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81.
AIM:To report a patient with C282Y homozygocity,depleted body iron and intestinal atrophy caused by celiac disease (CD) who experienced resolution of the enteropathy with subsequent normalization of iron metabolism upon gluten free diet. METHODS:To obtain information on the tissue distribution and quantitative expression of proteins involved in duodenal iron trafficking,we determined the expression of divalent-metal transporter 1 (DMT1),ferroportin 1 (FP1) and transferrin receptor (TfR1) by means of immunohist-ochemistry and real-time PCR in duodenal biopsies of this patient. RESULTS:Whereas in hereditary hemochromatosis patients without CD, DMT1 expression was up-regulated leading to excessive uptake of iron, we identified a significant reduction in protein ana mRNA expression of DMT1 as a compensatory mechanism in this patient with HH and CD. CONCLUSION:Occult CD may compensate for increased DMT1 expression in a specific subset of individuals with homozygous C282Y mutations in the hemochromatosis (HFE) gene,thus contributing to the low penetrance of HH.  相似文献   
82.
OBJECTIVES: The purpose of this work was to determine the predictive value of oxidized phospholipids (OxPLs) present on apolipoprotein B-100 particles (apoB) in carotid and femoral atherosclerosis. BACKGROUND: The OxPLs are pro-inflammatory and pro-atherogenic and may be detected using the antibody E06 (OxPL/apoB). METHODS: The Bruneck study is a prospective population-based survey of 40- to 79-year-old men and women initiated in 1990. Plasma levels of OxPL/apoB and lipoprotein (a) [Lp(a)] were measured in 765 of 826 (92.6%) and 671 of 684 (98.1%) subjects alive in 1995 and 2000, respectively, and correlated with ultrasound measures of carotid and femoral atherosclerosis. RESULTS: The distribution of the OxPL/apoB levels was skewed to lower levels and nearly identical to Lp(a) levels. The OxPL/apoB and Lp(a) levels were highly correlated (r = 0.87, p < 0.001), and displayed long-term stability and lacked correlations with most cardiovascular risk factors and lifestyle variables. The number of apolipoprotein (a) kringle IV-2 repeats was inversely related to Lp(a) mass (r = -0.48, p < 0.001) and OxPL/apoB levels (r = -0.46, p < 0.001). In multivariable analysis, OxPL/apoB levels were strongly and significantly associated with the presence, extent, and development (1995 to 2000) of carotid and femoral atherosclerosis and predicted the presence of symptomatic cardiovascular disease. Both OxPL/apoB and Lp(a) levels showed similar associations with atherosclerosis severity and progression, suggesting a common biological influence on atherogenesis. CONCLUSIONS: This study suggests that pro-inflammatory oxidized phospholipids, present primarily on Lp(a), are significant predictors of the presence and extent of carotid and femoral atherosclerosis, development of new lesions, and increased risk of cardiovascular events. The OxPL biomarkers may provide valuable insights into diagnosing and monitoring cardiovascular disease.  相似文献   
83.
OBJECTIVEAssess the prevalence of nonalcoholic fatty liver disease (NAFLD) and of liver fibrosis associated with nonalcoholic steatohepatitis in unselected patients with type 2 diabetes mellitus (T2DM).RESEARCH DESIGN AND METHODSA total of 561 patients with T2DM (age: 60 ± 11 years; BMI: 33.4 ± 6.2 kg/m2; and HbA1c: 7.5 ± 1.8%) attending primary care or endocrinology outpatient clinics and unaware of having NAFLD were recruited. At the visit, volunteers were invited to be screened by elastography for steatosis and fibrosis by controlled attenuation parameter (≥274 dB/m) and liver stiffness measurement (LSM; ≥7.0 kPa), respectively. Secondary causes of liver disease were ruled out. Diagnostic panels for prediction of advanced fibrosis, such as AST-to-platelet ratio index (APRI) and Fibrosis-4 (FIB-4) index, were also measured. A liver biopsy was performed if results were suggestive of fibrosis.RESULTSThe prevalence of steatosis was 70% and of fibrosis 21% (LSM ≥7.0 kPa). Moderate fibrosis (F2: LSM ≥8.2 kPa) was present in 6% and severe fibrosis or cirrhosis (F3–4: LSM ≥9.7 kPa) in 9%, similar to that estimated by FIB-4 and APRI panels. Noninvasive testing was consistent with liver biopsy results. Elevated AST or ALT ≥40 units/L was present in a minority of patients with steatosis (8% and 13%, respectively) or with liver fibrosis (18% and 28%, respectively). This suggests that AST/ALT alone are insufficient as initial screening. However, performance may be enhanced by imaging (e.g., transient elastography) and plasma diagnostic panels (e.g., FIB-4 and APRI).CONCLUSIONSModerate-to-advanced fibrosis (F2 or higher), an established risk factor for cirrhosis and overall mortality, affects at least one out of six (15%) patients with T2DM. These results support the American Diabetes Association guidelines to screen for clinically significant fibrosis in patients with T2DM with steatosis or elevated ALT.  相似文献   
84.
Thymic atrophy is known to occur during infections; however, there is limited understanding of its causes and of the cross-talk between different pathways. This study investigates mechanisms involved in thymic atrophy during a model of oral infection by Salmonella enterica serovar Typhimurium (S. typhimurium). Significant death of CD4+ CD8+ thymocytes, but not of single-positive thymocytes or peripheral lymphocytes, is observed at later stages during infection with live, but not heat-killed, bacteria. The death of CD4+ CD8+ thymocytes is Fas-independent as shown by infection studies with lpr mice. However, apoptosis occurs with lowering of mitochondrial potential and higher caspase-3 activity. The amounts of cortisol, a glucocorticoid, and interferon-γ (IFN-γ), an inflammatory cytokine, increase upon infection. To investigate the functional roles of these molecules, studies were performed using Ifnγ−/− mice together with RU486, a glucocorticoid receptor antagonist. Treatment of C57BL/6 mice with RU486 does not affect colony-forming units (CFU), amounts of IFN-γ and mouse survival; however, there is partial rescue in thymocyte death. Upon infection, Ifnγ−/− mice display higher CFU and lower survival but more surviving thymocytes are recovered. However, there is no difference in cortisol amounts in C57BL/6 and Ifnγ−/− mice. Importantly, the number of CD4+ CD8+ thymocytes is significantly higher in Ifnγ−/− mice treated with RU486 along with lower caspase-3 activity and mitochondrial damage. Hence, endogenous glucocorticoid and IFN-γ-mediated pathways are parallel but synergize in an additive manner to induce death of CD4+ CD8+ thymocytes during S. typhimurium infection. The implications of this study for host responses during infection are discussed.  相似文献   
85.
An increasing body of evidence connects alterations in the process of alternative splicing with cancer development and progression. However, a direct role of splicing factors as drivers of cancer development is mostly unknown. We analysed the gene copy number of several splicing factors in colon and lung tumours, and found that the gene encoding for the splicing factor SRSF6 is amplified and over‐expressed in these cancers. Moreover, over‐expression of SRSF6 in immortal lung epithelial cells enhanced proliferation, protected them from chemotherapy‐induced cell death and converted them to be tumourigenic in mice. In contrast, knock‐down of SRSF6 in lung and colon cancer cell lines inhibited their tumourigenic abilities. SRSF6 up‐ or down‐regulation altered the splicing of several tumour suppressors and oncogenes to generate the oncogenic isoforms and reduce the tumour‐suppressive isoforms. Our data suggest that the splicing factor SRSF6 is an oncoprotein that regulates the proliferation and survival of lung and colon cancer cells.  相似文献   
86.

Background

Social adjustment is impaired in depressed patients. The difficulty to adjust to social circumstances has been hypothesized to be one of the causes of depression, as well as a consequence of the disorder. Genetic variation in the serotonin transporter gene has been previously associated with social adjustment levels in patients with mood disorders.

Methods

We investigated whether variations on the HTR1A (rs6295) and HTR2A (rs7997012) genes were associated with levels of social adjustment using the Social Adjustment Scale in two samples of depressed patients (total n=156).

Results

Patients carrying the GG genotype of the HTR2A-rs7997012 showed better social adjustment in areas of work and family unit bonding.

Limitations

These findings did not survive correction for multiple testing and should be interpreted with caution.

Conclusion

Our finding is in line with previous observations that have associated the G allele of the HTR2A-rs7997012 with higher rate of antidepressant response. The HTR2A-rs7997012 is worthy of further investigation in studies examining factors that are related to depression course and outcome.  相似文献   
87.
Normoglycemic diabetes-prone BB/OK rats aged 33, 45 or 75 days were subjected to prophylactic insulin treatment by means of a single subcutaneous application of a sustained release insulin implant. The single application of a sustained release insulin implant decreased the incidence of diabetes or delayed the onset of the disease in BB/OK rats of all treatment groups. Prophylactic insulin administration caused a transient hypoglycemic period accompanied by an inhibition of glucose stimulated insulin secretion and a decrease of the insulin content of Langerhans' islets as detectable in vitro . Compared to islets of normoglycemic controls pancreatic islets isolated from hypoglycemic BB/OK rats within 7-21 days after the insulin application at 45 days of age displayed a decreased susceptibility of the cells to complement-dependent cytotoxicity of the monoclonal islet cell surface antibody (ICSA) K14D10 but not to the cytotoxic effect of the ICSA M3aG8. The appearance of complement-dependent antibody-mediated cytotoxicity to islet cells and pancreatic exocrine cells in serum regarded as a sign of immune dysregulation in BB/OK rats seems not to be affected by insulin prophylaxis and was detectable during hypoglycemia as well as in the subsequent normoglycemic state. In conclusion, BB/OK rats of different age can be protected from diabetes by a single application of a sustained release insulin implant. Insulin and/or hypoglycemia seem to influence the expression of cell surface antigens, thus render the islets of Langerhans less vulnerable to immune cytolysis, whereas the appearance of humoral immunological abnormalites is not affected.  相似文献   
88.
Introduction: Quadriceps angle (Q angle) is one of the most important indicators of stability of patello-femoral joint. Orthopedic surgeons often measure the Q angle clinically in patients suffering from patello-femoral joint dysfunction or in subjects particularly young active sportspersons who are prone to injury of this joint. But the clinical method of measurement of Q angle is not standardized, and its value depends on various methods used. But the radiological method of measurement of Q angle is more accurate. However, due to the expense and time involved, the clinical method is preferred over the radiological one in practice. Aim: This study was aimed at studying the correlation and regression between the radiographic Q-angle values and the clinical ones, so that the former can be predicted easily from the latter. Materials and methods: Q angle was measured both clinically and radiographically in both knee joints of 93 adult subjects in North Bengal Medical College and Hospital. Result: Statistically significant correlation followed by the regression analysis could reveal simple linear regression equations for predicting the radiological Q-angle values from the clinical Q angle, derived separately in both males and females in right and left sides, separately. Conclusion: Thus, from a known clinical Q-angle value, we can derive the respective radiological Q angle, indirectly avoiding the entire troublesome maneuver in regular practice. So the present study recommends this method in clinical fields because this is a more rational and ideal approach to estimate the radiological Q angle. Increase in the Q angle beyond 20–22° predisposes to patellar dislocation which should be kept in mind while screening athletes, especially females. This tendency can be countered by quadriceps exercises and appropriate footwear.  相似文献   
89.
目的: 植体周围一定程度的骨丧失可能会给牙种植治疗的美观效果带来不利影响。这种情况可能更容易影响软组织水平(Tissue-Level, TL)设计,因此,当强调形态的美观自然性时,骨组织水平(Bone-Level, BL)设计可能更有优势。除了植体的设计,牙龈生物型也被认为是维持牙槽骨稳定的重要因素。本研究拟针对具有不同牙龈生物型的患者,在其美学区域行软组织水平和骨水平牙种植治疗,探究其骨丧失的程度。材料和方法: 对41位患者行20个TL和22个BL种植治疗,术后即刻、术后随访对这42个位点行口内影像学检查;运用计算机技术行牙槽骨高度测量分析;运用TRAN法鉴定患者的牙龈生物型。结果: TL组平均4.9年的存留期里,厚龈型的12颗植体周围平均骨丧失0.21mm(SD:0.43mm);薄龈型的8颗植体周围平均骨丧失0.05mm(SD:0.47mm;P=0.31)。BL组平均1.9年的存留期里,厚龈型的14颗植体周围骨丧失为-0.03mm(SD:0.38mm),薄龈型的8颗植体周围骨丧失为+0.09mm(SD:0.32mm;P=0.84)。结论: 分析得到的数据发现,牙槽骨高度的变化与种植设计或是牙龈生物型并无直接相关性。然而在选择种植设计之前,评价软组织的厚度是有利的,其中BL种植设计更能获得自然的外形。为实现以上评价目的,TRAN法是最快速、简易的方法。  相似文献   
90.
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