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31.
β-N-Acetylhexosaminadases in human cerebrospinal fluid and serum of patients with multiple sclerosis
Alessandro Datti Carla Emiliani Giuseppe Capocchi Aldo Orlacchio 《Clinica chimica acta; international journal of clinical chemistry》1991,200(2-3)
β-N-Acetylhexosaminidase activity and isoenzyme have been investigated in normal human cerebrospinal fluid and that of patients with multiple sclerosis. β-N-acetylhexosaminidase activity in normal cerebrospinal fluids has been resolved into five components. The major component was in a form that eluted from DEAE cellulose at the same salt concentration as hexosaminidase As, the isoenzyme previously identified in human serum. Cerebrospinal fluid from patients exhibited a different isoenzyme profile, showing a remarkable increase in a form having a pI which was more acidic than that of As. These changes have a potential use in the diagnosis and further biochemical characterization of multiple sclerosis. 相似文献
32.
Salvatore Metafora Gianfranco Peluso Gianpietro Ravagnan Magda Marchese Michele di Pietro Aldo Mancini Nicola Panza Antonio Fusco Raffaele Porta 《Medical oncology (Northwood, London, England)》1988,5(4):223-231
Transglutaminase (TGase) activity was reduced in intact mitogen-stimulated human peripheral blood lymphocytes (PBL) when compared to intact resting PBL. Moreover, a treatment of the same quiescent immunocompetent cells with purified liver TGase and Ca2+ completely suppressed the mitogen-induced blast transformation. A decrease in TGase activity in neoplastically transformed seminal vesicle epithelial cells with respect to their normal parent counterpart was also observed. Our data support the notion of a possible implication of TGase in cell proliferation and transformation. 相似文献
33.
Dina Ruano António Macedo Ana Dourado Maria Jo?o Soares José Valente Isabel Coelho Vítor Santos Maria Helena Azevedo Ann Goodman Mara Helena Hutz Clarissa Gama Maria Inês Lobato Paulo Belmonte-de-Abreu Joana Almeida Palha 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2004,(1):41-45
34.
Pelosi G Scarpa A Veronesi G Spaggiari L Del Curto B Moore PS Maisonneuve P Sonzogni A Masullo M Viale G 《Virchows Archiv : an international journal of pathology》2005,447(6):969-977
Nuclear translocation of β-catenin has been correlated with epidermal growth factor receptor (EGFR) overexpression/activation
in nonsmall cell lung cancer. Less is known on β-catenin transactivation in high-grade pulmonary neuroendocrine tumors and
on the status of β-catenin activating EGFR and human epidermal growth factor receptor 2 (HER-2) or β-catenin target genes
cyclin D1 and matrix metalloproteinase-7 (MMP-7). β-catenin immunoreactivity was evaluated in 51 large-cell neuroendocrine
carcinomas (LCNEC) and 45 small-cell lung carcinomas (SCLC). Nineteen cases were assessed for β-catenin gene exon 3 mutations, expression of MMP-7, and expression/gene amplification of EGFR, HER-2, and cyclin D1. β-catenin was
expressed in all 96 high-grade neuroendocrine tumors, the vast majority (94%) showing >50% immunopositive cells. A disarrayed
immunoreactivity, however, was commonly encountered consisting in variably altered membrane-associated patterns of staining
along with progressive accumulation of cytoplasmic immunoreactivity. In LCNEC, but not in SCLC, the disarrayed patterns correlated
with EGFR and HER-2 protein expression. β-catenin nuclear accumulation was found in nine tumors, including seven LCNEC and
two SCLC, and was always associated with disarrayed immunoreactivity and increased MMP-7, but not cyclin D1 expression. These
cases, however, did not show β-catenin gene mutations or EGFR and HER-2 gene amplification or expression. No association was found between nuclear β-catenin and
any clinicopathological variable including patients' survival. The subcellular compartmentalization of β-catenin is profoundly
altered in high-grade pulmonary neuroendocrine tumors. A minor subset of these tumors shows β-catenin nuclear accumulation
in association with increased expression of MMP-7, but not of cyclin D1, independent of EGFR and HER-2 gene amplification
or expression.
The authors have no significant financial or other relationship with the manufacturers of any commercial products or commercial
services presented in this paper 相似文献
35.
Portugal K Dozmorov I Sidorov I Marrero I Fonseca JA Spadafora-Ferreira M Kalil J Coelho V 《International immunology》2001,13(6):747-755
We addressed the question of whether allo-transplantation (Tx) induces breakdown of tolerance to self-antigens or alteration of the autoreactive T cell repertoire in humans. The serial variation of T cell autoreactivity was studied in the peripheral blood of 12 renal transplant patients, by autologous limiting dilution assay and autologous mixed lymphocyte reaction. Ten of 12 patients presented a positive response in autologous peripheral blood mononuclear cells in the post-Tx period, in contrast to four of 12 patients before Tx (P = 0.038). Multi-hit kinetics was found in 57% of the assays analyzed, indicating frequent regulatory control of the autologous response. Quantitative analysis performed in eight patients showed an increase in precursor frequency at >1 year post-Tx in five patients. These data indicate that autoreactivity increases or develops following Tx, in humans. Post-Tx events such as alloreactivity, infections or immunosuppression could interfere with the balance of autoreactive and regulatory cells, leading to changes in the T cell repertoires to self-antigens and eventually breakdown of self-tolerance. Further investigation is needed to elucidate whether post-Tx autoreactivity contributes to rejection, plays a regulatory role over alloreactivity or both, at separate times. 相似文献
36.
Genotypes and haplotypes in the IL-1 gene cluster: analysis of two genetically and diagnostically distinct groups of Alzheimer patients 总被引:5,自引:0,他引:5
Seripa D Matera MG Dal Forno G Gravina C Masullo C Daniele A Binetti G Bonvicini C Squitti R Palermo MT Davis DG Antuono P Wekstein DR Dobrina A Gennarelli M Fazio VM 《Neurobiology of aging》2005,26(4):455-464
Increased risk of Alzheimer's disease (AD) has been associated with polymorphisms in the IL-1 gene cluster, and in particular with the IL-1alpha-889 T/T genotype. However, this association is still unclear, and needs further investigation. In order to clarify the role of these polymorphisms in the complex pathogenesis of AD we examined genotype and haplotype frequencies of the two C-to-T SNPs at position -889 and -551 in the IL-1alpha and IL-1beta genes, respectively, and of the 86 bp VNTR intron-2 polymorphisms in the IL-1Ra gene. The analysis was performed in two genetically and diagnostically distinct groups of sporadic AD from Italy and the USA. In the Italian group a significant association between the IL-1alpha-889 T/T genotype and AD (OR=3.022, 95% CI: 1.001-9.119) was found, whereas no difference was found in the group from the USA. Results were also compared with previously published studies that analyzed the same IL-1 polymorphisms in AD. In both groups, the analysis of the estimated haplotypes shows that AD patients and controls who carry the IL-1beta-511 C allele, were also more frequently carriers of the IL-1Ra 1 allele (haplotypes -C-1). The total frequency of the two -C-1 haplotypes (C-C-1 plus T-C-1) was about one half of the total frequency of the eight estimated haplotypes. This was confirmed by significant linkage disequilibrium between these two loci in both the Italian and USA groups. In the Italian group a weak association of the T-C-2 haplotype with the disease (OR=1.648, 95% CI: 1.519-1.788) was also found, whereas in the USA group no difference was found. Although ours and other published data on different samples of Caucasian and non-Caucasian AD show a great heterogeneity in the frequencies of the IL-1alpha-889, the IL-1beta-511 and the IL-1Ra VNTR gene polymorphisms, we confirm the role of the IL-1alpha-889 T/T genotype as a risk factor for sporadic AD, and show the presence of an allelic association between IL-1beta C and IL-1Ra 1 alleles in both the Italian and the USA groups, confirmed by the presence of significant levels of linkage disequilibrium between these two loci. 相似文献
37.
N19 polyepitope as a carrier for enhanced immunogenicity and protective efficacy of meningococcal conjugate vaccines 总被引:2,自引:0,他引:2
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Baraldo K Mori E Bartoloni A Petracca R Giannozzi A Norelli F Rappuoli R Grandi G Del Giudice G 《Infection and immunity》2004,72(8):4884-4887
N19, a string of human universal CD4 T-cell epitopes from various pathogen-derived antigens, was shown to exert a stronger carrier effect than CRM197 for the induction of anti-group C Neisseria meningitidis capsular polysaccharide (MenC), after immunization of mice with various dosages of N19-MenC or CRM-MenC conjugate vaccines. After two immunizations, the N19-based construct induced anti-MenC antibody and protective bactericidal antibody titers higher than those induced by three doses of the CRM-MenC conjugate and required lower amounts of conjugate. N19-based conjugates are superior to CRM-based conjugates to induce protective immune responses to MenC conjugates. 相似文献
38.
Pincivero DM Coelho AJ Campy RM Salfetnikov Y Bright A 《European journal of applied physiology》2002,87(4-5):448-455
The purpose of this study was to examine the effect of voluntary contraction efforts on the median frequency (f
med) of the electromyogram (EMG) recorded from the quadriceps femoris muscle in healthy men and women. A group of 30 healthy
volunteers (15 men, 15 women) were assessed for EMG activity of the vastus medialis (VM), vastus lateralis (VL), and rectus
femoris (RF) muscles during isometric contractions with the knee at 60° flexion. Subjects performed a series of 5 s maximal
voluntary isometric contractions that anchored the perceptual range with a "10" on a 10-point scale. Sub-maximal isometric
contractions were then separately performed at the following perceived effort levels on the 10-point scale: 1, 2, 3, 4, 5,
6, 7, 8 and 9, in a random order. Subjects were instructed to maintain the contraction at each perceived level of effort for
5 s. The f
med of the three muscles was assessed using a power spectrum analysis performed over 11 consecutive, 512 ms, epochs overlapping
each other by half their length during the middle 3 s of each contraction. The f
med for each of the 11 epochs was then determined for each muscle, followed by calculation of the means and normalized coefficients
of variation [(standard deviation/mean)×100%] for each contraction. The results demonstrated that the mean f
med of VL was significantly greater than those of the other two muscles, and that f
med of RF was significantly greater than that of VM. The VL muscle demonstrated a significant increase in mean f
med across the contraction efforts, compared to the VM and RF muscles that displayed a significant decrease. The men displayed
significantly higher f
med values for the VM muscle than did the women, as well as showing a significantly greater increase across the contraction efforts
for the VL muscle. The variability of f
med was shown to be significantly higher for the VM muscle, compared to the VL and RF muscles. The findings of this study suggest
that the f
med statistic is most sensitive to contraction intensity efforts for the VL muscle, and that men display significantly higher
values for the VL and VM muscles, compared to women.
Electronic Publication 相似文献
39.
F G Araujo P M Coelho L H Pereira J Pellegrino 《Clinical and experimental immunology》1977,28(2):289-291
Skin-graft rejection in mice experimentally infected with Schistosoma mansoni is delayed when grafting is performed 60 days after the infection. In mice infected 30 days prior to the grafting, the grafts were rejected at the same time both in infected and in control animals. This observation indicates that impairment of cell-mediated immune response occurs in mice with mature S. mansoni infections. 相似文献
40.