Burden of disease attributable to unsafe drinking water, sanitation, and hygiene in domestic settings: a global analysis for selected adverse health outcomes

BACKGROUND

Assessments of disease burden are important to inform national, regional, and global strategies and to guide investment. We aimed to estimate the drinking water, sanitation, and hygiene (WASH)-attributable burden of disease for diarrhoea, acute respiratory infections, undernutrition, and soil-transmitted helminthiasis, using the WASH service levels used to monitor the UN Sustainable Development Goals (SDGs) as counterfactual minimum risk-exposure levels.

METHODS

We assessed the WASH-attributable disease burden of the four health outcomes overall and disaggregated by region, age, and sex for the year 2019. We calculated WASH-attributable fractions of diarrhoea and acute respiratory infections by country using modelled WASH exposures and exposure-response relationships from two updated meta-analyses. We used the WHO and UNICEF Joint Monitoring Programme for Water Supply, Sanitation and Hygiene public database to estimate population exposure to different WASH service levels. WASH-attributable undernutrition was estimated by combining the population attributable fractions (PAF) of diarrhoea caused by unsafe WASH and the PAF of undernutrition caused by diarrhoea. Soil-transmitted helminthiasis was fully attributed to unsafe WASH.

FINDINGS

We estimate that 1·4 (95% CI 1·3-1·5) million deaths and 74 (68-80) million disability-adjusted life-years (DALYs) could have been prevented by safe WASH in 2019 across the four designated outcomes, representing 2·5% of global deaths and 2·9% of global DALYs from all causes. The proportion of diarrhoea that is attributable to unsafe WASH is 0·69 (0·65-0·72), 0·14 (0·13-0·17) for acute respiratory infections, and 0·10 (0·09-0·10) for undernutrition, and we assume that the entire disease burden from soil-transmitted helminthiasis was attributable to unsafe WASH.

INTERPRETATION

WASH-attributable burden of disease estimates based on the levels of service established under the SDG framework show that progress towards the internationally agreed goal of safely managed WASH services for all would yield major public-health returns.

FUNDING

WHO and Foreign, Commonwealth & Development Office.

Effectiveness of interventions to improve drinking water, sanitation, and handwashing with soap on risk of diarrhoeal disease in children in low-income and middle-income settings: a systematic review and meta-analysis

BACKGROUND

Estimates of the effectiveness of water, sanitation, and hygiene (WASH) interventions that provide high levels of service on childhood diarrhoea are scarce. We aimed to provide up-to-date estimates on the burden of disease attributable to WASH and on the effects of different types of WASH interventions on childhood diarrhoea in low-income and middle-income countries (LMICs).

METHODS

In this systematic review and meta-analysis, we updated previous reviews following their search strategy by searching MEDLINE, Embase, Scopus, Cochrane Library, and BIOSIS Citation Index for studies of basic WASH interventions and of WASH interventions providing a high level of service, published between Jan 1, 2016, and May 25, 2021. We included randomised and non-randomised controlled trials conducted at household or community level that matched exposure categories of the so-called service ladder approach of the Sustainable Development Goal (SDG) for WASH. Two reviewers independently extracted study-level data and assessed risk of bias using a modified Newcastle-Ottawa Scale and certainty of evidence using a modified Grading of Recommendations, Assessment, Development, and Evaluation approach. We analysed extracted relative risks (RRs) and 95% CIs using random-effects meta-analyses and meta-regression models. This study is registered with PROSPERO, CRD42016043164.

FINDINGS

19 837 records were identified from the search, of which 124 studies were included, providing 83 water (62 616 children), 20 sanitation (40 799 children), and 41 hygiene (98 416 children) comparisons. Compared with untreated water from an unimproved source, risk of diarrhoea was reduced by up to 50% with water treated at point of use (POU): filtration (n=23 studies; RR 0·50 [95% CI 0·41-0·60]), solar treatment (n=13; 0·63 [0·50-0·80]), and chlorination (n=25; 0·66 [0·56-0·77]). Compared with an unimproved source, provision of an improved drinking water supply on premises with higher water quality reduced diarrhoea risk by 52% (n=2; 0·48 [0·26-0·87]). Overall, sanitation interventions reduced diarrhoea risk by 24% (0·76 [0·61-0·94]). Compared with unimproved sanitation, providing sewer connection reduced diarrhoea risk by 47% (n=5; 0·53 [0·30-0·93]). Promotion of handwashing with soap reduced diarrhoea risk by 30% (0·70 [0·64-0·76]).

INTERPRETATION

WASH interventions reduced risk of diarrhoea in children in LMICs. Interventions supplying either water filtered at POU, higher water quality from an improved source on premises, or basic sanitation services with sewer connection were associated with increased reductions. Our results support higher service levels called for under SDG 6. Notably, no studies evaluated interventions that delivered access to safely managed WASH services, the level of service to which universal coverage by 2030 is committed under the SDG.

FUNDING

WHO, Foreign, Commonwealth & Development Office, and National Institute of Environmental Health Sciences.

The implications of three major new trials for the effect of water, sanitation and hygiene on childhood diarrhea and stunting: a consensus statement

BACKGROUND

Three large new trials of unprecedented scale and cost, which included novel factorial designs, have found no effect of basic water, sanitation and hygiene (WASH) interventions on childhood stunting, and only mixed effects on childhood diarrhea. Arriving at the inception of the United Nations' Sustainable Development Goals, and the bold new target of safely managed water, sanitation and hygiene for all by 2030, these results warrant the attention of researchers, policy-makers and practitioners.

MAIN BODY

Here we report the conclusions of an expert meeting convened by the World Health Organization and the Bill and Melinda Gates Foundation to discuss these findings, and present five key consensus messages as a basis for wider discussion and debate in the WASH and nutrition sectors. We judge these trials to have high internal validity, constituting good evidence that these specific interventions had no effect on childhood linear growth, and mixed effects on childhood diarrhea. These results suggest that, in settings such as these, more comprehensive or ambitious WASH interventions may be needed to achieve a major impact on child health.

CONCLUSION

These results are important because such basic interventions are often deployed in low-income rural settings with the expectation of improving child health, although this is rarely the sole justification. Our view is that these three new trials do not show that WASH in general cannot influence child linear growth, but they do demonstrate that these specific interventions had no influence in settings where stunting remains an important public health challenge. We support a call for transformative WASH, in so much as it encapsulates the guiding principle that - in any context - a comprehensive package of WASH interventions is needed that is tailored to address the local exposure landscape and enteric disease burden.

Mechanical characterization of structurally porous biomaterials built via additive manufacturing: experiments, predictive models, and design maps for load-bearing bone replacement implants

Porous biomaterials can be additively manufactured with micro-architecture tailored to satisfy the stringent mechano-biological requirements imposed by bone replacement implants. In a previous investigation, we introduced structurally porous biomaterials, featuring strength five times stronger than commercially available porous materials, and confirmed their bone ingrowth capability in an in vivo canine model. While encouraging, the manufactured biomaterials showed geometric mismatches between their internal porous architecture and that of its as-designed counterpart, as well as discrepancies between predicted and tested mechanical properties, issues not fully elucidated. In this work, we propose a systematic approach integrating computed tomography, mechanical testing, and statistical analysis of geometric imperfections to generate statistical based numerical models of high-strength additively manufactured porous biomaterials. The method is used to develop morphology and mechanical maps that illustrate the role played by pore size, porosity, strut thickness, and topology on the relations governing their elastic modulus and compressive yield strength. Overall, there are mismatches between the mechanical properties of ideal-geometry models and as-manufactured porous biomaterials with average errors of 49% and 41% respectively for compressive elastic modulus and yield strength. The proposed methodology gives more accurate predictions for the compressive stiffness and the compressive strength properties with a reduction of the average error to 11% and 7.6%. The implications of the results and the methodology here introduced are discussed in the relevant biomechanical and clinical context, with insight that highlights promises and limitations of additively manufactured porous biomaterials for load-bearing bone replacement implants.

STATEMENT OF SIGNIFICANCE

In this work, we perform mechanical characterization of load-bearing porous biomaterials for bone replacement over their entire design space. Results capture the shift in geometry and mechanical properties between as-designed and as-manufactured biomaterials induced by additive manufacturing. Characterization of this shift is crucial to ensure appropriate manufacturing of bone replacement implants that enable biological fixation through bone ingrowth as well as mechanical property harmonization with the native bone tissue. In addition, we propose a method to include manufacturing imperfections in the numerical models that can reduce the discrepancy between predicted and tested properties. The results give insight into the use of structurally porous biomaterials for the design and additive fabrication of load-bearing implants for bone replacement.

Incidences and Costs of Illness for Diarrhea and Acute Respiratory Infections for Children < 5 Years of Age in Rural Bangladesh

AbstractUnderstanding illness costs associated with diarrhea and acute respiratory infections (ARI) could guide prevention and treatment strategies. This study aimed to determine incidence of childhood diarrhea and ARI and costs of homecare, hospitalization, and outpatient treatment by practitioner type in rural Bangladesh. From each of 100 randomly selected population clusters we sampled 17 households with at least one child < 5 years of age. Childhood diarrhea incidence was 3,451 and ARI incidence was 5,849/1,000 child-years. For diarrhea and ARI outpatient care per 1,000 child-years, parents spent more on unqualified ($2,361 and $4,822) than qualified health-care practitioners ($113 and $947). For outpatient care, visits to unqualified health-care practitioners were at least five times more common than visits to qualified practitioners. Costs for outpatient care treatment by unqualified health-care practitioners per episode of illness were similar to those for qualified health-care practitioners. Homecare costs were similar for diarrhea and ARI ($0.16 and $0.24) as were similar hospitalization costs per episode of diarrhea and ARI ($35.40 and $37.76). On average, rural Bangladeshi households with children < 5 years of age spent 1.3% ($12 of $915) of their annual income managing diarrhea and ARI for those children. The majority of childhood illness management cost comprised visits to unqualified health-care practitioners. Policy makers should consider strategies to increase the skills of unqualified health-care practitioners, use community health workers to provide referral, and promote homecare for diarrhea and ARI. Incentives to motivate existing qualified physicians who are interested to work in rural Bangladesh could also be considered.

Microbiological Contamination of Drinking Water Associated with Subsequent Child Diarrhea

We used a prospective, longitudinal cohort enrolled as part of a program evaluation to assess the relationship between drinking water microbiological quality and child diarrhea. We included 50 villages across rural Bangladesh. Within each village field-workers enrolled a systematic random sample of 10 households with a child under the age of 3 years. Community monitors visited households monthly and recorded whether children under the age of 5 years had diarrhea in the preceding 2 days. Every 3 months, a research assistant visited the household and requested a water sample from the source or container used to provide drinking water to the child. Laboratory technicians measured the concentration of Escherichia coli in the water samples using membrane filtration. Of drinking water samples, 59% (2,273/3,833) were contaminated with E. coli. Of 12,192 monthly follow-up visits over 2 years, mothers reported that their child had diarrhea in the preceding 2 days in 1,156 (9.5%) visits. In a multivariable general linear model, the log₁₀ of E. coli contamination of the preceding drinking water sample was associated with an increased prevalence of child diarrhea (prevalence ratio = 1.14, 95% CI = 1.05, 1.23). These data provide further evidence of the health benefits of improved microbiological quality of drinking water.

Renal Autotransplantation: 27-Year Experience at 2 Institutions

PURPOSE

Renal autotransplantation is an infrequently performed procedure. It has been used to manage complex ureteral disease, vascular anomalies and chronic kidney pain. We reviewed our 27-year experience with this procedure.

MATERIALS AND METHODS

This is a retrospective, observational study of 51 consecutive patients who underwent renal autotransplantation, including 29 at Oregon Health and Science University between 1986 and 2013, and 22 at Virginia Mason Medical Center between 2007 and 2012. Demographics, indications, operative details and followup data were collected. Early (30 days or less) and late (greater than 30 days) complications were graded according to the Clavien-Dindo system. Factors associated with complications and pain recurrence were evaluated using a logistic regression model.

RESULTS

The 51 patients underwent a total of 54 renal autotransplants. Median followup was 21.5 months. The most common indications were loin pain hematuria syndrome/chronic kidney pain in 31.5% of cases, ureteral stricture in 20.4% and vascular anomalies in 18.5%. Autotransplantation of a solitary kidney was performed in 5 patients. Laparoscopic nephrectomy was performed in 23.5% of cases. Median operative time was 402 minutes and median length of stay was 6 days. No significant difference was found between preoperative and postoperative plasma creatinine (p = 0.74). Early, high grade complications (grade IIIa or greater) developed in 14.8% of patients and 12.9% experienced late complications of any grade. Two graft losses occurred. Longer cold ischemia time was associated with complications (p = 0.049). Of patients who underwent autotransplantation for chronic kidney pain 35% experienced recurrence and 2 underwent transplant nephrectomy. No predictors of pain recurrence were identified.

CONCLUSIONS

The most common indications for renal autotransplantation were loin pain hematuria syndrome/chronic kidney pain, ureteral stricture and vascular anomalies in descending order. Kidney function was preserved postoperatively and 2 graft losses occurred. At a median followup of 13 months pain resolved in 65% of patients who underwent the procedure. Complication rates compared favorably with those of other major urological operations and cold ischemia time was the only predictor of postoperative complications.

Prospective quality-of-life outcomes for low-risk prostate cancer: Active surveillance versus radical prostatectomy

BACKGROUND

For patients with low-risk prostate cancer (PCa), active surveillance (AS) may produce oncologic outcomes comparable to those achieved with radical prostatectomy (RP). Health-related quality-of-life (HRQoL) outcomes are important to consider, yet few studies have examined HRQoL among patients with PCa who were managed with AS. In this study, the authors compared longitudinal HRQoL in a prospective, racially diverse, and contemporary cohort of patients who underwent RP or AS for low-risk PCa.

METHODS

Beginning in 2007, HRQoL data from validated questionnaires (the Expanded Prostate Cancer Index Composite and the 36-item RAND Medical Outcomes Study short-form survey) were collected by the Center for Prostate Disease Research in a multicenter national database. Patients aged ≤75 years who were diagnosed with low-risk PCa and elected RP or AS for initial disease management were followed for 3 years. Mean scores were estimated using generalized estimating equations adjusting for baseline HRQoL, demographic characteristics, and clinical patient characteristics.

RESULTS

Of the patients with low-risk PCa, 228 underwent RP, and 77 underwent AS. Multivariable analysis revealed that patients in the RP group had significantly worse sexual function, sexual bother, and urinary function at all time points compared with patients in the AS group. Differences in mental health between groups were below the threshold for clinical significance at 1 year.

CONCLUSIONS

In this study, no differences in mental health outcomes were observed, but urinary and sexual HRQoL were worse for patients who underwent RP compared with those who underwent AS for up to 3 years. These data offer support for the management of low-risk PCa with AS as a means for postponing the morbidity associated with RP without concomitant declines in mental health.

The Impact of Multiple Prostate Needle Biopsies on Long-Term Erectile Dysfunction

INTRODUCTION

The impact of transrectal ultrasound guided prostate needle biopsy on erectile dysfunction remains uncertain. We examined whether transrectal ultrasound guided prostate needle biopsy contributes to the development or worsening of erectile dysfunction as assessed by IIEF-5 scores in patients who underwent multiple prostate needle biopsies.

METHODS

The study population consisted of 826 men who underwent transrectal ultrasound guided 10 to 12-core prostate needle biopsy for suspicion or surveillance of prostate cancer. Men were evaluated for erectile dysfunction using the IIEF-5 questionnaire. Erectile dysfunction was modeled as a categorical variable, defined as any (0 to 20), mild (16 to 20), mild to moderate (11 to 15), moderate (6 to 10) or severe (0 to 5). The impact of multiple prostate needle biopsies was also evaluated.

RESULTS

Of 826 men who underwent prostate needle biopsy 240 (29%) had undergone 1 or more and 168 (20%) had undergone 2 or more biopsies. Mean patient age was 63 years and mean IIEF-5 score was 16. On univariate analysis age (OR 1.11, 95% CI 1.09-1.14, p <0.001), and 1 (OR 1.79, 95% CI 1.06-3.03, p=0.03) or 2 (OR 1.80, 95% CI 1.02-3.17, p=0.04) prior prostate needle biopsies were associated with erectile dysfunction. On multivariate analysis age alone was predictive of severe erectile dysfunction (OR 1.09, 95% CI 1.05-1.12, p=0.002). A repeat prostate needle biopsy within 12 months was associated with worse erectile dysfunction (OR 1.55, 95% CI 1.08-2.93, p=0.02). When long-term erectile function was evaluated, prostate needle biopsy was not significant after adjustment for covariates.

CONCLUSIONS

In the short term prostate needle biopsy may be important in predicting transient (less than 1 year) erectile dysfunction. However, in the long term prostate needle biopsy does not predict erectile dysfunction in aging men.

Modeling Management Strategies for Clinical Stage I Seminoma: Direct and Indirect Costs for the First 5 Years

INTRODUCTION

Clinical stage I seminoma can be managed with surveillance, chemotherapy or radiotherapy with similar survival rates. However, costs and side effects vary among these treatment modalities. We created a model to estimate the direct and indirect costs during the first 5 years of treatment for the 3 treatment strategies.

METHODS

Markov model based analyses were conducted to compare the costs of the 3 management strategies during the first 5 years. In this model clinicians and patients were assumed to be 100% compliant with the 2012 NCCN Guidelines® for testicular cancer. Model parameters were collected from the Washington State CHARS (Comprehensive Hospital Abstract Reporting System), published literature and Medicare reimbursement amounts. A 5% annual health inflation rate was assumed.

RESULTS

The model predicts an initial cost premium for carboplatin (1 cycle-$9,199.49; 2 cycles-$10,613.85) and radiotherapy ($9,532.80) compared with surveillance ($9,065.31). Radiotherapy (145.8 hours) and surveillance (123.0 hours) require more patient time than carboplatin (1 cycle-93.2 hours, 2 cycles-106.3 hours). When the direct and indirect costs are considered, the least expensive management strategy is surveillance.

CONCLUSIONS

Surveillance is the most cost-effective management strategy for clinical stage I seminoma during the first 5 years of treatment. Although not evaluated in this analysis, costs of late side effects associated with radiotherapy and chemotherapy should be considered. Due to potentially minimal late side effects and superior cost-effectiveness, surveillance represents a safe, cost-effective and time effective option for the management of stage I seminoma.

Burden of disease from inadequate water, sanitation and hygiene in low- and middle-income settings: a retrospective analysis of data from 145 countries

OBJECTIVE

To estimate the burden of diarrhoeal diseases from exposure to inadequate water, sanitation and hand hygiene in low- and middle-income settings and provide an overview of the impact on other diseases.

METHODS

For estimating the impact of water, sanitation and hygiene on diarrhoea, we selected exposure levels with both sufficient global exposure data and a matching exposure-risk relationship. Global exposure data were estimated for the year 2012, and risk estimates were taken from the most recent systematic analyses. We estimated attributable deaths and disability-adjusted life years (DALYs) by country, age and sex for inadequate water, sanitation and hand hygiene separately, and as a cluster of risk factors. Uncertainty estimates were computed on the basis of uncertainty surrounding exposure estimates and relative risks.

RESULTS

In 2012, 502,000 diarrhoea deaths were estimated to be caused by inadequate drinking water and 280,000 deaths by inadequate sanitation. The most likely estimate of disease burden from inadequate hand hygiene amounts to 297,000 deaths. In total, 842,000 diarrhoea deaths are estimated to be caused by this cluster of risk factors, which amounts to 1.5% of the total disease burden and 58% of diarrhoeal diseases. In children under 5 years old, 361,000 deaths could be prevented, representing 5.5% of deaths in that age group.

CONCLUSIONS

This estimate confirms the importance of improving water and sanitation in low- and middle-income settings for the prevention of diarrhoeal disease burden. It also underscores the need for better data on exposure and risk reductions that can be achieved with provision of reliable piped water, community sewage with treatment and hand hygiene.

Multi-criteria assessment of community-based fluoride-removal technologies for rural Ethiopia

Elevated concentrations of naturally-occurring fluoride in groundwater pose a serious health risk to millions of people living in the Ethiopian Rift Valley. In the absence of low-fluoride water resources of sufficient capacity, fluoride removal from drinking water is the accepted mitigation option. To date, five different community-level fluoride-removal technologies have been implemented in Ethiopia, although only a few units have been found in a functional state in the field. Which technology should be promoted and up-scaled is the subject of controversial debate amongst key stakeholders. This paper describes a multi-criteria decision analysis exercise, which was conducted with the participation of stakeholders in Ethiopia during a one-day workshop, to assess in an objective and transparent manner the available technology options. Criteria for technology comparison were selected and weighted, thus enabling the participants to assess the advantages and disadvantages of the different technologies and hear the views of other stakeholders. It was shown that there is no single most-preferable, technical solution for fluoride removal in Ethiopia. Selection of the most suitable solution depends on location-specific parameters and on the relative importance given to different criteria by the stakeholders involved. The data presented in this paper can be used as reference values for Ethiopia.

The Whitaker test

PURPOSE

The Whitaker test was conceived and developed by Roger H. Whitaker (May 25, 1939) while he was a resident at Cambridge University in the late 1960s and early 1970s. The test combines a urodynamic study with antegrade pyelography to measure the pressure differential between the renal pelvis and the bladder. The test can differentiate between patients with residual or recurrent obstruction and those with dilatation secondary to permanent changes in the musculature.

MATERIALS AND METHODS

We present the history of the Whitaker test and its place in modern practice.

RESULTS

It is useful in evaluating patients with questionable ureteropelvic or ureterovesical junction obstruction and primary defects in the ureteral musculature. It can also be used to determine when percutaneous nephrostomy tubes can be safely discontinued in postoperative patients.

CONCLUSION

The merit of the Whitaker test in comparison to other less invasive tests, specifically diuretic renography, is the subject of much debate. However, such debate erroneously presupposes that the tests are directly comparable, which they are not. The correct use for the Whitaker test is to assesses potential upper tract obstruction in equivocal cases and should only be utilized when equivocal results are obtained by other less invasive tests, obstruction is suspected in a poorly functioning kidney, a negative renogram with colic, intermittent obstruction, and percutaneous access already exists and the cause of dilatation needs investigating.

Assessing the impact of drinking water and sanitation on diarrhoeal disease in low- and middle-income settings: systematic review and meta-regression

OBJECTIVE

To assess the impact of inadequate water and sanitation on diarrhoeal disease in low- and middle-income settings.

METHODS

The search strategy used Cochrane Library, MEDLINE & PubMed, Global Health, Embase and BIOSIS supplemented by screening of reference lists from previously published systematic reviews, to identify studies reporting on interventions examining the effect of drinking water and sanitation improvements in low- and middle-income settings published between 1970 and May 2013. Studies including randomised controlled trials, quasi-randomised trials with control group, observational studies using matching techniques and observational studies with a control group where the intervention was well defined were eligible. Risk of bias was assessed using a modified Ottawa-Newcastle scale. Study results were combined using meta-analysis and meta-regression to derive overall and intervention-specific risk estimates.

RESULTS

Of 6819 records identified for drinking water, 61 studies met the inclusion criteria, and of 12,515 records identified for sanitation, 11 studies were included. Overall, improvements in drinking water and sanitation were associated with decreased risks of diarrhoea. Specific improvements, such as the use of water filters, provision of high-quality piped water and sewer connections, were associated with greater reductions in diarrhoea compared with other interventions.

CONCLUSIONS

The results show that inadequate water and sanitation are associated with considerable risks of diarrhoeal disease and that there are notable differences in illness reduction according to the type of improved water and sanitation implemented.

Prognostic value of ERG oncoprotein in prostate cancer recurrence and cause-specific mortality

BACKGROUND

ETS-related gene (ERG) protein is present in 40-70% of prostate cancer and is correlated with TMPRSS2-ERG gene rearrangements. This study evaluated ERG expression at radical prostatectomy to determine whether it was predictive of earlier relapse or prostate cancer-specific mortality (PCSM).

METHODS

One hundred patients who underwent radical prostatectomy at Virginia Mason in Seattle between 1991 and 1997 were identified. Recurrence was confirmed by tissue diagnosis or radiographic signs. PCSM was confirmed by death certificates. Thirty-three patients with metastases or PCSM were matched to patients without recurrence at a 1:2 ratio. Paraffin embedded tissue was stained with two anti-ERG monoclonal antibodies, EPR3864 and 9FY. Nuclear expression intensity was evaluated as present/absent, on a 4-point relative intensity scale, and as a composite score (0-300).

RESULTS

Mean follow-up was 10.26 years. The two antibodies were highly correlated (P < 0.0001). Patients with higher ERG expression intensity and composite scores were significantly more likely to develop biochemical relapse, metastases, and PCSM. Kaplan-Meier survival curve analysis for the composite score of ERG expression revealed a significant association between higher ERG expression (EPR3864) and shorter PCa-specific survival (P = 0.047).

CONCLUSIONS

While the presence of ERG expression at the time of surgery was not predictive of earlier relapse or PCSM, the relative intensity and composite score for ERG expression was prognostic for the development of biochemical relapse, metastases, and PCSM. Quantitative ERG scoring may be useful to identify patients who would benefit from adjuvant treatment or closer follow-up, allowing more accurate individual patient treatment plans.

Acceptance and use of eight arsenic-safe drinking water options in Bangladesh

Arsenic contamination of drinking water is a serious public health threat. In Bangladesh, eight major safe water options provide an alternative to contaminated shallow tubewells: piped water supply, deep tubewells, pond sand filters, community arsenic-removal, household arsenic removal, dug wells, well-sharing, and rainwater harvesting. However, it is uncertain how well these options are accepted and used by the at-risk population. Based on the RANAS model (risk, attitudes, norms, ability, and self-regulation) this study aimed to identify the acceptance and use of available safe water options. Cross-sectional face-to-face interviews were used to survey 1,268 households in Bangladesh in November 2009 (n = 872), and December 2010 (n = 396). The questionnaire assessed water consumption, acceptance factors from the RANAS model, and socioeconomic factors. Although all respondents had access to at least one arsenic-safe drinking water option, only 62.1% of participants were currently using these alternatives. The most regularly used options were household arsenic removal filters (92.9%) and piped water supply (85.6%). However, the former result may be positively biased due to high refusal rates of household filter owners. The least used option was household rainwater harvesting (36.6%). Those who reported not using an arsenic-safe source differed in terms of numerous acceptance factors from those who reported using arsenic-safe sources: non-users were characterized by greater vulnerability; showed less preference for the taste and temperature of alternative sources; found collecting safe water quite time-consuming; had lower levels of social norms, self-efficacy, and coping planning; and demonstrated lower levels of commitment to collecting safe water. Acceptance was particularly high for piped water supplies and deep tubewells, whereas dug wells and well-sharing were the least accepted sources. Intervention strategies were derived from the results in order to increase the acceptance and use of each arsenic-safe water option.

International multicentre study examining selection criteria for active surveillance in men undergoing radical prostatectomy

Background:

The controversies concerning possible overtreatment of prostate cancer, highlighted by debate over PSA screening, have highlighted active surveillance (AS) as an alternative management option for appropriate men. Regional differences in the underlying prevalence of PSA testing may alter the pre-test probability for high-risk disease, which can potentially interfere with the performance of selection criteria for AS. In a multicentre study from three different countries, we examine men who were initially suitable for AS according to the Toronto and Prostate Cancer Research International: Active Surveillance (PRIAS) criteria, that underwent radical prostatectomy (RP) in regards to:1.the proportion of pathological reclassification(Gleason score ⩾7, ⩾pT3 disease),2.predictors of high-risk disease,3.create a predictive model to assist with selection of men suitable for AS.

Methods:

From three centres in the United Kingdom, Canada and Australia, data on men who underwent RP were retrospectively reviewed (n=2329). Multivariable logistic regression was performed to identify predictors of high-risk disease. A nomogram was generated by logistic regression analysis, and performance characterised by receiver operating characteristic curves.

Results:

For men suitable for AS according to the Toronto (n=800) and PRIAS (410) criteria, the rates for upgrading were 50.6, 42.7%, and upstaging 17.6, 12.4%, respectively. Significant predictors of high-risk disease were:•Toronto criteria: increasing age, cT2 disease, centre of diagnosis and number of positive cores.•PRIAS criteria: increasing PSA and cT2 disease.Cambridge had a high pT3a rate (26 vs 12%). To assist selection of men in the United Kingdom for AS, from the Cambridge data, we generated a nomogram predicting high-risk features in patients who meet the Toronto criteria (AUC of 0.72).

Conclusion:

The proportion of pathological reclassification in our cohort was higher than previously reported. Care must be used when applying the AS criteria generated from one population to another. With more stringent selection criteria, there is less reclassification but also fewer men who may benefit from AS.

Arsenic in tube well water in Bangladesh: health and economic impacts and implications for arsenic mitigation

A national drinking water quality survey conducted in 2009 furnished data that were used to make an updated estimate of chronic arsenic exposure in Bangladesh. About 20 million and 45 million people were found to be exposed to concentrations above the national standard of 50 µg/L and the World Health Organization's guideline value of 10 µg/L, respectively. From the updated exposure data and all-cause mortality hazard ratios based on local epidemiological studies, it was estimated that arsenic exposures to concentrations > 50 µg/L and 10-50 µg/L account for an annual 24,000 and perhaps as many as 19,000 adult deaths in the country, respectively. Exposure varies widely in the 64 districts; among adults, arsenic-related deaths account for 0-15% of all deaths. An arsenic-related mortality rate of 1 in every 16 adult deaths could represent an economic burden of 13 billion United States dollars (US$) in lost productivity alone over the next 20 years. Arsenic mitigation should follow a two-tiered approach: (i) prioritizing provision of safe water to an estimated 5 million people exposed to > 200 µg/L arsenic, and (ii) building local arsenic testing capacity. The effectiveness of such an approach was demonstrated during the United Nations Children's Fund 2006-2011 country programme, which provided safe water to arsenic-contaminated areas at a cost of US$ 11 per capita. National scale-up of such an approach would cost a few hundred million US dollars but would improve the health and productivity of the population, especially in future generations.

Using child health outcomes to identify effective measures of handwashing

We assessed which practical handwashing indicators were independently associated with reduced child diarrhea or respiratory disease. Fieldworkers collected 33 indicators of handwashing at baseline in 498 households in 50 villages in rural Bangladesh. Community monitors visited households monthly and asked standard questions about diarrhea and symptoms of respiratory illness among children under 5 years of age. In multivariate analysis, three handwashing indicators were independently associated with less child diarrhea-mothers reporting usually washing hands with soap before feeding a child, mothers using soap when asked to show how they usually washed their hands after defecation, and children having visibly clean finger pads. Two indicators were independently associated with fewer respiratory infections-mothers allowing their hands to air dry after the handwashing demonstration and the presence of water where the respondents usually wash hands after defecation. These rapid handwashing indicators should be considered for inclusion in handwashing assessments.

Interim evaluation of a large scale sanitation, hygiene and water improvement programme on childhood diarrhea and respiratory disease in rural Bangladesh

Started in 2007, the Sanitation Hygiene Education and Water Supply in Bangladesh (SHEWA-B) project aims to improve the hygiene, sanitation and water supply for 20 million people in Bangladesh, and thus reduce disease among this population. This paper assesses the effectiveness of SHEWA-B on changing behaviors and reducing diarrhea and respiratory illness among children < 5 years of age. We assessed behaviors at baseline in 2007 and after 6 months and 18 months by conducting structured observation of handwashing behavior in 500 intervention and 500 control households. In addition we conducted spot checks of water and sanitation facilities in 850 intervention and 850 control households. We also collected monthly data on diarrhea and respiratory illness from 500 intervention and 500 control households from October 2007 to September 2009. Participants washed their hands with soap < 3% of the time around food related events in both intervention and control households at baseline and after 18 months. Washing both hands with soap or ash after cleaning a child's anus increased from 22% to 36%, and no access to a latrine decreased from 10% to 6.8% from baseline to 18 months. The prevalence of diarrhea and respiratory illness, among children <5 years of age were similar in intervention and control communities throughout the study. This large scale sanitation, hygiene and water improvement programme resulted in improvements in a few of its targeted behaviors, but these modest behavior changes have not yet resulted in a measurable reduction in childhood diarrhea and respiratory illness.

The effect of handwashing at recommended times with water alone and with soap on child diarrhea in rural Bangladesh: an observational study

BACKGROUND

Standard public health interventions to improve hand hygiene in communities with high levels of child mortality encourage community residents to wash their hands with soap at five separate key times, a recommendation that would require mothers living in impoverished households to typically wash hands with soap more than ten times per day. We analyzed data from households that received no intervention in a large prospective project evaluation to assess the relationship between observed handwashing behavior and subsequent diarrhea.

METHODS AND FINDINGS

Fieldworkers conducted a 5-hour structured observation and a cross-sectional survey in 347 households from 50 villages across rural Bangladesh in 2007. For the subsequent 2 years, a trained community resident visited each of the enrolled households every month and collected information on the occurrence of diarrhea in the preceding 48 hours among household residents under the age of 5 years. Compared with children living in households where persons prepared food without washing their hands, children living in households where the food preparer washed at least one hand with water only (odds ratio [OR]=0.78; 95% confidence interval [CI]=0.57-1.05), washed both hands with water only (OR=0.67; 95% CI=0.51-0.89), or washed at least one hand with soap (OR=0.30; 95% CI=0.19-0.47) had less diarrhea. In households where residents washed at least one hand with soap after defecation, children had less diarrhea (OR=0.45; 95% CI=0.26-0.77). There was no significant association between handwashing with or without soap before feeding a child, before eating, or after cleaning a child's anus who defecated and subsequent child diarrhea.

CONCLUSIONS

These observations suggest that handwashing before preparing food is a particularly important opportunity to prevent childhood diarrhea, and that handwashing with water alone can significantly reduce childhood diarrhea.

Household characteristics associated with handwashing with soap in rural Bangladesh

Handwashing with soap prevents diarrhea and respiratory disease, but it is rarely practiced in high-need settings. Among 100 randomly selected villages in rural Bangladesh, field workers enrolled 10 households per village and observed and recorded household activities for 5 hours. Field workers observed 761 handwashing opportunities among household members in 527 households who had just defecated or who cleaned a child's anus who had defecated. In the final multivariate analysis, having water available at the place to wash hands after toileting (odds ratio = 2.2, 95% confidence interval 1.3, 4.0) and having soap available at the place to wash hands after toileting (odds ratio = 2.1, 95% confidence interval 1.3, 3.4) were associated with washing both hands with soap after fecal contact. Interventions that improve the presence of water and soap at the designated place to wash hands would be expected to improve handwashing behavior and health.

Tubewell water quality and predictors of contamination in three flood-prone areas in Bangladesh

AIMS

To measure enteric bacterial contamination of tubewells in three flood prone areas in Bangladesh and the relationship of bacteriological contamination with tubewell sanitary inspection scores.

METHODS AND RESULTS

Microbiologists selected 207 tubewells in three flood prone districts, assessed physical characteristics of the tubewells and collected a single water sample from each tubewell. Tubewell water samples were contaminated with total coliforms (41%, n = 85), thermotolerant coliforms (29%, n = 60) and Escherichia coli (13%, n = 27). Among contaminated wells, the median CFU of contamination per 100 ml was 8 (interquartile range, 2-30) total coliforms, 5 (interquartile range, 2-23) thermotolerant coliforms and 6 (interquartile range, 1-30) E. coli. There was no significant association between tubewell contamination with E. coli, thermotolerant coliforms or total coliforms and a poor sanitary inspection score, though a history of inundation was associated with contamination with both E. coli and thermotolerant coliforms.

CONCLUSIONS

Tubewells in flood-prone regions of Bangladesh were commonly contaminated with low levels of faecal organisms, contamination that could not be predicted by examining the tubewell's external characteristics.

SIGNIFICANCE AND IMPACT OF THE STUDY

The forms currently used for sanitary inspection do not identify the most important causes of drinking water contamination in these communities.

Will increasing folic acid in fortified grain products further reduce neural tube defects without causing harm?: consideration of the evidence

To reduce neural tube defects (NTDs), the U.S. Food and Drug Administration (FDA) mandated that by January 1998 all enriched grain products should contain 140 microg of folic acid (FA)/100 g of flour. Groups concerned with optimal prevention of NTDs had argued that the level should be 350 microg/100 g. However, when it appeared that the debate might delay implementation of any fortification, these groups petitioned the FDA to implement fortification at the originally proposed level of 140 microg/100 g, anticipating that the FDA might consider increasing the level at a later time. Mandated FA fortification (FAF) has now been in place in the United States for 9 y. The impact of this important public health intervention on NTD rates, the possible benefit to other disease conditions, and potential harms have been evaluated. As background for a possible request that the FDA consider increasing FAF, evidence bearing on the question of whether an increase can further reduce NTD births without causing harm is reviewed here. The published data indicate that it is appropriate that the FDA conduct or commission a balanced analysis of the evidence by scientists who will act on that evidence to decide this important question.

Arsenic mitigation in Bangladesh: national screening data and case studies in three upazilas

Since 2000, nearly 5 million wells in Bangladesh have been tested for arsenic. Results of this survey are presented, and it is estimated that approximately 20% of tube wells nationwide contain arsenic above the drinking water limit of 50 parts per billion, with approximately 20 million people at risk of consuming water above this limit. Three case studies in arsenic mitigation are presented, which indicate that substantial progress has been made in raising awareness about arsenic. Substantial differences were found in tubewell surveys made in 2001 and 2005, with 17% of tubewells painted green in 2001 showing arsenic above 50 ppb in 2005, and 12% of tubewells painted red in 2001 showing 50 ppb arsenic or less in 2005. In 38% of households having red tubewells, household water was found to contain 50 ppb arsenic or less, indicating substantial behaviour change. In two upazilas where safe alternatives (primarily safe shallow tubewells and newly installed deep tubewells) are available, 52% and 75% of people at risk were found to have arsenic-safe water in the household, indicating that they have changed their drinking water sources. In a third upazila where safe alternatives are scarce, less than 10% of people at risk were found to have safe water in the home. The greatest challenges remain in areas where contamination is high but installation of new safe water points is constrained for technical reasons (e.g. unsuitability of the deep aquifer).

Household pasteurization of drinking-water: the chulli water-treatment system

A simple flow-through system has been developed which makes use of wasted heat generated in traditional clay ovens (chullis) to pasteurize surface water. A hollow aluminium coil is built into the clay chulli, and water is passed through the coil during normal cooking events. By adjusting the flow rate, effluent temperature can be maintained at approximately 70 degrees C. Laboratory testing, along with over 400 field tests on chulli systems deployed in six pilot villages, showed that the treatment completely inactivated thermotolerant coliforms. The chulli system produces up to 90 litres per day of treated water at the household level, without any additional time or fuel requirement. The technology has been developed to provide a safe alternative source of drinking-water in arsenic-contaminated areas, but can also have wide application wherever people consume microbiologically-contaminated water.

A history of pediatric immunology

Immunology has played a prominent role in the history of medicine. Pediatric immunologists have focused on immune aberrations in pediatric disorders, particularly those involving host defense mechanisms. These efforts have paid rich dividends in terms of fundamental knowledge of the immune system and major therapeutic advances, including 1) i.v. immunoglobulin therapy, 2) hematopoietic stem cell transplantation, and 3) gene therapy. Pediatric immunology as an organized discipline emerged in the early 1950s, when pediatricians and their basic scientist colleagues began to focus on clinical and basic research related to immunodeficiency. Since then, key organizations and infrastructure have been developed to support this research and the clinical care of immunodeficient patients. We review here the evolution of contemporary pediatric immunology, particularly in North America, from its roots in 19th-century Europe to its current expression as one of the fundamental scientific and clinical disciplines of pediatrics.

Balancing benefits and harms in public health prevention programmes mandated by governments

Even when scientific evidence for a preventive health intervention is strong, many barriers exist to population-wide implementation

Do vaccines cause harm? The need for open-minded analysis based on science and reason

Public concern about the safety of vaccines began when vaccination began, in the 18th century. Major resistance to vaccinations in the 1980s threatened to shut down vaccine manufacture and immunization programs. The US Congress responded with legislation in 1986-1987 that established a compensation program, communication strategies, and a process of objective, science-based analysis by the Institute of Medicine of whether childhood vaccines cause any of an array of possible adverse events. Since then, research, detection, communication, and education related to vaccine safety have improved but remain less than perfect. All of us who care about children, our own or in the abstract, will serve our children best if we remain vigilant and open-minded in considering issues of vaccine safety, and if we base our conclusions and actions on science, not emotion.

Clinical aspects of chronic granulomatous disease

Data from a registry of 368 patients with chronic granulomatous disease (CGD) documenta shift in the most common infecting organisms away from staphylococci and enteric bacteria to Aspergillus species, although staphylococci remain a threat. A. nidulans appears to have a particular virulence in CGD. Burkholderia cepacia sepsis/pneumonia was the second most lethal infection in patients in the registry. Seventy-six percent of registry patients had the X-linked recessive (XLR) form of CGD. Chorioretinitis may be more common than previously appreciated, and boys with the XLR disease should probably have routine full eye exams. A new variant of CGD has been described that is caused by an inhibitory mutation in Rac2, which regulates activity of the neutrophil respiratory burst and actin assembly. Interferon-gamma, antibacterial prophylaxis, and, probably, antifungal prophylaxis with itraconazole reduce the rate of infection, and bone marrow transplantation can cure the disease if a histocompatible donor is available. Gene therapy can cure CGD in knockout mouse models. Having even a small percentage of phagocytes that are nicotinamide adenine dinucleotide phospate oxidase-positive can reduce the risk of serious infection, and procedures now under study appear close to achieving that goal, if not a cure.

The phagocytosis-associated respiratory burst in human monocytes is associated with increased uptake of glutathione

During the phagocytic respiratory burst, oxygen is converted to potent cytotoxic oxidants. Monocytes and macrophages are potentially long-lived, and we have hypothesized that protective mechanisms against oxidant stress are varied and fully expressed in these cells. We report here that the respiratory burst in monocytes is accompanied by an increase in the uptake of [35S]glutathione ([35S]GSH) after 20-30 min to levels up to 10-fold greater than those at baseline. By 30 min, 49% of the cell-associated radioactivity was in the cytosol, 41% was in membrane, and 10% was associated with the nuclear fraction. GSH uptake was inhibited by catalase, which removes hydrogen peroxide (H2O2), and micromolar H2O2 stimulated GSH uptake effectively in monocytes and also lymphocytes. Oxidation of GSH to glutathione disulfide with H2O2 and glutathione peroxidase prevented uptake. Acivicin, which inhibits GSH breakdown by gamma-glutamyl transpeptidase (GGT), had no effect on the enhanced uptake seen during the respiratory burst. Uptake of cysteine or cystine, possible products of GGT activity, stayed the same or decreased during the respiratory burst. These results suggest that a GGT-independent mechanism is responsible for the enhanced GSH uptake seen during the respiratory burst. We describe here a sodium-independent, methionine-inhibitable transport system with a Km (8.5 microM) for GSH approximating the plasma GSH concentration. These results suggest that monocytes have a specific GSH transporter that is triggered by the release of H2O2 during the respiratory burst and that induces the uptake of GSH into the cell. Such a mechanism has the potential to protect the phagocyte against oxidant damage.

Chronic granulomatous disease. Report on a national registry of 368 patients

A registry of United States residents with chronic granulomatous disease (CGD) was established in 1993 in order to estimate the minimum incidence of this uncommon primary immunodeficiency disease and characterize its epidemiologic and clinical features. To date, 368 patients have been registered; 259 have the X-linked recessive form of CGD, 81 have 1 of the autosomal recessive forms, and in 28 the mode of inheritance is unknown. The minimum estimate of birth rate is between 1/200,000 and 1/250,000 live births for the period 1980-1989. Pneumonia was the most prevalent infection (79% of patients; Aspergillus most prevalent cause), followed by suppurative adenitis (53% of patients; Staphylococcus most prevalent cause), subcutaneous abscess (42% of patients; Staphylococcus most prevalent cause), liver abscess (27% of patients; Staphylococcus most prevalent cause), osteomyelitis (25% of patients; Serratia most prevalent cause), and sepsis (18% of patients; Salmonella most prevalent cause). Fifteen percent of patients had gastric outlet obstruction, 10% urinary tract obstruction, and 17% colitis/enteritis. Ten percent of X-linked recessive kindreds and 3% of autosomal recessive kindreds had family members with lupus. Eighteen percent of patients either were deceased when registered or died after being registered. The most common causes of death were pneumonia and/or sepsis due to Aspergillus (23 patients) or Burkholderia cepacia (12 patients). Patients with the X-linked recessive form of the disease appear to have a more serious clinical phenotype than patients with the autosomal recessive forms of the disease, based on the fact that they are diagnosed significantly earlier (mean, 3.01 years of age versus 7.81 years of age, respectively), have a significantly higher prevalence of perirectal abscess (17% versus 7%), suppurative adenitis (59% versus 32%), bacteremia/fungemia (21% versus 10%), gastric obstruction (19% versus 5%), and urinary tract obstruction (11% versus 3%), and a higher mortality (21.2% versus 8.6%).

Preclinical evaluation of a rheolytic catheter for percutaneous coronary artery/saphenous vein graft thrombectomy

The presence of thrombus increases the rate of acute complications and restenosis in percutaneous revascularization of native coronary arteries and saphenous vein grafts. Rheolytic thrombectomy uses high velocity saline jets to create a Bernoulli effect for thrombus entrainment, dissociation, and evacuation of debris, providing a novel approach to the treatment of thrombotic lesions. The study objective was to determine the preclinical safety and effectiveness of a 5 French rheolytic thrombectomy catheter designed for use in coronary arteries and saphenous vein grafts. In vitro testing was performed to evaluate catheter effectiveness (clot removal rate) and safety (particle generation and hemolysis). This was followed by acute (n = 6) and chronic (n = 6) canine studies to determine hemodynamic, angiographic, and histopathologic effects of the catheter. The results showed effective clot removal with minimal embolization: 99.4% of the total clot volume was removed with only 0.1% proximal embolization and 0.5% distal embolization. 98.4% of the embolic particles were less than 10 microm. Canine studies revealed no significant angiographic, hemodynamic, histopathologic, or electrocardiographic abnormalities with the exception of transient heart block in one animal. There was transient hemolysis which normalized within 24 hours with no adverse effects. These results demonstrate the effectiveness and safety of coronary rheolytic thrombectomy and provided the basis for clinical trials to further evaluate this promising new approach for coronary thrombectomy.

Effect of lower extremity muscular fatigue on motor control performance

PURPOSE

The purpose of this study was to determine whether lower extremity fatigue affects the ability of an individual to balance on an unstable platform.

METHODS

Twenty healthy subjects (average age, 29 yr, range, 20 to 39 yr) were tested on an instrumented balance assessment system. Static tests were done on the limbs unilaterally and then bilaterally, and finally a dynamic test was performed in which the subject moved the platform in a circular manner to chase a moving object on a computer screen. After testing, subjects were fatigued using an isokinetic dynamometer, which imposes closed kinetic chain antagonistic exercise on the ankle, knee, and hip, similar to a stair stepper. No rest was allowed, and subjects were fatigued to less than 50% of their initial tested force. Subjects were then immediately retested on the unstable platform using the same testing protocol. All subjects completed the testing.

RESULTS

Analysis of pre- and post-fatigue balance results demonstrated significant decreases in motor control performance on the three static tests following exercise to fatigue in all subjects (P < 0.001).

CONCLUSIONS

Our findings support anecdotal evidence that fatigued individuals are at increased risk of injury because of loss of balance. Avoidance of fatigue and preconditioning may prevent injury.

Augmentation of human macrophage candidacidal capacity by recombinant human myeloperoxidase and granulocyte-macrophage colony-stimulating factor

Phagocyte myeloperoxidase (MPO) is believed to be particularly important in defense against candida infection. We reported earlier that monocytes, rich in MPO, killed Candida albicans at a significantly higher rate and extent than did monocyte-derived macrophages, known to lack MPO, and that C. albicans is less resistant to MPO-dependent oxidants than less pathogenic Candida species. We hypothesized, therefore, that the capacity of macrophages to kill C. albicans might be improved in the presence of MPO. In this study, we evaluated the ability of recombinant human MPO (rhMPO) to augment the killing of C. albicans by resident macrophages and macrophages activated by recombinant human granulocyte-macrophage colony-stimulating factor. Addition of rhMPO (concentration range, 0.8 to 6.4 U/ml) to suspensions of resident and activated macrophages and opsonized C. albicans resulted in concentration-dependent and significant increases in candida killing. This enhancement was particularly pronounced with activated macrophages, whether C. albicans was opsonized or unopsonized and ingested through the macrophage mannose receptor. rhMPO did not affect the killing of C. albicans by monocytes, nor did it affect phagocytosis of opsonized or unopsonized C. albicans. These results indicate that exogenous rhMPO can augment the candidacidal capacity of both resident and activated macrophages, with a more profound effect on activated cells. We suggest that rhMPO may be effective in the treatment of invasive candidiasis.

The effect of using "race of child" instead of "race of mother" on the black-white gap in infant mortality due to birth defects

OBJECTIVE

For at least 20 years, birth defects have been the leading cause of infant mortality in the United States. Some studies have reported higher rates for black infants than white infants of mortality due to birth defects, while other studies have reported no black-white differences. The authors analyzed the effect on these rates of a change in the way the National Center for Health Statistics (NCHS) tabulates "race" for newborns.

METHODS

The authors calculated infant mortality rates due to birth defects for 1980-1993 using two standard methods of assigning newborns to "racial" categories: a "race of child" algorithm and the "race of mother" approach currently used by NCHS.

RESULTS

From 1980 through 1993, birth defect-specific infant mortality rates (BD-IMRs) were significantly higher for black infants than white infants 12 of the 14 years by "race of mother" and only 5 of 14 years by "race of child." Calculation of BD-IMRs by "race of mother" reduced the rate for white infants and increased the rate for black infants in each of the 14 years. The choice of method for assigning newborns to "racial" categories had a progressively greater effect over time on the black-white gap in BD-IMRs.

CONCLUSIONS

Calculations of trends in "race"-specific BD-IMRs by may vary substantially by whether "race of mother" or "race of child" is used. Identifying the method of tabulation is imperative for appropriate comparisons and interpretations.

Characterization of multiple cysteine and cystine transporters in rat alveolar type II cells

Cysteine availability is rate limiting for the synthesis of glutathione, an important antioxidant in the lung. We used rat alveolar epithelial type II cells to study the mechanism of cysteine and cystine uptake. Consistent with carrier-mediated transport, each uptake process was saturable with Michaelis-Menten kinetics and was inhibited at 4 degrees C and by micromolar levels of amino acids or analogs known to be substrates for a specific transporter. A unique system XAG was found that transports cysteine and cystine (as well as glutamate and aspartate, the only substrates previously described for system XAG). We also identified a second Na(+)-dependent cysteine transporter system, system ASC, and two Na(+)-independent transporter systems, system xc for cystine and system L for cysteine. In the presence of glutathione at levels measured in rat plasma and alveolar lining fluid, cystine was reduced to cysteine and was transported on systems ASC and XAG, doubling the transport rate. Cysteinylglycine, released from glutathione at the cell surface by gamma-glutamyl transpeptidase, also stimulated uptake after reduction of cystine. These findings suggest that, under physiological conditions, cysteine and cystine transport is influenced by the extracellular redox state.

Folic acid supplementation--when and how

The periconceptional intake of 400 micrograms of folic acid can prevent 50-70% of neural tube defects. It is difficult to achieve this intake with diet alone, even with the recently approved levels for grain-food fortification. Therefore, a daily multivitamin with folic acid is recommended for all women of childbearing potential. Obstetrician-gynecologists should exercise every opportunity to educate their patients to this end. Although raised as a concern, the potential of masking the megaloblastic anemia of pernicious anemia is unlikely with these levels of supplementation, and considering the rarity of the disease in women of reproductive age.

Diamide primes neutrophils for enhanced release of superoxide anion: relationship to S-thiolation of cellular proteins

Stimulation of the respiratory burst in phagocytes induces the formation of mixed disulfides between sulfhydryl groups of proteins and low-molecular-weight thiols. We hypothesized that this process (S-thiolation) might be involved in turning off the respiratory burst. However, induction of S-thiolation by pretreatment of neutrophils with diamide, a direct thiol oxidizing agent, actually primed the cells for a two- to fivefold increase in total release and fourfold increase in rate of release of 02- on stimulation by f-Met-Leu-Phe. Generation of intracellular oxidants (hydroethidine fluorescence) was increased ninefold. Priming and S-thiolation were apparent at 1 min of incubation and peaked at 5-10 min. Diamide pretreatment also reduced the lag time between addition of phorbol diester and release of 02- by a mean of 23 s (41%). Dithioerythritol, a sulfhydryl-reducing agent, abolished both the S-thiolation and priming mediated by diamide. H202 also induced priming and S-thiolation; and these were eliminated by dithioerythritol. In contrast to the effect of endotoxin, diamide priming did not affect Ca2+ homeostasis of the neutrophils. Diamide did not significantly alter NADPH oxidase activity in a cell-free system. These findings suggest that sulfhydryl groups on one or more proteins play an important role in modulating the respiratory burst.