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1.
Methods Mol Biol ; 2374: 89-94, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34562245

RESUMO

The primary cilium is a microtubule-based organelle that projects from the surface of vertebrate cells. Defects in the biogenesis of or transport through primary cilia affect Hedgehog signaling, and many Hedgehog pathway components traffic through or accumulate in cilia. This protocol provides methods for immunofluorescence staining of cilia-accumulated Hh pathway components, such as Smoothened, in cultured NIH 3T3 cells.

2.
J Affect Disord ; 296: 434-442, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34606808

RESUMO

BACKGROUND: Preventive intervention can significantly reduce the human and economic costs of postpartum depression (PPD) compared with treatment post-diagnosis. However, identifying women with a high PPD risk and making a judgement as to the benefits of preventive intervention is a major challenge. METHODS: This is a retrospective study of parturients that underwent a cesarean delivery. Control group was used as development cohort and validation cohort to construct the risk prediction model of PPD and determine a risk threshold. Ketamine group and development cohort were used to verify the risk classification of parturients by evaluating whether the incidence of PPD decreased significantly after ketamine treatment in high-risk for PPD population. RESULTS: The AUC for the development cohort and validation cohort of the PPD prediction model were 0.751 (95%CI:0.700-0.802) and 0.748 (95%CI:0.680-0.816), respectively. A threshold of 19% PPD risk probability was determined, with a specificity and sensitivity in the validation cohort are 0.766 and 0.604, respectively. After matching the high-risk group and the low-risk group by propensity score, the results demonstrated that PPD incidence significantly reduced in the high-risk group following ketamine, versus non-ketamine, intervention (p < 0.01). In contrast, intervention in the low-risk group showed no significant difference in PPD outcomes (p > 0.01). LIMITATION: Randomized trials are needed to further verify the feasibility of the model and the thresholds proposed. CONCLUSION: This prediction model developed in this study shows utility in predicting PPD risk. Ketamine intervention significantly lowers PPD incidence in parturients with a risk classification threshold greater than 19%.

3.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(10): 1058-1063, 2021 Oct 15.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34719423

RESUMO

A 15-day-old boy was admitted to the hospital due to repeated convulsions for 14 days. The main clinical manifestations were uncontrolled seizures, hypoergia, feeding difficulties, limb hypotonia, and bilateral hearing impairment. Clinical neurophysiology showed reduced brainstem auditory evoked potential on both sides and burst-suppression pattern on electroencephalogram. Measurement of very-long-chain fatty acids in serum showed that C26:0 was significantly increased. Genetic testing showed a pathogenic compound heterozygous mutation, c.101C>T(p.Ala34Val) and c.1448_1460del(p.Ala483Aspfs*37), in the HSD17B4 gene. This article reports a case of D-bifunctional protein deficiency caused by HSD17B4 gene mutation and summarizes the epidemiological and clinical features, diagnosis, and treatment of this disease, with a focus on the differential diagnosis of this disease from Ohtahara syndrome.


Assuntos
Hipotonia Muscular , Deficiência de Proteína , Testes Genéticos , Humanos , Recém-Nascido , Masculino , Mutação , Proteína Multifuncional do Peroxissomo-2/genética , Deficiência de Proteína/genética
5.
Microbiol Resour Announc ; 10(47): e0086421, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34817213

RESUMO

Mortierella alpina is a filamentous fungus commonly associated with soil and is one of very few fungal species known to include strains with ice nucleation activity. Here, we report the draft genome sequence of the ice nucleation-active M. alpina strain LL118, isolated from aspen leaf litter collected in Alberta, Canada.

6.
Adv Mater ; : e2107855, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34808005

RESUMO

Encoding molecular ordering during liquid crystalline network (LCN) formation endows preprogrammed but fixed shape morphing in response to external stimuli. The incorporation of dynamic covalent bonds enables shape reprogramming but also permanently alters the network structures. Here, an entropic approach that can program complex shapes via directed solvent evaporation from an isotropic LCN organo-gel is discoursed. Different shapes can be erased and reprogrammed from the same LCN on demand depending on the modes of deformation of the organo-gel during solvent evaporation. The ability to decouple network synthesis and molecular alignment relaxes the requirements to LCN chemistry and alignment methods, allowing for the realization of a variety of origami/kirigami structures and 4D shape morphing of LCNs printed from the digital light processing technique with unattainable spatial and temporal controls. This article is protected by copyright. All rights reserved.

7.
Biotechnol Biofuels ; 14(1): 219, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34809676

RESUMO

BACKGROUND: Cellulase plays a key role in converting cellulosic biomass into fermentable sugar to produce chemicals and fuels, which is generally produced by filamentous fungi. However, most of the filamentous fungi obtained by natural breeding have low secretory capacity in cellulase production, which are far from meeting the requirements of industrial production. Random mutagenesis combined with adaptive laboratory evolution (ALE) strategy is an effective method to increase the production of fungal enzymes. RESULTS: This study obtained a mutant of Trichoderma afroharzianum by exposures to N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), Ethyl Methanesulfonate (EMS), Atmospheric and Room Temperature Plasma (ARTP) and ALE with high sugar stress. The T. afroharzianum mutant MEA-12 produced 0.60, 5.47, 0.31 and 2.17 IU/mL FPase, CMCase, pNPCase and pNPGase, respectively. These levels were 4.33, 6.37, 4.92 and 4.15 times higher than those of the parental strain, respectively. Also, it was found that T. afroharzianum had the same carbon catabolite repression (CCR) effect as other Trichoderma in liquid submerged fermentation. In contrast, the mutant MEA-12 can tolerate the inhibition of glucose (up to 20 mM) without affecting enzyme production under inducing conditions. Interestingly, crude enzyme from MEA-12 showed high enzymatic hydrolysis efficiency against three different biomasses (cornstalk, bamboo and reed), when combined with cellulase from T. reesei Rut-C30. In addition, the factors that improved cellulase production by MEA-12 were clarified. CONCLUSIONS: Overall, compound mutagenesis combined with ALE effectively increased the production of fungal cellulase. A super-producing mutant MEA-12 was obtained, and its cellulase could hydrolyze common biomasses efficiently, in combination with enzymes derived from model strain T. reesei, which provides a new choice for processing of bioresources in the future.

8.
Zhongguo Zhen Jiu ; 41(11): 1231-5, 2021 Nov 12.
Artigo em Chinês | MEDLINE | ID: mdl-34762376

RESUMO

OBJECTIVE: To compare the clinical efficacy of abdominal acupoint thread embedding therapy based on "brain-intestinal connection" combined with donepezil hydrochloride tablets and oral donepezil hydrochloride tablets alone for mild-to-moderate Alzheimer's disease (AD) and observe its effects on amyloid precursor protein (APP) and ß-amyloid protein1-42 (Aß1-42). METHODS: Sixty patients with AD were randomly divided into an observation group (30 cases, 3 cases dropped off) and a control group (30 cases, 3 cases dropped off). The patients in the control group were treated with donepezil hydrochloride tablets (5 mg per day); based on the treatment in the control group, the patients in the observation group were treated with abdominal acupoint thread embedding therapy at Zhongwan (CV 12), Xiawan (CV 10), Huaroumen (ST 24), Wailing (ST 26), Daheng (SP 15), etc., once every 10 days. Both groups were treated for 2 months. The mini-mental state examination (MMSE), Alzheimer's disease assessment scale-cognitive subscale (ADAS-Cog), activity of daily living scale (ADL), neuropsychiatric inventory questionnaire (NPI) as well as the serum levels of APP and Aß1-42 were observed before and after treatment in the two groups. RESULTS: After treatment, the MMSE scores in the two groups were higher than those before treatment (P<0.05), and the ADAS-Cog, ADL and NPI scores were lower than those before treatment (P<0.05). After treatment, the MMSE score in the observation group was higher than that in the control group (P<0.05), and the ADAS-Cog, ADL and NPI scores were lower than those in the control group (P<0.05). After treatment, the serum levels of APP and Aß1-42 were lower than those before treatment (P<0.05), and the serum levels of APP and Aß1-42 in the observation group was lower than those in the control group (P<0.05). CONCLUSION: The abdominal acupoint thread embedding therapy based on the theory of "brain-intestinal connection" combined with donepezil hydrochloride tablets can improve cognitive function, self-care ability of daily life and mental behavior, and reduce the serum levels of APP and Aß1-42 in patients with mild-to-moderate AD, which have superior clinical effect to donepezil hydrochloride tablets alone.


Assuntos
Doença de Alzheimer , Pontos de Acupuntura , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides , Precursor de Proteína beta-Amiloide , Encéfalo , Donepezila , Humanos , Fragmentos de Peptídeos
9.
Artigo em Inglês | MEDLINE | ID: mdl-34769764

RESUMO

Internet media may exacerbate public confusion and anxiety about COVID-19. New media health literacy (NMHL) is considered to play a protective role against health-related misinformation from the media for individuals to maintain their health. The current study aims to examine the relationship among Taiwanese adults' NMHL, health status, anxiety, and prevention behaviors during the COVID-19 pandemic. This cross-sectional study was conducted through an online survey, and 342 responses were included in the analysis. The survey tools include Health Status, COVID-19-Related New Media Health Literacy, COVID-19 Anxiety, and COVID-19 Preventive Behaviors. The research showed that both functional and critical prosuming literacy had positive relationships with health status. Functional consumption literacy had a weak negative correlation with COVID-19 anxiety. Furthermore, critical consumption literacy had a positive relationship with COVID-19 preventive behaviors. Therefore, individuals' health, anxiety, and prevention behaviors are affected by different aspects of COVID-19-related new media health literacy. Compared to their consuming media literacy, Taiwanese adults have insufficient prosuming media literacy in regard to COVID-19 health issues.


Assuntos
COVID-19 , Letramento em Saúde , Adulto , Ansiedade/epidemiologia , Ansiedade/prevenção & controle , Estudos Transversais , Nível de Saúde , Humanos , Pandemias , SARS-CoV-2 , Inquéritos e Questionários , Taiwan/epidemiologia
10.
J Clin Nurs ; 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34738288

RESUMO

AIMS AND OBJECTIVES: Review the content, quality and effect of breast cancer screening decision aids (BCS-DAs) in women approximately 50 years of age to provide a basis for the development of DAs. BACKGROUND: Breast cancer screening (BCS) decisions are complex and should vary depending on a woman's risk of breast cancer and her values and preferences. Decision aids (DAs) can help support women and medical staff in shared decision-making (SDM) when solving BCS problems. DESIGN: Systematic review and meta-analysis. METHODS: Four databases were searched starting at the time of establishment of the database to March 2021. The PRISMA checklist was followed. The meta-analysis was carried out using Review Manager 5.3 software. The quality of the studies was assessed using the risk of bias tool recommended by the Cochrane Handbook. The quality of the DAs was assessed using the International Standards for Decision Aid (IPDASi v4.0). RESULTS: The search strategy obtained 2024 references. After abstraction and full text screening, a total of seven studies were included. This article systematically reviews the content, quality and effectiveness of DAs in seven RCTs in helping women to make BCS decisions. The DAs were mostly in paper or online form and displayed disease screening information, analysed the benefits and harms of options and clarified the value to patients. Among all the DAs, only one met the minimum quality standards of IPDASi v4.0. Comprehensive analysis shows that DAs can significantly improve knowledge and increase the proportion of women who make informed choices, but they have no effect on screening attitude, intention, decision conflict or regret. CONCLUSIONS: In the future, nurses should be encouraged to develop DAs in accordance with strict standards and to make them applicable to young women of different backgrounds. RELEVANCE TO CLINICAL PRACTICE: The result may be provide a basis for the development of DAs to promote women's informed screening choices.

11.
Ann Palliat Med ; 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34775768

RESUMO

BACKGROUND: Corona virus disease 2019 (COVID-19) showed a significant difference in case fatality rate between different regions at the early stage of the epidemic. In addition to the well-known factors such as age structure, detection efficiency, and race, there was also a possibility that medical resource shortage caused the increase of the case fatality rate in some regions. METHODS: Medline, Cochrane Library, Embase, Web of Science, CBM, CNKI, and Wan fang of identified articles were searched through 29 June 2020. Cohort studies and case series with duration information on COVID-19 patients were included. Two independent reviewers extracted the data using a standardized data collection form and assessed the risk of bias. Data were synthesized through description and analysis methods including a meta-analysis. RESULTS: A total of 109 articles were retrieved. The time interval from onset to the first medical visit of COVID-19 patients in China was 3.38±1.55 days (corresponding intervals in Hubei province, non-Hubei provinces, Wuhan, Hubei provinces without Wuhan were 4.22±1.13, 3.10±1.57, 4.20±0.97, and 4.34±1.72 days, respectively). The time interval from onset to the hospitalization of COVID-19 patients in China was 8.35±6.83 days (same corresponding intervals were 12.94±7.43, 4.17±1.45, 14.86±7.12, and 5.36±1.19 days, respectively), and when it was outside China, this interval was 5.27±1.19 days. DISCUSSION: In the early stage of the COVID-19 epidemic, patients with COVID-19 did not receive timely treatment, resulting in a higher case fatality rate in Hubei province, partly due to the relatively insufficient and unequal medical resources. This research suggested that additional deaths caused by the out-of-control epidemic can be avoided if prevention and control work is carried out at the early stage of the epidemic. TRIAL REGISTRATION: CRD42020195606.

12.
J Chin Med Assoc ; 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34759208

RESUMO

BACKGROUND: In patients with atrial fibrillation (AF) and acute coronary syndrome (ACS) or undergoing percutaneous coronary intervention (PCI), choosing the most appropriate antithrombotic treatment remains a dilemma. We aimed to compare the relative efficacy and safety outcomes of antithrombotic drugs in patients with AF after undergoing PCI or ACS. METHODS: Randomized controlled trials were systematically searched on PubMed, EMBASE, and the Cochrane Library. Five studies (11,532 patients) were included in the network meta-analysis (NMA). Trial sequential analysis (TSA) was performed to assess the reliability and conclusiveness of the meta-analysis comparing the dual antithrombotic therapy strategies with the triple antithrombotic therapy strategy. RESULTS: Compared with vitamin K antagonist (VKA) + dual antiplatelet therapy (DAPT), novel oral anticoagulant (NOAC) + P2Y12 inhibitor was associated with a significantly better trial-defined primary safety outcome (odds ratio: 0.53; 95% CI: 0.31 - 0.90) and the lowest probability of thrombolysis in myocardial infarction (TIMI) major bleeding and intracranial hemorrhage using the cumulative ranking technique. In patients omitting aspirin, TSA demonstrated conclusive evidence with significant decreases in all safety outcomes and inconclusive evidence with a non-significant increase in in-stent thrombosis (risk ratio: 1.32; TSA-adjusted 95% CI: 0.54 - 3.24) and myocardial infarction (risk ratio: 1.19; TSA-adjusted 95% CI: 0.84 - 1.68). CONCLUSION: In patients with AF receiving PCI or with ACS, NOAC + P2Y12 inhibitor was associated with the lowest bleeding risk but resulted in a statistically non-significant, numerically greater risk for stent thrombosis and myocardial infarction, suggesting that triple antithrombotic therapy (TAT) should still be an option for certain patients at a high risk of stent thrombosis or myocardial infarction.

13.
J Forensic Sci ; 2021 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-34606109

RESUMO

In this study, we aimed to explore the possibility of DNA analysis of areca nut as material evidence and the value of short tandem repeat (STR) typing of areca nut as material evidence under the condition of simulating external environment. In this study, water soaking, soil burial, sun exposure, and wet environment were used to treat areca nut residues. Chelex 100 was used to extract DNA, the PowerPlex21 kit to amplify, and the ABI PRISM® 310 Genetic Analyzer to analyze the DNA of areca nut residues. DNA and STR typing were performed to analyze the residue after chewing. The results showed that the number of residual sites decreased with time under the conditions of water soaking, soil burial, sun exposure, and wet environment. Thus, areca nut can be used as forensic material evidence for DNA analysis and individual identification.

14.
Artigo em Inglês | MEDLINE | ID: mdl-34595708

RESUMO

This study sought to identify the spatial, temporal, and spatiotemporal clusters of COVID-19 cases in 366 cities in mainland China with the highest risks and to explore the possible influencing factors of imported risks and environmental factors on the spatiotemporal aggregation, which would be useful to the design and implementation of critical preventative measures. The retrospective analysis of temporal, spatial, and spatiotemporal clustering of COVID-19 during the period (January 15 to February 25, 2020) was based on Kulldorff's time-space scanning statistics using the discrete Poisson probability model, and then the logistic regression model was used to evaluate the impact of imported risk and environmental factors on spatiotemporal aggregation. We found that the spatial distribution of COVID-19 cases was nonrandom; the Moran's I value ranged from 0.017 to 0.453 (P < 0.001). One most likely cluster and three secondary likely clusters were discovered in spatial cluster analysis. The period from February 2 to February 9, 2020, was identified as the most likely cluster in the temporal cluster analysis. One most likely cluster and seven secondary likely clusters were discovered in spatiotemporal cluster analysis. Imported risk, humidity, and inhalable particulate matter PM2.5 had a significant impact on temporal and spatial accumulation, and temperature and PM10 had a low correlation with the spatiotemporal aggregation of COVID-19. The information is useful for health departments to develop a better prevention strategy and potentially increase the effectiveness of public health interventions.

15.
Sci Total Environ ; 806(Pt 2): 150647, 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34597560

RESUMO

Landfill are important reservoirs of antibiotics and antibiotic resistance genes (ARGs). They harbor diverse contaminants, such as heavy metals and persistent organic chemicals, complex microbial consortia, and anaerobic degradation processes, which facilitate the occurrence, development, and transfer of ARGs and antibiotic resistant bacteria (ARB). The main concern is that antibiotics and developed ARGs and ARB may transfer to the local environment via leachate and landfill leakage. In this paper, we provide an overview of established studies on antibiotics and ARGs in landfills, summarize the origins and distribution of antibiotics and ARGs, discuss the linkages among various antibiotics, ARGs, and bacterial communities as well as the influencing factors of ARGs, and evaluate the current treatment processes of antibiotics and ARGs. Finally, future research is proposed to fill the current knowledge gaps, which include mechanisms for the development and transmission of antibiotic resistance, as well as efficient treatment approaches for antibiotic resistance.

16.
J Crohns Colitis ; 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34628497

RESUMO

BACKGROUND AND AIMS: Disruption of the intestinal barrier of the digestive tract is a common pathophysiological change in the elderly, which may partly contribute to gut dysfunction and inflammatory bowel disease. This study aimed to discover new interactive epigenetic regulation patterns involved in intestinal barrier dysfunction and colitis in elderly populations. METHODS: Intestinal barrier function and structure were evaluated in naturally aging mice and elderly people. High-throughput analysis was performed on colonic tissues from humans and mice. The synergistic roles of miR-1-3p and miR-124-3p were identified using microRNA mimic/agomirs. Related genes were examined in biopsies of old IBD patients. RESULTS: A defective mucus barrier was observed before mucosal microstructural damage during aging. Elevated miR-1-3p expression in the colons of older individuals impaired mucus barrier by directly targeting T-synthase, similar to the mechanism of miR-124-3p, which we reported previously. Importantly, the synergistic effect of a half dose of each microRNA supplement on T-synthase and CDK4/6 was stronger than that of a full dose of miR-1-3p or miR-124-3p alone, and mice cotreated with two microRNAs showed greater susceptibility to chemical-induced colitis than mice treated with either microRNA alone. These two microRNAs were up-expressed in old IBD patients. CONCLUSIONS: The slight increases in miR-1-3p and miR-124-3p expression with aging may be important contributors to the breakdown of intestinal homeostasis by targeting divergent genes in different cells. These data reveal the potential ability of multiple microRNAs to exert synergistic effects to damage the intestinal barrier and promote inflammatory bowel disease development in elderly populations.

17.
Folia Neuropathol ; 59(3): 239-248, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34628789

RESUMO

Increasing evidence highlights that microRNAs (miRNAs) drive glioma initiation and development. Nevertheless, the underlying role of miR-21-5p in glioma is elusive. Hence, we evaluated the underlying role of miR-21-5p in glioma progression. Microarray data analysis provided data indicating that the miR-21-5p level was elevated in glioma. Silenced miR-21-5p suppressed glioma cell growth and invasion. Additionally, our results disclosed that ten-eleven translocation 1 (TET1) was directly targeted by miR-21-5p. Furthermore, antagomir-21-5p restrained glioma cell growth in a xenograft tumour model. In rescue experiments, knockdown of TET1 neutralized miR-21-5p silence-mediated inhibitory function on glioma cell aggressiveness. Taken together, miR-21-5p exerted its carcinogenic effect in glioma cell growth and invasin by targeting TET1.

18.
Molecules ; 26(20)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34684854

RESUMO

CO2-switchable oligomeric surfactants have good viscosity-reducing properties; however, the complex synthesis of surfactants limits their application. In this study, a CO2-switchable "pseudo"-tetrameric surfactant oleic acid (OA)/cyclic polyamine (cyclen) was prepared by simple mixing and subsequently used to reduce the viscosity of heavy oil. The surface activity of OA/cyclen was explored by a surface tensiometer and a potential for viscosity reduction was revealed. The CO2 switchability of OA/cyclen was investigated by alternately introducing CO2 and N2, and OA/cyclen was confirmed to exhibit a reversible CO2-switching performance. The emulsification and viscosity reduction analyses elucidated that a molar ratio of OA/cyclen of 4:1 formed the "pseudo"-tetrameric surfactants, and the emulsions of water and heavy oil with OA/cyclen have good stability and low viscosity and can be destabilized quickly by introducing CO2. The findings reported in this study reveal that it is feasible to prepare CO2-switchable pseudo-tetrameric surfactants with viscosity-reducing properties by simple mixing, thus providing a pathway for the emulsification and demulsification of heavy oil by using the CO2-switchable "pseudo"-oligomeric surfactants.

19.
Nucleic Acids Res ; 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34718746

RESUMO

Noncanonical nucleic acid structures, such as G-quadruplex (G4) and i-Motif (iM), have attracted increasing research interests because of their unique structural and binding properties, as well as their important biological activities. To date, thousands of small molecules that bind to varying G4/iM structures have been designed, synthesized and tested for diverse chemical and biological uses. Because of the huge potential and increasing research interests on G4-targeting ligands, we launched the first G4 ligand database G4LDB in 2013. Here, we report a new version, termed G4LDB 2.2 (http://www.g4ldb.com), with upgrades in both content and function. Currently, G4LDB2.2 contains >3200 G4/iM ligands, ∼28 500 activity entries and 79 G4-ligand docking models. In addition to G4 ligand library, we have also added a brand new iM ligand library to G4LDB 2.2, providing a comprehensive view of quadruplex nucleic acids. To further enhance user experience, we have also redesigned the user interface and optimized the database structure and retrieval mechanism. With these improvements, we anticipate that G4LDB 2.2 will serve as a comprehensive resource and useful research toolkit for researchers across wide scientific communities and accelerate discovering and validating better binders and drug candidates.

20.
Front Microbiol ; 12: 743827, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34707594

RESUMO

Methane production during solid waste decomposition is a typical methanogen-mediated and enzyme-catalyzed anaerobic digestion (AD). Methanogen community dynamics and metabolic diversity during the decomposition are not known. In this study, we investigated methanogen community dynamics and methanogenic pathways during solid waste decomposition in a bioreactor using high-throughput Illumina MiSeq sequencing and phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt), respectively. We also related the methanogen community differences with solid waste and leachate physiochemical parameters. Results showed that the percentage of biodegradable matter (BDM) in solid waste decreased from 55 ± 5% in aerobic phase (AP) to 30 ± 2% in anaerobic acid phase (ACP), and to 13 ± 11% in methanogenic phase (MP), resulting in 76% BDM consumption by microbes. Methanogen community structure varied in AP, ACP, and MP, showing that Methanomicrobiales and Methanosarcinales were dominant in AP and MP and archaea E2 was abundant in ACP. Each phase had abundant core methanogen orders, genera, and species with significant difference (p < 0.05). Redundancy analysis showed that biochemical oxygen demand (BOD5) and nitrate significantly influenced methanogen community composition, suggesting that methanogen community structure is nutrient-dependent. Two methanogenic pathways including acetoclastic and hydrogenotrophic pathways with associated functional genes differed at three phases. ACP had the lowest abundance of these genes, indicating that methanogenesis was inhibited in acidogenesis. Abundant hydrogenotrophic and acetoclastic methanogenesis functional genes in MP and AP are in response to the abundance of Methanomicrobiales and Methanosarcinales. The findings provide previously unidentified insight into the mechanism of methanogen community structure and function during solid waste bioconversion for methane.

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