33 results on '"Vamos, S."'
Search Results
2. Acceptability and use of sexual barrier products and lubricants among HIV-seropositive Zambian men
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Jones, D.L., Weiss, S.M., Chitalu, N., Mumbi, M., Shine, A., Vamos, S., and Villar, O.
- Subjects
BioFilm Inc. ,Lubrication and lubricants -- Usage ,HIV patients ,Health - Abstract
This study assessed the acceptability and preference for sexual barrier and lubricant products among men in Zambia following trial and long-term use. It also examined the role of men's preferences as facilitators or impediments to product use for HIV transmission reduction within the Zambian context. HIV-seropositive and- serodiscordant couples were recruited from HIV voluntary counseling and testing centers in Lusaka between 2003 and 2006; 66% of those approached agreed to participate. HIV seropositive male participants participated in a product exposure group intervention (n = 155). Participants were provided with male and female condoms and vaginal lubricants (Astroglide[R] [BioFilm, Inc., Vista, CA] & KY[R] gels [Johnson & Johnson, Langhorne, PA], Lubrin[R] suppositories [Kendwood Therapuetics, Fairfield, NJ]) over three sessions; assessments were conducted at baseline, monthly over 6 months and at 12 months. At baseline, the majority of men reported no previous exposure to lubricant products or female condoms and high (79%) levels of consistent male condom use in the last 7 days. Female condom use increased during the intervention, and male condom use increased at 6 months and was maintained over 12 months. The basis for decisions regarding lubricant use following product exposure was most influenced by a preference for communicating with partners; participant preference for lubricant products was distributed between all three products. Results illustrate the importance of development of a variety of products for prevention of HIV transmission and of inclusion of male partners in interventions to increase sexual barrier product use to facilitate barrier acceptability and use in Zambia.
- Published
- 2008
3. Fluorescent analysis in polarized MDCK cell monolayers: intracellular pH and calcium interactions after apical and basolateral stimulation with arginine vasopressin
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Welling Lw, Thomas B. Wiegmann, and Vamos S
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Vasopressin ,Arginine ,Physiology ,Chemistry ,Intracellular pH ,Sodium ,chemistry.chemical_element ,Cell Biology ,Hydrogen-Ion Concentration ,Calcium ,Calcium in biology ,Arginine Vasopressin ,Microscopy, Fluorescence ,Biochemistry ,Extracellular ,Biophysics ,Animals ,Molecular Biology ,Cells, Cultured ,Calcium signaling - Abstract
Intracellular calcium ([Ca2+]i) and hydrogen ion concentrations (pHi) are important regulators of cell function. Those ions also may interact and it is important, therefore, to measure their concentrations simultaneously. In the present studies we used a system developed for that purpose, a fluorescent emission ratio technique for simultaneous analysis of calcium (Indo-1) and pH (SNARF-1) in single cells at video rates, and determined if arginine vasopressin (AVP, 12.5 mumol/l) evoked [Ca2+]i and pHi signals interact in MDCK cells. We also employed a simple system for analysing the side specific (basolateral or apical) application of agonist to polarized cell layers on permeable membranes. AVP is found to evoke simultaneous changes in both pHi and [Ca2+]i. Basolateral application induced transient acidification, followed by partial recovery, and a [Ca2+]i transient with kinetic pattern similar to that of the pHi. Apical application also caused a mirror image pHi and [Ca2+]i pattern but of smaller magnitude (no peak). Selective removal of extracellular calcium ([Ca2+]e) or sodium ([Na+]e) dissociated the pHi and [Ca2+]i responses in both cases. Na+e removal abolished the pHi changes, but not the [Ca2+]i transients. [Ca2+]e removal abolished the [Ca2+]i changes and reduced, but did not abolish, the pHi responses. Thus, AVP induces pHi changes which are modified by calcium while calcium signalling is not modified by changes in pHi.
- Published
- 1996
4. Iron uptake promotes hyperoxic injury to alveolar macrophages
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Wade L. Williams, Kirstin Bailey, Thomas B. Wiegmann, Vamos S, Lewis Wesselius, and Amy O'Brien-Ladner
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Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Iron ,chemistry.chemical_element ,Saccharomyces cerevisiae ,Calcium ,Hyperoxia ,Critical Care and Intensive Care Medicine ,medicine.disease_cause ,chemistry.chemical_compound ,Phagocytosis ,Lactate dehydrogenase ,Internal medicine ,Macrophages, Alveolar ,medicine ,Humans ,Calcium metabolism ,biology ,L-Lactate Dehydrogenase ,Osmolar Concentration ,Transferrin ,Metabolism ,Intracellular Membranes ,Ferritin ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Biochemistry ,Ferritins ,biology.protein ,medicine.symptom ,Pulmonary alveolus ,Bronchoalveolar Lavage Fluid ,Oxidative stress - Abstract
Iron uptake by cells may increase the intracellular pool of prooxidant iron prior to storage of iron within ferritin. Because hyperoxia is toxic to alveolar macrophages (AM) via mechanisms involving oxidant stress, we hypothesized that iron uptake by AM might promote hyperoxia-induced injury. To assess this hypothesis, we cultured AM recovered from healthy volunteers under conditions of normoxia or hyperoxia (60% or 95% oxygen) in media of varying iron content, including control media (3 microM iron) and media supplemented with iron (FeCl3; total iron 10, 20, or 40 microM). AM injury was assessed by measuring release of lactate dehydrogenase (LDH), phagocytic activity for yeast, and cytosolic concentrations of calcium ([Ca2+]i) as determined by ratio image analysis of AM loaded with the fluorescent calcium probe indo-1. There was dose-dependent accumulation of iron and ferritin synthesis in AM exposed to iron-supplemented media. Exposure of AM to hyperoxia (60% and 95% oxygen, 18 h) in control media increased LDH release and impaired phagocytic activity for yeast; however, similar hyperoxic exposures in iron-supplemented media significantly increased the cells' LDH release and decreased phagocytosis. Exposure to 95% oxygen increased the [Ca2+]i of AM over 18 h, but similar exposure in iron-supplemented media induced greater increases in [Ca2+]i. As compared with exposure to normoxia, exposure to hyperoxia (60% and 95% oxygen) also decreased iron uptake and, to a greater extent, ferritin synthesis by AM in iron-supplemented media. These data suggest that: (1) iron uptake promotes hyperoxic injury to AM; and (2) hyperoxia impairs the capacity of AM to sequester iron in ferritin.
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- 1999
5. Reducing the risk of HIV infection during pregnancy among South African women: A randomized controlled trial
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Jones, D. L., primary, Peltzer, K., additional, Villar-Loubet, O., additional, Shikwane, E., additional, Cook, R., additional, Vamos, S., additional, and Weiss, S. M., additional
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- 2013
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6. Simultaneous imaging of intracellular [Ca2+] and pH in single MDCK and glomerular epithelial cells
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Welling Lw, S. J. Morris, D. E. Howard, D. M. Beatty, Vamos S, and Thomas B. Wiegmann
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Indoles ,Physiology ,Intracellular pH ,Kidney Glomerulus ,chemistry.chemical_element ,Calcium ,Indo-1 ,Kidney ,Calcium in biology ,Ammonium Chloride ,Epithelium ,Cell Line ,chemistry.chemical_compound ,Extracellular ,medicine ,Animals ,Fluorescent Dyes ,Chemistry ,Osmolar Concentration ,Epithelial Cells ,Cell Biology ,Intracellular Membranes ,Hydrogen-Ion Concentration ,Fluorescence ,medicine.anatomical_structure ,Biochemistry ,Biophysics ,Intracellular - Abstract
The interrelationships between changes in intracellular calcium concentration ([Ca2+]i) and intracellular pH in Madin-Darby canine kidney cells and kidney glomerular epithelial cells exposed to various stimuli were analyzed simultaneously using a new design of a fluorescence video microscope. Cells were double labeled with indo 1 and SNARF 1 dyes and were excited simultaneously at 350 and 540 nm. Images at four emission wavelengths were captured simultaneously at 405, 475, 575, and 640 nm at 30 frames/s for the two ratio dyes. SNARF sensitivity to pH between 6.5 and 8.0 was unchanged by [Ca2+]i. The SNARF ratio maps were used to correct the pH-dependent changes in the calculation of local cell calcium. NH4Cl loading produced the expected alkalinization and a concurrent rise in [Ca2+]i. When the NH4Cl was removed and the cells became acidic, a second rise in [Ca2+]i was recorded. Both changes in [Ca2+]i were from intracellular stores since they persisted in the absence of extracellular calcium. The findings demonstrate the need for pH correction of indo 1 recordings.
- Published
- 1993
7. Community-Based Risk Reduction in Zambia
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Jones, D. L., primary, Weiss, S. M., additional, Waldrop-Valverde, D., additional, Chitalu, N., additional, Mumbi, M., additional, and Vamos, S., additional
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- 2008
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8. Calcitonin stimulates growth of human prostate cancer cells through receptor-mediated increase in cyclic adenosine 3',5'-monophosphates and cytoplasmic Ca2+ transients.
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Shah, G V, primary, Rayford, W, additional, Noble, M J, additional, Austenfeld, M, additional, Weigel, J, additional, Vamos, S, additional, and Mebust, W K, additional
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- 1994
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9. Simultaneous imaging of intracellular [Ca2+] and pH in single MDCK and glomerular epithelial cells
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Wiegmann, T. B., primary, Welling, L. W., additional, Beatty, D. M., additional, Howard, D. E., additional, Vamos, S., additional, and Morris, S. J., additional
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- 1993
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10. Strategies for living with the challenges of HIV and antiretroviral use in Zambia.
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Jones D, Zulu I, Mumbi M, Chitalu N, Vamos S, Gomez J, and Weiss SM
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This study sought to identify strategies for living with the challenges of HIV and antiretroviral (ARV) use among new medication users in urban Zambia. Participants (n = 160) were recruited from urban Lusaka, Zambia. Qualitative Data was drawn from monthly ARV treatment education intervention groups addressing HIV and antiretroviral use. Themes included community stigma, nutrition, social support and HIV/ARV knowledge, concerns and beliefs. Strategies for adherence included family, friends, and community organizations that provided emotional and financial support regarding medication, feelings of depression, help with household duties, transportation and companionship at clinic visits and assistance during illness. Social support was the most frequent strategy in coping with ARV use. Challenges included learning to take medications regularly (51%), remembering information about medication (29%), clinic wait times (24%), timing of doses (28%), transportation (23%), food (23%) and lack of social support (23%). Results highlight needed programs to support nutritional supplementation and reduce stigma and the utility of support groups targeting new ARV users to enhance health and encourage sharing of challenges and solutions for consistent ARV use. Strategies for the establishment of health behaviors supporting medication use early in ARV prescription are presented as an important element in long term adherence. [ABSTRACT FROM AUTHOR]
- Published
- 2009
11. Nature's pharmacy: do you have a green tongue?
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Vamos S
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- 2005
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12. Book Review
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S. J. Morris, Welling Lw, Vamos S, Thomas B. Wiegmann, and D. M. Beatty
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Pituitary gland ,medicine.medical_specialty ,Kidney ,Chemistry ,business.industry ,chemistry.chemical_element ,Bradykinin ,Calcium ,Epithelium ,Pathology and Forensic Medicine ,chemistry.chemical_compound ,medicine.anatomical_structure ,Text mining ,Endocrinology ,Internal medicine ,medicine ,Vasoconstrictor Agents ,business ,Intracellular - Published
- 1989
13. COVID-19 and college students: health literacy experiences and training needs.
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Vamos S, Lee T, Kang HB, and Vamos CA
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- Humans, Students psychology, Pandemics, Universities, COVID-19 epidemiology, Health Literacy
- Abstract
Objective: To explore health literacy (HL) experiences, needs, and future training directions among college students enrolled in health-related degree programs during the COVID-19 pandemic., Participants: Students ( n = 169) enrolled in a health-related degree program at a state university in the mid-western U.S. completed an online survey., Methods: Forty-five questions were developed assessing: (1) demographics; (2) HL; (3) health behaviors; (4) health/well-being; and (5) academic/financial impacts. A HL score across four domains (access, understand, appraise, apply) was calculated. Participants were categorized as having sufficient or insufficient HL. Associations between HL and categorical variables were tested (Chi-square/Fisher's exact tests). Comparisons between sufficient and insufficient HL were performed (Wilcoxon rank-sum tests)., Results: Participants had sufficient (55.6%) and insufficient (44.4%) HL. Age was statistically significant with HL ( p < 0.5). The top three future training needs were identified (psychological impact, diagnostic/prevention/treatment, racial/ethnic disparities)., Conclusions: Emerging health professionals reported sufficient HL, yet information gaps and training needs remain.
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- 2023
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14. A Conceptual Model Map on Health and Nutrition Behavior (CMM HB/NB ).
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Schlüter K, Vamos S, Wacker C, and Welter VDE
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- Health Literacy, Humans, Models, Theoretical, Nutrition Policy, Surveys and Questionnaires, Health Behavior, Health Knowledge, Attitudes, Practice, Intention
- Abstract
The Conceptual Model Map (CMM) presented here is intended to show the connections between different theories and constructs in the field of health and nutrition behavior (including literacy models, the knowledge-attitude(s)-practice(s) survey structure (KAP), behavior change theories, and Maslow's pyramid of needs). The CMM can be used as a map to locate existing and future studies, to show their range of effect as well as their limitations. In this context, the CMM also reveals reasons for the attitude/intention-behavior gap.
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- 2020
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15. Interdisciplinary Perspectives on Health Literacy Research Around the World: More Important Than Ever in a Time of COVID-19.
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Sentell T, Vamos S, and Okan O
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- Betacoronavirus, COVID-19, Health Equity, Humans, Policy Making, Public Health, SARS-CoV-2, Coronavirus Infections, Health Knowledge, Attitudes, Practice, Health Literacy, Health Promotion, Pandemics, Pneumonia, Viral
- Abstract
As we write our editorial for a health literacy special issue in the midst of the international COVID-19 crisis, we take this opportunity to highlight the importance of individual, community, and population health literacy. We are not only in a "pandemic" but also an "infodemic". Health literacy is more important than ever in the face of these global health threats, which have impacted outcomes across the levels of the socio-ecological model (SEM), including individual health behaviors, family relationships, organizational behavior, state policy-making, national mortality statistics, and the international economy in the span of weeks. Our special issue sought to pull together interdisciplinary threads guided by two principles. The first was defining health literacy as essential skills and situational resources needed for people to find, understand, evaluate, communicate, and use information and services in a variety of forms across various settings throughout their life course to promote health and wellbeing. The second was the idea that enhancing health literacy in populations and systems is critical to achieving health equity. In this time of public health need across traditional borders, the inter-sectoral and international perspectives of special issue articles are more urgent than ever. A greater understanding, appreciation, and application of health literacy can support policy action on multiple levels to address major public health challenges. Health literacy should be built deliberately as a population-level resource and community asset. We have summarized the set of articles in this special issue across the levels of the SEM, hoping their thoughtful considerations and interesting findings will help to support global health and wellness and inspire future research, policy, and practice in this global public health emergency and beyond.
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- 2020
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16. Making a Case for "Education for Health Literacy": An International Perspective.
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Vamos S, Okan O, Sentell T, and Rootman I
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- Canada, Education, Germany, Humans, Health Literacy, Health Promotion, Internationality
- Abstract
In many countries, health literacy research, practice, and policy have been moving away from a focus only on medical care and health-care settings to a much broader conceptualization. In this broader perspective, health literacy can be obtained and used across many other settings (e.g., school, home, workplaces, government) towards achieving health and wellness goals across the life-course for individuals, families, and communities. The education sector is a critical domain towards these achievements and education for health literacy is a fundamental process and outcome. This can help towards important public health goals, including critical health literacy, as oriented not only towards individual actions, but also towards supporting effective social and political action. This Perspective Article describes the importance and utility of the education for health literacy perspective, which, follows a view that health literacy is a key outcome of health education from which improved population health, health promotion and disease prevention could be achieved across diverse contexts. We first describe different educational paradigms to address health literacy and clarify the education for health literacy perspective as a supportive, instructional and capacity-building global resource across the life-course. Then, using specific examples from Canada, America, and Germany, we provide a snapshot of the diverse ways in which the education for health literacy perspective can be found in national policies. These include broad national goals and standards (Germany and Canada) and major health care reform (America). We next consider the tensions and gaps that can arise in the translation and implementation of these policies relative to the ideal education for health literacy perspective, especially related to equity. These include the need for funding, goals of the educational system, and limited evaluation of policy in practice. Finally, we highlight strategic opportunities to achieve education for health literacy and equity especially offering examples from innovative practice in Canada across the lifespan.
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- 2020
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17. Applying a health literacy lens to youth sport: a focus on doping prevention in Germany.
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Vamos S and Steinmann A
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- Adolescent, Child, Doping in Sports psychology, Germany epidemiology, Humans, Young Adult, Youth Sports psychology, Doping in Sports prevention & control, Health Literacy methods
- Abstract
There are two camps when it comes to youth in high-performance sports and whether competition is good or destructive. Despite opportunities for positive development, the demands of increasing competitive levels and related situational stressors among young athletes can be a double-edged sword. Doping is becoming increasingly popular and more readily available to the youth sports population. Improving the health of youth in competitive sport requires us to think about health and its determinants in a more sophisticated manner. We share a current initiative in Germany that reflects this broader thinking by integrating 'education for health literacy' as one strategy in youth sport settings with regard to doping prevention. Implications and emerging opportunities to take further action for doping prevention and health improvement applicable for German and global contexts are offered.
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- 2019
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18. Developing an online health literacy curriculum for two German universities: a key stakeholder approach.
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Vamos S, Yeung P, Schaal S, and Schlüter K
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- Adult, Canada, Female, Germany, Humans, Male, Students, Universities, Young Adult, Education, Distance methods, Focus Groups methods, Health Literacy methods
- Abstract
Health literacy is a significant resource for daily life in society. Global evidence reveals that there are less than ideal levels of health literacy in populations. One potential straproviding them with the skills and tools that will improve their knowledge and practice as our future workforce. The purpose of this study was to articulate the need to develop an online health literacy introductory course for university students in Germany. A total of 16 students from two German universities participated in focus group interviews to collect data on the extent of student health literacy awareness and related health and education needs. Nine international stakeholders participated in an online self-guided review of a comprehensive draft course to obtain detailed feedback from experts in the education and health literacy fields. Results revealed that both focus group and international stakeholders are in support of developing an online health literacy curriculum. To build the draft curriculum, an existing Canadian health literacy online course was adapted as a blueprint for the German context. The proposed course was customized based on the findings from the focus groups and international stakeholder feedback, which is intended to help inform and determine contents, design, and delivery of such a course applicable for universities in Germany and beyond.
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- 2018
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19. Our self-tracking movement and health literacy: are we really making every moment count?
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Vamos S and Klein K
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- Humans, Mobile Applications, Health Literacy methods, Medical Informatics instrumentation
- Abstract
There is a growing movement related to self-tracking in the quest for better health. Why do so many people like to use 'intelligent tools' like shiny sensors or mobile apps to keep an eye on every move? Do they really help us drive sustained healthy behavioral changes? Despite technological advances and product promises, we must remember that technology alone does not facilitate change to optimize health benefits. The purpose of the commentary is to pose the question: How 'health literate' do we have to be to reap the actionable health benefits of self-tracking? Research has revealed the prevalence of limited health literacy across the globe. Health literacy involves a complex set of inter-connected skills, including acting upon health information. This commentary puts attention on health literacy as an essential human tool to better equip people to overcome barriers and use devices to leverage their full potential.
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- 2018
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20. Translation and sustainability of an HIV prevention intervention in Lusaka, Zambia.
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Vamos S, Mumbi M, Cook R, Chitalu N, Weiss SM, and Jones DL
- Abstract
The scale-up of HIV treatment programs in sub-Saharan Africa necessitates creative solutions that do not further burden the health system to meet global initiatives in prevention and care. This study assessed the work environment and impact of providing a behavioral risk reduction intervention in six community health centers (CHCs) in Lusaka, Zambia; opportunities and challenges to long-term program sustainability were identified. CHC staff participants (n = 82) were assessed on perceived clinic burden, job satisfaction, and burnout before and after implementation of the intervention. High levels of clinic burden were identified; however, no increase in perceived clinic burden or staff burnout was associated with providing the intervention. The intervention was sustained at the majority of CHCs and also adopted at additional clinics. Behavioral interventions can be successfully implemented and maintained in resource-poor settings. Creative strategies to overcome structural and economic challenges should be applied to enhance translation research.
- Published
- 2014
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21. Cognitive functioning, depression, and HIV medication adherence in India: a randomized pilot trial.
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Cook R, Waldrop-Valverde D, Sharma A, Vamos S, Mahajan B, Weiss SM, Kumar M, Nehra R, and Jones DL
- Abstract
Objective : India is home to the third-largest number of people living with HIV in the world, and no-cost antiretroviral therapy (ART) has been available across the country since 2004. However, rates of adherence to ART are often subpar in India, and interventions to increase adherence are warranted. Cognitive impairment and depression have been associated with ART non-adherence, and may also limit the impact of behavioral interventions designed to improve adherence. Studies have not evaluated the impact of cognitive impairment and depression on response to adherence interventions in India. Methods : Individuals new to ART (≤12 months prescribed) were recruited from a public hospital in Chandigarh, India. Participants ( N = 80) were randomized to either a group medication adherence intervention (MAI) or an enhanced standard of care (ESOC) condition. The MAI consisted of three monthly gender-concordant group cognitive-behavioral sessions addressing HIV and ART, adherence, and HIV-related coping and social support. Participants were assessed at baseline for depression and cognitive functioning, and assessed monthly for adherence by pill count. Results : Adherence among participants receiving the MAI improved by about one day's dose over the course of the study, and no improvement was noted among those in the ESOC. Additionally, high rates of cognitive impairment (57%) and depression (25%) were identified among participants. There was no evidence that cognitive impairment moderated response to the intervention. However, while non-depressed participants benefitted from the intervention, depressed participants failed to show the same improvement. Conclusions : Results of this pilot study suggest that group behavioral interventions can be an effective strategy to promote ART adherence in this population, even among those demonstrating cognitive impairment. However, because of the negative impact of depression on adherence, future studies should continue to develop strategies to identify and treat it among people living with HIV in India.
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- 2014
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22. Enhancing HIV medication adherence in India.
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Jones D, Sharma A, Kumar M, Waldrop-Valverde D, Nehra R, Vamos S, Cook R, and Weiss SM
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- Adolescent, Adult, Cross-Over Studies, HIV Infections psychology, Humans, India, Male, Middle Aged, Pilot Projects, Viral Load, Young Adult, Anti-Retroviral Agents therapeutic use, HIV Infections drug therapy, Medication Adherence
- Abstract
Background: This pilot study evaluated an intervention designed to enhance adherence among those new to antiretroviral therapy., Methods: Participants (n = 80) were recruited from a hospital clinic in Chandigarh, India, and randomized to a 3-month group intervention or individual enhanced standard of care followed by crossover of condition and assessed over 6 months. Adherence was measured by prescription refill, pill count, and self-report., Results: At baseline, 56% of group condition (immediate intervention) and 54% of individual condition (delayed intervention) participants were nonadherent by pill count and 23% of group and 26% of individual condition participants self-reported skipping medication at least once over the last 3 months. From the postintervention to long-term follow-up, adherence in the group condition (immediate intervention) improved in comparison with adherence in the individual condition (delayed intervention; χ(2) = 5.67, P = .02)., Conclusions: Results support the use of interventions early in treatment to provide information and social support to establish long-term healthy adherence behaviors.
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- 2013
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23. Determinants of engagement in HIV treatment and care among Zambians new to antiretroviral therapy.
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Jones DL, Zulu I, Vamos S, Cook R, Chitalu N, and Weiss SM
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- Adolescent, Adult, Ambulatory Care, Anti-HIV Agents administration & dosage, Antiretroviral Therapy, Highly Active methods, CD4 Lymphocyte Count, Cross-Over Studies, Female, HIV Infections psychology, Health Services Accessibility, Humans, Male, Middle Aged, Office Visits, Physician-Patient Relations, Pilot Projects, Psychiatric Status Rating Scales, Social Stigma, Social Support, Socioeconomic Factors, Surveys and Questionnaires, Treatment Outcome, Viral Load, Young Adult, Zambia, Anti-HIV Agents therapeutic use, HIV Infections drug therapy, Patient Compliance
- Abstract
This pilot study assessed the determinants of engagement in HIV care among Zambian patients new to antiretroviral (ARV) therapy, and the effect of an intervention to increase medication adherence. Participants (n = 160) were randomized to a 3-month group or individual intervention utilizing a crossover design. Psychophysiological (depression, cognitive functioning, health status), social (social support, disclosure, stigma), structural factors (health care access, patient-provider communication), and treatment engagement (adherence to clinic visits and medication) were assessed. Participants initially receiving the group intervention improved their adherence, but gains were not maintained following crossover to the individual intervention. Increased social support and patient-provider communication and decreased concern about HIV medications predicted increased clinic attendance across both arms. Results suggest that early participation in a group intervention may promote increased adherence among patients new to ARV therapy, but long-term engagement in care may be sustained by both one-on-one and group interventions by health care staff., (Copyright © 2013 Association of Nurses in AIDS Care. Published by Elsevier Inc. All rights reserved.)
- Published
- 2013
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24. Quality of relationship and sexual risk behaviors among HIV couples in Lusaka, Zambia.
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Vamos S, Cook R, Chitalu N, Mumbi M, Weiss SM, and Jones D
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- Adult, Condoms, Female, Humans, Male, Object Attachment, Risk Factors, Risk-Taking, Safe Sex, Zambia, Family Characteristics, HIV Infections prevention & control, HIV Infections psychology, Sexual Behavior psychology, Sexual Partners psychology
- Abstract
Relationship quality and partner dynamics provide important insights into understanding sexual behavior within HIV sero-positive and sero-discordant couples. Individuals in long-term partnerships may be vulnerable to HIV/sexually transmitted infections (STI) within their relationships due to misperceptions of their partners risk behaviors and potential concurrent (e.g., extramarital, nonprimary) sexual partnerships. This study sought to examine relationship quality among HIV sero-positive and sero-discordant couples in Zambia, and its association with safer sex behavior. This study utilized data drawn from an ongoing translational study, The Partnership II Project - a couples-based sexual risk reduction intervention in Lusaka, Zambia. Couples (n=240) were assessed on demographics, relationship quality, and sexual risk behavior. Overall, couples perceiving their relationships more positively engaged in less risky sexual behavior (i.e., more condom use (b=0.011, t=3.14, p=0.002) and fewer partners (χ(2)=11.4, p=0.003). Within the dyad, condom use was "actor driven," indicating that the association between relationship quality and condom use did not depend on the partner's evaluation of the relationship. Safer sex behavior was positively influenced by communication about condoms. Results support the paradigm shift from prevention strategies with HIV-positive and at-risk individuals to concentrated efforts addressing male-female dyads, and suggest that interventions to address the role of couples' relationship quality, a modifiable target for decreasing sexual risk behavior, are needed.
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- 2013
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25. A Cultural Perspective on Sexual Health: HIV Positive and Negative Monolingual Hispanic Women in South Florida.
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Villar-Loubet OM, Vamos S, Jones DL, Lopez E, and Weiss SM
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This study explored feelings and attitudes with regard to HIV and sexual health among 82 monolingual Spanish-speaking, HIV-positive ( n = 30) and at-risk women ( n = 52), participating in the NOW en Español Project-a cognitive behavioral sexual risk-reduction intervention in Miami, Florida. Hispanic cultural values and beliefs, such as machismo, marianismo, and sexual silence, emerged throughout the intervention as important determinants of sexual behavior. Recommendations for integrating these culture-specific issues in sexual health interventions for Hispanic women are provided.
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- 2011
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26. Sexual risk reduction among Zambian couples.
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Jones DJ, Chitalu N, Ndubani P, Mumbi M, Weiss SM, Villar-Loubet O, Vamos S, and Waldrop-Valverde D
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- Counseling, Female, HIV Infections epidemiology, HIV Infections psychology, HIV Seroprevalence, Humans, Lubricants, Male, Patient Acceptance of Health Care, Patient Compliance, Patient Education as Topic, Spouses statistics & numerical data, Urban Population statistics & numerical data, Zambia epidemiology, Condoms statistics & numerical data, HIV Infections prevention & control, HIV Seronegativity, HIV Seropositivity psychology, Health Promotion, Risk Reduction Behavior, Safe Sex, Spouses psychology
- Abstract
Zambia has over 1 million HIV infections nationwide and an urban prevalence rate of 23%. This study compared the impact of male involvement in multiple and single session risk reduction interventions among inconsistent condom users in Zambia and the role of serostatus among HIV-seropositive and serodiscordant couples. Couples (N=392) were randomised into intervention arms. Among inconsistent condom users at baseline (N=83), condom use increased in both conditions and this increase was maintained over a 12- month period. At 12 months, seronegative men in the multiple session condition increased sexual barrier (male and female condoms) use in comparison with those in the single session condition (F=16.13, =0.001) while seropositive individuals increased sexual barrier use regardless of condition. Results illustrate the importance of both single and multiple session risk reduction counseling among seronegative men in serodiscordant couples in Zambia, and highlight the differing perception of risk between seropositive and serodiscordant persons.
- Published
- 2009
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27. Experiences of beginning health educators and changes in their high school students' health behaviors and attitudes.
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Vamos S
- Subjects
- Adolescent, Data Collection, Faculty, Humans, Interviews as Topic, New England, Attitude to Health, Health Behavior, Health Education
- Abstract
This study explored the instructional experiences of beginning health educators and changes in their high school students' health-related behaviors and attitudes. Qualitative data were collected through observations and personal interviews from five novice health teachers two times per week over an 8-week period. Quantitative data were collected from 92 high school student participants using a 60-item survey with a pretest/posttest administration. Dependent t tests were calculated to detect mean differences between total sample pretest and posttest scores with a significance level, where p < .05. Mean raw scores were calculated in 12 health categories to detect differences between pretest and posttest scores for each of the five individual health classes. A deeper understanding of beginning health teachers' practices, thoughts, and potential effectiveness offered insight into the interplay between teaching, learning, and health. The contribution to the enhancement of professional teacher preparation programs is provided.
- Published
- 2007
- Full Text
- View/download PDF
28. Both subtype 1 and 2 receptors of angiotensin II participate in regulation of intracellular calcium in glomerular epithelial cells.
- Author
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Sharma R, Sharma M, Vamos S, Savin VJ, and Wiegmann TB
- Subjects
- Angiotensin II pharmacology, Animals, Bradykinin pharmacology, Calcium Signaling drug effects, Cells, Cultured, Endoplasmic Reticulum metabolism, Enzyme Inhibitors pharmacology, Epithelial Cells cytology, Epithelial Cells drug effects, Hydrogen-Ion Concentration drug effects, In Vitro Techniques, Inositol 1,4,5-Trisphosphate metabolism, Rats, Receptor, Angiotensin, Type 1, Receptor, Angiotensin, Type 2, Thapsigargin pharmacology, Vasoconstrictor Agents pharmacology, Calcium metabolism, Epithelial Cells metabolism, Kidney Glomerulus cytology, Receptors, Angiotensin metabolism
- Abstract
We have documented that both receptors of angiotensin II (ANG II) (AT1 and AT2) are involved in regulation of intracellular signals in glomerular epithelial cells (GECs). We studied the role of these receptors in regulation of intracellular ionized calcium [Ca2(+)]i in GECs. Cells were loaded with Indo-1 (Ca2(+)) and SNARF-1 (pH) fluorescent dyes and then incubated with or without ANG II for 1 hour at 37 degrees C. In some experiments AT(1) and AT(2) receptor blockers (Losartan and PD 12339, respectively) were added. In additional experiments cells were incubated with thapsigargin (Tg) and bradykinin (BK) as well as ANG II. A four-channel fluorescence videomicroscope system was used to measure real-time [Ca2(+) ]i in individual cells. Levels of inositol triphosphate (IP(3)) were measured with radioimmunoassay. An amount of 100 nmol/L of ANG II caused a maximal increase in [Ca2(+)]i in calcium-containing buffer. ANG II had no effect on intracellular pH of GECs. Increase in [Ca2(+)]i by ANG II was prevented by the concurrent use of Losartan and PD 123319. BK caused a transient increase in [Ca2(+)]i, which was significantly decreased by ANG II; concurrent addition of Losartan and PD 123319 prevented ANG II effect. ANG II prevented the accumulation of Ca2(+) in intracellular stores. ANG II caused a significant but transient increase in levels of IP(3). In summary, ANG II increases extracellular/intracellular calcium dependent bidirectional Ca2(+) transport in GECs, inhibits BK induced release of Ca2(+) from IP(3) sensitive stores, and, in addition, reduces refilling of endoplasmic reticulum [Ca2(+)] depleted by repeated BK stimulation. Both receptor subtypes appear to be important in ANG II mediated physiologic responses of GECs and may participate in modulation of glomerular function in vivo.
- Published
- 2001
- Full Text
- View/download PDF
29. Iron uptake promotes hyperoxic injury to alveolar macrophages.
- Author
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Wesselius LJ, Williams WL, Bailey K, Vamos S, O'Brien-Ladner AR, and Wiegmann T
- Subjects
- Bronchoalveolar Lavage Fluid cytology, Calcium metabolism, Ferritins biosynthesis, Humans, Intracellular Membranes metabolism, Iron metabolism, L-Lactate Dehydrogenase metabolism, Osmolar Concentration, Phagocytosis physiology, Saccharomyces cerevisiae physiology, Transferrin pharmacology, Hyperoxia metabolism, Hyperoxia pathology, Iron pharmacokinetics, Macrophages, Alveolar metabolism, Macrophages, Alveolar pathology
- Abstract
Iron uptake by cells may increase the intracellular pool of prooxidant iron prior to storage of iron within ferritin. Because hyperoxia is toxic to alveolar macrophages (AM) via mechanisms involving oxidant stress, we hypothesized that iron uptake by AM might promote hyperoxia-induced injury. To assess this hypothesis, we cultured AM recovered from healthy volunteers under conditions of normoxia or hyperoxia (60% or 95% oxygen) in media of varying iron content, including control media (3 microM iron) and media supplemented with iron (FeCl3; total iron 10, 20, or 40 microM). AM injury was assessed by measuring release of lactate dehydrogenase (LDH), phagocytic activity for yeast, and cytosolic concentrations of calcium ([Ca2+]i) as determined by ratio image analysis of AM loaded with the fluorescent calcium probe indo-1. There was dose-dependent accumulation of iron and ferritin synthesis in AM exposed to iron-supplemented media. Exposure of AM to hyperoxia (60% and 95% oxygen, 18 h) in control media increased LDH release and impaired phagocytic activity for yeast; however, similar hyperoxic exposures in iron-supplemented media significantly increased the cells' LDH release and decreased phagocytosis. Exposure to 95% oxygen increased the [Ca2+]i of AM over 18 h, but similar exposure in iron-supplemented media induced greater increases in [Ca2+]i. As compared with exposure to normoxia, exposure to hyperoxia (60% and 95% oxygen) also decreased iron uptake and, to a greater extent, ferritin synthesis by AM in iron-supplemented media. These data suggest that: (1) iron uptake promotes hyperoxic injury to AM; and (2) hyperoxia impairs the capacity of AM to sequester iron in ferritin.
- Published
- 1999
- Full Text
- View/download PDF
30. Calcium mobilization and protease-activated receptor cleavage after thrombin stimulation in motor neurons.
- Author
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Smirnova IV, Vamos S, Wiegmann T, Citron BA, Arnold PM, and Festoff BW
- Subjects
- Animals, Cell Line, Cholera Toxin pharmacology, GTP-Binding Proteins metabolism, Gene Expression Regulation drug effects, Hybrid Cells, Interphase drug effects, Intracellular Fluid drug effects, Intracellular Fluid metabolism, Lovastatin pharmacology, Mice, Pertussis Toxin, Receptor, PAR-1, Receptors, Thrombin drug effects, Thrombin antagonists & inhibitors, Thrombin drug effects, Virulence Factors, Bordetella pharmacology, Calcium metabolism, Motor Neurons drug effects, Motor Neurons metabolism, Receptors, Thrombin metabolism, Thrombin pharmacology
- Abstract
Thrombin, the ultimate enzyme in the blood coagulation cascade, has prominent actions on various cells, including neurons. As in platelets, thrombin increases [Ca2+]i mobilization in neurons, and also retracts neurites. Both these effects are mediated through a G protein-coupled, proteolytically activated receptor for thrombin (PAR-1). Prolonged exposure to thrombin kills neurons via apoptosis, that may also involve PAR-1 activation. Increased [Ca2+]i has been a unifying mechanism proposed for cell death in several neurodegenerative diseases. Thrombin-elevated calcium levels may activate intracellular cascades in neurons leading to cell death. Since thrombin mediates its diverse effects on cells through both heterotrimeric and monomeric G proteins, we also explored what effect altering differential G protein coupling would have on the neuronal response to thrombin. We studied calcium mobilization by thrombin in a model motor neuronal cell line, NSC19, using fluorescence image analysis. Confirming effects in other neuronal types, thrombin caused dramatic increases in [Ca2+]i levels, both transiently and after prolonged exposure, which involved activation and cleavage of the PAR-1 receptor. Using enzyme linked immunosorbent assay (ELISA) and dot-blot analysis, we found that the N-terminal fragment of PAR-1 was released into the medium after exposure to thrombin. We confirmed that PAR-1 protein and mRNA expression occurred in motor neurons. We found that cholera toxin inhibited thrombin-mediated Ca2+ influx, pertussis toxin did not significantly alter thrombin action, and lovastatin, a small 21-kDa Ras GTPase (Rho) modulator, showed a tendency to reduce the thrombin effect. These data indicate that thrombin-increased [Ca2+]i, sufficient to trigger cell death in motor neurons, might be approached in vivo by modulating thrombin signaling through PAR-1.
- Published
- 1998
- Full Text
- View/download PDF
31. Fluorescent analysis in polarized MDCK cell monolayers: intracellular pH and calcium interactions after apical and basolateral stimulation with arginine vasopressin.
- Author
-
Vamos S, Welling LW, and Wiegmann TB
- Subjects
- Animals, Cells, Cultured, Hydrogen-Ion Concentration, Microscopy, Fluorescence, Arginine Vasopressin pharmacology, Calcium
- Abstract
Intracellular calcium ([Ca2+]i) and hydrogen ion concentrations (pHi) are important regulators of cell function. Those ions also may interact and it is important, therefore, to measure their concentrations simultaneously. In the present studies we used a system developed for that purpose, a fluorescent emission ratio technique for simultaneous analysis of calcium (Indo-1) and pH (SNARF-1) in single cells at video rates, and determined if arginine vasopressin (AVP, 12.5 mumol/l) evoked [Ca2+]i and pHi signals interact in MDCK cells. We also employed a simple system for analysing the side specific (basolateral or apical) application of agonist to polarized cell layers on permeable membranes. AVP is found to evoke simultaneous changes in both pHi and [Ca2+]i. Basolateral application induced transient acidification, followed by partial recovery, and a [Ca2+]i transient with kinetic pattern similar to that of the pHi. Apical application also caused a mirror image pHi and [Ca2+]i pattern but of smaller magnitude (no peak). Selective removal of extracellular calcium ([Ca2+]e) or sodium ([Na+]e) dissociated the pHi and [Ca2+]i responses in both cases. Na+e removal abolished the pHi changes, but not the [Ca2+]i transients. [Ca2+]e removal abolished the [Ca2+]i changes and reduced, but did not abolish, the pHi responses. Thus, AVP induces pHi changes which are modified by calcium while calcium signalling is not modified by changes in pHi.
- Published
- 1996
- Full Text
- View/download PDF
32. Simultaneous imaging of intracellular [Ca2+] and pH in single cells.
- Author
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Wiegmann TB, Vamos S, Welling LW, Beatty DM, and Morris SJ
- Subjects
- Animals, Bradykinin pharmacology, Calcium metabolism, Dogs, Epithelial Cells, Epithelium chemistry, Epithelium metabolism, Hydrogen-Ion Concentration, Kidney metabolism, Male, Microscopy, Video methods, Pituitary Gland metabolism, Rats, Rats, Sprague-Dawley, Time Factors, Vasoconstrictor Agents pharmacology, Calcium analysis, Kidney chemistry, Kidney cytology, Pituitary Gland chemistry, Pituitary Gland cytology
- Published
- 1996
33. Maintenance of bradykinin-induced intracellular calcium response of MDCK cells depends on extracellular calcium.
- Author
-
Vamos S, Welling LW, and Wiegmann TB
- Subjects
- Animals, Cells, Cultured, Dogs, Kidney drug effects, Kidney metabolism, Terpenes pharmacology, Thapsigargin, Bradykinin pharmacology, Calcium metabolism
- Abstract
Bradykinin (BK) induces intracellular calcium ([Ca2+]i) release in Madin-Darby canine kidney (MDCK) cells. During long-term continuous BK exposure, cells become desensitized and fail to respond to a new BK stimulus. We used a protocol of repeated short-term BK addition and removal. MDCK cells were loaded with the Ca-indicator indo-1 and were exposed to BK (100 nmol/L) for 10 seconds, followed by BK removal. This cycle was repeated four to eight times while [Ca2+]i was continuously recorded. In a Ca-free bath, the cells gradually became completely desensitized to repeated BK stimuli. In the presence of 1 mmol/L or 10 mmol/L Cae, however, repeated addition of BK caused repeated [Ca2+]i transients with partial decrease of peak heights (327 and 436 nmol/L delta[Ca2+]i final) (partial desensitization). Repeated BK stimuli also led to partial desensitization (70% to 85%) to adenosine triphosphatase and carbachol (heterologous desensitization). BK also reduced peak thapsigargin response (70%), consistent with partial depletion of endoplasmic reticulum Ca pools. Our results show that MDCK cells maintain their sensitivity to BK during repeated short-term BK exposures. Available Ca3 plays a major role in modulating the degree of cellular responsiveness.
- Published
- 1995
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