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1.
Artigo em Inglês | MEDLINE | ID: mdl-32079120

RESUMO

The water-level fluctuation zone (WLFZ) is a transitional zone between terrestrial and aquatic ecosystems. Plant communities that are constructed artificially in the WLFZ can absorb and retain nutrients such as nitrogen (N) and phosphorus (P). However, the microbial community composition and function associated with this process have not been elucidated. In this study, four artificially constructed plant communities, including those of herbs (Cynodon dactylon and Chrysopogon zizanioides), trees (Metasequoia glyptostroboides), and shrubs (Salix matsudana) from the newly formed WLFZ of the Danjiangkou Reservoir were evaluated. The bacterial community compositions were analyzed by 16S rRNA gene sequencing using a MiSeq platform, and the functions of these communities were assessed via Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis. The results showed that the bacterial communities primarily comprised 362 genera from 24 phyla, such as Proteobacteria, Acidobacteria, Actinobacteria, and Gemmatimonadetes, showing the richness of the community composition. Planting altered the bacterial community composition, with varying effects observed among the different plant types. The bacterial community functional analysis revealed that these bacteria were primarily associated with six biological metabolic pathway categories (e.g., metabolism, genetic information processing, and environmental information processing) with 34 subfunctions, showing the richness of community functions. The planting of M. glyptostroboides, S. matsudana, and C. dactylon improved the metabolic capabilities of bacterial communities. N- and P-cycling gene analysis showed that planting altered the N- and P-cycling metabolic capacities of soil bacteria. The overall N- and P-metabolic capacity was highly similar between C. dactylon and C. zizanioides samples and between S. matsudana and M. glyptostroboides samples. The results of this study provide a preliminary analysis of soil bacterial community structure and function in the WLFZ of the Danjiangkou Reservoir and provides a reference for vegetation construction in this zone.

2.
Arch Microbiol ; 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32067064

RESUMO

Soil microbes play important roles in plant growth and in the biogeochemical cycling of earth's elements. However, the structure and functions of the microbial community associated with the growth of second-generation energy crops, such as Miscanthus, remain unclear. Thus, in this study, the composition and function of the bacterial and fungal communities associated with Miscanthus cultivation were analyzed by MiSeq sequencing combined with PICRUSt and FUNGUIld analyses. The results of community composition and diversity index analyses showed that Miscanthus cultivation significantly altered the bacterial and fungal community composition and reduced bacterial and fungal diversity. In addition, Miscanthus cultivation increased the soil organic matter (SOM) and total nitrogen (TN) contents. The correlation analysis between microbial community composition and environmental factors indicated that SOM and TN were the most important factors affecting bacterial and fungal communities. Miscanthus cultivation could enrich the abundances of Pseudomonas, Rhizobium, Luteibacter, Bradyrhizobium, Phenylobacterium and other common plant-promoting bacteria, while also increasing Cladophialophora, Hymenula, Magnaporthe, Mariannaea, etc., which predicted corresponded to the saprotrophic, plant pathogenic, and pathotrophic trophic modes. The PICRUSt predictive analysis indicated that Miscanthus cultivation altered the metabolic capabilities of bacterial communities, including the metabolism of carbon, nitrogen, and phosphorus cycle. In addition, FUNGUIld analysis indicated that Miscanthus cultivation altered the fungal trophic mode. The effects of Miscanthus on the communities and function of bacteria and fungi varied among Miscanthus species. Miscanthus specie Xiangdi NO 1 had the greatest impact on soil bacterial and fungal communities, whereas Miscanthus specie Wujiemang NO 1 had the greatest impact on soil bacteria and fungi functions. The results of this study provide a reference for the composition and function of microbial communities during the growth of Miscanthus.

3.
Arch Microbiol ; 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31894394

RESUMO

Network analysis has contributed to studies of the interactions of microorganisms and the identification of key populations. However, such analysis has rarely been conducted in the study of reservoir bacterioplankton communities. This study investigated the bacterioplankton community composition in the surface water of the Danjiangkou Reservoir using the Illumina MiSeq sequencing platform. We observed that the bacterioplankton community primarily consisted of 27 phyla and 336 genera, including Actinobacteria, Proteobacteria, and Bacteroidetes, demonstrating the richness of the community composition. Redundancy analysis of the bacterioplankton communities and environmental variables showed that the total nitrogen (TN), pH, chemical oxygen demand (COD), and permanganate index (CODMn) were important factors affecting the bacterioplankton distribution. Network analysis was performed using the relative abundances of bacterioplankton based on the phylogenetic molecular ecological network (pMEN) method. The connectivity of node i within modules (Zi), the connectivity of node i among modules (Pi), and the number of key bacteria were high at the Taizishan and Heijizui sites, which were associated with higher TN contents than at the other sites. Among the physicochemical properties of water, TN, ammonia nitrogen (NH4-N), pH, COD, and dissolved oxygen (DO) might have great influences on the functional units of the bacterial communities in bacterioplankton molecular networks. This study improves the understanding of the structure and function of bacterioplankton communities in the Danjiangkou Reservoir.

4.
Huan Jing Ke Xue ; 40(11): 5133-5141, 2019 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854583

RESUMO

To investigate the diversity of culturable bacteria and heavy metal-immobilizing bacteria in vegetable rhizosphere soil with high concentrations of heavy metals and explore these microbial resources, two samples of Italian lettuce rhizosphere soil with high heavy metal concentration (HY) and low heavy metal concentration (DK) were collected from Xinxiang, Henan Province. The diversity of culturable bacteria and heavy metal-immobilizing bacteria in the rhizosphere soil of lettuce was compared by culturable separation technology and a solution adsorption experiment. The enhancement of Cd and Pb immobilization and lettuce growth by the strains was also investigated in a hydroponic experiment. The results showed that 400 strains belonging to 3 phyla and 14 genera were isolated from the HY sample, with ß-Proteobacteria being the dominant phylum. Meanwhile, 400 strains belonging to 4 phyla and 30 genera were isolated from the DK sample, with Firmicutes being the dominant phylum. A total of 146 strains had a strong ability to immobilize heavy metal and the Cd and Pb removal rates were greater than 80% in the HY sample; Brevundimonas, Serratia, Arthrobacter, and Pseudarthrobacter were the main genera. However, 44 strains had a strong ability to immobilize heavy metal and the Cd and Pb removal rates were greater than 80% in the DK sample, with Bacillus being the main genus. Compared with the control, inoculation with Serratia liquefaciens HY-22, Bacillus thuringiensis HY-53, and Acinetobacter lwoffii HY-157 significantly increased the dry weight of roots (7.5%-77.6%) and shoots (15.4%-67.2%) of the Italian lettuce and cauliflower lettuce and reduced the contents of Cd (38.7%-66.6%) and Pb (34.7%-62.5%) in roots and shoots of Italian lettuce. In addition, the contents of Cd and Pb in the fresh shoots of Italian lettuce and cauliflower lettuce in the presence of Bacillus thuringiensis HY-53 were lower than the Cd and Pb limits set by national food safety standards. Thus, the results provided strain resources and a theoretical basis for the remediation of Cd-and Pb-contaminated farmlands for the safe production of crops.


Assuntos
Metais Pesados , Poluentes do Solo , Bactérias , Alface , Rizosfera , Solo
5.
Huan Jing Ke Xue ; 40(7): 3339-3346, 2019 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854736

RESUMO

The effects of heavy metal contamination on farmland continues to worsen progressively with an increase in anthropogenic activities such as industrial pollution and mining. Excess Cd and Pb in agricultural soils enter the food chain and adversely affect all organisms. Therefore, it is important to find an eco-friendly way to reduce heavy metal accumulation in crops. Based on their heavy metal resistance and growth-promoting characteristics, functional bacterial strains were screened and their effects on growth and heavy metal accumulation in wheat were verified via shaking flask adsorption and sand culture tests. Eighteen functional strains were isolated from the rhizospheric soil of Salvia setaria. Among them, Bacillus megaterium N3 and Serratia liquefaciens H12 were most effective at resisting high Cd (650 mg·L-1) and Pb (2700 mg·L-1) concentrations, and at producing indole-3-acetic acid (IAA) (56.6 mg·L-1and 69.1 mg·L-1, respectively), siderophores, and 1-Amino-1-cyclopropanecarboxylic acid (ACC) deaminase. Static incubation experiments showed that strains N3 and H12 significantly increased the NH4+ concentration and pH, and decreased the Cd (63.1%-73.8%) and Pb (69.1%-81.8%) concentration in solution. In sand cultures, strains N3 and H12 not only increased the dry weight of wheat roots (47.2%-97.4%) and shoots (65.3%-153%) significantly, but also significantly reduced the Cd (49.2%-68.3%) and Pb (27.4%-84.5%) content in wheat roots and shoots. Thus, the results provide strain resources and a theoretical basis for the remediation of Cd- and Pb-contaminated farmlands for the safer production of crops.


Assuntos
Bactérias/isolamento & purificação , Metais Pesados/análise , Microbiologia do Solo , Poluentes do Solo/análise , Triticum/química , Triticum/microbiologia
6.
Ying Yong Sheng Tai Xue Bao ; 30(6): 2030-2038, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31257776

RESUMO

Miscanthus is a promising candidate species of second-generation energy crops. To our knowledge, the composition and function of Miscanthus rhizosphere bacterial communities has not yet been reported. In this study, rhizosphere soil samples were collected from Miscanthus (Xiangzamang No. 1) which was grown in Nanyang City for five years and bareground (as the control) to analyze the bacterial community structure and diversity using 16S rRNA gene sequencing on the Illumina MiSeq platform. PICRUSt was used to determine the metabolic and functional abilities of soil bacterial communities. Phylogenetic analysis based on 16S rRNA gene sequences showed that sol bacteria could be divided into 23 phyla and 231 genera, with high richness of the community composition. The dominant phyla were Proteobacteria, Acidobacteria, Actinobacteria, Chloroflexi, Bacteroidetes and Gemmatimonadetes. The bacterial community diversity in the rhizosphere samples of Xiangzamang No. 1 was lower than that in unplanted samples. Rhizosphere bacterial communities were affected by Miscanthus crops. Based on the PICRUSt analysis of bacterial community functions, our results revealed a wide genetic diversity of organisms involved in various essential processes,such as amino acid transport and metabolism, cell wall/membrane/envelope biogenesis, signal transduction mechanisms. Based on the 16S rRNA gene copy number of the detected phylotypes, 22 bacterial metabolic function in the rhizosphere samples of Miscanthus was higher than that in bareground. Results from N- and P-cycling gene analysis showed that Miscanthus planting altered the N- and P-cycling metabolic capacities of soil bacteria.


Assuntos
Poaceae/crescimento & desenvolvimento , Microbiologia do Solo , Solo , Bactérias , Filogenia , RNA Ribossômico 16S
7.
Front Microbiol ; 10: 1455, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31316489

RESUMO

Previous analyses of plant growth-promoting bacteria (PGPB) combined with the remediation of heavy metal pollution in soil have largely been performed under potting or greenhouse conditions, and in situ remediation experiments under field conditions have rarely been reported. In this study, the effects of the metal-resistant PGPB Microbacterium oxydans JYC17, Pseudomonas thivervalensis Y1-3-9, and Burkholderia cepacia J62 on soil Cu pollution under rape remediation were studied in the farmland surrounding the Nanjing Jiuhuashan copper mining region in China. Following inoculation treatment for 50 days, the biomasses of the rape inoculated with strains JYC17, Y1-3-9, and J62 increased, and the total amounts of Cu uptake increased by 113.38, 66.26, and 67.91%, respectively, the translocation factor (TF) of rape inoculated with J62 was 0.85, a significant increase of 70.68%, thus improving the Cu remediation efficiency of the rape. Y1-3-9 and J62 affected the bioavailability of Cu in the soil, and the water-soluble Cu contents were increased by 10.13 and 41.77%, respectively, compared with the control. The antioxidant activities in the rape leaves showed that the tested bacteria increased the contents of antioxidant non-enzymatic substances, including ascorbic acid (ASA) and glutathione (GSH), which were increased by 40.24-91.22% and 9.89-17.67%, respectively, thereby reducing the oxidative stress caused by heavy metals and the contents of thiobarbituric acid-reactive substances (TBARS) and peroxidase (POD). PCR-denaturing gradient gel electrophoresis (PCR-DGGE) was used to analyze the effects of the tested bacteria on the cultivation-dependent and cultivation-independent bacterial communities in the root endosphere and rhizosphere soil of the rape. The sequencing results of the DGGE bands indicated that the tested bacteria colonized the endosphere and rhizosphere, and they became an important component of the cultivation-dependent bacteria. The canonical correspondence analysis (CCA) of the DGGE profile and similarity cluster analysis showed that the tested bacteria affected the cultivation-dependent and cultivation-independent bacterial communities in the root endosphere and rhizosphere. In this experiment, the effects and mechanisms of the combined plant-microbe remediation under field conditions were preliminarily studied, and the results are expected to provide a theoretical basis for future combined remediation experiments.

8.
Huan Jing Ke Xue ; 40(3): 1252-1260, 2019 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087972

RESUMO

Bacterioplankton are important components of aquatic ecosystems, and play a crucial role in the global biogeochemical cycle of nitrogen. In this study, surface-water samples were collected from Kuxin (the center of Danjiangkou Reservoir) and Qushou (the Middle Route of the South-to-North Water Diversion Project's canal head) in the Danjiangkou Reservoir in May 2016. Total DNA was isolated, and high-throughput sequencing was performed to analyze the community structure and diversity of bacteria. Phylogenetic analyses of 16S rDNA sequences showed that bacterial communities included species from 12 major phylogenetic groups. The predominant phylogenetic groups included Proteobacteria, Bacteroidetes, Firmicutes, Cyanobacteria, and Verrucomicrobia. The microbial biodiversity of Danjiangkou Reservoir bacterioplankton was greater in water samples from Qushou than in those from Kuxin. PICRUSt (phylogenetic investigation of communities by reconstruction of unobserved states) was used to determine the metabolic and functional abilities of the observed bacterial communities. Our results revealed a wide genetic diversity of organisms involved in various essential processes, such as Amino acid transport and metabolism, Transcription, Energy production and conversion, and Carbohydrate transport and metabolism. Thirty-five metabolic pathways involving nitrogen were detected. Key genes impacting the nitrogen cycle were detected in both the Kuxin and Qushou samples, and these encoded enzymes involved in nitrogen fixation (nifH), nitrification (hao), denitrification (narG、nirK、norB、nosZ), and assimilatory and dissimilatory nitrogen reduction to ammonia (nasA、narB、napA、nirA、nirB、nrfA). Copy numbers of 16S rRNA genes of each detected phylotype of Danjiangkou Reservoir bacterioplankton were uniformly higher in water samples from Kuxin than in water samples from Qushou. Our analyses of differences in nitrogen abatement potential between water samples, based on bacterial community composition and function, provide a foundation for setting water environmental protection policies in the Danjiangkou Reservoir.

9.
Huan Jing Ke Xue ; 40(1): 421-429, 2019 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-30628301

RESUMO

Microbial communities play crucial roles in the global biogeochemical nitrogen cycle. To our knowledge, the compositions and functions of rhizosphere communities in riparian buffer strips have not been reported. In this study, rhizosphere soil samples were collected from herbs (Vetiveria zizanioides and Phragmites australis), trees (Pyrus betulifolia), and shrubs (Discocleidion rufescens) in the Danjiangkou Reservoir in June 2017. High-throughput sequencing was performed to analyze the community structure and diversity of bacteria. Phylogenetic analysis based on 16S rDNA sequences shows that the bacterial communities can be divided into 31 major phylogenetic groups. The dominant phylogenetic groups include Proteobacteria, Bacteroidetes, Actinobacteria, Gemmatimonadetes, and Acidobacteria. Phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) was used to determine the metabolic and functional abilities of the observed bacterial communities. Our results reveal a wide genetic diversity of organisms involved in various essential processes such as biosynthesis of other secondary metabolites, transcription, Glycan biosynthesis and metabolism, cell growth and death, and carbohydrate metabolism. Based on the 16S rRNA gene copy number of the detected phylotype, the bacterial rhizospheres of plants in riparian buffer strips can be ranked as follows:Discocleidion rufescens > Phragmites australis > Vetiveria zizanioides > Pyrus betulifolia. We analyzed the differences of different plants from the perspective of bacterial community composition and function and provide a foundation for vegetation construction and water environmental protection in riparian buffer strips of the Danjiangkou Reservoir.


Assuntos
Bactérias/classificação , Rizosfera , Microbiologia do Solo , China , Ecossistema , Filogenia , RNA Ribossômico 16S/genética
10.
Huan Jing Ke Xue ; 39(8): 3591-3600, 2018 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-29998665

RESUMO

Reservoir/lake sediments are potential pollutant acceptors and sources of pollution. The Danjiangkou Reservoir, as the largest drinking water source in China, is the source water area for the Mid-route Project of the South-North Water Diversion. To illustrate the temporal and spatial changes in the environmental risks of both nutrients and heavy metals in the surface sediments of Danjiangkou Reservoir, the levels of pH, OM, TP, TN, and six kinds of metal elements during the period 2011-2016 were measured at five ecological sites. Canadian freshwater sediment quality guidelines for aquatic environments (from the CCME) were used to assess the potential ecological risks. The results showed that the contents of OM, TP, and TN in the surface sediments were 25.85, 0.57, and 1.34 g·kg-1, respectively, and those of Cr, Mn, Cu, Zn, Cd, and Pb were 57.96, 521.78, 13.91, 195.74, 0.37, and 12.92 mg·kg-1, respectively. The contents of both Zn and Cd were under the corresponding Ⅱ-level standards of soil environmental quality, but the contents of the other four heavy metals were lower than their corresponding I-level standards. After water diversion of the Mid-route Project, the OM, TN, Mn, and Zn contents increased, and the TP and other heavy metal contents displayed downward trends. Excluding the pH value, the distribution of measured nutrients and heavy metals in the surface sediments of the Danjiangkou Reservoir reached the extremely significant level (P<0.01). OM in the sediments was negatively correlated with TN and Pb, but had positive correlations with the other indicators measured. The results from the potential ecological risk assessment showed that:①Cd, Cu, and Pb had no harmful effects on organisms; ② OM had low ecological risk in most years; ③ the risk of TP was between zero and low ecological risk; and ④Cr, Zn, and TN had low ecological risk in most cases. The K and H sites had higher ecological risk for Cr, Zn, and TN, thus attention should be paid to those cases. These results illustrate the effects of human activities on nutrients and heavy metals in surface sediments.

11.
Ann Acad Med Singapore ; 45(8): 357-63, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27683740

RESUMO

INTRODUCTION: Hashimoto's thyroiditis (HT) can present as focal nodular disease. This study aimed to determine the distinguishing sonographic features of nodules in biopsy-proven focal HT. MATERIALS AND METHODS: The study included 388 thyroid nodules from 310 patients who underwent ultrasound-guided fine-needle aspiration biopsy (FNAB). There were 28 focal HT, 27 malignant and 333 other benign nodules. Sonographic features of focal HT nodules on prebiopsy ultrasound were compared with malignant nodules and other benign nodules using multinomial logistic regression adjusting for the correlation between multiple nodules obtained from the same patient. RESULTS: Most focal HT nodules were purely solid (92.8%), iso-hyperechoic (70.4%), had regular margins (75.0%) and central vascularity (85.7%). Hypoechogenicity (29.6% vs 42.3%; P = 0.017) and microcalcifications (3.6% vs 44.4%; P = 0.003) were significantly less common in focal HT than malignant nodules. None of the focal HT nodules demonstrated marked hypoechogenicity, irregular margins or cervical lymphadenopathy, which are traditionally associated with malignancy. Compared to other benign nodules, focal HT nodules were significantly more likely to be purely solid (92.8% vs 49.0%; P = 0.016), ill-defined (25.0% vs 7.0%; P = 0.004) and lack comet-tail artefacts (92.9% vs 66.1%; P = 0.012), which in combination were 17.9% sensitive and 94.6% specific for focal HT. CONCLUSION: Awareness of the above-described sonographic appearances of focal HT may aid in differentiating them from malignant nodules and risk-stratify for FNAB. While there is substantial overlap with other benign nodules, a combination of the above-mentioned 3 ultrasound features is highly specific for focal HT and can prompt further serological evaluation in clinically unsuspected HT.


Assuntos
Doença de Hashimoto/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/diagnóstico por imagem , Biópsia por Agulha Fina , Calcinose/diagnóstico por imagem , Estudos de Casos e Controles , Doença de Hashimoto/complicações , Doença de Hashimoto/patologia , Humanos , Biópsia Guiada por Imagem , Modelos Logísticos , Linfonodos/diagnóstico por imagem , Linfadenopatia/complicações , Linfadenopatia/diagnóstico por imagem , Pescoço , Neoplasias da Glândula Tireoide/complicações , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/complicações , Nódulo da Glândula Tireoide/patologia , Ultrassonografia
12.
Yi Chuan ; 38(5): 436-43, 2016 05.
Artigo em Chinês | MEDLINE | ID: mdl-27232492

RESUMO

Plants not only use light as an energy source for photosynthesis, but also have to monitor the light quality and quantity input to execute appropriate physiological and developmental responses, such as cell differentiation, structural and functional changes, as well as the formation of tissues and organs. The process is referred to as photomorphogenesis. Arabidopsis QUA1 (QUASIMODO1), which functions in pectin synthesis, is identified as a member of glycosyltransferases. Previously, the hypocotyl elongation of the qua1-1 mutant was shown to be inhibited under dark conditions. In this study, we used the qua1-1/cry1 and qua1-1/phyB double mutants as the materials to study the function of the QUA1 gene in light signal transduction. The results showed that QUA1 not only participated in hypocotyl elongation under dark conditions, but also in blue light, red light and far red light conditions. In qua1-1 mutant seedlings, both the cell length of hypocotyl and the light-regulated gene expression were affected. Compared with cry1 and phyB mutants, qua1-1/cry1 and qua1-1/phyB double mutants had the shorter hypocotyl. Light-regulated gene expression was also affected in the double mutants. These data indicated that QUA1 might participate in the light signal transduction regulated by CRY1 and PHYB. Hence, the QUA1 gene may play multiple roles in light signal transduction by regulating the cell elongation and light-regulated gene expression.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Hexosiltransferases/genética , Transdução de Sinal Luminoso/fisiologia , Proteínas de Arabidopsis/fisiologia , Criptocromos/genética , Regulação da Expressão Gênica de Plantas , Hexosiltransferases/fisiologia , Mutação , Fitocromo B/genética
13.
Eur J Obstet Gynecol Reprod Biol ; 192: 41-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26149478

RESUMO

OBJECTIVE(S): To explore the use of competing risk (CR) as compared to the commonly used Kaplan-Meier (KM) methodology in estimating the cumulative live-birth rate (CLBR) after IVF Treatment in a context of high dropout rates and informative censoring. STUDY DESIGN: We compare the KM and CR methodologies for estimating 2-year CLBR in a retrospective cohort of 2779 patients undergoing 5002 embryo transfers over a period of 9 years, from 2000 to 2008, at KKIVF Centre. RESULTS: We observed a total of 1105 LB (39.8%), and a dropout rate of 44.2% (1228 patients). The overall CLBR is lower with CR compared with KM method (39% vs 52%) after up to nine embryo-transfer cycles over a period of two years. The highest CLBR was achieved for ovulation disorders (57% vs 49%, KM vs CR) followed by male factors (54% vs 43%, KM vs CR), with poorer outcomes from patients with decreased ovarian reserve (37% vs 16%, KM vs CR) and endometriosis (36% vs 25%, KM vs CR). As dropouts in our cohort are generally older and more likely to have poorer ovarian reserves, the CR method, which accounted for these dropouts, is likely to give more meaningful estimation of IVF success rates. CONCLUSION(S): The CR method should be considered as a useful alternative in deriving CLBR for IVF treatment where dropout rates are high and when informative censoring is involved.


Assuntos
Fertilização In Vitro/estatística & dados numéricos , Estimativa de Kaplan-Meier , Nascimento Vivo , Pacientes Desistentes do Tratamento/estatística & dados numéricos , Adulto , Transferência Embrionária/estatística & dados numéricos , Feminino , Humanos , Infertilidade Feminina/terapia , Infertilidade Masculina/terapia , Masculino , Estudos Retrospectivos , Medição de Risco/métodos
14.
J Hazard Mater ; 244-245: 709-17, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23177252

RESUMO

Two metal-resistant and plant growth-promoting bacteria (Burkholderia sp. J62 and Pseudomonas thivervalensis Y-1-3-9) were evaluated for their impacts on plant growth promotion, Cd availability in soil, and Cd uptake in rape (Brassica napus) grown in different level (0, 50, and 100 mg kg(-1)) of Cd-contaminated soils. The impacts of the bacteria on the rape-associated bacterial community structures were also evaluated using denaturing gradient gel electrophoresis (DGGE) analysis of bacterial DNA extracted from the root interior and rhizosphere and bulk soil samples collected at day 60 after inoculation. Canonical correspondence analysis (CCA) was used to have a comparative analysis of DGGE profiles. Inoculation with live bacteria not only significantly increased root (ranging from 38% to 86%), stem (ranging from 27% to 65%) and leaf (ranging from 23% to 55%) dry weights and water-extractive Cd contents (ranging from 59% to 237%) in the rhizosphere soils of the rape but also significantly increased root (ranging from 10% to 61%), stem (ranging from 41% to 57%) and leaf (ranging from 46% to 68%) total Cd uptake of rape compared to the dead bacterial-inoculated controls. DGGE and sequence analyses showed that the bacteria could colonize the rhizosphere soils and root interiors of rape plants. DGGE-CCA also showed that root interior and rhizosphere and bulk soil community profiles from the live bacteria-inoculated rape were significantly different from those from the dead bacteria-inoculated rape respectively. These results suggested that the bacteria had the potential to promote the growth and Cd uptake of rape and to influence the development of the rape-associated bacterial community structures.


Assuntos
Brassica napus/microbiologia , Burkholderia/fisiologia , Cádmio/metabolismo , Pseudomonas/fisiologia , Poluentes do Solo/metabolismo , Brassica napus/crescimento & desenvolvimento , Brassica napus/metabolismo , DNA Bacteriano/análise , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Caules de Planta/crescimento & desenvolvimento , Caules de Planta/metabolismo , Microbiologia do Solo
15.
Chemosphere ; 83(1): 57-62, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21315404

RESUMO

One hundred Cu-resistant-endophytic bacteria were isolated from Cu-tolerant plants grown on Cu mine wasteland, of which, eight Cu-resistant and 1-aminocyclopropane-1-carboxylate (ACC) deaminase-producing endophytic bacteria were obtained based on the ACC deaminase activity of the bacteria and characterized with respect to metal resistance, production of ACC deaminase, indole-3-acetic acid (IAA) as well as siderophores and mineral phosphate solubilization. Ralstonia sp. J1-22-2, Pantoea agglomerans Jp3-3, and Pseudomonas thivervalensis Y1-3-9 with higher ACC deaminase activity (ranging from 213 to 370 µM α-ketobutyrate mg(-1)h(-1)) were evaluated for promoting plant growth and Cu uptake of rape grown in quartz sand containing 0, 2.5, and 5 mg kg(-1) of Cu in pot experiments. The eight bacteria were found to exhibit different multiple heavy metal resistance characteristics, to show different levels of ACC deaminase activity and to produce indole acetic acid. Seven bacteria produced siderophores and solubilized inorganic phosphate. Pot experiments showed that inoculation with the strains (J1-22-2, Jp3-3, and Y1-3-9) was found to increase the biomass of rape. Increases in above-ground tissue Cu contents of rape cultivated in 2.5 and 5 mg kg(-1) of Cu-contaminated substrates varied from 9% to 31% and from 3 to 4-fold respectively in inoculated-rape plants compared to the uninoculated control. The maximum Cu uptake of rape was observed after inoculation with P. agglomerans Jp3-3. The results show that metal-resistant and plant growth promoting endophytic bacteria play an important role in plant growth and Cu uptake which may provide a new endophytic bacterial-assisted phytoremediation of Cu-contaminated environment.


Assuntos
Bactérias/enzimologia , Brassica napus/microbiologia , Carbono-Carbono Liases/metabolismo , Cobre/toxicidade , Poluentes do Solo/toxicidade , Adaptação Fisiológica , Bactérias/classificação , Bactérias/genética , Sequência de Bases , Brassica napus/crescimento & desenvolvimento , Brassica napus/metabolismo , Cobre/metabolismo , Ácidos Indolacéticos/metabolismo , Dados de Sequência Molecular , Poluentes do Solo/metabolismo
16.
J Hazard Mater ; 186(2-3): 1720-5, 2011 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21227577

RESUMO

Forty-nine lead (Pb)-resistant endophytic bacteria were isolated from metal-tolerant Commelina communis plants grown on lead and zinc mine tailing, of which, seven 1-aminocyclopropane-1-carboxylate (ACC) deaminase-producing endophytic bacteria were initially obtained and characterized with respect to heavy metal resistance and production of ACC deaminase, indole-3-acetic acid (IAA) as well as siderophores. Two isolates (Q2BJ2 and Q2BG1) showing higher ACC deaminase activity were evaluated for promoting plant growth and Pb uptake of rape grown in quartz sand containing 0 and 100 mg kg(-1) of Pb in pot experiments. The seven Pb-resistant and ACC deaminase-producing endophytic bacterial isolates were found to exhibit different multiple heavy metal resistance characteristics and to show different levels of ACC deaminase activity (ranging from 12.8 µM α-KB mg(-1) h(-1) to 121 µM α-KB mg(-1) h(-1)). Among the seven isolates, six isolates produced indole acetic acid, whilst five isolates produced siderophores. In experiments involving rape plants grown in quartz sand containing 100 mg kg(-1) of Pb, inoculation with the isolates resulted in the increased dry weights of above-ground tissues (ranging from 39% to 71%) and roots (ranging from 35% to 123%) compared to the uninoculated control. Increases in above-ground tissue Pb contents of rape cultivated in 100 mg kg(-1) of Pb-contaminated substrates varied from 58% to 62% in inoculated-rape plants compared to the uninoculated control.


Assuntos
Bactérias/metabolismo , Brassica rapa/metabolismo , Carbono-Carbono Liases/antagonistas & inibidores , Carbono-Carbono Liases/farmacologia , Chumbo/metabolismo , Chumbo/farmacologia , Bactérias/crescimento & desenvolvimento , Brassica rapa/crescimento & desenvolvimento , Carbono-Carbono Liases/química , Poluentes Ambientais/análise , Resíduos Industriais/análise , Metais Pesados/farmacologia , Mineração , Sideróforos/metabolismo , Zinco/análise
17.
Qual Life Res ; 19(9): 1343-8, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20617386

RESUMO

PURPOSE: Hepatitis B virus (HBV) is endemic in Bangladesh, and the quality of life (QoL) of these patients remains unknown as there is no instrument available in the native language. In this study, we translated the 56-item Hepatitis Quality of Life Questionnaire (HQLQ) into Bengali and evaluated its validity and reliability. METHODS: Fifty patients with asymptomatic chronic hepatitis B and 50 similarly infected patients who received Lamivudine were recruited. The HQLQ instrument was administered to the participants at baseline and 6 months to evaluate its validity and reliability, as well as the responsiveness of the QoL scales. RESULTS: HBV patients reported lower scores on General Health, Vitality, Role Emotional, Physical Component Summary and Mental Component Summary, as compared with other scales. Item-scale correlations were generally large, thus supporting item convergent validity. Inter-scale correlations suggested convergent and discriminant validity. The instrument discriminated well between groups with differing clinical status and was responsive to changes in health status over time. CONCLUSIONS: Generally, we found the Bengali HQLQ to be a valid and reliable instrument for capturing the QoL and disease burden of HBV patients in Bangladesh.


Assuntos
Nível de Saúde , Hepatite/fisiopatologia , Qualidade de Vida , Inquéritos e Questionários , Adulto , Bangladesh , Feminino , Humanos , Masculino
18.
Bioresour Technol ; 101(2): 501-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19762232

RESUMO

The diversity of endophytic bacteria from the copper-tolerant species Elsholtzia splendens and Commelina communis was evaluated by using cultivation and cultivation-independent techniques. Phylogenetic analysis based on 16S rDNA sequences showed that the Cu-resistant isolates belonged to three major phylogenetic groups: Firmicutes, Actinobacteria and Proteobacteria. Bacillus and Acinetobacter were predominant among the Cu-resistant isolates. Sequence analysis from the 16S rDNA clone libraries of the two plant roots revealed sequences of Alpha-, Beta-, Gamma-Proteobacteria, Firmicutes,Actinobacteria and Bacteroidetes. Gammaproteobacteria was predominant in the two 16S rDNA clone libraries. Thirty-two endophytic bacteria were isolated and characterized with respect to heavy metal resistance and production of plant growth-promoting factors. In experiments involving rape plants grown in vermiculite containing 4 mg kg(-1) of Cu, inoculation with the isolates was found to increase the dry weights of roots (ranging from 132% to 155%) and above-ground tissues (ranging from 71% to 83%) compared to the uninoculated control. Increase in above-ground tissue Cu content varied from 63% to 125% in inoculated-rape plants cultivated in Cu-contaminated substrate compared to the uninoculated control.


Assuntos
Adaptação Fisiológica , Bactérias/efeitos dos fármacos , Biodiversidade , Cobre/farmacologia , Metais Pesados/toxicidade , Mineração , Plantas/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Sequência de Bases , Primers do DNA , DNA Ribossômico/genética , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética
19.
Ecotoxicol Environ Saf ; 72(5): 1343-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19368973

RESUMO

Two cadmium (Cd)-resistant strains Pseudomonas sp. RJ10 and Bacillus sp. RJ16 were investigated for their effects on the soil Cd and lead (Pb) solubilization and promotion of plant growth and Cd and Pb uptakes of a Cd-hyperaccumulator tomato. In the heavy metal-contaminated inoculated soil, the CaCl(2)-extractable Cd and Pb were increased by 58-104% and 67-93%, respectively, compared to the uninoculation control. The bacteria produced indole acetic acid, siderophore and 1-aminocyclopropane-1-carboxylate deaminase. Root elongation assay conducted on tomato under gnotobiotic conditions demonstrated increase in root elongation of inoculated tomato seedlings compared to the control plants. An increase in Cd and Pb contents of above-ground tissues varied from 92% to 113% and from 73% to 79% in inoculated plants growing in heavy metal-contaminated soil compared to the uninoculation control, respectively. These results show that the bacteria could be exploited for bacteria enhanced-phytoextraction of Cd- and Pb-polluted soils.


Assuntos
Bacillus/metabolismo , Cádmio/metabolismo , Chumbo/metabolismo , Lycopersicon esculentum/metabolismo , Pseudomonas/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Solo/análise , Bacillus/crescimento & desenvolvimento , Biodegradação Ambiental , Biomassa , Cádmio/toxicidade , Carbono-Carbono Liases/metabolismo , Farmacorresistência Bacteriana , Ácidos Indolacéticos/metabolismo , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/crescimento & desenvolvimento , Componentes Aéreos da Planta , Raízes de Plantas/metabolismo , Pseudomonas/crescimento & desenvolvimento , Plântula/metabolismo , Sideróforos/metabolismo , Poluentes do Solo/toxicidade
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