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11.
Human T lymphocyte subsets, identified by means of OKT3, 4 and 8 monoclonal antibodies, were isolated by a fluorescence activated cell sorter (FACS IV) and analyzed for distribution of alpha-naphthyl acetate esterase (ANAE) activity. As compared to OKT8+ lymphocytes a higher proportion of OKT4+ lymphocytes was ANAE-positive exibiting a spot or dot-like pattern in the cytoplasm. OKT8 and 4 positive subsets showed a similar ANAE distribution in diffuse granular form. Although OKT4 and OKT8 populations presented a different ANAE dot-like reactivity, this marker did not allow as clear a distinction between them as that reported for TG and TM lymphocytes.  相似文献   
12.
Oleoylethanolamide (OEA) is a naturally occurring bioactive lipid belonging to the family of N-acylethanolamides. A variety of beneficial effects have been attributed to OEA, although the greater interest is due to its potential role in the treatment of obesity, fatty liver, and eating-related disorders. To better clarify the mechanism of the antiadipogenic effect of OEA in the liver, using a lipidomic study performed by 1H-NMR, LC-MS/MS and thin-layer chromatography analyses we evaluated the whole lipid composition of rat liver, following a two-week daily treatment of OEA (10 mg kg−1 i.p.). We found that OEA induced a significant reduction in hepatic triacylglycerol (TAG) content and significant changes in sphingolipid composition and ceramidase activity. We associated the antiadipogenic effect of OEA to decreased activity and expression of key enzymes involved in fatty acid and TAG syntheses, such as acetyl-CoA carboxylase, fatty acid synthase, diacylglycerol acyltransferase, and stearoyl-CoA desaturase 1. Moreover, we found that both SREBP-1 and PPARγ protein expression were significantly reduced in the liver of OEA-treated rats. Our findings add significant and important insights into the molecular mechanism of OEA on hepatic adipogenesis, and suggest a possible link between the OEA-induced changes in sphingolipid metabolism and suppression of hepatic TAG level.  相似文献   
13.
Twenty-six patients with locally advanced, inoperable gastric cancer were treated with carboplatin, epidoxorubicin, 5-fluorouracil (FEP) plus alpha 2b interferon. Total gastrectomy was performed in patients achieving clinical complete or partial response. The overall response rate after neoadjuvant chemotherapy was 67%. In 13/15 patients undergoing surgery no residual tumor was evident after resection. After a median follow-up of 14 months, 4/13 disease-free patients have relapsed. The median survival time is 13 months for all patients, and 19 months for disease-free patients; in four patients survival time exceeds twenty-four months. Our multimodality program is effective in locally advanced gastric cancer and warrants further evaluation.  相似文献   
14.
Twenty-two patients with locally advanced inoperable gastric cancer received neoadjuvant chemotherapy with a modified 5-fluorouracil, doxorubicin, methotrexate (FAMTX) regimen. The patients who achieved at least a stable disease were considered eligible for surgery with curative intent, which was performed in 19 cases. 16 patients (all responsive to neoadjuvant chemotherapy) were rendered disease-free by the combined approach. No treatment-related deaths occurred; grade III leukopenia was observed in only 3 cases. The preliminary results of this study indicate the feasibility of our treatment approach; randomized trials are awaited to properly evaluate the role of neoadjuvant chemotherapy in locally advanced gastric cancer.  相似文献   
15.
The lack of decisive progress in ovarian cancer chemotherapy in recent years led the ARTAC "Ovary" group to initiate a study based on the hypothesis of collateral sensitivities. In this phase I-II trial, NHO-88, the V-H combination (associating vinorelbine (VNB) and hexamethylmelamine (HMM) was studied in patients with advanced ovarian adenocarcinomas, most of which had become resistant to previous chemotherapy. The aim of the study was to find an active combination without complete cross resistance with first-line platinum salt based combinations, such as CAP, FAP or CACb-300. A pilot feasibility study was first carried out to determine the maximum tolerated weekly dose (MTWD) of VNB (20 mg/m2/week), HMM being administered per os on days 1-14 of every 28-day cycle at a standard dose of 250 mg/m2/day. An open phase II-A study was further carried out according to a 2-step sequential analysis method for phase II clinical trials. We observed: 1), a good tolerance of the V-H combination apart from frequent neutropenia; 2), a response rate of 35% (95% confidence interval: 23-47%); 3), a median response duration of 4 months (range: 1-7 months); 4), in some cases, the absence of a complete cross-resistance between the V-H regimen and the previously administered platinum-based combinations. These results, which are currently being validated (phase II-B ongoing), constitute the first step in the search for active systems of sequential or alternate chemotherapeutic regimens for the treatment of advanced carcinomas.  相似文献   
16.
BACKGROUND: It is not known whether total circulating lipid hydroperoxides are increased in insulin-resistant individuals and whether this correlates with depletion of liposoluble antioxidant vitamins that are consumed during lipid peroxidation. OBJECTIVE: The goal of this study was to define the relation between resistance to insulin-mediated glucose disposal and plasma concentrations of lipid hydroperoxides and liposoluble antioxidant vitamins in healthy volunteers. DESIGN: Insulin-mediated glucose disposal was determined in 36 healthy, nondiabetic volunteers by measuring their steady-state plasma insulin (SSPI) and glucose (SSPG) concentrations in response to a 180-min constant infusion of octreotide, insulin, and glucose. In addition, fasting plasma concentrations of lipid hydroperoxides and liposoluble antioxidant vitamins were determined by using the FOX 2 assay and liquid chromatography. RESULTS: Statistically significant direct relations were observed between SSPG and mean arterial blood pressure (r = 0.44, P: = 0.008) and plasma lipid hydroperoxide concentrations (r = 0.42, P: = 0.01), whereas significant inverse correlations were found between SSPG and alpha-carotene (r = -0.58, P: = 0.0002), beta-carotene (r = -0.49, P: = 0.004), lutein (r = -0.35, P: = 0.04), alpha-tocopherol (r = -0. 36, P: = 0.04), and delta-tocopherol (r = -0.45, P: = 0.007). CONCLUSIONS: Variations in insulin-mediated glucose disposal in healthy individuals are significantly related to plasma concentrations of lipid hydroperoxides and liposoluble antioxidant vitamins. These findings suggest that total plasma lipid peroxidation is increased in insulin-resistant individuals at an early, preclinical stage, ie, well before the development of glucose intolerance and type 2 diabetes.  相似文献   
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18.
Treatment of neurodegenerative diseases represents a major challenge for the pharmaceutical industry. Key to developing novel and efficacious therapeutics is the discovery of new druggable targets. Toward this aim, the current drug discovery process is strongly relying on the improved understanding of disease mechanisms and on a synergistic approach with chemistry, molecular biology and robotics. In this scenario, we present the case of a newly discovered molecular mechanism that may be of interest for drug discovery programmes in Huntington's disease and other neurodegenerative diseases.  相似文献   
19.
The ankylosed spine is prone to fracture even after minor trauma due to its changed biomechanical properties. The two central features of ankylosing spondylitis (AS) that promote the pathological remodeling of the spine are inflammation and new bone formation. AS is also associated with osteoporosis that is attributed to an uncoupling of the bone formation and bone resorption processes. Therefore, bone resorption occurs and promotes weakening of the spine as well as increased risk of vertebral fractures which can be hugely different in terms of clinical relevance. Even in the presence of symptomatic clinical vertebral fractures, the diagnosis can be overruled by attributing the pain to disease activity. Furthermore, given the highly abnormal structure of the spine, vertebral fracture diagnosis can be difficult on the basis of radiography alone. CT can show the fractures in detail. Magnetic resonance imaging is considered the method of choice for the imaging of spinal cord injuries, and a reasonable option for exclusion of occult fractures undetected by CT. Since it is equally important for radiologists and clinicians to have a common knowledge base rather than a compartmentalized view, the aim of this review article was to provide the required clinical knowledge that radiologists need to know and the relevant radiological semiotics that clinicians require in diagnosing clinically significant injury to the ankylosed spine.  相似文献   
20.
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