Exploring the relationship between sanitation and mental and social well-being: A systematic review and qualitative synthesis

The WHO defines health not as the absence of disease but as a "state of complete physical, mental, and social well-being." To date, public health research on sanitation has focused mainly on the impact of sanitation on infectious diseases and related sequelae, such as diarrhea and malnutrition. This review focuses on the mental and social well-being implications of sanitation. We systematically searched leading databases to identify eligible studies. Qualitative studies were assessed using a 17-point checklist adapted from existing tools, while quantitative studies were assessed using the Liverpool Quality Appraisal Tool. We followed a best-fit framework synthesis approach using six a priori well-being dimensions (privacy, shame, anxiety, fear, assault, and safety), which were examined using line-by-line coding. Two additional dimensions (dignity and embarrassment) inductively emerged during coding for a total of eight well-being outcomes. We then synthesized coded text for each dimension into descriptive themes using thematic analysis. For quantitative studies, we extracted any measures of association between sanitation and well-being. We identified 50 eligible studies covering a variety of populations and sanitation contexts but many studies were conducted in India (N = 14) and many examined the sanitation experience for women and girls (N = 19). Our synthesis results in a preliminary conceptual model in which privacy and safety, including assault, are root well-being dimensions. When people perceive or experience a lack of privacy or safety during open defecation or when using sanitation infrastructure, this can negatively influence their mental and social well-being. We found that perceptions and experiences of privacy and safety are influenced by contextual and individual factors, such as location of sanitation facilities and user's gender identity, respectively. Privacy and safety require thorough examination when developing sanitation interventions and policy to ensure a positive influence on the user's mental and social well-being.

Chronic treatment with angiotensin-(1-7) improves renal endothelial dysfunction in apolipoproteinE-deficient mice

BACKGROUND AND PURPOSE

ApolipoproteinE-deficient [apoE (-/-)] mice, a model of human atherosclerosis, develop endothelial dysfunction caused by decreased levels of nitric oxide (NO). The endogenous peptide, angiotensin-(1-7) [Ang-(1-7)], acting through its specific GPCR, the Mas receptor, has endothelium-dependent vasodilator properties. Here we have investigated if chronic treatment with Ang-(1-7) improved endothelial dysfunction in apoE (-/-) mice.

EXPERIMENTAL APPROACH

ApoE (-/-) mice fed on a lipid-rich Western diet were divided into three groups and treated via osmotic minipumps with either saline, Ang-(1-7) (82 µg·kg(-1) ·h(-1) ) or the same dose of Ang-(1-7) together with D-Ala-Ang-(1-7) (125 µg·kg(-1) ·h(-1) ) for 6 weeks. Renal vascular function was assessed in isolated perfused kidneys.

KEY RESULTS

Ang-(1-7)-treated apoE (-/-) mice showed improved renal endothelium-dependent vasorelaxation induced by carbachol and increased renal basal cGMP production, compared with untreated apoE (-/-) mice. Tempol, a reactive oxygen species (ROS) scavenger, improved endothelium-dependent vasorelaxation in kidneys of saline-treated apoE (-/-) mice whereas no effect was observed in Ang-(1-7)-treated mice. Chronic treatment with D-Ala-Ang-(1-7), a specific Mas receptor antagonist, abolished the beneficial effects of Ang-(1-7) on endothelium-dependent vasorelaxation. Renal endothelium-independent vasorelaxation showed no differences between treated and untreated mice. ROS production and expression levels of the NAD(P)H oxidase subunits gp91phox and p47phox were reduced in isolated preglomerular arterioles of Ang-(1-7)-treated mice, compared with untreated mice, whereas eNOS expression was increased.

CONCLUSION AND IMPLICATIONS

Chronic infusion of Ang-(1-7) improved renal endothelial function via Mas receptors, in an experimental model of human cardiovascular disease, by increasing levels of endogenous NO.

Interventions to improve water quality for preventing diarrhoea

BACKGROUND

Diarrhoeal diseases are a leading cause of mortality and morbidity, especially among young children in developing countries. While many of the infectious agents associated with diarrhoeal disease are potentially waterborne, the evidence for reducing diarrhoea in settings where it is endemic by improving the microbiological quality of drinking water has been equivocal.

OBJECTIVES

To assess the effectiveness of interventions to improve water quality for preventing diarrhoea.

SEARCH STRATEGY

We searched the Cochrane Infectious Diseases Group Specialized Register (December 2005), CENTRAL (The Cochrane Library 2005, Issue 4), MEDLINE (December 2005), EMBASE (December 2005), and LILACS (December 2005). We also handsearched relevant conference proceedings, contacted researchers and organizations working in the field, and checked references from identified studies.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials comparing interventions aimed at improving the microbiological quality of drinking water with no intervention in children and adults living in settings where diarrhoeal disease is endemic.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. We used meta-analyses to estimate pooled measures of effect, where appropriate, and investigated potential sources of heterogeneity using subgroup analyses.

MAIN RESULTS

Thirty trials (including 38 independent comparisons) covering over 53,000 participants met the inclusion criteria. Differences between the trials limited the comparability of results and pooling by meta-analysis. In general, the evidence suggests that interventions to improve the microbiological quality of drinking water are effective in preventing diarrhoea both for populations of all ages and children less than five years old. Subgroup analyses suggest that household interventions are more effective in preventing diarrhoea than interventions at the water source. Effectiveness was positively associated with compliance. Effectiveness was not conditioned on the presence of improved water supplies or sanitation in the study setting, and was not enhanced by combining the intervention to improve water quality with other common environmental interventions intended to prevent diarrhoea.

AUTHORS' CONCLUSIONS

Interventions to improve water quality are generally effective in preventing diarrhoea, and interventions to improve water quality at the household level are more effective than those at the source. Significant heterogeneity among the trials suggests that the actual level of effectiveness may depend on a variety of conditions that research to date cannot fully explain. Rigorous, blinded, multi-arm randomized controlled trials conducted over a longer duration in a variety if settings may help clarify the potential effectiveness.

Safe household water treatment and storage using ceramic drip filters: a randomised controlled trial in Bolivia

A randomised controlled field trial was conducted to evaluate the effectiveness of ceramic drip filters to improve the microbiological quality of drinking water in a low-income community in rural Bolivia. In four rounds of water sampling over five months, 100% of the samples were free of thermotolerant (faecal) coliforms (TTC) compared to an arithmetic mean TTC count of 1517, 406, 167 and 245 among control households which continued to use their customary sources of drinking water. The filter systems produced water that consistently met WHO drinking-water standards despite levels of turbidity that presented a challenge to other low-cost POU treatment methods. The filter systems also demonstrated an ability to maintain the high quality of the treated water against subsequent re-contamination in the home.

Effect of cutting the optic nerve on K+ currents in endfeet of Muller cells isolated from frog retina

Membrane currents were recorded from Muller cells isolated from normal retinas and from retinas whose ganglion cell axons had been cut in the optic nerve 30-60 days previously. The surgical procedure did not block the retinal blood supply and did not allow the axons to regenerate. The principal finding was that after severing the optic nerve there was less inward rectification in response to voltage commands. That is, the maintained inward current (I K(IN)) produced in response to a hyperpolarizing voltage command decreased leading to a decrease in the ratio I K(IN)/I K(OUT) In 98 mM [K+]O, this ratio was 2.86 +/- 0.21 (mean +/- SE; n = 24) in controls and 1.13 +/- 0.13 (n = 21) in Muller cells from denervated retinae. Barium, a blocker of the potassium inward rectifier (I (KIR)), eliminated this difference. Moreover, severing the optic nerve also decreased the resting potentials of Muller cells in 2.5 mM [K+]O from -83 +/- 7 mV to -63 +/- 9 mV. The results suggest that the voltage-dependent behavior and selectivity of K+ inward rectifying channels (K (ir)) in the endfeet depends on the integrity of the closely apposed ganglion cells.

Glutamate-activated ionic currents in cultured astrocytes from trout: evidence for the occurrence of non-N-methyl-D-aspartate receptors

Glutamate-induced currents were recorded from cultured trout astrocytes with the whole-cell variation of the patch-clamp technique. Ninety percent of the tested cells were directly depolarized by the amino acid neurotransmitter in a concentration-dependent manner. The depolarizing effect was due to an inward current that reversed near 0 mV and was accompanied by a noise increase, indicating the opening of an ion channel. Ion substitution experiments revealed that the glutamate-induced current was mainly carried by sodium ions but not chloride or calcium ions. The glutamate-induced response could be mimicked by the neuronal glutamate receptor subtype agonists kainate and quisqualate, while N-methyl-D-aspartate was without detectable effect.

In-the-ear hearing aids. A comparative investigation of the use of custom-made versus modular type aids

The present investigation was performed in order to evaluate and describe the benefit of a CITE-HA and compare its use with that of a modular type ITE-HA. Thirty-five patients at a median age of 70 (range 27-84) years, were fitted with CITE-HAs. As a reference group, we selected 37 patients at a median age of 74 (range 27-85) years, fitted with various types of modular in-the-ear-HAs. Based on an extensive questionnaire and an objective evaluation using insertion gain measurements and discrimination score in background noise, it was demonstrated that hearing disabled patients--even when elderly--benefit from in-the-ear-HAs; that the discrimination score measured with CITE-HAs was lower than that with the modular in-the-ear-HA; and that custom-made in-the-ear-HAs in general offer no major advantages when compared with the modular in-the-ear-HA types. In addition it was shown that the hearing aid amplification used by the majority of patients was considerably less than the amplification described by the POGO formula.