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1.
A meta‐analysis of the association between Helicobacter pylori (H. pylori) infection and hyperemesis gravidarum
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Qin Xiang Ng Nandini Venkatanarayanan Michelle Lee Zhi Qing De Deyn Collin Yih Xian Ho Yin Mo Wee‐Song Yeo 《Helicobacter》2018,23(1)
Background
Hyperemesis gravidarum remains a common, distressing, and significant yet poorly understood disorder during pregnancy. The association between maternal Helicobacter pylori (H. pylori) infection and hyperemesis gravidarum has been increasingly recognized and investigated. This study thus aimed to provide an updated review and meta‐analysis of the topic.Methods
Using the search terms (H. pyloriOR Helicobacter ORHelicobacter pyloriOR infection) AND (pregnancy OR emesis OR hyperemesis gravidarum OR nausea OR vomiting), a preliminary search on the PubMed, Ovid, Web of Science, Google Scholar, and WanFang database yielded 372 papers published in English between January 1st, 1960 and June 1st, 2017.Results
A total of 38 cross‐sectional and case‐control studies, with a total of 10 289 patients were eligible for review. Meta‐analysis revealed a significant association between H. pylori infection and hyperemesis gravidarum during pregnancy, with a pooled odds ratio of 1.348 (95% CI: 1.156‐1.539, P < .001). Subgroup analysis found that serologic and stool antigen tests were comparable methods of detecting H. pylori as they yielded similar odds ratios.Limitations
Although the studies did not have high heterogeneity (I2 = 28%), publication bias was observed, and interstudy discrepancies in the diagnostic criteria adopted for hyperemesis gravidarum limit the reliability of findings. Also, 15 of the included studies were from the same country (Turkey), which could limit the generalizability of current findings. The prevalence of H. pylori infection varies throughout the world, and there may also be pathogenic differences as most strains of H. pylori in East Asia carry the cytotoxin‐associated gene A gene.Conclusion
H. pylori infection was associated with an increased likelihood of hyperemesis gravidarum during pregnancy. Given the high prevalence of H. pylori infections worldwide, detecting H. pylori infection and the eradication of maternal H. pylori infection could be part of maternal hyperemesis gravidarum management. Further confirmation with robust longitudinal studies and mechanistic investigations are needed. 相似文献2.
Aims
To test the hypothesis that Mycobacterium bovis can persist in the environment within protozoa.Methods and Results
In this study, we used a novel approach to detect internalized mycobacteria in environmental protozoa from badger latrines. Acid‐fast micro‐organisms were visualized in isolated amoebae, although we were unable to identify them to species level as no mycobacteria were grown from these samples nor was M. bovis detected by IS6110 PCR. Co‐incubation of Acanthamoeba castellanii with virulent M. bovis substantially reduced levels of bacilli, indicating that the amoebae have a negative effect on the persistence of M. bovis.Conclusions
The internalization of mycobacteria in protozoa might be a rare event under environmental conditions. The results suggest that amoebae might contribute to the inactivation of M. bovis rather than representing a potential environmental reservoir.Significance and Impact of the Study
Protozoa have been suggested to act as an environmental reservoir for M. bovis. The current study suggests that environmental amoebae play at most a minor role as potential reservoirs of M. bovis and that protozoa might inhibit persistence of M. bovis in the environment. 相似文献3.
M.J. Torres A. Hidalgo‐García E.J. Bedmar M.J. Delgado 《Journal of applied microbiology》2013,114(6):1772-1781
Aim
In this work, phenotypic analyses of a Ensifer meliloti fixN1 mutant under free‐living and symbiotic conditions have been carried out.Methods and Results
Ensifer meliloti fixN1 mutant showed a defect in growth as well as in TMPD‐dependent oxidase activity when cells were incubated under micro‐oxic conditions. Furthermore, haem c staining analyses of a fixN1 and a fixP1 mutant identified two membrane‐bound c‐type cytochromes of 27 and 32 kDa, present in microaerobically grown cells and in bacteroids, as the FixO and FixP components of the E. meliloti cbb3 oxidase. Under symbiotic conditions, fixN1 mutant showed a clear nitrogen fixation defect in alfalfa plants that were grown in an N‐free nutrient solution during 3 weeks. However, in plants grown for a longer period, fixNOQP1 copy was not indispensable for symbiotic nitrogen fixation.Conclusions
The copy 1 of the fixNOQP operon is involved in E. meliloti respiration and growth under micro‐oxic conditions as well as in the expression of the FixO and FixP components of the cbb3 oxidase present in free‐living microaerobic cultures and in bacteroids. This copy is important for nitrogen fixation during the early steps of the symbiosis.Significance and Impact of the Study
It is the first time that a functional analysis of the E. meliloti copy 1 of the fixNOQP operon is performed. In this work, the cytochromes c that constitute the cbb3 oxidase operating in free‐living micro‐oxic cultures and in bacteroids of E. meliloti have been identified. 相似文献4.
Andrew M Staroscik David W Hunnicutt Kate E Archibald David R Nelson 《BMC microbiology》2008,8(1):115
Background
Flavobacterium columnare is the causative agent of columnaris disease, a disease affecting many freshwater fish species. Methods for the genetic manipulation for some of the species within the Bacteroidetes, including members of the genus Flavobacterium, have been described, but these methods were not adapted to work with F. columnare. 相似文献5.
M. Ohnishi A.T. Okatani H. Esaki K. Harada T. Sawada M. Murakami K. Marumo Y. Kato R. Sato K. Shimura N. Hatanaka T. Takahashi 《Journal of applied microbiology》2013,115(1):282-289
Aims
To determine the herd prevalence of Enterobacteriaceae producing CTX‐M‐type extended‐spectrum β‐lactamases (ESBLs) among 381 dairy farms in Japan.Methods and Results
Between 2007 and 2009, we screened 897 faecal samples using BTB lactose agar plates containing cefotaxime (2 μg ml?1). Positive isolates were tested using ESBL confirmatory tests, PCR and sequencing for CTX‐M, AmpC, TEM and SHV. The incidence of Enterobacteriaceae producing CTX‐M‐15 (n = 7), CTX‐M‐2 (n = 12), CTX‐M‐14 (n = 3), CMY‐2 (n = 2) or CTX‐M‐15/2/14 and CMY‐2 (n = 4) in bovine faeces was 28/897 (3·1%) faecal samples. These genes had spread to Escherichia coli (n = 23) and three genera of Enterobacteriaceae (n = 5). Herd prevalence was found to be 20/381 (5·2%) dairy farms. The 23 E. coli isolates showed clonal diversity, as assessed by multilocus sequence typing and pulsed‐field gel electrophoresis. The pandemic E. coli strain ST131 producing CTX‐M‐15 or CTX‐M‐27 was not detected.Conclusions
Three clusters of CTX‐M (CTX‐M‐15, CTX‐M‐2, CTX‐M‐14) had spread among Japanese dairy farms.Significance and Impact of the Study
This is the first report on the prevalence of multidrug‐resistant CTX‐M‐15–producing E. coli among Japanese dairy farms. 相似文献6.
Background
Bacteria of the genus Bartonella are responsible for a large variety of human and animal diseases. Serological typing of Bartonella is a method that can be used for differentiation and identification of Bartonella subspecies. 相似文献7.
Para‐psychobiotic Lactobacillus gasseri CP2305 ameliorates stress‐related symptoms and sleep quality
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Aims
To confirm the stress‐relieving effects of heat‐inactivated, enteric‐colonizing Lactobacillus gasseri CP2305 (paraprobiotic CP2305) in medical students taking a cadaver dissection course.Methods and Results
Healthy students (21 males and 11 females) took paraprobiotic CP2305 daily for 5 weeks during a cadaver dissection course. The General Health Questionnaire and the Pittsburgh Sleep Quality Index were employed to assess stress‐related somatic symptoms and sleep quality respectively. The aggravation of stress‐associated somatic symptoms was observed in female students (P = 0·029). Sleep quality was improved in the paraprobiotic CP2305 group (P = 0·038), particularly in men (P = 0·004). Among men, paraprobiotic CP2305 shortened sleep latency (P = 0·035) and increased sleep duration (P = 0·048). Diarrhoea‐like symptoms were also effectively controlled with CP2305 (P = 0·005) in men. Thus, we observed sex‐related differences in the effects of paraprobiotic CP2305. In addition, CP2305 affected the growth of faecal Bacteroides vulgatus and Dorea longicatena, which are involved in intestinal inflammation.Conclusions
CP2305 is a potential paraprobiotic that regulates stress responses, and its beneficial effects may depend on specific cell component(s).Significance and Impact of the Study
This study characterizes the effects of a stress‐relieving para‐psychobiotic in humans. 相似文献8.
Bryan G. Valencia Mark B. Bush Angela L. Coe Elizabeth Orren William D. Gosling 《Journal of Biogeography》2018,45(5):1019-1030
Aim
To determine the palaeoecological influences of climate change and human land use on the spatial distribution patterns of Polylepis woodlands in the Andes.Location
Tropical Andes above 2,900 m between 2°S and 18°S of latitude.Methods
Pollen and charcoal data were gathered from 13 Andean lake sediment records and were rescaled by the maximum value in each site. The rescaled pollen data were used to estimate a mean abundance and coefficient of variation to show woodland expansions/contractions and woodland fragmentation over the last 20,000 years. The rescaled charcoal was displayed as a 200‐year moving median using 500‐year bins to infer the influence of fire on woodland dynamics at landscape scale. Pollen and charcoal were compared with speleothem, clastic flux and archaeological data to assess the influence of moisture balance, glacial activity and human impact on the spatial distribution of Polylepis woodlands.Results
Woodland expansion and fire were correlated with precipitation changes and glacier dynamics from c. 20 to 6 kcal bp (thousands of calibrated years before present). Charcoal abundances between 20 and 12 kcal bp were less common than from 12 kcal bp to modern. However, human‐induced fires were unlikely to be the main cause of a woodland decline centred at 11 kcal bp , as woodlands recovered from 10.5 to 9.5 kcal bp (about twofold increase). Charcoal peaks analogous to those that induced the woodland decline at 11 kcal bp were commonplace post‐9.5 kcal bp but did not trigger an equivalent woodland contraction. An increase in the coefficient of variation after c. 5.5 kcal bp suggests enhanced fragmentation and coincided with the shift from logistic to exponential growth of human populations. Over the last 1,000 years, Polylepis became hyper‐fragmented with over half of sites losing Polylepis from the record and with coefficients of variation paralleling those of glacial times.Main conclusions
Polylepis woodlands formed naturally patchy woodlands, rather than a continuous vegetation belt, prior to human occupation in the Andes. The main factors controlling pre‐human woodland dynamics were precipitation and landscape heterogeneity. Human activity led to hyper‐fragmentation during the last c. 1,000 years. 相似文献9.
Background
The dspA (hik33) gene, coding for a putative sensory histidine kinase, is conserved in plastids (ycf26) and cyanobacteria. It has been linked with a number of different stress responses in cyanobacteria. 相似文献10.
Background
The bioenergetics of Archaea with respect to the evolution of electron transfer systems is very interesting. In contrast to terminal oxidases, a canonical bc 1 complex has not yet been isolated from Archaea. In particular, c -type cytochromes have been reported only for a limited number of species. 相似文献11.
Background
Decapentaplegic (Dpp) is one of the best characterized morphogens, required for dorso-ventral patterning of the Drosophila embryo and for anterior-posterior (A/P) patterning of the wing imaginal disc. In the larval wing pouch, the Dpp target gene optomotor-blind (omb) is generally assumed to be expressed in a step function above a certain threshold of Dpp signaling activity. 相似文献12.
13.
Anna Pistocchi Germano Gaudenzi Silvia Carra Erica Bresciani Luca Del Giacco Franco Cotelli 《BMC developmental biology》2008,8(1):27
Background
Prox1, the vertebrate homolog of prospero in Drosophila melanogaster, is a divergent homeogene that regulates cell proliferation, fate determination and differentiation during vertebrate embryonic development. 相似文献14.
Background
Ligand endocytosis plays a critical role in regulating the activity of the Notch pathway. The Drosophila homolog of auxilin (dAux), a J-domain-containing protein best known for its role in the disassembly of clathrin coats from clathrin-coated vesicles, has recently been implicated in Notch signaling, although its exact mechanism remains poorly understood. 相似文献15.
Anna Giardina Rosa Alduina Elvira Gottardi Valentina Di Caro Roderich D Süssmuth Anna M Puglia 《Microbial cell factories》2010,9(1):44
Background
A bacterial artificial chromosomal library of Planobispora rosea, a genetically intractable actinomycete strain, was constructed using Escherichia coli - Streptomyces artificial chromosome (ESAC) and screened for the presence of genes known to be involved in the biosynthesis of antibiotics. 相似文献16.
17.
Background
Heme is typically a major iron source for bacteria, but little is known about how bacteria of the Leptospira genus, composed of both saprophytic and pathogenic species, access heme. 相似文献18.
M. Storari R. von Rohr I. Pertot C. Gessler G.A.L. Broggini 《Journal of applied microbiology》2013,114(4):1193-1200
Aims
To develop two assays based on the loop‐mediated isothermal amplification (LAMP) of DNA for the quick and specific identification of Aspergillus carbonarius and ochratoxigenic strains of the Aspergillus niger clade isolated from grapes.Methods and Results
Two sets of primers were designed based on the polyketide synthase genes involved or putatively involved in ochratoxin A (OTA) biosynthesis in A. carbonarius and A. niger clade. Hydroxynaphthol blue was used as indirect method to indicate DNA amplification. The limit of detection of both assays was comparable to that of a PCR reaction. Specificities of the reactions were tested using DNA from different black aspergilli isolated from grapes. The two LAMP assays were then used to identify A. carbonarius and ochratoxigenic A. niger and A. awamori grown in pure cultures without a prior DNA extraction.Conclusions
The two LAMP assays permitted to quickly and specifically identify DNA from OTA‐producing black aspergilli, as well as isolates grown in pure culture.Significance and Impact of the Study
Monitoring vineyards for the presence of OTA‐producing strains is part of the measures to minimize the occurrence of OTA in grape products. The two LAMP assays developed here could be potentially used to speed the screening process of vineyards for the presence of OTA‐producing black aspergilli. 相似文献19.
Background
The Mycoplasma hominis vaa gene encodes a highly variable, surface antigen involved in the adhesion to host cells. We have analysed the structure of the vaa locus to elucidate the genetic basis for variation of vaa. 相似文献20.
N. Nayan A.S.M. Sonnenberg W.H. Hendriks J.W. Cone 《Journal of applied microbiology》2018,125(2):468-479