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41.
PURPOSE: In early clinical trials with patients receiving highly emetogenic chemotherapy, the neurokinin antagonist aprepitant significantly enhanced the efficacy of a standard antiemetic regimen consisting of a type-three 5-hydroxytryptamine antagonist and a corticosteroid. This multicenter, randomized, double-blind, placebo-controlled phase III study was performed to establish definitively the superiority of the aprepitant regimen versus standard therapy in the prevention of chemotherapy-induced nausea and vomiting (CINV). PATIENTS AND METHODS: Patients receiving cisplatin > or = 70 mg/m2 for the first time were given either standard therapy (ondansetron and dexamethasone on day 1; dexamethasone on days 2 to 4) or an aprepitant regimen (aprepitant plus ondansetron and dexamethasone on day 1; aprepitant and dexamethasone on days 2 to 3; dexamethasone on day 4). Patients recorded nausea and vomiting episodes in a diary. The primary end point was complete response (no emesis and no rescue therapy) on days 1 to 5 postcisplatin, analyzed by a modified intent-to-treat approach. Treatment comparisons were made using logistic regression models. Tolerability was assessed by reported adverse events and physical and laboratory assessments. RESULTS: The percentage of patients with complete response on days 1 to 5 was significantly higher in the aprepitant group (72.7% [n = 260] v 52.3% in the standard therapy group [n = 260]), as were the percentages on day 1, and especially on days 2 to 5 (P <.001 for all three comparisons). CONCLUSION: Compared with standard dual therapy, addition of aprepitant was generally well tolerated and provided consistently superior protection against CINV in patients receiving highly emetogenic cisplatin-based chemotherapy.  相似文献   
42.
The prognosis of Marfan syndrome in both adult and pediatric patients is primarily related to the cardiovascular complications. In infantile Marfan syndrome, although involvement of the mitral valve is the most frequently encountered cardiovascular lesion, the aortic root can be more worrisome because of its excessive dilatation, leading to aortic insufficiency or dissection. If the role of elective surgery is relatively well defined for adult patients, it is still debated during childhood. We report two patients, aged 22 months and 5 years, each presenting an aortic root aneurysm related to Marfan syndrome, and each treated with the Bentall procedure without specific age-related mortality or morbidity. These two patients experienced normal growth and were free of any complication for a follow-up period of 8 and 2 years, respectively. More than an absolute value of the aortic root dimension, it is the conjunction of the rate of progression of the aortic root dilatation, the degree and the duration of the aortic valve regurgitation, and its resulting left ventricular dysfunction that must be taken into consideration in choosing the surgical option.  相似文献   
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The in vitro effects of myotoxin III (MT-III), an Asp-49 catalytically-active phospholipase A(2), and myotoxin II (MT-II), a catalytically-inactive Lys-49 variant, isolated from Bothrops asper snake venom, on phagocytosis and production of hydrogen peroxide (H(2)O(2)) by thioglycollate-elicited macrophages were investigated. MT-II and MT-III were cytotoxic to mouse peritoneal macrophages at concentrations higher than 25 microg/ml. At non-cytotoxic concentrations, MT-II stimulated Fcgamma, complement, mannose and beta-glucan receptors-mediated phagocytosis, whereas MT-III stimulated only the mannose and beta-glucan receptors-mediated phagocytosis. Moreover, both myotoxins induced the release of H(2)O(2) by thioglycollate-elicited macrophages, MT-III being the most potent stimulator. MT-II induced the release of H(2)O(2) only at a concentration of 3.2 microg/ml (130% increment) while MT-III induced this effect at all concentrations tested (0.5-2.5 microg/ml; average of 206% increment). It is concluded that, at non-cytotoxic concentrations, MT-II and MT-III activate defense mechanisms in macrophages up regulating phagocytosis, mainly via mannose and beta-glucan receptors, and the respiratory burst.  相似文献   
44.
Bothrops asper venom (BaV) causes systemic and local effects characterized by an acute inflammatory reaction with accumulation of leukocytes and release of endogenous mediators. In this study, the effects of BaV on the release of the cytokines IL-1, IL-6 and TNF-alpha and the eicosanoids LTB4 and TXA2 in the peritoneal cavity of mice were analyzed. We also investigated the participation of beta2 integrin chain, l-selectin, LFA-1, ICAM-1 and PECAM-1 adhesion molecules in the BaV-induced leukocyte accumulation. Levels of proinflammatory cytokines IL-6 and TNF-alpha, as well as eicosanoids LTB4 and TXA2 were significantly increased after BaV injection (250 microg/kg), whereas no increment in IL-1 was observed. Anti-mouse l-selectin, LFA-1, ICAM-1, PECAM-1 and beta2 integrin chain monoclonal antibodies resulted in a reduction of neutrophil accumulation induced by BaV injection compared with isotype-matched control injected animals. These data suggest that BaV is able to induce the activation of leukocytes and endothelium to express adhesion molecules involved in the recruitment of neutrophils into the inflammed site. Furthermore, these results showed that BaV induces the release of cytokines and eicosanoids in the local of the venom injection; these inflammatory mediators may be important for the initiation and amplification of the inflammatory reaction characteristic from Bothrops sp envenomation.  相似文献   
45.
Ethanolic extracts from the kernels of ripe fruits from the Indian Lilac Melia azedarach and from the well-known Neem tree, Azadirachta indica were assayed against larvae of Aedes aegypti, the mosquito vector of dengue fever. The lethality bioassays were carried out according to the recommendations of the World Health Organization. Extracts were tested at doses ranging from 0.0033 to 0.05 g% in an aqueous medium for 24 and 48 h, at 25 or 30 °C, with or without feeding of the larvae. LC50, LC95 and LC99 were determined. Both seed extracts proved lethal for third to fourth instar larvae. Non-fed A. aegypti larvae were more susceptible to Azadirachta extracts at both temperatures. Under a more realistic environmental situation, namely with fed larvae at 25 °C, the death rates caused by the Melia extract were higher, although at 30 °C the extract of Azadirachta had an even higher lethality. Inter allia, the LC50 values for the crude extracts of these two members of the Meliaceae ranged from 0.017 to 0.034 g% while the LC99 values ranged from 0.133 to 0.189 g%. Since no downstream processing was undertaken to purify the active agents in the extracts, our findings seem very promising, suggesting that it may be possible to increase the larvicidal activity further by improving the extraction and the fractionation of the crude limonoids, for instance removing the co-extracted natural fats.  相似文献   
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The purpose of this study was to evaluate the association between ATM, TP53 and MDM2 polymorphisms in prostate cancer patients and morbidity after radiotherapy. The presence of ATM (rs1801516), TP53 (rs1042522, rs1800371, rs17878362, rs17883323, and rs35117667), and MDM2 (rs2279744) polymorphisms was assessed by direct sequencing of PCR fragments from 48 patients with histologically proven prostate adenocarcinoma and treated with external beam radiation. The side effects were classified according to the Radiation Therapy Oncology Group (RTOG) score. The results showed no association between clinical characteristics and the development of radiation toxicities (P > 0.05). The C>T transition in the position 16273 (intron 3) of TP53 (rs35117667) was significantly associated with the risk of acute skin toxicity (OR: 0.0072, 95% CI 0.0002–0.227, P = 0.003). The intronic TP53 polymorphism at position 16250 (rs17883323) was associated with chronic urinary toxicity (OR: 0.071, 95%CI 0.006–0.784, P = 0.032). No significant associations were found for the remaining polymorphisms (P > 0.05). The results show that clinical characteristics were not determinant on the developing of radiation sensitivity in prostate cancer patients, and intronic TP53 polymorphisms would be associated with increased acute and chronic radiation toxicities. These observations corroborate the importance of investigating the genetic profile to predict adverse side effects in patients undergoing radiotherapy.  相似文献   
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Fetal skin has the intrinsic capacity for wound healing, which is not correlated with the intrauterine environment. This intrinsic ability requires biochemical signals, which start at the cellular level and lead to secretion of transforming factors and expression of receptors, and specific markers that promote wound healing without scar formation. The mechanisms and molecular pathways of wound healing still need to be elucidated to achieve a complete understanding of this remodeling system. The aim of this paper is to discuss the main biomarkers involved in fetal skin wound healing as well as their respective mechanisms of action.  相似文献   
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