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1.
The circadian rhythm in humans is determined by the central clock located in the hypothalamus’s suprachiasmatic nucleus, and it synchronizes the peripheral clocks in other tissues. Circadian clock genes and clock-controlled genes exist in almost all cell types. They have an essential role in many physiological processes, including lipid metabolism in the liver, regulation of the immune system, and the severity of infections. In addition, circadian rhythm genes can stimulate the immune response of host cells to virus infection. Hepatitis B virus (HBV) infection is the leading cause of liver disease and liver cancer globally. HBV infection depends on the host cell, and hepatocyte circadian rhythm genes are associated with HBV replication, survival, and spread. The core circadian rhythm proteins, REV-ERB and brain and muscle ARNTL-like protein 1, have a crucial role in HBV replication in hepatocytes. In addition to influencing the virus’s life cycle, the circadian rhythm also affects the pharmacokinetics and efficacy of antiviral vaccines. Therefore, it is vital to apply antiviral therapy at the appropriate time of day to reduce toxicity and improve the effectiveness of antiviral treatment. For these reasons, understanding the role of the circadian rhythm in the regulation of HBV infection and host responses to the virus provides us with a new perspective of the interplay of the circadian rhythm and anti-HBV therapy. Therefore, this review emphasizes the importance of the circadian rhythm in HBV infection and the optimization of antiviral treatment based on the circadian rhythm-dependent immune response.  相似文献   
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BACKGROUND: Until there is a definitive demonstration that early diagnosis and treatment of prostate cancer reduces disease-related mortality, it is imperative to promote informed screening decisions by providing balanced information about the potential benefits and risks of prostate cancer screening. Within a community/academic collaboration, we conducted a randomized trial of a printed booklet and a videotape that were designed for African American (AA) men. The purpose of the trial was to determine the effect of the interventions on knowledge, decisional conflict, satisfaction with the screening decision, and self-reported screening. METHODS: Participants were 238 AA men, ages 40 to 70 years, who were members of the Prince Hall Masons in Washington, DC. Men were randomly assigned to the (a) video-based information study arm, (b) print-based information study arm, or (c) wait list control study arm. Intervention materials were mailed to men at home. Assessments were conducted at baseline, 1 month, and 12 months postintervention. Multivariate analyses, including ANCOVA and logistic regression, were used to analyze group differences. RESULTS: The booklet and video resulted in a significant improvement in knowledge and a reduction in decisional conflict about prostate cancer screening, relative to the wait list control. Satisfaction with the screening decision was not affected by the interventions. Self-reported screening rates increased between the baseline and the 1-year assessment, although screening was not differentially associated with either of the interventions. In exploratory analyses, prostate-specific antigen testing at 1 year was more likely among previously screened men and was associated with having low baseline decisional conflict. CONCLUSIONS: This study represents one of the first randomized intervention trials specifically designed to address AA men's informed decision making about prostate cancer screening. We have developed and evaluated culturally sensitive, balanced, and disseminable materials that improved knowledge and reduced decisional conflict about prostate cancer screening among AA men. Due to the high incidence and mortality rates among AA men, there is a need for targeted educational materials, particularly materials that are balanced in terms of the benefits and risks of screening.  相似文献   
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We have presented a rare case of primary involvement of the anterior mediastinum by osteogenic sarcoma in which CT was useful in demonstrating calcium within the mass, and in distinguishing the mass from surrounding bony structures. Although rare, extraosseous osteogenic sarcoma should be included in the differential diagnosis of a calcified anterior mediastinal mass.  相似文献   
5.
An unusual case of malignant melanoma metastatic to the lung and to the ovaries occurred 9 and 11 years, respectively, after the initial, extragenital diagnosis. The primary lesion invaded to Clark's level IV with a thickness of greater than 4 mm, normally grave prognostic indicators. A metastatic lung nodule seen radiographically remained unchanged for two years before discovery of the intraperitoneal disease. The case illustrates the clinical variability and unpredictable biologic behavior of malignant melanoma.  相似文献   
6.
The standard of care for patients with cholestasis (direct bilirubin >or=2 mg/dL) while receiving parenteral nutrition (PN) solutions is to reduce or discontinue the copper and manganese. The repercussions of this action have not been studied. Two adult case reports document low serum copper levels associated with clinical symptoms of copper deficiency after the removal of copper from their PN solutions. We now describe the first known series of pediatric patients to develop copper deficiency after copper was removed from their PN solutions.  相似文献   
7.
The results of the first 3 year' collaboration of the Italian Registry of Paediatric Chronic Peritoneal Dialysis (CPD) (1986–1988) are presented. This Registry acquired data on the majority of the paediatric patients treated with CPD in Italy, thus providing a national picture in a field where few nationwide surveys are available. Patients of less than 15 years of age at the start of dialysis were enrolled and clinical data collected until the age of 19 years. The number of nephrological paediatric centres participating in the Registry increased from 7 in 1986 to 11 in 1988. The total number of patients on CPD was 70 and the percentage of dialysed children treated with CPD ranged from 40.2% to 43.6%. Data on 89 peritoneal catheters were collected: during 1417 dialysis-months 70 catheter-related complications were observed (1:20.8 dialysis-months); actuarial catheter survival was 92.7% at 6 months, 84.8% at 1 year and 68.8% at 2 years. The incidence of peritonitis changed from 1 episode every 10.9 patient-months in 1986 to 1 every 19.8 in 1988. Abdominal hernias were the other main clinical complication observed. The survival of patients was 92.5% at 3 years, while the technique survival at the same time was 84%.  相似文献   
8.
The aim of this study was to evaluate the role of thromboxane A2 in bradykinin-induced airflow obstruction in guinea pig in vivo. Airway insufflation pressure (Pi) was measured to assess airflow obstruction and the thromboxane B2 (a stable metabolite of thromboxane A2) concentration in bronchoalvelolar lavage fluid was determined by radioimmunoassay. The animals were pretreated with propranolol (1 mg/kg i.v.) and suxamethonium (5 mg i.v.) prior to bradykinin administration. Bradykinin instillation into the trachea (300 nmol) induced a Pi increase (47.5 ± 8.3 cm H2O versus 23.8 ± 1.5 in sham) and significant thromboxane B2 release into bronchoalveolar lavage fluid (79 ± 19 pg/ml versus 19 ± 6 in sham). A thromboxane synthase inhibitor (OKY-046, 30 mg/kg i.v.; ((E-E)-3-[p(1H-imidazole-1-yl-methyl) phenyl]-2-propenoic acid hydrochloride mono-hydrate)) or a thromboxane A2 receptor antagonist (ICI192,605, 0.5 mg/kg i.v.; (4-(Z)-6-(2-o-chloro-phenyl-4-o-hydroxyphenyl-1,3-dioxan-cis-5-yl)hexenoic acid)) reduced the Pi increase evoked by bradykinin (38.7 ± 3.8 and 40.6 ± 3.8 cm H2O, respectively). OKY-046 abolished the thromboxane B2 release. A platelet-activating factor receptor antagonist, WEB2086 (1 mg/kg i.v.; (3-[4-(chlorophenyl)-9-methyl-6H-thienol [3,2-f][1,2,4]trizolo-[4,3-a][1,4] diazepin-2-yl]1-4-(4-morpholinyl)-1-propanon) did not significantly affect any measured parameter. We conclude that, in guinea pigs, bradykinin-induced airway effects are associated with a local thromboxane A2 release.  相似文献   
9.
Active T cell recognition of islet antigens has been postulated as the pathogenic mechanism in human type 1 diabetes, but evidence is scarce. If T cells are engaged, they are expected to display increased clonal size and exhibit a T helper (Th)1/Th2 differentiation state. We used a peptide library that covers tyrosine phosphatase IA-2, a target antigen expressed in pancreatic beta cells, to probe 8 diabetic patients and 5 HLA-matched controls. When tested in a high resolution IFNgamma/IL-4 double color ELISPOT assay directly ex vivo, the number of IA-2-reactive IFNgamma producing cells was 17-fold higher in patients than in controls and IL-4 producing cells were not present. An average of 9 peptides was recognized in the patients vs. one in the controls. Determinant recognition primarily involved CD4+ cells and showed high variability among the patients. Furthermore, anti-CD28 antibody signal enhances quantitative assessment of effector T cells in T1D patients. In vitro expansion with peptides and IL-2 results in detection of responding cells in the controls and loss of disease specificity of the T cell response. Together these data provide strong evidence for the active targeting of IA-2 by Th1 memory effector cells in human type 1 diabetes.  相似文献   
10.
Summary The presence of Epstein-Barr virus (EBV) genome in Hodgkin's and Reed-Sternberg (HRS) cells, as detected using in situ hybridization (ISH) with biotinylatedBamHI V probes, along with the expression of EBV-encoded latent membrane protein (LMP) and vimentin was examined in paraffin-embedded sections of 39 immunomorphologically characterized cases of Hodgkin's disease (HD). ISH demonstrated EBV in HRS cells in 15 of 39 cases, whereas LMP expression was detected in 11 of 39 cases, only in the presence of EBV genome detection. With the exception of 1 case, in which HRS cells expressed B-cell-associated antigens, the LMP-positive cases included specimens in which HRS cells were of non-B, non-T phenotype. LMP expression showed a stronger association with lymphocyte depletion (LD) (3/3) and mixed cellularity (MC) (6/11) than with lymphocyte predominance (0/5) or nodular sclerosis (2/20) subtypes. Vimentin expression on HRS cells was found in all the LMP-expressing cases and only in a fraction (13/28) of LMP-negative cases. This study supports the view that HD represents a heterogeneous group of diseases also in terms of EBV association, LMP expression being strongly related to the aggressive LD and MC histological subtypes. In light of the supposed interactions between vimentin and LMP, their coexpression on HRS cells, as detected in this study, provides further evidence for a significant role of EBV in the development of a proportion of HD cases.  相似文献   
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