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71.
Bone marrow transplant recipients are at risk for acquiring hepatitis C infection from the donated marrow. Twelve patients who were hepatitis C virus (HCV) RNA-negative pretransplant received marrow from anti-HCV seropositive donors. HCV RNA was present in the sera of seven of these donors. After transplant, serial serum specimens were obtained from all marrow recipients for determination of HCV RNA and aminotransferase levels. All seven recipients of marrow from HCV RNA-positive donors were HCV RNA-positive after marrow infusion; none cleared virus from the serum. All five recipients of marrow from anti-HCV seropositive, HCV RNA-negative donors remained free of HCV RNA in serum up to day 100. Abnormal serum aminotransferases were common in both HCV RNA- negative and HCV RNA-positive marrow recipients. One HCV-infected recipient developed marked elevation in aminotransferases after immunosuppressive drugs were stopped. We conclude that the presence of HCV RNA in the serum of marrow donors is an accurate predictor of HCV infection in marrow recipients. The acute infection was subclinical in all patients. The long-term risk of chronic hepatitis C virus infection in these patients remains to be determined.  相似文献   
72.
BackgroundCigarette smoking is a risk factor for severe COVID-19 disease. Understanding smokers’ responses to the pandemic will help assess its public health impact and inform future public health and provider messages to smokers.ObjectiveTo assess risk perceptions and change in tobacco use among current and former smokers during the COVID-19 pandemic.DesignCross-sectional survey conducted in May–July 2020 (55% response rate)Participants694 current and former daily smokers (mean age 53, 40% male, 78% white) who had been hospitalized pre-COVID-19 and enrolled into a smoking cessation clinical trial at hospitals in Massachusetts, Pennsylvania, and Tennessee.Main MeasuresPerceived risk of COVID-19 due to tobacco use; changes in tobacco consumption and interest in quitting tobacco use; self-reported quitting and relapse since January 2020.Key Results68% (95% CI, 65–72%) of respondents believed that smoking increases the risk of contracting COVID-19 or having a more severe case. In adjusted analyses, perceived risk was higher in Massachusetts where COVID-19 had already surged than in Pennsylvania and Tennessee which were pre-surge during survey administration (AOR 1.56, 95% CI, 1.07–2.28). Higher perceived COVID-19 risk was associated with increased interest in quitting smoking (AOR 1.72, 95% CI 1.01–2.92). During the pandemic, 32% (95% CI, 27–37%) of smokers increased, 37% (95% CI, 33–42%) decreased, and 31% (95% CI, 26–35%) did not change their cigarette consumption. Increased smoking was associated with higher perceived stress (AOR 1.49, 95% CI 1.16–1.91). Overall, 11% (95% CI, 8–14%) of respondents who smoked in January 2020 (pre-COVID-19) had quit smoking at survey (mean, 6 months later) while 28% (95% CI, 22–34%) of former smokers relapsed. Higher perceived COVID-19 risk was associated with higher odds of quitting and lower odds of relapse.ConclusionsMost smokers believed that smoking increased COVID-19 risk. Smokers’ responses to the pandemic varied, with increased smoking related to stress and increased quitting associated with perceived COVID-19 vulnerability.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11606-021-06913-3.KEY WORDS: cigarette smoking, electronic cigarettes, COVID-19, risk perceptions  相似文献   
73.
BACKGROUND & AIMS: Murine autoimmune gastritis, induced by day-3 thymectomy, is characterized by cellular infiltrates and circulating autoantibodies to gastric hydrogen/potassium adenosine triphosphatase. The aim of this study was to analyze the cellular infiltrates and cytokines in autoimmune gastritis. METHODS: Stomachs and blood samples from day-3 thymectomized BALB/c mice were obtained from 2 to 12 weeks after thymectomy for analysis. RESULTS: At 4 weeks, the gastritic infiltrates were composed of macrophages and CD4+ T cells, accompanied by major histocompatibility complex class II expression on gastric epithelial cells. Mucosal B cells, scant at 4 weeks, were abundant at 8 weeks, coincident with the peaking of autoantibodies to gastric hydrogen/potassium adenosine triphosphatase. CD8+ T cells increased marginally during the 12 weeks. Mononuclear cells from diseased stomachs transferred gastritis to nu/nu recipients. At 4 weeks, interleukins 2, 3, 5, 6, and 10; interferon gamma; tumor necrosis factor alpha; and granulocyte-macrophage colony-stimulating factor were detected in gastritic mucosa, but interleukin 4 was not. CONCLUSIONS: The early lesion of autoimmune gastritis is composed of macrophages and CD4+ T cells with major histocompatibility complex class II expression in gastric epithelial cells. Autoantibody production is a late event. Our results are consistent with a lesion mediated by CD4+ T cells producing a mix of Th1- and Th2-type cytokines. (Gastroenterology 1996 Jun;110(6):1791-802)  相似文献   
74.
Increasing the expression of the gamma globin genes is considered a useful therapeutic approach to the beta globin diseases. Because butyrate and alpha-amino-n-butyric acid (ABA) augment gamma globin expression in normal neonatal and adult erythroid progenitors, we investigated the effects of sodium butyrate and ABA on erythroid progenitors of patients with beta thalassemia and sickle cell anemia who might benefit from such an effect. Both substances increased fetal hemoglobin (Hb F) expression in Bfu-e from 7% to 30% above levels found in control cultures from the same subjects with sickle cell anemia. The fraction of cultured erythroblasts producing Hb F increased more than 20% with sodium butyrate treatment in 70% of cultures. In most cultures, this produced greater than 20% total Hb F and greater than 70% F cells, levels which have been considered beneficial in ameliorating clinical symptoms. Alpha: non-alpha (alpha-non-alpha) imbalance was decreased by 36% in erythroid progenitors of patients with beta thalassemia cultured in the presence of butyrate compared with control cultures from the same subjects. These data suggest that sodium butyrate may have therapeutic potential for increasing gamma globin expression in the beta globin diseases.  相似文献   
75.
Though larger social networks are associated with reduced breast cancer mortality, there is a need to clarify how both social support and social burden influence this association. We included 4,530 women from the Women’s Health Initiative who were diagnosed with breast cancer between 1993 and 2009, and provided data on social networks (spouse or intimate partner, religious ties, club ties, and number of first-degree relatives) before diagnosis. Of those, 354 died during follow-up, with 190 from breast cancer. We used Cox proportional hazards regression to evaluate associations of social network members with risk of post-diagnosis mortality, further evaluating associations by social support and social burden (caregiving, social strain). In multivariate-adjusted analyses, among women with high but not low social support, being married was related to lower all-cause mortality. By contrast, among women with high but not low social burden, those with a higher number of first-degree relatives, including siblings, parents, and children, had higher all-cause and breast cancer mortality (among caregivers: 0–3 relatives (ref), 4–5 relatives, HR = 1.47 (95% CI: 0.62–3.52), 6–9 relatives, HR = 2.08 (95% CI: 0.89–4.86), 10+ relatives, HR = 3.55 (95% CI: 1.35–9.33), P-continuous = 0.02, P-interaction = 0.008). The association by social strain was similar though it was not modified by level of social support. Other social network members were unrelated to mortality. Social relationships may have both adverse and beneficial influences on breast cancer survival. Clarifying these depends on understanding the context of women’s relationships.  相似文献   
76.
BACKGROUND: One of the most recognizable features of psychopathy is the reduced ability to successfully learn and adapt overt behavior. This might be due to deficient processing of error information indicating the need to adapt controlled behavior. METHODS: Event-related potentials (ERPs) and behavioral components of error-monitoring processes were investigated in 16 individuals with psychopathy and in 18 healthy subjects. A letter version of the Eriksen flanker task was used in two conditions. The first condition (normal condition) required participants to press one of two buttons depending on the identity of the target stimulus. The second condition (signaling condition) required them to signal each time they had committed an error by making a second press on a signaling button. Early stages of error monitoring were investigated by using the error-related negativity (ERN/Ne) and post-error slowing as indexes. Later stages were explored by examining the error positivity (Pe) and signaling rates. RESULTS: Both groups showed similar ERN amplitudes and amounts of post-error slowing. The psychopathic group exhibited both reduced Pe amplitudes and diminished error-signaling rates compared with the control group. CONCLUSIONS: Individuals with psychopathy show intact early error processing and automatic behavioral adaptation but have deficits in later stages of error processing and controlled behavioral adaptation. This is an indication that individuals with psychopathy are unable to effectively use error information to change their behavior adequately.  相似文献   
77.
More than one in five American adults still smokes despite the availability of effective smoking cessation medication. Genetic predisposition to treatment response, termed pharmacogenetics, offers a potential (if partial) solution to this widespread public health problem. Recent genomewide association studies have identified a group of “quit-success genes” that are specific for predicting response to bupropion versus nicotine replacement therapy. However, additional research is needed to replicate and refine these exciting discoveries; their medical practice and policy implications are vast. A public health infrastructure is not yet in place to translate the knowledge of quit-success genes into primary care practice, where most smoking cessation treatment takes place.  相似文献   
78.
Concurrent chemotherapy and radiation (CT/RT) for localized oesophageal cancer can cause life-threatening myelo-suppression. This non-randomized study examines 95 patients from three Australasian centres treated on the Trans-Tasman Radiation Oncology ‘definitivechemoradiation ‘ study. Duration of fluorouracil infusion and patient age were independently predictive of myelotoxicity after the first cycle of CT/RT. Overall rates of grade III and IV neutropaenia were 23% and of thrombocytopaenia 8% following the first cycle of chemotherapy. Five neutropaenic septic episodes followed the first cycle and six the second. All five patients recovered after the first cycle but there were four treatment-related deaths occurring after the second cycle of CT/RT. Recommendations are made concerning initial dosing, dose reductions and delays to minimize adverse patient outcomes from myelosuppression.  相似文献   
79.
80.
Tissues from 22 cases of nodular sclerosing Hodgkin's disease were studied by light and electron microscopy in conjunction with immunohistologic and cytochemical staining. The presence of lipid in the cytoplasm of lacunar cells suggested that this was responsible for the distinctive "lacunar" appearance of the cells. Marked morphologic similarities between "blast cells" resulting from mitogen stimulation of lymphocytes in vi-ro, immunoblasts seen in reactive lymphoid tissues, and mononuclear "Hodgkin's" cells in Hodgkin's disease suggested that all three cell types may result from lymphocyte transformation. It also seemed apparent that there was a developmental sequence from lymphocyte to transformed lymphocyte to the abnormal mononuclear Hodgkin's cell, with further progression, through increasing size and nuclear lobulation, to the lacunar cell or, alternatively, to the diagnostic Reed-Sternberg cell. This proposed sequence was supported by immunoperoxidase studies in which cytoplasmic immunoglobulin was demonstrated in mononuclear Hodgkin's cells, lacunar cells and Reed-Sternberg cells. The proposed relationship between these cells was also supported by the findings of both kappa and lambda chains in the same cells, a pattern not seen in reactive transformed lymphocytes.  相似文献   
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