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Considering the well-documented protection of acetylcysteine (AC) in hepatotoxicity related to acetaminophen, we studied the preventive potential of AC against mild hepatotoxicity of CCl4, potentiated with ethyl alcohol (ETH) and the role of tissue glutathione. Rats fed a liquid diet with 30% of energy from ETH, had-intraperitoneal CCl4 administered in three injections, at 7-day intervals. AC was ingested at the level for acetaminophen overdose. ETH markedly potentiated the injury induced by CCl4, as evidenced by higher values of serum alanine aminotransferase (ALT), urinary bile acids (BA), serum creatinine, histological score of liver cell necrosis, mortality and by lower body weights and lower liver glutathione, when compared with CCl4 alone. Protective effect of AC consisted of a lesser hepatocytic necrosis, better body weights and higher liver glutathione. We conclude, that AC favorably modifies liver damage induced by CCl4 and potentiated with ETH. There is a preventive role for AC in subjects who combine ETH overuse with exposure to hepatotoxic xenobiotics, whose toxicity is modified by tissue glutathione.  相似文献   
3.
The infectivity of blood and lymphoid organs of mice persistently infected with lymphocytic choriomeningitis virus was found to be predominantly associated with lymphocytes and both T and B cells were infectious. A hypothesis is presented in which it is assumed that lymphocytes in carrier mice are infected via their LCM virus-specific antigen receptors, thereby leading to their antigen-triggered clonal expansion followed by infection and functional inactivation.  相似文献   
4.
Annals of Surgical Oncology - The liver-first approach in patients with synchronous colorectal liver metastases (CRLM) has gained wide consensus but its role is still to be clarified. We aimed to...  相似文献   
5.
BCL-2 protein is a oncoprotein considered to have an important role in the regulation of programmed cell death--apoptosis. The intracellular localization, the relation with other oncoproteins, the antioxidant function and the pathological implications are discussed.  相似文献   
6.
Hematopoietic xenografts were carried out in three experiments using goat fetal liver (44-48 days, experiments I and II) or purified human CD 34+ cells (experiment III) as the donor cells. Recipients were sheep fetuses at 41-47 days of gestation. Goat fetal liver cells were either injected without any pretreatment or stimulated by preincubation in a culturing in goat phytohemagglutinin-stimulated lymphocyte supernatant. Human CD 34+ myeloid progenitor cells were purified from bone marrow by minimacs immunomagnetic purification and cultured in medium supplemented with stem cell factor, IL3, and IL6. Goat-sheep chimerism was assessed by flow cytometry analysis (FCA) of peripheral blood and bone marrow cells using a mouse anti-goat CD 45 monoclonal antibody and by karyotype analysis of peripheral blood from goat/sheep chimeras. Human cell engraftment was assessed by polymerase chain reaction amplification of the human DAX1 gene in blood and bone marrow DNA from sheep which had received human cells. In the three experiments, a mean of 76% (26 of 34) of injected fetuses were born alive without any clinical evidence of graft-versus-host disease. Three lambs were found to be goat/sheep chimeric after flow cytometry analysis (peripheral blood and bone marrow) and karyotype (peripheral blood) analysis. Both tissues continued to express goat cells at 6 or 12 months (last assessment) depending on the experiment. No human chimerism was detected using polymerase chain reaction amplification in peripheral blood and bone marrow of any of the six sheep grafted with human cells. These data and those also obtained on other species (human, pig/sheep) show that it is possible to carry out hematopoietic xenografts using the sheep fetus as recipient provided both donor and recipient fetal cells are processed during the period of tolerance to foreign antigens.  相似文献   
7.
In order to detect the subcellular localization of calcium in the myocardium of laboratory animals (rats and guinea-pigs) under the influence of 2'-(2-diethylaminoethoxy)-3-phenyl-propiophenone (etafenone, Baxacor) (4 mg, 20 mg and 100 mg/kg body weight) two ultracytochemical methods, with lead acetate and with potassium pyroantimonate, were used. In addition, X-ray microanalysis of myocardial fragments was performed. The correlation of ultrastructural, ultracytochemical and X-ray microanalytical findings provides direct evidence of the hypothesis that etafenone acts on myocardium as a so-called "calcium antagonist". The subcellular targets of etafenone action are mainly the sarcoplasmic reticulum and mitochondria. Etafenone modifies also the concentration of copper, zinc and selenium in myocardium. The effect of etaferone on myocardial calcium and oligoelements appears to be dose-dependent.  相似文献   
8.
PURPOSE: The idiotype (Id) of the immunoglobulin on a given B-cell malignancy is a clonal marker that can serve as a tumor-specific antigen. We developed a novel vaccine formulation by incorporating Id protein with liposomal lymphokine that was more potent than a prototype, carrier-conjugated Id protein vaccine in preclinical studies. In the present study, we evaluated the safety and immunogenicity of this vaccine in follicular lymphoma patients. EXPERIMENTAL DESIGN: Ten patients with advanced-stage follicular lymphoma were treated with five doses of this second generation vaccine after chemotherapy-induced clinical remission. All patients were evaluated for cellular and humoral immune responses. RESULTS: Autologous tumor and Id-specific type I cytokine responses were induced by vaccination in 10 and 9 patients, respectively. Antitumor immune responses were mediated by both CD4+ and CD8+ T cells, were human lymphocyte antigen class I and II associated, and persisted 18 months beyond the completion of vaccination. Specific anti-Id antibody responses were detected in four patients. After a median follow-up of 50 months, 6 of the 10 patients remain in continuous first complete remission. CONCLUSIONS: This first clinical report of a liposomal cancer vaccine demonstrates that liposomal delivery is safe, induces sustained tumor-specific CD4+ and CD8+ T-cell responses in lymphoma patients, and may serve as a model for vaccine development against other human cancers and infectious pathogens.  相似文献   
9.
BACKGROUND: To determine the efficacy, impact on quality-of-life (QoL) and tolerability of two different irinotecan administration schedules in combination with capecitabine as first-line treatment of metastatic colorectal cancer. PATIENTS AND METHODS: We carried out a randomized phase II trial to select one of the following treatment regimens for further investigation: weekly irinotecan at a dose of 70 mg/m(2) days 1, 8, 15, 22, 29 (arm A) or 3-weekly irinotecan at a dose of 300/240 mg/m(2) day 1 and days 22 (arm B) in combination with capecitabine 1000 mg/m(2) twice daily days 1-14 and days 22-35 every 6 weeks. RESULTS: Seventy-five patients with good performance status entered the trial. The two arms were well balanced for relevant patient and disease characteristics. The most frequent toxic effects were grade 3/4 diarrhea (arm A: 34%, B: 19%), grade 3/4 neutropenia (A: 5%, B: 19%) and grade 2/3 alopecia (A: 26%, B: 65%). Other grade 3/4 toxic effects were rare (<5%). Response rates were 34% [95% confidence interval (CI) 20% to 51%] in arm A and 35% (95% CI: 20% to 53%) in arm B. Median time to progression was 6.9 (4.6-10.1) and 9.2 (7.9-11.5) months and median overall survival was 17.4 (12.6-23.0+) and 24.7 (16.3-26.4+) months. Patients with an objective tumor response reported better physical well-being (P < 0.01), mood (P < 0.05), functional performance (P < 0.05) and less effort to cope (P < 0.05) compared with the non-responders and stable disease patients. CONCLUSIONS: The primary end point of this study was the objective response rate and based on the statistical design of the trial, the 3-weekly irinotecan schedule was selected over weekly irinotecan administration. The 3-weekly irinotecan schedule also seemed advantageous in terms of grade 3/4 diarrhea, time to progression, overall survival and patient convenience, but the study was not designed to detect differences in these parameters. In addition, tumor response was shown to have a beneficial effect on QoL indicators.  相似文献   
10.
Introduction: We followed patients with pulmonary arterial hypertension (PAH) receiving specific vasodilator therapy and tested for predictors of clinical outcome. Methods: Thirty‐two patients (mean age 39 ± 15 years, 22 women, diagnosed with pulmonary hypertension; PH): 29 with PAH and 3 patients with inoperable chronic thromboembolic PH received therapy with either bosentan, sildenafil, or both and were evaluated with clinical parameters, biomarkers (B‐type natriuretic peptide values), and echocardiography before receiving specific medication and every 3 months thereafter. A right heart catheterization was performed at baseline. A composite endpoint of death, worsening of functional class, or the need of a second vasodilator agent was used to define the clinical nonresponders. Results: Patients were followed for 14 months (7.5–21). The endpoint was reached by 15 patients: four patients died (two idiopathic PAH and two PAH in context of Eisenmenger syndrome), seven patients showed 1 functional class worsening, and four patients needed to be switched to combination therapy. Patients who remained clinically stable or improved had at baseline a better cardiac output with a less remodeled right ventricle (RV) and better functioning RV (all P < 0.05). A RV fractional area change (RVFAC) lower than 25.7% and a RV global strain value higher than ?13.4% predict with 87% sensitivity and 83% specificity (AUC 87.3%, P = 0.001) and 73% sensitivity and 91% specificity (AUC 84.2%, P = 0.003), respectively, patients who will deteriorate clinically under specific vasodilator therapy. A multivariate model showed RVFAC to be the only independent predictor of the endpoint with a HR of 0.87 (0.8–0.96), P = 0.007. Conclusions: Over an average period of 1 year, almost half of patients showed signs of clinical deterioration despite specific vasodilator therapy. Parameters of right ventricular morphology and function had prognostic value in these patients.  相似文献   
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