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1.
The Cerrado, the largest savanna region in South America, is located in central Brazil. Cerrado physiognomies, which range from savanna grasslands to forest formations, combined with the highly weathered, acidic clay Cerrado soils form a unique ecoregion. In this study, high-throughput sequencing of ribosomal RNA genes was combined with shotgun metagenomic analysis to explore the taxonomic composition and potential functions of soil microbial communities in four different vegetation physiognomies during both dry and rainy seasons. Our results showed that changes in bacterial, archaeal, and fungal community structures in cerrado denso, cerrado sensu stricto, campo sujo, and gallery forest soils strongly correlated with seasonal patterns of soil water uptake. The relative abundance of AD3, WPS-2, Planctomycetes, Thermoprotei, and Glomeromycota typically decreased in the rainy season, whereas the relative abundance of Proteobacteria and Ascomycota increased. In addition, analysis of shotgun metagenomic data revealed a significant increase in the relative abundance of genes associated with iron acquisition and metabolism, dormancy, and sporulation during the dry season, and an increase in the relative abundance of genes related to respiration and DNA and protein metabolism during the rainy season. These gene functional categories are associated with adaptation to water stress. Our results further the understanding of how tropical savanna soil microbial communities may be influenced by vegetation covering and temporal variations in soil moisture.  相似文献   
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Mixed model methodology under univariate and bivariate animal models was used to estimate genetic parameters of scrotal circumference (SC) unadjusted (h2U) and adjusted (h2A) for body weight, from field data on 875 Nellore males sired by 80 bulls. The models included random effect of animal, the fixed effects of age of dam, year of birth, and month and year of measurement, and the covariate age of the animal. In addition, one of the models also included the covariate body weight. Using univariate models, SC estimates of h2U were 0.18, 0.65, 0.77 and 0.60, and of h2A they were 0.15, 0.60, 0.71 and 0.50, at 9, 12, 18 and 24 m.o. of age, respectively. Bivariate estimates of heritability ranged from 0.18 to 0.77 for h2U, and from 0.13 to 0.70 for h2A. The results suggest that it would be better to consider unadjusted SC rather than adjusted SC in selection programs. Bivariate body weight estimates of heritability ranged from 0.15 to 0.45. Genetic correlations between SC and body weight ranged from 0.58 to 0.71 when body weight was not included in the model, and from 0.33 to 0.64 when body weight was included. These results suggest that simultaneous selection for body weight and SC is possible in Nellore cattle.  相似文献   
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Objectives: Although emerging data suggest that zoledronic acid (Zol) may have different anti‐tumour activities against a broad range of cancers, its effects on lung cancer remain largely unknown. The aim of this study was to evaluate in vitro the anti‐tumoural and anti‐angiogenetic effect of zoledronic acid in non‐small‐cell lung cancer (NSCLC) cells. Material and methods: We treated A549 NSCLC cells with zoledronic acid to investigate survival, cell cycle activity, anti‐angiogenic activity and apoptotic responses to it. Results: We observed that highest Zol concentration (100 μm ) caused arrest in G1 phase of the cell cycle and also induced different percentages of apoptosis in presence (0.9% versus 4.4%) or absence (2.4% versus 28.5%) of serum (P = 0.0001). Zol concentration from 5 to 100 μm for 2 days induced significant concentration‐dependent cell death in adherent cells. Furthermore, Zol (10–100 μm ) induced dose‐dependent reduction both of mRNA and protein expression of VEGF associated with parallel decrease in VEGF secretion in the culture medium. Conclusion: Taken together, these results support a possible anti‐cancer and anti‐angiogenetic activity of Zol. Our data may not only provide a basis for the clinical use of this drug as preventive agent of bone metastases but also suggest that Zol deserves attention as an anti‐cancer agent in non‐small‐cell lung cancer.  相似文献   
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We describe the design, construction, and operating characteristics of a doubly resonant cylindrical microwave cavity. This cavity has been developed to allow a search for nonlinear RF energy conversion in biological cells. Cells with a diode-like nonlinearity could demodulate a modulated RF carrier wave and generate low frequency signals in an exposed biological preparation. The cavity is designed to be resonant on the TE(111) mode at about 890 MHz and on the TE(113) mode at about 1780 MHz. The cavity performs exactly as designed and has proved capable of detecting the nonlinearity in a microscopic Schottky diode test structure. The sensitivity is sufficient to detect any nonlinearity in a collection of biological cells that could have any potential biological significance.  相似文献   
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Background

The detection of regional wall motion abnormalities is the cornerstone of stress echocardiography. Today, stress echo shows increasing trends of utilization due to growing concerns for radiation risk, higher cost and stronger environmental impact of competing techniques. However, it has also limitations: underused ability to identify factors of clinical vulnerability outside coronary artery stenosis; operator-dependence; low positivity rate in contemporary populations; intermediate risk associated with a negative test; limited value of wall motion beyond coronary artery disease. Nevertheless, stress echo has potential to adapt to a changing environment and overcome its current limitations.

Integrated-quadruple stress-echo

Four parameters now converge conceptually, logistically, and methodologically in the Integrated Quadruple (IQ)-stress echo. They are: 1- regional wall motion abnormalities; 2-B-lines measured by lung ultrasound; 3-left ventricular contractile reserve assessed as the stress/rest ratio of force (systolic arterial pressure by cuff sphygmomanometer/end-systolic volume from 2D); 4- coronary flow velocity reserve on left anterior descending coronary artery (with color-Doppler guided pulsed wave Doppler). IQ-Stress echo allows a synoptic functional assessment of epicardial coronary artery stenosis (wall motion), lung water (B-lines), myocardial function (left ventricular contractile reserve) and coronary small vessels (coronary flow velocity reserve in mid or distal left anterior descending artery). In “ABCD” protocol, A stands for Asynergy (ischemic vs non-ischemic heart); B for B-lines (wet vs dry lung); C for Contractile reserve (weak vs strong heart); D for Doppler flowmetry (warm vs cold heart, since the hyperemic blood flow increases the local temperature of the myocardium). From the technical (acquisition/analysis) viewpoint and required training, B-lines are the kindergarten, left ventricular contractile reserve the primary (for acquisition) and secondary (for analysis) school, wall motion the university, and coronary flow velocity reserve the PhD program of stress echo.

Conclusion

Stress echo is changing. As an old landline telephone with only one function, yesterday stress echo used one sign (regional wall motion abnormalities) for one patient with coronary artery disease. As a versatile smart-phone with multiple applications, stress echo today uses many signs for different pathophysiological and clinical targets. Large scale effectiveness studies are now in progress in the Stress Echo2020 project with the omnivorous “ABCD” protocol.
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9.
Human cytochrome P450 3A4 forms a series of minor testosterone hydroxylation products in addition to 6 beta-hydroxytestosterone, the major product. One of these, formed at the next highest rate after the 6 beta- and 2 beta-hydroxy products, was identified as 1 beta-hydroxytestosterone. This product was characterized from a mixture of testosterone oxidation products using an HPLC-solid phase extraction-cryoprobe NMR/time-of-flight mass spectrometry system, with an estimated total of approximately 6 microg of this product. Mass spectrometry established the formula as C(19)H(29)O(3) (MH(+) 305.2080). The 1-position of the added hydroxyl group was established by correlated spectroscopy and heteronuclear spin quantum correlation experiments, and the beta-stereochemistry of the added hydroxyl group was assigned with a nuclear Overhauser correlated spectroscopy experiment (1 alpha-H). Of several human P450s examined, only P450 3A4 formed this product. The product was also formed in human liver microsomes.  相似文献   
10.
The aim of the present study was to investigate the effects of inhibition of the enzyme inducible nitric oxide synthase (iNOS) by aminoguanidine (AG) on the in vitro maturation of oocyte-cumulus cell complex(es) (COC) of cattle. COC were cultured with different concentrations of AG (0, 1, 10, and 100mM) for 24h. In Experiment 1, the extent of cumulus complex expansion, nuclear maturation status and plasma membrane integrity of oocytes and cumulus cells from each treatment were assessed. Nitrate/nitrite (NO(3)(-)/NO(2)(-)) concentrations were determined in culture medium by the Griess method. Addition of different concentrations of AG to maturation medium promoted a dose-response inhibitory effect on cumulus expansion (P<0.05). Addition of 1 and 10mM AG to IVM medium did not affect plasma membrane integrity of oocytes or nuclear maturation rates (P>0.05), but it did reduce plasma membrane integrity in cumulus cells. One hundred millimolar inhibited pre-metaphase I (pre-MI) to metaphase II (MII) transition, promoted plasma membrane damage in oocytes (P<0.05), and increased NO(3)(-)/NO(2)(-) concentration when compared to controls (P<0.05). To evaluate if this effect was reversible, 10(-5)M sodium nitroprusside (SNP, NO donor) was added, only in the treatment with 100mM AG that inhibited the nuclear maturation. However, association of 10(-5)M SNP to 100mM AG did not reverse the effects of AG, but increased NO(3)(-)/NO(2)(-)concentration (P<0.05). In Experiment 2, the effect of different AG concentrations on cytoplasmic maturation in vitro was assessed based on cortical granule migration, and embryonic development. There was a dose effect on cortical granule migration rate, in which 1mM AG (83.9+/-6.2%) did not differ from control oocytes (83.6+/-8.2%; P>0.05), but 10mM partially inhibited migration (3.8+/-6.4%) and 100mM totally inhibited migration (P<0.05). SNP (10(-5)M) did not revert this inhibitory effect on cortical granules migration in oocytes treated with 100mM AG. Only those concentrations that did not inhibit IVM were used to assess cleavage and blastocyst development. Addition of 10mM AG to IVM medium reduced (73.0+/-8.1%, 15.0+/-8.9%; P<0.05) cleavage and blastocyst development, respectively when compared with controls (89.1+/-3.4%, 37.6+/-7.3%, respectively), but did not differ, (P>0.05), from the group treated with 1mM AG (80.9+/-8.4%, 41.5+/-10.5%, respectively). The results from the present study demonstrate that NO derived from iNOS affects the in vitro maturation of bovine COC, modulating the viability of cumulus cells and of oocyte, the progression of meiosis after GVBD, the migration of cortical granules, and cleavage and blastocyst development.  相似文献   
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