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981.
Glasnović M Bosnjak I Vcev A Soldo I Kosuta M Lenz B Glasnović-Horvatić E Soldo-Butković S Mićunović N 《Collegium antropologicum》2007,31(1):173-177
The aim of the research was to show our diagnostic and therapeutic experience with antiphospholipid syndrome (APS) in pregnant women. 36 pregnant women suspect on APS were included in the study: 32 with primary antiphospholipd syndrome (PAPS) and 4 with secondary antiphospholipid syndrome (SAPS). All pregnant women received low-molecular-weight-heparin (LMWH) and low dose aspirin (LDA) therapy. Control group represented 26 women with SAPS and previous bad reproductive anamnesis. Average pregnancy lasted 37.06 +/- 0.707 weeks. LMWH and LDA therapy was successful in 97.22%. Lupus anticoagulant (LA) was found to be more frequent in PAPS group (71.87%). Anticardiolipin antibodies (aCL) were found to be more frequent in SAPS (26.66%). For three patients (3.37%), PAPS was diagnosed due to a fact that they had positive antibeta2-glycoproteinl (antibeta-GP1). To make APS diagnosis, it is of great importance to search for all antiphospholipid antibodies. LMWH and low dose of acetylsalicylic acid should be the first choice therapy. 相似文献
982.
Ferreira AJ Jacoby BA Araújo CA Macedo FA Silva GA Almeida AP Caliari MV Santos RA 《American journal of physiology. Heart and circulatory physiology》2007,292(2):H1113-H1119
The nonpeptide AVE-0991, which has been reported as a selective ligand for the angiotensin-(1-7) [ANG-(1-7)] receptor Mas, has actions similar to those attributed to the cardioprotective product of the renin-angiotensin system, ANG-(1-7). In this study, we evaluated the cardiac effects of AVE-0991 in normal and infarcted male Wistar rats. Myocardial infarction was induced by left coronary artery ligation. At the end of the treatment, the Langendorff technique was used to analyze cardiac function. Left ventricle serial sections were dyed with Gomori trichrome stain to quantify the infarcted area. In normal hearts, AVE-0991 produced a significant decrease in perfusion pressure and an increase in systolic tension, rate of tension rise and fall (+/-dT/dt), and heart rate. These effects were completely blocked by the perfusion of the hearts with a solution containing the selective ANG-(1-7) antagonist A-779. N(G)-nitro-l-arginine methyl ester treatment abolished the AVE-0991-induced vasodilation in isolated hearts. AVE-0991 significantly attenuated the decrease in systolic tension (sham operated, 13.00 +/- 1.02 g; infarction, 7.18 +/- 0.66 g; AVE treated, 9.23 +/- 1.05 g, n = 5), +dT/dt, -dT/dt, and heart rate induced by myocardial infarction. Infarction-induced vasoconstriction was completely prevented by AVE-0991 treatment. Furthermore, AVE-0991 significantly decreased the infarcted area (6.98 +/- 1.01 vs. 3.94 +/- 1.04 mm(2) in AVE-treated rats). These data indicate that the compound AVE-0991 produces beneficial effects in isolated perfused rat hearts involving the ANG-(1-7) receptor Mas and the release of nitric oxide. In addition, our results indicate that AVE-0991 attenuates postischemic heart failure. 相似文献
983.
984.
Matos MH Lima-Verde IB Luque MC Maia JE Silva JR Celestino JJ Martins FS Báo SN Lucci CM Figueiredo JR 《Zygote (Cambridge, England)》2007,15(2):173-182
The aims of the present study were to investigate the effects of follicle-stimulating hormone (FSH) on survival, activation and growth of caprine primordial follicles using histological and ultrastructural studies. Pieces of caprine ovarian cortex were cultured for 1 or 7 days in minimum essential medium (MEM - control medium) supplemented with different concentrations of FSH (0, 10, 50 or 100 ng/ml). Small fragments from non-cultured ovarian tissue and from those cultured for 1 or 7 days in a specific medium were processed for classical histology and transmission electron microscopy (TEM). Additionally, effects of FSH on oocyte and follicle diameter of cultured follicles were evaluated. The results showed that the lowest percentage of normal follicles was observed after 7 days of culture in control medium. After 1 day of culture, a higher percentage of growing follicles was observed in the medium supplemented with 50 ng/ml of FSH. In the presence of 10 and 50 ng/ml of FSH, an increase in diameter of both oocyte and follicle on day 7 of culture was observed. TEM showed ultrastructural integrity of follicles after 1 day of culture in MEM and after 7 days in MEM plus 50 ng/ml FSH, but did not confirm the integrity of those follicles cultured for 7 days in MEM. In conclusion, this study demonstrated that FSH at concentration of 50 ng/ml not only maintains the morphological integrity of 7 days cultured caprine preantral follicles, but also stimulate the activation of primordial follicles and the growth of activated follicles. 相似文献
985.
da Silva LE Joussef AC Pacheco LK da Silva DG Steindel M Rebelo RA Schmidt B 《Bioorganic & medicinal chemistry》2007,15(24):7553-7560
In the present paper 12 N-quinolin-8-yl-arylsulfonamides synthesized by coupling 8-aminoquinolines with various arylsulfonylchlorides were assayed in vitro against Leishmania amazonensis, Leishmania chagasi and Trypanosoma cruzi strains. This series of new compounds were found to be selective for Leishmania spp. promastigote and amastigote forms. The most active compound was the N-(8-quinolyl)-3,5-difluoro-benzenesulfonamide 10 with an IC50 against L. amazonensis and L. chagasi of 2.12 and 0.45 μM, respectively. The less cytotoxic biphenyl derivative 7 was very effective against intracellular L. amazonensis with a reduction of macrophage cell infection of 82.1% at 25 μM. In addition, a copper complex 17 of an inactive ligand was readily synthesized and showed high leishmanicidal and trypanocidal activity against both extra and intracellular forms. 相似文献
986.
da Silva Júnior EN de Souza MC Pinto AV Pinto Mdo C Goulart MO Barros FW Pessoa C Costa-Lotufo LV Montenegro RC de Moraes MO Ferreira VF 《Bioorganic & medicinal chemistry》2007,15(22):7035-7041
Several arylamino derivatives of nor-beta-lapachone were synthesized in moderate to high yields and found to show very potent cytotoxicity against six neoplastic cancer cells: SF-295 (central nervous system), HCT-8 (colon), MDAMB-435 (breast), HL-60 (leukaemia), PC-3 (prostate), and B-16 (murine melanoma), with IC(50) below 1 microg/mL. Their cytotoxicities were compared to doxorubicin and with their synthetic precursors, beta-lapachone and nor-beta-lapachone. The activity against a normal murine fibroblast L-929 showed that some of the compounds were selective against cancer cells. The absence of hemolytic activity (EC(50)>200 microg/mL), performed with erythrocyte suspensions, suggests that the cytotoxicity of the compounds was not related to membrane damage of mouse erythrocytes. For comparison purposes, one isomeric compound based on nor-alpha-lapachone was also synthesized and showed lower activity than the related ortho-derivative. The modified arylamino quinones appear as interesting new lead compounds in anti-cancer drug development. 相似文献
987.
de Araújo MV Vieira EK Lázaro GS de Souza Conegero L Ferreira OP Almeida LS Barreto LS da Costa NB Gimenez IF 《Bioorganic & medicinal chemistry》2007,15(17):5752-5759
The inclusion complexation of pyrimethamine in 2-hydroxypropyl-beta-cyclodextrin has been investigated by 2D (1)H NMR, FTIR and UV/visible spectroscopy and also by molecular modelling methods (AM1, PM3, MM3). From the phase-solubility diagram a linear increase was observed in pyrimethamine aqueous solubility in the presence of 2-hydroxypropyl-beta-cyclodextrin, evidencing the formation of a soluble inclusion complex. According to the continuous variation method (Job's plot) applied to fluorescence measurements, a 1:1 stoichiometry has been proposed for the complex. Concerning the structure of the complex, a Cl-in orientation of pyrimethamine in the 2-hydroxypropyl-beta-cyclodextrin cavity has been proposed from the theoretical calculations, being confirmed by two-dimensional (1)H NMR spectroscopy (ROESY). The thermal behaviour has also been studied, providing complementary evidences of complex formation. 相似文献
988.
Eliseu José G. Pereira Leandro Bacci Terezinha Maria C. Della Lucia Ézio M. Silva Flávio L. Fernandes 《Biocontrol Science and Technology》2007,17(5):441-455
The natural mortality of the coffee leafminer, Leucoptera coffeella (Guérin-Méneville) was investigated in three strata of coffee plant canopy for three seasons through construction and analysis of ecological life tables. Mortality of the leafminer was similar on all thirds of the canopy. Total mortality of immature stages was 95%, with 38.5, 43.8 and 12.7% occurring during egg, larval, and pupal stages. Rainfall killed 39.3% of eggs and larvae, and together with egg inviability (16.3%) and Vespidae (11.3%), were the highest mortality factors. Six wasp parasitoids caused 8% of larval mortality. Egg and larva were the critical stages. Variation in mortality was primarily associated with egg inviability, rainfall, and parasitism by Horismenus sp. (Hymenoptera: Eulophidae). Physiological disturbances during molting and metamorphosis also contributed for fluctuations in mortality of the leafminer. Tactics of integrated pest management to enhance natural mortality of the leafminer while conserving or augmenting the action of natural enemies are discussed. 相似文献
989.
We studied the life-history of the Sierra Madre sparrow (Xenospiza baileyi) in a subalpine grassland-agriculture mosaic south of Mexico City. From March to early September 1999 we captured and color-banded
53 adults with mist-nets and mapped the breeding territories of 21 males. We again mapped territories in the same spot in
April and May 2000. The number of breeding territories was found to be the same in the two consecutive years and interannual
survivorship was found to be relatively high. Breeding territories were restricted to the bunchgrass-covered areas. We used
the density of territories and the amount of remaining habitat to estimate a total population size of 5,380–6,150 adults for
this species. Using this and other recent data, we recommend raising the Sierra Madre sparrow to the status of critically
endangered using BirdLife International criteria. 相似文献
990.
Claudia M. Jacobi Flávio F. do Carmo Regina C. Vincent João R. Stehmann 《Biodiversity and Conservation》2007,16(7):2185-2200
Mountain areas are recognized centres of endemism and diversity on account of their isolation and altitudinal diversity. In
tropical regions, mountain tops usually stand as islands of xeric vegetation among mesophytic assemblages. Unlike the vegetation
growing on other rock outcrops lithologies, such as inselbergs (granite/gneiss) or campos rupestres (quartz/arenite), ironstone outcrop plant communities still lack systematic studies in Brazil. These outcrops (locally known
as canga) share most of the characteristics of other rock outcrops, such as isolation and edapho-climatic harshness, but differ in
that they are the object of opencast mining, and thus subjected to irrecoverable degradation. In addition, they are expected
to harbour metal-tolerant and hyperaccumulator plant species. A botanical survey of two ironstone outcrop locations in the
most important mining region of southeastern Brazil, the Iron Quadrangle, revealed a high within-site (138 and 160 species
per site), and between-site diversity (only 27% of common species), totaling 64 families and 234 species among basal families
and eudicots (154 species), monocots (68 species), and ferns (12 species). Canga crusts are rich in dicots, several of which play an important role in community structuring, together with the more usual
monocot aggregations. Distinct plant communities are found associated to different microhabitats within the iron crust, depending
primarily on the amount of soil and moisture retention in the different microtopographies. The environmental uniqueness, high
diversity, lack of studies and rapid destruction of these ecosystems pose an immediate challenge for their conservation. 相似文献