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121.
Organophosphorus compounds (OPCs) are widely used in agriculture as pesticides and occasionally in industrial settings. They have also been developed as warfare nerve agents. OPCs poisoning from intentional, accidental, and occupational exposure is a major public health problem, especially across the rural developing world. The main toxic mechanism of OPCs is the inhibition of the enzymes acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), resulting in accumulation of acetylcholine (ACh) at the synapse with cholinergic crisis and possible death. Exposure to even small amounts of an OPC can be fatal and death is usually caused by respiratory failure. Standard treatment involves the administration of intravenous atropine and an oxime to counteract acetylcholinesterase inhibition at the synapse, but the usefulness of oximes is still debated. During more than five decades, pyridinium oximes have been developed as therapeutic agents used in the medical treatment of poisoning with OPCs. They act by reactivation of AChE inhibited by OPCs. However, their activity in poisonings with pesticides and warfare nerve agents is different, and there is still no universal oxime sufficiently effective against all known OPCs. The aim of this article was to review the most recent findings in this field and compare the protection conferred by the new K-oximes and sugar oximes with the effect of the four recommended pyridinium oximes (pralidoxime, obidoxime, trimedoxime, and HI-6), in the search for a broad-spectrum AChE reactivator. 相似文献
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Dieguez-Gonzalez R Akar S Calaza M Perez-Pampin E Costas J Torres M Vicario JL Velloso ML Navarro F Narvaez J Joven B Herrero-Beaumont G Gonzalez-Alvaro I Fernandez-Gutierrez B de la Serna AR Carreño L Lopez-Longo J Caliz R Collado-Escobar MD Blanco FJ Fernandez-Lopez C Balsa A Pascual-Salcedo D Gomez-Reino JJ Gonzalez A 《Annals of the rheumatic diseases》2009,68(4):579-583
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Pinaud R Terleph TA Tremere LA Phan ML Dagostin AA Leão RM Mello CV Vicario DS 《Journal of neurophysiology》2008,100(1):441-455
The role of GABA in the central processing of complex auditory signals is not fully understood. We have studied the involvement of GABA A-mediated inhibition in the processing of birdsong, a learned vocal communication signal requiring intact hearing for its development and maintenance. We focused on caudomedial nidopallium (NCM), an area analogous to parts of the mammalian auditory cortex with selective responses to birdsong. We present evidence that GABA A-mediated inhibition plays a pronounced role in NCM's auditory processing of birdsong. Using immunocytochemistry, we show that approximately half of NCM's neurons are GABAergic. Whole cell patch-clamp recordings in a slice preparation demonstrate that, at rest, spontaneously active GABAergic synapses inhibit excitatory inputs onto NCM neurons via GABA A receptors. Multi-electrode electrophysiological recordings in awake birds show that local blockade of GABA A-mediated inhibition in NCM markedly affects the temporal pattern of song-evoked responses in NCM without modifications in frequency tuning. Surprisingly, this blockade increases the phasic and largely suppresses the tonic response component, reflecting dynamic relationships of inhibitory networks that could include disinhibition. Thus processing of learned natural communication sounds in songbirds, and possibly other vocal learners, may depend on complex interactions of inhibitory networks. 相似文献
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LN Barlow-Mosha DS Bagenda PK Mudiope MC Mubiru LM Butler MG Fowler PM Musoke 《African health sciences》2012,12(3):249-258
Background
Access to pediatric antiretroviral formulations is increasing in resource-limited countries, however adult FDCs are still commonly used by antiretroviral therapy (ART) programs.Objective
To describe long-term effectiveness of using adult FDC of d4T+3TC+NVP (Triomune) in children for HIV treatment.Methods
Clinical, immunologic, and virologic outcomes of HIV-infected ART-naïve children aged six months to 12 years, were evaluated up to 96 weeks post-ART initiation.Results
From March 2004 to June 2006, 104 children were followed with a median age of 5.4 years, median CD4 cell percent and HIV-1 RNA were 11.0% (IQR 6.7–13.9) and 348,846copies/mL (IQR 160,941–681,313) respectively at baseline. Using Kaplan-Meir estimates, 75% of children had undetectable viral loads (<400copies/mL) at 96weeks of ART. Children with a baseline CD4 cell percent >15% were 3 times more likely to achieve viral load <400copies/mL than those with baseline CD4 cell percent <5% after adjusting for baseline age {aHR = 3.03 (1.10–8.32), p=0.03}; no difference was found among those with CD4 cell percent >5–14.9% and <5%.Conclusion
Treatment with generic adult FDC for HIV-infected Ugandan children led to sustained clinical, immunologic and virologic response during 96 weeks of ART. Early initiation of ART is key to achieving virological success. 相似文献129.
To determine the complete sequence of a newly identified human leukocyte antigen (HLA)-C allele, we designed a method where the full genomic sequence of HLA-C*04 was amplified in isolation from the patient second HLA-C allele in a single polymerase chain reaction (PCR), using primers spanning its 5'- and 3'-untranslated regions. The new allele, officially designated HLA-C*04:71, differs from HLA-C*04:01:01:01 by two single-nucleotide polymorphisms: one determines substitution of phenylalanine for serine 9 at the B pocket of the peptide-binding site; the second substitution is a new polymorphism in intron 5. Phe-9 is characteristic of Cw1 alleles and its presence in C*04:71 most likely affects its peptide-binding repertoire. The principle we have used for C*04:71 isolation could be adapted for unambiguous sequence-based HLA-C typing of selected samples in a clinical setting. 相似文献
130.