Exposure to household air pollution from biomass-burning cookstoves and HbA1c and diabetic status among Honduran women.

Household air pollution from biomass cookstoves is estimated to be responsible for more than two and a half million premature deaths annually, primarily in low and middle-income countries where cardiometabolic disorders, such as Type II Diabetes, are increasing. Growing evidence supports a link between ambient air pollution and diabetes, but evidence for household air pollution is limited. This cross-sectional study of 142 women (72 with traditional stoves and 70 with cleaner-burning Justa stoves) in rural Honduras evaluated the association of exposure to household air pollution (stove type, 24-hour average kitchen and personal fine particulate matter [PM2.5 ] mass and black carbon) with glycated hemoglobin (HbA1c) levels and diabetic status based on HbA1c levels. The prevalence ratio (PR) per interquartile range increase in pollution concentration indicated higher prevalence of prediabetes/diabetes (vs normal HbA1c) for all pollutant measures (eg, PR per 84 µg/m3 increase in personal PM2.5 , 1.49; 95% confidence interval [CI], 1.11-2.01). Results for HbA1c as a continuous variable were generally in the hypothesized direction. These results provide some evidence linking household air pollution with the prevalence of prediabetes/diabetes, and, if confirmed, suggest that the global public health impact of household air pollution may be broader than currently estimated.

Birds as bioindicators of plastic pollution in terrestrial and freshwater environments: A 30-year review.

Plastic pollution is a global concern that has grown ever more acute in recent years. Most research has focused on the impact of plastic pollution in marine environments. However, plastic is increasingly being detected in terrestrial and freshwater environments with key inland sources including landfills, where it is accessible to a wide range of organisms. Birds are effective bioindicators of pollutants for many reasons, including their high mobility and high intra- and interspecific variation in trophic levels. Freshwater and terrestrial bird species are under-represented in plastic pollution research compared to marine species. We reviewed 106 studies (spanning from 1994 onwards) that have detected plastics in bird species dwelling in freshwater and/or terrestrial habitats, identifying knowledge gaps. Seventy-two studies focused solely on macroplastics (fragments >5 mm), compared to 22 microplastic (fragments <5 mm) studies. A further 12 studies identified plastics as both microplastics and macroplastics. No study investigated nanoplastic (particles <100 nm) exposure. Research to date has geographical and species' biases while ignoring nanoplastic sequestration in free-living freshwater, terrestrial and marine bird species. Building on the baseline search presented here, we urge researchers to develop and validate standardised field sampling techniques and laboratory analytical protocols such as Raman spectroscopy to allow for the quantification and identification of micro- and nanoplastics in terrestrial and freshwater environments and the species therein. Future studies should consistently report the internalised and background concentrations, types, sizes and forms of plastics. This will enable a better understanding of the sources of plastic pollution and their routes of exposure to birds of terrestrial and freshwater environments, providing a more comprehensive insight into the potential impacts on birds.

Impact of a cleaner-burning cookstove intervention on blood pressure in Nicaraguan women.

Few studies have evaluated the cardiovascular-related effects of indoor biomass burning or the role of characteristics such as age and obesity status, in this relationship. We examined the impact of a cleaner-burning cookstove intervention on blood pressure among Nicaraguan women using an open fire at baseline; we also evaluated heterogeneity of the impact by subgroups of the population. We evaluated changes in systolic and diastolic blood pressure from baseline to post-intervention (range: 273-383 days) among 74 female cooks. We measured indoor fine particulate matter (PM(2.5); N = 25), indoor carbon monoxide (CO; N = 32), and personal CO (N = 30) concentrations. Large mean reductions in pollutant concentrations were observed for all pollutants; for example, indoor PM(2.5) was reduced 77% following the intervention. However, pollution distributions (baseline and post-intervention) were wide and overlapping. Although substantial reductions in blood pressure were not observed among the entire population, a 5.9 mmHg reduction [95% confidence interval (CI): -11.3, -0.4] in systolic blood pressure was observed among women aged 40 or more years and a 4.6 mmHg reduction (95% CI: -10.0, 0.8) was observed among obese women. Results from this study provide an indication that certain subgroups may be more likely to experience improvements in blood pressure following a cookstove intervention.

HIV incidence among non-migrating persons following a household migration event: a population-based, longitudinal study in Uganda.

Background: The impact of migration on HIV risk among non-migrating household members is poorly understood. We measured HIV incidence among non-migrants living in households with and without migrants in Uganda. Methods: We used four survey rounds of data collected from July 2011-May 2018 from non-migrant participants aged 15-49 years in the Rakai Community Cohort Study, an open, population-based cohort. Non-migrants were individuals with no evidence of migration between surveys or at the prior survey. The primary exposure, household migration, was assessed using census data and defined as ≥1 household member migrating in or out of the house from another community between surveys (∼18 months). Incident HIV cases tested positive following a negative result at the preceding visit. Incidence rate ratios (IRR) with 95% confidence intervals were estimated using Poisson regression with generalized estimating equations and robust standard errors. Analyses were stratified by gender, migration into or out of the household, and the relationship between non-migrants and migrants (i.e., any household migration, spouse, child). Findings: Overall, 11,318 non-migrants (5,674 women) were followed for 37,320 person-years. 28% (6,059/21,370) of non-migrant person-visits had recent migration into or out of the household, and 240 HIV incident cases were identified in non-migrating household members. Overall, non-migrants in migrant households were not at greater risk of acquiring HIV. However, HIV incidence among men was significantly higher when the spouse had recently migrated in (adjIRR:2·12;95%CI:1·05-4·27) or out (adjIRR:4·01;95%CI:2·16-7·44) compared to men with no spousal migration. Women with in- and out-migrant spouses also had higher HIV incidence, but results were not statistically significant. Interpretation: HIV incidence is higher among non-migrating persons with migrant spouses, especially men. Targeted HIV testing and prevention interventions such as pre-exposure prophylaxis could be considered for those with migrant spouses. Funding: National Institutes of Health, US Centers for Disease Control and Prevention. Research in context: We searched PubMed for studies focused on HIV acquisition, prevalence or sexual behaviors among non-migrants who lived with migrants in sub-Saharan Africa (SSA) using search terms such as "HIV", "Emigration and Immigration", "family", "spouses", "household", "parents", and "children". Despite high levels of migration and an established association with HIV risk in SSA, there is limited data on the broader societal impacts of migration on HIV acquisition risk among non-migrant populations directly impacted by it.There has been only one published study that has previously evaluated impact of migration on HIV incidence among non-migrating persons in sub-Saharan Africa. This study, which exclusively assessed spousal migration, was conducted in Tanzania more than two decades earlier prior to HIV treatment availability and found that non-migrant men with long-term mobile partners were more than four times as likely to acquire HIV compared to men who had partners that were residents. To the best of our knowledge, this is the first study to examine the effect of non-spousal migration, including any household migration and child migration, on HIV incidence among non-migrants. Added value of this study: In this study, we used data from the Rakai Community Cohort Study (RCCS), a population-based HIV surveillance cohort to measure the impact of migration on HIV incidence for non-migrant household members. The RCCS captures HIV incident events through regular, repeat HIV testing of participants and migration events through household censuses. Our study adds to the current literature by examining the general effect of migration in the household on HIV incidence in addition to child, and spousal migration. Using data from over 11,000 non-migrant individuals, we found that spousal, but not other types of household migration, substantially increased HIV risk among non-migrants, especially among men. Taken together, our results suggest that spousal migration may be associated with an increased risk of HIV acquisition in the period surrounding and immediately after spousal migration. Implications of all the available evidence: Our findings suggest that spousal migration in or out of the household is associated with greater HIV incidence. Targeted HIV testing and prevention interventions such as pre-exposure prophylaxis could be considered for men with migrant spouses.

Performance of the South African triage score among HIV positive individuals presenting to an emergency department.

Introduction: Over a quarter of patients presenting to South African Emergency Centres (EC) have concurrent human immunodeficiency virus (HIV), yet it is unclear how this impacts their presenting complaints, the severity of illness, and overall resource needs in the EC. The primary objective of this study was to compare the performance of the South African Triage Score (SATS) in people living with HIV (PLWH) compared to HIV-negative patients. Secondary objectives included comparing the presentation characteristics and resource utilisation of these populations. Methods: A prospective cross-sectional observational study was conducted in the Livingstone Hospital EC, Gqeberha, South Africa, to compare triage designation and clinical outcomes in PLWH and HIV-negative patients. In this six-week study, all eligible patients received point-of-care HIV testing and extensive data abstraction, including SATS designation and EC clinical course. Descriptive statistical analysis was completed, and a log-binomial model was used to examine the association between HIV status and clinical outcomes using crude (unadjPR) and adjusted prevalence ratios (adjPR). Results: During the study period, 755 adult patients who consented to a POC HIV test were enrolled, of which 193 (25.6%) were HIV positive. HIV-positive patients were significantly more likely to be admitted compared to their HIV-negative counterparts when triaged as low acuity (adjPR 1.48, 95% CI 1.14-1.92, (p=0.003)). HIV-positive patients were also significantly more likely to receive laboratory testing when triaged as low acuity (adjPR 1.31, 95% CI 1.08-1.59 (p=0.006)) and as high acuity (adjPR 1.38, 95% CI 1.08-1.59 (p=0.034)) compared to HIV negative patients of the same triage categories. Conclusion: In our study, PLWH, compared to HIV-negative patients in the same category, were more likely to be admitted and require more EC resources, thus alluding to possible under triage of HIV-positive patients under the current SATS algorithm.

Determining the prevalence of tuberculosis in emergency departments in the Eastern Cape region of South Africa and the utility of the World Health Organization tuberculosis screening tool.

BACKGROUND: South Africa (SA) faces a significant tuberculosis (TB) burden complicated by high rates of HIV-TB co-infection. In SA, emergency departments (EDs) play an important role in screening for TB. OBJECTIVES: To determine the prevalence of TB in the ED and the effectiveness of the World Health Organization (WHO) TB screening tool. METHODS: This was a cross-sectional observational study, conducted in the ED at Livingstone Hospital, Port Elizabeth, from 4 June to 15 July 2018. All patients aged >18 years and able to consent were administered the WHO TB screening questions and underwent a point-of-care HIV test and demographic data collection. Patients were followed up for 1 year and tracked in the National Health Laboratory Service database to determine TB status using laboratory testing. RESULTS: Over the study period, 790 patients were enrolled. Overall, 121 patients (15.3%) were TB-positive, with 46 (38.0%) diagnosed after presenting to the ED and 75 (62.0%) with a previous TB history determined by self-report or confirmed laboratory testing. A greater proportion of the TB-positive patients were HIV-positive (49.6%) compared with the TB-negative population (24.8%). TB-positive individuals were more likely to present to the ED with a chief complaint of shortness of breath (SoB) (18.2%) compared with the TB-negative population (10.5%). Overall, the WHO TB screening tool had poor sensitivity (46.5%) and specificity (62.5%) for identifying TB-positive patients in the ED. A multiple logistic regression analysis, controlled for age and sex, showed HIV status (odds ratio (OR) 2.81; p<0.001) and SoB (OR 2.19; p<0.05) to be significant predictors of TB positivity. Adding positive HIV status and a presenting complaint of SoB increased sensitivity to 78.3%. CONCLUSIONS: EDs in SA face a high burden of TB. While WHO screening guidelines identify some of these patients, including routine HIV testing in the ED could significantly affect the number of TB diagnoses made.

Immune response to the hepatitis B vaccine among HIV-infected adults in Uganda.

BACKGROUND: Co-infection with hepatitis B virus (HBV) and human immunodeficiency virus (HIV) is common in sub-Saharan Africa (SSA) and can rapidly progress to cirrhosis and hepatocellular carcinoma. Recent data demonstrate ongoing HBV transmission among HIV-infected adults in SSA, suggesting that complications of HIV/HBV co-infection could be prevented with HBV vaccination. Because HBV vaccine efficacy is poorly understood among HIV-infected persons in SSA, we sought to characterize the humoral response to the HBV vaccine in HIV-seropositive Ugandan adults. METHODS: We enrolled HIV-infected adults in Kampala, Uganda without serologic evidence of prior HBV infection. Three HBV vaccine doses were administered at 0, 1 and 6 months. Anti-HBs levels were measured 4 weeks after the third vaccine dose. "Response" to vaccination was defined as anti-HBs levels ≥ 10 IU/L and "high response" as ≥ 100 IU/L. Regression analysis was used to determine predictors of response. RESULTS: Of 251 HIV-positive adults screened, 132 (53%) had no prior HBV infection or immunity and were enrolled. Most participants were women [89 (67%)]; median (IQR) age was 32 years (27-41), and 68 (52%) had received antiretroviral therapy (ART) for > 3 months. Median (IQR) CD4 count was 426 (261-583), and 64 (94%) of the 68 receiving ART had undetectable plasma HIV RNA. Overall, 117 (92%) participants seroconverted to the vaccine (anti-HBs ≥ 10 IU/L), with 109 (86%) participants having high-level response (anti-HBs ≥ 100 IU/L). In multivariate analysis, only baseline CD4 > 200 cells/mm3 was associated with response [OR = 6.97 (1.34-34.71), p = 0.02] and high-level response [OR = 4.25 (1.15-15.69)], p = 0.03]. CONCLUSION: HBV vaccination was effective in eliciting a protective humoral response, particularly among those with higher CD4 counts. Half of the screened patients did not have immunity to HBV infection, suggesting a large at-risk population for HBV infection among HIV-positive adults in Uganda. Our findings support including HBV vaccination as part of routine care among HIV-positive adults.

Impact of endemic HIV on emergency care service delivery in South Africa.

BACKGROUND: South Africa (SA) has the highest burden of HIV in the world. This study sought to evaluate the impact of high HIV prevalence on the burden of disease in an emergency department (ED). OBJECTIVES: To determine the burden of comorbidities in HIV-positive emergency care patients, their demographic profiles and severity of illness were compared with the general ED population in order to make recommendations for resource allocation and training in EDs in SA. METHODS: A prospective cross-sectional observational study was conducted from June 2017 to July 2018 in three EDs in Eastern Cape Province. All eligible patients (aged ≥18 years, fully conscious and clinically stable) presenting to the ED during the 6-week study period were approached and asked to give consent for a point-of-care HIV test and collection of demographic information. Simple descriptive statistics were used to analyse data. Log binomial and Poisson models were fitted to estimate prevalence ratios (PRs). RESULTS: Over the total study period, 8 000 patients presented to the ED for care across all sites and 3 537 patients were enrolled. The HIV status of 2 901 individuals (82.0%) was determined. Of those who were screened, 811 (28.0%) were identified as HIV-positive. Medical complaints were more common in HIV-positive patients (n=586, 72.3%) than in trauma patients (n=225, 27.7%). In comparison, HIV-negative patients reported fewer medical complaints (n=1 137, 54.4%) and more trauma (n=953, 45.6%) (p<0.001). HIV-positive patients were more likely to have a life-threatening emergency (n=192, 23.7%) (p=0.004), to be critically ill by triage score (p<0.001) and to be admitted to the hospital (p<0.001) than those who were HIV-negative. Despite high acuity overall, people living with HIV/AIDS were significantly less likely to be deemed critically ill according to vital signs (adjusted PR 0.94; p=0.046). CONCLUSIONS: While EDs in SA provide care to high volumes of patients with trauma-related injuries, in areas where HIV prevalence is highest, patients are more likely to present with acute medical emergencies. Providers of emergency care in SA need to be well versed in the management of HIV and associated complications.

Evaluation of multiplex real-time PCR for detection of Haemophilus ducreyi, Treponema pallidum, herpes simplex virus type 1 and 2 in the diagnosis of genital ulcer disease in the Rakai District, Uganda.

OBJECTIVE: To develop a real-time PCR assay that reliably and accurately detects the predominant sexually transmitted aetiological agents of genital ulcer disease (GUD) (Haemophilus ducreyi, Treponema pallidum and herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2)) and to assess the use of real-time PCR diagnostic testing in a rural African field site. METHODS: Two multiplex real-time PCR reactions were used to detect H ducreyi/and HSV-1/HSV-2 in ulcer swabs from 100 people with symptomatic genital ulcers in rural Rakai, Uganda. Results were compared with syphilis, HSV-1 and HSV-2 serology. RESULTS: Of 100 GUD samples analysed from 43 HIV positive and 57 HIV negative individuals, 71% were positive for one or more sexually transmitted infection (STI) pathogens by real-time PCR (61% for HSV-2, 5% for T pallidum, 3% for HSV-1, 1% for H ducreyi and 1% for dual H ducreyi/HSV-2). The frequency of HSV in genital ulcers was 56% (32/57) in HIV negative individuals and 77% (33/43) in HIV positive individuals (p = 0.037). Assay reproducibility was evaluated by repeat PCR testing in the USA with 96% agreement (kappa = 0.85). CONCLUSIONS: STI pathogens were detected in the majority of GUD swab samples from symptomatic patients in Rakai, Uganda, by real-time PCR. HSV-2 was the predominant cause of genital ulcers. Real-time PCR technology can provide sensitive, rapid and reproducible evaluation of GUD aetiology in a resource-limited setting.

Aetiology of genital ulcer disease in female partners of male participants in a circumcision trial in Uganda.

HIV acquisition is associated with herpes simplex virus type 2 (HSV-2) infection and genital ulcer disease (GUD). Three randomized control trials demonstrated that male circumcision significantly decreases HIV, HSV-2, human papillomavirus and self-reported GUD among men. GUD is also decreased among female partners of circumcised men, but it is unknown whether male circumcision status affects GUD pathogens in female partners. For the evaluation of GUD aetiology, two separate multiplex assays were performed to detect Haemophilus ducreyi, Treponema pallidum, HSV-1 and HSV-2. Of all the female GUD swabs evaluated, 67.5% had an aetiology identified, and HSV-2 was the primary pathogen detected (96.3%). However, there was no difference in the proportion of ulcers due to HSV-2 or other pathogens between female partners of circumcised men (11/15, 73.3%) compared with uncircumcised men (15/25, 60.0%, P = 0.39). The seroprevalence of HSV-2 is high in this population and therefore most of the detected HSV-2 infections represent reactivation. Since GUD is associated with HIV acquisition and one-third of GUD in this study did not have an aetiological agent identified, further research is needed to better understand the aetiology of GUD in Africa, and its relationship to circumcision and HIV infection.

Sustained positive impact on tuberculosis treatment outcomes of TB-HIV integrated care in Uganda.

To examine tuberculosis (TB) treatment outcomes from a long-term TB-HIV (human immunodeficiency virus) integrated model of care at the Infectious Diseases Institute Clinic, Kampala, Uganda. We included HIV-positive adults who were new TB cases initiated on anti-tuberculosis treatment between 2009 and 2015 during TB-HIV integration. Trends in TB treatment outcomes and TB-associated deaths were analyzed using respectively the χ² trend test and Kaplan-Meier methods. The analysis involved 1318 cases: most patients were female (>50%); the median age ranged from 34 to 36 years, and >60% were late presenters (CD4 count <200 cells/µl), with a median CD4 cell count of 100-146 cells/µl at TB diagnosis. TB treatment success (cured or treatment completed) was 67-76%. Loss to follow-up (LTFU) declined systematically from 7% in 2010 to 3.4% in 2015 (P < 0.01). Antiretroviral therapy (ART) initiation during the intensive phase improved from 47% in 2009 to 97% in 2015 (P < 0.01). The mortality rate was >15% over time, and the probability of death at month 2 of anti-tuberculosis treatment was 52% higher among late presenters than in early presenters (13% vs. 6%, P < 0.01). Significant LTFU improvement and prompt ART initiation could be due to well-implemented TB-HIV integration care; however, static TB-associated deaths may be due to late presentation. .

A method for the improved detection of aerosolized influenza viruses and the male-specific (F+) RNA coliphage MS2.

The detection of aerosolized viruses can serve as an important surveillance and control tool in agriculture, human health, and environmental settings. Here, we adapted an anion exchange resin-based method, initially developed to concentrate negatively charged viruses from water, to liquid impingement-based bioaerosol sampling. In this method, aerosolized viruses are collected in a 20ml liquid sample contained within widely used impingers, BioSamplers (SKC Inc., Eighty Four, PA), and further concentrated via adsorption to an anion exchange resin that is suspended within this liquid. Viral nucleic acids are then extracted from the resin to facilitate molecular analyses through a reduction in the effective sample volume. For this study, various quantities of two negatively charged viruses, type A and type B influenza viruses (FluMist Quadrivalent vaccine) and the male-specific (F+) RNA coliphage MS2 (MS2), were nebulized into a custom-built bioaerosolization chamber, and sampled using BioSamplers with and without anion exchange resin. Compared to direct testing of the BioSampler liquid, detection was improved by 6.77× and 3.33× for type A and type B influenza viruses, respectively, by using the anion exchange resin. For MS2, the anion exchange resin method allowed for an average improvement in detection of 8.26×.

Total dust and endotoxin in poultry operations: comparison between cage and floor housing and respiratory effects in workers.

OBJECTIVE: The objective of this study was to assess respiratory outcomes and environmental exposure levels of workers in cage-housed and floor-housed poultry operations. METHODS: Poultry operations were evaluated for total dust, endotoxin, and ammonia, and respiratory symptoms and lung function tests of workers were conducted. RESULTS: Workers in floor-housed poultry operations had significantly greater exposures to total dust and ammonia, whereas workers from cage-housed poultry operations reported greater frequency of current and chronic symptoms overall and significantly greater current and chronic phlegm (39% vs 18% and 40% vs 11%, respectively). Endotoxin concentration (EU/mg) was a significant predictor (P = 0.05) of chronic phlegm for all poultry workers. CONCLUSIONS: Greater endotoxin concentration in the presence of significantly lower total dust, in conjunction with greater respiratory symptoms in workers from cage-housed poultry operations, as compared with workers from floor-housed poultry operations, appears to indicate that differences in environmental exposures may impact respiratory outcomes of workers.

Distinct cis-acting sequences are required for the germination and sugar responses of the cucumber isocitrate lyase gene.

Recent data have shown that distinct DNA sequence elements direct the germination and sugar responses of the cucumber (Cucumis sativus, L.) malate synthase (Ms) gene (Sarah et al. (1996) Mol. Gen. Genet., 250, 153-161). Such information is, however, lacking for the isocitrate lyase (Icl) gene which is coordinately regulated with Ms. Deletions from the 5' end of the Icl promoter were therefore created specifically to address this question. Analysis of expression in seeds of transgenic Nicotiana plumbaginifolia plants showed that whereas a promoter sequence of 2.9 kilobases (kb) produced a normal germination response, deletion to -1568 base pairs (bp) dramatically reduced this response. Examination of the sugar response employed a transgenic cucumber root system. In this case, the 2900 bp and 1568 bp promoters both gave a strong sugar response, but further deletion to -1367 bp eliminated the response. Therefore, the germination and sugar responses of the Icl gene require distinct cis-acting elements, located respectively upstream and downstream of -1568 bp. This observation is consistent with distinct signal transduction systems regulating gene expression in each case.

Inheritance and variation in eggshell patterning in the great tit Parus major.

The inheritance of patterns on avian eggshells is central to understanding the evolution of traits such as egg mimicry (e.g. in cuckoos). Yet little is known about the inheritance, or indeed function, of eggshell patterns. It has long been believed that the evolution of eggshell pattern mimicry required that patterns be determined by genes situated on the female-specific W chromosome. However, it has never been demonstrated for any bird that egg pattern traits (rather than ground colour) are female sex linked, or indeed that they are inherited. We studied the inheritance of three measures of egg-pigment patterns in a wild great tit population. Egg patterns were female specific but unrelated to female attributes such as age or condition and showed only weak environmental effects. Eggs of daughters resembled those of both their mothers and maternal grandmothers, but not of their paternal grandmothers. We conclude that this is the first demonstration of female sex-linked inheritance of avian eggshell patterning, so raising the probability that such a system operates in egg mimics and their hosts.

Catecholamines in turkeys with alcohol-induced cardiomyopathy.

Although alcoholic cardiomyopathy has been difficult to reproduce in animals, turkeys fed 5% ethanol develop a dilated congestive cardiomyopathy. We therefore used this model to examine the adrenergic response to left ventricular dysfunction induced by alcohol. In normal turkeys, norepinephrine in kidneys decreased markedly with age from 1 day to 2 mo, with a similar but less dramatic decrease in cardiac norepinephrine. By 2 mo, chronic alcohol ingestion depleted cardiac norepinephrine compared with controls (217 +/- 22 vs. 316 +/- 41 ng/g, P < 0.05), even though cardiac norepinephrine is relatively low in turkeys compared with many other animals and humans. Norepinephrine in aorta was also decreased with alcohol administration, but kidney norepinephrine was unaffected. Dopamine was unaltered in any of the organs studied. Plasma norepinephrine is normally high in turkeys with arterial levels greater than venous (2,898 +/- 746 vs. 1,987 +/- 531 pg/ml at 2 mo). Venous plasma norepinephrine did not differ from control (2,595 +/- 547 pg/ml) after 2 mo of alcohol. Thus, as in humans, cardiomyopathy in alcohol-fed turkeys is associated with reduced cardiac norepinephrine, but unlike humans with cardiomyopathy, circulating norepinephrine remains normal.

Impaired vision for binocular tasks after unilateral optic nerve regeneration in the frog Litoria moorei.

Behavioural responses to objects in the binocular field were examined in frogs with one regenerate and one intact optic nerve. Data were compared to those for normal controls and for frogs with vision via one intact optic nerve. During prey acquisition, frogs with regenerated optic nerves underestimated the distance to the prey on their first strike; as a consequence, the regenerate series made several attempts to achieve a successful prey capture. By contrast, normal frogs and those using only one eye struck accurately at the prey and usually captured it on the first attempt. However, frogs using only one eye struck from a closer distance than either the regenerate or normal series. Frogs with regenerated optic nerves also made more errors than either of the other series when leaping through a set of closely spaced horizontally aligned rods. Our results show that prey capture and the negotiation of horizontally aligned rods is impaired in animals using one regenerated and one intact optic nerve as compared to both normal frogs and those using only one eye. We suggest that the poor visual performance for frogs with one regenerated and one intact optic nerve for tasks presented in the binocular field is related to the integration of a degraded and a normal image within the visual centres.

Effectiveness of roll-over protective structures in reducing farm tractor fatalities.

OBJECTIVE: The purpose of this systematic review was to evaluate the effectiveness of roll-over protection structures (ROPS) as an engineering control for prevention of fatalities from farm tractor roll-overs. METHODS: Using a systematic approach to literature searching, relevant studies from peer-reviewed journals, technical and government reports, and unpublished reports were retrieved. Studies meeting initial criteria for possible inclusion were screened to determine whether they addressed the review topic (ROPS), included comparison data and included outcomes data such as injury or fatality. Articles that evaluated the use and impact of ROPS on operators of agricultural tractors were reviewed. Outcomes included two primary categories: implementation of ROPS and fatalities. MAIN RESULTS: Of a total 207 citations reviewed, 53 met initial screening criteria and 21 studies were included in this review. Farm tractor roll-overs result in approximately 200 fatalities per year in the United States. ROPS or crush-proof cabs, which are designed to protect the farmer during a roll-over incident, are currently used on only about 50% of the estimated 4.8 million tractors in the United States. A significant proportion of tractors built after 1985 (when manufacturers began implementing a voluntary ROPS standard) have had ROPS removed. Evidence from Sweden and other Northern European countries clearly demonstrates that ROPS can essentially eliminate roll-over fatalities. In the United States, the only fatalities associated with roll-overs of ROPS-equipped tractors occurred when farmers did not use a seatbelt to hold them within the protective envelope of the ROPS. Estimates of costs of programs to retrofit older tractors with ROPS range from approximately $500,000 to $900,000 per life saved, which is comparable to other accepted life-saving interventions. CONCLUSIONS: Future research efforts should include the development of collapsible and telescoping ROPS that can be used in low clearance areas such as dairy barns and fruit orchards. ROPS retrofits also need to be developed for many older tractor models. Effective educational and incentive programs need to be developed to increase the acceptance and use of ROPS among U.S. farmers. A national policy should be implemented to ensure that all tractors operated in the United States are equipped with ROPS or crush-proof cabs.

Risk factors for injury in rural Iowa: round one of the Keokuk County Rural Health Study.

BACKGROUND: Unintentional injuries represent a major cause of morbidity and mortality in rural communities. This study aimed to determine the distribution of injury risk factors in a rural Iowa community and to identify the rural subgroups at highest risk for injury. METHODS: We reported on 1583 participants, aged > or =25 years, from Round One of the Keokuk County Rural Health Study, a longitudinal panel study of a rural community. The self-reported data were collected during face-to-face interviews. RESULTS: Our data suggested that several risk factors for injury are not uniformly distributed among rural populations. Male farmers were significantly less likely to wear their seatbelts than townspeople or rural nonfarmers. However, farm women were as likely to wear seatbelts as other women. Both male and female farmers were more likely to use all-terrain vehicles than townspeople or rural nonfarmers. In contrast, townspeople were more likely to ride bicycles than either farmers or rural nonfarmers. Townspeople were less likely to have firearms in their homes than either farmers or rural nonfarmers. Farmers were most likely to have fired a gun in the last year. Male farmers aged <65 years were less than half as likely as other men the same age to report a history of alcohol abuse. Binge drinking was equally frequent among farmers, rural nonfarmers, and townspeople. CONCLUSIONS: These differences in risk behavior in a rural county suggest the possibility of targeting specific rural injury prevention interventions at those with the highest risk for dangerous behavior.

Central nervous system myelin: structure, function, and pathology.

Multiple sclerosis (MS) and a number of related distinctive diseases are characterized by the active degradation of central nervous system (CNS) myelin, an axonal sheath comprised essentially of proteins and lipids. These demyelinating diseases appear to arise from complex interactions of genetic, immunological, infective, and biochemical mechanisms. While circumstances of MS etiology remain hypothetical, one persistent theme involves recognition by the immune system of myelin-specific antigens derived from myelin basic protein (MBP), the most abundant extrinsic myelin membrane protein, and/or another equally susceptible myelin protein or lipid component. Knowledge of the biochemical and physical-chemical properties of myelin proteins and lipids, particularly their composition, organization, structure, and accessibility with respect to the compacted myelin multilayers, thus becomes central to the understanding of how and why these antigens become selected during the development of MS. This review focuses on current understanding of the molecular basis underlying demyelinating disease as it may relate to the impact of the various protein and lipid components on myelin morphology; the precise molecular architecture of this membrane as dictated by protein-lipid and lipid-lipid interactions; and the relationship, if any, between the protein/lipid components and the destruction of myelin in pathological situations.