1,166 research outputs found

    Impact of meteorological variables on water quality parameters of a reservoir and ecological filtration system

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    Recently, special attention has been given to low-cost technologies for water treatment, with the aim of serving remote communities and thus enabling everyone to have access to drinking water and basic sanitation. In that context, the ecological filter is an alternative for treating water for human consumption. Some studies show that climate change and meteorological parameters can influence the water quality of water bodies and the water supply system. However, most of the papers deal with model projections and therefore do not show real situations. The aim of this study was to determine the impact of meteorological variables (e.g. atmospheric pressure, evaporation, wind speed, radiation, precipitation) on the physico-chemical and biological parameters (e.g. turbidity, apparent colour, pH, total coliforms, Escherichia coli) of Lobo reservoir water treated by 22 ecological filters during a period of 4 months. Statistically significant correlations were found between the water from the Lobo reservoir and the weather variables, and between the water quality parameters of the 22 ecological filters and the average weather variables. The results from the statistical analysis indicate that climatic variations may influence treatment performance

    Influence of PPCPs on the performance of intermittently operated slow sand filters for household water purification

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    Removal of pharmaceuticals and personal care products (PPCPs) from drinking water is usually enhanced by advanced oxidation which is not affordable in low income countries. Slow sand filtration has been found to be capable of removing anti-inflammatory compounds, and its low maintenance costs and easy operation make it an attractive technology for treating drinking water in many parts of the world. In addition, slow sand filters can be used at both large and household scales. The biofilm (i.e. schmutzdecke) developed on the top of the sand and within the upper layers of the sand is acknowledged to be responsible for the water purification. However, it is possible that the PPCPs may affect the schmutzdecke development and microbial community within the filters, and consequently the performance of the filter. This study investigated two household slow sand filters (for water purification) operated intermittently with and without contamination by six PPCPs. Eleven parameters were monitored in the affluent and effluent water, including bacterial species present and schmutzdecke biomass development. Results demonstrated that the household slow sand filter performance was not affected by the 2μgL(-1) of PPCPs in the water. There was no significant difference between filters for total coliforms and E. coli removal, but there was considerable difference between sampling times. Biomass considerably increased with the number of filtrations in both filters and there was no significant difference between filter biomass. However, it was found that more bacterial species were present in the period with no contamination than during the contamination period. Bacillus anthracis and Exiguobacterium sp. showed to be resistant to the effects of the PPCPs. These suggest there are effects of PPCPs on bacterial species within the filter. However, the effect of the PPCPs on biomass was not conclusive in this study and needs to be further investigated

    Expression of histone methyltransferases as novel biomarkers for renal cell tumor diagnosis and prognostication

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    Renal cell tumors (RCTs) are the most lethal of the common urological cancers. The widespread use of imaging entailed an increased detection of small renal masses, emphasizing the need for accurate distinction between benign and malignant RCTs, which is critical for adequate therapeutic management. Histone methylation has been implicated in renal tumorigenesis, but its potential clinical value as RCT biomarker remains mostly unexplored. Hence, the main goal of this study was to identify differentially expressed histone methyltransferases (HMTs) and histone demethylases (HDMs) that might prove useful for RCT diagnosis and prognostication, emphasizing the discrimination between oncocytoma (a benign tumor) and renal cell carcinoma (RCC), especially the chromophobe subtype (chRCC). We found that the expression levels of three genes-SMYD2, SETD3, and NO66-was significantly altered in a set of RCTs, which was further validated in a large independent cohort. Higher expression levels were found in RCTs compared to normal renal tissues (RNTs) and in chRCCs comparatively to oncocytomas. SMYD2 and SETD3 mRNA levels correlated with protein expression assessed by immunohistochemistry. SMYD2 transcript levels discriminated RCTs from RNT, with 82.1% sensitivity and 100% specificity (AUC=0.959), and distinguished chRCCs from oncocytomas, with 71.0% sensitivity and 73.3% specificity (AUC: 0.784). Low expression levels of SMYD2, SETD3, and NO66 were significantly associated with shorter disease-specific and disease-free survival, especially in patients with non-organ confined tumors. We conclude that expression of selected HMTs and HDMs might constitute novel biomarkers to assist in RCT diagnosis and assessment of tumor aggressiveness.This study was funded by research grants from Research Center of Portuguese Oncology Institute – Porto (CI-IPOP 4-2012) and European Community’s Seventh Framework Program – Grant number FP7-HEALTH-F5-2009-241783. ASP-L and FQV are and were supported by FCT-Fundação para a Ciência e a Tecnologia grants (SFRH/SINTD/94217/2013 and SFRH/ BD/70564/2010, respectively)

    Differential effects of antigens from L. braziliensis isolates from disseminated and cutaneous leishmaniasis on in vitro cytokine production

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    BACKGROUND: Disseminated leishmaniasis is an emerging infectious disease, mostly due to L. braziliensis, which has clinical and histopathological features distinct from cutaneous leishmaniasis. METHODS: In the current study we evaluated the in vitro production of the cytokines IFN-γ, TNF-α, IL-5 and IL-10 by peripheral blood mononuclear cells (PBMC) from 15 disseminated leishmaniasis and 24 cutaneous leishmaniasis patients upon stimulation with L. braziliensis antigens genotyped as disseminated leishmaniasis or cutaneous leishmaniasis isolates. RESULTS: Regardless of the source of L. braziliensis antigens, PBMC from cutaneous leishmaniasis patients produced significantly higher IFN-γ than PBMC from disseminated leishmaniasis patients. Levels of TNF-α by PBMC from cutaneous leishmaniasis patients were significantly higher than disseminated leishmaniasis patients only when stimulated by genotyped cutaneous leishmaniasis antigens. The levels of IL-5 and IL-10 production by PBMC were very low and similar in PBMCs from both disseminated leishmaniasis and cutaneous leishmaniasis patients. The immune response of each patient evaluated by the two L. braziliensis antigens was assessed in a paired analysis in which we showed that L. braziliensis genotyped as disseminated leishmaniasis isolate was more potent than L. braziliensis genotyped as cutaneous leishmaniasis isolate in triggering IFN-γ and TNF-α production in both diseases and IL-5 only in cutaneous leishmaniasis patients. CONCLUSION: This study provides evidence that antigens prepared from genotypically distinct strains of L. braziliensis induce different degrees of immune response. It also indicates that both parasite and host play a role in the outcome of L. braziliensis infection

    Plasma glucose regulation and insulin secretion in hypertriglyceridemic mice

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    In this study, we examined glucose homeostasis and insulin secretion in transgenic mice overexpressing the human apolipoprotein CIII gene (apo CIII tg). These mice have elevated plasma levels of triglycerides, FFA and cholesterol compared to control mice. The body weight, plasma glucose, and insulin levels, glucose disappearance rates, areas under the ipGTT curve for adult (4-8 mo. old) and aged (20-24 mo. old) apo CIII tg mice and the determination of insulin during the ipGTT were riot different from those of control mice. However, an additional elevation of plasma FFA by treatment with heparin for 2-4h impaired the ipGTT responses in apo CIII tg mice compared to saline-treated mice. The glucose disappearance rate in heparin-treated transgenic mice was slightly lower than in heparin-treated controls. Glucose (22.2 mmol/l) stimulated insulin secretion in isolated islets to the same extent in saline-treated control and apo CIII tg mice. in islets from heparin-treated apo CIII tg mice, the insulin secretion at 2.8 and 22.2 mmol glucose/l was lower than in heparin-treated control mice. In conclusion, hypertriglyceridemia per se or a mild elevation in FFA did not affect insulin secretion or insulin resistance in adult or aged apo CIII tg mice. Nonetheless, an additional elevation of FFA induced by heparin in hypertriglyceridemic mice impaired the ipGTT by reducing insulin secretion.341212
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