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Melo AM de Carvalho RA Figueiredo JF Vannucchi H Jordão Junior A Rodrigues ML 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2004,98(8):485-488
In order to evaluate the association between serum vitamin A levels and ocular lesions attributable to non-complicated malaria, 200 patients seen consecutively at the Malaria Outpatient Clinic of FUNASA, Manaus, Amazonas, Brazil were included in this study. Ophthalmologic examination consisted of indirect binocular ophthalmoscopy under medicamentous mydriasis, biomicroscopy with a portable slit lamp and measurement of central visual acuity. Vitamin A serum concentration was determined by HPLC, and deficiency was defined as serum values equal to or lower than 0.35 micromol/l. Serum vitamin A values between 0.36 and 0.70 micromol/l were considered as marginal levels. Hypovitaminosis A (=0.70 micromol/l serum levels) was observed in 33% (66/200) of the patients. Ocular lesions were associated with serum levels =0.35 micromol/l (P < 0.001). Vitamin A deficiency was more frequent in patients with high parasitaemia (P = 0.029) and their first episode of malaria (P = 0.016). None of the patients showed clinical or ophthalmologic signs attributable to hypovitaminosis A. 相似文献
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Jordão CO Vichnewski W de Souza GE Albuquerque S Lopes JL 《Phytotherapy research : PTR》2004,18(4):332-334
The ethyl acetate extract from leaves plus inflorescences of L. salicifolia showed significant trypanocidal activity against trypomastigote forms of T. cruzi, which was due to the flavonoid quercetin-7,3',4'-trimethyl ether and the sesquiterpenoid lychnopholic acid. Despite the use of some species of Lychnophora in folk medicine for pain relief, crude extracts from L. salicifolia Mart. showed no antinociceptive activity in the mouse writhing test. 相似文献
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Molecular classifiers for gastric cancer and nonmalignant diseases of the gastric mucosa 总被引:9,自引:0,他引:9
Meireles SI Cristo EB Carvalho AF Hirata R Pelosof A Gomes LI Martins WK Begnami MD Zitron C Montagnini AL Soares FA Neves EJ Reis LF 《Cancer research》2004,64(4):1255-1265
High incidence of gastric cancer-related death is mainly due to diagnosis at an advanced stage in addition to the lack of adequate neoadjuvant therapy. Hence, new tools aimed at early diagnosis would have a positive impact in the outcome of the disease. Using cDNA arrays having 376 genes either identified previously as altered in gastric tumors or known to be altered in human cancer, we determined expression signature of 99 tissue fragments representing normal gastric mucosa, gastritis, intestinal metaplasia, and adenocarcinomas. We first validated the array by identifying molecular markers that are associated with intestinal metaplasia, considered as a transition stage of gastric adenocarcinomas of the intestinal type as well as markers that are associated with diffuse type of gastric adenocarcinomas. Next, we applied Fisher's linear discriminant analysis in an exhaustive search of trios of genes that could be used to build classifiers for class distinction. Many classifiers could distinguish between normal and tumor samples, whereas, for the distinction of gastritis from tumor and for metaplasia from tumor, fewer classifiers were identified. Statistical validations showed that trios that discriminate between normal and tumor samples are powerful classifiers to distinguish between tumor and nontumor samples. More relevant, it was possible to identify samples of intestinal metaplasia that have expression signature resembling that of an adenocarcinoma and can now be used for follow-up of patients to determine their potential as a prognostic test for malignant transformation. 相似文献
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Figueras-Aloy J Jordín Y Rodraguez-Miguélez JM Jiménez W Botet F Carbonell X Jiménez R 《American journal of perinatology》2003,20(3):137-145
The objective of this study is to determine expired nitric oxide (expNO) in the first 3 days of life in relation to: hours of life, gestational age, type of labor, and risk of perinatal infection. Our hypothesis has been that expNO increases in newborns with high risk of perinatal infection. Total expNO was measured in 166 newborns: 108 healthy (63 full-term and 45 preterm), 30 with low risk of perinatal infection, and 28 with high risk of perinatal infection treated with antibiotics but without positive hemoculture. Expired gas was collected using a face mask and NO concentration was determined by chemiluminescence. Total expNO neither correlated with gestational age, birth weight or serum NOx, nor changed after cesarean section, but was related to hours of life. Total expNO in the < or = 36-hour subgroups (median, interquartile range) was higher in the high-risk perinatal infection newborns ( n = 8; 5.33 (4.5-7.2) nL/min*Kg) than in healthy newborns ( n = 59; 4.13 (3.5-4.7) nL/min*kg) or low-risk perinatal infection newborns ( n = 18; 3.99 (3.4-4.7) nL/min*kg). In the 37 to 72-hour subgroups there were also differences between healthy newborns ( n = 49; 4.68 (4.1-5.3) nL/min*kg) or low-risk perinatal infection newborns on the one hand ( n = 12, 4.55 (3.9-5.2) nL/min*kg) and high risk perinatal infection newborns on the other ( n = 20; 9.69 (7.6-11.1) nL/min*kg). Then, total expNO increased in newborns with high risk of perinatal infection, regardless of hours of life. 相似文献
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Teas of Bidens pilosa and Mikania glomerata are popularly consumed to medicinal ends. The capacity to induce DNA damages and mutagenic effects of these teas were evaluated, in vitro, on HTC cells, with comet assay and micronucleus test. The teas tested at various doses were prepared differently: infusion of Mikania glomerata (IM) and Bidens pilosa (IB), macerate of Mikania glomerata in 80% ethanol (MM80) and decoction of Bidens pilosa (DB). In IM and MM80, the quantity of coumarin was determined by high-performance liquid chromatography (HPLC) with UV detection. Methylmethanesulfonate was utilized as positive control, phosphate-buffered saline as negative control, 80% ethanol as solvent control and 2-aminoanthracene as drug metabolism control. The comet assay demonstrated genotoxic effects for both plants. The genotoxic potential of IB was upper than DB, showing dose-response. In the MN test, excepting IM 40 microL/mL, all treatments was not mutagenic. The effects did not show direct relation with cumarin quantity present in IM and MM80. The results demonstrated DNA damages at the highest concentrations of alcoholic macerate (10 and 20 microL/mL) and infusion of Mikania glomerata (20 and 40 microL/mL) and of Bidens pilosa infusion (40 microL/mL). Thus, both dose and preparation-form suggest caution in the phytotherapeutic use of these plants. 相似文献
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Jaqueline J. Muniz Riccardo Lacchini Jonas T. C. Sertório Alceu A. Jordão Jr. Yuri T. D. A. Nobre Silvio Tucci Jr. Antônio C. P. Martins Jose E. Tanus-Santos 《Naunyn-Schmiedeberg's archives of pharmacology》2013,386(9):805-811
Erectile dysfunction (ED) is a multifactorial disease associated with vascular dysfunction, low nitric oxide (NO) bioavailability, and oxidative stress. However, it is not known whether low NO bioavailability and oxidative stress affect the responsiveness of ED patients to sildenafil. We tested this hypothesis by studying 28 healthy subjects (control group), 26 patients with ED without comorbidities (ED group), and 18 patients with ED and diabetes mellitus (ED/DM group). The International Index for Erectile Function (IIEF) questionnaire was used to assess the erectile function of all participants, and their responsiveness to sildenafil was assessed as the percentage of change in the five-item version of IIEF score before and after sildenafil treatment. Levels of whole blood nitrite, antioxidants markers (ferric reducing ability of plasma (FRAP) and reduced glutathione), and oxidative stress markers (thiobarbituric acid reactive substance and protein carbonyl) were determined. We found a negative correlation between whole blood nitrite levels and the responses to sildenafil in both ED groups (P?<?0.05). FRAP correlated negatively with the responses to sildenafil in the ED/DM group (P?<?0.05). No other significant associations were found. Our findings show evidence that low NO bioavailability is associated with better responses to sildenafil in patients with ED (with or without DM). 相似文献