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91.
CD4+CD25+Foxp3+ regulatory T cells (Treg) specialize in suppressing immune responses. In this study, 47 consecutive colon cancer patients were subjected to circulating Treg frequency assessment by flow cytometry before and after cancer resection. Thirty-two healthy subjects served as controls. Circulating Treg frequencies were significantly higher in colon cancer patients with respect to healthy controls. When patients were subgrouped according to Dukes stages, a linear relationship was observed between Dukes stages and Treg frequencies. In radically resected patients, Treg frequencies were shown to have significantly dropped down. Patients with advanced colon cancer were more likely to have significantly higher proportions of circulating Treg frequencies than Dukes A and B patients when compared to healthy subjects. Of note, nonradically resected patients were found to display reductions in—but not normalization of—Treg frequencies. These results suggest that cancer itself may be able to drive Treg recruitment as a strategy of immunoevasion.  相似文献   
92.
Concurrence of distinct genetic conditions in the same patient is not rare. Several cases involving neurofibromatosis type 1 (NF1) have recently been reported, indicating the need for more extensive molecular analysis when phenotypic features cannot be explained by a single gene mutation. Here, we describe the clinical presentation of a boy with a typical NF1 microdeletion syndrome complicated by cleft palate and other dysmorphic features, hypoplasia of corpus callosum, and partial bicoronal craniosynostosis caused by a novel 2bp deletion in exon 2 of Meis homeobox 2 gene (MEIS2) inherited from the mildly affected father. This is only the second case of an inherited MEIS2 intragenic mutation reported to date. MEIS2 is known to be associated with cleft palate, intellectual disability, heart defects, and dysmorphic features. Our clinical report suggests that this gene may also have a role in cranial morphogenesis in humans, as previously observed in animal models.  相似文献   
93.
Glioblastomas develop de novo (primary glioblastomas) or through progression from low-grade or anaplastic astrocytoma (secondary glioblastomas). There is increasing evidence that these glioblastoma subtypes develop through different genetic pathways. Primary glioblastomas are characterized by EGFR and MDM2 amplification/overexpression, PTEN mutations, and p16 deletions, whereas secondary glioblastomas frequently contain p53 mutations. Loss of heterozygosity (LOH) on chromosome 10 (LOH#10) is the most frequent genetic alteration in glioblastomas; the involvement of tumor suppressor genes, other than PTEN, has been suggested. We carried out deletion mappings on chromosome 10, using PCR-based microsatellite analysis. LOH#10 was detected at similar frequencies in primary (8/17; 47%) and secondary glioblastomas (7/13; 54%). The majority (88%) of primary glioblastomas with LOH#10 showed LOH at all informative markers, suggesting loss of the entire chromosome 10. In contrast, secondary glioblastomas with LOH#10 showed partial or complete loss of chromosome 10q but no loss of 10p. These results are in accordance with the view that LOH on 10q is a major factor in the evolution of glioblastoma multiform as the common phenotypic end point of both genetic pathways, whereas LOH on 10p is largely restricted to the primary (de novo) glioblastoma.  相似文献   
94.
The use of apheretic procedures in pediatric patients has always been restricted by technical difficulties and the low incidence of diseases requiring this kind of treatment. The aim of the present study was to describe the solutions adopted to solve technical difficulties related to priming, vascular access and monitoring and then to evaluate clinical results. Between 1982 and 2000, 51 consecutive children (28 male, 23 female) with a mean age of 4.9 +/- 4.8 years (3 months-14.8 years) and a mean weight of 19.7 +/- 12.8 kg (5-52 kg), with renal and/or extra-renal diseases requiring apheretic procedures were selected for the study. The overall number of procedures performed were: 226 plasma-exchange (PE), 6 LDL-apheresis (LDL-A) and 8 protein A immunoadsorption (IAPA) sessions. Our therapeutic protocol involves hematic flux of 20-100 ml/min and ultrafiltration of 5-20 ml/min. In each 70-95 minute session we exchanged plasmatic volume with fresh frozen plasma or with a solution of 6% albumin in lactated Ringer's, using heparin (10-20 UI/kg/h). We used Paired Filtration Dialysis Monitor in PE and LDL-A; Citem 10 in IAPA. As plasma separator, we used a filter made of polypropylene, 0.2 m2 surface, 30 ml priming (Hemaplex BT 900). Hemolytic uremic syndrome was the most commonly treated disease (18/51 cases) with good results in 10/18 cases. We recorded, good results in vasculitis as well, in one girl with focal glomerulosclerosis in transplanted kidney and rapid improvement in all children with Guillaine-Barré Syndrome. PE treatment was effective in metabolic disorders such as tirosynemia and familiar hypercholesterolemia. Only 4/12 patients with acute liver failure due to viral hepatitis recovered. We had poor results in the remaining eight cases. Complications were rare and no viral infection was found in any patient. Our data show that it is possible to use these procedures in pediatric patients even though clinical indications and real effectiveness still need to be cleared up.  相似文献   
95.
Gastric carcinoma is one of the most frequent malignancies in the world and its clinical behavior especially depends on the metastatic potential of the tumor.In particular,lymphatic metastasis is one of the main predictors of tumor recurrence and survival,and current pathological staging systems reflect the concept that lymphatic spread is the most relevant prognostic factor in patients undergoing curative resection.This is compounded by the observation that two-thirds of gastric cancer in the Western world...  相似文献   
96.
97.
The purpose of this study was to investigate how the ocular surface area (OSA) and the eye blink frequency (BF) are affected by a high versus a low-monitor position during visual display unit (VDU) work with varying cognitive demands. In a balanced randomized (2 × 2) design ten healthy subjects (five males, five females) completed two different tasks on the VDU in a simulated office environment (23°C and 30–35% relative humidity); an active task with demands on vision and hand-eye coordination, and a passive task. Two monitor positions were used: high (the monitors’ upper edge at the same height as the subjects’ eyes) and low (lowered by 25° and perpendicular to gaze angle). Each task lasted 10 min. An OSA-proxy was measured from video recordings, and BF was sampled by electrooculography. The effect of lowering the gaze angle by 25° decreased the OSA-proxy significantly (P < 0.01) during the active task, indicating that a low position of the monitor may be preferable even though the BF also decreased. Overall, the OSA-proxy was 6% higher during the active task compared to the passive while BF during the active task was 69% lower than during the passive task. The low BF during the active task was succeded by a burst with high BF after cessation of the active task, indicating a compensatory blinking process. This stresses that interchange of work tasks with different cognitive load is as important as the monitor position in the prevention of visual and musculoskeletal disorders.  相似文献   
98.
IL-18 is a cytokine structurally and functionally related to IL-1 that, in synergy with IL-12, stimulates the synthesis of IFN-gamma from T lymphocytes and natural killer cells. Because IFN-gamma plays a key pathogenic role in the development of murine immunoinflammatory diabetes induced by multiple low doses of streptozotocin (STZ) we investigated the effect of negating the actions of endogenous IL-18 in this model by administering recombinant IL-18-binding protein:Fc (IL-18 bp:Fc). C57BL/6 mice were injected once daily with 40 mg/kg STZ for 5 consecutive days, day 0 being the first day of STZ challenge. Relative to control animals treated in parallel with either PBS or human IgG, mice treated from day -3 to day 7 with daily doses of 150 microg of IL-18 bp:Fc exhibited lower incidence of diabetes and milder insulitis. In contrast, mice that were treated with IL-18 bp:Fc from day 7 to day 14 exhibited clinical and histological signs of STZ-induced diabetes similar to those of control mice treated with IgG. The protective effect of IL-18 bp:Fc was accompanied by modified ex vivo immune responses, in that spleen cells and peritoneal macrophages contained fewer IFN-gamma secreting cells and released lower amounts of nitrite (an index of nitric oxide production) and IL-1beta. We conclude that intact IL-18 function is essential for the full diabetogenic effect of low dose STZ in C57BL/6 mice.  相似文献   
99.
The efficacy of alpha interferon (IFN-α) in the treatment of severe type II essential mixed cryoglobulinemia (EMC) has been reported previously. In some patients, the development of neutralizing antibodies to recombinant IFN-α (rIFN-α) can affect the clinical response achieved with rIFN-α; a second treatment with natural IFN-α preparations may reinduce the clinical response. In the present study the ability of leukocyte IFN (LeIFN) to restore the response was investigated from a pharmacodynamic viewpoint. Specifically, the pharmacodynamic profiles of different IFN-α preparations were studied by measuring the serum neopterin levels and the levels of expression of protein MxA mRNA in in vivo peripheral blood mononuclear cells in two patients with EMC whose resistance to rIFN-α2a treatment increased concomitantly with the development of neutralizing antibodies. These markers were measured before injection and at 24 and 48 h after a single injection of rIFN-α2a, consensus IFN [(C)IFN], or LeIFN. No increase or only a slight increase in MxA mRNA levels was detectable after administration of rIFN-α2a or (C)IFN, whereas a significant increase (≥10-fold) in MxA mRNA expression was recorded following administration of LeIFN. The neutralizing antibodies to rIFN-α2a cross-react with (C)IFN. Sera from these patients neutralized most but not all of the subtypes present in the natural IFN-α (LeIFN) mixture, and no significant increase in neopterin levels was observed after these patients were switched to LeIFN treatment. In summary, the data demonstrate that the problem of neutralizing antibodies still exists and that LeIFN may induce an increase in the level of MxA mRNA expression but not an increase in neopterin levels in patients who are resistant to treatment with rIFN-α2a or (C)IFN.  相似文献   
100.
The p16(INK4a) is a cyclin-dependent kinase inhibitor that decelerates the cell cycle by inactivating the cyclin-dependent kinases involved in the phosphorylation of the retinoblastoma protein (RB). Expression of E6 and E7 oncogenes of high-risk (HR) human papillomavirus (HPV), affecting the RB-p16 pathway, leads to p16 upregulation. Although it is widely reported that p16 is overexpressed in a high percentage of preneoplastic lesions and in almost all carcinomas of the uterine cervix, protein upregulation and its correlation with HPV infection in low-grade lesions is still being debated. In this study, we investigated in parallel, p16 expression and HPV infection in 100 cervical biopsies (17 normal tissues, 54 CIN1, 10 CIN2, 11 CIN3, eight invasive squamous cancers). Results obtained demonstrated that none of the 17 normal cervical tissues, evaluated by immunohistochemistry, presented p16 positivity whereas, starting from CIN1 (31%) to CIN2 (90%), CIN3 (100%) and carcinomas (100%), a constant and significant increase of protein overexpression (P<0.0001) was observed. In addition, p16 overexpression consistently showed elevated sensitivity (84%) and specificity (98%) in detecting HR-HPV infection with a high positive predictive value (97%) and negative predictive value (86%). Of interest, 93% of the p16-positive CIN1 were also HR-HPV infected. Our findings confirmed that p16 overexpression is associated to high-grade precancerous lesions and cervical carcinomas, and further demonstrated that immunohistochemical evaluation of p16 may be a useful biomarker in identifying HR-HPV-infected low-grade lesions.  相似文献   
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