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61.
Studies in both animal models and humans have shown a subset of B cells behaving as immuno-regulatory cells, being a source of inhibitory cytokines such as IL-10 and TGF-β. Our aims were to establish the presence of human B regulatory (Breg) cells and to assess their ability to suppress proliferation of CD4(+) T cells and to mediate T regulatory (Treg) cells' properties. For this purpose, human Breg, CD4(+) T and Treg cells were purified using magnetic microbeads. CFSE-labeled CD4(+) T cells were stimulated and cultured alone or with Breg cells. Their proliferative response was determined 72 hours later based on the CFSE staining. In parallel, Treg cells were cultured alone or with Breg cells in different conditions for 24 hours, and then stained and analyzed for Foxp3 and CTLA-4 expression. We found that, the co-culture of Breg cells (defined as CD25(high) CD27(high) CD86(high) CD1d(high) IL-10(high) TGF-β(high)) with autologous stimulated CD4(+) T cells decreased significantly (in a dose-dependent way) the proliferative capacity of CD4(+) T cells. Furthermore, Foxp3 and CTLA-4 expression in Treg cells were enhanced by non-stimulated and further by ODN-CD40L stimulated Breg cells. The regulatory function of Breg cells on Treg cells was mainly dependent on a direct contact between Breg and Treg cells, but was also TGF-β but not IL-10 dependent. In conclusion, human Breg cells decrease the proliferation of CD4(+) T cells and also enhance the expression of Foxp3 and CTLA-4 in Treg cells by cell-to-cell contact. 相似文献
62.
Yakirevich E Matoso A Sabo E Wang LJ Tavares R Meitner P Morris DJ Pareek G Delellis RA Resnick MB 《Human pathology》2011,42(11):1684-1692
63.
64.
H4 acetylation, XIST RNA and replication timing are coincident and define x;autosome boundaries in two abnormal X chromosomes 总被引:2,自引:1,他引:2
The inactive X (Xi) differs from its active homologue (Xa) in a number of
ways, including increased methylation of CpG islands, replication late in S
phase, underacetylation of histone H4 and association with XIST RNA. Global
changes in DNA methylation occur relatively late in development, but the
other properties all change during or shortly after the establishment of Xi
and may play a role in the mechanism by which an inactive chromatin
conformation spreads across most of the chromosome. In the present report,
we use two human X;autosome translocation chromosomes to study the
spreading of inactive X chromatin across X;autosome boundaries. In one of
these chromosomes, t(X;6), Xp distal to p11.2 is replaced by 6p21.1-6pter
and, in the other, ins(X;16), a small fragment derived from 16p13 is
inserted into the distal third of Xq. In lymphoid cells from patients
carrying these translocations in an unbalanced form, Xi was shown by HUMARA
assay to be derived exclusively [t(X:6)] or predominantly [ins (X;16)] from
the derived X chromosome. We used a combination of immunolabelling and
RNA/DNA fluorescence in situ hybridization to define the distribution of
XIST RNA, deacetylated H4 and late-replicating DNA across the two derived X
chromosomes in inactive form. Within the limits of the cytogenetic
techniques employed, the results show complete coincidence of these three
parameters, with all three being excluded from the autosomal component of
the derived X chromosome.
相似文献
65.
Yehudit Peerless Einav Simon Edmond Sabo Ofer Ben-Izhak Dov Hershkovitz 《Experimental and molecular pathology》2013
Introduction
Heparanase, the sole heparan sulfate degrading enzyme, has a role in cellular invasion. Accordingly, a large number of studies have demonstrated an association between heparanase expression and tumor stage and patients' prognosis. In colon carcinoma, heparanase shows increased expression in tumor compared to normal tissue and its expression correlates with the presence of metastasis. One of the regulatory mechanisms of heparanase expression is de-methylation on its promoter. In the present study we evaluated the role of heparanase promoter methylation in colon carcinoma.Material and methods
Analysis of heparanase promoter methylation was done on 32 samples of colon carcinoma as well as 30 samples of normal colonic mucosa. DNA was extracted from FFPE tissue and subjected to bisulfite conversion. The relative fraction of methylated and unmethylated DNA was evaluated using quantitative real-time PCR.Results
The fraction of methylated DNA was 1 ± 3.4% in the colon carcinoma group, and 2.5 ± 3.3% in the normal colon group (P = 0.11). Only one case in the normal group and one case in the tumor group showed more than 10% methylation in the heparanase promoter.Conclusion
We did not find any significant difference in heparanase promoter methylation between colon carcinoma and normal colonic mucosa, suggesting that heparanase overexpression in colon carcinoma is mediated by other mechanisms. 相似文献66.
BM Winklhofer-Roob MA van't Hof DH Shmerling 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(10):1132-1136
The aim of this study was to determine the efficacy of long-term oral β -carotene supplementation for correcting impaired β -carotene status in cystic fibrosis patients. Thirty-five patients (2.3-30.5 years of age) with coefficients of fat absorption of 46-96% (median 88%) received β -carotene 0.5 mg/kg daily and were followed over a 16-month treatment period. Baseline plasma β -carotene concentrations in patients (meanSD, 0.090.06 μ mol/1) were significantly lower than those of age-matched controls (0.860.56 μ mol/1) ( p < 0.0001). Concentrations increased rapidly and reached a plateau at or before 3 weeks that was maintained throughout the study period. Values obtained at 3 weeks (0.890.64 μ mol/1) were significantly higher ( p < 0.0001) than those at baseline and did not differ from controls. Plasma retinol and α -tocopherol concentrations increased during the observation period, but remained within normal ranges. Plasma retinyl palmitate, which was below the detection limit in all but one patient at baseline, did not increase. Thus oral β -carotene supplementation is effective and normalizes β -carotene status of cystic fibrosis patients without evidence of significant side effects. β -Carotene, cystic fibrosis, LDL-cholesterol, oral supplementation, retinol, α-tocopherol 相似文献
67.
MA Hurrell C McLean P Desmond BM Tress A Kaye 《Journal of Medical Imaging and Radiation Oncology》1995,39(1):86-89
A case of malignant granular cell tumour of the sciatic nerve is presented. Computed tomography demonstrated iso-density with muscle and minimal enhancement. Magnetic resonance demonstrated T1 isointensity with muscle with marked enhancement, and isointensity with fat on proton and T2 images. Pathological evidence is presented for its probable Schwann cell histogenesis. 相似文献
68.
E. Zuckerman E. Toubi T. D. Golan T. Rosenvald-Zuckerman E. Sabo Z. Shmuel D. Yeshurun 《British journal of cancer》1995,72(2):447-451
This study was undertaken to determine the prevalence of anti-cardiolipin antibodies (ACLAs) in patients with malignancy and to investigate a possible association of ACLAs with thromboembolic events in such patients. The study included 216 patients with solid and non-solid malignancies and an age-matched control group of 88 healthy subjects. ACLA levels were measured and related to thromboembolic phenomena (diagnosed by imaging methods) that occurred within 12 months of the diagnosis of cancer. Forty-seven patients (approximately 22%) with cancer were ACLA positive as compared with only three subjects (approximately 3%) in the control group (P < 0.0001). The ACLA-positive cancer patients had a significantly higher rate of thromboembolic events than ACLA-negative cancer patients: 13 of 47 (28%) vs 24 of 169 (14%), respectively (P < 0.05). High titres of either IgG-ACLA or IgM-ACLA were found in 10 out of 13 ACLA-positive cancer patients with thrombotic complications, but in only 2 out of 34 cancer ACLA-positive patients without thromboembolic events (P < 0.0001). In four cancer patients in whom ACLA levels were followed ACLA decreased after successful surgery/chemotherapy treatment and remained negative and thromboembolic free for 12 months of follow-up. Patients with malignancies show an increased prevalence of ACLA. Furthermore, ACLA-positive patients, mainly those with high titres, are much more prone to thromboembolic events. 相似文献
69.
BRITT-LOUISE SUNESON RN CHRISTER LINDHOLM MD DMSc ELISABETH HAMRIN RN BM DMSc 《European journal of cancer care》1996,5(1):7-12
The clinical incidence of lymphoedema of the arm in breast cancer patients was studied before and after general mammography screening in the country of jönköping, Sweden. There was a significant decrease of incidence of lymphoedema from 15% in 1983 to 8% in 1988. Clinical and pathological therapy data have been analysed in relation to lymphoedema. Significant factors contributing to lymphoedema were the number of lymph nodes examined and the number of pathologically positive lymph nodes. A higher proportion of patients receiving post-operative radiotherapy to the axilla developed lymphoedema, compared with those with surgery alone.
A comparison between the two groups is impossible due to the fact that post-operative radiotherapy was prescribed only to patients with pathologically positive lymph nodes. 相似文献
A comparison between the two groups is impossible due to the fact that post-operative radiotherapy was prescribed only to patients with pathologically positive lymph nodes. 相似文献
70.
Bauduceau O De Revel T Fogelman J Amadou S Souleau B Nedellec G 《Annales de médecine interne》2003,154(3):183-186
Spontaneous hematoma in the ilio-psoas muscle is an uncommon condition, usually observed as a complication of anticoagulation or hemophilia. Clinically, the onset is marked by violent pain in the territory of femoral nerve and/or psoitis. The diagnosis is confirmed by echography or CT-scan. The most serious complications are loss of self-sufficiency and neuro-muscular after-effect. Surgery is recommended in patients with neurological suffering, followed by early physiotherapy. We report the case of a 42-year-old man, with an ilio-psoas muscle hematoma, revealing chronic myeloid leukemia, without any hemostasis disorder. 相似文献