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71.
João Batista A Oliveira Mario Cavagna Claudia G Petersen Ana L Mauri Fabiana C Massaro Liliane FI Silva Ricardo LR Baruffi Jose G Franco Jr 《Reproductive biology and endocrinology : RB&E》2011,9(1):1-7
Background
The role of serum anti-Müllerian hormone (AMH) as predictor of in-vitro fertilization outcomes has been much debated. The aim of the present study is to investigate the practicability of combining serum AMH level with biological age as a simple screening method for counseling IVF candidates of advanced reproductive age with potential poor outcomes prior to treatment initiation.Methods
A total of 1,538 reference patients and 116 infertile patients aged greater than or equal to 40 years enrolled in IVF/ICSI cycles were recruited in this retrospective analysis. A reference chart of the age-related distribution of serum AMH level for Asian population was first created. IVF/ICSI patients aged greater than or equal to 40 years were then divided into three groups according to the low, middle and high tertiles the serum AMH tertiles derived from the reference population of matching age. The cycle outcomes were analyzed and compared among each individual group.Results
For reference subjects aged greater than or equal to 40 years, the serum AMH of the low, middle and high tertiles were equal or lesser than 0.48, 0.49-1.22 and equal or greater than 1.23 ng/mL respectively. IVF/ICSI patients aged greater than or equal to 40 years with AMH levels in the low tertile had the highest cycle cancellation rate (47.6%) with zero clinical pregnancy. The nadir AMH level that has achieved live birth was 0.56 ng/mL, which was equivalent to the 36.4th percentile of AMH level from the age-matched reference group. The optimum cut-off levels of AMH for the prediction of nonpregnancy and cycle cancellation were 1.05 and 0.68 ng/mL, respectively.Conclusions
Two criteria: (1) age greater than or equal to 40 years and (2) serum AMH level in the lowest tertile (equal or lesser than 33.3rd percentile) of the matching age group, may be used as markers of futility for counseling IVF/ICSI candidates. 相似文献72.
Bezerra PG Britto MC Correia JB Duarte Mdo C Fonceca AM Rose K Hopkins MJ Cuevas LE McNamara PS 《PloS one》2011,6(4):e18928
Background
Acute respiratory infection (ARI) is a leading cause of morbidity and mortality in children worldwide. This study aimed to determine the viral and atypical bacterial causes of different severities and clinical manifestations of ARI in preschool children from low-income families in North-East Brazil.Methods
Clinical/demographic data and nasopharyngeal aspirates (NPA) were prospectively collected from children <5 years presenting with ARI over one year to a paediatric A&E department. Disease severity was grouped according to presence of lower respiratory tract signs, need for hospital admission and need for oxygen. Clinical manifestation of ARI was based on discharge diagnosis from hospital with four conditions predominating: bronchiolitis, pneumonia, episodic viral wheeze/asthma and upper respiratory tract infection. Multiplex PCR was used to detect 17 common respiratory viral and atypical bacterial pathogens in NPA.Findings
407 children with a median age of eight months were recruited. Pathogens were detected in 85·5% samples with co-infection being particularly common (39·5%). Respiratory Syncytial Virus (RSV; 37%), Adenoviruses (AdV; 25%), Rhinoviruses (hRV; 19%), Bocavirus (hBoV; 19%), human Meta-pneumovirus (hMPV; 10%) and Mycoplasma pneumoniae (Mpp; 10%) were most prevalent. Detection and co-infection rates were similar in all severities and clinical manifestations of ARI apart from RSV, which was associated with more severe disease and specifically more severe cases of bronchiolitis, and Mpp, which was associated with more severe cases of pneumonia. Mpp was detected in 17% of children admitted to hospital with pneumonia.Interpretation
This study underlines the importance of viral and atypical bacterial pathogens in ARI in pre-school children and highlights the complex epidemiology of these pathogens in this age group. Generally, viruses and atypical bacteria were detected in all severities and clinical manifestations of ARI but RSV and Mpp were associated with more severe cases of bronchiolitis and pneumonia respectively. 相似文献73.
Sodium as nutrient and toxicant 总被引:3,自引:0,他引:3
Herbert J. Kronzucker Devrim Coskun Lasse M. Schulze Jessie R. Wong Dev T. Britto 《Plant and Soil》2013,362(1-2):1-23
Background and Scope
Because of the crucial role coarse roots (>2 mm diameter) play in plant functions and terrestrial ecosystems, detecting and quantifying the size, architecture, and biomass of coarse roots are important. Traditional excavation methods are labor intensive and destructive, with limited quantification and repeatability of measurements over time. As a nondestructive geophysical tool for delineating buried features in shallow subsurface, ground penetrating radar (GPR) has been applied for coarse root detection since 1999. This article reviews the state-of-knowledge of coarse root detection and quantification using GPR, and discusses its potentials, constraints, possible solutions, and future outlooks. Some useful suggestions are provided that can guide future studies in this field.Conclusions
The feasibility and accuracy of coarse root investigation by GPR have been tested in various site conditions (mostly in controlled conditions or within plantations) and for different plant species (mostly tree root systems). Thus far, single coarse root identification and coarse root system mapping have been conducted using GPR, including roots under pavements in urban environment. Coarse root diameter and biomass have been estimated from indexes extracted from root GPR radargrams. Coarse root development can be observed by repeated GPR scanning over time. Successful GPR-based coarse root investigation is site specific, and only under suitable conditions can reliable measurements be accomplished. The best quality of root detection by GPR is achieved in well-drained and electrically-resistive soils (such as sands) under dry conditions. Numerous factors such as local soil conditions, root electromagnetic properties, and GPR antenna frequency can impact the reliability and accuracy of GPR detection and quantification of coarse roots. As GPR design, data processing software, field data collection protocols, and root parameters estimation methods are continuously improved, this noninvasive technique could offer greater potential to study coarse roots. 相似文献74.
Based on comprehensive distributional records of the 23 species currently assigned to the lizard genus Tropidurus, we investigated patterns of endemism and area relationships in South America. Two biogeographic methods were applied, Parsimony Analysis of Endemicity (PAE) and Brooks Parsimony Analysis (BPA). Two areas of endemism were detected by PAE: the first within the domains of the semiarid Brazilian Caatinga, which includes seven endemic species, and the second in the region of the Serranía de Huanchaca, eastern Bolivia, in which three endemic species are present. The area cladograms recovered a close relationship between the Atlantic Forest and areas of the South American open corridor. The results revealed a close relationship among the provinces Caatinga (Cerrado, Parana Forest (Pantanal+Chaco)). The uplift of the Brazilian Central Plateau in the Late Pliocene-Early Pleistocene (4-2 Myr BP) has been interpreted as a major event responsible for isolation and differentiation of biotas along these areas. However, we emphasize that without the establishment of a temporal framework concerning the diversification history of Tropidurus it is premature to correlate cladogenetic events with specific time periods or putative vicariant scenarios. The limiting factors hampering the understanding of the biogeographic history of this genus include (1) the absence of temporal references in relation to the diversification of distinct clades within Tropidurus; (2) the lack of an appropriate taxonomic resolution of the species complexes currently represented by widely distributed forms; and (3) the need for a comprehensive phylogenetic hypothesis. We suggest that these three important aspects should be prioritized in future investigations. 相似文献
75.
76.
Ennes-Vidal V Castro RO Britto C Barrabin H D'Avila-Levy CM Moreira OC 《Parasitology》2011,138(8):960-968
Recent have shown the relationship between Ecto-Nucleoside-Triphosphate-Diphosphohydrolases (Ecto-NTPDases or ecto-nucleotidases) and virulence and infectivity in trypanosomatids. In this work, the inhibition of the ecto-ATPase activities and promastigote growth of Leishmania amazonensis by CrATP was characterized. Furthermore, this compound was used to investigate the role of ecto-nucleotidase in the interaction of L. amazonensis with resident peritoneal macrophages obtained from BALB/c mice. CrATP partially inhibits the ecto-ATPase activity, presenting Ki values of 575·7±199·1 and 383·5±79·0 μm, in the presence or absence of 5 mm MgCl2, respectively. The apparent Kms for ATP (2·9±0·5 mm to Mg2+-dependent ecto-ATPase and 0·4±0·2 mm to Mg2+-independent ecto-ATPase activities) are not significantly altered by CrATP, suggesting a reversible non-competitive inhibition of both enzymes. When CrATP was added to the cultivation medium at 500 μm, it drastically inhibited the cellular growth. The interaction of promastigote forms of L. amazonensis with BALB/c peritoneal macrophages is strongly affected by CrATP. When the parasites were treated with 500 μm CrATP before interacting with macrophages, the adhesion and endocytic indices were strongly reduced to 53·0±14·8% and 39·8±1·1%, respectively. These results indicate that ecto-nucleotidase plays an important role in the infection process caused by Leishmania amazonensis. 相似文献
77.
78.
Dias Ricardo M. Lima Sergio M. Q. Mendes Liana F. Almeida Daniel F. Paiva Paulo C. Britto Marcelo R. 《Hydrobiologia》2019,829(1):133-142
Hydrobiologia - Cladocerans feed on a variety of phytoplankton food sources, which are variable across space and time. Different phytoplankton groups represent different nutritional quality to... 相似文献
79.
Tainah Silva Galdino Rubem Figueiredo Sadok Menna-Barreto Constança Britto Franklyn Samudio Adeilton Brandão Dário Eluan Kalume 《Analytical biochemistry》2014
We have developed a cell disruption method to produce a protein extract using Trypanosoma cruzi cells based on a straightforward hypoosmotic lysis protocol. The procedure consists of three steps: incubation of the cells in a hypoosmotic lysis buffer, sonication in a water bath, and centrifugation. The final protein extract was designated TcS12. The stages of cell disruption at different incubation times were monitored by differential interference contrast microscopy. After 30 min of incubation in lysis buffer at 4 °C, the T. cruzi epimastigote forms changed from slender to round-shaped parasites. Nevertheless, cell disruption took place following sonication of the sample for 30 min. The efficiency of the methodology was also validated by flow cytometry, which resulted in 72% of propidium iodide (PI)-labeled cells. To estimate the protein extraction yield and the differential protein expression, the proteomics profile of four T. cruzi strains (CL-Brener, Dm28c, Y, and 4167) were analyzed by liquid chromatography tandem mass spectrometry (LCMS/MS) on a SYNAPT HDMS system using the label-free MSE approach. ProteinLynx Global Server (version 2.5) with ExpressionE analysis identified a total of 1153 proteins and revealed 428 differentially expressed proteins among the strains. Gene ontology analysis showed that not only cytosolic proteins but also nuclear and organellar ones were present in the extract. 相似文献
80.
The relationships between foliage permanence and flowering throughout the year were analyzed in 92 woody species of Cerrado vegetation categorized as either deciduous (DE), semideciduous (SD) or evergreen (EV). Flowering of DE, SD and EV species was investigated via three variables, measured over the course of the year: flowering duration (FLD), calculated as the number of months in flower in each species; flowering distribution (FDI), calculated as the number of species in flower per month; and flowering peak (FPE), defined as the four consecutive months yielding the highest number of species in flower. The months with the highest numbers of species in flower were October (52 species), September (50) and August (49). These months correspond to the period of transition from the dry season to the wet season. In the majority of species studied, seasonal climatic factors were strong enough to induce fruit formation in the dry season and seed dispersal in the following wet season, when sufficient water was available to support germination and plantlet growth. However, significant differences in FLD, FDI and FPE were found among the leaf phenological groups. High FLD in EV species is likely favored by the continuous input of resources from the year-round foliage. In contrast, DE species employ reserves of carbon, water and nutrients to form new leaves and flowers on a crown free of foliage at the end of the dry season. In DE species, their low FLD may reduce the impact of flowering on reserve consumption. SD species showed an intermediate level of foliage persistence, resulting in intermediate FLD values. In addition, SD species exhibited a different pattern of flowering distribution from those of DE and EV species. Many SD species have two flowering periods per year. The first period occurs when the crowns are full of leaves, in the middle of the dry season in June, similar to EV species. The second occurs when only half of the original foliage area is present, near the peak of the dry season in September, similar to DE species. Therefore, despite a strong influence of seasonal climatic conditions on the flowering behavior of DE, SD and EV woody species of Cerrado vegetation, these leaf phenological groups differ significantly in FLD, FDI and FPE. 相似文献