Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
8
result(s) for
"Hu, Shuangfang"
Sort by:
Rapid detection of human origin colistin-resistance genes mcr-1, mcr-3, mcr-8, mcr-10 in clinical fecal samples
2021
Plasmid-mediated colistin-resistance genes have been reported in human origin clinical samples worldwide which raises its threats to human infections. Notably,
mcr-1
,
mcr-3
,
mcr-8
, and
mcr-10
have been reported isolated directly from clinical samples which creates more seriously threaten to human health than other
mcr
gene types. A multiplex polymerase chain reaction (Multi-PCR) protocol was developed to detect and genotype mobile colistin-resistance genes (
mcr-1
,
mcr-3
,
mcr-8
,
mcr-10
) in
Enterobacteria
for clinical laboratory purposes. We first designed four pairs of new primers for the amplification of
mcr
-1,
mcr
-3,
mcr
-8, and
mcr
-10 gene respectively to achieve stepwise separation of amplicons between 216 and 241 bp, and complete this Multi-PCR system with the assistance of another pair of universal primer. Among which the forward primers for
mcr-8
and
mcr-10
amplicons were identical. The protocol was validated by testing 11 clinical isolates of
Escherichia coli
and 3 clinical isolates of
Klebsiella
from human origin, each well characterized and prospectively validated. The Multi-PCR assay showed full concordance with whole-genome sequence data and displayed higher sensitivity and 100% specificity. The assay could detect all variants of the various
mcr
alleles described. The Multi-PCR assay successfully genotyped of
mcr
alleles described in one test.
Journal Article
Multiplex PCR for detection of MCR genes in clinical fecal samples
2021
Plasmid-mediated colistin-resistance genes have been reported worldwide in recent years. A multiplex polymerase chain reaction (Multi-PCR) protocol was developed to detect transferable colistinresistance genes ( mcr-1 to mcr-6 ) in Enterobacteria for clinical laboratory purposes.The authors first designed six new primer pairs to amplify mcr-1 to mcr-6 gene products to achieve stepwise separation of amplicons between 87 to 216 bp,then divided these primers into two subgroups with the assistance of a pair of universal primers for the detection of currently described mcr genes and their variants in Enterobacteria . The protocol was validated by testing 29 clinical isolates of Escherichia coli of human origin, each well characterised and prospectively validated. The Multi-PCR assay showed full concordance with whole-genome sequence data and displayed higher sensitivity and 100% specificity. The assay could detect all variants of the various mcr alleles described. It was able to detect mcr-3 and mcr-4 as singletons or in combination. This type of test is critical for the epidemiological surveillance of plasmid-encoded resistance in limited resources conditions, and this method allows rapid identification of mcr -positive bacteria and overcomes the challenges of phenotypic detection of colistin resistance.
Journal Article
Dietary Factors of blaNDM Carriage in Health Community Population: A Cross-Sectional Study
by
Wang, Yang
,
Xiang, Qiumei
,
Shen, Jianzhong
in
Antibiotics
,
Antimicrobial agents
,
Blood pressure
2021
Aim: There is an ongoing debate as to what extent antimicrobial resistance (AMR) can be transmitted from dietary to humans via the consumption of food products. We investigated this association between dietary and global spreading carbapenem-resistant gene blaNDM Methods: We did a cross-sectional study to assess the risk factors for carrier of blaNDM in health community. Healthy adults were recruited from the residents attending Community Healthcare Service in Shenzhen City (Guangdong Province, China), through 1February 2018 to 31December 2019, and 718 pre-participants were included in this study. Questionnaire were obtained and the qualitative food frequency questionnaire (Q-FFQ) were used to assess dietary intake. qPCR was applied to confirm the carrier of blaNDM in participants’fecal samples. Multivariable logistic regression was used to estimate the odds ratio (OR) and 95% confidence interval (95% CI) of each outcome according to each dietary factor before and after prosperity score matching (PSM). Results: we showed that a high intake of coarse grain (OR 1.003; 95% CI 1.001–1.005, p < 0.01) and root and tuber crops (OR 1.003; 95% CI 1.001–1.004, p < 0.05) were independent risk factor for blaNDM carrier in health communities, suggesting a possible transfer of AMRbetweendietary andhumans. Surprisingly, we also showed an association between a higher intake of poultry as a protective, which may be explained by the beneficial effects on the gut microbiota. Conclusion: Dietary factors such as intake of coarse grain, root and tuber crops and poultry were associated with blaNDM carrier in health communities. The influence of dietary factorson blaNDM carrier in the present study provides insights for the tangible dietary advice with guidelines to the routine of people with the risk of blaNDM carrier. This demonstrates the role of dietary intake in the prevention of blaNDM carrier, since prevention is the best way to control modifiable risk factors. A lower carrier rate of blaNDM is helpful to reduce the possibility of transmission and pathogenicity. Further studies on food, microbiota and antimicrobial resistance are necessary to confirm this possible association and unravel underlying mechanisms.
Journal Article
Dietary Factors of blasub.NDM Carriage in Health Community Population: A Cross-Sectional Study
by
Wang, Yang
,
Xiang, Qiumei
,
Shen, Jianzhong
in
Backup software
,
Drug resistance in microorganisms
,
Food
2021
Aim: There is an ongoing debate as to what extent antimicrobial resistance (AMR) can be transmitted from dietary to humans via the consumption of food products. We investigated this association between dietary and global spreading carbapenem-resistant gene bla [sub.NDM] Methods: We did a cross-sectional study to assess the risk factors for carrier of bla [sub.NDM] in health community. Healthy adults were recruited from the residents attending Community Healthcare Service in Shenzhen City (Guangdong Province, China), through 1February 2018 to 31December 2019, and 718 pre-participants were included in this study. Questionnaire were obtained and the qualitative food frequency questionnaire (Q-FFQ) were used to assess dietary intake. qPCR was applied to confirm the carrier of bla [sub.NDM] in participants’fecal samples. Multivariable logistic regression was used to estimate the odds ratio (OR) and 95% confidence interval (95% CI) of each outcome according to each dietary factor before and after prosperity score matching (PSM). Results: we showed that a high intake of coarse grain (OR 1.003; 95% CI 1.001–1.005, p < 0.01) and root and tuber crops (OR 1.003; 95% CI 1.001–1.004, p < 0.05) were independent risk factor for bla [sub.NDM] carrier in health communities, suggesting a possible transfer of AMRbetweendietary andhumans. Surprisingly, we also showed an association between a higher intake of poultry as a protective, which may be explained by the beneficial effects on the gut microbiota. Conclusion: Dietary factors such as intake of coarse grain, root and tuber crops and poultry were associated with bla [sub.NDM] carrier in health communities. The influence of dietary factorson bla [sub.NDM] carrier in the present study provides insights for the tangible dietary advice with guidelines to the routine of people with the risk of bla [sub.NDM] carrier. This demonstrates the role of dietary intake in the prevention of bla [sub.NDM] carrier, since prevention is the best way to control modifiable risk factors. A lower carrier rate of bla [sub.NDM] is helpful to reduce the possibility of transmission and pathogenicity. Further studies on food, microbiota and antimicrobial resistance are necessary to confirm this possible association and unravel underlying mechanisms.
Journal Article
An Integrated Imaging Study of the Pore Structure of the Cobourg Limestone—A Potential Nuclear Waste Host Rock in Canada
2021
With the development of imaging technology, tools to quantitatively describe pore structure, morphology, and connectivity have been widely applied on low permeable rocks; however, it is still questionable to what extent this information can be used to predict permeability. Applicability and comparability of different techniques are discussed here for the Middle Ordovician Cobourg limestone (Canada), a rock dominated by calcite grains of variable sizes (µm–cm) and heterogeneously distributed quartz, dolomite, pyrite, and meshy clay minerals. Absolute porosities determined by helium pycnometry (HP) in literature are approximately 1.6% (±0.9%), and gas permeabilities range from 10−20 to 10−19 m2. Porosities obtained from BIB-SEM are much smaller compared to those from HP (16–69% of HP). Pores found in clays are smaller, slit-shaped, and more densely spaced when compared to those in calcite minerals. Connectivity between pores could not be resolved with 3D micro-CT or FIB-SEM reconstructions, which have a resolution limit of 8 µm and 10 nm, respectively. However, assuming the pores to be connected, laboratory-derived permeability data could be fitted using a simple capillary bundle model, including information about the visible pore size distributions obtained from BIB-SEM images and a tortuosity range of 8 to 15.
Journal Article
Lacustrine shale oil resource potential of Es3L Sub-Member of Bonan Sag, Bohai Bay Basin, Eastern China
by
Lu, Shuangfang
,
Xiao, Dianshi
,
Zhang, Linye
in
Biogeosciences
,
Earth and Environmental Science
,
Earth Sciences
2017
Following shale gas, shale oil has become another highlight in unconventional hydrocarbon exploration and development. A large amount of shale oil has been produced from a host of marine shale in North America in recent years. In China, lacustrine shale, as the main source rock of conventional oil and gas, should also have abundant oil retained in place. In this study, geochemical and geologic characteristics of lacustrine shale from Es
3
L
sub-member in Bonan sag were characterized by using total organic carbon (TOC), Rock-Eval pyrolysis, X-ray diffraction, and Δlog R method. The results show that the Es
3
L
sub-member shale have TOC contents ranging from 0.5 wt.% to 9.3 wt.%, with an average of 2.9 wt.%. The organic matter is predominantly Type I kerogen, with minor amounts of Type II1 kerogen. The temperature of maximum yield of pyrolysate (
T
max
) values ranges from 424 to 447 °C, with an average of 440 °C, and vitrinite reflectance (Ro%) ranges from 0.7% to 0.9%, indicating most of shales are thermally mature. The dominant minerals of Es
3
L
shale in Bonan sag are carbonates (including calcite and dolomite), averaging 51.82 wt.%, and the second minerals are clay (mostly are montmorillonite-illite-mixed layer and illite) and quartz, averaging about 18 wt.%. Finally, its shale oil resources were evaluated by using the volumetric method, and the evaluation result shows that the shale oil resource is up to 5.94 billion tons, and mostly Class I resource. Therefore, the exploration of the lacustrine shale oil of Es
3
L
in Bonan sag should be strengthened.
Journal Article
Lacustrine Shale Oil Resource Potential of EsL 3Sub-Member of Bonan Sag, Bohai Bay Basin, Eastern China
2017
Following shale gas, shale oil has become another highlight in unconventional hydrocar-bon exploration and development. A large amount of shale oil has been produced from a host of marine shale in North America in recent years. In China, lacustrine shale, as the main source rock of conven-tional oil and gas, should also have abundant oil retained in place. In this study, geochemical and geo-logic characteristics of lacustrine shale from EsL 3sub-member in Bonan sag were characterized by using total organic carbon (TOC), Rock-Eval pyrolysis, X-ray diffraction, and?logR method. The results show that the EsL 3sub-member shale have TOC contents ranging from 0.5 wt.% to 9.3 wt.%, with an average of 2.9 wt.%. The organic matter is predominantly Type I kerogen, with minor amounts of Type Ⅱ1 kerogen. The temperature of maximum yield of pyrolysate (Tmax) values ranges from 424 to 447 °C, with an average of 440 °C, and vitrinite reflectance (Ro%) ranges from 0.7% to 0.9%, indicating most of shales are thermally mature. The dominant minerals of EsL 3shale in Bonan sag are carbonates (in-cluding calcite and dolomite), averaging 51.82 wt.%, and the second minerals are clay (mostly are montmorillonite-illite-mixed layer and illite) and quartz, averaging about 18 wt.%. Finally, its shale oil resources were evaluated by using the volumetric method, and the evaluation result shows that the shale oil resource is up to 5.94 billion tons, and mostly Class Ⅰ resource. Therefore, the exploration of the lacustrine shale oil of EsL 3in Bonan sag should be strengthened.
Journal Article