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41.
Expression of Sonic hedgehog pathway genes is altered in colonic neoplasia   总被引:8,自引:0,他引:8  
The Hedgehog (Hh) signalling pathway is crucial for normal development and patterning of numerous human organs including the gut. Hh proteins are also expressed during gastric gland development and gastric epithelial differentiation in adults. Recently, dysregulation of these developmentally important genes has been implicated in cancer, leading to the present study of the expression of Hh signalling proteins in colon cancer. In this study, normal colon and colonic lesions (hyperplastic polyp, adenoma, and colonic adenocarcinoma) were examined by immunohistochemistry using antibodies against Hh signalling molecules: the secreted protein Sonic hedgehog (SHH), its receptor Patched (PTCH), and the PTCH-associated transmembrane protein Smoothened (SMOH). The study shows that Hh signalling pathway members are expressed in normal colonic epithelium. SHH was expressed at the top of the crypts and in a few basally located cells, while PTCH was detected in the neuroendocrine cells and SMOH at the brush border of superficial epithelium. RT-PCR analysis of laser-microdissected crypts from normal human colon confirmed that mRNAs encoding these proteins were expressed in colonic epithelium. Expression of SHH, PTCH, and SMOH was up-regulated in hyperplastic polyps, adenomas, and adenocarcinomas of the colon, and SHH expression correlated with increased expression of the proliferation marker Ki-67 in all lesions examined. To address whether the Hh signalling pathway is functional in the gut, the effect of Shh on epithelial cells in vitro was explored by treating primary murine colonocytes with either Shh peptide or neutralizing anti-Shh antibody. The proportion of cells in the S-phase was assessed by bromodeoxyuridine (BrdU) incorporation. It was found that exogenous Shh promotes cell proliferation in colonocytes, while anti-Shh inhibits proliferation, suggesting that Shh is required during proliferation of epithelial cells in vitro. It is suggested that SHH is required during epithelial proliferation in the colon and that there is a possible role for Hh signalling in epithelial colon tumour progression in vivo.  相似文献   
42.
PURPOSE: To report attitudinal changes of medical students from five medical schools rotating through a home care program, and to determine which of the program characteristics influenced attitudes the most. METHOD: A survey instrument covering four home care domains (general attitudes, home-based therapies, home care training, and time and reimbursement) was designed and validated by the five schools involved. Using pre- and post-rotation scores, analyses were done to evaluate for attitudinal changes within and among schools. The programs had similar basic characteristics (home visits, attending physicians' involvement, didactics), but had differing degrees of these components. RESULTS: Significant improvements in attitude scores were found in three domains: general attitudes, homebased therapies, and home care training. For time and reimbursement, only three schools improved significantly between pre- and post-rotation scores. Among the five schools, there were significant differences in the homebased therapies and home care training domains (p <.05), and in the time and reimbursement domain the difference approached significance (p =.06). None of the students' characteristics but all of the programs' characteristics significantly correlated with changes in total scores. In the first multiple regression model, educational level (third year instead of fourth) was the only independent predictor of change in score, (adjusted r(2) =.14). In Model 2, the strongest predictor was "contact with physician-program director," followed by "number of visits" and "physician-precepted visits" (r(2) =.23). CONCLUSION: Educational home care programs of varying intensities can positively affect medical students' attitudes towards home care. At least three program characteristics, (the physician-program director, number of visits, and physician-precepted home visits), are important parts of a successful program.  相似文献   
43.
The occurrence of stent post deformity was investigated in 38 consecutive, polypropylene flexible-stented Hancock porcine bioprostheses (PB) recovered from the mitral position because of early postoperative death or late tissue failure. The degree of deformity was assessed for each explant by calculating the triangular area obtained by projecting the apex of the stent posts on a plane and comparing it with the same area calculated for unimplanted PBs of comparable size. A significant stent deformity (reduction of the triangular area greater than 40%) was observed only in 6 PBs explanted because of tissue failure after a mean function time of 69.6 +/- 28 months. In these PBs, scanning electron microscopy of the bare surface of the stent at the point of maximal flexion showed cracks 0.7-1 microns large, which represent the morphological substrate of the so-called "creep" of polypropylene. Inward stent post bending may occur after implantation in mitral PBs and when severe, it corresponds to a definite ultrastructural plastic deformity of polypropylene.  相似文献   
44.
Duodenal ulcer     
In 1958 the Yale freshman class gave blood samples as part of a study intended to determine the predictive value of plasma pepsinogen (PP) for the subsequent development of duodenal ulcer (DU). We report a long-term follow-up of this cohort. A selfadministered questionnaire designed to ascertain information about the development of peptic ulcers, and the presence of risk factors was mailed to 861 subjects with active addresses. A second questionnaire was mailed to each respondent's physician(s) to verify the diagnosis of DU. Completed questionnaires were returned, after three mailings, by 604 (70%) of the subjects. They reported 18 documented DUs, 15 since 1958, for an incidence of 1.1/1000 person years. Only smoking (P<0.05) and undergraduate physical inactivity (P<0.01) were identified as risk factors for DU. Family history; blood type; blood antigen secretor status; ingestion of coffee, alcohol, milk, salicylates, soda, or tea; and COPD were not identified as risk factors for DU. Patients with DU had higher mean PP values than those who did not (391.6±99.6 vs 346.6±106.7, mean ±sd) but this was not statistically significant (P>0.05). The predictive value of an elevated PP(>450) for the development of DU was 7.9%, but a low or normal PP predicted the absence of a DU in 97.5% of subjects over a 22-year span. We conclude that in a selected population followed for 22 years there is a low incidence of DU, supporting the general belief that duodenal ulcer is declining, that smoking and undergraduate physical inactivity are risk factors for duodenal ulcer, and that a low or normal PP may be useful as a predictor for a low susceptibility to duodenal ulcer disease.Dr. J. Chuong acknowledges the support of the Robert Wood Johnson Clinical Scholar Program, and the Daland Fellowship in Clinical Medicine of the American Philosophical Society.  相似文献   
45.
Magnesium (Mg2+) deficiency is probably the most underestimated electrolyte imbalance in Western countries. It is frequent in obese patients, subjects with type-2 diabetes and metabolic syndrome, both in adulthood and in childhood. This narrative review aims to offer insights into the pathophysiological mechanisms linking Mg2+ deficiency with obesity and the risk of developing metabolic syndrome and type 2 diabetes. Literature highlights critical issues about the treatment of Mg2+ deficiency, such as the lack of a clear definition of Mg2+ nutritional status, the use of different Mg2+ salts and dosage and the different duration of the Mg2+ supplementation. Despite the lack of agreement, an appropriate dietary pattern, including the right intake of Mg2+, improves metabolic syndrome by reducing blood pressure, hyperglycemia, and hypertriglyceridemia. This occurs through the modulation of gene expression and proteomic profile as well as through a positive influence on the composition of the intestinal microbiota and the metabolism of vitamins B1 and D.  相似文献   
46.
Varicocele is an age-related disease with no current medical treatments positively impacting infertility. Toll-like receptor 4 (TLR4) expression is present in normal testis with an involvement in the immunological reactions. The role of peroxisome proliferator-activated receptor-α (PPAR-α), a nuclear receptor, in fertility is still unclear. N-Palmitoylethanolamide (PEA), an emerging nutraceutical compound present in plants and animal foods, is an endogenous PPAR-α agonist with well-demonstrated anti-inflammatory and analgesics characteristics. In this model of mice varicocele, PPAR-α and TLR4 receptors’ roles were investigated through the administration of ultra-micronized PEA (PEA-um). Male wild-type (WT), PPAR-α knockout (KO), and TLR4 KO mice were used. A group underwent sham operation and administration of vehicle or PEA-um (10 mg/kg i.p.) for 21 days. Another group (WT, PPAR-α KO, and TLR4 KO) underwent surgical varicocele and was treated with vehicle or PEA-um (10 mg/kg i.p.) for 21 days. At the end of treatments, all animals were euthanized. Both operated and contralateral testes were processed for histological and morphometric assessment, for PPAR-α, TLR4, occludin, and claudin-11 immunohistochemistry and for PPAR-α, TLR4, transforming growth factor-beta3 (TGF-β3), phospho-extracellular signal-Regulated-Kinase (p-ERK) 1/2, and nucleotide-binding oligomerization domain-like receptor (NLR) family pyrin domain-containing 3 (NLRP3) Western blot analysis. Collectively, our data showed that administration of PEA-um revealed a key role of PPAR-α and TLR4 in varicocele pathophysiology, unmasking new nutraceutical therapeutic targets for future varicocele research and supporting surgical management of male infertility.  相似文献   
47.
Background: Polydatin is a stilbenoid with important antioxidant, anti-inflammatory, and immunomodulating properties. The aim of this study was to assess the anti-inflammatory preventive effect of polydatin in the mouse model of acute arthritis induced by calcium pyrophosphate (CPP) crystals. Methods: Acute arthritis was induced by the injection of a suspension of sterile CPP crystals into the ankle joint of Balb/c mice. Animals were randomized to receive polydatin or colchicine (the control drug) according to a prophylactic and a therapeutic protocol. The primary outcome was the variation of ankle swelling obtained after crystal injection and treatment, while histological parameters such as leukocyte infiltration, IL-1ß and CXCL1 levels and tissue expression were considered as secondary outcomes. Results: Prophylactic treatment with PD significantly diminished ankle swelling after 48 h from crystal injection. Secondary outcomes such as leukocyte infiltration, necrosis, edema, and synovitis were also decreased. PD caused a reduction in circulating levels of IL-1ß and CXCL1, as well as their tissue expression. By contrast, the therapeutic administration of PD did not have any beneficial effect. Conclusions: PD can effectively prevent acute inflammatory response to crystals in the mouse model of CPP crystal-induced arthritis. These results suggest that this bioactive compound might be used in the prevention of crystal-induced acute attacks in humans.  相似文献   
48.
49.
Elderly women exhibit a high risk of type 2 diabetes (T2D), but no definitive data exist about the possible role of postmenopausal increases in visceral adiposity, the loss of lean body mass, or decreases in the sum of the lean mass of arms and legs (appendicular skeletal muscle mass (ASMM)). This retrospective, longitudinal study investigated whether body composition (bioelectrical impedance analysis) predicted the development of impaired fasting glucose (IFG) or T2D in a cohort of 159 elderly women (age: 71 ± 5 years, follow-up: 94 months) from southern Italy (Clinical Nutrition and Geriatric Units of the “Mater Domini” University Hospital in Catanzaro, Calabria region, and the “P. Giaccone ”University Hospital in Palermo, Sicily region). Sarcopenia was defined in a subgroup of 128 women according to the EWGSOP criteria as the presence of low muscle strength (handgrip strength <16 kg) plus low muscle mass (reported as appendicular skeletal muscle mass <15 kg). Participants with a low ASMM had a higher IFG/T2D incidence than those with a normal ASMM (17% vs. 6%, p-adjusted = 0.044); this finding was independent of BMI, fat mass, waist circumference, and habitual fat intake (OR = 3.81, p = 0.034). A higher incidence of IFG/T2D was observed in the subgroup with sarcopenia than those without sarcopenia (33% vs. 7%, p-adjusted = 0.005) independent of BMI and fat mass (OR = 6.75, p = 0.007). In conclusion, this study demonstrates that elderly women with low ASMM had a higher probability of developing IFG/T2D. Further studies are needed to confirm these results in men and in other age groups.  相似文献   
50.
Lasers in Medical Science - Ultraviolet radiation (UVR) is the major etiologic agent of cutaneous photoaging, and different strategies are used to prevent and treat this condition. The...  相似文献   
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