Spatial and Temporal Control of Cavitation Allows High In Vitro Transfection Efficiency in the Absence of Transfection Reagents or Contrast Agents.

PubMed

Chettab, Kamel; Roux, Stéphanie; Mathé, Doriane; Cros-Perrial, Emeline; Lafond, Maxime; Lafon, Cyril; Dumontet, Charles; Mestas, Jean-Louis

2015-01-01

Sonoporation using low-frequency high-pressure ultrasound (US) is a non-viral approach for in vitro and in vivo gene delivery. In this study, we developed a new sonoporation device designed for spatial and temporal control of ultrasound cavitation. The regulation system incorporated in the device allowed a real-time control of the cavitation level during sonoporation. This device was evaluated for the in vitro transfection efficiency of a plasmid coding for Green Fluorescent Protein (pEGFP-C1) in adherent and non-adherent cell lines. The transfection efficiency of the device was compared to those observed with lipofection and nucleofection methods. In both adherent and non-adherent cell lines, the sonoporation device allowed high rate of transfection of pEGFP-C1 (40-80%), as determined by flow cytometry analysis of GFP expression, along with a low rate of mortality assessed by propidium iodide staining. The transfection efficiency and toxicity of sonoporation on the non-adherent cell lines Jurkat and K562 were similar to those of nucleofection, while these two cell lines were resistant to transfection by lipofection. Moreover, sonoporation was used to produce three stably transfected human lymphoma and leukemia lines. Significant transfection efficiency was also observed in two fresh samples of human acute myeloid leukemia cells. In conclusion, we developed a user-friendly and cost-effective ultrasound device, well adapted for routine in vitro high-yield transfection experiments and which does not require the use of any transfection reagent or gas micro-bubbles.

Glass fibre-reinforced composite laced with chlorhexidine digluconate and yeast adhesion.

PubMed

Waltimo, T; Luo, G; Samaranayake, L P; Vallittu, P K

2004-02-01

The aim of this study was to lace dental glass fibre reinforced composite (FRC) prepreg with chlorhexidine digluconate and to examine the adherence of common oral fungal pathogen Candida albicans to FRC made of the prepreg. Four different test and control material groups each comprising 16 test specimens ((5.0 x 5.0 x 0.8) mm3) each were used as substrates for C. albicans adherence. A porous polymer pre-impregnated woven glass fibre prepreg was laced with solution of chlorhexidine gluconate and it was used with autopolymerized denture base polymer to fabricate FRC test specimens. Control group (Group 1) consisted of FRC test specimens stored in water. In Group 2, the test specimens were stored in 10% chlorhexidine digluconate solution for 24 h. Group 3 consisted of specimens fabricated using such fibre reinforcements which were pre-soaked in 20% chlorhexidine digluconate and dried before preparation with denture base resin, and followed by storage of the specimens in water. Group 4 was similar to Group 3 but instead of water storage the specimens were immersed in 10% chlorhexidine digluconate for 24 h. For the candidal adhesion assay the test and control specimens were incubated in standardized suspensions of four different strains of C. albicans, rinsed and prepared for light-microscopy. The mean number of adherent cells in each group was counted microscopically and analysed statistically. There were significantly (P < 0.05) more adherent C. albicans cells found in Group 1 than in the other three groups which did not differ significantly from each other. The lowest numbers of adherent cells were found in Group 3. Pretreating the porous polymer pre-impregnated glass fibre reinforcement with chlorhexidine digluconate result in reduction in the number of adherent yeast cells on the surface FRC material.

Adherence to Mediterranean-style dietary pattern and risk of esophageal squamous cell carcinoma: a case-control study in Iran

USDA-ARS?s Scientific Manuscript database

The benefit of adherence to a Mediterranean-style dietary pattern in relation to the risk of esophageal squamous cell carcinoma (ESCC) has not been investigated among non-Mediterranean high-risk populations. The objective of the present study was to examine the association of compliance with the Med...

Live-cell calcium imaging of adherent and non-adherent GL261 cells reveals phenotype-dependent differences in drug responses.

PubMed

Strong, Averey D; Daniels, Richard L

2017-08-02

The tumor-derived GL261 cell line is used as a model for studying glioblastoma and other high-grade gliomas, and can be cultured adherently or as free-floating aggregates known as neurospheres. These different culture conditions give rise to distinct phenotypes, with increased tumorigenicity displayed by neurosphere-cultured cells. An important technique for understanding GL261 pathobiology is live cell fluorescent imaging of intracellular calcium. However, live cell imaging of GL261 neurospheres presents a technical challenge, as experimental manipulations where drugs are added to the extracellular media cause the cells to move during analysis. Here we present a method to immobilize GL261 neurospheres with low melting point agarose for calcium imaging using the fluorescent calcium sensor fura-2. GL261 cells were obtained from the NCI-Frederick Cancer Research Tumor Repository and cultured as adherent cells or induced to form neurospheres by placing freshly trypsinized cells into serum-free media containing fibroblast growth factor 2, epidermal growth factor, and B-27 supplement. Prior to experiments, adherent cells were loaded with fura-2 and cultured on 8-well chamber slides. Non-adherent neurospheres were first loaded with fura-2, placed in droplets onto an 8-well chamber slide, and finally covered with a thin layer of low melting point agarose to immobilize the cells. Ratiometric pseudocolored images were obtained during treatment with ATP, capsaicin, or vehicle control. Cells were marked as responsive if fluorescence levels increased more than 30% above baseline. Differences between treatment groups were tested using Student's t-tests and one-way ANOVA. We found that cellular responses to pharmacological treatments differ based on cellular phenotype. Adherent cells and neurospheres both responded to ATP with a rise in intracellular calcium. Notably, capsaicin treatment led to robust responses in GL261 neurospheres but not adherent cells. We demonstrate the use of low melting point agarose for immobilizing GL261 cells, a method that is broadly applicable to any cell type cultured in suspension, including acutely trypsinized cells and primary tumor cells. Our results indicate that it is important to consider GL261 phenotype (adherent or neurosphere) when interpreting data regarding physiological responses to experimental compounds.

A quality-by-design approach to risk reduction and optimization for human embryonic stem cell cryopreservation processes.

PubMed

Mitchell, Peter D; Ratcliffe, Elizabeth; Hourd, Paul; Williams, David J; Thomas, Robert J

2014-12-01

It is well documented that cryopreservation and resuscitation of human embryonic stem cells (hESCs) is complex and ill-defined, and often suffers poor cell recovery and increased levels of undesirable cell differentiation. In this study we have applied Quality-by-Design (QbD) concepts to the critical processes of slow-freeze cryopreservation and resuscitation of hESC colony cultures. Optimized subprocesses were linked together to deliver a controlled complete process. We have demonstrated a rapid, high-throughput, and stable system for measurement of cell adherence and viability as robust markers of in-process and postrecovery cell state. We observed that measurement of adherence and viability of adhered cells at 1 h postseeding was predictive of cell proliferative ability up to 96 h in this system. Application of factorial design defined the operating spaces for cryopreservation and resuscitation, critically linking the performance of these two processes. Optimization of both processes resulted in enhanced reattachment and post-thaw viability, resulting in substantially greater recovery of cryopreserved, pluripotent cell colonies. This study demonstrates the importance of QbD concepts and tools for rapid, robust, and low-risk process design that can inform manufacturing controls and logistics.

Transduction of beta3 integrin subunit cDNA confers on human keratinocytes the ability to adhere to gelatin.

PubMed

Kubo, Miyoko; Clark, Richard A F; Katz, Anne B; Taichman, Lorne B; Jin, Zaishun; Zhao, Ying; Moriguchi, Takahiko

2007-04-01

alphavbeta3 is a multiligand integrin receptor that interacts with fibrinogen (FG), fibrin (FB), fibronectin (FN), vitronectin (VN), and denatured collagen. We previously reported that cultured normal human keratinocytes, like in vivo keratinocytes, do not express alphavbeta3 on the cell surface, and do not adhere to and migrate on FG and FB. Furthermore, we reported that human keratinocytes transduced with beta3 integrin subunit cDNA by a retrovirus-mediated transduction method express alphavbeta3 on the cell surface and adhere to FG, FB, FN, and VN significantly compared with beta-galactosidase (beta-gal) cDNA-transduced keratinocytes (control). In this study, we determined whether these beta3 integrin subunit cDNA-transduced keratinocytes or normal human keratinocytes adhere to denatured collagen (gelatin) using a 1 h cell adhesion assay. beta3 cDNA-transduced keratinocytes adhered to gelatin, whereas no significant adhesion was observed with the control cells (beta-gal cDNA-transduced keratinocytes and normal human keratinocytes). The adhesion to gelatin was inhibited by LM609, a monoclonal antibody to alphavbeta3, and RGD peptides but not by normal mouse IgG1 nor RGE peptides. Thus, transduction of beta3 integrin subunit cDNA confers on human keratinocytes the ability to adhere to denatured collagen (gelatin) as well as to FG, FB, VN, and FN. Otherwise, normal human keratinocytes do not adhere to gelatin. These data support the idea that beta3 cDNA-transduced human keratinocytes can be a good material for cultured epithelium to achieve better take rate with acute or chronic wounds, in which FG, FB, and denatured collagen are abundantly present.

In vitro biological evaluation of beta-TCP/HDPE--A novel orthopedic composite: a survey using human osteoblast and fibroblast bone cells.

PubMed

Homaeigohar, S Sh; Shokrgozar, M A; Khavandi, A; Sadi, A Yari

2008-02-01

Beta-tricalcium phosphate reinforced high density polyethylene (beta-TCP/HDPE) was prepared to simulate bone composition and to study its capacity to act as bone tissue. This material was produced by replacing the mineral component and collagen soft tissue of the bone with beta-TCP and HDPE, respectively. The biocompatibility of the composite samples with different volume fractions of TCP (20, 30 and 40 vol %) was examined in vitro using two osteoblast cell lines G-292 and Saos-2, and also a type of fibroblast cell isolated from bone tissue, namely human bone fibroblast (HBF) by proliferation, and cell adhesion assays. Cell-material interaction with the surface of the composite samples was examined by scanning electron microscopy (SEM). The effect of beta-TCP/HDPE on the behavior of osteoblast and fibroblast cells was compared with those of composite and negative control samples; polyethylene (PE) and tissue culture polystyrene (TPS), respectively. In general, the results showed that the composite samples containing beta-TCP as reinforcement supported a higher rate of proliferation by various bone cells after 3, 7, and 14 days of incubation compared to the composite control sample. Furthermore, more osteoblast cells were attached to the surface of the composite samples when compared to the composite control samples after the above incubation periods (p < 0.05), while in the case of HBF an equal or even higher number of cells adhered to PE was observed. The number of adhered osteoblast cells was almost equal and in some days even higher than the number of adhered cells on negative control sample, while in the case of fibroblast this difference was significantly higher than TPS (p < 0.05). Adhered cells presented a normal morphology by SEM and many of the cells were observed to be undergoing cell division. These findings indicate that beta-TCP/HDPE composites are biocompatible, nontoxic, and act to stimulate proliferation and adhesion of the cells, whether osteoblast or fibroblast. (c) 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008.

The suppression of mitogen responses associated with resistance to experimental autoimmune encephalomyelitis requires adherent and T cells.

PubMed

Lyman, W D; Brosnan, C F; Kadish, A S; Raine, C S

1984-05-01

Resistance to experimental autoimmune encephalomyelitis (EAE) in Hartley guinea pigs has previously been reported to be associated with disease-specific antigen-induced suppression of mitogen responses in vitro. The present studies were initiated to investigate the requirement for different cell populations in this suppression. Intact and adherent-cell-depleted cultures of spleen cells from experimental and control animals were incubated with myelin basic protein (MBP), the major antigen of EAE, with the T-cell mitogen concanavalin A (Con A) alone or with Con A in the presence of MBP. In agreement with previous studies, MBP-induced suppression of the Con A response was observed only in cultures derived from resistant animals. In addition, it was observed that this suppression was abrogated by depletion of adherent cells. When cells from resistant and susceptible animals were mixed, suppression occurred only in the presence of nonadherent cells from resistant guinea pigs. Adherent cells from either resistant or susceptible animals functioned equally well. Cultures of purified E-rosette-forming cells (E+) from resistant animals (i.e., T cells) showed no suppression. Similarly, cells from these same animals which were depleted of E+ cells (i.e., non-T cells) did not demonstrate suppression in vitro. Upon reconstitution of spleen cell populations from resistant guinea pigs by mixing E+ and E- cells, suppression was restored. These experiments show that this model of suppression in vitro requires adherent cells as well as T cells and suggests that antigen-induced suppression of mitogen responses is dependent upon a cell-mediated immunologic mechanism.

A novel co-culture model of murine K12 osteosarcoma cells and S. aureus on common orthopedic implant materials: 'the race to the surface' studied in vitro.

PubMed

McConda, David B; Karnes, Jonathan M; Hamza, Therwa; Lindsey, Brock A

2016-07-01

Infection is a major cause of orthopedic implant failure. There are few studies assessing both tissue cell and bacterial adherence on common orthopedic implant materials in a co-culture environment. An in vitro co-culture model was created using K12 osteosarcoma cells and Staphylococcus aureus in a medium incubated over metal disks for 48 h. The results showed that, in the presence of S. aureus, there were fewer osteosarcoma cells attached to the disks for all substrata tested. There were significantly more osteosarcoma cells adhering to the cobalt chrome than the stainless steel and titanium disks. Overall, in the presence of osteosarcoma cells, there were more bacteria adhering to the disks for all the substrata tested, with significantly more bacteria adhering to the stainless steel disks compared to cobalt chrome and titanium disks. Scanning electron microscopy verified that osteosarcoma cells and bacteria were adherent to the metal disks after incubation for 48 h. Furthermore, the observation that more bacteria were in the co-culture than in the control sample suggests that the osteosarcoma cells serve as a nutrient source for the bacteria. Future models assessing the interaction of osteogenic cells with bacteria on a substratum would be improved if the model accounted for the role of the immune system in secondary bone healing.

Adhesion of a monolayer of fibroblast cells to fibronectin under sonic vibrations in a bioreactor.

PubMed

Titze, Ingo R; Klemuk, Sarah A; Lu, Xiaoying

2012-06-01

We examined cell adhesion to a surface under vibrational forces approximating those of phonation. A monolayer of human fibroblast cells was seeded on a fibronectin-coated glass coverslip, which was attached to either the rotating part or the stationary part of a rheometer-bioreactor. The temperature, humidity, carbon dioxide level, nutrients, and cell seeding density were controlled. The cell density was on the order of 1,000 to 5,000 cells per square millimeter. Target stresses above 1 kPa at an oscillatory frequency of 100 Hz were chosen to reflect conditions of vocal fold tissue vibration. Fibronectin coating provided enough adhesion to support at least 2 kPa of oscillating stress, but only about 0.1 kPa of steady rotational shear. For stresses exceeding those limits, the cells were not able to adhere to the thin film of fibronectin. Cells will adhere to a planar surface under stresses typical of phonation, which provide a more stringent test than adherence in a 3-dimensional matrix. The density of cell seeding on the coverslip played a role in cell-extracellular matrix adhesion, in that the cells adhered to each other more than to the fibronectin coating when the cells were nearly confluent.

[Cytocompatibility of collagen membranes with bladder transitional cells of rabbit in vitro].

PubMed

Sun, Daodong; Song, Bo; Sun, Danning

2004-05-01

To evaluate the cytocompatibility of collagen membranes with transitional cells of rabbit in vitro and to discuss the possibility of the collagen membranes as urologic tissue engineering scaffolds. Primary cultured transitional cells isolated from New Zealand rabbits were implanted on collagen membranes at 1 x 10(5) cells/cm2. The changes of cell adhering were observed by inverted microscope and scanning electron microscope 2, 12 and 24 hours later. The experiment was divided into 4 groups: non-cell group (black control) culture medium group (negative control), extract medium from Polyvinyl chloride group(positive control) and extract medium from collagen membranes group(experimental group). The cells of generations 2 to 4 were implanted in 96-hole-plank at 1 x 10(4) cells every hole. And every group had 5 holes. Then absorption coefficient were detected at the wave length of 490 nm by MTT assay. Then the cytotoxicity and cytocompatibility were evaluated by comparison of the numbers of absorption coefficient. The bladder transitional cells began to adhere to the collagen membrane 2 hours after implanting, and the number of the adhered cells increased with time. The actual absorption coefficient of experimental groups was 0.590 +/- 0.024, 1.065 +/- 0.40 and 1.129 +/- 0.074 after 24, 72 and 120 hours. The actual absorption coefficient of negative control group was 0.639 +/- 0.068, 1.022 +/- 0.044 and 1.087 +/- 0.111. The actual absorption coefficient of positive control group was 0.302 +/- 0.029, 0.653 +/- 0.083 and 0.694 +/- 0.031. There was significant difference between the experimental group and positive control (P < 0.01), and no significant difference between the experimental group and negative control(P > 0.05). Collagen membrane has good cytocompatibility with transitional cells and no cytotoxicity. It can be used as scaffolds of urologic tissue engineering.

Adhesion and proliferation of fibroblasts on RF plasma-deposited nanostructured fluorocarbon coatings: evidence of FAK activation.

PubMed

Rosso, Francesco; Marino, Gerardo; Muscariello, Livio; Cafiero, Gennaro; Favia, Pietro; D'Aloia, Erica; d'Agostino, Riccardo; Barbarisi, Alfonso

2006-06-01

We used combined plasma-deposition process to deposit smooth and nanostructured fluorocarbon coatings on polyethylenethereftalate (PET) substrates, to obtain surfaces with identical chemical composition and different roughness, and investigate the effect of surface nanostructures on adhesion and proliferation of 3T3 Swiss Albino Mouse fibroblasts. Untreated PET and polystyrene (PS) were used as controls for cell culture. We have found that the statistically significant increase of cell proliferation rate and FAK (a nonreceptor tyrosine kinase) activation detected on ROUGH fluorocarbon surfaces is due to the presence of nanostructures. Changes in cytoskeletal organization and phospho FAK (tyr 397) localization were evident after 60 min on cells adhering to ROUGH surfaces. This change was characterized by the formation of actin stress fibers along lamellar membrane protrusion instead of usual focal contacts. Also the morphology of the adhering fibroblasts (60 min) adhering on ROUGH surfaces was found quite different compared to cells adhering on smooth ones. Copyright 2006 Wiley-Liss, Inc.

Voltage controlled nano-injection system for single-cell surgery

PubMed Central

Seger, R. Adam; Actis, Paolo; Penfold, Catherine; Maalouf, Michelle; Vilozny, Boaz; Pourmand, Nader

2015-01-01

Manipulation and analysis of single cells is the next frontier in understanding processes that control the function and fate of cells. Herein we describe a single-cell injection platform based on nanopipettes. The system uses scanning microscopy techniques to detect cell surfaces, and voltage pulses to deliver molecules into individual cells. As a proof of concept, we injected adherent mammalian cells with fluorescent dyes. PMID:22899383

Voltage controlled nano-injection system for single-cell surgery.

PubMed

Adam Seger, R; Actis, Paolo; Penfold, Catherine; Maalouf, Michelle; Vilozny, Boaz; Pourmand, Nader

2012-09-28

Manipulation and analysis of single cells is the next frontier in understanding processes that control the function and fate of cells. Herein we describe a single-cell injection platform based on nanopipettes. The system uses scanning microscopy techniques to detect cell surfaces, and voltage pulses to deliver molecules into individual cells. As a proof of concept, we injected adherent mammalian cells with fluorescent dyes.

Can wireless text messaging improve adherence to preventive activities? Results of a randomised controlled trial.

PubMed

Cocosila, Mihail; Archer, Norm; Haynes, R Brian; Yuan, Yufei

2009-04-01

To determine the effectiveness of cell phone wireless text messaging for improving adherence to a healthy behaviour. A randomised, unblinded, controlled trial was conducted with 102 subjects, 18 years or older, each having a cell phone and willing to take 1 vitamin C pill per day for 1 month for preventive reasons. Intervention group participants received text messaging reminders and were asked to acknowledge receiving their messages after taking the vitamins, whereas control group subjects had no text messaging activity. Self-reported adherence and the number of participant text messages acknowledging vitamins taken. Both groups reported an increased adherence after the trial: by 246% for the intervention group and by 131% for the control group. There was a non-significant difference between the two groups at endpoint: an average difference of 0.8 between the number of pills missed in the last week of the trial (2.5 out of 7 in the intervention and 3.3 out of 7 in the control group) with a power of 0.54. The study revealed a significant correlation (coefficient=-0.352, sig.=0.01) between the average number of text messaging acknowledgements sent by the intervention group participants and the number of pills they reported missed during the last week of the trial. This was a small randomised controlled trial with inconclusive but encouraging results. It suggests a new approach in addressing insufficient adherence in outpatient conditions and shows that the use of information technology tools for compliance warrants further research.

Biological evaluation of partially stabilized zirconia added HA/HDPE composites with osteoblast and fibroblast cell lines.

PubMed

Yari Sadi, Amir; Shokrgozar, Mohammad Ali; Homaeigohar, Seyed Shahin; Khavandi, Alireza

2008-06-01

In the present study, the biocompatibility of partially stabilized zirconia (PSZ) added hydroxyapatite (HA)--high density polyethylene (HDPE) composites was evaluated by proliferation and cell attachment assays on two osteoblast cell lines (G-292, Saos-2) and a type of fibroblast cell isolated from bone tissue namely HBF in different time intervals. Cell-material interactions on the surface of the composites were observed by scanning electron microscopy (SEM). The effect of composites on the behavior of osteoblast and fibroblast cells was compared with those of HDPE and Tissue Culture Poly Styrene (TPS) (as negative control) samples. Results showed that the composite samples supported a higher proliferation rate of osteoblast cells in the presence of composite samples as compared to the HDPE and TPS samples after 3, 7 and 14 days of incubation period. It was showed that an equal or in some cases an even higher proliferation rate of G-292 and Saos-2 osteoblast cells on composite samples in compare to negative controls in culture period (P < 0.05). The number of adhered cells on the composite samples was equal and in some cases higher than the number adhered on the HDPE and TPS samples after the above mentioned incubation periods (P < 0.05). Adhered cells presented a normal morphology by SEM and many of the cells were seen to be undergoing cell division.

In vitro antibacterial activity of adhesive systems on Streptococcus mutans.

PubMed

Paradella, Thaís Cachuté; Koga-Ito, Cristiane Yumi; Jorge, Antonio Olavo Cardoso

2009-04-01

To evaluate the antibacterial activity of three adhesive systems -- Prime & Bond 2.1 (PB), Clearfil SE Bond (CS) and One Up Bond F (OU) -- on Streptococcus mutans in vitro. Adherence and agar disk-diffusion tests were performed. For the adherence testing, 40 human enamel specimens (4 mm2) were sterilized and the adhesive sytems were applied (n = 10). The control group did not receive the application of any adhesive system. Specimens were immersed in brain heart infusion broth (BHI) inoculated with S. mutans standardized suspension (10(6) cells/ml) for 48 h at 37 degrees C and 5% CO2. The number of S. mutans cells adhered to each specimen was evaluated by the plating method on BHI agar. For agar disk-diffusion testing, adhesive disks and disks soaked in distilled water (negative control) or 0.2% chlorexidine (positive control) were incubated with S. mutans for 48 h. The diameters of the zones of bacterial inhibition were measured. Adherence data were transformed in logarithms of base 10 (log10). Data were submitted to Kruskal-Wallis and Student-Neuman-Keuls tests at the 5% level of significance. The results of the adherence test showed that One Up Bond F (OU) and Clearfil SE Bond (CS) did not differ significantly from one another, but allowed significantly less adherence than Prime & Bond 2.1 (PB) and control [mean log10 (standard deviation) values: PB 6.10 (0.19); CS primer 4.55 (0.98); OU 4.65 (0.54); control group 6.34 (0.27)]. The disk-diffusion test showed no significant difference between OU (diameter in mm: 3.02 +/- 0.13) and CS (3.0 +/- 0.12), but both were significantly more effective in inhibiting bacterial growth than PB (1.0 +/- 0.10). The self-etching systems Clearfil SE Bond and One Up Bond F presented a greater inhibitory effect against S. mutans, also in terms of adherence, than did the conventional system, Prime & Bond 2.1.

Enrichment of skin-derived neural precursor cells from dermal cell populations by altering culture conditions.

PubMed

Bayati, Vahid; Gazor, Rohoullah; Nejatbakhsh, Reza; Negad Dehbashi, Fereshteh

2016-01-01

As stem cells play a critical role in tissue repair, their manipulation for being applied in regenerative medicine is of great importance. Skin-derived precursors (SKPs) may be good candidates for use in cell-based therapy as the only neural stem cells which can be isolated from an accessible tissue, skin. Herein, we presented a simple protocol to enrich neural SKPs by monolayer adherent cultivation to prove the efficacy of this method. To enrich neural SKPs from dermal cell populations, we have found that a monolayer adherent cultivation helps to increase the numbers of neural precursor cells. Indeed, we have cultured dermal cells as monolayer under serum-supplemented (control) and serum-supplemented culture, followed by serum free cultivation (test) and compared. Finally, protein markers of SKPs were assessed and compared in both experimental groups and differentiation potential was evaluated in enriched culture. The cells of enriched culture concurrently expressed fibronectin, vimentin and nestin, an intermediate filament protein expressed in neural and skeletal muscle precursors as compared to control culture. In addition, they possessed a multipotential capacity to differentiate into neurogenic, glial, adipogenic, osteogenic and skeletal myogenic cell lineages. It was concluded that serum-free adherent culture reinforced by growth factors have been shown to be effective on proliferation of skin-derived neural precursor cells (skin-NPCs) and drive their selective and rapid expansion.

Randomized controlled trial of a mobile phone intervention for improving adherence to naltrexone for alcohol use disorders.

PubMed

Stoner, Susan A; Arenella, Pamela B; Hendershot, Christian S

2015-01-01

Naltrexone is a front-line treatment for alcohol use disorders, but its efficacy is limited by poor medication adherence. This randomized controlled trial evaluated whether a mobile health intervention could improve naltrexone adherence. Treatment-seeking participants with an alcohol use disorder (N = 76) were randomized to intervention and control conditions. All participants received naltrexone (50 mg/day) with a medication event monitoring system (MEMS) and a prepaid smartphone, and received a daily text message querying medication side effects, alcohol use, and craving. Those in the intervention arm received additional medication reminders and adherence assessment via text message. The primary outcome, proportion of participants with adequate adherence (defined as ≥80% of prescribed doses taken through Week 8), did not differ between groups in intent-to-treat analyses (p = .34). Mean adherence at study midpoint (Week 4) was 83% in the intervention condition and 77% in the control condition (p = .35). Survival analysis found that the intervention group sustained adequate adherence significantly longer (M = 19 days [95% CI = 0.0-44.0]) than those in the control group (M = 3 days [95% CI = 0.0-8.1]) during the first month of treatment (p = .04). Medication adherence did not predict drinking outcomes. These results suggest that in the context of daily monitoring and assessment via cell phone, additional text message reminders do not further improve medication adherence. Although this initial trial does not provide support for the efficacy of text messaging to improve adherence to pharmacotherapy for alcohol use disorders, additional trials with larger samples and alternate designs are warranted. ClinicalTrials.gov: NCT01349985.

Optimization of proximity ligation assay (PLA) for detection of protein interactions and fusion proteins in non-adherent cells: application to pre-B lymphocytes.

PubMed

Debaize, Lydie; Jakobczyk, Hélène; Rio, Anne-Gaëlle; Gandemer, Virginie; Troadec, Marie-Bérengère

2017-01-01

Genetic abnormalities, including chromosomal translocations, are described for many hematological malignancies. From the clinical perspective, detection of chromosomal abnormalities is relevant not only for diagnostic and treatment purposes but also for prognostic risk assessment. From the translational research perspective, the identification of fusion proteins and protein interactions has allowed crucial breakthroughs in understanding the pathogenesis of malignancies and consequently major achievements in targeted therapy. We describe the optimization of the Proximity Ligation Assay (PLA) to ascertain the presence of fusion proteins, and protein interactions in non-adherent pre-B cells. PLA is an innovative method of protein-protein colocalization detection by molecular biology that combines the advantages of microscopy with the advantages of molecular biology precision, enabling detection of protein proximity theoretically ranging from 0 to 40 nm. We propose an optimized PLA procedure. We overcome the issue of maintaining non-adherent hematological cells by traditional cytocentrifugation and optimized buffers, by changing incubation times, and modifying washing steps. Further, we provide convincing negative and positive controls, and demonstrate that optimized PLA procedure is sensitive to total protein level. The optimized PLA procedure allows the detection of fusion proteins and protein interactions on non-adherent cells. The optimized PLA procedure described here can be readily applied to various non-adherent hematological cells, from cell lines to patients' cells. The optimized PLA protocol enables detection of fusion proteins and their subcellular expression, and protein interactions in non-adherent cells. Therefore, the optimized PLA protocol provides a new tool that can be adopted in a wide range of applications in the biological field.

Evaluation of biocompatibility of sodium perborate and 30% hydrogen peroxide using the analysis of the adherence capacity and morphology of macrophages.

PubMed

Asfora, Kattyenne Kabbaz; Santos, Maria do Carmo Moreira da Silva; Montes, Marcos Antonio Japiassú Resende; de Castro, Célia Maria Machado Barbosa

2005-02-01

The purpose of this study was to evaluate the biocompatibility of the most used bleaching materials for pulpless teeth, sodium perborate and 30% hydrogen peroxide, in an experimental model of macrophages, through analysis of the adherence index and the cellular morphology. Inflammatory macrophages were obtained from peritoneal washed of Wistar rats. The evaluation of the adherence capacity of these cells to the plastic surface was conducted in Eppendorf tubes containing RPMI, after treatment with the bleaching agents diluted in 1:10, 1:100 and 1:1000 for 15 and 30 min, and incubation at 37 degrees C and humidified atmosphere of 5% CO(2) in air. The cellular morphology was verified after incubation of the cells treated with the bleaching agents in culture plaques and compared with normal cells in culture medium. Results showed that sodium perborate neither increased the adherence index, nor altered the cellular morphology when compared to the control group. The distribution, cellular morphology, cytoplasmatic and nuclear characteristics, reproduced the aspects observed in normal macrophages. However, the treatment with 30% hydrogen peroxide presented an increase in adherence index when compared to the control group (RPMI), in all dilutions, according to Mann-Whitney test (n=08 and p=0.001 for dilutions 1:10 and 1:100, and n=08 and p=0.004 for dilution 1:1000). The morphology of the cells treated with this product presented structural alterations proportionally greater, depending on the dilution of this bleaching agent, and even in the highest dilution (1:1000) the cells presented very evident alterations. This irreversible cellular damage as well as the elevation of the adherence index, characterizes the aggressive potential of 30% hydrogen peroxide, regardless of its dilution. Sodium perborate, on the other hand, showed biocompatibitity, since, no morphological nor functional alteration was observed in macrophages.

Exercise Intervention: Attrition, Compliance, Adherence, and Progression Following Hematopoietic Stem Cell Transplantation
.

PubMed

Peters, Tara; Erdmann, Ruby; Hacker, Eileen Danaher

2018-02-01

Exercise is widely touted as an effective intervention to optimize health and well-being after high-dose chemotherapy and hematopoietic stem cell transplantation. 
. This article reports attrition, compliance, adherence, and progression from the strength training arm of the single-blind randomized, controlled trial Strength Training to Enhance Early Recovery (STEER). 
. 37 patients were randomized to the intervention and participated in a structured strength training program introduced during hospitalization and continued for six weeks after release. Research staff and patients maintained exercise logs to document compliance, adherence, and progression. 
. No patients left the study because of burden. Patients were compliant with completion of exercise sessions, and their adherence was high; they also progressed on their exercise prescription. Because STEER balances intervention effectiveness with patient burden, the findings support the likelihood of successful translation into clinical practice.

Relationship of Ehrlichia canis-Infected Mononuclear Cells to Blood Vessels of Lungs 1

PubMed Central

Simpson, Charles F.

1974-01-01

The lung tissue of six dogs with ehrlichiosis and two control dogs was examined with the electron microscope. Mononuclear cells containing inclusions (morulae) of Ehrlichia canis were adhered at one or more sites to the luminal surfaces of endothelial cells of arterioles or capillaries by way of interdigitations or areas of adherence, or an endothelial cell-bound mononuclear cell was chained to another parasitized or nonparasitized mononuclear cell in the lumen. The bifurcation of arterioles was the most common site at which mononuclear cells clung to the endothelium. Cell-free bodies (morulae), enclosed by a single membrane, were present in the lumens of arterioles. Such cell-free bodies were swollen and vesiculated as compared with intracytoplasmic inclusions (morulae) in mononuclear cells. Images PMID:4372174

Isolation and functional characteristics of adherent phagocytic cells from mouse Peyer's patches.

PubMed Central

MacDonald, T T; Carter, P B

1982-01-01

Attempts were made to isolate adherent phagocytic cells (macrophages) from mouse Peyer's patch cell suspensions. Cell suspensions prepared by teasing apart the Peyer's patches contained no adherent phagocytic cells. However, if Peyer's patch fragments were treated with collagenase to disrupt the tissue matrix, cells prepared in this way contained a subpopulation of adherent phagocytic cells. These cells comprised only 0.1-0.2% of the total nucleated cell population of the Peyer's patch. Similar cells could also be isolated from the Peyer's patches of germ-free mice, but as judged by their ability to ingest opsonized erythrocytes, these cells were less activated than cells from the Peyer's patches of normal mice. Adherent cells from the Peyer's patches of normal mice could present antigen (ovalbumin) to T cells, and Peyer's patches cell suspensions containing adherent cells could be stimulated in vitro to produce an anti-sheep red blood cell plaque-forming cell response in the absence of 2-mercaptoethanol. These studies show that although the frequency of phagocytic adherent cells is extremely low in Peyer's patches, these cells have functions consistent with that of adherent cells in other lymphoid tissues. PMID:7068173

Risk factors for Kaposi's sarcoma in human immunodeficiency virus patients after initiation of antiretroviral therapy: A nested case-control study in Kenya.

PubMed

Lupia, Rodgers; Wabuyia, Peter B; Otiato, Peter; Fang, Chi-Tai; Tsai, Feng-Jen

2017-12-01

This study aimed to evaluate the association between highly active antiretroviral therapy (HAART) adherence and development of Kaposi's sarcoma (KS) in human immunodeficiency virus (HIV)/AIDS patients. We conducted a retrospective nested case-control study of 165 participants (33 cases and 132 controls) receiving HAART care at Maseno Hospital, Kenya, from January 2005 to October 2013. Cases were HIV-positive adults with KS, who were matched with controls in a ratio of 1:4 based on age (±5 years of each case), sex, and KS diagnosis date. Perfect adherence to HAART was assessed on every clinic visit by patients' self-reporting and pill counts. Chi-square tests were performed to compare socioeconomic and clinical statuses between cases and controls. A conditional logistic regression was used to assess the effects of perfect adherence to HAART, the latest CD4 count, education level, distance to health-care facility, initial World Health Organization stage, and number of regular sexual partners on the development of KS. Only 63.6% participants reported perfect adherence, and the control group had a significantly higher percentage of perfect adherence (75.0%) than did cases (18.2%). After adjustment for potential imbalances in the baseline and clinical characteristics, patients with imperfect HAART adherence had 20-times greater risk of developing KS than patients with perfect HAART adherence [hazard ratios: 21.0, 95% confidence interval: 4.2-105.1]. Patients with low latest CD4 count (≤350 cells/mm 3 ) had a seven-times greater risk of developing KS than did their counterparts (HRs: 7.1, 95% CI: 1.4-36.2). Imperfect HAART adherence and low latest CD4 count are significantly associated with KS development. Copyright © 2015. Published by Elsevier B.V.

Adherence of Moraxella bovis to cell cultures of bovine origin.

PubMed

Annuar, B O; Wilcox, G E

1985-09-01

The adherence of five strains of Moraxella bovis to cell cultures was investigated. M bovis adhered to cultures of bovine corneal epithelial and Madin-Darby bovine kidney cells but not to cell types of non-bovine origin. Both piliated and unpiliated strains adhered but piliated strains adhered to a greater extent than unpiliated strains. Antiserum against pili of one strain inhibited adherence of piliated strains but caused only slight inhibition of adherence to the unpiliated strains. Treatment of bacteria with magnesium chloride caused detachment of pili from the bacterial cell and markedly inhibited adherence of piliated strains but caused only slight inhibition of adherence by the unpiliated strains. The results suggested that adhesion of piliated strains to cell cultures was mediated via pili but that adhesins other than pili may be involved in the attachment of unpiliated strains of M bovis to cells.

Individualised motivational counselling to enhance adherence to antiretroviral therapy is not superior to didactic counselling in South African patients: findings of the CAPRISA 058 randomised controlled trial.

PubMed

van Loggerenberg, Francois; Grant, Alison D; Naidoo, Kogieleum; Murrman, Marita; Gengiah, Santhanalakshmi; Gengiah, Tanuja N; Fielding, Katherine; Abdool Karim, Salim S

2015-01-01

Concerns that standard didactic adherence counselling may be inadequate to maximise antiretroviral therapy (ART) adherence led us to evaluate more intensive individualised motivational adherence counselling. We randomised 297 HIV-positive ART-naïve patients in Durban, South Africa, to receive either didactic counselling, prior to ART initiation (n = 150), or an intensive motivational adherence intervention after initiating ART (n = 147). Study arms were similar for age (mean 35.8 years), sex (43.1 % male), CD4+ cell count (median 121.5 cells/μl) and viral load (median 119,000 copies/ml). Virologic suppression at 9 months was achieved in 89.8 % of didactic and 87.9 % of motivational counselling participants (risk ratio [RR] 0.98, 95 % confidence interval [CI] 0.90-1.07, p = 0.62). 82.9 % of didactic and 79.5 % of motivational counselling participants achieved >95 % adherence by pill count at 6 months (RR 0.96, 95 % CI 0.85-1.09, p = 0.51). Participants receiving intensive motivational counselling did not achieve higher treatment adherence or virological suppression than those receiving routinely provided didactic adherence counselling. These data are reassuring that less resource intensive didactic counselling was adequate for excellent treatment outcomes in this setting.

Individualised motivational counselling to enhance adherence to antiretroviral therapy is not superior to didactic counselling in South African patients: Findings of the CAPRISA 058 randomised controlled trial

PubMed Central

van Loggerenberg, Francois; Grant, Alison D.; Naidoo, Kogieleum; Murrman, Marita; Gengiah, Santhanalakshmi; Gengiah, Tanuja N.; Fielding, Katherine; Karim, Salim S. Abdool

2014-01-01

Concerns that standard didactic adherence counselling may be inadequate to maximise antiretroviral therapy (ART) adherence led us to evaluate more intensive individualised motivational adherence counselling. We randomised 297 HIV-positive ART-naïve patients in Durban, South Africa, to receive either didactic counselling, prior to ART initiation (n=150), or an intensive motivational adherence intervention after initiating ART (n=147). Study arms were similar for age (mean 35.8 years), sex (43.1% male), CD4+ cell count (median 121.5 cells/μl) and viral load (median 119 000 copies/ml). Virologic suppression at nine months was achieved in 89.8% of didactic and 87.9% of motivational counselling participants (risk ratio [RR] 0.98, 95% confidence interval [CI] 0.90-1.07, p=0.62). 82.9% of didactic and 79.5% of motivational counselling participants achieved >95% adherence by pill count at six months (RR 0.96, 95%CI 0.85-1.09, p=0.51). Participants receiving intensive motivational counselling did not achieve higher treatment adherence or virological suppression than those receiving routinely provided didactic adherence counselling. These data are reassuring that less resource intensive didactic counselling was adequate for excellent treatment outcomes in this setting. PMID:24696226

Effect of respiratory syncytial virus (RSV) infection on the adherence of pathogenic bacteria to human epithelial cells

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

Faden, H.; Hong, J.J.; Ogra, P.L.

1986-03-01

The effect of RSV infection on the adherence of Streptococcus pneumoniae (SP), Haemophilus influenzae (HI) and Staphylococcus aureus (SA) to human epithelial cells was determined. RSV-infected Hep-2 cell cultures at different stages of expression of surface viral antigens and bacteria labeled with /sup 3/H-thymidine were employed to examine the kinetics of bacterial adherence to virus-infected cells. RSV infection did not alter the magnitude of adherence of HI or SA to HEp-2 cells. However, adherence of SP to HEp-2 cells was significantly (P < 0.01) enhanced by prior RSV infection. The degree of adherence was directly related to the amount ofmore » viral antigen expressed on the cell surface. The adherence was temperature dependent, with maximal adherence observed at 37/sup 0/C. Heat-inactivation of SP did not alter adherence characteristics. These data suggest that RSV infection increases adherence of SP to the surface of epithelial cells in vitro. Since attachment of bacteria to mucosal surfaces is the first step in many infections, it is suggested that viral infections of epithelial cells render them more susceptible to bacterial adherence. Thus, RSV infection in vivo may predispose children to SP infections, such as in otitis media, by increasing colonization with SP.« less

Flagellar Cap Protein FliD Mediates Adherence of Atypical Enteropathogenic Escherichia coli to Enterocyte Microvilli

PubMed Central

Sampaio, Suely C. F.; Luiz, Wilson B.; Vieira, Mônica A. M.; Ferreira, Rita C. C.; Garcia, Bruna G.; Sinigaglia-Coimbra, Rita; Sampaio, Jorge L. M.; Ferreira, Luís C. S.

2016-01-01

The expression of flagella correlates with different aspects of bacterial pathogenicity, ranging from adherence to host cells to activation of inflammatory responses by the innate immune system. In the present study, we investigated the role of flagella in the adherence of an atypical enteropathogenic Escherichia coli (aEPEC) strain (serotype O51:H40) to human enterocytes. Accordingly, isogenic mutants deficient in flagellin (FliC), the flagellar structural subunit; the flagellar cap protein (FliD); or the MotAB proteins, involved in the control of flagellar motion, were generated and tested for binding to differentiated Caco-2 cells. Binding of the aEPEC strain to enterocytes was significantly impaired in strains with the fliC and fliD genes deleted, both of which could not form flagella on the bacterial surface. A nonmotile but flagellated MotAB mutant also showed impaired adhesion to Caco-2 cells. In accordance with these observations, adhesion of aEPEC strain 1711-4 to Caco-2 cells was drastically reduced after the treatment of Caco-2 cells with purified FliD. In addition, incubation of aEPEC bacteria with specific anti-FliD serum impaired binding to Caco-2 cells. Finally, incubation of Caco-2 cells with purified FliD, followed by immunolabeling, showed that the protein was specifically bound to the microvillus tips of differentiated Caco-2 cells. The aEPEC FliD or anti-FliD serum also reduced the adherence of prototype typical enteropathogenic, enterohemorrhagic, and enterotoxigenic E. coli strains to Caco-2 cells. In conclusion, our findings further strengthened the role of flagella in the adherence of aEPEC to human enterocytes and disclosed the relevant structural and functional involvement of FliD in the adhesion process. PMID:26831466

Motivational Interviewing and Cognitive-Behavioral Intervention to Improve HIV Medication Adherence Among Hazardous Drinkers

PubMed Central

Parsons, Jeffrey T.; Golub, Sarit A.; Rosof, Elana; Holder, Catherine

2009-01-01

Objective To assess the efficacy of a behavioral intervention designed to improve HIV medication adherence and reduce alcohol consumption among HIV-positive men and women. Design A randomized controlled trial conducted between July 2002 and August 2005. Setting A behavioral research center in New York City. Participants HIV-positive men and women (n = 143) who were on HIV antiretroviral medication and met criteria for hazardous drinking. Intervention Participants were randomly assigned to an 8-session intervention based on motivational interviewing and cognitive-behavioral skills building or a time- and content-equivalent educational condition. Outcome Measures Viral load, CD4 cell count, and self-reported adherence and drinking behavior were assessed at baseline and at 3- and 6-month follow-ups. Results Relative to the education condition, participants in the intervention demonstrated significant decreases in viral load and increases in CD4 cell count at the 3-month follow-up and significantly greater improvement in percent dose adherence and percent day adherence. There were no significant intervention effects for alcohol use, however, and effects on viral load, CD4 cell count, and adherence were not sustained at 6 months. Conclusions An 8-session behavioral intervention can result in improvement in self-report and biologic markers of treatment adherence and disease progression. This type of intervention should be considered for dissemination and integration into HIV clinics providing comprehensive care for HIV-positive persons with alcohol problems. Although the effect was attenuated over time, future studies might test the added effectiveness of booster sessions or ongoing adherence counseling. PMID:18077833

Single cell adhesion assay using computer controlled micropipette.

PubMed

Salánki, Rita; Hős, Csaba; Orgovan, Norbert; Péter, Beatrix; Sándor, Noémi; Bajtay, Zsuzsa; Erdei, Anna; Horvath, Robert; Szabó, Bálint

2014-01-01

Cell adhesion is a fundamental phenomenon vital for all multicellular organisms. Recognition of and adhesion to specific macromolecules is a crucial task of leukocytes to initiate the immune response. To gain statistically reliable information of cell adhesion, large numbers of cells should be measured. However, direct measurement of the adhesion force of single cells is still challenging and today's techniques typically have an extremely low throughput (5-10 cells per day). Here, we introduce a computer controlled micropipette mounted onto a normal inverted microscope for probing single cell interactions with specific macromolecules. We calculated the estimated hydrodynamic lifting force acting on target cells by the numerical simulation of the flow at the micropipette tip. The adhesion force of surface attached cells could be accurately probed by repeating the pick-up process with increasing vacuum applied in the pipette positioned above the cell under investigation. Using the introduced methodology hundreds of cells adhered to specific macromolecules were measured one by one in a relatively short period of time (∼30 min). We blocked nonspecific cell adhesion by the protein non-adhesive PLL-g-PEG polymer. We found that human primary monocytes are less adherent to fibrinogen than their in vitro differentiated descendants: macrophages and dendritic cells, the latter producing the highest average adhesion force. Validation of the here introduced method was achieved by the hydrostatic step-pressure micropipette manipulation technique. Additionally the result was reinforced in standard microfluidic shear stress channels. Nevertheless, automated micropipette gave higher sensitivity and less side-effect than the shear stress channel. Using our technique, the probed single cells can be easily picked up and further investigated by other techniques; a definite advantage of the computer controlled micropipette. Our experiments revealed the existence of a sub-population of strongly fibrinogen adherent cells appearing in macrophages and highly represented in dendritic cells, but not observed in monocytes.

Single Cell Adhesion Assay Using Computer Controlled Micropipette

PubMed Central

Salánki, Rita; Hős, Csaba; Orgovan, Norbert; Péter, Beatrix; Sándor, Noémi; Bajtay, Zsuzsa; Erdei, Anna; Horvath, Robert; Szabó, Bálint

2014-01-01

Cell adhesion is a fundamental phenomenon vital for all multicellular organisms. Recognition of and adhesion to specific macromolecules is a crucial task of leukocytes to initiate the immune response. To gain statistically reliable information of cell adhesion, large numbers of cells should be measured. However, direct measurement of the adhesion force of single cells is still challenging and today’s techniques typically have an extremely low throughput (5–10 cells per day). Here, we introduce a computer controlled micropipette mounted onto a normal inverted microscope for probing single cell interactions with specific macromolecules. We calculated the estimated hydrodynamic lifting force acting on target cells by the numerical simulation of the flow at the micropipette tip. The adhesion force of surface attached cells could be accurately probed by repeating the pick-up process with increasing vacuum applied in the pipette positioned above the cell under investigation. Using the introduced methodology hundreds of cells adhered to specific macromolecules were measured one by one in a relatively short period of time (∼30 min). We blocked nonspecific cell adhesion by the protein non-adhesive PLL-g-PEG polymer. We found that human primary monocytes are less adherent to fibrinogen than their in vitro differentiated descendants: macrophages and dendritic cells, the latter producing the highest average adhesion force. Validation of the here introduced method was achieved by the hydrostatic step-pressure micropipette manipulation technique. Additionally the result was reinforced in standard microfluidic shear stress channels. Nevertheless, automated micropipette gave higher sensitivity and less side-effect than the shear stress channel. Using our technique, the probed single cells can be easily picked up and further investigated by other techniques; a definite advantage of the computer controlled micropipette. Our experiments revealed the existence of a sub-population of strongly fibrinogen adherent cells appearing in macrophages and highly represented in dendritic cells, but not observed in monocytes. PMID:25343359

Role of the eosinophil in serum-mediated adherence of equine leukocytes to infective larvae of Strongylus vulgaris.

PubMed

Klei, T R; Chapman, M R; Dennis, V A

1992-06-01

The adherence of equine leukocytes to Strongylus vulgaris infective larvae (L3) in the presence of normal and immune sera was examined in vitro. Immune sera promoted adherence of buffy coat cells from ponies with S. vulgaris-induced eosinophilia (eosinophilic ponies) to S. vulgaris L3. However, eosinophils in the buffy coat cells were the predominant adherent cell type. Studies using leukocyte populations enriched for eosinophils, neutrophils, and mononuclear cells from eosinophilic ponies support the observations using buffy coat cells that eosinophils were the main effector cells. Adherent eosinophils from eosinophilic ponies immobilized L3. Neutrophils were less adherent and did not immobilize L3. Mononuclear cells failed to adhere. Normal eosinophils from strongly-naive ponies did not immobilize S. vulgaris L3 in the presence of immune serum, suggesting the in vivo activation of eosinophils in eosinophilic animals. Immune serum promoted less adherence of buffy coat cells to Strongylus edentatus or mixed species of Cyathostominae L3, suggesting that the serum-mediated cellular adherence phenomenon was species-specific. Normal serum promoted less cellular adherence to S. vulgaris L3 than immune serum. The adherence mediated by normal serum was removed by heat inactivation, suggesting that this nonspecific phenomenon was a complement-mediated reaction. Immune globulins promoted reactions similar to that seen using heat-inactivated immune serum, whereas normal globulins did not promote adherence. Immune globulins absorbed with pieces of S. vulgaris adult worms did not promote the adherence of buffy coat cells to S. vulgaris L3, suggesting that adult and L3 stages share antigens important in this phenomenon that resulted in the removal of specific adherence antibody during absorption.

Storage duration and white blood cell content of red blood cell (RBC) products increases adhesion of stored RBCs to endothelium under flow conditions.

PubMed

Anniss, Angela M; Sparrow, Rosemary L

2006-09-01

Adherence of red blood cells (RBCs) to vascular endothelium impairs blood flow and decreases oxygen delivery. Although RBCs may be stored for up to 42 days before transfusion under current blood banking guidelines, little is known of how changes to RBCs during storage may affect their adherence properties. The influence of RBC product storage time and white blood cell (WBC) burden on the adherence of RBCs for transfusion to vascular endothelium under conditions of continuous flow was investigated in this study. RBC samples were collected from nonleukoreduced (S-RBC), buffy coat-poor (BCP-RBC), and leukofiltered (LF-RBC) products at fixed time points during storage. Samples were perfused, at controlled shear stress and temperature, across a confluent endothelial cell (EC) monolayer with a parallel-flow chamber mounted to an inverted microscope. RBC-EC interactions were recorded with a digital camera attached to the microscope. The number of RBCs adhering to the EC layer increased significantly with storage time in all RBC products; however, WBC reduction delayed this increase. LF-RBCs were also significantly less adherent than S-RBC or BCP-RBC products on Day 1 of storage (p < 0.05). The strength of RBC attachment to vascular endothelium was significantly stronger in S-RBC products compared to BCP-RBC and LF-RBC products. Our findings indicate that product storage time and WBC burden increase the number and strength of adhesion of RBCs to vascular endothelium. These results may lead to greater understanding of the interaction of transfused RBCs with recipient endothelium and the biologic consequences of this adherence.

Evaluation of the Effects of SDIA, a LUXR Homologue, on Adherence and Motility of Escherichia coli O157:H7

USDA-ARS?s Scientific Manuscript database

Quorum-sensing (QS) signaling pathways are important regulatory networks for controlling the expression of genes promoting adherence of Enterohemorrhagic Escherichia coli (EHEC) O157:H7 to epithelial cells. A recent study has shown that EHEC O157:H7 encodes a luxR homologue, called sdiA¸ which upon...

Differential Effects of Tissue Culture Coating Substrates on Prostate Cancer Cell Adherence, Morphology and Behavior

PubMed Central

Liberio, Michelle S.; Sadowski, Martin C.; Soekmadji, Carolina; Davis, Rohan A.; Nelson, Colleen C.

2014-01-01

Weak cell-surface adhesion of cell lines to tissue culture surfaces is a common problem and presents technical limitations to the design of experiments. To overcome this problem, various surface coating protocols have been developed. However, a comparative and precise real-time measurement of their impact on cell behavior has not been conducted. The prostate cancer cell line LNCaP, derived from a patient lymph node metastasis, is a commonly used model system in prostate cancer research. However, the cells’ characteristically weak attachment to the surface of tissue culture vessels and cover slips has impeded their manipulation and analysis and use in high throughput screening. To improve the adherence of LNCaP cells to the culture surface, we compared different coating reagents (poly-l-lysine, poly-l-ornithine, collagen type IV, fibronectin, and laminin) and culturing conditions and analyzed their impact on cell proliferation, adhesion, morphology, mobility and gene expression using real-time technologies. The results showed that fibronectin, poly-l-lysine and poly-l-ornithine improved LNCaP cells adherence and provoked cell morphology alterations, such as increase of nuclear and cellular area. These coating reagents also induced a higher expression of F-actin and reduced cell mobility. In contrast, laminin and collagen type IV did not improve adherence but promoted cell aggregation and affected cell morphology. Cells cultured in the presence of laminin displayed higher mobility than control cells. All the coating conditions significantly affected cell viability; however, they did not affect the expression of androgen receptor-regulated genes. Our comparative findings provide important insight for the selection of the ideal coating reagent and culture conditions for the cancer cell lines with respect to their effect on proliferation rate, attachment, morphology, migration, transcriptional response and cellular cytoskeleton arrangement. PMID:25375165

Micromechanical Devices for Control of Cell-Cell Interaction, and Methods of Use Thereof

NASA Technical Reports Server (NTRS)

Bhatia, Sangeeta N. (Inventor); Hui, Elliot (Inventor)

2017-01-01

The development and function of living tissues depends largely on interactions between cells that can vary in both time and space; however, temporal control of cell-cell interaction is experimentally challenging. By employing a micromachined silicon substrate with moving parts, herein is disclosed the dynamic regulation of cell-cell interactions via direct manipulation of adherent cells with micron-scale precision. The inventive devices and methods allow mechanical control of both tissue composition and spatial organization. The inventive device and methods enable the investigation of dynamic cell-cell interaction in a multitude of applications, such as intercellular communication, spanning embryogenesis, homeostasis, and pathogenic processes.

RhoA-Mediated Functions in C3H10T1/2 Osteoprogenitors Are Substrate Topography Dependent.

PubMed

Ogino, Yoichiro; Liang, Ruiwei; Mendonça, Daniela B S; Mendonça, Gustavo; Nagasawa, Masako; Koyano, Kiyoshi; Cooper, Lyndon F

2016-03-01

Surface topography broadly influences cellular responses. Adherent cell activities are regulated, in part, by RhoA, a member of the Rho-family of GTPases. In this study, we evaluated the influence of surface topography on RhoA activity and associated cellular functions. The murine mesenchymal stem cell line C3H10T1/2 cells (osteoprogenitor cells) were cultured on titanium substrates with smooth topography (S), microtopography (M), and nanotopography (N) to evaluate the effect of surface topography on RhoA-mediated functions (cell spreading, adhesion, migration, and osteogenic differentiation). The influence of RhoA activity in the context of surface topography was also elucidated using RhoA pharmacologic inhibitor. Following adhesion, M and N adherent cells developed multiple projections, while S adherent cells had flattened and widespread morphology. RhoA inhibitor induced remarkable longer and thinner cytoplasmic projections on all surfaces. Cell adhesion and osteogenic differentiation was topography dependent with S < M and N surfaces. RhoA inhibition increased adhesion on S and M surfaces, but not N surfaces. Cell migration in a wound healing assay was greater on S versus M versus N surfaces and RhoA inhibitor increased S adherent cell migration, but not N adherent cell migration. RhoA inhibitor enhanced osteogenic differentiation in S adherent cells, but not M or N adherent cells. RhoA activity was surface topography roughness dependent (S < M, N). RhoA activity and -mediated functions are influenced by surface topography. Smooth surface adherent cells appear highly sensitive to RhoA function, while nano-scale topography adherent cell may utilize alternative cellular signaling pathway(s) to influence adherent cellular functions regardless of RhoA activity. © 2015 Wiley Periodicals, Inc.

Toxicity of extracts from disposable chopsticks, toothpicks, and paper cups on L-929 cells.

PubMed

Li, Juntao; Chen, Sifan; Li, Wenxue; Yang, Guangyu; Zhu, Wei

2015-04-01

To evaluate the toxicity of extracts from disposable chopsticks, toothpicks, and paper cups on L-929 cells. We followed national standards to prepare the extracts from disposable chopsticks, toothpicks, and paper cups used for the cell culture media, and the morphology of L-929 cells was observed with an optical microscope. The loss rate for adherent cells was evaluated with the trypan blue exclusion method, and cell proliferation was determined using the WST-1 assay. Compared with the control group, the cells cultured in media containing the extracts showed signs of apoptosis and necrosis after culturing for 4 or 7 days, and the loss rate for adherent cells was significantly increased (P < 0.05). An obvious decrease in cell viability was also observed (P < 0.05). The extracts from disposable chopsticks, toothpicks, and paper cups can affect the growth and proliferation of L-929 cells and are potentially toxic to humans.

A practical guide to microfluidic perfusion culture of adherent mammalian cells.

PubMed

Kim, Lily; Toh, Yi-Chin; Voldman, Joel; Yu, Hanry

2007-06-01

Culturing cells at microscales allows control over microenvironmental cues, such as cell-cell and cell-matrix interactions; the potential to scale experiments; the use of small culture volumes; and the ability to integrate with microsystem technologies for on-chip experimentation. Microfluidic perfusion culture in particular allows controlled delivery and removal of soluble biochemical molecules in the extracellular microenvironment, and controlled application of mechanical forces exerted via fluid flow. There are many challenges to designing and operating a robust microfluidic perfusion culture system for routine culture of adherent mammalian cells. The current literature on microfluidic perfusion culture treats microfluidic design, device fabrication, cell culture, and micro-assays independently. Here we systematically present and discuss important design considerations in the context of the entire microfluidic perfusion culture system. These design considerations include the choice of materials, culture configurations, microfluidic network fabrication and micro-assays. We also present technical issues such as sterilization; seeding cells in both 2D and 3D configurations; and operating the system under optimized mass transport and shear stress conditions, free of air-bubbles. The integrative and systematic treatment of the microfluidic system design and fabrication, cell culture, and micro-assays provides novices with an effective starting point to build and operate a robust microfludic perfusion culture system for various applications.

Influence of Malaria Infection on the Elaboration of Soluble Mediators by Adherent Mononuclear Cells

PubMed Central

Wyler, David J.; Oppenheim, Joost J.; Koontz, Louis C.

1979-01-01

Malaria results in two seemingly paradoxical perturbations of the immune response: polyclonal B-cell activation and immunosuppression. To determine what immunoregulatory role mediators secreted by adherent cells might play in these alterations, we cultured adherent cells from uninfected mice and from mice at different times during infection with Plasmodium berghei or P. yoelii. Culture supernatants obtained from these cells were tested for their ability to enhance the in vitro proliferative responses of thymocytes to suboptimal concentrations of concanavalin A or to inhibit the mitogen-stimulated proliferation of normal spleen cells. Supernatants obtained from adherent cells of mice early in infection (days 1 to 3) contained significantly elevated levels of enhancing activity which on Bio-Gel P-100 chromatography resembled lymphocyte-activating factor. Later in infection (days 4 and 5), these supernatants contained inhibitory activity. Normal adherent cells, when cocultivated in vitro with parasitized erythrocytes, ingested parasite debris and were stimulated to produce the enhancing factor. At high parasite/adherent-cell ratios, cells elaborated an inhibitory factor. These findings suggest that during malaria, adherent cells are converted from a nonspecific helper role to a nonspecific suppressor role. This modulation in function may be due to the direct interaction between adherent cells and parasitized erythrocytes. PMID:457269

Relationship of Inhaled Corticosteroid Adherence to Asthma Exacerbations in Patients with Moderate-to-Severe Asthma.

PubMed

Papi, Alberto; Ryan, Dermot; Soriano, Joan B; Chrystyn, Henry; Bjermer, Leif; Rodríguez-Roisin, Roberto; Dolovich, Myrna B; Harris, Mark; Wood, Lucy; Batsiou, Maria; Thornhill, Susannah I; Price, David B

2018-04-05

Patients with asthma and elevated blood eosinophils are at increased risk of severe exacerbations. Management of these patients should consider nonadherence to inhaled corticosteroid (ICS) therapy as a factor for increased exacerbation risk. The objective of this study was to investigate whether poor adherence to ICS therapy explains the occurrence of asthma exacerbations in patients with elevated blood eosinophil levels. This historical cohort study identified patients within the Optimum Patient Care Research Database, aged 18 years or more, at Global Initiative for Asthma step 3 or 4, with 2 or more ICS prescriptions during the year before the clinical review. Patient characteristics and adherence (based on prescription refills and patient self-report) for ICS therapy were analyzed for those with elevated (>400 cells/μL) or normal (≤400 cells/μL) blood eosinophils. We studied 7195 patients (66% female, mean age 60 years) with median eosinophil count of 200 cells/μL and found 81% to be not fully adherent to ICS therapy. A total of 1031 patients (14%) had elevated blood eosinophil counts (58% female, mean age 60 years), 83% of whom were not fully adherent to ICS. An increased proportion of adherent patients in the elevated blood eosinophil group had 2 or more exacerbations (14.0% vs 7.2%; P = .003) and uncontrolled asthma (73% vs 60.8%; P = .004) as compared with non-fully adherent patients. Approximately 1 in 7 patients had elevated eosinophils. Adherence to ICS therapy was not associated with decreased exacerbations for these patients. Additional therapy should be considered for these patients, such as biologics, which have been previously shown to improve control in severe uncontrolled eosinophilic asthma. Copyright © 2018 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Depressed Immune Responses and Accelerated Splenic Apoptosis due to Experience of Food Deprivation and Inequality but not Unstable Social Status in Balb/c Mice.

PubMed

Aghajani, Marjan; Vaez Mahdavi, Mohammad Reza; Najafabadi, Mohsen Khalili; Ghazanfari, Tooba; Moradi, Fatemeh; Golchoobian, Ravieh; Askari, Hasan; Sanadgol, Nima; Moghaddam, Ehsan Kazemi

2017-01-01

We aimed to show that the immune system is sensitive to the detrimental effects of inequality and social injustice, and splenic vulnerability to apoptosis may also increase. In order of better determination of immune responses to chronic social stress, we implemented food deprivation, food intake inequality, and unstable social status (a change of cage-mate every 3 days) for a period of 14 days in 60 male Balb/c mice. At the end of this stress period, nitric oxide (NO) production by peritoneal adherent cells and the serum concentration of corticosterone were measured. Moreover, the viability of peritoneal adherent cells and spleen lymphocytes was evaluated by MTT assay. The terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay was done to reveal the TUNEL-reactive apoptotic bodies in the spleen. Our results showed that food deprivation and inequality caused significant changes in the apoptosis of splenic cells in comparison with the control group (p < 0.05). Moreover, the vital activities of lymphocytes and peritoneal adherent cells, as well as NO production by the latter, increased significantly (p < 0.05). However, the experience of unstable social status did not cause a further increase in the viability of lymphocytes and peritoneal adherent cells, or NO production in animals that were food-deprived or experienced inequality. Serum concentration of corticosterone in all experimental groups, except for animals that experienced unstable social status only, significantly decreased versus the control group (p < 0.05). The results suggest that poverty and social inequality, but not unstable social status, affect immune responses and are likely involved in the induction of splenic apoptosis in mice. © 2017 S. Karger AG, Basel.

Adherence of Trichomonas vaginalis to cell culture monolayers.

PubMed

Martinotti, M G; Martinetto, P; Savoia, D

1986-06-01

The in vitro adherence to WISH cells of a pathogenic Trichomonas vaginalis strain was studied with a method utilizing thymidine-labeled protozoa. A marked dose-related adherence was observed. Glutaraldehyde fixed trichomonads were not adherent. The presence of fetal calf serum during the assay did not influence attachment. Concanavalin A inhibited adherence of protozoa. Complete or partial inhibition of adherence was achieved by preincubating WISH cells with Lactobacillus fermentum or Streptococcus agalactiae. Finally, pretreatment of cells with alpha-estradiol, beta-estradiol, progesterone and estrone influenced attachment of protozoa, whereas estriol was ineffective. These results suggest that adherence of Trichomonas vaginalis is dependent on different factors, whose manipulation may have clinical relevance in preventing recurrence of trichomonad vaginitis.

NCAM polysialylation during adherence transitions: live cell monitoring using an antibody-mimetic EGFP-endosialidase and the viability dye DRAQ7.

PubMed

Smith, Paul J; Furon, Emeline; Wiltshire, Marie; Chappell, Sally; Patterson, Laurence H; Shnyder, Steven D; Falconer, Robert A; Errington, Rachel J

2013-07-01

Polysialylation of neural cell adhesion molecule (NCAM) in small-cell lung cancer (SCLC) is thought to regulate NCAM-mediated cell-surface interactions, imparting antiadhesive properties to cells. However, SCLC cells in culture demonstrate anchorage-independent growth and spontaneously generate adherent forms. Here, the ability of polySia-NCAM to influence cell proliferation and adherence is unclear. We analyzed live SCLC cell polySia-NCAM expression by flow cytometry, using the novel combination of a polySia antibody-mimetic eGFP-tagged endosialidase and the viability dye DRAQ7. Enrichment for adherence (<30 population doublings) in SCLC cell lines resolved populations with increased (SHP-77 and COR-L279) or negligible (NCI-H69) polysialylation compared with nonadherent parent populations. Adherent forms retained NCAM expression as confirmed by immunofluorescence and immunoblotting. Initial transition to adherence and loss of polysialylation in NCI-H69 was linked to a reduced proliferation rate with no increase in cell death. This reduced proliferation rate was reiterated in vivo as determined by the growth of noninvasive subcutaneous xenografts in mice. Continued selection for enhanced substrate adherence in NCI-H69 (>150 population doublings) resolved cells with stable re-expression of polySia and increased growth rates both in vitro and in vivo. Endoneuraminidase removal of polySia from re-expressing cells showed that rapid adherence to extracellular matrix components was functionally independent of polySia. PolySia expression was not altered when isolated adherent forms underwent enforced cell-cell contact in three-dimensional culture. Coculture of polySia expression variants modulated overall polySia expression profiles indicating an influence of SCLC microcommunity composition independent of substrate adherence potential. We conclude that an obligatory linkage between substrate adherence potential and polySia expression is rejected for SCLC cells. We suggest that a degree of homeostasis operates to regulate polysialylation within heterogeneous cell populations. The findings suggest a new model for SCLC progression while the application of live cell profiling of polysialylation could be used to assess polySia-NCAM-targeted therapies. Copyright © 2013 International Society for Advancement of Cytometry.

Candida albicans and Pseudomonas aeruginosa adhesion on soft contact lenses.

PubMed

Onurdağ, Fatma Kaynak; Ozkan, Semiha; Ozgen, Selda; Olmuş, Hülya; Abbasoğlu, Ufuk

2011-04-01

In this study it was aimed to determine the adherence of Pseudomonas and Candida to contact lens surfaces, and to determine the difference in adherence between five contact lens types. Biofilm-negative control strains were also used to emphasize the difference between biofilm-positive and biofilm-negative strains in adherence. Five different soft contact lenses were used to investigate the adherence of Pseudomonas aeruginosa and Candida albicans strains. P. aeruginosa ATCC 27853, P. aeruginosa ATCC 10145, C.albicans ATCC 10231 standard strains and C. albicans clinical isolate were included in the study. Slime formation was investigated by two methods; modified Christensen macrotube method, and a modified microtiter plate test. P. aeruginosa and C. albicans slime formation on soft contact lenses was studied in adherence and separation phases. Pseudomonas and Candida suspensions were serially diluted and inoculated to blood agar and sabouraud dextrose agar surfaces respectively. After overnight incubation, the colonies were counted. Sterile unworn contact lenses were used as negative controls, and bacterial and fungal culture suspensions were used as positive controls. The experiments were conducted in three parallel series. The number of adherent Pseudomonas was as follows from high to low in polymacon, etafilcon A, hilafilcon, ocufilcon and lotrafilcon contact lenses respectively. However, the number of adherent yeast were determined higher in lotrafilcon and ocufilcon contact lenses, followed by hilafilcon, etafilcon A and polymacon contact lenses. Biofilm-negative Pseudomonas ATCC standard strain and Candida clinical isolate were used to confirm that the number of adherent cells were lower than the biofilm-positive ones. This study demonstrates that in addition to the contact lens properties, the microorganisms themselves and their interactions with the lens material also play an important role in adherence.

Surface Display of the Receptor-Binding Region of the Lactobacillus brevis S-Layer Protein in Lactococcus lactis Provides Nonadhesive Lactococci with the Ability To Adhere to Intestinal Epithelial Cells

PubMed Central

Åvall-Jääskeläinen, Silja; Lindholm, Agneta; Palva, Airi

2003-01-01

Lactobacillus brevis is a promising lactic acid bacterium for use as a probiotic dietary adjunct and a vaccine vector. The N-terminal region of the S-layer protein (SlpA) of L. brevis ATCC 8287 was recently shown to mediate adhesion to various human cell lines in vitro. In this study, a surface display cassette was constructed on the basis of this SlpA receptor-binding domain, a proteinase spacer, and an autolysin anchor. The cassette was expressed under control of the nisA promoter in Lactococcus lactis NZ9000. Western blot assay of lactococcal cell wall extracts with anti-SlpA antibodies confirmed that the SlpA adhesion domain of the fusion protein was expressed and located within the cell wall layer. Whole-cell enzyme-linked immunosorbent assay and immunofluorescence microscopy verified that the SlpA adhesion-mediating region was accessible on the lactococcal cell surface. In vitro adhesion assays with the human intestinal epithelial cell line Intestine 407 indicated that the recombinant lactococcal cells had gained an ability to adhere to Intestine 407 cells significantly greater than that of wild-type L. lactis NZ9000. Serum inhibition assay further confirmed that adhesion of recombinant lactococci to Intestine 407 cells was indeed mediated by the N terminus-encoding part of the slpA gene. The ability of the receptor-binding region of SlpA to adhere to fibronectin was also confirmed with this lactococcal surface display system. These results show that, with the aid of the receptor-binding region of the L. brevis SlpA protein, the ability to adhere to gut epithelial cells can indeed be transferred to another, nonadhesive, lactic acid bacterium. PMID:12676705

Surface display of the receptor-binding region of the Lactobacillus brevis S-layer protein in Lactococcus lactis provides nonadhesive lactococci with the ability to adhere to intestinal epithelial cells.

PubMed

Avall-Jääskeläinen, Silja; Lindholm, Agneta; Palva, Airi

2003-04-01

Lactobacillus brevis is a promising lactic acid bacterium for use as a probiotic dietary adjunct and a vaccine vector. The N-terminal region of the S-layer protein (SlpA) of L. brevis ATCC 8287 was recently shown to mediate adhesion to various human cell lines in vitro. In this study, a surface display cassette was constructed on the basis of this SlpA receptor-binding domain, a proteinase spacer, and an autolysin anchor. The cassette was expressed under control of the nisA promoter in Lactococcus lactis NZ9000. Western blot assay of lactococcal cell wall extracts with anti-SlpA antibodies confirmed that the SlpA adhesion domain of the fusion protein was expressed and located within the cell wall layer. Whole-cell enzyme-linked immunosorbent assay and immunofluorescence microscopy verified that the SlpA adhesion-mediating region was accessible on the lactococcal cell surface. In vitro adhesion assays with the human intestinal epithelial cell line Intestine 407 indicated that the recombinant lactococcal cells had gained an ability to adhere to Intestine 407 cells significantly greater than that of wild-type L. lactis NZ9000. Serum inhibition assay further confirmed that adhesion of recombinant lactococci to Intestine 407 cells was indeed mediated by the N terminus-encoding part of the slpA gene. The ability of the receptor-binding region of SlpA to adhere to fibronectin was also confirmed with this lactococcal surface display system. These results show that, with the aid of the receptor-binding region of the L. brevis SlpA protein, the ability to adhere to gut epithelial cells can indeed be transferred to another, nonadhesive, lactic acid bacterium.

Matrix MetalloProteinases (MMPs) andTissue Inhibitors of MetalloProteinases (TIMPs): positive and negative regulators intumor cell adhesion

PubMed Central

Bourboulia, Dimitra; Stetler-Stevenson, William G.

2010-01-01

Cells adhere to one another and/or to matrices that surround them. Regulation of cell-cell (intercellular) and cell-matrix adhesion is tightly controlled in normal cells, however, defects in cell adhesion are common in the majority of humancancers. Multilateral communication among tumor cells with the extracellular matrix (ECM) and neighbor cells is accomplished through adhesion molecules, ECM components, proteolytic enzymes and their endogenous inhibitors. There is sufficient evidence to suggest that reduced adherence is a tumor cell propertyengaged during tumor progression. Tumor cells acquire the ability to change shape, detach and easily move through spaces disorganizing the normal tissue architecture. This property is due to changes in expression levels of adhesion molecules and/or due to elevated levels of secreted proteolytic enzymes, including matrix metalloproteinases (MMPs). Among other roles, MMPsdegrade the ECMand, therefore, prepare the path for tumor cells to migrate, invade and spread to distant secondary areas, where they form metastasis. Tissue Inhibitors of Metalloproteinases or TIMPs control MMP activities and, therefore, minimize matrix degradation. Both MMPs and TIMPs are involved in tissue remodeling and decisively regulate tumor cell progression including tumor angiogenesis. In this review, we describe and discuss data that support the important role of MMPs and TIMPs in cancer cell adhesion and tumor progression. PMID:20470890

Micro- and Nano-scale Technologies for Delivery into Adherent Cells

PubMed Central

Kang, Wonmo; McNaughton, Rebecca L.; Espinosa, Horacio D.

2016-01-01

Several recent micro- and nano-technologies have provided novel methods for biological studies of adherent cells because the small features of these new biotools provide unique capabilities for accessing cells without the need for suspension or lysis. These novel approaches have enabled gentle, yet effective delivery of molecules into specific adhered target cells, with unprecedented spatial resolution. Here we review recent progress in the development of these technologies with an emphasis on in vitro delivery into adherent cells utilizing mechanical penetration or electroporation. We discuss major advantages and limitations of these approaches and propose possible strategies for improvements. Finally, we discuss the impact of these technologies on biological research concerning cell-specific temporal studies, e.g., non-destructive sampling and analysis of intracellular molecules. Need For Techniques To Study Adherent Cells A mechanistic understanding of cell biology is often limited by both the complexity of the processes and limitations of commonly available research tools that lack temporal or spatial resolution. The lack of tools capable of providing cell-specific, non-destructive biomolecular delivery and analysis is a particular barrier for advancing fundamental discoveries of cell heterogeneity, single-cell behavior within a complex environment, and the mechanisms that govern disease states, responses to drugs or other stimuli, and differentiation of stem cells. To gain new mechanistic understanding, advances in methods for precise intracellular delivery and non-destructive biochemical analyses of non-secretory molecules (e.g., mRNA and proteins) are greatly needed so that individual cells can be experimentally controlled and repeatedly analyzed over time and/or within a particular location of the cell. For example, developing neurons must undergo a series of sequential changes in gene expression to achieve a mature phenotype; hence, understanding the process will require the ability to accurately monitor the sequence of intracellular events, within individual cells, in a non-destructive manner. In addition, neuronal maturation is influenced by interactions with surrounding cells and with extracellular matrix, so it is necessary to be able to simultaneously monitor events occurring in multiple cells that are interacting with each other and with the matrix. While the requirements are challenging, these experimental capabilities would provide unprecedented insight into the determinants of both the timing of cellular processes and their phenotype, the principles of cell heterogeneity, and the role of cell-cell communication in homogeneous cell populations and co-cultures. Because most cells adhere to a substrate or to other cells during their growth or differentiation [1], it is advantageous for new technologies to be capable of accessing adhered cells to avoid the need to disrupt cell processes by suspension and replating. Several technologies for studying adhered cells are currently being developed, and due to the need for individual cell access and non-destructive probing, micro- and nano-technologies are a natural choice because they interact with cells at the appropriate length scale, reduce the working volume of expensive reagents, require less time and space for replicates, allow for automation and integration of sequential analyses, enable portability, and reduce waste [2, 3]. Here we present an overview of recently developed micro- and nano-tools, with a focus on trends in intracellular delivery for in vitro studies of adhered cells, and highlight major advantages/disadvantages of these technologies with respect to features such as individual cell selectivity, spatial resolution, non-destructive cell analysis, and potential for high throughput or automation. Finally, we discuss the exciting promise for these technologies to cause a paradigm shift in biological research by providing methods to study cells over time at the individual cell level. PMID:27287927

Multilamellar Structures and Filament Bundles Are Found on the Cell Surface during Bunyavirus Egress

PubMed Central

Sanz-Sánchez, Laura; Risco, Cristina

2013-01-01

Inside cells, viruses build specialized compartments for replication and morphogenesis. We observed that virus release associates with specific structures found on the surface of mammalian cells. Cultured adherent cells were infected with a bunyavirus and processed for oriented sectioning and transmission electron microscopy. Imaging of cell basal regions showed sophisticated multilamellar structures (MLS) and extracellular filament bundles with attached viruses. Correlative light and electron microscopy confirmed that both MLS and filaments proliferated during the maximum egress of new viruses. MLS dimensions and structure were reminiscent of those reported for the nanostructures on gecko fingertips, which are responsible for the extraordinary attachment capacity of these lizards. As infected cells with MLS were more resistant to detachment than control cells, we propose an adhesive function for these structures, which would compensate for the loss of adherence during release of new virus progeny. PMID:23799021

Stationary nanoliter droplet array with a substrate of choice for single adherent/nonadherent cell incubation and analysis.

PubMed

Shemesh, Jonathan; Ben Arye, Tom; Avesar, Jonathan; Kang, Joo H; Fine, Amir; Super, Michael; Meller, Amit; Ingber, Donald E; Levenberg, Shulamit

2014-08-05

Microfluidic water-in-oil droplets that serve as separate, chemically isolated compartments can be applied for single-cell analysis; however, to investigate encapsulated cells effectively over prolonged time periods, an array of droplets must remain stationary on a versatile substrate for optimal cell compatibility. We present here a platform of unique geometry and substrate versatility that generates a stationary nanodroplet array by using wells branching off a main microfluidic channel. These droplets are confined by multiple sides of a nanowell and are in direct contact with a biocompatible substrate of choice. The device is operated by a unique and reversed loading procedure that eliminates the need for fine pressure control or external tubing. Fluorocarbon oil isolates the droplets and provides soluble oxygen for the cells. By using this approach, the metabolic activity of single adherent cells was monitored continuously over time, and the concentration of viable pathogens in blood-derived samples was determined directly by measuring the number of colony-formed droplets. The method is simple to operate, requires a few microliters of reagent volume, is portable, is reusable, and allows for cell retrieval. This technology may be particularly useful for multiplexed assays for which prolonged and simultaneous visual inspection of many isolated single adherent or nonadherent cells is required.

Stationary nanoliter droplet array with a substrate of choice for single adherent/nonadherent cell incubation and analysis

PubMed Central

Shemesh, Jonathan; Ben Arye, Tom; Avesar, Jonathan; Kang, Joo H.; Fine, Amir; Super, Michael; Meller, Amit; Ingber, Donald E.; Levenberg, Shulamit

2014-01-01

Microfluidic water-in-oil droplets that serve as separate, chemically isolated compartments can be applied for single-cell analysis; however, to investigate encapsulated cells effectively over prolonged time periods, an array of droplets must remain stationary on a versatile substrate for optimal cell compatibility. We present here a platform of unique geometry and substrate versatility that generates a stationary nanodroplet array by using wells branching off a main microfluidic channel. These droplets are confined by multiple sides of a nanowell and are in direct contact with a biocompatible substrate of choice. The device is operated by a unique and reversed loading procedure that eliminates the need for fine pressure control or external tubing. Fluorocarbon oil isolates the droplets and provides soluble oxygen for the cells. By using this approach, the metabolic activity of single adherent cells was monitored continuously over time, and the concentration of viable pathogens in blood-derived samples was determined directly by measuring the number of colony-formed droplets. The method is simple to operate, requires a few microliters of reagent volume, is portable, is reusable, and allows for cell retrieval. This technology may be particularly useful for multiplexed assays for which prolonged and simultaneous visual inspection of many isolated single adherent or nonadherent cells is required. PMID:25053808

Silk screen based dual spin-filter module for perfusion culture of adherent and non-adherent mammalian cells.

PubMed

Kamthan, Shweta; Gomes, James; Roychoudhury, Pradip K

2014-08-01

Spin-filters have been primarily used for producing therapeutic proteins from mammalian cells. However, disposability and/or high filter clogging of the existing spin-filter systems affect the process economy and productivity. Hence, to address these drawbacks a reusable dual spin-filter module for perfusion culture of adherent and non-adherent mammalian cells was designed. Two non-woven Bombyx mori silk layers were used as filter screen; the outer layer was conducive to cell attachment whilst the inner was non-conducive. Adherent cells can be cultured either in suspended mode using its inner single module or as monolayer of cells using its dual concentric module. We achieved 30 % higher urokinase productivity as compared to the stainless-steel spin-filter during perfusion experiments of adherent human kidney cells in suspended mode. This was due to the hydrophobic and negatively-charged silk screen that allows clog-free perfusion culture for prolonged periods.

Receptor-mediated binding of IgE-sensitized rat basophilic leukemia cells to antigen-coated substrates under hydrodynamic flow.

PubMed Central

Tempelman, L A; Hammer, D A

1994-01-01

The physiological function of many cells is dependent on their ability to adhere via receptors to ligand-coated surfaces under fluid flow. We have developed a model experimental system to measure cell adhesion as a function of cell and surface chemistry and fluid flow. Using a parallel-plate flow chamber, we measured the binding of rat basophilic leukemia cells preincubated with anti-dinitrophenol IgE antibody to polyacrylamide gels covalently derivatized with 2,4-dinitrophenol. The rat basophilic leukemia cells' binding behavior is binary: cells are either adherent or continue to travel at their hydrodynamic velocity, and the transition between these two states is abrupt. The spatial location of adherent cells shows cells can adhere many cell diameters down the length of the gel, suggesting that adhesion is a probabilistic process. The majority of experiments were performed in the excess ligand limit in which adhesion depends strongly on the number of receptors but weakly on ligand density. Only 5-fold changes in IgE surface density or in shear rate were necessary to change adhesion from complete to indistinguishable from negative control. Adhesion showed a hyperbolic dependence on shear rate. By performing experiments with two IgE-antigen configurations in which the kinetic rates of receptor-ligand binding are different, we demonstrate that the forward rate of reaction of the receptor-ligand pair is more important than its thermodynamic affinity in the regulation of binding under hydrodynamic flow. In fact, adhesion increases with increasing receptor-ligand reaction rate or decreasing shear rate, and scales with a single dimensionless parameter which compares the relative rates of reaction to fluid shear. Images FIGURE 2 FIGURE 3 FIGURE 6 FIGURE 8 FIGURE 10 PMID:8038394

Aeromonas species exhibit aggregative adherence to HEp-2 cells.

PubMed Central

Neves, M S; Nunes, M P; Milhomem, A M

1994-01-01

Clinical and environmental isolates of Aeromonas species (five A. hydrophila isolates, three A. caviae isolates, and two A. sobria isolates) were tested for their adherence to HEp-2 cells. Clinical isolates of A. hydrophila and A. sobria exhibited aggregative adherence similar to that presented by enteroadherent-aggregative Escherichia coli. Bacterial aggregates adhered to cells with a typical "stacked-brick" appearance. In contrast, A. caviae strains showed a diffuse adherence pattern. Images PMID:8027331

A mannose-specific adherence mechanism in Lactobacillus plantarum conferring binding to the human colonic cell line HT-29.

PubMed

Adlerberth, I; Ahrne, S; Johansson, M L; Molin, G; Hanson, L A; Wold, A E

1996-07-01

Two Lactobacillus plantarum strains of human intestinal origin, strains 299 (= DSM 6595) and 299v (= DSM 9843), have proved to be efficient colonizers of the human intestine under experimental conditions. These strains and 17 other L. plantarum strains were tested for the ability to adhere to cells of the human colonic cell line HT-29.L.plantarum 299 and 299v and nine other L. plantarum strains, including all six strains that belong to the same genetic subgroup as L. plantarum 299 and 299v, adhered to HT-29 cells in a manner that could be inhibited by methyl-alpha-D-mannoside. The ability to adhere to HT-29 cells correlated with an ability to agglutinate cells of Saccharomyces cerevisiae and erythrocytes in a mannose-sensitive manner and with adherence to D-mannose-coated agarose beads. L. plantarum 299 and 299v adhered to freshly isolated human colonic and ileal enterocytes, but the binding was not significantly inhibited by methyl-alpha-D-mannoside. Periodate treatment of HT-29 cells abolished mannose-sensitive adherence, confirming that the cell-bound receptor was of carbohydrate nature. Proteinase K treatment of the bacteria also abolished adherence, indicating that the binding involved protein structures on the bacterial cell surface. Thus, a mannose-specific adhesin has been identified in L. plantarum; this adhesin could be involved in the ability to colonize the intestine.

Lipogels: surface-adherent composite hydrogels assembled from poly(vinyl alcohol) and liposomes

NASA Astrophysics Data System (ADS)

Jensen, Bettina E. B.; Hosta-Rigau, Leticia; Spycher, Philipp R.; Reimhult, Erik; Städler, Brigitte; Zelikin, Alexander N.

2013-07-01

Drug-eluting engineered surface coatings are of paramount importance for many biomedical applications from implantable devices to tissue engineering. Herein, we present the assembly of lipogels, composite physical hydrogels assembled from poly(vinyl alcohol) and liposomes using thiol-disulfide exchange between end group modified PVA and thiocholesterol containing liposomes, and the response of adhering cells to these coatings. We demonstrate the controlled loading of liposomes into the polymer matrix and the preserved mechanical properties of the lipogels. Furthermore, the lipogels are successfully rendered cell adhesive by incorporation of poly(l-lysine) into the PVA polymer matrix or by poly(dopamine) coating of the lipogels. The successful lipid uptake from the lipogels by macrophages, hepatocytes, and myoblasts was monitored by flow cytometry. Finally, the delivery of active cargo, paclitaxel, to adherent myoblasts is shown, thus illustrating the potential of the lipogels as a drug eluting interface for biomedical applications.Drug-eluting engineered surface coatings are of paramount importance for many biomedical applications from implantable devices to tissue engineering. Herein, we present the assembly of lipogels, composite physical hydrogels assembled from poly(vinyl alcohol) and liposomes using thiol-disulfide exchange between end group modified PVA and thiocholesterol containing liposomes, and the response of adhering cells to these coatings. We demonstrate the controlled loading of liposomes into the polymer matrix and the preserved mechanical properties of the lipogels. Furthermore, the lipogels are successfully rendered cell adhesive by incorporation of poly(l-lysine) into the PVA polymer matrix or by poly(dopamine) coating of the lipogels. The successful lipid uptake from the lipogels by macrophages, hepatocytes, and myoblasts was monitored by flow cytometry. Finally, the delivery of active cargo, paclitaxel, to adherent myoblasts is shown, thus illustrating the potential of the lipogels as a drug eluting interface for biomedical applications. Electronic supplementary information (ESI) available: Paclitaxel calibration curve and images of DIC of PLL blended PVA physical hydrogels, lipogel FRAP, and different cell lines attached to lipogels are available. See DOI: 10.1039/c3nr01662e

Optical spectrum measurement of a cell-adhered microcavity for the cell-cycle analysis applications

NASA Astrophysics Data System (ADS)

Saito, Ryusuke; Terakawa, Mitsuhiro; Tanabe, Takasumi

2015-03-01

We build a setup and demonstrate successful measurement of the transmittance spectrum of a whispering gallery mode silica optical microcavity in which NIH 3T3 cells adhered on the top surface to achieve real-time and label-free measurement of the cell cycle. Label-free measurement is expected to prevent the cells to exhibit secondary effect. We build a system that enables the control of the gap distance between the microcavity and the tapered fiber, both of which are placed in the cell culture medium. The optimization of the tapered fiber diameter is the key to measure the spectrum of a microcavity in liquid. A swept wavelength laser light at a wavelength of 766 to 780 nm is used for the measurement. The cavity exhibit a Q of 1 . 0 ×106 in air, where the value is 1 . 0 ×105 in the medium and drops to 3 . 1 ×104 after the cell-adhesion. Still the Q of the microcavity is sufficiently high to detect the change at the cavity surface. Indeed we observe slight spectrum shift toward a longer wavelength, which we believe is due to the adherence of NIH 3T3 cells on the silica microcavity.The successful measurement of the transmittance spectrum of a microcavity in cell culture medium is the first step to realize the analysis of the cell-cycle based on microcavity system.

Electrochemical push-pull probe: from scanning electrochemical microscopy to multimodal altering of cell microenvironment.

PubMed

Bondarenko, Alexandra; Cortés-Salazar, Fernando; Gheorghiu, Mihaela; Gáspár, Szilveszter; Momotenko, Dmitry; Stanica, Luciana; Lesch, Andreas; Gheorghiu, Eugen; Girault, Hubert H

2015-04-21

To understand biological processes at the cellular level, a general approach is to alter the cells' environment and to study their chemical responses. Herein, we present the implementation of an electrochemical push-pull probe, which combines a microfluidic system with a microelectrode, as a tool for locally altering the microenvironment of few adherent living cells by working in two different perturbation modes, namely electrochemical (i.e., electrochemical generation of a chemical effector compound) and microfluidic (i.e., infusion of a chemical effector compound from the pushing microchannel, while simultaneously aspirating it through the pulling channel, thereby focusing the flow between the channels). The effect of several parameters such as flow rate, working distance, and probe inclination angle on the affected area of adherently growing cells was investigated both theoretically and experimentally. As a proof of concept, localized fluorescent labeling and pH changes were purposely introduced to validate the probe as a tool for studying adherent cancer cells through the control over the chemical composition of the extracellular space with high spatiotemporal resolution. A very good agreement between experimental and simulated results showed that the electrochemical perturbation mode enables to affect precisely only a few living cells localized in a high-density cell culture.

Cell Migration in 1D and 2D Nanofiber Microenvironments.

PubMed

Estabridis, Horacio M; Jana, Aniket; Nain, Amrinder; Odde, David J

2018-03-01

Understanding how cells migrate in fibrous environments is important in wound healing, immune function, and cancer progression. A key question is how fiber orientation and network geometry influence cell movement. Here we describe a quantitative, modeling-based approach toward identifying the mechanisms by which cells migrate in fibrous geometries having well controlled orientation. Specifically, U251 glioblastoma cells were seeded onto non-electrospinning Spinneret based tunable engineering parameters fiber substrates that consist of networks of suspended 400 nm diameter nanofibers. Cells were classified based on the local fiber geometry and cell migration dynamics observed by light microscopy. Cells were found in three distinct geometries: adhering two a single fiber, adhering to two parallel fibers, and adhering to a network of orthogonal fibers. Cells adhering to a single fiber or two parallel fibers can only move in one dimension along the fiber axis, whereas cells on a network of orthogonal fibers can move in two dimensions. We found that cells move faster and more persistently in 1D geometries than in 2D, with cell migration being faster on parallel fibers than on single fibers. To explain these behaviors mechanistically, we simulated cell migration in the three different geometries using a motor-clutch based model for cell traction forces. Using nearly identical parameter sets for each of the three cases, we found that the simulated cells naturally replicated the reduced migration in 2D relative to 1D geometries. In addition, the modestly faster 1D migration on parallel fibers relative to single fibers was captured using a correspondingly modest increase in the number of clutches to reflect increased surface area of adhesion on parallel fibers. Overall, the integrated modeling and experimental analysis shows that cell migration in response to varying fibrous geometries can be explained by a simple mechanical readout of geometry via a motor-clutch mechanism.

Epidemiology of Pneumocystis carinii pneumonia in an era of effective prophylaxis: the relative contribution of non-adherence and drug failure.

PubMed

Lundberg, B E; Davidson, A J; Burman, W J

2000-11-10

To determine the relative contribution of patient non-adherence, provider failure to prescribe prophylaxis, and drug failure to the continued occurrence of Pneumocystis carinii pneumonia (PCP), and to determine correlates of non-adherence. Retrospective case-control study. Patients with confirmed or presumptive PCP from May 1995 to September 1997 who had at least 6 months of prior HIV care (cases) were compared to controls matched for initial CD4 cell count and date of initial HIV care. The incidence of PCP declined by 85% in the 28 months of the study. Of the 118 cases of PCP identified, 59 (50%) were in HIV care for > 6 months prior to PCP diagnosis. In a multivariate logistic regression model, risk factors for PCP among patients in HIV care were patient non-adherence [odds ratio (OR), 12.4; 95% confidence interval (CI), 6.4-23.5], use of prophylaxis other than trimethoprim-sulfamethoxazole (OR, 27.0; 95% CI, 13.8-52.9), and absence of antiretroviral use (OR, 7.5; 95% CI, 4.5-12.5). Provider non-adherence occurred in one out of 59 cases (2%), and five out of 106 controls (5%). Of the patients who developed PCP on prophylaxis, 18 cases (30%) appeared due to drug failure; there were no cases of apparent drug failure among patients on trimethoprim-sulfamethoxazole. In multivariate analysis, non-adherence was more common among patients of non-white race, those with a history of injecting drug use, and those with active substance abuse or psychiatric illness. Patient non-adherence was the most common reason for the occurrence of PCP among patients in HIV care; provider non-adherence was uncommon. Drug failure occurred only among patients on prophylaxis other than trimethoprim-sulfamethoxazole.

Inactivation of Clostridium perfringens spores adhered onto stainless steel surface by agents used in a clean-in-place procedure.

PubMed

Alzubeidi, Yasmeen S; Udompijitkul, Pathima; Talukdar, Prabhat K; Sarker, Mahfuzur R

2018-07-20

Enterotoxigenic Clostridium perfringens, a leading foodborne pathogen can be cross-contaminated from food processing stainless steel (SS) surfaces to the finished food products. This is mostly due to the high resistance of C. perfringens spores adhered onto SS surfaces to various disinfectants commonly used in food industries. In this study, we aimed to investigate the survivability and adherence of C. perfringens spores onto SS surfaces and then validate the effectiveness of a simulated Clean-in-Place (CIP) regime on inactivation of spores adhered onto SS surfaces. Our results demonstrated that, 1) C. perfringens spores adhered firmly onto SS surfaces and survived for at-least 48 h, unlike their vegetative cells who died within 30 min, after aerobic incubation at refrigerated and ambient temperatures; 2) Spores exhibited higher levels of hydrophobicity than vegetative cells, suggesting a correlation between cell surface hydrophobicity and adhesion to solid surfaces; 3) Intact spores were more hydrophobic than the decoated spores, suggesting a positive role of spore coat components on spores' hydrophobicity and thus adhesion onto SS surfaces; and finally 4) The CIP regime (NaOH + HNO 3 ) successfully inactivated C. perfringens spores adhered onto SS surfaces, and most of the effect of CIP regime appeared to be due to the NaOH. Collectively, our current findings may well contribute towards developing a strategy to control cross-contamination of C. perfringens spores into food products, which should help reducing the risk of C. perfringens-associated food poisoning outbreaks. Copyright © 2018 Elsevier B.V. All rights reserved.

A bio-inspired, microchanneled hydrogel with controlled spacing of cell adhesion ligands regulates 3D spatial organization of cells and tissue.

PubMed

Lee, Min Kyung; Rich, Max H; Lee, Jonghwi; Kong, Hyunjoon

2015-07-01

Bioactive hydrogels have been extensively studied as a platform for 3D cell culture and tissue regeneration. One of the key desired design parameters is the ability to control spatial organization of biomolecules and cells and subsequent tissue in a 3D matrix. To this end, this study presents a simple but advanced method to spatially organize microchanneled, cell adherent gel blocks and non-adherent ones in a single construct. This hydrogel system was prepared by first fabricating a bimodal hydrogel in which the microscale, alginate gel blocks modified with cell adhesion peptides containing Arg-Gly-Asp sequence (RGD peptides), and those free of RGD peptides, were alternatingly presented. Then, anisotropically aligned microchannels were introduced by uniaxial freeze-drying of the bimodal hydrogel. The resulting gel system could drive bone marrow stromal cells to adhere to and differentiate into neuron and glial cells exclusively in microchannels of the alginate gel blocks modified with RGD peptides. Separately, the bimodal gel loaded with microparticles releasing vascular endothelial growth factor stimulated vascular growth solely into microchannels of the RGD-alginate gel blocks in vivo. These results were not attained by the bimodal hydrogel fabricated to present randomly oriented micropores. Overall, the bimodal gel system could regulate spatial organization of nerve-like tissue or blood vessels at sub-micrometer length scale. We believe that the hydrogel assembly demonstrated in this study will be highly useful in developing a better understanding of diverse cellular behaviors in 3D tissue and further improve quality of a wide array of engineered tissues. Copyright © 2015 Elsevier Ltd. All rights reserved.

Purified Dendritic Cell-Tumor Fusion Hybrids Supplemented with Non-Adherent Dendritic Cells Fraction Are Superior Activators of Antitumor Immunity

PubMed Central

Wang, Yucai; Liu, Yunyan; Zheng, Lianhe

2014-01-01

Background Strong evidence supports the DC-tumor fusion hybrid vaccination strategy, but the best fusion product components to use remains controversial. Fusion products contain DC-tumor fusion hybrids, unfused DCs and unfused tumor cells. Various fractions have been used in previous studies, including purified hybrids, the adherent cell fraction or the whole fusion mixture. The extent to which the hybrids themselves or other components are responsible for antitumor immunity or which components should be used to maximize the antitumor immunity remains unknown. Methods Patient-derived breast tumor cells and DCs were electro-fused and purified. The antitumor immune responses induced by the purified hybrids and the other components were compared. Results Except for DC-tumor hybrids, the non-adherent cell fraction containing mainly unfused DCs also contributed a lot in antitumor immunity. Purified hybrids supplemented with the non-adherent cell population elicited the most powerful antitumor immune response. After irradiation and electro-fusion, tumor cells underwent necrosis, and the unfused DCs phagocytosed the necrotic tumor cells or tumor debris, which resulted in significant DC maturation. This may be the immunogenicity mechanism of the non-adherent unfused DCs fraction. Conclusions The non-adherent cell fraction (containing mainly unfused DCs) from total DC/tumor fusion products had enhanced immunogenicity that resulted from apoptotic/necrotic tumor cell phagocytosis and increased DC maturation. Purified fusion hybrids supplemented with the non-adherent cell population enhanced the antitumor immune responses, avoiding unnecessary use of the tumor cell fraction, which has many drawbacks. Purified hybrids supplemented with the non-adherent cell fraction may represent a better approach to the DC-tumor fusion hybrid vaccination strategy. PMID:24466232

Photosensitizer adhered to cell culture microplates induces phototoxicity in carcinoma cells.

PubMed

Ziegler, Verena; Kiesslich, Tobias; Krammer, Barbara; Plaetzer, Kristjan

2013-01-01

In vitro experiments in plastic receptacles are the basis of characterization of new photosensitizers (PSs) for the photodynamic therapy. We recently reported that lipophilic PSs adhere to cell culture microplates in a kinetic-like manner (Engelhardt et al., 2011). In the current study, we examined the interaction and phototoxic effects of the microplate-adhered PS in cancer cells. Therefore, we preloaded microplates with hypericin, Foscan, PVP-hypericin, or aluminum (III) phthalocyanine tetrasulfonate chloride (AlPCS4) for 24 hours and measured the PS distribution after addition of A431 human carcinoma cells: following another 24 hours up to 68% of hypericin were detected in the cell fraction. The hydrophilic PVP-hypericin and AlPCS4 also diffused into the cells, but the quantities of PS adherence were considerably lower. Microplate-adhered Foscan appeared not to be redistributed. In contrast to the hydrophilic PSs, the cellular phototoxicity of microplate-adhered lipophilic PS was high, independent of whether the PS (i) was pre-loaded onto microplates or (ii) added simultaneously with the cells or (iii) one day after cell seeding. Based on these results, we suggest testing lipophilic PS dyes for their adherence to microplates. Furthermore, the ability of plastic materials to (reversibly) store PSs might represent a new approach for the PS delivery or the development of antimicrobial coatings.

Photosensitizer Adhered to Cell Culture Microplates Induces Phototoxicity in Carcinoma Cells

PubMed Central

Ziegler, Verena; Kiesslich, Tobias; Krammer, Barbara; Plaetzer, Kristjan

2013-01-01

In vitro experiments in plastic receptacles are the basis of characterization of new photosensitizers (PSs) for the photodynamic therapy. We recently reported that lipophilic PSs adhere to cell culture microplates in a kinetic-like manner (Engelhardt et al., 2011). In the current study, we examined the interaction and phototoxic effects of the microplate-adhered PS in cancer cells. Therefore, we preloaded microplates with hypericin, Foscan, PVP-hypericin, or aluminum (III) phthalocyanine tetrasulfonate chloride (AlPCS4) for 24 hours and measured the PS distribution after addition of A431 human carcinoma cells: following another 24 hours up to 68% of hypericin were detected in the cell fraction. The hydrophilic PVP-hypericin and AlPCS4 also diffused into the cells, but the quantities of PS adherence were considerably lower. Microplate-adhered Foscan appeared not to be redistributed. In contrast to the hydrophilic PSs, the cellular phototoxicity of microplate-adhered lipophilic PS was high, independent of whether the PS (i) was pre-loaded onto microplates or (ii) added simultaneously with the cells or (iii) one day after cell seeding. Based on these results, we suggest testing lipophilic PS dyes for their adherence to microplates. Furthermore, the ability of plastic materials to (reversibly) store PSs might represent a new approach for the PS delivery or the development of antimicrobial coatings. PMID:23509741

Cell Phone Intervention to Improve Adherence

PubMed Central

Marciel, Kristen K.; Saiman, Lisa; Quittell, Lynne M.; Dawkins, Kevin; Quittner, Alexandra L.

2010-01-01

Summary Background Treatment regimens for patients with cystic fibrosis (CF) are time-consuming and complex, resulting in consistently low adherence rates. To date, few studies have evaluated innovative technologies to improve adherence in this population. Current infection control guidelines for patients with CF seek to minimize patient-to-patient transmission of potential pathogens. Thus, interventions must avoid face-to-face contact and be delivered individually, limiting opportunities for peer support. This study aimed to develop and assess a web-enabled cell phone, CFFONE™, designed to provide CF information and social support to improve adherence in adolescents with CF. Methods The acceptability, feasibility, and utility of CFFONE™ were evaluated with health care professionals (n = 17) adolescents with CF aged 11–18 years old (n = 12), adults with CF aged 21–36 years old (n = 6), parents of adolescents with CF (n = 12), and technology experts (n = 8). Adolescents also tested a prototype of CFFONE™ (n = 9). Qualitative and quantitative data were collected. Results Focus group data with health care = professionals indicated a need for this intervention, and indicated that CFFONE™ would be likely to improve knowledge and social support, and somewhat likely to improve adherence. Adolescent, adults, and parents all rated CFFONE™ as likely to improve adherence. Technology experts rated the prototype design and format as appropriate. Conclusions The current study provided some support from key stakeholders for this intervention to improve adherence in adolescents with CF. Next steps include a multi-center trial of the efficacy and safety of CFFONE™. PMID:20054860

Neonatal rat heart cells cultured in simulated microgravity

NASA Technical Reports Server (NTRS)

Akins, Robert E.; Schroedl, Nancy A.; Gonda, Steve R.; Hartzell, Charles R.

1994-01-01

In vitro characteristics of cardiac cells cultured in simulated microgravity are reported. Tissue culture methods performed at unit gravity constrain cells to propagate, differentiate, and interact in a two dimensional (2D) plane. Neonatal rat cardiac cells in 2D culture organize predominantly as bundles of cardiomyocytes with the intervening areas filled by non-myocyte cell types. Such cardiac cell cultures respond predictably to the addition of exogenous compounds, and in many ways they represent an excellent in vitro model system. The gravity-induced 2D organization of the cells, however, does not accurately reflect the distribution of cells in the intact tissue. We have begun characterizations of a three-dimensional (3D) culturing system designed to mimic microgravity. The NASA designed High-Aspect-Ratio-Vessel (HARV) bioreactors provide a low shear environment which allows cells to be cultured in static suspension. HARV-3D cultures were prepared on microcarrier beads and compared to control-2D cultures using a combination of microscopic and biochemical techniques. Both systems were uniformly inoculated and medium exchanged at standard intervals. Cells in control cultures adhered to the polystyrene surface of the tissue culture dishes and exhibited typical 2D organization. Cells in cultured in HARV's adhered to microcarrier beads, the beads aggregated into defined clusters containing 8 to 15 beads per cluster, and the clusters exhibited distinct 3D layers: myocytes and fibroblasts appeared attached to the surfaces of beads and were overlaid by an outer cell type. In addition, cultures prepared in HARV's using alternative support matrices also displayed morphological formations not seen in control cultures. Generally, the cells prepared in HARV and control cultures were similar, however, the dramatic alterations in 3D organization recommend the HARV as an ideal vessel for the generation of tissue-like organizations of cardiac cells in simulated microgravity.

Neonatal rat heart cells cultured in simulated microgravity

NASA Technical Reports Server (NTRS)

Akins, R. E.; Schroedl, N. A.; Gonda, S. R.; Hartzell, C. R.

1997-01-01

In vitro characteristics of cardiac cells cultured in simulated microgravity are reported. Tissue culture methods performed at unit gravity constrain cells to propagate, differentiate, and interact in a two-dimensional (2D) plane. Neonatal rat cardiac cells in 2D culture organize predominantly as bundles of cardiomyocytes with the intervening areas filled by nonmyocyte cell types. Such cardiac cell cultures respond predictably to the addition of exogenous compounds, and in many ways they represent an excellent in vitro model system. The gravity-induced 2D organization of the cells, however, does not accurately reflect the distribution of cells in the intact tissue. We have begun characterizations of a three-dimensional (3D) culturing system designed to mimic microgravity. The NASA-designed High-Aspect Ratio Vessel (HARV) bioreactors provide a low shear environment that allows cells to be cultured in static suspension. HARV-3D cultures were prepared on microcarrier beads and compared to control-2D cultures using a combination of microscopic and biochemical techniques. Both systems were uniformly inoculated and medium exchanged at standard intervals. Cells in control cultures adhered to the polystyrene surface of the tissue culture dishes and exhibited typical 2D organization. Cells cultured in HARVs adhered to microcarrier beads, the beads aggregated into defined clusters containing 8 to 15 beads per cluster, and the clusters exhibited distinct 3D layers: myocytes and fibroblasts appeared attached to the surfaces of beads and were overlaid by an outer cell type. In addition, cultures prepared in HARVs using alternative support matrices also displayed morphological formations not seen in control cultures. Generally, the cells prepared in HARV and control cultures were similar; however, the dramatic alterations in 3D organization recommend the HARV as an ideal vessel for the generation of tissuelike organization of cardiac cells in vitro.

Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs): Positive and negative regulators in tumor cell adhesion.

PubMed

Bourboulia, Dimitra; Stetler-Stevenson, William G

2010-06-01

Cells adhere to one another and/or to matrices that surround them. Regulation of cell-cell (intercellular) and cell-matrix adhesion is tightly controlled in normal cells, however, defects in cell adhesion are common in the majority of human cancers. Multilateral communication among tumor cells with the extracellular matrix (ECM) and neighbor cells is accomplished through adhesion molecules, ECM components, proteolytic enzymes and their endogenous inhibitors. There is sufficient evidence to suggest that reduced adherence is a tumor cell property engaged during tumor progression. Tumor cells acquire the ability to change shape, detach and easily move through spaces disorganizing the normal tissue architecture. This property is due to changes in expression levels of adhesion molecules and/or due to elevated levels of secreted proteolytic enzymes, including matrix metalloproteinases (MMPs). Among other roles, MMPs degrade the ECM and, therefore, prepare the path for tumor cells to migrate, invade and spread to distant secondary areas, where they form metastasis. Tissue inhibitors of metalloproteinases or TIMPs control MMP activities and, therefore, minimize matrix degradation. Both MMPs and TIMPs are involved in tissue remodeling and decisively regulate tumor cell progression including tumor angiogenesis. In this review, we describe and discuss data that support the important role of MMPs and TIMPs in cancer cell adhesion and tumor progression. Published by Elsevier Ltd.

Soft tissue cell adhesion to titanium abutments after different cleaning procedures: Preliminary results of a randomized clinical trial

PubMed Central

Canullo, Luigi; Peñarrocha-Oltra, David; Marchionni, Silvia; Bagán, Leticia; Micarelli, Costanza

2014-01-01

Objectives: A randomized controlled trial was performed to assess soft tissue cell adhesion to implant titanium abutments subjected to different cleaning procedures and test if plasma cleaning can enhance cell adhesion at an early healing time. Study Design: Eighteen patients with osseointegrated and submerged implants were included. Before re-opening, 18 abutments were divided in 3 groups corresponding to different clinical conditions with different cleaning processes: no treatment (G1), laboratory customization and cleaning by steam (G2), cleaning by plasma of Argon (G3). Abutments were removed after 1 week and scanning electron microscopy was used to analyze cell adhesion to the abutment surface quantitatively (percentage of area occupied by cells) and qualitatively (aspect of adhered cells and presence of contaminants). Results: Mean percentages of area occupied by cells were 17.6 ± 22.7%, 16.5 ± 12.9% and 46.3 ± 27.9% for G1, G2 and G3 respectively. Differences were statistically significant between G1 and G3 (p=0.030), close to significance between G2 and G3 (p=0.056), and non-significant between G1 and G2 (p=0.530). The proportion of samples presenting adhered cells was homogeneous among the 3 groups (p-valor = 1.000). In all cases cells presented a flattened aspect; in 2 cases cells were less efficiently adhered and in 1 case cells presented filipodia. Three cases showed contamination with cocobacteria. Conclusions: Within the limits of the present study, plasma of Argon may enhance cell adhesion to titanium abutments, even at the early stage of soft tissue healing. Further studies with greater samples are necessary to confirm these findings. Key words:Connective tissue, dental abutments, randomized controlled trial, clinical research, glow discharged abutment, plasma cleaning. PMID:24121917

Adherence to Antiretroviral Therapy (ART) in Yaoundé-Cameroon: Association with Opportunistic Infections, Depression, ART Regimen and Side Effects

PubMed Central

Fonsah, Julius Y.; Njamnshi, Alfred K.; Kouanfack, Charles; Qiu, Fang; Njamnshi, Dora M.; Tagny, Claude T.; Nchindap, Emilienne; Kenmogne, Léopoldine; Mbanya, Dora; Heaton, Robert; Kanmogne, Georgette D.

2017-01-01

Following global efforts to increase antiretroviral therapy (ART) access in Sub-Saharan Africa, ART coverage among HIV-infected Cameroonians increased from 0% in 2003 to 22% in 2014. However, the success of current HIV treatment programs depends not only on access to ART, but also on retention in care and good treatment adherence. This is necessary to achieve viral suppression, prevent virologic failure, and reduce viral transmission and HIV/AIDS-related deaths. Previous studies in Cameroon showed poor adherence, treatment interruption, and loss to follow-up among HIV+ subjects on ART, but the factors that influence ART adherence are not well known. In the current cross-sectional study, patient/self-reported questionnaires and pharmacy medication refill data were used to quantify ART adherence and determine the factors associated with increased risk of non-adherence among HIV-infected Cameroonians. We demonstrated that drug side-effects, low CD4 cell counts and higher viral loads are associated with increased risk of non-adherence, and compared to females, males were more likely to forego ART because of side effects (p<0.05). Univariate logistic regression analysis demonstrated that subjects with opportunistic infections (on antibiotics) had 2.42-times higher odds of having been non-adherent (p<0.001). Multivariable analysis controlling for ART regimen, age, gender, and education showed that subjects with opportunistic infections had 3.1-times higher odds of having been non-adherent (p<0.0003), with significantly longer periods of non-adherence, compared to subjects without opportunistic infections (p = 0.02). We further showed that compared to younger subjects (≤40 years), older subjects (>40 years) were less likely to be non-adherent (p<0.01) and had shorter non-adherent periods (p<0.0001). The presence of depression symptoms correlated with non-adherence to ART during antibiotic treatment (r = 0.53, p = 0.04), and was associated with lower CD4 cell counts (p = 0.04) and longer non-adherent periods (p = 0.04). Change in ART regimen was significantly associated with increased likelihood of non-adherence and increased duration of the non-adherence period. Addressing these underlying risk factors could improve ART adherence, retention in care and treatment outcomes for HIV/AIDS patients in Cameroon. PMID:28141867

Lactobacilli Antagonize the Growth, Motility, and Adherence of Brachyspira pilosicoli: a Potential Intervention against Avian Intestinal Spirochetosis ▿

PubMed Central

Mappley, Luke J.; Tchórzewska, Monika A.; Cooley, William A.; Woodward, Martin J.; La Ragione, Roberto M.

2011-01-01

Avian intestinal spirochetosis (AIS) results from the colonization of the ceca and colorectum of poultry by pathogenic Brachyspira species. The number of cases of AIS has increased since the 2006 European Union ban on the use of antibiotic growth promoters, which, together with emerging antimicrobial resistance in Brachyspira, has driven renewed interest in alternative intervention strategies. Probiotics have been reported as protecting livestock against infection with common enteric pathogens, and here we investigate which aspects of the biology of Brachyspira they antagonize in order to identify possible interventions against AIS. The cell-free supernatants (CFS) of two Lactobacillus strains, Lactobacillus reuteri LM1 and Lactobacillus salivarius LM2, suppressed the growth of Brachyspira pilosicoli B2904 in a pH-dependent manner. In in vitro adherence and invasion assays with HT29-16E three-dimensional (3D) cells and in a novel avian cecal in vitro organ culture (IVOC) model, the adherence and invasion of B. pilosicoli in epithelial cells were reduced significantly by the presence of lactobacilli (P < 0.001). In addition, live and heat-inactivated lactobacilli inhibited the motility of B. pilosicoli, and electron microscopic observations indicated that contact between the lactobacilli and Brachyspira was crucial in inhibiting both adherence and motility. These data suggest that motility is essential for B. pilosicoli to adhere to and invade the gut epithelium and that any interference of motility may be a useful tool for the development of control strategies. PMID:21666022

Cranberry Products Inhibit Adherence of P-Fimbriated Escherichia Coli to Primary Cultured Bladder and Vaginal Epithelial Cells

PubMed Central

Gupta, K.; Chou, M. Y.; Howell, A.; Wobbe, C.; Grady, R.; Stapleton, A. E.

2011-01-01

Purpose Cranberry proanthocyanidins have been identified as possible inhibitors of Escherichia coli adherence to uroepithelial cells. However, little is known about the dose range of this effect. Furthermore, it has not been studied directly in the urogenital system. To address these issues we tested the effect of a cranberry powder and proanthocyanidin extract on adherence of a P-fimbriated uropathogenic E. coli isolate to 2 new urogenital model systems, namely primary cultured bladder epithelial cells and vaginal epithelial cells. Materials and Methods E. coli IA2 was pre-incubated with a commercially available cranberry powder (9 mg proanthocyanidin per gm) or with increasing concentrations of proanthocyanidin extract. Adherence of E. coli IA2 to primary cultured bladder epithelial cells or vaginal epithelial cells was measured before and after exposure to these products. Results Cranberry powder decreased mean adherence of E. coli IA2 to vaginal epithelial cells from 18.6 to 1.8 bacteria per cell (p <0.001). Mean adherence of E. coli to primary cultured bladder epithelial cells was decreased by exposure to 50 μg/ml proanthocyanidin extract from 6.9 to 1.6 bacteria per cell (p <0.001). Inhibition of adherence of E. coli by proanthocyanidin extract occurred in linear, dose dependent fashion over a proanthocyanidin concentration range of 75 to 5 μg/ml. Conclusions Cranberry products can inhibit E. coli adherence to biologically relevant model systems of primary cultured bladder and vaginal epithelial cells. This effect occurs in a dose dependent relationship. These findings provide further mechanistic evidence and biological plausibility for the role of cranberry products for preventing urinary tract infection. PMID:17509358

Cryopreservation of adhered mammalian cells on a microfluidic device: Toward ready-to-use cell-based experimental platforms.

PubMed

Kondo, Eitaro; Wada, Ken-ichi; Hosokawa, Kazuo; Maeda, Mizuo

2016-01-01

In this paper, we describe cryopreservation of mammalian cells in the adhered state on a microfluidic device (microdevice) for the first time. HeLa, NIH3T3, MCF-7, and PC12 cells were cultured on a microdevice in which a commercial polystyrene dish surface was used as the cell adhesion surface. Without cell-detaching treatment, the microdevice was stored in a freezer at -80°C. After thawing, we observed a greater number of live cells on the microdevice than those on a control culture dish. Although the effectiveness of the microdevice varied depending on the cell type and surface coating, the trend was consistent. We confirmed that the phenotype of the PC12 cells to differentiate into neuron-like cells was kept after the on-chip cryopreservation, and that the results of cytotoxicity test of cisplatin against the HeLa cells were essentially unchanged by the on-chip cryopreservation. These findings will open up a new possibility of ready-to-use cell-based experimental platforms. © 2015 Wiley Periodicals, Inc.

Cell Phone-Based and Adherence Device Technologies for HIV Care and Treatment in Resource-Limited Settings: Recent Advances.

PubMed

Campbell, Jeffrey I; Haberer, Jessica E

2015-12-01

Numerous cell phone-based and adherence monitoring technologies have been developed to address barriers to effective HIV prevention, testing, and treatment. Because most people living with HIV and AIDS reside in resource-limited settings (RLS), it is important to understand the development and use of these technologies in RLS. Recent research on cell phone-based technologies has focused on HIV education, linkage to and retention in care, disease tracking, and antiretroviral therapy adherence reminders. Advances in adherence devices have focused on real-time adherence monitors, which have been used for both antiretroviral therapy and pre-exposure prophylaxis. Real-time monitoring has recently been combined with cell phone-based technologies to create real-time adherence interventions using short message service (SMS). New developments in adherence technologies are exploring ingestion monitoring and metabolite detection to confirm adherence. This article provides an overview of recent advances in these two families of technologies and includes research on their acceptability and cost-effectiveness when available. It additionally outlines key challenges and needed research as use of these technologies continues to expand and evolve.

Cognitive behavioral therapy for adherence and depression (CBT-AD) in HIV-infected injection drug users: a randomized controlled trial.

PubMed

Safren, Steven A; O'Cleirigh, Conall M; Bullis, Jacqueline R; Otto, Michael W; Stein, Michael D; Pollack, Mark H

2012-06-01

Depression and substance use, the most common comorbidities with HIV, are both associated with poor treatment adherence. Injection drug users comprise a substantial portion of individuals with HIV in the United States and globally. The present study tested cognitive behavioral therapy for adherence and depression (CBT-AD) in patients with HIV and depression in active substance abuse treatment for injection drug use. This is a 2-arm, randomized controlled trial (N = 89) comparing CBT-AD with enhanced treatment as usual (ETAU). Analyses were conducted for two time-frames: (a) baseline to post-treatment and (b) post-treatment to follow-up at 3 and 6 months after intervention discontinuation. At post-treatment, the CBT-AD condition showed significantly greater improvement than ETAU in MEMS (electronic pill cap) based adherence, γslope = 0.8873, t(86) = 2.38, p = .02; dGMA-raw = 0.64, and depression, assessed by blinded assessor: Mongomery-Asberg Depression Rating Scale, F(1, 79) = 6.52, p < .01, d = 0.55; clinical global impression, F(1, 79) = 14.77, p < .001, d = 0.85. After treatment discontinuation, depression gains were maintained, but adherence gains were not. Viral load did not differ across condition; however, the CBT-AD condition had significant improvements in CD4 cell counts over time compared with ETAU, γslope = 2.09, t(76) = 2.20, p = .03, dGMA-raw = 0.60. In patients managing multiple challenges including HIV, depression, substance dependence, and adherence, CBT-AD is a useful way to integrate treatment of depression with an adherence intervention. Continued adherence counseling is likely needed, however, to maintain or augment adherence gains in this population.

Cold storage of rat hepatocyte suspensions for one week in a customized cold storage solution--preservation of cell attachment and metabolism.

PubMed

Pless-Petig, Gesine; Singer, Bernhard B; Rauen, Ursula

2012-01-01

Primary hepatocytes are of great importance for basic research as well as cell transplantation. However, their stability, especially in suspension, is very low. This feature severely compromises storage and shipment. Based on previous studies with adherent cells, we here assessed cold storage injury in rat hepatocyte suspensions and aimed to find a cold storage solution that preserves viability, attachment ability and functionality of these cells. Rat hepatocyte suspensions were stored in cell culture medium, organ preservation solutions and modified TiProtec solutions at 4°C for one week. Viability and cell volume were determined by flow cytometry. Thereafter, cells were seeded and density and metabolic capacity (reductive metabolism, forskolin-induced glucose release, urea production) of adherent cells were assessed. Cold storage injury in hepatocyte suspensions became evident as cell death occurring during cold storage or rewarming or as loss of attachment ability. Cell death during cold storage was not dependent on cell swelling and was almost completely inhibited in the presence of glycine and L-alanine. Cell attachment could be greatly improved by use of chloride-poor solutions and addition of iron chelators. Using a chloride-poor, potassium-rich storage solution containing glycine, alanine and iron chelators, cultures with 75% of the density of control cultures and with practically normal cell metabolism could be obtained after one week of cold storage. In the solution presented here, cold storage injury of hepatocyte suspensions, differing from that of adherent hepatocytes, was effectively inhibited. The components which acted on the different injurious processes were identified.

Cell phone intervention to improve adherence: cystic fibrosis care team, patient, and parent perspectives.

PubMed

Marciel, Kristen K; Saiman, Lisa; Quittell, Lynne M; Dawkins, Kevin; Quittner, Alexandra L

2010-02-01

Treatment regimens for patients with cystic fibrosis (CF) are time-consuming and complex, resulting in consistently low adherence rates. To date, few studies have evaluated innovative technologies to improve adherence in this population. Current infection control guidelines for patients with CF seek to minimize patient-to-patient transmission of potential pathogens. Thus, interventions must avoid face-to-face contact and be delivered individually, limiting opportunities for peer support. This study aimed to develop and assess a web-enabled cell phone, CFFONE, designed to provide CF information and social support to improve adherence in adolescents with CF. The acceptability, feasibility, and utility of CFFONE were evaluated with health care professionals (n = 17) adolescents with CF aged 11-18 years old (n = 12), adults with CF aged 21-36 years old (n = 6), parents of adolescents with CF (n = 12), and technology experts (n = 8). Adolescents also tested a prototype of CFFONE (n = 9). Qualitative and quantitative data were collected. Focus group data with health care professionals indicated a need for this intervention, and indicated that CFFONE would be likely to improve knowledge and social support, and somewhat likely to improve adherence. Adolescent, adults, and parents all rated CFFONE as likely to improve adherence. Technology experts rated the prototype design and format as appropriate. The current study provided some support from key stakeholders for this intervention to improve adherence in adolescents with CF. Next steps include a multi-center trial of the efficacy and safety of CFFONE. (c) 2010 Wiley-Liss, Inc.

Adherence of Escherichia coli O157:H7 to epithelial cells in vitro and in pig gut loops is affected by bacterial culture conditions

PubMed Central

Yin, Xianhua; Feng, Yanni; Wheatcroft, Roger; Chambers, James; Gong, Joshua; Gyles, Carlton L.

2011-01-01

The objectives of this study were to determine the effect of bacterial culture conditions on adherence of enterohemorrhagic Escherichia coli (EHEC) O157:H7 strain 86-24 in vivo to pig enterocytes and to compare the results with adherence in vitro to cultured HEp-2 and IPEC-J2 cells. Growth of O157:H7 in MacConkey broth (MB) resulted in almost no adherence to both HEp-2 and IPEC-J2 cells; prior exposure of the bacteria to pH 2.5 reduced adherence. There was greater adherence by bacteria from static cultures than by those from shaken cultures and by bacteria cultured in brain–heart infusion (BHI) plus NaHCO3 (BHIN) than by bacteria cultured in BHI. In contrast, in pig ileal loops, bacteria cultured in MB adhered well to enterocytes, and prior exposure to pH 2.5 had no effect on adherence. Among several media tested for their effect on bacterial adherence in the pig intestine, MB and BHIN proved to be the best. Bacterial adherence was dose-dependent and was more extensive in the ileum than in the colon. This study demonstrated that there are remarkable differences between culture conditions that promote adherence of an EHEC O157:H7 strain in vitro and in vivo, that culture conditions profoundly affect adherence to epithelial cells in vitro and in vivo, and that pig ileal loops are better suited to adherence studies than are colon loops. PMID:21731177

Uncovering the dual role of RHAMM as an HA receptor and a regulator of CD44 expression in RHAMM-expressing mesenchymal progenitor cells.

PubMed

Veiseh, Mandana; Leith, Sean J; Tolg, Cornelia; Elhayek, Sallie S; Bahrami, S Bahram; Collis, Lisa; Hamilton, Sara; McCarthy, James B; Bissell, Mina J; Turley, Eva

2015-01-01

The interaction of hyaluronan (HA) with mesenchymal progenitor cells impacts trafficking and fate after tissue colonization during wound repair and these events contribute to diseases such as cancer. How this interaction occurs is poorly understood. Using 10T½ cells as a mesenchymal progenitor model and fluorescent (F-HA) or gold-labeled HA (G-HA) polymers, we studied the role of two HA receptors, RHAMM and CD44, in HA binding and uptake in non-adherent and adherent mesenchymal progenitor (10T½) cells to mimic aspects of cell trafficking and tissue colonization. We show that fluorescent labeled HA (F-HA) binding/uptake was high in non-adherent cells but dropped over time as cells became increasingly adherent. Non-adherent cells displayed both CD44 and RHAMM but only function-blocking anti-RHAMM and not anti-CD44 antibodies significantly reduced F-HA binding/uptake. Adherent cells, which also expressed CD44 and RHAMM, primarily utilized CD44 to bind to F-HA since anti-CD44 but not anti-RHAMM antibodies blocked F-HA uptake. RHAMM overexpression in adherent 10T½ cells led to increased F-HA uptake but this increased binding remained CD44 dependent. Further studies showed that RHAMM-transfection increased CD44 mRNA and protein expression while blocking RHAMM function reduced expression. Collectively, these results suggest that cellular microenvironments in which these receptors function as HA binding proteins differ significantly, and that RHAMM plays at least two roles in F-HA binding by acting as an HA receptor in non-attached cells and by regulating CD44 expression and display in attached cells. Our findings demonstrate adhesion-dependent mechanisms governing HA binding/ uptake that may impact development of new mesenchymal cell-based therapies.

Uncovering the dual role of RHAMM as an HA receptor and a regulator of CD44 expression in RHAMM-expressing mesenchymal progenitor cells

PubMed Central

Veiseh, Mandana; Leith, Sean J.; Tolg, Cornelia; Elhayek, Sallie S.; Bahrami, S. Bahram; Collis, Lisa; Hamilton, Sara; McCarthy, James B.; Bissell, Mina J.; Turley, Eva

2015-01-01

The interaction of hyaluronan (HA) with mesenchymal progenitor cells impacts trafficking and fate after tissue colonization during wound repair and these events contribute to diseases such as cancer. How this interaction occurs is poorly understood. Using 10T½ cells as a mesenchymal progenitor model and fluorescent (F-HA) or gold-labeled HA (G-HA) polymers, we studied the role of two HA receptors, RHAMM and CD44, in HA binding and uptake in non-adherent and adherent mesenchymal progenitor (10T½) cells to mimic aspects of cell trafficking and tissue colonization. We show that fluorescent labeled HA (F-HA) binding/uptake was high in non-adherent cells but dropped over time as cells became increasingly adherent. Non-adherent cells displayed both CD44 and RHAMM but only function-blocking anti-RHAMM and not anti-CD44 antibodies significantly reduced F-HA binding/uptake. Adherent cells, which also expressed CD44 and RHAMM, primarily utilized CD44 to bind to F-HA since anti-CD44 but not anti-RHAMM antibodies blocked F-HA uptake. RHAMM overexpression in adherent 10T½ cells led to increased F-HA uptake but this increased binding remained CD44 dependent. Further studies showed that RHAMM-transfection increased CD44 mRNA and protein expression while blocking RHAMM function reduced expression. Collectively, these results suggest that cellular microenvironments in which these receptors function as HA binding proteins differ significantly, and that RHAMM plays at least two roles in F-HA binding by acting as an HA receptor in non-attached cells and by regulating CD44 expression and display in attached cells. Our findings demonstrate adhesion-dependent mechanisms governing HA binding/ uptake that may impact development of new mesenchymal cell-based therapies. PMID:26528478

Digital holographic microscopy for toxicity testing and cell culture quality control

NASA Astrophysics Data System (ADS)

Kemper, Björn

2018-02-01

For the example of digital holographic microscopy (DHM), it is illustrated how label-free biophysical parameter sets can be extracted from quantitative phase images of adherent and suspended cells, and how the retrieved data can be applied for in-vitro toxicity testing and cell culture quality assessment. This includes results from the quantification of the reactions of cells to toxic substances as well as data from sophisticated monitoring of cell alterations that are related to changes of cell culture conditions.

Adherence of Non-O157 Shiga Toxin–Producing Escherichia coli to Bovine Recto-anal Junction Squamous Epithelial Cells Appears to Be Mediated by Mechanisms Distinct from Those Used by O157

PubMed Central

Hovde, Carolyn J.; John, Manohar

2013-01-01

Abstract This study presents evidence that the pattern (diffuse or aggregative) of adherence of clinically relevant non-O157 Shiga toxin–producing Escherichia coli (STEC) to bovine recto-anal junction squamous epithelial cells is similar to that of E. coli O157, although the mechanisms of adherence appear to be distinct. Our results further suggest that novel adhesins, and not Intimin, are likely involved in non-O157 STEC adherence to bovine recto-anal junction squamous epithelial cells. These findings have important implications for the development of efficacious modalities for blocking adherence of non-O157 STEC to bovine gastrointestinal epithelial cells. PMID:23510495

Increased adherence of sickled and phosphatidylserine-enriched human erythrocytes to cultured human peripheral blood monocytes.

PubMed

Schwartz, R S; Tanaka, Y; Fidler, I J; Chiu, D T; Lubin, B; Schroit, A J

1985-06-01

The precise mechanism by which sickle erythrocytes (RBC) are removed from the circulation is controversial, although it is possible that enhanced recognition of these cells by circulating mononuclear phagocytes could contribute to this process. We investigated this possibility by interacting sickle cells with cultured human peripheral blood monocytes. Our results show that both irreversibly sickled cells (ISC) and deoxygenated reversibly sickled cells (RSC) had a higher avidity for adherence to monocytes than did oxygenated sickle and normal RBC. ISC were the most adherent cell type. Adherence of RSC to monocytes was found to be reversible; reoxygenation of deoxygenated RSC resulted in a significant decrease in RSC--monocyte adherence. Concomitant with alterations in sickle RBC adherence were alterations in the organization and bilayer distribution of membrane phospholipids in these cells. Specifically, enhanced adherence was associated with increased exposure of RBC membrane outer leaflet phosphatidylserine (PS) and phosphatidylethanolamine, whereas lack of adherence was associated with normal patterns of membrane phospholipid distribution. To investigate the possibility of whether the exposure of PS in the outer membrane leaflet of these cells might be responsible for their recognition by monocytes, the membranes of normal RBC were enriched with the fluorescent PS analogue 1-acyl-2[(N-4-nitro-benzo-2-oxa-1,3-diazole)aminocaproyl]-phosphatidy lse rine (NBD-PS) via transfer of the exogenous lipid from a population of donor phospholipid vesicles (liposomes). RBC enriched with NBD-PS exhibited enhanced adherence to monocytes, whereas adherence of RBC enriched with similar amounts of NBD-phosphatidylcholine (NBD-PC) was not increased. Furthermore, preincubation of monocytes with PS liposomes resulted in a approximately 60% inhibition of ISC adherence to monocytes, whereas no inhibition occurred when monocytes were preincubated with PC liposomes. These findings strongly suggest that erythrocyte surface PS may be a ligand recognized by receptors on human peripheral blood monocytes and that abnormal exposure of PS in the outer leaflet of the RBC membrane, as found in sickle RBC, might serve to trigger their recognition by circulating monocytes. Our results further suggest that abnormalities in the organization of erythrocyte membrane phospholipids may have significant pathophysiologic implications, possibly including shortened cell survival.

Effects of mobile phone WeChat services improve adherence to corticosteroid nasal spray treatment for chronic rhinosinusitis after functional endoscopic sinus surgery: a 3-month follow-up study.

PubMed

Feng, Shaoyan; Liang, Zibin; Zhang, Rongkai; Liao, Wei; Chen, Yuan; Fan, Yunping; Li, Huabin

2017-03-01

The objective of the study is to investigate the impact of receiving daily WeChat services on one's cell phone on adherence to corticosteroid nasal spray treatment in chronic rhinosinusitis (CRS) patients after functional endoscopic sinus surgery (FESS). This study was a two-arm, randomized, follow-up investigation. Patients with chronic rhinosinusitis with/without nasal polyps following bilateral FESS were randomised to receive, or to not receive, daily WeChat service on their cell phone to take corticosteroid nasal spray treatment. A prescription of budesonide aqueous nasal spray 128 µg bid was given to all the subjects. Then they returned to the clinic after 30, 60, 90 days. The primary study outcome was adherence to nasal spray treatment, whereas secondary outcomes were change in endoscopic findings and SinoNasal Outcome Test-20 (SNOT-20). On the whole, there was a significant inter-group difference in the change of adherence rate (F = 90.88, p = 0.000). The WeChat group had much higher adherence rate than the control group during the follow-up. In terms of postoperative endoscopic scores and SNOT-20, except granulation score, no significant differences were observed between the two randomization groups. WeChat services are already after a short period of observation associated with improved adherence to corticosteroid nasal spray treatment in CRS patients after FESS.

Single cell dual adherent-suspension co-culture micro-environment for studying tumor-stromal interactions with functionally selected cancer stem-like cells.

PubMed

Chen, Yu-Chih; Zhang, Zhixiong; Fouladdel, Shamileh; Deol, Yadwinder; Ingram, Patrick N; McDermott, Sean P; Azizi, Ebrahim; Wicha, Max S; Yoon, Euisik

2016-08-07

Considerable evidence suggests that cancer stem-like cells (CSCs) are critical in tumor pathogenesis, but their rarity and transience has led to much controversy about their exact nature. Although CSCs can be functionally identified using dish-based tumorsphere assays, it is difficult to handle and monitor single cells in dish-based approaches; single cell-based microfluidic approaches offer better control and reliable single cell derived sphere formation. However, like normal stem cells, CSCs are heavily regulated by their microenvironment, requiring tumor-stromal interactions for tumorigenic and proliferative behaviors. To enable single cell derived tumorsphere formation within a stromal microenvironment, we present a dual adherent/suspension co-culture device, which combines a suspension environment for single-cell tumorsphere assays and an adherent environment for co-culturing stromal cells in close proximity by selectively patterning polyHEMA in indented microwells. By minimizing dead volume and improving cell capture efficiency, the presented platform allows for the use of small numbers of cells (<100 cells). As a proof of concept, we co-cultured single T47D (breast cancer) cells and primary cancer associated fibroblasts (CAF) on-chip for 14 days to monitor sphere formation and growth. Compared to mono-culture, co-cultured T47D have higher tumorigenic potential (sphere formation rate) and proliferation rates (larger sphere size). Furthermore, 96-multiplexed single-cell transcriptome analyses were performed to compare the gene expression of co-cultured and mono-cultured T47D cells. Phenotypic changes observed in co-culture correlated with expression changes in genes associated with proliferation, apoptotic suppression, tumorigenicity and even epithelial-to-mesechymal transition. Combining the presented platform with single cell transcriptome analysis, we successfully identified functional CSCs and investigated the phenotypic and transcriptome effects induced by tumor-stromal interactions.

Clonogenic assay: adherent cells.

PubMed

Rafehi, Haloom; Orlowski, Christian; Georgiadis, George T; Ververis, Katherine; El-Osta, Assam; Karagiannis, Tom C

2011-03-13

The clonogenic (or colony forming) assay has been established for more than 50 years; the original paper describing the technique was published in 1956. Apart from documenting the method, the initial landmark study generated the first radiation-dose response curve for X-ray irradiated mammalian (HeLa) cells in culture. Basically, the clonogenic assay enables an assessment of the differences in reproductive viability (capacity of cells to produce progeny; i.e. a single cell to form a colony of 50 or more cells) between control untreated cells and cells that have undergone various treatments such as exposure to ionising radiation, various chemical compounds (e.g. cytotoxic agents) or in other cases genetic manipulation. The assay has become the most widely accepted technique in radiation biology and has been widely used for evaluating the radiation sensitivity of different cell lines. Further, the clonogenic assay is commonly used for monitoring the efficacy of radiation modifying compounds and for determining the effects of cytotoxic agents and other anti-cancer therapeutics on colony forming ability, in different cell lines. A typical clonogenic survival experiment using adherent cells lines involves three distinct components, 1) treatment of the cell monolayer in tissue culture flasks, 2) preparation of single cell suspensions and plating an appropriate number of cells in petri dishes and 3) fixing and staining colonies following a relevant incubation period, which could range from 1-3 weeks, depending on the cell line. Here we demonstrate the general procedure for performing the clonogenic assay with adherent cell lines with the use of an immortalized human keratinocyte cell line (FEP-1811). Also, our aims are to describe common features of clonogenic assays including calculation of the plating efficiency and survival fractions after exposure of cells to radiation, and to exemplify modification of radiation-response with the use of a natural antioxidant formulation.

Improved assay for quantitating adherence of ruminal bacteria to cellulose.

PubMed Central

Rasmussen, M A; White, B A; Hespell, R B

1989-01-01

A quantitative technique suitable for the determination of adherence of ruminal bacteria to cellulose was developed. This technique employs adherence of cells to cellulose disks and alleviates the problem of nonspecific cell entrapment within cellulose particles. By using this technique, it was demonstrated that the adherence of Ruminococcus flavefaciens FD1 to cellulose was inhibited by formaldehyde, methylcellulose, and carboxymethyl cellulose. Adherence was unaffected by acid hydrolysates of methylcellulose, glucose, and cellobiose. PMID:2782879

Patterns of Adherence of Helicobacter pylori Clinical Isolates to Epithelial Cells, and its Association with Disease and with Virulence Factors.

PubMed

Vázquez-Jiménez, Flor Elizabeth; Torres, Javier; Flores-Luna, Lourdes; Cerezo, Silvia Giono; Camorlinga-Ponce, Margarita

2016-02-01

Adherence to the gastric epithelium is one of the most important steps of Helicobacter pylori to remain and cause disease. The aim of this study was to analyze whether H. pylori isolates from patients with different gastroduodenal diseases present differences in the pattern of adherence to gastric epithelial cells (AGS), in the ability to induce IL-8, and in the presence of virulence genes. We tested 75 H. pylori strains isolated from nonatrophic gastritis, gastric cancer, and duodenal ulcer patients. The adhesion pattern and IL-8 induction were determined in AGS cells, and invasion of AGS cells was studied using a gentamicin protection assay. The IL-8 levels induced were determined by ELISA. Helicobacter pylori strains presented diffuse adherence (DA) and localized (LA) adherence patterns, similar to those described for enteropathogenic E. coli (EPEC), were observed in AGS cells. A DA pattern was observed in 57% and LA in 43% of the strains, and DA was more frequent in isolates from patients with gastric cancer (p = 0.044). Strains with a LA pattern induced higher levels of IL-8 (p = 0.042) in AGS cells. The adherence pattern was not associated with neither invasiveness nor with the presence of virulence genes. Our study shows that H. pylori strains present adherence patterns to AGS cells resembling those observed in EPEC and that these patterns may be associated with disease and with activity on AGS cells. © 2015 John Wiley & Sons Ltd.

Corynebacterium diphtheriae employs specific minor pilins to target human pharyngeal epithelial cells

PubMed Central

Mandlik, Anjali; Swierczynski, Arlene; Das, Asis; Ton-That, Hung

2010-01-01

Summary Adherence to host tissues mediated by pili is pivotal in the establishment of infection by many bacterial pathogens. Corynebacterium diphtheriae assembles on its surface three distinct pilus structures. The function and the mechanism of how various pili mediate adherence, however, have remained poorly understood. Here we show that the SpaA-type pilus is sufficient for the specific adherence of corynebacteria to human pharyngeal epithelial cells. The deletion of the spaA gene, which encodes the major pilin forming the pilus shaft, abolishes pilus assembly but not adherence to pharyngeal cells. In contrast, adherence is greatly diminished when either minor pilin SpaB or SpaC is absent. Antibodies directed against either SpaB or SpaC block bacterial adherence. Consistent with a direct role of the minor pilins, latex beads coated with SpaB or SpaC protein bind specifically to pharyngeal cells. Therefore, tissue tropism of corynebacteria for pharyngeal cells is governed by specific minor pilins. Importantly, immunoelectron microscopy and immunofluorescence studies reveal clusters of minor pilins that are anchored to cell surface in the absence of a pilus shaft. Thus, the minor pilins may also be cell wall anchored in addition to their incorporation into pilus structures that could facilitate tight binding to host cells during bacterial infection. PMID:17376076

In vitro adherence patterns of Shigella serogroups to bovine recto-anal junction squamous epithelial (RSE) cells are similar to those of Escherichia coli O157

USDA-ARS?s Scientific Manuscript database

The aim of this study was to determine whether Shigella species, which are human gastrointestinal pathogens, can adhere to cattle recto-anal junction squamous epithelial (RSE) cells using a recently standardized adherence assay, and to compare their adherence patterns to that of Escherichia coli O15...

Chromosomal Expression of the Haemophilus influenzae Hap Autotransporter Allows Fine-Tuned Regulation of Adhesive Potential via Inhibition of Intermolecular Autoproteolysis

PubMed Central

Fink, Doran L.; St. Geme III, Joseph W.

2003-01-01

The Haemophilus influenzae Hap autotransporter is a nonpilus adhesin that promotes adherence to respiratory epithelial cells and selected extracellular matrix proteins and facilitates bacterial aggregation and microcolony formation. Hap consists of a 45-kDa outer membrane translocator domain called Hapβ and a 110-kDa extracellular passenger domain called HapS. All adhesive activity resides within HapS, which also contains protease activity and directs its own secretion from the bacterial cell surface via intermolecular autoproteolysis. In the present study, we sought to determine the relationship between the magnitude of Hap expression, the efficiency of Hap autoproteolysis, and the level of Hap-mediated adherence and aggregation. We found that a minimum threshold of Hap precursor was required for autoproteolysis and that this threshold approximated expression of Hap from a chromosomal allele, as occurs in H. influenzae clinical isolates. Chromosomal expression of wild-type Hap was sufficient to promote significant adherence to epithelial cells and extracellular matrix proteins, and adherence was enhanced substantially by inhibition of autoproteolysis. In contrast, chromosomal expression of Hap was sufficient to promote bacterial aggregation only when autoproteolysis was inhibited, indicating that the threshold for Hap-mediated aggregation is above the threshold for autoproteolysis. These results highlight the critical role of autoproteolysis and an intermolecular mechanism of cleavage in controlling the diverse adhesive activities of Hap. PMID:12591878

Automated single cell microbioreactor for monitoring intracellular dynamics and cell growth in free solution†

PubMed Central

Johnson-Chavarria, Eric M.; Agrawal, Utsav; Tanyeri, Melikhan; Kuhlman, Thomas E.

2014-01-01

We report an automated microfluidic-based platform for single cell analysis that allows for cell culture in free solution with the ability to control the cell growth environment. Using this approach, cells are confined by the sole action of gentle fluid flow, thereby enabling non-perturbative analysis of cell growth away from solid boundaries. In addition, the single cell microbioreactor allows for precise and time-dependent control over cell culture media, with the combined ability to observe the dynamics of non-adherent cells over long time scales. As a proof-of-principle demonstration, we used the platform to observe dynamic cell growth, gene expression, and intracellular diffusion of repressor proteins while precisely tuning the cell growth environment. Overall, this microfluidic approach enables the direct observation of cellular dynamics with exquisite control over environmental conditions, which will be useful for quantifying the behaviour of single cells in well-defined media. PMID:24836754

Biocompatibility of orthodontic bands following exposure to dental plaque.

PubMed

Hornikel, Sandra; Erbe, Christina; Schmidtmann, Irene; Wehrbein, Heiner

2011-03-01

The aim of this study was to assess the biocompatibility of orthodontic bands following exposure to the human oral environment. Cell adherence and cell morphology of gingival fibroblasts grown on 32 orthodontic bands were tested. The bands were in place intraorally for 6 to 37 months. We observed cell adherence in 76% of the previously plaque-free surfaces. Cell morphology was 50% spherical and 50% elongated. The surfaces that had had plaque attached demonstrated cell adherence in 84% of the given areas; those cells were spherical in 42% and elongated in 58%. We conclude that individual oral hygiene habits during orthodontic treatment seem to have no effect on the biocompatibility of orthodontic bands, as we failed to discern a difference in either cell adherence or cell morphology in areas with and without prior plaque attachment.

The Role of Ionic Interactions in the Adherence of the S. epidermidis Adhesin SdrF to Prosthetic Material

PubMed Central

Toba, Faustino A.; Visai, Livia; Trivedi, Sheetal; Lowy, Franklin D.

2012-01-01

Staphylococcus epidermidis infections are common complications of prosthetic device implantation. SdrF, a surface protein, appears to play a critical role in the initial colonization step by adhering to type I collagen and Dacron™. The role of ionic interactions in S. epidermidis adherence to prosthetic material was examined. SdrF was cloned and expressed in Lactococcus lactis. The effect of pH, cation concentration and detergents on adherence to different types of plastic surfaces was assessed by crystal violet staining and bacterial cell counting. SdrF, in contrast with controls and other S. epidermidis surface proteins, bound to hydrophobic materials such as polystyrene. Binding was an ionic interaction and was affected by surface charge of the plastic, pH and cation concentration. Adherence of the SdrF construct was increased to positively charged plastics and was reduced by increasing concentrations of Ca2+ and Na+. Binding was optimal at pH 7.4. Kinetic studies demonstrated that the SdrF B domain, as well as one of the B subdomains was sufficient to mediate binding. The SdrF construct also bound more avidly to Goretex™ than the lacotococcal control. SdrF is a multifunctional protein that contributes to prosthetic devices infections by ionic, as well as specific receptor-ligand interactions. PMID:23039791

Adherence to human lung microvascular endothelial cells (HMVEC-L) of Plasmodium vivax isolates from Colombia

PubMed Central

2013-01-01

Background For years Plasmodium vivax has been considered the cause of benign malaria. Nevertheless, it has been observed that this parasite can produce a severe disease comparable to Plasmodium falciparum. It has been suggested that some physiopathogenic processes might be shared by these two species, such as cytoadherence. Recently, it has been demonstrated that P. vivax-infected erythrocytes (Pv-iEs) have the capacity to adhere to endothelial cells, in which intercellular adhesion molecule-1 (ICAM-1) seems to be involved in this process. Methods Adherence capacity of 21 Colombian isolates, from patients with P. vivax mono-infection to a microvascular line of human lung endothelium (HMVEC-L) was assessed in static conditions and binding was evaluated at basal levels or in tumor necrosis factor (TNF) stimulated cells. The adherence specificity for the ICAM-1 receptor was determined through inhibition with an anti-CD54 monoclonal antibody. Results The majority of P. vivax isolates, 13 out of 21 (61.9%), adhered to the HMVEC-L cells, but P. vivax adherence was at least seven times lower when compared to the four P. falciparum isolates. Moreover, HMVEC-L stimulation with TNF led to an increase of 1.6-fold in P. vivax cytoadhesion, similar to P. falciparum isolates (1.8-fold) at comparable conditions. Also, blockage of ICAM-1 receptor with specific antibodies showed a significant 50% adherence reduction. Conclusions Plasmodium vivax isolates found in Colombia are also capable of adhering specifically in vitro to lung endothelial cells, via ICAM-1 cell receptor, both at basal state and after cell stimulation with TNF. Collectively, these findings reinforce the concept of cytoadherence for P. vivax, but here, to a different endothelial cell line and using geographical distinct isolates, thus contributing to understanding P. vivax biology. PMID:24080027

Muscle-derived stem cells isolated as non-adherent population give rise to cardiac, skeletal muscle and neural lineages.

PubMed

Arsic, Nikola; Mamaeva, Daria; Lamb, Ned J; Fernandez, Anne

2008-04-01

Stem cells with the ability to differentiate in specialized cell types can be extracted from a wide array of adult tissues including skeletal muscle. Here we have analyzed a population of cells isolated from skeletal muscle on the basis of their poor adherence on uncoated or collagen-coated dishes that show multi-lineage differentiation in vitro. When analysed under proliferative conditions, these cells express stem cell surface markers Sca-1 (65%) and Bcrp-1 (80%) but also MyoD (15%), Neuronal beta III-tubulin (25%), GFAP (30%) or Nkx2.5 (1%). Although capable of growing as non-attached spheres for months, when given an appropriate matrix, these cells adhere giving rise to skeletal muscle, neuronal and cardiac muscle cell lineages. A similar cell population could not be isolated from either bone marrow or cardiac tissue suggesting their specificity to skeletal muscle. When injected into damaged muscle, these non-adherent muscle-derived cells are retrieved expressing Pax7, in a sublaminar position characterizing satellite cells and participate in forming new myofibers. These data show that a non-adherent stem cell population can be specifically isolated and expanded from skeletal muscle and upon attachment to a matrix spontaneously differentiate into muscle, cardiac and neuronal lineages in vitro. Although competing with resident satellite cells, these cells are shown to significantly contribute to repair of injured muscle in vivo supporting that a similar muscle-derived non-adherent cell population from human muscle may be useful in treatment of neuromuscular disorders.

Soft electroporation for delivering molecules into tightly adherent mammalian cells through 3D hollow nanoelectrodes.

PubMed

Caprettini, Valeria; Cerea, Andrea; Melle, Giovanni; Lovato, Laura; Capozza, Rosario; Huang, Jian-An; Tantussi, Francesco; Dipalo, Michele; De Angelis, Francesco

2017-08-17

Electroporation of in-vitro cultured cells is widely used in biological and medical areas to deliver molecules of interest inside cells. Since very high electric fields are required to electroporate the plasma membrane, depending on the geometry of the electrodes the required voltages can be very high and often critical to cell viability. Furthermore, in traditional electroporation configuration based on planar electrodes there is no a priori certain feedback about which cell has been targeted and delivered and the addition of fluorophores may be needed to gain this information. In this study we present a nanofabricated platform able to perform intracellular delivery of membrane-impermeable molecules by opening transient nanopores into the lipid membrane of adherent cells with high spatial precision and with the application of low voltages (1.5-2 V). This result is obtained by exploiting the tight seal that the cells present with 3D fluidic hollow gold-coated nanostructures that act as nanochannels and nanoelectrodes at the same time. The final soft-electroporation platform provides an accessible approach for controlled and selective drug delivery on ordered arrangements of cells.

Cellular requirements for cutaneous sensitivity elicitation.

PubMed

Aoki, I

1985-01-01

The role of glass-adherent cells in cutaneous sensitivity (CS) elicitation has been analyzed in this study. CS responses have been revealed to be mediated by at least two distinct subsets of genetically restricted T cells: I-restricted 'DTH-like' T cells and K/D-restricted 'CTL-like' T cells. Both T-cell responses require I-A-positive glass-adherent cell populations, which lack T-cell markers, to manifest their activities. The role of the adherent cells is different in the 'DTH-like' responses and the 'CTL-like' responses. The disparities between the present results and previous contentions are discussed in this paper.

Ion channels involved in cell volume regulation: effects on migration, proliferation, and programmed cell death in non adherent EAT cells and adherent ELA cells.

PubMed

Hoffmann, Else Kay

2011-01-01

This mini review outlines studies of cell volume regulation in two closely related mammalian cell lines: nonadherent Ehrlich ascites tumour cells (EATC) and adherent Ehrlich Lettre ascites (ELA) cells. Focus is on the regulatory volume decrease (RVD) that occurs after cell swelling, the volume regulatory ion channels involved, and the mechanisms (cellular signalling pathways) that regulate these channels. Finally, I shall also briefly review current investigations in these two cell lines that focuses on how changes in cell volume can regulate cell functions such as cell migration, proliferation, and programmed cell death. Copyright © 2011 S. Karger AG, Basel.

Transient maintenance in bioreactor improves health of neuronal cells.

PubMed

Di Loreto, Silvia; Sebastiani, Pierluigi; Benedetti, Elisabetta; Zimmitti, Vincenzo; Caracciolo, Valentina; Amicarelli, Fernanda; Cimini, Annamaria; Adorno, Domenico

2006-01-01

To examine whether a neuronal cell suspension can be held in vitro for a relatively short period without compromising survival rates and functionality, we have set up an experimental protocol planning 24 h of suspension culture in a rotary wall vessel (RWV) bioreactor before plating in a conventional adherent system. Apoptosis measurement and activated caspase-8, -9, and -3 detection have demonstrated that survey of the cells was not affected. The activity of major antioxidant enzymes (AOE), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT), was significantly decreased in RWV-maintained cells. A significant decrease of tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) is coupled with a level of activated nuclear factor-kappaB (NF-kappaB) protein significantly lower in RVW cells than in the control. On the contrary, the level of IL-6 expression did not change between the test and the control. A significant up-regulation of growth-associated protein-43 (GAP-43), peroxisome proliferator-activated receptor-beta/delta (PPARbeta/delta), and acyl-CoA synthetase 2 (ACS2) in RWV cells has been detected. We provide the evidence that primary neuronal cells, at an early stage of development, can be maintained in a suspension condition before adherent plating. This experimental environment does not induce detrimental effects but may have an activator role, leading cells to development and maturation in a tridimensional state.

Adherence and virulence genes of Escherichia coli from children diarrhoea in the Brazilian Amazon.

PubMed

Benevides-Matos, Najla; Pieri, Fabio A; Penatti, Marilene; Orlandi, Patrícia P

2015-03-01

The bacterial pathogen most commonly associated with endemic forms of childhood diarrhoea is Escherichia coli . Studies of epidemiological characteristics of HEp-2 cell-adherent E. coli in diarrhoeal disease are required, particularly in developing countries. The aim of this study was evaluate the presence and significance of adherent Escherichia coli from diarrhoeal disease in children. The prevalence of LA, AA, and DA adherence patterns were determined in HEp-2 cells, the presence of virulence genes and the presence of the O serogroups in samples obtained from 470 children with acute diarrhoea and 407 controls in Porto Velho, Rondônia, Brazil. E. coli isolates were identified by PCR specific for groups of adherent E. coli . Out of 1,156 isolates obtained, 128 (11.0%) were positive for eae genes corresponding to EPEC, however only 38 (29.6%) of these amplified bfpA gene . EAEC were isolated from 164 (14.1%) samples; of those 41(25%), 32 (19%) and 16 (9.7%) amplified eagg , aggA or aafA genes, respectively and aggA was significantly associated with diarrhoea ( P = 0.00006). DAEC identified by their adhesion pattern and there were few isolates. In conclusion, EAEC was the main cause of diarrhoea in children, especially when the aggA gene was present, followed by EPEC and with a negligible presence of DAEC.

In vitro model for Campylobacter pylori adherence properties.

PubMed Central

Neman-Simha, V; Mégraud, F

1988-01-01

The adherence of 12 strains of Campylobacter pylori was studied on four cell lines. Immunofluorescence and scanning and transmission electron microscopy were used to visualize the bacteria. A heavy adherence to the epithelial cell line HEp-2 and to the intestinal cell line Int-407 was noted. By transmission electron microscopy, a close association between bacteria and cells in the form of cup-like structures was observed, but pedestals were not present. Images PMID:3182085

Adherence of Clostridium perfringens spores to human intestinal epithelial Caco-2 cells.

PubMed

Sakanoue, Hideyo; Nakano, Takashi; Sano, Kouichi; Yasugi, Mayo; Monma, Chie; Miyake, Masami

2018-03-01

Clostridium perfringens is a gram-positive, spore-forming bacillus, and is a causative agent of foodborne infection, antibiotic-associated diarrhoea and sporadic diarrhoea in humans. In cases of antibiotic-associated and sporadic diarrhoea, C. perfringens colonises the intestine, proliferates and causes disease. However, bacterial colonisation of the intestine is not considered necessary in the pathogenesis of foodborne illness, because such pathogenesis can be explained by anchorage-independent production of diarrhoeic toxin by the bacterium in the intestine. In this study, we used an in vitro adherence assay to examine the adherence of C. perfringens spores to human intestinal Caco-2 cells. Adherence of spores from isolates of foodborne illness and nosocomial infection was observed within 15 min, and plateaued 60 min after inoculation. Electron microscopy revealed a tight association of spores with the surface of Caco-2 cells. The adherence of vegetative cells could not be confirmed by the same method, however. These results suggest that C. perfringens spores may adhere to intestinal epithelial cells in vivo, although its biological significance remains to be determined.

Neuron-Glia Adhesion is Inhibited by Antibodies to Neural Determinants

NASA Astrophysics Data System (ADS)

Grumet, M.; Rutishauser, U.; Edelman, G. M.

1983-10-01

Suspensions of embryonic chick neuronal cells adhered to monolayers of glial cells, but few neurons bound to control monolayers of fibroblastic cells from meninges or skin. Neuronal cell-glial cell adhesion was inhibited by prior incubation of the neurons with Fab' fragments of antibodies to neuronal membranes. In contrast, antibodies to the neural cell adhesion molecule (N-CAM) did not inhibit the binding. These results suggest that a specific adhesive mechanism between neurons and glial cells exists and that it is mediated by CAM's that differ from those so far identified.

Microfabrication of proangiogenic cell-laden alginate-g-pyrrole hydrogels.

PubMed

DeVolder, Ross J; Zill, Andrew T; Jeong, Jae H; Kong, Hyunjoon

2012-11-01

Cells have been extensively studied for their uses in various therapies because of their capacities to produce therapeutic proteins and recreate new tissues. It has often been suggested that the efficacy of cell therapies can greatly be improved through the ability to localize and regulate cellular activities at a transplantation site; however, the technologies for this control are lacking. Therefore, this study reports a cell-Laden hydrogel patch engineered to support the proliferation and angiogenic growth factor expression of cells adhered to their surfaces, and to further promote neovascularization. Hydrogels consisting of alginate chemically linked with pyrrole units, termed alginate-g-pyrrole, were prepared through an oxidative cross-linking reaction between pyrrole units. Fibroblasts adhered to the alginate-g-pyrrole hydrogels, and exhibited increased proliferation and overall vascular endothelial growth factor (VEGF) expression, compared to those on pyrrole-free hydrogels. Furthermore, the alginate-g-pyrrole hydrogel surfaces were modified to present microposts, subsequently increasing the amount of pyrrole units on their surfaces. Cells adhered to the microfabricated gel surfaces exhibited increased proliferation and overall VEGF expression proportional to the density of the microposts. The resulting micropatterned alginate-g-pyrrole hydrogels exhibited increases in the size and density of mature blood vessels when implanted on chick chorioallantoic membranes (CAMs). The hydrogel system developed in this study will be broadly useful for improving the efficacy of a wide array of cell-based wound healing and tissue regenerative therapies. Copyright © 2012 Elsevier Ltd. All rights reserved.

Abuse and Resilience in Relation to HAART Medication Adherence and HIV Viral Load Among Women with HIV in the United States

PubMed Central

Cohen, Mardge; Weber, Kathleen; Cruise, Ruth; Kelso, Gwendolyn

2014-01-01

Abstract Abuse is highly prevalent among HIV+ women, leading to behaviors, including lower adherence to highly active antiretroviral therapy (HAART) that result in poor health outcomes. Resilience (functioning competently despite adversity) may buffer the negative effects of abuse. This study investigated how resilience interacted with abuse history in relation to HAART adherence, HIV viral load (VL), and CD4+ cell count among a convenience sample of 138 HIV+ women from the Ruth M. Rothstein CORE Center/Cook County Health and Hospital Systems site of the Women's Interagency HIV Study (WIHS). Resilience was measured by the 10-item Connor-Davidson Resilience Scale (CD-RISC). HAART adherence (≥95% vs. <95% self reported usage of prescribed medication) and current or prior sexual, physical, or emotional/domestic abuse, were reported during structured interviews. HIV viral load (≥20 vs. <20 copies/mL) and CD4+ count (200 vs. <200 cells/mm) were measured with blood specimens. Multiple logistic regressions, controlling for age, race, income, enrollment wave, substance use, and depressive symptoms, indicated that each unit increase in resilience was significantly associated with an increase in the odds of having ≥95% HAART adherence and a decrease in the odds of having a detectable viral load. Resilience-Abuse interactions showed that only among HIV+ women with sexual abuse or multiple abuses did resilience significantly relate to an increase in the odds of ≥95% HAART adherence. Interventions to improve coping strategies that promote resilience among HIV+ women may be beneficial for achieving higher HAART adherence and viral suppression. PMID:24568654

Adherent culture conditions enrich the side population obtained from the cochlear modiolus-derived stem/progenitor cells.

PubMed

Chao, Ting-Ting; Wang, Chih-Hung; Chen, Hsin-Chien; Shih, Cheng-Ping; Sytwu, Huey-Kang; Huang, Kun-Lun; Chen, Shao-Yuan

2013-05-01

Previously, our group reported that sphere-forming cells derived from the organ of Corti represent the stem/progenitor cells (SPCs) of the cochlea due to their properties of self-renewal and multipotency. However, long-term propagation of sphere-forming cells under suspension culture conditions may fail to maintain the characteristic stemness of these cells. Therefore, this study investigated whether an adherent culture system would be beneficial in terms of preserving more stem-like cells for long-term manipulations in vitro. Isolated modiolus-derived SPCs were placed on poly-d-lysine-coated petri dishes to form the so-called "adherent" culture system. Modiolus SPCs cultured under adherent conditions exhibited a significantly increased percentage of cells with the side population (SP) phenotype (18.6%) compared with cells cultured under conventional suspension culture conditions (0.8%). Even after repeated passages, modiolus SPCs cultured under adherent culture conditions preserved more SP phenotype cells. In comparison with the non-SP phenotype cells, the sorted SP cells exhibited more stem-like but less differentiated properties, with an upregulated expression of the ATP-binding cassette subfamily G member 2 (ABCG2), Nestin, Sox2, and Nanog proteins. Furthermore, Retinoic acid (RA) treatment confirmed the expression of the multipotent differentiation markers in the SP cells, including TUJ1, pancytokeratin, glial fibrillary acidic protein (GFAP), and p27(Kip1). Employment of an adherent culture system, instead of a suspension culture system, resulted in the enrichment of the SP cells from SPCs while retaining their stemness and multipotency. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Versican and the regulation of cell phenotype in disease.

PubMed

Wight, Thomas N; Kinsella, Michael G; Evanko, Stephen P; Potter-Perigo, Susan; Merrilees, Mervyn J

2014-08-01

Versican is an extracellular matrix (ECM) proteoglycan that is present in the pericellular environment of most tissues and increases in many different diseases. Versican interacts with cells to influence the ability of cells to proliferate, migrate, adhere and assemble an ECM. The structure of the versican molecule is briefly reviewed and studies highlighting those factors that promote versican synthesis and degradation and their impact on cell phenotype in disease are discussed. Particular attention is given to vascular disease, but other diseases where versican is important are covered as well, most notably different forms of cancers. Attention is given to mechanisms(s) by which versican influences cell behaviors through either direct or indirect processes. Versican produced by either stromal cells or myeloid cells can have a major impact influencing immunity and inflammation. Finally, studies controlling versican accumulation that either delay or inhibit the progression of disease will be highlighted. Versican is one component of the ECM that can influence the ability of cells to proliferate, migrate, adhere, and remodel the ECM. Targeting versican as a way to control cell phenotype offers a novel approach in the treatment of disease. ECM molecules such as versican contribute to the structural integrity of tissues and interact with cells through direct and indirect means to regulate, in part, cellular events that form the basis of disease. This article is part of a Special Issue entitled Matrix-mediated cell behaviour and properties. Copyright © 2014 Elsevier B.V. All rights reserved.

Sensing dynamic cytoplasm refractive index changes of adherent cells with quantitative phase microscopy using incorporated microspheres as optical probes.

PubMed

Przibilla, Sabine; Dartmann, Sebastian; Vollmer, Angelika; Ketelhut, Steffi; Greve, Burkhard; von Bally, Gert; Kemper, Björn

2012-09-01

The intracellular refractive index is an important parameter that describes the optical density of the cytoplasm and the concentration of the intracellular solutes. The refractive index of adherently grown cells is difficult to access. We present a method in which silica microspheres in living cells are used to determine the cytoplasm refractive index with quantitative phase microscopy. The reliability of our approach for refractive index retrieval is shown by data from a comparative study on osmotically stimulated adherent and suspended human pancreatic tumor cells. Results from adherent human fibro sarcoma cells demonstrate the capability of the method for sensing of dynamic refractive index changes and its usage with microfluidics.

Developing a Continuous Bioprocessing Approach to Stromal Cell Manufacture.

PubMed

Miotto, Martina; Gouveia, Ricardo; Abidin, Fadhilah Zainal; Figueiredo, Francisco; Connon, Che J

2017-11-29

To this day, the concept of continuous bioprocessing has been applied mostly to the manufacture of molecular biologics such as proteins, growth factors, and secondary metabolites with biopharmaceutical uses. The present work now sets to explore the potential application of continuous bioprocess methods to source large numbers of human adherent cells with potential therapeutic value. To this purpose, we developed a smart multifunctional surface coating capable of controlling the attachment, proliferation, and subsequent self-detachment of human corneal stromal cells. This system allowed the maintenance of cell cultures under steady-state growth conditions, where self-detaching cells were continuously replenished by the proliferation of those remaining attached. This facilitated a closed, continuous bioprocessing platform with recovery of approximately 1% of the total adherent cells per hour, a yield rate that was maintained for 1 month. Moreover, both attached and self-detached cells were shown to retain their original phenotype. Together, these results represent the proof-of-concept for a new high-throughput, high-standard, and low-cost biomanufacturing strategy with multiple potentials and important downstream applications.

Cyto-adherence of Mycoplasma mycoides subsp. mycoides to bovine lung epithelial cells.

PubMed

Aye, Racheal; Mwirigi, Martin Kiogora; Frey, Joachim; Pilo, Paola; Jores, Joerg; Naessens, Jan

2015-02-07

Mycoplasma mycoides subsp. mycoides (Mmm) is the causative agent of contagious bovine pleuropneumonia (CBPP), a respiratory disease of cattle, whereas the closely related Mycoplasma mycoides subsp. capri (Mmc) is a goat pathogen. Cyto-adherence is a crucial step in host colonization by mycoplasmas and subsequent pathogenesis. The aim of this study was to investigate the interactions between Mmm and mammalian host cells by establishing a cyto-adherence flow cytometric assay and comparing tissue and species specificity of Mmm and Mmc strains. There were little significant differences in the adherence patterns of eight different Mmm strains to adult bovine lung epithelial cells. However, there was statistically significant variation in binding to different host cells types. Highest binding was observed with lung epithelial cells, intermediate binding with endothelial cells and very low binding with fibroblasts, suggesting the presence of effective adherence of Mmm on cells lining the airways of the lung, which is the target organ for this pathogen, possibly by high expression of a specific receptor. However, binding to bovine fetal lung epithelial cells was comparably low; suggesting that the lack of severe pulmonary disease seen in many infected young calves can be explained by reduced expression of a specific receptor. Mmm bound with high efficiency to adult bovine lung cells and less efficiently to calves or goat lung cells. The data show that cyto-adherence of Mmm is species- and tissue- specific confirming its role in colonization of the target host and subsequent infection and development of CBPP.

Phenotypic and Functional Changes in Blood Monocytes Following Adherence to Endothelium

PubMed Central

Tso, Colin; Rye, Kerry-Anne; Barter, Philip

2012-01-01

Objective Blood monocytes are known to express endothelial-like genes during co-culture with endothelium. In this study, the time-dependent change in the phenotype pattern of primary blood monocytes after adhering to endothelium is reported using a novel HLA-A2 mistyped co-culture model. Methods and Results Freshly isolated human PBMCs were co-cultured with human umbilical vein endothelial cells or human coronary arterial endothelial cells of converse human leukocyte antigen A2 (HLA-A2) status. This allows the tracking of the PBMC-derived cells by HLA-A2 expression and assessment of their phenotype pattern over time. PBMCs that adhered to the endothelium at the start of the co-culture were predominantly CD11b+ blood monocytes. After 24 to 72 hours in co-culture, the endothelium-adherent monocytes acquired endothelial-like properties including the expression of endothelial nitric oxide synthase, CD105, CD144 and vascular endothelial growth factor receptor 2. The expression of monocyte/macrophage lineage antigens CD14, CD11b and CD36 were down regulated concomitantly. The adherent monocytes did not express CD115 after 1 day of co-culture. By day 6, the monocyte-derived cells expressed vascular cell adhesion molecule 1 in response to tumour necrosis factor alpha. Up to 10% of the PBMCs adhered to the endothelium. These monocyte-derived cells contributed up to 30% of the co-cultured cell layer and this was dose-dependent on the PBMC seeding density. Conclusions Human blood monocytes undergo rapid phenotype change to resemble endothelial cells after adhering to endothelium. PMID:22615904

Suppression of the PI3K subunit p85α delays embryoid body development and inhibits cell adhesion.

PubMed

Gurney, Susan M R; Forster, Peter; Just, Ursula; Schwanbeck, Ralf

2011-12-01

Phosphatidylinositol-3-kinases (PI3Ks) exert a variety of signaling functions in eukaryotes. We suppressed the PI3K regulatory subunit p85α using a small interfering RNA (Pik3r1 siRNA) and examined the effects on embryoid body (EB) development in hanging drop culture. We observed a 150% increase in the volume of the treated EBs within 24 h, compared to the negative controls. Fluorescence Activated Cell Sorting (FACS) assays showed that this increase in volume is not due to increased cellular proliferation. Instead, the increase in volume appears to be due to reduced cellular aggregation and adherence. This is further shown by our observation that 40% of treated EBs form twin instead of single EBs, and that they have a significantly reduced ability to adhere to culture dishes when plated. A time course over the first 96 h reveals that the impaired adherence is transient and explained by an initial 12-hour delay in EB development. Quantitative PCR expression analysis suggests that the adhesion molecule integrin-β1 (ITGB1) is transiently downregulated by the p85α suppression. In conclusion we found that suppressing p85α leads to a delay in forming compact EBs, accompanied by a transient inability of the EBs to undergo normal cell-cell and cell-substrate adhesion. Copyright © 2011 Wiley Periodicals, Inc.

In vitro assessment of stainless steel orthodontic brackets coated with titanium oxide mixed Ag for anti-adherent and antibacterial properties against Streptococcus mutans and Porphyromonas gingivalis.

PubMed

Fatani, Eman Jameel; Almutairi, Hamed H; Alharbi, Ali O; Alnakhli, Yasser Obaidallah; Divakar, Darshan Devang; Muzaheed; Alkheraif, Abdulaziz Abdullah; Khan, Aftab Ahmed

2017-11-01

Orthodontic brackets made from stainless steel were introduced in dentistry, though they have less ability in reducing enamel demineralization and are not successful in preventing microbial as well as biofilm growth. In this study, we evaluated the significant role of different brackets in reducing enamel demineralization indirectly. Results from different tests indicate the significant reduction in adhesion, biofilm formation and slow growth of tested bacterial species on brackets coated with Ag + TiO2 and found to be statistically significant lower than control. There was no loss in cell viability in all brackets indicating that the cells are biocompatible with different bracket materials. Scanning electron microscopy showed less bacteria attached with the surface coated with Ag + TiO2 indicated that bacteria were losing adherent nature on coated surface. In conclusion, TiO2+Ag coating on stainless steel brackets possessed anti-adherent properties and also have demonstrable antibacterial properties therefore helps in preventing dental caries and plaque accumulation indirectly. The cell compatibility of TiO2+Ag coated brackets is superior to the uncoated samples therefore can be used in orthodontics as it not only provide suitable antimicrobial activity and resistance to biofilm formation but also sustained the cell viability of human gingival fibroblast (HGF) cell lines. Copyright © 2017 Elsevier Ltd. All rights reserved.

Blockade of GpIIb/IIIa inhibits the release of vascular endothelial growth factor (VEGF) from tumor cell-activated platelets and experimental metastasis.

PubMed

Amirkhosravi, A; Amaya, M; Siddiqui, F; Biggerstaff, J P; Meyer, T V; Francis, J L

1999-01-01

Evidence that platelets play a role in tumor metastasis includes the observation of circulating tumor cell-platelet aggregates and the anti-metastatic effect of thrombocytopenia and anti-platelet drugs. Platelets have recently been shown to contain vascular endothelial growth factor (VEGF) which is released during clotting. We therefore studied the effects of (1) tumor cell-platelet adherence and tumor cell TF activity on platelet VEGF release; and (2) the effects of GpIIb/IIIa blockade on tumor cell-induced platelet VEGF release, tumor cell-induced thrombocytopenia and experimental metastasis. Adherent A375 human melanoma cells (TF+) and KG1 myeloid leukemia (TF-) cells were cultured in RPMI containing 10% fetal bovine serum. Platelet-rich plasma was obtained from normal citrated whole blood and the presence of VEGF (34 and 44 kDa isoforms) confirmed by immunoblotting. Platelet-rich plasma with or without anti-GpIIb/IIIa (Abciximab) was added to A375 monolayers and supernatant VEGF measured by ELISA. Tumor cell-induced platelet activation and release were determined by CD62P expression and serotonin release respectively. In vitro, tumor cell-platelet adherence was evaluated by flow cytometry. In vivo, thrombocytopenia and lung seeding were assessed 30 min and 18 days, respectively, after i.v. injection of Lewis Lung carcinoma (LL2) cells into control or murine 7E3 F(ab')(2) (6 mg/ kg) athymic rats. Maximal in vitro platelet activation (72% serotonin release) occurred 30 min after adding platelets to tumor cells. At this time, 87% of the A375 cells had adhered to platelets. Abciximab significantly (P<0.05) reduced platelet adherence to tumor cells as evidenced by flow cytometry. Incubation of A375 cells with platelets induced VEGF release in a time-dependent manner. This release was significantly inhibited by Abciximab (81% at 30 min; P<0.05). In the presence of fibrinogen and FII, VEGF release induced by A375 (TF+) cells was significantly higher than that induced by KG1 (TF-) cells (105.5+/-24 vs. 42+/-7 pg/ml; P<0.001). Omitting fibrinogen or FII from the reaction mixture markedly decreased VEGF release. In vivo, GpIIb/IIIa blockade with murine 7E3 F(ab')(2) reduced LL2 tumor cell-induced thrombocytopenia by 90% (P<0.001) and lung seeding by 82% (P<0.05). We conclude that TF-bearing tumor cells can activate platelets largely via thrombin generation, and that such activation is associated with release of VEGF. This may enhance metastasis, possibly by increasing extravasation at points of adhesion to vascular endothelium.

Manipulation of a quasi-natural cell block for high-efficiency transplantation of adherent somatic cells

PubMed Central

Chung, H.J.; Hassan, M.M.; Park, J.O.; Kim, H.J.; Hong, S.T.

2015-01-01

Recent advances have raised hope that transplantation of adherent somatic cells could provide dramatic new therapies for various diseases. However, current methods for transplanting adherent somatic cells are not efficient enough for therapeutic applications. Here, we report the development of a novel method to generate quasi-natural cell blocks for high-efficiency transplantation of adherent somatic cells. The blocks were created by providing a unique environment in which cultured cells generated their own extracellular matrix. Initially, stromal cells isolated from mice were expanded in vitro in liquid cell culture medium followed by transferring the cells into a hydrogel shell. After incubation for 1 day with mechanical agitation, the encapsulated cell mass was perforated with a thin needle and then incubated for an additional 6 days to form a quasi-natural cell block. Allograft transplantation of the cell block into C57BL/6 mice resulted in perfect adaptation of the allograft and complete integration into the tissue of the recipient. This method could be widely applied for repairing damaged cells or tissues, stem cell transplantation, ex vivo gene therapy, or plastic surgery. PMID:25742639

Adherence to On-Time ART Drug Pick-Up and Its Association with CD4 Changes and Clinical Outcomes Amongst HIV Infected Adults on First-Line Antiretroviral Therapy in Nigerian Hospitals.

PubMed

Anoje, Chukwuemeka; Agu, Kenneth Anene; Oladele, Edward A; Badru, Titilope; Adedokun, Oluwasanmi; Oqua, Dorothy; Khamofu, Hadiza; Adebayo, Olufunso; Torpey, Kwasi; Chabikuli, Otto Nzapfurundi

2017-02-01

Medication adherence is a major determinant of antiretroviral treatment (ART) success. Promptness in medication refill pick-ups may give an indication of medication adherence. This study determined medication refill adherence among HIV positive patients on ART and its association with treatment outcomes in HIV treatment centers in Nigeria. This retrospective multi-center cohort study involved a review of ART refill records for 3534 HIV-positive patients aged 18-60 years who initiated first-line ART between January 2008 and December 2009 and were on therapy for ≥18 months after ART initiation. Drug refill records of these patients for 10 consecutive refill visits after ART initiation were analyzed. The first ten consecutive refill appointment-keeping rates after ART initiation ranged from 64.3 % to 76.1 % which decreased with successive visits. Altogether, 743 (21.1 %) patients were deemed adherent, meaning they picked up their drugs within 7 days of the drug refill appointment date on at least nine out of ten refill visits. The adherent group of patients had a mean CD4 cells increase of 206 ± 6.1 cells/dl after 12 months of ART compared to 186 ± 7.1 cells/dl reported among the nonadherent group (p = 0.0145). The proportion of patients in the adherent category who showed no OIs after 12 months on ART (81 %) was significantly higher when compared to the proportion in the non-adherent category (23.5 %), (p = 0.008). The multivariate analysis showed that the odds of being adherent was 2-3 times more in patients who had a baseline CD4 count of less than 200 cells/dl compared to those with a baseline CD4 of >350 cells/dl. (AOR 2.43, 95 % CI 1.62-3.66). In addition, for patients with baseline CD4 cell count of 201-350 cells/dl, the odds of being adherent was found to be 1.9 compared to those with baseline CD4 of greater than 350 cells/dl (AOR 1.93, 95 % CI 1.27-2.94). Pharmacy refill data can serve as an adherence measure. Adherence to on-time drug pickup on ≥90 % of refill appointments was associated with a better CD4 count response and a reduction in the presence of opportunistic infections in ART patients after 12 months of treatment.

High-Throughput Cancer Cell Sphere Formation for 3D Cell Culture.

PubMed

Chen, Yu-Chih; Yoon, Euisik

2017-01-01

Three-dimensional (3D) cell culture is critical in studying cancer pathology and drug response. Though 3D cancer sphere culture can be performed in low-adherent dishes or well plates, the unregulated cell aggregation may skew the results. On contrary, microfluidic 3D culture can allow precise control of cell microenvironments, and provide higher throughput by orders of magnitude. In this chapter, we will look into engineering innovations in a microfluidic platform for high-throughput cancer cell sphere formation and review the implementation methods in detail.

Analysis of cellular adhesion on superhydrophobic and superhydrophilic vertically aligned carbon nanotube scaffolds.

PubMed

Machado, M M; Lobo, A O; Marciano, F R; Corat, E J; Corat, M A F

2015-03-01

We analyzed GFP cells after 24h cultivated on superhydrophilic vertically aligned carbon nanotube scaffolds. We produced two different densities of VACNT scaffolds on Ti using Ni or Fe catalysts. A simple and fast oxygen plasma treatment promoted the superhydrophilicity of them. We used five different substrates, such as: as-grown VACNT produced using Ni as catalyst (Ni), as-grown VACNT produced using Fe as catalyst (Fe), VACNT-O produced using Ni as catalyst (NiO), VACNT-O produced using Fe as catalyst (FeO) and Ti (control). The 4',6-diamidino-2-phenylindole reagent nuclei stained the adherent cells cultivated on five different analyzed scaffolds. We used fluorescence microscopy for image collect, ImageJ® to count adhered cell and GraphPad Prism 5® for statistical analysis. We demonstrated in crescent order: Fe, Ni, NiO, FeO and Ti scaffolds that had an improved cellular adhesion. Oxygen treatment associated to high VACNT density (group FeO) presented significantly superior cell adhesion up to 24h. However, they do not show significant differences compared with Ti substrates (control). We demonstrated that all the analyzed substrates were nontoxic. Also, we proposed that the density and hydrophilicity influenced the cell adhesion behavior. Copyright © 2014 Elsevier B.V. All rights reserved.

PCR amplification and genetic analysis in a microwell cell culturing chip.

PubMed

Lindström, Sara; Hammond, Maria; Brismar, Hjalmar; Andersson-Svahn, Helene; Ahmadian, Afshin

2009-12-21

We have previously described a microwell chip designed for high throughput, long-term single-cell culturing and clonal analysis in individual wells providing a controlled way of studying high numbers of individual adherent or non-adherent cells. Here we present a method for the genetic analysis of cells cultured on-chip by PCR and minisequencing, demonstrated using two human adherent cell lines: one wild type and one with a single-base mutation in the p53 gene. Five wild type or mutated cells were seeded per well (in a defined set of wells, each holding 500 nL of culture medium) in a 672-microwell chip. The cell chip was incubated overnight, or cultured for up to five days, depending on the desired colony size, after which the cells were lysed and subjected to PCR directly in the wells. PCR products were detected, in the wells, using a biotinylated primer and a fluorescently labelled primer, allowing the products to be captured on streptavidin-coated magnetic beads and detected by a fluorescence microscope. In addition, to enable genetic analysis by minisequencing, the double-stranded PCR products were denatured and the immobilized strands were kept in the wells by applying a magnetic field from the bottom of the wells while the wells were washed, a minisequencing reaction mixture was added, and after incubation in appropriate conditions the expected genotypes were detected in the investigated microwells, simultaneously, by an array scanner. We anticipate that the technique could be used in mutation frequency screening, providing the ability to correlate cells' proliferative heterogeneity to their genetic heterogeneity, in hundreds of samples simultaneously. The presented method of single-cell culture and DNA amplification thus offers a potentially powerful alternative to single-cell PCR, with advantageous robustness and sensitivity.

A rapid co-culture stamping device for studying intercellular communication.

PubMed

Hassanzadeh-Barforoushi, Amin; Shemesh, Jonathan; Farbehi, Nona; Asadnia, Mohsen; Yeoh, Guan Heng; Harvey, Richard P; Nordon, Robert E; Warkiani, Majid Ebrahimi

2016-10-18

Regulation of tissue development and repair depends on communication between neighbouring cells. Recent advances in cell micro-contact printing and microfluidics have facilitated the in-vitro study of homotypic and heterotypic cell-cell interaction. Nonetheless, these techniques are still complicated to perform and as a result, are seldom used by biologists. We report here development of a temporarily sealed microfluidic stamping device which utilizes a novel valve design for patterning two adherent cell lines with well-defined interlacing configurations to study cell-cell interactions. We demonstrate post-stamping cell viability of >95%, the stamping of multiple adherent cell types, and the ability to control the seeded cell density. We also show viability, proliferation and migration of cultured cells, enabling analysis of co-culture boundary conditions on cell fate. We also developed an in-vitro model of endothelial and cardiac stem cell interactions, which are thought to regulate coronary repair after myocardial injury. The stamp is fabricated using microfabrication techniques, is operated with a lab pipettor and uses very low reagent volumes of 20 μl with cell injection efficiency of >70%. This easy-to-use device provides a general strategy for micro-patterning of multiple cell types and will be important for studying cell-cell interactions in a multitude of applications.

A rapid co-culture stamping device for studying intercellular communication

NASA Astrophysics Data System (ADS)

Hassanzadeh-Barforoushi, Amin; Shemesh, Jonathan; Farbehi, Nona; Asadnia, Mohsen; Yeoh, Guan Heng; Harvey, Richard P.; Nordon, Robert E.; Warkiani, Majid Ebrahimi

2016-10-01

Regulation of tissue development and repair depends on communication between neighbouring cells. Recent advances in cell micro-contact printing and microfluidics have facilitated the in-vitro study of homotypic and heterotypic cell-cell interaction. Nonetheless, these techniques are still complicated to perform and as a result, are seldom used by biologists. We report here development of a temporarily sealed microfluidic stamping device which utilizes a novel valve design for patterning two adherent cell lines with well-defined interlacing configurations to study cell-cell interactions. We demonstrate post-stamping cell viability of >95%, the stamping of multiple adherent cell types, and the ability to control the seeded cell density. We also show viability, proliferation and migration of cultured cells, enabling analysis of co-culture boundary conditions on cell fate. We also developed an in-vitro model of endothelial and cardiac stem cell interactions, which are thought to regulate coronary repair after myocardial injury. The stamp is fabricated using microfabrication techniques, is operated with a lab pipettor and uses very low reagent volumes of 20 μl with cell injection efficiency of >70%. This easy-to-use device provides a general strategy for micro-patterning of multiple cell types and will be important for studying cell-cell interactions in a multitude of applications.

Inhibition of lymphocyte proliferative responses to Helicobacter pylori by plastic adherent cells.

PubMed

Uyub, A M; Anuar, A K

2001-03-01

A study was carried out on 49 H. pylori-positive and 11 H. pylori-negative patients to determine the reactivity of peripheral blood lymphocytes (PBL) to phytohemagglutinin (PHA) and acid glycine extract (AGE) of H. pylori, and to identify cells responsible for imunosuppression. Based on response to PHA stimulation, cell-mediated immunity of all patients were competent. In some patients, however, response to AGE of H. pylori was suppressed by plastic adherent cells. This study provided evidence of the presence of plastic adherent suppressor cells which suppressed PBL response to AGE of H. pylori but not to PHA suggesting that immunosuppression is antigen specific. There is also an indication that immunosuppression may be species-specific as PBL devoid of plastic adherent cells only responded to stimulation by AGE of H. pylori but not that to AGE of C. jejuni.

Regulation of Biofilm Formation in Escherichia coli O157:H7

USDA-ARS?s Scientific Manuscript database

Escherichia coli O157:H7 encodes a variety of genetic factors for adherence to epithelial cells and to abiotic surfaces. While adherence to epithelial cells culminates in the formation of characteristic attaching and effacing (A/E) lesions, adherence to abiotic surfaces represents a prelude to the f...

Proteins other than the locus of enterocyte effacement-encoded proteins contribute to Escherichia coli O157:H7 adherence to bovine rectoanal junction stratified squamous epithelial cells

PubMed Central

2012-01-01

Background In this study, we present evidence that proteins encoded by the Locus of Enterocyte Effacement (LEE), considered critical for Escherichia coli O157 (O157) adherence to follicle-associated epithelial (FAE) cells at the bovine recto-anal junction (RAJ), do not appear to contribute to O157 adherence to squamous epithelial (RSE) cells also constituting this primary site of O157 colonization in cattle. Results Antisera targeting intimin-γ, the primary O157 adhesin, and other essential LEE proteins failed to block O157 adherence to RSE cells, when this pathogen was grown in DMEM, a culture medium that enhances expression of LEE proteins. In addition, RSE adherence of a DMEM-grown-O157 mutant lacking the intimin protein was comparable to that seen with its wild-type parent O157 strain grown in the same media. These adherence patterns were in complete contrast to that observed with HEp-2 cells (the adherence to which is mediated by intimin-γ), assayed under same conditions. This suggested that proteins other than intimin-γ that contribute to adherence to RSE cells are expressed by this pathogen during growth in DMEM. To identify such proteins, we defined the proteome of DMEM-grown-O157 (DMEM-proteome). GeLC-MS/MS revealed that the O157 DMEM-proteome comprised 684 proteins including several components of the cattle and human O157 immunome, orthologs of adhesins, hypothetical secreted and outer membrane proteins, in addition to the known virulence and LEE proteins. Bioinformatics-based analysis of the components of the O157 DMEM proteome revealed several new O157-specific proteins with adhesin potential. Conclusion Proteins other than LEE and intimin-γ proteins are involved in O157 adherence to RSE cells at the bovine RAJ. Such proteins, with adhesin potential, are expressed by this human pathogen during growth in DMEM. Ongoing experiments to evaluate their role in RSE adherence should provide both valuable insights into the O157-RSE interactions and new targets for more efficacious anti-adhesion O157 vaccines. PMID:22691138

Effects of Tacrolimus or Sirolimus on the adhesion of vascular wall cells: Controlled in-vitro comparison study.

PubMed

Krüger-Genge, A; Hiebl, B; Franke, R P; Lendlein, A; Jung, F

2017-01-01

In drug eluting stents the cytostatic drugs Sirolimus or Tacrolimus are used to inhibit blood vessel restenosis by limiting the proliferation of smooth muscle cells. However, the cytostatic activity of both drugs was shown to be not cell specific and could also affect the stent endothelialisation, respectively. Currently, only limited in vitro data are available about the impact of Sirolimus and Tacrolimus on endothelial cell proliferation over a broad concentration range. To answer this question the following study was performed.Commercially obtained HUVEC were expanded with DMEM cell culture medium (GIBCO, Germany) supplemented with 5 vol% fetal calf serum on non-coated regular polystyrene-based 24-multiwell plates. For drug testings 2×104 cells/cm2 were seeded and grown for 24 h until 30-40% of the multiwell surfaces were covered and then exposed to Sirolimus (1.0×10-11 - 1.0×10-5 mol/l) or Tacrolimus (2.0×10-8 - 6.2×10-5 mol/l), both dissolved in DMSO. 12, 24 and 48 h after adding the drugs cell numbers per area were quantified by counting the cells in six wells with four fields of view per well, representing 0.6 mm2, using a confocal laser microscope.After 48 h of cell growth in the drug-free cell culture medium, the HUVEC number increased from 2.0×104 to 3.55×104 cells/cm2 (mean cell doubling time: 53.6 h, n = 6). At lower concentrations (≤2.0×10-6 mol/l) Tacrolimus reduced the number of adherent HUVEC significantly less than Sirolimus (p < 0.05). However, at higher concentrations (≥2.07×10-5 mol/l) the effect of Tacrolimus on the number of adherent endothelial cells was significantly greater than that of Sirolimus (p < 0.05). At the highest concentration applied (6.22×10-5 mol/l), Tacrolimus induced detachment of all HUVECs within 12 h after drug application. The number of adherent HUVEC decreased only slightly (about 9%) after Sirolimus application at the highest concentration (1.09×10-5 mol/l).These data show that in a non-flow model the cytostatic drug Tacrolimus reduced the number of adherent endothelial cells less than Sirolimus, as long as the drug concentration did not surpass 10-6 mol/l. At the limits of solubility, Sirolimus (1×10-5 mol/l) reduced the number of adherent endothelial cells less than Tacrolimus (6×10-5 mol/l), which induced detachment of endothelial cells.

Adherence to Mediterranean diet is associated with methylation changes in inflammation-related genes in peripheral blood cells.

PubMed

Arpón, A; Riezu-Boj, J I; Milagro, F I; Marti, A; Razquin, C; Martínez-González, M A; Corella, D; Estruch, R; Casas, R; Fitó, M; Ros, E; Salas-Salvadó, J; Martínez, J A

2016-08-01

Epigenetic processes, including DNA methylation, might be modulated by environmental factors such as the diet, which in turn have been associated with the onset of several diseases such as obesity or cardiovascular events. Meanwhile, Mediterranean diet (MedDiet) has demonstrated favourable effects on cardiovascular risk, blood pressure, inflammation and other complications related to excessive adiposity. Some of these effects could be mediated by epigenetic modifications. Therefore, the objective of this study was to investigate whether the adherence to MedDiet is associated with changes in the methylation status from peripheral blood cells. A subset of 36 individuals was selected within the Prevención con Dieta Mediterránea (PREDIMED)-Navarra study, a randomised, controlled, parallel trial with three groups of intervention in high cardiovascular risk volunteers, two with a MedDiet and one low-fat control group. Changes in methylation between baseline and 5 years were studied. DNA methylation arrays were analysed by several robust statistical tests and functional classifications. Eight genes related to inflammation and immunocompetence (EEF2, COL18A1, IL4I1, LEPR, PLAGL1, IFRD1, MAPKAPK2, PPARGC1B) were finally selected as changes in their methylation levels correlated with adherence to MedDiet and because they presented sensitivity related to a high variability in methylation changes. Additionally, EEF2 methylation levels positively correlated with concentrations of TNF-α and CRP. This report is apparently the first showing that adherence to MedDiet is associated with the methylation of the reported genes related to inflammation with a potential regulatory impact.

Yield and proliferation rate of adipose-derived stromal cells as a function of age, body mass index and harvest site-increasing the yield by use of adherent and supernatant fractions?

PubMed

Buschmann, Johanna; Gao, Shuping; Härter, Luc; Hemmi, Sonja; Welti, Manfred; Werner, Clement M L; Calcagni, Maurizio; Cinelli, Paolo; Wanner, Guido A

2013-09-01

Adipose-derived stem cells are easily accessed and have a relatively high density compared with other mesenchymal stromal cells. Isolation protocols of adipose-derived stem cells (ASC) rely on the cell's ability to adhere to tissue culture plastic overnight. It was evaluated whether the floating ASC fractions are also of interest for cell-based therapies. In addition, the impact of age, body mass index (BMI) and harvest site was assessed. The surface protein profile with the use of flow cytometry, the cell yield and the doubling time of passages 4, 5 and 6 of ASC from 30 donors were determined. Adherent and supernatant fractions were compared. The impact of age, BMI and harvest site on cell yield and doubling times was determined. Both adherent and supernatant fractions showed high mean fluorescence intensities for CD13, CD29, CD44, CD73, CD90 and CD105 and comparatively low mean fluorescence intensities for CD11b, CD62L, intracellular adhesion molecule-1 and CD34. Doubling times of adherent and supernatant fractions did not differ significantly. Whereas the old age group had a significantly lower cell yield compared with the middle aged group, BMI and harvest site had no impact on cell yield. Finally, doubling times for passages 4, 5 and 6 were not influenced by the age and BMI of the donors, nor the tissue-harvesting site. The floating ASC fraction is an equivalent second cell source just like the adherent ASC fraction. Donor age, BMI and harvest site do not influence cell yield and proliferation rate. Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Atypical enteropathogenic Escherichia coli that contains functional locus of enterocyte effacement genes can be attaching-and-effacing negative in cultured epithelial cells.

PubMed

Rocha, Sérgio P D; Abe, Cecilia M; Sperandio, Vanessa; Bando, Silvia Y; Elias, Waldir P

2011-05-01

Enteropathogenic Escherichia coli (EPEC) induces a characteristic histopathology on enterocytes known as the attaching-and-effacing (A/E) lesion, which is triggered by proteins encoded by the locus of enterocyte effacement (LEE). EPEC is currently classified as typical EPEC (tEPEC) and atypical EPEC (aEPEC), based on the presence or absence of the EPEC adherence factor plasmid, respectively. Here we analyzed the LEE regions of three aEPEC strains displaying the localized adherence-like (LAL), aggregative adherence (AA), and diffuse adherence (DA) patterns on HEp-2 cells as well as one nonadherent (NA) strain. The adherence characteristics and the ability to induce A/E lesions were investigated with HeLa, Caco-2, T84, and HT29 cells. The adherence patterns and fluorescent actin staining (FAS) assay results were reproducible with all cell lines. The LEE region was structurally intact and functional in all strains regardless of their inability to cause A/E lesions. An EspF(U)-expressing plasmid (pKC471) was introduced into all strains, demonstrating no influence of this protein on either the adherence patterns or the capacity to cause A/E of the adherent strains. However, the NA strain harboring pKC471 expressed the LAL pattern and was able to induce A/E lesions on HeLa cells. Our data indicate that FAS-negative aEPEC strains are potentially able to induce A/E in vivo, emphasizing the concern about this test for the determination of aEPEC virulence. Also, the presence of EspF(U) was sufficient to provide an adherent phenotype for a nonadherent aEPEC strain via the direct or indirect activation of the LEE4 and LEE5 operons.

A Macro-to-Micro Interface for the Control of Cellular Organization

PubMed Central

Hui, Elliot E.; Li, Chun; Agrawal, Amit; Bhatia, Sangeeta N.

2015-01-01

The spatial organization of cellular communities plays a fundamental role in determining intercellular communication and emergent behavior. However, few tools exist to modulate tissue organization at the scale of individual cells, particularly in the case of dynamic manipulation. Micromechanical reconfigurable culture achieves dynamic control of tissue organization by culturing adherent cells on microfabricated plates that can be shifted to reorganize the arrangement of the cells. While biological studies utilizing this approach have been previously reported, this paper focuses on the engineering of the device, including the mechanism for translating manual manipulation to precise microscale position control, fault-tolerant design for manufacture, and the synthetic-to-living interface. PMID:26167106

Investigation on cytoskeleton dynamics for no-adherent cells subjected to point-like stimuli by digital holographic microscopy and holographic optical trapping

NASA Astrophysics Data System (ADS)

Miccio, Lisa; Merola, Francesco; Memmolo, Pasquale; Mugnano, Martina; Fusco, Sabato; Netti, Paolo A.; Ferraro, Pietro

2014-05-01

Guiding, controlling and studying cellular functions are challenging themes in the biomedical field, as they are fundamental prerequisites for new therapeutic strategies from tissue regeneration to controlled drug delivery. In recent years, multidisciplinary studies in nanotechnology offer new tools to investigate important biophysical phenomena in response to the local physical characteristics of the extracellular environment, some examples are the mechanisms of cell adhesion, migration, communication and differentiation. Indeed for reproducing the features of the extracellular matrix in vitro, it is essential to develop active devices that evoke as much as possible the natural cellular environment. Our investigation is in the framework of studying and clarifying the biophysical mechanisms of the interaction between cells and the microenvironment in which they exist. We implement an optical tweezers setup to investigate cell material interaction and we use Digital Holography as non-invasive imaging technique in microscopy. We exploit Holographic Optical Tweezers arrangement in order to trap and manage functionalized micrometric latex beads to induce mechanical deformation in suspended cells. A lot of papers in literature examine the dynamics of the cytoskeleton when cells adhere on substrates and nowadays well established cell models are based on such research activities. Actually, the natural cell environment is made of a complex extracellular matrix and the single cell behavior is due to intricate interactions with the environment and are strongly correlated to the cell-cell interactions. Our investigation is devoted to understand the inner cell mechanism when it is mechanically stressed by point-like stimulus without the substrate influence.

Probiotics inhibit enteropathogenic E. coli adherence in vitro by inducing intestinal mucin gene expression.

PubMed

Mack, D R; Michail, S; Wei, S; McDougall, L; Hollingsworth, M A

1999-04-01

Probiotic agents, live microorganisms with beneficial effects for the host, may offer an alternative to conventional antimicrobials in the treatment and prevention of enteric infections. The probiotic agents Lactobacillus plantarum 299v and Lactobacillus rhamnosus GG quantitatively inhibited the adherence of an attaching and effacing pathogenic Escherichia coli to HT-29 intestinal epithelial cells but did not inhibit adherence to nonintestinal HEp-2 cells. HT-29 cells were grown under conditions that induced high levels of either MUC2 or MUC3 mRNA, but HEp-2 cells expressed only minimal levels of MUC2 and no MUC3 mRNA. Media enriched for MUC2 and MUC3 mucin were added exogenously to binding assays and were shown to be capable of inhibiting enteropathogen adherence to HEp-2 cells. Incubation of L. plantarum 299v with HT-29 cells increased MUC2 and MUC3 mRNA expression levels. From these in vitro studies, we propose the hypothesis that the ability of probiotic agents to inhibit adherence of attaching and effacing organisms to intestinal epithelial cells is mediated through their ability to increase expression of MUC2 and MUC3 intestinal mucins.

Slow-Adhering Stem Cells Derived from Injured Skeletal Muscle Have Improved Regenerative Capacity

DTIC Science & Technology

2011-08-01

images. Flow Cytometry Assay of Stem Cell Markers SASCs (1 105) isolated from noninjured or injured muscle were collected and washed twice with...muscle. Results of flow cytometry further verified Sca-1 and CD34 expression in isolated SASCs, and a greater percentage of cells were positive for Sca-1...from both injured and control noninjured muscle were analyzed using flow cytometry for the immunofluorescent signal of Sca-1 and CD34. Results

Phospholipase C and perfringolysin O from Clostridium perfringens upregulate endothelial cell-leukocyte adherence molecule 1 and intercellular leukocyte adherence molecule 1 expression and induce interleukin-8 synthesis in cultured human umbilical vein endothelial cells.

PubMed Central

Bryant, A E; Stevens, D L

1996-01-01

Clostridium perfringens phospholipase C (PLC) and perfringolysin O (PFO) differentially induced human umbilical vein endothelial cell expression and synthesis of endothelial cell-leukocyte adherence molecule-1 (ELAM-1), intracellular leukocyte adherence molecule-1 (ICAM-1), and interleukin-8 (IL-8). PLC strongly induced expression of ELAM-1, ICAM-1, and IL-8, while PFO stimulated early ICAM-1 expression but did not promote ELAM-1 expression or IL-8 synthesis. PLC caused human umbilical vein endothelial cells to assume a fibroblastoid morphology, whereas PFO, in high concentrations or after prolonged low-dose toxin exposure, caused cell death. The toxin-induced expression of proadhesive and activational proteins and direct cytopathic effects may contribute to the leukostasis, vascular compromise, and capillary leak characteristics of C. perfringens gas gangrene. PMID:8557365

Electronic monitoring of adherence to inhaled corticosteroids: an essential tool in identifying severe asthma in children.

PubMed

Jochmann, Anja; Artusio, Luca; Jamalzadeh, Angela; Nagakumar, Prasad; Delgado-Eckert, Edgar; Saglani, Sejal; Bush, Andrew; Frey, Urs; Fleming, Louise J

2017-12-01

International guidelines recommend that severe asthma can only be diagnosed after contributory factors, including adherence, have been addressed. Accurate assessment of adherence is difficult in clinical practice. We hypothesised that electronic monitoring in children would identify nonadherence, thus delineating the small number with true severe asthma.Asthmatic children already prescribed inhaled corticosteroids were prospectively recruited and persistence of adherence assessed using electronic monitoring devices. Spirometry, airway inflammation and asthma control were measured at the start and end of the monitoring period.93 children (62 male; median age 12.4 years) were monitored for a median of 92 days. Median (range) monitored adherence was 74% (21-99%). We identified four groups: 1) good adherence during monitoring with improved control, 24% (likely previous poor adherence); 2) good adherence with poor control, 18% (severe therapy-resistant asthma); 3) poor adherence with good control, 26% (likely overtreated); and 4) poor adherence with poor control, 32%. No clinical parameter prior to monitoring distinguished these groups.Electronic monitoring is a useful tool for identifying children in whom a step up in treatment is indicated. Different approaches are needed in those who are controlled when adherent or who are nonadherent. Electronic monitoring is essential in a paediatric severe asthma clinic. Copyright ©ERS 2017.

Lactoferrin affects the adherence and invasion of Streptococcus dysgalactiae ssp. dysgalactiae in mammary epithelial cells.

PubMed

O'Halloran, Fiona; Beecher, Christine; Chaurin, Valerie; Sweeney, Torres; Giblin, Linda

2016-06-01

Streptococcus dysgalactiae ssp. dysgalactiae is an important causative agent of bovine mastitis worldwide. Lactoferrin is an innate immune protein that is associated with many functions including immunomodulatory, antiproliferative, and antimicrobial properties. This study aimed to investigate the interactions between lactoferrin and a clinical bovine mastitis isolate, Strep. dysgalactiae ssp. dysgalactiae DPC5345. Initially a deliberate in vivo bovine intramammary challenge was performed with Strep. dysgalactiae DPC5345. Results demonstrated a significant difference in lactoferrin mRNA levels in milk cells between the control and infused quarters 7h postinfusion. Milk lactoferrin levels in the Strep. dysgalactiae DPC5345 infused quarters were significantly increased compared with control quarters at 48h postinfusion. In vitro studies demonstrated that lactoferrin had a bacteriostatic effect on the growth of Strep. dysgalactiae DPC5345 and significantly decreased the ability of the bacteria to internalize into HC-11 mammary epithelial cells. Confocal microscopy images of HC-11 cells exposed to Strep. dysgalactiae and lactoferrin further supported this effect by demonstrating reduced invasion of bacteria to HC-11 cells. The combined data suggest that a bovine immune response to Strep. dysgalactiae infection includes a significant increase in lactoferrin expression in vivo, and based on in vitro data, lactoferrin limits mammary cell invasion of this pathogen by binding to the bacteria and preventing its adherence. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Investigation of Immunoregulatory Alphaglobulin (IRA) in Shock and Trauma.

DTIC Science & Technology

1980-07-01

rice whose limbs were amputated 2 days earlier Were fraction by adherence to glass Petri dishes or nylon wool columns (2 cycl,7), or by treatin Wi...to alloantigens. suggesting the presence of suppressor cells. The suppressor cells were found to adhere to glass and to nylon wool columns. They were...negative cell population capable of adhering to glass and nylon wool, Presumably macrophages. was responsible for inhibiting the response of lymphocytes

Adherence rates to ferric citrate as compared to active control in patients with end stage kidney disease on dialysis.

PubMed

Jalal, Diana; McFadden, Molly; Dwyer, Jamie P; Umanath, Kausik; Aguilar, Erwin; Yagil, Yoram; Greco, Barbara; Sika, Mohammed; Lewis, Julia B; Greene, Tom; Goral, Simin

2017-04-01

Oral phosphate binders are the main stay of treatment of hyperphosphatemia. Adherence rates to ferric citrate, a recently approved phosphate binder, are unknown. We conducted a post-hoc analysis to evaluate whether adherence rates were different for ferric citrate vs. active control in 412 subjects with end stage kidney disease (ESKD) who were randomized to ferric citrate vs. active control (sevelamer carbonate and/or calcium acetate). Adherence was defined as percent of actual number of pills taken to total number of pills prescribed. There were no significant differences in baseline characteristics including gender, race/ethnicity, and age between the ferric citrate and active control groups. Baseline phosphorus, calcium, and parathyroid hormone levels were similar. Mean (SD) adherence was 81.4% (17.4) and 81.7% (15.9) in the ferric citrate and active control groups, respectively (P = 0.88). Adherence remained similar between both groups after adjusting for gender, race/ethnicity, age, cardiovascular disease (CVD), and diabetic nephropathy (mean [95% CI]: 81.4% [78.2, 84.6] and 81.5% [77.7, 85.2] for ferric citrate and active control, respectively). Gender, race/ethnicity, age, and diagnosis of diabetic nephropathy did not influence adherence to the prescribed phosphate binder. Subjects with CVD had lower adherence rates to phosphate binder; this was significant only in the active control group. Adherence rates to the phosphate binder, ferric citrate, were similar to adherence rates to active control. Similar adherence rates to ferric citrate are notable since tolerance to active control was an entry criteria and the study was open label. Gender, race/ethnicity, nor age influenced adherence. © 2016 International Society for Hemodialysis.

Bit-1 Mediates Integrin-dependent Cell Survival through Activation of the NFκB Pathway*

PubMed Central

Griffiths, Genevieve S.; Grundl, Melanie; Leychenko, Anna; Reiter, Silke; Young-Robbins, Shirley S.; Sulzmaier, Florian J.; Caliva, Maisel J.; Ramos, Joe W.; Matter, Michelle L.

2011-01-01

Loss of properly regulated cell death and cell survival pathways can contribute to the development of cancer and cancer metastasis. Cell survival signals are modulated by many different receptors, including integrins. Bit-1 is an effector of anoikis (cell death due to loss of attachment) in suspended cells. The anoikis function of Bit-1 can be counteracted by integrin-mediated cell attachment. Here, we explored integrin regulation of Bit-1 in adherent cells. We show that knockdown of endogenous Bit-1 in adherent cells decreased cell survival and re-expression of Bit-1 abrogated this effect. Furthermore, reduction of Bit-1 promoted both staurosporine and serum-deprivation induced apoptosis. Indeed knockdown of Bit-1 in these cells led to increased apoptosis as determined by caspase-3 activation and positive TUNEL staining. Bit-1 expression protected cells from apoptosis by increasing phospho-IκB levels and subsequently bcl-2 gene transcription. Protection from apoptosis under serum-free conditions correlated with bcl-2 transcription and Bcl-2 protein expression. Finally, Bit-1-mediated regulation of bcl-2 was dependent on focal adhesion kinase, PI3K, and AKT. Thus, we have elucidated an integrin-controlled pathway in which Bit-1 is, in part, responsible for the survival effects of cell-ECM interactions. PMID:21383007

Evaluation of a Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) assay (Keystone Sym)

EPA Science Inventory

Our goal is to establish an in vitro model system to evaluate chemical effects using a single stem cell culture technique that would improve throughput and provide quantitative markers of differentiation and cell number. To this end, we have used an adherent cell differentiation ...

Screening ToxCast™ Phase I Chemicals in a Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) Assay

EPA Science Inventory

An Adherent Cell Differentiation and Cytotoxicity (ACDC) in vitro assay with mouse embryonic stem cells was used to screen the ToxCast Phase I chemical library for effects on cellular differentiation and cell number. The U.S. Environmental Protection Agency (EPA) established the ...

Clonogenic Assay: Adherent Cells

PubMed Central

Rafehi, Haloom; Orlowski, Christian; Georgiadis, George T.; Ververis, Katherine; El-Osta, Assam; Karagiannis, Tom C.

2011-01-01

The clonogenic (or colony forming) assay has been established for more than 50 years; the original paper describing the technique was published in 19561. Apart from documenting the method, the initial landmark study generated the first radiation-dose response curve for X-ray irradiated mammalian (HeLa) cells in culture1. Basically, the clonogenic assay enables an assessment of the differences in reproductive viability (capacity of cells to produce progeny; i.e. a single cell to form a colony of 50 or more cells) between control untreated cells and cells that have undergone various treatments such as exposure to ionising radiation, various chemical compounds (e.g. cytotoxic agents) or in other cases genetic manipulation. The assay has become the most widely accepted technique in radiation biology and has been widely used for evaluating the radiation sensitivity of different cell lines. Further, the clonogenic assay is commonly used for monitoring the efficacy of radiation modifying compounds and for determining the effects of cytotoxic agents and other anti-cancer therapeutics on colony forming ability, in different cell lines. A typical clonogenic survival experiment using adherent cells lines involves three distinct components, 1) treatment of the cell monolayer in tissue culture flasks, 2) preparation of single cell suspensions and plating an appropriate number of cells in petri dishes and 3) fixing and staining colonies following a relevant incubation period, which could range from 1-3 weeks, depending on the cell line. Here we demonstrate the general procedure for performing the clonogenic assay with adherent cell lines with the use of an immortalized human keratinocyte cell line (FEP-1811)2. Also, our aims are to describe common features of clonogenic assays including calculation of the plating efficiency and survival fractions after exposure of cells to radiation, and to exemplify modification of radiation-response with the use of a natural antioxidant formulation. PMID:21445039

Agglomeration, sedimentation, and cellular toxicity of alumina nanoparticles in cell culture medium

NASA Astrophysics Data System (ADS)

Yoon, Dokyung; Woo, Daekwang; Kim, Jung Heon; Kim, Moon Ki; Kim, Taesung; Hwang, Eung-Soo; Baik, Seunghyun

2011-06-01

The cytotoxicity of alumina nanoparticles (NPs) was investigated for a wide range of concentration (25-200 μg/mL) and incubation time (0-72 h) using floating cells (THP-1) and adherent cells (J774A.1, A549, and 293). Alumina NPs were gradually agglomerated over time although a significant portion of sedimentation occurred at the early stage within 6 h. A decrease of the viability was found in floating (THP-1) and adherent (J774A.1 and A549) cells in a dose-dependent manner. However, the time-dependent decrease in cell viability was observed only in adherent cells (J774A.1 and A549), which is predominantly related with the sedimentation of alumina NPs in cell culture medium. The uptake of alumina NPs in macrophages and an increased cell-to-cell adhesion in adherent cells were observed. There was no significant change in the viability of 293 cells. This in vitro test suggests that the agglomeration and sedimentation of alumina NPs affected cellular viability depending on cell types such as monocytes (THP-1), macrophages (J774A.1), lung carcinoma cells (A549), and embryonic kidney cells (293).

Flow-induced detachment of red blood cells adhering to surfaces by specific antigen-antibody bonds.

PubMed

Xia, Z; Goldsmith, H L; van de Ven, T G

1994-04-01

Fixed spherical swollen human red blood cells of blood type B adhering on a glass surface through antigen-antibody bonds to monoclonal mouse antihuman IgM, adsorbed or covalently linked on the surface, were detached by known hydrodynamic forces created in an impinging jet. The dynamic process of detachment of the specifically bound cells was recorded and analyzed. The fraction of adherent cells remaining on the surface decreased with increasing hydrodynamic force. For an IgM coverage of 0.26%, a tangential force on the order of 100 pN was able to detach almost all of the cells from the surface within 20 min. After a given time of exposure to hydrodynamic force, the fraction of adherent cells remaining increased with time, reflecting an increase in adhesion strength. The characteristic time for effective aging was approximately 4 h. Results from experiments in which the adsorbed antibody molecules were immobilized through covalent coupling and from evanescent wave light scattering of adherent cells, imply that deformation of red cells at the contact area was the principal cause for aging, rather than local clustering of the antibody through surface diffusion. Experiments with latex beads specifically bound to red blood cells suggest that, instead of breaking the antigen-antibody bonds, antigen molecules were extracted from the cell membrane during detachment.

Mother, father, and adolescent self-control and adherence in adolescents with Type 1 diabetes.

PubMed

Lansing, Amy Hughes; Crochiere, Rebecca; Cueto, Carrie; Wiebe, Deborah J; Berg, Cynthia A

2017-06-01

This study explored whether shared self-control across a family system, including adolescent, mother, and father self-control, as well as the interaction of mother and father self-control, was associated with ease of completing adherence tasks and the completion of adherence behaviors related to the Type 1 diabetes (T1D) regimen. One hundred thirty-seven adolescents (M = 13.48 years), mothers, and fathers completed a self-report measure of self-control, while adolescents also self-reported on ease of completing adherence tasks and the frequency with which they completed adherence tasks. Higher adolescent, mother, father, and the interaction of mother and father self-control were each associated with greater adolescent perceptions of ease of completing adherence tasks. Also, greater adolescent perception of ease of adherence mediated the association of higher adolescent, father, and the interaction of mother and father self-control on more frequent adherence behaviors. The results are consistent with the idea that family members may share the load of self-control within the family system. The results point to the importance of assessing and intervening within the entire family system to support improved quality of life and better adherence to the medical regimen in adolescents with Type 1 diabetes. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Cellular and molecular investigations of the adhesion and mechanics of Listeria monocytogenes

NASA Astrophysics Data System (ADS)

Eskhan, Asma Omar

Atomic force microscopy has been used to quantify the adherence and mechanical properties of an array of L. monocytogenes strains and their surface biopolymers. First, eight L. monocytogenes strains that represented the two major lineages of the species were compared for their adherence and mechanics at cellular and molecular levels. Our results indicated that strains of lineage' II were characterized by higher adhesion and Young's moduli, longer and more rigid surface biopolymers and lower specific and nonspecific forces when compared to lineage' I strains. Additionally, adherence and mechanical properties of eight L. monocytogenes epidemic and environmental strains were probed. Our results pointed to that environmental and epidemic strains representative of a given lineage were similar in their adherence and mechanical properties when investigated at a cellular level. However, when the molecular properties of the strains were considered, epidemic strains were characterized by higher specific and nonspecific forces, shorter, denser and more flexible biopolymers compared to environmental strains. Second, the role of environmental pH conditions of growth on the adhesion and mechanics of a pathogenic L. monocytogenes EGDe was investigated. Our results pointed to a transition in the adhesion energies for cells cultured at pH 7. In addition, when the types of molecular forces that govern the adhesion were quantified using Poisson statistical approach and using a new proposed method, specific hydrogen-bond energies dominated the bacterial adhesion process. Such a finding is instrumental to researchers designing methods to control bacterial adhesion. Similarly, bacterial cells underwent a transition in their mechanical properties. We have shown that cells cultured at pH 7 were the most rigid compared to those cultured in lower or higher pH conditions of growth. Due to transitions observed in adherence and mechanics when cells were cultured at pH 7, we hypothesized that adhesion and mechanics are correlated. To test this hypothesis, nonadhesive and adhesive models of contact mechanics were used to estimate Young's moduli. Our results indicated that the nonadhesive model of contact mechanics estimated 18 % more rigid bacterial cells. Our results thus point to the importance of considering molecular details when investigating bacterial adhesion and mechanics.

Is sphere assay useful for the identification of cancer initiating cells of the ovary?

PubMed

Martínez-Serrano, María José; Caballero-Baños, Miguel; Vilella, Ramon; Vidal, Laura; Pahisa, Jaume; Martínez-Roman, Sergio

2015-01-01

Current evidence suggests that the presence of tumor-initiating cells (TICs) in epithelial ovarian cancer (EOC) has a role in chemoresistance and relapse. Surface markers such as CD44(+)/CD24(-), CD117(+), and CD133(+) expression have been reported as potential markers for TICs related to ovarian cancer and tumorigenic cell lines. In this study, we have investigated if spheroid forms are TIC specific or whether they can also be produced by somatic stem cells from healthy tissue in vitro. In addition, we also investigated the specificity of surface markers to identify TICs from papillary serous EOC patients. Cells were obtained from fresh tumors from 10 chemotherapy-naive patients with EOC, and cells from ovarian and tubal epithelium were obtained from 5 healthy menopausal women undergoing surgery for benign pathology and cultured in standard and in selective medium. Cells forming nonadherent spheroids were considered TICs, and the adherent cells were considered as non-TIC-like. Percentages of CD24(+), CD44(+), CD117(+), CD133(+), and vascular endothelial growth factor receptor (VEGF-R)(+) cell surface markers were analyzed by flow cytometry. Four of 10 EOC cell tissues were excluded from the study. Tumor cells cultured in selective medium developed spheroid forms after 1 to 7 weeks in 5 of 6 EOC patients. No spheroid forms were observed in cultures of cells from healthy women. Unlike previously published data, low levels of CD24(+), CD44(+), CD117(+), and VEGF-R(+) expression were observed in spheroid cells, whereas expression of CD133(+) was moderate but higher in adherent cells from papillary serous EOC cells in comparison with adherent cells from controls. Papillary serous EOC contains TICs that form spheroids with low expression of CD44(+), CD24(+), CD117(+) and VEGF-R(+). Further research is required to find specific surface markers to identify papillary serous TICs.

Microfluidic device capable of medium recirculation for non-adherent cell culture

PubMed Central

Dixon, Angela R.; Rajan, Shrinidhi; Kuo, Chuan-Hsien; Bersano, Tom; Wold, Rachel; Futai, Nobuyuki; Takayama, Shuichi; Mehta, Geeta

2014-01-01

We present a microfluidic device designed for maintenance and culture of non-adherent mammalian cells, which enables both recirculation and refreshing of medium, as well as easy harvesting of cells from the device. We demonstrate fabrication of a novel microfluidic device utilizing Braille perfusion for peristaltic fluid flow to enable switching between recirculation and refresh flow modes. Utilizing fluid flow simulations and the human promyelocytic leukemia cell line, HL-60, non-adherent cells, we demonstrate the utility of this RECIR-REFRESH device. With computer simulations, we profiled fluid flow and concentration gradients of autocrine factors and found that the geometry of the cell culture well plays a key role in cell entrapping and retaining autocrine and soluble factors. We subjected HL-60 cells, in the device, to a treatment regimen of 1.25% dimethylsulfoxide, every other day, to provoke differentiation and measured subsequent expression of CD11b on day 2 and day 4 and tumor necrosis factor-alpha (TNF-α) on day 4. Our findings display perfusion sensitive CD11b expression, but not TNF-α build-up, by day 4 of culture, with a 1:1 ratio of recirculation to refresh flow yielding the greatest increase in CD11b levels. RECIR-REFRESH facilitates programmable levels of cell differentiation in a HL-60 non-adherent cell population and can be expanded to other types of non-adherent cells such as hematopoietic stem cells. PMID:24753733

Streptococcus mutans Adherence: Presumptive Evidence for Protein-Mediated Attachment Followed by Glucan-Dependent Cellular Accumulation

PubMed Central

Staat, Robert H.; Langley, Sharon D.; Doyle, R. J.

1980-01-01

Adherence of Streptococcus mutans to smooth surfaces has been attributed to the production of sucrose-derived d-glucans. However, several studies indicate that the bacterium will adhere in the absence of sucrose. The present data confirmed that S. mutans adherence to saliva-coated hydroxyapatite beads in the absence of sucrose is described by the Langmuir equation. The nature of the sucrose-independent adherence was studied with the Persea americana agglutinin as a selective adherence inhibitor. Pretreatment of the bacterium with P. americana agglutinin caused a 10-fold reduction in adherence, and the inhibition was not reversed with the addition of sucrose. Pretreatment of S. mutans with proteases also reduced adherence, regardless of the sucrose content, whereas periodate oxidation and glucanohydrolase treatment of the bacteria reduced sucrose-mediated adherence to the levels found for sucrose-independent adherence. The P. americana agglutinin, glucanohydrolase, and pepsin pretreatment of the cells did not eliminate sucrose-induced agglutination. Scanning electron microscopy showed that short streptococcal chains were bound to saliva-coated hydroxyapatite crystals in the sucrose-independent system, whereas the presence of sucrose caused larger bacterial clumps to be found. A two-reaction model of S. mutans adherence was developed from these data. It is proposed that one reaction is attachment to the tooth pellicle which is mediated by cell-surface proteins rather than glucans or teichoic acids. The other reaction is cellular accumulation mediated by sucrose-derived d-glucans and cell surface lectins. A series of sequential adherence experiments with P. americana agglutinin as a selective inhibitor provided presumptive evidence for the validity of our model of S. mutans adherence. Images Fig. 1 PMID:7380545

Method of making a membrane having hydrophilic and hydrophobic surfaces for adhering cells or antibodies by using atomic oxygen or hydroxyl radicals

NASA Technical Reports Server (NTRS)

Koontz, Steven L. (Inventor); Spaulding, Glenn F. (Inventor)

1994-01-01

A portion of an organic polymer article such as a membrane is made hydrophilic by exposing a hydrophobic surface of the article to a depth of about 50 to about 5000 angstroms to atomic oxygen or hydroxyl radicals at a temperature below 100C., preferably below 40 C, to form a hydrophilic uniform surface layer of hydrophilic hydroxyl groups. The atomic oxygen and hydroxyl radicals are generated by a flowing afterglow microwave discharge, and the surface is outside of a plasma produced by the discharge. A membrane having both hydrophilic and hydrophobic surfaces can be used in an immunoassay by adhering antibodies to the hydrophobic surface. In another embodiment, the membrane is used in cell culturing where cells adhere to the hydrophilic surface. Prior to adhering cells, the hydrophilic surface may be grafted with a compatibilizing compound. A plurality of hydrophilic regions bounded by adjacent hydrophobic regions can be produced such that a maximum of one cell per each hydrophilic region adheres.

A peer adherence support intervention to improve the antiretroviral treatment outcomes of HIV patients in South Africa: the moderating role of family dynamics.

PubMed

Wouters, Edwin; Masquillier, Caroline; Ponnet, Koen; le Roux Booysen, Frederik

2014-07-01

Given the severe shortage of human resources in the healthcare sector in many countries with high HIV prevalence, community-based peer adherence support is being increasingly cited as an integral part of a sustainable antiretroviral treatment (ART) strategy. However, the available scientific evidence on this topic reports discrepant findings on the effectiveness of peer adherence support programmes. These conflicting findings to some extent can be attributed to the lack of attention to the social contexts in which peer adherence support programmes are implemented. This study explores the potential moderating role of family dynamics by assessing the differential impact of peer adherence support in different types of families, based on the theoretical underpinnings of the family functioning framework. These relationships were explored with the aid of multivariate statistical analysis of cross-sectional, post-trial data for a sample of 340 patients interviewed as part of the Effectiveness of Aids Treatment and Support in the Free State (FEATS) study conducted in the public-sector ART programme of the Free State Province of South Africa. The analysis reveals no significant overall differences in CD4 cell count between the intervention group accessing additional peer adherence support and the control group receiving standard care. When controlling for the potential moderating role of family dynamics, however, the outcomes clearly reveal a significant interaction effect between the adherence intervention and the level of family functioning with regard to treatment outcomes. Multi-group analysis demonstrates that peer adherence support has a positive effect on immunological restoration in well-functioning families, while having a negative effect in dysfunctional families. The study outcomes stress the need for peer adherence interventions that are sensitive to the suboptimal contexts in which they are often implemented. Generic, broad-based interventions do not necessarily facilitate the treatment adherence of the most vulnerable patient groups, particularly those without supportive family contexts. Tailoring interventions aimed at creating a health-enabling environment to the needs of these at-risk patients should therefore be a priority for both research and policy. Copyright © 2014. Published by Elsevier Ltd.

Coping with treatment-related stress: effects on patient adherence in hemodialysis.

PubMed

Christensen, A J; Benotsch, E G; Wiebe, J S; Lawton, W J

1995-06-01

With a modified version of the Ways of Coping Checklist, the relation of coping to adherence among 57 hemodialysis patients was examined. The association of a particular type of coping to adherence was predicted to depend on the specific type of stressful encounter being considered. As predicted, coping efforts involving planful problem solving were associated with more favorable adherence when used in response to stressors involving a relatively controllable aspect of the hemodialysis context. For less controllable stressors, coping efforts involving emotional self-control were associated with more favorable adherence. The seeking of informational support in response to an uncontrollable encounter was associated with poorer fluid-intake adherence. Confrontive coping was associated with poorer adherence for both high- and low-control situations.

Trichomonas vaginalis clinical isolates: cytoadherence and adherence to polystyrene, intrauterine device, and vaginal ring.

PubMed

Dos Santos, Odelta; Rigo, Graziela Vargas; Macedo, Alexandre José; Tasca, Tiana

2017-12-01

The parasitism by Trichomonas vaginalis is complex and in part is mediated by cytoadherence accomplished via five surface proteins named adhesins and a glycoconjugate called lipophosphoglycan (TvLPG). In this study, we evaluated the ability of T. vaginalis isolates to adhere to cells, plastic (polystyrene microplates), intrauterine device (IUD), and vaginal ring. Of 32 T. vaginalis isolates, 4 (12.5%) were strong adherent. The T. vaginalis isolates TV-LACM6 and TV-LACM14 (strong polystyrene-adherent) were also able to adhere to IUD and vaginal ring. Following chemical treatments, results demonstrated that the T. vaginalis components, lipophosphoglycan, cytoskeletal proteins, and surface molecules, were involved in both adherence to polystyrene and cytoadherence. The gene expression level from four adhesion proteins was highest in trophozoites adhered to cells than trophozoites adhered to the abiotic surface (polystyrene microplate). Our data indicate the major involvement of TvLPG in adherence to polystyrene, and that adhesins are important for cytoadherence. Furthermore, to our knowledge, this is the first report showing the T. vaginalis adherence to contraceptive devices, reaffirming its importance as pathogen among women in reproductive age.

Striated Acto-Myosin Fibers Can Reorganize and Register in Response to Elastic Interactions with the Matrix

PubMed Central

Friedrich, Benjamin M.; Buxboim, Amnon; Discher, Dennis E.; Safran, Samuel A.

2011-01-01

The remarkable striation of muscle has fascinated many for centuries. In developing muscle cells, as well as in many adherent, nonmuscle cell types, striated, stress fiberlike structures with sarcomere-periodicity tend to register: Based on several studies, neighboring, parallel fibers at the basal membrane of cultured cells establish registry of their respective periodic sarcomeric architecture, but, to our knowledge, the mechanism has not yet been identified. Here, we propose for cells plated on an elastic substrate or adhered to a neighboring cell, that acto-myosin contractility in striated fibers close to the basal membrane induces substrate strain that gives rise to an elastic interaction between neighboring striated fibers, which in turn favors interfiber registry. Our physical theory predicts a dependence of interfiber registry on externally controllable elastic properties of the substrate. In developing muscle cells, registry of striated fibers (premyofibrils and nascent myofibrils) has been suggested as one major pathway of myofibrillogenesis, where it precedes the fusion of neighboring fibers. This suggests a mechanical basis for the optimal myofibrillogenesis on muscle-mimetic elastic substrates that was recently observed by several groups in cultures of mouse-, human-, and chick-derived muscle cells. PMID:21641316

Soluble fibrin augments platelet/tumor cell adherence in vitro and in vivo, and enhances experimental metastasis.

PubMed

Biggerstaff, J P; Seth, N; Amirkhosravi, A; Amaya, M; Fogarty, S; Meyer, T V; Siddiqui, F; Francis, J L

1999-01-01

There is considerable evidence for a relationship between hemostasis and malignancy. Since platelet adhesion to tumor cells has been implicated in the metastatic process and plasma levels of fibrinogen (Fg) and soluble fibrin (sFn) monomer are increased in cancer, we hypothesized that these molecules might enhance tumor-platelet interaction. We therefore studied binding of sFn monomer to tumor cells in a static microplate adhesion assay and determined the effect of pre-treating tumor cells with sFn on tumor cell-induced thrombocytopenia and experimental metastasis. Soluble fibrin (produced by adding thrombin to FXIII- and plasminogen-free Fg in the presence of Gly-Pro-Arg-Pro-amide (GPRP-NH2) significantly increased platelet adherence to tumor cells. This effect was primarily mediated by the integrins alphaIIb beta3 on the platelet and CD 54 (ICAM-1) on the tumor cells. Platelets adhered to untreated A375 cells (28 +/- 8 platelets/tumor cell) and this was not significantly affected by pre-treatment of the tumor cells with fibrinogen or GPRP-NH2. Although thrombin treatment increased adherence, pre-incubation of the tumor cells with sFn resulted in a further increase in platelet binding to tumor cells. In contrast to untreated tumor cells, intravenous injection of sFn-treated A 375 cells reduced the platelet count in anticoagulated mice, supporting the in vitro finding that sFn enhanced tumor cell-platelet adherence. In a more aggressive model of experimental metastasis, treating tumor cells with sFn enhanced lung seeding by 65% compared to untreated cells. Extrapolation of our data to the clinical situation suggests that coagulation activation, and subsequent increase in circulating Fn monomer, may enhance platelet adhesion to circulating tumor cells and thereby facilitate metastatic spread.

S-carboxymethylcysteine inhibits adherence of Streptococcus pneumoniae to human alveolar epithelial cells.

PubMed

Sumitomo, Tomoko; Nakata, Masanobu; Yamaguchi, Masaya; Terao, Yutaka; Kawabata, Shigetada

2012-01-01

Streptococcus pneumoniae is a major pathogen of respiratory infections that utilizes platelet-activating factor receptor (PAFR) for firm adherence to host cells. The mucolytic agent S-carboxymethylcysteine (S-CMC) has been shown to exert inhibitory effects against infection by several respiratory pathogens including S. pneumoniae in vitro and in vivo. Moreover, clinical studies have implicated the benefits of S-CMC in preventing exacerbation of chronic obstructive pulmonary disease, which is considered to be related to respiratory infections. In this study, to assess whether the potency of S-CMC is attributable to inhibition of pneumococcal adherence to host cells, an alveolar epithelial cell line stimulated with interleukin-1α was used as a model of inflamed epithelial cells. Despite upregulation of PAFR by inflammatory activation, treatment with S-CMC efficiently inhibited pneumococcal adherence to host epithelial cells. In order to gain insight into the inhibitory mechanism, the effects of S-CMC on PAFR expression were also investigated. Following treatment with S-CMC, PAFR expression was reduced at both mRNA and post-transcriptional levels. Interestingly, S-CMC was also effective in inhibiting pneumococcal adherence to cells transfected with PAFR small interfering RNAs. These results indicate S-CMC as a probable inhibitor targeting numerous epithelial receptors that interact with S. pneumoniae.

The effect of RU 486 and related compounds on cultured macrophage differentiation and function.

PubMed

Roberts, C P; Murphy, A A; Santanam, N; Parthasarathy, S

1996-08-01

Our purpose was to examine RU 486 and related compounds on macrophage scavenger receptors and cellular adhesion. THP-1 cells were activated with phorbol myristate acetate and treated with dexamethasone, levonorgestrel, and RU 486 alone or in combination. Scavenger receptor activity was determined by counting adhered cells. In addition, fluorescently labeled acetyl low density lipoprotein uptake was determined. Both dexamethasone and RU 486 significantly decreased activated macrophages (81% and 26% of control). Levonorgestrel stimulated adherent cells in activated monocytes (130% of control). RU 486 and dexamethasone were antagonistic when combined (p < 0.001). In contrast, dexamethasone could not overcome the stimulatory effect of levonorgestrel (p < 0.001). Fluorescent studies yielded similar results. RU 486 is a known antiglucocorticoid with novel antioxidant properties. Levonorgestrel has antiglucocorticoid but no antioxidant activity. Glucocorticoids decrease scavenger receptors and antioxidants regulate inflammatory cytokines. RU 486 antagonized the inhibitory effect of dexamethasone on scavenger receptors, whereas levonorgestrel was stimulatory. It is therapeutically important to up-regulate scavenger receptor activity by antiglucocorticoids in the peritoneal cavity of women with endometriosis. However, because these mechanisms also induce inflammatory cytokines, a balance of antioxidants and antiglucocorticoids may prove beneficial.

[Cytocompatibility of two porous bioactive glass-ceramic in vitro].

PubMed

Zhang, Yan; Jiang, Xinquan; Zhang, Xiuli; Wang, Deping; Zhen, Lei

2013-06-01

To compare the cytocompatibility of two kinds porous bioactive glass-ceramic made by same raw materials. Apatite/wollastonite bioactive glass-ceramic (4006) were prepared by sol-gel method, and bioactive glass (45S5) were prepared by melting method. Bone marrow stromal cells (BMSCs) were cultivated, differentiated and proliferated into osteoblasts, from a rabbit's marrow in the differentiatiofn culture medium with active function. The viability of BMSCs cultivated with extraction of these two kinds of biomaterial, which could represent the cytotoxicity effect of 4006 and 45S5 against BMSCs, was evaluated by the MTp assay. BMSCs were seeded and cocultivated with two kinds of biomaterial scaffolds respectively in vitro. The proliferation and biological properties of cells adhered to scaffolds were observed by inverted phase contrast microscope, scanning electron microscope (SEM), and environmental scanning electron microscope (ESEM), and a suitable cell amount for seeding on the scaffold was searched. There was no difference on the viability of BMSCs only cultured for one day by complete extract of 4006 and culture medium (P>0.05), but there was significant difference between them when the cells had been cultured for 3 days(P<0.01). The extract of 45S5 had significantly higher cytotoxicity than extract of culture medium (P<0.01). The BMSCs adhered, spread, and proliferated throughout the pores of the scaffold 4006, and the amount of cells adhered to 4006 was more than to 45S5. The adhered cells to 4006 increased with the rising amount of cells seeded. And 2 x 10(7) cells.mL-1 suspension resulted inthe highest cell adherence during the comparative cells adherence test. Apatite/woolastonite bioac tive glass-ceramic has good bioactivity and cytocompatibility. Therefore, it may have the potential to be a new cell vehicle for bone tissue engineering. And the suitable seeding cell amount of apatite/wollastonite bioactive glass-ceramic should be 2x10(7) cells.mL-1 or even more than that.

Distress and Diabetes Treatment Adherence: A Mediating Role for Perceived Control

PubMed Central

Gonzalez, Jeffrey S.; Shreck, Erica; Psaros, Christina; Safren, Steven A.

2014-01-01

Objective To understand independent pathways linking emotional distress, medication adherence and glycemic control in adults with type 2 diabetes, as well as the potential mediating effects of perceived control over illness and self-efficacy. Methods Adults with type 2 diabetes (N = 142) were recruited for an intervention study evaluating cognitive behavioral therapy for adherence and depression. Depressive symptom severity was assessed via semi-structured interview. Validated self-reports assessed diabetes-related distress, perceived control over diabetes (perceived control), self-efficacy for diabetes self-management and medication adherence. Glycemic control was evaluated by hemoglobin A1c (A1C). Only baseline data were included in correlational and linear regression analyses. Results Perceived control was an important mediator for both medication adherence and A1C outcomes. Specifically, regression analyses demonstrated that diabetes distress, but not depression severity, was significantly related to medication adherence and A1C. Self-efficacy and perceived control were also independently associated with medication adherence and A1C. Mediation analyses demonstrated a significant indirect effect for diabetes distress and medication adherence, through perceived control and self-efficacy. The relationship between distress and A1C was accounted for by an indirect effect through perceived control. Conclusion Results demonstrate that diabetes-related emotional distress is associated with poorer treatment adherence and glycemic control among adults with type 2 diabetes; these relationships were partially mediated through perceived control over diabetes. Perceptions of one’s personal ability to influence diabetes may be important in understanding the pathway between emotional distress and poor diabetes treatment outcomes. PMID:25110840

The effect of reminder systems on patients’ adherence to treatment

PubMed Central

Fenerty, Sarah D; West, Cameron; Davis, Scott A; Kaplan, Sebastian G; Feldman, Steven R

2012-01-01

Background Patient adherence is an important component of the treatment of chronic disease. An understanding of patient adherence and its modulating factors is necessary to correctly interpret treatment efficacy and barriers to therapeutic success. Purpose This meta-analysis aims to systematically review published randomized controlled trials of reminder interventions to assist patient adherence to prescribed medications. Methods A Medline search was performed for randomized controlled trials published between 1968 and June 2011, which studied the effect of reminder-based interventions on adherence to self-administered daily medications. Results Eleven published randomized controlled trials were found between 1999 and 2009 which measured adherence to a daily medication in a group receiving reminder interventions compared to controls receiving no reminders. Medication adherence was measured as the number of doses taken compared to the number prescribed within a set period of time. Meta- analysis showed a statistically significant increase in adherence in groups receiving a reminder intervention compared to controls (66.61% versus 54.71%, 95% CI for mean: 0.8% to 22.4%). Self-reported and electronically monitored adherence rates did not significantly differ (68.04% versus 63.67%, P = 1.0). Eight of eleven studies showed a statistically significant increase in adherence for at least one of the reminder group arms compared to the control groups receiving no reminder intervention. Limitations The data are limited by imperfect measures of adherence due to variability in data collection methods. It is also likely that concomitant educational efforts in the study populations, such as instructions regarding proper administration and importance of correct dosing schedules, contributed to improved patient adherence, both in reminder and control arms. The search strategy could have missed relevant studies which were categorized by disease rather than adherence. Conclusions Reminder-based interventions may improve adherence to daily medications. However, the interventions used in these studies, which included reminder phone calls, text messages, pagers, interactive voice response systems, videotelephone calls, and programmed electronic audiovisual reminder devices, are impractical for widespread implementation, and their efficacy may be optimized when combined with alternative adherence-modifying strategies. More practical reminder-based interventions should be assessed to determine their value in improving patient adherence and treatment outcomes. PMID:22379363

Identification of PblB mediating galactose-specific adhesion in a successful Streptococcus pneumoniae clone

PubMed Central

Hsieh, Yu-Chia; Lin, Tzu-Lung; Lin, Che-Ming; Wang, Jin-Town

2015-01-01

The pneumococcal genome is variable and there are minimal data on the influence of the accessory genome on phenotype. Pneumococcal serotype 14 sequence type (ST) 46 had been the most prevalent clone causing pneumonia in children in Taiwan. A microarray was constructed using the genomic DNA of a clinical strain (NTUH-P15) of serotype 14 ST46. Using DNA hybridization, genomic variations in NTUH-P15 were compared to those of 3 control strains. Microarray analysis identified 7 genomic regions that had significant increases in hybridization signals in the NTUH-P15 strain compared to control strains. One of these regions encoded PblB, a phage-encoded virulence factor implicated (in Streptococcus mitis) in infective endocarditis. The isogenic pblB mutant decreased adherence to A549 human lung epithelial cell compared to wild-type NTUH-P15 strain (P = 0.01). Complementation with pblB restored the adherence. PblB is predicted to contain a galactose-binding domain-like region. Preincubation of NTUH-P15 with D-galactose resulted in decreases of adherence to A549 cell in a dose-dependent manner. Challenge of mice with NTUH-P15, isogenic pblB mutant and pblB complementation strains determined that PblB was required for bacterial persistence in the nasopharynx and lung. PblB, as an adhesin mediating the galactose-specific adhesion activity of pneumococci, promote pneumococcal clonal success. PMID:26193794

‘Living cantilever arrays’ for characterization of mass of single live cells in fluids†

PubMed Central

Park, Kidong; Jang, Jaesung; Irimia, Daniel; Sturgis, Jennifer; Lee, James; Robinson, J. Paul; Toner, Mehmet; Bashir, Rashid

2013-01-01

The size of a cell is a fundamental physiological property and is closely regulated by various environmental and genetic factors. Optical or confocal microscopy can be used to measure the dimensions of adherent cells, and Coulter counter or flow cytometry (forward scattering light intensity) can be used to estimate the volume of single cells in a flow. Although these methods could be used to obtain the mass of single live cells, no method suitable for directly measuring the mass of single adherent cells without detaching them from the surface is currently available. We report the design, fabrication, and testing of ‘living cantilever arrays’, an approach to measure the mass of single adherent live cells in fluid using silicon cantilever mass sensor. HeLa cells were injected into microfluidic channels with a linear array of functionalized silicon cantilevers and the cells were subsequently captured on the cantilevers with positive dielectrophoresis. The captured cells were then cultured on the cantilevers in a microfluidic environment and the resonant frequencies of the cantilevers were measured. The mass of a single HeLa cell was extracted from the resonance frequency shift of the cantilever and was found to be close to the mass value calculated from the cell density from the literature and the cell volume obtained from confocal microscopy. This approach can provide a new method for mass measurement of a single adherent cell in its physiological condition in a non-invasive manner, as well as optical observations of the same cell. We believe this technology would be very valuable for single cell time-course studies of adherent live cells. PMID:18584076

Illness and treatment perceptions are associated with adherence to medications, diet, and exercise in diabetic patients.

PubMed

Broadbent, Elizabeth; Donkin, Liesje; Stroh, Julia C

2011-02-01

To investigate diabetic patients' perceptions of illness and treatments, and explore relationships to adherence and blood glucose control. Forty-nine type 1 and one hundred and eight type 2 diabetic patients completed questionnaires assessing illness perceptions, treatment beliefs, and adherence to medications, diet, and exercise. Blood glucose control was assessed from blood tests. Patients rated medication more important than diet and exercise, and reported higher adherence to medications. Insulin was perceived as more helpful for diabetes, while antihypertensives and cholesterol medication were perceived more helpful for preventing heart problems. Perceptions were associated with adherence to insulin, cholesterol and antihypertensive medications, exercise, and diet. Blood glucose control in type 1 diabetic patients was associated with insulin adherence and perceived personal control, and in type 2 diabetic patients to being prescribed insulin or antihypertensives, and perceived personal control. Patients hold specific mental models about diabetes treatments, which are associated with adherence.

Is patient empowerment the key to promote adherence? A systematic review of the relationship between self-efficacy, health locus of control and medication adherence.

PubMed

Náfrádi, Lilla; Nakamoto, Kent; Schulz, Peter J

2017-01-01

Current health policies emphasize the need for an equitable doctor-patient relationship, and this requires a certain level of patient empowerment. However, a systematic review of the empirical evidence on how empowerment affects medication adherence-the extent to which patients follow the physician's prescription of medication intake-is still missing. The goal of this systematic review is to sum up current state-of-the-art knowledge concerning the relationship between patient empowerment and medication adherence across medical conditions. As our conceptualization defines health locus of control and self-efficacy as being crucial components of empowerment, we explored the relationship between these two constructs and medication adherence. Relevant studies were retrieved through a comprehensive search of Medline and PsychINFO databases (1967 to 2017). In total, 4903 publications were identified. After applying inclusion and exclusion criteria and quality assessment, 154 articles were deemed relevant. Peer-reviewed articles, written in English, addressing the relationship between empowerment (predictor) and medication adherence (outcome) were included. High levels of self-efficacy and Internal Health Locus of Control are consistently found to promote medication adherence. External control dimensions were found to have mainly negative (Chance and God attributed control beliefs) or ambiguous (Powerful others attributed control beliefs) links to adherence, except for Doctor Health Locus of Control which had a positive association with medication adherence. To fully capture how health locus of control dimensions influence medication adherence, the interaction between the sub-dimensions and the attitudinal symmetry between the doctor and patient, regarding the patient's control over the disease management, can provide promising new alternatives. The beneficial effect of patients' high internal and concurrent physician-attributed control beliefs suggests that a so-called "joint empowerment" approach can be suitable in order to foster medication adherence, enabling us to address the question of control as a versatile component in the doctor-patient relationship.

Dissecting Seed Mucilage Adherence Mediated by FEI2 and SOS5

PubMed Central

Griffiths, Jonathan S.; Crepeau, Marie-Jeanne; Ralet, Marie-Christine; Seifert, Georg J.; North, Helen M.

2016-01-01

The plant cell wall is held together by the interactions between four major components: cellulose, pectin, hemicellulose, and proteins. Mucilage is a powerful model system to study the interactions between these components as it is formed of polysaccharides that are deposited in the apoplast of seed coat epidermal cells during seed development. When seeds are hydrated, these polysaccharides expand rapidly out of the apoplastic pocket, and form an adherent halo of mucilage around the seed. In Arabidopsis, mutations in multiple genes have similar loss of mucilage adherence phenotypes including CELLULOSE SYNTHASE 5 (CESA5)/MUCILAGE-MODIFIED 3 (MUM3), MUM5/MUCI21, SALT-OVERLY SENSITIVE 5 (SOS5), and FEI2. Here, we examine the interactions between these factors to better understand how they participate to control mucilage adherence. Double mutant phenotypes indicated that MUM5 and CESA5 function in a common mechanism that adheres pectin to the seed through the biosynthesis of cellulose and xylan, whereas SOS5 and FEI2, encoding a fasciclin-like arabinogalactan protein or a receptor-like kinase, respectively, function through an independent pathway. Cytological analyses of mucilage indicates that heteromannans are associated with cellulose, and not in the pathway involving SOS5 or FEI2. A SOS5 fluorescent protein fusion (SOS5-mCITRINE) was localized throughout the mucilage pocket, consistent with a structural role in pectin adhesion. The relationship between SOS5 and FEI2 mediated mucilage adherence was examined in more detail and while sos5 and fei2 mutants show similar phenotypes, key differences in the macromolecular characteristics and amounts of mucilage polymers were observed. FEI2 thus appears to have additional, as well as overlapping functions, with SOS5. Given that FEI2 is required for SOS5 function, we propose that FEI2 serves to localize SOS5 at the plasma membrane where it establishes interactions with mucilage polysaccharides, notably pectins, required for mucilage adherence prior to SOS5 being released into the apoplast. PMID:27524986

Impact of a pharmaceutical care program on clinical evolution and antiretroviral treatment adherence: a 5-year study

PubMed Central

Arroyo, María Jesús Hernández; Figueroa, Salvador Enrique Cabrera; Correa, Rosa Sepúlveda; de la Paz Valverde Merino, María; Gómez, Alicia Iglesias; Hurlé, Alfonso Domínguez-Gil

2013-01-01

Background Antiretroviral treatments (ART) form the basis of adequate clinical control in human immunodeficiency virus-infected patients, and adherence plays a primary role in the grade and duration of the antiviral response. The objectives of this study are: (1) to determine the impact of the implementation of a pharmaceutical care program on improvement of ART adherence and on the immunovirological response of the patients; and (2) to detect possible correlations between different adherence evaluation measurements. Methods A 60-month long retrospective study was conducted. Adherence measures used were: therapeutic drug monitoring, a simplified medication adherence questionnaire, and antiretroviral dispensation records (DR). The number of interviews and interventions related to adherence made for each patient in yearly periods was related to the changes in the adherence variable (measured with DR) in these same yearly periods. The dates when the laboratory tests were drawn were grouped according to proximity with the study assessment periods (February–May, 2005–2010). Results A total of 528 patients were included in the study. A significant relationship was observed between the simplified medication adherence questionnaire and DR over the 60-month study period (P < 0.01). Improvement was observed in the mean adherence level (P < 0.001), and there was a considerable decrease in the percentage of patients with CD4+ lymphocytes less than 200 cells/mm3 (P < 0.001). A relationship was found between the number of patients with optimum adherence levels and the time that plasma viral load remained undetected. The number of interviews and interventions performed in each patient in the first 12 months from the onset of the pharmaceutical care program (month 6), was related to a significant increase in adherence during this same time period. Conclusion The results suggest that the establishment and permanence of a pharmaceutical care program may increase ART adherence, increase permanence time of the patient with undetectable plasma viral loads, and improve patients’ lymphocyte count. PMID:23983457

Joint longitudinal data analysis in detecting determinants of CD4 cell count change and adherence to highly active antiretroviral therapy at Felege Hiwot Teaching and Specialized Hospital, North-west Ethiopia (Amhara Region).

PubMed

Seyoum, Awoke; Ndlovu, Principal; Temesgen, Zewotir

2017-03-16

Adherence and CD4 cell count change measure the progression of the disease in HIV patients after the commencement of HAART. Lack of information about associated factors on adherence to HAART and CD4 cell count reduction is a challenge for the improvement of cells in HIV positive adults. The main objective of adopting joint modeling was to compare separate and joint models of longitudinal repeated measures in identifying long-term predictors of the two longitudinal outcomes: CD4 cell count and adherence to HAART. A longitudinal retrospective cohort study was conducted to examine the joint predictors of CD4 cell count change and adherence to HAART among HIV adult patients enrolled in the first 10 months of the year 2008 and followed-up to June 2012. Joint model was employed to determine joint predictors of two longitudinal response variables over time. Furthermore, the generalized linear mixed effect model had been used for specification of the marginal distribution, conditional to correlated random effect. A total of 792 adult HIV patients were studied to analyze the longitudinal joint model study. The result from this investigation revealed that age, weight, baseline CD4 cell count, ownership of cell phone, visiting times, marital status, residence area and level of disclosure of the disease to family members had significantly affected both outcomes. From the two-way interactions, time * owner of cell phone, time * sex, age * sex, age * level of education as well as time * level of education were significant for CD4 cell count change in the longitudinal data analysis. The multivariate joint model with linear predictor indicates that CD4 cell count change was positively correlated (p ≤ 0.0001) with adherence to HAART. Hence, as adherence to HAART increased, CD4 cell count also increased; and those patients who had significant CD4 cell count change at each visiting time had been encouraged to be good adherents. Joint model analysis was more parsimonious as compared to separate analysis, as it reduces type I error and subject-specific analysis improved its model fit. The joint model operates multivariate analysis simultaneously; and it has great power in parameter estimation. Developing joint model helps validate the observed correlation between the outcomes that have emerged from the association of intercepts. There should be a special attention and intervention for HIV positive adults, especially for those who had poor adherence and with low CD4 cell count change. The intervention may be important for pre-treatment counseling and awareness creation. The study also identified a group of patients who were with maximum risk of CD4 cell count change. It is suggested that this group of patients needs high intervention for counseling.

EVALUATING THE ROLE OF SDIA AND HHA IN ENHANCED ADHERENCE OF A SDIA HHA DOUBLE MUTANT OF ENTEROHEMORRHAGIC ESCHERICHIA COLI O157:H7

USDA-ARS?s Scientific Manuscript database

Adherence of Enterohemorrhagic Escherichia coli (EHEC) O157:H7 to biotic (epithelial cells) and abiotic surfaces (biofilm formation) proceeds from an initial reversible adherence to an irreversible stage of intimate adherence. While flagella and fimbriae facilitate initial stage of adherence in both...

Medication adherence and blood pressure control amongst adults with primary hypertension attending a tertiary hospital primary care clinic in Eastern Nigeria

PubMed Central

Ofoedu, John N.; Njoku, Patrick U.; Amadi, Agwu N.; Godswill-Uko, Ezinne U.

2013-01-01

Abstract Background As the case detection rates of hypertension increase in adult Nigerians, achieving target blood pressure (BP) control has become an important management challenge. Objectives To describe medication adherence and BP control amongst adult Nigerians with primary hypertension attending a primary care clinic of a tertiary hospital in a resource-poor environment in Eastern Nigeria. Methods A cross-sectional study was carried out in 140 adult patients with primary hypertension who have been on treatment for at least 6 months at the primary care clinic of Federal Medical Centre, Umuahia. A patient was said to have achieved goal BP control if the BP was < 140 per 90 mmHg. Adherence was assessed in the previous 30 days using a pretested researcher-administered questionnaire on 30 days of self-reported therapy. Adherence was graded using an ordinal scoring system of 0–4; an adherent patient was one who scored 4 points in the previous 30 days. Reasons for non-adherence were documented. Results Adherence to medication and BP control rates were 42.9% and 35.0% respectively. BP control was significantly associated with medication adherence (p = 0.03), antihypertensive medication duration ≥3 years (p = 0.042), and taking ≥ one form of antihypertensive medication (p = 0.04). BP at the recruitment visit was significantly higher than at the end of the study (p = 0.036). The most common reason for non-adherence was forgetfulness (p = 0.046). Conclusions The rate of BP control amongst the study population was low, which may be connected with low medication adherence. This study urges consideration of factors relating to adherence alongside other factors driving goal BP control.

Association between the 8-item Morisky Medication Adherence Scale (MMAS-8) and blood pressure control.

PubMed

Oliveira-Filho, Alfredo Dias; Barreto-Filho, José Augusto; Neves, Sabrina Joany Felizardo; Lyra Junior, Divaldo Pereira de

2012-07-01

Non-adherence to treatment is an important and often unrecognized risk factor that contributes to reduced control of blood pressure (BP). To determine the association between treatment adherence measured by a validated version in Portuguese of the 8-item Morisky Medication Adherence Scale (MMAS-8) and BP control in hypertensive outpatients. A cross-sectional study was carried out with hypertensive patients older than 18 years, treated at six of the Family Health Strategy Units in Maceió (AL), through interviews and home blood pressure measurements, between January and April 2011. Adherence was determined by MMAS-8 version translated for this study. The patients were considered adherent when they had a score equal to 8 at the MMAS-8. The prevalence of adherence among the 223 patients studied was 19.7%, while 34% had controlled BP (> 140/90 mmHg). The average adherence value according to the MMAS-8 was 5.8 (± 1.8). Adherent patients showed to be more prone (OR = 6.1, CI [95%] = 3.0 to 12.0) to have blood pressure control than those who reached mean (6 to <8) or low values (<6) at the adherence score. The Portuguese version of MMAS-8 was showed a significant association with BP control (p = 0.000). The diagnosis of non-adherent behavior through the application of MMAS-8 in patients using of antihypertensive medications was predictive of elevated systolic and diastolic BP.

Interference in adhesion of bacteria and yeasts isolated from explanted voice prostheses to silicone rubber by rhamnolipid biosurfactants.

PubMed

Rodrigues, L R; Banat, I M; van der Mei, H C; Teixeira, J A; Oliveira, R

2006-03-01

The effects and extent of adhesion of four different bacterial and two yeast strains isolated from explanted voice prostheses to silicone rubber with and without an adsorbed rhamnolipid biosurfactant layer obtained from Pseudomonasaeruginosa DS10-129 was studied. The ability of rhamnolipid biosurfactant to inhibit adhesion of micro-organisms to silicone rubber was investigated in a parallel-plate flow chamber. The anti-adhesive activity of the biosurfactant at different concentrations was significant against all the strains and depended on the micro-organism tested. The results showed an effective reduction in the initial deposition rates, and the number of bacterial cells adhering after 4 h, for all micro-organisms tested at the 4 g l(-1) undiluted rhamnolipid solution. Maximum initial reduction of adhesion rate (an average of 66%) occurred for Streptococcus salivarius GB 24/9 and Candida tropicalis GB 9/9. The number of cells adhering after 4 h on silicone rubber conditioned with biosurfactant was reduced to 48% for Staphylococcus epidermidis GB 9/6, Strep. salivarius GB 24/9, Staphylococcus aureus GB 2/1 and C. tropicalis GB 9/9 in comparison to controls. Perfusing the flow chamber with biosurfactant containing solution followed by the passage of a liquid-air interface, to investigate detachment of micro-organisms adhering to silicone rubber, produced high detachment (96%) of adhered cells for all micro-organisms studied, except for Staph. aureus GB 2/1 (67%). It is concluded that biosurfactant represent suitable compounds that should be considered in developing future strategies to prevent the microbial colonization of silicone rubber voice prostheses.

Factors associated with non-adherence to antiretroviral therapy in adults with AIDS in the first six months of treatment in Salvador, Bahia State, Brazil.

PubMed

Silva, José Adriano Góes; Dourado, Inês; Brito, Ana Maria de; Silva, Carlos Alberto Lima da

2015-06-01

The control of viral replication is essential in the highly active antiretroviral therapy (HAART), and adherence to therapy is instrumental for such control. Individual and external factors influence adhesion to the use of antiretroviral (ARV) drugs. This is a cross-sectional study to investigate factors associated with non-adherence to HAART in AIDS patients in Salvador, Bahia State, Brazil, with age ≥ 13 years and first prescription in 2009. Data was collected from patient charts and pharmacy records. From a total of 216 patients, 65.3% were males; mean age 37.8 ± 9.5 years; single, 67.9%; heterosexual, 64%; more than 8 years of school education, 65.3%; alcohol users, 61.5%; non-smokers, 75,1% or non-illicit drug users, 93.7%. A proportion of 94% started ARV therapy with TCD4+ < 350 cells/mm3; 61.8% were symptomatic; and 68.4% had an adverse drug reaction. The prevalence of non-adherence was 25%. The variables associated were: longer time between HIV infection and AIDS (aOR = 3.9), adverse drug reaction (aOR = 2.4), under 34 years of age (aOR = 2.2), less than 8 years of school education (aOR = 2.2) and illicit drugs use (aOR = 2.6). A high-non-adherence rate is an important problem within the first six months of HAART.

An evaluation of bacterial contamination of barriers used in periapical tissue regeneration: Part 1--Bacterial adherence.

PubMed

Sharma, Priya; Mickel, André K; Chogle, Sami; Sharma, Prem Nath; Han, Yiping W; Jones, Jefferson J

2008-02-01

To compare the adherence of Prevotella melaninogenica and Enterococcus faecalis to 3 guided tissue regeneration membranes: Atrisorb, Lambone, and OsseoQuest. It was hypothesized that OsseoQuest would show increased bacterial adherence compared to Lambone and Atrisorb. The barriers were suspended in trypticase soy broth containing an inoculum of either P melaninogenica or E faecalis. The samples were incubated under appropriate conditions for 6, 24, and 48 hours. Following incubation, each membrane was mixed in fresh media in a vortex machine to dislodge adherent bacteria. The vortexed media was quantitatively assessed using serial dilutions for viable cell count. E faecalis exhibited higher adherence compared to P melaninogenica with time. Of the membranes tested, Lambone displayed the least bacterial adherence. An analysis of the results indicated that bacterial adherence was time-dependent for all membranes. Membrane structure, chemical configuration, hydrophobicity, and bacterial cell surface structure were suggested as factors contributing to variance in bacterial adherence.

Contributions of EspA Filaments and Curli Fimbriae in Cellular Adherence and Biofilm Formation of Enterohemorrhagic Escherichia coli O157:H7

PubMed Central

Sharma, Vijay K.; Kudva, Indira T.; Bearson, Bradley L.; Stasko, Judith A.

2016-01-01

In Escherichia coli O157:H7 (O157), the filamentous structure of the type III secretion system is produced from the polymerization of the EspA protein. EspA filaments are essential for O157 adherence to epithelial cells. In previous studies, we demonstrated that O157 hha deletion mutants showed increased adherence to HEp-2 cells and produced abundant biofilms. Transcriptional analysis revealed increased expression of espA as well as the csgA gene, which encodes curli fimbriae that are essential for biofilm formation. In the present study, we constructed hha espA, hha csgA, and hha csgA espA deletion mutants to determine the relative importance of EspA and CsgA in O157 adherence to HEp-2 cells and biofilm formation. In vitro adherence assays, conducted at 37°C in a tissue culture medium containing 0.1% glucose, showed that HEp-2 cell adherence required EspA because hha espA and hha csgA espA mutants adhered to HEp-2 cells at higher levels only when complemented with an espA-expressing plasmid. Biofilm assays performed at 28°C in a medium lacking glucose showed dependency of biofilm formation on CsgA; however EspA was not produced under these conditions. Despite production of detectable levels of EspA at 37°C in media supplemented with 0.1% glucose, the biofilm formation occurred independent of EspA. These results indicate dependency of O157 adherence to epithelial cells on EspA filaments, while CsgA promoted biofilm formation under conditions mimicking those found in the environment (low temperature with nutrient limitations) and in the digestive tract of an host animal (higher temperature and low levels of glucose). PMID:26900701

Adherence and retention in clinical trials: a community-based approach.

PubMed

Fouad, Mona N; Johnson, Rhoda E; Nagy, M Christine; Person, Sharina D; Partridge, Edward E

2014-04-01

The Community Health Advisor (CHA) model has been widely used to recruit rural and low-income, mostly African American women into clinical and behavioral research studies. However, little is known about its effectiveness in promoting retention and adherence of such women in clinical trials. The Community-Based Retention Intervention Study evaluated the effectiveness of a community-based intervention strategy using the CHA model and the empowerment theory to improve the retention and adherence of minority and low-income women in clinical trials. The research strategy included the training and use of the volunteer CHAs as research partners. The target population included women participating in the University of Alabama at Birmingham clinical site of the Atypical Squamous Cells of Undetermined Significance-Low-Grade Squamous Intraepithelial Lesion (ASCUS-LSIL) Triage Study (ALTS), a multicenter, randomized clinical trial. Two communities in Jefferson County, Alabama, that were matched according to population demographics were identified and randomly assigned to either an intervention group or a control group. Thirty community volunteers were recruited to be CHAs and to implement the intervention with the ALTS trial participants. In total, 632 ALTS participants agreed to participate in the project, including 359 in the intervention group, which received CHA care, and 273 in the control group, which received standard care. Adherence rates for scheduled clinic visits were significantly higher in the intervention group (80%) compared with the control group (65%; P < .0001). The results indicate that volunteer CHAs can be trained to serve as research partners and can be effective in improving the retention and adherence of minority and low-income women in clinical trials. © 2014 American Cancer Society.

Quantitative characterization of mesenchymal stem cell adhesion to the articular cartilage surface.

PubMed

Hung, Ben P; Babalola, Omotunde M; Bonassar, Lawrence J

2013-12-01

There has been great interest in use of mesenchymal stem cell (MSC)-based therapies for cartilage repair. Most recently, treatments involving intra-articular injection of MSCs have shown great promise for cartilage repair and arthritis therapy, which rely on MSC adhesion to cartilage. While there is some information on chondrocyte adhesion to cartilage, there is relatively little known about the kinetics and strength of MSC adhesion to cartilage. The goals of this study were as follows: (1) to quantify the kinetics and strength of adhesion of marrow-derived MSCs to articular cartilage using standard laboratory hardware; (2) to compare this adhesion behavior to that of articular chondrocytes; and (3) to assess the effect of serial monolayer culture on MSC adhesion. First through fourth passage MSCs and primary articular chondrocytes were allowed to adhere to the articular surface of cartilage disks for up to 30 h and the number of adhered cells was recorded to quantify adhesion kinetics. After 30 h, adherent cells were subjected to centrifugal shear to determine adhesion strength, quantified as the shear necessary to detach half the adhered cells (σ50 ). The number of adhered MSCs and adhesion strength increased with passage number and MSCs adhered more strongly than did primary articular chondrocytes. As such, the kinetics and strength of MSC adhesion to cartilage is not dramatically lower than that for articular chondrocytes. This protocol for assessing cell adhesion to cartilage is simple to implement and may represent an important screening tool for assessing the efficacy of cell-based therapies for cartilage repair. Copyright © 2013 Wiley Periodicals, Inc., a Wiley Company.

Integrin expression by human osteoblasts cultured on degradable polymeric materials applicable for tissue engineered bone.

PubMed

El-Amin, Saadiq F; Attawia, Mohamed; Lu, Helen H; Shah, Asist K; Chang, Richard; Hickok, Noreen J; Tuan, Rocky S; Laurencin, Cato T

2002-01-01

The use of biodegradable polymers in the field of orthopaedic surgery has gained increased popularity, as surgical pins and screws, and as potential biological scaffolds for repairing cartilage and bone defects. One such group of polymers that has gained considerable attention are the polyesters, poly(lactide-co-glycolide) (PLAGA) and polylactic acid (PLA), because of their minimal tissue inflammatory response, favorable biocompatibility and degradation characteristics. The objective of this study was to evaluate human osteoblastic cell adherence and growth on PLAGA and PLA scaffolds by examining integrin receptor (alpha2, alpha3, alpha4, alpha5, alpha6 and beta1) expression. Primary human osteoblastic cells isolated from trabecular bone adhered efficiently to both PLAGA and PLA, with the rate of adherence on PLAGA comparable to that of control tissue culture polystyrene (TCPS), and significantly higher than on PLA polymers at 3, 6 and 12 h. Human osteoblastic phenotypic expression, alkaline phosphatase (ALP) activity was positive on both degradable matrices, whereas osteocalcin levels were significantly higher on cells grown on PLAGA than on PLA composites. Interestingly, the integrin subunits, alpha2, alpha3, alpha4, alpha5, alpha6 and beta1 were all expressed at higher levels by osteoblasts cultured on PLAGA than those on PLA as analyzed by westerns blots and by flow cytometry. Among the integrins, alpha2, beta5 and beta1 showed the greatest difference in levels between the two surfaces. Thus, both PLA and PLAGA support osteoblastic adhesion and its accompanying engagement of integrin receptor and expression of osteocalcin and ALP. However PLAGA consistently appeared to be a better substrate for osteoblastic cells based on these parameters. This study is one of the first to investigate the ability of primary human osteoblastic cells isolated from trabecular bone to adhere to the biodegradable polymers PLAGA and PLA, and to examine the expression of their key adhesion receptors (integrins) on these substrates.

In vitro adherence of Lactobacillus strains isolated from the vaginas of healthy Iranian women.

PubMed

Mousavi, Elham; Makvandi, Manoochehr; Teimoori, Ali; Ataei, Angila; Ghafari, Shokouh; Najafian, Mahin; Ourang, Ziba; Samarbaf-Zadeh, Alireza

2016-12-01

The lactobacilli are a part of the bacterial flora of the human vagina. Detection of normal Lactobacillus species in the vaginas of healthy women in different geographical locations, and evaluation of their specific properties, can aid in the selection of the best species for preventing sexually transmitted diseases in the future. This study was performed to isolate and identify the Lactobacillus species in the vaginas of healthy women and to evaluate the adherence of these lactobacilli to Vero and HeLa cell lines. The study included 100 women. Bacteria were isolated from healthy women and purified. Phenotypic and biochemical tests were performed to identify the lactobacilli. The Lactobacillus species were detected by molecular methods using polymerase chain reaction amplification of the full length of the 16S rDNA of the isolated bacteria. Several isolates of each species were then selected to study their adherence to Vero and HeLa cell lines. Among the 50 samples taken from healthy women meeting the inclusion criteria, Lactobacillus species were identified in 33 (66%) samples. Of these lactobacilli, 14 isolates were Lactobacillus crispatus, six (18.2%) were Lactobacillus gasseri, nine (27%) were Lactobacillus rhamnosus, and the rest were either Lactobacillus salivarius (6%) or Lactobacillus plantarum (6%). L. rhamnosus showed the greatest adhesion to the cells when compared to the other tested species. All the lactobacilli isolated in this study showed a smaller capacity for cell adherence when compared with control species. L. crispatus, L. rhamnosus, and L. gasseri were the dominant Lactobacillus species in the vaginas of healthy women in Iran. L. rhamnosus attached more readily to the cells than did the other species; therefore, this isolate is a good candidate for further studies on the potential health benefits and application of lactobacilli as probiotics. Copyright © 2016. Published by Elsevier Taiwan LLC.

Sacha Inchi Oil (Plukenetia volubilis L.), effect on adherence of Staphylococus aureus to human skin explant and keratinocytes in vitro.

PubMed

Gonzalez-Aspajo, German; Belkhelfa, Haouaria; Haddioui-Hbabi, Laïla; Bourdy, Geneviève; Deharo, Eric

2015-08-02

Plukenetia volubilis L. (Euphorbiaceae) is a domesticated vine distributed from the high-altitude Andean rain forest to the lowlands of the Peruvian Amazon. Oil from the cold-pressed seeds, sold under the commercial name of Sacha Inchi Oil (SIO) is actually much in favour because it contains a high percentage of omega 3 and omega 6, and is hence used as a dietary supplement. SIO is also used traditionally for skin care, in order to maintain skin softness, and for the treatment of wounds, insect bites and skin infections, in a tropical context where the skin is frequently damaged. This study was designed in order to verify whether the traditional use of SIO for skin care would have any impact on Staphylococcus aureus growth and skin adherence, as S. aureus is involved in many skin pathologies (impetigo, folliculitis, furuncles and subcutaneous abscesses) being one if the main pathogens that can be found on the skin. Therefore, our objective was to assess SIO bactericidal activity and interference with adherence to human skin explants and the keratinocyte cell line. Cytotoxicity on that cells was also determined. The activity of SIO was compared to coconut oil (CocO), which is widely used for skin care but has different unsaturated fatty acids contents. Laboratory testing with certified oil, determined antibacterial activity against radio labelled S. aureus. Cytotoxic effects were measured with XTT on keratinocyte cells and with neutral red on human skin explants; phenol was used as cytotoxic control. Adherence assays were carried out by mixing H3-labelled S. aureus bacteria with keratinocyte cells and human skin explants, incubated with oils 2h before (to determine the inhibition of adherence, assimilated to a preventive effect) or 2h after the contact of the biological material with S. aureus (to assess the detachment of the bacteria, assimilated to a curative effect). Residual radioactivity measured after washings made it possible to determine the adherence intensity. Bactericidal effect was determined by colony counting on trypticase soy agar. Laboratory assays showed that SIO and CocO, tested undiluted, were not cytotoxic on keratinocytes nor human explants and were not bactericidal neither. SIO was more active as antiadherent (preventive) than CocO on keratinocytes. There was no significant difference between detachment effects (curative) of both oils on keratinocytes but SIO was almost 5 times more active on the detachment of S. aureus from human skin explants. From that study it can be concluded that the use of SIO on dermal cells is safe and efficient in the inhibition of S. aureus adherence. Our results tend to support the traditional use of undiluted SIO in skin care. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Adhesion of Bacillus spores and Escherichia coli cells to inert surfaces: role of surface hydrophobicity.

PubMed

Faille, Christine; Jullien, Celine; Fontaine, Francoise; Bellon-Fontaine, Marie-Noelle; Slomianny, Christian; Benezech, Thierry

2002-08-01

The ability of bacterial spores and vegetative cells to adhere to inert surfaces was investigated by means of the number of adherent spores (Bacillus cereus and Bacillus subtilis spores) and Escherichia coli cells and their resistance to cleaning or rinsing procedures (adhesion strength). Six materials (glass, stainless steel, polyethylene high density (PEHD), polyamide-6, polyvinyl chloride, and Teflon) were tested. Slight differences in the number of adherent spores (less than 1 log unit) were observed between materials, but a higher number of adherent E. coli cells was found on the hydrophobic materials PEHD and Teflon. Conversely, the resistance of both B. cereus and B. subtilis spores to a cleaning procedure was significantly affected by the material. Hydrophobic materials were harder to clean. The topography parameter derived from the Abbott-Firestone curve, RVK, and, to a lesser extent, the widely used roughness parameters RA (average roughness) and Rz (maximal roughness), were related to the number of adherent cells. Lastly, the soiling level as well as the adhesion strength were shown to depend largely on the microorganism. The number of adhering B. cereus hydrophobic spores and their resistance to a cleaning procedure were found to be 10 times greater than those of the B. subtilis hydrophilic spores. Escherichia coli was loosely bound to all the materials tested, even after 24 h biofilm formation.

Optimization and inhibition of the adherent ability of Plasmodium falciparum-infected erythrocytes.

PubMed

Smith, H; Crandall, I; Prudhomme, J; Sherman, I W

1992-01-01

The vast majority of the 1-2 million malaria associated deaths that occur each year are due to anemia and cerebral malaria (the attachment of erythrocytes containing mature forms of Plasmodium falciparum to the endothelial cells that line the vascular beds of the brain). A "model system" for the study of cerebral malaria employs amelanotic melanoma cells as the "target" cells in an in vitro cytoadherence assay. Using this model system we determined that the optimum pH for adherence is 6.6 to 6.8, that high concentrations of Ca2+ (50mM) result in increased levels of binding, and that the type of buffer used influences adherence (Bis Tris > MOPS > HEPES > PIPES). We also observed that the ability of infected erythrocytes to cytoadhere varied from (erythrocyte) donor to donor. We have produced murine monoclonal antibodies against P. falciparum-infected red cells which recognize modified forms of human band 3; these inhibit the adherence of infected erythrocytes to melanoma cells in a dose-responsive fashion. Antimalarials (chloroquine, quinacrine, mefloquine, artemisinin), on the other hand, affected adherence in an indirect fashion i.e. since cytoadherence is due, in part, to the presence of knobs on the surface of the infected erythrocyte, and knob formation is dependent on intracellular parasite growth, when plasmodial development is inhibited so is knob production, and consequently adherence is ablated.

Ovarian carcinoma ascites spheroids adhere to extracellular matrix components and mesothelial cell monolayers.

PubMed

Burleson, Kathryn M; Casey, Rachael C; Skubitz, Keith M; Pambuccian, Stephan E; Oegema, Theodore R; Skubitz, Amy P N

2004-04-01

Ovarian carcinoma cells form multicellular aggregates, or spheroids, in the peritoneal cavity of patients with advanced disease. The current paradigm that ascites spheroids are non-adhesive leaves their contribution to ovarian carcinoma dissemination undefined. Here, spheroids obtained from ovarian carcinoma patients' ascites were characterized for their ability to adhere to molecules encountered in the peritoneal cavity, with the goal of establishing their potential to contribute to ovarian cancer spread. Spheroids were recovered from the ascites fluid of 11 patients with stage III or stage IV ovarian carcinoma. Adhesion assays to extracellular matrix (ECM) proteins and human mesothelial cell monolayers were performed for each of the ascites spheroid samples. Subsequently, inhibition assays were performed to identify the cell receptors involved. Most ascites samples adhered moderately to fibronectin and type I collagen, with reduced adhesion to type IV collagen and laminin. Monoclonal antibodies against the beta1 integrin subunit partially inhibited this adhesion. Ascites spheroids also adhered to hyaluronan. Additionally, spheroids adhered to live, but not fixed, human mesothelial cell monolayers, and this adhesion was partially mediated by beta1 integrins. The cellular content of the ascites fluid has often been considered non-adhesive, but our findings are the first to suggest that patient-derived ascites spheroids can adhere to mesothelial extracellular matrix via beta1 integrins, indicating that spheroids should not be ignored in the dissemination of ovarian cancer.

Workflow for high-content, individual cell quantification of fluorescent markers from universal microscope data, supported by open source software.

PubMed

Stockwell, Simon R; Mittnacht, Sibylle

2014-12-16

Advances in understanding the control mechanisms governing the behavior of cells in adherent mammalian tissue culture models are becoming increasingly dependent on modes of single-cell analysis. Methods which deliver composite data reflecting the mean values of biomarkers from cell populations risk losing subpopulation dynamics that reflect the heterogeneity of the studied biological system. In keeping with this, traditional approaches are being replaced by, or supported with, more sophisticated forms of cellular assay developed to allow assessment by high-content microscopy. These assays potentially generate large numbers of images of fluorescent biomarkers, which enabled by accompanying proprietary software packages, allows for multi-parametric measurements per cell. However, the relatively high capital costs and overspecialization of many of these devices have prevented their accessibility to many investigators. Described here is a universally applicable workflow for the quantification of multiple fluorescent marker intensities from specific subcellular regions of individual cells suitable for use with images from most fluorescent microscopes. Key to this workflow is the implementation of the freely available Cell Profiler software(1) to distinguish individual cells in these images, segment them into defined subcellular regions and deliver fluorescence marker intensity values specific to these regions. The extraction of individual cell intensity values from image data is the central purpose of this workflow and will be illustrated with the analysis of control data from a siRNA screen for G1 checkpoint regulators in adherent human cells. However, the workflow presented here can be applied to analysis of data from other means of cell perturbation (e.g., compound screens) and other forms of fluorescence based cellular markers and thus should be useful for a wide range of laboratories.

Lulo cell line derived from Lutzomyia longipalpis (Diptera: Psychodidae): a novel model to assay Leishmania spp. and vector interaction.

PubMed

Côrtes, Luzia Mc; Silva, Roger Mm; Pereira, Bernardo As; Guerra, Camila; Zapata, Angela C; Bello, Felio J; Finkelstein, Léa C; Madeira, Maria F; Brazil, Reginaldo P; Côrte-Real, Suzana; Alves, Carlos R

2011-11-14

Leishmania (Vianna) braziliensis, Leishmania (Leishmania) amazonensis and Leishmania (Leishmania) chagasi are important parasites in the scenario of leishmaniasis in Brazil. During the life cycle of these parasites, the promastigote forms adhere to the midgut epithelial microvillii of phlebotomine insects to avoid being secreted along with digestive products. Lulo cells are a potential model that will help to understand the features of this adhesion phenomenon. Here, we analyze the interaction between Leishmania spp. promastigotes and Lulo cells in vitro, specifically focusing on adhesion events occurring between three Leishmania species and this cell line. Confluent monolayers of Lulo cells were incubated with promastigotes and adhesion was assessed using both light microscopy and scanning electron microscopy. The results indicate that species from the subgenera Leishmania and Viannia have great potential to adhere to Lulo cells. The highest adherence rate was observed for L. (L.) chagasi after 24 h of incubation with Lulo cells (27.3 ± 1.8% of cells with adhered promastigotes), followed by L. (L.) amazonensis (16.0 ± 0.7%) and L. (V.) braziliensis (3.0 ± 0.7%), both after 48 h. In the ultrastructural analysis, promastigote adherence was also assessed by scanning electron microscopy, showing that, for parasites from both subgenera, adhesion occurs by both the body and the flagellum. The interaction of Lulo cells with Leishmania (L.) chagasi showed the participation of cytoplasmic projections from the former closely associating the parasites with the cells. We present evidence that Lulo cells can be useful in studies of insect-parasite interactions for Leishmania species.

Marker-free detection of progenitor cell differentiation by analysis of Brownian motion in micro-wells.

PubMed

Sekhavati, Farzad; Endele, Max; Rappl, Susanne; Marel, Anna-Kristina; Schroeder, Timm; Rädler, Joachim O

2015-02-01

The kinetics of stem and progenitor cell differentiation at the single-cell level provides essential clues to the complexity of the underlying decision-making circuits. In many hematopoietic progenitor cells, differentiation is accompanied by the expression of lineage-specific markers and by a transition from a non-adherent to an adherent state. Here, using the granulocyte-macrophage progenitor (GMP) as a model, we introduce a label-free approach that allows one to follow the course of this transition in hundreds of single cells in parallel. We trap single cells in patterned arrays of micro-wells and use phase-contrast time-lapse movies to distinguish non-adherent from adherent cells by an analysis of Brownian motion. This approach allowed us to observe the kinetics of induced differentiation of primary bone-marrow-derived GMPs into macrophages. The time lapse started 2 hours after addition of the cytokine M-CSF, and nearly 80% of the population had accomplished the transition within the first 20 h. The analysis of Brownian motion proved to be a sensitive and robust tool for monitoring the transition, and thus provides a high-throughput method for the study of cell differentiation at the single-cell level.

Plasmin on adherent cells: from microvesiculation to apoptosis

PubMed Central

Doeuvre, Loïc; Plawinski, Laurent; Goux, Didier; Vivien, Denis; Anglés-Cano, Eduardo

2010-01-01

SYNOPSIS Cell activation by stressors is characterised by a sequence of detectable phenotypic cell changes. The strength of a given stimulus induces modifications in the activity of membrane phospholipids transporters and calpains, which leads to phosphatidylserine exposure, membrane blebbing and the release of microparticles (nanoscale membrane vesicles). This vesiculation could be considered as a warning signal that may be followed, if the stimulus is maintained, by cell detachment-induced apoptosis. In this study, plasminogen incubated onto adherent cells is activated into plasmin by constitutively expressed tPA or uPA. Plasmin formed on the cellular membrane then induces an unique response characterized by membrane blebbing and vesiculation. Hitherto unknown for plasmin, these membrane changes are similar to those induced by thrombin on platelets. If plasmin formation evolves, matrix proteins are then degraded, cells lose attachment and enter the apoptotic process, characterized by DNA fragmentation and electron microscopy features. This sequence of events was experimentally documented at all these stages. Since other proteolytic or inflammatory stimuli may evoke similar responses by distinct adherent cells, this sequence can be applied to distinguish activated adherent cells from cells entering the apoptotic process. This is a major definition crucial to the identification of mediators, inhibitors and potential therapeutic agents. PMID:20846121

Measuring Mitochondrial Function in Permeabilized Cells Using the Seahorse XF Analyzer or a Clark-Type Oxygen Electrode.

PubMed

Divakaruni, Ajit S; Rogers, George W; Murphy, Anne N

2014-05-27

Measurements of mitochondrial respiration in intact cells can help define metabolism and its dysregulation in fields such as cancer, metabolic disease, immunology, and neurodegeneration. Although cells can be offered various substrates in the assay medium, many cell types can oxidize stored pools of energy substrates. A general bioenergetic profile can therefore be obtained using intact cells, but the inability to control substrate provision to the mitochondria can restrict an in-depth, mechanistic understanding. Mitochondria can be isolated from intact cells, but the yield and quality of the end product is often poor and prone to subselection during isolation. Plasma membrane permeabilization of cells provides a solution to this challenge, allowing experimental control of the medium surrounding the mitochondria. This unit describes techniques to measure respiration in permeabilized adherent cells using a Seahorse XF Analyzer or permeabilized suspended cells in a Hansatech Oxygraph. Copyright © 2014 John Wiley & Sons, Inc.

Arrays of microscopic organic LEDs for high-resolution optogenetics

PubMed Central

Steude, Anja; Witts, Emily C.; Miles, Gareth B.; Gather, Malte C.

2016-01-01

Optogenetics is a paradigm-changing new method to study and manipulate the behavior of cells with light. Following major advances of the used genetic constructs over the last decade, the light sources required for optogenetic control are now receiving increased attention. We report a novel optogenetic illumination platform based on high-density arrays of microscopic organic light-emitting diodes (OLEDs). Because of the small dimensions of each array element (6 × 9 μm2) and the use of ultrathin device encapsulation, these arrays enable illumination of cells with unprecedented spatiotemporal resolution. We show that adherent eukaryotic cells readily proliferate on these arrays, and we demonstrate specific light-induced control of the ionic current across the membrane of individual live cells expressing different optogenetic constructs. Our work paves the way for the use of OLEDs for cell-specific optogenetic control in cultured neuronal networks and for acute brain slices, or as implants in vivo. PMID:27386540

Two Randomized Controlled Pilot Trials of Social Forces to Improve Statin Adherence among Patients with Diabetes.

PubMed

Reese, Peter P; Kessler, Judd B; Doshi, Jalpa A; Friedman, Joelle; Mussell, Adam S; Carney, Caroline; Zhu, Jingsan; Wang, Wenli; Troxel, Andrea; Young, Peinie; Lawnicki, Victor; Rajpathak, Swapnil; Volpp, Kevin

2016-04-01

Medication nonadherence is an important obstacle to cardiovascular disease management. To improve adherence through real-time feedback based on theories of how social forces influence behavior. Two randomized controlled pilot trials called PROMOTE and SUPPORT. Participants stored statin medication in wireless-enabled pill bottles that transmitted adherence data to researchers. Adults with diabetes and a history of low statin adherence based on pharmacy refills (i.e., Medication Possession Ratio [MPR] <80% in the pre-randomization screening period). In PROMOTE, each participant was randomized to 1) weekly messages in which that participant's statin adherence was compared to that of other participants (comparison), 2) weekly summaries of that participant's statin adherence (summary), or 3) control. In SUPPORT, each participant identified another person (the Medication Adherence Partner [MAP]) to receive reports about that participant's adherence, and was randomized to 1) daily reports to MAP, 2) weekly reports to MAP, 3) reports to MAP only if dose was missed, or 4) control. Adherence measured by pill bottle. Among 45,000 health plan members contacted by mail, <1% joined the trial. Participants had low baseline MPRs (median = 60%, IQR 41-72%) but high pill-bottle adherence (90% in PROMOTE, 92% in SUPPORT) during the trial. In PROMOTE (n = 201) and SUPPORT (n = 200), no intervention demonstrated significantly better adherence vs. In a subgroup of PROMOTE participants with the lowest pre-study MPR, pill-bottle-measured adherence in the comparison arm (89%) was higher than the control (86%) and summary (76%) arms, but differences were non-significant (p = 0.10). Interventions based on social forces did not improve medication adherence vs. control over a 3-month period. Given the low percentage of invited individuals who enrolled, the studies may have attracted participants who required little encouragement to improve adherence other than study participation.

[Study of an adherence rating score system for tuberculosis patients in China].

PubMed

Yuan, Yan-li; Yu, Bao-zhu; Jiang, Shi-wen; Wang, Tao; Lv, Jun; Tao, Qiu-Shan

2010-06-18

To develop an adherence rating score (ARS) system specific for tuberculosis (TB) patients. A cross-sectional survey of 124 TB patients was conducted to figure out risk factors for adherence to treatment. The step-wise logistic regression models were used for selecting adherence-related variables. ARS was developed based on the weighting scores of the parameters of all the predicted variables in the logistic model. The reliability and responsibility of ARS was evaluated by using external data from an open label randomized controlled trial on 574 TB patients. The patients were grouped as adherence group (247 patients) and non-adherence group (327 patients) based on the predicted ARS. And the non-adherence group was randomized divided into a trail group (146 patients) and a control group (181 patients). The intervention for the trail group was custom health educational material aimed to reduce ARS, while the intervention for control groups was general TB education material, which was routinely used in the current local TB control settings. The cumulative non-adherence rates of the three groups were compared with each other after six-month follow-up period of treatment. The ARS system had 7 items which covered the following domains: disease status, psychology, patients' KAP (knowledge, attitude, and practice), regularly life-style and social supports. The score of ARS was 2.38+/-0.18 (mean+/-SD) for adherence patients, and 4.69 +/-0.20 (mean+/-SD) for non-adherence patients (t=8.52, P<0.01). In the randomized controlled trial, the six months cumulative non-adherence rates ware 24.7% for the trail group and it was 41.4% for the control group(P<0.01); while the six months cumulative non-adherence rates were not statistical significant difference between trail group and adherence group (P>0.05). The ARS system was reliability and validity for evaluating the adherence of TB treatment in the stop TB settings in China.

Adherence to medication, glycaemic control and hospital attendance in young adults with type 2 diabetes.

PubMed

Kunasegaran, Shalini; Beig, Junaid; Khanolkar, Manish; Cundy, Tim

2018-06-01

Type 2 diabetes is becoming common among people in their 20s and 30s. Glycaemic control is suboptimal in this group and is associated with poor medication adherence. We studied medication adherence over a 24-month period in all diabetes clinic registrants (n = 266) between the ages of 18 and 39 years. We reviewed their glycaemic control using mean HbA1c over the study period and examined hospital records to determine the number of hospital attendances during this time. We found that less than half the group (47%) had good adherence (>90%) and 21% of the group had very poor adherence (<50%). Mean adherence was slightly poorer in women compared to men (73% vs 76%, P = 0.04). There was a marked inverse relationship between adherence and glycaemic control. Mean HbA1c is 70 mmol/mol among those with good adherence and mean HbA1c is 97 mmol/mol among those with very poor adherence (P < 0.05). Fifty-seven per cent of the study group had at least one hospital attendance during this time. Eighty-eight hospital attendances were due to a medical cause. Study of trend showed more medical admissions among those with very poor adherence (P = 0.03). Mean HbA1c was higher in those who required medical admissions (87 mmol/mol vs 75 mmol/mol) when compared to those with no hospital attendance. Our study shows that poor adherence is common and significantly related to glycaemic control as well as unplanned hospital attendances for medical conditions. Despite limitations, our study provides valuable information on medication adherence and its impact on glycaemic control and morbidity among young people with type 2 diabetes. © 2018 Royal Australasian College of Physicians.

Control of cell nucleus shapes via micropillar patterns.

PubMed

Pan, Zhen; Yan, Ce; Peng, Rong; Zhao, Yingchun; He, Yao; Ding, Jiandong

2012-02-01

We herein report a material technique to control the shapes of cell nuclei by the design of the microtopography of substrates to which the cells adhere. Poly(D,L-lactide-co-glycolide) (PLGA) micropillars or micropits of a series of height or depth were fabricated, and some surprising self deformation of the nuclei of bone marrow stromal cells (BMSCs) was found in the case of micropillars with a sufficient height. Despite severe nucleus deformation, BMSCs kept the ability of proliferation and differentiation. We further demonstrated that the shapes of cell nuclei could be regulated by the appropriate micropillar patterns. Besides circular and elliptoid shapes, some unusual nucleus shapes of BMSCs have been achieved, such as square, cross, dumbbell, and asymmetric sphere-protrusion. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

Micropatterning of a nanoporous alumina membrane with poly(ethylene glycol) hydrogel to create cellular micropatterns on nanotopographic substrates.

PubMed

Lee, Hyun Jong; Kim, Dae Nyun; Park, Saemi; Lee, Yeol; Koh, Won-Gun

2011-03-01

In this paper, we describe a simple method for fabricating micropatterned nanoporous substrates that are capable of controlling the spatial positioning of mammalian cells. Micropatterned substrates were prepared by fabricating poly(ethylene glycol) (PEG) hydrogel microstructures on alumina membranes with 200 nm nanopores using photolithography. Because hydrogel precursor solution could infiltrate and become crosslinked within the nanopores, the resultant hydrogel micropatterns were firmly anchored on the substrate without the use of adhesion-promoting monolayers, thereby allow tailoring of the surface properties of unpatterned nanoporous areas. For mammalian cell patterning, arrays of microwells of different dimensions were fabricated. These microwells were composed of hydrophilic PEG hydrogel walls surrounding nanoporous bottoms that were modified with cell-adhesive Arg-Gly-Asp (RGD) peptides. Because the PEG hydrogel was non-adhesive towards proteins and cells, cells adhered selectively and remained viable within the RGD-modified nanoporous regions, thereby creating cellular micropatterns. Although the morphology of cell clusters and the number of cells inside one microwell were dependent on the lateral dimension of the microwells, adhered cells that were in direct contact with nanopores were able to penetrate into the nanopores by small extensions (filopodia) for all the different sizes of microwells evaluated. Copyright © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Citrate, not phosphate, can dissolve calcium oxalate monohydrate crystals and detach these crystals from renal tubular cells.

PubMed

Chutipongtanate, Somchai; Chaiyarit, Sakdithep; Thongboonkerd, Visith

2012-08-15

Dissolution therapy of calcium oxalate monohydrate (COM) kidney stone disease has not yet been implemented due to a lack of well characterized COM dissolution agents. The present study therefore aimed to identify potential COM crystal dissolution compounds. COM crystals were treated with deionized water (negative control), 5 mM EDTA (positive control), 5 mM sodium citrate, or 5mM sodium phosphate. COM crystal dissolution activities of these compounds were evaluated by phase-contrast and video-assisted microscopic examinations, semi-quantitative analysis of crystal size, number and total mass, and spectrophotometric oxalate-dissolution assay. In addition, effects of these compounds on detachment of COM crystals, which adhered tightly onto renal tubular cell surface, were also investigated. The results showed that citrate, not phosphate, had a significant dissolution effect on COM crystals as demonstrated by significant reduction of crystal size (approximately 37% decrease), crystal number (approximately 53% decrease) and total crystal mass (approximately 72% decrease) compared to blank and negative controls. Spectrophotometric oxalate-dissolution assay successfully confirmed the COM crystal dissolution property of citrate. Moreover, citrate could detach up to 85% of the adherent COM crystals from renal tubular cell surface. These data indicate that citrate is better than phosphate for dissolution and detachment of COM crystals. Copyright © 2012 Elsevier B.V. All rights reserved.

A New Lebanese Medication Adherence Scale: Validation in Lebanese Hypertensive Adults.

PubMed

Bou Serhal, R; Salameh, P; Wakim, N; Issa, C; Kassem, B; Abou Jaoude, L; Saleh, N

2018-01-01

A new Lebanese scale measuring medication adherence considered socioeconomic and cultural factors not taken into account by the eight-item Morisky Medication Adherence Scale (MMAS-8). Objectives were to validate the new adherence scale and its prediction of hypertension control, compared to MMAS-8, and to assess adherence rates and factors. A cross-sectional study, including 405 patients, was performed in outpatient cardiology clinics of three hospitals in Beirut. Blood pressure was measured, a questionnaire filled, and sodium intake estimated by a urine test. Logistic regression defined predictors of hypertension control and adherence. 54.9% had controlled hypertension. 82.4% were adherent by the new scale, which showed good internal consistency, adequate questions (KMO coefficient = 0.743), and four factors. It predicted hypertension control (OR = 1.217; p value = 0.003), unlike MMAS-8, but the scores were correlated (ICC average measure = 0.651; p value < 0.001). Stress and smoking predicted nonadherence. This study elaborated a validated, practical, and useful tool measuring adherence to medications in Lebanese hypertensive patients.

Heterogeneity of murine adherent interleukin-2-activated killer cells. Differential effect of prostaglandin E2 and forskolin.

PubMed

Vaillier, D; Daculsi, R; Gualde, N

1995-01-01

We have studied the relationship between cytotoxic activity, size and granularity of murine interleukin-2-activated adherent killer cells issued from spleen cells cultured with high levels of IL-2. The effects of prostaglandin E2 (PGE2) and forskolin upon these cells were assessed. All adherent spleen cells obtained after 5 days of culture were large granular lymphocytes but presented a heterogeneity in size and granularity. After fractionation on a discontinuous-density Percoll gradient, four cellular subpopulations were isolated. Fluorescence-activated cell sorting analysis showed that cells of the lightest fraction (F1) were the largest, while the cells found in the heaviest fraction (F4) were much more granular than the cells collected in the two intermediate fractions (F2 and F3). The serine esterases level was higher in F4 than in unfractionated cells and diminished to about 40% in cells of fractions F2 and F3, which expressed a cytotoxic activity against YAC-1 cells higher than that in unfractionated cells or in F1 or F4, which presented the lowest cytotoxic activity. When AK cells were cultured for 48 h in the presence of either PGE2 or forskolin, which induce an intracellular increase of cAMP, we observed that PGE2 (1 microM) inhibited the cytotoxic activity, but surprisingly forskolin (2 microM) exerted a stimulating effect on the induction of cytotoxic activity. After fractionation on a discontinuous Percoll gradient we observed the same cellular distribution among PGE2 or forskolin-treated or -untreated cells, but PGE2 induced an increase of size and granularity. This effect of PGE2 was more potent on the cells collected in F4. However this variation of granularity was not associated with any variation in the serine esterase level. The cytotoxic activity of PGE2- or forskolin-treated cells did not present any significant variation relative to the control for cells collected in F2 and F3; on the other hand, forskolin-treated cells collected in F4 showed a significantly higher cytotoxicity than did the corresponding untreated or PGE2-treated cells.

Adherence of non-O157 Shiga-toxin Escherichia coli to bovine recto-anal junction squamous epithelial cells appears to be mediated by mechanisms distinct from those used by O157

USDA-ARS?s Scientific Manuscript database

This study presents evidence that the pattern of adherence of clinically relevant non-O157 Shiga-toxin producing Escherichia coli (STEC) to bovine recto-anal junction squamous epithelial cells (RSE) is similar to that of O157, although the mechanisms of adherence appear to be distinct. Our results f...

Galaptin Mediates the Effect of Hypergravity on Vascular Smooth Muscle cell (SMC) Adhesion to Laminin Containing Matrices

NASA Technical Reports Server (NTRS)

Enahora, Fatisha T.; Bosah, Francis N.; Harris-Hooker, Sandra; Sanford, Gary L.

1997-01-01

Galaptin, an endogenous beta-galactoside specific lectin, has been reported to bind to laminin and subsequently decrease the binding of SMC. Cellular function depend on cell:matrix interactions. Hypergravity (HGrav) affect a number of cellular functions, yet little is known about its affect on cell adhesion. We examined the possibility that galaptin mediates the effects of hypergravity on SMC adherence. Confluent primate aorta SMC cultures were subjected to Hgrav (centrifuged at 6G) for 24 and 48 hr. Cells were non-enzymatically dispersed, pretreated with antisense (AS-oligo) or control sense (SS-oligo) oligonucleotides to galaptin mRNA (0.01 micro g/ml), then seeded in uncoated or ECL-matrix coated plates. Adhesion of cells were monitored after 6 hr. HGrav increased adhesion by 100-300% compared to controls. AS-oligo decreased adhesion for both HGrav and control cells. SS-oligo did not affect adhesion for either HGrav or control cells. These studies show that HGrav affects cell adhesion and that galaptin expression is required for this effect.

Is patient empowerment the key to promote adherence? A systematic review of the relationship between self-efficacy, health locus of control and medication adherence

PubMed Central

2017-01-01

Background Current health policies emphasize the need for an equitable doctor-patient relationship, and this requires a certain level of patient empowerment. However, a systematic review of the empirical evidence on how empowerment affects medication adherence—the extent to which patients follow the physician’s prescription of medication intake—is still missing. The goal of this systematic review is to sum up current state-of-the-art knowledge concerning the relationship between patient empowerment and medication adherence across medical conditions. As our conceptualization defines health locus of control and self-efficacy as being crucial components of empowerment, we explored the relationship between these two constructs and medication adherence. Methods Relevant studies were retrieved through a comprehensive search of Medline and PsychINFO databases (1967 to 2017). In total, 4903 publications were identified. After applying inclusion and exclusion criteria and quality assessment, 154 articles were deemed relevant. Peer-reviewed articles, written in English, addressing the relationship between empowerment (predictor) and medication adherence (outcome) were included. Findings High levels of self-efficacy and Internal Health Locus of Control are consistently found to promote medication adherence. External control dimensions were found to have mainly negative (Chance and God attributed control beliefs) or ambiguous (Powerful others attributed control beliefs) links to adherence, except for Doctor Health Locus of Control which had a positive association with medication adherence. To fully capture how health locus of control dimensions influence medication adherence, the interaction between the sub-dimensions and the attitudinal symmetry between the doctor and patient, regarding the patient’s control over the disease management, can provide promising new alternatives. Discussion The beneficial effect of patients’ high internal and concurrent physician-attributed control beliefs suggests that a so-called “joint empowerment” approach can be suitable in order to foster medication adherence, enabling us to address the question of control as a versatile component in the doctor-patient relationship. PMID:29040335

The use of real-time cell analyzer technology in drug discovery: defining optimal cell culture conditions and assay reproducibility with different adherent cellular models.

PubMed

Atienzar, Franck A; Tilmant, Karen; Gerets, Helga H; Toussaint, Gaelle; Speeckaert, Sebastien; Hanon, Etienne; Depelchin, Olympe; Dhalluin, Stephane

2011-07-01

The use of impedance-based label-free technology applied to drug discovery is nowadays receiving more and more attention. Indeed, such a simple and noninvasive assay that interferes minimally with cell morphology and function allows one to perform kinetic measurements and to obtain information on proliferation, migration, cytotoxicity, and receptor-mediated signaling. The objective of the study was to further assess the usefulness of a real-time cell analyzer (RTCA) platform based on impedance in the context of quality control and data reproducibility. The data indicate that this technology is useful to determine the best coating and cellular density conditions for different adherent cellular models including hepatocytes, cardiomyocytes, fibroblasts, and hybrid neuroblastoma/neuronal cells. Based on 31 independent experiments, the reproducibility of cell index data generated from HepG2 cells exposed to DMSO and to Triton X-100 was satisfactory, with a coefficient of variation close to 10%. Cell index data were also well reproduced when cardiomyocytes and fibroblasts were exposed to 21 compounds three times (correlation >0.91, p < 0.0001). The data also show that a cell index decrease is not always associated with cytotoxicity effects and that there are some confounding factors that can affect the analysis. Finally, another drawback is that the correlation analysis between cellular impedance measurements and classical toxicity endpoints has been performed on a limited number of compounds. Overall, despite some limitations, the RTCA technology appears to be a powerful and reliable tool in drug discovery because of the reasonable throughput, rapid and efficient performance, technical optimization, and cell quality control.

Adherence to stainless steel by foodborne microorganisms during growth in model food systems.

PubMed

Hood, S K; Zottola, E A

1997-07-22

Biofilm formation on stainless steel by Salmonella typhimurium, Listeria monocytogenes, Escherichia coli O157:H7, Pseudomonas fragi and Pseudomonas fluorescens during growth in model food systems was studied. Test growth media included tryptic soy broth (TSB), diluted TSB (dTSB), 1% reconstituted skim milk (RSM) and diluted meat juice (DMJ). Adherent cells were stained with acridine orange and enumerated using epifluorescent microscopy and computerized image analysis. Cells were observed on the stainless steel surface after 1 h in all of the media. However, the increases in the number of adherent cells over time was seen only with S. typhimurium in DMJ, E. coli O157:H7 in TSB, dTSB and DMJ, P. fragi in RSM and P. fluorescens in RSM. The medium which produced the highest observed level of adherent cells was different for each microorganism.

Biomaterial adherent macrophage apoptosis is increased by hydrophilic and anionic substrates in vivo

NASA Astrophysics Data System (ADS)

Brodbeck, William G.; Patel, Jasmine; Voskerician, Gabriela; Christenson, Elizabeth; Shive, Matthew S.; Nakayama, Yasuhide; Matsuda, Takehisa; Ziats, Nicholas P.; Anderson, James M.

2002-08-01

An in vivo rat cage implant system was used to identify potential surface chemistries that prevent failure of implanted biomedical devices and prostheses by limiting monocyte adhesion and macrophage fusion into foreign-body giant cells while inducing adherent-macrophage apoptosis. Hydrophobic, hydrophilic, anionic, and cationic surfaces were used for implantation. Analysis of the exudate surrounding the materials revealed no differences between surfaces in the types or levels of cells present. Conversely, the proportion of adherent cells undergoing apoptosis was increased significantly on anionic and hydrophilic surfaces (46 ± 3.7 and 57 ± 5.0%, respectively) when compared with the polyethylene terephthalate base surface. Additionally, hydrophilic and anionic substrates provided decreased rates of monocyte/macrophage adhesion and fusion. These studies demonstrate that biomaterial-adherent cells undergo material-dependent apoptosis in vivo, rendering potentially harmful macrophages nonfunctional while the surrounding environment of the implant remains unaffected.

In Vitro Analysis of Breast Cancer Cell Line Tumourspheres and Primary Human Breast Epithelia Mammospheres Demonstrates Inter- and Intrasphere Heterogeneity

PubMed Central

Vargas, Ana Cristina; Keith, Patricia; Reid, Lynne; Wockner, Leesa; Amiri, Marjan Askarian; Sarkar, Debina; Simpson, Peter T.; Clarke, Catherine; Schmidt, Chris W.; Reynolds, Brent A.

2013-01-01

Mammosphere and breast tumoursphere culture have gained popularity as in vitro assays for propagating and analysing normal and cancer stem cells. Whether the spheres derived from different sources or parent cultures themselves are indeed single entities enriched in stem/progenitor cells compared to other culture formats has not been fully determined. We surveyed sphere-forming capacity across 26 breast cell lines, immunophenotyped spheres from six luminal- and basal-like lines by immunohistochemistry and flow cytometry and compared clonogenicity between sphere, adherent and matrigel culture formats using in vitro functional assays. Analyses revealed morphological and molecular intra- and inter-sphere heterogeneity, consistent with adherent parental cell line phenotypes. Flow cytometry showed sphere culture does not universally enrich for markers previously associated with stem cell phenotypes, although we found some cell-line specific changes between sphere and adherent formats. Sphere-forming efficiency was significantly lower than adherent or matrigel clonogenicity and constant over serial passage. Surprisingly, self-renewal capacity of sphere-derived cells was similar/lower than other culture formats. We observed significant correlation between long-term-proliferating-cell symmetric division rates in sphere and adherent cultures, suggesting functional overlap between the compartments sustaining them. Experiments with normal primary human mammary epithelia, including sorted luminal (MUC1+) and basal/myoepithelial (CD10+) cells revealed distinct luminal-like, basal-like and mesenchymal entities amongst primary mammospheres. Morphological and colony-forming-cell assay data suggested mammosphere culture may enrich for a luminal progenitor phenotype, or induce reversion/relaxation of the basal/mesenchymal in vitro selection occurring with adherent culture. Overall, cell line tumourspheres and primary mammospheres are not homogenous entities enriched for stem cells, suggesting a more cautious approach to interpreting data from these assays and careful consideration of its limitations. Sphere culture may represent an alternative 3-dimensional culture system which rather than universally ‘enriching’ for stem cells, has utility as one of a suite of functional assays that provide a read-out of progenitor activity. PMID:23750209

Acculturation, Medication Adherence, Lifestyle Behaviors, and Blood Pressure Control Among Arab Americans.

PubMed

Tailakh, Ayman K; Evangelista, Lorraine S; Morisky, Donald E; Mentes, Janet C; Pike, Nancy A; Phillips, Linda R

2016-01-01

The aim of this study was to examine the relationship between acculturation, medication adherence, lifestyle behaviors (e.g., physical activity, nutrition, weight control), and blood pressure control among hypertensive Arab Americans. The study utilized a cross-sectional descriptive design. A convenience sample of 126 participants completed questionnaires and had measures of blood pressure, weight, and height. Forty-six participants were hypertensive and were included in the analysis. Only 29.2% of participants reported high medication adherence. High medication adherence was associated with lower diastolic blood pressure, eating a healthy diet, and following lifestyle modifications. Acculturation was significantly associated with physical activity and body mass index. Our study found that acculturated participants were more adherent to medications and physical activity and had better blood pressure control. Further studies are needed to explore how acculturation improves adherence and what factors contribute to better adherence in order to design culturally sensitive interventions. © The Author(s) 2014.

Acculturation, Medication Adherence, Lifestyle Behaviors, and Blood Pressure Control Among Arab Americans

PubMed Central

Tailakh, Ayman K.; Evangelista, Lorraine S.; Morisky, Donald E.; Mentes, Janet C.; Pike, Nancy A.; Phillips, Linda R.

2015-01-01

Purpose The aim of this study was to examine the relationship between acculturation, medication adherence, lifestyle behaviors (e.g., physical activity, nutrition, weight control), and blood pressure control among hypertensive Arab Americans. Design The study utilized a cross-sectional descriptive design. A convenience sample of 126 participants completed questionnaires and had measures of blood pressure, weight, and height. Forty-six participants were hypertensive and were included in the analysis. Results Only 29.2% of participants reported high medication adherence. High medication adherence was associated with lower diastolic blood pressure, eating a healthy diet, and following lifestyle modifications. Acculturation was significantly associated with physical activity and body mass index. Conclusion Our study found that acculturated participants were more adherent to medications and physical activity and had better blood pressure control. Further studies are needed to explore how acculturation improves adherence and what factors contribute to better adherence in order to design culturally sensitive interventions. PMID:24848347

Stem cell behavior on tailored porous oxide surface coatings.

PubMed

Lavenus, Sandrine; Poxson, David J; Ogievetsky, Nika; Dordick, Jonathan S; Siegel, Richard W

2015-07-01

Nanoscale surface topographies are known to have a profound influence on cell behavior, including cell guidance, migration, morphology, proliferation, and differentiation. In this study, we have observed the behavior of human mesenchymal stem cells cultured on a range of tailored porous SiO2 and TiO2 nanostructured surface coatings fabricated via glancing angle electron-beam deposition. By controlling the physical vapor deposition angle during fabrication, we could control systematically the deposited coating porosity, along with associated topographic features. Immunocytochemistry and image analysis quantitatively revealed the number of adherent cells, as well as their basic cellular morphology, on these surfaces. Signaling pathway studies showed that even with subtle changes in nanoscale surface structures, the behavior of mesenchymal stem cells was strongly influenced by the precise surface structures of these porous coatings. Copyright © 2015 Elsevier Ltd. All rights reserved.

Suppression of unprimed T and B cells in antibody responses by irradiation-resistant and plastic-adherent suppressor cells in Toxoplasma gondii-infected mice

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

Suzuki, Y.; Kobayashi, A.

1983-04-01

In the acute phase of Toxoplasma infection, the function of both helper T and B cells was suppressed in primary antibody responses to dinitrophenol (DNP)-conjugated protein antigens. During the course of infection, the suppressive effect on T cells seems to continue longer than that on B cells, since suppression in responses to sheep erythrocytes, a T-dependent antigen, persisted longer than those to DNP-Ficoll, a T-independent antigen. Plastic-adherent cells from the spleens of Toxoplasma-infected and X-irradiated (400 rads) mice had strong suppressor activity in primary anti-sheep erythrocyte antibody responses of normal mouse spleen cells in vitro. These data suggest that themore » activation of irradiation-resistant and plastic-adherent suppressor cells causes the suppression of both T and B cells in Toxoplasma-infected mice.« less

Influence of neighboring adherent cells on laminar flow induced shear stress in vitro—A systematic study

PubMed Central

Djukelic, Mario; Westerhausen, Christoph

2017-01-01

Cells experience forces if subjected to laminar flow. These forces, mostly of shear force character, are strongly dependent not only on the applied flow field itself but also on hydrodynamic effects originating from neighboring cells. This particularly becomes important for the interpretation of data from in vitro experiments in flow chambers without confluent cell layers. By employing numerical Finite Element Method simulations of such assemblies of deformable objects under shear flow, we investigate the occurring stress within elastic adherent cells and the influence of neighboring cells on these quantities. For this, we simulate single and multiple adherent cells of different shapes fixed on a solid substrate under laminar flow parallel to the substrate for different velocities. We determine the local stress within the cells close to the cell-substrate-interface and the overall stress of the cells by surface integration over the cell surface. Comparing each measurand in the case of a multiple cell situation with the corresponding one of single cells under identical conditions, we introduce a dimensionless influence factor. The systematic variation of the distance and angle between cells, where the latter is with respect to the flow direction, flow velocity, Young's modulus, cell shape, and cell number, enables us to describe the actual influence on a cell. Overall, we here demonstrate that the cell density is a crucial parameter for all studies on flow induced experiments on adherent cells in vitro. PMID:28798851

Dynamic Adhesion of Umbilical Cord Blood Endothelial Progenitor Cells under Laminar Shear Stress

PubMed Central

Angelos, Mathew G.; Brown, Melissa A.; Satterwhite, Lisa L.; Levering, Vrad W.; Shaked, Natan T.; Truskey, George A.

2010-01-01

Late outgrowth endothelial progenitor cells (EPCs) represent a promising cell source for rapid reendothelialization of damaged vasculature after expansion ex vivo and injection into the bloodstream. We characterized the dynamic adhesion of umbilical-cord-blood-derived EPCs (CB-EPCs) to surfaces coated with fibronectin. CB-EPC solution density affected the number of adherent cells and larger cells preferentially adhered at lower cell densities. The number of adherent cells varied with shear stress, with the maximum number of adherent cells and the shear stress at maximum adhesion depending upon fluid viscosity. CB-EPCs underwent limited rolling, transiently tethering for short distances before firm arrest. Immediately before arrest, the instantaneous velocity decreased independent of shear stress. A dimensional analysis indicated that adhesion was a function of the net force on the cells, the ratio of cell diffusion to sliding speed, and molecular diffusivity. Adhesion was not limited by the settling rate and was highly specific to α5β1 integrin. Total internal reflection fluorescence microscopy showed that CB-EPCs produced multiple contacts of α5β1 with the surface and the contact area grew during the first 20 min of attachment. These results demonstrate that CB-EPC adhesion from blood can occur under physiological levels of shear stress. PMID:21112278

A qualitative study investigating the use of a mobile phone short message service designed to improve HIV adherence and retention in care in Canada (WelTel BC1).

PubMed

Smillie, Kirsten; Van Borek, Natasha; Abaki, Joshua; Pick, Neora; Maan, Evelyn J; Friesen, Karen; Graham, Rebecca; Levine, Sarah; van der Kop, Mia L; Lester, Richard T; Murray, Melanie

2014-01-01

Patient engagement in care and adherence to medication are critical to achieving the full benefits of antiretroviral therapy (ART) among people with HIV infection. A randomized controlled trial in Kenya, WelTelKenya1, showed that an interactive mobile phone text-messaging intervention can improve adherence and viral load suppression. We conducted a pilot study to adapt the WelTel intervention for HIV-infected clients (n = 25) at an HIV clinic in Vancouver, British Columbia. Between April and June 2012, we recruited five participants from five groups: youth (14-24 years), mature (≥50 years), English as a second language, remote (≥3 hours travel time to clinic), and nonsuppressed (CD4+ T cell count <200 cells/mm(3) and viral load ≥250 copies/mL on two consecutive occasions). Participants described the intervention as a useful way to communicate with health care providers, thus increasing the ability to access services, report side effects, and attend appointments. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Identification of Burkholderia mallei and Burkholderia pseudomallei adhesins for human respiratory epithelial cells.

PubMed

Balder, Rachel; Lipski, Serena; Lazarus, John J; Grose, William; Wooten, Ronald M; Hogan, Robert J; Woods, Donald E; Lafontaine, Eric R

2010-09-28

Burkholderia pseudomallei and Burkholderia mallei cause the diseases melioidosis and glanders, respectively. A well-studied aspect of pathogenesis by these closely-related bacteria is their ability to invade and multiply within eukaryotic cells. In contrast, the means by which B. pseudomallei and B. mallei adhere to cells are poorly defined. The purpose of this study was to identify adherence factors expressed by these organisms. Comparative sequence analyses identified a gene product in the published genome of B. mallei strain ATCC23344 (locus # BMAA0649) that resembles the well-characterized Yersinia enterocolitica autotransporter adhesin YadA. The gene encoding this B. mallei protein, designated boaA, was expressed in Escherichia coli and shown to significantly increase adherence to human epithelial cell lines, specifically HEp2 (laryngeal cells) and A549 (type II pneumocytes), as well as to cultures of normal human bronchial epithelium (NHBE). Consistent with these findings, disruption of the boaA gene in B. mallei ATCC23344 reduced adherence to all three cell types by ~50%. The genomes of the B. pseudomallei strains K96243 and DD503 were also found to contain boaA and inactivation of the gene in DD503 considerably decreased binding to monolayers of HEp2 and A549 cells and to NHBE cultures.A second YadA-like gene product highly similar to BoaA (65% identity) was identified in the published genomic sequence of B. pseudomallei strain K96243 (locus # BPSL1705). The gene specifying this protein, termed boaB, appears to be B. pseudomallei-specific. Quantitative attachment assays demonstrated that recombinant E. coli expressing BoaB displayed greater binding to A549 pneumocytes, HEp2 cells and NHBE cultures. Moreover, a boaB mutant of B. pseudomallei DD503 showed decreased adherence to these respiratory cells. Additionally, a B. pseudomallei strain lacking expression of both boaA and boaB was impaired in its ability to thrive inside J774A.1 murine macrophages, suggesting a possible role for these proteins in survival within professional phagocytic cells. The boaA and boaB genes specify adhesins that mediate adherence to epithelial cells of the human respiratory tract. The boaA gene product is shared by B. pseudomallei and B. mallei whereas BoaB appears to be a B. pseudomallei-specific adherence factor.

Functionalized iron oxide nanoparticles for controlling the movement of immune cells

NASA Astrophysics Data System (ADS)

White, Ethan E.; Pai, Alex; Weng, Yiming; Suresh, Anil K.; van Haute, Desiree; Pailevanian, Torkom; Alizadeh, Darya; Hajimiri, Ali; Badie, Behnam; Berlin, Jacob M.

2015-04-01

Immunotherapy is currently being investigated for the treatment of many diseases, including cancer. The ability to control the location of immune cells during or following activation would represent a powerful new technique for this field. Targeted magnetic delivery is emerging as a technique for controlling cell movement and localization. Here we show that this technique can be extended to microglia, the primary phagocytic immune cells in the central nervous system. The magnetized microglia were generated by loading the cells with iron oxide nanoparticles functionalized with CpG oligonucleotides, serving as a proof of principle that nanoparticles can be used to both deliver an immunostimulatory cargo to cells and to control the movement of the cells. The nanoparticle-oligonucleotide conjugates are efficiently internalized, non-toxic, and immunostimulatory. We demonstrate that the in vitro migration of the adherent, loaded microglia can be controlled by an external magnetic field and that magnetically-induced migration is non-cytotoxic. In order to capture video of this magnetically-induced migration of loaded cells, a novel 3D-printed ``cell box'' was designed to facilitate our imaging application. Analysis of cell movement velocities clearly demonstrate increased cell velocities toward the magnet. These studies represent the initial step towards our final goal of using nanoparticles to both activate immune cells and to control their trafficking within the diseased brain.Immunotherapy is currently being investigated for the treatment of many diseases, including cancer. The ability to control the location of immune cells during or following activation would represent a powerful new technique for this field. Targeted magnetic delivery is emerging as a technique for controlling cell movement and localization. Here we show that this technique can be extended to microglia, the primary phagocytic immune cells in the central nervous system. The magnetized microglia were generated by loading the cells with iron oxide nanoparticles functionalized with CpG oligonucleotides, serving as a proof of principle that nanoparticles can be used to both deliver an immunostimulatory cargo to cells and to control the movement of the cells. The nanoparticle-oligonucleotide conjugates are efficiently internalized, non-toxic, and immunostimulatory. We demonstrate that the in vitro migration of the adherent, loaded microglia can be controlled by an external magnetic field and that magnetically-induced migration is non-cytotoxic. In order to capture video of this magnetically-induced migration of loaded cells, a novel 3D-printed ``cell box'' was designed to facilitate our imaging application. Analysis of cell movement velocities clearly demonstrate increased cell velocities toward the magnet. These studies represent the initial step towards our final goal of using nanoparticles to both activate immune cells and to control their trafficking within the diseased brain. Electronic supplementary information (ESI) available: Transmission electron microscopy images of the particles, additional independent experiments for the NFκB activity and exocytosis assays, TEM images for the SPION untreated cells, bright field microscopy images of the cells alone in the presence and absence of magnet, images of the magnetic movement experiments at higher doses of SPION, full uncropped images of the post-migration LIVE/DEAD assay, and a video file of cell movement. See DOI: 10.1039/c3nr04421a

Knowledge, adherence and control among patients with hypertension attending a peri-urban primary health care clinic, KwaZulu-Natal

PubMed Central

2017-01-01

Background Despite hypertension being a common condition among patients attending primary health care (PHC) clinics, blood pressure (BP) control is often poor. Greater insight into patient-related factors that influence the control of hypertension will assist in the development of an intervention to address the issues identified. Aim The aim of the study was to assess patient-related variables associated with hypertension control among patients attending a peri-urban PHC clinic. Setting The setting for this study was a peri-urban PHC clinic in KwaZulu-Natal. Method This was an observational, descriptive and cross-sectional study with 348 patients selected over a 1-month period. A validated questionnaire was used to collect data on patients’ hypertension knowledge and self-reported adherence, and BP recordings from their medical record were recorded to ascertain control. Results Of the 348 participants, only 49% had good BP control and 44% (152/348) had concurrent diabetes mellitus. The majority of patients had moderate levels of knowledge on hypertension and exhibited moderate adherence. There was a significant relationship between knowledge and reported adherence, between reported adherence and control, but not between reported knowledge and control. Conclusion Despite over 90% of the study population having moderate knowledge, and 62% with moderate reported adherence, BP was well controlled in only less than 50% of the study population. These findings suggest a need to emphasise adherence and explore new ways of approaching adherence. PMID:29113443

Behavioral and Pharmacological Adherence in Pediatric Sickle Cell Disease: Parent-Child Agreement and Family Factors Associated With Adherence.

PubMed

Klitzman, Page H; Carmody, Julia K; Belkin, Mary H; Janicke, David M

2018-01-01

This study aimed to evaluate agreement between children and parents on a measure of behavioral and pharmacological adherence in children with sickle cell disease (SCD), and the associations among family factors (i.e., problem-solving skills, routines, communication) and adherence behaviors. In all, 85 children (aged 8-18 years) with SCD and their parents completed questionnaires assessing individual and family factors. Overall parent-child agreement on an adherence measure was poor, particularly for boys and older children. Greater use of child routines was associated with better overall child-reported adherence. Open family communication was associated with higher overall parent-reported adherence. While further research is needed before definitive conclusions can be drawn, results suggest the need to assess child adherence behaviors via both child and parent reports. Findings also suggest that more daily family routines and open family communication may be protective factors for better disease management. © The Author 2017. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Quantification of endocytosis using a folate functionalized silica hollow nanoshell platform

PubMed Central

Sandoval, Sergio; Mendez, Natalie; Alfaro, Jesus G.; Yang, Jian; Aschemeyer, Sharraya; Liberman, Alex; Trogler, William C.; Kummel, Andrew C.

2015-01-01

Abstract. A quantification method to measure endocytosis was designed to assess cellular uptake and specificity of a targeting nanoparticle platform. A simple N-hydroxysuccinimide ester conjugation technique to functionalize 100-nm hollow silica nanoshell particles with fluorescent reporter fluorescein isothiocyanate and folate or polyethylene glycol (PEG) was developed. Functionalized nanoshells were characterized using scanning electron microscopy and transmission electron microscopy and the maximum amount of folate functionalized on nanoshell surfaces was quantified with UV-Vis spectroscopy. The extent of endocytosis by HeLa cervical cancer cells and human foreskin fibroblast (HFF-1) cells was investigated in vitro using fluorescence and confocal microscopy. A simple fluorescence ratio analysis was developed to quantify endocytosis versus surface adhesion. Nanoshells functionalized with folate showed enhanced endocytosis by cancer cells when compared to PEG functionalized nanoshells. Fluorescence ratio analyses showed that 95% of folate functionalized silica nanoshells which adhered to cancer cells were endocytosed, while only 27% of PEG functionalized nanoshells adhered to the cell surface and underwent endocytosis when functionalized with 200 and 900  μg, respectively. Additionally, the endocytosis of folate functionalized nanoshells proved to be cancer cell selective while sparing normal cells. The developed fluorescence ratio analysis is a simple and rapid verification/validation method to quantify cellular uptake between datasets by using an internal control for normalization. PMID:26315280

Lulo cell line derived from Lutzomyia longipalpis (Diptera: Psychodidae): a novel model to assay Leishmania spp. and vector interaction

PubMed Central

2011-01-01

Background Leishmania (Vianna) braziliensis, Leishmania (Leishmania) amazonensis and Leishmania (Leishmania) chagasi are important parasites in the scenario of leishmaniasis in Brazil. During the life cycle of these parasites, the promastigote forms adhere to the midgut epithelial microvillii of phlebotomine insects to avoid being secreted along with digestive products. Lulo cells are a potential model that will help to understand the features of this adhesion phenomenon. Here, we analyze the interaction between Leishmania spp. promastigotes and Lulo cells in vitro, specifically focusing on adhesion events occurring between three Leishmania species and this cell line. Methods Confluent monolayers of Lulo cells were incubated with promastigotes and adhesion was assessed using both light microscopy and scanning electron microscopy. Findings The results indicate that species from the subgenera Leishmania and Viannia have great potential to adhere to Lulo cells. The highest adherence rate was observed for L. (L.) chagasi after 24 h of incubation with Lulo cells (27.3 ± 1.8% of cells with adhered promastigotes), followed by L. (L.) amazonensis (16.0 ± 0.7%) and L. (V.) braziliensis (3.0 ± 0.7%), both after 48 h. In the ultrastructural analysis, promastigote adherence was also assessed by scanning electron microscopy, showing that, for parasites from both subgenera, adhesion occurs by both the body and the flagellum. The interaction of Lulo cells with Leishmania (L.) chagasi showed the participation of cytoplasmic projections from the former closely associating the parasites with the cells. Conclusions We present evidence that Lulo cells can be useful in studies of insect-parasite interactions for Leishmania species. PMID:22082050

[Isolation and purification of BMScs of GFP transgenic mouse using the method of adhering to cuture plastic in different time].

PubMed

Li, Fu-Qiang; Zhou, Hong-Ying; Yang, Hui-Lun; Xiang, Tao; Mei, Yan; Hu, Huo-Zhen; Wang, Ting-Hua

2006-03-01

To adopt the method of adhering to culture plastic in different time for cultivating and purifying BMSCs of green fluorescent protein (GFP) transgenic mice. Bone marrow cells isolated from GFP transgenic mice are directly planted in culture flask and an exchange of the total volume medium is made at different time. Then the cells adhering to culture plastic are differently counted according to the cell types and are examined by immunohistochemistry using the antibodies of CD44, CD45 and CD54 in three days. Moreover, the cells after the exchange of the total volume medium in 4 hours, 8 hours and 24 hours are selected and successively subcultured down to the fifth passage. Then the result of amplification is calculated and the cells are examined by immunohistochemistry using the antibodies of CD44, CD45 and CD54. With the extending of the time for the first exchange of medium, the density of cells adhering to culture plastic increased accordingly, but the BMSCs proportion decreased. The cells after first exchange of medium in 4 hours had high BMSCs proportion but low BMSCs density, and the cells in 24 hours had high BMSCs density and low BMSCs proportion. However, the cells in 8-10 hours had high BMSCs density and also high BMSCs proportion. The subcultured BMSCs could stably express GFP. The method of adhering to culture plastic in different time for cultivating and purifying BMSCs of GFP transgenic mice is effective. It is suitable to make the first exchange of total volume medium in 8-10 hours. The subcultured cell has the capacity for amplification and will probably be a seed cell for the research of tissue engineering and gene therapy.

Enrichment isolation of adipose-derived stem/stromal cells from the liquid portion of liposuction aspirates with the use of an adherent column.

PubMed

Doi, Kentaro; Kuno, Shinichiro; Kobayashi, Akira; Hamabuchi, Takahisa; Kato, Harunosuke; Kinoshita, Kahori; Eto, Hitomi; Aoi, Noriyuki; Yoshimura, Kotaro

2014-03-01

Adipose-derived stem/progenitor cells (ASCs) are typically obtained from the lipoaspirates; however, a smaller number of ASCs can be isolated without enzymatic digestion from the infranatant liposuction aspirate fluid (LAF). We evaluated the effectiveness of an adherent column, currently used to isolate mesenchymal stromal cells from bone marrow, to isolate LAF cells. We applied peripheral blood (PB), PB mixed with cultured ASCs (PB-ASC), and LAF solution to the column and divided it into two fractions, the adherent (positive) and the non-adherent (negative) fractions. We compared this method with hypotonic hemolysis (lysis) for the red blood cell count, nucleated cells count and cell compositions as well as functional properties of isolated mesenchymal cells. The column effectively removed red blood cells, though the removal efficiency was slightly inferior to hemolysis. After column processing of PB-ASC, 60.5% of ASCs (53.2% by lysis) were selectively collected in the positive fraction, and the negative fraction contained almost no ASCs. After processing of LAF solution, nucleated cell yields were comparable between the column and hemolysis; however, subsequent adherent culture indicated that a higher average ASC yield was obtained from the column-positive samples than from the lysis samples, suggesting that the column method may be superior to hemolysis for obtaining viable ASCs. Mesenchymal differentiation and network formation assays showed no statistical differences in ASC functions between the lysis and column-positive samples. Our results suggest that a column with non-woven rayon and polyethylene fabrics is useful for isolating stromal vascular fraction cells from LAF solutions for clinical applications. Copyright © 2014 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Monocyte activation by smooth muscle cell-derived matrices.

PubMed

Kaufmann, J; Jorgensen, R W; Martin, B M; Franzblau, C

1990-12-01

Mononuclear phagocytes adhere to and penetrate the vessel wall endothelium and contact the subendothelial space prior to the development of the atherosclerotic plaque. In an attempt to model the early events of plaque development we used an elastin-rich, multicomponent, cell-derived matrix from neonatal rat aortic smooth muscle cells as a substratum for monocytes. Using this model, we show that human monocyte morphology and metabolism are markedly altered by the matrix substratum. When a mixed mononuclear cell population is seeded on matrix or plastic, only monocytes adhere to the matrix surface. In contrast, lymphocytes as well as monocytes adhere to the plastic surface. The matrix-adherent monocytes develop large intracellular granules and form extensive clusters of individual cells. Metabolically, these cells develop sodium fluoride resistant non-specific esterase activity and their media contain more growth factor activity and PGE2. Although total protein synthesis is equivalent in both cultures, the matrix contact induces an increase in specific proteins in the media. We also show that a purified alpha-elastin substratum induces some, but not all, of the monocyte changes seen when using the matrix substratum. Using the alpha-elastin substratum, there is selective adhesion of monocytes and increased growth factor activity, however, the cells are morphologically different from the matrix-adherent cells. Thus, the use of the smooth muscle cell-derived matrix, in conjunction with purified matrix components, serves as a model that can provide insight into the mechanisms of monocyte adhesion and stimulation by the matrix environment that exists in vivo. Such mechanisms may be particularly important in atherogenesis.

Barriers to medication adherence in poorly controlled diabetes mellitus.

PubMed

Odegard, Peggy Soule; Gray, Shelly L

2008-01-01

The purpose of this study is to characterize the adherence and medication management barriers for adults with poorly controlled type 2 diabetes mellitus (DM) (those with A1c 9% or above) and to identify specific adherence characteristics associated with poor diabetes control. This was a cross-sectional analysis of baseline data from a randomized, controlled diabetes intervention conducted in University of Washington (UW) Medicine Clinics in the greater Seattle, Washington, area. The goal of the original study was to evaluate the effect of a pharmacist intervention on improving diabetes control over 12 months. Evaluation measures for medication adherence included self-reported adherence and medication management challenges using the Morisky question format and difficulty with taking medications for each diabetes medication based on the Brief Medication Questionnaire. Specific adherence characteristics associated with poor diabetes control (A1c >9%) were identified using multivariate regression analysis. Seventy-seven subjects (mean A1c, 10.4%; mean duration of DM, 7 years) were studied. The most common adherence challenges included paying for medications (34%), remembering doses (31%), reading prescription labels (21%), and obtaining refills (21%). Taking more than 2 doses of DM medication daily (beta = .78, SE = 0.32, P = .02) and difficulty reading the DM medication prescription label (beta = .76, SE = 0.37, P = .04) were significantly associated with higher hemoglobin A1c. Self-reported adherence was not related to A1c control. In this study, we identified 2 factors that were associated with poorer A1c control. These findings highlight the importance of identifying potential challenges to medication adherence for those with DM and providing support to minimize or resolve these barriers to control.

Microbial colonization of irradiated pathogenic yeast to catheter surfaces: Relationship between adherence, cell surface hydrophobicity, biofilm formation and antifungal susceptibility. A scanning electron microscope analysis.

PubMed

Farrag, Hala Abdallah; A-Karam El-Din, Alzahraa; Mohamed El-Sayed, Zeinab Galal; Abdel-Latifissa, Soheir; Kamal, Mona Mohamed

2015-06-01

Technological advances such as long-term indwelling catheters have created milieu in which infections are a major complication. Thus it is essential to be able to recognize, diagnose, and treat infections occurring in immunocompromised patients. Adherence assay and quantitation of biofilms was performed by a spectrophotometric method, hydrophobicity was evaluated by adhesion to p-xylene. The minimum inhibitory concentration (MIC) of Nystatin was carried out by a well dilution method. Out of 100 bladder cancer patients, 23 pathogenic yeast isolates were identified. The samples were taken from urinary catheters and urine collected from their attached drainage bags. Pathogenic yeast identified were species of Candida, Cryptococcus, Saccharomyces, Blastoschizomyces, Trichosporn, Hansenula, Prototheca and Rhodotorula. With the exception of Rhodotorula minuta, the yeast were sensitive to the antimycotic agent (Nystatin) used before and after in vitro gamma irradiation at 24.41 Gy as measured by a disc diffusion method. All tested yeast strains were slime producers and showed positive adherence reactions. There were considerable differences in adherence measurements after irradiation. An increase in adherence measurement values (using a spectrophotometric method) after irradiation were detected in four strains whereas eight other strains showed a reduction in their adherence reaction. The cell surface hydrophobicity (CSH) was evaluated by adhesion to p-xylene. Candida tropicalis showed a hydrophobic reaction with an increase in the cell surface hydrophobicity after irradiation. Scanning electron microscopy of irradiated C. tropicalis showed marked abnormalities in cell shape and size with significant reduction in adherence ability at the MIC level of Nystatin (4 μg/ml). More basic research at the level of pathogenesis and catheter substance is needed to design novel strategies to prevent fungal adherence and to inhibit biofilm formation.

High throughput single cell counting in droplet-based microfluidics.

PubMed

Lu, Heng; Caen, Ouriel; Vrignon, Jeremy; Zonta, Eleonora; El Harrak, Zakaria; Nizard, Philippe; Baret, Jean-Christophe; Taly, Valérie

2017-05-02

Droplet-based microfluidics is extensively and increasingly used for high-throughput single-cell studies. However, the accuracy of the cell counting method directly impacts the robustness of such studies. We describe here a simple and precise method to accurately count a large number of adherent and non-adherent human cells as well as bacteria. Our microfluidic hemocytometer provides statistically relevant data on large populations of cells at a high-throughput, used to characterize cell encapsulation and cell viability during incubation in droplets.

Factors influencing adherence to psychopharmacological medications in psychiatric patients: a structural equation modeling approach.

PubMed

De Las Cuevas, Carlos; de Leon, Jose; Peñate, Wenceslao; Betancort, Moisés

2017-01-01

To evaluate pathways through which sociodemographic, clinical, attitudinal, and perceived health control variables impact psychiatric patients' adherence to psychopharmacological medications. A sample of 966 consecutive psychiatric outpatients was studied. The variables were sociodemographic (age, gender, and education), clinical (diagnoses, drug treatment, and treatment duration), attitudinal (attitudes toward psychopharmacological medication and preferences regarding participation in decision-making), perception of control over health (health locus of control, self-efficacy, and psychological reactance), and level of adherence to psychopharmacological medications. Structural equation modeling was applied to examine the nonstraightforward relationships and the interactive effects among the analyzed variables. Structural equation modeling demonstrated that psychiatric patients' treatment adherence was associated: 1) negatively with cognitive psychological reactance (adherence decreased as cognitive psychological reactance increased), 2) positively with patients' trust in their psychiatrists (doctors' subscale), 3) negatively with patients' belief that they are in control of their mental health and that their mental health depends on their own actions (internal subscale), and 4) positively (although weakly) with age. Self-efficacy indirectly influenced treatment adherence through internal health locus of control. This study provides support for the hypothesis that perceived health control variables play a relevant role in psychiatric patients' adherence to psychopharmacological medications. The findings highlight the importance of considering prospective studies of patients' psychological reactance and health locus of control as they may be clinically relevant factors contributing to adherence to psychopharmacological medications.

The role of Mycobacterium avium complex fibronectin attachment protein in adherence to the human respiratory mucosa.

PubMed

Middleton, A M; Chadwick, M V; Nicholson, A G; Dewar, A; Groger, R K; Brown, E J; Wilson, R

2000-10-01

Mycobacterium avium complex (MAC) are opportunistic respiratory pathogens that infect non-immunocompromised patients with established lung disease, although they can also cause primary infections. The ability to bind fibronectin is conserved among many mycobacterial species. We have investigated the adherence of a sputum isolate of MAC to the mucosa of organ cultures constructed with human tissue and the contribution of M. avium fibronectin attachment protein (FAP) to the process. MAC adhered to fibrous, but not globular mucus, and to extracellular matrix (ECM) in areas of epithelial damage, but not to intact extruded cells and collagen fibres. Bacteria occasionally adhered to healthy unciliated epithelium and to cells that had degenerated exposing their contents, but never to ciliated cells. The results obtained with different respiratory tissues were similar. Two ATCC strains of MAC gave similar results. There was a significant reduction (P < 0.05) in the number of bacteria adhering to ECM after preincubation of bacteria with fibronectin and after preincubation of the tissue with M. avium FAP in a concentration-dependant manner. The number of bacteria adhering to fibrous mucus was unchanged. Immunogold labelling demonstrated fibronectin in ECM as well as in other areas of epithelial damage, but only ECM bound FAP. A Mycobacterium smegmatis strain had the same pattern of adherence to the mucosa as MAC. When the FAP gene was deleted, the strain demonstrated reduced adherence to ECM, and adherence was restored when the strain was transfected with an M. avium FAP expression construct. We conclude that MAC adheres to ECM in areas of epithelial damage via FAP and to mucus with a fibrous appearance via another adhesin. Epithelial damage exposing ECM and poor mucus clearance will predispose to MAC airway infection.

A functional collagen adhesin gene, acm, in clinical isolates of Enterococcus faecium correlates with the recent success of this emerging nosocomial pathogen.

PubMed

Nallapareddy, Sreedhar R; Singh, Kavindra V; Okhuysen, Pablo C; Murray, Barbara E

2008-09-01

Enterococcus faecium recently evolved from a generally avirulent commensal into a multidrug-resistant health care-associated pathogen causing difficult-to-treat infections, but little is known about the factors responsible for this change. We previously showed that some E. faecium strains express a cell wall-anchored collagen adhesin, Acm. Here we analyzed 90 E. faecium isolates (99% acm(+)) and found that the Acm protein was detected predominantly in clinically derived isolates, while the acm gene was present as a transposon-interrupted pseudogene in 12 of 47 isolates of nonclinical origin. A highly significant association between clinical (versus fecal or food) origin and collagen adherence (P

The activation of human endogenous retrovirus K (HERV-K) is implicated in melanoma cell malignant transformation

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

Serafino, A.; Balestrieri, E.; Pierimarchi, P.

2009-03-10

Melanoma development is a multi-step process arising from a series of genetic and epigenetic events. Although the sequential stages involved in progression from melanocytes to malignant melanoma are clearly defined, our current understanding of the mechanisms leading to melanoma onset is still incomplete. Growing evidence show that the activation of endogenous retroviral sequences might be involved in transformation of melanocytes as well as in the increased ability of melanoma cells to escape immune surveillance. Here we show that human melanoma cells in vitro undergo a transition from adherent to a more malignant, non-adherent phenotype when exposed to stress conditions. Melanoma-derivedmore » non-adherent cells are characterized by an increased proliferative potential and a decreased expression of both HLA class I molecules and Melan-A/MART-1 antigen, similarly to highly malignant cells. These phenotypic and functional modifications are accompanied by the activation of human endogenous retrovirus K expression (HERV-K) and massive production of viral-like particles. Down-regulation of HERV-K expression by RNA interference prevents the transition from the adherent to the non-adherent growth phenotype in low serum. These results implicate HERV-K in at least some critical steps of melanoma progression.« less

Haemophilus parasuis serovar 5 Nagasaki strain adheres and invades PK-15 cells.

PubMed

Frandoloso, Rafael; Martínez-Martínez, Sonia; Gutiérrez-Martín, César B; Rodríguez-Ferri, Elías F

2012-01-27

Haemophilus parasuis is the agent responsible for causing Glässer's disease, which is characterized by fibrinous polyserositis, polyarthritis and meningitis in pigs. The purpose of this study was to investigate the in vitro ability of two H. parasuis serovars of different virulence (serovar 5, Nagasaki strain, highly virulent, belonging to serovar 5, and SW114 strain, nonvirulent, belonging to serovar 3) to adhere to and invade porcine kidney epithelial cells (PK-15 line). Nagasaki strain was able to attach at high levels from 60 to 180 min of incubation irrespective of the concentrations compared (10(7)-10(10)CFU), and a substantial increase of surface projections could be seen in PK-15 cells by scanning electron microscopy. This virulent strain was also able to invade effectively these epithelial cells, and the highest invasion capacity was reached at 180 min of infection. On the contrary, nonvirulent SW114 strain hardly adhered to PK-15 cells, and it did not invade these cells, thus suggesting that adherence and invasion of porcine kidney epithelial cells could be a virulence mechanism involved in the lesions caused by H. parasuis Nagasaki strain in this organ. Copyright © 2011 Elsevier B.V. All rights reserved.

Infection Control Practice in the Operating Room: Staff Adherence to Existing Policies in a Developing Country

PubMed Central

Cawich, Shamir O; Tennant, Ingrid A; McGaw, Clarence D; Harding, Hyacinth; Walters, Christine A; Crandon, Ivor W

2013-01-01

Context: Infection control interventions are important for containing surgery-related infections. For this reason, the modern operating room (OR) should have well-developed infection control policies. The efficacy of these policies depends on how well the OR staff adhere to them. There is a lack of available data documenting adherence to infection control policies. Objective: To evaluate OR staff adherence to existing infection control policies in Jamaica. Methods: We administered a questionnaire to all OR staff to assess their training, knowledge of local infection control protocols, and practice with regard to 8 randomly selected guidelines. Adherence to each guideline was rated with fixed-choice items on a 4-point Likert scale. The sum of points determined the adherence score. Two respondent groups were defined: adherent (score > 26) and nonadherent (score ≤ 26). We evaluated the relationship between respondent group and age, sex, occupational rank, and time since completion of basic medical training. We used χ2 and Fisher exact tests to assess associations and t tests to compare means between variables of interest. Results: The sample comprised 132 participants (90 physicians and 42 nurses) with a mean age of 36 (standard deviation ± 9.5) years. Overall, 40.1% were adherent to existing protocols. There was no significant association between the distribution of adherence scores and sex (p = 0.319), time since completion of basic training (p = 0.595), occupational rank (p = 0.461), or age (p = 0.949). Overall, 19% felt their knowledge of infection control practices was inadequate. Those with working knowledge of infection control practices attained it mostly through informal communication (80.4%) and self-directed research (62.6%). Conclusion: New approaches to the problem of nonadherence to infection control guidelines are needed in the Caribbean. Several unique cultural, financial, and environmental factors influence adherence in this region, in contrast to conditions in developed countries. PMID:24355900

Efficiency of a cleaning protocol for the removal of enterotoxigenic Staphylococcus aureus strains in dairy plants.

PubMed

Martin, José Guilherme Prado; de Oliveira E Silva, Gabriela; da Fonseca, Carolina Rodrigues; Morales, Caio Baptista; Souza Pamplona Silva, Caroline; Miquelluti, Daniel Lima; Porto, Ernani

2016-12-05

Staphylococci are considered a major concern in dairy plants mainly due to the intensive production flow, automation of processing plants and increased demand in the microbiological quality of dairy products. This study aimed to identify S. aureus strains isolated from three Brazilian dairy plants, evaluate the influence of time, temperature and contact surface on the bacterial adhesion process, as well as the efficiency of simulated hygiene and sanitation protocol in removing adhered cells. For genotypic analyses, the presence of icaA and icaD in strains was evaluated. Adherence assays were performed in biofilm reactor, comparing the influence of 2 temperatures (5°C and 35°C), 2 surfaces (stainless steel and polypropylene) and 4 contact times (3, 6, 12h and post-sanitization). To evaluate the process effectiveness in removing adhered cells, neutral detergent and sanitizing agent based on sodium hypochlorite were used in order to simulate the situation observed in one of the dairy plants analyzed. The presence of icaA and icaD genes was determined in 75.3% and 77.6% of strains, respectively; 70.6% of isolates showed both genes, whereas 17.6% showed no genes. Genes for enterotoxin production were found in all samples, relating to SEG and SEH toxins. The number of cells adhered on both surfaces was about 3 and 6 log 10 CFU/cm 2 at temperatures of 5°C and 35°C, respectively, for most situations evaluated, with significant increase over the evaluation period. In general, the temperature of 35°C favored greater adherence of S. aureus. At 5°C, there was a considerable number of adhered cells, but in populations significantly lower than those observed at 35°C. The cleaning and sanitizing protocol was ineffective in removing adhered cells; better performance of sodium hypochlorite was observed at 5°C, which should be related to lower adherence observed at this temperature. Thus, the process was not able to reduce the number of S. aureus bacteria adhered on both surfaces to safe levels under the conditions evaluated. Copyright © 2016 Elsevier B.V. All rights reserved.

A New Lebanese Medication Adherence Scale: Validation in Lebanese Hypertensive Adults

PubMed Central

Wakim, N.; Issa, C.; Kassem, B.; Abou Jaoude, L.; Saleh, N.

2018-01-01

Background A new Lebanese scale measuring medication adherence considered socioeconomic and cultural factors not taken into account by the eight-item Morisky Medication Adherence Scale (MMAS-8). Objectives were to validate the new adherence scale and its prediction of hypertension control, compared to MMAS-8, and to assess adherence rates and factors. Methodology A cross-sectional study, including 405 patients, was performed in outpatient cardiology clinics of three hospitals in Beirut. Blood pressure was measured, a questionnaire filled, and sodium intake estimated by a urine test. Logistic regression defined predictors of hypertension control and adherence. Results 54.9% had controlled hypertension. 82.4% were adherent by the new scale, which showed good internal consistency, adequate questions (KMO coefficient = 0.743), and four factors. It predicted hypertension control (OR = 1.217; p value = 0.003), unlike MMAS-8, but the scores were correlated (ICC average measure = 0.651; p value < 0.001). Stress and smoking predicted nonadherence. Conclusion This study elaborated a validated, practical, and useful tool measuring adherence to medications in Lebanese hypertensive patients. PMID:29887993

Selective binding and lateral clustering of α5β1 and αvβ3 integrins: Unraveling the spatial requirements for cell spreading and focal adhesion assembly

PubMed Central

Schaufler, Viktoria; Czichos-Medda, Helmi; Hirschfeld-Warnecken, Vera; Neubauer, Stefanie; Rechenmacher, Florian; Medda, Rebecca; Kessler, Horst; Geiger, Benjamin; Spatz, Joachim P.; Cavalcanti-Adam, E. Ada

2016-01-01

ABSTRACT Coordination of the specific functions of α5β1 and αvβ3 integrins is crucial for the precise regulation of cell adhesion, spreading and migration, yet the contribution of differential integrin-specific crosstalk to these processes remains unclear. To determine the specific functions of αvβ3 and α5β1 integrins, we used nanoarrays of gold particles presenting immobilized, integrin-selective peptidomimetic ligands. Integrin binding to the peptidomimetics is highly selective, and cells can spread on both ligands. However, spreading is faster and the projected cell area is greater on α5β1 ligand; both depend on ligand spacing. Quantitative analysis of adhesion plaques shows that focal adhesion size is increased in cells adhering to αvβ3 ligand at 30 and 60 nm spacings. Analysis of αvβ3 and α5β1 integrin clusters indicates that fibrillar adhesions are more prominent in cells adhering to α5β1 ligand, while clusters are mostly localized at the cell margins in cells adhering to αvβ3 ligand. αvβ3 integrin clusters are more pronounced on αvβ3 ligand, though they can also be detected in cells adhering to α5β1 ligand. Furthermore, α5β1 integrin clusters are present in cells adhering to α5β1 ligand, and often colocalize with αvβ3 clusters. Taken together, these findings indicate that the activation of αvβ3 integrin by ligand binding is dispensable for initial adhesion and spreading, but essential to formation of stable focal adhesions. PMID:27003228

Glycosides derived from Hemidesmus indicus R. Br. root inhibit adherence of Salmonella typhimurium to host cells: receptor mimicry.

PubMed

Das, Sarita; Devaraj, S Niranjali

2006-09-01

For centuries, indigenous plants have been used against enteritis but their molecular targets and mode of action remain obscure. The present study was carried out to elucidate the protective and therapeutic role, if any, of glycosides from Hemidesmus indicus against S. typhimurium-induced pathogenesis. Studies were carried out in a human intestinal cell line (Int 407) and a murine macrophage cell line (P388D1) in order to evaluate its potency in local as well as systemic infections. The inhibitory role of the glycosides present in Hemidesmus indicus root extract (GHI) were tested by pre-coating the cells (both Int 407 and P388D1) with GHI prior to infection, and by neutralizing the wild-type bacteria with GHI before cell infection. In both cases, GHI protected the host cells from the cytotoxic effects of the wild S. typhimurium. This suggests that the biologically significant sugars (hexose, hexosamine, fucose and sialic acid etc) present in GHI might be mimicking host cell receptor saccharides and thereby blocking the bacterial ligands from binding to the host cells. Int 407 cells infected with wild-type bacteria had a diffused adherence pattern after 4 h incubation, but this typical character was not observed in cells infected with GHI-treated bacteria and the cells were normal in appearance at 4 h. After 18 h cells infected with wild-type bacteria were hypertrophoid with a disintegrated membrane and wrapped in a bacterial coat, whereas cells infected with treated bacteria had comparatively less morphological changes and few defective shrunken rods adhered locally. This suggests that the glycosides can change the adherence pattern of S. typhimurium from diffused to local. Treated bacteria had less adherence and invasion capability in Int 407 as well as P388D1 cells. The results show the decreased ability of adherence of GHI-treated S. typhimurium was due to a loss of surface hydrophobicity. A nonspecific binding between S. typhimurium and the glycosides was confirmed using ELISA. In summary, the glycosides of H. indicus root inhibited S. typhimurium induced pathogenesis nonspecifically, by reducing bacterial surface hydrophobicity and perhaps also by mimicking host cell receptors, thereby blocking its attachment to host cell and further pathological effects. Copyright (c) 2006 John Wiley & Sons, Ltd.

Universal test and treat is not associated with sub-optimal antiretroviral therapy adherence in rural South Africa: the ANRS 12249 TasP trial.

PubMed

Iwuji, Collins; McGrath, Nuala; Calmy, Alexandra; Dabis, Francois; Pillay, Deenan; Newell, Marie-Louise; Baisley, Kathy; Porter, Kholoud

2018-06-01

HIV treatment guidelines now recommend antiretroviral therapy (ART) initiation regardless of CD4 count to maximize benefit both for the individual and society. It is unknown whether the initiation of ART at higher CD4 counts would affect adherence levels. We investigated whether initiating ART at higher CD4 counts was associated with sub-optimal adherence (<95%) during the first 12 months of ART. A prospective cohort study nested within a two-arm cluster-randomized trial of universal test and treat was implemented from March 2012 to June 2016 to measure the impact of ART on HIV incidence in rural KwaZulu-Natal. ART was initiated regardless of CD4 count in the intervention arm and according to national guidelines in the control arm. ART adherence was measured monthly using a visual analogue scale (VAS) and pill counts (PC). HIV viral load was measured at ART initiation, three and six months, and six-monthly thereafter. We pooled data from participants in both arms and used random-effects logistic regression models to examine the association between CD4 count at ART initiation and sub-optimal adherence, and assessed if adherence levels were associated with virological suppression. Among 900 individuals who initiated ART ≥12 months before study end, median (IQR) CD4 at ART initiation was 350 cells/mm 3 (234, 503); median age was 34.6 years (IQR 27.4 to 46.4) and 71.7% were female. Adherence was sub-optimal in 14.7% of visits as measured by VAS and 20.7% by PC. In both the crude analyses and after adjusting for potential confounders, adherence was not significantly associated with CD4 count at ART initiation (adjusted OR for linear trend in sub-optimal adherence with every 100 cells/mm 3 increase in CD4 count: 1.00, 95% CI 0.95 to 1.05, for VAS, and 1.03, 95% CI 0.99 to 1.07, for PC). Virological suppression at 12 months was 97%. Optimal adherence by both measures was significantly associated with virological suppression (p < 0.001 for VAS; p = 0.006 for PC). We found no evidence that higher CD4 counts at ART initiation were associated with sub-optimal ART adherence in the first 12 months. Our findings should alleviate concerns about adherence in individuals initiating ART at higher CD4 counts, however long-term outcomes are needed. ClinicalTrials.gov NCT01509508. © 2018 The Authors. Journal of the International AIDS Society published by John Wiley & sons Ltd on behalf of the International AIDS Society.

Instructing cells with programmable peptide DNA hybrids

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

Freeman, Ronit; Stephanopoulos, Nicholas; Alvarez, Zaida

The native extracellular matrix is a space in which signals can be displayed dynamically and reversibly, positioned with nanoscale precision, and combined synergistically to control cell function. Here we describe a molecular system that can be programmed to control these three characteristics. In this approach we immobilize peptide-DNA (P-DNA) molecules on a surface through complementary DNA tethers directing cells to adhere and spread reversibly over multiple cycles. The DNA can also serve as a molecular ruler to control the distance-dependent synergy between two peptides. Finally, we use two orthogonal DNA handles to regulate two different bioactive signals, with the abilitymore » to independently up- or downregulate each over time. This enabled us to discover that neural stem cells, derived from the murine spinal cord and organized as neurospheres, can be triggered to migrate out in response to an exogenous signal but then regroup into a neurosphere as the signal is removed.« less

Instructing cells with programmable peptide DNA hybrids

DOE PAGES

Freeman, Ronit; Stephanopoulos, Nicholas; Alvarez, Zaida; ...

2017-07-10

The native extracellular matrix is a space in which signals can be displayed dynamically and reversibly, positioned with nanoscale precision, and combined synergistically to control cell function. Here we describe a molecular system that can be programmed to control these three characteristics. In this approach we immobilize peptide-DNA (P-DNA) molecules on a surface through complementary DNA tethers directing cells to adhere and spread reversibly over multiple cycles. The DNA can also serve as a molecular ruler to control the distance-dependent synergy between two peptides. Finally, we use two orthogonal DNA handles to regulate two different bioactive signals, with the abilitymore » to independently up- or downregulate each over time. This enabled us to discover that neural stem cells, derived from the murine spinal cord and organized as neurospheres, can be triggered to migrate out in response to an exogenous signal but then regroup into a neurosphere as the signal is removed.« less

Instructing cells with programmable peptide DNA hybrids

NASA Astrophysics Data System (ADS)

Freeman, Ronit; Stephanopoulos, Nicholas; Álvarez, Zaida; Lewis, Jacob A.; Sur, Shantanu; Serrano, Chris M.; Boekhoven, Job; Lee, Sungsoo S.; Stupp, Samuel I.

2017-07-01

The native extracellular matrix is a space in which signals can be displayed dynamically and reversibly, positioned with nanoscale precision, and combined synergistically to control cell function. Here we describe a molecular system that can be programmed to control these three characteristics. In this approach we immobilize peptide-DNA (P-DNA) molecules on a surface through complementary DNA tethers directing cells to adhere and spread reversibly over multiple cycles. The DNA can also serve as a molecular ruler to control the distance-dependent synergy between two peptides. Finally, we use two orthogonal DNA handles to regulate two different bioactive signals, with the ability to independently up- or downregulate each over time. This enabled us to discover that neural stem cells, derived from the murine spinal cord and organized as neurospheres, can be triggered to migrate out in response to an exogenous signal but then regroup into a neurosphere as the signal is removed.

Curli modulates adherence of Escherichia coli O157 to bovine recto-anal junction squamous epithelial cells

USDA-ARS?s Scientific Manuscript database

Our recent studies have shown that Intimin and the Locus of Enterocyte Effacement-encoded proteins do not play a role in Escherichia coli O157 (O157) adherence to the bovine recto-anal junction squamous epithelial cells (RSE) cells. Hence, to define factors that play a contributory role, we investi...

Patient and Partner Feedback Reports to Improve Statin Medication Adherence: A Randomized Control Trial.

PubMed

Reddy, Ashok; Huseman, Tiffany L; Canamucio, Anne; Marcus, Steven C; Asch, David A; Volpp, Kevin; Long, Judith A

2017-03-01

Simple nudges such as reminders and feedback reports to either a patient or a partner may facilitate improved medication adherence. To test the impact of a pill bottle used to monitor adherence, deliver a daily alarm, and generate weekly medication adherence feedback reports on statin adherence. Three-month, three-arm randomized clinical trial (ClinicalTrials.gov identifier: NCT02480530). One hundred and twenty-six veterans with known coronary artery disease and poor adherence (medication possession ratio <80 %). Patients were randomized to one of three groups: (1) a control group (n = 36) that received a pill-monitoring device with no alarms or feedback; (2) an individual feedback group (n = 36) that received a daily alarm and a weekly medication adherence feedback report; and (3) a partner feedback group (n = 54) that received an alarm and a weekly feedback report that was shared with a friend, family member, or a peer. The intervention continued for 3 months, and participants were followed for an additional 3 months after the intervention period. Adherence as measured by pill bottle. Secondary outcomes included change in LDL (mg/dl), patient activation, and social support. During the 3-month intervention period, medication adherence was higher in both feedback arms than in the control arm (individual feedback group 89 %, partner feedback group 86 %, control group 67 %; p < 0.001 and = 0.001). At 6 months, there was no difference in medication adherence between either of the feedback groups and the control (individual feedback 60 %, partner feedback 52 %, control group 54 %; p = 0.75 and 0.97). Daily alarms combined with individual or partner feedback reports improved statin medication adherence. While neither an individual feedback nor partner feedback strategy created a sustainable medication adherence habit, the intervention itself is relatively easy to implement and low cost.

Effect of bisphosphonates on macrophagic THP-1 cell survival in bisphosphonate-related osteonecrosis of the jaw (BRONJ).

PubMed

Hoefert, Sebastian; Sade Hoefert, Claudia; Munz, Adelheid; Schmitz, Inge; Grimm, Martin; Yuan, Anna; Northoff, Hinnak; Reinert, Siegmar; Alexander, Dorothea

2016-03-01

Immune deficiency and bacterial infection have been suggested to play a role in the pathophysiology of bisphosphonate-related osteonecrosis of the jaw (BRONJ). Zoledronate was previously found to promote THP-1 cell death. To examine this hypothesis with all commonly prescribed bisphosphonates, we tested the effect of (nitrogen-containing) ibandronate, risedronate, alendronate, pamidronate, and (non-nitrogen-containing) clodronate on macrophagic THP-1 cells. Activated THP-1 cells were exposed to .5 to 50 μM of nitrogen-containing bisphosphonates and .5 to 500 μM of clodronate. Cell adherence and survival were assessed in vitro using the xCELLigence real-time monitoring system. Results were confirmed histologically and verified with Live/Dead staining. All bisphosphonates inhibited THP-1 cell adherence and survival dose and time dependently, significant for zoledronate, alendronate, pamidronate, and clodronate in high concentrations (50 μM and 500 μM; P < .05). Low concentrations (0.5 μM) of risedronate, alendronate, and pamidronate prolonged the inflexion points of THP-1 cell survival compared with controls (P < .05). THP-1 cells exhibited no cytomorphologic changes at all concentrations. Commonly prescribed bisphosphonates inhibit the survival of macrophagic THP-1 cells dose-dependently without altering morphology. This may suggest a local immune dysfunction reflective of individual bisphosphonate potency leading to the pathogenesis of BRONJ. Copyright © 2016 Elsevier Inc. All rights reserved.

HABIT, a Randomized Feasibility Trial to Increase Hydroxyurea Adherence, Suggests Improved Health-Related Quality of Life in Youths with Sickle Cell Disease.

PubMed

Smaldone, Arlene; Findley, Sally; Manwani, Deepa; Jia, Haomiao; Green, Nancy S

2018-06-01

To examine the effect of a community health worker (CHW) intervention, augmented by tailored text messages, on adherence to hydroxyurea therapy in youths with sickle cell disease, as well as on generic and disease-specific health-related quality of life (HrQL) and youth-parent self-management responsibility concordance. We conducted a 2-site randomized controlled feasibility study (Hydroxyurea Adherence for Personal Best in Sickle Cell Treatment [HABIT]) with 2:1 intervention allocation. Youths and parents participated as dyads. Intervention dyads received CHW visits and text message reminders. Data were analyzed using descriptive statistics, the Wilcoxon signed-rank test, and growth models adjusting for group assignment, time, and multiple comparisons. Changes in outcomes from 0 to 6 months were compared with their respective minimal clinically important differences. A total of 28 dyads (mean age of youths, 14.3 ± 2.6 years; 50% Hispanic) participated (18 in the intervention group, 10 in the control group), with 10.7% attrition. Accounting for group assignment, time, and multiple comparisons, at 6 months intervention youths reported improved generic HrQL total score (9.8 points; 95% CI, 0.4-19.2) and Emotions subscale score (15.0 points; 95% CI, 1.6-28.4); improved disease-specific subscale scores for Worry I (30.0 points; 95% CI, 8.5-51.5), Emotions (37.0 points, 95% CI, 9.4-64.5), and Communication I (17.8 points; 95% CI, 0.5-35.1); and 3-month dyad self-management responsibility concordance (3.5 points; 95% CI, -0.2 to 7.1). There were no differences in parent proxy-reported HrQL measures at 6 months. These findings add to research examining effects of behavioral interventions on HrQL outcomes in youths with sickle cell disease. ClinicalTrials.gov: NCT02029742. Copyright © 2018 Elsevier Inc. All rights reserved.

Gammadelta receptor bearing T cells in scleroderma: enhanced interaction with vascular endothelial cells in vitro.

PubMed

Kahaleh, M B; Fan, P S; Otsuka, T

1999-05-01

In view of the documented perivascular mononuclear cell infiltration in the involved organs in scleroderma (SSc) and the reported accumulation of gammadelta-T cells in SSc skin and lung, we evaluated gammadelta-T cell interaction with endothelial cells (EC) in vitro. gammadelta- and alphabeta-T cells were isolated from BPMN of SSc patients with early diffuse disease and of matched control subjects by an immunomagnetic method after stimulation with mycobacterium lysate and interleukin-2 for 2 weeks. Lymphocyte adhesion, proliferation, and cytotoxicity to EC were investigated. SSc gammadelta-T cells adhered to cultured EC and proliferated at higher rates than control cells. Furthermore, significant EC cytotoxicity by SSc gammadelta was seen. The cytotoxicity was blocked by addition of anti-gammadelta-TCR antibody and by anti-granzyme A antibody but not by anti-MHC class I and II antibodies. Expression of granzyme A mRNA was seen in five/five SSc gammadelta-T cells and in one/five control cells. alphabeta-T cells from both SSc and control subjects were significantly less interactive with EC than gammadelta-T cells. The data demonstrate EC recognition by SSc gammadelta-T cells and propose gammadelta-T cells as a possible effector cell type in the immune pathogenesis of SSc. Copyright 1999 Academic Press.

Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) Assay: Book Chapter

EPA Science Inventory

There are thousands of environmental chemicals for which there is limited toxicological information, motivating the development and application of in vitro systems to profile the biological effects of xenobiotic exposure and predict their potential developmental hazard. An adher...

Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) assay-Book Chapter*

EPA Science Inventory

There are thousands of environmental chemicals for which there is limited toxicological information, motivating the development and application of in vitro systems to profile the biological effects of xenobiotic exposure and predict their potential developmental hazard. An adhere...

Effectiveness of Adherence Therapy for People With Schizophrenia in Turkey: A Controlled Study.

PubMed

Dikec, Gul; Kutlu, Yasemin

2016-04-01

This study used a quasi-experimental design with a pretest-posttest control group and follow-up to determine the efficacy of adherence therapy in patients with schizophrenia in Turkey. The sample of this study consisted of patients with schizophrenia (n=30). The Questionnaire Form, Medication Adherence Rating Scale, Internalized Stigma of Mental Illness Scale, and Beck Cognitive Insight Scale were used. The patients were assigned to experimental (n=15) and control (n=15) groups using the randomization method. The experimental group received adherence therapy in eight sessions. When the scores of the patients in the experimental and control groups were compared at the pretest, posttest, and 3- and 6-months follow ups, a significant difference was only found in the Medication Adherence Rating Scale posttest scores. Adherence therapy is effective in improving adherence to treatment but is not effective with regard to insight and internalized stigma in patients with schizophrenia. Copyright © 2015 Elsevier Inc. All rights reserved.

Role of parenting style in achieving metabolic control in adolescents with type 1 diabetes.

PubMed

Shorer, Maayan; David, Ravit; Schoenberg-Taz, Michal; Levavi-Lavi, Ifat; Phillip, Moshe; Meyerovitch, Joseph

2011-08-01

To examine the role of parenting style in achieving metabolic control and treatment adherence in adolescents with type 1 diabetes. Parents of 100 adolescents with type 1 diabetes completed assessments of their parenting style and sense of helplessness. Parents and patients rated patient adherence to the treatment regimen. Glycemic control was evaluated by HbA(1c) values. An authoritative paternal parenting style predicted better glycemic control and adherence in the child; a permissive maternal parenting style predicted poor adherence. A higher sense of helplessness in both parents predicted worse glycemic control and lesser adherence to treatment. Parental sense of helplessness was a significant predictor of diabetes control after correcting for other confounders (patient age, sex, and treatment method). An authoritative nonhelpless parenting style is associated with better diabetes control in adolescents. Paternal involvement is important in adolescent diabetes management. These results have implications for psychological interventions.

Chapter 17 Sterile Plate-Based Vitrification of Adherent Human Pluripotent Stem Cells and Their Derivatives Using the TWIST Method.

PubMed

Neubauer, Julia C; Stracke, Frank; Zimmermann, Heiko

2017-01-01

Due to their high biological complexity, e.g., their close cell-to-cell contacts, cryopreservation of human pluripotent stem cells with standard slow-rate protocols often is inefficient and can hardly be standardized. Vitrification that means ultrafast freezing already showed very good viability and recovery rates for this sensitive cell system, but is only applicable for low cell numbers, bears a high risk of contamination, and can hardly be implemented under GxP regulations. In this chapter, a sterile plate-based vitrification method for adherent pluripotent stem cells and their derivatives is presented based on a procedure and device for human embryonic stem cells developed by Beier et al. (Cryobiology 66:8-16, 2013). This protocol overcomes the limitations of conventional vitrification procedures resulting in the highly efficient preservation of ready-to-use adherent pluripotent stem cells with the possibility of vitrifying cells in multi-well formats for direct application in high-throughput screenings.

Directing stem cell fate on hydrogel substrates by controlling cell geometry, matrix mechanics and adhesion ligand composition.

PubMed

Lee, Junmin; Abdeen, Amr A; Zhang, Douglas; Kilian, Kristopher A

2013-11-01

There is a dynamic relationship between physical and biochemical signals presented in the stem cell microenvironment to guide cell fate determination. Model systems that modulate cell geometry, substrate stiffness or matrix composition have proved useful in exploring how these signals influence stem cell fate. However, the interplay between these physical and biochemical cues during differentiation remains unclear. Here, we demonstrate a microengineering strategy to vary single cell geometry and the composition of adhesion ligands - on substrates that approximate the mechanical properties of soft tissues - to study adipogenesis and neurogenesis in adherent mesenchymal stem cells. Cells cultured in small circular islands show elevated expression of adipogenesis markers while cells that spread in anisotropic geometries tend to express elevated neurogenic markers. Arraying different combinations of matrix protein in a myriad of 2D and pseudo-3D geometries reveals optimal microenvironments for controlling the differentiation of stem cells to these "soft" lineages without the use of media supplements. © 2013 Elsevier Ltd. All rights reserved.

Hha controls Escherichia coli O157:H7 biofilm formation by differential regulation of global transcriptional regulators FlhDC and CsgD

USDA-ARS?s Scientific Manuscript database

Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is a zoonotic pathogen that produces a broad-spectrum of diarrheal illnesses in infected humans. Although molecular mechanisms enabling EHEC O157:H7 to produce characteristic adherence on epithelial cells are well characterized, regulatory mechanisms...

Cellular internalization of polycation-coated microparticles and its dependence on their zeta potential

NASA Astrophysics Data System (ADS)

Kato, Noritaka; Kondo, Ryosuke

2018-03-01

By applying microparticles to HeLa cells, the number of particles adhered on the cell and that of the ones internalized in the cells were evaluated. Three-dimensional tomographic images of the cells with the particles were obtained by multiphoton excitation laser scanning microscopy, and the adhered and internalized particles were counted separately. When the surface charge of the particles was reversed from negative to positive by coating the particles with polycations, both numbers significantly increased owing to the electrostatic attraction between the cells and the polycation-coated particles. Four different positively charged particles were prepared using four different polycations, and the numbers of adhered and internalized particles were compared. Our results suggest that these numbers depended on the zeta potential rather than the molecular structure of the polycation.

Intact LKB1 activity is required for survival of dormant ovarian cancer spheroids.

PubMed

Peart, Teresa; Ramos Valdes, Yudith; Correa, Rohann J M; Fazio, Elena; Bertrand, Monique; McGee, Jacob; Préfontaine, Michel; Sugimoto, Akira; DiMattia, Gabriel E; Shepherd, Trevor G

2015-09-08

Metastatic epithelial ovarian cancer (EOC) cells can form multicellular spheroids while in suspension and disperse directly throughout the peritoneum to seed secondary lesions. There is growing evidence that EOC spheroids are key mediators of metastasis, and they use specific intracellular signalling pathways to control cancer cell growth and metabolism for increased survival. Our laboratory discovered that AKT signalling is reduced during spheroid formation leading to cellular quiescence and autophagy, and these may be defining features of tumour cell dormancy. To further define the phenotype of EOC spheroids, we have initiated studies of the Liver kinase B1 (LKB1)-5'-AMP-activated protein kinase (AMPK) pathway as a master controller of the metabolic stress response. We demonstrate that activity of AMPK and its upstream kinase LKB1 are increased in quiescent EOC spheroids as compared with proliferating adherent EOC cells. We also show elevated AMPK activity in spheroids isolated directly from patient ascites. Functional studies reveal that treatment with the AMP mimetic AICAR or allosteric AMPK activator A-769662 led to a cytostatic response in proliferative adherent ovarian cancer cells, but they fail to elicit an effect in spheroids. Targeted knockdown of STK11 by RNAi to reduce LKB1 expression led to reduced viability and increased sensitivity to carboplatin treatment in spheroids only, a phenomenon which was AMPK-independent. Thus, our results demonstrate a direct impact of altered LKB1-AMPK signalling function in EOC. In addition, this is the first evidence in cancer cells demonstrating a pro-survival function for LKB1, a kinase traditionally thought to act as a tumour suppressor.

N-acetylcysteine attenuates endotoxin-induced leukocyte-endothelial cell adhesion and macromolecular leakage in vivo.

PubMed

Schmidt, H; Schmidt, W; Müller, T; Böhrer, H; Gebhard, M M; Martin, E

1997-05-01

To determine the influence of N-acetylcysteine on endotoxin-induced leukocyte-endothelial cell adhesion, vascular leakage, and venular microhemodynamics. Randomized, blinded, controlled trial. Experimental laboratory. Thirty male Wistar rats. After pretreatment with N-acetylcysteine (150 mg/kg; n = 40; group A) or 0.9% saline solution (n = 10; group B) animals were given an intravenous infusion of endotoxin (Escherichia coli lipopolysaccharide 026:B6; 2 mg/kg/hr) over 120 mins. Animals in the control group (n = 10; group C) received a volume-equivalent infusion of 0.9% saline solution. Leukocyte adherence, red cell velocity (VRBC), vessel diameters, venular wall shear rate, and macromolecular leakage were determined in mesenteric postcapillary venules using in vivo videomicroscopy at baseline and at 30, 50, 90, and 120 mins after the start of the endotoxin challenge. Endotoxin exposure induced a marked increase in adherent leukocytes (group B: baseline, 391 +/- 24 cells/mm2; 120 mins, 1268 +/- 131 cells/mm2; p < .01). N-acetylcysteine pretreatment attenuated the adherence of leukocytes during endotoxemia (baseline, 366 +/- 28 cells/mm2; 120 mins, 636 +/- 49 cells/mm2; p < .01 vs. baseline; p < .01 vs. group B). Leukocyte adherence in control animals (group C) did not increase significantly. Administration of N-acetylcysteine did not influence the decrease in VRBC observed during endotoxemia. In group B1 VRBC decreased during the infusion of endotoxin from 2.0 +/- 0.2 mm/sec at baseline to 1.1 +/- 0.2 mm/ sec after 120 mins (p < .01 vs. baseline; p < .05 vs. group C), and in group A from 2.2 +/- 0.2 mm/sec to 1.1 +/- 0.1 mm/sec after 120 mins (p < .01 vs. baseline; p < .05 vs. group C). In group C, VRBC remained unchanged (baseline, 1.7 +/- 0.2 mm/sec; at 120 mins, 1.5 +/- 0.2 mm/sec). The venular diameters remained unchanged in all groups during the entire study period. After 120 mins, the venular wall shear rate decreased from 502 +/- 62 secs-1 at baseline to 272 +/- 46 sec-1 in group B (p < .01), and from 563 +/- 45 secs-1 at baseline to 283 +/- 31 secs-1 in group A (p < .01). No differences in venular wall shear rate were observed between these groups. In group C, the venular wall shear rate remained unchanged (baseline, 457 +/- 54 secs-1; at 120 mins, 409 +/- 51 secs-1). Macromolecular leakage, expressed as perivenular/intravenular fluorescence intensity after injection of fluorescence-labeled albumin, increased from 0.29 +/- 0.03 to 0.58 +/- 0.03 (p < .01) during the infusion of endotoxin in group B. In contrast, pretreatment with N-acetylcysteine diminished the extravasation of albumin (baseline, 0.27 +/- 0.01; at 120 mins, 0.37 +/- 0.02; p < .01 vs. baseline; p < .01 vs. group B). These results demonstrate that N-acetylcysteine attenuates endotoxin-induced alterations in leukocyte-endothelial cell adhesion and macromolecular leakage, suggesting N-acetylcysteine might be therapeutic in the prevention of endothelial damage in sepsis.

Control of proliferation rate of N27 dopaminergic neurons using Transcranial Magnetic Stimulation orientation

NASA Astrophysics Data System (ADS)

Meng, Yiwen; Hadimani, Ravi; Anantharam, Vellareddy; Kanthasamy, Anumantha; Jiles, David

2015-03-01

Transcranial magnetic stimulation (TMS) has been used to investigate possible treatments for a variety of neurological disorders. However, the effect that magnetic fields have on neurons has not been well documented in the literature. We have investigated the effect of different orientation of magnetic field generated by TMS coils with a monophasic stimulator on the proliferation rate of N27 neuronal cells cultured in flasks and multi-well plates. The proliferation rate of neurons would increase by exposed horizontally adherent N27 cells to a magnetic field pointing upward through the neuronal proliferation layer compared with the control group. On the other hand, proliferation rate would decrease in cells exposed to a magnetic field pointing downward through the neuronal growth layer compared with the control group. We confirmed results obtained from the Trypan-blue and automatic cell counting methods with those from the CyQuant and MTS cell viability assays. Our findings could have important implications for the preclinical development of TMS treatments of neurological disorders and represents a new method to control the proliferation rate of neuronal cells.

Psychological and Educational Intervention to Improve Tuberculosis Treatment Adherence in Ethiopia Based on Health Belief Model: A Cluster Randomized Control Trial.

PubMed

Tola, Habteyes Hailu; Shojaeizadeh, Davoud; Tol, Azar; Garmaroudi, Gholamreza; Yekaninejad, Mir Saeed; Kebede, Abebaw; Ejeta, Luche Tadesse; Kassa, Desta; Klinkenberg, Eveline

2016-01-01

Treatment non-adherence results in treatment failure, prolonged transmission of disease and emergence of drug resistance. Although the problem widely investigated, there remains an information gap on the effectiveness of different methods to improve treatment adherence and the predictors of non-adherence in resource limited countries based on theoretical models. This study aimed to evaluate the impact of psychological counseling and educational intervention on tuberculosis (TB) treatment adherence based on Health Belief Model (HBM). A cluster randomized control trial was conducted in Addis Ababa from May to December, 2014. Patients were enrolled into study consecutively from 30 randomly selected Health Centers (HCs) (14 HCs intervention and 16 HCs control groups). A total of 698 TB patients, who were on treatment for one month to two months were enrolled. A structured questionnaire was administered to both groups of patients at baseline and endpoint of study. Control participants received routine directly-observed anti-TB therapy and the intervention group additionally received combined psychological counseling and adherence education. Treatment non-adherence level was the main outcome of the study, and multilevel logistic regression was employed to assess the impact of intervention on treatment adherence. At enrollment, the level of non-adherence among intervention (19.4%) and control (19.6%) groups was almost the same. However, after intervention, non-adherence level decreased among intervention group from 19.4 (at baseline) to 9.5% (at endpoint), while it increased among control group from 19.4% (baseline) to 25.4% (endpoint). Psychological counseling and educational interventions resulted in significant difference with regard to non-adherence level between intervention and control groups (Adjusted OR = 0.31, 95% Confidence Interval (CI) (0.18-0.53), p < 0.001)). Psychological counseling and educational interventions, which were guided by HBM, significantly decreased treatment non-adherence level among intervention group. Provision of psychological counseling and health education to TB patients who are on regular treatment is recommended. This could be best achieved if these interventions are guided by behavioral theories and incorporated into the routine TB treatment strategy. Pan African Clinical Trials Registry PACTR201506001175423.

Culture on 3D Chitosan-Hyaluronic Acid Scaffolds Enhances Stem Cell Marker Expression and Drug Resistance in Human Glioblastoma Cancer Stem Cells.

PubMed

Wang, Kui; Kievit, Forrest M; Erickson, Ariane E; Silber, John R; Ellenbogen, Richard G; Zhang, Miqin

2016-12-01

The lack of in vitro models that support the growth of glioblastoma (GBM) stem cells (GSCs) that underlie clinical aggressiveness hinders developing new, effective therapies for GBM. While orthotopic patient-derived xenograft models of GBM best reflect in vivo tumor behavior, establishing xenografts is a time consuming, costly, and frequently unsuccessful endeavor. To address these limitations, a 3D porous scaffold composed of chitosan and hyaluronic acid (CHA) is synthesized. Growth and expression of the cancer stem cell (CSC) phenotype of the GSC GBM6 taken directly from fresh xenogratfs grown on scaffolds or as adherent monolayers is compared. While 2D adherent cultures grow as monolayers of flat epitheliod cells, GBM6 cells proliferate within pores of CHA scaffolds as clusters of self-adherent ovoid cells. Growth on scaffolds is accompanied by greater expression of genes that mediate epithelial-mesenchymal transition and maintain a primitive, undifferentiated phenotype, hallmarks of CSCs. Scaffold-grown cells also display higher expression of genes that promote resistance to hypoxia-induced oxidative stress. In accord, scaffold-grown cells show markedly greater resistance to clinically utilized alkylating agents compared to adherent cells. These findings suggest that our CHA scaffolds better mimic in vivo biological and clinical behavior and provide insights for developing novel individualized treatments. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Functionalized Iron Oxide Nanoparticles for Controlling the Movement of Immune Cells

PubMed Central

White, Ethan E; Pai, Alex; Weng, Yiming; Suresh, Anil K.; Van Haute, Desiree; Pailevanian, Torkom; Alizadeh, Darya; Hajimiri, Ali; Badie, Behnam; Berlin, Jacob M.

2015-01-01

Immunotherapy is currently being investigated for the treatment of many diseases, including cancer. The ability to control the location of immune cells during or following activation would represent a powerful new technique for this field. Targeted magnetic delivery is emerging as a technique for controlling cell movement and localization. Here we show that this technique can be extended to microglia, the primary phagocytic immune cells in the central nervous system. The magnetized microglia were generated by loading the cells with iron oxide nanoparticles functionalized with CpG oligonucleotides, serving as a proof of principle that nanoparticles can be used to both deliver an immunostimulatory cargo to cells and to control the movement of the cells. The nanoparticle-oligonucleotide conjugates are efficiently internalized, non-toxic, and immunostimulatory. We demonstrate that the in vitro migration of the adherent, loaded microglia can be controlled by an external magnetic field and that magnetically-induced migration is non-cytotoxic. In order to capture video of this magnetically-induced migration of loaded cells, a novel 3D-printed “cell box” was designed to facilitate our imaging application. Analysis of cell movement velocities clearly demonstrate increased cell velocities toward the magnet. These studies represent the initial step towards our final goal of using nanoparticles to both activate immune cells and to control their trafficking within the diseased brain. PMID:25848983

Functionalized iron oxide nanoparticles for controlling the movement of immune cells.

PubMed

White, Ethan E; Pai, Alex; Weng, Yiming; Suresh, Anil K; Van Haute, Desiree; Pailevanian, Torkom; Alizadeh, Darya; Hajimiri, Ali; Badie, Behnam; Berlin, Jacob M

2015-05-07

Immunotherapy is currently being investigated for the treatment of many diseases, including cancer. The ability to control the location of immune cells during or following activation would represent a powerful new technique for this field. Targeted magnetic delivery is emerging as a technique for controlling cell movement and localization. Here we show that this technique can be extended to microglia, the primary phagocytic immune cells in the central nervous system. The magnetized microglia were generated by loading the cells with iron oxide nanoparticles functionalized with CpG oligonucleotides, serving as a proof of principle that nanoparticles can be used to both deliver an immunostimulatory cargo to cells and to control the movement of the cells. The nanoparticle-oligonucleotide conjugates are efficiently internalized, non-toxic, and immunostimulatory. We demonstrate that the in vitro migration of the adherent, loaded microglia can be controlled by an external magnetic field and that magnetically-induced migration is non-cytotoxic. In order to capture video of this magnetically-induced migration of loaded cells, a novel 3D-printed "cell box" was designed to facilitate our imaging application. Analysis of cell movement velocities clearly demonstrate increased cell velocities toward the magnet. These studies represent the initial step towards our final goal of using nanoparticles to both activate immune cells and to control their trafficking within the diseased brain.

Controller adherence following hospital discharge in high risk children: A pilot randomized trial of text message reminders.

PubMed

Kenyon, Chén C; Gruschow, Siobhan M; Quarshie, William O; Griffis, Heather; Leach, Michelle C; Zorc, Joseph J; Bryant-Stephens, Tyra C; Miller, Victoria A; Feudtner, Chris

2018-02-13

To assess the feasibility of a mobile health, inhaled corticosteroid (ICS) adherence reminder intervention and to characterize adherence trajectories immediately following severe asthma exacerbation in high-risk urban children with persistent asthma. Children aged 2-13 with persistent asthma were enrolled in this pilot randomized controlled trial during an asthma emergency department (ED) visit or hospitalization. Intervention arm participants received daily text message reminders for 30 days, and both arms received electronic sensors to measure ICS use. Primary outcomes were feasibility of sensor use and text message acceptability. Secondary outcomes included adherence to prescribed ICS regimen and 30-day adherence trajectories. Group-based trajectory modeling was used to examine adherence trajectories. Forty-one participants (mean age 5.9) were randomized to intervention (n = 21) or control (n = 20). Overall, 85% were Black, 88% had public insurance, and 51% of the caregivers had a high school education or less. Thirty-two participant families (78%) transmitted medication adherence data; of caregivers who completed the acceptability survey, 25 (96%) chose to receive daily reminders beyond that study interval. Secondary outcome analyses demonstrated similar average daily adherence between groups (intervention = 36%; control = 32%, P = 0.73). Three adherence trajectories were identified with none ever exceeding 80% adherence. Within a high-risk pediatric cohort, electronic monitoring of ICS use and adherence reminders delivered via text message were feasible for most participants, but there was no signal of effect. Adherence trajectories following severe exacerbation were suboptimal, demonstrating an important opportunity for asthma care improvement.

IgG1 antimycobacterial antibodies can reverse the inhibitory effect of pentoxifylline on tumour necrosis factor alpha (TNF-alpha) secreted by mycobacterial antigen-stimulated adherent cells.

PubMed

Thakurdas, S M; Hasan, Z; Hussain, R

2004-05-01

Chronic inflammation associated with cachexia, weight loss, fever and arthralgia is the hallmark of advanced mycobacterial diseases. These symptoms are attributed to the chronic stimulation of tumour necrosis factor (TNF)-alpha. Mycobacterial components directly stimulate adherent cells to secrete TNF-alpha. We have shown recently that IgG1 antimycobacterial antibodies play a role in augmenting TNF-alpha in purified protein derivative (PPD)-stimulated adherent cells from non-BCG-vaccinated donors. We now show that IgG1 antibodies can also augment TNF-alpha expression in stimulated adherent cells obtained from BCG-vaccinated donors and this augmentation is not linked to interleukin (IL)-10 secretion. In addition IgG1 antimycobacterial antibodies can reverse the effect of TNF-alpha blockers such as pentoxifylline and thalidomide. These studies therefore have clinical implications for anti-inflammatory drug treatments which are used increasingly to alleviate symptoms associated with chronic inflammation.

A comparison of human and porcine acellularized dermis: interactions with human fibroblasts in vitro.

PubMed

Armour, Alexis D; Fish, Joel S; Woodhouse, Kimberly A; Semple, John L

2006-03-01

Dermal substitutes derived from xenograft materials require elaborate processing at a considerable cost. Acellularized porcine dermis is a readily available material associated with minimal immunogenicity. The objective of this study was to evaluate acellularized pig dermis as a scaffold for human fibroblasts. In vitro methods were used to evaluate fibroblast adherence, proliferation, and migration on pig acellularized dermal matrix. Acellular human dermis was used as a control. Pig acellularized dermal matrix was found to be inferior to human acellularized dermal matrix as a scaffold for human fibroblasts. Significantly more samples of human acellularized dermal matrix (83 percent, n = 24; p < 0.05) demonstrated fibroblast infiltration below the cell-seeded surface than pig acellularized dermal matrix (31 percent, n = 49). Significantly more (p < 0.05) fibroblasts infiltrated below the surface of human acellularized dermal matrix (mean, 1072 +/- 80 cells per section; n = 16 samples) than pig acellularized dermal matrix (mean, 301 +/- 48 cells per section; n = 16 samples). Fibroblasts migrated significantly less (p < 0.05) distance from the cell-seeded pig acellularized dermal matrix surface than in the human acellularized dermal matrix (78.8 percent versus 38.3 percent cells within 150 mum from the surface, respectively; n = 5). Fibroblasts proliferated more rapidly (p < 0.05) on pig acellularized dermal matrix (n = 9) than on the human acellularized dermal matrix (7.4-fold increase in cell number versus 1.8-fold increase, respectively; n = 9 for human acellularized dermal matrix). There was no difference between the two materials with respect to fibroblast adherence (8120 versus 7436 average adherent cells per section, for pig and human acellularized dermal matrix, respectively; n = 20 in each group; p > 0.05). Preliminary findings suggest that substantial differences may exist between human fibroblast behavior in cell-matrix interactions of porcine and human acellularized dermis.

Non-adherence in children with asthma reviewed: The need for improvement of asthma care and medical education.

PubMed

Klok, Ted; Kaptein, Adrian A; Brand, Paul L P

2015-05-01

Adherence to daily inhaled corticosteroid therapy is a key determinant of asthma control. Therefore, improving adherence to inhaled corticosteroids is the most effective method through which healthcare providers can help children with uncontrolled asthma. However, identifying non-adherent patients is difficult, and electronic monitoring is the only reliable method to assess adherence. (Non-)adherence is a complex behavioural process influenced by many interacting factors. Intentional barriers to adherence are common; driven by illness perceptions and medication beliefs, patients and parents deliberately choose not to follow the doctor's recommendations. Common non-intentional barriers are related to family routines, child-raising issues, and to social issues such as poverty. Effective interventions improving adherence are complex, because they take intentional and non-intentional barriers to adherence into account. There is evidence that comprehensive, guideline-based asthma self-management programmes can be successful, with excellent adherence and good asthma control. Patient-centred care focused on healthcare provider-patient/parent collaboration is the key factor determining the success of guided self-management programmes. Such care should focus on shared decision-making as this has been shown to improve adherence and healthcare outcomes. Current asthma care falls short because many physicians fail to adhere to asthma guidelines in their diagnostic approach and therapeutic prescriptions, and because of the lack of application of patient-centred health care. Increased awareness of the importance of patient-centred communication and increased training in patient-centred communication skills of undergraduates and experienced attending physicians are needed to improve adherence to daily controller therapy and asthma control in children with asthma. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Impact of tailored patient education on adherence of patients with chronic myeloid leukaemia to tyrosine kinase inhibitors: a randomized multicentre intervention study.

PubMed

Kekäle, Meri; Söderlund, Tim; Koskenvesa, Perttu; Talvensaari, Kimmo; Airaksinen, Marja

2016-09-01

The aim of this study was to evaluate the influence of tailored patient education on adherence to tyrosine kinase inhibitor medication among patients with chronic myeloid leukaemia. Management of chronic myeloid leukaemia has changed dramatically during the last decade. While medication adherence is crucial to clinical response, little is known about how to improve patients' adherence. Randomized multicentre intervention study. The study was conducted between June 2012-August 2014. Eighty-six patients with chronic myeloid leukaemia who had been on tyrosine kinase inhibitor medication for at least six months from eight hospitals were randomized into intervention and control groups. Intervention combined nurse-conducted medication counselling, an information booklet, video and website and text message reminders. Patients were interviewed to assess medication adherence using Morisky's 8-Item Medication Adherence Scale at baseline and nine months. Medication adherence improved with the adherence aids used. At nine months, 51% of patients were highly adherent in the intervention group, compared with 21% in the control group. Adherence improved for a higher proportion of patients in the intervention group than the control group (49% vs. 18%). Morisky's score decreased in almost half of control group cases. Patients were most satisfied with face-to-face counselling (86%) and the information booklet (83%) and least satisfied with text messages (9%). Tailored patient education improved the medication adherence of patients with chronic myeloid leukaemia. Without this, adherence behaviour tended to decline. Personal communication with a nurse proved to be an essential part of adherence support and should not be ignored. © 2016 John Wiley & Sons Ltd.

Poor medication adherence to bisphosphonates and high self-perception of aging in elderly female patients with osteoporosis.

PubMed

Wu, X; Wei, D; Sun, B; Wu, X N

2016-10-01

Non-adherence to bisphosphonates exposes the elderly female osteoporosis patients to an increased risk of fracture. This was one of the first studies to explore the relationship between medication adherence and self-perception of aging. Feelings of lacking control and expectations for negative events, beliefs of illness's chronic duration nature, and its linkage with aging were associated with of poor medication adherence. To examine the relationship between medication adherence to bisphosphonates and self-perception of aging in elderly female patients with osteoporosis. This was a cross-sectional survey. A convenience sample of 245 elderly female patients with osteoporosis prescribed regular oral bisphosphonate therapy was recruited from three tertiary hospitals in China. Sociodemographic and osteoporosis-related data, Morisky Medication Adherence Scale-8 (MMAS-8) and Aging Perceptions Questionnaire (APQ) data were collected. Mean adherence score measured by MMAS-8 was 4.46(SD = 1.91; range, 0.25-7.00). Percentages of good and poor adherence were 28.6 and 71.4 %, which showed a poor medication adherence. Six domains of APQ statistically significantly associated with medication adherence. Interestingly, with control of age, educational status, marital status, and symptoms accompanying osteoporosis as covariates in the multivariate linear regression model, the effects of three domains disappeared. Significantly, worse adherence was observed in those patients who had higher feelings of lack of control, more expectations for negative events, more beliefs of osteoporosis's chronic duration nature and its linkage with aging. We conclude that feelings of lacking control, expectations for negative events, beliefs of illness's chronic duration nature, and its linkage with aging were associated with poor medication adherence in elderly female patients with osteoporosis. Concerns about self-perception of aging need to be addressed in order to improve medication adherence.

Specialized activities and expression differences for Clostridium thermocellum biofilm and planktonic cells

DOE PAGES

Dumitrache, Alexandru; Klingeman, Dawn M.; Natzke, Jace; ...

2017-02-27

Clostridium thermocellum forms biofilms adherent to lignocellulosic feedstock in a typical continuous cell-monolayer to efficiently break down and uptake cellulose hydrolysates. The sessile cells of biofilms may revert to non-adherent planktonic cells through generation of offspring cells or microenvironment constraints such as limited surface area. These interdependent cell populations co-exist and have different contributions to culture activity and growth. Here, we developed a novel bioreactor design to rapidly harvest sessile and planktonic cell populations for omics studies. In RNA-seq analyses, within 3299 protein coding genes, 59% (or 1958 genes) were differentially expressed with a minimum two-fold change between the twomore » cell populations isolated simultaneously at high culture activity. Furthermore, sessile cells had definitive greater expression of genes involved in catabolism of carbohydrates by glycolysis and pyruvate fermentation, ATP generation by proton gradient, the anabolism of proteins and lipids and cellular functions critical for cell division; planktonic cells had notably higher gene expression for flagellar motility and chemotaxis, cellulosomal cellulases and anchoring scaffoldins, and a range of stress induced homeostasis mechanisms such as oxidative stress protection by antioxidants and flavoprotein co-factors, methionine repair, Fe-S cluster assembly and repair in redox proteins, cell growth control through tRNA thiolation, recovery of damaged DNA by nucleotide excision repair and removal of terminal proteins by proteases. Our knowledge of these cellular adaptations will aid the engineering of industrially relevant strains for consolidated bioprocessing of solid lignocellulosic biomass« less

Specialized activities and expression differences for Clostridium thermocellum biofilm and planktonic cells

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

Dumitrache, Alexandru; Klingeman, Dawn M.; Natzke, Jace

Clostridium thermocellum forms biofilms adherent to lignocellulosic feedstock in a typical continuous cell-monolayer to efficiently break down and uptake cellulose hydrolysates. The sessile cells of biofilms may revert to non-adherent planktonic cells through generation of offspring cells or microenvironment constraints such as limited surface area. These interdependent cell populations co-exist and have different contributions to culture activity and growth. Here, we developed a novel bioreactor design to rapidly harvest sessile and planktonic cell populations for omics studies. In RNA-seq analyses, within 3299 protein coding genes, 59% (or 1958 genes) were differentially expressed with a minimum two-fold change between the twomore » cell populations isolated simultaneously at high culture activity. Furthermore, sessile cells had definitive greater expression of genes involved in catabolism of carbohydrates by glycolysis and pyruvate fermentation, ATP generation by proton gradient, the anabolism of proteins and lipids and cellular functions critical for cell division; planktonic cells had notably higher gene expression for flagellar motility and chemotaxis, cellulosomal cellulases and anchoring scaffoldins, and a range of stress induced homeostasis mechanisms such as oxidative stress protection by antioxidants and flavoprotein co-factors, methionine repair, Fe-S cluster assembly and repair in redox proteins, cell growth control through tRNA thiolation, recovery of damaged DNA by nucleotide excision repair and removal of terminal proteins by proteases. Our knowledge of these cellular adaptations will aid the engineering of industrially relevant strains for consolidated bioprocessing of solid lignocellulosic biomass« less

The Effect of Social Support on Glycemic Control in Patients with Type 2 Diabetes Mellitus: The Mediating Roles of Self-Efficacy and Adherence

PubMed Central

Shao, Yechang; Liang, Lu; Shi, Linjing; Yu, Shouyi

2017-01-01

Ample evidence suggests that social support, self-efficacy, and adherence significantly, independently, and together affect glycemic control in patients with type 2 diabetes mellitus (T2DM), but the pathway from social support to glycemic control remains unclear. This study hypothesized that the effect of social support on glycemic control was mediated sequentially by self-efficacy and adherence. Patients with T2DM were recruited from two hospitals in Guangzhou, China, from January 1 to July 31, 2014, and their sociodemographic clinical data and their assessments on social support, self-efficacy, and adherence were obtained from medical records and self-completed questionnaires. Of the 532 patients who participated, 35% achieved glycemic control (i.e., HbA1c < 7%). Social support, self-efficacy, and adherence had significant correlations with each other and with glycemic control (P < 0.05). Regression analyses and structural equation modeling showed that better social support was associated to better patient self-efficacy, which, in turn, was associated with better medical adherence, which was associated with improved glycemic control, and the relationship between social support and glycemic control was sequentially and completely mediated by self-efficacy and adherence. The five goodness-of-fit indices confirmed that our data fitted the hypothesized pathway model strongly. PMID:28626769

Bioreactor Expansion of Skin-Derived Precursor Schwann Cells.

PubMed

Walsh, Tylor; Biernaskie, Jeff; Midha, Rajiv; Kallos, Michael S

2016-01-01

Scaling up the production of cells in a culture process is a critical step when trying to develop cell-based regenerative therapies. Static cultures often cannot be easily scaled up to clinically relevant cell numbers. Alternatively, bioreactors offer a highly valuable means to develop a clinical-ready process. To culture adherent cells in suspension, such as skin-derived precursor Schwann cells (SKP-SCs), microcarriers need to be used. Microcarriers are small spherical beads suspended within the vessel that allow for higher growth surface area to volume ratio. Here we describe the procedure of combining microcarriers with the controllability of bioreactors to generate higher cell densities in smaller reactor volumes leading to a more efficient and cost-effective cell production for applications in regenerative medicine.

Adherence to hydroxyurea medication by children with sickle cell disease (SCD) using an electronic device: a feasibility study.

PubMed

Inoue, Susumu; Kodjebacheva, Gergana; Scherrer, Tammy; Rice, Gary; Grigorian, Matthew; Blankenship, Jeremy; Onwuzurike, Nkechi

2016-08-01

Adherence to hydroxyurea (HU) is a significant modifying factor in sickle cell vaso-occlusive pain. We conducted a study using an electronic medication container-monitor-reminder device (GlowCap™) to track adherence and determine whether use of this device affected rates of HU adherence. Subjects were regular attendees to our clinic. They were given a 37-item questionnaire and were asked to use a GlowCap containing HU. When the device cap is opened, it makes a remote "medication taken" record. The device also provides usage reminder in the form of lights and alarm sounds if the cap opening is delayed. Nineteen subjects participated in the survey, and 17 in the intervention phase. Of the 17, 12 had reliable adherence data. Seventeen caregivers of patients and two patients completed the survey. Two most common barriers to adherence identified were lack of reminders and absence of medicine home delivery. The intervention component of this study, which used both the electronic (GlowCap) method and medication possession ratio showed that the median adherence rate for the 12 patients evaluated was 85 %. The GlowCap device accurately kept a record of adherence rates. This device may be an effective tool for increasing HU medication adherence.

The soluble extracellular domain of E-cadherin interferes with EPEC adherence via interaction with the Tir:intimin complex.

PubMed

Login, Frédéric H; Jensen, Helene H; Pedersen, Gitte A; Amieva, Manuel R; Nejsum, Lene N

2018-06-19

Enteropathogenic Escherichia coli (EPEC) causes watery diarrhea when colonizing the surface of enterocytes. The translocated intimin receptor (Tir):intimin receptor complex facilitates tight adherence to epithelial cells and formation of actin pedestals beneath EPEC. We found that the host cell adherens junction protein E-cadherin (Ecad) was recruited to EPEC microcolonies. Live-cell and confocal imaging revealed that Ecad recruitment depends on, and occurs after, formation of the Tir:intimin complex. Combinatorial binding experiments using wild-type EPEC, isogenic mutants lacking Tir or intimin, and E. coli expressing intimin showed that the extracellular domain of Ecad binds the bacterial surface in a Tir:intimin-dependent manner. Finally, addition of the soluble extracellular domain of Ecad to the infection medium or depletion of Ecad extracellular domain from the cell surface reduced EPEC adhesion to host cells. Thus, the soluble extracellular domain of Ecad may be used in the design of intervention strategies targeting EPEC adherence to host cells.-Login, F. H., Jensen, H. H., Pedersen, G. A., Amieva, M. R., Nejsum, L. N. The soluble extracellular domain of E-cadherin interferes with EPEC adherence via interaction with the Tir:intimin complex.

Fractalkine and CX3CR1 Mediate a Novel Mechanism of Leukocyte Capture, Firm Adhesion, and Activation under Physiologic Flow

PubMed Central

Fong, Alan M.; Robinson, Lisa A.; Steeber, Douglas A.; Tedder, Thomas F.; Yoshie, Osamu; Imai, Toshio; Patel, Dhavalkumar D.

1998-01-01

Leukocyte migration into sites of inflammation involves multiple molecular interactions between leukocytes and vascular endothelial cells, mediating sequential leukocyte capture, rolling, and firm adhesion. In this study, we tested the role of molecular interactions between fractalkine (FKN), a transmembrane mucin-chemokine hybrid molecule expressed on activated endothelium, and its receptor (CX3CR1) in leukocyte capture, firm adhesion, and activation under physiologic flow conditions. Immobilized FKN fusion proteins captured resting peripheral blood mononuclear cells at physiologic wall shear stresses and induced firm adhesion of resting monocytes, resting and interleukin (IL)-2–activated CD8+ T lymphocytes and IL-2–activated NK cells. FKN also induced cell shape change in firmly adherent monocytes and IL-2–activated lymphocytes. CX3CR1-transfected K562 cells, but not control K562 cells, firmly adhered to FKN-expressing ECV-304 cells (ECV-FKN) and tumor necrosis factor α–activated human umbilical vein endothelial cells. This firm adhesion was not inhibited by pertussis toxin, EDTA/EGTA, or antiintegrin antibodies, indicating that the firm adhesion was integrin independent. In summary, FKN mediated the rapid capture, integrin-independent firm adhesion, and activation of circulating leukocytes under flow. Thus, FKN and CX3CR1 mediate a novel pathway for leukocyte trafficking. PMID:9782118

Label-free investigation of the effects of lithium niobate polarization on cell adhesion

NASA Astrophysics Data System (ADS)

Mandracchia, B.; Gennari, O.; Paturzo, M.; Grilli, S.; Ferraro, P.

2017-06-01

The determination of contact area is pivotal to understand how biomaterials properties influence cell adhesion. In particular, the influence of surface charges is well-known but still controversial, especially when new functional materials and methods are introduced. Here, we use for the first time Holographic Total Internal Reflection Microscopy (HoloTIRM) to study the influence of the spontaneous polarization of ferroelectric lithium niobate (LN) on the adhesion properties of fibroblast cells. The selective illumination of a very thin region directly above the substrate, achieved by Total Internal Reflection, provides high-contrast images of the contact regions. Holographic recording, on the other hand, allows for label-free quantitative phase imaging of the contact areas between cells and LN. Phase signal is more sensitive in the first 100nm and, thus more reliable in order to locate focal contacts. This work shows that cells adhering on negatively polarized LN present a significant increase of the contact area in comparison with cells adhering on the positively polarized LN substrate, as well as an intensification of contact vicinity. This confirms the potential of LN as a platform for investigating the role of charges on cellular processes. The similarity of cell adhesion behavior on negatively polarized LN and glass control also confirms the possibility to use LN as an active substrate without impairing cell behavior.

Association between dispensing channel and medication adherence among medicare beneficiaries taking medications to treat diabetes, high blood pressure, or high blood cholesterol.

PubMed

Iyengar, Reethi N; Balagere, Dhanur S; Henderson, Rochelle R; LeFrancois, Abbey L; Rabbitt, Rebecca M; Frazee, Sharon Glave

2014-08-01

Medication adherence, defined as taking medications as prescribed, is a key component in controlling disease progression and managing chronic illnesses such as diabetes, hypertension, and high blood cholesterol. These diseases constitute 3 of the top 5 most prevalent conditions among Medicare beneficiaries, warranting further attention to find ways to promote better medication adherence. The scientific literature has established the clinical and financial benefits of medication adherence and the role of dispensing channel in impacting adherence to medications. However, a common limitation in channel-adherence studies is the failure to control for healthy adherer effect (HAE), referring to individuals who are likely to engage proactively in activities that improve their adherence. Healthier individuals may choose the home-delivery channel to ensure continuity in their medication regimens and to minimize obstacles to adherence, such as inadequate access, inconvenience, and financial concerns. Thus, better medication adherence in home delivery may reflect healthier patients' predisposition to self-select for home delivery options. To accurately attribute the impact of dispensing channel on adherence, research would need to control for bias from a patient's predisposition to be adherent.  To examine the association of pharmacy dispensing channel (home delivery or retail pharmacy) with medication adherence for Medicare Part D beneficiaries taking medications for diabetes, hypertension, or high blood cholesterol, while controlling for low-income subsidy status, differences in days supply, and prior adherence behavior (PAB) as a way to partly control for HAE. A retrospective analysis using de-identified pharmacy claims data from a large national pharmacy benefits manager between October 2010 and December 2012. Continuously eligible Medicare Part D beneficiaries (Medicare Advantage and prescription drug plans participants only) aged 65 years or older who had an antidiabetic, antihypertensive, or antihyperlipidemic prescription claim between October and December 2010, were identified and followed for the next 2 years. Those enrolled in a home delivery auto refill program were excluded from this analysis. Multivariate logistic regression was used to evaluate the impact of dispensing channel on medication adherence, controlling for differences in demographics, low-income subsidy status, disease burden, and drug-use pattern. Patients with a proportion of days covered of ≥ 80% were considered to be adherent. The analysis controlled for PAB by using patients' adherence status in the year 2011.  The final analytical samples consisted of 150,389 diabetic patients, 615,618 hypertension patients, and 358,795 high blood cholesterol patients. The adjusted odds of being adherent for beneficiaries using home delivery were 1.25 times higher (CI = 1.20-1.30) for diabetes medications, 1.29 times higher (CI = 1.27-1.32) for hypertension medications, and 1.26 times higher (CI = 1.23-1.29) for high blood cholesterol medications, compared with beneficiaries using retail channels to obtain their prescriptions. PAB was the strongest contributor to the odds of a patient being adherent across all 3 therapy classes, ranging from odds ratio of 4.48 to 8.09.  After excluding patients who received any prescriptions via home delivery auto refill programs and controlling for PAB, differences in days supply, low-income subsidy status, demographics, and disease burden, Medicare beneficiaries who use home delivery for antidiabetics, antihypertensives, or antihyperlipidemics have a greater likelihood of being adherent than patients who fill their prescriptions at retail. The results of this study provide evidence that where medications are received may impact adherence, even when controlling for PAB. Use of the home delivery dispensing channel may be an effective method to improve adherence for Medicare beneficiaries.

Medication adherence among hypertensive patients of primary health clinics in Malaysia

PubMed Central

Ramli, Azuana; Ahmad, Nur Sufiza; Paraidathathu, Thomas

2012-01-01

Purpose Poor adherence to prescribed medications is a major cause for treatment failure, particularly in chronic diseases such as hypertension. This study was conducted to assess adherence to medications in patients undergoing hypertensive treatment in the Primary Health Clinics of the Ministry of Health in Malaysia. Factors affecting adherence to medications were studied, and the effect of nonadherence to blood pressure control was assessed. Patients and methods This was a cross-sectional study to assess adherence to medications by adult patients undergoing hypertensive treatment in primary care. Adherence was measured using a validated survey form for medication adherence consisting of seven questions. A retrospective medication record review was conducted to collect and confirm data on patients’ demographics, diagnosis, treatments, and outcomes. Results Good adherence was observed in 53.4% of the 653 patients sampled. Female patients were found to be more likely to adhere to their medication regime, compared to their male counterparts (odds ratio 1.46 [95% confidence intervals [CI]: 1.05–2.04; P < 0.05]). Patients in the ethnic Chinese were twice as likely (95% CI: 1.14–3.6; P < 0.05) to adhere, compared to those in the Indian ethnic group. An increase in the score for medicine knowledge was also found to increase the odds of adherence. On the other hand, increasing the number of drugs the patient was taking and the daily dose frequencies of the medications prescribed were found to negatively affect adherence. Blood pressure control was also found to be worse in noncompliers. Conclusion The medication adherence rate was found to be low among primary care hypertensive patients. A poor adherence rate was found to negatively affect blood pressure control. Developing multidisciplinary intervention programs to address the factors identified is necessary to improve adherence and, in turn, to improve blood pressure control. PMID:22969292

Enhanced differentiation potential of human amniotic mesenchymal stromal cells by using three-dimensional culturing.

PubMed

Lin, Xue; Li, Hao Yu; Chen, Lian Feng; Liu, Bo Jiang; Yao, Yian; Zhu, Wen Ling

2013-06-01

The therapeutic potential of human amniotic mesenchymal stromal cells (hAMSCs) remains limited because of their differentiation towards mesenchymal stem cells (MSCs) following adherence. The aim of this study was to develop a three-dimensional (3-D) culture system that would permit hAMSCs to differentiate into cardiomyocyte-like cells. hAMSCs were isolated from human amnions of full-term births collected after Cesarean section. Immunocytochemistry, immunofluorescence and flow cytometry analyses were undertaken to examine hAMSC marker expression for differentiation status after adherence. Membrane currents were determined by patch clamp analysis of hAMSCs grown with or without cardiac lysates. Freshly isolated hAMSCs were positive for human embryonic stem-cell-related markers but their marker profile significantly shifted towards that of MSCs following adherence. hAMSCs cultured in the 3-D culture system in the presence of cardiac lysate expressed cardiomyocyte-specific markers, in contrast to those maintained in standard adherent cultures or those in 3-D cultures without cardiac lysate. hAMSCs cultured in 3-D with cardiac lysate displayed a cardiomyocyte-like phenotype as observed by membrane currents, including a calcium-activated potassium current, a delayed rectifier potassium current and a Ca(2+)-resistant transient outward K(+) current. Thus, although adherence limits the potential of hAMSCs to differentiate into cardiomyocyte-like cells, the 3-D culture of hAMSCs represents a more effective method of their culture for use in regenerative medicine.

Silver colloidal nanoparticles: antifungal effect against adhered cells and biofilms of Candida albicans and Candida glabrata.

PubMed

Monteiro, D R; Gorup, L F; Silva, S; Negri, M; de Camargo, E R; Oliveira, R; Barbosa, D B; Henriques, M

2011-08-01

The aim of this study was to evaluate the effect of silver nanoparticles (SN) against Candida albicans and Candida glabrata adhered cells and biofilms. SN (average diameter 5 nm) were synthesized by silver nitrate reduction with sodium citrate and stabilized with ammonia. Minimal inhibitory concentration (MIC) tests were performed for C. albicans (n = 2) and C. glabrata (n = 2) grown in suspension following the Clinical Laboratory Standards Institute microbroth dilution method. SN were applied to adhered cells (2 h) or biofilms (48 h) and after 24 h of contact their effect was assessed by enumeration of colony forming units (CFUs) and quantification of total biomass (by crystal violet staining). The MIC results showed that SN were fungicidal against all strains tested at very low concentrations (0.4-3.3 μg ml(-1)). Furthermore, SN were more effective in reducing biofilm biomass when applied to adhered cells (2 h) than to pre-formed biofilms (48 h), with the exception of C. glabrata ATCC, which in both cases showed a reduction ∼90%. Regarding cell viability, SN were highly effective on adhered C. glabrata and respective biofilms. On C. albicans the effect was not so evident but there was also a reduction in the number of viable biofilm cells. In summary, SN may have the potential to be an effective alternative to conventional antifungal agents for future therapies in Candida-associated denture stomatitis.

The Role of Health Beliefs in the Regimen Adherence and Metabolic Control of Adolescents and Adults with Diabetes Mellitus.

ERIC Educational Resources Information Center

Brownlee-Duffeck, Martha; And Others

1987-01-01

Examined the role of health beliefs in diabetic regimen adherence and metabolic control. Health beliefs accounted for a statistically significant portion of the variance in both. For older patients perceived benefits of adhering to the diabetic regimen was most significant. For younger patients costs figured prominently in adherence and perceived…

Barriers to hydroxyurea adherence and health-related quality of life in adolescents and young adults with sickle cell disease.

PubMed

Badawy, Sherif M; Thompson, Alexis A; Penedo, Frank J; Lai, Jin-Shei; Rychlik, Karen; Liem, Robert I

2017-06-01

To identify barriers to hydroxyurea adherence (negative beliefs, access, and/or recall barriers), and their relationship to adherence rates and health-related quality of life (HRQOL) among adolescents and young adults (AYA) with sickle cell disease (SCD). A cross-sectional survey was administered to 34 AYAs (12-22 years old) in SCD clinics from January to December 2015. Study measures included Brief Medication Questionnaire, Modified Morisky Adherence Scale 8-items, visual analog scale, and Patient Reported Outcomes Measurement Information System. Participants (59% male; 91% Black) had a median age of 13.5 years (IQR 12-18). Participants reported negative beliefs (32%), recall barriers (44%), and access barriers (32%). Participants with recall barriers reported worse pain (P=.02), fatigue (P=.05), and depression (P=.05). The number of adherence barriers inversely correlated with adherence level using ©MMAS-8 (r s =-.38, P=.02) and VAS dose (r s =-.25, P=.14) as well as MCV (r s =-.45, P=.01) and HbF% (r s =-.36, P=.05), suggesting higher hydroxyurea adherence in patients with fewer barriers. Patients with fewer barriers to hydroxyurea adherence were more likely to have higher adherence rates and better HRQOL scores. Routine assessment of hydroxyurea adherence and its related barriers could provide actionable information to improve adherence rates, HRQOL, and other clinical outcomes. © 2017 The Authors. European Journal of Haematology Published by John Wiley & Sons Ltd.

Microparticles Engineered to Highly Express Peroxisome Proliferator-Activated Receptor-γ Decreased Inflammatory Mediator Production and Increased Adhesion of Recipient Monocytes

PubMed Central

Sahler, Julie; Woeller, Collynn F.; Phipps, Richard P.

2014-01-01

Circulating blood microparticles are submicron vesicles released primarily by megakaryocytes and platelets that act as transcellular communicators. Inflammatory conditions exhibit elevated blood microparticle numbers compared to healthy conditions. Direct functional consequences of microparticle composition, especially internal composition, on recipient cells are poorly understood. Our objective was to evaluate if microparticle composition could impact the function of recipient cells, particularly during inflammatory provocation. We therefore engineered the composition of megakaryocyte culture-derived microparticles to generate distinct microparticle populations that were given to human monocytes to assay for influences recipient cell function. Herein, we tested the responses of monocytes exposed to either control microparticles or microparticles that contain the anti-inflammatory transcription factor, peroxisome proliferator-activated receptor-γ (PPARγ). In order to normalize relative microparticle abundance from two microparticle populations, we implemented a novel approach that utilizes a Nanodrop Spectrophotometer to assay for microparticle density rather than concentration. We found that when given to peripheral blood mononuclear cells, microparticles were preferentially internalized by CD11b+ cells, and furthermore, microparticle composition had a profound functional impact on recipient monocytes. Specifically, microparticles containing PPARγ reduced activated monocyte production of the proinflammatory cytokines interleukin-8 and monocyte chemotactic protein-1 compared to activated monocytes exposed to control microparticles. Additionally, treatment with PPARγ microparticles greatly increased monocyte cell adherence. This change in morphology occurred simultaneously with increased production of the key extracellular matrix protein, fibronectin and increased expression of the fibronectin-binding integrin, ITGA5. PPARγ microparticles also changed monocyte mRNA levels of several genes including those under PPARγ control. Overall, the delivery of PPARγ from microparticles to human monocytes influenced gene expression, decreased inflammatory mediator production and increased monocyte adherence. These results support the concept that the composition of blood microparticles has a profound impact on the function of cells with which they interact, and likely plays a role in vascular inflammation. PMID:25426628

Microparticles engineered to highly express peroxisome proliferator-activated receptor-γ decreased inflammatory mediator production and increased adhesion of recipient monocytes.

PubMed

Sahler, Julie; Woeller, Collynn F; Phipps, Richard P

2014-01-01

Circulating blood microparticles are submicron vesicles released primarily by megakaryocytes and platelets that act as transcellular communicators. Inflammatory conditions exhibit elevated blood microparticle numbers compared to healthy conditions. Direct functional consequences of microparticle composition, especially internal composition, on recipient cells are poorly understood. Our objective was to evaluate if microparticle composition could impact the function of recipient cells, particularly during inflammatory provocation. We therefore engineered the composition of megakaryocyte culture-derived microparticles to generate distinct microparticle populations that were given to human monocytes to assay for influences recipient cell function. Herein, we tested the responses of monocytes exposed to either control microparticles or microparticles that contain the anti-inflammatory transcription factor, peroxisome proliferator-activated receptor-γ (PPARγ). In order to normalize relative microparticle abundance from two microparticle populations, we implemented a novel approach that utilizes a Nanodrop Spectrophotometer to assay for microparticle density rather than concentration. We found that when given to peripheral blood mononuclear cells, microparticles were preferentially internalized by CD11b+ cells, and furthermore, microparticle composition had a profound functional impact on recipient monocytes. Specifically, microparticles containing PPARγ reduced activated monocyte production of the proinflammatory cytokines interleukin-8 and monocyte chemotactic protein-1 compared to activated monocytes exposed to control microparticles. Additionally, treatment with PPARγ microparticles greatly increased monocyte cell adherence. This change in morphology occurred simultaneously with increased production of the key extracellular matrix protein, fibronectin and increased expression of the fibronectin-binding integrin, ITGA5. PPARγ microparticles also changed monocyte mRNA levels of several genes including those under PPARγ control. Overall, the delivery of PPARγ from microparticles to human monocytes influenced gene expression, decreased inflammatory mediator production and increased monocyte adherence. These results support the concept that the composition of blood microparticles has a profound impact on the function of cells with which they interact, and likely plays a role in vascular inflammation.

In vivo immunomodulatory, cumulative skin irritation, sensitization and effect of d-limonene on permeation of 6-mercaptopurine through transdermal drug delivery.

PubMed

Chandrashekar, N S; Hiremath, Shobha Rani Rajeev

2008-04-01

Using skin as a port for systemic drug administration, transdermal drug delivery has expanded greatly over the last two decades. Our aim was to formulate the single layer drug-in-adhesive transdermal patch for 6-mercaptopurine (6-MP). In vitro permeation study was carried out using modified Franz diffusion cell with and without of different concentration of d-limonene in human cadaver skin. In vivo immunomodulatory was carried out in mice, cumulative skin irritation, sensitization and patch adherence study was done in both mice and human subjects. 6-MP flux increased from 43+/-12.2 microg/cm2h (control) to 162.8+/-32.2 microg/cm2h (6% w/v d-limonene) data was significant (p<0.05), with decrease in the lag time to 35+/-9.3 min compared to control of 90 +/-15.3 min. In vivo immunomodulatory effect was shown in the Balb/c mice with 100 mumol/kg/body wt of animal for 5d (one dose/d) of d-limonene. WBC count of 13469 cells/mm peak was observed on 12th day, bone marrow cells of 26.3 x 10(6) cells/femur and alpha-esterase positive cells of 1259+/-328.4 cells/4000 bone marrow cells. Cumulative skin irritation, sensitisation and patch adherence in animals and human subjects showed no skin irritation and sensitization. Patch adhesion was greater than 90.0% respectively in both human subjects and mice. The percentage of human subjects with adhesive residue was significantly less with scores of zero. d-Limonene proved as good chemical enhancer by increasing in the skin permeability with shortened the lag time. It proved that therapeutic amount of 6-MP can be delivered through transdermal drug delivery.

Electrospun nanofibrous SF/P(LLA-CL) membrane: a potential substratum for endothelial keratoplasty.

PubMed

Chen, Junzhao; Yan, Chenxi; Zhu, Mengyu; Yao, Qinke; Shao, Chunyi; Lu, Wenjuan; Wang, Jing; Mo, Xiumei; Gu, Ping; Fu, Yao; Fan, Xianqun

2015-01-01

Cornea transplant technology has progressed markedly in recent decades, allowing surgeons to replace diseased corneal endothelium by a thin lamellar structure. A thin, transparent, biocompatible, tissue-engineered substratum with corneal endothelial cells for endothelial keratoplasty is currently of interest. Electrospinning a nanofibrous structure can simulate the extracellular matrix and have beneficial effects for cell culture. Silk fibroin (SF) has good biocompatibility but poor mechanical properties, while poly(L-lactic acid-co-ε-caprolactone) (P(LLA-CL)) has good mechanical properties but poor biocompatibility. Blending SF with P(LLA-CL) can maintain the advantages of both these materials and overcome their disadvantages. Blended electrospun nanofibrous membranes may be suitable for regeneration of the corneal endothelium. The aim of this study was to produce a tissue-engineered construct suitable for endothelial keratoplasty. Five scaffolds containing different SF:P(LLA-CL) blended ratios (100:0, 75:25, 50:50, 25:75, 0:100) were manufactured. A human corneal endothelial (B4G12) cell line was cultured on the membranes. Light transmission, speed of cell adherence, cell viability (live-dead test), cell proliferation (Ki-67, BrdU staining), and cell monolayer formation were detected on membranes with the different blended ratios, and expression of some functional genes was also detected by real-time polymerase chain reaction. Different blended ratios of scaffolds had different light transmittance properties. The 25:75 blended ratio membrane had the best transmittance among these scaffolds. All electrospun nanofibrous membranes showed improved speed of cell adherence when compared with the control group, especially when the P(LLA-CL) ratio increased. The 25:75 blended ratio membranes also had the highest cell proliferation. B4G12 cells could form a monolayer on all scaffolds, and most functional genes were also stably expressed on all scaffolds. Only two genes showed changes in expression. All blended ratios of SF:P(LLA-CL) scaffolds were evaluated and showed good biocompatibility for cell adherence and monolayer formation. Among them, the 25:75 blended ratio SF:P(LLA-CL) scaffold had the best transmittance and the highest cell proliferation. These attributes further the potential application of the SF:P(LLA-CL) scaffold for corneal endothelial transplantation.

Topical corticosteroids do not revert the activated phenotype of eosinophils in eosinophilic esophagitis but decrease surface levels of CD18 resulting in diminished adherence to ICAM-1, ICAM-2, and endothelial cells.

PubMed

Lingblom, Christine; Bergquist, Henrik; Johnsson, Marianne; Sundström, Patrik; Quiding-Järbrink, Marianne; Bove, Mogens; Wennerås, Christine

2014-12-01

Swallowed topical corticosteroids are the standard therapy for eosinophilic esophagitis (EoE) in adults. Eosinophils in the blood of untreated EoE patients have an activated phenotype. Our aim was to determine if corticosteroids restore the phenotype of eosinophils to a healthy phenotype and if certain cell-surface molecules on blood eosinophils correlate with eosinophilic infiltration of the esophagus. Levels of eight surface markers on eosinophils from treated and untreated EoE patients were determined by flow cytometry and analyzed using multivariate methods of pattern recognition. Corticosteroid-treated EoE patients' eosinophils had decreased levels of CD18 compared to both untreated patients and healthy controls, but maintained their activated phenotype. CD18 expression correlated positively with eosinophil numbers in the esophagus and promoted the adherence of eosinophils to ICAM-1, ICAM-2, and to endothelial cells. The diminished expression of CD18 may be one mechanism behind the reduced entry of eosinophils into the esophagus in corticosteroid-treated EoE patients.

Aspergillus Galactosaminogalactan Mediates Adherence to Host Constituents and Conceals Hyphal β-Glucan from the Immune System

PubMed Central

Liu, Hong; Lee, Mark J.; Snarr, Brendan D.; Chen, Dan; Xu, Wenjie; Kravtsov, Ilia; Hoareau, Christopher M. Q.; Vanier, Ghyslaine; Urb, Mirjam; Campoli, Paolo; Al Abdallah, Qusai; Lehoux, Melanie; Chabot, Josée C.; Ouimet, Marie-Claude; Baptista, Stefanie D.; Fritz, Jörg H.; Nierman, William C.; Latgé, Jean Paul; Mitchell, Aaron P.; Filler, Scott G.; Fontaine, Thierry; Sheppard, Donald C.

2013-01-01

Aspergillus fumigatus is the most common cause of invasive mold disease in humans. The mechanisms underlying the adherence of this mold to host cells and macromolecules have remained elusive. Using mutants with different adhesive properties and comparative transcriptomics, we discovered that the gene uge3, encoding a fungal epimerase, is required for adherence through mediating the synthesis of galactosaminogalactan. Galactosaminogalactan functions as the dominant adhesin of A. fumigatus and mediates adherence to plastic, fibronectin, and epithelial cells. In addition, galactosaminogalactan suppresses host inflammatory responses in vitro and in vivo, in part through masking cell wall β-glucans from recognition by dectin-1. Finally, galactosaminogalactan is essential for full virulence in two murine models of invasive aspergillosis. Collectively these data establish a role for galactosaminogalactan as a pivotal bifunctional virulence factor in the pathogenesis of invasive aspergillosis. PMID:23990787

The influence of personality traits and beliefs about medicines on adherence to asthma treatment.

PubMed

Emilsson, Maria; Berndtsson, Ina; Lötvall, Jan; Millqvist, Eva; Lundgren, Jesper; Johansson, Ake; Brink, Eva

2011-06-01

To explore the influence of personality traits and beliefs about medicines on adherence to treatment with asthma medication. Respondents were 35 asthmatic adults prescribed controller medication. They answered questionnaires about medication adherence, personality traits, and beliefs about medicines. In gender comparisons, the personality traits "Neuroticism" in men and "adherence to medication" were associated with lower adherent behaviour. Associations between personality traits and beliefs in the necessity of medication for controlling the illness were identified. Beliefs about the necessity of medication were positively associated with adherent behaviour in women. In the total sample, a positive "necessity-concern" differential predicted adherent behaviour. The results imply that personality and beliefs about medicines may influence how well adults with asthma adhere to treatment with asthma medication.

Optimization of Ex Vivo Murine Bone Marrow Derived Immature Dendritic Cells: A Comparative Analysis of Flask Culture Method and Mouse CD11c Positive Selection Kit Method

PubMed Central

Salwe, Sukeshani; Kothari, Sweta; Chowdhary, Abhay; Deshmukh, Ranjana A.

2018-01-01

12–14 days of culturing of bone marrow (BM) cells containing various growth factors is widely used method for generating dendritic cells (DCs) from suspended cell population. Here we compared flask culture method and commercially available CD11c Positive Selection kit method. Immature BMDCs' purity of adherent as well as suspended cell population was generated in the decreasing concentration of recombinant-murine granulocyte-macrophage colony-stimulating factor (rmGM-CSF) in nontreated tissue culture flasks. The expression of CD11c, MHCII, CD40, and CD86 was measured by flow cytometry. We found significant difference (P < 0.05) between the two methods in the adherent cells population but no significant difference was observed between the suspended cell populations with respect to CD11c+ count. However, CD11c+ was significantly higher in both adhered and suspended cell population by culture method but kit method gave more CD11c+ from suspended cells population only. On the other hand, using both methods, immature DC expressed moderate level of MHC class II molecules as well as low levels of CD40 and CD86. Our findings suggest that widely used culture method gives the best results in terms of yield, viability, and purity of BMDCs from both adherent and suspended cell population whereas kit method works well for suspended cell population. PMID:29682352

Optimization of Ex Vivo Murine Bone Marrow Derived Immature Dendritic Cells: A Comparative Analysis of Flask Culture Method and Mouse CD11c Positive Selection Kit Method.

PubMed

Gosavi, Rahul Ashok; Salwe, Sukeshani; Mukherjee, Sandeepan; Dahake, Ritwik; Kothari, Sweta; Patel, Vainav; Chowdhary, Abhay; Deshmukh, Ranjana A

2018-01-01

12-14 days of culturing of bone marrow (BM) cells containing various growth factors is widely used method for generating dendritic cells (DCs) from suspended cell population. Here we compared flask culture method and commercially available CD11c Positive Selection kit method. Immature BMDCs' purity of adherent as well as suspended cell population was generated in the decreasing concentration of recombinant-murine granulocyte-macrophage colony-stimulating factor (rmGM-CSF) in nontreated tissue culture flasks. The expression of CD11c, MHCII, CD40, and CD86 was measured by flow cytometry. We found significant difference ( P < 0.05) between the two methods in the adherent cells population but no significant difference was observed between the suspended cell populations with respect to CD11c+ count. However, CD11c+ was significantly higher in both adhered and suspended cell population by culture method but kit method gave more CD11c+ from suspended cells population only. On the other hand, using both methods, immature DC expressed moderate level of MHC class II molecules as well as low levels of CD40 and CD86. Our findings suggest that widely used culture method gives the best results in terms of yield, viability, and purity of BMDCs from both adherent and suspended cell population whereas kit method works well for suspended cell population.

[Inhibitive effect of LAK cells induced by dendritic cells on implanted lung cancer in nude mice].

PubMed

Gao, Qiu; Li, Jintian; Wang, Siyu; Chen, Shiping; Liu, Wei; Wu, Yilong

2004-10-20

To study the inhibitive effect of LAK cells induced by dendritic cells (DCs) on implanted lung adenocarcinoma in nude mice. The lung adenocarcinoma model was constructed in nude mice using the resected samples of lung cancer patient. The lung cancer cell lysate was obtained by free-zing and thrawing cycles. Peripheral blood mononuclear cells (PBMNC) were obtained from venous blood of the same patient, in which the adherent PBMNC fraction was cultured with DCGF, and the non-adherent PBMNC fraction was cultured with rhIL-2. DCs were pulsed with lung cancer cell lysates. And then mature DCs were incubated with LAK cells and the mixed cells were named DC-LAK cells. DC-LAK cells were injected into lung cancer-bearing nude mice to observe the inhibitive effect. The lung adenocarcinoma mo-del was successfully constructed. The average tumor weights of DC-LAK, LAK, DC and saline control groups were 0.47, 1.05, 1.30 and 1.58 g respectively, and the inhibitive rates of DC-LAK, LAK and DC were 70.3%, 33.5% and 17.9% respectively. The antitumor activity of DC-LAK cells was significantly stronger than that of LAK cells (P < 0.05). The results of in vivo experiment show that the antitumor activity of DC-LAK cells is stronger than that of LAK cells, so DC-LAK cells treatment may be a more efficient approach of lung cancer biological therapy. This experiment may provide a foundation for clinical application of DC vaccine.

Financial incentives to improve adherence to anti-psychotic maintenance medication in non-adherent patients - a cluster randomised controlled trial (FIAT).

PubMed

Priebe, Stefan; Burton, Alexandra; Ashby, Deborah; Ashcroft, Richard; Burns, Tom; David, Anthony; Eldridge, Sandra; Firn, Mike; Knapp, Martin; McCabe, Rose

2009-09-28

Various interventions have been tested to achieve adherence to anti-psychotic maintenance medication in non-adherent patients with psychotic disorders, and there is no consistent evidence for the effectiveness of any established intervention. The effectiveness of financial incentives in improving adherence to a range of treatments has been demonstrated; no randomised controlled trial however has tested the use of financial incentives to achieve medication adherence for patients with psychotic disorders living in the community. In a cluster randomised controlled trial, 34 mental health teams caring for difficult to engage patients in the community will be randomly allocated to either the intervention group, where patients will be offered a financial incentive for each anti-psychotic depot medication they receive over a 12 month period, or the control group, where all patients will receive treatment as usual. We will recruit 136 patients with psychotic disorders who use these services and who have problems adhering to antipsychotic depot medication, although all conventional methods to achieve adherence have been tried. The primary outcome will be adherence levels, and secondary outcomes are global clinical improvement, number of voluntary and involuntary hospital admissions, number of attempted and completed suicides, incidents of physical violence, number of police arrests, number of days spent in work/training/education, subjective quality of life and satisfaction with medication. We will also establish the cost effectiveness of offering financial incentives. The study aims to provide new evidence on the effectiveness and cost effectiveness of offering financial incentives to patients with psychotic disorders to adhere to antipsychotic maintenance medication. If financial incentives improve adherence and lead to better health and social outcomes, they may be recommended as one option to improve the treatment of non-adherent patients with psychotic disorders. Current controlled trials ISRCTN77769281.

Adherence Reduction of Campylobacter jejuni and Campylobacter coli Strains to HEp-2 Cells by Mannan Oligosaccharides and a High-Molecular-Weight Component of Cranberry Extract.

PubMed

Ramirez-Hernandez, Alejandra; Rupnow, John; Hutkins, Robert W

2015-08-01

Campylobacter infections are a leading cause of human bacterial gastroenteritis in the United States and are a major cause of diarrheal disease throughout the world. Colonization and subsequent infection and invasion of Campylobacter require that the bacteria adhere to the surface of host cells. Agents that inhibit adherence could be used prophylactically to reduce Campylobacter carriage and infection. Mannan oligosaccharides (MOS) have been used as a feed supplement in livestock animals to improve performance and to replace growth-promoting antibiotics. However, MOS and other nondigestible oligosaccharides may also prevent pathogen colonization by inhibiting adherence in the gastrointestinal tract. In addition, plant extracts, including those derived from cranberries, have been shown to have antiadherence activity against pathogens. The goal of this study was to assess the ability of MOS and cranberry fractions to serve as antiadherence agents against strains of Campylobacter jejuni and Campylobacter coli. Adherence experiments were performed using HEp-2 cells. Significant reductions in adherence of C. jejuni 29438, C. jejuni 700819, C. jejuni 3329, and C. coli 43485 were observed in the presence of MOS (up to 40 mg/ml) and with a high-molecular-weight fraction of cranberry extract (up to 3 mg/ml). However, none of the tested materials reduced adherence of C. coli BAA-1061. No additive effect in adherence inhibition was observed for an MOS-cranberry blend. These results suggest that both components, MOS and cranberry, could be used to reduce Campylobacter colonization and carriage in livestock animals and potentially limit human exposure to this pathogen.

Apa is a trimeric autotransporter adhesin of Actinobacillus pleuropneumoniae responsible for autoagglutination and host cell adherence.

PubMed

Xiao, Longwen; Zhou, Liang; Sun, Changjiang; Feng, Xin; Du, ChongTao; Gao, Yu; Ji, Qun; Yang, Shuxin; Wang, Yu; Han, Wenyu; Langford, P R; Lei, Liancheng

2012-10-01

Actinobacillus pleuropneumoniae is the causative agent of porcine pleuropneumonia, and adherence to host cells is a key step in the pathogenic process. Although trimeric autotransporter adhesins (TAAs) were identified in many pathogenic bacteria in recent years, none in A. pleuropneumoniae have been characterized. In this study, we identified a TAA from A. pleuropneumoniae, Apa, and characterized the contribution of its amino acid residues to the adhesion process. Sequence analysis of the C-terminal amino acid residues of Apa revealed the presence of a putative translocator domain and six conserved HsfBD1-like or HsfBD2-like binding domains. Western blot analysis revealed that the 126 C-terminal amino acids of Apa could form trimeric molecules. By confocal laser scanning microscopy, one of these six domains (ApaBD3) was determined to mediate adherence to epithelial cells. Adherence assays and adherence inhibition assays using a recombinant E. coli- ApaBD3 strain which expressed ApaBD3 on the surface of E. coli confirmed that this domain was responsible for the adhesion activity. Moreover, cellular enzyme-linked immunosorbent assays demonstrated that ApaBD3 mediated high-level adherence to epithelial cell lines. Intriguingly, autoagglutination was observed with the E. coli- ApaBD3 strain, and this phenomenon was dependent upon the association of the expressed ApaBD3 with the C-terminal translocator domain. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effect of self-efficacy and social support on adherence to antihypertensive drugs.

PubMed

Criswell, Thomas J; Weber, Cynthia A; Xu, Yinghui; Carter, Barry L

2010-05-01

To determine the relationship between poor adherence and self-efficacy or social support after a pharmacist intervention. Post-hoc analysis of data from two randomized controlled trials of physician-pharmacist collaborative interventions (6 and 9 mo, respectively) to improve blood pressure control. Eleven university-affiliated primary care clinics. Five hundred eighty-four patients (aged 21-85 yrs) with uncontrolled primary hypertension; 296 were in the intervention group and 288 were in the control group. Pharmacists provided intensified hypertension management and drug adherence counseling to patients in the intervention group. Social support and self-efficacy questionnaires were administered at baseline and end-of-study visits. Patient adherence was monitored by using the Morisky self-reported adherence questionnaire. Self-reported adherence scores improved significantly in the control group (p=0.0053) but not in the intervention group; however, adherence at baseline in both groups was high. There were small, but significant, improvements in self-efficacy (p<0.04) and social support (p<0.05) scores in the intervention group but not the control group at the end of the study. Social support and, to a lesser extent, self-efficacy improved as a function of duration of study participation (9-mo vs 6-mo intervention), regardless of whether the patient received the intervention. Blood pressure control in both groups improved significantly at the end of the study; however, mean blood pressure was significantly lower in the intervention group (129.7/76.6 mm Hg) compared with the control group (140.8/78.9 mm Hg; p<0.0001 for systolic, p=0.032 for diastolic). Social support and self-efficacy improved significantly in the intervention group at the end of the pharmacist intervention. Drug adherence was correlated with self-efficacy even though drug adherence did not improve significantly in the intervention group. The fact that social support and self-efficacy improved as a function of duration of study participation suggests that participation in a research study may have had a positive influence on these measures. Even though the changes in social support, self-efficacy, and drug adherence were modest, there was significantly better blood pressure control in the intervention group compared with the control group. These findings indicate that changes in drug adherence, self-efficacy, or social support probably played a minor role in the blood pressure outcomes in these studies.

Curli temper adherence of Escherichia coli O157:H7 to squamous epithelial cells from the bovine recto-anal junction in a strain-dependent manner

USDA-ARS?s Scientific Manuscript database

Our recent studies have shown that Intimin and the Locus of Enterocyte Effacement-encoded proteins do not play a role in Escherichia coli O157 (O157) adherence to the bovine recto-anal junction squamous epithelial cells (RSE) cells. Hence, to define factors that play a contributory role, we investi...

Interaction of Mycobacterium tuberculosis with human respiratory mucosa.

PubMed

Middleton, A M; Chadwick, M V; Nicholson, A G; Dewar, A; Groger, R K; Brown, E J; Ratliff, T L; Wilson, R

2002-01-01

Endobronchial infection is associated with pulmonary tuberculosis in the majority of cases. We have investigated the adherence of Mycobacterium tuberculosis to the human respiratory mucosa. Organ cultures constructed with human tissue were infected with M. tuberculosis in the presence or absence of mycobacterial fibronectin attachment cell surface proteins and examined by scanning electron microscopy. M. tuberculosis adhered mainly to extracellular matrix (ECM) in areas of mucosal damage, but not to ciliated mucosa, intact extruded cells, basement membrane or collagen fibres. Bacteria also adhered to fibrous but not globular mucus and occasionally to healthy unciliated mucosa, open tight junctions and to extruded cells that had degenerated, exposing their contents. There was a significant reduction (p<0.05) in the number of bacteria adhering to ECM after pre-incubation of bacteria with fibronectin and after pre-incubation of the tissue with M. avium fibronectin attachment protein (FAP) and M. bovis antigen 85B protein, in a concentration dependent manner. The combined effect of FAP and antigen 85B protein was significantly greater than either protein alone. Bacterial adherence to fibrous mucus was not influenced by fibronectin. We conclude that M. tuberculosis adheres to ECM in areas of mucosal damage at least in part via FAP and antigen 85B protein.

Peripheral Blood Mononuclear Cells Enhance Cartilage Repair in in vivo Osteochondral Defect Model.

PubMed

Hopper, Niina; Wardale, John; Brooks, Roger; Power, Jonathan; Rushton, Neil; Henson, Frances

2015-01-01

This study characterized peripheral blood mononuclear cells (PBMC) in terms of their potential in cartilage repair and investigated their ability to improve the healing in a pre-clinical large animal model. Human PBMCs were isolated with gradient centrifugation and adherent PBMC's were evaluated for their ability to differentiate into adipogenic, chondrogenic and osteogenic lineages and also for their expression of musculoskeletal genes. The phenotype of the PBMCs was evaluated using Stro-1, CD34, CD44, CD45, CD90, CD106, CD105, CD146 and CD166 cell surface markers. Osteochondral defects were created in the medial femoral condyle (MFC) of 24 Welsh mountain sheep and evaluated at a six month time point. Four cell treatment groups were evaluated in combination with collagen-GAG-scaffold: (1) MSC alone; (2) MSCs and PBMCs at a ratio of 20:1; (3) MSCs and PBMC at a ratio of 2:1 and (4) PBMCs alone. Samples from the surgical site were evaluated for mechanical properties, ICRS score and histological repair. Fresh PBMC samples were 90% positive for hematopoietic cell surface markers and negative for the MSC antibody panel (<1%, p = 0.006). However, the adherent PBMC population expressed mesenchymal stem cell markers in hypoxic culture and lacked CD34/45 positive cells (<0.2%). This finding demonstrated that the adherent cells had acquired an MSC-like phenotype and transformed in hypoxia from their original hematopoietic lineage. Four key genes in muskuloskeletal biology were significantly upregulated in adherent PBMCs by hypoxia: BMP2 4.2-fold (p = 0.0007), BMP6 10.7-fold (p = 0.0004), GDF5 2.0-fold (p = 0.002) and COL1 5.0-fold (p = 0.046). The monolayer multilineage analysis confirmed the trilineage mesenchymal potential of the adherent PBMCs. PBMC cell therapy was equally good as bone marrow MSC therapy for defects in the ovine large animal model. Our results show that PBMCs support cartilage healing and oxygen tension of the environment was found to have a key effect on the derivation of a novel adherent cell population with an MSC-like phenotype. This study presents a novel and easily attainable point-of-care cell therapy with PBMCs to treat osteochondral defects in the knee avoiding any cell manipulations outside the surgical room.

Harnessing nanotopography and integrin-matrix interactions to influence stem cell fate

NASA Astrophysics Data System (ADS)

Dalby, Matthew J.; Gadegaard, Nikolaj; Oreffo, Richard O. C.

2014-06-01

Stem cells respond to nanoscale surface features, with changes in cell growth and differentiation mediated by alterations in cell adhesion. The interaction of nanotopographical features with integrin receptors in the cells' focal adhesions alters how the cells adhere to materials surfaces, and defines cell fate through changes in both cell biochemistry and cell morphology. In this Review, we discuss how cell adhesions interact with nanotopography, and we provide insight as to how materials scientists can exploit these interactions to direct stem cell fate and to understand how the behaviour of stem cells in their niche can be controlled. We expect knowledge gained from the study of cell-nanotopography interactions to accelerate the development of next-generation stem cell culture materials and implant interfaces, and to fuel discovery of stem cell therapeutics to support regenerative therapies.

The role played by the group A streptococcal negative regulator Nra on bacterial interactions with epithelial cells.

PubMed

Molinari, G; Rohde, M; Talay, S R; Chhatwal, G S; Beckert, S; Podbielski, A

2001-04-01

Group A streptococci (GAS) specifically attach to and internalize into human epithelial host cells. In some GAS isolates, fibronectin-binding proteins were identified as being responsible for these virulence traits. In the present study, the previously identified global negative regulator Nra was shown to control the binding of soluble fibronectin probably via regulation of protein F2 and/or SfbII expression in the serotype M49 strain 591. According to results from a conventional invasion assay based on the recovery of viable intracellular bacteria, the increased fibronectin binding did not affect bacterial adherence to HEp-2 epithelial cells, but was associated with a reduction in the internalization rates. However, when examined by confocal and electron microscopy techniques, the nra-mutant bacteria were shown to exhibit higher adherence and internalization rates than the corresponding wild type. The mutant bacteria escaped from the phagocytic vacuoles much faster, promoting consistent morphological changes which resulted in severe host cell damage. The apoptotic and lytic processes observed in nra-mutant infected host cells were correlated with an increased expression of the genes encoding superantigen SpeA, the cysteine protease SpeB, and streptolysin S in the nra-mutant bacteria. Adherence and internalization rates of a nra/speB-double mutant at wild-type levels indicated that the altered speB expression in the nra mutant contributed to the observed changes in both processes. The Nra-dependent effects on bacterial virulence were confined to infections carried out with stationary growth phase bacteria. In conclusion, the obtained results demonstrated that the global GAS regulator Nra modulates virulence genes, which are involved in host cell damage. Thus, by helping to achieve a critical balance of virulence factor expression that avoids the injury of target cells, Nra may facilitate GAS persistence in a safe intracellular niche.

The effect of partially stabilized zirconia on the biological properties of HA/HDPE composites in vitro.

PubMed

Sadi, A Yari; Shokrgozar, M A; Homaeigohar, S Sh; Hosseinalipour, M; Khavandi, A; Javadpour, J

2006-05-01

The effect of partially stabilized zirconia (PSZ) on the biological properties of the hyroxyapatite - high density polyethylene (HA/HDPE) composites was studied by investigating the simultaneous effect of hydroxyapatite and PSZ volume fractions on the in vitro response of human osteoblast cells. The biocompatibility of composite samples with different volume fraction of HA and PSZ powders was assessed by proliferation, alkaline phosphatase (ALP) and cell attachment assays on the osteoblast cell line (G-292) in different time periods. The effect of composites on the behavior of G-292 cells was compared with those of HDPE and TPS (Tissue Culture Poly Styrene as negative control) samples. Results showed a higher proliferation rate of G-292 cells in the presence of composite samples as compared to the HDPE sample after 7 and 14 days of incubation period. ALP production rate in all composite samples was higher than HDPE and TPS samples. The number of adhered cells on the composite samples was higher than the number adhered on the HDPE and TPS samples after the above mentioned incubation periods. These findings indicates that the addition of PSZ does not have any adverse affect on the biocompatibility of HA/HDPE composites. In fact in some experiments PSZ added HA/HDPE composites performed better in proliferation, differentiation and attachment of osteoblastic cells.

A contractile and counterbalancing adhesion system controls the 3D shape of crawling cells.

PubMed

Burnette, Dylan T; Shao, Lin; Ott, Carolyn; Pasapera, Ana M; Fischer, Robert S; Baird, Michelle A; Der Loughian, Christelle; Delanoe-Ayari, Helene; Paszek, Matthew J; Davidson, Michael W; Betzig, Eric; Lippincott-Schwartz, Jennifer

2014-04-14

How adherent and contractile systems coordinate to promote cell shape changes is unclear. Here, we define a counterbalanced adhesion/contraction model for cell shape control. Live-cell microscopy data showed a crucial role for a contractile meshwork at the top of the cell, which is composed of actin arcs and myosin IIA filaments. The contractile actin meshwork is organized like muscle sarcomeres, with repeating myosin II filaments separated by the actin bundling protein α-actinin, and is mechanically coupled to noncontractile dorsal actin fibers that run from top to bottom in the cell. When the meshwork contracts, it pulls the dorsal fibers away from the substrate. This pulling force is counterbalanced by the dorsal fibers' attachment to focal adhesions, causing the fibers to bend downward and flattening the cell. This model is likely to be relevant for understanding how cells configure themselves to complex surfaces, protrude into tight spaces, and generate three-dimensional forces on the growth substrate under both healthy and diseased conditions.

A contractile and counterbalancing adhesion system controls the 3D shape of crawling cells

PubMed Central

Burnette, Dylan T.; Shao, Lin; Ott, Carolyn; Pasapera, Ana M.; Fischer, Robert S.; Baird, Michelle A.; Der Loughian, Christelle; Delanoe-Ayari, Helene; Paszek, Matthew J.; Davidson, Michael W.; Betzig, Eric

2014-01-01

How adherent and contractile systems coordinate to promote cell shape changes is unclear. Here, we define a counterbalanced adhesion/contraction model for cell shape control. Live-cell microscopy data showed a crucial role for a contractile meshwork at the top of the cell, which is composed of actin arcs and myosin IIA filaments. The contractile actin meshwork is organized like muscle sarcomeres, with repeating myosin II filaments separated by the actin bundling protein α-actinin, and is mechanically coupled to noncontractile dorsal actin fibers that run from top to bottom in the cell. When the meshwork contracts, it pulls the dorsal fibers away from the substrate. This pulling force is counterbalanced by the dorsal fibers’ attachment to focal adhesions, causing the fibers to bend downward and flattening the cell. This model is likely to be relevant for understanding how cells configure themselves to complex surfaces, protrude into tight spaces, and generate three-dimensional forces on the growth substrate under both healthy and diseased conditions. PMID:24711500

[In Vitro and In Vivo Biocompatibility of a Novel, 3-Dimensional Cellulose Matrix Structure].

PubMed

Dunda, S E; Ranker, M; Pallua, N; Machens, H-G; Ravichandran, A; Schantz, J-T

2015-12-01

Biological and physical characteristics of matrices are one essential factor in creating bioartificial tissue. In this study, a new 3-dimensional cellulose matrix (Xellulin(®)) was tested in terms of biocompatibility and applicability for tissue engineering in vitro and in vivo. The tested matrix Xellulin(®) is a natural hydrological gel-matrix containing bacterial cellulose and water. To evaluate the cell biocompatibilty, cell adherence and proliferation characteristics in vitro, the matrix was cultured with human fibroblasts. Further in vivo studies were carried out by transplanting preadipocytes of 4- to 6-week-old Wistar rats with 3 different conditions: a) Xellulin(®) including 500 000 preadipocytes subcutaneous, b) Xellulin(®) including 500 000 preadipocytes within an in vivo bioreactor chamber, c) Xellulin(®) without cells subcutaneous as control. After explantation on day 14 histomorphological and immunohistochemical evaluations were performed. In vitro study revealed an excellent biocompatibility with good cell adherence of the fibroblasts on the matrix and evidence of cell proliferation and creation of a 3-dimensional cell network. In vivo neocapillarisation could be shown in all groups with evidence of erythrocytes (H/E staining) and endothelial vascular cells (RECA-1-staining). A significantly higher vascular density was shown in vascularised bioreactor group (18.4 vessels/100 000 µm(2) (group b) vs. 8.1 (group a), p<0.05). Cell density was the highest in the vascularised group, but without significant values. No immunogenic reaction to the matrix was noticed. The promising in vitro results concerning cell adherence and proliferation on the tested matrix could be confirmed in vivo with an evidence of 3-dimensional neocapillarisation. Cell survival was higher in the vascularised group, but without significance. Long-term tests (28-42 days) need to be carried out to evaluate long-term cell survival and the matrix stability. Furthermore, studies concerning the implementation of the matrix within anatomic structures as well as long-term biocompatibility are needed. © Georg Thieme Verlag KG Stuttgart · New York.

The effect of Taurolidine on adherent and floating subpopulations of melanoma cells.

PubMed

Shrayer, D P; Lukoff, H; King, T; Calabresi, P

2003-04-01

The annual incidence of malignant melanoma is estimated at 10-12 per 100000 inhabitants in countries of Central Europe and the US, with more recent estimates showing a dramatic upward trend. Taurolidine (Carter/Wallace, Cranberry, NJ) is a novel, potentially effective, antitumor chemotherapeutic agent. We hypothesized that Taurolidine could inhibit the growth, induce apoptosis, affect the cell cycle and change morphology of melanoma cells. We expected this process to be different in adherent and floating subpopulations that may be reflective of solid tumors and their metastases. Analysis of MNT-1 human and B16F10 murine melanoma cells showed that at 72 h the IC(50) of Taurolidine was 25.4+/-3.3 microM for MNT-1 human melanoma cells and 30.9+/-3.6 microM for B16F10 murine melanoma cells. Taurolidine induced DNA fragmentation of melanoma cells in a dose-dependent manner. Taurolidine (75 and 100 microM) induced 52-97% Annexin-V binding (apoptosis), respectively. Evaluation of cell cycle after 72 h exposure to Taurolidine (0-100 microM) revealed that the percentage of melanoma cells in S phase increased from 27 to 40% in the adherent subpopulation and from 33 to 49% in the floating subpopulation. Phase contrast microscopy revealed a marked swelling of melanoma cells and decreasing cell numbers in adherent subpopulation starting at 24 h with 25 microM Taurolidine. Shrinkage of cells dominated at 75-100 microM Taurolidine. Using Cytospin assay in the floating population, we observed swelling of melanoma cells induced by 25-100 micro Taurolidine and appearance of giant (multinuclear) forms resulting from exposure to 75-100 micro Taurolidine. Some floating cells with normal morphology were observed with low concentrations of Taurolidine (0-25 microM). These data show that effects of Taurolidine may be different in adherent and floating subpopulations of melanoma cells. More importantly, floating subpopulations that may contain some viable melanoma cells, may be reflective of potential metastasis after treatment of solid tumors in vivo.

Feasibility and Acceptability of Internet-delivered Cognitive Behavioral Therapy for Chronic Pain in Adolescents With Sickle Cell Disease and Their Parents.

PubMed

Palermo, Tonya M; Dudeney, Joanne; Santanelli, James P; Carletti, Alexie; Zempsky, William T

2018-03-01

Pain is a clinical hallmark of sickle cell disease (SCD), and is rarely optimally managed. Cognitive-behavioral therapy (CBT) for pain has been effectively delivered through the Internet in other pediatric populations. We tested feasibility and acceptability of an Internet-delivered CBT intervention in 25 adolescents with SCD (64% female, mean age=14.8 y) and their parents randomized to Internet CBT (n=15) or Internet Pain Education (n=10). Participants completed pretreatment/posttreatment measures. Eight dyads completed semistructured interviews to evaluate treatment acceptability. Feasibility indicators included recruitment and participation rates, engagement and adherence to intervention, and completion of outcome measures. In total, 87 referrals were received from 9 study sites; our recruitment rate was 60% from those families approached for screening. Among participants, high levels of initial intervention engagement (>90%), and adherence (>70%) were demonstrated. Most participants completed posttreatment outcome and diary measures (>75%). Retention at posttreatment was 80%. High treatment acceptability was reported in interviews. Our findings suggest that Internet-delivered CBT for SCD pain is feasible and acceptable to adolescents with SCD and their parents. Engagement and adherence were good. Next steps are to modify recruitment plans to enhance enrollment and determine efficacy of Internet CBT for SCD pain in a large multisite randomized controlled trial.

Factors associated with therapeutic success in HIV-positive individuals in southern Brazil.

PubMed

Silveira, M P T; Maurer, P; Guttier, M C; Moreira, L B

2015-04-01

Therapeutic success is characterized by undetectable viral load, immune reconstitution confirmed by CD4+ T-cell count and no clinical manifestations of disease. High treatment adherence is a major determinant of therapeutic success that needs prevention of viral replication, allowing immune reconstitution. Adherence to treatment <95% has been associated with both immune and viral failure. The objective of this study was to evaluate factors associated with therapeutic success in adult patients on highly active antiretroviral therapy (HAART) in a specialized centre for HIV-AIDS in southern Brazil, being defined therapeutic success as achieving and maintaining undetectable viral load, stable immune status (CD4+ T lymphocyte count ≥200 cells/mm(3) ) and adherence to HAART ≥ 95%. We conducted a historical cohort study nested in the PC-HIV randomized clinical trial of PC-HIV. We included adults who were on HAART at Pelotas HIV/AIDS Assistance Service between June 2006 and July 2007 and for whom information on treatment adherence, viral load and CD4+ cell count was available. Pregnant women were excluded. We obtained clinical data from medical records and socio-demographic information in an interview. Therapeutic success was defined as achieving and maintaining undetectable viral load, stable immune status (CD4+ T lymphocyte count ≥200 cells/mm(3) ) and adherence to HAART ≥95%. We included 136 patients (60% male) in the cohort study. Mean age was 40 ± 10 years, and median treatment duration was 59 months (IQR 25-93). Family income varied from 0 to 8 times the minimum wage (IQR 1·0-2·3). Therapeutic success was achieved by 90% (122 patients), and it was associated with previously undetectable viral load (PR = 1·30; 95% CI = 1·13-1·49) and treatment adherence prior to study entry (PR = 1·34; 95% CI = 1·07-1·69), independently of sex, age and previous immune status. When undetectable viral load, CD4+ cell count ≥200 cells/mm(3) and treatment adherence above 95% are included in the definition of therapeutic success, the rate was elevated (90%) and the factors associated were previous history of adherence to HAART and previous undetectable viral load. © 2014 John Wiley & Sons Ltd.

Ultrasonic Analysis of Peptide- and Antibody-Targeted Microbubble Contrast Agents for Molecular Imaging of αvβ3-Expressing Cells

PubMed Central

Dayton, Paul A.; Pearson, David; Clark, Jarrod; Simon, Scott; Schumann, Patricia A.; Zutshi, Reena; Matsunaga, Terry O.; Ferrara, Katherine W.

2008-01-01

The goal of targeted ultrasound contrast agents is to significantly and selectively enhance the detection of a targeted vascular site. In this manuscript, three distinct contrast agents targeted to the αvβ3 integrin are examined. The αvβ3 integrin has been shown to be highly expressed on metastatic tumors and endothelial cells during neovascularization, and its expression has been shown to correlate with tumor grade. Specific adhesion of these contrast agents to αvβ3-expressing cell monolayers is demonstrated in vitro, and compared with that of nontargeted agents. Acoustic studies illustrate a backscatter amplitude increase from monolayers exposed to the targeted contrast agents of up to 13-fold (22 dB) relative to enhancement due to control bubbles. A linear dependence between the echo amplitude and bubble concentration was observed for bound agents. The decorrelation of the echo from adherent targeted agents is observed over successive pulses as a function of acoustic pressure and bubble density. Frequency–domain analysis demonstrates that adherent targeted bubbles exhibit high-amplitude narrowband echo components, in contrast to the primarily wideband response from free microbubbles. Results suggest that adherent targeted contrast agents are differentiable from free-floating microbubbles, that targeted contrast agents provide higher sensitivity in the detection of angiogenesis, and that conventional ultrasound imaging techniques such as signal subtraction or decorrelation detection can be used to detect integrin-expressing vasculature with sufficient signal-to-noise. PMID:15296677

Loss of an actin crosslinker uncouples cell spreading from cell stiffening on gels with a gradient of stiffness

NASA Astrophysics Data System (ADS)

Wen, Qi; Byfield, Fitzroy J.; Nordstrom, Kerstin; Arratia, Paulo E.; Miller, R. Tyler; Janmey, Paul A.

2009-03-01

We use microfluidics techniques to produce gels with a gradient of stiffness to show the essential function of the actin crosslinker filamin A in cell responses to mechanical stimuli. M2 melanoma cells null for filamin A do not alter their adherent area in response to increased substrate stiffness when they link to the substrate only through collagen receptors, but change adherent area normally when bound through fibronectin receptors. In contrast, filamin A-replete A7 cells change adherent area on both substrates and respond more strongly to collagen 1-coated gels than to fibronectin-coated gels. A7 cells alter their stiffness, as measured by atomic force microscopy, to match the elastic modulus of the substrate immediately adjacent to them on the gradient. M2 cells, in contrast, maintain a constant stiffness on all substrates that is as low as that of A7 cells on the softest gels achievable (1000 Pa). By contrasting the responses of these cell types to different adhesive substrates, cell spreading can be dissociated from stiffening.

Asthma medication adherence: the role of God and other health locus of control factors.

PubMed

Ahmedani, Brian K; Peterson, Edward L; Wells, Karen E; Rand, Cynthia S; Williams, L Keoki

2013-02-01

Medication adherence is an important determinant of disease outcomes, yet medication use on average tends to be low among patients with chronic conditions, including asthma. Although several predictors of non-adherence have been assessed, more research is needed on patients' beliefs about God and how these relate to medication use. To examine the relationship between perceptions about "God's" role in health and other locus of control factors with inhaled corticosteroid (ICS) adherence among asthma patients. Participants were from a clinical trial to improve ICS adherence and were 5-56 years old, had a diagnosis of asthma, and were receiving ICS medication. Baseline adherence was estimated from electronic prescription and pharmacy fill records. Patients were considered to be adherent if ICS use was ≥80% of prescribed. A baseline survey with the Multidimensional Health Locus of Control scale was used to assess five sources (God, doctors, other people, chance, and internal). Medication adherence was low (36%). Patients' who had a stronger belief that God determined asthma control were less likely to be adherent (odds ratio [OR] 0.82, 95% confidence interval [CI] 0.70-0.96). This relationship was stronger among African American (OR 0.68, 95% CI0.47-0.99) compared to white patients (OR 0.89, 95% CI 0.75-1.04), and among adults (OR 0.81, 95% CI 0.69-0.96) compared to children (OR 0.84, 95% CI 0.58-1.22). Patients' belief in God's control of health appears to be a factor in asthma controller use, and therefore should be considered in physician-patient discussions concerning course of treatment. ClinicalTrials.gov: NCT00459368. Copyright © 2013 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Impact of adherence to antidepressants on healthcare outcomes and costs among patients with type 2 diabetes and comorbid major depressive disorder.

PubMed

Vega, Charles; Becker, Russell V; Mucha, Lisa; Lorenz, Betty H; Eaddy, Michael T; Ogbonnaya, Augustina O

2017-10-01

To evaluate the association between adherence to antidepressants and an effect on clinical outcomes and healthcare costs in patients with major depressive disorder (MDD) and comorbid type 2 diabetes (T2D). This retrospective study used MarketScan claims data from January 2012 to March 2014. Study entry was the first claim for an antidepressant and a diagnosis code for MDD and T2D in the prior 6 months. Adherence and persistence with antidepressant therapy in the first 180 days were defined as medication possession ratio (MPR) ≥ 80% and length of therapy (LOT), with no treatment gap of >15 days, respectively. T2D control (HbA1c <7%), oral diabetes medication adherence, and healthcare costs were measured in the 12 month post-index period. The impact of antidepressant adherence and persistence on outcomes was assessed using multivariable analyses. Among the 1361 patients included, the mean age was 59 years and 55% were women. About one-third of the patients were adherent (35.9%, mean MPR = 40%), persistent (32.0%, average LOT = 100 days), and adherent/persistent (31.2%) on antidepressants. Being adherent, persistent, or adherent/persistent to antidepressants was associated with a two-fold improvement in adherence to oral diabetes medications. Of those with HbA1c data (n = 121), adherence or adherence/persistence to antidepressants was associated with patients being five times more likely to have T2D control (odds ratio [OR]: 4.95; 95% confidence interval [CI]: 1.39, 17.59, p = .0134). Comparison between antidepressant-persistent and non-persistent patients was not significant. Mean difference in adjusted all-cause annual costs showed lower costs among antidepressant-adherent and adherent/persistent patients (adherent: -$350, 95% CI: -$462, -$247; adherent/persistent: -$1165; 95% CI: -$1280, -$1060). Patients with better antidepressant adherence and adherence/persistence demonstrated better HbA1c control, with lower all-cause total and medical costs. Adherence, persistence, or adherence/persistence to antidepressants was associated with improved adherence to oral diabetes medications.

Exploratory Analysis of Exercise Adherence Patterns with Sedentary Pregnant Women

PubMed Central

Yeo, SeonAe; Cisewski, Jessi; Lock, Eric F.; Marron, J. S.

2010-01-01

Background It is not well understood how sedentary women who wish to engage in regular exercise adhere to interventions during pregnancy and what factors may influence adherence over time. Objective To examine longitudinal patterns of pregnant women’s adherence to exercise. Methods Exploratory secondary data analyses were carried out with 124 previously sedentary pregnant women (ages 31 ± 5 years; 85% non-Hispanic White) from a randomized controlled trial. Daily exercise logs (n = 92) from 18 through 35 weeks of gestation were explored using linear regression, functional data, and principal component analyses. Results Adherence decreased as gestation week increased (p < .001); the top adherers maintained levels of adherence, and the bottom adherers decreased levels of adherence; and adherence pattern was influenced by types of exercise throughout the study period. Discussion Exercise behavior patterns were explored in a randomized controlled trial study, using chronometric data on exercise attendance. A new analytic approach revealed that sedentary pregnant women may adopt exercise habits differently from other populations. PMID:20585224

Adherence to Tuberculosis Treatment among Migrant Pulmonary Tuberculosis Patients in Shandong, China: A Quantitative Survey Study

PubMed Central

Zhou, Chengchao; Chu, Jie; Liu, Jinan; Gai Tobe, Ruoyan; Gen, Hong; Wang, Xingzhou; Zheng, Wengui; Xu, Lingzhong

2012-01-01

Adherence to TB treatment is the most important requirement for efficient TB control. Migrant TB patients’ “migratory” nature affects the adherence negatively, which presents an important barrier for National TB Control Program in China. Therefore, TB control among migrants is of high importance.The aim of this study is to describe adherence to TB treatment among migrant TB patients and to identify factors associated with adherence. A total of 12 counties/districts of Shandong Province, China were selected as study sites. 314 confirmed smear positive TB patients were enrolled between August 2nd 2008 and October 17th 2008, 16% of whom were non-adherent to TB therapy. Risk factors for non-adherence were: the divorced or bereft of spouse, patients not receiving TB-related health education before chemotherapy, weak incentives for treatment adherence, and self supervision on treatment. Based on the risk factors identified, measures are recommended such as implementing health education for all migrant patients before chemotherapy and encouraging primary care workers to supervise patients. PMID:23284993

A Prestressed Cable Network Model of the Adherent Cell Cytoskeleton

PubMed Central

Coughlin, Mark F.; Stamenović, Dimitrije

2003-01-01

A prestressed cable network is used to model the deformability of the adherent cell actin cytoskeleton. The overall and microstructural model geometries and cable mechanical properties were assigned values based on observations from living cells and mechanical measurements on isolated actin filaments, respectively. The models were deformed to mimic cell poking (CP), magnetic twisting cytometry (MTC) and magnetic bead microrheometry (MBM) measurements on living adherent cells. The models qualitatively and quantitatively captured the fibroblast cell response to the deformation imposed by CP while exhibiting only some qualitative features of the cell response to MTC and MBM. The model for CP revealed that the tensed peripheral actin filaments provide the key resistance to indentation. The actin filament tension that provides mechanical integrity to the network was estimated at ∼158 pN, and the nonlinear mechanical response during CP originates from filament kinematics. The MTC and MBM simulations revealed that the model is incomplete, however, these simulations show cable tension as a key determinant of the model response. PMID:12547813

A prestressed cable network model of the adherent cell cytoskeleton.

PubMed

Coughlin, Mark F; Stamenović, Dimitrije

2003-02-01

A prestressed cable network is used to model the deformability of the adherent cell actin cytoskeleton. The overall and microstructural model geometries and cable mechanical properties were assigned values based on observations from living cells and mechanical measurements on isolated actin filaments, respectively. The models were deformed to mimic cell poking (CP), magnetic twisting cytometry (MTC) and magnetic bead microrheometry (MBM) measurements on living adherent cells. The models qualitatively and quantitatively captured the fibroblast cell response to the deformation imposed by CP while exhibiting only some qualitative features of the cell response to MTC and MBM. The model for CP revealed that the tensed peripheral actin filaments provide the key resistance to indentation. The actin filament tension that provides mechanical integrity to the network was estimated at approximately 158 pN, and the nonlinear mechanical response during CP originates from filament kinematics. The MTC and MBM simulations revealed that the model is incomplete, however, these simulations show cable tension as a key determinant of the model response.

A multidisciplinary approach to study the functional properties of neuron-like cell models constituting a living bio-hybrid system: SH-SY5Y cells adhering to PANI substrate

NASA Astrophysics Data System (ADS)

Caponi, S.; Mattana, S.; Ricci, M.; Sagini, K.; Juarez-Hernandez, L. J.; Jimenez-Garduño, A. M.; Cornella, N.; Pasquardini, L.; Urbanelli, L.; Sassi, P.; Morresi, A.; Emiliani, C.; Fioretto, D.; Dalla Serra, M.; Pederzolli, C.; Iannotta, S.; Macchi, P.; Musio, C.

2016-11-01

A living bio-hybrid system has been successfully implemented. It is constituted by neuroblastic cells, the SH-SY5Y human neuroblastoma cells, adhering to a poly-anyline (PANI) a semiconductor polymer with memristive properties. By a multidisciplinary approach, the biocompatibility of the substrate has been analyzed and the functionality of the adhering cells has been investigated. We found that the PANI films can support the cell adhesion. Moreover, the SH-SY5Y cells were successfully differentiated into neuron-like cells for in vitro applications demonstrating that PANI can also promote cell differentiation. In order to deeply characterize the modifications of the bio-functionality induced by the cell-substrate interaction, the functional properties of the cells have been characterized by electrophysiology and Raman spectroscopy. Our results confirm that the PANI films do not strongly affect the general properties of the cells, ensuring their viability without toxic effects on their physiology. Ascribed to the adhesion process, however, a slight increase of the markers of the cell suffering has been evidenced by Raman spectroscopy and accordingly the electrophysiology shows a reduction at positive stimulations in the cells excitability.

Noninvasive measurement of three-dimensional morphology of adhered animal cells employing phase-shifting laser microscope.

PubMed

Takagi, Mutsumi; Kitabayashi, Takayuki; Ito, Syunsuke; Fujiwara, Masashi; Tokuda, Akio

2007-01-01

Noninvasive measurement of 3-D morphology of adhered animal cells employing a phase-shifting laser microscope (PLM) is investigated, in which the phase shift for each pixel in the view field caused by cell height and the difference in refractive indices between the cells and the medium is determined. By employing saline with different refractive indices instead of a culture medium, the refractive index of the cells, which is necessary for the determination of cell height, is determined under PLM. The observed height of Chinese hamster ovary (CHO) cells cultivated under higher osmolarity is lower than that of the cells cultivated under physiological osmolarity, which is in agreement with previous data observed under an atomic force microscope (AFM). Maximum heights of human bone marrow mesenchymal stem cells and human umbilical cord vein endothelial cells measured under PLM and AFM agree well with each other. The maximum height of nonadherent spherical CHO cells observed under PLM is comparable to the cell diameter measured under a phase contrast inverted microscope. Laser irradiation, which is necessary for the observation under PLM, did not affect 3-D cell morphology. In conclusion, 3-D morphology of adhered animal cells can be noninvasively measured under PLM.

In vitro effects of ambroxol on Cryptococcus adherence, planktonic cells, and biofilms.

PubMed

Kong, Qingtao; Du, Xue; Huang, Suyang; Yang, Rui; Zhang, Chengzhen; Shen, Yongnian; Liu, Weida; Sang, Hong

2017-07-01

The antifungal effects of ambroxol (Amb; the metabolite VIII of bromhexine) against Cryptococcus planktonic cells and mature biofilms were investigated in this study. Amb showed antifungal activity against planktonic cells and mature biofilms. Disk diffusion test similarly showed antifungal profile for planktonic cells. Furthermore, Amb was found to be synergetic with fluconazole against planktonic cells and reduced the adherence of cells to polystyrene. Our results suggest that Amb can inhibit cryptococcal cells and biofilms, indicating its potential role in the prevention and treatment of cryptococcosis. © 2017 APMIS. Published by John Wiley & Sons Ltd.

Highly Tumorigenic Diffuse Large B Cell Lymphoma Cells Are Produced by Coculture with Stromal Cells.

PubMed

Lin, Zhiguang; Chen, Bobin; Wu, Ting; Xu, Xiaoping

2018-05-23

Diffuse large B cell lymphoma (DLBCL) is heterogeneous. We aimed to explore how tumor microenvironment promotes lymphoma cell aggressiveness and heterogeneity. We created a coculture system using human DLBCL cells and mouse bone marrow stromal cells. Proliferative capacity, drug resistance, clonogenicity, and tumorigenicity were compared in lymphoma cells from the coculture system and lymphoma cells cultured alone. Expression of Notch signaling associated genes was evaluated using real-time reverse transcriptase PCR and Western blot. Lymphoma cells in the coculture system differentiated into a suspended cell group and an adherent cell group. They acquired a stronger proliferative capacity and drug resistance than lymphoma cells cultured alone, and differences existed between the adherent cell and suspended cell groups. The suspended cell group acquired the most powerful clonogenic and tumorigenic potential. However, Notch3 was exclusively expressed in the adherent lymphoma cell group and the use of N-[N-(3, 5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester, an inhibitor of Notch pathway, could abolish the emergence of highly aggressive lymphoma cells. Highly tumorigenic lymphoma cells could be generated by coculture with stromal cells, and it was dependent on Notch3 expression in the adjacent lymphoma cells through interaction with stromal cells. © 2018 S. Karger AG, Basel.

Fathers’ Involvement in Preadolescents’ Diabetes Adherence and Glycemic Control*

PubMed Central

Rohan, Jennifer M.; Carle, Adam C.; Pendley, Jennifer Shroff; Delamater, Alan; Drotar, Dennis

2011-01-01

Objective To examine the relationship of paternal involvement in diabetes care with adherence and glycemic control. Methods One hundred and thirty-six mothers and fathers of preadolescents (aged 9–12 years) with type 1 diabetes reported on paternal involvement. Adherence was measured by interview and blood glucose meter downloads. Mothers’ and fathers’ ratings of paternal involvement in diabetes care were compared. We evaluated three structural equation models linking paternal involvement with adherence and glycemic control. Results Mothers and fathers reported similar amounts of paternal involvement, yet mothers rated paternal involvement as more helpful. The data supported a model indicating links between more paternal involvement and higher HbA1c and between lower adherence and higher HbA1c. Mediation and moderation models were not supported. Discussion Although paternal involvement was not directly associated with treatment adherence, it was associated with poorer glycemic control. Some fathers may increase their involvement in response to suboptimal glycemic outcomes. PMID:21515643

Therapeutic drug monitoring of boosted PIs in HIV-positive patients: undetectable plasma concentrations and risk of virological failure.

PubMed

Calcagno, A; Pagani, N; Ariaudo, A; Arduino, G; Carcieri, C; D'Avolio, A; Marinaro, L; Tettoni, M C; Trentini, L; Di Perri, G; Bonora, S

2017-06-01

Therapeutic drug monitoring (TDM) of antiretroviral drugs is performed in selected HIV-positive patients. The aim of this study was to estimate the prevalence of undetectable plasma concentrations of ritonavir and boosted PIs and to evaluate the association between those and the 48 week risk of virological failure. A TDM registry study and a retrospective follow-up study were conducted. Plasma concentrations were measured through validated methods. According to PI and ritonavir concentrations, patients were stratified as adherent, partially non-adherent or non-adherent. Virological outcome was evaluated 48 weeks afterwards. The TDM registry study included 2468 samples collected from 723 patients (68.1% male, median age 43.5 years). Eighty-seven samples (3.5%, 74 patients) and 68 samples (2.8%, 52 patients) were in the partially non-adherent and non-adherent groups, respectively; more patients on atazanavir/ritonavir (7.9%) versus darunavir/ritonavir (2% twice daily and 1.9% once daily) and lopinavir/ritonavir (1.5%; P  <   0.001) were observed in the partially non-adherent group. Two hundred and ninety patients were included in the follow-up study (64.1% male, median age 40 years). Patients in the adherent group had a higher chance of viral control [81.9% (167/204)] versus the partially non-adherent group and the non-adherent group [71.7% (33/46) and 53.1% (17/32), respectively; P  =   0.001]. Based on multivariate analysis, baseline HIV RNA >50 copies/mL ( P  <   0.001), genotypic susceptibility score ≤2 ( P  =   0.001), lower nadir CD4 cell count ( P  =   0.003) and not being in the adherent group ( P  =   0.029) were independent predictors of HIV RNA >50 copies/mL at 48 weeks. The measurement of PI and ritonavir plasma levels can uncover incomplete compliance with treatment; TDM may represent a useful tool for identifying patients in need of adherence-promoting interventions. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Fibrin monomer increases platelet adherence to tumor cells in a flowing system: a possible role in metastasis?

PubMed

Biggerstaff, J P; Seth, N B; Meyer, T V; Amirkhosravi, A; Francis, J L

1998-12-15

Considerable evidence exists linking hemostasis and malignancy. Platelet adhesion to tumor cells has been implicated in the metastatic process. Plasma fibrinogen (Fg) and fibrin (Fn) monomer, increased in cancer, may play a role in tumor biology. Binding of Fn monomer to tumor cells and its effect on platelet-tumor cell adhesion in a flowing system were studied. Fn monomer was produced by adding thrombin (1 micro/mL) to FXIII- and plasminogen-free Fg in the presence of Gly-Pro-Arg-Pro (GPRP) amide. Fn monomer binding to live A375 cells was visualized by confocal laser scanning microscopy (CLSM). Adherent cells were perfused for 1h with Fn monomer, washed and stained in situ with anti-human Fn (American Biogenetic Sciences, Inc.) followed by goat anti-mouse IgG(FITC). Platelet adherence to Fn monomer treated A375 cells was performed under flow conditions by passing platelets (5x10(4)/microl 0.25 mL/min; labeled with the carbocyanine dye DiI) over the tumor cells for 30 min. CLSM images were obtained after washing. There was considerable binding of Fn monomer, but not Fg alone. Platelets adhered relatively weakly to untreated A375 cells and this was not significantly affected by pre-treatment of the tumor cells with fibrinogen or thrombin. However, pre-treatment with Fn monomer resulted in extensive platelet binding to tumor cells, suggesting that coagulation activation and the subsequent increase in circulating Fn monomer may enhance platelet adhesion to circulating tumor cells and thereby facilitate metastatic spread.

Motivational interviewing targeting diet and physical activity improves adherence to pediatric obesity treatment: Results from the MI Values randomized controlled trial

PubMed Central

Bean, Melanie K.; Powell, Priscilla; Quinoy, Alexis; Ingersoll, Karen; Wickham, Edmond P.; Mazzeo, Suzanne E.

2014-01-01

Background Adherence is a challenge in obesity treatment. Motivational interviewing (MI) may promote patient adherence. MI Values is a randomized controlled trial of MI implemented as an adjunct to an adolescent obesity treatment (T.E.E.N.S.). Objective Assess effects of MI Values on T.E.E.N.S. attrition and adherence. Methods Participants were randomized to MI (n=58) or control (n=41). At weeks 1 and 10, MI participants had brief MI sessions; controls viewed health education videos. All participants continued with T.E.E.N.S. (biweekly dietitian and behavioral support visits; 3x/week supervised physical activity). Assessments were repeated at baseline, 3 and 6-months. T-tests and chi-square analyses examined T.E.E.N.S. attrition and adherence by group. Results Adolescents (N=99) were primarily African American (73%) females (74%); age=13.8±1.8 years, body mass index percentile=98.0±1.2. Compared with controls, MI participants had greater 3-month adherence overall (89.2% vs. 81.0%, p=0.040), and to dietitian (91.3% vs. 84.0%; p=0.046) and behavioral support (92.9% vs. 85.2%; p=0.041) visits, and greater 6-month adherence overall (84.4% vs. 76.2%, p=0.026) and to behavioral support visits (87.5% vs. 78.8%, p=0.011). Conclusions MI enhanced adherence to this obesity intervention. MI Values is the first study to examine the impact of MI on treatment adherence among obese, primarily African American adolescents. PMID:24729537

Assessing adherence in the CAPRISA 004 tenofovir gel HIV prevention trial: results of a nested case-control study.

PubMed

MacQueen, Kathleen M; Weaver, Mark A; van Loggerenberg, Francois; Succop, Stacey; Majola, Nelisle; Taylor, Doug; Karim, Quarraisha Abdool; Karim, Salim Abdool

2014-05-01

Adherence undeniably impacts product effectiveness in microbicide trials, but the connection has proven challenging to quantify using routinely collected behavioral data. We explored this relationship using a nested case-control study in the CAPRISA 004 Tenofovir (TFV) gel HIV prevention trial. Detailed 3-month recall data on sex events, condom and gel use were collected from 72 incident cases and 205 uninfected controls. We then assessed how the relationship between self-reported adherence and HIV acquisition differed between the TFV and placebo gel groups, an interaction effect that should exist if effectiveness increases with adherence. The CAPRISA 004 trial determined that randomization to TFV gel was associated with a significant reduction in risk of HIV acquisition. In our nested case-control study, however, we did not observe a meaningful decrease in the relative odds of infection-TFV versus placebo-as self-reported adherence increased. To the contrary, exploratory sub-group analysis of the case-control data identified greater evidence for a protective effect of TFV gel among participants reporting less than 80 % adherence to the protocol-defined regimen (odds ratio (OR) 0.30; 95 % CI 0.11-0.78) than among those reporting ≥ 80 % adherence (Odds Ratio 0.81; 95 % CI 0.34-1.92). The small number of cases may have inhibited our ability to detect the hypothesized interaction between adherence and effectiveness. Nonetheless, our results re-emphasize the challenges faced by investigators when adherence may be miss-measured, miss-reported, or confounded with the risk of HIV.

Development of a shear stress-free microfluidic gradient generator capable of quantitatively analyzing single-cell morphology.

PubMed

Barata, David; Spennati, Giulia; Correia, Cristina; Ribeiro, Nelson; Harink, Björn; van Blitterswijk, Clemens; Habibovic, Pamela; van Rijt, Sabine

2017-09-07

Microfluidics, the science of engineering fluid streams at the micrometer scale, offers unique tools for creating and controlling gradients of soluble compounds. Gradient generation can be used to recreate complex physiological microenvironments, but is also useful for screening purposes. For example, in a single experiment, adherent cells can be exposed to a range of concentrations of the compound of interest, enabling high-content analysis of cell behaviour and enhancing throughput. In this study, we present the development of a microfluidic screening platform where, by means of diffusion, gradients of soluble compounds can be generated and sustained. This platform enables the culture of adherent cells under shear stress-free conditions, and their exposure to a soluble compound in a concentration gradient-wise manner. The platform consists of five serial cell culture chambers, all coupled to two lateral fluid supply channels that are used for gradient generation through a source-sink mechanism. Furthermore, an additional inlet and outlet are used for cell seeding inside the chambers. Finite element modeling was used for the optimization of the design of the platform and for validation of the dynamics of gradient generation. Then, as a proof-of-concept, human osteosarcoma MG-63 cells were cultured inside the platform and exposed to a gradient of Cytochalasin D, an actin polymerization inhibitor. This set-up allowed us to analyze cell morphological changes over time, including cell area and eccentricity measurements, as a function of Cytochalasin D concentration by using fluorescence image-based cytometry.

Optical painting and fluorescence activated sorting of single adherent cells labelled with photoswitchable Pdots

PubMed Central

Kuo, Chun-Ting; Thompson, Alison M.; Gallina, Maria Elena; Ye, Fangmao; Johnson, Eleanor S.; Sun, Wei; Zhao, Mengxia; Yu, Jiangbo; Wu, I-Che; Fujimoto, Bryant; DuFort, Christopher C.; Carlson, Markus A.; Hingorani, Sunil R.; Paguirigan, Amy L.; Radich, Jerald P.; Chiu, Daniel T.

2016-01-01

The efficient selection and isolation of individual cells of interest from a mixed population is desired in many biomedical and clinical applications. Here we show the concept of using photoswitchable semiconducting polymer dots (Pdots) as an optical ‘painting' tool, which enables the selection of certain adherent cells based on their fluorescence, and their spatial and morphological features, under a microscope. We first develop a Pdot that can switch between the bright (ON) and dark (OFF) states reversibly with a 150-fold contrast ratio on irradiation with ultraviolet or red light. With a focused 633-nm laser beam that acts as a ‘paintbrush' and the photoswitchable Pdots as the ‘paint', we select and ‘paint' individual Pdot-labelled adherent cells by turning on their fluorescence, then proceed to sort and recover the optically marked cells (with 90% recovery and near 100% purity), followed by genetic analysis. PMID:27118210

Trichomonas vaginalis Contact-Dependent Cytolysis of Epithelial Cells

PubMed Central

Lustig, Gila; Ryan, Christopher M.; Secor, W. Evan

2013-01-01

Trichomonas vaginalis is an extracellular protozoan parasite that binds to the epithelium of the human urogenital tract during infection. In this study, we examined the propensities of 26 T. vaginalis strains to bind to and lyse prostate (BPH-1) and ectocervical (Ect1) epithelium and to lyse red blood cells (RBCs). We found that only three of the strains had a statistically significant preference for either BPH-1 (MSA1103) or Ect1 (LA1 and MSA1123). Overall, we observed that levels of adherence are highly variable among strains, with a 12-fold range of adherence on Ect1 cells and a 45-fold range on BPH-1 cells. Cytolysis levels displayed even greater variability, from no detectable cytolysis to 80% or 90% cytolysis of Ect1 and BPH-1, respectively. Levels of adherence and cytolysis correlate for weakly adherent/cytolytic strains, and a threshold of attachment was found to be necessary to trigger cytolysis; however, this threshold can be reached without inducing cytolysis. Furthermore, cytolysis was completely blocked when we prevented attachment of the parasites to host cells while allowing soluble factors complete access. We demonstrate that hemolysis was a rare trait, with only 4 of the 26 strains capable of lysing >20% RBCs with a 1:30 parasite/RBC ratio. Hemolysis also did not correlate with adherence to or cytolysis of either male (BPH-1)- or female (Ect1)-derived epithelial cell lines. Our results reveal that despite a broad range of pathogenic properties among different T. vaginalis strains, all strains show strict contact-dependent cytolysis. PMID:23429535

The Effect of Education through Short Message Service (SMS) Messages on Diabetic Patients Adherence

PubMed Central

Adikusuma, Wirawan; Qiyaam, Nurul

2017-01-01

Poor adherence and a lack of understanding of medication instructions for oral antidiabetic use are key factors that inhibit the control of glycemic levels. The aforementioned situation needs intervention to improve medication adherence and the therapy. This study was conducted with a quasi-experimental design with prospective data collection. The subjects of this study were 50 outpatients with type 2 diabetes melitus (T2DM) who had received oral antidiabetic medicine therapy at least six months prior to adherence measurement. The patients were classified into two groups—the control group and the intervention group. The intervention group received Short Message Service (SMS) messages of diabetes education, while the control group did not. Data collection was conducted by doing interviews and administering the Morisky Medication Adherence Scale (MMAS) questionnaire. The results showed the increase in adherence in the intervention group as 1.15 ± 1.04 and that in the control group as 0.72 ± 0.90. These results indicated that there were significant differences in MMAS score between the control and intervention groups (p < 0.05). The decrease in fasting blood glucose and glucose measured 2 h postprandially was greater in the intervention group than that in the control group. It was concluded that the provision of education through SMS had a positive effect on medication adherence and glycemic levels. PMID:28545222

The Effect of Education through Short Message Service (SMS) Messages on Diabetic Patients Adherence.

PubMed

Adikusuma, Wirawan; Qiyaam, Nurul

2017-05-12

Poor adherence and a lack of understanding of medication instructions for oral antidiabetic use are key factors that inhibit the control of glycemic levels. The aforementioned situation needs intervention to improve medication adherence and the therapy. This study was conducted with a quasi-experimental design with prospective data collection. The subjects of this study were 50 outpatients with type 2 diabetes melitus (T2DM) who had received oral antidiabetic medicine therapy at least six months prior to adherence measurement. The patients were classified into two groups-the control group and the intervention group. The intervention group received Short Message Service (SMS) messages of diabetes education, while the control group did not. Data collection was conducted by doing interviews and administering the Morisky Medication Adherence Scale (MMAS) questionnaire. The results showed the increase in adherence in the intervention group as 1.15 ± 1.04 and that in the control group as 0.72 ± 0.90. These results indicated that there were significant differences in MMAS score between the control and intervention groups ( p < 0.05). The decrease in fasting blood glucose and glucose measured 2 h postprandially was greater in the intervention group than that in the control group. It was concluded that the provision of education through SMS had a positive effect on medication adherence and glycemic levels.

Intact LKB1 activity is required for survival of dormant ovarian cancer spheroids

PubMed Central

Peart, Teresa; Valdes, Yudith Ramos; Correa, Rohann J. M.; Fazio, Elena; Bertrand, Monique; McGee, Jacob; Préfontaine, Michel; Sugimoto, Akira; DiMattia, Gabriel E.; Shepherd, Trevor G.

2015-01-01

Metastatic epithelial ovarian cancer (EOC) cells can form multicellular spheroids while in suspension and disperse directly throughout the peritoneum to seed secondary lesions. There is growing evidence that EOC spheroids are key mediators of metastasis, and they use specific intracellular signalling pathways to control cancer cell growth and metabolism for increased survival. Our laboratory discovered that AKT signalling is reduced during spheroid formation leading to cellular quiescence and autophagy, and these may be defining features of tumour cell dormancy. To further define the phenotype of EOC spheroids, we have initiated studies of the Liver kinase B1 (LKB1)-5′-AMP-activated protein kinase (AMPK) pathway as a master controller of the metabolic stress response. We demonstrate that activity of AMPK and its upstream kinase LKB1 are increased in quiescent EOC spheroids as compared with proliferating adherent EOC cells. We also show elevated AMPK activity in spheroids isolated directly from patient ascites. Functional studies reveal that treatment with the AMP mimetic AICAR or allosteric AMPK activator A-769662 led to a cytostatic response in proliferative adherent ovarian cancer cells, but they fail to elicit an effect in spheroids. Targeted knockdown of STK11 by RNAi to reduce LKB1 expression led to reduced viability and increased sensitivity to carboplatin treatment in spheroids only, a phenomenon which was AMPK-independent. Thus, our results demonstrate a direct impact of altered LKB1-AMPK signalling function in EOC. In addition, this is the first evidence in cancer cells demonstrating a pro-survival function for LKB1, a kinase traditionally thought to act as a tumour suppressor. PMID:26068970

Survival, differentiation, and neuroprotective mechanisms of human stem cells complexed with neurotrophin-3-releasing pharmacologically active microcarriers in an ex vivo model of Parkinson's disease.

PubMed

Daviaud, Nicolas; Garbayo, Elisa; Sindji, Laurence; Martínez-Serrano, Alberto; Schiller, Paul C; Montero-Menei, Claudia N

2015-06-01

Stem cell-based regenerative therapies hold great potential for the treatment of degenerative disorders such as Parkinson's disease (PD). We recently reported the repair and functional recovery after treatment with human marrow-isolated adult multilineage inducible (MIAMI) cells adhered to neurotrophin-3 (NT3) releasing pharmacologically active microcarriers (PAMs) in hemiparkinsonian rats. In order to comprehend this effect, the goal of the present work was to elucidate the survival, differentiation, and neuroprotective mechanisms of MIAMI cells and human neural stem cells (NSCs), both adhering to NT3-releasing PAMs in an ex vivo organotypic model of nigrostriatal degeneration made from brain sagittal slices. It was shown that PAMs led to a marked increase in MIAMI cell survival and neuronal differentiation when releasing NT3. A significant neuroprotective effect of MIAMI cells adhering to PAMs was also demonstrated. NSCs barely had a neuroprotective effect and differentiated mostly into dopaminergic neuronal cells when adhering to PAM-NT3. Moreover, those cells were able to release dopamine in a sufficient amount to induce a return to baseline levels. Reverse transcription-quantitative polymerase chain reaction and enzyme-linked immunosorbent assay analyses identified vascular endothelial growth factor (VEGF) and stanniocalcin-1 as potential mediators of the neuroprotective effect of MIAMI cells and NSCs, respectively. It was also shown that VEGF locally stimulated tissue vascularization, which might improve graft survival, without excluding a direct neuroprotective effect of VEGF on dopaminergic neurons. These results indicate a prospective interest of human NSC/PAM and MIAMI cell/PAM complexes in tissue engineering for PD. Stem cell-based regenerative therapies hold great potential for the treatment of degenerative disorders such as Parkinson's disease (PD). The present work elucidates and compares the survival, differentiation, and neuroprotective mechanisms of marrow-isolated adult multilineage inducible cells and human neural stem cells both adhered to neurotrophin-3-releasing pharmacologically active microcarriers in an ex vivo organotypic model of PD made from brain sagittal slices. ©AlphaMed Press.

The Pseudomonas aeruginosa exopolysaccharide Psl facilitates surface adherence and NF-kappaB activation in A549 cells.

PubMed

Byrd, Matthew S; Pang, Bing; Mishra, Meenu; Swords, W Edward; Wozniak, Daniel J

2010-06-29

In order for the opportunistic Gram-negative pathogen Pseudomonas aeruginosa to cause an airway infection, the pathogen interacts with epithelial cells and the overlying mucous layer. We examined the contribution of the biofilm polysaccharide Psl to epithelial cell adherence and the impact of Psl on proinflammatory signaling by flagellin. Psl has been implicated in the initial attachment of P. aeruginosa to biotic and abiotic surfaces, but its direct role in pathogenesis has not been evaluated (L. Ma, K. D. Jackson, R. M. Landry, M. R. Parsek, and D. J. Wozniak, J. Bacteriol. 188:8213-8221, 2006). Using an NF-kappaB luciferase reporter system in the human epithelial cell line A549, we show that both Psl and flagellin are necessary for full activation of NF-kappaB and production of the interleukin 8 (IL-8) chemokine. We demonstrate that Psl does not directly stimulate NF-kappaB activity, but indirectly as a result of increasing contact between bacterial cells and epithelial cells, it facilitates flagellin-mediated proinflammatory signaling. We confirm differential adherence of Psl and/or flagellin mutants by scanning electron microscopy and identify Psl-dependent membrane structures that may participate in adherence. Although we hypothesized that Psl would protect P. aeruginosa from recognition by the epithelial cell line A549, we instead observed a positive role for Psl in flagellin-mediated NF-kappaB activation, likely as a result of increasing contact between bacterial cells and epithelial cells.

The Pseudomonas aeruginosa Exopolysaccharide Psl Facilitates Surface Adherence and NF-κB Activation in A549 Cells

PubMed Central

Byrd, Matthew S.; Pang, Bing; Mishra, Meenu; Swords, W. Edward; Wozniak, Daniel J.

2010-01-01

In order for the opportunistic Gram-negative pathogen Pseudomonas aeruginosa to cause an airway infection, the pathogen interacts with epithelial cells and the overlying mucous layer. We examined the contribution of the biofilm polysaccharide Psl to epithelial cell adherence and the impact of Psl on proinflammatory signaling by flagellin. Psl has been implicated in the initial attachment of P. aeruginosa to biotic and abiotic surfaces, but its direct role in pathogenesis has not been evaluated (L. Ma, K. D. Jackson, R. M. Landry, M. R. Parsek, and D. J. Wozniak, J. Bacteriol. 188:8213–8221, 2006). Using an NF-κB luciferase reporter system in the human epithelial cell line A549, we show that both Psl and flagellin are necessary for full activation of NF-κB and production of the interleukin 8 (IL-8) chemokine. We demonstrate that Psl does not directly stimulate NF-κB activity, but indirectly as a result of increasing contact between bacterial cells and epithelial cells, it facilitates flagellin-mediated proinflammatory signaling. We confirm differential adherence of Psl and/or flagellin mutants by scanning electron microscopy and identify Psl-dependent membrane structures that may participate in adherence. Although we hypothesized that Psl would protect P. aeruginosa from recognition by the epithelial cell line A549, we instead observed a positive role for Psl in flagellin-mediated NF-κB activation, likely as a result of increasing contact between bacterial cells and epithelial cells. PMID:20802825

The Actinomyces oris Type 2 Fimbrial Shaft FimA Mediates Coaggregation with Oral Streptococci, Adherence to RBC and Biofilm Development

PubMed Central

Mishra, Arunima; Wu, Chenggang; Yang, Jinghua; Cisar, John O.; Das, Asis; Ton-That, Hung

2010-01-01

Interbacterial interactions between oral streptococci and actinomyces and their adherence to tooth surface and the associated host cells are key early events that promote development of the complex oral biofilm referred to as dental plaque. These interactions depend largely on a lectin-like activity associated with the Actinomyces oris type 2 fimbria, a surface structure assembled by sortase (SrtC2)-dependent polymerization of the shaft and tip fimbrillins, FimA and FimB, respectively. To dissect the function of specific fimbrillins in various adherence processes, we have developed a convenient new technology for generating unmarked deletion mutants of A. oris. Here, we show that the fimB mutant, which produced type 2 fimbriae composed only of FimA, like the wild type coaggregated strongly with receptor-bearing streptococci, agglutinated with sialidase-treated RBC, and formed monospecies biofilm. In contrast, the fimA and srtC2 mutants lacked type 2 fimbriae and were non-adherent in each of these assays. Plasmidbased expression of the deleted gene in respective mutants restored adherence to wild-type levels. These findings uncover the importance of the lectin-like activity of the polymeric FimA shaft rather than the tip. The multivalent adhesive function of FimA makes it an ideal molecule for exploring novel intervention strategies to control plaque biofilm formation. PMID:20545853

Effect of effort-reward imbalance and burnout on infection control among Ecuadorian nurses.

PubMed

Colindres, C V; Bryce, E; Coral-Rosero, P; Ramos-Soto, R M; Bonilla, F; Yassi, A

2018-06-01

Nurses are frequently exposed to transmissible infections, yet adherence to infection control measures is suboptimal. There has been inadequate research into how the psychosocial work environment affects compliance with infection control measures, especially in low- and middle-income countries. To examine the association between effort-reward imbalance, burnout and adherence to infection control measures among nurses in Ecuador. A cross-sectional study linking psychosocial work environment indicators to infection control adherence. The study was conducted among 333 nurses in four Ecuadorian hospitals. Self-administered questionnaires assessed demographic variables, perceived infection risk, effort-reward imbalance, burnout and infection control adherence. Increased effort-reward imbalance was found to be a unique incremental predictor of exposure to burnout, and burnout was a negative unique incremental predictor of nurses' self-reported adherence with infection control measures. Results suggest an effort-reward imbalance-burnout continuum, which, at higher levels, contributes to reduce adherence to infection control. The Ecuadorean government has made large efforts to improve universal access to health care, yet this study suggests that workplace demands on nurses remain problematic. This study highlights the contribution of effort-reward-imbalance-burnout continuum to the chain of infection by decreased adherence to infection control of nurses. Health authorities should closely monitor the effect of new policies on psychosocial work environment, especially when expanding services and increasing public accessibility with limited resources. Additionally, organizational and psychosocial interventions targeting effort-reward imbalance and burnout in nurses should be considered part of a complete infection prevention and control strategy. Further study is warranted to identify interventions that best ameliorate effort-reward imbalance and burnout in low- and middle-income settings. © 2017 The Authors International Nursing Review published by John Wiley & Sons Ltd on behalf of International Council of Nurses.

Surface design of antibody-immobilized thermoresponsive cell culture dishes for recovering intact cells by low-temperature treatment.

PubMed

Kobayashi, Jun; Hayashi, Masaki; Ohno, Takahiro; Nishi, Masanori; Arisaka, Yoshinori; Matsubara, Yoshinori; Kakidachi, Hiroshi; Akiyama, Yoshikatsu; Yamato, Masayuki; Horii, Akihiro; Okano, Teruo

2014-11-01

Antibody-immobilized thermoresponsive poly(N-isopropylacrylamide-co-2-carboxyisopropylacrylamide) [poly(IPAAm-co-CIPAAm)]-grafted cell culture surfaces were designed to enhance both the initial adhesion of weakly adhering cells and the ability of cells to detach in response to low temperature through the regulation of affinity binding between immobilized antibodies and antigens on the cellular surface. Ty-82 cells and neonatal normal human dermal fibroblasts (NHDFs), which express CD90 on the cell surface, adhered to anti-CD90 antibody-immobilized thermoresponsive surfaces at 37°C, a condition at which the grafted thermoresponsive polymer chains shrank. Adherent Ty-82 cells were detached from the surfaces by lowering the temperature to 20°C and applying external forces, such as pipetting, whereas cultured NHDF sheets spontaneously detached themselves from the surface in response to reduced temperature alone. When the temperature was decreased to 20°C, the swelling of grafted thermoresponsive polymer chains weakened the affinity binding between immobilized antibody and antigen on the cells due to the increasing steric hindrance of the polymer chains around the antigen-recognition site of the immobilized antibodies. No contamination was detected on cells harvested from covalently immobilized antibodies on the culture surfaces by low-temperature treatment, whereas a carryover of the antibody and avidin from the avidin-biotin binding surface was observed. Furthermore, the initial adhesion of adipose tissue-derived cells, which adhere weakly to PIPAAm-grafted surfaces, was enhanced on the antibody-immobilized thermoresponsive surfaces. © 2013 Wiley Periodicals, Inc.

Trimethylamine N-oxide in atherogenesis: impairing endothelial self-repair capacity and enhancing monocyte adhesion.

PubMed

Ma, GuoHua; Pan, Bing; Chen, Yue; Guo, CaiXia; Zhao, MingMing; Zheng, LeMin; Chen, BuXing

2017-04-30

Several studies have reported a strong association between high plasma level of trimethylamine N-oxide (TMAO) and atherosclerosis development. However, the exact mechanism underlying this correlation is unknown. In the present study, we try to explore the impact of TMAO on endothelial dysfunction. After TMAO treatment, human umbilical vein endothelial cells (HUVECs) showed significant impairment in cellular proliferation and HUVECs-extracellular matrix (ECM) adhesion compared with control. Likewise, TMAO markedly suppressed HUVECs migration in transwell migration assay and wound healing assay. In addition, we found TMAO up-regulated vascular cell adhesion molecule-1 (VCAM-1) expression, promoted monocyte adherence, activated protein kinase C (PKC) and p-NF-κB. Interestingly, TMAO-stimulated VCAM-1 expression and monocyte adherence were diminished by PKC inhibitor. These results demonstrate that TMAO promotes early pathological process of atherosclerosis by accelerating endothelial dysfunction, including decreasing endothelial self-repair and increasing monocyte adhesion. Furthermore, TMAO-induced monocyte adhesion is partly attributable to activation of PKC/NF-κB/VCAM-1. © 2017 The Author(s).

Randomized feasibility trial to improve hydroxyurea adherence in youth ages 10-18 years through community health workers: The HABIT study.

PubMed

Green, Nancy S; Manwani, Deepa; Matos, Sergio; Hicks, April; Soto, Luisa; Castillo, Yina; Ireland, Karen; Stennett, Yvonne; Findley, Sally; Jia, Haomiao; Smaldone, Arlene

2017-12-01

The main therapeutic intervention for sickle cell disease (SCD) is hydroxyurea (HU). The effect of HU is largely through dose-dependent induction of fetal hemoglobin (HbF). Poor HU adherence is common among adolescents. Our 6-month, two-site pilot intervention trial, "HABIT," was led by culturally aligned community health workers (CHWs). CHWs performed support primarily through home visits, augmented by tailored text message reminders. Dyads of youth with SCD ages 10-18 years and a parent were enrolled. A customized HbF biomarker, the percentage decrease from each patients' highest historical HU-induced HbF, "Personal best," was used to qualify for enrollment and assess HU adherence. Two primary outcomes were as follows: (1) intervention feasibility and acceptability and (2) HU adherence measured in three ways: monthly percentage improvement toward HbF Personal best, proportion of days covered (PDC) by HU, and self-report. Twenty-eight dyads were enrolled, of which 89% were retained. Feasibility and acceptability were excellent. Controlling for group assignment and month of intervention, the intervention group improved percentage decrease from Personal best by 2.3% per month during months 0-4 (P = 0.30), with similar improvement in adherence demonstrated using pharmacy records. Self-reported adherence did not correlate. Dyads viewed CHWs as supportive for learning about SCD and HU, living with SCD and making progress in coordinated self-management responsibility to support a daily HU habit. Most parents and youth appreciated text message HU reminders. The HABIT pilot intervention demonstrated feasibility and acceptability with promising effect toward improved medication adherence. Testing in a larger multisite intervention trial is warranted. © 2017 Wiley Periodicals, Inc.

Control of overweight and obesity in childhood through education in meal time habits. The 'good manners for a healthy future' programme.

PubMed

Salazar Vázquez, B Y; Salazar Vázquez, M A; López Gutiérrez, G; Acosta Rosales, K; Cabrales, P; Vadillo-Ortega, F; Intaglietta, M; Pérez Tamayo, R; Schmid-Schönbein, G W

2016-12-01

Our aim is to determine the effect of paced eating, exposure to an educational programme that promotes healthy eating habits and allowing the satiety reflex to limit food intake in controlling weight gain in healthy adolescents. Fifty-four healthy individuals consisting of 18 adolescent girls and 36 boys aged 12 ± 2 years were given recommendations for reducing eating rate without changing diet or meal size according to the educational programme 'good manners for a healthy future'. Each participant was provided with a 30-s portable hourglass to pace time between bites. Individuals using and not using the hourglass were placed either into an 'adhering' or a 'non-adhering' group, respectively. Control data were obtained from a similar population. Initially, the adhering group had higher weight compared with the non-adhering group (64.1 ± 13.2 vs. 56.2 ± 11.7 kg). Control group weight was no different from the study group at baseline (56.3 ± 10.3 kg). Weight in the adhering group decreased after the first semester of participation by 2.0 ± 5.7% and after a year by 3.4 ± 4.8%, while the non-adhering group gained weight by 5.8 ± 4.5% and 12.6 ± 8.3%. The control group increased weight after a year by 8.2 ± 6.5%. In total, 18 non-adhering and 14 adhering adolescents completed the study. This 1-year study shows a statistically significant association between rate of food intake and weight control in adherence to an educational programme directed at developing healthy eating habits. The proposed behavioural training may serve as an option for weight control in adolescents. © 2015 The Authors. Pediatric Obesity published by John Wiley & Sons Ltd on behalf of World Obesity Federation.

Decreased Superoxide Production, Degranulation, Tumor Necrosis Factor Alpha Secretion, and CD11b/CD18 Receptor Expression by Adherent Monocytes from Preterm Infants

PubMed Central

Kaufman, David; Kilpatrick, Laurie; Hudson, R. Guy; Campbell, Donald E.; Kaufman, Ann; Douglas, Steven D.; Harris, Mary C.

1999-01-01

Preterm infants have an increased incidence of infection, which is principally due to deficiencies in neonatal host defense mechanisms. Monocyte adherence is important in localizing cells at sites of infection and is associated with enhanced antimicrobial functions. We isolated cord blood monocytes from preterm and full-term infants to study their adhesion and immune functions, including superoxide (O2−) generation, degranulation, and cytokine secretion and their adhesion receptors. O2− production and degranulation were significantly diminished, by 28 and 37%, respectively, in adherent monocytes from preterm infants compared to full-term infants (P < 0.05); however, these differences were not seen in freshly isolated cells. We also observed a significant decrease of 35% in tumor necrosis factor alpha secretion by lipopolysaccharide-stimulated adherent monocytes from preterm infants compared to full-term infants (P < 0.05); however, this difference was not observed in interleukin-1β or interleukin-6 production by the monocytes. The cell surface expression of the CD11b/CD18 adhesion receptor subunits was significantly decreased (by 60 and 52%, respectively) in monocytes from preterm infants compared to full-term infants (P < 0.01). The cascade of the immune response to infection involves monocyte upregulation and adherence via CD11b/CD18 receptors followed by cell activation and the release of cytokines and bactericidal products. We speculate that monocyte adherence factors may be important in the modulation of immune responses in preterm infants. PMID:10391855

Coping with Treatment-Related Stress: Effects on Patient Adherence in Hemodialysis.

ERIC Educational Resources Information Center

Christensen, Alan J.; And Others

1995-01-01

Examines the relation of coping to adherence among 57 hemodialysis patients. As predicted, coping efforts involving planful problem solving were associated with more favorable adherence when used in response to stressors involving a relatively controllable aspect of the hemodialysis context. For less controllable stressors, coping efforts…

Dietary Adherence Monitoring Tool for Free-living, Controlled Feeding Studies

USDA-ARS?s Scientific Manuscript database

Objective: To devise a dietary adherence monitoring tool for use in controlled human feeding trials involving free-living study participants. Methods: A scoring tool was devised to measure and track dietary adherence for an 8-wk randomized trial evaluating the effects of two different dietary patter...

Human aortic endothelial cell morphology influenced by topography of porous silicon substrates.

PubMed

Formentín, Pilar; Catalán, Úrsula; Fernández-Castillejo, Sara; Alba, Maria; Baranowska, Malgorzata; Solà, Rosa; Pallarès, Josep; Marsal, Lluís F

2015-10-01

Porous silicon has received much attention because of its optical properties and for its usefulness in cell-based biosensing, drug delivery, and tissue engineering applications. Surface properties of the biomaterial are associated with cell adhesion and with proliferation, migration, and differentiation. The present article analyzes the behavior of human aortic endothelial cells in macro- and nanoporous collagen-modified porous silicon samples. On both substrates, cells are well adhered and numerous. Confocal microscopy and scanning electron microscopy were employed to study the effects of porosity on the morphology of the cells. On macroporous silicon, filopodia is not observed but the cell spreads on the surface, increasing the lamellipodia surface which penetrates the macropore. On nanoporous silicon, multiple filopodia were found to branch out from the cell body. These results demonstrate that the pore size plays a key role in controlling the morphology and growth rate of human aortic endothelial cells, and that these forms of silicon can be used to control cell development in tissue engineering as well as in basic cell biology research. © The Author(s) 2015.

Under a nonadherent state, bone marrow mesenchymal stem cells can be efficiently induced into functional islet-like cell clusters to normalize hyperglycemia in mice: a control study.

PubMed

Zhang, Yihua; Dou, Zhongying

2014-05-08

Bone marrow mesenchymal stem cells (BMSCs) possess low immunogenicity and immunosuppression as an allograft, can differentiate into insulin-producing cells (IPCs) by in vitro induction, and may be a valuable cell source to regenerate pancreatic islets. However, the very low differentiation efficiency of BMSCs towards IPCs under adherent induction has thus far hindered the clinical exploitation of these cells. The aim of this study is to explore a new way to efficiently induce BMSCs into IPCs and lay the groundwork for their clinical exploitation. In comparison with adherent induction, BMSCs of human first-trimester abortus (hfBMSCs) under a nonadherent state were induced towards IPCs in noncoated plastic dishes using a three-stage induction procedure developed by the authors. Induction effects were evaluated by statistics of the cell clustering rate of induced cells, and ultrastructural observation, dithizone staining, quantitative polymerase chain reaction and immunofluorescence assay, insulin and c-peptide release under glucose stimulus of cell clusters, as well as transplantation test of the cell clusters in diabetic model mice. With (6.175 ± 0.263) × 105 cells in 508.5 ± 24.5 cell clusters, (3.303 ± 0.331) × 105 single cells and (9.478 ± 0.208) × 105 total cell count on average, 65.08 ± 2.98% hfBMSCs differentiated into pancreatic islet-like cell clusters after nonadherent induction. With (3.993 ± 0.344) × 105 cells in 332.3 ± 41.6 cell clusters, (5.437 ± 0.434) × 105 single cells and (9.430 ± 0.340) × 105 total cell count on average, 42.37 ± 3.70% hfBMSCs differentiated into pancreatic islet-like cell clusters after adherent induction (P < 0.01, n = 10). The former is significantly higher than the latter. Calculated according to the cell clustering rate and IPC percentage in the cell clusters, 29.80 ± 3.95% hfBMSCs differentiated into IPCs after nonadherent induction and 18.40 ± 2.08% hfBMSCs differentiated into IPCs after adherent induction (P < 0.01, n = 10), the former significantly higher than the latter. The cell clusters expressed a broad gene profile related to pancreatic islet cells, released insulin and c-peptide in a glucose concentration-dependent manner, and normalized hyperglycemia of streptozocin-induced mice for at least 80 days following xenograft. Blood glucose of grafted mice rose again after their graft removed. A series of examination of the grafts showed that transplanted cells produced human insulin in recipients. Our studies demonstrate that nonadherent induction can greatly promote BMSCs to form pancreatic islet-like cell clusters, thereby improving the differentiation efficiency of BMSCs towards IPCs.

Work-Related Barriers and Facilitators to Antiretroviral Therapy Adherence in Persons Living with HIV Infection

PubMed Central

Torres-Madriz, Gilberto; Lerner, Debra; Ruthazer, Robin; Rogers, William H.; Wilson, Ira B.

2013-01-01

Little is known about how the structure of work affects adherence to HIV antiretroviral therapy. We surveyed participants in an adherence intervention study to learn more about job characteristics, including measures of psychological demand and control, and job accommodations. Adherence was assessed using the Medication Event Monitoring System (MEMS). Of 156 trial subjects, 69 were employed, and these 69 made 229 study visits. Psychological demands and control were unrelated to adherence, but the presence of workplace accommodations was significantly associated with adherence (p <0.05). In multivariable models adjusting for clustering, those who reported having received an accommodation were 12% more adherent than those who did not receive an accommodation. Adherence was unrelated to experiencing side effects affecting work performance. Having the ability to institute job accommodations was more important to adherence than the psychosocial structure of the work. These potential benefits of requesting modifications need to be weighed against the possible risks of workplace disclosure. PMID:20091340

Rho-ROCK signaling differentially regulates chondrocyte spreading on fibronectin and bone sialoprotein.

PubMed

Gill, Kamal S; Beier, Frank; Goldberg, Harvey A

2008-07-01

The mammalian growth plate is a dynamic structure rich in extracellular matrix (ECM). Interactions of growth plate chondrocytes with ECM proteins regulate cell behavior. In this study, we compared chondrocyte adhesion and spreading dynamics on fibronectin (FN) and bone sialoprotein (BSP). Chondrocyte adhesion and spreading were also compared with fibroblasts to analyze potential cell-type-specific effects. Chondrocyte adhesion to BSP is independent of posttranslational modifications but is dependent on the RGD sequence in BSP. Whereas chondrocytes and fibroblasts adhered at similar levels on FN and BSP, cells displayed more actin-dependent spread on FN despite a 16x molar excess of BSP adsorbed to plastic. To identify intracellular mediators responsible for this difference in spreading, we investigated focal adhesion kinase (FAK)-Src and Rho-Rho kinase (ROCK) signaling. Although activated FAK localized to the vertices of adhered chondrocytes, levels of FAK activation did not correlate with the extent of spreading. Furthermore, Src inhibition reduced chondrocyte spreading on both FN and BSP, suggesting that FAK-Src signaling is not responsible for less cell spreading on BSP. In contrast, inhibition of Rho and ROCK in chondrocytes increased cell spreading on BSP and membrane protrusiveness on FN but did not affect cell adhesion. In fibroblasts, Rho inhibition increased fibroblast spreading on BSP while ROCK inhibition changed membrane protrusiveness of FN and BSP. In summary, we identify a novel role for Rho-ROCK signaling in regulating chondrocyte spreading and demonstrate both cell- and matrix molecule-specific mechanisms controlling cell spreading.

Rho-ROCK signaling differentially regulates chondrocyte spreading on fibronectin and bone sialoprotein

PubMed Central

Gill, Kamal S.; Beier, Frank; Goldberg, Harvey A.

2008-01-01

The mammalian growth plate is a dynamic structure rich in extracellular matrix (ECM). Interactions of growth plate chondrocytes with ECM proteins regulate cell behavior. In this study, we compared chondrocyte adhesion and spreading dynamics on fibronectin (FN) and bone sialoprotein (BSP). Chondrocyte adhesion and spreading were also compared with fibroblasts to analyze potential cell-type-specific effects. Chondrocyte adhesion to BSP is independent of posttranslational modifications but is dependent on the RGD sequence in BSP. Whereas chondrocytes and fibroblasts adhered at similar levels on FN and BSP, cells displayed more actin-dependent spread on FN despite a 16× molar excess of BSP adsorbed to plastic. To identify intracellular mediators responsible for this difference in spreading, we investigated focal adhesion kinase (FAK)-Src and Rho-Rho kinase (ROCK) signaling. Although activated FAK localized to the vertices of adhered chondrocytes, levels of FAK activation did not correlate with the extent of spreading. Furthermore, Src inhibition reduced chondrocyte spreading on both FN and BSP, suggesting that FAK-Src signaling is not responsible for less cell spreading on BSP. In contrast, inhibition of Rho and ROCK in chondrocytes increased cell spreading on BSP and membrane protrusiveness on FN but did not affect cell adhesion. In fibroblasts, Rho inhibition increased fibroblast spreading on BSP while ROCK inhibition changed membrane protrusiveness of FN and BSP. In summary, we identify a novel role for Rho-ROCK signaling in regulating chondrocyte spreading and demonstrate both cell- and matrix molecule-specific mechanisms controlling cell spreading. PMID:18463228

Psychosocial and cognitive factors associated with adherence to dietary and fluid restriction regimens by people on chronic haemodialysis.

PubMed

Sensky, T; Leger, C; Gilmour, S

1996-01-01

Failure by people on chronic haemodialysis to adhere adequately to dietary and fluid restrictions can have serious medical consequences. Numerous psychosocial factors possibly associated with adherence have been investigated in previous research. However, most previous studies have examined one or a few variables in isolation, and have tended to focus on sociodemographic variables not easily amenable to intervention. Much previous work has tended to ignore potential differences in adherence between male and female dialysands. Sociodemographic and psychosocial factors associated with adherence to dietary and fluid restrictions were investigated in 45 people on haemodialysis attending one renal unit, excluding those with a residual urine volume > 500 ml/day. Multiple regression analyses were used to estimate the contribution to adherence of a range of variables, including gender, age, duration of dialysis, affective disturbance, past psychiatric history, health locus of control, social adjustment and social supports. Adherence to diet (measured by predialysis serum potassium) and to fluid restriction (interdialysis weight gain) were not linked, and had different psychosocial correlates. Regression models of four different aspects of adherence revealed very distinct psychosocial correlates, with contributions to adherence from complex interactions between psychosocial and cognitive variables, notably gender, age, social adjustment, health locus of control, and depression. The findings cast doubt on the results of many previous studies which have used simple models of adherence. Adherence is likely to be influenced in a complex manner by multiple factors including age, gender, locus of control, social adjustment, and past psychiatric history.

siRNA Nanoparticle Functionalization of Nanostructured Scaffolds Enables Controlled Multilineage Differentiation of Stem Cells

PubMed Central

Andersen, Morten Ø; Nygaard, Jens V; Burns, Jorge S; Raarup, Merete K; Nyengaard, Jens R; Bünger, Cody; Besenbacher, Flemming; Howard, Kenneth A; Kassem, Moustapha; Kjems, Jørgen

2010-01-01

The creation of complex tissues and organs is the ultimate goal in tissue engineering. Engineered morphogenesis necessitates spatially controlled development of multiple cell types within a scaffold implant. We present a novel method to achieve this by adhering nanoparticles containing different small-interfering RNAs (siRNAs) into nanostructured scaffolds. This allows spatial retention of the RNAs within nanopores until their cellular delivery. The released siRNAs were capable of gene silencing BCL2L2 and TRIB2, in mesenchymal stem cells (MSCs), enhancing osteogenic and adipogenic differentiation, respectively. This approach for enhancing a single type of differentiation is immediately applicable to all areas of tissue engineering. Different nanoparticles localized to spatially distinct locations within a single implant allowed two different tissue types to develop in controllable areas of an implant. As a consequence of this, we predict that complex tissues and organs can be engineered by the in situ development of multiple cell types guided by spatially restricted nanoparticles. PMID:20808289

Experimental tumor growth of canine osteosarcoma cell line on chick embryo chorioallantoic membrane (in vivo studies).

PubMed

Walewska, Magdalena; Dolka, Izabella; Małek, Anna; Wojtalewicz, Anna; Wojtkowska, Agata; Żbikowski, Artur; Lechowski, Roman; Zabielska-Koczywąs, Katarzyna

2017-05-12

The chick embryo chorioallantoic membrane (CAM) model is extensively used in human medicine in preclinical oncological studies. The CAM model has several advantages: low cost, simple experimental approach, time saving and following "3R principles". Research has shown that the human osteosarcoma cell lines U2OS, MMNG-HOS, and SAOS can form tumors on the CAM. In veterinary medicine, this has been described only for feline fibrosarcomas, feline mammary carcinomas and canine osteosarcomas. However, in case of canine osteosarcomas, it has been shown that only non-adherent osteosarcoma stem cells isolated from KTOSA5 and CSKOS cell lines have the ability to form microtumors on the CAM after an incubation period of 5 days, in contrast to adherent KTOSA5 and CSKOS cells. In the presented study, we have proven that the commercial adherent canine osteosarcoma cell line (D-17) can form vascularized tumors on the CAM after the incubation period of 10 days.

Dynamic mechanical measurement of the viscoelasticity of single adherent cells

NASA Astrophysics Data System (ADS)

Corbin, Elise A.; Adeniba, Olaoluwa O.; Ewoldt, Randy H.; Bashir, Rashid

2016-02-01

Many recent studies on the viscoelasticity of individual cells link mechanics with cellular function and health. Here, we introduce a measurement of the viscoelastic properties of individual human colon cancer cells (HT-29) using silicon pedestal microelectromechanical systems (MEMS) resonant sensors. We demonstrate that the viscoelastic properties of single adherent cells can be extracted by measuring a difference in vibrational amplitude of our resonant sensor platform. The magnitude of vibration of the pedestal sensor is measured using a laser Doppler vibrometer (LDV). A change in amplitude of the sensor, compared with the driving amplitude (amplitude ratio), is influenced by the mechanical properties of the adhered cells. The amplitude ratio of the fixed cells was greater than the live cells, with a p-value <0.0001. By combining the amplitude shift with the resonant frequency shift measure, we determined the elastic modulus and viscosity values of 100 Pa and 0.0031 Pa s, respectively. Our method using the change in amplitude of resonant MEMS devices can enable the determination of a refined solution space and could improve measuring the stiffness of cells.

High throughput RNAi assay optimization using adherent cell cytometry.

PubMed

Nabzdyk, Christoph S; Chun, Maggie; Pradhan, Leena; Logerfo, Frank W

2011-04-25

siRNA technology is a promising tool for gene therapy of vascular disease. Due to the multitude of reagents and cell types, RNAi experiment optimization can be time-consuming. In this study adherent cell cytometry was used to rapidly optimize siRNA transfection in human aortic vascular smooth muscle cells (AoSMC). AoSMC were seeded at a density of 3000-8000 cells/well of a 96 well plate. 24 hours later AoSMC were transfected with either non-targeting unlabeled siRNA (50 nM), or non-targeting labeled siRNA, siGLO Red (5 or 50 nM) using no transfection reagent, HiPerfect or Lipofectamine RNAiMax. For counting cells, Hoechst nuclei stain or Cell Tracker green were used. For data analysis an adherent cell cytometer, Celigo® was used. Data was normalized to the transfection reagent alone group and expressed as red pixel count/cell. After 24 hours, none of the transfection conditions led to cell loss. Red fluorescence counts were normalized to the AoSMC count. RNAiMax was more potent compared to HiPerfect or no transfection reagent at 5 nM siGLO Red (4.12 +/-1.04 vs. 0.70 +/-0.26 vs. 0.15 +/-0.13 red pixel/cell) and 50 nM siGLO Red (6.49 +/-1.81 vs. 2.52 +/-0.67 vs. 0.34 +/-0.19). Fluorescence expression results supported gene knockdown achieved by using MARCKS targeting siRNA in AoSMCs. This study underscores that RNAi delivery depends heavily on the choice of delivery method. Adherent cell cytometry can be used as a high throughput-screening tool for the optimization of RNAi assays. This technology can accelerate in vitro cell assays and thus save costs.

High throughput RNAi assay optimization using adherent cell cytometry

PubMed Central

2011-01-01

Background siRNA technology is a promising tool for gene therapy of vascular disease. Due to the multitude of reagents and cell types, RNAi experiment optimization can be time-consuming. In this study adherent cell cytometry was used to rapidly optimize siRNA transfection in human aortic vascular smooth muscle cells (AoSMC). Methods AoSMC were seeded at a density of 3000-8000 cells/well of a 96well plate. 24 hours later AoSMC were transfected with either non-targeting unlabeled siRNA (50 nM), or non-targeting labeled siRNA, siGLO Red (5 or 50 nM) using no transfection reagent, HiPerfect or Lipofectamine RNAiMax. For counting cells, Hoechst nuclei stain or Cell Tracker green were used. For data analysis an adherent cell cytometer, Celigo® was used. Data was normalized to the transfection reagent alone group and expressed as red pixel count/cell. Results After 24 hours, none of the transfection conditions led to cell loss. Red fluorescence counts were normalized to the AoSMC count. RNAiMax was more potent compared to HiPerfect or no transfection reagent at 5 nM siGLO Red (4.12 +/-1.04 vs. 0.70 +/-0.26 vs. 0.15 +/-0.13 red pixel/cell) and 50 nM siGLO Red (6.49 +/-1.81 vs. 2.52 +/-0.67 vs. 0.34 +/-0.19). Fluorescence expression results supported gene knockdown achieved by using MARCKS targeting siRNA in AoSMCs. Conclusion This study underscores that RNAi delivery depends heavily on the choice of delivery method. Adherent cell cytometry can be used as a high throughput-screening tool for the optimization of RNAi assays. This technology can accelerate in vitro cell assays and thus save costs. PMID:21518450

Human Antibodies to PhtD, PcpA, and Ply Reduce Adherence to Human Lung Epithelial Cells and Murine Nasopharyngeal Colonization by Streptococcus pneumoniae

PubMed Central

Kaur, Ravinder; Surendran, Naveen; Ochs, Martina

2014-01-01

Streptococcus pneumoniae adherence to human epithelial cells (HECs) is the first step in pathogenesis leading to infections. We sought to determine the role of human antibodies against S. pneumoniae protein vaccine candidates PhtD, PcpA, and Ply in preventing adherence to lung HECs in vitro and mouse nasopharyngeal (NP) colonization in vivo. Human anti-PhtD, -PcpA, and -Ply antibodies were purified and Fab fragments generated. Fabs were used to test inhibition of adherence of TIGR4 and nonencapsulated strain RX1 to A549 lung HECs. The roles of individual proteins in adherence were tested using isogenic mutants of strain TIGR4. Anti-PhtD, -PcpA, and -Ply human antibodies were assessed for their ability to inhibit NP colonization in vivo by passive transfer of human antibody in a murine model. Human antibodies generated against PhtD and PcpA caused a decrease in adherence to A549 cells (P < 0.05). Anti-PhtD but not anti-PcpA antibodies showed a protective role against mouse NP colonization. To our surprise, anti-Ply antibodies also caused a significant (P < 0.05) reduction in S. pneumoniae colonization. Our results support the potential of PhtD, PcpA, and Ply protein vaccine candidates as alternatives to conjugate vaccines to prevent non-serotype-specific S. pneumoniae colonization and invasive infection. PMID:25245804

Galectin-1 induces cell adhesion to the extracellular matrix and apoptosis of non-adherent human colon cancer Colo201 cells.

PubMed

Horiguchi, Natsuko; Arimoto, Kei-ichiro; Mizutani, Atsushi; Endo-Ichikawa, Yoko; Nakada, Hiroshi; Taketani, Shigeru

2003-12-01

To isolate cDNAs for molecules involved in cell adhesion to the extracellular matrix, expression cloning with non-adherent colon cancer Colo201 cells was carried out. Four positive clones were isolated and, when sequenced, one was found to be galectin-1, a beta-galactoside-binding protein. When cultured on fibronectin-, laminin-, and collagen-coated and non-coated dishes, the adherent galectin-1 cDNA-transfected Colo201 cells increased and spread somewhat. Immunofluorescence staining revealed that galectin-1 was expressed inside and outside of Colo201 cells. The adhesion was dependent on the carbohydrate-recognition domain of galectin-1 since lactose inhibited the adhesion and exogenously-added galectin-1 caused the adhesion. PD58059, an inhibitor of mitogen-activated protein kinase, or LY294002, a phosphoinositide 3-OH kinase inhibitor, decreased the adhesion. Furthermore, the expression of galectin-1 in Colo201 cells induced apoptotic cell death, while exogenously-added galectin-1 did not cause apoptosis. These results indicate that galectin-1 plays a role in both cell-matrix interactions and the inhibition of Colo201 cell proliferation, and suggest that galectin-1 expressed in cells could be associated with apoptosis.

Biodegradable charged polyester-based vectors (BCPVs) as an efficient non-viral transfection nanoagent for gene knockdown of the BCR-ABL hybrid oncogene in a human chronic myeloid leukemia cell line

NASA Astrophysics Data System (ADS)

Yang, Chengbin; Panwar, Nishtha; Wang, Yucheng; Zhang, Butian; Liu, Maixian; Toh, Huiting; Yoon, Ho Sup; Tjin, Swee Chuan; Chong, Peter Han Joo; Law, Wing-Cheung; Chen, Chih-Kuang; Yong, Ken-Tye

2016-04-01

First-line therapy of chronic myelogenous leukemia (CML) has always involved the use of BCR-ABL tyrosine-kinase inhibitors which is associated with an abnormal chromosome called Philadelphia chromosome. Although the overall survival rate has been improved by the current therapeutic regime, the presence of resistance has resulted in limited efficacy. In this study, an RNA interference (RNAi)-based therapeutic regime is proposed with the aim to knockdown the BCR-ABL hybrid oncogene using small interfering RNA (siRNA). The siRNA transfection rates have usually been limited due to the declining contact probability among polyplexes and the non-adherent nature of leukemic cells. Our work aims at addressing this limitation by using a biodegradable charged polyester-based vector (BCPV) as a nanocarrier for the delivery of BCR-ABL-specific siRNA to the suspension culture of a K562 CML cell line. BCR-ABL siRNAs were encapsulated in the BCPVs by electrostatic force. Cell internalization was facilitated by the BCPV and assessed by confocal microscopy and flow cytometry. The regulation of the BCR-ABL level in K562 cells as a result of RNAi was analyzed by real-time polymerase chain reaction (RT-PCR). We observed that BCPV was able to form stable nanoplexes with siRNA molecules, even in the presence of fetal bovine serum (FBS), and successfully assisted in vitro siRNA transfection in the non-adherent K562 cells. As a consequence of downregulation of BCR-ABL, BCPV-siRNA nanoplexes inhibited cell proliferation and promoted cell apoptosis. All results were compared with a commercial transfection reagent, Lipofectamine2000™, which served as a positive control. More importantly, this class of non-viral vector exhibits biodegradable features and negligible cytotoxicity, thus providing a versatile platform to deliver siRNA to non-adherent leukemia cells with high transfection efficiency by effectively overcoming extra- and intra-cellular barriers. Due to the excellent in vitro transfection results from BCPV-siRNA, a newly developed biodegradable transfection agent, BCPV, is being probed for transfection performance in an animal model.

The OPTIMIZE trial: Rationale and design of a randomized controlled trial of motivational enhancement therapy to improve adherence to statin medication.

PubMed

Rash, Joshua A; Lavoie, Kim L; Sigal, Ronald J; Campbell, David J T; Manns, Braden J; Tonelli, Marcello; Campbell, Tavis S

2016-07-01

Statins are a class of medications that are particularly effective for lowering cholesterol and reducing cardiovascular morbidity and mortality. Despite a range of benefits, non-adherence to statin medication is prevalent with 50% to 75% of patients failing to adhere to treatment within the first 2-years. A previous review on interventions to improve adherence to cholesterol lowering medication concluded that rigorous trials were needed with emphasis on the patient's perspective and shared decision making. Motivational interviewing (MInt) is a promising patient-centered approach for improving adherence in patients with chronic diseases. This manuscript describes the rational and design of a randomized controlled trial (RCT) testing the efficacy of MInt in improving adherence to statin medication. Patients filling their first statin prescription will be recruited to complete a 6-month observation run-in period (phase-1) after which medication possession ratio (MPR) will be assessed. Patients meeting criteria for non-adherence (MPR≤60%) will be invited to participate in the trial. 336 non-adherent new statin users will undergo a fasting lipid panel, complete baseline questionnaires, and be randomly allocated to receive four sessions of adherence education delivered using MInt (EdMInt) or to an education control (EC) delivered at 3-month intervals. Final assessments will occur 12-months after the first EdMInt or EC session. The primary outcome is change in MPR adherence to statin medication from baseline to 12-months. Secondary outcomes include within-patient change in self-reported medication adherence, stage of change and self-efficacy for medication adherence, motivation to adhere to statin medication, and lipid profile. Copyright © 2016 Elsevier Inc. All rights reserved.

Predictors of short- and long-term adherence with a Mediterranean-type diet intervention: the PREDIMED randomized trial.

PubMed

Downer, Mary Kathryn; Gea, Alfredo; Stampfer, Meir; Sánchez-Tainta, Ana; Corella, Dolores; Salas-Salvadó, Jordi; Ros, Emilio; Estruch, Ramón; Fitó, Montserrat; Gómez-Gracia, Enrique; Arós, Fernando; Fiol, Miquel; De-la-Corte, Francisco Jose Garcia; Serra-Majem, Lluís; Pinto, Xavier; Basora, Josep; Sorlí, José V; Vinyoles, Ernest; Zazpe, Itziar; Martínez-González, Miguel-Ángel

2016-06-14

Dietary intervention success requires strong participant adherence, but very few studies have examined factors related to both short-term and long-term adherence. A better understanding of predictors of adherence is necessary to improve the design and execution of dietary intervention trials. This study was designed to identify participant characteristics at baseline and study features that predict short-term and long-term adherence with interventions promoting the Mediterranean-type diet (MedDiet) in the PREvención con DIeta MEDiterránea (PREDIMED) randomized trial. Analyses included men and women living in Spain aged 55-80 at high risk for cardiovascular disease. Participants were randomized to the MedDiet supplemented with either complementary extra-virgin olive oil (EVOO) or tree nuts. The control group and participants with insufficient information on adherence were excluded. PREDIMED began in 2003 and ended in 2010. Investigators assessed covariates at baseline and dietary information was updated yearly throughout follow-up. Adherence was measured with a validated 14-point Mediterranean-type diet adherence score. Logistic regression was used to examine associations between baseline characteristics and adherence at one and four years of follow-up. Participants were randomized to the MedDiet supplemented with EVOO (n = 2,543; 1,962 after exclusions) or tree nuts (n = 2,454; 2,236 after exclusions). A higher number of cardiovascular risk factors, larger waist circumference, lower physical activity levels, lower total energy intake, poorer baseline adherence to the 14-point adherence score, and allocation to MedDiet + EVOO each independently predicted poorer adherence. Participants from PREDIMED recruiting centers with a higher total workload (measured as total number of persons-years of follow-up) achieved better adherence. No adverse events or side effects were reported. To maximize dietary adherence in dietary interventions, additional efforts to promote adherence should be used for participants with lower baseline adherence to the intended diet and poorer health status. The design of multicenter nutrition trials should prioritize few large centers with more participants in each, rather than many small centers. This study was registered at controlled-trials.com (http://www.controlled-trials. com/ISRCTN35739639). International Standard Randomized Controlled Trial Number (ISRCTN): 35739639. Registration date: 5 October 2005. parallel randomized trial.

Contribution of Spores to the Ability of Clostridium difficile To Adhere to Surfaces

PubMed Central

Joshi, Lovleen Tina; Phillips, Daniel S.; Williams, Catrin F.; Alyousef, Abdullah

2012-01-01

Clostridium difficile is the commonest cause of hospital-acquired infection in the United Kingdom. We characterized the abilities of 21 clinical isolates to form spores; to adhere to inorganic and organic surfaces, including stainless steel and human adenocarcinoma cells; and to germinate. The composition of culture media had a significant effect on spore formation, as significantly more spores were produced in brain heart infusion broth (Student's t test; P = 0.018). The spore surface relative hydrophobicity (RH) varied markedly (14 to 77%) and was correlated with the ability to adhere to stainless steel. We observed no correlation between the ribotype and the ability to adhere to steel. When the binding of hydrophobic (DS1813; ribotype 027; RH, 77%) and hydrophilic (DS1748; ribotype 002; RH, 14%) spores to human gut epithelial cells at different stages of cell development was examined, DS1813 spores adhered more strongly, suggesting the presence of surface properties that aid attachment to human cells. Electron microscopy studies revealed the presence of an exosporium surrounding DS1813 spores that was absent from spores of DS1748. Finally, the ability of spores to germinate was found to be strain and medium dependent. While the significance of these findings to the disease process has yet to be determined, this study has highlighted the importance of analyzing multiple isolates when attempting to characterize the behavior of a bacterial species. PMID:22923404

Strain-specific inhibition of the adherence of uropathogenic bacteria to bladder cells by probiotic Lactobacillus spp.

PubMed

de Llano, Dolores González; Arroyo, Amalia; Cárdenas, Nivia; Rodríguez, Juan Miguel; Moreno-Arribas, M Victoria; Bartolomé, Begoña

2017-06-01

Urinary tract infections (UTIs), one of most common infections worldwide, face high recurrence rates and increasing antimicrobial resistance. Probiotic bacteria, especially of the genus Lactobacillus, are considered a promising preventive and/or treatment therapy against UTIs. In order to elucidate the mechanisms involved in these beneficial effects, we studied the impact of different Lactobacillus strains (Lactobacillus salivarius UCM572, L. plantarum CLC17 and L. acidophilus 01) in the adherence of reference and clinical uropathogenic strains (Escherichia coli ATCC® 53503, E. coli 10791, Enterococcus faecalis 04-1, En. faecalis 08-1 and Staphylococcus epidermidis 08-3) to T24 epithelial bladder cells. In general, the Lactobacillus strains with previous in vivo evidence of beneficial effects against UTIs (L. salivarius UCM572 and L. acidophilus 01) significantly inhibited the adherence of the five uropathogens to T24 cells, displaying percentages of inhibition ranging between 22.2% and 43.9%, and between 16.5% and 53.7%, respectively. On the other hand, L. plantarum CLC17, a strain with no expected effects on UTIs, showed almost negligible anti-adherence effects.Therefore, these in vitro results suggest that inhibition of the adherence of uropathogens to epithelial bladder cells may be one of the mechanisms involved in the potential beneficial effects of probiotics against UTIs in vivo. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Adhesion-Dependent Redistribution of MAP Kinase and MEK Promotes Muscarinic Receptor-Mediated Signaling to the Nucleus

PubMed Central

Slack, Barbara E.; Siniaia, Marina S.

2008-01-01

The mitogen-activated protein kinases (MAPKs) are activated by extracellular signals, and translocate to the nucleus where they modulate transcription. Integrin-mediated cell adhesion to extracellular matrix (ECM) proteins is required for efficient transmission of MAPK-based signals initiated by growth factors. However, the modulation of G protein-coupled receptor (GPCR) signaling by adhesion is less well understood. In the present study we assessed the impact of cell adhesion on MAPK activation by muscarinic M3 receptors. The muscarinic agonist carbachol more efficiently promoted stress fiber formation and tyrosine phosphorylation of focal adhesion-associated proteins in M3 receptor-expressing cells adherent to fibronectin or collagen type I, as compared to polylysine. Overall MAPK activation was robust in cells adherent to all three substrata. However, total levels of MAPK and mitogen-activated protein kinase kinase (MEK) in the nucleus were significantly greater in cells adherent to ECM proteins for 2.5 hours, and levels of activated MAPK and MEK in the nuclei of these cells were higher following carbachol stimulation, relative to levels in cells adherent to polylysine. MEK inhibitors did not prevent adhesion-dependent translocation of MAPK and MEK to the nucleus, and increased nuclear phospho-MEK levels in carbachol-stimulated cells. The results suggest that adhesion of cells to ECM triggers the redistribution of MAPK and MEK to the nucleus, possibly as a result of the cytoskeletal rearrangements that accompany cell spreading. This may represent a mechanism for priming the nucleus with MEK and MAPK, leading to more rapid and pronounced increases in intranuclear phospho-MAPK upon GPCR stimulation. PMID:15779001

The effect of financial incentives on adherence to antipsychotic depot medication: does it change over time?

PubMed

Pavlickova, Hana; Bremner, Stephen A; Priebe, Stefan

2015-08-01

A recent cluster-randomized controlled trial found that offering financial incentives improves adherence to long-acting injectable antipsychotics (LAIs). The present study investigates whether the impact of incentives diminishes over time and whether the improvement in adherence is linked to the amount of incentives offered. Seventy-three teams with 141 patients with psychotic disorders (using ICD-10) were randomized to the intervention or control group. Over 1 year, patients in the intervention group received £15 (US $23) for each LAI, while control patients received treatment as usual. Adherence levels, ie, the percentage of prescribed LAIs that were received, were calculated for quarterly intervals. The amount of incentives offered was calculated from the treatment cycle at baseline. Multilevel models were used to examine the time course of the effect of incentives and the effect of the amount of incentives offered on adherence. Adherence increased in both the intervention and the control group over time by an average of 4.2% per quarterly interval (95% CI, 2.8%-5.6%; P < .001). Despite this general increase, adherence in the intervention group remained improved compared to the control group by between 11% and 14% per quarterly interval. There was no interaction effect between time and treatment group. Further, a higher total amount of incentives was associated with poorer adherence (βbootstrapped = -0.11; 95% CIbootstrapped, -0.20 to -0.01; P = .023). A substantial effect of financial incentives on adherence to LAIs occurs within the first 3 months of the intervention and is sustained over 1 year. A higher total amount of incentives does not increase the effect. ISRCTN.com identifier: ISRCTN77769281 and UKCRN.org identifier: 7033. © Copyright 2015 Physicians Postgraduate Press, Inc.

Evaluation of an adherent mouse embryonic stem cell in vitro assay to predict developmental toxicity of ToxCast chemicals.

EPA Science Inventory

The potential for most environmental chemicals to produce developmental toxicity is unknown. Mouse embryonic stem cell (mESC) assays are an alternative in vitro model to assess chemicals. The chemical space evaluated using mESC and compared to in vivo is limited. We used an adher...

Prevention of peridural fibrosis using a cyclooxygenase-2 inhibitor (nonsteroidal anti-inflammatory drug) soaked in absorbable gelatin sponge: an experimental comparative animal model.

PubMed

Sae-Jung, Surachai; Jirarattanaphochai, Kitti

2013-07-15

Experimental study. To evaluate the efficacy and safety of peridural parecoxib-soaked absorbable gelatin sponge, and cellulose membrane on peridural fibrosis prevention in an animal model. Postoperative peridural fibrosis is one of the causes of failed back surgery syndrome. Nonsteroidal anti-inflammatory drugs inhibit the inflammatory response, while an absorbable gelatin sponge or cellulose membrane interposes between the dura and the paraspinal muscle to staunch the surgical bleeding. These mechanisms may prevent peridural fibrosis. Forty L5-L6 laminectomized adult Sprague-Dawley rats were randomly allocated into 4 groups. The high parecoxib group received 6 mg of parecoxib soaked into an absorbable gelatin sponge placed over the dura. The low parecoxib group was given 2 mg of parecoxib soaked into an absorbable gelatin sponge. The dura in the cellulose group was covered with a cellulose membrane, while the control group received normal saline drip before surgical wound closure. All rats were killed at 6 weeks for histopathological assessment. The fibroblast density, inflammatory cell density, fibrous adherence, and adverse events were quantified. The obtained results were analyzed statistically. The respective mean fibroblast density in the high parecoxib, low parecoxib, cellulose, and control groups was 217.77 ± 51.76, 317.51 ± 126.92, 321.80 ± 90.94, and 328.48 ± 73.41 cells/mm², while the respective mean inflammatory cell density was 539.65 ± 236.52, 910.17 ± 242.59, 1011.84 ± 239.30, and 1261.78 ± 319.68 cells/mm². The mean fibroblast and inflammatory cell densities of the high parecoxib group were significantly lower than the control. The high parecoxib group also showed statistically less fibrous adherence than low parecoxib, cellulose, and control groups. The high-dose parecoxib-soaked absorbable gelatin sponge can prevent peridural fibrosis without complications. The low-dose parecoxib and cellulose membrane provided no significant benefit vis-à-vis prevention of peridural fibrosis, as adduced from the lack of any statistically significant difference between the test and control rats.

A Randomized Trial of a Multicomponent Intervention to Promote Medication Adherence: The Teen Adherence in Kidney Transplant Effectiveness of Intervention Trial (TAKE-IT).

PubMed

Foster, Bethany J; Pai, Ahna L H; Zelikovsky, Nataliya; Amaral, Sandra; Bell, Lorraine; Dharnidharka, Vikas R; Hebert, Diane; Holly, Crystal; Knauper, Baerbel; Matsell, Douglas; Phan, Veronique; Rogers, Rachel; Smith, Jodi M; Zhao, Huaqing; Furth, Susan L

2018-07-01

Poor adherence to immunosuppressive medications is a major cause of premature graft loss among children and young adults. Multicomponent interventions have shown promise but have not been fully evaluated. Unblinded parallel-arm randomized trial to assess the efficacy of a clinic-based adherence-promoting intervention. Prevalent kidney transplant recipients 11 to 24 years of age and 3 or more months posttransplantation at 8 kidney transplantation centers in Canada and the United States (February 2012 to May 2016) were included. Adherence was electronically monitored in all participants during a 3-month run-in, followed by a 12-month intervention. Participants assigned to the TAKE-IT intervention could choose to receive text message, e-mail, and/or visual cue dose reminders and met with a coach at 3-month intervals when adherence data from the prior 3 months were reviewed with the participant. "Action-Focused Problem Solving" was used to address adherence barriers selected as important by the participant. Participants assigned to the control group met with coaches at 3-month intervals but received no feedback about adherence data. The primary outcomes were electronically measured "taking" adherence (the proportion of prescribed doses of immunosuppressive medications taken) and "timing" adherence (the proportion of doses of immunosuppressive medications taken between 1 hour before and 2 hours after the prescribed time of administration) on each day of observation. Secondary outcomes included the standard deviation of tacrolimus trough concentrations, self-reported adherence, acute rejection, and graft failure. 81 patients were assigned to intervention (median age, 15.5 years; 57% male) and 88 to the control group (median age, 15.8 years; 61% male). Electronic adherence data were available for 64 intervention and 74 control participants. Participants in the intervention group had significantly greater odds of taking prescribed medications (OR, 1.66; 95% CI, 1.15-2.39) and taking medications at or near the prescribed time (OR, 1.74; 95% CI, 1.21-2.50) than controls. Lack of electronic adherence data for some participants may have introduced bias. There was low statistical power for clinical outcomes. The multicomponent TAKE-IT intervention resulted in significantly better medication adherence than the control condition. Better medication adherence may result in improved graft outcomes, but this will need to be demonstrated in larger studies. Registered at ClinicalTrials.gov with study number NCT01356277. Copyright © 2018 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.

Gastrointestinal cell lines form polarized epithelia with an adherent mucus layer when cultured in semi-wet interfaces with mechanical stimulation.

PubMed

Navabi, Nazanin; McGuckin, Michael A; Lindén, Sara K

2013-01-01

Mucin glycoproteins are secreted in large quantities by mucosal epithelia and cell surface mucins are a prominent feature of the glycocalyx of all mucosal epithelia. Currently, studies investigating the gastrointestinal mucosal barrier use either animal experiments or non-in vivo like cell cultures. Many pathogens cause different pathology in mice compared to humans and the in vitro cell cultures used are suboptimal because they are very different from an in vivo mucosal surface, are often not polarized, lack important components of the glycocalyx, and often lack the mucus layer. Although gastrointestinal cell lines exist that produce mucins or polarize, human cell line models that reproducibly create the combination of a polarized epithelial cell layer, functional tight junctions and an adherent mucus layer have been missing until now. We trialed a range of treatments to induce polarization, 3D-organization, tight junctions, mucin production, mucus secretion, and formation of an adherent mucus layer that can be carried out using standard equipment. These treatments were tested on cell lines of intestinal (Caco-2, LS513, HT29, T84, LS174T, HT29 MTX-P8 and HT29 MTX-E12) and gastric (MKN7, MKN45, AGS, NCI-N87 and its hTERT Clone5 and Clone6) origins using Ussing chamber methodology and (immuno)histology. Semi-wet interface culture in combination with mechanical stimulation and DAPT caused HT29 MTX-P8, HT29 MTX-E12 and LS513 cells to polarize, form functional tight junctions, a three-dimensional architecture resembling colonic crypts, and produce an adherent mucus layer. Caco-2 and T84 cells also polarized, formed functional tight junctions and produced a thin adherent mucus layer after this treatment, but with less consistency. In conclusion, culture methods affect cell lines differently, and testing a matrix of methods vs. cell lines may be important to develop better in vitro models. The methods developed herein create in vitro mucosal surfaces suitable for studies of host-pathogen interactions at the mucosal surface.

Gastrointestinal Cell Lines Form Polarized Epithelia with an Adherent Mucus Layer when Cultured in Semi-Wet Interfaces with Mechanical Stimulation

PubMed Central

Navabi, Nazanin; McGuckin, Michael A.; Lindén, Sara K.

2013-01-01

Mucin glycoproteins are secreted in large quantities by mucosal epithelia and cell surface mucins are a prominent feature of the glycocalyx of all mucosal epithelia. Currently, studies investigating the gastrointestinal mucosal barrier use either animal experiments or non-in vivo like cell cultures. Many pathogens cause different pathology in mice compared to humans and the in vitro cell cultures used are suboptimal because they are very different from an in vivo mucosal surface, are often not polarized, lack important components of the glycocalyx, and often lack the mucus layer. Although gastrointestinal cell lines exist that produce mucins or polarize, human cell line models that reproducibly create the combination of a polarized epithelial cell layer, functional tight junctions and an adherent mucus layer have been missing until now. We trialed a range of treatments to induce polarization, 3D-organization, tight junctions, mucin production, mucus secretion, and formation of an adherent mucus layer that can be carried out using standard equipment. These treatments were tested on cell lines of intestinal (Caco-2, LS513, HT29, T84, LS174T, HT29 MTX-P8 and HT29 MTX-E12) and gastric (MKN7, MKN45, AGS, NCI-N87 and its hTERT Clone5 and Clone6) origins using Ussing chamber methodology and (immuno)histology. Semi-wet interface culture in combination with mechanical stimulation and DAPT caused HT29 MTX-P8, HT29 MTX-E12 and LS513 cells to polarize, form functional tight junctions, a three-dimensional architecture resembling colonic crypts, and produce an adherent mucus layer. Caco-2 and T84 cells also polarized, formed functional tight junctions and produced a thin adherent mucus layer after this treatment, but with less consistency. In conclusion, culture methods affect cell lines differently, and testing a matrix of methods vs. cell lines may be important to develop better in vitro models. The methods developed herein create in vitro mucosal surfaces suitable for studies of host-pathogen interactions at the mucosal surface. PMID:23869232

Microplate Fluorescence Assay for Measurement of the Ability of Strains of Listeria monocytogenes from Meat and Meat-Processing Plants To Adhere to Abiotic Surfaces▿

PubMed Central

Gamble, Rachel; Muriana, Peter M.

2007-01-01

Listeria monocytogenes is a significant food-borne pathogen that is capable of adhering to and producing biofilms on processing equipment, making it difficult to eliminate from meat-processing environments and allowing potential contamination of ready-to-eat (RTE) products. We devised a fluorescence-based microplate method for screening isolates of L. monocytogenes for the ability to adhere to abiotic surfaces. Strains of L. monocytogenes were incubated for 2 days at 30°C in 96-well microplates, and the plates were washed in a plate washer. The retained cells were incubated for 15 min at 25°C with 5,6-carboxyfluorescein diacetate and washed again, and then the fluorescence was read with a plate reader. Several enzymatic treatments (protease, lipase, and cellulase) were effective in releasing adherent cells from the microplates, and this process was used for quantitation on microbiological media. Strongly adherent strains of L. monocytogenes were identified that had 15,000-fold-higher levels of fluorescence and 100,000-fold-higher plate counts in attachment assays than weakly adherent strains. Strongly adherent strains of L. monocytogenes adhered equally well to four different substrates (glass, plastic, rubber, and stainless steel); showed high-level attachment on microplates at 10, 20, 30, and 40°C; and showed significant differences from weakly adherent strains when examined by scanning electron microscopy. A greater incidence of strong adherence was observed for strains isolated from RTE meats than for those isolated from environmental surfaces. Analysis of surface adherence among Listeria isolates from processing environments may provide a better understanding of the molecular mechanisms involved in attachment and suggest solutions to eliminate them from food-processing environments. PMID:17586676

Design and development of microbioreactors for long-term cell culture in controlled oxygen microenvironments.

PubMed

Abaci, Hasan E; Devendra, Raghavendra; Smith, Quinton; Gerecht, Sharon; Drazer, German

2012-02-01

The ability to control the oxygen level to which cells are exposed in tissue culture experiments is crucial for many applications. Here, we design, develop and test a microbioreactor (MBR) for long-term cell culture studies with the capability to accurately control and continuously monitor the dissolved oxygen (DO) level in the cell microenvironment. In addition, the DO level can be controlled independently from other cues, such as the viscous shear-stress acting on the cells. We first analyze the transport of oxygen in the proposed device and determine the materials and dimensions that are compatible with uniform oxygen tension and low shear-stress at the cell level. The device is also designed to culture a statistically significant number of cells. We use fully transparent materials and the overall design of the device is compatible with live-cell imaging. The proposed system includes real-time read-out of actual DO levels, is simple to fabricate at low cost, and can be easily expanded to control the concentration of other microenvironmental solutes. We performed control experiments in the absence of cells to demonstrate that the MBR can be used to accurately modulate DO levels ranging from atmospheric level to 1%, both under no flow and perfusion conditions. We also demonstrate cancer cell attachment and viability within the MBR. The proposed MBR offers the unprecedented capability to perform on-line measurement and analysis of DO levels in the microenvironment of adherent cultures and to correlate them with various cellular responses.

The Absence of N-Acetyl-D-glucosamine Causes Attenuation of Virulence of Candida albicans upon Interaction with Vaginal Epithelial Cells In Vitro

PubMed Central

Manczinger, Máté; Bocsik, Alexandra; Kocsis, Gabriella F.; Vörös, Andrea; Hegedűs, Zoltán; Marton, Annamária; Vízler, Csaba; Tubak, Vilmos; Deli, Mária; Kemény, Lajos; Nagy, István; Lakatos, Lóránt

2015-01-01

To better understand the molecular events underlying vulvovaginal candidiasis, we established an in vitro system. Immortalized vaginal epithelial cells were infected with live, yeast form C. albicans and C. albicans cultured in the same medium without vaginal epithelial cells were used as control. In both cases a yeast to hyphae transition was robustly induced. Whole transcriptome sequencing was used to identify specific gene expression changes in C. albicans. Numerous genes leading to a yeast to hyphae transition and hyphae specific genes were upregulated in the control hyphae and the hyphae in response to vaginal epithelial cells. Strikingly, the GlcNAc pathway was exclusively triggered by vaginal epithelial cells. Functional analysis in our in vitro system revealed that the GlcNAc biosynthesis is involved in the adherence to, and the ability to kill, vaginal epithelial cells in vitro, thus indicating the key role for this pathway in the virulence of C. albicans upon vulvovaginal candidiasis. PMID:26366412

Non-viral gene delivery regulated by stiffness of cell adhesion substrates.

PubMed

Kong, Hyun Joon; Liu, Jodi; Riddle, Kathryn; Matsumoto, Takuya; Leach, Kent; Mooney, David J

2005-06-01

Non-viral gene vectors are commonly used for gene therapy owing to safety concerns with viral vectors. However, non-viral vectors are plagued by low levels of gene transfection and cellular expression. Current efforts to improve the efficiency of non-viral gene delivery are focused on manipulations of the delivery vector, whereas the influence of the cellular environment in DNA uptake is often ignored. The mechanical properties (for example, rigidity) of the substrate to which a cell adheres have been found to mediate many aspects of cell function including proliferation, migration and differentiation, and this suggests that the mechanics of the adhesion substrate may regulate a cell's ability to uptake exogeneous signalling molecules. In this report, we present a critical role for the rigidity of the cell adhesion substrate on the level of gene transfer and expression. The mechanism relates to material control over cell proliferation, and was investigated using a fluorescent resonance energy transfer (FRET) technique. This study provides a new material-based control point for non-viral gene therapy.

Severe asthma and adherence to peak flow monitoring: longitudinal assessment of psychological aspects.

PubMed

Halimi, Laurence; Pry, René; Pithon, Gérard; Godard, Philippe; Varrin, Muriel; Chanez, Pascal

2010-10-01

Adherence in severe asthma is a difficult health problem. Although psychosocial factors may be responsible for non-adherence, few longitudinal studies have investigated their link with adherence, with most studies having focused on pharmacology. Sixty patients with severe asthma were recruited. Adherence was electronically monitored using peak flow measurements at entry and after 1 year of follow-up. Eysenck's Personality Inventory, Rotter's Locus of Control (LOC), and health control beliefs were all studied. Multiple logistic regression (MLR) was used for risk calculations. Initially, subjects with poor adherence had an external LOC (P=.001) and a high extraversion score (P=.003) compared to those with good adherence. The lie score was high in all patients. Nocturnal awakenings were highly significantly correlated with poor adherence (P=.006). After 1 year, patient adherence, extraversion, and neuroticism remained unchanged. The LOC changed in subjects with poor adherence, showing a less "external" orientation (P=.007). The health parameters were better at the end of the study. By MLR analysis, externality, extraversion, and low social desirability were associated with poor adherence. Patients with poor adherence had a greater probability of nocturnal symptoms. No specific personality type was associated with lack of adherence in the present study, but a high extraversion score, a low social desirability score, and a high level of externality were all predictors of poor adherence. Copyright 2010 Elsevier Inc. All rights reserved.

Complement Regulator Factor H Mediates a Two-step Uptake of Streptococcus pneumoniae by Human Cells*

PubMed Central

Agarwal, Vaibhav; Asmat, Tauseef M.; Luo, Shanshan; Jensch, Inga; Zipfel, Peter F.; Hammerschmidt, Sven

2010-01-01

Streptococcus pneumoniae, a human pathogen, recruits complement regulator factor H to its bacterial cell surface. The bacterial PspC protein binds Factor H via short consensus repeats (SCR) 8–11 and SCR19–20. In this study, we define how bacterially bound Factor H promotes pneumococcal adherence to and uptake by epithelial cells or human polymorphonuclear leukocytes (PMNs) via a two-step process. First, pneumococcal adherence to epithelial cells was significantly reduced by heparin and dermatan sulfate. However, none of the glycosaminoglycans affected binding of Factor H to pneumococci. Adherence of pneumococci to human epithelial cells was inhibited by monoclonal antibodies recognizing SCR19–20 of Factor H suggesting that the C-terminal glycosaminoglycan-binding region of Factor H mediates the contact between pneumococci and human cells. Blocking of the integrin CR3 receptor, i.e. CD11b and CD18, of PMNs or CR3-expressing epithelial cells reduced significantly the interaction of pneumococci with both cell types. Similarly, an additional CR3 ligand, Pra1, derived from Candida albicans, blocked the interaction of pneumococci with PMNs. Strikingly, Pra1 inhibited also pneumococcal uptake by lung epithelial cells but not adherence. In addition, invasion of Factor H-coated pneumococci required the dynamics of host-cell actin microfilaments and was affected by inhibitors of protein-tyrosine kinases and phosphatidylinositol 3-kinase. In conclusion, pneumococcal entry into host cells via Factor H is based on a two-step mechanism. The first and initial contact of Factor H-coated pneumococci is mediated by glycosaminoglycans expressed on the surface of human cells, and the second step, pneumococcal uptake, is integrin-mediated and depends on host signaling molecules such as phosphatidylinositol 3-kinase. PMID:20504767

Effect of six different peri-implantitis disinfection methods on in vivo human oral biofilm.

PubMed

Gosau, Martin; Hahnel, Sebastian; Schwarz, Frank; Gerlach, Till; Reichert, Torsten E; Bürgers, Ralf

2010-08-01

The aim of this human in vivo pilot study was to evaluate the efficacy of six antimicrobial agents on the surface decontamination of an oral biofilm attached to titanium implants. For in vivo biofilm formation, we fixed titanium specimens to individual removable acrylic upper jaw splints (14 specimens in every splint), which were worn by four volunteers overnight for 12 h. The specimens were then treated with different antimicrobial agents for 1 min (Sodium hypochlorite, Hydrogen peroxide 3%, Chlorhexidingluconate 0.2%, Plax, Listerine, citric acid 40%). Afterwards, we quantified the total bacterial load and the viability of adhering bacteria by live or dead cell labelling in combination with fluorescence microscopy. The total bacterial load on the titanium surfaces was significantly higher after incubation in the control solution phosphate-buffered saline (PBS) than after disinfection in sodium hypochlorite, hydrogen peroxide, chlorhexidine, Plax, Listerine, and citric acid. Furthermore, a significantly lower ratio between dead and total adhering bacteria (bactericidal effect) was found after incubation in control PBS, Plax mouth rinse, and citric acid than after incubation in sodium hypochlorite, hydrogen peroxide, chlorhexidine, and Listerine. All tested antiseptics seem to be able to reduce the total amount of microorganisms accumulating on titanium surfaces. Furthermore, sodium hypochlorite, hydrogen peroxide, chlorhexidine, and Listerine showed a significant bactericidal effect against adhering bacteria.

A MULTI-CENTER CLUSTER-RANDOMIZED TRIAL OF A MULTI-FACTORIAL INTERVENTION TO IMPROVE ANTIHYPERTENSIVE MEDICATION ADHERENCE AND BLOOD PRESSURE CONTROL AMONG PATIENTS AT HIGH CARDIOVASCULAR RISK (The COM99 study)*

PubMed Central

Pladevall, Manel; Brotons, Carlos; Gabriel, Rafael; Arnau, Anna; Suarez, Carmen; de la Figuera, Mariano; Marquez, Emilio; Coca, Antonio; Sobrino, Javier; Divine, George; Heisler, Michele; Williams, L Keoki

2010-01-01

Background Medication non-adherence is common and results in preventable disease complications. This study assesses the effectiveness of a multifactorial intervention to improve both medication adherence and blood pressure control and to reduce cardiovascular events. Methods and Results In this multi-center, cluster-randomized trial, physicians from hospital-based hypertension clinics and primary care centers across Spain were randomized to receive and provide the intervention to their high-risk patients. Eligible patients were ≥50 years of age, had uncontrolled hypertension, and had an estimated 10-year cardiovascular risk greater than 30%. Physicians randomized to the intervention group counted patients’ pills, designated a family member to support adherence behavior, and provided educational information to patients. The primary outcome was blood pressure control at 6 months. Secondary outcomes included both medication adherence and a composite end-point of all cause mortality and cardiovascular-related hospitalizations. Seventy-nine physicians and 877 patients participated in the trial. The mean duration of follow-up was 39 months. Intervention patients were less likely to have an uncontrolled systolic blood pressure (odds ratio 0.62; 95% confidence interval [CI] 0.50–0.78) and were more likely to be adherent (OR 1.91; 95% CI 1.19–3.05) when compared with control group patients at 6 months. After five years 16% of the patients in the intervention group and 19% in the control group met the composite end-point (hazard ratio 0.97; 95% CI 0.67–1.39). Conclusions A multifactorial intervention to improve adherence to antihypertensive medication was effective in improving both adherence and blood pressure control, but it did not appear to improve long-term cardiovascular events. PMID:20823391

Radiation sensitivity of Merkel cell carcinoma cell lines

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

Leonard, J.H.; Ramsay, J.R.; Birrell, G.W.

1995-07-30

Merkel cell carcinoma (MCC), being a small cell carcinoma, would be expected to be sensitive to radiation. Clinical analysis of patients at our center, especially those with macroscopic disease, would suggest the response is quite variable. We have recently established a number of MCC cell lines from patients prior to radiotherapy, and for the first time are in a position to determine their sensitivity under controlled conditions. Some of the MCC lines grew as suspension cultures and could not be single cell cloned; therefore, it was not possible to use clonogenic survival for all cell lines. A tetrazolium based (MTT)more » assay was used for these lines, to estimate cell growth after {gamma} irradiation. Control experiments were conducted on lymphoblastoid cell lines (LCL) and the adherent MCC line, MCC13, to demonstrate that the two assays were comparable under the conditions used. We have examined cell lines from MCC, small cell lung cancer (SCLC), malignant melanomas, Epstein Barr virus (EBV) transformed lymphocytes (LCL), and skin fibroblasts for their sensitivity to {gamma} irradiation using both clonogenic cell survival and MTT assays. The results show that the tumor cell lines have a range of sensitivities, with melanoma being more resistant (surviving fraction at 2 Gy (SF2) 0.57 and 0.56) than the small cell carcinoma lines, MCC (SF2 range 0.21-0.45, mean SF2 0.30, n = 8) and SCLC (SF2 0.31). Fibroblasts were the most sensitive (SF2 0.13-0.20, mean 0.16, n = 5). The MTT assay, when compared to clonogenic assay for the MCC13 adherent line and the LCL, gave comparable results under the conditions used. Both assays gave a range of SF2 values for the MCC cell lines, suggesting that these cancers would give a heterogeneous response in vivo. The results with the two derivative clones of MCC14 (SF2 for MCC14/1 0.38, MCC14/2 0.45) would further suggest that some of them may develop resistance during clonogenic evolution. 25 refs., 3 figs., 1 tab.« less

Medication adherence in randomized controlled trials evaluating cardiovascular or mortality outcomes in dialysis patients: A systematic review.

PubMed

Murali, Karumathil M; Mullan, Judy; Chen, Jenny H C; Roodenrys, Steven; Lonergan, Maureen

2017-01-31

Medication non-adherence is common among renal dialysis patients. High degrees of non-adherence in randomized controlled trials (RCTs) can lead to failure to detect a true treatment effect. Cardio-protective pharmacological interventions have shown no consistent benefit in RCTs involving dialysis patients. Whether non-adherence contributes to this lack of efficacy is unknown. We aimed to investigate how medication adherence and drug discontinuation were assessed, reported and addressed in RCTs, evaluating cardiovascular or mortality outcomes in dialysis patients. Electronic database searches were performed in MEDLINE, EMBASE & Cochrane CENTRAL for RCTs published between 2005-2015, evaluating self-administered medications, in adult dialysis patients, which reported clinical cardiovascular or mortality endpoints, as primary or secondary outcomes. Study characteristics, outcomes, methods of measuring and reporting adherence, and data on study drug discontinuation were analyzed. Of the 642 RCTs in dialysis patients, 22 trials (12 placebo controlled), which included 19,322 patients, were eligible. The trialed pharmacological interventions included anti-hypertensives, phosphate binders, lipid-lowering therapy, cardio-vascular medications, homocysteine lowering therapy, fish oil and calcimimetics. Medication adherence was reported in five trials with a mean of 81% (range: 65-92%) in the intervention arm and 84.5% (range: 82-87%) in the control arm. All the trials that reported adherence yielded negative study outcomes for the intervention. Study-drug discontinuation was reported in 21 trials (mean 33.2%; 95% CI, 22.0 to 44.5, in intervention and 28.8%; 95% CI, 16.8 to 40.8, in control). Trials with more than 20% study drug discontinuation, more often yielded negative study outcomes (p = 0.018). Non-adherence was included as a contributor to drug discontinuation in some studies, but the causes of discontinuation were not reported consistently between studies, and non-adherence was listed under different categories, thereby potentiating the misclassification of adherence. Reporting of medication adherence and study-drug discontinuation in RCTs investigating cardiovascular or mortality endpoints in dialysis patients are inconsistent, making it difficult to compare studies and evaluate their impact on outcomes. Recommendations for consistent reporting of non-adherence and causes of drug discontinuation in RCTs will therefore help to assess their impact on clinical outcomes.

Neurosphere and adherent culture conditions are equivalent for malignant glioma stem cell lines.

PubMed

Rahman, Maryam; Reyner, Karina; Deleyrolle, Loic; Millette, Sebastien; Azari, Hassan; Day, Bryan W; Stringer, Brett W; Boyd, Andrew W; Johns, Terrance G; Blot, Vincent; Duggal, Rohit; Reynolds, Brent A

2015-03-01

Certain limitations of the neurosphere assay (NSA) have resulted in a search for alternative culture techniques for brain tumor-initiating cells (TICs). Recently, reports have described growing glioblastoma (GBM) TICs as a monolayer using laminin. We performed a side-by-side analysis of the NSA and laminin (adherent) culture conditions to compare the growth and expansion of GBM TICs. GBM cells were grown using the NSA and adherent culture conditions. Comparisons were made using growth in culture, apoptosis assays, protein expression, limiting dilution clonal frequency assay, genetic affymetrix analysis, and tumorigenicity in vivo. In vitro expansion curves for the NSA and adherent culture conditions were virtually identical (P=0.24) and the clonogenic frequencies (5.2% for NSA vs. 5.0% for laminin, P=0.9) were similar as well. Likewise, markers of differentiation (glial fibrillary acidic protein and beta tubulin III) and proliferation (Ki67 and MCM2) revealed no statistical difference between the sphere and attachment methods. Several different methods were used to determine the numbers of dead or dying cells (trypan blue, DiIC, caspase-3, and annexin V) with none of the assays noting a meaningful variance between the two methods. In addition, genetic expression analysis with microarrays revealed no significant differences between the two groups. Finally, glioma cells derived from both methods of expansion formed large invasive tumors exhibiting GBM features when implanted in immune-compromised animals. A detailed functional, protein and genetic characterization of human GBM cells cultured in serum-free defined conditions demonstrated no statistically meaningful differences when grown using sphere (NSA) or adherent conditions. Hence, both methods are functionally equivalent and remain suitable options for expanding primary high-grade gliomas in tissue culture.

Neurosphere and adherent culture conditions are equivalent for malignant glioma stem cell lines

PubMed Central

Reyner, Karina; Deleyrolle, Loic; Millette, Sebastien; Azari, Hassan; Day, Bryan W.; Stringer, Brett W.; Boyd, Andrew W.; Johns, Terrance G.; Blot, Vincent; Duggal, Rohit; Reynolds, Brent A.

2015-01-01

Certain limitations of the neurosphere assay (NSA) have resulted in a search for alternative culture techniques for brain tumor-initiating cells (TICs). Recently, reports have described growing glioblastoma (GBM) TICs as a monolayer using laminin. We performed a side-by-side analysis of the NSA and laminin (adherent) culture conditions to compare the growth and expansion of GBM TICs. GBM cells were grown using the NSA and adherent culture conditions. Comparisons were made using growth in culture, apoptosis assays, protein expression, limiting dilution clonal frequency assay, genetic affymetrix analysis, and tumorigenicity in vivo. In vitro expansion curves for the NSA and adherent culture conditions were virtually identical (P=0.24) and the clonogenic frequencies (5.2% for NSA vs. 5.0% for laminin, P=0.9) were similar as well. Likewise, markers of differentiation (glial fibrillary acidic protein and beta tubulin III) and proliferation (Ki67 and MCM2) revealed no statistical difference between the sphere and attachment methods. Several different methods were used to determine the numbers of dead or dying cells (trypan blue, DiIC, caspase-3, and annexin V) with none of the assays noting a meaningful variance between the two methods. In addition, genetic expression analysis with microarrays revealed no significant differences between the two groups. Finally, glioma cells derived from both methods of expansion formed large invasive tumors exhibiting GBM features when implanted in immune-compromised animals. A detailed functional, protein and genetic characterization of human GBM cells cultured in serum-free defined conditions demonstrated no statistically meaningful differences when grown using sphere (NSA) or adherent conditions. Hence, both methods are functionally equivalent and remain suitable options for expanding primary high-grade gliomas in tissue culture. PMID:25806119

Cost-Effectiveness of Financial Incentives to Promote Adherence to Depot Antipsychotic Medication: Economic Evaluation of a Cluster-Randomised Controlled Trial

PubMed Central

Henderson, Catherine; Knapp, Martin; Yeeles, Ksenija; Bremner, Stephen; Eldridge, Sandra; David, Anthony S.; O’Connell, Nicola; Burns, Tom; Priebe, Stefan

2015-01-01

Background Offering a modest financial incentive to people with psychosis can promote adherence to depot antipsychotic medication, but the cost-effectiveness of this approach has not been examined. Methods Economic evaluation within a pragmatic cluster-randomised controlled trial. 141 patients under the care of 73 teams (clusters) were randomised to intervention or control; 138 patients with diagnoses of schizophrenia, schizo-affective disorder or bipolar disorder participated. Intervention participants received £15 per depot injection over 12 months, additional to usual acute, mental and community primary health services. The control group received usual health services. Main outcome measures: incremental cost per 20% increase in adherence to depot antipsychotic medication; incremental cost of ‘good’ adherence (defined as taking at least 95% of the prescribed number of depot medications over the intervention period). Findings Economic and outcome data for baseline and 12-month follow-up were available for 117 participants. The adjusted difference in adherence between groups was 12.2% (73.4% control vs. 85.6% intervention); the adjusted costs difference was £598 (95% CI -£4 533, £5 730). The extra cost per patient to increase adherence to depot medications by 20% was £982 (95% CI -£8 020, £14 000). The extra cost per patient of achieving 'good' adherence was £2 950 (CI -£19 400, £27 800). Probability of cost-effectiveness exceeded 97.5% at willingness-to-pay values of £14 000 for a 20% increase in adherence and £27 800 for good adherence. Interpretation Offering a modest financial incentive to people with psychosis is cost-effective in promoting adherence to depot antipsychotic medication. Direct healthcare costs (including costs of the financial incentive) are unlikely to be increased by this intervention. Trial Registration ISRCTN.com 77769281 PMID:26448540

Does adherence monitoring reduce controlled substance abuse in chronic pain patients?

PubMed

Manchikanti, Laxmaiah; Manchukonda, Rajeev; Damron, Kim S; Brandon, Doris; McManus, Carla D; Cash, Kim

2006-01-01

Opioids are used extensively for chronic pain management in the United States. The frequency of opioid use prior to presenting to interventional pain management settings and in interventional pain management settings has been shown to be above 90%. Given that controlled substance abuse and illicit drug use are prevalent phenomena, adherence monitoring of patients that are prescribed opioids is becoming common. Adherence monitoring is carried out by an appropriate history, periodic evaluation of appropriate intake of drugs, random drug testing, and pill counts. Crucial to adherence monitoring is an initial controlled substance agreement and repeated review of the terms of this agreement with on-going education. However, the effect of adherence monitoring on drug abuse is unclear. To identify controlled substance abuse through implementation of the terms of a controlled substance agreement, including periodic review and monitoring outside the organization. Prospective evaluation with historical controls. Five hundred consecutive patients receiving prescription controlled substances were followed in a prospective manner. The evaluation consisted of a chart review to monitor controlled substance intake, with special attention to drugs obtained from outside the organization. Data collection for this purpose included information from records, pharmacies, referring physicians, and all the physicians involved in the treatment of the patient. Results from 500 consecutive patients were evaluated. Controlled substance abuse was seen in 9% of patients; overall, 5% of patients were obtaining controlled substances from other physicians, and 4% from illegal sources. Adherence monitoring, including controlled substance agreements and various periodic measures of compliance was associated with a 50% reduction in opioid abuse.

Candida glabrata's Genome Plasticity Confers a Unique Pattern of Expressed Cell Wall Proteins.

PubMed

López-Fuentes, Eunice; Gutiérrez-Escobedo, Guadalupe; Timmermans, Bea; Van Dijck, Patrick; De Las Peñas, Alejandro; Castaño, Irene

2018-06-05

Candida glabrata is the second most common cause of candidemia, and its ability to adhere to different host cell types, to microorganisms, and to medical devices are important virulence factors. Here, we consider three characteristics that confer extraordinary advantages to C. glabrata within the host. (1) C. glabrata has a large number of genes encoding for adhesins most of which are localized at subtelomeric regions. The number and sequence of these genes varies substantially depending on the strain, indicating that C. glabrata can tolerate high genomic plasticity; (2) The largest family of CWPs (cell wall proteins) is the EPA (epithelial adhesin) family of adhesins. Epa1 is the major adhesin and mediates adherence to epithelial, endothelial and immune cells. Several layers of regulation like subtelomeric silencing, cis- acting regulatory regions, activators, nutritional signaling, and stress conditions tightly regulate the expression of many adhesin-encoding genes in C. glabrata , while many others are not expressed. Importantly, there is a connection between acquired resistance to xenobiotics and increased adherence; (3) Other subfamilies of adhesins mediate adherence to Candida albicans , allowing C. glabrata to efficiently invade the oral epithelium and form robust biofilms. It is noteworthy that every C. glabrata strain analyzed presents a unique pattern of CWPs at the cell surface.

Insertional inactivation of Eap in Staphylococcus aureus strain Newman confers reduced staphylococcal binding to fibroblasts.

PubMed

Hussain, Muzaffar; Haggar, Axana; Heilmann, Christine; Peters, Georg; Flock, Jan-Ingmar; Herrmann, Mathias

2002-06-01

To initiate invasive infection, Staphylococcus aureus must adhere to host substrates, such as the extracellular matrix or eukaryotic cells, by virtue of different surface proteins (adhesins). Recently, we identified a 60-kDa cell-secreted extracellular adherence protein (Eap) of S. aureus strain Newman with broad-spectrum binding characteristics (M. Palma, A. Haggar, and J. I. Flock, J. Bacteriol. 181:2840-2845, 1999), and we have molecularly confirmed Eap to be an analogue of the previously identified major histocompatibility complex class II analog protein (Map) (M. Hussain, K. Becker, C. von Eiff, G. Peter, and M. Herrmann, Clin. Diagn. Lab. Immunol. 8:1281-1286, 2001). Previous analyses of the Eap/Map function performed with purified protein did not allow dissection of its precise role in the complex situation of the staphylococcal whole cell presenting several secreted and wall-bound adhesins. Therefore, the role of Eap was investigated by constructing a stable eap::ermB deletion in strain Newman and by complementation of the mutant. Patterns of extracted cell surface proteins analyzed both by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by Western ligand assays with various adhesive matrix molecules clearly confirmed the absence of Eap in the mutant. However, binding and adhesion tests using whole staphylococcal cells demonstrated that both the parent and mutant strains bound equally well to fibronectin- and fibrinogen-coated surfaces, possibly due to their recognition by other staphylococcal adhesins. Furthermore, Eap mediated staphylococcal agglutination of both wild-type and mutant cells. In contrast, the mutant adhered to a significantly lesser extent to cultured fibroblasts (P < 0.001) than did the wild type, while adherence was restorable upon complementation. Furthermore, adherence to both epithelial cells (P < 0.05) and fibroblasts (not significant) could be blocked with antibodies against Eap, whereas preimmune serum was not active. In conclusion, Eap may contribute to pathogenicity by promoting adhesion of whole staphylococcal cells to complex eukaryotic substrates.

Medication-Taking Practices of Patients on Antiretroviral HIV Therapy: Control, Power, and Intentionality

PubMed Central

Panter, Abigail T.; Mouw, Mary S.; Amola, Kemi; Stein, Kathryn E.; Murphy, Joseph S.; Maiese, Eric M.; Wohl, David A.

2015-01-01

Abstract Among people living with HIV (PLWH), adherence to antiretroviral therapy (ART) is crucial for health, but patients face numerous challenges achieving sustained lifetime adherence. We conducted six focus groups with 56 PLWH regarding ART adherence barriers and collected sociodemographics and ART histories. Participants were recruited through clinics and AIDS service organizations in North Carolina. Dedoose software was used to support thematic analysis. Participants were 59% male, 77% black, aged 23–67 years, and living with HIV 4–20 years. Discussions reflected the fluid, complex nature of ART adherence. Maintaining adherence required participants to indefinitely assert consistent control across multiple areas including: their HIV disease, their own bodies, health care providers, and social systems (e.g., criminal justice, hospitals, drug assistance programs). Participants described limited control over treatment options, ART's impact on their body, and inconsistent access to ART and subsequent inability to take ART as prescribed. When participants felt they had more decision-making power, intentionally choosing whether and how to take ART was not exclusively a decision about best treating HIV. Instead, through these decisions, participants tried to regain some amount of power and control in their lives. Supportive provider relationships assuaged these struggles, while perceived side-effects and multiple co-morbidities further complicated adherence. Adherence interventions need to better convey adherence as a continuous, changing process, not a fixed state. A perspective shift among care providers could also help address negative consequences of the perceived power struggles and pressures that may drive patients to exert control via intentional medication taking practices. PMID:26505969

Medication-Taking Practices of Patients on Antiretroviral HIV Therapy: Control, Power, and Intentionality.

PubMed

Muessig, Kathryn E; Panter, Abigail T; Mouw, Mary S; Amola, Kemi; Stein, Kathryn E; Murphy, Joseph S; Maiese, Eric M; Wohl, David A

2015-11-01

Among people living with HIV (PLWH), adherence to antiretroviral therapy (ART) is crucial for health, but patients face numerous challenges achieving sustained lifetime adherence. We conducted six focus groups with 56 PLWH regarding ART adherence barriers and collected sociodemographics and ART histories. Participants were recruited through clinics and AIDS service organizations in North Carolina. Dedoose software was used to support thematic analysis. Participants were 59% male, 77% black, aged 23-67 years, and living with HIV 4-20 years. Discussions reflected the fluid, complex nature of ART adherence. Maintaining adherence required participants to indefinitely assert consistent control across multiple areas including: their HIV disease, their own bodies, health care providers, and social systems (e.g., criminal justice, hospitals, drug assistance programs). Participants described limited control over treatment options, ART's impact on their body, and inconsistent access to ART and subsequent inability to take ART as prescribed. When participants felt they had more decision-making power, intentionally choosing whether and how to take ART was not exclusively a decision about best treating HIV. Instead, through these decisions, participants tried to regain some amount of power and control in their lives. Supportive provider relationships assuaged these struggles, while perceived side-effects and multiple co-morbidities further complicated adherence. Adherence interventions need to better convey adherence as a continuous, changing process, not a fixed state. A perspective shift among care providers could also help address negative consequences of the perceived power struggles and pressures that may drive patients to exert control via intentional medication taking practices.

Characterization of an immortalized human vaginal epithelial cell line.

PubMed

Rajan, N; Pruden, D L; Kaznari, H; Cao, Q; Anderson, B E; Duncan, J L; Schaeffer, A J

2000-02-01

Adherence of type 1 piliated Escherichia coli to vaginal mucosa plays a major role in the pathogenesis of ascending urinary tract infections (UTIs) in women. Progress in understanding the mechanism of adherence to the vaginal surface could be enhanced by the utilization of well-characterized vaginal epithelial cells. The objective of this study was to immortalize vaginal epithelial cells and study their bacterial adherence properties. Primary vaginal cells were obtained from a normal post-menopausal woman, immortalized by infection with E6/E7 genes from human papillomavirus 16 (HPV 16) and cultured in serum free keratinocyte growth factor medium. Positive immunostaining with a pool of antibodies to cytokeratins 1, 5, 10 and 14 (K1, K5, K10 and K14) and to K13 confirmed the epithelial origin of these cells. The immortalized cells showed binding of type 1 piliated E. coli in a pili specific and mannose sensitive manner. This model system should facilitate studies on the interaction of pathogens with vaginal mucosal cells, an essential step in the progression of ascending UTIs in women.

Evidence for the replication of bovine leukemia virus in the B lymphocytes

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

Paul, P.S.; Pomeroy, K.A.; Johnson, D.W.

1977-06-01

Bovine peripheral blood lymphocytes from a cow with persistent lymphocytosis were separated on nylon wool columns into nylon-adherent and nonadherent populations. Nylon-adherent cells were highly enriched for surface immunoglobulin (SIg) bearing B lymphocytes (95.5%) and nonadherent cells for SIg negative non-B cells, presumably T lymphocytes (96.3%). The B lymphocytes were found to be the major producers for bovine leukemia virus. A total of 39% of the B-enriched cells, surviving after 72 hours in culture, produced bovine leukemia virus as compared with 0.5% of the non-B cells.

Effect of 2,4-Dichlorophenoxyacetic acid herbicide Escherichia coli growth, chemical, composition, and cellular envelope

USGS Publications Warehouse

Carr, R.S.; Biedenbach, J.M.; Hooten, R.L.

2001-01-01

2,4-Dichlorophenoxyacetic acid (2,4-D) is a herbicide widely used in the world and mainly excreted by the renal route in exposed humans and animals. Herbicides can affect other nontarget organisms, such as Escherichia coli. We observed that a single exposure to 1 mM 2,4-D diminished growth and total protein content in all E. coli strains tested in vitro. In addition, successive exposures to 0.01 mM 2,4-D had a toxic effect decreasing growth up to early stationary phase. Uropathogenic E. coli adhere to epithelial cells mediated by fimbriae, adhesins, and hydrophobic properties. 2,4-D exposure of uropathogenic E. coli demonstrated altered hydrophobicity and fimbriation. Hydrophobicity index values obtained by partition in p-xylene/water were 300-420% higher in exposed cells than in control ones. Furthermore, values of hemagglutination titer, protein contents in fimbrial crude extract, and electron microscopy demonstrated a significant diminution of fimbriation in treated cells. Other envelope alterations could be detected, such as lipoperoxidation, evidenced by decreased polyunsaturated fatty acids and increased lipid degradation products (malonaldehyde), and motility diminution. These alterations decreased cell adherence to erythrocytes, indicating a diminished pathogenic capacity of the 2,4-D-exposed E. coli. ?? 2001 by John Wiley & Sons, Inc.

Modeling of the interaction between osteoblasts and biocompatible substrates as a function of adhesion strength.

PubMed

Portan, D V; Deligianni, D D; Deligianni, K; Kroustalli, A A; Tyllianakis, M; Papanicolaou, G C

2018-03-01

A goal of current implantology research is to design devices that induce controlled, guided, and rapid healing. Nanoscale structured substrates [e.g., titania nanotubes (TNTs) or carbon nanotubes (CNTs)] dramatically improve the functions of conventional biomaterials. The present investigation evaluated the behavior of osteoblasts cells cultured on smooth and nanostructured substrates, by measuring osteoblasts specific biomarkers [alkaline phosphatase (AP) and total protein] and cells adhesion strength to substrates, followed by semi-empirical modeling to predict the experimental results. Findings were in total agreement with the current state of the art. The proliferation, as well as the AP and total protein levels were higher on the nanostructure phases (TNTs, CNTs) comparing to the smooth ones (plastic and pure titanium). Cells adhesion strength measured was found higher on the nanostructured materials. This coincided with a higher value of proteins which are directly implicated in the process of adherence. Results were accurately predicted through the Viscoelastic Hybrid Interphase Model. A gradual adherence of bone cells to implants using multilayered biomaterials that involve biodegradable polymeric films and a nanoscale modification of titanium surface is suggested to improve performance through an interphase-mediated osteointegration of orthopedic implants. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 621-628, 2018. © 2017 Wiley Periodicals, Inc.

Important factors for cell-membrane permeabilization by gold nanoparticles activated by nanosecond-laser irradiation

PubMed Central

Yao, Cuiping; Rudnitzki, Florian; Hüttmann, Gereon; Zhang, Zhenxi; Rahmanzadeh, Ramtin

2017-01-01

Purpose Pulsed-laser irradiation of light-absorbing gold nanoparticles (AuNPs) attached to cells transiently increases cell membrane permeability for targeted molecule delivery. Here, we targeted EGFR on the ovarian carcinoma cell line OVCAR-3 with AuNPs. In order to optimize membrane permeability and to demonstrate molecule delivery into adherent OVCAR-3 cells, we systematically investigated different experimental conditions. Materials and methods AuNPs (30 nm) were functionalized by conjugation of the antibody cetuximab against EGFR. Selective binding of the particles was demonstrated by silver staining, multiphoton imaging, and fluorescence-lifetime imaging. After laser irradiation, membrane permeability of OVCAR-3 cells was studied under different conditions of AuNP concentration, cell-incubation medium, and cell–AuNP incubation time. Membrane permeability and cell viability were evaluated by flow cytometry, measuring propidium iodide and fluorescein isothiocyanate–dextran uptake. Results Adherently growing OVCAR-3 cells can be effectively targeted with EGFR-AuNP. Laser irradiation led to successful permeabilization, and 150 kDa dextran was successfully delivered into cells with about 70% efficiency. Conclusion Antibody-targeted and laser-irradiated AuNPs can be used to deliver molecules into adherent cells. Efficacy depends not only on laser parameters but also on AuNP:cell ratio, cell-incubation medium, and cell–AuNP incubation time. PMID:28848345

Integrated thin film cadmium sulfide solar cell module

NASA Technical Reports Server (NTRS)

Mickelsen, R. A.; Abbott, D. D.

1971-01-01

The design, development, fabrication and tests of flexible integrated thin-film cadmium sulfide solar cells and modules are discussed. The development of low cost and high production rate methods for interconnecting cells into large solar arrays is described. Chromium thin films were applied extensively in the deposited cell structures as a means to: (1) achieve high adherence between the cadmium sulfide films and the vacuum-metallized copper substrates, (2) obtain an ohmic contact to the cadmium sulfide films, and (3) improve the adherence of gold films as grids or contact areas.

Osteoblast-secreted WISP-1 promotes adherence of prostate cancer cells to bone via the VCAM-1/integrin α4β1 system.

PubMed

Chang, An-Chen; Chen, Po-Chun; Lin, Yu-Feng; Su, Chen-Ming; Liu, Ju-Fang; Lin, Tien-Huang; Chuang, Show-Mei; Tang, Chih-Hsin

2018-07-10

Bone metastasis is a frequent occurrence in prostate cancer (PCa) that is associated with severe complications such as fracture, bone pain and hypercalcemia. The cross-talk between metastatic cancer cells and bone is critical to the development and progression of bone metastases. In our previous data, we have described how the involvement of the Wnt-induced secreted protein-1/vascular cell adhesion molecule-1 (WISP-1/VCAM-1) system in this tumor-bone interaction contributes to human PCa cell motility. In this study, we found that WISP-1 regulates bone mineralization by inducing bone morphogenetic protein-2 (BMP2), BMP4 and osteopontin (OPN) expression in osteoblasts. We also found that WISP-1 inhibited RANKL-dependent osteoclastogenesis. Moreover, osteoblast-derived WISP-1 enhanced VCAM-1 expression in PCa cells and subsequently promoted the adherence of cancer cells to osteoblasts. Furthermore, endothelin-1 (ET-1) expression in PCa cells was regulated by osteoblast-derived WISP-1, which promoted integrin α4β1 expression in osteoblasts via the MAPK pathway. Pretreatment of PCa cells with VCAM-1 antibody or osteoblasts with integrin α4β1 antibody attenuated the adherence of PCa cells to osteoblasts, suggesting that integrin α4β1 serves as a ligand that captures VCAM-1 + metastatic tumor cells adhering to osteoblasts. Our findings reveal that osteoblast-derived WISP-1 plays a key role in regulating the adhesion of PCa cells to osteoblasts via the VCAM-1/integrin α4β1 system. Osteoblast-derived WISP-1 is a promising target for the prevention and inhibition of PCa-bone interaction. Copyright © 2018 Elsevier B.V. All rights reserved.

Temperature-induced labelling of Fluo-3 AM selectively yields brighter nucleus in adherent cells

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

Meng, Guixian; Pan, Leiting, E-mail: plt@nankai.edu.cn; Li, Cunbo

2014-01-17

Highlights: •We detailedly examine temperature effects of Fluo-3 AM labelling in adherent cells. •4 °C Loading and 20 °C de-esterification of Fluo-3 AM yields brighter nuclei. •Brighter nuclei labelling by Fluo-3 AM also depends on cell adhesion quality. •A qualitative model of the brighter nucleus is proposed. -- Abstract: Fluo-3 is widely used to study cell calcium. Two traditional approaches: (1) direct injection and (2) Fluo-3 acetoxymethyl ester (AM) loading, often bring conflicting results in cytoplasmic calcium ([Ca{sup 2+}]{sub c}) and nuclear calcium ([Ca{sup 2+}]{sub n}) imaging. AM loading usually yields a darker nucleus than in cytoplasm, while direct injectionmore » always induces a brighter nucleus which is more responsive to [Ca{sup 2+}]{sub n} detection. In this work, we detailedly investigated the effects of loading and de-esterification temperatures on the fluorescence intensity of Fluo-3 in response to [Ca{sup 2+}]{sub n} and [Ca{sup 2+}]{sub c} in adherent cells, including osteoblast, HeLa and BV2 cells. Interestingly, it showed that fluorescence intensity of nucleus in osteoblast cells was about two times larger than that of cytoplasm when cells were loaded with Fluo-3 AM at 4 °C and allowed a subsequent step for de-esterification at 20 °C. Brighter nuclei were also acquired in HeLa and BV2 cells using the same experimental condition. Furthermore, loading time and adhesion quality of cells had effect on fluorescence intensity. Taken together, cold loading and room temperature de-esterification treatment of Fluo-3 AM selectively yielded brighter nucleus in adherent cells.« less

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

Ben-Dov, Nadav; Korenstein, Rafi, E-mail: korens@post.tau.ac.il

Recently it has been shown that elevating proton concentration at the cell surface stimulates the formation of membrane invaginations and vesicles accompanied by an enhanced uptake of macromolecules. While the initial induction of inward membrane curvature was rationalized in terms of proton-based increase of charge asymmetry across the membrane, the mechanisms underlying vesicle formation and its scission are still unknown. In light of the critical role of actin in vesicle formation during endocytosis, the present study addresses the involvement of cytoskeletal actin in proton-induced uptake (PIU). The uptake of dextran-FITC is used as a measure for the factual fraction ofmore » inward invaginations that undergo scission from the cell's plasma membrane. Our findings show that the rate of PIU in suspended cells is constant, whereas the rate of PIU in adherent cells is gradually increased in time, saturating at the level possessed by suspended cells. This is consistent with pH induced gradual degradation of stress-fibers in adherent cells. Wortmannin and calyculin-A are able to elevate PIU by 25% in adherent cells but not in suspended cells, while cytochalasin-D, rapamycin and latrunculin-A elevate PIU both in adherent and suspended cells. However, extensive actin depolymerization by high concentrations of latrunculin-A is able to inhibit PIU. We conclude that proton-induced membrane vesiculation is restricted by the actin structural resistance to the plasma membrane bending. Nevertheless, a certain degree of cortical actin restructuring is required for the completion of the scission process. - Highlights: ► Acidification of cells' exterior enhances uptake of macromolecules by the cells. ► Disruption of actin stress fibers leads to enhancement of proton induced uptake. ► Extensive depolymerization of cellular actin attenuates proton-induced uptake.« less

Association of health literacy and medication self-efficacy with medication adherence and diabetes control.

PubMed

Huang, Yen-Ming; Shiyanbola, Olayinka O; Smith, Paul D

2018-01-01

The exact pathway linking health literacy, self-efficacy, medication adherence, and glycemic control for type 2 diabetes remains unclear. Understanding the relationship between patient factors, medication adherence, and lower glycated hemoglobin (HbA1c) may help patients better manage their disease. This study examined the association of health literacy and medication self-efficacy with self-reported diabetes medication adherence, and the association of health literacy, medication self-efficacy, and self-reported diabetes medication adherence with HbA1c of patients with type 2 diabetes. This cross-sectional study utilized a face-to-face questionnaire at two family medicine clinics in a Midwestern state among 174 patients; subjects enrolled were at least 20 years old with diagnosed type 2 diabetes, prescribed at least one oral diabetes medicine, and understood English. Questionnaires were administered to assess the participants': health literacy, using the Newest Vital Sign six-item questionnaire (NVS); self-efficacy for medication use, using the 13-item Self-Efficacy for Appropriate Medication Use Scale; and self-report medication adherence, using the eight-item Morisky Medication Adherence Scale. HbA1c values were obtained from participants' electronic medical records. Multiple linear regressions were used to explore the association of health literacy and medication self-efficacy with both medication adherence and HbA1c level after controlling for all other covariates. Self-reported health status (β = 0.17, p = 0.015) and medication self-efficacy (β = 0.53, p < 0.001) were positively associated with diabetes medication adherence. Health literacy was neither associated with diabetes medication adherence (β = -0.04, p = 0.586) nor HbA1c (β = -0.06, p = 0.542). Lower diabetes medication adherence (β = -0.26, p = 0.008) and higher number of prescribed medications (β = 0.28, p = 0.009) were correlated with higher HbA1c. Health literacy, as measured by the NVS, does not correlate with medication adherence or glycemic control among patients with type 2 diabetes. Interventions to improve patients' self-efficacy of medication use may improve diabetes medication adherence.

Association of health literacy and medication self-efficacy with medication adherence and diabetes control

PubMed Central

Huang, Yen-Ming; Shiyanbola, Olayinka O; Smith, Paul D

2018-01-01

Introduction The exact pathway linking health literacy, self-efficacy, medication adherence, and glycemic control for type 2 diabetes remains unclear. Understanding the relationship between patient factors, medication adherence, and lower glycated hemoglobin (HbA1c) may help patients better manage their disease. This study examined the association of health literacy and medication self-efficacy with self-reported diabetes medication adherence, and the association of health literacy, medication self-efficacy, and self-reported diabetes medication adherence with HbA1c of patients with type 2 diabetes. Methods This cross-sectional study utilized a face-to-face questionnaire at two family medicine clinics in a Midwestern state among 174 patients; subjects enrolled were at least 20 years old with diagnosed type 2 diabetes, prescribed at least one oral diabetes medicine, and understood English. Questionnaires were administered to assess the participants’: health literacy, using the Newest Vital Sign six-item questionnaire (NVS); self-efficacy for medication use, using the 13-item Self-Efficacy for Appropriate Medication Use Scale; and self-report medication adherence, using the eight-item Morisky Medication Adherence Scale. HbA1c values were obtained from participants’ electronic medical records. Multiple linear regressions were used to explore the association of health literacy and medication self-efficacy with both medication adherence and HbA1c level after controlling for all other covariates. Results Self-reported health status (β = 0.17, p = 0.015) and medication self-efficacy (β = 0.53, p < 0.001) were positively associated with diabetes medication adherence. Health literacy was neither associated with diabetes medication adherence (β = −0.04, p = 0.586) nor HbA1c (β = −0.06, p = 0.542). Lower diabetes medication adherence (β = −0.26, p = 0.008) and higher number of prescribed medications (β = 0.28, p = 0.009) were correlated with higher HbA1c. Conclusion Health literacy, as measured by the NVS, does not correlate with medication adherence or glycemic control among patients with type 2 diabetes. Interventions to improve patients’ self-efficacy of medication use may improve diabetes medication adherence. PMID:29785094

Neuroglian-positive plasmatocytes of Manduca sexta and the initiation of hemocyte attachment to foreign surfaces.

PubMed

Nardi, James B; Pilas, Barbara; Bee, Charles Mark; Zhuang, Shufei; Garsha, Karl; Kanost, Michael R

2006-01-01

Observations of hemocyte aggregation on abiotic surfaces suggested that certain plasmatocytes from larvae of Manduca sexta act as foci for hemocyte aggregation. To establish how these particular plasmatocytes form initial attachments to foreign surfaces, they were cultured separately from other selected populations of hemocytes. While all circulating plasmatocytes immunolabel with anti-beta-integrin monoclonal antibody (MAb), only these larger plasmatocytes immunolabel with a MAb to the adhesion protein neuroglian. Neuroglian-negative plasmatocytes and granular cells that have been magnetically segregated from the majority of granular cells adhere to each other but fail to adhere to foreign substrata; by contrast, neuroglian-positive plasmatocytes that segregate with most granular cells adhere firmly to a substratum. Hemocytes form stable aggregates around the large, neuroglian-positive plasmatocytes. However, if neuroglian-positive plasmatocytes are separated from most granular cells, attachment of these plasmatocytes to foreign surfaces is suppressed.

Effects of a mobile phone short message service on antiretroviral treatment adherence in Kenya (WelTel Kenya1): a randomised trial.

PubMed

Lester, Richard T; Ritvo, Paul; Mills, Edward J; Kariri, Antony; Karanja, Sarah; Chung, Michael H; Jack, William; Habyarimana, James; Sadatsafavi, Mohsen; Najafzadeh, Mehdi; Marra, Carlo A; Estambale, Benson; Ngugi, Elizabeth; Ball, T Blake; Thabane, Lehana; Gelmon, Lawrence J; Kimani, Joshua; Ackers, Marta; Plummer, Francis A

2010-11-27

Mobile (cell) phone communication has been suggested as a method to improve delivery of health services. However, data on the effects of mobile health technology on patient outcomes in resource-limited settings are limited. We aimed to assess whether mobile phone communication between health-care workers and patients starting antiretroviral therapy in Kenya improved drug adherence and suppression of plasma HIV-1 RNA load. WelTel Kenya1 was a multisite randomised clinical trial of HIV-infected adults initiating antiretroviral therapy (ART) in three clinics in Kenya. Patients were randomised (1:1) by simple randomisation with a random number generating program to a mobile phone short message service (SMS) intervention or standard care. Patients in the intervention group received weekly SMS messages from a clinic nurse and were required to respond within 48 h. Randomisation, laboratory assays, and analyses were done by investigators masked to treatment allocation; however, study participants and clinic staff were not masked to treatment. Primary outcomes were self-reported ART adherence (>95% of prescribed doses in the past 30 days at both 6 and 12 month follow-up visits) and plasma HIV-1 viral RNA load suppression (<400 copies per mL) at 12 months. The primary analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, NCT00830622. Between May, 2007, and October, 2008, we randomly assigned 538 participants to the SMS intervention (n=273) or to standard care (n=265). Adherence to ART was reported in 168 of 273 patients receiving the SMS intervention compared with 132 of 265 in the control group (relative risk [RR] for non-adherence 0·81, 95% CI 0·69-0·94; p=0·006). Suppressed viral loads were reported in 156 of 273 patients in the SMS group and 128 of 265 in the control group, (RR for virologic failure 0·84, 95% CI 0·71-0·99; p=0·04). The number needed to treat (NNT) to achieve greater than 95% adherence was nine (95% CI 5·0-29·5) and the NNT to achieve viral load suppression was 11 (5·8-227·3). Patients who received SMS support had significantly improved ART adherence and rates of viral suppression compared with the control individuals. Mobile phones might be effective tools to improve patient outcome in resource-limited settings. US President's Emergency Plan for AIDS Relief. Copyright © 2010 Elsevier Ltd. All rights reserved.

Retailer adherence to Family Smoking Prevention and Tobacco Control Act, North Carolina, 2011.

PubMed

Rose, Shyanika W; Myers, Allison E; D'Angelo, Heather; Ribisl, Kurt M

2013-04-04

The Family Smoking Prevention and Tobacco Control Act regulates the sales and marketing of tobacco products in the United States; poor adherence by tobacco retailers may reduce the effectiveness of the Act's provisions. The objectives of this study were 1) to assess whether and to which provisions retailers were adherent and 2) to examine differences in adherence by county, retailer neighborhood, and retailer characteristics. We conducted multivariate analysis of tobacco retailers' adherence to 12 point-of-sale provisions of the Tobacco Control Act in 3 North Carolina counties. We conducted observational audits of 324 retailers during 3 months in 2011 to assess adherence. We used logistic regression to assess associations between adherence to provisions and characteristics of each county, retailer neighborhood, and retailer. We found 15.7% of retailers did not adhere to at least 1 provision; 84.3% adhered to all provisions. The provisions most frequently violated were the ban on sales of cigarettes with modified-risk labels (eg, "light" cigarettes) (43 [13.3%] retailers nonadherent) and the ban on self-service for cigarettes and smokeless tobacco (6 [1.9%] retailers nonadherent). We found significant differences in rates of nonadherence by county and type of retailer. Pharmacies and drug stores were more than 3 times as likely as grocery stores to be nonadherent. Most tobacco retailers have implemented regulatory changes without enforcement by the US Food and Drug Administration. Monitoring rates of adherence by store type and locale (eg, county) may help retailers comply with point-of-sale provisions.

The role of Listeria monocytogenes cell wall surface anchor protein LapB in virulence, adherence, and intracellular replication

USDA-ARS?s Scientific Manuscript database

Lmof2365_2117 is a Listeria monocytogenes putative cell wall surface anchor protein with a conserved domain found in collagen binding proteins. We constructed a deletion mutation in lmof2365_2117 in serotype 4b strain F2365, evaluated its virulence, and determined its ability to adhere and invade co...

Water as foaming agent for open cell polyurethane structures.

PubMed

Haugen, H; Ried, V; Brunner, M; Will, J; Wintermantel, E

2004-04-01

The problem of moisture in polymer processing is known to any polymer engineer, as air bubbles may be formed. Hence granulates are generally dried prior to manufacturing. This study tried to develop a novel processing methods for scaffolds with controlled moisture content in thermoplastic polyurethane. The common foaming agents for polyurethane are organic solvents, whose residues remaining in the scaffold may be harmful to adherent cells, protein growth factors or nearby tissues. Water was used as a foaming agent and NaCl was used as porogens to achieve an open-cell structure. The polyether-polyurethane samples were processed in a heated press, and achieved a porosity of 64%. The pore size ranged between 50 and 500 microm. Human fibroblasts adhered and proliferate in the scaffold. A non-toxic production process was developed to manufacture a porous structure with a thermoplastic polyether-polyurethane. The process enables a mass-production of samples with adjustable pore size and porosity. In contrast to an existing method (solvent casting), the processing of the samples was not limited by its thickness. The process parameters, which attribute mostly to the pore building, were filling volume, temperature, NaCl-concentration and water-uptake rate.

CD44 mediated hyaluronan adhesion of Toxoplasma gondii-infected leukocytes.

PubMed

Hayashi, Takeshi; Unno, Akihiro; Baba, Minami; Ohno, Tamio; Kitoh, Katsuya; Takashima, Yasuhiro

2014-04-01

Toxoplasma gondii is an obligate intracellular apicomplexan parasite that infects humans and animals. Ingested parasites cross the intestinal epithelium, invade leukocytes and are then disseminated to peripheral organs. However, the mechanism of extravasation of the infected leukocytes remains poorly understood. In this study, we demonstrate that T. gondii-invaded human and mouse leukocytes express higher level of CD44, a ligand of hyaluronan (HA), and its expression on myeloid and non-myeloid leukocytes causes T. gondii-invaded human and mouse leukocyte to adhere to HA more effectively than non-invaded leukocytes. The specific adherence of parasite-invaded leukocytes was inhibited by anti CD44 antibody. Leukocytes of CD44 knockout mice did not show parasite-invaded leukocyte specific adhesion. Our results indicate that parasite-invaded leukocytes, regardless of whether myeloid or not, gain higher ability to adhere to HA than non-invaded leukocytes, via upregulation of CD44 expression and/or selective invasion to CD44 highly expressing cells. The difference in ability to adhere to HA between parasite-invaded cells and non-invaded neighboring cells might facilitate effective delivery of parasite-invaded leukocytes to the HA-producing endothelial cell surface and/or HA-rich extra cellular matrix. © 2013.

A cell-ELISA for the quantification of adherent murine macrophages and the surface expression of antigens.

PubMed

Nibbering, P H; Van de Gevel, J S; Van Furth, R

1990-07-20

The present study was performed in order to establish whether a cell-ELISA could be used to determine the expression of antigens by adherent murine peritoneal macrophages and also quantify the numbers of such macrophages. Accurate determination of the number of adherent macrophages proved to be possible with a cell-ELISA designed to assess complement receptor type III (CRIII) expression. Expression of CRIII was considerably more sensitive than determination of the cell-protein or DNA content as a measure of the number of adherent macrophages. For the calculation of the expression of CRIII, Ia antigen, and antigen F4/80 by resident and activated macrophages, use was made of the linear part of the curve obtained when the numbers of macrophages were plotted against the absorbance values for each of the antigens. The values for CRIII expression did not differ significantly between resident macrophages, macrophages activated with recombinant interferon-gamma (rIFN-gamma) and macrophages activated with BCG/PPD. IFN-gamma-activated and BCG/PPD-activated macrophages expressed Ia antigen significantly more intensely than did resident peritoneal macrophages. In contrast the activated macrophages expressed F4/80 significantly less intensely than resident peritoneal macrophages.

Origin-Specific Adhesive Interactions of Mesenchymal Stem Cells with Platelets Influence Their Behavior After Infusion.

PubMed

Sheriff, Lozan; Alanazi, Asma; Ward, Lewis S C; Ward, Carl; Munir, Hafsa; Rayes, Julie; Alassiri, Mohammed; Watson, Steve P; Newsome, Phil N; Rainger, G E; Kalia, Neena; Frampton, Jon; McGettrick, Helen M; Nash, Gerard B

2018-02-28

We investigated the adhesive behavior of mesenchymal stem cells (MSC) in blood, which might influence their fate when infused as therapy. Isolated human bone marrow MSC (BMMSC) or umbilical cord MSC (UCMSC) adhered efficiently from flow to the matrix proteins, collagen, or fibronectin, but did not adhere to endothelial selectins. However, when suspended in blood, BMMSC no longer adhered to collagen, while UCMSC adhered along with many aggregated platelets. Neither MSC adhered to fibronectin from flowing blood, although the fibronectin surface did become coated with a platelet monolayer. UCMSC induced platelet aggregation in platelet rich plasma, and caused a marked drop in platelet count when mixed with whole human or mouse blood in vitro, or when infused into mice. In contrast, BMMSC did not activate platelets or induce changes in platelet count. Interestingly, isolated UCMSC and BMMSC both adhered to predeposited platelets. The differences in behavior in blood were attributable to expression of podoplanin (an activating ligand for the platelet receptor CLEC-2), which was detected on UCMSC, but not BMMSC. Thus, platelets were activated when bound to UCMSC, but not BMMSC. Platelet aggregation by UCMSC was inhibited by recombinant soluble CLEC-2, and UCMSC did not cause a reduction in platelet count when mixed with blood from mice deficient in CLEC-2. We predict that both MSC would carry platelets in the blood, but their interaction with vascular endothelium would depend on podoplanin-induced activation of the bound platelets. Such interactions with platelets might target MSC to damaged tissue, but could also be thrombotic. Stem Cells 2018. © 2018 The Authors STEM CELLS published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

Serotype, hemolysin production, and adherence characteristics of strains of Escherichia coli causing urinary tract infection in dogs.

PubMed

Senior, D F; deMan, P; Svanborg, C

1992-04-01

Virulence factors were studied in 82 strains of Escherichia coli isolated from the urine of dogs with urinary tract infections. The most frequently expressed O antigens were 2, 4, 6, 25, and 22/83. Most strains were K nontypeable. Mannose-sensitive hemagglutination (MSH) with canine erythrocytes was observed in 71 strains and mannose-resistant hemagglutination (MRH) was observed in 32 strains. Strains that caused MSH of erythrocytes from dogs also caused MSH of erythrocytes from guinea pigs. Most strains that caused MRH of human A1P1 erythrocytes also reacted with erythrocytes of dogs. Of 22 strains (27%) that agglutinated human A1P1 erythrocytes, but not A1p erythrocytes, 17 (77%) had specificity for globo A, but did not react with the galactose alpha 1----4galactose beta disaccharide receptor. The remaining 5 strains and 2 others that simultaneously expressed an X adhesin agglutinated galactose alpha 1----4galactose beta-coated latex beads. Bacterial adherence to canine uroepithelial cells from the bladder was most often observed in strains expressing MSH, less often observed in strains expressing MRH, and least often observed in strains that failed to induce hemagglutination. Adherence of MSH strains to canine uroepithelial cells was inhibited by alpha-methyl-D-mannoside. As a group, MRH strains expressing globo-A- and galactose alpha 1----4galactose beta-specific adhesins did not have strong adherence. Strains of E coli isolated from dogs with urinary tract infections most commonly expressed type-1 fimbriae, and the main mechanism of in vitro adherence to canine uroepithelial cells involved a mannose-sensitive mechanism. Overrepresentation of globo-A-specific adhesins did not appear to be related to adherence of canine uroepithelial cells.

Streptococcal adhesin SspA/B analogue peptide inhibits adherence and impacts biofilm formation of Streptococcus mutans

PubMed Central

Ito, Tatsuro; Ichinosawa, Takahiro; Shimizu, Takehiko

2017-01-01

Streptococcus mutans, the major causative agent of dental caries, adheres to tooth surfaces via the host salivary glycoprotein-340 (gp340). This adherence can be competitively inhibited by peptides derived from the SspA/B adhesins of Streptococcus gordonii, a human commensal microbe that competes for the same binding sites. Ssp(A4K-A11K), a double-lysine substituted SspA/B peptide analogue, has been shown to exhibit superior in vitro binding affinity for a gp340-derived peptide (SRCRP2), suggesting that Ssp(A4K-A11K) may be of clinical interest. In the present work, we tested the inhibitory effects of Ssp(A4K-A11K) on adherence and biofilm formation of S. mutans by reconstructing an artificial oral environment using saliva-coated polystyrene plates and hydroxyapatite disks. Bacterial adherence (adherence period: 1 h) was assessed by an enzyme-linked immunosorbent assay using biotinylated bacterial cells. Biofilm formation (periods: 8, 11, or 14 h) was assessed by staining and imaging of the sessile cells, or by recovering biofilm cells and plating for cell counts. The pH values of the culture media were measured as a biofilm acidogenicity indicator. Bactericidality was measured by loss of optical density during culturing in the presence of the peptide. We observed that 650 μM Ssp(A4K-A11K) significantly inhibited adherence of S. mutans to saliva-coated polystyrene; a similar effect was seen on bacterial affinity for SRCRP2. Ssp(A4K-A11K) had lesser effects on the adherence of commensal streptococci. Pretreatment of polystyrene and hydroxyapatite with 650 μM Ssp(A4K-A11K) significantly attenuated biofilm formation, whether tested with glucose- or sucrose-containing media. The SspA/B peptide’s activity did not reflect bactericidality. Strikingly, pH in Ssp-treated 8-h (6.8 ± 0.06) and 11-h (5.5 ± 0.06) biofilms showed higher values than the critical pH. Thus, Ssp(A4K-A11K) acts by inhibiting bacterial adherence and cariogrnic biofilm formation. We further consider these results in the context of the safety, specificity, and stability properties of the Ssp(A4K-A11K) peptide. PMID:28394940

Efficacy and mechanisms of non-antibacterial, chemical plaque control by dentifrices--an in vitro study.

PubMed

Busscher, Henk J; White, Don J; Atema-Smit, Jelly; van der Mei, Henny C

2007-04-01

The provision of antiplaque benefits to dentifrices assists patients in improving hygiene and reducing susceptibility to gingivitis and caries. Chemical plaque control involves different mechanisms and is mostly associated with antibacterial effects, but also includes effects on pellicle surface chemistry to improve cleansing or discourage renewed plaque formation. It is the aim of this paper to analyze in vitro detachment of co-aggregating oral actinomyces and streptococci from pellicle surfaces by dentifrice supernates and to study subsequent de novo streptococcal deposition. Detachment by dentifrices of a co-adhering bacterial pair was studied in the parallel plate flow chamber on a 16 h pellicle coated surface. After detachment by perfusing the chamber with a dentifrice, re-deposition was initiated by flowing with a fresh streptococcal suspension. The dentifrices included both a regular, SLS-fluoride based formulation as well a pyrophosphate, anticalculus and antimicrobial formulations. All dentifrice supernates containing SLS were effective in detaching co-adhering bacteria from pellicles surfaces, except in combination with SnF(2). When hexametaphosphate was added immediate detachment was relatively low, but continued even during re-deposition. The re-deposition of streptococci after detachment by other, NaF containing dentifrices involved relatively few large aggregates, presumably because fluoride was able to block bi-dentate calcium binding sites on the bacterial cell surfaces, mediating co-adhesion. When pyrophosphate was present in addition to NaF, re-deposition involved significantly more large aggregates, likely because pyrophosphate served as a bi-dentate bridge between calcium bound on the bacterial cell surfaces. Commercially available dentifrice formulations differ in their ability to stimulate bacterial detachment from pellicles and dependent on their composition yield the formation of large co-adhering aggregates of actinomyces and streptococci in de novo deposition.

Adherent and Invasive Escherichia coli Is Associated with Granulomatous Colitis in Boxer Dogs

PubMed Central

Simpson, Kenneth W.; Dogan, Belgin; Rishniw, Mark; Goldstein, Richard E.; Klaessig, Suzanne; McDonough, Patrick L.; German, Alex J.; Yates, Robin M.; Russell, David G.; Johnson, Susan E.; Berg, Douglas E.; Harel, Josee; Bruant, Guillaume; McDonough, Sean P.; Schukken, Ynte H.

2006-01-01

The mucosa-associated microflora is increasingly considered to play a pivotal role in the pathogenesis of inflammatory bowel disease. This study explored the possibility that an abnormal mucosal flora is involved in the etiopathogenesis of granulomatous colitis of Boxer dogs (GCB). Colonic biopsy samples from affected dogs (n = 13) and controls (n = 38) were examined by fluorescent in situ hybridization (FISH) with a eubacterial 16S rRNA probe. Culture, 16S ribosomal DNA sequencing, and histochemistry were used to guide subsequent FISH. GCB-associated Escherichia coli isolates were evaluated for their ability to invade and persist in cultured epithelial cells and macrophages as well as for serotype, phylogenetic group, genome size, overall genotype, and presence of virulence genes. Intramucosal gram-negative coccobacilli were present in 100% of GCB samples but not controls. Invasive bacteria hybridized with FISH probes to E. coli. Three of four GCB-associated E. coli isolates adhered to, invaded, and replicated within cultured epithelial cells. Invasion triggered a “splash”-type response, was decreased by cytochalasin D, genistein, colchicine, and wortmannin, and paralleled the behavior of the Crohn's disease-associated strain E. coli LF 82. GCB E. coli and LF 82 were diverse in serotype and overall genotype but similar in phylogeny (B2 and D), in virulence gene profiles (fyuA, irp1, irp2, chuA, fepC, ibeA, kpsMII, iss), in having a larger genome size than commensal E. coli, and in the presence of novel multilocus sequence types. We conclude that GCB is associated with selective intramucosal colonization by E. coli. E. coli strains associated with GCB and Crohn's disease have an adherent and invasive phenotype and novel multilocus sequence types and resemble E. coli associated with extraintestinal disease in phylogeny and virulence gene profile. PMID:16861666

Chemorepulsion from the Quorum Signal Autoinducer-2 Promotes Helicobacter pylori Biofilm Dispersal

PubMed Central

Anderson, Jeneva K.; Huang, Julie Y.; Wreden, Christopher; Sweeney, Emily Goers; Goers, John; Remington, S. James

2015-01-01

ABSTRACT The gastric pathogen Helicobacter pylori forms biofilms on abiotic and biotic surfaces. We have shown previously that H. pylori perceives the quorum signal autoinducer-2 (AI-2) as a chemorepellent. We report here that H. pylori chemorepulsion from endogenous AI-2 influences the proportions and spatial organization of cells within biofilms. Strains that fail to produce AI-2 (∆luxS strains) or are defective for chemotaxis (∆cheA strains) formed more spatially homogenous biofilms with a greater proportion of adherent versus planktonic cells than wild-type biofilms. Reciprocally, a strain that overproduced AI-2 (luxSOP) formed biofilms with proportionally fewer adherent cells. Along with the known AI-2 chemoreceptor, TlpB, we identified AibA and AibB, two novel periplasmic binding proteins that are required for the AI-2 chemorepulsion response. Disruptions in any of the proteins required for AI-2 chemotaxis recapitulated the biofilm adherence and spatial organization phenotype of the ∆luxS mutant. Furthermore, exogenous administration of AI-2 was sufficient to decrease the proportion of adherent cells in biofilms and promote dispersal of cells from biofilms in a chemotaxis-dependent manner. Finally, we found that disruption of AI-2 production or AI-2 chemotaxis resulted in increased clustering of cells in microcolonies on cultured epithelial cells. We conclude that chemotaxis from AI-2 is a determinant of H. pylori biofilm spatial organization and dispersal. PMID:26152582

Assessment of Adherence to Eating Habit and Exercise Components in a Behavioral Weight Control Program.

ERIC Educational Resources Information Center

Zegman, Marilyn A.

Although the augmental value of exercise to behavioral weight control programs has been suggested, demonstration of this value is dependent upon an assessment of adherence to change in eating habits and activity patterns. Self-report measures of adherence were obtained from overweight college women undergoing treatment that involved either dietary…

Interventions to Improve Medication Adherence among Older Adults: Meta-Analysis of Adherence Outcomes among Randomized Controlled Trials

ERIC Educational Resources Information Center

Conn, Vicki S.; Hafdahl, Adam R.; Cooper, Pamela S.; Ruppar, Todd M.; Mehr, David R.; Russell, Cynthia L.

2009-01-01

Purpose: This study investigated the effectiveness of interventions to improve medication adherence (MA) in older adults. Design and Methods: Meta-analysis was used to synthesize results of 33 published and unpublished randomized controlled trials. Random-effects models were used to estimate overall mean effect sizes (ESs) for MA, knowledge,…

Keratinocyte Motility Is Affected by UVA Radiation-A Comparison between Normal and Dysplastic Cells.

PubMed

Niculiţe, Cristina M; Nechifor, Marina T; Urs, Andreea O; Olariu, Laura; Ceafalan, Laura C; Leabu, Mircea

2018-06-07

UVA radiation induces multiple and complex changes in the skin, affecting epidermal cell behavior. This study reports the effects of UVA exposure on normal (HaCaT) and dysplastic (DOK) keratinocytes. The adherence, spreading and proliferation were investigated by time-lapse measurement of cell layer impedance on different matrix proteins. Prior to UVA exposure, the time required for adherence and spreading did not differ significantly for HaCaT and DOK cells, while spreading areas were larger for HaCaT cells. Under UVA exposure, HaCaT and DOK cells behavior differed in terms of movement and proliferation. The cells' ability to cover the denuded surface and individual cell trajectories were recorded by time-lapse videomicroscopy, during wound healing experiments. Dysplastic keratinocytes showed more sensitivity to UVA, exhibiting transient deficiencies in directionality of movement and a delay in re-coating the denuded area. The actin cytoskeleton displayed a cortical organization immediately after irradiation, in both cell lines, similar to mock-irradiated cells. Post-irradiation, DOK cells displayed a better organization of stress fibers, persistent filopodia, and new, stronger focal contacts. In conclusion, after UVA exposure HaCaT and DOK cells showed a different behavior in terms of adherence, spreading, motility, proliferation, and actin cytoskeleton dynamics, with the dyplastic keratinocytes being more sensitive.

Carbon storage regulator A contributes to the virulence of Haemophilus ducreyi in humans by multiple mechanisms.

PubMed

Gangaiah, Dharanesh; Li, Wei; Fortney, Kate R; Janowicz, Diane M; Ellinger, Sheila; Zwickl, Beth; Katz, Barry P; Spinola, Stanley M

2013-02-01

The carbon storage regulator A (CsrA) controls a wide variety of bacterial processes, including metabolism, adherence, stress responses, and virulence. Haemophilus ducreyi, the causative agent of chancroid, harbors a homolog of csrA. Here, we generated an unmarked, in-frame deletion mutant of csrA to assess its contribution to H. ducreyi pathogenesis. In human inoculation experiments, the csrA mutant was partially attenuated for pustule formation compared to its parent. Deletion of csrA resulted in decreased adherence of H. ducreyi to human foreskin fibroblasts (HFF); Flp1 and Flp2, the determinants of H. ducreyi adherence to HFF cells, were downregulated in the csrA mutant. Compared to its parent, the csrA mutant had a significantly reduced ability to tolerate oxidative stress and heat shock. The enhanced sensitivity of the mutant to oxidative stress was more pronounced in bacteria grown to stationary phase compared to that in bacteria grown to mid-log phase. The csrA mutant also had a significant survival defect within human macrophages when the bacteria were grown to stationary phase but not to mid-log phase. Complementation in trans partially or fully restored the mutant phenotypes. These data suggest that CsrA contributes to virulence by multiple mechanisms and that these contributions may be more profound in bacterial cell populations that are not rapidly dividing in the human host.

Does the presence of placental basal plate myometrial fibres increase the risk of subsequent morbidly adherent placenta: a case-control study.

PubMed

Miller, E S; Linn, R L; Ernst, L M

2016-12-01

Antenatal diagnosis of morbidly adherent placenta has been shown to improve outcomes, but existing predictors lack sensitivity. Our objective was to determine whether the presence of myometrial fibres attached to the placental basal plate (BPMYO) in an antecedent pregnancy is associated with subsequent morbidly adherent placenta. A case-control study. Departments of Obstetrics and Gynecology and Pathology, Northwestern University, Chicago, IL, USA. Women who had at least two pregnancies with placental pathological evaluation. Cases were defined as women with evidence of morbidly adherent placenta (both clinically and pathologically) in their most recent pregnancy whereas women without evidence of morbidly adherent placenta served as controls. Pathological specimens of placentas from previous pregnancies were evaluated for BPMYO. The presence of BPMYO on a previous placenta was evaluated to determine whether it could be used to improve the antenatal diagnosis of morbidly adherent placenta. Of the 25 cases of morbidly adherent placenta, 19 (76%) had BPMYO present on their previous placenta compared with 41 (41%) of controls (odds ratio 4.8, 95% CI 1.8-13.0). Adding BPMYO to a regression including other risk factors for morbidly adherent placenta (i.e. maternal age, number of previous caesarean sections, placenta praevia, previous multiple gestation, any previous curettage, and ultrasonographic suspicion of placenta accreta) significantly improved the sensitivity of antenatal diagnosis of morbidly adherent placenta (61% versus 39%, P < 0.001) without a change in specificity (97% versus 97%, P = 1.00). BPMYO on previous placental pathology is associated with an increased risk of morbidly adherent placenta in a subsequent pregnancy. These findings may shed light on the pathophysiology of accreta and inform future research on predictors of accreta. Previous basal plate myometrium improves the ability to detect subsequent morbidly adherent placenta. © 2015 Royal College of Obstetricians and Gynaecologists.

Human dental stem cells suppress PMN activity after infection with the periodontopathogens Prevotella intermedia and Tannerella forsythia

PubMed Central

Hieke, Cathleen; Kriebel, Katja; Engelmann, Robby; Müller-Hilke, Brigitte; Lang, Hermann; Kreikemeyer, Bernd

2016-01-01

Periodontitis is characterized by inflammation associated with the colonization of different oral pathogens. We here aimed to investigate how bacteria and host cells shape their environment in order to limit inflammation and tissue damage in the presence of the pathogen. Human dental follicle stem cells (hDFSCs) were co-cultured with gram-negative P. intermedia and T. forsythia and were quantified for adherence and internalization as well as migration and interleukin secretion. To delineate hDFSC-specific effects, gingival epithelial cells (Ca9-22) were used as controls. Direct effects of hDFSCs on neutrophils (PMN) after interaction with bacteria were analyzed via chemotactic attraction, phagocytic activity and NET formation. We show that P. intermedia and T. forsythia adhere to and internalize into hDFSCs. This infection decreased the migratory capacity of the hDFSCs by 50%, did not disturb hDFSC differentiation potential and provoked an increase in IL-6 and IL-8 secretion while leaving IL-10 levels unaltered. These environmental modulations correlated with reduced PMN chemotaxis, phagocytic activity and NET formation. Our results suggest that P. intermedia and T. forsythia infected hDFSCs maintain their stem cell functionality, reduce PMN-induced tissue and bone degradation via suppression of PMN-activity, and at the same time allow for the survival of the oral pathogens. PMID:27974831

Characterization of bone marrow mesenchymal stromal cells in aplastic anaemia.

PubMed

Hamzic, Edita; Whiting, Karen; Gordon Smith, Edward; Pettengell, Ruth

2015-06-01

In aplastic anaemia (AA), haemopoietic activity is significantly reduced and generally attributed to failure of haemopoietic stem cells (HSC) within the bone marrow (BM). The regulation of haemopoiesis depends on the interaction between HSC and various cells of the BM microenvironment, including mesenchymal stromal cells (MSC). MSC involvement in the functional restriction of HSC in AA is largely unknown and therefore, the physical and functional properties of AA MSC were studied in vitro. MSC were characterized by their phenotype and ability to form adherent stromal layers. The functional properties of AA MSC were assessed through proliferative, clonogenic and cross-over culture assays. Results indicate that although AA MSC presented typical morphology and distinctive mesenchymal markers, stromal formation was reduced, with 50% of BM samples failing to produce adherent layers. Furthermore, their proliferative and clonogenic capacity was markedly decreased (P = 0·03 and P = 0·04 respectively) and the ability to sustain haemopoiesis was significantly reduced, as assessed by total cell proliferation (P = 0·032 and P = 0·019 at Week 5 and 6, respectively) and clonogenic potential of HSC (P = 0·02 at Week 6). It was concluded that the biological characteristics of AA MSC are different from those of control MSC and their in vitro haemopoiesis-supporting ability is significantly reduced. © 2015 John Wiley & Sons Ltd.

Pathways from emotional adjustment to glycemic control in youths with diabetes in Hong Kong.

PubMed

Stewart, S M; Lee, P W; Low, L C; Cheng, A; Yeung, W; Huen, K F; O'Donnell, D

2000-09-01

To examine factors that influence emotional adjustment, adherence to diabetic care, and glycemic control in Hong Kong youths with insulin-dependent diabetes mellitus (IDDM). Seventy youths, their mothers, and matched controls provided information on health beliefs, authoritarian parenting style, parent-child conflict, emotional adjustment, and adherence to medical regimen. Glycosylated hemoglobin levels were obtained to measure glycemic control. Predictors explained 34% of the variance in emotional adjustment and 39% of the variance in glycemic control. The data supported a pathway from emotional adjustment to self-efficacy to adherence behaviors to glycemic control. In contrast to Western culture and consistent with prediction, parenting style did not associate with negative outcomes, and even relatively low levels of parent-child conflict correlated negatively with emotional adjustment in this culture. Management of conflict and self-efficacy enhancing interactions are suggested interventions to enhance adherence to diabetic care in Hong Kong youths with IDDM.

Illness perception, coping and adherence to treatment among patients with chronic kidney disease.

PubMed

Vélez-Vélez, Esperanza; Bosch, Ricardo J

2016-04-01

To analyse the predictive value of illness representations on treatment adherence and coping strategies in a group of patients on haemodialysis. Understanding the cognitive and emotional factors that influence adherence behaviour and coping strategies and determining their relationship to sociodemographic factors remain a challenge; meeting this challenge would encourage comprehensive patient care, thereby improving their quality of life Cross-sectional study with predictive means in a sample of 135 patients on haemodialysis. Data collection occurred from September 2010-January 2012 and tools included the following: sociodemographic data, Illness Perception Questionnaire-Revised, the Cuestionario de Afrontamiento del Estrés and the Morisky-Green test to study adherence to treatment. Being a woman, having a greater knowledge of the disease and having a poorer sense of personal control affected adherence to treatment on controlling for each factor. 'Identity', 'personal control' and 'adherence' were associated with a proactive coping strategy, whereas 'evolution' and 'gender' were related independently to avoidance coping strategies; those who believed that their illness had a chronic course were more likely to cope by avoiding the problem and this tendency was stronger among women. This study provides evidence supporting the role of gender, knowledge about the disease and sense of personal control in adherence to therapeutic regimens of patients in chronic haemodialysis. The identification and characterization of patients' perception of chronic illness may represent a useful framework to influence disease outcomes such as adherence. © 2015 John Wiley & Sons Ltd.

Human antibodies to PhtD, PcpA, and Ply reduce adherence to human lung epithelial cells and murine nasopharyngeal colonization by Streptococcus pneumoniae.

PubMed

Kaur, Ravinder; Surendran, Naveen; Ochs, Martina; Pichichero, Michael E

2014-12-01

Streptococcus pneumoniae adherence to human epithelial cells (HECs) is the first step in pathogenesis leading to infections. We sought to determine the role of human antibodies against S. pneumoniae protein vaccine candidates PhtD, PcpA, and Ply in preventing adherence to lung HECs in vitro and mouse nasopharyngeal (NP) colonization in vivo. Human anti-PhtD, -PcpA, and -Ply antibodies were purified and Fab fragments generated. Fabs were used to test inhibition of adherence of TIGR4 and nonencapsulated strain RX1 to A549 lung HECs. The roles of individual proteins in adherence were tested using isogenic mutants of strain TIGR4. Anti-PhtD, -PcpA, and -Ply human antibodies were assessed for their ability to inhibit NP colonization in vivo by passive transfer of human antibody in a murine model. Human antibodies generated against PhtD and PcpA caused a decrease in adherence to A549 cells (P < 0.05). Anti-PhtD but not anti-PcpA antibodies showed a protective role against mouse NP colonization. To our surprise, anti-Ply antibodies also caused a significant (P < 0.05) reduction in S. pneumoniae colonization. Our results support the potential of PhtD, PcpA, and Ply protein vaccine candidates as alternatives to conjugate vaccines to prevent non-serotype-specific S. pneumoniae colonization and invasive infection. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Effects of kefir fractions on innate immunity.

PubMed

Vinderola, Gabriel; Perdigon, Gabriela; Duarte, Jairo; Thangavel, Deepa; Farnworth, Edward; Matar, Chantal

2006-01-01

Innate immunity that protects against pathogens in the tissues and circulation is the first line of defense in the immune reaction, where macrophages have a critical role in directing the fate of the infection. We recently demonstrated that kefir modulates the immune response in mice, increasing the number of IgA+ cells in the intestinal and bronchial mucosa and the phagocytic activity of peritoneal and pulmonary macrophages. The aim of this study was to further characterize the immunomodulating capacity of the two fractions of kefir (F1: solids including bacteria and F2: liquid supernatant), by studying the cytokines produced by cells from the innate immune system: peritoneal macrophages and the adherent cells from Peyer's patches. BALB/c mice were fed either kefir solid fraction (F1) or kefir supernatant (F2) for 2, 5 or 7 consecutive days. The number of cytokine (IL-1alpha, IFNgamma, TNFalpha, IL-6 and IL-10) producing cells was determined on peritoneal macrophages and adherent cells from Peyer's patches. Both kefir fractions (F1 and F2) induced similar cytokine profiles on peritoneal macrophages (only TNFalpha and IL-6 were up-regulated). All cytokines studied on adherent cells from Peyer's patches were enhanced after F1 and F2 feeding, except for IFNgamma after F2 administration. Moreover, the percentage of IL-10+cells induced by fraction F2 on adherent cells from Peyer's patches was significantly higher than the one induced by fraction F1. Different components of kefir have an in vivo role as oral biotherapeutic substances capable of stimulating immune cells of the innate immune system, to down-regulate the Th2 immune phenotype or to promote cell-mediated immune responses against tumours and also against intracellular pathogenic infections.

STANDARDIZATION OF A FLUORESCENT-BASED QUANTITATIVE ADHESION ASSAY TO STUDY ATTACHMENT OF Taenia solium ONCOSPHERE TO EPITHELIAL CELLS In Vitro

PubMed Central

Chile, Nancy; Evangelista, Julio; Gilman, Robert H.; Arana, Yanina; Palma, Sandra; Sterling, Charles R; Garcia, Hector H.; Gonzalez, Armando; Verastegui, Manuela

2012-01-01

To fully understand the preliminary stages of Taenia solium oncosphere attachment in the gut, adequate tools and assays are necessary to observe and quantify this event that leads to infection. A fluorescent-based quantitative adhesion assay, using biotinylated activated-oncospheres and monolayers of Chinese hamster ovary cells (CHO-K1) or human intestinal monolayer cells (INT-407, HCT-8 or HT-29), was developed to study initial events during the infection of target cells and to rapidly quantify the in vitro adhesion of T. solium oncospheres. Fluorescein streptavidin was used to identify biotinylated activated-oncospheres adhered to cells. This adherence was quantified using an automated fluorescence plate reader, and the results were expressed as fluorescence intensity values. A series of three assays were performed. The first was to identify the optimum number of biotinylated activated-oncospheres to be used in the adhesion assay. The goal of the second assay was to validate this novel method with the established oncosphere-binding system using the immunofluorescent-antibody assay (IFA) method to quantify oncosphere adhesion. A total of 10,000 biotinylated activated-oncospheres were utilized to assess the role of sera and laminin (LM) in oncosphere adherence to a CHO-K1 cell monolayer. The findings that sera and LM increase the adhesion of oncospheres to monolayer cells were similar to results that were previously obtained using the IFA method. The third assay compared the adherence of biotinylated activated-oncospheres to different types of human intestinal monolayer cells. In this case, the fluorescence intensity was greatest when using the INT-407 cell monolayer. We believe this new method of quantification offers the potential for rapid, large-scale screening to study and elucidate specific molecules and mechanisms involved in oncosphere-host cell attachment. PMID:22178422

Using the theory of planned behavior to improve treatment adherence in Mexican Americans with schizophrenia.

PubMed

Kopelowicz, Alex; Zarate, Roberto; Wallace, Charles J; Liberman, Robert Paul; Lopez, Steven R; Mintz, Jim

2015-10-01

Failure to adhere to treatment with antipsychotic medication is the most common cause of relapse among patients with schizophrenia. A novel multifamily group (MFG) intervention, informed by the Theory of Planned Behavior (TPB), demonstrated efficacy in increasing medication adherence and decreasing rehospitalizations in schizophrenia patients. This report explores the hypothesis that the improved outcomes obtained through the MFG approach were mediated by changes in the patients' attitudes toward medications, subjective norms-social influences, and perceived behavioral control of resources. Data from a recently completed, randomized controlled trial of MFG was used to test the hypothesis that the improvement in adherence was mediated by the 3 TPB factors. Subjects were 174 Mexican American adults with schizophrenia-spectrum disorder who had participated in a study of MFG focused on improving medication adherence. Assessments occurred at baseline and at 4, 8, 12, 18, and 24 months. Path analysis revealed that the increased adherence associated with MFG was mediated by improvements in subjective norms but not attitudes toward medications nor perceived behavioral control. An MFG treatment specifically tailored to increase medication adherence among Mexican Americans with schizophrenia achieved its benefits by leveraging social influences through teaching family members how to support medication adherence in their ill relatives. (c) 2015 APA, all rights reserved).

Using the Theory of Planned Behavior to Improve Treatment Adherence in Mexican Americans with Schizophrenia

PubMed Central

Kopelowicz, Alex; Zarate, Roberto; Wallace, Charles J.; Liberman, Robert Paul; Lopez, Steven R.; Mintz, Jim

2015-01-01

Objective Failure to adhere to treatment with antipsychotic medication is the most common cause of relapse among patients with schizophrenia. A novel multi-family group (MFG) intervention, informed by the Theory of Planned Behavior (TPB), demonstrated efficacy in increasing medication adherence and decreasing re-hospitalizations in schizophrenia patients. This report explores the hypothesis that the improved outcomes obtained through the MFG approach were mediated by changes in the patients’ attitudes towards medications, subjective norms-social influences, and perceived behavioral control of resources. Method Data from a recently completed, randomized controlled trial of MFG was used to test the hypothesis that the improvement in adherence was mediated by the three TPB factors. Subjects were 174 Mexican American adults with schizophrenia-spectrum disorder who had participated in a study of MFG focused on improving medication adherence. Assessments occurred at baseline and at 4, 8, 12, 18 and 24 months. Results Path analysis revealed that the increased adherence associated with MFG was mediated by improvements in subjective norms but not attitudes towards medications nor perceived behavioral control. Conclusion An MFG treatment specifically tailored to increase medication adherence among Mexican Americans with schizophrenia achieved its benefits by leveraging social influences through teaching family members how to support medication adherence in their ill relatives. PMID:26030760

The Role of Authoritative Parenting in Adolescent Type 1 Diabetes Management.

PubMed

Radcliff, Zach; Weaver, Patrick; Chen, Rusan; Streisand, Randi; Holmes, Clarissa

2018-03-01

Adolescents with Type 1 diabetes are at risk for poorer adherence, lower quality of life (QOL), and poorer glycemic control (HbA1c). Authoritative parenting (AP) along with youth adherence and QOL was hypothesized to relate to better HbA1c. Parent-youth dyads (N = 257) completed baseline measures of adherence and QOL. Youth completed an AP questionnaire, and HbA1c samples were evaluated. Structural equation modeling determined relations among AP, adherence, QOL, and glycemic control. AP indirectly linked to better HbA1c (β = -.15, p = .021) through both better adherence and higher QOL. AP also was associated directly with better adherence (β = .26, p = .001), which in turn was linked to better HbA1c (β = -.35, p = .021). In addition, adherence was associated directly with QOL (β = -.56, p = .001). Together, better youth adherence and higher QOL are two mechanisms by which more AP indirectly relates to better glycemic control during the early adolescent years. © The Author 2017. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

Inhaled corticosteroid adherence and emergency department utilization among Medicaid-enrolled children with asthma

PubMed Central

Rust, George; Zhang, Shun; Reynolds, Joshua

2014-01-01

Objectives Asthma is the most prevalent chronic disease among children enrolled in Medicaid. This study measured real-world adherence and outcomes after an initial prescription for inhaled corticosteroid therapy in a multi-state Medicaid population. Methods We conducted a retrospective study among Medicaid-enrolled children aged 5–12 years with asthma in 14 southern states using 2007 Medicaid Analytic eXtract file claims data to assess adherence and outcomes over the 3 months following an initial prescription drug claim for inhaled corticosteroids (ICS-Rx). Adherence was measured by the long-term controller-to-total asthma drug claims ratio. Results Only one-third of children (33.4%) with an initial ICS-Rx achieved a controller-to-total drug ratio >0.5 over the next 90 days. Children for whom long-term control drugs represented less than half of their total asthma drug claims had a 21% higher risk of emergency department (ED) visit (adjusted odds ratio (AOR) 1.21 [95% CI 1.14, 1.27]), and a 70% higher risk of hospital admission (AOR 1.70 [95% CI 1.45, 1.98]) than those with a controller-to-total asthma drug ratio >0.5. Conclusion Real-world adherence to long-term controller medications is quite low in this racially diverse, low-income segment of the population, despite Medicaid coverage of medications. Adherence to long-term controller therapy had a measurable impact on real-world outcomes. Medicaid programs are a potential surveillance system for both medication adherence and ED utilization. PMID:23734973

Substrate effects on endothelial cell adherence rates.

PubMed

Scott, W J; Mann, P

1990-01-01

Endothelial cell attachment to a synthetic substrate was studied using an in vitro model system. Attachment rate was defined as the number of tritium-labeled endothelial cells attached to a synthetic substrate after 30 minutes. The surface of the synthetic substrate was chemically modified with either laminin or fibronectin. Labeled endothelial cells attached more rapidly to synthetic substrate, chemically modified with biomolecules, as compared with the untreated substrate controls. Unlabeled endothelial cells were grown to confluency on a second set of modified and untreated substrates. The cells were removed with 1% Triton, and the rate of re-endothelialization with tritium-labeled endothelial cells was determined. The rate was 11-13 times that of the same cells on untreated substrate. These data confirm that biomolecules increase the attachment rate of endothelial cells to synthetic substrate, and also suggest that endothelial cells may secrete a Triton-insoluble product (Sigma, St. Louis, MO) into subendothelial matrix that increases re-endothelialization.

Application of Organosilane Monolayer Template to Quantitative Evaluation of Cancer Cell Adhesive Ability

NASA Astrophysics Data System (ADS)

Tanii, Takashi; Sasaki, Kosuke; Ichisawa, Kota; Demura, Takanori; Beppu, Yuichi; Vu, Hoan Anh; Thanh Chi, Hoan; Yamamoto, Hideaki; Sato, Yuko

2011-06-01

The adhesive ability of two human pancreatic cancer cell lines was evaluated using organosilane monolayer templates (OMTs). Using the OMT, the spreading area of adhered cells can be limited, and this enables us to focus on the initial attachment process of adhesion. Moreover, it becomes possible to arrange the cells in an array and to quantitatively evaluate the number of attached cells. The adhesive ability of the cancer cells cultured on the OMT was controlled by adding (-)-epigallocatechin-3-gallate (EGCG), which blocks a receptor that mediates cell adhesion and is overexpressed in cancer cells. Measurement of the relative ability of the cancer cells to attach to the OMT revealed that the ability for attachment decreased with increasing EGCG concentration. The results agreed well with the western blot analysis, indicating that the OMT can potentially be employed to evaluate the adhesive ability of various cancer cells.

Bacillus Anthracis Spores of the bclA Mutant Exhibit Increased Adherence to Epithelial Cells, Fibroblasts, and Endothelial Cells but not to Macrophages

DTIC Science & Technology

2007-09-01

immunofluorescence (IFM) and light microscopy. Samples were fixed in forma- lin, stained with immunofluorescent dyes (as described below) or spore stain ( malachite ...BEC. Adherence was assessed by microscopic observation of the infected cells stained with malachite green and counterstaining of the BEC. For enzymatic...this significant difference, BEC infected with spores were stained with malachite green and counter- stained with Wright-Giemsa (Fig. 1B and C). This

Evaluation of a nurse-led disease management programme for chronic kidney disease: a randomized controlled trial.

PubMed

Wong, Frances Kam Yuet; Chow, Susan Ka Yee; Chan, Tony Moon Fai

2010-03-01

Patients with end stage renal failure require dialysis and strict adherence to treatment plans to sustain life. However, non-adherence is a common and serious problem among patients with chronic kidney disease. There is a scarcity of studies in examining the effects of disease management programmes on patients with chronic kidney disease. This paper examines whether the study group receiving the disease management programme have better improvement than the control group, comparing outcomes at baseline (O1), at 7 weeks at the completion of the programme (O2) and at 13 weeks (O3). This is a randomized controlled trial. The outcome measures were non-adherence in diet, fluid, dialysis and medication, quality of life, satisfaction, symptom control, complication control and health service utilisation. There was no significant difference between the control and study group for the baseline measures, except for sleep. Significant differences (p<0.05) were found between the control and study group at O2 in the outcome measures of diet degree non-adherence, sleep, symptom, staff encouragement, overall health and satisfaction. Sustained effects at O3 were noted in the outcome measures of continuous ambulatory peritoneal dialysis (CAPD) non-adherence degree, sleep, symptom, and effect of kidney disease. Many studies exploring chronic disease management have neglected the group with end stage renal failure and this study fills this gap. This study has employed an innovative model of skill mix using specialist and general nurses and demonstrated patient improvement in diet non-adherence, CAPD non-adherence, aspects of quality of life and satisfaction with care. Redesigning chronic disease management programmes helps to optimize the use of different levels of skills and resources to bring about positive outcomes. Copyright 2009 Elsevier Ltd. All rights reserved.

Continuous Positive Airway Pressure Adherence In Patients with Obstructive Sleep Apnea & Symptomatic BPH.

PubMed

Metta, Ramesh V V S; Zaka, Awais; Lee, Vincent C; Mador, M Jeffery

2017-04-01

Purpose To determine the short-term and long-term adherence rates with continuous positive airway pressure (CPAP) therapy in sleep apnea patients with benign prostatic hyperplasia (BPH) compared to matched controls. Methods A case-control retrospective analysis was performed in a veterans affairs hospital. All symptomatic patients with BPH (n = 107) ever started on CPAP therapy between 2006 and 2012 were compared with controls matched for severity of sleep apnea (AHI). Adherence measures were obtained at the third and twelfth month visits. The cases included symptomatic BPH patients on active medical therapy. Diuretic use among cases and controls, and severity of nocturia among the cases were also analyzed. Results The mean AHI among cases and controls was 35.6 ± 27.3 and 35.5 ± 31 (p = 0.96). The population was male and predominantly Caucasian. There was no statistically significant difference in percent days CPAP device use ≥4 h. between symptomatic BPH patients and controls at 3-month (51.6 ± 38 vs. 47.2 ± 36; p = 0.43) and 1-year (64 ± 40.5 vs. 64.7 ± 31.3; p = 0.90) visits. The use of diuretics in the cases and controls, and the severity of nocturia in the cases did not influence adherence with CPAP therapy. Conclusions BPH or diuretic use did not affect adherence with CPAP therapy in obstructive sleep apnea. Severity of nocturia did not have any influence on adherence among the cases. BPH, regardless of the severity of nocturia, and diuretic use does not influence CPAP adherence in patients with OSA.

E-selectin ligand-1 controls circulating prostate cancer cell rolling/adhesion and metastasis

PubMed Central

Yasmin-Karim, Sayeda; King, Michael R.; Messing, Edward M.; Lee, Yi-Fen

2014-01-01

Circulating prostate cancer (PCa) cells preferentially roll and adhere on bone marrow vascular endothelial cells, where abundant E-selectin and stromal cell-derived factor 1 (SDF-1) are expressed, subsequently initiating a cascade of activation events that eventually lead to the development of metastases. To elucidate the roles of circulating PCa cells' rolling and adhesion behaviors in cancer metastases, we applied a dynamic cylindrical flow-based microchannel device that is coated with E-selectin and SDF-1, mimicking capillary endothelium. Using this device we captured a small fraction of rolling PCa cells. These rolling cells display higher static adhesion ability, more aggressive cancer phenotypes and stem-like properties. Importantly, mice received rolling PCa cells, but not floating PCa cells, developed cancer metastases. Genes coding for E-selectin ligands and genes associated with cancer stem cells and metastasis were elevated in rolling PCa cells. Knock down of E-selectin ligand 1(ESL-1), significantly impaired PCa cells' rolling capacity and reduced cancer aggressiveness. Moreover, ESL-1 activates RAS and MAP kinase signal cascade, consequently inducing the downstream targets. In summary, circulating PCa cells' rolling capacity contributes to PCa metastasis, and that is in part controlled by ESL-1. PMID:25301730

Physical Biology in Cancer. 3. The role of cell glycocalyx in vascular transport of circulating tumor cells

PubMed Central

Mitchell, Michael J.

2013-01-01

Circulating tumor cells (CTCs) in blood are known to adhere to the luminal surface of the microvasculature via receptor-mediated adhesion, which contributes to the spread of cancer metastasis to anatomically distant organs. Such interactions between ligands on CTCs and endothelial cell-bound surface receptors are sensitive to receptor-ligand distances at the nanoscale. The sugar-rich coating expressed on the surface of CTCs and endothelial cells, known as the glycocalyx, serves as a physical structure that can control the spacing and, thus, the availability of such receptor-ligand interactions. The cancer cell glycocalyx can also regulate the ability of therapeutic ligands to bind to CTCs in the bloodstream. Here, we review the role of cell glycocalyx on the adhesion and therapeutic treatment of CTCs in the bloodstream. PMID:24133067

Towards high-throughput automated targeted femtosecond laser-based transfection of adherent cells

NASA Astrophysics Data System (ADS)

Antkowiak, Maciej; Torres-Mapa, Maria Leilani; Gunn-Moore, Frank; Dholakia, Kishan

2011-03-01

Femtosecond laser induced cell membrane poration has proven to be an attractive alternative to the classical methods of drug and gene delivery. It is a selective, sterile, non-contact technique that offers a highly localized operation, low toxicity and consistent performance. However, its broader application still requires the development of robust, high-throughput and user-friendly systems. We present a system capable of unassisted enhanced targeted optoinjection and phototransfection of adherent mammalian cells with a femtosecond laser. We demonstrate the advantages of a dynamic diffractive optical element, namely a spatial light modulator (SLM) for precise three dimensional positioning of the beam. It enables the implementation of a "point-and-shoot" system in which using the software interface a user simply points at the cell and a predefined sequence of precisely positioned doses can be applied. We show that irradiation in three axial positions alleviates the problem of exact beam positioning on the cell membrane and doubles the number of viably optoinjected cells when compared with a single dose. The presented system enables untargeted raster scan irradiation which provides transfection of adherent cells at the throughput of 1 cell per second.

Computer-based intervention in HIV clinical care setting improves antiretroviral adherence: the LifeWindows Project.

PubMed

Fisher, Jeffrey D; Amico, K Rivet; Fisher, William A; Cornman, Deborah H; Shuper, Paul A; Trayling, Cynthia; Redding, Caroline; Barta, William; Lemieux, Anthony F; Altice, Frederick L; Dieckhaus, Kevin; Friedland, Gerald

2011-11-01

We evaluated the efficacy of LifeWindows, a theory-based, computer-administered antiretroviral (ARV) therapy adherence support intervention, delivered to HIV + patients at routine clinical care visits. 594 HIV + adults receiving HIV care at five clinics were randomized to intervention or control arms. Intervention vs. control impact in the intent-to-treat sample (including participants whose ARVs had been entirely discontinued, who infrequently attended care, or infrequently used LifeWindows) did not reach significance. Intervention impact in the On Protocol sample (328 intervention and control arm participants whose ARVs were not discontinued, who attended care and were exposed to LifeWindows regularly) was significant. On Protocol intervention vs. control participants achieved significantly higher levels of perfect 3-day ACTG-assessed adherence over time, with sensitivity analyses maintaining this effect down to 70% adherence. This study supports the utility of LifeWindows and illustrates that patients on ARVs who persist in care at clinical care sites can benefit from adherence promotion software.

Community health workers improve disease control and medication adherence among patients with diabetes and/or hypertension in Chiapas, Mexico: an observational stepped-wedge study

PubMed Central

Franke, Molly F; Arrieta, Jafet; Carrasco, Hector; Elliott, Patrick; Flores, Hugo; Friedman, Alexandra; Graham, Sophia; Martinez, Luis; Palazuelos, Lindsay; Savage, Kevin; Tymeson, Hayley; Palazuelos, Daniel

2018-01-01

Background Non-communicable diseases (NCDs) contribute greatly to morbidity and mortality in low-income and middle-income countries (LMICs). Community health workers (CHWs) may improve disease control and medication adherence among patients with NCDs in LMICs, but data are lacking. We assessed the impact of a CHW-led intervention on disease control and adherence among patients with diabetes and/or hypertension in Chiapas, Mexico. Methods We conducted a prospective observational study among adult patients with diabetes and/or hypertension, in the context of a stepped-wedge roll-out of a CHW-led intervention. We measured self-reported adherence to medications, blood pressure and haemoglobin A1c at baseline and every 3 months, timed just prior to expansion of the intervention to a new community. We conducted individual-level mixed effects analyses of study data, adjusting for time and clustering by patient and community. Findings We analysed 108 patients. The CHW-led intervention was associated with a twofold increase in the odds of disease control (OR 2.04, 95% CI 1.15 to 3.62). It was also associated with optimal adherence assessed by 30-day recall (OR 1.86; 95% CI 1.15 to 3.02) and a positive self-assessment of adherence behaviour (OR 2.29; 95% CI 1.26 to 4.15), but not by 5-day recall. Interpretation A CHW-led adherence intervention was associated with disease control and adherence among adults with diabetes and/or hypertension. This study supports a role of CHWs in supplementing comprehensive primary care for patients with NCDs in LMICs. Trial registration number NCT02549495. PMID:29527344

Saliva and dental plaque.

PubMed

Rudney, J D

2000-12-01

Dental plaque is being redefined as oral biofilm. Diverse overlapping microbial consortia are present on all oral tissues. Biofilms are structured, displaying features like channels and projections. Constituent species switch back and forth between sessile and planktonic phases. Saliva is the medium for planktonic suspension. Several major functions can be defined for saliva in relation to oral biofilm. It serves as a medium for transporting planktonic bacteria within and between mouths. Bacteria in transit may be vulnerable to negative selection. Salivary agglutinins may prevent reattachment to surfaces. Killing by antimicrobial proteins may lead to attachment of dead cells. Salivary proteins form conditioning films on all oral surfaces. This contributes to positive selection for microbial adherence. Saliva carries chemical messengers which allow live adherent cells to sense a critical density of conspecifics. Growth begins, and thick biofilms may become resistant to antimicrobial substances. Salivary macromolecules may be catabolized, but salivary flow also may clear dietary substrates. Salivary proteins act in ways that benefit both host and microbe. All have multiple functions, and many do the same job. They form heterotypic complexes, which may exist in large micelle-like structures. These issues make it useful to compare subjects whose saliva functions differently. We have developed a simultaneous assay for aggregation, killing, live adherence, and dead adherence of oral species. Screening of 149 subjects has defined high killing/low adherence, low killing/high adherence, high killing/high adherence, and low killing/low adherence groups. These will be evaluated for differences in their flora.

Effect of cost sharing on adherence to evidence-based medications in patients with acute coronary syndrome

PubMed Central

González López-Valcárcel, Beatriz; Librero, Julián; García-Sempere, Aníbal; Peña, Luz María; Bauer, Sofía; Puig-Junoy, Jaume; Oliva, Juan; Peiró, Salvador; Sanfélix-Gimeno, Gabriel

2017-01-01

Objectives Cost-sharing scheme for pharmaceuticals in Spain changed in July 2012. Our aim was to assess the impact of this change on adherence to essential medication in patients with acute coronary syndrome (ACS) in the region of Valencia. Methods Population-based retrospective cohort of 10 563 patients discharged alive after an ACS in 2009–2011. We examined a control group (low-income working population) that did not change their coinsurance status, and two intervention groups: pensioners who moved from full coverage to 10% coinsurance and middle-income to high-income working population, for whom coinsurance rose from 40% to 50% or 60%. Weekly adherence rates measured from the date of the first prescription. Days with available medication were estimated by linking prescribed and filled medications during the follow-up period. Results Cost-sharing change made no significant differences in adherence between intervention and control groups for essential medications with low price and low patient maximum coinsurance, such as antiplatelet and beta-blockers. For costlier ACE inhibitor or an angiotensin II receptor blocker (ACEI/ARB) and statins, it had an immediate effect in the proportion of adherence in the pensioner group as compared with the control group (6.8% and 8.3% decrease of adherence, respectively, p<0.01 for both). Adherence to statins decreased for the middle-income to high-income group as compared with the control group (7.8% increase of non-adherence, p<0.01). These effects seemed temporary. Conclusions Coinsurance changes may lead to decreased adherence to proven, effective therapies, especially for higher priced agents with higher patient cost share. Consideration should be given to fully exempt high-risk patients from drug cost sharing. PMID:28249992

Adherence to Preexposure Prophylaxis: Current, Emerging, and Anticipated Bases of Evidence

PubMed Central

Amico, K. Rivet; Stirratt, Michael J.

2014-01-01

Despite considerable discussion and debate about adherence to preexposure prophylaxis (PrEP) for human immunodeficiency virus (HIV), scant data are available that characterize patterns of adherence to open-label PrEP. The current evidence base is instead dominated by research on adherence to placebo-controlled investigational drug by way of drug detection in active-arm participants of large randomized controlled trials (RCTs). Important differences between the context of blinded RCTs and open-label use suggest caution when generalizing from study product adherence to real-world PrEP use. Evidence specific to open-label PrEP adherence is presently sparse but will expand rapidly over the next few years as roll-out, demonstration projects, and more rigorous research collect and present findings. The current evidence bases established cannot yet predict uptake, adherence, or persistence with open-label effective PrEP. Emerging evidence suggests that some cohorts could execute better adherence in open-label use vs placebo-controlled research. Uptake of PrEP is presently slow in the United States; whether this changes as grassroots and community efforts increase awareness of PrEP as an effective HIV prevention option remains to be determined. As recommended by multiple guidelines for PrEP use, all current demonstration projects offer PrEP education and/or counseling. PrEP support approaches generally fall into community-based, technology, monitoring, and integrated sexual health promotion approaches. Developing and implementing research that moves beyond simple correlates of either study product use or open-label PrEP adherence toward more comprehensive models of sociobehavioral and socioecological adherence determinants would greatly accelerate progress. Intervention research is needed to identify effective models of support for open-label PrEP adherence. PMID:24926036

Implementation of a Novel Adherence Monitoring Strategy in a Phase III, Blinded, Placebo-Controlled, HIV-1 Prevention Clinical Trial.

PubMed

Husnik, Marla J; Brown, Elizabeth R; Marzinke, Mark; Livant, Edward; Palanee-Phillips, Thesla; Hendrix, Craig W; Matovu Kiweewa, Flavia; Nair, Gonasagrie; Soto-Torres, Lydia E; Schwartz, Katie; Hillier, Sharon L; Baeten, Jared M

2017-11-01

Placebo-controlled HIV-1 prevention trials of pre-exposure prophylaxis (PrEP) have not generally used concurrent measurement of adherence because of the potential risk of unblinding. However, several pre-exposure prophylaxis trials for HIV-1 prevention among women failed to show effectiveness because of low product adherence. Evaluation of product adherence objectively during a study provides the opportunity for strengthening adherence activities at sites having low adherence. During MTN-020/ASPIRE, a phase III, placebo-controlled trial of the dapivirine intravaginal ring, we implemented an adherence monitoring system. Monitoring began in quarter 1 (Q1) 2013 and continued through the conclusion of the trial. Blood plasma was collected quarterly and tested for dapivirine concentrations while maintaining blinding among study team members involved in participant management. Dapivirine concentrations >95 pg/mL, reflecting >8 hours of continuous use, were assessed as signaling product use. Study leadership monitored results on a monthly basis and provided feedback to site investigators. Experiences were shared across sites to motivate staff and counsel participants to strive toward higher adherence levels. An upward trend in adherence was observed (P < 0.0001); the proportion of samples from subjects in the active arm with dapivirine >95 pg/mL increased from 63% in Q1 2013 to 84% by Q1 2015. Ongoing drug level testing as a marker of adherence in MTN-020/ASPIRE demonstrates the feasibility of real-time adherence monitoring while maintaining study blinding at the level of participants, sites, and study leadership. This approach is novel for large-scale effectiveness studies for HIV-1 prevention.

Effect of Motivation by "Instagram" on Adherence to Physical Activity among Female College Students.

PubMed

Al-Eisa, Einas; Al-Rushud, Asma; Alghadir, Ahmad; Anwer, Shahnawaz; Al-Harbi, Bashayer; Al-Sughaier, Noha; Al-Yoseef, Noha; Al-Otaibi, Reem; Al-Muhaysin, Hanadi Ali

2016-01-01

To investigate the efficacy of using "Instagram application" with a "home-exercise program" as a motivational stimulus in improving physical activity (PA) adherence levels among female college students. Fifty-eight female undergraduate students with the mean age 20.3 ± 0.96 years participated. Participants were divided into two groups: intervention and the control group; both the groups received an exercise program and the intervention group was additionally motivated by "Instagram." Adherence to PA was measured by using an adherence sheet. The Exercise Motivation Inventory (EMI-2) was used to assess the motivational factors. The most frequent motivational factors were extrinsic as assessed using the EMI-2. "Positive health" was the most frequent factor mentioned of the two types with 47% of the sample. The intervention group adhered with 17% more to the activity program compared to the control group. Moreover, 72% of the participants in the intervention and control groups found the activity program flexible enough to be performed at home; they agreed about its effectiveness on adherence (53%). The use of Instagram with the home exercise program as a motivational modality could be attractive and effective to reinforce adherence and maintain an appropriate PA level.

Activity of disinfectants against foodborne pathogens in suspension and adhered to stainless steel surfaces

PubMed Central

Cabeça, Tatiane Karen; Pizzolitto, Antonio Carlos; Pizzolitto, Elisabeth Loshchagin

2012-01-01

The purpose of this study was to investigate and compare the efficacy of various disinfectants on planktonic cells and biofilm cells of Listeria monocytogenes, Staphylococcus aureus and Escherichia coli. Numbers of viable biofilm cells decreased after treatment with all tested disinfectants (iodine, biguanide, quaternary ammonium compounds, peracetic acid and sodium hypochlorite). Sodium hypochlorite was the most effective disinfectant against biofilm cells, while biguanide was the least effective. Scanning electron microscopy observations revealed that cells adhered on stainless steel surface after treatment with the disinfectants. No viable planktonic cells were observed after treatment with the same disinfectants. Based on our findings, we concluded that biofilm cells might be more resistant to disinfectants than plancktonic cells. PMID:24031935

Live cell interferometry quantifies dynamics of biomass partitioning during cytokinesis.

PubMed

Zangle, Thomas A; Teitell, Michael A; Reed, Jason

2014-01-01

The equal partitioning of cell mass between daughters is the usual and expected outcome of cytokinesis for self-renewing cells. However, most studies of partitioning during cell division have focused on daughter cell shape symmetry or segregation of chromosomes. Here, we use live cell interferometry (LCI) to quantify the partitioning of daughter cell mass during and following cytokinesis. We use adherent and non-adherent mouse fibroblast and mouse and human lymphocyte cell lines as models and show that, on average, mass asymmetries present at the time of cleavage furrow formation persist through cytokinesis. The addition of multiple cytoskeleton-disrupting agents leads to increased asymmetry in mass partitioning which suggests the absence of active mass partitioning mechanisms after cleavage furrow positioning.

Magnetically levitated mesenchymal stem cell spheroids cultured with a collagen gel maintain phenotype and quiescence

PubMed Central

Lewis, Natasha S; Lewis, Emily EL; Mullin, Margaret; Wheadon, Helen; Dalby, Matthew J; Berry, Catherine C

2017-01-01

Multicellular spheroids are an established system for three-dimensional cell culture. Spheroids are typically generated using hanging drop or non-adherent culture; however, an emerging technique is to use magnetic levitation. Herein, mesenchymal stem cell spheroids were generated using magnetic nanoparticles and subsequently cultured within a type I collagen gel, with a view towards developing a bone marrow niche environment. Cells were loaded with magnetic nanoparticles, and suspended beneath an external magnet, inducing self-assembly of multicellular spheroids. Cells in spheroids were viable and compared to corresponding monolayer controls, maintained stem cell phenotype and were quiescent. Interestingly, core spheroid necrosis was not observed, even with increasing spheroid size, in contrast to other commonly used spheroid systems. This mesenchymal stem cell spheroid culture presents a potential platform for modelling in vitro bone marrow stem cell niches, elucidating interactions between cells, as well as a useful model for drug delivery studies. PMID:28616152

Fabrication and evaluation of novel zeolite membranes to control the neoplastic activity and anti-tumoral drug treatments in human breast cancer cells. Part 1: Synthesis and characterization of Pure Zeolite Membranes and Mixed Matrix Membranes for adhesion and growth of cancer cells.

PubMed

Tavolaro, Palmira; Martino, Guglielmo; Andò, Sebastiano; Tavolaro, Adalgisa

2016-12-01

Novel pure and hybrid zeolite membranes were prepared with appropriate different physicochemical characteristics such as frameworks, hydrophilicity, crystal size, chemical composition, acid-base properties (Point of Zero Charge, PZC) and surface morphology and used in inorganic cell/scaffold constructs. Because the control of cell interactions, as the adhesion, proliferation, remodelling and mobility, is important for differentiation and progression of tumors, this work focused on response of cancer cells adhered and grown on synthesized zeolite surfaces in order to study the influence of these scaffolds in controlled conditions. We have selected the MCF-7 and MDA-MB-231 human breast cancer cell line as model tumor cell lines. This study showed that all the zeolite membranes synthesized are excellent scaffolds because they are very selective materials to support the adhesion and growth of neoplastic cells. All zeolite scaffolds were characterized by FESEM, FTIR ATR, XRD, AFM, PZC and contact angle analyses. Cell adhesion, viability and morphology were measured by count, MTT assay and FESEM microphotography analysis, at various incubation times. Copyright © 2016. Published by Elsevier B.V.

Surface wettability of plasma SiOx:H nanocoating-induced endothelial cells' migration and the associated FAK-Rho GTPases signalling pathways

PubMed Central

Shen, Yang; Wang, Guixue; Huang, Xianliang; Zhang, Qin; Wu, Jiang; Tang, Chaojun; Yu, Qingsong; Liu, Xiaoheng

2012-01-01

Vascular endothelial cell (EC) adhesion and migration are essential processes in re-endothelialization of implanted biomaterials. There is no clear relationship and mechanism between EC adhesion and migration behaviour on surfaces with varying wettabilities. As model substrates, plasma SiOx:H nanocoatings with well-controlled surface wettability (with water contact angles in the range of 98.5 ± 2.3° to 26.3 ± 4.0°) were used in this study to investigate the effects of surface wettability on cell adhesion/migration and associated protein expressions in FAK-Rho GTPases signalling pathways. It was found that EC adhesion/migration showed opposite behaviour on the hydrophilic and hydrophobic surfaces (i.e. hydrophobic surfaces promoted EC migration but were anti-adhesions). The number of adherent ECs showed a maximum on hydrophilic surfaces, while cells adhered to hydrophobic surfaces exhibited a tendency for cell migration. The focal adhesion kinase (FAK) inhibitor targeting the Y-397 site of FAK could significantly inhibit cell adhesion/migration, suggesting that EC adhesion and migration on surfaces with different wettabilities involve (p)FAK and its downstream signalling pathways. Western blot results suggested that the FAK-Rho GTPases signalling pathways were correlative to EC migration on hydrophobic plasma SiOx:H surfaces, but uncertain to hydrophilic surfaces. This work demonstrated that surface wettability could induce cellular behaviours that were associated with different cellular signalling events. PMID:21715399

Differential effect on cell-mediated immunity in human volunteers after intake of different lactobacilli

PubMed Central

Rask, C; Adlerberth, I; Berggren, A; Ahrén, I L; Wold, A E

2013-01-01

Probiotics are live microorganisms which have beneficial effects on the host when ingested in adequate amounts. Probiotic bacteria may stimulate immune effector functions in a strain-specific manner. In this blind placebo-controlled trial, we investigated the effects on the immune system following daily intake of six different strains of lactobacilli or the Gram-negative bacterium Pseudomonas lundensis for 2 or 5 weeks. Blood lymphocyte subsets were quantified by fluorescence activated cell sorter and the expression of activation and memory markers was determined. The bacterial strains were also examined for their capacity to adhere to human intestinal cells and to be phagocytosed by human peripheral blood mononuclear cells. Intake of Lactobacillus plantarum strain 299v increased the expression of the activation marker CD25 (P = 0·01) on CD8+ T cells and the memory cell marker CD45RO on CD4+ T cells (P = 0·03), whereas intake of L. paracasei tended to expand the natural killer T (NK T) cell population (P = 0·06). The phagocytic activity of granulocytes was increased following intake of L. plantarum 299v, L. plantarum HEAL, L. paracasei or L. fermentum. In contrast, ingestion of L. rhamnosus decreased the expression of CD25 and CD45RO significantly within the CD4+ cell population. The observed immune effects after in-vivo administration of the probiotic bacteria could not be predicted by either their adherence capacity or the in-vitro-induced cytokine production. The stimulation of CD8+ T cells and NK T cells suggests that intake of probiotic bacteria may enhance the immune defence against, e.g. viral infections or tumours. PMID:23574328

Differential effect on cell-mediated immunity in human volunteers after intake of different lactobacilli.

PubMed

Rask, C; Adlerberth, I; Berggren, A; Ahrén, I L; Wold, A E

2013-05-01

Probiotics are live microorganisms which have beneficial effects on the host when ingested in adequate amounts. Probiotic bacteria may stimulate immune effector functions in a strain-specific manner. In this blind placebo-controlled trial, we investigated the effects on the immune system following daily intake of six different strains of lactobacilli or the Gram-negative bacterium Pseudomonas lundensis for 2 or 5 weeks. Blood lymphocyte subsets were quantified by fluorescence activated cell sorter and the expression of activation and memory markers was determined. The bacterial strains were also examined for their capacity to adhere to human intestinal cells and to be phagocytosed by human peripheral blood mononuclear cells. Intake of Lactobacillus plantarum strain 299v increased the expression of the activation marker CD25 (P = 0·01) on CD8(+) T cells and the memory cell marker CD45RO on CD4(+) T cells (P = 0·03), whereas intake of L. paracasei tended to expand the natural killer T (NK T) cell population (P = 0·06). The phagocytic activity of granulocytes was increased following intake of L. plantarum 299v, L. plantarum HEAL, L. paracasei or L. fermentum. In contrast, ingestion of L. rhamnosus decreased the expression of CD25 and CD45RO significantly within the CD4(+) cell population. The observed immune effects after in-vivo administration of the probiotic bacteria could not be predicted by either their adherence capacity or the in-vitro-induced cytokine production. The stimulation of CD8(+) T cells and NK T cells suggests that intake of probiotic bacteria may enhance the immune defence against, e.g. viral infections or tumours. © 2012 British Society for Immunology.

A Pilot Randomized Controlled Trial to Promote Immunosuppressant Adherence in Adult Kidney Transplant Recipients.

PubMed

Cukor, Daniel; Ver Halen, Nisha; Pencille, Melissa; Tedla, Fasika; Salifu, Moro

2017-01-01

Nonadherence to immunosuppressant medication is a prevalent practice among kidney transplant recipients and has been associated with increased risk for graft failure and economic burden. The aim of this pilot study was to test whether a culturally sensitive cognitive-behavioral adherence promotion program could significantly improve medication adherence to tacrolimus prescription as measured by telephone pill counts among kidney transplant recipients. Thirty-three adult transplant recipients were less than 98% adherent to tacrolimus prescription based on 3 telephone pill counts and were randomized either to the 2-session cognitive-behavioral adherence promotion program or to standard care. The curriculum was developed from an iterative process with transplant recipients into a 2-session group program that provided psychoeducation, addressed barriers to adherence, fostered motivation to improve adherence behavior, and discussed cultural messages on adherence behavior. The intervention group displayed significantly higher levels of adherence when compared to the control group (t = 2.2, p = 0.04) and. similarly, when the amount of change was compared between the groups, the intervention group showed more change than the control condition (F (22,1) = 12.005, p = 0.003). Tacrolimus trough concentration levels were used as a secondary measure of adherence and, while there were no significant between-group differences for mean trough concentration levels, the variability in the trough levels did significantly decrease over time indicating more consistent pill-taking behavior in the intervention group. There is preliminary support for the pilot program as a successful intervention in helping patients with their immunosuppressant medication. © 2016 S. Karger AG, Basel.

Retailer Adherence to Family Smoking Prevention and Tobacco Control Act, North Carolina, 2011

PubMed Central

Myers, Allison E.; D’Angelo, Heather; Ribisl, Kurt M.

2013-01-01

Introduction The Family Smoking Prevention and Tobacco Control Act regulates the sales and marketing of tobacco products in the United States; poor adherence by tobacco retailers may reduce the effectiveness of the Act’s provisions. The objectives of this study were 1) to assess whether and to which provisions retailers were adherent and 2) to examine differences in adherence by county, retailer neighborhood, and retailer characteristics. Methods We conducted multivariate analysis of tobacco retailers’ adherence to 12 point-of-sale provisions of the Tobacco Control Act in 3 North Carolina counties. We conducted observational audits of 324 retailers during 3 months in 2011 to assess adherence. We used logistic regression to assess associations between adherence to provisions and characteristics of each county, retailer neighborhood, and retailer. Results We found 15.7% of retailers did not adhere to at least 1 provision; 84.3% adhered to all provisions. The provisions most frequently violated were the ban on sales of cigarettes with modified-risk labels (eg, “light” cigarettes) (43 [13.3%] retailers nonadherent) and the ban on self-service for cigarettes and smokeless tobacco (6 [1.9%] retailers nonadherent). We found significant differences in rates of nonadherence by county and type of retailer. Pharmacies and drug stores were more than 3 times as likely as grocery stores to be nonadherent. Conclusion Most tobacco retailers have implemented regulatory changes without enforcement by the US Food and Drug Administration. Monitoring rates of adherence by store type and locale (eg, county) may help retailers comply with point-of-sale provisions. PMID:23557638

Effect of environmental stress on the ability of Listeria monocytogenes Scott A to attach to food contact surfaces.

PubMed

Smoot, L M; Pierson, M D

1998-10-01

Attachment of Listeria monocytogenes Scott A to Buna-N rubber and stainless steel under different temperature and pH conditions at the time of cell growth or at the time of attachment was investigated. All experiments were conducted using sterile phosphate buffer to avoid cell growth during exposure to the test surfaces. Numbers of attached cells increased with increasing attachment temperature (10 to 45 degrees C) and exposure time for both test surfaces. Maximum levels of attached cells were obtained when cell growth occurred at 30 degrees C. Downward, but not upward, shifts in the cell suspension holding temperature prior to attachment to Buna-N rubber resulted in reduced adhered cell populations. Maximum levels of adhered cells to Buna-N rubber were not affected by adjustments of the attachment medium pH between 4 and 9. However, after short contact times (i.e., less than 30 min), levels of attached cells were lower when attachment occurred under alkaline conditions. Growth pH was also found to affect the levels of adhered cell populations to Buna-N rubber. L. monocytogenes Scott A attached to stainless steel at higher levels for all temperature and pH parameters evaluated in this study.

Interfacing nanostructures to biological cells

DOEpatents

Chen, Xing; Bertozzi, Carolyn R.; Zettl, Alexander K.

2012-09-04

Disclosed herein are methods and materials by which nanostructures such as carbon nanotubes, nanorods, etc. are bound to lectins and/or polysaccharides and prepared for administration to cells. Also disclosed are complexes comprising glycosylated nanostructures, which bind selectively to cells expressing glycosylated surface molecules recognized by the lectin. Exemplified is a complex comprising a carbon nanotube functionalized with a lipid-like alkane, linked to a polymer bearing repeated .alpha.-N-acetylgalactosamine sugar groups. This complex is shown to selectively adhere to the surface of living cells, without toxicity. In the exemplified embodiment, adherence is mediated by a multivalent lectin, which binds both to the cells and the .alpha.-N-acetylgalactosamine groups on the nanostructure.

Impact of calcium signaling during infection of Neisseria meningitidis to human brain microvascular endothelial cells.

PubMed

Asmat, Tauseef M; Tenenbaum, Tobias; Jonsson, Ann-Beth; Schwerk, Christian; Schroten, Horst

2014-01-01

The pili and outer membrane proteins of Neisseria meningitidis (meningococci) facilitate bacterial adhesion and invasion into host cells. In this context expression of meningococcal PilC1 protein has been reported to play a crucial role. Intracellular calcium mobilization has been implicated as an important signaling event during internalization of several bacterial pathogens. Here we employed time lapse calcium-imaging and demonstrated that PilC1 of meningococci triggered a significant increase in cytoplasmic calcium in human brain microvascular endothelial cells, whereas PilC1-deficient meningococci could not initiate this signaling process. The increase in cytosolic calcium in response to PilC1-expressing meningococci was due to efflux of calcium from host intracellular stores as demonstrated by using 2-APB, which inhibits the release of calcium from the endoplasmic reticulum. Moreover, pre-treatment of host cells with U73122 (phospholipase C inhibitor) abolished the cytosolic calcium increase caused by PilC1-expressing meningococci demonstrating that active phospholipase C (PLC) is required to induce calcium transients in host cells. Furthermore, the role of cytosolic calcium on meningococcal adherence and internalization was documented by gentamicin protection assay and double immunofluorescence (DIF) staining. Results indicated that chelation of intracellular calcium by using BAPTA-AM significantly impaired PilC1-mediated meningococcal adherence to and invasion into host endothelial cells. However, buffering of extracellular calcium by BAPTA or EGTA demonstrated no significant effect on meningococcal adherence to and invasion into host cells. Taken together, these results indicate that meningococci induce calcium release from intracellular stores of host endothelial cells via PilC1 and cytoplasmic calcium concentrations play a critical role during PilC1 mediated meningococcal adherence to and subsequent invasion into host endothelial cells.

Enhanced antiadhesive properties of chitosan/hyaluronic acid polyelectrolyte multilayers driven by thermal annealing: Low adherence for mammalian cells and selective decrease in adhesion for Gram-positive bacteria.

PubMed

Muzzio, Nicolás E; Pasquale, Miguel A; Diamanti, Eleftheria; Gregurec, Danijela; Moro, Marta Martinez; Azzaroni, Omar; Moya, Sergio E

2017-11-01

The development of antifouling coatings with restricted cell and bacteria adherence is fundamental for many biomedical applications. A strategy for the fabrication of antifouling coatings based on the layer-by-layer assembly and thermal annealing is presented. Polyelectrolyte multilayers (PEMs) assembled from chitosan and hyaluronic acid were thermally annealed in an oven at 37°C for 72h. The effect of annealing on the PEM properties and topography was studied by atomic force microscopy, ζ-potential, circular dichroism and contact angle measurements. Cell adherence on PEMs before and after annealing was evaluated by measuring the cell spreading area and aspect ratio for the A549 epithelial, BHK kidney fibroblast, C2C12 myoblast and MC-3T3-E1 osteoblast cell lines. Chitosan/hyaluronic acid PEMs show a low cell adherence that decreases with the thermal annealing, as observed from the reduction in the average cell spreading area and more rounded cell morphology. The adhesion of S. aureus (Gram-positive) and E. coli (Gram-negative) bacteria strains was quantified by optical microscopy, counting the number of colony-forming units and measuring the light scattering of bacteria suspension after detachment from the PEM surface. A 20% decrease in bacteria adhesion was selectively observed in the S. aureus strain after annealing. The changes in mammalian cell and bacteria adhesion correlate with the changes in topography of the chitosan/hyaluronic PEMs from a rough fibrillar 3D structure to a smoother and planar surface after thermal annealing. Copyright © 2017. Published by Elsevier B.V.

Engagement with a Text-Messaging Intervention Improves Adherence in Adolescents with Type 1 Diabetes: Brief Report.

PubMed

Zhang, Shuodan; Hamburger, Emily; Kahanda, Sachini; Lyttle, Morgan; Williams, Rodayne; Jaser, Sarah S

2018-05-01

Adherence to diabetes management is a challenge for adolescents with type 1 diabetes (T1D). Positive psychology interventions have improved adherence to treatment recommendations in adults with chronic health conditions but have not been widely tested in pediatric populations. We hypothesized that higher engagement with a text-messaging intervention to promote positive affect would increase the effects on diabetes management among adolescents with T1D. Adolescents with T1D (n = 48) and their caregivers were randomized to either an attention control condition or a novel positive psychology intervention delivered through personalized automated text messaging. We examined rates of engagement (percent response to text messages) in relation to demographic factors, and we explored the effect of engagement in relation to adherence and glycemic control. Adolescent engagement was good (mean response rate of 76%) over the 8-week intervention. Engagement was related to adolescents' gender, race, baseline glycemic control, and blood glucose monitoring, but not to treatment type (pump vs. injection), diabetes duration, age, or household income. There was a significant effect of level of engagement on better caregiver-reported adherence, but adolescents' engagement was not related to self-reported adherence or glycemic control. These results indicate feasibility and initial efficacy of using automated text-messaging to deliver an intervention aimed at promoting adherence in adolescents with T1D.

Coeliac disease in adolescence: Coping strategies and personality factors affecting compliance with gluten-free diet.

PubMed

Wagner, Gudrun; Zeiler, Michael; Grylli, Vasileia; Berger, Gabriele; Huber, Wolf-Dietrich; Woeber, Christian; Rhind, Charlotte; Karwautz, Andreas

2016-06-01

Patients suffering from a chronic condition such as coeliac disease (CD) need to develop coping strategies in order to preserve emotional balance and psychosocial functioning while adhering to their obligatory life-long gluten free diet (GFD). However, this can be particularly challenging for adolescents and may lead to dietary transgressions. Little is currently known about the influence of coping strategies and personality factors on dietary compliance. This study aims to explore these factors for the first time in adolescents with biopsy-proven CD. We included 281 adolescents with CD and 95 healthy controls. We classified patients according to their GFD adherence status (adherent vs. non-adherent) and assessed coping strategies using the KIDCOPE and personality traits using the Junior-Temperament and Character Inventory (J-TCI). Adolescents with CD adherent to GFD used less emotional regulation and distraction as coping strategies than non-adherent patients. In terms of personality traits, adherent patients differed from non-adherent patients with respect to temperament, but not with respect to character, showing lower scores in novelty seeking, impulsivity and rule transgressions and higher scores in eagerness with work and perfectionism compared to non-adherent patients. No differences were found between healthy controls and adherent CD patients across these personality traits. Coping strategies and personality traits differ in adolescent patients with CD adherent to GFD from those not adherent, and may therefore relate to risk or protective factors in adherence. Targeting coping and temperament using psychological interventions may therefore be beneficial to support adolescents with CD and optimise their adherence to GFD. Copyright © 2016 Elsevier Ltd. All rights reserved.

Virulence properties of asymptomatic bacteriuria Escherichia coli.

PubMed

Mabbett, Amanda N; Ulett, Glen C; Watts, Rebecca E; Tree, Jai J; Totsika, Makrina; Ong, Cheryl-lynn Y; Wood, Jacqueline M; Monaghan, Wayne; Looke, David F; Nimmo, Graeme R; Svanborg, Catharina; Schembri, Mark A

2009-01-01

In asymptomatic bacteriuria (ABU), bacteria colonize the urinary tract without provoking symptoms. Here, we compared the virulence properties of a collection of ABU Escherichia coli strains to cystitis and pyelonephritis strains. Specific urinary tract infection (UTI)-associated virulence genes, hemagglutination characteristics, siderophore production, hemolysis, biofilm formation, and the ability of strains to adhere to and induce cytokine responses in epithelial cells were analyzed. ABU strains were phylogenetically related to strains that cause symptomatic UTI. However, the virulence properties of the ABU strains were variable and dependent on a combination of genotypic and phenotypic factors. Most ABU strains adhered poorly to epithelial cells; however, we also identified a subgroup of strongly adherent strains that were unable to stimulate an epithelial cell IL-6 cytokine response. Poor immune activation may represent one mechanism whereby ABU E. coli evade immune detection after the establishment of bacteriuria.

Influence of irrigation regimens on the adherence of Enterococcus faecalis to root canal dentin.

PubMed

Kishen, Anil; Sum, Chee-Peng; Mathew, Shibi; Lim, Chwee-Teck

2008-07-01

Enterococcus faecalis is frequently associated with post-treatment endodontic infections. Because adherence of bacteria to a substrate is the earliest stage in biofilm formation, eliciting the factors that links adherence of this bacterium to dentin would help in understanding its association with treatment-failed root canals. This investigation aimed to study the effects of endodontic irrigants on the adherence of E. faecalis to dentin. The bacteria adherence assay was conducted by using fluorescence microscopy, and the adhesion force was measured by using atomic force microscopy. There were significant increases in adherence and adhesion force after irrigation of dentin with ethylenediaminetetraacetic acid (EDTA), whereas sodium hypochlorite (NaOCl) reduced it. With the use of chlorhexidine (CHX), the force of adhesion increased, but the adherence assay showed a reduction in the number of adhering bacteria. The irrigation regimen of EDTA, NaOCl, and CHX resulted in the least number of adhering E. faecalis cells. This study highlighted that chemicals that alter the physicochemical properties of dentin will influence the nature of adherence, adhesion force, and subsequent biofilm formation of E. faecalis to dentin.

Controlling Cell Function with Geometry

NASA Astrophysics Data System (ADS)

Mrksich, Milan

2012-02-01

This presentation will describe the use of patterned substrates to control cell shape with examples that illustrate the ways in which cell shape can regulate cell function. Most cells are adherent and must attach to and spread on a surface in order to survive, proliferate and function. In tissue, this surface is the extracellular matrix (ECM), an insoluble scaffold formed by the assembly of several large proteins---including fibronectin, the laminins and collagens and others---but in the laboratory, the surface is prepared by adsorbing protein to glass slides. To pattern cells, gold-coated slides are patterned with microcontact printing to create geometric features that promote cell attachment and that are surrounded by inert regions. Cells attach to these substrates and spread to adopt the shape defined by the underlying pattern and remain stable in culture for several days. Examples will be described that used a series of shapes to reveal the relationship between the shape of the cell and the structure of its cytoskeleton. These geometric cues were used to control cell polarity and the tension, or contractility, present in the cytoskeleton. These rules were further used to control the shapes of mesenchymal stem cells and in turn to control the differentiation of these cells into specialized cell types. For example, stem cells that were patterned into a ``star'' shape preferentially differentiated into bone cells whereas those that were patterned into a ``flower'' shape preferred a fat cell fate. These influences of shape on differentiation depend on the mechanical properties of the cytoskeleton. These examples, and others, reveal that shape is an important cue that informs cell function and that can be combined with the more common soluble cues to direct and study cell function.

Lymphocyte responses to phytohaemagglutinin: age-related effects.

PubMed Central

Fernandez, L A; MacSween, J M; Langley, G R

1976-01-01

Cell-mediated immunity is depressed in elderly individuals compared to young individuals, and lymphocytes from elderly individuals have been reported to have impaired lymphocyte responsiveness to stimulation by PHA after 4 days of culture. We have confirmed this observation. However, after 8 days of culture, the lymphocyte responses were greater in elderly normal individuals than in young normal individuals. Responses of lymphocytes from young individuals decreased with time from 4 to 8 days in culture, while there were increased responses with time when lymphocytes from elderly individuals were studied. When adherent cells from lymphocytes of young individuals were removed by passage through protein-coated Degalan-bead columns, the lymphocyte responses to PHA were significantly increased at 8 days. Passage of lymphocytes from elderly individuals through coated Degalan bead columns did not alter the lymphocyte responses. Removal of macrophages from the mononuclear cells obtained from young individuals did not result in increased lymphocyte responses to PHA after 8 days in culture. Removal of adherent cells appeared to have the same effect regardless of the efficiency of removing B cells. The adherent cells removed by the protein coated columns, therefore, appear to be nonphagocytic mononuclear cells which are not B lymphocytes. PMID:1086285

Isolation and characterisation of cancer stem cells from canine osteosarcoma.

PubMed

Wilson, H; Huelsmeyer, M; Chun, R; Young, K M; Friedrichs, K; Argyle, D J

2008-01-01

There is increasing evidence that cancer is a stem cell disease. This study sought to isolate and characterise cancer stem cells from canine osteosarcoma. One human and three canine cell lines were cultured in non-adherent culture conditions using serum-starved, semi-solid media. Primitive sarcosphere colonies from all cell lines were identified under these conditions and were characterised using molecular and cytochemical techniques for embryonic stem cell markers. Expression of the embryonic stem cell-associated genes Nanog, Oct4 and STAT3 indicated a primitive phenotype. Sarcospheres could be reproduced consistently when passaged multiple times and produced adherent cell cultures when returned to normal growth conditions. Similarities between human and canine osteosarcoma cell lines add credence to the potential of the dog as a model for human disease.

Toxicity Minimized Cryoprotectant Addition and Removal Procedures for Adherent Endothelial Cells

PubMed Central

Davidson, Allyson Fry; Glasscock, Cameron; McClanahan, Danielle R.; Benson, James D.; Higgins, Adam Z.

2015-01-01

Ice-free cryopreservation, known as vitrification, is an appealing approach for banking of adherent cells and tissues because it prevents dissociation and morphological damage that may result from ice crystal formation. However, current vitrification methods are often limited by the cytotoxicity of the concentrated cryoprotective agent (CPA) solutions that are required to suppress ice formation. Recently, we described a mathematical strategy for identifying minimally toxic CPA equilibration procedures based on the minimization of a toxicity cost function. Here we provide direct experimental support for the feasibility of these methods when applied to adherent endothelial cells. We first developed a concentration- and temperature-dependent toxicity cost function by exposing the cells to a range of glycerol concentrations at 21°C and 37°C, and fitting the resulting viability data to a first order cell death model. This cost function was then numerically minimized in our state constrained optimization routine to determine addition and removal procedures for 17 molal (mol/kg water) glycerol solutions. Using these predicted optimal procedures, we obtained 81% recovery after exposure to vitrification solutions, as well as successful vitrification with the relatively slow cooling and warming rates of 50°C/min and 130°C/min. In comparison, conventional multistep CPA equilibration procedures resulted in much lower cell yields of about 10%. Our results demonstrate the potential for rational design of minimally toxic vitrification procedures and pave the way for extension of our optimization approach to other adherent cell types as well as more complex systems such as tissues and organs. PMID:26605546

Impact of a telephonic outreach program on medication adherence in Medicare Advantage Prescription Drug (MAPD) plan beneficiaries.

PubMed

Park, Haesuk; Adeyemi, Ayoade; Wang, Wei; Roane, Teresa E

To determine the impact of a telephone call reminder program provided by a campus-based medication therapy management call center on medication adherence in Medicare Advantage Part D (MAPD) beneficiaries with hypertension. The reminder call services were offered to eligible MAPD beneficiaries, and they included a live interactive conversation with patients to assess the use of their medications. This study used a quasi-experimental design for comparing the change in medication adherence between the intervention and matched control groups. Adherence, defined by proportion of days covered (PDC), was measured using incurred medication claims 6 months before and after the adherence program was implemented. A difference-in-differences approach with propensity score matching was used. After propensity score matching, paired samples included 563 patients in each of the intervention and control groups. The mean PDC (standard deviation) increased significantly during postintervention period by 17.3% (33.6; P <0.001) and 13.8% (32.3; P <0.001) for the intervention and the control groups, respectively; the greater difference-in-differences increase of 3.5% (36.3) in the intervention group over the control group was statistically significant (P = 0.022). A generalized estimating equation model adjusting for covariates further confirmed that the reminder call group had a significant increase in pre-post PDC (P = 0.021), as compared with the control group. Antihypertensive medication adherence increased in both reminder call and control groups, but the increase was significantly higher in the intervention group. A telephonic outreach program was effective in improving antihypertensive medication adherence in MAPD beneficiaries. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Patient-Oncologist Alliance, Psychosocial Well-Being, and Treatment Adherence Among Young Adults With Advanced Cancer

PubMed Central

Trevino, Kelly M.; Fasciano, Karen; Prigerson, Holly G.

2013-01-01

Purpose Patients who develop a strong alliance with their health care providers have been shown to have higher levels of psychosocial well-being and rates of treatment adherence. Young adults with cancer have lower levels of psychosocial well-being and treatment adherence relative to patients with cancer in other age groups. This study sought to evaluate the relationships between the patient-oncologist alliance, psychosocial well-being, and treatment adherence in young adults with advanced cancer. Patients and Methods Ninety-five young adults (age 20 to 40 years) with advanced cancer were administered measures of alliance, psychosocial well-being, willingness to adhere to treatment, and treatment adherence. Relationships between alliance and psychosocial well-being were examined bivariately. Multiple linear regression models examined the relationship between alliance and adherence, controlling for confounding influences (eg, psychosocial well-being). Results Alliance was significantly (P ≤ .01) and positively associated with greater perceived social support and less severe illness-related grief. After controlling for significant confounding influences (ie, metastases, appraised support, and grief), alliance remained significantly (P ≤ .01) associated with greater willingness to adhere to treatment and greater adherence to oral medication. Conclusion By developing a strong alliance, oncologists may enhance psychosocial well-being and increase treatment adherence in young adult patients with advanced cancer. PMID:23530105

Phagocytic cell function in active brucellosis.

PubMed Central

Ocon, P; Reguera, J M; Morata, P; Juarez, C; Alonso, A; Colmenero, J D

1994-01-01

In this study, we analyzed phagocytic cell function in 51 patients with active brucellosis and its relationship with different clinical, serological, and evolutionary variables. A control group was made up of 30 blood donors of similar geographic extraction, age, and sex, with no previous history of brucellosis or known exposure ot the infection or specific antibodies. The investigations were carried out at the time of diagnosis, at the conclusion of treatment, and after 6 months of follow-up. Polymorphonuclear leukocyte adherence and nitroblue tetrazolium reduction in response to Brucella antigen were significantly increased in the patients at the time of diagnosis with respect to the control group. In contrast, chemotaxis in response to Brucella antigen and phagocytosis were significantly reduced in the patients with respect to the control group. The alterations in phagocytic cell function were greater in patients with bacteremia, with focal forms of the disease, or with a longer diagnostic delay. Most of these initial alterations tended to normalize with treatment, indicating their transient character. PMID:8112863

ROCK inhibition promotes microtentacles that enhance reattachment of breast cancer cells

PubMed Central

Bhandary, Lekhana; Whipple, Rebecca A.; Vitolo, Michele I.; Charpentier, Monica S.; Boggs, Amanda E.; Chakrabarti, Kristi R.; Thompson, Keyata N.; Martin, Stuart S.

2015-01-01

The presence of circulating tumor cells (CTCs) in blood predicts poor patient outcome and CTC frequency is correlated with higher risk of metastasis. Recently discovered, novel microtubule-based structures, microtentacles, can enhance reattachment of CTCs to the vasculature. Microtentacles are highly dynamic membrane protrusions formed in detached cells and occur when physical forces generated by the outwardly expanding microtubules overcome the contractile force of the actin cortex. Rho-associated kinase (ROCK) is a major regulator of actomyosin contractility and Rho/ROCK over-activation is implicated in tumor metastasis. ROCK inhibitors are gaining popularity as potential cancer therapeutics based on their success in reducing adherent tumor cell migration and invasion. However, the effect of ROCK inhibition on detached cells in circulation is largely unknown. In this study, we use breast tumor cells in suspension to mimic detached CTCs and show that destabilizing the actin cortex through ROCK inhibition in suspended cells promotes the formation of microtentacles and enhances reattachment of cells from suspension. Conversely, increasing actomyosin contraction by Rho over-activation reduces microtentacle frequency and reattachment. Although ROCK inhibitors may be effective in reducing adherent tumor cell behavior, our results indicate that they could inadvertently increase metastatic potential of non-adherent CTCs by increasing their reattachment efficacy. PMID:25749040

Synergistic Integration of Mesenchymal Stem Cells and Hydrostatic Pressure in the Expansion and Maintenance of Human Hematopoietic/Progenitor Cells

PubMed Central

2018-01-01

Ex vivo expansion of hematopoietic stem/progenitor cell (HSPC) has been investigated to improve the clinical outcome of HSPC transplantation. However, ex vivo expansion of HSPCs still faces a major obstacle in that HPSCs tend to differentiate when proliferating. Here, we cocultured HSPCs with mesenchymal stem cells (MSCs) and divided the HSPCs into two fractions according to whether they came into adherent to MSCs or not. Additionally, we used hydrostatic pressure (HP) to mimic the physical conditions in vivo. Even nonadherent cells expanded to yield a significantly larger number of total nucleated cells (TNCs), adherent cells maintained the HSPC phenotype (CD34+, CD34+CD38−, and CD133+CD38−) to a greater extent than nonadherent cells and had superior clonogenic potential. Moreover, applying HP significantly increased the number of TNCs, the frequency of the immature HSPC phenotype, and the clonogenic potential. Furthermore, the genetic markers for the HSPC niche were significantly increased under HP. Our data suggest that the nonadherent fraction is the predominant site of HSPC expansion, whereas the adherent fraction seems to mimic the HSPC niche for immature cells. Moreover, HP has a synergistic effect on expansion and functional maintenance. This first study utilizing HP has a potential of designing clinically applicable expansion systems. PMID:29681947

Fibronectin regulates the activation of THP-1 cells by TGF-beta1.

PubMed

Wang, A C; Fu, L

2001-03-01

To determine how fibronectin regulates the immunomodulatory effects of transforming growth factor (TGF)-beta on THP-1 cells. THP-1 monocytic cell line. THP-1 cells were primed for 48 h in the presence or absence of 250 pM TGF-beta1. Assays or assessments carried out, together with statistical test applied. We found that adherence to fibronectin dramatically modulates the effects of TGF-beta1 on the human monocytic cell line THP-1. TGF-beta did not significantly affect constitutive interleukin (IL)-8 secretion or IL-1beta-induced IL-8 secretion from suspended cells. In contrast, TGF-beta stimulated IL-8 secretion as well as augmented IL-1beta-induced IL-8 secretion from adherent cells. The differential effects of TGF-beta1 on IL-8 secretion from suspended and adherent cells could not be explained by differences in IL-1 receptor antagonist production. The effects of fibronectin on TGF-beta1 induced IL-8 secretion from THP-1 cells were mimicked by adhesion to immobilized anti-a4beta1 integrin antibody and to a fibronectin fragment containing the CS-1 domain. These results indicate that alpha4beta1-mediated adhesion to fibronectin may play a key role during inflammation by profoundly influencing the effects of TGF-beta1 on monocytes.

Biological length scale topography enhances cell-substratum adhesion of human corneal epithelial cells

PubMed Central

Karuri, Nancy W.; Liliensiek, Sara; Teixeira, Ana I.; Abrams, George; Campbell, Sean; Nealey, Paul F.; Murphy, Christopher J.

2006-01-01

Summary The basement membrane possesses a rich 3-dimensional nanoscale topography that provides a physical stimulus, which may modulate cell-substratum adhesion. We have investigated the strength of cell-substratum adhesion on nanoscale topographic features of a similar scale to that of the native basement membrane. SV40 human corneal epithelial cells were challenged by well-defined fluid shear, and cell detachment was monitored. We created silicon substrata with uniform grooves and ridges having pitch dimensions of 400-4000 nm using X-ray lithography. F-actin labeling of cells that had been incubated for 24 hours revealed that the percentage of aligned and elongated cells on the patterned surfaces was the same regardless of pitch dimension. In contrast, at the highest fluid shear, a biphasic trend in cell adhesion was observed with cells being most adherent to the smaller features. The 400 nm pitch had the highest percentage of adherent cells at the end of the adhesion assay. The effect of substratum topography was lost for the largest features evaluated, the 4000 nm pitch. Qualitative and quantitative analyses of the cells during and after flow indicated that the aligned and elongated cells on the 400 nm pitch were more tightly adhered compared to aligned cells on the larger patterns. Selected experiments with primary cultured human corneal epithelial cells produced similar results to the SV40 human corneal epithelial cells. These findings have relevance to interpretation of cell-biomaterial interactions in tissue engineering and prosthetic design. PMID:15226393

Mapping the dynamics of force transduction at cell–cell junctions of epithelial clusters

PubMed Central

Ng, Mei Rosa; Besser, Achim; Brugge, Joan S; Danuser, Gaudenz

2014-01-01

Force transduction at cell-cell adhesions regulates tissue development, maintenance and adaptation. We developed computational and experimental approaches to quantify, with both sub-cellular and multi-cellular resolution, the dynamics of force transmission in cell clusters. Applying this technology to spontaneously-forming adherent epithelial cell clusters, we found that basal force fluctuations were coupled to E-cadherin localization at the level of individual cell-cell junctions. At the multi-cellular scale, cell-cell force exchange depended on the cell position within a cluster, and was adaptive to reconfigurations due to cell divisions or positional rearrangements. Importantly, force transmission through a cell required coordinated modulation of cell-matrix adhesion and actomyosin contractility in the cell and its neighbors. These data provide insights into mechanisms that could control mechanical stress homeostasis in dynamic epithelial tissues, and highlight our methods as a resource for the study of mechanotransduction in cell-cell adhesions. DOI: http://dx.doi.org/10.7554/eLife.03282.001 PMID:25479385

Cell phone short messaging service (SMS) for HIV/AIDS in South Africa: a literature review.

PubMed

Mukund Bahadur, Khatry-Chhetry; Murray, Peter J

2010-01-01

The HIV/AIDS pandemic is one of the most serious threats to global health. HIV/AIDS is a chronic illness, requiring patient empowerment to enhance adherence to treatment regimes if it is to be managed effectively. While healthcare costs are rising, people still have expectations of high-quality care. This literature review-based study explored the use of cell phone (mobile phone) short messaging services (SMS) in health care, in particular for HIV/AIDS in South Africa. From an initial corpus of 212 papers, 28 were reviewed. The main findings include that SMS can improve service delivery through appointment reminders and improve communication between healthcare workers. It improves diagnosis, prevention, treatment and rehabilitation by supporting adherence to medication, and monitoring illness and medical interventions. SMS is useful in public health programmes, such as contact tracing and partner notification, therefore playing an important role in control of HIV/AIDS. As South Africa has one of the highest uptakes and demographic distributions of cellular technology in the world, SMS is feasible as a tool to deliver quality health care with low cost.

Rapid Prototyping of Polymeric Nanopillars by 3D Direct Laser Writing for Controlling Cell Behavior.

PubMed

Buch-Månson, Nina; Spangenberg, Arnaud; Gomez, Laura Piedad Chia; Malval, Jean-Pierre; Soppera, Olivier; Martinez, Karen L

2017-08-23

Mammalian cells have been widely shown to respond to nano- and microtopography that mimics the extracellular matrix. Synthetic nano- and micron-sized structures are therefore of great interest in the field of tissue engineering, where polymers are particularly attractive due to excellent biocompatibility and versatile fabrication methods. Ordered arrays of polymeric pillars provide a controlled topographical environment to study and manipulate cells, but processing methods are typically either optimized for the nano- or microscale. Here, we demonstrate polymeric nanopillar (NP) fabrication using 3D direct laser writing (3D DLW), which offers a rapid prototyping across both size regimes. The NPs are interfaced with NIH3T3 cells and the effect of tuning geometrical parameters of the NP array is investigated. Cells are found to adhere on a wide range of geometries, but the interface depends on NP density and length. The Cell Interface with Nanostructure Arrays (CINA) model is successfully extended to predict the type of interface formed on different NP geometries, which is found to correlate with the efficiency of cell alignment along the NPs. The combination of the CINA model with the highly versatile 3D DLW fabrication thus holds the promise of improved design of polymeric NP arrays for controlling cell growth.

Epigenetic regulation of integrin-linked kinase expression depending on adhesion of gastric carcinoma cells.

PubMed

Kim, Yong-Bae; Lee, Sung-Yul; Ye, Sang-Kyu; Lee, Jung Weon

2007-02-01

Cell adhesion to the extracellular matrix (ECM) regulates gene expressions in diverse dynamic environments. However, the manner in which gene expressions are regulated by extracellular cues is largely unknown. In this study, suspended gastric carcinoma cells showed higher basal and transforming growth factor-beta1 (TGFbeta1)-mediated acetylations of histone 3 (H3) and Lys(9) of H3 and levels of integrin-linked kinase (ILK) mRNA and protein than did fibronectin-adherent cells did. Moreover, the insignificant acetylation and ILK expression in adherent cells were recovered by alterations of integrin signaling and actin organization, indicating a connection between cytoplasmic and nuclear changes. Higher acetylations in suspended cells were correlated with associations between Smad4, p300/CBP, and Lys(9)-acetylated H3. Meanwhile, adherent cells showed more associations between HDAC3, Ski, and MeCP2. Chromatin immunoprecipitations with anti-acetylated H3, Lys(9)-acetylated H3, or p300/CBP antibody resulted in more coprecipitated ILK promoter, correlated with enhanced ILK mRNA and protein levels, in suspended cells. Moreover, ILK expression inversely regulated cell adhesion to ECM proteins, and its overexpression enhanced cell growth in soft agar. These observations indicate that cell adhesion and/or its related molecular basis regulate epigenetic mechanisms leading to a loss of ILK transcription, which in turn regulates cell adhesion property in a feedback linkage.

Adherence to hepatitis A virus vaccination in HIV-infected men who have sex with men.

PubMed

Kourkounti, Sofia; Paparizos, Vassilios; Leuow, Kirsten; Paparizou, Eleni; Antoniou, Christina

2015-10-01

Although vaccination against hepatitis A virus (HAV) is essential for human immunodeficiency virus (HIV)-infected patients, the uptake of HAV vaccine is reported to be very low. From 2007 to 2012, 912 HIV-infected men in Athens, Greece were screened for exposure to HAV. Two doses of an HAV vaccine were recommended to 569 eligible patients. Reminder cards with scheduled vaccination visits were given to each patient. Among eligible patients, 62.2% (354/569) received both doses. Patients who were fully vaccinated compared with non-adherent patients were natives, older, had undetectable HIV viral load, higher CD4 T cell counts and lower nadir CD4 T cell counts. Multivariate logistic regression revealed that the patient's country of origin (p = 0.024; OR = 2.712; 95% CI, 1.139-6.457), CD4 T cell count (p < 0.001) and nadir CD4 T cell count (p < 0.001) were factors directly associated with adherence. In conclusion, adherence to HAV vaccination was better than in previously published data. Because many of the factors related to vaccination completion are parameters of HIV infection, it appears that physician interest in HIV care and vaccination planning is crucial to enhancing vaccine uptake. © The Author(s) 2015.

Efficacy and safety of a multifactor intervention to improve therapeutic adherence in patients with chronic obstructive pulmonary disease (COPD): protocol for the ICEPOC study.

PubMed

Barnestein-Fonseca, Pilar; Leiva-Fernández, José; Vidal-España, Francisca; García-Ruiz, Antonio; Prados-Torres, Daniel; Leiva-Fernández, Francisca

2011-02-14

Low therapeutic adherence to medication is very common. Clinical effectiveness is related to dose rate and route of administration and so poor therapeutic adherence can reduce the clinical benefit of treatment. The therapeutic adherence of patients with chronic obstructive pulmonary disease (COPD) is extremely poor according to most studies. The research about COPD adherence has mainly focussed on quantifying its effect, and few studies have researched factors that affect non-adherence. Our study will evaluate the effectiveness of a multifactor intervention to improve the therapeutic adherence of COPD patients. A randomized controlled clinical trial with 140 COPD diagnosed patients selected by a non-probabilistic method of sampling. Subjects will be randomly allocated into two groups, using the block randomization technique. Every patient in each group will be visited four times during the year of the study. Motivational aspects related to adherence (beliefs and behaviour): group and individual interviews; cognitive aspects: information about illness; skills: inhaled technique training. Reinforcement of the cognitive-emotional aspects and inhaled technique training will be carried out in all visits of the intervention group. Adherence to a prescribed treatment involves a behavioural change. Cognitive, emotional and motivational aspects influence this change and so we consider the best intervention procedure to improve adherence would be a cognitive and emotional strategy which could be applied in daily clinical practice. Our hypothesis is that the application of a multifactor intervention (COPD information, dose reminders and reinforcing audiovisual material, motivational aspects and inhalation technique training) to COPD patients taking inhaled treatment will give a 25% increase in the number of patients showing therapeutic adherence in this group compared to the control group.We will evaluate the effectiveness of this multifactor intervention on patient adherence to inhaled drugs considering that it will be right and feasible to the clinical practice context. Current Controlled Trials ISRCTN18841601.

Syndecan-4 Phosphorylation Is a Control Point for Integrin Recycling

PubMed Central

Morgan, Mark R.; Hamidi, Hellyeh; Bass, Mark D.; Warwood, Stacey; Ballestrem, Christoph; Humphries, Martin J.

2013-01-01

Summary Precise spatiotemporal coordination of integrin adhesion complex dynamics is essential for efficient cell migration. For cells adherent to fibronectin, differential engagement of α5β1 and αVβ3 integrins is used to elicit changes in adhesion complex stability, mechanosensation, matrix assembly, and migration, but the mechanisms responsible for receptor regulation have remained largely obscure. We identify phosphorylation of the membrane-intercalated proteoglycan syndecan-4 as an essential switch controlling integrin recycling. Src phosphorylates syndecan-4 and, by driving syntenin binding, leads to suppression of Arf6 activity and recycling of αVβ3 to the plasma membrane at the expense of α5β1. The resultant elevation in αVβ3 engagement promotes stabilization of focal adhesions. Conversely, abrogation of syndecan-4 phosphorylation drives surface expression of α5β1, destabilizes adhesion complexes, and disrupts cell migration. These data identify the dynamic spatiotemporal regulation of Src-mediated syndecan-4 phosphorylation as an essential switch controlling integrin trafficking and adhesion dynamics to promote efficient cell migration. PMID:23453597

Computerized counseling reduces HIV-1 viral load and sexual transmission risk: findings from a randomized controlled trial.

PubMed

Kurth, Ann E; Spielberg, Freya; Cleland, Charles M; Lambdin, Barrot; Bangsberg, David R; Frick, Pamela A; Severynen, Anneleen O; Clausen, Marc; Norman, Robert G; Lockhart, David; Simoni, Jane M; Holmes, King K

2014-04-15

Evaluate a computerized intervention supporting antiretroviral therapy (ART) adherence and HIV transmission prevention. Longitudinal randomized controlled trial. An academic HIV clinic and a community-based organization in Seattle. In a total of 240 HIV-positive adults on ART, 209 completed 9-month follow-up (87% retention). Randomization to computerized counseling or assessment only, 4 sessions over 9 months. HIV-1 viral suppression, and self-reported ART adherence and transmission risks, compared using generalized estimating equations. Overall, intervention participants had reduced viral load: mean 0.17 log10 decline, versus 0.13 increase in controls, P = 0.053, and significant difference in ART adherence baseline to 9 months (P = 0.046). Their sexual transmission risk behaviors decreased (odds ratio = 0.55, P = 0.020), a reduction not seen among controls (odds ratio = 1.1, P = 0.664), and a significant difference in change (P = 0.040). Intervention effect was driven by those most in need; among those with detectable virus at baseline (>30 copies/mL, n = 89), intervention effect was mean 0.60 log10 viral load decline versus 0.15 increase in controls, P = 0.034. ART adherence at the final follow-up was 13 points higher among intervention participants versus controls, P = 0.038. Computerized counseling is promising for integrated ART adherence and safer sex, especially for individuals with problems in these areas. This is the first intervention to report improved ART adherence, viral suppression, and reduced secondary sexual transmission risk behavior.

IL-27 regulates the adherence, proliferation, and migration of MSCs and enhances their regulatory effects on Th1 and Th2 subset generations.

PubMed

Xu, Fenghuang; Yi, Junzhu; Wang, Zhuoya; Hu, Yejia; Han, Chunlei; Xue, Qun; Zhang, Xueguang; Luan, Xiying

2017-08-01

Interleukin 27 (IL-27) regulates T cell function and is involved in inflammation. It has been reported that human placenta-derived mesenchymal stromal cells (hPMSCs) can inhibit T cell responses and attenuate inflammation reactions. However, it is unclear whether IL-27 can regulate hPMSC function. Here, we examined the effects of IL-27 upon adherence, migration, and proliferation as well as the immunomodulatory effects of hPMSCs. The results show that IL-27 receptor α chain (IL-27Rα) is expressed in hPMSCs. IL-27 at 30 ng/ml inhibited hPMSC adherence and proliferation, while the migration of hPMSCs was promoted with IL-27 at doses of 20 or 30 ng/ml, as determined with use of real-time cell analysis (RTCA). Moreover, IL-27 promoted regulatory effects of hPMSCs through enhancing Th2 and suppressing Th1 subset generation from activated T cells in human peripheral blood. IL-27 also enhanced the ability of hPMSCs to secrete IL-10 from CD4 + T cells through increased expression levels of the programmed death ligand 1 (PDL1) in hPMSCs via the Janus kinase (JAK)/signal transducer and activator of transcription 1 (STAT1) signaling pathway. In conclusion, IL-27 has significant modulatory effects on adherence, proliferation, and migration of hPMSCs. IL-27 increased PDL1 expression levels in hPMSCs via the JAK/STAT1 pathway, which then enhanced the regulatory effects of hPMSCs upon Th1 and Th2 cell generations and IL-10 secretion from CD4 + T cells.

Monitoring attentional style and medical regimen adherence in hemodialysis patients.

PubMed

Christensen, A J; Moran, P J; Lawton, W J; Stallman, D; Voigts, A L

1997-05-01

Previous research involving individuals facing chronic health problems suggests that an attentional style characterized by pronounced monitoring of threat-relevant information is associated with poorer behavioral and emotional adjustment. This study examined the hypothesis that a pronounced monitoring style would be associated with poorer medical regimen adherence in a sample of 51 chronic hemodialysis patients. Hierarchical regression analyses (controlling for demographic factors and trait anxiety) revealed that "high monitors" exhibited higher interdialysis weight gains and higher serum K values reflecting poorer adherence to fluid-intake and dietary restrictions. However, monitoring was not associated with a measure of medication adherence. Partial support was found for a model suggesting that a lack of perceived control is responsible for the relationship between higher monitoring and poorer adherence.

Interventions to improve adherence to inhaled steroids for asthma.

PubMed

Normansell, Rebecca; Kew, Kayleigh M; Stovold, Elizabeth

2017-04-18

Despite its proven efficacy in improving symptoms and reducing exacerbations, many patients with asthma are not fully adherent to their steroid inhaler. Suboptimal adherence leads to poorer clinical outcomes and increased health service utilisation, and has been identified as a contributing factor to a third of asthma deaths in the UK. Reasons for non-adherence vary, and a variety of interventions have been proposed to help people improve treatment adherence. To assess the efficacy and safety of interventions intended to improve adherence to inhaled corticosteroids among people with asthma. We identified trials from the Cochrane Airways Trials Register, which contains studies identified through multiple electronic searches and handsearches of other sources. We also searched trial registries and reference lists of primary studies. We conducted the most recent searches on 18 November 2016. We included parallel and cluster randomised controlled trials of any duration conducted in any setting. We included studies reported as full-text articles, those published as abstracts only and unpublished data. We included trials of adults and children with asthma and a current prescription for an inhaled corticosteroid (ICS) (as monotherapy or in combination with a long-acting beta 2 -agonist (LABA)). Eligible trials compared an intervention primarily aimed at improving adherence to ICS versus usual care or an alternative intervention. Two review authors screened the searches, extracted study characteristics and outcome data from included studies and assessed risk of bias. Primary outcomes were adherence to ICS, exacerbations requiring at least oral corticosteroids and asthma control. We graded results and presented evidence in 'Summary of findings' tables for each comparison.We analysed dichotomous data as odds ratios, and continuous data as mean differences or standardised mean differences, all using a random-effects model. We described skewed data narratively. We made no a priori assumptions about how trials would be categorised but conducted meta-analyses only if treatments, participants and the underlying clinical question were similar enough for pooling to make sense. We included 39 parallel randomised controlled trials (RCTs) involving adults and children with asthma, 28 of which (n = 16,303) contributed data to at least one meta-analysis. Follow-up ranged from two months to two years (median six months), and trials were conducted mainly in high-income countries. Most studies reported some measure of adherence to ICS and a variety of other outcomes such as quality of life and asthma control. Studies generally were at low or unclear risk of selection bias and at high risk of biases associated with blinding. We considered around half the studies to be at high risk for attrition bias and selective outcome reporting.We classified studies into four comparisons: adherence education versus control (20 studies); electronic trackers or reminders versus control (11 studies); simplified drug regimens versus usual drug regimens (four studies); and school-based directly observed therapy (three studies). Two studies are described separately.All pooled results for adherence education, electronic trackers or reminders and simplified regimens showed better adherence than controls. Analyses limited to studies using objective measures revealed that adherence education showed a benefit of 20 percentage points over control (95% confidence interval (CI) 7.52 to 32.74; five studies; low-quality evidence); electronic trackers or reminders led to better adherence of 19 percentage points (95% CI 14.47 to 25.26; six studies; moderate-quality evidence); and simplified regimens led to better adherence of 4 percentage points (95% CI 1.88 to 6.16; three studies; moderate-quality evidence). Our confidence in the evidence was reduced by risk of bias and inconsistency.Improvements in adherence were not consistently translated into observable benefit for clinical outcomes in our pooled analyses. None of the intervention types showed clear benefit for our primary clinical outcomes - exacerbations requiring an oral corticosteroid (OCS) (evidence of very low to low quality) and asthma control (evidence of low to moderate quality); nor for our secondary outcomes - unscheduled visits (evidence of very low to moderate quality) and quality of life (evidence of low to moderate quality). However, some individual studies reported observed benefits for OCS and use of healthcare services. Most school or work absence data were skewed and were difficult to interpret (evidence of low quality, when graded), and most studies did not specifically measure or report adverse events.Studies investigating the possible benefit of administering ICS at school did not measure adherence, exacerbations requiring OCS, asthma control or adverse events. One study showed fewer unscheduled visits, and another found no differences; data could not be combined. Pooled results suggest that a variety of interventions can improve adherence. The clinical relevance of this improvement, highlighted by uncertain and inconsistent impact on clinical outcomes such as quality of life and asthma control, is less clear. We have low to moderate confidence in these findings owing to concerns about risk of bias and inconsistency. Future studies would benefit from predefining an evidence-based 'cut-off' for acceptable adherence and using objective adherence measures and validated tools and questionnaires. When possible, covert monitoring and some form of blinding or active control may help disentangle effects of the intervention from effects of inclusion in an adherence trial.

Floating cultivation of marine cyanobacteria using coal fly ash.

PubMed

Matsumoto, M; Yoshida, E; Takeyama, H; Matsunaga, T

2000-01-01

The aim of this study was to develop improved methodologies for bulk culturing of biotechnologically useful marine cyanobacteria in the open ocean. We have investigated the viability of using coal fly ash (CFA) blocks as the support medium in a novel floating culture system for marine micro-algae. The marine cyanobacterium Synechococcus sp. NKBG 040607 was found to adhere to floating CFA blocks in liquid culture medium. Maximum density of attached cells of 2.0 x 10(8) cells/cm2 was achieved using seawater. The marine cyanobacterium Synechococcus sp. NKBG 042902 weakly adhered to floating CFA blocks in BG-11 medium. Increasing the concentration of calcium ion in the culture medium enhanced adherence to CFA blocks.

Discordance between surgical care improvement project adherence and postoperative outcomes: implications for new Joint Commission standards.

PubMed

Chang, Victor; Blackwell, Robert H; Markossian, Talar; Yau, Ryan M; Blanco, Barbara A; Zapf, Matthew A C; Abood, Gerard J; Gupta, Gopal N; Kuo, Paul C; Kothari, Anai N

2017-05-15

Infectious (INF) and venous thromboembolism (VTE) complication rates are targeted by surgical care improvement project (SCIP) INF and SCIP VTE measures. We analyzed how adherence to SCIP INF and SCIP VTE affects targeted postoperative outcomes (wound complication [WC], deep vein thrombosis, and pulmonary embolism [PE]) using all-payer data. A retrospective review (2007-2011) was conducted using Healthcare Cost and Utilization Project State Inpatient Database Florida and Medicare's Hospital Compare. The association between SCIP adherence rates and outcomes across 355 included surgical procedures was measured using multilevel mixed-effects linear regression models. One hundred sixty acute care hospitals and 779,922 patients were included. Over 5 y, SCIP INF-1, -2, and -3 adherence improved by 12.5%, 8.0%, and 20.9%, respectively, whereas postoperative WC rate decreased by 14.8%. When controlling for time, SCIP INF-1 adherence was associated with improvement of postoperative WC rates (β = -0.0044, P = 0.005), whereas SCIP INF-2 adherence was associated with increased WCs (β = 0.0031, P = 0.018). SCIP VTE-1, -2 adherence improved by 14.6% and 20.2%, respectively, whereas postoperative deep vein thrombosis rate increased by 7.1% and postoperative PE rate increased by 3.7%. SCIP VTE-1 and -2 adherence were both associated with increased postoperative PE when controlling for time (SCIP VTE-1: β = 0.0019, P < 0.001; SCIP VTE-2: β = 0.0015, P < 0.001). Readmission analysis found SCIP INF-1 adherence to be associated with improved 30-d WC rates when controlling for patient and hospital characteristics (β = -0.0021, P = 0.032), whereas SCIP INF-3 adherence was associated with increased 30-d WC rates when controlling for time (β = 0.0007, P = 0.04). Only SCIP INF-1 adherence was associated with improved outcomes. The Joint Commission has retired SCIP INF-2, -3, and SCIP VTE-2 and made SCIP INF-1 and VTE-1 reporting optional. Our study supports continued reporting of SCIP INF-1. Copyright © 2017 Elsevier Inc. All rights reserved.