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The rate of cigarette smoking is greater among persons with mental health and/or substance abuse problems. There are few population-based datasets with which to study tobacco mortality in these vulnerable groups. The Oregon Health Authority identified persons who received publicly-funded mental health or substance abuse services from January 1996 through December 2005. These cases were then matched to Oregon Vital Statistics records for all deaths (N= 148,761) in the period 1999-2005. The rate of tobacco-related death rates was higher among persons with substance abuse problems only (53.6%) and those with both substance abuse and mental health problems (46.8%), as compared to the general population (30.7%). The rate of tobacco-related deaths among persons with mental health problems (30%) was similar to that in the general population. Persons receiving substance abuse treatment alone, or receiving both substance abuse and mental health treatment, were more likely to die and more likely to die prematurely of tobacco-related causes as compared to the general population. Persons receiving mental health services alone were not more likely to die of tobacco-related causes, but tobacco-related deaths occurred earlier in this population.  相似文献   
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A series of new selective, high affinity A(1)-AdoR agonists is reported. Compound 23 that incorporated a carboxylic acid functionality in the 4-position of the pyrazole ring displayed K(iL) value of 1 nM for the A(1)-AdoR and >5000-fold selectivity over the A(3) and A(2A)-AdoRs. In addition, compound 19 that incorporated a carboxamide functionality in the 4-position of the pyrazole ring displayed subnanomolar affinity for the A(1)-AdoR (K(iL)=0.6 nM) and >600-fold selectivity over the A(3) and A(2A)-AdoRs.  相似文献   
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A major unmet clinical need is a therapeutic capable of removing hepatitis B virus (HBV) genome from the liver of infected individuals to reduce their risk of developing liver cancer. A strategy to deliver such a therapy could utilize the ability to target and promote apoptosis of infected hepatocytes. Presently there is no clinically relevant strategy that has been shown to effectively remove persistent episomal covalently closed circular HBV DNA (cccDNA) from the nucleus of hepatocytes. We used linearized single genome length HBV DNA of various genotypes to establish a cccDNA-like reservoir in immunocompetent mice and showed that clinical-stage orally administered drugs that antagonize the function of cellular inhibitor of apoptosis proteins can eliminate HBV replication and episomal HBV genome in the liver. Primary human liver organoid models were used to confirm the clinical relevance of these results. This study underscores a clinically tenable strategy for the potential elimination of chronic HBV reservoirs in patients.Subject terms: Target validation, Hepatitis B, Preclinical research, Translational research  相似文献   
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Whiteflies contain primary prokaryotic endosymbionts located within specialized host cells. This endosymbiotic association is the result of a single infection of the host followed by vertical transmission of the endosymbiont to the progeny. Whiteflies may also be associated with other bacteria called secondary (S-) endosymbionts. The nucleotide sequence of the 16S–23S ribosomal DNA from S-endosymbionts of 13 whitefly species was determined. A phylogenetic analysis of these sequences indicated their grouping into two major clusters, one consisting of two S-endosymbionts related to previously described T-type endosymbionts. The second cluster contained the 16S–23S rDNA sequence of the type strain of Arsenophonus nasoniae as well as sequences of S-endosymbionts from 11 whitefly species. This Arsenophonus cluster contained four S-endosymbionts with intervening sequences of 70–184 nucleotides in their 23S rDNAs. The phylogenetic tree of the Arsenophonus cluster differed greatly from the phylogenetic tree of the primary endosymbionts. These results suggest that, unlike the primary endosymbiont, Arsenophonus may infect whiteflies multiple times and may also be horizontally transmitted.  相似文献   
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The whitefly Bemisia tabaci contains a primary prokaryotic endosymbiont housed within specialized cells in the body cavity. Two DNA fragments from the endosymbiont, totaling 33.3 kilobases, were cloned and sequenced. In total, 37 genes were detected and included the ribosomal RNA operon and genes for ribosomal RNA proteins. The guanine plus cytosine of the DNA was 30.2 mol%, different from that of endosymbionts of other plant sap-sucking insects.  相似文献   
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Oncogenic RAS mutants such as v-Ha-RAS induce cell cycling, in particular the G1 to S transition, by upregulating cyclin D1 and downregulating p27, an inhibitor for cyclin-dependent kinases (CDKs). PI-3 kinase appears to be involved in the regulation of both cyclin D1 and p27. In this report, using two distinct inhibitors specific for PAK1-3 (CEP-1347 and WR-PAK18), we present the first evidence indicating that the PIX/Rac/CDC42-dependent Ser/Thr kinases PAK1-3, acting downstream of PI-3 kinase and upstream of the Raf/MEK/ERKs kinase cascade, is essential for RAS-induced upregulation of cyclin D1, but not downregulation of p27. Since these PAK-inhibitors block selectively the malignant growth of RAS transformants, in which PAK1 is constitutively activated, but not normal cell growth, it is suggested that RAS transformants are addicted to the high levels of PAK1 for their malignant entry to S phase.  相似文献   
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Protein arrays permit the parallel analysis of many different markers in a small sample volume. However, the problem of cross-reactivity limits the degree of multiplexing in parallel sandwich immunoassays (using monoclonal antibodies (mAbs)), meaning antibodies must be prescreened in order to reduce false positives. In contrast, we use a second chip surface for the local application of detection antibodies, thereby efficiently eliminating antibody cross-reactions. Here, we illustrate the potential advantages of using single-chain Fv fragments rather than mAbs as capture and detection molecules with this double chip technology.  相似文献   
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