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41.
Infection of human macrophages with Salmonella enterica serovar Typhimurium or Salmonella enterica serovar Dublin produces delayed cytotoxicity characterized by cell detachment and associated apoptosis. Using a site-specific mutant in the SpvB active site, we verify that the ADP-ribosylation activity of SpvB is required for delayed cytotoxicity in human macrophages infected with Salmonella: SipB and the type III protein secretion system (TTSS) encoded by Salmonella pathogenicity island 1 (SPI1) are not involved, whereas the SPI2 TTSS is absolutely required for SpvB-dependent cytotoxicity. Furthermore, we show that infection of macrophage cultures with wild-type or sipB mutant bacteria led to a complete loss of polymerized actin in over half of the cells after 24 h. In contrast, macrophages infected with the spvB or SPI2 (ssaV or ssaJ) mutant strain retained normal F-actin filaments, despite similar numbers of intracellular bacteria. We conclude that SpvB and a functional SPI2 TTSS are essential for Salmonella-induced delayed cytotoxicity of human macrophages.  相似文献   
42.
The D-amino acid oxidase (DAO) signaling pathway has been implicated in schizophrenia pathogenesis. This may be mediated through modulation of NMDA function by DAO, which is in turn activated by DAO activator (DAOA, formerly G72). Chumakov et al. (2002); PNAS 99: 13675-13680, identifying the novel schizophrenia susceptibility gene DAOA/G30 and a number of independent studies have since reported evidence of association between the DAOA and DAO genes and schizophrenia. However, at least two studies have failed to replicate the epistatic interaction between these loci described in the original report and there have been differences in the associated alleles/haplotypes reported at each locus. In this study, we performed association and epistasis analyses of the DAOA/G30 and DAO loci in a sample of 373 cases with DSM-IV schizophrenia/schizoaffective disorder and 812 controls from the Republic of Ireland. Corrected for the number of tests performed, we found evidence for association between markers at both genes and schizophrenia: DAOA/G30 (P = 0.005, OR = 1.34 (1.09, 1.65)) and DAO (P = 0.003, OR = 1.43 (1.12, 1.84). The data suggest that evidence for association at DAO (marker rs2111902) is more consistent than previously realized, particularly in Caucasian schizophrenia populations. We identified evidence for epistatic interaction between the associated SNPs at DAOA and DAO genes in contributing to schizophrenia risk (OR = 9.3 (1.4, 60.5). Based on these data, more systematic investigation of genes involved in DAO signaling is required.  相似文献   
43.
Often, it is difficult to distinguish follicular lymphoma from reactive follicular hyperplasia histologically. Immunotypic evidence of monoclonality cannot be demonstrated routinely or reliably in routine paraffin-embedded sections. To determine whether a panel of monoclonal antibodies reactive with lymphoid cells in paraffin-embedded sections might be useful in distinguishing these confusing proliferations, the authors examined 45 follicular lymphomas and 30 follicular hyperplasia with the following antibodies; L26, B2, MT1, MT2, and UCHL-I. All sections were routine paraffin preparations from formalin- or B5-fixed tissue and were immunostained with the avidin-biotin immunoperoxidase technique. Ninety-two percent of the B5-fixed and 77% of the formalin-fixed lymphomas were MT2 positive. None of the reactive hyperplasias stained positively, and none of the other antibodies demonstrated consistent differences between these benign and malignant proliferations. MT2 marks interfollicular T cells and mantle-zone B cells in normal lymph nodes but does not mark normal germinal centers; this staining pattern is retained in reactive hyperplasia. However, paradoxically, in most follicular lymphomas the neoplastic germinal centers show aberrant MT2 positively. The authors conclude that MT2 may be useful in distinguishing follicular lymphoma from follicular hyperplasia in paraffin sections.  相似文献   
44.
The study of in vivo occupancy of benzodiazepine receptors in rat hippocampus and cerebellum indicates that premazepam reaches only about 70% and 80% occupancy respectively within the dose range used for pharmacological tests in rats. Moreover, at equiactive doses (antileptazol ED50), more brain receptors are occupied by premazepam than by other benzodiazepines, suggesting that premazepam may act as a partial agonist at benzodiazepine receptors, with intrinsic activity lower in cerebellum than in hippocampus. These results may explain the lack of sedative and ataxic properties of premazepam.  相似文献   
45.
A model for concordance in a binary measure that does not rely on the assumption of an underlying latent liability dichotomized about a threshold has been demonstrated for twin pairs [Hannah et al, 1983]. It is extended here to pedigrees of arbitrary structure by making an assumption that is, for small incidence rates, almost equivalent to postulating that relative risks are multiplicative. The model is applied to the workshop data to determine the extent to which the known structure of the simulated models can be recovered.  相似文献   
46.
Journal of Public Health - The purpose of this paper is to investigate the implementation of value-based care principles in the context of frailty in the perioperative process, highlighting the...  相似文献   
47.
Maternal and Child Health Journal - Adverse childhood experiences (ACEs) are associated with poor physical and mental health outcomes in pregnancy, prompting many care agencies to ask about ACEs as...  相似文献   
48.
We developed an assay that detects minus-strand RNA as a surrogate for actively replicating severe acute respiratory syndrome coronavirus 2. We detected minus-strand RNA in 41 persons with coronavirus disease up to 30 days after symptom onset. This assay might inform clinical decision-making about patient infectiousness.  相似文献   
49.

It is critical to understand what happens when PrEP patients are lost-to-follow-up (LTFU) and, where appropriate, attempt to re-engage them in care with the goal of preventing future human immunodeficiency virus (HIV) acquisition. We evaluated the benefits and limitations of using text-based outreach to re-engage with LTFU PrEP patients and offer re-initiation of PrEP care. Using text-messaging, we surveyed San Francisco City Clinic patients who started PrEP from January 2015 to October 2019 and were LTFU by October 1, 2020. Our goals were to better understand (1) whether our patients remained on PrEP through another provider or source, (2) why patients choose to discontinue PrEP, and (3) whether text-based outreach could successfully re-engage such patients in care. Multiple-choice survey questions were analyzed quantitatively to determine the proportion of respondents selecting each option; free-text responses were analyzed qualitatively using an inductive approach to identify any additional recurring themes. Of 846 eligible survey recipients, 130 responded (overall response rate 15.4%). Forty-two respondents (32.3%) were still on PrEP through another provider while 88 (67.7%) were not. Common reasons for stopping PrEP included: COVID-19–related changes in sex life (32.3% of responses), concerns regarding side effects (17.7%), and the need to take a daily pill (8.3%). Free text responses revealed additional concerns regarding risk compensation. While 32 participants agreed to be contacted by City clinic staff for PrEP counseling, only 6 were reached by phone and none of the six subsequently restarted PrEP. We learned that text messaging is a possible approach to survey certain PrEP program participants to determine who is truly LTFU and off PrEP, and to better understand reasons for PrEP discontinuation. While such information could prove valuable as programs seek to address barriers to PrEP retention, efforts to improve acceptability and increase response rates would be necessary. We were less successful in re-engaging LTFU patients in PrEP care, suggesting that text-messaging may not be the optimal strategy for this purpose.

  相似文献   
50.
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