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51.
Introduction  The objective of this study was to determine the expression levels of metallothionein (MT) and p53 protein, recognized neoplastic transformation markers, in pancreatic serous cystadenomas (SCA) and adenomocarcinomas. Materials and Methods  Neoplastic pancreatic tissue was taken from 20 patients with diagnosed benign (SCA: 5 cases) or malignant tumors (adenomocarcinomas: 15 cases) and control pancreatic tissue from healthy persons who had died in car accidents. Sections were stained with hematoxylin-eosin. Immunohistochemical localization of MT and p53 protein was carried out by LSAB2-HRP using specific antibodies against MT and p53. Results  Metallothionein expression was observed only in the epithelial cells of the neoplastic tissue of SCAs. MT expression in the cystadenomas was weaker than in the healthy pancreatic tissue. No tissue was found with p53 protein expression. In the adenomocarcinomas, positive staining for MT was observed in 67% and p53 was positive in the carcinoma cells. Conclusion  The weak MT expression and lack of p53 protein expression in pancreatic SCAs confirms the lack of local invasive potential of the neoplastic lesion. Increased expressions of MT and p53 were observed in the less differentiated tumors. Thus the expression of MT may be a potential prognostic marker for tumors.  相似文献   
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BACKGROUND: Factors influencing the depletion of CD4(+) cells and the restoration of CD4(+) cells after antiretroviral therapy are not completely understood. Recently, attention has been paid to interleukin (IL)-7 and its receptor (CD127). We analyzed the influence of T cell activation and of suppression of viremia with antiretroviral therapy on this system, as well as its role in CD4(+) cell restoration after long-term antiretroviral therapy. METHODS: IL-7 levels and CD127 expression on several subsets of CD4(+) and CD8(+) T lymphocytes and the activation status (CD38) of these cells were examined at baseline and during 24 months of complete viral suppression under highly active antiretroviral therapy (HAART). RESULTS: A total of 42 individuals with human immunodeficiency virus (HIV) infection and 10 age-matched, uninfected control subjects were examined. Before HAART, IL-7 levels were increased and CD127 expression was decreased. Down-regulation of CD127 was mainly associated with T cell activation and reverted only partially after suppression of detectable plasma HIV RNA with HAART. In a multivariate analysis, CD127 expression on CD8(+) T cells was the main determinant of the extent of CD4(+) cell gains after successful HAART. CONCLUSIONS: The IL-7-CD127 system is impaired in HIV-infected patients. CD127 down-regulation is associated with T cell activation and with CD4(+) cell restoration after HAART.  相似文献   
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55.

Objective

To evaluate the effect of periodontal treatment on gingival overgrowth in a group of renal transplant patients.

Subjects and Methods

Twenty-five renal transplant recipients receiving immunosuppressive therapy with cyclosporine A (CsA) were randomly assigned to 2 groups. Group 1 (n = 15) included patients who had been specifically referred to a dental clinic to prevent gingival overgrowth and were given full periodontal therapy. Group 2 (n = 10) was comprised of patients who did not receive any professional periodontal cleaning. Patients from both groups were examined to determine their periodontal status before and after 3, 6 and 12 months in terms of their plaque index, gingival index and gingival overgrowth. During the examination, their overall health was stable.

Results

For group 1, the scores were 1.89 (baseline), 0.98 (6 months) and 0.56 (12 months), and hence there were significant reductions (p = 0.0001). The gingival indices were 1.71 (baseline), 0.76 (6 months) and 0.35 (12 months), and the reductions were also significant (p = 0.0001). A significant association was observed between poor oral hygiene and the degree of gingival overgrowth. The 1-year post-treatment follow-up showed that patients in group 1 did not develop gingival overgrowth due to the use of CsA as group 2 did without prior periodontal therapy.

Conclusion

Oral hygiene status was the most important variable related to the development and degree of gingival overgrowth due to the use of CsA.Key Words: Gingival overgrowth, Periodontal treatment, Cyclosporine  相似文献   
56.
The aim of our study was an estimation of thyroid structure and function in 37 patients with Turner syndrome aged from 19 to 60 years and in control group of healthy women. In each case the following studies were performed: cytogenetic examination, thyroid ultrasonography, serum total and free thyroid hormones, TSH, thyroglobulin (Tg), thyroid hormones binding globulin (TBG), antithyroglobulin and antithyroperoxidase antibodies (anti-Tg and anti-TPO) levels. In Turner syndrome ultrasonographic volume of the thyroid was significantly lower than in control group (11.03 vs 16.98 cm3). Abnormalities of thyroid function were found in 8 (22%) studied cases (subclinical primary hypothyroidism in 16%, full-clinical primary hypothyroidism in 3% and hyperthyroidism in course of Graves disease in 3%). Serum elevated antithyroid antibodies were present in 62% cases of Turner syndrome and were significantly higher than in control group (16%). In Turner syndrome thyroid diseases are more frequent than in healthy population. Every patient with Turner syndrome needs routine diagnostics of the thyroid structure and function.  相似文献   
57.
BackgroundPostoperative ileus is the main determinant of the length of hospital stay after colorectal surgery. Our objective was to analyze modifiable factors, including polyethylene glycol administration, associated with the return of bowel function.MethodsA retrospective review of all patients who underwent elective open partial colectomy from 2004 to 2006 at a single institution.ResultsThe time to the first bowel movement with and without oral intake within 48 hours postoperatively was 76 hours versus 134 hours (P < .001); with and without polyethylene glycol administration it was 73 hours versus 94 hours (P = .001); and with and without frequent ambulation it was 78 hours versus 95 hours (P = .012). With postoperative nasogastric tube drainage, the time to the first bowel movement was 22 hours longer (P = .002).ConclusionsThese data confirm previous findings supporting no nasogastric tube drainage, early feeding, and frequent ambulation after colorectal surgery. Additionally, our data suggest a strong association (P = .001) between the use of polyethylene glycol and the early return of bowel function.  相似文献   
58.
Ovarian cancer is characterized by the higher mortality among gynecological cancers. In results of MDR development during chemotherapy cancer cells become resistant to further treatment. Microarray techniques can provide information about MDR development at gene expression level. ABC and SLC transporters are most important proteins responsible for this phenomenon. In this study changes of ABC and SLC genes expression pattern in drugs resistant sublines of the A2780 ovarian cancer cell line were demonstrated. The cytostatic resistant sublines were generated by culture of A2780 cell line with an increasing concentration of the indicated drugs. As screening methods, we used Affymetrix U219 Human Genome microarrays. Independent t-tests were used to determinate statistical significances of results. Genes that expression levels were higher than assumed threshold (upregulated above threefold and downregulated under −3 fold) were visualized using scatter plot method, selected and listed in table. Between the ABC genes increased expression of seven genes and decreased expression of three genes were observed. Expression of two genes was increased or decreased depending on the cell line. We observed significant (more than tenfold) increase in expression of four ABC genes: ABCA8, ABCB1, ABCB4 and ABCG2 and decreased expression of ABCA3 gene. We also observed changes in expression of 32 SLC genes. Between them we observe increased expression of 17 genes and decreased expression of 15 genes. Expression of four genes was increased or decreased dependent on cell line. The expression of nine SLC genes increased or decreased very significantly (more than tenfold). Five genes were significantly upregulated: SLC2A9, SLC16A3, SLC16A14, SLC38A4 and SLC39A8. Four additional genes were significantly downregulated: SLC2A14, SLC6A15, SLC8A1 and SLC27A2. Expression profiles of these genes give strong arguments for assumption of correlation between expression of ABC and SLC genes and drug resistance phenomenon. Identifying correlations between specific drug transporters and cytostatic drug resistance will require further investigation.  相似文献   
59.
By using immunofluorescent staining we were able to characterize the age-related changes in the macromolecules making up the extracellular matrix of the lamina cribrosa of the human optic nerve head. As the cores of the cribriform plates enlarged with age, there were age-related increases in the apparent density of collagen types I and III and elastin that constituted the connective tissue support of the nerve bundles. Collagen type IV coated the cribriform plates as basement membranes and was also present within the cores as a fine filamentous network, which increased in density with age as the cribriform plates expanded. As this tissue ages, individual differences leading to more or less of a particular macromolecule of the extracellular matrix may alter the support function of the lamina cribrosa and influence the degeneration of the optic nerve associated with glaucoma.  相似文献   
60.
The aim of the study was to evaluate alterations in exocrine cell mitochondria of the rat pancreas after lead acetate intoxication. The experiment used 45 rats divided into 2 experimental groups receiving lead acetate to drink, of lead concentration 50 and 500 mg/dm3 (ppm), and a control group given tap water. The animals from the experimental group were decapitated after 2, 4, 6 and 8 weeks, 5 rats from the control group after 8 weeks of the experiment. Rats from experimental groups decapitated after 8 weeks had lead administration stopped after six weeks and then, for two weeks tap water was given. Pancreatic sections were examined with biochemical methods for the activity of cytochrome oxidase and succinic dehydrogenase. Ultrastructural and morphometric examinations were also performed. It was demonstrated that: a) exocrine cell mitochondria are particularly predisposed to lead effect, b) intoxication of rats with lower lead doses (50 ppm) causes reversible adaptative or compensatory changes in these organelles, c) intoxication of rats with higher lead doses (500 ppm) induces irreversible ultrastructural alterations in numerous mitochondria, including damage to inner and to outer mitochondrial membranes, d) structural changes in the mitochondria in the course of lead intoxication are the morphological expression of the impairment of metabolic processes, associated with the inhibited activity of the respiratory enzymes: succinic dehydrogenase and cytochrome oxidase.  相似文献   
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