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In our previous studies, voacamine, a bisindolic alkaloid extracted from Peschiera fuchsiaefolia, was examined for its possible capability of enhancing the cytotoxic effect of doxorubicin (DOX) on multidrug resistant (MDR) human osteosarcoma cells (U-2 OS-R). Voacamine induced in resistant cells a significant increase of drug retention and intranuclear location which became comparable to those observed in the parental sensitive counterparts (U-2 OS-WT). In the present study, the cell survival analysis and the electron microscopic observations confirmed the evident cytotoxicity of DOX on MDR cells after pre-treatment with the plant extract. Moreover, an increase of the reactivity of P-glycoprotein (P-gp) with the monoclonal antibody UIC2, which recognizes an epitope of the drug transporter in its functional conformation, was revealed, demonstrating that voacamine is a substrate of P-gp, thus acting as a competitive antagonist of the cytotoxic agent. Moreover, to investigate if the enhancement of the cytotoxic effect induced by voacamine could be due to an apoptotic process, we carried out the analysis of cell morphology after Hoechst staining and the quantification of apoptosis by Annexin V-FITC assay. These evaluations showed a very low rate of apoptosis in U-2 OS-R cells treated with voacamine and DOX given in association. In addition, the combined treatment induced ultrastructural modifications suggestive of autophagic cell death. In particular, transmission electron microscopy observations revealed the presence of numerous lysosomes and the formation of a large number of autophagosomes containing residual digested material. In conclusion, these findings seem to indicate that voacamine is capable of enhancing the cytotoxic effect of DOX on MDR cells by favouring a lethal autophagic process.  相似文献   
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Background  

Pulmonary dysfunction following cardiac surgery is believed to be caused, at least in part, by a lung vascular injury and/or atelectasis following cardiopulmonary bypass (CPB) perfusion and collapse of non-ventilated lungs.  相似文献   
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Background  

Shoulder disorders are a common health problem in western societies. Several treatment protocols have been developed for the clinical management of persons with shoulder pain. However available evidence does not support any protocol as being superior over others. Systematic reviews provide some evidence that certain physical therapy interventions (i.e. supervised exercises and mobilisation) are effective in particular shoulder disorders (i.e. rotator cuff disorders, mixed shoulder disorders and adhesive capsulitis), but there is an ongoing need for high quality trials of physical therapy interventions. Usually, physical therapy consists of active exercises intended to strengthen the shoulder muscles as stabilizers of the glenohumeral joint or perform mobilisations to improve restricted mobility of the glenohumeral or adjacent joints (shoulder girdle). It is generally accepted that a-traumatic shoulder problems are the result of impingement of the subacromial structures, such as the bursa or rotator cuff tendons. Myofascial trigger points (MTrPs) in shoulder muscles may also lead to a complex of symptoms that are often seen in patients diagnosed with subacromial impingement or rotator cuff tendinopathy. Little is known about the treatment of MTrPs in patients with shoulder disorders.  相似文献   
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Alzheimer's disease (AD) is a neurodegenerative disorder with mixed cognitive and behavioural clinical manifestations. The possession of apolipoprotein-E (ApoE) epsilon4 allelic variant is one of the most important risk factors for developing late-onset AD (LOAD). In this study we analysed the relationship between the entire range of behavioural symptoms, cognitive deficit, and sociodemographic characteristics and ApoE epsilon4 allele possession with multivariate logistic regression models in LOAD patients. Patients included (n = 171) were consecutively admitted in a memory clinic for the first diagnostic visit. Levels of behaviour and cognition within the last month were assessed by the Neuropsychiatric Inventory and Mini Mental State Examination. Presence of clinically significant psychosis, delusions and hallucinations at the early stage of the illness, from the onset to the first visit, was measured with diagnostic criteria. ApoE epsilon4 allele possession was associated with increased levels of delusions within the last month from the first visit (OR 1.23; 95% CI 1.01-1.50; P < 0.05) and with the presence of categorical delusions at the early stage until the first visit (OR 3.11; 95% CI 1.21-8.01; P < 0.02). In this study, which considers the entire range of behavioural expressions in LOAD patients at the early stage of the illness, the relationship between behaviour and ApoE epsilon4 allele is confirmed for delusions only.  相似文献   
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BACKGROUND: Nitric oxide (NO) plays a key role in wound repair and S-nitrosothiols like S-nitrosoglutathione (GSNO) are well known NO donors. METHODS: Animals were separated in two groups and submitted to excisional wounds on the dorsal surface at the first day. GSNO (100 microm)-containing hydrogels were topically applied on the wound bed in the GSNO group, daily, during the first 4 days. Control group was topically treated with hydrogel without GSNO for the same period. Wound contraction and re-epithelialization were measured. Animals were sacrificed 21 days after wounding. Samples of lesion and normal tissue were formalin-fixed, paraffin embedded for histological analysis. RESULTS: Wound contraction, measured 14 and 21 days after wounding, was greater in the GSNO group than in the control group (P<0.05 for both). The re-epithelialized wound area, measured 14 days after wounding, was higher in the GSNO group than in the control group (P<0.05). A higher amount of inflammatory cells was observed in superficial and deep areas of the granulation tissue of the control group compared to the GSNO group. Twenty-one days after wounding, thin red-yellow collagen fibers arranged perpendicularly to the surface were found in the granulation tissue of the control group, whereas in the GSNO-treated group collagen fibers were thicker and arranged parallel to the surface. Increased number of mast cells was observed in the GSNO group compared with that in the control group. Vascularization and myofibroblast distribution were similar in both groups. CONCLUSION: Topical application of GSNO-containing hydrogel during the early phases of rat cutaneous wound repair accelerates wound closure and re-epithelialization and affects granulation tissue organization.  相似文献   
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Because various immune functions are impaired at temperatures only 1 degrees to 3 degrees C less than normal, we tested the hypothesis that mild hypothermia during anesthesia impairs resistance to dermal infections. Guinea pigs were anesthetized for 6 hours with 1% inspired halothane. Their core temperatures were maintained at either 39 degrees C (normal for guinea pigs, n = 12) or 36 degrees C (n = 12). Two hours after induction of anesthesia, three doses each of Staphylococcus aureus (10(8), 10(7), and 10(6) organisms) were injected intradermally at nine sites on each animal's back. Core temperatures were not controlled after recovery from the anesthetic, and animals in each group were maintained in the same environment. Four days after anesthesia, each injection site was excised to obtain a count of viable bacteria. Subcutaneous oxygen partial pressure values, averaged over time, were 53 +/- 3 mm Hg (mean +/- SEM) in the hypothermic group and 62 +/- 4 mm Hg in the normothermic group (p = 0.06). Capillary perfusion, as assessed by laser Doppler flowmetry, was comparable in the two groups. One day after injection of 10(8) bacteria, the area of induration was 89 +/- 11 mm(2) in the hypothermic group but only 61 +/- 6 mm(2) in the normothermic group (p < 0.05). On postanesthetic day 4, the area of induration was 72 +/- 6 and 59 +/- 6 mm(2) in the hypothermic and normothermic groups, respectively (p > 0.05). After inoculation with 10(8) bacteria, the fraction recovered was 1.0 +/- 0.2 in the hypothermic groups and 0.6 +/- 0.2 in the normothermic group (p < 0.05). After inoculation with 10(7) and 10(6) bacteria, the fraction recovered was less than 0.2, and no difference was found between the hypothermic and normothermic animals. Thus mild hypothermia during halothane-induced anesthesia slightly impairs resistance to dermal infection.  相似文献   
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Abdominal trauma: use of oral contrast material for CT is safe   总被引:2,自引:0,他引:2  
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