterations in phenotypically normal offspring conceived by assisted reproductive technologies (ART) compared with offspring conceived in vivo. A PubMed computer search was performed to identify relevant articles. Research institution. Not applicable. None. Not applicable. Studies in animals indicate that in vitro culture may be associated with widespread alterations in imprinted genes compared with in vivo-conceived offspring. Recently, studies in humans have likewise demonstrated widespread changes in DNA methylation, including genes linked to adipocyte development, insulin signaling, and obesity in offspring conceived by ART compared with in vivo-conceived children. Changes in multiple imprinted genes after ART also were noted in additional studies, which suggested that the diagnosis of infertility may explain the differences between in vivo-conceived and ART offspring. These data suggest that ART is associated with widespread epigenetic modifications in phenotypically normal children, and that these modifications may increase the risk of adverse cardiometabolic outcomes. Further research is needed to elucidate the possible relationship between ART, genome-wide alterations in imprinted genes, and their potential relevance to subtle cardiometabolic consequences reported in ART offspring. Published by Elsevier Inc.

Impact of CCL2 and CCR2 Chemokine / Receptor Deficiencies on Macrophage Recruitment and Continuous Glucose Monitoring in vivo

PubMed Central

Klueh, Ulrike; Czajkowski, Caroline; Ludzinska, Izabela; Qiao, Yi; Frailey, Jackman; Kreutzer, Donald L.

2016-01-01

The accumulation of macrophages (MΦ) at the sensor-tissue interface is thought to be a major player in controlling tissue reactions and sensor performance in vivo. Nevertheless until recently no direct demonstration of the causal relationship between MΦ aggregation and loss of sensor function existed. Using a Continuous Glucose Monitoring (CGM) murine model we previously demonstrated that genetic deficiencies of MΦ or depletion of MΦ decreased MΦ accumulation at sensor implantation sites, which led to significantly enhanced CGM performance, when compared to normal mice. Additional studies in our laboratories have also demonstrated that MΦ can act as “metabolic sinks” by depleting glucose levels at the implanted sensors in vitro and in vivo. In the present study we extended these observations by demonstrating that MΦ chemokine (CCL2) and receptor (CCR2) knockout mice displayed a decrease in inflammation and MΦ recruitment at sensor implantation sites, when compared to normal mice. This decreased MΦ recruitment significantly enhanced CGM performance when compared to control mice. These studies demonstrated the importance of the CCL2 family of chemokines and related receptors in MΦ recruitment and sensor performance and suggest chemokine targets for enhancing CGM in vivo. PMID:27376197

Hepatic radiofrequency ablation: in vivo and ex vivo comparisons of 15-gauge (G) and 17-G internally cooled electrodes

PubMed Central

Song, K D; Park, H J; Cha, D I; Kang, T W; Lee, J; Moon, J Y; Rhim, H

2015-01-01

Objective: To compare the performance of the 15-G internally cooled electrode with that of the conventional 17-G internally cooled electrode. Methods: A total of 40 (20 for each electrode) and 20 ablation zones (10 for each electrode) were made in extracted bovine livers and in in vivo porcine livers, respectively. Technical parameters, three dimensions [long-axis diameter (Dl), vertical-axis diameter (Dv) and short-axis diameter (Ds)], volume and the circularity (Ds/Dl) of the ablation zone were compared. Results: The total delivered energy was higher in the 15-G group than in the 17-G group in both ex vivo and in vivo studies (8.78 ± 1.06 vs 7.70 ± 0.98 kcal, p = 0.033; 11.20 ± 1.13 vs 8.49 ± 0.35 kcal, p = 0.001, respectively). The three dimensions of the ablation zone had a tendency to be larger in the 15-G group than in the 17-G group in both studies. The ablation volume was larger in the 15-G group than in the 17-G group in both ex vivo and in vivo studies (29.61 ± 7.10 vs 23.86 ± 3.82 cm3, p = 0.015; 10.26 ± 2.28 vs 7.79 ± 1.68 cm3, p = 0.028, respectively). The circularity of ablation zone was not significantly different in both the studies. Conclusion: The size of ablation zone was larger in the 15-G internally cooled electrode than in the 17-G electrode in both ex vivo and in vivo studies. Advances in knowledge: Radiofrequency ablation of hepatic tumours using 15-G electrode is useful to create larger ablation zones. PMID:25882688

In Vivo Biomolecule Corona around Blood-Circulating, Clinically Used and Antibody-Targeted Lipid Bilayer Nanoscale Vesicles.

PubMed

Hadjidemetriou, Marilena; Al-Ahmady, Zahraa; Mazza, Mariarosa; Collins, Richard F; Dawson, Kenneth; Kostarelos, Kostas

2015-08-25

The adsorption of proteins and their layering onto nanoparticle surfaces has been called the "protein corona". This dynamic process of protein adsorption has been extensively studied following in vitro incubation of many different nanoparticles with plasma proteins. However, the formation of protein corona under dynamic, in vivo conditions remains largely unexplored. Extrapolation of in vitro formed protein coronas to predict the fate and possible toxicological burden from nanoparticles in vivo is of great interest. However, complete lack of such direct comparisons for clinically used nanoparticles makes the study of in vitro and in vivo formed protein coronas of great importance. Our aim was to study the in vivo protein corona formed onto intravenously injected, clinically used liposomes, based on the composition of the PEGylated liposomal formulation that constitutes the anticancer agent Doxil. The formation of in vivo protein corona was determined after the recovery of the liposomes from the blood circulation of CD-1 mice 10 min postinjection. In comparison, in vitro protein corona was formed by the incubation of liposomes in CD-1 mouse plasma. In vivo and in vitro formed protein coronas were compared in terms of morphology, composition and cellular internalization. The protein coronas on bare (non-PEGylated) and monoclonal antibody (IgG) targeted liposomes of the same lipid composition were also comparatively investigated. A network of linear fibrillary structures constituted the in vitro formed protein corona, whereas the in vivo corona had a different morphology but did not appear to coat the liposome surface entirely. Even though the total amount of protein attached on circulating liposomes correlated with that observed from in vitro incubations, the variety of molecular species in the in vivo corona were considerably wider. Both in vitro and in vivo formed protein coronas were found to significantly reduce receptor binding and cellular internalization of antibody-conjugated liposomes; however, the in vivo corona formation did not lead to complete ablation of their targeting capability.

Voluntary chronic exercise augments in vivo natural immunity in rats.

PubMed

Jonsdottir, I H; Asea, A; Hoffmann, P; Dahlgren, U I; Andersson, B; Hellstrand, K; Thorén, P

1996-05-01

The effect of chronic voluntary exercise on the immune response was studied in spontaneously hypertensive rats. Exercise consisted of voluntary running in wheels for 5 wk, and the mean running distance was 4.2 km/24 h. In vivo cytotoxicity was measured as clearance of injected 51Cr-labeled YAC-1 lymphoma cells from the lungs. The clearance of YAC-1 cells in vivo was significantly increased in runners compared with sedentary controls (P < 0.001). The total number of mononuclear cells in the spleen was significantly decreased in runners compared with controls. Analysis of splenic lymphocyte phenotypes revealed a significantly increased fraction of OX52+/CD5- natural killer cells in runners compared with sedentary controls. In contrast to changes in natural immunity, immunoglobulins G and M levels in serum, the antibody response to antigen in vivo, and the proliferation of splenic T cells in vitro were unchanged. Our data suggest that chronic voluntary exercise augments natural cytotoxicity mechanisms in vivo, whereas splenic T-cell proliferation and the antibody-mediated immune response remain unchanged.

Liposomal-benzocaine gel formulation: correlation between in vitro assays and in vivo topical anesthesia in volunteers.

PubMed

Franz-Montan, Michelle; Cereda, Cintia Maria Saia; Gaspari, Adele; da Silva, Camila Morais Gonçalves; de Araújo, Daniele Ribeiro; Padula, Cristina; Santi, Patrizia; Narvaes, Eliene; Novaes, Pedro Duarte; Groppo, Francisco Carlos; de Paula, Eneida

2013-03-01

The aim of the present study was to characterize a liposome-based benzocaine (BZC) formulation designed for topical use on the oral mucosa and to evaluate its in vitro retention and permeation using the Franz-type diffusion cells through pig esophagus mucosa. To predict the effectiveness of new designed formulations during preclinical studies, a correlation between in vitro assays and in vivo efficacy was performed. Liposomal BZC was characterized in terms of membrane/water partition coefficient, encapsulation efficiency, size, polydispersity, zeta potential, and morphology. Liposomal BZC (BL10) was incorporated into gel formulation and its performances were compared to plain BZC gel (B10) and the commercially available BZC gel (B20). BL10 and B10 presented higher flux and retention on pig esophagus mucosa with a shorter lag time, when compared to B20. BZC flux was strongly correlated with in vivo anesthetic efficacy, but not with topical anesthesia duration. The retention studies did not correlate with any of the in vivo efficacy parameters. Thus, in vitro permeation study can be useful to predict anesthetic efficacy during preclinical tests, because a correlation between flux and anesthetic efficacy was observed. Therefore, in vitro assays, followed by in vivo efficacy, are necessary to confirm anesthetic performance.

In vivo and ex vivo characterization of a novel Er fiber laser system for fractional treatment of soft oral tissues

NASA Astrophysics Data System (ADS)

Shatilova, Ksenia; Aloian, Georgii; Karabut, Maria; Ryabova, Valentina; Yaroslavsky, Ilya V.; Altshuler, Gregory

2018-02-01

In this work, we present the first histological in vivo and ex vivo study of effects of fractional Er fiber laser (wavelength 1550 nm, peak power 25 W) on keratinized gum and alveolar mucosa for gum regeneration. Biopsy with subsequent NBTC staining was used as primary evaluation technique. Ex vivo, porcine tissue model was used. Effects of pulse energy, beam diameter, and beam divergence were investigated in detail. It has been demonstrated that under optimal conditions columns up to 800 μm in depth could be reliably produced with 130 mJ pulses. Clinically, 2 subjects were treated and 4 punch biopsies were collected. The results were compared with ex vivo data. Both ex vivo and in vivo datasets suggest feasibility of a dental fractional system intended for gum regeneration.

Comparison of in vivo toxicity, antioxidant and immunomodulatory activities of coconut, nipah and pineapple juice vinegars.

PubMed

Mohamad, Nurul Elyani; Keong Yeap, Swee; Beh, Boon Keen; Romli, Muhammad Firdaus; Yusof, Hamidah Mohd; Kristeen-Teo, Ye Wen; Sharifuddin, Shaiful Adzni; Long, Kamariah; Alitheen, Noorjahan Banu

2018-01-01

Vinegar is widely used as a food additive, in food preparation and as a food supplement. This study compared the phenolic acid profiles and in vivo toxicities, and antioxidant and immunomodulatory effects of coconut, nipah and pineapple juice vinegars, which were respectively prepared via a two-step fermentation using Saccharomyces cerevisiae 7013 INRA and Acetobacter aceti vat Europeans. Pineapple juice vinegar, which had the highest total phenolic acid content, also exhibited the greatest in vitro antioxidant capacity compared to coconut juice and nipah juice vinegars. Following acute and sub-chronic in vivo toxicity evaluation, no toxicity and mortality were evident and there were no significant differences in the serum biochemical profiles between mice administered the vinegars versus the control group. In the sub-chronic toxicity evaluation, the highest liver antioxidant levels were found in mice fed with pineapple juice vinegar, followed by coconut juice and nipah juice vinegars. However, compared to the pineapple juice and nipah juice vinegars, the mice fed with coconut juice vinegar, exhibited a higher population of CD4 + and CD8 + T-lymphocytes in the spleen, which was associated with greater levels of serum interleukin-2 and interferon-γ cytokines. Overall, the data suggested that not all vinegar samples cause acute and sub-chronic toxicity in vivo. Moreover, the in vivo immunity and organ antioxidant levels were enhanced, to varying extents, by the phenolic acids present in the vinegars. The results obtained in this study provide appropriate guidelines for further in vivo bioactivity studies and pre-clinical assessments of vinegar consumption. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Satellite DNA methylation status and expression of selected genes in Bos indicus blastocysts produced in vivo and in vitro.

PubMed

Urrego, R; Bernal-Ulloa, S M; Chavarría, N A; Herrera-Puerta, E; Lucas-Hahn, A; Herrmann, D; Winkler, S; Pache, D; Niemann, H; Rodriguez-Osorio, N

2017-04-01

Bovine embryos produced in vivo and in vitro differ with respect to molecular profiles, including epigenetic marks and gene expression profiles. This study investigated the CpG methylation status in bovine testis satellite I (BTS) and Bos taurus alpha satellite I (BTαS) DNA sequences, and concomitantly the relative abundance of transcripts, critically involved in DNA methylation (DNMT1 and DNMT3A), growth and development (IGF2R) and pluripotency (POU5F1) in Bos indicus embryos produced in vitro or in vivo. Results revealed that methylation of BTS were higher (P < 0.05) in embryos produced in vitro compared with their in vivo produced counterparts, while the methylation status of BTαS was similar in both groups. There were no significant differences in transcript abundance for DNMT3A, IGF2R and POU5F1 between blastocysts produced in vivo and in vitro. However, a significantly lower amount of DNMT1 transcripts was found in the in vitro cultured embryos (P < 0.05) compared with their in vivo derived counterparts. In conclusion, this study reported only minor changes in the expression of developmentally important genes and satellite DNA methylation related to the in vitro embryo production system.

A new bioluminescent reporter system to study the biodistribution of systematically injected tumor-derived bioluminescent extracellular vesicles in mice

PubMed Central

Gangadaran, Prakash; Li, Xiu Juan; Lee, Ho Won; Oh, Ji Min; Kalimuthu, Senthilkumar; Rajendran, Ramya Lakshmi; Son, Seung Hyun; Baek, Se Hwan; Singh, Thoudam Debraj; Zhu, Liya; Jeong, Shin Young; Lee, Sang-Woo; Lee, Jaetae; Ahn, Byeong-Cheol

2017-01-01

In vivo biodistribution and fate of extracellular vesicles (EVs) are still largely unknown and require reliable in vivo tracking techniques. In this study, in vivo bioluminescence imaging (BLI) using Renilla luciferase (Rluc) was developed and applied to monitoring of EVs derived from thyroid cancer (CAL-62 cells) and breast cancer (MDA-MB-231) in nude mice after intravenous administration and was compared with a dye-based labeling method for EV derived from CAL-62 cells. The EVs were successfully labeled with Rluc and visualized by BLI in mice. In vivo distribution of the EVs, as measured by BLI, was consistent with the results of ex vivo organ analysis. EV-CAL-62/Rluc showed strong signals at lung followed by liver, spleen & kidney (P < 0.05). EV-MDA-MB-231/Rluc showed strong signals at liver followed by lung, spleen & kidney (P < 0.05). EV-CAL-62/Rluc and EV-MDA-MB-231/Rluc stayed in animal till day 9 and 3, respectively; showed a differential distribution. Spontaneous EV-CAL-62/Rluc shown distributed mostly to lung followed by liver, spleen & kidney. The new BLI system used to show spontaneous distribution of EV-CAL-62/Rluc in subcutaneous CAL-62/Rluc bearing mice. Dye (DiR)-labeled EV-CAL-62/Rluc showed a different distribution in vivo & ex vivo compared to EV-CAL-62/Rluc. Fluorescent signals were predominately detected in the liver (P < 0.05) and spleen (P < 0.05) regions. The bioluminescent EVs developed in this study may be used for monitoring of EVs in vivo. This novel reporter-imaging approach to visualization of EVs in real time is expected to pave the way for monitoring of EVs in EV-based treatments. PMID:29299117

Development of novel formulations to enhance in vivo transdermal permeation of tocopherol.

PubMed

Nada, Aly H; Zaghloul, Abdelazim A; Hedaya, Mohsen M; Khattab, Ibrahim S

2014-09-01

Tocopherol represents a big challenge for transdermal permeation owing to its extreme hydrophobicity and large molecular mass. The aim of the present study was to develop alpha-tocopherol (T) topical formulations and evaluate their ex vivo and in vivo permeation. Franz diffusion cells were used for ex vivo permeation, and neonatal rats were used for in vivo permeation. Seven gel formulations and 21 liquid formulations were investigated for physical stability, viscosity and permeation of T. Analysis of T was performed by a validated HPLC method using a UV detector. The ex vivo permeation from gel and emulsion formulations was very poor (0.001-0.015%). Highest permeation was observed from monophasic liquid formulations containing dimethyl sulfoxide (DMSO), tocopheryl polyethylene glycols (TPGs), propylene glycol, ethanol and 9.5% T. The in vivo results demonstrated higher retention in the epidermis compared to subcutaneous tissues, 1377 and 1.13 μg g⁻¹, respectively. Increasing T concentration from 4.8 to 9.5% did not increase the amount permeated or % of T retained. It was concluded that simple solutions of T in the presence of DMSO and TPGs were more promising systems for effective transdermal permeation compared to gel, emulsion or oleaginous systems.

Algorithm optimization for multitined radiofrequency ablation: comparative study in ex vivo and in vivo bovine liver.

PubMed

Appelbaum, Liat; Sosna, Jacob; Pearson, Robert; Perez, Sarah; Nissenbaum, Yizhak; Mertyna, Pawel; Libson, Eugene; Goldberg, S Nahum

2010-02-01

To prospectively optimize multistep algorithms for largest available multitined radiofrequency (RF) electrode system in ex vivo and in vivo tissues, to determine best energy parameters to achieve large predictable target sizes of coagulation, and to compare these algorithms with manufacturer's recommended algorithms. Institutional animal care and use committee approval was obtained for the in vivo portion of this study. Ablation (n = 473) was performed in ex vivo bovine liver; final tine extension was 5-7 cm. Variables in stepped-deployment RF algorithm were interrogated and included initial current ramping to 105 degrees C (1 degrees C/0.5-5.0 sec), the number of sequential tine extensions (2-7 cm), and duration of application (4-12 minutes) for final two to three tine extensions. Optimal parameters to achieve 5-7 cm of coagulation were compared with recommended algorithms. Optimal settings for 5- and 6-cm final tine extensions were confirmed in in vivo perfused bovine liver (n = 14). Multivariate analysis of variance and/or paired t tests were used. Mean RF ablation zones of 5.1 cm +/- 0.2 (standard deviation), 6.3 cm +/- 0.4, and 7 cm +/- 0.3 were achieved with 5-, 6-, and 7-cm final tine extensions in a mean of 19.5 min +/- 0.5, 27.9 min +/- 6, and 37.1 min +/- 2.3, respectively, at optimal settings. With these algorithms, size of ablation at 6- and 7-cm tine extension significantly increased from mean of 5.4 cm +/- 0.4 and 6.1 cm +/- 0.6 (manufacturer's algorithms) (P <.05, both comparisons); two recommended tine extensions were eliminated. In vivo confirmation produced mean diameter in specified time: 5.5 cm +/- 0.4 in 18.5 min +/- 0.5 (5-cm extensions) and 5.7 cm +/- 0.2 in 21.2 min +/- 0.6 (6-cm extensions). Large zones of coagulation of 5-7 cm can be created with optimized RF algorithms that help reduce number of tine extensions compared with manufacturer's recommendations. Such algorithms are likely to facilitate the utility of these devices for RF ablation of focal tumors in clinical practice. (c) RSNA, 2010.

Plant Regeneration and Cellular Behaviour Studies in Celosia cristata Grown In Vivo and In Vitro

PubMed Central

Taha, Rosna Mat; Wafa, Sharifah Nurashikin

2012-01-01

Tissue culture studies of Celosia cristata were established from various explants and the effects of various hormones on morphogenesis of this species were examined. It was found that complete plant regeneration occurred at highest percentage on MS medium supplemented with 2.0 mg/L NAA and 1.5 mg/L BAP, with the best response showed by shoot explants. In vitro flowering was observed on MS basal medium after six weeks. The occurrence of somaclonal variation and changes in cellular behavior from in vivo and in vitro grown plants were investigated through cytological studies and image analysis. It was observed that Mitotic Index (MI), mean chromosome numbers, and mean nuclear to cell area ratio of in vitro root meristem cells were slightly higher compared to in vivo values. However, in vitro plants produced lower mean cell areas but higher nuclear areas when compared to in vivo plants. Thus, no occurrence of somaclonal variation was detected, and this was supported by morphological features of the in vitro plants. PMID:22593677

A prospective, observational study comparing the PK/PD relationships of generic Meropenem (Mercide®) to the innovator brand in critically ill patients

PubMed Central

Mer, Mervyn; Snyman, Jacques Rene; van Rensburg, Constance Elizabeth Jansen; van Tonder, Jacob John; Laurens, Ilze

2016-01-01

Introduction Clinicians’ skepticism, fueled by evidence of inferiority of some multisource generic antimicrobial products, results in the underutilization of more cost-effective generics, especially in critically ill patients. The aim of this observational study was to demonstrate equivalence between the generic or comparator brand of meropenem (Mercide®) and the leading innovator brand (Meronem®) by means of an ex vivo technique whereby antimicrobial activity is used to estimate plasma concentration of the active moiety. Methods Patients from different high care and intensive care units were recruited for observation when prescribed either of the meropenem brands under investigation. Blood samples were collected over 6 hours after a 30 minute infusion of the different brands. Meropenem concentration curves were established against United States Pharmacopeia standard meropenem (Sigma-Aldrich) by using standard laboratory techniques for culture of Klebsiella pneumoniae. Patients’ plasma samples were tested ex vivo, using a disc diffusion assay, to confirm antimicrobial activity and estimate plasma concentrations of the two brands. Results Both brands of meropenem demonstrated similar curves in donor plasma when concentrations in vials were confirmed. Patient-specific serum concentrations were determined from zones of inhibition against a standard laboratory Klebsiella strain ex vivo, confirming at least similar in vivo concentrations as the concentration curves (90% confidence interval) overlapped; however, the upper limit of the area under the curve for the ratio comparator/innovator exceeded the 1.25-point estimate, i.e., 4% higher for comparator meropenem. Conclusion This observational, in-practice study demonstrates similar ex vivo activity and in vivo plasma concentration time curves for the products under observation. Assay sensitivity is also confirmed. Current registration status of generic small molecules is in place. The products are therefore clinically interchangeable based on registration status as well as bioassay results, demonstrating sufficient overlap for clinical comfort. The slightly higher observed comparator meropenem concentration (4%) is still clinically acceptable due to the large therapeutic index and should ally fears of inferiority. PMID:27895516

Multiscale multimodal fusion of histological and MRI volumes for characterization of lung inflammation

NASA Astrophysics Data System (ADS)

Rusu, Mirabela; Wang, Haibo; Golden, Thea; Gow, Andrew; Madabhushi, Anant

2013-03-01

Mouse lung models facilitate the investigation of conditions such as chronic inflammation which are associated with common lung diseases. The multi-scale manifestation of lung inflammation prompted us to use multi-scale imaging - both in vivo, ex vivo MRI along with ex vivo histology, for its study in a new quantitative way. Some imaging modalities, such as MRI, are non-invasive and capture macroscopic features of the pathology, while others, e.g. ex vivo histology, depict detailed structures. Registering such multi-modal data to the same spatial coordinates will allow the construction of a comprehensive 3D model to enable the multi-scale study of diseases. Moreover, it may facilitate the identification and definition of quantitative of in vivo imaging signatures for diseases and pathologic processes. We introduce a quantitative, image analytic framework to integrate in vivo MR images of the entire mouse with ex vivo histology of the lung alone, using lung ex vivo MRI as conduit to facilitate their co-registration. In our framework, we first align the MR images by registering the in vivo and ex vivo MRI of the lung using an interactive rigid registration approach. Then we reconstruct the 3D volume of the ex vivo histological specimen by efficient group wise registration of the 2D slices. The resulting 3D histologic volume is subsequently registered to the MRI volumes by interactive rigid registration, directly to the ex vivo MRI, and implicitly to in vivo MRI. Qualitative evaluation of the registration framework was performed by comparing airway tree structures in ex vivo MRI and ex vivo histology where airways are visible and may be annotated. We present a use case for evaluation of our co-registration framework in the context of studying chronic inammation in a diseased mouse.

Oral cancer radiotherapy affects enamel microhardness and associated indentation pattern morphology

PubMed Central

Seyedmahmoud, R.; Thiagarajan, G.; Gorski, J. P.; Reed Edwards, R.; McGuire, J. D.

2017-01-01

Objectives The aim of this study is to determine the effects of in vitro and in vivo high-dose radiotherapy on microhardness and associated indentation pattern morphology of enamel. Materials and methods The inner, middle, and outer microhardness of enamel was evaluated using three experimental groups: control (non-radiated); in vitro irradiated; in vivo irradiated. In vitro specimens were exposed to simulated radiotherapy, and in vivo specimens were extracted teeth from oral cancer patients previously treated with radiotherapy. Indentations were measured via SEM images to calculate microhardness values and to assess the mechanomorphological properties of enamel before and after radiotherapy. Results Middle and outer regions of enamel demonstrated a significant decrease in microhardness after in vitro and in vivo irradiation compared to the control group (p < 0.05). Two indentation patterns were observed: pattern A—presence of microcracks around indent periphery, which represents local dissipation of deformation energy; pattern B—clean, sharp indents. The percentage of clean microindentation patterns, compared to controls, was significantly higher following in vitro and in vivo irradiation in all enamel regions. The highest percentage of clean microindentations (65%) was observed in the in vivo irradiated group in the inner region of enamel near the dentin-enamel junction. Conclusions For the first time, this study shows that in vitro and in vivo irradiation alters enamel microhardness. Likewise, the indentation pattern differences suggest that enamel may become more brittle following in vitro and in vivo irradiation. Clinical relevance The mechanomorphological property changes of enamel following radiation may be a contributory component of pathologic enamel delamination following oral cancer radiotherapy. PMID:29151196

Determination of uncertainties associated to the in vivo measurement of iodine-131 in the thyroid.

PubMed

Dantas, B M; Lima, F F; Dantas, A L; Lucena, E A; Gontijo, R M G; Carvalho, C B; Hazin, C

2016-07-01

Intakes of radionuclides can be estimated through in vivo measurements, and the uncertainties associated to the measured activities should be clearly stated in monitoring program reports. This study aims to evaluate the uncertainties of in vivo monitoring of iodine 131 in the thyroid. The reference values for high-energy photons are based on the IDEAS Guide. Measurements were performed at the In Vivo Monitoring Laboratory of the Institute of Radiation Protection and Dosimetry (IRD) and at the Internal Dosimetry Laboratory of the Regional Center of Nuclear Sciences (CRCN-NE). In both institutions, the experiment was performed using a NaI(Tl) 3''3″ scintillation detector and a neck-thyroid phantom. Scattering factors were calculated and compared in different counting geometries. The results show that the technique produces reproducibility equivalent to the values suggested in the IDEAS Guide and measurement uncertainties is comparable to international quality standards for this type of in vivo monitoring. Copyright © 2016 Elsevier Ltd. All rights reserved.

Lyophilized insulin nanoparticles prepared from quaternized N-aryl derivatives of chitosan as a new strategy for oral delivery of insulin: in vitro, ex vivo and in vivo characterizations.

PubMed

Mahjub, Reza; Radmehr, Moojan; Dorkoosh, Farid Abedin; Ostad, Seyed Naser; Rafiee-Tehrani, Morteza

2014-12-01

The purpose of this research was the development, in vitro, ex vivo and in vivo characterization of lyophilized insulin nanoparticles prepared from quaternized N-aryl derivatives of chitosan. Insulin nanoparticles were prepared from methylated N-(4-N,N-dimethylaminobenzyl), methylated N-(4 pyridinyl) and methylated N-(benzyl). Insulin nanoparticles containing non-modified chitosan and also trimethyl chiotsan (TMC) were also prepared as control. The effects of the freeze-drying process on physico-chemical properties of nanoparticles were investigated. The release of insulin from the nanoparticles was studied in vitro. The mechanism of the release of insulin from different types of nanoparticles was determined using curve fitting. The secondary structure of the insulin released from the nanoparticles was analyzed using circular dichroism and the cell cytotoxicity of nanoparticles on a Caco-2 cell line was determined. Ex vivo studies were performed on excised rat jejunum using Frantz diffusion cells. In vivo studies were performed on diabetic male Wistar rats and blood glucose level and insulin serum concentration were determined. Optimized nanoparticles with proper physico-chemical properties were obtained. The lyophilization process was found to cause a decrease in zeta potential and an increase in PdI as well as and a decrease in entrapment efficiency (EE%) and loading efficiency (LE%) but conservation in size of nanoparticles. Atomic force microscopy (AFM) images showed non-aggregated, stable and spherical to sub-spherical nanoparticles. The in vitro release study revealed higher release rates for lyophilized compared to non-lyophilized nanoparticles. Cytotoxicity studies on Caco-2 cells revealed no significant cytotoxicity for prepared nanoparticles after 3-h post-incubation but did show the concentration-dependent cytotoxicity after 24 h. The percentage of cumulative insulin determined from ex vivo studies was significantly higher in nanoparticles prepared from quaternized aromatic derivatives of chitosan. In vivo data showed significantly higher insulin intestinal absorption in nanoparticles prepared from methylated N-(4-N, N-dimethylaminobenzyl) chitosan nanoparticles compared to trimethyl chitosan. These data obtained demonstrated that as the result of optimized physico-chemical properties, drug release rate, cytotoxicity profile, ex vivo permeation enhancement and increased in vivo absorption, nanoparticles prepared from N-aryl derivatives of chitosan can be considered as valuable method for the oral delivery of insulin.

Pharmacological evaluation of mangiferin herbosomes for antioxidant and hepatoprotection potential against ethanol induced hepatic damage.

PubMed

Jain, Pushpendra Kumar; Kharya, Murlidhar; Gajbhiye, Asmita

2013-11-01

Fatty liver is the first stage of alcoholic damage which is reversible with abstinence from alcohol. Mangiferin (MF) showed potent scavenging activity on diphenyl-1-picrylhydrazyl radicals which stimulate liver regeneration in various liver injuries. Although, MF shows hepatoprotection against various liver disorders but due to rapid clearance and limited solubility in lipoid environment, there is problem of its poor absorption from intestine hence poor bioavailability. Owing to which there is a need to develop MF herbosomes to resolve the problem of poor bioavailability to enhance the therapeutic potential. Successfully prepared MF herbosomes through complexation with phospholipids were characterized by physicochemical, chromatography, spectroscopy (differential scanning calorimetry (DSC), infrared (IR), and nuclear magnetic resonance (NMR)), ex vivo absorption using everted small intestine sac technique and in vivo studies using ethanol inducing hepatotoxicity in albino rats and comparing the results against plain MF. Ex vivo study showed significant increased absorption of MF from prepared MF herbosomes as compared to plain MF. The hepatoprotective potential of MF herbosomes evaluated by in vivo study revealed significantly decreased levels of serum glutamate oxaloacetate transminase (SGOT), serum glutamate pyruvate transminase (SGPT), total bilirubin, and alkaline phosphatase (ALP) in MF herbosomes as compared to plain MF. MF herbosomes also showed significantly decreased level of malonyl dehydrogenase along with increased levels of reduced glutathione, superoxide dismutase (SOD) and catalase as compared to plain MF which was also comparable to the standard drug, silymarin (SL). The above mentioned results showed that hepatoprotective and antioxidant potency of MF enhanced due to the preparation of its herbosomes.

A level A in vitro/in vivo correlation in fasted and fed states using different methods: applied to solid immediate release oral dosage form.

PubMed

Souliman, Sabah; Blanquet, Stéphanie; Beyssac, Eric; Cardot, Jean-Michel

2006-01-01

The first purpose of this study was to simulate the impact of food intake on drug release and absorption in vivo using a novel in vitro system which mimics the gastro-intestinal (GI) tract in man. The drug studied was acetaminophen in the form of immediate release (IR) tablets. The second purpose was to establish a level A in vitro/in vivo correlation that could predict the bioavailability of a drug instead of using difficult, time-consuming and expensive in vivo bioequivalence studies. The artificial digestive system was used to estimate the availability of acetaminophen IR tablets for absorption in fasted and fed states. The same study was performed in vivo under similar conditions. A comparison study was carried out between the classical and the novel methods to estimate the efficacy of the new in vitro system to simulate the influence of food on drug release and absorption in vivo. A level A in vitro/in vivo correlation was established with a correlation coefficient of 0.9128 and 0.9984 in the fasted and fed states, respectively. Compared to USP II method, the novel in vitro model demonstrated a high level of efficacy in mimicking the behaviour of acetaminophen IR tablets in vivo in fasted and fed states.

In vitro-in vivo sequence studies as a method of selecting the most efficacious alcohol-based solution for hygienic hand disinfection.

PubMed

Herruzo, R; Vizcaino, M J; Herruzo, I

2010-05-01

The use of alcohol-based hand rubs serves to reduce hospital-acquired infections. Many products of this type are now on offer and it is essential to know how to rank their efficacy. A sequence of tests is proposed here to compare any given new alcohol-based solution against the reference solution (60% 2-isopropyl-alcohol) with 30 s of contact time: (i) in vitro (with pig skin as carrier) testing of >30 species of microorganism; (ii) in vitro assessment of residual efficacy (after 30 min of drying); (iii) in vivo study of transient microbiota (modification of the EN 1500 standard procedure) using four ATCC strains; (iv) in vivo study of resident hand microbiota. After performing the in vitro evaluation of seven alcohol-based hand rubs, the two most efficacious (chlorhexidine-quac-alcohol and mecetronium- alcohol) were chosen and studied, comparatively with the reference solution (60% isopropyl alcohol), in vitro (for chemical sustainability on the skin) and in vivo (against transient and resident microbiota). Chlorhexidine-quac-alcohol proved to be significantly superior to mecetronium-alcohol or the reference solution in all tests, except against resident microbiota for which the improvement was not statistically significant.

COMPARISON OF AN IN VIVO FISH VTG ASSAY WITH YES AND E-SCREEN

EPA Science Inventory

This study compares the efficacy of two in vitro, estrogen-sensitive bioassays to rank the "relative estrogenicity" of five natural, pharmaceutical and xenoestrogens with a newly developed in vivo bioassay. The E-SCREEN (MCF-7 tumor cells) and YES (Yeast Estrogen Screen) assays w...

Comparative In Vivo and Ex Vivo Toxicity Studies of Wildfire Particulate Matter

EPA Science Inventory

Inhalation of particulate matter (PM) generated from biomass burning is of concern particularly as the frequency and severity of wildfires have been increasing. Size-fractionated PM samples (ultrafine, <0.2 µm; fine, 0.2-2.5 µm; coarse, 2.5-10 µm) were colle...

In vitro and In vivo characterization of quercetin loaded multiphase hydrogel for wound healing application.

PubMed

Jangde, Rajendra; Srivastava, Shikha; Singh, Manju R; Singh, Deependra

2018-05-03

The present work aim to prepare and evaluate multiphase hydrogel system incorporated with quercetin loaded liposomes (QLH), for wound healing. The quercetin loaded liposomal hydrogel were prepared by taking 15% carbopol and varying gelatin ratio. The clear and transparent hydrogel was obtained by taking ratio of gelatin to carbapol (6/4) compared to other ratios. The best prepared hydrogel were characterized for surface morphology, water vapor transmission rate (WVTR), swelling ratio, hemocompatibility, stability, in-vitro release and in-vivo studies. The evaluated results of (QLH) for surface morphology, WVTR, swelling ratio, hemocompatibility and in-vitro release were found to be significant compared to other prepared formulations. Consequently, on basis of optimized hydrogel was selected to study wound healing activity in albino rats. The results demonstrated accelerated wound-healing with significant decrease in wound closure time compared to conventional dosage form. The results of in-vitro and in-vivo promises reliable mode of treatment for connective tissue disorder as wound healing. Copyright © 2018. Published by Elsevier B.V.

Comparison of Sequential Drug Release in Vitro and in Vivo

PubMed Central

Sundararaj, Sharath C.; Al-Sabbagh, Mohanad; Rabek, Cheryl L.; Dziubla, Thomas D.; Thomas, Mark V.; Puleo, David A.

2015-01-01

Development of drug delivery devices typically involves characterizing in vitro release performance with the inherent assumption that this will closely approximate in vivo performance. Yet, as delivery devices become more complex, for instance with a sequential drug release pattern, it is important to confirm that in vivo properties correlate with the expected “programming” achieved in vitro. In this work, a systematic comparison between in vitro and in vivo biomaterial erosion and sequential release was performed for a multilayered association polymer system comprising cellulose acetate phthalate and Pluronic F-127. After assessing the materials during incubation in phosphate-buffered saline, devices were implanted supracalvarially in rats. Devices with two different doses and with different erosion rates were harvested at increasing times post-implantation, and the in vivo thickness loss, mass loss, and the drug release profiles were compared with their in vitro counterparts. The sequential release of four different drugs observed in vitro was successfully translated to in vivo conditions. Results suggest, however, that the total erosion time of the devices was longer and release rates of the four drugs were different, with drugs initially released more quickly and then more slowly in vivo. Whereas many comparative studies of in vitro and in vivo drug release from biodegradable polymers involved a single drug, the present research demonstrated that sequential release of four drugs can be maintained following implantation. PMID:26111338

In vitro-in vivo correlation for nevirapine extended release tablets.

PubMed

Macha, Sreeraj; Yong, Chan-Loi; Darrington, Todd; Davis, Mark S; MacGregor, Thomas R; Castles, Mark; Krill, Steven L

2009-12-01

An in vitro-in vivo correlation (IVIVC) for four nevirapine extended release tablets with varying polymer contents was developed. The pharmacokinetics of extended release formulations were assessed in a parallel group study with healthy volunteers and compared with corresponding in vitro dissolution data obtained using a USP apparatus type 1. In vitro samples were analysed using HPLC with UV detection and in vivo samples were analysed using a HPLC-MS/MS assay; the IVIVC analyses comparing the two results were performed using WinNonlin. A Double Weibull model optimally fits the in vitro data. A unit impulse response (UIR) was assessed using the fastest ER formulation as a reference. The deconvolution of the in vivo concentration time data was performed using the UIR to estimate an in vivo drug release profile. A linear model with a time-scaling factor clarified the relationship between in vitro and in vivo data. The predictability of the final model was consistent based on internal validation. Average percent prediction errors for pharmacokinetic parameters were <10% and individual values for all formulations were <15%. Therefore, a Level A IVIVC was developed and validated for nevirapine extended release formulations providing robust predictions of in vivo profiles based on in vitro dissolution profiles. Copyright 2009 John Wiley & Sons, Ltd.

Experimental analysis of insertion torques and forces of threaded and press-fit acetabular cups by means of ex vivo and in vivo measurements.

PubMed

Vogel, Danny; Rathay, Andreas; Teufel, Stephanie; Ellenrieder, Martin; Zietz, Carmen; Sander, Manuela; Bader, Rainer

2017-01-01

In THA a sufficient primary implant stability is the precondition for successful secondary stability. Industrial foams of different densities have been used for primary stability investigations. The aim of this study was to analyse and compare the insertion behaviour of threaded and press-fit cups in vivo and ex vivo using bone substitutes with various densities. Two threaded (Bicon Plus®, Trident® TC) and one press-fit cup (Trident PSL®) were inserted by orthopaedic surgeons (S1, S2) into 10, 20 and 31 pcf blocks, using modified surgical instruments allowing measurements of the insertion forces and torques. Furthermore, the insertion behaviour of two cups were analysed intraoperatively. Torques for the threaded cups increased while bone substitute density increased. Maximum insertion torques were observed for S2 with 102 Nm for the Bicon Plus® in 20 pcf blocks and 77 Nm for the Trident® TC in 31 pcf blocks, which compares to the in vivo measurement (85 Nm). The average insertion forces for the press-fit cup varied from 5.2 to 6.8 kN (S1) and 7.2-11.5 kN (S2) ex vivo. Intraoperatively an average insertion force of 8.0 kN was determined. Implantation behaviour was influenced by acetabular cup design, bone substitute and experience of the surgeon. No specific density of bone substitute could be favoured for ex vivo investigations on the implantation behaviour of acetabular cups. The use synthetic bone blocks of high density (31 pcf) led to problems regarding cup orientation and seating. Therefore, bone substitutes used should be critically scrutinized in terms of the comparability to the in vivo situation.

DMS-MaPseq for genome-wide or targeted RNA structure probing in vivo.

PubMed

Zubradt, Meghan; Gupta, Paromita; Persad, Sitara; Lambowitz, Alan M; Weissman, Jonathan S; Rouskin, Silvi

2017-01-01

Coupling of structure-specific in vivo chemical modification to next-generation sequencing is transforming RNA secondary structure studies in living cells. The dominant strategy for detecting in vivo chemical modifications uses reverse transcriptase truncation products, which introduce biases and necessitate population-average assessments of RNA structure. Here we present dimethyl sulfate (DMS) mutational profiling with sequencing (DMS-MaPseq), which encodes DMS modifications as mismatches using a thermostable group II intron reverse transcriptase. DMS-MaPseq yields a high signal-to-noise ratio, can report multiple structural features per molecule, and allows both genome-wide studies and focused in vivo investigations of even low-abundance RNAs. We apply DMS-MaPseq for the first analysis of RNA structure within an animal tissue and to identify a functional structure involved in noncanonical translation initiation. Additionally, we use DMS-MaPseq to compare the in vivo structure of pre-mRNAs with their mature isoforms. These applications illustrate DMS-MaPseq's capacity to dramatically expand in vivo analysis of RNA structure.

Formulation and Optimization of Candesartan Cilexetil Nano Lipid Carrier: In Vitro and In Vivo Evaluation.

PubMed

Paudel, Anjan; Ameeduzzafar; Imam, Syed Sarim; Fazil, Mohd; Khan, Shahroz; Hafeez, Abdul; Ahmad, Farhan Jalees; Ali, Asgar

2017-01-01

The objective of this study was to formulate and optimize Candesartan Cilexetil (CC) loaded nanostructured lipid carriers (NLCs) for enhanced oral bioavailability. Glycerol monostearate (GMS), Oleic acid, Tween 80 and Span 40 were selected as a solid lipid, liquid lipid, surfactant and co- surfactant, respectively. The CC-NLCs were prepared by hot emulsion probe sonication technique and optimized using experimental design approach. The formulated CC-NLCs were evaluated for various physicochemical parameters and further optimized formulation (CC-NLC-Opt) was assessed for in vivo pharmacokinetic and pharmacodynamic activity. The optimized formulation (CC-NLC-Opt) showed particle size (183.5±5.89nm), PDI (0.228±0.13), zeta potential (-28.2±0.99mV), and entrapment efficiency (88.9±3.69%). The comparative in vitro release study revealed that CC-NLC-Opt showed significantly better (p<0.05) release and enhanced permeation as compared to CC-suspension. The in vivo pharmacokinetic study gave many folds increase in oral bioavailability than CC suspension, which was further confirmed by antihypertensive activity in a murine model. Thus, the results of ex vivo permeation, pharmacokinetic study and pharmacodynamics study suggest the potential of CC-NLCs for improved oral delivery. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Continuous monitoring of haemoglobin concentration after in-vivo adjustment in patients undergoing surgery with blood loss.

PubMed

Frasca, D; Mounios, H; Giraud, B; Boisson, M; Debaene, B; Mimoz, O

2015-07-01

Non-invasive monitoring of haemoglobin concentration provides real-time measurement of haemoglobin concentration (SpHb) using multi-wavelength pulse co-oximetry. We hypothesised that in-vivo adjustment using the mean of three haemoglobinometer (HemoCue®) measurements from an arterial blood sample at the first SpHb measurement (HCueART) would increase the accuracy of the monitor. The study included 41 adults for a total of 173 measurements of haemoglobin concentration. In-vivo adjusted SpHb was automatically calculated by the following formula: in-vivo adjusted SpHb = unadjusted SpHb - (SpHb - HCueART). The accuracy of in-vivo adjusted SpHb was compared with SpHb retrospectively adjusted using the same formula, except for haemoglobin level which was assessed at the central laboratory and then compared with all other available invasive methods of haemoglobin measurement (co-oximetry, HbSAT; arterial HemoCue, HCueART; capillary HemoCue, HCueCAP). Compared with laboratory measurement of haemoglobin concentration, bias (precision) for unadjusted SpHb, in-vivo adjusted SpHb, retrospectively adjusted SpHb, HbSAT, HCueART and HCueCAP were -0.4 (1.4), -0.3 (1.1), -0.3 (1.1), -0.6 (0.7), 0.0 (0.4) and -0.5 (1.2) g.dl(-1) , respectively. In-vivo adjustment of SpHb values using the mean of three arterial HemoCue measurements improved the accuracy of the device similar to those observed after a retrospective adjustment using central laboratory haemoglobin level. © 2015 The Association of Anaesthetists of Great Britain and Ireland.

Evaluation of Ocular Irritation and Bioavailability of Voriconazole Loaded Microemulsion.

PubMed

Kumar, Rakesh; Sinha, Vivek Ranjan

2017-01-01

Voriconazole (VCZ), a second-generation antifungal with excellent attributes like, broad-spectrum activity, targeted delivery, and tolerability. VCZ loaded microemulsion could be an effective strategy for efficient ocular delivery of the drug. To perform corneal irritation studies and in vivo delivery of VCZ microemulsion to establish its potential as an efficient ocular delivery system. Ocular irritancy was performed by HETCAM (Hen's Egg Test Chorio Allantoic Membrane) assay, corneal histopathology and Draize test. Ex vivo and in vivo studies were performed to determine permeation efficiency of VCZ microemulsion. The irritation studies suggested the non-irritant nature of the microemulsion. The ex vivo studies performed on excised cornea displayed significant enhancement in drug permeation/penetration from microemulsion in contrast to the drug suspension. Further, the in vivo study confirmed the higher availability of VCZ (from microemulsion) in aqueous humor with minimal nasolacrimal drainage (lower plasma drug content) when compared with the drug suspension. The non-irritant nature and high corneal permeation of VCZ encourages the role of microemulsion as a potential ocular delivery system. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Inclusion of Regional Poroelastic Material Properties Better Predicts Biomechanical Behavior of Lumbar Discs Subjected to Dynamic Loading

PubMed Central

Williams, Jamie R.; Natarajan, Raghu N.; Andersson, Gunnar B.J.

2009-01-01

Understanding the relationship between repetitive lifting and the breakdown of disc tissue over several years of exposure is difficult to study in vivo and in vitro. The aim of this investigation was to develop a three-dimensional poroelastic finite element model of a lumbar motion segment that reflects the biological properties and behaviors of in vivo disc tissues including swelling pressure due to the proteoglycans and strain dependent permeability and porosity. It was hypothesized that when modeling the annulus, prescribing tissue specific material properties will not be adequate for studying the in vivo loading and unloading behavior of the disc. Rather, regional variations of these properties, which are known to exist within the annulus, must also be included. Finite element predictions were compared to in vivo measurements published by Tyrrell et al., (Tyrrell et al., 1985) of percent change in total stature for two loading protocols, short-term creep loading and standing recovery and short-term cyclic loading with standing recovery. The model in which the regional variations of material properties in the annulus had been included provided an overall better prediction of the in vivo behavior as compared to the model in which the annulus properties were assumed to be homogenous. This model will now be used to study the relationship between repetitive lifting and disc degeneration. PMID:17156786

Evaluating bioequivalence of meloxicam tablets: is in-vitro dissolution test overdiscriminating?

PubMed

Jin, Chan; Zhao, Chenyao; Shen, Dachao; Dong, Wenxiang; Liu, Hongzhuo; He, Zhonggui

2018-02-01

The aim of the study was to assess the impact of the differences in dissolution profiles of meloxicam tablets on the in-vivo bioavailability parameters after oral administration. Compare in-vitro dissolution testing in the recommended media to evaluate in-vivo bioequivalence outcomes for the Biopharmaceutics Classification System Class II weak acidic drugs. Nine Beagle dogs received a single oral administration of each formulation (7.5 mg) in a three-way crossover design. The dissolution of meloxicam from both test products showed marked differences with that from the reference tablet in pH 1.0, 4.5 and 6.8 media at 50 or 75 rpm. Both formulations exhibiting slow or fast dissolution were then compared with the reference product for in-vivo bioequivalence study. Both products were bioequivalent with the reference tablet in either extent or rate of oral absorption. It indicated that the dissolution profiles which discriminated between the formulations in vitro did not accurately predict the in-vivo bioequivalence outcomes. Comparative dissolution profiles using similarity factor (f 2 ) in the recommended media should be relaxed to fulfil the requirements for the development, scale-up and postapproval changes to immediate release oral solid dosage forms of meloxicam. © 2017 Royal Pharmaceutical Society.

Comparative Psychotherapy: Rational-Emotive Therapy Versus Systematic Desensitization in the Treatment of Stuttering

ERIC Educational Resources Information Center

Moleski, Richard; Tosi, Donald J.

1976-01-01

The present study examined the efficacy of rational-emotive psychotherapy and systematic desensitization in the treatment of stuttering. Both therapies, making extensive use of in vivo behavioral assignments, were examined under the presence and absence of in vivo tasks. Results show that rational-emotive therapy was more effective in reducing…

Comparative lung toxicity of engineered nanomaterials (ENM) utilizing in vitro, ex vivo and in vivo approaches

EPA Science Inventory

Background: Although engineered nanomaterials (ENM) are currently regulated either in the context of a new chemical, or as a new use of an existing chemical, hazard assessment is still to a large extent reliant on information from historical toxicity studies of the parent compoun...

Can we use an ex vivo continuous hemofiltration model to describe the adsorption and elimination of meropenem and piperacillin?

PubMed

Jamal, Janattul-Ain; Udy, Andrew A; Wallis, Steven C; Ranganathan, Dwarakanathan; McWhinney, Brett C; Ungerer, Jacobus P J; Lipman, Jeffrey; Roberts, Jason A

2015-08-01

To determine the adsorption and elimination characteristics of meropenem and piperacillin during simulated continuous renal replacement therapy (CRRT), and to compare the observed data from this ex vivo study with previous data from clinical studies. This was an experimental study utilizing a modified CRRT circuit and polysulfone membrane (1.2 m2), circulated with a blood-crystalloid mixture. Adsorption onto the CRRT circuit was tested over a 4-h period, and clearance was assessed separately using variable continuous hemofiltration settings. A rapid 9% reduction in circulating meropenem and piperacillin concentrations was observed at approximately 0.5 and 1.0 h for each antibiotic, respectively. The post-dilution setting was associated with a significantly higher sieving coefficient (Sc) and filter clearance (CLfilter) (mean ± SD) (Sc 1.14 ± 0.10 versus 1.06 ± 0.04; CLfilter 19.05 ± 1.63 versus 17.59 ± 0.62 ml/min, P values < 0.05) for meropenem. No significant differences were observed for piperacillin pharmacokinetics. Clinically comparable Sc data were observed between data obtained from the ex vivo study and data from previous clinical studies, for both antibiotics. Meropenem and piperacillin appear to be rapidly adsorbed into the CRRT circuit, and the delivery site of fluid replacement significantly influences meropenem pharmacokinetics. However, these findings are likely to be clinically insignificant and not affect dosing requirements. This ex vivo method could be a surrogate for future clinical pharmacokinetic studies of CRRT. Further research is required to explore the applicability of the ex vivo method to further characterize antibiotic pharmacokinetics during CRRT.

Comparative analysis of cell killing and autosomal mutation in mouse kidney epithelium exposed to 1 GeV protons in vitro or in vivo.

PubMed

Kronenberg, Amy; Gauny, Stacey; Kwoh, Ely; Grossi, Gianfranco; Dan, Cristian; Grygoryev, Dmytro; Lasarev, Michael; Turker, Mitchell S

2013-05-01

Human exposure to high-energy protons occurs in space flight scenarios or, where necessary, during radiotherapy for cancer or benign conditions. However, few studies have assessed the mutagenic effectiveness of high-energy protons, which may contribute to cancer risk. Mutations cause cancer and most cancer-associated mutations occur at autosomal loci. This study addresses the cytotoxic and mutagenic effects of 1 GeV protons in mouse kidney epithelium. Mutant fractions were measured for an endogenous autosomal locus (Aprt) that detects all types of mutagenic events. Results for kidneys irradiated in vivo are compared with the results for kidney cells from the same strain exposed in vitro. The results demonstrate dose-dependent cell killing in vitro and for cells explanted 3-4 months postirradiation in vivo. Incubation in vivo for longer periods (8-9 months) further attenuates proton-induced cell killing. Protons are mutagenic to cells in vitro and for in vivo irradiated kidneys. The dose-response for Aprt mutation is curvilinear after in vitro or in vivo exposure, bending upward at the higher doses. While the absolute mutant fractions are higher in vivo, the fold-increase over background is similar for both in vitro and in situ exposures. Results are also presented for a limited study on the effect of dose fractionation on the induction of Aprt mutations in kidney epithelial cells. Dose-fractionation reduces the fraction of proton-induced Aprt mutants in vitro and in vivo and also results in less cell killing. Taken together, the mutation burden in the epithelium is slightly reduced by dose-fractionation. Autosomal mutations accumulated during clinical exposure to high-energy protons may contribute to the risk of treatment-associated neoplasms, thereby highlighting the need for rigorous treatment planning to reduce the dose to normal tissues. For low dose exposures that occur during most space flight scenarios, the mutagenic effects of protons appear to be modest.

In vivo characterization of hair and skin derived carbon quantum dots with high quantum yield as long-term bioprobes in zebrafish

PubMed Central

Zhang, Jing-Hui; Niu, Aping; Li, Jing; Fu, Jian-Wei; Xu, Qun; Pei, De-Sheng

2016-01-01

Carbon quantum dots (CDs) were widely investigated because of their tunable fluorescence properties and low toxicity. However, so far there have been no reports on in vivo functional studies of hair and skin derived CDs. Here, hair derived CDs (HCDs) and skin derived CDs (SCDs) were produced by using human hair and pig skin as precursors. The quantum yields (QYs) of HCDs and SCDs were quite high, compared to citric acid derived CDs (CCDs). HCDs and SCDs possess optimal photostability, hypotoxicity and biocompatibility in zebrafish, indicating that HCDs and SCDs possess the capacity of being used as fluorescence probes for in vivo biological imaging. The long-time observation for fluorescence alternation of CDs in zebrafish and the quenching assay of CDs by ATP, NADH and Fe3+ ions demonstrated that the decaying process of CDs in vivo might be induced by the synergistic effect of the metabolism process. All results indicated that large batches and high QYs of CDs can be acquired by employing natural and nontoxic hair and skin as precursors. To our knowledge, this is the first time to report SCDs, in vivo comparative studies of HCDs, SCDs and CCDs as bioprobes, and explore their mechanism of photostability in zebrafish. PMID:27886267

In vivo characterization of hair and skin derived carbon quantum dots with high quantum yield as long-term bioprobes in zebrafish.

PubMed

Zhang, Jing-Hui; Niu, Aping; Li, Jing; Fu, Jian-Wei; Xu, Qun; Pei, De-Sheng

2016-11-25

Carbon quantum dots (CDs) were widely investigated because of their tunable fluorescence properties and low toxicity. However, so far there have been no reports on in vivo functional studies of hair and skin derived CDs. Here, hair derived CDs (HCDs) and skin derived CDs (SCDs) were produced by using human hair and pig skin as precursors. The quantum yields (QYs) of HCDs and SCDs were quite high, compared to citric acid derived CDs (CCDs). HCDs and SCDs possess optimal photostability, hypotoxicity and biocompatibility in zebrafish, indicating that HCDs and SCDs possess the capacity of being used as fluorescence probes for in vivo biological imaging. The long-time observation for fluorescence alternation of CDs in zebrafish and the quenching assay of CDs by ATP, NADH and Fe 3+ ions demonstrated that the decaying process of CDs in vivo might be induced by the synergistic effect of the metabolism process. All results indicated that large batches and high QYs of CDs can be acquired by employing natural and nontoxic hair and skin as precursors. To our knowledge, this is the first time to report SCDs, in vivo comparative studies of HCDs, SCDs and CCDs as bioprobes, and explore their mechanism of photostability in zebrafish.

In vivo characterization of hair and skin derived carbon quantum dots with high quantum yield as long-term bioprobes in zebrafish

NASA Astrophysics Data System (ADS)

Zhang, Jing-Hui; Niu, Aping; Li, Jing; Fu, Jian-Wei; Xu, Qun; Pei, De-Sheng

2016-11-01

Carbon quantum dots (CDs) were widely investigated because of their tunable fluorescence properties and low toxicity. However, so far there have been no reports on in vivo functional studies of hair and skin derived CDs. Here, hair derived CDs (HCDs) and skin derived CDs (SCDs) were produced by using human hair and pig skin as precursors. The quantum yields (QYs) of HCDs and SCDs were quite high, compared to citric acid derived CDs (CCDs). HCDs and SCDs possess optimal photostability, hypotoxicity and biocompatibility in zebrafish, indicating that HCDs and SCDs possess the capacity of being used as fluorescence probes for in vivo biological imaging. The long-time observation for fluorescence alternation of CDs in zebrafish and the quenching assay of CDs by ATP, NADH and Fe3+ ions demonstrated that the decaying process of CDs in vivo might be induced by the synergistic effect of the metabolism process. All results indicated that large batches and high QYs of CDs can be acquired by employing natural and nontoxic hair and skin as precursors. To our knowledge, this is the first time to report SCDs, in vivo comparative studies of HCDs, SCDs and CCDs as bioprobes, and explore their mechanism of photostability in zebrafish.

Strong Correlation of Genome-Wide Expression after Traumatic Brain Injury In Vitro and In Vivo Implicates a Role for SORLA

PubMed Central

Lamprecht, Michael R.; Elkin, Benjamin S.; Kesavabhotla, Kartik; Crary, John F.; Hammers, Jennifer L.; Huh, Jimmy W.; Raghupathi, Ramesh

2017-01-01

Abstract The utility of in vitro models of traumatic brain injury (TBI) depends on their ability to recapitulate the in vivo TBI cascade. In this study, we used a genome-wide approach to compare changes in gene expression at several time points post-injury in both an in vitro model and an in vivo model of TBI. We found a total of 2073 differentially expressed genes in our in vitro model and 877 differentially expressed genes in our in vivo model when compared to noninjured controls. We found a strong correlation in gene expression changes between the two models (r = 0.69), providing confidence that the in vitro model represented at least part of the in vivo injury cascade. From these data, we searched for genes with significant changes in expression over time (analysis of covariance) and identified sorting protein-related receptor with A-type repeats (SORLA). SORLA directs amyloid precursor protein to the recycling pathway by direct binding and away from amyloid-beta producing enzymes. Mutations of SORLA have been linked to Alzheimer's disease (AD). We confirmed downregulation of SORLA expression in organotypic hippocampal slice cultures by immunohistochemistry and Western blotting and present preliminary data from human tissue that is consistent with these experimental results. Together, these data suggest that the in vitro model of TBI used in this study strongly recapitulates the in vivo TBI pathobiology and is well suited for future mechanistic or therapeutic studies. The data also suggest the possible involvement of SORLA in the post-traumatic cascade linking TBI to AD. PMID:26919808

Comparative evaluation of the efficacy of a herbal mouthwash and chlorhexidine mouthwash on select periodontal pathogens: An in vitro and ex vivo study

PubMed Central

Pathan, Multazim Muradkhan; Bhat, Kishore Gajanan; Joshi, Vinayak Mahableshwar

2017-01-01

Background: Several herbal mouthwash and herbal extracts have been tested in vitro and in vivo in search of a suitable adjunct to mechanical therapy for long-term use. In this study, we aimed to look at the antimicrobial effect of the herbal mouthwash and chlorhexidine (CHX) mouthwash on select organisms in in vitro test and an ex vivo model. Materials and Methods: The antimicrobial effects were determined against standard strains of bacteria that are involved in different stages of periodontal diseases. The in vitro tests included determination of minimum inhibitory concentration (MIC) using broth dilution and agar diffusion. In the ex vivo part of the study supragingival dental plaque were obtained from 20 periodontally healthy adult volunteers. Descriptive analysis was done for the entire quantitative and qualitative variable recorded. Results: The MIC by broth dilution method found no statistically significant difference between the mouthwashes. The agar dilution method showed CHX was more effective as compared to the herbal mouthwash against standard strains of Streptococcus mutans, Streptococcus sanguinis, and Aggregatibacter actinomycetemcomitans. However, no difference was observed between the mouthwashes for Porphyromonas, Pseudomonas aeruginosa, and Fusobacterium nucleatum. The ex vivo results conclude that none of the selected mouthwashes were statistically significantly different from each other. Conclusion: In the present study, CHX showed higher levels of antimicrobial action than the herbal mouthwash against bacterial species. The results reinforce the earlier findings that the in vitro testing is sensitive to methods and due diligence is needed when extrapolating the data for further use. However, long-term use and in vivo effectiveness against the periopathogens need to be tested in well-planned clinical trials. PMID:29456300

In vivo optical coherence tomography imaging and histopathology of healed coronary plaques.

PubMed

Shimokado, Aiko; Matsuo, Yoshiki; Kubo, Takashi; Nishiguchi, Tsuyoshi; Taruya, Akira; Teraguchi, Ikuko; Shiono, Yasutsugu; Orii, Makoto; Tanimoto, Takashi; Yamano, Takashi; Ino, Yasushi; Hozumi, Takeshi; Tanaka, Atsushi; Muragaki, Yasuteru; Akasaka, Takashi

2018-05-21

The aim of this study was to assess agreement between optical coherence tomography (OCT) and histopathology for healed coronary plaques (HCPs) in human coronary arteries ex vivo, and to evaluate the prevalence and characteristics of HCPs in vivo. Ex vivo OCT images were co-registered with histopathology in 144 cross-sections with ≥50% stenosis. Of these, 30 randomly selected pairs were employed to define morphological features of OCT for HCPs (OCT-derived HCPs); the remaining 114 pairs were used to evaluate the accuracy of OCT in detecting histologically-defined HCPs. In a clinical study, 60 target lesions from 60 patients with stable ischemic heart disease were divided into 2 groups according to the presence or absence of OCT-derived HCPs. Plaque characteristics were compared between the two groups. In the autopsy study, an OCT-derived HCP was defined as a plaque with heterogeneous signal-rich layers of different optical signal density. The sensitivity, specificity, positive predictive value, and negative predictive value of OCT-derived HCP to detect histologically-defined HCPs were 81%, 98%, 93%, and 93%, respectively. In the clinical study, 46 (77%) had OCT-derived HCPs. Both microvessels and macrophages were more frequently identified in OCT-derived HCPs compared to their counterparts (43% vs. 0%; p<0.01, 70% vs. 21%; p<0.01, respectively). An ex vivo OCT image has a good agreement with histology for HCPs detection. HCPs were frequently identified by OCT in target lesions in stable ischemic heart disease patients. OCT may be a useful intracoronary imaging for HCPs detection in vivo. Copyright © 2018 Elsevier B.V. All rights reserved.

Super hydrophilic thin film nitinol demonstrates reduced platelet adhesion compared with commercially available endograft materials.

PubMed

Tulloch, Allan W; Chun, Youngjae; Levi, Daniel S; Mohanchandra, Kotekar P; Carman, Gregory P; Lawrence, Peter F; Rigberg, David A

2011-11-01

Thin film nitinol (TFN) is a novel material with which to cover stents for the treatment of a wide range of vascular disease processes. This study aimed to show that TFN, if treated to produce a super hydrophilic surface, significantly reduces platelet adhesion, potentially rendering covered stents more resistant to thrombosis compared to commercially available materials. TFN was fabricated using a sputter deposition process to produce a 5-μ thin film of uniform thickness. TFN then underwent a surface treatment process to create a super hydrophilic layer. Platelet adhesion studies compared surface treated TFN (S-TFN) to untreated TFN, polytetrafluoroethylene, Dacron, and bulk nitinol. In vivo swine studies examined the placement of an S-TFN covered stent in a 3.5 mm diameter external iliac artery. Angiography confirmed placement, and repeat angiography was performed at 2 wk followed by post mortem histopathology. S-TFN significantly reduced platelet adhesion without any evidence of aggregation compared with all materials studied (P < 0.05). Furthermore, in vivo swine studies demonstrated complete patency of the S-TFN covered stent at 2 wk. Post mortem histopathology showed rapid endothelialization of the S-TFN without excessive neointimal hyperplasia. These results demonstrate that S-TFN significantly reduces platelet adhesion and aggregation compared with commercially available endograft materials. Furthermore, the hydrophilic surface may confer thromboresistance in vivo, suggesting that S-TFN is a possible superior material for covering stents. Copyright © 2011 Elsevier Inc. All rights reserved.

In vitro and in vivo evaluation of sanguinarine liposomes prepared by a remote loading method with three different ammonium salts.

PubMed

Ke, X; Bei, J H; Zhang, Y; Li, J

2011-04-01

Sanguinarine liposomes were prepared by a remote loading method using three different ammonium salts. A series of studies, including in vitro release, in vitro and in vivo anti-tumor effects and pharmacokinetics in rats, were conducted. The three liposomes showed pH-sensitive release characteristics in vitro, but there were obvious variations in their release profiles. Among the three liposomes, the liposomes made using ammonium citrate and phosphate possessed better anti-tumor activity in vitro and in vivo, compared with the liposome using ammonium sulfate. Pharmacokinetics test results in rats indicated that sanguinarine liposomes have notably elevated AUC (P<0.05) and markedly lower CL (P<0.05) compared with the solution, but there were no obvious differences between the three liposomes. The present study may be useful for better understanding and better choice of a suitable ammonium salt for the remote loading method.

Complex-Difference Constrained Compressed Sensing Reconstruction for Accelerated PRF Thermometry with Application to MRI Induced RF Heating

PubMed Central

Cao, Zhipeng; Oh, Sukhoon; Otazo, Ricardo; Sica, Christopher T.; Griswold, Mark A.; Collins, Christopher M.

2014-01-01

Purpose Introduce a novel compressed sensing reconstruction method to accelerate proton resonance frequency (PRF) shift temperature imaging for MRI induced radiofrequency (RF) heating evaluation. Methods A compressed sensing approach that exploits sparsity of the complex difference between post-heating and baseline images is proposed to accelerate PRF temperature mapping. The method exploits the intra- and inter-image correlations to promote sparsity and remove shared aliasing artifacts. Validations were performed on simulations and retrospectively undersampled data acquired in ex-vivo and in-vivo studies by comparing performance with previously proposed techniques. Results The proposed complex difference constrained compressed sensing reconstruction method improved the reconstruction of smooth and local PRF temperature change images compared to various available reconstruction methods in a simulation study, a retrospective study with heating of a human forearm in vivo, and a retrospective study with heating of a sample of beef ex vivo . Conclusion Complex difference based compressed sensing with utilization of a fully-sampled baseline image improves the reconstruction accuracy for accelerated PRF thermometry. It can be used to improve the volumetric coverage and temporal resolution in evaluation of RF heating due to MRI, and may help facilitate and validate temperature-based methods for safety assurance. PMID:24753099

Efficacy of silver diamine fluoride as an antibacterial as well as antiplaque agent compared to fluoride varnish and acidulated phosphate fluoride gel: an in vivo study.

PubMed

Shah, Shalin; Bhaskar, Vijay; Venkataraghavan, Karthik; Choudhary, Prashant; Ganesh, M; Trivedi, Krishna

2013-01-01

Silver diamine fluoride (SDF) is already proven as an antibacterial agent in vitro. Present study was formulated to compare the efficacy of SDF as an antibacterial as well as antiplaque agent in vivo with fluoride varnish and acidulated phosphate fluoride (APF) gel. Total 123 children (male = 82, female = 41) were included in the study for a period of 18 months. Children were divided into three different groups-Group 1: SDF; Group 2: fluoride varnish; and Group 3: APF gel. All subjects were evaluated via plaque score at 6 th, 12 th, and 18 th months as well as Streptococcus mutans counts in saliva at 72 h, 6 th, 12 th, and 18 th months of follow-up. Significant reduction was found in plaque score as well as S. mutans counts irrespective of group division. On intergroup comparison, no statistically significant difference was found in plaque score, but significant reduction in S. mutans counts was found in Group 1 as compared with Groups 2 and 3, while no significant difference was found between Groups 2 and 3. In vivo application of SDF on enamel significantly decreases S. mutans counts as compared to fluoride varnish and APF gel.

Development of bupivacaine decorated reduced graphene oxide and its local anesthetic effect-In vivo study.

PubMed

Zhang, Zhi; Zhang, Xin; Li, Aixiang; Ma, Chuangen

2018-03-01

The present works aims to develop bupivacaine modified reduced graphene oxide (BPV/RGO), and comparative evaluation of their anesthetic effect with free bupivacaine (BPV). The prepared BPV/RGO was studied by using various spectroscopic and microscopic characterization studies. In vitro drug release from BPV/RGO was studied using HPLC analysis. The cytotoxicity of BPV/RGO was studied against fibroblast (3T3) cells. In vivo evaluation of anesthetic effects was performed on animal models. BPV/RGO showed a prolonged in vitro release and lower cytotoxicity when compared to free BPV. Also, BPV/RGO showed a significantly prolonged analgesic effect when compared to free BPV. Further, the prepared BPV/RGO drug delivery system demonstrated to function as gifted to overcome the drawbacks of free BPV and other available drug delivery systems by prolonging the anesthetic effect with poor cytotoxicity. Copyright © 2018. Published by Elsevier B.V.

Analysis of ToxCast data for food-relevant compounds by comparison with in vivo data using the RISK21 approach

EPA Science Inventory

The ToxCast program has generated a wealth of in vitro high throughput screening data, and best approaches for the interpretation and use of these data remain undetermined. We present case studies comparing the ToxCast and in vivo toxicity data for two food contact substances us...

Antioxidant Activity and Total Phenolic and Flavonoid Content of Various Solvent Extracts from In Vivo and In Vitro Grown Trifolium pratense L. (Red Clover)

PubMed Central

Mat Taha, Rosna; Banisalam, Behrooz

2015-01-01

In the present study the extracts of in vivo and in vitro grown plants as well as callus tissue of red clover were tested for their antioxidant activities, using different extraction solvent and different antioxidant assays. The total flavonoid and phenolic contents as well as extraction yield of the extracts were also investigated to determine their correlation with the antioxidant activity of the extracts. Among all the tested extracts the highest amounts of total phenolic and total flavonoids content were found in methanol extract of in vivo grown plants. The antioxidant activity of tested samples followed the order in vivo plant extract > callus extract > in vitro extract. The highest reducing power, 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging, and chelating power were found in methanol extracts of in vivo grown red clover, while the chloroform fraction of in vivo grown plants showed the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, superoxide anion radical scavenging and hydrogen peroxide scavenging compared to the other tested extracts. A significant correlation was found between the antioxidant activity of extracts and their total phenolic and total flavonoid content. According to the findings, the extract of in vitro culture of red clover especially the callus tissue possesses a comparable antioxidant activity to the in vivo cultured plants' extract. PMID:26064936

Cell-Based Meniscus Repair and Regeneration: At the Brink of Clinical Translation?

PubMed Central

Korpershoek, Jasmijn V.; de Windt, Tommy S.; Hagmeijer, Michella H.; Vonk, Lucienne A.; Saris, Daniel B. F.

2017-01-01

Background: Meniscus damage can be caused by trauma or degeneration and is therefore common among patients of all ages. Repair or regeneration of the menisci could be of great importance not only for pain relief or regaining function but also to prevent degenerative disease and osteoarthritis. Current treatment does not offer consistent long-term improvement. Although preclinical research focusing on augmentation of meniscal tear repair and regeneration after meniscectomy is encouraging, clinical translation remains difficult. Purpose: To systematically evaluate the literature on in vivo meniscus regeneration and explore the optimal cell sources and conditions for clinical translation. We aimed at thorough evaluation of current evidence as well as clarifying the challenges for future preclinical and clinical studies. Study Design: Systematic review. Methods: A search was conducted using the electronic databases of MEDLINE, Embase, and the Cochrane Collaboration. Search terms included meniscus, regeneration, and cell-based. Results: After screening 81 articles based on title and abstract, 51 articles on in vivo meniscus regeneration could be included; 2 additional articles were identified from the references. Repair and regeneration of the meniscus has been described by intra-articular injection of multipotent mesenchymal stromal (stem) cells from adipose tissue, bone marrow, synovium, or meniscus or the use of these cell types in combination with implantable or injectable scaffolds. The use of fibrochondrocytes, chondrocytes, and transfected myoblasts for meniscus repair and regeneration is limited to the combination with different scaffolds. The comparative in vitro and in vivo studies mentioned in this review indicate that the use of allogeneic cells is as successful as the use of autologous cells. In addition, the implantation or injection of cell-seeded scaffolds increased tissue regeneration and led to better structural organization compared with scaffold implantation or injection of a scaffold alone. None of the studies mentioned in this review compare the effectiveness of different (cell-seeded) scaffolds. Conclusion: There is heterogeneity in animal models, cell types, and scaffolds used, and limited comparative studies are available. The comparative in vivo research that is currently available is insufficient to draw strong conclusions as to which cell type is the most promising. However, there is a vast amount of in vivo research on the use of different types of multipotent mesenchymal stromal (stem) cells in different experimental settings, and good results are reported in terms of tissue formation. None of these studies compare the effectiveness of different cell-scaffold combinations, making it hard to conclude which scaffold has the greatest potential. PMID:28321424

Comparative lung toxicity of engineered nanomaterials utilizing in vitro, ex vivo and in vivo approaches.

PubMed

Kim, Yong Ho; Boykin, Elizabeth; Stevens, Tina; Lavrich, Katelyn; Gilmour, M Ian

2014-11-26

Although engineered nanomaterials (ENM) are currently regulated either in the context of a new chemical, or as a new use of an existing chemical, hazard assessment is still to a large extent reliant on information from historical toxicity studies of the parent compound, and may not take into account special properties related to the small size and high surface area of ENM. While it is important to properly screen and predict the potential toxicity of ENM, there is also concern that current toxicity tests will require even heavier use of experimental animals, and reliable alternatives should be developed and validated. Here we assessed the comparative respiratory toxicity of ENM in three different methods which employed in vivo, in vitro and ex vivo toxicity testing approaches. Toxicity of five ENM (SiO2 (10), CeO2 (23), CeO2 (88), TiO2 (10), and TiO2 (200); parentheses indicate average ENM diameter in nm) were tested in this study. CD-1 mice were exposed to the ENM by oropharyngeal aspiration at a dose of 100 μg. Mouse lung tissue slices and alveolar macrophages were also exposed to the ENM at concentrations of 22-132 and 3.1-100 μg/mL, respectively. Biomarkers of lung injury and inflammation were assessed at 4 and/or 24 hr post-exposure. Small-sized ENM (SiO2 (10), CeO2 (23), but not TiO2 (10)) significantly elicited pro-inflammatory responses in mice (in vivo), suggesting that the observed toxicity in the lungs was dependent on size and chemical composition. Similarly, SiO2 (10) and/or CeO2 (23) were also more toxic in the lung tissue slices (ex vivo) and alveolar macrophages (in vitro) compared to other ENM. A similar pattern of inflammatory response (e.g., interleukin-6) was observed in both ex vivo and in vitro when a dose metric based on cell surface area (μg/cm(2)), but not culture medium volume (μg/mL) was employed. Exposure to ENM induced acute lung inflammatory effects in a size- and chemical composition-dependent manner. The cell culture and lung slice techniques provided similar profiles of effect and help bridge the gap in our understanding of in vivo, ex vivo, and in vitro toxicity outcomes.

Comparison of surface modified zirconia implants with commercially available zirconium and titanium implants: a histological study in pigs.

PubMed

Gredes, Tomasz; Kubasiewicz-Ross, Pawel; Gedrange, Tomasz; Dominiak, Marzena; Kunert-Keil, Christiane

2014-08-01

New biomaterials and their various surface modifications should undergo in vitro and in vivo evaluation before clinical trials. The objective of our in vivo study was to evaluate the biocompatibility of newly created zirconium implant surfaces after implantation in the lower jaw of pigs and compare the osseointegration of these dental implants with commercially available zirconium and titanium implants. After a healing period of 12 weeks, a histological analysis of the soft and hard tissues and a histomorphometric analysis of the bone-implant contact (BIC) were performed. The implant surfaces showed an intimate connection to the adjacent bone for all tested implants. The 3 newly created zirconium implant surfaces achieved a BIC of 45% on average in comparison with a BIC of 56% from the reference zirconium implants and 35% from titanium implants. Furthermore, the new zirconium implants had a better attachment to gingival and bone tissues in the range of implant necks as compared with the reference implants. The results suggest that the new implants comparably osseointegrate within the healing period, and they have a good in vivo biocompatibility.

Measuring Regional Changes in Damaged Tendon

NASA Astrophysics Data System (ADS)

Frisch, Catherine Kayt Vincent

Mechanical properties of tendon predict tendon health and function, but measuring these properties in vivo is difficult. An ultrasound-based (US) analysis technique called acoustoelastography (AE) uses load-dependent changes in the reflected US signal to estimate tissue stiffness non-invasively. This thesis explores whether AE can provide information about stiffness alteration resulting from tendon tears both ex vivo and in vivo. An ex vivo ovine infraspinatus tendon model suggests that the relative load transmitted by the different tendon layers transmit different fractions of the load and that ultrasound echo intensity change during cyclic loading decreases, becoming less consistent once the tendon is torn. An in vivo human tibialis anterior tendon model using electrically stimulated twitch contractions investigated the feasibility of measuring the effect in vivo. Four of the five subjects showed the expected change and that the muscle contraction times calculated using the average grayscale echo intensity change compared favorably with the times calculated based on the force data. Finally an AE pilot study with patients who had rotator cuff tendon tears found that controlling the applied load and the US view of the system will be crucial to a successful in vivo study.

Comparative Plasma Exposure of Albendazole after Administration of Rapidly Disintegrating Tablets in Dogs

PubMed Central

Castro, Silvina G.; Dib, Alicia; Suarez, Gonzalo; Allemandi, Daniel; Lanusse, Carlos; Sanchez Bruni, Sergio; Palma, Santiago D.

2013-01-01

The main objectives of this study were (a) to evaluate the in vitro performance of the rapid disintegration tablets as a way to improve the solid dispersions and (b) to study the in vivo pharmacokinetics of the albendazole modified formulation in dogs. Rapid disintegration of tablets seems to be a key factor for efficiency of solid dispersions with regard to improvement of the albendazole bioavailability. The in vivo assays performed on dogs showed a marked increase in drug plasma exposure when albendazole was given in solid dispersions incorporated into rapid disintegration tablets compared with conventional solid dosage form. PMID:24063016

Development and in vitro-in vivo evaluation of a water-in-oil microemulsion formulation for the oral delivery of troxerutin.

PubMed

Xu, Man; Yu, Qing; Zhao, Qianru; Chen, Wei; Lin, Yuanjie; Jin, Yong

2016-01-01

The main objective of this study was to develop and evaluate a W/O microemulsion formulation of troxerutin to improve its oral bioavailability. The W/O microemulsion was optimized using a pseudo-ternary phase diagram and evaluated for physical properties. In vitro MDCK cell permeability studies were carried out to evaluate the permeability enhancement effect of microemulsion, and in vivo absorption of troxerutin microemulsion in the intestine was compared with that of solution after single-dose administration (56.7 mg/kg) in male Wistar rats. The optimal formulation consisted of lecithin, ethanol, isopropyl myristate and water (23.30/11.67/52.45/12.59 w/w) was physicochemical stable and the mean droplet size was about 50.20 nm. In vitro study, the troxerutin-loaded microemulsion showed higher intestinal membrane permeability across MDCK monolayer when compared with the control solution. The W/O microemulsion can significantly promote the intestinal absorption of troxerutin in rats in vivo, and the relative bioavailability of the microemulsion was about 205.55% compared to control solution. These results suggest that novel W/O microemulsion could be used as an effective formulation for improving the oral bioavailability of troxerutin.

Mechanical properties of porcine brain tissue in vivo and ex vivo estimated by MR elastography.

PubMed

Guertler, Charlotte A; Okamoto, Ruth J; Schmidt, John L; Badachhape, Andrew A; Johnson, Curtis L; Bayly, Philip V

2018-03-01

The mechanical properties of brain tissue in vivo determine the response of the brain to rapid skull acceleration. These properties are thus of great interest to the developers of mathematical models of traumatic brain injury (TBI) or neurosurgical simulations. Animal models provide valuable insight that can improve TBI modeling. In this study we compare estimates of mechanical properties of the Yucatan mini-pig brain in vivo and ex vivo using magnetic resonance elastography (MRE) at multiple frequencies. MRE allows estimations of properties in soft tissue, either in vivo or ex vivo, by imaging harmonic shear wave propagation. Most direct measurements of brain mechanical properties have been performed using samples of brain tissue ex vivo. It has been observed that direct estimates of brain mechanical properties depend on the frequency and amplitude of loading, as well as the time post-mortem and condition of the sample. Using MRE in the same animals at overlapping frequencies, we observe that porcine brain tissue in vivo appears stiffer than porcine brain tissue samples ex vivo at frequencies of 100 Hz and 125 Hz, but measurements show closer agreement at lower frequencies. Copyright © 2018 Elsevier Ltd. All rights reserved.

DMS-MaPseq for genome-wide or targeted RNA structure probing in vivo

PubMed Central

Zubradt, Meghan; Gupta, Paromita; Persad, Sitara; Lambowitz, Alan M.; Weissman, Jonathan S.; Rouskin, Silvi

2017-01-01

Coupling structure-specific in vivo chemical modification to next-generation sequencing is transforming RNA secondary structural studies in living cells. The dominant strategy for detecting in vivo chemical modifications uses reverse transcriptase truncation products, which introduces biases and necessitates population-average assessments of RNA structure. Here we present dimethyl sulfate mutational profiling with sequencing (DMS-MaPseq), which encodes DMS modifications as mismatches using a thermostable group II intron reverse transcriptase (TGIRT). DMS-MaPseq yields a high signal-to-noise ratio, can report multiple structural features per molecule, and allows both genome-wide studies and focused in vivo investigations of even low abundance RNAs. We apply DMS-MaPseq for the first analysis of RNA structure within an animal tissue and to identify a functional structure involved in non-canonical translation initiation. Additionally, we use DMS-MaPseq to compare the in vivo structure of pre-mRNAs to their mature isoforms. These applications illustrate DMS-MaPseq’s capacity to dramatically expand in vivo analysis of RNA structure. PMID:27819661

Coir fibre toxicity: in vivo and in vitro studies.

PubMed

Saxena, R P; Dogra, R K; Bhattacherjee, J W

1982-03-01

The biological activity of coir fibre, coir ash and their components were investigated in vitro by measuring the haemolytic activity and macrophage cytotoxicity. In vivo studies carried out by injecting guinea pigs intratracheally with coir fibres resulted in resolving granulomas. The observed haemolytic activity and macrophage cytotoxicity was more marked with coir ash compared with coir fibres. Chemical analysis of coir ash revealed the presence of toxic chemical constituents in appreciable amounts.

Ultrasound elastography as a tool for imaging guidance during prostatectomy: Initial experience

PubMed Central

Fleming, Ioana Nicolaescu; Kut, Carmen; Macura, Katarzyna J.; Su, Li-Ming; Rivaz, Hassan; Schneider, Caitlin; Hamper, Ulrike; Lotan, Tamara; Taylor, Russ; Hager, Gregory; Boctor, Emad

2012-01-01

Summary Background During laparoscopic or robotic assisted laparoscopic prostatectomy, the surgeon lacks tactile feedback which can help him tailor the size of the excision. Ultrasound elastography (USE) is an emerging imaging technology which maps the stiffness of tissue. In the paper we are evaluating USE as a palpation equivalent tool for intraoperative image guided robotic assisted laparoscopic prostatectomy. Material/Methods Two studies were performed: 1) A laparoscopic ultrasound probe was used in a comparative study of manual palpation versus USE in detecting tumor surrogates in synthetic and ex-vivo tissue phantoms; N=25 participants (students) were asked to provide the presence, size and depth of these simulated lesions, and 2) A standard ultrasound probe was used for the evaluation of USE on ex-vivo human prostate specimens (N=10 lesions in N=6 specimens) to differentiate hard versus soft lesions with pathology correlation. Results were validated by pathology findings, and also by in-vivo and ex-vivo MR imaging correlation. Results In the comparative study, USE displayed higher accuracy and specificity in tumor detection (sensitivity=84%, specificity=74%). Tumor diameters and depths were better estimated using USE versus with manual palpation. USE also proved consistent in identification of lesions in ex-vivo prostate specimens; hard and soft, malignant and benign, central and peripheral. Conclusions USE is a strong candidate for assisting surgeons by providing palpation equivalent evaluation of the tumor location, boundaries and extra-capsular extension. The results encourage us to pursue further testing in the robotic laparoscopic environment. PMID:23111738

A randomized comparison of laparoscopic, flexible endoscopic, and wired and wireless magnetic cameras on ex vivo and in vivo NOTES surgical performance.

PubMed

Chang, Victoria C; Tang, Shou-Jiang; Swain, C Paul; Bergs, Richard; Paramo, Juan; Hogg, Deborah C; Fernandez, Raul; Cadeddu, Jeffrey A; Scott, Daniel J

2013-08-01

The influence of endoscopic video camera (VC) image quality on surgical performance has not been studied. Flexible endoscopes are used as substitutes for laparoscopes in natural orifice translumenal endoscopic surgery (NOTES), but their optics are originally designed for intralumenal use. Manipulable wired or wireless independent VCs might offer advantages for NOTES but are still under development. To measure the optical characteristics of 4 VC systems and to compare their impact on the performance of surgical suturing tasks. VC systems included a laparoscope (Storz 10 mm), a flexible endoscope (Olympus GIF 160), and 2 prototype deployable cameras (magnetic anchoring and guidance system [MAGS] Camera and PillCam). In a randomized fashion, the 4 systems were evaluated regarding standardized optical characteristics and surgical manipulations of previously validated ex vivo (fundamentals of laparoscopic surgery model) and in vivo (live porcine Nissen model) tasks; objective metrics (time and errors/precision) and combined surgeon (n = 2) performance were recorded. Subtle differences were detected for color tests, and field of view was variable (65°-115°). Suitable resolution was detected up to 10 cm for the laparoscope and MAGS camera but only at closer distances for the endoscope and PillCam. Compared with the laparoscope, surgical suturing performances were modestly lower for the MAGS camera and significantly lower for the endoscope (ex vivo) and PillCam (ex vivo and in vivo). This study documented distinct differences in VC systems that may be used for NOTES in terms of both optical characteristics and surgical performance. Additional work is warranted to optimize cameras for NOTES. Deployable systems may be especially well suited for this purpose.

Imagery rescripting versus in vivo exposure in the treatment of snake fear.

PubMed

Hunt, Melissa; Fenton, Miriam

2007-12-01

This study compared imagery rescripting, in vivo exposure therapy and their combination in the treatment of snake fear. Imaginal ability was assessed pre-treatment, and was correlated with baseline avoidance. Snake fearful individuals were randomly assigned to cognitive therapy involving imagery rescripting, in vivo exposure, a combination of the two, or a relaxation control. All active treatment groups improved significantly more than the control group in both fearfulness and behavioral approach. There were no significant differences between the active treatment groups, although the combined treatment tended to be slightly more efficacious.

Mucoadhesive buccal patches based on interpolymer complexes of chitosan–pectin for delivery of carvedilol

PubMed Central

Kaur, Amanpreet; Kaur, Gurpreet

2011-01-01

The study was designed to develop bioadhesive patches of carvedilol hydrochloride using chitosan (CH) and pectin (PE) interpolymer complexes and to systematically evaluate their in vitro and in vivo performances. Mucoadhesive buccal patches of carvedilol were prepared using solvent casting method. The physicochemical interaction between CH and PE was investigated by FTIR and DSC studies. The patches were evaluated for their physical characteristics like mass variation, content uniformity, folding endurance, ex vivo mucoadhesion strength, ex vivo mucoadhesion time, surface pH, in vitro drug release, in situ release study, and in vivo bioavailability study. The swelling index of the patches was found to be proportional to the PE concentration. The surface pH of all the formulated bioadhesive patches was found to lie between 6.2 and 7.2. The optimized bioadhesive patch (C1, CH:PE 20:80) showed bioadhesive strength of 22.10 ± 0.20 g, in vitro release of 98.73% and ex vivo mucoadhesion time of 451 min with in a period of 8 h. The optimized patch demonstrated good in vitro and in vivo results. The buccal delivery of carvedilol in rabbits showed a significant improvement in bioavailability of carvedilol from patches when compared to oral route. PMID:23960773

Mucoadhesive buccal patches based on interpolymer complexes of chitosan-pectin for delivery of carvedilol.

PubMed

Kaur, Amanpreet; Kaur, Gurpreet

2012-01-01

The study was designed to develop bioadhesive patches of carvedilol hydrochloride using chitosan (CH) and pectin (PE) interpolymer complexes and to systematically evaluate their in vitro and in vivo performances. Mucoadhesive buccal patches of carvedilol were prepared using solvent casting method. The physicochemical interaction between CH and PE was investigated by FTIR and DSC studies. The patches were evaluated for their physical characteristics like mass variation, content uniformity, folding endurance, ex vivo mucoadhesion strength, ex vivo mucoadhesion time, surface pH, in vitro drug release, in situ release study, and in vivo bioavailability study. The swelling index of the patches was found to be proportional to the PE concentration. The surface pH of all the formulated bioadhesive patches was found to lie between 6.2 and 7.2. The optimized bioadhesive patch (C1, CH:PE 20:80) showed bioadhesive strength of 22.10 ± 0.20 g, in vitro release of 98.73% and ex vivo mucoadhesion time of 451 min with in a period of 8 h. The optimized patch demonstrated good in vitro and in vivo results. The buccal delivery of carvedilol in rabbits showed a significant improvement in bioavailability of carvedilol from patches when compared to oral route.

Histological Methods for ex vivo Axon Tracing: A Systematic Review

PubMed Central

Heilingoetter, Cassandra L.; Jensen, Matthew B.

2016-01-01

Objectives Axon tracers provide crucial insight into the development, connectivity, and function of neural pathways. A tracer can be characterized as a substance that allows for the visualization of a neuronal pathway. Axon tracers have previously been used exclusively with in vivo studies; however, newer methods of axon tracing can be applied to ex vivo studies. Ex vivo studies involve the examination of cells or tissues retrieved from an organism. These post mortem methods of axon tracing offer several advantages, such as reaching inaccessible tissues and avoiding survival surgeries. Methods In order to evaluate the quality of the ex vivo tracing methods, we performed a systematic review of various experimental and comparison studies to discern the optimal method of axon tracing. Results The most prominent methods for ex vivo tracing involve enzymatic techniques or various dyes. It appears that there are a variety of techniques and conditions that tend to give better fluorescent character, clarity, and distance traveled in the neuronal pathway. We found direct comparison studies that looked at variables such as the type of tracer, time required, effect of temperature, and presence of calcium, however, there are other variables that have not been compared directly. Discussion We conclude there are a variety of promising tracing methods available depending on the experimental goals of the researcher, however, more direct comparison studies are needed to affirm the optimal method. PMID:27098542

Histological methods for ex vivo axon tracing: A systematic review.

PubMed

Heilingoetter, Cassandra L; Jensen, Matthew B

2016-07-01

Axon tracers provide crucial insight into the development, connectivity, and function of neural pathways. A tracer can be characterized as a substance that allows for the visualization of a neuronal pathway. Axon tracers have previously been used exclusively with in vivo studies; however, newer methods of axon tracing can be applied to ex vivo studies. Ex vivo studies involve the examination of cells or tissues retrieved from an organism. These post mortem methods of axon tracing offer several advantages, such as reaching inaccessible tissues and avoiding survival surgeries. In order to evaluate the quality of the ex vivo tracing methods, we performed a systematic review of various experimental and comparison studies to discern the optimal method of axon tracing. The most prominent methods for ex vivo tracing involve enzymatic techniques or various dyes. It appears that there are a variety of techniques and conditions that tend to give better fluorescent character, clarity, and distance traveled in the neuronal pathway. We found direct comparison studies that looked at variables such as the type of tracer, time required, effect of temperature, and presence of calcium, however, there are other variables that have not been compared directly. We conclude there are a variety of promising tracing methods available depending on the experimental goals of the researcher, however, more direct comparison studies are needed to affirm the optimal method.

Live Birth from Slow-Frozen Rabbit Oocytes after In Vivo Fertilisation

PubMed Central

Jiménez-Trigos, Estrella; Vicente, José S.; Marco-Jiménez, Francisco

2013-01-01

In vivo fertilisation techniques such as intraoviductal oocyte transfer have been considered as alternatives to bypass the inadequacy of conventional in vitro fertilisation in rabbit. There is only one study in the literature, published in 1989, that reports live offspring from cryopreserved rabbit oocytes. The aim of the present study was to establish the in vivo fertilisation procedure to generate live offspring with frozen oocytes. First, the effect of two recipient models (i) ovariectomised or (ii) oviduct ligated immediately after transfer on the ability of fresh oocytes to fertilise were compared. Second, generation of live offspring from slow-frozen oocytes was carried out using the ligated oviduct recipient model. Throughout the experiment, recipients were artificially inseminated 9 hours prior to oocyte transfer. In the first experiment, two days after unilateral transfer of fresh oocytes, oviducts and uterine horns were flushed to assess embryo recovery rates. The embryo recovery rates were low compared to control in both ovariectomised and ligated oviduct groups. However, ligated oviduct recipient showed significantly (P<0.05) higher embryo recovery rates compared to ovariectomised and control-transferred. In the second experiment, using bilateral oviduct ligation model, all females that received slow-frozen oocytes became pregnant and delivered a total of 4 live young naturally. Thus, in vivo fertilisation is an effective technique to generate live offspring using slow-frozen oocytes in rabbits. PMID:24358281

Prenatal developmental toxicity testing of petroleum substances: Application of the mouse embryonic stem cell test (EST) to compare in vitro potencies with potencies observed in vivo.

PubMed

Kamelia, Lenny; Louisse, Jochem; de Haan, Laura; Rietjens, Ivonne M C M; Boogaard, Peter J

2017-10-01

Prenatal developmental toxicity (PDT) as observed with some petroleum substances (PS) has been associated with the presence of 3-7 ring polycyclic aromatic hydrocarbons (PAHs). In the present study, the applicability of ES-D3 cell differentiation assay of the EST to evaluate in vitro embryotoxicity potencies of PS and gas-to-liquid (GTL) products as compared to their in vivo potencies was investigated. DMSO-extracts of a range of PS, containing different amounts of PAHs, and GTL-products, which are devoid of PAHs, were tested in the ES-D3 cell proliferation and differentiation assays of the EST. The results show that PS inhibited the differentiation of ES-D3 cells into cardiomyocytes in a concentration-dependent manner at non-cytotoxic concentrations, and that their potency was proportional to their PAH content. In contrast, as expected, GTL-products did not inhibit ES-D3 cell viability or differentiation at all. The in vitro PDT potencies were compared to published in vivo PDT studies, and a good correlation was found between in vitro and in vivo results (R 2 =0.97). To conclude, our results support the hypothesis that PAHs are the primary inducers of the PDT in PS. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Optimised in vitro applicable loads for the simulation of lateral bending in the lumbar spine.

PubMed

Dreischarf, Marcel; Rohlmann, Antonius; Bergmann, Georg; Zander, Thomas

2012-07-01

In in vitro studies of the lumbar spine simplified loading modes (compressive follower force, pure moment) are usually employed to simulate the standard load cases flexion-extension, axial rotation and lateral bending of the upper body. However, the magnitudes of these loads vary widely in the literature. Thus the results of current studies may lead to unrealistic values and are hardly comparable. It is still unknown which load magnitudes lead to a realistic simulation of maximum lateral bending. A validated finite element model of the lumbar spine was used in an optimisation study to determine which magnitudes of the compressive follower force and bending moment deliver results that fit best with averaged in vivo data. The best agreement with averaged in vivo measured data was found for a compressive follower force of 700 N and a lateral bending moment of 7.8 Nm. These results show that loading modes that differ strongly from the optimised one may not realistically simulate maximum lateral bending. The simplified but in vitro applicable loading cannot perfectly mimic the in vivo situation. However, the optimised magnitudes are those which agree best with averaged in vivo measured data. Its consequent application would lead to a better comparability of different investigations. Copyright © 2012 IPEM. Published by Elsevier Ltd. All rights reserved.

Analysis of ToxCast data for food-relevant compounds by ...

EPA Pesticide Factsheets

The ToxCast program has generated a wealth of in vitro high throughput screening data, and best approaches for the interpretation and use of these data remain undetermined. We present case studies comparing the ToxCast and in vivo toxicity data for two food contact substances using the RISK21 approach. Available exposure data, toxicity data, and model predictions were analyzed for sodium pyrithione and dibutyltin dichloride. In-vitro to in-vivo extrapolation (IVIVE) was performed to determine oral equivalent doses (OEDs) for the ToxCast data bioactivity. For sodium pyrithione, calculated OEDs corresponded to doses that demonstrated toxicity in animal studies. For dibutyltin dichloride, calculated OEDs were below the doses that demonstrated toxicity in animals, but this was confounded by the conservative estimates used in the IVIVE calculations. These studies highlight the potential of the ToxCast approach while also indicating areas where additional data or predictive tools are needed. We present case studies comparing the ToxCast and in vivo toxicity data for two food contact substances using the RISK21 approach.

Cherenkov radiation imaging of beta emitters: in vitro and in vivo results

NASA Astrophysics Data System (ADS)

Spinelli, Antonello E.; Boschi, Federico; D'Ambrosio, Daniela; Calderan, Laura; Marengo, Mario; Fenzi, Alberto; Menegazzi, Marta; Sbarbati, Andrea; Del Vecchio, Antonella; Calandrino, Riccardo

2011-08-01

The main purpose of this work was to investigate both in vitro and in vivo Cherenkov radiation (CR) emission coming from 18F and 32P. The main difference between 18F and 32P is mainly the number of the emitted light photons, more precisely the same activity of 32P emits more CR photons with respect to 18F. In vitro results obtained by comparing beta counter measurements with photons average radiance showed that Cherenkov luminescence imaging (CLI) allows quantitative tracer activity measurements. In order to investigate in vivo the CLI approach, we studied an experimental xenograft tumor model of mammary carcinoma (BB1 tumor cells). Cherenkov in vivo dynamic whole body images of tumor bearing mice were acquired and the tumor tissue time activity curves reflected the well-known physiological accumulation of 18F-FDG in malignant tissues with respect to normal tissues. The results presented here show that it is possible to use conventional optical imaging devices for in vitro or in vivo study of beta emitters.

Comparative histological evaluation of new tyrosine-derived polymers and poly (L-lactic acid) as a function of polymer degradation.

PubMed

Hooper, K A; Macon, N D; Kohn, J

1998-09-05

Previous studies demonstrated that poly(DTE carbonate) and poly (DTE adipate), two tyrosine-derived polymers, have suitable properties for use in biomedical applications. This study reports the evaluation of the in vivo tissue response to these polymers in comparison to poly(L-lactic acid) (PLLA). Typically, the biocompatibility of a material is determined through histological evaluations as a function of implantation time in a suitable animal model. However, due to changes that can occur in the tissue response at different stages of the degradation process, a fixed set of time points is not ideal for comparative evaluations of materials having different rates of degradation. Therefore the tissue response elicited by poly(DTE carbonate), poly(DTE adipate), and PLLA was evaluated as a function of molecular weight. This allowed the tissue response to be compared at corresponding stages of degradation. Poly(DTE adipate) consistently elicited the mildest tissue response, as judged by the width and lack of cellularity of the fibrous capsule formed around the implant. The tissue response to poly(DTE carbonate) was mild throughout the 570 day study. However, the response to PLLA fluctuated as a function of the degree of degradation, exhibiting an increase in the intensity of inflammation as the implant began to lose mass. At the completion of the study, tissue ingrowth into the degrading and disintegrating poly(DTE adipate) implant was evident while no comparative ingrowth of tissue was seen for PLLA. The similarity of the in vivo and in vitro degradation rates of each polymer confirmed the absence of enzymatic involvement in the degradation process. A comparison of molecular weight retention, water uptake, and mass loss in vivo with two commonly used in vitro systems [phosphate-buffered saline (PBS) and simulated body fluid (SBF)] demonstrated that for the two tyrosine-derived polymers the in vivo results were equally well simulated in vitro with PBS and SBF. However, for PLLA the in vivo results were better simulated in vitro using PBS.

Is GABA neurotransmission enhanced in auditory thalamus relative to inferior colliculus?

PubMed Central

Cai, Rui; Kalappa, Bopanna I.; Brozoski, Thomas J.; Ling, Lynne L.

2013-01-01

Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the central auditory system. Sensory thalamic structures show high levels of non-desensitizing extrasynaptic GABAA receptors (GABAARs) and a reduction in the redundancy of coded information. The present study compared the inhibitory potency of GABA acting at GABAARs between the inferior colliculus (IC) and the medial geniculate body (MGB) using quantitative in vivo, in vitro, and ex vivo experimental approaches. In vivo single unit studies compared the ability of half maximal inhibitory concentrations of GABA to inhibit sound-evoked temporal responses, and found that GABA was two to three times (P < 0.01) more potent at suppressing MGB single unit responses than IC unit responses. In vitro whole cell patch-clamp slice recordings were used to demonstrate that gaboxadol, a δ-subunit selective GABAAR agonist, was significantly more potent at evoking tonic inhibitory currents from MGB neurons than IC neurons (P < 0.01). These electrophysiological findings were supported by an in vitro receptor binding assay which used the picrotoxin analog [3H]TBOB to assess binding in the GABAAR chloride channel. MGB GABAARs had significantly greater total open chloride channel capacity relative to GABAARs in IC (P < 0.05) as shown by increased total [3H]TBOB binding. Finally, a comparative ex vivo measurement compared endogenous GABA levels and suggested a trend towards higher GABA concentrations in MGB than in IC. Collectively, these studies suggest that, per unit GABA, high affinity extrasynaptic and synaptic GABAARs confer a significant inhibitory GABAAR advantage to MGB neurons relative to IC neurons. This increased GABA sensitivity likely underpins the vital filtering role of auditory thalamus. PMID:24155003

Concentric Rings K-Space Trajectory for Hyperpolarized 13C MR Spectroscopic Imaging

PubMed Central

Jiang, Wenwen; Lustig, Michael; Larson, Peder E.Z.

2014-01-01

Purpose To develop a robust and rapid imaging technique for hyperpolarized 13C MR Spectroscopic Imaging (MRSI) and investigate its performance. Methods A concentric rings readout trajectory with constant angular velocity is proposed for hyperpolarized 13C spectroscopic imaging and its properties are analyzed. Quantitative analyses of design tradeoffs are presented for several imaging scenarios. The first application of concentric rings on 13C phantoms and in vivo animal hyperpolarized 13C MRSI studies were performed to demonstrate the feasibility of the proposed method. Finally, a parallel imaging accelerated concentric rings study is presented. Results The concentric rings MRSI trajectory has the advantages of acquisition timesaving compared to echo-planar spectroscopic imaging (EPSI). It provides sufficient spectral bandwidth with relatively high SNR efficiency compared to EPSI and spiral techniques. Phantom and in vivo animal studies showed good image quality with half the scan time and reduced pulsatile flow artifacts compared to EPSI. Parallel imaging accelerated concentric rings showed advantages over Cartesian sampling in g-factor simulations and demonstrated aliasing-free image quality in a hyperpolarized 13C in vivo study. Conclusion The concentric rings trajectory is a robust and rapid imaging technique that fits very well with the speed, bandwidth, and resolution requirements of hyperpolarized 13C MRSI. PMID:25533653

Formulation and in vitro/in vivo evaluation of levodopa transdermal delivery systems.

PubMed

Lee, Kyung Eun; Choi, Yun Jung; Oh, Byu Ree; Chun, In Koo; Gwak, Hye Sun

2013-11-18

This study aims to investigate the feasibility of Levodopa transdermal delivery systems (TDSs). Levodopa TDSs were formulated using various vehicles and permeation enhancers, and in vitro permeation and in vivo pharmacokinetic studies were carried out. In the in vitro study, ester-type vehicles showed relatively high enhancing effects; propylene glycol monocaprylate and propylene glycol monolaurate showed the highest permeation fluxes from both solution and pressure sensitive adhesive (PSA) TDS formulations. Lag time was dramatically shortened with PSA TDS formulations as compared with solution formulations. In the in vivo study, the addition of fatty acids increased blood drug concentrations regardless of the kind or concentration of fatty acid; the AUCinf increased up to 8.7 times as compared with propylene glycol (PG) alone. PSA TDS containing 10% linoleic acid exhibited prolonged Tmax as compared with oral form. Total clearance of L-dopa from PSA TDSs was significantly lower than from oral form (up to 86.8 times). Especially, PSA TDS containing 10% linoleic acid (LOA) revealed 76.2 fold higher AUCinf than oral administration. Based on our results, the L-dopa PSA TDS containing PG with 10% LOA could be used as a good adjuvant therapy for Parkinson's disease patients who experience symptom fluctuation by L-dopa oral administration. Copyright © 2013 Elsevier B.V. All rights reserved.

In vitro and in vivo Efficacy of New Blue Light Emitting Diode Phototherapy Compared to Conventional Halogen Quartz Phototherapy for Neonatal Jaundice

PubMed Central

Chang, Yun Sil; Hwang, Jong Hee; Kwon, Hyuk Nam; Choi, Chang Won; Ko, Sun Young; Park, Won Soon; Shin, Son Moon

2005-01-01

High intensity light emitting diodes (LEDs) are being studied as possible light sources for the phototherapy of neonatal jaundice, as they can emit high intensity light of narrow wavelength band in the blue region of the visible light spectrum corresponding to the spectrum of maximal bilirubin absorption. We developed a prototype blue gallium nitride LED phototherapy unit with high intensity, and compared its efficacy to commercially used halogen quartz phototherapy device by measuring both in vitro and in vivo bilirubin photodegradation. The prototype device with two focused arrays, each with 500 blue LEDs, generated greater irradiance than the conventional device tested. The LED device showed a significantly higher efficacy of bilirubin photodegradation than the conventional phototherapy in both in vitro experiment using microhematocrit tubes (44±7% vs. 35±2%) and in vivo experiment using Gunn rats (30±9% vs. 16±8%). We conclude that high intensity blue LED device was much more effective than conventional phototherapy of both in vitro and in vivo bilirubin photodegradation. Further studies will be necessary to prove its clinical efficacy. PMID:15716604

Comparison of experimental models for predicting laser-tissue interaction from 3.8-micron lasers

NASA Astrophysics Data System (ADS)

Williams, Piper C. M.; Winston, Golda C. H.; Randolph, Don Q.; Neal, Thomas A.; Eurell, Thomas E.; Johnson, Thomas E.

2004-07-01

The purpose of this study was to evaluate the laser-tissue interactions of engineered human skin and in-vivo pig skin following exposure to a single 3.8 micron laser light pulse. The goal of the study was to determine if these tissues shared common histologic features following laser exposure that might prove useful in developing in-vitro and in-vivo experimental models to predict the bioeffects of human laser exposure. The minimum exposure required to produce gross morphologic changes following a four microsecond, pulsed skin exposure for both models was determined. Histology was used to compare the cellular responses of the experimental models following laser exposure. Eighteen engineered skin equivalents (in-vitro model), were exposed to 3.8 micron laser light and the tissue responses compared to equivalent exposures made on five Yorkshire pigs (in-vivo model). Representative biopsies of pig skin were taken for histologic evaluation from various body locations immediately, one hour, and 24 hours following exposure. The pattern of epithelial changes seen following in-vitro laser exposure of the engineered human skin and in-vivo exposure of pig skin indicated a common histologic response for this particular combination of laser parameters.

Chest drainage teaching and training for medical students. Use of a surgical ex vivo pig model.

PubMed

Tube, Milton Ignacio Carvalho; Netto, Fernando Antonio Campelo Spencer; Costa, Elaine; Lafayette, Daniell de Siqueira Araújo; Lima, George Augusto da Fonseca Carvalho Antunes; Menezes, Jamile Isabela Santos de; Aires, Vinicius Gueiros Buenos; Ferraz, Álvaro Antônio Bandeira; Campos, Josemberg Marins; Moraes, Fernando Ribeiro de

2016-05-01

Implement a constructivist approach in thoracic drainage training in surgical ex vivo pig models, to compare the acquisition of homogeneous surgical skills between medical students. Experimental study, prospective, transversal, analytical, controlled, three steps. Selection, training, evaluation. a) students without training in thoracic drainage; b) without exposure to constructivist methodology. 2) EXCLUSION CRITERIA: a) students developed surgical skills; b) a history of allergy. (N = 312). Two groups participated in the study: A and B. Lecture equal for both groups. Differentiated teaching: group A, descriptive and informative method; group B, learning method based on problems. A surgical ex vivo pig model for training the chest drain was created. Were applied pre and post-test, test goal-discursive and OSATS scale. Theoretical averages: Group A = 9.5 ± 0.5; Group B = 8.8 ± 1.1 (p = 0.006). Medium Practices: Group A = 22.8 ± 1.8; Group B = 23.0 ± 2.8 (p <0.001). Through the constructivist methodology implemented in the thoracic drainage training in surgical ex vivo pig models, has proven the acquisition of surgical skills homogeneous compared among medical students.

Thrombocytopathy leading to impaired in vivo haemostasis and thrombosis in platelet type von Willebrand disease.

PubMed

Kaur, Harmanpreet; Corscadden, Kathryn; Ware, Jerry; Othman, Maha

2017-02-28

Platelet defects due to hyper-responsive GPIbα causing enhanced VWF interaction, counter-intuitively result in bleeding rather than thrombosis. The historical explanation of platelet/VWF clearance fails to explain mechanisms of impaired haemostasis particularly in light of reported poor platelet binding to fibrinogen. This study aimed to evaluate the defects of platelets with hyper-responsive GPIbα and their contribution to impaired in vivo thrombosis. Using the PT-VWD mouse model, platelets from the hTg G233V were compared to control hTg WT mice. Platelets' pro-coagulant capacity was evaluated using flowcytometry assessment of P-selectin and annexin V. Whole blood platelet aggregation in response to ADP, collagen and thrombin was tested. Clot kinetics using laser injury thrombosis model and the effect of GPIbα inhibition in vivo using 6B4; a monoclonal antibody, were evaluated. Thrombin-induced platelet P-selectin and PS exposure were significantly reduced in hTg G233V compared to hTg WT and not significantly different when compared to unstimulated platelets. The hTg G233V platelets aggregated normally in response to collagen, and had a delayed response to ADP and thrombin, when compared to hTg WT platelets. Laser injury showed significant impairment of in vivo thrombus formation in hTg G233V compared to hTg WT mice. There was a significant lag in in vitro clot formation in turbidity assay but no impairment in thrombin generation was observed using thromboelastography. The in vivo inhibition of GPIbα facilitated new - unstable - clot formation but did not improve the lag. We conclude platelets with hyper-responsive GPIbα have complex intrinsic defects beyond the previously described mechanisms. Abnormal signalling through GPIbα and potential therapy using inhibitors require further investigations.

3D morphological analysis of the mouse cerebral vasculature: Comparison of in vivo and ex vivo methods

PubMed Central

Steinman, Joe; Koletar, Margaret M.; Stefanovic, Bojana; Sled, John G.

2017-01-01

Ex vivo 2-photon fluorescence microscopy (2PFM) with optical clearing enables vascular imaging deep into tissue. However, optical clearing may also produce spherical aberrations if the objective lens is not index-matched to the clearing material, while the perfusion, clearing, and fixation procedure may alter vascular morphology. We compared in vivo and ex vivo 2PFM in mice, focusing on apparent differences in microvascular signal and morphology. Following in vivo imaging, the mice (four total) were perfused with a fluorescent gel and their brains fructose-cleared. The brain regions imaged in vivo were imaged ex vivo. Vessels were segmented in both images using an automated tracing algorithm that accounts for the spatially varying PSF in the ex vivo images. This spatial variance is induced by spherical aberrations caused by imaging fructose-cleared tissue with a water-immersion objective. Alignment of the ex vivo image to the in vivo image through a non-linear warping algorithm enabled comparison of apparent vessel diameter, as well as differences in signal. Shrinkage varied as a function of diameter, with capillaries rendered smaller ex vivo by 13%, while penetrating vessels shrunk by 34%. The pial vasculature attenuated in vivo microvascular signal by 40% 300 μm below the tissue surface, but this effect was absent ex vivo. On the whole, ex vivo imaging was found to be valuable for studying deep cortical vasculature. PMID:29053753

Noninvasive Quantification of Retinal Microglia Using Widefield Autofluorescence Imaging.

PubMed

Kokona, Despina; Schneider, Nadia; Giannakaki-Zimmermann, Helena; Jovanovic, Joel; Ebneter, Andreas; Zinkernagel, Martin

2017-04-01

To validate widefield autofluorescence (AF) in vivo imaging of the retina in mice expressing green fluorescent protein (gfp) in microglia, and to monitor retinal microglia reconstitution in vivo after lethal irradiation and bone marrow transplantation. Transgenic Cx3cr1gfp/gfp and wildtype Balb/c mice were used in this study. A confocal scanning laser ophthalmoscope was used for AF imaging with a 55° and a widefield 102° lens. Intrasession reproducibility was assessed for each lens. To investigate reconstitution in vivo, bone marrow from Cx3cr1gfp/gfp mice was used to rescue lethally irradiated wildtype mice. Data were compared to confocal microscopy of retinal flat mounts. Both the 55° and the 102° lens produced high resolution images of retinal microglia with similar microglia density. However, compared to the 55° lens, the widefield 102° lens captured approximately 3.6 times more microglia cells (1515 ± 123 cells versus 445 ± 76 cells [mean ± SD], for 102° and 55°, respectively, P < 0.001). No statistical difference in the number of gfp positive cells within corresponding areas was observed within the same imaging session. Imaging of microglia reconstitution showed a similar time course compared to flat mount preparations with an excellent correlation between microglia cell numbers in AF and gfp-stained flat mounts (R = 0.92, P < 0.0001). Widefield AF imaging of mice with gfp expressing microglia can be used to quantify retinal microglia. In vivo microglia counts corresponded very well with ex vivo counts on retinal flat mounts. As such, AF imaging can largely replace ex vivo quantification.

Cerebral diffusion tensor imaging and in vivo proton magnetic resonance spectroscopy in patients with fulminant hepatic failure.

PubMed

Saksena, Sona; Rai, Vijan; Saraswat, Vivek Anand; Rathore, Ramkishore Singh; Purwar, Ankur; Kumar, Manoj; Thomas, M Albert; Gupta, Rakesh Kumar

2008-07-01

Cerebral edema is a major complication in patients with fulminant hepatic failure (FHF). The aim of this study was to evaluate the metabolite alterations and cerebral edema in patients with FHF using in vivo proton magnetic resonance spectroscopy (MRS) and diffusion tensor imaging, and to look for its reversibility in survivors. Ten FHF patients along with 10 controls were studied. Five of the 10 patients who recovered had a repeat imaging after three weeks. N-acetylaspartate, choline (Cho), glutamine (Gln), glutamine/glutamate (Glx), and myoinositol ratios were calculated with respect to creatine (Cr). Mean diffusivity (MD) and fractional anisotropy (FA) were calculated in different brain regions. Patients exhibited significantly increased Gln/Cr and Glx/Cr, and reduced Cho/Cr ratios, compared to controls. In the follow-up study, all metabolite ratios were normalized except Glx/Cr. Significantly decreased Cho/Cr were observed in deceased patients compared to controls. In patients, significantly decreased MD and FA values were observed in most topographical locations of the brain compared to controls. MD and FA values showed insignificant increase in the follow-up study compared to their first study. We conclude that the Cho/Cr ratio appears to be an in vivo marker of prognosis in FHF. Decreased MD values suggest predominant cytotoxic edema may be present. Persistence of imaging and MRS abnormalities at three weeks' clinical recovery suggests that metabolic recovery may take longer than clinical recovery in FHF patients.

Pressure profiles of sport compression stockings.

PubMed

Reich-Schupke, Stefanie; Surhoff, Stefan; Stücker, Markus

2016-05-01

While sport compression stockings (SCS) have become increasingly popular, there is no regulatory norm as exists for medical compression stockings (MCS). The objective of this pilot study was to compare five SCS with respect to their pressure profiles ex vivo and in vivo, and in relation to German standards for MCS (RAL norm). In vivo (10 competitive athletes; standardized procedure using the Kikuhime pressure monitor) and ex vivo (tested at the Hohenstein Institute) pressure profiles were tested for the following products: CEP Running Progressive Socks, Falke Running Energizing, Sigvaris Performance, X-Socks Speed Metal Energizer, and 2XU Compression Race Socks. Ex vivo ankle pressures of CEP (25.6 mmHg) and 2XU (23.2 mmHg) corresponded to class 2 MCS; that of Sigvaris (20.8 mmHg), to class 1 MCS. The remaining SCS achieved lower pressure values. The pressure gradients showed marked differences, and did not meet MCS standards. Average in vivo pressures were higher for 2XU, CEP, and Sigvaris than for Falke and X-Socks. However, in vivo values for all SCS were below those of class 1 MCS. None of the SCS showed the decreasing pressure gradient (from distal to proximal) required for MCS. In vivo and ex vivo pressure profiles of all SCS examined showed marked heterogeneity, and did not meet MCS standards. Consequently, the clinical and practical effects of SCS cannot be compared, either. It would therefore be desirable to establish a classification that allows for the categorization and comparison of various SCS as well as their selection based on individual preferences and needs (high vs. low pressure, progressive vs. degressive profile). © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

Liposomal Aloe vera trans-emulgel drug delivery of naproxen and nimesulide: A study

PubMed Central

Venkataharsha, Panuganti; Maheshwara, Ellutla; Raju, Y Prasanna; Reddy, Vayalpati Ashok; Rayadu, Bandugalla Sanjeev; Karisetty, Basappa

2015-01-01

Introduction: The present aim of this study was to formulate naproxen and nimesulide liposomal formulation for incorporation in Aloe vera transemulgel and to carry out in vitro and in vivo evaluation of the formulation. Material and Methods: A. vera gel was prepared and used as a gel base for formulation. Carbopol 934 is used as a gelling agent and Methyl paraben was used as a preservative for the formulation of the gel. Liposomes was formulated by using hydration method. The formulated naproxen and nimesulide liposomal formulation using A. vera trans-emul gel were evaluated for in vitro studies such as drug release, permeation study, and drug content and entrapment efficiency. Paw edema method in Wistar rats induced by carrageenan is used to study in vivo anti-inflammatory action. Result: From the in vitro studies such permeability drug release naproxen 65% (69.6), Nimesulide 65% (61.1), and commercial Nimsulide gel (60.82) at 240 min. In vivo data shows that formulated liposomal transemulgel formulation are superior in their efficacy compared to commercial and A. vera gel. The results are compared with the commercial formulations. Conclusion: From our results, it is concluded that the A. vera trans emul gel using nimesulide and naproxen liposomal formulation is stable and prepared gel base is effective for formulation with high drug release and drug content compared with commercial formulation with significant anti-inflammatory effect. PMID:25599030

In vitro and in vivo anthelmintic effects of Caesalpinia bonducella (L.) Roxb. leaf extract on Hymenolepis diminuta (Cestoda) and Syphacia obvelata (Nematoda)

PubMed Central

Gogoi, Shyamalima; Yadav, Arun K.

2016-01-01

Background: Leaves of Caesalpinia bonducella (L.) Roxb. have been traditionally used as an herbal remedy to treat the intestinal helminthic infections in traditional medicine of India. Aim: This study was undertaken to evaluate the potential in vitro and in vivo anthelmintic effects of C. bonducella leaf extract against Syphacia obvelata (Nematoda) and Hymenolepis diminuta (Cestoda). Materials and Methods: The in vitro anthelmintic activity of the extract was investigated on adult worms of S. obvelata (Nematoda) and H. diminuta (Cestoda) in terms of physical motility and mortality of parasites. The in vivo study was performed in H. diminuta-rat model and S. obvelata-mice model, by monitoring the egg per gram of feces count and worm count of animals following the treatment with different doses of plant extract. Results: The study recorded significant and dose-dependent anthelmintic effects of the extract on both the parasites. In the in vitro study, 30 mg/ml concentration of extract caused mortality of H. diminuta in 2.5 ± 0.2 h and S. obvelata in 3.57 ± 0.16 h. In the in vivo study, the extract showed a comparatively better efficacy on S. obvelata, where its 800 mg/kg dose revealed 93% reduction of worm load in mice, as compared to 85% worm load reduction of H. diminuta in rats. Conclusions: The findings suggest that leaf extract of C. bonducella possesses significant anthelmintic effects and supports its use as an anthelmintic in traditional medicine. This appears to be the first report of in vivo anthelmintic activity of C. bonducella against these parasites. PMID:27757275

Analysis of therapeutic growth hormone preparations: report of an interlaboratory collaborative study on growth hormone assay methodologies.

PubMed

Bristow, A F; Jeffcoate, S L

1992-09-01

Recombinant DNA-derived human growth hormone (somatotropin) is widely used to treat growth hormone-deficient children. The potency of this product is determined by in-vivo bioassay in hypophysectomized rats, which is imprecise, costly and invasive, and there have been suggestions that it could safely be replaced with in-vitro or physico-chemical alternatives. In this report we present the results of a collaborative study designed to test this proposal. Somatotropin was modified by mild or severe proteolysis, mild or severe oxidation or treatment at high pH, and compared in a multi-centre collaborative study with unmodified somatotropin or with dimerized somatotropin. Participating laboratories included manufacturers and national control laboratories, and pharmacopoeial bioassays were compared with in-house in-vitro and physico-chemical bioassays. Although performing adequately with untreated somatotropin, for degraded samples the in-vivo bioassays were relatively unresponsive to changes in the growth hormone molecule. In contrast, the physico-chemical assays, in particular the reverse-phase HPLC, performed with a high degree of selectivity. We conclude that in the case of somatotropin, the in-vivo bioassay can be removed from the routine product specification with an acceptable degree of security. This however does not obviate the requirement rigorously to demonstrate biological activity in-vivo during product development, nor may the conclusions of this study be applied to other therapeutic recombinant proteins without similar collaborative investigations.

Mobile Genetic Elements: In Silico, In Vitro, In Vivo

PubMed Central

Arkhipova, Irina R.; Rice, Phoebe A.

2016-01-01

Mobile genetic elements (MGEs), also called transposable elements (TEs), represent universal components of most genomes and are intimately involved in nearly all aspects of genome organization, function, and evolution. However, there is currently a gap between fast-paced TE discovery in silico, stimulated by exponential growth of comparative genomic studies, and a limited number of experimental models amenable to more traditional in vitro and in vivo studies of structural, mechanistic, and regulatory properties of diverse MGEs. Experimental and computational scientists came together to bridge this gap at a recent conference, “Mobile Genetic Elements: in silico, in vitro, in vivo,” held at the Marine Biological Laboratory (MBL) in Woods Hole, MA, USA. PMID:26822117

Taking the lead from our colleagues in medical education: the use of images of the in-vivo setting in teaching concepts of pharmaceutical science.

PubMed

Curley, Louise E; Kennedy, Julia; Hinton, Jordan; Mirjalili, Ali; Svirskis, Darren

2017-01-01

Despite pharmaceutical sciences being a core component of pharmacy curricula, few published studies have focussed on innovative methodologies to teach the content. This commentary identifies imaging techniques which can visualise oral dosage forms in-vivo and observe formulation disintegration in order to achieve a better understanding of in-vivo performance. Images formed through these techniques can provide students with a deeper appreciation of the fate of oral formulations in the body compared to standard disintegration and dissolution testing, which is conducted in-vitro. Such images which represent the in-vivo setting can be used in teaching to give context to both theory and experimental work, thereby increasing student understanding and enabling teaching of pharmaceutical sciences supporting students to correlate in-vitro and in-vivo processes.

Osteoconduction of impacted porous titanium particles with a calcium-phosphate coating is comparable to osteoconduction of impacted allograft bone particles: in vivo study in a nonloaded goat model.

PubMed

Walschot, Lucas H B; Aquarius, René; Schreurs, Barend W; Verdonschot, Nico; Buma, Pieter

2012-08-01

Impaction grafting restores bone defects in hip arthroplasty. Defects are reconstructed with bone particles (BoP) as substitute materials with adequate mechanical and biological properties are not yet available. Ceramic particles (CeP) have mechanical drawbacks as opposed to porous titanium particles (TiP). In this in vivo study, bone ingrowth and bone volume in coated and noncoated TiP were compared to porous biphasic calcium-phospate CeP and allograft BoP. Coatings consisted of silicated calcium-phosphate and carbonated apatite. Materials were implanted in goats and impacted in cylindrical defects (diameter 8 mm) in the cancellous bone of the femur. On the basis of fluorochrome labeling and histology, bone ingrowth distance was measured at 4, 8, and 12 weeks. Cross-sectional bone area was measured at 12 weeks. TiP created a coherent matrix of entangled particles. CeP pulverized and were noncoherent. Bone ingrowth in TiP improved significantly by the coatings to levels comparable to BoP and CeP. Cross-sectional bone area was smaller in CeP and TiP compared to BoP. The osteoconductive properties of impacted TiP with a calcium-phosphate coating are comparable to impacted allograft bone and impacted biphasic ceramics. A more realistic loaded in vivo study should prove that coated TiP is an attractive alternative to allograft bone. Copyright © 2012 Wiley Periodicals, Inc.

Knitted polylactide 96/4 L/D structures and scaffolds for tissue engineering: Shelf life, in vitro and in vivo studies

PubMed Central

Ellä, Ville; Annala, Tuija; Länsman, Satu; Nurminen, Manu; Kellomäki, Minna

2011-01-01

This study covers the whole production cycle, from biodegradable polymer processing to an in vivo tissue engineered construct. Six different biodegradable polylactide 96/4 L/D single jersey knits were manufactured using either four or eight multifilament fiber batches. The properties of those were studied in vitro for 42 weeks and in 0- to 3-year shelf life studies. Three types (Ø 12, 15 and 19 mm) of cylindrical scaffolds were manufactured from the knit, and the properties of those were studied in vitro for 48 weeks. For the Ø 15 mm scaffold type, mechanical properties were also studied in a one-year in vivo experiment. The scaffolds were implanted in the rat subcutis. All the scaffolds were g-irradiated prior to the studies. In vitro, all the knits lost 99% of their mechanical strength in 30 weeks. In the three-year follow up of shelf life properties, there was no decrease in the mechanical properties due to the storage time and only a 12% decrease in molecular weight. The in vitro and in vivo scaffolds lost their mechanical properties after 1 week. In the case of the in vivo samples, the mechanical properties were restored again, stepwise, by the presence of growing/maturing tissue between weeks 3 and 12. Faster degradation was observed with in vitro scaffolds compared to in vivo scaffolds during the one-year follow up. PMID:23507732

In vivo 3 T MR diffusion tensor imaging for detection of the fibre architecture of the human uterus: a feasibility and quantitative study

PubMed Central

Fiocchi, F; Nocetti, L; Siopis, E; Currà, S; Costi, T; Ligabue, G; Torricelli, P

2012-01-01

Objective The aim of this study was to investigate the feasibility of depicting fibre architecture of human uteri in vivo using 3 T MR diffusion tensor imaging (MR-DTI) with a three-dimensional (3D) tractography approach. Quantitative results were provided. Methods In vivo 3 T MR-DTI was performed on 30 volunteers (9 Caesarean delivery). Main diffusion directions reflecting the fibre orientation were determined using sensitivity-encoding single-shot echo planar imaging with diffusion-sensitised gradients (b=600 mm2 s−1) along 32 directions. A deterministic fibre-tracking algorithm was used to show in vivo fibre architecture, compared with ex vivo histological slides of cadaveric uteri. The number of fibres, the fibre density, the fractional anisotropy (FA) and the apparent diffusion coefficient (ADC) were measured in 13 volunteers. Results Anisotropy was found in most regions of normal uteri and the preferential order of uterine fibres depicted, consisting of two representative fibre directions: circular and longitudinal, as in ex vivo studies. Two-thirds of uteri with a Caesarean scar did not have the same orientation of fibres in the anterior isthmus when compared with non-scarred myometrium. Quantitative data were obtained from 13 volunteers: Caesarean-scarred uteri (n=5) showed lower fibre number and density in the scarred anterior isthmus than the nulliparous uteri (n=8). No significant differences were found in FA (0.42±0.02, 0.41±0.02; p=0.25) and ADC (1.82±0.18×10−3 mm2 s−1, 1.93±0.25×10−3 mm2 s−1; p=0.20). Conclusion Fibre architecture of the human uterus can be depicted in vivo using 3 T MR-DTI. Advances in knowledge 3 T MR-DTI can help to provide an in vivo insight of uterine anatomy non-invasively, especially in females with previous Caesarean surgery, in order to provide better management of subsequent deliveries. PMID:22744322

Cellular and molecular characterization of gametogenic progression in ex vivo cultured prepuberal mouse testes.

PubMed

Isoler-Alcaraz, J; Fernández-Pérez, D; Larriba, E; Del Mazo, J

2017-10-18

Recently, an effective testis culture method using a gas-liquid interphase, capable of differentiate male germ cells from neonatal spermatogonia to spermatozoa has been developed. Nevertheless, this methodology needs deep analyses that allow future experimental approaches in basic, pathologic and/or reprotoxicologic studies. Because of this, we characterized at cellular and molecular levels the entire in vitro spermatogenic progression, in order to understand and evaluate the characteristics that define the spermatogenic process in ex vivo cultured testes compared to the in vivo development. Testicular explants of CD1 mice aged 6 and 10 days post-partum were respectively cultured during 55 and 89 days. Cytological and molecular approaches were performed, analyzing germ cell proportion at different time culture points, meiotic markers immunodetecting synaptonemal complex protein SYCP3 by immunocytochemistry and the relative expression of different marker genes along the differentiation process by Reverse Transcription - quantitative Polymerase Chain Reaction. In addition, microRNA and piwi-interactingRNA profiles were also evaluated by Next Generation Sequencing and bioinformatic approaches. The method promoted and maintained the spermatogenic process during 89 days. At a cytological level we detected spermatogenic development delays of cultured explants compared to the natural in vivo process. The expression of different spermatogenic stages gene markers correlated with the proportion of different cell types detected in the cytological preparations. In vitro progression analysis of the different spermatogenic cell types, from both 6.5 dpp and 10.5 dpp testes explants, has revealed a relative delay in relation to in vivo process. The expression of the genes studied as biomarkers correlates with the cytologically and functional detected progression and differential expression identified in vivo. After a first analysis of deep sequencing data it has been observed that as long as cultures progress, the proportion of microRNAs declined respect to piwi-interactingRNAs levels that increased, showing a similar propensity than which happens in in vivo spermatogenesis. Our study allows to improve and potentially to control the ex vivo spermatogenesis development, opening new perspectives in the reproductive biology fields including male fertility.

Leaf water dynamics of Arabidopsis thaliana monitored in-vivo using terahertz time-domain spectroscopy

NASA Astrophysics Data System (ADS)

Castro-Camus, E.; Palomar, M.; Covarrubias, A. A.

2013-10-01

The declining water availability for agriculture is becoming problematic for many countries. Therefore the study of plants under water restriction is acquiring extraordinary importance. Botanists currently follow the dehydration of plants comparing the fresh and dry weight of excised organs, or measuring their osmotic or water potentials; these are destructive methods inappropriate for in-vivo determination of plants' hydration dynamics. Water is opaque in the terahertz band, while dehydrated biological tissues are partially transparent. We used terahertz spectroscopy to study the water dynamics of Arabidopsis thaliana by comparing the dehydration kinetics of leaves from plants under well-irrigated and water deficit conditions. We also present measurements of the effect of dark-light cycles and abscisic acid on its water dynamics. The measurements we present provide a new perspective on the water dynamics of plants under different external stimuli and confirm that terahertz can be an excellent non-contact probe of in-vivo tissue hydration.

Comparison of in-vivo skin models for near-infrared laser exposure

NASA Astrophysics Data System (ADS)

Eggleston, Thomas A.; Mitchell, Michael A.; Johnson, Thomas E.; Becker, Robert L., Jr.; Roach, William P.

1999-06-01

Current safety standards for lasers operating in the 1400 to 10,000 nm wavelength region are based on few observations at specific wavelengths using in vivo models that may not represent an accurate correlation to human integument. Based on experimental results conducted with Yorkshire pigs, these standards may not accurately reflect the potential for laser injury when humans are exposed to these wavelengths. It is our belief that one of the primary damage mechanisms involved in these laser injuries is due to energy absorption by skin pigmentation, or melanin. Qualitatively, Yorkshire pigs lack melanin in their skin when compared to a more highly pigmented animal, such as the Yucatan minipig. It is hypothesized that the Yucatan minipig is a more appropriate model for pigmented human skin. By comparing histologic samples taken from various locations on Yucatan minipigs and Yorkshire pigs, and comparing these to potential locations of skin exposure on humans, we present a discussion for the establishment of more appropriate locations for in vivo laser exposure studies.

Development, glycolytic activity, and viability of preimplantation mouse embryos subjected to different periods of glucose starvation.

PubMed

Leppens-Luisier, G; Sakkas, D

1997-03-01

After compaction, the preimplantation mouse embryo switches to a glucose-based metabolism, whereas for the 2- to 4-cell stage embryo, glucose can be inhibitory. In this study, we investigated the adaptability of preimplantation embryos to different periods of glucose starvation by culturing in vitro fertilized (IVF) and in vivo-fertilized 1-cell OF1 mouse embryos. Blastocysts obtained from exposure to glucose starvation for different periods of time were examined for the number of cells in the trophectoderm and inner cell mass, and for glycolytic activity and viability. A high percentage of blastocysts was obtained when 1-cell embryos fertilized in vitro or in vivo were cultured in M16 until the 2-cell stage, were transferred to M16 without glucose (M16-G) until the 4- or 8-cell stage, and then were transferred to fresh M16-G. When in vivo-fertilized 1-cell embryos were cultured to the 2-cell stage and then left in M16, less than 5% formed blastocysts compared to 26% of those transferred into M16-G. Blastocysts obtained when in vivo-fertilized 1-cell embryos were left in M16-G after the 2-cell stage, however, showed a significantly elevated glycolytic activity compared to those transferred to fresh M16 or M16-G medium at the 4- or 8-cell stage. Interestingly, even though these embryos displayed elevated glycolytic activity, they did not exhibit differences in the numbers of inner cell mass and trophectoderm cells or in viability compared to embryos cultured according to other protocols. Blastocysts from all cultured protocols had a significantly lower total cell number and a lower trophectoderm, but not inner cell mass, cell number compared to blastocysts developed in vivo. This study documents the metabolic adaptability of the preimplantation embryo by highlighting its ability to proceed with development and retain viability when challenged with glucose starvation at different periods.

In Vivo Evaluation of ¹⁸F-SiFAlin-Modified TATE: A Potential Challenge for ⁶⁸Ga-DOTATATE, the Clinical Gold Standard for Somatostatin Receptor Imaging with PET.

PubMed

Niedermoser, Sabrina; Chin, Joshua; Wängler, Carmen; Kostikov, Alexey; Bernard-Gauthier, Vadim; Vogler, Nils; Soucy, Jean-Paul; McEwan, Alexander J; Schirrmacher, Ralf; Wängler, Björn

2015-07-01

Radiolabeled peptides for tumor imaging with PET that can be produced with kits are currently in the spotlight of radiopharmacy and nuclear medicine. The diagnosis of neuroendocrine tumors in particular has been a prime example for the usefulness of peptides labeled with a variety of different radionuclides. Among those, (68)Ga and (18)F stand out because of the ease of radionuclide introduction (e.g., (68)Ga isotope) or optimal nuclide properties for PET imaging (slightly favoring the (18)F isotope). The in vivo properties of good manufacturing practice-compliant, newly developed kitlike-producible (18)F-SiFA- and (18)F-SiFAlin- (SiFA = silicon-fluoride acceptor) modified TATE derivatives were compared with the current clinical gold standard (68)Ga-DOTATATE for high-quality imaging of somatostatin receptor-bearing tumors. SiFA- and SiFAlin-derivatized somatostatin analogs were synthesized and radiolabeled using cartridge-based dried (18)F and purified via a C18 cartridge (radiochemical yield 49.8% ± 5.9% within 20-25 min) without high-performance liquid chromatography purification. Tracer lipophilicity and stability in human serum were tested in vitro. Competitive receptor binding affinity studies were performed using AR42J cells. The most promising tracers were evaluated in vivo in an AR42J xenograft mouse model by ex vivo biodistribution and in vivo PET/CT imaging studies for evaluation of their pharmacokinetic profiles, and the results were compared with those of the current clinical gold standard (68)Ga-DOTATATE. Synthetically easily accessible (18)F-labeled silicon-fluoride acceptor-modified somatostatin analogs were developed. They exhibited high binding affinities to somatostatin receptor-positive tumor cells (1.88-14.82 nM). The most potent compound demonstrated comparable pharmacokinetics and an even slightly higher absolute tumor accumulation level in ex vivo biodistribution studies as well as higher tumor standardized uptake values in PET/CT imaging than (68)Ga-DOTATATE in vivo. The radioactivity uptake in nontumor tissue was higher than for (68)Ga-DOTATATE. The introduction of the novel SiFA building block SiFAlin and of hydrophilic auxiliaries enables a favorable in vivo biodistribution profile of the modified TATE peptides, resulting in high tumor-to-background ratios although lower than those observed with (68)Ga-DOTATATE. As further advantage, the SiFA methodology enables a kitlike labeling procedure for (18)F-labeled peptides advantageous for routine clinical application. © 2015 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

``In Vivo'' Dosimetry in High Dose Rate Brachytherapy for Cervical Cancer Treatments

NASA Astrophysics Data System (ADS)

González-Azcorra, S. A.; Mota-García, A.; Poitevín-Chacón, M. A.; Santamaría-Torruco, B. J.; Rodríguez-Ponce, M.; Herrera-Martínez, F. P.; Gamboa de Buen, I.; Ruíz-Trejo, C.; Buenfil, A. E.

2008-08-01

In this prospective study, rectal dose was measured "in vivo" using TLD-100 crystals (3×3×1 mm3), and it has been compared to the prescribed dose. Measurements were performed in patients with cervical cancer classified in FIGO stages IB-IIIB and treated with high dose rate brachytherapy (HDR BT) at the Instituto Nacional de Cancerología (INCan).

Microwave ablation of ex vivo bovine tissues using a dual slot antenna with a floating metallic sleeve.

PubMed

Ibitoye, Ayo Zaccheaus; Nwoye, Ephraim Okeke; Aweda, Adebayo Moses; Oremosu, Ademola A; Anunobi, Chidozie Charles; Akanmu, Nurudeen Olanrewaju

2016-12-01

To study the efficiency of a dual slot antenna with a floating metallic sleeve on the ablation of different ex vivo bovine tissues. COMSOL Multiphysics® version 4.4 (Stockholm, Sweden), which is based on finite element methods (FEM), was used to design and simulate monopole and dual slot with sleeve antennas. Power, specific absorption rate (SAR), temperature and necrosis distributions in the selected tissues were determined using these antennas. Monopole and dual slot with sleeve antennas were designed, simulated, constructed and applied in this study based on a semi-rigid coaxial cable. Ex vivo experiments were performed on liver, lung, muscle and heart of bovine obtained from a public animal slaughter house. The microwave energy was delivered using a 2.45 GHz solid-state microwave generator at 40 W for 3, 5 and 10 min. Aspect ratio, ablation length and ablation diameter were also determined on ablated tissues and compared with simulated results. Student's t-test was used to compare the statistically significant difference between the performance of the two antennas. The dual slot antenna with sleeve produces localised microwave energy better than the monopole antenna in all ablated tissues using simulation and experimental validation methods. There were significant differences in ablation diameter and aspect ratio between the sleeve antenna and monopole antenna. Additionally, there were no significant differences between the simulation and experimental results. This study demonstrated that the dual slot antenna with sleeve produced larger ablation zones and higher sphericity index in ex vivo bovine tissues with minimal backward heating when compared with the monopole antenna.

In vivo imaging of human burn injuries with polarization-sensitive optical coherence tomography

NASA Astrophysics Data System (ADS)

Kim, Ki Hean; Pierce, Mark C.; Maguluri, Gopi; Park, B. Hyle; Yoon, Sang June; Lydon, Martha; Sheridan, Robert; de Boer, Johannes F.

2012-06-01

The accurate determination of burn depth is critical in the clinical management of burn wounds. Polarization-sensitive optical coherence tomography (PS-OCT) has been proposed as a potentially non-invasive method for determining burn depth by measuring thermally induced changes in the structure and birefringence of skin, and has been investigated in pre-clinical burn studies with animal models and ex vivo human skin. In this study, we applied PS-OCT to the in-vivo imaging of two pediatric burn patients. Deep and superficial burned skins along with contralateral controls were imaged in 3D. The imaging size was 8 mm×6 mm×2 mm in width, length, and depth in the air respectively, and the imaging time was approximately 6 s per volume. Superficially burned skins exhibited the same layered structure as the contralateral controls, but more visible vasculature and reduced birefringence compared to the contralateral controls. In contrast, a deeply burned skin showed loss of the layered structure, almost absent vasculature, and smaller birefringence compared to superficial burns. This study suggested the vasculature and birefringence as parameters for characterizing burn wounds.

MTR and In-vivo 1H-MRS studies on mouse brain with parkinson's disease

NASA Astrophysics Data System (ADS)

Yoon, Moon-Hyun; Kim, Hyeon-Jin; Chung, Jin-Yeung; Doo, Ah-Reum; Park, Hi-Joon; Kim, Seung-Nam; Choe, Bo-Young

2012-12-01

The aim of this study was to investigate whether the changes in the magnetization transfer ratio (MTR) histogram are related to specific characteristics of Parkinson's disease (PD) and to investigate whether the MTR histogram parameters are associated with neurochemical dysfunction by performing in vivo proton magnetic resonance spectroscopy (1H-MRS). MTR and in vivo 1H-MRS studies were performed on control mice (n = 10) and 1-methyl-1,2,3,6-tetrahydropyridine intoxicated mice (n = 10). All the MTR and in vivo 1H-MRS experiments were performed on a 9.4 T MRI/MRS system (Bruker Biospin, Germany) using a standard head coil. The protondensity fast spin echo (FSE) images and the T2-weighted spin echo (SE) images were acquired with no gap. Outer volume suppression (OVS), combined with the ultra-short echo-time stimulated echo acquisition mode (STEAM), was used for the localized in-vivo 1H-MRS. The quantitative analysis of metabolites was performed from the 1H spectra obtained in vivo on the striatum (ST) by using jMRUI (Lyon, France). The peak height of the MTR histograms in the PD model group was significantly lower than that in the control group (p < 0.05). The midbrain MTR values for volume were lower in the PD group than the control group(p < 0.05). The complex peak (Glx: glutamine+glutamate+ GABA)/creatine (Cr) ratio of the right ST in the PD group was significantly increased as compared to that of the control group. The present study revealed that the peak height of the MTR histogram was significantly decreased in the ST and substantia nigra, and a significant increase in the Gl x /Cr ratio was found in the ST of the PD group, as compared with that of the control group. These findings could reflect the early phase of neuronal dysfunction of neurotransmitters.

Arrhenius analysis of the relationship between hyperthermia and Hsp70 promoter activation: a comparison between ex vivo and in vivo data.

PubMed

Deckers, Roel; Debeissat, Christelle; Fortin, Pierre-Yves; Moonen, Chrit T W; Couillaud, Franck

2012-01-01

Tight regulation of gene expression in the region where therapy is necessary and for the duration required to achieve a therapeutic effect and to minimise systemic toxicity is very important for clinical applications of gene therapy. Hyperthermia in combination with a temperature sensitive heat shock protein (Hsp70) promoter presents a unique approach allowing non-invasive spatio-temporal control of transgene expression. In this study we investigated the in vivo and ex vivo relationship between temperature and duration of thermal stress with respect to the resulting gene expression using an Arrhenius analysis. A transgenic mouse expressing the luciferase reporter gene under the transcriptional control of a thermosensitive promoter was used to assure identical genotype for in vivo (mouse leg) and ex vivo (bone marrow mononuclear and embryonic fibroblast cells) studies. The mouse leg and cells were heated at different temperatures and different exposure times. Bioluminescence imaging and in vitro enzymatic assay were used to measure the resulting transgene expression. We showed that temperature-induced Hsp70 promoter activation was modulated by both temperature as well as duration of hyperthermia. The relationship between temperature and duration of hyperthermia and the resulting reporter gene expression can be modelled by an Arrhenius analysis for both in vivo as well as ex vivo. However, the increase in reporter gene expression after elevating the temperature of the thermal stress with 1°C is not comparable for in vivo and ex vivo situations. This information may be valuable for optimising clinical gene therapy protocols.

Brain energy metabolism and neuroinflammation in ageing APP/PS1-21 mice using longitudinal 18F-FDG and 18F-DPA-714 PET imaging.

PubMed

Takkinen, Jatta S; López-Picón, Francisco R; Al Majidi, Rana; Eskola, Olli; Krzyczmonik, Anna; Keller, Thomas; Löyttyniemi, Eliisa; Solin, Olof; Rinne, Juha O; Haaparanta-Solin, Merja

2017-08-01

Preclinical animal model studies of brain energy metabolism and neuroinflammation in Alzheimer's disease have produced conflicting results, hampering both the elucidation of the underlying disease mechanism and the development of effective Alzheimer's disease therapies. Here, we aimed to quantify the relationship between brain energy metabolism and neuroinflammation in the APP/PS1-21 transgenic mouse model of Alzheimer's disease using longitudinal in vivo 18 F-FDG and 18 F-DPA-714) PET imaging and ex vivo brain autoradiography. APP/PS1-21 (TG, n = 9) and wild type control mice (WT, n = 9) were studied longitudinally every third month from age 6 to 15 months with 18 F-FDG and 18 F-DPA-714 with a one-week interval between the scans. Additional TG (n = 52) and WT (n = 29) mice were used for ex vivo studies. In vivo, the 18 F-FDG SUVs were lower and the 18 F-DPA-714 binding ratios relative to the cerebellum were higher in the TG mouse cortex and hippocampus than in WT mice at age 12 to 15 months ( p < 0.05). The ex vivo cerebellum binding ratios supported the results of the in vivo 18 F-DPA-714 studies but not the 18 F-FDG studies. This longitudinal PET study demonstrated decreased energy metabolism and increased inflammation in the brains of APP/PS1-21 mice compared to WT mice.

Detecting condylar contact loss using single-plane fluoroscopy: a comparison with in vivo force data and in vitro bi-plane data.

PubMed

Prins, A H; Kaptein, B L; Banks, S A; Stoel, B C; Nelissen, R G H H; Valstar, E R

2014-05-07

Knee contact mechanics play an important role in knee implant failure and wear mechanics. Femoral condylar contact loss in total knee arthroplasty has been reported in some studies and it is considered to potentially induce excessive wear of the polyethylene insert.Measuring in vivo forces applied to the tibial plateau with an instrumented prosthesis is a possible approach to assess contact loss in vivo, but this approach is not very practical. Alternatively, single-plane fluoroscopy and pose estimation can be used to derive the relative pose of the femoral component with respect to the tibial plateau and estimate the distance from the medial and lateral parts of the femoral component towards the insert. Two measures are reported in the literature: lift-off is commonly defined as the difference in distance between the medial and lateral condyles of the femoral component with respect to the tibial plateau; separation is determined by the closest distance of each condyle towards the polyethylene insert instead of the tibia plateau.In this validation study, lift-off and separation as measured with single-plane fluoroscopy are compared to in vivo contact forces measured with an instrumented knee implant. In a phantom study, lift-off and separation were compared to measurements with a high quality bi-plane measurement.The results of the in vivo contact-force experiment demonstrate a large discrepancy between single-plane fluoroscopy and the in vivo force data: single-plane fluoroscopy measured up to 5.1mm of lift-off or separation, whereas the force data never showed actual loss of contact. The phantom study demonstrated that the single-plane setup could introduce an overestimation of 0.22mm±±0.36mm. Correcting the out-of-plane position resulted in an underestimation of medial separation by -0.20mm±±0.29mm.In conclusion, there is a discrepancy between the in vivo force data and single-plane fluoroscopic measurements. Therefore contact loss may not always be determined reliably by single plane fluoroscopy analysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

In vitro and in vivo anticandidal activities of alginate-enclosed chitosan–calcium phosphate-loaded Fe-bovine lactoferrin nanocapsules

PubMed Central

Leng, Khoo Miew; Vijayarathna, Soundararajan; Jothy, Subramanion L; Sasidharan, Sreenivasan; Kanwar, Jagat R

2018-01-01

Aim: To study the in vitro and in vivo anticandidal activity of nanocapsulated bovine lactoferrin. Materials & methods: In vitro and in vivo antimicrobial activities were conducted to study the anticandidal activities of nanocapsules (NCs). Results: The NCs showed good anticandidal activities. The disruption of cell wall and cell membrane was noted via microscopy studies. The NCs changed the normal growth profile of Candida albicans. NCs reduced the colony forming unit in kidney and blood samples. Histopathological examination showed better cell structure and coordination compared with untreated mice kidney. NCs also enhanced the natural killing properties of C. albicans by epithelial cells. Conclusion: NCs have effective anticandidal properties and have the potential as a therapeutic agent against candidiasis. PMID:29379633

Microwave Ablation: Comparison of Simultaneous and Sequential Activation of Multiple Antennas in Liver Model Systems.

PubMed

Harari, Colin M; Magagna, Michelle; Bedoya, Mariajose; Lee, Fred T; Lubner, Meghan G; Hinshaw, J Louis; Ziemlewicz, Timothy; Brace, Christopher L

2016-01-01

To compare microwave ablation zones created by using sequential or simultaneous power delivery in ex vivo and in vivo liver tissue. All procedures were approved by the institutional animal care and use committee. Microwave ablations were performed in both ex vivo and in vivo liver models with a 2.45-GHz system capable of powering up to three antennas simultaneously. Two- and three-antenna arrays were evaluated in each model. Sequential and simultaneous ablations were created by delivering power (50 W ex vivo, 65 W in vivo) for 5 minutes per antenna (10 and 15 minutes total ablation time for sequential ablations, 5 minutes for simultaneous ablations). Thirty-two ablations were performed in ex vivo bovine livers (eight per group) and 28 in the livers of eight swine in vivo (seven per group). Ablation zone size and circularity metrics were determined from ablations excised postmortem. Mixed effects modeling was used to evaluate the influence of power delivery, number of antennas, and tissue type. On average, ablations created by using the simultaneous power delivery technique were larger than those with the sequential technique (P < .05). Simultaneous ablations were also more circular than sequential ablations (P = .0001). Larger and more circular ablations were achieved with three antennas compared with two antennas (P < .05). Ablations were generally smaller in vivo compared with ex vivo. The use of multiple antennas and simultaneous power delivery creates larger, more confluent ablations with greater temperatures than those created with sequential power delivery. © RSNA, 2015.

Impact of Diesel Exhaust Particles on Th2 Response in the Lung in Asthmatic Mice

PubMed Central

Inoue, Ken-ichiro; Koike, Eiko; Yanagisawa, Rie; Takano, Hirohisa

2008-01-01

Although it has been accepted that pulmonary exposure to diesel exhaust particles (DEP), representative constituents in particulate matter of mass median aerodynamic diameter < or 2.5 µm (PM2.5), exacerbates murine allergic asthma, the in vivo effects of DEP on their cellular events in the context of allergen-specific Th response have never been examined. The aim of this study is to elucidate whether in vivo repetitive exposure to DEP combined with allergen (ovalbumin) facilitate allergen-specific Th response in the lung using a simple ex vivo assay system. As a result, repetitive pulmonary exposure to DEP in vivo, if combined with allergen, amplifies ex vivo allergen-specific Th2 response in the lung compared to that to allergen alone, characterized by high levels of interleukin (IL)-4 and IL-5. The result suggests that in asthmatic subjects, DEP promote Th2-prone milieu in the lung, which additively/synergistically augment asthma pathophysiology in vivo. PMID:19015755

Comparative Effect of Quercetin and Quercetin-3-O-β-d-Glucoside on Fibrin Polymers, Blood Clots, and in Rodent Models.

PubMed

Choi, Jun-Hui; Kim, Kyung-Je; Kim, Seung

2016-11-01

The present study evaluates the in vitro, in vivo, and ex vivo antithrombotic and anticoagulant effect of two flavonoids: quercetin and quercetin-3-O-β-d-glucoside (isoquercetin). The present results have shown that quercetin and isoquercetin inhibit the enzymatic activity of thrombin and FXa and suppress fibrin clot formation and blood clotting. The prolongation effect of quercetin and isoquercetin against epinephrine and collagen-induced platelet activation may have been caused by intervention in intracellular signaling pathways including coagulation cascade and aggregation response on platelets and blood. The in vivo and ex vivo anticoagulant efficacy of quercetin and isoquercetin was evaluated in thrombin-induced acute thromboembolism model and in ICR mice. Our findings showed that in vitro and in vivo inhibitory effects of quercetin were slightly higher than that of quercetin glucoside, whereas in vitro and ex vivo anticoagulant effects of quercetin were weaker than that of quercetin glucoside because of their structural characteristics. © 2016 Wiley Periodicals, Inc.

Feasibility study of entrance in vivo dose measurements with mailed thermoluminescence detectors.

PubMed

Swinnen, Ans; Verstraete, Jan; Huyskens, Dominique Pierre

2004-10-01

The aim of this work is to set-up mailed entrance in vivo dosimetry by means of thermoluminescence dosimeters (TLDs) in the form of LiF powder in order to assess the overall accuracy of patient treatment delivery by comparing the doses delivered to patients with the doses calculated by the treatment planning system (TPS) in different institutions. Two millimeter thick copper (for 6 MV photon beams) and 1.3 mm thick aluminium (for (60)Co gamma beams) build-up caps are developed. The characteristics of these build-up caps are tested by phantom measurements: the response of the TLD inside the build-up cap is compared to the ionisation chamber (IC) signal in the same irradiation conditions. A pilot study using the copper build-up cap is performed on 8 patients, treated with a 6 MV photon beam at the radiotherapy department of the University Hospital of Leuven. Additionally, a first run of mailed entrance in vivo dosimetry is performed by 18 radiotherapy centres in Europe. For 80 different phantom set-ups using copper and aluminium build-up caps, the mean TLD dose compared to the IC dose is 0.993+/-0.015 (1SD). Regarding the patient measurements in the radiotherapy department of the University Hospital of Leuven, the mean ratio of the measured entrance dose (TLD) to the entrance dose calculated by the TPS, is equal to 0.986+/-0.017 (1SD) (N=8), after correction of an error detected in one of the patient treatments. For the 18 radiotherapy centres participating in the mailed in vivo TLD study, the mean measured versus stated entrance dose for patients treated in a (60)Co and 6 MV photon beam is 1.004+/-0.021 (1SD) (N=143). From the results, it can be deduced that the build-up caps and the proposed calibration methodology allow the use of TLD in the form of powder to be applied in large scale in vivo dose audits.

Lister vaccine strain of vaccinia virus armed with the endostatin-angiostatin fusion gene: an oncolytic virus superior to dl1520 (ONYX-015) for human head and neck cancer.

PubMed

Tysome, James R; Wang, Pengju; Alusi, Ghassan; Briat, Arnaud; Gangeswaran, Rathi; Wang, Jiwei; Bhakta, Vipul; Fodor, Istvan; Lemoine, Nick R; Wang, Yaohe

2011-09-01

Oncolytic viral therapy represents a promising strategy for the treatment of head and neck squamous cell carcinoma (HNSCC), with dl1520 (ONYX-015) the most widely used oncolytic adenovirus in clinical trials. This study aimed to determine the effectiveness of the Lister vaccine strain of vaccinia virus as well as a vaccinia virus armed with the endostatin-angiostatin fusion gene (VVhEA) as a novel therapy for HNSCC and to compare them with dl1520. The potency and replication of the Lister strain and VVhEA and the expression and function of the fusion protein were determined in human HNSCC cells in vitro and in vivo. Finally, the efficacy of VVhEA was compared with dl1520 in vivo in a human HNSCC model. The Lister vaccine strain of vaccinia virus was more effective than the adenovirus against all HNSCC cell lines tested in vitro. Although the potency of VVhEA was attenuated in vitro, the expression and function of the endostatin-angiostatin fusion protein was confirmed in HNSCC models both in vitro and in vivo. This novel vaccinia virus (VVhEA) demonstrated superior antitumor potency in vivo compared with both dl1520 and the control vaccinia virus. This study suggests that the Lister strain vaccinia virus armed with an endostatin-angiostatin fusion gene may be a potential therapeutic agent for HNSCC.

In vitro and in vivo studies of pharmacokinetics and antitumor efficacy of D07001-F4, an oral gemcitabine formulation.

PubMed

Hao, Wei-Hua; Wang, Jong-Jing; Hsueh, Shu-Ping; Hsu, Pei-Jing; Chang, Li-Chien; Hsu, Chang-Shan; Hsu, Kuang-Yang

2013-02-01

The chemotherapy agent gemcitabine is currently administered intravenously because the drug has poor oral bioavailability. In order to assess the pharmacokinetics and antitumor activity of D07001-F4, a new self-microemulsifying oral drug delivery system preparation of gemcitabine, this study was performed to compare the effect of D07001-F4 with administered gemcitabine in vitro and in vivo. D07001-F4 pharmacokinetics was examined by evaluation of in vitro deamination of D07001-F4 and gemcitabine hydrochloride by recombinant human cytidine deaminase (rhCDA) and in vivo evaluation of D07001-F4 pharmacokinetics in mice. Antitumor activity was evaluated by comparing the effect of D07001-F4 and gemcitabine hydrochloride in inhibiting growth in nine cancer cell lines and by examining the effect of D07001-F4 and gemcitabine in two xenograft tumor models in mice. In vitro deamination of D07001-F4 by rhCDA was 3.3-fold slower than deamination of gemcitabine hydrochloride. Growth inhibition by D07001-F4 of 7 of the 8 cancer cell lines was increased compared with that seen with gemcitabine hydrochloride, and D07001-F4 inhibited the growth of pancreatic and colon cancer xenografts. In vivo pharmacokinetics showed the oral bioavailability of D07001-F4 to be 34%. D07001-F4 was effective against several cancer types, was metabolized more slowly than gemcitabine hydrochloride, and exhibited enhanced oral bioavailability.

Influence of peptide dendrimers and sonophoresis on the transdermal delivery of ketoprofen.

PubMed

Manikkath, Jyothsna; Hegde, Aswathi R; Kalthur, Guruprasad; Parekh, Harendra S; Mutalik, Srinivas

2017-04-15

The aim of this study was to determine the individual and combined effects of peptide dendrimers and low frequency ultrasound on the transdermal permeation of ketoprofen. Arginine terminated peptide dendrimers of varying charges (4 + , 8 + and 16 + , named as A4. A8 and A16 respectively) were synthesized and characterized. Ketoprofen was subjected to passive, peptide dendrimer-assisted and sonophoretic permeation studies (with and without dendrimer application) across Swiss albino mouse skin, both in vitro and in vivo. The studies revealed that the synthesized peptide dendrimers considerably increased the transdermal permeation of ketoprofen and displayed enhancement ratios of up to 3.25 (with A16 dendrimer), compared to passive diffusion of drug alone in vitro. Moreover, the combination of peptide dendrimer treatment and ultrasound application worked in synergy and gave enhancement ratios of up to 1369.15 (with ketoprofen-A16 dendrimer complex). In vivo studies demonstrated that dendrimer and ultrasound-assisted permeation of drug achieved much higher plasma concentration of drug, compared to passive diffusion. Comparison of transdermal and oral absorption studies revealed that transdermal administration of ketoprofen with A8 dendrimer showed comparable absorption and plasma drug levels with oral route. The excised mouse skin after in vivo permeation study with dendrimers and ultrasound did not show major toxic reactions. This study demonstrates that arginine terminated peptide dendrimers combined with sonophoresis can effectively improve the transdermal permeation of ketoprofen. Copyright © 2017 Elsevier B.V. All rights reserved.

Docosahexaenoic acid, G protein-coupled receptors, and melanoma: is G protein-coupled receptor 40 a potential therapeutic target?

PubMed

Nehra, Deepika; Pan, Amy H; Le, Hau D; Fallon, Erica M; Carlson, Sarah J; Kalish, Brian T; Puder, Mark

2014-05-15

To determine the effect of docosahexaenoic acid (DHA) on the growth of human melanoma in vitro and in vivo and to better understand the potential role of the G protein-coupled receptors (GPRs) in mediating this effect. For in vitro studies, human melanoma and control fibroblast cells were treated with DHA and TAK-875 (selective GPR40 agonist) and a cell viability assay was performed to determine cell counts. A murine subcutaneous xenograft model of human melanoma was used to test the effect of dietary treatment with an omega-3 fatty acid (FA) rich diet compared with an omega-6 FA rich diet on the growth of human melanoma in vivo. A similar animal model was used to test the effect of oral TAK-875 on the growth of established melanoma tumors in vivo. DHA has an inhibitory effect on the growth of human melanoma both in vitro and in vivo. Tumors from animals on the omega-3 FA rich diet were 69% smaller in weight (P = 0.005) and 76% smaller in volume compared with tumors from animals on the omega-6 FA rich diet. TAK-875 has an inhibitory effect on the growth of human melanoma both in vitro and in vivo. Tumors from animals treated with TAK-875 were 46% smaller in weight (P = 0.07), 62% smaller in volume (P = 0.03), and grew 77% slower (P = 0.04) compared with the placebo group. DHA and TAK-875 have a profound and selective inhibitory effect on the growth of human melanoma both in vitro and in vivo. Copyright © 2014 Elsevier Inc. All rights reserved.

Recent Advances in In Vivo Genotoxicity Testing: Prediction of Carcinogenic Potential Using Comet and Micronucleus Assay in Animal Models

PubMed Central

Kang, Seung Hun; Kwon, Jee Young; Lee, Jong Kwon; Seo, Young Rok

2013-01-01

Genotoxic events have been known as crucial step in the initiation of cancer. To assess the risk of cancer, genotoxicity assays, including comet, micronucleus (MN), chromosomal aberration, bacterial reverse, and sister chromatid exchange assay, can be performed. Compared with in vitro genotoxicity assay, in vivo genotoxicity assay has been used to verify in vitro assay result and definitely provide biological significance for certain organs or cell types. The comet assay can detect DNA strand breaks as markers of genotoxicity. Methods of the in vivo comet assay have been established by Japanese Center for the Validation of Alternative Methods (JaCVAM) validation studies depending on tissue and sample types. The MN can be initiated by segregation error and lagging acentric chromosome fragment. Methods of the in vivo MN assay have been established by Organization for Economic Co-operation and Development (OECD) test guidelines and many studies. Combining the in vivo comet and MN assay has been regarded as useful methodology for evaluating genetic damage, and it has been used in the assessment of potential carcinogenicity by complementarily presenting two distinct endpoints of the in vivo genotoxicity individual test. Few studies have investigated the quantitative relation between in vivo genotoxicity results and carcinogenicity. Extensive studies emphasizes that positive correlation is detectable. This review summarizes the results of the in vivo comet and MN assays that have investigated the genotoxicity of carcinogens as classified by the International Agency for Research on Cancer (IARC) carcinogenicity database. As a result, these genotoxicity data may provide meaningful information for the assessment of potential carcinogenicity and for implementation in the prevention of cancer. PMID:25337557

Plasma and Cavitation Dynamics during Pulsed Laser Microsurgery in vivo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hutson, M. Shane; Ma Xiaoyan

We compare the plasma and cavitation dynamics underlying pulsed laser microsurgery in water and in fruit fly embryos (in vivo)--specifically for nanosecond pulses at 355 and 532 nm. We find two key differences. First, the plasma-formation thresholds are lower in vivo --especially at 355 nm--due to the presence of endogenous chromophores that serve as additional sources for plasma seed electrons. Second, the biological matrix constrains the growth of laser-induced cavitation bubbles. Both effects reduce the disrupted region in vivo when compared to extrapolations from measurements in water.

Vascular smooth muscle cell polyploidy and cardiomyocyte hypertrophy due to chronic NOS inhibition in vivo.

PubMed

Devlin, A M; Brosnan, M J; Graham, D; Morton, J J; McPhaden, A R; McIntyre, M; Hamilton, C A; Reid, J L; Dominiczak, A F

1998-01-01

To assess the vascular and cardiac response to NO (nitric oxide) synthase (NOS) blockade in vivo, Wistar-Kyoto rats (WKY) were treated for 3 wk with NG-nitro-L-arginine methyl ester (L-NAME; 10 mg.kg-1.day-1). L-NAME treatment induced hypertension that was associated with increased plasma renin activity. Flow cytometry cell cycle DNA analysis showed that aortic vascular smooth muscle cells (VSMC) from L-NAME-treated WKY had a significantly higher polyploid population compared with WKY controls. Using organ bath experiments, we have shown that aortic rings from L-NAME-treated WKY have an increased contractile response to phenylephrine and impaired relaxation to carbachol compared with control rings. NOS blockade in vivo caused a significant increase in cardiac and left ventricular hypertrophy. Northern mRNA analysis of the myocardium showed that L-NAME treatment caused reexpression of the fetal skeletal alpha-actin isoform without alterations in collagen type I expression, a pattern indicating true hypertrophy of the cardiomyocytes. These studies provide further insight to confirm that NO deficiency in vivo results in the development of vascular and cardiac hypertrophy.

In vitro, ex vivo and in vivo models: A comparative analysis of Paracoccidioides spp. proteomic studies.

PubMed

Parente-Rocha, Juliana Alves; Tomazett, Mariana Vieira; Pigosso, Laurine Lacerda; Bailão, Alexandre Melo; Ferreira de Souza, Aparecido; Paccez, Juliano Domiraci; Baeza, Lilian Cristiane; Pereira, Maristela; Silva Bailão, Mirelle Garcia; Borges, Clayton Luiz; Maria de Almeida Soares, Célia

2018-06-01

Members of the Paracoccidioides complex are human pathogens that infect different anatomic sites in the host. The ability of Paracoccidioides spp. to infect host niches is putatively supported by a wide range of virulence factors, as well as fitness attributes that may comprise the transition from mycelia/conidia to yeast cells, response to deprivation of micronutrients in the host, expression of adhesins on the cell surface, response to oxidative and nitrosative stresses, as well as the secretion of hydrolytic enzymes in the host tissue. Our understanding of how those molecules can contribute to the infection establishment has been increasing significantly, through the utilization of several models, including in vitro, ex vivo and in vivo infection in animal models. In this review we present an update of our understanding on the strategies used by the pathogen to establish infection. Our results were obtained through a comparative proteomic analysis of Paracoccidioides spp. in models of infection. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

Convection Enhanced Delivery: A Comparison of infusion characteristics in ex vivo and in vivo non-human primate brain tissue.

PubMed

Miranpuri, Gurwattan; Hinchman, Angelica; Wang, Anyi; Schomberg, Dominic; Kubota, Ken; Brady, Martin; Raghavan, Raghu; Bruner, Kevin; Brodsky, Ethan; Block, Walter; Grabow, Ben; Raschke, Jim; Alexander, Andrew; Ross, Chris; Simmons, Heather; Sillay, Karl

2013-07-01

Convection enhanced delivery (CED) is emerging as a promising infusion toolto facilitate delivery of therapeutic agents into the brain via mechanically controlled pumps. Infusion protocols and catheter design have an important impact on delivery. CED is a valid alternative for systemic administration of agents in clinical trials for cell and gene therapies. Where gel and ex vivo models are not sufficient in modeling the disease, in vivo models allow researchers to better understand the underlying mechanisms of neuron degeneration, which is helpful in finding novel approaches to control the process or reverse the progression. Determining the risks, benefits, and efficacy of new gene therapies introduced via CED will pave a way to enter human clinical trial. The objective of this study is to compare volume distribution (Vd)/ volume infused (Vi) ratios and backflow measurements following CED infusions in ex vivo versus in vivo non-human primate brain tissue, based on infusion protocols developed in vitro. In ex vivo infusions, the first brain received 2 infusions using a balloon catheter at rates of 1 μL/min and 2 μL/min for 30 minutes. The second and third brains received infusions using a valve-tip (VT) catheter at 1 μL/min for 30 minutes. The fourth brain received a total of 45 μL infused at a rate of 1 μL/min for 15 minutes followed by 2 μL/min for 15 minutes. Imaging was performed (SPGR FA34) every 3 minutes. In the in vivo group, 4 subjects received a total of 8 infusions of 50 μL. Subjects 1 and 2 received infusions at 1.0 μL/min using a VT catheter in the left hemisphere and a smart-flow (SF) catheter in the right hemisphere. Subjects 3 and 4 each received 1 infusion in the left and right hemisphere at 1.0 μL/min. MRI calculations of Vd/Vi did not significantly differ from those obtained on post-mortem pathology. The mean measured Vd/Vi of in vivo (5.23 + /-1.67) compared to ex vivo (2.17 + /-1.39) demonstrated a significantly larger Vd/Vi for in vivo by 2.4 times (p = 0.0017). We detected higher ratios in the in vivo subjects than in ex vivo. This difference could be explained by the extra cellular space volume fraction. Studies evaluating backflow and morphology use in vivo tissue as a medium are recommended. Further investigation is warranted to evaluate the role blood pressure and heart rate may play in human CED clinical trials.

Evaluation of the in vivo disintegration of solid dosage forms of a bile acid sequestrant in dogs using gamma-scintigraphy and correlation to in vitro disintegration.

PubMed

Hussain, Munir A; Chang, Rong-Kun; Sandefer, Erik; Page, Richard C; Digenis, George A

2003-03-01

[corrected] To evaluate the in vivo disintegration behavior of tablets and capsules of a bile acid sequestrant, DMP 504, in beagle dogs and to assess the significance of the in vitro disintegration of the dosage forms on subsequent in vivo behavior in order to draw possible in vitro-in vivo correlations. Tablet and capsule formulations of a bile acid sequestrant, DMP 504, were formulated with samarium oxide and neutron activated to produce radioactive 53Sm to noninvasively evaluate their in vivo behavior in beagle dogs by gamma-scintigraphy. A four-way crossover design was completed (n = 4) in which (a) tablets from two different batches were administered under the fasted condition and manufactured using different lots of drug substance where one batch exhibited relatively faster in vitro disintegration time (30 min) than the other tablet batch, which resulted in slower disintegration (45 min), (b) a capsule formulation was administered to fasted beagles, and (c) the tablet having slower in vitro disintegration was also administered in the fed state, and its in vivo disintegration was compared to that observed in the fasted state. Tablets manufactured using a lot of DMP 504 having relatively fast in vitro disintegration (approximately 30 min) resulted in relatively rapid in vivo disintegration time (15 min) in the fasted condition. This in vivo disintegration time was comparable to the in vivo disintegration of the capsules (17 min) even though the in vitro capsule disintegration time was considerably faster (2 min). Tablets prepared using a drug substance that provided a longer in vitro disintegration time (approximately 45 min) resulted in a slower in vivo disintegration (63 min). There was no difference observed in the in vivo disintegration behavior in fasted and fed dogs for the tablets that provided slower in vitro disintegration. In vivo disintegration of tablets of the bile acid sequestrant DMP 504 correlated with in vitro disintegration times. Gamma-Scintigraphy continues to be a good tool to use during early stages of product development to investigate in vivo performance of dosage forms. The results of this study provided evidence that the physical chemical specifications of the drug substance may not always be indicative of in vitro or in vivo performance of tablet dosage form, even when formulation and process are not changed.

Evaluation of the in vivo and ex vivo optical properties in a mouse ear model

NASA Astrophysics Data System (ADS)

Salomatina, E.; Yaroslavsky, A. N.

2008-06-01

Determination of in vivo optical properties is a challenging problem. Absorption and scattering measured ex vivo are often used for in vivo applications. To investigate the validity of this approach, we have obtained and compared the optical properties of mouse ears in vivo and ex vivo in the spectral range from 370 to 1650 nm. Integrating sphere spectrophotometry in combination with the inverse Monte Carlo technique was employed to determine absorption coefficients, μa, scattering coefficients, μs, and anisotropy factors, g. Two groups of mice were used for the study. The first group was measured in vivo and ex vivo within 5-10 min post mortem. The second group was measured in vivo and ex vivo every 24 h for up to 72 h after sacrifice. Between the measurements the tissues were kept at 4 °C wrapped in a gauze moistened with saline solution. Then the specimens were frozen at -25 °C for 40 min, thawed and measured again. The results indicate that the absorption coefficients determined in vivo and ex vivo within 5-10 min post mortem differed considerably only in the spectral range dominated by hemoglobin. These changes can be attributed to rapid deoxygenation of tissue and blood post mortem. Absorption coefficients determined ex vivo up to 72 h post mortem decreased gradually with time in the spectral regions dominated by hemoglobin and water, which can be explained by the continuing loss of blood. Absorption properties of the frozen-thawed ex vivo tissues showed increase in oxygenation, which is likely caused by the release of hemoglobin from hemolyzed erythrocytes. Scattering of the ex vivo tissues decreased gradually with time in the entire spectral range due to the continuing loss of blood and partial cell damage. Anisotropy factors did not change considerably.

Evaluation of the in vivo and ex vivo optical properties in a mouse ear model.

PubMed

Salomatina, E; Yaroslavsky, A N

2008-06-07

Determination of in vivo optical properties is a challenging problem. Absorption and scattering measured ex vivo are often used for in vivo applications. To investigate the validity of this approach, we have obtained and compared the optical properties of mouse ears in vivo and ex vivo in the spectral range from 370 to 1650 nm. Integrating sphere spectrophotometry in combination with the inverse Monte Carlo technique was employed to determine absorption coefficients, mu(a), scattering coefficients, mu(s), and anisotropy factors, g. Two groups of mice were used for the study. The first group was measured in vivo and ex vivo within 5-10 min post mortem. The second group was measured in vivo and ex vivo every 24 h for up to 72 h after sacrifice. Between the measurements the tissues were kept at 4 degrees C wrapped in a gauze moistened with saline solution. Then the specimens were frozen at -25 degrees C for 40 min, thawed and measured again. The results indicate that the absorption coefficients determined in vivo and ex vivo within 5-10 min post mortem differed considerably only in the spectral range dominated by hemoglobin. These changes can be attributed to rapid deoxygenation of tissue and blood post mortem. Absorption coefficients determined ex vivo up to 72 h post mortem decreased gradually with time in the spectral regions dominated by hemoglobin and water, which can be explained by the continuing loss of blood. Absorption properties of the frozen-thawed ex vivo tissues showed increase in oxygenation, which is likely caused by the release of hemoglobin from hemolyzed erythrocytes. Scattering of the ex vivo tissues decreased gradually with time in the entire spectral range due to the continuing loss of blood and partial cell damage. Anisotropy factors did not change considerably.

Diagnosing Cervical Neoplasia in Rural Brazil Using a Mobile Van Equipped with In Vivo Microscopy: A Cluster-Randomized Community Trial.

PubMed

Hunt, Brady; Fregnani, José Humberto Tavares Guerreiro; Schwarz, Richard A; Pantano, Naitielle; Tesoni, Suelen; Possati-Resende, Júlio César; Antoniazzi, Marcio; de Oliveira Fonseca, Bruno; de Macêdo Matsushita, Graziela; Scapulatempo-Neto, Cristovam; Kerr, Ligia; Castle, Philip E; Schmeler, Kathleen; Richards-Kortum, Rebecca

2018-06-01

Cervical cancer is a leading cause of death in underserved areas of Brazil. This prospective randomized trial involved 200 women in southern/central Brazil with abnormal Papanicolaou tests. Participants were randomized by geographic cluster and referred for diagnostic evaluation either at a mobile van upon its scheduled visit to their local community, or at a central hospital. Participants in both arms underwent colposcopy, in vivo microscopy, and cervical biopsies. We compared rates of diagnostic follow-up completion between study arms, and also evaluated the diagnostic performance of in vivo microscopy compared with colposcopy. There was a 23% absolute and 37% relative increase in diagnostic follow-up completion rates for patients referred to the mobile van (102/117, 87%) compared with the central hospital (53/83, 64%; P = 0.0001; risk ratio = 1.37, 95% CI, 1.14-1.63). In 229 cervical sites in 144 patients, colposcopic examination identified sites diagnosed as cervical intraepithelial neoplasia grade 2 or more severe (CIN2+; 85 sites) with a sensitivity of 94% (95% CI, 87%-98%) and specificity of 50% (95% CI, 42%-58%). In vivo microscopy with real-time automated image analysis identified CIN2+ with a sensitivity of 92% (95% CI, 84%-97%) and specificity of 48% (95% CI, 40%-56%). Women referred to the mobile van were more likely to complete their diagnostic follow-up compared with those referred to a central hospital, without compromise in clinical care. In vivo microscopy in a mobile van provides automated diagnostic imaging with sensitivity and specificity similar to colposcopy. Cancer Prev Res; 11(6); 359-70. ©2018 AACR . ©2018 American Association for Cancer Research.

A new potential spreading factor: Streptomyces koganeiensis hyaluronidase. A comparative study with bovine testes hyaluronidase and recombinant human hyaluronidase of the HA degradation in ECM.

PubMed

Pavan, Mauro; Beninatto, Riccardo; Galesso, Devis; Panfilo, Susi; Vaccaro, Susanna; Messina, Luciano; Guarise, Cristian

2016-04-01

Recombinant human hyaluronidase has been used in the interstitial matrix to promote the dispersion of therapeutics. The production and isolation of an extracellular hyaluronidase from Streptomyces koganeiensis (rHyal_Sk) has recently been described. The specificity of rHyal_Sk has been assessed against heparan sulfate, chondroitin sulfates and sulfated HAs. The oligomers generated by HA degradation have been investigated by MALDI-TOF MS analysis. rHyal_Sk has been compared with BTH and PH20 in vitro, against cross-linked HA (ACP) and HA-aggrecan complex, and in vivo, by means of a diffusion assay in nude mice. Depolymerization of HA by rHyal_Sk gave tetra-, hexa- and octasaccharides in high yields. The reaction mechanism and the high HA specificity were demonstrated. The in vivo diffusion assay, supported by the in vitro tests, evidenced an initially enhanced enzymatic activity of rHyal_Sk compared to BTH and PH20. rHyal_Sk, compared to BTH and PH20, showed higher substrate specificity and no inhibition from GAGs sulfate, together with a superior performance for HA depolymerization in ECM. As better predictive tests for the in vivo activity of hyaluronidase we developed two assays based on the degradation of ACP or of the HA-aggrecan complex. rHyal_Sk is a new potential spreading factor for intradermal drug administration. Hyaluronidases of distinct classes, that show equivalent activities in a common turbidimetric assay, could have different potencies and dose-efficacies in vivo which influences the therapeutic effect. The new proposed in vitro tests are designed to obtain a predictive characterization of the enzyme activity in vivo. Copyright © 2015 Elsevier B.V. All rights reserved.

Optical System Design for Noncontact, Normal Incidence, THz Imaging of in vivo Human Cornea.

PubMed

Sung, Shijun; Dabironezare, Shahab; Llombart, Nuria; Selvin, Skyler; Bajwa, Neha; Chantra, Somporn; Nowroozi, Bryan; Garritano, James; Goell, Jacob; Li, Alex; Deng, Sophie X; Brown, Elliott; Grundfest, Warren S; Taylor, Zachary D

2018-01-01

Reflection mode Terahertz (THz) imaging of corneal tissue water content (CTWC) is a proposed method for early, accurate detection and study of corneal diseases. Despite promising results from ex vivo and in vivo cornea studies, interpretation of the reflectivity data is confounded by the contact between corneal tissue and dielectric windows used to flatten the imaging field. Herein, we present an optical design for non-contact THz imaging of cornea. A beam scanning methodology performs angular, normal incidence sweeps of a focused beam over the corneal surface while keeping the source, detector, and patient stationary. A quasioptical analysis method is developed to analyze the theoretical resolution and imaging field intensity profile. These results are compared to the electric field distribution computed with a physical optics analysis code. Imaging experiments validate the optical theories behind the design and suggest that quasioptical methods are sufficient for designing of THz corneal imaging systems. Successful imaging operations support the feasibility of non-contact in vivo imaging. We believe that this optical system design will enable the first, clinically relevant, in vivo exploration of CTWC using THz technology.

Effects of chlorphentermine and phentermine on the pulmonary disposition of 5-hydroxytryptamine in the rat in vivo

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morita, T.; Mehendale, H.M.

This study was designed to examine whether chlorphentermine (CP) affects pulmonary disposition of 5-hydroxytryptamine (5-HT) in rat in vivo. Further, the effects of CP were compared with those of phentermine (P), the nonchlorinated congener. The right jugular vein and left carotid artery of male Sprague-Dawley rats were cannulated and fresh saline solution containing 150 micrograms indocyanine green and a mixture of labeled and unlabeled 5-HT was injected into the jugular vein, and arterial blood samples were collected for 20 s. In order to compare the effect of CP and P on pulmonary disposition of 5-HT, 2.6 nmol (/sup 14/C)-5-HT wasmore » employed for in vivo single-pass experiments. Each animal was used for 2 in vivo single-pass experiments. After the first experiment, which served as a control, animals received an indicated dose of CP or P, to commence the second ''drug-treated'' in vivo experiment. Pulmonary clearance of 5-HT was inhibited by prior administration of CP (1 mg/kg) by 42%, whereas at the highest dose (20 mg/kg) P inhibited 5-HT clearance by only 25%. Pulmonary accumulation of CP was greater than P at higher doses, and the inhibition of 5-HT clearance correlated with the pulmonary accumulation of these drugs. In addition to the in vivo demonstration of the CP inhibition of pulmonary clearance of 5-HT in the rat, these studies also demonstrate a higher affinity of the lung tissue for CP than for P and a greater propensity for the impairment of pulmonary 5-HT clearance.« less

Progress in Assessing Air Pollutant Risks from In Vitro Exposures: Matching Ozone Dose and Effect in Human Airway Cells

PubMed Central

Hatch, Gary E.; Duncan, Kelly E.; Diaz-Sanchez, David; Schmitt, Michael T.; Ghio, Andrew J.; Carraway, Martha Sue; McKee, John; Dailey, Lisa A.; Berntsen, Jon; Devlin, Robert B.

2014-01-01

In vitro exposures to air pollutants could, in theory, facilitate a rapid and detailed assessment of molecular mechanisms of toxicity. However, it is difficult to ensure that the dose of a gaseous pollutant to cells in tissue culture is similar to that of the same cells during in vivo exposure of a living person. The goal of the present study was to compare the dose and effect of O3 in airway cells of humans exposed in vivo to that of human cells exposed in vitro. Ten subjects breathed labeled O3 (18O3, 0.3 ppm, 2 h) while exercising intermittently. Bronchial brush biopsies and lung lavage fluids were collected 1 h post exposure for in vivo data whereas in vitro data were obtained from primary cultures of human bronchial epithelial cells exposed to 0.25–1.0 ppm 18O3 for 2 h. The O3 dose to the cells was defined as the level of 18O incorporation and the O3 effect as the fold increase in expression of inflammatory marker genes (IL-8 and COX-2). Dose and effect in cells removed from in vivo exposed subjects were lower than in cells exposed to the same 18O3 concentration in vitro suggesting upper airway O3 scrubbing in vivo. Cells collected by lavage as well as previous studies in monkeys show that cells deeper in the lung receive a higher O3 dose than cells in the bronchus. We conclude that the methods used herein show promise for replicating and comparing the in vivo dose and effect of O3 in an in vitro system. PMID:24928893

Vector delivery technique affects gene transfer in the cornea in vivo.

PubMed

Mohan, Rajiv R; Sharma, Ajay; Cebulko, Tyler C; Tandon, Ashish

2010-11-27

This study tested whether controlled drying of the cornea increases vector absorption in mouse and rabbit corneas in vivo and human cornea ex vivo, and studied the effects of corneal drying on gene transfer, structure and inflammatory reaction in the mouse cornea in vivo. Female C57 black mice and New Zealand White rabbits were used for in vivo studies. Donor human corneas were used for ex vivo experiments. A hair dryer was used for drying the corneas after removing corneal epithelium by gentle scraping. The corneas received no, once, twice, thrice, or five times warm air for 10 s with a 5 s interval after each 10 s hair dryer application. Thereafter, balanced salt solution (BSS) was topically applied immediately on the cornea for 2 min using a custom-cloning cylinder. The absorbed BSS was quantified using Hamilton microsyringes. The adeno-associated virus 8 (AAV8) vector (1.1×10(8) genomic copies/µl) expressing marker gene was used to study the effect of corneal drying on gene transfer. Animals were sacrificed on day 14 and gene expression was analyzed using commercial staining kit. Morphological changes and infiltration of inflammatory cells were examined with H & E staining and immunocytochemistry. Mice, rabbit or human corneas subjected to no or 10 s drying showed 6%-8% BSS absorption whereas 20, 30, or 50 s corneal drying showed significantly high 14%-19% (p<0.001), 21%-22% (p<0.001), and 25%-27% (p<0.001) BSS absorption, respectively. The AAV8 application on mouse cornea after 50 s drying showed significantly higher transgene delivery (p<0.05) in vivo with mild-to-moderate changes in corneal morphology. The 30 s of drying also showed significantly (p<0.05) high transgene delivery in mouse stroma in vivo without jeopardizing corneal morphology whereas 10 or 20 s drying showed moderate degree of gene transfer with no altered corneal morphology. Corneas that underwent 50 s drying showed high CD11b-positive cells (p<0.01) compared to control corneas whereas 20 or 30 s air-dried corneas showed insignificant CD11b-positive cells compared to control corneas. Controlled corneal drying with hair dryer increases vector absorption significantly. The dispensing of efficacious AAV serotype into cornea with optimized minimally invasive topical application technique could provide high and targeted expression of therapeutic genes in the stroma in vivo without causing significant side effects.

Aphrodisiac and spermatogenic potential of alkaloidal fraction of Hygrophila spinosa T. Ander in rats.

PubMed

Vyas, Niraj Y; Raval, Manan A

2016-12-24

Seeds of Hygrophila spinosa T. Ander (Acanthaceae) are traditionally used as aphrodisiac and spermatogenic in Indian System of medicine. Preliminary phytochemical screening of plant revealed the presence of alkaloids in seeds. As, alkaloidal fractions of several plants showed aphrodisiac and spermatogenic potential, set of experiments were designed to assess alkaloid enriched fraction of seeds of the plant for spermatogenic and aphrodisiac activity using in vitro and in vivo methods. Alkaloid enriched fraction was prepared and assessed for spermatogenic activity using isolated rat Leydig cells in vitro. The fraction was further evaluated in vivo for spermatogenic and aphrodisiac potential using rat as an experimental animal. Increase in weight of reproductive organs, biochemical evaluation of selected parameters, histological studies of testes and sexual behavioral studies were selected as evaluation parameters for in vivo studies. Isolated rat Leydig cells treated with the fraction showed increased amount of testosterone present in culture media (14.7µg/ml) as compared to that of control (0.8µg/ml). Results of in vivo studies showed increase in serum testosterone level in treated animals (50mg/kg) by (115%), increase in weight of testes (8.0%) as compared to control. Marked improvement in testis histo-architecture of rats evident preliminarily by observing overcrowding of spermatozoa in enlarged lumen of seminiferous tubules in animals treated with testosterone and test fraction. Sertoli cells in treated animals were enlarged with highly granulated cytoplasm. Leydig cells also showed enlarged nucleus and darkly stained cytoplasm as compared to control. Mounting behavior of test animals improved, while latency period was decreased, as observed in behavioral studies. The set studies confirmed the ability of the fraction to stimulate Leydig cells and increased serum testosterone level. Increased testosterone level might be responsible for higher number of spermatozoa in testicular lumen as seen in testicular histology as well as increased libido as observed in behavioral studies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Intraoperative Near-infrared Imaging for Parathyroid Gland Identification by Auto-fluorescence: A Feasibility Study.

PubMed

De Leeuw, Frederic; Breuskin, Ingrid; Abbaci, Muriel; Casiraghi, Odile; Mirghani, Haïtham; Ben Lakhdar, Aïcha; Laplace-Builhé, Corinne; Hartl, Dana

2016-09-01

Parathyroid glands (PGs) can be particularly hard to distinguish from surrounding tissue and thus can be damaged or removed during thyroidectomy. Postoperative hypoparathyroidism is the most common complication after thyroidectomy. Very recently, it has been found that the parathyroid tissue shows near-infrared (NIR) auto-fluorescence which could be used for intraoperative detection, without any use of contrast agents. The work described here presents a histological validation ex vivo of the NIR imaging procedure and evaluates intraoperative PG detection by NIR auto-fluorescence using for the first time to our knowledge a commercially available clinical NIR imaging device. Ex vivo study on resected operative specimens combined with a prospective in vivo study of consecutive patients who underwent total or partial thyroid, or parathyroid surgery at a comprehensive cancer center. During surgery, any tissue suspected to be a potential PG by the surgeon was imaged with the Fluobeam 800 (®) system. NIR imaging was compared to conventional histology (ex vivo) and/or visual identification by the surgeon (in vivo). We have validated NIR auto-fluorescence with an ex vivo study including 28 specimens. Sensitivity and specificity were 94.1 and 80 %, respectively. Intraoperative NIR imaging was performed in 35 patients and 81 parathyroids were identified. In 80/81 cases, the fluorescence signal was subjectively obvious on real-time visualization. We determined that PG fluorescence is 2.93 ± 1.59 times greater than thyroid fluorescence in vivo. Real-time NIR imaging based on parathyroid auto-fluorescence is fast, safe, and non-invasive and shows very encouraging results, for intraoperative parathyroid identification.

Characteristics and Echogenicity of Clinical Ultrasound Contrast Agents: An In Vitro and In Vivo Comparison Study.

PubMed

Hyvelin, Jean-Marc; Gaud, Emmanuel; Costa, Maria; Helbert, Alexandre; Bussat, Philippe; Bettinger, Thierry; Frinking, Peter

2017-05-01

To compare physicochemical characteristics and in vitro and in vivo contrast-enhanced ultrasound imaging performance of 3 commercially available ultrasound contrast agents: SonoVue (Bracco Imaging SpA, Colleretto Giacosa, Italy; also marketed as Lumason in the USA), Definity (Lantheus Medical Imaging, North Billerica, MA) and Optison (GE Healthcare AS, Oslo, Norway). Physicochemical characteristics were measured with a Multisizer Coulter Counter (Beckman Coulter, Fullerton, CA). Two ultrasound systems (Aplio 500; Toshiba Medical Systems Corp, Tochigi-ken, Japan; and Logiq E9; GE Healthcare, Little Chalfont, England) were used with different transducers. Contrast enhancement was measured in vitro by dose-ranging measurements using a custom-built beaker setup; in vivo imaging performances were compared in pigs (heart and liver) and rabbits (liver). Quantitative analyses were performed with VueBox quantification software (Bracco Suisse SA, Plan-les-Ouates, Switzerland). Measured physicochemical characteristics were in agreement with those provided by the manufacturers. In vitro data demonstrated that the performance of SonoVue was similar to or better than that of Definity but superior to Optison (normalized scattered power 2- to 10-fold higher with SonoVue). Similar results were obtained in vivo, although the duration of enhancement in the pig heart was longer for SonoVue compared to Definity, and quantitative analysis revealed higher enhancement for SonoVue (1.5-fold increase). For liver imaging, SonoVue and Definity showed similar contrast enhancement and duration of enhancement, but compared to Optison, both peak enhancement and duration of enhancement were superior for SonoVue (up to 2-fold increase). Imaging performance of SonoVue was similar to or slightly better than that of Definity, but it was superior to Optison for the conditions used in this study. © 2017 by the American Institute of Ultrasound in Medicine.

Neutral red cytotoxicity assays for assessing in vivo carbon nanotube ecotoxicity in mussels--Comparing microscope and microplate methods.

PubMed

Miller, M A; Bankier, C; Al-Shaeri, M A M; Hartl, M G J

2015-12-30

The purpose of the present study was to compare two neutral red retention methods, the more established but very labour-intensive microscope method (NRR) against the more recently developed microplate method (NRU). The intention was to explore whether the sample volume throughput could be increased and potential operator bias avoided. Mussels Mytilus sp. were exposed in vivo to 50, 250 and 500 μg L(-1) single (SWCNTs) or multi-walled carbon nanotubes (MWCNTs). Using the NRR method, SWCNTs and MWCNTs caused concentration dependent decreases in neutral red retention time. However, a concentration dependent decrease in optical density was not observed using the NRU method. We conclude that the NRU method is not sensitive enough to assess carbon nanotube ecotoxicity in vivo in environmentally relevant media, and recommend using the NRR method. Copyright © 2015 Elsevier Ltd. All rights reserved.

Fibrin chain cross-linking, fibrinolysis, and in vivo sealing efficacy of differently structured fibrin sealants.

PubMed

Hedrich, Hans Christian; Simunek, Manuela; Reisinger, Sonja; Ferguson, James; Gulle, Heinz; Goppelt, Andreas; Redl, Heinz

2012-08-01

In this study, we compared the sealing characteristics and efficacy of a fibrin sealant with reduced plasminogen (FS-rplg) and a fibrin sealant with aprotinin as a fibrinolysis inhibitor (FS-apr). The relevant sealing characteristics including clot structure, fibrin chain cross-linking, and clot lysis were tested in the laboratory. The sealing efficacy was then investigated in a follow-up animal model to determine differences in the in vivo sealing properties. A total of 46 animals were available for the final analysis with 23 animals in each treatment arm. In conclusion, we saw differences in vitro between FS-rplg and FS-apr in ultrastructure and α-chain cross-linking rates as well as in the rate of fibrinolysis. These differences may explain the significantly enhanced sealing efficacy in FS-apr compared to FS-rplg shown in vivo in a rabbit intestinal model. Copyright © 2012 Wiley Periodicals, Inc.

Matrix-associated implantation of predifferentiated mesenchymal stem cells versus articular chondrocytes: in vivo results of cartilage repair after 1 year.

PubMed

Marquass, Bastian; Schulz, Ronny; Hepp, Pierre; Zscharnack, Matthias; Aigner, Thomas; Schmidt, Stefanie; Stein, Frank; Richter, Robert; Osterhoff, Georg; Aust, Gabriele; Josten, Christoph; Bader, Augustinus

2011-07-01

The use of predifferentiated mesenchymal stem cells (MSC) leads to better histological results compared with undifferentiated MSC in sheep. This raises the need for a longer term follow-up study and comparison with a clinically established method. We hypothesized that chondrogenic in vitro predifferentiation of autologous MSC embedded in a collagen I hydrogel leads to better structural repair of a chronic osteochondral defect in an ovine stifle joint after 1 year. We further hypothesized that resulting histological results would be comparable with those of chondrocyte-seeded matrix-associated autologous chondrocyte transplantation (MACT). Controlled laboratory study. Predifferentiation period of ovine MSC within collagen gel in vitro was defined by assessment of several cellular and molecular biological parameters. For the animal study, 2 osteochondral lesions (7-mm diameter) were created at the medial femoral condyles of the hind legs in 9 sheep. Implantation of MSC gels was performed 6 weeks after defect creation. Thirty-six defects were divided into 4 treatment groups: (1) chondrogenically predifferentiated MSC gels (pre-MSC gels), (2) undifferentiated MSC gels (un-MSC gels), (3) MACT gels, and (4) untreated controls (UC). Histological, immunohistochemical, and radiological evaluations followed after 12 months. After 12 months in vivo, pre-MSC gels showed significantly better histological outcome compared with un-MSC gels and UC. Compared with MACT gels, the overall scores were higher for O'Driscoll and International Cartilage Repair Society (ICRS). The repair tissue of the pre-MSC group showed immunohistochemical detection of interzonal collagen type II staining. Radiological evaluation supported superior bonding of pre-MSC gels to perilesional native cartilage. Compared with previous work by our group, no degradation of the repair tissue between 6 and 12 months in vivo, particularly in pre-MSC gels, was observed. Repair of chronic osteochondral defects with collagen hydrogels composed of chondrogenically predifferentiated MSC shows no signs of degradation after 1 year in vivo. In addition, pre-MSC gels lead to partially superior histological results compared with articular chondrocytes. The results suggest an encouraging method for future treatment of focal osteochondral defects without donor site morbidity by harvesting articular chondrocytes.

Selective binding of lectins to normal and neoplastic urothelium in rat and mouse bladder carcinogenesis models.

PubMed

Zupančič, Daša; Kreft, Mateja Erdani; Romih, Rok

2014-01-01

Bladder cancer adjuvant intravesical therapy could be optimized by more selective targeting of neoplastic tissue via specific binding of lectins to plasma membrane carbohydrates. Our aim was to establish rat and mouse models of bladder carcinogenesis to investigate in vivo and ex vivo binding of selected lectins to the luminal surface of normal and neoplastic urothelium. Male rats and mice were treated with 0.05 % N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) in drinking water and used for ex vivo and in vivo lectin binding experiments. Urinary bladder samples were also used for paraffin embedding, scanning electron microscopy and immunofluorescence labelling of uroplakins. During carcinogenesis, the structure of the urinary bladder luminal surface changed from microridges to microvilli and ropy ridges and the expression of urothelial-specific glycoproteins uroplakins was decreased. Ex vivo and in vivo lectin binding experiments gave comparable results. Jacalin (lectin from Artocarpus integrifolia) exhibited the highest selectivity for neoplastic compared to normal urothelium of rats and mice. The binding of lectin from Amaranthus caudatus decreased in rat model and increased in mouse carcinogenesis model, indicating interspecies variations of plasma membrane glycosylation. Lectin from Datura stramonium showed higher affinity for neoplastic urothelium compared to the normal in rat and mouse model. The BBN-induced animal models of bladder carcinogenesis offer a promising approach for lectin binding experiments and further lectin-mediated targeted drug delivery research. Moreover, in vivo lectin binding experiments are comparable to ex vivo experiments, which should be considered when planning and optimizing future research.

Biomechanical and histologic evaluation of two application forms of surgical glue for mesh fixation to the abdominal wall.

PubMed

Ortillés, Á; Pascual, G; Peña, E; Rodríguez, M; Pérez-Köhler, B; Mesa-Ciller, C; Calvo, B; Bellón, J M

2017-11-01

The use of an adhesive for mesh fixation in hernia repair reduces chronic pain and minimizes tissue damage in the patient. This study was designed to assess the adhesive properties of a medium-chain (n-butyl) cyanoacrylate glue applied as drops or as a spray in a biomechanical and histologic study. Both forms of glue application were compared to the use of simple-loose or continuous-running polypropylene sutures for mesh fixation. Eighteen adult New Zealand White rabbits were used. For mechanical tests in an ex vivo and in vivo study, patches of polypropylene mesh were fixed to an excised fragment of healthy abdominal tissue or used to repair a partial abdominal wall defect in the rabbit respectively. Depending on the fixation method used, four groups of 12 implants each or 10 implants each respectively for the ex vivo and in vivo studies were established: Glue-Drops, Glue-Spray, Suture-Simple and Suture-Continuous. Biomechanical resistance in the ex vivo implants was tested five minutes after mesh fixation. In vivo implants for biomechanical and histologic assessment were collected at 14 days postimplant. In the ex vivo study, the continuous suture implants showed the highest failure sample tension, while the implants fixed with glue showed lower failure sample tension values. However, the simple and continuous suture implants returned the highest stretch values. In the in vivo implants, failure sample tension values were similar among groups while the implants fixed with a continuous running suture had the higher stretch values, and the glue-fixed implants the lower stretch values. All meshes showed good tissue integration within the host tissue regardless of the fixation method used. Our histologic study revealed the generation of a denser, more mature repair tissue when the cyanoacrylate glue was applied as a spray rather than as drops. Copyright © 2017 Elsevier Ltd. All rights reserved.

Microwave Ablation: Comparison of Simultaneous and Sequential Activation of Multiple Antennas in Liver Model Systems

PubMed Central

Harari, Colin M.; Magagna, Michelle; Bedoya, Mariajose; Lee, Fred T.; Lubner, Meghan G.; Hinshaw, J. Louis; Ziemlewicz, Timothy

2016-01-01

Purpose To compare microwave ablation zones created by using sequential or simultaneous power delivery in ex vivo and in vivo liver tissue. Materials and Methods All procedures were approved by the institutional animal care and use committee. Microwave ablations were performed in both ex vivo and in vivo liver models with a 2.45-GHz system capable of powering up to three antennas simultaneously. Two- and three-antenna arrays were evaluated in each model. Sequential and simultaneous ablations were created by delivering power (50 W ex vivo, 65 W in vivo) for 5 minutes per antenna (10 and 15 minutes total ablation time for sequential ablations, 5 minutes for simultaneous ablations). Thirty-two ablations were performed in ex vivo bovine livers (eight per group) and 28 in the livers of eight swine in vivo (seven per group). Ablation zone size and circularity metrics were determined from ablations excised postmortem. Mixed effects modeling was used to evaluate the influence of power delivery, number of antennas, and tissue type. Results On average, ablations created by using the simultaneous power delivery technique were larger than those with the sequential technique (P < .05). Simultaneous ablations were also more circular than sequential ablations (P = .0001). Larger and more circular ablations were achieved with three antennas compared with two antennas (P < .05). Ablations were generally smaller in vivo compared with ex vivo. Conclusion The use of multiple antennas and simultaneous power delivery creates larger, more confluent ablations with greater temperatures than those created with sequential power delivery. © RSNA, 2015 PMID:26133361

Free radicals induced by sunlight in different spectral regions - in vivo versus ex vivo study.

PubMed

Lohan, Silke B; Müller, Robert; Albrecht, Stephanie; Mink, Kathrin; Tscherch, Kathrin; Ismaeel, Fakher; Lademann, Jürgen; Rohn, Sascha; Meinke, Martina C

2016-05-01

Sunlight represents an exogenous factor stimulating formation of free radicals which can induce cell damage. To assess the effect of the different spectral solar regions on the development of free radicals in skin, in vivo electron paramagnetic resonance (EPR) investigations with human volunteers and ex vivo studies on excised human and porcine skin were carried out. For all skin probes, the ultraviolet (UV) spectral region stimulates the most intensive radical formation, followed by the visible (VIS) and the near infrared (NIR) regions. A comparison between the different skin models shows that for UV light, the fastest and highest production of free radicals could be detected in vivo, followed by excised porcine and human skin. The same distribution pattern was found for the VIS/NIR spectral regions, whereby the differences in radical formation between in vivo and ex vivo were less pronounced. An analysis of lipid composition in vivo before and after exposure to UV light clearly showed modifications in several skin lipid components; a decrease of ceramide subclass [AP2] and an increase of ceramide subclass [NP2], sodium cholesterol sulphate and squalene (SQ) were detectable. In contrast, VIS/NIR irradiation led to an increase of ceramides [AP2] and SCS, and a decrease of SQ. These results, which are largely comparable for the different skin models investigated in vivo and ex vivo, indicate that radiation exposure in different spectral regions strongly influences radical production in skin and also results in changes in skin lipid composition, which is essential for barrier function. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

In vivo near-infrared imaging of fibrin deposition in thromboembolic stroke in mice.

PubMed

Zhang, Yi; Fan, Shufeng; Yao, Yuyu; Ding, Jie; Wang, Yu; Zhao, Zhen; Liao, Lei; Li, Peicheng; Zang, Fengchao; Teng, Gao-Jun

2012-01-01

Thrombus and secondary thrombosis plays a key role in stroke. Recent molecular imaging provides in vivo imaging of activated factor XIII (FXIIIa), an important mediator of thrombosis or fibrinolytic resistance. The present study was to investigate the fibrin deposition in a thromboembolic stroke mice model by FXIIIa-targeted near-infrared fluorescence (NIRF) imaging. The experimental protocol was approved by our institutional animal use committee. Seventy-six C57B/6J mice were subjected to thromboembolic middle cerebral artery occlusion or sham operation. Mice were either intravenously injected with the FXIIIa-targeted probe or control probe. In vivo and ex vivo NIRF imaging were performed thereafter. Probe distribution was assessed with fluorescence microscopy by spectral imaging and quantification system. MR scans were performed to measure lesion volumes in vivo, which were correlated with histology after animal euthanasia. In vivo significant higher fluorescence intensity over the ischemia-affected hemisphere, compared to the contralateral side, was detected in mice that received FXIIIa-targeted probe, but not in the controlled mice. Significantly NIRF signals showed time-dependent processes from 8 to 96 hours after injection of FXIIIa-targeted probes. Ex vivo NIRF image showed an intense fluorescence within the ischemic territory only in mice injected with FXIIIa-targeted probe. The fluorescence microscopy demonstrated distribution of FXIIIa-targeted probe in the ischemic region and nearby micro-vessels, and FXIIIa-targeted probe signals showed good overlap with immune-fluorescent fibrin staining images. There was a significant correlation between total targeted signal from in vivo or ex vivo NIRF images and lesion volume. Non-invasive detection of fibrin deposition in ischemic mouse brain using NIRF imaging is feasible and this technique may provide an in vivo experimental tool in studying the role of fibrin in stroke.

In Vivo Near-Infrared Imaging of Fibrin Deposition in Thromboembolic Stroke in Mice

PubMed Central

Zhang, Yi; Fan, Shufeng; Yao, Yuyu; Ding, Jie; Wang, Yu; Zhao, Zhen; Liao, Lei; Li, Peicheng; Zang, Fengchao; Teng, Gao-Jun

2012-01-01

Objectives Thrombus and secondary thrombosis plays a key role in stroke. Recent molecular imaging provides in vivo imaging of activated factor XIII (FXIIIa), an important mediator of thrombosis or fibrinolytic resistance. The present study was to investigate the fibrin deposition in a thromboembolic stroke mice model by FXIIIa–targeted near-infrared fluorescence (NIRF) imaging. Materials and Methods The experimental protocol was approved by our institutional animal use committee. Seventy-six C57B/6J mice were subjected to thromboembolic middle cerebral artery occlusion or sham operation. Mice were either intravenously injected with the FXIIIa-targeted probe or control probe. In vivo and ex vivo NIRF imaging were performed thereafter. Probe distribution was assessed with fluorescence microscopy by spectral imaging and quantification system. MR scans were performed to measure lesion volumes in vivo, which were correlated with histology after animal euthanasia. Results In vivo significant higher fluorescence intensity over the ischemia-affected hemisphere, compared to the contralateral side, was detected in mice that received FXIIIa-targeted probe, but not in the controlled mice. Significantly NIRF signals showed time-dependent processes from 8 to 96 hours after injection of FXIIIa-targeted probes. Ex vivo NIRF image showed an intense fluorescence within the ischemic territory only in mice injected with FXIIIa-targeted probe. The fluorescence microscopy demonstrated distribution of FXIIIa-targeted probe in the ischemic region and nearby micro-vessels, and FXIIIa-targeted probe signals showed good overlap with immune-fluorescent fibrin staining images. There was a significant correlation between total targeted signal from in vivo or ex vivo NIRF images and lesion volume. Conclusion Non-invasive detection of fibrin deposition in ischemic mouse brain using NIRF imaging is feasible and this technique may provide an in vivo experimental tool in studying the role of fibrin in stroke. PMID:22272319

Antimicrobial Blue Light Therapy for Infectious Keratitis: Ex Vivo and In Vivo Studies.

PubMed

Zhu, Hong; Kochevar, Irene E; Behlau, Irmgard; Zhao, Jie; Wang, Fenghua; Wang, Yucheng; Sun, Xiaodong; Hamblin, Michael R; Dai, Tianhong

2017-01-01

To investigate the effectiveness of antimicrobial blue light (aBL) as an alternative or adjunctive therapeutic for infectious keratitis. We developed an ex vivo rabbit model and an in vivo mouse model of infectious keratitis. A bioluminescent strain of Pseudomonas aeruginosa was used as the causative pathogen, allowing noninvasive monitoring of the extent of infection in real time via bioluminescence imaging. Quantitation of bacterial luminescence was correlated to colony-forming units (CFU). Using the ex vivo and in vivo models, the effectiveness of aBL (415 nm) for the treatment of keratitis was evaluated as a function of radiant exposure when aBL was delivered at 6 or 24 hours after bacterial inoculation. The aBL exposures calculated to reach the retina were compared to the American National Standards Institute standards to estimate aBL retinal safety. Pseudomonas aeruginosa keratitis fully developed in both the ex vivo and in vivo models at 24 hours post inoculation. Bacterial luminescence in the infected corneas correlated linearly to CFU (R2 = 0.921). Bacterial burden in the infected corneas was rapidly and significantly reduced (>2-log10) both ex vivo and in vivo after a single exposure of aBL. Recurrence of infection was observed in the aBL-treated mice at 24 hours after aBL exposure. The aBL toxicity to the retina is largely dependent on the aBL transmission of the cornea. Antimicrobial blue light is a potential alternative or adjunctive therapeutic for infectious keratitis. Further studies of corneal and retinal safety using large animal models, in which the ocular anatomies are similar to that of humans, are warranted.

CAT-8015: A Second-generation Pseudomonas Exotoxin A-Based Immunotherapy Targeting CD22 -Expressing Hematological Malignancies

PubMed Central

Alderson, Ralph F.; Kreitman, Robert J.; Chen, Tianling; Yeung, Peter; Herbst, Ronald; Fox, Judy A.; Pastan, Ira

2009-01-01

Purpose To compare the in vitro and in vivo efficacy of CAT-8015, a second-generation recombinant immunotoxin composed of disulfide linked affinity matured VH and VL chains of the mouse anti-CD22 monoclonal antibody RFB4 fused to PE38, to the parental compound CAT-3888. Experimental Design The biological activity of CAT-8015 was examined in vitro using B cell tumor lines and in vivo in a JD38-based subcutaneous tumor model in NCr athymic mice. Pharmacokinetics and interspecies scaling of CAT-8015 were evaluated in mice, rats, and Cynomologus monkeys. The potential toxicity of CAT-8015 was assessed in monkeys in a toxicological study and compared to CAT-3888. Results The IC50s of CAT-8015 in vitro using the EHEB, MEC1, Daudi, CA46, and JD38 cell lines ranged from 0.3 - 8.6 ng/mL. Pharmacokinetic studies with CAT-8015 were conducted in mouse, rat and Cynomolgus monkey. The T1/2 was calculated to be 0.42, 0.61, and 0.79 hr and the Vss was 1.37, 5.57, and 140.3 mL in mouse, rat, and monkey, respectively. In vivo, when JD38 tumor-bearing animals were treated with CAT-8015 at doses ≥ 75 μg/kg at 48 hr intervals for a total of 3 doses, a rapid reduction in tumor volume and in some cases complete remission in tumor growth was observed. The comparative toxicological study showed comparable clinical and anatomical pathology changes for CAT-8015 and CAT-3888. Conclusions CAT-8015 is a CD22-targeting immunotoxin that, in preclinical studies, has greatly improved efficacy as compared to CAT-3888. PMID:19188153

A comparative evaluation of the chelators H4octapa and CHX-A″-DTPA with the therapeutic radiometal (90)Y.

PubMed

Price, Eric W; Edwards, Kimberly J; Carnazza, Kathryn E; Carlin, Sean D; Zeglis, Brian M; Adam, Michael J; Orvig, Chris; Lewis, Jason S

2016-09-01

To compare the radiolabeling performance, stability, and practical efficacy of the chelators CHX-A″-DTPA and H4octapa with the therapeutic radiometal (90)Y. The bifunctional chelators p-SCN-Bn-H4octapa and p-SCN-Bn-CHX-A″-DTPA were conjugated to the HER2-targeting antibody trastuzumab. The resulting immunoconjugates were radiolabeled with (90)Y to compare radiolabeling efficiency, in vitro and in vivo stability, and in vivo performance in a murine model of ovarian cancer. High radiochemical yields (>95%) were obtained with (90)Y-CHX-A″-DTPA-trastuzumab and (90)Y-octapa-trastuzumab after 15min at room temperature. Both (90)Y-CHX-A″-DTPA-trastuzumab and (90)Y-octapa-trastuzumab exhibited excellent in vitro and in vivo stability. Furthermore, the radioimmunoconjugates displayed high tumoral uptake values (42.3±4.0%ID/g for (90)Y-CHX-A″-DTPA-trastuzumab and 30.1±7.4%ID/g for (90)Y-octapa-trastuzumab at 72h post-injection) in mice bearing HER2-expressing SKOV3 ovarian cancer xenografts. Finally, (90)Y radioimmunotherapy studies performed in tumor-bearing mice demonstrated that (90)Y-CHX-A″-DTPA-trastuzumab and (90)Y-octapa-trastuzumab are equally effective therapeutic agents, as treatment with both radioimmunoconjugates yielded substantially decreased tumor growth compared to controls. Ultimately, this work demonstrates that the acyclic chelators CHX-A″-DTPA and H4octapa have comparable radiolabeling, stability, and in vivo performance, making them both suitable choices for applications requiring (90)Y. Copyright © 2016 Elsevier Inc. All rights reserved.

Behavior of Tip-Steerable Needles in ex vivo and in vivo Tissue

PubMed Central

Majewicz, Ann; Marra, Steven P.; van Vledder, Mark G.; Lin, MingDe; Choti, Michael A.; Song, Danny Y.; Okamura, Allison M.

2012-01-01

Robotic needle steering is a promising technique to improve the effectiveness of needle-based clinical procedures, such as biopsies and ablation, by computer-controlled, curved insertions of needles within solid organs. In this paper, we explore the capabilities, challenges, and clinical relevance of asymmetric-tip needle steering though experiments in ex vivo and in vivo tissue. We evaluate the repeatability of needle insertion in inhomogeneous biological tissue and compare ex vivo and in vivo needle curvature and insertion forces. Steerable needles curved more in kidney than in liver and prostate, likely due to differences in tissue properties. Pre-bent needles produced higher insertion forces in liver and more curvature in vivo than ex vivo. When compared to straight stainless steel needles, steerable needles did not cause a measurable increase in tissue damage and did not exert more force during insertion. The minimum radius of curvature achieved by pre-bent needles was 5.23 cm in ex vivo tissue, and 10.4 cm in in vivo tissue. The curvatures achieved by bevel tip needles were negligible for in vivo tissue. The minimum radius of curvature for bevel tip needles in ex vivo tissue was 16.4 cm; however, about half of the bevel tip needles had negligible curvatures. We also demonstrate a potential clinical application of needle steering by targeting and ablating overlapping regions of cadaveric canine liver. PMID:22711767

Evaluation of hybrid algorithm for analysis of scattered light using ex vivo nuclear morphology measurements of cervical epithelium

PubMed Central

Ho, Derek; Drake, Tyler K.; Bentley, Rex C.; Valea, Fidel A.; Wax, Adam

2015-01-01

We evaluate a new hybrid algorithm for determining nuclear morphology using angle-resolved low coherence interferometry (a/LCI) measurements in ex vivo cervical tissue. The algorithm combines Mie theory based and continuous wavelet transform inverse light scattering analysis. The hybrid algorithm was validated and compared to traditional Mie theory based analysis using an ex vivo tissue data set. The hybrid algorithm achieved 100% agreement with pathology in distinguishing dysplastic and non-dysplastic biopsy sites in the pilot study. Significantly, the new algorithm performed over four times faster than traditional Mie theory based analysis. PMID:26309741

In vivo gastric residence and gastroprotective effect of floating gastroretentive tablet of DA-9601, an extract of Artemisia asiatica, in beagle dogs

PubMed Central

Kim, Jeong Soo; Cha, Kwang Ho; Kang, Seung Yeob; Won, Donghan; Jang, Sun Woo; Son, Miwon; Son, Moon Ho; Choi, Ho Jung; Lee, Young Won; Kang, Myung Joo

2016-01-01

Objective DA-9601, an extract of Artemisia asiatica containing eupatilin and jaceosidin as active compounds, has been prescribed to treat gastritis in Asia. In recent times, sustained-release, floating gastroretentive (GR) tablets of DA-9601 are available on the market. In the present study, the physical properties and in vitro drug release profile, in vivo gastric residence time, and gastroprotective effect of GR tablet were compared to those of immediate release (IR) tablets of DA-9601. Method In vitro buoyancy behavior (floating lag time and duration) and release profile of eupatilin were assessed in acidic medium. The in vivo intragastric behaviors of the barium sulfate-loaded IR and GR tablets were evaluated in beagle dogs by radiographic studies. Local gastroprotective effect was compared in an experimentally induced gastric lesion in beagle dogs after oral administration of IR (three times per day) or GR (twice daily) tablets for 15 days. Results Upon contact with gastric juice, a low-density floating tablet (apparent density of 0.93 g/cm3) was buoyant on the medium and was upheld for 14 hours, providing sustained drug release profile, whereas the IR tablet disintegrated within 10 minutes, showing complete drug release within 2 hours. In vivo radiographic studies showed that the GR tablet was retained for >4 hours in the stomach. Both DA-9601 formulations remarkably alleviated gastric mucosal injury compared to placebo group, when observed by gastric endoscopy. Conclusion Twice-daily GR tablets exhibited a prolonged gastric residence time and a remarkable mucosal restoration effect in animal models. Therefore, the GR system of DA-9601 could be a substitute dosage form for the treatment of gastritis, while reducing the dosing frequency and thus improving patient compliance. PMID:27354765

In vivo gastric residence and gastroprotective effect of floating gastroretentive tablet of DA-9601, an extract of Artemisia asiatica, in beagle dogs.

PubMed

Kim, Jeong Soo; Cha, Kwang Ho; Kang, Seung Yeob; Won, Donghan; Jang, Sun Woo; Son, Miwon; Son, Moon Ho; Choi, Ho Jung; Lee, Young Won; Kang, Myung Joo

2016-01-01

DA-9601, an extract of Artemisia asiatica containing eupatilin and jaceosidin as active compounds, has been prescribed to treat gastritis in Asia. In recent times, sustained-release, floating gastroretentive (GR) tablets of DA-9601 are available on the market. In the present study, the physical properties and in vitro drug release profile, in vivo gastric residence time, and gastroprotective effect of GR tablet were compared to those of immediate release (IR) tablets of DA-9601. In vitro buoyancy behavior (floating lag time and duration) and release profile of eupatilin were assessed in acidic medium. The in vivo intragastric behaviors of the barium sulfate-loaded IR and GR tablets were evaluated in beagle dogs by radiographic studies. Local gastroprotective effect was compared in an experimentally induced gastric lesion in beagle dogs after oral administration of IR (three times per day) or GR (twice daily) tablets for 15 days. Upon contact with gastric juice, a low-density floating tablet (apparent density of 0.93 g/cm(3)) was buoyant on the medium and was upheld for 14 hours, providing sustained drug release profile, whereas the IR tablet disintegrated within 10 minutes, showing complete drug release within 2 hours. In vivo radiographic studies showed that the GR tablet was retained for >4 hours in the stomach. Both DA-9601 formulations remarkably alleviated gastric mucosal injury compared to placebo group, when observed by gastric endoscopy. Twice-daily GR tablets exhibited a prolonged gastric residence time and a remarkable mucosal restoration effect in animal models. Therefore, the GR system of DA-9601 could be a substitute dosage form for the treatment of gastritis, while reducing the dosing frequency and thus improving patient compliance.

Measurement of the refractive index of soft contact lenses during wear.

PubMed

Varikooty, Jalaiah; Keir, Nancy; Woods, Craig A; Fonn, Desmond

2010-01-01

To determine whether the refractive index (RI) of a soft contact lens can be evaluated using refractometry while the lens remains on the eye and to compare this with more traditional ex vivo RI measurements. A slitlamp apparatus was modified to incorporate a customized Atago hand refractometer. With a double-masked study design, nine adapted symptomatic soft contact lens wearers wore a contact lens in each eye (lotrafilcon B and etafilcon A) in a randomized order. In vivo RI was determined from the relative Brix scale measurements immediately after lens insertion and after 1 and 10 hr of lens wear. Ex vivo refractometry was performed after 10 hr of lens wear for comparison. Means +/- standard errors of the means are reported. In vivo RI values at baseline were 1.422 +/- 0.0004 (lotrafilcon B) and 1.405 +/- 0.0021 (etafilcon A); after 1 hr of lens wear, values were 1.423 +/- 0.0006 and 1.408 +/- 0.0007, respectively; and after 10 hr of lens wear, values were 1.424 +/- 0.0004 and 1.411 +/- 0.0010, respectively. Ex vivo RI values at the end of the 10 hr wearing period were 1.424 +/- 0.0003 (lotrafilcon B) and 1.412 +/- 0.0017 (etafilcon A). The change in in vivo RI across the day was statistically significant for the etafilcon A lens (repeated-measures analysis of variance, P<0.01) but not for the lotrafilcon B lens (P>0.05). This novel adaptation of refractometry was able to measure the RI of soft contact lenses during wear (without lens removal). End of day RI measurements using in vivo and ex vivo refractometry were comparable with each other. Future work is required to determine whether this in vivo method can improve our understanding of the relationships between soft contact lens RI, hydration, on-eye lens performance, and symptomology.

Formulation and in vitro and in vivo characterization of a phenytoin self-emulsifying drug delivery system (SEDDS).

PubMed

Atef, Eman; Belmonte, Albert A

2008-11-15

The aim of this study is to develop and characterize a self-emulsifying drug delivery system (SEDDS) of phenytoin, and to compare its relative bioavailability to a commercially available suspension. Four phenytoin SEDDS were prepared and evaluated. Following emulsification, the optimized formula was selected to have the smallest mean particle size and the highest absolute zeta potential, which should yield the formation of a stable emulsion. Its dissolution characteristics were superior to the other SEDDS formulas. In vivo and in vitro tests were run to compare the optimized formula, SEDDS II, to a commercially available Dilantin suspension. The in vitro dissolution indicated a significant improvement in phenytoin release characteristics. The in vivo study using male rats showed a clear enhancement in phenytoin oral absorption from SEDDS compared to Dilantin suspension. The area under the curve AUC((-10min-->10h)) of phenytoin after SEDDS administration increased by 2.3 times compared to Dilantin (p<0.05), and the rate of absorption of phenytoin was significantly faster from the SEDDS. The concentration after 30min (C(30min)) of SEDDS administration was 4.9 times higher than C(30min) after Dilantin administration (p<0.05). A sustained effect of phenytoin in plasma was also observed. After 12 weeks storage, SEDDS II was found to be chemically and physically stable under stressed conditions.

Antibacterial, anti-inflammatory, and bone-regenerative dual-drug-loaded calcium phosphate nanocarriers-in vitro and in vivo studies.

PubMed

Madhumathi, K; Rubaiya, Y; Doble, Mukesh; Venkateswari, R; Sampath Kumar, T S

2018-05-01

A dual local drug delivery system (DDS) composed of calcium phosphate bioceramic nanocarriers aimed at treating the antibacterial, anti-inflammatory, and bone-regenerative aspects of periodontitis has been developed. Calcium-deficient hydroxyapatite (CDHA, Ca/P = 1.61) and tricalcium phosphate (β-TCP) were prepared by microwave-accelerated wet chemical synthesis method. The phase purity of the nanocarriers was confirmed by x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR), while the transmission electron microscopy (TEM) confirmed their nanosized morphology. CDHA was selected as carrier for the antibiotic (tetracycline) while TCP was chosen as the anti-inflammatory drug (ibuprofen) carrier. Combined drug release profile was studied in vitro from CDHA/TCP (CTP) system and compared with a HA/TCP (BCP) biphasic system. The tetracycline and ibuprofen release rate was 71 and 23% from CTP system as compared to 63 and 20% from BCP system. CTP system also showed a more controlled drug release profile compared to BCP system. Modeling of drug release kinetics from CTP system indicated that the release follows Higuchi model with a non-typical Fickian diffusion profile. In vitro biological studies showed the CTP system to be biocompatible with significant antibacterial and anti-inflammatory activity. In vivo implantation studies on rat cranial defects showed greater bone healing and new bone formation in the drug-loaded CTP system compared to control (no carrier) at the end of 12 weeks. The in vitro and in vivo results suggest that the combined drug delivery platform can provide a comprehensive management for all bone infections requiring multi-drug therapy.

In vivo detection of free radicals in mouse septic encephalopathy using molecular MRI and immuno-spin trapping.

PubMed

Towner, Rheal A; Garteiser, Philippe; Bozza, Fernando; Smith, Nataliya; Saunders, Debra; d' Avila, Joana C P; Magno, Flora; Oliveira, Marcus F; Ehrenshaft, Marilyn; Lupu, Florea; Silasi-Mansat, Robert; Ramirez, Dario C; Gomez-Mejiba, Sandra E; Mason, Ronald P; Castro Faria-Neto, Hugo C

2013-12-01

Free radicals are known to play a major role in sepsis. Combined immuno-spin trapping and molecular magnetic resonance imaging (MRI) was used to detect in vivo and in situ levels of free radicals in murine septic encephalopathy after cecal ligation and puncture (CLP). DMPO (5,5-dimethyl pyrroline N-oxide) was injected over 6h after CLP, before administration of an anti-DMPO probe (anti-DMPO antibody bound to albumin-gadolinium-diethylene triamine pentaacetic acid-biotin MRI targeting contrast agent). In vitro assessment of the anti-DMPO probe in oxidatively stressed mouse astrocytes significantly decreased T1 relaxation (p < 0.0001) compared to controls. MRI detected the presence of anti-DMPO adducts via a substantial decrease in %T1 change within the hippocampus, striatum, occipital, and medial cortex brain regions (p < 0.01 for all) in septic animals compared to shams, which was sustained for over 60 min (p < 0.05 for all). Fluorescently labeled streptavidin was used to target the anti-DMPO probe biotin, which was elevated in septic brain, liver, and lungs compared to sham. Ex vivo DMPO adducts (qualitative) and oxidative products, including 4-hydroxynonenal and 3-nitrotyrosine (quantitative, p < 0.05 for both), were elevated in septic brains compared to shams. This is the first study that has reported on the detection of in vivo and in situ levels of free radicals in murine septic encephalopathy. Copyright © 2013 Elsevier Inc. All rights reserved.

Prospective, randomized comparison of 3 different hemoclips for the treatment of acute upper GI hemorrhage in an established experimental setting.

PubMed

Kato, Masayuki; Jung, Yunho; Gromski, Mark A; Chuttani, Ram; Matthes, Kai

2012-01-01

Recently, endoscopic clip application devices have undergone redesign and improvements to optimize their clinical use and effectiveness. Initially designed for the treatment of bleeding nonvariceal lesions, these devices are also increasingly used for the closure of perforations, fistulas, and anastomotic leaks. Several clinical studies, both randomized and nonrandomized, have used endoscopic hemoclips for hemostasis. However, no comparative studies have yet been reported in the literature comparing the latest endoscopic clip devices for usability and effectiveness for hemostasis of acute upper GI hemorrhage. We aimed to compare the usability and efficacy of 3 different types of endoscopic clip application devices in an established experimental setting by using a porcine ex-vivo simulator of upper GI hemorrhage. Randomized, controlled, ex-vivo study. Academic medical center. Spurting vessels were created within ex-vivo porcine stomachs as published in prior studies. The vessels were attached to a pressure transducer to record the pressure of the circulating blood replacement. Before the initiation of bleeding, each vessel was randomized to 1 of 3 endoscopic clipping devices: 2 different commonly used hemoclips deployed through the working channel and 1 novel clip deployed via an over-the-scope applications device. Two investigators treated 45 bleeding sites (15 bleeding sites for each device at various randomized locations in the stomach: fundus, body, and antrum). Usability was measured via the endpoints of procedure time and quantity of clips required to achieve hemostasis. Efficacy was measured via the endpoint of pressure increase (Δp) from baseline to after treatment. All of the 45 hemostasis treatments were carried out successfully. The mean procedure times were significantly different among the hemoclips, with the clip deployed in an over-the-scope fashion requiring significantly less time to attain hemostasis compared with the other 2 clips. For number of clips needed to attain hemostasis, the clip deployed in an over-the-scope fashion was significantly superior to the others. There were also significant differences among the changes in pressure (Δp ± SD) among the different hemoclips tested. Ex-vivo study. In this prospective, randomized ex-vivo study, we observed significant differences in the usability (time to achieve hemostasis and number of clips required) and the efficacy (change in pressure achieved by the hemoclips) among the 3 clips. The clip applied in the over-the-scope fashion was superior to the other 2 tested clips with regard to time to achieve hemostasis and number of clips required. Copyright © 2012 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

Comparison of 68Ga- and fluorescence-labeled microspheres for measurement of relative pulmonary perfusion in anesthetized pigs.

PubMed

Braune, Anja; Scharffenberg, Martin; Naumann, Anne; Bluth, Thomas; de Abreu, Marcelo Gama; Kotzerke, Jörg

2018-06-01

We compared 68 Gallium ( 68 Ga)- and fluorescence-labeled microspheres for measurement of pulmonary perfusion distribution in anesthetized pigs without lung injury. In two mechanically ventilated pigs, the distribution of pulmonary perfusion was marked in vivo with 68 Ga- and fluorescence-labeled microspheres in supine and prone position. After each injection, the distribution of 68 Ga-labeled microspheres was measured in vivo with positron emission tomography/ computed tomography (PET/CT) in the position in which microspheres were injected and vice versa. The distribution of fluorescence-labeled microspheres was measured ex vivo . Perfusion distributions were compared between methods and postures within four lung regions and along the ventro-dorsal gradient. After each injection of 68 Ga-labeled microspheres, changes in ventro-dorsal perfusion gradients induced by repositioning were compared for volume- and mass-normalized PET/CT measurements. Regional and gradient analyses of in vivo and ex vivo measurements, respectively, consistently revealed higher pulmonary perfusion in dorsal than ventral regions in supine positioned animals. Both methods showed more pronounced perfusion gradients in supine compared to prone position. Changes in animal position were associated with alterations in the ventro-dorsal perfusion gradient when volume-, but not mass-normalization was conducted for PET/CT data. Ex vivo fluorescence- and in vivo 68 Ga-labeled microspheres measurements revealed similar perfusion distributions. Mass-normalized perfusion measurements by 68 Ga-labeled microspheres and PET/CT were not affected by positioning artifacts. Schattauer GmbH.

Patient-specific musculoskeletal modeling of the hip joint for preoperative planning of total hip arthroplasty: A validation study based on in vivo measurements

PubMed Central

Schick, Fabian; Asseln, Malte; Damm, Philipp; Radermacher, Klaus

2018-01-01

Validation of musculoskeletal models for application in preoperative planning is still a challenging task. Ideally, the simulation results of a patient-specific musculoskeletal model are compared to corresponding in vivo measurements. Currently, the only possibility to measure in vivo joint forces is to implant an instrumented prosthesis in patients undergoing a total joint replacement. In this study, a musculoskeletal model of the AnyBody Modeling System was adapted patient-specifically and validated against the in vivo hip joint force measurements of ten subjects performing one-leg stance and level walking. The impact of four model parameters was evaluated; hip joint width, muscle strength, muscle recruitment, and type of muscle model. The smallest difference between simulated and in vivo hip joint force was achieved by using the hip joint width measured in computed tomography images, a muscle strength of 90 N/cm2, a third order polynomial muscle recruitment, and a simple muscle model. This parameter combination reached mean deviations between simulation and in vivo measurement during the peak force phase of 12% ± 14% in magnitude and 11° ± 5° in orientation for one-leg stance and 8% ± 6% in magnitude and 10° ± 5° in orientation for level walking. PMID:29649235

Chemical mapping of anxiety in the brain of healthy humans: an in vivo 1H-MRS study on the effects of sex, age, and brain region.

PubMed

Grachev, I D; Apkarian, A V

2000-12-01

We recently presented results in an in vivo study of human brain chemistry in 'physiologic' anxiety, i.e., the anxiety of normal everyday life. Normal subjects with high anxiety demonstrated increased concentration of chemicals in orbital frontal cortex (OFC) as compared to lower anxiety. In a separate study of aging we demonstrated a decrease of total chemical concentration in OFC of middle-aged subjects, as compared with younger age. This brain region also showed gender dependence; men demonstrating decreased chemical concentration compared to women. We hypothesized that these sex- and age-dependent differences in OFC chemistry changes are a result of anxiety effects on this brain region. In the present study we examined these sex- and age-differential regional brain chemistry changes (as identified by localized in vivo proton magnetic resonance spectroscopy [1H-MRS]) in relation to the state-trait-anxiety (as measured by the State-Trait Anxiety Inventory) in 35 healthy subjects. The concentrations for all nine chemicals of 1H-MRS spectra were measured relative to creatine across multiple brain regions, including OFC in the left hemisphere. Analysis of variance showed anxiety-specific effects on chemical concentration changes in OFC, which were different for both sexes and age groups. Male subjects showed larger effect of anxiety on OFC chemistry as compared to females when the same sex high-anxiety subjects were compared to lower anxiety. Similarly, middle-aged subjects showed larger effect of anxiety on OFC chemistry as compared to younger age when the same age subjects with high anxiety were compared to lower anxiety. Largest effect of anxiety on OFC chemistry was due to changes of N-Acetyl aspartate. The results indicate that the state-trait anxiety has sex- and age-differential patterns on OFC chemistry in healthy humans, providing new information about the neurobiological roots of anxiety.

In Vivo and In Vitro Nitinol Corrosion Properties

NASA Astrophysics Data System (ADS)

Lonn, Melissa K.; Metcalf, Justin M.; Choules, Brian D.

2015-09-01

Regulatory authorities often require in vitro testing on medical devices prior to approval. Current standardized corrosion testing methods (ASTM F2129) require testing in a non-physiologic, de-oxygenated solution for a pre-exposure time of ≤1 h; however, no correlations between the prescribed simulated environment and whole blood conditions have been elucidated. This study compared open circuit potential (OCP), breakdown potentials (Eb), Eb - OCP, and cyclic polarization curves tested in vivo (OCP only) and in vitro in whole blood to those tested in phosphate-buffered saline (PBS). Two oxide thicknesses of Nitinol, two solution oxygen contents (deaerated and aerated solutions), and two pre-exposure durations (acute and chronic) were investigated. The in vitro OCP in whole blood was not significantly different than the in vivo OCP, suggesting that whole blood in vitro can be used to determine baseline corrosion behavior of medical implants. Eb - OCP tested per ASTM F2129 was comparable to acute whole blood and was conservative compared to chronic whole blood for both oxide thicknesses. However, OCP, Eb, and cyclic polarization curves were not always comparable to whole blood. Testing in aerated PBS achieved Eb, Eb - OCP, and cyclic polarization curves that were comparable to or more conservative than whole blood testing, regardless of pre-exposure duration and oxide thickness.

Lyophilized plasma attenuates vascular permeability, inflammation and lung injury in hemorrhagic shock.

PubMed

Pati, Shibani; Peng, Zhanglong; Wataha, Katherine; Miyazawa, Byron; Potter, Daniel R; Kozar, Rosemary A

2018-01-01

In severe trauma and hemorrhage the early and empiric use of fresh frozen plasma (FFP) is associated with decreased morbidity and mortality. However, utilization of FFP comes with the significant burden of shipping and storage of frozen blood products. Dried or lyophilized plasma (LP) can be stored at room temperature, transported easily, reconstituted rapidly with ready availability in remote and austere environments. We have previously demonstrated that FFP mitigates the endothelial injury that ensues after hemorrhagic shock (HS). In the current study, we sought to determine whether LP has similar properties to FFP in its ability to modulate endothelial dysfunction in vitro and in vivo. Single donor LP was compared to single donor FFP using the following measures of endothelial cell (EC) function in vitro: permeability and transendothelial monolayer resistance; adherens junction preservation; and leukocyte-EC adhesion. In vivo, using a model of murine HS, LP and FFP were compared in measures of HS- induced pulmonary vascular inflammation and edema. Both in vitro and in vivo in all measures of EC function, LP demonstrated similar effects to FFP. Both FFP and LP similarly reduced EC permeability, increased transendothelial resistance, decreased leukocyte-EC binding and persevered adherens junctions. In vivo, LP and FFP both comparably reduced pulmonary injury, inflammation and vascular leak. Both FFP and LP have similar potent protective effects on the vascular endothelium in vitro and in lung function in vivo following hemorrhagic shock. These data support the further development of LP as an effective plasma product for human use after trauma and hemorrhagic shock.

The relationship between religion and thought-action fusion: use of an in vivo paradigm.

PubMed

Berman, Noah C; Abramowitz, Jonathan S; Pardue, Caleb M; Wheaton, Michael G

2010-07-01

Research has demonstrated that higher levels of religiosity are positively correlated with thought-action fusion (TAF), a set of cognitive biases found to be associated with obsessive-compulsive symptoms. However, previous studies have exclusively relied on a nomothetic approach to measuring TAF using a single self-report instrument, the thought-action fusion scale. The current study examined the relationship between religiosity and TAF using an in vivo behaviorally-based assessment in which participants thought about and wrote down thoughts of negative events involving loved ones. Forty-three highly religious Protestant Christians were compared to 30 Atheists/Agnostics on their in vivo ratings of anxiety, estimates of likelihood, and moral wrongness related to the negative thoughts. Results indicated that compared to the non-religious participants, those who were highly religious believed that writing and thinking about the negative events was more morally wrong and increased the likelihood of the event. Results are discussed in terms of the potential relationship between certain religious teachings and TAF-related beliefs about the importance, significance, and influence of thoughts. Copyright 2010 Elsevier Ltd. All rights reserved.

Formulation and in Vitro, ex Vivo and in Vivo Evaluation of Elastic Liposomes for Transdermal Delivery of Ketorolac Tromethamine.

PubMed

Nava, Guadalupe; Piñón, Elizabeth; Mendoza, Luis; Mendoza, Néstor; Quintanar, David; Ganem, Adriana

2011-12-15

The objective of the current study was to formulate ketorolac tromethamine-loaded elastic liposomes and evaluate their in vitro drug release and their ex vivo and in vivo transdermal delivery. Ketorolac tromethamine (KT), which is a potent analgesic, was formulated in elastic liposomes using Tween 80 as an edge activator. The elastic vesicles were prepared by film hydration after optimizing the sonication time and number of extrusions. The vesicles exhibited an entrapment efficiency of 73 ± 11%, vesicle size of 127.8 ± 3.4 nm and a zeta potential of -12 mV. In vitro drug release was analyzed from liposomes and an aqueous solution, using Franz diffusion cells and a cellophane dialysis membrane with molecular weight cut-off of 8000 Da. Ex vivo permeation of KT across pig ear skin was studied using a Franz diffusion cell, with phosphate buffer (pH 7.4) at 32 °C as receptor solution. An in vivo drug permeation study was conducted on healthy human volunteers using a tape-stripping technique. The in vitro results showed (i) a delayed release when KT was included in elastic liposomes, compared to an aqueous solution of the drug; (ii) a flux of 0.278 mg/cm2h and a lag time of about 10 h for ex vivo permeation studies, which may indicate that KT remains in the skin (with the possibility of exerting a local effect) before reaching the receptor medium; (iii) a good correlation between the total amount permeated, the penetration distance (both determined by tape stripping) and transepidermal water loss (TEWL) measured during the in vivo permeation studies. Elastic liposomes have the potential to transport the drug through the skin, keep their size and drug charge, and release the drug into deep skin layers. Therefore, elastic liposomes hold promise for the effective topical delivery of KT.

Development of an Extended-Release Formulation for Apremilast and a Level A in Vitro-in Vivo Correlation Study in Beagle Dogs.

PubMed

Tang, Meiqiong; Hu, Ping; Huang, Shigui; Zheng, Qiang; Yu, Hao; He, Yun

2016-11-01

The primary objective of the present study was to develop extended-release matrix formulations of apremilast for the oral delivery and to study their in vitro and in vivo correlation. Five extended-release formulations containing hydroxypropylmethylcellulose (HPMC) as the retarding excipient with different release rate of apremilast were prepared. Dissolution tests of all the formulated tablets were performed in water, pH 4.0 and 6.8 buffer solutions. The in vitro release kinetics was studied and supported by Korsmeyer-Peppas's equation as it presented highest values of correlation coefficients (r 2 up to 0.966). Among all formulated tablets, F2 (HPMC 25%) and F4 (HPMC 35%) were selected to perform an in vivo study in beagle dogs to obtain various pharmacokinetic parameters, i.e., peak plasma concentration (C max ), time to peak plasma concentration (t max ), area under the plasma-concentration vs. time curve (AUC). Higher t max and t 1/2 , lower C max and elimination coefficient (K e ) were observed for both extended formulations compared to marketed immediate-release products (Otezla ® ). Level A in vitro-in vivo correlations were created with the help of Wagner-Nelson and numeric deconvolution methods. Both formulations showed good in vitro-in vivo correlations whose accuracies were further verified by an internal validation.

Linear and Nonlinear Viscoelastic Modeling of Aorta and Carotid Pressure-Area Dynamics under in vivo and ex vivo Conditions

PubMed Central

Valdez-Jasso, Daniela; Bia, Daniel; Zócalo, Yanina; Armentano, Ricardo L.; Haider, Mansoor A.; Olufsen, Mette S.

2013-01-01

A better understanding of the biomechanical properties of the arterial wall provides important insight into arterial vascular biology under normal (healthy) and pathological conditions. This insight has potential to improve tracking of disease progression and to aid in vascular graft design and implementation. In this study, we use linear and nonlinear viscoelastic models to predict biomechanical properties of the thoracic descending aorta and the carotid artery under ex vivo and in vivo conditions in ovine and human arteries. Models analyzed include a four-parameter (linear) Kelvin viscoelastic model and two five-parameter nonlinear viscoelastic models (an arctangent and a sigmoid model) that relate changes in arterial blood pressure to the vessel cross-sectional area (via estimation of vessel strain). These models were developed using the framework of Quasilinear Viscoelasticity (QLV) theory and were validated using measurements from the thoracic descending aorta and the carotid artery obtained from human and ovine arteries. In vivo measurements were obtained from ten ovine aortas and ten human carotid arteries. Ex vivo measurements (from both locations) were made in eleven male Merino sheep. Biomechanical properties were obtained through constrained estimation of model parameters. To further investigate the parameter estimates we computed standard errors and confidence intervals and we used analysis of variance to compare results within and between groups. Overall, our results indicate that optimal model selection depends on the arterial type. Results showed that for the thoracic descending aorta (under both experimental conditions) the best predictions were obtained with the nonlinear sigmoid model, while under healthy physiological pressure loading the carotid arteries nonlinear stiffening with increasing pressure is negligible, and consequently, the linear (Kelvin) viscoelastic model better describes the pressure-area dynamics in this vessel. Results comparing biomechanical properties show that the Kelvin and sigmoid models were able to predict the zero-pressure vessel radius; that under ex vivo conditions vessels are more rigid, and comparatively, that the carotid artery is stiffer than the thoracic descending aorta; and that the viscoelastic gain and relaxation parameters do not differ significantly between vessels or experimental conditions. In conclusion, our study demonstrates that the proposed models can predict pressure-area dynamics and that model parameters can be extracted for further interpretation of biomechanical properties. PMID:21203846

Non Invasive High Resolution In Vivo Imaging of α-napthylisothiocyanate (ANIT) Induced Hepatobiliary Toxicity in STII Medaka

PubMed Central

Hardman, Ron; Kullman, Seth; Yuen, Bonny; Hinton, David E.

2009-01-01

A novel transparent stock of medaka (Oryzias latipes; STII), homozygous recessive for all four pigments (iridophores, xanthophores, leucophores, melanophores), permits transcutaneous, high resolution ( < 1μm) imaging of internal organs and tissues in living individuals. We applied this model to in vivo investigation of α-napthylisothiocyanate (ANIT) induced hepatobiliary toxicity. Distinct phenotypic responses to ANIT involving all aspects of intrahepatic biliary passageways (IHBPs), particularly bile preductular epithelial cells (BPDECs), associated with transitional passageways between canaliculi and bile ductules, were observed. Alterations included: attenuation/dilation of bile canaliculi, bile preductular lesions, hydropic vacuolation of hepatocytes and BPDECs, mild BPDEC hypertrophy, and biliary epithelial cell (BEC) hyperplasia. Ex vivo histological, immunohistochemical, and ultrastructural studies were employed to aid in interpretation of, and verify, in vivo findings. 3D reconstructions from in vivo investigations provided quantitative morphometric and volumetric evaluation of ANIT exposed and untreated livers. The findings presented show for the first time in vivo evaluation of toxicity in the STII medaka hepatobiliary system, and, in conjunction with prior in vivo work characterizing normalcy, advance our comparative understanding of this lower vertebrate hepatobiliary system and its response to toxic insult. PMID:18022256

Toxicity of copper oxide nanoparticles in lung epithelial cells exposed at the air-liquid interface compared with in vivo assessment.

PubMed

Jing, Xuefang; Park, Jae Hong; Peters, Thomas M; Thorne, Peter S

2015-04-01

The toxicity of spark-generated copper oxide nanoparticles (CuONPs) was evaluated in human bronchial epithelial cells (HBEC) and lung adenocarcinoma cells (A549 cells) using an in vitro air-liquid interface (ALI) exposure system. Dose-response results were compared to in vivo inhalation and instillation studies of CuONPs. Cells were exposed to filtered, particle-free clean air (controls) or spark-generated CuONPs. The number median diameter, geometric standard deviation and total number concentration of CuONPs were 9.2 nm, 1.48 and 2.27×10(7)particles/cm(3), respectively. Outcome measures included cell viability, cytotoxicity, oxidative stress and proinflammatory chemokine production. Exposure to clean air (2 or 4h) did not induce toxicity in HBEC or A549 cells. Compared with controls, CuONP exposures significantly reduced cell viability, increased lactate dehydrogenase (LDH) release and elevated levels of reactive oxygen species (ROS) and IL-8 in a dose-dependent manner. A549 cells were significantly more susceptible to CuONP effects than HBEC. Antioxidant treatment reduced CuONP-induced cytotoxicity. When dose was expressed per area of exposed epithelium there was good agreement of toxicity measures with murine in vivo studies. This demonstrates that in vitro ALI studies can provide meaningful data on nanotoxicity of metal oxides. Copyright © 2015 Elsevier Ltd. All rights reserved.

Corneal wound healing promoted by 3 blood derivatives: an in vitro and in vivo comparative study.

PubMed

Freire, Vanesa; Andollo, Noelia; Etxebarria, Jaime; Hernáez-Moya, Raquel; Durán, Juan A; Morales, María-Celia

2014-06-01

The aim of this study was to compare the effect on corneal wound healing of 3 differently manufactured blood derivatives [autologous serum (AS), platelet-rich plasma, and serum derived from plasma rich in growth factors (s-PRGF)]. Scratch wound-healing assays were performed on rabbit primary corneal epithelial cultures and human corneal epithelial cells. Additionally, mechanical debridement of rabbit corneal epithelium was performed. Wound-healing progression was assessed by measuring the denuded areas remaining over time after treatment with each of the 3 blood derivatives or a control treatment. In vitro data show statistically significant differences in the healing process with all the derivatives compared with the control, but 2 of them (AS and s-PRGF) induced markedly faster wound healing. In contrast, although the mean time required to complete in vivo reepithelization was similar to that of AS and s-PRGF treatment, only wounds treated with s-PRGF were significantly smaller in size from 2.5 days onward with respect to the control treatment. All 3 blood derivatives studied are promoters of corneal reepithelization. However, the corneal wound-healing progresses differently with each derivative, being faster in vitro under AS and s-PRGF treatment and producing in vivo the greatest decrease in wound size under s-PRGF treatment. These findings highlight that the manufacturing process of the blood derivatives may modulate the efficacy of the final product.

Paired comparison of the sensitivity and specificity of multispectral digital skin lesion analysis and reflectance confocal microscopy in the detection of melanoma in vivo: A cross-sectional study.

PubMed

Song, Eunice; Grant-Kels, Jane M; Swede, Helen; D'Antonio, Jody L; Lachance, Avery; Dadras, Soheil S; Kristjansson, Arni K; Ferenczi, Katalin; Makkar, Hanspaul S; Rothe, Marti J

2016-12-01

Several technologies have been developed to aid dermatologists in the detection of melanoma in vivo including dermoscopy, multispectral digital skin lesion analysis (MDSLA), and reflectance confocal microscopy (RCM). To our knowledge, there have been no studies directly comparing MDSLA and RCM. We conducted a repeated measures analysis comparing the sensitivity and specificity of MDSLA and RCM in the detection of melanoma (n = 55 lesions from 36 patients). Study patients (n = 36) with atypical-appearing pigmented lesions (n = 55) underwent imaging by both RCM and MDSLA. Lesions were biopsied and analyzed by histopathology. RCM exhibited superior test metrics (P = .001, McNemar test) compared with MDSLA. Respectively, sensitivity measures were 85.7% and 71.4%, and specificity rates were 66.7% and 25.0%. The sample size was relatively small and was collected from only one dermatologist's patient base; there was some degree of dermatopathologist interobserver variability; and only one confocalist performed the RCM image evaluations. RCM is a useful adjunct during clinical assessment of in vivo lesions suspicious for melanoma or those requiring re-excision because of high level of dysplasia or having features consistent with an atypical melanocytic nevus with severe cytologic atypia. Copyright © 2016 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

Colorectal tissue engineering: A comparative study between porcine small intestinal submucosa (SIS) and chitosan hydrogel patches.

PubMed

Denost, Quentin; Adam, Jean-Philippe; Pontallier, Arnaud; Montembault, Alexandra; Bareille, Reine; Siadous, Robin; Delmond, Samantha; Rullier, Eric; David, Laurent; Bordenave, Laurence

2015-12-01

Tissue engineering may provide new operative tools for colorectal surgery in elective indications. The aim of this study was to define a suitable bioscaffold for colorectal tissue engineering. We compared 2 bioscaffolds with in vitro and in vivo experiments: porcine small intestinal submucosa (SIS) versus chitosan hydrogel matrix. We assessed nontoxicity of the scaffold in vitro by using human adipose-derived stem cells (hADSC). In vivo, a 1 × 2-cm colonic wall defect was created in 16 rabbits. Animals were divided randomly into 2 groups according to the graft used, SIS or chitosan hydrogel. Graft area was explanted at 4 and 8 weeks. The end points of in vivo experiments were technical feasibility, behavior of the scaffold, in situ putative inflammatory effect, and the quality of tissue regeneration, in particular smooth muscle layer regeneration. In vitro, hADSC attachment and proliferation occurred on both scaffolds without a substantial difference. After proliferation, hADSCs kept their mesenchymal stem cell characteristics. In vivo, one animal died in each group. Eight weeks after implantation, the chitosan scaffold allowed better wound healing compared with the SIS scaffold, with more effective control of inflammatory activity and an integral regeneration of the colonic wall including the smooth muscle cell layer. The outcomes of in vitro experiments did not differ greatly between the 2 groups. Macroscopic and histologic findings, however, revealed better wound healing of the colonic wall in the chitosan group suggesting that the chitosan hydrogel could serve as a better scaffold for colorectal tissue engineering. Copyright © 2015 Elsevier Inc. All rights reserved.

Correlation between positron emission tomography and Cerenkov luminescence imaging in vivo and ex vivo using 64Cu-labeled antibodies in a neuroblastoma mouse model.

PubMed

Maier, Florian C; Schmitt, Julia; Maurer, Andreas; Ehrlichmann, Walter; Reischl, Gerald; Nikolaou, Konstantin; Handgretinger, Rupert; Pichler, Bernd J; Thaiss, Wolfgang M

2016-10-11

Antibody-based therapies gain momentum in clinical therapy, thus the need for accurate imaging modalities with respect to target identification and therapy monitoring are of increasing relevance. Cerenkov luminescence imaging (CLI) are a novel method detecting charged particles emitted during radioactive decay with optical imaging. Here, we compare Position Emission Tomography (PET) with CLI in a multimodal imaging study aiming at the fast and efficient screening of monoclonal antibodies (mAb) designated for targeting of the neuroblastoma-characteristic epitope disialoganglioside GD2. Neuroblastoma-bearing SHO mice were injected with a 64Cu-labeled GD2-specific mAb. The tumor uptake was imaged 3 h, 24 h and 48 h after tracer injection with both, PET and CLI, and was compared to the accumulation in GD2-negative control tumors (human embryonic kidney, HEK-293). In addition to an in vivo PET/CLI-correlation over time, we also demonstrate linear correlations of CLI- and γ-counter-based biodistribution analysis. CLI with its comparably short acquisition time can thus be used as an attractive one-stop-shop modality for the longitudinal monitoring of antibody-based tumor targeting and ex vivo biodistribution.These findings suggest CLI as a reliable alternative for PET and biodistribution studies with respect to fast and high-throughput screenings in subcutaneous tumors traced with radiolabeled antibodies. However, in contrast to PET, CLI is not limited to positron-emitting isotopes and can therefore also be used for the visualization of mAb labeled with therapeutic isotopes like electron emitters.

Comparative effectiveness of Calabadion and sugammadex to reverse non-depolarizing neuromuscular blocking agents

PubMed Central

Haerter, Friederike; Simons, Jeroen Cedric Peter; Foerster, Urs; Duarte, Ingrid Moreno; Diaz-Gil, Daniel; Ganapati, Shweta; Eikermann-Haerter, Katharina; Ayata, Cenk; Zhang, Ben; Blobner, Manfred; Isaacs, Lyle; Eikermann, Matthias

2015-01-01

Background We evaluated the comparative effectiveness of calabadion 2 to reverse non-depolarizing neuromuscular blocking agents (NMBAs) by binding and inactivation. Methods The dose-response relationship of drugs to reverse vecuronium, rocuronium, and cisatracurium-induced neuromuscular block (NMB) was evaluated in vitro (competition binding assays and urine analysis), ex vivo (n=34; phrenic nerve hemidiaphragm preparation) and in vivo (n=108; quadriceps femoris muscle of the rat). Cumulative dose-response curves of calabadions, neostigmine, or sugammadex were created ex vivo at steady-state deep NMB. In living rats, we studied the dose-response relationship of the test drugs to reverse deep block under physiological conditions and we measured the amount of calabadion 2 excreted in the urine. Results In vitro experiments showed that calabadion 2 binds rocuronium with 89 times the affinity of sugammadex (Ka = 3.4 × 109 M−1 and Ka = 3.8 × 107 M−1). Urine analysis (proton nuclear magnetic resonance), competition binding assays and ex vivo study results obtained in the absence of metabolic deactivation are in accordance with an 1:1 binding ratio of sugammadex and calabadion 2 toward rocuronium. In living rats, calabadion 2 dose-dependently and rapidly reversed all NMBAs tested. The molar potency of calabadion 2 to reverse vecuronium and rocuronium was higher compared to sugammadex. Calabadion 2 was eliminated renally, and did not affect blood pressure or heart rate. Conclusion Calabadion 2 reverses NMB-induced by benzylisoquinolines and steroidal NMBAs in rats more effectively, i.e. faster, than sugammadex. Calabadion 2 is eliminated in the urine and well tolerated in rats. PMID:26418697

Sequence, overproduction and purification of Vibrio proteolyticus ribosomal protein L18 for in vitro and in vivo studies

NASA Technical Reports Server (NTRS)

Setterquist, R. A.; Smith, G. K.; Oakley, T. H.; Lee, Y. H.; Fox, G. E.

1996-01-01

A strategy suggested by comparative genomic studies was used to amplify the entire Vibrio proteolyticus (Vp) gene for ribosomal protein L18. Vp L18 and its flanking regions were sequenced and compared with the deduced amino acid (aa) sequences of other known L18 proteins. A 26-aa residue segment at the carboxy terminus contains many strongly conserved residues and may be critical for the L18 interaction with 5S rRNA. This approach should allow rapid characterization of L18 from large numbers of bacteria. Both Vp L18 and Escherichia coli (Ec) L18 were overproduced and purified using a T7 expression vector which fuses an N-terminal peptide segment (His-tag) containing 6 histidine residues to the recombinant protein. The purified fusion proteins, Vp His::L18 and Ec His::L18, were both found to bind to either the Vp 5S or Ec 5S rRNAs in vitro. Vp His::L18 protein was also shown to incorporate into Ec ribosomes in vivo. This His-tag strategy likely will have general applicability for the study of ribosomal proteins in vitro and in vivo.

New Coumarin Derivatives as Potent Selective COX-2 Inhibitors: Synthesis, Anti-Inflammatory, QSAR, and Molecular Modeling Studies.

PubMed

Dawood, Dina H; Batran, Rasha Z; Farghaly, Thoraya A; Khedr, Mohammed A; Abdulla, Mohamed M

2015-12-01

Two new series of coumarin derivatives incorporating thiazoline and thiazolidinone moieties were designed, synthesized, and investigated in vivo for their anti-inflammatory activities using the carrageenan-induced rat paw edema model and in vitro for their inhibitory activities against the human cyclooxygenase (COX)-1 and COX-2 isoforms. Most of the synthesized compounds demonstrated exceptionally high in vivo anti-inflammatory activity and displayed superior GI safety profiles (0-7% ulceration) as compared to indomethacin. All the bioactive compounds showed in vitro high affinity and selectivity toward the COX-2 isoenzyme, compared to the reference celecoxib with IC50 values ranging from 0.31 to 0.78 μM. The ethyl thiosemicarbazone 2b, thiazoline derivatives 3a, 3b, 5b, 6a, and 7f, and the thiazolidinone compounds 8b and 9a showed the highest in vivo and in vitro anti-inflammatory activities with remarkable COX-2 selectivity. Quantitative structure-activity relationship study (QSAR) was done and resulted in a highly predictive power R(2) (0.908). A molecular docking study revealed a relationship between the docking affinity and the biological results. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

In vivo visualization and ex vivo quantification of experimental myocardial infarction by indocyanine green fluorescence imaging

PubMed Central

Sonin, Dmitry; Papayan, Garry; Pochkaeva, Evgeniia; Chefu, Svetlana; Minasian, Sarkis; Kurapeev, Dmitry; Vaage, Jarle; Petrishchev, Nickolay; Galagudza, Michael

2016-01-01

The fluorophore indocyanine green accumulates in areas of ischemia-reperfusion injury due to an increase in vascular permeability and extravasation of the dye. The aim of the study was to validate an indocyanine green-based technique of in vivo visualization of myocardial infarction. A further aim was to quantify infarct size ex vivo and compare this technique with the standard triphenyltetrazolium chloride staining. Wistar rats were subjected to regional myocardial ischemia (30 minutes) followed by reperfusion (n = 7). Indocyanine green (0.25 mg/mL in 1 mL of normal saline) was infused intravenously for 10 minutes starting from the 25th minute of ischemia. Video registration in the near-infrared fluorescence was performed. Epicardial fluorescence of indocyanine green corresponded to the injured area after 30 minutes of reperfusion. Infarct size was similar when determined ex vivo using traditional triphenyltetrazolium chloride assay and indocyanine green fluorescent labeling. Intravital visualization of irreversible injury can be done directly by fluorescence on the surface of the heart. This technique may also be an alternative for ex vivo measurements of infarct size. PMID:28101408

In vivo visualization and ex vivo quantification of experimental myocardial infarction by indocyanine green fluorescence imaging.

PubMed

Sonin, Dmitry; Papayan, Garry; Pochkaeva, Evgeniia; Chefu, Svetlana; Minasian, Sarkis; Kurapeev, Dmitry; Vaage, Jarle; Petrishchev, Nickolay; Galagudza, Michael

2017-01-01

The fluorophore indocyanine green accumulates in areas of ischemia-reperfusion injury due to an increase in vascular permeability and extravasation of the dye. The aim of the study was to validate an indocyanine green-based technique of in vivo visualization of myocardial infarction. A further aim was to quantify infarct size ex vivo and compare this technique with the standard triphenyltetrazolium chloride staining. Wistar rats were subjected to regional myocardial ischemia (30 minutes) followed by reperfusion (n = 7). Indocyanine green (0.25 mg/mL in 1 mL of normal saline) was infused intravenously for 10 minutes starting from the 25th minute of ischemia. Video registration in the near-infrared fluorescence was performed. Epicardial fluorescence of indocyanine green corresponded to the injured area after 30 minutes of reperfusion. Infarct size was similar when determined ex vivo using traditional triphenyltetrazolium chloride assay and indocyanine green fluorescent labeling. Intravital visualization of irreversible injury can be done directly by fluorescence on the surface of the heart. This technique may also be an alternative for ex vivo measurements of infarct size.

In vitro and in vivo mechanical stability of orthodontic mini-implants.

PubMed

Cho, Il-Sik; Kim, Sung-Kyun; Chang, Young-Il; Baek, Seung-Hak

2012-07-01

To compare in vivo and in vitro mechanical stability of orthodontic mini-implants (OMIs) treated with a sandblasted, large-grit, and anodic-oxidation (SLAO) method vs those treated with a sandblasted, large-grit, and acid-etching (SLA) method. Fifty-four titanium OMIs (cylindrical shape, drill-free type; diameter  =  1.45 mm, length  =  8 mm, Biomaterials Korea Inc, Seoul, Korea) were allocated into control, SLA, and SLAO groups (N  =  12 for in vivo and N  =  6 for in vitro studies per group). In vitro study was carried out on a polyurethane foam bone block (Sawbones, Pacific Research Laboratories Inc, Vashon, Wash). In vivo study was performed in the tibias of Beagles (6 males, age  =  1 year, weight  =  10 to 13 kg; OMIs were removed at 8 weeks after installation). For insertion and removal of OMIs, the speed and maximum torque of the surgical engine were set to 30 rpm and 40 Ncm, respectively. Maximum torque (MT), total energy (TE), and near peak energy (NPE) during the insertion and removal procedures were statistically analyzed. In the in vitro study, although the control group had a higher insertion MT value than the SLA and SLAO groups (P < .01), no differences in insertion TE and NPE or in any of the removal variables were noted among the three groups. In the in vivo study, the control group exhibited higher values for all insertion variables compared with the SLA and SLAO groups (MT, P < .001; TE, P < .01; NPE, P < .001). Although no difference in removal TE and removal NPE was noted among the three groups, the SLAO group presented with a higher removal MT than the SLA and control groups (P < .001). SLAO treatment may be an effective tool in reducing insertion damage to surrounding tissue and improving the mechanical stability of OMIs.

A protocol to study ex vivo mouse working heart at human-like heart rate.

PubMed

Feng, Han-Zhong; Jin, Jian-Ping

2018-01-01

Genetically modified mice are widely used as experimental models to study human heart function and diseases. However, the fast rate of normal mouse heart at 400-600bpm limits its capacity of assessing kinetic parameters that are important for the physiology and pathophysiology of human heart that beats at a much slower rate (75-180bpm). To extend the value of mouse models, we established a protocol to study ex vivo mouse working hearts at a human-like heart rate. In the presence of 300μM lidocaine to lower pacemaker and conductive activities and prevent arrhythmia, a stable rate of 120-130bpm at 37°C is achieved for ex vivo mouse working hearts. The negative effects of decreased heart rate on force-frequency dependence and lidocaine as a myocardial depressant on intracellular calcium can be compensated by using a higher but still physiological level of calcium (2.75mM) in the perfusion media. Multiple parameters were studied to compare the function at the human-like heart rate with that of ex vivo mouse working hearts at the standard rate of 480bpm. The results showed that the conditions for slower heart rate in the presence of 300μM lidocaine did not have depressing effect on left ventricular pressure development, systolic and diastolic velocities and stroke volume with maintained positive inotropic and lusitropic responses to β-adrenergic stimulation. Compared with that at 480bpm, the human-like heart rate increased ventricular filling and end diastolic volume with enhanced Frank-Starling responses. Coronary perfusion was increased from longer relaxation time and interval between beats whereas cardiac efficiency was significantly improved. Although the intrinsic differences between mouse and human heart remain, this methodology for ex vivo mouse hearts to work at human-like heart rate extends the value of using genetically modified mouse models to study cardiac function and human heart diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

Validation of NIRS in measuring tissue hemoglobin concentration and oxygen saturation on ex vivo and isolated limb models

NASA Astrophysics Data System (ADS)

Xu, Xiaorong; Zhu, Wen; Padival, Vikram; Xia, Mengna; Cheng, Xuefeng; Bush, Robin; Christenson, Linda; Chan, Tim; Doherty, Tim; Iatridis, Angelo

2003-07-01

Photonify"s tissue spectrometer uses Near-Infrared Spectroscopy for real-time, noninvasive measurement of hemoglobin concentration and oxygen saturation [SO2] of biological tissues. The technology was validated by a series of ex vivo and animal studies. In the ex vivo experiment, a close loop blood circulation system was built, precisely controlling the oxygen saturation and the hemoglobin concentration of a liquid phantom. Photonify"s tissue spectrometer was placed on the surface of the liquid phantom for real time measurement and compared with a gas analyzer, considered the gold standard to measure oxygen saturation and hemoglobin concentration. In the animal experiment, the right hind limb of each dog accepted onto the study was surgically removed. The limb was kept viable by connecting the femoral vein and artery to a blood-primed extracorporeal circuit. Different concentrations of hemoglobin were obtained by adding designated amount of saline solution into the perfusion circuit. Photonify"s tissue spectrometers measured oxygen saturation and hemoglobin concentration at various locations on the limb and compared with gas analyzer results. The test results demonstrated that Photonify"s tissue spectrometers were able to detect the relative changes in tissue oxygen saturation and hemoglobin concentration with a high linear correlation compared to the gas analyzer

A Salmonella Typhimurium-Typhi Genomic Chimera: A Model to Study Vi Polysaccharide Capsule Function In Vivo

PubMed Central

Clare, Simon; Goulding, David; Holt, Kathryn E.; Grant, Andrew J.; Mastroeni, Piero; Dougan, Gordon; Kingsley, Robert A.

2011-01-01

The Vi capsular polysaccharide is a virulence-associated factor expressed by Salmonella enterica serotype Typhi but absent from virtually all other Salmonella serotypes. In order to study this determinant in vivo, we characterised a Vi-positive S. Typhimurium (C5.507 Vi+), harbouring the Salmonella pathogenicity island (SPI)-7, which encodes the Vi locus. S. Typhimurium C5.507 Vi+ colonised and persisted in mice at similar levels compared to the parent strain, S. Typhimurium C5. However, the innate immune response to infection with C5.507 Vi+ and SGB1, an isogenic derivative not expressing Vi, differed markedly. Infection with C5.507 Vi+ resulted in a significant reduction in cellular trafficking of innate immune cells, including PMN and NK cells, compared to SGB1 Vi− infected animals. C5.507 Vi+ infection stimulated reduced numbers of TNF-α, MIP-2 and perforin producing cells compared to SGB1 Vi−. The modulating effect associated with Vi was not observed in MyD88−/− and was reduced in TLR4−/− mice. The presence of the Vi capsule also correlated with induction of the anti-inflammatory cytokine IL-10 in vivo, a factor that impacted on chemotaxis and the activation of immune cells in vitro. PMID:21829346

Vancomycin-Rifampin Combination Therapy Has Enhanced Efficacy against an Experimental Staphylococcus aureus Prosthetic Joint Infection

PubMed Central

Niska, Jared A.; Shahbazian, Jonathan H.; Ramos, Romela Irene; Francis, Kevin P.; Bernthal, Nicholas M.

2013-01-01

Treatment of prosthetic joint infections often involves a two-stage exchange, with implant removal and antibiotic spacer placement followed by systemic antibiotic therapy and delayed reimplantation. However, if antibiotic therapy can be improved, one-stage exchange or implant retention may be more feasible, thereby decreasing morbidity and preserving function. In this study, a mouse model of prosthetic joint infection was used in which Staphylococcus aureus was inoculated into a knee joint containing a surgically placed metallic implant extending from the femur. This model was used to evaluate whether combination therapy of vancomycin plus rifampin has increased efficacy compared with vancomycin alone against these infections. On postoperative day 7, vancomycin with or without rifampin was administered for 6 weeks with implant retention. In vivo bioluminescence imaging, ex vivo CFU enumeration, X-ray imaging, and histologic analysis were carried out. We found that there was a marked therapeutic benefit when vancomycin was combined with rifampin compared with vancomycin alone. Taken together, our results suggest that the mouse model used could serve as a valuable in vivo preclinical model system to evaluate and compare efficacies of antibiotics and combinatory therapy for prosthetic joint infections before more extensive studies are carried out in human subjects. PMID:23917317

The effect of a dual or a triple antithrombotic therapy with apixaban on thrombus formation in vivo and in an ex vivo perfusion chamber model

PubMed Central

Weisshaar, Stefan; Litschauer, Brigitte; Bucher, Sebastian; Riesenhuber, Martin; Kapiotis, Stylianos; Kyrle, Paul Alexander; Wolzt, Michael

2016-01-01

Abstract Background: There is a need to optimize pharmacological treatment in patients with acute coronary syndrome and concomitant atrial fibrillation, in particular with newer antithrombotic medicines. We have therefore studied if dual or triple combination of antithrombotic agents exert similar effects on coagulation activation in an in vivo model in the skin microvasculature and in an ex vivo perfusion chamber. Methods and Results: Shed blood platelet activation (β-thromboglobulin [β-TG]), thrombin generation (thrombin-antithrombin complex [TAT]) and volume as well as markers of thrombus size (D-dimer) and its platelet content (P-selectin) in a perfusion chamber were studied in a sequential, open-label, parallel group trial in 40 healthy male volunteers (n = 20 per group). Subjects received ticagrelor and apixaban without or with acetylsalicylic acid (ASA). Outcome parameters were assessed at 3 hours after therapy dosing, and at steady-state trough and peak conditions. A triple or dual therapy induced a comparable decrease in shed blood β-TG at 3 hours after therapy dosing but was more pronounced at steady-state conditions with the more intense treatment combination. During both antithrombotic regimens a similarly sustained inhibition in thrombin generation was observed which was accompanied by comparable increases in shed blood volume. In contrast, no treatment effect could be observed in the perfusion chamber experiment. Conclusion: Ticagrelor and apixaban with or without ASA inhibit platelet activation and thrombin formation in vivo in healthy subjects. Platelet inhibition was greater at steady-state conditions after triple therapy administration. PMID:27399131

The Cryptococcus neoformans Transcriptome at the Site of Human Meningitis

PubMed Central

Chen, Yuan; Toffaletti, Dena L.; Tenor, Jennifer L.; Litvintseva, Anastasia P.; Fang, Charles; Mitchell, Thomas G.; McDonald, Tami R.; Nielsen, Kirsten; Boulware, David R.; Bicanic, Tihana; Perfect, John R.

2014-01-01

ABSTRACT Cryptococcus neoformans is the leading cause of fungal meningitis worldwide. Previous studies have characterized the cryptococcal transcriptome under various stress conditions, but a comprehensive profile of the C. neoformans transcriptome in the human host has not been attempted. Here, we extracted RNA from yeast cells taken directly from the cerebrospinal fluid (CSF) of two AIDS patients with cryptococcal meningitis prior to antifungal therapy. The patients were infected with strains of C. neoformans var. grubii of molecular type VNI and VNII. Using RNA-seq, we compared the transcriptional profiles of these strains under three environmental conditions (in vivo CSF, ex vivo CSF, and yeast extract-peptone-dextrose [YPD]). Although we identified a number of differentially expressed genes, single nucleotide variants, and novel genes that were unique to each strain, the overall expression patterns of the two strains were similar under the same environmental conditions. Specifically, yeast cells obtained directly from each patient’s CSF were more metabolically active than cells that were incubated ex vivo in CSF. Compared with growth in YPD, some genes were identified as significantly upregulated in both in vivo and ex vivo CSF, and they were associated with genes previously recognized for contributing to pathogenicity. For example, genes with known stress response functions, such as RIM101, ENA1, and CFO1, were regulated similarly in the two clinical strains. Conversely, many genes that were differentially regulated between the two strains appeared to be transporters. These findings establish a platform for further studies of how this yeast survives and produces disease. PMID:24496797

In-vivo detectability index: development and validation of an automated methodology

NASA Astrophysics Data System (ADS)

Smith, Taylor Brunton; Solomon, Justin; Samei, Ehsan

2017-03-01

The purpose of this study was to develop and validate a method to estimate patient-specific detectability indices directly from patients' CT images (i.e., "in vivo"). The method works by automatically extracting noise (NPS) and resolution (MTF) properties from each patient's CT series based on previously validated techniques. Patient images are thresholded into skin-air interfaces to form edge-spread functions, which are further binned, differentiated, and Fourier transformed to form the MTF. The NPS is likewise estimated from uniform areas of the image. These are combined with assumed task functions (reference function: 10 mm disk lesion with contrast of -15 HU) to compute detectability indices for a non-prewhitening matched filter model observer predicting observer performance. The results were compared to those from a previous human detection study on 105 subtle, hypo-attenuating liver lesions, using a two-alternative-forcedchoice (2AFC) method, over 6 dose levels using 16 readers. The in vivo detectability indices estimated for all patient images were compared to binary 2AFC outcomes with a generalized linear mixed-effects statistical model (Probit link function, linear terms only, no interactions, random term for readers). The model showed that the in vivo detectability indices were strongly predictive of 2AFC outcomes (P < 0.05). A linear comparison between the human detection accuracy and model-predicted detection accuracy (for like conditions) resulted in Pearson and Spearman correlations coefficients of 0.86 and 0.87, respectively. These data provide evidence that the in vivo detectability index could potentially be used to automatically estimate and track image quality in a clinical operation.

The Effectiveness of Bacteriophages against Methicillin-Resistant Staphylococcus aureus ST398 Nasal Colonization in Pigs.

PubMed

Verstappen, Koen M; Tulinski, Pawel; Duim, Birgitta; Fluit, Ad C; Carney, Jennifer; van Nes, Arie; Wagenaar, Jaap A

2016-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) is an important colonizer in animals and an opportunistic pathogen in humans. In humans, MRSA can cause infections that might be difficult to treat because of antimicrobial resistance. The use of bacteriophages has been suggested as a potential approach for the control of MRSA colonization to minimize the-often occupational-exposure of humans. The aim of this study was to assess the efficacy of bacteriophage treatment on porcine nasal colonization with MRSA in vitro, in vivo, and ex vivo. The effectiveness of a bacteriophage combination of phage K*710 and P68 was assessed in vitro by incubating them with MRSA V0608892/1 (ST398) measuring the OD600 hourly. To study the in vivo effect, bacteriophages were administered in a gel developed for human application, which contain 109 plaque-forming units (pfu)/mL (K and P68 in a 19.25:1 ratio) for 5 days to piglets (N = 8) that were experimentally colonized with the MRSA strain. Eight piglets experimentally colonized were used as a negative control. The MRSA strain was also used to colonize porcine nasal mucosa explants and bacteriophages were applied to assess the ex vivo efficacy of treatment. Bacteriophages were effective in vitro. In vivo, sixteen piglets were colonized with MRSA but the number of CFU recovered after the application of the bacteriophages in 8 piglets was not reduced compared to the control animals (approx. 105 CFU/swab). In the ex vivo model, 108 CFU were used to establish colonization with MRSA; a reduction of colonization was not observed after application of bacteriophages. However, application of mupirocin both in vivo and ex vivo resulted in a near eradication of MRSA. i) The MRSA strain was killed in the presence of the bacteriophages phage K*710 and P68 in vitro. ii) Bacteriophages did not reduce porcine nasal colonization in vivo or ex vivo. Physiological in vivo and ex vivo conditions may explain these observations. Efficacy in the ex vivo model matched that of the in vivo system.

The Effectiveness of Bacteriophages against Methicillin-Resistant Staphylococcus aureus ST398 Nasal Colonization in Pigs

PubMed Central

Duim, Birgitta; Fluit, Ad C; Carney, Jennifer; van Nes, Arie; Wagenaar, Jaap A

2016-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) is an important colonizer in animals and an opportunistic pathogen in humans. In humans, MRSA can cause infections that might be difficult to treat because of antimicrobial resistance. The use of bacteriophages has been suggested as a potential approach for the control of MRSA colonization to minimize the—often occupational—exposure of humans. The aim of this study was to assess the efficacy of bacteriophage treatment on porcine nasal colonization with MRSA in vitro, in vivo, and ex vivo. The effectiveness of a bacteriophage combination of phage K*710 and P68 was assessed in vitro by incubating them with MRSA V0608892/1 (ST398) measuring the OD600 hourly. To study the in vivo effect, bacteriophages were administered in a gel developed for human application, which contain 109 plaque-forming units (pfu)/mL (K and P68 in a 19.25:1 ratio) for 5 days to piglets (N = 8) that were experimentally colonized with the MRSA strain. Eight piglets experimentally colonized were used as a negative control. The MRSA strain was also used to colonize porcine nasal mucosa explants and bacteriophages were applied to assess the ex vivo efficacy of treatment. Bacteriophages were effective in vitro. In vivo, sixteen piglets were colonized with MRSA but the number of CFU recovered after the application of the bacteriophages in 8 piglets was not reduced compared to the control animals (approx. 105 CFU/swab). In the ex vivo model, 108 CFU were used to establish colonization with MRSA; a reduction of colonization was not observed after application of bacteriophages. However, application of mupirocin both in vivo and ex vivo resulted in a near eradication of MRSA. In conclusion: i) The MRSA strain was killed in the presence of the bacteriophages phage K*710 and P68 in vitro. ii) Bacteriophages did not reduce porcine nasal colonization in vivo or ex vivo. Physiological in vivo and ex vivo conditions may explain these observations. Efficacy in the ex vivo model matched that of the in vivo system. PMID:27487020

Use of ex vivo and in vitro cultures of the human respiratory tract to study the tropism and host responses of highly pathogenic avian influenza A (H5N1) and other influenza viruses.

PubMed

Chan, Renee W Y; Chan, Michael C W; Nicholls, John M; Malik Peiris, J S

2013-12-05

The tropism of influenza viruses for the human respiratory tract is a key determinant of host-range, and consequently, of pathogenesis and transmission. Insights can be obtained from clinical and autopsy studies of human disease and relevant animal models. Ex vivo cultures of the human respiratory tract and in vitro cultures of primary human cells can provide complementary information provided they are physiologically comparable in relevant characteristics to human tissues in vivo, e.g. virus receptor distribution, state of differentiation. We review different experimental models for their physiological relevance and summarize available data using these cultures in relation to highly pathogenic avian influenza H5N1, in comparison where relevant, with other influenza viruses. Transformed continuous cell-lines often differ in important ways to the corresponding tissues in vivo. The state of differentiation of primary human cells (respiratory epithelium, macrophages) can markedly affect virus tropism and host responses. Ex vivo cultures of human respiratory tissues provide a close resemblance to tissues in vivo and may be used to risk assess animal viruses for pandemic threat. Physiological factors (age, inflammation) can markedly affect virus receptor expression and virus tropism. Taken together with data from clinical studies on infected humans and relevant animal models, data from ex vivo and in vitro cultures of human tissues and cells can provide insights into virus transmission and pathogenesis and may provide understanding that leads to novel therapeutic interventions. Copyright © 2013 Elsevier B.V. All rights reserved.

Differential Expression of In Vivo and In Vitro Protein Profile of Outer Membrane of Acidovorax avenae Subsp. avenae

PubMed Central

Qiu, Hui; Li, Bin; Jabeen, Amara; Li, Liping; Liu, He; Kube, Michael; Xie, Guanlin; Wang, Yanli; Sun, Guochang

2012-01-01

Outer membrane (OM) proteins play a significant role in bacterial pathogenesis. In this work, we examined and compared the expression of the OM proteins of the rice pathogen Acidovorax avenae subsp. avenae strain RS-1, a Gram-negative bacterium, both in an in vitro culture medium and in vivo rice plants. Global proteomic profiling of A. avenae subsp. avenae strain RS-1 comparing in vivo and in vitro conditions revealed the differential expression of proteins affecting the survival and pathogenicity of the rice pathogen in host plants. The shotgun proteomics analysis of OM proteins resulted in the identification of 97 proteins in vitro and 62 proteins in vivo by mass spectrometry. Among these OM proteins, there is a high number of porins, TonB-dependent receptors, lipoproteins of the NodT family, ABC transporters, flagellins, and proteins of unknown function expressed under both conditions. However, the major proteins such as phospholipase and OmpA domain containing proteins were expressed in vitro, while the proteins such as the surface anchored protein F, ATP-dependent Clp protease, OmpA and MotB domain containing proteins were expressed in vivo. This may indicate that these in vivo OM proteins have roles in the pathogenicity of A. avenae subsp. avenae strain RS-1. In addition, the LC-MS/MS identification of OmpA and MotB validated the in silico prediction of the existance of Type VI secretion system core components. To the best of our knowledge, this is the first study to reveal the in vitro and in vivo protein profiles, in combination with LC-MS/MS mass spectra, in silico OM proteome and in silico genome wide analysis, of pathogenicity or plant host required proteins of a plant pathogenic bacterium. PMID:23166741

In Vivo MRI Evidence that Neuropathology is Attenuated by Cognitive Enrichment in the Yac128 Huntington's Disease Mouse Model.

PubMed

Steventon, Jessica J; Harrison, David J; Trueman, Rebecca C; Rosser, Anne E; Jones, Derek K; Brooks, Simon P

2015-01-01

Environmental enrichment has been shown to improve symptoms and reduce neuropathology in mouse models of Huntington's disease (HD); however results are limited to ex vivo techniques with associated shortcomings. In-vivo magnetic resonance imaging (MRI) can overcome some of the shortcomings and is applied for the first time here to assess the effect of a cognitive intervention in a mouse model of HD. We aimed to investigate whether in-vivo high-field MRI can detect a disease-modifying effect in tissue macrostructure following a cognitive enrichment regime. YAC128 transgenic and wild type mice were exposed to cognitive enrichment throughout their lifetime. At 20-months old, mice were scanned with a T2-weighted MRI sequence and a region-of-interest (ROI) approach was used to examine structural changes. Locomotor activity and performance on the rotarod and serial discrimination watermaze task were assessed to measure motor and cognitive function respectively. Mice exposed to cognitive enrichment were more active and able to stay on a rotating rod longer compared to control mice, with comparable rotarod performance between HD enriched mice and wild-type mice. YAC128 mice demonstrated cognitive impairments which were not improved by cognitive enrichment. In-vivo MRI revealed a reduction in the degree of caudate-putamen atrophy in the enriched HD mice. We provide in vivo evidence of a beneficial effect of environmental enrichment on neuropathology and motor function in a HD mouse model. This demonstrates the efficacy of MRI in a model of HD and provides the basis for an in-vivo non-destructive outcome measure necessary for longitudinal study designs to understand the effect of enrichment with disease progression.

The in vivo disposition and in vitro transmembrane transport of two model radiometabolites of DOTA-conjugated receptor-specific peptides labelled with (177) Lu.

PubMed

Volková, Marie; Mandíková, Jana; Bárta, Pavel; Navrátilová, Lucie; Lázníčková, Alice; Trejtnar, František

2015-01-01

In vivo metabolism of the radiolabelled receptor-specific peptides has been described; however, information regarding the pharmacokinetic behaviour of the degradation products within the body is very scarce. The present study was designed to obtain new knowledge on the disposition and elimination of low-molecular radiometabolites of receptor-specific peptides in the organism and to reveal the potential involvement of selected membrane transport mechanisms in the cellular uptake of radiometabolites, especially in the kidney. The study compared pharmacokinetics of two radiometabolites: a final metabolite of somatostatin analogues, (177)Lu-DOTA-DPhe, and a tripeptide metabolite of (177)Lu-DOTA-minigastrin 11, (177)Lu-DOTA-DGlu-Ala-Tyr. Their pharmacokinetics was compared with that of respective parent (177)Lu-radiopeptide. Both radiometabolites exhibited relative rapid clearing from most body tissues in rats in vivo along with predominant renal excretion. The long-term renal retention of the smaller radiometabolite (177)Lu-DOTA-DPhe was lower than that of (177)Lu-DOTA-DGlu-Ala-Tyr. An uptake of (177)Lu-DOTA-DPhe by human renal influx transporter organic cation transporter 2 was found in vitro in a cellular model. The study brings the first experimental data on the in vivo pharmacokinetics of radiometabolites of receptor-specific somatostatin and gastrin analogues. The found results may indicate a negative correlation between the degree of decomposition of the parent peptide chain and the renal retention of the metabolite. Copyright © 2015 John Wiley & Sons, Ltd.

In vivo evaluation of thiolated chitosan tablets for oral insulin delivery.

PubMed

Millotti, Gioconda; Laffleur, Flavia; Perera, Glen; Vigl, Claudia; Pickl, Karin; Sinner, Frank; Bernkop-Schnürch, Andreas

2014-10-01

Chitosan-6-mercaptonicotinic acid (chitosan-6-MNA) is a thiolated chitosan with strong mucoadhesive properties and a pH-independent reactivity. This study aimed to evaluate the in vivo potential for the oral delivery of insulin. The comparison of the nonconjugated chitosan and chitosan-6-MNA was performed on several studies such as mucoadhesion, release, and in vivo studies. Thiolated chitosan formulations were both about 80-fold more mucoadhesive compared with unmodified ones. The thiolated chitosan tablets showed a sustained release for 5 h for the polymer of 20 kDa and 8 h for the polymer of 400 kDa. Human insulin was quantified in rats' plasma by means of ELISA specific for human insulin with no cross-reactivity with the endogenous insulin. In vivo results showed thiolation having a tremendous impact on the absorption of insulin. The absolute bioavailabilities were 0.73% for chitosan-6-MNA of 20 kDa and 0.62% for chitosan-6-MNA 400 kDa. The areas under the concentration-time curves (AUC) of chitosan-6-MNA formulations compared with unmodified chitosan were 4.8-fold improved for the polymer of 20 kDa and 21.02-fold improved for the polymer of 400 kDa. The improvement in the AUC with regard to the most promising aliphatic thiomer was up to 6.8-fold. Therefore, chitosan-6-MNA represents a promising excipient for the oral delivery of insulin. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

Formulation and In-vivo Pharmacokinetic Consideration of Intranasal Microemulsion and Mucoadhesive Microemulsion of Rivastigmine for Brain Targeting.

PubMed

Shah, Brijesh; Khunt, Dignesh; Misra, Manju; Padh, Harish

2018-01-02

Presence of tight junctions in blood brain barrier (BBB) pose a major hurdle for delivery of drug and severely affects adequate therapeutic concentration to reach the brain. In present work, we have selected Rivastigmine hydrogen tartrate (RHT), a reversible cholinesterase inhibitor, which exhibits extensive first-pass metabolism, resulting in limited absolute bioavailability (36%). RHT shows extremely low aqueous solubility and poor penetration, resulting in inadequate concentration reaching the brain, thus necessitating frequent oral dosing. To overcome these problems of RHT, microemulsion (ME) and mucoadhesive microemulsion (MME) of RHT were formulated for brain targeting via intranasal delivery route and compared on the basis of in vivo pharmacokinetics. ME and MME formulations containing RHT were developed by water titration method. Characterization of ME and MME was done for various physicochemical parameters, nasal spray pattern, and in vivo pharmacokinetics quantitatively and qualitatively (gamma scintigraphy studies). The developed ME and MME were transparent having globule size approximately in the range of 53-55 nm. Pharmacokinetic studies showed higher values for C max and DTP for intranasal RHT: CH-ME over RHT-ME, thus indicating the effect of chitosan in modulating tight junctions, thereby enhanced paracellular transport of RHT. Gamma scintigraphy and in vivo pharmacokinetic study suggested enhanced RHT concentration, upon intranasal administration of RHT:CH-ME, compare with other groups administered formulations intranasally. These findings suggested the potential of non-invasive intranasal route for brain delivery, especially for therapeutics, facing challenges in oral administration.

Comparison of N-terminal modifications on neurotensin(8-13) analogues correlates peptide stability but not binding affinity with in vivo efficacy.

PubMed

Orwig, Kevin S; Lassetter, McKensie R; Hadden, M Kyle; Dix, Thomas A

2009-04-09

Neurotensin(8-13) and two related analogues were used as model systems to directly compare various N-terminal peptide modifications representing both commonly used and novel capping groups. Each N-terminal modification prevented aminopeptidase cleavage but surprisingly differed in its ability to inhibit cleavage at other sites, a phenomenon attributed to long-range conformational effects. None of the capping groups were inherently detrimental to human neurotensin receptor 1 (hNTR1) binding affinity or receptor agonism. Although the most stable peptides exhibited the lowest binding affinities and were the least potent receptor agonists, they produced the largest in vivo effects. Of the parameters studied only stability significantly correlated with in vivo efficacy, demonstrating that a reduction in binding affinity at NTR1 can be countered by increased in vivo stability.

Confocal microscopy for astrocyte in vivo imaging: Recycle and reuse in microscopy

PubMed Central

Pérez-Alvarez, Alberto; Araque, Alfonso; Martín, Eduardo D.

2013-01-01

In vivo imaging is one of the ultimate and fundamental approaches for the study of the brain. Two-photon laser scanning microscopy (2PLSM) constitutes the state-of-the-art technique in current neuroscience to address questions regarding brain cell structure, development and function, blood flow regulation and metabolism. This technique evolved from laser scanning confocal microscopy (LSCM), which impacted the field with a major improvement in image resolution of live tissues in the 1980s compared to widefield microscopy. While nowadays some of the unparalleled features of 2PLSM make it the tool of choice for brain studies in vivo, such as the possibility to image deep within a tissue, LSCM can still be useful in this matter. Here we discuss the validity and limitations of LSCM and provide a guide to perform high-resolution in vivo imaging of the brain of live rodents with minimal mechanical disruption employing LSCM. We describe the surgical procedure and experimental setup that allowed us to record intracellular calcium variations in astrocytes evoked by sensory stimulation, and to monitor intact neuronal dendritic spines and astrocytic processes as well as blood vessel dynamics. Therefore, in spite of certain limitations that need to be carefully considered, LSCM constitutes a useful, convenient, and affordable tool for brain studies in vivo. PMID:23658537

In-vivo NMR studies of deuterium-labeled photosensitizers in mice tumor model

NASA Astrophysics Data System (ADS)

Ramaprasad, Subbaraya; Liu, Y. H.; Pandey, R. K.; Shiau, Fuu-Yau; Smith, Kevin M.

1993-06-01

Photodynamic therapy (PDT) has emerged as a promising modality for the treatment of cancer. We are using newly synthesized and chemically defined and characterized porphyrin photosensitizers that are specifically labeled with deuterium to perform in vivo NMR studies in a murine tumor model. In vivo magnetic resonance offers the potential for repetitive, safe, noninvasive evaluation of photosensitizers, tumor metabolism, and the effect of PDT on the tumor metabolism. In an effort to monitor noninvasively the photosensitizers in an in vivo tumor model, we are synthesizing several deuterium labeled photosensitizers which absorb red light at or above 630 nm. Development of methods to test these photosensitizers directly in humans is not feasible at this time, since these photosensitizers are new and we do not yet understand the side effects. In addition, we do not understand the potential benefits compared with Photofrin II, the widely used photosensitizer. To perform our in vivo deuterium NMR studies on mouse foot tumors, we have constructed a solenoid coil which operates at 30.7 MHz for the deuterium nucleus. We have been able to detect the deuterium labeled photosensitizer in the tumor after a direct intra-tumor injection. The use of 31P NMR to predict the possible outcome of PDT in these tumors is also discussed.

Ocular Toxicity Profile of ST-162 and ST-168 as Novel Bifunctional MEK/PI3K Inhibitors.

PubMed

Smith, Andrew; Pawar, Mercy; Van Dort, Marcian E; Galbán, Stefanie; Welton, Amanda R; Thurber, Greg M; Ross, Brian D; Besirli, Cagri G

2018-04-30

ST-162 and ST-168 are small-molecule bifunctional inhibitors of MEK and PI3K signaling pathways that are being developed as novel antitumor agents. Previous small-molecule and biologic MEK inhibitors demonstrated ocular toxicity events that were dose limiting in clinical studies. We evaluated in vitro and in vivo ocular toxicity profiles of ST-162 and ST-168. Photoreceptor cell line 661W and adult retinal pigment epithelium cell line ARPE-19 were treated with increasing concentrations of bifunctional inhibitors. Western blots, cell viability, and caspase activity assays were performed to evaluate MEK and PI3K inhibition and dose-dependent in vitro toxicity, and compared with monotherapy. In vivo toxicity profile was assessed by intravitreal injection of ST-162 and ST-168 in Dutch-Belted rabbits, followed by ocular examination and histological analysis of enucleated eyes. Retinal cell lines treated with ST-162 or ST-168 exhibited dose-dependent inhibition of MEK and PI3K signaling. Compared with inhibition by monotherapies and their combinations, bifunctional inhibitors demonstrated reduced cell death and caspase activity. In vivo, both bifunctional inhibitors exhibited a more favorable toxicity profile when compared with MEK inhibitor PD0325901. Novel MEK and PI3K bifunctional inhibitors ST-162 and ST-168 demonstrate favorable in vitro and in vivo ocular toxicity profiles, supporting their further development as potential therapeutic agents targeting multiple aggressive tumors.

Biotransformation of the mycotoxin enniatin B1 in pigs: A comparative in vitro and in vivo approach.

PubMed

Ivanova, Lada; Uhlig, Silvio; Devreese, Mathias; Croubels, Siska; Fæste, Christiane Kruse

2017-07-01

Enniatins (ENNs) are hexadepsipeptidic mycotoxins produced by Fusarium species. They occur in mg/kg levels in grain from Northern climate areas. Major ENNs such as ENN B and B1 have shown considerable cytotoxicity in different in vitro test systems. To adequately assess exposure and in vivo toxicity the toxicokinetic properties need to be investigated. The present study describes the metabolism of ENN B1 both in vitro and in vivo in pigs, comparing metabolites found in vitro in experiments with liver microsomes from different pig strains to those found in the plasma of pigs after single oral or intravenous application of ENN B1. Metabolites of hepatic biotransformation were tentatively identified and characterised by high performance liquid chromatography coupled to ion trap and high-resolution mass spectrometry, as well as chemical derivatisations. Kinetic parameters of metabolite formation and elimination were determined. Metabolite formation was higher when ENN B1 was absorbed from the gut compared to intravenous administration indicating pre-systemic metabolism of ENN B1 after oral uptake. The in vitro approach resulted in the detection of ten ENN B1 metabolites, while six were detected in in vivo samples. The putative ENN B1 metabolites were products of hydroxylation, carbonylation, carboxylation and oxidative demethylation reactions. Copyright © 2017. Published by Elsevier Ltd.

A Clinical Evaluation of Cone Beam Computed Tomography

DTIC Science & Technology

2013-07-31

body of literature lacks in vivo studies comparing CBCT images with clinical findings. The purpose of this descriptive case series was to...All (18/18) bone measurements were underrepresented on CBCT images in this study . This case series also identified limitations in accuracy when... study was to compare pre-surgical CBCT images against the actual clinical presentation of the hard tissues. METHOD: Eleven patients requiring

Comparison of In-Vitro and Ex-Vivo Wound Healing Assays for the Investigation of Diabetic Wound Healing and Demonstration of a Beneficial Effect of a Triterpene Extract

PubMed Central

Ueck, Christopher; Volksdorf, Thomas; Houdek, Pia; Vidal-y-Sy, Sabine; Sehner, Susanne; Ellinger, Bernhard; Lobmann, Ralf; Larena-Avellaneda, Axel; Reinshagen, Konrad; Ridderbusch, Ina; Kohrmeyer, Klaas; Moll, Ingrid; Daniels, Rolf; Werner, Philipp; Merfort, Irmgard; Brandner, Johanna M.

2017-01-01

Diabetes mellitus is a frequent cause for chronic, difficult-to-treat wounds. New therapies for diabetic wounds are urgently needed and in-vitro or ex-vivo test systems are essential for the initial identification of new active molecules. The aim of this study is to compare in-vitro and ex-vivo test systems for their usability for early drug screening and to investigate the efficacy of a birch bark triterpene extract (TE) that has been proven ex-vivo and clinically to accelerate non-diabetic wound healing (WH), in a diabetic context. We investigated in-vitro models for diabetic WH, i.e. scratch assays with human keratinocytes from diabetic donors or cultured under hyperglycaemic conditions and a newly developed porcine ex-vivo hyperglycaemic WH model for their potential to mimic delayed diabetic WH and for the influence of TE in these test systems. We show that keratinocytes from diabetic donors often fail to exhibit significantly delayed WH. For cells under hyperglycaemic conditions significant decrease is observed but is influenced by choice of medium and presence of supplements. Also, donor age plays a role. Interestingly, hyperglycaemic effects are mainly hyperosmolaric effects in scratch assays. Ex-vivo models under hyperglycaemic conditions show a clear and substantial decrease of WH, and here both glucose and hyperosmolarity effects are involved. Finally, we provide evidence that TE is also beneficial for ex-vivo hyperglycaemic WH, resulting in significantly increased length of regenerated epidermis to 188±16% and 183±11% (SEM; p<0.05) compared to controls when using two different TE formulations. In conclusion, our results suggest that microenvironmental influences are important in WH test systems and that therefore the more complex hyperglycaemic ex-vivo model is more suitable for early drug screening. Limitations of the in-vitro and ex-vivo models are discussed. Furthermore our data recommend TE as a promising candidate for in-vivo testings in diabetic wounds. PMID:28046026

Gold nanoparticles as a contrast agent for in vivo tumor imaging with photoacoustic tomography

NASA Astrophysics Data System (ADS)

Zhang, Q.; Iwakuma, N.; Sharma, P.; Moudgil, B. M.; Wu, C.; McNeill, J.; Jiang, H.; Grobmyer, S. R.

2009-09-01

Photoacoustic tomography (PAT) is a rapidly emerging non-invasive imaging technology that integrates the merits of high optical contrast with high ultrasound resolution. The ability to quantitatively and non-invasively image nanoparticles has important implications for the development of nanoparticles as in vivo cancer diagnostic and therapeutic agents. In this study, the ability of systemically administered poly(ethylene glycol)-coated (PEGylated) gold nanoparticles as a contrast agent for in vivo tumor imaging with PAT has been evaluated. We demonstrate that gold nanoparticles (20 and 50 nm) have high photoacoustic contrast as compared to mouse tissue ex vivo. Gold nanoparticles can be visualized in mice in vivo following subcutaneous administration using PAT. Following intravenous administration of PEGylated gold nanoparticles to tumor-bearing mice, accumulation of gold nanoparticles in tumors can be effectively imaged with PAT. With gold nanoparticles as a contrast agent, PAT has important potential applications in the image guided therapy of superficial tumors such as breast cancer, melanoma and Merkel cell carcinoma.

Widefield quantitative multiplex surface enhanced Raman scattering imaging in vivo

NASA Astrophysics Data System (ADS)

McVeigh, Patrick Z.; Mallia, Rupananda J.; Veilleux, Israel; Wilson, Brian C.

2013-04-01

In recent years numerous studies have shown the potential advantages of molecular imaging in vitro and in vivo using contrast agents based on surface enhanced Raman scattering (SERS), however the low throughput of traditional point-scanned imaging methodologies have limited their use in biological imaging. In this work we demonstrate that direct widefield Raman imaging based on a tunable filter is capable of quantitative multiplex SERS imaging in vivo, and that this imaging is possible with acquisition times which are orders of magnitude lower than achievable with comparable point-scanned methodologies. The system, designed for small animal imaging, has a linear response from (0.01 to 100 pM), acquires typical in vivo images in <10 s, and with suitable SERS reporter molecules is capable of multiplex imaging without compensation for spectral overlap. To demonstrate the utility of widefield Raman imaging in biological applications, we show quantitative imaging of four simultaneous SERS reporter molecules in vivo with resulting probe quantification that is in excellent agreement with known quantities (R2>0.98).

Histological study on the effects of microablative fractional CO2 laser on atrophic vaginal tissue: an ex vivo study.

PubMed

Salvatore, Stefano; Leone Roberti Maggiore, Umberto; Athanasiou, Stavros; Origoni, Massimo; Candiani, Massimo; Calligaro, Alberto; Zerbinati, Nicola

2015-08-01

Microablative fractional CO2 laser has been proven to determine tissue remodeling with neoformation of collagen and elastic fibers on atrophic skin. The aim of our study is to evaluate the effects of microablative fractional CO2 laser on postmenopausal women with vulvovaginal atrophy using an ex vivo model. This is a prospective ex vivo cohort trial. Consecutive postmenopausal women with vulvovaginal atrophy managed with pelvic organ prolapse surgical operation were enrolled. After fascial plication, the redundant vaginal edge on one side was treated with CO2 laser (SmartXide2; DEKA Laser, Florence, Italy). Five different CO2 laser setup protocols were tested. The contralateral part of the vaginal wall was always used as control. Excessive vagina was trimmed and sent for histological evaluation to compare treated and nontreated tissues. Microscopic and ultrastructural aspects of the collagenic and elastic components of the matrix were studied, and a specific image analysis with computerized morphometry was performed. We also considered the fine cytological aspects of connective tissue proper cells, particularly fibroblasts. During the study period, five women were enrolled, and 10 vaginal specimens were finally retrieved. Four different settings of CO2 laser were compared. Protocols were tested twice each to confirm histological findings. Treatment protocols were compared according to histological findings, particularly in maximal depth and connective changes achieved. All procedures were uneventful for participants. This study shows that microablative fractional CO2 laser can produce a remodeling of vaginal connective tissue without causing damage to surrounding tissue.

Application of Ulex europaeus agglutinin I-modified liposomes for oral vaccine: Ex Vivo bioadhesion and in Vivo immunity.

PubMed

Li, KeXin; Zhao, Xiuli; Xu, Shiyi; Pang, DaHai; Yang, ChunRong; Chen, DaWei

2011-01-01

The conjugation of Ulex europaeus agglutinin I (UEAI) onto surface of liposomes has been demonstrated to effectively improve the intestinal absorption of antigen, subsequently induced strong mucosal and systemic immune responses. In this context, we prepared bovine serum albumin (BSA)-encapsulating UEAI-modified liposomes (UEAI-LIP) and unmodified ones (LIP). The specific bioadhesion on mice gastro-intestinal mucosa was studied ex vivo. An important increase of interaction between UEAI-conjugated liposomes and the intestinal segments with Peyer's Patches (PPs) was observed compared with the unconjugated one (p<0.01). However, under the presence of α-L-fucose, which is the reported specific sugar for UEAI, specifically inhibited the activity of these conjugates. The immune-stimulating activity in vivo was studied by measuring immunoglobulin G (IgG) levels in serum and immunoglobulin A (IgA) levels in intestinal mucosal secretions following oral administration of BSA solution, LIP and UEAI-LIP in mice. Results indicate that antigen encapsulated in liposomes, especially the UEAI-modified ones, was favorable for inducing immune response. At 42 d after the first immunization, the highest IgG and IgA antibody levels produced by UEAI-LIP occurred, respectively showing 4.4-fold and 5-fold higher levels compared to those of the groups receiving BSA alone. This data demonstrated high potential of UEAI-modified liposomes for their use as carrier for oral vaccines.

Effects of short malunion of the clavicle on in vivo scapular kinematics.

PubMed

Kim, DooSup; Lee, DongWoo; Jang, YoungHwan; Yeom, JunSeop; Banks, Scott A

2017-09-01

Short malunion of the clavicle after fracture can change scapular kinematics and alter clinical outcome. However, the effects of malunion on kinematics and outcomes remains poorly understood because there have been no in vivo studies measuring changes during active motion with malunion. This study aimed to measure and to compare in vivo 3-dimensional (3D) scapular kinematics between normal shoulders and shoulders with short malunion using 3D-2-dimensional model image registration techniques. Fifteen patients with clavicle fracture who had been treated conservatively were enrolled in this study. In these patients, the angle of scapular upward rotation, posterior tilting, and external rotation were compared between shoulders with short malunion and contralateral, normal shoulders. A 3D-2-dimensional model image registration technique was used to determine the 3D orientation of the scapula. Scapular upward rotation increased following increase of the arm elevation angle and also showed a significant difference by arm elevation in both groups (P = .04). Posterior tilting of the scapula gradually increased as the arm abduction angle increased, and this varied significantly between groups (P = .01). Shoulders with short malunion also showed a more internally rotated position than the contralateral, normal shoulders between 100° and the maximum abduction angle (P = .04). Our results suggest that clavicle shortening of >10% greatly affects scapular kinematics in vivo. Further studies will be needed to determine the clinical implications of short malunion of the clavicle. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

A New Piezoelectric Actuator Induces Bone Formation In Vivo: A Preliminary Study

PubMed Central

Reis, Joana; Frias, Clara; Canto e Castro, Carlos; Botelho, Maria Luísa; Marques, António Torres; Simões, José António Oliveira; Capela e Silva, Fernando; Potes, José

2012-01-01

This in vivo study presents the preliminary results of the use of a novel piezoelectric actuator for orthopedic application. The innovative use of the converse piezoelectric effect to mechanically stimulate bone was achieved with polyvinylidene fluoride actuators implanted in osteotomy cuts in sheep femur and tibia. The biological response around the osteotomies was assessed through histology and histomorphometry in nondecalcified sections and histochemistry and immunohistochemistry in decalcified sections, namely, through Masson's trichrome, and labeling of osteopontin, proliferating cell nuclear antigen, and tartrate-resistant acid phosphatase. After one-month implantation, total bone area and new bone area were significantly higher around actuators when compared to static controls. Bone deposition rate was also significantly higher in the mechanically stimulated areas. In these areas, osteopontin increased expression was observed. The present in vivo study suggests that piezoelectric materials and the converse piezoelectric effect may be used to effectively stimulate bone growth. PMID:22701304

Ex-vivo expansion of red blood cells: How real for transfusion in humans?

PubMed Central

Migliaccio, Anna Rita; Masselli, Elena; Varricchio, Lilian; Whitsett, Carolyn

2013-01-01

Blood transfusion is indispensable for modern medicine. In developed countries, the blood supply is adequate and safe but blood for alloimmunized patients is often unavailable. Concerns are increasing that donations may become inadequate in the future as the population ages prompting a search for alternative transfusion products. Improvements in culture conditions and proof-of-principle studies in animal models have suggested that ex-vivo expanded red cells may represent such a product. Compared to other cell therapies transfusion poses the unique challenge of requiring great cell doses (2.5 × 1012 cells vs 107 cells). Although production of such cell numbers is theoretically possible, current technologies generate red cells in numbers sufficient only for safety studies. It is conceived that by the time these studies will be completed, technical barriers to mass cell production will have been eliminated making transfusion with ex-vivo generated red cells a reality. PMID:22177597

Pulmonary toxicity of nanomaterials: a critical comparison of published in vitro assays and in vivo inhalation or instillation studies.

PubMed

Landsiedel, Robert; Sauer, Ursula G; Ma-Hock, Lan; Schnekenburger, Jürgen; Wiemann, Martin

2014-11-01

To date, guidance on how to incorporate in vitro assays into integrated approaches for testing and assessment of nanomaterials is unavailable. In addressing this shortage, this review compares data from in vitro studies to results from in vivo inhalation or intratracheal instillation studies. Globular nanomaterials (ion-shedding silver and zinc oxide, poorly soluble titanium dioxide and cerium dioxide, and partly soluble amorphous silicon dioxide) and nanomaterials with higher aspect ratios (multiwalled carbon nanotubes) were assessed focusing on the Organisation for Economic Co-Operation and Development (OECD) reference nanomaterials for these substances. If in vitro assays are performed with dosages that reflect effective in vivo dosages, the mechanisms of nanomaterial toxicity can be assessed. In early tiers of integrated approaches for testing and assessment, knowledge on mechanisms of toxicity serves to group nanomaterials thereby reducing the need for animal testing.

The practical approach to the evaluation of methods used to determine the disintegration time of orally disintegrating tablets (ODTs).

PubMed

Brniak, Witold; Jachowicz, Renata; Pelka, Przemyslaw

2015-09-01

Even that orodispersible tablets (ODTs) have been successfully used in therapy for more than 20 years, there is still no compendial method of their disintegration time evaluation other than the pharmacopoeial disintegration test conducted in 800-900 mL of distilled water. Therefore, several alternative tests more relevant to in vivo conditions were described by different researchers. The aim of this study was to compare these methods and correlate them with in vivo results. Six series of ODTs were prepared by direct compression. Their mechanical properties and disintegration times were measured with pharmacopoeial and alternative methods and compared with the in vivo results. The highest correlation with oral disintegration time was found in the case of own-construction apparatus with additional weight and the employment of the method proposed by Narazaki et al. The correlation coefficients were 0.9994 (p < 0.001), and 0.9907 (p < 0.001) respectively. The pharmacopoeial method correlated with the in vivo data much worse (r = 0.8925, p < 0.05). These results have shown that development of novel biorelevant methods of ODT's disintegration time determination is eligible and scientifically justified.

Design of asymmetric particles containing a charged interior and a neutral surface charge: comparative study on in vivo circulation of polyelectrolyte microgels.

PubMed

Chen, Kai; Xu, Jing; Luft, J Christopher; Tian, Shaomin; Raval, Jay S; DeSimone, Joseph M

2014-07-16

Lowering the modulus of hydrogel particles could enable them to bypass in vivo physical barriers that would otherwise filter particles with similar size but higher modulus. Incorporation of electrolyte moieties into the polymer network of hydrogel particles to increase the swelling ratio is a straightforward and quite efficient way to decrease the modulus. In addition, charged groups in hydrogel particles can also help secure cargoes. However, the distribution of charged groups on the surface of a particle can accelerate the clearance of particles. Herein, we developed a method to synthesize highly swollen microgels of precise size with near-neutral surface charge while retaining interior charged groups. A strategy was employed to enable a particle to be highly cross-linked with very small mesh size, and subsequently PEGylated to quench the exterior amines only without affecting the internal amines. Acidic degradation of the cross-linker allows for swelling of the particles to microgels with a desired size and deformability. The microgels fabricated demonstrated extended circulation in vivo compared to their counterparts with a charged surface, and could potentially be utilized in in vivo applications including as oxygen carriers or nucleic acid scavengers.

Improvement of the Pharmacokinetics and In Vivo Antibacterial Efficacy of a Novel Type IIa Topoisomerase Inhibitor by Formulation in Liposomes

PubMed Central

Newman, Joseph; Goteti, Kosalaram; Beaudoin, Marie-Eve; Harrison, Rane; Hopkins, Sussie; Agrawal, Nikunj; Rivin, Olga

2013-01-01

Several useful properties of liposome-based formulations of various existing antibacterial drugs have been reported. These properties include lower MICs, improved pharmacokinetics, lower toxicity, selective distribution to infected tissues, and enhanced in vivo efficacy. Here we report in vivo studies of a liposomal formulation of a member of a novel class of antibacterial type II topoisomerase inhibitors, others of which have progressed to early phases of clinical trials. The free (i.e., nonliposomal) compound has broad-spectrum MICs but suboptimal pharmacokinetics in rats and mice, characterized by a high volume of distribution and rapid clearance. The liposomal formulation of the compound had essentially unchanged MICs but greatly reduced volume of distribution and clearance in rats and mice. In an in vivo mouse model of Staphylococcus aureus infection of one thigh, the liposomal compound localized preferentially to the infected thigh, whereas the free compound showed no preference for the infected versus the uninfected thigh. Most importantly, the liposomal compound had enhanced efficacy at clearing the infection compared with the free compound. Delivery of this class of compounds as liposomal formulations may offer clinical advantages compared with free compounds. PMID:23877679

F4/80+ Host Macrophages Are a Barrier to Murine Embryonic Stem Cell-Derived Hematopoietic Progenitor Engraftment In Vivo.

PubMed

Thompson, Heather L; van Rooijen, Nico; McLelland, Bryce T; Manilay, Jennifer O

2016-01-01

Understanding how embryonic stem cells and their derivatives interact with the adult host immune system is critical to developing their therapeutic potential. Murine embryonic stem cell-derived hematopoietic progenitors (ESHPs) were generated via coculture with the bone marrow stromal cell line, OP9, and then transplanted into NOD.SCID.Common Gamma Chain (NSG) knockout mice, which lack B, T, and natural killer cells. Compared to control mice transplanted with adult lineage-negative bone marrow (Lin - BM) progenitors, ESHP-transplanted mice attained a low but significant level of donor hematopoietic chimerism. Based on our previous studies, we hypothesized that macrophages might contribute to the low engraftment of ESHPs in vivo . Enlarged spleens were observed in ESHP-transplanted mice and found to contain higher numbers of host F4/80 + macrophages compared to BM-transplanted controls. In vivo depletion of host macrophages using clodronate-loaded liposomes improved the ESHP-derived hematopoietic chimerism in the spleen but not in the BM. F4/80 + macrophages demonstrated a striking propensity to phagocytose ESHP targets in vitro . Taken together, these results suggest that macrophages are a barrier to both syngeneic and allogeneic ESHP engraftment in vivo .

[18F]tetrafluoroborate-PET/CT enables sensitive tumor and metastasis in vivo imaging in a sodium iodide symporter-expressing tumor model.

PubMed

Diocou, S; Volpe, A; Jauregui-Osoro, M; Boudjemeline, M; Chuamsaamarkkee, K; Man, F; Blower, P J; Ng, T; Mullen, G E D; Fruhwirth, G O

2017-04-19

Cancer cell metastasis is responsible for most cancer deaths. Non-invasive in vivo cancer cell tracking in spontaneously metastasizing tumor models still poses a challenge requiring highest sensitivity and excellent contrast. The goal of this study was to evaluate if the recently introduced PET radiotracer [ 18 F]tetrafluoroborate ([ 18 F]BF 4 - ) is useful for sensitive and specific metastasis detection in an orthotopic xenograft breast cancer model expressing the human sodium iodide symporter (NIS) as a reporter. In vivo imaging was complemented by ex vivo fluorescence microscopy and γ-counting of harvested tissues. Radionuclide imaging with [ 18 F]BF 4 - (PET/CT) was compared to the conventional tracer [ 123 I]iodide (sequential SPECT/CT). We found that [ 18 F]BF 4 - was superior due to better pharmacokinetics, i.e. faster tumor uptake and faster and more complete clearance from circulation. [ 18 F]BF 4 - -PET was also highly specific as in all detected tissues cancer cell presence was confirmed microscopically. Undetected comparable tissues were similarly found to be free of metastasis. Metastasis detection by routine metabolic imaging with [ 18 F]FDG-PET failed due to low standard uptake values and low contrast caused by adjacent metabolically active organs in this model. [ 18 F]BF 4 - -PET combined with NIS expressing disease models is particularly useful whenever preclinical in vivo cell tracking is of interest.

Preclinical evaluation of a novel cyanine dye for tumor imaging with in vivo photoacoustic imaging.

PubMed

Temma, Takashi; Onoe, Satoru; Kanazaki, Kengo; Ono, Masahiro; Saji, Hideo

2014-09-01

Photoacoustic imaging (PA imaging or PAI) has shown great promise in the detection and monitoring of cancer. Although nanocarrier-based contrast agents have been studied for use in PAI, small molecule contrast agents are required due to their ease of preparation, costeffectiveness, and low toxicity. Here, we evaluated the usefulness of a novel cyanine dye IC7-1-Bu as a PAI contrast agent without conjugated targeting moieties for in vivo tumor imaging in a mice model. Basic PA characteristics of IC7-1-Bu were compared with indocyanine green (ICG), a Food and Drug Administration approved dye, in an aqueous solution. We evaluated the tumor accumulation profile of IC7-1-Bu and ICG by in vivo fluorescence imaging. In vivo PAI was then performed with a photoacoustic tomography system 24 and 48 h after intravenous injection of IC7-1-Bu into tumor bearing mice. IC7-1-Bu showed about a 2.3-fold higher PA signal in aqueous solution compared with that of ICG. Unlike ICG, IC7-1-Bu showed high tumor fluorescence after intravenous injection. In vivo PAI provided a tumor to background PA signal ratio of approximately 2.5 after intravenous injection of IC7-1-Bu. These results indicate that IC7-1-Bu is a promising PAI contrast agent for cancer imaging without conjugation of targeting moieties.

Electrospun Nanofibrous P(DLLA-CL) Balloons as Calcium Phosphate Cement Filled Containers for Bone Repair: in Vitro and in Vivo Studies.

PubMed

Liu, Xunwei; Wei, Daixu; Zhong, Jian; Ma, Mengjia; Zhou, Juan; Peng, Xiangtao; Ye, Yong; Sun, Gang; He, Dannong

2015-08-26

The spinal surgeon community has expressed significant interest in applying calcium phosphate cement (CPC) for the treatment of vertebral compression fractures (VCFs) and minimizing its disadvantages, such as its water-induced collapsibility and poor mechanical properties, limiting its clinical use. In this work, novel biodegradable electrospun nanofibrous poly(d,l-lactic acid-ϵ-caprolactone) balloons (ENPBs) were prepared, and the separation, pressure, degradation, and new bone formation behaviors of the ENPBs when used as CPC-filled containers in vitro and in vivo were systematically analyzed and compared. CPC could be separated from surrounding bone tissues by ENPBs in vitro and in vivo. ENPB-CPCs (ENPBs serving as CPC-filled containers) exerted pressure on the surrounding bone microenvironment, which was enough to crush trabecular bone. Compared with the CPC implantation, ENPB-CPCs delayed the degradation of CPC (i.e., its water-induced collapsilibity). Finally, possible mechanisms behind the in vivo effects caused by ENPB-CPCs implanted into rabbit thighbones and pig vertebrae were proposed. This work suggests that ENPBs can be potentially applied as CPC-filled containers in vivo and provides an experimental basis for the clinical application of ENPBs for the treatment of VCFs. In addition, this work will be of benefit to the development of polymer-based medical implants in the future.

In Vitro/In Vivo Evaluation of Dexamethasone--PAMAM Dendrimer Complexes for Retinal Drug Delivery.

PubMed

Yavuz, Burçin; Pehlivan, Sibel Bozdağ; Vural, İmran; Ünlü, Nurşen

2015-11-01

Current treatment options for diabetic retinopathy (DR) have side effects because of invasive application and topical application does not generally result in therapeutic levels in the target tissue. Therefore, improving the drug delivery to retina, following topical administration, might be a solution to DR treatment problems. The purpose of this study was to investigate the complexation effects of poly(amidoamine) (PAMAM) dendrimers on ocular absorption of dexamethasone (DEX). Using different PAMAM generations, complex formulations were prepared and characterized. Formulations were evaluated in terms of cytotoxicity and cell permeability, as well as ex vivo transport across ocular tissues. The ocular pharmacokinetic properties of DEX formulations were studied in Sprague-Dawley rats following topical and subconjunctival applications, to evaluate the effect of PAMAM on retinal delivery of DEX. Methyl-thiazol-tetrazolium (MTT) assay indicated that all groups resulted in cell viability comparable to DEX solution (87.5%), with the cell viability being the lowest for G3 complex at 73.5%. Transport study results showed that dendrimer complexation increases DEX transport across both cornea and sclera tissues. The results of in vivo studies were also indicated that especially anionic DEX-PAMAM complex formulations have reached higher DEX concentrations in ocular tissues compared with plain DEX suspension. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

Terbinafine hydrochloride nanovesicular gel: In vitro characterization, ex vivo permeation and clinical investigation.

PubMed

AbdelSamie, Sara M; Kamel, Amany O; Sammour, Omaima A; Ibrahim, Shady M

2016-06-10

In this work, nanovesicular chitosan gels were prepared for dermal delivery of terbinafine hydrochloride (TBN HCl). Ethosomes and vesicles containing different types of penetration enhancers (PEs) viz. Terpenes (cineole and limonene), labrasol and transcutol were developed. The prepared vesicles were evaluated for physical characteristics as well as skin interaction. The selected vesicles were incorporated into chitosan gel. An in vivo animal study was done on rat induced superficial Candida infection model. Moreover, randomized double blind clinical study was done on patients to compare the effect of the selected nanovesicular gel against the market product. Results showed the formation of nearly spherical, mostly deformable vesicular systems with size range of 95.5-530nm, zeta potential range of -0.1 to 15mV and entrapment efficiency range of 20-96.7%. Penetration enhancer vesicles (PEVs) prepared with 4% limonene (ELI4) showed the highest percent of drug deposition in the skin (53%) and the highest local accumulation efficiency value (35.3). In vivo animal study showed that the lowest fungal burden produced with ELI4 chitosan gel. Clinical studies showed cure rate of 86% within 7days treatment in case of limonene nanovesicular gel compared to 20% for market product (Lamisil® cream). Copyright © 2016 Elsevier B.V. All rights reserved.

In Vitro and In Vivo Evaluation of a Novel Ferrocyanide Functionalized Nanopourous Silica Decorporation Agent for Cesium (Cs) in Rats

PubMed Central

Timchalk, Charles; Creim, Jeffrey A; Sukwarotwat, Vichaya; Wiacek, Robert; Addleman, R Shane; Fryxell, Glen E; Yantasee, Wassana

2009-01-01

Novel decorporation agents are being developed to protect against radiological terrorist attacks. These sorbents, known as the self-assembled monolayer on mesoporous supports (SAMMS™), are hybrid materials where differing organic moieties are grafted onto mesoporous silica (SiO2). In vitro experiments focused on the evaluation, and optimization of SAMMS for capturing radiocesium (137Cs); therefore based on these studies, a ferrocyanide copper (FC-Cu-EDA)-SAMMS was advanced for in vivo evaluation. In vivo experiments were conducted comparing the performance of the SAMMS vs. insoluble Prussian blue. Groups of jugular cannulated rats (4/treatment) were evaluated. Animals in group I were administered 137Cs chloride (~40 μg/kg) by intravenous (iv) injection or oral gavage; Group II animals were administered pre-bound 137Cs- SAMMS or sequential 137Cs chloride + SAMMS (~61 ng/kg) by oral gavage; and Group III was orally administered 137Cs chloride (~61 ng/kg) followed by either 0.1 g of SAMMS or Prussian blue. Following dosing, the rats were maintained in metabolism cages for 72 hour and blood, urine and fecal samples were collected for 137Cs analysis (gamma counting). Rats were then humanely euthanized, and selected tissues analyzed. Orally administered 137Cs chloride was rapidly and well absorbed (~100% relative to iv dose), and the pharmacokinetics (blood, urine, feces & tissues) were very comparable to the iv dose group. For both exposures the urine and feces accounted for 20 and 3% of the dose, respectively. The prebound 137Cs-SAMMS was retained primarily within the feces (72% of the dose), with ~1.4% detected in the urine, suggesting that the 137Cs remained tightly bound to SAMMS. SAMMS & Prussian blue both effectively captured available 137Cs in the gut with feces accounting for 80–88% of the administered dose, while less than 2% was detected in the urine. This study suggests that the functionalized SAMMS outperforms Prussian blue in vitro at low pH, but demonstrates comparable in vivo sequestration efficacy at low exposure concentrations. The comparable response may be the result of the low 137Cs chloride dose and high sorbent dosage that was utilized. Future studies are planned to optimize SAMMS in vivo performance over a broader range of doses and conditions. PMID:20699707

In Vitro and In Vivo Evaluation of a Novel Ferrocyanide Functionalized Nanopourous Silica Decorporation Agent for Cesium in Rats

DOE Office of Scientific and Technical Information (OSTI.GOV)

Timchalk, Charles; Creim, Jeffrey A.; Sukwarotwat, Vichaya

2010-09-01

Novel decorporation agents are being developed to protect against radiological terrorist attacks. These sorbents, known as the self-assembled monolayer on mesoporous supports (SAMMS™), are hybrid materials where differing organic moieties are grafted onto mesoporous silica (SiO2). In vitro experiments focused on the evaluation, and optimization of SAMMS for capturing radiocesium (137Cs); based on these studies, a ferrocyanide copper (FC-Cu-EDA)-SAMMS was advanced for in vivo evaluation. In vivo experiments were conducted comparing the performance of the SAMMS vs. insoluble Prussian blue. Groups of jugular cannulated rats (4/treatment) were evaluated. Group I was administered 137Cs (~40 μgeq/kg) by intravenous (iv) injection andmore » oral gavage; Group II was administered pre-bound 137Cs-SAMMS and sequential 137Cs + SAMMS (~61 ngeq/kg) by oral gavage; and Group III evaluated orally administered 137Cs (~0.06 μgeq/kg) followed by 0.1 g of either SAMMS or Prussian blue. Following dosing the rats were maintained in metabolism cages for 72 hour and blood, urine and fecal samples were collected for 137Cs analysis (gamma counting). Rats were then humanely euthanized, and selected tissues analyzed. Orally administered 137Cs was rapidly and well absorbed (~100% relative to iv dose), and the pharmacokinetics (blood, urine, feces & tissues) were very comparable to the iv dose group. For both exposures the urine and feces accounted for 20 and 3% of the dose, respectively. The prebound 137Cs-SAMMS was retained primarily within the feces (72% of the dose), with ~1.4% detected in the urine, suggesting that the 137Cs remained tightly bound to SAMMS. SAMMS & Prussian blue both effectively captured available 137Cs in the gut with feces accounting for 80-88% of the administered dose, while less than 2% was detected in the urine. This study suggests that the functionalized SAMMS out performs Prussian blue in vitro at low pH, but demonstrates comparable in vivo sequestration efficacy at low exposure concentrations. The comparable response may be the result of the low 137Cs dose and high sorbent dosage that was utilized. Future studies are planned to optimize SAMMS in vivo performance over a broader range of doses and conditions.« less

Functional Probiotic Characterization and In Vivo Cholesterol-Lowering Activity of Lactobacillus helveticus Isolated from Fermented Cow Milk.

PubMed

Damodharan, Karthiyaini; Palaniyandi, Sasikumar Arunachalam; Yang, Seung Hwan; Suh, Joo-Won

2016-10-28

We characterized the probiotic properties of Lactobacillus helveticus strains KII13 and KHI1 isolated from fermented cow milk by in vitro and in vivo studies. The strains exhibited tolerance to simulated orogastrointestinal condition, adherence to Caco-2 cells, and antimicrobial activity. Both L. helveticus strains produced bioactive tripeptides, isoleucylprolyl-proline and valyl-prolyl-proline, during fermentation of milk. KII13 showed higher in vitro cholesterol-lowering activity (47%) compared with KHI1 (28%) and L. helveticus ATCC 15009 (22%), and hence, it was selected for in vivo study of cholesterol-lowering activity in atherogenic diet-fed hypercholesterolemic mice. For the study, mice were divided into four groups ( viz ., normal diet control group, atherogenic diet control group (HCD), KII13- atherogenic diet group (HCD-KII13), and Lactobacillus acidophilus ATCC 43121-atherogenic diet group (HCD- L.ac ) as positive control). The serum total cholesterol level was significantly decreased by 8.6% and 7.78% in the HCD-KII13 and HCD- L.ac groups ( p < 0.05), respectively, compared with the HCD group. Low-density lipoprotein cholesterol levels in both HCD-KII13 and HCD- L.ac groups were decreased by 13% and 11%, respectively, compared with the HCD group (both, p < 0.05). Analysis of cholesterol metabolism-related gene expression in mice liver showed increased expression of LDLR and SREBF2 genes in mice fed with KII13. By comparing all the results, we conclude that L. helveticus KII13 could be used as a potential probiotic strain to produce antihypertensive peptides and reduce serum cholesterol.

Focused ultrasound-facilitated brain drug delivery using optimized nanodroplets: vaporization efficiency dictates large molecular delivery

NASA Astrophysics Data System (ADS)

Wu, Shih-Ying; Fix, Samantha M.; Arena, Christopher B.; Chen, Cherry C.; Zheng, Wenlan; Olumolade, Oluyemi O.; Papadopoulou, Virginie; Novell, Anthony; Dayton, Paul A.; Konofagou, Elisa E.

2018-02-01

Focused ultrasound with nanodroplets could facilitate localized drug delivery after vaporization with potentially improved in vivo stability, drug payload, and minimal interference outside of the focal zone compared with microbubbles. While the feasibility of blood-brain barrier (BBB) opening using nanodroplets has been previously reported, characterization of the associated delivery has not been achieved. It was hypothesized that the outcome of drug delivery was associated with the droplet’s sensitivity to acoustic energy, and can be modulated with the boiling point of the liquid core. Therefore, in this study, octafluoropropane (OFP) and decafluorobutane (DFB) nanodroplets were used both in vitro for assessing their relative vaporization efficiency with high-speed microscopy, and in vivo for delivering molecules with a size relevant to proteins (40 kDa dextran) to the murine brain. It was found that at low pressures (300-450 kPa), OFP droplets vaporized into a greater number of microbubbles compared to DFB droplets at higher pressures (750-900 kPa) in the in vitro study. In the in vivo study, successful delivery was achieved with OFP droplets at 300 kPa and 450 kPa without evidence of cavitation damage using ¼ dosage, compared to DFB droplets at 900 kPa where histology indicated tissue damage due to inertial cavitation. In conclusion, the vaporization efficiency of nanodroplets positively impacted the amount of molecules delivered to the brain. The OFP droplets due to the higher vaporization efficiency served as better acoustic agents to deliver large molecules efficiently to the brain compared with the DFB droplets.

Stability of knee ligament complex of Thiel-embalmed cadaver compared to in vivo knee.

PubMed

Völlner, Florian; Pilsl, Ulrike; Craiovan, Benjamin; Zeman, Florian; Schneider, Michael; Wörner, Michael; Grifka, Joachim; Weber, Markus

2017-07-01

The first biomechanical evaluation of new implants is usually carried out with cadavers. Fixation of Thiel-embalmed cadavers is supposed to preserve the histological structure, colour and consistency of the tissue and has a low risk of infection and toxicity. However, the biomechanical properties of Thiel-fixated tissue are still unknown. The aim of this study was to quantify the effect of the Thiel-embalming method on the elastic properties of the ligament complex of the knee compared to in vivo knees during total knee arthroplasty. The results of biomechanical tensile tests with 10 Thiel-embalmed knees were compared with the findings of 10 patients who underwent total knee arthroplasty with a standardised knee balancer at our department. We reconstructed the force-elongation curves of the medial and lateral ligament complex and calculated the stiffness in direct correlation with overall soft tissue stability in full extension and in 90° of flexion. All curves consisted of a non-linear part at the beginning and a linear part from about 80N onwards. In full extension, median stiffness in the cadavers was 26.6N/mm for the medial compartment and 31.6N/mm for the lateral compartment. The values for in vivo were 25.7N/mm for the medial compartment and 25.3N/mm for the lateral compartment (p=0.684 for the medial compartment and p=0.247 for the lateral compartment). In 90° of flexion, median stiffness in the cadaver group was 24.7N/mm for the medial compartment and 22.2N/mm for the lateral compartment. In vivo, median stiffness was 30.3N/mm for the medial compartment and 29.2N/mm for the lateral compartment (p=0.009 for the medial compartment and p=0.143 for the lateral compartment). Stiffness of the medial and lateral ligament complex in the knee was comparable between Thiel-embalmed cadavers and in vivo patients during total knee arthroplasty. Thiel fixation seems to preserve the soft tissue properties similar to those in vivo. Copyright © 2017 Elsevier Ltd. All rights reserved.

High-Frequency Ultrasonic Imaging of the Anterior Segment Using an Annular Array Transducer

PubMed Central

Silverman, Ronald H.; Ketterling, Jeffrey A.; Coleman, D. Jackson

2006-01-01

Objective Very-high-frequency (>35 MHz) ultrasound (VHFU) allows imaging of anterior segment structures of the eye with a resolution of less than 40-μm. The low focal ratio of VHFU transducers, however, results in a depth-of-field (DOF) of less than 1-mm. Our aim was to develop a high-frequency annular array transducer for ocular imaging with improved DOF, sensitivity and resolution compared to conventional transducers. Design Experimental Study Participants Cadaver eyes, ex vivo cow eyes, in vivo rabbit eyes. Methods A spherically curved annular array ultrasound transducer was fabricated. The array consisted of five concentric rings of equal area, had an overall aperture of 6 mm and a geometric focus of 12 mm. The nominal center frequency of all array elements was 40 MHz. An experimental system was designed in which a single array element was pulsed and echo data recorded from all elements. By sequentially pulsing each element, echo data were acquired for all 25 transmit/receive annuli combinations. The echo data were then synthetically focused and composite images produced. Transducer operation was tested by scanning a test object consisting of a series of 25-μm diameter wires spaced at increasing range from the transducer. Imaging capabilities of the annular array were demonstrated in ex vivo bovine, in vivo rabbit and human cadaver eyes. Main Outcome Measures Depth of field, resolution and sensitivity. Results The wire scans verified the operation of the array and demonstrated a 6.0 mm DOF compared to the 1.0 mm DOF of a conventional single-element transducer of comparable frequency, aperture and focal length. B-mode images of ex vivo bovine, in vivo rabbit and cadaver eyes showed that while the single-element transducer had high sensitivity and resolution within 1–2 mm of its focus, the array with synthetic focusing maintained this quality over a 6 mm DOF. Conclusion An annular array for high-resolution ocular imaging has been demonstrated. This technology offers improved depth-of-field, sensitivity and lateral resolution compared to single-element fixed focus transducers currently used for VHFU imaging of the eye. PMID:17141314

High-frequency ultrasonic imaging of the anterior segment using an annular array transducer.

PubMed

Silverman, Ronald H; Ketterling, Jeffrey A; Coleman, D Jackson

2007-04-01

Very high-frequency ultrasound (VHFU; >35 megahertz [MHz]) allows imaging of anterior segment structures of the eye with a resolution of less than 40 microm. The low focal ratio of VHFU transducers, however, results in a depth of field (DOF) of less than 1 mm. The aim was to develop a high-frequency annular array transducer for ocular imaging with improved DOF, sensitivity, and resolution compared with conventional transducers. Experimental study. Cadaver eyes, ex vivo cow eyes, in vivo rabbit eyes. A spherically curved annular array ultrasound transducer was fabricated. The array consisted of 5 concentric rings of equal area, had an overall aperture of 6 mm, and a geometric focus of 12 mm. The nominal center frequency of all array elements was 40 MHz. An experimental system was designed in which a single array element was pulsed and echo data were recorded from all elements. By sequentially pulsing each element, echo data were acquired for all 25 transmit-and-receive annuli combinations. The echo data then were focused synthetically and composite images were produced. Transducer operation was tested by scanning a test object consisting of a series of 25-microm diameter wires spaced at increasing range from the transducer. Imaging capabilities of the annular array were demonstrated in ex vivo bovine, in vivo rabbit, and human cadaver eyes. Depth of field, resolution, and sensitivity. The wire scans verified the operation of the array and demonstrated a 6.0-mm DOF, compared with the 1.0-mm DOF of a conventional single-element transducer of comparable frequency, aperture, and focal length. B-mode images of ex vivo bovine, in vivo rabbit, and cadaver eyes showed that although the single-element transducer had high sensitivity and resolution within 1 to 2 mm of its focus, the array with synthetic focusing maintained this quality over a 6-mm DOF. An annular array for high-resolution ocular imaging has been demonstrated. This technology offers improved DOF, sensitivity, and lateral resolution compared with single-element fixed focus transducers currently used for VHFU imaging of the eye.

Strategies for Determining Correct Cytochrome P450 Contributions in Hepatic Clearance Predictions: In Vitro-In Vivo Extrapolation as Modelling Approach and Tramadol as Proof-of Concept Compound.

PubMed

T'jollyn, Huybrecht; Snoeys, Jan; Van Bocxlaer, Jan; De Bock, Lies; Annaert, Pieter; Van Peer, Achiel; Allegaert, Karel; Mannens, Geert; Vermeulen, An; Boussery, Koen

2017-06-01

Although the measurement of cytochrome P450 (CYP) contributions in metabolism assays is straightforward, determination of actual in vivo contributions might be challenging. How representative are in vitro for in vivo CYP contributions? This article proposes an improved strategy for the determination of in vivo CYP enzyme-specific metabolic contributions, based on in vitro data, using an in vitro-in vivo extrapolation (IVIVE) approach. Approaches are exemplified using tramadol as model compound, and CYP2D6 and CYP3A4 as involved enzymes. Metabolism data for tramadol and for the probe substrates midazolam (CYP3A4) and dextromethorphan (CYP2D6) were gathered in human liver microsomes (HLM) and recombinant human enzyme systems (rhCYP). From these probe substrates, an activity-adjustment factor (AAF) was calculated per CYP enzyme, for the determination of correct hepatic clearance contributions. As a reference, tramadol CYP contributions were scaled-back from in vivo data (retrograde approach) and were compared with the ones derived in vitro. In this view, the AAF is an enzyme-specific factor, calculated from reference probe activity measurements in vitro and in vivo, that allows appropriate scaling of a test drug's in vitro activity to the 'healthy volunteer' population level. Calculation of an AAF, thus accounts for any 'experimental' or 'batch-specific' activity difference between in vitro HLM and in vivo derived activity. In this specific HLM batch, for CYP3A4 and CYP2D6, an AAF of 0.91 and 1.97 was calculated, respectively. This implies that, in this batch, the in vitro CYP3A4 activity is 1.10-fold higher and the CYP2D6 activity 1.97-fold lower, compared to in vivo derived CYP activities. This study shows that, in cases where the HLM pool does not represent the typical mean population CYP activities, AAF correction of in vitro metabolism data, optimizes CYP contributions in the prediction of hepatic clearance. Therefore, in vitro parameters for any test compound, obtained in a particular batch, should be corrected with the AAF for the respective enzymes. In the current study, especially the CYP2D6 contribution was found, to better reflect the average in vivo situation. It is recommended that this novel approach is further evaluated using a broader range of compounds.

The Visi-Chroma VC-100: a new imaging colorimeter for dermatocosmetic research.

PubMed

Barel, A O; Clarys, P; Alewaeters, K; Duez, C; Hubinon, J L; Mommaerts, M

2001-02-01

It was the aim of this study to carry out a comparative evaluation in vitro on standardized color charts and in vivo on healthy subjects using the Visi-Chroma VC-100, a new imaging tristimulus colorimeter and the Minolta Chromameter CR-200 as a reference instrument. The Visi-Chroma combines tristimulus color analysis with full color visualization of the skin area measured. The technical performances of both instruments were compared with the purpose of validating the use of this new imaging colorimeter in dermatocosmetic research. In vitro L*a*b* color parameters were taken with both instruments on standardized color charts (Macbeth and RAL charts) in order to evaluate accuracy, sensitivity range and repeatability. These measurements were completed by in vivo studies on different sites of human skin and studies of color changes induced by topical chemical agents on forearm skin. The accuracy, sensitivity range and repeatability of measurements of selected distances and surfaces in the measuring zone considered and specific color determinations of specific skin zones were also determined. The technical performance of this imaging colorimeter was rather good, with low coefficients of variation for repeatability of in vitro and vivo color measurements. High positive correlations were established in vitro and in vivo over a wide range of color measurements. The imaging colorimeter was able to measure the L*a*b* color parameters of specific chosen parts of the skin area considered and to measure accurately selected distances and surfaces in the same skin site considered. These comparative measurements show that both instruments have very similar technical performances and that high levels of correlation were obtained in vitro and in vivo using the L*a*b* color parameters. In addition, the Visi-Chroma presents the following improvements: 1) direct visualization and recording of the skin area considered with concomitant color measurements; 2) determination of the specific color parameters of skin areas chosen in the total measuring area; and 3) accurate determination of selected distances and surfaces in the same skin areas chosen.

Solid lipid nanoparticles bearing oxybenzone: in-vitro and in-vivo evaluation.

PubMed

Gulbake, Arvind; Jain, Aviral; Khare, Piush; Jain, Sanjay K

2010-05-01

In the present project, Solid Lipid Nanoparticles (SLNs) bearing oxybenzone were prepared by ethanol injection method to improve its effectiveness as sunscreen. SLNs were characterized for particle size,polydispersity index, zeta potential and surface morphology. The optimized SLNs bearing oxybenzone were incorporated into water-removable cream base and compared with SLNs unloaded water-removable cream base for in vitro and in vivo parameters. Cream base formulation containing SLNs (Csd) with 5% oxybenzone showed slow drug release and better sun protecting factor (more than 25) compared to cream base containing 5% oxybenzone. Confocal Laser Scanning Microscopy was used to visualize the distribution of developed formulations in skin. CLSM indicated prolonged retention of SLNs in the stratum corneum as compared to plain cream base. These studies revealed that the cream base bearing SLNs exhibited good skin retention as well as enhanced sun protection effect compared to cream base.

Solar-simulating irradiation of the skin of human subjects in vivo produces Langerhans cell responses distinct from irradiation ex vivo and in vitro.

PubMed

Laihia, J K; Jansen, C T

2000-08-01

It has been postulated that Langerhans cells (LC) provide tolerogenic signals in the local impairment of cutaneous immune functions and antigen-specific tolerance induced by UV radiation. Studies in vitro and ex vivo have indicated that UV radiation may down-regulate the expression of costimulatory molecules on LC, leading to reduced antigen-presenting function. In contrast, we recently observed an up-regulatory stage in the number of human epidermal LC with induced expression of B7 costimulatory molecules 12-24 h after solar-simulating UV radiation (SSR) in vivo. To examine the apparent discrepancy between the observed human LC responses in vitro, ex vivo and in vivo, we compared the three protocols in a parallel fashion. The intact skin as well as skin explants and epidermal cell suspensions from the same individuals were irradiated with a single erythematogenic dose of SSR. The expression of cell surface markers in the epidermal cells was analysed with flow cytometry 24 h later. The number of CD1a+/HLA-DR+ LC increased post-SSR in vivo by a factor of 2.8+/-0.4, whereas in irradiated skin explants ex vivo or in cell suspensions in vitro, reduced numbers were seen. HLA-DR expression intensities were found to have increased on DR+ and CD1a+/DR+ cells in vivo. Similarly, SSR induced B7-2 (CD86) expression in CD1a+ cells significantly in vivo (P=0.031) but reduced the expression ex vivo or in vitro. We conclude that the early up-regulatory stage of human LC number and membrane markers, recorded at 24 h after a single exposure to SSR, is exclusively an in vivo phenomenon.

PREPARATION, IN VITRO AND IN VIVO CHARACTERIZATION OF HYDROPHOBIC PATCHES OF A HIGHLY WATER SOLUBLE DRUG FOR PROLONGED PLASMA HALF LIFE: EFFECT OF PERMEATION ENHANCERS.

PubMed

Yaqoob, Ayesha; Ahmad, Mahmood; Mahmood, Asif; Sarfraz, Rai Muhammad

2016-11-01

Aim of present study was to develop metoprolol matrix patches using different enhancers. Combination of two hydrophobic polymers, ethyl cellulose and eudragit RL 100 (8 : 2) were used for preparation of unilaminated matrix patch. 10% w/w of isopropyl myristate (IPM), dimethyl sulfoxide (DMSO), span (20 (S20), Tween 20 (T20) and eucalyptus oil as enhancers and 40% of dibutyl phthalate as plasticizer were used. Prepared patches were evaluated for physical appearance, weight uniformity and thickness. FTIR studies were performed to assess compatibility among ingredients and developed formulation. Dissolution and permeation studies were performed to compare effects of enhancers. Surface morphology after release was examined by scanning electron microscopy. Selected formulation was subjected to in vivo studies by randomized crossover design in rabbits (n = 6) for pharmacokinetic comparison with oral solution administration. Physical evaluation revealed that translucent, flexible, non brittle patches of uniform weight and thickness were prepared. Release from patches followed Higuchi model. Mechanism of release was Fickian. Formulation containing IPM showed that release was by anomalous transport. Highest permeation flux was observed for formulation containing IPM with 2-fold enhancement in permeation. Permeation flux for patches was in order of formulation with no enhancer > IPM > T20 > S20 > DMSO = eucalyptus oil. Plasma concentration from in vivo studies exhibited sustained plasma levels of metoprolol after transdermal patch application in comparison to oral solution administration. Pharmacokinetic analysis of in vivo data elucidated that half life was increased 8 times when compared to oral administration, due to controlled release of drug for longer period of time. These findings suggested that hydrophobic transdermal patches of highly water soluble drug metoprolol were successfully prepared with 10% of IPM for sustained systemic delivery for prolonged half life.

Comparison of glucose metabolism in in vivo- and in vitro-matured tammar wallaby oocytes and its relationship to developmental potential following intracytoplasmic sperm injection.

PubMed

Magarey, Genevieve M; Mate, Karen E

2004-01-01

Although marsupial oocytes undergo nuclear maturation in vitro, there is, at present, no indication of their developmental potential, largely owing to the lack of in vitro fertilisation and related technologies for marsupials. Glucose metabolism has proven a useful indicator of oocyte cytoplasmic maturation and developmental potential in several eutherian species. Therefore, the aims of the present study were to compare: (1) the rates of glycolysis and glucose oxidation in immature, in vitro-matured and in vivo-matured tammar wallaby oocytes; and (2) the metabolic rate of individual oocytes with their ability to form pronuclei after intracytoplasmic sperm injection. The rates of glycolysis measured in immature (2.18 pmol oocyte(-1) h(-1)), in vitro- matured (0.93 pmol oocyte(-1) h(-1)) and in vivo-matured tammar wallaby oocytes (0.54 pmol oocyte(-1) h(-1)) were within a similar range to values obtained in eutherian species. However, unlike the trend observed in eutherian oocytes, the glycolytic rate was significantly higher in immature oocytes compared with either in vivo- or in vitro-matured oocytes (P < 0.001) and significantly higher in in vitro-matured oocytes compared with in vivo-matured oocytes (P < 0.001). No relationship was identified between glucose metabolism and the developmental capacity of oocytes after intracytoplasmic sperm injection when assessed after 17-19 h. Oocytes that became fertilised (two pronuclei) or activated (one or more pronucleus) were not distinguished from others by their metabolic rates. Longer culture after intracytoplasmic sperm injection (e.g. blastocyst stage) may show oocyte glucose metabolism to be predictive of developmental potential; however, culture to the single-cell stage did not reveal any significant differences in normally developing embryos.

ANTIVIRAL ACTIVITY OF DIANTHUS SUPERBUSN L. AGAINST HEPATITIS B VIRUS IN VITRO AND IN VIVO.

PubMed

Li, Wei-Guo; Wang, He-Qun

2016-01-01

Hepatitis is a viral infection of hepatitis B virus (HBV). Limitations of drug used in the management of it opens the interest related to alternative medicine. The given study deals with the antiviral activity of Dianthus superbusn L. (DSL) against HBV in vitro & in vivo . In vitro study liver cell line HepG2.2.15 was used by transinfected it with HBV. Cytotoxicity stduy was performed by using different concentrations of DSL such as 50, 100, 200, 500 & 1000 μg/ml. Anti HBV activity of DSL was estimated by assesing the concentration of HBsAg and HbeAg in cell culture medium by using ELISA. Whereas in vivo study was performed on ducklings and antiviral activity of DSL (100, 200, 400 mg/kg) was confirmed by estimating the serum concentration of HBV DNA and histopathology study of hepatocytes in HBV infected ducklings. Result of the study suggested that >500 μg/ml concentration of hydroalcoholic extract of DSL was found tobe cytotoxic. It was also observed that DSL significantly ( p <0.05) reduces the concentration of antigenes in cell culture media as per the concentration and days of treatment dependent. Moreover in vivo study confirms the anti viral activity of DSL (200 & 400 mg/kg) as it significantly ( p <0.05) decreases the serum concenetration of HBV DNA in HBV infected dukling compared to control group. Histopathology study was also reveals the hepatprotective effect of DSL in HBV infected ducklings. The given study concludes the antiviral activity DSL against HBV by in vitro and in vivo models.

Comparative study on the biodegradation and biocompatibility of silicate bioceramic coatings on biodegradable magnesium alloy as biodegradable biomaterial

NASA Astrophysics Data System (ADS)

Razavi, M.; Fathi, M. H.; Savabi, O.; Razavi, S. M.; Hashemibeni, B.; Yazdimamaghani, M.; Vashaee, D.; Tayebi, L.

2014-03-01

Many clinical cases as well as in vivo and in vitro assessments have demonstrated that magnesium alloys possess good biocompatibility. Unfortunately, magnesium and its alloys degrade too quickly in physiological media. In order to improve the biodegradation resistance and biocompatibility of a biodegradable magnesium alloy, we have prepared three types of coating include diopside (CaMgSi2O6), akermanite (Ca2MgSi2O6) and bredigite (Ca7MgSi4O16) coating on AZ91 magnesium alloy through a micro-arc oxidation (MAO) and electrophoretic deposition (EPD) method. In this research, the biodegradation and biocompatibility behavior of samples were evaluated in vitro and in vivo. The in vitro analysis was performed by cytocompatibility and MTT-assay and the in vivo test was conducted on the implantation of samples in the greater trochanter of adult rabbits. The results showed that diopside coating has the best bone regeneration and bredigite has the best biodegradation resistance compared to others.

Evaluation of sub-microsecond recovery resonators for In Vivo Electron Paramagnetic Resonance Imaging

PubMed Central

F, Hyodo; S, Subramanian; N, Devasahayam; R, Murugesan; K, Matsumoto; JB, Mitchell; MC, Krishna

2008-01-01

Time-domain (TD) electron paramagnetic resonance (EPR) imaging at 300 MHz for in vivo applications requires resonators with recovery times less than 1 microsecond after pulsed excitation to reliably capture the rapidly decaying free induction decay (FID). In this study, we tested the suitability of the Litz foil coil resonator (LCR), commonly used in MRI, for in vivo EPR/EPRI applications in the TD mode and compared with parallel coil resonator (PCR). In TD mode, the sensitivity of LCR was lower than that of the PCR. However, in continuous wave (CW) mode, the LCR showed better sensitivity. The RF homogeneity was similar in both the resonators. The axis of the RF magnetic field is transverse to the cylindrical axis of the LCR, making the resonator and the magnet co-axial. Therefore, the loading of animals, and placing of the anesthesia nose cone and temperature monitors was more convenient in the LCR compared to the PCR whose axis is perpendicular to the magnet axis. PMID:18042414

Nano-palladium is a cellular catalyst for in vivo chemistry

NASA Astrophysics Data System (ADS)

Miller, Miles A.; Askevold, Bjorn; Mikula, Hannes; Kohler, Rainer H.; Pirovich, David; Weissleder, Ralph

2017-07-01

Palladium catalysts have been widely adopted for organic synthesis and diverse industrial applications given their efficacy and safety, yet their biological in vivo use has been limited to date. Here we show that nanoencapsulated palladium is an effective means to target and treat disease through in vivo catalysis. Palladium nanoparticles (Pd-NPs) were created by screening different Pd compounds and then encapsulating bis[tri(2-furyl)phosphine]palladium(II) dichloride in a biocompatible poly(lactic-co-glycolic acid)-b-polyethyleneglycol platform. Using mouse models of cancer, the NPs efficiently accumulated in tumours, where the Pd-NP activated different model prodrugs. Longitudinal studies confirmed that prodrug activation by Pd-NP inhibits tumour growth, extends survival in tumour-bearing mice and mitigates toxicity compared to standard doxorubicin formulations. Thus, here we demonstrate safe and efficacious in vivo catalytic activity of a Pd compound in mammals.

In vivo demonstration of surgical task assistance using miniature robots.

PubMed

Hawks, Jeff A; Kunowski, Jacob; Platt, Stephen R

2012-10-01

Laparoscopy is beneficial to patients as measured by less painful recovery and an earlier return to functional health compared to conventional open surgery. However, laparoscopy requires the manipulation of long, slender tools from outside the patient's body. As a result, laparoscopy generally benefits only patients undergoing relatively simple procedures. An innovative approach to laparoscopy uses miniature in vivo robots that fit entirely inside the abdominal cavity. Our previous work demonstrated that a mobile, wireless robot platform can be successfully operated inside the abdominal cavity with different payloads (biopsy, camera, and physiological sensors). We hope that these robots are a step toward reducing the invasiveness of laparoscopy. The current study presents design details and results of laboratory and in vivo demonstrations of several new payload designs (clamping, cautery, and liquid delivery). Laboratory and in vivo cooperation demonstrations between multiple robots are also presented.

Electrochemical properties of titanium nitride nerve stimulation electrodes: an in vitro and in vivo study

PubMed Central

Meijs, Suzan; Fjorback, Morten; Jensen, Carina; Sørensen, Søren; Rechendorff, Kristian; Rijkhoff, Nico J. M.

2015-01-01

The in vivo electrochemical behavior of titanium nitride (TiN) nerve stimulation electrodes was compared to their in vitro behavior for a period of 90 days. Ten electrodes were implanted in two Göttingen minipigs. Four of these were used for electrical stimulation and electrochemical measurements. Five electrodes were kept in Ringer's solution at 37.5°C, of which four were used for electrical stimulation and electrochemical measurements. The voltage transients measured in vivo were 13 times greater than in vitro at implantation and they continued to increase with time. The electrochemical properties in vivo and the tissue resistance (Rtissue) followed a similar trend with time. There was no consistent significant difference between the electrochemical properties of the in vivo and in vitro electrodes after the implanted period. The differences between the in vivo and in vitro electrodes during the implanted period show that the evaluation of electrochemical performance of implantable stimulation electrodes cannot be substituted with in vitro measurements. After the implanted period, however, the performance of the in vivo and in vitro electrodes in saline was similar. In addition, the changes observed over time during the post-implantation period regarding the electrochemical properties of the in vivo electrodes and Rtissue were similar, which indicates that these changes are due to the foreign body response to implantation. PMID:26300717

Characterization of the hollow fiber assay for the determination of microtubule disruption in vivo.

PubMed

Suggitt, Marie; Swaine, David J; Pettit, George R; Bibby, Michael C

2004-10-01

The hollow fiber assay is used successfully as a routine in vivo screening model to quantitatively define anticancer activity by the National Cancer Institute. This study investigates whether the hollow fiber assay can be used as a short-term in vivo model to demonstrate specific pharmacodynamic end points, namely microtubule and cell cycle disruption. The growth of A549 cells was characterized within hollow fibers over 5 days in vivo at both subcutaneous (s.c.) and intraperitoneal (i.p.) sites. Drugs were administered on day 4 (i.p.). At 24 hours, cells were retrieved from fibers at both i.p. and s.c. sites of paclitaxel-treated (20 mg/kg) and combretastatin A1 phosphate-treated (150 mg/kg) mice. Cell cycle analysis after paclitaxel treatment revealed a mean G(2)-M phase population of 48.04% (i.p.) and 25.76% (s.c.) compared with vehicle group mice (6.78 and 5.56%, respectively; P = <0.001 and 0.005, respectively). Tumor cells retrieved from combretastatin A1 phosphate-treated mice had a mean G2-M phase population of 36.3% (i.p.) and 29.36% (s.c.) compared with cells retrieved from vehicle group mice (5.58 and 5.49%, respectively; P = <0.001). Using fluorescence and laser-confocal microscopy, paclitaxel was revealed to induce the formation of spindle asters and tubulin polymerization. Combretastatin A1 phosphate was shown to hold cells in mitosis. Changes in nuclear morphology were also observed. These data demonstrate that the hollow fiber assay can be used as a short-term in vivo model for studying the pharmacodynamic effects of both standard and novel compounds on microtubules. Evidence has also been provided to support the routine use of the in vivo hollow fiber assay for demonstrating the mechanism of action of a drug.

Degradation of aqueous synthesized CdTe/ZnS quantum dots in mice: differential blood kinetics and biodistribution of cadmium and tellurium

PubMed Central

2013-01-01

Background Quantum dots (QDs) have been used as novel fluorescent nanoprobes for various bioapplications. The degradation of QDs, and consequent release of free cadmium ions, have been suggested to be the causes of their overall toxicity. However, in contrast to sufficient investigations regarding the biological fate of QDs, a paucity of studies have reported their chemical fate in vivo. Therefore, the overall aim of our study was to understand the chemical fate of QDs in vivo and explore analytical techniques or methods that could be used to define the chemical fate of QDs in vivo. Methods Male ICR mice were administered a single intravenous dose (0.2 μmol/kg) of aqueous synthesized CdTe/ZnS aqQDs. Inductively coupled plasma-mass spectrometry (ICP-MS) was used to simultaneously measure the concentrations of cadmium (Cd) and tellurium (Te) in the blood and tissues over the course of a 28 day period. We compared the blood kinetic parameters and biodistributions of Cd and Te, and used the molar ratio of Cd:Te as a marker for QDs degradation. Results Cd and Te display different blood kinetics and biodistribution profiles. The Cd:Te ratio in the blood did not vary significantly within the first hour compared with intact CdTe/ZnS aqQDs. The Cd:Te ratio decreased gradually over time from the 6 h time point on. Cd accumulated in the liver, kidneys, and spleen. Te was distributed primarily to the kidneys. Sharp time-dependent increases in the Cd:Te ratio were found in liver tissues. Conclusions QDs can undergo degradation in vivo. In vitro, QDs are chemically stable and do not elicit the same biological responses or consequences as they do in vivo. Our methods might provide valuable information regarding the degradation of QDs in vivo and may enable the design and development of QDs for biological and biomedical applications. PMID:23915017

Degradation of aqueous synthesized CdTe/ZnS quantum dots in mice: differential blood kinetics and biodistribution of cadmium and tellurium.

PubMed

Liu, Na; Mu, Ying; Chen, Yi; Sun, Hubo; Han, Sihai; Wang, Mengmeng; Wang, Hui; Li, Yanbo; Xu, Qian; Huang, Peili; Sun, Zhiwei

2013-08-06

Quantum dots (QDs) have been used as novel fluorescent nanoprobes for various bioapplications. The degradation of QDs, and consequent release of free cadmium ions, have been suggested to be the causes of their overall toxicity. However, in contrast to sufficient investigations regarding the biological fate of QDs, a paucity of studies have reported their chemical fate in vivo. Therefore, the overall aim of our study was to understand the chemical fate of QDs in vivo and explore analytical techniques or methods that could be used to define the chemical fate of QDs in vivo. Male ICR mice were administered a single intravenous dose (0.2 μmol/kg) of aqueous synthesized CdTe/ZnS aqQDs. Inductively coupled plasma-mass spectrometry (ICP-MS) was used to simultaneously measure the concentrations of cadmium (Cd) and tellurium (Te) in the blood and tissues over the course of a 28 day period. We compared the blood kinetic parameters and biodistributions of Cd and Te, and used the molar ratio of Cd:Te as a marker for QDs degradation. Cd and Te display different blood kinetics and biodistribution profiles. The Cd:Te ratio in the blood did not vary significantly within the first hour compared with intact CdTe/ZnS aqQDs. The Cd:Te ratio decreased gradually over time from the 6 h time point on. Cd accumulated in the liver, kidneys, and spleen. Te was distributed primarily to the kidneys. Sharp time-dependent increases in the Cd:Te ratio were found in liver tissues. QDs can undergo degradation in vivo. In vitro, QDs are chemically stable and do not elicit the same biological responses or consequences as they do in vivo. Our methods might provide valuable information regarding the degradation of QDs in vivo and may enable the design and development of QDs for biological and biomedical applications.

Liver cancer: increased microwave delivery to ablation zone with cooled-shaft antenna--experimental and clinical studies.

PubMed

Kuang, Ming; Lu, Ming D; Xie, Xiao Y; Xu, Hui X; Mo, Li Q; Liu, Guang J; Xu, Zuo F; Zheng, Yan L; Liang, Jin Y

2007-03-01

To prospectively investigate whether the ablation zone induced with microwaves could be increased by delivering greater energy with a cooled-shaft antenna. All studies were animal care and ethics committee approved. Written informed consent was obtained from all patients. Microwave ablation was performed by using a cooled-shaft antenna in 48 ex vivo and 12 in vivo experiments with porcine livers. The coagulation diameters achieved in different microwave ablation parameter groups (60-90 W for 5-25 minutes) were compared. Ninety patients (78 men, 12 women; mean age, 53 years; age range, 20-82 years) with 133 0.8-8.0-cm (mean, 2.7 cm +/- 1.5 [standard deviation]) primary or metastatic liver cancers were treated with the same microwave ablation technique. Complete ablation (CA) and local tumor progression (LTP) rates were determined. Generalized estimating equations were used to compare differences in tumor size, ablation zone diameter, and CA and LTP rates between different patient subgroups. In the ex vivo livers, in vivo livers, and liver cancers, one application of microwave energy with 80 W for 25 minutes produced mean coagulation diameters of 5.6 x 7.4 cm, 3.5 x 5.9 cm, and 3.6 x 5.0 cm, respectively. Skin burn was not observed. CA rates in small (

Differences in the Electrophysiological Properties of Mouse Somatosensory Layer 2/3 Neurons In Vivo and Slice Stem from Intrinsic Sources Rather than a Network-Generated High Conductance State

PubMed Central

2018-01-01

Abstract Synaptic activity in vivo can potentially alter the integration properties of neurons. Using recordings in awake mice, we targeted somatosensory layer 2/3 pyramidal neurons and compared neuronal properties with those from slices. Pyramidal cells in vivo had lower resistance and gain values, as well as broader spikes and increased spike frequency adaptation compared to the same cells in slices. Increasing conductance in neurons using dynamic clamp to levels observed in vivo, however, did not lessen the differences between in vivo and slice conditions. Further, local application of tetrodotoxin (TTX) in vivo blocked synaptic-mediated membrane voltage fluctuations but had little impact on pyramidal cell membrane input resistance and time constant values. Differences in electrophysiological properties of layer 2/3 neurons in mouse somatosensory cortex, therefore, stem from intrinsic sources separate from synaptic-mediated membrane voltage fluctuations. PMID:29662946

Voxel size dependency, reproducibility and sensitivity of an in vivo bone loading estimation algorithm

PubMed Central

Christen, Patrik; Schulte, Friederike A.; Zwahlen, Alexander; van Rietbergen, Bert; Boutroy, Stephanie; Melton, L. Joseph; Amin, Shreyasee; Khosla, Sundeep; Goldhahn, Jörg; Müller, Ralph

2016-01-01

A bone loading estimation algorithm was previously developed that provides in vivo loading conditions required for in vivo bone remodelling simulations. The algorithm derives a bone's loading history from its microstructure as assessed by high-resolution (HR) computed tomography (CT). This reverse engineering approach showed accurate and realistic results based on micro-CT and HR-peripheral quantitative CT images. However, its voxel size dependency, reproducibility and sensitivity still need to be investigated, which is the purpose of this study. Voxel size dependency was tested on cadaveric distal radii with micro-CT images scanned at 25 µm and downscaled to 50, 61, 75, 82, 100, 125 and 150 µm. Reproducibility was calculated with repeated in vitro as well as in vivo HR-pQCT measurements at 82 µm. Sensitivity was defined using HR-pQCT images from women with fracture versus non-fracture, and low versus high bone volume fraction, expecting similar and different loading histories, respectively. Our results indicate that the algorithm is voxel size independent within an average (maximum) error of 8.2% (32.9%) at 61 µm, but that the dependency increases considerably at voxel sizes bigger than 82 µm. In vitro and in vivo reproducibility are up to 4.5% and 10.2%, respectively, which is comparable to other in vitro studies and slightly higher than in other in vivo studies. Subjects with different bone volume fraction were clearly distinguished but not subjects with and without fracture. This is in agreement with bone adapting to customary loading but not to fall loads. We conclude that the in vivo bone loading estimation algorithm provides reproducible, sensitive and fairly voxel size independent results at up to 82 µm, but that smaller voxel sizes would be advantageous. PMID:26790999

Biology and Genomics of an Historic Therapeutic Escherichia coli Bacteriophage Collection.

PubMed

Baig, Abiyad; Colom, Joan; Barrow, Paul; Schouler, Catherine; Moodley, Arshnee; Lavigne, Rob; Atterbury, Robert

2017-01-01

We have performed microbiological and genomic characterization of an historic collection of nine bacteriophages, specifically infecting a K1 E. coli O18:K1:H7 ColV + strain. These phages were isolated from sewage and tested for their efficacy in vivo for the treatment of systemic E. coli infection in a mouse infection model by Smith and Huggins (1982). The aim of the study was to identify common microbiological and genomic characteristics, which co-relate to the performance of these phages in in vivo study. These features will allow an informed selection of phages for use as therapeutic agents. Transmission electron microscopy showed that six of the nine phages were Podoviridae and the remaining three were Siphoviridae . The four best performing phages in vivo belonged to the Podoviridae family. In vitro , these phages exhibited very short latent and rise periods in our study. In agreement with their microbiological profiles, characterization by genome sequencing showed that all six podoviruses belong to the Autographivirinae subfamily. Of these, four were isolates of the same species (99% identity), whereas two had divergent genomes compared to other podoviruses. The Siphoviridae phages, which were moderate to poor performers in vivo , exhibited longer latent and rise periods in vitro . Two of the three siphoviruses were closely related to each other (99% identity), but all can be associated with the Guernseyvirinae subfamily. Genome sequence comparison of both types of phages showed that a gene encoding for DNA-dependent RNA polymerase was only present in phages with faster replication cycle, which may account for their better performance in vivo . These data define a combination of microbiological, genomic and in vivo characteristics which allow a more rational evaluation of the original in vivo data and pave the way for the selection of phages for future phage therapy trails.

Continuous glucose monitoring in subcutaneous tissue using factory-calibrated sensors: a pilot study.

PubMed

Hoss, Udo; Jeddi, Iman; Schulz, Mark; Budiman, Erwin; Bhogal, Claire; McGarraugh, Geoffrey

2010-08-01

Commercial continuous subcutaneous glucose monitors require in vivo calibration using capillary blood glucose tests. Feasibility of factory calibration, i.e., sensor batch characterization in vitro with no further need for in vivo calibration, requires a predictable and stable in vivo sensor sensitivity and limited inter- and intra-subject variation of the ratio of interstitial to blood glucose concentration. Twelve volunteers wore two FreeStyle Navigator (Abbott Diabetes Care, Alameda, CA) continuous glucose monitoring systems for 5 days in parallel for two consecutive sensor wears (four sensors per subject, 48 sensors total). Sensors from a prototype sensor lot with a low variability in glucose sensitivity were used for the study. Median sensor sensitivity values based on capillary blood glucose were calculated per sensor and compared for inter- and intra-subject variation. Mean absolute relative difference (MARD) calculation and error grid analysis were performed using a single calibration factor for all sensors to simulate factory calibration and compared to standard fingerstick calibration. Sensor sensitivity variation in vitro was 4.6%, which increased to 8.3% in vivo (P < 0.0001). Analysis of variance revealed no significant inter-subject differences in sensor sensitivity (P = 0.134). Applying a single universal calibration factor retrospectively to all sensors resulted in a MARD of 10.4% and 88.1% of values in Clarke Error Grid Zone A, compared to a MARD of 10.9% and 86% of values in Error Grid Zone A for fingerstick calibration. Factory calibration of sensors for continuous subcutaneous glucose monitoring is feasible with similar accuracy to standard fingerstick calibration. Additional data are required to confirm this result in subjects with diabetes.

Cell migration, viability and tissue reaction of calcium hypochlorite based-solutions irrigants: An in vitro and in vivo study.

PubMed

Blattes, Gabriela Bess Ferraz; Mestieri, Leticia Boldrin; Böttcher, Daiana Elisabeth; Fossati, Anna Cristina Medeiros; Montagner, Francisco; Grecca, Fabiana Soares

2017-01-01

This study aimed to analyze in vitro cytotoxicity to cultured 3T3 fibroblasts and in vivo inflammatory reaction in rats by calcium hypochlorite (Ca(OCl) 2 ) solutions compared with sodium hypochlorite (NaOCl) solutions. Cultured 3T3 fibroblasts were exposed to different concentrations of (Ca(OCl) 2 ) and NaOCl solutions, and a scratch assay was performed. The viability rate was analyzed with trypan blue assay. Both solutions of 1% and 2.5% concentrations were injected into the subcutaneous tissue of 18 male Wistar rats aged 18 weeks. The inflammatory tissue reaction was evaluated at 2h, 24h, and 14days after the injections. The samples were qualitatively analyzed using a light microscope. Statistical analysis was performed with ANOVA and Tukey post hoc tests for in vitro assays and Kruskal-Wallis and Dunn post hoc tests for in vivo assays (α=0.05). In the scratch assay, Ca(OCl) 2 showed no significant difference compared with the control group (culture medium) at 24h (p<0.05). Solutions of 0.0075% and 0.005% NaOCl and Ca(OCl) 2 concentrations presented similar results compared with those in the positive control group (hydrogen peroxide) (p>0.05) in the trypan blue assay. In the in vivo assay, 1% Ca(OCl) 2 group showed a significant decrease in neutrophils at 2h and 24h (p=0.041) and 2h and 14days (p=0.017). There was no statistically significant difference for lymphocyte/plasmocyte and macrophage counts among the different concentration groups. Ca(OCl) 2 showed favorable results of viability and induced a low-level inflammatory response. Ca(OCl) 2 presented acceptable cytotoxicity and biocompatibility as an irrigant solution. Copyright © 2016 Elsevier Ltd. All rights reserved.

Antitumor effects of hydroxycamptothecin-loaded poly[ethylene glycol]-poly [gamma-benzyl-L-glutamate] micelles against oral squamous cell carcinoma.

PubMed

Ding, Xue-Qiang; Chen, Dan; Wang, An-Xun; Li, Su; Chen, Yu; Wang, Ji

2007-01-01

Therapeutic use of hydroxycamptothecin (HCPT), a promising antitumor agent, is limited by its poor solubility and rapid destruction. Amphiphilic block copolymer micelle carriers possess significant potential for improving drug solubility and stability. Poly[ethylene glycol]-poly[gamma-benzyl-L-glutamate] (PEG-PBLG) micelles were prepared and loaded with the active lactone form of HCPT using an uncomplicated dialysis method. HPLC and scanning electron microscopy studies revealed an encapsulation efficiency of 56.8% and a core-shell figure with a mean diameter of 200 nm. Encapsulated HCPT lactone was compared with the less active, open ring-carboxylated HCPT-Na+ soluble form generated in vivo from the free active lactone for activity against oral squamous cell carcinoma. Cytotoxicity in vitro was measured in cultured Tca8113 cells by the MTT assay and microscopy techniques. The golden hamster cheek pouch squamous cell carcinoma model was employed for in vivo studies; encapsulated lactone and open ring-carboxylated forms of HCPT were administered intraperitoneally, followed by determinations of tumor growth rate and inhibition ratio. PEG-PBLG micelles were not cytotoxic in vitro. At 48 h of treatment, open ring-carboxylated HCPT proved significantly more cytotoxic in vitro than encapsulated HCPT lactone. At 96 h, however, the open ring-carboxylated and encapsulated drugs displayed comparable in vitro cytotoxicities. In the in vivo squamous cell carcinoma model, encapsulated HCPT lactone produced greater and more prolonged tumor suppression compared to the open ring-carboxylated form. The antitumor effects of HCPT/PEG-PBLG micelles against oral squamous cell carcinoma in vivo are concluded to be superior to those exerted by open ring-carboxylated HCPT.

In Vivo Microdialysis for Dynamic Monitoring of the Effectiveness of Nano-liposomes as Vehicles for Topical Psoralen Application.

PubMed

Zhang, Hongyu; Zhang, Kai; Li, Zhe; Zhao, Jihui; Zhang, Yongtai; Feng, Nianping

2017-01-01

In this study, the skin permeation of liposomes containing psoralen was investigated by in vivo skin microdialysis. Psoralen-loaded nano-sized liposomes were prepared with a mean size of 117.5 nm and a polydispersity index of 0.21, indicating the uniform dispersion of phosphatidylcholine vesicles in the liposomal solution. Based on in vivo microdialysis experiments, the drug concentration in local deep skin of rat increased rapidly and reached a peak concentration (C max ) of 319.35±23.72 µg/mL at 180 min, and decreased slowly thereafter. The local area under the concentration-time curve (AUC) 0-t was 3.81-fold higher than the compared aqueous suspension. The in vivo systemic pharmacokinetics were in agreement with the microdialysis results, in view of the C max and AUC 0-t from liposomal group were both significantly higher (p<0.05) than the compared group. Liposome-associated transdermal psoralen delivery was significantly more effective than delivery via an aqueous suspension. The enhanced skin permeability may be associated with improved skin hydration, lipid exchange and fusion with the stratum corneum (SC), and changes in SC structure, promoting drug permeation into deep skin. After 10 h of treatment with the perfusate, the microstructure of the microdialysis probe exhibited no obvious differences with control probes. The skin surface and the tissue around the probe showed no swelling or inflammation. These findings indicated that liposomes effectively enhanced the skin deposition of psoralen and showed good biocompatibility with skin tissues; additionally, ethanol at a low concentration in ringer's solution is an alternative perfusate for in vivo skin microdialysis studies.

In vitro and ex vivo characterisation of an in situ gelling formulation for sustained lidocaine release with potential use following knee arthroplasty.

PubMed

Sharma, Manisha; Chandramouli, Kaushik; Curley, Louise; Pontre, Beau; Reilly, Keryn; Munro, Jacob; Hill, Andrew; Young, Simon; Svirskis, Darren

2018-06-01

Sustained lidocaine release via a thermoresponsive poloxamer-based in situ gelling system has the potential to alleviate pain following knee arthroplasty. A previously developed formulation showed a promising drug release profile in synthetic phosphate-buffered saline (PBS). To support the translation of this formulation, ex vivo characterisation was warranted. This study therefore aimed (1) to modify the previously developed formulation to reduce the burst release, (2) to compare the release behaviour into ex vivo human intra-articular fluid (IAF) and PBS and (3) to determine the formulation spread in an ex vivo human knee using magnetic resonance imaging (MRI). All formulations provided sustained release out to 72 h; polyvinyl pyrrolidone was the most effective additive yielding a small yet significant decrease (p < 0.05) in the burst release. Release of lidocaine from the formulation occurred significantly faster into IAF compared to PBS (1.4 times greater release in the first 24 h), correlating with faster rates of gel erosion in IAF. Injection was easily achieved through a 21-gauge (G) needle into the synovial space of a human cadaveric knee, and MRI scans revealed effective spreading of the formulation throughout the joint cavity. The pattern of spread is promising for the drug to reach the widespread nerve endings in the joint capsule; the effect of this spread on release in an in vivo setting will be the subject of future studies. The demonstrated properties indicate that the in situ gelling formulation has the potential to be used clinically to treat post-operative pain following knee arthroplasty.

Slowly Digestible Carbohydrate for Balanced Energy: In Vitro and In Vivo Evidence

PubMed Central

Gourineni, Vishnupriya; Stewart, Maria L.; Skorge, Rob; Sekula, Bernard C.

2017-01-01

There is growing interest among consumers in foods for sustained energy management, and an increasing number of ingredients are emerging to address this demand. The SUSTRA™ 2434 slowly digestible carbohydrate is a blend of tapioca flour and corn starch, with the potential to provide balanced energy after a meal. The aim of the study was to characterize this starch’s digestion profile in vitro (modified Englyst assay) and in vivo (intact and cecectomized rooster study), and to determine its effects on available energy, by measuring post-prandial glycemia in healthy adults (n = 14), in a randomized, double-blind, placebo-controlled, cross-over study, with two food forms: cold-pressed bar and pudding. The in vitro starch digestion yielded a high slowly digestible fraction (51%) compared to maltodextrin (9%). In the rooster digestibility model, the starch was highly digestible (94%). Consumption of slowly digestible starch (SDS), in an instant pudding or bar, yielded a significantly lower glycemic index compared to a control. At individual time points, the SDS bar and pudding yielded blood glucose levels with significantly lower values at 30–60 min and significantly higher values at 120–240 min, demonstrating a balanced energy release. This is the first study to comprehensively characterize the physiological responses to slowly digestible starch (tapioca and corn blend) in in vitro and in vivo studies. PMID:29125542

Preliminary investigation of topical nitroglycerin formulations containing natural wound healing agent in diabetes-induced foot ulcer.

PubMed

Hotkar, Mukesh S; Avachat, Amelia M; Bhosale, Sagar S; Oswal, Yogesh M

2015-04-01

Nitroglycerin (NTG) is an organic nitrate rapidly denitrated by enzymes to release free radical nitric oxide and shows improved wound healing and tissue protection from oxidative damage. The purpose of this study was to evaluate whether topical application of NTG in the form of gel/ointment along with a natural wound healing agent, aloe vera, would bring about wound healing by using diabetes-induced foot ulcer model and rat excision wound model. All these formulations were evaluated for pH, viscosity, drug content and ex vivo diffusion studies using rat skin. Based on ex vivo permeation studies, the formulation consisting of carbopol 974p as a gelling agent and aloe vera was found to be suitable. The in vivo study used streptozotocin-induced diabetic foot ulcer and rat excision wound models to analyse wound healing activity. The wound size in animals of all treated groups was significantly reduced compared with that of the diabetic control and marketed treated animals. This study showed that the gel formed with carbopol 974p (1%) and aloe vera promotes significant wound healing and closure in diabetic rats compared with the commercial product and provides a promising product to be used in diabetes-induced foot ulcer. © 2013 The Authors. International Wound Journal © 2013 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Improved oral bioavailability of valsartan using proliposomes: design, characterization and in vivo pharmacokinetics.

PubMed

Nekkanti, Vijaykumar; Venkatesan, Natarajan; Wang, Zhijun; Betageri, Guru V

2015-01-01

The objective of our investigational work was to develop a proliposomal formulation to improve the oral bioavailability of valsartan. Proliposomes were formulated by thin film hydration technique using different ratios of phospholipids:drug:cholesterol. The prepared proliposomes were evaluated for vesicle size, encapsulation efficiency, morphological properties, in vitro drug release, in vitro permeability and in vivo pharmacokinetics. In vitro drug-release studies were performed in simulated gastric fluid (pH 1.2) and purified water using dialysis bag method. In vitro drug permeation was studied using parallel artificial membrane permeation assay (PAMPA), Caco-2 monolayer and everted rat intestinal perfusion techniques. In vivo pharmacokinetic studies were conducted in male Sprague Dawley (SD) rats. Among the proliposomal formulations, F-V was found to have the highest encapsulation efficiency of 95.6 ± 2.9% with a vesicle size of 364.1 ± 14.9 nm. The in vitro dissolution studies indicated an improved drug release from proliposomal formulation, F-V in comparison to pure drug suspension in both, purified water and pH 1.2 dissolution media after 12 h. Permeability across PAMPA, Caco-2 cell and everted rat intestinal perfusion studies were higher with F-V formulation as compared to pure drug. Following single oral administration of F-V formulation, a relative bioavailability of 202.36% was achieved as compared to pure valsartan.

Parallel microfluidic synthesis of size-tunable polymeric nanoparticles using 3D flow focusing towards in vivo study

PubMed Central

Lim, Jong-Min; Bertrand, Nicolas; Valencia, Pedro M.; Rhee, Minsoung; Langer, Robert; Jon, Sangyong; Farokhzad, Omid C.; Karnik, Rohit

2014-01-01

Microfluidic synthesis of nanoparticles (NPs) can enhance the controllability and reproducibility in physicochemical properties of NPs compared to bulk synthesis methods. However, applications of microfluidic synthesis are typically limited to in vitro studies due to low production rates. Herein, we report the parallelization of NP synthesis by 3D hydrodynamic flow focusing (HFF) using a multilayer microfluidic system to enhance the production rate without losing the advantages of reproducibility, controllability, and robustness. Using parallel 3D HFF, polymeric poly(lactide-co-glycolide)-b-polyethyleneglycol (PLGA-PEG) NPs with sizes tunable in the range of 13–150 nm could be synthesized reproducibly with high production rate. As a proof of concept, we used this system to perform in vivo pharmacokinetic and biodistribution study of small (20 nm diameter) PLGA-PEG NPs that are otherwise difficult to synthesize. Microfluidic parallelization thus enables synthesis of NPs with tunable properties with production rates suitable for both in vitro and in vivo studies. PMID:23969105

Antioxidant and Antilipid Peroxidation Potential of Supercritical Fluid Extract and Ethanol Extract of Leaves of Vitex Negundo Linn.

PubMed Central

Nagarsekar, K. S.; Nagarsenker, M. S.; Kulkarni, S. R.

2011-01-01

Supercritical fluid extract and ethanol extract of Vitex negundo Linn. were subjected to the chromatographic evaluation for identification of their constituents. Free radical scavenging activity of both extracts was studied by subjecting them to DPPH assay. IC50 values of ethanol and supercritical fluid extract of Vitex negundo indicate that ethanol extract has stronger reducing potential and ability to scavenge free radicals as compared to the supercritical fluid extract. The in vivo effect of extracts on lipid peroxidation was studied using ethanol induced oxidative stress model in rat. Ingestion of extracts for 14 days exhibited significant reduction in plasma MDA level of stressed animals. Ethanol extract exhibited higher in vivo antilipid peroxidation potential as compared to supercritical fluid extract which correlated well with radical scavenging potential of extract. PMID:22707827

Improved oral bioavailability of poorly water-soluble indirubin by a supersaturatable self-microemulsifying drug delivery system.

PubMed

Chen, Zhi-Qiang; Liu, Ying; Zhao, Ji-Hui; Wang, Lan; Feng, Nian-Ping

2012-01-01

Indirubin, isolated from the leaves of the Chinese herb Isatis tinctoria L, is a protein kinase inhibitor and promising antitumor agent. However, the poor water solubility of indirubin has limited its application. In this study, a supersaturatable self-microemulsifying drug delivery system (S-SMEDDS) was developed to improve the oral bioavailability of indirubin. A prototype S-SMEDDS was designed using solubility studies and phase diagram construction. Precipitation inhibitors were selected from hydrophilic polymers according to their crystallization-inhibiting capacity through in vitro precipitation tests. In vitro release of indirubin from S-SMEDDS was examined to investigate its likely release behavior in vivo. The in vivo bioavailability of indirubin from S-SMEDDS and from SMEDDS was compared in rats. The prototype formulation of S-SMEDDS comprised Maisine™ 35-1:Cremophor(®) EL:Transcutol(®) P (15:40:45, w/w/w). Polyvinylpyrrolidone K17, a hydrophilic polymer, was used as a precipitation inhibitor based on its better crystallization-inhibiting capacity compared with polyethylene glycol 4000 and hydroxypropyl methylcellulose. In vitro release analysis showed more rapid drug release from S-SMEDDS than from SMEDDS. In vivo bioavailability analysis in rats indicated that improved oral absorption was achieved and that the relative bioavailability of S-SMEDDS was 129.5% compared with SMEDDS. The novel S-SMEDDS developed in this study increased the dissolution rate and improved the oral bioavailability of indirubin in rats. The results suggest that S-SMEDDS is a superior means of oral delivery of indirubin.

In vitro and in vivo anthelmintic activity of seed extract of Coriandrum sativum compared to Niclosamid against Hymenolepis nana infection.

PubMed

Hosseinzadeh, Samaneh; Ghalesefidi, Maryam Jamshidian; Azami, Mehdi; Mohaghegh, Mohammad Ali; Hejazi, Seyed Hossein; Ghomashlooyan, Mohsen

2016-12-01

Phytotherapy can be an alternative for the control of gastrointestinal parasites in human and animals. Coriander ( Coriandrum sativum L.) is a medicinal plant which grown as a spice crop all over the world. The seeds of this plant have been used to treat parasitic disease, indigestion, diabetes, rheumatism and pain in the joints. This study was carried out to compare the efficacy of Niclosamid and alcoholic seed extract of C. sativum on Hymenolepis nana infection, in vivo and vitro. For in vivo study, Balb/c mice were used, to compare the efficacy of 50 mg/kg body weight (B.W) of Niclosamid with different doses of alcoholic extracts of C. sativum (250, 500, and 750 mg/kg B.W). It was found that the efficacy of Niclosamid had reached 100 % after 11 days post treatment, while the efficacy of 500 and 750 mg/kg B.W of C. sativum reached to 100 % after 15 days after treatment. For in vitro study, special nutrient broth media was used. It was found that the addition of 1000 mg/ml of Niclosamid had paralyzed and killed worms within 5 min, while C. sativum killed them within 30 min. Our results showed that extract of C. sativum has good effect against H. nana and could be use in traditional medicine for treatment of parasitic disease.

A dual-slot microwave antenna for more spherical ablation zones: ex vivo and in vivo validation.

PubMed

Chiang, Jason; Hynes, Kieran A; Bedoya, Mariajose; Brace, Christopher L

2013-08-01

To compare the performance of a microwave antenna design with two annular slots to that of a monopole antenna design in creating a more spherical ablation zone. Animal care and use committee approval was obtained before in vivo experiments were performed. Microwave ablation zones were created by using dual-slot and monopole control antennas for 2, 5, and 10 minutes at 50 and 100 W in ex vivo bovine livers. Dual-slot and monopole antennas were then used to create ablation zones at 100 W for 5 minutes in in vivo porcine livers, which also underwent intraprocedural imaging. Ablation diameter, length, and aspect ratio (diameter ÷ length) were measured at gross pathologic examination and compared at each combination of power and time by using the paired Student t test. A P value less than .05 was considered to indicate a significant difference. Aspect ratios closer to 1 reflected a more spherical ablation zone. The dual-slot antenna created ablation zones with a higher aspect ratio at 50 W for 2 minutes (0.75 vs 0.53, P = .003) and 5 minutes (0.82 vs 0.63, P = .053) than did the monopole antenna in ex vivo liver tissue, although the difference was only significant at 2 minutes. At 100 W, the dual-slot antenna had a significantly higher aspect ratio at 2 minutes (0.52 vs 0.42, P = .002). In vivo studies showed significantly higher aspect ratios at 100 W for 5 minutes (0.63 vs 0.53, respectively, P = .029). Intraprocedural imaging confirmed this characterization, showing higher rates of ablation zone growth and heating primarily at the early stages of the ablation procedure when the dual-slot antenna was used. The dual-slot microwave antenna created a more spherical ablation zone than did the monopole antenna both in vivo and ex vivo liver tissue. Greater control over power delivery can potentially extend the advantages of the dual-slot antenna design to higher power and longer treatment times.

Tailored nanostructured platforms for boosting transcorneal permeation: Box–Behnken statistical optimization, comprehensive in vitro, ex vivo and in vivo characterization

PubMed Central

Elsayed, Ibrahim; Sayed, Sinar

2017-01-01

Ocular drug delivery systems suffer from rapid drainage, intractable corneal permeation and short dosing intervals. Transcorneal drug permeation could increase the drug availability and efficiency in the aqueous humor. The aim of this study was to develop and optimize nanostructured formulations to provide accurate doses, long contact time and enhanced drug permeation. Nanovesicles were designed based on Box–Behnken model and prepared using the thin film hydration technique. The formed nanodispersions were evaluated by measuring the particle size, polydispersity index, zeta potential, entrapment efficiency and gelation temperature. The obtained desirability values were utilized to develop an optimized nanostructured in situ gel and insert. The optimized formulations were imaged by transmission and scanning electron microscopes. In addition, rheological characters, in vitro drug diffusion, ex vivo and in vivo permeation and safety of the optimized formulation were investigated. The optimized insert formulation was found to have a relatively lower viscosity, higher diffusion, ex vivo and in vivo permeation, when compared to the optimized in situ gel. So, the lyophilized nanostructured insert could be considered as a promising carrier and transporter for drugs across the cornea with high biocompatibility and effectiveness. PMID:29133980

Longitudinal in vivo muscle function analysis of the DMSXL mouse model of myotonic dystrophy type 1.

PubMed

Decostre, Valérie; Vignaud, Alban; Matot, Béatrice; Huguet, Aline; Ledoux, Isabelle; Bertil, Emilie; Gjata, Bernard; Carlier, Pierre G; Gourdon, Geneviève; Hogrel, Jean-Yves

2013-12-01

Myotonic dystrophy is the most common adult muscle dystrophy. In view of emerging therapies, which use animal models as a proof of principle, the development of reliable outcome measures for in vivo longitudinal study of mouse skeletal muscle function is becoming crucial. To satisfy this need, we have developed a device to measure ankle dorsi- and plantarflexion torque in rodents. We present an in vivo 8-month longitudinal study of the contractile properties of the skeletal muscles of the DMSXL mouse model of myotonic dystrophy type 1. Between 4 and 12 months of age, we observed a reduction in muscle strength in the ankle dorsi- and plantarflexors of DMSXL compared to control mice although the strength per muscle cross-section was normal. Mild steady myotonia but no abnormal muscle fatigue was also observed in the DMSXL mice. Magnetic resonance imaging and histological analysis performed at the end of the study showed respectively reduced muscle cross-section area and smaller muscle fibre diameter in DMSXL mice. In conclusion, our study demonstrates the feasibility of carrying out longitudinal in vivo studies of muscle function over several months in a mouse model of myotonic dystrophy confirming the feasibility of this method to test preclinical therapeutics. Copyright © 2013 Elsevier B.V. All rights reserved.

In Vivo Confocal Microscopy of Corneal Nerves in Health and Disease

PubMed Central

Cruzat, Andrea; Qazi, Yureeda; Hamrah, Pedram

2016-01-01

In vivo confocal microscopy (IVCM) is becoming an indispensable tool for studying corneal physiology and disease. Enabling the dissection of corneal architecture at a cellular level, this technique offers fast and noninvasive in vivo imaging of the cornea with images comparable to that of ex vivo histochemical techniques. Corneal nerves bear substantial relevance to clinicians and scientists alike, given their pivotal roles in regulation of corneal sensation, maintenance of epithelial integrity, and proliferation and promotion of wound healing. Thus, IVCM offers a unique method to study corneal nerve alterations in a myriad of conditions, such as ocular and systemic diseases and following corneal surgery, without altering the tissue microenvironment. Of particular interest has been the correlation of corneal subbasal nerves to their function, which has been studied in normal eyes, contact lens wearers, and patients with keratoconus, infectious keratitis, corneal dystrophies, and neurotrophic keratopathy. Longitudinal studies have applied IVCM to investigate the effects of corneal surgery on nerves, demonstrating their regenerative capacity. IVCM is increasingly important in the diagnosis and management of systemic conditions such as peripheral diabetic neuropathy and, more recently, in ocular diseases. In this review, we outline the principles and applications of IVCM in the study of corneal nerves in various ocular and systemic diseases. PMID:27771327

Modeling Fetal Alcohol Spectrum Disorder: validating an ex vivo primary hippocampal cell culture system

PubMed Central

Tunc-Ozcan, Elif; Ferreira, Adriana B.; Redei, Eva E.

2016-01-01

Background Fetal Alcohol Spectrum Disorder (FASD) is the leading non-genetic cause of mental retardation. There are no treatments for FASD to date. Preclinical in vivo and in vitro studies could help in identifying novel drug targets as for other diseases. Here, we describe an ex vivo model that combines the physiological advantages of prenatal ethanol (E) exposure in vivo with the uniformity of primary fetal hippocampal culture to characterize the effects of prenatal E. The insulin signaling pathways are known to be involved in hippocampal functions. Therefore, we compared the expression of insulin signaling pathway genes between fetal hippocampi (in vivo) and primary hippocampal culture (ex vivo). The similarity of prenatal E effects in these two paradigms would deem the ex vivo culture acceptable to screen possible treatments for FASD. Methods Pregnant Sprague-Dawley rats received one of three diets: ad libitum standard lab chow (control-C), isocaloric pair-fed (PF, nutritional control), and E containing liquid diets from gestational day (GD) 8. Fetal male and female hippocampi were collected either on GD21 (in vivo) or on GD18 for primary culture (ex vivo). Transcript levels of Igf2, Igf2r, Insr, Grb10, Rasgrf1 and Zac1 were measured by RT-qPCR. Results Hippocampal transcript levels differed by prenatal treatment in both males and females with sex differences observed in the expression of Igf2 and Insr. The effect of prenatal E on the hippocampal expression of the insulin pathway genes was parallel in the in vivo and the ex vivo conditions. Conclusions The similarity of gene expression changes in response to prenatal E between the in vivo and the ex vivo conditions ascertain that these effects are already set in the fetal hippocampus at GD18. This strengthens the feasibility of the ex vivo primary hippocampal culture as a tool to test and screen candidate drug targets for FASD. PMID:27162054

21 CFR 201.57 - Specific requirements on content and format of labeling for human prescription drug and...

Code of Federal Regulations, 2013 CFR

2013-04-01

... comparative rates of occurrence cannot be reliably determined (e.g., adverse reactions were observed only in... in vivo study designs or results (e.g., drug interaction studies), may be included in this section if...

21 CFR 201.57 - Specific requirements on content and format of labeling for human prescription drug and...

Code of Federal Regulations, 2012 CFR

2012-04-01

... comparative rates of occurrence cannot be reliably determined (e.g., adverse reactions were observed only in... in vivo study designs or results (e.g., drug interaction studies), may be included in this section if...

21 CFR 201.57 - Specific requirements on content and format of labeling for human prescription drug and...

Code of Federal Regulations, 2014 CFR

2014-04-01

... comparative rates of occurrence cannot be reliably determined (e.g., adverse reactions were observed only in... in vivo study designs or results (e.g., drug interaction studies), may be included in this section if...

Development of a discriminative biphasic in vitro dissolution test and correlation with in vivo pharmacokinetic studies for differently formulated racecadotril granules.

PubMed

Deng, Jia; Staufenbiel, Sven; Hao, Shilei; Wang, Bochu; Dashevskiy, Andriy; Bodmeier, Roland

2017-06-10

The purpose of this study was to discriminate the release behavior from three differently formulated racecadotril (BCS II) granules and to establish an in vitro-in vivo correlation. Three granule formulations of the lipophilic drug were prepared with equivalent composition but prepared with different manufacturing processes (dry granulation, wet granulation with or without binder). In vitro release of the three granules was investigated using a biphasic dissolution system (phosphate buffer pH6.8 and octanol) and compared to the conventional single phase USP II dissolution test performed under sink and non-sink conditions. In vivo studies with each granule formulation were performed in rats. Interestingly, the granule formulations exhibited pronouncedly different behavior in the different dissolution systems depending on different wetting and dissolution conditions. Single phase USP II dissolution tests lacked discrimination. In contrast, remarkable discrimination between the granule formulations was observed in the octanol phase of biphasic dissolution system with a rank order of release from granules prepared by wet granulation with binder>wet granulation without binder>dry granulation. This release order correlated well with the wettability of these granules. An excellent correlation was also established between in vitro release in the octanol phase of the biphasic test and in vivo data (R 2 =0.999). Compared to conventional dissolution methods, the biphasic method provides great potential to discriminate between only minor formulation and process changes within the same dosage form for poorly soluble drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

Selective enrichment of hypericin in malignant glioma: pioneering in vivo results.

PubMed

Noell, Susan; Mayer, Daniel; Strauss, Wolfgang S L; Tatagiba, Marcos S; Ritz, Rainer

2011-05-01

Malignant gliomas are diffuse infiltrative growing tumors with a poor prognosis despite treatment with a combination of surgery, radiotherapy and chemotherapy. It has been shown recently that complete tumor resection improves the survival time significantly. Hypericin, a component of St. Johns Wort, is one of the most powerful photosensitizers in nature. The aim of the present study was to investigate accumulation of hypericin in intracerebral implanted malignant glioma in vivo. Rats underwent stereotactic implantation of C6 glioma cells. After intravenous administration of hypericin (5 mg per kg body weight), accumulation of the compound was studied in tumor, the infiltration zone surrounding the tumor and healthy brain (contralateral hemisphere) by fluorescence microscopy between 0 and 48 h after injection. Results were compared by one-way analysis of variance. For post hoc pair-wise comparison the Tukey-Kramer HSD test was used. Accumulation of hypericin was significantly higher in C6 glioma as compared to normal tissue. Maximum hypericin uptake was achieved at 24 h after injection. Ratios of fluorescence intensity between tumor and normal tissue as well as infiltration zone and normal tissue of about 6.1:1 and 1.4:1 were found. Considering tissue auto-fluorescence, fluorescence ratios of about 19.8:1 and 2.5:1 were calculated, respectively. Therefore, hypericin seems to be quite an effective fluorescence marker for the detection of glioma in vivo. To the best of our knowledge, the present study demonstrates for the first time that hypericin accumulates selectively in intracerebral implanted C6 glioma in vivo after systemic (intravenous) administration.

Increased in vivo glial activation in patients with amyotrophic lateral sclerosis: assessed with [(11)C]-PBR28.

PubMed

Zürcher, Nicole R; Loggia, Marco L; Lawson, Robert; Chonde, Daniel B; Izquierdo-Garcia, David; Yasek, Julia E; Akeju, Oluwaseun; Catana, Ciprian; Rosen, Bruce R; Cudkowicz, Merit E; Hooker, Jacob M; Atassi, Nazem

2015-01-01

Evidence from human post mortem, in vivo and animal model studies implicates the neuroimmune system and activated microglia in the pathology of amyotrophic lateral sclerosis. The study aim was to further evaluate in vivo neuroinflammation in individuals with amyotrophic lateral sclerosis using [(11)C]-PBR28 positron emission tomography. Ten patients with amyotrophic lateral sclerosis (seven males, three females, 38-68 years) and ten age- and [(11)C]-PBR28 binding affinity-matched healthy volunteers (six males, four females, 33-65 years) completed a positron emission tomography scan. Standardized uptake values were calculated from 60 to 90 min post-injection and normalized to whole brain mean. Voxel-wise analysis showed increased binding in the motor cortices and corticospinal tracts in patients with amyotrophic lateral sclerosis compared to healthy controls (p FWE < 0.05). Region of interest analysis revealed increased [(11)C]-PBR28 binding in the precentral gyrus in patients (normalized standardized uptake value = 1.15) compared to controls (1.03, p < 0.05). In patients those values were positively correlated with upper motor neuron burden scores (r = 0.69, p < 0.05), and negatively correlated with the amyotrophic lateral sclerosis functional rating scale (r = -0.66, p < 0.05). Increased in vivo glial activation in motor cortices, that correlates with phenotype, complements previous histopathological reports. Further studies will determine the role of [(11)C]-PBR28 as a marker of treatments that target neuroinflammation.

Evaluation of transdermal delivery of nanoemulsions in ex vivo porcine skin using two-photon microscopy and confocal laser-scanning microscopy

NASA Astrophysics Data System (ADS)

Choi, Sanghoon; Kim, Jin Woong; Lee, Yong Joong; Delmas, Thomas; Kim, Changhwan; Park, Soyeun; Lee, Ho

2014-10-01

This study experimentally evaluates the self-targeting ability of asiaticoside-loaded nanoemulsions compared with nontargeted nanoemulsions in ex vivo experiments with porcine skin samples. Homebuilt two-photon and confocal laser-scanning microscopes were employed to noninvasively examine the transdermal delivery of two distinct nanoemulsions. Prior to the application of nanoemulsions, we noninvasively observed the morphology of porcine skin using two-photon microscopy. We have successfully visualized the distributions of the targeted and nontargeted nanoemulsions absorbed into the porcine skin samples. Asiaticoside-loaded nanoemulsions showed an improved ex vivo transdermal delivery through the stratum corneum compared with nonloaded nanoemulsions. As a secondary measure, nanoemulsions-applied samples were sliced in the depth direction with a surgical knife in order to obtain the complete depth-direction distribution profile of Nile red fluorescence. XZ images demonstrated that asiaticoside-loaded nanoemulsion penetrated deeper into the skin compared with nontargeted nanoemulsions. The basal layer boundary is clearly visible in the case of the asiaticoside-loaded skin sample. These results reaffirm the feasibility of using self-targeting ligands to improve permeation through the skin barrier for cosmetics and topical drug applications.

Toward the detection of intraplaque hemorrhage in carotid artery lesions using photoacoustic imaging

NASA Astrophysics Data System (ADS)

Arabul, Mustafa Umit; Heres, Maarten; Rutten, Marcel C. M.; van Sambeek, Marc R.; van de Vosse, Frans N.; Lopata, Richard G. P.

2017-04-01

Photoacoustic imaging (PAI) may have the ability to reveal the composition and the anatomical structure of carotid plaques, which determines its mechanical properties and vulnerability. We used PAI and plane wave ultrasound (PUS) imaging to obtain three-dimensional (3-D) images of endarterectomy samples ex vivo and compared the results with histology to investigate the potential of PAI-based identification of intraplaque hemorrhage. Seven carotid plaque samples were obtained from patients undergoing carotid endarterectomy and imaged with a fully integrated hand-held photoacoustic (PA) probe, consisting of a pulsed diode laser (tpulse=130 ns, Epulse=1 mJ, λ=808 nm) and a linear array transducer (fc=7.5 MHz). The samples were rotated 360 deg with 10 deg steps, and data were spatially compounded to obtain complete 3-D images of the plaques. Areas of high absorption in the 3-D datasets were identified and compared to histological data of the plaques. Data in six out of seven endarterectomy samples revealed the presence of intraplaque hemorrhages that were not visible in the PUS images. Due to the noninvasive nature of PAI, this ex vivo study may elucidate preclinical studies toward the in vivo, noninvasive, vulnerability assessment of the atherosclerotic carotid plaque.

Injectable visible light-cured glycol chitosan hydrogels with controlled release of anticancer drugs for local cancer therapy in vivo: a feasible study.

PubMed

Hyun, Hoon; Park, Min Ho; Lim, Wonbong; Kim, So Yeon; Jo, Danbi; Jung, Jin Seok; Jo, Gayoung; Um, Sewook; Lee, Deok-Won; Yang, Dae Hyeok

2018-05-11

Currently available chemotherapy is associated with serious side effects, and therefore novel drug delivery systems (DDSs) are required to specifically deliver anticancer drugs to targeted sites. In this study, we evaluated the feasibility of visible light-cured glycol chitosan (GC) hydrogels with controlled release of doxorubicin⋅hydrochloride (DOX⋅HCl) as local DDSs for effective cancer therapy in vivo. The storage modulus of the hydrogel precursor solutions was increased as a function of visible light irradiation time. In addition, the swelling ratio of the hydrogel irradiated for 10 s (GC 10 /DOX) was greater than in 60 s (GC 60 /DOX). In vitro release test showed that DOX was rapidly released in GC 10 /DOX compared with GC 60 /DOX due to the density of cross-linking. In vitro and in vivo tests including cell viability and measurement of tumor volume showed that the local treatment of GC 10 /DOX yielded substantially greater antitumor effect compared with that of GC 60 /DOX. Therefore, the visible light-cured GC hydrogel system may exhibit clinical potential as a local DDS of anticancer drugs with controlled release, by modulating cross-linking density.

A new approach for the delivery of artemisinin: formulation, characterization, and ex-vivo antileishmanial studies.

PubMed

Want, Muzamil Yaqub; Islamuddin, Mohammad; Chouhan, Garima; Dasgupta, Anjan Kumar; Chattopadhyay, Asoke Prasun; Afrin, Farhat

2014-10-15

Artemisinin, a potential antileishmanial compound with poor bioavailability and stability has limited efficacy in visceral leishmaniasis. Encapsulating artemisinin into poly lactic-co glycolic nanoparticles may improve its effectiveness and reduce toxicity. Artemisinin-loaded nanoparticles were prepared, optimized (using Box-Behnken design) and characterized by dynamic light scattering technique, Atomic force microscopy (AFM), Transmission electron microscopy (TEM) and Fourier Transform-Infra Red spectroscopy. Release kinetics of artemisinin from optimized nanoformulation was studied by dialysis method at pH 7.4 and 5.5. Cytotoxicity and antileishmanial activity of these nanoparticles was tested on murine macrophages by MTT assay and macrophage-infested Leishmania donovani amastigotes ex vivo, respectively. Artemisinin-loaded nanoparticles were 221±14nm in diameter, with polydispersity index, zeta potential, drug loading and entrapment efficiency of 0.1±0.015, -9.07±0.69mV, 28.03±1.14 and 68.48±1.97, respectively. AFM and TEM studies indicated that the particles were spherical in shape. These colloidal particles showed a sustained release pattern in vitro. Treatment with artemisinin-loaded nanoparticles significantly reduced the number of amastigotes per macrophage and percent infected macrophages ex vivo compared to free artemisinin. These nanoparticles were also non-toxic to macrophages compared to artemisinin alone. Copyright © 2014 Elsevier Inc. All rights reserved.

A potential model for drug screening by simulating the effect of shear stress in vivo on endothelium.

PubMed

Xu, Yingqian; Wang, Bochu; Deng, Jia; Liu, Zerong; Zhu, Liancai

2013-01-01

The purpose of this paper was to research the potential of a dynamic cell model in drug screening by studying the influence of microvascular wall shear stress on the drug absorption of endothelial cells compared to that in the static state. The cells were grown and seeded on gelatin-coated glass slides and were pretreated with extracts of Salviae miltiorrhizae (200 μg/ml) for 1 h. Then oxidative stress damage was produced by H2O2 (300 μmol/l) for 0.5 h under the 1.5 dyn/cm2 shear stress incorporated in a parallel plate flow chamber. Morphological analysis was conducted with an inverted microscope and image analysis software, and high performance liquid chromatography-mass spectrometry was used for the detection of active compounds. We compared the drug absorption in the dynamic group with that in the static group. In the dynamic model, five compounds and two new metabolite peaks were detected. However, in the static model, four compounds were absorbed by cells, and one metabolite peak was found. This study indicated that there were some effects on the absorption and metabolism of drugs under the microvascular shear stress compared to that under stasis. We infer that shear stress in the microcirculation situation in vivo played a role in causing the differences between drug screening in vitro and in vivo.

Sensitivity of Chemical Shift-Encoded Fat Quantification to Calibration of Fat MR Spectrum

PubMed Central

Wang, Xiaoke; Hernando, Diego; Reeder, Scott B.

2015-01-01

Purpose To evaluate the impact of different fat spectral models on proton density fat-fraction (PDFF) quantification using chemical shift-encoded (CSE) MRI. Material and Methods Simulations and in vivo imaging were performed. In a simulation study, spectral models of fat were compared pairwise. Comparison of magnitude fitting and mixed fitting was performed over a range of echo times and fat fractions. In vivo acquisitions from 41 patients were reconstructed using 7 published spectral models of fat. T2-corrected STEAM-MRS was used as reference. Results Simulations demonstrate that imperfectly calibrated spectral models of fat result in biases that depend on echo times and fat fraction. Mixed fitting is more robust against this bias than magnitude fitting. Multi-peak spectral models showed much smaller differences among themselves than when compared to the single-peak spectral model. In vivo studies show all multi-peak models agree better (for mixed fitting, slope ranged from 0.967–1.045 using linear regression) with reference standard than the single-peak model (for mixed fitting, slope=0.76). Conclusion It is essential to use a multi-peak fat model for accurate quantification of fat with CSE-MRI. Further, fat quantification techniques using multi-peak fat models are comparable and no specific choice of spectral model is shown to be superior to the rest. PMID:25845713

Reduction of quaternary ammonium-induced ocular surface toxicity by emulsions: an in vivo study in rabbits

PubMed Central

Liang, H.; Brignole-Baudouin, F.; Rabinovich-Guilatt, L.; Mao, Z.; Riancho, L.; Faure, M.O.; Warnet, J.M.; Lambert, G.

2008-01-01

Purpose To evaluate and compare the toxicological profiles of two quaternary ammonium compounds (QAC), benzalkonium chloride (BAK), and cetalkonium chloride (CKC), in standard solution or cationic emulsion formulations in rabbit eyes using newly developed in vivo and ex vivo experimental approaches. Methods Seventy eyes of 35 adult male New Zealand albino rabbits were used in this study. They were randomly divided into five groups: 50 µl of phosphate-buffered saline (PBS), PBS containing 0.02% BAK or 0.002% CKC (BAK Sol and CKC Sol, respectively), and emulsion containing 0.02% BAK or 0.002% CKC (BAK Em and CKC Em, respectively) were applied to rabbit eyes 15 times at 5-min intervals. The ocular surface changes induced by these eye drops were investigated using slit-lamp examination, flow cytometry (FCM), impression cytology (IC) on conjunctiva, and corneal in vivo confocal microscopy (IVCM). Standard immunohistology in cryosections was also examined for cluster of differentiation (CD) 45+ infiltrating and terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL)+ apoptotic cells. Results Clinical observations and IVCM showed that the highest toxicity was induced by BAK Sol, characterized by damaged corneal epithelium and a high level of inflammatory infiltration. BAK Em and CKC Sol presented moderate effects, and CKC Em showed the lowest toxicity with results similar to those of PBS. Conjunctival imprints analyzed by FCM showed a higher expression of RLA-DR and TNFR1 markers in BAK Sol-instilled eyes than in all other groups, especially at 4 h. Immunohistology was correlated with in vivo and ex vivo findings and confirmed this toxicity profile. A high level of infiltration of CD45+ inflammatory cells and TUNEL+ apoptotic cells was observed in limbus and conjunctiva, especially in QAC solution-receiving eyes compared to QAC emulsion-instilled eyes. Conclusions The acute administration of 15 instillations at 5 min intervals was a rapid and efficient model to assess quaternary ammonium toxicity profiles. This model showed the highest toxicity, induced by the BAK solution, and the lowest level of toxicity, induced by the CKC emulsion. These in vivo and ex vivo experimental approaches demonstrated that ocular surface toxicity was reduced by using an emulsion instead of a traditional solution and that a CKC emulsion was safe for future ocular administration. PMID:18347566

Reduction of quaternary ammonium-induced ocular surface toxicity by emulsions: an in vivo study in rabbits.

PubMed

Liang, H; Brignole-Baudouin, F; Rabinovich-Guilatt, L; Mao, Z; Riancho, L; Faure, M O; Warnet, J M; Lambert, G; Baudouin, C

2008-01-31

To evaluate and compare the toxicological profiles of two quaternary ammonium compounds (QAC), benzalkonium chloride (BAK), and cetalkonium chloride (CKC), in standard solution or cationic emulsion formulations in rabbit eyes using newly developed in vivo and ex vivo experimental approaches. Seventy eyes of 35 adult male New Zealand albino rabbits were used in this study. They were randomly divided into five groups: 50 microl of phosphate-buffered saline (PBS), PBS containing 0.02% BAK or 0.002% CKC (BAK Sol and CKC Sol, respectively), and emulsion containing 0.02% BAK or 0.002% CKC (BAK Em and CKC Em, respectively) were applied to rabbit eyes 15 times at 5-min intervals. The ocular surface changes induced by these eye drops were investigated using slit-lamp examination, flow cytometry (FCM), impression cytology (IC) on conjunctiva, and corneal in vivo confocal microscopy (IVCM). Standard immunohistology in cryosections was also examined for cluster of differentiation (CD) 45+ infiltrating and terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL)+ apoptotic cells. Clinical observations and IVCM showed that the highest toxicity was induced by BAK Sol, characterized by damaged corneal epithelium and a high level of inflammatory infiltration. BAK Em and CKC Sol presented moderate effects, and CKC Em showed the lowest toxicity with results similar to those of PBS. Conjunctival imprints analyzed by FCM showed a higher expression of RLA-DR and TNFR1 markers in BAK Sol-instilled eyes than in all other groups, especially at 4 h. Immunohistology was correlated with in vivo and ex vivo findings and confirmed this toxicity profile. A high level of infiltration of CD45+ inflammatory cells and TUNEL+ apoptotic cells was observed in limbus and conjunctiva, especially in QAC solution-receiving eyes compared to QAC emulsion-instilled eyes. The acute administration of 15 instillations at 5 min intervals was a rapid and efficient model to assess quaternary ammonium toxicity profiles. This model showed the highest toxicity, induced by the BAK solution, and the lowest level of toxicity, induced by the CKC emulsion. These in vivo and ex vivo experimental approaches demonstrated that ocular surface toxicity was reduced by using an emulsion instead of a traditional solution and that a CKC emulsion was safe for future ocular administration.

Underlying mechanism of drug-drug interaction between pioglitazone and gemfibrozil: Gemfibrozil acyl-glucuronide is a mechanism-based inhibitor of CYP2C8.

PubMed

Takagi, Motoi; Sakamoto, Masaya; Itoh, Tomoo; Fujiwara, Ryoichi

2015-08-01

While co-administered gemfibrozil can increase the area under the concentration/time curve (AUC) of pioglitazone more than 3-fold, the underlying mechanism of the drug-drug interaction between gemfibrozil and pioglitazone has not been fully understood. In the present study, gemfibrozil preincubation time-dependently inhibited the metabolism of pioglitazone in the cytochrome P450 (CYP)- and UDP-glucuronosyltransferase (UGT)-activated human liver microsomes. We estimated the kinact and K'app values, which are the maximum inactivation rate constant and the apparent dissociation constant, of gemfibrozil to be 0.071 min(-1) and 57.3 μM, respectively. In this study, the kobs, in vivo value was defined as a parameter that indicates the potency of the mechanism-based inhibitory effect at the blood drug concentration in vivo. The kobs, in vivo values of potent mechanism-based inhibitors, clarithromycin and erythromycin, were estimated to be 0.0096 min(-1) and 0.0051 min(-1), respectively. The kobs, in vivo value of gemfibrozil was 0.0060 min(-1), which was comparable to those of clarithromycin and erythromycin, suggesting that gemfibrozil could be a mechanism-based inhibitor as potent as clarithromycin and erythromycin in vivo. Copyright © 2015 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.

A primary cell model of HIV-1 latency that uses activation through the T cell receptor and return to quiescence to establish latent infection

PubMed Central

Kim, Michelle; Hosmane, Nina N.; Bullen, C. Korin; Capoferri, Adam; Yang, Hung-Chih; Siliciano, Janet D.; Siliciano, Robert F.

2015-01-01

A mechanistic understanding of HIV-1 latency depends upon a model system that recapitulates the in vivo condition of latently infected, resting CD4+ T lymphocytes. Latency appears to be established after activated CD4+ T cells, the principal targets of HIV-1 infection, become productively infected and survive long enough to return to a resting memory state in which viral expression is inhibited by changes in the cellular environment. This protocol describes an ex vivo primary cell system that is generated under conditions that reflect the in vivo establishment of latency. Creation of these latency model cells takes 12 weeks and, once established, the cells can be maintained and used for several months. The resulting cell population contains both uninfected and latently infected cells. This primary cell model can be used to perform drug screens, study CTL responses to HIV-1, compare viral alleles, or to expand the ex vivo lifespan of cells from HIV-1 infected individuals for extended study. PMID:25375990

Aspartame induces angiogenesis in vitro and in vivo models.

PubMed

Yesildal, F; Aydin, F N; Deveci, S; Tekin, S; Aydin, I; Mammadov, R; Fermanli, O; Avcu, F; Acikel, C H; Ozgurtas, T

2015-03-01

Angiogenesis is the process of generating new blood vessels from preexisting vessels and is considered essential in many pathological conditions. The purpose of the present study is to evaluate the effect of aspartame on angiogenesis in vivo chick chorioallantoic membrane (CAM) and wound-healing models as well as in vitro 2,3-bis-2H-tetrazolium-5-carboxanilide (XTT) and tube formation assays. In CAM assay, aspartame increased angiogenesis in a concentration-dependent manner. Compared with the control group, aspartame has significantly increased vessel proliferation (p < 0.001). In addition, in vivo rat model of skin wound-healing study showed that aspartame group had better healing than control group, and this was statistically significant at p < 0.05. There was a slight proliferative effect of aspartame on human umbilical vein endothelial cells on XTT assay in vitro, but it was not statistically significant; and there was no antiangiogenic effect of aspartame on tube formation assay in vitro. These results provide evidence that aspartame induces angiogenesis in vitro and in vivo; so regular use may have undesirable effect on susceptible cases. © The Author(s) 2015.

A. cantoniensis inhibits the proliferation of murine leukemia WEHI-3 cells in vivo and promotes immunoresponses in vivo.

PubMed

Tan, Tzu-Wei; Lin, Yuh-Tzy; Yang, Jai-Sing; Lu, Chi-Cheng; Chiang, Jo-Hua; Wu, Chang-Lin; Lin, Jing-Pin; Tang, Nou-Ying; Yeh, Chin-Chung; Fan, Ming-Jen; Chung, Jing-Gung

2009-01-01

Ampelopsis cantoniensis (AC) has been used as a folk medicine for reducing pain in the Taiwanese population. Our previous studies have shown that the crude extract of AC induced apoptosis in human promyelocytic leukemia HL-60 cells. In this study, the in vivo effects of AC on leukemia WEHI-3 cells and immune responses such as phagocytosis and natural killer (NK) cell activity were investigated. The weights of the livers and spleens were decreased in the AC-treated groups compared to the control groups. The AC treatment increased the percentage of CD3 and CD19 marker cells in WEHI-3-injected mice, indicating that the precursors of T and B cells were inhibited. The AC treatment promoted the activity of macrophage phagocytosis in the peripheral blood mononuclear cells (PBMC) and peritoneal cells. It was found that the NK cells from mice after treatment with AC can kill the YAC-1 target cells. Therefore, the AC treatment increased NK cell activity. In conclusion, AC can affect WEHI-3 cells in vivo and promote macrophage and NK cell activities.

Elastic Cherenkov effects in transversely isotropic soft materials-II: Ex vivo and in vivo experiments

NASA Astrophysics Data System (ADS)

Li, Guo-Yang; He, Qiong; Qian, Lin-Xue; Geng, Huiying; Liu, Yanlin; Yang, Xue-Yi; Luo, Jianwen; Cao, Yanping

2016-09-01

In part I of this study, we investigated the elastic Cherenkov effect (ECE) in an incompressible transversely isotropic (TI) soft solid using a combined theoretical and computational approach, based on which an inverse method has been proposed to measure both the anisotropic and hyperelastic parameters of TI soft tissues. In this part, experiments were carried out to validate the inverse method and demonstrate its usefulness in practical measurements. We first performed ex vivo experiments on bovine skeletal muscles. Not only the shear moduli along and perpendicular to the direction of muscle fibers but also the elastic modulus EL and hyperelastic parameter c2 were determined. We next carried out tensile tests to determine EL, which was compared with the value obtained using the shear wave elastography method. Furthermore, we conducted in vivo experiments on the biceps brachii and gastrocnemius muscles of ten healthy volunteers. To the best of our knowledge, this study represents the first attempt to determine EL of human muscles using the dynamic elastography method and inverse analysis. The significance of our method and its potential for clinical use are discussed.

Ex vivo permeation of carprofen from nanoparticles: A comprehensive study through human, porcine and bovine skin as anti-inflammatory agent.

PubMed

Parra, Alexander; Clares, Beatriz; Rosselló, Ana; Garduño-Ramírez, María L; Abrego, Guadalupe; García, María L; Calpena, Ana C

2016-03-30

The purpose of this study was the development of poly(d,l-lactide-co-glycolide) acid (PLGA) nanoparticles (NPs) for the dermal delivery of carprofen (CP). The developed nanovehicle was then lyophilized using hydroxypropyl-β-cyclodextrin (HPβCD) as cryoprotectant. The ex vivo permeation profiles were evaluated using Franz diffusion cells using three different types of skin membranes: human, porcine and bovine. Furthermore, biomechanical properties of skin (trans-epidermal water loss and skin hydration) were tested. Finally, the in vivo skin irritation and the anti-inflammatory efficacy were also assayed. Results demonstrated the achievement of NPs 187.32 nm sized with homogeneous distribution, negatively charged surface (-23.39 mV) and high CP entrapment efficiency (75.38%). Permeation studies showed similar diffusion values between human and porcine skins and higher for bovine. No signs of skin irritation were observed in rabbits. Topically applied NPs significantly decreased in vivo inflammation compared to the reference drug in a TPA-induced mouse ear edema model. Thus, it was concluded that NPs containing CP may be a useful tool for the dermal treatment of local inflammation. Copyright © 2016 Elsevier B.V. All rights reserved.

Rationally designed nanocarriers for intranasaltherapy of allergic rhinitis: influence of carrier type on in vivo nasal deposition

PubMed Central

Sallam, Marwa Ahmed; Helal, Hala Mahmoud; Mortada, Sana Mohamed

2016-01-01

The aim of this study is to develop a locally acting nasal delivery system of triamcinolone acetonide (TA) for the maintenance therapy of allergic rhinitis. The effect of encapsulating TA in different nanocarriers on its mucosal permeation and retention as well as in vivo nasal deposition has been studied. A comparative study was established between polymeric oil core nanocapsules (NCs), lipid nanocarriers such as nanoemulsion (NE), and nanostructured lipid carriers (NLCs). The elaborated nanocarriers were compared with TA suspension and the commercially available suspension “Nasacort®”. The study revealed that NC provided the highest mucosal retention, as 46.14%±0.048% of the TA initial dose was retained after 24 hours, while showing the least permeation through the nasal mucosa. On the other hand, for TA suspension and Nasacort®, the mucosal retention did not exceed 23.5%±0.047% of the initial dose after 24 hours. For NE and NLC, values of mucosal retention were 19.4%±0.041% and 10.97%±0.13%, respectively. NC also showed lower mucosal irritation and superior stability compared with NE. The in vivo nasal deposition study demonstrated that NC maintained drug in its site of action (nasal cavity mucosa) for the longest period of time. The elaborated polymeric oil core NCs are efficient carriers for the administration of nasally acting TA as it produced the least permeation results, thus decreasing systemic absorption of TA. Although NCs have been administered via various routes, this is the first study to implement the polymeric oil core NC as an efficient carrier for localized nasal drug delivery. PMID:27307734

Morphometric Analysis of Aqueous Humor Outflow Structures with Spectral-Domain Optical Coherence Tomography

PubMed Central

Francis, Andrew W.; Kagemann, Larry; Wollstein, Gadi; Ishikawa, Hiroshi; Folz, Steven; Overby, Darryl R.; Sigal, Ian A.; Wang, Bo; Schuman, Joel S.

2012-01-01

Purpose. To describe morphometric details of the human aqueous humor (AH) outflow microvasculature visualized with 360-degree virtual castings during active AH outflow in cadaver eyes and to compare these structures with corrosion casting studies. Methods. The conventional AH outflow pathways of donor eyes (n = 7) and eyes in vivo (n = 3) were imaged with spectral-domain optical coherence tomography (SD-OCT) and wide-bandwidth superluminescent diode array during active AH outflow. Digital image contrast was adjusted to isolate AH microvasculature, and images were viewed in a 3D viewer. Additional eyes (n = 3) were perfused with mock AH containing fluorescent tracer microspheres to compare microvasculature patterns. Results. Observations revealed components of the conventional outflow pathway from Schlemm's canal (SC) to the superficial intrascleral venous plexus (ISVP). The superficial ISVP in both our study and corrosion casts were composed of interconnected venules (10–50 μm) forming a hexagonal meshwork. Larger radial arcades (50–100 μm) drained the region nearest SC and converged with larger tortuous vessels (>100 μm). A 360-degree virtual casting closely approximated corrosion casting studies. Tracer studies corroborated our findings. Tracer decorated several larger vessels (50–100 μm) extending posteriorly from the limbus in both raw and contrast-enhanced fluorescence images. Smaller tracer-labeled vessels (30–40 μm) were seen branching between larger vessels and exhibited a similar hexagonal network pattern. Conclusions. SD-OCT is capable of detailed morphometric analysis of the conventional outflow pathway in vivo or ex vivo with details comparable to corrosion casting techniques. PMID:22499987

An ex vivo human skin model for studying skin barrier repair.

PubMed

Danso, Mogbekeloluwa O; Berkers, Tineke; Mieremet, Arnout; Hausil, Farzia; Bouwstra, Joke A

2015-01-01

In the studies described in this study, we introduce a novel ex vivo human skin barrier repair model. To develop this, we removed the upper layer of the skin, the stratum corneum (SC) by a reproducible cyanoacrylate stripping technique. After stripping the explants, they were cultured in vitro to allow the regeneration of the SC. We selected two culture temperatures 32 °C and 37 °C and a period of either 4 or 8 days. After 8 days of culture, the explant generated SC at a similar thickness compared to native human SC. At 37 °C, the early and late epidermal differentiation programmes were executed comparably to native human skin with the exception of the barrier protein involucrin. At 32 °C, early differentiation was delayed, but the terminal differentiation proteins were expressed as in stripped explants cultured at 37 °C. Regarding the barrier properties, the SC lateral lipid organization was mainly hexagonal in the regenerated SC, whereas the lipids in native human SC adopt a more dense orthorhombic organization. In addition, the ceramide levels were higher in the cultured explants at 32 °C and 37 °C than in native human SC. In conclusion, we selected the stripped ex vivo skin model cultured at 37 °C as a candidate model to study skin barrier repair because epidermal and SC characteristics mimic more closely the native human skin than the ex vivo skin model cultured at 32 °C. Potentially, this model can be used for testing formulations for skin barrier repair. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Natural Arctium lappa fruit extract improves the clinical signs of aging skin.

PubMed

Knott, Anja; Reuschlein, Katja; Mielke, Heiko; Wensorra, Ursula; Mummert, Christopher; Koop, Urte; Kausch, Martina; Kolbe, Ludger; Peters, Nils; Stäb, Franz; Wenck, Horst; Gallinat, Stefan

2008-12-01

Subclinical, chronic tissue inflammation involving the generation of cytokines (e.g., interleukin-6 and tumor necrosis factor-alpha) might contribute to the cutaneous aging process. This study aims to screen for an active ingredient with anti-inflammatory (i.e., reduction of interleukin-6 and tumor necrosis factor-alpha) and matrix-stimulating efficacy which improves the clinical signs of skin aging in vivo. In vitro studies with pure Arctiin were performed investigating the inhibition of cytokine induction and stimulation of collagen neo-synthesis. In vivo home-in-use studies using an Arctium lappa fruit extract-containing formulation were carried out to determine procollagen and hyaluronan synthesis, hyaluronan synthase-2 gene expression, and reduction of wrinkle volume after treatment. In vitro studies on human dermal fibroblasts and monocyte-derived dendritic cells supplemented with pure Arctiin showed relative to untreated control cells a stimulation of collagen synthesis and a decrease in interleukin-6 and tumor necrosis factor-alpha concentration, respectively. In addition, topical in vivo application of an A. lappa fruit extract-containing formulation for 12 weeks significantly stimulated procollagen synthesis and increased hyaluronan synthase-2 expression as well as hyaluronan levels compared to vehicle-treated control areas. Similarly, after a 4-week treatment with an A. lappa fruit extract-containing formulation, wrinkle volume in the crow's feet area was significantly reduced as compared to treatment with the vehicle. Our data show that topical treatment with a natural A. lappa fruit extract significantly improves the metabolism of the dermal extracellular matrix and leads to a visible wrinkle reduction in vivo. In conclusion, A. lappa fruit extract represents a targeted means to regenerate dermal structures and, thus, offers an effective treatment option for mature skin.

Swept source optical coherence tomography for in vivo growth monitoring of capsicum annuum seeds treated with different NaCl concentrations

NASA Astrophysics Data System (ADS)

Ravichandran, Naresh Kumar; Wijesinghe, Ruchire Eranga; Lee, Seung-Yeol; Shirazi, Muhammad Faizan; Park, Kibeom; Jung, Hee-Young; Jeon, Mansik; Kim, Jeehyun

2017-04-01

In this study, Optical coherence tomography (OCT) is demonstrated as a plausible optical tool for in vivo detection of plant seeds and its morphological changes during growth. The experiment was carried out on Capsicum annuum seeds that were treated with different molar concentrations of NaCl to investigate the most optimal concentration for the seed growth. The monitoring process was carried out for 9 consecutive days. The in vivo 2D OCT images of the treated seeds were obtained and compared with seeds that were grown with sterile distilled water. The obtained results confirm the feasibility of using OCT for the proposed application. Normalized A-scan analysis method is utilized for supporting the concluded results.

Validating in vivo Raman spectroscopy of bone in human subjects

NASA Astrophysics Data System (ADS)

Esmonde-White, Francis W. L.; Morris, Michael D.

2013-03-01

Raman spectroscopy can non-destructively measure properties of bone related to mineral density, mineral composition, and collagen composition. Bone properties can be measured through the skin in animal and human subjects, but correlations between the transcutaneous and exposed bone measurements have only been reported for human cadavers. In this study, we examine human subjects to collect measurements transcutaneously, on surgically exposed bone, and on recovered bone fragments. This data will be used to demonstrate in vivo feasibility and to compare transcutaneous and exposed Raman spectroscopy of bone. A commercially available Raman spectrograph and optical probe operating at 785 nm excitation are used for the in vivo measurements. Requirements for applying Raman spectroscopy during a surgery are also discussed.

Microbleed and microinfarct detection in amyloid angiopathy: a high-resolution MRI-histopathology study

PubMed Central

van Veluw, Susanne J.; Charidimou, Andreas; van der Kouwe, Andre J.; Lauer, Arne; Reijmer, Yael D.; Costantino, Isabel; Gurol, M. Edip; Biessels, Geert Jan; Frosch, Matthew P.; Viswanathan, Anand; Greenberg, Steven M.

2016-01-01

Cerebral amyloid angiopathy is a common neuropathological finding in the ageing human brain, associated with cognitive impairment. Neuroimaging markers of severe cerebral amyloid angiopathy are cortical microbleeds and microinfarcts. These parenchymal brain lesions are considered key contributors to cognitive impairment. Therefore, they are important targets for therapeutic strategies and may serve as surrogate neuroimaging markers in clinical trials. We aimed to gain more insight into the pathological basis of magnetic resonance imaging-defined microbleeds and microinfarcts in cerebral amyloid angiopathy, and to explore the pathological burden that remains undetected, by using high and ultra-high resolution ex vivo magnetic resonance imaging, as well as detailed histological sampling. Brain samples from five cases (mean age 85 ± 6 years) with pathology-proven cerebral amyloid angiopathy and multiple microbleeds on in vivo clinical magnetic resonance imaging were subjected to high-resolution ex vivo 7 T magnetic resonance imaging. On the obtained high-resolution (200 μm isotropic voxels) ex vivo magnetic resonance images, 171 microbleeds were detected compared to 66 microbleeds on the corresponding in vivo magnetic resonance images. Of 13 sampled microbleeds that were matched on histology, five proved to be acute and eight old microhaemorrhages. The iron-positive old microhaemorrhages appeared approximately four times larger on magnetic resonance imaging compared to their size on histology. In addition, 48 microinfarcts were observed on ex vivo magnetic resonance imaging in three out of five cases (two cases exhibited no microinfarcts). None of them were visible on in vivo 1.5 T magnetic resonance imaging after a retrospective analysis. Of nine sampled microinfarcts that were matched on histology, five were confirmed as acute and four as old microinfarcts. Finally, we explored the proportion of microhaemorrhage and microinfarct burden that is beyond the detection limits of ex vivo magnetic resonance imaging, by scanning a smaller sample at ultra-high resolution, followed by serial sectioning. At ultra-high resolution (75 μm isotropic voxels) magnetic resonance imaging we observed an additional 48 microbleeds (compared to high resolution), which proved to correspond to vasculopathic changes (i.e. morphological changes to the small vessels) instead of frank haemorrhages on histology. After assessing the serial sections of this particular sample, no additional haemorrhages were observed that were missed on magnetic resonance imaging. In contrast, nine microinfarcts were found in these sections, of which six were only retrospectively visible at ultra-high resolution. In conclusion, these findings suggest that microbleeds on in vivo magnetic resonance imaging are specific for microhaemorrhages in cerebral amyloid angiopathy, and that increasing the resolution of magnetic resonance images results in the detection of more ‘non-haemorrhagic’ pathology. In contrast, the vast majority of microinfarcts currently remain under the detection limits of clinical in vivo magnetic resonance imaging. PMID:27645801

Divergent Requirement of Fc-Fcγ Receptor Interactions for In Vivo Protection against Influenza Viruses by Two Pan-H5 Hemagglutinin Antibodies

PubMed Central

Wang, Shuangshuang; Ren, Huanhuan; Jiang, Wenbo; Chen, Honglin; Hu, Hongxing; Chen, Zhiwei

2017-01-01

ABSTRACT Recent studies have shown that Fc-Fcγ receptor (FcγR) interactions are required for in vivo protection against influenza viruses by broadly reactive anti-hemagglutinin (HA) stem, but not virus strain-specific, anti-receptor binding site (RBS), antibodies (Abs). Since only a few Abs recognizing epitopes in the head region but outside the RBS have been tested against single-challenge virus strains, it remains unknown whether Fc-FcγR interactions are required for in vivo protection by Abs recognizing epitopes outside the RBS and whether the requirement is virus strain specific or epitope specific. In the present study, we therefore investigated the requirements for in vivo protection using two pan-H5 Abs, 65C6 and 100F4. We generated chimeric Abs, 65C6/IgG2a and 100F4/IgG2a, which preferentially engage activating FcγRs, and isogenic forms, 65C6/D265A and 100F4/D265A, which do not bind FcγR. Virus neutralizing activity, binding, antibody-dependent cellular cytotoxicity (ADCC), and in vivo protection of these Abs were compared using three H5 strains, A/Shenzhen/406H/2006 (SZ06), A/chicken/Shanxi/2/2006 (SX06), and A/chicken/Netherlands/14015526/2014 (NE14). We found that all four chimeric Abs bound and neutralized the SZ06 and NE14 strains but poorly inhibited the SX06 strain. 65C6/IgG2a and 100F4/IgG2a, but not 65C6/D265A and 100F4/D265A, mediated ADCC against target cells expressing HA derived from all three virus strains. Interestingly, both 65C6/IgG2a and 65C6/D265A demonstrated comparable protection against all three virus strains in vivo; however, 100F4/IgG2a, but not 100F4/D265A, showed in vivo protection. Thus, we conclude that Fc-FcγR interactions are required for in vivo protection by 100F4, but not by 65C6, and therefore, protection is not virus strain specific but epitope specific. IMPORTANCE Abs play an important role in immune protection against influenza virus infection. Fc-FcγR interactions are required for in vivo protection by broadly neutralizing antistem, but not by virus strain-specific, anti-receptor binding site (RBS), Abs. Whether such interactions are necessary for protection by Abs that recognize epitopes outside RBS is not fully understood. In the present study, we investigated in vivo protection mechanisms against three H5 strains by two pan-H5 Abs, 65C6 and 100F4. We show that although these two Abs have similar neutralizing, binding, and ADCC activities against all three H5 strains in vitro, they have divergent requirements for Fc-FcγR interactions to protect against the three H5 strains in vivo. The Fc-FcγR interactions are required for in vivo protection by 100F4, but not by 65C6. Thus, we conclude that Fc-FcγR interactions for in vivo protection by pan-H5 Abs is not strain specific, but epitope specific. PMID:28331095

Divergent Requirement of Fc-Fcγ Receptor Interactions for In Vivo Protection against Influenza Viruses by Two Pan-H5 Hemagglutinin Antibodies.

PubMed

Wang, Shuangshuang; Ren, Huanhuan; Jiang, Wenbo; Chen, Honglin; Hu, Hongxing; Chen, Zhiwei; Zhou, Paul

2017-06-01

Recent studies have shown that Fc-Fcγ receptor (FcγR) interactions are required for in vivo protection against influenza viruses by broadly reactive anti-hemagglutinin (HA) stem, but not virus strain-specific, anti-receptor binding site (RBS), antibodies (Abs). Since only a few Abs recognizing epitopes in the head region but outside the RBS have been tested against single-challenge virus strains, it remains unknown whether Fc-FcγR interactions are required for in vivo protection by Abs recognizing epitopes outside the RBS and whether the requirement is virus strain specific or epitope specific. In the present study, we therefore investigated the requirements for in vivo protection using two pan-H5 Abs, 65C6 and 100F4. We generated chimeric Abs, 65C6/IgG2a and 100F4/IgG2a, which preferentially engage activating FcγRs, and isogenic forms, 65C6/D265A and 100F4/D265A, which do not bind FcγR. Virus neutralizing activity, binding, antibody-dependent cellular cytotoxicity (ADCC), and in vivo protection of these Abs were compared using three H5 strains, A/Shenzhen/406H/2006 (SZ06), A/chicken/Shanxi/2/2006 (SX06), and A/chicken/Netherlands/14015526/2014 (NE14). We found that all four chimeric Abs bound and neutralized the SZ06 and NE14 strains but poorly inhibited the SX06 strain. 65C6/IgG2a and 100F4/IgG2a, but not 65C6/D265A and 100F4/D265A, mediated ADCC against target cells expressing HA derived from all three virus strains. Interestingly, both 65C6/IgG2a and 65C6/D265A demonstrated comparable protection against all three virus strains in vivo ; however, 100F4/IgG2a, but not 100F4/D265A, showed in vivo protection. Thus, we conclude that Fc-FcγR interactions are required for in vivo protection by 100F4, but not by 65C6, and therefore, protection is not virus strain specific but epitope specific. IMPORTANCE Abs play an important role in immune protection against influenza virus infection. Fc-FcγR interactions are required for in vivo protection by broadly neutralizing antistem, but not by virus strain-specific, anti-receptor binding site (RBS), Abs. Whether such interactions are necessary for protection by Abs that recognize epitopes outside RBS is not fully understood. In the present study, we investigated in vivo protection mechanisms against three H5 strains by two pan-H5 Abs, 65C6 and 100F4. We show that although these two Abs have similar neutralizing, binding, and ADCC activities against all three H5 strains in vitro , they have divergent requirements for Fc-FcγR interactions to protect against the three H5 strains in vivo The Fc-FcγR interactions are required for in vivo protection by 100F4, but not by 65C6. Thus, we conclude that Fc-FcγR interactions for in vivo protection by pan-H5 Abs is not strain specific, but epitope specific. Copyright © 2017 American Society for Microbiology.

In vivo Candida glabrata biofilm development on foreign bodies in a rat subcutaneous model.

PubMed

Kucharíková, Soňa; Neirinck, Bram; Sharma, Nidhi; Vleugels, Jef; Lagrou, Katrien; Van Dijck, Patrick

2015-03-01

Biofilm studies have been mostly dedicated to the major human fungal pathogen Candida albicans, whereas much less is known about this virulence factor in Candida glabrata, certainly under in vivo conditions. This study provides a deeper understanding of the biofilm development of C. glabrata, its architecture and susceptibility profile to fluconazole and echinocandins. In vitro and in vivo C. glabrata biofilms were developed inside serum-coated triple-lumen catheters placed in 24-well polystyrene plates or implanted subcutaneously in the back of a rat, respectively. Scanning electron microscopy and confocal scanning laser microscopy were used to visualize the biofilm architecture. Quantitative real-time PCR was used to demonstrate the expression profile of EPA1, EPA3, EPA6 and AWP1-AWP7 during in vivo biofilm formation. Mature biofilms were observed within the first 48 h and the amount of biofilm reached its maximum by 6 days. Architecturally, mature C. glabrata biofilms consisted of a thick network of yeast cells embedded in an extracellular matrix. Moreover, in vivo biofilms were susceptible to echinocandin drugs, whereas fluconazole remained ineffective. Gene expression profiling revealed that EPA3, EPA6, AWP2, AWP3 and AWP5 were up-regulated in in vivo biofilms compared with in vitro biofilms. C. glabrata is a unique microorganism, which, despite the lack of transition to the hyphal form, formed thick biofilms inside foreign bodies in vivo. To our knowledge, this is the first study that has described in vivo C. glabrata biofilm development and its architectural changes in detail and provides an insight into the susceptibility profile, as well as the gene expression machinery, of biofilm-associated infections. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Tantalum oxide and barium sulfate as radiopacifiers in injectable calcium phosphate-poly(lactic-co-glycolic acid) cements for monitoring in vivo degradation.

PubMed

Hoekstra, Jan Willem M; van den Beucken, Jeroen J J P; Leeuwenburgh, Sander C G; Bronkhorst, Ewald M; Meijer, Gert J; Jansen, John A

2014-01-01

Monitoring the degradation of calcium phosphate-based bone substitute materials in vivo by means of noninvasive techniques (e.g., radiography) is often a problem due to the chemical resemblance of those substitutes with the mineral phase of bone. In the view of that, the present study aimed at enhancing the radiopacity of calcium phosphate cement enriched with poly(lactic-co-glycolic acid) (CPC-PLGA) microspheres, by adding tantalum oxide (Ta2O5) or the more traditional radiopacifier barium sulfate (BaSO4). The radiopacifying capacity of these radiopacifiers was first evaluated in vitro by microcomputed tomography (μCT). Thereafter, both radiopacifiers were tested in vivo using a distal femoral condyle model in rabbits, with subsequent ex vivo μCT analysis in parallel with histomorphometry. Addition of either one of the radiopacifiers proved to enhance radiopacity of CPC-PLGA in vitro. The in vivo experiment showed that both radiopacifiers did not induce alterations in biological performance compared to plain CPC-PLGA, hence both radiopacifiers can be considered safe and biocompatible. The histomorphometrical assessment of cement degradation and bone formation showed similar values for the three experimental groups. Interestingly, μCT analysis showed that monitoring cement degradation becomes feasible upon incorporation of either type of radiopacifier, albeit that BaSO4 showed more accuracy compared to Ta2O5. Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.

Comparison of optical projection tomography and optical coherence tomography for assessment of murine embryonic development

NASA Astrophysics Data System (ADS)

Singh, Manmohan; Nair, Achuth; Vadakkan, Tegy; Piazza, Victor; Udan, Ryan; Frazier, Michael V.; Janecek, Trevor; Dickinson, Mary E.; Larin, Kirill V.

2015-03-01

The murine model is a common model for studying developmental diseases. In this study, we compare the performance of the relatively new method of Optical Projection Tomography (OPT) to the well-established technique of Optical Coherence Tomography (OCT) to assess murine embryonic development at three stages, 9.5, 11.5, and 13.5 days post conception. While both methods can provide spatial resolution at the micrometer scale, OPT can provide superior imaging depth compared to OCT. However, OPT requires samples to be fixed, placed in an immobilization media such as agar, and cleared before imaging. Because OCT does not require fixing, it can be used to image embryos in vivo and in utero. In this study, we compare the efficacy of OPT and OCT for imaging murine embryonic development. The data demonstrate the superior capability of OPT for imaging fine structures with high resolution in optically-cleared embryos while only OCT can provide structural and functional imaging of live embryos ex vivo and in utero with micrometer scale resolution.

Poly(2-ethyl-2-oxazoline) conjugates with doxorubicin for cancer therapy: In vitro and in vivo evaluation and direct comparison to poly[N-(2-hydroxypropyl)methacrylamide] analogues.

PubMed

Sedlacek, Ondrej; Monnery, Bryn D; Mattova, Jana; Kucka, Jan; Panek, Jiri; Janouskova, Olga; Hocherl, Anita; Verbraeken, Bart; Vergaelen, Maarten; Zadinova, Marie; Hoogenboom, Richard; Hruby, Martin

2017-11-01

We designed and synthesized a new delivery system for the anticancer drug doxorubicin based on a biocompatible hydrophilic poly(2-ethyl-2-oxazoline) (PEtOx) carrier with linear architecture and narrow molar mass distribution. The drug is connected to the polymer backbone via an acid-sensitive hydrazone linker, which allows its triggered release in the tumor. The in vitro studies demonstrate successful cellular uptake of conjugates followed by release of the cytostatic cargo. In vivo experiments in EL4 lymphoma bearing mice revealed prolonged blood circulation, increased tumor accumulation and enhanced antitumor efficacy of the PEtOx conjugate having higher molecular weight (40 kDa) compared to the lower molecular weight (20 kDa) polymer. Finally, the in vitro and in vivo anti-cancer properties of the prepared PEtOx conjugates were critically compared with those of the analogous system based on the well-established PHPMA carrier. Despite the relatively slower intracellular uptake of PEtOx conjugates, resulting also in their lower cytotoxicity, there are no substantial differences in in vivo biodistribution and anti-cancer efficacy of both classes of polymer-Dox conjugates. Considering the synthetic advantages of poly(2-alkyl-2-oxazoline)s, the presented study demonstrates their potential as a versatile alternative to well-known PEO- or PHPMA-based materials for construction of drug delivery systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

The effect of formulation additives on in vitro dissolution-absorption profile and in vivo bioavailability of telmisartan from brand and generic formulations.

PubMed

Borbás, Enikő; Nagy, Zsombor K; Nagy, Brigitta; Balogh, Attila; Farkas, Balázs; Tsinman, Oksana; Tsinman, Konstantin; Sinkó, Bálint

2018-03-01

In this study, brand and four generic formulations of telmisartan, an antihypertensive drug, were used in in vitro simultaneous dissolution-absorption, investigating the effect of different formulation additives on dissolution and on absorption through an artificial membrane. The in vitro test was found to be sensitive enough to show even small differences between brand and generic formulations caused by the use of different excipients. By only changing the type of filler from sorbitol to mannitol in the formulation, the flux through the membrane was reduced by approximately 10%. Changing the salt forming agent as well resulted in approximately 20% of flux reduction compared to the brand formulation. This significant difference was clearly shown in the published in vivo results as well. The use of additional lactose monohydrate in the formulation also leads to approximately 10% reduction in flux. The results show that by changing excipients, the dissolution of telmisartan was not altered significantly, but the flux through the membrane was found to be significantly changed. These results pointed out the limitations of traditional USP dissolution tests and emphasized the importance of simultaneously measuring dissolution and absorption, which allows the complex effect of formulation excipients on both processes to be measured. Moreover, the in vivo predictive power of the simultaneous dissolution-absorption test was demonstrated by comparing the in vitro fluxes to in vivo bioequivalence study results. Copyright © 2018 Elsevier B.V. All rights reserved.

Assessment of sperm nuclear quality after in vitro maturation of fresh or frozen/thawed mouse pre-pubertal testes.

PubMed

Oblette, A; Rives, N; Dumont, L; Rives, A; Verhaeghe, F; Jumeau, F; Rondanino, C

2017-10-01

Is nuclear quality of in vitro generated spermatozoa from fresh or frozen/thawed pre-pubertal mouse testes similar to that of their in vivo counterparts? The production of spermatozoa with aneuploidy, DNA fragmentation or chromatin condensation defects was not significantly increased in organotypic cultures compared to in vivo controls. Although murine spermatozoa have been produced in vitro from pre-pubertal testes, their nuclear DNA integrity has never been investigated. Fresh and frozen/thawed testicular fragments from 6 to 7 days postpartum (dpp) mice were cultured for 30 days. Testicular tissues were frozen by controlled slow freezing (CSF) or solid surface vitrification (SSV). In total, 30 fresh, 30 CSF, 30 SSV testes were used for in vitro maturation and 6 testes from 36 to 37 dpp mice were used as in vivo controls. Murine spermatozoa were extracted from pooled in vitro cultured testicular fragments and from in vivo controls. Sperm aneuploidy was analyzed by fluorescence in situ hybridization (FISH), DNA fragmentation by terminal deoxynucleotidyl transferase mediated dUTP nick end labeling, chromatin condensation by aniline blue staining, telomere length and number by quantitative FISH, DNA oxidation by immunocytochemical detection of 8-hydroxy-2'-deoxyguanosine (8-OHdG). Because of the low spermatogenic yield in cultures, a hundred spermatozoa extracted from pooled tissues were examined and compared to their in vivo counterparts. Most of spermatozoa generated in vitro and in vivo were haploid, contained unfragmented DNA and normally condensed chromatin. A similar proportion of spermatozoa with aneuploidy, DNA fragmentation or chromatin condensation defects was found in cultures and in vivo. No significant difference in telomere length was found within the nuclei of in vitro and in vivo generated spermatozoa. However, the number of telomere spots was lower in gametes obtained from cultures of fresh, CSF and SSV testes than in their natural counterparts (P < 0.01). Moreover, the proportion of spermatozoa containing 8-OHdG was significantly increased in frozen/thawed tissues in comparison to fresh tissues and in vivo controls (P < 0.05). None. Further studies will be needed to enhance the production of spermatozoa in organotypic cultures while preserving their quality, to investigate epigenetic modifications and embryonic development. This is the first study comparing the nuclear quality of in vitro and in vivo generated murine spermatozoa. The organotypic culture system will have to be adapted for human tissue and extensive analyses of human gamete quality will have to be performed before potential clinical applications can be envisaged. This work was supported by Rouen University Hospital, Ligue contre le Cancer, Agence de la Biomédecine, Association Laurette Fugain, France Lymphome Espoir, and co-supported by European Union and Région Normandie. Europe gets involved in Normandie with European Régional Development Fund (ERDF). The authors declare that they have no conflict of interest. © The Author 2017. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email:journals.permissions@oup.com

Rejuvenation of allogenic red cells: benefits and risks.

PubMed

Aujla, H; Woźniak, M; Kumar, T; Murphy, G J

2018-06-04

To review preclinical and clinical studies that have evaluated the effects of red cell rejuvenation in vivo and in vitro and to assess the potential risks and benefits from their clinical use. A systematic review and narrative synthesis of the intervention of red cell rejuvenation using a red cell processing solution containing inosine, pyruvate, phosphate and adenine. Outcomes of interest in vitro were changes in red cell characteristics including adenosine triphosphate (ATP), 2,3-diphosphoglycerate (2,3-DPG), deformability and the accumulation of oxidized lipids and other reactive species in the red cell supernatant. Outcomes in vivo were 24-h post-transfusion survival and the effects on oxygen delivery, organ function and inflammation in transfused recipients. The literature search identified 49 studies evaluating rejuvenated red cells. In vitro rejuvenation restored cellular properties including 2,3-DPG and ATP to levels similar to freshly donated red cells. In experimental models, in vivo transfusion of rejuvenated red cells improved oxygen delivery and myocardial, renal and pulmonary function when compared to stored red cells. In humans, in vivo 24-h survival of rejuvenated red cells exceeded 75%. In clinical studies, rejuvenated red cells were found to be safe, with no reported adverse effects. In one adult cardiac surgery trial, transfusion of rejuvenated red cells resulted in improved myocardial performance. Transfusion of rejuvenated red cells reduces organ injury attributable to the red cell storage lesion without adverse effects in experimental studies in vivo. The clinical benefits of this intervention remain uncertain. © 2018 International Society of Blood Transfusion.

Preparation and evaluation of niosome gel containing acyclovir for enhanced dermal deposition.

PubMed

Jacob, Shery; Nair, Anroop B; Al-Dhubiab, Bandar E

2017-12-01

Niosomes suggest a versatile vesicle delivery system with possible transport of drugs via topical route for skin delivery. The aim of the present research was to optimize niosome gel formulation of acyclovir and to evaluate in both in vitro and in vivo rabbit model. Niosome formulations were formulated by coacervation phase separation technique with different ratios of nonionic surfactants, phospholipids and cholesterol using 3 2 factorial design. Altering the surfactant concentration has influenced the drug entrapment, but not vesicle size. At high surfactant combinations, the acyclovir release from niosomes was strongly influenced by cholesterol:lecithin ratio. Ex vivo drug permeation data indicate substantial difference in flux values and was influenced by the niosome composition. Ex vivo studies using formulation (B 8 ) for drug deposition indicate greater amount of niosome being diffused into the skin layers and formed a depot, compared to commercial acyclovir cream (control). Two distinct dermatopharmacokinetic profiles were observed, in vivo, for niosome gel formulation (B 8 ) and control, which were analog to the profiles observed with ex vivo deposition studies. In vivo plasma drug level suggests low systemic exposure of acyclovir (C max : 9.44 ± 2.27 ng/mL and 14.54 ± 3.11 ng/mL for niosome formulation and control, respectively). Comparison of kinetic data of acyclovir in the stratum corneum and plasma signifies that the niosome formulation forms a depot in the epidermis or dermis region. This study concludes that the niosome gel formulation (B 8 ) could be a viable vesicular system for an impressive transdermal delivery of acyclovir by topical application.

'En face' ex vivo reflectance confocal microscopy to help the surgery of basal cell carcinoma of the eyelid.

PubMed

Espinasse, Marine; Cinotti, Elisa; Grivet, Damien; Labeille, Bruno; Prade, Virginie; Douchet, Catherine; Cambazard, Frédéric; Thuret, Gilles; Gain, Philippe; Perrot, Jean Luc

2017-07-01

Ex vivo confocal microscopy is a recent imaging technique for the perioperative control of skin tumour margins. Up to date, it has been used in the fluorescence mode and with vertical sections of the specimen margins. The aim of this study was to evaluate its use in the reflectance mode and with a horizontal ('en face') scanning of the surgical specimen in a series of basal cell carcinoma of the eyelid. Prospective consecutive cohort study was performed at the University Hospital of Saint-Etienne, France. Forty-one patients with 42 basal cell carcinoma of the eyelid participated in this study. Basal cell carcinomas were excised with a 2-mm-wide clinically safe margin. The surgical specimens were analysed under ex vivo confocal microscopy in the reflectance mode and with an en face scanning in order to control at a microscopic level if the margins were free from tumour invasion. Histopathogical examination was later performed in order to compare the results. Sensitivity and specificity of ex vivo confocal microscopy for the presence of tumour-free margins. Ex vivo confocal microscopy results were consistent with histopathology in all cases (tumour-free margins in 40 out of 42 samples; sensitivity and specificity of 100%). Ex vivo confocal microscopy in the reflectance mode with an 'en face' scanning can control tumour margins of eyelid basal cell carcinomas and optimize their surgical management. This procedure has the advantage on the fluorescent mode of not needing any contrast agent to examine the samples. © 2016 Royal Australian and New Zealand College of Ophthalmologists.

Octreotide exerts different effects in vivo and in vitro in Cushing's disease.

PubMed

Stalla, G K; Brockmeier, S J; Renner, U; Newton, C; Buchfelder, M; Stalla, J; Müller, O A

1994-02-01

The effect of the long-acting somatostatin analog octreotide (SMS 201-995) on adrenocorticotropin (ACTH) secretion was studied in five patients with untreated Cushing's disease in vivo and in six human corticotropic adenoma cell cultures in vitro. For the in vivo study, 100 micrograms of octreotide sc was given 30 and 180 min after cannulation of the cubital vein and 100 micrograms of corticotropin-releasing hormone (CRH) was injected iv at 210 min. Serum ACTH and cortisol levels were measured for 390 min. In vivo, octreotide had no significant effect either on basal or CRH-stimulated ACTH levels and did not influence cortisol levels. The in vitro studies were conducted with corticotropic adenoma cell cultures derived from adenoma tissue obtained from six patients with Cushing's disease. In four of six cell cultures, octreotide (1 nmol/l-1 mumol/l) inhibited basal ACTH secretion in a dose-dependent manner. The inhibition ranged from 70 to 92% for 1 nmol/l octreotide to 14-46% for 1 mumol/l octreotide as compared to controls (100%). In three of three octreotide-responsive adenoma cell cultures investigated. CRH-stimulated ACTH secretion was suppressed by octreotide. Hydrocortisone pretreatment in vitro abolished the inhibitory effect of octreotide on ACTH secretion in one octreotide-responsive corticotropic adenoma cell culture. In conclusion, we showed that octreotide in most cases could inhibit the ACTH release from human corticotropic adenoma cells in vitro but had no suppressive effect on ACTH levels of patients with Cushing's disease in vivo. This discrepancy could be due to a somatostatin receptor down-regulation by cortisol at the hypercortisolemic state in vivo.

Prolonged Dye Release from Mesoporous Silica-Based Imaging Probes Facilitates Long-Term Optical Tracking of Cell Populations In Vivo.

PubMed

Rosenholm, Jessica M; Gulin-Sarfraz, Tina; Mamaeva, Veronika; Niemi, Rasmus; Özliseli, Ezgi; Desai, Diti; Antfolk, Daniel; von Haartman, Eva; Lindberg, Desiré; Prabhakar, Neeraj; Näreoja, Tuomas; Sahlgren, Cecilia

2016-03-23

Nanomedicine is gaining ground worldwide in therapy and diagnostics. Novel nanoscopic imaging probes serve as imaging tools for studying dynamic biological processes in vitro and in vivo. To allow detectability in the physiological environment, the nanostructure-based probes need to be either inherently detectable by biomedical imaging techniques, or serve as carriers for existing imaging agents. In this study, the potential of mesoporous silica nanoparticles carrying commercially available fluorochromes as self-regenerating cell labels for long-term cellular tracking is investigated. The particle surface is organically modified for enhanced cellular uptake, the fluorescence intensity of labeled cells is followed over time both in vitro and in vivo. The particles are not exocytosed and particles which escaped cells due to cell injury or death are degraded and no labeling of nontargeted cell populations are observed. The labeling efficiency is significantly improved as compared to that of quantum dots of similar emission wavelength. Labeled human breast cancer cells are xenotransplanted in nude mice, and the fluorescent cells can be detected in vivo for a period of 1 month. Moreover, ex vivo analysis reveals fluorescently labeled metastatic colonies in lymph node and rib, highlighting the capability of the developed probes for tracking of metastasis. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Modifying the affective behavior of preschoolers with autism using in-vivo or video modeling and reinforcement contingencies.

PubMed

Gena, Angeliki; Couloura, Sophia; Kymissis, Effie

2005-10-01

The purpose of this study was to modify the affective behavior of three preschoolers with autism in home settings and in the context of play activities, and to compare the effects of video modeling to the effects of in-vivo modeling in teaching these children contextually appropriate affective responses. A multiple-baseline design across subjects, with a return to baseline condition, was used to assess the effects of treatment that consisted of reinforcement, video modeling, in-vivo modeling, and prompting. During training trials, reinforcement in the form of verbal praise and tokens was delivered contingent upon appropriate affective responding. Error correction procedures differed for each treatment condition. In the in-vivo modeling condition, the therapist used modeling and verbal prompting. In the video modeling condition, video segments of a peer modeling the correct response and verbal prompting by the therapist were used as corrective procedures. Participants received treatment in three categories of affective behavior--sympathy, appreciation, and disapproval--and were presented with a total of 140 different scenarios. The study demonstrated that both treatments--video modeling and in-vivo modeling--systematically increased appropriate affective responding in all response categories for the three participants. Additionally, treatment effects generalized across responses to untrained scenarios, the child's mother, new therapists, and time.

Effect of Microenvironment on Differentiation of Human Umbilical Cord Mesenchymal Stem Cells into Hepatocytes In Vitro and In Vivo

PubMed Central

Xue, Gai; Han, Xiaolei; Ma, Xin; Wu, Honghai; Qin, Yabin; Liu, Jianfang; Hu, Yuqin; Hong, Yang; Hou, Yanning

2016-01-01

Human umbilical cord-derived mesenchymal stem cells (hUCMSCs) are considered to be an ideal cell source for cell therapy of many diseases. The aim of this study was to investigate the contribution of the microenvironment to the hepatic differentiation potential of hUCMSCs in vitro and in vivo and to explore their therapeutic use in acute liver injury in rats. We established a new model to simulate the liver tissue microenvironment in vivo using liver homogenate supernatant (LHS) in vitro. This induced environment could drive hUCMSCs to differentiate into hepatocyte-like cells within 7 days. The differentiated cells expressed hepatocyte-specific markers and demonstrated hepatocellular functions. We also injected hUCMSCs into rats with CCl4-induced acute hepatic injury. The hUCMSCs were detected in the livers of recipient rats and expressed the human hepatocyte-specific markers, suggesting that hUCMSCs could differentiate into hepatocyte-like cells in vivo in the liver tissue microenvironment. Levels of biochemistry markers improved significantly after transplantation of hUCMSCs compared with the nontransplantation group (P < 0.05). In conclusion, this study demonstrated that the liver tissue microenvironment may contribute to the differentiation of hUCMSCs into hepatocytes both in vitro and in vivo. PMID:27088093

Detecting bacterial lung infections: in vivo evaluation of in vitro volatile fingerprints.

PubMed

Zhu, Jiangjiang; Bean, Heather D; Wargo, Matthew J; Leclair, Laurie W; Hill, Jane E

2013-03-01

The identification of bacteria by their volatilomes is of interest to many scientists and clinicians as it holds the promise of diagnosing infections in situ, particularly lung infections via breath analysis. While there are many studies reporting various bacterial volatile biomarkers or fingerprints using in vitro experiments, it has proven difficult to translate these data to in vivo breath analyses. Therefore, we aimed to create secondary electrospray ionization-mass spectrometry (SESI-MS) pathogen fingerprints directly from the breath of mice with lung infections. In this study we demonstrated that SESI-MS is capable of differentiating infected versus uninfected mice, P. aeruginosa-infected versus S. aureus-infected mice, as well as distinguish between infections caused by P. aeruginosa strains PAO1 versus FRD1, with statistical significance (p < 0.05). In addition, we compared in vitro and in vivo volatiles and observed that only 25-34% of peaks are shared between the in vitro and in vivo SESI-MS fingerprints. To the best of our knowledge, these are the first breath volatiles measured for P. aeruginosa PAO1, FRD1, and S. aureus RN450, and the first comparison of in vivo and in vitro volatile profiles from the same strains using the murine infection model.

A High-Resolution Enhancer Atlas of the Developing Telencephalon

PubMed Central

Visel, Axel; Taher, Leila; Girgis, Hani; May, Dalit; Golonzhka, Olga; Hoch, Renee; McKinsey, Gabriel L.; Pattabiraman, Kartik; Silberberg, Shanni N.; Blow, Matthew J.; Hansen, David V.; Nord, Alex S.; Akiyama, Jennifer A.; Holt, Amy; Hosseini, Roya; Phouanenavong, Sengthavy; Plajzer-Frick, Ingrid; Shoukry, Malak; Afzal, Veena; Kaplan, Tommy; Kriegstein, Arnold R.; Rubin, Edward M.; Ovcharenko, Ivan; Pennacchio, Len A.; Rubenstein, John L. R.

2013-01-01

Summary The mammalian telencephalon plays critical roles in cognition, motor function, and emotion. While many of the genes required for its development have been identified, the distant-acting regulatory sequences orchestrating their in vivo expression are mostly unknown. Here we describe a digital atlas of in vivo enhancers active in subregions of the developing telencephalon. We identified over 4,600 candidate embryonic forebrain enhancers and studied the in vivo activity of 329 of these sequences in transgenic mouse embryos. We generated serial sets of histological brain sections for 145 reproducible forebrain enhancers, resulting in a publicly accessible web-based data collection comprising over 32,000 sections. We also used epigenomic analysis of human and mouse cortex tissue to directly compare the genome-wide enhancer architecture in these species. These data provide a primary resource for investigating gene regulatory mechanisms of telencephalon development and enable studies of the role of distant-acting enhancers in neurodevelopmental disorders. PMID:23375746

In vivo monitoring of nicotine biosynthesis in tobacco leaves by low-temperature plasma mass spectrometry.

PubMed

Martínez-Jarquín, Sandra; Herrera-Ubaldo, Humberto; de Folter, Stefan; Winkler, Robert

2018-08-01

Low-temperature plasma (LTP) is capable of ionizing a broad range of organic molecules at ambient conditions. The coupling of LTP to a mass analyzer delivers chemical profiles from delicate objects. To investigate the suitability of LTP ionization for mass spectrometry (MS) based in vivo studies, we monitored the auxin-regulated nicotine biosynthesis in tobacco (Nicotiana tabacum) and evaluated possible biological effects. The measured nicotine concentrations in different experiments were comparable to literature data obtained with conventional methods. The observed compounds suggest the rupture of trichomes, and cell damage was observed on the spots exposed to LTP. However, the lesions only affected a negligible proportion of the leaf surface area and no systemic reaction was noted. Thus, our study provides the proof-of-concept for measuring the biosynthetic activity of plant surfaces in vivo. Copyright © 2018 Elsevier B.V. All rights reserved.

Correlation of In Vivo Versus In Vitro Benchmark Doses (BMDs) Derived From Micronucleus Test Data: A Proof of Concept Study.

PubMed

Soeteman-Hernández, Lya G; Fellows, Mick D; Johnson, George E; Slob, Wout

2015-12-01

In this study, we explored the applicability of using in vitro micronucleus (MN) data from human lymphoblastoid TK6 cells to derive in vivo genotoxicity potency information. Nineteen chemicals covering a broad spectrum of genotoxic modes of action were tested in an in vitro MN test using TK6 cells using the same study protocol. Several of these chemicals were considered to need metabolic activation, and these were administered in the presence of S9. The Benchmark dose (BMD) approach was applied using the dose-response modeling program PROAST to estimate the genotoxic potency from the in vitro data. The resulting in vitro BMDs were compared with previously derived BMDs from in vivo MN and carcinogenicity studies. A proportional correlation was observed between the BMDs from the in vitro MN and the BMDs from the in vivo MN assays. Further, a clear correlation was found between the BMDs from in vitro MN and the associated BMDs for malignant tumors. Although these results are based on only 19 compounds, they show that genotoxicity potencies estimated from in vitro tests may result in useful information regarding in vivo genotoxic potency, as well as expected cancer potency. Extension of the number of compounds and further investigation of metabolic activation (S9) and of other toxicokinetic factors would be needed to validate our initial conclusions. However, this initial work suggests that this approach could be used for in vitro to in vivo extrapolations which would support the reduction of animals used in research (3Rs: replacement, reduction, and refinement). © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology.

Accounting for data variability, a key factor in in vivo/in vitro relationships: application to the skin sensitization potency (in vivo LLNA versus in vitro DPRA) example.

PubMed

Dimitrov, S; Detroyer, A; Piroird, C; Gomes, C; Eilstein, J; Pauloin, T; Kuseva, C; Ivanova, H; Popova, I; Karakolev, Y; Ringeissen, S; Mekenyan, O

2016-12-01

When searching for alternative methods to animal testing, confidently rescaling an in vitro result to the corresponding in vivo classification is still a challenging problem. Although one of the most important factors affecting good correlation is sample characteristics, they are very rarely integrated into correlation studies. Usually, in these studies, it is implicitly assumed that both compared values are error-free numbers, which they are not. In this work, we propose a general methodology to analyze and integrate data variability and thus confidence estimation when rescaling from one test to another. The methodology is demonstrated through the case study of rescaling the in vitro Direct Peptide Reactivity Assay (DPRA) reactivity to the in vivo Local Lymph Node Assay (LLNA) skin sensitization potency classifications. In a first step, a comprehensive statistical analysis evaluating the reliability and variability of LLNA and DPRA as such was done. These results allowed us to link the concept of gray zones and confidence probability, which in turn represents a new perspective for a more precise knowledge of the classification of chemicals within their in vivo OR in vitro test. Next, the novelty and practical value of our methodology introducing variability into the threshold optimization between the in vitro AND in vivo test resides in the fact that it attributes a confidence probability to the predicted classification. The methodology, classification and screening approach presented in this study are not restricted to skin sensitization only. They could be helpful also for fate, toxicity and health hazard assessment where plenty of in vitro and in chemico assays and/or QSARs models are available. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Mechanism of age-dependent involution in embryonic chick notochords.

PubMed

Ghanem, E; Cornelissen, M; Thierens, H; De Ridder, L

1996-07-15

To study the possible mechanism of the age-dependent involution of the notochord, isolated mesenchyme-free notochords of chick embryos were cultured in vitro and compared with their counterparts in vivo. Two different aspects were evaluated: (1) DNA synthesis measured by [3H]thymidine incorporation and visualized by autoradiography and (2) cell death quantified by counting the number of pyknotic nuclei. The results demonstrate that [3H]thymidine uptake by notochords shows an age-dependent decrease in vitro as well as in vivo. The number of [3H]thymidine-labelled notochord cells, however, is higher in vitro than in vivo. At the same time, there is an age-dependent increase in pyknosis in the notochord in vivo and in vitro. So, during the aging process, the number of both pyknotic nuclei and of [3H]thymidine-labelled nuclei suggest a high turnover of notochord cells in vitro. From these results, we can conclude that the process of involution in aging notochord seems to be controlled by a programmed intrinsic process, which might be influenced partially by the microenvironment in vivo.

Effect of mono-(2-ethylhexyl) phthalate on human and mouse fetal testis: In vitro and in vivo approaches

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muczynski, V.; CEA, DSV, iRCM, SCSR, LDRG, 92265 Fontenay-aux-Roses; INSERM, Unité 967, F-92265, Fontenay aux Roses

The present study was conducted to determine whether exposure to the mono-(2-ethylhexyl) phthalate (MEHP) represents a genuine threat to male human reproductive function. To this aim, we investigated the effects on human male fetal germ cells of a 10{sup −5} M exposure. This dose is slightly above the mean concentrations found in human fetal cord blood samples by biomonitoring studies. The in vitro experimental approach was further validated for phthalate toxicity assessment by comparing the effects of in vitro and in vivo exposure in mouse testes. Human fetal testes were recovered during the first trimester (7–12 weeks) of gestation andmore » cultured in the presence or not of 10{sup −5} M MEHP for three days. Apoptosis was quantified by measuring the percentage of Caspase-3 positive germ cells. The concentration of phthalate reaching the fetal gonads was determined by radioactivity measurements, after incubations with {sup 14}C-MEHP. A 10{sup −5} M exposure significantly increased the rate of apoptosis in human male fetal germ cells. The intratesticular MEHP concentration measured corresponded to the concentration added in vitro to the culture medium. Furthermore, a comparable effect on germ cell apoptosis in mouse fetal testes was induced both in vitro and in vivo. This study suggests that this 10{sup −5} M exposure is sufficient to induce changes to the in vivo development of the human fetal male germ cells. -- Highlights: ► 10{sup −5} M of MEHP impairs germ cell development in the human fetal testis. ► Organotypic culture is a suitable approach to investigate phthalate effects in human. ► MEHP is not metabolized in the human fetal testis. ► In mice, MEHP triggers similar effects both in vivo and in vitro.« less

GLPG0492, a novel selective androgen receptor modulator, improves muscle performance in the exercised-mdx mouse model of muscular dystrophy.

PubMed

Cozzoli, Anna; Capogrosso, Roberta Francesca; Sblendorio, Valeriana Teresa; Dinardo, Maria Maddalena; Jagerschmidt, Catherine; Namour, Florence; Camerino, Giulia Maria; De Luca, Annamaria

2013-06-01

Anabolic drugs may counteract muscle wasting and dysfunction in Duchenne muscular dystrophy (DMD); however, steroids have unwanted side effects. We focused on GLPG0492, a new non-steroidal selective androgen receptor modulator that is currently under development for musculo-skeletal diseases such as sarcopenia and cachexia. GLPG0492 was tested in the exercised mdx mouse model of DMD in a 4-week trial at a single high dose (30 mg/kg, 6 day/week s.c.), and the results were compared with those from the administration of α-methylprednisolone (PDN; 1 mg/kg, i.p.) and nandrolone (NAND, 5 mg/kg, s.c.). This assessment was followed by a 12-week dose-dependence study (0.3-30 mg/kg s.c.). The outcomes were evaluated in vivo and ex vivo on functional, histological and biochemical parameters. Similar to PDN and NAND, GLPG0492 significantly increased mouse strength. In acute exhaustion tests, a surrogate of the 6-min walking test used in DMD patients, GLPG0492 preserved running performance, whereas vehicle- or comparator-treated animals showed a significant increase in fatigue (30-50%). Ex vivo, all drugs resulted in a modest but significant increase of diaphragm force. In parallel, a decrease in the non-muscle area and markers of fibrosis was observed in GLPG0492- and NAND-treated mice. The drugs exerted minor effects on limb muscles; however, electrophysiological biomarkers were ameliorated in extensor digitorum longus muscle. The longer dose-dependence study confirmed the effect on mdx mouse strength and resistance to fatigue and demonstrated the efficacy of lower drug doses on in vivo and ex vivo functional parameters. These results support the interest of further studies of GLPG0492 as a potential treatment for DMD. Copyright © 2013 Elsevier Ltd. All rights reserved.

mRNA expression pattern of selected candidate genes differs in bovine oviductal epithelial cells in vitro compared with the in vivo state and during cell culture passages.

PubMed

Danesh Mesgaran, Sadjad; Sharbati, Jutta; Einspanier, Ralf; Gabler, Christoph

2016-08-15

The mammalian oviduct provides the optimal environment for gamete maturation including sperm capacitation, fertilization, and development of the early embryo. Various cell culture models for primary bovine oviductal epithelial cells (BOEC) were established to reveal such physiological events. The aim of this study was to evaluate 17 candidate mRNA expression patterns in oviductal epithelial cells (1) in transition from in vivo cells to in vitro cells; (2) during three consecutive cell culture passages; (3) affected by the impact of LOW or HIGH glucose content media; and (4) influenced by different phases of the estrous cycle in vivo and in vitro. In addition, the release of a metabolite and proteins from BOEC at two distinct cell culture passage numbers was estimated to monitor the functionality. BOEC from 8 animals were isolated and cultured for three consecutive passages. Total RNA was extracted from in vivo and in vitro samples and subjected to reverse transcription quantitative polymerase chain reaction to reveal mRNA expression of selected candidate genes. The release of prostaglandin E2 (PGE2), oviduct-specific glycoprotein 1 (OVGP1) and interleukin 8 (IL8) by BOEC was measured by EIA or ELISA after 24 h. Almost all candidate genes (prostaglandin synthases, enzymes of cellular metabolism and mucins) mRNA expression pattern differed compared in vivo with in vitro state. In addition, transcription of most candidate genes was influenced by the number of cell culture passages. Different glucose medium content did not affect mRNA expression of most candidate genes. The phase of the estrous cycle altered some candidate mRNA expression in BOEC in vitro at later passages. The release of PGE2 and OVGP1 between passages did not differ. However, BOEC in passage 3 released significantly higher amount of IL8 compared with cells in passage 0. This study supports the hypothesis that candidate mRNA expression in BOEC was influenced by transition from the in vivo situation to the new in vitro environment and during consecutive passages. The consequence of cell culture passaging on BOEC ability to release bioactive compounds should be considered.

Activated Platelets in Carotid Artery Thrombosis in Mice Can Be Selectively Targeted with a Radiolabeled Single-Chain Antibody

PubMed Central

Goldschmidt, Jürgen; Pethe, Annette; Hagemeyer, Christoph E.; Neudorfer, Irene; Zirlik, Andreas; Weber, Wolfgang A.; Bode, Christoph; Meyer, Philipp T.

2011-01-01

Background Activated platelets can be found on the surface of inflamed, rupture-prone and ruptured plaques as well as in intravascular thrombosis. They are key players in thrombosis and atherosclerosis. In this study we describe the construction of a radiolabeled single-chain antibody targeting the LIBS-epitope of activated platelets to selectively depict platelet activation and wall-adherent non-occlusive thrombosis in a mouse model with nuclear imaging using in vitro and ex vivo autoradiography as well as small animal SPECT-CT for in vivo analysis. Methodology/Principal Findings LIBS as well as an unspecific control single-chain antibody were labeled with 111Indium (111In) via bifunctional DTPA ( = 111In-LIBS/111In-control). Autoradiography after incubation with 111In-LIBS on activated platelets in vitro (mean 3866±28 DLU/mm2, 4010±630 DLU/mm2 and 4520±293 DLU/mm2) produced a significantly higher ligand uptake compared to 111In-control (2101±76 DLU/mm2, 1181±96 DLU/mm2 and 1866±246 DLU/mm2) indicating a specific binding to activated platelets; P<0.05. Applying these findings to an ex vivo mouse model of carotid artery thrombosis revealed a significant increase in ligand uptake after injection of 111In-LIBS in the presence of small thrombi compared to the non-injured side, as confirmed by histology (49630±10650 DLU/mm2 vs. 17390±7470 DLU/mm2; P<0.05). These findings could also be reproduced in vivo. SPECT-CT analysis of the injured carotid artery with 111In-LIBS resulted in a significant increase of the target-to-background ratio compared to 111In-control (1.99±0.36 vs. 1.1±0.24; P<0.01). Conclusions/Significance Nuclear imaging with 111In-LIBS allows the detection of platelet activation in vitro and ex vivo with high sensitivity. Using SPECT-CT, wall-adherent activated platelets in carotid arteries could be depicted in vivo. These results encourage further studies elucidating the role of activated platelets in plaque pathology and atherosclerosis and might be of interest for further developments towards clinical application. PMID:21479193

Mesenchymal stem cell characteristics of dental pulp and periodontal ligament stem cells after in vivo transplantation.

PubMed

Lei, Ming; Li, Kun; Li, Bei; Gao, Li-Na; Chen, Fa-Ming; Jin, Yan

2014-08-01

Mesenchymal stem cells (MSCs) isolated from human postnatal dental pulp and periodontal ligament (PDL) tissues can give rise to multilineage differentiation in vitro and generate related dental tissues in vivo. However, the cell properties of human dental pulp stem cells (DPSCs) and PDL stem cells (PDLSCs) after in vivo implantation remain largely unidentified. In this study, cells were re-isolated from in vivo-generated dental pulp-like and PDL-like tissues (termed re-DPCs and re-PDLCs, respectively) as a result of ectopic transplantation of human DPSC and PDLSC sheets. The cell characteristics in terms of colony-forming ability, cell surface antigens and multi-differentiation potentials were all evaluated before and after implantation. It was found that re-DPCs and re-PDLCs were of human and mesenchymal origin and positive for MSC markers such as STRO-1, CD146, CD29, CD90 and CD105; and, to some extent, re-DPCs could maintain their colony forming abilities. Moreover, both cell types were able to form mineral deposits and differentiate into adipocytes and chondrocytes; however, quantitative analysis and related gene expression determination showed that the osteo-/chondro-differentiation capabilities of re-DPCs and re-PDLCs were significantly reduced compared to those of DPSCs and PDLSCs, respectively (P < 0.05); re-PDLCs showed a greater reduction potential than re-DPCs. We conclude that DPSCs and PDLSCs may maintain their MSC characteristics after in vivo implantation and, compared to PDLSCs, DPSCs appear much more stable under in vivo conditions. These findings provide additional cellular and molecular evidence that supports expanding the use of dental tissue-derived stem cells in cell therapy and tissue engineering. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Ex Vivo Eye Irritation Test as an alternative test method for serious eye damage/eye irritation.

PubMed

Spöler, Felix; Kray, Oya; Kray, Stefan; Panfil, Claudia; Schrage, Norbert F

2015-07-01

Ocular irritation testing is a common requirement for the classification, labelling and packaging of chemicals (substances and mixtures). The in vivo Draize rabbit eye test (OECD Test Guideline 405) is considered to be the regulatory reference method for the classification of chemicals according to their potential to induce eye injury. In the Draize test, chemicals are applied to rabbit eyes in vivo, and changes are monitored over time. If no damage is observed, the chemical is not categorised. Otherwise, the classification depends on the severity and reversibility of the damage. Alternative test methods have to be designed to match the classifications from the in vivo reference method. However, observation of damage reversibility is usually not possible in vitro. Within the present study, a new organotypic method based on rabbit corneas obtained from food production is demonstrated to close this gap. The Ex Vivo Eye Irritation Test (EVEIT) retains the full biochemical activity of the corneal epithelium, epithelial stem cells and endothelium. This permits the in-depth analysis of ocular chemical trauma beyond that achievable by using established in vitro methods. In particular, the EVEIT is the first test to permit the direct monitoring of recovery of all corneal layers after damage. To develop a prediction model for the EVEIT that is comparable to the GHS system, 37 reference chemicals were analysed. The experimental data were used to derive a three-level potency ranking of eye irritation and corrosion that best fits the GHS categorisation. In vivo data available in the literature were used for comparison. When compared with GHS classification predictions, the overall accuracy of the three-level potency ranking was 78%. The classification of chemicals as irritating versus non-irritating resulted in 96% sensitivity, 91% specificity and 95% accuracy. 2015 FRAME.

Homeostatic effects of exercise and sleep on metabolic processes in mice with an overexpressed skeletal muscle clock.

PubMed

Brager, Allison J; Heemstra, Lydia; Bhambra, Raman; Ehlen, J Christopher; Esser, Karyn A; Paul, Ketema N; Novak, Colleen M

2017-01-01

Brain and muscle-ARNT-like factor (Bmal1/BMAL1) is an essential transcriptional/translational factor of circadian clocks. Loss of function of Bmal1/BMAL1 is highly disruptive to physiological and behavioral processes. In light of these previous findings, we examined if transgenic overexpression of Bmal1/BMAL1 in skeletal muscle could alter metabolic processes. First, we characterized in vivo and ex vivo metabolic phenotypes of muscle overexpressed mice (male and female) compared to wild-type littermates (WT). Second, we examined in vivo and ex vivo metabolic processes in the presence of positive and negative homeostatic challenges: high-intensity treadmill running (positive) and acute sleep deprivation (negative). In vivo measures of metabolic processes included body composition, respiratory exchange ratio (RER; VCO 2 /VO 2 ), energy expenditure, total activity counts, and food intake collected from small animal indirect calorimetry. Ex vivo measure of insulin sensitivity in skeletal muscle was determined from radioassays. RER was lower for muscle overexpressed females compared to female WTs. There were no genotype-dependent differences in metabolic phenotypes for males. With homeostatic challenges, muscle overexpressed mice had lower energy expenditure after high-intensity treadmill running. Acute sleep deprivation reduced insulin sensitivity in skeletal muscle in overexpressed male mice, but not male WTs. The present study contributes to a body of evidence showing pleiotropic, non-circadian, and homeostatic effects of altered Bmal1/BMAL1 expression on metabolic processes, demonstrating a critical need to further investigate the broad and complex actions of Bmal1/BMAL1 on physiology and behavior. Published by Elsevier B.V.

Effects of DETANONOate, a nitric oxide donor, on hemostasis in rabbits: an in vitro and in vivo thrombelastographic analysis.

PubMed

Nielsen, V G; Geary, B T; Baird, M S

2000-03-01

The purpose of this study was to determine if whole blood thrombelastographic variables (reaction time, K, alpha, and maximum amplitude) would be adversely effected by exposure to the nitric oxide (NO) donor, DETANONOate, in vitro or after alveolar instillation in vivo. Conscious rabbits (n = 10) had blood sampled from ear arteries anticoagulated with sodium citrate. The blood was then incubated with 0, 1, 5, 10, or 20 mmol/L DETANONOate for 30 minutes. Arterial blood from anesthetized rabbits (n = 4) was obtained and anticoagulated before and 60 minutes after 1 mmol/L DETANONOate (2 mL/kg) was instilled into the right lung. After incubation, all samples were placed in a thrombelastograph and recalcified, with thrombelastographic variables measured for 45 minutes. In vitro, 10 mmol/L DETANONOate significantly (P < .05) increased reaction time, K, and decreased alpha compared with values observed after incubation with 0, 1, and 5 mmol/L DETANONOate. Twenty mmol/L DETANONOate significantly (P < .05) increased reaction time, K, and decreased alpha and maximum amplitude values compared with all other concentrations. In vivo, DETANONOate administration did not significantly affect thrombelastographic variables. DETANONOate significantly decreased hemostatic function in vitro in a dose-dependent fashion but did not significantly affect hemostatic function in vivo.

A comparative study of the chondrogenic potential between synthetic and natural scaffolds in an in vivo bioreactor

NASA Astrophysics Data System (ADS)

Huang, Jung-Ju; Yang, Shu-Rui; Chu, I.-Ming; Brey, Eric M.; Hsiao, Hui-Yi; Cheng, Ming-Huei

2013-10-01

The clinical demand for cartilage tissue engineering is potentially large for reconstruction defects resulting from congenital deformities or degenerative disease due to limited donor sites for autologous tissue and donor site morbidities. Cartilage tissue engineering has been successfully applied to the medical field: a scaffold pre-cultured with chondrocytes was used prior to implantation in an animal model. We have developed a surgical approach in which tissues are engineered by implantation with a vascular pedicle as an in vivo bioreactor in bone and adipose tissue engineering. Collagen type II, chitosan, poly(lactic-co-glycolic acid) (PLGA) and polycaprolactone (PCL) were four commonly applied scaffolds in cartilage tissue engineering. To expand the application of the same animal model in cartilage tissue engineering, these four scaffolds were selected and compared for their ability to generate cartilage with chondrocytes in the same model with an in vivo bioreactor. Gene expression and immunohistochemistry staining methods were used to evaluate the chondrogenesis and osteogenesis of specimens. The result showed that the PLGA and PCL scaffolds exhibited better chondrogenesis than chitosan and type II collagen in the in vivo bioreactor. Among these four scaffolds, the PCL scaffold presented the most significant result of chondrogenesis embedded around the vascular pedicle in the long-term culture incubation phase.

Comparative Proteomic Analysis of Human Liver Tissue and Isolated Hepatocytes with a Focus on Proteins Determining Drug Exposure.

PubMed

Vildhede, Anna; Wiśniewski, Jacek R; Norén, Agneta; Karlgren, Maria; Artursson, Per

2015-08-07

Freshly isolated human hepatocytes are considered the gold standard for in vitro studies of liver functions, including drug transport, metabolism, and toxicity. For accurate predictions of the in vivo outcome, the isolated hepatocytes should reflect the phenotype of their in vivo counterpart, i.e., hepatocytes in human liver tissue. Here, we quantified and compared the membrane proteomes of freshly isolated hepatocytes and human liver tissue using a label-free shotgun proteomics approach. A total of 5144 unique proteins were identified, spanning over 6 orders of magnitude in abundance. There was a good global correlation in protein abundance. However, the expression of many plasma membrane proteins was lower in the isolated hepatocytes than in the liver tissue. This included transport proteins that determine hepatocyte exposure to many drugs and endogenous compounds. Pathway analysis of the differentially expressed proteins confirmed that hepatocytes are exposed to oxidative stress during isolation and suggested that plasma membrane proteins were degraded via the protein ubiquitination pathway. Finally, using pitavastatin as an example, we show how protein quantifications can improve in vitro predictions of in vivo liver clearance. We tentatively conclude that our data set will be a useful resource for improved hepatocyte predictions of the in vivo outcome.

Mutagenicity testing with transgenic mice. Part II: Comparison with the mouse spot test

PubMed Central

Wahnschaffe, Ulrich; Bitsch, Annette; Kielhorn, Janet; Mangelsdorf, Inge

2005-01-01

The mouse spot test, an in vivo mutation assay, has been used to assess a number of chemicals. It is at present the only in vivo mammalian test system capable of detecting somatic gene mutations according to OECD guidelines (OECD guideline 484). It is however rather insensitive, animal consuming and expensive type of test. More recently several assays using transgenic animals have been developed. From data in the literature, the present study compares the results of in vivo testing of over twenty chemicals using the mouse spot test and compares them with results from the two transgenic mouse models with the best data base available, the lacI model (commercially available as the Big Blue® mouse), and the lacZ model (commercially available as the Muta™ Mouse). There was agreement in the results from the majority of substances. No differences were found in the predictability of the transgenic animal assays and the mouse spot test for carcinogenicity. However, from the limited data available, it seems that the transgenic mouse assay has several advantages over the mouse spot test and may be a suitable test system replacing the mouse spot test for detection of gene but not chromosome mutations in vivo. PMID:15676065

Spectral Remittance and Transmittance of Visible and Infrared-A Radiation in Human Skin-Comparison Between in vivo Measurements and Model Calculations.

PubMed

Piazena, Helmut; Meffert, Hans; Uebelhack, Ralf

2017-11-01

The aim of the study was to assess the interindividual variability of spectral remittance and spectral transmittance of visible and infrared-A radiations interacting with human skin and subcutaneous tissue, and direct measurements were taken in vivo using healthy persons of different skin color types. Up to wavelengths of about 900 nm, both spectral remittance and spectral transmittance depended significantly on the individual contents of melanin and hemoglobin in the skin, whereas the contents of water and lipids mainly determined spectral slopes of both characteristics of interaction for wavelengths above about 900 nm. In vivo measured data of spectral transmittance showed approximately similar decreases with tissue thickness between about 900 nm and 1100 nm as compared with model data which were calculated using spectral absorption and scattering coefficients of skin samples in vitro published by different authors. In addition, in vivo measured data and in vitro-based model calculations of spectral remittance were approximately comparable in this wavelength range. In contrast, systematic but individually varying differences between both methods were found for both spectral remittance and spectral transmittance at wavelengths below about 900 nm, where interaction of radiation was significantly affected by both melanin and hemoglobin. © 2017 The American Society of Photobiology.

The practical approach to the evaluation of methods used to determine the disintegration time of orally disintegrating tablets (ODTs)

PubMed Central

Brniak, Witold; Jachowicz, Renata; Pelka, Przemyslaw

2015-01-01

Even that orodispersible tablets (ODTs) have been successfully used in therapy for more than 20 years, there is still no compendial method of their disintegration time evaluation other than the pharmacopoeial disintegration test conducted in 800–900 mL of distilled water. Therefore, several alternative tests more relevant to in vivo conditions were described by different researchers. The aim of this study was to compare these methods and correlate them with in vivo results. Six series of ODTs were prepared by direct compression. Their mechanical properties and disintegration times were measured with pharmacopoeial and alternative methods and compared with the in vivo results. The highest correlation with oral disintegration time was found in the case of own-construction apparatus with additional weight and the employment of the method proposed by Narazaki et al. The correlation coefficients were 0.9994 (p < 0.001), and 0.9907 (p < 0.001) respectively. The pharmacopoeial method correlated with the in vivo data much worse (r = 0.8925, p < 0.05). These results have shown that development of novel biorelevant methods of ODT’s disintegration time determination is eligible and scientifically justified. PMID:27134547

Lecithin-coated gold nanoflowers (GNFs) for CT scan imaging applications and biochemical parameters; in vitro and in vivo studies.

PubMed

Aziz, Farooq; Bano, Khizra; Siddique, Ahmad Hassan; Bajwa, Sadia Zafar; Nazir, Aalia; Munawar, Anam; Shaheen, Ayesha; Saeed, Madiha; Afzal, Muhammad; Iqbal, M Zubair; Wu, Aiguo; Khan, Waheed S

2018-01-09

We report a novel strategy for the fabrication of lecithin-coated gold nanoflowers (GNFs) via single-step design for CT imaging application. Field-emission electron microscope confirmed flowers like morphology of the as-synthesized nanostructures. Furthermore, these show absorption peak in near-infrared (NIR) region at λ max 690 nm Different concentrations of GNFs are tested as a contrast agent in CT scans at tube voltage 135 kV and tube current 350 mA. These results are compared with same amount of iodine at same CT scan parameters. The results of in vitro CT scan study show that GNFs have good contrast enhancement properties, whereas in vivo study of rabbits CT scan shows that GNFs enhance the CT image clearly at 135 kV as compared to that of iodine. Cytotoxicity was studied and blood profile show minor increase of white blood cells and haemoglobin, whereas decrease of red blood cells and platelets.

Targeted Imaging of the Atypical Chemokine Receptor 3 (ACKR3/CXCR7) in Human Cancer Xenografts.

PubMed

Behnam Azad, Babak; Lisok, Ala; Chatterjee, Samit; Poirier, John T; Pullambhatla, Mrudula; Luker, Gary D; Pomper, Martin G; Nimmagadda, Sridhar

2016-06-01

The atypical chemokine receptor ACKR3 (formerly CXCR7), overexpressed in various cancers compared with normal tissues, plays a pivotal role in adhesion, angiogenesis, tumorigenesis, metastasis, and tumor cell survival. ACKR3 modulates the tumor microenvironment and regulates tumor growth. The therapeutic potential of ACKR3 has also been demonstrated in various murine models of human cancer. Literature findings underscore the importance of ACKR3 in disease progression and suggest it as an important diagnostic marker for noninvasive imaging of ACKR3-overexpressing malignancies. There are currently no reports on direct receptor-specific detection of ACKR3 expression. Here we report the evaluation of a radiolabeled ACKR3-targeted monoclonal antibody (ACKR3-mAb) for the noninvasive in vivo nuclear imaging of ACKR3 expression in human breast, lung, and esophageal squamous cell carcinoma cancer xenografts. ACKR3 expression data were extracted from Cancer Cell Line Encyclopedia, The Cancer Genome Atlas, and the Clinical Lung Cancer Genome Project. (89)Zr-ACKR3-mAb was evaluated in vitro and subsequently in vivo by PET and ex vivo biodistribution studies in mice xenografted with breast (MDA-MB-231-ACKR3 [231-ACKR3], MDA-MB-231 [231], MCF7), lung (HCC95), or esophageal (KYSE520) cancer cells. In addition, ACKR3-mAb was radiolabeled with (125)I and evaluated by SPECT imaging and ex vivo biodistribution studies. ACKR3 transcript levels were highest in lung squamous cell carcinoma among the 21 cancer type data extracted from The Cancer Genome Atlas. Also, Clinical Lung Cancer Genome Project data showed that lung squamous cell carcinoma had the highest CXCR7 transcript levels compared with other lung cancer subtypes. The (89)Zr-ACKR3-mAb was produced in 80% ± 5% radiochemical yields with greater than 98% radiochemical purity. In vitro cell uptake of (89)Zr-ACKR3-mAb correlated with gradient levels of cell surface ACKR3 expression observed by flow cytometry. In vivo PET imaging and ex vivo biodistribution studies in mice with breast, lung, and esophageal cancer xenografts consistently showed enhanced (89)Zr-ACKR3-mAb uptake in high-ACKR3-expressing tumors. SPECT imaging of (125)I-ACKR3-mAb showed the versatility of ACKR3-mAb for in vivo monitoring of ACKR3 expression. Data from this study suggest ACKR3 to be a viable diagnostic marker and demonstrate the utility of radiolabeled ACKR3-mAb for in vivo visualization of ACKR3-overexpressing malignancies. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Enhanced oral bioavailability and sustained delivery of glimepiride via niosomal encapsulation: in-vitro characterization and in-vivo evaluation.

PubMed

Mohsen, Amira Mohamed; AbouSamra, Mona Mahmoud; ElShebiney, Shaimaa Ahmed

2017-08-01

This study was designed to investigate the potency of niosomes, for glimepiride (GLM) encapsulation, aiming at enhancing its oral bioavailability and hypoglycemic efficacy. Niosomes containing nonionic surfactants (NIS) were prepared by thin film hydration technique and characterized. In-vitro release study was performed using a dialysis technique. In-vivo pharmacodynamic studies, as well as pharmacokinetic evaluation were performed on alloxan-induced diabetic rats. GLM niosomes exhibited high-entrapment efficiency percentages (E.E. %) up to 98.70% and a particle size diameter ranging from 186.8 ± 18.69 to 797.7 ± 12.45 nm, with negatively charged zeta potential (ZP). Different GLM niosomal formulation showed retarded in vitro release, compared to free drug. In-vivo studies revealed the superiority of GLM niosomes in lowering blood glucose level (BGL) and in maintaining a therapeutic level of GLM for a longer period of time, as compared to free drug and market product. There was no significant difference between mean plasma AUC 0-48 hr of GLM-loaded niosomes and that of market product. GLM-loaded niosomes exhibited seven-fold enhancement in relative bioavailability in comparison with free drug. These findings reinforce the potential use of niosomes for enhancing the oral bioavailability and prolonged delivery of GLM via oral administration.

Validation of cone-beam computed tomography and magnetic resonance imaging of the porcine spine: a comparative study with multidetector computed tomography and anatomical specimens.

PubMed

de Freitas, Ricardo Miguel Costa; Andrade, Celi Santos; Caldas, José Guilherme Mendes Pereira; Kanas, Alexandre Fligelman; Cabral, Richard Halti; Tsunemi, Miriam Harumi; Rodríguez, Hernán Joel Cervantes; Rabbani, Said Rahnamaye

2015-05-01

New spinal interventions or implants have been tested on ex vivo or in vivo porcine spines, as they are readily available and have been accepted as a comparable model to human cadaver spines. Imaging-guided interventional procedures of the spine are mostly based on fluoroscopy or, still, on multidetector computed tomography (MDCT). Cone-beam computed tomography (CBCT) and magnetic resonance imaging (MRI) are also available methods to guide interventional procedures. Although some MDCT data from porcine spines are available in the literature, validation of the measurements on CBCT and MRI is lacking. To describe and compare the anatomical measurements accomplished with MDCT, CBCT, and MRI of lumbar porcine spines to determine if CBCT and MRI are also useful methods for experimental studies. An experimental descriptive-comparative study. Sixteen anatomical measurements of an individual vertebra from six lumbar porcine spines (n=36 vertebrae) were compared with their MDCT, CBCT, and MRI equivalents. Comparisons were made for the absolute values of the parameters. Similarities were found in all imaging methods. Significant correlation (p<.05) was observed with all variables except those that included cartilaginous tissue from the end plates when the anatomical study was compared with the imaging methods. The CBCT and MRI provided imaging measurements of the lumbar porcine spines that were similar to the anatomical and MDCT data, and they can be useful for specific experimental research studies. Copyright © 2015 Elsevier Inc. All rights reserved.

A Time Use Diary Study of Adult Everyday Writing Behavior

ERIC Educational Resources Information Center

Cohen, Dale J.; White, Sheida; Cohen, Steffaney B.

2011-01-01

The present study documents everyday adult writing by type of text and medium (computer or paper) in an "in vivo" diary study. The authors compare writing patterns by gender, race/ethnicity, educational attainment, age and working status. The study results reveal that (a) writing time varied with demographic variables for networkers, but…

NUTRALYS® pea protein: characterization of in vitro gastric digestion and in vivo gastrointestinal peptide responses relevant to satiety

PubMed Central

Overduin, Joost; Guérin-Deremaux, Laetitia; Wils, Daniel; Lambers, Tim T.

2015-01-01

Background Pea protein (from Pisum sativum) is under consideration as a sustainable, satiety-inducing food ingredient. Objective In the current study, pea-protein-induced physiological signals relevant to satiety were characterized in vitro via gastric digestion kinetics and in vivo by monitoring post-meal gastrointestinal hormonal responses in rats. Design Under in vitro simulated gastric conditions, the digestion of NUTRALYS® pea protein was compared to that of two dairy proteins, slow-digestible casein and fast-digestible whey. In vivo, blood glucose and gastrointestinal hormonal (insulin, ghrelin, cholecystokinin [CCK], glucagon-like peptide 1 [GLP-1], and peptide YY [PYY]) responses were monitored in nine male Wistar rats following isocaloric (11 kcal) meals containing 35 energy% of either NUTRALYS® pea protein, whey protein, or carbohydrate (non-protein). Results In vitro, pea protein transiently aggregated into particles, whereas casein formed a more enduring protein network and whey protein remained dissolved. Pea-protein particle size ranged from 50 to 500 µm, well below the 2 mm threshold for gastric retention in humans. In vivo, pea-protein and whey-protein meals induced comparable responses for CCK, GLP-1, and PYY, that is, the anorexigenic hormones. Pea protein induced weaker initial, but equal 3-h integrated ghrelin and insulin responses than whey protein, possibly due to the slower gastric breakdown of pea protein observed in vitro. Two hours after meals, CCK levels were more elevated in the case of protein meals compared to that of non-protein meals. Conclusions These results indicate that 1) pea protein transiently aggregates in the stomach and has an intermediately fast intestinal bioavailability in between that of whey and casein; 2) pea-protein- and dairy-protein-containing meals were comparably efficacious in triggering gastrointestinal satiety signals. PMID:25882536

Novel lecithin-integrated liquid crystalline nanogels for enhanced cutaneous targeting of terconazole: development, in vitro and in vivo studies.

PubMed

Elnaggar, Yosra Sr; Talaat, Sara M; Bahey-El-Din, Mohammed; Abdallah, Ossama Y

Terconazole (Tr) is the first marketed, most active triazole for vaginal candidiasis. Owing to poor skin permeation and challenging physicochemical properties, Tr was not employed for the treatment of cutaneous candidiasis. This is the first study to investigate the relevance of novel lecithin-integrated liquid crystalline nano-organogels (LCGs) to improve physicochemical characteristics of Tr in order to enable its dermal application in skin candidiasis. Ternary phase diagram was constructed using lecithin/capryol 90/water to identify the region of liquid crystalline organogel. The selected organogel possessed promising physicochemical characteristics based on particle size, rheological behavior, pH, loading efficiency, and in vitro antifungal activity. Microstructure of the selected organogel was confirmed by polarized light microscopy and transmission electron microscopy. Ex vivo and in vivo skin permeation studies revealed a significant 4.7- and 2.7-fold increase in the permeability of Tr-loaded LCG when compared to conventional hydrogel. Moreover, acute irritation study indicated safety and compatibility of liquid crystalline organogel to the skin. The in vivo antifungal activity confirmed the superiority of LCG over the conventional hydrogel for the eradication of Candida infection. Overall, lecithin-based liquid crystalline organogel confirmed its potential as an interesting dermal nanocarrier for skin targeting purpose.

Novel lecithin-integrated liquid crystalline nanogels for enhanced cutaneous targeting of terconazole: development, in vitro and in vivo studies

PubMed Central

Elnaggar, Yosra SR; Talaat, Sara M; Bahey-El-Din, Mohammed; Abdallah, Ossama Y

2016-01-01

Terconazole (Tr) is the first marketed, most active triazole for vaginal candidiasis. Owing to poor skin permeation and challenging physicochemical properties, Tr was not employed for the treatment of cutaneous candidiasis. This is the first study to investigate the relevance of novel lecithin-integrated liquid crystalline nano-organogels (LCGs) to improve physicochemical characteristics of Tr in order to enable its dermal application in skin candidiasis. Ternary phase diagram was constructed using lecithin/capryol 90/water to identify the region of liquid crystalline organogel. The selected organogel possessed promising physicochemical characteristics based on particle size, rheological behavior, pH, loading efficiency, and in vitro antifungal activity. Microstructure of the selected organogel was confirmed by polarized light microscopy and transmission electron microscopy. Ex vivo and in vivo skin permeation studies revealed a significant 4.7- and 2.7-fold increase in the permeability of Tr-loaded LCG when compared to conventional hydrogel. Moreover, acute irritation study indicated safety and compatibility of liquid crystalline organogel to the skin. The in vivo antifungal activity confirmed the superiority of LCG over the conventional hydrogel for the eradication of Candida infection. Overall, lecithin-based liquid crystalline organogel confirmed its potential as an interesting dermal nanocarrier for skin targeting purpose. PMID:27822033

IVIVC for fenofibrate immediate release tablets using solubility and permeability as in vitro predictors for pharmacokinetics.

PubMed

Buch, Philipp; Holm, Per; Thomassen, Jesper Qvist; Scherer, Dieter; Branscheid, Robert; Kolb, Ute; Langguth, Peter

2010-10-01

The goal of this study was to investigate the in vitro-in vivo correlation (IVIVC) for fenofibrate immediate release (IR) tablet formulations based on MeltDose-technique. The in vitro determined drug solubility and permeability data were related to the C(max) values observed from two in vivo human studies. Solubility and permeation studies of fenofibrate were conducted in medium simulating the fasted state conditions in the upper jejunum, containing the surfactant compositions of the six formulations at different concentrations. The behavior of all surfactant compositions was characterized by surface tension, dynamic light scattering, and cryo-TEM. The obtained solubility and permeation data were combined and compared with the C(max) values for the fenofibrate formulations, assuming a 50 mL in vivo dissolution volume. A good IVIVC was observed for five fenofibrate formulations (R(2) = 0.94). The in vitro studies revealed that the formulation compositions containing sodium lauryl sulfate (SLS) interfered with the vesicular drug solubilizing system of the biorelevant medium and antagonized its solubilization capacity. The opposing interaction of surfactants with the emulsifying physiological constituents in intestinal juice should be taken into consideration in order to prevent unsatisfactory in vivo performance of orally administered formulations with low soluble active pharmaceutical ingredients.

ANTIVIRAL ACTIVITY OF DIANTHUS SUPERBUSN L. AGAINST HEPATITIS B VIRUS IN VITRO AND IN VIVO

PubMed Central

Li, Wei-Guo; Wang, He-Qun

2016-01-01

Background: Hepatitis is a viral infection of hepatitis B virus (HBV). Limitations of drug used in the management of it opens the interest related to alternative medicine. The given study deals with the antiviral activity of Dianthus superbusn L. (DSL) against HBV in vitro & in vivo. Material and Methods: In vitro study liver cell line HepG2.2.15 was used by transinfected it with HBV. Cytotoxicity stduy was performed by using different concentrations of DSL such as 50, 100, 200, 500 & 1000 μg/ml. Anti HBV activity of DSL was estimated by assesing the concentration of HBsAg and HbeAg in cell culture medium by using ELISA. Whereas in vivo study was performed on ducklings and antiviral activity of DSL (100, 200, 400 mg/kg) was confirmed by estimating the serum concentration of HBV DNA and histopathology study of hepatocytes in HBV infected ducklings. Result: Result of the study suggested that >500 μg/ml concentration of hydroalcoholic extract of DSL was found tobe cytotoxic. It was also observed that DSL significantly (p<0.05) reduces the concentration of antigenes in cell culture media as per the concentration and days of treatment dependent. Moreover in vivo study confirms the anti viral activity of DSL (200 & 400 mg/kg) as it significantly (p<0.05) decreases the serum concenetration of HBV DNA in HBV infected dukling compared to control group. Histopathology study was also reveals the hepatprotective effect of DSL in HBV infected ducklings. Conclusion: The given study concludes the antiviral activity DSL against HBV by in vitro and in vivo models. PMID:28487893

Diffusion-weighted magnetic resonance imaging in cancer: Reported apparent diffusion coefficients, in-vitro and in-vivo reproducibility

PubMed Central

Jafar, Maysam M; Parsai, Arman; Miquel, Marc E

2016-01-01

There is considerable disparity in the published apparent diffusion coefficient (ADC) values across different anatomies. Institutions are increasingly assessing repeatability and reproducibility of the derived ADC to determine its variation, which could potentially be used as an indicator in determining tumour aggressiveness or assessing tumour response. In this manuscript, a review of selected articles published to date in healthy extra-cranial body diffusion-weighted magnetic resonance imaging is presented, detailing reported ADC values and discussing their variation across different studies. In total 115 studies were selected including 28 for liver parenchyma, 15 for kidney (renal parenchyma), 14 for spleen, 13 for pancreatic body, 6 for gallbladder, 13 for prostate, 13 for uterus (endometrium, myometrium, cervix) and 13 for fibroglandular breast tissue. Median ADC values in selected studies were found to be 1.28 × 10-3 mm2/s in liver, 1.94 × 10-3 mm2/s in kidney, 1.60 × 10-3 mm2/s in pancreatic body, 0.85 × 10-3 mm2/s in spleen, 2.73 × 10-3 mm2/s in gallbladder, 1.64 × 10-3 mm2/s and 1.31 × 10-3 mm2/s in prostate peripheral zone and central gland respectively (combined median value of 1.54×10-3 mm2/s), 1.44 × 10-3 mm2/s in endometrium, 1.53 × 10-3 mm2/s in myometrium, 1.71 × 10-3 mm2/s in cervix and 1.92 × 10-3 mm2/s in breast. In addition, six phantom studies and thirteen in vivo studies were summarized to compare repeatability and reproducibility of the measured ADC. All selected phantom studies demonstrated lower intra-scanner and inter-scanner variation compared to in vivo studies. Based on the findings of this manuscript, it is recommended that protocols need to be optimised for the body part studied and that system-induced variability must be established using a standardized phantom in any clinical study. Reproducibility of the measured ADC must also be assessed in a volunteer population, as variations are far more significant in vivo compared with phantom studies. PMID:26834942

In vivo experimental study on bone regeneration in critical bone defects using PIB nanogels/boron-containing mesoporous bioactive glass composite scaffold

PubMed Central

Chen, Xiaohui; Zhao, Yanbing; Geng, Shinan; Miron, Richard J; Zhang, Qiao; Wu, Chengtie; Zhang, Yufeng

2015-01-01

Purpose In the present study, the fabrication of novel p(N-isopropylacrylamide-co-butyl methylacrylate) (PIB) nanogels was combined with boron-containing mesoporous bioactive glass (B-MBG) scaffolds in order to improve the mechanical properties of PIB nanogels alone. Scaffolds were tested for mechanical strength and the ability to promote new bone formation in vivo. Patients and methods To evaluate the potential of each scaffold in bone regeneration, ovariectomized rats were chosen as a study model to determine the ability of PIB nanogels to stimulate bone formation in a complicated anatomical bone defect. PIB nanogels and PIB nanogels/B-MBG composites were respectively implanted into ovariectomized rats with critical-sized femur defects following treatment periods of 2, 4, and 8 weeks post-implantation. Results Results from the present study demonstrate that PIB nanogels/B-MBG composites showed greater improvement in mechanical strength when compared to PIB nanogels alone. In vivo, hematoxylin and eosin staining revealed significantly more newly formed bone in defects containing PIB nanogels/B-MBG composite scaffolds when compared to PIB nanogels alone. Tartrate-resistant acid phosphatase-positive staining demonstrated that both scaffolds were degraded over time and bone remodeling occurred in the surrounding bone defect as early as 4 weeks post-implantation. Conclusion The results from the present study indicate that PIB nanogels are a potential bone tissue engineering biomaterial able to treat defects of irregular shapes and deformities as an injectable, thermoresponsive, biocompatible hydrogel which undergoes rapid thermal gelation once body temperature is reached. Furthermore, its combination with B-MBG scaffolds improves the mechanical properties and ability to promote new bone formation when compared to PIB nanogels alone. PMID:25653525

In vivo experimental study on bone regeneration in critical bone defects using PIB nanogels/boron-containing mesoporous bioactive glass composite scaffold.

PubMed

Chen, Xiaohui; Zhao, Yanbing; Geng, Shinan; Miron, Richard J; Zhang, Qiao; Wu, Chengtie; Zhang, Yufeng

2015-01-01

In the present study, the fabrication of novel p(N-isopropylacrylamide-co-butyl methylacrylate) (PIB) nanogels was combined with boron-containing mesoporous bioactive glass (B-MBG) scaffolds in order to improve the mechanical properties of PIB nanogels alone. Scaffolds were tested for mechanical strength and the ability to promote new bone formation in vivo. To evaluate the potential of each scaffold in bone regeneration, ovariectomized rats were chosen as a study model to determine the ability of PIB nanogels to stimulate bone formation in a complicated anatomical bone defect. PIB nanogels and PIB nanogels/B-MBG composites were respectively implanted into ovariectomized rats with critical-sized femur defects following treatment periods of 2, 4, and 8 weeks post-implantation. Results from the present study demonstrate that PIB nanogels/B-MBG composites showed greater improvement in mechanical strength when compared to PIB nanogels alone. In vivo, hematoxylin and eosin staining revealed significantly more newly formed bone in defects containing PIB nanogels/B-MBG composite scaffolds when compared to PIB nanogels alone. Tartrate-resistant acid phosphatase-positive staining demonstrated that both scaffolds were degraded over time and bone remodeling occurred in the surrounding bone defect as early as 4 weeks post-implantation. The results from the present study indicate that PIB nanogels are a potential bone tissue engineering biomaterial able to treat defects of irregular shapes and deformities as an injectable, thermoresponsive, biocompatible hydrogel which undergoes rapid thermal gelation once body temperature is reached. Furthermore, its combination with B-MBG scaffolds improves the mechanical properties and ability to promote new bone formation when compared to PIB nanogels alone.

Ex-vivo expansion of red blood cells: how real for transfusion in humans?

PubMed

Migliaccio, Anna Rita; Masselli, Elena; Varricchio, Lilian; Whitsett, Carolyn

2012-03-01

Blood transfusion is indispensable for modern medicine. In developed countries, the blood supply is adequate and safe but blood for alloimmunized patients is often unavailable. Concerns are increasing that donations may become inadequate in the future as the population ages prompting a search for alternative transfusion products. Improvements in culture conditions and proof-of-principle studies in animal models have suggested that ex-vivo expanded red cells may represent such a product. Compared to other cell therapies transfusion poses the unique challenge of requiring great cell doses (2.5×10(12) cells vs 10(7) cells). Although production of such cell numbers is theoretically possible, current technologies generate red cells in numbers sufficient only for safety studies. It is conceived that by the time these studies will be completed, technical barriers to mass cell production will have been eliminated making transfusion with ex-vivo generated red cells a reality. Copyright © 2011 Elsevier Ltd. All rights reserved.

Examples of Mesh and NURBS modelling for in vivo lung counting studies.

PubMed

Farah, Jad; Broggio, David; Franck, Didier

2011-03-01

Realistic calibration coefficients for in vivo counting installations are assessed using voxel phantoms and Monte Carlo calculations. However, voxel phantoms construction is time consuming and their flexibility extremely limited. This paper involves Mesh and non-uniform rational B-splines graphical formats, of greater flexibility, to optimise the calibration of in vivo counting installations. Two studies validating the use of such phantoms and involving geometry deformation and modelling were carried out to study the morphologic effect on lung counting efficiency. The created 3D models fitted with the reference ones, with volumetric differences of <5 %. Moreover, it was found that counting efficiency varies with the inverse of lungs' volume and that the latter primes when compared with chest wall thickness. Finally, a series of different thoracic female phantoms of various cup sizes, chest girths and internal organs' volumes were created starting from the International Commission on Radiological Protection (ICRP) adult female reference computational phantom to give correction factors for the lung monitoring of female workers.

Lower Intrinsic ADP-Stimulated Mitochondrial Respiration Underlies In Vivo Mitochondrial Dysfunction in Muscle of Male Type 2 Diabetic Patients

PubMed Central

Phielix, Esther; Schrauwen-Hinderling, Vera B.; Mensink, Marco; Lenaers, Ellen; Meex, Ruth; Hoeks, Joris; Kooi, Marianne Eline; Moonen-Kornips, Esther; Sels, Jean-Pierre; Hesselink, Matthijs K.C.; Schrauwen, Patrick

2008-01-01

OBJECTIVE—A lower in vivo mitochondrial function has been reported in both type 2 diabetic patients and first-degree relatives of type 2 diabetic patients. The nature of this reduction is unknown. Here, we tested the hypothesis that a lower intrinsic mitochondrial respiratory capacity may underlie lower in vivo mitochondrial function observed in diabetic patients. RESEARCH DESIGN AND METHODS—Ten overweight diabetic patients, 12 first-degree relatives, and 16 control subjects, all men, matched for age and BMI, participated in this study. Insulin sensitivity was measured with a hyperinsulinemic-euglycemic clamp. Ex vivo intrinsic mitochondrial respiratory capacity was determined in permeabilized skinned muscle fibers using high-resolution respirometry and normalized for mitochondrial content. In vivo mitochondrial function was determined by measuring phosphocreatine recovery half-time after exercise using 31P-magnetic resonance spectroscopy. RESULTS—Insulin-stimulated glucose disposal was lower in diabetic patients compared with control subjects (11.2 ± 2.8 vs. 28.9 ± 3.7 μmol · kg−1 fat-free mass · min−1, respectively; P = 0.003), with intermediate values for first-degree relatives (22.1 ± 3.4 μmol · kg−1 fat-free mass · min−1). In vivo mitochondrial function was 25% lower in diabetic patients (P = 0.034) and 23% lower in first-degree relatives, but the latter did not reach statistical significance (P = 0.08). Interestingly, ADP-stimulated basal respiration was 35% lower in diabetic patients (P = 0.031), and fluoro-carbonyl cyanide phenylhydrazone–driven maximal mitochondrial respiratory capacity was 31% lower in diabetic patients (P = 0.05) compared with control subjects with intermediate values for first-degree relatives. CONCLUSIONS—A reduced basal ADP-stimulated and maximal mitochondrial respiratory capacity underlies the reduction in in vivo mitochondrial function, independent of mitochondrial content. A reduced capacity at both the level of the electron transport chain and phosphorylation system underlies this impaired mitochondrial capacity. PMID:18678616

A randomized comparison of laparoscopic, magnetically anchored, and flexible endoscopic cameras in performance and workload between laparoscopic and single-incision surgery.

PubMed

Arain, Nabeel A; Cadeddu, Jeffrey A; Best, Sara L; Roshek, Thomas; Chang, Victoria; Hogg, Deborah C; Bergs, Richard; Fernandez, Raul; Webb, Erin M; Scott, Daniel J

2012-04-01

This study aimed to evaluate the surgeon performance and workload of a next-generation magnetically anchored camera compared with laparoscopic and flexible endoscopic imaging systems for laparoscopic and single-site laparoscopy (SSL) settings. The cameras included a 5-mm 30° laparoscope (LAP), a magnetically anchored (MAGS) camera, and a flexible endoscope (ENDO). The three camera systems were evaluated using standardized optical characteristic tests. Each system was used in random order for visualization during performance of a standardized suturing task by four surgeons. Each participant performed three to five consecutive repetitions as a surgeon and also served as a camera driver for other surgeons. Ex vivo testing was conducted in a laparoscopic multiport and SSL layout using a box trainer. In vivo testing was performed only in the multiport configuration and used a previously validated live porcine Nissen model. Optical testing showed superior resolution for MAGS at 5 and 10 cm compared with LAP or ENDO. The field of view ranged from 39 to 99°. The depth of focus was almost three times greater for MAGS (6-270 mm) than for LAP (2-88 mm) or ENDO (1-93 mm). Both ex vivo and in vivo multiport combined surgeon performance was significantly better for LAP than for ENDO, but no significant differences were detected for MAGS. For multiport testing, workload ratings were significantly less ex vivo for LAP and MAGS than for ENDO and less in vivo for LAP than for MAGS or ENDO. For ex vivo SSL, no significant performance differences were detected, but camera drivers rated the workload significantly less for MAGS than for LAP or ENDO. The data suggest that the improved imaging element of the next-generation MAGS camera has optical and performance characteristics that meet or exceed those of the LAP or ENDO systems and that the MAGS camera may be especially useful for SSL. Further refinements of the MAGS camera are encouraged.

Combined in vivo and ex vivo analysis of mesh mechanics in a porcine hernia model.

PubMed

Kahan, Lindsey G; Lake, Spencer P; McAllister, Jared M; Tan, Wen Hui; Yu, Jennifer; Thompson, Dominic; Brunt, L Michael; Blatnik, Jeffrey A

2018-02-01

Hernia meshes exhibit variability in mechanical properties, and their mechanical match to tissue has not been comprehensively studied. We used an innovative imaging model of in vivo strain tracking and ex vivo mechanical analysis to assess effects of mesh properties on repaired abdominal walls in a porcine model. We hypothesized that meshes with dissimilar mechanical properties compared to native tissue would alter abdominal wall mechanics more than better-matched meshes. Seven mini-pigs underwent ventral hernia creation and subsequent open repair with one of two heavyweight polypropylene meshes. Following mesh implantation with attached radio-opaque beads, fluoroscopic images were taken at insufflation pressures from 5 to 30 mmHg on postoperative days 0, 7, and 28. At 28 days, animals were euthanized and ex vivo mechanical testing performed on full-thickness samples across repaired abdominal walls. Testing was conducted on 13 mini-pig controls, and on meshes separately. Stiffness and anisotropy (the ratio of stiffness in the transverse versus craniocaudal directions) were assessed. 3D reconstructions of repaired abdominal walls showed stretch patterns. As pressure increased, both meshes expanded, with no differences between groups. Over time, meshes contracted 17.65% (Mesh A) and 0.12% (Mesh B; p = 0.06). Mesh mechanics showed that Mesh A deviated from anisotropic native tissue more than Mesh B. Compared to native tissue, Mesh A was stiffer both transversely and craniocaudally. Explanted repaired abdominal walls of both treatment groups were stiffer than native tissue. Repaired tissue became less anisotropic over time, as mesh properties prevailed over native abdominal wall properties. This technique assessed 3D stretch at the mesh level in vivo in a porcine model. While the abdominal wall expanded, mesh-ingrown areas contracted, potentially indicating stresses at mesh edges. Ex vivo mechanics demonstrate that repaired tissue adopts mesh properties, suggesting that a better-matched mesh could reduce changes to abdominal wall mechanics.

Ex vivo rabbit and human corneas as models for bacterial and fungal keratitis.

PubMed

Pinnock, Abigail; Shivshetty, Nagaveni; Roy, Sanhita; Rimmer, Stephen; Douglas, Ian; MacNeil, Sheila; Garg, Prashant

2017-02-01

In the study of microbial keratitis, in vivo animal models often require a large number of animals, and in vitro monolayer cell culture does not maintain the three-dimensional structure of the tissues or cell-to-cell communication of in vivo models. Here, we propose reproducible ex vivo models of single- and dual-infection keratitis as an alternative to in vivo and in vitro models. Excised rabbit and human corneoscleral rims maintained in organ culture were infected using 10 8 cells of Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans or Fusarium solani. The infection was introduced by wounding with a scalpel and exposing corneas to the microbial suspension or by intrastromal injection. Post-inoculation, corneas were maintained for 24 and 48 h at 37 °C. After incubation, corneas were either homogenised to determine colony-forming units (CFU)/cornea or processed for histological examination using routine staining methods. Single- and mixed-species infections were compared. We observed a significant increase in CFU after 48 h compared to 24 h with S. aureus and P. aeruginosa. However, no such increase was observed in corneas infected with C. albicans or F. solani. The injection method yielded an approximately two- to 100-fold increase (p < 0.05) in the majority of organisms from infected corneas. Histology of the scalpel-wounded and injection models indicated extensive infiltration of P. aeruginosa throughout the entire cornea, with less infiltration observed for S. aureus, C. albicans and F. solani. The models also supported dual infections. Both scalpel wounding and injection methods are suitable for inducing infection of ex vivo rabbit and human cornea models. These simple and reproducible models will be useful as an alternative to in vitro and in vivo models for investigating the detection and treatment of microbial keratitis, particularly when this might be due to two infective organisms.

Pulsed and oscillating gradient MRI for assessment of cell size and Extracellular space (POMACE) in mouse gliomas

PubMed Central

Reynaud, Olivier; Winters, Kerryanne Veronica; Hoang, Dung Minh; Wadghiri, Youssef Zaim; Novikov, Dmitry S.; Kim, Sungheon Gene

2016-01-01

Solid tumor microstructure is related to aggressiveness of tumor, interstitial pressure and drug delivery pathways that are closely associated with treatment response, metastatic spread and prognosis. In this study, we introduce a novel diffusion MRI data analysis framework, Pulsed and Oscillating gradient MRI for Assessment of Cell size and Extracellular space (POMACE), and demonstrate its feasibility in a mouse tumor model. In vivo and ex vivo POMACE experiments were performed on mice bearing the GL261 murine glioma model (n=8). Since the complete diffusion time-dependence is in general non-analytical, the tumor microstructure was modeled in an appropriate time/frequency regime by impermeable spheres (radius Rcell, intracellular diffusivity Dics) surrounded by extracellular space (approximated by constant apparent diffusivity Decs in volume fraction ECS). POMACE parametric maps (ECS, Rcell, Dics, Decs) were compared with conventional diffusion weighted imaging metrics, electron microscopy (EM), alternative ECS determination based on effective medium theory (EMT), and optical microscopy performed on the same samples. It was shown that Decs can be approximated by its long-time tortuosity limit in the range [1/(88 Hz) - 31 ms]. ECS estimations (44±7% in vivo and 54±11% ex vivo) were in agreement with EMT-based ECS and literature on brain gliomas. Ex vivo, ECS maps correlated well with optical microscopy. Cell sizes (Rcell=4.8±1.3 in vivo and 4.3±1.4 μm ex vivo) were consistent with EM measurements (4.7±1.8 μm). In conclusion, Rcell and ECS can be quantified and mapped in vivo and ex vivo in brain tumors using the proposed POMACE method. Our experimental results support that POMACE provides a way to interpret the frequency- or time-dependence of the diffusion coefficient in tumors in terms of objective biophysical parameters of neuronal tissue, which can be used for non-invasive monitoring of preclinical cancer studies and treatment efficacy. PMID:27448059

Comparison of in vivo vs. ex situ obtained material properties of sheep common carotid artery.

PubMed

Smoljkić, Marija; Verbrugghe, Peter; Larsson, Matilda; Widman, Erik; Fehervary, Heleen; D'hooge, Jan; Vander Sloten, Jos; Famaey, Nele

2018-05-01

Patient-specific biomechanical modelling can improve preoperative surgical planning. This requires patient-specific geometry as well as patient-specific material properties as input. The latter are, however, still quite challenging to estimate in vivo. This study focuses on the estimation of the mechanical properties of the arterial wall. Firstly, in vivo pressure, diameter and thickness of the arterial wall were acquired for sheep common carotid arteries. Next, the animals were sacrificed and the tissue was stored for mechanical testing. Planar biaxial tests were performed to obtain experimental stress-stretch curves. Finally, parameters for the hyperelastic Mooney-Rivlin and Gasser-Ogden-Holzapfel (GOH) material model were estimated based on the in vivo obtained pressure-diameter data as well as on the ex situ experimental stress-stretch curves. Both material models were able to capture the in vivo behaviour of the tissue. However, in the ex situ case only the GOH model provided satisfactory results. When comparing different fitting approaches, in vivo vs. ex situ, each of them showed its own advantages and disadvantages. The in vivo approach estimates the properties of the tissue in its physiological state while the ex situ approach allows to apply different loadings to properly capture the anisotropy of the tissue. Both of them could be further enhanced by improving the estimation of the stress-free state, i.e. by adding residual circumferential stresses in vivo and by accounting for the flattening effect of the tested samples ex vivo. • Competing interests: none declared • Word count: 4716. Copyright © 2018. Published by Elsevier Ltd.

A method to rapidly and accurately compare relative efficacies of non-invasive imaging reporter genes in a mouse model, and its application to luciferase reporters

PubMed Central

Gil, Jose S.; Machado, Hidevaldo B.; Herschman, Harvey R.

2013-01-01

Purpose Our goal is to develop a simple, quantitative, robust method to compare the efficacy of imaging reporter genes in culture and in vivo. We describe an adenoviral vector-liver transduction procedure, and compare the luciferase reporter efficacies. Procedures Alternative reporter genes are expressed in a common adenoviral vector. Vector amounts used in vivo are based on cell culture titrations, ensuring the same transduction efficacy is used for each vector. After imaging, in vivo and in vitro values are normalized to hepatic vector transduction using quantitative real-time PCR. Results We assayed standard firefly luciferase (FLuc), enhanced firefly luciferase (EFLuc), luciferase 2 (Luc2), humanized Renilla luciferase (hRLuc), Renilla luciferase 8.6-535 (RLuc8.6), and a membrane-bound Gaussia luciferase variant (extGLuc) in cell culture and in vivo. We observed a greater that 100-fold increase in bioluminescent signal for both EFLuc and Luc2 when compared to FLuc, and a greater than 106-fold increase for RLuc8.6 when compared to hRLuc. ExtGLuc was not detectable in liver. Conclusions Our findings contrast, in some cases, with conclusions drawn in prior comparisons of these reporter genes, and demonstrate the need for a standardized method to evaluate alternative reporter genes in vivo. Our procedure can be adapted for reporter genes that utilize alternative imaging modalities (fluorescence, bioluminescence, MRI, SPECT, PET). PMID:21850545

Optically Sectioned Imaging of Microvasculature of In-Vivo and Ex-Vivo Thick Tissue Models with Speckle-illumination HiLo Microscopy and HiLo Image Processing Implementation in MATLAB Architecture

NASA Astrophysics Data System (ADS)

Suen, Ricky Wai

The work described in this thesis covers the conversion of HiLo image processing into MATLAB architecture and the use of speckle-illumination HiLo microscopy for use of ex-vivo and in-vivo imaging of thick tissue models. HiLo microscopy is a wide-field fluorescence imaging technique and has been demonstrated to produce optically sectioned images comparable to confocal in thin samples. The imaging technique was developed by Jerome Mertz and the Boston University Biomicroscopy Lab and has been implemented in our lab as a stand-alone optical setup and a modification to a conventional fluorescence microscope. Speckle-illumination HiLo microscopy combines two images taken under speckle-illumination and standard uniform-illumination to generate an optically sectioned image that reject out-of-focus fluorescence. The evaluated speckle contrast in the images is used as a weighting function where elements that move out-of-focus have a speckle contrast that decays to zero. The experiments shown here demonstrate the capability of our HiLo microscopes to produce optically-sectioned images of the microvasculature of ex-vivo and in-vivo thick tissue models. The HiLo microscope were used to image the microvasculature of ex-vivo mouse heart sections prepared for optical histology and the microvasculature of in-vivo rodent dorsal window chamber models. Studies in label-free surface profiling with HiLo microscopy is also presented.

Laser probes for noninvasive coagulation of subsurface tissues

NASA Astrophysics Data System (ADS)

Chung, Chia-Chun; Permpongkosol, Sompol; Varkarakis, Ioannis M.; Lima, Guilherme; Franco, Nicholas; Hayman, Michael H.; Nicol, Theresa; Fried, Nathaniel M.

2006-02-01

Previous ex vivo tissue studies utilizing deep laser heating combined with contact cooling of the tissue surface produced noninvasive thermal destruction of subsurface tissue structures in skin and liver samples. This study describes the design and preliminary in vivo testing of two integrated laser/cooling probes for simultaneous Nd:YAG laser irradiation and sapphire contact cooling of liver and skin tissues in an in vivo, acute porcine model for potential use in laparoscopic and endoscopic surgery. Nd:YAG laser radiation with a wavelength of 1.06 μm, power of 20 W, 7.5-mm-diameter spot, 500-ms pulse length, and repetition rate of 0.625 Hz, was delivered to the tissue with a total irradiation time of 16 s. The tissue surface was continuously cooled with a sapphire plate maintained at -5 °C, and with pre- and post-ablation cooling times measuring 120 s and 30 s, resulting in a total operation time of 166 s per a lesion. Thermal lesions were created in liver and skin at a 1-mm depth below the tissue surface and with a 3-4 mm diameter. The laser parameters and lesion dimensions were comparable to previous ex vivo tissue studies. Preliminary in vivo animal studies demonstrate noninvasive creation of subsurface thermal lesions in tissue using Nd:YAG laser irradiation in conjunction with sapphire contact cooling. Chronic wound healing studies will be necessary to optimize the laser and cooling parameters. Potential clinical applications include endoscopic laser treatment of female stress urinary incontinence and thermal coagulation of early stage bladder tumors.

In Vivo versus Augmented Reality Exposure in the Treatment of Small Animal Phobia: A Randomized Controlled Trial.

PubMed

Botella, Cristina; Pérez-Ara, M Ángeles; Bretón-López, Juana; Quero, Soledad; García-Palacios, Azucena; Baños, Rosa María

2016-01-01

Although in vivo exposure is the treatment of choice for specific phobias, some acceptability problems have been associated with it. Virtual Reality exposure has been shown to be as effective as in vivo exposure, and it is widely accepted for the treatment of specific phobias, but only preliminary data are available in the literature about the efficacy of Augmented Reality. The purpose of the present study was to examine the efficacy and acceptance of two treatment conditions for specific phobias in which the exposure component was applied in different ways: In vivo exposure (N = 31) versus an Augmented Reality system (N = 32) in a randomized controlled trial. "One-session treatment" guidelines were followed. Participants in the Augmented Reality condition significantly improved on all the outcome measures at post-treatment and follow-ups. When the two treatment conditions were compared, some differences were found at post-treatment, favoring the participants who received in vivo exposure. However, these differences disappeared at the 3- and 6-month follow-ups. Regarding participants' expectations and satisfaction with the treatment, very positive ratings were reported in both conditions. In addition, participants from in vivo exposure condition considered the treatment more useful for their problem whereas participants from Augmented Reality exposure considered the treatment less aversive. Results obtained in this study indicate that Augmented Reality exposure is an effective treatment for specific phobias and well accepted by the participants.

In Vivo versus Augmented Reality Exposure in the Treatment of Small Animal Phobia: A Randomized Controlled Trial

PubMed Central

Botella, Cristina; Pérez-Ara, M. Ángeles; Bretón-López, Juana; Quero, Soledad; García-Palacios, Azucena; Baños, Rosa María

2016-01-01

Although in vivo exposure is the treatment of choice for specific phobias, some acceptability problems have been associated with it. Virtual Reality exposure has been shown to be as effective as in vivo exposure, and it is widely accepted for the treatment of specific phobias, but only preliminary data are available in the literature about the efficacy of Augmented Reality. The purpose of the present study was to examine the efficacy and acceptance of two treatment conditions for specific phobias in which the exposure component was applied in different ways: In vivo exposure (N = 31) versus an Augmented Reality system (N = 32) in a randomized controlled trial. “One-session treatment” guidelines were followed. Participants in the Augmented Reality condition significantly improved on all the outcome measures at post-treatment and follow-ups. When the two treatment conditions were compared, some differences were found at post-treatment, favoring the participants who received in vivo exposure. However, these differences disappeared at the 3- and 6-month follow-ups. Regarding participants’ expectations and satisfaction with the treatment, very positive ratings were reported in both conditions. In addition, participants from in vivo exposure condition considered the treatment more useful for their problem whereas participants from Augmented Reality exposure considered the treatment less aversive. Results obtained in this study indicate that Augmented Reality exposure is an effective treatment for specific phobias and well accepted by the participants. PMID:26886423

In vivo near-infrared fluorescence imaging of Leishmania amazonensis expressing infrared fluorescence protein (iRFP) for real-time monitoring of cutaneous leishmaniasis in mice.

PubMed

Oliveira, Janaina Correia; da Silva, Aline Caroline; Oliveira, Renato Antonio Dos Santos; Pereira, Valéria Rêgo Alves; Gil, Laura Helena Vega Gonzales

2016-11-01

The use of Leishmania amazonensis-infected BALB/c mice is an important model for the study of experimental cutaneous leishmaniasis. Here we report the development of a non-invasive method to directly evaluate and measure parasite burden during the course of the infection, based on the near-infrared fluorescence detection of a recombinant L. amazonensis strain. So, we generated a L. amazonensis strain that stably expresses the near-infrared protein (iRFP) gene and compared the maintenance of its vitro and in vivo characteristics, such as fitness, pathogenicity and fluorescence emission. After that, we followed the disease development, as well as the parasite burden in BALB/c mice footpads infected with L. amazonensis-iRFP, by using an in vivo near-infrared fluorescence scanner. In vitro results showed a linear correlation between the fluorescence emission and the number of parasites. The in vivo study showed that the use of iRFP-transfected L. amazonensis enables the monitoring of parasite burden by measuring fluorescence signals. Therefore, this technique can be confidently used to directly monitor parasitic load and infection overtime and could be an excellent tool for in vitro and in vivo screening of anti-leishmanial drugs and vaccine efficiency. This is the first report of the use of the near-infrared fluorescence imaging technique for monitoring in vivo cutaneous leishmaniasis. Copyright © 2016 Elsevier B.V. All rights reserved.

Quantification of fibronectin as a method to assess ex vivo extracellular matrix remodeling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bager, C.L., E-mail: cba@nordicbioscience.com; Technical University of Denmark; Gudmann, N.

Altered architecture, composition and quality of the extracellular matrix (ECM) are pathological hallmarks of several inflammatory and fibro-proliferative pathological processes such as osteoarthritis (OA), rheumatoid arthritis (RA), fibrosis and cancer. One of the most important components of the ECM is fibronectin. Fibronectin serves as an adhesion molecule anchoring cells to the underlying basement membrane through direct interaction with integrin receptors. Fibronectin hereby modulates the properties of the ECM and affects cellular processes. Quantification of fibronectin remodeling could therefore be used to assess the changes in the ECM that occur during progression of fibro-proliferative pathologies. Ex vivo models are becoming state-of-the-art toolsmore » to study ECM remodeling as the cellular composition and the organization of the ECM are preserved. Ex vivo models may therefore be a valuable tool to study the ECM remodeling that occurs during progression of fibro-proliferative pathologies. The aim of this study was to quantify fibronectin remodeling in ex vivo models of cartilage and cancer. A competitive The enzyme-linked immunosorbent assay (ELISA) against the C-terminus of fibronectin was developed (FBN-C). The assay was evaluated in relation to specificity, technical performance and as a marker for quantification of fibronectin in cartilage and cancer ex vivo models. The ELISA was specific and technically stable. Cleavage of tumor tissue with MMP-2 released significantly higher levels of FBN-C compared to tissue with buffer only and western blot analysis revealed that FBN-C recognizes both full length and degraded fibronectin. When ex vivo cartilage cultures were stimulated with the anabolic factor TGFβ and catabolic factors TNF-α and OSM, significantly higher levels of FBN-C were found in the conditioned media. Lastly, FBN-C was released from a cancer ex vivo model. In conclusion, we were able to quantify fibronectin remodeling in ex vivo models of cartilage and cancer. Quantification of fibronectin remodeling could be a valuable tool to understand ECM remodeling in ex vivo models of fibro-proliferative pathologies.« less

Mechanism of the stationary canalicular excretion of tributylmethyl ammonium in rats with a CCl4-induced acute hepatic injury.

PubMed

Choi, Min-Koo; Song, Im-Sook; Park, So-Ra; Hong, Soon-Sun; Kim, Dae-Duk; Chung, Suk-Jae; Shim, Chang-Koo

2005-02-01

The in vivo canalicular excretion clearance of tributylmethyl ammonium (TBuMA), a P-glycoprotein (P-gp) substrate, was previously reported to be unaffected by the induction of an experimental hepatic injury (EHI) by CCl(4) despite the increased expression of P-gp in the EHI liver. The objective of this study, therefore, was to elucidate the mechanism for the unchanged canalicular excretion clearance of TBuMA in EHI rats. TBuMA uptake was increased in cLPM vesicles from EHI rats compared with that from control rats. The total bile salt concentration in EHI liver was significantly reduced compared with that in a control liver. Because, in our previous studies, the uptake of TBuMA by cLPM vesicles was found to be significantly enhanced in the presence of bile salts, the reduction in bile salt levels in the EHI liver may be related to the unaltered TBuMA clearance. Despite the fact that the uptake of TBuMA by cLPM vesicles was increased by the addition of an EHI liver extract, the extent of the increase was comparatively less compared to the addition of a control liver extract. The in vivo excretion clearance of TBuMA was increased in a taurodeoxycholate dose-dependent manner in EHI rats. These observations suggest, therefore, that despite the induction of P-gp expression by the EHI, the in vivo canalicular excretion clearance of TBuMA remains unaltered as the result of an offset by reduced levels of bile salt(s). Copyright 2004 Wiley-Liss, Inc.

A Phase 1 Trial to Assess the Safety, Acceptability, Pharmacokinetics, and Pharmacodynamics of a Novel Dapivirine Vaginal Film.

PubMed

Bunge, Katherine E; Dezzutti, Charlene S; Rohan, Lisa C; Hendrix, Craig W; Marzinke, Mark A; Richardson-Harman, Nicola; Moncla, Bernard J; Devlin, Brid; Meyn, Leslie A; Spiegel, Hans M L; Hillier, Sharon L

2016-04-15

Films may deliver antiretroviral drugs efficiently to mucosal tissues. In this first in-human trial of a vaginal film for delivering the nonnucleoside reverse transcriptase inhibitor dapivirine, safety, pharmacokinetics, and pharmacodynamics of film and gel formulations were compared with placebo. Sixty-one healthy HIV-negative women were randomized to daily dapivirine (0.05%) or placebo gel, or dapivirine (1.25 mg) or placebo film for seven days. The proportion of participants experiencing grade 2 and higher adverse events related to study product were compared. Plasma dapivirine concentrations were quantified. Paired cervical and vaginal tissue biopsies obtained ∼2 hours after the last dose were measured for tissue drug concentration and exposed to HIV in an ex vivo challenge assay. Two grade 2 related adverse events occurred in the placebo film group. Women randomized to gel and film products had 4 log10 higher of dapivirine in cervical and vaginal tissues than plasma. Although gel and film users had comparable plasma dapivirine concentrations, tissue concentrations of dapivirine were 3-5 times higher in the gel users when compared with film users. HIV replication in the ex vivo challenge assay was significantly reduced in vaginal tissues from women randomized to dapivirine film or gel; furthermore, tissue drug concentrations were highly correlated with HIV protection. Women rated the film more comfortable with less leakage but found it more difficult to insert than gel. Both film and gel delivered dapivirine at concentrations sufficient to block HIV ex vivo. This proof-of-concept study suggests film formulations for microbicides merit further investigation.

Experience with the first 50 ex vivo lung perfusions in clinical transplantation.

PubMed

Cypel, Marcelo; Yeung, Jonathan C; Machuca, Tiago; Chen, Manyin; Singer, Lianne G; Yasufuku, Kazuhiro; de Perrot, Marc; Pierre, Andrew; Waddell, Thomas K; Keshavjee, Shaf

2012-11-01

Normothermic ex vivo lung perfusion is a novel method to evaluate and improve the function of injured donor lungs. We reviewed our experience with 50 consecutive transplants after ex vivo lung perfusion. A retrospective study using prospectively collected data was performed. High-risk brain death donor lungs (defined as Pao(2)/Fio(2) <300 mm Hg or lungs with radiographic or clinical findings of pulmonary edema) and lungs from cardiac death donors were subjected to 4 to 6 hours of ex vivo lung perfusion. Lungs that achieved stable airway and vascular pressures and Pao(2)/Fio(2) greater than 400 mm Hg during ex vivo lung perfusion were transplanted. The primary end point was the incidence of primary graft dysfunction grade 3 at 72 hours after transplantation. End points were compared with lung transplants not treated with ex vivo lung perfusion (controls). A total of 317 lung transplants were performed during the study period (39 months). Fifty-eight ex vivo lung perfusion procedures were performed, resulting in 50 transplants (86% use). Of these, 22 were from cardiac death donors and 28 were from brain death donors. The mean donor Pao(2)/Fio(2) was 334 mm Hg in the ex vivo lung perfusion group and 452 mm Hg in the control group (P = .0001). The incidence of primary graft dysfunction grade 3 at 72 hours was 2% in the ex vivo lung perfusion group and 8.5% in the control group (P = .14). One patient (2%) in the ex vivo lung perfusion group and 7 patients (2.7%) in the control group required extracorporeal lung support for primary graft dysfunction (P = 1.00). The median time to extubation, intensive care unit stay, and hospital length of stay were 2, 4, and 20 days, respectively, in the ex vivo lung perfusion group and 2, 4, and 23 days, respectively, in the control group (P > .05). Thirty-day mortality (4% in the ex vivo lung perfusion group and 3.5% in the control group, P = 1.00) and 1-year survival (87% in the ex vivo lung perfusion group and 86% in the control group, P = 1.00) were similar in both groups. Transplantation of high-risk donor lungs after 4 to 6 hours of ex vivo lung perfusion is safe, and outcomes are similar to those of conventional transplants. Ex vivo lung perfusion improved our center use of donor lungs, accounting for 20% of our current lung transplant activity. Copyright © 2012 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

Thiolated xyloglucan: Synthesis, characterization and evaluation as mucoadhesive in situ gelling agent.

PubMed

Mahajan, Hitendra S; Tyagi, Vinod Kumar; Patil, Ravindra R; Dusunge, Sanket B

2013-01-16

The objective of present study was to enhance bioadhesive potential of xyloglucan by thiolation. Thiolation of xyloglucan was achieved with esterification with thioglycolic acid. Thiolated xyloglucan was characterized by NMR, DSC, and XRD analysis. Thiolated xyloglucan was determined to possess 4mmol of thiol groups/g of polymer by Ellman's method. Comparative evaluation of mucoadhesive property of ondansetron containing in situ gel system of xyloglucan and thiolated xyloglucan using sheep nasal mucosa revealed higher ex vivo bioadhesion time of thiolated xyloglucan as compared to xyloglucan. Improved mucoadhesive property of thiolated xyloglucan over the xyloglucan can be attributed to the formation of disulfide bond between mucus and thiolated xyloglucan. Ex vivo permeation study conducted using sheep nasal showed improved drug permeation in formulation based on thiolated xyloglucan. In conclusion, thiolation of xyloglucan improves its bioadhesion and drug permeation without affecting the resultant gel properties. Copyright © 2012 Elsevier Ltd. All rights reserved.

Early and late mammalian responses to heavy charged particles

NASA Technical Reports Server (NTRS)

Ainsworth, E. J.

1986-01-01

This overview summarizes murine results on acute lethality responses, inactivation of marrow CFU-S and intestinal microcolonies, testes weight loss, life span shortening, and posterior lens opacification in mice irradiated with heavy charged particles. RBE-LET relationships for these mammalian responses are compared with results from in vitro studies. The trend is that the maximum RBE for in vivo responses tends to be lower and occurs at a lower LET than for inactivation of V79 and T-1 cells in culture. Based on inactivation cross sections, the response of CFU-S in vivo conforms to expectations from earlier studies with prokaryotic systems and mammalian cells in culture. Effects of heavy ions are compared with fission spectrum neutrons, and the results are consistent with the interpretation that RBEs are lower than for fission neutrons at about the same LET, probably due to differences in track structure.

Mechanical properties of a new mica-based machinable glass ceramic for CAD/CAM restorations.

PubMed

Thompson, J Y; Bayne, S C; Heymann, H O

1996-12-01

Machinable ceramics (Vita Mark II and Dicor MGC) exhibit good short-term clinical performance, but long-term in vivo fracture resistance is still being monitored. The relatively low fracture toughness of currently available machinable ceramics restricts their use to conservative inlays and onlays. A new machinable glass ceramic (MGC-F) has been developed (Corning Inc.) with enhanced fluorescence and machinability. The purpose of this study was to characterize and compare key mechanical properties of MGC-F to Dicor MGC-Light, Dicor MGC-Dark, and Vita Mark II glass ceramics. The mean fracture toughness and indented biaxial flexure strength of MGC-F were each significantly greater (p < or = 0.01) than that of Dicor MGC-Light, Dicor MGC-Dark, and Vita Mark II ceramic materials. The results of this study indicate the potential for better in vivo fracture resistance of MGC-F compared with existing machinable ceramic materials for CAD/CAM restorations.

Laser-activated solid protein bands for peripheral nerve repair: an vivo study.

PubMed

Lauto, A; Trickett, R; Malik, R; Dawes, J M; Owen, E R

1997-01-01

Severed tibial nerves in rats were repaired using a novel technique, utilizing a semiconductor diode-laser-activated protein solder applied longitudinally across the join. Welding was produced by selective laser denaturation of solid solder bands containing the dye indocyanine green. An in vivo study, using 48 adult male Wistar rats, compared conventional microsuture-repaired tibial nerves with laser solder-repaired nerves. Nerve repairs were characterised immediately after surgery and after 3 months. Successful regeneration with average compound muscle action potentials of 2.5 +/- 0.5 mV and 2.7 +/- 0.3 mV (mean and standard deviation) was demonstrated for the laser-soldered nerves and the sutured nerves, respectively. Histopathology confirmed comparable regeneration of axons in laser- and suture-operated nerves. The laser-based nerve repair technique was easier and faster than microsuture repair, minimising manipulation damage to the nerve.

Dosimetric study and in-vivo dose verification for conformal avoidance treatment of anal adenocarcinoma using helical tomotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Han Chunhui; Chen Yijen; Liu An

2007-04-01

This study evaluated the efficacy of using helical tomotherapy for conformal avoidance treatment of anal adenocarcinoma. We retrospectively generated step-and-shoot intensity-modulated radiotherapy (sIMRT) plans and helical tomotherapy plans for two anal cancer patients, one male and one female, who were treated by the sIMRT technique. Dose parameters for the planning target volume (PTV) and the organs-at-risk (OARs) were compared between the sIMRT and the helical tomotherapy plans. The helical tomotherapy plans showed better dose homogeneity in the PTV, better dose conformity around the PTV, and, therefore, better sparing of nearby OARs compared with the sIMRT plans. In-vivo skin dose measurementsmore » were performed during conformal avoidance helical tomotherapy treatment of an anal cancer patient to verify adequate delivery of skin dose and sparing of OARs.« less

Non-invasive grading of astrocytic tumours from the relative contents of myo-inositol and glycine measured by in vivo MRS.

PubMed

Candiota, A P; Majós, C; Julià-Sapé, M; Cabañas, M; Acebes, J J; Moreno-Torres, A; Griffiths, J R; Arús, C

2011-01-01

MRI and MRS are established methodologies for evaluating intracranial lesions. One MR spectral feature suggested for in vivo grading of astrocytic tumours is the apparent myo-lnositol (ml) intensity (ca 3.55 ppm) at short echo times, although glycine (gly) may also contribute in vivo to this resonance. The purpose of this study was to quantitatively evaluate the ml + gly contribution to the recorded spectral pattern in vivo and correlate it with in vitro data obtained from perchloric acid extraction of tumour biopsies. Patient spectra (n = 95) at 1.5T at short (20-31 ms) and long (135-136 ms) echo times were obtained from the INTERPRET MRS database (http://gabrmn.uab.eslinterpretvalidateddbl). Phantom spectra were acquired with a comparable protocol. Spectra were automatically processed and the ratios of the (ml + gly) to Cr peak heights ((ml + gly)/Cr) calculated. Perchloric acid extracts of brain tumour biopsies were analysed by high-resolution NMR at 9.4T. The ratio (ml + gly)/Cr decreased significantly with astrocytic grade in vivo between low-grade astrocytoma (A2) and glioblastoma multiforme (GBM). In vitro results displayed a somewhat different tendency, with anaplastic astrocytomas having significantly higher (ml + gly)/Cr than A2 and GBM. The discrepancy between in vivo and in vitro data suggests that the NMR visibility of glycine in glial brain tumours is restricted in vivo.

In vivo near infrared (NIRS) sensor attachment using fibrin bioadhesive

NASA Astrophysics Data System (ADS)

Macnab, Andrew; Pagano, Roberto; Kwon, Brian; Dumont, Guy; Shadgan, Babak

2018-02-01

Background: `Tisseel' (Baxter Healthcare, Deerfield, IL) is a fibrin-based sealant that is commonly used during spine surgery to augment dural repairs. We wish to intra-operatively secure a near infrared spectroscopy (NIRS) sensor to the dura in order to monitor the tissue hemodynamics of the underlying spinal cord. To determine if `Tisseel' sealant adversely attenuates NIR photon transmission. Methods: We investigated `Tisseel' in both an in vitro and in vivo paradigm. For in vitro testing, we used a 1 mm pathlength cuvette containing either air or `Tisseel' interposed between a NIR light source (760 and 850 nm) and a photodiode detector and compared transmittance. For in vivo testing, a continuous wave (760 and 850 nm) spatiallyresolved NIRS device was placed over the triceps muscle using either conventional skin apposition (overlying adhesive bandage) or bioadhesion with `Tisseel'. Raw optical data and tissue saturation index (TSI%) collected at rest were compared. Results: In-vitro NIR light absorption by `Tisseel' was very high, with transmittance reduced by 95% compared to air. In-vivo muscle TSI% values were 80% with conventional attachment and 20% using fibrin glue. Conclusion: The optical properties of `Tisseel' significantly attenuate NIR light during in-vitro transmittance and critically compromise photon transmission in-vivo.

Neurons derived from different brain regions are inherently different in vitro: a novel multiregional brain-on-a-chip.

PubMed

Dauth, Stephanie; Maoz, Ben M; Sheehy, Sean P; Hemphill, Matthew A; Murty, Tara; Macedonia, Mary Kate; Greer, Angie M; Budnik, Bogdan; Parker, Kevin Kit

2017-03-01

Brain in vitro models are critically important to developing our understanding of basic nervous system cellular physiology, potential neurotoxic effects of chemicals, and specific cellular mechanisms of many disease states. In this study, we sought to address key shortcomings of current brain in vitro models: the scarcity of comparative data for cells originating from distinct brain regions and the lack of multiregional brain in vitro models. We demonstrated that rat neurons from different brain regions exhibit unique profiles regarding their cell composition, protein expression, metabolism, and electrical activity in vitro. In vivo, the brain is unique in its structural and functional organization, and the interactions and communication between different brain areas are essential components of proper brain function. This fact and the observation that neurons from different areas of the brain exhibit unique behaviors in vitro underline the importance of establishing multiregional brain in vitro models. Therefore, we here developed a multiregional brain-on-a-chip and observed a reduction of overall firing activity, as well as altered amounts of astrocytes and specific neuronal cell types compared with separately cultured neurons. Furthermore, this multiregional model was used to study the effects of phencyclidine, a drug known to induce schizophrenia-like symptoms in vivo, on individual brain areas separately while monitoring downstream effects on interconnected regions. Overall, this work provides a comparison of cells from different brain regions in vitro and introduces a multiregional brain-on-a-chip that enables the development of unique disease models incorporating essential in vivo features. NEW & NOTEWORTHY Due to the scarcity of comparative data for cells from different brain regions in vitro, we demonstrated that neurons isolated from distinct brain areas exhibit unique behaviors in vitro. Moreover, in vivo proper brain function is dependent on the connection and communication of several brain regions, underlining the importance of developing multiregional brain in vitro models. We introduced a novel brain-on-a-chip model, implementing essential in vivo features, such as different brain areas and their functional connections. Copyright © 2017 the American Physiological Society.

Neurons derived from different brain regions are inherently different in vitro: a novel multiregional brain-on-a-chip

PubMed Central

Dauth, Stephanie; Maoz, Ben M.; Sheehy, Sean P.; Hemphill, Matthew A.; Murty, Tara; Macedonia, Mary Kate; Greer, Angie M.; Budnik, Bogdan

2017-01-01

Brain in vitro models are critically important to developing our understanding of basic nervous system cellular physiology, potential neurotoxic effects of chemicals, and specific cellular mechanisms of many disease states. In this study, we sought to address key shortcomings of current brain in vitro models: the scarcity of comparative data for cells originating from distinct brain regions and the lack of multiregional brain in vitro models. We demonstrated that rat neurons from different brain regions exhibit unique profiles regarding their cell composition, protein expression, metabolism, and electrical activity in vitro. In vivo, the brain is unique in its structural and functional organization, and the interactions and communication between different brain areas are essential components of proper brain function. This fact and the observation that neurons from different areas of the brain exhibit unique behaviors in vitro underline the importance of establishing multiregional brain in vitro models. Therefore, we here developed a multiregional brain-on-a-chip and observed a reduction of overall firing activity, as well as altered amounts of astrocytes and specific neuronal cell types compared with separately cultured neurons. Furthermore, this multiregional model was used to study the effects of phencyclidine, a drug known to induce schizophrenia-like symptoms in vivo, on individual brain areas separately while monitoring downstream effects on interconnected regions. Overall, this work provides a comparison of cells from different brain regions in vitro and introduces a multiregional brain-on-a-chip that enables the development of unique disease models incorporating essential in vivo features. NEW & NOTEWORTHY Due to the scarcity of comparative data for cells from different brain regions in vitro, we demonstrated that neurons isolated from distinct brain areas exhibit unique behaviors in vitro. Moreover, in vivo proper brain function is dependent on the connection and communication of several brain regions, underlining the importance of developing multiregional brain in vitro models. We introduced a novel brain-on-a-chip model, implementing essential in vivo features, such as different brain areas and their functional connections. PMID:28031399

ISSLS PRIZE IN BIOENGINEERING SCIENCE 2018: dynamic imaging of degenerative spondylolisthesis reveals mid-range dynamic lumbar instability not evident on static clinical radiographs.

PubMed

Dombrowski, Malcolm E; Rynearson, Bryan; LeVasseur, Clarissa; Adgate, Zach; Donaldson, William F; Lee, Joon Y; Aiyangar, Ameet; Anderst, William J

2018-04-01

Degenerative spondylolisthesis (DS) in the setting of symptomatic lumbar spinal stenosis is commonly treated with spinal fusion in addition to decompression with laminectomy. However, recent studies have shown similar clinical outcomes after decompression alone, suggesting that a subset of DS patients may not require spinal fusion. Identification of dynamic instability could prove useful for predicting which patients are at higher risk of post-laminectomy destabilization necessitating fusion. The goal of this study was to determine if static clinical radiographs adequately characterize dynamic instability in patients with lumbar degenerative spondylolisthesis (DS) and to compare the rotational and translational kinematics in vivo during continuous dynamic flexion activity in DS versus asymptomatic age-matched controls. Seven patients with symptomatic single level lumbar DS (6 M, 1 F; 66 ± 5.0 years) and seven age-matched asymptomatic controls (5 M, 2 F age 63.9 ± 6.4 years) underwent biplane radiographic imaging during continuous torso flexion. A volumetric model-based tracking system was used to track each vertebra in the radiographic images using subject-specific 3D bone models from high-resolution computed tomography (CT). In vivo continuous dynamic sagittal rotation (flexion/extension) and AP translation (slip) were calculated and compared to clinical measures of intervertebral flexion/extension and AP translation obtained from standard lateral flexion/extension radiographs. Static clinical radiographs underestimate the degree of AP translation seen on dynamic in vivo imaging (1.0 vs 3.1 mm; p = 0.03). DS patients demonstrated three primary motion patterns compared to a single kinematic pattern in asymptomatic controls when analyzing continuous dynamic in vivo imaging. 3/7 (42%) of patients with DS demonstrated aberrant mid-range motion. Continuous in vivo dynamic imaging in DS reveals a spectrum of aberrant motion with significantly greater kinematic heterogeneity than previously realized that is not readily seen on current clinical imaging. Level V data These slides can be retrieved under Electronic Supplementary Material.

Effect of Different Sampling Schedules on Results of Bioavailability and Bioequivalence Studies: Evaluation by Means of Monte Carlo Simulations.

PubMed

Kano, Eunice Kazue; Chiann, Chang; Fukuda, Kazuo; Porta, Valentina

2017-08-01

Bioavailability and bioequivalence study is one of the most frequently performed investigations in clinical trials. Bioequivalence testing is based on the assumption that 2 drug products will be therapeutically equivalent when they are equivalent in the rate and extent to which the active drug ingredient or therapeutic moiety is absorbed and becomes available at the site of drug action. In recent years there has been a significant growth in published papers that use in silico studies based on mathematical simulations to analyze pharmacokinetic and pharmacodynamic properties of drugs, including bioavailability and bioequivalence aspects. The goal of this study is to evaluate the usefulness of in silico studies as a tool in the planning of bioequivalence, bioavailability and other pharmacokinetic assays, e.g., to determine an appropriate sampling schedule. Monte Carlo simulations were used to define adequate blood sampling schedules for a bioequivalence assay comparing 2 different formulations of cefadroxil oral suspensions. In silico bioequivalence studies comparing different formulation of cefadroxil oral suspensions using various sampling schedules were performed using models. An in vivo study was conducted to confirm in silico results. The results of in silico and in vivo bioequivalence studies demonstrated that schedules with fewer sampling times are as efficient as schedules with larger numbers of sampling times in the assessment of bioequivalence, but only if T max is included as a sampling time. It was also concluded that in silico studies are useful tools in the planning of bioequivalence, bioavailability and other pharmacokinetic in vivo assays. © Georg Thieme Verlag KG Stuttgart · New York.

Comparison of red-shifted firefly luciferase Ppy RE9 and conventional Luc2 as bioluminescence imaging reporter genes for in vivo imaging of stem cells

NASA Astrophysics Data System (ADS)

Liang, Yajie; Walczak, Piotr; Bulte, Jeff W. M.

2012-01-01

One critical issue for noninvasive imaging of transplanted bioluminescent cells is the large amount of light absorption in tissue when emission wavelengths below 600 nm are used. Luciferase with a red-shifted spectrum can potentially bypass this limitation. We assessed and compared a mutant of firefly luciferase (Ppy RE9, PRE9) against the yellow luciferase luc2 gene for use in cell transplantation studies. C17.2 neural stem cells expressing PRE9-Venus and luc2-Venus were sorted by flow cytometry and assessed for bioluminescence in vitro in culture and in vivo after transplantation into the brain of immunodeficient Rag2-/- mice. We found that the luminescence from PRE9 was stable, with a peak emission at 620 nm, shifted to the red compared to that of luc2. The emission peak for PRE9 was pH-independent, in contrast to luc2, and much less affected by tissue absorbance compared to that of luc2. However, the total emitted light radiance from PRE9 was substantially lower than that of luc2, both in vitro and in vivo. We conclude that PRE9 has favorable properties as compared to luc2 in terms of pH independence, red-shifted spectrum, tissue light penetration, and signal quantification, justifying further optimization of protein expression and enzymatic activity.

Comparative study of 64Cu/NOTA-[D-Tyr6,βAla11,Thi13,Nle14]BBN(6-14) monomer and dimers for prostate cancer PET imaging

PubMed Central

2012-01-01

Background Gastrin-releasing peptide receptors [GRPR] are highly over-expressed in multiple cancers and have been studied as a diagnostic target. Multimeric gastrin-releasing peptides are expected to have enhanced tumor uptake and affinity for GRPR. In this study, a 64Cu-labeled 1,4,7-triazacyclononane-1,4,7-triacetic acid [NOTA]-monomer and two NOTA-dimers of [D-Tyr6,βAla11, Thi13, Nle14]bombesin(6-14) ] [BBN(6-14)] were compared. Methods Monomeric and dimeric peptides were synthesized on solid phase support and radiolabeled with 64Cu. NOTA-dimer 1 consists of asymmetrically linked BBN(6-14), while NOTA-dimer 2 has similar spacer between the two BBN(6-14) ligands and the chelator. In vitro GRPR-binding affinities were determined with competitive binding assays on PC3 human prostate cancer cells. In vivo stability and biodistribution of radiolabeled compounds were assessed in Balb/c mice. Cellular uptake and efflux were measured with radiolabeled NOTA-monomer and NOTA-dimer 2 on PC3 cells for up to 4 h. In vivo biodistribution kinetics were measured in PC3 tumor-bearing Balb/c nude mice by μ-positron emission tomography [μPET] imaging and confirmed by dissection and counting. Results NOTA-monomer, NOTA-dimers 1 and 2 were prepared with purity of 99%. The inhibition constants of the three BBN peptides were comparable and in the low nanomolar range. All 64Cu-labeled peptides were stable up to 24 h in mouse plasma and 1 h in vivo. 64Cu/NOTA-dimer 2 featuring a longer spacer between the two BBN(6-14) ligands is a more potent GRPR-targeting probe than 64Cu/NOTA-dimer 1. PC3 tumor uptake profiles are slightly different for 64Cu/NOTA-monomer and 64Cu/NOTA-dimer 2; the monomeric BBN-peptide tracer exhibited higher tumor uptake during the first 0.5 h and a fast renal clearance resulting in higher tumor-to-muscle ratio when compared to 64Cu/NOTA-dimer 2. The latter exhibited higher tumor-to-blood ratio and was retained longer at the tumor site when compared to 64Cu/NOTA-monomer. Lower ratios of tumor-to-blood and tumor-to-muscle in blocking experiments showed GRPR-dependant tumor uptake for both tracers. Conclusion Both 64Cu/NOTA-monomer and 64Cu/NOTA-dimer 2 are suitable for detecting GRPR-positive prostate cancer in vivo by PET. Tumor retention was improved in vivo with 64Cu/NOTA-dimer 2 by applying polyvalency effect and/or statistical rebinding. PMID:22333272

Comparative study of 64Cu/NOTA-[D-Tyr6,βAla11,Thi13,Nle14]BBN(6-14) monomer and dimers for prostate cancer PET imaging.

PubMed

Fournier, Patrick; Dumulon-Perreault, Véronique; Ait-Mohand, Samia; Langlois, Réjean; Bénard, François; Lecomte, Roger; Guérin, Brigitte

2012-02-14

Gastrin-releasing peptide receptors [GRPR] are highly over-expressed in multiple cancers and have been studied as a diagnostic target. Multimeric gastrin-releasing peptides are expected to have enhanced tumor uptake and affinity for GRPR. In this study, a 64Cu-labeled 1,4,7-triazacyclononane-1,4,7-triacetic acid [NOTA]-monomer and two NOTA-dimers of [D-Tyr6,βAla11, Thi13, Nle14]bombesin(6-14) ] [BBN(6-14)] were compared. Monomeric and dimeric peptides were synthesized on solid phase support and radiolabeled with 64Cu. NOTA-dimer 1 consists of asymmetrically linked BBN(6-14), while NOTA-dimer 2 has similar spacer between the two BBN(6-14) ligands and the chelator. In vitro GRPR-binding affinities were determined with competitive binding assays on PC3 human prostate cancer cells. In vivo stability and biodistribution of radiolabeled compounds were assessed in Balb/c mice. Cellular uptake and efflux were measured with radiolabeled NOTA-monomer and NOTA-dimer 2 on PC3 cells for up to 4 h. In vivo biodistribution kinetics were measured in PC3 tumor-bearing Balb/c nude mice by μ-positron emission tomography [μPET] imaging and confirmed by dissection and counting. NOTA-monomer, NOTA-dimers 1 and 2 were prepared with purity of 99%. The inhibition constants of the three BBN peptides were comparable and in the low nanomolar range. All 64Cu-labeled peptides were stable up to 24 h in mouse plasma and 1 h in vivo. 64Cu/NOTA-dimer 2 featuring a longer spacer between the two BBN(6-14) ligands is a more potent GRPR-targeting probe than 64Cu/NOTA-dimer 1. PC3 tumor uptake profiles are slightly different for 64Cu/NOTA-monomer and 64Cu/NOTA-dimer 2; the monomeric BBN-peptide tracer exhibited higher tumor uptake during the first 0.5 h and a fast renal clearance resulting in higher tumor-to-muscle ratio when compared to 64Cu/NOTA-dimer 2. The latter exhibited higher tumor-to-blood ratio and was retained longer at the tumor site when compared to 64Cu/NOTA-monomer. Lower ratios of tumor-to-blood and tumor-to-muscle in blocking experiments showed GRPR-dependant tumor uptake for both tracers. Both 64Cu/NOTA-monomer and 64Cu/NOTA-dimer 2 are suitable for detecting GRPR-positive prostate cancer in vivo by PET. Tumor retention was improved in vivo with 64Cu/NOTA-dimer 2 by applying polyvalency effect and/or statistical rebinding.

Evaluation of the In Vivo and Ex Vivo Binding of Novel BC1 Cannabinoid Receptor Radiotracers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, A.; Gatley, J.; Gifford, A.

The primary active ingredient of marijuana, 9-tetrahydrocannabinol, exerts its psychoactive effects by binding to cannabinoid CB1 receptors. These receptors are found throughout the brain with high concentrations in the hippocampus and cerebellum. The current study was conducted to evaluate the binding of a newly developed putative cannabinoid antagonist, AM630, and a classical cannabinoid 8-tetrahydrocannabinol as potential PET and/or SPECT imaging agents for brain CB1 receptors. For both of these ligands in vivo and ex vivo studies in mice were conducted. AM630 showed good overall brain uptake (as measure by %IA/g) and a moderately rapid clearance from the brain with amore » half-clearance time of approximately 30 minutes. However, AM630 did not show selective binding to CB1 cannabinoid receptors. Ex vivo autoradiography supported the lack of selective binding seen in the in vivo study. Similar to AM630, 8-tetrahydrocanibol also failed to show selective binding to CB1 receptor rich brain areas. The 8-tetrahydrocanibol showed moderate overall brain uptake and relatively slow brain clearance as compared to AM630. Further studies were done with AM2233, a cannabinoid ligand with a similar structure as AM630. These studies were done to develop an ex vivo binding assay to quantify the displacement of [131I]AM2233 binding by other ligands in Swiss-Webster and CB1 receptor knockout mice. By developing this assay we hoped to determine the identity of an unknown binding site for AM2233 present in the hippocampus of CB1 knockout mice. Using an approach based on incubation of brain slices prepared from mice given intravenous [131I]AM2233 in either the presence or absence of AM2233 (unlabelled) it was possible to demonstrate a significant AM2233-displacable binding in the Swiss-Webster mice. Future studies will determine if this assay is appropriate for identifying the unknown binding site for AM2233 in the CB1 knockout mice.« less

Robust labeling and comparative preclinical characterization of DOTA-TOC and DOTA-TATE.

PubMed

Velikyan, Irina; Xu, Hui; Nair, Manoj; Hall, Håkan

2012-07-01

Various radionuclide-labeled somatostatin analogues are used currently for diagnosis and therapy of neuroendocrine tumors. In particular, [68Ga]Ga-DOTA-TOC is commonly used for diagnosis, while [177Lu]Lu-DOTA-TATE is used for therapy. With the development of theranostics and personalized medicine where the imaging diagnosis is tailored to the subsequent radiotherapy, it is of paramount importance to investigate the relevance of the ligand exchange. The aim of this study was to compare binding capacity of [67/68Ga]Ga-DOTA-TOC ([67/68Ga]Ga-N-(4,7,10-(tris(carboxymethyl)-1,4,7,10-tetraazacyclododecan-1-yl)acetyl-D-Phe-c[Cys-D-Tyr-Trp-Lys-Thr-Cys]-Thr(ol)) and [67/68Ga]Ga-DOTA-TATE ([67/68Ga]Ga-N-(4,7,10-(tris(carboxymethyl)-1,4,7,10-tetraazacyclododecan-1-yl)acetyl-D-Phe-c[Cys-D-Tyr-Trp-Lys-Thr-Cys]-Thr) in vitro in monkey brain cryosections and in vivo in the rat, where, in contrast to transfected cell lines, there is a heterogeneous distribution of somatostatin receptor (SSTR) subtypes. The influence of various production methods of [68Ga]Ga-DOTA-TOC and [68Ga]Ga-DOTA-TATE on the biological performance of the tracers was also studied. [67Ga]Ga-DOTA-TOC, [68Ga]Ga-DOTA-TOC, [67Ga]Ga-DOTA-TATE and [68Ga]Ga-DOTA-TATE were synthesized including preconcentration and purification of the generator eluate. The binding of the radioligands was assessed in vitro using autoradiography on cryosections of Rhesus monkey brains and in vivo/ex vivo using organ distribution studies in rats. The tracer production method was improved in terms of higher robustness, simplification and good manufacturing practice (GMP) relevance. The synthesis variation did not influence the biological performance of the tracers. There was no statistically significant difference observed in the binding of [67/68Ga]Ga-DOTA-TOC and [67/68Ga]Ga-DOTA-TATE either in brain cortex in vitro or in rat biodistribution and uptake in SSTR-positive tissues such as pancreas, adrenals and pituitary. The uptake in these organs was precluded by the excess of octreotide (Sandostatin). The 10-fold higher affinity to SSTR2 of DOTA-TATE as compared to DOTA-TOC known from studies in transfected cells was reflected in a slightly more intense binding of [67/68Ga]Ga-DOTA-TATE than of [67/68Ga]Ga-DOTA-TOC in the monkey brain sections in vitro, but not in vivo in the rat. A robust 68Ga-labeling method was introduced. The difference in the uptake of [67/68Ga]Ga-DOTA-TOC and [67/68Ga]Ga-DOTA-TATE in SSTR2-positive organs was not statistically significant either in vitro in tissue studies or in vivo/ex vivo in rat experiments. The results indicate that the more complex environment in vitro and in vivo diminishes the difference observed in transfected cell line binding. Copyright © 2012 Elsevier Inc. All rights reserved.

Improved oral bioavailability of poorly water-soluble indirubin by a supersaturatable self-microemulsifying drug delivery system

PubMed Central

Chen, Zhi-Qiang; Liu, Ying; Zhao, Ji-Hui; Wang, Lan; Feng, Nian-Ping

2012-01-01

Background Indirubin, isolated from the leaves of the Chinese herb Isatis tinctoria L, is a protein kinase inhibitor and promising antitumor agent. However, the poor water solubility of indirubin has limited its application. In this study, a supersaturatable self-microemulsifying drug delivery system (S-SMEDDS) was developed to improve the oral bioavailability of indirubin. Methods A prototype S-SMEDDS was designed using solubility studies and phase diagram construction. Precipitation inhibitors were selected from hydrophilic polymers according to their crystallization-inhibiting capacity through in vitro precipitation tests. In vitro release of indirubin from S-SMEDDS was examined to investigate its likely release behavior in vivo. The in vivo bioavailability of indirubin from S-SMEDDS and from SMEDDS was compared in rats. Results The prototype formulation of S-SMEDDS comprised Maisine™ 35-1:Cremophor® EL:Transcutol® P (15:40:45, w/w/w). Polyvinylpyrrolidone K17, a hydrophilic polymer, was used as a precipitation inhibitor based on its better crystallization-inhibiting capacity compared with polyethylene glycol 4000 and hydroxypropyl methylcellulose. In vitro release analysis showed more rapid drug release from S-SMEDDS than from SMEDDS. In vivo bioavailability analysis in rats indicated that improved oral absorption was achieved and that the relative bioavailability of S-SMEDDS was 129.5% compared with SMEDDS. Conclusion The novel S-SMEDDS developed in this study increased the dissolution rate and improved the oral bioavailability of indirubin in rats. The results suggest that S-SMEDDS is a superior means of oral delivery of indirubin. PMID:22403491

NOTE: Clinical application of a OneDose™ MOSFET for skin dose measurements during internal mammary chain irradiation with high dose rate brachytherapy in carcinoma of the breast

NASA Astrophysics Data System (ADS)

Kinhikar, Rajesh A.; Sharma, Pramod K.; Tambe, Chandrashekhar M.; Mahantshetty, Umesh M.; Sarin, Rajiv; Deshpande, Deepak D.; Shrivastava, Shyam K.

2006-07-01

In our earlier study, we experimentally evaluated the characteristics of a newly designed metal oxide semiconductor field effect transistor (MOSFET) OneDose™ in-vivo dosimetry system for Ir-192 (380 keV) energy and the results were compared with thermoluminescent dosimeters (TLDs). We have now extended the same study to the clinical application of this MOSFET as an in-vivo dosimetry system. The MOSFET was used during high dose rate brachytherapy (HDRBT) of internal mammary chain (IMC) irradiation for a carcinoma of the breast. The aim of this study was to measure the skin dose during IMC irradiation with a MOSFET and a TLD and compare it with the calculated dose with a treatment planning system (TPS). The skin dose was measured for ten patients. All the patients' treatment was planned on a PLATO treatment planning system. TLD measurements were performed to compare the accuracy of the measured results from the MOSFET. The mean doses measured with the MOSFET and the TLD were identical (0.5392 Gy, 15.85% of the prescribed dose). The mean dose was overestimated by the TPS and was 0.5923 Gy (17.42% of the prescribed dose). The TPS overestimated the skin dose by 9% as verified by the MOSFET and TLD. The MOSFET provides adequate in-vivo dosimetry for HDRBT. Immediate readout after irradiation, small size, permanent storage of dose and ease of use make the MOSFET a viable alternative for TLDs.

Clinical application of a OneDose MOSFET for skin dose measurements during internal mammary chain irradiation with high dose rate brachytherapy in carcinoma of the breast.

PubMed

Kinhikar, Rajesh A; Sharma, Pramod K; Tambe, Chandrashekhar M; Mahantshetty, Umesh M; Sarin, Rajiv; Deshpande, Deepak D; Shrivastava, Shyam K

2006-07-21

In our earlier study, we experimentally evaluated the characteristics of a newly designed metal oxide semiconductor field effect transistor (MOSFET) OneDose in-vivo dosimetry system for Ir-192 (380 keV) energy and the results were compared with thermoluminescent dosimeters (TLDs). We have now extended the same study to the clinical application of this MOSFET as an in-vivo dosimetry system. The MOSFET was used during high dose rate brachytherapy (HDRBT) of internal mammary chain (IMC) irradiation for a carcinoma of the breast. The aim of this study was to measure the skin dose during IMC irradiation with a MOSFET and a TLD and compare it with the calculated dose with a treatment planning system (TPS). The skin dose was measured for ten patients. All the patients' treatment was planned on a PLATO treatment planning system. TLD measurements were performed to compare the accuracy of the measured results from the MOSFET. The mean doses measured with the MOSFET and the TLD were identical (0.5392 Gy, 15.85% of the prescribed dose). The mean dose was overestimated by the TPS and was 0.5923 Gy (17.42% of the prescribed dose). The TPS overestimated the skin dose by 9% as verified by the MOSFET and TLD. The MOSFET provides adequate in-vivo dosimetry for HDRBT. Immediate readout after irradiation, small size, permanent storage of dose and ease of use make the MOSFET a viable alternative for TLDs.

Development of an in vitro cell culture model to study milk to plasma ratios of therapeutic drugs.

PubMed

Athavale, Maithili A; Maitra, Anurupa; Patel, Shahnaz; Bhate, Vijay R; Toddywalla, Villi S

2013-01-01

To create an in vitro cell culture model to predict the M/P (concentration of drug in milk/concentration in maternal plasma) ratios of therapeutic drugs viz. rifampicin, theophylline, paracetamol, and aspirin. An in vitro cell culture model using CIT3 cells (mouse mammary epithelial cells) was created by culturing the cells on transwells. The cells formed an integral monolayer, allowing only transcellular transport as it happens in vivo. Functionality of the cells was confirmed through scanning electron microscopy. Time wise transfer of the study drugs from plasma to milk was studied and compared with actual (in vivo) M/P ratios obtained at reported tmax for the respective drugs. The developed model mimicked two important intrinsic factors of mammary epithelial cells viz. secretory and tight-junction properties and also the passive route of drug transport. The in vitro M/P ratios at reported tmax were 0.23, 0.61, 0.87, and 0.03 respectively, for rifampicin, theophylline, paracetamol, and salicylic acid as compared to 0.29, 0.65, 0.65, and 0.22, respectively, in vitro. Our preliminary effort to develop an in vitro physiological model showed promising results. Transfer rate of the drugs using the developed model compared well with the transfer potential seen in vivo except for salicylic acid, which was transferred in far lower concentration in vitro. The model has a potential to be developed as a non-invasive alternative to the in vitro technique for determining the transfer of therapeutic drugs into breast milk.

In vivo determination of multiple indices of periodontal inflammation by optical spectroscopy

PubMed Central

Liu, KZ; Xiang, XM; Man, A; Sowa, MG; Cholakis, N; Ghiabi, E; Singer, DL; Scott, DA

2008-01-01

Background and Objective Visible – near infrared (optical) spectroscopy can be used to measure regional tissue hemodynamics and edema and, therefore, may represent an ideal tool with which to non-invasively study periodontal inflammation. The study objective was to evaluate the ability of optical spectroscopy to simultaneously determine multiple inflammatory indices (tissue oxygenation, total tissue hemoglobin, deoxyhemoglobin, oxygenated hemoglobin, and tissue edema) in periodontal tissues in vivo. Material and Methods Spectra were obtained, processed, and evaluated from healthy, gingivitis, and periodontitis sites (n = 133) using a portable optical – near infrared spectrometer. A modified Beer-Lambert unmixing model that incorporates a nonparametric scattering loss function was used to determine the relative contribution of each inflammatory component to the overall spectrum. Results Optical spectroscopy was harnessed to successfully generate complex inflammatory profiles in periodontal tissues. Tissue oxygenation at periodontitis sites was significantly decreased (p<0.05) compared to gingivitis and healthy controls. This is largely due to an increase in deoxyhemoglobin in the periodontitis sites compared to healthy (p<0.01) and gingivitis (p=0.05) sites. Tissue water content per se showed no significant difference between the sites but a water index associated with tissue electrolyte levels and temperature differed was significantly between periodontitis sites when compared to both healthy and gingivitis sites (p<0.03). Conclusion This study establishes that optical spectroscopy can simultaneously determine multiple inflammatory indices directly in the periodontal tissues in vivo. Visible - near infrared spectroscopy has the potential to be developed into a simple, reagent-free, user friendly, chair-side, site-specific, diagnostic and prognostic test for periodontitis. PMID:18973538

In Vivo Anticancer Efficacy and Toxicity Studies of a Novel Polymer Conjugate N-Acetyl Glucosamine (NAG)-PEG-Doxorubicin for Targeted Cancer Therapy.

PubMed

Pawar, Smita; Mahajan, Ketan; Vavia, Pradeep

2017-11-01

A novel polymer-drug conjugate, polyethylene glycol-N-(acetyl)-glucosamine-doxorubicin (PEG-NAG-DOX) was evaluated in this study for its in vivo potential for treatment of tumours demonstrating improved efficacy and reduced toxicity. The proposed polymer-drug conjugate comprised of polyethylene glycol-maleimide (mPEG-MAL, 30000 Da) as a carrier, doxorubicin (DOX) as an anticancer drug and N-acetyl glucosamine (NAG) as a targeting moiety as well as penetration enhancer. Doxorubicin has a potent and promising anticancer activity; however, severe cardiotoxicity limits its application in cancer treatment. By modifying DOX in PEG-NAG-DOX prodrug conjugate, we aimed to eliminate this limitation. In vivo anticancer efficacy of the conjugate was evaluated using BDF mice-induced skin melanoma model by i.v. administration of DOX conjugates. Anticancer efficacy studies were done by comparing tumour volume, body weight, organ index and percent survival rate of the animals. Tumour suppression achieved by PEG-NAG-DOX at the cumulative dose of 7.5 mg/kg was two-fold better than that achieved by DOX solution. Also, the survival rate for PEG-NAG-DOX conjugate was >70% as compared to <50% survival rate for DOX solution. In addition, toxicity studies and histopathological studies revealed that while maintaining its cytotoxicity towards tumour cells, PEG-NAG-DOX conjugate showed no toxicities to major organs. Therefore, PEG-NAG-DOX conjugate can be suggested as a desirable candidate for targeted cancer therapy.

Formulation and evaluation of an in situ gel forming system for controlled delivery of triptorelin acetate.

PubMed

Abashzadeh, Sh; Dinarvand, R; Sharifzadeh, M; Hassanzadeh, G; Amini, M; Atyabi, F

2011-11-20

The novel physical hydrogels composed of chitosan or its water soluble derivatives such as carboxymethyl chitosan (CMCh) and sodium carboxymethyl chitosan (NaCMCh) and opened ring polyvinyl pyrrolidone (OP-PVP) were used as a controlled delivery system for triptorelin acetate, a luteinizing-releasing hormone agonist. The in situ gel forming system designed according to physical interactions such as chains entanglements and hydrophilic attractions especially h-bonds of chitosan and/or NaCMCh and OR-PVP. In order to increase in situ gel forming rate the chitosan microspheres prepared through spray drying technique. The chitosan or NaCMCh/OR-PVP blends prepared at different ratios (0.05, 0.10, 0.12, 0.16, 0.20 and 0.24) and suspended in sesame oil as non-aqueous vehicle at different solid content (10-30%). The suitable ratio of polymers with faster in situ gel forming rate was selected for in vivo studies. The gel formation and drug release from the system was evaluated both in vitro and in vivo. In vitro and in vivo results were compared with Diphereline SR 3.75mg, a commercially available controlled delivery system of triptorelin. In vitro release studies showed a sustained release profile for about 192h with first order kinetics. In vivo studies on male rats by determination of serum testosterone were confirmed the acceptable performance of in situ gel forming system compared with Diphereline SR in decreasing the serum testosterone level for 35days, demonstrating the potential of the novel in situ gel forming system for controlled delivery of peptides. Copyright © 2011 Elsevier B.V. All rights reserved.

In vitro and in vivo evaluation of a water-in-oil microemulsion system for enhanced peptide intestinal delivery.

PubMed

Liu, Dongyun; Kobayashi, Taku; Russo, Steven; Li, Fengling; Plevy, Scott E; Gambling, Todd M; Carson, Johnny L; Mumper, Russell J

2013-01-01

Peptide and protein drugs have become the new generation of therapeutics, yet most of them are only available as injections, and reports on oral local intestinal delivery of peptides and proteins are quite limited. The aim of this work was to develop and evaluate a water-in-oil (w/o) microemulsion system in vitro and in vivo for local intestinal delivery of water-soluble peptides after oral administration. A fluorescent labeled peptide, 5-(and-6)-carboxytetramethylrhodamine labeled HIV transactivator protein TAT (TAMRA-TAT), was used as a model peptide. Water-in-oil microemulsions consisting of Miglyol 812, Capmul MCM, Tween 80, and water were developed and characterized in terms of appearance, viscosity, conductivity, morphology, and particle size analysis. TAMRA-TAT was loaded and its enzymatic stability was assessed in modified simulated intestinal fluid (MSIF) in vitro. In in vivo studies, TAMRA-TAT intestinal distribution was evaluated using fluorescence microscopy after TAMRA-TAT microemulsion, TAMRA-TAT solution, and placebo microemulsion were orally gavaged to mice. The half-life of TAMRA-TAT in microemulsion was enhanced nearly three-fold compared to that in the water solution when challenged by MSIF. The treatment with TAMRA-TAT microemulsion after oral administration resulted in greater fluorescence intensity in all intestine sections (duodenum, jejunum, ileum, and colon) compared to TAMRA-TAT solution or placebo microemulsion. The in vitro and in vivo studies together suggested TAMRA-TAT was better protected in the w/o microemulsion in an enzyme-containing environment, suggesting that the w/o microemulsions developed in this study may serve as a potential delivery vehicle for local intestinal delivery of peptides or proteins after oral administration.

A study of quantification of aortic compliance in mice using radial acquisition phase contrast MRI

NASA Astrophysics Data System (ADS)

Zhao, Xuandong

Spatiotemporal changes in blood flow velocity measured using Phase contrast Magnetic Resonance Imaging (MRI) can be used to quantify Pulse Wave Velocity (PWV) and Wall Shear Stress (WSS), well known indices of vessel compliance. A study was conducted to measure the PWV in the aortic arch in young healthy children using conventional phase contrast MRI and a post processing algorithm that automatically track the peak velocity in phase contrast images. It is shown that the PWV calculated using peak velocity-time data has less variability compared to that using mean velocity and flow. Conventional MR data acquisition techniques lack both the spatial and temporal resolution needed to accurately calculate PWV and WSS in in vivo studies using transgenic animal models of arterial diseases. Radial k-space acquisition can improve both spatial and temporal resolution. A major part of this thesis was devoted to developing technology for Radial Phase Contrast Magnetic Resonance (RPCMR) cine imaging on a 7 Tesla Animal scanner. A pulse sequence with asymmetric radial k-space acquisition was designed and implemented. Software developed to reconstruct the RPCMR images include gridding, density compensation and centering of k-Space that corrects the image ghosting introduced by hardware response time. Image processing software was developed to automatically segment the vessel lumen and correct for phase offset due to eddy currents. Finally, in vivo and ex vivo aortic compliance measurements were conducted in a well-established mouse model for atherosclerosis: Apolipoprotein E-knockout (ApoE-KO). Using RPCMR technique, a significantly higher PWV value as well as a higher average WSS was detected among 9 months old ApoE-KO mice compare to in wild type mice. A follow up ex-vivo test of tissue elasticity confirmed the impaired distensibility of aortic arteries among ApoE-KO mice.

Applying Simulated In Vivo Motions to Measure Human Knee and ACL Kinetics

PubMed Central

Herfat, Safa T.; Boguszewski, Daniel V.; Shearn, Jason T.

2013-01-01

Patients frequently experience anterior cruciate ligament (ACL) injuries but current ACL reconstruction strategies do not restore the native biomechanics of the knee, which can contribute to the early onset of osteoarthritis in the long term. To design more effective treatments, investigators must first understand normal in vivo knee function for multiple activities of daily living (ADLs). While the 3D kinematics of the human knee have been measured for various ADLs, the 3D kinetics cannot be directly measured in vivo. Alternatively, the 3D kinetics of the knee and its structures can be measured in an animal model by simulating and applying subject-specific in vivo joint motions to a joint using robotics. However, a suitable biomechanical surrogate should first be established. This study was designed to apply a simulated human in vivo motion to human knees to measure the kinetics of the human knee and ACL. In pursuit of establishing a viable biomechanical surrogate, a simulated in vivo ovine motion was also applied to human knees to compare the loads produced by the human and ovine motions. The motions from the two species produced similar kinetics in the human knee and ACL. The only significant difference was the intact knee compression force produced by the two input motions. PMID:22227973

Comparison of cytotoxicity in vitro and irritation in vivo for aqueous and oily solutions of surfactants.

PubMed

Czajkowska-Kośnik, Anna; Wolska, Eliza; Chorążewicz, Juliusz; Sznitowska, Małgorzata

2015-01-01

The in vivo model on rabbit eyes and the in vitro cytotoxicity on fibroblasts were used to compare irritation effect of aqueous and oily (Miglyol 812) solutions of surfactants. Tween 20, Tween 80 and Cremophor EL were tested in different concentrations (0.1, 1 or 5%) and the in vitro test demonstrated that surfactants in oil are less cytotoxic than in aqueous solutions. In the in vivo study, the aqueous solutions of surfactants were characterized as non-irritant while small changes in conjunctiva were observed after application the oily solutions of surfactants and the preparations were classified as slightly irritant, however this effect was similar when Miglyol was applied alone. In conclusion, it is reported that the MTT assay does not correlate well with the Draize scores.

In vivo recordings of brain activity using organic transistors

PubMed Central

Khodagholy, Dion; Doublet, Thomas; Quilichini, Pascale; Gurfinkel, Moshe; Leleux, Pierre; Ghestem, Antoine; Ismailova, Esma; Hervé, Thierry; Sanaur, Sébastien; Bernard, Christophe; Malliaras, George G.

2013-01-01

In vivo electrophysiological recordings of neuronal circuits are necessary for diagnostic purposes and for brain-machine interfaces. Organic electronic devices constitute a promising candidate because of their mechanical flexibility and biocompatibility. Here we demonstrate the engineering of an organic electrochemical transistor embedded in an ultrathin organic film designed to record electrophysiological signals on the surface of the brain. The device, tested in vivo on epileptiform discharges, displayed superior signal-to-noise ratio due to local amplification compared with surface electrodes. The organic transistor was able to record on the surface low-amplitude brain activities, which were poorly resolved with surface electrodes. This study introduces a new class of biocompatible, highly flexible devices for recording brain activity with superior signal-to-noise ratio that hold great promise for medical applications. PMID:23481383

In vivo recordings of brain activity using organic transistors.

PubMed

Khodagholy, Dion; Doublet, Thomas; Quilichini, Pascale; Gurfinkel, Moshe; Leleux, Pierre; Ghestem, Antoine; Ismailova, Esma; Hervé, Thierry; Sanaur, Sébastien; Bernard, Christophe; Malliaras, George G

2013-01-01

In vivo electrophysiological recordings of neuronal circuits are necessary for diagnostic purposes and for brain-machine interfaces. Organic electronic devices constitute a promising candidate because of their mechanical flexibility and biocompatibility. Here we demonstrate the engineering of an organic electrochemical transistor embedded in an ultrathin organic film designed to record electrophysiological signals on the surface of the brain. The device, tested in vivo on epileptiform discharges, displayed superior signal-to-noise ratio due to local amplification compared with surface electrodes. The organic transistor was able to record on the surface low-amplitude brain activities, which were poorly resolved with surface electrodes. This study introduces a new class of biocompatible, highly flexible devices for recording brain activity with superior signal-to-noise ratio that hold great promise for medical applications.

Validation of an in vitro model for predicting rumen and total-tract fiber digestibility in dairy cows fed corn silages with different in vitro neutral detergent fiber digestibilities at 2 levels of dry matter intake.

PubMed

Lopes, F; Cook, D E; Combs, D K

2015-01-01

An in vivo study was performed to validate an in vitro procedure that predicts rate of fiber digestion and total-tract neutral detergent fiber digestibility (TTNDFD). Two corn silages that differed in fiber digestibility were used in this trial. The corn silage with lower fiber digestibility (LFDCS) had the TTNDFD prediction of 36.0% of total NDF, whereas TTNDFD for the corn silage with higher fiber digestibility (HFDCS) was 44.9% of total neutral detergent fiber (NDF). Two diets (1 with LFDCS and 1 with HFDCS) were formulated and analyzed using the in vitro assay to predict the TTNDFD and rumen potentially digestible NDF (pdNDF) digestion rate. Similar diets were fed to 8 ruminally cannulated, multiparous, high-producing dairy cows in 2 replicated 4×4 Latin squares with 21-d periods. A 2×2 factorial arrangement of treatments was used with main effects of intake (restricted to approximately 90% of ad libitum intake vs. ad libitum) and corn silage of different fiber digestibility. Treatments were restricted and ad libitum LFDCS as well as restricted and ad libitum HFDCS. The input and output values predicted from the in vitro model were compared with in vivo measurements. The pdNDF intake predicted by the in vitro model was similar to pdNDF intake observed in vivo. Also, the pdNDF digestion rate predicted in vitro was similar to what was observed in vivo. The in vitro method predicted TTNDFD of 50.2% for HFDCS and 42.9% for LFDCS as a percentage of total NDF in the diets, whereas the in vivo measurements of TTNDFD averaged 50.3 and 48.6% of total NDF for the HFDCS and LFDCS diets, respectively. The in vitro TTNDFD assay predicted total-tract NDF digestibility of HFDCS diets similar to the digestibility observed in vivo, but for LFDCS diets the assay underestimated the digestibility compared with in vivo. When the in vitro and in vivo measurements were compared without intake effect (ad libitum and restricted) considering only diet effect of silage fiber digestibility (HFDCS and LFDCS), no differences were observed between methods. These values suggest that our in vitro TTNDFD model could be used to predicted rate of fiber digestion and NDF digestibility for dairy cattle. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Noninvasive laser vasectomy

NASA Astrophysics Data System (ADS)

Cilip, Christopher Michael

Development of a noninvasive vasectomy technique may eliminate male fear of complications (incision, bleeding, infection, and scrotal pain) and result in a more popular procedure. These studies build off previous studies that report the ability to thermally target tissue substructures with near infrared laser radiation while maintaining a healthy superficial layer of tissue through active surface cooling. Initial studies showed the ability to increase the working depth compared to that of common dermatological procedures and the translation into an ex vivo canine model targeting the vas deferens in a noninvasive laser vasectomy. Laser and cooling parameter optimization was required to determine the best possible wavelength for a safe transition to an in vivo canine model. Optical clearing agents were investigated as a mechanism to decrease tissue scattering during in vivo procedures to increase optical penetration depth and reduce the overall power required. Optical and thermal computer models were developed to determine the efficacy for a successful transition into a human model. Common clinical imaging modalities (ultrasound, high frequency ultrasound, and optical coherence tomography) were tested as possible candidates for real-time imaging feedback to determine surgical success. Finally, a noninvasive laser vasectomy prototype clamp incorporating laser, cooling, and control in a single package was designed and tested in vivo. Occlusion of the canine vas deferens able to withstand physiological burst pressures measured postoperative was shown during acute and chronic studies. This procedure is ready for azoospermia and recanalization studies in a clinical setting.

A comparative histological study of alginate beads as a promising controlled release delivery for mefenamic acid.

PubMed

Sevgi, Ferhan; Kaynarsoy, Buket; Ozyazici, Mine; Pekcetin, Cetin; Ozyurt, Dogan

2008-01-01

The new mefenamic acid-alginate bead formulation prepared by ionotropic gelation method using 3 x 2(2) factorial design has shown adequate controlled release properties in vitro. In the present study, the irritation effects of mefenamic acid (MA), a prominent non-steroidal anti-inflammatory (NSAI) drug, were evaluated on rat gastric and duodenal mucosa when suspended in 0.5% (w/v) sodiumcarboxymethylcellulose (NaCMC) solution and loaded in alginate beads. Wistar albino rats weighing 200 +/- 50 g were used during in vivo animal studies. In this work, biodegradable controlled release MA beads and free MA were evaluated according to the degree of gastric or duodenal damage following oral administration in rats. The gastric and duodenal mucosa was examined for any haemorrhagic changes. Formulation code A10 showing both Case II transport and zero order drug release and t(50) % value of 5.22 h was chosen for in vivo animal studies. For in vivo trials, free MA (100 mgkg(-1)), blank and MA (100 mgkg(-1)) loaded alginate beads (formulation code A10) were suspended in 0.5% (w/v) NaCMC solution and each group was given to six rats orally by gavage. NaCMC solution was used as a control in experimental studies. In vivo data showed that the administration of MA in alginate beads prevented the gastric lesions.

Fluid viscosity affects the fragmentation and inertial cavitation threshold of lipid encapsulated microbubbles

PubMed Central

Helfield, Brandon; Black, John J.; Qin, Bin; Pacella, John; Chen, Xucai; Villanueva, Flordeliza S.

2015-01-01

Ultrasound and microbubble optimization studies for therapeutic applications are often conducted in water/saline, with a fluid viscosity of 1 cP. In an in vivo context, microbubbles are situated in blood, a more viscous fluid (~4 cP). In this study, ultra-high speed microscopy and passive cavitation approaches were employed to investigate the effect of fluid viscosity on microbubble behavior at 1 MHz subject to high pressures (0.25 – 2 MPa). The propensity for individual microbubble (n=220) fragmentation was shown to significantly decrease in 4 cP fluid as compared to 1 cP fluid, despite achieving similar maximum radial excursions. Microbubble populations diluted in 4 cP fluid exhibited decreased wideband emissions (up to 10.2 times), and increasingly distinct harmonic emission peaks (e.g. ultraharmonic) with increasing pressure as compared to 1 cP fluid. These results suggest that in vitro studies should consider an evaluation using physiologic viscosity perfusate before transitioning to in vivo evaluations. PMID:26674676

3D printed alendronate-releasing poly(caprolactone) porous scaffolds enhance osteogenic differentiation and bone formation in rat tibial defects.

PubMed

Kim, Sung Eun; Yun, Young-Pil; Shim, Kyu-Sik; Kim, Hak-Jun; Park, Kyeongsoon; Song, Hae-Ryong

2016-09-29

The aim of this study was to evaluate the in vitro osteogenic effects and in vivo new bone formation of three-dimensional (3D) printed alendronate (Aln)-releasing poly(caprolactone) (PCL) (Aln/PCL) scaffolds in rat tibial defect models. 3D printed Aln/PCL scaffolds were fabricated via layer-by-layer deposition. The fabricated Aln/PCL scaffolds had high porosity and an interconnected pore structure and showed sustained Aln release. In vitro studies showed that MG-63 cells seeded on the Aln/PCL scaffolds displayed increased alkaline phosphatase (ALP) activity and calcium content in a dose-dependent manner when compared with cell cultures in PCL scaffolds. In addition, in vivo animal studies and histologic evaluation showed that Aln/PCL scaffolds implanted in a rat tibial defect model markedly increased new bone formation and mineralized bone tissues in a dose-dependent manner compared to PCL-only scaffolds. Our results show that 3D printed Aln/PCL scaffolds are promising templates for bone tissue engineering applications.

P-gp Protein Expression and Transport Activity in Rodent Seizure Models and Human Epilepsy.

PubMed

Hartz, Anika M S; Pekcec, Anton; Soldner, Emma L B; Zhong, Yu; Schlichtiger, Juli; Bauer, Bjoern

2017-04-03

A cure for epilepsy is currently not available, and seizure genesis, seizure recurrence, and resistance to antiseizure drugs remain serious clinical problems. Studies show that the blood-brain barrier is altered in animal models of epilepsy and in epileptic patients. In this regard, seizures increase expression of blood-brain barrier efflux transporters such as P-glycoprotein (P-gp), which is thought to reduce brain uptake of antiseizure drugs, and thus, contribute to antiseizure drug resistance. The goal of the current study was to assess the viability of combining in vivo and ex vivo preparations of isolated brain capillaries from animal models of seizures and epilepsy as well as from patients with epilepsy to study P-gp at the blood-brain barrier. Exposing isolated rat brain capillaries to glutamate ex vivo upregulated P-gp expression to levels that were similar to those in capillaries isolated from rats that had status epilepticus or chronic epilepsy. Moreover, the fold-increase in P-gp protein expression seen in animal models is consistent with the fold-increase in P-gp observed in human brain capillaries isolated from patients with epilepsy compared to age-matched control individuals. Overall, the in vivo/ex vivo approach presented here allows detailed analysis of the mechanisms underlying seizure-induced changes of P-gp expression and transport activity at the blood-brain barrier. This approach can be extended to other blood-brain barrier proteins that might contribute to drug-resistant epilepsy or other CNS disorders as well.

Proliferation of CD4CD25Foxp3 regulatory T lymphocytes in ex vivo expanded ascitic fluid from primary and recurrent ovarian carcinoma.

PubMed

Lee, Shin Wha; Kim, Yong-Man; Lee, Ha-Young; Kim, Dae-Yeon; Kim, Jong-Hyeok; Nam, Joo-Hyun; Kim, Young-Tak

2010-03-01

Regulatory T lymphocytes evoke the immune tolerance by suppressing and inactivating cytotoxic T lymphocytes. The objective of this study was to compare the proportion of regulatory T lymphocytes, precisely defined as CD4(+)CD25(high+)Foxp3(+) T lymphocytes, in primary and recurrent ovarian carcinoma before and after ex vivo expansion of ascites with interleukin-2 (IL-2). Ascitic fluid samples were obtained from 26 patients with ovarian carcinoma. Lymphocytes were isolated from ascites and cell markers were analyzed by flow cytometry using anti-CD3/CD4/CD8/CD16/CD56/CD25 and anti-Foxp3 antibodies. Lymphocytes were incubated for 2 to 3 weeks and expanded ex vivo by IL-2 stimulation and their phenotypes were analyzed by flow cytometry. Following ex vivo expansion, ascitic fluid lymphocytes increased by a greater extent in the recurrent group than in the primary group. The proportion of ex vivo-expanded lymphocytes changed as follows; CD4(+) T lymphocytes increased, CD8(+) T lymphocytes decreased, and the proportion of CD3(-)CD16(+)56(+) NK cells was unchanged. The proportion of CD4(+)CD25(high+)Foxp3(+) regulatory T lymphocytes in CD4(+) T lymphocytes increased after ex vivo expansion in both groups, but to a greater degree in the recurrent group. This study showed that regulatory T lymphocytes, neither cytotoxic T lymphocytes nor NK cells, were extensively increased after ex vivo expansion, especially in recurrent ovarian carcinoma. These results may provide information that helps to guide the future development of adoptive immunotherapy against ovarian carcinoma.

[Application of numerical convolution in in vivo/in vitro correlation research].

PubMed

Yue, Peng

2009-01-01

This paper introduced the conception and principle of in vivo/in vitro correlation (IVIVC) and convolution/deconvolution methods, and elucidated in details the convolution strategy and method for calculating the in vivo absorption performance of the pharmaceutics according to the their pharmacokinetic data in Excel, then put the results forward to IVIVC research. Firstly, the pharmacokinetic data ware fitted by mathematical software to make up the lost points. Secondly, the parameters of the optimal fitted input function were defined by trail-and-error method according to the convolution principle in Excel under the hypothesis that all the input functions fit the Weibull functions. Finally, the IVIVC between in vivo input function and the in vitro dissolution was studied. In the examples, not only the application of this method was demonstrated in details but also its simplicity and effectiveness were proved by comparing with the compartment model method and deconvolution method. It showed to be a powerful tool for IVIVC research.

Biofouling resistance of boron-doped diamond neural stimulation electrodes is superior to titanium nitride electrodes in vivo.

PubMed

Meijs, S; Alcaide, M; Sørensen, C; McDonald, M; Sørensen, S; Rechendorff, K; Gerhardt, A; Nesladek, M; Rijkhoff, N J M; Pennisi, C P

2016-10-01

The goal of this study was to assess the electrochemical properties of boron-doped diamond (BDD) electrodes in relation to conventional titanium nitride (TiN) electrodes through in vitro and in vivo measurements. Electrochemical impedance spectroscopy, cyclic voltammetry and voltage transient (VT) measurements were performed in vitro after immersion in a 5% albumin solution and in vivo after subcutaneous implantation in rats for 6 weeks. In contrast to the TiN electrodes, the capacitance of the BDD electrodes was not significantly reduced in albumin solution. Furthermore, BDD electrodes displayed a decrease in the VTs and an increase in the pulsing capacitances immediately upon implantation, which remained stable throughout the whole implantation period, whereas the opposite was the case for the TiN electrodes. These results reveal that BDD electrodes possess a superior biofouling resistance, which provides significantly stable electrochemical properties both in protein solution as well as in vivo compared to TiN electrodes.

Analysis of tumor metabolism reveals mitochondrial glucose oxidation in genetically diverse, human glioblastomas in the mouse brain in vivo

PubMed Central

Marin-Valencia, Isaac; Yang, Chendong; Mashimo, Tomoyuki; Cho, Steve; Baek, Hyeonman; Yang, Xiao-Li; Rajagopalan, Kartik N.; Maddie, Melissa; Vemireddy, Vamsidhara; Zhao, Zhenze; Cai, Ling; Good, Levi; Tu, Benjamin P.; Hatanpaa, Kimmo J.; Mickey, Bruce E.; Matés, José M.; Pascual, Juan M.; Maher, Elizabeth A.; Malloy, Craig R.; DeBerardinis, Ralph J.; Bachoo, Robert M.

2012-01-01

SUMMARY Dysregulated metabolism is a hallmark of cancer cell lines, but little is known about the fate of glucose and other nutrients in tumors growing in their native microenvironment. To study tumor metabolism in vivo, we used an orthotopic mouse model of primary human glioblastoma (GBM). We infused 13C-labeled nutrients into mice bearing three independent GBM lines, each with a distinct set of mutations. All three lines displayed glycolysis, as expected for aggressive tumors. They also displayed unexpected metabolic complexity, oxidizing glucose via pyruvate dehydrogenase and the citric acid cycle, and using glucose to supply anaplerosis and other biosynthetic activities. Comparing the tumors to surrounding brain revealed obvious metabolic differences, notably the accumulation of a large glutamine pool within the tumors. Many of these same activities were conserved in cells cultured ex vivo from the tumors. Thus GBM cells utilize mitochondrial glucose oxidation during aggressive tumor growth in vivo. PMID:22682223

In vivo release of levonorgestrel from Sino-implant (II) — an innovative comparison of explant data.

PubMed

Callahan, Rebecca L; Taylor, Douglas; Jenkins, David W; Owen, Derek H; Cheng, Linan; Cancel, Aida M; Dorflinger, Laneta J; Steiner, Markus J

2015-10-01

Measuring the amount of progestin remaining in contraceptive implants used for different lengths of time provides useful information on in vivo release kinetics including change over time. We compared estimated in vivo levonorgestrel (LNG) release rates derived from Sino-implant (II) explants with similar data from removed Jadelle. We measured LNG remaining in 44 sets of Sino-implant (II) used for up to 7 years and removed in four Chinese clinics. Results were compared with published data for Jadelle explants used for up to 36 months. We estimated and compared monthly and daily LNG release rates for the two products using prediction models for drug release. We also estimated the dissolution profile similarity factor, f2, for LNG release. Both Sino-implant (II) and Jadelle release approximately 30% of total LNG load after 3 years. Results of fitting the data to a biologically plausible modified Higuchi prediction model indicate comparable release through 3 years. An estimated similarity factor of 80.6 (90% confidence interval: 70.8-85.7) indicates similarity in the dissolution profiles of the two implants. LNG release in vivo measured through explant analysis suggest that Sino-implant (II) and Jadelle may perform similarly through 3 years of use and could remain highly effective beyond this time point. These results align with published data for Jadelle and Sino-implant (II) showing high effectiveness for 5 years. Ongoing clinical studies comparing the products over 5 years present an opportunity to verify this supportive measure of clinical effectiveness. This innovative approach provides evidence that Sino-implant (II) may perform clinically similarly to Jadelle over 3 years and remain a highly effective contraceptive beyond this time point. Data from explant analyses show promise for investigating the equivalence of elusion profiles of contraceptive implants. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Comparative phytochemical analysis and antibacterial efficacy of in vitro and in vivo extracts from East Indian sandalwood tree (Santalum album L.).

PubMed

Misra, B B; Dey, S

2012-12-01

Sandalwood oil has been found in numerous therapeutic applications in traditional medicines such as Chinese traditional medicine and Ayurveda. However, there are no comparative accounts available in the literature that focused on in vitro and in vivo tree sample-derived extracts. Combined dichloromethane and methanol extracts were obtained from in vitro samples, that is, callus, somatic embryo and seedlings, and in vivo from leaves of non-oil-yielding young and oil-yielding matured trees. Phytochemical evaluation of the extracts reveals that the tree is rich in terpenoids, saponin, phenolics and tannins. The antibacterial properties of the five extracts were compared with sandalwood oil by screening against nine Gram-negative and five Gram-positive bacterial strains by disc diffusion, agar spot and TLC bioautography methods. Minimum inhibitory concentration (MIC) for sandalwood oil was determined to be in the range of 0·078-5 μg ml(-1) for most of the test micro-organisms screened. Bioautography results indicated the presence of potential antimicrobial constituents in somatic embryo extracts and sandalwood oil. Among the extracts screened, the somatic embryo extracts showed the strongest antibacterial activity comparable only with sandalwood oil and matured tree leaves' extract. The findings presented here also suggest that apart from sandalwood oil, other parts of this tree across developmental stages are also enriched with antibacterial principles. This study constitutes the first systematic investigation on phytochemical composition and antimicrobial efficacy of sandalwood tree across in vitro and in vivo developmental stages screened against thirteen bacterial strains by four methods. Using a battery of antimicrobial assay techniques, it is possible to follow the differential bioactive metabolic richness of plant parts, to decipher, for example comparable efficacy of somatic embryo extracts and sandalwood oil. © 2012 The Society for Applied Microbiology.

Nitric oxide production contributes to Bacillus anthracis edema toxin-associated arterial hypotension and lethality: ex vivo and in vivo studies in the rat

PubMed Central

Li, Yan; Cui, Xizhong; Xu, Wanying; Ohanjanian, Lernik; Sampath-Kumar, Hanish; Suffredini, Dante; Moayeri, Mahtab; Leppla, Stephen; Fitz, Yvonne

2016-01-01

We showed previously that Bacillus anthracis edema toxin (ET), comprised of protective antigen (PA) and edema factor (EF), inhibits phenylephrine (PE)-induced contraction in rat aortic rings and these effects are diminished in endothelial-denuded rings. Therefore, employing rat aortic ring and in vivo models, we tested the hypothesis that nitric oxide (NO) contributes to ET's arterial effects. Compared with rings challenged with PA alone, ET (PA + EF) reduced PE-stimulated maximal contractile force (MCF) and increased the PE concentration producing 50% MCF (EC50) (P < 0.0001). Compared with placebo, l-nitro-arginine methyl-ester (l-NAME), an NO synthase (NOS) inhibitor, reduced ET's effects on MCF and EC50 in patterns that approached or were significant (P = 0.06 and 0.03, respectively). In animals challenged with 24-h ET infusions, l-NAME (0.5 or 1.0 mg·kg−1·h−1) coadministration increased survival to 17 of 28 animals (60.7%) compared with 4 of 27 (14.8%) given placebo (P = 0.01). Animals receiving l-NAME but no ET all survived. Compared with PBS challenge, ET increased NO levels at 24 h and l-NAME decreased these increases (P < 0.0001). ET infusion decreased mean arterial blood pressure (MAP) in placebo and l-NAME-treated animals (P < 0.0001) but l-NAME reduced decreases in MAP with ET from 9 to 24 h (P = 0.03 for the time interaction). S-methyl-l-thiocitrulline, a selective neuronal NOS inhibitor, had effects in rings and, at a high dose in vivo models, comparable to l-NAME, whereas N′-[3-(aminomethyl)benzyl]-acetimidamide, a selective inducible NOS inhibitor, did not. NO production contributes to ET's arterial relaxant, hypotensive, and lethal effects in the rat. PMID:27448553

In–Depth Characterization of Viral Isolates from Plasma and Cells Compared with Plasma Circulating Quasispecies in Early HIV-1 Infection

PubMed Central

Erkizia, Itziar; Pino, Maria; Pou, Christian; Paredes, Roger; Clotet, Bonaventura; Martinez-Picado, Javier; Prado, Julia G.

2012-01-01

Background The use of in vitro models to unravel the phenotypic characteristics of circulating viral variants is key to understanding HIV-1 pathogenesis but limited by the availability of primary viral isolates from biological samples. However, overall in vivo genetic variability of HIV-1 within a subject may not be reflected in the viable viral population obtained after isolation. Although several studies have tried to determine whether viral populations expanded in vitro are representative of in vivo findings, the answer remains unclear due to the reduced number of clonal sequences analyzed or samples compared. In order to overcome previous experimental limitations, here we applied Deep Pyrosequencing (DPS) technology in combination with phenotypic experiments to analyze and compare with unprecedented detail the composition of viral isolates and in vivo quasispecies. Methodology/Principal Findings We amplified by DPS HIV-1 genomic regions covering gag, protease, integrase and env-V3 to characterize paired isolates from plasma and peripheral blood mononuclear cells and compare them with total plasma viral RNA in four recently HIV-1 infected subjects. Our study demonstrated the presence of unique haplotypes scattered between sample types with conservation of major variants. In addition, no differences in intra- and inter-population encoded protein variability were found between the different types of isolates or when these were compared to plasma viral RNA within subjects. Additionally, in vitro experiments demonstrated phenotypic similarities in terms of replicative capacity and co-receptor usage between viral isolates and plasma viral RNA. Conclusion This study is the first in-depth comparison and characterization of viral isolates from different sources and plasma circulating quasispecies using DPS in recently HIV-1 infected subjects. Our data supports the use of primary isolates regardless of their plasma or cellular origin to define genetic variability and biological traits of circulating HIV-1 quasispecies. PMID:22393441

Ex vivo fluorescence confocal microscopy for fast evaluation of tumour margins during Mohs surgery.

PubMed

Bennàssar, A; Vilata, A; Puig, S; Malvehy, J

2014-02-01

Ex vivo fluorescence confocal microscopy (FCM) enables real-time imaging of skin morphology directly in freshly excised tissue. FCM displays wide field-of-view mosaics with cellular resolution, thus enabling a rapid bedside pathology. An application of interest is rapid detection of residual basal cell carcinoma (BCC) in skin excisions during Mohs surgery. We sought to evaluate the sensitivity and specificity of ex vivo imaging with FCM for the detection of residual BCC in Mohs tissue excisions, and to calculate the time invested up to the diagnosis for both FCM and frozen sections. Eighty consecutive BCCs were prospectively collected and the margins scanned with ex vivo FCM, including excisions with and without residual BCC of all major subtypes. Each mosaic was divided into two or four, resulting in 480 submosaics for study. Every confocal submosaic was assessed for the presence or absence of BCC and compared with standard frozen sections as the gold standard. Furthermore, the time spent for each technique was calculated and compared. The overall sensitivity and specificity of detecting residual BCC were 88% and 99%, respectively. Moreover, the new technique reduced by almost two-thirds the time invested when compared with the processing of a frozen section (P < 0·001). The results demonstrate the feasibility of confocal mosaicing microscopy in fresh tissue for rapid surgical pathology, potentially to expedite and guide Mohs surgery with high accuracy. This observation is an important step towards the goal of using real-time surgical pathology for skin tumours. © 2013 British Association of Dermatologists.

Removing Distortion of Periapical Radiographs in Dental Digital Radiography Using Embedded Markers in an External frame.

PubMed

Kafieh, Rahele; Shahamoradi, Mahdi; Hekmatian, Ehsan; Foroohandeh, Mehrdad; Emamidoost, Mostafa

2012-10-01

To carry out in vivo and in vitro comparative pilot study to evaluate the preciseness of a newly proposed digital dental radiography setup. This setup was based on markers placed on an external frame to eliminate the measurement errors due to incorrect geometry in relative positioning of cone, teeth and the sensor. Five patients with previous panoramic images were selected to undergo the proposed periapical digital imaging for in vivo phase. For in vitro phase, 40 extracted teeth were replanted in dry mandibular sockets and periapical digital images were prepared. The standard reference for real scales of the teeth were obtained through extracted teeth measurements for in vitro application and were calculated through panoramic imaging for in vivo phases. The proposed image processing thechnique was applied on periapical digital images to distinguish the incorrect geometry. The recognized error was inversely applied on the image and the modified images were compared to the correct values. The measurement findings after the distortion removal were compared to our gold standards (results of panoramic imaging or measurements from extracted teeth) and showed the accuracy of 96.45% through in vivo examinations and 96.0% through in vitro tests. The proposed distortion removal method is perfectly able to identify the possible inaccurate geometry during image acquisition and is capable of applying the inverse transform to the distorted radiograph to obtain the correctly modified image. This can be really helpful in applications like root canal therapy, implant surgical procedures and digital subtraction radiography, which are essentially dependent on precise measurements.

Removing Distortion of Periapical Radiographs in Dental Digital Radiography Using Embedded Markers in an External frame

PubMed Central

Kafieh, Rahele; Shahamoradi, Mahdi; Hekmatian, Ehsan; Foroohandeh, Mehrdad; Emamidoost, Mostafa

2012-01-01

To carry out in vivo and in vitro comparative pilot study to evaluate the preciseness of a newly proposed digital dental radiography setup. This setup was based on markers placed on an external frame to eliminate the measurement errors due to incorrect geometry in relative positioning of cone, teeth and the sensor. Five patients with previous panoramic images were selected to undergo the proposed periapical digital imaging for in vivo phase. For in vitro phase, 40 extracted teeth were replanted in dry mandibular sockets and periapical digital images were prepared. The standard reference for real scales of the teeth were obtained through extracted teeth measurements for in vitro application and were calculated through panoramic imaging for in vivo phases. The proposed image processing thechnique was applied on periapical digital images to distinguish the incorrect geometry. The recognized error was inversely applied on the image and the modified images were compared to the correct values. The measurement findings after the distortion removal were compared to our gold standards (results of panoramic imaging or measurements from extracted teeth) and showed the accuracy of 96.45% through in vivo examinations and 96.0% through in vitro tests. The proposed distortion removal method is perfectly able to identify the possible inaccurate geometry during image acquisition and is capable of applying the inverse transform to the distorted radiograph to obtain the correctly modified image. This can be really helpful in applications like root canal therapy, implant surgical procedures and digital subtraction radiography, which are essentially dependent on precise measurements. PMID:23724372

Bioavailability enhancement of curcumin by complexation with phosphatidyl choline.

PubMed

Gupta, Nishant Kumar; Dixit, Vinod Kumar

2011-05-01

Curcumin is a major constituent of rhizomes of Curcuma longa. Pharmacokinetic studies of curcumin reveal its poor absorption through intestine. Objective of the present study was to enhance bioavailability of curcumin by its complexation with phosphatidyl choline (PC). Complex of curcumin was prepared with PC and characterized on the basis of solubility, melting point, differential scanning calorimetry, thin layer chromatography, and infrared spectroscopic analysis. Everted intestine sac technique was used to study ex vivo drug absorption of curcumin-PC (CU-PC) complex and plain curcumin. Pharmacokinetic studies were performed in rats, and hepatoprotective activity of CU-PC complex was also compared with curcumin and CU-PC physical mixture in isolated rat hepatocytes. Analytical reports along with spectroscopic data revealed the formation of complex. The results of ex vivo study show that CU-PC complex has significantly increased absorption compared with curcumin, when given in equimolar doses. Complex showed enhanced bioavailability, improved pharmacokinetics, and increased hepatoprotective activity as compared with curcumin or CU-PC physical mixture. Enhanced bioavailability of CU-PC complex may be due to the amphiphilic nature of the complex, which greatly enhance the water and lipid solubility of the curcumin. The present study clearly indicates the superiority of complex over curcumin, in terms of better absorption, enhanced bioavailability, and improved pharmacokinetics. Copyright © 2010 Wiley-Liss, Inc.

Toward global standards for comparator pharmaceutical products: case studies of amoxicillin, metronidazole, and zidovudine in the Americas.

PubMed

Löbenberg, Raimar; Chacra, Nadia B; Stippler, Erika S; Shah, Vinod P; DeStefano, Anthony J; Hauck, Walter W; Williams, Roger L

2012-09-01

This study compared in vitro dissolution characteristics and other quality measures of different amoxicillin, metronidazole, and zidovudine products purchased in the Americas to a comparator pharmaceutical product (CPP). These three drugs are classified as Biopharmaceutics Classification System Class I drugs with the possibility that dissolution findings might be used to document bioequivalence. All investigated zidovudine products were found to be in vitro equivalent to the CPP. Only 3 of 12 tested amoxicillin products were found to be in vitro equivalent to the CPP. None of the tested metronidazole products were in vitro equivalent to the CPP. These findings suggest but do not confirm bioinequivalence where in vitro comparisons failed, given that an in vivo blood level study might have confirmed bioequivalence. At times, identifying a CPP in one of the selected markets proved difficult. The study demonstrates that products sold across national markets may not be bioequivalent. When coupled with the challenge of identifying a CPP in different countries, the results of this study suggest the value of an international CPP as well as increased use of BCS approaches as means of either documenting bioequivalence or signaling the need for further in vivo studies. Because of increased movement of medicines across national borders, practitioners and patients would benefit from these approaches.

Factorial design studies of antiretroviral drug-loaded stealth liposomal injectable: PEGylation, lyophilization and pharmacokinetic studies

NASA Astrophysics Data System (ADS)

Sudhakar, Beeravelli; Krishna, Mylangam Chaitanya; Murthy, Kolapalli Venkata Ramana

2016-01-01

The aim of the present study was to formulate and evaluate the ritonavir-loaded stealth liposomes by using 32 factorial design and intended to delivered by parenteral delivery. Liposomes were prepared by ethanol injection method using 32 factorial designs and characterized for various physicochemical parameters such as drug content, size, zeta potential, entrapment efficiency and in vitro drug release. The optimization process was carried out using desirability and overlay plots. The selected formulation was subjected to PEGylation using 10 % PEG-10000 solution. Stealth liposomes were characterized for the above-mentioned parameters along with surface morphology, Fourier transform infrared spectrophotometer, differential scanning calorimeter, stability and in vivo pharmacokinetic studies in rats. Stealth liposomes showed better result compared to conventional liposomes due to effect of PEG-10000. The in vivo studies revealed that stealth liposomes showed better residence time compared to conventional liposomes and pure drug solution. The conventional liposomes and pure drug showed dose-dependent pharmacokinetics, whereas stealth liposomes showed long circulation half-life compared to conventional liposomes and pure ritonavir solution. The results of statistical analysis showed significance difference as the p value is (<0.05) by one-way ANOVA. The result of the present study revealed that stealth liposomes are promising tool in antiretroviral therapy.

Long-term exposure to a butter-rich diet induces mild-to-moderate steatosis in Chang liver cells and Swiss albino mice models.

PubMed

Nalloor, Thomas John Philip; Kumar, Nitesh; Narayanan, Kasinathan; Palanimuthu, Vasanth Raj

2017-05-01

Butter is one of the widely used fats present in the diet. However, there is no satisfactory study available that evaluates the effect of a high-fat diet containing butter as the principal fat on the development of non-alcoholic fatty liver disease (NAFLD). In the present study, butter was used for the development of steatosis in Chang liver cells in an in vitro study and Swiss albino mice in an in vivo study. In vitro steatosis was established, and butter was compared with oleic acid in Chang liver cells using an oil red O (ORO)-based colorimetric assay. In the in vivo study, a butter-rich special diet was fed for 15 weeks to mice, who showed no significant change in body weight. The expression pattern of phosphatase and tensin homolog (PTEN) and miR-21 was compared by reverse transcriptase-PCR. Special diet-fed animals showed downregulated PTEN compared to normal diet-fed animals, while levels of miR-21 remained the same. Elevations in biochemical parameters, viz., triglycerides and liver function tests showed symptoms of onset of NAFLD. Histophathological study of livers of test animals confirmed mild-to-moderate degree of NAFLD.

The influence of droplet size on the stability, in vivo digestion, and oral bioavailability of vitamin E emulsions.

PubMed

Parthasarathi, S; Muthukumar, S P; Anandharamakrishnan, C

2016-05-18

Vitamin E (α-tocopherol) is a nutraceutical compound, which has been shown to possess potent antioxidant and anticancer activity. However, its biological activity may be limited by its poor bioavailability. Colloidal delivery systems have shown wide applications in the food and pharmaceutical industries to deliver lipophilic bioactive compounds. In this study, we have developed conventional and nanoemulsions of vitamin E from food grade ingredients (sunflower oil, saponin, and water) and showed the nanoemulsion formulation increased the oral bioavailability when compared to the conventional emulsion. The mean droplet diameters in the nano and conventional emulsions were 0.277 and 1.285 μm, respectively. The stability of the emulsion formulation after thermal processing, long-term storage at different temperatures, mechanical stress and in plasma was determined. The results showed that the saponin coated nanoemulsion was stable to droplet coalescence during thermal processing (30-90 °C), long-term storage and mechanical stress when compared to the conventional emulsion. The biological fate of the emulsion formulations were studied using male Wistar rats as an animal model. The emulsion droplet stability during passage through the gastrointestinal tract was evaluated by their introduction into rat stomachs. Microscopy was used to investigate the structural changes that occurred during digestion. Both the conventional emulsion and nanoemulsion formulations showed strong evidence of droplet flocculation and coalescence during in vivo digestion. The in vivo oral bioavailability study revealed that vitamin E in a nanoemulsion form showed a 3-fold increase in the AUC when compared to the conventional emulsion. The information reported in this study will facilitate the design of colloidal delivery systems using nanoemulsion formulations.

Ex vivo blood vessel bioreactor for analysis of the biodegradation of magnesium stent models with and without vessel wall integration.

PubMed

Wang, Juan; Liu, Lumei; Wu, Yifan; Maitz, Manfred F; Wang, Zhihong; Koo, Youngmi; Zhao, Ansha; Sankar, Jagannathan; Kong, Deling; Huang, Nan; Yun, Yeoheung

2017-03-01

Current in vitro models fail in predicting the degradation rate and mode of magnesium (Mg) stents in vivo. To overcome this, the microenvironment of the stent is simulated here in an ex vivo bioreactor with porcine aorta and circulating medium, and compared with standard static in vitro immersion and with in vivo rat aorta models. In ex vivo and in vivo conditions, pure Mg wires were exposed to the aortic lumen and inserted into the aortic wall to mimic early- and long-term implantation, respectively. Results showed that: 1) Degradation rates of Mg were similar for all the fluid diffusion conditions (in vitro static, aortic wall ex vivo and in vivo); however, Mg degradation under flow condition (i.e. in the lumen) in vivo was slower than ex vivo; 2) The corrosion mode in the samples can be mainly described as localized (in vitro), mixed localized and uniform (ex vivo), and uniform (in vivo); 3) Abundant degradation products (MgO/Mg(OH) 2 and Ca/P) with gas bubbles accumulated around the localized degradation regions ex vivo, but a uniform and thin degradation product layer was found in vivo. It is concluded that the ex vivo vascular bioreactor provides an improved test setting for magnesium degradation between static immersion and animal experiments and highlights its promising role in bridging degradation behavior and biological response for vascular stent research. Magnesium and its alloys are candidates for a new generation of biodegradable stent materials. However, the in vitro degradation of magnesium stents does not match the clinical degradation rates, corrupting the validity of conventional degradation tests. Here we report an ex vivo vascular bioreactor, which allows simulation of the microenvironment with and without blood vessel integration to study the biodegradation of magnesium implants in comparison with standard in vitro test conditions and with in vivo implantations. The bioreactor did simulate the corrosion of an intramural implant very well, but showed too high degradation for non-covered implants. It is concluded that this system is in between static incubation and animal experiments concerning the predictivity of the degradation. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Studying the Immunomodulatory Effects of Small Molecule Ras Inhibitors in Animal Models of Rheumatoid Arthritis

DTIC Science & Technology

2017-10-01

methotrexate (MTX) provides a superior protective effect compared to monotherapy. (iii) In the AIA model the FTS derivative, F-FTS, showed higher...therapeutic efficacy compared to FTS. (iv) The functional genomics studies showed that FTS therapy inhibits the in vivo TH17 immune response. (v) FTS semi... Description shall include pertinent data and graphs in sufficient detail to explain any significant results achieved. A succinct description of the

In vivo and in vitro assessment of an intraoral dental colorimeter.

PubMed

Karaagaclioglu, Lale; Terzioglu, Hakan; Yilmaz, Burak; Yurdukoru, Bengul

2010-06-01

The purpose of this study was to assess the performance of an intraoral dental colorimeter. In vivo repeatability of an intraoral colorimeter was assessed by performing color measurements of 30 individuals' right maxillary central incisor. Three consecutive measurements from each individual were made. In the in vitro part of the study, 25 metal-ceramic and 25 all-ceramic specimens were prepared. Five shades of metal-ceramic and all-ceramic specimens were selected for color determination. A widely recognized in vitro colorimeter was used as the control group for the in vitro performance assessment of the in vivo colorimeter. The color differentiation capability of two colorimeters was compared with the readings obtained from ceramic specimens. DeltaE values between shade groups of ceramic specimens were calculated and statistically analyzed with Student's t-test. The repeatability of the intraoral instrument was evaluated statistically with Intraclass correlation coefficient. The in vivo evaluation results showed that the overall repeatability coefficient values of L*, a*, and b* notations of the intraoral colorimeter were "excellent." The color differences (DeltaE) calculated between the colorimeters were significant only between shades A(1)-B(1) for metal-ceramic specimens (p= 0.002); however, from 5 of 10 shade couples of all-ceramic specimens, the color differences obtained from the readings of the in vivo colorimeter were significantly different from that of the in vitro colorimeter (p < 0.001). For all specimens, the differences between DeltaE values were within clinically acceptable limits (<3.5). Within the limitations of this study, the intraoral colorimeter exhibited successful in vivo repeatability; however, the color difference detection performance of the device varied depending on the translucency of the specimens.

The impact of microfluidic mixing of triblock micelleplexes on in vitro / in vivo gene silencing and intracellular trafficking

NASA Astrophysics Data System (ADS)

Feldmann, Daniel P.; Xie, Yuran; Jones, Steven K.; Yu, Dongyue; Moszczynska, Anna; Merkel, Olivia M.

2017-06-01

The triblock copolymer polyethylenimine-polycaprolactone-polyethylene glycol (PEI-PCL-PEG) has been shown to spontaneously assemble into nano-sized particulate carriers capable of complexing with nucleic acids for gene delivery. The objective of this study was to investigate micelleplex characteristics, their in vitro and in vivo fate following microfluidic preparation of siRNA nanoparticles compared to the routinely used batch reactor mixing technique. Herein, PEI-PCL-PEG nanoparticles were prepared with batch reactor or microfluidic mixing techniques and characterized by various biochemical assays and in cell culture. Microfluidic nanoparticles showed a reduction of overall particle size as well as a more uniform size distribution when compared to batch reactor pipette mixing. Confocal microscopy, flow cytometry and qRT-PCR displayed the subcellular delivery of the microfluidic formulation and confirmed the ability to achieve mRNA knockdown. Intratracheal instillation of microfluidic formulation resulted in a significantly more efficient (p < 0.05) knockdown of GAPDH compared to treatment with the batch reactor formulation. The use of microfluidic mixing techniques yields an overall smaller and more uniform PEG-PCL-PEI nanoparticle that is able to more efficiently deliver siRNA in vivo. This preparation method may prove to be useful when a scaled up production of well-defined polyplexes is required.

"Deep-media culture condition" promoted lumen formation of endothelial cells within engineered three-dimensional tissues in vitro.

PubMed

Sekiya, Sachiko; Shimizu, Tatsuya; Yamato, Masayuki; Okano, Teruo

2011-03-01

In the field of tissue engineering, the induction of microvessels into tissues is an important task because of the need to overcome diffusion limitations of oxygen and nutrients within tissues. Powerful methods to create vessels in engineered tissues are needed for creating real living tissues. In this study, we utilized three-dimensional (3D) highly cell dense tissues fabricated by cell sheet technology. The 3D tissue constructs are close to living-cell dense tissue in vivo. Additionally, creating an endothelial cell (EC) network within tissues promoted neovascularization promptly within the tissue after transplantation in vivo. Compared to the conditions in vivo, however, common in vitro cell culture conditions provide a poor environment for creating lumens within 3D tissue constructs. Therefore, for determining adequate conditions for vascularizing engineered tissue in vitro, our 3D tissue constructs were cultured under a "deep-media culture conditions." Compared to the control conditions, the morphology of ECs showed a visibly strained cytoskeleton, and the density of lumen formation within tissues increased under hydrostatic pressure conditions. Moreover, the increasing expression of vascular endothelial cadherin in the lumens suggested that the vessels were stabilized in the stimulated tissues compared with the control. These findings suggested that deep-media culture conditions improved lumen formation in engineered tissues in vitro.

Evaluating Dual Activity LPA Receptor Pan-Antagonist/Autotaxin Inhibitors as Anti-Cancer Agents in vivo using Engineered Human Tumors

PubMed Central

Xu, Xiaoyu; Yang, Guanghui; Zhang, Honglu; Prestwich, Glenn D.

2009-01-01

Using an in situ crosslinkable hydrogel that mimics the extracellular matrix (ECM), cancer cells were encapsulated and injected in vivo following a “tumor engineering” strategy for orthotopic xenografts. Specifically, we created several three-dimensional (3-D) human tumor xenografts and evaluated the tumor response to BrP-LPA, a novel dual function LPA antagonist/ATX inhibitor (LPAa/ATXi). First, we describe the model system and the optimization of semi-synthetic ECM (sECM) compositions and injection parameters for engineered xenografts. Second, we summarize a study to compare angiogenesis inhibition in vivo, comparing BrP-LPA to the kinase inhibitor sunitinib maleate (Sutent). Third, we compare treatment of engineered breast tumors with LPAa/ATXi alone with treatment with Taxol. Fourth, using a re-optimized sECM for non-small cell lung cancer cells, we created reproducibly sized subcutaneous lung tumors and evaluated their response to treatment with LPAa/ATXi. Fifth, we summarize the data on the use of LPAa/ATXi to treat a model for colon cancer metastasis to the liver. Taken together, these improved, more realistic xenografts show considerable utility for evaluating the potential of novel anti-metastatic, anti-proliferative, and anti-angiogenic compounds that modify signal transduction through the LPA signaling pathway. PMID:19682598

In vitro antioxidant profiling of seabuckthorn varieties and their adaptogenic response to high altitude-induced stress

NASA Astrophysics Data System (ADS)

Sharma, Priyanka; Suryakumar, Geetha; Singh, Virendra; Misra, Kshipra; Singh, Shashi Bala

2015-08-01

In the past few years, seabuckthorn plants have gained special attention due to their ability to grow in the harshest of the environment. This adaptability may be contributed by various antioxidants present in the plants besides other morphological adaptation. As in vivo studies cannot be justified without in vitro studies, the present investigation carried out evaluation of both in vitro and in vivo antioxidant potentials of aqueous and alcoholic extracts of the leaves of Hippophae salicifolia (HS) and Hippophae rhamnoides mongolica (HRM) in comparison with Hippophae rhamnoides turkestanica (HRT). The results had clearly depicted that in vitro antioxidant potential of the extracts was responsible for the in vivo adaptogenic performance in animals during cold and hypoxia exposure under restraint stress. Total phenolic content (TPC), total flavonoid content (TFC), total protein content, and antioxidant potential were determined. For adaptogenic studies, rats with oral drug supplementation were exposed to Cold-hypoxia-restraint (C-H-R) stresses-induced hypothermia, as a measure of endurance. Aqueous extracts of HS showed maximum (99 %) resistance compared to HRT (81 %) and HRM (29 %). The levels of biochemical parameters such as malondialdehyde (MDA), reactive oxygen species (ROS), lactate dehydrogenase (LDH), superoxide dismutase (SOD), glutathione (GSH/GSSG), and catalase (CAT) in blood samples also revealed that the aqueous leaf extract of HS has better antioxidant and adaptogenic potential compared to HRM.

Preliminary study of synthetic aperture tissue harmonic imaging on in-vivo data

NASA Astrophysics Data System (ADS)

Rasmussen, Joachim H.; Hemmsen, Martin C.; Madsen, Signe S.; Hansen, Peter M.; Nielsen, Michael B.; Jensen, Jørgen A.

2013-03-01

A method for synthetic aperture tissue harmonic imaging is investigated. It combines synthetic aperture sequen- tial beamforming (SASB) with tissue harmonic imaging (THI) to produce an increased and more uniform spatial resolution and improved side lobe reduction compared to conventional B-mode imaging. Synthetic aperture sequential beamforming tissue harmonic imaging (SASB-THI) was implemented on a commercially available BK 2202 Pro Focus UltraView ultrasound system and compared to dynamic receive focused tissue harmonic imag- ing (DRF-THI) in clinical scans. The scan sequence that was implemented on the UltraView system acquires both SASB-THI and DRF-THI simultaneously. Twenty-four simultaneously acquired video sequences of in-vivo abdominal SASB-THI and DRF-THI scans on 3 volunteers of 4 different sections of liver and kidney tissues were created. Videos of the in-vivo scans were presented in double blinded studies to two radiologists for image quality performance scoring. Limitations to the systems transmit stage prevented user defined transmit apodization to be applied. Field II simulations showed that side lobes in SASB could be improved by using Hanning transmit apodization. Results from the image quality study show, that in the current configuration on the UltraView system, where no transmit apodization was applied, SASB-THI and DRF-THI produced equally good images. It is expected that given the use of transmit apodization, SASB-THI could be further improved.

Indocyanine Green Enables Near-Infrared Fluorescence Imaging of Lipid-Rich, Inflamed Atherosclerotic Plaques

PubMed Central

Vinegoni, Claudio; Botnaru, Ion; Aikawa, Elena; Calfon, Marcella A.; Iwamoto, Yoshiko; Folco, Eduardo J.; Ntziachristos, Vasilis; Weissleder, Ralph; Libby, Peter; Jaffer, Farouc A.

2011-01-01

New high-resolution molecular and structural imaging strategies are needed to visualize high-risk plaques that are likely to cause acute myocardial infarction, because current diagnostic methods do not reliably identify at-risk subjects. While molecular imaging agents are available for lower-resolution detection of atherosclerosis in large arteries, a lack of imaging agents coupled to high-resolution modalities has limited molecular imaging of atherosclerosis in the smaller coronary arteries [AU: ok? YES]. Here, we have demonstrated that indocyanine green (ICG), an FDA-approved near-infrared fluorescence (NIRF) emitting compound, targets atheromas within 20 minutes of injection and provides sufficient signal enhancement for in vivo detection of lipid-rich, inflamed, coronary-sized plaques in atherosclerotic rabbits. In vivo NIRF sensing was achieved with an intravascular wire in the aortae, a vessel of comparable caliber to human coronary arteries. Ex vivo fluorescence reflectance imaging studies showed high plaque target-to-background ratios in atheroma-bearing rabbits injected with ICG, compared to atheroma-bearing rabbits injected with saline. In vitro studies using human macrophages established that ICG preferentially targets lipid-loaded macrophages. In an early clinical study of human atheroma specimens from four patients, we found that ICG colocalized with plaque macrophages and lipids. The atheroma-targeting capability of ICG has the potential to accelerate the clinical development of NIRF molecular imaging of high-risk plaques in humans. PMID:21613624

Large Animal Models for Foamy Virus Vector Gene Therapy

PubMed Central

Trobridge, Grant D.; Horn, Peter A.; Beard, Brian C.; Kiem, Hans-Peter

2012-01-01

Foamy virus (FV) vectors have shown great promise for hematopoietic stem cell (HSC) gene therapy. Their ability to efficiently deliver transgenes to multi-lineage long-term repopulating cells in large animal models suggests they will be effective for several human hematopoietic diseases. Here, we review FV vector studies in large animal models, including the use of FV vectors with the mutant O6-methylguanine-DNA methyltransferase, MGMTP140K to increase the number of genetically modified cells after transplantation. In these studies, FV vectors have mediated efficient gene transfer to polyclonal repopulating cells using short ex vivo transduction protocols designed to minimize the negative effects of ex vivo culture on stem cell engraftment. In this regard, FV vectors appear superior to gammaretroviral vectors, which require longer ex vivo culture to effect efficient transduction. FV vectors have also compared favorably with lentiviral vectors when directly compared in the dog model. FV vectors have corrected leukocyte adhesion deficiency and pyruvate kinase deficiency in the dog large animal model. FV vectors also appear safer than gammaretroviral vectors based on a reduced frequency of integrants near promoters and also near proto-oncogenes in canine repopulating cells. Together, these studies suggest that FV vectors should be highly effective for several human hematopoietic diseases, including those that will require relatively high percentages of gene-modified cells to achieve clinical benefit. PMID:23223198

Early Detection of Myocardial Bioenergetic Deficits: A 9.4 Tesla Complete Non Invasive 31P MR Spectroscopy Study in Mice with Muscular Dystrophy.

PubMed

Cui, Weina; Jang, Albert; Zhang, Pengyuan; Thompson, Brian; Townsend, DeWayne; Metzger, Joseph M; Zhang, Jianyi

2015-01-01

Duchenne muscular dystrophy (DMD) is the most common fatal form of muscular dystrophy characterized by striated muscle wasting and dysfunction. Patients with DMD have a very high incidence of heart failure, which is increasingly the cause of death in DMD patients. We hypothesize that in the in vivo system, the dystrophic cardiac muscle displays bioenergetic deficits prior to any functional or structural deficits. To address this we developed a complete non invasive 31P magnetic resonance spectroscopy (31P MRS) approach to measure myocardial bioenergetics in the heart in vivo. Six control and nine mdx mice at 5 months of age were used for the study. A standard 3D -Image Selected In vivo Spectroscopy (3D-ISIS) sequence was used to provide complete gradient controlled three-dimensional localization for heart 31P MRS. These studies demonstrated dystrophic hearts have a significant reduction in PCr/ATP ratio compare to normal (1.59±0.13 vs 2.37±0.25, p<0.05). Our present study provides the direct evidence of significant cardiac bioenergetic deficits in the in vivo dystrophic mouse. These data suggest that energetic defects precede the development of significant hemodynamic or structural changes. The methods provide a clinically relevant approach to use myocardial energetics as an early marker of disease in the dystrophic heart. The new method in detecting the in vivo bioenergetics abnormality as an early non-invasive marker of emerging dystrophic cardiomyopathy is critical in management of patients with DMD, and optimized therapies aimed at slowing or reversing the cardiomyopathy.

Limitations of predicting in vivo biostability of multiphase polyurethane elastomers using temperature-accelerated degradation testing.

PubMed

Padsalgikar, Ajay; Cosgriff-Hernandez, Elizabeth; Gallagher, Genevieve; Touchet, Tyler; Iacob, Ciprian; Mellin, Lisa; Norlin-Weissenrieder, Anna; Runt, James

2015-01-01

Polyurethane biostability has been the subject of intense research since the failure of polyether polyurethane pacemaker leads in the 1980s. Accelerated in vitro testing has been used to isolate degradation mechanisms and predict clinical performance of biomaterials. However, validation that in vitro methods reproduce in vivo degradation is critical to the selection of appropriate tests. High temperature has been proposed as a method to accelerate degradation. However, correlation of such data to in vivo performance is poor for polyurethanes due to the impact of temperature on microstructure. In this study, we characterize the lack of correlation between hydrolytic degradation predicted using a high temperature aging model of a polydimethylsiloxane-based polyurethane and its in vivo performance. Most notably, the predicted molecular weight and tensile property changes from the accelerated aging study did not correlate with clinical explants subjected to human biological stresses in real time through 5 years. Further, DMTA, ATR-FTIR, and SAXS experiments on samples aged for 2 weeks in PBS indicated greater phase separation in samples aged at 85°C compared to those aged at 37°C and unaged controls. These results confirm that microstructural changes occur at high temperatures that do not occur at in vivo temperatures. In addition, water absorption studies demonstrated that water saturation levels increased significantly with temperature. This study highlights that the multiphase morphology of polyurethane precludes the use of temperature accelerated biodegradation for the prediction of clinical performance and provides critical information in designing appropriate in vitro tests for this class of materials. © 2014 Wiley Periodicals, Inc.

Raman Spectroscopy of Experimental Oral Carcinogenesis: Study on Sequential Cancer Progression in Hamster Buccal Pouch Model.

PubMed

Kumar, Piyush; Bhattacharjee, Tanmoy; Ingle, Arvind; Maru, Girish; Krishna, C Murali

2016-10-01

Oral cancers suffer from poor 5-year survival rates, owing to late detection of the disease. Current diagnostic/screening tools need to be upgraded in view of disadvantages like invasiveness, tedious sample preparation, long output times, and interobserver variances. Raman spectroscopy has been shown to identify many disease conditions, including oral cancers, from healthy conditions. Further studies in exploring sequential changes in oral carcinogenesis are warranted. In this Raman spectroscopy study, sequential progression in experimental oral carcinogenesis in Hamster buccal pouch model was investigated using 3 approaches-ex vivo, in vivo sequential, and in vivo follow-up. In all these studies, spectral changes show lipid dominance in early stages while later stages and tumors showed increased protein to lipid ratio and nucleic acids. On similar lines, early weeks of 7,12-dimethylbenz(a)anthracene-treated and control groups showed higher overlap and low classification. The classification efficiency increased progressively, reached a plateau phase and subsequently increased up to 100% by 14 weeks. The misclassifications between treated and control spectra suggested some changes in controls as well, which was confirmed by a careful reexamination of histopathological slides. These findings suggests Raman spectroscopy may be able to identify microheterogeneity, which may often go unnoticed in conventional biochemistry wherein tissue extracts are employed, as well as in histopathology. In vivo findings, quite comparable to gold-standard supported ex vivo findings, give further proof of Raman spectroscopy being a promising label-free, noninvasive diagnostic adjunct for future clinical applications. © The Author(s) 2015.

Comparative analysis of Fe ion-induced mutations in murine tissue and cells

NASA Astrophysics Data System (ADS)

Kronenberg, A.; Gauny, S.; Kwoh, E.; Dan, C.; Connolly, L.; Turker, M.

Space flight exposes astronauts to densely ionizing heavy ions including Fe ions This study is designed to assess the impact of the tissue microenvironment on the cytotoxic and mutagenic effects of 1 GeV amu Fe ions in kidney epithelial cells from one mouse strain irradiated either in vitro or in vivo Three to five month old Aprt heterozygous mice are used from a C57BL6 DBA2 cross B6D2F1 or kidney cells are used that were established from these mice Cells and animals were exposed in the plateau portion of the Bragg peak 159 keV mu m at the NASA Space Radiation Laboratories NSRL at Brookhaven National Laboratory Approximately equal numbers of male and female animals were used for the in vivo studies In vitro experiments demonstrated exponential cell killing with a D 0 of 92 cGy Three Aprt mutation experiments have been performed in kidney cells exposed to graded doses of Fe ions in vitro 0-2 Gy Studies to date indicate that Fe ions are mutagenic to kidney epithelial cells irradiated in vitro with a linear induction of mutants as a function of dose In vivo experiments have been completed on two thirds of the animals planned for the study Kidney cells were retrieved from the animals at two time points 2-3 months post-irradiation or 8-9 months post-irradiation Fe ion exposure in vivo led to exponential killing of kidney epithelial cells that was still evident 8-9 months post-exposure In vivo irradiation also results

Enhanced dermal delivery of diflucortolone valerate using lecithin/chitosan nanoparticles: in-vitro and in-vivo evaluations.

PubMed

Özcan, Ipek; Azizoğlu, Erkan; Senyiğit, Taner; Özyazıcı, Mine; Özer, Özgen

2013-01-01

The objective of this study was to prepare a suitable formulation for dermal delivery of diflucortolone valerate (DFV) that would maintain the localization in skin layers without any penetration and to optimize efficiency of DFV. Drug-loaded lecithin/chitosan nanoparticles with high entrapment efficiency (86.8%), were successfully prepared by ionic interaction technique. Sustained release of DFV was achieved without any initial burst release. Nanoparticles were also incorporated into chitosan gel at different ratios for preparing a more suitable formulation for topical drug delivery with adequate viscosity. In ex-vivo permeation studies, nanoparticles increased the accumulation of DFV especially in the stratum corneum + epidermis of rat skin without any significant permeation. Retention of DFV from nanoparticle in chitosan gel formulation (0.01%) was twofold higher than commercial cream, although it contained ten times less DFV. Nanoparticles in gel formulations produced significantly higher edema inhibition in rats compared with commercial cream in in-vivo studies. Skin blanching assay using a chromameter showed vasoconstriction similar to that of the commercial product. There were no barrier function changes upon application of nanoparticles. In-vitro and in-vivo results demonstrated that lecithin/chitosan nanoparticles in chitosan gel may be a promising carrier for dermal delivery of DFV in various skin disorders.

Enhanced dermal delivery of diflucortolone valerate using lecithin/chitosan nanoparticles: in-vitro and in-vivo evaluations

PubMed Central

Özcan, İpek; Azizoğlu, Erkan; Şenyiğit, Taner; Özyazıcı, Mine; Özer, Özgen

2013-01-01

The objective of this study was to prepare a suitable formulation for dermal delivery of diflucortolone valerate (DFV) that would maintain the localization in skin layers without any penetration and to optimize efficiency of DFV. Drug-loaded lecithin/chitosan nanoparticles with high entrapment efficiency (86.8%), were successfully prepared by ionic interaction technique. Sustained release of DFV was achieved without any initial burst release. Nanoparticles were also incorporated into chitosan gel at different ratios for preparing a more suitable formulation for topical drug delivery with adequate viscosity. In ex-vivo permeation studies, nanoparticles increased the accumulation of DFV especially in the stratum corneum + epidermis of rat skin without any significant permeation. Retention of DFV from nanoparticle in chitosan gel formulation (0.01%) was twofold higher than commercial cream, although it contained ten times less DFV. Nanoparticles in gel formulations produced significantly higher edema inhibition in rats compared with commercial cream in in-vivo studies. Skin blanching assay using a chromameter showed vasoconstriction similar to that of the commercial product. There were no barrier function changes upon application of nanoparticles. In-vitro and in-vivo results demonstrated that lecithin/chitosan nanoparticles in chitosan gel may be a promising carrier for dermal delivery of DFV in various skin disorders. PMID:23390364

Annexin V conjugated nanobubbles: A novel ultrasound contrast agent for in vivo assessment of the apoptotic response in cancer therapy.

PubMed

Zhou, Tian; Cai, Wenbin; Yang, Hengli; Zhang, Huizhong; Hao, Minghua; Yuan, Lijun; Liu, Jie; Zhang, Li; Yang, Yilin; Liu, Xi; Deng, Jianling; Zhao, Ping; Yang, Guodong; Duan, Yunyou

2018-04-28

In vivo assessment of apoptotic response to cancer therapy is believed to be very important for optimizing management of treatment. However, few noninvasive strategies are currently available to monitor the therapeutic response in vivo. Ultrasonography has been used to detect apoptotic cell death in vivo, but a high-frequency transducer is needed. Fortunately, the capability of ultrasound contrast agents (UCAs) to exit the leaky vasculature of tumors enables ultrasound-targeted imaging of molecular events in response to cancer therapy. In this study, we prepared a novel nano-sized UCA, namely, Annexin V-conjugated nanobubbles (AV-NBs, 635.5 ± 25.4 nm). In vitro studies revealed that AV-NBs were relatively stable and highly echogenic. Moreover, these AV-NBs could easily extravasate into the tumor vasculature and recognize the apoptotic cells with high specificity and affinity in tumors sensitive to chemotherapy. Ultrasound imaging results demonstrated that AV-NBs had higher echogenicity and significantly greater enhancement compared with the untargeted control NBs (P < 0.01) inside the tumors after chemotherapy. Taken together, this study provides a promising method to accurately evaluate therapeutic effects at the molecular level to support cancer management. Copyright © 2018 Elsevier B.V. All rights reserved.

An in vivo study of the effect of a 38 percent hydrogen peroxide in-office whitening agent on enamel.

PubMed

Cadenaro, Milena; Navarra, Chiara Ottavia; Mazzoni, Annalisa; Nucci, Cesare; Matis, Bruce A; Di Lenarda, Roberto; Breschi, Lorenzo

2010-04-01

In an in vivo study, the authors tested the hypothesis that no difference in enamel surface roughness is detectable either during or after bleaching with a high-concentration in-office whitening agent. The authors performed profilometric and scanning electron microscopic (SEM) analyses of epoxy resin replicas of the upper right incisors of 20 participants at baseline (control) and after each bleaching treatment with a 38 percent hydrogen peroxide whitening agent, applied four times, at one-week intervals. The authors used analysis of variance for repeated measures to analyze the data statistically. The profilometric analysis of the enamel surface replicas after the in vivo bleaching protocol showed no significant difference in surface roughness parameters (P > .05) compared with those at baseline, irrespective of the time interval. Results of the correlated SEM analysis showed no relevant alteration on the enamel surface. Results of this in vivo study support the tested hypothesis that the application of a 38 percent hydrogen peroxide in-office whitening agent does not alter enamel surface roughness, even after multiple applications. The use of a 38 percent hydrogen peroxide in-office whitening agent induced no roughness alterations of the enamel surface, even after prolonged and repeated applications.

Effect of Prevascularization on In Vivo Vascularization of Poly(Propylene fumarate)/Fibrin Scaffolds

PubMed Central

Mishra, Ruchi; Roux, Brianna M.; Posukonis, Megan; Bodamer, Emily; Brey, Eric M.; Fisher, John P.; Dean, David

2016-01-01

The importance of vascularization in the field of bone tissue engineering has been established by previous studies. The present work proposes a novel poly(propylene fumarate) (PPF)/fibrin composite scaffold for the development of vascularized neobone tissue. The effect of prevascularization (i.e., in vitro pre-culture prior to implantation) with human mesenchymal stem cells (hMSCs) and human umbilical vein endothelial cells (HUVECs) on in vivo vascularization of scaffolds was determined. Five conditions were studied: no pre-culture (NP), 1 week preculture (1P), 2 week pre-culture (2P), 3 week pre-culture (3P), and scaffolds without cells (control, C). Scaffolds were implanted subcutaneously in a severe combined immunodeficiency (SCID) mice model for 9 days. During in vitro studies, CD31 staining showed a significant increase in vascular network area over 3 weeks of culture. Vascular density was significantly higher in vivo when comparing NP to 3P groups. Immunohistochemical staining of human CD-31 expression indicated spreading of vascular networks with increasing pre-culture time. These vascular networks were perfused with mouse blood indicated by perfused lectin staining in human CD-31 positive vessels. Our results demonstrate that in vitro prevascularization supports in vivo vascularization in PPF/fibrin scaffolds. PMID:26606451

Quantitative assessment of brain glucose metabolic rates using in vivo deuterium magnetic resonance spectroscopy.

PubMed

Lu, Ming; Zhu, Xiao-Hong; Zhang, Yi; Mateescu, Gheorghe; Chen, Wei

2017-11-01

Quantitative assessment of cerebral glucose consumption rate (CMR glc ) and tricarboxylic acid cycle flux (V TCA ) is crucial for understanding neuroenergetics under physiopathological conditions. In this study, we report a novel in vivo Deuterium ( 2 H) MRS (DMRS) approach for simultaneously measuring and quantifying CMR glc and V TCA in rat brains at 16.4 Tesla. Following a brief infusion of deuterated glucose, dynamic changes of isotope-labeled glucose, glutamate/glutamine (Glx) and water contents in the brain can be robustly monitored from their well-resolved 2 H resonances. Dynamic DMRS glucose and Glx data were employed to determine CMR glc and V TCA concurrently. To test the sensitivity of this method in response to altered glucose metabolism, two brain conditions with different anesthetics were investigated. Increased CMR glc (0.46 vs. 0.28 µmol/g/min) and V TCA (0.96 vs. 0.6 µmol/g/min) were found in rats under morphine as compared to deeper anesthesia using 2% isoflurane. This study demonstrates the feasibility and new utility of the in vivo DMRS approach to assess cerebral glucose metabolic rates at high/ultrahigh field. It provides an alternative MRS tool for in vivo study of metabolic coupling relationship between aerobic and anaerobic glucose metabolisms in brain under physiopathological states.

Hepa1-6-FLuc cell line with the stable expression of firefly luciferase retains its primary properties with promising bioluminescence imaging ability.

PubMed

Li, Yasha; Liu, Mengnan; Cui, Jiejie; Yang, Ke; Zhao, Li; Gong, Mengjia; Wang, Yi; He, Yun; He, Tongchuan; Bi, Yang

2018-05-01

Reliable animal models are required for the in vivo study of the molecular mechanisms and effects of chemotherapeutic drugs in hepatocarcinoma. In vivo tracing techniques based on firefly luciferase (FLuc) may optimize the non-invasive monitoring of experimental animals. The present study established a murine Hepa1-6-FLuc cell line that stably expressed a retrovirus-delivered FLuc protein gene. The cell morphology, proliferation, migration and invasion ability of Hepa1-6-FLuc cells were the same as that of the Hepa1-6 cells, and thus is suitable to replace Hepa1-6 cells in the construction of hepatocarcinoma animal models. No differences in subcutaneous tumor mass and its pathomorphology from implanted Hepa1-6-FLuc cells were observed compared with Hepa1-6 control tumors. Bioluminescence imaging indicated that the Luc signal of the Hepa1-6-FLuc cells was consistently strengthened with increases in tumor mass; however, the Luc signal of Hepa1-6-AdFLuc became weaker and eventually disappeared during tumor development. Therefore, compared with the transient expression by adenovirus, stable expression of the FLuc gene in Hepa1-6 cells may better reflect cell proliferation and survival in vivo , and provide a reliable source for the establishment of hepatocarcinoma models.

Structure-based optimization of a series of selective BET inhibitors containing aniline or indoline groups.

PubMed

Hu, Jianping; Wang, Yingqing; Li, Yanlian; Cao, Danyan; Xu, Lin; Song, ShanShan; Damaneh, Mohammadali Soleimani; Li, Jian; Chen, Yuelei; Wang, Xin; Chen, Lin; Shen, Jingkang; Miao, Zehong; Xiong, Bing

2018-04-25

Recently, several kinase inhibitors were found to also inhibit bromodomains, providing a new strategy for the discovery of bromodomain inhibitors. Along this line, starting from PLK1-BRD4 dual inhibitor BI-2536, we discovered a new series of dihydroquinoxalin-2(1H)-one with aniline and indoline WPF binders as selective BRD4 inhibitors. They showed better BRD4-BD1 potency and negligible PLK1 kinase activity comparing with BI-2536. Additionally, dihydroquinoxalin-2(1H)-ones containing indoline group showed profound activities in molecular and cellular based assays. Throughout the study, compounds 9, 28 and 37 showed significant inhibitory activity for c-Myc or PD-L1 protein expression and mRNA transcription both at concentration of 0.2 and 1 μM. Compound 9 was found possessing the best balance of binding affinity, in vitro metabolic stability and in vivo pharmacokinetic properties. Therefore, it was selected for in vivo pharmacological study. By using MM.1S cell derived xenograft model, we confirmed compound 9 showed comparable in vivo tumor inhibition to phase II investigation drug I-BET762, which, together with the novel WPF binder, further indicated the utility of this series of BRD4 inhibitors. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Comparison of antimalarial activity of Artemisia turanica extract with current drugs in vivo.

PubMed

Taherkhani, Mahboubeh; Rustaiyan, Abdolhossein; Nahrevanian, Hossein; Naeimi, Sabah; Taherkhani, Tofigh

2013-03-01

The purpose of this study was to compare antimalarial activity of Artemisia turanica Krasch as Iranian flora with current antimalarial drugs against Plasmodium berghei in vivo in mice. Air-dried aerial parts of Iranian flora A. turanica were collected from Khorasan, northeastern Iran, extracted with Et2O/MeOH/Petrol and defatted. Toxicity of herbal extracts was assessed on male NMRI mice, and their antimalarial efficacy was compared with antimalarial drugs [artemether, chloroquine and sulfadoxinepyrimethamine (Fansidar)] on infected P. berghei animals. All the groups were investigated for parasitaemia, body weight, hepatomegaly, splenomegaly and anemia. The significance of differences was determined by Analysis of Variances (ANOVA) and Student's t-test using Graph Pad Prism software. The inhibitory effects of A. turanica extract on early decline of P. berghei parasitaemia highlights its antimalarial activity, however, this effect no longer can be observed in the late infection. This may be due to the metabolic process of A. turanica crude extract by mice and reduction of its concentration in the body. Crude extract of A. turanica represented its antisymptomatic effects by stabilization of body, liver and spleen weights. This study confirmed antimalarial effects of A. turanica extracts against murine malaria in vivo during early infection, however, there are more benefits on pathophysiological symptoms by this medication.

A cytoarchitecture-driven myelin model reveals area-specific signatures in human primary and secondary areas using ultra-high resolution in-vivo brain MRI.

PubMed

Dinse, J; Härtwich, N; Waehnert, M D; Tardif, C L; Schäfer, A; Geyer, S; Preim, B; Turner, R; Bazin, P-L

2015-07-01

This work presents a novel approach for modelling laminar myelin patterns in the human cortex in brain MR images on the basis of known cytoarchitecture. For the first time, it is possible to estimate intracortical contrast visible in quantitative ultra-high resolution MR images in specific primary and secondary cytoarchitectonic areas. The presented technique reveals different area-specific signatures which may help to study the spatial distribution of cortical T1 values and the distribution of cortical myelin in general. It may lead to a new discussion on the concordance of cyto- and myeloarchitectonic boundaries, given the absence of such concordance atlases. The modelled myelin patterns are quantitatively compared with data from human ultra-high resolution in-vivo 7T brain MR images (9 subjects). In the validation, the results are compared to one post-mortem brain sample and its ex-vivo MRI and histological data. Details of the analysis pipeline are provided. In the context of the increasing interest in advanced methods in brain segmentation and cortical architectural studies, the presented model helps to bridge the gap between the microanatomy revealed by classical histology and the macroanatomy visible in MRI. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

In vitro and in vivo characterisation of PEG-lipid-based micellar complexes of salmon calcitonin for pulmonary delivery.

PubMed

Baginski, Leonie; Gobbo, Oliviero L; Tewes, Frederic; Salomon, Johanna J; Healy, Anne Marie; Bakowsky, Udo; Ehrhardt, Carsten

2012-06-01

To investigate DSPE-PEG(2000)-based micellar formulations of salmon calcitonin (sCT) for their ability to improve pulmonary delivery. Micelles were characterised by DLS and (31)P-NMR spectroscopy. Stability against sCT degrading peptidases, trypsin, α-chymotrypsin and neutrophil elastase as well as their influence on transepithelial absorption was investigated in vitro. In vivo performance of sCT micelles was studied in an experimental model of intratracheal aerosolisation into rats. Micelles with a mean hydrodynamic diameter of 12 nm spontaneously assembled, when a total concentration of 0.02 mM of PEG-lipid and sCT (at 1:1 molar ratio) was exceeded. Nuclear magnetic resonance confirmed the presence of small micellar structures. The micellar formulation showed increased stability against enzymatic digestion. In vitro studies also showed that sCT micelles were able to enhance transepithelial absorption. Data obtained from in vivo experiments provided evidence of significantly (P < 0.05) higher mean plasma concentrations of sCT, after inhalation of micelles compared to sCT solution, at 60 and 90 min, a significantly higher AUC (inf) and a relative bioavailability of 160 ± 55% when compared to plain sCT solution. The herein described PEG-lipid micelles are promising carriers for enhanced pulmonary delivery of sCT.

Nuclear AgNOR protein enhancement in nucleoplasms of peripheral blood lymphocytes of babies/children with Down syndrome.

PubMed

Imamoglu, Nalan; Eroz, Recep; Canatan, Halit; Demirtas, Halil; Saatci, Çetin

2016-03-01

Down syndrome (DS) is one of the most common chromosomal disorders. The factors contributing to the mental retardation together with other defects in this syndrome have not been fully explained. Individuals with DS have extra rRNA gene family since they carry an extra chromosome 21. The few reports available are on the relationship between the nucleolus organizer regions (NORs) and DS phenotype. The in vivo regulation of NORs expression on the extra chromosome 21 is not completely understood. Previous studies have shown that nucleoli of lymphocytes from infants (mostly neonates) with DS contain more in vivo and in vitro nucleolar AgNOR proteins when compared with healthy infants. The objective of this study is to compare the in vivo nuclear AgNOR protein level in nucleoplasms (also called as karyoplasm) of nonstimulated peripheral blood lymphocytes from babies/children with DS and healthy controls. Peripheral blood samples obtained from 20 babies/children with DS and 20 matched healthy controls were smeared on clean glass slides and then AgNOR staining was performed. The AgNOR protein level in nucleoplasms of lymphocytes from both groups was calculated using a computer program. Nearly 100 interphase nuclei per individual were analysed. Average nuclear AgNOR protein levels in nucleoplasms of lymphocytes from babies/children with DS were found to be significantly higher than those of the controls (P < 0.001). On the basis of our present results, we propose that the increase of nuclear AgNOR protein in in vivo conditions may contribute to the formation of DS phenotypes. © 2016 Wiley Periodicals, Inc.

Preparation and in vitro and in vivo evaluation of HupA PLGA microsphere.

PubMed

Ye, Liang; Fu, Fenghua; Liu, Wanhui; Sun, Kaoxiang; Li, Youxin; He, Jie; Yu, Xin; Yu, Pengfei; Tian, Jingwei

2013-03-01

Acetylcholinesterase inhibitors (AChEIs), including Huperzine A (HupA), have been the mainstay of treatment for Alzheimer's disease (AD). However, AChEIs can cause gastrointestinal side effects, which has been related to the high Cmax and short tmax after oral administration. Clinical trials have verified that extended-release formulation with lower Cmax and prolonged tmax, such as rivastigmine patch, could perform a similar efficacy with significantly improved tolerability compared with the oral formulations. In this study, we developed an extended-release microspheres formulation of HupA (called as HAM) with poly(lactide-co-glycolide) (PLGA) as drug carrier. HAM has showed the loading rate as 1.35% (w/w) and yielded 42% with mean particle size at 72.6 μm. In vitro and in vivo pharmacokinetics studies have showed that HAM produced a relatively smooth and continuous drug concentration in 14 days. Furthermore, in vivo pharmacokinetics data have demonstrated that the Cmax was lower and the tmax was considerably later in single intramuscular administration of HAM (1,000 μg/kg) than the counterparts in single intragastric administration of HAT (75 μg/kg/d). Meanwhile, HAM has performed a continuous inhibition to brain AChE activity in normal rats and improvement of memory deficit in Aβ1-40 i.c.v. infused AD rat model for 14 days. The results have suggested that HAM has performed good extended-release properties and good prolonged pharmacological efficacy in vivo in the 2-week period, and could exert a similar efficacy with significantly lowered gastrointestinal side effects as compared with oral formulation.

Characterization of physiochemical and biological properties of an insulin/lauryl sulfate complex formed by hydrophobic ion pairing.

PubMed

Dai, Wei-Guo; Dong, Liang C

2007-05-04

An insulin/lauryl sulfate complex was prepared by hydrophobic ion pairing (HIP). The physiochemical and biological properties of the HIP complex were characterized using octanol/water partition measurement, isothermal titration calorimetry (ITC), ultraviolet-circular dichroism (UV-CD) and Fourier transform infrared spectroscopy (FTIR). Sodium dodecyl sulfate (SDS) bound to the insulin in a stoichiometric manner. The formed complex exhibited lipophilicity, and its insulin retained its native structure integrity. The in vivo bioactivity of the complex insulin was evaluated in rats by monitoring the plasma glucose level after intravenous (i.v.) injection, and the glucose level was compared with that for free insulin. The pharmacodynamic study result in rats showed that the complex insulin had in vivo bioactivity comparable to free insulin.

Teaching social-communication skills to preschoolers with autism: efficacy of video versus in vivo modeling in the classroom.

PubMed

Wilson, Kaitlyn P

2013-08-01

Video modeling is a time- and cost-efficient intervention that has been proven effective for children with autism spectrum disorder (ASD); however, the comparative efficacy of this intervention has not been examined in the classroom setting. The present study examines the relative efficacy of video modeling as compared to the more widely-used strategy of in vivo modeling using an alternating treatments design with baseline and replication across four preschool-aged students with ASD. Results offer insight into the heterogeneous treatment response of students with ASD. Additional data reflecting visual attention and social validity were captured to further describe participants' learning preferences and processes, as well as educators' perceptions of the acceptability of each intervention's procedures in the classroom setting.

Combination of high-intensity focused ultrasound irradiation and hydroxyapatite nanoparticle injection to injure normal goat liver tissue in vivo without costal bone incision.

PubMed

Liu, L; Xiao, Z; Xiao, Y; Wang, Z; Li, F; Li, M; Peng, X

2014-10-20

The aims of this study were to evaluate the in vivo safety of intravenous nano-hydroxyapatite (nano-HA), to explore how nano-HA might influence the effects of high-intensity focused ultrasound (HIFU) on normal liver tissue, and to investigate whether intravenous nano-HA could enhance HIFU for hepatocellular carcinoma ablation in a goat model. The present study, for the first time, indicated that the delivery of abundant nano-HA into the body over short periods of time could be assembled by the hepatic reticuloendothelial system, subsequently leading to a rapid rise of ultrasound-induced overheating, and ultimately resulting in enlargement of the coagulation necrotic area for ablated hepatocellular carcinoma in goats both in vivo and ex vivo. On the other hand, therapeutic doses of nano-HA were much lower than the lethal dose, and consequently presented transient and mild abnormalities of hepatic enzymes and renal function during the first 24 h after nano-HA injection. These results suggested that the combined application of nano-HA and HIFU is potentially a more effective alternative option compared to surgery for hepatocellular carcinoma local ablation in a safe and feasible manner.

Teaching Social-Communication Skills to Preschoolers with Autism: Efficacy of Video versus in Vivo Modeling in the Classroom

ERIC Educational Resources Information Center

Wilson, Kaitlyn P.

2013-01-01

Video modeling is a time- and cost-efficient intervention that has been proven effective for children with autism spectrum disorder (ASD); however, the comparative efficacy of this intervention has not been examined in the classroom setting. The present study examines the relative efficacy of video modeling as compared to the more widely-used…

Residual blood processing by centrifugation, cell salvage or ultrafiltration in cardiac surgery: effects on clinical hemostatic and ex-vivo rheological parameters.

PubMed

Vonk, Alexander B; Muntajit, Warayouth; Bhagirath, Pranav; van Barneveld, Laurentius J; Romijn, Johannes W; de Vroege, Roel; Boer, Christa

2012-10-01

The study compared the effects of three blood concentration techniques after cardiopulmonary bypass on clinical hemostatic and ex-vivo rheological parameters. Residual blood of patients undergoing elective cardiac surgery was processed by centrifugation, cell salvage or ultrafiltration, and retransfused (n = 17 per group). Study parameters included blood loss, (free) hemoglobin, hematocrit, fibrinogen and erythrocyte aggregation, deformability and 2,3-diphosphoglycerate content. Patient characteristics were similar between groups. Ultrafiltration was associated with the highest weight of the transfusion bag [649 ± 261 vs. 320 ± 134 g (centrifugation) and 391 ± 158 g (cell salvage); P < 0.01]. Cell salvage resulted in the lowest hemolysis levels in the transfusion bag. Retransfusion of cell saver blood induced the largest gain in postoperative patient hemoglobin levels when compared to centrifugation and ultrafiltration, and was associated with the largest increase in 2,3-diphosphoglycerate when compared to ultrafiltration (Δ2,3-diphosphoglycerate 1.34 ± 1.92 vs. -0.77 ± 1.56 mmol/l; P = 0.03). Cell salvage is superior with respect to postoperative hemoglobin gain and washout of free hemoglobin when compared to centrifugation or ultrafiltration.

Tumor-stem cells interactions by fluorescence imaging

NASA Astrophysics Data System (ADS)

Meleshina, Aleksandra V.; Cherkasova, Elena I.; Sergeeva, Ekaterina; Turchin, Ilya V.; Kiseleva, Ekaterina V.; Dashinimaev, Erdem B.; Shirmanova, Marina V.; Zagaynova, Elena V.

2013-02-01

Recently, great deal of interest is investigation the function of the stem cells (SC) in tumors. In this study, we studied «recipient-tumor- fluorescent stem cells » system using the methods of in vivo imaging and laser scanning microscopy (LSM). We used adipose-derived adult stem (ADAS) cells of human lentiviral transfected with the gene of fluorescent protein Turbo FP635. ADAS cells were administrated into nude mice with transplanted tumor HeLa Kyoto (human cervical carcinoma) at different stages of tumor growth (0-8 days) intravenously or into tumor. In vivo imaging was performed on the experimental setup for epi - luminescence bioimaging (IAP RAS, Nizhny Novgorod). The results of the imaging showed localization of fluorophore tagged stem cells in the spleen on day 5-9 after injection. The sensitivity of the technique may be improved by spectral separation autofluorescence and fluorescence of stem cells. We compared the results of in vivo imaging and confocal laser scanning microscopy (LSM 510 META, Carl Zeiss, Germany). Internal organs of the animals and tumor tissue were investigated. It was shown that with i.v. injection of ADAS, bright fluorescent structures with spectral characteristics corresponding to TurboFP635 protein are locally accumulated in the marrow, lungs and tumors of animals. These findings indicate that ADAS cells integrate in the animal body with transplanted tumor and can be identified by fluorescence bioimaging techniques in vivo and ex vivo.

Improved hepatoprotective activity of silymarin via encapsulation in the novel vesicular nanosystem bilosomes.

PubMed

Mohsen, Amira Mohamed; Asfour, Marwa Hasanein; Salama, Abeer A A

2017-12-01

The main objective of the present work was to formulate, characterize, and evaluate silymarin (SM)-loaded bilosomes, compared to conventional liposomes, aiming at increasing the hepatoprotective activity of the drug. SM-loaded bilosomes were prepared by thin film hydration technique employing soybean phosphatidyl choline (SPC) and different bile salts. After being subjected to different methods of characterization, SM-loaded bilosomes were investigated for their hepatoprotective activity, in CCl 4 hepatointoxicated rat model. The developed SM dispersions exhibited an entrapment efficiency ranging from 21.80 ± 2.01 to 84.54 ± 2.51% and a particle size diameter in the nanometric dimensions (413 ± 96.9 to 686.9 ± 62.38 nm), with a negative zeta potential values (<-45 mV). In vitro release study revealed a lower cumulative amount of drug released from the developed formulae, compared to free drug. Ex vivo intestinal uptake study, performed using confocal laser scanning calorimetry, revealed the superiority of bilosomal uptake compared to that of liposomes. In vivo studies revealed an enhanced hepatoprotective effect of SM-loaded bilosomes/liposomes compared to free drug. These results were in good correlation with histopathological examination. These findings support the potential use of bilosomes for improving the hepatoprotective activity of SM via oral administration.

In vivo pharmacological evaluation and efficacy study of methotrexate-encapsulated polymer-coated layered double hydroxide nanoparticles for possible application in the treatment of osteosarcoma.

PubMed

Ray, Sayantan; Saha, Suman; Sa, Biswanath; Chakraborty, Jui

2017-04-01

Considering the existing drawbacks of methotrexate (MTX) with respect to its solubility and toxicity, we incorporated it in a nanoceramic matrix, Mg-Al-layered double hydroxide (LDH) to form LDH-MTX nanoparticles, and the same was in turn encapsulated in a nontoxic and biodegradable polymer, poly (D,L-lactide-co-glycolide) (PLGA), to arrest the initial burst release and dose-dumping-related toxicity, already reported by our group. Our present study was designed to evaluate the pharmacokinetics, tissue distribution, survival rate of the test animals, and antitumor efficacy of the PLGA-LDH-MTX nanoparticles and its counterpart without LDH, PLGA-MTX nanoparticles compared with bare MTX. The median lethal dose (LD 50 ) of the former was higher, compared with bare MTX, using Balb/c nude mice, indicating it to be completely safe for use. Also, a comparative pharmacokinetic and antitumour efficacy study using MTX, PLGA-MTX, and PLGA-LDH-MTX nanoparticles in osteosarcoma-induced Balb/c nude mice in vivo demonstrated superiority of PLGA-LDH-MTX as compared to PLGA-MTX and bare MTX. The results suggest that PLGA-LDH-MTX nanoparticles might exhibit potential advantages over the present-day chemotherapy over bare MTX, for the possibility of treatment of osteosarcoma.

In vivo cardiac glucose metabolism in the high-fat fed mouse: Comparison of euglycemic–hyperinsulinemic clamp derived measures of glucose uptake with a dynamic metabolomic flux profiling approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kowalski, Greg M., E-mail: greg.kowalski@deakin.edu.au; De Souza, David P.; Risis, Steve

Rationale: Cardiac metabolism is thought to be altered in insulin resistance and type 2 diabetes (T2D). Our understanding of the regulation of cardiac substrate metabolism and insulin sensitivity has largely been derived from ex vivo preparations which are not subject to the same metabolic regulation as in the intact heart in vivo. Studies are therefore required to examine in vivo cardiac glucose metabolism under physiologically relevant conditions. Objective: To determine the temporal pattern of the development of cardiac insulin resistance and to compare with dynamic approaches to interrogate cardiac glucose and intermediary metabolism in vivo. Methods and results: Studies were conducted to determine themore » evolution of cardiac insulin resistance in C57Bl/6 mice fed a high-fat diet (HFD) for between 1 and 16 weeks. Dynamic in vivo cardiac glucose metabolism was determined following oral administration of [U-{sup 13}C] glucose. Hearts were collected after 15 and 60 min and flux profiling was determined by measuring {sup 13}C mass isotopomers in glycolytic and tricarboxylic acid (TCA) cycle intermediates. Cardiac insulin resistance, determined by euglycemic–hyperinsulinemic clamp, was evident after 3 weeks of HFD. Despite the presence of insulin resistance, in vivo cardiac glucose metabolism following oral glucose administration was not compromised in HFD mice. This contrasts our recent findings in skeletal muscle, where TCA cycle activity was reduced in mice fed a HFD. Similar to our report in muscle, glucose derived pyruvate entry into the TCA cycle in the heart was almost exclusively via pyruvate dehydrogenase, with pyruvate carboxylase mediated anaplerosis being negligible after oral glucose administration. Conclusions: Under experimental conditions which closely mimic the postprandial state, the insulin resistant mouse heart retains the ability to stimulate glucose metabolism. - Highlights: • Insulin clamp was used to determine the evolution of cardiac insulin resistance. • Clamp measures were compared to a dynamic metabolomics approach. • The clamp revealed the presence of cardiac insulin resistance after 3 weeks of HFD. • Cardiac glucose metabolism was not affected by HFD during an oral glucose challenge.« less

In vivo oxidation in remelted highly cross-linked retrievals.

PubMed

Currier, B H; Van Citters, D W; Currier, J H; Collier, J P

2010-10-20

Elimination of free radicals to prevent oxidation has played a major role in the development and product differentiation of the latest generation of highly cross-linked ultra-high molecular weight polyethylene bearing materials. In the current study, we (1) examined oxidation in a series of retrieved remelted highly cross-linked ultra-high molecular weight polyethylene bearings from a number of device manufacturers and (2) compared the retrieval results with findings for shelf-stored control specimens. The hypothesis was that radiation-cross-linked remelted ultra-high molecular weight polyethylene would maintain oxidative stability in vivo comparable with the stability during shelf storage and in published laboratory aging tests. Fifty remelted highly cross-linked ultra-high molecular weight polyethylene acetabular liners and nineteen remelted highly cross-linked ultra-high molecular weight polyethylene tibial inserts were received after retrieval from twenty-one surgeons from across the U.S. Thirty-two of the retrievals had been in vivo for two years or more. Each was measured for oxidation with use of Fourier transform infrared spectroscopy. A control series of remelted highly cross-linked ultra-high molecular weight polyethylene acetabular liners from three manufacturers was analyzed with electron paramagnetic resonance spectroscopy to measure free radical content and with Fourier transform infrared spectroscopy to measure oxidation initially and after eight to nine years of shelf storage in air. The never-implanted, shelf-aged controls had no measurable free-radical content initially or after eight to nine years of shelf storage. The never-implanted controls showed no increase in oxidation during shelf storage. Oxidation measurements showed measurable oxidation in 22% of the retrieved remelted highly cross-linked liners and inserts after an average of two years in vivo. Because never-implanted remelted highly cross-linked ultra-high molecular weight polyethylene materials had no measurable free-radical concentration and no increase in oxidation during shelf storage, these materials were expected to be oxidation-resistant in vivo. However, some remelted highly cross-linked ultra-high molecular weight polyethylene retrievals showed measurable oxidation after an average of more than two years in vivo. This apparent departure from widely expected behavior requires continued study of the process of in vivo oxidation of ultra-high molecular weight polyethylene materials.

Development and validation of in vitro-in vivo correlation (IVIVC) for estradiol transdermal drug delivery systems.

PubMed

Yang, Yang; Manda, Prashanth; Pavurala, Naresh; Khan, Mansoor A; Krishnaiah, Yellela S R

2015-07-28

The objective of this study was to develop a level A in vitro-in vivo correlation (IVIVC) for drug-in-adhesive (DIA) type estradiol transdermal drug delivery systems (TDDS). In vitro drug permeation studies across human skin were carried out to obtain the percent of estradiol permeation from marketed products. The in vivo time versus plasma concentration data of three estradiol TDDS at drug loadings of 2.0, 3.8 and 7.6mg (delivery rates of 25, 50 and 100μg/day, respectively) was deconvoluted using Wagner-Nelson method to obtain percent of in vivo drug absorption in postmenopausal women. The IVIVC between the in vitro percent of drug permeation (X) and in vivo percent of drug absorption (Y) for these three estradiol TDDS was constructed using GastroPlus® software. There was a high correlation (R(2)=1.0) with a polynomial regression of Y=-0.227X(2)+0.331X-0.001. These three estradiol TDDS were used for internal validation whereas another two products of the same formulation design (with delivery rates of 60 and 100μg/day) were used for external validation. The predicted estradiol serum concentrations (convoluted from in vitro skin permeation data) were compared with the observed serum concentrations for the respective products. The developed IVIVC model passed both the internal and external validations as the prediction errors (%PE) for Cmax and AUC were less than 15%. When another marketed estradiol TDDS with a delivery rate of 100μg/day but with a slight variation in formulation design was chosen, it did not pass external validation indicating the product-specific nature of IVIVC model. Results suggest that the IVIVC model developed in this study can be used to successfully predict the in vivo performance of the same estradiol TDDS with in vivo delivery rates ranging from 25 to 100μg/day. Published by Elsevier B.V.

Cytokeratin expression of engrafted three-dimensional culture tissues using epithelial cells derived from porcine periodontal ligaments.

PubMed

Yamada, Rie; Kitajima, Kayoko; Arai, Kyoko; Igarashi, Masaru

2014-09-01

This study investigated the differentiation and proliferation of epithelial cells derived from periodontal ligaments after three-dimensional culture using collagen gel with fibroblasts in vitro and in vivo. Epithelial cells and fibroblasts were derived from porcine periodontal ligaments. Epithelial cells were labeled using a fluorescent red membrane marker (PKH-26GL) and were seeded onto collagen gel with fibroblasts, followed by incubation in an air-liquid interface for 7 days. Three-dimensional cultures were grafted onto the backs of nude mice and removed at 1, 7, and 14 days after surgery (in vivo model). Unfixed sections (5 μm) were used to detect the presence of red fluorescent cells. Paraffin sections were analyzed histologically and immunohistochemically. Specimens were compared with three-dimensional culture tissues at 8, 14 and 21 days (in vitro model). Grafted three-dimensional cultures formed a stratified epithelial structure similar to skin in vivo. Epithelial cells were sequenced in basal-layer-like structures at 14 days in vivo. Immunohistochemical findings showed that the expression of cytokeratin was detected in the epithelial layer in in vitro and in vivo models. Ck8 + 18 + 19 was expressed in the upper epithelial layer in the in vitro model at 14 and 21 days, but not in vivo. Involucrin was expressed in the certified layers in vitro at 14 days, but not in vivo. Laminin was detected at the dermo-epidermal junction in vivo at 7 and 14 days, but not in vitro. These results suggest that differentiation of three-dimensional culture tissues differs in vivo and in vitro. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Improving reconstituted HDL composition for efficient post-ischemic reduction of ischemia reperfusion injury.

PubMed

Brulhart-Meynet, Marie-Claude; Braunersreuther, Vincent; Brinck, Jonas; Montecucco, Fabrizio; Prost, Jean-Christophe; Thomas, Aurelien; Galan, Katia; Pelli, Graziano; Pedretti, Sarah; Vuilleumier, Nicolas; Mach, François; Lecour, Sandrine; James, Richard W; Frias, Miguel A

2015-01-01

New evidence shows that high density lipoproteins (HDL) have protective effects beyond their role in reverse cholesterol transport. Reconstituted HDL (rHDL) offer an attractive means of clinically exploiting these novel effects including cardioprotection against ischemia reperfusion injury (IRI). However, basic rHDL composition is limited to apolipoprotein AI (apoAI) and phospholipids; addition of bioactive compound may enhance its beneficial effects. The aim of this study was to investigate the role of rHDL in post-ischemic model, and to analyze the potential impact of sphingosine-1-phosphate (S1P) in rHDL formulations. The impact of HDL on IRI was investigated using complementary in vivo, ex vivo and in vitro IRI models. Acute post-ischemic treatment with native HDL significantly reduced infarct size and cell death in the ex vivo, isolated heart (Langendorff) model and the in vivo model (-48%, p<0.01). Treatment with rHDL of basic formulation (apoAI + phospholipids) had a non-significant impact on cell death in vitro and on the infarct size ex vivo and in vivo. In contrast, rHDL containing S1P had a highly significant, protective influence ex vivo, and in vivo (-50%, p<0.01). This impact was comparable with the effects observed with native HDL. Pro-survival signaling proteins, Akt, STAT3 and ERK1/2 were similarly activated by HDL and rHDL containing S1P both in vitro (isolated cardiomyocytes) and in vivo. HDL afford protection against IRI in a clinically relevant model (post-ischemia). rHDL is significantly protective if supplemented with S1P. The protective impact of HDL appears to target directly the cardiomyocyte.

Remote-loading of liposomes with manganese-52 and in vivo evaluation of the stabilities of 52Mn-DOTA and 64Cu-DOTA using radiolabelled liposomes and PET imaging.

PubMed

Jensen, Andreas I; Severin, Gregory W; Hansen, Anders E; Fliedner, Frederikke P; Eliasen, Rasmus; Parhamifar, Ladan; Kjær, Andreas; Andresen, Thomas L; Henriksen, Jonas R

2018-01-10

Liposomes are nanoparticles used in drug delivery that distribute over several days in humans and larger animals. Radiolabeling with long-lived positron emission tomography (PET) radionuclides, such as manganese-52 ( 52 Mn, T½=5.6days), allow the imaging of this biodistribution. We report optimized protocols for radiolabeling liposomes with 52 Mn, through both remote-loading and surface labeling. For comparison, liposomes were also remote-loaded and surface labeled with copper-64 ( 64 Cu, T½=12.7h) through conventional means. The chelator DOTA was used in all cases. The in vivo stability of radiometal chelates is widely debated but studies that mimic a realistic in vivo setting are lacking. Therefore, we employed these four radiolabeled liposome types as platforms to demonstrate a new concept for such in vivo evaluation, here of the chelates 52 Mn-DOTA and 64 Cu-DOTA. This was done by comparing "shielded" remote-loaded with "exposed" surface labeled variants in a CT26 tumor-bearing mouse model. Remote loading (90min at 55°C) and surface labeling (55°C for 2h) of 52 Mn gave excellent radiolabeling efficiencies of 97-100% and 98-100% respectively, and the liposome biodistribution was imaged by PET for up to 8days. Liposomes with surface-conjugated 52 Mn-DOTA exhibited a significantly shorter plasma half-life (T ½ =14.4h) when compared to the remote-loaded counterpart (T ½ =21.3h), whereas surface-conjugated 64 Cu-DOTA cleared only slightly faster and non-significantly, when compared to remote-loaded (17.2±2.9h versus 20.3±1.2h). From our data, we conclude the successful remote-loading of liposomes with 52 Mn, and furthermore that 52 Mn-DOTA may be unstable in vivo whereas 64 Cu-DOTA appears suitable for quantitative imaging. Copyright © 2017 Elsevier B.V. All rights reserved.

Low rate loading-induced convection enhances net transport into the intervertebral disc in vivo.

PubMed

Gullbrand, Sarah E; Peterson, Joshua; Mastropolo, Rosemarie; Roberts, Timothy T; Lawrence, James P; Glennon, Joseph C; DiRisio, Darryl J; Ledet, Eric H

2015-05-01

The intervertebral disc primarily relies on trans-endplate diffusion for the uptake of nutrients and the clearance of byproducts. In degenerative discs, diffusion is often diminished by endplate sclerosis and reduced proteoglycan content. Mechanical loading-induced convection has the potential to augment diffusion and enhance net transport into the disc. The ability of convection to augment disc transport is controversial and has not been demonstrated in vivo. To determine if loading-induced convection can enhance small molecule transport into the intervertebral disc in vivo. Net transport was quantified via postcontrast enhanced magnetic resonance imaging (MRI) into the discs of the New Zealand white rabbit lumbar spine subjected to in vivo cyclic low rate loading. Animals were administered the MRI contrast agent gadodiamide intravenously and subjected to in vivo low rate loading (0.5 Hz, 200 N) via a custom external loading apparatus for either 2.5, 5, 10, 15, or 20 minutes. Animals were then euthanized and the lumbar spines imaged using postcontrast enhanced MRI. The T1 constants in the nucleus, annulus, and cartilage endplates were quantified as a measure of gadodiamide transport into the loaded discs compared with the adjacent unloaded discs. Microcomputed tomography was used to quantify subchondral bone density. Low rate loading caused the rapid uptake and clearance of gadodiamide in the nucleus compared with unloaded discs, which exhibited a slower rate of uptake. Relative to unloaded discs, low rate loading caused a maximum increase in transport into the nucleus of 16.8% after 5 minutes of loading. Low rate loading increased the concentration of gadodiamide in the cartilage endplates at each time point compared with unloaded levels. Results from this study indicate that forced convection accelerated small molecule uptake and clearance in the disc induced by low rate mechanical loading. Low rate loading may, therefore, be therapeutic to the disc as it may enhance the nutrient uptake and waste product clearance. Copyright © 2015 Elsevier Inc. All rights reserved.

Homologous upregulation of sst2 somatostatin receptor expression in the rat arcuate nucleus in vivo.

PubMed

Tannenbaum, G S; Turner, J; Guo, F; Videau, C; Epelbaum, J; Beaudet, A

2001-07-01

In vitro studies using various cell systems have provided conflicting results regarding homologous regulation of somatostatin (SRIH) receptors, and information on whether SRIH regulates the expression of its own receptors in vivo is lacking. In the present study we examined, by in situ hybridization, the effects of pretreatment with the sst2-preferring SRIH analog, octreotide, in vivo, on mRNA levels of two SRIH receptor subtypes, sst1 and sst2, in rat brain and pituitary. (125)I-[DTrp(8)]-SRIH binding was also measured in these regions. Three hours after the iv injection of 50 microg octreotide to conscious adult male rats, there was a 46% increase (p < 0.01) in the labeling density of sst2 mRNA-expressing cells in the hypothalamic arcuate nucleus compared to normal saline-pretreated controls, but not in any of the other brain regions examined. Computer-assisted image analysis revealed that 3 h exposure to octreotide significantly (p < 0.01) augmented both the number and labeling density of sst2 mRNA-expressing cells in the arcuate nucleus, compared to those in saline-treated controls. By contrast, within the anterior pituitary gland, in vivo exposure to octreotide did not affect the expression of sst2 mRNA. No changes in sst1 mRNA-expressing cells were observed after octreotide treatment in any of the regions measured, indicating that the observed effects were homologous, i.e. specific of the receptor subtype stimulated. Octreotide pretreatment was also without effect on the density of (125)I-[DTrp(8)]-SRIH binding in either the arcuate nucleus or pituitary. These results demonstrate, for the first time, that SRIH preexposure in vivo upregulates the expression of a subtype of its own receptors, sst2, within the central nervous system. They further suggest that pretreatment with SRIH in vivo does not cause sst2 receptor desensitization in arcuate nucleus and pituitary. Such homologous regulatory mechanisms may play an important role in the neuroendocrine control of growth hormone (GH) secretion by the arcuate nucleus. Copyright 2001 S. Karger AG, Basel

Development of wound healing models to study TGFβ3's effect on SMA.

PubMed

Sriram, Sriniwas; Tran, Jennifer A; Guo, Xiaoqing; Hutcheon, Audrey E K; Kazlauskas, Andrius; Zieske, James D

2017-08-01

The goal of this study was to test the efficacy of transforming growth factor beta 3 (TGFβ3) in reducing α-smooth muscle actin (SMA) expression in two models-an ex vivo organ culture and an in vitro 3D cell construct-both of which closely mimic an in vivo environment. For the ex vivo organ culture system, a central 6.0 mm corneal keratectomy was performed on freshly excised rabbit globes The corneas were then excised, segregated into groups treated with 1.0 ng/ml TGFβ1 or β3 (T1 or T3, respectively), and cultured for 2 weeks. The corneas were assessed for levels of haze and analyzed for SMA mRNA levels. For the 3D in vitro model, rabbit corneal fibroblasts (RbCFs) were cultured for 4 weeks on poly-transwell membranes in Eagle's minimum essential media (EMEM) + 10% FBS + 0.5 mM vitamin C ± 0.1 ng/ml T1 or T3. At the end of 4 weeks, the constructs were processed for analysis by indirect-immunofluorescence (IF) and RT-qPCR. The RT-qPCR data showed that SMA mRNA expression in T3 samples for both models was significantly lower (p < 0.05) than T1 treatment (around 3-fold in ex vivo and 2-fold in constructs). T3 also reduced the amount of scarring in ex vivo corneas as compared with the T1 samples. IF data from RbCF constructs confirmed that T3-treated samples had up to 4-fold (p < 0.05) lower levels of SMA protein expression than samples treated with T1. These results show that T3 when compared to T1 decreases the expression of SMA in both ex vivo organ culture and in vitro 3D cell construct models. Understanding the mechanism of T3's action in these systems and how they differ from simple cell culture models, may potentially help in developing T3 as an anti-scarring therapy. Copyright © 2017. Published by Elsevier Ltd.

TH-C-18A-09: Exam and Patient Parameters Affecting the DNA Damage Response Following CT Studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elgart, S; Adibi, A; Bostani, M

Purpose: To identify exam and patient parameters affecting the biological response to CT studies using in vivo and ex vivo blood samples. Methods: Blood samples were collected under IRB approval from 16 patients undergoing clinically-indicated CT exams. Blood was procured prior to, immediately after and 30minutes following irradiation. A sample of preexam blood was placed on the patient within the exam region for ex vivo analysis. Whole blood samples were fixed immediately following collection and stained for γH2AX to assess DNA damage response (DDR). Median fluorescence of treated samples was compared to non-irradiated control samples for each patient. Patients weremore » characterized by observed biological kinetic response: (a) fast — phosphorylation increased by 2minutes and fell by 30minutes, (b) slow — phosphorylation continued to increase to 30minutes and (c) none — little change was observed or irradiated samples fell below controls. Total dose values were normalized to exam time for an averaged dose-rate in dose/sec for each exam. Relationships between patient biological responses and patient and exam parameters were investigated. Results: A clearer dose response at 30minutes is observed for young patients (<61yoa; R2>0.5) compared to old patients (>61yoa; R{sup 2}<0.11). Fast responding patients were significantly younger than slow responding patients (p<0.05). Unlike in vivo samples, age did not significantly affect the patient response ex vivo. Additionally, fast responding patients received exams with significantly smaller dose-rate than slow responding patients (p<0.05). Conclusion: Age is a significant factor in the biological response suggesting that DDR may be more rapid in a younger population and slower as the population ages. Lack of an agerelated response ex vivo suggests a systemic response to radiation not present when irradiated outside the body. Dose-rate affects the biological response suggesting that patient response may be related to scan timing and dose delivery within an exam protocol. All authors receive(d) funding from a Master Research Agreement from Siemens Healthcare with UCLA Radiological Sciences.« less

In vivo near-infrared fluorescence imaging of CD105 expression during tumor angiogenesis.

PubMed

Yang, Yunan; Zhang, Yin; Hong, Hao; Liu, Glenn; Leigh, Bryan R; Cai, Weibo

2011-11-01

Angiogenesis is an indispensable process during tumor development. The currently accepted standard method for quantifying tumor angiogenesis is to assess microvessel density (MVD) based on CD105 staining, which is an independent prognostic factor for survival in patients with most solid tumor types. The goal of this study is to evaluate tumor angiogenesis in a mouse model by near-infrared fluorescence (NIRF) imaging of CD105 expression. TRC105, a human/murine chimeric anti-CD105 monoclonal antibody, was conjugated to an NIRF dye (IRDye 800CW; Ex: 778 nm; Em: 806 nm). FACS analysis and microscopy studies were performed to compare the CD105 binding affinity of TRC105 and 800CW-TRC105. In vivo/ex vivo NIRF imaging, blocking studies, and ex vivo histology were performed on 4T1 murine breast tumor-bearing mice to evaluate the ability of 800CW-TRC105 to target tumor angiogenesis. Another chimeric antibody, cetuximab, was used as an isotype-matched control. FACS analysis of human umbilical vein endothelial cells (HUVECs) revealed no difference in CD105 binding affinity between TRC105 and 800CW-TRC105, which was further validated by fluorescence microscopy. 800CW conjugation of TRC105 was achieved in excellent yield (> 85%), with an average of 0.4 800CW molecules per TRC105. Serial NIRF imaging after intravenous injection of 800CW-TRC105 revealed that the 4T1 tumor could be clearly visualized as early as 30 min post-injection. Quantitative region of interest (ROI) analysis showed that the tumor uptake peaked at about 16 h post-injection. Based on ex vivo NIRF imaging at 48 h post-injection, tumor uptake of 800CW-TRC105 was higher than most organs, thus providing excellent tumor contrast. Blocking experiments, control studies with 800CW-cetuximab and 800CW, as well as ex vivo histology all confirmed the in vivo target specificity of 800CW-TRC105. This is the first successful NIRF imaging study of CD105 expression in vivo. Fast, prominent, persistent, and CD105-specific uptake of the probe during tumor angiogenesis was observed in a mouse model. 800CW-TRC105 may be used in the clinic for imaging tumor angiogenesis within the lesions close to the skin surface, tissues accessible by endoscopy, or during image-guided surgery.

Flexible, 31 channel breast coil for enhanced parallel imaging performance at 3T

PubMed Central

Hancu, Ileana; Fiveland, Eric; Park, Keith; Giaquinto, Randy O.; Rohling, Kenneth; Wiesinger, Florian

2015-01-01

Purpose To design, build and characterize the performance of a novel 3T, 31 channel breast coil. Methods A flexible breast coil, accommodating all breast sizes while preserving close to unity filling factors in all configurations, was designed and built. Its performance was compared to the performance of the current state-of-the-art, 16 channel breast coil (Sentinelle coil, Hologic, Bedford, MA, USA), in phantoms and in vivo. Results Better axilla coverage and lower inter-coil coupling (12% vs. 26%, as characterized by the average off-diagonal elements of the noise correlation matrix) was exhibited by our 31 channel coil compared to the 16 channel coil. Breast area SNR increases of 68% (phantom) and 28 ± 31% (in vivo) were demonstrated in the 3 volunteers studied when the 31 channel coil was used. For the 31 channel/16 channel arrays, respectively, two dimensional acceleration factors of L/R × S/I = 4.3 × 2.4 resulted in average g-factors of 1.10/1.68 (in vitro) and 1.28/2.75 (in vivo); acceleration factors of L/R × A/P = 3.0 × 2.8 resulted in average g-factors of 1.06/1.54 (in vitro) and 1.05/1.12 (in vivo). Conclusion A high performance breast coil was built; its capabilities were demonstrated in phantom and normal volunteer imaging experiments. PMID:25772214

Two-photon excited fluorescence microscopy application for ex vivo investigation of ocular fundus samples

NASA Astrophysics Data System (ADS)

Peters, Sven; Hammer, Martin; Schweitzer, Dietrich

2011-07-01

Two-photon excited fluorescence (TPEF) imaging of ocular tissue has recently become a promising tool in ophthalmology for diagnostic and research purposes. The feasibility and the advantages of TPEF imaging, namely deeper tissue penetration and improved high-resolution imaging of microstructures, have been demonstrated lately using human ocular samples. The autofluorescence properties of endogenous fluorophores in ocular fundus tissue are well known from spectrophotometric analysis. But fluorophores, especially when it comes to fluorescence lifetime, typically display a dependence of their fluorescence properties on local environmental parameters. Hence, a more detailed investigation of ocular fundus autofluorescence ideally in vivo is of utmost interest. The aim of this study is to determine space-resolved the stationary and time-resolved fluorescence properties of endogenous fluorophores in ex vivo porcine ocular fundus samples by means of two-photon excited fluorescence spectrum and lifetime imaging microscopy (FSIM/FLIM). By our first results, we characterized the autofluorescence of individual anatomical structures of porcine retina samples excited at 760 nm. The fluorescence properties of almost all investigated retinal layers are relatively homogenous. But as previously unknown, ganglion cell bodies show a significantly shorter fluorescence lifetime compared to the adjacent mueller cells. Since all retinal layers exhibit bi-exponential autofluorescence decays, we were able to achieve a more precise characterization of fluorescence properties of endogenous fluorophores compared to a present in vivo FLIM approach by confocal scanning laser ophthalmoscope (cSLO).

Comparison of a New High-Frequency Electric Welding System for Intestinal Closure with Hand-Sewn In Vivo Pig Model.

PubMed

Han, Shuai; Cai, Zhai; Ning, Xuanjing; He, Linyun; Chen, Jun; Huang, Zonghai; Zhou, Huabin; Huang, Dequn; Zhang, Pusheng; Li, Zhou

2015-08-01

Various surgical small intestinal anastomosis methods are in current use, but improvements are always desired. Thus, we compared the feasibility, effectiveness, and safety of a new high-frequency electric welding (HFEW) system for sealing the small bowel versus a hand-sewn in vivo pig model. The 96 bowel segments of three pigs were randomized to be sutured either by the HFEW-300 PATONMED device (E.O. Paton Electric Welding Institute of the National Academy of Sciences of Ukraine, Kiev, Ukraine) or hand-sewn, and mucosa-to-mucosa fusions were subjected in vivo testing in the pigs. Bursting pressures, suture time, thermal damage, and the temperature of sealed ends were measured. Segments that had been treated with a hand-sutured ligature or double-sealed with HFEW were compared. Burst pressure was significantly higher in the hand-sutured group than in the HFEW group (136.2 mm Hg versus 75.8 mm Hg, P<.01). All 48 pig small bowels closed by the HFEW-300 generator showed a success rate of 100.0%. The closing time in the HFEW group was significantly shorter (P<.01). The pathological changes of the closed ends were mainly presented as acute thermal- and pressure-induced injuries. Outcomes of the current in vivo study suggest that HFEW is an effective and safe method for ligation of the small bowel in pigs.

UCEPR: Ultrafast localized CEST-spectroscopy with PRESS in phantoms and in vivo.

PubMed

Liu, Zheng; Dimitrov, Ivan E; Lenkinski, Robert E; Hajibeigi, Asghar; Vinogradov, Elena

2016-05-01

Chemical exchange saturation transfer (CEST) is a contrast mechanism enhancing low-concentration molecules through saturation transfer from their exchangeable protons to bulk water. Often many scans are acquired to form a Z-spectrum, making the CEST method time-consuming. Here, an ultrafast localized CEST-spectroscopy with PRESS (UCEPR) is proposed to obtain the entire Z-spectrum of a voxel using only two scans, significantly accelerating CEST. The approach combines ultrafast nonlocalized CEST spectroscopy with localization using PRESS. A field gradient is applied concurrently with the saturation pulse producing simultaneous saturation of all Z-spectrum frequencies that are also spatially encoded. A readout gradient during data acquisition resolves the spatial dependence of the CEST responses into frequency. UCEPR was tested on a 3T scanner both in phantoms and in vivo. In phantoms, a fast Z-spectroscopy acquisition of multiple pH-variant iopamidol samples was achieved with four- to seven-fold acceleration as compared to the conventional CEST methods. In vivo, amide proton transfer (APT) in white matter of healthy human brain was measured rapidly in 48 s and with high frequency resolution (≤ 0.2 ppm). Compared with conventional CEST methods, UCEPR has the advantage of rapidly acquiring high-resolution Z-spectra. Potential in vivo applications include ultrafast localized Z-spectroscopy, quantitative, or dynamic CEST studies. © 2015 Wiley Periodicals, Inc.

Analysis of Carbon Fiber Reinforced PEEK Hinge Mechanism Articulation Components in a Rotating Hinge Knee Design: A Comparison of In Vitro and Retrieval Findings.

PubMed

Schierjott, Ronja A; Giurea, Alexander; Neuhaus, Hans-Joachim; Schwiesau, Jens; Pfaff, Andreas M; Utzschneider, Sandra; Tozzi, Gianluca; Grupp, Thomas M

2016-01-01

Carbon fiber reinforced poly-ether-ether-ketone (CFR-PEEK) represents a promising alternative material for bushings in total knee replacements, after early clinical failures of polyethylene in this application. The objective of the present study was to evaluate the damage modes and the extent of damage observed on CFR-PEEK hinge mechanism articulation components after in vivo service in a rotating hinge knee (RHK) system and to compare the results with corresponding components subjected to in vitro wear tests. Key question was if there were any similarities or differences between in vivo and in vitro damage characteristics. Twelve retrieved RHK systems after an average of 34.9 months in vivo underwent wear damage analysis with focus on the four integrated CFR-PEEK components and distinction between different damage modes and classification with a scoring system. The analysis included visual examination, scanning electron microscopy, and energy dispersive X-ray spectroscopy, as well as surface roughness and profile measurements. The main wear damage modes were comparable between retrieved and in vitro specimens ( n = 3), whereby the size of affected area on the retrieved components showed a higher variation. Overall, the retrieved specimens seemed to be slightly heavier damaged which was probably attributable to the more complex loading and kinematic conditions in vivo.

In vivo inhibition of circulating tumor cells by two apoptosis-promoting circular aptamers with enhanced specificity.

PubMed

Dong, Haiyan; Han, Longyu; Wang, Jie; Xie, Jingjing; Gao, Yu; Xie, Fangwei; Jia, Lee

2018-05-07

Circulating tumor cells (CTCs) are known as the root cause of cancer metastasis that accounts for 90% of cancer death. Owing to the rarity of blood CTCs and their microenvironmental complexity, the existing biotechnology could not precisely capture and apoptosize CTCs in vivo for cancer metastasis prevention. Here, we designed two double strand circular aptamers aimed to simultaneously target MUC1 and HER2 surface biomarkers on mesenchymal cancer cells. The circular aptamers are composed of a capture arm for binding and seizing CTCs and a circular body for resisting degradation by exonucleases. We conjugated the two circular aptamers onto dendrimer PAMAM G4.5 (dcAp1-G-dcAp2), and the conjugate entity showed both significantly-enhanced biostability in serum for days compared with their linear counterparts and capture specificity in RBC (1:10 8 ) compared with their single circular aptamers. dcAp1-G-dcAp2 apoptosized the targeted cells and inhibited their bioenergetic activities significantly by lowing △Ψm, ATP and lactate productions while increasing ROS production. dcAp1-G-dcAp2 captured CTCs in mice in vivo and in patient blood. This study lays the foundation for developing multiple biostable circular aptamers and conjugating them together to precisely capture and apoptosize mesenchymal CTCs in vivo. Copyright © 2018 Elsevier B.V. All rights reserved.

Liposomal buccal mucoadhesive film for improved delivery and permeation of water-soluble vitamins.

PubMed

Abd El Azim, Heba; Nafee, Noha; Ramadan, Alyaa; Khalafallah, Nawal

2015-07-05

This study aims at improving the buccal delivery of vitamin B6 (VB6) as a model highly water-soluble, low permeable vitamin. Two main strategies were combined; first VB6 was entrapped in liposomes, which were then formulated as mucoadhesive film. Both plain and VB6-loaded liposomes (LPs) containing Lipoid S100 and propylene glycol (∼ 200 nm) were then incorporated into mucoadhesive film composed of SCMC and HPMC. Results showed prolonged release of VB6 (72.65%, T50% diss 105 min) after 6h from LP-film compared to control film containing free VB6 (96.37%, T50% diss 30 min). Mucoadhesion was assessed both ex vivo on chicken pouch and in vivo in human. Mucoadhesive force of 0.2N and residence time of 4.4h were recorded. Ex vivo permeation of VB6, across chicken pouch mucosa indicated increased permeation from LP-systems compared to corresponding controls. Interestingly, incorporation of the vesicles in mucoadhesive film reduced the flux by 36.89% relative to LP-dispersion. Meanwhile, both films provided faster initial permeation than the liquid forms. Correlating the cumulative percent permeated ex vivo with the cumulative percent released in vitro indicated that LPs retarded VB6 release but improved permeation. These promising results represent a step forward in the field of buccal delivery of water-soluble vitamins. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparison of in vivo and in vitro survival and fecundity rates of the poultry red mite, Dermanyssus gallinae.

PubMed

Arkle, S; George, D R; Guy, J H; Sparagano, O A E

2010-04-01

To assist in the testing of possible antigens in developing a vaccine against the poultry red mite (Dermanyssus gallinae De Geer), a rapid and reliable in vitro screening method is critical. This short paper describes how D. gallinae survival and fecundity rates in an in vivo feeding device compared to that of mites fed using an in vitro method. Results showed that survival of fed D. gallinae females and mites overall was greater in vitro, although there was no difference between male survival and fecundity between in vivo and in vitro designs. The in vitro feeding device described therefore has the potential to provide reliable results, comparable to those obtained by in vivo testing, to allow for the rapid screening of D. gallinae antigens. Copyright 2009 Elsevier Ltd. All rights reserved.

Curcumin-loaded solid lipid nanoparticles with Brij78 and TPGS improved in vivo oral bioavailability and in situ intestinal absorption of curcumin.

PubMed

Ji, Hongyu; Tang, Jingling; Li, Mengting; Ren, Jinmei; Zheng, Nannan; Wu, Linhua

2016-01-01

The present study was to formulate curcumin solid lipid nanoparticles (Cur-SLNs) with P-gp modulator excipients, TPGS and Brij78, to enhance the solubility and bioavailability of curcumin. The formulation was optimized by Plackett-Burman screening design and Box-Behnken experiment design. Then physiochemical properties, entrapment efficiency and in vitro release of Cur-SLNs were characterized. In vivo pharmacokinetics study and in situ single-pass intestinal perfusion were performed to investigate the effects of Cur-SLNs on the bioavailability and intestinal absorption of curcumin. The optimized formulations showed an average size of 135.3 ± 1.5 nm with a zeta potential value of -24.7 ± 2.1 mV and 91.09% ± 1.23% drug entrapment efficiency, meanwhile displayed a sustained release profile. In vivo pharmacokinetic study showed AUC0→t for Cur-SLNs was 12.27-folds greater than curcumin suspension and the relative bioavailability of Cur-SLNs was 942.53%. Meanwhile, Tmax and t(1/2) of curcumin for Cur-SLNs were both delayed comparing to the suspensions (p < 0.01). The in situ intestinal absorption study revealed that the effective permeability (Peff) value of curcumin for SLNs was significantly improved (p < 0.01) comparing to curcumin solution. Cur-SLNs with TPGS and Brij78 could improve the oral bioavailability and intestinal absorption of curcumin effectively.

Interaction of D-LSD with binding sites in brain: a study in vivo and in vitro

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ebersole, B.L.J.

The localization of (/sup 3/H)-d-lysergic acid diethylamide ((/sup 3/H)LSD) binding sites in the mouse brain was compared in vivo and in vitro. Radioautography of brain sections incubated with (/sup 3/H)LSD in vitro revealed substantial specific (/sup 3/H)LSD binding in cortical layers III-IV and areas CA1 and dentate gyrus in hippocampus. In contrast, in brain sections from animals that received (/sup 3/H)LSD in vivo, binding in hippocampus was scant and diffuse, although the pattern of labeling in cortex was similar to that seen in vitro. The low specific binding in hippocampus relative to cortex was confirmed by homogenate filtration studies ofmore » brain areas from mice that received injections of (/sup 3/H)LSD. Time-course studies established that peak specific binding at ten minutes was the same in cortex and hippocampus. At all times, binding in hippocampus was about one-third of that in cortex; in contrast, the concentration of free (/sup 3/H)LSD did not vary between regions. This finding was unexpected, because binding studies in vitro in membrane preparations indicated that the density and affinity of (/sup 3/H)LSD binding sites were similar in both brain regions. Saturation binding studies in vivo showed that the lower amount of (/sup 3/H)LSD binding in hippocampus was attributable to a lower density of sites labeled by (/sup 3/H)LSD. The pharmacological identify of (/sub 3/H)LSD binding sites in vivo may be relevant to the hallucinogenic properties of LSD and of other related hallucinogens.« less

The use of in vitro technologies coupled with high resolution accurate mass LC-MS for studying drug metabolism in equine drug surveillance.

PubMed

Scarth, James P; Spencer, Holly A; Timbers, Sarah E; Hudson, Simon C; Hillyer, Lynn L

2010-01-01

The detection of drug abuse in horseracing often requires knowledge of drug metabolism, especially if urine is the matrix of choice. In this study, equine liver/lung microsomes/S9 tissue fractions were used to study the phase I metabolism of eight drugs of relevance to equine drug surveillance (acepromazine, azaperone, celecoxib, fentanyl, fluphenazine, mepivacaine, methylphenidate and tripelennamine). In vitro samples were analyzed qualitatively alongside samples originating from in vivo administrations using LC-MS on a high resolution accurate mass Thermo Orbitrap Discovery instrument and by LC-MS/MS on an Applied Biosystems Sciex 5500 Q Trap.Using high resolution accurate mass full-scan analysis on the Orbitrap, the in vitro systems were found to generate at least the two most abundant phase I metabolites observed in vitro for all eight drugs studied. In the majority of cases, in vitro experiments were also able to generate the minor in vivo metabolites and sometimes metabolites that were only observed in vitro. More detailed analyses of fentanyl incubates using LC-MS/MS showed that it was possible to generate good quality spectra from the metabolites generated in vitro. These data support the suggestion of using in vitro incubates as metabolite reference material in place of in vivo post-administration samples in accordance with new qualitative identification guidelines in the 2009 International Laboratory Accreditation Cooperation-G7 (ILAC-G7) document.In summary, the in vitro and in vivo phase I metabolism results reported herein compare well and demonstrate the potential of in vitro studies to compliment, refine and reduce the existing equine in vivo paradigm. © 2010 John Wiley & Sons, Ltd.

QbD-Oriented Development and Characterization of Effervescent Floating-Bioadhesive Tablets of Cefuroxime Axetil.

PubMed

Bansal, Sanjay; Beg, Sarwar; Garg, Babita; Asthana, Abhay; Asthana, Gyati S; Singh, Bhupinder

2016-10-01

The objective of the present studies was systematic development of floating-bioadhesive gastroretentive tablets of cefuroxime axetil employing rational blend of hydrophilic polymers for attaining controlled release drug delivery. As per the QbD-based approach, the patient-centric target product profile and quality attributes of tablet were earmarked, and preliminary studies were conducted for screening the suitability of type of polymers, polymer ratio, granulation technique, and granulation time for formulation of tablets. A face-centered cubic design (FCCD) was employed for optimization of the critical material attributes, i.e., concentration of release controlling polymers, PEO 303 and HPMC K100 LV CR, and evaluating in vitro buoyancy, drug release, and ex vivo mucoadhesion strength. The optimized formulation was embarked upon through numerical optimization, which yield excellent floatation characteristic with drug release control (i.e., T 60% > 6 h) and bioadhesion strength. Drug-excipient compatibility studies through FTIR and P-XRD revealed the absence of any interaction between the drug and polymers. In vivo evaluation of the gastroretentive characteristics through X-ray imaging and in vivo pharmacokinetic studies in rabbits revealed significant extension in the rate of drug absorption (i.e., T max, K a, and MRT) from the optimized tablet formulation as compared to the marketed formulation. Successful establishment of various levels of in vitro/in vivo correlations (IVIVC) substantiated high degree of prognostic ability of in vitro dissolution conditions in predicting the in vivo performance. In a nutshell, the studies demonstrate successful development of the once-a-day gastroretentive formulations of cefuroxime axetil with controlled drug release profile and improved compliance.

Antimalarial activity of novel 4-aminoquinolines active against drug resistant strains.

PubMed

Kondaparla, Srinivasarao; Soni, Awakash; Manhas, Ashan; Srivastava, Kumkum; Puri, Sunil K; Katti, S B

2017-02-01

In the present study we have synthesized a new class of 4-aminoquinolines and evaluated against Plasmodium falciparum in vitro (3D7-sensitive strain & K1-resistant strain) and Plasmodium yoelii in vivo (N-67 strain). Among the series, eleven compounds (5, 6, 7, 8, 9, 11, 12, 13, 14, 15 and 21) showed superior antimalarial activity against K1 strain as compared to CQ. In addition, all these analogues showed 100% suppression of parasitemia on day 4 in the in vivo mouse model against N-67 strain when administered orally. Further, biophysical studies suggest that this series of compounds act on heme polymerization target. Copyright © 2016 Elsevier Inc. All rights reserved.

Evaluation of Electrospun Nanofiber-Anchored Silicone for the Degenerative Intervertebral Disc

PubMed Central

Riahanizad, S.

2017-01-01

The nucleus pulposus (NP) substitution by polymeric gel is one of the promising techniques for the repair of the degenerative intervertebral disc (IVD). Silicone gel is one of the potential candidates for a NP replacement material. Electrospun fiber anchorage to silicone disc, referred as ENAS disc, may not only improve the biomechanical performances of the gel but it can also improve restoration capability of the gel, which is unknown. This study successfully produced a novel process to anchor any size and shape of NP gel with electrospun fiber mesh. Viscoelastic properties of silicone and ENAS disc were measured using standard experimental techniques and compared with the native tissue properties. Ex vivo mechanical tests were conducted on ENAS disc-implanted rabbit tails to the compare the mechanical stability between intact and ENAS implanted spines. This study found that viscoelastic properties of ENAS disc are higher than silicone disc and comparable to the viscoelastic properties of human NP. The ex vivo studies found that the ENAS disc restore the mechanical functionality of rabbit tail spine, after discectomy of native NP and replacing the NP by ENAS disc. Therefore, the PCL ENF mesh anchoring technique to a NP implant can have clinical potential. PMID:29181144

The synergy of honokiol and fluconazole against clinical isolates of azole-resistant Candida albicans.

PubMed

Jin, J; Guo, N; Zhang, J; Ding, Y; Tang, X; Liang, J; Li, L; Deng, X; Yu, L

2010-09-01

To evaluate the interaction of fluconazole (FLC) and honokiol (HNK) in vitro and vivo against azole-resistant (azole-R) clinical isolates of Candida albicans. A checkerboard microdilution method was used to study the in vitro interaction of FLC and HNK in 24 azole-R clinical isolates of C. albicans. In vivo antifungal activity was performed to further analyse the interaction between FLC and HNK. In the in vitro study, synergism was observed in all 24 FLC-resistant strains tested as determined by fractional inhibitory concentration index (FICI), and in 22 strains by Delta E models. No antagonistic activity was observed in any of the strains tested. These positive interactions were also confirmed by using the time-killing test for the selected strain C. albicans YL371, which shows strong susceptible to the combination of HNK and FLC. In the in vivo study, the mice with candidiasis were treated successfully by a combination therapy of HNK with FLC, the results showed a decrease of the colony forming unit in infected and treated animals compared to the controls, at the conditions of the treatment used in this study. Synergistic activity of HNK and FLC against clinical isolates of FLC-resistant C. albicans was observed in vitro and in vivo. This report might provide a potential therapeutic method to overcome the problem of drug-resistance in C. albicans.

Development and evaluation of nanoparticles based on mPEG-PLA for controlled delivery of vinpocetine: in vitro and in vivo studies.

PubMed

Wang, Run; Xu, Yong

2017-02-01

The aim of present study was to develop VIN-loaded mPEG-PLA nanoparticle systems. The VIN mPEG-PLA nanoparticles were prepared using an emulsion solvent evaporation method, and studied their particle size, morphology, encapsulation efficiency and drug-loading coefficient. Moreover, the nanoparticles were evaluated on the drug release behaviors in vitro and bioavailability in vivo. The results show that the spherical nanoparticles obtained were negatively charged with a zeta potential of about -23.4 mV and characterized ∼110 nm with a narrow size distribution. The encapsulation efficiency and drug loading of prepared NPs were 76.4 ± 6.3 and 9.2 ± 2.2% (n=5), respectively. The in vitro release showed that the percent of accumulated dissolution of VIN NPs in phosphate-buffered saline 6.8 over 24 h was <80%, which was almost 100% of VIN in commercial injections. The in vivo study indicated that systemic absorption of VIN was significantly enhanced by incorporating into mPEG-PLA NPs compared with VIN injection (2.87-fold in AUC 0- t ). The results suggested that the form of VIN in mPEG-PLA NPs could enter the body circulation to perform sustained release in vitro and in vivo.

Fasudil and SOD packaged in peptide-studded-liposomes: Properties, pharmacokinetics and ex-vivo targeting to isolated perfused rat lungs.

PubMed

Gupta, Nilesh; Al-Saikhan, Fahad I; Patel, Brijeshkumar; Rashid, Jahidur; Ahsan, Fakhrul

2015-07-05

The present study investigated the feasibility of encapsulating two drugs, fasudil and superoxide dismutase (SOD), into liposomes for targeted and inhalational delivery to the pulmonary vasculature to treat pulmonary arterial hypertension (PAH). Nanosized liposomes were prepared by a thin-film formation and extrusion method, and the drugs were encapsulated by a modified freeze-thaw technique. The peptide CARSKNKDC (CAR), a pulmonary-specific targeting sequence, was conjugated on the surface of liposomes. Formulations were optimized for various physicochemical properties, tested for their ex-vivo and in-vivo drug absorption after intratracheal administration, and evaluated for short-term safety in healthy rats. The homogenous nanosized liposomes contained both SOD (~55% entrapment) and fasudil (~40% entrapment), and were stable at 4°C and after nebulization. Liposomes released the drugs in a controlled-release fashion. Compared with plain liposomes, CAR-liposomes increased the uptake by pulmonary endothelial and smooth muscle cells by ~2-fold. CAR-liposomes extended the biological half-lives of SOD and fasudil by ~3-fold. Ex-vivo studies demonstrated that CAR-liposomes were better retained in the lungs than plain liposomes. Bronchoalveolar lavage studies indicated the safety of peptide-equipped liposomes as pulmonary delivery carriers. Overall, this study demonstrates that CAR-liposomes may be used as inhalational carriers for SOD plus fasudil-based combination therapy for PAH. Published by Elsevier B.V.

Nanodiamonds for Medical Applications: Interaction with Blood in Vitro and in Vivo.

PubMed

Tsai, Lin-Wei; Lin, Yu-Chung; Perevedentseva, Elena; Lugovtsov, Andrei; Priezzhev, Alexander; Cheng, Chia-Liang

2016-07-12

Nanodiamonds (ND) have emerged to be a widely-discussed nanomaterial for their applications in biological studies and for medical diagnostics and treatment. The potentials have been successfully demonstrated in cellular and tissue models in vitro. For medical applications, further in vivo studies on various applications become important. One of the most challenging possibilities of ND biomedical application is controllable drug delivery and tracing. That usually assumes ND interaction with the blood system. In this work, we study ND interaction with rat blood and analyze how the ND surface modification and coating can optimize the ND interaction with the blood. It was found that adsorption of a low concentration of ND does not affect the oxygenation state of red blood cells (RBC). The obtained in vivo results are compared to the results of in vitro studies of nanodiamond interaction with rat and human blood and blood components, such as red blood cells and blood plasma. An in vivo animal model shows ND injected in blood attach to the RBC membrane and circulate with blood for more than 30 min; and ND do not stimulate an immune response by measurement of proinflammatory cytokine TNF-α with ND injected into mice via the caudal vein. The results further confirm nanodiamonds' safety in organisms, as well as the possibility of their application without complicating the blood's physiological conditions.

Nanodiamonds for Medical Applications: Interaction with Blood in Vitro and in Vivo

PubMed Central

Tsai, Lin-Wei; Lin, Yu-Chung; Perevedentseva, Elena; Lugovtsov, Andrei; Priezzhev, Alexander; Cheng, Chia-Liang

2016-01-01

Nanodiamonds (ND) have emerged to be a widely-discussed nanomaterial for their applications in biological studies and for medical diagnostics and treatment. The potentials have been successfully demonstrated in cellular and tissue models in vitro. For medical applications, further in vivo studies on various applications become important. One of the most challenging possibilities of ND biomedical application is controllable drug delivery and tracing. That usually assumes ND interaction with the blood system. In this work, we study ND interaction with rat blood and analyze how the ND surface modification and coating can optimize the ND interaction with the blood. It was found that adsorption of a low concentration of ND does not affect the oxygenation state of red blood cells (RBC). The obtained in vivo results are compared to the results of in vitro studies of nanodiamond interaction with rat and human blood and blood components, such as red blood cells and blood plasma. An in vivo animal model shows ND injected in blood attach to the RBC membrane and circulate with blood for more than 30 min; and ND do not stimulate an immune response by measurement of proinflammatory cytokine TNF-α with ND injected into mice via the caudal vein. The results further confirm nanodiamonds’ safety in organisms, as well as the possibility of their application without complicating the blood’s physiological conditions. PMID:27420044

Confocal laser endomicroscopy for in vivo diagnosis of Barrett's oesophagus and associated neoplasia: a pilot study conducted in a single Italian centre.

PubMed

Trovato, Cristina; Sonzogni, Angelica; Ravizza, Davide; Fiori, Giancarla; Tamayo, Darina; De Roberto, Giuseppe; de Leone, Annalisa; De Lisi, Stefania; Crosta, Cristiano

2013-05-01

Diagnosis and management of Barrett's oesophagus are controversial. Technical improvements in real-time recognition of intestinal metaplasia and neoplastic foci provide the chance for more effective target biopsies. Confocal laser endomicroscopy allows to analyze living cells during endoscopy. To assess the diagnostic accuracy, inter- and intra-observer variability of endomicroscopy for detecting in vivo neoplasia (dysplasia and/or early neoplasia) in Barrett's oesophagus. Prospective pilot study. Patients referred for known Barrett's oesophagus were screened. Endomicroscopy was carried out in a circular fashion, every 1-2 cm, on the whole columnar-lined distal oesophagus. Visible lesions, when present, were analyzed first. Targeted biopsies were taken. Confocal images were classified according to confocal Barrett classification. Endomicroscopic and histological findings were compared. Forty-eight out of 50 screened patients underwent endomicroscopy. Visible lesions were observed in 3 patients. In a per-biopsy analysis, Barrett's-oesophagus-associated neoplasia could be predicted with an accuracy of 98.1%. The agreement between endomicroscopic and histological results was substantial (κ=0.76). This study suggests that endomicroscopy can provide in vivo diagnosis of Barrett's oesophagus-associated neoplasia. Because it allows for the study of larger surface areas of the mucosa, endomicroscopy may lead to significant improvements in the in vivo screening and surveillance of Barrett's oesophagus. Copyright © 2013 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

In vivo contact kinematics and contact forces of the knee after total knee arthroplasty during dynamic weight-bearing activities.

PubMed

Varadarajan, Kartik M; Moynihan, Angela L; D'Lima, Darryl; Colwell, Clifford W; Li, Guoan

2008-07-19

Analysis of polyethylene component wear and implant loosening in total knee arthroplasty (TKA) requires precise knowledge of in vivo articular motion and loading conditions. This study presents a simultaneous in vivo measurement of tibiofemoral articular contact forces and contact kinematics in three TKA patients. These measurements were accomplished via a dual fluoroscopic imaging system and instrumented tibial implants, during dynamic single leg lunge and chair rising-sitting. The measured forces and contact locations were also used to determine mediolateral distribution of axial contact forces. Contact kinematics data showed a medial pivot during flexion of the knee, for all patients in the study. Average axial forces were higher for lunge compared to chair rising-sitting (224% vs. 187% body weight). In this study, we measured peak anteroposterior and mediolateral forces averaging 13.3% BW during lunge and 18.5% BW during chair rising-sitting. Mediolateral distributions of axial contact force were both patient and activity specific. All patients showed equitable medial-lateral loading during lunge but greater loads at the lateral compartment during chair rising-sitting. The results of this study may enable more accurate reproduction of in vivo loads and articular motion patterns in wear simulators and finite element models. This in turn may help advance our understanding of factors limiting longevity of TKA implants, such as aseptic loosening and polyethylene component wear, and enable improved TKA designs.

The Equine Antimicrobial Peptide eCATH1 Is Effective against the Facultative Intracellular Pathogen Rhodococcus equi in Mice

PubMed Central

Schlusselhuber, Margot; Torelli, Riccardo; Martini, Cecilia; Leippe, Matthias; Cattoir, Vincent; Leclercq, Roland; Laugier, Claire; Grötzinger, Joachim; Sanguinetti, Maurizio

2013-01-01

Rhodococcus equi, the causal agent of rhodococcosis, is a major pathogen of foals and is also responsible for severe infections in immunocompromised humans. Of great concern, strains resistant to currently used antibiotics have emerged. As the number of drugs that are efficient in vivo is limited because of the intracellular localization of the bacterium inside macrophages, new active but cell-permeant drugs will be needed in the near future. In the present study, we evaluated, by in vitro and ex vivo experiments, the ability of the alpha-helical equine antimicrobial peptide eCATH1 to kill intracellular bacterial cells. Moreover, the therapeutic potential of the peptide was assessed in experimental rhodococcosis induced in mice, while the in vivo toxicity was evaluated by behavioral and histopathological analysis. The study revealed that eCATH1 significantly reduced the number of bacteria inside macrophages. Furthermore, the bactericidal potential of the peptide was maintained in vivo at doses that appeared to have no visible deleterious effects for the mice even after 7 days of treatment. Indeed, daily subcutaneous injections of 1 mg/kg body weight of eCATH1 led to a significant reduction of the bacterial load in organs comparable to that obtained after treatment with 10 mg/kg body weight of rifampin. Interestingly, the combination of the peptide with rifampin showed a synergistic interaction in both ex vivo and in vivo experiments. These results emphasize the therapeutic potential that eCATH1 represents in the treatment of rhodococcosis. PMID:23817377

Qualichem In Vivo: A Tool for Assessing the Quality of In Vivo Studies and Its Application for Bisphenol A

PubMed Central

Maxim, Laura; van der Sluijs, Jeroen P.

2014-01-01

In regulatory toxicology, quality assessment of in vivo studies is a critical step for assessing chemical risks. It is crucial for preserving public health studies that are considered suitable for regulating chemicals are robust. Current procedures for conducting quality assessments in safety agencies are not structured, clear or consistent. This leaves room for criticism about lack of transparency, subjective influence and the potential for insufficient protection provided by resulting safety standards. We propose a tool called “Qualichem in vivo” that is designed to systematically and transparently assess the quality of in vivo studies used in chemical health risk assessment. We demonstrate its use here with 12 experts, using two controversial studies on Bisphenol A (BPA) that played an important role in BPA regulation in Europe. The results obtained with Qualichem contradict the quality assessments conducted by expert committees in safety agencies for both of these studies. Furthermore, they show that reliance on standardized guidelines to ensure scientific quality is only partially justified. Qualichem allows experts with different disciplinary backgrounds and professional experiences to express their individual and sometimes divergent views—an improvement over the current way of dealing with minority opinions. It provides a transparent framework for expressing an aggregated, multi-expert level of confidence in a study, and allows a simple graphical representation of how well the study integrates the best available scientific knowledge. Qualichem can be used to compare assessments of the same study by different health agencies, increasing transparency and trust in the work of expert committees. In addition, it may be used in systematic evaluation of in vivo studies submitted by industry in the dossiers that are required for compliance with the REACH Regulation. Qualichem provides a balanced, common framework for assessing the quality of studies that may or may not be following standardized guidelines. PMID:24489958

Development of a histologically validated segmentation protocol for the hippocampal body.

PubMed

Steve, Trevor A; Yasuda, Clarissa L; Coras, Roland; Lail, Mohjevan; Blumcke, Ingmar; Livy, Daniel J; Malykhin, Nikolai; Gross, Donald W

2017-08-15

Recent findings have demonstrated that hippocampal subfields can be selectively affected in different disease states, which has led to efforts to segment the human hippocampus with in vivo magnetic resonance imaging (MRI). However, no studies have examined the histological accuracy of subfield segmentation protocols. The presence of MRI-visible anatomical landmarks with known correspondence to histology represents a fundamental prerequisite for in vivo hippocampal subfield segmentation. In the present study, we aimed to: 1) develop a novel method for hippocampal body segmentation, based on two MRI-visible anatomical landmarks (stratum lacunosum moleculare [SLM] & dentate gyrus [DG]), and assess its accuracy in comparison to the gold standard direct histological measurements; 2) quantify the accuracy of two published segmentation strategies in comparison to the histological gold standard; and 3) apply the novel method to ex vivo MRI and correlate the results with histology. Ultra-high resolution ex vivo MRI was performed on six whole cadaveric hippocampal specimens, which were then divided into 22 blocks and histologically processed. The hippocampal bodies were segmented into subfields based on histological criteria and subfield boundaries and areas were directly measured. A novel method was developed using mean percentage of the total SLM distance to define subfield boundaries. Boundary distances and subfield areas on histology were then determined using the novel method and compared to the gold standard histological measurements. The novel method was then used to determine ex vivo MRI measures of subfield boundaries and areas, which were compared to histological measurements. For direct histological measurements, the mean percentages of total SLM distance were: Subiculum/CA1 = 9.7%, CA1/CA2 = 78.4%, CA2/CA3 = 97.5%. When applied to histology, the novel method provided accurate measures for CA1/CA2 (ICC = 0.93) and CA2/CA3 (ICC = 0.97) boundaries, but not for the Subiculum/CA1 (ICC = -0.04) boundary. Accuracy was poorer using previous techniques for CA1/CA2 (maximum ICC = 0.85) and CA2/CA3 (maximum ICC = 0.88), with the previously reported techniques also performing poorly in defining the Subiculum/CA1 boundary (maximum ICC = 0.00). Ex vivo MRI measurements using the novel method were linearly related to direct measurements of SLM length (r 2 = 0.58), CA1/CA2 boundary (r 2 = 0.39) and CA2/CA3 boundary (r 2 = 0.47), but not for Subiculum/CA1 boundary (r 2 = 0.01). Subfield areas measured with the novel method on histology and ex vivo MRI were linearly related to gold standard histological measures for CA1, CA2, and CA3/CA4/DG. In this initial proof of concept study, we used ex vivo MRI and histology of cadaveric hippocampi to develop a novel segmentation protocol for the hippocampal body. The novel method utilized two anatomical landmarks, SLM & DG, and provided accurate measurements of CA1, CA2, and CA3/CA4/DG subfields in comparison to the gold standard histological measurements. The relationships demonstrated between histology and ex vivo MRI supports the potential feasibility of applying this method to in vivo MRI studies. Copyright © 2017. Published by Elsevier Inc.

Tissue inhibitor of matrix metalloproteinases-1 loaded poly(lactic-co-glycolic acid) nanoparticles for delivery across the blood–brain barrier

PubMed Central

Chaturvedi, Mayank; Molino, Yves; Sreedhar, Bojja; Khrestchatisky, Michel; Kaczmarek, Leszek

2014-01-01

Aim The aim of this study was to develop poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) for delivery of a protein – tissue inhibitor of matrix metalloproteinases 1 (TIMP-1) – across the blood–brain barrier (BBB) to inhibit deleterious matrix metalloproteinases (MMPs). Materials and methods The NPs were formulated by multiple-emulsion solvent-evaporation, and for enhancing BBB penetration, they were coated with polysorbate 80 (Ps80). We compared Ps80-coated and uncoated NPs for their toxicity, binding, and BBB penetration on primary rat brain capillary endothelial cell cultures and the rat brain endothelial 4 cell line. These studies were followed by in vivo studies for brain delivery of these NPs. Results Results showed that neither Ps80-coated nor uncoated NPs caused significant opening of the BBB, and essentially they were nontoxic. NPs without Ps80 coating had more binding to endothelial cells compared to Ps80-coated NPs. Penetration studies showed that TIMP-1 NPs + Ps80 had 11.21%±1.35% penetration, whereas TIMP-1 alone and TIMP-1 NPs without Ps80 coating did not cross the endothelial monolayer. In vivo studies indicated BBB penetration of intravenously injected TIMP-1 NPs + Ps80. Conclusion The study demonstrated that Ps80 coating of NPs does not cause significant toxic effects to endothelial cells and that it can be used to enhance the delivery of protein across endothelial cell barriers, both in vitro and in vivo. PMID:24531257

Quantitative MR Imaging of Hepatic Steatosis: Validation in Ex Vivo Human Livers

PubMed Central

Bannas, Peter; Kramer, Harald; Hernando, Diego; Agni, Rashmi; Cunningham, Ashley M.; Mandal, Rakesh; Motosugi, Utaroh; Sharma, Samir D.; del Rio, Alejandro Munoz; Fernandez, Luis; Reeder, Scott B.

2015-01-01

Emerging magnetic resonance imaging (MRI) biomarkers of hepatic steatosis have demonstrated tremendous promise for accurate quantification of hepatic triglyceride concentration. These methods quantify the “proton density fat-fraction” (PDFF), which reflects the concentration of triglycerides in tissue. Previous in vivo studies have compared MRI-PDFF with histologic steatosis grading for assessment of hepatic steatosis. However, the correlation of MRI-PDFF with the underlying hepatic triglyceride content remained unknown. The aim of this ex vivo study was to validate the accuracy of MRI-PDFF as an imaging biomarker of hepatic steatosis. Using ex vivo human livers, we compared MRI-PDFF with magnetic resonance spectroscopy-PDFF (MRS-PDFF), biochemical triglyceride extraction and histology as three independent reference standards. A secondary aim was to compare the precision of MRI-PDFF relative to biopsy for the quantification of hepatic steatosis. MRI-PDFF was prospectively performed at 1.5T in 13 explanted human livers. We performed co-localized paired evaluation of liver fat content in all nine Couinaud segments using single-voxel MRS-PDFF (n=117), tissue wedges for biochemical triglyceride extraction (n=117), and five core biopsies performed in each segment for histologic grading (n=585). Accuracy of MRI-PDFF was assessed through linear regression with MRS-PDFF, triglyceride extraction and histology. Intra-observer agreement, inter-observer agreement and repeatability of MRI-PDFF and histologic grading were assessed through Bland-Altman analyses. MRI-PDFF showed an excellent correlation with MRS-PDFF (r=0.984; CI: 0.978–0.989) and strong correlation with histology (r=0.850; CI: 0.791–0.894) and triglyceride extraction (r=0.871; CI: 0.818–0.909). Intra-observer agreement, inter-observer agreement and repeatability showed a significantly smaller variance for MRI-PDFF than for histologic steatosis grading (all p<0.001). Conclusion MRI-PDFF is an accurate, precise and reader-independent non-invasive imaging biomarker of liver triglyceride content, capable of steatosis quantification over the entire liver. PMID:26224591

In vivo and in vitro kinetics of ethylene oxide metabolism in rats and mice.

PubMed

Brown, C D; Wong, B A; Fennell, T R

1996-01-01

Ethylene oxide (EO) is a direct-acting mutagen and animal carcinogen used as an industrial intermediate and sterilant with a high potential for human exposure. Kinetics of EO metabolism in rodents can be used to develop human EO dosimetry models. This study examined the kinetics of EO metabolism in vivo and in vitro in male and female F-344 rats and B6C3F1 mice. In vivo studies measured blood and tissue EO levels during and 2-20 min following whole-body inhalation exposure (4 hr, 100 or 330 ppm EO). At 100 ppm EO, the half-life of elimination (t1/2) in rats was 13.8 +/- 0.3 (mean +/- SD) and 10.8 +/- 2.4 min for males and females, respectively, compared to a t1/2 in mice of 3.12 +/- 0.2 and 2.4 +/- 0.2 min in males and females, respectively. On exposure to 330 ppm EO, the t1/2 in mice increased approx twofold, while no change in t1/2 was observed in rats. In vitro kinetic parameters (Vmax and KM) of EO metabolism were determined using tissue cytosol and microsomes. EO metabolism in vitro occurred primarily via cytosolic glutathione S-transferase-mediated EO-GSH conjugation (cGST-EO), with highest activity in the liver. Liver cGST-EO activity (Vmax) was 258 +/- 86.9 and 287 +/- 49.0 nmol/mg protein/min (mean +/- SD) in male and female mice, respectively, compared to 52.7 +/- 10.8 and 29.3 +/- 4.9 in male and female rats, respectively. In rats, but not mice, there was a statistically significant (p < 0.05) gender difference in the Vmax for liver cGST. The KM for liver cGST-EO was approximately 10 mM in both species. The higher Vmax values observed in mice are consistent with the more rapid elimination of EO observed for this species in vivo compared to rats.

Effect of embryo source and recipient progesterone environment on embryo development in cattle.

PubMed

Lonergan, P; Woods, A; Fair, T; Carter, F; Rizos, D; Ward, F; Quinn, K; Evans, A

2007-01-01

The aim of the present study was to examine the effect of embryo source (in vivo v. in vitro) and the progesterone environment into which it was transferred on Day 7 on embryo survival and size on Day 13. Day 7 blastocysts were produced either in vivo using superovulation, artificial insemination and non-surgical embryo recovery or in vitro using in vitro maturation, fertilisation and culture. In order to produce animals with divergent progesterone concentrations, following synchronisation recipients were either superovulated (High progesterone; n = 10) or not (Control progesterone; n = 10). Ten blastocysts, produced either in vivo or in vitro, were transferred to each recipient on Day 7. Both groups were killed on Day 13. The mean progesterone concentration from Day 7 to Day 13 (the period when the embryos were in the uterus) in the High and Control progesterone recipients was 36.32 +/- 1.28 and 10.30 +/- 0.51 ng mL(-1), respectively. Of the in vivo embryos transferred, the overall recovery rate at Day 13 was 64%, which was higher (P < 0.001) than that of 20% for the in vitro embryos transferred. The mean area of embryos recovered from High progesterone recipients was 3.86 +/- 0.45 mm(2) (n = 28) compared with 1.66 +/- 0.38 mm(2) (n = 24) for embryos recovered from Control progesterone recipients (P < 0.001). Similarly, the origin of the embryo used for transfer affected embryo size on Day 13. In summary, the recovery rate of blastocysts was higher for in vivo- than in vitro-derived embryos. Blastocyst size was approximately 2.3-fold greater in recipients with high compared with normal progesterone. The present study lends strong support to the hypothesis that an earlier rise in progesterone after conception stimulates blastocyst growth and the development of competent embryos.

Coregistration of Preoperative MRI with Ex Vivo Mesorectal Pathology Specimens to Spatially Map Post-treatment Changes in Rectal Cancer Onto In Vivo Imaging: Preliminary Findings.

PubMed

Antunes, Jacob; Viswanath, Satish; Brady, Justin T; Crawshaw, Benjamin; Ros, Pablo; Steele, Scott; Delaney, Conor P; Paspulati, Raj; Willis, Joseph; Madabhushi, Anant

2018-07-01

The objective of this study was to develop and quantitatively evaluate a radiology-pathology fusion method for spatially mapping tissue regions corresponding to different chemoradiation therapy-related effects from surgically excised whole-mount rectal cancer histopathology onto preoperative magnetic resonance imaging (MRI). This study included six subjects with rectal cancer treated with chemoradiation therapy who were then imaged with a 3-T T2-weighted MRI sequence, before undergoing mesorectal excision surgery. Excised rectal specimens were sectioned, stained, and digitized as two-dimensional (2D) whole-mount slides. Annotations of residual disease, ulceration, fibrosis, muscularis propria, mucosa, fat, inflammation, and pools of mucin were made by an expert pathologist on digitized slide images. An expert radiologist and pathologist jointly established corresponding 2D sections between MRI and pathology images, as well as identified a total of 10 corresponding landmarks per case (based on visually similar structures) on both modalities (five for driving registration and five for evaluating alignment). We spatially fused the in vivo MRI and ex vivo pathology images using landmark-based registration. This allowed us to spatially map detailed annotations from 2D pathology slides onto corresponding 2D MRI sections. Quantitative assessment of coregistered pathology and MRI sections revealed excellent structural alignment, with an overall deviation of 1.50 ± 0.63 mm across five expert-selected anatomic landmarks (in-plane misalignment of two to three pixels at 0.67- to 1.00-mm spatial resolution). Moreover, the T2-weighted intensity distributions were distinctly different when comparing fibrotic tissue to perirectal fat (as expected), but showed a marked overlap when comparing fibrotic tissue and residual rectal cancer. Our fusion methodology enabled successful and accurate localization of post-treatment effects on in vivo MRI. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

In vivo and in vitro performance of a China-made hemodialysis machine: a multi-center prospective controlled study.

PubMed

Wang, Yong; Chen, Xiang-Mei; Cai, Guang-Yan; Li, Wen-Ge; Zhang, Ai-Hua; Hao, Li-Rong; Shi, Ming; Wang, Rong; Jiang, Hong-Li; Luo, Hui-Min; Zhang, Dong; Sun, Xue-Feng

2017-08-02

To evaluate the in vivo and in vitro performance of a China-made dialysis machine (SWS-4000). This was a multi-center prospective controlled study consisting of both long-term in vitro evaluations and cross-over in vivo tests in 132 patients. The China-made SWS-4000 dialysis machine was compared with a German-made dialysis machine (Fresenius 4008) with regard to Kt/V values, URR values, and dialysis-related adverse reactions in patients on maintenance hemodialysis, as well as the ultrafiltration rate, the concentration of electrolytes in the proportioned dialysate, the rate of heparin injection, the flow rate of the blood pump, and the rate of malfunction. The Kt/V and URR values at the 1st and 4th weeks of dialysis as well as the incidence of adverse effects did not differ between the two groups in cross-over in vivo tests (P > 0.05). There were no significant differences between the two groups in the error values of the ultrafiltration rate, the rate of heparin injection or the concentrations of electrolytes in the proportioned dialysate at different time points under different parameter settings. At weeks 2 and 24, with the flow rate of the blood pump set at 300 mL/min, the actual error of the SWS-4000 dialysis machine was significantly higher than that of the Fresenius 4008 dialysis machine (P < 0.05), but there was no significant difference at other time points or under other settings (P > 0.05). The malfunction rate was higher in the SWS-4000 group than in the Fresenius 4008 group (P < 0.05). The in vivo performance of the SWS-4000 dialysis machine is roughly comparable to that of the Fresenius 4008 dialysis machine; however, the malfunction rate of the former is higher than that of the latter in in vitro tests. The stability and long-term accuracy of the SWS-4000 dialysis machine remain to be improved.

A Phase 1 trial to assess the safety, acceptability, pharmacokinetics and pharmacodynamics of a novel dapivirine vaginal film

PubMed Central

Bunge, Authors: Katherine E.; Dezzutti, Charlene S.; Rohan, Lisa C.; Hendrix, Craig W.; Marzinke, Mark A.; Richardson-Harman, Nicola; Moncla, Bernard J.; Devlin, Brid; Meyn, Leslie A.; M.L.Spiegel, Hans; Hillier, Sharon L.

2016-01-01

Background Films may deliver antiretroviral drugs efficiently to mucosal tissues. In this first in-human trial of a vaginal film for delivering the non-nucleoside reverse transcriptase inhibitor dapivirine, safety, pharmacokinetics, and pharmacodynamics of film and gel formulations were compared to placebo. Methods 61 healthy HIV negative women were randomized to daily dapivirine (0.05%) or placebo gel, or dapivirine (1.25mg) or placebo film for seven days. The proportion of participants experiencing Grade 2 and higher adverse events related to study product were compared. Plasma dapivirine concentrations were quantified. Paired cervical and vaginal tissue biopsies obtained ∼2 hours following the last dose were measured for tissue drug concentration and exposed to HIV in an ex vivo challenge assay. Results Two Grade 2 related AEs occurred in the placebo film group. Women randomized to gel and film products had 4 log10 higher of dapivirine in cervical and vaginal tissues than plasma. While gel and film users had comparable plasma dapivirine concentrations, tissue concentrations of dapivirine were 3 to 5 times higher in the gel users when compared to film users. HIV replication in the ex vivo challenge assay was significantly reduced in vaginal tissues from women randomized to dapivirine film or gel; furthermore, tissue drug concentrations were highly correlated with HIV protection. Women rated the film more comfortable with less leakage, but found it more difficult to insert than gel. Discussion Both film and gel delivered dapivirine at concentrations sufficient to block HIV ex vivo. This proof of concept study suggests film formulations for microbicides merit further investigation. PMID:26565716