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1.
Intraperitoneal (i.p.) administration of a cadmium (Cd) salt at concentrations of 1.0, 2.5 and 4.0 mg CdCl2/kg body wt. caused severe liver injury in rats 24 h after administration. The toxic effects were most evident in the intermediate dose of 2.5 mg. Thymidine kinase (TK), the key enzyme of the salvage pathway of DNA biosynthesis, was affected in all Cd-treated groups. TK activity presented lower values at the highest Cd-induced hepatotoxicity.  相似文献   
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AIMS: Over-expression of cellular metallothionein occurs frequently in human tumours but the underlying mechanism remains unknown. The aim of this study was to assess metallothionein expression in cases of lung carcinoma and to correlate it with histopathological parameters. METHODS AND RESULTS: Tumour tissue samples from 89 patients with lung carcinoma were immunostained by the streptavidin-biotin-peroxidase technique, using a monoclonal antibody against both metallothionein-1 and -2 isoforms. Positive matallothionein immunostaining was prominent in 44 out of 89 (49%) and negative in 45 out of 89 (51%) cases of lung carcinoma examined. Metallothionein positivity was prominent in 32 out of 43 (74%) cases of squamous cell lung carcinoma, and in 12 out of 35 (34%) cases of adenocarcinoma, while it was negative in all 11 cases of small-cell lung carcinoma examined, presenting a statistically significant difference between the different histological types. The intensity of metallothionein staining revealed a statistically significant difference between the squamous cell and adenocarcinoma cases examined. The pattern and extent of metallothionein staining in tumour cells and the expression of metallothionein in stromal cells were not correlated with histopathological parameters (type and grade) in metallothionein-positive cases of lung carcinoma examined. No association was found between metallothionein expression and lymph node status in the examined cases of lung carcinoma. CONCLUSIONS: Our findings indicate that expression of metallothionein was evident in squamous cell lung carcinoma and adenocarcinoma, but absent in small-cell lung carcinoma, supporting evidence for participation of this protein in the biological mechanisms underlying the carcinogenic evolution in the lung.  相似文献   
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Type I interferons (IFNs) are pleiotropic cytokines that exert multiple effects on normal and tumor cells. These effects are supposedly mediated through the stimulation of several signal transduction pathways by type I IFNs. These include the well-studied canonical Jak-Stat pathway, largely responsible for the antiviral and growth-inhibitory activities of IFNs, as well as the phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways, whose importance in IFN-induced biologic outcomes has not been precisely established. One of the effects of type I IFNs on tumor cells is the induction of programmed cell death, apoptosis, which has been studied extensively over the last decade and has been suggested to be an important effector mechanism for IFN's antitumor effects in the treatment of cancer. The aim of this review is to summarize and discuss the recent data in the field of type I IFN-induced apoptosis, with special emphasis on the molecular mechanisms of apoptosis and on the role of alternative noncanonical signaling pathways stimulated by type I IFNs in this process.  相似文献   
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Abstract

For seven weeks, 37 overweight adults followed a hypocaloric diet based on Orthodox Fasting (OF). A hypocaloric, time restricted eating (TRE) plan (eating between 08:00 to 16:00?h, water fasting from 16:00 to 08:00?h) was followed by 23 Body Mass Index (BMI)-matched participants. Anthropometric, glycaemic and inflammation markers and serum lipids were assessed before and after the diets. Both OF and TRE groups demonstrated reductions in BMI (28.54?±?5.45 vs 27.20?±?5.10?kg/m2, p?<?0.001 and 26.40?±?4.11 vs 25.81?±?3.78?kg/m2 p?=?0.001, respectively). Following the intervention, the OF group presented lower concentrations of total and low-density lipoprotein-cholesterol, compared with the pre-fasting values (178.40?±?34.14 vs 197.17?±?34.30?mg/dl, p?<?0.001 and 105.89?±?28.08 vs 122.37?±?29.70?mg/dl, p?<?0.001, respectively). Neither group manifested significant differences in glycaemic and inflammatory parameters. Our findings suggest that OF has superior lipid lowering effects than the TRE pattern.  相似文献   
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AIM: Acute gastrointestinal bleeding is a severe complication in patients receiving long-term oral anticoagulant therapy. The purpose of this study was to describe the causes and clinical outcome of these patients. METHODS: From January 1999 to October 2003, 111 patients with acute upper gastrointestinal bleeding (AUGIB) were hospitalized while on oral anticoagulants. The causes and clinical outcome of these patients were compared with those of 604 patients hospitalized during 2000-2001 with AUGIB who were not taking warfarin. RESULTS: The most common cause of bleeding was peptic ulcer in 51 patients (45%) receiving anticoagulants compared to 359/604 (59.4%) patients not receiving warfarin (P<0.05). No identifiable source of bleeding could be found in 33 patients (29.7%) compared to 31/604 (5.1%) patients not receiving anticoagulants (P=0.0001). The majority of patients with concurrent use of non-steroidal anti-inflammatory drugs (NSAIDs) (26/35, 74.3%) had a peptic ulcer as a cause of bleeding while 32/76 (40.8%) patients not taking a great dose of NSAIDs had a negative upper and lower gastrointestinal endoscopy. Endoscopic hemostasis was applied and no complication was reported. Six patients (5.4%) were operated due to continuing or recurrent hemorrhage, compared to 23/604 (3.8%) patients not receiving anticoagulants. Four patients died, the overall mortality was 3.6% in patients with AUGIB due to anticoagulants, which was not different from that in patients not receiving anticoagulant therapy. CONCLUSION: Patients with AUGIB while on long-term anticoagulant therapy had a clinical outcome, which is not different from that of patients not taking anticoagulants. Early endoscopy is important for the management of these patients and endoscopic hemostasis can be safely applied.  相似文献   
8.
BACKGROUND: During the past years, major advances in the management of upper gastrointestinal diseases have been achieved. The aim of this study was to determine if changes in indications for upper gastrointestinal endoscopy and endoscopic findings have occurred during the last 15 years in our area. METHODS: Indications for upper gastrointestinal tract endoscopy and endoscopy findings of patients who underwent upper endoscopy in years 1990, 1995, 2000, and 2005 in our department were compared. RESULTS: Over the 15-year period, the number of diagnostic endoscopies performed in our department in years 1990, 1995, 2000, and 2005 increased (953, 1245, 2350, and 2528, respectively). Acute upper gastrointestinal bleeding had become less frequent (40%, 42.8%, 19.7%, 14.3%, P<0.001), but dyspepsia (24.4%, 33.6%, 54.3%, 51.3%, P=0.002) and reflux (1.8%, 1.3%, 5.1%, 10.8%, P=0.005) more frequent indications for upper endoscopy. The endoscopic findings of duodenal ulcer (39.1%, 22.5%, 20.5%, 9.3%, P<0.001), gastric ulcer (15.9%, 8.3%, 5.7%, 4.6%, P=0.036) as well as erosive gastroduodenitis (35.6%, 22.2%, 15.3%, 4.7%, P<0.001) decreased, whereas that of reflux esophagitis (3.1%, 10.1%, 12%, 16%, P=0.034) increased. Moreover, the percentage of patients with negative endoscopy or minimal endoscopic findings (eg, nonerosive gastritis) increased (12.8%, 33.7%, 54.1%, 64.4%, P<0.001). CONCLUSIONS: In south-western Greece, dyspepsia and reflux as an indication for upper endoscopy have been increasing, whereas acute upper gastrointestinal bleeding has been decreasing. The finding of peptic ulcers at the upper gastrointestinal tract endoscopy has become significantly less frequent, while the percentage of patients with negative results of endoscopy seems to have been increasing rapidly.  相似文献   
9.
OBJECTIVES: Hepatic steatosis is a common feature of chronic hepatitis C. The purpose of this study was to determine factors related to the presence of steatosis and to define the role of steatosis in the response to antiviral treatment in chronic hepatitis C patients. METHODS: We retrospectively analysed all patients with chronic hepatitis C treated in a 5 year period in our department. Patients were included in the study only if a pretreatment liver biopsy specimen was available for evaluation. All patients treated either with interferon in combination with ribavirin, or with pegylated interferon in combination with ribavirin were included irrespectively of their response (early, end of treatment and/or sustained) to antiviral therapy. RESULTS: A total of 116 patients with chronic hepatitis C were included in the study with a mean age of 45.5 +/- 14.1 years. Steatosis was present in 52 patients (44.8%). On univariate analysis age, P = 0.04 and body mass index > or = 25, P = 0.004 were correlated with the presence of steatosis and on multivariate analysis only body mass index > or = 25, P = 0.032. Advanced fibrosis was not found associated with steatosis. Sixty patients out of 116 (51.7%) had sustained virological response (SVR). In particular 42 out of 64 patients with no steatosis (65.6%) had SVR compared to 20 out of 52 patients (38.4%) with any degree of steatosis (P = 0.009). Patients with genotype 2 or 3 had a more favourable outcome compared to patients with 1 or 4 genotypes, 63.2% vs 49.2%, P = 0.032. Also increased age (P = 0.0001), gamma glutamyltransferase (GGT) (P = 0.029), no history of intravenous drugs use (P = 0.001) and advanced fibrosis on pretreatment biopsy (P = 0.046) were correlated with treatment failure. On multivariate analysis significant independent association with SVR was found with the presence of steatosis on pretreatment biopsy (P = 0.004), increased GGT (P = 0.005) and genotype (P = 0.017). CONCLUSION: Steatosis in the liver biopsy performed before the beginning of antiviral treatment was found to be associated only to the body mass index of the patients and to be a strong independent factor for treatment failure.  相似文献   
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