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991.
992.
Angélica Nogueira-Rodrigues Cláudio C do Carmo Célia Viegas Felipe Erlich Cláudia Camis?o Karina Font?o Roberta Lima Daniel Herchenhorn Renato G Martins Giulliana M Moralez Isabele A Small Carlos G Ferreira 《Clinical cancer research》2008,14(19):6324-6329
PURPOSE: This phase I trial was aimed to determine the maximum tolerated dose and related toxicity of erlotinib (E) when administered concurrently with standard chemoradiation (CRT) for cervical cancer. EXPERIMENTAL DESIGN: In a modified Fibonacci design, the study aimed to study three cohorts of at least three patients receiving escalating doses of erlotinib (50/100/150 mg) combined with cisplatin (40 mg/m(2), weekly, 5 cycles) and radiotherapy (external beam 4,500 cGy in 25 fractions, followed by 4 fractions/600 cGy/weekly of brachytherapy) in squamous cell cervical carcinoma patients, stage IIB to IIIB. RESULTS: Fifteen patients were enrolled, 3 at dose level (DL) 50 mg, 4 at DL 100 mg, and 8 at DL 150 mg. Patients presented median age 47 (36-59), stage IIB (46.2%) and IIIB (53.8%). Overall, E+CRT was well-tolerated. Three patients did not complete the planned schedule. One patient at DL 100 mg withdrew informed consent due to grade 2 rash; at DL 150 mg, 1 patient presented Raynaud's Syndrome and had C interrupted, and another patient presented grade 4 hepatotoxicity. The latter was interpreted as dose limiting toxicity and a new cohort of 150 mg was started. No further grade 4 toxicity occurred. Grade 3 toxicity occurred in 6 cases: diarrhea in 3 patients, rash in 2 patients, and leukopenia in 1 patient. E+CRT did not lead to limiting in-field toxicity. CONCLUSIONS: E+CRT is feasible to locally advanced squamous cell cervical cancer and is well tolerated. The maximum tolerated dose has been defined as 150 mg. To the best of our knowledge, this is the first report of a combination of erlotinib, cisplatin, and pelvic radiotherapy. 相似文献
993.
The interleukin-8-251*T/*A polymorphism is not associated with risk for gastric carcinoma development in a Portuguese population. 总被引:2,自引:0,他引:2
Paulo Canedo Abel J Castanheira-Vale Nuno Lunet Fábio Pereira Céu Figueiredo Lydie Gioia-Patricola Federico Canzian Herculano Moreira Gianpaolo Suriano Henrique Barros Fátima Carneiro Raquel Seruca José C Machado 《European journal of cancer prevention》2008,17(1):28-32
It has been demonstrated that polymorphisms within inflammation-related genes are associated with risk of gastric carcinoma in Helicobacter pylori-infected individuals. Recently, several studies have reported conflicting results regarding the association between the interleukin (IL)8-251*T/*A polymorphism and risk of gastric carcinoma. In this study, we performed a case-control analysis, including 693 controls, 187 chronic gastritis cases and 333 gastric carcinoma cases, to determine the association between the IL8-251 polymorphism and risk of chronic gastritis and gastric carcinoma in the northern Portugal population. We found no significant association between the IL8-251 polymorphism and increased risk of chronic gastritis or gastric carcinoma, in agreement with that reported in other populations of white origin. The retrospective analysis of published data shows that the association between the IL8-251 polymorphism and risk of gastric carcinoma tends to be reproducible in populations of Asian origin. The estimated effect of the polymorphism under analysis was not significantly different in subgroups of gastric carcinoma cases defined by histologic type and anatomic site of the tumours, and by sex and age of the participants. In conclusion our results indicate that although the IL8-251 polymorphism might be a relevant host susceptibility factor for gastric carcinoma development, this association is likely to be ethnic-specific. 相似文献
994.
Antioxidant properties, total phenols and pollen analysis of propolis samples from Portugal 总被引:1,自引:1,他引:1
Leandro Moreira Luís G Dias José Alberto Pereira Leticia Estevinho 《Food and chemical toxicology》2008,46(11):3482-3485
Pollen analysis, total phenols content and antioxidant activity were studied for the first time in Portuguese propolis samples from Bornes and Fundão regions. Total phenols content was determined by colorimetric assay and their amount was of 329 mg/g of GAE in Bornes sample and 151 mg/g of GAE in Fundão propolis. The antioxidant capacity of propolis extracts was assessed through the scavenging effects on DPPH (2,2-diphenyl-1-picrylhydrazyl) and reducing power of iron (III)/ ferricyanide complex assays. A concentration-dependent antioxidative capacity was verified in DPPH and reducing power assays. Low values of EC50 on DPPH scavenging assay were obtained for Bornes and Fundão propolis (of 6.22 μg/mL and 52.00 μg/mL, respectively). For reducing power the values were 9.00 μg/mL, for Bornes propolis, and 55.00 μg/mL, for Fundão propolis. The high activity of propolis from Bornes could be related with their different pollen composition. The results obtained indicate that Portuguese propolis is an important source of total phenols showing antioxidant properties that could be beneficial for human health. 相似文献
995.
M Rudnicki M M Silveira T V Pereira M R Oliveira F H Reginatto F Dal-Pizzol J C F Moreira 《Food and chemical toxicology》2007,45(4):656-661
The leaf extract of Passiflora alata Dryander (P. alata) has been demonstrated to possess antioxidant activity in vitro. The aim of this study was to investigate the effects of P. alata leaf extract pretreatment on carbon tetrachloride-treated rats. Male Wistar rats were randomly allocated into four groups: group 1 (control - vehicle), group 2 and 3 (P. alata extract - 1 and 5mg/kg, respectively) and group 4 (trolox - 0.18mg/kg). Rats received daily pretreatment by oral gavage for 30 days followed by a single dose of CCl(4) (3ml/kg i.p. in vegetable oil) on the 30th day and were killed after 6h. The pretreatment with the P. alata extract provided significant protection to liver, evidenced by lower degree of necrosis, decreased lipid peroxidation (TBARS) and higher catalase and superoxide dismutase activities. Additionally, pretreated-rats with P. alata (5mg/kg) showed significantly decreased cardiac TBARS levels. Our results indicate that a low oral dose of P. alata leaf extract has both hepato and cardioprotective effects on rats treated with CCl(4). 相似文献
996.
J L Mazzei D N da Silva V Oliveira R Z Hosomi R R do Val C B Pestana I Felzenszwalb 《Food and chemical toxicology》2007,45(4):643-648
In the present work, three commercial acid (pH 3.5-4) pyrogallol-containing hair gels, SunSet Alizador Negro (two formulations) and Embelleze Henê Gel, were tested for mutagenicity using two well-established assays. In the Salmonella mutagenicity assay using 648-5000 microg/plate of cosmetic samples, none of the samples reached a 2-fold increase in revertants relative to the controls. Both in the absence and in the presence of S9, the dose-response relation in strains TA98, TA100, TA102, TA1535, and TA1537 was not significant (p>0.01). In the mouse bone marrow micronucleus assay, 10 Swiss male mice were orally administered 2000 mg/kg of sample per body weight/day. The ratio between polychromatic and normochromatic erythrocytes as well as the presence of micronuclei in bone marrow cells were determined. Equal numbers of micronucleated polychromatic erythrocytes were detected between the cells of each treated group and the negative control, using ANOVA and chi-square analyses. Thus, none of the products induced mutagenesis in either assay. Previous studies have shown pyrogallol is mutagenic in various test systems, including Salmonella. However studies have also shown that acidic conditions may repress the reactive-oxygen species (ROS) produced by pyrogallol, and ROS is considered the primary mechanism for the mutagenicity of pyrogallol. Consistent with this are our results, which show that acidic, commercially available pyrogallol-containing hair gels are neither mutagenic in Salmonella nor induce micronuclei in mouse bone marrow in vivo. 相似文献
997.
Vikas Kumar Mool Raj Kural B.M.J. Pereira Partha Roy 《Food and chemical toxicology》2008,46(12):3563-3570
Mentha spicata Labiatae, commonly known as spearmint, can be used for various kinds of illnesses in herbal medicines and food industries. One of the prominent functions of this plant extract is its anti-androgenic activity. The present study investigated the probable correlation between oxidative stress in hypothalamic region and anti-androgenic action of this plant’s aqueous extract on rats. Decreased activities of enzymes like superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase in hypothalamus of treated rats indicated spearmint induced oxidative stress. Further RT-PCR and immunoblot analysis demonstrated the decreased expression of some of the steroidogenic enzymes, cytochrome P450scc, cytochrome P450C17, 3β-Hydroxysteroid dehydrogenase (3β-HSD), 17β-Hydroxysteroid dehydrogenase (17β-HSD) and other related proteins like, steroidogenic acute regulatory protein, androgen receptor and scavenger receptor class B-1. Further, in vitro enzyme assays demonstrated depressed activities of testicular 3β-HSD and 17β-HSD enzymes. Histopathology indicated a decreased sperm density in cauda epididymis and degeneration of ductus deference. Our study suggested that spearmint probably induced oxidative stress in hypothalamus resulting in decreased synthesis of LH and FSH which in turn down-regulated the production of testicular testosterone through the disruption of a number of intermediate cascades. 相似文献
998.
Rosana Franco Andreia C Santos Harrison F do Nascimento Carolina Souza-Machado Eduardo Ponte Adelmir Souza-Machado Sebastião Loureiro Maurício L Barreto Laura C Rodrigues Alvaro A Cruz 《BMC public health》2007,7(1):82
Background
Asthma is one of the most common chronic diseases and a major economical burden to families and health systems. Whereas efficacy of current therapeutical options has been clearly established, cost-effectiveness analysis of public health interventions for asthma control are scarce. 相似文献999.
Garvey Chilopora Caetano Pereira Francis Kamwendo Agnes Chimbiri Eddie Malunga Staffan Bergström 《Human resources for health》2007,5(1):17-6
Background
Clinical officers perform much of major emergency surgery in Malawi, in the absence of medical officers. The aim of this study was to validate the advantages and disadvantages of delegation of major obstetric surgery to non-doctors. 相似文献1000.
Takizawa PA Vale RD 《Proceedings of the National Academy of Sciences of the United States of America》2000,97(10):5273-5278
In Saccharomyces cerevisiae, mRNA encoding the cell-fate determinant Ash1p is localized to the distal tip of daughter cells. Five SHE genes are required for proper Ash1 mRNA localization, one of which encodes the myosin Myo4p. We show that three of the five She proteins, She2p, She3p, and Myo4p, colocalize with Ash1 mRNA in vivo and coimmunoprecipitate with Ash1 mRNA from cell extracts. We also find that She3p binds to Myo4p in the absence of RNA and She2p is required for binding She3p-Myo4p to Ash1 mRNA. These results suggest that She3p acts as an adapter protein that docks the myosin motor onto an Ash1-She2p ribonucleoprotein complex. 相似文献