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21.
Paolo Leoncini Marcella Cintorino Carla Vindigni Lorenzo Leoncini Doretta Armellini Massimo Bugnoli Omar Skalli Giulio Gabbiani 《Virchows Archiv : an international journal of pathology》1988,412(4):329-337
Summary We have evaluated by means of immunocytochemistry the distribution of various cytoskeletal and contractile proteins (cytokeratins, vimentin, desmin and -smooth muscle actin) in 23 salivary or lacrimal gland primary tumours (15 pleomorphic adenomas and 8 carcinomas in pleomorphic adenoma), one third of which contained areas of normal gland. Normal epithelial luminal cells were stained by cytokeratin antibodies with a general specificity, while myoepithelial cells were selectively stained by a monoclonal antibody (SK2-27) reacting in immunoblots with cytokeratin polypeptides 14, 16 and 17, according to the classification of Moll et al. (1982) and by an antibody directed against -smooth muscle actin (Skalli et al. 1986). In pleomorphic adenomas, both epithelial and myoepithelial cells displayed typical topographic distributions; moreover, myoepithelial cells showed two distinct cytoskeletal phenotypes. These findings could account in part for the heterogeneity of aspects observed in this tumour. In carcinomas, malignant cells were always positive to cytokeratin antibodies with general specificity and myoepithelial cells were absent as judged by anticytokeratin SK2-27 and anti--smooth muscle actin immunostainings. However, interestingly, there was in all cases a strong positivity for -smooth muscle actin in stromal cells, similarly to what has previously been described for mammary carcinoma (Skalli et al. 1986). Our findings may be useful for the interpretation of the histogenesis of salivary and lacrimal tumour and stromal cells. 相似文献
22.
Rat hepatic lipocytes express smooth muscle actin upon activation in vivo and in culture. 总被引:25,自引:0,他引:25
D C Rockey J K Boyles G Gabbiani S L Friedman 《Journal of submicroscopic cytology and pathology》1992,24(2):193-203
Myofibroblasts are mesenchymal cells that are prominent in liver injury. The origin of myofibroblasts in liver is debated, although morphologic evidence to date has suggested that these cells are derived from lipocytes (fat-storing cells, Ito cells). In the present study, we have utilized smooth muscle alpha actin antibody--a marker of myofibroblasts and smooth muscle cells--to study lipocytes in situ in normal and fibrotic rat liver as well as during their 'activation' in culture. Dual immunofluorescence studies on tissue sections from normal liver identified lipocytes as perisinusoidal desmin-positive, smooth muscle alpha actin-negative cells. In bile duct obstructed fibrotic liver, desmin-positive cells were numerous in areas of fibrosis and these cells also exhibited smooth muscle alpha actin. In carbon tetrachloride-induced fibrosis, cells expressing both desmin and smooth muscle alpha actin were present in fibrotic bands and in regenerating nodules. These results suggested that lipocytes had acquired characteristics of myofibroblasts during liver injury. To further address this issue we examined lipocytes immediately after isolation and also in primary culture. In freshly isolated lipocytes from normal liver, smooth muscle alpha actin was absent. In contrast, freshly isolated lipocytes from CCl4-treated animals expressed this smooth muscle marker immediately after isolation. In primary culture on plastic, lipocytes from normal liver began to express smooth muscle alpha actin coincident with culture-induced activation; at 14 days, smooth muscle alpha actin was identified in all cells. Electron microscopy demonstrated a highly developed array of microfilament bundles characteristic of actin filaments. Immunoblot of culture-activated lipocytes using the smooth muscle alpha actin antibody demonstrated the expected 42 kD protein (corresponding to the molecular size of smooth muscle alpha actin). Although smooth muscle alpha actin was readily detectable in culture-activated cells, it was not expressed in cells in which a quiescent phenotype was preserved by maintenance in culture on a laminin-rich gel. These findings demonstrate that the acquisition by lipocytes of a smooth muscle marker accompanies their 'activation', and are consistent with the hypothesis that lipocytes transform to myofibroblasts during liver injury. 相似文献
23.
Myofibroblasts from diverse pathologic settings are heterogeneous in their content of actin isoforms and intermediate filament proteins 总被引:31,自引:0,他引:31
O Skalli W Schürch T Seemayer R Lagacé D Montandon B Pittet G Gabbiani 《Laboratory investigation; a journal of technical methods and pathology》1989,60(2):275-285
We examined by immunofluorescence the distribution of vimentin, desmin, alpha-smooth muscle actin and alpha-sarcomeric actin in normal human soft tissues and in pathologic tissues containing myofibroblasts, including normally healing granulation tissue, hypertrophic scar, and fibromatosis. The pattern of actin isoforms was also documented biochemically by two-dimensional gel electrophoresis. Fibroblastic and/or myofibroblastic cells in each setting always expressed vimentin and never alpha-sarcomeric actin. Moreover, these cells showed an heterogeneous cytoskeletal composition which defined four phenotypes: (a) cells expressing only vimentin; (b) cells expressing vimentin, alpha-smooth muscle actin and desmin; (c) cells expressing vimentin and alpha-smooth muscle actin; and (d) cells expressing vimentin and desmin. Given this, two groups of lesions are distinguished: the first contains only vimentin cells and consists of normally healing granulation tissue, eschars and normally healed scars; the second contains vimentin cells admixed with variable proportions of vimentin, alpha-smooth muscle actin and desmin, vimentin and alpha-smooth muscle actin, and vimentin and desmin cells and consists of hypertrophic scars and fibromatoses. Immunogold electron microscopy showed that alpha-smooth muscle actin was present in a proportion of cells with ultrastructural features of myofibroblasts. Our findings suggest that contrary to myofibroblasts of normally healing granulation tissue and normally healed scars, myofibroblasts of pathologic conditions characterized by chronic retraction express always immunochemical features indicative of smooth muscle differentiation. 相似文献
24.
Masi G Perugi G Toni C Millepiedi S Mucci M Bertini N Akiskal HS 《Journal of affective disorders》2004,78(3):175-183
BACKGROUND: Growing evidence documents the frequent co-morbidity between Obsessive Compulsive Disorder (OCD) and Bipolar Disorder (BP) in adults. The aim of the present study is to explore some clinical aspects of this interface in children and adolescents, as it appears in a setting of routine clinical practice. METHOD: The sample comprised 102 consecutively referred children and adolescents, both inpatients and outpatients, with BP, OCD or co-morbid BP-OCD during a 3-year period. The mean age was 14.2 (SD=3.2); 65 (63.7%) were males. Diagnoses and clinical features were collected by means of structured interview according to DSM-IV (DICA-R) and a rating scale for OCD (CY-BOCS). Clinical outcome was evaluated prospectively by means of clinical global impression (CGI) as part of routine clinical care, throughout the follow-up. RESULTS: Thirty-seven (36.3%) patients (21 males and 16 females) were diagnosed as BP, 35 (34.3%) patients (26 males and 9 females) were diagnosed as OCD and 30 (29.4%) patients (18 males and 12 females) were diagnosed as BP-OCD. BP II, was more frequent in the BP-OCD than in BP. When OCD was co-morbid with BP, age of onset was significantly earlier than in the 'pure' OCD patients. On the contrary, age of onset of BP was not affected by co-morbid OCD. According to CGI baseline scores, OCD patients were significantly less impaired than BP-OCD and BP patients, while the severity of the symptomatology was similar in the last two groups. Severity scores at the end of the follow-up were significantly higher in BP-OCD patients than in OCD patients. Patients with pure BP showed lower rates of panic disorder-agoraphobia than BP-OCD patients and higher rates of ADHD-conduct disorder. Pure OCD patients showed lower rates of ADHD and higher rates of Generalized Anxiety Disorder. The number of obsessions did not differentiate the two groups, whereas pure OCD patients showed significantly more compulsions. 'Other' obsessions-e.g., existential, philosophical, odd and/or superstitious-were significantly more frequent in BP-OCD than in pure OCD patients. Ordering compulsions were significantly more frequent in pure OCD patients. LIMITATIONS: Possible low reliability of children's and their parents' recall of past episodes of mental disorder. CONCLUSIONS: In a tertiary care center, co-morbidity between OCD and BP is a significant clinical problem affecting a large number of patients. The correct identification of OCD-bipolar co-morbidity has relevant clinical implications as far as other concomitant disorders, symptomatological features, course, complications, and treatment management and outcome are concerned. 相似文献
25.
Mastella Giulio Darstein Lars Raufhake Carsten Schneider Vera Corletto Anna Buiatti Alessandra Mller Alexander Schuessler-Hahn Franziska Gondert Markus Gerdes Heiko Martens Eimo 《Zeitschrift fur Gesundheitswissenschaften》2022,30(1):5-10
Journal of Public Health - Offshore wind energy is a fast growing market. Accordingly, a correspondingly large number of employees are working at the wind farms. Owing to the harsh operating... 相似文献
26.
Antonio Loforte Mariafrancesca Fiorentino Giacomo Murana Gregorio Gliozzi Giulio Giovanni Cavalli Carlo Mariani Sofia Martin Suarez Davide Pacini 《Transplantation proceedings》2021,53(1):311-317
BackgroundThe occurrence of early graft failure (EGF) after heart transplantation (Htx) often requires a mechanical circulatory support (MCS) therapy. The aims of our study were to identify risk factors of mechanically supported severe EGF and evaluate their impact on both early and late outcomes.MethodsBetween January 2000 and December 2019, 499 consecutive adult patients underwent Htx at our institution. Severe EGF was defined as the need for extracorporeal life support (ECLS) within 24 hours after surgery. All available recipient and donor variables were retrospectively analyzed.ResultsOverall, EGF occurred in 58 (11.6%) patients. Post-Htx peripheral or central ECLS was necessary in 32 (6.4%) cases. Independent predictors of severe EGF were, in the recipient group, preoperative transpulmonary gradient (TPG) >12 mm Hg (odds ratio [OR] 4.1, P = .013), preoperative inotropic score >10 (OR 7.3, P = .0001), and pre-Htx ECLS support (OR 5.2, P = .015), while in the donors, a Eurotransplant donor score ≥17 (OR 8.5, P = .005). The absence of EGF was related with a better survival at 1 year and 5 years (94% and 85%, respectively) compared with EGF requiring ECLS population (36% and 28% at 1 year and 5 years, respectively; P < .001). A five-year conditional survival rate did not differ significantly (85% no EGF vs 83% EGF requiring ECLS).ConclusionBoth donor and recipient factors may influence EGF occurrence. Post-Htx ECLS may impact negatively early; however, patients weaned from ECLS eventually benefit from such a rescue treatment with outcomes comparable with Htx patients who did not suffer EGF. 相似文献
27.
28.
de Palma L Santucci A Gigante A Di Giulio A Carloni S 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》1999,20(4):253-257
The analogies between plantar fibromatosis and Dupuytren's disease (palmar fibromatosis) are well known. The latter is clinically more frequent and has been the object of extensive immunohistochemical and ultrastructural studies, with a view to investigating its pathogenesis. By contrast, such data on plantar fibromatosis are quite scarce. A histochemical, immunohistochemical, and ultrastructural study was performed on nodule tissue from six patients who were subjected to total fasciectomy for plantar fibromatosis. The study of myofibroblasts revealed features suggestive of their fibroblastic origin and evidenced a cytoskeleton and an extracellular filamentous system that could enable myofibroblasts to generate and exert the intracellular forces that contribute to the contraction of the aponeurosis. These aspects are similar to those observed in Dupuytren's disease and seem to lend support to the theory that the two diseases are expressions of the same disorder. 相似文献
29.
Evaluation of vesico-urethral and sweating function in disorders presenting with parkinsonism 总被引:1,自引:0,他引:1
Milena De Marinis Guido Argenta Domenico Mele Antonio Carbone Giulio Baffigo Alessandro Agnoli 《Clinical autonomic research》1993,3(2):125-130
Investigation of vesico-urethral and sweating function was performed in twelve patients with classical idiopathic Parkinson's disease and ten patients with parkinsonism associated with features suggestive of more extensive involvement of the nervous system, as in the Shy—Drager syndrome. The urodynamic studies revealed detrusor hyperreflexia with reduction of maximal cystometric capacity in only one patient with Parkinson's disease (8%), but in nine patients with parkinsonism associated with other features (90%). Urethral sphincter electromyography did not indicate denervation in any patient of either group. Delayed or incomplete relaxation of the urethral sphincter during micturition was observed in seven patients with Parkinson's disease (58%) and in two patients of the other group (20%). Decreased sweating responses were found in both groups of patients when compared with control subjects. Hypohidrosis was more pronounced in parkinsonism associated with other features than in Parkinson's disease. Differences in sweating between the two sides of the body were observed in both groups of patients. Although there are differences in vesico-urethral and sweating function, they do not precisely differentiate between patients with classical Parkinson's disease and those with parkinsonism associated with features suggestive of more extensive involvement of the nervous system. 相似文献
30.
Dr. Carlo Merkel MD Angelo Gatta MD Marco Zoli MD Massimo Bolognesi MD Paolo Angeli MD Tiziana Iervese MD Giulio Marchesini MD Arturo Ruol MD 《Digestive diseases and sciences》1991,36(9):1197-1203
Seventy-eight patients with cirrhosis were prospectively followed for up to 20 months, on the average. At entry into the study, galactose elimination capacity, aminopyrine breath test, and ICG clearance were measured. At the end of the study, 27 patients had died. Univariate analysis using the Kaplan-Meier method showed that both quantitative liver function tests (galactose elimination capacity:P<0.025; aminopyrine breath test:P<0.001; ICG clearance:P<0.005) and common clinical and biochemical data (encephalopathy:P<0.001; ascites:P<0.001; serum bilirubin:P<0.005; serum albumin:P<0.001; prothrombin index:P<0.05) were significant predictors of survival. To investigate whether quantitative liver function tests could contribute to a better definition of the prognosis, once Pugh score had already been taken into account, a multiple regression analysis according to the Cox model was performed. Pugh score and galactose elimination capacity resulted in the only independent prognostic covariates. From them a prognostic index was calculated, and the model was validated in an additional sample of 70 patients investigated according to the same protocol. The contribution GEC gave to the assessment of overall prognosis over that obtained using the Pugh score was slight, as estimated by the statistical parameters of the Cox's model, but was significant as assessed by a ROC curve analysis (P=0.05). These data show that all quantitative liver function tests were predictors of survival in cirrhosis, and that the galactose elimination capacity added some new prognostic information to those already available using the Child-Turcotte-Pugh classification.This study was supported in part by a grant from the Italian Ministry of Education (National Project Liver Cirrhosis). Part of this study was presented at the 22nd Meeting of the European Society for Clinical Investigation, Graz, Austria, April 20–23, 1988. 相似文献