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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. © 1995 Wiley-Liss, Inc.  相似文献   
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The title Community Health Advocate (CHA) is one of thirty or more titles used throughout the world for an indigenous outreach worker who is trusted and respected in his or her community and who serves as a bridge between peers and health professionals. In 1992, the Center for Healthy Communities in Dayton, Ohio developed a program to train as Advocates people indigenous to the communities in which they would be working. Since the first CHAs began work in January 1993, the effectiveness of the program has been evaluated from three perspectives: the Community Health Advocates, the managers directors of the community sites at which the CHAs work, and the clients with whom the CHAs work. Advocates indicated that the training program adequately prepared them for their roles and functions. They also identified systematic frustrations and barriers that made it more difficult for them to perform their job. Community site directors and community leaders indicated that the CHAs were considered a positive force in meeting client needs and facilitating independence, and were very effective in outreach and coordination of resources. A survey of CHA clients revealed an overwhelmingly positive response to the Advocate's work, validating the belief that CHAs can fill an important niche in the health care community. The three evaluation processes described in this paper helped to document the need for and the effectiveness of this program and can serve as a model for similar programs.  相似文献   
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RNA interference is a powerful tool for studying gene function and for drug target discovery in diverse organisms and cell types. In mammalian systems, small interfering RNAs (siRNAs), or DNA plasmids expressing these siRNAs, have been used to down-modulate gene expression. However, inefficient transfection protocols, in particular, for primary cell types, have hampered the use of these tools in disease-relevant cellular assays. To be able to use this technology for genome-wide function screening, a more robust transduction protocol, resulting in a longer duration of the knock-down effect, is required. Here, we describe the validation of adenoviral vectors that express hairpin RNAs that are further processed to siRNAs. Infection of cell lines, or primary human cells, with these viruses leads to an efficient, sequence-specific, and prolonged reduction of the corresponding target mRNA, resulting in a reduction of the encoded protein level in the cell. For knock-down of one of the targets, GalphaS, we have measured inhibition of ligand-dependent, G-protein-coupled signaling. It is expected that this technology will prove to be of great value in target validation and target discovery efforts.  相似文献   
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Congenital nephrogenic diabetes insipidus (NDI) is a rare disease caused most often by mutations in the vasopressin V2 receptor (AVPR2). We studied a family which included a female patient with NDI with symptoms dating from infancy. The patient responded to large doses of desmopressin (dDAVP) which decreased urine volume from 10 to 4 I/day. Neither the parents nor the three sisters were polyuric. The patient was found to be a compound heterozygote for two novel recessive point mutations in the aquaporin-2 (AQP2) gene: L22V in exon 1 and C181W in exon 3. Residue Cys181 in AQP2 is the site for inhibition of water permeation by mercurial compounds and is located near to the NPA motif conserved in all aquaporins. Osmotic water permeability (Pf) in Xenopus oocytes injected with cRNA encoding C181W-AQP2 was not increased over water control, while expression of L22V cRNA increased the Pf to approximately 60% of that for wild-type AQP2. Co-injection of the mutant cRNAs with the wild-type cRNA did not affect the function of the wild-type AQP2. Immunolocalization of AQP2-transfected CHO cells showed that the C181W mutant had an endoplasmic reticulum-like intracellular distribution, whereas L22V and wild-type AQP2 showed endosome and plasma membrane staining. Water permeability assays showed a high Pf in cells expressing wild-type and L22V AQP2. This study indicates that AQP2 mutations can confer partially responsive NDI.   相似文献   
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Post‐transplant infections in allogeneic haematopoietic cell transplant (allo‐HCT) recipients often have severe consequences. This is especially the case when dealing with zygomycete infections where the result is often fatal. A major problem when dealing with zygomycete infections is the need for an accurate and fast diagnosis as the phylum is highly resistant towards the conventional antifungals. We herein describe a non‐fatal case of Lichtheimia corymbifera infection in an allo‐HCT recipient.  相似文献   
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Background: Supernumerary sex chromosome aneuploidies (X/Y‐aneuploidies), the presence of extra X and/or Y chromosomes, are associated with heightened rates of language impairments and social difficulties. However, no single study has examined different language domains and social functioning in the same sample of children with tri‐, tetra‐, and pentasomy X/Y‐aneuploidy. The current research sought to fill this gap in the literature and to examine dosage effects of X and Y chromosomes on language and social functioning. Methods: Participants included 110 youth with X/Y‐aneuploidies (32 female) and 52 with typical development (25 female) matched on age (mean ~12 years; range 4–22) and maternal education. Participants completed the Wechsler intelligence scales, and parents completed the Children’s Communication Checklist‐2 and the Social Responsiveness Scale to assess language skills and autistic traits, respectively. Results: Both supernumerary X and Y chromosomes were related to depressed structural and pragmatic language skills and increased autistic traits. The addition of a Y chromosome had a disproportionately greater impact on pragmatic language; the addition of one or more X chromosomes had a disproportionately greater impact on structural language. Conclusions: Given that we link extra X chromosomes with structural language impairments and an extra Y chromosome with pragmatic language impairments, X/Y‐aneuploidies may provide clues to genetic mechanisms contributing to idiopathic language impairment and autism spectrum disorders.  相似文献   
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A large and growing proportion of the global population rely on shared sanitation facilities despite evidence of a potential increased risk of adverse health outcomes compared with individual household latrines (IHLs). We sought to explore differences between households relying on shared sanitation versus IHLs in terms of demographics, sanitation facilities, and fecal exposure. We surveyed 570 households from 30 slums in Orissa, India, to obtain data on demographics, water, sanitation, and hygiene. Latrine spot-checks were conducted to collect data on indicators of use, privacy, and cleanliness. We collected samples of drinking water and hand rinses to assess fecal contamination. Households relying on shared sanitation were poorer and less educated than those accessing IHLs. Individuals in sharing households were more likely to practice open defecation. Shared facilities were less likely to be functional, less clean, and more likely to have feces and flies. No differences in fecal contamination of drinking water or hand-rinse samples were found. Important differences exist among households accessing shared facilities versus IHLs that may partly explain the apparent adverse health outcomes associated with shared sanitation. As these factors may capture differences in risk and promote sanitary improvements, they should be considered in future policy.  相似文献   
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