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1.
World J Microbiol Biotechnol ; 36(2): 29, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32016527

RESUMO

Short-chain halogenated aliphatic hydrocarbons (e.g. perchloroethene, trichloroethene) are among the most toxic environmental pollutants. Perchloroethene and trichloroethene can be dechlorinated to non-toxic ethene through reductive dechlorination by Dehalococcoides sp. Bioaugmentation, applying cultures containing organohalide-respiring microorganisms, is a possible technique to remediate sites contaminated with chlorinated ethenes. Application of site specific inocula is an efficient alternative solution. Our aim was to develop site specific dechlorinating microbial inocula by enriching microbial consortia from groundwater contaminated with trichloroethene using microcosm experiments containing clay mineral as solid phase. Our main goal was to develop fast and reliable method to produce large amount (100 L) of bioactive agent with anaerobic fermentation technology. Polyphasic approach has been applied to monitor the effectiveness of dechlorination during the transfer process from bench-scale (500 mL) to industrial-scale (100 L). Gas chromatography measurement and T-RFLP (Terminal Restriction Fragment Length Polymorphism) revealed that the serial subculture of the enrichments shortened the time-course of the complete dechlorination of trichloroethene to ethene and altered the composition of bacterial communities. Complete dechlorination was observed in enrichments with significant abundance of Dehalococcoides sp. cultivated at 8 °C. Consortia incubated in fermenters at 18 °C accelerated the conversion of TCE to ethene by 7-14 days. Members of the enrichments belong to the phyla Bacteroidetes, Chloroflexi, Proteobacteria and Firmicutes. According to the operational taxonomic units, main differences between the composition of the enrichment incubated at 8 °C and 18 °C occurred with relative abundance of acetogenic and fermentative species. In addition to the temperature, the site-specific origin of the microbial communities and the solid phase applied during the fermentation technique contributed to the development of a unique microbial composition.


Assuntos
Anaerobiose/fisiologia , Bactérias/metabolismo , Biodegradação Ambiental , Argila/química , Microbiota/fisiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Bacteroidetes/genética , Bacteroidetes/metabolismo , Chloroflexi/genética , Chloroflexi/metabolismo , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Fermentação , Firmicutes/genética , Firmicutes/metabolismo , Geobacter/genética , Geobacter/metabolismo , Água Subterrânea/microbiologia , Consórcios Microbianos , Polimorfismo de Fragmento de Restrição , Proteobactérias/genética , Proteobactérias/metabolismo , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificação , Tricloroetileno/química , Microbiologia da Água , Poluentes Químicos da Água/metabolismo
2.
Phys Rev Lett ; 124(4): 048101, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32058757

RESUMO

Microbial cells generally leak various metabolites including those necessary to grow. Why cells secrete even essential chemicals so often is, however, still unclear. Based on analytical and numerical calculations, we show that if the intracellular metabolism includes multibody (e.g., catalytic) reactions, leakage of essential metabolites can promote the leaking cell's growth. This advantage is typical for most metabolic networks via "flux control" and "growth-dilution" mechanisms, as a general consequence of the balance between synthesis and growth-induced dilution with autocatalytic reactions. We further argue that this advantage may lead to a novel form of symbiosis among diverse cells.


Assuntos
Microbiota/fisiologia , Modelos Biológicos , Biomassa , Redes e Vias Metabólicas
3.
Nature ; 579(7797): 123-129, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32103176

RESUMO

A mosaic of cross-phylum chemical interactions occurs between all metazoans and their microbiomes. A number of molecular families that are known to be produced by the microbiome have a marked effect on the balance between health and disease1-9. Considering the diversity of the human microbiome (which numbers over 40,000 operational taxonomic units10), the effect of the microbiome on the chemistry of an entire animal remains underexplored. Here we use mass spectrometry informatics and data visualization approaches11-13 to provide an assessment of the effects of the microbiome on the chemistry of an entire mammal by comparing metabolomics data from germ-free and specific-pathogen-free mice. We found that the microbiota affects the chemistry of all organs. This included the amino acid conjugations of host bile acids that were used to produce phenylalanocholic acid, tyrosocholic acid and leucocholic acid, which have not previously been characterized despite extensive research on bile-acid chemistry14. These bile-acid conjugates were also found in humans, and were enriched in patients with inflammatory bowel disease or cystic fibrosis. These compounds agonized the farnesoid X receptor in vitro, and mice gavaged with the compounds showed reduced expression of bile-acid synthesis genes in vivo. Further studies are required to confirm whether these compounds have a physiological role in the host, and whether they contribute to gut diseases that are associated with microbiome dysbiosis.


Assuntos
Ácidos e Sais Biliares/biossíntese , Ácidos e Sais Biliares/química , Metabolômica , Microbiota/fisiologia , Animais , Ácidos e Sais Biliares/metabolismo , Ácido Cólico/biossíntese , Ácido Cólico/química , Ácido Cólico/metabolismo , Fibrose Cística/genética , Fibrose Cística/metabolismo , Fibrose Cística/microbiologia , Vida Livre de Germes , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/microbiologia , Camundongos , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo
5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(1): 60-66, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31950791

RESUMO

Objective: To optimize the preparation parameters of the new silk birth-canal microecology transporter (BMT) for transferring the symbiotic bacteria of the birth canal efficiently. Methods: Birth canal microbial samples of 30 full term pregnant women at admission were collected as the control group (NC, n=30). The experimental group included 18 pregnant women terminated by Cesarean section, who were divided into 6 sub-groups (M1-M6, n=3) to complete the transfer tests of the birth-canal microecology. The new silk BMT was processed in the sterile liquid of the different osmotic pressure with the different immersion depth, and was placed in the vagina of the pregnant women for 1 h before sealed. All extracted DNA specimens were amplified in the V3-V4 region of the 16S rDNA, and were sequenced by Illumina Hiseq2500. Microbial diversity analysis was performed by Mothur, QIIME, Lefse and Metastat. Welch's t-test and Anosim nonparametric test were used to compare the difference between groups. Results: The new silk BMT with 70% immersion depth could be fully covered by the solution, and had good solution preserving and adhesion. The subjects had no foreign body sensation with satisfied experience. Both of the microbes on the new BMT and the control group were lactobacillus as the dominant bacteria genus. The microbial diversity and bacteria constitution in the new BMT was similar to the control group in the condition of 0.45% NaCl solution and 70% immersion depth, and there was no significant difference between the two groups ( P>0.05). Conclusion: The new silk BMT can transfer the symbiotic microbes of the birth canal efficiently, and the optimal preparation parameters were 0.45% hypotonic saline solution and 70% immersion depth.


Assuntos
Técnicas Microbiológicas , Microbiota , Seda , Vagina , Bactérias/classificação , Biodiversidade , Cesárea , Feminino , Humanos , Lactobacillus/fisiologia , Técnicas Microbiológicas/métodos , Microbiota/fisiologia , Gravidez , Vagina/microbiologia
7.
J Basic Microbiol ; 60(1): 4-13, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31682282

RESUMO

Salinity and drought are the major abiotic stresses that limit agricultural productivity. Application of plant growth promoting rhizobacteria (PGPR) is an attractive technology but with the bottlenecks of reduced efficacy and survivability in the environment. For increased efficiency of PGPR strains, the impact of stresses on the native bacterial community needs to be studied. Experimentally induced stresses would be ideal to assess the immediate perturbances in the structure of soil bacterial community. Hence, the study focused on the effect of experimentally-induced salinity, and drought stress on rhizospheric bacterial community of Cajanus cajan. A plant growth experiment was set up to induce salinity and drought stresses. Shifts in the bacterial community were assessed by a culture-independent technique of denaturing gradient gel electrophoresis using 16S ribosomal RNA gene and transcript as markers, leading to a comparison of the resident with the active bacterial community. The impact on plant was evaluated by measurement of plant biometrics. Further, salinity and drought-stressed conditions led to distinct shifts in native and active rhizospheric bacterial community, corresponding to the higher decline at induction of stresses, and stabilization at later time points. The study encompasses the perturbations in the active and resident rhizospheric bacterial community caused by the induction of two different abiotic stresses along the plant's growth.


Assuntos
Cajanus/microbiologia , Microbiota/fisiologia , Rizosfera , Estresse Fisiológico , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Cajanus/crescimento & desenvolvimento , Análise por Conglomerados , Secas , Microbiota/genética , RNA Ribossômico 16S/genética , Salinidade , Solo/química , Microbiologia do Solo
8.
Syst Appl Microbiol ; 43(1): 126024, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31708159

RESUMO

Conventional anaerobic digesters intended for the production of biogas usually operate in complete darkness. Therefore, little is known about the effect of light on their microbial communities. In the present work, 16S rRNA gene amplicon Nanopore sequencing and shotgun metagenomic sequencing were used to study the taxonomic and functional structure of the microbial community forming a biofilm on the inner wall of a laboratory-scale transparent anaerobic biodigester illuminated with natural sunlight. The biofilm was composed of microorganisms involved in the four metabolic processes needed for biogas production, and it was surprisingly rich in Rhodopseudomonas faecalis, a versatile bacterium able to carry out photoautotrophic metabolism when grown under anaerobic conditions. The results suggested that this bacterium, which is able to fix carbon dioxide, could be considered for use in transparent biogas fermenters in order to contribute to the production of optimized biogas with a higher CH4:CO2 ratio than the biogas produced in regular, opaque digesters. To the best of our knowledge, this is the first study characterising the phototrophic biofilm associated with illuminated bioreactors.


Assuntos
Biofilmes , Biocombustíveis/microbiologia , Microbiota/fisiologia , Processos Fototróficos , Anaerobiose , Archaea/classificação , Archaea/genética , Archaea/isolamento & purificação , Archaea/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Metagenoma , Microbiota/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Esgotos/microbiologia
9.
Cell Mol Life Sci ; 77(3): 415-432, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31768606

RESUMO

Heterogeneity is universally observed in all natural systems and across multiple scales. Understanding population heterogeneity is an intriguing and attractive topic of research in different disciplines, including microbiology and immunology. Microbes and mammalian immune cells present obviously rather different system-specific biological features. Nevertheless, as typically occurs in science, similar methods can be used to study both types of cells. This is particularly true for mathematical modeling, in which key features of a system are translated into algorithms to challenge our mechanistic understanding of the underlying biology. In this review, we first present a broad overview of the experimental developments that allowed observing heterogeneity at the single cell level. We then highlight how this "data revolution" requires the parallel advancement of algorithms and computing infrastructure for data processing and analysis, and finally present representative examples of computational models of population heterogeneity, from microbial communities to immune response in cells.


Assuntos
Imunidade/fisiologia , Microbiota/fisiologia , Algoritmos , Animais , Simulação por Computador , Humanos , Modelos Teóricos
10.
Chemosphere ; 238: 124682, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31524619

RESUMO

Plant growth-promoting bacteria (PGPB) are considered a promising tool to improve biomass production and water remediation by the aquatic plant, duckweed; however, no effective methodology is available to utilize PGPB in large hydroponic systems. In this study, we proposed a two-step cultivation process, which comprised of a "colonization step" and a "mass cultivation step," and examined its efficacy in both bucket-scale and flask-scale cultivation experiments. We showed that in the outdoor bucket-scale experiments using three kinds of environmental water, plants cultured through the two-step cultivation method with the PGPB strain, Acinetobacter calcoaceticus P23, yielded 1.9 to 2.3 times more biomass than the control (without PGPB inoculation). The greater nitrogen and phosphorus removals compared to control were also attained, indicating that this strategy is useful for accelerating nutrient removal by duckweed. Flask-scale experiments using non-sterile pond water revealed that inoculation of strain P23 altered duckweed surface microbial community structures, and the beneficial effects of the inoculated strain P23 could last for 5-10 d. The loss of the duckweed growth-promoting effect was noticeable when the colonization of strain P23 decreased in the plant. These observations suggest that the stable colonization of the plant with PGPB is the key for maintaining the accelerated duckweed growth and nutrient removal in this cultivation method. Overall, our results suggest the possibility of an improved duckweed production using a two-step cultivation process with PGPB.


Assuntos
Acinetobacter calcoaceticus/metabolismo , Araceae/crescimento & desenvolvimento , Araceae/microbiologia , Hidroponia/métodos , Microbiota/fisiologia , Biomassa , Água Doce , Nitrogênio/análise , Nutrientes , Fósforo/análise , Desenvolvimento Vegetal , Purificação da Água/métodos
11.
Chemosphere ; 238: 124596, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31524629

RESUMO

Deteriorated environmental conditions during the bioremediation of trichloroethene (TCE)-polluted groundwater cause decreased treatment efficiencies. This study assessed the effect of applying immobilized Clostridium butyricum (a hydrogen-producing bacterium) in silica gel on enhancing the reductive dechlorination efficiency of TCE with the slow polycolloid-releasing substrate (SPRS) supplement in groundwater. The responses of microbial communities with the immobilized system (immobilized Clostridium butyricum and SPRS amendments) were also characterized by the metagenomics assay. A complete TCE removal in microcosms was obtained within 30 days with the application of this immobilized system via reductive dechlorination processes. An increase in the population of Dehalococcoides spp. was observed using the quantitative polymerase chain reaction (qPCR) analysis. Results of metagenomics assay reveal that the microbial communities in the immobilized system were distinct from those in systems with SPRS only. Bacterial communities associated with TCE biodegradation also increased in microcosms treated with the immobilized system. The immobilized system shows a great potential to promote the TCE dechlorination efficiency, and the metagenomics-based approach provides detailed insights into dechlorinating microbial community dynamics. The results would be helpful in designing an in situ immobilized system to enhance the bioremediation efficiency of TCE-contaminated groundwater.


Assuntos
Chloroflexi/metabolismo , Clostridium butyricum/metabolismo , Água Subterrânea/química , Tricloroetileno/metabolismo , Biodegradação Ambiental , Chloroflexi/crescimento & desenvolvimento , Halogenação , Metagenômica , Microbiota/fisiologia , Sílica Gel
12.
BJOG ; 127(2): 275-284, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30932317

RESUMO

OBJECTIVE: To determine the effects on the vaginal microbiota of an oral probiotic preparation administered from early pregnancy. DESIGN: Randomised, double blind, placebo-controlled trial. SETTING: Four maternity units in the UK. POPULATION: Women aged 16 years or older recruited at 9-14 weeks' gestation. METHODS: Participants were randomly allocated to receive oral capsules of probiotic containing Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 each at 2.5 × 109 colony-forming units (CFUs) or placebo once daily from recruitment until the end of pregnancy. MAIN OUTCOME MEASURE: Rates of bacterial vaginosis (BV, defined as Nugent score ≥7) at 18-20 weeks' gestation compared by logistic regression adjusted for possible confounders. RESULTS: The primary analysis included 78% (238/304) of participants who initially consented (probiotic group 123, placebo group 115). Of these participants, 95% (227/238) reported an intake of 93% or more of the required number of capsules. The rates of BV did not differ between groups at 18-20 weeks' gestation (15% (19/123) in the probiotic group vs. 9% (10/115) in the placebo group, adjusted odds ratio 1.82, 95% confidence interval 0.64-5.19). There were also no differences between the groups in the proportion of women colonised with the probiotic strains, Escherichia coli, group B streptococci or other vaginal microbiota. There were no differences in the alpha diversity or composition of the bacterial communities between or within the probiotic and placebo groups at 9-14 and 18-20 weeks' gestation. CONCLUSIONS: Oral probiotics taken from early pregnancy did not modify the vaginal microbiota. TWEETABLE ABSTRACT: The oral probiotic preparation used in this study does not prevent BV in pregnant women.


Assuntos
Microbiota/fisiologia , Complicações Infecciosas na Gravidez/microbiologia , Probióticos/uso terapêutico , Vagina/microbiologia , Adulto , Método Duplo-Cego , Feminino , Humanos , Lactobacillus reuteri/efeitos dos fármacos , Lactobacillus rhamnosus/efeitos dos fármacos , Gravidez , Primeiro Trimestre da Gravidez , Vaginose Bacteriana/complicações , Vaginose Bacteriana/tratamento farmacológico , Vaginose Bacteriana/microbiologia , Adulto Jovem
14.
BJOG ; 127(2): 171-180, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31237400

RESUMO

BACKGROUND: Persistent infection with high-risk human papillomavirus can lead to cervical dysplasia and cancer. Recent studies have suggested associations between the composition of the vaginal microbiota, infection with human papillomavirus (HPV) and progression to cervical dysplasia and cancer. OBJECTIVE: To assess how specific cervico-vaginal microbiota compositions are associated with HPV infection, cervical dysplasia and cancer, we conducted a systematic review and network meta-analysis (registered in PROSPERO: CRD42018112862). SEARCH STRATEGY: PubMed, Web of science, Embase and Cochrane database. SELECTION CRITERIA: All original studies describing at least two community state types of bacteria (CST), based on molecular techniques enabling identification of bacteria, and reporting the association with HPV infection, cervical dysplasia and/or cervical cancer. DATA COLLECTION AND ANALYSIS: For the meta-analysis, a network map was constructed to provide an overview of the network relationships and to assess how many studies provided direct evidence for the different vaginal microbiota compositions and HPV, cervical dysplasia or cancer. Thereafter, the consistency of the model was assessed, and forest plots were constructed to pool and summarise the available evidence, presenting odds ratios and 95% confidence intervals. MAIN RESULTS: Vaginal microbiota dominated by non-Lactobacilli species or Lactobacillus iners were associated with three to five times higher odds of any prevalent HPV and two to three times higher for high-risk HPV and dysplasia/cervical cancer compared with Lactobacillus crispatus. CONCLUSIONS: These findings suggest an association between certain bacterial community types of the vaginal microbiota and HPV infection and HPV-related disease. This may be useful for guiding treatment options or serve as biomarkers for HPV-related disease. TWEETABLE ABSTRACT: This network meta-analysis suggests an association between different vaginal bacterial community types and the risk of HPV.


Assuntos
Neoplasia Intraepitelial Cervical/patologia , Lactobacillus/fisiologia , Microbiota/fisiologia , Papillomaviridae/fisiologia , Infecções por Papillomavirus/patologia , Neoplasias do Colo do Útero/patologia , Vagina/patologia , Neoplasia Intraepitelial Cervical/microbiologia , Feminino , Humanos , Meta-Análise em Rede , Infecções por Papillomavirus/microbiologia , RNA Ribossômico 16S , Neoplasias do Colo do Útero/microbiologia , Neoplasias do Colo do Útero/virologia , Vagina/microbiologia , Vagina/virologia
15.
BJOG ; 127(2): 129-137, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31325209

RESUMO

The hologenome concept of evolution is discussed, with special emphasis placed upon the microbiome of women. The microbiome is dynamic, changing under different conditions, and differs between women and men. Genetic variation occurs not only in the host, but also in the microbiome by the acquisition of novel microbes, the amplification of specific microbes, and horizontal gene transfer. The majority of unique genes in human holobionts are found in microbiomes, and mothers are responsible for transferring most of these to their offspring during birth, breastfeeding, and physical contact. Thus, mothers are likely to be the primary providers of the majority of genetic information to offspring via mitochondria and the microbiome. TWEETABLE ABSTRACT: Microbiomes differ between women and men. Most genes in humans are in the microbiome. Mothers transfer most of these genes to offspring.


Assuntos
Adaptação Biológica/fisiologia , Adaptação Fisiológica/fisiologia , Transferência Genética Horizontal/genética , Interações entre Hospedeiro e Microrganismos/fisiologia , Microbiota/fisiologia , Mães , Adaptação Biológica/genética , Adaptação Fisiológica/genética , Adulto , Animais , Evolução Biológica , Evolução Molecular , Feminino , Especiação Genética , Variação Genética , Hereditariedade , Humanos , Masculino , Microbiota/genética , Plantas , Gravidez
16.
BJOG ; 127(2): 230-238, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31397072

RESUMO

Women with congenital absolute uterine factor infertility (AUFI) often need vaginal restoration to optimise sexual function. Given their lack of procreative ability, little consideration has previously been given to the resultant vaginal microbiome (VM). Uterine transplantation (UTx) now offers the opportunity to restore these women's reproductive potential. The structure of the VM is associated with clinical and reproductive implications that are intricately intertwined with the process of UTx. Consideration of how vaginal restoration methods impact VM is now warranted and assessment of the VM in future UTx procedures is essential to understand the interrelation of the VM and clinical and reproductive outcomes. TWEETABLE ABSTRACT: The vaginal microbiome has numerous implications for clinical and reproductive outcomes in the context of uterine transplantation.


Assuntos
Anormalidades Congênitas/cirurgia , Infertilidade Feminina/cirurgia , Microbiota/fisiologia , Transplante de Órgãos , Útero/transplante , Vagina/microbiologia , Feminino , Humanos , RNA Ribossômico 16S/fisiologia , Técnicas de Reprodução Assistida , Útero/anormalidades , Útero/microbiologia , Vagina/fisiopatologia
17.
BJOG ; 127(2): 193-201, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31469215

RESUMO

OBJECTIVE: To characterise the bladder microbiota of continent adult women. DESIGN: Cross-sectional study of adult women who contributed catheterised urine samples, completed validated symptom questionnaires, and provided demographic data. SETTING: US academic medical centre. POPULATION: Well-characterised continent adult women. METHODS: Participants contributed symptoms questionnaires, demographic data, and catheterised urine samples that were analysed by enhanced urine culture methodology and 16S rRNA gene sequencing. MAIN OUTCOME MEASURES: Associations between demographics and microbial community state structures (urotypes, defined by the dominant taxon of each specimen). RESULTS: The bladder microbiota (urobiome) of a control group of 224 continent women were characterised, demonstrating variability in terms of urotype. The most common urotype was Lactobacillus (19%), which did not differ with any demographic. In contrast, the Gardnerella (P < 0.001) and Escherichia (P = 0.005) urotypes were more common in younger and older women, respectively. CONCLUSIONS: For urobiome research, enhanced culture methods and/or DNA sequencing are the preferred techniques for bacterial detection. The interpretation of clinical tests, such as the standard urine culture, should incorporate the knowledge that some women have Gardnerella or Escherichia urotypes without evidence of any clinical disorder. Clinical care strategies should preserve or restore the beneficial effects of the native urobiome, as disruption of that microbial community could result in unintended vulnerability to uropathogen invasion or opportunistic pathogen overgrowth. Longitudinal studies of urobiome responses to therapies should be encouraged. TWEETABLE ABSTRACT: In continent adult women bladder microbiome composition differs by age, with relevance for clinical practice.


Assuntos
Microbiota/genética , Bexiga Urinária/microbiologia , Sistema Urinário/microbiologia , Urina/microbiologia , Adulto , Estudos Transversais , Estudos de Avaliação como Assunto , Feminino , Humanos , Lactobacillus/genética , Microbiota/fisiologia , Pessoa de Meia-Idade , RNA Ribossômico 16S , Análise de Sequência de DNA , Bexiga Urinária/fisiologia
19.
BJOG ; 127(2): 264-274, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31573753

RESUMO

OBJECTIVE: To characterise vaginal bacterial composition in early pregnancy and investigate its relationship with first and second trimester miscarriages. DESIGN: Nested case-control study. SETTING: Queen Charlotte's and Chelsea Hospital, Imperial College Healthcare NHS Trust, London. POPULATION: 161 pregnancies: 64 resulting in first trimester miscarriage, 14 in second trimester miscarriage and 83 term pregnancies. METHODS: Prospective profiling and comparison of vaginal bacteria composition using 16S rRNA gene-based metataxonomics from 5 weeks' gestation in pregnancies ending in miscarriage or uncomplicated term deliveries matched for age, gestation and body mass index. MAIN OUTCOME MEASURES: Relative vaginal bacteria abundance, diversity and richness. Pregnancy outcomes defined as first or second trimester miscarriage, or uncomplicated term delivery. RESULTS: First trimester miscarriage associated with reduced prevalence of Lactobacillus spp.-dominated vaginal microbiota classified using hierarchical clustering analysis (65.6 versus 87.7%; P = 0.005), higher alpha diversity (mean Inverse Simpson Index 2.5 [95% confidence interval 1.8-3.0] versus 1.5 [1.3-1.7], P = 0.003) and higher richness 25.1 (18.5-31.7) versus 16.7 (13.4-20), P = 0.017), compared with viable pregnancies. This was independent of vaginal bleeding and observable before first trimester miscarriage diagnosis (P = 0.015). Incomplete/complete miscarriage associated with higher proportions of Lactobacillus spp.-depleted communities compared with missed miscarriage. Early pregnancy vaginal bacterial stability was similar between miscarriage and term pregnancies. CONCLUSIONS: These findings associate the bacterial component of vaginal microbiota with first trimester miscarriage and indicate suboptimal community composition is established in early pregnancy. While further studies are required to elucidate the mechanism, vaginal bacterial composition may represent a modifiable risk factor for first trimester miscarriage. TWEETABLE ABSTRACT: Vaginal bacterial composition in first trimester miscarriage is associated with reduced Lactobacillus spp. abundance and is independent of vaginal bleeding.


Assuntos
Aborto Espontâneo/microbiologia , Microbiota/fisiologia , Vagina/microbiologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Londres , Gravidez , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Estudos Prospectivos , RNA Ribossômico 16S
20.
World J Microbiol Biotechnol ; 35(12): 196, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784839

RESUMO

In this research, the dynamics of nitrogen transformation and bacterial community in malodorous river were investigated with different aeration depths. Computational flow dynamics (CFD) and Reynolds number (Re) were specially used to characterize the hydrodynamics condition under different aeration depths. The results indicated that aeration depth had vital impact on nitrogen transformation and bacterial community structure. It was found that a range of aeration depth (0.20-0.45 m above sediment-water interface) facilitated the removal of NH4+-N and TN with Re ranging between 6211 and 8930. Proteobacteria took over Firmicutes to become the predominant phylum (36-78%) under aeration, and the main subdivisions of γ-, ß- and δ-Proteobacteria also varied greatly with different aeration depths. Interestingly, there was a marked shift of the inferentially identified dominant functional role within Proteobacteria from organic-matter degradation to nitrogen metabolism and then to sulfur metabolism as well as the coupling of nitrogen and sulfur with the increase of disturbance. The redundancy analysis (RDA) further confirmed the importance of aeration disturbance in shaping bacterial community. These findings help to gain improved understanding of endogenous N-behavior and aquatic microbial ecology, and underline the need for integrating the hydrodynamics factors with microbial community.


Assuntos
Bactérias/metabolismo , Microbiota/fisiologia , Nitrogênio/metabolismo , Rios/química , Rios/microbiologia , Bactérias/classificação , Bactérias/genética , China , Sedimentos Geológicos/microbiologia , Oxigênio/metabolismo , Filogenia , RNA Ribossômico 16S , Enxofre/metabolismo
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