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Detection of enteric parasite DNA in household and bed dust samples: potential for infection transmission.
BACKGROUND: Enteric parasites are transmitted in households but few studies have sampled inside households for parasites and none have used sensitive molecular methods. METHODS: We collected bed and living room dust samples from households of children participating in a clinical trial of anthelmintic treatment in rural coastal Ecuador. Dust was examined for presence of DNA specific for 11 enteric parasites (Ascaris lumbricoides, Trichuris trichiura, Ancylostoma duodenale, Necator americanus, Strongyloides stercoralis, Toxocara canis and T. cati, Giardia lamblia, Blastocystis hominis, Cryptosporidium spp., and Entamoeba histolytica) by quantitative PCR (qPCR). RESULTS: Of the 38 households sampled, 37 had positive dust for at least one parasite and up to 8 parasites were detected in single samples. Positivity was greatest for B. hominis (79% of household samples) indicating a high level of environmental fecal contamination. Dust positivity rates for individual pathogens were: S. stercoralis (52%), A. lumbricoides (39%), G. lamblia (39%), Toxocara spp. (42%), hookworm (18%) and T. trichiura (8%). DNA for Cryptosporidium spp. and E. histolytica was not detected. Bed dust was more frequently positive than floor samples for all parasites detected. Positivity for A. lumbricoides DNA in bed (adjusted OR: 10.0, 95% CI: 2.0-50.1) but not floor dust (adjusted OR: 3.6, 95% CI: 0.3-37.9) was significantly associated with active infections in children. CONCLUSIONS: To our knowledge, this is the first use of qPCR on environmental samples to detect a wide range of enteric pathogen DNA. Our results indicate widespread contamination of households with parasite DNA and raise the possibility that beds, under conditions of overcrowding in a humid tropical setting, may be a source of transmission
Generation and characterization of the human iPSC line PBMC1-iPS4F1 from adult peripheral blood mononuclear cells
AbstractHere we describe the generation and characterization of the human induced pluripotent stem cell (iPSC) line PBMC1-iPS4F1 from peripheral blood mononuclear cells from a healthy female with Spanish background. We used heat sensitive, non-integrative Sendai viruses containing the reprogramming factors Oct3/4, Sox2, Klf4 and c-Myc, whose expression was silenced in the established iPSC line. Characterization of the PBMC1-iPS4F1 cell line included analysis of typical pluripotency-associated factors at mRNA and protein level, alkaline phosphatase enzymatic activity, and in vivo and in vitro differentiation studies
Improvements to the X-ray Spectrometer at the Aerosol Laboratory, Instituto de Física, UNAM
Due to the demands of better (accurate and precise) analytical results using X-ray Fluorescence (XRF) at the Aerosol Laboratory, Instituto de Física, UNAM, it was necessary to carry out improvements in instrumentation and analytical procedures in the x-ray spectrometer located in this facility. A new turbomolecular vacuum system was installed, which allows reaching the working pressure in a shorter time. Characteristic x-rays are registered with a Silicon Drift Detector, or SDD, (8 mm thick Be window, 140 eV at 5.9 keV resolution), working directly in a high-vacuum, permitting the detection of x-rays with energies as low as 1 keV (Na Ka) and higher counting rates than in the past. Due to the interference produced by the Rh L x-rays emitted by the tube normally used for atmospheric and food analysis with Cl K x-rays, another tube with a W anode was mounted in the spectrometer to avoid this interference, with the possibility to select operation with any of these tubes. Examples of applications in atmospheric aerosols and other samples are presented, to demonstrate the enhanced function of the spectrometer. Other future modifications are also explained
Flujo de potencia trifásico desbalanceado en sistemas de distribución con generación distribuida
En los últimos años, el número de unidades de generación distribuida integradas en las redes de distribución se ha venido incrementado. Bajo este nuevo escenario, la red de distribución deja de comportarse como una red pasiva y por lo tanto, los métodos tradicionales para flujo de carga en sistemas de distribución deben ser modificados. En este artículo se presenta un algoritmo de flujo de potencia trifásico desbalanceado con generación distribuida. El sistema IEEE de 34 barras fue usado para validar el algoritmo propuesto y para mostrar el efecto de la generación distribuida en las redes de distribución. En las pruebas realizadas se compara el impacto de la generación distribuida modelada como un nodo PV con el impacto de los reguladores de tensión
Flujo de potencia trifásico desbalanceado en sistemas de distribución con generación distribuida
En los últimos años, el número de unidades de generación distribuida integradas en las redes de distribución se ha venido incrementado. Bajo este nuevo escenario, la red de distribución deja de comportarse como una red pasiva y por lo tanto, los métodos tradicionales para flujo de carga en sistemas de distribución deben ser modificados. En este artículo se presenta un algoritmo de flujo de potencia trifásico desbalanceado con generación distribuida. El sistema IEEE de 34 barras fue usado para validar el algoritmo propuesto y para mostrar el efecto de la generación distribuida en las redes de distribución. En las pruebas realizadas se compara el impacto de la generación distribuida modelada como un nodo PV con el impacto de los reguladores de tensión
Evaluation of CdS Interfacial Layers in ZnO Nanowire/Poly(3-Hexylthiophene) Solar Cells
We prepare ZnO:poly(3-hexylthiophene) (P3HT) thin-film solar cells and ZnO nanowire:P3HT nanostructured solar cells
and evaluate the effect of adding an interfacial layer between the ZnO and P3HT as a function of the nanowire height.
We evaluate several different interlayers of CdS deposited, using two different chemical bath deposition (CBD) recipes.
The height of the nanowire array is varied from a bilayer device with no nanowires up to arrays with a height of 2 μm.
We find that achieving a conformal coating of the ZnO with the interfacial layer is critical to improve device performance
and that CBD can be used to grow conformal films on nonuniform surfaces
Sex-Biased Control of Inflammation and Metabolism by a Mitochondrial Nod-Like Receptor.
Mitochondria regulate steroid hormone synthesis, and in turn sex hormones regulate mitochondrial function for maintaining cellular homeostasis and controlling inflammation. This crosstalk can explain sex differences observed in several pathologies such as in metabolic or inflammatory disorders. Nod-like receptor X1 (NLRX1) is a mitochondria-associated innate receptor that could modulate metabolic functions and attenuates inflammatory responses. Here, we showed that in an infectious model with the human protozoan parasite, Leishmania guyanensis, NLRX1 attenuated inflammation in females but not in male mice. Analysis of infected female and male bone marrow derived macrophages showed both sex- and genotype-specific differences in both inflammatory and metabolic profiles with increased type I interferon production, mitochondrial respiration, and glycolytic rate in Nlrx1-deficient female BMDMs in comparison to wild-type cells, while no differences were observed between males. Transcriptomics of female and male BMDMs revealed an altered steroid hormone signaling in Nlrx1-deficient cells, and a "masculinization" of Nlrx1-deficient female BMDMs. Thus, our findings suggest that NLRX1 prevents uncontrolled inflammation and metabolism in females and therefore may contribute to the sex differences observed in infectious and inflammatory diseases
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