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51.
Genetic instability in superficial bladder cancer and adjacent mucosa: an interphase cytogenetic study 总被引:5,自引:0,他引:5
Cianciulli AM Leonardo C Guadagni F Marzano R Iori F De Nunzio C Franco G Merola R Laurenti C 《Human pathology》2003,34(3):214-221
A systematic analysis of both tumors and the surrounding urothelium to help identify what lies behind the mechanism of multifocal tumor development has not yet been performed. In this study we investigated chromosome 1, 7, 9, and 17 aneusomy in 25 superficial papillary carcinomas and in 51 tissue samples taken from sites of macroscopically uninvolved urothelium surrounding the tumors, using the fluorescence in situ hybridization method. Our data demonstrated a close genetic relationship between all examined tumors and normal-appearing mucosa. Numeric aberrations of chromosomes 1, 7, 9, and 17 were found to exhibit similar patterns in all analyzed specimens, although with different frequencies. 相似文献
52.
Brunetti-Pierri N Andreucci MV Tuzzi R Vega GR Gray G McKeown C Ballabio A Andria G Meroni G Parenti G 《American journal of medical genetics. Part A》2003,(2):164-168
Partial trisomy of the long arm of chromosome 10 is a well-defined but rare syndrome. Clinical features of this chromosomopathy are a distinctive dysmorphic appearance, developmental delay, growth retardation, and in some cases, abnormalities of the extremities and renal, cardiac and ocular anomalies. This report describes a neonate with symmetric growth retardation and multiple dysmorphic features, in whom chromosomal analysis revealed a partial trisomy of chromosome 10q with a monosomy of the 13q34 region. The phenotype shares many common features with previously published cases. In addition to the typical features, our case also shows renal hypoplasia with early renal insufficiency and some genital anomalies. 相似文献
53.
Leal Filho MB Morandin RC de Almeida AR Cambiucci EC Borges G Gontijo JA Metze K 《Neuroscience letters》2005,373(2):165-170
There are reports describing both provocation and inhibition of neurogenic pulmonary edema by anesthetic drugs. Therefore, we compared the effect of two types of anesthesia on the formation of neurogenic pulmonary edema in rats with balloon-induced acute spinal cord injury. Animals with sham procedure (group 1) were anesthesized by intraperitoneal sodium pentobarbital. In the experimental groups, rats were submitted to acute spinal cord lesion by insufflations of a balloon in the epidural space at T8 for 1 min (group 3 under i.p. sodium pentobarbital and group 2 under i.p. xylazine-ketamine anesthesia). In rats with pentobarbital anesthesia, systolic blood pressure doubled the baseline value during compression, whereas this effect was less pronounced in the ketamine-xylazine group. The pulmonary index (100 x wet lung weight/body weight) was 0.395 (+/-0.018) in sham-operated rats, rose to 0.499 (+/-0.060) in group 2, and was maximum under pentobarbital anesthesia (0.639+/-0.14; p=0.0018). Histologic examination of the spinal cord showed parenchymal ruptures and acute hemorrhage. Comparison of the pulmonary index with histologic slides of lung parenchyma revealed that relevant intra-alveolar edema occurred only for index values above 0.55. On electron microscopy, endothelial alterations, and damage of the alveolar lining cells were found. Our study indicates that neurogenic pulmonary edema caused by spinal cord injury is less pronounced in rats under xylazine-ketamine anesthesia, when compared with pentobarbital. 相似文献
54.
Endogenous levels of mRNA for IFNs and IFN-related genes in hepatic biopsies of chronic HCV-infected and non-alcoholic steatohepatitis patients 总被引:3,自引:0,他引:3
Abbate I Romano M Longo R Cappiello G Lo Iacono O Di Marco V Paparella C Spano A Capobianchi MR 《Journal of medical virology》2003,70(4):581-587
To investigate the intra-hepatic activation of the IFN system in patients affected by chronic HCV-infection in comparison with that observed in a non-infectious liver disease such as non-alcoholic steatohepatitis, we measured the liver steady state mRNA levels of interferon-alpha, interferon-beta and interferon-gamma as well as of IFN-related genes (IFNAR-1, STAT1alpha, PKR, 2-5 AS, IRF-1, ICE and IL-18). In HCV-infected subjects, possible correlations of these parameters with viral load and liver injury were also analyzed. Twenty-four chronic untreated HCV-infected subjects and seven patients with non-alcoholic steatohepatitis were enrolled in the study. Liver biopsies were graded according to Knodell scores. Intra-hepatic mRNA levels of IFNs and related genes were assessed by semi-quantitative RT-PCR. In comparison with non-alcoholic steatohepatitis, in HCV-infected subjects IFN-alpha and -beta mRNA levels were significantly lower, whereas IFN-gamma, IFNAR-1, STAT1alpha IRF-1, and IL-18 mRNA were upregulated. Moreover, IFN-gamma mRNA steady state levels were correlated positively with those of IFNAR-1, IRF-1, and IL-18, suggesting a coordinated induction of these genes. Although plasma viral load was correlated inversely with IL-18-specific mRNA, viral load was not related to liver injury. IFN-gamma and IRF-1 mRNA levels were correlated positively with ALT, but not with the grading or staging. Conversely, IFN-alpha and -beta mRNA levels were higher in livers with lower staging scores. These findings support the hypothesis that in chronic HCV infection there is an imbalance between an upregulated IFN-gamma system and a downregulated IFN-alpha and -beta system, probably due to a mixed effect exerted by HCV-specific and inflammatory non-specific factors. 相似文献
55.
Cytokines are important regulators of materno-fetal immunotolerance in mammals. They act within an intricate network, in which the balance among different cytokines contributes to the success of reproductive processes. Despite numerous studies, however, the role of cytokines at the materno-fetal interface remains largely unknown. Interleukin-1 (IL-1) is a proinflammatory cytokine with many functions in the immune system and in defence against infections. There have been very many studies of the presence and role of IL-1 in human and murine reproduction. Although studies on mammals have shown that IL-1 is an essential mediator in embryo implantation and establishment of pregnancy, mice that are transgenic for most components of the IL-1 family breed normally, suggesting that IL-1 acts in concert with other cytokines at the materno-fetal interface. We recently showed that IL-1 is also expressed by the placenta of non-mammalian vertebrates, including some squamate reptiles and elasmobranch fishes. The expression of IL-1 at the materno-fetal interface in the phylogenetically oldest extant placental vertebrates suggests that IL-1 is a fundamental regulator of materno-fetal relationships. 相似文献
56.
Cusin C Serretti A Lattuada E Lilli R Lorenzi C Smeraldi E 《American journal of medical genetics》2002,114(4):380-390
The aim of our study was to investigate a possible influence of monoamine oxydase A (MAO-A), catechol-O-methyltransferase (COMT), serotonin receptor 2A (5-HT2A), dopamine receptor D2 (DRD2), and dopamine receptor D4 (DRD4) gene variants on timing of recurrence in mood disorders. Gene variants were determined using PCR-based techniques in 550 inpatients affected by recurrent mood disorders (major depressives: n = 212; bipolars: n = 338), rapid cycling mood disorder (n = 81), and 663 controls. We investigated possible genetic influences by comparing illness time course of subjects subdivided according to genotype using multivariate analysis of variance (MANOVA). We could not observe a significantly different time course. No demographic and clinical variables such as sex, age or polarity of onset, presence of psychotic features, genetic loading, or education level influenced the observed results. Our results suggest that MAO-A, COMT, 5-HT2A, DRD2, and DRD4 gene variants are not involved in susceptibility toward different time courses in mood disorders. 相似文献
57.
Candida albicans expresses a focal adhesion kinase-like protein that undergoes increased tyrosine phosphorylation upon yeast cell adhesion to vitronectin and the EA.hy 926 human endothelial cell line 下载免费PDF全文
Santoni G Lucciarini R Amantini C Jacobelli J Spreghini E Ballarini P Piccoli M Gismondi A 《Infection and immunity》2002,70(7):3804-3815
The signaling pathways triggered by adherence of Candida albicans to the host cells or extracellular matrix are poorly understood. We provide here evidence in C. albicans yeasts of a p105 focal adhesion kinase (Fak)-like protein (that we termed CaFak), antigenically related to the vertebrate p125Fak, and its involvement in integrin-like-mediated fungus adhesion to vitronectin (VN) and EA.hy 926 human endothelial cell line. Biochemical analysis with different anti-chicken Fak antibodies identified CaFak as a 105-kDa protein and immunofluorescence and cytofluorimetric analysis on permeabilized cells specifically stain C. albicans yeasts; moreover, confocal microscopy evidences CaFak as a cytosolic protein that colocalizes on the membrane with the integrin-like VN receptors upon yeast adhesion to VN. The protein tyrosine kinase (PTK) inhibitors genistein and herbimycin A strongly inhibited C. albicans yeast adhesion to VN and EA.hy 926 endothelial cells. Moreover, engagement of alpha v beta 3 and alpha v beta 5 integrin-like on C. albicans either by specific monoclonal antibodies or upon adhesion to VN or EA.hy 926 endothelial cells stimulates CaFak tyrosine phosphorylation that is blocked by PTK inhibitor. A role for CaFak in C. albicans yeast adhesion was also supported by the failure of VN to stimulate its tyrosine phosphorylation in a C. albicans mutant showing normal levels of CaFak and VNR-like integrins but displaying reduced adhesiveness to VN and EA.hy 926 endothelial cells. Our results suggest that C. albicans Fak-like protein is involved in the control of yeast cell adhesion to VN and endothelial cells. 相似文献
58.
Oniscu A James RM Morris RG Bader S Malcomson RD Harrison DJ 《The Journal of pathology》2004,203(4):909-917
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
59.
Joseph H Flaherty Diana A Fabacher Roberta Miller Andrea Fox Jeremy Boal 《Academic medicine》2002,77(4):336-343
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
60.
Wade NA Zielinski MA Butsashvili M McNutt LA Warren BL Glaros R Cheku B Pulver W Pass K Fox K Novello AC Birkhead GS 《Journal of acquired immune deficiency syndromes (1999)》2004,36(5):1075-1082
BACKGROUND: Perinatal HIV transmission has declined significantly in New York State (NYS) since implementation of a 3-part regimen of zidovudine prophylaxis in the antenatal, intrapartum, and newborn periods. This study describes the factors associated with perinatal transmission in NYS from 1997 to 2000, the first 4 years of NYS's comprehensive program in which all HIV-exposed newborns were identified through universal HIV testing of newborns. METHODS: This population-based observational study included all HIV-exposed newborns whose infection status was known and their mothers identified in NYS through the universal Newborn HIV Screening Program (NSP) from February 1997 to December 2000. Antepartum, intrapartum, newborn, and pediatric medical records of HIV-positive mothers/infants were reviewed for history of prenatal care, antiretroviral therapy (ART), and infant infection status. Risks associated with perinatal HIV transmission were examined. RESULTS: Perinatal HIV transmission declined significantly from 11.0% in 1997 to 3.7% in 2000 (P < 0.05). Prenatal ART was associated with a decline in perinatal HIV transmission both for monotherapy (5.8%, relative risk [RR] = 0.3, 95% confidence interval: 0.2%-0.5%) and combination therapy [2.4%, RR = 0.1, 95% confidence interval: 0.1%-0.2%) compared with no prenatal antiretroviral prophylaxis (P < 0.05). CONCLUSIONS: Public health policies to improve access to care for pregnant women and advances in clinical care, including receipt of appropriate preventive therapies, have contributed to declines in perinatal HIV transmission in NYS. 相似文献