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The herpesvirus entry mediator A (HVEM/HveA) and nectin-1 (HveC/CD111) are two major receptors for herpes simplex virus (HSV). Although structurally unrelated, both receptors can independently mediate entry of wild-type (wt) HSV-1 and HSV-2 by interacting with the viral envelope glycoprotein D (gD). Laboratory strains with defined mutations in gD (e.g. rid1) do not use HVEM but use nectin-2 (HveB/CD112) for entry. The relative usage of HVEM and nectin-1 during HSV infection in vivo is not known. In the absence of a defined in vivo model, we used in vitro approaches to address this question. First, we screened HSV clinical isolates from various origins for receptor tropism and found that all used both HVEM and nectin-1. Second, we determined the numbers of surface receptors on various susceptible and resistant cell lines as well as on primary fibroblasts derived from an individual with cleft lip/palate ectodermal dysplasia (CLPED1). Although CLPED1 cells can only express a defective form of nectin-1, they allowed entry of wild type and mutant HSV strains by usage of either HVEM or nectin-2. Finally, we compared the ability of HVEM and nectin-1 to mediate entry when expressed at varying cell surface densities. Both receptors showed a direct relationship between the number of receptors and HSV susceptibility. Direct comparison of receptors suggests that nectin-1 is more efficient at promoting entry than HVEM. Overall, our data suggest that both receptors play a role during HSV infection in vivo and that both are highly efficient even at low levels of expression.  相似文献   
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Objectives: While the importance of exploring and better measuring elements of prenatal care have been noted in the public health literature, the components and timing of such services have been poorly examined for the overall pregnant population and specifically for African-Americans, who traditionally have had higher rates of low birth weight and premature delivery. This study explores the association between patient receipt of selected recommended prenatal care interventions and infant birth weight in a nationally representative sample of African-American women, while controlling for the influence of low birth weight risk indicators. Method: This is a retrospective case-control analysis using survey data of women who delivered normal birth weight, moderate low birth weight, and very low birth weight newborns in 1988. A sample of 3905 African-American women who responded to the 1988 National Maternal and Infant Health Survey is examined based on maternal recall of receipt of six clinical screening procedures and seven health-promotion recommendations. Birth weight measures were obtained from linked 1988 birth certificate data. Results: The initial results indicated that women who do not receive all of the recommended health-promotion advice are more likely to deliver very low birth weight infants than women who receive all of the advice in the content of their prenatal care, after controlling for low birth weight risks (OR = 1.28; 95% CI = 1.01, 1.7). However, when breast-feeding advice is removed from the aggregation of health-promotion advice, the significant effect of advice on very low birth weight is negated. No other significant group variations in the receipt of clinical screening procedures or health-promotion advice for women who gave birth in the remaining birth weight categories are observed. Conclusions: Nationally recommended initial clinical screening procedures and health-promotion advice in prenatal care content do not appear to be associated with a reduction in low birth weight for African-American women. More research is needed to better assess the impact of other antenatal interventions, particularly those given to women with a higher prevalence of poor birth outcomes.  相似文献   
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Entry of herpes simplex virus (HSV) 1 into cells requires the interaction of HSV gD with herpesvirus entry mediator or nectin1 receptors, and fusion with cell membrane mediated by the fusion glycoproteins gB, gH, and gL. We report that the gD ectodomain in soluble form (amino acids 1-305) was sufficient to rescue the infectivity of a gD-null HSV mutant, indicating that gD does not need to be anchored to the virion envelope to mediate entry. Entry mediated by soluble gD required, in addition to the receptor-binding sites contained within residues 1-250, a discrete downstream portion (amino acids 261-305), located proximal to the transmembrane segment in full-length gD. We named it as profusion domain. The pro-fusion domain was required for entry mediated by virion-bound gD, because its substitution with the corresponding region of CD8 failed to complement the infectivity of gD(-/+) HSV. Furthermore, a receptor-negative gD (gD(Delta6-259)) inhibited virus infectivity when coexpressed with wild-type gD; i.e., it acted as a dominant-negative gD mutant. The pro-fusion domain is proline-rich, which is characteristic of regions involved in protein-protein interactions. P291L-P292A substitutions diminished the gD capacity to complement gD(-/+) HSV infectivity. We propose that gD forms a tripartite complex with its receptor and, by way of the proline-rich pro-fusion domain, with the fusion glycoproteins, or with one of them. The tripartite complex would serve to recruit/activate the fusion glycoproteins and bring them from a fusion-inactive to a fusion-active state, such that they execute fusion of the virion envelope with cell membrane.  相似文献   
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The novel pyrazolo[3,4-d]pyrimidine compound GU285 (4-amino-6-alpha-carbamoylethylthio-1- phenylpyrazolo[3,4-d]pyrimidine, CAS 134896-40-5) was examined for its ability (1) to inhibit binding of adenosine (ADO) receptor ligands in rat brain membranes, (2) to antagonise functional responses to ADO agonists in rat right and left atria and coronary resistance vessels, and (3) to reduce the fall in heart rate and arterial blood pressure produced by the ADO A1 agonist N6-cyclopentyladenosine (CPA) in the intact, anaesthetized rat. GU285 competitively inhibited binding of the ADO A1 agonist [3H]-R-N6-phenylisopropyladenosine (R-PIA) yielding a Ki value of 11 (7-18) nmol.l-1 (geometric mean +/- 95% Cl). When assayed against the ADO A2A selective agonist [3H]-2-[p-(2-carboxyethyl)- phenethylamino]-5'-N-ethylcarboxamidoadenosine, (CGS21680), a Ki of 15 (10-24) nmol.l-1 was obtained. In spontaneously beating right atria, GU285 competitively antagonized negative chronotropic effects of R-PIA with a pA2 of 8.7 +/- 0.3 and in electrically paced left atria, GU285 competitively antagonized negative inotropic effects of R-PIA with a pA2 of 9.0 +/- 0.1. In the potassium-arrested, perfused rat heart GU285 (1 mumol.l-1) antagonized only the high sensitivity, ADO A2B mediated component of the biphasic relaxation of the coronary vasculature produced by NECA. The low sensitivity component was unchanged. GU285 (1 mumol.kg-1) antagonized the negative chronotropic and hypotensive effects of the adenosine A1 agonist CPA in anaesthetized rats, producing a 10-fold rightward shift in the dose-response relationship. These data demonstrate that in the rat, GU285 is a potent, non-selective adenosine receptor antagonist that maintains its activity in vivo.  相似文献   
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This article describes development of a quality of life measure designed to assess issues relevant to long-term cancer survivors. In-depth semi-structured interviews were conducted with 58 long-term cancer survivors to identify domains most relevant to long-term survivors ( 5 years post-diagnosis). Self-report items were developed from these interviews and administered to a second sample of 242 long-term survivors. Domains and items were selected from the item pool by a combination of factor analysis and criterion-based item selection. Five cancer-specific domains were identified (appearance concerns, financial problems, distress over recurrence, family-related distress, and benefits of cancer) along with seven generic QOL domains (negative feelings, positive feelings, cognitive problems, sexual problems, physical pain, fatigue, and social avoidance). Cronbachs was 0.72 or greater for each domain. Correlations between domain scores and criterion measures were 0.72 or higher in all but one generic domain (social avoidance), but somewhat lower on cancer-specific domains. The new multidimensional measure has good internal consistency and validity and is appropriate for comparisons between cancer and non-cancer populations, as well as long-term follow-up of cancer patients.  相似文献   
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Adenosine receptor-mediated coronary vasodilation was studied in isolated hearts from young (1-2 months) and mature (12-18 months) Wistar rats. The nonselective agonist 5'-N-ethylcarboxamidoadenosine (NECA) induced biphasic concentration-dependant dilation with similar potencies in both age groups (p < 0.05). Despite similar potencies, responses to NECA were significantly depressed by 50% with age. NECA-mediated dilation was unaltered by selective A adenosine receptor (A1AR) antagonist 1,3-dipropyl-8-cyclopentylxanthine (DPCPX, 100 nM ) or A adenosine receptor (A2AAR) antagonist 5-amino-7-(2-phenylethyl)-2-(2-furyl)-pyrazolo-[4,3-e]-1,2,4-triazolo[1,5- ]pyrimidine (SCH 58261, 100 nM ). However, the A2B adenosine receptor (A2B AR) selective antagonist alloxazine (10 microM ) significantly reduced response magnitude to NECA in both age groups. Concentration-response curves to N -2-(4-aminophenyl) ethyladenosine (APNEA) induced biphasic concentration-dependent dilation in hearts from young animals. In the presence of the three combined antagonists, 1 microM DPCPX, 100 nM SCH 58261, and 1 microM alloxazine, the response magnitude was significantly attenuated (p < 0.05). The addition of the A3 adenosine receptor (A3AR) antagonist 3-ethyl-5-benzyl-2-methyl-4-phenylethyl-6-phenyl-1,4-(+/-)-dihydropyridine-3,5-dicarboxylate (MRS1191, 100 nM ) to the combined antagonists further attenuated vasodilator responses to APNEA. The results suggest that multiple adenosine receptor subtypes mediate dilation in the rat coronary circulation. NECA mediates vasodilation via the A2BAR subtype, while dilator responses to APNEA in the presence and absence of A1, A2, and A3 ARs antagonists provide evidence for a vasodilator role for A3 ARs in rat coronary circulation. The magnitude of the coronary dilator response is reduced with age and does not involve A2A or A1 ARs.  相似文献   
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The Journal of Behavioral Health Services & Research - Few evidence-based psychotherapies are provided in adult public behavioral health (PBH), despite the need for such treatments. The common...  相似文献   
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Herpes simplex virus entry into cells requires four glycoproteins, gB, gD, gH, and gL. Binding of gD to one of its receptors triggers steps requiring the core fusion proteins, gB and the gH/gL heterodimer. There is evidence that gH/gL initiates hemifusion of cells, but whether this complex interacts physically with gB to cause complete fusion is unknown. We used bimolecular complementation (BiMC) of enhanced yellow fluorescent protein (EYFP) to detect glycoprotein interactions during cell-cell fusion. The N- or C-terminal half of EYFP was fused to the C terminus of gD, gB, and gH to form six chimeric proteins (Dn, Dc, Bn, Bc, Hn, and Hc). BiMC was detected by confocal microscopy. Receptor-bearing (C10) cells cotransfected with Dn and Bc or Dn, Hc, and untagged gL exhibited EYFP fluorescence, indicative of interactions between gD and gB and between gD and gH/gL. EYFP complementation did not occur in cells transfected with gL, Bc, and Hn. However, when gD was coexpressed with these other three proteins, cell-cell fusion occurred and the syncytia exhibited bright EYFP fluorescence. To separate glycoprotein expression from fusion, we transfected C10 cells with gL, Bc, and Hn for 20 h and then added soluble gD to trigger fusion. We detected fluorescent syncytia within 10 min, and both their number and size increased with exposure time to gD. Thus, when gD binds its receptor, the core fusion machinery is triggered to form a multiprotein complex as a step in fusion and possibly virus entry.  相似文献   
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