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61.
62.
Cova L Ratti A Volta M Fogh I Cardin V Corbo M Silani V 《Stem cells and development》2004,13(1):121-131
In the past few years research on stem cells has exploded as a tool to develop potential therapies to treat incurable neurodegenerative diseases. Stem cell transplantation has been effective in several animal models, but the underlying restorative mechanisms are still unknown. Several events such as cell fusion, neurotrophic factor release, endogenous stem cell proliferation, and transdifferentiation (adult cell acquisition of new unexpected identities) may explain therapeutic success, in addition to replacement of lost cells. This issue needs to be clarified further to maximize the potential for effective therapies. Preliminary stem transplantation trials have already been performed for some neurodegenerative diseases. There is no effective pharmacological treatment for amyotrophic lateral sclerosis, but recent preliminary data both in experimental and clinical settings have targeted it as an ideal candidate disease for the development of stem cell therapy in humans. This review summarizes recent advances gained in stem cell research applied to neurodegenerative diseases with a special emphasis to the criticisms put forward. 相似文献
63.
Macchi C Popolizio A Casamorata F Bicchi S Pieroni A Molino Lova R Miniati B Gulisano M Catini C Conti AA Gensini GF 《Italian journal of anatomy and embryology = Archivio italiano di anatomia ed embriologia》2002,107(2):93-97
Fifty-four subjects, aged between 20 and 35 years, divided into two subgroups, respectively 30 healthy subjects (17 males and 13 females) and 24 subjects with "gonalgia sine materia" (13 males and 11 females) underwent isokinetic exercise test in order to compare their dominant limb with the not dominant one as regard as the strength of extensor and flexor muscles of the knee. No statistically significant difference was found in any of the studied parameters in the comparison between the dominant limb and the not dominant one, both within the subgroup of healthy subjects and within the subgroup of subjects with "gonalgia sine materia". Authors conclude that psychological features may play a preeminent role in the genesis, as well as in the maintenance of "gonalgia sine materia", thus confirming previous data available in medical literature. 相似文献
64.
Cell proliferation in breast cancer is a major determinant of clinical outcome in node-positive but not in node-negative patients. 总被引:2,自引:0,他引:2
Davide Treré Claudio Ceccarelli Mario Migaldi Donatella Santini Mario Taffurelli Elena Tosti Pasquale Chieco Massimo Derenzini 《Applied immunohistochemistry & molecular morphology》2006,14(3):314-323
The growth rate of a tumor cell population depends on two major factors: the percentage of proliferating cells (cell growth fraction) and the rapidity of their duplication (cell proliferation rate). The authors evaluated the prognostic and predictive value of both kinetics parameters in a large series of breast cancer patients (n=504). The cell growth fraction was determined by MIB-1 immunostaining, the cell proliferation rate by AgNOR analysis. Ki-67 LI (labeling index) and AgNOR area were significantly associated with histotype, histologic grade, tumor size, estrogen/progesterone receptor status, patient age, and lymph node involvement (P<0.005). In the entire series of patients, both kinetics variables were significantly and independently associated with the clinical outcome, but their prognostic relevance was quite different when node-negative and node-positive patients were considered separately. Although in node-positive patients Ki-67 LI and AgNOR area were the unique independent predictors of disease-free and overall survival, they were excluded by the multivariate Cox model in node-negative patients, where only tumor size and estrogen receptor status retained a significant P-value. These results show that in breast carcinoma the cell growth fraction and the cell proliferation rate have a different prognostic impact with respect to the lymph node status and are major determinants of clinical outcome in node-positive patients only. Within this subgroup, the rapidity of cell proliferation as assessed by AgNOR analysis also served as a sensitive predictor of the response to adjuvant treatments. 相似文献
65.
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
66.
A MicroRNA signature associated with prognosis and progression in chronic lymphocytic leukemia 总被引:2,自引:0,他引:2
67.
68.
Ignazio Di Fazio Massimo Motta Salvatore Musumeci Sergio Neri Giovanni Pistone Mariano Malaguarnera 《Journal of interferon & cytokine research》2004,24(10):594-599
Determination of serum iron levels in patients affected by chronic hepatitis C is considered fundamental for studying the response to interferon-alpha (IFN-alpha) treatment. IFN could induce anemia, which is promptly corrected by exogenous administration of recombinant human erythropoietin (rHuEPO). The aim of our study was to verify the possible beneficial effect of rHuEPO in patients affected by chronic hepatitis C and treated with IFN. Seventy consecutive patients (42 males and 28 females, mean age 46.4+/-5.2 years) affected by chronic hepatitis C were enrolled. In all patients, chronic hepatitis C was diagnosed on the basis of clinical and biological findings (alanine aminotransferase [ALT] serum levels at least 2-fold higher than normal values for at least 12 months and the presence of anti-HCV antibodies). All patients were negative for hepatitis B virus (HBV) infection, hepatitis D virus (HDV infection, and HIV infection. Statistical analysis was carried out using the Wilcoxon nonparametric sum rank test, the Spearman correlation rank test, and the Friedman ANOVA and Kendall coefficient of concordance. At the end of the treatment, our study series showed significant differences in serum levels of AST (p < 0.001), iron (p < 0.001), and ferritin (p < 0.001). At the end of the follow-up period, significant differences were seen in ALT, aspartate (AST), and iron ferritin and transferrin levels. All differences favored patients who received IFN-alpha and rHuEPO. We think that the depletion of circulating iron may improve the immune response impaired by iron accumulation in the liver. Our study confirms the important role played by iron in the response to IFN treatment, suggesting that the use of rHuEPO induces a better response to IFN in patients with chronic hepatitis C by activation of erythropoiesis. 相似文献
69.
Metes D Logar A Rudert WA Zeevi A Woodward J Demetris AJ Abu-Elmagd K Eghtesad B Shapiro R Fung JJ Trucco M Starzl TE Murase N 《Human immunology》2003,64(8):787-795
Passenger leukocytes have been demonstrated to play significant roles in initiating and also regulating immune reactions after organ transplantation. Reliable techniques to detect donor leukocytes in recipients after organ transplantation are essential to analyze the role, function, and behavior of these leukocytes. In this report we describe a simple, reliable method to detect donor cells with low frequencies using peripheral blood samples. Detection of small numbers of major histocompatibility complex (MHC) mismatched cells was first studied using four-color flow cytometry in artificially created cell mixtures. By selecting the CD45(+) population and simultaneous staining with several leukocyte lineage markers (CD3, CD4, CD8, CD56, and CD19), MHC-mismatched leukocytes were consistently detected in cell suspensions prepared from directly stained whole blood samples with a threshold sensitivity as low as 0.1%-0.2%. When the fresh peripheral blood mononuclear cells were separated by conventional Ficoll gradient purification, similar, but slightly lower levels of donor cells were detected. Blood samples obtained 1-5 months after liver, kidney, and intestine transplants revealed that the kind of organ allograft influenced levels and lineage pattern of the circulating donor cells. This procedure provided a simple and reliable method in determining early chimerism in transplant recipients. However, the detection of MHC-mismatched leukocytes of all lineages was much lower when frozen peripheral blood mononuclear cells were used. 相似文献
70.
De Luca A Buccino A Gianni D Mangino M Giustini S Richetta A Divona L Calvieri S Mingarelli R Dallapiccola B 《Human mutation》2003,21(2):171-172
The high mutation rate at the NF1 locus results in a wide range of molecular abnormalities. The majority of these mutations are private and rare, generating elevated allelic diversity with a restricted number of recurrent mutations. In this study, we have assessed the efficacy of denaturing high-performance liquid chromatography (DHPLC), for detecting mutation in the NF1 gene. DHPLC is a fast and highly sensitive technique based on the detection of heteroduplexes in PCR products by ion pair reverse-phase HPLC under partially denaturing conditions. We established theoretical conditions for DHPLC analysis of all coding exons and splice junctions of the NF1 gene using the WAVEmaker software version 4.1.40 and screened for mutations a panel of 40 unrelated NF1 patients (25 sporadic and 15 familial), genetically uncharacterized. Disruptive mutations were identified in 29 individuals with an overall mutation detection rate of 72.5%. The mutations included eight deletions (exons 4b, 7, 10a, 14, 26, and 31), one insertion (exon 8), nine nonsense mutation (exons 10a, 13, 23.1, 27a, 29, 31, and 36), six missense mutations (exons 15, 16, 17, 24, and 31), four splice errors (exons 11, 14, 36, and 40) and a complex rearrangement within exon 16. Eighteen (62%) of the identified disruptive mutations are novel. Seven unclassified and three previously reported polymorphisms were also detected. None of the missense mutations identified in this study were found after screening of 150 controls. Our results suggest that DHPLC provides an accurate method for the rapid identification of NF1 mutations. 相似文献