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  1. Article ; Online: Revisiting methane-dependent denitrification.

    Wu, Mengxiong / Liu, Tao / Guo, Jianhua

    Trends in microbiology

    2024  

    Abstract: Methane-dependent denitrification links the global nitrogen and methane cycles. Since its initial discovery in 2006, this process has been understood to involve a division of labor between an archaeal group and a bacterial group, which sequentially ... ...

    Abstract Methane-dependent denitrification links the global nitrogen and methane cycles. Since its initial discovery in 2006, this process has been understood to involve a division of labor between an archaeal group and a bacterial group, which sequentially perform nitrate and nitrite reduction, respectively. Yao et al. have now revised this paradigm by identifying a Methylomirabilis bacterium capable of performing methane-dependent complete denitrification on its own.
    Language English
    Publishing date 2024-03-22
    Publishing country England
    Document type Journal Article
    ZDB-ID 1158963-2
    ISSN 1878-4380 ; 0966-842X
    ISSN (online) 1878-4380
    ISSN 0966-842X
    DOI 10.1016/j.tim.2024.03.007
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Non-caloric artificial sweeteners exhibit antimicrobial activity against bacteria and promote bacterial evolution of antibiotic tolerance.

    Yu, Zhigang / Guo, Jianhua

    Journal of hazardous materials

    2022  Volume 433, Page(s) 128840

    Abstract: Non-caloric artificial sweeteners are being widely used as safe table sugar substitutes with highly intensive sweetness but low calories. Previous studies have suggested that some of the sweeteners can alter the gut microbiota composition and promote ... ...

    Abstract Non-caloric artificial sweeteners are being widely used as safe table sugar substitutes with highly intensive sweetness but low calories. Previous studies have suggested that some of the sweeteners can alter the gut microbiota composition and promote horizontal transfer of antibiotic resistance genes across bacterial genera. However, little is known about whether these sweeteners could show antibiotic-like antimicrobial activity against bacteria, especially gut relevant bacteria. Whether they could affect evolutional trajectory of antibiotic resistance or tolerance in bacteria is also not clear yet. Here we investigated four commonly used artificial sweeteners (saccharin, sucralose, aspartame, and acesulfame potassium) against both Gram-negative (Escherichia coli and Klebsiella pneumoniae) and positive (Bacillus subtilis) strains. Results show that all four sweeteners exhibit antimicrobial effects on these strains. The antimicrobial mechanism is due to increased reactive oxygen species (ROS) and cell envelope damage. Compared to sucrose and glucose, the treatment of artificial sweeteners stimulates bacterial efflux pumps and promotes bacterial evolution of antibiotic tolerance. Collectively, our finding provides insights into roles of artificial sweeteners in the emergence of antibiotic tolerance and calls for a re-evaluation of risks due to their intensive usage.
    MeSH term(s) Anti-Bacterial Agents/pharmacology ; Aspartame/pharmacology ; Bacteria ; Escherichia coli/genetics ; Saccharin/pharmacology ; Sweetening Agents/pharmacology
    Chemical Substances Anti-Bacterial Agents ; Sweetening Agents ; Saccharin (FST467XS7D) ; Aspartame (Z0H242BBR1)
    Language English
    Publishing date 2022-04-04
    Publishing country Netherlands
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1491302-1
    ISSN 1873-3336 ; 0304-3894
    ISSN (online) 1873-3336
    ISSN 0304-3894
    DOI 10.1016/j.jhazmat.2022.128840
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article: Non-caloric artificial sweeteners exhibit antimicrobial activity against bacteria and promote bacterial evolution of antibiotic tolerance

    Yu, Zhigang / Guo, Jianhua

    Journal of hazardous materials. 2022 July 05, v. 433

    2022  

    Abstract: Non-caloric artificial sweeteners are being widely used as safe table sugar substitutes with highly intensive sweetness but low calories. Previous studies have suggested that some of the sweeteners can alter the gut microbiota composition and promote ... ...

    Abstract Non-caloric artificial sweeteners are being widely used as safe table sugar substitutes with highly intensive sweetness but low calories. Previous studies have suggested that some of the sweeteners can alter the gut microbiota composition and promote horizontal transfer of antibiotic resistance genes across bacterial genera. However, little is known about whether these sweeteners could show antibiotic-like antimicrobial activity against bacteria, especially gut relevant bacteria. Whether they could affect evolutional trajectory of antibiotic resistance or tolerance in bacteria is also not clear yet. Here we investigated four commonly used artificial sweeteners (saccharin, sucralose, aspartame, and acesulfame potassium) against both Gram-negative (Escherichia coli and Klebsiella pneumoniae) and positive (Bacillus subtilis) strains. Results show that all four sweeteners exhibit antimicrobial effects on these strains. The antimicrobial mechanism is due to increased reactive oxygen species (ROS) and cell envelope damage. Compared to sucrose and glucose, the treatment of artificial sweeteners stimulates bacterial efflux pumps and promotes bacterial evolution of antibiotic tolerance. Collectively, our finding provides insights into roles of artificial sweeteners in the emergence of antibiotic tolerance and calls for a re-evaluation of risks due to their intensive usage.
    Keywords Bacillus subtilis ; Escherichia coli ; Klebsiella pneumoniae ; acesulfame potassium ; antibiotic resistance ; antimicrobial properties ; aspartame ; evolution ; glucose ; intestinal microorganisms ; reactive oxygen species ; saccharin ; sucralose ; sucrose ; sweetness ; white sugar
    Language English
    Dates of publication 2022-0705
    Publishing place Elsevier B.V.
    Document type Article
    ZDB-ID 1491302-1
    ISSN 1873-3336 ; 0304-3894
    ISSN (online) 1873-3336
    ISSN 0304-3894
    DOI 10.1016/j.jhazmat.2022.128840
    Database NAL-Catalogue (AGRICOLA)

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  4. Article ; Online: Rock Mechanical Properties and Wellbore Stability of Fractured Dolomite Formations.

    Guo, Jianhua / She, Chaoyi / Liu, Houbin / Cui, Shuai

    ACS omega

    2023  Volume 8, Issue 38, Page(s) 35152–35166

    Abstract: During the drilling process in the dolomite formation of the Leikoupo formation in western Sichuan, downhole obstruction frequently occurs, which seriously hinders the efficient development of oil and gas resources on site. In view of the problems of ... ...

    Abstract During the drilling process in the dolomite formation of the Leikoupo formation in western Sichuan, downhole obstruction frequently occurs, which seriously hinders the efficient development of oil and gas resources on site. In view of the problems of borehole stability existing in this type of formation, the geological characteristics, underground complexity, and fracture development of the research block were systematically identified and analyzed, and the physical parameters and mechanical properties of the rock were defined through physical and chemical tests and an understanding of the mechanical properties of the rock. These studies revealed the mechanism of borehole instability and the main factors influencing fractured dolomite formation. Finally, a model of borehole collapse pressure within fractured dolomite formation was established by selecting the appropriate strength criterion as the criterion of borehole instability. The results show that the dolomite fractures of the Leikoupo formation are relatively developed, the formation is dominated by low-angle fractures, and the core integrity is not high. The development of formation fractures has an obvious effect on the mechanical strength of rock, which decreases to different degrees with the decrease in the integrity coefficient of the rock mass, and the anisotropy of the rock's mechanical strength is obvious. The empirical parameters of the generalized Hoek-Brown (H-B) strength criterion were quantified by introducing rock mass acoustic data, and the accuracy of the improved generalized H-B strength criterion was evaluated using triaxial test data. Taking the M-C criterion, the generalized H-B criterion based on acoustic wave, the D-P criterion, and the weak surface strength criterion as wellbore instability criteria, combined with the distribution of wellbore stress, a prediction model of wellbore stability considering the degree of dolomite formation fragmentation was established. The results demonstrate that the generalized H-B criterion model based on acoustic waves can be used to evaluate the wellbore stability of dolomite fracture formation with more than one group of fractures. These research results have certain guiding significance for efficient and safe drilling in fractured dolomite formations.
    Language English
    Publishing date 2023-09-11
    Publishing country United States
    Document type Journal Article
    ISSN 2470-1343
    ISSN (online) 2470-1343
    DOI 10.1021/acsomega.3c04768
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Microbial Stratification Affects Conversions of Nitrogen and Methane in Biofilms Coupling Anammox and n-DAMO Processes.

    Liu, Tao / Hu, Shihu / Yuan, Zhiguo / Guo, Jianhua

    Environmental science & technology

    2023  Volume 57, Issue 11, Page(s) 4608–4618

    Abstract: A methane-based membrane biofilm reactor (MBfR) has a suitable configuration to incorporate anammox and nitrite/nitrate-dependent anaerobic methane oxidation (n-DAMO) processes because of its high gas-transfer efficiency and efficient biomass retention. ... ...

    Abstract A methane-based membrane biofilm reactor (MBfR) has a suitable configuration to incorporate anammox and nitrite/nitrate-dependent anaerobic methane oxidation (n-DAMO) processes because of its high gas-transfer efficiency and efficient biomass retention. In this study, the spatial distribution of microorganisms along with the biofilm depth in methane-based MBfRs was experimentally revealed, showing the dominance of anammox bacteria, n-DAMO bacteria, and n-DAMO archaea in the outer layer, middle layer, and inner layer of biofilms, respectively. The long-term and short-term experimental investigations in conjunction with mathematical modeling collectively revealed that microorganisms living in the outer layer of biofilms tend to use substrates from wastewater, while microorganisms inhabiting the inner layer of biofilms tend to use substrates originating from biofilm substratum. Specifically, anammox bacteria dominating the biofilm surface preferentially removed the nitrite provided from wastewater, while n-DAMO bacteria mostly utilized the nitrite generated from n-DAMO archaea as these two methane-related populations spatially clustered together inside the biofilm. Likewise, the methane supplied from the membrane was mostly consumed by n-DAMO archaea, while the dissolved methane in wastewater would be primarily utilized by n-DAMO bacteria. This study offers novel insights into the impacts of microbial stratification in biofilm systems, not only expanding the fundamental understanding of biofilms and microbial interactions therein but also providing a rationale for the potential applications of methane-based MBfRs in sewage treatment.
    MeSH term(s) Nitrates ; Nitrites ; Wastewater ; Methane ; Nitrogen ; Anaerobic Ammonia Oxidation ; Anaerobiosis ; Denitrification ; Bacteria ; Archaea ; Biofilms ; Oxidation-Reduction ; Bioreactors/microbiology
    Chemical Substances Nitrates ; Nitrites ; Wastewater ; Methane (OP0UW79H66) ; Nitrogen (N762921K75)
    Language English
    Publishing date 2023-02-24
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1520-5851
    ISSN (online) 1520-5851
    DOI 10.1021/acs.est.2c07294
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Nitrite Oxidation in Wastewater Treatment: Microbial Adaptation and Suppression Challenges.

    Su, Zicheng / Liu, Tao / Guo, Jianhua / Zheng, Min

    Environmental science & technology

    2023  Volume 57, Issue 34, Page(s) 12557–12570

    Abstract: Microbial nitrite oxidation is the primary pathway that generates nitrate in wastewater treatment systems and can be performed by a variety of microbes: namely, nitrite-oxidizing bacteria (NOB). Since NOB were first isolated 130 years ago, the ... ...

    Abstract Microbial nitrite oxidation is the primary pathway that generates nitrate in wastewater treatment systems and can be performed by a variety of microbes: namely, nitrite-oxidizing bacteria (NOB). Since NOB were first isolated 130 years ago, the understanding of the phylogenetical and physiological diversities of NOB has been gradually deepened. In recent endeavors of advanced biological nitrogen removal, NOB have been more considered as a troublesome disruptor, and strategies on NOB suppression often fail in practice after long-term operation due to the growth of specific NOB that are able to adapt to even harsh conditions. In line with a review of the history of currently known NOB genera, a phylogenetic tree is constructed to exhibit a wide range of NOB in different phyla. In addition, the growth behavior and metabolic performance of different NOB strains are summarized. These specific features of various NOB (e.g., high oxygen affinity of
    MeSH term(s) Wastewater ; Nitrification ; Phylogeny ; Acclimatization ; Nitrites
    Chemical Substances Wastewater ; Nitrites
    Language English
    Publishing date 2023-08-17
    Publishing country United States
    Document type Journal Article ; Review ; Research Support, Non-U.S. Gov't
    ISSN 1520-5851
    ISSN (online) 1520-5851
    DOI 10.1021/acs.est.3c00636
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Simultaneous dissolved methane and nitrogen removal from low-strength wastewater using anaerobic granule-based sequencing batch reactor.

    Liu, Tao / Hu, Shihu / Yuan, Zhiguo / Guo, Jianhua

    Water research

    2023  Volume 242, Page(s) 120194

    Abstract: Anaerobic treatment of mainstream wastewater has been proposed as a promising solution to enhance bioenergy recovery for wastewater treatment plants (WWTPs). However, the limited organics for downstream nitrogen removal and emissions of dissolved methane ...

    Abstract Anaerobic treatment of mainstream wastewater has been proposed as a promising solution to enhance bioenergy recovery for wastewater treatment plants (WWTPs). However, the limited organics for downstream nitrogen removal and emissions of dissolved methane into the atmosphere are two major barriers to the broad application of anaerobic wastewater treatment. This study aims to develop a novel technology to overcome these two challenges by achieving simultaneous removal of dissolved methane and nitrogen, and unravel the microbial competitions underpinning the process from the microbial and kinetic perspectives. To this end, a laboratory granule-based sequencing batch reactor (GSBR) coupling anammox and nitrite/nitrate-dependent anaerobic methane oxidation (n-DAMO) microorganisms was developed to treat wastewater mimicking effluent from mainstream anaerobic treatment. The GSBR achieved high-level nitrogen and dissolved methane removal rates (> 250 mg N/L/d and > 65 mg CH
    MeSH term(s) Wastewater ; Nitrites/metabolism ; Nitrates/metabolism ; Anaerobiosis ; Denitrification ; Methane/metabolism ; Nitrogen/metabolism ; Bioreactors/microbiology ; Oxidation-Reduction ; Oxidants ; Ammonium Compounds/metabolism
    Chemical Substances Wastewater ; Nitrites ; Nitrates ; Methane (OP0UW79H66) ; Nitrogen (N762921K75) ; Oxidants ; Ammonium Compounds
    Language English
    Publishing date 2023-06-08
    Publishing country England
    Document type Journal Article
    ZDB-ID 202613-2
    ISSN 1879-2448 ; 0043-1354
    ISSN (online) 1879-2448
    ISSN 0043-1354
    DOI 10.1016/j.watres.2023.120194
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Correlation of microbial community structure and volatile flavor compounds during corn yellow wine fermentation.

    Guo, Jianhua / Zhao, Xiaoxu / Shi, Jie

    Biotechnology progress

    2023  Volume 40, Issue 1, Page(s) e3408

    Abstract: High-throughput sequencing was used to define microbial community structure and GC-MS to identify volatile flavor substances during fermentation of corn yellow wine, and results were analyzed by multivariate statistical analysis. Seventeen bacterial ... ...

    Abstract High-throughput sequencing was used to define microbial community structure and GC-MS to identify volatile flavor substances during fermentation of corn yellow wine, and results were analyzed by multivariate statistical analysis. Seventeen bacterial phyla, 239 bacterial genera, 4 fungal phyla, and 18 fungal genera were found and changes in community structure occurred during fermentation. Twenty-four volatile flavor substances, including 14 esters and 5 alcohols, were detected and changes during fermentation recorded. Sixteen microbial genera correlated with volatile flavor substances and Weissella, Lactobacillus, Pseudomonas, Rhodotorul, and Kwoniella had significant correlation with ethyl esters and higher alcohols. Micro-organisms thus influence flavor development during corn yellow wine fermentation.
    MeSH term(s) Wine/analysis ; Fermentation ; Zea mays ; Volatile Organic Compounds/analysis ; Volatile Organic Compounds/chemistry ; Microbiota ; Alcohols
    Chemical Substances Volatile Organic Compounds ; Alcohols
    Language English
    Publishing date 2023-11-13
    Publishing country United States
    Document type Journal Article
    ZDB-ID 165657-0
    ISSN 1520-6033 ; 8756-7938
    ISSN (online) 1520-6033
    ISSN 8756-7938
    DOI 10.1002/btpr.3408
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Restoration method of original occlusal vertical distance in edentulous jaw

    GUO Jianhua / LI Ying

    口腔疾病防治, Vol 28, Iss 7, Pp 472-

    2020  Volume 476

    Abstract: The loss of jaw position relationship will seriously affect the face and masticatory function of patients, and accurate restoration of vertical dimension of occlusion (OVD) is the key to occlusal reconstruction in edentulous patients. There are many ... ...

    Abstract The loss of jaw position relationship will seriously affect the face and masticatory function of patients, and accurate restoration of vertical dimension of occlusion (OVD) is the key to occlusal reconstruction in edentulous patients. There are many methods to measure OVD in edentulous patients. In this paper, the working principle, scope of application, advantages and disadvantages, measurement methods and operation points of OVD recording method are reviewed in order to provide some reference for clinical treatment. The results show that the pre- extraction recording method is more objective and accurate, but the diagnosis model before extraction is required to accurately reflect the patients′ original OVD; the rest and stop jaw reference method is easily affected by subjective factors, and the edentulous patients with unstable jaw relationship are forbidden; the swallowing method is more subjective, especially suitable for patients with emotional tension and poor coordination; The facial landmark measurement method is more objective, but it is also affected by some subjective measurement factors. The patients with maxillofacial malformation are forbidden; the subjectivity of speech method is strong, and the accuracy of measurement results is closely related to the clinical experience of doctors, and the patients with aphasia and deafness are forbidden. X-ray cephalometric method and finger measurement method have strong objectivity. They are new measurement methods in recent years and have a bright future. Among them, finger measurement method is especially suitable for patients with maxillofacial deformity or postoperative deformity of tumor.
    Keywords complete denture ; edentulous jaw ; vertical jaw position relationship ; vertical distance of occlusion ; occlusion reconstruction ; vertical jaw position relationship recording method ; rest and stop jaw position reference method ; swallowing method ; working principle ; facial sign measurement method ; voice method ; application scope ; x-ray cephalometry ; finger measurement method ; Medicine ; R
    Subject code 616
    Language Chinese
    Publishing date 2020-07-01T00:00:00Z
    Publisher Editorial Department of Journal of Prevention and Treatment for Stomatological Diseases
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Disinfection spreads antimicrobial resistance.

    Lu, Ji / Guo, Jianhua

    Science (New York, N.Y.)

    2021  Volume 371, Issue 6528, Page(s) 474

    MeSH term(s) Anti-Infective Agents, Local ; COVID-19/prevention & control ; Disinfection ; Drug Resistance, Microbial ; Hand Sanitizers ; Humans ; Pandemics
    Chemical Substances Anti-Infective Agents, Local ; Hand Sanitizers
    Language English
    Publishing date 2021-02-26
    Publishing country United States
    Document type Letter ; Research Support, Non-U.S. Gov't
    ZDB-ID 128410-1
    ISSN 1095-9203 ; 0036-8075
    ISSN (online) 1095-9203
    ISSN 0036-8075
    DOI 10.1126/science.abg4380
    Database MEDical Literature Analysis and Retrieval System OnLINE

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