Small RNA analysis in Petunia hybrida identifies unusual tissue-specific expression patterns of conserved miRNAs and of a 24mer RNA

PubMed Central

Tedder, Philip; Zubko, Elena; Westhead, David R.; Meyer, Peter

2009-01-01

Two pools of small RNAs were cloned from inflorescences of Petunia hybrida using a 5′-ligation dependent and a 5′-ligation independent approach. The two libraries were integrated into a public website that allows the screening of individual sequences against 359,769 unique clones. The library contains 15 clones with 100% identity and 53 clones with one mismatch to miRNAs described for other plant species. For two conserved miRNAs, miR159 and miR390, we find clear differences in tissue-specific distribution, compared with other species. This shows that evolutionary conservation of miRNA sequences does not necessarily include a conservation of the miRNA expression profile. Almost 60% of all clones in the database are 24-nucleotide clones. In accordance with the role of 24mers in marking repetitive regions, we find them distributed across retroviral and transposable element sequences but other 24mers map to promoter regions and to different transcript regions. For one target region we observe tissue-specific variation of matching 24mers, which demonstrates that, as for 21mers, 24mer concentrations are not necessarily identical in different tissues. Asymmetric distribution of a putative novel miRNA in the two libraries suggests that the cloning method can be selective for the representation of certain small RNAs in a collection. PMID:19369427

Introducing nuclei scatterer patterns into histology based intravascular ultrasound simulation framework

NASA Astrophysics Data System (ADS)

Kraft, Silvan; Karamalis, Athanasios; Sheet, Debdoot; Drecoll, Enken; Rummeny, Ernst J.; Navab, Nassir; Noël, Peter B.; Katouzian, Amin

2013-03-01

Medical ultrasonic grayscale images are formed from acoustic waves following their interactions with distributed scatterers within tissues media. For accurate simulation of acoustic wave propagation, a reliable model describing unknown parameters associated with tissues scatterers such as distribution, size and acoustic properties is essential. In this work, we introduce a novel approach defining ultrasonic scatterers by incorporating a distribution of cellular nuclei patterns in biological tissues to simulate ultrasonic response of atherosclerotic tissues in intravascular ultrasound (IVUS). For this reason, a virtual phantom is generated through manual labeling of different tissue types (fibrotic, lipidic and calcified) on histology sections. Acoustic properties of each tissue type are defined by assuming that the ultrasound signal is primarily backscattered by the nuclei of the organic cells within the intima and media of the vessel wall. This resulting virtual phantom is subsequently used to simulate ultrasonic wave propagation through the tissue medium computed using finite difference estimation. Subsequently B-mode images for a specific histological section are processed from the simulated radiofrequency (RF) data and compared with the original IVUS of the same tissue section. Real IVUS RF signals for these histological sections were obtained using a single-element mechanically rotating 40MHz transducer. Evaluation is performed by trained reviewers subjectively assessing both simulated and real B-mode IVUS images. Our simulation platform provides a high image quality with a very promising correlation to the original IVUS images. This will facilitate to better understand progression of such a chronic disease from micro-level and its integration into cardiovascular disease-specific models.

WE-DE-201-12: Thermal and Dosimetric Properties of a Ferrite-Based Thermo-Brachytherapy Seed

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

Warrell, G; Shvydka, D; Parsai, E I

Purpose: The novel thermo-brachytherapy (TB) seed provides a simple means of adding hyperthermia to LDR prostate permanent implant brachytherapy. The high blood perfusion rate (BPR) within the prostate motivates the use of the ferrite and conductive outer layer design for the seed cores. We describe the results of computational analyses of the thermal properties of this ferrite-based TB seed in modelled patient-specific anatomy, as well as studies of the interseed and scatter (ISA) effect. Methods: The anatomies (including the thermophysical properties of the main tissue types) and seed distributions of 6 prostate patients who had been treated with LDR brachytherapymore » seeds were modelled in the finite element analysis software COMSOL, using ferrite-based TB and additional hyperthermia-only (HT-only) seeds. The resulting temperature distributions were compared to those computed for patient-specific seed distributions, but in uniform anatomy with a constant blood perfusion rate. The ISA effect was quantified in the Monte Carlo software package MCNP5. Results: Compared with temperature distributions calculated in modelled uniform tissue, temperature distributions in the patient-specific anatomy were higher and more heterogeneous. Moreover, the maximum temperature to the rectal wall was typically ∼1 °C greater for patient-specific anatomy than for uniform anatomy. The ISA effect of the TB and HT-only seeds caused a reduction in D90 similar to that found for previously-investigated NiCu-based seeds, but of a slightly smaller magnitude. Conclusion: The differences between temperature distributions computed for uniform and patient-specific anatomy for ferrite-based seeds are significant enough that heterogeneous anatomy should be considered. Both types of modelling indicate that ferrite-based seeds provide sufficiently high and uniform hyperthermia to the prostate, without excessively heating surrounding tissues. The ISA effect of these seeds is slightly less than that for the previously-presented NiCu-based seeds.« less

Widespread Non-Hematopoietic Tissue Distribution by Transplanted Human Progenitor Cells with High Aldehyde Dehydrogenase Activity

PubMed Central

Hess, David A.; Craft, Timothy P.; Wirthlin, Louisa; Hohm, Sarah; Zhou, Ping; Eades, William C.; Creer, Michael H.; Sands, Mark S.; Nolta, Jan A.

2011-01-01

Transplanted adult progenitor cells distribute to peripheral organs and can promote endogenous cellular repair in damaged tissues. However, development of cell-based regenerative therapies has been hindered by the lack of pre-clinical models to efficiently assess multiple organ distribution and difficulty defining human cells with regenerative function. After transplantation into beta-glucuronidase (GUSB)-deficient NOD/SCID/MPSVII mice, we characterized the distribution of lineage depleted human umbilical cord blood-derived cells purified by selection using high aldehyde dehydrogenase activity (ALDH) with CD133 co-expression. ALDHhi or ALDHhiCD133+ cells produced robust hematopoietic reconstitution, and variable levels of tissue distribution in multiple organs. GUSB+ donor cells that co-expressed human (HLA-A,B,C) and hematopoietic (CD45+) cell surface markers were the primary cell phenotype found adjacent to the vascular beds of several tissues, including islet and ductal regions of mouse pancreata. In contrast, variable phenotypes were detected in the chimeric liver, with HLA+/CD45+ cells demonstrating robust GUSB expression adjacent to blood vessels, and CD45−/HLA− cells with diluted GUSB expression predominant in the liver parenchyma. However, true non-hematopoietic human (HLA+/CD45−) cells were rarely detected in other peripheral tissues, suggesting that these GUSB+/HLA−/CD45− cells in the liver were a result of downregulated human surface marker expression in vivo, not widespread seeding of non-hematopoietic cells. However, relying solely on continued expression of cell surface markers, as employed in traditional xenotransplantation models, may underestimate true tissue distribution. ALDH-expressing progenitor cells demonstrated widespread and tissue-specific distribution of variable cellular phenotypes, indicating that these adult progenitor cells should be explored in transplantation models of tissue damage. PMID:18055447

Pharmacokinetics and tissue distribution of psammaplin A, a novel anticancer agent, in mice.

PubMed

Kim, Hak Jae; Kim, Tae Hwan; Seo, Won Sik; Yoo, Sun Dong; Kim, Il Han; Joo, Sang Hoon; Shin, Soyoung; Park, Eun-Seok; Ma, Eun Sook; Shin, Beom Soo

2012-10-01

This study reports the pharmacokinetics and tissue distribution of a novel histone deacetylase and DNA methyltransferase inhibitor, psammaplin A (PsA), in mice. PsA concentrations were determined by a validated LC-MS/MS assay method (LLOQ 2 ng/mL). Following intravenous injection at a dose of 10 mg/kg in mice, PsA was rapidly eliminated, with the average half-life (t(1/2, λn)) of 9.9 ± 1.4 min and the systemic clearance (CL(s)) of 925.1 ± 570.1 mL/min. The in vitro stability of PsA was determined in different tissue homogenates. The average degradation t(1/2) of PsA in blood, liver, kidney and lung was found relatively short (≤ 12.8 min). Concerning the in vivo tissue distribution characteristics, PsA was found to be highly distributed to lung tissues, with the lung-to-serum partition coefficients (K(p)) ranging from 49.9 to 60.2. In contrast, PsA concentrations in other tissues were either comparable with or less than serum concentrations. The high and specific lung targeting characteristics indicates that PsA has the potential to be developed as a lung cancer treatment agent.

Analysis of Mass Averaged Tissue Doses in CAM, CAF, MAX, and FAX

NASA Technical Reports Server (NTRS)

Slaba, Tony C.; Qualls, Garry D.; Clowdsley, Martha S.; Blattnig, Steve R.; Simonsen, Lisa C.; Walker, Steven A.; Singleterry, Robert C.

2009-01-01

To estimate astronaut health risk due to space radiation, one must have the ability to calculate exposure-related quantities averaged over specific organs and tissue types. In this study, we first examine the anatomical properties of the Computerized Anatomical Man (CAM), Computerized Anatomical Female (CAF), Male Adult voXel (MAX), and Female Adult voXel (FAX) models by comparing the masses of various tissues to the reference values specified by the International Commission on Radiological Protection (ICRP). Major discrepancies are found between the CAM and CAF tissue masses and the ICRP reference data for almost all of the tissues. We next examine the distribution of target points used with the deterministic transport code HZETRN to compute mass averaged exposure quantities. A numerical algorithm is used to generate multiple point distributions for many of the effective dose tissues identified in CAM, CAF, MAX, and FAX. It is concluded that the previously published CAM and CAF point distributions were under-sampled and that the set of point distributions presented here should be adequate for future studies involving CAM, CAF, MAX, or FAX. It is concluded that MAX and FAX are more accurate than CAM and CAF for space radiation analyses.

A family of tissue-specific resistin-like molecules

PubMed Central

Steppan, Claire M.; Brown, Elizabeth J.; Wright, Christopher M.; Bhat, Savitha; Banerjee, Ronadip R.; Dai, Charlotte Y.; Enders, Gregory H.; Silberg, Debra G.; Wen, Xiaoming; Wu, Gary D.; Lazar, Mitchell A.

2001-01-01

We have identified a family of resistin-like molecules (RELMs) in rodents and humans. Resistin is a hormone produced by fat cells. RELMα is a secreted protein that has a restricted tissue distribution with highest levels in adipose tissue. Another family member, RELMβ, is a secreted protein expressed only in the gastrointestinal tract, particularly the colon, in both mouse and human. RELMβ gene expression is highest in proliferative epithelial cells and is markedly increased in tumors, suggesting a role in intestinal proliferation. Resistin and the RELMs share a cysteine composition and other signature features. Thus, the RELMs together with resistin comprise a class of tissue-specific signaling molecules. PMID:11209052

A family of tissue-specific resistin-like molecules.

PubMed

Steppan, C M; Brown, E J; Wright, C M; Bhat, S; Banerjee, R R; Dai, C Y; Enders, G H; Silberg, D G; Wen, X; Wu, G D; Lazar, M A

2001-01-16

We have identified a family of resistin-like molecules (RELMs) in rodents and humans. Resistin is a hormone produced by fat cells. RELMalpha is a secreted protein that has a restricted tissue distribution with highest levels in adipose tissue. Another family member, RELMbeta, is a secreted protein expressed only in the gastrointestinal tract, particularly the colon, in both mouse and human. RELMbeta gene expression is highest in proliferative epithelial cells and is markedly increased in tumors, suggesting a role in intestinal proliferation. Resistin and the RELMs share a cysteine composition and other signature features. Thus, the RELMs together with resistin comprise a class of tissue-specific signaling molecules.

Temperature distribution analysis of tissue water vaporization during microwave ablation: experiments and simulations.

PubMed

Ai, Haiming; Wu, Shuicai; Gao, Hongjian; Zhao, Lei; Yang, Chunlan; Zeng, Yi

2012-01-01

The temperature distribution in the region near a microwave antenna is a critical factor that affects the entire temperature field during microwave ablation of tissue. It is challenging to predict this distribution precisely, because the temperature in the near-antenna region varies greatly. The effects of water vaporisation and subsequent tissue carbonisation in an ex vivo porcine liver were therefore studied experimentally and in simulations. The enthalpy and high-temperature specific absorption rate (SAR) of liver tissues were calculated and incorporated into the simulation process. The accuracy of predictions for near-field temperatures in our simulations has reached the level where the average maximum error is less than 5°C. In addition, a modified thermal model that accounts for water vaporisation and the change in the SAR distribution pattern is proposed and validated with experiment. The results from this study may be useful in the clinical practice of microwave ablation and can be applied to predict the temperature field in surgical planning.

Cell-size distribution in epithelial tissue formation and homeostasis

PubMed Central

Primo, Luca; Celani, Antonio

2017-01-01

How cell growth and proliferation are orchestrated in living tissues to achieve a given biological function is a central problem in biology. During development, tissue regeneration and homeostasis, cell proliferation must be coordinated by spatial cues in order for cells to attain the correct size and shape. Biological tissues also feature a notable homogeneity of cell size, which, in specific cases, represents a physiological need. Here, we study the temporal evolution of the cell-size distribution by applying the theory of kinetic fragmentation to tissue development and homeostasis. Our theory predicts self-similar probability density function (PDF) of cell size and explains how division times and redistribution ensure cell size homogeneity across the tissue. Theoretical predictions and numerical simulations of confluent non-homeostatic tissue cultures show that cell size distribution is self-similar. Our experimental data confirm predictions and reveal that, as assumed in the theory, cell division times scale like a power-law of the cell size. We find that in homeostatic conditions there is a stationary distribution with lognormal tails, consistently with our experimental data. Our theoretical predictions and numerical simulations show that the shape of the PDF depends on how the space inherited by apoptotic cells is redistributed and that apoptotic cell rates might also depend on size. PMID:28330988

Cell-size distribution in epithelial tissue formation and homeostasis.

PubMed

Puliafito, Alberto; Primo, Luca; Celani, Antonio

2017-03-01

How cell growth and proliferation are orchestrated in living tissues to achieve a given biological function is a central problem in biology. During development, tissue regeneration and homeostasis, cell proliferation must be coordinated by spatial cues in order for cells to attain the correct size and shape. Biological tissues also feature a notable homogeneity of cell size, which, in specific cases, represents a physiological need. Here, we study the temporal evolution of the cell-size distribution by applying the theory of kinetic fragmentation to tissue development and homeostasis. Our theory predicts self-similar probability density function (PDF) of cell size and explains how division times and redistribution ensure cell size homogeneity across the tissue. Theoretical predictions and numerical simulations of confluent non-homeostatic tissue cultures show that cell size distribution is self-similar. Our experimental data confirm predictions and reveal that, as assumed in the theory, cell division times scale like a power-law of the cell size. We find that in homeostatic conditions there is a stationary distribution with lognormal tails, consistently with our experimental data. Our theoretical predictions and numerical simulations show that the shape of the PDF depends on how the space inherited by apoptotic cells is redistributed and that apoptotic cell rates might also depend on size. © 2017 The Author(s).

Tissue reservoirs of antiviral T cell immunity in persistent human CMV infection

PubMed Central

Gordon, Claire L.; Thome, Joseph J.C.; Igarashi, Suzu

2017-01-01

T cell responses to viruses are initiated and maintained in tissue sites; however, knowledge of human antiviral T cells is largely derived from blood. Cytomegalovirus (CMV) persists in most humans, requires T cell immunity to control, yet tissue immune responses remain undefined. Here, we investigated human CMV-specific T cells, virus persistence and CMV-associated T cell homeostasis in blood, lymphoid, mucosal and secretory tissues of 44 CMV seropositive and 28 seronegative donors. CMV-specific T cells were maintained in distinct distribution patterns, highest in blood, bone marrow (BM), or lymph nodes (LN), with the frequency and function in blood distinct from tissues. CMV genomes were detected predominantly in lung and also in spleen, BM, blood and LN. High frequencies of activated CMV-specific T cells were found in blood and BM samples with low virus detection, whereas in lung, CMV-specific T cells were present along with detectable virus. In LNs, CMV-specific T cells exhibited quiescent phenotypes independent of virus. Overall, T cell differentiation was enhanced in sites of viral persistence with age. Together, our results suggest tissue T cell reservoirs for CMV control shaped by both viral and tissue-intrinsic factors, with global effects on homeostasis of tissue T cells over the lifespan. PMID:28130404

Tissue reservoirs of antiviral T cell immunity in persistent human CMV infection.

PubMed

Gordon, Claire L; Miron, Michelle; Thome, Joseph J C; Matsuoka, Nobuhide; Weiner, Joshua; Rak, Michael A; Igarashi, Suzu; Granot, Tomer; Lerner, Harvey; Goodrum, Felicia; Farber, Donna L

2017-03-06

T cell responses to viruses are initiated and maintained in tissue sites; however, knowledge of human antiviral T cells is largely derived from blood. Cytomegalovirus (CMV) persists in most humans, requires T cell immunity to control, yet tissue immune responses remain undefined. Here, we investigated human CMV-specific T cells, virus persistence and CMV-associated T cell homeostasis in blood, lymphoid, mucosal and secretory tissues of 44 CMV seropositive and 28 seronegative donors. CMV-specific T cells were maintained in distinct distribution patterns, highest in blood, bone marrow (BM), or lymph nodes (LN), with the frequency and function in blood distinct from tissues. CMV genomes were detected predominantly in lung and also in spleen, BM, blood and LN. High frequencies of activated CMV-specific T cells were found in blood and BM samples with low virus detection, whereas in lung, CMV-specific T cells were present along with detectable virus. In LNs, CMV-specific T cells exhibited quiescent phenotypes independent of virus. Overall, T cell differentiation was enhanced in sites of viral persistence with age. Together, our results suggest tissue T cell reservoirs for CMV control shaped by both viral and tissue-intrinsic factors, with global effects on homeostasis of tissue T cells over the lifespan. @Gordon et al.

Combinatorial evaluation of in vivo distribution of polyanhydride particle-based platforms for vaccine delivery

PubMed Central

Petersen, Latrisha K; Huntimer, Lucas; Walz, Katharine; Ramer-Tait, Amanda; Wannemuehler, Michael J; Narasimhan, Balaji

2013-01-01

Several challenges are associated with current vaccine strategies, including repeated immunizations, poor patient compliance, and limited approved routes for delivery, which may hinder induction of protective immunity. Thus, there is a need for new vaccine adjuvants capable of multi-route administration and prolonged antigen release at the site of administration by providing a depot within tissue. In this work, we designed a combinatorial platform to investigate the in vivo distribution, depot effect, and localized persistence of polyanhydride nanoparticles as a function of nanoparticle chemistry and administration route. Our observations indicated that the route of administration differentially affected tissue residence times. All nanoparticles rapidly dispersed when delivered intranasally but provided a depot when administered parenterally. When amphiphilic and hydrophobic nanoparticles were administered intranasally, they persisted within lung tissue. These results provide insights into the chemistry- and route-dependent distribution and tissue-specific association of polyanhydride nanoparticle-based vaccine adjuvants. PMID:23818778

Combinatorial evaluation of in vivo distribution of polyanhydride particle-based platforms for vaccine delivery.

PubMed

Petersen, Latrisha K; Huntimer, Lucas; Walz, Katharine; Ramer-Tait, Amanda; Wannemuehler, Michael J; Narasimhan, Balaji

2013-01-01

Several challenges are associated with current vaccine strategies, including repeated immunizations, poor patient compliance, and limited approved routes for delivery, which may hinder induction of protective immunity. Thus, there is a need for new vaccine adjuvants capable of multi-route administration and prolonged antigen release at the site of administration by providing a depot within tissue. In this work, we designed a combinatorial platform to investigate the in vivo distribution, depot effect, and localized persistence of polyanhydride nanoparticles as a function of nanoparticle chemistry and administration route. Our observations indicated that the route of administration differentially affected tissue residence times. All nanoparticles rapidly dispersed when delivered intranasally but provided a depot when administered parenterally. When amphiphilic and hydrophobic nanoparticles were administered intranasally, they persisted within lung tissue. These results provide insights into the chemistry- and route-dependent distribution and tissue-specific association of polyanhydride nanoparticle-based vaccine adjuvants.

Zooming In on Plant Hormone Analysis: Tissue- and Cell-Specific Approaches.

PubMed

Novák, Ondřej; Napier, Richard; Ljung, Karin

2017-04-28

Plant hormones are a group of naturally occurring, low-abundance organic compounds that influence physiological processes in plants. Our knowledge of the distribution profiles of phytohormones in plant organs, tissues, and cells is still incomplete, but advances in mass spectrometry have enabled significant progress in tissue- and cell-type-specific analyses of phytohormones over the last decade. Mass spectrometry is able to simultaneously identify and quantify hormones and their related substances. Biosensors, on the other hand, offer continuous monitoring; can visualize local distributions and real-time quantification; and, in the case of genetically encoded biosensors, are noninvasive. Thus, biosensors offer additional, complementary technologies for determining temporal and spatial changes in phytohormone concentrations. In this review, we focus on recent advances in mass spectrometry-based quantification, describe monitoring systems based on biosensors, and discuss validations of the various methods before looking ahead at future developments for both approaches.

Development of a Novel Tissue Specific Aromatase Activity Regulation Therapeutic Method

DTIC Science & Technology

2009-09-01

Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT Estrogen is essential for normal growth and development of the female ...the ovaries and other tissues of the body using an enzyme called aromatase. Once women have reached menopause, the ovaries no longer produce estrogen...Introduction Estrogen is essential for normal growth and development of the female reproductive system, including breast tissue, and lifetime

Autoradiographic and biochemical observations on the distribution of non-steroid anti-inflammatory drugs.

PubMed

Rainsford, K D; Schweitzer, A; Brune, K

1981-04-01

A comparison has been made of the distribution of some new radioactively-labelled non-steroid anti-inflammatory (NSAI) drugs or pro-drugs with their respective progenitors and/or standard acidic NSAI drugs (i.e. aspirin, indomethacin and phenylbutazone), using whole body autoradiography and scintillation counting. The object of this study was to establish if the distribution of these new NSAI drugs may contribute to changes in their side-, or therapeutic effects compared with the older drugs. All the NSAI drugs accumulated in those tissues wherein the principle therapeutic and side-effects are manifest. The accumulation in inflamed tissues occurs regardless of the structural type of NSAI drugs, i.e. with specific accumulation occurring in this tissue of the acidic drugs or their acidic metabolites. New aspects of the distribution of the acetyl moiety of aspirin are reported which may be significant in relation to the side-effects induced by this drug.

Epigenetic regulation of depot-specific gene expression in adipose tissue.

PubMed

Gehrke, Sandra; Brueckner, Bodo; Schepky, Andreas; Klein, Johannes; Iwen, Alexander; Bosch, Thomas C G; Wenck, Horst; Winnefeld, Marc; Hagemann, Sabine

2013-01-01

In humans, adipose tissue is distributed in subcutaneous abdominal and subcutaneous gluteal depots that comprise a variety of functional differences. Whereas energy storage in gluteal adipose tissue has been shown to mediate a protective effect, an increase of abdominal adipose tissue is associated with metabolic disorders. However, the molecular basis of depot-specific characteristics is not completely understood yet. Using array-based analyses of transcription profiles, we identified a specific set of genes that was differentially expressed between subcutaneous abdominal and gluteal adipose tissue. To investigate the role of epigenetic regulation in depot-specific gene expression, we additionally analyzed genome-wide DNA methylation patterns in abdominal and gluteal depots. By combining both data sets, we identified a highly significant set of depot-specifically expressed genes that appear to be epigenetically regulated. Interestingly, the majority of these genes form part of the homeobox gene family. Moreover, genes involved in fatty acid metabolism were also differentially expressed. Therefore we suppose that changes in gene expression profiles might account for depot-specific differences in lipid composition. Indeed, triglycerides and fatty acids of abdominal adipose tissue were more saturated compared to triglycerides and fatty acids in gluteal adipose tissue. Taken together, our results uncover clear differences between abdominal and gluteal adipose tissue on the gene expression and DNA methylation level as well as in fatty acid composition. Therefore, a detailed molecular characterization of adipose tissue depots will be essential to develop new treatment strategies for metabolic syndrome associated complications.

Probing the Differential Tissue Distribution and Bioaccumulation Behavior of Per- and Polyfluoroalkyl Substances of Varying Chain-Lengths, Isomeric Structures and Functional Groups in Crucian Carp.

PubMed

Shi, Yali; Vestergren, Robin; Nost, Therese Haugdahl; Zhou, Zhen; Cai, Yaqi

2018-04-17

Understanding the bioaccumulation mechanisms of per- and polyfluoroalkyl substances (PFASs) across different chain-lengths, isomers and functional groups represents a monumental scientific challenge with implications for chemical regulation. Here, we investigate how the differential tissue distribution and bioaccumulation behavior of 25 PFASs in crucian carp from two field sites impacted by point sources can provide information about the processes governing uptake, distribution and elimination of PFASs. Median tissue/blood ratios (TBRs) were consistently <1 for all PFASs and tissues except bile which displayed a distinct distribution pattern and enrichment of several perfluoroalkyl sulfonic acids. Transformation of concentration data into relative body burdens (RBBs) demonstrated that blood, gonads, and muscle together accounted for >90% of the amount of PFASs in the organism. Principal component analyses of TBRs and RBBs showed that the functional group was a relatively more important predictor of internal distribution than chain-length for PFASs. Whole body bioaccumulation factors (BAFs) for short-chain PFASs deviated from the positive relationship with hydrophobicity observed for longer-chain homologues. Overall, our results suggest that TBR, RBB, and BAF patterns were most consistent with protein binding mechanisms although partitioning to phospholipids may contribute to the accumulation of long-chain PFASs in specific tissues.

Tissue distribution of pretomanid in rat brain via mass spectrometry imaging.

PubMed

Shobo, Adeola; Bratkowska, Dominika; Baijnath, Sooraj; Naiker, Suhashni; Somboro, Anou M; Bester, Linda A; Singh, Sanil D; Naicker, Tricia; Kruger, Hendrik G; Govender, Thavendran

2016-01-01

1. Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) combines the sensitivity and selectivity of mass spectrometry with spatial analysis to provide a new dimension for histological analyses of the distribution of drugs in tissue. Pretomanid is a pro-drug belonging to a class of antibiotics known as nitroimidizoles, which have been proven to be active under hypoxic conditions and to the best of our knowledge there have been no studies investigating the distribution and localisation of this class of compounds in the brain using MALDI MSI. 2. Herein, we report on the distribution of pretomanid in the healthy rat brain after intraperitoneal administration (20 mg/kg) using MALDI MSI. Our findings showed that the drug localises in specific compartments of the rat brain viz. the corpus callosum, a dense network of neurons connecting left and right cerebral hemispheres. 3. This study proves that MALDI MSI technique has great potential for mapping the pretomanid distribution in uninfected tissue samples, without the need for molecular labelling.

Raman microspectroscopy of Hematoporphyrins. Imaging of the noncancerous and the cancerous human breast tissues with photosensitizers

NASA Astrophysics Data System (ADS)

Brozek-Pluska, B.; Kopec, M.

2016-12-01

Raman microspectroscopy combined with fluorescence were used to study the distribution of Hematoporphyrin (Hp) in noncancerous and cancerous breast tissues. The results demonstrate the ability of Raman spectroscopy to distinguish between noncancerous and cancerous human breast tissue and to identify differences in the distribution and photodegradation of Hematoporphyrin, which is a photosensitizer in photodynamic therapy (PDT), photodynamic diagnosis (PDD) and photoimmunotherapy (PIT) of cancer. Presented results show that Hematoporphyrin level in the noncancerous breast tissue is lower compared to the cancerous one. We have proved also that the Raman intensity of lipids and proteins doesn't change dramatically after laser light irradiation, which indicates that the PDT treatment destroys preferably cancer cells, in which the photosensitizer is accumulated. The specific subcellular localization of photosensitizer for breast tissues samples soaked with Hematoporphyrin was not observed.

Computed Tomography-Based Biomarker for Longitudinal Assessment of Disease Burden in Pulmonary Tuberculosis.

PubMed

Gordaliza, P M; Muñoz-Barrutia, A; Via, L E; Sharpe, S; Desco, M; Vaquero, J J

2018-05-29

Computed tomography (CT) images enable capturing specific manifestations of tuberculosis (TB) that are undetectable using common diagnostic tests, which suffer from limited specificity. In this study, we aimed to automatically quantify the burden of Mycobacterium tuberculosis (Mtb) using biomarkers extracted from x-ray CT images. Nine macaques were aerosol-infected with Mtb and treated with various antibiotic cocktails. Chest CT scans were acquired in all animals at specific times independently of disease progression. First, a fully automatic segmentation of the healthy lungs from the acquired chest CT volumes was performed and air-like structures were extracted. Next, unsegmented pulmonary regions corresponding to damaged parenchymal tissue and TB lesions were included. CT biomarkers were extracted by classification of the probability distribution of the intensity of the segmented images into three tissue types: (1) Healthy tissue, parenchyma free from infection; (2) soft diseased tissue, and (3) hard diseased tissue. The probability distribution of tissue intensities was assumed to follow a Gaussian mixture model. The thresholds identifying each region were automatically computed using an expectation-maximization algorithm. The estimated longitudinal course of TB infection shows that subjects that have followed the same antibiotic treatment present a similar response (relative change in the diseased volume) with respect to baseline. More interestingly, the correlation between the diseased volume (soft tissue + hard tissue), which was manually delineated by an expert, and the automatically extracted volume with the proposed method was very strong (R 2  ≈ 0.8). We present a methodology that is suitable for automatic extraction of a radiological biomarker from CT images for TB disease burden. The method could be used to describe the longitudinal evolution of Mtb infection in a clinical trial devoted to the design of new drugs.

Measured body composition and geometrical data of four ``virtual family'' members for thermoregulatory modeling

NASA Astrophysics Data System (ADS)

Xu, Xiaojiang; Rioux, Timothy P.; MacLeod, Tynan; Patel, Tejash; Rome, Maxwell N.; Potter, Adam W.

2017-03-01

The purpose of this paper is to develop a database of tissue composition, distribution, volume, surface area, and skin thickness from anatomically correct human models, the virtual family. These models were based on high-resolution magnetic resonance imaging (MRI) of human volunteers, including two adults (male and female) and two children (boy and girl). In the segmented image dataset, each voxel is associated with a label which refers to a tissue type that occupies up that specific cubic millimeter of the body. The tissue volume was calculated from the number of the voxels with the same label. Volumes of 24 organs in body and volumes of 7 tissues in 10 specific body regions were calculated. Surface area was calculated from the collection of voxels that are touching the exterior air. Skin thicknesses were estimated from its volume and surface area. The differences between the calculated and original masses were about 3 % or less for tissues or organs that are important to thermoregulatory modeling, e.g., muscle, skin, and fat. This accurate database of body tissue distributions and geometry is essential for the development of human thermoregulatory models. Data derived from medical imaging provide new effective tools to enhance thermal physiology research and gain deeper insight into the mechanisms of how the human body maintains heat balance.

Is it time for a new classification of mast cells? What do we know about mast cell heterogeneity?

PubMed

Frossi, Barbara; Mion, Francesca; Sibilano, Riccardo; Danelli, Luca; Pucillo, Carlo E M

2018-03-01

Mast cells (MCs) are derived from committed precursors that leave the hematopoietic tissue, migrate in the blood, and colonize peripheral tissues where they terminally differentiate under microenvironment stimuli. They are distributed in almost all vascularized tissues where they act both as immune effectors and housekeeping cells, contributing to tissue homeostasis. Historically, MCs were classified into 2 subtypes, according to tryptic enzymes expression. However, MCs display a striking heterogeneity that reflects a complex interplay between different microenvironmental signals delivered by various tissues, and a differentiation program that decides their identity. Moreover, tissue-specific MCs show a trained memory, which contributes to shape their function in a specific microenvironment. In this review, we summarize the current state of our understanding of MC heterogeneity that reflects their different tissue experiences. We describe the discovery of unique cell molecules that can be used to distinguish specific MC subsets in vivo, and discuss how the improved ability to recognize these subsets provided new insights into the biology of MCs. These recent advances will be helpful for the understanding of the specific role of individual MC subsets in the control of tissue homeostasis, and in the regulation of pathological conditions such as infection, autoimmunity, and cancer. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Microdialysis as an Important Technique in Systems Pharmacology-a Historical and Methodological Review.

PubMed

Hammarlund-Udenaes, Margareta

2017-09-01

Microdialysis has contributed with very important knowledge to the understanding of target-specific concentrations and their relationship to pharmacodynamic effects from a systems pharmacology perspective, aiding in the global understanding of drug effects. This review focuses on the historical development of microdialysis as a method to quantify the pharmacologically very important unbound tissue concentrations and of recent findings relating to modeling microdialysis data to extrapolate from rodents to humans, understanding distribution of drugs in different tissues and disease conditions. Quantitative microdialysis developed very rapidly during the early 1990s. Method development was in focus in the early years including development of quantitative microdialysis, to be able to estimate true extracellular concentrations. Microdialysis has significantly contributed to the understanding of active transport at the blood-brain barrier and in other organs. Examples are presented where microdialysis together with modeling has increased the knowledge on tissue distribution between species, in overweight patients and in tumors, and in metabolite contribution to drug effects. More integrated metabolomic studies are still sparse within the microdialysis field, although a great potential for tissue and disease-specific measurements is evident.

Pretranslational Suppression of an Insulin-Responsive Glucose Transporter in Rats with Diabetes Mellitus

NASA Astrophysics Data System (ADS)

Garvey, W. Timothy; Huecksteadt, Thomas P.; Birnbaum, Morris J.

1989-07-01

A prominent feature of diabetes mellitus is the inability of insulin to appropriately increase the transport of glucose into target tissues. The contributions of different glucose transport proteins to insulin resistance in rats with streptozotocin-induced diabetes was evaluated. A glucose transporter messenger RNA and its cognate protein that are exclusively expressed in muscle and adipose tissue were specifically depleted in diabetic animals, and these effects were reversed after insulin therapy; a different glucose transporter and its messenger RNA that exhibit a less restricted tissue distribution were not specifically modulated in this way. Depletion of the muscle- and adipose-specific glucose transporter species correlates with and may account for the major portion of cellular insulin resistance in diabetes in these animals.

Heat transfer analysis of skin during thermal therapy using thermal wave equation.

PubMed

Kashcooli, Meisam; Salimpour, Mohammad Reza; Shirani, Ebrahim

2017-02-01

Specifying exact geometry of vessel network and its effect on temperature distribution in living tissues is one of the most complicated problems of the bioheat field. In this paper, the effects of blood vessels on temperature distribution in a skin tissue subjected to various thermal therapy conditions are investigated. Present model consists of counter-current multilevel vessel network embedded in a three-dimensional triple-layered skin structure. Branching angles of vessels are calculated using the physiological principle of minimum work. Length and diameter ratios are specified using length doubling rule and Cube law, respectively. By solving continuity, momentum and energy equations for blood flow and Pennes and modified Pennes bioheat equations for the tissue, temperature distributions in the tissue are measured. Effects of considering modified Pennes bioheat equation are investigated, comprehensively. It is also observed that blood has an impressive role in temperature distribution of the tissue, especially at high temperatures. The effects of different parameters such as boundary conditions, relaxation time, thermal properties of skin, metabolism and pulse heat flux on temperature distribution are investigated. Tremendous effect of boundary condition type at the lower boundary is noted. It seems that neither insulation nor constant temperature at this boundary can completely describe the real physical phenomena. It is expected that real temperature at the lower levels is somewhat between two predicted values. The effect of temperature on the thermal properties of skin tissue is considered. It is shown that considering temperature dependent values for thermal conductivity is important in the temperature distribution estimation of skin tissue; however, the effect of temperature dependent values for specific heat capacity is negligible. It is seen that considering modified Pennes equation in processes with high heat flux during low times is significant. Copyright © 2016 Elsevier Ltd. All rights reserved.

Angiocrine functions of organ-specific endothelial cells

PubMed Central

Rafii, Shahin; Butler, Jason M; Ding, Bi-Sen

2016-01-01

Preface Endothelial cells lining blood vessel capillaries are not just passive conduits for delivering blood. Tissue-specific endothelium establish specialized vascular niches that deploy specific sets of growth factors, known as angiocrine factors, which actively participate in inducing, specifying, patterning, and guiding organ regeneration and maintaining homeostasis and metabolism. Angiocrine factors upregulated in response to injury orchestrates self-renewal and differentiation of tissue-specific repopulating resident stem and progenitor cells into functional organs. Uncovering the precise mechanisms whereby physiological-levels of angiocrine factors are spatially and temporally produced, and distributed by organotypic endothelium to repopulating cells, will lay the foundation for driving organ repair without scarring. PMID:26791722

Sparse Feature Selection Identifies H2A.Z as a Novel, Pattern-Specific Biomarker for Asymmetrically Self-Renewing Distributed Stem Cells

PubMed Central

Huh, Yang Hoon; Noh, Minsoo; Burden, Frank R.; Chen, Jennifer C.; Winkler, David A.; Sherley, James L.

2015-01-01

There is a long-standing unmet clinical need for biomarkers with high specificity for distributed stem cells (DSCs) in tissues, or for use in diagnostic and therapeutic cell preparations (e.g., bone marrow). Although DSCs are essential for tissue maintenance and repair, accurate determination of their numbers for medical applications has been problematic. Previous searches for biomarkers expressed specifically in DSCs were hampered by difficulty obtaining pure DSCs and by the challenges in mining complex molecular expression data. To identify DSC such useful and specific biomarkers, we combined a novel sparse feature selection method with combinatorial molecular expression data focused on asymmetric self-renewal, a conspicuous property of DSCs. The analysis identified reduced expression of the histone H2A variant H2A.Z as a superior molecular discriminator for DSC asymmetric self-renewal. Subsequent molecular expression studies showed H2A.Z to be a novel “pattern-specific biomarker” for asymmetrically self-renewing cells with sufficient specificity to count asymmetrically self-renewing DSCs in vitro and potentially in situ. PMID:25636161

Determination of pharmacological levels of harmane, harmine and harmaline in mammalian brain tissue, cerebrospinal fluid and plasma by high-performance liquid chromatography with fluorimetric detection.

PubMed

Moncrieff, J

1989-11-24

Increased blood aldehyde levels, as occur in alcohol intoxication, could lead to the formation of beta-carbolines such as harmane by condensation with indoleamines. Endogenous beta-carbolines, therefore, should occur in specific brain areas where indoleamine concentrations are high, whilst exogenous beta-carbolines should exhibit an even distribution. The author presents direct and sensitive methods for assaying the beta-carbolines harmane, harmine and harmaline in brain tissue, cerebrospinal fluid and plasma at picogram sample concentrations using reversed-phase high-performance liquid chromatography with fluorimetric detection and minimal sample preparation. Using these assay methods, it was found that the distribution of beta-carbolines from a source exogenous to the brain results in a relatively even distribution within the brain tissue.

Characteristics of microRNAs enriched in specific cell types and primary tissue types in solid organs.

PubMed

Kriegel, Alison J; Liu, Yong; Liu, Pengyuan; Baker, Maria Angeles; Hodges, Matthew R; Hua, Xing; Liang, Mingyu

2013-12-01

Knowledge of miRNA expression and function in specific cell types in solid organs is limited because of difficulty in obtaining appropriate specimens. We used laser capture microdissection to obtain nine tissue regions from rats, including the nucleus of the solitary tract, hypoglossal motor nucleus, ventral respiratory column/pre-Bötzinger complex, and midline raphe nucleus from the brain stem, myocardium and coronary artery from the heart, and glomerulus, proximal convoluted tubule, and medullary thick ascending limb from the kidney. Each tissue region consists of or is enriched for a specific cell type. Differential patterns of miRNA expression obtained by deep sequencing of minute amounts of laser-captured cells were highly consistent with data obtained from real-time PCR analysis. miRNA expression patterns correctly clustered the specimens by tissue regions and then by primary tissue types (neural, muscular, or epithelial). The aggregate difference in miRNA profiles between tissue regions that contained the same primary tissue type was as large as one-half of the aggregate difference between primary tissue types. miRNAs differentially expressed between primary tissue types are more likely to be abundant miRNAs, while miRNAs differentially expressed between tissue regions containing the same primary tissue type were distributed evenly across the abundance spectrum. The tissue type-enriched miRNAs were more likely to target genes enriched for specific functional categories compared with either cell type-enriched miRNAs or randomly selected miRNAs. These data indicate that the role of miRNAs in determining characteristics of primary tissue types may be different than their role in regulating cell type-specific functions in solid organs.

Mueller-matrix mapping of biological tissues in differential diagnosis of optical anisotropy mechanisms of protein networks

NASA Astrophysics Data System (ADS)

Ushenko, V. A.; Sidor, M. I.; Marchuk, Yu F.; Pashkovskaya, N. V.; Andreichuk, D. R.

2015-03-01

We report a model of Mueller-matrix description of optical anisotropy of protein networks in biological tissues with allowance for the linear birefringence and dichroism. The model is used to construct the reconstruction algorithms of coordinate distributions of phase shifts and the linear dichroism coefficient. In the statistical analysis of such distributions, we have found the objective criteria of differentiation between benign and malignant tissues of the female reproductive system. From the standpoint of evidence-based medicine, we have determined the operating characteristics (sensitivity, specificity and accuracy) of the Mueller-matrix reconstruction method of optical anisotropy parameters and demonstrated its effectiveness in the differentiation of benign and malignant tumours.

Azimuth-invariant mueller-matrix differentiation of the optical anisotropy of biological tissues

NASA Astrophysics Data System (ADS)

Ushenko, V. A.; Sidor, M. I.; Marchuk, Yu. F.; Pashkovskaya, N. V.; Andreichuk, D. R.

2014-07-01

A Mueller-matrix model is proposed for analysis of the optical anisotropy of protein networks of optically thin nondepolarizing layers of biological tissues with allowance for birefringence and dichroism. The model is used to construct algorithms for reconstruction of coordinate distributions of phase shifts and coefficient of linear dichroism. Objective criteria for differentiation of benign and malignant tissues of female genitals are formulated in the framework of the statistical analysis of such distributions. Approaches of evidence-based medicine are used to determine the working characteristics (sensitivity, specificity, and accuracy) of the Mueller-matrix method for the reconstruction of the parameters of optical anisotropy and show its efficiency in the differentiation of benign and malignant tumors.

Raman microspectroscopy of Hematoporphyrins. Imaging of the noncancerous and the cancerous human breast tissues with photosensitizers.

PubMed

Brozek-Pluska, B; Kopec, M

2016-12-05

Raman microspectroscopy combined with fluorescence were used to study the distribution of Hematoporphyrin (Hp) in noncancerous and cancerous breast tissues. The results demonstrate the ability of Raman spectroscopy to distinguish between noncancerous and cancerous human breast tissue and to identify differences in the distribution and photodegradation of Hematoporphyrin, which is a photosensitizer in photodynamic therapy (PDT), photodynamic diagnosis (PDD) and photoimmunotherapy (PIT) of cancer. Presented results show that Hematoporphyrin level in the noncancerous breast tissue is lower compared to the cancerous one. We have proved also that the Raman intensity of lipids and proteins doesn't change dramatically after laser light irradiation, which indicates that the PDT treatment destroys preferably cancer cells, in which the photosensitizer is accumulated. The specific subcellular localization of photosensitizer for breast tissues samples soaked with Hematoporphyrin was not observed. Copyright © 2016 Elsevier B.V. All rights reserved.

Collagen in Human Tissues: Structure, Function, and Biomedical Implications from a Tissue Engineering Perspective

NASA Astrophysics Data System (ADS)

Balasubramanian, Preethi; Prabhakaran, Molamma P.; Sireesha, Merum; Ramakrishna, Seeram

The extracellular matrix is a complex biological structure encoded with various proteins, among which the collagen family is the most significant and abundant of all, contributing 30-35% of the whole-body protein. "Collagen" is a generic term for proteins that forms a triple-helical structure with three polypeptide chains, and around 29 types of collagen have been identified up to now. Although most of the members of the collagen family form such supramolecular structures, extensive diversity exists between each type of collagen. The diversity is not only based on the molecular assembly and supramolecular structures of collagen types but is also observed within its tissue distribution, function, and pathology. Collagens possess complex hierarchical structures and are present in various forms such as collagen fibrils (1.5-3.5 nm wide), collagen fibers (50-70 nm wide), and collagen bundles (150-250 nm wide), with distinct properties characteristic of each tissue providing elasticity to skin, softness of the cartilage, stiffness of the bone and tendon, transparency of the cornea, opaqueness of the sclera, etc. There exists an exclusive relation between the structural features of collagen in human tissues (such as the collagen composition, collagen fibril length and diameter, collagen distribution, and collagen fiber orientation) and its tissue-specific mechanical properties. In bone, a transverse collagen fiber orientation prevails in regions of higher compressive stress whereas longitudinally oriented collagen fibers correlate to higher tensile stress. The immense versatility of collagen compels a thorough understanding of the collagen types and this review discusses the major types of collagen found in different human tissues, highlighting their tissue-specific uniqueness based on their structure and mechanical function. The changes in collagen during a specific tissue damage or injury are discussed further, focusing on the many tissue engineering applications for which collagen scaffolds are currently being applied.

PhosphoregDB: The tissue and sub-cellular distribution of mammalian protein kinases and phosphatases

PubMed Central

Forrest, Alistair RR; Taylor, Darrin F; Fink, J Lynn; Gongora, M Milena; Flegg, Cameron; Teasdale, Rohan D; Suzuki, Harukazu; Kanamori, Mutsumi; Kai, Chikatoshi; Hayashizaki, Yoshihide; Grimmond, Sean M

2006-01-01

Background Protein kinases and protein phosphatases are the fundamental components of phosphorylation dependent protein regulatory systems. We have created a database for the protein kinase-like and phosphatase-like loci of mouse that integrates protein sequence, interaction, classification and pathway information with the results of a systematic screen of their sub-cellular localization and tissue specific expression data mined from the GNF tissue atlas of mouse. Results The database lets users query where a specific kinase or phosphatase is expressed at both the tissue and sub-cellular levels. Similarly the interface allows the user to query by tissue, pathway or sub-cellular localization, to reveal which components are co-expressed or co-localized. A review of their expression reveals 30% of these components are detected in all tissues tested while 70% show some level of tissue restriction. Hierarchical clustering of the expression data reveals that expression of these genes can be used to separate the samples into tissues of related lineage, including 3 larger clusters of nervous tissue, developing embryo and cells of the immune system. By overlaying the expression, sub-cellular localization and classification data we examine correlations between class, specificity and tissue restriction and show that tyrosine kinases are more generally expressed in fewer tissues than serine/threonine kinases. Conclusion Together these data demonstrate that cell type specific systems exist to regulate protein phosphorylation and that for accurate modelling and for determination of enzyme substrate relationships the co-location of components needs to be considered. PMID:16504016

The aluminium content of breast tissue taken from women with breast cancer.

PubMed

House, Emily; Polwart, Anthony; Darbre, Philippa; Barr, Lester; Metaxas, George; Exley, Christopher

2013-10-01

The aetiology of breast cancer is multifactorial. While there are known genetic predispositions to the disease it is probable that environmental factors are also involved. Recent research has demonstrated a regionally specific distribution of aluminium in breast tissue mastectomies while other work has suggested mechanisms whereby breast tissue aluminium might contribute towards the aetiology of breast cancer. We have looked to develop microwave digestion combined with a new form of graphite furnace atomic absorption spectrometry as a precise, accurate and reproducible method for the measurement of aluminium in breast tissue biopsies. We have used this method to test the thesis that there is a regional distribution of aluminium across the breast in women with breast cancer. Microwave digestion of whole breast tissue samples resulted in clear homogenous digests perfectly suitable for the determination of aluminium by graphite furnace atomic absorption spectrometry. The instrument detection limit for the method was 0.48 μg/L. Method blanks were used to estimate background levels of contamination of 14.80 μg/L. The mean concentration of aluminium across all tissues was 0.39 μg Al/g tissue dry wt. There were no statistically significant regionally specific differences in the content of aluminium. We have developed a robust method for the precise and accurate measurement of aluminium in human breast tissue. There are very few such data currently available in the scientific literature and they will add substantially to our understanding of any putative role of aluminium in breast cancer. While we did not observe any statistically significant differences in aluminium content across the breast it has to be emphasised that herein we measured whole breast tissue and not defatted tissue where such a distribution was previously noted. We are very confident that the method developed herein could now be used to provide accurate and reproducible data on the aluminium content in defatted tissue and oil from such tissues and thereby contribute towards our knowledge on aluminium and any role in breast cancer. Copyright © 2013 Elsevier GmbH. All rights reserved.

The establishment of a national tissue bank for inflammatory bowel disease research in Canada.

PubMed

Collins, Stephen M; McHugh, Kevin; Croitoru, Ken; Howorth, Michael

2003-02-01

The Crohn's and Colitis Foundation of Canada (CCFC) has established a national bank for tissue, serum and blood from patients with inflammatory bowel disease (IBD). Investigators from across the country submit material to the bank together with clinical data. Investigators may access their own patient information from the bank for their own study purposes, but the distribution of tissue is restricted to specific CCFC-funded projects. Currently, tissues are being collected from newly diagnosed, untreated IBD patients to support a recent initiative aimed at characterizing microbes in colonic and ileal biopsies from such patients. In the future, criteria for the submission of tissue will be tailored to specific research questions. This bank is believed to be the first national bank of its kind dedicated to research in Crohn's disease and ulcerative colitis

Image-based metrology of porous tissue engineering scaffolds

NASA Astrophysics Data System (ADS)

Rajagopalan, Srinivasan; Robb, Richard A.

2006-03-01

Tissue engineering is an interdisciplinary effort aimed at the repair and regeneration of biological tissues through the application and control of cells, porous scaffolds and growth factors. The regeneration of specific tissues guided by tissue analogous substrates is dependent on diverse scaffold architectural indices that can be derived quantitatively from the microCT and microMR images of the scaffolds. However, the randomness of pore-solid distributions in conventional stochastic scaffolds presents unique computational challenges. As a result, image-based characterization of scaffolds has been predominantly qualitative. In this paper, we discuss quantitative image-based techniques that can be used to compute the metrological indices of porous tissue engineering scaffolds. While bulk averaged quantities such as porosity and surface are derived directly from the optimal pore-solid delineations, the spatially distributed geometric indices are derived from the medial axis representations of the pore network. The computational framework proposed (to the best of our knowledge for the first time in tissue engineering) in this paper might have profound implications towards unraveling the symbiotic structure-function relationship of porous tissue engineering scaffolds.

The Role of Mechanical Variance and Spatial Clustering on the Likelihood of Tumor Incidence and Growth

NASA Astrophysics Data System (ADS)

Mirzakhel, Zibah

When considering factors that contribute to cancer progression, modifications to both the biological and mechanical pathways play significant roles. However, less attention is placed on how the mechanical pathways can specifically contribute to cancerous behavior. Experimental studies have found that malignant cells are significantly softer than healthy, normal cells. In a tissue environment where healthy or malignant cells exist, a distribution of cell stiffness values is observed, with the mean values used to differentiate between these two populations. Rather than focus on the mean values, emphasis will be placed on the distribution, where instances of soft and stiff cells exist in the healthy tissue environment. Since cell deformability is a trait associated with cancer, the question arises as to whether the mechanical variation observed in healthy tissue cell stiffness distributions can influence any instances of tumor growth. To approach this, a 3D discrete model of cells is used, able to monitor and predict the behavior of individual cells while determining any instances of tumor growth in a healthy tissue. In addition to the mechanical variance, the spatial arrangement of cells will also be modeled, as cell interaction could further implicate any incidences of tumor-like malignant populations within the tissue. Results have shown that the likelihood of tumor incidence is driven by both by the increases in the mechanical variation in the distributions as well as larger clustering of cells that are mechanically similar, quantified primarily through higher proliferation rates of tumor-like soft cells. This can be observed though prominent negative shifts in the mean of the distribution, as it begins to transition and show instances of earlystage tumor growth. The model reveals the impact that both the mechanical variation and spatial arrangement of cells has on tumor progression, suggesting the use of these parameters as potential novel biomarkers. With a patient-specific approach in mind, the model may be applied for early-stage cancer detection, useful to establish a timeline on tumor progression.

Multiscale Modeling of Antibody Drug Conjugates: Connecting tissue and cellular distribution to whole animal pharmacokinetics and potential implications for efficacy

PubMed Central

Cilliers, Cornelius; Guo, Hans; Liao, Jianshan; Christodolu, Nikolas; Thurber, Greg M.

2016-01-01

Antibody drug conjugates exhibit complex pharmacokinetics due to their combination of macromolecular and small molecule properties. These issues range from systemic concerns, such as deconjugation of the small molecule drug during the long antibody circulation time or rapid clearance from non-specific interactions, to local tumor tissue heterogeneity, cell bystander effects, and endosomal escape. Mathematical models can be used to study the impact of these processes on overall distribution in an efficient manner, and several types of models have been used to analyze varying aspects of antibody distribution including physiologically based pharmacokinetic (PBPK) models and tissue-level simulations. However, these processes are quantitative in nature and cannot be handled qualitatively in isolation. For example, free antibody from deconjugation of the small molecule will impact the distribution of conjugated antibodies within the tumor. To incorporate these effects into a unified framework, we have coupled the systemic and organ-level distribution of a PBPK model with the tissue-level detail of a distributed parameter tumor model. We used this mathematical model to analyze new experimental results on the distribution of the clinical antibody drug conjugate Kadcyla in HER2 positive mouse xenografts. This model is able to capture the impact of the drug antibody ratio (DAR) on tumor penetration, the net result of drug deconjugation, and the effect of using unconjugated antibody to drive ADC penetration deeper into the tumor tissue. This modeling approach will provide quantitative and mechanistic support to experimental studies trying to parse the impact of multiple mechanisms of action for these complex drugs. PMID:27287046

Root anatomy and element distribution vary between two Salix caprea isolates with different Cd accumulation capacities

PubMed Central

Vaculík, Marek; Konlechner, Cornelia; Langer, Ingrid; Adlassnig, Wolfram; Puschenreiter, Markus; Lux, Alexander; Hauser, Marie-Theres

2012-01-01

The understanding of the influence of toxic elements on root anatomy and element distribution is still limited. This study describes anatomical responses, metal accumulation and element distribution of rooted cuttings of Salix caprea after exposure to Cd and/or Zn. Differences in the development of apoplastic barriers and tissue organization in roots between two distinct S. caprea isolates with divergent Cd uptake and accumulation capacities in leaves might reflect an adaptive predisposition based on different natural origins. Energy-dispersive X-ray spectroscopy (EDX) revealed that Cd and Zn interfered with the distribution of elements in a tissue- and isolate-specific manner. Zinc, Ca, Mg, Na and Si were enriched in the peripheral bark, K and S in the phloem and Cd in both vascular tissues. Si levels were lower in the superior Cd translocator. Since the cuttings originated from stocks isolated from polluted and unpolluted sites we probably uncovered different strategies against toxic elements. PMID:22325439

Specific binding of TES-23 antibody to tumour vascular endothelium in mice, rats and human cancer tissue: a novel drug carrier for cancer targeting therapy

PubMed Central

Tsunoda, S; Ohizumi, I; Matsui, J; Koizumi, K; Wakai, Y; Makimoto, H; Tsutsumi, Y; Utoguchi, N; Taniguchi, K; Saito, H; Harada, N; Ohsugi, Y; Mayumi, T

1999-01-01

The tissue distribution of anti-tumour vascular endothelium monoclonal antibody (TES-23) produced by immunizing with plasma membrane vesicles from isolated rat tumour-derived endothelial cells (TECs) was assessed in various tumour-bearing animals. Radiolabelled TES-23 dramatically accumulated in KMT-17 fibrosarcoma, the source of isolated TECs after intravenous injection. In Meth-A fibrosarcoma, Colon-26 adenocarcinoma in BALB/c mice and HT-1080 human tumour tissue in nude mice, radioactivities of 125I-labelled TES-23 were also up to 50 times higher than those of control antibody with little distribution to normal tissues. The selective recognition of TES-23 to TECs was competitively blocked by preadministration of unlabelled TES-23 in vivo. Furthermore, immunostaining of human tissue sections showed specific binding of TES-23 on endothelium in oesophagus cancers. These results indicate that tumour vascular endothelial cells express common antigen in different tumour types of various animal species. In order to clarify the efficacy of TES-23 as a drug carrier, an immunoconjugate, composed of TES-23 and neocarzinostatin, was tested for its anti-tumour effect in rats bearing KMT-17 fibrosarcomas. The immunoconjugate (TES-23-NCS) caused marked regression of the tumour, accompanied by haemorrhagic necrosis. Thus, from a clinical view, TES-23 would be a novel drug carrier because of its high specificity to tumour vascular endothelium and its application to many types of cancer. © 1999 Cancer Research Campaign PMID:10584876

Distribution of resveratrol and stilbene synthase in young grape plants (Vitis vinifera L. cv. Cabernet Sauvignon) and the effect of UV-C on its accumulation.

PubMed

Wang, Wei; Tang, Ke; Yang, Hao-Ru; Wen, Peng-Fei; Zhang, Ping; Wang, Hui-Ling; Huang, Wei-Dong

2010-01-01

Current research indicated that the resveratrol was mainly accumulated in the skin of grape berry, however, little is yet known about the distribution of resveratrol, as well as the regulation mechanism at protein level and the localization of stilbene synthase (malonyl-CoA:4-coumaroyl-CoA malonyltransferase; EC 2.3.1.95; STS), a key enzyme of resveratrol biosynthesis, in young grape plants (Vitis vinifera L. cv. Cabernet Sauvignon). Resveratrol, whose constitutive level ranged from 0.2 mg kg(-1) FW to 16.5 mg kg(-1) FW, could be detected in stem, axillary bud, shoot tip, petiole, root and leaf of grape plants. Among them, stem phloems presented the most abundant of resveratrol, and the leaves presented the lowest. Interestingly, the level of STS mRNA and protein were highest in grape leaves. And the analysis of immunohistochemical showed the tissue-specific distribution of STS in different organs, presenting the similar results compared with the amount of protein. And the subcellular localization revealed that the cell wall in different tissues processed the most golden particles representing STS. Subjecting to UV-C irradiation, resveratrol and STS were both intensely stimulated in grape leaves, with the similar response pattern. Results above indicated that distribution of resveratrol and STS in grape was organ-specific and tissue-specific. And the accumulation of resveratrol induced by UV-C was regulated by transcriptional and translational level of STS. Copyright 2009 Elsevier Masson SAS. All rights reserved.

Expression and distribution of the transient receptor potential cationic channel ankyrin 1 (TRPA1) in the human vagina.

PubMed

Ückert, S; Sonnenberg, J E; Albrecht, K; Kuczyk, M A; Hedlund, P

2015-01-01

The transient receptor potential cationic channel type A1 (TRPA1), belonging to a superfamily of cationic membrane channels, has been suggested to act as mechano- and pain sensor and, thus, to play a role in neurotransmission in the human body, including the urogenital tract. While the expression of TRPA1 has been investigated in a variety of tissues, up until today, no study has addressed the expression and distribution in the female genital tract. The present study aimed to investigate the expression and distribution of TRPA1 protein in human vaginal tissue. Reverse transcriptase PCR (RT-PCR) was applied in order to identify messenger ribonuleic acid specifically encoding for TRPA/A1. The distribution of TRPA1 in relation to the neuronal nitric oxide synthase (nNOS) and the signaling peptide calcitonin gene-related peptide (CGRP) was examined by means of immunohistochemical methods (double-antibody technique, laser fluorescence microscopy). RT-PCR analysis revealed the expression of mRNA encoding sequences specific for TRPA in the vaginal wall and epithelium. Immunostaining related to TRPA1 was observed in the basal epithelium and in slender varicose nerve fibers transversing the subepithelial and stromal space of the vaginal sections. In addition, these fibers presented immunoreactivity specific for nNOS or CGRP. The smooth musculature of the vaginal wall and small vessels interspersing the tissue did not present signals related to TRPA1. The findings indicate that TRPA1 might be involved in afferent neurotransmission in the vagina and work synergistically together with the nitric oxide/cyclic guanosine monophosphate pathway.

Molecular analysis of tumor margins by MALDI mass spectrometry in renal carcinoma.

PubMed

Oppenheimer, Stacey R; Mi, Deming; Sanders, Melinda E; Caprioli, Richard M

2010-05-07

The rate of tumor recurrence post resection suggests that there are underlying molecular changes in nearby histologically normal tissue that go undetected by conventional diagnostic methods that utilize contrast agents and immunohistochemistry. MALDI MS is a molecular technology that has the specificity and sensitivity to monitor and identify molecular species indicative of these changes. The current study utilizes this technology to assess molecular distributions within a tumor and adjacent normal tissue in clear cell renal cell carcinoma biopsies. Results indicate that the histologically normal tissue adjacent to the tumor expresses many of the molecular characteristics of the tumor. Proteins of the mitochondrial electron transport system are examples of such distributions. This work demonstrates the utility of MALDI MS for the analysis of tumor tissue in the elucidation of aberrant molecular changes in the tumor microenvironment.

Tissue distribution and lipophorin transport of hydrocarbons and sex pheromones in the house fly, Musca domestica

PubMed Central

Schal, Coby; Sevala, Veeresh; de L.Capurro, Margareth; Snyder, Theodore E.; Blomquist, Gary J.; Bagnères, Anne–Geneviève

2001-01-01

We investigated the relationship between epicuticular and internal hydrocarbons in the adult house fly, Musca domestica and the distribution of hydrocarbons, including the female sex pheromone component, (Z)-9-tricosene, in tissues. Internal hydrocarbons increased dramatically in relation to sexual maturation and were found in the hemolymph, ovaries, digestive tract, and fat body. (Z)-9-Tricosene comprised a relatively large fraction of the hydrocarbons in the female carcass and hemolymph, and less so in other tissues, while other hydrocarbons were represented in greater amounts in the ovaries than in other tissues. It therefore appears that certain hydrocarbons were selectively provisioned to certain tissues such as the ovaries, from which pheromone was relatively excluded. Both KBr gradient ultracentrifugation and specific immunoprecipitation indicated that > 90% of hemolymph hydrocarbons were associated with a high-density lipophorin (density = 1.09 g ml−1), composed of two apoproteins under denaturing conditions, apolipophorin I (∼240 kD) and apolipophorin II (∼85 kD). Our results support a predicted model (Chino, 1985) that lipophorin is involved in the transport of sex pheromone in M. domestica. In addition to delivering hydrocarbons and sex pheromones to the cuticular surface, we suggest that lipophorin may play an important role in an active mechanism that selectively deposits certain subsets of hydrocarbons at specific tissues. PMID:15455072

An optimized computational method for determining the beta dose distribution using a multiple-element thermoluminescent dosimeter system.

PubMed

Shen, L; Levine, S H; Catchen, G L

1987-07-01

This paper describes an optimization method for determining the beta dose distribution in tissue, and it describes the associated testing and verification. The method uses electron transport theory and optimization techniques to analyze the responses of a three-element thermoluminescent dosimeter (TLD) system. Specifically, the method determines the effective beta energy distribution incident on the dosimeter system, and thus the system performs as a beta spectrometer. Electron transport theory provides the mathematical model for performing the optimization calculation. In this calculation, parameters are determined that produce calculated doses for each of the chip/absorber components in the three-element TLD system. The resulting optimized parameters describe an effective incident beta distribution. This method can be used to determine the beta dose specifically at 7 mg X cm-2 or at any depth of interest. The doses at 7 mg X cm-2 in tissue determined by this method are compared to those experimentally determined using an extrapolation chamber. For a great variety of pure beta sources having different incident beta energy distributions, good agreement is found. The results are also compared to those produced by a commonly used empirical algorithm. Although the optimization method produces somewhat better results, the advantage of the optimization method is that its performance is not sensitive to the specific method of calibration.

An efficient immunodetection method for histone modifications in plants.

PubMed

Nic-Can, Geovanny; Hernández-Castellano, Sara; Kú-González, Angela; Loyola-Vargas, Víctor M; De-la-Peña, Clelia

2013-12-16

Epigenetic mechanisms can be highly dynamic, but the cross-talk among them and with the genome is still poorly understood. Many of these mechanisms work at different places in the cell and at different times of organism development. Covalent histone modifications are one of the most complex and studied epigenetic mechanisms involved in cellular reprogramming and development in plants. Therefore, the knowledge of the spatial distribution of histone methylation in different tissues is important to understand their behavior on specific cells. Based on the importance of epigenetic marks for biology, we present a simplified, inexpensive and efficient protocol for in situ immunolocalization on different tissues such as flowers, buds, callus, somatic embryo and meristematic tissue from several plants of agronomical and biological importance. Here, we fully describe all the steps to perform the localization of histone modifications. Using this method, we were able to visualize the distribution of H3K4me3 and H3K9me2 without loss of histological integrity of tissues from several plants, including Agave tequilana, Capsicum chinense, Coffea canephora and Cedrela odorata, as well as Arabidopsis thaliana. There are many protocols to study chromatin modifications; however, most of them are expensive, difficult and require sophisticated equipment. Here, we provide an efficient protocol for in situ localization of histone methylation that dispenses with the use of expensive and sensitive enzymes. The present method can be used to investigate the cellular distribution and localization of a wide array of proteins, which could help to clarify the biological role that they play at specific times and places in different tissues of various plant species.

Tissue-specific proportions of phylloquinone to menaquinone-4 concentrations differ in response to dietary phylloquinone manipulation in lean male Zucker rats

USDA-ARS?s Scientific Manuscript database

Phylloquinone (PK) and menaquinone (MK) are naturally-occurring forms of vitamin K (VK). There is selective tissue distribution and conversion of dietary PK to MK4, providing indirect evidence of unique MK4 functions beyond those established for PK. We determined the effect of dietary PK manipulatio...

Distribution of potential eye and tissue donors within an Australian teaching hospital.

PubMed

Dutch, Martin J; Denahy, Anthony F

2017-12-11

Eye and Tissue donation has the capacity to transform lives, yet the vast majority of potential in-hospital donors are not recognised. Studies which describe the relative importance of specific units or wards in determining the size of the donor pool are limited. The aim of this study was to map the distribution of potential Eye and Tissue donors within the study hospital. A 12-month retrospective analysis of all patient deaths at the study hospital was undertaken. The ability to donate corneal, heart valve, bone and skin tissue was investigated. Patients were classified as potential donors if they met specific age criteria and had an absence of contraindications based on electronic database search. There were 985 deaths during the study period. Deaths occurred under the care of 26 separate clinical units, and within 28 unique wards and treatment spaces. Four hundred and forty nine (45.6%) patients were identified as potential eye or tissue donors. The majority of potential donors occurred in ICU, Emergency and palliative care units. Of the subset of 328 deaths ≤ 70 years, the frequency of potential tissue donors was 55% (n = 181). ED and ICU had significantly higher frequencies of potential donor than other wards (86 and 77%, p < 0.01). The current study has identified the ED, ICU and PCUs are being important sites for potential Eye and Tissue Donors within our hospital. These will provide an important focus for future interventions to improve the rate of eye and tissue donation.

Tissue accumulation of microplastics in mice and biomarker responses suggest widespread health risks of exposure

NASA Astrophysics Data System (ADS)

Deng, Yongfeng; Zhang, Yan; Lemos, Bernardo; Ren, Hongqiang

2017-04-01

Microplastics (MPs) are a significant environmental health issue and increasingly greater source of concern. MPs have been detected in oceans, rivers, sediments, sewages, soil and even table salts. MPs exposure on marine organisms and humans has been documented, but information about the toxicity of MPs in mammal is limited. Here we used fluorescent and pristine polystyrene microplastics (PS-MPs) particles with two diameters (5 μm and 20 μm) to investigate the tissue distribution, accumulation, and tissue-specific health risk of MPs in mice. Results indicated that MPs accumulated in liver, kidney and gut, with a tissue-accumulation kinetics and distribution pattern that was strongly depended on the MPs particle size. In addition, analyses of multiple biochemical biomarkers and metabolomic profiles suggested that MPs exposure induced disturbance of energy and lipid metabolism as well as oxidative stress. Interestingly, blood biomarkers of neurotoxicity were also altered. Our results uncovered the distribution and accumulation of MPs across mice tissues and revealed significant alteration in several biomarkers that indicate potential toxicity from MPs exposure. Collectively, our data provided new evidence for the adverse consequences of MPs.

Tissue accumulation of microplastics in mice and biomarker responses suggest widespread health risks of exposure

PubMed Central

Deng, Yongfeng; Zhang, Yan; Lemos, Bernardo; Ren, Hongqiang

2017-01-01

Microplastics (MPs) are a significant environmental health issue and increasingly greater source of concern. MPs have been detected in oceans, rivers, sediments, sewages, soil and even table salts. MPs exposure on marine organisms and humans has been documented, but information about the toxicity of MPs in mammal is limited. Here we used fluorescent and pristine polystyrene microplastics (PS-MPs) particles with two diameters (5 μm and 20 μm) to investigate the tissue distribution, accumulation, and tissue-specific health risk of MPs in mice. Results indicated that MPs accumulated in liver, kidney and gut, with a tissue-accumulation kinetics and distribution pattern that was strongly depended on the MPs particle size. In addition, analyses of multiple biochemical biomarkers and metabolomic profiles suggested that MPs exposure induced disturbance of energy and lipid metabolism as well as oxidative stress. Interestingly, blood biomarkers of neurotoxicity were also altered. Our results uncovered the distribution and accumulation of MPs across mice tissues and revealed significant alteration in several biomarkers that indicate potential toxicity from MPs exposure. Collectively, our data provided new evidence for the adverse consequences of MPs. PMID:28436478

Light source distribution and scattering phase function influence light transport in diffuse multi-layered media

NASA Astrophysics Data System (ADS)

Vaudelle, Fabrice; L'Huillier, Jean-Pierre; Askoura, Mohamed Lamine

2017-06-01

Red and near-Infrared light is often used as a useful diagnostic and imaging probe for highly scattering media such as biological tissues, fruits and vegetables. Part of diffusively reflected light gives interesting information related to the tissue subsurface, whereas light recorded at further distances may probe deeper into the interrogated turbid tissues. However, modelling diffusive events occurring at short source-detector distances requires to consider both the distribution of the light sources and the scattering phase functions. In this report, a modified Monte Carlo model is used to compute light transport in curved and multi-layered tissue samples which are covered with a thin and highly diffusing tissue layer. Different light source distributions (ballistic, diffuse or Lambertian) are tested with specific scattering phase functions (modified or not modified Henyey-Greenstein, Gegenbauer and Mie) to compute the amount of backscattered and transmitted light in apple and human skin structures. Comparisons between simulation results and experiments carried out with a multispectral imaging setup confirm the soundness of the theoretical strategy and may explain the role of the skin on light transport in whole and half-cut apples. Other computational results show that a Lambertian source distribution combined with a Henyey-Greenstein phase function provides a higher photon density in the stratum corneum than in the upper dermis layer. Furthermore, it is also shown that the scattering phase function may affect the shape and the magnitude of the Bidirectional Reflectance Distribution (BRDF) exhibited at the skin surface.

Tissue-specific distribution of hemicelluloses in six different sugarcane hybrids as related to cell wall recalcitrance

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

Costa, Thales H. F.; Vega-Sánchez, Miguel E.; Milagres, Adriane M. F.

Background: Grasses are lignocellulosic materials useful to supply the billion-tons annual requirement for renewable resources that aim to produce transportation fuels and a variety of chemicals. However, the polysaccharides contained in grass cell walls are built in a recalcitrant composite. Deconstruction of these cell walls is still a challenge for the energy-efficient and economically viable transformation of lignocellulosic materials. The varied tissue-specific distribution of cell wall components adds complexity to the origins of cell wall recalcitrance in grasses. This complexity usually led to empirically developed pretreatment processes to overcome recalcitrance. A further complication is that efficient pretreatment procedures generally treatmore » the less recalcitrant tissues more than necessary, which results in the generation of undesirable biomass degradation products. Results: Six different sugarcane hybrids were used as model grasses to evaluate the tissue-specific distribution of hemicelluloses and the role of these components in cell wall recalcitrance. Acetylated glucuronoarabinoxylan (GAX) occurs in all tissues. Mixed-linkage glucan (MLG) was relevant in the innermost regions of the sugarcane internodes (up to 15.4 % w/w), especially in the low-lignin content hybrids. Immunofluorescence microscopy showed that xylans predominated in vascular bundles, whereas MLG occurred mostly in the parenchyma cell walls from the pith region of the hybrids with low-lignin content. Evaluation of the digestibility of sugarcane polysaccharides by commercial enzymes indicated that the cell wall recalcitrance varied considerably along the internode regions and in the sugarcane hybrids. Pith regions of the hybrids with high MLG and low-lignin contents reached up to 85 % cellulose conversion after 72 h of hydrolysis, without any pretreatment. Conclusions: The collective characteristics of the internode regions were related to the varied recalcitrance found in the samples. Components such as lignin and GAX were critical for the increased recalcitrance, but low cellulose crystallinity index, high MLG contents, and highly substituted GAX contributed to the generation of a less recalcitrant material.« less

Tissue-specific distribution of hemicelluloses in six different sugarcane hybrids as related to cell wall recalcitrance

DOE PAGES

Costa, Thales H. F.; Vega-Sánchez, Miguel E.; Milagres, Adriane M. F.; ...

2016-05-04

Background: Grasses are lignocellulosic materials useful to supply the billion-tons annual requirement for renewable resources that aim to produce transportation fuels and a variety of chemicals. However, the polysaccharides contained in grass cell walls are built in a recalcitrant composite. Deconstruction of these cell walls is still a challenge for the energy-efficient and economically viable transformation of lignocellulosic materials. The varied tissue-specific distribution of cell wall components adds complexity to the origins of cell wall recalcitrance in grasses. This complexity usually led to empirically developed pretreatment processes to overcome recalcitrance. A further complication is that efficient pretreatment procedures generally treatmore » the less recalcitrant tissues more than necessary, which results in the generation of undesirable biomass degradation products. Results: Six different sugarcane hybrids were used as model grasses to evaluate the tissue-specific distribution of hemicelluloses and the role of these components in cell wall recalcitrance. Acetylated glucuronoarabinoxylan (GAX) occurs in all tissues. Mixed-linkage glucan (MLG) was relevant in the innermost regions of the sugarcane internodes (up to 15.4 % w/w), especially in the low-lignin content hybrids. Immunofluorescence microscopy showed that xylans predominated in vascular bundles, whereas MLG occurred mostly in the parenchyma cell walls from the pith region of the hybrids with low-lignin content. Evaluation of the digestibility of sugarcane polysaccharides by commercial enzymes indicated that the cell wall recalcitrance varied considerably along the internode regions and in the sugarcane hybrids. Pith regions of the hybrids with high MLG and low-lignin contents reached up to 85 % cellulose conversion after 72 h of hydrolysis, without any pretreatment. Conclusions: The collective characteristics of the internode regions were related to the varied recalcitrance found in the samples. Components such as lignin and GAX were critical for the increased recalcitrance, but low cellulose crystallinity index, high MLG contents, and highly substituted GAX contributed to the generation of a less recalcitrant material.« less

Glycosphingolipid storage in Fabry mice extends beyond globotriaosylceramide and is affected by ABCB1 depletion

PubMed Central

Kamani, Mustafa A; Provençal, Philippe; Boutin, Michel; Pacienza, Natalia; Fan, Xin; Novak, Anton; Huang, Tonny C; Binnington, Beth; Au, Bryan C; Auray-Blais, Christiane; Lingwood, Clifford A; Medin, Jeffrey A

2016-01-01

Aim: Fabry disease is caused by α-galactosidase A deficiency leading to accumulation of globotriaosylceramide (Gb3) in tissues. Clinical manifestations do not appear to correlate with total Gb3 levels. Studies examining tissue distribution of specific acyl chain species of Gb3 and upstream glycosphingolipids are lacking. Material & methods/Results: Thorough characterization of the Fabry mouse sphingolipid profile by LC-MS revealed unique Gb3 acyl chain storage profiles. Storage extended beyond Gb3; all Fabry tissues also accumulated monohexosylceramides. Depletion of ABCB1 had a complex effect on glycosphingolipid storage. Conclusion: These data provide insights into how specific sphingolipid species correlate with one another and how these correlations change in the α-galactosidase A-deficient state, potentially leading to the identification of more specific biomarkers of Fabry disease. PMID:28116130

Tissue distribution of co-planar and non-planar tetra- and hexa-chlorobiphenyl isomers in guinea pigs after oral ingestion

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

Jan, J.; Logar, B.; Jan, J.

1996-03-01

Food ingestion is the most important route for the uptake of lipophilic organochlorine contaminants. Uptake and transfer of the contaminants from the digestive tract to target organs can be used for risk evaluation. The bioconcentration and migration of polychlorobiphenyls (PCBs) is highly structure - dependent. Bioconcentration is correlated with lipophilicity on the basis of the n-octanol/water partition coefficient in its logarithmic form - logKow. However, some factors e.g. diffusion through cell membranes, accumulation in specific organs and tissues, uptake and deputation kinetics and metabolism can also influence the bioconcentration. Individual PCB compounds of commercial PCB preparation are taken up bymore » organisms to markedly different extents. Until now little is known about the distribution of non-planar and co-planar PCBs in different tissues. Co-planar PCBs have dioxin - like toxicity. This study examines differences in the bioconcentration of two pairs of tetra and hexa chlorobiphenyls from the digestive tract and their distribution in different tissues of guinea pigs.« less

Validated UPLC-MS/MS method for quantification of seven compounds in rat plasma and tissues: Application to pharmacokinetic and tissue distribution studies in rats after oral administration of extract of Eclipta prostrata L.

PubMed

Du, Guangyan; Fu, Lingling; Jia, Jun; Pang, Xu; Yu, Haiyang; Zhang, Youcai; Fan, Guanwei; Gao, Xiumei; Han, Lifeng

2018-06-01

A rapid, sensitive and specific ultra-high-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) method was developed to investigate the pharmacokinetics and tissue distribution of Eclipta prostrata extract. Rats were orally administrated the 70% ethanol extract of E. prostrata, and their plasma as well as various organs were collected. The concentrations of seven main compounds, ecliptasaponin IV, ecliptasaponin A, apigenin, 3'-hydroxybiochanin A, luteolin, luteolin-7-O-glucoside and wedelolactone, were quantified by UPLC-MS/MS through multiple reactions monitoring method. The precisions (RSD) of the analytes were all <15.00%. The extraction recoveries ranged from 74.65 to 107.45% with RSD ≤ 15.36%. The matrix effects ranged from 78.00 to 118.06% with RSD ≤ 15.04%. To conclude, the present pharmacokinetic and tissue distribution studies provided useful information for the clinical usage of Eclipta prostrata L. Copyright © 2018 John Wiley & Sons, Ltd.

Heat shock protein 60 expression in heart, liver and kidney of broilers exposed to high temperature.

PubMed

Yan, Jianyan; Bao, Endong; Yu, Jimian

2009-06-01

The objective of this study was to investigate the expression and localization of HSP60 in the heart, liver, and kidney of acutely heat-stressed broilers at various stressing times. The plasma creatine kinase (CK) and glutamic pyruvic transaminase (GPT) concentrations statistic increased following heat stress. After 2h of heat stress, the tissues showed histopathological changes. Hsp60 expressed mainly in the cytoplasm of parenchyma cells heat stress. The intensity of the cytoplasmic staining varied and exhibited an organ-specific distribution pattern. Hsp60 levels in the hearts of heat-stressed chickens gradually increased at 1h (p<0.05) and peaked (p<0.05) at 5h; Hsp60 levels in the liver gradually decreased at 3h (p<0.05); Hsp60 levels in the kidney had no fluctuation. It is suggested that Hsp60 expression is tissue-specific and this may be linked to tissue damage in response to heat stress. The Hsp60 level is distinct in diverse tissues, indicating that Hsp60 may exert its protective effect by a tissue- and time-specific mechanism.

In situ enzymatic activity of transglutaminase isoforms on brain tissue sections of rodents: A new approach to monitor differences in post-translational protein modifications during neurodegeneration.

PubMed

Schulze-Krebs, Anja; Canneva, Fabio; Schnepf, Rebecca; Dobner, Julia; Dieterich, Walburga; von Hörsten, Stephan

2016-01-15

Mammalian transglutaminases (TGs) catalyze the irreversible post-translational modifications of proteins, the most prominent of which is the calcium-dependent formation of covalent acyl transfers between the γ-carboxamide group of glutamine and the ε-amino-group of lysine (GGEL-linkage). In the central nervous system, at least four TG isoforms are present and some of them are differentially expressed under pathological conditions in human patients. However, the precise TG-isoform-dependent enzymatic activities in the brain as well as their anatomical distribution are unknown. Specificity of the used biotinylated peptides was analyzed using an in vitro assay. Isoform-specific TG activity was evaluated in in vitro and in situ studies, using brain extracts and native brain tissue obtained from rodents. Our method allowed us to reveal in vitro and in situ TG-isoform-dependent enzymatic activity in brain extracts and tissue of rats and mice, with a specific focus on TG6. In situ activity of this isoform varied between BACHD mice in comparison to their wt controls. TG isozyme-specific activity can be detected by isoform-specific biotinylated peptides in brain tissue sections of rodents to reveal differences in the anatomical and/or subcellular distribution of TG activity. Our findings yield the basis for a broader application of this method for the screening of pathological expression and activity of TGs in a variety of animal models of human diseases, as in the case of neurodegenerative conditions such as Huntington׳s, Parkinson׳s and Alzheimer׳s, where protein modification is involved as a key mechanism of disease progression. Copyright © 2015 Elsevier B.V. All rights reserved.

Distribution of Potato virus Y in potato plant organs, tissues, and cells.

PubMed

Kogovšek, P; Kladnik, A; Mlakar, J; Znidarič, M Tušek; Dermastia, M; Ravnikar, M; Pompe-Novak, M

2011-11-01

The distribution of Potato virus Y (PVY) in the systemically infected potato (Solanum tuberosum) plants of the highly susceptible cultivar Igor was investigated. Virus presence and accumulation was analyzed in different plant organs and tissues using real-time polymerase chain reaction and transmission electron microscopy (TEM) negative staining methods. To get a complete insight into the location of viral RNA within the tissue, in situ hybridization was developed and optimized for the detection of PVY RNA at the cellular level. PVY was shown to accumulate in all studied leaf and stem tissues, in shoot tips, roots, and tubers; however, the level of virus accumulation was specific for each organ or tissue. The highest amounts of viral RNA and viral particles were found in symptomatic leaves and stem. By observing cell ultrastructure with TEM, viral cytoplasmic inclusion bodies were localized in close vicinity to the epidermis and in trichomes. Our results show that viral RNA, viral particles, and cytoplasmic inclusion bodies colocalize within the same type of cells or in close vicinity.

A Chemoenzymatic Histology Method for O-GlcNAc Detection.

PubMed

Aguilar, Aime Lopez; Hou, Xiaomeng; Wen, Liuqing; Wang, Peng G; Wu, Peng

2017-12-14

Modification of nuclear and cytoplasmic proteins by the addition or removal of O-GlcNAc dynamically impacts multiple biological processes. Here, we present the development of a chemoenzymatic histology method for the detection of O-GlcNAc in tissue specimens. We applied this method to screen murine organs, uncovering specific O-GlcNAc distribution patterns in different tissue structures. We then utilized our histology method for O-GlcNAc detection in human brain specimens from healthy donors and donors with Alzheimer's disease and found higher levels of O-GlcNAc in specimens from healthy donors. We also performed an analysis using a multiple cancer tissue array, uncovering different O-GlcNAc levels between healthy and cancerous tissues, as well as different O-GlcNAc cellular distributions within certain tissue specimens. This chemoenzymatic histology method therefore holds great potential for revealing the biology of O-GlcNAc in physiopathological processes. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Distribution of hexadecenoic, octadecenoic and octadecadienoic acid isomers in human tissue lipids.

PubMed

Adlof, R O; Emken, E A

1986-09-01

The trans 16:1, 18:1 and 18:2 fatty acid composition of various human organ lipids was studied to determine if isomers accumulated in specific tissues. "Trans" isomers are defined as those fatty acids containing one or more trans double bonds. Adipose, kidney, brain, heart and liver tissue lipids were analyzed. Gas chromatography with a 100-SP2560 capillary column was used to characterize the various positional and/or geometrical isomers. The distribution of trans 16:1 and 18:1 isomers ranged from 0.3% in the brain to 4.0% in adipose tissue, while trans 18:2 isomers ranged from 0.0% in the brain to 0.4% in adipose tissue. No trans 18:3 isomers were detected. Positional isomer ratios for cis 16:1 (delta 9 vs delta 7) and cis 18:1 (delta 11 vs delta 9) were also determined. Since these ratios are reproducible from one individual to the next, they might be useful for diagnosis of human metabolic disorders.

A study of a tissue equivalent gelatine based tissue substitute

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

Spence, J.L.

1992-11-01

A study of several tissue substitutes for use as volumetric dosimeters was performed. The tissue substitutes studied included tissue substitutes from previous studies and from ICRU 44. The substitutes were evaluated for an overall match to Reference Man which was used as a basis for this study. The evaluation was based on the electron stopping power, the mass attenuation coefficient, the electron density, and the specific gravity. The tissue substitute chosen also had to be capable of changing from a liquid into a solid form to maintain an even distribution of thermoluminesent dosimetry (TLD) powder and then back to amore » liquid for recovery of the TLD powder without adversely effecting the TLD powder. The gelatine mixture provided the closest match to the data from Reference Man tissue. The gelatine mixture was put through a series of test to determine it's usefulness as a reliable tissue substitute. The TLD powder was cast in the gelatine mixture and recovered to determine if the TLD powder was adversely effected. The distribution of the TLD powder after being cast into the gelatin mixture was tested in insure an even was maintained.« less

A study of a tissue equivalent gelatine based tissue substitute

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

Spence, Jody L.

1992-11-01

A study of several tissue substitutes for use as volumetric dosimeters was performed. The tissue substitutes studied included tissue substitutes from previous studies and from ICRU 44. The substitutes were evaluated for an overall match to Reference Man which was used as a basis for this study. The evaluation was based on the electron stopping power, the mass attenuation coefficient, the electron density, and the specific gravity. The tissue substitute chosen also had to be capable of changing from a liquid into a solid form to maintain an even distribution of thermoluminesent dosimetry (TLD) powder and then back to amore » liquid for recovery of the TLD powder without adversely effecting the TLD powder. The gelatine mixture provided the closest match to the data from Reference Man tissue. The gelatine mixture was put through a series of test to determine it`s usefulness as a reliable tissue substitute. The TLD powder was cast in the gelatine mixture and recovered to determine if the TLD powder was adversely effected. The distribution of the TLD powder after being cast into the gelatin mixture was tested in insure an even was maintained.« less

Estrogen receptor-independent catechol estrogen binding activity: protein binding studies in wild-type, Estrogen receptor-alpha KO, and aromatase KO mice tissues.

PubMed

Philips, Brian J; Ansell, Pete J; Newton, Leslie G; Harada, Nobuhiro; Honda, Shin-Ichiro; Ganjam, Venkataseshu K; Rottinghaus, George E; Welshons, Wade V; Lubahn, Dennis B

2004-06-01

Primary evidence for novel estrogen signaling pathways is based upon well-documented estrogenic responses not inhibited by estrogen receptor antagonists. In addition to 17beta-E2, the catechol estrogen 4-hydroxyestradiol (4OHE2) has been shown to elicit biological responses independent of classical estrogen receptors in estrogen receptor-alpha knockout (ERalphaKO) mice. Consequently, our research was designed to biochemically characterize the protein(s) that could be mediating the biological effects of catechol estrogens using enzymatically synthesized, radiolabeled 4-hydroxyestrone (4OHE1) and 4OHE2. Scatchard analyses identified a single class of high-affinity (K(d) approximately 1.6 nM), saturable cytosolic binding sites in several ERalphaKO estrogen-responsive tissues. Specific catechol estrogen binding was competitively inhibited by unlabeled catechol estrogens, but not by 17beta-E2 or the estrogen receptor antagonist ICI 182,780. Tissue distribution studies indicated significant binding differences both within and among various tissues in wild-type, ERalphaKO, and aromatase knockout female mice. Ligand metabolism experiments revealed extensive metabolism of labeled catechol estrogen, suggesting that catechol estrogen metabolites were responsible for the specific binding. Collectively, our data provide compelling evidence for the interaction of catechol estrogen metabolites with a novel binding protein that exhibits high affinity, specificity, and selective tissue distribution. The extensive biochemical characterization of this binding protein indicates that this protein may be a receptor, and thus may mediate ERalpha/beta-independent effects of catechol estrogens and their metabolites.

Differential distribution of annexins-I, -II, -IV, and -VI in synovium.

PubMed Central

Goulding, N J; Dixey, J; Morand, E F; Dodds, R A; Wilkinson, L S; Pitsillides, A A; Edwards, J C

1995-01-01

OBJECTIVES--To examine the distribution of four annexins in non-inflamed rheumatoid arthritic and osteoarthritic synovial tissue. METHODS--Frozen sections were stained with monoclonal antibodies (MAb) specific for annexins-I, -II, -IV, and -VI, and for cell lineage related markers including CD68 and CD14 (macrophages), prolyl hydroxylase (fibroblasts), and CD3 (T cells). RESULTS--Each of the annexins was present in synovial tissues in significant amounts in the three groups studied. Annexin-I was predominantly found within the synovial lining layer and double labelling showed it to be present predominantly in cells of the macrophage lineage. In rheumatoid specimens there was increased staining within the lining layer, perivascularly and on macrophages within the tissue stroma. Annexin-II was present in a distribution similar to that of annexin-I, but with more prominent perivascular staining. Annexins-IV and -VI were seen chiefly in association with areas of lymphocyte infiltration in rheumatoid tissue, whereas annexins-I and -II were absent from these areas. Endothelial cells stained weakly positive for annexins-I and -II, and more strongly for -IV and -VI. CONCLUSIONS--This study demonstrates that annexins (particularly annexin-I, a putative mediator of the anti-inflammatory activities of glucocorticoids) are abundant in rheumatoid and non-rheumatoid synovial tissue, annexins-IV and -VI having a distribution distinct from that of -I and -II. Images PMID:7492225

A systematic survey of lipids across mouse tissues

PubMed Central

Jain, Mohit; Ngoy, Soeun; Sheth, Sunil A.; Swanson, Raymond A.; Rhee, Eugene P.; Liao, Ronglih; Clish, Clary B.; Mootha, Vamsi K.

2014-01-01

Lipids are a diverse collection of macromolecules essential for normal physiology, but the tissue distribution and function for many individual lipid species remain unclear. Here, we report a mass spectrometry survey of lipid abundance across 18 mouse tissues, detecting ∼1,000 mass spectrometry features, of which we identify 179 lipids from the glycerolipids, glycerophospholipids, lysophospholipids, acylcarnitines, sphingolipids, and cholesteryl ester classes. Our data reveal tissue-specific organization of lipids and can be used to generate testable hypotheses. For example, our data indicate that circulating triglycerides positively and negatively associated with future diabetes in humans are enriched in mouse adipose tissue and liver, respectively, raising hypotheses regarding the tissue origins of these diabetes-associated lipids. We also integrate our tissue lipid data with gene expression profiles to predict a number of substrates of lipid-metabolizing enzymes, highlighting choline phosphotransferases and sterol O-acyltransferases. Finally, we identify several tissue-specific lipids not present in plasma under normal conditions that may be of interest as biomarkers of tissue injury, and we show that two of these lipids are released into blood following ischemic brain injury in mice. This resource complements existing compendia of tissue gene expression and may be useful for integrative physiology and lipid biology. PMID:24518676

A method for the assessment of specific energy distribution in a model tumor system

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

Noska, M.A.

1996-12-31

Due to the short range of alpha particles in tissue, the calculation of dose from internally deposited alpha emitters requires a detailed analysis of the microscopic distribution of the radionuclide in order to determine the spatial distribution of energy emission events and, from this, the spatial distribution of dose. In the present study, the authors used quantitative autoradiography (QAR) to assess the microdistribution of a radiolabeled monoclonal antibody (MAb) fragment in human glioma xenografts in mice.

Polymer powder processing of cryomilled polycaprolactone for solvent-free generation of homogeneous bioactive tissue engineering scaffolds.

PubMed

Lim, Jing; Chong, Mark Seow Khoon; Chan, Jerry Kok Yen; Teoh, Swee-Hin

2014-06-25

Synthetic polymers used in tissue engineering require functionalization with bioactive molecules to elicit specific physiological reactions. These additives must be homogeneously dispersed in order to achieve enhanced composite mechanical performance and uniform cellular response. This work demonstrates the use of a solvent-free powder processing technique to form osteoinductive scaffolds from cryomilled polycaprolactone (PCL) and tricalcium phosphate (TCP). Cryomilling is performed to achieve micrometer-sized distribution of PCL and reduce melt viscosity, thus improving TCP distribution and improving structural integrity. A breakthrough is achieved in the successful fabrication of 70 weight percentage of TCP into a continuous film structure. Following compaction and melting, PCL/TCP composite scaffolds are found to display uniform distribution of TCP throughout the PCL matrix regardless of composition. Homogeneous spatial distribution is also achieved in fabricated 3D scaffolds. When seeded onto powder-processed PCL/TCP films, mesenchymal stem cells are found to undergo robust and uniform osteogenic differentiation, indicating the potential application of this approach to biofunctionalize scaffolds for tissue engineering applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Assessment of the systemic distribution of a bioconjugated anti-Her2 magnetic nanoparticle in a breast cancer model by means of magnetic resonance imaging

NASA Astrophysics Data System (ADS)

Huerta-Núñez, L. F. E.; Villanueva-Lopez, G. Cleva; Morales-Guadarrama, A.; Soto, S.; López, J.; Silva, J. G.; Perez-Vielma, N.; Sacristán, E.; Gudiño-Zayas, Marco E.; González, C. A.

2016-09-01

The aim of this study was to determine the systemic distribution of magnetic nanoparticles of 100 nm diameter (MNPs) coupled to a specific monoclonal antibody anti-Her2 in an experimental breast cancer (BC) model. The study was performed in two groups of Sprague-Dawley rats: control ( n = 6) and BC chemically induced ( n = 3). Bioconjugated "anti-Her2-MNPs" were intravenously administered, and magnetic resonance imaging (MRI) monitored its systemic distribution at seven times after administration. Non-heme iron presence associated with the location of the bioconjugated anti-Her2-MNPs in splenic, hepatic, cardiac and tumor tissues was detected by Perl's Prussian blue (PPB) stain. Optical density measurements were used to semiquantitatively determine the iron presence in tissues on the basis of a grayscale values integration of T1 and T2 MRI sequence images. The results indicated a delayed systemic distribution of MNPs in cancer compared to healthy conditions with a maximum concentration of MNPs in cancer tissue at 24 h post-infusion.

Neutralization-resistant variants of infectious hematopoietic necrosis virus have altered virulence and tissue tropism

USGS Publications Warehouse

Kim, C.H.; Winton, J.R.; Leong, J.C.

1994-01-01

Infectious hematopoietic necrosis virus (IHNV) is a rhabdovirus that causes an acute disease in salmon and trout. In this study, a correlation between changes in tissue tropism and specific changes in the virus genome appeared to be made by examining four IHNV neutralization-resistant variants (RB-1, RB-2, RB-3, and RB-4) that had been selected with the glycoprotein (G)-specific monoclonal antibody RB/B5. These variants were compared with the parental strain (RB-76) for their virulence and pathogenicity in rainbow trout after waterborne challenge. Variants RB-2, RB-3, and RB-4 were only slightly attenuated and showed distributions of viral antigen in the livers and hematopoietic tissues of infected fish similar to those of the parental strain. Variant RB-1, however, was highly attenuated and the tissue distribution of viral antigen in RB-1-infected fish was markedly different, with more viral antigen in brain tissue. The sequences of the G genes of all four variants and RB-76 were determined. No significant changes were found for the slightly attenuated variants, but RB-1 G had two changes at amino acids 78 and 218 that dramatically altered its predicted secondary structure. These changes are thought to be responsible for the altered tissue tropism of the virus. Thus, IHNV G, like that of rabies virus and vesicular stomatitis virus, plays an integral part in the pathogenesis of viral infection.

Vascular gene expression: a hypothesis

PubMed Central

Martínez-Navarro, Angélica C.; Galván-Gordillo, Santiago V.; Xoconostle-Cázares, Beatriz; Ruiz-Medrano, Roberto

2013-01-01

The phloem is the conduit through which photoassimilates are distributed from autotrophic to heterotrophic tissues and is involved in the distribution of signaling molecules that coordinate plant growth and responses to the environment. Phloem function depends on the coordinate expression of a large array of genes. We have previously identified conserved motifs in upstream regions of the Arabidopsis genes, encoding the homologs of pumpkin phloem sap mRNAs, displaying expression in vascular tissues. This tissue-specific expression in Arabidopsis is predicted by the overrepresentation of GA/CT-rich motifs in gene promoters. In this work we have searched for common motifs in upstream regions of the homologous genes from plants considered to possess a “primitive” vascular tissue (a lycophyte), as well as from others that lack a true vascular tissue (a bryophyte), and finally from chlorophytes. Both lycophyte and bryophyte display motifs similar to those found in Arabidopsis with a significantly low E-value, while the chlorophytes showed either a different conserved motif or no conserved motif at all. These results suggest that these same genes are expressed coordinately in non-vascular plants; this coordinate expression may have been one of the prerequisites for the development of conducting tissues in plants. We have also analyzed the phylogeny of conserved proteins that may be involved in phloem function and development. The presence of CmPP16, APL, FT, and YDA in chlorophytes suggests the recruitment of ancient regulatory networks for the development of the vascular tissue during evolution while OPS is a novel protein specific to vascular plants. PMID:23882276

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

Ryan, J.W.; Anderson, D.R.

Eye tissues contain kininase activities, including an angiotensin converting enzyme (ACE)-like activity. The authors have begun further to characterize the ACE-like activity and to examine for another reputed kininase, carboxypeptidase N (CPN). Homogenates of tissues of 6 cat eyes and paired plasmas were assayed for ACE using 3 acyl-tripeptide substrates, /sup 3/H-benzoylated F-A-P, F-G-P and A-G-P (respectively, BFAP, BFGP and BAGP). CPN was assayed using /sup 3/H-benzoyl-A-R. All eye tissues and fluids contained ACE- and CPN-like activities. The ACE activity was clearly owing to ACE: relative values of Kc/Km for BFAP, BFGP and BAGP were those for pure ACE (2.213,more » 1.751 and 1.0); reactivities with inhibitors were as expected (Ki for captopril, MK 422 and RAC-X-65: 2.7, 0.62 and 0.31 nM). EDTA inhibited both ACE and CPN (I/sub 50/'s: 43 and 47 ..mu..M). CPN activity was inhibited by 2-mercaptomethyl-3-guanidinoethylthiopropionate (Ki 2.4 nM). However, distributions of the two enzymes differed markedly. Virtually all tissues contained ACE at specific activities higher than that of plasma. Specific activities appeared to be a function of tissue vascularity (for choroid, ciliary body, iris, retina and plasma: 7.31, 2.57, 1.98, 1.53 and 0.21 pmol/mg protein). Only iris contained more CPN that did plasma (23.0 v. 7.21 pmol/mg protein). The tissue distribution of ACE is that expected for an endothelial-associated enzyme. Plasma may be the major source of CPN in eye tissues other than iris.« less

Modeling of electric field distribution in tissues during electroporation

PubMed Central

2013-01-01

Background Electroporation based therapies and treatments (e.g. electrochemotherapy, gene electrotransfer for gene therapy and DNA vaccination, tissue ablation with irreversible electroporation and transdermal drug delivery) require a precise prediction of the therapy or treatment outcome by a personalized treatment planning procedure. Numerical modeling of local electric field distribution within electroporated tissues has become an important tool in treatment planning procedure in both clinical and experimental settings. Recent studies have reported that the uncertainties in electrical properties (i.e. electric conductivity of the treated tissues and the rate of increase in electric conductivity due to electroporation) predefined in numerical models have large effect on electroporation based therapy and treatment effectiveness. The aim of our study was to investigate whether the increase in electric conductivity of tissues needs to be taken into account when modeling tissue response to the electroporation pulses and how it affects the local electric distribution within electroporated tissues. Methods We built 3D numerical models for single tissue (one type of tissue, e.g. liver) and composite tissue (several types of tissues, e.g. subcutaneous tumor). Our computer simulations were performed by using three different modeling approaches that are based on finite element method: inverse analysis, nonlinear parametric and sequential analysis. We compared linear (i.e. tissue conductivity is constant) model and non-linear (i.e. tissue conductivity is electric field dependent) model. By calculating goodness of fit measure we compared the results of our numerical simulations to the results of in vivo measurements. Results The results of our study show that the nonlinear models (i.e. tissue conductivity is electric field dependent: σ(E)) fit experimental data better than linear models (i.e. tissue conductivity is constant). This was found for both single tissue and composite tissue. Our results of electric field distribution modeling in linear model of composite tissue (i.e. in the subcutaneous tumor model that do not take into account the relationship σ(E)) showed that a very high electric field (above irreversible threshold value) was concentrated only in the stratum corneum while the target tumor tissue was not successfully treated. Furthermore, the calculated volume of the target tumor tissue exposed to the electric field above reversible threshold in the subcutaneous model was zero assuming constant conductivities of each tissue. Our results also show that the inverse analysis allows for identification of both baseline tissue conductivity (i.e. conductivity of non-electroporated tissue) and tissue conductivity vs. electric field (σ(E)) of electroporated tissue. Conclusion Our results of modeling of electric field distribution in tissues during electroporation show that the changes in electrical conductivity due to electroporation need to be taken into account when an electroporation based treatment is planned or investigated. We concluded that the model of electric field distribution that takes into account the increase in electric conductivity due to electroporation yields more precise prediction of successfully electroporated target tissue volume. The findings of our study can significantly contribute to the current development of individualized patient-specific electroporation based treatment planning. PMID:23433433

Perivascular Adipose Tissue as a Relevant Fat Depot for Cardiovascular Risk in Obesity.

PubMed

Costa, Rafael M; Neves, Karla B; Tostes, Rita C; Lobato, Núbia S

2018-01-01

Obesity is associated with increased risk of premature death, morbidity, and mortality from several cardiovascular diseases (CVDs), including stroke, coronary heart disease (CHD), myocardial infarction, and congestive heart failure. However, this is not a straightforward relationship. Although several studies have substantiated that obesity confers an independent and additive risk of all-cause and cardiovascular death, there is significant variability in these associations, with some lean individuals developing diseases and others remaining healthy despite severe obesity, the so-called metabolically healthy obese. Part of this variability has been attributed to the heterogeneity in both the distribution of body fat and the intrinsic properties of adipose tissue depots, including developmental origin, adipogenic and proliferative capacity, glucose and lipid metabolism, hormonal control, thermogenic ability, and vascularization. In obesity, these depot-specific differences translate into specific fat distribution patterns, which are closely associated with differential cardiometabolic risks. The adventitial fat layer, also known as perivascular adipose tissue (PVAT), is of major importance. Similar to the visceral adipose tissue, PVAT has a pathophysiological role in CVDs. PVAT influences vascular homeostasis by releasing numerous vasoactive factors, cytokines, and adipokines, which can readily target the underlying smooth muscle cell layers, regulating the vascular tone, distribution of blood flow, as well as angiogenesis, inflammatory processes, and redox status. In this review, we summarize the current knowledge and discuss the role of PVAT within the scope of adipose tissue as a major contributing factor to obesity-associated cardiovascular risk. Relevant clinical studies documenting the relationship between PVAT dysfunction and CVD with a focus on potential mechanisms by which PVAT contributes to obesity-related CVDs are pointed out.

Pharmacokinetics and tissue distribution study of Praeruptorin D from Radix peucedani in rats by high-performance liquid chromatography (HPLC).

PubMed

Liang, Taigang; Yue, Wenyan; Du, Xue; Ren, Luhui; Li, Qingshan

2012-01-01

Praeruptorin D (PD), a major pyranocoumarin isolated from Radix Peucedani, exhibited antitumor and anti-inflammatory activities. The aim of this study was to investigate the pharmacokinetics and tissue distribution of PD in rats following intravenous (i.v.) administration. The levels of PD in plasma and tissues were measured by a simple and sensitive reversed-phase high-performance liquid chromatography (HPLC) method. The biosamples were treated by liquid-liquid extraction (LLE) with methyl tert-butyl ether (MTBE) and osthole was used as the internal standard (IS). The chromatographic separation was accomplished on a reversed-phase C(18) column using methanol-water (75:25, v/v) as mobile phase at a flow rate of 0.8 mL/min and ultraviolet detection wave length was set at 323 nm. The results demonstrate that this method has excellent specificity, linearity, precision, accuracy and recovery. The pharmacokinetic study found that PD fitted well into a two-compartment model with a fast distribution phase and a relative slow elimination phase. Tissue distribution showed that the highest concentration was observed in the lung, followed by heart, liver and kidney. Furthermore, PD can also be detected in the brain, which indicated that PD could cross the blood-brain barrier after i.v. administration.

Algorithms and Results of Eye Tissues Differentiation Based on RF Ultrasound

PubMed Central

Jurkonis, R.; Janušauskas, A.; Marozas, V.; Jegelevičius, D.; Daukantas, S.; Patašius, M.; Paunksnis, A.; Lukoševičius, A.

2012-01-01

Algorithms and software were developed for analysis of B-scan ultrasonic signals acquired from commercial diagnostic ultrasound system. The algorithms process raw ultrasonic signals in backscattered spectrum domain, which is obtained using two time-frequency methods: short-time Fourier and Hilbert-Huang transformations. The signals from selected regions of eye tissues are characterized by parameters: B-scan envelope amplitude, approximated spectral slope, approximated spectral intercept, mean instantaneous frequency, mean instantaneous bandwidth, and parameters of Nakagami distribution characterizing Hilbert-Huang transformation output. The backscattered ultrasound signal parameters characterizing intraocular and orbit tissues were processed by decision tree data mining algorithm. The pilot trial proved that applied methods are able to correctly classify signals from corpus vitreum blood, extraocular muscle, and orbit tissues. In 26 cases of ocular tissues classification, one error occurred, when tissues were classified into classes of corpus vitreum blood, extraocular muscle, and orbit tissue. In this pilot classification parameters of spectral intercept and Nakagami parameter for instantaneous frequencies distribution of the 1st intrinsic mode function were found specific for corpus vitreum blood, orbit and extraocular muscle tissues. We conclude that ultrasound data should be further collected in clinical database to establish background for decision support system for ocular tissue noninvasive differentiation. PMID:22654643

Monoclonal Antibodies against the Drosophila Nervous System

NASA Astrophysics Data System (ADS)

Fujita, Shinobu C.; Zipursky, Stephen L.; Benzer, Seymour; Ferrus, Alberto; Shotwell, Sandra L.

1982-12-01

A panel of 148 monoclonal antibodies directed against Drosophila neural antigens has been prepared by using mice immunized with homogenates of Drosophila tissue. Antibodies were screened immunohistochemically on cryostat sections of fly heads. A large diversity of staining patterns was observed. Some antigens were broadly distributed among tissues; others were highly specific to nerve fibers, neuropil, muscle, the tracheal system, cell nuclei, photoreceptors, or other structures. The antigens for many of the antibodies have been identified on immunoblots. Monoclonal antibodies that identify specific molecules within the nervous system should prove useful in the study of the molecular genetics of neural development.

Obtaining source current density related to irregularly structured electromagnetic target field inside human body using hybrid inverse/FDTD method.

PubMed

Han, Jijun; Yang, Deqiang; Sun, Houjun; Xin, Sherman Xuegang

2017-01-01

Inverse method is inherently suitable for calculating the distribution of source current density related with an irregularly structured electromagnetic target field. However, the present form of inverse method cannot calculate complex field-tissue interactions. A novel hybrid inverse/finite-difference time domain (FDTD) method that can calculate the complex field-tissue interactions for the inverse design of source current density related with an irregularly structured electromagnetic target field is proposed. A Huygens' equivalent surface is established as a bridge to combine the inverse and FDTD method. Distribution of the radiofrequency (RF) magnetic field on the Huygens' equivalent surface is obtained using the FDTD method by considering the complex field-tissue interactions within the human body model. The obtained magnetic field distributed on the Huygens' equivalent surface is regarded as the next target. The current density on the designated source surface is derived using the inverse method. The homogeneity of target magnetic field and specific energy absorption rate are calculated to verify the proposed method.

In silico identification and comparative analysis of differentially expressed genes in human and mouse tissues

PubMed Central

Pao, Sheng-Ying; Lin, Win-Li; Hwang, Ming-Jing

2006-01-01

Background Screening for differentially expressed genes on the genomic scale and comparative analysis of the expression profiles of orthologous genes between species to study gene function and regulation are becoming increasingly feasible. Expressed sequence tags (ESTs) are an excellent source of data for such studies using bioinformatic approaches because of the rich libraries and tremendous amount of data now available in the public domain. However, any large-scale EST-based bioinformatics analysis must deal with the heterogeneous, and often ambiguous, tissue and organ terms used to describe EST libraries. Results To deal with the issue of tissue source, in this work, we carefully screened and organized more than 8 million human and mouse ESTs into 157 human and 108 mouse tissue/organ categories, to which we applied an established statistic test using different thresholds of the p value to identify genes differentially expressed in different tissues. Further analysis of the tissue distribution and level of expression of human and mouse orthologous genes showed that tissue-specific orthologs tended to have more similar expression patterns than those lacking significant tissue specificity. On the other hand, a number of orthologs were found to have significant disparity in their expression profiles, hinting at novel functions, divergent regulation, or new ortholog relationships. Conclusion Comprehensive statistics on the tissue-specific expression of human and mouse genes were obtained in this very large-scale, EST-based analysis. These statistical results have been organized into a database, freely accessible at our website , for easy searching of human and mouse tissue-specific genes and for investigating gene expression profiles in the context of comparative genomics. Comparative analysis showed that, although highly tissue-specific genes tend to exhibit similar expression profiles in human and mouse, there are significant exceptions, indicating that orthologous genes, while sharing basic genomic properties, could result in distinct phenotypes. PMID:16626500

Effects of Fiber Type and Size on the Heterogeneity of Oxygen Distribution in Exercising Skeletal Muscle

PubMed Central

Liu, Gang; Mac Gabhann, Feilim; Popel, Aleksander S.

2012-01-01

The process of oxygen delivery from capillary to muscle fiber is essential for a tissue with variable oxygen demand, such as skeletal muscle. Oxygen distribution in exercising skeletal muscle is regulated by convective oxygen transport in the blood vessels, oxygen diffusion and consumption in the tissue. Spatial heterogeneities in oxygen supply, such as microvascular architecture and hemodynamic variables, had been observed experimentally and their marked effects on oxygen exchange had been confirmed using mathematical models. In this study, we investigate the effects of heterogeneities in oxygen demand on tissue oxygenation distribution using a multiscale oxygen transport model. Muscles are composed of different ratios of the various fiber types. Each fiber type has characteristic values of several parameters, including fiber size, oxygen consumption, myoglobin concentration, and oxygen diffusivity. Using experimentally measured parameters for different fiber types and applying them to the rat extensor digitorum longus muscle, we evaluated the effects of heterogeneous fiber size and fiber type properties on the oxygen distribution profile. Our simulation results suggest a marked increase in spatial heterogeneity of oxygen due to fiber size distribution in a mixed muscle. Our simulations also suggest that the combined effects of fiber type properties, except size, do not contribute significantly to the tissue oxygen spatial heterogeneity. However, the incorporation of the difference in oxygen consumption rates of different fiber types alone causes higher oxygen heterogeneity compared to control cases with uniform fiber properties. In contrast, incorporating variation in other fiber type-specific properties, such as myoglobin concentration, causes little change in spatial tissue oxygenation profiles. PMID:23028531

Distribution volumes of macromolecules in human ovarian and endometrial cancers--effects of extracellular matrix structure.

PubMed

Haslene-Hox, Hanne; Oveland, Eystein; Woie, Kathrine; Salvesen, Helga B; Tenstad, Olav; Wiig, Helge

2015-01-01

Elements of the extracellular matrix (ECM), notably collagen and glucosaminoglycans, will restrict part of the space available for soluble macromolecules simply because the molecules cannot occupy the same space. This phenomenon may influence macromolecular drug uptake. To study the influence of steric and charge effects of the ECM on the distribution volumes of macromolecules in human healthy and malignant gynecologic tissues we used as probes 15 abundant plasma proteins quantified by high-resolution mass spectrometry. The available distribution volume (VA) of albumin was increased in ovarian carcinoma compared with healthy ovarian tissue. Furthermore, VA of plasma proteins between 40 and 190 kDa decreased with size for endometrial carcinoma and healthy ovarian tissue, but was independent of molecular weight for the ovarian carcinomas. An effect of charge on distribution volume was only found in healthy ovaries, which had lower hydration and high collagen content, indicating that a condensed interstitium increases the influence of negative charges. A number of earlier suggested biomarker candidates were detected in increased amounts in malignant tissue, e.g., stathmin and spindlin-1, showing that interstitial fluid, even when unfractionated, can be a valuable source for tissue-specific proteins. We demonstrate that the distribution of abundant plasma proteins in the interstitium can be elucidated by mass spectrometry methods and depends markedly on hydration and ECM structure. Our data can be used in modeling of drug uptake, and give indications on ECM components to be targeted to increase the uptake of macromolecular substances. Copyright © 2015 the American Physiological Society.

Studies of nontarget-mediated distribution of human full-length IgG1 antibody and its FAb fragment in cardiovascular and metabolic-related tissues.

PubMed

Davidsson, Pia; Söderling, Ann-Sofi; Svensson, Lena; Ahnmark, Andrea; Flodin, Christine; Wanag, Ewa; Screpanti-Sundqvist, Valentina; Gennemark, Peter

2015-05-01

Tissue distribution and pharmacokinetics (PK) of full-length nontargeted antibody and its antigen-binding fragment (FAb) were evaluated for a range of tissues primarily of interest for cardiovascular and metabolic diseases. Mice were intravenously injected with a dose of 10 mg/kg of either human IgG1or its FAb fragment; perfused tissues were collected at a range of time points over 3 weeks for the human IgG1 antibody and 1 week for the human FAb antibody. Tissues were homogenized and antibody concentrations were measured by specific immunoassays on the Gyros system. Exposure in terms of maximum concentration (Cmax ) and area under the curve was assessed for all nine tissues. Tissue exposure of full-length antibody relative to plasma exposure was found to be between 1% and 10%, except for brain (0.2%). Relative concentrations of FAb antibody were the same, except for kidney tissue, where the antibody concentration was found to be ten times higher than in plasma. However, the absolute tissue uptake of full-length IgG was significantly higher than the absolute tissue uptake of the FAb antibody. This study provides a reference PK state for full-length whole and FAb antibodies in tissues related to cardiovascular and metabolic diseases that do not include antigen or antibody binding. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

DNA entropy reveals a significant difference in complexity between housekeeping and tissue specific gene promoters.

PubMed

Thomas, David; Finan, Chris; Newport, Melanie J; Jones, Susan

2015-10-01

The complexity of DNA can be quantified using estimates of entropy. Variation in DNA complexity is expected between the promoters of genes with different transcriptional mechanisms; namely housekeeping (HK) and tissue specific (TS). The former are transcribed constitutively to maintain general cellular functions, and the latter are transcribed in restricted tissue and cells types for specific molecular events. It is known that promoter features in the human genome are related to tissue specificity, but this has been difficult to quantify on a genomic scale. If entropy effectively quantifies DNA complexity, calculating the entropies of HK and TS gene promoters as profiles may reveal significant differences. Entropy profiles were calculated for a total dataset of 12,003 human gene promoters and for 501 housekeeping (HK) and 587 tissue specific (TS) human gene promoters. The mean profiles show the TS promoters have a significantly lower entropy (p<2.2e-16) than HK gene promoters. The entropy distributions for the 3 datasets show that promoter entropies could be used to identify novel HK genes. Functional features comprise DNA sequence patterns that are non-random and hence they have lower entropies. The lower entropy of TS gene promoters can be explained by a higher density of positive and negative regulatory elements, required for genes with complex spatial and temporary expression. Copyright © 2015 Elsevier Ltd. All rights reserved.

Immunohistochemical and histomorphometric evaluation of vascular distribution in intact canine cranial cruciate ligament.

PubMed

Hayashi, Kei; Bhandal, Jitender; Kim, Sun Young; Rodriguez, Carlos O; Entwistle, Rachel; Naydan, Diane; Kapatkin, Amy; Stover, Susan M

2011-02-01

To (1) describe vascular distribution in the grossly intact canine cranial cruciate ligament (CCL) using immunohistochemical techniques specific to 2 components of blood vessels (factor VIII for endothelial cells, laminin for basement membrane); and (2) compare the vascularity in different areas of interest (craniomedial versus caudolateral bands; core versus epiligamentous regions; and proximal versus middle versus distal portions) in the intact normal canine CCL. In vitro study. Large, mature dogs (n=7) of breeds prone to CCL disease that were euthanatized for nonorthopedic conditions. Intact CCL were collected from fresh canine cadavers free from stifle pathology. CCL tissue was processed for immunohistochemistry and stained for factor VIII and laminin. Vascular density was determined by histomorphometric analysis. Specific vascular staining was sparsely identified throughout the CCL; however, the proximal portion of the CCL appears to have a greater number of vessels than the middle or distal portion of the ligament. The CCL is a hypovascular tissue and its vascular distribution is not homogeneous. © Copyright 2010 by The American College of Veterinary Surgeons.

Mass Spectrometry Imaging, an Emerging Technology in Neuropsychopharmacology

PubMed Central

Shariatgorji, Mohammadreza; Svenningsson, Per; Andrén, Per E

2014-01-01

Mass spectrometry imaging is a powerful tool for directly determining the distribution of proteins, peptides, lipids, neurotransmitters, metabolites and drugs in neural tissue sections in situ. Molecule-specific imaging can be achieved using various ionization techniques that are suited to different applications but which all yield data with high mass accuracies and spatial resolutions. The ability to simultaneously obtain images showing the distributions of chemical species ranging from metal ions to macromolecules makes it possible to explore the chemical organization of a sample and to correlate the results obtained with specific anatomical features. The imaging of biomolecules has provided new insights into multiple neurological diseases, including Parkinson's and Alzheimer's disease. Mass spectrometry imaging can also be used in conjunction with other imaging techniques in order to identify correlations between changes in the distribution of important chemical species and other changes in the properties of the tissue. Here we review the applications of mass spectrometry imaging in neuroscience research and discuss its potential. The results presented demonstrate that mass spectrometry imaging is a useful experimental method with diverse applications in neuroscience. PMID:23966069

Mass spectrometry imaging, an emerging technology in neuropsychopharmacology.

PubMed

Shariatgorji, Mohammadreza; Svenningsson, Per; Andrén, Per E

2014-01-01

Mass spectrometry imaging is a powerful tool for directly determining the distribution of proteins, peptides, lipids, neurotransmitters, metabolites and drugs in neural tissue sections in situ. Molecule-specific imaging can be achieved using various ionization techniques that are suited to different applications but which all yield data with high mass accuracies and spatial resolutions. The ability to simultaneously obtain images showing the distributions of chemical species ranging from metal ions to macromolecules makes it possible to explore the chemical organization of a sample and to correlate the results obtained with specific anatomical features. The imaging of biomolecules has provided new insights into multiple neurological diseases, including Parkinson's and Alzheimer's disease. Mass spectrometry imaging can also be used in conjunction with other imaging techniques in order to identify correlations between changes in the distribution of important chemical species and other changes in the properties of the tissue. Here we review the applications of mass spectrometry imaging in neuroscience research and discuss its potential. The results presented demonstrate that mass spectrometry imaging is a useful experimental method with diverse applications in neuroscience.

The GmFAD7 gene family from soybean: identification of novel genes and tissue-specific conformations of the FAD7 enzyme involved in desaturase activity.

PubMed

Andreu, Vanesa; Lagunas, Beatriz; Collados, Raquel; Picorel, Rafael; Alfonso, Miguel

2010-07-01

The FAD7 gene encodes a omega3 fatty acid desaturase which catalyses the production of trienoic fatty acids (TAs) in plant chloroplasts. A novel GmFAD7 gene (named GmFAD7-2) has been identified in soybean, with high homology to the previously annotated GmFAD7 gene. Genomic sequencing analysis together with searches at the soybean genome database further confirmed that both GmFAD7 genes were located in two different loci within the soybean genome, suggesting that the soybean omega3 plastidial desaturase FAD7 is encoded by two different paralogous genes. Both GmFAD7-1 and GmFAD7-2 genes were expressed in all soybean tissues examined, displaying their highest mRNA accumulation in leaves. This expression profile contrasted with GmFAD3A and GmFAD3B mRNA accumulation, which was very low in this tissue. These results suggested a concerted control of plastidial and reticular omega3 desaturase gene expression in soybean mature leaves. Analysis of GmFAD7 protein distribution in different soybean tissues showed that, in mature leaves, two bands were detected, coincident with the higher expression level of both GmFAD7 genes and the highest 18:3 fatty acid accumulation. By contrast, in seeds, where FAD7 activity is low, specific GmFAD7 protein conformations were observed. These GmFAD7 protein conformations were affected in vitro by changes in the redox conditions of thiol groups and iron availability. These results suggest the existence of tissue-specific post-translational regulatory mechanisms affecting the distribution and conformation of the FAD7 enzymes related with the control of its activity.

[Distributions of H3K27me3 and its modification enzymes in different tissues of mice].

PubMed

Wang, Yuying; Wang, Xinli; Zhang, Ran; Zhang, Zhiyan; Wang, Yu; Yang, Bo; Wang, Guanjie; Zhang, Xin; Ma, Fuhao; Xu, Hongye; Wu, Xiaohui; Zhang, Feng; Li, Qing

2017-11-01

Objective To investigate the levels of trimethylated histone 3 at lysine residue 27 (H3K27me3) and its modification enzymes Zeste gene enhancer homolog 2 (EZH2), lysine-specific demethylase 6B (Kdm6B/JMJD3) and lysine-specific demethylase 6A (Kdm6A/UTX) in tissues and organs of 7-day and 2-month postnatal mice. Methods Immunohistochemistry was used to detect the expressions of H3K27me3 and its modification enzymes EZH2, JMJD3 and UTX in the brain, salivary glands, back fat, thymus, lung, heart, stomach, intestines, liver, testes, and skin of 7-day and 2-month mice. Real-time quantitative PCR was used to confirm the results. The relationships between H3K27me3 and its modification enzymes were analyzed statistically. Results Immunohistochemistry showed H3K27me3 persistently present in all examined tissues of 7-day and 2-month mice. EZH2 was persistently expressed in the brain, heart, liver, and skin of 7-day and 2-month mice, but only expressed in the salivary glands, adipose tissues, thymus, lung, intestines, and testes of 2-month mice. JMJD3 was expressed in the brain, salivary glands, adipose tissues, lung, heart, stomach, intestines, testes, skin of 7-day mice, but was not expressed in the lung, adipose tissues and stomach of 2-month mice. UTX was expressed in the brain, salivary glands, adipose tissues, lung, heart, testes, skin of 7-day mice, but only expressed in the testes of 2-month mice. Most mRNA of H3K27 modification enzymes were moderately or highly expressed as their immunohistochemical results were positive. Conclusion There was H3K27me3 persistently present in the all examined tissues at different stages. EZH2 was mostly expressed in the brain, salivary glands, adipose tissues, thymus, lung, heart, intestines, liver, testes and skin of 2-month-old mice. JMJD3 and UTX were mostly expressed in the brain, salivary glands, adipose tissues, lung, heart, skin and testes of 7-day-old mice. No significant association was found between the distribution of H3K27me3 and the expression of EZH2. There was also no obvious inverse distribution relationship between H3K27me3 and JMJD3 or UTX. Moreover, there was no negative relationship between the distribution of EZH2, JMJD3 and UTX. These results suggest that EZH2, JMJD3 and UTX may play important roles in many tissues of mice after birth. The levels of H3K27me3 and its modified enzymes may be controlled by multiple factors in vivo to fulfill complex physiological functions.

Tissue- and cell-specific localization of galectins, β-galactose-binding animal lectins, and their potential functions in health and disease.

PubMed

Nio-Kobayashi, Junko

2017-01-01

Fifteen galectins, β-galactose-binding animal lectins, are known to be distributed throughout the body. We herein summarize current knowledge on the tissue- and cell-specific localization of galectins and their potential functions in health and disease. Galectin-3 is widely distributed in epithelia, including the simple columnar epithelium in the gut, stratified squamous epithelium in the gut and skin, and transitional epithelium and several regions in nephrons in the urinary tract. Galectin-2 and galectin-4/6 are gut-specific, while galectin-7 is found in the stratified squamous epithelium in the gut and skin. The reproductive tract mainly contains galectin-1 and galectin-3, and their expression markedly changes during the estrous/menstrual cycle. The galectin subtype expressed in the corpus luteum (CL) changes in association with luteal function. The CL of women and cows displays a "galectin switch" with coordinated changes in the major galectin subtype and its ligand glycoconjugate structure. Macrophages express galectin-3, which may be involved in phagocytotic activity. Lymphoid tissues contain galectin-3-positive macrophages, which are not always stained with the macrophage marker, F4/80. Subsets of neurons in the brain and dorsal root ganglion express galectin-1 and galectin-3, which may contribute to the regeneration of damaged axons, stem cell differentiation, and pain control. The subtype-specific contribution of galectins to implantation, fibrosis, and diabetes are also discussed. The function of galectins may differ depending on the tissues or cells in which they act. The ligand glycoconjugate structures mediated by glycosyltransferases including MGAT5, ST6GAL1, and C2GnT are important for revealing the functions of galectins in healthy and disease states.

Dynamic biochemical tissue analysis detects functional L-selectin ligands on colon cancer tissues

PubMed Central

Carlson, Grady E.; Martin, Eric W.; Shirure, Venktesh S.; Malgor, Ramiro; Resto, Vicente A.; Goetz, Douglas J.; Burdick, Monica M.

2017-01-01

A growing body of evidence suggests that L-selectin ligands presented on circulating tumor cells facilitate metastasis by binding L-selectin presented on leukocytes. Commonly used methods for detecting L-selectin ligands on tissues, e.g., immunostaining, are performed under static, no-flow conditions. However, such analysis does not assay for functional L-selectin ligands, specifically those ligands that promote adhesion under shear flow conditions. Recently our lab developed a method, termed dynamic biochemical tissue analysis (DBTA), to detect functional selectin ligands in situ by probing tissues with L-selectin-coated microspheres under hemodynamic flow conditions. In this investigation, DBTA was used to probe human colon tissues for L-selectin ligand activity. The detection of L-selectin ligands using DBTA was highly specific. Furthermore, DBTA reproducibly detected functional L-selectin ligands on diseased, e.g., cancerous or inflamed, tissues but not on noncancerous tissues. In addition, DBTA revealed a heterogeneous distribution of functional L-selectin ligands on colon cancer tissues. Most notably, detection of L-selectin ligands by immunostaining using HECA-452 antibody only partially correlated with functional L-selectin ligands detected by DBTA. In summation, the results of this study demonstrate that DBTA detects functional selectin ligands to provide a unique characterization of pathological tissue. PMID:28282455

Dynamic biochemical tissue analysis detects functional L-selectin ligands on colon cancer tissues.

PubMed

Carlson, Grady E; Martin, Eric W; Shirure, Venktesh S; Malgor, Ramiro; Resto, Vicente A; Goetz, Douglas J; Burdick, Monica M

2017-01-01

A growing body of evidence suggests that L-selectin ligands presented on circulating tumor cells facilitate metastasis by binding L-selectin presented on leukocytes. Commonly used methods for detecting L-selectin ligands on tissues, e.g., immunostaining, are performed under static, no-flow conditions. However, such analysis does not assay for functional L-selectin ligands, specifically those ligands that promote adhesion under shear flow conditions. Recently our lab developed a method, termed dynamic biochemical tissue analysis (DBTA), to detect functional selectin ligands in situ by probing tissues with L-selectin-coated microspheres under hemodynamic flow conditions. In this investigation, DBTA was used to probe human colon tissues for L-selectin ligand activity. The detection of L-selectin ligands using DBTA was highly specific. Furthermore, DBTA reproducibly detected functional L-selectin ligands on diseased, e.g., cancerous or inflamed, tissues but not on noncancerous tissues. In addition, DBTA revealed a heterogeneous distribution of functional L-selectin ligands on colon cancer tissues. Most notably, detection of L-selectin ligands by immunostaining using HECA-452 antibody only partially correlated with functional L-selectin ligands detected by DBTA. In summation, the results of this study demonstrate that DBTA detects functional selectin ligands to provide a unique characterization of pathological tissue.

Theoretical analysis, design and development of a 27-MHz folded loop antenna as a potential applicator in hyperthermia treatment.

PubMed

Kouloulias, Vassilis; Karanasiou, Irene; Giamalaki, Melina; Matsopoulos, George; Kouvaris, John; Kelekis, Nikolaos; Uzunoglu, Nikolaos

2015-02-01

A hyperthermia system using a folded loop antenna applicator at 27 MHz for soft tissue treatment was investigated both theoretically and experimentally to evaluate its clinical value. The electromagnetic analysis of a 27-MHz folded loop antenna for use in human tissue was based on a customised software tool and led to the design and development of the proposed hyperthermia system. The system was experimentally validated using specific absorption rate (SAR) distribution estimations through temperature distribution measurements of a muscle tissue phantom after electromagnetic exposure. Various scenarios for optimal antenna positioning were also performed. Comparison of the theoretical and experimental analysis results shows satisfactory agreement. The SAR level of 50% reaches 8 cm depth in the tissue phantom. Thus, based on the maximum observed SAR values that were of the order of 100 W/kg, the antenna specified is suitable for deep tumour heating. Theoretical and experimental SAR distribution results as derived from this study are in agreement. The proposed folded loop antenna seems appropriate for use in hyperthermia treatment, achieving proper planning and local treatment of deeply seated affected areas and lesions.

Relation between lineal energy distribution and relative biological effectiveness for photon beams according to the microdosimetric kinetic model.

PubMed

Okamoto, Hiroyuki; Kanai, Tatsuaki; Kase, Yuki; Matsumoto, Yoshitaka; Furusawa, Yoshiya; Fujita, Yukio; Saitoh, Hidetoshi; Itami, Jun; Kohno, Toshiyuki

2011-01-01

Our cell survival data showed the obvious dependence of RBE on photon energy: The RBE value for 200 kV X-rays was approximately 10% greater than those for mega-voltage photon beams. In radiation therapy using mega-voltage photon beams, the photon energy distribution outside the field is different with that in the radiation field because of a large number of low energy scattering photons. Hence, the RBE values outside the field become greater. To evaluate the increase in RBE, the method of deriving the RBE using the Microdosimetric Kinetic model (MK model) was proposed in this study. The MK model has two kinds of the parameters, tissue-specific parameters and the dose-mean lineal energy derived from the lineal energy distributions measured with a Tissue-Equivalent Proportional Counter (TEPC). The lineal energy distributions with the same geometries of the cell irradiations for 200 kV X-rays, (60)Co γ-rays, and 6 MV X-rays were obtained with the TEPC and Monte Carlo code GEANT4. The measured lineal energy distribution for 200 kV X-rays was quite different from those for mega-voltage photon beams. The dose-mean lineal energy of 200 kV X-rays showed the greatest value, 4.51 keV/µm, comparing with 2.34 and 2.36 keV/µm for (60)Co γ-rays and 6 MV X-rays, respectively. By using the results of the TEPC and cell irradiations, the tissue-specific parameters in the MK model were determined. As a result, the RBE of the photon beams (y(D): 2~5 keV/µm) in arbitrary conditions can be derived by the measurements only or the calculations only of the dose-mean lineal energy.

Tissue-specific distributions of inorganic arsenic and its methylated metabolites, especially in cerebral cortex, cerebellum and hippocampus of mice after a single oral administration of arsenite.

PubMed

Li, Jinlong; Duan, Xiaoxu; Dong, Dandan; Zhang, Yang; Zhao, Lu; Li, Wei; Chen, Jinli; Sun, Guifan; Li, Bing

2017-09-01

Groundwater contaminated with inorganic arsenic (iAs) is the main source of human exposure to arsenic and generates a global health issue. In this study, the urinary excretion, as well as the time-course distributions of various arsenic species in murine tissues, especially in different brain regions were determined after a single oral administration of 2.5, 5, 10 and 20mg/kg sodium arsenite (NaAsO 2 ). Our data showed that the peak times of urinary, hepatic and nephritic total arsenic (TAs) were happened at about 1h, then TAs levels decreased gradually and almost could not be observed after 72h. On contrast, the time course of TAs in lung, urinary bladder and different brain regions exhibited an obvious process of accumulation and elimination,and the peak times were nearly at 6h to 9h. TAs levels of 10 and 20mg/kg NaAsO 2 groups were significantly higher than 2.5 and 5mg/kg groups, and the amounts of TAs in 5mg/kg groups were in the order of liver>lung>kidney>urinary bladder>hippocampus>cerebral cortex>cerebellum. In addition, iAs was the most abundant species in liver and kidney, while lung and urinary bladder accumulated the highest concentrations of dimethylated arsenicals (DMA). What's more, the distributions of arsenic species were not homogeneous among different brain regions, as DMA was the sole species in cerebral cortex and cerebellum, while extremely high concentrations and percentages of monomethylated arsenicals (MMA) were found in hippocampus. These results demonstrated that distributions of iAs and its methylated metabolites were tissue-specific and even not homogeneous among different brain regions, which must be considered as to the tissue- and region-specific toxicity of iAs exposure. Our results thus provide useful information for clarifying and reducing the uncertainty in the risk assessment for this metalloid. Copyright © 2016 Elsevier GmbH. All rights reserved.

Detection of Hepatitis B and C Viruses in Almost All Hepatocytes by Modified PCR-Based In Situ Hybridization▿

PubMed Central

Nuriya, Hideko; Inoue, Kazuaki; Tanaka, Takeshi; Hayashi, Yukiko; Hishima, Tsunekazu; Funata, Nobuaki; Kaji, Kyosuke; Hayashi, Seishu; Kaneko, Shuichi; Kohara, Michinori

2010-01-01

Although PCR-based in situ hybridization (PCR-ISH) can be used to determine the distribution and localization of pathogens in tissues, this approach is hampered by its low specificity. Therefore, we used a highly specific and sensitive PCR-ISH method to reveal the lobular distribution and intracellular localization of hepatitis B virus (HBV) and HCV in chronic liver disease and to clarify the state of persistent HBV and HCV infection in the liver. HBV genomic DNA was detected in almost all hepatocytes, whereas HBV RNA or protein was differentially distributed only in a subset of the HBV DNA-positive region. Further, HCV genomic RNA was detected in almost all hepatocytes and was localized to the cytoplasm. HCV RNA was also detected in the epithelium of the large bile duct but not in endothelial cells, portal tracts, or sinusoidal lymphocytes. In patients with HBV and HCV coinfection, HCV RNA was localized to the noncancerous tissue, whereas HBV DNA was found only in the cancerous tissue. Using this novel PCR-ISH method, we could visualize the staining pattern of HBV and HCV in liver sections, and we obtained results consistent with those of real-time detection (RTD)-PCR analysis. In conclusion, almost all hepatocytes are infected with HBV or HCV in chronic liver disease; this finding implies that the viruses spreads throughout the liver in the chronic stage. PMID:20739486

Intramyocardial Injection of siRNAs Can Efficiently Establish Myocardial Tissue-Specific Renalase Knockdown Mouse Model.

PubMed

Huang, Kun; Liu, Ju; Zhang, Hui; Wang, Jiliang; Li, Huili

2016-01-01

Ischaemia/reperfusion (I/R) injury will cause additional death of cardiomyocytes in ischaemic heart disease. Recent studies revealed that renalase was involved in the I/R injury. So, the myocardial tissue-specific knockdown mouse models were needed for the investigations of renalase. To establish the mouse models, intramyocardial injection of siRNAs targeting renalase was performed in mice. The wild distribution and high transfection efficiency of the siRNAs were approved. And the renalase expression was efficiently suppressed in myocardial tissue. Compared with the high cost, time consumption, and genetic compensation risk of the Cre/loxP technology, RNA interference (RNAi) technology is much cheaper and less time-consuming. Among the RNAi technologies, injection of siRNAs is safer than virus. And considering the properties of the I/R injury mouse models, the efficiency and durability of injection with siRNAs are acceptable for the studies. Altogether, intramyocardial injection of siRNAs targeting renalase is an economical, safe, and efficient method to establish myocardial tissue-specific renalase knockdown mouse models.

Flux analysis of cholesterol biosynthesis in vivo reveals multiple tissue and cell-type specific pathways

PubMed Central

Mitsche, Matthew A; McDonald, Jeffrey G; Hobbs, Helen H; Cohen, Jonathan C

2015-01-01

Two parallel pathways produce cholesterol: the Bloch and Kandutsch-Russell pathways. Here we used stable isotope labeling and isotopomer analysis to trace sterol flux through the two pathways in mice. Surprisingly, no tissue used the canonical K–R pathway. Rather, a hybrid pathway was identified that we call the modified K–R (MK–R) pathway. Proportional flux through the Bloch pathway varied from 8% in preputial gland to 97% in testes, and the tissue-specificity observed in vivo was retained in cultured cells. The distribution of sterol isotopomers in plasma mirrored that of liver. Sterol depletion in cultured cells increased flux through the Bloch pathway, whereas overexpression of 24-dehydrocholesterol reductase (DHCR24) enhanced usage of the MK–R pathway. Thus, relative use of the Bloch and MK–R pathways is highly variable, tissue-specific, flux dependent, and epigenetically fixed. Maintenance of two interdigitated pathways permits production of diverse bioactive sterols that can be regulated independently of cholesterol. DOI: http://dx.doi.org/10.7554/eLife.07999.001 PMID:26114596

Thermal effects in tissues induced by interstitial irradiation of near infrared laser with a cylindrical diffuser

NASA Astrophysics Data System (ADS)

Le, Kelvin; Johsi, Chet; Figueroa, Daniel; Goddard, Jessica; Li, Xiaosong; Towner, Rheal A.; Saunders, Debra; Smith, Nataliya; Liu, Hong; Hode, Tomas; Nordquist, Robert E.; Chen, Wei R.

2011-03-01

Laser immunotherapy (LIT), using non-invasive laser irradiation, has resulted in promising outcomes in the treatment of late-stage cancer patients. However, the tissue absorption of laser light limits the clinical applications of LIT in patients with dark skin, or with deep tumors. The present study is designed to investigate the thermal effects of interstitial irradiation using an 805-nm laser with a cylindrical diffuser, in order to overcome the limitations of the non-invasive mode of treatment. Cow liver and rat tumors were irradiated using interstitial fiber. The temperature increase was monitored by thermocouples that were inserted into the tissue at different sites around the cylinder fiber. Three-dimensional temperature distribution in target tissues during and after interstitial laser irradiation was also determined by Proton Resonance Frequency. The preliminary results showed that the output power of laser and the optical parameters of the target tissue determined the light distribution in the tissue. The temperature distributions varied in the tissue according to the locations relative to the active tip of the cylindrical diffuser. The temperature increase is strongly related to the laser power and irradiation time. Our results using thermocouples and optical sensors indicated that the PRF method is reliable and accurate for temperature determination. Although the inhomogeneous biological tissues could result in temperature fluctuation, the temperature trend still can be reliable enough for the guidance of interstitial irradiation. While this study provides temperature profiles in tumor tissue during interstitial irradiation, the biological effects of the irradiation remain unclear. Future studies will be needed, particularly in combination with the application of immunostimulant for inducing tumor-specific immune responses in the treatment of metastatic tumors.

A new graphic plot analysis for determination of neuroreceptor binding in positron emission tomography studies.

PubMed

Ito, Hiroshi; Yokoi, Takashi; Ikoma, Yoko; Shidahara, Miho; Seki, Chie; Naganawa, Mika; Takahashi, Hidehiko; Takano, Harumasa; Kimura, Yuichi; Ichise, Masanori; Suhara, Tetsuya

2010-01-01

In positron emission tomography (PET) studies with radioligands for neuroreceptors, tracer kinetics have been described by the standard two-tissue compartment model that includes the compartments of nondisplaceable binding and specific binding to receptors. In the present study, we have developed a new graphic plot analysis to determine the total distribution volume (V(T)) and nondisplaceable distribution volume (V(ND)) independently, and therefore the binding potential (BP(ND)). In this plot, Y(t) is the ratio of brain tissue activity to time-integrated arterial input function, and X(t) is the ratio of time-integrated brain tissue activity to time-integrated arterial input function. The x-intercept of linear regression of the plots for early phase represents V(ND), and the x-intercept of linear regression of the plots for delayed phase after the equilibrium time represents V(T). BP(ND) can be calculated by BP(ND)=V(T)/V(ND)-1. Dynamic PET scanning with measurement of arterial input function was performed on six healthy men after intravenous rapid bolus injection of [(11)C]FLB457. The plot yielded a curve in regions with specific binding while it yielded a straight line through all plot data in regions with no specific binding. V(ND), V(T), and BP(ND) values calculated by the present method were in good agreement with those by conventional non-linear least-squares fitting procedure. This method can be used to distinguish graphically whether the radioligand binding includes specific binding or not.

Temperature-dependent thermal properties of ex vivo liver undergoing thermal ablation.

PubMed

Guntur, Sitaramanjaneya Reddy; Lee, Kang Il; Paeng, Dong-Guk; Coleman, Andrew John; Choi, Min Joo

2013-10-01

Thermotherapy uses a heat source that raises temperatures in the target tissue, and the temperature rise depends on the thermal properties of the tissue. Little is known about the temperature-dependent thermal properties of tissue, which prevents us from accurately predicting the temperature distribution of the target tissue undergoing thermotherapy. The present study reports the key thermal parameters (specific heat capacity, thermal conductivity and heat diffusivity) measured in ex vivo porcine liver while being heated from 20 ° C to 90 ° C and then naturally cooled down to 20 ° C. The study indicates that as the tissue was heated, all the thermal parameters resulted in plots with asymmetric quasi-parabolic curves with temperature, being convex downward with their minima at the turning temperature of 35-40 ° C. The largest change was observed for thermal conductivity, which decreased by 9.6% from its initial value (at 20 ° C) at the turning temperature (35 ° C) and rose by 45% at 90 ° C from its minimum (at 35 ° C). The minima were 3.567 mJ/(m(3) ∙ K) for specific heat capacity, 0.520 W/(m.K) for thermal conductivity and 0.141 mm(2)/s for thermal diffusivity. The minimum at the turning temperature was unique, and it is suggested that it be taken as a characteristic value of the thermal parameter of the tissue. On the other hand, the thermal parameters were insensitive to temperature and remained almost unchanged when the tissue cooled down, indicating that their variations with temperature were irreversible. The rate of the irreversible rise at 35 ° C was 18% in specific heat capacity, 40% in thermal conductivity and 38.3% in thermal diffusivity. The study indicates that the key thermal parameters of ex vivo porcine liver vary largely with temperature when heated, as described by asymmetric quasi-parabolic curves of the thermal parameters with temperature, and therefore, substantial influence on the temperature distribution of the tissue undergoing thermotherapy is expected. 2013. Published by Elsevier Inc

Predictive analysis of photodynamic therapy applied to esophagus cancer

NASA Astrophysics Data System (ADS)

Fanjul-Vélez, F.; del Campo-Gutiérrez, M.; Ortega-Quijano, N.; Arce-Diego, J. L.

2008-04-01

The use of optical techniques in medicine has revolutionized in many cases the medical praxis, providing new tools for practitioners or improving the existing ones in the fight against diseases. The application of this technology comprises mainly two branches, characterization and treatment of biological tissues. Photodynamic Therapy (PDT) provides a solution for malignant tissue destruction, by means of the inoculation of a photosensitizer and irradiation by an optical source. The key factor of the procedure is the localization of the damage to avoid collateral harmful effects. The volume of tissue destroyed depends on the type of photosensitizer inoculated, both on its reactive characteristics and its distribution inside the tissue, and also on the specific properties of the optical source, that is, the optical power, wavelength and exposition time. In this work, a model for PDT based on the one-dimensional diffusion equation, extensible to 3D, to estimate the optical distribution in tissue, and on photosensitizer parameters to take into account the photobleaching effect is proposed. The application to esophagus cancer allows the selection of the right optical source parameters, like irradiance, wavelength or exposition time, in order to predict the area of tissue destruction.

Evaluation of S-values and dose distributions for {sup 90}Y, {sup 131}I, {sup 166}Ho, and {sup 188}Re in seven lobes of the rat liver

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

Xie Tianwu; Liu Qian; Zaidi, Habib

2012-03-15

Purpose: Rats have been widely used in radionuclide therapy research for the treatment of hepatocellular carcinoma (HCC). This has created the need to assess rat liver absorbed radiation dose. In most dose estimation studies, the rat liver is considered as a homogeneous integrated target organ with a tissue composition assumed to be similar to that of human liver tissue. However, the rat liver is composed of several lobes having different anatomical and chemical characteristics. To assess the overall impact on rat liver dose calculation, the authors use a new voxel-based rat model with identified suborgan regions of the liver. Methods:more » The liver in the original cryosectional color images was manually segmented into seven individual lobes and subsequently integrated into a voxel-based computational rat model. Photon and electron particle transport was simulated using the MCNPX Monte Carlo code to calculate absorbed fractions and S-values for {sup 90}Y, {sup 131}I, {sup 166}Ho, and {sup 188}Re for the seven liver lobes. The effect of chemical composition on organ-specific absorbed dose was investigated by changing the chemical composition of the voxel filling liver material. Radionuclide-specific absorbed doses at the voxel level were further assessed for a small spherical hepatic tumor. Results: The self-absorbed dose for different liver lobes varied depending on their respective masses. A maximum difference of 3.5% was observed for the liver self-absorbed fraction between rat and human tissues for photon energies below 100 keV. {sup 166}Ho and {sup 188}Re produce a uniformly distributed high dose in the tumor and relatively low absorbed dose for surrounding tissues. Conclusions: The authors evaluated rat liver radiation doses from various radionuclides used in HCC treatments using a realistic computational rat model. This work contributes to a better understanding of all aspects influencing radiation transport in organ-specific radiation dose evaluation for preclinical therapy studies, from tissue composition to organ morphology and activity distribution.« less

Pharmacokinetic drivers of toxicity for basic molecules: Strategy to lower pKa results in decreased tissue exposure and toxicity for a small molecule Met inhibitor

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

Diaz, Dolores, E-mail: diaz.dolores@gene.com; Ford, Kevin A.; Hartley, Dylan P.

Several toxicities are clearly driven by free drug concentrations in plasma, such as toxicities related to on-target exaggerated pharmacology or off-target pharmacological activity associated with receptors, enzymes or ion channels. However, there are examples in which organ toxicities appear to correlate better with total drug concentrations in the target tissues, rather than with free drug concentrations in plasma. Here we present a case study in which a small molecule Met inhibitor, GEN-203, with significant liver and bone marrow toxicity in preclinical species was modified with the intention of increasing the safety margin. GEN-203 is a lipophilic weak base as demonstratedmore » by its physicochemical and structural properties: high LogD (distribution coefficient) (4.3) and high measured pKa (7.45) due to the basic amine (N-ethyl-3-fluoro-4-aminopiperidine). The physicochemical properties of GEN-203 were hypothesized to drive the high distribution of this compound to tissues as evidenced by a moderately-high volume of distribution (Vd > 3 l/kg) in mouse and subsequent toxicities of the compound. Specifically, the basicity of GEN-203 was decreased through addition of a second fluorine in the 3-position of the aminopiperidine to yield GEN-890 (N-ethyl-3,3-difluoro-4-aminopiperidine), which decreased the volume of distribution of the compound in mouse (Vd = 1.0 l/kg), decreased its tissue drug concentrations and led to decreased toxicity in mice. This strategy suggests that when toxicity is driven by tissue drug concentrations, optimization of the physicochemical parameters that drive tissue distribution can result in decreased drug concentrations in tissues, resulting in lower toxicity and improved safety margins. -- Highlights: ► Lower pKa for a small molecule: reduced tissue drug levels and toxicity. ► New analysis tools to assess electrostatic effects and ionization are presented. ► Chemical and PK drivers of toxicity can be leveraged to improve safety.« less

Tissue-specific autoregulation of Drosophila suppressor of forked by alternative poly(A) site utilization leads to accumulation of the suppressor of forked protein in mitotically active cells.

PubMed Central

Juge, F; Audibert, A; Benoit, B; Simonelig, M

2000-01-01

The Suppressor of forked protein is the Drosophila homolog of the 77K subunit of human cleavage stimulation factor, a complex required for the first step of the mRNA 3'-end-processing reaction. We have shown previously that wild-type su(f) function is required for the accumulation of a truncated su(f) transcript polyadenylated in intron 4 of the gene. This led us to propose a model in which the Su(f) protein would negatively regulate its own accumulation by stimulating 3'-end formation of this truncated su(f) RNA. In this article, we demonstrate this model and show that su(f) autoregulation is tissue specific. The Su(f) protein accumulates at a high level in dividing tissues, but not in nondividing tissues. We show that this distribution of the Su(f) protein results from stimulation by Su(f) of the tissue-specific utilization of the su(f) intronic poly(A) site, leading to the accumulation of the truncated su(f) transcript in nondividing tissues. Utilization of this intronic poly(A) site is affected in a su(f) mutant and restored in the mutant with a transgene encoding wild-type Su(f) protein. These data provide an in vivo example of cell-type-specific regulation of a protein level by poly(A) site choice, and confirm the role of Su(f) in regulation of poly(A) site utilization. PMID:11105753

Small and intermediate conductance Ca(2+)-activated K+ channels confer distinctive patterns of distribution in human tissues and differential cellular localisation in the colon and corpus cavernosum.

PubMed

Chen, Mao Xiang; Gorman, Shelby A; Benson, Bill; Singh, Kuljit; Hieble, J Paul; Michel, Martin C; Tate, Simon N; Trezise, Derek J

2004-06-01

The SK/IK family of small and intermediate conductance calcium-activated potassium channels contains four members, SK1, SK2, SK3 and IK1, and is important for the regulation of a variety of neuronal and non-neuronal functions. In this study we have analysed the distribution of these channels in human tissues and their cellular localisation in samples of colon and corpus cavernosum. SK1 mRNA was detected almost exclusively in neuronal tissues. SK2 mRNA distribution was restricted but more widespread than SK1, and was detected in adrenal gland, brain, prostate, bladder, liver and heart. SK3 mRNA was detected in almost every tissue examined. It was highly expressed in brain and in smooth muscle-rich tissues including the clitoris and the corpus cavernosum, and expression in the corpus cavernosum was upregulated up to 5-fold in patients undergoing sex-change operations. IK1 mRNA was present in surface-rich, secretory and inflammatory cell-rich tissues, highest in the trachea, prostate, placenta and salivary glands. In detailed immunohistochemical studies of the colon and the corpus cavernosum, SK1-like immunoreactivity was observed in the enteric neurons. SK3-like immunoreactivity was observed strongly in smooth muscle and vascular endothelium. IK1-like immunoreactivity was mainly observed in inflammatory cells and enteric neurons of the colon, but absent in corpus cavernosum. These distinctive patterns of distribution suggest that these channels are likely to have different biological functions and could be specifically targeted for a number of human diseases, such as irritable bowel syndrome, hypertension and erectile dysfunction.

Spatial X-ray fluorescence micro-imaging of minerals in grain tissues of wheat and related genotypes.

PubMed

Singh, Sudhir P; Vogel-Mikuš, Katarina; Vavpetič, Primož; Jeromel, Luka; Pelicon, Primož; Kumar, Jitendra; Tuli, Rakesh

2014-08-01

Wheat and its related genotypes show distinct distribution patterns for mineral nutrients in maternal and filial tissues in grains. X-ray-based imaging techniques are very informative to identify genotypes with contrasting tissue-specific localization of different elements. This can help in the selection of suitable genotypes for nutritional improvement of food grain crops. Understanding mineral localization in cereal grains is important for their nutritional improvement. Spatial distribution of mineral nutrients (Mg, P, S, K, Ca, Fe, Zn, Mn and Cu) was investigated between and within the maternal and filial tissues in grains of two wheat cultivars (Triticum aestivum Cv. WH291 and WL711), a landrace (T. aestivum L. IITR26) and a related wild species Aegilops kotschyi, using micro-proton-induced X-ray emission (µ-PIXE) and micro-X-ray fluorescence (µ-XRF). Aleurone and scutellum were major storage tissues for macro (P, K, Ca and Mg) as well as micro (Fe, Zn, Cu and Mn) nutrients. Distinct elemental distribution patterns were observed in each of the four genotypes. A. kotschyi, the wild relative of wheat and the landrace, T. aestivum L. IITR26, accumulated more Zn and Fe in scutellum and aleurone than the cultivated wheat varieties, WH291 and WL711. The landrace IITR26, accumulated far more S in grains, Mn in scutellum, aleurone and embryo region, Ca and Cu in aleurone and scutellum, and Mg, K and P in scutellum than the other genotypes. Unlike wheat, lower Mn and higher Fe, Cu and Zn concentrations were noticed in the pigment strand of A. kotschyi. Multivariate statistical analysis, performed on mineral distribution in major grain tissues (aleurone, scutellum, endosperm and embryo region) resolved the four genotypes into distinct clusters.

Tomographic imaging of bone composition using coherently scattered x rays

NASA Astrophysics Data System (ADS)

Batchelar, Deidre L.; Dabrowski, W.; Cunningham, Ian A.

2000-04-01

Bone tissue consists primarily of calcium hydroxyapatite crystals (bone mineral) and collagen fibrils. Bone mineral density (BMD) is commonly used as an indicator of bone health. Techniques available at present for assessing bone health provide a measure of BMD, but do not provide information about the degree of mineralization of the bone tissue. This may be adequate for assessing diseases in which the collagen-mineral ratio remains constant, as assumed in osteoporosis, but is insufficient when the mineralization state is known to change, as in osteomalacia. No tool exists for the in situ examination of collagen and hydroxyapatite density distributions independently. Coherent-scatter computed tomography (CSCT) is a technique we are developing that produces images of the low- angle scatter properties of tissue. These depend on the molecular structure of the scatterer making it possible to produce material-specific maps of each component in a conglomerate. After corrections to compensate for exposure fluctuations, self-attenuation of scatter and the temporal response of the image intensifier, material-specific images of mineral, collagen, fat and water distributions are obtained. The gray-level in these images provides the volumetric density of each component independently.

Noncontact 3-D Speckle Contrast Diffuse Correlation Tomography of Tissue Blood Flow Distribution.

PubMed

Huang, Chong; Irwin, Daniel; Zhao, Mingjun; Shang, Yu; Agochukwu, Nneamaka; Wong, Lesley; Yu, Guoqiang

2017-10-01

Recent advancements in near-infrared diffuse correlation techniques and instrumentation have opened the path for versatile deep tissue microvasculature blood flow imaging systems. Despite this progress there remains a need for a completely noncontact, noninvasive device with high translatability from small/testing (animal) to large/target (human) subjects with trivial application on both. Accordingly, we discuss our newly developed setup which meets this demand, termed noncontact speckle contrast diffuse correlation tomography (nc_scDCT). The nc_scDCT provides fast, continuous, portable, noninvasive, and inexpensive acquisition of 3-D tomographic deep (up to 10 mm) tissue blood flow distributions with straightforward design and customization. The features presented include a finite-element-method implementation for incorporating complex tissue boundaries, fully noncontact hardware for avoiding tissue compression and interactions, rapid data collection with a diffuse speckle contrast method, reflectance-based design promoting experimental translation, extensibility to related techniques, and robust adjustable source and detector patterns and density for high resolution measurement with flexible regions of interest enabling unique application-specific setups. Validation is shown in the detection and characterization of both high and low contrasts in flow relative to the background using tissue phantoms with a pump-connected tube (high) and phantom spheres (low). Furthermore, in vivo validation of extracting spatiotemporal 3-D blood flow distributions and hyperemic response during forearm cuff occlusion is demonstrated. Finally, the success of instrument feasibility in clinical use is examined through the intraoperative imaging of mastectomy skin flap.

Fast deep-tissue multispectral optoacoustic tomography (MSOT) for preclinical imaging of cancer and cardiovascular disease

NASA Astrophysics Data System (ADS)

Taruttis, Adrian; Razansky, Daniel; Ntziachristos, Vasilis

2012-02-01

Optoacoustic imaging has enabled the visualization of optical contrast at high resolutions in deep tissue. Our Multispectral optoacoustic tomography (MSOT) imaging results reveal internal tissue heterogeneity, where the underlying distribution of specific endogenous and exogenous sources of absorption can be resolved in detail. Technical advances in cardiac imaging allow motion-resolved multispectral measurements of the heart, opening the way for studies of cardiovascular disease. We further demonstrate the fast characterization of the pharmacokinetic profiles of lightabsorbing agents. Overall, our MSOT findings indicate new possibilities in high resolution imaging of functional and molecular parameters.

Long interspersed nuclear elements (LINEs) show tissue-specific, mosaic genome and methylation-unrestricted, widespread expression of noncoding RNAs in somatic tissues of the rat

PubMed Central

Singh, Deepak K.; Rath, Pramod C.

2012-01-01

We report strong somatic and germ line expression of LINE RNAs in eight different tissues of rat by using a novel ~2.8 kb genomic PstI-LINE DNA (P1-LINE) isolated from the rat brain. P1-LINE is present in a 93 kb LINE-SINE-cluster in sub-telomeric region of chromosome 12 (12p12) and as multiple truncated copies interspersed in all rat chromosomes. P1-LINEs occur as inverted repeats at multiple genomic loci in tissue-specific and mosaic patterns. P1-LINE RNAs are strongly expressed in brain, liver, lungs, heart, kidney, testes, spleen and thymus into large to small heterogeneous RNAs (~5.0 to 0.2 kb) in tissue-specific and dynamic patterns in individual rats. P1-LINE DNA is strongly methylated at CpG-dinucleotides in most genomic copies in all the tissues and weakly hypomethylated in few copies in some tissues. Small (700–75 nt) P1-LINE RNAs expressed in all tissues may be possible precursors for small regulatory RNAs (PIWI-interacting/piRNAs) bioinformatically derived from P1-LINE. The strong and dynamic expression of LINE RNAs from multiple chromosomal loci and the putative piRNAs in somatic tissues of rat under normal physiological conditions may define functional chromosomal domains marked by LINE RNAs as long noncoding RNAs (lncRNAs) unrestricted by DNA methylation. The tissue-specific, dynamic RNA expression and mosaic genomic distribution of LINEs representing a steady-state genomic flux of retrotransposon RNAs suggest for biological role of LINE RNAs as long ncRNAs and small piRNAs in mammalian tissues independent of their cellular fate for translation, reverse-transcription and retrotransposition. This may provide evolutionary advantages to LINEs and mammalian genomes. PMID:23064113

Proteomics in Diagnostic Pathology

PubMed Central

Chaurand, Pierre; Sanders, Melinda E.; Jensen, Roy A.; Caprioli, Richard M.

2004-01-01

Direct tissue profiling and imaging mass spectrometry (MS) provide a molecular assessment of numerous expressed proteins within a tissue sample. MALDI MS (matrix-assisted laser desorption ionization) analysis of thin tissue sections results in the visualization of 500 to 1000 individual protein signals in the molecular weight range from 2000 to over 200,000. These signals directly correlate with protein distribution within a specific region of the tissue sample. The systematic investigation of the section allows the construction of ion density maps, or specific molecular images, for virtually every signal detected in the analysis. Ultimately, hundreds of images, each at a specific molecular weight, may be obtained. To date, profiling and imaging MS has been applied to multiple diseased tissues, including human non-small cell lung tumors, gliomas, and breast tumors. Interrogation of the resulting complex MS data sets using modern biocomputational tools has resulted in identification of both disease-state and patient-prognosis specific protein patterns. These studies suggest that such proteomic information will become more and more important in assessing disease progression, prognosis, and drug efficacy. Molecular histology has been known for some time and its value clear in the field of pathology. Imaging mass spectrometry brings a new dimension of molecular data, one focusing on the disease phenotype. The present article reviews the state of the art of the technology and its complementarity with traditional histopathological analyses. PMID:15466373

Current Status and Future Perspectives of Mass Spectrometry Imaging

PubMed Central

Nimesh, Surendra; Mohottalage, Susantha; Vincent, Renaud; Kumarathasan, Prem

2013-01-01

Mass spectrometry imaging is employed for mapping proteins, lipids and metabolites in biological tissues in a morphological context. Although initially developed as a tool for biomarker discovery by imaging the distribution of protein/peptide in tissue sections, the high sensitivity and molecular specificity of this technique have enabled its application to biomolecules, other than proteins, even in cells, latent finger prints and whole organisms. Relatively simple, with no requirement for labelling, homogenization, extraction or reconstitution, the technique has found a variety of applications in molecular biology, pathology, pharmacology and toxicology. By discriminating the spatial distribution of biomolecules in serial sections of tissues, biomarkers of lesions and the biological responses to stressors or diseases can be better understood in the context of structure and function. In this review, we have discussed the advances in the different aspects of mass spectrometry imaging processes, application towards different disciplines and relevance to the field of toxicology. PMID:23759983

Tissue distribution comparison between healthy and fatty liver rats after oral administration of hawthorn leaf extract.

PubMed

Yin, Jingjing; Qu, Jianguo; Zhang, Wenjie; Lu, Dongrui; Gao, Yucong; Ying, Xixiang; Kang, Tingguo

2014-05-01

Hawthorn leaves, a well-known traditional Chinese medicine, have been widely used for treating cardiovascular and fatty liver diseases. The present study aimed to investigate the therapeutic basis treating fatty liver disease by comparing the tissue distribution of six compounds of hawthorn leaf extract (HLE) in fatty liver rats and healthy rats after oral administration at first day, half month and one month, separately. Therefore, a sensitive and specific HPLC method with internal standard was developed and validated to determine chlorogenic acid, vitexin-4''-O-glucoside, vitexin-2''-O-rhamnoside, vitexin, rutin and hyperoside in the tissues including heart, liver, spleen, kidney, stomach and intestine. The results indicated that the six compounds in HLE presented some bioactivity in treating rat fatty liver as the concentrations of the six compounds varied significantly in inter- and intragroup comparisons (healthy and/or fatty liver group). Copyright © 2013 John Wiley & Sons, Ltd.

Dark respiration rate increases with plant size in saplings of three temperate tree species despite decreasing tissue nitrogen and nonstructural carbohydrates.

PubMed

Machado, José-Luis; Reich, Peter B

2006-07-01

In shaded environments, minimizing dark respiration during growth could be an important aspect of maintaining a positive whole-plant net carbon balance. Changes with plant size in both biomass distribution to different tissue types and mass-specific respiration rates (R(d)) of those tissues would have an impact on whole-plant respiration. In this paper, we evaluated size-related variation in R(d), biomass distribution, and nitrogen (N) and total nonstructural carbohydrate (TNC) concentrations of leaves, stems and roots of three cold-temperate tree species (Abies balsamea (L.) Mill, Acer rubrum L. and Pinus strobus L.) in a forest understory. We sampled individuals varying in age (6 to 24 years old) and in size (from 2 to 500 g dry mass), and growing across a range of irradiances (from 1 to 13% of full sun) in northern Minnesota, USA. Within each species, we found small changes in R(d), N and TNC when comparing plants growing across this range of light availability. Consistent with our hypotheses, as plants grew larger, whole-plant N and TNC concentrations in all species declined as a result of a combination of changes in tissue N and shifts in biomass distribution patterns. However, contrary to our hypotheses, whole-plant and tissue R(d) increased with plant size in the three species.

Survey of the Heritability and Sparse Architecture of Gene Expression Traits across Human Tissues.

PubMed

Wheeler, Heather E; Shah, Kaanan P; Brenner, Jonathon; Garcia, Tzintzuni; Aquino-Michaels, Keston; Cox, Nancy J; Nicolae, Dan L; Im, Hae Kyung

2016-11-01

Understanding the genetic architecture of gene expression traits is key to elucidating the underlying mechanisms of complex traits. Here, for the first time, we perform a systematic survey of the heritability and the distribution of effect sizes across all representative tissues in the human body. We find that local h2 can be relatively well characterized with 59% of expressed genes showing significant h2 (FDR < 0.1) in the DGN whole blood cohort. However, current sample sizes (n ≤ 922) do not allow us to compute distal h2. Bayesian Sparse Linear Mixed Model (BSLMM) analysis provides strong evidence that the genetic contribution to local expression traits is dominated by a handful of genetic variants rather than by the collective contribution of a large number of variants each of modest size. In other words, the local architecture of gene expression traits is sparse rather than polygenic across all 40 tissues (from DGN and GTEx) examined. This result is confirmed by the sparsity of optimal performing gene expression predictors via elastic net modeling. To further explore the tissue context specificity, we decompose the expression traits into cross-tissue and tissue-specific components using a novel Orthogonal Tissue Decomposition (OTD) approach. Through a series of simulations we show that the cross-tissue and tissue-specific components are identifiable via OTD. Heritability and sparsity estimates of these derived expression phenotypes show similar characteristics to the original traits. Consistent properties relative to prior GTEx multi-tissue analysis results suggest that these traits reflect the expected biology. Finally, we apply this knowledge to develop prediction models of gene expression traits for all tissues. The prediction models, heritability, and prediction performance R2 for original and decomposed expression phenotypes are made publicly available (https://github.com/hakyimlab/PrediXcan).

Spatiotemporal distribution modeling of PET tracer uptake in solid tumors.

PubMed

Soltani, Madjid; Sefidgar, Mostafa; Bazmara, Hossein; Casey, Michael E; Subramaniam, Rathan M; Wahl, Richard L; Rahmim, Arman

2017-02-01

Distribution of PET tracer uptake is elaborately modeled via a general equation used for solute transport modeling. This model can be used to incorporate various transport parameters of a solid tumor such as hydraulic conductivity of the microvessel wall, transvascular permeability as well as interstitial space parameters. This is especially significant because tracer delivery and drug delivery to solid tumors are determined by similar underlying tumor transport phenomena, and quantifying the former can enable enhanced prediction of the latter. We focused on the commonly utilized FDG PET tracer. First, based on a mathematical model of angiogenesis, the capillary network of a solid tumor and normal tissues around it were generated. The coupling mathematical method, which simultaneously solves for blood flow in the capillary network as well as fluid flow in the interstitium, is used to calculate pressure and velocity distributions. Subsequently, a comprehensive spatiotemporal distribution model (SDM) is applied to accurately model distribution of PET tracer uptake, specifically FDG in this work, within solid tumors. The different transport mechanisms, namely convention and diffusion from vessel to tissue and in tissue, are elaborately calculated across the domain of interest and effect of each parameter on tracer distribution is investigated. The results show the convection terms to have negligible effect on tracer transport and the SDM can be solved after eliminating these terms. The proposed framework of spatiotemporal modeling for PET tracers can be utilized to comprehensively assess the impact of various parameters on the spatiotemporal distribution of PET tracers.

Tissue- and cell-type–specific manifestations of heteroplasmic mtDNA 3243A>G mutation in human induced pluripotent stem cell-derived disease model

PubMed Central

Hämäläinen, Riikka H.; Manninen, Tuula; Koivumäki, Hanna; Kislin, Mikhail; Otonkoski, Timo; Suomalainen, Anu

2013-01-01

Mitochondrial DNA (mtDNA) mutations manifest with vast clinical heterogeneity. The molecular basis of this variability is mostly unknown because the lack of model systems has hampered mechanistic studies. We generated induced pluripotent stem cells from patients carrying the most common human disease mutation in mtDNA, m.3243A>G, underlying mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome. During reprogramming, heteroplasmic mtDNA showed bimodal segregation toward homoplasmy, with concomitant changes in mtDNA organization, mimicking mtDNA bottleneck during epiblast specification. Induced pluripotent stem cell–derived neurons and various tissues derived from teratomas manifested cell-type specific respiratory chain (RC) deficiency patterns. Similar to MELAS patient tissues, complex I defect predominated. Upon neuronal differentiation, complex I specifically was sequestered in perinuclear PTEN-induced putative kinase 1 (PINK1) and Parkin-positive autophagosomes, suggesting active degradation through mitophagy. Other RC enzymes showed normal mitochondrial network distribution. Our data show that cellular context actively modifies RC deficiency manifestation in MELAS and that autophagy is a significant component of neuronal MELAS pathogenesis. PMID:24003133

Mammalian monoamine-oxidizing enzymes, with special reference to benzylamine oxidase in human tissues.

PubMed

Lewinsohn, R

1984-01-01

A review is presented of the monoamine-oxidizing enzymes with special reference to the activity of benzylamine oxidase (BzAO) in human tissues. Methods of study of amine oxidases, properties (chiefly of BzAO) and some problems concerning substrate and inhibitor specificity and multiple forms of monoamine oxidase (MAO) are surveyed. The substrate specificity of human plasma BzAO is compared with that of amine-oxidizing enzymes in plasma or serum of other species. Correlations of plasma BzAO and platelet MAO activity with clinical findings are discussed. The distribution of amine oxidase activities in solid human tissues is reviewed, in particular BzAO in blood vessels and richly-vascularized tissues, as well as kinetic constants and altered patterns of activity of BzAO in human atherosclerosis. Activities of the amine oxidases in non-vascular smooth muscle, in cultured cells, and in various tissues related to human gestation, are discussed. The present knowledge of BzAO is discussed in terms of its possible clinical relevance to several human disease states, and the importance of the enzyme in the human body.

Tissue specific distribution of pyrimidine deoxynucleoside salvage enzymes shed light on the mechanism of mitochondrial DNA depletion.

PubMed

Wang, L; Eriksson, S

2010-06-01

Deficiency in thymidine kinase 2 (TK2) activity due to genetic alterations caused tissue specific mitochondrial DNA (mtDNA) depletion syndrome with symptoms resembling these of AIDS patients treated with nucleoside analogues. Mechanisms behind this mitochondrial effects is still not well understood. With rat as a model we isolated mitochondrial and cytosolic fractions from major organs and studied enzymes involved in thymidine (dT) and deoxycytidine (dC) phosphorylation by using ionic exchange column chromatography. A cytosolic form of TK2 was identified in all tested tissues in addition to mitochondrial TK2. TK1 was detected in liver and spleen cytosolic extracts while dCK was found in liver, spleen and lung cytosolic extracts. Thus, the nature of dT and dC salvage enzymes in each tissue type was determined. In most tissues TK2 is the only salvage enzyme present except liver and spleen. These results may help to explain the mechanisms of mitochondrial toxicity of antiviral nucleoside analogues and mtDNA depletion caused by TK2 deficiency.

Immunochemical detection of food-derived polyphenols in the aorta: macrophages as a major target underlying the anti-atherosclerotic activity of polyphenols.

PubMed

Kawai, Yoshichika

2011-01-01

It has been suggested that polyphenol-rich diets decrease the risk of cardiovascular diseases. Although studies of the bioavailability of polyphenols, particularly their absorption and metabolism, have been reported recently, the tissue and cellular distributions underlying their biological mechanisms remain unknown. It is difficult to evaluate the specific localization of tissue and/or cellular polyphenols, because the method is limited to chromatography. To overcome these difficulties, we have developed anti-polyphenol antibodies to characterize immunohistochemically the localization of polyphenols and their metabolites in vivo. Two novel monoclonal antibodies were raised against quercetin and tea catechins, which represent flavonoid-type polyphenols distributed in foods and beverages, and are expected to exhibit anti-oxidative and anti-inflammatory activities in vivo. Using these antibodies, we identified activated macrophages as a specific target of these flavonoids during the development of atherosclerotic lesions. This review describes recent findings on the molecular actions of flavonoids that underly their anti-atherosclerotic activity in vivo.

Tissue distribution and cell tropism of Brucella canis in naturally infected canine foetuses and neonates.

PubMed

de Souza, Tayse Domingues; de Carvalho, Tatiane Furtado; Mol, Juliana Pinto da Silva; Lopes, João Vítor Menezes; Silva, Monique Ferreira; da Paixão, Tatiane Alves; Santos, Renato Lima

2018-05-08

Brucella canis infection is an underdiagnosed zoonotic disease. Knowledge about perinatal brucellosis in dogs is extremely limited, although foetuses and neonates are under risk of infection due to vertical transmission. In this study, immunohistochemistry was used to determine tissue distribution and cell tropism of B. canis in canine foetuses and neonates. Diagnosis of B. canis in tissues of naturally infected pups was based on PCR and sequencing of amplicons, bacterial isolation, and immunohistochemistry, whose specificity was confirmed by laser capture microdissection. PCR positivity among 200 puppies was 21%, and nine isolates of B. canis were obtained. Tissues from 13 PCR-positive puppies (4 stillborn and 9 neonates) presented widespread immunolabeling. Stomach, intestines, kidney, nervous system, and umbilicus were positive in all animals tested. Other frequently infected organs included the liver (92%), lungs (85%), lymph nodes (69%), and spleen (62%). Immunolabeled coccobacilli occurred mostly in macrophages, but they were also observed in erythrocytes, epithelial cells of gastrointestinal mucosa, renal tubules, epidermis, adipocytes, choroid plexus, ependyma, neuroblasts, blood vessels endothelium, muscle cells, and in the intestinal lumen. These results largely expand our knowledge about perinatal brucellosis in the dog, clearly demonstrating a pantropic distribution of B. canis in naturally infected foetuses and neonates.

Proteome-wide characterization of sugarbeet seed vigor and its tissue specific expression

PubMed Central

Catusse, Julie; Strub, Jean-Marc; Job, Claudette; Van Dorsselaer, Alain; Job, Dominique

2008-01-01

Proteomic analysis of mature sugarbeet seeds led to the identification of 759 proteins and their specific tissue expression in root, cotyledons, and perisperm. In particular, the proteome of the perispermic storage tissue found in many seeds of the Caryophyllales is described here. The data allowed us to reconstruct in detail the metabolism of the seeds toward recapitulating facets of seed development and provided insights into complex behaviors such as germination. The seed appears to be well prepared to mobilize the major classes of reserves (the proteins, triglycerides, phytate, and starch) during germination, indicating that the preparation of the seed for germination is mainly achieved during its maturation on the mother plant. Furthermore, the data revealed several pathways that can contribute to seed vigor, an important agronomic trait defined as the potential to produce vigorous seedlings, such as glycine betaine accumulation in seeds. This study also identified several proteins that, to our knowledge, have not previously been described in seeds. For example, the data revealed that the sugarbeet seed can initiate translation either through the traditional cap-dependent mechanism or by a cap-independent process. The study of the tissue specificity of the seed proteome demonstrated a compartmentalization of metabolic activity between the roots, cotyledons, and perisperm, indicating a division of metabolic tasks between the various tissues. Furthermore, the perisperm, although it is known as a dead tissue, appears to be very active biochemically, playing multiple roles in distributing sugars and various metabolites to other tissues of the embryo. PMID:18635686

Overview about the localization of nanoparticles in tissue and cellular context by different imaging techniques

PubMed Central

Ostrowski, Anja; Nordmeyer, Daniel; Boreham, Alexander; Holzhausen, Cornelia; Mundhenk, Lars; Graf, Christina; Meinke, Martina C; Vogt, Annika; Hadam, Sabrina; Lademann, Jürgen; Rühl, Eckart; Alexiev, Ulrike

2015-01-01

Summary The increasing interest and recent developments in nanotechnology pose previously unparalleled challenges in understanding the effects of nanoparticles on living tissues. Despite significant progress in in vitro cell and tissue culture technologies, observations on particle distribution and tissue responses in whole organisms are still indispensable. In addition to a thorough understanding of complex tissue responses which is the domain of expert pathologists, the localization of particles at their sites of interaction with living structures is essential to complete the picture. In this review we will describe and compare different imaging techniques for localizing inorganic as well as organic nanoparticles in tissues, cells and subcellular compartments. The visualization techniques include well-established methods, such as standard light, fluorescence, transmission electron and scanning electron microscopy as well as more recent developments, such as light and electron microscopic autoradiography, fluorescence lifetime imaging, spectral imaging and linear unmixing, superresolution structured illumination, Raman microspectroscopy and X-ray microscopy. Importantly, all methodologies described allow for the simultaneous visualization of nanoparticles and evaluation of cell and tissue changes that are of prime interest for toxicopathologic studies. However, the different approaches vary in terms of applicability for specific particles, sensitivity, optical resolution, technical requirements and thus availability, and effects of labeling on particle properties. Specific bottle necks of each technology are discussed in detail. Interpretation of particle localization data from any of these techniques should therefore respect their specific merits and limitations as no single approach combines all desired properties. PMID:25671170

MRI-guided fluorescence tomography of the breast: a phantom study

NASA Astrophysics Data System (ADS)

Davis, Scott C.; Pogue, Brian W.; Dehghani, Hamid; Paulsen, Keith D.

2009-02-01

Tissue phantoms simulating the human breast were used to demonstrate the imaging capabilities of an MRI-coupled fluorescence molecular tomography (FMT) imaging system. Specifically, phantoms with low tumor-to-normal drug contrast and complex internal structure were imaged with the MR-coupled FMT system. Images of indocyanine green (ICG) fluorescence yield were recovered using a diffusion model-based approach capable of estimating the distribution of fluorescence activity in a tissue volume from tissue-boundary measurements of transmitted light. Tissue structural information, which can be determined from standard T1 and T2 MR images, was used to guide the recovery of fluorescence activity. The study revealed that this spatial guidance is critical for recovering images of fluorescence yield in tissue with low tumor-to-normal drug contrast.

Incorporation of lysosomal sequestration in the mechanistic model for prediction of tissue distribution of basic drugs.

PubMed

Assmus, Frauke; Houston, J Brian; Galetin, Aleksandra

2017-11-15

The prediction of tissue-to-plasma water partition coefficients (Kpu) from in vitro and in silico data using the tissue-composition based model (Rodgers & Rowland, J Pharm Sci. 2005, 94(6):1237-48.) is well established. However, distribution of basic drugs, in particular into lysosome-rich lung tissue, tends to be under-predicted by this approach. The aim of this study was to develop an extended mechanistic model for the prediction of Kpu which accounts for lysosomal sequestration and the contribution of different cell types in the tissue of interest. The extended model is based on compound-specific physicochemical properties and tissue composition data to describe drug ionization, distribution into tissue water and drug binding to neutral lipids, neutral phospholipids and acidic phospholipids in tissues, including lysosomes. Physiological data on the types of cells contributing to lung, kidney and liver, their lysosomal content and lysosomal pH were collated from the literature. The predictive power of the extended mechanistic model was evaluated using a dataset of 28 basic drugs (pK a ≥7.8, 17 β-blockers, 11 structurally diverse drugs) for which experimentally determined Kpu data in rat tissue have been reported. Accounting for the lysosomal sequestration in the extended mechanistic model improved the accuracy of Kpu predictions in lung compared to the original Rodgers model (56% drugs within 2-fold or 88% within 3-fold of observed values). Reduction in the extent of Kpu under-prediction was also evident in liver and kidney. However, consideration of lysosomal sequestration increased the occurrence of over-predictions, yielding overall comparable model performances for kidney and liver, with 68% and 54% of Kpu values within 2-fold error, respectively. High lysosomal concentration ratios relative to cytosol (>1000-fold) were predicted for the drugs investigated; the extent differed depending on the lysosomal pH and concentration of acidic phospholipids among cell types. Despite this extensive lysosomal sequestration in the individual cells types, the maximal change in the overall predicted tissue Kpu was <3-fold for lysosome-rich tissues investigated here. Accounting for the variability in cellular physiological model input parameters, in particular lysosomal pH and fraction of the cellular volume occupied by the lysosomes, only partially explained discrepancies between observed and predicted Kpu data in the lung. Improved understanding of the system properties, e.g., cell/organelle composition is required to support further development of mechanistic equations for the prediction of drug tissue distribution. Application of this revised mechanistic model is recommended for prediction of Kpu in lysosome-rich tissue to facilitate the advancement of physiologically-based prediction of volume of distribution and drug exposure in the tissues. Copyright © 2017 Elsevier B.V. All rights reserved.

Protein kinase C isoforms in iris sphincter smooth muscle: differential effects of phorbol ester on contraction and cAMP accumulation are species specific.

PubMed

Husain, S; Abdel-Latif, A A

1996-03-01

Objectives were to identify PKC isoforms in iris sphincter isolated from rabbit, cat, dog and bovine irides, to determine their subcellular distribution, and to investigate the effects of the phorbol ester, PDBu, on contraction and cAMP accumulation in this tissue. Using six isoform (alpha, beta, gamma, epsilon, delta, zeta)-specific polyclonal antibodies, PKC alpha, beta, epsilon, delta, and zeta were detected in the four species, whereas PKC gamma was detected only in dog and bovine. PKC alpha and epsilon are the most abundant isoforms in this tissue. PKC alpha is mainly cytosolic in rabbit and bovine and membrane associated in cat and dog. PKC gamma is equally distributed in cytosol and membrane fractions of bovine, but mostly cytosolic in dog. PKC beta, delta and epsilon are mainly membraneous and PKC zeta is mainly cytosolic in all species. PDBu (100 nM) induced a contractile response in rabbit- and cat-, but not in dog and bovine, sphincters, and increased cAMP accumulation in rabbit, cat, dog and bovine by 111, 130, 458 and 294%, respectively. Therefore, the lack of effect of PDBu on contraction in dog and bovine, as compared to rabbit and cat, may be due: (a) to the presence of PKC gamma isoform, and (b) to the stronger stimulatory effects of the phorbol ester on cAMP production in the non-contracting species. In addition to demonstrating the presence of various PKC isoforms in the iris sphincter and the activation of adenylyl cyclase by this protein kinase, we have shown that the distribution of the PKC isoforms in this tissue is species specific. Furthermore, our data suggest that there may be specific physiological functions associated with each of the PKC isoforms and that PKC is involved in the contractile response of some but not all smooth muscles.

Preclinical evaluation of nuclear morphometry and tissue topology for breast carcinoma detection and margin assessment

PubMed Central

Nyirenda, Ndeke; Farkas, Daniel L.

2010-01-01

Prevention and early detection of breast cancer are the major prophylactic measures taken to reduce the breast cancer related mortality and morbidity. Clinical management of breast cancer largely relies on the efficacy of the breast-conserving surgeries and the subsequent radiation therapy. A key problem that limits the success of these surgeries is the lack of accurate, real-time knowledge about the positive tumor margins in the surgically excised tumors in the operating room. This leads to tumor recurrence and, hence, the need for repeated surgeries. Current intraoperative techniques such as frozen section pathology or touch imprint cytology severely suffer from poor sampling and non-optimal detection sensitivity. Even though histopathology analysis can provide information on positive tumor margins post-operatively (~2–3 days), this information is of no immediate utility in the operating rooms. In this article, we propose a novel image analysis method for tumor margin assessment based on nuclear morphometry and tissue topology and demonstrate its high sensitivity/specificity in preclinical animal model of breast carcinoma. The method relies on imaging nuclear-specific fluorescence in the excised surgical specimen and on extracting nuclear morphometric parameters (size, number, and area fraction) from the spatial distribution of the observed fluorescence in the tissue. We also report the utility of tissue topology in tumor margin assessment by measuring the fractal dimension in the same set of images. By a systematic analysis of multiple breast tissues specimens, we show here that the proposed method is not only accurate (~97% sensitivity and 96% specificity) in thin sections, but also in three-dimensional (3D) thick tissues that mimic the realistic lumpectomy specimens. Our data clearly precludes the utility of nuclear size as a reliable diagnostic criterion for tumor margin assessment. On the other hand, nuclear area fraction addresses this issue very effectively since it is a combination of both nuclear size and count in any given region of the analyzed image, and thus yields high sensitivity and specificity (~97%) in tumor detection. This is further substantiated by an independent parameter, fractal dimension, based on the tissue topology. Although the basic definition of cancer as an uncontrolled cell growth entails a high nuclear density in tumor regions, a simple but systematic exploration of nuclear distribution in thick tissues by nuclear morphometry and tissue topology as performed in this study has never been carried out, to the best of our knowledge. We discuss the practical aspects of implementing this imaging approach in automated tissue sampling scenario where the accuracy of tumor margin assessment can be significantly increased by scanning the entire surgical specimen rather than sampling only a few sections as in current histopathology analysis. PMID:20446030

A deep learning approach to estimate stress distribution: a fast and accurate surrogate of finite-element analysis.

PubMed

Liang, Liang; Liu, Minliang; Martin, Caitlin; Sun, Wei

2018-01-01

Structural finite-element analysis (FEA) has been widely used to study the biomechanics of human tissues and organs, as well as tissue-medical device interactions, and treatment strategies. However, patient-specific FEA models usually require complex procedures to set up and long computing times to obtain final simulation results, preventing prompt feedback to clinicians in time-sensitive clinical applications. In this study, by using machine learning techniques, we developed a deep learning (DL) model to directly estimate the stress distributions of the aorta. The DL model was designed and trained to take the input of FEA and directly output the aortic wall stress distributions, bypassing the FEA calculation process. The trained DL model is capable of predicting the stress distributions with average errors of 0.492% and 0.891% in the Von Mises stress distribution and peak Von Mises stress, respectively. This study marks, to our knowledge, the first study that demonstrates the feasibility and great potential of using the DL technique as a fast and accurate surrogate of FEA for stress analysis. © 2018 The Author(s).

Temperature-controlled radiofrequency ablation of different tissues using two-compartment models.

PubMed

Singh, Sundeep; Repaka, Ramjee

2016-08-30

This study aims to analyse the efficacy of temperature-controlled radiofrequency ablation (RFA) in different tissues. A three-dimensional, 12 cm cubical model representing the healthy tissue has been studied in which spherical tumour of 2.5 cm has been embedded. Different body sites considered in the study are liver, kidney, lung and breast. The thermo-electric analysis has been performed to estimate the temperature distribution and ablation volume. A programmable temperature-controlled RFA has been employed by incorporating the closed-loop feedback PID controller. The model fidelity and integrity have been evaluated by comparing the numerical results with the experimental in vitro results obtained during RFA of polyacrylamide tissue-mimicking phantom gel. The results revealed that significant variations persist among the input voltage requirements and the temperature distributions within different tissues of interest. The highest ablation volume has been produced in hypovascular lungs whereas least ablation volume has been produced in kidney being a highly perfused tissue. The variation in optimal treatment time for complete necrosis of tumour along with quantification of damage to the surrounding healthy tissue has also been reported. The results show that the surrounding tissue environment significantly affects the ablation volume produced during RFA. The optimal treatment time for complete tumour ablation can play a critical role in minimising the damage to the surrounding healthy tissue and ensuring safe and risk free application of RFA. The obtained results emphasise the need for developing organ-specific clinical protocols and systems during RFA of tumour.

Diet-induced obesity, exogenous leptin-, and MADB106 tumor cell challenge affect tissue leukocyte distribution and serum levels of cytokines in F344 rats.

PubMed

Behrendt, Patrick; Buchenauer, Tobias; Horn, Rüdiger; Brabant, Georg; Jacobs, Roland; Bode, Felix; Stephan, Michael; Nave, Heike

2010-08-01

The adipocyte-derived catabolic protein leptin alters cell-mediated immunity and cytokine crosstalk. This may provide new insights into the altered immune response, seen in obese individuals. Therefore, we determined the tissue distribution of immune cells in diet-induced obese (dio) and normal weight F344 rats challenged with MADB106 tumor cells or leptin. Immune cell distribution in blood (by FACS analysis) and tissues (NK cells in spleen and liver, immunohistologically) as well as pro-inflammatory cytokines (IL-6, TNF-α; by flow cytometry) were investigated in 28 normal weight and 28 dio rats (n = 4-6/group). Pro-inflammatory cytokines were increased 3-fold for IL-6 and 7-fold for TNF-α in obese animals. Higher numbers of blood monocytes and NK cells were found in obese as compared to normal weight animals. In dio rats challenged with leptin and MADB106 tumor cells, monocyte numbers were decreased as compared to the obese control animals. Immunohistochemistry revealed an altered NK cell distribution in a compartment-, treatment-, and bodyweight-specific manner. In conclusion, our data reveal a distinct distribution pattern of monocytes and NK cells in dio rats as compared to normal weight littermates and an additional modulatory effect of a leptin- and MADB106 tumor cell challenge.

Differential distribution of adenosine receptors in rat cochlea.

PubMed

Vlajkovic, Srdjan M; Abi, Shukri; Wang, Carol J H; Housley, Gary D; Thorne, Peter R

2007-06-01

Adenosine is a constitutive cell metabolite that can be released from cells via specific bi-directional transporters and is an end-point for nucleotide hydrolysis. In the extracellular space, adenosine becomes a signalling molecule for P1 (adenosine) receptors that modulate physiological responses in a wide range of mammalian tissues. Whereas adenosine signalling has been implicated in the regulation of cochlear blood flow and in cochlear protection from oxidative damage, the potential roles for adenosine signalling in the modulation of sound transduction and auditory neurotransmission have not been established. We have characterised the expression and distribution of adenosine receptors in the rat cochlea. mRNA transcripts for all four subtypes of adenosine receptors (A(1), A(2A), A(2B) and A(3)) were detected in dissected cochlear tissue by using reverse transcription/polymerase chain reaction analysis. The protein distribution for the A(1), A(2A) and A(3) receptor subtypes was identified by immunoperoxidase histochemistry and confocal immunofluorescence labelling. These receptors were differentially expressed in the organ of Corti, spiral ganglion neurones, lateral wall tissues and cochlear blood vessels. The distribution of adenosine receptors in sensory and neural tissues and in the vasculature coincided with other elements of purinergic signalling (P2X and P2Y receptors, ectonucleotidases), consistent with the integrative regulation of many physiological processes in the cochlea by extracellular nucleotides and nucleosides. Our study provides a framework for further investigation of adenosine signalling in the inner ear, including putative roles in oxidative stress responses.

Atrial natriuretic factor receptor heterogeneity in rat tissues

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

Andresen, J.W.; Kuno, T.; Kamisaki, Y.

1986-03-01

Rat /sup 125/I-atrial natriuretic factor (ANF, 8-33) was used to identify ANF receptors in membrane preparations from rat adrenal gland and lung. When solubilized with Lubrol-PX, the receptors retained a binding profile and properties that correspond to the high affinity and specificity found in crude membranes. Single peaks of binding activity were observed in gel permeation HPLC and density gradient centrifugation analysis of the solubilized preparations. However, when membranes and solubilized preparations were labeled with /sup 125/I-ANF, treated with crosslinking reagent (disuccinimidyl suberate), and analyzed by SDS gel electrophoresis several specifically labeled bands (120,000, 70,000, and 60,000 daltons) were identifiedmore » by autoradiography. The relative distribution of the specifically labeled proteins varied significantly between rat adrenal gland and lung. In adrenal glands the 120K dalton band was the most prominent specifically labeled protein, while the 60K and 70K dalton proteins were labeled to a lesser degree. In lung membranes the lower molecular weight proteins were more prominent. These results suggest the presence of multiple ANF receptor subtypes, the distribution of which varies among tissues. Chromatographic separation and further characterization of these receptors are currently in progress, and preliminary purification studies support this hypothesis.« less

Three-dimensional histology: tools and application to quantitative assessment of cell-type distribution in rabbit heart

PubMed Central

Burton, Rebecca A.B.; Lee, Peter; Casero, Ramón; Garny, Alan; Siedlecka, Urszula; Schneider, Jürgen E.; Kohl, Peter; Grau, Vicente

2014-01-01

Aims Cardiac histo-anatomical organization is a major determinant of function. Changes in tissue structure are a relevant factor in normal and disease development, and form targets of therapeutic interventions. The purpose of this study was to test tools aimed to allow quantitative assessment of cell-type distribution from large histology and magnetic resonance imaging- (MRI) based datasets. Methods and results Rabbit heart fixation during cardioplegic arrest and MRI were followed by serial sectioning of the whole heart and light-microscopic imaging of trichrome-stained tissue. Segmentation techniques developed specifically for this project were applied to segment myocardial tissue in the MRI and histology datasets. In addition, histology slices were segmented into myocytes, connective tissue, and undefined. A bounding surface, containing the whole heart, was established for both MRI and histology. Volumes contained in the bounding surface (called ‘anatomical volume’), as well as that identified as containing any of the above tissue categories (called ‘morphological volume’), were calculated. The anatomical volume was 7.8 cm3 in MRI, and this reduced to 4.9 cm3 after histological processing, representing an ‘anatomical’ shrinkage by 37.2%. The morphological volume decreased by 48% between MRI and histology, highlighting the presence of additional tissue-level shrinkage (e.g. an increase in interstitial cleft space). The ratio of pixels classified as containing myocytes to pixels identified as non-myocytes was roughly 6:1 (61.6 vs. 9.8%; the remaining fraction of 28.6% was ‘undefined’). Conclusion Qualitative and quantitative differentiation between myocytes and connective tissue, using state-of-the-art high-resolution serial histology techniques, allows identification of cell-type distribution in whole-heart datasets. Comparison with MRI illustrates a pronounced reduction in anatomical and morphological volumes during histology processing. PMID:25362175

Characterization and localization of /sup 3/H-arginine8-vasopressin binding to rat kidney and brain tissue

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

Dorsa, D.M.; Majumdar, L.A.; Petracca, F.M.

Anatomic, behavioral and pharmacologic evidence suggests that arginine8-vasopressin (AVP) serves as a CNS neurotransmitter or neuromodulator. AVP binding to membrane and tissue slice preparations from brain and kidney was characterized, and the anatomical distribution of these binding sites was examined. Conditions for the binding assay were optimized using kidney medullary tissue. Binding of /sup 3/H-AVP (S.A. . 30-51 Ci/mmol, NEN) to brain and kidney membranes and tissue slices was saturable, temperature dependent, linearly related to protein concentration (or number of tissue slices), reversible, and specific since the ability of cold AVP to displace /sup 3/H-AVP from binding was greater thanmore » oxytocin and other related peptide fragments. Autoradiographic localization of /sup 3/H-AVP binding was restricted to kidney medullary tissue. In brain tissue, /sup 3/H-AVP binding was found to occur in concentrated foci. Brainstem areas such as the nucleus tractus solitarius (NTS) showed a high density of AVP binding sites. Since local injections of AVP into the NTS have been shown to influence blood pressure, the present study presents the first anatomical evidence for the presence of AVP specific binding sites which might mediate this effect.« less

Localization of PPAR isotypes in the adult mouse and human brain

PubMed Central

Warden, Anna; Truitt, Jay; Merriman, Morgan; Ponomareva, Olga; Jameson, Kelly; Ferguson, Laura B.; Mayfield, R. Dayne; Harris, R. Adron

2016-01-01

Peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors that act as ligand-activated transcription factors. PPAR agonists have well-documented anti-inflammatory and neuroprotective roles in the central nervous system. Recent evidence suggests that PPAR agonists are attractive therapeutic agents for treating neurodegenerative diseases as well as addiction. However, the distribution of PPAR mRNA and protein in brain regions associated with these conditions (i.e. prefrontal cortex, nucleus accumbens, amygdala, ventral tegmental area) is not well defined. Moreover, the cell type specificity of PPARs in mouse and human brain tissue has yet to be investigated. We utilized quantitative PCR and double immunofluorescence microscopy to determine that both PPAR mRNA and protein are expressed ubiquitously throughout the adult mouse brain. We found that PPARs have unique cell type specificities that are consistent between species. PPARα was the only isotype to colocalize with all cell types in both adult mouse and adult human brain tissue. Overall, we observed a strong neuronal signature, which raises the possibility that PPAR agonists may be targeting neurons rather than glia to produce neuroprotection. Our results fill critical gaps in PPAR distribution and define novel cell type specificity profiles in the adult mouse and human brain. PMID:27283430

Localization of PPAR isotypes in the adult mouse and human brain.

PubMed

Warden, Anna; Truitt, Jay; Merriman, Morgan; Ponomareva, Olga; Jameson, Kelly; Ferguson, Laura B; Mayfield, R Dayne; Harris, R Adron

2016-06-10

Peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors that act as ligand-activated transcription factors. PPAR agonists have well-documented anti-inflammatory and neuroprotective roles in the central nervous system. Recent evidence suggests that PPAR agonists are attractive therapeutic agents for treating neurodegenerative diseases as well as addiction. However, the distribution of PPAR mRNA and protein in brain regions associated with these conditions (i.e. prefrontal cortex, nucleus accumbens, amygdala, ventral tegmental area) is not well defined. Moreover, the cell type specificity of PPARs in mouse and human brain tissue has yet to be investigated. We utilized quantitative PCR and double immunofluorescence microscopy to determine that both PPAR mRNA and protein are expressed ubiquitously throughout the adult mouse brain. We found that PPARs have unique cell type specificities that are consistent between species. PPARα was the only isotype to colocalize with all cell types in both adult mouse and adult human brain tissue. Overall, we observed a strong neuronal signature, which raises the possibility that PPAR agonists may be targeting neurons rather than glia to produce neuroprotection. Our results fill critical gaps in PPAR distribution and define novel cell type specificity profiles in the adult mouse and human brain.

Fabrication of scaffolds in tissue engineering: A review

NASA Astrophysics Data System (ADS)

Zhao, Peng; Gu, Haibing; Mi, Haoyang; Rao, Chengchen; Fu, Jianzhong; Turng, Lih-sheng

2018-03-01

Tissue engineering (TE) is an integrated discipline that involves engineering and natural science in the development of biological materials to replace, repair, and improve the function of diseased or missing tissues. Traditional medical and surgical treatments have been reported to have side effects on patients caused by organ necrosis and tissue loss. However, engineered tissues and organs provide a new way to cure specific diseases. Scaffold fabrication is an important step in the TE process. This paper summarizes and reviews the widely used scaffold fabrication methods, including conventional methods, electrospinning, three-dimensional printing, and a combination of molding techniques. Furthermore, the differences among the properties of tissues, such as pore size and distribution, porosity, structure, and mechanical properties, are elucidated and critically reviewed. Some studies that combine two or more methods are also reviewed. Finally, this paper provides some guidance and suggestions for the future of scaffold fabrication.

In situ detection of the activation of Rac1 and RalA small GTPases in mouse adipocytes by immunofluorescent microscopy following in vivo and ex vivo insulin stimulation.

PubMed

Takenaka, Nobuyuki; Nihata, Yuma; Ueda, Sho; Satoh, Takaya

2017-11-01

Rac1 has been implicated in insulin-dependent glucose uptake by mechanisms involving plasma membrane translocation of the glucose transporter GLUT4 in skeletal muscle. Although the uptake of glucose is also stimulated by insulin in adipose tissue, the role for Rac1 in adipocyte insulin signaling remains controversial. As a step to reveal the role for Rac1 in adipocytes, we aimed to establish immunofluorescent microscopy to detect the intracellular distribution of activated Rac1. The epitope-tagged Rac1-binding domain of a Rac1-specific target was utilized as a probe that specifically recognizes the activated form of Rac1. Rac1 activation in response to ex vivo and in vivo insulin stimulations in primary adipocyte culture and mouse white adipose tissue, respectively, was successfully observed by immunofluorescent microscopy. These Rac1 activations were mediated by phosphoinositide 3-kinase. Another small GTPase RalA has also been implicated in insulin-stimulated glucose uptake in skeletal muscle and adipose tissue. Similarly to Rac1, immunofluorescent microscopy using an activated RalA-specific polypeptide probe allowed us to detect intracellular distribution of insulin-activated RalA in adipocytes. These novel approaches to visualize the activation status of small GTPases in adipocytes will largely contribute to the understanding of signal transduction mechanisms particularly for insulin action. Copyright © 2017 Elsevier Inc. All rights reserved.

Two distinct events, section compression and loss of particles ("lost caps"), contribute to z-axis distortion and bias in optical disector counting.

PubMed

Baryshnikova, Larisa M; Von Bohlen Und Halbach, Oliver; Kaplan, Suleyman; Von Bartheld, Christopher S

2006-09-01

Deformation of tissue sections in the z-axis can bias optical disector counting. When samples of particle densities are not representative for the entire tissue section, significant bias of estimated numbers can result. To assess the occurrence, prevalence, extent, sequence of events, and causes of z-axis distortion, the distribution of neuronal nucleoli in thick paraffin and vibratome sections was determined in chicken, rodent, and human brain tissues. When positions of neuronal nucleoli were measured in the z-axis, nucleoli were more frequent at the surfaces (bottom and top) of tissue sections than in the core. This nonlinear z-axis distribution was not lab-, equipment-, or investigator-specific, and was independent of age, fixation quality, coverslipping medium, or paraffin melting temperature, but in paraffin sections, was highly correlated with the tilt of the knife (cutting) angle. Manipulation of subsequent tissue processing steps revealed that two events contribute to z-axis distortion. Initially, a higher density of particles results at surfaces after sectioning, apparently due to section compression. Subsequently, particles can be lost to varying degrees from surfaces during floating or staining and dehydration, resulting in "lost caps." These results may explain different degrees of z-axis distortion between different types of sections and different labs, and reinforce the importance of checking z-axis distributions as a "quality control" prior to selection of guard zones in optical disector counting. Indirect approaches to assess section quality, such as resectioning in a perpendicular plane, yield additional artifacts, and should be replaced by a direct quantitative measurement of z-axis distribution of particles. (c) 2006 Wiley-Liss, Inc.

Plexin D1 determines body fat distribution by regulating the type V collagen microenvironment in visceral adipose tissue.

PubMed

Minchin, James E N; Dahlman, Ingrid; Harvey, Christopher J; Mejhert, Niklas; Singh, Manvendra K; Epstein, Jonathan A; Arner, Peter; Torres-Vázquez, Jesús; Rawls, John F

2015-04-07

Genome-wide association studies have implicated PLEXIN D1 (PLXND1) in body fat distribution and type 2 diabetes. However, a role for PLXND1 in regional adiposity and insulin resistance is unknown. Here we use in vivo imaging and genetic analysis in zebrafish to show that Plxnd1 regulates body fat distribution and insulin sensitivity. Plxnd1 deficiency in zebrafish induced hyperplastic morphology in visceral adipose tissue (VAT) and reduced lipid storage. In contrast, subcutaneous adipose tissue (SAT) growth and morphology were unaffected, resulting in altered body fat distribution and a reduced VAT:SAT ratio in zebrafish. A VAT-specific role for Plxnd1 appeared conserved in humans, as PLXND1 mRNA was positively associated with hypertrophic morphology in VAT, but not SAT. In zebrafish plxnd1 mutants, the effect on VAT morphology and body fat distribution was dependent on induction of the extracellular matrix protein collagen type V alpha 1 (col5a1). Furthermore, after high-fat feeding, zebrafish plxnd1 mutant VAT was resistant to expansion, and excess lipid was disproportionately deposited in SAT, leading to an even greater exacerbation of altered body fat distribution. Plxnd1-deficient zebrafish were protected from high-fat-diet-induced insulin resistance, and human VAT PLXND1 mRNA was positively associated with type 2 diabetes, suggesting a conserved role for PLXND1 in insulin sensitivity. Together, our findings identify Plxnd1 as a novel regulator of VAT growth, body fat distribution, and insulin sensitivity in both zebrafish and humans.

Detector-specific correction factors in radiosurgery beams and their impact on dose distribution calculations.

PubMed

García-Garduño, Olivia A; Rodríguez-Ávila, Manuel A; Lárraga-Gutiérrez, José M

2018-01-01

Silicon-diode-based detectors are commonly used for the dosimetry of small radiotherapy beams due to their relatively small volumes and high sensitivity to ionizing radiation. Nevertheless, silicon-diode-based detectors tend to over-respond in small fields because of their high density relative to water. For that reason, detector-specific beam correction factors ([Formula: see text]) have been recommended not only to correct the total scatter factors but also to correct the tissue maximum and off-axis ratios. However, the application of [Formula: see text] to in-depth and off-axis locations has not been studied. The goal of this work is to address the impact of the correction factors on the calculated dose distribution in static non-conventional photon beams (specifically, in stereotactic radiosurgery with circular collimators). To achieve this goal, the total scatter factors, tissue maximum, and off-axis ratios were measured with a stereotactic field diode for 4.0-, 10.0-, and 20.0-mm circular collimators. The irradiation was performed with a Novalis® linear accelerator using a 6-MV photon beam. The detector-specific correction factors were calculated and applied to the experimental dosimetry data for in-depth and off-axis locations. The corrected and uncorrected dosimetry data were used to commission a treatment planning system for radiosurgery planning. Various plans were calculated with simulated lesions using the uncorrected and corrected dosimetry. The resulting dose calculations were compared using the gamma index test with several criteria. The results of this work presented important conclusions for the use of detector-specific beam correction factors ([Formula: see text] in a treatment planning system. The use of [Formula: see text] for total scatter factors has an important impact on monitor unit calculation. On the contrary, the use of [Formula: see text] for tissue-maximum and off-axis ratios has not an important impact on the dose distribution calculation by the treatment planning system. This conclusion is only valid for the combination of treatment planning system, detector, and correction factors used in this work; however, this technique can be applied to other treatment planning systems, detectors, and correction factors.

Cloning and expression of hepatic synaptotagmin 1 in mouse.

PubMed

Sancho-Knapik, Sara; Guillén, Natalia; Osada, Jesús

2015-05-15

Mouse hepatic synaptotagmin 1 (SYT1) cDNA was cloned, characterized and compared to the brain one. The hepatic transcript was 1807 bp in length, smaller than the brain, and only encoded by 9 of 11 gene exons. In this regard, 5'-and 3'-untranslated regions were 66 and 476 bp, respectively; the open reading frame of 1266 bp codified for a protein of 421 amino acids, identical to the brain, with a predicted molecular mass of 47.4 kDa and highly conserved across different species. Immunoblotting of protein showed two isoforms of higher molecular masses than the theoretical prediction based on amino acid sequence suggesting posttranslational modifications. Subcellular distribution of protein isoforms corresponded to plasma membrane, lysosomes and microsomes and was identical between the brain and liver. Nonetheless, the highest molecular weight isoform was smaller in the liver, irrespective of subcellular location. Quantitative mRNA tissue distribution showed that it was widely expressed and that the highest values corresponded to the brain, followed by the liver, spleen, abdominal fat, intestine and skeletal muscle. These findings indicate tissue-specific splicing of the gene and posttranslational modification and the variation in expression in the different tissues might suggest a different requirement of SYT1 for the specific function in each organ. Copyright © 2015 Elsevier B.V. All rights reserved.

Distribution of glucosinolates and sulphur-rich cells in roots of field-grown canola (Brassica napus).

PubMed

McCully, Margaret E; Miller, Celia; Sprague, Susan J; Huang, Cheng X; Kirkegaard, John A

2008-01-01

To investigate the role played by the distribution pattern of glucosinolates (GSLs) in root systems in the release of biocides to the rhizosphere, GSLs have been localized, for the first time, to specific regions and cells in field-grown roots. GSL concentrations in separated tissues of canola (Brassica napus) were determined by chemical analysis, and cell-specific concentrations by extrapolation from sulphur concentrations obtained by quantitative cryo-analytical scanning electron microscopy (SEM). In roots with secondary growth, GSL concentrations in the outer secondary tissues were up to 5x those of the inner core. The highest GSL concentrations (from sulphur measurements) were in two cell layers just under the outermost periderm layer, with up to 100x published concentrations for whole roots. Primary tissues had negligible GSL. Release and renewal of the peripheral GSLs is probably a normal developmental process as secondary thickening continues and surface cells senesce, accounting for published observations that intact roots release GSLs and their biocide hydrolosates to the rhizosphere. Absence of myrosin idioblasts close to the root surface suggests that GSLs released developmentally are hydrolysed by myrosinase in the rhizosphere, ensuring a continuous localized source of biotoxic hydrolysates which can deter soil-borne pests, and influence microbial populations associated with long-lived components of the root system.

Bioimaging of metals in brain tissue by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and metallomics.

PubMed

Becker, J Sabine; Matusch, Andreas; Palm, Christoph; Salber, Dagmar; Morton, Kathryn A; Becker, J Susanne

2010-02-01

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been developed and established as an emerging technique in the generation of quantitative images of metal distributions in thin tissue sections of brain samples (such as human, rat and mouse brain), with applications in research related to neurodegenerative disorders. A new analytical protocol is described which includes sample preparation by cryo-cutting of thin tissue sections and matrix-matched laboratory standards, mass spectrometric measurements, data acquisition, and quantitative analysis. Specific examples of the bioimaging of metal distributions in normal rodent brains are provided. Differences to the normal were assessed in a Parkinson's disease and a stroke brain model. Furthermore, changes during normal aging were studied. Powerful analytical techniques are also required for the determination and characterization of metal-containing proteins within a large pool of proteins, e.g., after denaturing or non-denaturing electrophoretic separation of proteins in one-dimensional and two-dimensional gels. LA-ICP-MS can be employed to detect metalloproteins in protein bands or spots separated after gel electrophoresis. MALDI-MS can then be used to identify specific metal-containing proteins in these bands or spots. The combination of these techniques is described in the second section.

Tissue Specific Activation and Inactivation of the Neu Proto-Oncogene in Transgenic Mice Using Cre Recombinase

DTIC Science & Technology

2000-10-01

UNCLASSIFIED AD NUMBER ADB264584 NEW LIMITATION CHANGE TO Approved for public release, distribution unlimited FROM Distribution authorized to U.S...MAY RELATE TO THEM. LIMITED RIGHTS LEGEND Award Number: DAMD17-99-1-9285 Organization: McMaster University Those portions of the technical data...contained in this report marked as limited rights data shall not, without the written permission of the above contractor, be (a) released or disclosed outside

Experimental and theoretical investigation of intratumoral nanoparticle distribution to enhance magnetic nanoparticle hyperthermia

NASA Astrophysics Data System (ADS)

Attaluri, Anilchandra

Magnetic nanoparticles have gained prominence in recent years for use in clinical applications such as imaging, drug delivery, and hyperthermia. Magnetic nanoparticle hyperthermia is a minimally invasive and effective approach for confined heating in tumors with little collateral damage. One of the major problems in the field of magnetic nanoparticle hyperthermia is irregular heat distribution in tumors which caused repeatable heat distribution quite impossible. This causes under dosage in tumor area and overheating in normal tissue. In this study, we develop a unified approach to understand magnetic nanoparticle distribution and temperature elevations in gel and tumors. A microCT imaging system is first used to visualize and quantify nanoparticle distribution in both tumors and tissue equivalent phantom gels. The microCT based nanoparticle concentration is related to specific absorption rate (SAR) of the nanoparticles and is confirmed by heat distribution experiments in tissue equivalent phantom gels. An optimal infusion protocol is identified to generate controllable and repeatable nanoparticle distribution in tumors. In vivo animal experiments are performed to measure intratumoral temperature elevations in PC3 xenograft tumors implanted in mice during magnetic nanoparticle hyperthermia. The effect of nanofluid injection parameters on the resulted temperature distribution is studied. It shows that the tumor temperatures can be elevated above 50°C using very small amounts of ferrofluid with a relatively low magnetic field. Slower ferrofluid infusion rates result in smaller nanoparticle distribution volumes in the tumors, however, it gives the much required controllability and repeatability when compared to the higher infusion rates. More nanoparticles occupy a smaller volume in the vicinity of the injection site with slower infusion rates, causing higher temperature elevations in the tumors. Based on the microCT imaging analyses of nanoparticles in tumors, a mass transport model is developed to simulate nanoparticle convection and diffusion in tumors, heat-induced tumor structural changes, as well as nanoparticle re-distribution during nanoparticle hyperthermia procedures. The modeled thermal damage induced nanoparticle redistribution predicts a 20% increase in the radius of the spherical tissue region containing nanoparticles. The developed model has demonstrated the feasibility of enhancing nanoparticle dispersion from injection sites using targeted thermal damage.

Multicolor fluorescent intravital live microscopy (FILM) for surgical tumor resection in a mouse xenograft model.

PubMed

Thurber, Greg M; Figueiredo, Jose L; Weissleder, Ralph

2009-11-30

Complete surgical resection of neoplasia remains one of the most efficient tumor therapies. However, malignant cell clusters are often left behind during surgery due to the inability to visualize and differentiate them against host tissue. Here we establish the feasibility of multicolor fluorescent intravital live microscopy (FILM) where multiple cellular and/or unique tissue compartments are stained simultaneously and imaged in real time. Theoretical simulations of imaging probe localization were carried out for three agents with specificity for cancer cells, stromal host response, or vascular perfusion. This transport analysis gave insight into the probe pharmacokinetics and tissue distribution, facilitating the experimental design and allowing predictions to be made about the localization of the probes in other animal models and in the clinic. The imaging probes were administered systemically at optimal time points based on the simulations, and the multicolor FILM images obtained in vivo were then compared to conventional pathological sections. Our data show the feasibility of real time in vivo pathology at cellular resolution and molecular specificity with excellent agreement between intravital and traditional in vitro immunohistochemistry. Multicolor FILM is an accurate method for identifying malignant tissue and cells in vivo. The imaging probes distributed in a manner similar to predictions based on transport principles, and these models can be used to design future probes and experiments. FILM can provide critical real time feedback and should be a useful tool for more effective and complete cancer resection.

Neutron organ dose and the influence of adipose tissue

NASA Astrophysics Data System (ADS)

Simpkins, Robert Wayne

Neutron fluence to dose conversion coefficients have been assessed considering the influences of human adipose tissue. Monte Carlo code MCNP4C was used to simulate broad parallel beam monoenergetic neutrons ranging in energy from thermal to 10 MeV. Simulated Irradiations were conducted for standard irradiation geometries. The targets were on gender specific mathematical anthropomorphic phantoms modified to approximate human adipose tissue distributions. Dosimetric analysis compared adipose tissue influence against reference anthropomorphic phantom characteristics. Adipose Male and Post-Menopausal Female Phantoms were derived introducing interstitial adipose tissue to account for 22 and 27 kg additional body mass, respectively, each demonstrating a Body Mass Index (BMI) of 30. An Adipose Female Phantom was derived introducing specific subcutaneous adipose tissue accounting for 15 kg of additional body mass demonstrating a BMI of 26. Neutron dose was shielded in the superficial tissues; giving rise to secondary photons which dominated the effective dose for Incident energies less than 100 keV. Adipose tissue impact on the effective dose was a 25% reduction at the anterior-posterior incidence ranging to a 10% increase at the lateral incidences. Organ dose impacts were more distinctive; symmetrically situated organs demonstrated a 15% reduction at the anterior-posterior Incidence ranging to a 2% increase at the lateral incidences. Abdominal or asymmetrically situated organs demonstrated a 50% reduction at the anterior-posterior incidence ranging to a 25% increase at the lateral incidences.

Biological and mechanical interplay at the Macro- and Microscales Modulates the Cell-Niche Fate.

PubMed

Sarig, Udi; Sarig, Hadar; Gora, Aleksander; Krishnamoorthi, Muthu Kumar; Au-Yeung, Gigi Chi Ting; de-Berardinis, Elio; Chaw, Su Yin; Mhaisalkar, Priyadarshini; Bogireddi, Hanumakumar; Ramakrishna, Seeram; Boey, Freddy Yin Chiang; Venkatraman, Subbu S; Machluf, Marcelle

2018-03-02

Tissue development, regeneration, or de-novo tissue engineering in-vitro, are based on reciprocal cell-niche interactions. Early tissue formation mechanisms, however, remain largely unknown given complex in-vivo multifactoriality, and limited tools to effectively characterize and correlate specific micro-scaled bio-mechanical interplay. We developed a unique model system, based on decellularized porcine cardiac extracellular matrices (pcECMs)-as representative natural soft-tissue biomaterial-to study a spectrum of common cell-niche interactions. Model monocultures and 1:1 co-cultures on the pcECM of human umbilical vein endothelial cells (HUVECs) and human mesenchymal stem cells (hMSCs) were mechano-biologically characterized using macro- (Instron), and micro- (AFM) mechanical testing, histology, SEM and molecular biology aspects using RT-PCR arrays. The obtained data was analyzed using developed statistics, principal component and gene-set analyses tools. Our results indicated biomechanical cell-type dependency, bi-modal elasticity distributions at the micron cell-ECM interaction level, and corresponding differing gene expression profiles. We further show that hMSCs remodel the ECM, HUVECs enable ECM tissue-specific recognition, and their co-cultures synergistically contribute to tissue integration-mimicking conserved developmental pathways. We also suggest novel quantifiable measures as indicators of tissue assembly and integration. This work may benefit basic and translational research in materials science, developmental biology, tissue engineering, regenerative medicine and cancer biomechanics.

Tissue-Specific Fatty Acids Response to Different Diets in Common Carp (Cyprinus carpio L.)

PubMed Central

Böhm, Markus; Schultz, Sebastian; Koussoroplis, Apostolos-Manuel; Kainz, Martin J.

2014-01-01

Fish depend on dietary fatty acids (FA) to support their physiological condition and health. Exploring the FA distribution in common carp (Cyprinus carpio), one of the world's most consumed freshwater fish, is important to understand how and where FA of different sources are allocated. We investigated diet effects on the composition of polar and neutral lipid fatty acids (PLFA and NLFA, respectively) in eight different tissues (dorsal and ventral muscle, heart, kidney, intestine, eyes, liver and adipose tissue) of common carp. Two-year old carp were exposed to three diet sources (i.e., zooplankton, zooplankton plus supplementary feeds containing vegetable, VO, or fish oil, FO) with different FA composition. The PLFA and NLFA response was clearly tissue-specific after 210 days of feeding on different diets. PLFA were generally rich in omega-3 polyunsaturated FA and only marginally influenced by dietary FA, whereas the NLFA composition strongly reflected dietary FA profiles. However, the NLFA composition in carp tissues varied considerably at low NLFA mass ratios, suggesting that carp is able to regulate the NLFA composition and thus FA quality in its tissues when NLFA contents are low. Finally, this study shows that FO were 3X more retained than VO as NLFA particularly in muscle tissues, indicating that higher nutritional quality feeds are selectively allocated into tissues and thus available for human consumption. PMID:24733499

An image-based skeletal dosimetry model for the ICRP reference adult male—internal electron sources

NASA Astrophysics Data System (ADS)

Hough, Matthew; Johnson, Perry; Rajon, Didier; Jokisch, Derek; Lee, Choonsik; Bolch, Wesley

2011-04-01

In this study, a comprehensive electron dosimetry model of the adult male skeletal tissues is presented. The model is constructed using the University of Florida adult male hybrid phantom of Lee et al (2010 Phys. Med. Biol. 55 339-63) and the EGSnrc-based Paired Image Radiation Transport code of Shah et al (2005 J. Nucl. Med. 46 344-53). Target tissues include the active bone marrow, associated with radiogenic leukemia, and total shallow marrow, associated with radiogenic bone cancer. Monoenergetic electron emissions are considered over the energy range 1 keV to 10 MeV for the following sources: bone marrow (active and inactive), trabecular bone (surfaces and volumes), and cortical bone (surfaces and volumes). Specific absorbed fractions are computed according to the MIRD schema, and are given as skeletal-averaged values in the paper with site-specific values reported in both tabular and graphical format in an electronic annex available from http://stacks.iop.org/0031-9155/56/2309/mmedia. The distribution of cortical bone and spongiosa at the macroscopic dimensions of the phantom, as well as the distribution of trabecular bone and marrow tissues at the microscopic dimensions of the phantom, is imposed through detailed analyses of whole-body ex vivo CT images (1 mm resolution) and spongiosa-specific ex vivo microCT images (30 µm resolution), respectively, taken from a 40 year male cadaver. The method utilized in this work includes: (1) explicit accounting for changes in marrow self-dose with variations in marrow cellularity, (2) explicit accounting for electron escape from spongiosa, (3) explicit consideration of spongiosa cross-fire from cortical bone, and (4) explicit consideration of the ICRP's change in the surrogate tissue region defining the location of the osteoprogenitor cells (from a 10 µm endosteal layer covering the trabecular and cortical surfaces to a 50 µm shallow marrow layer covering trabecular and medullary cavity surfaces). Skeletal-averaged values of absorbed fraction in the present model are noted to be very compatible with those weighted by the skeletal tissue distributions found in the ICRP Publication 110 adult male and female voxel phantoms, but are in many cases incompatible with values used in current and widely implemented internal dosimetry software.

Vitamin C in Health and Disease: Its Role in the Metabolism of Cells and Redox State in the Brain.

PubMed

Figueroa-Méndez, Rodrigo; Rivas-Arancibia, Selva

2015-01-01

Ever since Linus Pauling published his studies, the effects of vitamin C have been surrounded by contradictory results. This may be because its effects depend on a number of factors such as the redox state of the body, the dose used, and also on the tissue metabolism. This review deals with vitamin C pharmacokinetics and its participation in neurophysiological processes, as well as its role in the maintenance of redox balance. The distribution and the concentration of vitamin C in the organs depend on the ascorbate requirements of each and on the tissue distribution of sodium-dependent vitamin C transporter 1 and 2 (SVCT1 and SVCT2). This determines the specific distribution pattern of vitamin C in the body. Vitamin C is involved in the physiology of the nervous system, including the support and the structure of the neurons, the processes of differentiation, maturation, and neuronal survival; the synthesis of catecholamine, and the modulation of neurotransmission. This antioxidant interacts with self-recycling mechanisms, including its participation in the endogenous antioxidant system. We conclude that the pharmacokinetic properties of ascorbate are related to the redox state and its functions and effects in tissues.

Vitamin C in Health and Disease: Its Role in the Metabolism of Cells and Redox State in the Brain

PubMed Central

Figueroa-Méndez, Rodrigo; Rivas-Arancibia, Selva

2015-01-01

Ever since Linus Pauling published his studies, the effects of vitamin C have been surrounded by contradictory results. This may be because its effects depend on a number of factors such as the redox state of the body, the dose used, and also on the tissue metabolism. This review deals with vitamin C pharmacokinetics and its participation in neurophysiological processes, as well as its role in the maintenance of redox balance. The distribution and the concentration of vitamin C in the organs depend on the ascorbate requirements of each and on the tissue distribution of sodium-dependent vitamin C transporter 1 and 2 (SVCT1 and SVCT2). This determines the specific distribution pattern of vitamin C in the body. Vitamin C is involved in the physiology of the nervous system, including the support and the structure of the neurons, the processes of differentiation, maturation, and neuronal survival; the synthesis of catecholamine, and the modulation of neurotransmission. This antioxidant interacts with self-recycling mechanisms, including its participation in the endogenous antioxidant system. We conclude that the pharmacokinetic properties of ascorbate are related to the redox state and its functions and effects in tissues. PMID:26779027

In ovo uptake, metabolism, and tissue-specific distribution of chiral PCBs and PBDEs in developing chicken embryos

PubMed Central

Li, Zong-Rui; Luo, Xiao-Jun; Huang, Li-Qian; Mai, Bi-Xian

2016-01-01

Fertilized chicken eggs were injected with environmental doses of 4 chiral polychlorinated biphenyls (PCBs) and 8 polybrominated biphenyl ethers (PBDEs) to investigate their uptake, metabolism in the embryo, and distribution in the neonate chicken. PCB95 uptake was the most efficient (80%) whereas BDE209 was the least (56%). Embryos metabolized approximately 52% of the PCBs absorbed. Though some degree of metabolism in the first 18 days, most of the PCBs and PBDEs was metabolized in the last three days, when BDE85, 99, 153, and 209 decrease by 11–37%. Enantioselective metabolism of the (+) enantiomers of PCB95, 149, and 132 and the (−) enantiomer of PCB91 was observed. The enantioselective reactivity was higher with the two penta-PCBs than the two tetra-PCBs. Liver, exhibited high affinity for high lipophilic chemicals, enrich all chemicals that was deflected in other tissues except for some special chemicals in a given tissues. Lipid composition, time of organ formation, and metabolism contribute to the distribution of chemicals in the neonate chicken. The result of this study will improve our understanding on the fate and potential adverse effects of PCBs and PBDEs in the neonate chicken. PMID:27819361

HPASubC: A suite of tools for user subclassification of human protein atlas tissue images.

PubMed

Cornish, Toby C; Chakravarti, Aravinda; Kapoor, Ashish; Halushka, Marc K

2015-01-01

The human protein atlas (HPA) is a powerful proteomic tool for visualizing the distribution of protein expression across most human tissues and many common malignancies. The HPA includes immunohistochemically-stained images from tissue microarrays (TMAs) that cover 48 tissue types and 20 common malignancies. The TMA data are used to provide expression information at the tissue, cellular, and occasionally, subcellular level. The HPA also provides subcellular data from confocal immunofluorescence data on three cell lines. Despite the availability of localization data, many unique patterns of cellular and subcellular expression are not documented. To get at this more granular data, we have developed a suite of Python scripts, HPASubC, to aid in subcellular, and cell-type specific classification of HPA images. This method allows the user to download and optimize specific HPA TMA images for review. Then, using a playstation-style video game controller, a trained observer can rapidly step through 10's of 1000's of images to identify patterns of interest. We have successfully used this method to identify 703 endothelial cell (EC) and/or smooth muscle cell (SMCs) specific proteins discovered within 49,200 heart TMA images. This list will assist us in subdividing cardiac gene or protein array data into expression by one of the predominant cell types of the myocardium: Myocytes, SMCs or ECs. The opportunity to further characterize unique staining patterns across a range of human tissues and malignancies will accelerate our understanding of disease processes and point to novel markers for tissue evaluation in surgical pathology.

HPASubC: A suite of tools for user subclassification of human protein atlas tissue images

PubMed Central

Cornish, Toby C.; Chakravarti, Aravinda; Kapoor, Ashish; Halushka, Marc K.

2015-01-01

Background: The human protein atlas (HPA) is a powerful proteomic tool for visualizing the distribution of protein expression across most human tissues and many common malignancies. The HPA includes immunohistochemically-stained images from tissue microarrays (TMAs) that cover 48 tissue types and 20 common malignancies. The TMA data are used to provide expression information at the tissue, cellular, and occasionally, subcellular level. The HPA also provides subcellular data from confocal immunofluorescence data on three cell lines. Despite the availability of localization data, many unique patterns of cellular and subcellular expression are not documented. Materials and Methods: To get at this more granular data, we have developed a suite of Python scripts, HPASubC, to aid in subcellular, and cell-type specific classification of HPA images. This method allows the user to download and optimize specific HPA TMA images for review. Then, using a playstation-style video game controller, a trained observer can rapidly step through 10's of 1000's of images to identify patterns of interest. Results: We have successfully used this method to identify 703 endothelial cell (EC) and/or smooth muscle cell (SMCs) specific proteins discovered within 49,200 heart TMA images. This list will assist us in subdividing cardiac gene or protein array data into expression by one of the predominant cell types of the myocardium: Myocytes, SMCs or ECs. Conclusions: The opportunity to further characterize unique staining patterns across a range of human tissues and malignancies will accelerate our understanding of disease processes and point to novel markers for tissue evaluation in surgical pathology. PMID:26167380

Tissue-specific in vivo genetic toxicity of nine polycyclic aromatic hydrocarbons assessed using the Muta™Mouse transgenic rodent assay

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

Long, Alexandra S., E-mail: alexandra.long@hc-sc.gc.ca; Mechanistic Studies Division, Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON; Lemieux, Christine L.

Test batteries to screen chemicals for mutagenic hazard include several endpoints regarded as effective for detecting genotoxic carcinogens. Traditional in vivo methods primarily examine clastogenic endpoints in haematopoietic tissues. Although this approach is effective for identifying systemically distributed clastogens, some mutagens may not induce clastogenic effects; moreover, genotoxic effects may be restricted to the site of contact and/or related tissues. An OECD test guideline for transgenic rodent (TGR) gene mutation assays was released in 2011, and the TGR assays permit assessment of mutagenicity in any tissue. This study assessed the responses of two genotoxicity endpoints following sub-chronic oral exposures ofmore » male Muta™Mouse to 9 carcinogenic polycyclic aromatic hydrocarbons (PAHs). Clastogenicity was assessed via induction of micronuclei in peripheral blood, and mutagenicity via induction of lacZ transgene mutations in bone marrow, glandular stomach, small intestine, liver, and lung. Additionally, the presence of bulky PAH-DNA adducts was examined. Five of the 9 PAHs elicited positive results across all endpoints in at least one tissue, and no PAHs were negative or equivocal across all endpoints. All PAHs were positive for lacZ mutations in at least one tissue (sensitivity = 100%), and for 8 PAHs, one or more initial sites of chemical contact (i.e., glandular stomach, liver, small intestine) yielded a greater response than bone marrow. Five PAHs were positive in the micronucleus assay (sensitivity = 56%). Furthermore, all PAHs produced DNA adducts in at least one tissue. The results demonstrate the utility of the TGR assay for mutagenicity assessment, especially for compounds that may not be systemically distributed. - Highlights: • The Muta™Mouse is a reliable tool for in vivo mutagenicity assessment of PAHs. • All 9 PAHs induced lacZ transgene mutations in small intestine. • Only 5 of 9 PAHs induced lacZ mutations and micronuclei in haematopoietic tissue. • Tissue-specific results are likely related to metabolism, repair, and proliferation. • For oral exposures, it is important to examine effects at the site-of-contact.« less

Effects of cyclic flexure on endothelial permeability and apoptosis in arterial segments perfused ex vivo.

PubMed

Van Epps, J Scott; Chew, Douglas W; Vorp, David A

2009-10-01

Certain arteries (e.g., coronary, femoral, etc.) are exposed to cyclic flexure due to their tethering to surrounding tissue beds. It is believed that such stimuli result in a spatially variable biomechanical stress distribution, which has been implicated as a key modulator of remodeling associated with atherosclerotic lesion localization. In this study we utilized a combined ex vivo experimental/computational methodology to address the hypothesis that local variations in shear and mural stress associated with cyclic flexure influence the distribution of early markers of atherogenesis. Bilateral porcine femoral arteries were surgically harvested and perfused ex vivo under pulsatile arterial conditions. One of the paired vessels was exposed to cyclic flexure (0-0.7 cm(-1)) at 1 Hz for 12 h. During the last hour, the perfusate was supplemented with Evan's blue dye-labeled albumin. A custom tissue processing protocol was used to determine the spatial distribution of endothelial permeability, apoptosis, and proliferation. Finite element and computational fluid dynamics techniques were used to determine the mural and shear stress distributions, respectively, for each perfused segment. Biological data obtained experimentally and mechanical stress data estimated computationally were combined in an experiment-specific manner using multiple linear regression analyses. Arterial segments exposed to cyclic flexure had significant increases in intimal and medial apoptosis (3.42+/-1.02 fold, p=0.029) with concomitant increases in permeability (1.14+/-0.04 fold, p=0.026). Regression analyses revealed specific mural stress measures including circumferential stress at systole, and longitudinal pulse stress were quantitatively correlated with the distribution of permeability and apoptosis. The results demonstrated that local variation in mechanical stress in arterial segments subjected to cyclic flexure indeed influence the extent and spatial distribution of the early atherogenic markers. In addition, the importance of including mural stresses in the investigation of vascular mechanopathobiology was highlighted. Specific example results were used to describe a potential mechanism by which systemic risk factors can lead to a heterogeneous disease.

Tracking in vivo migration and distribution of antigen-specific cytotoxic T lymphocytes by 5,6-carboxyfluorescein diacetate succinimidyl ester staining during cancer immunotherapy.

PubMed

Xu, Wei-li; Li, Suo-lin; Wen, Ming; Wen, Jun-ye; Han, Jie; Zhang, Hong-zhen; Gao, Fei; Cai, Jian-hui

2013-08-01

Killing of targeted tumors during adoptive cell transfer therapy is associated with cytotoxic T lymphocyte (CTL) numbers, immunophenotype, tumor-specificity, and in vivo residence time, migration, and distribution. Therefore, tracing in vivo persistence, migration, and distribution of CTLs is important for cancer immunotherapy. Optimal staining concentration for CTL proliferation was determined by cell counting kit-8 (CCK-8) assay and killing efficiencies of CTLs or carboxyfluorescein diacetate succinimidyl ester (CFSE)-labeled melanoma antigen-specific cytotoxic T lymphocytes (CFSE-CTLs) for malignant melanoma cells in vitro were compared. Additionally, CFSE-CTLs were intravenously transfused to mice receiving B16 melanoma, and their residence time, migration, and distribution in vivo were observed by measuring fluorescence intensities of CFSE-CTLs per gram of tissue (%FI/g) in various tissues and analyzing tumor/non-tumor (T/NT) values. Anti-tumor effects of transferred CTLs and correlation between %FI/g and D-value of tumor size were analyzed. Five-micromolar CFSE was optimal for labeling CTLs with minimal cytotoxicity. No significant difference occurred between CTLs and CFSE-CTLs for tumor cell killing (P = 0.849) or interleukin-2 (P = 0.318) and interferon-γ (P = 0.201) levels. Distribution of CTLs in vivo varied with time. A negative correlation between %FI/g in tumors and D-value of tumor sizes by Spearman correlation analysis was observed. CTLs were recruited to and killed tumors from 6 hours to 3 days after cell infusion. CTLs were observed up to three weeks later in the tumor, liver, kidneys, and spleen; this was related to the abundant blood supply or the nature of immune organs. CCK-8 assay is a novel method to select optimal CFSE staining concentrations. Fluorescence intensity of transferred CTLs reflects their killing efficiency of tumors. CFSE fluorescent markers can trace in vivo CTL persistence, migration, and distribution because of its stability, long half-life, and low toxicity.

Immunocytochemical methods to study the distribution of Orientia tsutsugamushi in Leptotrombidium (Acari: Trombiculidae) chiggers.

PubMed

Myint, K S; Linthicum, K J; Tanskul, P; Lerdthusnee, K; Vaughn, D W; Manomuth, C; Mongkolsirichaikul, D; Hansukjariya, P; Hastriter, M W

1998-07-01

Immunocytochemical methods were developed and tested for their ability to detect the distribution of Orientia tsutsugamushi in paraffin sections of adult chiggers (Leptotrombidium imphalum Vercammen-Grandjean & Langston). Rickettsial antigen was detected by application of a simple direct or amplified immunocytochemistry procedure and an indirect immunofluorescent procedure. In the direct procedure alkaline phosphatase conjugation to the mouse polyclonal antibody to the Karp strain was followed by the HistoMark Red test system to detect rickettsial antigen. The amplification procedure used a similar method but used an unlabeled primary antibody followed by secondary biotinylated antimouse IgG, streptavidin-alkaline phosphatase, and the HistoMark Red test system. The immunofluorescent procedure included a biotinylated secondary antibody followed by addition of a streptavidin-FITC conjugate. Specific tissue tropisms in infected chiggers were observed in the salivary glands, nervous tissue, and ovaries of adult female mites in all procedures; however, nonspecific fluorescence of the chigger limited definitive identification of tissue tropisms with the indirect immunofluorescent procedure.

Direct tissue analysis by matrix-assisted laser desorption ionization mass spectrometry: application to kidney biology.

PubMed

Herring, Kristen D; Oppenheimer, Stacey R; Caprioli, Richard M

2007-11-01

Direct tissue analysis using matrix-assisted laser desorption ionization mass spectrometry (MALDI MS) provides in situ molecular analysis of a wide variety of biological molecules including xenobiotics. This technology allows measurement of these species in their native biological environment without the use of target-specific reagents such as antibodies. It can be used to profile discrete cellular regions and obtain region-specific images, providing information on the relative abundance and spatial distribution of proteins, peptides, lipids, and drugs. In this article, we report the sample preparation, MS data acquisition and analysis, and protein identification methodologies used in our laboratory for profiling/imaging MS and how this has been applied to kidney disease and toxicity.

Coherent light depolarization by multiple scattering media and tissues: some fundamentals and applications

NASA Astrophysics Data System (ADS)

Zimnyakov, Dmitry A.; Tuchin, Valery V.; Yodh, Arjun G.; Mishin, Alexey A.; Peretochkin, Igor S.

1998-04-01

Relationships between decorrelation and depolarization of coherent light scattered by disordered media are examined by using the conception of the photon paths distribution functions. Analysis of behavior of the autocorrelation functions of the scattered field fluctuations and their polarization properties allows us to introduce generalized parameter of scattering media such as specific correlation time. Determination of specific correlation time has been carried out for phantom scattering media (water suspensions of polystyrene spheres). Results of statistical, correlation and polarization analysis of static and dynamic speckle patterns carried out in the experiments with human sclera with artificially controlled optical transmittance are presented. Some possibilities of applications of such polarization- correlation technique for monitoring and visualization of non- single scattering tissue structures are discussed.

Tissue-specific programming of memory CD8 T cell subsets impacts protection against lethal respiratory virus infection

PubMed Central

Tahiliani, Vikas

2016-01-01

How tissue-specific anatomical distribution and phenotypic specialization are linked to protective efficacy of memory T cells against reinfection is unclear. Here, we show that lung environmental cues program recently recruited central-like memory cells with migratory potentials for their tissue-specific functions during lethal respiratory virus infection. After entering the lung, some central-like cells retain their original CD27hiCXCR3hi phenotype, enabling them to localize near the infected bronchiolar epithelium and airway lumen to function as the first line of defense against pathogen encounter. Others, in response to local cytokine triggers, undergo a secondary program of differentiation that leads to the loss of CXCR3, migration arrest, and clustering within peribronchoarterial areas and in interalveolar septa. Here, the immune system adapts its response to prevent systemic viral dissemination and mortality. These results reveal the striking and unexpected spatial organization of central- versus effector-like memory cells within the lung and how cooperation between these two subsets contributes to host defense. PMID:27879287

Distribution of keratin and associated proteins in the epidermis of monotreme, marsupial, and placental mammals.

PubMed

Alibardi, Lorenzo; Maderson, Paul F A

2003-10-01

The expression of acidic and basic keratins, and of some keratinization marker proteins such as filaggrin, loricrin, involucrin, and trichohyalin, is known for the epidermis of only a few eutherian species. Using light and high-resolution immunocytochemistry, the presence of these proteins has been studied in two monotreme and five marsupial species and compared to that in eutherians. In both monotreme and marsupial epidermis lamellar bodies occur in the upper spinosus and granular layers. Development of the granular layer varies between species and regionally within species. There is great interspecific variation in the size (0.1-3.0 microm) of keratohyalin granules (KHGs) associated with production of orthokeratotic corneous tissues. Those skin regions lacking hairs (platypus web), or showing reduced pelage density (wombat) have, respectively, minute or indiscernible KHGs, associated with patchy, or total, parakeratosis. Ultrastructural analysis shows that monotreme and marsupial KHGs comprise irregular coarse filaments of 25-40 nm that contact keratin filaments. Except for parakeratotic tissues of platypus web, distribution of acidic and basic proteins in monotreme and marsupial epidermis as revealed by anti-keratin antibodies AE1, AE2, and AE3 resembles that of eutherian epidermis. Antibodies against human or rat filaggrins have little or no cross-reactivity with epidermal proteins of other mammals: only sparse areas of wombat and rabbit epidermis show a weak immunofluorescence in transitional cells and in the deepest corneous tissues. Of the available, eutherian-derived antibodies, that against involucrin shows no cross-reactivity with any monotreme and marsupial epidermal tissues and that against trichohyalin cross-reacts only with cells in the inner root sheath and medulla of hairs. These results suggest that if involucrin and trichohyalin are present throughout noneutherian epidermis, they may have species-specific molecular structures. By contrast, eutherian-derived anti-loricrin antibodies show a weak to intense cross-reactivity to KHGs and corneous tissues of both orthokeratotic and parakeratotic epidermis in monotremes and marsupials. High-resolution immunogold analysis of loricrin distribution in immature keratinocytes of platypus parakeratotic web epidermis identifies labeled areas of round or irregular, electron-pale granules within the denser keratohyalin component and keratin network. In the deepest mature tissues, loricrin-like labeling is diffuse throughout the cytoplasm, so that cells lack the preferential distribution of loricrin along the corneous envelope that characterizes mature eutherian keratinocytes. Thus, the irregular distribution of loricrin in platypus parakeratotic tissues more resembles that which has been described for reptilian and avian keratinocytes. These observations on the noneutherian epidermis show that a stratum granulosum is present to different degrees, even discontinuous within one tissue, so that parakeratotic and orthokeratotic areas may alternate: this might imply that parakeratotic monotreme epidermis reflects the primitive pattern of amniote alpha-keratogenesis. Absent from anamniote epidermis and all sauropsid beta-keratogenic tissues, the ubiquitous presence of a loricrin-like protein as a major component of other amniote corneous tissues suggests that this is a primitive feature of amniote alpha-keratogenesis. The apparent lack of specific regionalization of loricin near the plasma membranes of monotreme keratinocytes could be an artifactual result of the immunofluorescence technique employed, or there may be masking of the antigenicity of loricrin-like proteins once they are incorporated into the corneous envelope. Nevertheless, the mechanism of redistribution of such proteins during maturation of monotreme keratinocytes is different from, perhaps more primitive, or less specialized, than that in the epidermis of eutherian mammals. Copyright 2003 Wiley-Liss, Inc.

[Preparation and identification of the polyclonal antibody against ATRX-C2193-2492].

PubMed

Tang, Shuangyang; Liu, Zhimin; Li, Ranhui; Chen, Yan; Zhao, Lanhua; Shen, Haiyan; Wan, Yanping

2017-04-01

Objective To prepare the polyclonal antibody against human alpha thalassemia/mental retardation syndrome X-linked (ATRX) C-terminal and study the distribution and expression of ATRX protein in human cervical cancer tissues. Methods The antiserum was obtained from the BALB/c mice immunized with 6 His-ATRX-C 2193-2492 protein and then purified by the saturated ammonium sulfate precipitation and affinity chromatography. The titer of anti-ATRX polyclonal antibody was determined by ELISA. Its specificity was identified by SDS-PAGE analysis and Western blotting. The expression and location of ATRX in human cervical tissues were analyzed by immunohistochemistry. Results The titer of the polyclonal antibody against 6 His-ATRX-C 2193-2492 protein was about 1:12 800. The antibody could recognize 6 His-ATRX-C 2193-2492 protein specifically. With the polyclonal antibody, the target protein was found mainly in the nucleus of para-carcinoma tissues, and it was also expressed in the nucleus of cervical cancer tissue cells, but the expression in the latter was obviously lower. Conclusion The polyclonal antibody against 6 His-ATRX-C 2193-2492 protein has been produced successfully and used to detect ATRX protein in human cervical cancer tissues.

A Monte Carlo investigation of lung brachytherapy treatment planning

NASA Astrophysics Data System (ADS)

Sutherland, J. G. H.; Furutani, K. M.; Thomson, R. M.

2013-07-01

Iodine-125 (125I) and Caesium-131 (131Cs) brachytherapy have been used in conjunction with sublobar resection to reduce the local recurrence of stage I non-small cell lung cancer compared with resection alone. Treatment planning for this procedure is typically performed using only a seed activity nomogram or look-up table to determine seed strand spacing for the implanted mesh. Since the post-implant seed geometry is difficult to predict, the nomogram is calculated using the TG-43 formalism for seeds in a planar geometry. In this work, the EGSnrc user-code BrachyDose is used to recalculate nomograms using a variety of tissue models for 125I and 131Cs seeds. Calculated prescription doses are compared to those calculated using TG-43. Additionally, patient CT and contour data are used to generate virtual implants to study the effects that post-implant deformation and patient-specific tissue heterogeneity have on perturbing nomogram-derived dose distributions. Differences of up to 25% in calculated prescription dose are found between TG-43 and Monte Carlo calculations with the TG-43 formalism underestimating prescription doses in general. Differences between the TG-43 formalism and Monte Carlo calculated prescription doses are greater for 125I than for 131Cs seeds. Dose distributions are found to change significantly based on implant deformation and tissues surrounding implants for patient-specific virtual implants. Results suggest that accounting for seed grid deformation and the effects of non-water media, at least approximately, are likely required to reliably predict dose distributions in lung brachytherapy patients.

DNA methylation map in circulating leukocytes mirrors subcutaneous adipose tissue methylation pattern: a genome-wide analysis from non-obese and obese patients

PubMed Central

Crujeiras, A. B.; Diaz-Lagares, A.; Sandoval, J.; Milagro, F. I.; Navas-Carretero, S.; Carreira, M. C.; Gomez, A.; Hervas, D.; Monteiro, M. P.; Casanueva, F. F.; Esteller, M.; Martinez, J. A.

2017-01-01

The characterization of the epigenetic changes within the obesity-related adipose tissue will provide new insights to understand this metabolic disorder, but adipose tissue is not easy to sample in population-based studies. We aimed to evaluate the capacity of circulating leukocytes to reflect the adipose tissue-specific DNA methylation status of obesity susceptibility. DNA samples isolated from subcutaneous adipose tissue and circulating leukocytes were hybridized in the Infinium HumanMethylation 450 BeadChip. Data were compared between samples from obese (n = 45) and non-obese (n = 8–10) patients by Wilcoxon-rank test, unadjusted for cell type distributions. A global hypomethylation of the differentially methylated CpG sites (DMCpGs) was observed in the obese subcutaneous adipose tissue and leukocytes. The overlap analysis yielded a number of genes mapped by the common DMCpGs that were identified to reflect the obesity state in the leukocytes. Specifically, the methylation levels of FGFRL1, NCAPH2, PNKD and SMAD3 exhibited excellent and statistically significant efficiencies in the discrimination of obesity from non-obesity status (AUC > 0.80; p < 0.05) and a great correlation between both tissues. Therefore, the current study provided new and valuable DNA methylation biomarkers of obesity-related adipose tissue pathogenesis through peripheral blood analysis, an easily accessible and minimally invasive biological material instead of adipose tissue. PMID:28211912

Metabolism of defined structured triglyceride particles compared to mixtures of medium and long chain triglycerides intravenously infused in dogs.

PubMed

Simoens, Ch; Deckelbaum, R J; Carpentier, Y A

2004-08-01

The present study aimed to determine whether including medium-chain fatty acids (MCFA) in specifically designed structured triglycerides (STG) with a MCFA in sn-1 and sn-3 positions and a long-chain (LC) FA in sn-2 position (MLM) would lead to different effects on plasma lipids and FA distribution into plasma and tissue lipids by comparison to a mixture of separate MCT and LCT molecules (MMM/LLL). The fatty acid (FA) composition was comparable in both lipid emulsions. Lipids were infused over 9h daily, in 2 groups of dogs (n = 6 each), for 28 days as a major component (55% of the non-protein energy intake) of total parenteral nutrition (TPN). Blood samples were obtained on specific days, before starting and just before stopping TPN. The concentration of plasma lipids was measured before starting and before stopping TPN on days 1, 2, 3, 4, 5, 8, 10, 12, 16 and 28. Biopsies were obtained from liver, muscle and adipose tissue 15 days before starting, and again on the day following cessation of TPN. In addition, the spleen was removed after the TPN period. FA composition in plasma and tissue lipids was analysed by gas liquid chromatography in different lipid components of plasma and tissues. No differences in either safety or tolerance parameters were detected between both lipid preparations. A lower rise of plasma TG (P < 0.05) was observed during MLM infusion, indicating a faster elimination rate of MLM vs MMM/LLL emulsion. In spite of the differences of TG molecules which would be assumed to affect the site of FA delivery and metabolic fate, FA distribution in phospholipids (PL) of hepatic and extrahepatic tissues did not substantially differ between both emulsions. Copyright 2003 Elsevier Ltd.

The tissue bank at the Instituto Nacional de Investigaciones Nucleares: ISO 9001:2000 certification of its quality management system.

PubMed

Martínez-Pardo, María Esther; Mariano-Magaña, David

2007-01-01

Tissue banking is a complex operation concerned with the organisation and coordination of all the steps, that is, from donor selection up to storage and distribution of the final products for therapeutic, diagnostic, instruction and research purposes. An appropriate quality framework should be established in order to cover all the specific methodology as well as the general aspects of quality management, such as research and development, design, instruction and training, specific documentation, traceability, corrective action, client satisfaction, and the like. Such a framework can be obtained by developing a quality management system (QMS) in accordance with a suitable international standard: ISO 9001:2000. This paper presents the implementation process of the tissue bank QMS at the Instituto Nacional de Investigaciones Nucleares in Mexico. The objective of the paper is to share the experience gained by the tissue bank personnel [radiosterilised tissue bank (BTR)] at the Instituto Nacional de Investigaciones Nucleares (ININ, National Institute of Nuclear Research), during implementation of the ISO 9001:2000 certification process. At present, the quality management system (QMS) of ININ also complies with the Mexican standard NMX-CC-9001:2000. The scope of this QMS is Research, Development and Processing of Biological Tissues Sterilised by Gamma Radiation, among others.

Applications and Emerging Trends of Hyaluronic Acid in Tissue Engineering, as a Dermal Filler, and in Osteoarthritis Treatment

PubMed Central

Fakhari, Amir; Berkland, Cory

2013-01-01

Hyaluronic acid (HA) is a naturally occurring biodegradable polymer with a variety of applications in medicine including scaffolding for tissue engineering, dermatological fillers, and viscosupplementation for osteoarthritis treatment. HA is available in most connective tissues in body fluids such as synovial fluid and the vitreous humor of the eye. HA is responsible for several structural properties of tissues as a component of extracellular matrix (ECM) and is involved in cellular signaling. Degradation of HA is a step-wise process that can occur via enzymatic or non-enzymatic reactions. A reduction in HA mass or molecular weight via degradation or slowing of synthesis affects physical and chemical properties such as tissue volume, viscosity, and elasticity. This review addresses the distribution, turnover, and tissue-specific properties of HA. This information is used as context for considering recent products and strategies for modifying the viscoelastic properties of HA in tissue engineering, as a dermal filler, and in osteoarthritis treatment. PMID:23507088

The Collagen Family

PubMed Central

Ricard-Blum, Sylvie

2011-01-01

Collagens are the most abundant proteins in mammals. The collagen family comprises 28 members that contain at least one triple-helical domain. Collagens are deposited in the extracellular matrix where most of them form supramolecular assemblies. Four collagens are type II membrane proteins that also exist in a soluble form released from the cell surface by shedding. Collagens play structural roles and contribute to mechanical properties, organization, and shape of tissues. They interact with cells via several receptor families and regulate their proliferation, migration, and differentiation. Some collagens have a restricted tissue distribution and hence specific biological functions. PMID:21421911

Malate dehydrogenase isozymes in the longnose dace, Rhinichthys cataractae.

PubMed

Starzyk, R M; Merritt, R B

1980-08-01

The interspecies homology of dace supernatant (A2,AB,B2) and mitochondrial (C2) malate dehydrogenase isozymes has been established through cell fractionation and tissue distribution studies. Isolated supernatant malate dehydrogenase (s-MDH) isozymes show significant differences in Michaelis constants for oxaloacetate and in pH optima. Shifts in s-MDH isozyme pH optima with temperature may result in immediate compensation for increase in ectotherm body pH with decrease in temperature, but duplicate s-MDH isozymes are probably maintained through selection for tissue specific regulation of metabolism.

Modelling the Transport of Nanoparticles under Blood Flow using an Agent-based Approach.

PubMed

Fullstone, Gavin; Wood, Jonathan; Holcombe, Mike; Battaglia, Giuseppe

2015-06-10

Blood-mediated nanoparticle delivery is a new and growing field in the development of therapeutics and diagnostics. Nanoparticle properties such as size, shape and surface chemistry can be controlled to improve their performance in biological systems. This enables modulation of immune system interactions, blood clearance profile and interaction with target cells, thereby aiding effective delivery of cargo within cells or tissues. Their ability to target and enter tissues from the blood is highly dependent on their behaviour under blood flow. Here we have produced an agent-based model of nanoparticle behaviour under blood flow in capillaries. We demonstrate that red blood cells are highly important for effective nanoparticle distribution within capillaries. Furthermore, we use this model to demonstrate how nanoparticle size can selectively target tumour tissue over normal tissue. We demonstrate that the polydispersity of nanoparticle populations is an important consideration in achieving optimal specificity and to avoid off-target effects. In future this model could be used for informing new nanoparticle design and to predict general and specific uptake properties under blood flow.

The specific absorption rate of tissues in rats exposed to electromagnetic plane waves in the frequency range of 0.05-5 GHz and SARwb in free-moving rats.

PubMed

Chen, Bingxin; Wang, Jiamin; Qi, Hongxin; Zhang, Jie; Chen, Shude; Wang, Xianghui

2017-03-01

As electromagnetic exposure experiments can only be performed on small animals, usually rats, research on the characteristics of specific absorption rate (SAR) distribution in the rat has received increasing interest. A series of calculations, which simulated the SAR in a male rat anatomical model exposed to electromagnetic plane waves ranging from 0.05 to 5 GHz with different incidence and polarization, were conducted. The whole-body-averaged SAR (SARwb) and the tissue-averaged SAR (SARavg) in 20 major tissues were determined. Results revealed that incidence has great impact on SAR in the rat at higher frequencies owing to the skin effect and the effect on SARavg in tissues is much more apparent than that on SARwb; while polarization plays an important role under lower frequencies. Not only the incidence, but also the polarization in the rat keeps changing when the rat is in free movement. Thus, this article discussed a convenient way to obtain relatively accurate SARwb in a free-moving rat.

Dexmedetomidine (12.5 μg/mL) improves tissue distribution, anesthetic action, and hemodynamic effects of lidocaine after palatal infiltration in rats.

PubMed

Akimoto, Takuma; Hashimoto, Shuichi; Sunada, Katsuhisa

2016-09-01

Dexmedetomidine hydrochloride (DEX) is a α2-adrenergic receptor agonist that causes vasoconstriction by acting on α2B-adrenergic receptors in peripheral blood vessels. The authors aimed to determine the influence of DEX on tissue distribution, anesthetic action, and hemodynamic effects of lidocaine in rats. The investigators injected indigo carmine-containing (14)C-labeled lidocaine hydrochloride (2 %) without and with 3.1, 12.5, or 50 μg/mL DEX or 10 μg/mL epinephrine into the right palatal mucosa mesial to the maxillary first molar of specific pathogen-free male Wistar rats. Autoradiography and liquid scintillation counting were performed to evaluate (14)C-labeled lidocaine concentrations in the palatal mucosa, maxillary bone, maxillary nerve, and peripheral blood. Somatosensory-evoked potentials were measured to analyze anesthetic action, and blood pressure and pulse rate were measured to compare hemodynamic effects. DEX extended the tissue distribution of lidocaine in a concentration-dependent manner. Lidocaine with 12.5 μg/mL DEX had similar blood peak arrival time and peak-to-peak amplitude as lidocaine with 10 μg/mL epinephrine, but it reduced pulse rate. The results of this study suggest that 12.5 μg/mL DEX improves tissue distribution, anesthetic action, and hemodynamic effects of lidocaine in rats. Therefore, 12.5 μg/mL DEX may be a suitable alternative to epinephrine in lidocaine formulations, especially for patients with ischemic heart disease and hypertension.

Stress, temperature, heart rate, and hibernating factors in hamsters. [pathophysiological conditions resulting from exposure to zero gravity

NASA Technical Reports Server (NTRS)

Musacchia, X. J.

1974-01-01

Pathophysiological conditions resulting from prolonged exposure to zero gravity, cabin constraint, altered ambient environment, whether it be noise, vibrations, high temperatures, or combinations of such factors, are studied in laboratory animals and applied to manned space flight. Results and plans for further study are presented. Specific topics covered include: thermoregulation and its role in reflecting stress and adaptation to the gravity free environment and cabin confinement with its altered circadian forcings; renal function and its measurement in electrolyte distribution and blood flow dynamics; gastronintestinal function and an assessment of altered absorptive capacity in the intestinal mucosa; and catecholamine metabolism in terms of distribution and turnover rates in specific tissues.

Uptake, tissue distribution and depuration of triclosan in the guppy Poecilia vivipara acclimated to freshwater.

PubMed

Escarrone, Ana Laura Venquiaruti; Caldas, Sergiane Souza; Primel, Ednei Gilberto; Martins, Samantha Eslava; Nery, Luiz Eduardo Maia

2016-08-01

The agent triclosan has been extensively used in different personal care products as a broad-spectrum antimicrobial and preservative agent. Due to its continuous release into the environment, including discharge via wastewater treatment plants, triclosan has been widely detected in aquatic environments. There is growing interest in improving the knowledge about the environmental fate of triclosan due to its possible bioaccumulation and the toxicity it may pose to organisms, such as fish and other non-target species. To investigate the distribution and bioconcentration of triclosan in fish, Poecilia vivipara was exposed to 0.2mgL(-1). Contents of triclosan in whole fish, brain, gonads, liver, muscle and gills were quantified by LC-MS/MS. When lipid normalised concentration was used, the liver exhibited the highest concentration followed by the gills, gonads, brain and muscle tissues. Bioconcentration was increased with time reaching a steady-state around 7-14days for most all tissues. After 24h depuration, triclosan concentrations declined >80% in all tissues except liver, in which triclosan takes longer to be depurated. These results not only clearly indicate that triclosan accumulated in P. vivipara, with tissue-specific bioconcentration factors (BCF) that ranged from 40.2 to 1025.4, but also show that the elimination of triclosan after transferring the fish to triclosan-free freshwater is rapid in all tissues. Copyright © 2016 Elsevier B.V. All rights reserved.

A Compressive Sensing Approach for Glioma Margin Delineation Using Mass Spectrometry

PubMed Central

Gholami, Behnood; Agar, Nathalie Y. R.; Jolesz, Ferenc A.; Haddad, Wassim M.; Tannenbaum, Allen R.

2013-01-01

Surgery, and specifically, tumor resection, is the primary treatment for most patients suffering from brain tumors. Medical imaging techniques, and in particular, magnetic resonance imaging are currently used in diagnosis as well as image-guided surgery procedures. However, studies show that computed tomography and magnetic resonance imaging fail to accurately identify the full extent of malignant brain tumors and their microscopic infiltration. Mass spectrometry is a well-known analytical technique used to identify molecules in a given sample based on their mass. In a recent study, it is proposed to use mass spectrometry as an intraoperative tool for discriminating tumor and non-tumor tissue. Integration of mass spectrometry with the resection module allows for tumor resection and immediate molecular analysis. In this paper, we propose a framework for tumor margin delineation using compressive sensing. Specifically, we show that the spatial distribution of tumor cell concentration can be efficiently reconstructed and updated using mass spectrometry information from the resected tissue. In addition, our proposed framework is model-free, and hence, requires no prior information of spatial distribution of the tumor cell concentration. PMID:22255629

Lung Motion Model Validation Experiments, Free-Breathing Tissue Densitometry, and Ventilation Mapping using Fast Helical CT Imaging

NASA Astrophysics Data System (ADS)

Dou, Hsiang-Tai

The uncertainties due to respiratory motion present significant challenges to accurate characterization of cancerous tissues both in terms of imaging and treatment. Currently available clinical lung imaging techniques are subject to inferior image quality and incorrect motion estimation, with consequences that can systematically impact the downstream treatment delivery and outcome. The main objective of this thesis is the development of the techniques of fast helical computed tomography (CT) imaging and deformable image registration for the radiotherapy applications in accurate breathing motion modeling, lung tissue density modeling and ventilation imaging. Fast helical CT scanning was performed on 64-slice CT scanner using the shortest available gantry rotation time and largest pitch value such that scanning of the thorax region amounts to just two seconds, which is less than typical breathing cycle in humans. The scanning was conducted under free breathing condition. Any portion of the lung anatomy undergoing such scanning protocol would be irradiated for only a quarter second, effectively removing any motion induced image artifacts. The resulting CT data were pristine volumetric images that record the lung tissue position and density in a fraction of the breathing cycle. Following our developed protocol, multiple fast helical CT scans were acquired to sample the tissue positions in different breathing states. To measure the tissue displacement, deformable image registration was performed that registers the non-reference images to the reference one. In modeling breathing motion, external breathing surrogate signal was recorded synchronously with the CT image slices. This allowed for the tissue-specific displacement to be modeled as parametrization of the recorded breathing signal using the 5D lung motion model. To assess the accuracy of the motion model in describing tissue position change, the model was used to simulate the original high-pitch helical CT scan geometries, employed as ground truth data. Image similarity between the simulated and ground truth scans was evaluated. The model validation experiments were conducted in a patient cohort of seventeen patients to assess the model robustness and inter-patient variation. The model error averaged over multiple tracked positions from several breathing cycles was found to be on the order of one millimeter. In modeling the density change under free breathing condition, the determinant of Jacobian matrix from the registration-derived deformation vector field yielded volume change information of the lung tissues. Correlation of the Jacobian values to the corresponding voxel Housfield units (HU) reveals that the density variation for the majority of lung tissues can be very well described by mass conservation relationship. Different tissue types were identified and separately modeled. Large trials of validation experiments were performed. The averaged deviation between the modeled and the reference lung density was 30 HU, which was estimated to be the background CT noise level. In characterizing the lung ventilation function, a novel method was developed to determine the extent of lung tissue volume change. Information on volume change was derived from the deformable image registration of the fast helical CT images in terms of Jacobian values with respect to a reference image. Assuming the multiple volume change measurements are independently and identically distributed, statistical formulation was derived to model ventilation distribution of each lung voxels and empirical minimum and maximum probability distribution of the Jacobian values was computed. Ventilation characteristic was evaluated as the difference of the expectation value from these extremal distributions. The resulting ventilation map was compared with an independently obtained ventilation image derived directly from the lung intensities and good correlation was found using statistical test. In addition, dynamic ventilation characterization was investigated by estimating the voxel-specific ventilation distribution. Ventilation maps were generated at different percentile levels using the tissue volume expansion metrics.

Autoradiographic localization of endothelin-1 binding sites in porcine skin

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

Zhao, Y.D.; Springall, D.R.; Wharton, J.

Autoradiographic techniques and {sup 125}I-labeled endothelin-1 were used to study the distribution of endothelin-1 binding sites in porcine skin. Specific endothelin-1 binding sites were localized to blood vessels (capillaries, deep cutaneous vascular plexus, arteries, and arterioles), the deep dermal and connective tissue sheath of hair follicles, sebaceous and sweat glands, and arrector pili muscle. Specific binding was inhibited by endothelin-2 and endothelin-3 as well as endothelin-1. Non-specific binding was found in the epidermis and the medulla of hair follicles. No binding was found in connective tissue or fat. These vascular binding sites may represent endothelin receptors, in keeping with themore » known cutaneous vasoconstrictor actions of the peptide. If all binding sites are receptors, the results suggest that endothelin could also regulate the function of sweat glands and may have trophic effects in the skin.« less

The tissue microarray data exchange specification: A community-based, open source tool for sharing tissue microarray data

PubMed Central

Berman, Jules J; Edgerton, Mary E; Friedman, Bruce A

2003-01-01

Background Tissue Microarrays (TMAs) allow researchers to examine hundreds of small tissue samples on a single glass slide. The information held in a single TMA slide may easily involve Gigabytes of data. To benefit from TMA technology, the scientific community needs an open source TMA data exchange specification that will convey all of the data in a TMA experiment in a format that is understandable to both humans and computers. A data exchange specification for TMAs allows researchers to submit their data to journals and to public data repositories and to share or merge data from different laboratories. In May 2001, the Association of Pathology Informatics (API) hosted the first in a series of four workshops, co-sponsored by the National Cancer Institute, to develop an open, community-supported TMA data exchange specification. Methods A draft tissue microarray data exchange specification was developed through workshop meetings. The first workshop confirmed community support for the effort and urged the creation of an open XML-based specification. This was to evolve in steps with approval for each step coming from the stakeholders in the user community during open workshops. By the fourth workshop, held October, 2002, a set of Common Data Elements (CDEs) was established as well as a basic strategy for organizing TMA data in self-describing XML documents. Results The TMA data exchange specification is a well-formed XML document with four required sections: 1) Header, containing the specification Dublin Core identifiers, 2) Block, describing the paraffin-embedded array of tissues, 3)Slide, describing the glass slides produced from the Block, and 4) Core, containing all data related to the individual tissue samples contained in the array. Eighty CDEs, conforming to the ISO-11179 specification for data elements constitute XML tags used in the TMA data exchange specification. A set of six simple semantic rules describe the complete data exchange specification. Anyone using the data exchange specification can validate their TMA files using a software implementation written in Perl and distributed as a supplemental file with this publication. Conclusion The TMA data exchange specification is now available in a draft form with community-approved Common Data Elements and a community-approved general file format and data structure. The specification can be freely used by the scientific community. Efforts sponsored by the Association for Pathology Informatics to refine the draft TMA data exchange specification are expected to continue for at least two more years. The interested public is invited to participate in these open efforts. Information on future workshops will be posted at (API we site). PMID:12769826

Subcellular distribution of an inhalational anesthetic in situ

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

Eckenhoff, R.G.; Shuman, H.

1990-01-01

To better understand the mechanisms and sites of anesthetic action, we determined the subcellular partitioning of halothane in a tissue model. A method was found to fix the in vivo distribution of halothane in rat atrial tissue for subsequent electron microscopy and x-ray microanalysis. Atrial strips were exposed to various concentrations of halothane, rapidly frozen, cryo-sectioned, and cryo-transferred into an electron microscope. Irradiation of the hydrated cryosections with the electron beam caused halothane radiolysis, which allowed retention of the halogen-containing fragments after dehydration of the sections. The bromine from halothane was detected and quantified with x-ray microanalysis in various microregionsmore » of atrial myocytes. Halothane (bromine) partitioned largely to mitochondria, with progressively lower concentrations in sarcolemma, nuclear membrane, cytoplasm, sarcomere, and nucleus. Partitioning could not be explained solely by distribution of cellular lipid, suggesting significant and differential physicochemical solubility in protein. However, we found no saturable compartment in atrial myocytes within the clinical concentration range, which implies little specific protein binding.« less

Polarization-Sensitive Hyperspectral Imaging in vivo: A Multimode Dermoscope for Skin Analysis

NASA Astrophysics Data System (ADS)

Vasefi, Fartash; MacKinnon, Nicholas; Saager, Rolf B.; Durkin, Anthony J.; Chave, Robert; Lindsley, Erik H.; Farkas, Daniel L.

2014-05-01

Attempts to understand the changes in the structure and physiology of human skin abnormalities by non-invasive optical imaging are aided by spectroscopic methods that quantify, at the molecular level, variations in tissue oxygenation and melanin distribution. However, current commercial and research systems to map hemoglobin and melanin do not correlate well with pathology for pigmented lesions or darker skin. We developed a multimode dermoscope that combines polarization and hyperspectral imaging with an efficient analytical model to map the distribution of specific skin bio-molecules. This corrects for the melanin-hemoglobin misestimation common to other systems, without resorting to complex and computationally intensive tissue optical models. For this system's proof of concept, human skin measurements on melanocytic nevus, vitiligo, and venous occlusion conditions were performed in volunteers. The resulting molecular distribution maps matched physiological and anatomical expectations, confirming a technologic approach that can be applied to next generation dermoscopes and having biological plausibility that is likely to appeal to dermatologists.

Measurement of drug and macromolecule diffusion across atherosclerotic rabbit aorta ex vivo by attenuated total reflection-Fourier transform infrared imaging

NASA Astrophysics Data System (ADS)

Palombo, Francesca; Danoux, Charlène B.; Weinberg, Peter D.; Kazarian, Sergei G.

2009-07-01

Diffusion of two model drugs-benzyl nicotinate and ibuprofen-and the plasma macromolecule albumin across atherosclerotic rabbit aorta was studied ex vivo by attenuated total reflection-Fourier transform infrared (ATR-FTIR) imaging. Solutions of these molecules were applied to the endothelial surface of histological sections of the aortic wall that were sandwiched between two impermeable surfaces. An array of spectra, each corresponding to a specific location in the section, was obtained at various times during solute diffusion into the wall and revealed the distribution of the solutes within the tissue. Benzyl nicotinate in Ringer's solution showed higher affinity for atherosclerotic plaque than for apparently healthy tissue. Transmural concentration profiles for albumin demonstrated its permeation across the section and were consistent with a relatively low distribution volume for the macromolecule in the middle of the wall. The ability of albumin to act as a drug carrier for ibuprofen, otherwise undetected within the tissue, was demonstrated by multivariate subtraction image analysis. In conclusion, ATR-FTIR imaging can be used to study transport processes in tissue samples with high spatial and temporal resolution and without the need to label the solutes under study.

Integrative models of vascular remodeling during tumor growth

PubMed Central

Rieger, Heiko; Welter, Michael

2015-01-01

Malignant solid tumors recruit the blood vessel network of the host tissue for nutrient supply, continuous growth, and gain of metastatic potential. Angiogenesis (the formation of new blood vessels), vessel cooption (the integration of existing blood vessels into the tumor vasculature), and vessel regression remodel the healthy vascular network into a tumor-specific vasculature that is in many respects different from the hierarchically organized arterio-venous blood vessel network of the host tissues. Integrative models based on detailed experimental data and physical laws implement in silico the complex interplay of molecular pathways, cell proliferation, migration, and death, tissue microenvironment, mechanical and hydrodynamic forces, and the fine structure of the host tissue vasculature. With the help of computer simulations high-precision information about blood flow patterns, interstitial fluid flow, drug distribution, oxygen and nutrient distribution can be obtained and a plethora of therapeutic protocols can be tested before clinical trials. In this review, we give an overview over the current status of integrative models describing tumor growth, vascular remodeling, blood and interstitial fluid flow, drug delivery, and concomitant transformations of the microenvironment. © 2015 The Authors. WIREs Systems Biology and Medicine published by Wiley Periodicals, Inc. PMID:25808551

Utilization of MAX and FAX human phantoms for space radiation exposure calculations using HZETRN

NASA Astrophysics Data System (ADS)

Qualls, Garry; Slaba, Tony; Clowdsley, Martha; Blattnig, Steve; Walker, Steven; Simonsen, Lisa

To estimate astronaut health risk due to space radiation, one must have the ability to calculate, for known radiation environments external to the body, particle spectra, LET spectra, dose, dose equivalent, or gray equivalent that are averaged over specific organs or tissue types. This may be accomplished using radiation transport software and computational human body tissue models. Historically, NASA scientists have used the HZETRN software to calculate radiation transport through both vehicle shielding materials and body tissue. The Computerized Anatomical Man (CAM) and the Computerized Anatomical Female (CAF) body models, combined with the CAMERA software, have been used for body tissue self-shielding calculations. The CAM and CAF, which were developed in 1973 and 1992, respectively, model the 50th percentile U.S. Air Force male and female and are constructed using individual quadric surfaces that combine to form thousands of solid regions that represent specific tissues and structures within the body. In order to transport an external radiation environment to a point within one of the body models using HZETRN, a directional distribution of the tissues surrounding that point is needed. The CAMERA software is used to "ray trace" the CAM and CAF models, providing the thickness of each tissue type traversed along each of a large number of rays originating at a dose point. More recently, R. Kramer of the Departmento de Energia Nuclear, Universidade Federal de Pernambuco in Brazil and his co-workers developed the Male Adult voXel (MAX) model and the Female Adult voXel (FAX). These voxel-based body models were developed using segmented Computed Tomography (CT) scans of adult cadavers, and the quantities and distributions of various body tissues have been adjusted to match those specified in the International Commission on Radiological Protection (ICRP) reference adult male and female. A new set of tools has been developed to facilitate space radiation exposure calculation using HZETRN and the MAX and FAX models. A new ray tracer was developed for these body models, as was a methodology for evaluating organ-averaged quantities. Both tools are described in this paper and utilized in sample calculations.

Development of ex vivo model for determining temperature distribution in tumor tissue during photothermal therapy

NASA Astrophysics Data System (ADS)

Liu, Shaojie; Doughty, Austin; Mesiya, Sana; Pettitt, Alex; Zhou, Feifan; Chen, Wei R.

2017-02-01

Temperature distribution in tissue is a crucial factor in determining the outcome of photothermal therapy in cancer treatment. In order to investigate the temperature distribution in tumor tissue during laser irradiation, we developed a novel ex vivo device to simulate the photothermal therapy on tumors. A 35°C, a thermostatic incubator was used to provide a simulation environment for body temperature of live animals. Different biological tissues (chicken breast and bovine liver) were buried inside a tissue-simulating gel and considered as tumor tissues. An 805-nm laser was used to irradiate the target tissue. A fiber with an interstitial cylindrical diffuser (10 mm) was directly inserted in the center of the tissue, and the needle probes of a thermocouple were inserted into the tissue paralleling the laser fiber at different distances to measure the temperature distribution. All of the procedures were performed in the incubator. Based on the results of this study, the temperature distribution in bovine liver is similar to that of tumor tissue under photothermal therapy with the same doses. Therefore, the developed model using bovine liver for determining temperature distribution can be used during interstitial photothermal therapy.

RBFOX2 protein domains and cellular activities.

PubMed

Arya, Anurada D; Wilson, David I; Baralle, Diana; Raponi, Michaela

2014-08-01

RBFOX2 (RNA-binding protein, Fox-1 homologue 2)/RBM9 (RNA-binding-motif protein 9)/RTA (repressor of tamoxifen action)/HNRBP2 (hexaribonucleotide-binding protein 2) encodes an RNA-binding protein involved in tissue specific alternative splicing regulation and steroid receptors transcriptional activity. Its ability to regulate specific splicing profiles depending on context has been related to different expression levels of the RBFOX2 protein itself and that of other splicing regulatory proteins involved in the shared modulation of specific genes splicing. However, this cannot be the sole explanation as to why RBFOX2 plays a widespread role in numerous cellular mechanisms from development to cell survival dependent on cell/tissue type. RBFOX2 isoforms with altered protein domains exist. In the present article, we describe the main RBFOX2 protein domains, their importance in the context of splicing and transcriptional regulation and we propose that RBFOX2 isoform distribution may play a fundamental role in RBFOX2-specific cellular effects.

Spatial distribution of the messenger ribonucleic acid and protein of the nuclear receptor coactivator, amplified in breast cancer-3, in mice.

PubMed

Zhang, Hao; Liao, Lan; Kuang, Shao-Qing; Xu, Jianming

2003-04-01

Transcriptional activities of nuclear receptors are modulated by coactivators and corepressors. The amplified in breast cancer-3 protein (AIB3, also known as ASC-2, RAP250, PRIP, TRBP, and NCR) is a newly identified nuclear receptor coactivator that is amplified and overexpressed in breast cancers. This study aims to investigate the spatial expression of AIB3 mRNA and protein in various murine tissues. Quantitative measurements revealed that the concentrations of AIB3 mRNA differ substantially in different tissues in a descending order from the following: testis, brain, thymus, white fat, pituitary, ovary, adrenal gland, lung, uterus, kidney, heart, skeletal muscle, liver, and virgin mammary gland. The AIB3 mRNA level in the testis is 165-fold higher than that in the virgin mammary gland. Specific antiserum was generated and used to map the distribution of AIB3 protein by immunohistochemistry. Although AIB3 protein was detected in many tissues, the AIB3 immunoreactivities varied significantly from cell type to cell type. High levels of AIB3 immunoreactivity were observed in hormone target cells including the testicular Sertoli cells, follicular granulosa cells, and epithelial cells of the prostate, uterus, mammary gland, and kidney tubules. Medium and low levels of AIB3 immunoreactivities were also detected in a variety of other cell types. These results demonstrate that AIB3 mRNA and protein are preferentially expressed in specific cell types, suggesting that AIB3 may support the function of nuclear receptors in a cell type-specific manner.

Molecular characterization, tissue distribution and feeding related changes of NUCB2A/nesfatin-1 in Ya-fish (Schizothorax prenanti).

PubMed

Lin, Fangjun; Zhou, Chaowei; Chen, Hu; Wu, Hongwei; Xin, Zhiming; Liu, Ju; Gao, Yundi; Yuan, Dengyue; Wang, Tao; Wei, Rongbin; Chen, Defang; Yang, Shiyong; Wang, Yan; Pu, Yundan; Li, Zhiqiong

2014-02-25

The protein nucleobindin-2 (NUCB2) was identified over a decade ago and recently raised great interest as its derived peptide nesfatin-1 was shown to reduce food intake and body weight in rodents. However, the involvement of NUCB2 in feeding behavior has not well been studied in fish. In the present study, we characterized the structure, distribution, and meal responsive of NUCB2A/nesfatin-1 in Ya-fish (Schizothorax prenanti) for the first time. The full length cDNA of Ya-fish was 2140base pair (bp), which encoded a polypeptide of 487 amino acid residues including a 23 amino acid signal peptide. A high conservation in NUCB2 sequences was found in vertebrates, however the proposed propeptide cleavage site (Arg-Arg) conserved among other species is not present in Ya-fish NUCB2A sequence. Tissue distribution analysis revealed that Ya-fish NUCB2A mRNA was ubiquitously expressed in all test tissues, and abundant expression was detected in several regions including the hypothalamus, hepatopancreas, ovary and intestines. NUCB2A mRNA expression respond to feeding status change may vary and be tissue specific. NUCB2A mRNA levels significantly increased (P<0.05) in the hypothalamus and intestines after feeding and substantially decreased (P<0.01) during a week food deprivation in the hypothalamus. Meanwhile, NUCB2A mRNA in the hepatopancreas was significantly elevated (P<0.001) during food deprivation, and a similar increase was also found after short-time fasting. This points toward a potential hepatopancreas specific local role for NUCB2A in the regulation of metabolism during food deprivation. Collectively, these results provide the molecular and functional evidence to support potential anorectic and metabolic roles for NUCB2A in Ya-fish. Copyright © 2013 Elsevier B.V. All rights reserved.

Evaluation of biomolecular distributions in rat brain tissues by means of ToF-SIMS using a continuous beam of Ar clusters.

PubMed

Nakano, Shusuke; Yokoyama, Yuta; Aoyagi, Satoka; Himi, Naoyuki; Fletcher, John S; Lockyer, Nicholas P; Henderson, Alex; Vickerman, John C

2016-06-08

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) provides detailed chemical structure information and high spatial resolution images. Therefore, ToF-SIMS is useful for studying biological phenomena such as ischemia. In this study, in order to evaluate cerebral microinfarction, the distribution of biomolecules generated by ischemia was measured with ToF-SIMS. ToF-SIMS data sets were analyzed by means of multivariate analysis for interpreting complex samples containing unknown information and to obtain biomolecular mapping indicated by fragment ions from the target biomolecules. Using conventional ToF-SIMS (primary ion source: Bi cluster ion), it is difficult to detect secondary ions beyond approximately 1000 u. Moreover, the intensity of secondary ions related to biomolecules is not always high enough for imaging because of low concentration even if the masses are lower than 1000 u. However, for the observation of biomolecular distributions in tissues, it is important to detect low amounts of biological molecules from a particular area of tissue. Rat brain tissue samples were measured with ToF-SIMS (J105, Ionoptika, Ltd., Chandlers Ford, UK), using a continuous beam of Ar clusters as a primary ion source. ToF-SIMS with Ar clusters efficiently detects secondary ions related to biomolecules and larger molecules. Molecules detected by ToF-SIMS were examined by analyzing ToF-SIMS data using multivariate analysis. Microspheres (45 μm diameter) were injected into the rat unilateral internal carotid artery (MS rat) to cause cerebral microinfarction. The rat brain was sliced and then measured with ToF-SIMS. The brain samples of a normal rat and the MS rat were examined to find specific secondary ions related to important biomolecules, and then the difference between them was investigated. Finally, specific secondary ions were found around vessels incorporating microspheres in the MS rat. The results suggest that important biomolecules related to cerebral microinfarction can be detected by ToF-SIMS.

Mapping the genetic and tissular diversity of 64 phenolic compounds in Citrus species using a UPLC–MS approach

PubMed Central

Durand-Hulak, Marie; Dugrand, Audray; Duval, Thibault; Bidel, Luc P. R.; Jay-Allemand, Christian; Froelicher, Yann; Bourgaud, Frédéric; Fanciullino, Anne-Laure

2015-01-01

Background and Aims Phenolic compounds contribute to food quality and have potential health benefits. Consequently, they are an important target of selection for Citrus species. Numerous studies on this subject have revealed new molecules, potential biosynthetic pathways and linkage between species. Although polyphenol profiles are correlated with gene expression, which is responsive to developmental and environmental cues, these factors are not monitored in most studies. A better understanding of the biosynthetic pathway and its regulation requires more information about environmental conditions, tissue specificity and connections between competing sub-pathways. This study proposes a rapid method, from sampling to analysis, that allows the quantitation of multiclass phenolic compounds across contrasting tissues and cultivars. Methods Leaves and fruits of 11 cultivated citrus of commercial interest were collected from adult trees grown in an experimental orchard. Sixty-four phenolic compounds were simultaneously quantified by ultra-high-performance liquid chromatography coupled with mass spectrometry. Key Results Combining data from vegetative tissues with data from fruit tissues improved cultivar classification based on polyphenols. The analysis of metabolite distribution highlighted the massive accumulation of specific phenolic compounds in leaves and the external part of the fruit pericarp, which reflects their involvement in plant defence. The overview of the biosynthetic pathway obtained confirmed some regulatory steps, for example those catalysed by rhamnosyltransferases. The results suggest that three other steps are responsible for the different metabolite profiles in ‘Clementine’ and ‘Star Ruby’ grapefruit. Conclusions The method described provides a high-throughput method to study the distribution of phenolic compounds across contrasting tissues and cultivars in Citrus, and offers the opportunity to investigate their regulation and physiological roles. The method was validated in four different tissues and allowed the identification and quantitation of 64 phenolic compounds in 20 min, which represents an improvement over existing methods of analysing multiclass polyphenols. PMID:25757470

PET Pharmacokinetic Modelling

NASA Astrophysics Data System (ADS)

Müller-Schauenburg, Wolfgang; Reimold, Matthias

Positron Emission Tomography is a well-established technique that allows imaging and quantification of tissue properties in-vivo. The goal of pharmacokinetic modelling is to estimate physiological parameters, e.g. perfusion or receptor density from the measured time course of a radiotracer. After a brief overview of clinical application of PET, we summarize the fundamentals of modelling: distribution volume, Fick's principle of local balancing, extraction and perfusion, and how to calculate equilibrium data from measurements after bolus injection. Three fundamental models are considered: (i) the 1-tissue compartment model, e.g. for regional cerebral blood flow (rCBF) with the short-lived tracer [15O]water, (ii) the 2-tissue compartment model accounting for trapping (one exponential + constant), e.g. for glucose metabolism with [18F]FDG, (iii) the reversible 2-tissue compartment model (two exponentials), e.g. for receptor binding. Arterial blood sampling is required for classical PET modelling, but can often be avoided by comparing regions with specific binding with so called reference regions with negligible specific uptake, e.g. in receptor imaging. To estimate the model parameters, non-linear least square fits are the standard. Various linearizations have been proposed for rapid parameter estimation, e.g. on a pixel-by-pixel basis, for the prize of a bias. Such linear approaches exist for all three models; e.g. the PATLAK-plot for trapping substances like FDG, and the LOGAN-plot to obtain distribution volumes for reversibly binding tracers. The description of receptor modelling is dedicated to the approaches of the subsequent lecture (chapter) of Millet, who works in the tradition of Delforge with multiple-injection investigations.

Cellular and Subcellular Immunohistochemical Localization and Quantification of Cadmium Ions in Wheat (Triticum aestivum).

PubMed

Gao, Wei; Nan, Tiegui; Tan, Guiyu; Zhao, Hongwei; Tan, Weiming; Meng, Fanyun; Li, Zhaohu; Li, Qing X; Wang, Baomin

2015-01-01

The distribution of metallic ions in plant tissues is associated with their toxicity and is important for understanding mechanisms of toxicity tolerance. A quantitative histochemical method can help advance knowledge of cellular and subcellular localization and distribution of heavy metals in plant tissues. An immunohistochemical (IHC) imaging method for cadmium ions (Cd2+) was developed for the first time for the wheat Triticum aestivum grown in Cd2+-fortified soils. Also, 1-(4-Isothiocyanobenzyl)-ethylenediamine-N,N,N,N-tetraacetic acid (ITCB-EDTA) was used to chelate the mobile Cd2+. The ITCB-EDTA/Cd2+ complex was fixed with proteins in situ via the isothiocyano group. A new Cd2+-EDTA specific monoclonal antibody, 4F3B6D9A1, was used to locate the Cd2+-EDTA protein complex. After staining, the fluorescence intensities of sections of Cd2+-positive roots were compared with those of Cd2+-negative roots under a laser confocal scanning microscope, and the location of colloidal gold particles was determined with a transmission electron microscope. The results enable quantification of the Cd2+ content in plant tissues and illustrate Cd2+ translocation and cellular and subcellular responses of T. aestivum to Cd2+ stress. Compared to the conventional metal-S coprecipitation histochemical method, this new IHC method is quantitative, more specific and has less background interference. The subcellular location of Cd2+ was also confirmed with energy-dispersive X-ray microanalysis. The IHC method is suitable for locating and quantifying Cd2+ in plant tissues and can be extended to other heavy metallic ions.

Class I and II histone deacetylase expression in human chronic periodontitis gingival tissue.

PubMed

Cantley, M D; Dharmapatni, A A S S K; Algate, K; Crotti, T N; Bartold, P M; Haynes, D R

2016-04-01

Histone deacetylase inhibitors (HDACi) are being considered to treat chronic inflammatory diseases at low doses. Currently HDACi that are more specific are being developed to target particular HDACs; therefore, this study aimed to determine levels and distribution of class I and II HDAC in human gingival samples obtained from patients with chronic periodontitis. Gingival biopsies were obtained from patients with and without (mild inflammation, no bone loss) periodontitis. Total RNA was isolated for real-time quantitative polymerase chain reaction to determine expression of HDACs 1-10. Immunohistochemistry was used to determine protein distribution of HDACs 1, 5, 8 and 9. Factor VIII, CD3 and tartrate resistant acid phosphatase (TRAP) were detected in serial sections to identify blood vessels, lymphocytes, pre-osteoclasts and osteoclasts cells respectively. Tumour necrosis factor α (TNF-α) expression was also assessed. mRNA for HDAC 1, 5, 8 and 9 were significantly upregulated in chronic periodontitis gingival tissues compared to non-periodontitis samples (p < 0.05). Significantly higher HDAC 1 protein expression was observed in chronic periodontitis samples (p < 0.05), and was associated with CD3, TRAP and TNF-α-positive cells. HDAC 1, 5, 8 and 9 were expressed strongly by the factor VIII-positive microvasculature in the chronic periodontitis gingival tissues. HDAC 1, 5, 8 and 9 expression was higher in gingival tissues from patients with chronic periodontitis compared to non-periodontitis samples. Results suggest that these HDACs could therefore be targeted with specific acting HDACi. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

High Resolution MALDI Imaging Mass Spectrometry of Retinal Tissue Lipids

NASA Astrophysics Data System (ADS)

Anderson, David M. G.; Ablonczy, Zsolt; Koutalos, Yiannis; Spraggins, Jeffrey; Crouch, Rosalie K.; Caprioli, Richard M.; Schey, Kevin L.

2014-08-01

Matrix assisted laser desorption ionization imaging mass spectrometry (MALDI IMS) has the ability to provide an enormous amount of information on the abundances and spatial distributions of molecules within biological tissues. The rapid progress in the development of this technology significantly improves our ability to analyze smaller and smaller areas and features within tissues. The mammalian eye has evolved over millions of years to become an essential asset for survival, providing important sensory input of an organism's surroundings. The highly complex sensory retina of the eye is comprised of numerous cell types organized into specific layers with varying dimensions, the thinnest of which is the 10 μm retinal pigment epithelium (RPE). This single cell layer and the photoreceptor layer contain the complex biochemical machinery required to convert photons of light into electrical signals that are transported to the brain by axons of retinal ganglion cells. Diseases of the retina, including age-related macular degeneration (AMD), retinitis pigmentosa, and diabetic retinopathy, occur when the functions of these cells are interrupted by molecular processes that are not fully understood. In this report, we demonstrate the use of high spatial resolution MALDI IMS and FT-ICR tandem mass spectrometry in the Abca4 -/- knockout mouse model of Stargardt disease, a juvenile onset form of macular degeneration. The spatial distributions and identity of lipid and retinoid metabolites are shown to be unique to specific retinal cell layers.

Comparative Transcriptomics Unravel Biochemical Specialization of Leaf Tissues of Stevia for Diterpenoid Production1

PubMed Central

Kim, Mi Jung; Jin, Jingjing; Zheng, Junshi

2015-01-01

Stevia (Stevia rebaudiana) produces not only a group of diterpenoid glycosides known as steviol glycosides (SGs), but also other labdane-type diterpenoids that may be spatially separated from SGs. However, their biosynthetic routes and spatial distribution in leaf tissues have not yet been elucidated. Here, we integrate metabolome and transcriptome analyses of Stevia to explore the biosynthetic capacity of leaf tissues for diterpenoid metabolism. Tissue-specific chemical analyses confirmed that SGs were accumulated in leaf cells but not in trichomes. On the other hand, Stevia leaf trichomes stored other labdane-type diterpenoids such as oxomanoyl oxide and agatholic acid. RNA sequencing analyses from two different tissues of Stevia provided a comprehensive overview of dynamic metabolic activities in trichomes and leaf without trichomes. These metabolite-guided transcriptomics and phylogenetic and gene expression analyses clearly identified specific gene members encoding enzymes involved in the 2-C-methyl-d-erythritol 4-phosphate pathway and the biosynthesis of steviol or other labdane-type diterpenoids. Additionally, our RNA sequencing analysis uncovered copalyl diphosphate synthase (SrCPS) and kaurene synthase1 (SrKS1) homologs, SrCPS2 and KS-like (SrKSL), which were specifically expressed in trichomes. In vitro and in planta assays showed that unlike SrCPS and SrKS1, SrCPS2 synthesized labda-13-en-8-ol diphosphate and successively catalyzed the formation of manoyl oxide and epi-manoyl oxide in combination with SrKSL. Our findings suggest that Stevia may have evolved to use distinct metabolic pathways to avoid metabolic interferences in leaf tissues for efficient production of diverse secondary metabolites. PMID:26438788

Iron biomineralization of brain tissue and neurodegenerative disorders

NASA Astrophysics Data System (ADS)

Mikhaylova (Mikhailova), Albina

The brain is an organ with a high concentration of iron in specific areas, particularly in the globus pallidus, the substantia nigra, and the red nucleus. In certain pathological states, such as iron overload disease and neurodegenerative disorders, a disturbed iron metabolism can lead to increased accumulation of iron not only in these areas, but also in the brain regions that are typically low in iron content. Recent studies of the physical and magnetic properties of metalloproteins, and in particular the discovery of biogenic magnetite in human brain tissue, have raised new questions about the role of biogenic iron formations in living organisms. Further investigations revealed the presence of magnetite-like crystalline structures in human ferritin, and indicated that released ferritin iron might act as promoter of oxidative damage to tissue, therefore contributing to pathogenesis of neurodegenerative disorders such as Alzheimer's, Parkinson's and Huntington's diseases. The purpose of this work was to examine the elemental composition and structure of iron deposits in normal brain tissue as well as tissue affected by neurodegenerative disorders. Employing the methods of X-ray microfocus fluorescence mapping, X-ray Absorption Near Edge Structure (XANES), X-ray Absorption Fine Structure spectroscopy (XAFS), and light and electron microscopic examinations allows one to obtain qualitative as well as quantitative data with respect to the cellular distribution and chemical state of iron at levels not detected previously. The described tissue preparation technique allows not only satisfactory XAS iron elemental imaging in situ but also multimodal examination with light and electron microscopes of the same samples. The developed protocol has assured consistent and reproducible results on relatively large sections of flat-embedded tissue. The resulting tissue samples were adequate for XAS examination as well as sufficiently well-preserved for future microscopy studies. The continued development of this technique should lead to major advances in mapping iron anomalies and the related chemical and structural information directly to cells and tissue structures in human brain tissue. At present this is done primarily by iron staining methods and any information on the relationship between iron distribution and cellular structures obtained this way is limited. Iron staining also offers no information on the specific compounds of iron that are present. This can be vitally important as the form of iron [including its oxidation state] in the human body can determine whether it plays a detrimental or beneficial role in neurophysiological processes.

3D Bioprinting for Organ Regeneration

PubMed Central

Cui, Haitao; Nowicki, Margaret; Fisher, John P.; Zhang, Lijie Grace

2017-01-01

Regenerative medicine holds the promise of engineering functional tissues or organs to heal or replace abnormal and necrotic tissues/organs, offering hope for filling the gap between organ shortage and transplantation needs. Three-dimensional (3D) bioprinting is evolving into an unparalleled bio-manufacturing technology due to its high-integration potential for patient-specific designs, precise and rapid manufacturing capabilities with high resolution, and unprecedented versatility. It enables precise control over multiple compositions, spatial distributions, and architectural accuracy/complexity, therefore achieving effective recapitulation of microstructure, architecture, mechanical properties, and biological functions of target tissues and organs. Here we provide an overview of recent advances in 3D bioprinting technology, as well as design concepts of bioinks suitable for the bioprinting process. We focus on the applications of this technology for engineering living organs, focusing more specifically on vasculature, neural networks, the heart and liver. We conclude with current challenges and the technical perspective for further development of 3D organ bioprinting. PMID:27995751

MURC/Cavin-4 and cavin family members form tissue-specific caveolar complexes.

PubMed

Bastiani, Michele; Liu, Libin; Hill, Michelle M; Jedrychowski, Mark P; Nixon, Susan J; Lo, Harriet P; Abankwa, Daniel; Luetterforst, Robert; Fernandez-Rojo, Manuel; Breen, Michael R; Gygi, Steven P; Vinten, Jorgen; Walser, Piers J; North, Kathryn N; Hancock, John F; Pilch, Paul F; Parton, Robert G

2009-06-29

Polymerase I and transcript release factor (PTRF)/Cavin is a cytoplasmic protein whose expression is obligatory for caveola formation. Using biochemistry and fluorescence resonance energy transfer-based approaches, we now show that a family of related proteins, PTRF/Cavin-1, serum deprivation response (SDR)/Cavin-2, SDR-related gene product that binds to C kinase (SRBC)/Cavin-3, and muscle-restricted coiled-coil protein (MURC)/Cavin-4, forms a multiprotein complex that associates with caveolae. This complex can constitutively assemble in the cytosol and associate with caveolin at plasma membrane caveolae. Cavin-1, but not other cavins, can induce caveola formation in a heterologous system and is required for the recruitment of the cavin complex to caveolae. The tissue-restricted expression of cavins suggests that caveolae may perform tissue-specific functions regulated by the composition of the cavin complex. Cavin-4 is expressed predominantly in muscle, and its distribution is perturbed in human muscle disease associated with Caveolin-3 dysfunction, identifying Cavin-4 as a novel muscle disease candidate caveolar protein.

3D Bioprinting for Organ Regeneration.

PubMed

Cui, Haitao; Nowicki, Margaret; Fisher, John P; Zhang, Lijie Grace

2017-01-01

Regenerative medicine holds the promise of engineering functional tissues or organs to heal or replace abnormal and necrotic tissues/organs, offering hope for filling the gap between organ shortage and transplantation needs. Three-dimensional (3D) bioprinting is evolving into an unparalleled biomanufacturing technology due to its high-integration potential for patient-specific designs, precise and rapid manufacturing capabilities with high resolution, and unprecedented versatility. It enables precise control over multiple compositions, spatial distributions, and architectural accuracy/complexity, therefore achieving effective recapitulation of microstructure, architecture, mechanical properties, and biological functions of target tissues and organs. Here we provide an overview of recent advances in 3D bioprinting technology, as well as design concepts of bioinks suitable for the bioprinting process. We focus on the applications of this technology for engineering living organs, focusing more specifically on vasculature, neural networks, the heart and liver. We conclude with current challenges and the technical perspective for further development of 3D organ bioprinting. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The sexually dimorphic role of adipose and adipocyte estrogen receptors in modulating adipose tissue expansion, inflammation, and fibrosis

PubMed Central

Davis, Kathryn E.; D. Neinast, Michael; Sun, Kai; M. Skiles, William; D. Bills, Jessica; A. Zehr, Jordan; Zeve, Daniel; D. Hahner, Lisa; W. Cox, Derek; M. Gent, Lana; Xu, Yong; V. Wang, Zhao; A. Khan, Sohaib; Clegg, Deborah J.

2013-01-01

Our data demonstrate that estrogens, estrogen receptor-α (ERα), and estrogen receptor-β (ERβ) regulate adipose tissue distribution, inflammation, fibrosis, and glucose homeostasis, by determining that αERKO mice have increased adipose tissue inflammation and fibrosis prior to obesity onset. Selective deletion of adipose tissue ERα in adult mice using a novel viral vector technology recapitulated the findings in the total body ERα null mice. Generation of a novel mouse model, lacking ERα specifically from adipocytes (AdipoERα), demonstrated increased markers of fibrosis and inflammation, especially in the males. Additionally, we found that the beneficial effects of estrogens on adipose tissue require adipocyte ERα. Lastly, we determined the role of ERβ in regulating inflammation and fibrosis, by breeding the AdipoERα into the βERKO background and found that in the absence of adipocyte ERα, ERβ has a protective role. These data suggest that adipose tissue and adipocyte ERα protects against adiposity, inflammation, and fibrosis in both males and females. PMID:24049737

Tissue-specific biomass recalcitrance in corn stover pretreated with liquid hot-water: enzymatic hydrolysis (part 1).

PubMed

Zeng, Meijuan; Ximenes, Eduardo; Ladisch, Michael R; Mosier, Nathan S; Vermerris, Wilfred; Huang, Chia-Ping; Sherman, Debra M

2012-02-01

Lignin content, composition, distribution as well as cell wall thickness, structures, and type of tissue have a measurable effect on enzymatic hydrolysis of cellulose in lignocellulosic feedstocks. The first part of our work combined compositional analysis, pretreatment and enzyme hydrolysis for fractionated pith, rind, and leaf tissues from a hybrid stay-green corn, in order to identify the role of structural characteristics on enzyme hydrolysis of cell walls. The extent of enzyme hydrolysis follows the sequence rind < leaves < pith with 90% conversion of cellulose to glucose in 24 h in the best cases. Physical fractionation of corn stalks or other C(4) grasses into soft and hard tissue types could reduce cost of cellulose conversion by enabling reduced enzyme loadings to hydrolyze soft tissue, and directing the hard tissue to other uses such as thermal processing, combustion, or recycle to the land from which the corn was harvested. Copyright © 2011 Wiley Periodicals, Inc.

Characterization of Aquaporin 4 Protein Expression and Localization in Tissues of the Dogfish (Squalus acanthias)

PubMed Central

Cutler, Christopher P.; Harmon, Sheena; Walsh, Jonathon; Burch, Kia

2012-01-01

The role of aquaporin water channels such as aquaporin 4 (Aqp4) in elasmobranchs such as the dogfish Squalus acanthias is completely unknown. This investigation set out to determine the expression and cellular and sub-cellular localization of Aqp4 protein in dogfish tissues. Two polyclonal antibodies were generated (AQP4/1 and AQP4/2) and these showed somewhat different characteristics in Western blotting and immunohistochemistry. Western blots using the AQP4/1 antibody showed two bands (35.5 and 49.5 kDa) in most tissues in a similar fashion to mammals. Liver had an additional band of 57 kDa and rectal gland two further faint bands of 37.5 and 38.5 kDa. However, unlike in mammals, Aqp4 protein was ubiquitously expressed in all tissues including gill and liver. The AQP4/2 antibody appeared much less specific in Western blots. Both antibodies were used in immunohistochemistry and showed similar cellular localizations, although the AQP4/2 antibody had a more restricted sub-cellular distribution compared to AQP4/1 and therefore appeared to be more specific for Aqp4. In kidney a sub-set of tubules were stained which may represent intermediate tubule segments (In-III–In-VI). AQP4/1 and AQP4/2 antibodies localized to the same tubules segments in serial sections although the intensity and sub-cellular distribution were different. AQP4/2 showed a basal or basolateral membrane distribution whereas AQP4/1 was often distributed throughout the whole cell including the nuclear region. In rectal gland and cardiac stomach Aqp4 was localized to secretory tubules but again AQP/1 and AQP/2 exhibited different sub-cellular distributions. In gill, both antibodies stained large cells in the primary filament and secondary lamellae. Again AQP4/1 antibody stained most or all the cell including the nucleus, whereas AQP4/2 had a plasma membrane or plasma membrane and cytoplasmic distribution. Two types of large mitochondrial rich transport cells are known to exist in elasmobranchs, that express either Na, K-ATPase, or V-type ATPase ion transporters. Using Na, K-ATPase, and V-type ATPase antibodies, Aqp4 was colocalized with these proteins using the AQP4/1 antibody. Results show Aqp4 is expressed in both (and all) branchial Na, K-ATPase, and V-type ATPase expressing cells. PMID:22363294

Characterization of Aquaporin 4 Protein Expression and Localization in Tissues of the Dogfish (Squalus acanthias).

PubMed

Cutler, Christopher P; Harmon, Sheena; Walsh, Jonathon; Burch, Kia

2012-01-01

The role of aquaporin water channels such as aquaporin 4 (Aqp4) in elasmobranchs such as the dogfish Squalus acanthias is completely unknown. This investigation set out to determine the expression and cellular and sub-cellular localization of Aqp4 protein in dogfish tissues. Two polyclonal antibodies were generated (AQP4/1 and AQP4/2) and these showed somewhat different characteristics in Western blotting and immunohistochemistry. Western blots using the AQP4/1 antibody showed two bands (35.5 and 49.5 kDa) in most tissues in a similar fashion to mammals. Liver had an additional band of 57 kDa and rectal gland two further faint bands of 37.5 and 38.5 kDa. However, unlike in mammals, Aqp4 protein was ubiquitously expressed in all tissues including gill and liver. The AQP4/2 antibody appeared much less specific in Western blots. Both antibodies were used in immunohistochemistry and showed similar cellular localizations, although the AQP4/2 antibody had a more restricted sub-cellular distribution compared to AQP4/1 and therefore appeared to be more specific for Aqp4. In kidney a sub-set of tubules were stained which may represent intermediate tubule segments (In-III-In-VI). AQP4/1 and AQP4/2 antibodies localized to the same tubules segments in serial sections although the intensity and sub-cellular distribution were different. AQP4/2 showed a basal or basolateral membrane distribution whereas AQP4/1 was often distributed throughout the whole cell including the nuclear region. In rectal gland and cardiac stomach Aqp4 was localized to secretory tubules but again AQP/1 and AQP/2 exhibited different sub-cellular distributions. In gill, both antibodies stained large cells in the primary filament and secondary lamellae. Again AQP4/1 antibody stained most or all the cell including the nucleus, whereas AQP4/2 had a plasma membrane or plasma membrane and cytoplasmic distribution. Two types of large mitochondrial rich transport cells are known to exist in elasmobranchs, that express either Na, K-ATPase, or V-type ATPase ion transporters. Using Na, K-ATPase, and V-type ATPase antibodies, Aqp4 was colocalized with these proteins using the AQP4/1 antibody. Results show Aqp4 is expressed in both (and all) branchial Na, K-ATPase, and V-type ATPase expressing cells.

Possible roles of mechanical cell elimination intrinsic to growing tissues from the perspective of tissue growth efficiency and homeostasis.

PubMed

Lee, Sang-Woo; Morishita, Yoshihiro

2017-07-01

Cell competition is a phenomenon originally described as the competition between cell populations with different genetic backgrounds; losing cells with lower fitness are eliminated. With the progress in identification of related molecules, some reports described the relevance of cell mechanics during elimination. Furthermore, recent live imaging studies have shown that even in tissues composed of genetically identical cells, a non-negligible number of cells are eliminated during growth. Thus, mechanical cell elimination (MCE) as a consequence of mechanical cellular interactions is an unavoidable event in growing tissues and a commonly observed phenomenon. Here, we studied MCE in a genetically-homogeneous tissue from the perspective of tissue growth efficiency and homeostasis. First, we propose two quantitative measures, cell and tissue fitness, to evaluate cellular competitiveness and tissue growth efficiency, respectively. By mechanical tissue simulation in a pure population where all cells have the same mechanical traits, we clarified the dependence of cell elimination rate or cell fitness on different mechanical/growth parameters. In particular, we found that geometrical (specifically, cell size) and mechanical (stress magnitude) heterogeneities are common determinants of the elimination rate. Based on these results, we propose possible mechanical feedback mechanisms that could improve tissue growth efficiency and density/stress homeostasis. Moreover, when cells with different mechanical traits are mixed (e.g., in the presence of phenotypic variation), we show that MCE could drive a drastic shift in cell trait distribution, thereby improving tissue growth efficiency through the selection of cellular traits, i.e. intra-tissue "evolution". Along with the improvement of growth efficiency, cell density, stress state, and phenotype (mechanical traits) were also shown to be homogenized through growth. More theoretically, we propose a mathematical model that approximates cell competition dynamics, by which the time evolution of tissue fitness and cellular trait distribution can be predicted without directly simulating a cell-based mechanical model.

Possible roles of mechanical cell elimination intrinsic to growing tissues from the perspective of tissue growth efficiency and homeostasis

PubMed Central

2017-01-01

Cell competition is a phenomenon originally described as the competition between cell populations with different genetic backgrounds; losing cells with lower fitness are eliminated. With the progress in identification of related molecules, some reports described the relevance of cell mechanics during elimination. Furthermore, recent live imaging studies have shown that even in tissues composed of genetically identical cells, a non-negligible number of cells are eliminated during growth. Thus, mechanical cell elimination (MCE) as a consequence of mechanical cellular interactions is an unavoidable event in growing tissues and a commonly observed phenomenon. Here, we studied MCE in a genetically-homogeneous tissue from the perspective of tissue growth efficiency and homeostasis. First, we propose two quantitative measures, cell and tissue fitness, to evaluate cellular competitiveness and tissue growth efficiency, respectively. By mechanical tissue simulation in a pure population where all cells have the same mechanical traits, we clarified the dependence of cell elimination rate or cell fitness on different mechanical/growth parameters. In particular, we found that geometrical (specifically, cell size) and mechanical (stress magnitude) heterogeneities are common determinants of the elimination rate. Based on these results, we propose possible mechanical feedback mechanisms that could improve tissue growth efficiency and density/stress homeostasis. Moreover, when cells with different mechanical traits are mixed (e.g., in the presence of phenotypic variation), we show that MCE could drive a drastic shift in cell trait distribution, thereby improving tissue growth efficiency through the selection of cellular traits, i.e. intra-tissue “evolution”. Along with the improvement of growth efficiency, cell density, stress state, and phenotype (mechanical traits) were also shown to be homogenized through growth. More theoretically, we propose a mathematical model that approximates cell competition dynamics, by which the time evolution of tissue fitness and cellular trait distribution can be predicted without directly simulating a cell-based mechanical model. PMID:28704373

A Novel Approach to High-Quality Postmortem Tissue Procurement: The GTEx Project.

PubMed

Carithers, Latarsha J; Ardlie, Kristin; Barcus, Mary; Branton, Philip A; Britton, Angela; Buia, Stephen A; Compton, Carolyn C; DeLuca, David S; Peter-Demchok, Joanne; Gelfand, Ellen T; Guan, Ping; Korzeniewski, Greg E; Lockhart, Nicole C; Rabiner, Chana A; Rao, Abhi K; Robinson, Karna L; Roche, Nancy V; Sawyer, Sherilyn J; Segrè, Ayellet V; Shive, Charles E; Smith, Anna M; Sobin, Leslie H; Undale, Anita H; Valentino, Kimberly M; Vaught, Jim; Young, Taylor R; Moore, Helen M

2015-10-01

The Genotype-Tissue Expression (GTEx) project, sponsored by the NIH Common Fund, was established to study the correlation between human genetic variation and tissue-specific gene expression in non-diseased individuals. A significant challenge was the collection of high-quality biospecimens for extensive genomic analyses. Here we describe how a successful infrastructure for biospecimen procurement was developed and implemented by multiple research partners to support the prospective collection, annotation, and distribution of blood, tissues, and cell lines for the GTEx project. Other research projects can follow this model and form beneficial partnerships with rapid autopsy and organ procurement organizations to collect high quality biospecimens and associated clinical data for genomic studies. Biospecimens, clinical and genomic data, and Standard Operating Procedures guiding biospecimen collection for the GTEx project are available to the research community.

The relationship between maternal body composition in early pregnancy and foetal mid-thigh soft-tissue thickness in the third trimester in a high-risk obstetric population.

PubMed

Anglim, Breffini; Farah, Nadine; O'Connor, Clare; Daly, Niamh; Kennelly, Mairead M; Turner, Michael J

2017-07-01

Maternal obesity is an emerging challenge in contemporary obstetrics. To date there has been no study analysing the relationship between specific maternal body composition measurements and foetal soft-tissue measurements. The aim of this study was to determine whether measurement of maternal body composition at booking predicts foetal soft-tissue trajectories in the third trimester. We analysed the relationship between foetal thigh in the third trimester and both maternal BMI and body composition using the Tanita digital scales in the first trimester. Foetal subcutaneous thigh tissue measurements were obtained at intervals of 28, 32 and 36 weeks of gestation. A total of 160 women were identified. There was a direct correlation between MTST at 36 weeks and BMI (p = .002). There was a positive correlation between MTST at 36 weeks and leg fat mass (p = .13) and leg fat free mass (p = .013). There was a positive correlation between arm fat free mass and MTST at 36 weeks. We showed there is an association between maternal fat distribution and foetal subcutaneous thigh tissue measurements. MTST may be more useful in determining if a child is at risk of macrosomia. Impact statement Previous studies have suggested that maternal obesity programmes intrauterine foetal adiposity and growth. The aim of this study was to examine the relationship in a high-risk obstetric population between measurements of maternal body composition in early pregnancy and the assessment of foetal adiposity in the third trimester using serial ultrasound measurements of mid-thigh soft-tissue thickness. BMI is only a surrogate measurement of fat and does not measure fat distribution. Our study shows the distribution of both maternal fat and fat-free mass in early pregnancy may be positively associated with foetal soft-tissue measurements in the third trimester. Maternal arthropometric measurements other than BMI may help predict babies at risk of macrosomia and neonatal adiposity.

Tracking of multimodal therapeutic nanocomplexes targeting breast cancer in vivo.

PubMed

Bardhan, Rizia; Chen, Wenxue; Bartels, Marc; Perez-Torres, Carlos; Botero, Maria F; McAninch, Robin Ward; Contreras, Alejandro; Schiff, Rachel; Pautler, Robia G; Halas, Naomi J; Joshi, Amit

2010-12-08

Nanoparticle-based therapeutics with local delivery and external electromagnetic field modulation holds extraordinary promise for soft-tissue cancers such as breast cancer; however, knowledge of the distribution and fate of nanoparticles in vivo is crucial for clinical translation. Here we demonstrate that multiple diagnostic capabilities can be introduced in photothermal therapeutic nanocomplexes by simultaneously enhancing both near-infrared fluorescence and magnetic resonance imaging (MRI). We track nanocomplexes in vivo, examining the influence of HER2 antibody targeting on nanocomplex distribution over 72 h. This approach provides valuable, detailed information regarding the distribution and fate of complex nanoparticles designed for specific diagnostic and therapeutic functions.

Tracking of Multimodal Therapeutic Nanocomplexes Targeting Breast Cancer in Vivo

PubMed Central

Bardhan, Rizia; Chen, Wenxue; Bartels, Marc; Perez-Torres, Carlos; Botero, Maria F.; McAninch, Robin Ward; Contreras, Alejandro; Schiff, Rachel; Pautler, Robia G.; Halas, Naomi J.; Joshi, Amit

2014-01-01

Nanoparticle-based therapeutics with local delivery and external electromagnetic field modulation holds extraordinary promise for soft-tissue cancers such as breast cancer; however, knowledge of the distribution and fate of nanoparticles in vivo is crucial for clinical translation. Here we demonstrate that multiple diagnostic capabilities can be introduced in photothermal therapeutic nanocomplexes by simultaneously enhancing both near-infrared fluorescence and magnetic resonance imaging (MRI). We track nanocomplexes in vivo, examining the influence of HER2 antibody targeting on nanocomplex distribution over 72 h. This approach provides valuable, detailed information regarding the distribution and fate of complex nanoparticles designed for specific diagnostic and therapeutic functions. PMID:21090693

Therapy of Ovarian Carcinoma by Targeted Delivery of Alpha-Particles Using Immunoliposomes Capable of Retaining Alpha-Emitting Daughters

DTIC Science & Technology

2005-10-01

Trastuzumab- antibody conjugated to 225Ac. The radioactivity distribution is represented as the tissue-to- kidney activity concentration ratio, since...generally low specific activity (0.038 mCi/mg in this study) that corresponds to one conjugated 225Ac atom per 2,300 antibodies . With the current...antigens (35). Radiolabeled antibodies with 225Ac have generally low specific activity (0.038 mCi/mg in this study) that corresponds to one conjugated

Macrophage Biochemistry, Activation and Function

DTIC Science & Technology

1981-01-01

vacuolar apparatus become more abundant. Functional capabilities, including phagocytic activity, protein synthesis and surface receptors, also increase...properties of cell components of other tissues has led to the following assignment of marker enzymes to specific macrophage components. This assessment is...subfractions. The surface area of each histogram bar then gives the frac- tional amount of constituent present within each normalized fraction. Distribution

Mechanobiological simulations of peri-acetabular bone ingrowth: a comparative analysis of cell-phenotype specific and phenomenological algorithms.

PubMed

Mukherjee, Kaushik; Gupta, Sanjay

2017-03-01

Several mechanobiology algorithms have been employed to simulate bone ingrowth around porous coated implants. However, there is a scarcity of quantitative comparison between the efficacies of commonly used mechanoregulatory algorithms. The objectives of this study are: (1) to predict peri-acetabular bone ingrowth using cell-phenotype specific algorithm and to compare these predictions with those obtained using phenomenological algorithm and (2) to investigate the influences of cellular parameters on bone ingrowth. The variation in host bone material property and interfacial micromotion of the implanted pelvis were mapped onto the microscale model of implant-bone interface. An overall variation of 17-88 % in peri-acetabular bone ingrowth was observed. Despite differences in predicted tissue differentiation patterns during the initial period, both the algorithms predicted similar spatial distribution of neo-tissue layer, after attainment of equilibrium. Results indicated that phenomenological algorithm, being computationally faster than the cell-phenotype specific algorithm, might be used to predict peri-prosthetic bone ingrowth. The cell-phenotype specific algorithm, however, was found to be useful in numerically investigating the influence of alterations in cellular activities on bone ingrowth, owing to biologically related factors. Amongst the host of cellular activities, matrix production rate of bone tissue was found to have predominant influence on peri-acetabular bone ingrowth.

Estimation of the minimum permeability coefficient in rats for perfusion-limited tissue distribution in whole-body physiologically-based pharmacokinetics.

PubMed

Jeong, Yoo-Seong; Yim, Chang-Soon; Ryu, Heon-Min; Noh, Chi-Kyoung; Song, Yoo-Kyung; Chung, Suk-Jae

2017-06-01

The objective of the current study was to determine the minimum permeability coefficient, P, needed for perfusion-limited distribution in PBPK. Two expanded kinetic models, containing both permeability and perfusion terms for the rate of tissue distribution, were considered: The resulting equations could be simplified to perfusion-limited distribution depending on tissue permeability. Integration plot analyses were carried out with theophylline in 11 typical tissues to determine their apparent distributional clearances and the model-dependent permeabilities of the tissues. Effective surface areas were calculated for 11 tissues from the tissue permeabilities of theophylline and its PAMPA P. Tissue permeabilities of other drugs were then estimated from their PAMPA P and the effective surface area of the tissues. The differences between the observed and predicted concentrations, as expressed by the sum of squared log differences with the present models were at least comparable to or less than the values obtained using the traditional perfusion-limited distribution model for 24 compounds with diverse PAMPA P values. These observations suggest that the use of a combination of the proposed models, PAMPA P and the effective surface area can be used to reasonably predict the pharmacokinetics of 22 out of 24 model compounds, and is potentially applicable to calculating the kinetics for other drugs. Assuming that the fractional distribution parameter of 80% of the perfusion rate is a reasonable threshold for perfusion-limited distribution in PBPK, our theoretical prediction indicates that the pharmacokinetics of drugs having an apparent PAMPA P of 1×10 -6 cm/s or more will follow the traditional perfusion-limited distribution in PBPK for major tissues in the body. Copyright © 2017 Elsevier B.V. All rights reserved.

Effects of surface displayed targeting ligand GE11 on liposome distribution and extravasation in tumor.

PubMed

Tang, Hailing; Chen, Xiaojing; Rui, Mengjie; Sun, Wenqiang; Chen, Jian; Peng, Jinliang; Xu, Yuhong

2014-10-06

Targeting ligands displayed on liposome surface had been used to mediate specific interactions and drug delivery to target cells. However, they also affect liposome distribution in vivo, as well as the tissue extravasation processes after IV injection. In this study, we incorporated an EGFR targeting peptide GE11 on liposome surfaces in addition to PEG at different densities and evaluated their targeting properties and antitumor effects. We found that the densities of surface ligand and PEG were critical to target cell binding in vitro as well as pharmacokinetic profiles in vivo. The inclusion of GE11-PEG-DSPE and PEG-DSPE at 2% and 4% mol ratios in the liposome formulation mediated a rapid accumulation of liposomes within 1 h after IV injection in the tumor tissues surrounding neovascular structures. This is in addition to the EPR effect that was most prominently described for surface PEG modified liposomes. Therefore, despite the fact that the distribution of liposomes into interior tumor tissues was still limited by diffusion, GE11 targeted doxorubicin loaded liposomes showed significantly better antitumor activity in tumor bearing mice as a result of the fast active-targeting efficiency. We anticipate these understandings can benefit further optimization of targeted drug delivery systems for improving efficacy in vivo.

Numerical simulation of the plantar pressure distribution in the diabetic foot during the push-off stance.

PubMed

Actis, Ricardo L; Ventura, Liliana B; Smith, Kirk E; Commean, Paul K; Lott, Donovan J; Pilgram, Thomas K; Mueller, Michael J

2006-08-01

The primary objective of conservative care for the diabetic foot is to protect the foot from excessive pressures. Pressure reduction and redistribution may be achieved by designing and fabricating orthotic devices based on foot structure, tissue mechanics, and external loads on the diabetic foot. The purpose of this paper is to describe the process used for the development of patient-specific mathematical models of the second and third rays of the foot, their solution by the finite element method, and their sensitivity to model parameters and assumptions. We hypothesized that the least complex model to capture the pressure distribution in the region of the metatarsal heads would include the bony structure segmented as toe, metatarsal and support, with cartilage between the bones, plantar fascia and soft tissue. To check the hypothesis, several models were constructed with different levels of details. The process of numerical simulation is comprised of three constituent parts: model definition, numerical solution and prediction. In this paper the main considerations relating model selection and computation of approximate solutions by the finite element method are considered. The fit of forefoot plantar pressures estimated using the FEA models and those explicitly tested were good as evidenced by high Pearson correlations (r=0.70-0.98) and small bias and dispersion. We concluded that incorporating bone support, metatarsal and toes with linear material properties, tendon and fascia with linear material properties, soft tissue with nonlinear material properties, is sufficient for the determination of the pressure distribution in the metatarsal head region in the push-off position, both barefoot and with shoe and total contact insert. Patient-specific examples are presented.

Sensitivity of reentrant driver localization to electrophysiological parameter variability in image-based computational models of persistent atrial fibrillation sustained by a fibrotic substrate

NASA Astrophysics Data System (ADS)

Deng, Dongdong; Murphy, Michael J.; Hakim, Joe B.; Franceschi, William H.; Zahid, Sohail; Pashakhanloo, Farhad; Trayanova, Natalia A.; Boyle, Patrick M.

2017-09-01

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, causing morbidity and mortality in millions worldwide. The atria of patients with persistent AF (PsAF) are characterized by the presence of extensive and distributed atrial fibrosis, which facilitates the formation of persistent reentrant drivers (RDs, i.e., spiral waves), which promote fibrillatory activity. Targeted catheter ablation of RD-harboring tissues has shown promise as a clinical treatment for PsAF, but the outcomes remain sub-par. Personalized computational modeling has been proposed as a means of non-invasively predicting optimal ablation targets in individual PsAF patients, but it remains unclear how RD localization dynamics are influenced by inter-patient variability in the spatial distribution of atrial fibrosis, action potential duration (APD), and conduction velocity (CV). Here, we conduct simulations in computational models of fibrotic atria derived from the clinical imaging of PsAF patients to characterize the sensitivity of RD locations to these three factors. We show that RDs consistently anchor to boundaries between fibrotic and non-fibrotic tissues, as delineated by late gadolinium-enhanced magnetic resonance imaging, but those changes in APD/CV can enhance or attenuate the likelihood that an RD will anchor to a specific site. These findings show that the level of uncertainty present in patient-specific atrial models reconstructed without any invasive measurements (i.e., incorporating each individual's unique distribution of fibrotic tissue from medical imaging alongside an average representation of AF-remodeled electrophysiology) is sufficiently high that a personalized ablation strategy based on targeting simulation-predicted RD trajectories alone may not produce the desired result.

Numerical simulation studies for optical properties of biomaterials

NASA Astrophysics Data System (ADS)

Krasnikov, I.; Seteikin, A.

2016-11-01

Biophotonics involves understanding how light interacts with biological matter, from molecules and cells, to tissues and even whole organisms. Light can be used to probe biomolecular events, such as gene expression and protein-protein interaction, with impressively high sensitivity and specificity. The spatial and temporal distribution of biochemical constituents can also be visualized with light and, thus, the corresponding physiological dynamics in living cells, tissues, and organisms in real time. Computer-based Monte Carlo (MC) models of light transport in turbid media take a different approach. In this paper, the optical and structural properties of biomaterials discussed. We explain the numerical simulationmethod used for studying the optical properties of biomaterials. Applications of the Monte-Carlo method in photodynamic therapy, skin tissue optics, and bioimaging described.

The distribution of glutathione and homoglutathione in leaf, root and seed tissue of 73 species across the three sub-families of the Leguminosae.

PubMed

Colville, Louise; Sáez, Clara M Blanco; Lewis, Gwilym P; Kranner, Ilse

2015-07-01

Homoglutathione (γ-glutamyl-cysteinyl-β-alanine) is a homologue of glutathione (γ-glutamyl-cysteinyl-glycine), which is a ubiquitous and indispensable tripeptide in eukaryotes with multi-facetted functions, many of which relate to cellular redox regulation. Homoglutathione is unique to the Leguminosae family, but studies of its occurrence have been restricted to the Papilionoideae subfamily, and almost exclusively to crop species. To determine whether the distribution of homoglutathione in the Leguminosae has a phylogenetic basis the occurrence of homoglutathione was investigated in the leaves, roots and seeds of 73 wild species of Leguminosae, representing 30 tribes across the Caesalpinioideae, Mimosoideae and Papilionoideae subfamilies. Homoglutathione was found only in the Papilionoideae, and was generally restricted to the 'Old World Clade'. It is proposed that homoglutathione may have arisen following a whole genome duplication event after the divergence of the Old World Clade. Homoglutathione is believed to fulfil the same functional roles as glutathione, but this study showed that homoglutathione and glutathione have different tissue-specific distribution patterns. Homoglutathione tended to occur more frequently in root tissue, and higher concentrations were found in leaves and roots, whereas glutathione tended to be present at the highest concentrations in seeds. This may reflect a distinct role for homoglutathione, particularly in roots, or an inability of homoglutathione to functionally replace glutathione in reproductive tissues. However, no relationships with environmental factors or nodulation were observed. Greater understanding of the factors that influence homoglutathione distribution may help to elucidate its unique function in some legume species. Copyright © 2015 Elsevier Ltd. All rights reserved.

Transport of Gold Nanoparticles by Vascular Endothelium from Different Human Tissues

PubMed Central

Gromnicova, Radka; Kaya, Mehmet; Romero, Ignacio A.; Williams, Phil; Satchell, Simon; Sharrack, Basil; Male, David

2016-01-01

The selective entry of nanoparticles into target tissues is the key factor which determines their tissue distribution. Entry is primarily controlled by microvascular endothelial cells, which have tissue-specific properties. This study investigated the cellular properties involved in selective transport of gold nanoparticles (<5 nm) coated with PEG-amine/galactose in two different human vascular endothelia. Kidney endothelium (ciGENC) showed higher uptake of these nanoparticles than brain endothelium (hCMEC/D3), reflecting their biodistribution in vivo. Nanoparticle uptake and subcellular localisation was quantified by transmission electron microscopy. The rate of internalisation was approximately 4x higher in kidney endothelium than brain endothelium. Vesicular endocytosis was approximately 4x greater than cytosolic uptake in both cell types, and endocytosis was blocked by metabolic inhibition, whereas cytosolic uptake was energy-independent. The cellular basis for the different rates of internalisation was investigated. Morphologically, both endothelia had similar profiles of vesicles and cell volumes. However, the rate of endocytosis was higher in kidney endothelium. Moreover, the glycocalyces of the endothelia differed, as determined by lectin-binding, and partial removal of the glycocalyx reduced nanoparticle uptake by kidney endothelium, but not brain endothelium. This study identifies tissue-specific properties of vascular endothelium that affects their interaction with nanoparticles and rate of transport. PMID:27560685

Placenta-specific drug delivery by trophoblast-targeted nanoparticles in mice

PubMed Central

Zhang, Baozhen; Tan, Lunbo; Yu, Yan; Wang, Baobei; Chen, Zhilong; Han, Jinyu; Li, Mengxia; Chen, Jie; Xiao, Tianxia; Ambati, Balamurali K; Cai, Lintao; Yang, Qing; Nayak, Nihar R; Zhang, Jian; Fan, Xiujun

2018-01-01

Rationale: The availability of therapeutics to treat pregnancy complications is severely lacking, mainly due to the risk of harm to the fetus. In placental malaria, Plasmodium falciparum-infected erythrocytes (IEs) accumulate in the placenta by adhering to chondroitin sulfate A (CSA) on the surfaces of trophoblasts. Based on this principle, we have developed a method for targeted delivery of payloads to the placenta using a synthetic placental CSA-binding peptide (plCSA-BP) derived from VAR2CSA, a CSA-binding protein expressed on IEs. Methods: A biotinylated plCSA-BP was used to examine the specificity of plCSA-BP binding to mouse and human placental tissue in tissue sections in vitro. Different nanoparticles, including plCSA-BP-conjugated nanoparticles loaded with indocyanine green (plCSA-INPs) or methotrexate (plCSA-MNPs), were administered intravenously to pregnant mice to test their efficiency at drug delivery to the placenta in vivo. The tissue distribution and localization of the plCSA-INPs were monitored in live animals using an IVIS imaging system. The effect of plCSA-MNPs on fetal and placental development and pregnancy outcome were examined using a small-animal high-frequency ultrasound (HFUS) imaging system, and the concentrations of methotrexate in fetal and placental tissues were measured using high-performance liquid chromatography (HPLC). Results: plCSA-BP binds specifically to trophoblasts and not to other cell types in the placenta or to CSA-expressing cells in other tissues. Moreover, we found that intravenously administered plCSA-INPs accumulate in the mouse placenta, and ex vivo analysis of the fetuses and placentas confirmed placenta-specific delivery of these nanoparticles. We also demonstrate successful delivery of methotrexate specifically to placental cells by plCSA-BP-conjugated nanoparticles, resulting in dramatic impairment of placental and fetal development. Importantly, plCSA-MNPs treatment had no apparent adverse effects on maternal tissues. Conclusion: These results demonstrate that plCSA-BP-guided nanoparticles could be used for the targeted delivery of payloads to the placenta and serve as a novel placenta-specific drug delivery option. PMID:29774074

Overall Adiposity, Adipose Tissue Distribution, and Endometriosis: A Systematic Review.

PubMed

Backonja, Uba; Buck Louis, Germaine M; Lauver, Diane R

2016-01-01

Endometriosis has been associated with a lean body habitus. However, we do not understand whether endometriosis is also associated with other characteristics of adiposity, including adipose tissue distribution and amount of visceral adipose tissue (VAT; adipose tissue lining inner organs). Having these understandings may provide insights on how endometriosis develops-some of the physiological actions of adipose tissue differ depending on tissue amount and location and are related to proposed mechanisms of endometriosis development. The aim of this study was to review the literature regarding overall adiposity, adipose tissue distribution and/or VAT, and endometriosis. We reviewed and synthesized studies indexed in PubMed and/or Web of Science. We included studies that had one or more measures of overall adiposity, adipose tissue distribution, and/or VAT and women with and without endometriosis for comparison. We summarized the findings and commented on the methods used and potential sources of bias. Of 366 identified publications, 19 (5.2%) were eligible. Two additional publications were identified from reference lists. Current research included measures of overall adiposity (e.g., body figure drawings) or adipose tissue distribution (e.g., waist-to-hip ratio), but not VAT. The weight of evidence indicated that endometriosis was associated with low overall adiposity and with a preponderance of adipose tissue distributed below the waist (peripheral). Endometriosis may be associated with being lean or having peripherally distributed adipose tissue. Well-designed studies with various sampling frameworks and precise measures of adiposity and endometriosis are needed to confirm associations between adiposity measures and endometriosis and delineate potential etiological mechanisms underlying endometriosis.

Comparative plasma and tissue distribution of Sun Pharma's generic doxorubicin HCl liposome injection versus Caelyx® (doxorubicin HCl liposome injection) in syngeneic fibrosarcoma-bearing BALB/c mice and Sprague-Dawley rats.

PubMed

Burade, Vinod; Bhowmick, Subhas; Maiti, Kuntal; Zalawadia, Rishit; Jain, Deepak; Rajamannar, Thennati

2017-05-01

The liposomal formulation of doxorubicin [doxorubicin (DXR) hydrochloride (HCl) liposome injection, Caelyx ® ] alters the tissue distribution of DXR as compared with nonliposomal DXR, resulting in an improved benefit-risk profile. We conducted studies in murine models to compare the plasma and tissue distribution of a proposed generic DXR HCl liposome injection developed by Sun Pharmaceuticals Industries Limited (SPIL DXR HCl liposome injection) with Caelyx ® . The plasma and tissue distributions of the SPIL and reference DXR HCl liposome injections were compared in syngeneic fibrosarcoma-bearing BALB/c mice and Sprague-Dawley rats. Different batches and different lots of the same batch of the reference product were also compared with each other. The SPIL and reference DXR HCl liposome injections exhibited generally comparable plasma and tissue distribution profiles in both models. While minor differences were observed between the two products in some tissues, different batches and lots of the reference product also showed some differences in the distribution of various analytes in some tissues. The ratios of estimated free to encapsulated DXR for plasma and tissue were generally comparable between the SPIL and reference DXR HCl liposome injections in both models, indicating similar extents of absorption into the tissues and similar rates of drug release from liposomes. The plasma and tissue distribution profiles of the SPIL and reference DXR HCl liposome injections were shown to be generally comparable. Inconsistencies between the products observed in some tissues were thought to be due to biological variation.

Overall Adiposity, Adipose Tissue Distribution, and Endometriosis: A Systematic Review

PubMed Central

Backonja, Uba; Buck Louis, Germaine M.; Lauver, Diane R.

2015-01-01

Background Endometriosis has been associated with a lean body habitus. However, we do not understand whether endometriosis is also associated with other characteristics of adiposity, including adipose tissue distribution and amount of visceral adipose tissue (VAT; adipose tissue lining inner organs). Having these understandings may provide insights on how endometriosis develops—some of the physiologic actions of adipose tissue differ depending on tissue amount and location, and are related to proposed mechanisms of endometriosis development. Objectives To review the literature regarding overall adiposity, adipose tissue distribution and/or VAT, and endometriosis. Methods We reviewed and synthesized studies indexed in PubMed and/or Web of Science. We included studies that had one or more measures of overall adiposity, adipose tissue distribution, and/or VAT, and women with and without endometriosis for comparison. We summarized the findings and commented on the methods used and potential sources of bias. Results Out of 366 identified publications, 19 (5.2%) were eligible. Two additional publications were identified from reference lists. Current research included measures of overall adiposity (e.g., body figure drawings) or adipose tissue distribution (e.g., waist-to-hip ratio), but not VAT. The weight of evidence indicated that endometriosis was associated with low overall adiposity and with a preponderance of adipose tissue distributed below the waist (peripheral). Discussion Endometriosis may be associated with being lean or having peripherally distributed adipose tissue. Well-designed studies with various sampling frameworks and precise measures of adiposity and endometriosis are needed to confirm associations between adiposity measures and endometriosis, and delineate potential etiologic mechanisms underlying endometriosis. PMID:26938364

Detection of Gastric Cancer with Novel Methylated DNA Markers: Discovery, Tissue Validation, and Pilot Testing in Plasma.

PubMed

Anderson, Bradley W; Suh, Yun-Suhk; Choi, Boram; Lee, Hyuk-Joon; Yab, Tracy C; Taylor, William; Dukek, Brian A; Berger, Calise K; Cao, Xiaoming; Foote, Patrick H; Devens, Mary E; Boardman, Lisa A; Kisiel, John B; Mahoney, Douglas W; Slettedahl, Seth W; Allawi, Hatim T; Lidgard, Graham P; Smyrk, Thomas C; Yang, Han-Kwang; Ahlquist, David A

2018-05-29

Gastric adenocarcinoma (GAC) is the third most common cause of cancer mortality worldwide. Accurate and affordable non-invasive detection methods have potential value for screening and surveillance. Herein, we identify novel methylated DNA markers (MDMs) for GAC, validate their discrimination for GAC in tissues from geographically separate cohorts, explore marker acquisition through the oncogenic cascade, and describe distributions of candidate MDMs in plasma from GAC cases and normal controls. Following discovery by unbiased whole methylome sequencing, candidate MDMs were validated by blinded methylation-specific PCR in archival case-control tissues from U.S. and South Korean patients. Top MDMs were then assayed by an analytically sensitive method (quantitative real-time allele-specific target and signal amplification) in a blinded pilot study on archival plasma from GAC cases and normal controls. Whole methylome discovery yielded novel and highly discriminant candidate MDMs. In tissue, a panel of candidate MDMs detected GAC in 92-100% of U.S. and S. Korean cohorts at 100% specificity. Levels of most MDMs increased progressively from normal mucosa through metaplasia, adenoma, and GAC with variation in points of greatest marker acquisition. In plasma, a 3 marker panel ( ELMO1 , ZNF569 , C13orf18) detected 86% (95% CI 71-95%) of GACs at 95% specificity. Novel MDMs appear to accurately discriminate GAC from normal controls in both tissue and plasma. The point of aberrant methylation during oncogenesis varies by MDM, which may have relevance to marker selection in clinical applications. Further exploration of these MDMs for GAC screening and surveillance is warranted. Copyright ©2018, American Association for Cancer Research.

Full-length Transcriptome Sequencing and Modular Organization Analysis of Naringin/Neoeriocitrin Related Gene Expression Pattern in Drynaria roosii.

PubMed

Sun, Mei-Yu; Li, Jing-Yi; Li, Dong; Huang, Feng-Jie; Wang, Di; Li, Hui; Xing, Quan; Zhu, Hui-Bin; Shi, Lei

2018-04-12

Drynaria roosii (Nakaike) is a traditional Chinese medicinal fern, known as 'GuSuiBu'. The corresponding effective components of naringin/neoeriocitrin share highly similar chemical structure and medicinal function. Our HPLC-MS/MS results showed that the accumulation of naringin/neoeriocitrin depended on specific tissues or ages. However, little was known about the expression patterns of naringin/neoeriocitrin related genes involved in their regulatory pathways. For lack of the basic genetic information, we applied a combination of SMRT sequencing and SGS to generate the complete and full-length transcriptome of D. roosii. According to the SGS data, the DEG-based heat map analysis revealed the naringin/neoeriocitrin related gene expression exhibited obvious tissue- and time-specific transcriptomic differences. Using the systems biology method of modular organization analysis, we clustered 16,472 DEGs into 17 gene modules and studied the relationships between modules and tissue/time point samples, as well as modules and naringin/neoeriocitrin contents. Hereinto, naringin/neoeriocitrin related DEGs distributed in nine distinct modules, and DEGs in these modules showed significant different patterns of transcript abundance to be linked with specific tissues or ages. Moreover, WGCNA results further identified that PAL, 4CL, C4H and C3H, HCT acted as the major hub genes involved in naringin and neoeriocitrin synthesis respectively and exhibited high co-expression with MYB- and bHLH-regulated genes. In this work, modular organization and co-expression networks elucidated the tissue- and time-specificity of gene expression pattern, as well as hub genes associated with naringin/neoeriocitrin synthesis in D. roosii. Simultaneously, the comprehensive transcriptome dataset provided the important genetic information for further research on D. roosii.

Microdialysis as a way to measure antibiotics concentration in tissues.

PubMed

Marchand, Sandrine; Chauzy, Alexia; Dahyot-Fizelier, Claire; Couet, William

2016-09-01

As for all other drugs, antibiotics must reach their pharmacodynamic target in order to exert their effect, but because infection may occur in various tissues the distribution of antibiotics has always been of particular concern. In this article, we will first critically review the various methodologies available to study antibiotics tissue distribution, including microdialysis, secondly we will show how basic pharmacokinetic concepts may help to predict or interpret antibiotics tissue distribution and third we will address the question of linking antibiotics tissue distribution with their antimicrobial effect, using modern pharmacokinetic-pharmacodynamic methods. Copyright © 2016 Elsevier Ltd. All rights reserved.

Immunohistochemistry for the MEPHISTO X-PEEM

NASA Astrophysics Data System (ADS)

Gilbert, B.; Neumann, M.; Steen, S.; Gabel, D.; Andres, R.; Perfetti, P.; Margaritondo, G.; De Stasio, Gelsomina

2000-05-01

Over almost 50 years of its development, the science of immunology has become an indispensable tool for the understanding of the histology of tissues. Antibodies are highly specific probes, so that tissue structure can be interpreted not just by morphological considerations but by association with a wide variety of physiological molecular antigens. The simple concept of an antibody linked to a microscopically dense marker remains constant in each application of the technique, such as the use of fluorescent markers or the incorporation of electron-dense gold colloids for electron microscopy. We describe a new application of immunocytochemistry to x-ray spectromicroscopy: the antibody labeling of tissue structures with nickel precipitates. Regions of positive staining can be seen by the acquisition of nickel distribution maps in the MEPHISTO X-PEEM from the intense Ni L-edge absorption features around 850 eV. The aim of this work is to know the background tissue structures on which the distribution of other relevant elements (such as boron for BNCT) can be mapped. Results are presented showing positive staining by two antibodies in human glioblastoma tissue, anti-Ki-67, a protein found in the nuclei of proliferating cells, and anti-van Willebrandt factor, located in blood vessel endothelia. We show that the criteria for successful staining for optical microscopy are different than for spectroscopic imaging, but useful results can be obtained with careful image treatment.

Amelioration of sexual behavior and motor activity deficits in a castrated rodent model with a selective androgen receptor modulator SARM-2f

PubMed Central

Morimoto, Megumi; Amano, Yuichiro; Oka, Masahiro; Harada, Ayako; Fujita, Hisashi; Hikichi, Yukiko; Tozawa, Ryuichi; Yamaoka, Masuo

2017-01-01

Sarcopenia and cachexia present characteristic features of a decrease in skeletal muscle mass and strength, anorexia, and lack of motivation. Treatments for these diseases have not yet been established, although selective androgen receptor modulators (SARMs) are considered as therapeutic targets. We previously reported that a novel SARM compound, SARM-2f, exhibits anabolic effect on muscles, with less stimulatory effect on prostate weight compared with testosterone, in rat Hershberger assays and cancer cachexia models. In this study, we studied the mechanism of action for SARM-2f selectivity and also assessed whether the muscle increase by this compound might lead to improvement of muscle function and physical activity. First, we examined the tissue distribution of SARM-2f. Tissue concentration was 1.2-, 1.6-, and 1.9-fold as high as the plasma concentration in the levator ani muscle, brain, and prostate, respectively. This result showed that the tissue-selective pharmacological effect did not depend on SARM-2f concentration in the tissues. The ability of SARM-2f to influence androgen receptor (AR)-mediated transcriptional activation was examined by reporter assays using human normal prostate epithelial cells (PrEC) and skeletal muscle cells (SKMC). SARM-2f exerted higher activity against AR in SKMC than in PrEC. Mammalian two hybrid assays showed different co-factor recruitment patterns between SARM-2f and dihydrotestosterone. Next, we studied the effect of SARM-2f on motivation and physical functions such as sexual behavior and motor activities in castrated rat or mouse models. SARM-2f restored the sexual behavior that was lost by castration in male rats. SARM-2f also increased voluntary running distance and locomotor activities. These results suggest that tissue-specific AR regulation by SARM-2f, but not tissue distribution, might account for its tissue specific androgenic effect, and that the muscle mass increase by SARM-2f leads to improvement of physical function. Together, these findings suggest that SARM-2f might represent an effective treatment for sarcopenia and cachexia. PMID:29216311

Bioaccumulation of six PCB indicator congeners in a heavily polluted water reservoir in Eastern Slovakia: tissue-specific distribution in fish and their parasites.

PubMed

Brázová, Tímea; Hanzelová, Vladimíra; Miklisová, Dana

2012-08-01

Concentrations of six indicator PCB congeners (IUPAC nos. 28, 52, 101, 138, 153, and 180) were measured in several organs and adipose tissue of a freshwater predatory fishes (European perch, northern pike, pike perch, wels catfish) as well as in nonpredators (common carp, freshwater bream, goldfish, white bream) and in acanthocephalan Acanthocephalus lucii from the water reservoir Zemplínska šírava (Eastern Slovakia), which is considered to be one of the most PCB-contaminated places in Europe. Concentration of PCBs was determined by capillary gas chromatography in samples from May to September 2009. The two-way main-effect ANOVA confirmed that feeding habits of fish (P < 0.00001) and peculiarity of individual fish organs (P < 0.01) affect PCB bioaccumulation. The total amount of PCBs was significantly higher (P < 0.05) in predators compared to nonpredators. Tissue-specific differences were found in PCB accumulation in both fish groups. PCBs were predominantly accumulated in the liver and hard roe. Individual congeners were not distributed homogeneously within the investigated organs and adipose tissue. PCB 153 was present in higher concentrations than the other congeners in all fish organs as well as in adipose tissue comprising an average 31 and 34 % of ΣPCB in predators and nonpredators, respectively. Acanthocephalans, attached to the intestine of perch, absorbed significantly higher concentrations of PCBs (P < 0.001) than the muscles, liver, kidney, brain, and adipose tissue of their host. About 20 times lower amount of PCBs was detected in the liver and almost 3 times in muscles of infected perch. Data on PCB accumulation in perch infected with acanthocephalans demonstrated a decline of PCB values in all organs as well as in adipose tissue compared to noninfected fish. About 20 times lower amount of PCBs was detected in the liver and almost 3 times in muscles of infected perch. Present results could indicate that some parasitic organisms may influence positively their hosts in PCB-contaminated environment.

The model of drugs distribution dynamics in biological tissue

NASA Astrophysics Data System (ADS)

Ginevskij, D. A.; Izhevskij, P. V.; Sheino, I. N.

2017-09-01

The dose distribution by Neutron Capture Therapy follows the distribution of 10B in the tissue. The modern models of pharmacokinetics of drugs describe the processes occurring in conditioned "chambers" (blood-organ-tumor), but fail to describe the spatial distribution of the drug in the tumor and in normal tissue. The mathematical model of the spatial distribution dynamics of drugs in the tissue, depending on the concentration of the drug in the blood, was developed. The modeling method is the representation of the biological structure in the form of a randomly inhomogeneous medium in which the 10B distribution occurs. The parameters of the model, which cannot be determined rigorously in the experiment, are taken as the quantities subject to the laws of the unconnected random processes. The estimates of 10B distribution preparations in the tumor and healthy tissue, inside/outside the cells, are obtained.

Ornithine decarboxylase activity in rat organs and tissues under artificial hypobiosis.

PubMed

Aksyonova, G E; Logvinovich, O S; Fialkovskaya, L A; Afanasyev, V N; Ignat'ev, D A; Kolomiytseva, I K

2010-09-01

The influence of hypothermia-hypoxia-hypercapnia on ornithine decarboxylase (ODC, EC 4.1.1.17) activities in rat organs and tissues and also on the thymocyte distribution throughout the cell cycle stages was studied. The state of artificial hypobiosis in rats on decrease in the body temperature to 14.4-18.0°C during 3.0-3.5 h was accompanied by drops in the ODC activities in the neocortex and liver by 50-60% and in rapidly proliferating tissues (thymus, spleen, and small intestine mucosa) by 80% of the control value. In kidneys the ODC activity raised to 200% of the control level. Twenty-four hours after termination of the cooling and replacing the rats under the standard conditions, the ODC activities in the neocortex, liver, kidneys, spleen, and intestinal mucosa returned to the control values, but remained decreased in the thymus. Forty-eight hours later the ODC activities in the thymus and spleen exceeded the normal level. The distribution of thymocytes throughout the cell cycle stages did not change in rats in the state of hypothermia (hypobiosis); 24 and 48 h after termination of the cooling the fraction of thymocytes in the S stage was decreased and the fraction of the cells in the G(0)+G(1) stage was increased. The normal distribution of thymocytes throughout the cell cycle stages recovered in 72 h. Thus, in the thymus the diminution of the ODC activity preceded the suppression of the cell proliferation rate. The tissue-specific changes in the ODC activity are suggested to reflect adaptive changes in the functional and proliferative activities of organs and tissues during the development of hypobiosis under conditions of hypothermia-hypoxia-hypercapnia.

Overdenture retaining bar stress distribution: a finite-element analysis.

PubMed

Caetano, Conrado Reinoldes; Mesquita, Marcelo Ferraz; Consani, Rafael Leonardo Xediek; Correr-Sobrinho, Lourenço; Dos Santos, Mateus Bertolini Fernandes

2015-05-01

Evaluate the stress distribution on the peri-implant bone tissue and prosthetic components of bar-clip retaining systems for overdentures presenting different implant inclinations, vertical misfit and framework material. Three-dimensional models of a jaw and an overdenture retained by two implants and a bar-clip attachment were modeled using specific software (SolidWorks 2010). The studied variables were: latero-lateral inclination of one implant (-10°, -5°, 0°, +5°, +10°); vertical misfit on the other implant (50, 100, 200 µm); and framework material (Au type IV, Ag-Pd, Ti cp, Co-Cr). Solid models were imported into mechanical simulation software (ANSYS Workbench 11). All nodes on the bone's external surface were constrained and a displacement was applied to simulate the settling of the framework on the ill-fitted component. Von Mises stress for the prosthetic components and maximum principal stress to the bone tissue were evaluated. The +10° inclination presented the worst biomechanical behavior, promoting the highest stress values on the bar framework and peri-implant bone tissue. The -5° group presented the lowest stress values on the prosthetic components and the lowest stress value on peri-implant bone tissue was observed in -10°. Increased vertical misfit caused an increase on the stress values in all evaluated structures. Stiffer framework materials caused a considerable stress increase in the framework itself, prosthetic screw of the fitted component and peri-implant bone tissue. Inclination of one implant associated with vertical misfit caused a relevant effect on the stress distribution in bar-clip retained overdentures. Different framework materials promoted increased levels of stress in all the evaluated structures.

A Comprehensive Specimen-Specific Multiscale Data Set for Anatomical and Mechanical Characterization of the Tibiofemoral Joint

PubMed Central

Chokhandre, Snehal; Colbrunn, Robb; Bennetts, Craig; Erdemir, Ahmet

2015-01-01

Understanding of tibiofemoral joint mechanics at multiple spatial scales is essential for developing effective preventive measures and treatments for both pathology and injury management. Currently, there is a distinct lack of specimen-specific biomechanical data at multiple spatial scales, e.g., joint, tissue, and cell scales. Comprehensive multiscale data may improve the understanding of the relationship between biomechanical and anatomical markers across various scales. Furthermore, specimen-specific multiscale data for the tibiofemoral joint may assist development and validation of specimen-specific computational models that may be useful for more thorough analyses of the biomechanical behavior of the joint. This study describes an aggregation of procedures for acquisition of multiscale anatomical and biomechanical data for the tibiofemoral joint. Magnetic resonance imaging was used to acquire anatomical morphology at the joint scale. A robotic testing system was used to quantify joint level biomechanical response under various loading scenarios. Tissue level material properties were obtained from the same specimen for the femoral and tibial articular cartilage, medial and lateral menisci, anterior and posterior cruciate ligaments, and medial and lateral collateral ligaments. Histology data were also obtained for all tissue types to measure specimen-specific cell scale information, e.g., cellular distribution. This study is the first of its kind to establish a comprehensive multiscale data set for a musculoskeletal joint and the presented data collection approach can be used as a general template to guide acquisition of specimen-specific comprehensive multiscale data for musculoskeletal joints. PMID:26381404

Detection of viral infection and gene expression in clinical tissue specimens using branched DNA (bDNA) in situ hybridization.

PubMed

Kenny, Daryn; Shen, Lu-Ping; Kolberg, Janice A

2002-09-01

In situ hybridization (ISH) methods for detection of nucleic acid sequences have proved especially powerful for revealing genetic markers and gene expression in a morphological context. Although target and signal amplification technologies have enabled researchers to detect relatively low-abundance molecules in cell extracts, the sensitive detection of nucleic acid sequences in tissue specimens has proved more challenging. We recently reported the development of a branched DNA (bDNA) ISH method for detection of DNA and mRNA in whole cells. Based on bDNA signal amplification technology, bDNA ISH is highly sensitive and can detect one or two copies of DNA per cell. In this study we evaluated bDNA ISH for detection of nucleic acid sequences in tissue specimens. Using normal and human papillomavirus (HPV)-infected cervical biopsy specimens, we explored the cell type-specific distribution of HPV DNA and mRNA by bDNA ISH. We found that bDNA ISH allowed rapid, sensitive detection of nucleic acids with high specificity while preserving tissue morphology. As an adjunct to conventional histopathology, bDNA ISH may improve diagnostic accuracy and prognosis for viral and neoplastic diseases.

A study of cryogenic tissue-engineered liver slices in calcium alginate gel for drug testing.

PubMed

Chen, Ruomeng; Wang, Bo; Liu, Yaxiong; Lin, Rong; He, Jiankang; Li, Dichen

2018-06-01

To address issues such as transportation and the time-consuming nature of tissue-engineered liver for use as an effective drug metabolism and toxicity testing model, "ready-to-use" cryogenic tissue-engineered liver needs to be studied. The research developed a cryogenic tissue-engineered liver slice (TELS), which comprised of HepG2 cells and calcium alginate gel. Cell viability and liver-specific functions were examined after different cryopreservation and recovery culture times. Then, cryogenic TELSs were used as a drug-testing model and treated with Gefitinib. Cryogenic TELSs were stored at -80 °C to ensure high cell viability. During recovery in culture, the cells in the cryogenic TELS were evenly distributed, massively proliferated, and then formed spheroid-like aggregates from day 1 to day 13. The liver-specific functions in the cryogenic TELS were closely related to cryopreservation time and cell proliferation. As a reproducible drug-testing model, the cryogenic TELS showed an obvious drug reaction after treatment with the Gefitinib. The present study shows that the cryopreservation techniques can be used in drug-testing models. Copyright © 2018 Elsevier Inc. All rights reserved.

Detection and localization of specific antigens in the reproductive tracts of cycling, pregnant, and ovariectomized hamsters.

PubMed

Fox, L L; Shivers, C A

1975-06-01

A systematic search was made for components specific to the female reproductive tract in golden hamsters. Antisera produced in rabbits against saline homogenates of hamster uteri (collected on the night of estrus) cross-reacted extensively with extracts of 12 other tissues in agar gel double-diffusion assays. Absorption of the antisera with small intestine, lung, and liver rendered the immune sera specific for uterine and oviductal antigens (within the limits of the sensitivity of the precipitin assays). Immunoelectrophoretic analysis resolved 12 uterine antigens, many of which were similar to components in several other tissues. Absorbed antisera specific for reproductive tract antigens formed one postalbumin arc with uterine and oviductal extracts in immunoelectrophoretic studies. No reactions were detected between specific antisera and five other organ extracts or plasma. An indirect immunofluorescent antibody technique was used to detect changes in the distribution of specific antigens in reproductive tracts of cycling, pregnant, and ovariectomized hamsters. The gamma-globulin fraction of anti-uterus sera (absorbed with small intestine, lung, and liver), shown to be specific for reproductive tract tissues in precipitin tests, was used to localize antigens. Appropriate controls indicated that the fluorescence observed was due to antigen-antibody interactions. During the cycle, specific antigens were usually confined to the ampullary lamina propria, except during estrus, when they were prominent in the lamina propria and luminal epithelium of the ampula. Specific antigens were never abundant in the isthmus of nonpregnant hamsters. On day 1 postcoitum, the components were found throughout the ampullary and isthmic regions. By day 2 postcoitum, ampullary antigens were usually confined to the lamina propria. The specific components were not prominent in the oviduct on day 3 postcoitum, but were conspicuous in both ampulla and isthmus on day 4. Specific antigens in the uterus were confined to endometrial glands in nonpregnant animals during proestrus, estrus, and (occasionally) metestrus. Diestrous uteri contained no specific antigens. During the first 2 days of pregnancy, antigens were not abundant and were usually confined to the glands and stroma. On days 3 and 4 of pregnancy the specific antigens were prominent in the endometrial glands and stroma and along the apical borders of some luminal epithelial cells. By day 5, these components were less conspicuous in all areas of the endometrium. Uteri of spayed animals receiving no hormones or estradiol alone lacked the specific antigens. However, progesterone (after estrogen priming) promoted the appearance of these components, and the distribution resembled that seen in uteri of 3- and 4-day pregnant animals.

Clinical features and epidemiology of cryptococcosis in cats and dogs in California: 93 cases (1988-2010).

PubMed

Trivedi, Sameer R; Sykes, Jane E; Cannon, Matthew S; Wisner, Erik R; Meyer, Wieland; Sturges, Beverly K; Dickinson, Peter J; Johnson, Lynelle R

2011-08-01

To compare clinical features of cryptococcosis among cats and dogs in California, determine whether the distribution of involved tissues differs from distribution reported previously in a study in southeastern Australia, and identify Cryptococcus spp isolated from the study population. Retrospective case series. 62 cats and 31 dogs with cryptococcosis. Medical records of cats and dogs with cryptococcosis were reviewed. Information collected included geographic location, species, signalment, and tissues or organs involved. Cryptococcosis was confirmed via serology, cytology, histology, or microbial culture, and molecular typing was performed. Odds ratios and 95% confidence intervals were calculated to determine significant associations among variables. Other comparisons were evaluated via χ(2) or unpaired t tests. American Cocker Spaniels were overrepresented, compared with other dog breeds. Serum cryptococcal antigen test results were positive in 51 of 53 cats and 15 of 18 dogs tested. Cryptococcus gattii was more commonly detected in cats (7/9 for which species identification was performed), and Cryptococcus neoformans was more commonly detected in dogs (6/8). Six of 7 C gattii isolates from cats were molecular type VGIII. Distribution of involved tissues was different between cats and dogs in California and between populations of the present study and those of the previously reported Australian study. Strains of Cryptococcus spp appeared to have host specificity in dogs and cats. Differences in lesion distribution between geographic locations may reflect strain differences or referral bias. Antigen assays alone may not be sufficient for diagnosis of cryptococcosis in cats and dogs.

Accumulation and distribution of selenium in mussel and shrimp tissues

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

Fowler, S.W.; Benayoun, G.

1976-09-01

The tissue distribution of selenium in mussels and shrimp was examined and the bioaccumulation kinetics in the various tissues was elucidated with the aid of radio selenium. Mussels (Mytilus galloprovincialis) and shrimp (Lysmata seticaudata) collected near the Monaco port, were apportioned into several groups. One group of mussels and shrimp was maintained in sea water containing 0.8 ..mu..Ci/liter high specific activity Se-75. Three to four individuals were dissected and their tissues monitored for Se-75 content periodically. Another group of shrimp, maintained in flowing sea water, were fed ad libitum mussels that had previously accumulated Se-75 from sea water for severalmore » days. Shrimp were periodically dissected to follow tissue accumulation of ingested selenium. The highest concentrations of selenium were found in the exoskeleton, presumably due, in part, to the relatively large amount of isotope sorbed to its outer surface. Molts, cast by shrimp at various times throughout uptake, contained from 60 to 90% of the total Se-75 body burden. Direct uptake of water led to initially small fractions in internal tissues such as muscle and viscera compared to the relatively large fraction associated with the exoskeleton. With time percentages in internal tissues gradually increased relative to that in the exoskeleton. When Se-75 was accumulated through the food chain an opposite trend was noted with the Se-75 fraction in exoskeleton slowly increasing and that in viscera decreasing during the course of the experiment. All tissues examined readily accumulated the isotope and, in general, did not appear to have reached a steady state concentration after 63 days. The highest Se-75 concentrations were found in the visceral mass with lesser amounts in gills, muscle and mantle, in that order.« less

Distributed effects of biological sex define sex-typical motor behavior in Caenorhabditis elegans.

PubMed

Mowrey, William R; Bennett, Jessica R; Portman, Douglas S

2014-01-29

Sex differences in shared behaviors (for example, locomotion and feeding) are a nearly universal feature of animal biology. Though these behaviors may share underlying neural programs, their kinematics can exhibit robust differences between males and females. The neural underpinnings of these differences are poorly understood because of the often-untested assumption that they are determined by sex-specific body morphology. Here, we address this issue in the nematode Caenorhabditis elegans, which features two sexes with distinct body morphologies but similar locomotor circuitry and body muscle. Quantitative behavioral analysis shows that C. elegans and related nematodes exhibit significant sex differences in the dynamics and geometry of locomotor body waves, such that the male is generally faster. Using a recently proposed model of locomotor wave propagation, we show that sex differences in both body mechanics and the intrinsic dynamics of the motor system can contribute to kinematic differences in distinct mechanical contexts. By genetically sex-reversing the properties of specific tissues and cells, however, we find that sex-specific locomotor frequency in C. elegans is determined primarily by the functional modification of shared sensory neurons. Further, we find that sexual modification of body wall muscle together with the nervous system is required to alter body wave speed. Thus, rather than relying on a single focus of modification, sex differences in motor dynamics require independent modifications to multiple tissue types. Our results suggest shared motor behaviors may be sex-specifically optimized though distributed modifications to several aspects of morphology and physiology.

Distributed Effects of Biological Sex Define Sex-Typical Motor Behavior in Caenorhabditis elegans

PubMed Central

Mowrey, William R.; Bennett, Jessica R.

2014-01-01

Sex differences in shared behaviors (for example, locomotion and feeding) are a nearly universal feature of animal biology. Though these behaviors may share underlying neural programs, their kinematics can exhibit robust differences between males and females. The neural underpinnings of these differences are poorly understood because of the often-untested assumption that they are determined by sex-specific body morphology. Here, we address this issue in the nematode Caenorhabditis elegans, which features two sexes with distinct body morphologies but similar locomotor circuitry and body muscle. Quantitative behavioral analysis shows that C. elegans and related nematodes exhibit significant sex differences in the dynamics and geometry of locomotor body waves, such that the male is generally faster. Using a recently proposed model of locomotor wave propagation, we show that sex differences in both body mechanics and the intrinsic dynamics of the motor system can contribute to kinematic differences in distinct mechanical contexts. By genetically sex-reversing the properties of specific tissues and cells, however, we find that sex-specific locomotor frequency in C. elegans is determined primarily by the functional modification of shared sensory neurons. Further, we find that sexual modification of body wall muscle together with the nervous system is required to alter body wave speed. Thus, rather than relying on a single focus of modification, sex differences in motor dynamics require independent modifications to multiple tissue types. Our results suggest shared motor behaviors may be sex-specifically optimized though distributed modifications to several aspects of morphology and physiology. PMID:24478342

The role of Monosaccharide Transport Proteins in carbohydrate assimilation, distribution, metabolism and homeostasis

PubMed Central

Cura, Anthony J.; Carruthers, Anthony

2012-01-01

The facilitated diffusion of glucose, galactose, fructose, urate, myoinositol and dehydroascorbic acid in mammals is catalyzed by a family of 14 monosaccharide transport proteins called GLUTs. These transporters may be divided into 3 classes according to sequence similarity and function/substrate specificity. GLUT1 appears to be highly expressed in glycolytically active cells and has been co-opted in vitamin C auxotrophs to maintain the redox state of the blood through transport of dehydroascorbate. Several GLUTs are definitive glucose/galactose transporters, GLUT2 and GLUT5 are physiologically important fructose transporters, GLUT9 appears to be a urate transporter while GLUT13 (HMIT1) is a proton/myoinositol co-transporter. The physiologic substrates of some GLUTs remain to be established. The GLUTs are expressed in a tissue specific manner where affinity, specificity and capacity for substrate transport are paramount for tissue function. Although great strides have been made in characterizing GLUT-catalyzed monosaccharide transport and mapping GLUT membrane topography and determinants of substrate specificity, a unifying model for GLUT structure and function remains elusive. The GLUTs play a major role in carbohydrate homeostasis and the redistribution of sugar-derived carbons among the various organ systems. This is accomplished through a multiplicity of GLUT-dependent glucose sensing and effector mechanisms that regulate monosaccharide ingestion, absorption, distribution, cellular transport and metabolism and recovery/retention. Glucose transport and metabolism have co-evolved in mammals to support cerebral glucose utilization. PMID:22943001

Three-Dimensional Radiobiologic Dosimetry: Application of Radiobiologic Modeling to Patient-Specific 3-Dimensional Imaging–Based Internal Dosimetry

PubMed Central

Prideaux, Andrew R.; Song, Hong; Hobbs, Robert F.; He, Bin; Frey, Eric C.; Ladenson, Paul W.; Wahl, Richard L.; Sgouros, George

2010-01-01

Phantom-based and patient-specific imaging-based dosimetry methodologies have traditionally yielded mean organ-absorbed doses or spatial dose distributions over tumors and normal organs. In this work, radiobiologic modeling is introduced to convert the spatial distribution of absorbed dose into biologically effective dose and equivalent uniform dose parameters. The methodology is illustrated using data from a thyroid cancer patient treated with radioiodine. Methods Three registered SPECT/CT scans were used to generate 3-dimensional images of radionuclide kinetics (clearance rate) and cumulated activity. The cumulated activity image and corresponding CT scan were provided as input into an EGSnrc-based Monte Carlo calculation: The cumulated activity image was used to define the distribution of decays, and an attenuation image derived from CT was used to define the corresponding spatial tissue density and composition distribution. The rate images were used to convert the spatial absorbed dose distribution to a biologically effective dose distribution, which was then used to estimate a single equivalent uniform dose for segmented volumes of interest. Equivalent uniform dose was also calculated from the absorbed dose distribution directly. Results We validate the method using simple models; compare the dose-volume histogram with a previously analyzed clinical case; and give the mean absorbed dose, mean biologically effective dose, and equivalent uniform dose for an illustrative case of a pediatric thyroid cancer patient with diffuse lung metastases. The mean absorbed dose, mean biologically effective dose, and equivalent uniform dose for the tumor were 57.7, 58.5, and 25.0 Gy, respectively. Corresponding values for normal lung tissue were 9.5, 9.8, and 8.3 Gy, respectively. Conclusion The analysis demonstrates the impact of radiobiologic modeling on response prediction. The 57% reduction in the equivalent dose value for the tumor reflects a high level of dose nonuniformity in the tumor and a corresponding reduced likelihood of achieving a tumor response. Such analyses are expected to be useful in treatment planning for radionuclide therapy. PMID:17504874

Primary and secondary particle contributions to the depth dose distribution in a phantom shielded from solar flare and Van Allen protons

NASA Technical Reports Server (NTRS)

Santoro, R. T.; Claiborne, H. C.; Alsmiller, R. G., Jr.

1972-01-01

Calculations have been made using the nucleon-meson transport code NMTC to estimate the absorbed dose and dose equivalent distributions in astronauts inside space vehicles bombarded by solar flare and Van Allen protons. A spherical shell shield of specific radius and thickness with a 30-cm-diam. tissue ball at the geometric center was used to simulate the spacecraft-astronaut configuration. The absorbed dose and the dose equivalent from primary protons, secondary protons, heavy nuclei, charged pions, muons, photons, and positrons and electrons are given as a function of depth in the tissue phantom. Results are given for solar flare protons with a characteristic rigidity of 100 MV and for Van Allen protons in a 240-nautical-mile circular orbit at 30 degree inclination angle incident on both 20-g/sq cm-thick aluminum and polyethylene spherical shell shields.

The inclusion of capillary distribution in the adiabatic tissue homogeneity model of blood flow

NASA Astrophysics Data System (ADS)

Koh, T. S.; Zeman, V.; Darko, J.; Lee, T.-Y.; Milosevic, M. F.; Haider, M.; Warde, P.; Yeung, I. W. T.

2001-05-01

We have developed a non-invasive imaging tracer kinetic model for blood flow which takes into account the distribution of capillaries in tissue. Each individual capillary is assumed to follow the adiabatic tissue homogeneity model. The main strength of our new model is in its ability to quantify the functional distribution of capillaries by the standard deviation in the time taken by blood to pass through the tissue. We have applied our model to the human prostate and have tested two different types of distribution functions. Both distribution functions yielded very similar predictions for the various model parameters, and in particular for the standard deviation in transit time. Our motivation for developing this model is the fact that the capillary distribution in cancerous tissue is drastically different from in normal tissue. We believe that there is great potential for our model to be used as a prognostic tool in cancer treatment. For example, an accurate knowledge of the distribution in transit times might result in an accurate estimate of the degree of tumour hypoxia, which is crucial to the success of radiation therapy.

TU-F-18C-05: Evaluation of a Method to Calculate Patient-Oriented MGD Coefficients Using Estimates of Glandular Tissue Distribution

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

Porras-Chaverri, M; University of Costa Rica, San Jose; Galavis, P

Purpose: Evaluate mammographic mean glandular dose (MGD) coefficients for particular known tissue distributions using a novel formalism that incorporates the effect of the heterogeneous glandular tissue distribution, by comparing them with MGD coefficients derived from the corresponding anthropomorphic computer breast phantom. Methods: MGD coefficients were obtained using MCNP5 simulations with the currently used homogeneous assumption and the heterogeneously-layered breast (HLB) geometry and compared against those from the computer phantom (ground truth). The tissue distribution for the HLB geometry was estimated using glandularity map image pairs corrected for the presence of non-glandular fibrous tissue. Heterogeneity of tissue distribution was quantified usingmore » the glandular tissue distribution index, Idist. The phantom had 5 cm compressed breast thickness (MLO and CC views) and 29% whole breast glandular percentage. Results: Differences as high as 116% were found between the MGD coefficients with the homogeneous breast core assumption and those from the corresponding ground truth. Higher differences were found for cases with more heterogeneous distribution of glandular tissue. The Idist for all cases was in the [−0.8{sup −}+0.3] range. The use of the methods presented in this work results in better agreement with ground truth with an improvement as high as 105 pp. The decrease in difference across all phantom cases was in the [9{sup −}105] pp range, dependent on the distribution of glandular tissue and was larger for the cases with the highest Idist values. Conclusion: Our results suggest that the use of corrected glandularity image pairs, as well as the HLB geometry, improves the estimates of MGD conversion coefficients by accounting for the distribution of glandular tissue within the breast. The accuracy of this approach with respect to ground truth is highly dependent on the particular glandular tissue distribution studied. Predrag Bakic discloses current funding from NIH, NSF, and DoD, former funding from Real Time Tomography, LLC and a current research collaboration with Barco and Hologic.« less

Comparative Transcriptomics Unravel Biochemical Specialization of Leaf Tissues of Stevia for Diterpenoid Production.

PubMed

Kim, Mi Jung; Jin, Jingjing; Zheng, Junshi; Wong, Limsoon; Chua, Nam-Hai; Jang, In-Cheol

2015-12-01

Stevia (Stevia rebaudiana) produces not only a group of diterpenoid glycosides known as steviol glycosides (SGs), but also other labdane-type diterpenoids that may be spatially separated from SGs. However, their biosynthetic routes and spatial distribution in leaf tissues have not yet been elucidated. Here, we integrate metabolome and transcriptome analyses of Stevia to explore the biosynthetic capacity of leaf tissues for diterpenoid metabolism. Tissue-specific chemical analyses confirmed that SGs were accumulated in leaf cells but not in trichomes. On the other hand, Stevia leaf trichomes stored other labdane-type diterpenoids such as oxomanoyl oxide and agatholic acid. RNA sequencing analyses from two different tissues of Stevia provided a comprehensive overview of dynamic metabolic activities in trichomes and leaf without trichomes. These metabolite-guided transcriptomics and phylogenetic and gene expression analyses clearly identified specific gene members encoding enzymes involved in the 2-C-methyl-d-erythritol 4-phosphate pathway and the biosynthesis of steviol or other labdane-type diterpenoids. Additionally, our RNA sequencing analysis uncovered copalyl diphosphate synthase (SrCPS) and kaurene synthase1 (SrKS1) homologs, SrCPS2 and KS-like (SrKSL), which were specifically expressed in trichomes. In vitro and in planta assays showed that unlike SrCPS and SrKS1, SrCPS2 synthesized labda-13-en-8-ol diphosphate and successively catalyzed the formation of manoyl oxide and epi-manoyl oxide in combination with SrKSL. Our findings suggest that Stevia may have evolved to use distinct metabolic pathways to avoid metabolic interferences in leaf tissues for efficient production of diverse secondary metabolites. © 2015 American Society of Plant Biologists. All Rights Reserved.

An integrated approach to identify normal tissue expression of targets for antibody-drug conjugates: case study of TENB2

PubMed Central

Boswell, C Andrew; Mundo, Eduardo E; Firestein, Ron; Zhang, Crystal; Mao, Weiguang; Gill, Herman; Young, Cynthia; Ljumanovic, Nina; Stainton, Shannon; Ulufatu, Sheila; Fourie, Aimee; Kozak, Katherine R; Fuji, Reina; Polakis, Paul; Khawli, Leslie A; Lin, Kedan

2013-01-01

Background and Purpose The success of antibody-drug conjugates (ADCs) depends on the therapeutic window rendered by the differential expression between normal and pathological tissues. The ability to identify and visualize target expression in normal tissues could reveal causes for target-mediated clearance observed in pharmacokinetic characterization. TENB2 is a prostate cancer target associated with the progression of poorly differentiated and androgen-independent tumour types, and ADCs specific for TENB2 are candidate therapeutics. The objective of this study was to locate antigen expression of TENB2 in normal tissues, thereby elucidating the underlying causes of target-mediated clearance. Experimental Approach A series of pharmacokinetics, tissue distribution and mass balance studies were conducted in mice using a radiolabelled anti-TENB2 ADC. These data were complemented by non-invasive single photon emission computed tomography – X-ray computed tomography imaging and immunohistochemistry. Key Results The intestines were identified as a saturable and specific antigen sink that contributes, at least in part, to the rapid target-mediated clearance of the anti-TENB2 antibody and its drug conjugate in rodents. As a proof of concept, we also demonstrated the selective disposition of the ADC in a tumoural environment in vivo using the LuCaP 77 transplant mouse model. High tumour uptake was observed despite the presence of the antigen sink, and antigen specificity was confirmed by antigen blockade. Conclusions and Implications Our findings provide the anatomical location and biological interpretation of target-mediated clearance of anti-TENB2 antibodies and corresponding drug conjugates. Further investigations may be beneficial in addressing the relative contributions to ADC disposition from antigen expression in both normal and pathological tissues. PMID:22889168

An integrated approach to identify normal tissue expression of targets for antibody-drug conjugates: case study of TENB2.

PubMed

Boswell, C Andrew; Mundo, Eduardo E; Firestein, Ron; Zhang, Crystal; Mao, Weiguang; Gill, Herman; Young, Cynthia; Ljumanovic, Nina; Stainton, Shannon; Ulufatu, Sheila; Fourie, Aimee; Kozak, Katherine R; Fuji, Reina; Polakis, Paul; Khawli, Leslie A; Lin, Kedan

2013-01-01

The success of antibody-drug conjugates (ADCs) depends on the therapeutic window rendered by the differential expression between normal and pathological tissues. The ability to identify and visualize target expression in normal tissues could reveal causes for target-mediated clearance observed in pharmacokinetic characterization. TENB2 is a prostate cancer target associated with the progression of poorly differentiated and androgen-independent tumour types, and ADCs specific for TENB2 are candidate therapeutics. The objective of this study was to locate antigen expression of TENB2 in normal tissues, thereby elucidating the underlying causes of target-mediated clearance. A series of pharmacokinetics, tissue distribution and mass balance studies were conducted in mice using a radiolabelled anti-TENB2 ADC. These data were complemented by non-invasive single photon emission computed tomography - X-ray computed tomography imaging and immunohistochemistry. The intestines were identified as a saturable and specific antigen sink that contributes, at least in part, to the rapid target-mediated clearance of the anti-TENB2 antibody and its drug conjugate in rodents. As a proof of concept, we also demonstrated the selective disposition of the ADC in a tumoural environment in vivo using the LuCaP 77 transplant mouse model. High tumour uptake was observed despite the presence of the antigen sink, and antigen specificity was confirmed by antigen blockade. Our findings provide the anatomical location and biological interpretation of target-mediated clearance of anti-TENB2 antibodies and corresponding drug conjugates. Further investigations may be beneficial in addressing the relative contributions to ADC disposition from antigen expression in both normal and pathological tissues. © 2012 Genentech, Inc.. British Journal of Pharmacology © 2012 The British Pharmacological Society.

CdSe/CdS semiconductor quantum rods as robust fluorescent probes for paraffin-embedded tissue imaging.

PubMed

Zacheo, Antonella; Quarta, Alessandra; Mangoni, Antonella; Pompa, Pier Paolo; Mastria, Rosanna; Capogrossi, Maurizio C; Rinaldi, Ross; Pellegrino, Teresa

2011-09-01

Immunofluorescence techniques on formalin fixed paraffin-embedded sections allow for the evaluation of the expression and spatial distribution of specific markers in patient tissue specimens or for monitoring the fate of labeled cells after in vivo injection. This technique suffers however from the auto-fluorescence background signal of the embedded tissue that eventually confounds the analysis. Here we show that rod-like semiconductor nanocrystals (QRs), intramuscularly injected in living mice, could be clearly detected by confocal microscopy in formalin fixed paraffin-embedded tissue sections. Despite the low amount of QRs amount injected (25 picomoles), these were clearly visible after 24 h in the muscle sections and their fluorescence signal was stronger than that of CdSe/ZnS quantum dots (QDs) similarly functionalized and in the case of QRs only, the signal lasted even after 21 days after the injection. © 2011 IEEE

Simultaneous Separation of Acidic and Basic Isoperoxidases in Wounded Potato Tissue by Acrylamide Gel Electrophoresis 1

PubMed Central

Borchert, Rolf; Decedue, Charles J.

1978-01-01

Preparation and use of a newly developed pH 4.3 horizontal thin layer acrylamide gel which permits the simultaneous separation of acidic and basic isoperoxidases in up to 30 samples is described. Use of cytochrome c, horseradish peroxidase, and a purified potato isoperoxidase as internal standards for a range in isoelectric points of peroxidases from pH 3 to 11 is introduced to facilitate comparison of results obtained with different materials and different methods. Distribution of tissue-specific isoperoxidases in different cell layers of wounded potato (Solanum tuberosum L.) tissue is shown and their purification described. Evidence for the in vitro degradation of basic potato isoperoxidases resulting in more acidic forms similar to isoperoxidases occurring in wounded potato tissue is presented. The significance of this observation for the postulated differential function of different isoperoxidases is discussed. ImagesFig. 1-3 PMID:16660608

VA's National PTSD Brain Bank: a National Resource for Research.

PubMed

Friedman, Matthew J; Huber, Bertrand R; Brady, Christopher B; Ursano, Robert J; Benedek, David M; Kowall, Neil W; McKee, Ann C

2017-08-25

The National PTSD Brain Bank (NPBB) is a brain tissue biorepository established to support research on the causes, progression, and treatment of PTSD. It is a six-part consortium led by VA's National Center for PTSD with participating sites at VA medical centers in Boston, MA; Durham, NC; Miami, FL; West Haven, CT; and White River Junction, VT along with the Uniformed Services University of Health Sciences. It is also well integrated with VA's Boston-based brain banks that focus on Alzheimer's disease, ALS, chronic traumatic encephalopathy, and other neurological disorders. This article describes the organization and operations of NPBB with specific attention to: tissue acquisition, tissue processing, diagnostic assessment, maintenance of a confidential data biorepository, adherence to ethical standards, governance, accomplishments to date, and future challenges. Established in 2014, NPBB has already acquired and distributed brain tissue to support research on how PTSD affects brain structure and function.

Site-specific distribution of claudin-based paracellular channels with roles in biological fluid flow and metabolism.

PubMed

Tanaka, Hiroo; Tamura, Atsushi; Suzuki, Koya; Tsukita, Sachiko

2017-10-01

The claudins are a family of membrane proteins with at least 27 members in humans and mice. The extracellular regions of claudin proteins play essential roles in cell-cell adhesion and the paracellular barrier functions of tight junctions (TJs) in epithelial cell sheets. Furthermore, the extracellular regions of some claudins function as paracellular channels in the paracellular barrier that allow the selective passage of water, ions, and/or small organic solutes across the TJ in the extracellular space. Structural analyses have revealed a common framework of transmembrane, cytoplasmic, and extracellular regions among the claudin-based paracellular barriers and paracellular channels; however, differences in the claudins' extracellular regions, such as their charges and conformations, determine their properties. Among the biological systems that involve fluid flow and metabolism, it is noted that hepatic bile flow, renal Na + reabsorption, and intestinal nutrient absorption are dynamically regulated via site-specific distributions of paracellular channel-forming claudins in tissue. Here, we focus on how site-specific distributions of claudin-2- and claudin-15-based paracellular channels drive their organ-specific functions in the liver, kidney, and intestine. © 2017 New York Academy of Sciences.

MRI-Guided Focused Ultrasound as a New Method of Drug Delivery

PubMed Central

Thanou, M.; Gedroyc, W.

2013-01-01

Ultrasound-mediated drug delivery under the guidance of an imaging modality can improve drug disposition and achieve site-specific drug delivery. The term focal drug delivery has been introduced to describe the focal targeting of drugs in tissues with the help of imaging and focused ultrasound. Focal drug delivery aims to improve the therapeutic profile of drugs by improving their specificity and their permeation in defined areas. Focused-ultrasound- (FUS-) mediated drug delivery has been applied with various molecules to improve their local distribution in tissues. FUS is applied with the aid of microbubbles to enhance the permeability of bioactive molecules across BBB and improve drug distribution in the brain. Recently, FUS has been utilised in combination with MRI-labelled liposomes that respond to temperature increase. This strategy aims to “activate” nanoparticles to release their cargo locally when triggered by hyperthermia induced by FUS. MRI-guided FUS drug delivery provides the opportunity to improve drug bioavailability locally and therefore improve the therapeutic profiles of drugs. This drug delivery strategy can be directly translated to clinic as MRg FUS is a promising clinically therapeutic approach. However, more basic research is required to understand the physiological mechanism of FUS-enhanced drug delivery. PMID:23738076

The Characteristics of Herpes Simplex Virus Type 1 Infection in Rhesus Macaques and the Associated Pathological Features.

PubMed

Fan, Shengtao; Cai, Hongzhi; Xu, Xingli; Feng, Min; Wang, Lichun; Liao, Yun; Zhang, Ying; He, Zhanlong; Yang, Fengmei; Yu, Wenhai; Wang, Jingjing; Zhou, Jumin; Li, Qihan

2017-01-30

As one of the major pathogens for human herpetic diseases, herpes simplex virus type 1 (HSV1) causes herpes labialis, genital herpes and herpetic encephalitis. Our aim here was to investigate the infectious process of HSV1 in rhesus macaques and the pathological features induced during this infection. Clinical symptoms that manifested in the rhesus macaque during HSV1 infection included vesicular lesions and their pathological features. Viral distribution in the nervous tissues and associated pathologic changes indicated the typical systematic pathological processes associated with viral distribution of HSV1.Interestingly, vesicular lesions recurred in oral skin or in mucosa associated with virus shedding in macaques within four to five months post-infection,and viral latency-associated transcript (LAT) mRNA was found in the trigeminal ganglia (TG)on day 365 post-infection. Neutralization testing and enzyme-linked immunospot (ELISpot) detection of specific T cell responses confirmed the specific immunity induced by HSV1 infection. Thus, rhesus macaques could serve as an infectious model for HSV1 due to their typical clinical symptoms and the pathological recurrence associated with viral latency in nervous tissues.

Quantitative cumulative biodistribution of antibodies in mice: effect of modulating binding affinity to the neonatal Fc receptor.

PubMed

Yip, Victor; Palma, Enzo; Tesar, Devin B; Mundo, Eduardo E; Bumbaca, Daniela; Torres, Elizabeth K; Reyes, Noe A; Shen, Ben Q; Fielder, Paul J; Prabhu, Saileta; Khawli, Leslie A; Boswell, C Andrew

2014-01-01

The neonatal Fc receptor (FcRn) plays an important and well-known role in antibody recycling in endothelial and hematopoietic cells and thus it influences the systemic pharmacokinetics (PK) of immunoglobulin G (IgG). However, considerably less is known about FcRn's role in the metabolism of IgG within individual tissues after intravenous administration. To elucidate the organ distribution and gain insight into the metabolism of humanized IgG1 antibodies with different binding affinities FcRn, comparative biodistribution studies in normal CD-1 mice were conducted. Here, we generated variants of herpes simplex virus glycoprotein D-specific antibody (humanized anti-gD) with increased and decreased FcRn binding affinity by genetic engineering without affecting antigen specificity. These antibodies were expressed in Chinese hamster ovary cell lines, purified and paired radiolabeled with iodine-125 and indium-111. Equal amounts of I-125-labeled and In-111-labeled antibodies were mixed and intravenously administered into mice at 5 mg/kg. This approach allowed us to measure both the real-time IgG uptake (I-125) and cumulative uptake of IgG and catabolites (In-111) in individual tissues up to 1 week post-injection. The PK and distribution of the wild-type IgG and the variant with enhanced binding for FcRn were largely similar to each other, but vastly different for the rapidly cleared low-FcRn-binding variant. Uptake in individual tissues varied across time, FcRn binding affinity, and radiolabeling method. The liver and spleen emerged as the most concentrated sites of IgG catabolism in the absence of FcRn protection. These data provide an increased understanding of FcRn's role in antibody PK and catabolism at the tissue level.

Quantitative cumulative biodistribution of antibodies in mice

PubMed Central

Yip, Victor; Palma, Enzo; Tesar, Devin B; Mundo, Eduardo E; Bumbaca, Daniela; Torres, Elizabeth K; Reyes, Noe A; Shen, Ben Q; Fielder, Paul J; Prabhu, Saileta; Khawli, Leslie A; Boswell, C Andrew

2014-01-01

The neonatal Fc receptor (FcRn) plays an important and well-known role in antibody recycling in endothelial and hematopoietic cells and thus it influences the systemic pharmacokinetics (PK) of immunoglobulin G (IgG). However, considerably less is known about FcRn’s role in the metabolism of IgG within individual tissues after intravenous administration. To elucidate the organ distribution and gain insight into the metabolism of humanized IgG1 antibodies with different binding affinities FcRn, comparative biodistribution studies in normal CD-1 mice were conducted. Here, we generated variants of herpes simplex virus glycoprotein D-specific antibody (humanized anti-gD) with increased and decreased FcRn binding affinity by genetic engineering without affecting antigen specificity. These antibodies were expressed in Chinese hamster ovary cell lines, purified and paired radiolabeled with iodine-125 and indium-111. Equal amounts of I-125-labeled and In-111-labeled antibodies were mixed and intravenously administered into mice at 5 mg/kg. This approach allowed us to measure both the real-time IgG uptake (I-125) and cumulative uptake of IgG and catabolites (In-111) in individual tissues up to 1 week post-injection. The PK and distribution of the wild-type IgG and the variant with enhanced binding for FcRn were largely similar to each other, but vastly different for the rapidly cleared low-FcRn-binding variant. Uptake in individual tissues varied across time, FcRn binding affinity, and radiolabeling method. The liver and spleen emerged as the most concentrated sites of IgG catabolism in the absence of FcRn protection. These data provide an increased understanding of FcRn’s role in antibody PK and catabolism at the tissue level. PMID:24572100

Subcellular localization and distribution of the reduced folate carrier in normal rat tissues.

PubMed

Hinken, M; Halwachs, S; Kneuer, C; Honscha, W

2011-01-27

The reduced folate carrier (Rfc1; Slc19a1) mediated transport of reduced folates and antifolate drugs such as methotrexate (MTX) play an essential role in physiological folate homeostasis and MTX cancer chemotherapy. As no systematic reports are as yet available correlating Rfc1 gene expression and protein levels in all tissues crucial for folate and antifolate uptake, storage or elimination, we investigated gene and protein expression of rat Rfc1 (rRfc1) in selected tissues. This included the generation of a specific anti-rRfc1 antibody. Rabbits were immunised with isolated rRfc1 peptides producing specific anti-rRfc1 antiserum targeted to the intracellular C-terminus of the carrier. Using RT-PCR analysis, high rRfc1 transcript levels were detected in colon, kidney, brain, thymus, and spleen. Moderate rRfc1 gene expression was observed in small intestine, liver, bone marrow, lung, and testes whereas transcript levels were negligible in heart, skeletal muscle or leukocytes. Immunohistochemical analyses revealed strong carrier expression in the apical membrane of tunica mucosa epithelial cells of small intestine and colon, in the brush-border membrane of choroid plexus epithelial cells or in endothelial cells of small vessels in brain and heart. Additionally, high rRfc1 protein levels were localized in the basolateral membrane of renal tubular epithelial cells, in the plasma membrane of periportal hepatocytes, and sertoli cells of the testes. Taken together, our results demonstrated that rRfc1 is expressed almost ubiquitously but to very different levels. The predominant tissue distribution supports the essential role of Rfc1 in physiological folate homeostasis. Moreover, our results may contribute to understand antifolate pharmacokinetics and selected organ toxicity associated with MTX chemotherapy.

Histological and anatomical structure of the nasal cavity of Bama minipigs

PubMed Central

Yang, Jingjing; Dai, Lei; Yu, Qinghua; Yang, Qian

2017-01-01

Objective The nasal mucosa is equipped with abundant lymphatic tissues, serving as the first line of defense against invasion by microorganisms. In this study, we characterized the features of the nasal mucosa of Bama minipigs (Sus scrofa domestica) via histological analysis. Methods Five cross sections (I, II, III, IV, and V) were obtained from the distal end of the nasal cavity toward the pharynx (along the cavity axis) and examined. Specifically, CD3+ T cells, immunoglobulin A (IgA)+ cells, and M cells were detected by immunohistochemistry, while dendritic cells (DCs) were detected by immunofluorescence. The distribution of goblet cells was determined by periodic acid-Schiff (PAS) staining. Results The nasal cavity of Bama minipigs can be divided into three parts: the regio vestibularis (I, II), regio respiratoria (III, IV), and regio olfactoria (V). Lymphoid tissue was present at random locations in the nasal cavity. Abundant lymphoid tissue was located in the roof of the nasopharyngeal meatus and was continuous with the lymphoid tissue of the pharynx. The distribution of CD3+ T cells, IgA+ cells, M cells, and DCs increased distally in the nasal cavity. Conclusions The present work comprises a histological study of the nasal cavity of Bama minipigs, and will be beneficial for understanding the mechanisms of immunity in these animals after nasal vaccination. PMID:28339502

Method for assessing the need for case-specific hemodynamics: application to the distribution of vascular permeability.

PubMed

Hazel, A L; Friedman, M H

2000-01-01

A common approach to understanding the role of hemodynamics in atherogenesis is to seek relationships between parameters of the hemodynamic environment, and the distribution of tissue variables thought to be indicative of early disease. An important question arising in such investigations is whether the distributions of tissue variables are sufficiently similar among cases to permit them to be described by an ensemble average distribution. If they are, the hemodynamic environment needs be determined only once, for a nominal representative geometry; if not, the hemodynamic environment must be obtained for each case. A method for classifying distributions from multiple cases to answer this question is proposed and applied to the distributions of the uptake of Evans blue dye labeled albumin by the external iliac arteries of swine in response to a step increase in flow. It is found that the uptake patterns in the proximal segment of the arteries, between the aortic trifurcation and the ostium of the circumflex iliac artery, show considerable case-to-case variability. In the distal segment, extending to the deep femoral ostium, many cases show very little spatial variation, and the patterns in those that do are similar among the cases. Thus the response of the distal segment may be understood with fewer simulations, but the proximal segment has more information to offer.

Methods and theory in bone modeling drift: comparing spatial analyses of primary bone distributions in the human humerus.

PubMed

Maggiano, Corey M; Maggiano, Isabel S; Tiesler, Vera G; Chi-Keb, Julio R; Stout, Sam D

2016-01-01

This study compares two novel methods quantifying bone shaft tissue distributions, and relates observations on human humeral growth patterns for applications in anthropological and anatomical research. Microstructural variation in compact bone occurs due to developmental and mechanically adaptive circumstances that are 'recorded' by forming bone and are important for interpretations of growth, health, physical activity, adaptation, and identity in the past and present. Those interpretations hinge on a detailed understanding of the modeling process by which bones achieve their diametric shape, diaphyseal curvature, and general position relative to other elements. Bone modeling is a complex aspect of growth, potentially causing the shaft to drift transversely through formation and resorption on opposing cortices. Unfortunately, the specifics of modeling drift are largely unknown for most skeletal elements. Moreover, bone modeling has seen little quantitative methodological development compared with secondary bone processes, such as intracortical remodeling. The techniques proposed here, starburst point-count and 45° cross-polarization hand-drawn histomorphometry, permit the statistical and populational analysis of human primary tissue distributions and provide similar results despite being suitable for different applications. This analysis of a pooled archaeological and modern skeletal sample confirms the importance of extreme asymmetry in bone modeling as a major determinant of microstructural variation in diaphyses. Specifically, humeral drift is posteromedial in the human humerus, accompanied by a significant rotational trend. In general, results encourage the usage of endocortical primary bone distributions as an indicator and summary of bone modeling drift, enabling quantitative analysis by direction and proportion in other elements and populations. © 2015 Anatomical Society.

[Report on notifications according to section 8d of the German Transplantation Act (TPG) for the years 2009-2011].

PubMed

Schilling-Leiß, D; Witt, F; Tönjes, R R

2014-01-01

In Germany, the Tissue Act came into effect on 1 August 2007. Since then, every tissue establishment is legally obligated to keep a record of its activities according to section 8d subsection 3 of the Transplantation Act (TPG). An annual report must be submitted to the Paul Ehrlich Institute once a year up to 1 March of the subsequent year. The report should include the types and quantities of tissues procured, conditioned, processed, stored, distributed or otherwise disposed of, imported, and exported. The report should be made on a TPG-based notification form published on the Internet by the Paul Ehrlich Institute. The present report according to section 8d subsection 3 of the TPG is based on data of the reporting years 2009-2011. Six years after implementation of the TPG's reporting obligation for tissue establishments, the number of tissue establishments known by the Paul Ehrlich Institute has increased from 349 in 2007 to 949 in 2011. In the course of continuous optimization of the notification forms, including tissue-specific glossaries, the reported data of most of the tissues and tissue preparations have become more conclusive.

Fast probing of glucose and fructose in plant tissues via plasmonic affinity sandwich assay with molecularly-imprinted extraction microprobes.

PubMed

Muhammad, Pir; Liu, Jia; Xing, Rongrong; Wen, Yanrong; Wang, Yijia; Liu, Zhen

2017-12-01

Determination of specific target compounds in agriculture food and natural plant products is essential for many purposes; however, it is often challenging due to the complexity of the sample matrices. Herein we present a new approach called plasmonic affinity sandwich assay for the facile and rapid probing of glucose and fructose in plant tissues. The approach mainly relies on molecularly imprinted plasmonic extraction microprobes, which were prepared on gold-coated acupuncture needles via boronate affinity controllable oriented surface imprinting with the target monosaccharide as the template molecules. An extraction microprobe was inserted into plant tissues under investigation, which allowed for the specific extraction of glucose or fructose from the tissues. The glucose or fructose molecules extracted on the microprobe were labeled with boronic acid-functionalized Raman-active silver nanoparticles, and thus affinity sandwich complexes were formed on the microprobes. After excess Raman nanotags were washed away, the microprobe was subjected to Raman detection. Upon being irradiated with a laser beam, surface plasmon on the gold-coated microprobes was generated, which further produced plasmon-enhanced Raman scattering of the silver-based nanotags and thereby provided sensitive detection. Apple fruits, which contain abundant glucose and fructose, were used as a model of plant tissues. The approach exhibited high specificity, good sensitivity (limit of detection, 1 μg mL -1 ), and fast speed (the whole procedure required only 20 min). The spatial distribution profiles of glucose and fructose within an apple were investigated by the developed approach. Copyright © 2017 Elsevier B.V. All rights reserved.

A Numerical Investigation of the Electric and Thermal Cell Kill Distributions in Electroporation-Based Therapies in Tissue

PubMed Central

Garcia, Paulo A.; Davalos, Rafael V.; Miklavcic, Damijan

2014-01-01

Electroporation-based therapies are powerful biotechnological tools for enhancing the delivery of exogeneous agents or killing tissue with pulsed electric fields (PEFs). Electrochemotherapy (ECT) and gene therapy based on gene electrotransfer (EGT) both use reversible electroporation to deliver chemotherapeutics or plasmid DNA into cells, respectively. In both ECT and EGT, the goal is to permeabilize the cell membrane while maintaining high cell viability in order to facilitate drug or gene transport into the cell cytoplasm and induce a therapeutic response. Irreversible electroporation (IRE) results in cell kill due to exposure to PEFs without drugs and is under clinical evaluation for treating otherwise unresectable tumors. These PEF therapies rely mainly on the electric field distributions and do not require changes in tissue temperature for their effectiveness. However, in immediate vicinity of the electrodes the treatment may results in cell kill due to thermal damage because of the inhomogeneous electric field distribution and high current density during the electroporation-based therapies. Therefore, the main objective of this numerical study is to evaluate the influence of pulse number and electrical conductivity in the predicted cell kill zone due to irreversible electroporation and thermal damage. Specifically, we simulated a typical IRE protocol that employs ninety 100-µs PEFs. Our results confirm that it is possible to achieve predominant cell kill due to electroporation if the PEF parameters are chosen carefully. However, if either the pulse number and/or the tissue conductivity are too high, there is also potential to achieve cell kill due to thermal damage in the immediate vicinity of the electrodes. Therefore, it is critical for physicians to be mindful of placement of electrodes with respect to critical tissue structures and treatment parameters in order to maintain the non-thermal benefits of electroporation and prevent unnecessary damage to surrounding healthy tissue, critical vascular structures, and/or adjacent organs. PMID:25115970

Quantitative differentiation of breast lesions at 3T diffusion-weighted imaging (DWI) using the ratio of distributed diffusion coefficient (DDC).

PubMed

Ertas, Gokhan; Onaygil, Can; Akin, Yasin; Kaya, Handan; Aribal, Erkin

2016-12-01

To investigate the accuracy of diffusion coefficients and diffusion coefficient ratios of breast lesions and of glandular breast tissue from mono- and stretched-exponential models for quantitative diagnosis in diffusion-weighted magnetic resonance imaging (MRI). We analyzed pathologically confirmed 170 lesions (85 benign and 85 malignant) imaged using a 3.0T MR scanner. Small regions of interest (ROIs) focusing on the highest signal intensity for lesions and also for glandular tissue of contralateral breast were obtained. Apparent diffusion coefficient (ADC) and distributed diffusion coefficient (DDC) were estimated by performing nonlinear fittings using mono- and stretched-exponential models, respectively. Coefficient ratios were calculated by dividing the lesion coefficient by the glandular tissue coefficient. A stretched exponential model provides significantly better fits then the monoexponential model (P < 0.001): 65% of the better fits for glandular tissue and 71% of the better fits for lesion. High correlation was found in diffusion coefficients (0.99-0.81 and coefficient ratios (0.94) between the models. The highest diagnostic accuracy was found by the DDC ratio (area under the curve [AUC] = 0.93) when compared with lesion DDC, ADC ratio, and lesion ADC (AUC = 0.91, 0.90, 0.90) but with no statistically significant difference (P > 0.05). At optimal thresholds, the DDC ratio achieves 93% sensitivity, 80% specificity, and 87% overall diagnostic accuracy, while ADC ratio leads to 89% sensitivity, 78% specificity, and 83% overall diagnostic accuracy. The stretched exponential model fits better with signal intensity measurements from both lesion and glandular tissue ROIs. Although the DDC ratio estimated by using the model shows a higher diagnostic accuracy than the ADC ratio, lesion DDC, and ADC, it is not statistically significant. J. Magn. Reson. Imaging 2016;44:1633-1641. © 2016 International Society for Magnetic Resonance in Medicine.

Arginase distribution in tissues of domestic animals.

PubMed

Aminlari, M; Vaseghi, T

1992-10-01

1. A new colorimetric method was used for determination of arginase in different tissues of some domestic animals. 2. In all species studied liver was the richest source of arginase. 3. Significant differences were observed in the specific activity of arginase in livers from different species. 4. In all species, besides liver, kidney and brain also contained significant levels of arginase. 5. In the dog, in addition to the three organs mentioned above, lung, heart, spleen and skeletal muscle showed some arginase activity. 6. In sheep and cattle significant arginase activity was observed in the rumen. No differences were observed between epithelial and muscular layers of different parts of digestive system in all species studied. 7. These results are discussed in terms of the possible role of arginase in different tissues of animals.

Proteoglycan: collagen interactions in connective tissues. Ultrastructural, biochemical, functional and evolutionary aspects.

PubMed

Scott, J E

1991-06-01

Electron histochemical investigations of mammalian and echinoderm tissues, using cupromeronic blue to stain proteoglycans (PGs) specifically in critical electrolyte concentration methods, showed that collagen fibrils are associated with keratan sulphate and chondroitin (dermatan) sulphate ('tadpole') PGs at the a, c, d and e bands on the fibril surface, giving rise to the 'one proteoglycan: one binding site' hypothesis. Intra-fibrillar PGs have been observed, distributed in a regular way which suggests that collagen fibrils are aggregates of 'protofibrils', some of which carry PGs at their surfaces. A scheme for remodelling of collagen fibrils, based on recycling of these protofibrils, is outlined. The choice of which tadpole PG to use to carry out a given function is decided to a considerable extent by the availability of oxygen to the relevant tissue element.

Expressed sequence tags from poplar wood tissues--a comparative analysis from multiple libraries.

PubMed

Déjardin, A; Leplé, J-C; Lesage-Descauses, M-C; Costa, G; Pilate, G

2004-01-01

Xylogenesis involves successive developmental processes--cambial division, cell expansion and differentiation, cell death--each occurring along a gradient from the cambium to the pith of the stem. Taking advantage of the high level of organisation of wood tissues, we isolated cambial zone (CZ), differentiating xylem (DX) and mature xylem (MX) from both tension wood (TW) and opposite wood (OW) of bent poplars. Four different cDNA libraries were then constructed and used to generate 10,062 EST, reflecting the genes expressed in the different wood tissues. For the most abundant clusters, the EST distributions were compared between libraries in order to identify genes specific or over-represented at some specific developmental stages. They clearly showed a developmental shift between CZ and DX, whereas there is a continuity of development between DX and MX. CZ was mainly characterized by clusters of genes involved in cell cycle, protein synthesis and fate. Interestingly, two clusters with no assigned function were found specific to the cambial zone. In DX and MX, clusters were mostly involved in methylation of lignin precursors and microtubule cytoskeleton. In addition, in DX, EST from TW and OW were compared: five clusters of arabinogalactan proteins, one for sucrose synthase and one for fructokinase were specific or over-represented in TW. Moreover, a putative transcription factor and a cluster of unknown function were also identified in DX-TW. The informative comparison of multiple libraries prepared from wood tissues led to the identification of genes--some with still unknown functions--putatively involved in xylogenesis and tension wood formation.

The Human EST Ontology Explorer: a tissue-oriented visualization system for ontologies distribution in human EST collections.

PubMed

Merelli, Ivan; Caprera, Andrea; Stella, Alessandra; Del Corvo, Marcello; Milanesi, Luciano; Lazzari, Barbara

2009-10-15

The NCBI dbEST currently contains more than eight million human Expressed Sequenced Tags (ESTs). This wide collection represents an important source of information for gene expression studies, provided it can be inspected according to biologically relevant criteria. EST data can be browsed using different dedicated web resources, which allow to investigate library specific gene expression levels and to make comparisons among libraries, highlighting significant differences in gene expression. Nonetheless, no tool is available to examine distributions of quantitative EST collections in Gene Ontology (GO) categories, nor to retrieve information concerning library-dependent EST involvement in metabolic pathways. In this work we present the Human EST Ontology Explorer (HEOE) http://www.itb.cnr.it/ptp/human_est_explorer, a web facility for comparison of expression levels among libraries from several healthy and diseased tissues. The HEOE provides library-dependent statistics on the distribution of sequences in the GO Direct Acyclic Graph (DAG) that can be browsed at each GO hierarchical level. The tool is based on large-scale BLAST annotation of EST sequences. Due to the huge number of input sequences, this BLAST analysis was performed with the aid of grid computing technology, which is particularly suitable to address data parallel task. Relying on the achieved annotation, library-specific distributions of ESTs in the GO Graph were inferred. A pathway-based search interface was also implemented, for a quick evaluation of the representation of libraries in metabolic pathways. EST processing steps were integrated in a semi-automatic procedure that relies on Perl scripts and stores results in a MySQL database. A PHP-based web interface offers the possibility to simultaneously visualize, retrieve and compare data from the different libraries. Statistically significant differences in GO categories among user selected libraries can also be computed. The HEOE provides an alternative and complementary way to inspect EST expression levels with respect to approaches currently offered by other resources. Furthermore, BLAST computation on the whole human EST dataset was a suitable test of grid scalability in the context of large-scale bioinformatics analysis. The HEOE currently comprises sequence analysis from 70 non-normalized libraries, representing a comprehensive overview on healthy and unhealthy tissues. As the analysis procedure can be easily applied to other libraries, the number of represented tissues is intended to increase.

Quantitative mapping of elemental distribution in leaves of the metallophytes Helichrysum candolleanum, Blepharis aspera, and Blepharis diversispina from Selkirk Cu-Ni mine, Botswana

NASA Astrophysics Data System (ADS)

Koosaletse-Mswela, Pulane; Przybyłowicz, Wojciech J.; Cloete, Karen J.; Barnabas, Alban D.; Torto, Nelson; Mesjasz-Przybyłowicz, Jolanta

2015-11-01

Multi-element profiling is essential in understanding the metal-tolerant behavior of metallophytes. Although previous reports using multi-elemental analyses show that the metallophytes Blepharis aspera, Blepharis diversispina (Acanthaceae) and Helichrysum candolleanum (Asteraceae) take up metals, no information exists on elemental spatial distribution and concentrations in specific tissues of these plants. The aim of this study therefore was to assess the spatial distribution and concentration of copper, nickel and other elements in leaf tissues of these plants using micro-PIXE. Whole plants were collected with soil in pots from an operational copper and nickel mine (i.e., a copper and nickel mineralized area), Selkirk, about 40 km north-east of Francistown, Botswana. On the same day the samples were transported by air to iThemba LABS in South Africa. Leaf specimens were cryofixed in liquid propane cooled by LN2. Parallel samples were embedded in resin for anatomical studies to facilitate interpretation of elemental maps. The distribution and concentration of copper, nickel, and other elements in leaf tissues were determined using micro-PIXE and proton backscattering spectrometry. Data evaluation was performed using GeoPIXE II software. Micro-PIXE showed that H. candolleanum had the highest whole leaf content of copper (70 ± 3 μg g-1 DW) and nickel (168 ± 5 μg g-1 DW), followed by B. aspera (Cu: 25 ± 1 μg g-1 DW; Ni: 166 ± 4 μg g-1 DW) and B. diversispina (Cu: 3 ± 1 μg g-1 DW; Ni, below detection limit). For specific leaf tissues, the highest levels of copper were found in the vascular bundle for H. candolleanum (167 ± 7 μg g-1 DW) and the lower epidermis for B. aspera (70 ± 9 μg g-1 DW). The highest levels of nickel were present in the vascular bundle of B. aspera (479 ± 10 μg g-1 DW) and H. candolleanum (90 ± 5 μg g-1 DW). Elemental maps showed a similar distribution pattern for copper and nickel in B. aspera and B diversispina, with these elements concentrated in the upper and lower epidermal regions. However, for H. candolleanum, both copper and nickel were concentrated in the mesophyll. The difference in concentration and accumulation patterns between B. aspera, B. diversispina and H. candolleanum suggests that the metal-tolerant adaptation of these metallophytes may differ.

Use of Synchrotron X-ray Fluorescence to Measure Trace Metal Distribution in the Brain

NASA Astrophysics Data System (ADS)

Linkous, D.; Flinn, J. M.; Lanzirotti, A.; Frederickson, C.; Jones, B. F.; Bertsch, P. M.

2002-12-01

X26A, National Synchrotron Light Source, was used to quantitatively evaluate the spatial distribution of trace metals, such as Zn and Cu, in brain tissue. X-ray microprobe techniques offer distinct advantages over other analytical methods by allowing analyses to be done in-situ with little or no chemical pretreatment and low detection limits (about 1 ppm). In the context of neuroscience, SXRF can provide non-destructive measurements of specific metal concentrations and distribution within nerve (brain) tissue. Neuronal tissue from organisms having undergone different normal or experimental conditions may be compared, with analytical capacities not limited by binding states of the metal (i.e., vesicular or enzymatic), as is the case with staining techniques.. Whole regions of tissue may be scanned for detectable trace metals at spatial resolutions of 10um or less using focused monochromatic x-ray beams. Here special attention has been given to zinc because it is the most common trace metal in the brain, and levels have been increasing in the environment. In this investigation, zinc concentrations present within the hilus of a rat hippocampus, and to a lesser extent in the cortex, have been shown to increase following long-term ingestion of zinc-enhanced drinking water that was associated with deficits in spatial memory. Concomitantly, copper concentrations in the internal capsule were comparatively lower. Other first order transition metals, Cr, V, Mn, and Co were not detected. In contrast, elevated levels of Zn, Cu, and Fe have been seen in amyloid plaques associated with Alzheimer's disease.

Marqibo® (vincristine sulfate liposome injection) improves the pharmacokinetics and pharmacodynamics of vincristine.

PubMed

Silverman, Jeffrey A; Deitcher, Steven R

2013-03-01

Vincristine (VCR) is a mainstay of treatment of hematologic malignancies and solid tumors due to its well-defined mechanism of action, demonstrated anticancer activity and its ability to be combined with other agents. VCR is an M-phase cell cycle-specific anticancer drug with activity that is concentration and exposure duration dependent. The pharmacokinetic profile of standard VCR is described by a bi-exponential elimination pattern with a very fast initial distribution half-life followed by a longer elimination half-life. VCR also has a large volume of distribution, suggesting diffuse distribution and tissue binding. These properties may limit optimal drug exposure and delivery to target tissues as well as clinical utility as a single agent or as an effective component of multi-agent regimens. Vincristine sulfate liposome injection (VSLI), Marqibo(®), is a sphingomyelin and cholesterol-based nanoparticle formulation of VCR that was designed to overcome the dosing and pharmacokinetic limitations of standard VCR. VSLI was developed to increase the circulation time, optimize delivery to target tissues and facilitate dose intensification without increasing toxicity. In xenograft studies in mice, VSLI had a higher maximum tolerated dose, superior antitumor activity and delivered higher amounts of active drug to target tissues compared to standard VCR. VSLI recently received accelerated FDA approval for use in adults with advanced, relapsed and refractory Philadelphia chromosome-negative ALL and is in development for untreated adult ALL, pediatric ALL and untreated aggressive NHL. Here, we summarize the nonclinical data for VSLI that support its continued clinical development and recent approval for use in adult ALL.

Comparative glycan profiling of Ceratopteris richardii ‘C-Fern’ gametophytes and sporophytes links cell-wall composition to functional specialization

PubMed Central

Eeckhout, Sharon; Leroux, Olivier; Willats, William G. T.; Popper, Zoë A.; Viane, Ronald L. L.

2014-01-01

Background and Aims Innovations in vegetative and reproductive characters were key factors in the evolutionary history of land plants and most of these transformations, including dramatic changes in life cycle structure and strategy, necessarily involved cell-wall modifications. To provide more insight into the role of cell walls in effecting changes in plant structure and function, and in particular their role in the generation of vascularization, an antibody-based approach was implemented to compare the presence and distribution of cell-wall glycan epitopes between (free-living) gametophytes and sporophytes of Ceratopteris richardii ‘C-Fern’, a widely used model system for ferns. Methods Microarrays of sequential diamino-cyclohexane-tetraacetic acid (CDTA) and NaOH extractions of gametophytes, spores and different organs of ‘C-Fern’ sporophytes were probed with glycan-directed monoclonal antibodies. The same probes were employed to investigate the tissue- and cell-specific distribution of glycan epitopes. Key Results While monoclonal antibodies against pectic homogalacturonan, mannan and xyloglucan widely labelled gametophytic and sporophytic tissues, xylans were only detected in secondary cell walls of the sporophyte. The LM5 pectic galactan epitope was restricted to sporophytic phloem tissue. Rhizoids and root hairs showed similarities in arabinogalactan protein (AGP) and xyloglucan epitope distribution patterns. Conclusions The differences and similarities in glycan cell-wall composition between ‘C-Fern’ gametophytes and sporophytes indicate that the molecular design of cell walls reflects functional specialization rather than genetic origin. Glycan epitopes that were not detected in gametophytes were associated with cell walls of specialized tissues in the sporophyte. PMID:24699895

A Derivatization and Validation Strategy for Determining the Spatial Localization of Endogenous Amine Metabolites in Tissues using MALDI Imaging Mass Spectrometry

PubMed Central

Manier, M. Lisa; Spraggins, Jeffrey M.; Reyzer, Michelle L.; Norris, Jeremy L.; Caprioli, Richard M.

2014-01-01

Imaging mass spectrometry (IMS) studies increasingly focus on endogenous small molecular weight metabolites and consequently bring special analytical challenges. Since analytical tissue blanks do not exist for endogenous metabolites, careful consideration must be given to confirm molecular identity. Here we present approaches for the improvement in detection of endogenous amine metabolites such as amino acids and neurotransmitters in tissues through chemical derivatization and matrix-assisted laser desorption/ionization (MALDI) IMS. Chemical derivatization with 4-hydroxy-3-methoxycinnamaldehyde (CA) was used to improve sensitivity and specificity. CA was applied to the tissue via MALDI sample targets precoated with a mixture of derivatization reagent and ferulic acid (FA) as a MALDI matrix. Spatial distributions of chemically derivatized endogenous metabolites in tissue were determined by high-mass resolution and MSn imaging mass spectrometry. We highlight an analytical strategy for metabolite validation whereby tissue extracts are analyzed by high-performance liquid chromatography (HPLC)-MS/MS to unambiguously identify metabolites and distinguish them from isobaric compounds. PMID:25044893

Analysis of DNA-vaccinated fish reveals viral antigen in muscle, kidney, and thymus, and transient histopathologic changes

USGS Publications Warehouse

Garver, K.A.; Conway, C.M.; Elliott, D.G.; Kurath, G.

2005-01-01

A highly efficacious DNA vaccine against a fish rhabdovirus, infectious hematopoietic necrosis virus (IHNV), was used in a systematic study to analyze vaccine tissue distribution, persistence, expression patterns, and histopathologic effects. Vaccine plasmid pIHNw-G, containing the gene for the viral glycoprotein, was detected immediately after intramuscular injection in all tissues analyzed, including blood, but at later time points was found primarily in muscle tissue, where it persisted to 90 days. Glycoprotein expression was detected in muscle, kidney, and thymus tissues, with levels peaking at 14 days and becoming undetectable by 28 days. Histologic examination revealed no vaccine-specific pathologic changes at the standard effective dose of 0.1 ??g DNA per fish, but at a high dose of 50 ??g an increased inflammatory response was evident. Transient damage associated with needle injection was localized in muscle tissue, but by 90 days after vaccination no damage was detected in any tissue, indicating the vaccine to be safe and well tolerated. ?? Springer Science+Business Media, Inc. 2005.

Linear energy transfer incorporated intensity modulated proton therapy optimization

NASA Astrophysics Data System (ADS)

Cao, Wenhua; Khabazian, Azin; Yepes, Pablo P.; Lim, Gino; Poenisch, Falk; Grosshans, David R.; Mohan, Radhe

2018-01-01

The purpose of this study was to investigate the feasibility of incorporating linear energy transfer (LET) into the optimization of intensity modulated proton therapy (IMPT) plans. Because increased LET correlates with increased biological effectiveness of protons, high LETs in target volumes and low LETs in critical structures and normal tissues are preferred in an IMPT plan. However, if not explicitly incorporated into the optimization criteria, different IMPT plans may yield similar physical dose distributions but greatly different LET, specifically dose-averaged LET, distributions. Conventionally, the IMPT optimization criteria (or cost function) only includes dose-based objectives in which the relative biological effectiveness (RBE) is assumed to have a constant value of 1.1. In this study, we added LET-based objectives for maximizing LET in target volumes and minimizing LET in critical structures and normal tissues. Due to the fractional programming nature of the resulting model, we used a variable reformulation approach so that the optimization process is computationally equivalent to conventional IMPT optimization. In this study, five brain tumor patients who had been treated with proton therapy at our institution were selected. Two plans were created for each patient based on the proposed LET-incorporated optimization (LETOpt) and the conventional dose-based optimization (DoseOpt). The optimized plans were compared in terms of both dose (assuming a constant RBE of 1.1 as adopted in clinical practice) and LET. Both optimization approaches were able to generate comparable dose distributions. The LET-incorporated optimization achieved not only pronounced reduction of LET values in critical organs, such as brainstem and optic chiasm, but also increased LET in target volumes, compared to the conventional dose-based optimization. However, on occasion, there was a need to tradeoff the acceptability of dose and LET distributions. Our conclusion is that the inclusion of LET-dependent criteria in the IMPT optimization could lead to similar dose distributions as the conventional optimization but superior LET distributions in target volumes and normal tissues. This may have substantial advantages in improving tumor control and reducing normal tissue toxicities.

Geometry Design Optimization of Functionally Graded Scaffolds for Bone Tissue Engineering: A Mechanobiological Approach.

PubMed

Boccaccio, Antonio; Uva, Antonio Emmanuele; Fiorentino, Michele; Mori, Giorgio; Monno, Giuseppe

2016-01-01

Functionally Graded Scaffolds (FGSs) are porous biomaterials where porosity changes in space with a specific gradient. In spite of their wide use in bone tissue engineering, possible models that relate the scaffold gradient to the mechanical and biological requirements for the regeneration of the bony tissue are currently missing. In this study we attempt to bridge the gap by developing a mechanobiology-based optimization algorithm aimed to determine the optimal graded porosity distribution in FGSs. The algorithm combines the parametric finite element model of a FGS, a computational mechano-regulation model and a numerical optimization routine. For assigned boundary and loading conditions, the algorithm builds iteratively different scaffold geometry configurations with different porosity distributions until the best microstructure geometry is reached, i.e. the geometry that allows the amount of bone formation to be maximized. We tested different porosity distribution laws, loading conditions and scaffold Young's modulus values. For each combination of these variables, the explicit equation of the porosity distribution law-i.e the law that describes the pore dimensions in function of the spatial coordinates-was determined that allows the highest amounts of bone to be generated. The results show that the loading conditions affect significantly the optimal porosity distribution. For a pure compression loading, it was found that the pore dimensions are almost constant throughout the entire scaffold and using a FGS allows the formation of amounts of bone slightly larger than those obtainable with a homogeneous porosity scaffold. For a pure shear loading, instead, FGSs allow to significantly increase the bone formation compared to a homogeneous porosity scaffolds. Although experimental data is still necessary to properly relate the mechanical/biological environment to the scaffold microstructure, this model represents an important step towards optimizing geometry of functionally graded scaffolds based on mechanobiological criteria.

Tissue-specific expression of the gene coding for human Clara cell 10-kD protein, a phospholipase A2-inhibitory protein.

PubMed Central

Peri, A; Cordella-Miele, E; Miele, L; Mukherjee, A B

1993-01-01

Clara cell 10-kD protein (cc10kD), a secretory phospholipase A2 inhibitor, is suggested to be the human counterpart of rabbit uteroglobin (UG). Because cc10kD is expressed constitutively at a very high level in the human respiratory epithelium, the 5' region of its gene may be useful in achieving organ-specific expression of recombinant DNA in gene therapy of diseases such as cystic fibrosis. However, it is important to establish the tissue-specific expression of this gene before designing gene transfer experiments. Since the UG gene in the rabbit is expressed in many other organs besides the lung and the endometrium, we investigated the organ and tissue specificity of human cc10kD gene expression using polymerase chain reaction, nucleotide sequence analysis, immunofluorescence, and Northern blotting. Our results indicate that, in addition to the lung, cc10kD is expressed in several nonrespiratory organs, with a distribution pattern very similar, if not identical, to that of UG in the rabbit. These results underscore the necessity for more detailed analyses of the 5' region of the human cc10kD gene before its usefulness in gene therapy could be fully assessed. These data also suggest that cc10kD and UG may have similar physiological function(s). Images PMID:8227325

Three-Dimensional Imaging of the Intracellular Fate of Plasmid DNA and Transgene Expression: ZsGreen1 and Tissue Clearing Method CUBIC Are an Optimal Combination for Multicolor Deep Imaging in Murine Tissues.

PubMed

Fumoto, Shintaro; Nishimura, Koyo; Nishida, Koyo; Kawakami, Shigeru

2016-01-01

Evaluation methods for determining the distribution of transgene expression in the body and the in vivo fate of viral and non-viral vectors are necessary for successful development of in vivo gene delivery systems. Here, we evaluated the spatial distribution of transgene expression using tissue clearing methods. After hydrodynamic injection of plasmid DNA into mice, whole tissues were subjected to tissue clearing. Tissue clearing followed by confocal laser scanning microscopy enabled evaluation of the three-dimensional distribution of transgene expression without preparation of tissue sections. Among the tested clearing methods (ClearT2, SeeDB, and CUBIC), CUBIC was the most suitable method for determining the spatial distribution of transgene expression in not only the liver but also other tissues such as the kidney and lung. In terms of the type of fluorescent protein, the observable depth for green fluorescent protein ZsGreen1 was slightly greater than that for red fluorescent protein tdTomato. We observed a depth of ~1.5 mm for the liver and 500 μm for other tissues without preparation of tissue sections. Furthermore, we succeeded in multicolor deep imaging of the intracellular fate of plasmid DNA in the murine liver. Thus, tissue clearing would be a powerful approach for determining the spatial distribution of plasmid DNA and transgene expression in various murine tissues.

Constitutive formulations for the mechanical investigation of colonic tissues.

PubMed

Carniel, Emanuele Luigi; Gramigna, Vera; Fontanella, Chiara Giulia; Stefanini, Cesare; Natali, Arturo N

2014-05-01

A constitutive framework is provided for the characterization of the mechanical behavior of colonic tissues, as a fundamental tool for the development of numerical models of the colonic structures. The constitutive analysis is performed by a multidisciplinary approach that requires the cooperation between experimental and computational competences. The preliminary investigation pertains to the review of the tissues histology. The complex structural configuration of the tissues and the specific distributions of fibrous elements entail the nonlinear mechanical behavior and the anisotropic response. The identification of the mechanical properties requires to perform mechanical tests according to different loading situations, as different loading directions. Because of the typical functionality of colon structures, the tissues mechanics is investigated by tensile tests, which are performed on taenia coli and haustra specimens from fresh pig colons. Accounting for the histological investigation and the results from the mechanical tests, a specific hyperelastic framework is provided within the theory of fiber-reinforced composite materials. Preliminary analytical formulations are defined to identify the constitutive parameters by the inverse analysis of the experimental tests. Finite element models of the specimens are developed accounting for the actual configuration of the colon structures to verify the quality of the results. The good agreement between experimental and numerical model results suggests the reliability of the constitutive formulations and parameters. Finally, the developed constitutive analysis makes it possible to identify the mechanical behavior and properties of the different colonic tissues. Copyright © 2013 Wiley Periodicals, Inc.

Enhanced distribution and extended elimination of glycyrrhetinic acid in mice liver by mPEG-PLA modified (mPEGylated) liposome.

PubMed

Li, Juan; Yu, Hua; Li, Shuai; Wang, Guang Ji

2010-04-06

A rapid and simple method of high-performance liquid chromatography with UV detector for the quantification of glycyrrhetinic acid (GA) in mice plasma and tissues has been developed and validated. With the established assay method, the pharmacokinetic profiles and tissue distribution of GA in different formulations are compared in mice after intravenous administration of the drug (25mg/kg). The results showed that mPEG-PLA modified (mPEGylated) GA liposome (PL-GA) significantly prolonged the mean residence time (MRT) of GA in mice plasma and liver (MRT: 0.43+/-0.13 and 1.72+/-0.11h, respectively) than the normal GA liposome (L-GA) (MRT: 0.23+/-0.01 and 1.07+/-0.31h, respectively) and GA sodium injection (S-GA) (MRT: 0.13+/-0.01 and 0.95+/-0.08h, respectively). Moreover, PL-GA specifically increased GA uptake in liver (AUC(0-infinity,)(liver) value of 1.6-fold and 1.3-fold higher than that for S-GA and L-GA, respectively) and reduced its distribution into other tissues after dosing. Due to these pharmacokinetic properties, it may be promising to develop PL-GA further as a new pharmaceutical preparation for GA on the treatment of various chronic hepatic diseases. Copyright 2009. Published by Elsevier B.V.

MURC/Cavin-4 and cavin family members form tissue-specific caveolar complexes

PubMed Central

Bastiani, Michele; Liu, Libin; Hill, Michelle M.; Jedrychowski, Mark P.; Nixon, Susan J.; Lo, Harriet P.; Abankwa, Daniel; Luetterforst, Robert; Fernandez-Rojo, Manuel; Breen, Michael R.; Gygi, Steven P.; Vinten, Jorgen; Walser, Piers J.; North, Kathryn N.; Hancock, John F.; Pilch, Paul F.

2009-01-01

Polymerase I and transcript release factor (PTRF)/Cavin is a cytoplasmic protein whose expression is obligatory for caveola formation. Using biochemistry and fluorescence resonance energy transfer–based approaches, we now show that a family of related proteins, PTRF/Cavin-1, serum deprivation response (SDR)/Cavin-2, SDR-related gene product that binds to C kinase (SRBC)/Cavin-3, and muscle-restricted coiled-coil protein (MURC)/Cavin-4, forms a multiprotein complex that associates with caveolae. This complex can constitutively assemble in the cytosol and associate with caveolin at plasma membrane caveolae. Cavin-1, but not other cavins, can induce caveola formation in a heterologous system and is required for the recruitment of the cavin complex to caveolae. The tissue-restricted expression of cavins suggests that caveolae may perform tissue-specific functions regulated by the composition of the cavin complex. Cavin-4 is expressed predominantly in muscle, and its distribution is perturbed in human muscle disease associated with Caveolin-3 dysfunction, identifying Cavin-4 as a novel muscle disease candidate caveolar protein. PMID:19546242

Global adiposity and thickness of intraperitoneal and mesenteric adipose tissue depots are increased in women with polycystic ovary syndrome (PCOS).

PubMed

Borruel, Susana; Fernández-Durán, Elena; Alpañés, Macarena; Martí, David; Alvarez-Blasco, Francisco; Luque-Ramírez, Manuel; Escobar-Morreale, Héctor F

2013-03-01

Sexual dimorphism suggests a role for androgens in body fat distribution. Women with polycystic ovary syndrome (PCOS), a mainly androgen excess disorder, often present with abdominal obesity and visceral adiposity. We hypothesized that women with PCOS have a masculinized body fat distribution favoring the deposition of fat in visceral and organ-specific adipose tissue depots. This was a case-control study. The study was conducted at an academic hospital. Women with PCOS (n = 55), women without androgen excess (n = 25), and men (n = 26) presenting with similar body mass index participated in the study. There were no interventions. Ultrasound measurements of adipose tissue depots including sc (minimum and maximum), preperitoneal, ip, mesenteric, epicardial, and perirenal fat thickness were obtained and total body fat mass was estimated using a body fat monitor. Men and patients with PCOS had increased amounts of total body fat compared with control women. Men had increased thickness of intraabdominal adipose tissue depots compared with the control women, with the women with PCOS showing intermediate values that were also higher than those of control women in the case of ip and mesenteric fat thickness and was close to reaching statistical significance in the case of epicardial fat thickness. Women with PCOS also showed increased minimum sc fat thickness compared with the control women. Obesity increased the thickness of all of the adipose tissue depots in the 3 groups of subjects. Women with PCOS have higher global adiposity and increased amounts of visceral adipose tissue compared with control women, especially in the ip and mesenteric depots.

Evidence for age-dependent air-space enlargement contributing to loss of lung tissue elastic recoil pressure and increased shear modulus in older age.

PubMed

Subramaniam, K; Kumar, H; Tawhai, M H

2017-07-01

As a normal part of mature aging, lung tissue undergoes microstructural changes such as alveolar air-space enlargement and redistribution of collagen and elastin away from the alveolar duct. The older lung also experiences an associated decrease in elastic recoil pressure and an increase in specific tissue elastic moduli, but how this relates mechanistically to microstructural remodeling is not well-understood. In this study, we use a structure-based mechanics analysis to elucidate the contributions of age-related air-space enlargement and redistribution of elastin and collagen to loss of lung elastic recoil pressure and increase in tissue elastic moduli. Our results show that age-related geometric changes can result in reduction of elastic recoil pressure and increase in shear and bulk moduli, which is consistent with published experimental data. All elastic moduli were sensitive to the distribution of stiffness (representing elastic fiber density) in the alveolar wall, with homogenous stiffness near the duct and through the septae resulting in a more compliant tissue. The preferential distribution of elastic proteins around the alveolar duct in the healthy young adult lung therefore provides for a more elastic tissue. NEW & NOTEWORTHY We use a structure-based mechanics analysis to correlate air-space enlargement and redistribution of elastin and collagen to age-related changes in the mechanical behavior of lung parenchyma. Our study highlights that both the cause (redistribution of elastin and collagen) and the structural effect (alveolar air-space enlargement) contribute to decline in lung tissue elastic recoil with age; these results are consistent with published data and provide a new avenue for understanding the mechanics of the older lung. Copyright © 2017 the American Physiological Society.

Detection of Metastatic Breast and Thyroid Cancer in Lymph Nodes by Desorption Electrospray Ionization Mass Spectrometry Imaging

NASA Astrophysics Data System (ADS)

Zhang, Jialing; Feider, Clara L.; Nagi, Chandandeep; Yu, Wendong; Carter, Stacey A.; Suliburk, James; Cao, Hop S. Tran; Eberlin, Livia S.

2017-06-01

Ambient ionization mass spectrometry has been widely applied to image lipids and metabolites in primary cancer tissues with the purpose of detecting and understanding metabolic changes associated with cancer development and progression. Here, we report the use of desorption electrospray ionization mass spectrometry (DESI-MS) to image metastatic breast and thyroid cancer in human lymph node tissues. Our results show clear alterations in lipid and metabolite distributions detected in the mass spectra profiles from 42 samples of metastatic thyroid tumors, metastatic breast tumors, and normal lymph node tissues. 2D DESI-MS ion images of selected molecular species allowed discrimination and visualization of specific histologic features within tissue sections, including regions of metastatic cancer, adjacent normal lymph node, and fibrosis or adipose tissues, which strongly correlated with pathologic findings. In thyroid cancer metastasis, increased relative abundances of ceramides and glycerophosphoinisitols were observed. In breast cancer metastasis, increased relative abundances of various fatty acids and specific glycerophospholipids were seen. Trends in the alterations in fatty acyl chain composition of lipid species were also observed through detailed mass spectra evaluation and chemical identification of molecular species. The results obtained demonstrate DESI-MSI as a potential clinical tool for the detection of breast and thyroid cancer metastasis in lymph nodes, although further validation is needed. [Figure not available: see fulltext.

Tissue-specific accumulation of cadmium in subcellular compartments of eastern oysters Crassostrea virginica Gmelin (Bivalvia: Ostreidae).

PubMed

Sokolova, I M; Ringwood, A H; Johnson, C

2005-09-10

Cadmium distribution was studied in different subcellular fractions of gill and hepatopancreas tissues of eastern oysters Crassostrea virginica. Oysters were exposed for up to 21 days to low sublethal Cd concentrations (25 microg L(-1)). Gill and hepatopancreas tissues were sampled and divided into organelle fractions and cytosol by differential centrifugation. Organelle content of different fractions was verified by activities of marker enzymes, citrate synthase and acid phosphatase for mitochondria and lysosomes, respectively. In both tissue types, there was a significant accumulation of cadmium in cytosol reaching 230-350 ng mg(-1) protein. Among organelles, mitochondria were the main target for Cd bioaccumulation in gills (250-300 ng mg(-1) protein), whereas in hepatopancreas tissues, the highest cadmium accumulation occurred in lysosomes (90-94 ng mg(-1) protein). Although 75-83% of total cadmium burden was associated with the cytosol reflecting high volume fraction of this compartment, Cd concentrations in organelle fractions reached levels that could cause dysfunction of mitochondria and lysosomes. Organ- and organelle-specific patterns of cadmium bioaccumulation support our previous in vivo studies, which showed adverse effects of cadmium exposures on mitochondrial oxidation in gills and on the lysosomal system of hepatopancreas. This may have important implications for the development of biomarkers of effect for heavy metals and for understanding the mechanisms of toxic effects of metals.

Distinct roles for Ste20-like kinase SLK in muscle function and regeneration

PubMed Central

2013-01-01

Background Cell growth and terminal differentiation are controlled by complex signaling systems that regulate the tissue-specific expression of genes controlling cell fate and morphogenesis. We have previously reported that the Ste20-like kinase SLK is expressed in muscle tissue and is required for cell motility. However, the specific function of SLK in muscle tissue is still poorly understood. Methods To gain further insights into the role of SLK in differentiated muscles, we expressed a kinase-inactive SLK from the human skeletal muscle actin promoter. Transgenic muscles were surveyed for potential defects. Standard histological procedures and cardiotoxin-induced regeneration assays we used to investigate the role of SLK in myogenesis and muscle repair. Results High levels of kinase-inactive SLK in muscle tissue produced an overall decrease in SLK activity in muscle tissue, resulting in altered muscle organization, reduced litter sizes, and reduced breeding capacity. The transgenic mice did not show any differences in fiber-type distribution but displayed enhanced regeneration capacity in vivo and more robust differentiation in vitro. Conclusions Our results show that SLK activity is required for optimal muscle development in the embryo and muscle physiology in the adult. However, reduced kinase activity during muscle repair enhances regeneration and differentiation. Together, these results suggest complex and distinct roles for SLK in muscle development and function. PMID:23815977

The prediction of blood-tissue partitions, water-skin partitions and skin permeation for agrochemicals.

PubMed

Abraham, Michael H; Gola, Joelle M R; Ibrahim, Adam; Acree, William E; Liu, Xiangli

2014-07-01

There is considerable interest in the blood-tissue distribution of agrochemicals, and a number of researchers have developed experimental methods for in vitro distribution. These methods involve the determination of saline-blood and saline-tissue partitions; not only are they indirect, but they do not yield the required in vivo distribution. The authors set out equations for gas-tissue and blood-tissue distribution, for partition from water into skin and for permeation from water through human skin. Together with Abraham descriptors for the agrochemicals, these equations can be used to predict values for all of these processes. The present predictions compare favourably with experimental in vivo blood-tissue distribution where available. The predictions require no more than simple arithmetic. The present method represents a much easier and much more economic way of estimating blood-tissue partitions than the method that uses saline-blood and saline-tissue partitions. It has the added advantages of yielding the required in vivo partitions and being easily extended to the prediction of partition of agrochemicals from water into skin and permeation from water through skin. © 2013 Society of Chemical Industry.

STUDIES ON THE DISTRIBUTION AND PHOSPHATE TURNOVER OF THE ACID-SOLUBLE PHOSPHORUS COMPOUNDS IN VARIOUS NORMAL AND NEOPLASTIC TISSUES OF RATS. II. COMPARISON OF THE CHROMATOGRAMS OBTAINED WITH VARIOUS TISSUES INCLUDING TUMOURS (ENGLISH TEXT)

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

Horie, S.

Using a modified semi-micro gradient elution method of chromatography, the distribution of the acid-soluble nucleotides in various normal and neoplastic tissues of rats was compared and the variations of the distribution are described. The distribution and phosphate turnover of the acid-soluble phosphorus compounds were also studied by intraperitoneal injection of P/sup 32/ followed by the chromatographic analysis. The distribution patterns of nucleotides and radioactivity in liver, muscle, heart, lung, thymus, spleen, testicles, brain, fetal liver, and experimental hepatomas are illustrated and the differences between these tissues were pointed out. The characteristics of the experimental hepatoma tissue as compared with themore » normal liver tissue are as follows: The concentration of oxidized DPN was low; the incorporation of P/sup 32/ inorganic phosphate into glucose 6-phosphate and L- alpha -glycerophosphate was absent or, if any, very low; radioactivity of inorganic phosphate in the total acid-soluble radioactivity was extraordinarily high as compared with other tissues besides the liver tissue. (Abstr. Japan Med., 1: No. 9, 1961)« less

Antibodies to the Core Proteins of Nairobi Sheep Disease Virus/Ganjam Virus Reveal Details of the Distribution of the Proteins in Infected Cells and Tissues

PubMed Central

Lasecka, Lidia; Bin-Tarif, Abdelghani; Bridgen, Anne; Juleff, Nicholas; Waters, Ryan A.; Baron, Michael D.

2015-01-01

Nairobi sheep disease virus (NSDV; also called Ganjam virus in India) is a bunyavirus of the genus Nairovirus. It causes a haemorrhagic gastroenteritis in sheep and goats with mortality up to 90%. The virus is closely related to the human pathogen Crimean-Congo haemorrhagic fever virus (CCHFV). Little is currently known about the biology of NSDV. We have generated specific antibodies against the virus nucleocapsid protein (N) and polymerase (L) and used these to characterise NSDV in infected cells and to study its distribution during infection in a natural host. Due to its large size and the presence of a papain-like protease (the OTU-like domain) it has been suggested that the L protein of nairoviruses undergoes an autoproteolytic cleavage into polymerase and one or more accessory proteins. Specific antibodies which recognise either the N-terminus or the C-terminus of the NSDV L protein showed no evidence of L protein cleavage in NSDV-infected cells. Using the specific anti-N and anti-L antibodies, it was found that these viral proteins do not fully colocalise in infected cells; the N protein accumulated near the Golgi at early stages of infection while the L protein was distributed throughout the cytoplasm, further supporting the multifunctional nature of the L protein. These antibodies also allowed us to gain information about the organs and cell types targeted by the virus in vivo. We could detect NSDV in cryosections prepared from various tissues collected post-mortem from experimentally inoculated animals; the virus was found in the mucosal lining of the small and large intestine, in the lungs, and in mesenteric lymph nodes (MLN), where NSDV appeared to target monocytes and/or macrophages. PMID:25905707

Antibodies to the core proteins of Nairobi sheep disease virus/Ganjam virus reveal details of the distribution of the proteins in infected cells and tissues.

PubMed

Lasecka, Lidia; Bin-Tarif, Abdelghani; Bridgen, Anne; Juleff, Nicholas; Waters, Ryan A; Baron, Michael D

2015-01-01

Nairobi sheep disease virus (NSDV; also called Ganjam virus in India) is a bunyavirus of the genus Nairovirus. It causes a haemorrhagic gastroenteritis in sheep and goats with mortality up to 90%. The virus is closely related to the human pathogen Crimean-Congo haemorrhagic fever virus (CCHFV). Little is currently known about the biology of NSDV. We have generated specific antibodies against the virus nucleocapsid protein (N) and polymerase (L) and used these to characterise NSDV in infected cells and to study its distribution during infection in a natural host. Due to its large size and the presence of a papain-like protease (the OTU-like domain) it has been suggested that the L protein of nairoviruses undergoes an autoproteolytic cleavage into polymerase and one or more accessory proteins. Specific antibodies which recognise either the N-terminus or the C-terminus of the NSDV L protein showed no evidence of L protein cleavage in NSDV-infected cells. Using the specific anti-N and anti-L antibodies, it was found that these viral proteins do not fully colocalise in infected cells; the N protein accumulated near the Golgi at early stages of infection while the L protein was distributed throughout the cytoplasm, further supporting the multifunctional nature of the L protein. These antibodies also allowed us to gain information about the organs and cell types targeted by the virus in vivo. We could detect NSDV in cryosections prepared from various tissues collected post-mortem from experimentally inoculated animals; the virus was found in the mucosal lining of the small and large intestine, in the lungs, and in mesenteric lymph nodes (MLN), where NSDV appeared to target monocytes and/or macrophages.

Evaluation of specimen preparation techniques for micro-PIXE localisation of elements in hyperaccumulating plants

NASA Astrophysics Data System (ADS)

Kachenko, Anthony G.; Siegele, Rainer; Bhatia, Naveen P.; Singh, Balwant; Ionescu, Mihail

2008-04-01

Hybanthus floribundus subsp. floribundus, a rare Australian Ni-hyperaccumulating shrub and Pityrogramma calomelanos var. austroamericana, an Australian naturalized As-hyperaccumulating fern are promising species for use in phytoremediation of contaminated sites. Micro-proton-induced X-ray emission (μ-PIXE) spectroscopy was used to map the elemental distribution of the accumulated metal(loid)s, Ca and K in leaf or pinnule tissues of the two plant species. Samples were prepared by two contrasting specimen preparation techniques: freeze-substitution in tetrahydrofuran (THF) and freeze-drying. The specimens were analysed to compare the suitability of each technique in preserving (i) the spatial elemental distribution and (ii) the tissue structure of the specimens. Further, the μ-PIXE results were compared with concentration of elements in the bulk tissue obtained by ICP-AES analysis. In H. floribundus subsp. floribundus, μ-PIXE analysis revealed Ni, Ca and K concentrations in freeze-dried leaf tissues were at par with bulk tissue concentrations. Elemental distribution maps illustrated that Ni was preferentially localised in the adaxial epidermal tissues (1% DW) and least concentration was found in spongy mesophyll tissues (0.53% DW). Conversely, elemental distribution maps of THF freeze-substituted tissues indicated significantly lower Ni, Ca and K concentrations than freeze-dried specimens and bulk tissue concentrations. Moreover, Ni concentrations were uniform across the whole specimen and no localisation was observed. In P. calomelanos var. austroamericana freeze-dried pinnule tissues, μ-PIXE revealed statistically similar As, Ca and K concentrations as compared to bulk tissue concentrations. Elemental distribution maps showed that As localisation was relatively uniform across the whole specimen. Once again, THF freeze-substituted tissues revealed a significant loss of As compared to freeze-dried specimens and the concentrations obtained by bulk tissue analysis. The results demonstrate that freeze-drying is a suitable sample preparation technique to study elemental distribution of ions in H. floribundus and P. calomelanos plant tissues using μ-PIXE spectroscopy. Furthermore, cellular structure was preserved in samples prepared using this technique.

Metabolic syndrome: is equine disease comparable to what we know in humans?

PubMed Central

Ertelt, Antonia; Barton, Ann-Kristin; Schmitz, Robert R; Gehlen, Heidrun

2014-01-01

This review summarizes similarities and differences between the metabolic syndromes in humans and equines, concerning the anatomy, symptoms, and pathophysiological mechanisms. In particular, it discusses the structure and distribution of adipose tissue and its specific metabolic pathways. Furthermore, this article provides insights and focuses on issues concerning laminitis in horses and cardiovascular diseases in humans, as well as their overlap. PMID:24894908

PCR assay detects Mannheimia haemolytica in culture-negative pneumonic lung tissues of bighorn sheep (Ovis canadensis) from outbreaks in the western USA, 2009-2010.

PubMed

Shanthalingam, Sudarvili; Goldy, Andrea; Bavananthasivam, Jegarubee; Subramaniam, Renuka; Batra, Sai Arun; Kugadas, Abirami; Raghavan, Bindu; Dassanayake, Rohana P; Jennings-Gaines, Jessica E; Killion, Halcyon J; Edwards, William H; Ramsey, Jennifer M; Anderson, Neil J; Wolff, Peregrine L; Mansfield, Kristin; Bruning, Darren; Srikumaran, Subramaniam

2014-01-01

Mannheimia haemolytica consistently causes severe bronchopneumonia and rapid death of bighorn sheep (Ovis canadensis) under experimental conditions. However, Bibersteinia trehalosi and Pasteurella multocida have been isolated from pneumonic bighorn lung tissues more frequently than M. haemolytica by culture-based methods. We hypothesized that assays more sensitive than culture would detect M. haemolytica in pneumonic lung tissues more accurately. Therefore, our first objective was to develop a PCR assay specific for M. haemolytica and use it to determine if this organism was present in the pneumonic lungs of bighorns during the 2009-2010 outbreaks in Montana, Nevada, and Washington, USA. Mannheimia haemolytica was detected by the species-specific PCR assay in 77% of archived pneumonic lung tissues that were negative by culture. Leukotoxin-negative M. haemolytica does not cause fatal pneumonia in bighorns. Therefore, our second objective was to determine if the leukotoxin gene was also present in the lung tissues as a means of determining the leukotoxicity of M. haemolytica that were present in the lungs. The leukotoxin-specific PCR assay detected leukotoxin gene in 91% of lung tissues that were negative for M. haemolytica by culture. Mycoplasma ovipneumoniae, an organism associated with bighorn pneumonia, was detected in 65% of pneumonic bighorn lung tissues by PCR or culture. A PCR assessment of distribution of these pathogens in the nasopharynx of healthy bighorns from populations that did not experience an all-age die-off in the past 20 yr revealed that M. ovipneumoniae was present in 31% of the animals whereas leukotoxin-positive M. haemolytica was present in only 4%. Taken together, these results indicate that culture-based methods are not reliable for detection of M. haemolytica and that leukotoxin-positive M. haemolytica was a predominant etiologic agent of the pneumonia outbreaks of 2009-2010.

[Study of susceptibility weighted imaging on MR and pathologic findings to distinguish benign or malignant soft tissue tumor].

PubMed

Liu, J; Chen, Y; Bao, X M; Ling, X L; Ding, J P; Zhang, Z K

2017-05-23

Objective: To explore the diagnostic performance of susceptibility weighted imaging (SWI)in distinguishing benign or malignant soft tissue tumor, and to study pathological observation. Methods: Sixty-eight patients with soft tissue tumor, who received no previous treatment or invasive examination, received routine preoperative MRI examination and SWI scanning. The graduation and distribution of intratumoral susceptibility signal intensity(ITSS) and proportion of tumor volume were observed.The pathological results were also included for comparative analysis. Results: Fourty of 68 patients were benign and 28 were malignant. 72.5% (29/40) patients with benign soft tissue tumors were ITSS grade 1 and ITSS grade 3 (hemangioma). 89.3%(25/28) patients with malignant soft tissue tumors were ITSS grade 2 and ITSS grade 3. The difference was statistically significant ( P <0.01). The distribution of ITSS in patients with benign soft tissue tumors was dominated by peripheral distribution and diffuse distribution (hemangioma), accounting for 90.0% (36/40). The distribution of ITSS in patients with malignant soft tissue tumors mainly distributed in the central region, accounting for 78.6% (22 /28). The difference was statistically significant ( P <0.01). The proportion of tumor volume occupied by ITSS in benign soft tissue tumors was <1/3 and> 2/3 (hemangioma), accounting for 90.0% (36/40). The volume of malignant soft tissue tumors were predominantly <1/3 , accounting for 82.1% (23/28). The difference was statistically significant ( P <0.01). Conclusion: SWI is sensitive in displaying the vein and blood metabolites in soft tissue lesions, which is helpful for the differential diagnosis of benign and malignant tumors in soft tissue.

Quantification of photoacoustic microscopy images for ovarian cancer detection

NASA Astrophysics Data System (ADS)

Wang, Tianheng; Yang, Yi; Alqasemi, Umar; Kumavor, Patrick D.; Wang, Xiaohong; Sanders, Melinda; Brewer, Molly; Zhu, Quing

2014-03-01

In this paper, human ovarian tissues with malignant and benign features were imaged ex vivo by using an opticalresolution photoacoustic microscopy (OR-PAM) system. Several features were quantitatively extracted from PAM images to describe photoacoustic signal distributions and fluctuations. 106 PAM images from 18 human ovaries were classified by applying those extracted features to a logistic prediction model. 57 images from 9 ovaries were used as a training set to train the logistic model, and 49 images from another 9 ovaries were used to test our prediction model. We assumed that if one image from one malignant ovary was classified as malignant, it is sufficient to classify this ovary as malignant. For the training set, we achieved 100% sensitivity and 83.3% specificity; for testing set, we achieved 100% sensitivity and 66.7% specificity. These preliminary results demonstrate that PAM could be extremely valuable in assisting and guiding surgeons for in vivo evaluation of ovarian tissue.

Photoacoustic imaging of vascular networks in transgenic mice

NASA Astrophysics Data System (ADS)

Laufer, J. G.; Cleary, J. O.; Zhang, E. Z.; Lythgoe, M. F.; Beard, P. C.

2010-02-01

The preferential absorption of near infrared light by blood makes photoacoustic imaging well suited to visualising vascular structures in soft tissue. In addition, the spectroscopic specificity of tissue chromophores can be exploited by acquiring images at multiple excitation wavelengths. This allows the quantification of endogenous chromophores, such as oxy- and deoxyhaemoglobin, and hence blood oxygenation, and the detection of exogenous chromophores, such as functionalised contrast agents. More importantly, this approach has the potential to visualise the spatial distribution of low concentrations of functionalised contrast agents against the strong background absorption of the endogenous chromophores. This has a large number of applications in the life sciences. One example is the structural and functional phenotyping of transgenic mice for the study of the genetic origins of vascular malformations, such as heart defects. In this study, photoacoustic images of mouse embryos have been acquired to study the development of the vasculature following specific genetic knockouts.

Quantitative detection of multiple fluorophore sites as a tool for diagnosis and monitoring disease progression in salivary glands

NASA Astrophysics Data System (ADS)

Gannot, Israel; Bonner, Robert F.; Gannot, Gallya; Fox, Philip C.; You, Joon S.; Waynant, Ronald W.; Gandjbakhche, Amir H.

1997-08-01

A series of fluorescent surface images were obtained from physical models of localized fluorophores embedded at various depths and separations in tissue phantoms. Our random walk theory was applied to create an analytical model of multiple flurophores embedded in tissue-like phantom. Using this model, from acquired set of surface images, the location of the fluorophores was reconstructed and compared it to their known 3-D distributions. A good correlation was found, and the ability to resolve fluorophores as a function of depth and separation was determined. In parallel in in-vitro study, specific coloring of sections of minor salivary glands was also demonstrated. These results demonstrate the possibility of using inverse methods to reconstruct unknown locations and concentrations of optical probes specifically bound to infiltrating lymphocytes in minor salivary glands of patients with Sjogren's syndrome.

Hydrophilization of synthetic biodegradable polymer scaffolds for improved cell/tissue compatibility.

PubMed

Oh, Se Heang; Lee, Jin Ho

2013-02-01

Porous scaffolds have been widely used in tissue engineering because they can guide cells and tissues to grow, synthesize extracellular matrix and other biological molecules, and facilitate the formation of functional tissues and organs. Although various natural and synthetic biodegradable polymers have been used to fabricate the scaffolds, synthetic polymers have been more widely used for scaffolds since they have good mechanical strength, reproducible/controllable mechanical-chemical properties, and controllable biodegradation rates. However, the 'hydrophobic character' of common synthetic polymers is considered a limitation for tissue engineering applications because it can lead to a low initial cell seeding density, heterogeneous cell distribution in the scaffold, and slow cell growth due to insufficient absorption/diffusion of cell culture medium into scaffold and lack of specific interaction sites with cells. The hydrophilization of porous synthetic polymer scaffolds has been considered as one of the simple but effective approaches to achieve desirable in vitro cell culture and in vivo tissue regeneration within the scaffolds. In this review paper, representative synthetic biodegradable polymers and techniques to fabricate porous scaffolds are briefly summarized and their hydrophilization techniques to improve cell/tissue compatibility are discussed.

Selenium Preferentially Accumulates in the Eye Lens Following Embryonic Exposure: A Confocal X-ray Fluorescence Imaging Study

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

Choudhury, Sanjukta; Thomas, Jith; Sylvain, Nicole J.

Maternal transfer of elevated selenium (Se) to offspring is an important route of Se exposure for fish in the natural environment. However, there is a lack of information on the tissue specific spatial distribution and speciation of Se in the early developmental stages of fish, which provide important information about Se toxicokinetics. The effect of maternal transfer of Se was studied by feeding adult zebrafish a Se-elevated or a control diet followed by collection of larvae from both groups. Novel confocal synchrotron-based techniques were used to investigate Se within intact preserved larvae. Confocal X-ray fluorescence imaging was used to comparemore » Se distributions within specific planes of an intact larva from each of the two groups. The elevated Se treatment showed substantially higher Se levels than the control; Se preferentially accumulated to highest levels in the eye lens, with lower levels in the retina, yolk and other tissues. Confocal X-ray absorption spectroscopy was used to determine that the speciation of Se within the eye lens of the intact larva was a selenomethionine-like species. Preferential accumulation of Se in the eye lens may suggest a direct cause-and-effect relationship between exposure to elevated Se and Se-induced ocular impairments reported previously. This study illustrates the effectiveness of confocal X-ray fluorescence methods for investigating trace element distribution and speciation in intact biological specimens« less

Flat-panel cone-beam CT: a novel imaging technology for image-guided procedures

NASA Astrophysics Data System (ADS)

Siewerdsen, Jeffrey H.; Jaffray, David A.; Edmundson, Gregory K.; Sanders, W. P.; Wong, John W.; Martinez, Alvaro A.

2001-05-01

The use of flat-panel imagers for cone-beam CT signals the emergence of an attractive technology for volumetric imaging. Recent investigations demonstrate volume images with high spatial resolution and soft-tissue visibility and point to a number of logistical characteristics (e.g., open geometry, volume acquisition in a single rotation about the patient, and separation of the imaging and patient support structures) that are attractive to a broad spectrum of applications. Considering application to image-guided (IG) procedures - specifically IG therapies - this paper examines the performance of flat-panel cone-beam CT in relation to numerous constraints and requirements, including time (i.e., speed of image acquisition), dose, and field-of-view. The imaging and guidance performance of a prototype flat panel cone-beam CT system is investigated through the construction of procedure-specific tasks that test the influence of image artifacts (e.g., x-ray scatter and beam-hardening) and volumetric imaging performance (e.g., 3D spatial resolution, noise, and contrast) - taking two specific examples in IG brachytherapy and IG vertebroplasty. For IG brachytherapy, a procedure-specific task is constructed which tests the performance of flat-panel cone-beam CT in measuring the volumetric distribution of Pd-103 permanent implant seeds in relation to neighboring bone and soft-tissue structures in a pelvis phantom. For IG interventional procedures, a procedure-specific task is constructed in the context of vertebroplasty performed on a cadaverized ovine spine, demonstrating the volumetric image quality in pre-, intra-, and post-therapeutic images of the region of interest and testing the performance of the system in measuring the volumetric distribution of bone cement (PMMA) relative to surrounding spinal anatomy. Each of these tasks highlights numerous promising and challenging aspects of flat-panel cone-beam CT applied to IG procedures.

Computer Simulations of the Tumor Vasculature: Applications to Interstitial Fluid Flow, Drug Delivery, and Oxygen Supply.

PubMed

Welter, Michael; Rieger, Heiko

2016-01-01

Tumor vasculature, the blood vessel network supplying a growing tumor with nutrients such as oxygen or glucose, is in many respects different from the hierarchically organized arterio-venous blood vessel network in normal tissues. Angiogenesis (the formation of new blood vessels), vessel cooption (the integration of existing blood vessels into the tumor vasculature), and vessel regression remodel the healthy vascular network into a tumor-specific vasculature. Integrative models, based on detailed experimental data and physical laws, implement, in silico, the complex interplay of molecular pathways, cell proliferation, migration, and death, tissue microenvironment, mechanical and hydrodynamic forces, and the fine structure of the host tissue vasculature. With the help of computer simulations high-precision information about blood flow patterns, interstitial fluid flow, drug distribution, oxygen and nutrient distribution can be obtained and a plethora of therapeutic protocols can be tested before clinical trials. This chapter provides an overview over the current status of computer simulations of vascular remodeling during tumor growth including interstitial fluid flow, drug delivery, and oxygen supply within the tumor. The model predictions are compared with experimental and clinical data and a number of longstanding physiological paradigms about tumor vasculature and intratumoral solute transport are critically scrutinized.

SU-E-T-409: Evaluation of Tissue Composition Effect On Dose Distribution in Radiotherapy with 6 MV Photon Beam of a Medical Linac

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

Ghorbani, M; Tabatabaei, Z; Noghreiyan, A Vejdani

Purpose: The aim of this study is to evaluate soft tissue composition effect on dose distribution for various soft tissues and various depths in radiotherapy with 6 MV photon beam of a medical linac. Methods: A phantom and Siemens Primus linear accelerator were simulated using MCNPX Monte Carlo code. In a homogeneous cubic phantom, six types of soft tissue and three types of tissue-equivalent materials were defined separately. The soft tissues were muscle (skeletal), adipose tissue, blood (whole), breast tissue, soft tissue (9-component) and soft tissue (4-component). The tissue-equivalent materials included: water, A-150 tissue-equivalent plastic and perspex. Photon dose relativemore » to dose in 9-component soft tissue at various depths on the beam’s central axis was determined for the 6 MV photon beam. The relative dose was also calculated and compared for various MCNPX tallies including,F8, F6 and,F4. Results: The results of the relative photon dose in various materials relative to dose in 9-component soft tissue and using different tallies are reported in the form of tabulated data. Minor differences between dose distributions in various soft tissues and tissue-equivalent materials were observed. The results from F6 and F4 were practically the same but different with,F8 tally. Conclusion: Based on the calculations performed, the differences in dose distributions in various soft tissues and tissue-equivalent materials are minor but they could be corrected in radiotherapy calculations to upgrade the accuracy of the dosimetric calculations.« less

Does atrial natriuretic factor protect against right ventricular overload II. Tissue binding

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

Ou, L.C.; Yen, S.; Sardella, G.L.

1989-10-01

Previous studies have led us to hypothesize that the physiological significance of the diuretic and pulmonary vaso-relaxant effects of atrial natriuretic factor (ANF) is to protect the right heart. This study was designed to evaluate the relative importance of various peripheral tissues as sites of ANF action by tracing the temporal pattern of distribution of {sup 125}I-ANF and quantitating the specific binding sites. An in vivo approach, utilizing trace amount of {sup 125}I-ANF was adopted to simulate physiological conditions. {sup 125}I-ANF injected either intravenously or intra-arterially was quickly bound to peripheral tissues with less than 5% remaining in the circulationmore » after 1 min. The relative binding capacity was greatest in the lung, followed by the kidney, right ventricle, adrenal gland, and left ventricle. The magnitude of specific ANF binding sites per gram of tissue weight followed a similar order. The data demonstrate that ANF released under all circumstances is quickly bound to the target organs, particularly the lung and the kidney, and suggest that these two organs could be the most important target organs of ANF. This evidence provides further support for the proposed hypothesis that a major evolutionary role of ANF is the protection of the right ventricle from mechanical loads.« less

TH-CD-206-01: Expectation-Maximization Algorithm-Based Tissue Mixture Quantification for Perfusion MRI

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

Han, H; Xing, L; Liang, Z

Purpose: To investigate the feasibility of estimating the tissue mixture perfusions and quantifying cerebral blood flow change in arterial spin labeled (ASL) perfusion MR images. Methods: The proposed perfusion MR image analysis framework consists of 5 steps: (1) Inhomogeneity correction was performed on the T1- and T2-weighted images, which are available for each studied perfusion MR dataset. (2) We used the publicly available FSL toolbox to strip off the non-brain structures from the T1- and T2-weighted MR images. (3) We applied a multi-spectral tissue-mixture segmentation algorithm on both T1- and T2-structural MR images to roughly estimate the fraction of eachmore » tissue type - white matter, grey matter and cerebral spinal fluid inside each image voxel. (4) The distributions of the three tissue types or tissue mixture across the structural image array are down-sampled and mapped onto the ASL voxel array via a co-registration operation. (5) The presented 4-dimensional expectation-maximization (4D-EM) algorithm takes the down-sampled three tissue type distributions on perfusion image data to generate the perfusion mean, variance and percentage images for each tissue type of interest. Results: Experimental results on three volunteer datasets demonstrated that the multi-spectral tissue-mixture segmentation algorithm was effective to initialize tissue mixtures from T1- and T2-weighted MR images. Compared with the conventional ASL image processing toolbox, the proposed 4D-EM algorithm not only generated comparable perfusion mean images, but also produced perfusion variance and percentage images, which the ASL toolbox cannot obtain. It is observed that the perfusion contribution percentages may not be the same as the corresponding tissue mixture volume fractions estimated in the structural images. Conclusion: A specific application to brain ASL images showed that the presented perfusion image analysis method is promising for detecting subtle changes in tissue perfusions, which is valuable for the early diagnosis of certain brain diseases, e.g. multiple sclerosis.« less

A 915-MHz antenna for microwave thermal ablation treatment: physical design, computer modeling and experimental measurement.

PubMed

Pisa, S; Cavagnaro, M; Bernardi, P; Lin, J C

2001-05-01

A 915-MHz antenna design that produces specific absorption rate distributions with preferential power deposition in tissues surrounding and including the distal end of the catheter antenna is described. The design features minimal reflected microwave current from the antenna flowing up the transmission line. This cap-choke antenna consists of an annular cap and a coaxial choke which matches the antenna to the coaxial transmission line. The design minimizes heating of the coaxial cable and its performance is not affected by the depth of insertion of the antenna into tissue. The paper provides a comparison of results obtained from computer modeling and experimental measurements made in tissue equivalent phantom materials. There is excellent agreement between numerical modeling and experimental measurement. The cap-choke, matched-dipole type antenna is suitable for intracavitary microwave thermal ablation therapy.

MRI-induced heating of deep brain stimulation leads

NASA Astrophysics Data System (ADS)

Mohsin, Syed A.; Sheikh, Noor M.; Saeed, Usman

2008-10-01

The radiofrequency (RF) field used in magnetic resonance imaging is scattered by medical implants. The scattered field of a deep brain stimulation lead can be very intense near the electrodes stimulating the brain. The effect is more pronounced if the lead behaves as a resonant antenna. In this paper, we examine the resonant length effect. We also use the finite element method to compute the near field for (i) the lead immersed in inhomogeneous tissue (fat, muscle, and brain tissues) and (ii) the lead connected to an implantable pulse generator. Electric field, specific absorption rate and induced temperature rise distributions have been obtained in the brain tissue surrounding the electrodes. The worst-case scenario has been evaluated by neglecting the effect of blood perfusion. The computed values are in good agreement with in vitro measurements made in the laboratory.

Mapping the subcellular distribution of biomolecules at the ultrastructural level by ion microscopy.

PubMed

Galle, P; Escaig, F; Dantin, F; Zhang, L

1996-05-01

Analytical ion microscopy, a method proposed and developed in 1960 by Casting and Slodzian at the Orsay University (France), makes it possible to obtain easily and rapidly analytical images representing the distribution in a tissue section of elements or isotopes (beginning from the three isotopes of hydrogen until to transuranic elements), even when these elements or isotopes are at a trace concentration of 1 ppm or less. This method has been applied to study the subcellular distribution of different varieties of biomolecules. The subcellular location of these molecules can be easily determined when the molecules contain in their structures a specific atom such as fluorine, iodine, bromine or platinum, what is the case of many pharmaceutical drugs. In this situation, the distribution of these specific atoms can be considered as representative of the distribution of the corresponding molecule. In other cases, the molecules must be labelled with an isotope which may be either radioactive or stable. Recent developments in ion microscopy allow the obtention of their chemical images at ultra structural level. In this paper we present the results obtained with the prototype of a new Scanning Ion Microscope used for the study of the intracellular distribution of different varieties of molecules: glucocorticoids, estrogens, pharmaceutical drugs and pyrimidine analogues.

Distribution of the anticancer drugs doxorubicin, mitoxantrone and topotecan in tumors and normal tissues.

PubMed

Patel, Krupa J; Trédan, Olivier; Tannock, Ian F

2013-07-01

Pharmacokinetic analyses estimate the mean concentration of drug within a given tissue as a function of time, but do not give information about the spatial distribution of drugs within that tissue. Here, we compare the time-dependent spatial distribution of three anticancer drugs within tumors, heart, kidney, liver and brain. Mice bearing various xenografts were treated with doxorubicin, mitoxantrone or topotecan. At various times after injection, tumors and samples of heart, kidney, liver and brain were excised. Within solid tumors, the distribution of doxorubicin, mitoxantrone and topotecan was limited to perivascular regions at 10 min after administration and the distance from blood vessels at which drug intensity fell to half was ~25-75 μm. Although drug distribution improved after 3 and 24 h, there remained a significant decrease in drug fluorescence with increasing distance from tumor blood vessels. Drug distribution was relatively uniform in the heart, kidney and liver with substantially greater perivascular drug uptake than in tumors. There was significantly higher total drug fluorescence in the liver than in tumors after 10 min, 3 and 24 h. Little to no drug fluorescence was observed in the brain. There are marked differences in the spatial distributions of three anticancer drugs within tumor tissue and normal tissues over time, with greater exposure to most normal tissues and limited drug distribution to many cells in tumors. Studies of the spatial distribution of drugs are required to complement pharmacokinetic data in order to better understand and predict drug effects and toxicities.

mRNA Quantification of NIPBL Isoforms A and B in Adult and Fetal Human Tissues, and a Potentially Pathological Variant Affecting Only Isoform A in Two Patients with Cornelia de Lange Syndrome

PubMed Central

Puisac, Beatriz; Teresa-Rodrigo, María-Esperanza; Hernández-Marcos, María; Baquero-Montoya, Carolina; Gil-Rodríguez, María-Concepción; Visnes, Torkild; Bot, Christopher; Gómez-Puertas, Paulino; Kaiser, Frank J.; Ramos, Feliciano J.; Ström, Lena; Pié, Juan

2017-01-01

Cornelia de Lange syndrome (CdLS) is a congenital developmental disorder characterized by craniofacial dysmorphia, growth retardation, limb malformations, and intellectual disability. Approximately 60% of patients with CdLS carry a recognizable pathological variant in the NIPBL gene, of which two isoforms, A and B, have been identified, and which only differ in the C-terminal segment. In this work, we describe the distribution pattern of the isoforms A and B mRNAs in tissues of adult and fetal origin, by qPCR (quantitative polymerase chain reaction). Our results show a higher gene expression of the isoform A, even though both seem to have the same tissue distribution. Interestingly, the expression in fetal tissues is higher than that of adults, especially in brain and skeletal muscle. Curiously, the study of fibroblasts of two siblings with a mild CdLS phenotype and a pathological variant specific of the isoform A of NIPBL (c.8387A > G; P.Tyr2796Cys), showed a similar reduction in both isoforms, and a normal sensitivity to DNA damage. Overall, these results suggest that the position of the pathological variant at the 3´ end of the NIPBL gene affecting only isoform A, is likely to be the cause of the atypical mild phenotype of the two brothers. PMID:28241484

The pea SAD short-chain dehydrogenase/reductase: quinone reduction, tissue distribution, and heterologous expression.

PubMed

Scherbak, Nikolai; Ala-Häivälä, Anneli; Brosché, Mikael; Böwer, Nathalie; Strid, Hilja; Gittins, John R; Grahn, Elin; Eriksson, Leif A; Strid, Åke

2011-04-01

The pea (Pisum sativum) tetrameric short-chain alcohol dehydrogenase-like protein (SAD) family consists of at least three highly similar members (SAD-A, -B, and -C). According to mRNA data, environmental stimuli induce SAD expression. The aim of this study was to characterize the SAD proteins by examining their catalytic function, distribution in pea, and induction in different tissues. In enzyme activity assays using a range of potential substrates, the SAD-C enzyme was shown to reduce one- or two-ring-membered quinones lacking long hydrophobic hydrocarbon tails. Immunological assays using a specific antiserum against the protein demonstrated that different tissues and cell types contain small amounts of SAD protein that was predominantly located within epidermal or subepidermal cells and around vascular tissue. Particularly high local concentrations were observed in the protoderm of the seed cotyledonary axis. Two bow-shaped rows of cells in the ovary and the placental surface facing the ovule also exhibited considerable SAD staining. Ultraviolet-B irradiation led to increased staining in epidermal and subepidermal cells of leaves and stems. The different localization patterns of SAD suggest functions both in development and in responses to environmental stimuli. Finally, the pea SAD-C promoter was shown to confer heterologous wound-induced expression in Arabidopsis (Arabidopsis thaliana), which confirmed that the inducibility of its expression is regulated at the transcriptional level.

The Pea SAD Short-Chain Dehydrogenase/Reductase: Quinone Reduction, Tissue Distribution, and Heterologous Expression1[W][OA

PubMed Central

Scherbak, Nikolai; Ala-Häivälä, Anneli; Brosché, Mikael; Böwer, Nathalie; Strid, Hilja; Gittins, John R.; Grahn, Elin; Eriksson, Leif A.; Strid, Åke

2011-01-01

The pea (Pisum sativum) tetrameric short-chain alcohol dehydrogenase-like protein (SAD) family consists of at least three highly similar members (SAD-A, -B, and -C). According to mRNA data, environmental stimuli induce SAD expression. The aim of this study was to characterize the SAD proteins by examining their catalytic function, distribution in pea, and induction in different tissues. In enzyme activity assays using a range of potential substrates, the SAD-C enzyme was shown to reduce one- or two-ring-membered quinones lacking long hydrophobic hydrocarbon tails. Immunological assays using a specific antiserum against the protein demonstrated that different tissues and cell types contain small amounts of SAD protein that was predominantly located within epidermal or subepidermal cells and around vascular tissue. Particularly high local concentrations were observed in the protoderm of the seed cotyledonary axis. Two bow-shaped rows of cells in the ovary and the placental surface facing the ovule also exhibited considerable SAD staining. Ultraviolet-B irradiation led to increased staining in epidermal and subepidermal cells of leaves and stems. The different localization patterns of SAD suggest functions both in development and in responses to environmental stimuli. Finally, the pea SAD-C promoter was shown to confer heterologous wound-induced expression in Arabidopsis (Arabidopsis thaliana), which confirmed that the inducibility of its expression is regulated at the transcriptional level. PMID:21343423

Distribution of selenium in zebrafish larvae after exposure to organic and inorganic selenium forms.

PubMed

Dolgova, N V; Hackett, M J; MacDonald, T C; Nehzati, S; James, A K; Krone, P H; George, G N; Pickering, I J

2016-03-01

Selenium is an essential micronutrient for many organisms, and in vertebrates has a variety of roles associated with protection from reactive oxygen species. Over the past two decades there have been conflicting reports upon human health benefits and detriments arising from consumption of selenium dietary supplements. Thus, early studies report a decrease in the incidence of certain types of cancer, whereas subsequent studies did not observe any anti-cancer effect, and adverse effects such as increased risks for type 2 diabetes have been reported. A possible contributing factor may be that different chemical forms of selenium were used in different studies. Using larval stage zebrafish (Danio rerio) as a model organism, we report a comparison of the toxicities and tissue selenium distributions of four different chemical forms of selenium. We find that the organic forms of selenium tested (Se-methyl-l-selenocysteine and l-selenomethionine) show considerably more toxicity than inorganic forms (selenite and selenate), and that this appears to be correlated with the level of bioaccumulation. Despite differences in concentrations, the tissue specific pattern of selenium accumulation was similar for the chemical forms tested; selenium was found to be highly concentrated in pigment (melanin) containing tissues especially for the organic selenium treatments, with lower concentrations in eye lens, yolk sac and heart. These results suggest that pigmented tissues might serve as a storage reservoir for selenium.

Development of maternal seed tissue in barley is mediated by regulated cell expansion and cell disintegration and coordinated with endosperm growth.

PubMed

Radchuk, Volodymyr; Weier, Diana; Radchuk, Ruslana; Weschke, Winfriede; Weber, Hans

2011-01-01

After fertilization, filial grain organs are surrounded by the maternal nucellus embedded within the integuments and pericarp. Rapid early endosperm growth must be coordinated with maternal tissue development. Parameters of maternal tissue growth and development were analysed during early endosperm formation. In the pericarp, cell proliferation is accomplished around the time of fertilization, followed by cell elongation predominantly in longitudinal directions. The rapid cell expansion coincides with endosperm cellularization. Distribution of TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling)-positive nuclei reveals distinct patterns starting in the nucellus at anthesis and followed later by the inner cell rows of the pericarp, then spreading to the whole pericarp. The pattern suggests timely and spatially regulated programmed cell death (PCD) processes in maternal seed tissues. When the endosperm is coenocytic, PCD events are only observed within the nucellus. Thereby, remobilization of nucellar storage compounds by PCD could nourish the early developing endosperm when functional interconnections are absent between maternal and filial seed organs. Specific proteases promote PCD events. Characterization of the barley vacuolar processing enzyme (VPE) gene family identified seven gene members specifically expressed in the developing grain. HvVPE2a (known as nucellain) together with closely similar HvVPE2b and HvVPE2d might be involved in nucellar PCD. HvVPE4 is strongly cell specific for pericarp parenchyma. Correlative evidence suggests that HvVPE4 plays a role in PCD events in the pericarp. Possible functions of PCD in the maternal tissues imply a potential nutritive role or the relief of a physical restraint for endosperm growth. PCD could also activate post-phloem transport functions.

Towards automated early cancer detection: Non-invasive, fluorescence-based approaches for quantitative assessment of cells and tissue to identify pre-cancers

NASA Astrophysics Data System (ADS)

Levitt, Jonathan Michael

Cancer is the second leading cause of death globally, second only to heart disease. As in many diseases, patient survival is directly related to how early lesions are detected. Using conventional screening methods, the early changes associated with cancer, which occur on the microscopic scale, can easily go overlooked. Due to the inherent drawbacks of conventional techniques we present non-invasive, optically based methods to acquire high resolution images from live samples and assess cellular function associated with the onset of disease. Specifically, we acquired fluorescence images from NADH and FAD to quantify morphology and metabolic activity. We first conducted studies to monitor monolayers of keratinocytes in response to apoptosis which has been shown to be disrupted during cancer progression. We found that as keratinocytes undergo apoptosis there are populations of mitochondria that exhibit a higher metabolic activity that become progressively confined to a gradually smaller perinuclear region. To further assess the changes associated with early cancer growth we developed automated methods to rapidly quantify fluorescence images and extract morphological and metabolic information from life tissue. In this study, we simultaneously quantified mitochondrial organization, metabolic activity, nuclear size distribution, and the localization of the structural protein keratin, to differentiate between normal and pre-cancerous engineered tissues. We found the degree mitochondrial organization, as determined from the fractal derived Hurst parameter, was well correlated to level of cellular differentiation. We also found that the metabolic activity in the pre-cancerous cells was greater and more consistent throughout tissue depths in comparison to normal tissue. Keratin localization, also quantified from the fluorescence images, we found it to be confined to the uppermost layers of normal tissue while it was more evenly distributed in the precancerous tissues. To allow for evaluation of the early cancerous changes in vivo, we developed video-rate confocal reflectance/multi-photon fluorescence microscope as a clinical prototype. This device was specifically designed to rapidly acquire and assess non-invasively acquire fluorescence images using the automated methods we have developed. We have demonstrated the ability of this microscope to simultaneously acquire fluorescence, confocal reflectance, and second-harmonic generation images as well as assess blood flow in vivo.

Distribution and expression in vitro and in vivo of DNA vaccine against lymphocystis disease virus in Japanese flounder ( Paralichthys olivaceus)

NASA Astrophysics Data System (ADS)

Zheng, Fengrong; Sun, Xiuqin; Liu, Hongzhan; Wu, Xingan; Zhong, Nan; Wang, Bo; Zhou, Guodong

2010-01-01

Lymphocystis disease, caused by the lymphocystis disease virus (LCDV), is a significant worldwide problem in fish industry causing substantial economic losses. In this study, we aimed to develop the DNA vaccine against LCDV, using DNA vaccination technology. We evaluated plasmid pEGFP-N2-LCDV1.3 kb as a DNA vaccine candidate. The plasmid DNA was transiently expressed after liposome transfection into the eukaryotic COS 7 cell line. The distribution and expression of the DNA vaccine (pEGFP-N2-LCDV1.3kb) were also analyzed in tissues of the vaccinated Japanese flounder by PCR, RT-PCR and fluorescent microscopy. Results from PCR analysis indicated that the vaccine-containing plasmids were distributed in injected muscle, the muscle opposite the injection site, the hind intestine, gill, spleen, head, kidney and liver, 6 and 25 days after vaccination. The vaccine plasmids disappeared 100 d post-vaccination. Fluorescent microscopy revealed green fluorescence in the injected muscle, the muscle opposite the injection site, the hind intestine, gill, spleen, head, kidney and liver of fish 48 h post-vaccination, green fluorescence did not appear in the control treated tissue. Green fluorescence became weak at 60 days post-vaccination. RT-PCR analysis indicated that the mcp gene was expressed in all tested tissues of vaccinated fish 6-50 days post-vaccination. These results demonstrate that the antigen encoded by the DNA vaccine is distributed and expressed in all of the tissues analyzed in the vaccinated fish. The antigen would therefore potentially initiate a specific immune response. the plasmid DNA was injected into Japanese flounder ( Paralichthys olivaceus) intramuscularly and antibodies against LCDV were evaluated. The results indicate that the plasmid encoded DNA vaccine could induce an immune response to LCDV and would therefore offer immune protection against LCD. Further studies are required for the development and application of this promising DNA vaccine.

Adipose tissue content and distribution in children and adolescents with bronchial asthma.

PubMed

Umławska, Wioleta

2015-02-01

The excess of adipose tissue and the pattern of adipose tissue distribution in the body seem to play an important role in the complicated dependencies between obesity and risk of developing asthma. The aim of the present study was to determine nutritional status in children and adolescents with bronchial asthma with special emphasis on adipose tissue distribution evaluated on the basis of skin-fold thicknesses, and to determine the relationships between patterns of adipose tissue distribution and the course of the disease. Anthropometric data on height, weight, circumferences and skin-fold thicknesses were extracted from the medical histories of 261 children diagnosed with asthma bronchitis. Values for children with asthma were compared to Polish national growth reference charts. Distribution of subcutaneous adipose tissue was evaluated using principal components analysis (PCA). Multivariate linear regression analyses tested the effect of three factors on subcutaneous adipose tissue distribution: type of asthma, the severity of the disease and the duration of the disease. Mean body height in the children examined in this study was lower than in their healthy peers. Mean BMI and skin-fold thicknesses were significantly higher and lean body mass was lower in the study group. Excess body fat was noted, especially in girls. Adipose tissue was preferentially deposited in the trunk in girls with severe asthma, as well as in those who had been suffering from asthma for a longer time. The type of asthma, atopic or non-atopic, had no observable effect on subcutaneous adipose tissue distribution in children examined. The data suggest that long-treated subjects and those with severe bronchial asthma accumulate more adipose tissue on the trunk. It is important to regularly monitor nutritional status in children with asthma, especially in those receiving high doses of systemic or inhaled glucocorticosteroids, and long-term treatment as well. Copyright © 2014 Elsevier Ltd. All rights reserved.

Novel green tissue-specific synthetic promoters and cis-regulatory elements in rice.

PubMed

Wang, Rui; Zhu, Menglin; Ye, Rongjian; Liu, Zuoxiong; Zhou, Fei; Chen, Hao; Lin, Yongjun

2015-12-11

As an important part of synthetic biology, synthetic promoter has gradually become a hotspot in current biology. The purposes of the present study were to synthesize green tissue-specific promoters and to discover green tissue-specific cis-elements. We first assembled several regulatory sequences related to tissue-specific expression in different combinations, aiming to obtain novel green tissue-specific synthetic promoters. GUS assays of the transgenic plants indicated 5 synthetic promoters showed green tissue-specific expression patterns and different expression efficiencies in various tissues. Subsequently, we scanned and counted the cis-elements in different tissue-specific promoters based on the plant cis-elements database PLACE and the rice cDNA microarray database CREP for green tissue-specific cis-element discovery, resulting in 10 potential cis-elements. The flanking sequence of one potential core element (GEAT) was predicted by bioinformatics. Then, the combination of GEAT and its flanking sequence was functionally identified with synthetic promoter. GUS assays of the transgenic plants proved its green tissue-specificity. Furthermore, the function of GEAT flanking sequence was analyzed in detail with site-directed mutagenesis. Our study provides an example for the synthesis of rice tissue-specific promoters and develops a feasible method for screening and functional identification of tissue-specific cis-elements with their flanking sequences at the genome-wide level in rice.

ROKU: a novel method for identification of tissue-specific genes.

PubMed

Kadota, Koji; Ye, Jiazhen; Nakai, Yuji; Terada, Tohru; Shimizu, Kentaro

2006-06-12

One of the important goals of microarray research is the identification of genes whose expression is considerably higher or lower in some tissues than in others. We would like to have ways of identifying such tissue-specific genes. We describe a method, ROKU, which selects tissue-specific patterns from gene expression data for many tissues and thousands of genes. ROKU ranks genes according to their overall tissue specificity using Shannon entropy and detects tissues specific to each gene if any exist using an outlier detection method. We evaluated the capacity for the detection of various specific expression patterns using synthetic and real data. We observed that ROKU was superior to a conventional entropy-based method in its ability to rank genes according to overall tissue specificity and to detect genes whose expression pattern are specific only to objective tissues. ROKU is useful for the detection of various tissue-specific expression patterns. The framework is also directly applicable to the selection of diagnostic markers for molecular classification of multiple classes.

Cell-Based Meniscal Repair Using an Aligned Bioactive Nanofibrous Sheath

DTIC Science & Technology

2016-07-01

STATEMENT Approved for Public Release; Distribution Unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT The goal of this proposal is to develop a novel bio ...fibers. Secondly, the NFS will be bio -enhanced by impregnation with an extract derived from decellularized meniscus matrix, which contains molecules and...growth factors specific to this tissue, to increase the formation of fibrocartilage by adult stem cells seeded within the scaffold. This bio

Identification of Carbonic Anhydrase IX as a Novel Target for Endoscopic Molecular Imaging of Human Bladder Cancer.

PubMed

Wang, Jiaqi; Fang, Ruizhe; Wang, Lu; Chen, Guang; Wang, Hongzhi; Wang, Zhichao; Zhao, Danfeng; Pavlov, Valentin N; Kabirov, Ildar; Wang, Ziqi; Guo, Pengyu; Peng, Li; Xu, Wanhai

2018-06-27

Emerging novel optical imaging techniques with cancer-specific molecular imaging agents offer a powerful and promising platform for cancer detection and resection. White-light cystoscopy and random bladder biopsies remain the most appropriate but nonetheless suboptimal diagnostic technique for bladder cancer, which is associated with high morbidity and recurrence. However, white-light cystoscopy has intrinsic shortcomings. Although current optical imaging technologies hold great potential for improved diagnostic accuracy, there are few imaging agents for specific molecular targeting. Carbonic anhydrase IX (CAIX) plays a pivotal role in tumorigenesis and tumor progression with potential value as an imaging target. Here, we investigated the feasibility of CAIX as a target and validated the diagnostic performance and significance of CAIX as an imaging agent. We first analyzed the data from The Cancer Genome Atlas (TCGA). Pairs of samples comprising bladder cancer and adjacent normal tissue were collected. All tissue samples were used for real-time PCR and immunohistochemistry to compare CAIX expression in normal and cancer tissue. Using blue-light cystoscopy, we observed the optical distribution of fluorescently labeled CAIX antibody in freshly excised human bladders and obtained random bladder biopsies to assess sensitivity and specificity. The TCGA data revealed that CAIX expression was significantly higher in bladder cancer specimens than in normal tissue. The outcome was similar in quantitative real-time PCR analysis. In immunohistochemical analysis, bladder cancer specimens classified in four pathological subtypes presented a variety of positive staining intensities, whereas no benign specimens showed CAIX staining. Using blue-light cystoscopy, we distinguished bladder cancers that were mainly papillary, some variants of urothelial carcinoma, and less carcinoma in situ, from benign tissue, despite the presence of suspicious-appearing mucosa. The sensitivity and specificity for CAIX-targeted imaging were 88.00% and 93.75%, respectively. CAIX-targeted molecular imaging could be a feasible and adaptive alternative approach for the accurate diagnosis and complete resection of bladder cancer. © 2018 The Author(s). Published by S. Karger AG, Basel.

Laser induced heat source distribution in bio-tissues

NASA Astrophysics Data System (ADS)

Li, Xiaoxia; Fan, Shifu; Zhao, Youquan

2006-09-01

During numerical simulation of laser and tissue thermal interaction, the light fluence rate distribution should be formularized and constituted to the source term in the heat transfer equation. Usually the solution of light irradiative transport equation is given in extreme conditions such as full absorption (Lambert-Beer Law), full scattering (Lubelka-Munk theory), most scattering (Diffusion Approximation) et al. But in specific conditions, these solutions will induce different errors. The usually used Monte Carlo simulation (MCS) is more universal and exact but has difficulty to deal with dynamic parameter and fast simulation. Its area partition pattern has limits when applying FEM (finite element method) to solve the bio-heat transfer partial differential coefficient equation. Laser heat source plots of above methods showed much difference with MCS. In order to solve this problem, through analyzing different optical actions such as reflection, scattering and absorption on the laser induced heat generation in bio-tissue, a new attempt was made out which combined the modified beam broaden model and the diffusion approximation model. First the scattering coefficient was replaced by reduced scattering coefficient in the beam broaden model, which is more reasonable when scattering was treated as anisotropic scattering. Secondly the attenuation coefficient was replaced by effective attenuation coefficient in scattering dominating turbid bio-tissue. The computation results of the modified method were compared with Monte Carlo simulation and showed the model provided reasonable predictions of heat source term distribution than past methods. Such a research is useful for explaining the physical characteristics of heat source in the heat transfer equation, establishing effective photo-thermal model, and providing theory contrast for related laser medicine experiments.

In vivo determination of steric and electrostatic exclusion of albumin in rat skin and skeletal muscle

PubMed Central

Gyenge, Christina C; Tenstad, Olav; Wiig, Helge

2003-01-01

In order to estimate the magnitude of electrostatic exclusion provided by the fixed negative charges of the skin and muscle interstitia of rat in vivo we measured the distribution volumes of two differently charged albumin probes within these tissues. An implanted osmotic pump was used to reach and maintain a steady-state extracellular concentration of a mixture containing two iodine-labelled probes: a charged-modified human serum albumin, cHSA (i.e. a positive probe, isoelectirc point (pI) = 7.6) and a native human serum albumin, HSA (i.e. a normally charged, negative probe, pI = 5.0). Steady-state tissue concentrations were achieved after intravenous infusion of probes for 5–7 days. At the end of this period the animals were nephrectomized and a bolus of 51Cr-EDTA was administered for estimating the extracellular volume. Plasma volumes were measured as 5-min distribution volume of 125I-HSA in separate experiments. The steady-state interstitial fluid concentrations of all probes were determined using nylon wicks implanted postmortem. Calculations of labelled probes were made for interstitial fluid volumes (Vi), extravascular albumin distribution volumes (Vav,a) and relative interstitial excluded volume fractions (Vex,a/Vi). We found that the positive probe is excluded from a significantly smaller fraction of the interstitium. Specifically, the average relative albumin exclusion fractions obtained were: 16% and 26% in skeletal muscle and 30% and 40% in skin, for cHSA and HSA, respectively. On average, the fixed negative charges of the interstitium are responsible for about 40% of the total albumin exclusion in skeletal muscle and 25% in the whole skin tissue and thus, contribute significantly to volume exclusion in these tissues. PMID:12937287

In vivo determination of steric and electrostatic exclusion of albumin in rat skin and skeletal muscle.

PubMed

Gyenge, Christina C; Tenstad, Olav; Wiig, Helge

2003-11-01

In order to estimate the magnitude of electrostatic exclusion provided by the fixed negative charges of the skin and muscle interstitia of rat in vivo we measured the distribution volumes of two differently charged albumin probes within these tissues. An implanted osmotic pump was used to reach and maintain a steady-state extracellular concentration of a mixture containing two iodine-labelled probes: a charged-modified human serum albumin, cHSA (i.e. a positive probe, isoelectirc point (pI) = 7.6) and a native human serum albumin, HSA (i.e. a normally charged, negative probe, pI = 5.0). Steady-state tissue concentrations were achieved after intravenous infusion of probes for 5-7 days. At the end of this period the animals were nephrectomized and a bolus of 51Cr-EDTA was administered for estimating the extracellular volume. Plasma volumes were measured as 5-min distribution volume of 125I-HSA in separate experiments. The steady-state interstitial fluid concentrations of all probes were determined using nylon wicks implanted postmortem. Calculations of labelled probes were made for interstitial fluid volumes (Vi), extravascular albumin distribution volumes (Vav,a) and relative interstitial excluded volume fractions (Vex,a/Vi). We found that the positive probe is excluded from a significantly smaller fraction of the interstitium. Specifically, the average relative albumin exclusion fractions obtained were: 16% and 26% in skeletal muscle and 30% and 40% in skin, for cHSA and HSA, respectively. On average, the fixed negative charges of the interstitium are responsible for about 40% of the total albumin exclusion in skeletal muscle and 25% in the whole skin tissue and thus, contribute significantly to volume exclusion in these tissues.

Comparative glycan profiling of Ceratopteris richardii 'C-Fern' gametophytes and sporophytes links cell-wall composition to functional specialization.

PubMed

Eeckhout, Sharon; Leroux, Olivier; Willats, William G T; Popper, Zoë A; Viane, Ronald L L

2014-10-01

Innovations in vegetative and reproductive characters were key factors in the evolutionary history of land plants and most of these transformations, including dramatic changes in life cycle structure and strategy, necessarily involved cell-wall modifications. To provide more insight into the role of cell walls in effecting changes in plant structure and function, and in particular their role in the generation of vascularization, an antibody-based approach was implemented to compare the presence and distribution of cell-wall glycan epitopes between (free-living) gametophytes and sporophytes of Ceratopteris richardii 'C-Fern', a widely used model system for ferns. Microarrays of sequential diamino-cyclohexane-tetraacetic acid (CDTA) and NaOH extractions of gametophytes, spores and different organs of 'C-Fern' sporophytes were probed with glycan-directed monoclonal antibodies. The same probes were employed to investigate the tissue- and cell-specific distribution of glycan epitopes. While monoclonal antibodies against pectic homogalacturonan, mannan and xyloglucan widely labelled gametophytic and sporophytic tissues, xylans were only detected in secondary cell walls of the sporophyte. The LM5 pectic galactan epitope was restricted to sporophytic phloem tissue. Rhizoids and root hairs showed similarities in arabinogalactan protein (AGP) and xyloglucan epitope distribution patterns. The differences and similarities in glycan cell-wall composition between 'C-Fern' gametophytes and sporophytes indicate that the molecular design of cell walls reflects functional specialization rather than genetic origin. Glycan epitopes that were not detected in gametophytes were associated with cell walls of specialized tissues in the sporophyte. © The Author 2014. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Plasticity of adipose tissue in response to fasting and refeeding in male mice.

PubMed

Tang, Hao-Neng; Tang, Chen-Yi; Man, Xiao-Fei; Tan, Shu-Wen; Guo, Yue; Tang, Jun; Zhou, Ci-La; Zhou, Hou-De

2017-01-01

Fasting is the most widely prescribed and self-imposed strategy for treating excessive weight gain and obesity, and has been shown to exert a number of beneficial effects. The aim of the present study was to determine the exact role of fasting and subsequent refeeding on fat distribution in mice. C57/BL6 mice fasted for 24 to 72 h and were then subjected to refeeding for 72 h. At 24, 48 and 72 h of fasting, and 12, 24, 48 and 72 h of refeeding, the mice were sacrificed, and serum and various adipose tissues were collected. Serum biochemical parameters, adipose tissue masses and histomorphological analysis of different depots were detected. MRNA was isolated from various adipose tissues, and the expressions of thermogenesis, visceral signature and lipid metabolism-related genes were examined. The phenotypes of adipose tissues between juvenile and adult mice subjected to fasting and refeeding were also compared. Fasting preferentially consumed mesenteric fat mass and decreased the cell size of mesenteric depots; however, refeeding recovered the mass and morphology of inguinal adipose tissues preferentially compared with visceral depots. Thermogenesis-related gene expression in the inguinal WAT and interscapular BAT were suppressed. Mitochondrial biogenesis was affected by fasting in a depot-specific manner. Furthermore, a short period of fasting led to an increase in visceral signature genes ( Wt1, Tcf21 ) in subcutaneous adipose tissue, while the expression of these genes decreased sharply as the fasting time increased. Additionally, lipogenesis-related markers were enhanced to a greater extent greater in subcutaneous depots compared with those in visceral adipose tissues by refeeding. Although similar phenotypic changes in adipose tissue were observed between juvenile mice and adult mice subjected to fasting and refeeding, the alterations appeared earlier and more sensitively in juvenile mice. Fasting preferentially consumes lipids in visceral adipose tissues, whereas refeeding recovers lipids predominantly in subcutaneous adipose tissues, which indicated the significance of plasticity of adipose organs for fat distribution when subject to food deprivation or refeeding.

Distribution, metabolism and excretion of a synthetic androgen 7alpha-methyl-19-nortestosterone, a potential male-contraceptive.

PubMed

Prasad, Pramod Vishwanath; Arumugam, Ramamani; Willman, Mark; Ge, Ren-Shan; Sitruk-Ware, Regine; Kumar, Narender

2009-01-01

A synthetic androgen 7alpha-Methyl-19-nortestosterone (MENT) has a potential for therapeutic use in 'androgen replacement therapy' for hypogonadal men or as a hormonal male-contraceptive in normal men. Its tissue distribution, excretion and metabolic enzyme(s) have not been reported. Therefore, the present study tested the distribution and excretion of MENT in Sprague-Dawley rats castrated 24h prior to the injection of tritium-labeled MENT ((3)H-MENT). Rats were euthanized at different time intervals after dosing, and the amount of radioactivity in various tissues/organs was measured following combustion in a Packard oxidizer. The radioactivity (% injected dose) was highest in the duodenal contents in the first 30min of injection. Specific uptake of the steroid was observed in target tissues such as ventral prostate and seminal vesicles at 6h, while in other tissues radioactivity equilibrated with blood. Liver and duodenum maintained high radioactivity throughout, as these organs were actively involved in the metabolism and excretion of most drugs. The excretion of (3)H-MENT was investigated after subcutaneous injection of (3)H-MENT into male rats housed in metabolic cages. Urine and feces were collected at different time intervals (up to 72h) following injection. Results showed that the radioactivity was excreted via feces and urine in equal amounts by 30h. Aiming to identify enzyme(s) involved in the MENT metabolism, we performed in vitro metabolism of (3)H-MENT using rat and human liver microsomes, cytosol and recombinant cytochrome P(450) (CYP) isozymes. The metabolites were separated by thin-layer chromatography (TLC). Three putative metabolites (in accordance with the report of Agarwal and Monder [Agarwal AK, Monder C. In vitro metabolism of 7alpha-methyl-19-nortestosterone by rat liver, prostate, and epididymis. Endocrinology 1988;123:2187-93]), [i] 3-hydroxylated MENT by both rat and human liver cytosol; [ii] 16alpha-hydroxylated MENT (a polar metabolite) by both rat and human hepatic microsomes; and [iii] 7alpha-methyl-19-norandrostenedione (a non-polar metabolite) by human hepatic microsomes, were obtained. By employing chemical inhibitors and specific anti-CYP antibodies, (3)H-MENT was found to be metabolized specifically by rat CYP 2C11 and 3-hydroxysteroid dehydrogenase (3-HSD) enzymes whereas in humans it was accomplished by CYP 3A4, 17beta-hydroxysteroid dehydrogenase (17beta-HSD) and 3-HSD enzymes.

A mechano-biological model of multi-tissue evolution in bone

NASA Astrophysics Data System (ADS)

Frame, Jamie; Rohan, Pierre-Yves; Corté, Laurent; Allena, Rachele

2017-12-01

Successfully simulating tissue evolution in bone is of significant importance in predicting various biological processes such as bone remodeling, fracture healing and osseointegration of implants. Each of these processes involves in different ways the permanent or transient formation of different tissue types, namely bone, cartilage and fibrous tissues. The tissue evolution in specific circumstances such as bone remodeling and fracturing healing is currently able to be modeled. Nevertheless, it remains challenging to predict which tissue types and organization can develop without any a priori assumptions. In particular, the role of mechano-biological coupling in this selective tissue evolution has not been clearly elucidated. In this work, a multi-tissue model has been created which simultaneously describes the evolution of bone, cartilage and fibrous tissues. The coupling of the biological and mechanical factors involved in tissue formation has been modeled by defining two different tissue states: an immature state corresponding to the early stages of tissue growth and representing cell clusters in a weakly neo-formed Extra Cellular Matrix (ECM), and a mature state corresponding to well-formed connective tissues. This has allowed for the cellular processes of migration, proliferation and apoptosis to be described simultaneously with the changing ECM properties through strain driven diffusion, growth, maturation and resorption terms. A series of finite element simulations were carried out on idealized cantilever bending geometries. Starting from a tissue composition replicating a mid-diaphysis section of a long bone, a steady-state tissue formation was reached over a statically loaded period of 10,000 h (60 weeks). The results demonstrated that bone formation occurred in regions which are optimally physiologically strained. In two additional 1000 h bending simulations both cartilaginous and fibrous tissues were shown to form under specific geometrical and loading cases and cartilage was shown to lead to the formation of bone in a beam replicating a fracture healing initial tissue distribution. This finding is encouraging in that it is corroborated by similar experimental observations of cartilage leading bone formation during the fracture healing process. The results of this work demonstrate that a multi-tissue mechano-biological model of tissue evolution has the potential for predictive analysis in the design and implementations of implants, describing fracture healing and bone remodeling processes.

Fluorescence labeling of carbonylated lipids and proteins in cells using coumarin-hydrazide

PubMed Central

Vemula, Venukumar; Ni, Zhixu; Fedorova, Maria

2015-01-01

Carbonylation is a generic term which refers to reactive carbonyl groups present in biomolecules due to oxidative reactions induced by reactive oxygen species. Carbonylated proteins, lipids and nucleic acids have been intensively studied and often associated with onset or progression of oxidative stress related disorders. In order to reveal underlying carbonylation pathways and biological relevance, it is crucial to study their intracellular formation and spatial distribution. Carbonylated species are usually identified and quantified in cell lysates and body fluids after derivatization using specific chemical probes. However, spatial cellular and tissue distribution have been less often investigated. Here, we report coumarin-hydrazide, a fluorescent chemical probe for time- and cost-efficient labeling of cellular carbonyls followed by fluorescence microscopy to evaluate their intracellular formation both in time and space. The specificity of coumarin-hydrazide was confirmed in time- and dose-dependent experiments using human primary fibroblasts stressed with paraquat and compared with conventional DNPH-based immunocytochemistry. Both techniques stained carbonylated species accumulated in cytoplasm with strong perinuclear clustering. Using a complimentary array of analytical methods specificity of coumarin-hydrazide probe towards both protein- and lipid-bound carbonyls has been shown. Additionally, co-distribution of carbonylated species and oxidized phospholipids was demonstrated. PMID:25974625

Characterizing optical properties and spatial heterogeneity of human ovarian tissue using spatial frequency domain imaging

NASA Astrophysics Data System (ADS)

Nandy, Sreyankar; Mostafa, Atahar; Kumavor, Patrick D.; Sanders, Melinda; Brewer, Molly; Zhu, Quing

2016-10-01

A spatial frequency domain imaging (SFDI) system was developed for characterizing ex vivo human ovarian tissue using wide-field absorption and scattering properties and their spatial heterogeneities. Based on the observed differences between absorption and scattering images of different ovarian tissue groups, six parameters were quantitatively extracted. These are the mean absorption and scattering, spatial heterogeneities of both absorption and scattering maps measured by a standard deviation, and a fitting error of a Gaussian model fitted to normalized mean Radon transform of the absorption and scattering maps. A logistic regression model was used for classification of malignant and normal ovarian tissues. A sensitivity of 95%, specificity of 100%, and area under the curve of 0.98 were obtained using six parameters extracted from the SFDI images. The preliminary results demonstrate the diagnostic potential of the SFDI method for quantitative characterization of wide-field optical properties and the spatial distribution heterogeneity of human ovarian tissue. SFDI could be an extremely robust and valuable tool for evaluation of the ovary and detection of neoplastic changes of ovarian cancer.

The Fluorescent Antibody Technique in the Diagnosis of Equine Rhinopneumonitis Virus Abortion

PubMed Central

Smith, I. M.; Girard, A.; Corner, A. H.; Mitchell, D.

1972-01-01

Using two known positive equine viral rhinopneumonitis (EVR) sera, conjugates were prepared with fluorescein isothiocyanate and tested for specificity using EVR infected tissue culture cells. The conjugate was then applied to selected tissues from 32 aborted fetuses and foals submitted during a natural outbreak of EVR. Antigen was detected in various tissues by immunofluorescence in 20 cases (62.5%). In 24 cases bovine fetal kidney cell monolayers were inoculated with a pool of lung and liver and EVR virus was isolated from 15 (62.5%). Histological examination of various tissues from 29 cases resulted in the diagnosis of EVR in 19 (65.5%), based upon the presence of focal areas of necrosis and intranuclear inclusion bodies. Correlation of results was not obtained in two cases. One was diagnosed positive histologically and negative on fluorescence, the other was negative histologically and by virus isolation but showed fluorescence. The distribution of fluorescence in various infected fetal tissues indicated that the combined examination of lung and thymus gland was most likely to provide a positive diagnosis. ImagesFig. 1.Fig. 2. PMID:4114979

SH2 Domain Histochemistry.

PubMed

Buhs, Sophia; Nollau, Peter

2017-01-01

Among posttranslational modifications, the phosphorylation of tyrosine residues is a key modification in cell signaling. Because of its biological importance, characterization of the cellular state of tyrosine phosphorylation is of great interest. Based on the unique properties of endogenously expressed SH2 domains recognizing tyrosine phosphorylated signaling proteins with high specificity we have developed an alternative approach, coined SH2 profiling, enabling us to decipher complex patterns of tyrosine phosphorylation in various normal and cancerous tissues. So far, SH2 profiling has largely been applied for the analysis of protein extracts with the limitation that information on spatial distribution and intensity of tyrosine phosphorylation within a tissue is lost. Here, we describe a novel SH2 domain based strategy for differential characterization of the state of tyrosine phosphorylation in formaldehyde-fixed and paraffin-embedded tissues. This approach demonstrates that SH2 domains may serve as very valuable tools for the analysis of the differential state of tyrosine phosphorylation in primary tissues fixed and processed under conditions frequently applied by routine pathology laboratories.

Bioprinting of Cartilage and Skin Tissue Analogs Utilizing a Novel Passive Mixing Unit Technique for Bioink Precellularization

PubMed Central

Thayer, Patrick Scott; Orrhult, Linnea Stridh; Martínez, Héctor

2018-01-01

Bioprinting is a powerful technique for the rapid and reproducible fabrication of constructs for tissue engineering applications. In this study, both cartilage and skin analogs were fabricated after bioink pre-cellularization utilizing a novel passive mixing unit technique. This technique was developed with the aim to simplify the steps involved in the mixing of a cell suspension into a highly viscous bioink. The resolution of filaments deposited through bioprinting necessitates the assurance of uniformity in cell distribution prior to printing to avoid the deposition of regions without cells or retention of large cell clumps that can clog the needle. We demonstrate the ability to rapidly blend a cell suspension with a bioink prior to bioprinting of both cartilage and skin analogs. Both tissue analogs could be cultured for up to 4 weeks. Histological analysis demonstrated both cell viability and deposition of tissue specific extracellular matrix (ECM) markers such as glycosaminoglycans (GAGs) and collagen I respectively. PMID:29364216

Insight into plant cell wall chemistry and structure by combination of multiphoton microscopy with Raman imaging.

PubMed

Heiner, Zsuzsanna; Zeise, Ingrid; Elbaum, Rivka; Kneipp, Janina

2018-04-01

Spontaneous Raman scattering microspectroscopy, second harmonic generation (SHG) and 2-photon excited fluorescence (2PF) were used in combination to characterize the morphology together with the chemical composition of the cell wall in native plant tissues. As the data obtained with unstained sections of Sorghum bicolor root and leaf tissues illustrate, nonresonant as well as pre-resonant Raman microscopy in combination with hyperspectral analysis reveals details about the distribution and composition of the major cell wall constituents. Multivariate analysis of the Raman data allows separation of different tissue regions, specifically the endodermis, xylem and lumen. The orientation of cellulose microfibrils is obtained from polarization-resolved SHG signals. Furthermore, 2-photon autofluorescence images can be used to image lignification. The combined compositional, morphological and orientational information in the proposed coupling of SHG, Raman imaging and 2PF presents an extension of existing vibrational microspectroscopic imaging and multiphoton microscopic approaches not only for plant tissues. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Perfluorooctane Sulfonate Plasma Half-Life Determination and Long-Term Tissue Distribution in Beef Cattle (Bos taurus).

PubMed

Lupton, Sara J; Dearfield, Kerry L; Johnston, John J; Wagner, Sarah; Huwe, Janice K

2015-12-30

Perfluorooctane sulfonate (PFOS) is used in consumer products as a surfactant and is found in industrial and consumer waste, which ends up in wastewater treatment plants (WWTPs). PFOS does not breakdown during WWTP processes and accumulates in the biosolids. Common practices include application of biosolids to pastures and croplands used for feed, and as a result, animals such as beef cattle are exposed to PFOS. To determine plasma and tissue depletion kinetics in cattle, 2 steers and 4 heifers were dosed with PFOS at 0.098 mg/kg body weight and 9.1 mg/kg, respectively. Plasma depletion half-lives for steers and heifers were 120 ± 4.1 and 106 ± 23.1 days, respectively. Specific tissue depletion half-lives ranged from 36 to 385 days for intraperitoneal fat, back fat, muscle, liver, bone, and kidney. These data indicate that PFOS in beef cattle has a sufficiently long depletion half-life to permit accumulation in edible tissues.

Identification of tissue-specific targeting peptide

NASA Astrophysics Data System (ADS)

Jung, Eunkyoung; Lee, Nam Kyung; Kang, Sang-Kee; Choi, Seung-Hoon; Kim, Daejin; Park, Kisoo; Choi, Kihang; Choi, Yun-Jaie; Jung, Dong Hyun

2012-11-01

Using phage display technique, we identified tissue-targeting peptide sets that recognize specific tissues (bone-marrow dendritic cell, kidney, liver, lung, spleen and visceral adipose tissue). In order to rapidly evaluate tissue-specific targeting peptides, we performed machine learning studies for predicting the tissue-specific targeting activity of peptides on the basis of peptide sequence information using four machine learning models and isolated the groups of peptides capable of mediating selective targeting to specific tissues. As a representative liver-specific targeting sequence, the peptide "DKNLQLH" was selected by the sequence similarity analysis. This peptide has a high degree of homology with protein ligands which can interact with corresponding membrane counterparts. We anticipate that our models will be applicable to the prediction of tissue-specific targeting peptides which can recognize the endothelial markers of target tissues.

On the effects of alternative optima in context-specific metabolic model predictions

PubMed Central

Nikoloski, Zoran

2017-01-01

The integration of experimental data into genome-scale metabolic models can greatly improve flux predictions. This is achieved by restricting predictions to a more realistic context-specific domain, like a particular cell or tissue type. Several computational approaches to integrate data have been proposed—generally obtaining context-specific (sub)models or flux distributions. However, these approaches may lead to a multitude of equally valid but potentially different models or flux distributions, due to possible alternative optima in the underlying optimization problems. Although this issue introduces ambiguity in context-specific predictions, it has not been generally recognized, especially in the case of model reconstructions. In this study, we analyze the impact of alternative optima in four state-of-the-art context-specific data integration approaches, providing both flux distributions and/or metabolic models. To this end, we present three computational methods and apply them to two particular case studies: leaf-specific predictions from the integration of gene expression data in a metabolic model of Arabidopsis thaliana, and liver-specific reconstructions derived from a human model with various experimental data sources. The application of these methods allows us to obtain the following results: (i) we sample the space of alternative flux distributions in the leaf- and the liver-specific case and quantify the ambiguity of the predictions. In addition, we show how the inclusion of ℓ1-regularization during data integration reduces the ambiguity in both cases. (ii) We generate sets of alternative leaf- and liver-specific models that are optimal to each one of the evaluated model reconstruction approaches. We demonstrate that alternative models of the same context contain a marked fraction of disparate reactions. Further, we show that a careful balance between model sparsity and metabolic functionality helps in reducing the discrepancies between alternative models. Finally, our findings indicate that alternative optima must be taken into account for rendering the context-specific metabolic model predictions less ambiguous. PMID:28557990

On the effects of alternative optima in context-specific metabolic model predictions.

PubMed

Robaina-Estévez, Semidán; Nikoloski, Zoran

2017-05-01

The integration of experimental data into genome-scale metabolic models can greatly improve flux predictions. This is achieved by restricting predictions to a more realistic context-specific domain, like a particular cell or tissue type. Several computational approaches to integrate data have been proposed-generally obtaining context-specific (sub)models or flux distributions. However, these approaches may lead to a multitude of equally valid but potentially different models or flux distributions, due to possible alternative optima in the underlying optimization problems. Although this issue introduces ambiguity in context-specific predictions, it has not been generally recognized, especially in the case of model reconstructions. In this study, we analyze the impact of alternative optima in four state-of-the-art context-specific data integration approaches, providing both flux distributions and/or metabolic models. To this end, we present three computational methods and apply them to two particular case studies: leaf-specific predictions from the integration of gene expression data in a metabolic model of Arabidopsis thaliana, and liver-specific reconstructions derived from a human model with various experimental data sources. The application of these methods allows us to obtain the following results: (i) we sample the space of alternative flux distributions in the leaf- and the liver-specific case and quantify the ambiguity of the predictions. In addition, we show how the inclusion of ℓ1-regularization during data integration reduces the ambiguity in both cases. (ii) We generate sets of alternative leaf- and liver-specific models that are optimal to each one of the evaluated model reconstruction approaches. We demonstrate that alternative models of the same context contain a marked fraction of disparate reactions. Further, we show that a careful balance between model sparsity and metabolic functionality helps in reducing the discrepancies between alternative models. Finally, our findings indicate that alternative optima must be taken into account for rendering the context-specific metabolic model predictions less ambiguous.

LASER BIOLOGY: Visualisation of the distributions of melanin and indocyanine green in biological tissues

NASA Astrophysics Data System (ADS)

Genina, E. A.; Fedosov, I. V.; Bashkatov, A. N.; Zimnyakov, D. A.; Altshuler, G. B.; Tuchin, V. V.

2008-03-01

A double-wavelength laser scanning microphotometer with the high spectral and spatial resolutions is developed for studying the distribution of endogenic and exogenic dyes in biological tissues. Samples of hair and skin biopsy with hair follicles stained with indocyanine green are studied. The spatial distribution of indocyanine green and melanin in the biological tissue is determined from the measured optical transmittance.

Visualisation of the distributions of melanin and indocyanine green in biological tissues

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

Genina, E A; Fedosov, I V; Bashkatov, A N

2008-03-31

A double-wavelength laser scanning microphotometer with the high spectral and spatial resolutions is developed for studying the distribution of endogenic and exogenic dyes in biological tissues. Samples of hair and skin biopsy with hair follicles stained with indocyanine green are studied. The spatial distribution of indocyanine green and melanin in the biological tissue is determined from the measured optical transmittance. (laser biology)

Multiple roles of phosphoinositide-specific phospholipase C isozymes.

PubMed

Suh, Pann-Ghill; Park, Jae-Il; Manzoli, Lucia; Cocco, Lucio; Peak, Joanna C; Katan, Matilda; Fukami, Kiyoko; Kataoka, Tohru; Yun, Sanguk; Ryu, Sung Ho

2008-06-30

Phosphoinositide-specific phospholipase C is an effector molecule in the signal transduction process. It generates two second messengers, inositol-1,4,5-trisphosphate and diacylglycerol from phosphatidylinositol 4,5-bisphosphate. Currently, thirteen mammal PLC isozymes have been identified, and they are divided into six groups: PLC-beta, -gamma, -delta, -epsilon, -zeta and -eta. Sequence analysis studies demonstrated that each isozyme has more than one alternative splicing variant. PLC isozymes contain the X and Y domains that are responsible for catalytic activity. Several other domains including the PH domain, the C2 domain and EF hand motifs are involved in various biological functions of PLC isozymes as signaling proteins. The distribution of PLC isozymes is tissue and organ specific. Recent studies on isolated cells and knockout mice depleted of PLC isozymes have revealed their distinct phenotypes. Given the specificity in distribution and cellular localization, it is clear that each PLC isozyme bears a unique function in the modulation of physiological responses. In this review, we discuss the structural organization, enzymatic properties and molecular diversity of PLC splicing variants and study functional and physiological roles of each isozyme.

Genotyping of Endosperms to Determine Seed Dormancy Genes Regulating Germination Through Embryonic, Endospermic, or Maternal Tissues in Rice

PubMed Central

Gu, Xing-You; Zhang, Jinfeng; Ye, Heng; Zhang, Lihua; Feng, Jiuhuan

2014-01-01

Seed dormancy is imposed by one or more of the embryo, endosperm, and maternal tissues that belong to two generations and represent two ploidy levels. Many quantitative trait loci (QTL) have been identified for seed dormancy as measured by gross effects on reduced germination rate or delayed germination in crop or model plants. This research developed an endosperm genotype−based genetic approach to determine specific tissues through which a mapped QTL regulates germination using rice as a model. This approach involves testing germination velocity for partially after-ripened seeds harvested from single plants heterozygous for a tested QTL and genotyping endosperms from individual germinated and nongerminated seeds with a codominant DNA marker located on the QTL peak region. Information collected about the QTL includes genotypic frequencies in germinated and/or nongerminated subpopulations; allelic frequency distributions during a germination period; endosperm or embryo genotypic differences in germination velocity; and genotypic frequencies for gametes involved in the double fertilization to form the sampled seeds. Using this approach, the seed dormancy loci SD12, SD1-2, and SD7-1 were determined to regulate germination through the embryo, endosperm, and maternal tissues, respectively; SD12 and SD1-2 acted additively on germination velocity in the offspring tissues; and SD12 also was associated with the preferential fertilization of male gametes in rice. This new genetic approach can be used to characterize mapped genes/QTL for tissue-specific functions in endospermic seeds and for marker-assisted selection of QTL alleles before or immediately after germination in crop breeding. PMID:25480961

Preclinical Pharmacokinetics, Tissue Distribution, and Plasma Protein Binding of Sodium (±)-5-Bromo-2-(α-Hydroxypentyl) Benzoate (BZP), an Innovative Potent Anti-ischemic Stroke Agent.

PubMed

Tian, Xin; Li, Hong-Meng; Wei, Jing-Yao; Liu, Bing-Jie; Zhang, Yu-Hai; Wang, Gao-Ju; Chang, Jun-Biao; Qiao, Hai-Ling

2016-01-01

Sodium (±)-5-bromo-2-(α-hydroxypentyl) benzoate (BZP) is a potential cardiovascular drug and exerts potent neuroprotective effect against transient and long-term ischemic stroke in rats. BZP could convert into 3-butyl-6-bromo-1(3H)-isobenzofuranone (Br-NBP) in vitro and in vivo. However, the pharmacokinetic profiles of BZP and Br-NBP still have not been evaluated. For the purpose of investigating the pharmacokinetic profiles, tissue distribution, and plasma protein binding of BZP and Br-NBP, a rapid, sensitive, and specific method based on liquid chromatography coupled to mass spectrometry (LC-MS/MS) has been developed for determination of BZP and Br-NBP in biological samples. The results indicated that BZP and Br-NBP showed a short elimination half-life, and pharmacokinetic profile in rats (3, 6, and 12 mg/kg; i.v.) and beagle dogs (1, 2, and 4 mg/kg; i.v.gtt) were obtained after single dosing of BZP. After multiple dosing of BZP, there was no significant accumulation of BZP and Br-NBP in the plasma of rats and beagle dogs. Following i.v. single dose (6 mg/kg) of BZP to rats, BZP and Br-NBP were distributed rapidly into all tissues examined, with the highest concentrations of BZP and Br-NBP in lung and kidney, respectively. The brain distribution of Br-NBP in middle cerebral artery occlusion (MCAO) rats was more than in normal rats (P < 0.05). The plasma protein binding degree of BZP at three concentrations (8000, 20,000, and 80,000 ng/mL) from rat, beagle dog, and human plasma were 98.1-98.7, 88.9-92.7, and 74.8-83.7% respectively. In conclusion, both BZP and Br-NBP showed short half-life, good dose-linear pharmacokinetic profile, wide tissue distribution, and different degree protein binding to various species plasma. This was the first preclinical pharmacokinetic investigation of BZP and Br-NBP in both rats and beagle dogs, which provided vital guidance for further preclinical research and the subsequent clinical trials.

A DTU-dependent blood parasitism and a DTU-independent tissue parasitism during mixed infection of Trypanosoma cruzi in immunosuppressed mice.

PubMed

Sales-Campos, Helioswilton; Kappel, Henrique Borges; Andrade, Cristiane Pontes; Lima, Tiago Pereira; Mattos, Mardén Estevão; de Castilho, Alessandra; Correia, Dalmo; Giraldo, Luis Eduardo Ramirez; Lages-Silva, Eliane

2014-01-01

Trypanosoma cruzi (Tc) diversity is determined by different biological, genetic, and biochemical markers and has been grouped into six discrete typing units (DTUs) or taxonomic groups (TcI-TcVI). This variability, coupled with natural reinfection or the hosts' immunosuppression, may play an important role in the pathogenesis of Chagas disease. Therefore, we evaluated the blood and tissue parasitism and genetic profile of mice coinfected with the TcII (JG) strain and TcI AQ1-7 (AQ) or MUTUM (MT) strains during the acute and chronic phases of the disease and during immunosuppression. T. cruzi blood populations in mixed infections were clearly associated with the TcII strain during acute and chronic phases or during immunosuppression. However, in tissues, the parasite populations were distributed according to the strain and the stage of infection. TcII populations overlapped TcI strains during the acute phase; in contrast, during chronic phase, both TcI strains were more prevalent than the TcII strain. The immunosuppression induced selective exacerbation of parasite populations, leading to reactivation of the TcII strain when associated with the AQ, but not with MT strain. Thus, a differential distribution of T. cruzi populations in blood and tissues with overlapping according to the stage of infection and strain used was observed. Blood parasitism was associated with the DTU TcII and tissue parasitism with a specific parasite strain and not with DTUs. Finally, to our knowledge, this is the first study to analyze subpatent blood parasitism and to simultaneously identify different T. cruzi populations in tissues and blood.

Development of a Tissue-Mimicking Phantom for Evaluating the Focusing Performance of High Intensity Focused Ultrasound

NASA Astrophysics Data System (ADS)

Zongyu, Jing; Faqi, Li; Jiangzhong, Zou; Zhibiao, Wang

2006-05-01

Objectives: To develop a tissue mimicking phantom which can be used to evaluate the focusing performance of the HIFU transducer, and the phantom should has the same acoustic characteristic and thermotics characteristic as the biological tissue. Materials and methods: The tissue mimicking phantom was made from water, gelatin, fresh biologic tissue Its ultrasonic parameters (attenuation coefficient) of the phantom was measured by the method of radiation pressure, and thermotics parameters of the phantom, including thermal conductivity, specific heat/fusion point et al were tested under the Measurement meter. The HIFU biological effect of the phantom was evaluated under the Model JC focused ultrasound tumor therapeutic system, developed and produced by Chongqing HIFU Technology Co. Ltd (working frequency: 0.7MHz; acoustic power: 200W; focal distance: 135mm; Acoustic focal region: 3×3×25 cubic mm). Results: The self-made phantom is sable, has smooth and glossy appearance, well-distributed construction, and good elasticity. We measured the followed values for acoustic and thermal properties: density 1049±2 kg/m3; attenuation 0.532±0.017 dB/cm (0.8 MHz), 0.612±0.021 dB/cm (1.0 MHz); thermal conductivity 0.76±0.08 W/m/-°C; specific heat 3653±143 J/kg-°C; fusion point154±8°C. The BFR induced in the phantom after HIFU exposure was stable in its size and appearance. Conclusion: We produced and improved one tissue mimicking phantom successfully which had semblable ultrasound and thermphysical properties like the soft tissue, and can replace the bovine liver to investigate the HIFU biological effect and to detect the focusing performance of the HIFU energy transducer. The research was supported by Chongqing University of Medical Science (CX200320).

An image-based skeletal dosimetry model for the ICRP reference newborn—internal electron sources

NASA Astrophysics Data System (ADS)

Pafundi, Deanna; Rajon, Didier; Jokisch, Derek; Lee, Choonsik; Bolch, Wesley

2010-04-01

In this study, a comprehensive electron dosimetry model of newborn skeletal tissues is presented. The model is constructed using the University of Florida newborn hybrid phantom of Lee et al (2007 Phys. Med. Biol. 52 3309-33), the newborn skeletal tissue model of Pafundi et al (2009 Phys. Med. Biol. 54 4497-531) and the EGSnrc-based Paired Image Radiation Transport code of Shah et al (2005 J. Nucl. Med. 46 344-53). Target tissues include the active bone marrow (surrogate tissue for hematopoietic stem cells), shallow marrow (surrogate tissue for osteoprogenitor cells) and unossified cartilage (surrogate tissue for chondrocytes). Monoenergetic electron emissions are considered over the energy range 1 keV to 10 MeV for the following source tissues: active marrow, trabecular bone (surfaces and volumes), cortical bone (surfaces and volumes) and cartilage. Transport results are reported as specific absorbed fractions according to the MIRD schema and are given as skeletal-averaged values in the paper with bone-specific values reported in both tabular and graphic format as electronic annexes (supplementary data). The method utilized in this work uniquely includes (1) explicit accounting for the finite size and shape of newborn ossification centers (spongiosa regions), (2) explicit accounting for active and shallow marrow dose from electron emissions in cortical bone as well as sites of unossified cartilage, (3) proper accounting of the distribution of trabecular and cortical volumes and surfaces in the newborn skeleton when considering mineral bone sources and (4) explicit consideration of the marrow cellularity changes for active marrow self-irradiation as applicable to radionuclide therapy of diseased marrow in the newborn child.

Application of single- and dual-energy CT brain tissue segmentation to PET monitoring of proton therapy

NASA Astrophysics Data System (ADS)

Berndt, Bianca; Landry, Guillaume; Schwarz, Florian; Tessonnier, Thomas; Kamp, Florian; Dedes, George; Thieke, Christian; Würl, Matthias; Kurz, Christopher; Ganswindt, Ute; Verhaegen, Frank; Debus, Jürgen; Belka, Claus; Sommer, Wieland; Reiser, Maximilian; Bauer, Julia; Parodi, Katia

2017-03-01

The purpose of this work was to evaluate the ability of single and dual energy computed tomography (SECT, DECT) to estimate tissue composition and density for usage in Monte Carlo (MC) simulations of irradiation induced β + activity distributions. This was done to assess the impact on positron emission tomography (PET) range verification in proton therapy. A DECT-based brain tissue segmentation method was developed for white matter (WM), grey matter (GM) and cerebrospinal fluid (CSF). The elemental composition of reference tissues was assigned to closest CT numbers in DECT space (DECTdist). The method was also applied to SECT data (SECTdist). In a validation experiment, the proton irradiation induced PET activity of three brain equivalent solutions (BES) was compared to simulations based on different tissue segmentations. Five patients scanned with a dual source DECT scanner were analyzed to compare the different segmentation methods. A single magnetic resonance (MR) scan was used for comparison with an established segmentation toolkit. Additionally, one patient with SECT and post-treatment PET scans was investigated. For BES, DECTdist and SECTdist reduced differences to the reference simulation by up to 62% when compared to the conventional stoichiometric segmentation (SECTSchneider). In comparison to MR brain segmentation, Dice similarity coefficients for WM, GM and CSF were 0.61, 0.67 and 0.66 for DECTdist and 0.54, 0.41 and 0.66 for SECTdist. MC simulations of PET treatment verification in patients showed important differences between DECTdist/SECTdist and SECTSchneider for patients with large CSF areas within the treatment field but not in WM and GM. Differences could be misinterpreted as PET derived range shifts of up to 4 mm. DECTdist and SECTdist yielded comparable activity distributions, and comparison of SECTdist to a measured patient PET scan showed improved agreement when compared to SECTSchneider. The agreement between predicted and measured PET activity distributions was improved by employing a brain specific segmentation applicable to both DECT and SECT data.

C14 Assays and Autoradiographic Studies on the Rooster Comb

PubMed Central

Balazs, Endre A.; Szirmai, John A.; Bergendahl, Gudrun

1959-01-01

The distribution of C14 was studied in various parts of the rooster comb following treatment with testosterone. The value of gas-phase assay of C14 in tissue has been demonstrated and the results compared with those of autoradiographic studies on the same tissue. The results of these experiments showed that androgen treatment significantly increases the rate of incorporation of C14 in various parts of the comb. The specific activity of carbon in the comb, cornea, and liver differed, depending on which precursor, viz. glucose-6-C14, glucose-1-C14, and glucuronolactone-U-C14, was administered. The highest values were obtained after the administration of glucose-6-C14; glucuronolactone-U-C14 gave the lowest specific activity. The specific activity of carbon in different parts of the comb showed considerable variation. Carbon assay of serial sections of the comb cut at various planes showed that the specific activity of carbon was highest in the mucoid layer. Both C14 assays and autoradiograms indicate that C14 is also present in other parts of the comb. As seen in autoradiography, the concentration of C14 was highest in the epithelium, in the blood vessel walls, and in the avascular collagenous tissue. These results, and indications from previous studies, suggest that the high specific activity of carbon in the mucoid layer is due mainly to the presence of C14-labelled hyaluronic acid. Autoradiograms and PAS staining suggest that a significant amount of C14 is also incorporated into the glycoproteins associated with the collagen fibers. PMID:13654453

Identification of Novel Tissue-Specific Genes by Analysis of Microarray Databases: A Human and Mouse Model

PubMed Central

Suh, Yeunsu; Davis, Michael E.; Lee, Kichoon

2013-01-01

Understanding the tissue-specific pattern of gene expression is critical in elucidating the molecular mechanisms of tissue development, gene function, and transcriptional regulations of biological processes. Although tissue-specific gene expression information is available in several databases, follow-up strategies to integrate and use these data are limited. The objective of the current study was to identify and evaluate novel tissue-specific genes in human and mouse tissues by performing comparative microarray database analysis and semi-quantitative PCR analysis. We developed a powerful approach to predict tissue-specific genes by analyzing existing microarray data from the NCBI′s Gene Expression Omnibus (GEO) public repository. We investigated and confirmed tissue-specific gene expression in the human and mouse kidney, liver, lung, heart, muscle, and adipose tissue. Applying our novel comparative microarray approach, we confirmed 10 kidney, 11 liver, 11 lung, 11 heart, 8 muscle, and 8 adipose specific genes. The accuracy of this approach was further verified by employing semi-quantitative PCR reaction and by searching for gene function information in existing publications. Three novel tissue-specific genes were discovered by this approach including AMDHD1 (amidohydrolase domain containing 1) in the liver, PRUNE2 (prune homolog 2) in the heart, and ACVR1C (activin A receptor, type IC) in adipose tissue. We further confirmed the tissue-specific expression of these 3 novel genes by real-time PCR. Among them, ACVR1C is adipose tissue-specific and adipocyte-specific in adipose tissue, and can be used as an adipocyte developmental marker. From GEO profiles, we predicted the processes in which AMDHD1 and PRUNE2 may participate. Our approach provides a novel way to identify new sets of tissue-specific genes and to predict functions in which they may be involved. PMID:23741331

A novel histone variant localized in nucleoli of higher plant cells.

PubMed

Tanaka, I; Akahori, Y; Gomi, K; Suzuki, T; Ueda, K

1999-07-01

Immunofluorescence staining with antisera raised against p35, a basic nuclear protein that accumulates in the pollen nuclei of Lilium longiflorum, specifically stained the nucleoli in interphase nuclei of somatic tissues, including root and leaf, and in pachytene nuclei during meiotic division, whereas antisera raised against histone H1 uniformly stained the entire chromatin domain with the exception of the nucleoli in these nuclei. Further, p35-specific antisera stained the nucleoli in root and leaf nuclei of the monocotyledonous plants Tulipa gesneriana, Allium cepa and Triticum aestivum and of the dicotyledonous plants Vicia faba and Nicotiana tabacum. Thus, these novel antisera stained the nucleoli in cells of all higher plants examined, although the staining patterns within nucleoli were somewhat different among plant species and tissues. The full-length cDNA of p35 was cloned on the basis of the partial amino acid sequence. The deduced amino acid composition and amino acid sequence of p35 indicate that this nucleolar protein is a novel variant of histone Hl. Further, p35 was strongly bound to ribosomal DNA in vitro. The results of immunoblotting of histones extracted from each tissue of the various plant species with the nucleolus-specific antibodies also suggested the conservation of similar epitope(s) in both mono- and dicotyledonous plants. From these results, it is suggested that similar variants of histone Hl are specifically distributed in the nucleoli of all plant species and help to organize the nucleolar chromatin.

Genome-wide prediction and analysis of human tissue-selective genes using microarray expression data

PubMed Central

2013-01-01

Background Understanding how genes are expressed specifically in particular tissues is a fundamental question in developmental biology. Many tissue-specific genes are involved in the pathogenesis of complex human diseases. However, experimental identification of tissue-specific genes is time consuming and difficult. The accurate predictions of tissue-specific gene targets could provide useful information for biomarker development and drug target identification. Results In this study, we have developed a machine learning approach for predicting the human tissue-specific genes using microarray expression data. The lists of known tissue-specific genes for different tissues were collected from UniProt database, and the expression data retrieved from the previously compiled dataset according to the lists were used for input vector encoding. Random Forests (RFs) and Support Vector Machines (SVMs) were used to construct accurate classifiers. The RF classifiers were found to outperform SVM models for tissue-specific gene prediction. The results suggest that the candidate genes for brain or liver specific expression can provide valuable information for further experimental studies. Our approach was also applied for identifying tissue-selective gene targets for different types of tissues. Conclusions A machine learning approach has been developed for accurately identifying the candidate genes for tissue specific/selective expression. The approach provides an efficient way to select some interesting genes for developing new biomedical markers and improve our knowledge of tissue-specific expression. PMID:23369200

Importance of good manufacturing practices in microbiological monitoring in processing human tissues for transplant.

PubMed

Pianigiani, Elisa; Ierardi, Francesca; Fimiani, Michele

2013-12-01

Skin allografts represent an important therapeutic resource in the treatment of severe skin loss. The risk associated with application of processed tissues in humans is very low, however, human material always carries the risk of disease transmission. To minimise the risk of contamination of grafts, processing is carried out in clean rooms where air quality is monitored. Procedures and quality control tests are performed to standardise the production process and to guarantee the final product for human use. Since we only validate and distribute aseptic tissues, we conducted a study to determine what type of quality controls for skin processing are the most suitable for detecting processing errors and intercurrent contamination, and for faithfully mapping the process without unduly increasing production costs. Two different methods for quality control were statistically compared using the Fisher exact test. On the basis of the current study we selected our quality control procedure based on pre- and post-processing tissue controls, operator and environmental controls. Evaluation of the predictability of our control methods showed that tissue control was the most reliable method of revealing microbial contamination of grafts. We obtained 100 % sensitivity by doubling tissue controls, while maintaining high specificity (77 %).

Identification of powdered Chinese herbal medicines by fluorescence microscopy, Part 1: Fluorescent characteristics of mechanical tissues, conducting tissues, and ergastic substances.

PubMed

Wang, Ya-Qiong; Liang, Zhi-Tao; Li, Qin; Yang, Hua; Chen, Hu-Biao; Zhao, Zhong-Zhen; Li, Ping

2011-03-01

The light microscope has been successfully used in identification of Chinese herbal medicines (CHMs) for more than a century. However, positive identification is not always possible. Given the popularity of fluorescence microscopy in bioanalysis, researchers dedicated to finding new ways to identify CHMs more effectively are now turning to fluorescence microscopy for authentication purposes. Some studies on distinguishing confused species from the same genus and on exploring distributions of chemicals in tissues of CHMs by fluorescence microscopy have been reported; however, no systematic investigations on fluorescent characteristics of powdered CHMs have been reported. Here, 46 samples of 16 CHMs were investigated. Specifically, the mechanical tissues including stone cells and fibers, the conducting tissues including three types of vessels, and ergastic substances including crystals of calcium oxalate and secretions, in various powdered CHMs were investigated by both light microscope and fluorescence microscope. The results showed many microscopic features emit fluorescence that makes them easily observed, even against complex backgrounds. Under the fluorescence microscope, different microscopic features from the same powdered CHM or some same features from different powdered CHMs emitted the different fluorescence, making this information very helpful for the authentication of CHMs in powder form. Moreover, secretions with unique chemical profiles from different powdered CHMs showed different fluorescent characteristics. Hence, fluorescence microscopy could be a useful additional method for the authentication of powdered CHMs if the fluorescent characteristics of specific CHMs are known. Copyright © 2010 Wiley-Liss, Inc.

Novel assay for simultaneous measurement of pyridine mononucleotides synthesizing activities allows dissection of the NAD(+) biosynthetic machinery in mammalian cells.

PubMed

Zamporlini, Federica; Ruggieri, Silverio; Mazzola, Francesca; Amici, Adolfo; Orsomando, Giuseppe; Raffaelli, Nadia

2014-11-01

The redox coenzyme NAD(+) is also a rate-limiting co-substrate for several enzymes that consume the molecule, thus rendering its continuous re-synthesis indispensable. NAD(+) biosynthesis has emerged as a therapeutic target due to the relevance of NAD(+) -consuming reactions in complex intracellular signaling networks whose alteration leads to many neurologic and metabolic disorders. Distinct metabolic routes, starting from various precursors, are known to support NAD(+) biosynthesis with tissue/cell-specific efficiencies, probably reflecting differential expression of the corresponding rate-limiting enzymes, i.e. nicotinamide phosphoribosyltransferase, quinolinate phosphoribosyltransferase, nicotinate phosphoribosyltransferase and nicotinamide riboside kinase. Understanding the contribution of these enzymes to NAD(+) levels depending on the tissue/cell type and metabolic status is necessary for the rational design of therapeutic strategies aimed at modulating NAD(+) availability. Here we report a simple, fast and sensitive coupled fluorometric assay that enables simultaneous determination of the four activities in whole-cell extracts and biological fluids. Its application to extracts from various mouse tissues, human cell lines and plasma yielded for the first time an overall picture of the tissue/cell-specific distribution of the activities of the various enzymes. The screening enabled us to gather novel findings, including (a) the presence of quinolinate phosphoribosyltransferase and nicotinamide riboside kinase in all examined tissues/cell lines, indicating that quinolinate and nicotinamide riboside are relevant NAD(+) precursors, and (b) the unexpected occurrence of nicotinate phosphoribosyltransferase in human plasma. © 2014 FEBS.

Smooth muscle-protein translocation and tissue function.

PubMed

Eddinger, Thomas J

2014-09-01

Smooth muscle (SM) tissue is a complex organization of multiple cell types and is regulated by numerous signaling molecules (neurotransmitters, hormones, cytokines, etc.). SM contractile function can be regulated via expression and distribution of the contractile and cytoskeletal proteins, and activation of any of the second messenger pathways that regulate them. Spatial-temporal changes in the contractile, cytoskeletal or regulatory components of SM cells (SMCs) have been proposed to alter SM contractile activity. Ca(2+) sensitization/desensitization can occur as a result of changes at any of these levels, and specific pathways have been identified at all of these levels. Understanding when and how proteins can translocate within the cytoplasm, or to-and-from the plasmalemma and the cytoplasm to alter contractile activity is critical. Numerous studies have reported translocation of proteins associated with the adherens junction and G protein-coupled receptor activation pathways in isolated SMC systems. Specific examples of translocation of vinculin to and from the adherens junction and protein kinase C (PKC) and 17 kDa PKC-potentiated inhibitor of myosin light chain phosphatase (CPI-17) to and from the plasmalemma in isolated SMC systems but not in intact SM tissues are discussed. Using both isolated SMC systems and SM tissues in parallel to pursue these studies will advance our understanding of both the role and mechanism of these pathways as well as their possible significance for Ca(2+) sensitization in intact SM tissues and organ systems. © 2014 Wiley Periodicals, Inc.

SU-E-I-44: Some Preliminary Analysis of Angular Distribution of X-Ray Scattered On Soft Tissues

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

Ganezer, K; Krmar, M; Cvejic, Z

2015-06-15

Purpose: The angular distribution of x-radiation scattered at small angles (up to 16 degrees) from several different animal soft tissue (skin, fat, muscle, retina, etc) were measured using standard equipment devoted to study of crystal structure which provides excellent geometry conditions of measurements. showed measurable differences for different tissues. In the simplest possible case when measured samples do not differ in structure (different concentration solutions) it can be seen that intensity of scattered radiation is decreasing function of the concentration and the peak of the maximum of scattering distribution depends on the concentration as well. Methods: An x-ray scattering profilemore » usually consists of sharp diffraction peak; however some properties of the spatial profiles of scattered radiation as intensity, the peak position, height, area, FWHM, the ratio of peak heights, etc. Results: The data contained measurable differences for different tissues. In the simplest possible case when measured samples do not differ in structure (different concentration solutions) it can be seen that intensity of scattered radiation is decreasing function of the concentration and the peak of the maximum of scattering distribution depends on the concentration as well. Measurements of different samples in the very preliminary phase showed that simple biological material used in study showed slightly different scattering pattern, especially at higher angles (around 10degrees). Intensity of radiation scattered from same tissue type is very dependent on water content and several more parameters. Conclusion: This preliminary study using animal soft tissues on the angular distributions of scattered x-rays suggests that angular distributions of X-rays scattered off of soft tissues might be useful in distinguishing healthy tissue from malignant soft tissue.« less

ROKU: a novel method for identification of tissue-specific genes

PubMed Central

Kadota, Koji; Ye, Jiazhen; Nakai, Yuji; Terada, Tohru; Shimizu, Kentaro

2006-01-01

Background One of the important goals of microarray research is the identification of genes whose expression is considerably higher or lower in some tissues than in others. We would like to have ways of identifying such tissue-specific genes. Results We describe a method, ROKU, which selects tissue-specific patterns from gene expression data for many tissues and thousands of genes. ROKU ranks genes according to their overall tissue specificity using Shannon entropy and detects tissues specific to each gene if any exist using an outlier detection method. We evaluated the capacity for the detection of various specific expression patterns using synthetic and real data. We observed that ROKU was superior to a conventional entropy-based method in its ability to rank genes according to overall tissue specificity and to detect genes whose expression pattern are specific only to objective tissues. Conclusion ROKU is useful for the detection of various tissue-specific expression patterns. The framework is also directly applicable to the selection of diagnostic markers for molecular classification of multiple classes. PMID:16764735

Temperature distributions in tissues during local hyperthermia by stationary or steered beams of unfocused or focused ultrasound.

PubMed Central

Lele, P. P.; Parker, K. J.

1982-01-01

Temperature distributions resulting from insonation with stationary or steered beams of unfocused or focused ultrasound were measured in tissue-equivalent phantom, beef muscle in vitro, dog muscle mass, and transplanted murine tumours in vivo. Arrays of 4 to 6 thermocouples stepped through the volume of interest under computer control were used to measure the steady-state temperatures at 600 to 800 locations in both in vitro and in vivo experiments. The results were confirmed in spontaneous tumours in dog patients using fewer multi-thermocouple probes. Plane wave ultrasound was found to result in spatially non-uniform hyperthermia even in superficial tumours. The region of maximum temperature rise was small in extent and was situated at a depth which varied in the different models from 0.5 to 1.0 cm. Neither its location nor its extent could be varied by spatial manipulations of the transducer or by changing the insonation parameters except the ultrasonic frequency. A second region of hyperthermia was produced at depth by reflective heating if an ultrasonically reflective target, such as bone or air-containing tissue, was located below the target tissue. On the other hand, using available steered, focused ultrasound techniques, tumours (whether situated superficially or at depth) could be heated to a uniform, controllable temperature without undesirable temperature elevation in surrounding normal tissues. The use of steered, focused ultrasound permits deposition of energy to be tailored to the specific needs of each individual tumour. The small size of the focal region enables heating of tumours even when located near ultrasound reflecting targets. PMID:6950746

Real-Time Reverse-Transcription Quantitative Polymerase Chain Reaction Assay Is a Feasible Method for the Relative Quantification of Heregulin Expression in Non-Small Cell Lung Cancer Tissue.

PubMed

Kristof, Jessica; Sakrison, Kellen; Jin, Xiaoping; Nakamaru, Kenji; Schneider, Matthias; Beckman, Robert A; Freeman, Daniel; Spittle, Cindy; Feng, Wenqin

2017-01-01

In preclinical studies, heregulin ( HRG ) expression was shown to be the most relevant predictive biomarker for response to patritumab, a fully human anti-epidermal growth factor receptor 3 monoclonal antibody. In support of a phase 2 study of erlotinib ± patritumab in non-small cell lung cancer (NSCLC), a reverse-transcription quantitative polymerase chain reaction (RT-qPCR) assay for relative quantification of HRG expression from formalin-fixed paraffin-embedded (FFPE) NSCLC tissue samples was developed and validated and described herein. Test specimens included matched FFPE normal lung and NSCLC and frozen NSCLC tissue, and HRG -positive and HRG -negative cell lines. Formalin-fixed paraffin-embedded tissue was examined for functional performance. Heregulin distribution was also analyzed across 200 NSCLC commercial samples. Applied Biosystems TaqMan Gene Expression Assays were run on the Bio-Rad CFX96 real-time PCR platform. Heregulin RT-qPCR assay specificity, PCR efficiency, PCR linearity, and reproducibility were demonstrated. The final assay parameters included the Qiagen FFPE RNA Extraction Kit for RNA extraction from FFPE NSCLC tissue, 50 ng of RNA input, and 3 reference (housekeeping) genes ( HMBS, IPO8 , and EIF2B1 ), which had expression levels similar to HRG expression levels and were stable among FFPE NSCLC samples. Using the validated assay, unimodal HRG distribution was confirmed across 185 evaluable FFPE NSCLC commercial samples. Feasibility of an RT-qPCR assay for the quantification of HRG expression in FFPE NSCLC specimens was demonstrated.

Spatial Systems Lipidomics Reveals Nonalcoholic Fatty Liver Disease Heterogeneity

PubMed Central

2018-01-01

Hepatocellular lipid accumulation characterizes nonalcoholic fatty liver disease (NAFLD). However, the types of lipids associated with disease progression are debated, as is the impact of their localization. Traditional lipidomics analysis using liver homogenates or plasma dilutes and averages lipid concentrations, and does not provide spatial information about lipid distribution. We aimed to characterize the distribution of specific lipid species related to NAFLD severity by performing label-free molecular analysis by mass spectrometry imaging (MSI). Fresh frozen liver biopsies from obese subjects undergoing bariatric surgery (n = 23) with various degrees of NAFLD were cryosectioned and analyzed by matrix-assisted laser desorption/ionization (MALDI)-MSI. Molecular identification was verified by tandem MS. Tissue sections were histopathologically stained, annotated according to the Kleiner classification, and coregistered with the MSI data set. Lipid pathway analysis was performed and linked to local proteome networks. Spatially resolved lipid profiles showed pronounced differences between nonsteatotic and steatotic tissues. Lipid identification and network analyses revealed phosphatidylinositols and arachidonic acid metabolism in nonsteatotic regions, whereas low–density lipoprotein (LDL) and very low–density lipoprotein (VLDL) metabolism was associated with steatotic tissue. Supervised and unsupervised discriminant analysis using lipid based classifiers outperformed simulated analysis of liver tissue homogenates in predicting steatosis severity. We conclude that lipid composition of steatotic and nonsteatotic tissue is highly distinct, implying that spatial context is important for understanding the mechanisms of lipid accumulation in NAFLD. MSI combined with principal component–linear discriminant analysis linking lipid and protein pathways represents a novel tool enabling detailed, comprehensive studies of the heterogeneity of NAFLD. PMID:29570976

Optical pathology of human brain metastasis of lung cancer using combined resonance Raman and spatial frequency spectroscopies

NASA Astrophysics Data System (ADS)

Zhou, Yan; Liu, Cheng-hui; Pu, Yang; Cheng, Gangge; Zhou, Lixin; Chen, Jun; Zhu, Ke; Alfano, Robert R.

2016-03-01

Raman spectroscopy has become widely used for diagnostic purpose of breast, lung and brain cancers. This report introduced a new approach based on spatial frequency spectra analysis of the underlying tissue structure at different stages of brain tumor. Combined spatial frequency spectroscopy (SFS), Resonance Raman (RR) spectroscopic method is used to discriminate human brain metastasis of lung cancer from normal tissues for the first time. A total number of thirty-one label-free micrographic images of normal and metastatic brain cancer tissues obtained from a confocal micro- Raman spectroscopic system synchronously with examined RR spectra of the corresponding samples were collected from the identical site of tissue. The difference of the randomness of tissue structures between the micrograph images of metastatic brain tumor tissues and normal tissues can be recognized by analyzing spatial frequency. By fitting the distribution of the spatial frequency spectra of human brain tissues as a Gaussian function, the standard deviation, σ, can be obtained, which was used to generate a criterion to differentiate human brain cancerous tissues from the normal ones using Support Vector Machine (SVM) classifier. This SFS-SVM analysis on micrograph images presents good results with sensitivity (85%), specificity (75%) in comparison with gold standard reports of pathology and immunology. The dual-modal advantages of SFS combined with RR spectroscopy method may open a new way in the neuropathology applications.

Detrimental and protective fat: body fat distribution and its relation to metabolic disease.

PubMed

Booth, Andrea; Magnuson, Aaron; Foster, Michelle

2014-01-01

Obesity is linked to numerous comorbidities that include, but are not limited to, glucose intolerance, insulin resistance, dyslipidemia, and cardiovascular disease. Current evidence suggests, however, obesity itself is not an exclusive predictor of metabolic dysregulation but rather adipose tissue distribution. Obesity-related adverse health consequences occur predominately in individuals with upper body fat accumulation, the detrimental distribution, commonly associated with visceral obesity. Increased lower body subcutaneous adipose tissue, however, is associated with a reduced risk of obesity-induced metabolic dysregulation and even enhanced insulin sensitivity, thus, storage in this region is considered protective. The proposed mechanisms that causally relate the differential outcomes of adipose tissue distribution are often attributed to location and/or adipocyte regulation. Visceral adipose tissue effluent to the portal vein drains into the liver where hepatocytes are directly exposed to its metabolites and secretory products, whereas the subcutaneous adipose tissue drains systemically. Adipose depots are also inherently different in numerous ways such as adipokine release, immunity response and regulation, lipid turnover, rate of cell growth and death, and response to stress and sex hormones. Proximal extrinsic factors also play a role in the differential drive between adipose tissue depots. This review focuses on the deleterious mechanisms postulated to drive the differential metabolic response between central and lower body adipose tissue distribution.

Construction of Reference Data for Tissue Characterization of Arterial Wall Based on Elasticity Images

NASA Astrophysics Data System (ADS)

Inagaki, Jun; Hasegawa, Hideyuki; Kanai, Hiroshi; Ichiki, Masataka; Tezuka, Fumiaki

2005-06-01

Previously, we developed the phased tracking method [H. Kanai et al.: IEEE Trans. Ultrason. Ferroelectr. Freq. Control 43 (1996) 791] for measuring the minute change in thickness during one heartbeat and the elasticity of the arterial wall. By comparing pathological images with elasticity images measured with ultrasound, elasticity distributions for respective tissues in the arterial wall were determined. We have already measured the elasticity distributions for lipids and fibrous tissues (mixtures of smooth-muscle and collagen fiber) [H. Kanai et al.: Circulation 107 (2003) 3018]. In this study, elasticity distributions were measured for blood clots and calcified tissues. We discuss whether these elasticity distributions, which were measuerd in vitro, can be used as reference data for classifying cross-sectional elasticity images measured in vivo into respective tissues. In addition to the measurement of elasticity distributions, correlations between collagen content and elasticity were investigated with respect to fibrous tissue to estimate the collagen and smooth-muscle content based on elasticity. Collagen and smooth-muscle content may be important factors in determining the stability of the fibrous cap of atherosclerotic plaque. Therefore, correlations between elasticity and elements of the tissue in the arterial wall may provide useful information for the noninvasive diagnosis of plaque vulnerability.

X-ray computed tomography imaging of a tumor with high sensitivity using gold nanoparticles conjugated to a cancer-specific antibody via polyethylene glycol chains on their surface

NASA Astrophysics Data System (ADS)

Nakagawa, Tomohiko; Gonda, Kohsuke; Kamei, Takashi; Cong, Liman; Hamada, Yoh; Kitamura, Narufumi; Tada, Hiroshi; Ishida, Takanori; Aimiya, Takuji; Furusawa, Naoko; Nakano, Yasushi; Ohuchi, Noriaki

2016-01-01

Contrast agents are often used to enhance the contrast of X-ray computed tomography (CT) imaging of tumors to improve diagnostic accuracy. However, because the iodine-based contrast agents currently used in hospitals are of low molecular weight, the agent is rapidly excreted from the kidney or moves to extravascular tissues through the capillary vessels, depending on its concentration gradient. This leads to nonspecific enhancement of contrast images for tissues. Here, we created gold (Au) nanoparticles as a new contrast agent to specifically image tumors with CT using an enhanced permeability and retention (EPR) effect. Au has a higher X-ray absorption coefficient than does iodine. Au nanoparticles were supported with polyethylene glycol (PEG) chains on their surface to increase the blood retention and were conjugated with a cancer-specific antibody via terminal PEG chains. The developed Au nanoparticles were injected into tumor-bearing mice, and the distribution of Au was examined with CT imaging, transmission electron microscopy, and elemental analysis using inductively coupled plasma optical emission spectrometry. The results show that specific localization of the developed Au nanoparticles in the tumor is affected by a slight difference in particle size and enhanced by the conjugation of a specific antibody against the tumor.

Genetics and physiology of cell wall polysaccharides in the model C4 grass, Setaria viridis spp.

PubMed

Ermawar, Riksfardini A; Collins, Helen M; Byrt, Caitlin S; Henderson, Marilyn; O'Donovan, Lisa A; Shirley, Neil J; Schwerdt, Julian G; Lahnstein, Jelle; Fincher, Geoffrey B; Burton, Rachel A

2015-10-02

Setaria viridis has emerged as a model species for the larger C4 grasses. Here the cellulose synthase (CesA) superfamily has been defined, with an emphasis on the amounts and distribution of (1,3;1,4)-β-glucan, a cell wall polysaccharide that is characteristic of the grasses and is of considerable value for human health. Orthologous relationship of the CesA and Poales-specific cellulose synthase-like (Csl) genes among Setaria italica (Si), Sorghum bicolor (Sb), Oryza sativa (Os), Brachypodium distachyon (Bradi) and Hordeum vulgare (Hv) were compared using bioinformatics analysis. Transcription profiling of Csl gene families, which are involved in (1,3;1,4)-β-glucan synthesis, was performed using real-time quantitative PCR (Q-PCR). The amount of (1,3;1,4)-β-glucan was measured using a modified Megazyme assay. The fine structures of the (1,3;1,4)-β-glucan, as denoted by the ratio of cellotriosyl to cellotetraosyl residues (DP3:DP4 ratio) was assessed by chromatography (HPLC and HPAEC-PAD). The distribution and deposition of the MLG was examined using the specific antibody BG-1 and captured using fluorescence and transmission electron microscopy (TEM). The cellulose synthase gene superfamily contains 13 CesA and 35 Csl genes in Setaria. Transcript profiling of CslF, CslH and CslJ gene families across a vegetative tissue series indicated that SvCslF6 transcripts were the most abundant relative to all other Csl transcripts. The amounts of (1,3;1,4)-β-glucan in Setaria vegetative tissues ranged from 0.2% to 2.9% w/w with much smaller amounts in developing grain (0.003% to 0.013% w/w). In general, the amount of (1,3;1,4)-β-glucan was greater in younger than in older tissues. The DP3:DP4 ratios varied between tissue types and across developmental stages, and ranged from 2.4 to 3.0:1. The DP3:DP4 ratios in developing grain ranged from 2.5 to 2.8:1. Micrographs revealing the distribution of (1,3;1,4)-β-glucan in walls of different cell types and the data were consistent with the quantitative (1,3;1,4)-β-glucan assays. The characteristics of the cellulose synthase gene superfamily and the accumulation and distribution of (1,3;1,4)-β-glucans in Setaria are similar to those in other C4 grasses, including sorghum. This suggests that Setaria is a suitable model plant for cell wall polysaccharide biology in C4 grasses.

Molecular basis of the dopaminergic system in the cricket Gryllus bimaculatus.

PubMed

Watanabe, Takayuki; Sadamoto, Hisayo; Aonuma, Hitoshi

2013-12-01

In insects, dopamine modulates various aspects of behavior such as learning and memory, arousal and locomotion, and is also a precursor of melanin. To elucidate the molecular basis of the dopaminergic system in the field cricket Gryllus bimaculatus DeGeer, we identified genes involved in dopamine biosynthesis, signal transduction, and dopamine re-uptake in the cricket. Complementary DNA of two isoforms of tyrosine hydroxylase (TH), which convert tyrosine into L-3,4-dihydroxyphenylalanine, was isolated from the cricket brain cDNA library. In addition, four dopamine receptor genes (Dop1, Dop2, Dop3, and DopEcR) and a high-affinity dopamine transporter gene were identified. The two TH isoforms contained isoform-specific regions in the regulatory ACT domain and showed differential expression patterns in different tissues. In addition, the dopamine receptor genes had a receptor subtype-specific distribution: the Dop1, Dop2, and DopEcR genes were broadly expressed in various tissues at differential expression levels, and the Dop3 gene was restrictedly expressed in neuronal tissues and the testicles. Our findings provide a fundamental basis for understanding the dopaminergic regulation of diverse physiological processes in the cricket.

Localization of trefoil factor family peptide 3 (TFF3) in epithelial tissues originating from the three germ layers of developing mouse embryo.

PubMed

Bijelić, Nikola; Belovari, Tatjana; Tolušić Levak, Maja; Baus Lončar, Mirela

2017-08-20

Trefoil factor family (TFF) peptides are involved in the maintenance of epithelial integrity and epithelial restitution. Mature epithelial tissues originate from different embryonic germ layers. The objective of this research was to explore the presence and localization of TFF3 peptide in mouse embryonic epithelia and to examine if the occurrence of TFF3 peptide is germ layer-dependent. Mouse embryos (14-18 days old) were fixed in 4% paraformaldehyde and embedded in paraffin. Immunohistochemistry was performed with affinity purified rabbit anti-TFF3 antibody, goat anti-rabbit biotinylated secondary antibody and streptavidin-horseradish peroxidase, followed by 3,3'-diaminobenzidine. TFF3 peptide was present in the gastric and intestinal mucosa, respiratory mucosa in the upper and lower airways, pancreas, kidney tubules, epidermis, and oral cavity. The presence and localization of TFF3 peptide was associated with the embryonic stage and tissue differentiation. TFF3 peptide distribution specific to the germ layers was not observed. The role of TFF3 peptide in cell migration and differentiation, immune response, and apoptosis might be associated with specific embryonic epithelial cells. TFF3 peptide may also be considered as a marker for mucosal maturation.

Immunocytochemical localization of carbonic anhydrase in the pseudobranch tissue of the rainbow trout Oncorhynchus mykiss.

PubMed

Rahim, S M; Mazlan, A G; Simon, K D; Delaunoy, J P; Laurent, P

2014-02-01

Pseudobranch function has long interested scientists, but its role has yet to be elucidated. Several studies have suggested that pseudobranchs serve respiratory, osmoregulatory, and sensory functions. This work investigated the immunolocalization of pseudobranch carbonic anhydrase (CA) in the teleost fish species rainbow trout (Oncorhynchus mykiss) to clarify its physiological function. CA was purified from rainbow trout gills O. mykiss and specific antibodies were raised. Immunoblotting between tissue homogenates of pseudobranch and gill CA antibodies showed specific immunostaining with only one band corresponding to CA in the pseudobranch homogenate. Results of immunohistochemical technique revealed that CA was distributed within pseudobranch cells and more precisely in the apical parts (anti-vascular) of cells. The basal (vascular) parts of cells, tubular system, blood capillaries, and pillar cells were not immunostained. Immunocytochemistry confirmed these results and showed that some CA enzyme was cytoplasmic and the remainder was linked to membranous structures. The results also showed that the lacunar tissue layers did not display immunoperoxidase activity. Our results indicated that pseudobranch CA may have a function related to the extracellular medium wherein CA intervenes with the mechanism of stimulation of afferent nerve fibers.

Void space inside the developing seed of Brassica napus and the modelling of its function

PubMed Central

Verboven, Pieter; Herremans, Els; Borisjuk, Ljudmilla; Helfen, Lukas; Ho, Quang Tri; Tschiersch, Henning; Fuchs, Johannes; Nicolaï, Bart M; Rolletschek, Hardy

2013-01-01

The developing seed essentially relies on external oxygen to fuel aerobic respiration, but it is currently unknown how oxygen diffuses into and within the seed, which structural pathways are used and what finally limits gas exchange. By applying synchrotron X-ray computed tomography to developing oilseed rape seeds we uncovered void spaces, and analysed their three-dimensional assembly. Both the testa and the hypocotyl are well endowed with void space, but in the cotyledons, spaces were small and poorly inter-connected. In silico modelling revealed a three orders of magnitude range in oxygen diffusivity from tissue to tissue, and identified major barriers to gas exchange. The oxygen pool stored in the voids is consumed about once per minute. The function of the void space was related to the tissue-specific distribution of storage oils, storage protein and starch, as well as oxygen, water, sugars, amino acids and the level of respiratory activity, analysed using a combination of magnetic resonance imaging, specific oxygen sensors, laser micro-dissection, biochemical and histological methods. We conclude that the size and inter-connectivity of void spaces are major determinants of gas exchange potential, and locally affect the respiratory activity of a developing seed. PMID:23692271

Regional distribution of ependymins in goldfish brain measured by radioimmunoassay.

PubMed

Schmidt, R; Lapp, H

1987-01-01

Ependymins are goldfish glycoproteins known to participate in biochemical reactions of memory consolidation after an operant vestibulomotor training-task. The distribution of these proteins was analysed by means of a highly sensitive and specific radioimmunoassay. Ependymins were shown to be characteristic constituents of the nervous system, but they were virtually absent from all other tissues investigated. They were widely distributed over many brain regions and particularly enriched in mesencephalic structures. In the optic tectum, the tegmentum and in the vagal lobes ependymins constituted 3.2, 2.8 and 3.5%, respectively, of the total protein content. The highest steady-state concentration of ependymins (15.4% of protein) was measured, however, in the brain extracellular fluid including the cerebrospinal fluid. Lactate dehydrogenase activity was monitored to demonstrate that only negligible amounts of cytoplasmic constituents were released during the collection of extracellular proteins. Ependymin concentrations were lower in those brain areas which contain few cell bodies, but many glial and fibrous elements. The specific distribution of the intrinsic ependymins was compared with that of intracerebroventricularly injected [(125)I]-labeled ependymin. This exogenous marker substance was quickly incorporated and then cleared rapidly from the central nervous system with a half-life of 2 h. Our quantitative analysis of the distribution of ependymins reveals that they are specific major constituents of the goldfish nervous system. Their fast turnover, their wide distribution over many brain regions, with some enrichment in mesencephalic structures, and especially their very high concentration in the extracellular brain fluid suggest that ependymins may act on neuronal membranes from the extracellular fluid.

Whole breast tissue characterization with ultrasound tomography

NASA Astrophysics Data System (ADS)

Duric, Neb; Littrup, Peter; Li, Cuiping; Roy, Olivier; Schmidt, Steve; Seamans, John; Wallen, Andrea; Bey-Knight, Lisa

2015-03-01

A number of clinical trials have shown that screening ultrasound, supplemental to mammography, detects additional cancers in women with dense breasts. However, labor intensity, operator dependence and high recall rates have limited adoption. This paper describes the use of ultrasound tomography for whole-breast tissue stiffness measurements as a first step toward addressing the issue of high recall rates. The validation of the technique using an anthropomorphic phantom is described. In-vivo applications are demonstrated on 13 breast masses, indicating that lesion stiffness correlates with lesion type as expected. Comparison of lesion stiffness measurements with standard elastography was available for 11 masses and showed a strong correlation between the 2 measures. It is concluded that ultrasound tomography can map out the 3 dimensional distribution of tissue stiffness over the whole breast. Such a capability is well suited for screening where additional characterization may improve the specificity of screening ultrasound, thereby lowering barriers to acceptance.

Distribution of gluten proteins in bread wheat (Triticum aestivum) grain.

PubMed

Tosi, Paola; Gritsch, Cristina Sanchis; He, Jibin; Shewry, Peter R

2011-07-01

Gluten proteins are the major storage protein fraction in the mature wheat grain. They are restricted to the starchy endosperm, which forms white flour on milling, and interact during grain development to form large polymers which form a continuous proteinaceous network when flour is mixed with water to give dough. This network confers viscosity and elasticity to the dough, enabling the production of leavened products. The starchy endosperm is not a homogeneous tissue and quantitative and qualitative gradients exist for the major components: protein, starch and cell wall polysaccharides. Gradients in protein content and composition are the most evident and are of particular interest because of the major role played by the gluten proteins in determining grain processing quality. Protein gradients in the starchy endosperm were investigated using antibodies for specific gluten protein types for immunolocalization in developing grains and for western blot analysis of protein extracts from flour fractions obtained by sequential abrasion (pearling) to prepare tissue layers. Differential patterns of distribution were found for the high-molecular-weight subunits of glutenin (HMW-GS) and γ-gliadins when compared with the low-molecular-weight subunits of glutenin (LMW-GS), ω- and α-gliadins. The first two types of gluten protein are more abundant in the inner endosperm layers and the latter more abundant in the subaleurone. Immunolocalization also showed that segregation of gluten proteins occurs both between and within protein bodies during protein deposition and may still be retained in the mature grain. Quantitative and qualitative gradients in gluten protein composition are established during grain development. These gradients may be due to the origin of subaleurone cells, which unlike other starchy endosperm cells derive from the re-differentiation of aleurone cells, but could also result from the action of specific regulatory signals produced by the maternal tissue on specific domains of the gluten protein gene promoters.

Distribution of gluten proteins in bread wheat (Triticum aestivum) grain

PubMed Central

Tosi, Paola; Gritsch, Cristina Sanchis; He, Jibin; Shewry, Peter R.

2011-01-01

Background and Aims Gluten proteins are the major storage protein fraction in the mature wheat grain. They are restricted to the starchy endosperm, which forms white flour on milling, and interact during grain development to form large polymers which form a continuous proteinaceous network when flour is mixed with water to give dough. This network confers viscosity and elasticity to the dough, enabling the production of leavened products. The starchy endosperm is not a homogeneous tissue and quantitative and qualitative gradients exist for the major components: protein, starch and cell wall polysaccharides. Gradients in protein content and composition are the most evident and are of particular interest because of the major role played by the gluten proteins in determining grain processing quality. Methods Protein gradients in the starchy endosperm were investigated using antibodies for specific gluten protein types for immunolocalization in developing grains and for western blot analysis of protein extracts from flour fractions obtained by sequential abrasion (pearling) to prepare tissue layers. Key Results Differential patterns of distribution were found for the high-molecular-weight subunits of glutenin (HMW-GS) and γ-gliadins when compared with the low-molecular-weight subunits of glutenin (LMW-GS), ω- and α-gliadins. The first two types of gluten protein are more abundant in the inner endosperm layers and the latter more abundant in the subaleurone. Immunolocalization also showed that segregation of gluten proteins occurs both between and within protein bodies during protein deposition and may still be retained in the mature grain. Conclusions Quantitative and qualitative gradients in gluten protein composition are established during grain development. These gradients may be due to the origin of subaleurone cells, which unlike other starchy endosperm cells derive from the re-differentiation of aleurone cells, but could also result from the action of specific regulatory signals produced by the maternal tissue on specific domains of the gluten protein gene promoters. PMID:21693664

An informatics model for tissue banks--lessons learned from the Cooperative Prostate Cancer Tissue Resource.

PubMed

Patel, Ashokkumar A; Gilbertson, John R; Parwani, Anil V; Dhir, Rajiv; Datta, Milton W; Gupta, Rajnish; Berman, Jules J; Melamed, Jonathan; Kajdacsy-Balla, Andre; Orenstein, Jan; Becich, Michael J

2006-05-05

Advances in molecular biology and growing requirements from biomarker validation studies have generated a need for tissue banks to provide quality-controlled tissue samples with standardized clinical annotation. The NCI Cooperative Prostate Cancer Tissue Resource (CPCTR) is a distributed tissue bank that comprises four academic centers and provides thousands of clinically annotated prostate cancer specimens to researchers. Here we describe the CPCTR information management system architecture, common data element (CDE) development, query interfaces, data curation, and quality control. Data managers review the medical records to collect and continuously update information for the 145 clinical, pathological and inventorial CDEs that the Resource maintains for each case. An Access-based data entry tool provides de-identification and a standard communication mechanism between each group and a central CPCTR database. Standardized automated quality control audits have been implemented. Centrally, an Oracle database has web interfaces allowing multiple user-types, including the general public, to mine de-identified information from all of the sites with three levels of specificity and granularity as well as to request tissues through a formal letter of intent. Since July 2003, CPCTR has offered over 6,000 cases (38,000 blocks) of highly characterized prostate cancer biospecimens, including several tissue microarrays (TMA). The Resource developed a website with interfaces for the general public as well as researchers and internal members. These user groups have utilized the web-tools for public query of summary data on the cases that were available, to prepare requests, and to receive tissues. As of December 2005, the Resource received over 130 tissue requests, of which 45 have been reviewed, approved and filled. Additionally, the Resource implemented the TMA Data Exchange Specification in its TMA program and created a computer program for calculating PSA recurrence. Building a biorepository infrastructure that meets today's research needs involves time and input of many individuals from diverse disciplines. The CPCTR can provide large volumes of carefully annotated prostate tissue for research initiatives such as Specialized Programs of Research Excellence (SPOREs) and for biomarker validation studies and its experience can help development of collaborative, large scale, virtual tissue banks in other organ systems.

Issues in collecting, processing and storing human tissues and associated information to support biomedical research.

PubMed

Grizzle, William E; Bell, Walter C; Sexton, Katherine C

2010-01-01

The availability of human tissues to support biomedical research is critical to advance translational research focused on identifying and characterizing approaches to individualized (personalized) medical care. Providing such tissues relies on three acceptable models - a tissue banking model, a prospective collection model and a combination of these two models. An unacceptable model is the "catch as catch can" model in which tissues are collected, processed and stored without goals or a plan or without standard operating procedures, i.e., portions of tissues are collected as available and processed and stored when time permits. In the tissue banking model, aliquots of tissues are collected according to SOPs. Usually specific sizes and types of tissues are collected and processed (e.g., 0.1 gm of breast cancer frozen in OCT). Using the banking model, tissues may be collected that may not be used and/or do not meet specific needs of investigators; however, at the time of an investigator request, tissues are readily available as is clinical information including clinical outcomes. In the model of prospective collection, tissues are collected based upon investigator requests including specific requirements of investigators. For example, the investigator may request that two 0.15 gm matching aliquots of breast cancer be minced while fresh, put in RPMI media with and without fetal calf serum, cooled to 4°C and shipped to the investigator on wet ice. Thus, the tissues collected prospectively meet investigator needs, all collected specimens are utilized and storage of specimens is minimized; however, investigators must wait until specimens are collected, and if needed, for clinical outcome. The operation of any tissue repository requires well trained and dedicated personnel. A quality assurance program is required which provides quality control information on the diagnosis of a specimen that is matched specifically to the specimen provided to an investigator instead of an overall diagnosis of the specimen via a surgical pathology report. This is necessary because a specific specimen may not match the diagnosis of the case due to many factors such as necrosis, unsuspected tumor invasion of apparently normal tissue, and areas of fibrosis which are mistaken grossly for tumor. Aliquots for quality control (QC) may or may not be collected at the time of collection and in some cases, QC may not occur until specimens are distributed to investigators. In establishing a tumor repository, multiple issues need to be considered. These include the available resources, long term support, space and equipment. The needs of the potential users need to be identified as to the types of tissues and services needed and the annotation expected. Other specific issues to be considered include collection of specimens potentially infected with blood borne pathogens (e.g., hepatitis B), charge back mechanisms, informatics needs and support, and investigator requirements (e.g., recognition of repository contributions in publications). In general, the repository should not perform the research of the investigators, but should provide the infrastructure necessary to support the research of the investigator. Thus, the goals of the repository must be established. Similarly, ethical and regulatory issues must be evaluated. In general, tissue repositories need ethical (e.g., IRB) and privacy (e.g., HIPAA) review. Also, safety issues need to be considered as well as how biohazards will be addressed by investigator-users. Considerations involving the transfer of specimens to other organization usually require a material transfer agreement (MTA). A MTA should address biohazards as well as indemnification. Thus, many issues must be considered and addressed in order to establish and operate successfully a biorepository.

A taxonomy of epithelial human cancer and their metastases

PubMed Central

2009-01-01

Background Microarray technology has allowed to molecularly characterize many different cancer sites. This technology has the potential to individualize therapy and to discover new drug targets. However, due to technological differences and issues in standardized sample collection no study has evaluated the molecular profile of epithelial human cancer in a large number of samples and tissues. Additionally, it has not yet been extensively investigated whether metastases resemble their tissue of origin or tissue of destination. Methods We studied the expression profiles of a series of 1566 primary and 178 metastases by unsupervised hierarchical clustering. The clustering profile was subsequently investigated and correlated with clinico-pathological data. Statistical enrichment of clinico-pathological annotations of groups of samples was investigated using Fisher exact test. Gene set enrichment analysis (GSEA) and DAVID functional enrichment analysis were used to investigate the molecular pathways. Kaplan-Meier survival analysis and log-rank tests were used to investigate prognostic significance of gene signatures. Results Large clusters corresponding to breast, gastrointestinal, ovarian and kidney primary tissues emerged from the data. Chromophobe renal cell carcinoma clustered together with follicular differentiated thyroid carcinoma, which supports recent morphological descriptions of thyroid follicular carcinoma-like tumors in the kidney and suggests that they represent a subtype of chromophobe carcinoma. We also found an expression signature identifying primary tumors of squamous cell histology in multiple tissues. Next, a subset of ovarian tumors enriched with endometrioid histology clustered together with endometrium tumors, confirming that they share their etiopathogenesis, which strongly differs from serous ovarian tumors. In addition, the clustering of colon and breast tumors correlated with clinico-pathological characteristics. Moreover, a signature was developed based on our unsupervised clustering of breast tumors and this was predictive for disease-specific survival in three independent studies. Next, the metastases from ovarian, breast, lung and vulva cluster with their tissue of origin while metastases from colon showed a bimodal distribution. A significant part clusters with tissue of origin while the remaining tumors cluster with the tissue of destination. Conclusion Our molecular taxonomy of epithelial human cancer indicates surprising correlations over tissues. This may have a significant impact on the classification of many cancer sites and may guide pathologists, both in research and daily practice. Moreover, these results based on unsupervised analysis yielded a signature predictive of clinical outcome in breast cancer. Additionally, we hypothesize that metastases from gastrointestinal origin either remember their tissue of origin or adapt to the tissue of destination. More specifically, colon metastases in the liver show strong evidence for such a bimodal tissue specific profile. PMID:20017941

Effect of Heterogeneity of Tissues on RF Energy Absorption in the Brain for Exposure Assessment in Epidemiological Studies on Mobile Phone Use and Brain Tumors

NASA Astrophysics Data System (ADS)

Varsier, Nadege; Wake, Kanako; Taki, Masao; Watanabe, Soichi

We compared SAR distributions in major anatomical structures of the brain of a homogeneous and a heterogeneous model using FDTD calculations. Our results proved a good correlation between SAR values in lobes of the brain where tumors may arise more frequently. However SAR values at some specific locations were shown to be under or overestimated.

[Analysis of heat transfer in the biological tissue layer with distributed system of blood vessels].

PubMed

Bogatov, N M; Pelipenko, O N

2005-09-01

Processes of heat transfer in the skin layer with blood vessels were investigated using mathematical modeling. Analysis of influence of a pathological state of blood vessels on heterogeneity of thermal field of the skin surface was carried out. For each site of body surface, there is a certain difference of temperature between normal and pathological sites, being specific for differential diagnosis of diseases of dermal and hypodermic vessels.

Investigating energy deposition within cell populations using Monte Carlo simulations.

PubMed

Oliver, Patricia A K; Thomson, Rowan M

2018-06-27

In this work, we develop multicellular models of healthy and cancerous human soft tissues, which are used to investigate energy deposition in subcellular targets, quantify the microdosimetric spread in a population of cells, and determine how these results depend on model details. Monte Carlo (MC) tissue models combining varying levels of detail on different length scales are developed: microscopically-detailed regions of interest (>1500 explicitly-modelled cells) are embedded in bulk tissue phantoms irradiated by photons (20 keV to 1.25 MeV). Specific energy (<i>z</i>; energy imparted per unit mass) is scored in nuclei and cytoplasm compartments using the EGSnrc user-code egs_chamber; specific energy mean, <<i>z</i>>, standard deviation, <i>σ</i>_<i>z</i>, and distribution, <i>f</i>(<i>z</i>,<i>D</i>), are calculated for a variety of macroscopic doses, <i>D</i>. MC-calculated <i>f</i>(<i>z</i>,<i>D</i>) are compared with normal distributions having the same mean and standard deviation. For mGy doses, there is considerable variation in energy deposition (microdosimetric spread) throughout a cell population: <i>e</i>.<i>g</i>., for 30 keV photons irradiating melanoma with 7.5 μm cell radius and 3 μm nuclear radius, <i>σ</i>_<i>z</i>/<<i>z</i>> for nuclear targets is 170%, and the fraction of nuclei receiving no energy deposition, <i>f</i>_<i>z</i>=0, is 0.31 for a dose of 10 mGy. If cobalt-60 photons are considered instead, then <i>σ</i>_<i>z</i>/<<i>z</i>> decreases to 84%, and <i>f</i>_<i>z</i>=0 decreases to 0.036. These results correspond to randomly arranged cells with cell/nucleus sizes randomly sampled from a normal distribution with a standard deviation of 1 μm. If cells are arranged in a hexagonal lattice and cell/nucleus sizes are uniform throughout the population, then <i>σ</i>_<i>z</i>/<<i>z</i>> decreases to 106% and 68% for 30 keV and cobalt-60,respectively; <i>f</i>_<i>z</i>=0 decreases to 0.25 and 0.00094 for 30 keV and cobalt-60, respectively. Thus, specific energy distributions are sensitive to cell/nucleus sizes and their distributions: variations in specific energy deposited over a cell population are underestimated if targets are assumed to be uniform in size compared with more realistic variation in target size. Bulk tissue dose differs from <<i>z</i>> for nuclei (cytoplasms) by up to 21% (12%) across all cell/nucleus sizes, bulk tissues, and incident photon energies, considering a 50 mGy dose level. Overall, results demonstrate the importance of microdosimetric considerations at low doses, and indicate the sensitivity of energy deposition within subcellular targets to incident photon energy, dose level, elemental compositions, and microscopic tissue model. © 2018 Institute of Physics and Engineering in Medicine.

The Search for a Subtype-Selective PET Imaging Agent for the GABAA Receptor Complex: Evaluation of the Radiotracer [11C]ADO in Nonhuman Primates.

PubMed

Lin, Shu-Fei; Bois, Frederic; Holden, Daniel; Nabulsi, Nabeel; Pracitto, Richard; Gao, Hong; Kapinos, Michael; Teng, Jo-Ku; Shirali, Anupama; Ropchan, Jim; Carson, Richard E; Elmore, Charles S; Vasdev, Neil; Huang, Yiyun

2017-01-01

The myriad physiological functions of γ-amino butyric acid (GABA) are mediated by the GABA-benzodiazepine receptor complex comprising of the GABA A , GABA B , and GABA C groups. The various GABA A subunits with region-specific distributions in the brain subserve different functional and physiological roles. For example, the sedative and anticonvulsive effects of classical benzodiazepines are attributed to the α 1 subunit, and the α 2 and α 3 subunits mediate the anxiolytic effect. To optimize pharmacotherapies with improved efficacy and devoid of undesirable side effects for the treatment of anxiety disorders, subtype-selective imaging radiotracers are required to assess target engagement at GABA sites and determine the dose-receptor occupancy relationships. The goal of this work was to characterize, in nonhuman primates, the in vivo binding profile of a novel positron emission tomography (PET) radiotracer, [ 11 C]ADO, which has been indicated to have functional selectivity for the GABA A α 2 /α 3 subunits. High specific activity [ 11 C]ADO was administrated to 3 rhesus monkeys, and PET scans of 120-minute duration were performed on the Focus-220 scanner. In the blood, [ 11 C]ADO metabolized at a fairly rapid rate, with ∼36% of the parent tracer remaining at 30 minutes postinjection. Uptake levels of [ 11 C]ADO in the brain were high (peak standardized uptake value of ∼3.0) and consistent with GABA A distribution, with highest activity levels in cortical areas, intermediate levels in cerebellum and thalamus, and lowest uptake in striatal regions and amygdala. Tissue kinetics was fast, with peak uptake in all brain regions within 20 minutes of tracer injection. The one-tissue compartment model provided good fits to regional time-activity curves and reliable measurement of kinetic parameters. The absolute test-retest variability of regional distribution volumes ( V T ) was low, ranging from 4.5% to 8.7%. Pretreatment with flumazenil (a subtype nonselective ligand, 0.2 mg/kg, intravenous [IV], n = 1), Ro15-4513 (an α 5 -selective ligand, 0.03 mg/kg, IV, n = 2), and zolpidem (an α 1 -selective ligand, 1.7 mg/kg, IV, n = 1) led to blockade of [ 11 C]ADO binding by 96.5%, 52.5%, and 76.5%, respectively, indicating the in vivo binding specificity of the radiotracer. Using the nondisplaceable volume of distribution ( V ND ) determined from the blocking studies, specific binding signals, as measured by values of regional binding potential ( BP ND ), ranged from 0.6 to 4.4, which are comparable to those of [ 11 C]flumazenil. In conclusion, [ 11 C]ADO was demonstrated to be a specific radiotracer for the GABA A receptors with several favorable properties: high brain uptake, fast tissue kinetics, and high levels of specific binding in nonhuman primates. However, subtype selectivity in vivo is not obvious for the radiotracer, and thus, the search for subtype-selective GABA A radiotracers continues.

Developing a clinically viable angle-resolved low coherence interferometry optical biopsy system

NASA Astrophysics Data System (ADS)

Pyhtila, John W.

2007-12-01

Non-invasive optical biopsy techniques, which interrogate tissue in situ, offer a potential method to improve the detection of dysplasia, a pre-cancerous tissue state. Specifically, monitoring of Barrett's esophagus (BE) patients for dysplasia, currently done through systematic biopsy, can be improved by increasing the proportion of at-risk tissue examined. Angle-resolved low coherence interferometry (a/LCI) is an optical spectroscopic technique which measures the depth resolved nuclear morphology of tissue, a key biomarker for identifying dysplasia. Using an animal carcinogenesis model, it was shown that a/LCI can detect dysplasia with great sensitivity and specificity. However, for the clinical application of a/LCI, numerous hurdles must be overcome. This dissertation presents the development of three new a/LCI systems which incrementally address the three main obstacles preventing the clinical application of a/LCI. First, data acquisition time is reduced by implementing a frequency-domain detection scheme using an imaging spectrograph that collects the complete depth resolved angular scattering distribution in parallel. This advance reduces data collection time to a clinically acceptable 40 ms. Second, a fiber probe is developed to enable the endoscopic application of a/LCI. The probe incorporates a single fiber for delivering light and a coherent fiber bundle for collecting the angular distribution of scattered light. Third, a portable device is created through miniaturization of the optical design, and a flexible fiber probe is created using polarization maintaining fiber to deliver the light. These advances allow for the clinical application of the system to ex vivo human tissue samples. The performance of each described system is evaluated through a number of validation studies, including the sizing of polystyrene microspheres, a typical model used in light scattering studies, and the measurement of in vitro cell nuclear diameters, accomplished with sub-wavelength precision and accuracy. The culmination of this work is the first human study using a/LCI in which it is demonstrated that a/LCI depth resolved nuclear morphology measurements provide an excellent means to identify dysplasia in BE patients. The described results demonstrate the great potential for the in vivo application of a/LCI as a targeting mechanism for the detection of dysplasia in Barrett's esophagus patients.

Egg serpins: The chicken and/or the egg dilemma.

PubMed

Dombre, Clara; Guyot, Nicolas; Moreau, Thierry; Monget, Philippe; Da Silva, Mylène; Gautron, Joël; Réhault-Godbert, Sophie

2017-02-01

Twenty-seven serpins belonging to clade A, B, C, D, E, F, G, H and I serpins are currently referenced in chicken genome databases. Phylogenetic analysis of chicken serpins revealed that ovalbumin (Serpinb14) and its paralogs ovalbumin-related protein Y (Serpinb14b) and ovalbumin-related protein X (Serpinb14c) are found in bird species. These clade B serpins are specifically expressed in reproductive tissues and exported in the egg where they constitute major protein components. These data suggest that these three paralogs have probably appeared in birds to face new environments and ensure the extra-uterine development of an embryo in a shell egg. Twelve other serpins have been identified in the newly produced egg, some of them having a specific distribution in the respective egg structures (eggshell, egg white, vitelline membrane and egg yolk). The physiological role of these egg serpins remain largely unexplored, but there is increasing evidence in literature or by homologies with their mammalian counterparts, that some of them participate in cell proliferation, tissue remodeling and/or angiogenesis associated with folliculogenesis and development of extraembryonic structures, eggshell biomineralization, egg defense and nutrition of the embryo. A better knowledge of the phylogenetic evolution of these 15 serpins in other oviparous species, on their egg distribution, on their regulation during embryonic development (activation/degradation/transfer) and on their functional specificity, is needed to better appreciate their role and their bird-specificity. These review shed light on the multiple possibilities that offer the avian egg model to study the role of serpins in reproduction and developmental biology. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Imaging Taurine in the Central Nervous System Using Chemically Specific X-ray Fluorescence Imaging at the Sulfur K-Edge

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

Hackett, Mark J.; Paterson, Phyllis G.; Pickering, Ingrid J.

A method to image taurine distributions within the central nervous system and other organs has long been sought. Since taurine is small and mobile, it cannot be chemically “tagged” and imaged using conventional immuno-histochemistry methods. Combining numerous indirect measurements, taurine is known to play critical roles in brain function during health and disease and is proposed to act as a neuro-osmolyte, neuro-modulator, and possibly a neuro-transmitter. Elucidation of taurine’s neurochemical roles and importance would be substantially enhanced by a direct method to visualize alterations, due to physiological and pathological events in the brain, in the local concentration of taurine atmore » or near cellular spatial resolution in vivo or in situ in tissue sections. We thus have developed chemically specific X-ray fluorescence imaging (XFI) at the sulfur K-edge to image the sulfonate group in taurine in situ in ex vivo tissue sections. To our knowledge, this represents the first undistorted imaging of taurine distribution in brain at 20 μm resolution. We report quantitative technique validation by imaging taurine in the cerebellum and hippocampus regions of the rat brain. Further, we apply the technique to image taurine loss from the vulnerable CA1 (cornus ammonis 1) sector of the rat hippocampus following global brain ischemia. The location-specific loss of taurine from CA1 but not CA3 neurons following ischemia reveals osmotic stress may be a key factor in delayed neurodegeneration after a cerebral ischemic insult and highlights the significant potential of chemically specific XFI to study the role of taurine in brain disease.« less

Wavelet analysis of birefringence images of myocardium tissue

NASA Astrophysics Data System (ADS)

Sakhnovskiy, M. Yu.; Ushenko, Yu. O.; Kushnerik, L.; Soltys, I. V.; Pavlyukovich, N.; Pavlyukovich, O.

2018-01-01

The paper consists of two parts. The first part presents short theoretical basics of the method of azimuthally-invariant Mueller-matrix description of optical anisotropy of biological tissues. It was provided experimentally measured coordinate distributions of Mueller-matrix invariants (MMI) of linear and circular birefringences of skeletal muscle tissue. It was defined the values of statistic moments, which characterize the distributions of amplitudes of wavelet coefficients of MMI at different scales of scanning. The second part presents the data of statistic analysis of the distributions of amplitude of wavelet coefficients of the distributions of linear birefringence of myocardium tissue died after the infarction and ischemic heart disease. It was defined the objective criteria of differentiation of the cause of death.

The estimation of 3D SAR distributions in the human head from mobile phone compliance testing data for epidemiological studies

NASA Astrophysics Data System (ADS)

Wake, Kanako; Varsier, Nadège; Watanabe, Soichi; Taki, Masao; Wiart, Joe; Mann, Simon; Deltour, Isabelle; Cardis, Elisabeth

2009-10-01

A worldwide epidemiological study called 'INTERPHONE' has been conducted to estimate the hypothetical relationship between brain tumors and mobile phone use. In this study, we proposed a method to estimate 3D distribution of the specific absorption rate (SAR) in the human head due to mobile phone use to provide the exposure gradient for epidemiological studies. 3D SAR distributions due to exposure to an electromagnetic field from mobile phones are estimated from mobile phone compliance testing data for actual devices. The data for compliance testing are measured only on the surface in the region near the device and in a small 3D region around the maximum on the surface in a homogeneous phantom with a specific shape. The method includes an interpolation/extrapolation and a head shape conversion. With the interpolation/extrapolation, SAR distributions in the whole head are estimated from the limited measured data. 3D SAR distributions in the numerical head models, where the tumor location is identified in the epidemiological studies, are obtained from measured SAR data with the head shape conversion by projection. Validation of the proposed method was performed experimentally and numerically. It was confirmed that the proposed method provided good estimation of 3D SAR distribution in the head, especially in the brain, which is the tissue of major interest in epidemiological studies. We conclude that it is possible to estimate 3D SAR distributions in a realistic head model from the data obtained by compliance testing measurements to provide a measure for the exposure gradient in specific locations of the brain for the purpose of exposure assessment in epidemiological studies. The proposed method has been used in several studies in the INTERPHONE.

The estimation of 3D SAR distributions in the human head from mobile phone compliance testing data for epidemiological studies.

PubMed

Wake, Kanako; Varsier, Nadège; Watanabe, Soichi; Taki, Masao; Wiart, Joe; Mann, Simon; Deltour, Isabelle; Cardis, Elisabeth

2009-10-07

A worldwide epidemiological study called 'INTERPHONE' has been conducted to estimate the hypothetical relationship between brain tumors and mobile phone use. In this study, we proposed a method to estimate 3D distribution of the specific absorption rate (SAR) in the human head due to mobile phone use to provide the exposure gradient for epidemiological studies. 3D SAR distributions due to exposure to an electromagnetic field from mobile phones are estimated from mobile phone compliance testing data for actual devices. The data for compliance testing are measured only on the surface in the region near the device and in a small 3D region around the maximum on the surface in a homogeneous phantom with a specific shape. The method includes an interpolation/extrapolation and a head shape conversion. With the interpolation/extrapolation, SAR distributions in the whole head are estimated from the limited measured data. 3D SAR distributions in the numerical head models, where the tumor location is identified in the epidemiological studies, are obtained from measured SAR data with the head shape conversion by projection. Validation of the proposed method was performed experimentally and numerically. It was confirmed that the proposed method provided good estimation of 3D SAR distribution in the head, especially in the brain, which is the tissue of major interest in epidemiological studies. We conclude that it is possible to estimate 3D SAR distributions in a realistic head model from the data obtained by compliance testing measurements to provide a measure for the exposure gradient in specific locations of the brain for the purpose of exposure assessment in epidemiological studies. The proposed method has been used in several studies in the INTERPHONE.

[Expression and distribution of xenoantigen alpha-Gal in intervertebral disk of Chinese banna minipig inbred line].

PubMed

Shou, Jian-guo; Mi, Jian-hong; Ying, Da-jun

2002-09-01

To investigate the expression and distribution of xenoantigen in intervertebral disk of Chinese banna minipig inbred line, and to study the availability of xenograft transplantation of intervertebral disk. Samples of intervertebral disk were collected from six Banna pigs of 8 to 11-month-old. The fixation, embedment and slice were performed. alpha-Gal specific binding lection (BSI-B4) were used as affinity reagents and affinity-immunohistochemistry assays (SABC methods and DAB stain) were conducted to detect the expression and distribution of xenoantigen (alpha-Gal). alpha-Gal was found in chondrocyte cell and chondrocyte-like cell in intervertebral disk which have the positive yellow-stained particulate aggradation. There was no stain in the matrix, elastic fiber and collagen fiber. The distribution of xenoantigen is locally in the tissue of intervertebral disk and its expression is weak. This suggests that the intervertebral disk of Banna pig may be alternative donor for xenotransplantation.

Interrogating the relationship between rat in vivo tissue distribution and drug property data for >200 structurally unrelated molecules

PubMed Central

Harrell, Andrew W; Sychterz, Caroline; Ho, May Y; Weber, Andrew; Valko, Klara; Negash, Kitaw

2015-01-01

The ability to explain distribution patterns from drug physicochemical properties and binding characteristics has been explored for more than 200 compounds by interrogating data from quantitative whole body autoradiography studies (QWBA). These in vivo outcomes have been compared to in silico and in vitro drug property data to determine the most influential properties governing drug distribution. Consistent with current knowledge, in vivo distribution was most influenced by ionization state and lipophilicity which in turn affected phospholipid and plasma protein binding. Basic and neutral molecules were generally better distributed than acidic counterparts demonstrating weaker plasma protein and stronger phospholipid binding. The influence of phospholipid binding was particularly evident in tissues with high phospholipid content like spleen and lung. Conversely, poorer distribution of acidic drugs was associated with stronger plasma protein and weaker phospholipid binding. The distribution of a proportion of acidic drugs was enhanced, however, in tissues known to express anionic uptake transporters such as the liver and kidney. Greatest distribution was observed into melanin containing tissues of the eye, most likely due to melanin binding. Basic molecules were consistently better distributed into parts of the eye and skin containing melanin than those without. The data, therefore, suggest that drug binding to macromolecules strongly influences the distribution of total drug for a large proportion of molecules in most tissues. Reducing lipophilicity, a strategy often used in discovery to optimize pharmacokinetic properties such as absorption and clearance, also decreased the influence of nonspecific binding on drug distribution. PMID:26516585

The evolution and expression of the snaR family of small non-coding RNAs

PubMed Central

Parrott, Andrew M.; Tsai, Michael; Batchu, Priyanka; Ryan, Karen; Ozer, Harvey L.; Tian, Bin; Mathews, Michael B.

2011-01-01

We recently identified the snaR family of small non-coding RNAs that associate in vivo with the nuclear factor 90 (NF90/ILF3) protein. The major human species, snaR-A, is an RNA polymerase III transcript with restricted tissue distribution and orthologs in chimpanzee but not rhesus macaque or mouse. We report their expression in human tissues and their evolution in primates. snaR genes are exclusively in African Great Apes and some are unique to humans. Two novel families of snaR-related genetic elements were found in primates: CAS (catarrhine ancestor of snaR), limited to Old World Monkeys and apes; and ASR (Alu/snaR-related), present in all monkeys and apes. ASR and CAS appear to have spread by retrotransposition, whereas most snaR genes have spread by segmental duplication. snaR-A and snaR-G2 are differentially expressed in discrete regions of the human brain and other tissues, notably including testis. snaR-A is up-regulated in transformed and immortalized human cells, and is stably bound to ribosomes in HeLa cells. We infer that snaR evolved from the left monomer of the primate-specific Alu SINE family via ASR and CAS in conjunction with major primate speciation events, and suggest that snaRs participate in tissue- and species-specific regulation of cell growth and translation. PMID:20935053

Tissue-specific concentrations and patterns of perfluoroalkyl carboxylates and sulfonates in East Greenland polar bears.

PubMed

Greaves, Alana K; Letcher, Robert J; Sonne, Christian; Dietz, Rune; Born, Erik W

2012-11-06

Several perfluoroalkyl carboxylates (PFCAs) and perfluoroalkyl sulfonates (PFSAs) of varying chain length are bioaccumulative in biota. However, wildlife reports have focused on liver and with very little examination of other tissues, and thus there is a limited understanding of their distribution and potential effects in the mammalian body. In the present study, the comparative accumulation of C(6) to C(15) PFCAs, C(4), C(6), C(8) and C(10) PFSAs, and select precursors were examined in the liver, blood, muscle, adipose, and brain of 20 polar bears (Ursus maritimus) from Scoresby Sound, Central East Greenland. Overall, PFSA and PFCA concentrations were highest in liver followed by blood > brain > muscle ≈ adipose. Liver and blood samples contained proportionally more of the shorter/medium chain length (C(6) to C(11)) PFCAs, whereas adipose and brain samples were dominated by longer chain (C(13) to C(15)) PFCAs. PFCAs with lower lipophilicities accumulated more in the liver, whereas the brain accumulated PFCAs with higher lipophilicities. The concentration ratios (±SE) between perfluorooctane sulfonate and its precursor perfluorooctane sulfonamide varied among tissues from 9 (±1):1 (muscle) to 36 (±7):1 (liver). PFCA and PFSA patterns in polar bears indicate that the pharmacokinetics of these compounds are to some extent tissue-specific, and are the result of several factors that may include differing protein interactions throughout the body.

Functional characterization of enzymes catalyzing ceramide phosphoethanolamine biosynthesis in mice.

PubMed

Bickert, Andreas; Ginkel, Christina; Kol, Matthijs; vom Dorp, Katharina; Jastrow, Holger; Degen, Joachim; Jacobs, René L; Vance, Dennis E; Winterhager, Elke; Jiang, Xian-Cheng; Dörmann, Peter; Somerharju, Pentti; Holthuis, Joost C M; Willecke, Klaus

2015-04-01

Besides bulk amounts of SM, mammalian cells produce small quantities of the SM analog ceramide phosphoethanolamine (CPE). Little is known about the biological role of CPE or enzymes responsible for CPE production. Heterologous expression studies revealed that SM synthase (SMS)2 is a bifunctional enzyme producing both SM and CPE, whereas SMS-related protein (SMSr) serves as monofunctional CPE synthase. Acute disruption of SMSr catalytic activity in cultured cells causes a rise in endoplasmic reticulum (ER) ceramides, fragmentation of ER exit sites, and induction of mitochondrial apoptosis. To address the relevance of CPE biosynthesis in vivo, we analyzed the tissue-specific distribution of CPE in mice and generated mouse lines lacking SMSr and SMS2 catalytic activity. We found that CPE levels were >300-fold lower than SM in all tissues examined. Unexpectedly, combined inactivation of SMSr and SMS2 significantly reduced, but did not eliminate, tissue-specific CPE pools and had no obvious impact on mouse development or fertility. While SMSr is widely expressed and serves as the principal CPE synthase in the brain, blocking its catalytic activity did not affect ceramide levels or secretory pathway integrity in the brain or any other tissue. Our data provide a first inventory of CPE species and CPE-biosynthetic enzymes in mammals. Copyright © 2015 by the American Society for Biochemistry and Molecular Biology, Inc.

Ultrasonic technique for imaging tissue vibrations: preliminary results.

PubMed

Sikdar, Siddhartha; Beach, Kirk W; Vaezy, Shahram; Kim, Yongmin

2005-02-01

We propose an ultrasound (US)-based technique for imaging vibrations in the blood vessel walls and surrounding tissue caused by eddies produced during flow through narrowed or punctured arteries. Our approach is to utilize the clutter signal, normally suppressed in conventional color flow imaging, to detect and characterize local tissue vibrations. We demonstrate the feasibility of visualizing the origin and extent of vibrations relative to the underlying anatomy and blood flow in real-time and their quantitative assessment, including measurements of the amplitude, frequency and spatial distribution. We present two signal-processing algorithms, one based on phase decomposition and the other based on spectral estimation using eigen decomposition for isolating vibrations from clutter, blood flow and noise using an ensemble of US echoes. In simulation studies, the computationally efficient phase-decomposition method achieved 96% sensitivity and 98% specificity for vibration detection and was robust to broadband vibrations. Somewhat higher sensitivity (98%) and specificity (99%) could be achieved using the more computationally intensive eigen decomposition-based algorithm. Vibration amplitudes as low as 1 mum were measured accurately in phantom experiments. Real-time tissue vibration imaging at typical color-flow frame rates was implemented on a software-programmable US system. Vibrations were studied in vivo in a stenosed femoral bypass vein graft in a human subject and in a punctured femoral artery and incised spleen in an animal model.

Three isozymes of peptidylarginine deiminase in the chicken: molecular cloning, characterization, and tissue distribution.

PubMed

Shimizu, Akira; Handa, Kenji; Honda, Tomonori; Abe, Naoki; Kojima, Toshio; Takahara, Hidenari

2014-01-01

Peptidylarginine deiminase (PAD; EC 3.5.3.15) is a post-translational modification enzyme that catalyzes the conversion of protein-bound arginine to citrulline (deimination) in a calcium ion dependent manner. Although PADI genes are widely conserved among vertebrates, their function in the chicken is poorly understood. Here, we cloned and sequenced three chicken PADI cDNAs and analyzed the expression of their proteins in various tissues. Immunoblotting analysis showed that chicken PAD1 and PAD3 were present in cells of several central neuron system tissues including the retina; the chicken PAD2 protein was not detected in any tissue. We expressed recombinant chicken PADs in insect cells and characterized their enzymatic properties. The chicken PAD1 and PAD3 recombinant proteins required calcium ions as an essential cofactor for their catalytic activity. The two recombinant proteins showed similar substrate specificities toward synthetic arginine derivatives. By contrast to them, chicken PAD2 did not show any activity. We found that one of the conserved active centers in mammalian PADs had been altered in chicken PAD2; we prepared a reverse mutant but we did not detect an activity. We conclude that chicken PAD1 and PAD3 might play specific roles in the nervous system, but that chicken PAD2 might not be functional under normal physiological conditions. © 2013 Elsevier Inc. All rights reserved.

Rectal Delivery of a DNAzyme That Specifically Blocks the Transcription Factor GATA3 and Reduces Colitis in Mice.

PubMed

Popp, Vanessa; Gerlach, Katharina; Mott, Stefanie; Turowska, Agnieszka; Garn, Holger; Atreya, Raja; Lehr, Hans-Anton; Ho, I-Cheng; Renz, Harald; Weigmann, Benno; Neurath, Markus F

2017-01-01

GATA3 is a transcription factor that regulates T-cell production of cytokines. We investigated the role of GATA3 in development of colitis in mice. We performed quantitative polymerase chain reaction and immunofluorescence analyses of colon tissues from patients with Crohn's disease (n = 61) or ulcerative colitis (UC, n = 74) or from patients without inflammatory bowel diseases (n = 22), to measure levels of GATA3. Colitis was induced by administration of oxazolone or 2,4,6-trinitrobenzenesulfonic acid to control mice, mice with T-cell-specific deletion of GATA3, and mice with deletion of tumor necrosis factor receptor (TNFR) 1 and TNFR2 (TNFR double knockouts); some mice were given a GATA3-specific DNAzyme (hgd40) or a control DNAzyme via intrarectal administration, or systemic injections of an antibody to TNF before or during sensitization and challenge phase of colitis induction. Colon tissues were collected and immunofluorescence and histochemical analyses were performed. Lamina propria mononuclear cells and T cells were isolated and analyzed by flow cytometry or cytokine assays. Colonic distribution of labeled DNAzyme and inflammation were monitored by in vivo imaging (endoscopy) of mice. Levels of GATA3 messenger RNA were higher in colon tissues from patients with UC, but not ileal Crohn's disease, than control tissues; levels of GATA3 correlated with levels of inflammatory cytokines (interleukin [IL] 9, IL17A, IL6, IL5, IL4, IL13, and TNF). We observed increased expression of GATA3 by lamina propria T cells from mice with colitis compared with controls. Mice with T-cell-specific deletion of GATA3 did not develop colitis and their colonic tissues did not produce inflammatory cytokines (IL6, IL9, or IL13). The DNAzyme hgd40 inhibited expression of GATA3 messenger RNA by unstimulated and stimulated T cells, and distributed throughout the inflamed colons of mice with colitis. Colon tissues from mice given hgd40 had reduced expression of GATA3 messenger RNA, compared with mice given a control DNAzyme. Mice given hgd40 did not develop colitis after administration of oxazolone or 2,4,6-trinitrobenzenesulfonic acid; lamina propria cells from these mice expressed lower levels of IL6, IL9, and IL13 than cells from mice given the control DNAzyme. Mini-endoscopic images revealed that hgd40 and anti-TNF reduced colon inflammation over 3 days; hgd40 reduced colitis in TNFR double-knockout mice. Levels of GATA3 are increased in patients with UC and correlate with production of inflammatory cytokines in mice and humans. A DNAzyme that prevents expression of GATA3 reduces colitis in mice, independently of TNF, and reduces levels of cytokines in the colon. This DNAzyme might be developed for treatment of patients with UC. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

Mixed-reproductive strategies, competitive mating-type distribution and life cycle of fourteen black morel species.

PubMed

Du, Xi-Hui; Zhao, Qi; Xia, En-Hua; Gao, Li-Zhi; Richard, Franck; Yang, Zhu L

2017-05-04

Morchella species are well known world-round as popular and prized edible fungi due to their unique culinary flavor. Recently, several species have been successfully cultivated in China. However, their reproductive modes are still unknown, and their basic biology needs to be elucidated. Here, we use the morel genome information to investigate mating systems and life cycles of fourteen black morel species. Mating type-specific primers were developed to screen and genotype ascospores, hymenia and stipes from 223 ascocarps of the 14 species from Asia and Europe. Our data indicated that they are all heterothallic and their life cycles are predominantly haploid, but sterile haploid fruiting also exists. Ascospores in all species are mostly haploid, homokaryotic, and multinuclear, whereas aborted ascospores without any nuclei were also detected. Interestingly, we monitored divergent spatial distribution of both mating types in natural morel populations and cultivated sites, where the fertile tissue of fruiting bodies usually harbored both mating types, whereas sterile tissue of wild morels constantly had one MAT allele, while the sterile tissue of cultivated strains always exhibited both MAT alleles. Furthermore, MAT1-1-1 was detected significantly more commonly than MAT1-2-1 in natural populations, which strongly suggested a competitive advantage for MAT1-1 strains.

Contribution of High Charge and Energy (HZE) Ions During Solar-Particle Event of September 29, 1989

NASA Technical Reports Server (NTRS)

Kim, Myung-Hee Y.; Wilson, John W.; Cucinotta, Francis A.; Simonsen, Lisa C.; Atwell, William; Badavi, Francis F.; Miller, Jack

1999-01-01

The solar-particle event (SPE) of September 29, 1989, produced an iron-rich spectrum with energies approaching 1 A GeV with an approximate spectral slope parameter of 2.5. These high charge and energy (HZE) ions challenge conventional methods of shield design and assessment of astronaut risks. In the past, shield design and risk assessment have relied on proton shielding codes and biological response models derived from X-ray and neutron exposure data. Because the HZE spectra decline rapidly with energy and HZE attenuation in materials is limited by their penetration power, details of the mass distributions about the sensitive tissues (shielding materials and the astronaut's body) are important determining factors of the exposure levels and distributions of linear energy transfer. Local tissue environments during the SPE of September 29, 1989, with its f= components are examined to analyze the importance of these ions to human SPE exposure. Typical space suit and lightly shielded structures leave significant contributions from HZE components to certain critical body tissues and have important implications on the models for risk assessment. A heavily shielded equipment room of a space vehicle or habitat requires knowledge of the breakup of these ions into lighter components, including neutrons, for shield design specifications.

Structure-mechanics relationships in mineralized tendons.

PubMed

Spiesz, Ewa M; Zysset, Philippe K

2015-12-01

In this paper, we review the hierarchical structure and the resulting elastic properties of mineralized tendons as obtained by various multiscale experimental and computational methods spanning from nano- to macroscale. The mechanical properties of mineralized collagen fibres are important to understand the mechanics of hard tissues constituted by complex arrangements of these fibres, like in human lamellar bone. The uniaxial mineralized collagen fibre array naturally occurring in avian tendons is a well studied model tissue for investigating various stages of tissue mineralization and the corresponding elastic properties. Some avian tendons mineralize with maturation, which results in a graded structure containing two zones of distinct morphology, circumferential and interstitial. These zones exhibit different amounts of mineral, collagen, pores and a different mineral distribution between collagen fibrillar and extrafibrillar space that lead to distinct elastic properties. Mineralized tendon cells have two phenotypes: elongated tenocytes placed between fibres in the circumferential zone and cuboidal cells with lower aspect ratios in the interstitial zone. Interestingly some regions of avian tendons seem to be predestined to mineralization, which is exhibited as specific collagen cross-linking patterns as well as distribution of minor tendon constituents (like proteoglycans) and loss of collagen crimp. Results of investigations in naturally mineralizing avian tendons may be useful in understanding the pathological mineralization occurring in some human tendons. Copyright © 2015 Elsevier Ltd. All rights reserved.

Measurement of subcutaneous adipose tissue development in children by the optical device LIPOMETER

NASA Astrophysics Data System (ADS)

Moeller, Reinhard; Horejsi, Renate; Sudi, Karl; Berg, Aloys; Reibnegger, Gilbert; Tafeit, Erwin

2001-10-01

The new optical device LIPOMETER enables the non-invasive, quick and save determination of the thickness of subcutantous adipose tissue (SAT) layers (in nm) at any site of the human body. The topographic specification of 15 evenly distributed body sites allows the precise measurement of subcutaneous body fat distribution, so called subcutaneous adipose tissue topopgraphy (SAT-Top). SAT-Top was determined in more than 1000 children aging from 7 to 21 yr. We describe the SAT-Top development of these subjects through different age groups and the differences between male and female SAT-Top development in each age group. SAT layer profiles (medians of the 15 body sites) for boys and girls in age group (7-9 yr) show a very similar pattern for both sexes, followed by decreasing SAT layer thicknesses in boys and increasing values in girls in the subsequent age groups. Between age group 3 (11-13 yr) and age group 7 (19- 21 yr) male and female SAT-Top is significantly different in (almost) all body sites. We present a precise description of SAT-Top development in boys and girls, providing a basis for further investigations in different fields such as obesity, sport sciences or metabolic disorders, and suggesting the LIPOMETER technique as an appropriate measurement tool.

A Nanostructured Matrices Assessment to Study Drug Distribution in Solid Tumor Tissues by Mass Spectrometry Imaging

PubMed Central

Giordano, Silvia; Pifferi, Valentina; Morosi, Lavinia; Morelli, Melinda; Falciola, Luigi; Cappelletti, Giuseppe; Visentin, Sonja; Licandro, Simonetta A.; Frapolli, Roberta; Zucchetti, Massimo; Pastorelli, Roberta; Brunelli, Laura; D’Incalci, Maurizio; Davoli, Enrico

2017-01-01

The imaging of drugs inside tissues is pivotal in oncology to assess whether a drug reaches all cells in an adequate enough concentration to eradicate the tumor. Matrix-Assisted Laser Desorption Ionization Mass Spectrometry Imaging (MALDI-MSI) is one of the most promising imaging techniques that enables the simultaneous visualization of multiple compounds inside tissues. The choice of a suitable matrix constitutes a critical aspect during the development of a MALDI-MSI protocol since the matrix ionization efficiency changes depending on the analyte structure and its physico-chemical properties. The objective of this study is the improvement of the MALDI-MSI technique in the field of pharmacology; developing specifically designed nanostructured surfaces that allow the imaging of different drugs with high sensitivity and reproducibility. Among several nanomaterials, we tested the behavior of gold and titanium nanoparticles, and halloysites and carbon nanotubes as possible matrices. All nanomaterials were firstly screened by co-spotting them with drugs on a MALDI plate, evaluating the drug signal intensity and the signal-to-noise ratio. The best performing matrices were tested on control tumor slices, and were spotted with drugs to check the ion suppression effect of the biological matrix. Finally; the best nanomaterials were employed in a preliminary drug distribution study inside tumors from treated mice. PMID:28336905

Cationic Contrast Agent Diffusion Differs Between Cartilage and Meniscus.

PubMed

Honkanen, Juuso T J; Turunen, Mikael J; Freedman, Jonathan D; Saarakkala, Simo; Grinstaff, Mark W; Ylärinne, Janne H; Jurvelin, Jukka S; Töyräs, Juha

2016-10-01

Contrast enhanced computed tomography (CECT) is a non-destructive imaging technique used for the assessment of composition and structure of articular cartilage and meniscus. Due to structural and compositional differences between these tissues, diffusion and distribution of contrast agents may differ in cartilage and meniscus. The aim of this study is to determine the diffusion kinematics of a novel iodine based cationic contrast agent (CA(2+)) in cartilage and meniscus. Cylindrical cartilage and meniscus samples (d = 6 mm, h ≈ 2 mm) were harvested from healthy bovine knee joints (n = 10), immersed in isotonic cationic contrast agent (20 mgI/mL), and imaged using a micro-CT scanner at 26 time points up to 48 h. Subsequently, normalized X-ray attenuation and contrast agent diffusion flux, as well as water, collagen and proteoglycan (PG) contents in the tissues were determined. The contrast agent distributions within cartilage and meniscus were different. In addition, the normalized attenuation and diffusion flux were higher (p < 0.05) in cartilage. Based on these results, diffusion kinematics vary between cartilage and meniscus. These tissue specific variations can affect the interpretation of CECT images and should be considered when cartilage and meniscus are assessed simultaneously.

Quantitative evaluation of mucosal vascular contrast in narrow band imaging using Monte Carlo modeling

NASA Astrophysics Data System (ADS)

Le, Du; Wang, Quanzeng; Ramella-Roman, Jessica; Pfefer, Joshua

2012-06-01

Narrow-band imaging (NBI) is a spectrally-selective reflectance imaging technique for enhanced visualization of superficial vasculature. Prior clinical studies have indicated NBI's potential for detection of vasculature abnormalities associated with gastrointestinal mucosal neoplasia. While the basic mechanisms behind the increased vessel contrast - hemoglobin absorption and tissue scattering - are known, a quantitative understanding of the effect of tissue and device parameters has not been achieved. In this investigation, we developed and implemented a numerical model of light propagation that simulates NBI reflectance distributions. This was accomplished by incorporating mucosal tissue layers and vessel-like structures in a voxel-based Monte Carlo algorithm. Epithelial and mucosal layers as well as blood vessels were defined using wavelength-specific optical properties. The model was implemented to calculate reflectance distributions and vessel contrast values as a function of vessel depth (0.05 to 0.50 mm) and diameter (0.01 to 0.10 mm). These relationships were determined for NBI wavelengths of 410 nm and 540 nm, as well as broadband illumination common to standard endoscopic imaging. The effects of illumination bandwidth on vessel contrast were also simulated. Our results provide a quantitative analysis of the effect of absorption and scattering on vessel contrast. Additional insights and potential approaches for improving NBI system contrast are discussed.

Tissue- and Cell-Specific Cytokinin Activity in Populus × canescens Monitored by ARR5::GUS Reporter Lines in Summer and Winter.

PubMed

Paul, Shanty; Wildhagen, Henning; Janz, Dennis; Teichmann, Thomas; Hänsch, Robert; Polle, Andrea

2016-01-01

Cytokinins play an important role in vascular development. But knowledge on the cellular localization of this growth hormone in the stem and other organs of woody plants is lacking. The main focus of this study was to investigate the occurrence and cellular localization of active cytokinins in leaves, roots, and along the stem of Populus × canescens and to find out how the pattern is changed between summer and winter. An ARR5::GUS reporter construct was used to monitor distribution of active cytokinins in different tissues of transgenic poplar lines. Three transgenic lines tested under outdoor conditions showed no influence of ARR5::GUS reporter construct on the growth performance compared with the wild-type, but one line lost the reporter activity. ARR5::GUS activity indicated changes in the tissue- and cell type-specific pattern of cytokinin activity during dormancy compared with the growth phase. ARR5::GUS activity, which was present in the root tips in the growing season, disappeared in winter. In the stem apex ground tissue, ARR5::GUS activity was higher in winter than in summer. Immature leaves from tissue-culture grown plants showed inducible ARR5::GUS activity. Leaf primordia in summer showed ARR5::GUS activity, but not the expanded leaves of outdoor plants or leaf primordia in winter. In stem cross sections, the most prominent ARR5::GUS activity was detected in the cortex region and in the rays of bark in summer and in winter. In the cambial zone the ARR5::GUS activity was more pronounced in the dormant than in growth phase. The pith and the ray cells adjacent to the vessels also displayed ARR5::GUS activity. In silico analyses of the tissue-specific expression patterns of the whole PtRR type-A family of poplar showed that PtRR10, the closest ortholog to the Arabidopsis ARR5 gene, was usually the most highly expressed gene in all tissues. In conclusion, gene expression and tissue-localization indicate high activity of cytokinins not only in summer, but also in winter. The presence of the signal in meristematic tissues supports their role in meristem maintenance. The reporter lines will be useful to study the involvement of cytokinins in acclimation of poplar growth to stress.

[Project to enhance bone bank tissue storage and distribution procedures].

PubMed

Huang, Jui-Chen; Wu, Chiung-Lan; Chen, Chun-Chuan; Chen, Shu-Hua

2011-10-01

Organ and tissue transplantation are now commonly preformed procedures. Improper organ bank handling procedures may increase infection risks. Execution accuracy in terms of tissue storage and distribution at our bone bank was 80%. We thus proposed an execution improvement project to enhance procedures in order to fulfill the intent of donors and ensure recipient safety. This project was designed to raise nurse professionalism, and ensure patient safety through enhanced tissue storage and distribution procedures. Education programs developed for this project focus on teaching standard operating procedures for bone and ligament storage and distribution, bone bank facility maintenance, trouble shooting and solutions, and periodic inspection systems. Cognition of proper storage and distribution procedures rose from 81% to 100%; Execution accuracy also rose from 80% to 100%. The project successfully conveyed concepts essential to the correct execution of organ storage and distribution procedures and proper organ bank facility management. Achieving and maintaining procedural and management standards is crucial to continued organ donations and the recipient safety.

Bioaccumulation and tissue distribution of antibiotics in wild marine fish from Laizhou Bay, North China.

PubMed

Liu, Sisi; Bekele, Tadiyose-Girma; Zhao, Hongxia; Cai, Xiyun; Chen, Jingwen

2018-08-01

Information about bioaccumulation and tissue distribution of antibiotics in wild marine fish is still limited. In the present study, tissue levels, bioaccumulation and distribution patterns of 9 sulfonamide (SA), trimethoprim (TMP), 5 fluoroquinolone (FQ), and 4 macrolide (ML) antibiotics were investigated in gill, muscle, kidney, and liver tissues of seven wild fish species collected from Laizhou Bay, North China in 2016. All the 19 antibiotics were detected in these fish tissues with the total concentrations ranging from 22ng/g dry weight (dw) to 500ng/g dw. The mean values of logarithm bioaccumulation factors (BAFs) in the gills, muscles, kidneys, and livers ranged from 2.2 to 4.8, 1.9 to 4.0, 2.5 to 4.9, and 2.5 to 5.4, respectively. Log BAFs of antibiotics in these tissues significantly increased (r=0.61-0.77, p<0.001) with their logarithm values of liposome-water distribution coefficient (D lipw ) except in the muscles, suggesting that D lipw can well assess the bioaccumulation potentials of antibiotics in phospholipid-rich tissues. In general, the SAs, TMP, and FQs were primarily accumulated in the muscles and the MLs were primarily in the livers, which may be related to their toxicokinetic processes of these marine fish. The present study for the first time reported the tissue distribution patterns of antibiotics in wild marine fish. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of microvascular distribution and its density on interstitial fluid pressure in solid tumors: A computational model.

PubMed

Mohammadi, M; Chen, P

2015-09-01

Solid tumors with different microvascular densities (MVD) have been shown to have different outcomes in clinical studies. Other studies have demonstrated the significant correlation between high MVD, elevated interstitial fluid pressure (IFP) and metastasis in cancers. Elevated IFP in solid tumors prevents drug macromolecules reaching most cancerous cells. To overcome this barrier, antiangiogenesis drugs can reduce MVD within the tumor and lower IFP. A quantitative approach is essential to compute how much reduction in MVD is required for a specific tumor to reach a desired amount of IFP for drug delivery purposes. Here we provide a computational framework to investigate how IFP is affected by the tumor size, the MVD, and location of vessels within the tumor. A general physiologically relevant tumor type with a heterogenous vascular structure surrounded by normal tissue is utilized. Then the continuity equation, Darcy's law, and Starling's equation are applied in the continuum mechanics model, which can calculate IFP for different cases of solid tumors. High MVD causes IFP elevation in solid tumors, and IFP distribution correlates with microvascular distribution within tumor tissue. However, for tumors with constant MVD but different microvascular structures, the average values of IFP were found to be the same. Moreover, for a constant MVD and vascular distribution, an increase in tumor size leads to increased IFP. Copyright © 2015 Elsevier Inc. All rights reserved.

Synchrotron micro-scale measurement of metal distributions in Phragmites australis and Typha latifolia root tissue from an urban brownfield site

DOE PAGES

Feng, Huan; Qian, Yu; Gallagher, Frank J.; ...

2015-11-01

Liberty State Park in New Jersey, USA, is a “brownfield” site containing various levels of contaminants. To investigate metal uptake and distributions in plants on the brownfield site, Phragmites australis and Typha latifolia were collected in Liberty State Park during the growing season (May–September) in 2011 at two sites with the high and low metal loads, respectively. The objective of this study was to understand the metal (Fe, Mn, Cu, Pb and Zn) concentration and spatial distributions in P. australis and T. latifolia root systems with micro-meter scale resolution using synchrotron X-ray microfluorescence (μXRF) and synchrotron X-ray computed microtomography (μCMT)more » techniques. The root structure measurement by synchrotron μCMT showed that high X-ray attenuation substance appeared in the epidermis. Synchrotron μXRF measurement showed that metal concentrations and distributions in the root cross-section between epidermis and vascular tissue were statistically different. Significant correlations were found between metals (Cu, Mn, Pb and Zn) and Fe in the epidermis, implying that metals were scavenged by Fe oxides. The results from this study suggest that the expression of metal transport and accumulation within the root systems may be element specific. The information derived from this study can improve our current knowledge of the wetland plant ecological function in brownfield remediation.« less

Toward a unified model of passive drug permeation II: the physiochemical determinants of unbound tissue distribution with applications to the design of hepatoselective glucokinase activators.

PubMed

Ghosh, Avijit; Maurer, Tristan S; Litchfield, John; Varma, Manthema V; Rotter, Charles; Scialis, Renato; Feng, Bo; Tu, Meihua; Guimaraes, Cris R W; Scott, Dennis O

2014-10-01

In this work, we leverage a mathematical model of the underlying physiochemical properties of tissues and physicochemical properties of molecules to support the development of hepatoselective glucokinase activators. Passive distribution is modeled via a Fick-Nernst-Planck approach, using in vitro experimental data to estimate the permeability of both ionized and neutral species. The model accounts for pH and electrochemical potential across cellular membranes, ionization according to Henderson-Hasselbalch, passive permeation of the neutral species using Fick's law, and passive permeation of the ionized species using the Nernst-Planck equation. The mathematical model of the physiochemical system allows derivation of a single set of parameters governing the distribution of drug molecules across multiple conditions both in vitro and in vivo. A case study using this approach in the development of hepatoselective glucokinase activators via organic anion-transporting polypeptide-mediated hepatic uptake and impaired passive distribution to the pancreas is described. The results for these molecules indicate the permeability penalty of the ionized form is offset by its relative abundance, leading to passive pancreatic exclusion according to the Nernst-Planck extension of Fickian passive permeation. Generally, this model serves as a useful construct for drug discovery scientists to understand subcellular exposure of acids or bases using specific physiochemical properties. Copyright © 2014 by The American Society for Pharmacology and Experimental Therapeutics.

Imaging Metals in Brain Tissue by Laser Ablation - Inductively Coupled Plasma - Mass Spectrometry (LA-ICP-MS)

PubMed Central

Hare, Dominic J.; Kysenius, Kai; Paul, Bence; Knauer, Beate; Hutchinson, Robert W.; O'Connor, Ciaran; Fryer, Fred; Hennessey, Tom P.; Bush, Ashley I.; Crouch, Peter J.; Doble, Philip A.

2017-01-01

Metals are found ubiquitously throughout an organism, with their biological role dictated by both their chemical reactivity and abundance within a specific anatomical region. Within the brain, metals have a highly compartmentalized distribution, depending on the primary function they play within the central nervous system. Imaging the spatial distribution of metals has provided unique insight into the biochemical architecture of the brain, allowing direct correlation between neuroanatomical regions and their known function with regard to metal-dependent processes. In addition, several age-related neurological disorders feature disrupted metal homeostasis, which is often confined to small regions of the brain that are otherwise difficult to analyze. Here, we describe a comprehensive method for quantitatively imaging metals in the mouse brain, using laser ablation - inductively coupled plasma - mass spectrometry (LA-ICP-MS) and specially designed image processing software. Focusing on iron, copper and zinc, which are three of the most abundant and disease-relevant metals within the brain, we describe the essential steps in sample preparation, analysis, quantitative measurements and image processing to produce maps of metal distribution within the low micrometer resolution range. This technique, applicable to any cut tissue section, is capable of demonstrating the highly variable distribution of metals within an organ or system, and can be used to identify changes in metal homeostasis and absolute levels within fine anatomical structures. PMID:28190025

Pattern of iron distribution in maternal and filial tissues in wheat grains with contrasting levels of iron.

PubMed

Singh, Sudhir P; Vogel-Mikuš, Katarina; Arčon, Iztok; Vavpetič, Primož; Jeromel, Luka; Pelicon, Primož; Kumar, Jitendra; Tuli, Rakesh

2013-08-01

Iron insufficiency is a worldwide problem in human diets. In cereals like wheat, the bran layer of the grains is an important source of iron. However, the dietary availability of iron in wheat flour is limited due to the loss of the iron-rich bran during milling and processing and the presence of anti-nutrients like phytic acid that keep iron strongly chelated in the grain. The present study investigated the localization of iron and phosphorus in grain tissues of wheat genotypes with contrasting grain iron content using synchrotron-based micro-X-ray fluorescence (micro-XRF) and micro-proton-induced X-ray emission (micro-PIXE). X-ray absorption near-edge spectroscopy (XANES) was employed to determine the proportion of divalent and trivalent forms of Fe in the grains. It revealed the abundance of oxygen, phosphorus, and sulphur in the local chemical environment of Fe in grains, as Fe-O-P-R and Fe-O-S-R coordination. Contrasting differences were noticed in tissue-specific relative localization of Fe, P, and S among the different genotypes, suggesting a possible effect of localization pattern on iron bioavailability. The current study reports the shift in iron distribution from maternal to filial tissues of grains during the evolution of wheat from its wild relatives to the present-day cultivated varieties, and thus suggests the value of detailed physical localization studies in varietal improvement programmes for food crops.

Geometry Design Optimization of Functionally Graded Scaffolds for Bone Tissue Engineering: A Mechanobiological Approach

PubMed Central

Boccaccio, Antonio; Uva, Antonio Emmanuele; Fiorentino, Michele; Mori, Giorgio; Monno, Giuseppe

2016-01-01

Functionally Graded Scaffolds (FGSs) are porous biomaterials where porosity changes in space with a specific gradient. In spite of their wide use in bone tissue engineering, possible models that relate the scaffold gradient to the mechanical and biological requirements for the regeneration of the bony tissue are currently missing. In this study we attempt to bridge the gap by developing a mechanobiology-based optimization algorithm aimed to determine the optimal graded porosity distribution in FGSs. The algorithm combines the parametric finite element model of a FGS, a computational mechano-regulation model and a numerical optimization routine. For assigned boundary and loading conditions, the algorithm builds iteratively different scaffold geometry configurations with different porosity distributions until the best microstructure geometry is reached, i.e. the geometry that allows the amount of bone formation to be maximized. We tested different porosity distribution laws, loading conditions and scaffold Young’s modulus values. For each combination of these variables, the explicit equation of the porosity distribution law–i.e the law that describes the pore dimensions in function of the spatial coordinates–was determined that allows the highest amounts of bone to be generated. The results show that the loading conditions affect significantly the optimal porosity distribution. For a pure compression loading, it was found that the pore dimensions are almost constant throughout the entire scaffold and using a FGS allows the formation of amounts of bone slightly larger than those obtainable with a homogeneous porosity scaffold. For a pure shear loading, instead, FGSs allow to significantly increase the bone formation compared to a homogeneous porosity scaffolds. Although experimental data is still necessary to properly relate the mechanical/biological environment to the scaffold microstructure, this model represents an important step towards optimizing geometry of functionally graded scaffolds based on mechanobiological criteria. PMID:26771746

High-resolution harmonic motion imaging (HR-HMI) for tissue biomechanical property characterization

PubMed Central

Ma, Teng; Qian, Xuejun; Chiu, Chi Tat; Yu, Mingyue; Jung, Hayong; Tung, Yao-Sheng; Shung, K. Kirk

2015-01-01

Background Elastography, capable of mapping the biomechanical properties of biological tissues, serves as a useful technique for clinicians to perform disease diagnosis and determine stages of many diseases. Many acoustic radiation force (ARF) based elastography, including acoustic radiation force impulse (ARFI) imaging and harmonic motion imaging (HMI), have been developed to remotely assess the elastic properties of tissues. However, due to the lower operating frequencies of these approaches, their spatial resolutions are insufficient for revealing stiffness distribution on small scale applications, such as cancerous tumor margin detection, atherosclerotic plaque composition analysis and ophthalmologic tissue characterization. Though recently developed ARF-based optical coherence elastography (OCE) methods open a new window for the high resolution elastography, shallow imaging depths significantly limit their usefulness in clinics. Methods The aim of this study is to develop a high-resolution HMI method to assess the tissue biomechanical properties with acceptable field of view (FOV) using a 4 MHz ring transducer for efficient excitation and a 40 MHz needle transducer for accurate detection. Under precise alignment of two confocal transducers, the high-resolution HMI system has a lateral resolution of 314 µm and an axial resolution of 
147 µm with an effective FOV of 2 mm in depth. Results The performance of this high resolution imaging system was validated on the agar-based tissue mimicking phantoms with different stiffness distributions. These data demonstrated the imaging system’s improved resolution and sensitivity on differentiating materials with varying stiffness. In addition, ex vivo imaging of a human atherosclerosis coronary artery demonstrated the capability of high resolution HMI in identifying layer-specific structures and characterizing atherosclerotic plaques based on their stiffness differences. Conclusions All together high resolution HMI appears to be a promising ultrasound-only technology for characterizing tissue biomechanical properties at the microstructural level to improve the image-based diseases diagnosis in multiple clinical applications. PMID:25694960

High-resolution harmonic motion imaging (HR-HMI) for tissue biomechanical property characterization.

PubMed

Ma, Teng; Qian, Xuejun; Chiu, Chi Tat; Yu, Mingyue; Jung, Hayong; Tung, Yao-Sheng; Shung, K Kirk; Zhou, Qifa

2015-02-01

Elastography, capable of mapping the biomechanical properties of biological tissues, serves as a useful technique for clinicians to perform disease diagnosis and determine stages of many diseases. Many acoustic radiation force (ARF) based elastography, including acoustic radiation force impulse (ARFI) imaging and harmonic motion imaging (HMI), have been developed to remotely assess the elastic properties of tissues. However, due to the lower operating frequencies of these approaches, their spatial resolutions are insufficient for revealing stiffness distribution on small scale applications, such as cancerous tumor margin detection, atherosclerotic plaque composition analysis and ophthalmologic tissue characterization. Though recently developed ARF-based optical coherence elastography (OCE) methods open a new window for the high resolution elastography, shallow imaging depths significantly limit their usefulness in clinics. The aim of this study is to develop a high-resolution HMI method to assess the tissue biomechanical properties with acceptable field of view (FOV) using a 4 MHz ring transducer for efficient excitation and a 40 MHz needle transducer for accurate detection. Under precise alignment of two confocal transducers, the high-resolution HMI system has a lateral resolution of 314 µm and an axial resolution of 
147 µm with an effective FOV of 2 mm in depth. The performance of this high resolution imaging system was validated on the agar-based tissue mimicking phantoms with different stiffness distributions. These data demonstrated the imaging system's improved resolution and sensitivity on differentiating materials with varying stiffness. In addition, ex vivo imaging of a human atherosclerosis coronary artery demonstrated the capability of high resolution HMI in identifying layer-specific structures and characterizing atherosclerotic plaques based on their stiffness differences. All together high resolution HMI appears to be a promising ultrasound-only technology for characterizing tissue biomechanical properties at the microstructural level to improve the image-based diseases diagnosis in multiple clinical applications.

Oral dendritic cells mediate antigen-specific tolerance by stimulating TH1 and regulatory CD4+ T cells.

PubMed

Mascarell, Laurent; Lombardi, Vincent; Louise, Anne; Saint-Lu, Nathalie; Chabre, Henri; Moussu, Hélène; Betbeder, Didier; Balazuc, Anne-Marie; Van Overtvelt, Laurence; Moingeon, Philippe

2008-09-01

A detailed characterization of oral antigen-presenting cells is critical to improve second-generation sublingual allergy vaccines. To characterize oral dendritic cells (DCs) within lingual and buccal tissues from BALB/c mice with respect to their surface phenotype, distribution, and capacity to polarize CD4(+) T-cell responses. In situ analysis of oral DCs was performed by immunohistology. Purified DCs were tested in vitro for their capacity to capture, process, and present the ovalbumin antigen to naive CD4(+) T cells. In vivo priming of ovalbumin-specific T cells adoptively transferred to BALB/c mice was analyzed by cytofluorometry in cervical lymph nodes after sublingual administration of mucoadhesive ovalbumin. Three subsets of oral DCs with a distinct tissue distribution were identified: (1) a minor subset of CD207(+) Langerhans cells located in the mucosa itself, (2) a major subpopulation of CD11b(+)CD11c(-) and CD11b(+)CD11c(+) myeloid DCs at the mucosal/submucosal interface, and (3) B220(+)120G8(+) plasmacytoid DCs found in submucosal tissues. Purified myeloid and plasmacytoid oral DCs capture and process the antigen efficiently and are programmed to elicit IFN-gamma and/or IL-10 production together with a suppressive function in naive CD4(+) T cells. Targeting the ovalbumin antigen to oral DCs in vivo by using mucoadhesive particles establishes tolerance in the absence of cell depletion through the stimulation of IFN-gamma and IL-10-producing CD4(+) regulatory T cells in cervical lymph nodes. The oral immune system is composed of various subsets of tolerogenic DCs organized in a compartmentalized manner and programmed to induce T(H)1/regulatory T-cell responses.

In vivo vitamin C deficiency in guinea pigs increases ascorbate transporters in liver but not kidney and brain.

PubMed

Søgaard, Ditte; Lindblad, Maiken M; Paidi, Maya D; Hasselholt, Stine; Lykkesfeldt, Jens; Tveden-Nyborg, Pernille

2014-07-01

Moderate vitamin C (vitC) deficiency (plasma concentrations less than 23 μmol/L) affects as much as 10% of adults in the Western World and has been associated with an increased mortality in disease complexes such as cardiovascular disease and the metabolic syndrome. The distribution of vitC within the body is subjected to complex and nonlinear pharmacokinetics and largely depends on the sodium-dependent vitC-specific transporters, sodium-dependent vitamin C transporter 1 (SVCT1) and sodium-dependent vitamin C transporter 2 (SVCT2). Although currently not established, it is likely to expect that a state of deficiency may affect the expression of these transporters to preserve vitC concentrations in specific target tissues. We hypothesized that diet-induced states of vitC deficiency lead to alterations in the messenger RNA (mRNA) and/or protein expression of vitC transporters, thereby regulating vitC tissue distribution. Using guinea pigs as a validated model, this study investigated the effects of a diet-induced vitC deficiency (100 mg vitC/kg feed) or depletion (0 mg vitC/kg feed) on the expression of transporters SVCT1 and SVCT2 in selected tissues and the transport from plasma to cerebrospinal fluid (CSF). In deficient animals, SVCT1 was increased in the liver, whereas a decreased SVCT1 expression but increased SVCT2 mRNA in livers of depleted animals suggests a shift in transporter expression as response to the diet. In CSF, a constant plasma:CSF ratio shows unaltered vitC transport irrespective of dietary regime. The study adds novel information to the complex regulation maintaining vitC homeostasis in vivo during states of deficiency. Copyright © 2014 Elsevier Inc. All rights reserved.

Magnetic Resonance Based Electrical Properties Tomography: A Review

PubMed Central

Zhang, Xiaotong; Liu, Jiaen

2014-01-01

Frequency-dependent electrical properties (EPs; conductivity and permittivity) of biological tissues provide important diagnostic information (e.g. tumor characterization), and also play an important role in quantifying radiofrequency (RF) coil induced Specific Absorption Rate (SAR) which is a major safety concern in high- and ultrahigh-field Magnetic Resonance Imaging (MRI) applications. Cross-sectional imaging of EPs has been pursued for decades. Recently introduced Electrical Properties Tomography (EPT) approaches utilize the measurable RF magnetic field induced by the RF coil in an MRI system to quantitatively reconstruct the EP distribution in vivo and non-invasively with a spatial resolution of a few millimeters or less. This paper reviews the Electrical Properties Tomography approach from its basic theory in electromagnetism to the state of the art research outcomes. Emphasizing on the imaging reconstruction methods rather than experimentation techniques, we review the developed imaging algorithms, validation results in physical phantoms and biological tissues, as well as their applications in in vivo tumor detection and subject-specific SAR prediction. Challenges for future research are also discussed. PMID:24803104

Mesoscopic Fluorescence Molecular Tomography for Evaluating Engineered Tissues.

PubMed

Ozturk, Mehmet S; Chen, Chao-Wei; Ji, Robin; Zhao, Lingling; Nguyen, Bao-Ngoc B; Fisher, John P; Chen, Yu; Intes, Xavier

2016-03-01

Optimization of regenerative medicine strategies includes the design of biomaterials, development of cell-seeding methods, and control of cell-biomaterial interactions within the engineered tissues. Among these steps, one paramount challenge is to non-destructively image the engineered tissues in their entirety to assess structure, function, and molecular expression. It is especially important to be able to enable cell phenotyping and monitor the distribution and migration of cells throughout the bulk scaffold. Advanced fluorescence microscopic techniques are commonly employed to perform such tasks; however, they are limited to superficial examination of tissue constructs. Therefore, the field of tissue engineering and regenerative medicine would greatly benefit from the development of molecular imaging techniques which are capable of non-destructive imaging of three-dimensional cellular distribution and maturation within a tissue-engineered scaffold beyond the limited depth of current microscopic techniques. In this review, we focus on an emerging depth-resolved optical mesoscopic imaging technique, termed laminar optical tomography (LOT) or mesoscopic fluorescence molecular tomography (MFMT), which enables longitudinal imaging of cellular distribution in thick tissue engineering constructs at depths of a few millimeters and with relatively high resolution. The physical principle, image formation, and instrumentation of LOT/MFMT systems are introduced. Representative applications in tissue engineering include imaging the distribution of human mesenchymal stem cells embedded in hydrogels, imaging of bio-printed tissues, and in vivo applications.

Oxytocin receptor dynamics in the brain across development and species.

PubMed

Vaidyanathan, Radhika; Hammock, Elizabeth A D

2017-02-01

Oxytocin (OXT) signaling through the OXT receptor plays a significant role in a variety of physiological processes throughout the lifespan. OXT's effects depend on the tissue distribution of the receptor. This tissue specificity is dynamic and changes across development, and also varies with sex, experience, and species. The purpose of this review is to highlight these themes with examples from several life stages and several species. Important knowledge gaps will also be emphasized. Understanding the effective sites of action for OXT via its receptor will help refine hypotheses about the roles of this important neuropeptide in the experience-dependent development and expression of species-typical social behavior. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 143-157, 2017. © 2016 Wiley Periodicals, Inc.

Azimuthally invariant Mueller-matrix mapping of optically anisotropic layers of biological networks of blood plasma in the diagnosis of liver disease

NASA Astrophysics Data System (ADS)

Ushenko, A. G.; Dubolazov, A. V.; Ushenko, V. A.; Ushenko, Yu. A.; Sakhnovskiy, M. Y.; Pavlyukovich, O.; Pavlyukovich, N.; Novakovskaya, O.; Gorsky, M. P.

2016-09-01

The model of Mueller-matrix description of mechanisms of optical anisotropy that typical for polycrystalline layers of the histological sections of biological tissues and fluids - optical activity, birefringence, as well as linear and circular dichroism - is suggested. Within the statistical analysis distributions quantities of linear and circular birefringence and dichroism the objective criteria of differentiation of myocardium histological sections (determining the cause of death); films of blood plasma (liver pathology); peritoneal fluid (endometriosis of tissues of women reproductive sphere); urine (kidney disease) were determined. From the point of view of probative medicine the operational characteristics (sensitivity, specificity and accuracy) of the method of Mueller-matrix reconstruction of optical anisotropy parameters were found.

Transferrin receptors in human tissues: their distribution and possible clinical relevance.

PubMed

Gatter, K C; Brown, G; Trowbridge, I S; Woolston, R E; Mason, D Y

1983-05-01

The distribution of transferrin receptors (TR) has been studied in a range of normal and malignant tissues using four monoclonal antibodies, BK19.9, B3/25, T56/14 and T58/1. In normal tissues TR was found in a limited number of sites, notably basal epidermis, the endocrine pancreas, hepatocytes, Kupffer cells, testis and pituitary. This restricted pattern of distribution may be relevant to the characteristic pattern of iron deposition in primary haemachromatosis. In contrast to this limited pattern of expression in normal tissue, the receptor was widely distributed in carcinomas, sarcomas and in samples from cases of Hodgkin's disease. This malignancy-associated expression of the receptor may play a role in the anaemia of advanced malignancy by competing with the bone marrow for serum iron.

Transferrin receptors in human tissues: their distribution and possible clinical relevance.

PubMed Central

Gatter, K C; Brown, G; Trowbridge, I S; Woolston, R E; Mason, D Y

1983-01-01

The distribution of transferrin receptors (TR) has been studied in a range of normal and malignant tissues using four monoclonal antibodies, BK19.9, B3/25, T56/14 and T58/1. In normal tissues TR was found in a limited number of sites, notably basal epidermis, the endocrine pancreas, hepatocytes, Kupffer cells, testis and pituitary. This restricted pattern of distribution may be relevant to the characteristic pattern of iron deposition in primary haemachromatosis. In contrast to this limited pattern of expression in normal tissue, the receptor was widely distributed in carcinomas, sarcomas and in samples from cases of Hodgkin's disease. This malignancy-associated expression of the receptor may play a role in the anaemia of advanced malignancy by competing with the bone marrow for serum iron. Images PMID:6302135

GhL1L1 affects cell fate specification by regulating GhPIN1-mediated auxin distribution.

PubMed

Xu, Jiao; Yang, Xiyan; Li, Baoqi; Chen, Lin; Min, Ling; Zhang, Xianlong

2018-05-13

Auxin is as an efficient initiator and regulator of cell fate during somatic embryogenesis (SE), but the molecular mechanisms and regulating networks of this process are not well understood. In this report, we analysed SE process induced by Leafy cotyledon1-like 1 (GhL1L1), a NF-YB subfamily gene specifically expressed in embryonic tissues in cotton. We also identified the target gene of GhL1L1, and its role in auxin distribution and cell fate specification during embryonic development was analysed. Overexpression of GhL1L1 accelerated embryonic cell formation, associated with an increased concentration of IAA in embryogenic calluses (ECs) and in the shoot apical meristem (SAM), corresponding to altered expression of the auxin transport gene GhPIN1. By contrast, GhL1L1-deficient explants showed retarded embryonic cell formation, and the concentration of IAA was decreased in GhL1L1-deficient ECs. Disruption of auxin distribution accelerated the specification of embryonic cell fate together with regulation of GhPIN1. Furthermore, we showed that PHOSPHATASE 2AA2 (GhPP2AA2) was activated by GhL1L1 through targeting the G-box of its promoter, hence regulating the activity of GhPIN1 protein. Our results indicate that GhL1L1 functions as a key regulator in auxin distribution to regulate cell fate specification in cotton and contribute to the understanding of the complex process of SE in plant species. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Computational Identification of Tissue-Specific Splicing Regulatory Elements in Human Genes from RNA-Seq Data.

PubMed

Badr, Eman; ElHefnawi, Mahmoud; Heath, Lenwood S

2016-01-01

Alternative splicing is a vital process for regulating gene expression and promoting proteomic diversity. It plays a key role in tissue-specific expressed genes. This specificity is mainly regulated by splicing factors that bind to specific sequences called splicing regulatory elements (SREs). Here, we report a genome-wide analysis to study alternative splicing on multiple tissues, including brain, heart, liver, and muscle. We propose a pipeline to identify differential exons across tissues and hence tissue-specific SREs. In our pipeline, we utilize the DEXSeq package along with our previously reported algorithms. Utilizing the publicly available RNA-Seq data set from the Human BodyMap project, we identified 28,100 differentially used exons across the four tissues. We identified tissue-specific exonic splicing enhancers that overlap with various previously published experimental and computational databases. A complicated exonic enhancer regulatory network was revealed, where multiple exonic enhancers were found across multiple tissues while some were found only in specific tissues. Putative combinatorial exonic enhancers and silencers were discovered as well, which may be responsible for exon inclusion or exclusion across tissues. Some of the exonic enhancers are found to be co-occurring with multiple exonic silencers and vice versa, which demonstrates a complicated relationship between tissue-specific exonic enhancers and silencers.

Computation and application of tissue-specific gene set weights.

PubMed

Frost, H Robert

2018-04-06

Gene set testing, or pathway analysis, has become a critical tool for the analysis of highdimensional genomic data. Although the function and activity of many genes and higher-level processes is tissue-specific, gene set testing is typically performed in a tissue agnostic fashion, which impacts statistical power and the interpretation and replication of results. To address this challenge, we have developed a bioinformatics approach to compute tissuespecific weights for individual gene sets using information on tissue-specific gene activity from the Human Protein Atlas (HPA). We used this approach to create a public repository of tissue-specific gene set weights for 37 different human tissue types from the HPA and all collections in the Molecular Signatures Database (MSigDB). To demonstrate the validity and utility of these weights, we explored three different applications: the functional characterization of human tissues, multi-tissue analysis for systemic diseases and tissue-specific gene set testing. All data used in the reported analyses is publicly available. An R implementation of the method and tissue-specific weights for MSigDB gene set collections can be downloaded at http://www.dartmouth.edu/∼hrfrost/TissueSpecificGeneSets. rob.frost@dartmouth.edu.

HLA-G peptide preferences change in transformed cells: impact on the binding motif.

PubMed

Celik, Alexander A; Simper, Gwendolin S; Hiemisch, Wiebke; Blasczyk, Rainer; Bade-Döding, Christina

2018-03-30

HLA-G is known for its strictly restricted tissue distribution. HLA-G expression could be detected in immune privileged organs and many tumor entities such as leukemia, multiple myeloma, and non-Hodgkin and Hodgkin's lymphoma. This functional variability from mediation of immune tolerance to facilitation of tumor immune evasion strategies might translate to a differential NK cell inhibition between immune-privileged organs and tumor cells. The biophysical invariability of the HLA-G heavy chain and its contrary diversity in immunity implicates a strong influence of the bound peptides on the pHLA-G structure. The aim was to determine if HLA-G displays a tissue-specific peptide repertoire. Therefore, using soluble sHLA-G technology, we analyzed the K562 and HDLM-2 peptide repertoires. Although both cell lines possess a comparable proteome and recruit HLA-G-restricted peptides through the same peptide-loading pathway, the peptide features appear to be cell specific. HDLM-2 derived HLA-G peptides are anchored by an Arg at p1 and K562-derived peptides are anchored by a Lys. At p2, no anchor motif could be determined while peptides were anchored at pΩ with a Leu and showed an auxiliary anchor motif Pro at p3. To appreciate if the peptide anchor alterations are due to a cell-specific differential peptidome, we performed analysis of peptide availability within the different cell types. Yet, the comparison of the cell-specific proteome and HLA-G-restricted ligandome clearly demonstrates a tissue-specific peptide selection by HLA-G molecules. This exclusive and unexpected observation suggests an exquisite immune function of HLA-G.

Establishment of a tissue-specific RNAi system in C. elegans.

PubMed

Qadota, Hiroshi; Inoue, Makiko; Hikita, Takao; Köppen, Mathias; Hardin, Jeffrey D; Amano, Mutsuki; Moerman, Donald G; Kaibuchi, Kozo

2007-10-01

In C. elegans, mosaic analysis is a powerful genetic tool for determining in which tissue or specific cells a gene of interest is required. For traditional mosaic analysis, a loss-of-function mutant and a genomic fragment that can rescue the mutant phenotype are required. Here we establish an easy and rapid mosaic system using RNAi (RNA mediated interference), using a rde-1 mutant that is resistant to RNAi. Tissue-specific expression of the wild type rde-1 cDNA in rde-1 mutants limits RNAi sensitivity to a specific tissue. We established hypodermal-and muscle-specific RNAi systems by expressing rde-1 cDNA under the control of the lin-26 and hlh-1 promoters, respectively. We confirmed tissue-specific RNAi using two assays: (1) tissue-specific knockdown of GFP expression, and (2) phenocopy of mutations in essential genes that were previously known to function in a tissue-specific manner. We also applied this system to an essential gene, ajm-1, expressed in hypodermis and gut, and show that lethality in ajm-1 mutants is due to loss of expression in hypodermal cells. Although we demonstrate tissue-specific RNAi in hypodermis and muscle, this method could be easily applied to other tissues.

Establishment of a tissue-specific RNAi system in C. elegans

PubMed Central

Qadota, Hiroshi; Inoue, Makiko; Hikita, Takao; Köppen, Mathias; Hardin, Jeffrey D.; Amano, Mutsuki; Moerman, Donald G.; Kaibuchi, Kozo

2011-01-01

In C. elegans, mosaic analysis is a powerful genetic tool for determining in which tissue or specific cells a gene of interest is required. For traditional mosaic analysis, a loss-of-function mutant and a genomic fragment that can rescue the mutant phenotype are required. Here we establish an easy and rapid mosaic system using RNAi (RNA mediated interference), using a rde-1 mutant that is resistant to RNAi. Tissue-specific expression of the wild type rde-1 cDNA in rde-1 mutants limits RNAi sensitivity to a specific tissue. We established hypodermal- and muscle-specific RNAi systems by expressing rde-1 cDNA under the control of the lin-26 and hlh-1 promoters, respectively. We confirmed tissue-specific RNAi using two assays: (1) tissue-specific knockdown of GFP expression, and (2) phenocopy of mutations in essential genes that were previously known to function in a tissue-specific manner. We also applied this system to an essential gene, ajm-1, expressed in hypodermis and gut, and show that lethality in ajm-1 mutants is due to loss of expression in hypodermal cells. Although we demonstrate tissue-specific RNAi in hypodermis and muscle, this method could be easily applied to other tissues. PMID:17681718

Purification and biochemical characterization of a novel ecto-apyrase, MP67, from Mimosa pudica.

PubMed

Okuhata, Riku; Takishima, Takeshi; Nishimura, Naoaki; Ueda, Shogo; Tsuchiya, Takahide; Kanzawa, Nobuyuki

2011-09-01

We have previously reported the presence of an apyrase in Mimosa pudica. However, only limited information is available for this enzyme. Thus, in this study, the apyrase was purified to homogeneity. The purified enzyme had a molecular mass of around 67 kD and was able to hydrolyze both nucleotide triphosphate and nucleotide diphosphate as substrates. The ratio of ATP to ADP hydrolysis velocity of the purified protein was 0.01 in the presence of calcium ion, showing extremely high substrate specificity toward ADP. Thus, we designated this novel apyrase as MP67. A cDNA clone of MP67 was obtained using primers designed from the amino acid sequence of trypsin-digested fragments of the protein. In addition, rapid amplification of cDNA ends-polymerase chain reaction was performed to clone a conventional apyrase (MpAPY2). Comparison of the deduced amino acid sequences showed that MP67 is similar to ecto-apyrases; however, it was distinct from conventional apyrase based on phylogenetic classification. MP67 and MpAPY2 were expressed in Escherichia coli, and the recombinant proteins were purified. The recombinant MP67 showed high substrate specificity toward ADP rather than ATP. A polyclonal antibody raised against the recombinant MP67 was used to examine the tissue distribution and localization of native MP67 in the plant. The results showed that MP67 was ubiquitously distributed in various tissues, most abundantly in leaves, and was localized to plasma membranes. Thus, MP67 is a novel ecto-apyrase with extremely high substrate specificity for ADP.

Purification and Biochemical Characterization of a Novel Ecto-Apyrase, MP67, from Mimosa pudica1[C][W][OA

PubMed Central

Okuhata, Riku; Takishima, Takeshi; Nishimura, Naoaki; Ueda, Shogo; Tsuchiya, Takahide; Kanzawa, Nobuyuki

2011-01-01

We have previously reported the presence of an apyrase in Mimosa pudica. However, only limited information is available for this enzyme. Thus, in this study, the apyrase was purified to homogeneity. The purified enzyme had a molecular mass of around 67 kD and was able to hydrolyze both nucleotide triphosphate and nucleotide diphosphate as substrates. The ratio of ATP to ADP hydrolysis velocity of the purified protein was 0.01 in the presence of calcium ion, showing extremely high substrate specificity toward ADP. Thus, we designated this novel apyrase as MP67. A cDNA clone of MP67 was obtained using primers designed from the amino acid sequence of trypsin-digested fragments of the protein. In addition, rapid amplification of cDNA ends-polymerase chain reaction was performed to clone a conventional apyrase (MpAPY2). Comparison of the deduced amino acid sequences showed that MP67 is similar to ecto-apyrases; however, it was distinct from conventional apyrase based on phylogenetic classification. MP67 and MpAPY2 were expressed in Escherichia coli, and the recombinant proteins were purified. The recombinant MP67 showed high substrate specificity toward ADP rather than ATP. A polyclonal antibody raised against the recombinant MP67 was used to examine the tissue distribution and localization of native MP67 in the plant. The results showed that MP67 was ubiquitously distributed in various tissues, most abundantly in leaves, and was localized to plasma membranes. Thus, MP67 is a novel ecto-apyrase with extremely high substrate specificity for ADP. PMID:21788364

Noninvasive Imaging of PSMA in prostate tumors with (89)Zr-Labeled huJ591 engineered antibody fragments: the faster alternatives.

PubMed

Viola-Villegas, Nerissa Therese; Sevak, Kuntal K; Carlin, Sean D; Doran, Michael G; Evans, Henry W; Bartlett, Derek W; Wu, Anna M; Lewis, Jason S

2014-11-03

Engineered antibody fragments offer faster delivery with retained tumor specificity and rapid clearance from nontumor tissues. Here, we demonstrate that positron emission tomography (PET) based detection of prostate specific membrane antigen (PSMA) in prostatic tumor models using engineered bivalent antibodies built on single chain fragments (scFv) derived from the intact antibody, huJ591, offers similar tumor delineating properties but with the advantage of rapid targeting and imaging. (89)Zr-radiolabeled huJ591 scFv (dimeric scFv-CH3; (89)Zr-Mb) and cysteine diabodies (dimeric scFv; (89)Zr-Cys-Db) demonstrated internalization and similar Kds (∼2 nM) compared to (89)Zr-huJ591 in PSMA(+) cells. Tissue distribution assays established the specificities of both (89)Zr-Mb and (89)Zr-Cys-Db for PSMA(+) xenografts (6.2 ± 2.5% ID/g and 10.2 ± 3.4% ID/g at 12 h p.i. respectively), while minimal accumulation in PSMA(-) tumors was observed. From the PET images, (89)Zr-Mb and (89)Zr-Cys-Db exhibited faster blood clearance than the parent huJ591 while tumor-to-muscle ratios for all probes show comparable values across all time points. Ex vivo autoradiography and histology assessed the distribution of the probes within the tumor. Imaging PSMA-expressing prostate tumors with smaller antibody fragments offers rapid tumor accumulation and accelerated clearance; hence, shortened wait periods between tracer administration and high-contrast tumor imaging and lower dose-related toxicity are potentially realized.

Quantitative prediction of radio frequency induced local heating derived from measured magnetic field maps in magnetic resonance imaging: A phantom validation at 7 T

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

Zhang, Xiaotong; Liu, Jiaen; Van de Moortele, Pierre-Francois

2014-12-15

Electrical Properties Tomography (EPT) technique utilizes measurable radio frequency (RF) coil induced magnetic fields (B1 fields) in a Magnetic Resonance Imaging (MRI) system to quantitatively reconstruct the local electrical properties (EP) of biological tissues. Information derived from the same data set, e.g., complex numbers of B1 distribution towards electric field calculation, can be used to estimate, on a subject-specific basis, local Specific Absorption Rate (SAR). SAR plays a significant role in RF pulse design for high-field MRI applications, where maximum local tissue heating remains one of the most constraining limits. The purpose of the present work is to investigate themore » feasibility of such B1-based local SAR estimation, expanding on previously proposed EPT approaches. To this end, B1 calibration was obtained in a gelatin phantom at 7 T with a multi-channel transmit coil, under a particular multi-channel B1-shim setting (B1-shim I). Using this unique set of B1 calibration, local SAR distribution was subsequently predicted for B1-shim I, as well as for another B1-shim setting (B1-shim II), considering a specific set of parameter for a heating MRI protocol consisting of RF pulses plaid at 1% duty cycle. Local SAR results, which could not be directly measured with MRI, were subsequently converted into temperature change which in turn were validated against temperature changes measured by MRI Thermometry based on the proton chemical shift.« less

Regulative feedback in pattern formation: towards a general relativistic theory of positional information.

PubMed

Jaeger, Johannes; Irons, David; Monk, Nick

2008-10-01

Positional specification by morphogen gradients is traditionally viewed as a two-step process. A gradient is formed and then interpreted, providing a spatial metric independent of the target tissue, similar to the concept of space in classical mechanics. However, the formation and interpretation of gradients are coupled, dynamic processes. We introduce a conceptual framework for positional specification in which cellular activity feeds back on positional information encoded by gradients, analogous to the feedback between mass-energy distribution and the geometry of space-time in Einstein's general theory of relativity. We discuss how such general relativistic positional information (GRPI) can guide systems-level approaches to pattern formation.

A specific colorimetric assay for measuring transglutaminase 1 and factor XIII activities.

PubMed

Hitomi, Kiyotaka; Kitamura, Miyako; Alea, Mileidys Perez; Ceylan, Ismail; Thomas, Vincent; El Alaoui, Saïd

2009-11-15

Transglutaminase (TGase) is an enzyme that catalyzes both isopeptide cross-linking and incorporation of primary amines into proteins. Eight TGases have been identified in humans, and each of these TGases has a unique tissue distribution and physiological significance. Although several assays for TGase enzymatic activity have been reported, it has been difficult to establish an assay for discriminating each of these different TGase activities. Using a random peptide library, we recently identified the preferred substrate sequences for three major TGases: TGase 1, TGase 2, and factor XIII. In this study, we use these substrates in specific tests for measuring the activities of TGase 1 and factor XIII.

A hybrid approach to advancing quantitative prediction of tissue distribution of basic drugs in human

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

Poulin, Patrick, E-mail: patrick-poulin@videotron.ca; Ekins, Sean; Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, 20 Penn Street, Baltimore, MD 21201

A general toxicity of basic drugs is related to phospholipidosis in tissues. Therefore, it is essential to predict the tissue distribution of basic drugs to facilitate an initial estimate of that toxicity. The objective of the present study was to further assess the original prediction method that consisted of using the binding to red blood cells measured in vitro for the unbound drug (RBCu) as a surrogate for tissue distribution, by correlating it to unbound tissue:plasma partition coefficients (Kpu) of several tissues, and finally to predict volume of distribution at steady-state (V{sub ss}) in humans under in vivo conditions. Thismore » correlation method demonstrated inaccurate predictions of V{sub ss} for particular basic drugs that did not follow the original correlation principle. Therefore, the novelty of this study is to provide clarity on the actual hypotheses to identify i) the impact of pharmacological mode of action on the generic correlation of RBCu-Kpu, ii) additional mechanisms of tissue distribution for the outlier drugs, iii) molecular features and properties that differentiate compounds as outliers in the original correlation analysis in order to facilitate its applicability domain alongside the properties already used so far, and finally iv) to present a novel and refined correlation method that is superior to what has been previously published for the prediction of human V{sub ss} of basic drugs. Applying a refined correlation method after identifying outliers would facilitate the prediction of more accurate distribution parameters as key inputs used in physiologically based pharmacokinetic (PBPK) and phospholipidosis models.« less

An electromechanical based deformable model for soft tissue simulation.

PubMed

Zhong, Yongmin; Shirinzadeh, Bijan; Smith, Julian; Gu, Chengfan

2009-11-01

Soft tissue deformation is of great importance to surgery simulation. Although a significant amount of research efforts have been dedicated to simulating the behaviours of soft tissues, modelling of soft tissue deformation is still a challenging problem. This paper presents a new deformable model for simulation of soft tissue deformation from the electromechanical viewpoint of soft tissues. Soft tissue deformation is formulated as a reaction-diffusion process coupled with a mechanical load. The mechanical load applied to a soft tissue to cause a deformation is incorporated into the reaction-diffusion system, and consequently distributed among mass points of the soft tissue. Reaction-diffusion of mechanical load and non-rigid mechanics of motion are combined to govern the simulation dynamics of soft tissue deformation. An improved reaction-diffusion model is developed to describe the distribution of the mechanical load in soft tissues. A three-layer artificial cellular neural network is constructed to solve the reaction-diffusion model for real-time simulation of soft tissue deformation. A gradient based method is established to derive internal forces from the distribution of the mechanical load. Integration with a haptic device has also been achieved to simulate soft tissue deformation with haptic feedback. The proposed methodology does not only predict the typical behaviours of living tissues, but it also accepts both local and large-range deformations. It also accommodates isotropic, anisotropic and inhomogeneous deformations by simple modification of diffusion coefficients.

P/CAF Function in Transcriptional Activation by Steroid Hormone Receptors and Mammary Cell Proliferation

DTIC Science & Technology

1999-07-01

author(s) and should not be construed as an official Department of the Army position, policy or decision unless so designated by other documentation...material. Where material from documents designated for limited distribution is quoted, permission has been obtained to use the material. Citations of...mammary tissue in the PCAF knock out mice, was actually completed last year. We are beginning the design and cloning of the breast-specific knock out

Task Dependence, Tissue Specificity, and Spatial Distribution of Widespread Activations in Large Single-Subject Functional MRI Datasets at 7T

PubMed Central

Gonzalez-Castillo, Javier; Hoy, Colin W.; Handwerker, Daniel A.; Roopchansingh, Vinai; Inati, Souheil J.; Saad, Ziad S.; Cox, Robert W.; Bandettini, Peter A.

2015-01-01

It was recently shown that when large amounts of task-based blood oxygen level–dependent (BOLD) data are combined to increase contrast- and temporal signal-to-noise ratios, the majority of the brain shows significant hemodynamic responses time-locked with the experimental paradigm. Here, we investigate the biological significance of such widespread activations. First, the relationship between activation extent and task demands was investigated by varying cognitive load across participants. Second, the tissue specificity of responses was probed using the better BOLD signal localization capabilities of a 7T scanner. Finally, the spatial distribution of 3 primary response types—namely positively sustained (pSUS), negatively sustained (nSUS), and transient—was evaluated using a newly defined voxel-wise waveshape index that permits separation of responses based on their temporal signature. About 86% of gray matter (GM) became significantly active when all data entered the analysis for the most complex task. Activation extent scaled with task load and largely followed the GM contour. The most common response type was nSUS BOLD, irrespective of the task. Our results suggest that widespread activations associated with extremely large single-subject functional magnetic resonance imaging datasets can provide valuable information about the functional organization of the brain that goes undetected in smaller sample sizes. PMID:25405938

Distinct structure and activity of monoamine oxidase in the brain of zebrafish (Danio rerio).

PubMed

Anichtchik, Oleg; Sallinen, Ville; Peitsaro, Nina; Panula, Pertti

2006-10-10

Monoamine oxidase (MAO) is a mitochondrial flavoprotein involved in the metabolism of, e.g., aminergic neurotransmitters and the parkinsonism-inducing neurotoxin 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine (MPTP). We have reported earlier MPTP-related alterations of brain catecholaminergic system in zebrafish (Danio rerio) brain. Here we describe the structural and functional properties of zebrafish MAO and the distribution of MAO mRNA and activity in zebrafish brain. The gene is located in chromosome 9 and consists of 15 exons. The amino acid composition of the active center resembles both human MAO-A and MAO-B. The enzyme displayed the highest substrate specificity for tyramine, followed by serotonin, phenylethylamine, MPTP, and dopamine; isoform-specific antagonists blocked the activity of the enzyme with equal potency. Zebrafish MAO mRNA, which was present in several tissues, and enzyme displayed differential distribution in the brain; dopaminergic cell clusters had low to moderate levels of MAO activity, whereas the highest levels of MAO activity were detected in noradrenergic and serotonergic cell groups and the habenulointerpeduncular pathway, including its caudal projection to the medial ventral rhombencephalon. The results of this study confirm the presence of functionally active MAO in zebrafish brain and other tissues and characterize the neural systems that express MAO and areas of intense activity in the brain. They also suggest that MPTP toxicity not related to MAO may affect the zebrafish brain.

Spleen-specific suppression of TNF-alpha by cationic hydrogel-delivered antisense nucleotides for the prevention of arthritis in animal models.

PubMed

Dong, Lei; Xia, Suhua; Chen, Huan; Chen, Jiangning; Zhang, Junfeng

2009-09-01

This study developed a transplantable platform based on cationic hydrogels to deliver antisense oligodeoxynucleotides (ASOs) targeting the mRNA of TNF-alpha. Cationic agarose (c-agarose) was obtained by conjugating ethylenediamine to agarose via an N,N'-carbonyldiimidazole (CDI)-activation method. ASO-c-agarose system was constructed by mixing ASO in cationic agarose gel of proper concentration and gelation temperature. In vivo assessment of ASO distribution suggested that the system specifically target to spleen, wherein the c-agarose-delivered ASO had a concentration remarkably 50-fold higher than that of the naked ASO. The distribution of c-agarose-delivered ASO was scarcely detectable in liver and kidney. Next, three types of animal models were setup to evaluate the therapeutic efficacies of ASO-Gel, including the adjuvant-induced arthritis (AA), carrageen/lipopolysaccharide (LPS)-induced arthritis (CLA) and collagen-induced arthritis (CIA) models. The effects of ASO-c-agarose in alleviating inflammation and tissue destruction were evidenced in more than 90% of the testing animals, with decrease of main inflammatory cytokines, lightening of joint swelling and tissue damage, as well as increase in their body weights. All these findings suggest that this highly operable devise for the conveyance of antisense nucleotides together with its spleen-targeting property, could become a useful means of antisense-based therapeutics against rheumatoid arthritis and other diseases.

Genome-wide analysis of basic/helix-loop-helix gene family in peanut and assessment of its roles in pod development.

PubMed

Gao, Chao; Sun, Jianlei; Wang, Chongqi; Dong, Yumei; Xiao, Shouhua; Wang, Xingjun; Jiao, Zigao

2017-01-01

The basic/helix-loop-helix (bHLH) proteins constitute a superfamily of transcription factors that are known to play a range of regulatory roles in eukaryotes. Over the past few decades, many bHLH family genes have been well-characterized in model plants, such as Arabidopsis, rice and tomato. However, the bHLH protein family in peanuts has not yet been systematically identified and characterized. Here, 132 and 129 bHLH proteins were identified from two wild ancestral diploid subgenomes of cultivated tetraploid peanuts, Arachis duranensis (AA) and Arachis ipaensis (BB), respectively. Phylogenetic analysis indicated that these bHLHs could be classified into 19 subfamilies. Distribution mapping results showed that peanut bHLH genes were randomly and unevenly distributed within the 10 AA chromosomes and 10 BB chromosomes. In addition, 120 bHLH gene pairs between the AA-subgenome and BB-subgenome were found to be orthologous and 101 of these pairs were highly syntenic in AA and BB chromosomes. Furthermore, we confirmed that 184 bHLH genes expressed in different tissues, 22 of which exhibited tissue-specific expression. Meanwhile, we identified 61 bHLH genes that may be potentially involved in peanut-specific subterranean. Our comprehensive genomic analysis provides a foundation for future functional dissection and understanding of the regulatory mechanisms of bHLH transcription factors in peanuts.

Zebrafish Oatp-mediated transport of microcystin congeners.

PubMed

Steiner, Konstanze; Zimmermann, Lisa; Hagenbuch, Bruno; Dietrich, Daniel

2016-05-01

Microcystins (MC), representing >100 congeners being produced by cyanobacteria, are a hazard for aquatic species. As MC congeners vary in their toxicity, the congener composition of a bloom primarily dictates the severity of adverse effects and appears primarily to be governed by toxicokinetics, i.e., whether transport of MCs occurs via organic anion-transporting polypeptides (Oatps). Differences in observed MC toxicity in various fish species suggest differential expression of Oatp subtypes leading to varying tissue distribution of the very same MC congener within different species. The objectives of this study were the functional characterization and analysis of the tissue distribution of Oatp subtypes in zebrafish (Danio rerio) as a surrogate model for cyprinid fish. Zebrafish Oatps (zfOatps) were cloned, and the organ distribution was determined at the mRNA level. zfOatps were transiently expressed in HEK293 cells for functional characterization using the Oatp substrates estrone-3-sulfate, taurocholate and methotrexate and specific MC congeners (MC-LR, MC-RR, MC-LF and MC-LW). Novel zfOatp isoforms were isolated. Among these isoforms, the organ-specific expression of zfOatp1d1 and of members of the zfOatp1f subfamily was identified. At the functional level, zfOatp1d1, zfOatp1f2, zfOatp1f3 and zfOatp1f4 transported at least one of the Oatp substrates, and zfOatp1d1, zfOatp1f2 and zfOatp1f4 were shown to transport MC congeners. MC-LF and MC-LW were generally transported faster than MC-LR and MC-RR. The subtype-specific expression of zfOatp1d1 and of members of the zfOatp1f subfamily as well as differences in the transport of MC congeners could explain the MC congener-dependent differences in toxicity in cyprinids.

Preparation and characterization of a novel Al(18)F-NOTA-BZA conjugate for melanin-targeted imaging of malignant melanoma.

PubMed

Chang, Chih-Chao; Chang, Chih-Hsien; Lo, Yi-Hsuan; Lin, Ming-Hsien; Shen, Chih-Chieh; Liu, Ren-Shyan; Wang, Hsin-Ell; Chen, Chuan-Lin

2016-08-15

Melanin is an attractive target for the diagnosis and treatment of malignant melanoma. Previous studies have demonstrated the specific binding ability of benzamide moiety to melanin. In this study, we developed a novel (18)F-labeled NOTA-benzamide conjugate, Al(18)F-NOTA-BZA, which can be synthesized in 30min with a radiochemical yield of 20-35% and a radiochemical purity of >95%. Al(18)F-NOTA-BZA is highly hydrophilic (logP=-1.96) and shows good in vitro stability. Intravenous administration of Al(18)F-NOTA-BZA in two melanoma-bearing mouse models revealed highly specific uptake in B16F0 melanotic melanoma (6.67±0.91 and 1.50±0.26%ID/g at 15 and 120min p.i., respectively), but not in A375 amelanotic melanoma (0.87±0.21 and 0.24±0.09%ID/g at 15 and 120min p.i., respectively). The clearance from most normal tissues was fast. A microPET scan of Al(18)F-NOTA-BZA-injected mice also displayed high-contrast tumor images as compared with normal organs. Owing to the favorable in vivo distribution of Al(18)F-NOTA-BZA after intravenous administration, the estimated absorption dose was low in all normal organs and tissues. The melanin-specific binding ability, sustained tumor retention, fast normal tissues clearance and thelow projected human dosimetry supported that Al(18)F-NOTA-BZA is a very promising melanin-specific PET probe for melanin-positive melanoma. Copyright © 2016 Elsevier Ltd. All rights reserved.

A clinically applicable non-invasive method to quantitatively assess the visco-hyperelastic properties of human heel pad, implications for assessing the risk of mechanical trauma.

PubMed

Behforootan, Sara; Chatzistergos, Panagiotis E; Chockalingam, Nachiappan; Naemi, Roozbeh

2017-04-01

Pathological conditions such as diabetic foot and plantar heel pain are associated with changes in the mechanical properties of plantar soft tissue. However, the causes and implications of these changes are not yet fully understood. This is mainly because accurate assessment of the mechanical properties of plantar soft tissue in the clinic remains extremely challenging. To develop a clinically viable non-invasive method of assessing the mechanical properties of the heel pad. Furthermore the effect of non-linear mechanical behaviour of the heel pad on its ability to uniformly distribute foot-ground contact loads in light of the effect of overloading is also investigated. An automated custom device for ultrasound indentation was developed along with custom algorithms for the automated subject-specific modeling of heel pad. Non-time-dependent and time-dependent material properties were inverse engineered from results from quasi-static indentation and stress relaxation test respectively. The validity of the calculated coefficients was assessed for five healthy participants. The implications of altered mechanical properties on the heel pad's ability to uniformly distribute plantar loading were also investigated in a parametric analysis. The subject-specific heel pad models with coefficients calculated based on quasi-static indentation and stress relaxation were able to accurately simulate dynamic indentation. Average error in the predicted forces for maximum deformation was only 6.6±4.0%. When the inverse engineered coefficients were used to simulate the first instance of heel strike the error in terms of peak plantar pressure was 27%. The parametric analysis indicated that the heel pad's ability to uniformly distribute plantar loads is influenced both by its overall deformability and by its stress-strain behaviour. When overall deformability stays constant, changes in stress/strain behaviour leading to a more "linear" mechanical behaviour appear to improve the heel pad's ability to uniformly distribute plantar loading. The developed technique can accurately assess the visco-hyperelastic behaviour of heel pad. It was observed that specific change in stress-strain behaviour can enhance/weaken the heel pad's ability to uniformly distribute plantar loading that will increase/decrease the risk for overloading and trauma. Copyright © 2017 Elsevier Ltd. All rights reserved.

Patient-specific dosimetry based on quantitative SPECT imaging and 3D-DFT convolution

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

Akabani, G.; Hawkins, W.G.; Eckblade, M.B.

1999-01-01

The objective of this study was to validate the use of a 3-D discrete Fourier Transform (3D-DFT) convolution method to carry out the dosimetry for I-131 for soft tissues in radioimmunotherapy procedures. To validate this convolution method, mathematical and physical phantoms were used as a basis of comparison with Monte Carlo transport (MCT) calculations which were carried out using the EGS4 system code. The mathematical phantom consisted of a sphere containing uniform and nonuniform activity distributions. The physical phantom consisted of a cylinder containing uniform and nonuniform activity distributions. Quantitative SPECT reconstruction was carried out using the Circular Harmonic Transformmore » (CHT) algorithm.« less

Organ and Tissue-Specific Localisation of Selected Cell Wall Epitopes in the Zygotic Embryo of Brachypodium distachyon.

PubMed

Betekhtin, Alexander; Milewska-Hendel, Anna; Lusinska, Joanna; Chajec, Lukasz; Kurczynska, Ewa; Hasterok, Robert

2018-03-03

The plant cell wall shows a great diversity regarding its chemical composition, which may vary significantly even during different developmental stages. In this study, we analysed the distribution of several cell wall epitopes in embryos of Brachypodium distachyon (Brachypodium). We also described the variations in the nucleus shape and the number of nucleoli that occurred in some embryo cells. The use of transmission electron microscopy, and histological and immunolocalisation techniques permitted the distribution of selected arabinogalactan proteins, extensins, pectins, and hemicelluloses on the embryo surface, internal cell compartments, and in the context of the cell wall ultrastructure to be demonstrated. We revealed that the majority of arabinogalactan proteins and extensins were distributed on the cell surface and that pectins were the main component of the seed coat and other parts, such as the mesocotyl cell walls and the radicula. Hemicelluloses were localised in the cell wall and outside of the radicula protodermis, respectively. The specific arrangement of those components may indicate their significance during embryo development and seed germination, thus suggesting the importance of their protective functions. Despite the differences in the cell wall composition, we found that some of the antibodies can be used as markers to identify specific cells and the parts of the developing Brachypodium embryo.

Does bariatric surgery improve adipose tissue function?

PubMed Central

Frikke-Schmidt, H.; O’Rourke, R. W.; Lumeng, C. N.; Sandoval, D. A.; Seeley, R. J.

2017-01-01

Summary Bariatric surgery is currently the most effective treatment for obesity. Not only do these types of surgeries produce significant weight loss but also they improve insulin sensitivity and whole body metabolic function. The aim of this review is to explore how altered physiology of adipose tissue may contribute to the potent metabolic effects of some of these procedures. This includes specific effects on various fat depots, the function of individual adipocytes and the interaction between adipose tissue and other key metabolic tissues. Besides a dramatic loss of fat mass, bariatric surgery shifts the distribution of fat from visceral to the subcutaneous compartment favoring metabolic improvement. The sensitivity towards lipolysis controlled by insulin and catecholamines is improved, adipokine secretion is altered and local adipose inflammation as well as systemic inflammatory markers decreases. Some of these changes have been shown to be weight loss independent, and novel hypothesis for these effects includes include changes in bile acid metabolism, gut microbiota and central regulation of metabolism. In conclusion bariatric surgery is capable of improving aspects of adipose tissue function and do so in some cases in ways that are not entirely explained by the potent effect of surgery. PMID:27272117

The expression of embryonic primary mesenchyme genes of the sea urchin, Strongylocentrotus purpuratus, in the adult skeletogenic tissues of this and other species of echinoderms.

PubMed

Drager, B J; Harkey, M A; Iwata, M; Whiteley, A H

1989-05-01

Adult tissues of the sea urchin, Strongylocentrotus purpuratus, were analyzed for the products of a set of genes whose expression, in the embryo, is restricted to the skeletogenic primary mesenchyme (PM). Three embryonic PM-specific mRNAs were found to be abundant in adult skeletal tissues (test and lantern), but not in a variety of soft tissues. Homologous mRNAs were also found in skeletal tissues of the congeneric sea urchin, S. droebachiensis, as well as a more distantly related echinoid, Dendraster excentricus, and an asteroid, Evasterias troschellii. The distributions of two of these RNAs were analyzed in regenerating spines of adult S. purpuratus using in situ hybridization. These gene products were localized primarily in the calcoblasts that accumulated at the regeneration site. In nonregenerating spines SpLM 18 RNAs, the most abundant of these gene products, were localized in a small population of noncalcoblast cells scattered through the spine shaft, and were absent from calcoblasts. These observations suggest that a program of gene expression associated with the process of calcification is conserved both developmentally through the period of metamorphosis and evolutionarily among the echinoderms.

Bullet Retarding Forces in Ballistic Gelatin by Analysis of High Speed Video

DTIC Science & Technology

2012-12-28

tends to be close to the projectile path through tissue. The permanent cavity may be enlarged if the tissue is stretched beyond the elastic limit...inertia, weight, and elasticity causes it to spring back into place. Inelastic tissues such as liver, spleen, and brain stretch much less than... elastic tissues such as 1 Distribution A. Approved for public release. Distribution unlimited. The views expressed in this paper are those of the

A Reconstruction Algorithm of Magnetoacoustic Tomography with Magnetic Induction for Acoustically Inhomogeneous Tissue

PubMed Central

Zhou, Lian; Zhu, Shanan

2014-01-01

Magnetoacoustic tomography with Magnetic Induction (MAT-MI) is a noninvasive electrical conductivity imaging approach that measures ultrasound wave induced by magnetic stimulation, for reconstructing the distribution of electrical impedance in biological tissue. Existing reconstruction algorithms for MAT-MI are based on the assumption that the acoustic properties in the tissue are homogeneous. However, the tissue in most parts of human body, has heterogeneous acoustic properties, which leads to potential distortion and blurring of small buried objects in the impedance images. In the present study, we proposed a new algorithm for MAT-MI to image the impedance distribution in tissues with inhomogeneous acoustic speed distributions. With a computer head model constructed from MR images of a human subject, a series of numerical simulation experiments were conducted. The present results indicate that the inhomogeneous acoustic properties of tissues in terms of speed variation can be incorporated in MAT-MI imaging. PMID:24845284

Bioimaging of metallothioneins in ocular tissue sections by laser ablation-ICP-MS using bioconjugated gold nanoclusters as specific tags.

PubMed

Cruz-Alonso, María; Fernandez, Beatriz; Álvarez, Lydia; González-Iglesias, Héctor; Traub, Heike; Jakubowski, Norbert; Pereiro, Rosario

2017-12-18

An immunohistochemical method is described to visualize the distribution of metallothioneins 1/2 (MT 1/2) and metallothionein 3 (MT 3) in human ocular tissue. It is making use of (a) antibodies conjugated to gold nanoclusters (AuNCs) acting as labels, and (b) laser ablation (LA) coupled to inductively coupled plasma - mass spectrometry (ICP-MS). Water-soluble fluorescent AuNCs (with an average size of 2.7 nm) were synthesized and then conjugated to antibody by carbodiimide coupling. The surface of the modified AuNCs was then blocked with hydroxylamine to avoid nonspecific interactions with biological tissue. Immunoassays for MT 1/2 and MT 3 in ocular tissue sections (5 μm thick) from two post mortem human donors were performed. Imaging studies were then performed by fluorescence using confocal microscopy, and LA-ICP-MS was performed in the retina to measure the signal for gold. Signal amplification by the >500 gold atoms in each nanocluster allowed the antigens (MT 1/2 and MT 3) to be imaged by LA-ICP-MS using a laser spot size as small as 4 μm. The image patterns found in retina are in good agreement with those obtained by conventional fluorescence immunohistochemistry which was used as an established reference method. Graphical abstract Gold nanoclusters (AuNCs) conjugated to a primary specific antibody serve as a label for amplified bioimaging of metallothioneins (MTs) by laser ablation coupled to inductively coupled plasma - mass spectrometry (ICP-MS) in human ocular tissue sections.

The accumulation and localization of chalcone synthase in grapevine (Vitis vinifera L.).

PubMed

Wang, Huiling; Wang, Wei; Zhan, JiCheng; Yan, Ailing; Sun, Lei; Zhang, Guojun; Wang, Xiaoyue; Ren, Jiancheng; Huang, Weidong; Xu, Haiying

2016-09-01

Chalcone synthase (CHS, E.C.2.3.1.74) is the first committed enzyme in the flavonoid pathway. Previous studies have primarily focused on the cloning, expression and regulation of the gene at the transcriptional level. Little is yet known about the enzyme accumulation, regulation at protein level, as well as its localization in grapevine. In present study, the accumulation, tissue and subcellular localization of CHS in different grapevine tissues (Vitis vinifera L. Cabernet Sauvignon) were investigated via the techniques of Western blotting, immunohistochemical localization, immunoelectron microscopy and confocal microscopy. The results showed that CHS were mainly accumulated in the grape berry skin, leaves, stem tips and stem phloem, correlated with flavonoids accumulation. The accumulation of CHS is developmental dependent in grape berry skin and flesh. Immunohistochemical analysis revealed that CHS were primarily localized in the exocarp and vascular bundles of the fruits during berry development; in palisade, spongy tissues and vascular bundles of the leaves; in the primary phloem and pith ray in the stems; in the growth point, leaf primordium, and young leaves of leaf buds; and in the endoderm and primary phloem of grapevine roots. Furthermore, at the subcellular level, the cell wall, cytoplasm and nucleus localized patterns of CHS were observed in the grapevine vegetative tissue cells. Results above indicated that distribution of CHS in grapevine was organ-specific and tissue-specific. This work will provide new insight for the biosynthesis and regulation of diverse flavonoid compounds in grapevine. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Visualization and Semiquantitative Study of the Distribution of Major Components in Wheat Straw in Mesoscopic Scale using Fourier Transform Infrared Microspectroscopic Imaging.

PubMed

Yang, Zengling; Mei, Jiaqi; Liu, Zhiqiang; Huang, Guangqun; Huang, Guan; Han, Lujia

2018-06-19

Understanding the biochemical heterogeneity of plant tissue linked to crop straw anatomy is attractive to plant researchers and researchers in the field of biomass refinery. This study provides an in situ analysis and semiquantitative visualization of major components distribution in internodal transverse sections of wheat straw based on Fourier transform infrared (FTIR) microspectroscopic imaging, with a fast non-negativity-constrained least squares (fast NNLS) fitting. This paper investigates changes in biochemical components of tissue during stages of elongation, booting, heading, flowering, grain-filling, milk-ripening, dough, and full-ripening. Visualization analysis was carried out with reference spectra for five components (microcrystalline cellulose, xylan, lignin, pectin, and starch) of wheat straw. Our result showed that (a) the cellulose and lignin distribution is consistent with that from tissue-dyeing with safranin O-fast green and (b) the distribution of cellulose, lignin, and starch is consistent with chemical images for characteristic wavelength at 1432, 1507, and 987 cm -1 , respectively, showing no interference from the other components analyzed. With the validation from biochemical images using characteristic wavelength and tissue-dyeing techniques, further semiquantitative analysis in local tissues based on fast NNLS was carried out, and the result showed that (a) the contents of cellulose in various tissues are very different, with most in parenchyma tissue and least in the epidermis and (b) during plant development, the fluctuation of each component in tissues follows nearly the same trend, especially within vascular bundles and parenchyma tissue. Thus, FTIR microspectroscopic imaging combined with suitable chemometric methods can be successfully applied to study chemical distributions within the internodes transverse sections of wheat straw, providing semiquantitative chemical information.

A first-in-man PET study of [18F]PSS232, a fluorinated ABP688 derivative for imaging metabotropic glutamate receptor subtype 5.

PubMed

Warnock, Geoffrey; Sommerauer, Michael; Mu, Linjing; Pla Gonzalez, Gloria; Geistlich, Susanne; Treyer, Valerie; Schibli, Roger; Buck, Alfred; Krämer, Stefanie D; Ametamey, Simon M

2018-06-01

Non-invasive imaging of metabotropic glutamate receptor 5 (mGlu 5 ) in the brain using PET is of interest in e.g., anxiety, depression, and Parkinson's disease. Widespread application of the most widely used mGlu 5 tracer, [ 11 C]ABP688, is limited by the short physical half-life of carbon-11. [ 18 F]PSS232 is a fluorinated analog with promising preclinical properties and high selectivity and specificity for mGlu 5 . In this first-in-man study, we evaluated the brain uptake pattern and kinetics of [ 18 F]PSS232 in healthy volunteers. [ 18 F]PSS232 PET was performed with ten healthy male volunteers aged 20-40 years. Seven of the subjects received a bolus injection and the remainder a bolus/infusion protocol. Cerebral blood flow was determined in seven subjects using [ 15 O]water PET. Arterial blood activity was measured using an online blood counter. Tracer kinetics were evaluated by compartment modeling and parametric maps were generated for both tracers. At 90 min post-injection, 59.2 ± 11.1% of total radioactivity in plasma corresponded to intact tracer. The regional first pass extraction fraction of [ 18 F]PSS232 ranged from 0.41 ± 0.06 to 0.55 ± 0.03 and brain distribution pattern matched that of [ 11 C]ABP688. Uptake kinetics followed a simple two-tissue compartment model. The volume of distribution of total tracer (V T , ml/cm 3 ) ranged from 1.18 ± 0.20 for white matter to 2.91 ± 0.51 for putamen. The respective mean distribution volume ratios (DVR) with cerebellum as the reference tissue were 0.88 ± 0.06 and 2.12 ± 0.10, respectively. The tissue/cerebellum ratios of a bolus/infusion protocol (30/70 dose ratio) were close to the DVR values. Brain uptake of [ 18 F]PSS232 matched the distribution of mGlu 5 and followed a two-tissue compartment model. The well-defined kinetics and the possibility to use reference tissue models, obviating the need for arterial blood sampling, make [ 18 F]PSS232 a promising fluorine-18 labeled radioligand for measuring mGlu 5 density in humans.

Biomagnification and tissue distribution of perfluoroalkyl substances (PFASs) in market-size rainbow trout (Oncorhynchus mykiss).

PubMed

Goeritz, Ina; Falk, Sandy; Stahl, Thorsten; Schäfers, Christoph; Schlechtriem, Christian

2013-09-01

The present study investigated the biomagnification potential as well as the substance and tissue-specific distribution of perfluoroalkyl substances (PFASs) in market-size rainbow trout (Oncorhynchus mykiss). Rainbow trout with an average body weight of 314 ± 21 g were exposed to perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and perfluorononanoic acid (PFNA) in the diet for 28 d. The accumulation phase was followed by a 28-d depuration phase, in which the test animals were fed with nonspiked trout feed. On days 0, 7, 14, 28, 31, 35, 42, and 56 of the present study, fish were sampled from the test basin for PFAS analysis. Biomagnification factors (BMFs) for all test compounds were determined based on a kinetic approach. Distribution factors were calculated for each test compound to illustrate the disposition of PFASs in rainbow trout after 28 d of exposure. Dietary exposure of market-size rainbow trout to PFASs did not result in biomagnification; BMF values were calculated as 0.42 for PFOS, >0.23 for PFNA, >0.18 for PFHxS, >0.04 for PFOA, and >0.02 for PFBS, which are below the biomagnification threshold of 1. Liver, blood, kidney, and skin were identified as the main target tissues for PFASs in market-size rainbow trout. Evidence was shown that despite relative low PFAS contamination, the edible parts of the fish (the fillet and skin) can significantly contribute to the whole-body burden. Copyright © 2013 SETAC.

Profiling of adrenocorticotropic hormone and arginine vasopressin in human pituitary gland and tumor thin tissue sections using droplet-based liquid-microjunction surface-sampling-HPLC-ESI-MS-MS.

PubMed

Kertesz, Vilmos; Calligaris, David; Feldman, Daniel R; Changelian, Armen; Laws, Edward R; Santagata, Sandro; Agar, Nathalie Y R; Van Berkel, Gary J

2015-08-01

Described here are the results from the profiling of the proteins arginine vasopressin (AVP) and adrenocorticotropic hormone (ACTH) from normal human pituitary gland and pituitary adenoma tissue sections, using a fully automated droplet-based liquid-microjunction surface-sampling-HPLC-ESI-MS-MS system for spatially resolved sampling, HPLC separation, and mass spectrometric detection. Excellent correlation was found between the protein distribution data obtained with this method and data obtained with matrix-assisted laser desorption/ionization (MALDI) chemical imaging analyses of serial sections of the same tissue. The protein distributions correlated with the visible anatomic pattern of the pituitary gland. AVP was most abundant in the posterior pituitary gland region (neurohypophysis), and ATCH was dominant in the anterior pituitary gland region (adenohypophysis). The relative amounts of AVP and ACTH sampled from a series of ACTH-secreting and non-secreting pituitary adenomas correlated with histopathological evaluation. ACTH was readily detected at significantly higher levels in regions of ACTH-secreting adenomas and in normal anterior adenohypophysis compared with non-secreting adenoma and neurohypophysis. AVP was mostly detected in normal neurohypophysis, as expected. This work reveals that a fully automated droplet-based liquid-microjunction surface-sampling system coupled to HPLC-ESI-MS-MS can be readily used for spatially resolved sampling, separation, detection, and semi-quantitation of physiologically-relevant peptide and protein hormones, including AVP and ACTH, directly from human tissue. In addition, the relative simplicity, rapidity, and specificity of this method support the potential of this basic technology, with further advancement, for assisting surgical decision-making. Graphical Abstract Mass spectrometry based profiling of hormones in human pituitary gland and tumor thin tissue sections.

Application of a time-resolved optical brain imager for monitoring cerebral oxygenation during carotid surgery.

PubMed

Kacprzak, Michal; Liebert, Adam; Staszkiewicz, Walerian; Gabrusiewicz, Andrzej; Sawosz, Piotr; Madycki, Grzegorz; Maniewski, Roman

2012-01-01

Recent studies have shown that time-resolved optical measurements of the head can estimate changes in the absorption coefficient with depth discrimination. Thus, changes in tissue oxygenation, which are specific to intracranial tissues, can be assessed using this advanced technique, and this method allows us to avoid the influence of changes to extracerebral tissue oxygenation on the measured signals. We report the results of time-resolved optical imaging that was carried out during carotid endarterectomy. This surgery remains the "gold standard" treatment for carotid stenosis, and intraoperative brain oxygenation monitoring may improve the safety of this procedure. A time-resolved optical imager was utilized within the operating theater. This instrument allows for the simultaneous acquisition of 32 distributions of the time-of-flight of photons at two wavelengths on both hemispheres. Analysis of the statistical moments of the measured distributions of the time-of-flight of photons was applied for estimating changes in the absorption coefficient as a function of depth. Time courses of changes in oxy- and deoxyhemoglobin of the extra- and intracerebral compartments during cross-clamping of the carotid arteries were obtained. A decrease in the oxyhemoglobin concentration and an increase in the deoxyhemoglobin concentrations were observed in a large area of the head. Large changes were observed in the hemisphere ipsilateral to the site of clamped carotid arteries. Smaller amplitude changes were noted at the contralateral site. We also found that changes in the hemoglobin signals, as estimated from intracerebral tissue, are very sensitive to clamping of the internal carotid artery, whereas its sensitivity to clamping of the external carotid artery is limited. We concluded that intraoperative multichannel measurements allow for imaging of brain tissue hemodynamics. However, when monitoring the brain during carotid surgery, a single-channel measurement may be sufficient.

Tissue distribution, excretion, and the metabolic pathway of 2,2',4,4',5-penta-chlorinated diphenylsulfide (CDPS-99) in ICR mice.

PubMed

Zeng, Xiaolan; Zhang, Xuesheng; Qin, Li; Wang, Zunyao

2015-09-15

The tissue distribution, excretion, and metabolic pathway of 2,2',4,4',5-penta-chlorinated diphenylsulfide (CDPS-99) in ICR mice were investigated after oral perfusion at 10mg/kg body weight (b.w.). Biological samples were extracted and separated and, for the first time, were determined by a novel, sensitive, and specific GC-MS method under the full scan and selected ion monitoring (SIM) modes. The results showed that the concentrations of CDPS-99 in the liver, kidneys, and serum reached a maximum after a one-day exposure and that the CDPS-99 concentration in the liver was the highest (3.43μg/g). The increase in the concentration of CDPS-99 in muscle, skin, and adipose tissue was slower, and the concentrations of CDPS-99 achieved their highest levels after 3 days of exposure. It was observed that the CDPS-99 concentration in adipose tissue was still very high (0.71μg/g) after 21 days of exposure, which suggested that CDPS-99 was able to accumulate in adipose tissue. In addition, mouse feces accounted for approximately 75% of the total gavage dose, indicating that CDPS-99 was mainly excreted via mouse feces. Metabolism analysis demonstrated that there were three possible metabolic pathways of CDPS-99 in mice: dechlorination reactions with the formation of tetra-CDPS and hydroxylation and oxidation reactions with the formation of OH-CDPS-99 and chlorinated diphenylsulfone. The present study will help to develop a better understanding of mammalian metabolism of CDPS-99. Copyright © 2015 Elsevier B.V. All rights reserved.

Artificial engineering of secondary lymphoid organs.

PubMed

Tan, Jonathan K H; Watanabe, Takeshi

2010-01-01

Secondary lymphoid organs such as spleen and lymph nodes are highly organized immune structures essential for the initiation of immune responses. They display distinct B cell and T cell compartments associated with specific stromal follicular dendritic cells and fibroblastic reticular cells, respectively. Interweaved through the parenchyma is a conduit system that distributes small antigens and chemokines directly to B and T cell zones. While most structural aspects between lymph nodes and spleen are common, the entry of lymphocytes, antigen-presenting cells, and antigen into lymphoid tissues is regulated differently, reflecting the specialized functions of each organ in filtering either lymph or blood. The overall organization of lymphoid tissue is vital for effective antigen screening and recognition, and is a feature which artificially constructed lymphoid organoids endeavor to replicate. Synthesis of artificial lymphoid tissues is an emerging field that aims to provide therapeutic application for the treatment of severe infection, cancer, and age-related involution of secondary lymphoid tissues. The development of murine artificial lymphoid tissues has benefited greatly from an understanding of organogenesis of lymphoid organs, which has delineated cellular and molecular elements essential for the recruitment and organization of lymphocytes into lymphoid structures. Here, the field of artificial lymphoid tissue engineering is considered including elements of lymphoid structure and development relevant to organoid synthesis. (c) 2010 Elsevier Inc. All rights reserved.

Cell lineage tracing during Xenopus tail regeneration.

PubMed

Gargioli, Cesare; Slack, Jonathan M W

2004-06-01

The tail of the Xenopus tadpole will regenerate following amputation, and all three of the main axial structures - the spinal cord, the notochord and the segmented myotomes - are found in the regenerated tail. We have investigated the cellular origin of each of these three tissue types during regeneration. We produced Xenopus laevis embryos transgenic for the CMV (Simian Cytomegalovirus) promoter driving GFP (Green Fluorescent Protein) ubiquitously throughout the embryo. Single tissues were then specifically labelled by making grafts at the neurula stage from transgenic donors to unlabelled hosts. When the hosts have developed to tadpoles, they carry a region of the appropriate tissue labelled with GFP. These tails were amputated through the labelled region and the distribution of labelled cells in the regenerate was followed. We also labelled myofibres using the Cre-lox method. The results show that the spinal cord and the notochord regenerate from the same tissue type in the stump, with no labelling of other tissues. In the case of the muscle, we show that the myofibres of the regenerate arise from satellite cells and not from the pre-existing myofibres. This shows that metaplasia between differentiated cell types does not occur, and that the process of Xenopus tail regeneration is more akin to tissue renewal in mammals than to urodele tail regeneration.

Design considerations and challenges for mechanical stretch bioreactors in tissue engineering.

PubMed

Lei, Ying; Ferdous, Zannatul

2016-05-01

With the increase in average life expectancy and growing aging population, lack of functional grafts for replacement surgeries has become a severe problem. Engineered tissues are a promising alternative to this problem because they can mimic the physiological function of the native tissues and be cultured on demand. Cyclic stretch is important for developing many engineered tissues such as hearts, heart valves, muscles, and bones. Thus a variety of stretch bioreactors and corresponding scaffolds have been designed and tested to study the underlying mechanism of tissue formation and to optimize the mechanical conditions applied to the engineered tissues. In this review, we look at various designs of stretch bioreactors and common scaffolds and offer insights for future improvements in tissue engineering applications. First, we summarize the requirements and common configuration of stretch bioreactors. Next, we present the features of different actuating and motion transforming systems and their applications. Since most bioreactors must measure detailed distributions of loads and deformations on engineered tissues, techniques with high accuracy, precision, and frequency have been developed. We also cover the key points in designing culture chambers, nutrition exchanging systems, and regimens used for specific tissues. Since scaffolds are essential for providing biophysical microenvironments for residing cells, we discuss materials and technologies used in fabricating scaffolds to mimic anisotropic native tissues, including decellularized tissues, hydrogels, biocompatible polymers, electrospinning, and 3D bioprinting techniques. Finally, we present the potential future directions for improving stretch bioreactors and scaffolds. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:543-553, 2016. © 2016 American Institute of Chemical Engineers.

Easy performance of 6-color confocal immunofluorescence with 4-laser line microscopes.

PubMed

Eissing, Nathalie; Heger, Lukas; Baranska, Anna; Cesnjevar, Robert; Büttner-Herold, Maike; Söder, Stephan; Hartmann, Arndt; Heidkamp, Gordon F; Dudziak, Diana

2014-09-01

Confocal laser scanning microscopy is an advanced technique for imaging tissue samples in vitro and in vivo at high optical resolution. The development of new fluorochrome variants do not only make it possible to perform multicolor flow cytometry of single cells, but in combination with high resolution laser scanning systems also to investigate the distribution of cells in lymphoid tissues by confocal immunofluorescence analyses, thus allowing the distinction of various cell populations directly in the tissue. Here, we provide a protocol for the visualization of at least six differently fluorochrome-labeled antibodies at the same time using a conventional confocal laser scanning microscope with four laser lines (405 nm, 488 nm, 555 nm, and 639 nm laser wavelength) in both murine and human tissue samples. We further demonstrate that compensation correction algorithms are not necessary to reduce spillover of fluorochromes into other channels when the used fluorochromes are combined according to their specific emission bands and the varying Stokes shift for co-excited fluorochromes with the same laser line. Copyright © 2014 Elsevier B.V. All rights reserved.

Sensing inhomogeneous mechanical properties of human corneal Descemet's membrane with AFM nano-indentation.

PubMed

Di Mundo, Rosa; Recchia, Giuseppina; Parekh, Mohit; Ruzza, Alessandro; Ferrari, Stefano; Carbone, Giuseppe

2017-10-01

The paper describes a highly space-resolved characterization of the surface mechanical properties of the posterior human corneal layer (Descemet's membrane). This has been accomplished with Atomic Force Microscopy (AFM) nano-indentation by using a probe with a sharp tip geometry. Results indicate that the contact with this biological tissue in liquid occurs with no (or very low) adhesion. More importantly, under the same operating conditions, a broad distribution of penetration depth can be measured on different x-y positions of the tissue surface, indicating a high inhomogeneity of surface stiffness, not yet clearly reported in the literature. An important contribution to such inhomogeneity should be ascribed to the discontinuous nature of the collagen/proteoglycans fibers matrix tissue, as can be imaged by AFM when the tissue is semi-dry. Using classical contact mechanics calculations adapted to the specific geometry of the tetrahedral tip it has been found that the elastic modulus E of the material in the very proximity of the surface ranges from 0.23 to 2.6 kPa. Copyright © 2017 Elsevier Ltd. All rights reserved.

Current advances in mathematical modeling of anti-cancer drug penetration into tumor tissues.

PubMed

Kim, Munju; Gillies, Robert J; Rejniak, Katarzyna A

2013-11-18

Delivery of anti-cancer drugs to tumor tissues, including their interstitial transport and cellular uptake, is a complex process involving various biochemical, mechanical, and biophysical factors. Mathematical modeling provides a means through which to understand this complexity better, as well as to examine interactions between contributing components in a systematic way via computational simulations and quantitative analyses. In this review, we present the current state of mathematical modeling approaches that address phenomena related to drug delivery. We describe how various types of models were used to predict spatio-temporal distributions of drugs within the tumor tissue, to simulate different ways to overcome barriers to drug transport, or to optimize treatment schedules. Finally, we discuss how integration of mathematical modeling with experimental or clinical data can provide better tools to understand the drug delivery process, in particular to examine the specific tissue- or compound-related factors that limit drug penetration through tumors. Such tools will be important in designing new chemotherapy targets and optimal treatment strategies, as well as in developing non-invasive diagnosis to monitor treatment response and detect tumor recurrence.

Early short-term treatment with neutralizing human monoclonal antibodies halts SHIV infection in infant macaques.

PubMed

Hessell, Ann J; Jaworski, J Pablo; Epson, Erin; Matsuda, Kenta; Pandey, Shilpi; Kahl, Christoph; Reed, Jason; Sutton, William F; Hammond, Katherine B; Cheever, Tracy A; Barnette, Philip T; Legasse, Alfred W; Planer, Shannon; Stanton, Jeffrey J; Pegu, Amarendra; Chen, Xuejun; Wang, Keyun; Siess, Don; Burke, David; Park, Byung S; Axthelm, Michael K; Lewis, Anne; Hirsch, Vanessa M; Graham, Barney S; Mascola, John R; Sacha, Jonah B; Haigwood, Nancy L

2016-04-01

Prevention of mother-to-child transmission (MTCT) of HIV remains a major objective where antenatal care is not readily accessible. We tested HIV-1-specific human neutralizing monoclonal antibodies (NmAbs) as a post-exposure therapy in an infant macaque model for intrapartum MTCT. One-month-old rhesus macaques were inoculated orally with the simian-human immunodeficiency virus SHIVSF162P3. On days 1, 4, 7 and 10 after virus exposure, we injected animals subcutaneously with NmAbs and quantified systemic distribution of NmAbs in multiple tissues within 24 h after antibody administration. Replicating virus was found in multiple tissues by day 1 in animals that were not treated. All NmAb-treated macaques were free of virus in blood and tissues at 6 months after exposure. We detected no anti-SHIV T cell responses in blood or tissues at necropsy, and no virus emerged after CD8(+) T cell depletion. These results suggest that early passive immunotherapy can eliminate early viral foci and thereby prevent the establishment of viral reservoirs.

Stem cell bioprinting for applications in regenerative medicine.

PubMed

Tricomi, Brad J; Dias, Andrew D; Corr, David T

2016-11-01

Many regenerative medicine applications seek to harness the biologic power of stem cells in architecturally complex scaffolds or microenvironments. Traditional tissue engineering methods cannot create such intricate structures, nor can they precisely control cellular position or spatial distribution. These limitations have spurred advances in the field of bioprinting, aimed to satisfy these structural and compositional demands. Bioprinting can be defined as the programmed deposition of cells or other biologics, often with accompanying biomaterials. In this concise review, we focus on recent advances in stem cell bioprinting, including performance, utility, and applications in regenerative medicine. More specifically, this review explores the capability of bioprinting to direct stem cell fate, engineer tissue(s), and create functional vascular networks. Furthermore, the unique challenges and concerns related to bioprinting living stem cells, such as viability and maintaining multi- or pluripotency, are discussed. The regenerative capacity of stem cells, when combined with the structural/compositional control afforded by bioprinting, provides a unique and powerful tool to address the complex demands of tissue engineering and regenerative medicine applications. © 2016 New York Academy of Sciences.

Alternative Polyadenylation Directs Tissue-Specific miRNA Targeting in Caenorhabditis elegans Somatic Tissues

PubMed Central

Blazie, Stephen M.; Geissel, Heather C.; Wilky, Henry; Joshi, Rajan; Newbern, Jason; Mangone, Marco

2017-01-01

mRNA expression dynamics promote and maintain the identity of somatic tissues in living organisms; however, their impact in post-transcriptional gene regulation in these processes is not fully understood. Here, we applied the PAT-Seq approach to systematically isolate, sequence, and map tissue-specific mRNA from five highly studied Caenorhabditis elegans somatic tissues: GABAergic and NMDA neurons, arcade and intestinal valve cells, seam cells, and hypodermal tissues, and studied their mRNA expression dynamics. The integration of these datasets with previously profiled transcriptomes of intestine, pharynx, and body muscle tissues, precisely assigns tissue-specific expression dynamics for 60% of all annotated C. elegans protein-coding genes, providing an important resource for the scientific community. The mapping of 15,956 unique high-quality tissue-specific polyA sites in all eight somatic tissues reveals extensive tissue-specific 3′untranslated region (3′UTR) isoform switching through alternative polyadenylation (APA) . Almost all ubiquitously transcribed genes use APA and harbor miRNA targets in their 3′UTRs, which are commonly lost in a tissue-specific manner, suggesting widespread usage of post-transcriptional gene regulation modulated through APA to fine tune tissue-specific protein expression. Within this pool, the human disease gene C. elegans orthologs rack-1 and tct-1 use APA to switch to shorter 3′UTR isoforms in order to evade miRNA regulation in the body muscle tissue, resulting in increased protein expression needed for proper body muscle function. Our results highlight a major positive regulatory role for APA, allowing genes to counteract miRNA regulation on a tissue-specific basis. PMID:28348061

Alternative Polyadenylation Directs Tissue-Specific miRNA Targeting in Caenorhabditis elegans Somatic Tissues.

PubMed

Blazie, Stephen M; Geissel, Heather C; Wilky, Henry; Joshi, Rajan; Newbern, Jason; Mangone, Marco

2017-06-01

mRNA expression dynamics promote and maintain the identity of somatic tissues in living organisms; however, their impact in post-transcriptional gene regulation in these processes is not fully understood. Here, we applied the PAT-Seq approach to systematically isolate, sequence, and map tissue-specific mRNA from five highly studied Caenorhabditis elegans somatic tissues: GABAergic and NMDA neurons, arcade and intestinal valve cells, seam cells, and hypodermal tissues, and studied their mRNA expression dynamics. The integration of these datasets with previously profiled transcriptomes of intestine, pharynx, and body muscle tissues, precisely assigns tissue-specific expression dynamics for 60% of all annotated C. elegans protein-coding genes, providing an important resource for the scientific community. The mapping of 15,956 unique high-quality tissue-specific polyA sites in all eight somatic tissues reveals extensive tissue-specific 3'untranslated region (3'UTR) isoform switching through alternative polyadenylation (APA) . Almost all ubiquitously transcribed genes use APA and harbor miRNA targets in their 3'UTRs, which are commonly lost in a tissue-specific manner, suggesting widespread usage of post-transcriptional gene regulation modulated through APA to fine tune tissue-specific protein expression. Within this pool, the human disease gene C. elegans orthologs rack-1 and tct-1 use APA to switch to shorter 3'UTR isoforms in order to evade miRNA regulation in the body muscle tissue, resulting in increased protein expression needed for proper body muscle function. Our results highlight a major positive regulatory role for APA, allowing genes to counteract miRNA regulation on a tissue-specific basis. Copyright © 2017 Blazie et al.

Three-Dimensional Optical Mapping of Nanoparticle Distribution in Intact Tissues.

PubMed

Sindhwani, Shrey; Syed, Abdullah Muhammad; Wilhelm, Stefan; Glancy, Dylan R; Chen, Yih Yang; Dobosz, Michael; Chan, Warren C W

2016-05-24

The role of tissue architecture in mediating nanoparticle transport, targeting, and biological effects is unknown due to the lack of tools for imaging nanomaterials in whole organs. Here, we developed a rapid optical mapping technique to image nanomaterials in intact organs ex vivo and in three-dimensions (3D). We engineered a high-throughput electrophoretic flow device to simultaneously transform up to 48 tissues into optically transparent structures, allowing subcellular imaging of nanomaterials more than 1 mm deep into tissues which is 25-fold greater than current techniques. A key finding is that nanomaterials can be retained in the processed tissue by chemical cross-linking of surface adsorbed serum proteins to the tissue matrix, which enables nanomaterials to be imaged with respect to cells, blood vessels, and other structures. We developed a computational algorithm to analyze and quantitatively map nanomaterial distribution. This method can be universally applied to visualize the distribution and interactions of materials in whole tissues and animals including such applications as the imaging of nanomaterials, tissue engineered constructs, and biosensors within their intact biological environment.

Bone-Inspired Spatially Specific Piezoelectricity Induces Bone Regeneration

PubMed Central

Yu, Peng; Ning, Chengyun; Zhang, Yu; Tan, Guoxin; Lin, Zefeng; Liu, Shaoxiang; Wang, Xiaolan; Yang, Haoqi; Li, Kang; Yi, Xin; Zhu, Ye; Mao, Chuanbin

2017-01-01

The extracellular matrix of bone can be pictured as a material made of parallel interspersed domains of fibrous piezoelectric collagenous materials and non-piezoelectric non-collagenous materials. To mimic this feature for enhanced bone regeneration, a material made of two parallel interspersed domains, with higher and lower piezoelectricity, respectively, is constructed to form microscale piezoelectric zones (MPZs). The MPZs are produced using a versatile and effective laser-irradiation technique in which K0.5Na0.5NbO3 (KNN) ceramics are selectively irradiated to achieve microzone phase transitions. The phase structure of the laser-irradiated microzones is changed from a mixture of orthorhombic and tetragonal phases (with higher piezoelectricity) to a tetragonal dominant phase (with lower piezoelectricity). The microzoned piezoelectricity distribution results in spatially specific surface charge distribution, enabling the MPZs to bear bone-like microscale electric cues. Hence, the MPZs induce osteogenic differentiation of stem cells in vitro and bone regeneration in vivo even without being seeded with stem cells. The concept of mimicking the spatially specific piezoelectricity in bone will facilitate future research on the rational design of tissue regenerative materials. PMID:28900517

Tissue distribution of a novel neurotensin-degrading metallopeptidase. An immunological approach using monospecific polyclonal antibodies.

PubMed

Checler, F; Barelli, H; Vincent, J P

1989-01-15

A monospecific polyclonal antiserum was raised against a recently purified rat brain neurotensin-degrading metallopeptidase. The purified IgG fraction immunoprecipitated the peptidase and inhibited its proteolytic activity. Western blot analyses revealed that the immune fraction recognizes only one protein in rat brain homogenates, and this corresponds closely to the purified enzyme. The IgG displayed a restricted specificity towards the peptidase from murine origin. In the rat, the neurotensin-degrading enzyme was widely distributed throughout peripheral organs with the noticeable exception of the duodenum. In addition, the peptidase was detected in various cell lines or membrane preparations of neural or extraneural origin in which it had been previously characterized by means of biochemical methods. In light of this widespread distribution, the putative role of the peptidase in the metabolism of neuropeptides is discussed.

Novel insights into structure–function mechanism and tissue-specific expression profiling of full-length dxr gene from Cymbopogon winterianus

PubMed Central

Devi, Kamalakshi; Dehury, Budheswar; Phukon, Munmi; Modi, Mahendra Kumar; Sen, Priyabrata

2015-01-01

The 1-deoxy-d-xylulose-5-phosphate reductoisomerase (DXR; EC1.1.1.267), an NADPH-dependent reductase, plays a pivotal role in the methylerythritol 4-phosphate pathway (MEP), in the conversion of 1-deoxy-d-xylulose-5-phosphate (DXP) into MEP. The sheath and leaf of citronella (Cymbopogon winterianus) accumulates large amount of terpenes and sesquiterpenes with proven medicinal value and economic uses. Thus, sequencing of full length dxr gene and its characterization seems to be a valuable resource in metabolic engineering to alter the flux of isoprenoid active ingredients in plants. In this study, full length DXR from citronella was characterized through in silico and tissue-specific expression studies to explain its structure–function mechanism, mode of cofactor recognition and differential expression. The modelled DXR has a three-domain architecture and its active site comprised of a cofactor (NADPH) binding pocket and the substrate-binding pocket. Molecular dynamics simulation studies indicated that DXR model retained most of its secondary structure during 10 ns simulation in aqueous solution. The modelled DXR superimposes well with its closest structural homolog but subtle variations in the charge distribution over the cofactor recognition site were noticed. Molecular docking study revealed critical residues aiding tight anchoring NADPH within the active pocket of DXR. Tissue-specific differential expression analysis using semi-quantitative RT-PCR and qRT-PCR in various tissues of citronella plant revealed distinct differential expression of DXR. To our knowledge, this is the first ever report on DXR from the important medicinal plant citronella and further characterization of this gene will open up better avenues for metabolic engineering of secondary metabolite pathway genes from medicinal plants in the near future. PMID:25941629

Tissue-specific root ion profiling reveals essential roles of the CAX and ACA calcium transport systems in response to hypoxia in Arabidopsis

PubMed Central

Wang, Feifei; Chen, Zhong-Hua; Liu, Xiaohui; Colmer, Timothy David; Zhou, Meixue; Shabala, Sergey

2016-01-01

Waterlogging is a major abiotic stress that limits the growth of plants. The crucial role of Ca2+ as a second messenger in response to abiotic and biotic stimuli has been widely recognized in plants. However, the physiological and molecular mechanisms of Ca2+ distribution within specific cell types in different root zones under hypoxia is poorly understood. In this work, whole-plant physiological and tissue-specific Ca2+ changes were studied using several ACA (Ca2+-ATPase) and CAX (Ca2+/proton exchanger) knock-out Arabidopsis mutants subjected to waterlogging treatment. In the wild-type (WT) plants, several days of hypoxia decreased the expression of ACA8, CAX4, and CAX11 by 33% and 50% compared with the control. The hypoxic treatment also resulted in an up to 11-fold tissue-dependent increase in Ca2+ accumulation in root tissues as revealed by confocal microscopy. The increase was much higher in stelar cells in the mature zone of Arabidopsis mutants with loss of function for ACA8, ACA11, CAX4, and CAX11. In addition, a significantly increased Ca2+ concentration was found in the cytosol of stelar cells in the mature zone after hypoxic treatment. Three weeks of waterlogging resulted in dramatic loss of shoot biomass in cax11 plants (67% loss in shoot dry weight), while in the WT and other transport mutants this decline was only 14–22%. These results were also consistent with a decline in leaf chlorophyll fluorescence (F v/F m). It is suggested that CAX11 plays a key role in maintaining cytosolic Ca2+ homeostasis and/or signalling in root cells under hypoxic conditions. PMID:26889007

The fate of arsenic, cadmium and lead in Typha latifolia: a case study on the applicability of micro-PIXE in plant ionomics.

PubMed

Lyubenova, Lyudmila; Pongrac, Paula; Vogel-Mikuš, Katarina; Mezek, Gašper Kukec; Vavpetič, Primož; Grlj, Nataša; Regvar, Marjana; Pelicon, Primož; Schröder, Peter

2013-03-15

Understanding the uptake, accumulation and distribution of toxic elements in plants is crucial to the design of effective phytoremediation strategies, especially in the case of complex multi-element pollution. Using micro-proton induced X-ray emission, the spatial distribution of Na, Mg, Al, Si, P, S, Cl, K, Ca, Mn, Fe, Zn, As, Br, Rb, Sr, Cd and Pb have been quantitatively resolved in roots and rhizomes of an obligate wetland plant species, Typha latifolia, treated with a mixture of 100 μM each of As, Cd and Pb, together. The highest concentrations of As, Cd and Pb were found in the roots of the T. latifolia, with tissue-specific distributions. The As was detected in the root rhizodermis, and in the rhizome the majority of the As was within the vascular tissues, which indicates the high mobility of As within T. latifolia. The Cd was detected in the root exodermis, and in the vascular bundle and epidermis of the rhizome. The highest Pb concentrations were detected in the root rhizodermis and exodermis, and in the epidermis of the rhizome. These data represent an essential step in the resolution of fundamental questions in plant ionomics. Copyright © 2013 Elsevier B.V. All rights reserved.

Light distribution properties in spinal cord for optogenetic stimulation (Conference Presentation)

NASA Astrophysics Data System (ADS)

GÄ secka, Alicja; Bahdine, Mohamed; Lapointe, Nicolas; Rioux, Veronique; Perez-Sanchez, Jimena; Bonin, Robert P.; De Koninck, Yves; Côté, Daniel

2016-03-01

Optogenetics is currently one of the most popular technique in neuroscience. It enables cell-selective and temporally-precise control of neuronal activity. Good spatial control of the stimulated area and minimized tissue damage requires a specific knowledge about light scattering properties. Light propagation in cell cultures and brain tissue is relatively well documented and allows for a precise and reliable delivery of light to the neurons. In spinal cord, light must pass through highly organized white matter before reaching cell bodies present in grey matter, this heterogenous structure makes it difficult to predict the propagation pattern. In this work we investigate the light distribution properties through mouse and monkey spinal cord. The light propagation depends on a fibers orientation, leading to less deep penetration profile in the direction perpendicular to the fibers and lower attenuation in the direction parallel to the fibers. Additionally, the use of different illumination wavelengths results in variations of the attenuation coefficient. Next, we use Monte-Carlo simulation to study light transport. The model gives a full 3-D simulation of light distribution in spinal cord and takes into account different scattering properties related to the fibers orientation. These studies are important to estimate the minimum optical irradiance required at the fiber tip to effectively excite the optogenetic proteins in a desired region of spinal cord.

Human body epigenome maps reveal noncanonical DNA methylation variation.

PubMed

Schultz, Matthew D; He, Yupeng; Whitaker, John W; Hariharan, Manoj; Mukamel, Eran A; Leung, Danny; Rajagopal, Nisha; Nery, Joseph R; Urich, Mark A; Chen, Huaming; Lin, Shin; Lin, Yiing; Jung, Inkyung; Schmitt, Anthony D; Selvaraj, Siddarth; Ren, Bing; Sejnowski, Terrence J; Wang, Wei; Ecker, Joseph R

2015-07-09

Understanding the diversity of human tissues is fundamental to disease and requires linking genetic information, which is identical in most of an individual's cells, with epigenetic mechanisms that could have tissue-specific roles. Surveys of DNA methylation in human tissues have established a complex landscape including both tissue-specific and invariant methylation patterns. Here we report high coverage methylomes that catalogue cytosine methylation in all contexts for the major human organ systems, integrated with matched transcriptomes and genomic sequence. By combining these diverse data types with each individuals' phased genome, we identified widespread tissue-specific differential CG methylation (mCG), partially methylated domains, allele-specific methylation and transcription, and the unexpected presence of non-CG methylation (mCH) in almost all human tissues. mCH correlated with tissue-specific functions, and using this mark, we made novel predictions of genes that escape X-chromosome inactivation in specific tissues. Overall, DNA methylation in several genomic contexts varies substantially among human tissues.

Quantification of HCV RNA in Liver Tissue by bDNA Assay.

PubMed

Dailey, P J; Collins, M L; Urdea, M S; Wilber, J C

1999-01-01

With this statement, Sherlock and Dooley have described two of the three major challenges involved in quantitatively measuring any analyte in tissue samples: the distribution of the analyte in the tissue; and the standard of reference, or denominator, with which to make comparisons between tissue samples. The third challenge for quantitative measurement of an analyte in tissue is to ensure reproducible and quantitative recovery of the analyte on extraction from tissue samples. This chapter describes a method that can be used to measure HCV RNA quantitatively in liver biopsy and tissue samples using the bDNA assay. All three of these challenges-distribution, denominator, and recovery-apply to the measurement of HCV RNA in liver biopsies.