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Sex- and age-related nephrotoxicity due to 1,2-dichloropropane was studied in vitro by means of renal cortical slices obtained from Wistar rats. Reduced glutathione content, organic anion accumulation (p-aminohippurate), and release of malondialdehyde (to measure the extent of lipid peroxidation), aspartate aminotransferase, -glutamyltransferase and lactate dehydrogenase into the incubation medium were determined. Sex differences in naive rats parameters were slight, but male were more susceptible to toxic effects of 1,2-dichloropropane than female rats; glutathione depletion, lipid peroxidation, and loss of organic anion accumulation were higher in male than in female slices. During senescence, naive male rats showed a progressive decrease of glutathione content (statistically significant from 7–9 months of age), increase of spontaneous lipid peroxidation from the same age, and increase of signs of cytotoxicity (release of aspartate aminotransferase and lactate dehydrogenase into the incubation medium) from 3–4 months of age. A loss of organic anion accumulation started from 7–9 months of age. Slices from rats of 3–4 months old showed the apparently highest susceptibility to 1,2-dichloropropane but depletion of glutathione content and loss of organic anion accumulation were at the same level in the oldest rats. The age decrease of control values caused the differences in the percentage ratio and then, apparently, a lower DCP effect. On the contrary, the increase of aspartate aminotransferase released in the incubation medium by DCP-treated slices corresponded to the age-related increase in cytotoxicity.The work was presented in part to the 1st National Conference of the Molecular and Cellular Toxicology Group, Siena 30. 11.–1.12.1990.  相似文献   
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PURPOSE: The epidermal growth factor receptor (EGFR) may play a relevant role in the progression, hormone therapy resistance, and prognosis of prostate cancer patients. Also MDM2, a negative p53 regulator that interacts with retinoblastoma (Rb), E2F, p19(arf) and the ras-mitogen-activated protein kinase(MAPK) cascade plays an important role in prostate cancer progression and prognosis. On the basis of the EGFR and MDM2 role in integrating signaling pathways critical for prostate cancer progression, we investigated whether their selective combined blockade may have a cooperative antitumor effect in prostate cancer. For this purpose, we have used the EGFR tyrosine kinase inhibitor gefitinib (ZD1839, Iressa) and a second generation hybrid oligonucleotide antisense MDM2 (AS-MDM2), respectively. EXPERIMENTAL DESIGN: Gefitinib and AS-MDM2 were administered to hormone-refractory and hormone-dependent human prostate cancer cells in vitro and to mice bearing tumor xenografts, evaluating the effects on growth, apoptosis, and protein expression, in vitro and in vivo. RESULTS: We demonstrated that the combination of gefitinib and AS-MDM2 synergistically inhibits the growth of hormone-independent prostate cancer cells in vitro. This effect is accompanied by the inhibition of MDM2, phosphorylated Akt (pAkt), phosphorylated MAPK (pMAPK), and vascular endothelial growth factor (VEGF) expression and by Rb hypophosphorylation. The combination of the two agents in nude mice bearing the same hormone-independent tumors caused a potent cooperative antitumor effect. Tumor samples analysis confirmed the inhibition of MDM2, pAkt, pMAPK, VEGF, and basic fibroblast growth factor expression. CONCLUSIONS: This study shows that EGFR and MDM2 play a critical role in the growth of prostate cancer, especially hormone-dependent, and that their combined blockade by gefitinib and AS-MDM2 causes a cooperative antitumor effect, supporting the clinical development of this therapeutic strategy.  相似文献   
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PURPOSE: Helicobacter pylori causes gastric damage and is involved in gastric carcinogenesis. Vascular endothelial growth factor (VEGF) plays a major role in gastric mucosa repair and is overexpressed in gastric cancer. We investigated: (a) whether H. pylori, and in particular H. pylori VacA toxin, affected VEGF expression in gastric epithelial cells in culture; and (b) the signal transduction pathway involved in any effect exerted by H. pylori. EXPERIMENTAL DESIGN: MKN-28 cells were incubated with uninoculated BCF (control) or with BCF obtained from VacA-producing wild-type H. pylori 60190 strain or from its isogenic mutant 60190:v1, specifically lacking vacA gene in the presence or absence of ZD 1839, a selective inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase, PD098059, a selective inhibitor of mitogen-activated protein (MAP)/extracellular signal-regulated kinase (ERK) kinase, the kinase responsible for ERK phosphorylation, or SC-236, a selective inhibitor of cyclooxygenase (COX)-2 for 24-48 h. RESULTS: (a) Toxigenic H. pylori up-regulated VEGF mRNA and protein expression and caused a 2.5-fold increase in VEGF release compared with control, whereas nontoxigenic H. pylori did not; (b) H. pylori VacA toxin-induced up-regulation of VEGF was counteracted by selective inhibition of EGFR tyrosine kinase; (c) toxigenic H. pylori activated the ERK/MAP kinase cascade, and inhibition of MAP kinase activation counteracted H. pylori-induced VEGF up-regulation; (d) toxigenic H. pylori up-regulated COX-2 expression, and this effect was counteracted by blockade of EGFR tyrosine kinase; and (e) COX-2 selective inhibition counteracted H. pylori-induced up-regulation of VEGF. CONCLUSION: (a) H. pylori up-regulates VEGF expression in gastric epithelial cells; and (b) this effect is specifically related to VacA toxin and seems to depend on the activation of an EGFR-, MAP kinase-, and COX-2-mediated pathway.  相似文献   
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In the last decades, international guidelines proposed different strategies of complementary foods introduction during weaning to prevent allergy. Avoidance measures, such as late introduction of allergenic foods, failed to show a significant preventive effect towards allergy. Recently, prospective randomized controlled studies suggested that the early introduction of solid foods ‐ rather than the late introduction ‐ could be a strategy to prevent allergic sensitization and food allergy. However, at today clear evidence of effectiveness and safety of early introduction are not yet available to recommend a radical change in the current clinical practice. A realistic advice for the general population could be to begin the weaning at 4–5 months with the progressive introduction of different foods. The advices for introduction of solid foods during weaning should also take in consideration the global development of child to chose the better timing of introduction of foods.  相似文献   
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While many with schizophrenia spectrum disorders experience difficulties understanding the feelings of others, little is known about the psychological antecedents of these deficits. To explore these issues we examined whether deficits in mental state decoding, mental state reasoning and metacognitive capacity predict performance on an emotion recognition task. Participants were 115 adults with a schizophrenia spectrum disorder and 58 adults with substance use disorders but no history of a diagnosis of psychosis who completed the Eyes and Hinting Test. Metacognitive capacity was assessed using the Metacognitive Assessment Scale Abbreviated and emotion recognition was assessed using the Bell Lysaker Emotion Recognition Test. Results revealed that the schizophrenia patients performed more poorly than controls on tests of emotion recognition, mental state decoding, mental state reasoning and metacognition. Lesser capacities for mental state decoding, mental state reasoning and metacognition were all uniquely related emotion recognition within the schizophrenia group even after controlling for neurocognition and symptoms in a stepwise multiple regression. Results suggest that deficits in emotion recognition in schizophrenia may partly result from a combination of impairments in the ability to judge the cognitive and affective states of others and difficulties forming complex representations of self and others.  相似文献   
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Here we describe Hb F-Avellino [Gγ41(C7)Phe?→?Leu; HBG2: c.124?T?>?C], a new hemoglobin (Hb) variant observed in a healthy newborn. The proband’s hemolysate was found to be mildly unstable by the isopropanol test. The occurrence of the variant was assessed by both chromatographic and electrophoretic methods. DNA sequencing analysis of the Gγ gene showed a T to C transition at codon 41 (TTC?>?CTC) corresponding to the Phe?→?Leu substitution. Normal functional properties have been hypothesized.  相似文献   
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Young adults with personality disorders (PD) other than borderline are in urgent need of validated treatments to help them in managing important life transitions. Therapeutic interventions focused upon social and interpersonal difficulties may facilitate these individuals in maximizing opportunities for employment, forming stable romantic relationships, and belong to social groups. It is also important that they are offered evidence-based, first-line time-limited treatments in order to maximize effectiveness and reduce costs. We developed a 16-session programme of group-based Metacognitive Interpersonal Therapy (MIT-G) including psychoeducation on the main interpersonal motives, an experiential component enabling practice of awareness of mental states; and use of mentalistic knowledge for purposeful problem-solving. We report a feasibility, acceptability, and clinical significance randomized clinical trial. Participants meeting inclusion criteria were randomized to receive MIT-G (n = 10) or waiting list+TAU (n = 10). Dropout rate was low and session attendance high (92.19%). Participants in the MIT-G arm had symptomatic and functional improvements consistent with large effect sizes. In the MIT-G arm similarly large effects were noted for increased capacity to understand mental states and regulate social interactions using mentalistic knowledge. Results were sustained at follow-up. Our findings suggest potential for applying MIT-G in larger samples to further test its effectiveness in reducing PD-related symptoms and problematic social functioning.  相似文献   
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