Breaking the silence on gendered harassment and assault of community health workers: an analysis of ethnographic studies

INTRODUCTION

Across a variety of settings, women in tenuous financial circumstances are drawn to community health work as a way to advance themselves in the context of limited employment options. Female Community Health Workers (CHWs) are often preferred because they can more easily access mothers and children; at the same time, gender norms are at the heart of many of the challenges and inequities that these workers encounter. Here, we explore how these gender roles and a lack of formal worker protections leave CHWs vulnerable to violence and sexual harassment, common occurrences that are frequently downplayed or silenced.

METHODS

We are a group of researchers who work on CHW programmes in a variety of contexts globally. The examples here are drawn from our ethnographic research (participant observation and in-depth interviews).

RESULTS

CHW work creates job opportunities for women in contexts where such opportunities are extremely rare. These jobs can be a lifeline for women with few other options. Yet the threat of violence can be very real: women may face violence from the community, and some experience harassment from supervisors within health programmes.

CONCLUSION

Taking gendered harassment and violence seriously in CHW programmes is critical for research and practice. Fulfilling CHWs' vision of health programmes that value them, support them and give them opportunities may be a way for CHW programmes to lead the way in gender-transformative labour practices.

Early Lessons and Strategies from Statewide Efforts to Integrate Community Health Workers into Medicaid

The 2010 Affordable Care Act provided new impetus and funding opportunities for state Medicaid agencies to integrate community health workers (CHWs) into their health systems. Community health workers are trusted community members who participate in training so they can promote health in their own communities. This qualitative study shares lessons and strategies from Oregon's early efforts to integrate CHWs into Medicaid with concomitant financing, policy, and infrastructure issues. Key informant interviews were conducted with 16 Coordinated care organizations (CCO) and analyzed using an iterative, immersion-crystallization approach. Coordinated care organizations found CHW integration a supportive factor for Medicaid-enrolled members navigating health and social services, educating members about disease conditions, and facilitating member engagement in primary care. Barriers to CHW integration included a lack of understanding about CHW roles and their benefits to health systems, as well as a need for more intensive guidance and support on financing and integrating CHW services.

The Community Health Worker (CHW) Common Indicators Project: Engaging CHWs in Measurement to Sustain the Profession

Despite progress in documenting the outcomes of Community Health Worker interventions, the lack of standardized measures to assess CHW practice has made it difficult for programs to conduct reliable evaluations, and impossible to aggregate data across programs and regions, impeding commitment to sustainable, long-term financing of CHW programs. In addition, while CHWs have sometimes been involved as data collectors, they have seldom been engaged as full partners in all stages of evaluation and research. This manuscript details the current work being done by the CI Project, demonstrating how CHWs are able to contribute to the integrity, sustainability, and viability of CHW programs through the collaborative development and adoption of a set of common process and outcome constructs and indicators for CHW practice and CHW program implementation.

A Community Participatory Approach to Identify Common Evaluation Indicators for Community Health Worker Practice

BACKGROUND

Substantial evidence supports community health workers' (CHWs) contributions to improving health and reducing inequities. Common evaluation indicators can strengthen the evidence base and support the profession.

OBJECTIVES

We describe the development of a 6-year community-academic partnership to identify common CHW process and outcome indicators.

METHODS

Methods include interviews, focus groups and a survey conducted in Michigan, a Summit in Oregon, consultations at national conferences, and regular conference calls.

RESULTS

Using popular education as a primary strategy, we have honed our original goal, identified a set of 20 recommended constructs, developed a national constituency with international connections, and obtained dedicated funding.

CONCLUSIONS

Participatory identification, development, and uptake of a set of common indicators (CI) for CHW practice will allow data to be aggregated at multiple levels, potentially leading to more sustainable financing of CHW programs. Given that measurement drives practice, a set of common CHW indicators can help to preserve the flexibility and integrity of the CHW role.

Household water insecurity is strongly associated with food insecurity: Evidence from 27 sites in low- and middle-income countries

OBJECTIVES

Food and water insecurity have both been demonstrated as acute and chronic stressors and undermine human health and development. A basic untested proposition is that they chronically coexist, and that household water insecurity is a fundamental driver of household food insecurity.

METHODS

We provide a preliminary assessment of their association using cross-sectional data from 27 sites with highly diverse forms of water insecurity in 21 low- and middle-income countries across Africa, Asia, the Middle East, and the Americas (N = 6691 households). Household food insecurity and its subdomains (food quantity, food quality, and anxiety around food) were estimated using the Household Food Insecurity Access Scale; water insecurity and subdomains (quantity, quality, and opportunity costs) were estimated based on similar self-reported data.

RESULTS

In multilevel generalized linear mixed-effect modeling (GLMM), composite water insecurity scores were associated with higher scores for all subdomains of food insecurity. Rural households were better buffered against water insecurity effects on food quantity and urban ones for food quality. Similarly, higher scores for all subdomains of water insecurity were associated with greater household food insecurity.

CONCLUSIONS

Considering the diversity of sites included in the modeling, the patterning supports a basic theory: household water insecurity chronically coexists with household food insecurity. Water insecurity is a more plausible driver of food insecurity than the converse. These findings directly challenge development practices in which household food security interventions are often enacted discretely from water security ones.

Does volunteer community health work empower women? Evidence from Ethiopia’s Women’s Development Army

Of the millions of Community Health Workers (CHWs) serving their communities across the world, there are approximately twice as many female CHWs as there are male. Hiring women has in many cases become an ethical expectation, in part because working as a CHW is often seen as empowering the CHW herself to enact positive change in her community. This article draws on interviews, participant observation, document review and a survey carried out in rural Amhara, Ethiopia from 2013 to 2016 to explore discourses and experiences of empowerment among unpaid female CHWs in Ethiopia’s Women’s Development Army (WDA). This programme was designed to encourage women to leave the house and gain decision-making power vis-à-vis their husbands—and to use this power to achieve specific, state-mandated, domestically centred goals. Some women discovered new opportunities for mobility and self-actualization through this work, and some made positive contributions to the health system. At the same time, by design, women in the WDA had limited ability to exercise political power or gain authority within the structures that employed them, and they were taken away from tending to their individual work demands without compensation. The official rhetoric of the WDA—that women’s empowerment can happen by rearranging village-level social relations, without offering poor women opportunities like paid employment, job advancement or the ability to shape government policy—allowed the Ethiopian government and its donors to pursue ‘empowerment’ without investments in pay for lower-level health workers, or fundamental freedoms introduced into state-society relations.

Psychosocial distress among unpaid community health workers in rural Ethiopia: Comparing leaders in Ethiopia's Women's Development Army to their peers

There is a growing critical social science literature on volunteering in health programs in non-western, low-income countries, yet few have mixed quantitative and qualitative methods to examine the psychological and social wellbeing of unpaid community health workers in such contexts. We address this issue with data from unpaid community health workers (CHWs) and other women who comprise Ethiopia's state-organized Women's Development Army. We draw on qualitative and cross-sectional survey data collected between 2013 and 2016 to test links between various aspects of psychosocial and economic wellbeing and volunteer status in a rural context. We surveyed 422 adult women in Amhara state, 73 of whom were unpaid CHWs in the "Army". We also conducted interviews and focus group discussions with health officials, salaried Health Extension Workers, volunteer CHWs, and other adult women. Analyses of our qualitative and quantitative datasets show that volunteer CHWs are actually worse off than their peers in various psychosocial and economic respects, and that CHW recruitment processes are the most likely explanation for this difference. Additionally, the unpaid CHW position adds work to already burdened shoulders, and makes women-especially unmarried women-vulnerable to negative gossip and high levels of psychological distress. To a limited extent, the volunteer CHW position also bolsters married women's subjective socioeconomic status and confidence in achieving future gains in status. By showing that unpaid CHWs do not necessarily enjoy psychosocial benefits, and may experience harm as a result of their work, these findings reinforce the recommendation that CHWs in contexts of poverty be paid and better supported.

Household water sharing: A review of water gifts, exchanges, and transfers across cultures

Water sharing offers insight into the everyday and, at times, invisible ties that bind people and households with water and to one another. Water sharing can take many forms, including so-called "pure gifts," balanced exchanges, and negative reciprocity. In this paper, we examine water sharing between households as a culturally-embedded practice that may be both need-based and symbolically meaningful. Drawing on a wide-ranging review of diverse literatures, we describe how households practice water sharing cross-culturally in the context of four livelihood strategies (hunter-gatherer, pastoralist, agricultural, and urban). We then explore how cross-cutting material conditions (risks and costs/benefits, infrastructure and technologies), socio-economic processes (social and political power, water entitlements, ethnicity and gender, territorial sovereignty), and cultural norms (moral economies of water, water ontologies, and religious beliefs) shape water sharing practices. Finally, we identify five new directions for future research on water sharing: conceptualization of water sharing; exploitation and status accumulation through water sharing, biocultural approaches to the health risks and benefits of water sharing, cultural meanings and socio-economic values of waters shared; and water sharing as a way to enact resistance and build alternative economies.

Volunteers in Ethiopia's women's development army are more deprived and distressed than their neighbors: cross-sectional survey data from rural Ethiopia

BACKGROUND

Many Community Health Workers (CHWs) experience the same socioeconomic and health needs as their neighbors, given that they are by definition part of their communities. Yet very few studies aim to measure and characterize experiences of deprivation, poverty, and wellbeing among community health workers. This study quantitatively examines deprivation and wellbeing in Ethiopia's Women's Development Army (WDA), a massive unpaid community health workforce intended to improve population health and modernize the country.

METHODS

We conducted a survey of 422 volunteer WDA leaders and community members in rural Amhara state, part of a mixed-methods ethnographic study of the experiences of women in the WDA. The survey asked a variety of questions about respondents' demographics, education, assets, and access to government services. We also used survey measures to evaluate respondents' levels of household food and water security, stressful life events, social support, work burden, and psychological distress.

RESULTS

Volunteer WDA leaders and community members alike tend to have very low levels of schooling and household assets, and to be heavily burdened with daily work in several domains. Large proportions are food and water insecure, many are in debt, and many experience stretches of time with no money at all. Our survey also revealed differences between volunteer WDA leaders and other women that warrant attention. Leaders are less likely to be married and more likely to be divorced or separated. Leaders are also more likely to experience some aspects of food insecurity and report greater levels of psychological distress and more stressful life events. They also report slightly less social support than other women.

CONCLUSIONS

In rural Amhara, women who seek out and/or are sought and recruited for leader roles in the WDA are a population living in precarity. In several domains, they experience even more hardship than their neighbors. These findings highlight a need for careful attention and further research into processes of volunteer CHW selection, and to determine whether or not volunteering for CHW programs increases socioeconomic and health risks among volunteers. CHW programs in settings of poverty should stop using unpaid labor and seek to create more paid CHW jobs.

Per Diems in Polio Eradication: Perspectives From Community Health Workers and Officials

Nearly all global health initiatives give per diems to community health workers (CHWs) in poor countries for short-term work on disease-specific programs. We interviewed CHWs, supervisors, and high-level officials (n = 95) in 6 study sites across sub-Saharan Africa and South Asia in early 2012 about the per diems given to them by the Global Polio Eradication Initiative. These per diems for CHWs ranged from $1.50 to $2.40 per day. International officials defended per diems for CHWs with an array of arguments, primarily that they were necessary to defray the expenses that workers incurred during campaigns. But high-level ministry of health officials in many countries were concerned that even small per diems were unsustainable. By contrast, CHWs saw per diems as a wage; the very small size of this wage led many to describe per diems as unjust. Per diem polio work existed in the larger context of limited and mostly exploitative options for female labor. Taking the perspectives of CHWs seriously would shift the international conversation about per diems toward questions of labor rights and justice in global health pay structures.

Leptin receptor antagonism of iNKT cell function: a novel strategy to combat multiple myeloma

A hallmark of bone marrow changes with aging is the increase in adipocyte composition, but how this impacts development of multiple myeloma (MM) is unknown. Here, we report the role of the adipokine leptin as master regulator of anti-myeloma tumor immunity by modulating the invariant natural killer T (iNKT) cell function. A marked increase in serum leptin levels and leptin receptor (LR) expression on iNKT cells in MM patients and the 5T33 murine MM model was observed. MM cells and leptin synergistically counteracted anti-tumor functionality of both murine and human iNKT cells. In vivo blockade of LR signaling combined with iNKT stimulation resulted in superior anti-tumor protection. This was linked to persistent IFN-γ secretion upon repeated iNKT cell stimulation and a restoration of the dynamic antigen-induced motility arrest as observed by intravital microscopy, thereby showing alleviation of iNKT cell anergy. Overall our data reveal the LR axis as novel therapeutic target for checkpoint inhibition to treat MM.

The Global Context of Vaccine Refusal: Insights from a Systematic Comparative Ethnography of the Global Polio Eradication Initiative

Many of medical anthropology's most pressing research questions require an understanding how infections, money and ideas move around the globe. The Global Polio Eradication Initiative (GPEI) is a $9 billion project that has delivered 20 billion doses of oral polio vaccine in campaigns across the world. With its array of global activities, it cannot be comprehensively explored by the traditional anthropological method of research at one field site. This paper describes an ethnographic study of the GPEI, a collaborative effort between researchers at eight sites in seven countries. We developed a methodology grounded in nuanced understandings of local context but structured to allow analysis of global trends. Here, we examine polio vaccine acceptance and refusal to understand how global phenomena-in this case, policy decisions by donors and global health organizations to support vaccination campaigns rather than building health systems-shape local behavior. This article is protected by copyright. All rights reserved.

"Volunteers are not paid because they are priceless": community health worker capacities and values in an AIDS treatment intervention in urban Ethiopia

This article analyzes community health workers' (CHW) capacities for empathic service within an AIDS treatment program in Addis Ababa. I show how CHWs' capacities to build relationships with stigmatized people, reconcile family disputes, and confront death draw on a constellation of values, desires, and emotions encouraged by CHWs' families and religious teachings. I then examine the ways in which the capacities of CHWs were valued by the institutions that deployed them. NGO and government officials recognized that empathic care was crucial to both saving and improving the quality of people's lives. These institutional actors also defended a policy of not financially remunerating CHWs, partly by constructing their capacities as so valuable that they become "priceless" and therefore only remunerable with immaterial satisfaction. Positive change within CHW programs requires ethnographic analysis of how CHWs exercise capacities for empathic care as well as consideration of how global health institutions value these capacities.

Listening to community health workers: how ethnographic research can inform positive relationships among community health workers, health institutions, and communities

Many actors in global health are concerned with improving community health worker (CHW) policy and practice to achieve universal health care. Ethnographic research can play an important role in providing information critical to the formation of effective CHW programs, by elucidating the life histories that shape CHWs' desires for alleviation of their own and others' economic and health challenges, and by addressing the working relationships that exist among CHWs, intended beneficiaries, and health officials. We briefly discuss ethnographic research with 3 groups of CHWs: volunteers involved in HIV/AIDS care and treatment support in Ethiopia and Mozambique and Lady Health Workers in Pakistan. We call for a broader application of ethnographic research to inform working relationships among CHWs, communities, and health institutions.

The impact of polio eradication on routine immunization and primary health care: a mixed-methods study

Background. After 2 decades of focused efforts to eradicate polio, the impact of eradication activities on health systems continues to be controversial. This study evaluated the impact of polio eradication activities on routine immunization (RI) and primary healthcare (PHC).

Methods. Quantitative analysis assessed the effects of polio eradication campaigns on RI and maternal healthcare coverage. A systematic qualitative analysis in 7 countries in South Asia and sub-Saharan Africa assessed impacts of polio eradication activities on key health system functions, using data from interviews, participant observation, and document review.

Results. Our quantitative analysis did not find compelling evidence of widespread and significant effects of polio eradication campaigns, either positive or negative, on measures of RI and maternal healthcare. Our qualitative analysis revealed context-specific positive impacts of polio eradication activities in many of our case studies, particularly disease surveillance and cold chain strengthening. These impacts were dependent on the initiative of policy makers. Negative impacts, including service interruption and public dissatisfaction, were observed primarily in districts with many campaigns per year.

Conclusions. Polio eradication activities can provide support for RI and PHC, but many opportunities to do so remain missed. Increased commitment to scaling up best practices could lead to significant positive impacts.

Becoming and remaining community health workers: perspectives from Ethiopia and Mozambique

Many global health practitioners are currently reaffirming the importance of recruiting and retaining effective community health workers (CHWs) in order to achieve major public health goals. This raises policy-relevant questions about why people become and remain CHWs. This paper addresses these questions, drawing on ethnographic work in Addis Ababa, the capital of Ethiopia, between 2006 and 2009, and in Chimoio, a provincial town in central Mozambique, between 2003 and 2010. Participant observation and in-depth interviews were used to understand the life histories that lead people to become CHWs, their relationships with intended beneficiaries after becoming CHWs, and their social and economic aspirations. People in Ethiopia and Mozambique have faced similar political and economic challenges in the last few decades, involving war, structural adjustment, and food price inflation. Results suggest that these challenges, as well as the socio-moral values that people come to uphold through the example of parents and religious communities, influence why and how men and women become CHWs. Relationships with intended beneficiaries strongly influence why people remain CHWs, and why some may come to experience frustration and distress. There are complex reasons why CHWs come to seek greater compensation, including desires to escape poverty and to materially support families and other community members, a sense of deservingness given the emotional and social work involved in maintaining relationships with beneficiaries, and inequity vis-à-vis higher-salaried elites. Ethnographic work is needed to engage CHWs in the policy process, help shape new standards for CHW programs based on rooting out social and economic inequities, and develop appropriate solutions to complex CHW policy problems.

Methods for evaluating the impact of vertical programs on health systems: protocol for a study on the impact of the global polio eradication initiative on strengthening routine immunization and primary health care

Background

The impact of vertical programs on health systems is a much-debated topic, and more evidence on this complex relationship is needed. This article describes a research protocol developed to assess the relationship between the Global Polio Eradication Initiative, routine immunization, and primary health care in multiple settings.

Methods/Design

This protocol was designed as a combination of quantitative and qualitative research methods, making use of comparative ethnographies. The study evaluates the impact of the Global Polio Eradication Initiative on routine immunization and primary health care by: (a) combining quantitative and qualitative work into one coherent study design; (b) using purposively selected qualitative case studies to systematically evaluate the impact of key contextual variables; and (c) making extensive use of the method of participant observation to create comparative ethnographies of the impact of a single vertical program administered in varied contexts.

Discussion

The study design has four major benefits: (1) the careful selection of a range of qualitative case studies allowed for systematic comparison; (2) the use of participant observation yielded important insights on how policy is put into practice; (3) results from our quantitative analysis could be explained by results from qualitative work; and (4) this research protocol can inform the creation of actionable recommendations. Here, recommendations for how to overcome potential challenges in carrying out such research are presented. This study illustrates the utility of mixed-methods research designs in which qualitative data are not just used to embellish quantitative results, but are an integral component of the analysis.

Volunteerism or Labor Exploitation? Harnessing the Volunteer Spirit to Sustain AIDS Treatment Programs in Urban Ethiopia

Based on ethnographic research in Addis Ababa, Ethiopia, this paper describes NGO efforts to encourage AIDS care volunteers to eschew material returns for their labor and instead reflect on the goodness of sacrificing to promote the survival of people living with HIV/AIDS. Consensus analysis of motivational survey data collected from a sample of AIDS care volunteers (n=110) suggests that they strongly share a sacrificial and prosocial motivational model. These results may be explained by several factors, including the efforts of the organizations to shape volunteers' motivations, the self-selection of volunteers, positive reinforcement in seeing one's patients become healthy, and social desirability bias. In-depth interviews examining the motivations and behaviors of volunteers reveal a more complicated picture: even ostensibly devoted and altruistic volunteers strongly question their service commitments. The complexity and ambivalence of volunteers' motivations reflect the profound uncertainty that they face in achieving improved socioeconomic status for themselves and their families amid widespread unemployment and sharply rising food prices. Their desires for economic opportunities explain why local NGOs exert so much effort to shape and sustain-and yet fail to completely control-their motivations. This recasts economically-insecure volunteers' consent to donate their labor as a process of negotiation with their organizers. Future research should explore how models of health care volunteerism and volunteer motivations are shaped by individual and collective experiences in political-economic context.

CYCLES OF POVERTY, FOOD INSECURITY, AND PSYCHOSOCIAL STRESS AMONG AIDS CARE VOLUNTEERS IN URBAN ETHIOPIA

With the rollout of AIDS therapies, volunteer AIDS care has been promoted across Africa under the assumption that volunteerism is economically imperative in settings of health professional and resource scarcity. As low-income volunteers have become a major part of HIV/AIDS prevention and treatment workforces, it is imperative to question how poverty impacts their well-being. This chapter presents epidemiologic data collected during the 2008 food crisis from a sample of 110 AIDS care volunteers in Addis Ababa, Ethiopia, as well as narratives offered by HIV-positive volunteers, highlighting a widely overlooked way in which food insecurity and mental distress impact efforts to treat AIDS in sub-Saharan Africa. Food insecurity and elevated common mental disorder (CMD) symptom loads were common and tightly linked among the volunteers in the sample. Volunteers who were HIV-positive (17 percent) fared slightly worse in terms of food insecurity and psychosocial well-being. However, positive HIV serostatus was not associated with CMD in multivariate analyses accounting for food insecurity. Narratives illustrate how being HIV-positive shaped experiences of psychosocial stress, which involved unemployment and lack of prospects for marital relationships or strife within them. Our focus demonstrates the potential for mixing ethnographic and epidemiological methods to inform policy questions regarding poverty-reduction through compensation for volunteers' valuable labor, as well as AIDS care program sustainability. [volunteerism, AIDS care, food insecurity, livelihoods, HIV, psychosocial health].

Critical aspects for the reliable headspace analysis of plants cultivated in vitro

Various factors controlling the recoveries of volatile organic compounds in vitro headspace analysis of tomato plants (Lycopersicon esculentum Mill. 'Moneymaker'), sampled using solid phase micro-extraction, were evaluated and optimised. The variations in composition of the headspaces were determined as a function of time, and following in vitro wounding of the plant.

Mapping of the ATP-binding sites on inositol 1,4,5-trisphosphate receptor type 1 and type 3 homotetramers by controlled proteolysis and photoaffinity labeling

Submillimolar ATP concentrations strongly enhance the inositol 1,4,5-trisphosphate (IP(3))-induced Ca(2+) release, by binding specifically to ATP-binding sites on the IP(3) receptor (IP(3)R). To locate those ATP-binding sites on IP(3)R1 and IP(3)R3, both proteins were expressed in Sf9 insect cells and covalently labeled with 8-azido-[alpha-(32)P]ATP. IP(3)R1 and IP(3)R3 were then purified and subjected to a controlled proteolysis, and the labeled proteolytic fragments were identified by site-specific antibodies. Two fragments of IP(3)R1 were labeled, each containing one of the previously proposed ATP-binding sites with amino acid sequence GXGXXG (amino acids 1773-1780 and 2016-2021, respectively). In IP(3)R3, only one fragment was labeled. This fragment contained the GXGXXG sequence (amino acids 1920-1925), which is conserved in the three IP(3)R isoforms. The presence of multiple interaction sites for ATP was also evident from the IP(3)-induced Ca(2+) release in permeabilized A7r5 cells, which depended on ATP over a very broad concentration range from micromolar to millimolar.

Effects of the immunosuppressant FK506 on intracellular Ca2+ release and Ca2+ accumulation mechanisms

The immunophilin FKBP12 associates with intracellular Ca2+ channels and this interaction can be disrupted by the immunosuppressant FK506. We have investigated the effect of FK506 on Ca2+ release and Ca2+ uptake in permeabilized cell types. Changes in medium free [Ca2+] were detected by the fluorescent Ca2+ indicator fluo-3 in digitonin-permeabilized SH-SY5Y human neuroblastoma cells, DT40 and R23-11 (i.e. triple inositol 1,4,5-trisphosphate (IP3) receptor knockout cells) chicken B lymphocytes and differentiated and undifferentiated BC3H1 skeletal muscle cells. 45Ca2+ fluxes were studied in saponin-permeabilized A7r5 rat smooth muscle cells. Addition of FK506 to permeabilized SH-SY5Y cells led to a sustained elevation of the medium [Ca2+] corresponding to approximately 30 % of the Ca2+ ionophore A23187-induced [Ca2+] rise. This rise in [Ca2+] was not dependent on mitochondrial activity. This FK506-induced [Ca2+] rise was related to the inhibition of the sarcoplasmic/endoplasmic reticulum Ca2+-Mg2+-ATPase (SERCA) Ca2+ pump. Oxalate-facilitated 45Ca2+ uptake in SH-SY5Y microsomes was inhibited by FK506 with an IC50 of 19 microM. The inhibition of the SERCA Ca2+ pump was not specific since several macrocyclic lactone compounds (ivermectin > FK506, ascomycin and rapamycin) were able to inhibit Ca2+ uptake activity. FK506 (10 microM) did not affect IP3-induced Ca2+ release in permeabilized SH-SY5Y and A7r5 cells, but enhanced caffeine-induced Ca2+ release via the ryanodine receptor (RyR) in differentiated BC3H1 cells. In conclusion, FK506 inhibited active Ca2+ uptake by the SERCA Ca2+ pump; in addition, FK506 enhanced intracellular Ca2+ release through the RyR, but it had no direct effect on IP3-induced Ca2+ release.

Differential modulation of inositol 1,4,5-trisphosphate receptor type 1 and type 3 by ATP

Binding of ATP to the inositol 1,4,5-trisphosphate receptor (IP(3)R) results in a more pronounced Ca(2+)release in the presence of inositol 1,4,5-trisphosphate (IP(3)). Two recently published studies demonstrated a different ATP sensitivity of IP(3)-induced Ca(2+)release in cell types expressing different IP(3)R isoforms. Cell types expressing mainly IP(3)R3 were less sensitive to ATP than cell types expressing mainly IP(3)R1 (Missiaen L, Parys JB, Sienaert I et al. Functional properties of the type 3 InsP(3)receptor in 16HBE14o- bronchial mucosal cells. J Biol Chem 1998;273: 8983-8986; Miyakawa T, Maeda A, Yamazawa T et al. Encoding of Ca(2+)signals by differential expression of IP(3)receptor subtypes. EMBO J 1999;18: 1303-1308). In order to investigate the difference in ATP sensitivity between IP(3)R isoforms at the molecular level, microsomes of Sf9 insect cells expressing full-size IP(3)R1 or IP(3)R3 were covalently labeled with ATP by using the photoaffinity label 8-azido[alpha-(32)P]ATP. ATP labeling of the IP(3)R was measured after immunoprecipitation of IP(3)Rs with isoform-specific antibodies, SDS-PAGE and Phosphorimaging. Unlabeled ATP inhibited covalent linking of 8-azido[alpha-(32)P]ATP to the recombinant IP(3)R1 and IP(3)R3 with an IC(50)of 1.6 microM and 177 microM, respectively. MgATP was as effective as ATP in displacing 8-azido[alpha-(32)P]ATP from the ATP-binding sites on IP(3)R1 and IP(3)R3, and in stimulating IP(3)-induced Ca(2+)release from permeabilized A7r5 and 16HBE14o- cells. The interaction of ATP with the ATP-binding sites on IP(3)R1 and IP(3)R3 was different from its interaction with the IP(3)-binding domains, since ATP inhibited IP(3)binding to the N-terminal 581 amino acids of IP(3)R1 and IP(3)R3 with an IC(50)of 353 microM and 4.0 mM, respectively. The ATP-binding sites of IP(3)R1 bound much better ATP than ADP, AMP and particularly GTP, while IP(3)R3 displayed a much broader nucleotide specificity. These results therefore provide molecular evidence for a differential regulation of IP(3)R1 and IP(3)R3 by ATP.

Mapping of IP(3)-mediated Ca(2+) signals in single human neuroblastoma SH-SY5Y cells: cell volume shaping the Ca(2+) signal

Fast confocal laser-scanning microscopy was used to study spatiotemporal properties of IP(3)-mediated Ca(2+) release signals in human SH-SY5Y neuroblastoma cells. [Ca(2+)](i) increases were not affected by ryanodine (30 microgM) or caffeine (10 mM) and largely insensitive to removal of external Ca(2+), indicating predominance of IP(3)-induced Ca(2+) release. Ca(2+) signals evoked by high concentration (10 microM) of the muscarinic agonist carbachol appeared as self-propagating waves initiating in cell processes. At low carbachol concentrations (500 nM) Ca(2+) changes in most cells displayed striking spatiotemporal heterogeneity. The Ca(2+) response in the cell body was delayed and had a smaller amplitude and a slower rise time than that in processes. Ca(2+) changes in processes either occurred in a homogeneous manner throughout the whole process or were sometimes confined to hot spots. Regional differences in surface-to-volume ratio appear to be critical clues that determine the spatiotemporal pattern of intracellular Ca(2+) release signals.

Adenine-nucleotide binding sites on the inositol 1,4,5-trisphosphate receptor bind caffeine, but not adenophostin A or cyclic ADP-ribose

Binding of ATP to the inositol 1,4,5-trisphosphate receptor (IP3R) results in a more pronounced Ca2+ release in the presence of inositol 1,4,5-trisphosphate (IP3). We have expressed the cDNAs encoding two putative adenine-nucleotide binding sites of the neuronal form of IP3R-1 as glutathione S-transferase (GST)-fusion proteins in bacteria. Specific [alpha-32P]ATP binding was observed for the two GST-fusion proteins, representing aa 1710-1850 and aa 1944-2040 of IP3R-1. The ATP-binding sites in both fusion proteins had the same nucleotide specificity as found for the intact IP3R (ATP > ADP > AMP > GTP). Smaller GST-fusion proteins (aa 1745-1792 and aa 2005-2023) displayed a much weaker ATP-binding activity. CoA, which also potentiated IP3-induced Ca2+ release in A7r5 cells, interacted with the ATP-binding sites on the fusion proteins. Such interaction was not observed for 1,N6-etheno CoA and 3'-dephospho-CoA, which are much less effective in potentiating IP3-induced Ca2+ release. Since the adenine-containing compounds adenophostin A, caffeine and cyclic ADP-ribose modulate IP3-induced Ca2+ release, a possible effect of these compounds on the ATP-binding sites was examined. ATP stimulated adenophostin A- and IP3-induced Ca2+ release in A7r5 cells with an EC50 of respectively 21 and 20 microM. Also the threshold concentration of ATP for stimulating the release was similar for the two agonists. Adenophostin A (100 microM) and cyclic ADP-ribose (100 microM) were ineffective in displacing [alpha-32P]ATP from the binding sites of both GST-fusion proteins. Caffeine (50 mM), however, inhibited [alpha-32P]ATP binding to both fusion proteins by more than 50%. These data provide evidence for a direct interaction of caffeine but not of adenophostin A or cyclic ADP-ribose with the adenine-nucleotide binding sites of the IP3R.

A cystine lower pole renal calculus treated with holmium: YAG laser using a flexible 9,5F transurethral ureteroscope

We report a case of a 1.5 cm cystine staghorn calculus of the right lower pole in a 32 year female known cystinuric patient. With a 200 microns Holmium laser probe through a 9,5 F flexible ureteroscope the calculus was fragmented in small particles. An internal ureteral stent was inserted at the end of the procedure. All but one small residual fragments were evacuated spontaneously after removal of the stent. This case shows that flexible ureteroscopy combined with the Holmium laser is a safe and efficient procedure to treat medium size renal cystine calculi. It can be repeated in case of recurrence with minimal trauma to the urologic tract.

Functional properties of the type-3 InsP3 receptor in 16HBE14o- bronchial mucosal cells

The type-3 inositol 1,4,5-trisphosphate (InsP3) receptor is the major isoform expressed in 16HBE14o- cells from bronchial mucosa, representing 93% at the mRNA level as determined by ratio reverse transcription-polymerase chain reaction and about 81% at the protein level as determined with isoform-specific antibodies (Sienaert, I., Huyghe, S., Parys, J. B., Malfait, M., Kunzelmann, K., De Smedt, H., Verleden, G. M., and Missiaen, L., Pflügers Arch. Eur. Y. Physiol., in press). The present 45Ca2+ efflux experiments indicate that these InsP3 receptors were 3 times less sensitive to InsP3 and 11 times less sensitive to ATP than those in A7r5 cells, where the type-1 InsP3 receptor is the main isoform. ATP did not increase the cooperativity of the InsP3-induced Ca2+ release in 16HBE14o- cells, in contrast to its effect in A7r5 cells. The sulfhydryl reagent thimerosal also did not stimulate InsP3-induced Ca2+ release in 16HBE14o- cells, again in contrast to its effect in A7r5 cells. Adenophostin A was more potent than InsP3 in stimulating the release in both cell types. The biphasic activation of the InsP3 receptor by cytosolic Ca2+ occurred in both cell types. We conclude that Ca2+ release mediated by the type-3 InsP3 receptor mainly differs from that mediated by the type-1 InsP3 receptor by its lack of stimulation by sulfhydryl oxidation and its lower ATP and InsP3 sensitivity. The predominant expression of the type-3 InsP3 receptor in the bronchial mucosa may be part of a mechanism coping with oxidative stress in that tissue.

Inhibition of inositol trisphosphate-induced calcium release by cyclic ADP-ribose in A7r5 smooth-muscle cells and in 16HBE14o- bronchial mucosal cells

Ca2+ release from intracellular stores occurs via two families of intracellular channels, each with their own specific agonist: Ins(1, 4,5)P3 for the Ins(1,4,5)P3 receptor and cyclic ADP-ribose (cADPR) for the ryanodine receptor. We now report that cADPR inhibited Ins(1, 4,5)P3-induced Ca2+ release in permeabilized A7r5 cells with an IC50 of 20 microM, and in permeabilized 16HBE14o- bronchial mucosal cells with an IC50 of 35 microM. This inhibition was accompanied by an increase in specific [3H]Ins(1,4,5)P3 binding. 8-Amino-cADPR, but not 8-bromo-cADPR, antagonized this effect of cADPR. The inhibition was prevented by a whole series of inositol phosphates (10 microM) that did not affect Ins(1,4,5)P3-induced Ca2+ release, and by micromolar concentrations of PPi and various nucleotide di- or triphosphates. We propose that cADPR must interact with a novel regulatory site on the Ins(1,4,5)P3 receptor or on an associated protein. This site is neither the Ins(1,4,5)P3-binding domain, which prefers Ins(1,4,5)P3 and only binds nucleotides and PPi in the millimolar range, nor the stimulatory adenine nucleotide binding site.

Synergism between hypotonically induced calcium release and fatty acyl-CoA esters induced calcium release from intracellular stores

The non-mitochondrial Ca2+ stores in permeabilized A7r5 cells responded to a decrease in Mg-ATP concentration with a pronounced Ca2+ release if 20 microM CoA was present. This release was rather specific for the preincubation or removal of ATP. ATP gamma S was much less effective and AMP-PNP, GTP, ITP, CTP, UTP, ADP, AMP, adenosine and adenine had no effect. CoA activated with an EC50 of 6 microM. Dephospho-CoA was a less effective cofactor and desulfo-CoA was ineffective. The release induced by Mg-ATP removal did not occur in the presence of 2% fatty acid-free bovine serum albumin and did not develop at 4 degrees C. All these findings suggest that CoA had to be acylated by endogenous fatty-acyl-CoA synthetase to become effective. Myristoyl- and palmitoyl-CoA esters were identified as the most effective cofactors for the release. Ca2+ release induced by removing Mg-ATP did not occur if the osmolality of the medium was kept constant by addition of mannitol, sucrose, KCl, MgCl2 or Mg-GTP, indicating that the decrease in tonicity was the trigger for the release. Mg-ATP plus CoA also synergized with Ca2+ release induced by a hypotonic shock imposed by diluting the medium with H2O. Osmolality changes induced by decreasing the Mg-ATP concentration were more effective in releasing Ca2+ than equal decreases in concentration of all solutes. We conclude that fatty acyl-CoA esters sensitize the hypotonically induced Ca2+ release from the non-mitochondrial Ca2+ stores.

Effect of adenine nucleotides on myo-inositol-1,4,5-trisphosphate-induced calcium release

The effects of a whole series of adenine nucleotides on Ins(1,4,5)P3-induced Ca2+ release were characterized in permeabilized A7r5 smooth-muscle cells. Several adenine nucleotides activated the Ins(1, 4,5)P3 receptor. It was observed that 3'-phosphoadenosine 5'-phosphoulphate, CoA, di(adenosine-5')tetraphosphate (Ap4A) and di(adenosine-5')pentaphosphate (Ap5A) were more effective than ATP. Ap4A and Ap5A also interacted with a lower EC50 than ATP. In order to find out how these adenine nucleotides affected Ins(1,4, 5)P3-induced Ca2+ release, we have measured their effect on the response of permeabilized A7r5 cells to a progressively increasing Ins(1,4,5)P3 concentration. Stimulatory ATP and Ap5A concentrations had no effect on the threshold Ins(1,4,5)P3 concentration for initiating Ca2+ release, but they stimulated Ca2+ release in the presence of supra-threshold Ins(1,4,5)P3 concentrations by increasing the co-operativity of the release process. Inhibition of the Ins(1,4,5)P3-induced Ca2+ release at higher ATP concentrations was associated with a further increase in co-operativity and also with a shift in threshold towards higher Ins(1,4,5)P3 concentrations. ATP had no effect on the non-specific Ca2+ leak in the absence of Ins(1,4,5)P3. We conclude that the adenine-nucleotide-binding site can be activated by many different adenine nucleotides. Binding of these compounds to the transducing domain of the Ins(1,4,5)P3 receptor increases the efficiency of transmitting Ins(1,4,5)P3 binding to channel opening. The inhibition by high ATP concentrations is exerted at a different site, related to Ins(1,4,5)P3 binding.

The use of a secondary cathode to analyse solid non-conducting samples with direct current glow discharge mass spectrometry: potential and restrictions

A direct current glow discharge mass spectrometer has been used to analyse solid non-conducting samples: glass, polycarbonate, marble, aluminium oxide and Teflon. This is made possible by the use of a so-called secondary cathode. The methodology of this concept is investigated and analytical figures of merit are presented.

A new device for the fixation of unstable pertrochanteric fractures of the hip

A new type of fixation device for the treatment of pertrochanteric fractures of the hip is described. The device has an axial-compression screw to allow compression along an axis parallel to the femoral shaft. As the fracture settles postoperatively, dynamic axial compression continues. This axial-compression device was used in twenty-five patients who had an unstable intertrochanteric or proximal subtrochanteric fracture of the proximal part of the femur. The average extent of axial impaction or settling was five millimeters (standard deviation, 1.3 millimeters) at the most recent follow-up examination, and the relationship between the femoral head and shaft was altered less than with the use of a conventional compression screw-plate device. A larger proportion of the patients who had the new device were able to walk fifteen meters (fifty feet) independently by the time of discharge from the hospital, even though they left the hospital earlier. No technical failures were seen in the patients who were treated with the axial-compression screw device. We believe that the axial-compression screw-plate device is appropriate for the treatment of unstable pertrochanteric fractures of the hip.