Psychosocial interventions to improve the mental health of survivors of human trafficking: a realist review

More than 50 million people globally are subjected to modern slavery and human trafficking. Adverse mental health consequences of extreme exploitation are prevalent and often severe. We conducted a systematic and realist review on evaluations of psychosocial interventions for survivors of human trafficking. The review aimed to identify the influence of these interventions on the mental health and wellbeing of trafficked people and examine how they worked for which survivors in which contexts. We searched eight databases (MEDLINE, MEDLINE In-Process, Embase, PsycINFO, Global Health, CINAHL Plus, Web of Science, and Cochrane) for published evaluations of psychosocial interventions for survivors of human-trafficking. We followed a realist approach to analyse the data and report on the limitations of the studies identified. We identified four mechanisms of change as being triggered by the various intervention activities: (1) awareness and understanding; (2) trust, safety, and security; (3) agency, autonomy, empowerment, and social connections; and (4) self-reflection, self-expression, and self-care. Improving mental health after traumatic events is an ongoing, nonlinear process. Intervention effectiveness and transferability would benefit from more transparent programme theories and well articulated assumptions that identify the pathways to change.

Corrigendum: Human trafficking: Results of a 5-year theory-based evaluation of interventions to prevent trafficking of women from South Asia

[This corrects the article DOI: 10.3389/fpubh.2021.645059.].

Mechanisms for the prevention of adolescent intimate partner violence: A realist review of interventions in low- and middle-income countries

Adolescent girls are among those at the greatest risk of experiencing intimate partner violence (IPV). Despite adolescence being widely regarded as a window of opportunity to influence attitudes and behaviours related to gender equality, evidence on what works to prevent IPV at this critical stage is limited outside of high-income, school-based settings. Even less is understood about the mechanisms of change in these interventions. We conducted a realist review of primary prevention interventions for adolescent IPV in low- and middle-income countries (LMICs) to synthesise evidence on how they work, for whom, and under which circumstances. The review took place in four iterative stages: 1) exploratory scoping, 2) developing initial programme theory, 3) systematic database search, screening and extraction, and 4) purposive searching and refinement of programme theory. We identified eleven adolescent IPV prevention interventions in LMICs, most of which demonstrated a positive impact on IPV experience and/or perpetration (n = 10). Most interventions (n = 9) implemented school- or community-based interactive peer-group education to transform attitudes and norms around gender and relationships for behaviour change. The central mechanism of change related to gender transformative content prompting adolescents to critically reflect on their attitudes and relationships, leading to a reconceptualisation of their values and beliefs. This central mechanism was supported by two secondary implementation mechanisms: 1) the design and delivery of interventions: interactive, age-appropriate education delivered in peer-groups provided adolescents a safe space to engage with content and build communication skills, and 2) the target group: social norms interventions targeting the wider community created enabling environments supportive of individual change. This review highlights the immense potential of gender transformative interventions during the critical period of adolescence for IPV prevention. Future interventions should consider the broader drivers of adolescent IPV and ensure intersectionality informed approaches to maximise their potential to capitalise on this window of opportunity.

"I had tears in my eyes but I just left without looking back". A qualitative study of migration-related stressors amongst Nepali male labour migrants

Labour migration has become a crucial livelihood strategy in settings where employment options are limited. Such opportunities come with potential benefits but also introduce stressors. This study explores migration-related stressors amongst returnee male Nepali international labour migrants. We conducted a qualitative study in Kathmandu amongst 42 returnee male international labour migrants. We explored migration decisions, processes, experiences in destination and on return. The participants worked in low- and semi-skilled jobs in Malaysia, Qatar, and Saudi Arabia. Men reported stressors representing five broad areas: workplace/employer, family, recruitment, environment and legal. Most belonged to the workplace/employer category such as exploitative practices of document confiscation, contract discrepancies and poor working conditions. Family stressors were often due to disagreements about whether to migrate, and once in destination, being absent during illness and death in the family. Recruitment stressors were linked to the migration process and costs. Environmental stressors included over-crowdedness and poor hygiene, and poor security at the accommodation and in the wider town. Legal stressors were related to the lack of documentation, and negative encounters with the local police. Multiple stressors were often experienced simultaneously or in succession. Male labour migrants from Nepal who had worked in various countries and job-sectors reported multiple types of stress. The majority of stressors belong to the workplace category, where migrants may have limited power to challenge problems with their employers. The cumulative effect of such experiences may negatively impact on migrants' wellbeing. Future research should explore migrants' ability to cope with the many stressors encountered.

P-745 The efficacy of Buscopan® in reducing pain during ultrasound-guided manual vacuum aspiration (USG-MVA): A double-blind randomised placebo-controlled trial

Study question

Does Buscopan® reduce abdominal pain experienced by women undergoing ultrasound-guided manual vacuum aspiration (USG-MVA)?

Summary answer

The addition of 20mg Buscopan® intravenous injection was not associated with a statistical reduction in pain score but leads to a higher patient satisfaction score.

What is known already

Ultrasound-guided Manual Vacuum aspiration is a feasible and effective out-patient treatment option for treating early pregnancy loss. However, it is associated with a moderate amount of pain due to uterine contraction.

Study design, size, duration

This randomised, double-blinded, placebo-controlled trial was conducted in a university-affiliated tertiary hospital. The study assessed whether 1 ml of 20mg Buscopan® intravenous injection 5 minutes before the USG-MVA will reduce the abdominal pain experienced by the women immediately and 2 hours after the procedure. Participants were randomised between June 2018 to January 2020 using a computer-generated number series in a 1:1 ratio.

Participants/materials, setting, methods

Women aged 18 years or older with first-trimester miscarriage undergoing the USG-MVA procedure were eligible. In total, 122 participants out of 128 eligible were included. Of whom, 111 underwent the USG-MVA procedure, 60 randomised to the Buscopan® group, and 62 to the placebo group.

Main results and the role of chance

The median abdominal pain scores in the Buscopan® group were 16.0% and 21.2% lower than the placebo group immediately post-procedure and 2 hours after the procedure in the Buscopan® group. Repeated measures ANOVA indicated that the both vaginal and abdominal pain scores improved significantly with the time (Vaginal F(1,108)= 180.1,p<0.0001;

Abdominal

F(1,108)=83.41,p<0.001) but not with group. No difference was noted in the complications and side effects profile. The physiological stress measured by Log10 sAA levels reduced significantly with time (F(2.8,286.1)= 6.3, p < 0.001) but not with group (F = 0.1, p = 0.96). Women randomised to Buscopan® had a significantly higher (p = 0.032) mean VAS satisfaction scores compared to those receiving placebo (79.0±17.3 vs 73.4±24.1).

Limitations, reasons for caution

This study was a single-centre study, thus one should be cautious in the overall generalisability of the results.

Wider implications of the findings

Few studies have evaluated the use of anti-spasmodic agents to minimise uterine contraction pain in women undergoing outpatient uterine evacuation. We consider Buscopan® a useful adjunct in the pain control of USG-MVA to specifically reduce uterine cramps. Further larger studies are required to evaluate its efficacy

Trial registration number

ChiCTR1800014590

P–745 The efficacy of Buscopan® in reducing pain during ultrasound-guided manual vacuum aspiration (USG-MVA): A double-blind randomised placebo-controlled trial

Study question

Does Buscopan® reduce abdominal pain experienced by women undergoing ultrasound-guided manual vacuum aspiration (USG-MVA)?

Summary answer

The addition of 20mg Buscopan® intravenous injection was not associated with a statistical reduction in pain score but leads to a higher patient satisfaction score.

What is known already

Ultrasound-guided Manual Vacuum aspiration is a feasible and effective out-patient treatment option for treating early pregnancy loss. However, it is associated with a moderate amount of pain due to uterine contraction.

Study design, size, duration

This randomised, double-blinded, placebo-controlled trial was conducted in a university-affiliated tertiary hospital. The study assessed whether 1 ml of 20mg Buscopan® intravenous injection 5 minutes before the USG-MVA will reduce the abdominal pain experienced by the women immediately and 2 hours after the procedure. Participants were randomised between June 2018 to January 2020 using a computer-generated number series in a 1:1 ratio.

Participants/materials, setting, methods

Women aged 18 years or older with first-trimester miscarriage undergoing the USG-MVA procedure were eligible. In total, 122 participants out of 128 eligible were included. Of whom, 111 underwent the USG-MVA procedure, 60 randomised to the Buscopan® group, and 62 to the placebo group.

Main results and the role of chance

The median abdominal pain scores in the Buscopan® group were 16.0% and 21.2% lower than the placebo group immediately post-procedure and 2 hours after the procedure in the Buscopan® group. Repeated measures ANOVA indicated that the both vaginal and abdominal pain scores improved significantly with the time (Vaginal F(1,108)=180.1,p<0.0001; Abdominal: F(1,108)=83.41,p<0.001) but not with group. No difference was noted in the complications and side effects profile. The physiological stress measured by Log10 sAA levels reduced significantly with time (F(2.8,286.1)= 6.3, p < 0.001) but not with group (F = 0.1, p = 0.96). Women randomised to Buscopan® had a significantly higher (p = 0.032) mean VAS satisfaction scores compared to those receiving placebo (79.0±17.3 vs 73.4±24.1).

Limitations, reasons for caution

This study was a single-centre study, thus one should be cautious in the overall generalisability of the results.

Wider implications of the findings: Few studies have evaluated the use of anti-spasmodic agents to minimise uterine contraction pain in women undergoing outpatient uterine evacuation. We consider Buscopan® a useful adjunct in the pain control of USG-MVA to specifically reduce uterine cramps. Further larger studies are required to evaluate its efficacy.

Trial registration number

ChiCTR1800014590

Coping with migration-related stressors - a qualitative study of Nepali male labour migrants

Background

International labour migration has become a crucial livelihood strategy, especially in countries where decently paid employment opportunities are limited. Such opportunities come with many potential benefits but also many stressors that challenge migrants’ coping skills, especially when they are in a foreign environment away from their normal support network. This paper explores how labour migrants coped with migration-related stressors using a sample of male Nepali migrants.

Methods

Qualitative life histories were conducted in Kathmandu among returnee male migrants. Coping responses were categorised based Skinner and Zimmer-Gembeck’s coping typologies. The interview scripts were transcribed in Nepali and translated into English for analysis. Each interview script was open coded and then categorised according to the 12 core coping families. Data were analysed thematically to explore relationships across and within coping and stressors.

Results

Forty-two men were interviewed who mainly worked in low- and semi-skilled jobs in Malaysia, and the Gulf States. The coping strategies most commonly used belonged to the families of problem-solving, support-seeking, negotiation and helplessness. Men used these either individually or collectively with other migrants. Those who sought assistance from authorities or civil society organisations did not always receive the help needed and there were mixed messages as to when and what types of assistance were available. Some stressors involved multiple coping strategies simultaneously, others described changing strategies following unsuccessful earlier attempts. The coping families of helplessness and social isolation reflected migrants’ limited power in challenging certain stressors. The choice of coping strategies was also moderated by factors such as outstanding loans, language difficulties, or not wanting to cause their family distress. Some coping strategies used led to  new stressors.

Conclusions

Migrants need greater clarifications on their rights with respect to contract discrepancies, the types of support available, how and from whom to access them once in destination. Improvements to the support mechanisms migrants can access as well as strengthening migrant-led initiatives in destination countries to support labour migrants' in managing stressors are needed. These may contribute to reducing the experiences and impact of such stressors, which may ultimately lead to more successful migration outcomes. As labour migration from Nepal is likely to continue, government and CSOs need to ensure migrants have the support they need to cope with the challenges they may encountered along the way.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11192-y.

Human Trafficking: Results of a 5-Year Theory-Based Evaluation of Interventions to Prevent Trafficking of Women From South Asia

Preventing modern slavery is of global interest, but evidence on interventions remains weak. This paper presents findings from a 5-year theory-based evaluation of an empowerment and knowledge-building intervention to prevent the exploitation of South Asian female migrant workers. The evaluation used realist evaluation techniques to examine the intervention mechanisms, outcomes, and context. Findings from qualitative and quantitative data from Nepal, India, and Bangladesh indicate that the intervention mechanisms (trainings) were not well-targeted, not delivered by appropriate trainers, and did not address participants' expectations or concerns. The outcomes of empowerment and migration knowledge were not achieved due to poor integration of context-related factors, flawed assumptions about the power inequalities, including barriers preventing women from asserting their rights. Ultimately, interventions to prevent exploitation of migrant workers should be developed based on strong evidence about the social, political, and economic realities of their migration context, especially in destination settings.

Challenges to pre-migration interventions to prevent human trafficking: Results from a before-and-after learning assessment of training for prospective female migrants in Odisha, India

Background

Awareness-raising and pre-migration training are popular strategies to prevent human trafficking. Programmatic theories assume that when prospective migrants are equipped with information about risks, they will make more-informed choices, ultimately resulting in safe migration. In 2016, India was estimated to have 8 million people in modern slavery, including those who migrate internally for work. Work in Freedom (WiF) was a community-based trafficking prevention intervention. This study evaluated WiF’s pre-migration knowledge-building activities for female migrants in Odisha to prevent future labour-related exploitation.

Methods

Pre- and post- training questionnaires were administered to women (N = 347) who participated in a two-day pre-migration training session. Descriptive analysis and unadjusted analyses (paired t-tests, McNemar’s tests, Wilcoxon signed ranks tests) examined differences in women’s knowledge scores before and after training. Adjusted analyses used mixed effects models to explore whether receiving information on workers’ rights or working away from home prior to the training was associated with changes in scores. Additionally, we used data from a household survey (N = 4,671) and survey of female migrants (N = 112) from a population sample in the same district to evaluate the intervention’s rationale and implementation strategy.

Results

Female participants were on average 37.3 years-old (SD 11) and most (67.9%) had no formal education. Only 11 participants (3.2%) had previous migration experience. Most participants (90.5%) had previously received information or advice on workers’ rights or working away from home. Compared to female migrants in the population, training participants were different in age, caste and religion. Awareness about migration risks, rights and collective bargaining was very low initially and remained low post-training, e.g. of 13 possible migration risks, before the training, participants named an average of 1.2 risks, which increased only slightly to 2.1 risks after the training (T(346) = -11.64, p<0.001). Changes were modest for attitudes about safe and risky migration practices, earnings and savings. Before the training, only 34 women (10.4%) considered migrating, which reduced to 25 women (7.7%) post-training (X² = 1.88, p = 0.169)—consistent with the low prevalence (7% of households) of female migration locally. Women’s attitudes remained relatively fixed about the shame associated with paid domestic work. Survey data indicated focusing on domestic work did not correspond to regional migration trends, where women migrate primarily for construction or agriculture work.

Conclusion

The apparent low effectiveness of the WiF short-duration migration training may be linked to the assumption that individual changes in knowledge will lead to shifts in social norms. The narrow focus on such individual-level interventions may overestimate an individual’s agency. Findings indicate the importance of intervention development research to ensure activities are conducted in the right locations, target the right populations, and have relevant content. Absent intervention development research, this intervention suffered from operating in a site that had very few migrant women and a very small proportion migrating for domestic work—the focus of the training. To promote better development investments, interventions should be informed by local evidence and subjected to rigorous theory-based evaluation to ensure interventions achieve the most robust design to foster safe labour migration for women.

Virtual reality for acute pain in outpatient hysteroscopy: a randomised controlled trial

OBJECTIVE

To evaluate the effectiveness of virtual reality as a distraction technique in the management of acute pain and anxiety during outpatient hysteroscopy.

DESIGN

Parallel group, prospective randomised controlled trial.

SETTING

UK University Hospital.

METHODS

Forty consenting, eligible women were randomised to virtual reality intervention (immersive video content as a distraction method) or standard care during outpatient hysteroscopy from August to October 2018.

MAIN OUTCOME MEASURES

Pain and anxiety outcomes were measured as a numeric rating score (scale 0-10).

RESULTS

Compared with standard care, women with virtual reality intervention experienced less average pain (score 6.0 versus 3.7, mean difference 2.3, 95% CI 0.61-3.99, P = 0.009) and anxiety (score 5.45 versus 3.3, mean difference 2.15, 95% CI 0.38-3.92, P = 0.02).

CONCLUSION

Virtual reality was effective in reducing pain and anxiety during outpatient hysteroscopy in a mixed-methods randomised control trial. Its wide potential role in ambulatory gynaecological procedures needs further evaluation.

TWEETABLE ABSTRACT

Virtual reality can be used as a part of a multimodal strategy to reduce acute pain and anxiety in patients undergoing outpatient hysteroscopy.

HIV-1 Gag specifically restricts PI(4,5)P2 and cholesterol mobility in living cells creating a nanodomain platform for virus assembly

HIV-1 Gag protein assembles at the plasma membrane of infected cells for viral particle formation. Gag targets lipids, mainly PI(4,5)P2, at the inner leaflet of this membrane. Here, we address the question whether Gag is able to trap specifically PI(4,5)P2 or other lipids during HIV-1 assembly in the host CD4+ T lymphocytes. Lipid dynamics within and away from HIV-1 assembly sites were determined using super-resolution microscopy coupled with scanning fluorescence correlation spectroscopy in living cells. Analysis of HIV-1-infected cells revealed that, upon assembly, HIV-1 is able to specifically trap PI(4,5)P2 and cholesterol, but not phosphatidylethanolamine or sphingomyelin. Furthermore, our data showed that Gag is the main driving force to restrict the mobility of PI(4,5)P2 and cholesterol at the cell plasma membrane. This is the first direct evidence highlighting that HIV-1 creates its own specific lipid environment by selectively recruiting PI(4,5)P2 and cholesterol as a membrane nanoplatform for virus assembly.

Communication between the transverse cervical nerve (C2,3) and marginal mandibular branch of the facial nerve: a cadaveric and clinical study

Several branches of the facial nerve are known to anastomose with branches of the cervical plexus, other cranial nerves, and the trigeminal nerve. Communication between the sensory transverse cervical nerve (C2, 3) and marginal mandibular nerve is, however, less well known, and in a previous study of 86 neck dissections we reported a 2.3% incidence of anastomoses between them. In this prospective study, we meticulously searched for more examples using both formalin-fixed cadavers and neck dissections. A total of 102 necks were included (both sides of 36 cadavers (n=72 necks), and 30 patients who had neck dissection for the management of squamous cell carcinoma). We found communications between these nerves on one side of a cadaver and in one neck dissection. When combined with the numbers from our previous study, the overall incidence was 2.1% in 188 necks. The marginal mandibular nerve was inseparable from the anastomosis with the transverse cervical nerve, and the variant should not be forgotten if we are to reduce the chance of postoperative weakness of the lower lip, particularly when operative exposure is more limited (such as during removal of the submandibular gland).

Men's use of sexual health and HIV services in Swaziland: a mixed methods study

BACKGROUND

Over one-quarter of the adult population in Swaziland is estimated to be HIV positive. Men's use of sexual health (SH) services has significant implications for HIV prevention. This study aimed to understand Swazi men's health-seeking behaviours in relation to SH and HIV services.

METHODS

A household survey was conducted in Manzini (n=503), complemented by 23 semi-structured interviews and two focus group discussions (with a total of 10 participants).

RESULTS

One-third of male survey participants used SH services in the past year, most commonly HIV testing (28%). Service users were more likely to be sexually active (aOR 3.21, 95% CI: 1.81-5.68 for those with one partner; and aOR 2.35, 95% CI: 1.25-4.41 for those with multiple partners) compared with service non-users. Service users were less likely to prefer HIV services to be separated from other healthcare services (aOR 0.50, 95% CI: 0.35-0.71), or to agree with travelling further for their HIV test (aOR 0.52, 95% CI: 0.33-0.82) compared with non-users, after controlling for age-group and education. Men avoided SH services because they feared being stigmatised by STI/HIV testing, are uncomfortable disclosing SH problems to female healthcare providers, and avoided HIV testing by relying on their wife's results as a proxy for their own status. Informal providers, such as traditional healers, were often preferred because practitioners were more often male, physical exams were not required and appointments and payment options were flexible.

CONCLUSION

To improve men's uptake of SH services, providers and services need to be more sensitive to men's privacy concerns, time restrictions and the potential stigma associated with STI/HIV testing.

What is the prevalence of and associations with forced labour experiences among male migrants from Dolakha, Nepal? Findings from a cross-sectional study of returnee migrants

OBJECTIVES

Growing numbers of people are migrating outside their country for work, and many experience precarious conditions, which have been linked to poor physical and mental health. While international dialogue on human trafficking, forced labour and slavery increases, prevalence data of such experiences remain limited.

METHODS

Men from Dolakha, Nepal, who had ever migrated outside of Nepal for work were interviewed on their experiences, from predeparture to return (n=194). Forced labour was assessed among those who returned within the past 10 years (n=140) using the International Labour Organization's forced labour dimensions: (1) unfree recruitment; (2) work and life under duress; and (3) impossibility to leave employer. Forced labour is positive if any one of the dimensions is positive.

RESULTS

Participants had worked in India (34%), Malaysia (34%) and the Gulf Cooperation Council countries (29%), working in factories (29%), as labourers/porters (15%) or in skilled employment (12%). Among more recent returnees (n=140), 44% experienced unfree recruitment, 71% work and life under duress and 14% impossibility to leave employer. Overall, 73% experienced forced labour during their most recent labour migration.Forced labour was more prevalent among those who had taken loans for their migration (PR 1.23) and slightly less prevalent among those who had migrated more than once (PR 0.87); however the proportion of those who experienced forced labour was still high (67%). Age, destination and duration of stay were associated with only certain dimensions of forced labour.

CONCLUSION

Forced labour experiences were common during recruitment and at destination. Migrant workers need better advice on assessing agencies and brokers, and on accessing services at destinations. As labour migration from Nepal is not likely to reduce in the near future, interventions and policies at both source and destinations need to better address the challenges migrants face so they can achieve safer outcomes.

Intra-articular injection of synovial mesenchymal stem cells improves cartilage repair in a mouse injury model

Controversy remains whether articular cartilage has an endogenous stem/progenitor cell population, since its poor healing capacity after injury can lead to diseases such as osteoarthritis. In the joint environment there are mesenchymal stem/progenitor cells (MSCs) in the synovial membrane and synovial fluid that can differentiate into cartilage, but it is still under debate if these cells contribute to cartilage repair in vivo. In this study, we isolated a Sca-1 positive, chondrogenesis capable population of mouse synovial MSCs from C57BL6 and MRL/MpJ “super-healer” strains. Intra-articular injection of Sca-1 + GFP + synovial cells from C57BL6 or MRL/MpJ into C57BL6 mice following cartilage injury led to increased cartilage repair by 4 weeks after injury. GFP expression was detected in the injury site at 2 weeks, but not 4 weeks after injury. These results suggest that synovial stem/progenitor cells, regardless of strain background, have beneficial effects when injected into an injured joint. MSCs derived from MRL/MpJ mice did not promote an increased repair capacity compared to MSCs derived from non-healing C57BL6 controls; however, MRL/MpJ MSCs were observed within the defect area at the time points examined, while C57BL6 MSCs were not.

Atmospheric benzenoid emissions from plants rival those from fossil fuels

Despite the known biochemical production of a range of aromatic compounds by plants and the presence of benzenoids in floral scents, the emissions of only a few benzenoid compounds have been reported from the biosphere to the atmosphere. Here, using evidence from measurements at aircraft, ecosystem, tree, branch and leaf scales, with complementary isotopic labeling experiments, we show that vegetation (leaves, flowers, and phytoplankton) emits a wide variety of benzenoid compounds to the atmosphere at substantial rates. Controlled environment experiments show that plants are able to alter their metabolism to produce and release many benzenoids under stress conditions. The functions of these compounds remain unclear but may be related to chemical communication and protection against stress. We estimate the total global secondary organic aerosol potential from biogenic benzenoids to be similar to that from anthropogenic benzenoids (~10 Tg y⁻¹), pointing to the importance of these natural emissions in atmospheric physics and chemistry.

Evaluating endogenous repair of focal cartilage defects in C57BL/6 and MRL/MpJ mice using 9.4T magnetic resonance imaging: A pilot study

The use of magnetic resonance imaging (MRI) for evaluating joint injuries is often considered superior to radiography due to the capacity of MRI for visualizing both soft and hard tissues. While longitudinal studies regarding cartilage repair have been undertaken on patients and in larger animal models, a method has yet to be developed for mouse cartilage to be repeatedly and non-invasively evaluated over time. The aim of this pilot study was to investigate if morphological changes following a focal cartilage injury in mice could be measured by 9.4T magnetic resonance imaging. Focal cartilage defects were induced in the left knee of 4-6weeks old C57BL/6 and MRL/MpJ mice. At endpoints 0, 2, and 4weeks post-injury, legs were dissected out and imaged ex vivo. The defect could be detected by MRI immediately after injury, appearing as a hyperintense focal point and with size similar to that of the surgical tool used. Defects were visible in both strains up to 4weeks post-injury, although signal intensity decreased over time. One C57BL/6 in particular, displayed extensive fibrosis in the patellar tendon at 4weeks as assessed by histology, while the MR images of the same animal displayed a clear, structural distinction between the patella and the new tissue growth. Overall, our results suggest that MRI could be used for longitudinal studies in murine cartilage injury models to evaluate certain characteristics of repair not detectable through histology.

Intimate partner violence victimization and alcohol consumption in women: a systematic review and meta-analysis

AIMS

To examine the evidence of association between intimate partner physical or sexual violence (IPV) victimization and alcohol consumption in women.

METHODS

We conducted a systematic review and meta-analysis of cross-sectional and longitudinal studies released before 6 June 2013. Studies providing an estimate of association between violence and alcohol consumption or alcohol use disorders were eligible for inclusion. Quality was assessed and random effects meta-analyses used to generate pooled odds ratios (OR) where appropriate. Higgins I(2) where P<0.10 was taken to indicate heterogeneity.

RESULTS

Fifty-five studies providing 102 estimates of association met the inclusion criteria. Most estimates were not controlled for partner alcohol use and other key confounders. Seven longitudinal studies provided 12 estimates of the association between alcohol and subsequent IPV; nine of 12 estimates showed a direction of increased odds of subsequent IPV, pooled OR=1.27 [95% confidence interval (CI)=1.07-1.52], I(2) =0%, P=0.437. Nine longitudinal studies provided 15 estimates of association between IPV and subsequent alcohol use; 14 of 15 estimates showed a direction of increased odds of subsequent alcohol use, pooled OR=1.25 (95% CI 1.02-1.52), I(2)=0%, P=0.751. Cross-sectional studies showed an association between IPV and alcohol use, pooled OR=1.80, 95% CI 1.58-2.06, but with substantial heterogeneity, I(2)=60.8%, P<0.0001. Definition of alcohol use partly accounted for heterogeneity in cross-sectional estimates.

CONCLUSIONS

There is a clear positive association between alcohol use and intimate partner physical or sexual violence victimization among women, suggesting a need for programming and research that addresses this link. However, the temporal direction of the association remains unclear. Longitudinal studies with multiple waves of data collection are needed.

A comparative risk assessment of burden of disease and injury attributable to 67 risk factors and risk factor clusters in 21 regions, 1990-2010: a systematic analysis for the Global Burden of Disease Study 2010

BACKGROUND

Quantification of the disease burden caused by different risks informs prevention by providing an account of health loss different to that provided by a disease-by-disease analysis. No complete revision of global disease burden caused by risk factors has been done since a comparative risk assessment in 2000, and no previous analysis has assessed changes in burden attributable to risk factors over time.

METHODS

We estimated deaths and disability-adjusted life years (DALYs; sum of years lived with disability [YLD] and years of life lost [YLL]) attributable to the independent effects of 67 risk factors and clusters of risk factors for 21 regions in 1990 and 2010. We estimated exposure distributions for each year, region, sex, and age group, and relative risks per unit of exposure by systematically reviewing and synthesising published and unpublished data. We used these estimates, together with estimates of cause-specific deaths and DALYs from the Global Burden of Disease Study 2010, to calculate the burden attributable to each risk factor exposure compared with the theoretical-minimum-risk exposure. We incorporated uncertainty in disease burden, relative risks, and exposures into our estimates of attributable burden.

FINDINGS

In 2010, the three leading risk factors for global disease burden were high blood pressure (7·0% [95% uncertainty interval 6·2-7·7] of global DALYs), tobacco smoking including second-hand smoke (6·3% [5·5-7·0]), and alcohol use (5·5% [5·0-5·9]). In 1990, the leading risks were childhood underweight (7·9% [6·8-9·4]), household air pollution from solid fuels (HAP; 7·0% [5·6-8·3]), and tobacco smoking including second-hand smoke (6·1% [5·4-6·8]). Dietary risk factors and physical inactivity collectively accounted for 10·0% (95% UI 9·2-10·8) of global DALYs in 2010, with the most prominent dietary risks being diets low in fruits and those high in sodium. Several risks that primarily affect childhood communicable diseases, including unimproved water and sanitation and childhood micronutrient deficiencies, fell in rank between 1990 and 2010, with unimproved water and sanitation accounting for 0·9% (0·4-1·6) of global DALYs in 2010. However, in most of sub-Saharan Africa childhood underweight, HAP, and non-exclusive and discontinued breastfeeding were the leading risks in 2010, while HAP was the leading risk in south Asia. The leading risk factor in Eastern Europe, most of Latin America, and southern sub-Saharan Africa in 2010 was alcohol use; in most of Asia, North Africa and Middle East, and central Europe it was high blood pressure. Despite declines, tobacco smoking including second-hand smoke remained the leading risk in high-income north America and western Europe. High body-mass index has increased globally and it is the leading risk in Australasia and southern Latin America, and also ranks high in other high-income regions, North Africa and Middle East, and Oceania.

INTERPRETATION

Worldwide, the contribution of different risk factors to disease burden has changed substantially, with a shift away from risks for communicable diseases in children towards those for non-communicable diseases in adults. These changes are related to the ageing population, decreased mortality among children younger than 5 years, changes in cause-of-death composition, and changes in risk factor exposures. New evidence has led to changes in the magnitude of key risks including unimproved water and sanitation, vitamin A and zinc deficiencies, and ambient particulate matter pollution. The extent to which the epidemiological shift has occurred and what the leading risks currently are varies greatly across regions. In much of sub-Saharan Africa, the leading risks are still those associated with poverty and those that affect children.

FUNDING

Bill & Melinda Gates Foundation.

Impact of income and education on drug purchasing decisions in Hong Kong Chinese cancer patients: a pilot study

BACKGROUND

The affordability of diagnostic, preventive and therapeutic interventions is a global concern, particularly in the developing world. To clarify the educational and financial factors that influence purchasing decisions, we conducted a survey of Hong Kong cancer patients across a broad social spectrum.

METHODS

A questionnaire was designed to assess the effect of costs on purchasing decisions relating to six drug-related variables: efficacy, tolerability, convenience, safety, peer pressure, and uncertainty. Validation of the original 31-part survey resulted in a final set of 22 core questions that was administered to 51 consecutive oncology patients who were characterized in terms of varying household income and educational level.

RESULTS

Most respondents (87.6%) were Hong Kong-born or mainland Chinese. There was a strong correlation between household income and education. Demand for drug tolerability and safety was high and cost-inelastic across all educational and income groups. An unexpected finding was that patients from low-income/education households were keen to purchase costly medications (whether Western, or Chinese herbs) of reputed high efficacy, whereas patients from middle-income/-education backgrounds were more negatively influenced by considerations of cost. Only the most affluent and well-educated patients valued overall survival above disease-free survival when making drug purchasing decisions; this cohort was also the least influenced by peer pressure, and the most willing to pay extra for drugs offering more convenience alone.

CONCLUSION

Low-income/education Asian patients had paradoxically high expectations of costly drug interventions. Although larger studies addressing this issue are needed to confirm these conclusions, public education initiatives aimed at protecting low-income/education patients from exploitation or disappointment may be desirable.

Reducing chimera formation during PCR amplification to ensure accurate genotyping

Measurements of population diversity are fundamental to the reconstruction of the evolutionary and epidemiological history of organisms. Commonly used protocols to measure population diversity using the polymerase chain reaction (PCR) are prone to the introduction of artificial chimeras. These are often difficult to detect and can confound the correct interpretation of results due to the false generation of recombinants when the underlying DNA sample contains multiple distinct templates. This study presents a standardised procedure to suppress the formation of artificial chimeras during PCR amplification. The solution is based on the accurate determination of the efficiency and end point of the log-linear phase of a PCR. This procedure will facilitate the generation of data sets that more accurately reflect the underlying population diversity rather than artifacts introduced by the process itself.

How much cost can one patient bear? The influence of income and education on drug purchasing decisions in Hong Kong Chinese cancer patients

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Background: Inflation of anticancer drug prices is a growing problem worldwide. This problem is especially challenging in Asia, where rising healthcare expectations clash with low incomes and weak insurance. To clarify the factors influencing drug purchasing decisions in this context, we conducted a survey of Hong Kong oncology patients. Methods: A questionnaire was designed to assess the effect of cost on purchasing decisions relating to drug variables such as (1) efficacy, (2) tolerability, (3) convenience, (4) safety, (5) novelty and (6) reliability. Validation of the original 33-part survey resulted in a final set of 21 questions that was administered to 51 oncology patients. These respondents were characterised in terms of age, household income, insurance, educational level, family circumstances, occupation, ethnicity, religious beliefs, prognosis, and co-morbidity. Results: Most respondents were Hong Kong (68.8%), mainland Chinese (18.8%) or Caucasian (10.4%). There was a strong correlation between household income and education. Patients from middle-income (US$7,000–14,000 per month) households were most influenced in their decisions by costs and insurance rebates, whereas those from low-income households (less than US$3,000 per month) were keenest to purchase expensive medications, whether Western or traditional Chinese remedies. Demand for drug safety was cost-inelastic across all income groups, independent of gains in efficacy. Even when free treatment was offered, therapeutic uncertainties (e.g., early-phase drugs or randomization) proved unpopular with all income groups. Only the most affluent and well-educated patients valued overall survival above disease-free survival in making decisions, suggesting that less educated cohorts did not understand these concepts. Conclusion: These data suggest that low-income cancer patients and their families may have unrealistic expectations of high-priced medications, based either on misunderstanding or cultural pressures. Greater educational efforts targeting this large population sector may be needed to avoid worsening dissatisfaction and social unrest in the future.

No significant financial relationships to disclose.

Inhaled fluticasone in bronchiectasis: a 12 month study

BACKGROUND

The clinical efficacy of inhaled corticosteroid (ICS) treatment has not been evaluated in bronchiectasis, despite the presence of chronic airway inflammation.

METHODS

After three consecutive weekly visits, 86 patients were randomised to receive either fluticasone 500 mug twice daily (n = 43, 23F, mean (SD) age 57.7 (14.4) years) or matched placebo (n = 43, 34F, 59.2 (14.2) years) and reviewed regularly for 52 weeks in a double blind fashion.

RESULTS

35 and 38 patients in the fluticasone and placebo groups completed the study. Significantly more patients on ICS than on placebo showed improvement in 24 hour sputum volume (OR 2.5, 95% CI 1.1 to 6.0, p = 0.03) but not in exacerbation frequency, forced expiratory volume in 1 second, forced vital capacity, or sputum purulence score. Significantly more patients with Pseudomonas aeruginosa infection receiving fluticasone showed improvement in 24 hour sputum volume (OR 13.5, 95% CI 1.8 to 100.2, p = 0.03) and exacerbation frequency (OR 13.3, 95% CI 1.8 to 100.2, p = 0.01) than those given placebo. Logistic regression models revealed a significantly better response in sputum volume with fluticasone treatment than with placebo among subgroups of patients with 24 hour sputum volume <30 ml (p = 0.04), exacerbation frequency </=2/year (p = 0.04), and sputum purulence score >5 (p = 0.03).

CONCLUSIONS

ICS treatment is beneficial to patients with bronchiectasis, particularly those with P. aerurginosa infection.

The dimer initiation sequence stem-loop of human immunodeficiency virus type 1 is dispensable for viral replication in peripheral blood mononuclear cells

Human immunodeficiency virus type 1 (HIV-1) contains two copies of genomic RNA that are noncovalently linked via a palindrome sequence within the dimer initiation site (DIS) stem-loop. In contrast to the current paradigm that the DIS stem or stem-loop is critical for HIV-1 infectivity, which arose from studies using T-cell lines, we demonstrate here that HIV-1 mutants with deletions in the DIS stem-loop are replication competent in peripheral blood mononuclear cells (PBMCs). The DIS mutants contained either the wild-type (5'GCGCGC3') or an arbitrary (5'ACGCGT3') palindrome sequence in place of the 39-nucleotide DIS stem-loop (NL(CGCGCG) and NL(ACGCGT)). These DIS mutants were replication defective in SupT1 cells, concurring with the current model in which DIS mutants are replication defective in T-cell lines. All of the HIV-1 DIS mutants were replication competent in PBMCs over a 40-day infection period and had retained their respective DIS mutations at 40 days postinfection. Although the stability of the virion RNA dimer was not affected by our DIS mutations, the RNA dimers exhibited a diffuse migration profile when compared to the wild type. No defect in protein processing of the Gag and GagProPol precursor proteins was found in the DIS mutants. Our data provide direct evidence that the DIS stem-loop is dispensable for viral replication in PBMCs and that the requirement of the DIS stem-loop in HIV-1 replication is cell type dependent.

Pseudomonas aeruginosa adherence to human basement membrane collagen in vitro

The mechanisms for Pseudomonas aeruginosa colonisation in the airways of patients with bronchiectasis and cystic fibrosis are poorly understood. P. aeruginosa could evade mucociliary clearance by adhering to the basement membrane at areas denuded of intact respiratory epithelium. The authors have developed an in vitro model to study P. aeruginosa adherence to human basement membrane type-IV collagen by using scanning electron microscopy. P. aeruginosa adherence density was determined as the number of P. aeruginosa per 20 microscope fields (2,000x) to log inocular size after incubation at 37 degrees C for 45 min. The presence of phytohaemagglutinin (PHA)-E, which binds specifically to D-galactose-beta1-4-D-N-acetylglucosamine, significantly reduced P. aeruginosa adherence density compared with control. The presence of heparin and calcium also significantly reduced P. aeruginosa adherence density. P. aeruginosa adherence was not affected by the presence of proline, trans-hydroxyproline, glycine, galactose, N-acetylneuraminic acid, N-acetylglucosamine or Arachis hypogea. Pseudomonas aeruginosa adherence probably acts via recognition of the D-galactose-beta1-4-D-N-acetylglucosamine sequence on type-IV collagen and this process could be inhibited by heparin and calcium. As persistent Pseudomonas aeruginosa colonisation is detrimental to patients with cystic fibrosis and bronchiectasis and there is currently no effective treatment for its eradication, these results could lead to novel therapy for persistent Pseudomonas aeruginosa infection.

Overexpression and incorporation of GagPol precursor does not impede packaging of HIV-1 tRNA(Lys3) but promotes intracellular budding of virus-like particles

We have recently demonstrated that alteration of the human immunodeficiency virus type 1 (HIV-1) Gag/GagPol ratio in virus-producing cells reduces the infectivity of progeny viruses and hinders the formation of stable virion RNA dimers without impairing virion packaging of the viral genomic RNA. In addition, we have previously shown that the expression of GagPol mediates the selective packaging of tRNA(Lys3). In this study we report that overexpression of uncleaved GagPol in the virus-producing cell did not alter the packaging levels of tRNA(Lys3). Similarly, altering the virion-associated Gag/GagPol ratio did not affect the virion packaging of the HIV-1 envelope protein nor cyclophilin A. Thin section electron microscopy analysis of the cells overexpressing protease-defective [PR(-)] GagPol revealed immature virions but no mature virions. These immature virions were seen both extracellularly and in membrane-bound cytoplasmic vacuoles. Furthermore, an accumulation of electron-dense material was occasionally found at the plasma membrane and associated with intracytoplasmic membranous vacuoles in cells expressing excess PR(-) GagPol. No intracellular HIV was seen in the wild-type control. Density gradient analysis showed that the overall density of these mutant virions with excess PR(-) GagPol was identical to that of the wild-type HIV-1. The findings indicate that overexpression of PR(-) GagPol, in the presence of Gag synthesis, promotes intracellular budding of the mutant virions and inhibits virus maturation.

The conformation of the mature dimeric human immunodeficiency virus type 1 RNA genome requires packaging of pol protein

The packaging of a mature dimeric RNA genome is an essential step in human immunodeficiency virus type 1 (HIV-1) replication. We have previously shown that overexpression of a protease (PR)-inactive HIV-1 Gag-Pro-Pol precursor protein generates noninfectious virions that contain mainly monomeric RNA (M. Shehu-Xhilaga, S. M. Crowe, and J. Mak, J. Virol. 75:1834-1841, 2001). To further define the contribution of HIV-1 Gag and Gag-Pro-Pol to RNA maturation, we analyzed virion RNA dimers derived from Gag particles in the absence of Gag-Pro-Pol. Compared to wild-type (WT) dimeric RNAs, these RNA dimers have altered mobility and low stability under electrophoresis conditions, suggesting that the HIV-1 Gag precursor protein alone is not sufficient to stabilize the dimeric virion RNA structure. The inclusion of an active viral PR, without reverse transcriptase (RT) and integrase (IN), rescued the stability of the virion RNA dimers in the Gag particles but did not restore the mobility of the RNAs, suggesting that RT and IN are also required for virion RNA dimer maturation. Thin-section electron microscopy showed that viral particles deficient in RT and IN contain empty cone-shaped cores. The abnormal core structure indicates a requirement for Gag-Pro-Pol packaging during core maturation. Supplementing viral particles with either RT or IN via Vpr-RT or Vpr-IN alone did not correct the conformation of the dimer RNAs, whereas expression of both RT and IN in trans as a Vpr-RT-IN fusion restored RNA dimer conformation to that of the WT virus and also restored the electron-dense, cone-shaped virion core characteristic of WT virus. Our data suggest a role for RT-IN in RNA dimer conformation and the formation of the electron-dense viral core.

Sudden permanent hearing loss following anterior inferior cerebellar artery infarction

Anterior inferior cerebellar artery infarction with the only sequel being a permanent unilateral hearing loss is described. The damage was confirmed by magnetic resonance imaging. Hearing loss of vascular cause may be more common and permanent than realised, and missed if the other neurological deficits have resolved.

Proteolytic processing of the p2/nucleocapsid cleavage site is critical for human immunodeficiency virus type 1 RNA dimer maturation

Differences in virion RNA dimer stability between mature and protease-defective (immature) forms of human immunodeficiency virus type 1 (HIV-1) suggest that maturation of the viral RNA dimer is regulated by the proteolytic processing of the HIV-1 Gag and Gag-Pol precursor proteins. However, the proteolytic processing of these proteins occurs in several steps denoted primary, secondary, and tertiary cleavage events and, to date, the processing step associated with formation of stable HIV-1 RNA dimers has not been identified. We show here that a mutation in the primary cleavage site (p2/nucleocapsid [NC]) hinders formation of stable virion RNA dimers, while dimer stability is unaffected by mutations in the secondary (matrix/capsid [CA], p1/p6) or a tertiary cleavage site (CA/p2). By introducing mutations in a shared cleavage site of either Gag or Gag-Pol, we also show that the cleavage of the p2/NC site in Gag is more important for dimer formation and stability than p2/NC cleavage in Gag-Pol. Electron microscopy analysis of viral particles shows that mutations in the primary cleavage site in Gag but not in Gag-Pol inhibit viral particle maturation. We conclude that virion RNA dimer maturation is dependent on proteolytic processing of the primary cleavage site and is associated with virion core formation.

Lipid rafts and HIV-1: from viral entry to assembly of progeny virions

BACKGROUND

Lipid rafts are currently an intensely investigated topic of cell biology. In addition to a demonstrated role in signal transduction of the host cell, lipid rafts serve as entry and exit sites for microbial pathogens and toxins, such as FimH-expressing enterobacteria, influenza virus, measles virus and cholera toxin. Furthermore, caveolae, a specialised form of lipid raft, are required for the conversion of the non-pathogenic prion protein to the pathogenic scrapie isoform.

OBJECTIVES

A number of reports have shown, directly or indirectly, that lipid rafts are important at various stages of the human immunodeficiency virus type-1 (HIV-1) replication cycle. The purpose of this paper is to provide a brief overview of the role of membrane-associated lipid rafts in cell biology, and to evaluate how HIV-1 has hijacked this cellular component to support HIV-1 replication. Special sections are devoted to discussing the role of lipid rafts in (1) the entry of HIV-1, (2) signal transduction regulation in HIV-1-infected cells, (3) the trafficking of HIV-1 proteins via lipid rafts during HIV-1 assembly; and a further section discusses the role of cholesterol in mature HIV-1.

SUMMARY

Like a number of other pathogens, HIV-1 has evolved to rely on the host cell lipid rafts to support its propagation during multiple stages of the HIV-1 replication cycle. This review has highlighted the importance of lipid rafts in HIV-1 replication.

Gag-Pol supplied in trans is efficiently packaged and supports viral function in human immunodeficiency virus type 1

The intracellular trafficking and subsequent incorporation of Gag-Pol into human immunodeficiency virus type 1 (HIV-1) remains poorly defined. Gag-Pol is encoded by the same mRNA as Gag and is generated by ribosomal frameshifting. The multimerization of Gag and Gag-Pol is an essential step in the formation of infectious viral particles. In this study, we examined whether the interaction between Gag and Gag-Pol is initiated during protein translation in order to facilitate the trafficking and subsequent packaging of Gag-Pol into the virion. A conditional cotransfection system was developed in which virion formation required the coexpression of two HIV-1-based plasmids, one that produces both Gag and Gag-Pol and one that only produces Gag-Pol. The Gag-Pol proteins were either immunotagged with a His epitope or functionally tagged with a mutation (K65R) in reverse transcriptase that is associated with drug resistance. Gag-Pol packaging was assessed to determine whether the Gag-Pol incorporated into the virion was preferentially packaged from the plasmid that expressed both Gag and Gag-Pol or whether it could be packaged from either plasmid. Our data show that translation of Gag and Gag-Pol from the same mRNA is not critical for virion packaging of the Gag-Pol polyprotein or for viral function.

nef-deleted HIV-1 inhibits phagocytosis by monocyte-derived macrophages in vitro but not by peripheral blood monocytes in vivo

OBJECTIVE

HIV-1 infection impairs a number of macrophage effector functions, but the mechanism is unknown. We studied the role of HIV-1 Nef in modulating phagocytosis by human monocytes and monocyte-derived macrophages (MDM).

DESIGN AND METHODS

Using a flow cytometric assay, phagocytosis of Mycobacterium avium complex (MAC) by monocytes in whole blood of Sydney Blood Bank Cohort (SBBC) members infected with a nef-deleted (Delta nef) strain of HIV-1 was compared with that of monocytes from uninfected or wild-type (WT) HIV-infected subjects. The specific impact of Nef on phagocytosis by MDM was determined by either infecting cells in vitro with Delta nef strains of HIV-1 or electroporating Nef into uninfected MDM.

RESULTS

MAC phagocytic capacity of monocytes from SBBC members was equivalent to that of cells from uninfected individuals (P = 0.81); it was greater than that of cells from individuals infected with WT HIV-1 (P < 0.0001), irrespective of CD4 counts and HIV viral load. In contrast, in vitro infection of MDM with either Delta nef or WT strains of HIV-1 resulted in similar levels of HIV replication and equivalent impairment of phagocytosis via Fc gamma and complement receptors. Electroporation of Nef into MDM did not alter phagocytic capacity.

CONCLUSIONS

This study provides evidence demonstrating the complex indirect effect of Nef on phagocytosis by peripheral blood monocytes (infrequently infected with HIV-1) in vivo. Conversely, the fact that MDM infected with either Delta nef or WT HIV-1 in vitro (high multiplicity of infection) show comparably impaired phagocytosis, indicates that HIV-1 infection of macrophages can directly impair function, independent of Nef.

Telomere length in leukocyte subpopulations of patients with aplastic anemia

In most human cells, the average length of telomere repeats at the ends of chromosomes provides indirect information about their mitotic history. To study the turnover of stem cells in patients with bone marrow failure syndromes, the telomere length in peripheral blood granulocytes and lymphocytes from patients with aplastic anemia (AA, n = 56) and hemolytic paroxysmal nocturnal hemoglobinuria (n = 6) was analyzed relative to age-matched controls by means of fluorescence in situ hybridization and flow cytometry. The telomere lengths in granulocytes from patients with AA were found to be significantly shorter than those in age-adjusted controls (P =.001). However, surprisingly, telomere length in granulocytes from AA patients who had recovered after immunosuppressive therapy did not differ significantly from controls, whereas untreated patients and nonresponders with persistent severe pancytopenia showed marked and significant telomere shortening. These results support extensive proliferation of hematopoietic stem cells in subgroups of AA patients. Because normal individuals show significant variation in telomere length, individual measurements in blood cells from AA patients may be of limited value. Whether sequential telomere length measurements can be used as a prognostic tool in this group of disorders remains to be clarified. (Blood. 2001;97:895-900)

Maintenance of the Gag/Gag-Pol ratio is important for human immunodeficiency virus type 1 RNA dimerization and viral infectivity

Production of the human immunodeficiency virus type 1 (HIV-1) Gag-Pol precursor protein results from a -1 ribosomal frameshifting event. In infected cells, this generates Gag and Gag-Pol in a ratio that is estimated to be 20:1, a ratio that is conserved among retroviruses. To examine the impact of this ratio on HIV-1 replication and viral assembly, we altered the Gag/Gag-Pol ratio in virus-producing cells by cotransfecting HIV-1 proviral DNA with an HIV-1 Gag-Pol expression vector. Two versions of the Gag-Pol expression vector were used; one contains an active protease [PR(+)], and the other contains an inactive protease [PR(-)]. In an attempt to produce viral particles with Gag/Gag-Pol ratios ranging from 20:21 to 20:1 (wild type), 293T cells were cotransfected with various ratios of wild-type proviral DNA and proviral DNA from either Gag-Pol expression vector. Viral particles derived from cells with altered Gag/Gag-Pol ratios via overexpression of PR(-) Gag-Pol showed a ratio-dependent defect in their virion protein profiles. However, the defects in virion infectivity were independent of the nature of the Gag-Pol expression vector, i.e., PR(+) or PR(-). Based on equivalent input of reverse transcriptase activity, we estimated that HIV-1 infectivity was reduced 250- to 1,000-fold when the Gag/Gag-Pol ratio in the virion-producing cells was altered from 20:1 to 20:21. Although virion RNA packaging was not affected by altering Gag/Gag-Pol ratios, changing the ratio from 20:1 to 20:21 progressively reduced virion RNA dimer stability. The impact of the Gag/Gag-Pol ratio on virion RNA dimerization was amplified when the Gag-Pol PR(-) expression vector was expressed in virion-producing cells. Virions produced from cells expressing Gag and Gag-Pol PR(-) in a 20:21 ratio contained mainly monomeric RNA. Our observations provide the first direct evidence that, in addition to proteolytic processing, the ratio of Gag/Gag-Pol proteins is also important for RNA dimerization and that stable RNA dimers are not required for encapsidation of genomic RNA in HIV-1.

Na(+)-K(+)-ATPase-mediated basolateral rubidium uptake in the maturing rabbit cortical collecting duct

Within the renal cortical collecting duct (CCD), transepithelial Na(+) absorption and K(+) secretion are linked to basolateral Na(+)-K(+)-ATPase activity. Our purpose was to examine the developmental changes in basolateral Na(+)-K(+)-ATPase-mediated (86)rubidium (Rb) uptake, its inhibitor sensitivity and relationship to pump hydrolytic activity and Na(+) transport. Multiple CCDs ( approximately 6 mm) from maturing rabbits were affixed to coverslips, preincubated at 37 degrees C for 10 min (+/-1-2.5 mM ouabain or 10 or 100 micro M Schering-28080, an inhibitor of H(+)-K(+)-ATPase), and then transferred to prewarmed incubation solution containing tracer amounts of (86)Rb (+/-inhibitors). After 1 min at 37 degrees C, tubular samples were rinsed and permeabilized and isotope counts were measured to calculate basolateral Rb uptake. Ouabain-inhibitable Rb uptake, an index of basolateral Na(+)-K(+) pump activity, increased approximately 3-fold during the 1st 8 wk of postnatal life (P < 0.03). The approximately 2-fold increase in absolute rate of Rb uptake between 1 and 6 wk (2.64 +/- 0.45 to 5.02 +/- 0.32 pmol. min(-1). mm(-1)) did not reach statistical significance. The rate of basolateral Rb uptake increased further after the 6th wk of life to 7.29 +/- 0.53 pmol. min(-1). mm(-1) in adult animals (P < 0.03 vs. 6 wk). Schering-28080 failed to inhibit Rb uptake, implying that functional H(+)-K(+)-ATPase is absent at the basolateral membrane. Na(+)-K(+)-ATPase hydrolytic activity, determined by using a microassay that measured inorganic phosphate release from [gamma-(32)P]ATP under maximum velocity (V(max)) conditions, also increased in the differentiating CCD (from 316.2 +/- 44.4 pmol. h(-1). mm(-1) at 2 wk to 555.9 +/- 105.1 at 4 wk to 789.7 +/- 145.0 at 6 wk; r = 1.0 by linear regression analysis; P < 0.005). The parallel approximately 2.5-fold increases in Na(+)-K(+)-ATPase activity and ouabain-sensitive Rb uptake between 2- and 6-wk postnatal age suggest that the developmental increase in basolateral transport capacity is due predominantly to an increase in enzyme abundance. The signals mediating the developmental increase in Na(+)-K(+)-ATPase activity in the CCD remain to be defined.

The practice of evidence-based medicine in an acute medical ward: retrospective study

OBJECTIVE

To review the practice of evidence-based medicine with respect to drug treatment given to medical in-patients.

DESIGN

Retrospective study.

SETTING

Teaching hospital, Hong Kong.

PATIENTS

Medical records of 129 consecutive patients who were admitted to the acute adult general medical ward from 1 September 1998 to 30 September 1998 were reviewed.

MAIN OUTCOME MEASURES

Primary diagnoses, drug treatments prescribed, and the level of evidence (based on a literature search of randomised controlled trials and relevant studies) that supported the treatment given.

RESULTS

For the 129 patients studied, 91 drug interventions had been prescribed on 312 occasions. Treatment that was supported by randomised controlled trials was prescribed in 162 (52.9%) cases. In 121 (38.8%) cases, patients were given standard and commonly used drugs that were not supported by evidence from clinical trials, and in 29 (9.3%) cases, the treatments given had no substantial supporting evidence. The management of some frequently encountered medical conditions was not based on trial data, because the relevant studies had not been conducted.

CONCLUSION

Basing treatment on comparative efficacy results is a worthwhile goal, but there are limitations in conducting literature searches to identify relevant trials and studies. Evidence-based medical practice is not applicable in a large number of commonly encountered conditions.

Granulocyte-macrophage colony-stimulating factor inhibits HIV-1 replication in monocyte-derived macrophages

BACKGROUND

Previous studies of the effect of granulocyte-macrophage colony-stimulating factor (GM-CSF) on HIV-1 replication in macrophages have had inconsistent results, variously reporting no effect, augmentation or inhibition of viral replication.

OBJECTIVE

To investigate the regulation of HIV-1 in monocyte-derived macrophages (MDM) by GM-CSF in vitro.

METHODS

The role of GM-CSF on HIV-1 replication was assessed as supernatant and intracellular p24 antigen concentrations and by HIV-1 DNA and mRNA production under different culture conditions. Expression of CD4 and CCR5 receptors was examined. The effect of GM-CSF with an E21R mutation, which binds only to the alpha-chain of GM-CSF receptor, was used as an additional control.

RESULTS

GM-CSF consistently suppressed HIV-1 replication in human MDM in vitro, as assessed by supernatant and intracellular p24 antigen concentrations and HIV-1 gag mRNA expression. The inhibitory effect of GM-CSF on HIV-1 replication was observed regardless of HIV-1 strain, source of GM-CSF, stage of MDM maturation or timing of GM-CSF exposure in relation to HIV-1 infection. The effect was dose dependent and reversed by addition of a neutralizing monoclonal antibody (4D4). Flow cytometric analysis of surface expression of CD4 and CCR5 indicates that GM-CSF does not affect HIV-1 entry into MDM. Analysis of intracellular HIV-1 DNA and mRNA suggests that HIV-1 replication is inhibited at or before transcription. E21R GM-CSF had no effect on HIV-1 replication in MDM.

CONCLUSIONS

GM-CSF regulates HIV-1 replication in MDM, inhibiting HIV-1 replication through binding to the beta-chain of the GM-CSF receptor.

Extension of cell life-span and telomere length in animals cloned from senescent somatic cells

The potential of cloning depends in part on whether the procedure can reverse cellular aging and restore somatic cells to a phenotypically youthful state. Here, we report the birth of six healthy cloned calves derived from populations of senescent donor somatic cells. Nuclear transfer extended the replicative life-span of senescent cells (zero to four population doublings remaining) to greater than 90 population doublings. Early population doubling level complementary DNA-1 (EPC-1, an age-dependent gene) expression in cells from the cloned animals was 3.5- to 5-fold higher than that in cells from age-matched (5 to 10 months old) controls. Southern blot and flow cytometric analyses indicated that the telomeres were also extended beyond those of newborn (<2 weeks old) and age-matched control animals. The ability to regenerate animals and cells may have important implications for medicine and the study of mammalian aging.