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991.
Epidemiological data show that reproductive and hormonal factors are involved in the etiology of endometrial cancer, but there is little data on the association with endogenous sex hormone levels. We analyzed the association between prediagnostic serum concentrations of sex steroids and endometrial cancer risk in the European Prospective Investigation into Cancer and Nutrition using a nested case-control design of 247 incident endometrial cancer cases and 481 controls, matched on center, menopausal status, age, variables relating to blood collection, and, for premenopausal women, phase of menstrual cycle. Using conditional regression analysis, endometrial cancer risk among postmenopausal women was positively associated with increasing levels of total testosterone, free testosterone, estrone, total estradiol, and free estradiol. The odds ratios (ORs) for the highest versus lowest tertile were 2.66 (95% confidence interval (CI) 1.50-4.72; P=0.002 for a continuous linear trend) for estrone, 2.07 (95% CI 1.20-3.60; P=0.001) for estradiol, and 1.66 (95% CI 0.98-2.82; P=0.001) for free estradiol. For total and free testosterone, ORs for the highest versus lowest tertile were 1.44 (95% CI 0.88-2.36; P=0.05) and 2.05 (95% CI 1.23-3.42; P=0.005) respectively. Androstenedione and dehydroepiandrosterone sulfate were not associated with risk. Sex hormone-binding globulin was significantly inversely associated with risk (OR for the highest versus lowest tertile was 0.57, 95% CI 0.34-0.95; P=0.004). In premenopausal women, serum sex hormone concentrations were not clearly associated with endometrial cancer risk, but numbers were too small to draw firm conclusions. In conclusion, relatively high blood concentrations of estrogens and free testosterone are associated with an increased endometrial cancer risk in postmenopausal women.  相似文献   
992.
Chronic hepatitis may progress to cirrhosis and hepatocellular carcinoma (HCC). HCC represents one of the most common human cancers. Incidence rates for this tumor vary widely on a worldwide, suggesting that environmental factors such as infectious microorganisms, carcinogens, or nutrition play a role in its pathogenesis. Several Helicobacter spp. colonize the liver of animals and induce hepatitis. The aim of this study was to determine whether Helicobacter infection was associated with HCV-related liver diseases in humans. Liver tissue samples, including biopsy and surgically excised tissues, were collected from patients positive for hepatitis C viruses (HCV) RNA in the serum. Genomic DNA was extracted from sections of formalin-fixed paraffin-embedded tissues by using the QIAamp Tissue Kit and subjected to polymerase chain reaction (PCR) analysis using two sets of Helicobacter-specific 16S ribosomal RNA primers. To identify positive samples for H. pylori, a set of primers specific for a conserved region in the H. pylori vacA gene were also used. The patients' H. pylori status was determined by ELISA. Forty-one patients (mean age 54.9, range 19–78 years; 24 men) were studied. Thirty patients had chronic viral hepatitis (CH) without (N = 18) or with (N = 12) cirrhosis (CIR), and 11 patients had HCC. Anti-H. pylori IgG was detected in 54%. The expected 422- and 210-bp fragments of Helicobacter 16S rRNA were amplified from 27% of liver samples, including 17% of CH-CIR and 55% of HCC (P = 0.004). The vacA sequence was amplified in 10 of 41(24%) samples (27% of those with HCC).: These data confirm the presence of H. pylori DNA sequences in human liver and suggest an association of Helicobacter spp. with HCV-related chronic liver diseases. Further studies are needed to ascertain whether Helicobacter spp. infection plays a role in the development of HCC.  相似文献   
993.
OBJECTIVE: Sarcolipin (SLN) is a novel 31-amino-acid protein associated with the sarcoplasmic reticulum (SR) whose function in cardiac muscle is poorly defined. In this study, we tested the hypothesis that SLN is a regulator of SR Ca(2+) transport function by overexpressing SLN in adult rat ventricular myocytes which express low levels of SLN. METHODS: Expression of SLN mRNA in rat tissues was analyzed by Northern blot as well by RT-PCR analysis. To define the role of SLN in cardiac muscle contractility, we overexpressed SLN in adult rat ventricular myocytes using adenoviral gene transfer techniques. Localization of SLN in the adult rat ventricular myocytes was determined using confocal microscopy. Myocyte contractility and calcium transients were measured using edge detection and Fura 2AM. RESULTS: Our results demonstrate that overexpression of SLN decreased the cell shortening significantly when compared to control myocytes, whereas the time to peak contraction was not altered. In addition, SLN overexpression prolonged the time of 50% relaxation. Calcium transient analysis shows that time to 50% decay of [Ca(2+) ]i was markedly prolonged in SLN-overexpressing myocytes (control -245.0+/-3.78 vs. SLN -199.0+/-3.25 ms, p<0.001). However, there were no significant differences in peak amplitudes of [Ca(2+)](i) between SLN-overexpressing and control myocytes. We further demonstrate that SLN is localized within the SR membrane similar to PLB and SR Ca(2+) ATPase. Co-immunoprecipitation studies indicate that SLN can physically interact with phospholamban. CONCLUSIONS: We conclude that SLN may play an important role in regulating the SR calcium ATPase pump, possibly by interacting with phospholamban.  相似文献   
994.
OBJECTIVES: To determine whether older women with exudative age-related macular degeneration (AMD) are at greater risk of falls.
DESIGN: Cross-sectional study.
SETTING: A hospital-based ophthalmology clinic in Vancouver, Canada.
PARTICIPANTS: One hundred fifteen older (aged ≥70) community-dwelling women with exudative AMD (AMD cohort) and two control groups: 54 community-dwelling women without exudative AMD drawn from the same community (non-AMD cohort) and 341 community-dwelling Australian women (Australian normative cohort).
MEASUREMENTS: Participants were assessed for falls risk using the short-form Physiological Profile Assessment (PPA), which provides a fall risk index score and subcomponent measures of vision, proprioception, strength, reaction time, and postural sway.
RESULTS: The mean fall risk index score in the AMD cohort (3.20) was significantly greater than that of the non-AMD cohort (1.21; P <.001), and fall risk scores increased with age to a greater extent in the AMD cohort. The higher fall risk scores in the AMD cohort resulted from significantly worse performance on each PPA test, not just the test of vision. The AMD cohort also performed worse than the Australian normative cohort in tests of vision, reaction time, and postural sway.
CONCLUSION: Older women with AMD have impaired balance, slow visual reaction times, and poor vision, which in combination result in a significantly greater risk of falls than population norms. These deficits are clearly indicated in the physiological falls profile for the group. Strategies to enhance balance may be particularly beneficial to prevent falls in this group.  相似文献   
995.
OBJECTIVES: To study whether the growth hormone (GH) response after the subcutaneous administration 50 microg of octreotide (acute octreotide test) has any predictive value for long-term IGF-I normalization with Sandostatin LAR. DESIGN: Twenty four therapy-naive patients with active acromegaly were studied. RESULTS: > 75% GH decrease in the acute octreotide test predicted long-term IGF-I normalization with Sandostatin LAR in 8/11 (73%) of patients. 3/13 (23%) patients with < 75% GH decrease in the acute octreotide test were long-term biochemically controlled with Sandostatin LAR. Using the > 75% GH reduction criterion, the sensitivity and specificity of this test for predicting long-term normalization of serum IGF-I with Sandostatin LAR treatment were 73% and 77%, respectively (positive and negative predictive values: 73% and 77%, respectively). 6/8 (75%) patients with GH suppression to levels < 1.1 microg/l and 9/16 (56%) patients with GH suppression to levels < 2 microg/l in the acute octreotide test showed normalization of serum IGF-I with long-term Sandostatin LAR treatment. The sensitivity and specificity of GH suppression < 1.1 microg/l for predicting of the long-term normalization of serum IGF-I with Sandostatin LAR therapy were 55% and 85%, respectively (positive and negative predictive values: 75% and 69%, respectively). The sensitivity and specificity of GH suppression < 2 microg/l for predicting of the long-term normalization of serum IGF-I with Sandostatin LAR therapy were 82% and 46%, respectively (positive and negative predictive values: 56% and 75%, respectively). CONCLUSION: The acute octreotide is not recommended for clinical decision making with regard to long-term treatment using the long-acting somatostatin analog Sandostatin LAR in acromegaly.  相似文献   
996.
SUMMARY: Information about the character and grade of the intrahepatic immune response in viral hepatitis is important for the evaluation of disease stage and effect of therapy. Complications like haemorrhage limit the frequent performance of tissue-needle biopsies (TB), and the cells of peripheral blood have to be used as surrogate markers instead. Fine-needle-aspiration biopsy (FNAB) of the liver represents a safe and atraumatic method that allows frequent cytological sampling. Our aim was to investigate whether flow cytometry of FNAB specimens allows co-analysis of phenotype, function and specificity of key populations of liver-infiltrating lymphocytes (LIL). In 20 consecutive patients with chronic viral hepatitis [10 hepatitis B virus (HBV), 10 hepatitis C virus (HCV)], flow cytometry was performed on FNAB cytology, and simultaneously on lymphocytes isolated from a TB and peripheral blood mononuclear cells (PBMC). The ratio of CD8+/CD4+ lymphocytes in FNAB correlated well with LIL from TB (r =0.78, P < 0.05) but differed from PBMC (mean ratio: 2.6, 2.1 and 0.7, respectively). Similarly, a correlation was observed for percentage CD56+ natural killer (NK) cells (mean %: 29.9, 32.3 and 14.5, respectively; r = 0.69, P < 0.05). The percentage of interferon (IFN)-gamma-producing CD3+ lymphocytes in both FNAB and TB was higher than in PBMC (mean %: 41, 44 and 22, respectively; P < 0.05). Furthermore, tetrameric complexes allowed analysis of HBV-specific T cells in FNAB specimens. In conclusion, flow cytometry of FNAB allows easy, atraumatic and reliable analysis of lymphocytes obtained from the intrahepatic compartment. Therefore, the FNAB is a valuable tool in the study of the immunopathology of viral hepatitis, and it may contribute to the improved clinical evaluation of chronic viral liver disease.  相似文献   
997.
This study was undertaken to analyze the differentiation profiles assessed by immunophenotyping in AIDS-related B-cell lymphoma (ARL) and their relation to the clinical course. Paraffin-embedded sections of 89 ARL cases during 1989 to 2004 were stained immunohistochemically with antibodies to CD3, CD10, CD20, CD38, CD138/Syndecan-1 (Syn-1), multiple myeloma-1/interferon regulatory factor-4 (MUM1/IRF4), B-cell lymphoma protein-2 (BCL-2), BCL-6, latent membrane protein-1 (LMP-1), and Ki-67. Expression of CD10 and CD20 were associated with better overall survival (OS; P = .009 and P = .04, respectively). Expression of CD20 was associated with longer disease-free survival (DFS; P = .03), whereas expression of CD138/Syn-1 was associated with shorter DFS (P = .03). OS and DFS were worse in patients with immunophenotypic profiles related to post-germinal center (GC) differentiation (BCL-6 and CD10 negative, MUM1/IRF4 and/or CD138/Syn-1 positive) when compared with GC differentiation (P = .01). When controlled for age-adjusted International Prognostic Index (IPI), prior AIDS-defining illness (ADI), and year of ARL diagnosis, a post-GC differentiation remained significantly associated with poor OS and DFS. Expression of CD10 was associated with a preserved immunocompetence, whereas CD20 was less frequent in patients developing ARL while on highly active antiretroviral therapy (P = .04). In summary, lack of CD20 or CD10 expression and a post-germinal center signature are associated with a worse prognosis in ARL.  相似文献   
998.
This paper reports the isolation of St. Louis encephalitis virus (SLEV) from a febrile human case suspected to be dengue, in S?o Pedro, S?o Paulo State. A MAC-ELISA done on the patient's acute and convalescent sera was inconclusive and hemagglutination inhibition test detected IgG antibody for flaviviruses. An indirect immunofluorescent assay done on the C6/36 cell culture inoculated with the acute serum was positive for flaviviruses but negative when tested with dengue monoclonal antibodies. RNA extracted from the infected cell culture supernatant was amplified by RT-PCR in the presence of NS5 universal flavivirus primers and directly sequenced. Results of BLAST search indicated that this sequence shares 93% nucleotide similarity with the sequence of SLEV (strain-MSI.7), confirmed by RT-PCR performed with SLEV specific primers. Since SLEV was identified as the cause of human disease, it is necessary to improve surveillance in order to achieve early detection of this agent in the state of S?o Paulo and in Brazil. This finding is also an alert to health professionals about the need for more complete clinical and epidemiological investigations of febrile illnesses as in the reported case. SLEV infections can be unrecognized or confused with other ones caused by an arbovirus, such as dengue.  相似文献   
999.

Background

H. pylori (Hp) infection is a major risk factor in gastric carcinogenesis leading to epithelial mutagenesis, and may affect gastric epithelial stem cells.

Aims

To characterize the expression of Lgr5, a marker of epithelial stem cells in human gastric mucosa, to determine whether Hp infection affects Lgr5-positive epithelial cells (LPECs) and whether LPECs are susceptible to DNA damage associated with Hp infection.

Methods

Lgr5 expression was characterized in non-neoplastic gastric mucosa from 52 patients (34 with and 18 without gastric cancer (GC); 21 Hp-positive (Hp+) and 31 Hp-negative (Hp?)) by immunohistochemical and immunofluorescence staining. To determine the extent of DNA damage in LPECs, nuclear 8-hydroxydeoxyguanosine (8OHdG), a marker of DNA damage associated with oxidative stress, was measured by quantitative spectral image analysis.

Results

LPECs were primarily present in gastric antrum. Higher numbers of LPECs were seen in Hp+ than in Hp? non-neoplastic mucosa of GC patients, P = .006, but not in patients without GC. 8OHdG levels in LPECs were significantly higher than in Lgr5-negative epithelial cells in Hp+ GC patients (P = .012) but not in Hp? cases (P = .414), whereas no difference was seen between Hp+ and Hp? mucosa of patients without GC.

Conclusions

The Lgr5-positive epithelial stem cell pool is expanded in Hp-associated gastritis in the antrum of patients with GC. In GC patients with active Hp infection, LPECs may be more susceptible to DNA damage than Lgr5-negative epithelial cells, suggesting that Hp infection may contribute to GC risk by affecting epithelial stem cells in the human stomach.  相似文献   
1000.
AimMid-life obesity is associated with T2D risk. However, less is known about the cumulative effect of obesity during adulthood.MethodsFramingham Offspring Study participants who had an examination at 35 ± 2 years and were initially free of T2D were included in this study (N = 1026). A cumulative excess weight (CEW) score (year*kg/m2) was calculated until T2D diagnostic or the end of follow-up.ResultsEighty-four individuals (8.2%) developed T2D over 20 ± 6 years. Mean CEW scores were 118.0 ± 114.6 year*kg/m2 in individuals who developed T2D and 30.2 ± 91.4 year*kg/m2 in those who did not develop T2D (P < 0.01). T2D risk was doubled for each standard deviation increase in the CEW score (OR = 1.99 [1.64-2.40]; P < 0.001). However, CEW score was only significantly associated with T2D incidence for participants with a baseline BMI < 25 kg/m2 (OR = 2.13 [1.36–3.36]; P < 0.001).ConclusionsAccumulating weight between the mid-thirties to the mid-fifties increases the risk of developing T2D. However, BMI in mid-thirties remains a stronger predictor of T2D risk.  相似文献   
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