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1.
The distribution of alleles I, II and III of the P adhesin gene papG among Escherichia coli isolated from urinary tract infections in humans, dogs and cats was studied by PCR. Allele I was present in 6% and 5% of the human and cat isolates. Allele II as such was present in 30% and 22%, or in association with allele III in 12% and 2% of the human and canine isolates, respectively. Allele III was present in 33% of the human strains and predominated largely over allele II in E. coli isolates from cystitis of animal origin (72% in dog and 95% in cat strains). The three different classes of the PapG adhesin have been suggested to play a role in host specificity, for example human versus canine specificity. Recent studies, however, showed papG III positive human and dog cystitis isolates to be largely indistinguishable. We found the Class II allele in animal isolates and detected for the first time in Europe the Class I allele in a different genetic background than the J96-like clonal group. Our findings show that uropathogenic E. coli isolates from different species can have the same papG alleles and thus may have zoonotic potential.  相似文献   

2.
Abstract Expression of globoside-specific pilus adhesin of Escherichia coli is the virulence factor most commonly associated with pyelonephritis. In the clinical isolate J96 (O4:K6:H5) expression of globoside binding pili require the proteins encoded by the papE, papF , and papG genes in the pap gene cluster. Probes derived from these genes were used in dot blot hybridization analysis of E. coli urinary tract isolates obtained from patients with significant bacteriuria. Fecal E. coli isolates from healthy individuals were also analyzed. The probe encompassing the papF and papF J96 genes hybridized to all urinary tract infectious (UTI) isolates expressing globoside-specific adhesin, whereas papG J96 only hybridized to the strain from which the fragment was cloned. In contrast, a papG -specific probe from the O:6 strain IA2 hybridized to all but one of the UTI isolates that expressed the adhesin. In both materials, but especially among the fecal isolates, strains were found that hybridized to the probes but did not express the adhesin. The data shows that papEF -specific DNA can be used for the diagnosis of potentially pyelonephritic E. coli .  相似文献   

3.
F P Lindberg  B Lund    S Normark 《The EMBO journal》1984,3(5):1167-1173
Most pyelonephritic Escherichia coli strains bind to digalactoside-containing glycolipids on uroepithelial cells. Purified Pap pili (pili associated with pyelonephritis) show the same binding specificity. A non-polar mutation early in the papA pilin gene abolishes formation of Pap pili but does not affect the degree of digalactoside-specific hemagglutination. Three novel pap genes, papE , papF and papG are defined in this report. The papF and papG gene products are both required for digalactoside-specific agglutination by whole bacteria cells as well as for agglutination by pilus preparations. Pili prepared from a papE mutant have lost their binding ability although whole cells from this mutant retain it, implying an adhesin anchoring role for the papE gene product. A mutant with lesions both in the papA and the papE genes does not mediate digalactoside-specific agglutination. The implications of this finding for pilus biogenesis are discussed.  相似文献   

4.
Over a 21-month period, three Beagle dogs and one mixed-breed dog at our facility developed fatal pneumonia. The four dogs, all purpose bred, came from three vendors and had received the standard canine vaccines prior to shipment. In each instance, the affected dog had been shipped to our facility within the past 10 days. Three cases presented as a peracute clinical syndrome, and all had gross and microscopic findings consistent with hemorrhagic pneumonia. Escherichia coli was isolated from the lungs of all four dogs. Results of testing of lung tissue for canine parainfluenza virus and canine adenovirus were negative. Escherichia coli was also isolated from blood of three of the four dogs. Serotyping of the E. coli isolates indicated that two were serotype 06 and two were 04. Isolates from all four dogs were positive for the virulence factors alpha hemolysin and cytotoxic necrotizing factor 1 and for the adhesin factor class-III papG allele. These traits place the isolates in the class of extraintestinal pathogenic E. coli, which is being increasingly implicated as a cause of extraintestinal infections in animals and humans and may represent a zoonotic risk to humans working with research dogs.  相似文献   

5.
Uropathogenic Escherichia coli frequently express globoside-specific adhesins, shown to mediate binding to uroepithelial cells. For one gene cluster pap, it recently has been demonstrated that globoside binding is not dependent on expression of the pilus subunit gene papA. Instead, two other pap genes papF and papG are specifically required for globoside binding (F. P. Lindberg et al., EMBO J. 3:1167-1173, 1984). By restriction enzyme mapping, DNA hybridization, DNA sequencing, and protein expression in minicells, we show that three gene clusters encoding globoside binding have a very similar structure and gene organization, although they were cloned from different E. coli isolates. Major differences between the adhesin clones were restricted to the central part of the pilin gene (papA) and to one of the two adhesin gene (papG). The three functional units required for biogenesis of globoside-binding pili, i.e., pilin synthesis, pilin export, and pilin assembly, as well as expression of adhesion function, were all trans complementable among the gene clusters.  相似文献   

6.
Genome editing can introduce designed mutations into a target genomic site. Recent research has revealed that it can also induce various unintended events such as structural variations, small indels, and substitutions at, and in some cases, away from the target site. These rearrangements may result in confounding phenotypes in biomedical research samples and cause a concern in clinical or agricultural applications. However, current genotyping methods do not allow a comprehensive analysis of diverse mutations for phasing and mosaic variant detection. Here, we developed a genotyping method with an on-target site analysis software named Determine Allele mutations and Judge Intended genotype by Nanopore sequencer (DAJIN) that can automatically identify and classify both intended and unintended diverse mutations, including point mutations, deletions, inversions, and cis double knock-in at single-nucleotide resolution. Our approach with DAJIN can handle approximately 100 samples under different editing conditions in a single run. With its high versatility, scalability, and convenience, DAJIN-assisted multiplex genotyping may become a new standard for validating genome editing outcomes.

Genome editing can introduce designed mutations into a target genomic site, but also into unintended off-target sites. DAJIN, a novel nanopore sequencing data analysis tool, identifies and quantifies allele numbers and their mutation patterns, reporting consensus sequences and visualizing mutations in alleles at single-nucleotide resolution.  相似文献   

7.
A G Klann  R A Hull  S I Hull 《Gene》1992,119(1):95-100
We report the sequence of the papE, papF and papG genes from the O75:K5 uropathogenic P pili variant, Pap-3. Comparison of the deduced amino acid sequences with those of other P pili variants reveals regions of complete homology, as well as regions of variation. Analysis of the variations in the hydrophilic domains of these proteins will help elucidate the residues which determine binding specificity.  相似文献   

8.
筛查转基因作物非预期效应遇到的最大难题是难以鉴别其非预期效应和自然变异.从转基因作物非预期效应与自然变异的发生机制、食用安全风险和遗传特性的比较分析阐述两者在发生机制及遗传特性方面的差异和特征,为设计减少自然变异干扰的非预期效应筛查模式和方案提供重要启示.  相似文献   

9.
The problem of unintended effects caused by genetic modification of plants is analysed. Factors that can provoke the unintended effects in genetically engineered plants, their consequences and possibility of the avoiding of unintended effects with use of current methods of genetic modification are discussed. Modern methodological approaches applied to analyse the unintended effects during the safety assessment of transgenic plants, in particular methods of molecular profiling with different "-omic"-technologies are described.  相似文献   

10.

Background

Unintended pregnancy has been a major reproductive health challenge in resource poor settings including Ethiopia. It has adverse consequences to the mother, child and the health sector’s resources. Understanding the extent of unintended pregnancy and the factors associated is crucial to devise evidence based interventions. The analysis was aimed at assessing the unintended pregnancy prevalence rate among pregnant women and the factors predisposing to unintended pregnancy.

Methods

This secondary data analysis was done on women’s dataset from the 2011 Ethiopian Demographic and Health Survey (DHS). A total of 1267 pregnant women were included in the analysis. Multiple logistic regression analysis was performed using SPSS software to identify the factors associated with unintended pregnancy. Odds Ratio with 95% confidence interval (95% CI) was computed to assess the association of different factors with unintended pregnancy.

Results

The overall prevalence of unintended pregnancy was found to be 24%: those who wanted it at a later time and not at all accounted for 17.1% and 6.9%, respectively. The unintended pregnancy rate ranged from 1.5% in Afar Regional State to 39.8% in Oromiya Regional State. Women who knew the timing of ovulation had a 45% reduced chance of unintended pregnancy (OR (95% CI): 0.55 (0.35, 0.85)). Ever use of family planning, presence of five or more born children, and two or more births in the past five years were associated with unintended pregnancy (OR (95% CI): 1.79 (1.31, 2.45), 2.36 (1.01, 5.49) and 2.00 (1.12, 3.58), respectively).

Conclusions

A significant proportion of the current pregnancies were found to be unintended with significant variations among the different regions. Women already burdened with higher fertility were suffering from unintended pregnancy. Family planning programs need to concentrate on the highly affected regions and target women with higher fertility to reduce the level of unintended pregnancy at national level.  相似文献   

11.
Type 1 fimbriae of Escherichia coli mediate mannose-specific adhesion to host epithelial surfaces and consist of a major, antigenically variable pilin subunit, FimA, and a minor, structurally conserved adhesive subunit, FimH, located on the fimbrial tip. We have analysed the variability of fimA and fimH in strains of vaginal and other origin that belong to one of the most prominent clonal groups of extraintestinal pathogenic E. coli, comprised of O1:K1-, O2:K1- and O18:K1-based serotypes. Multiple locus sequence typing (MLST) of this group revealed that the strains have identical (at all but one nucleotide position) eight housekeeping loci around the genome and belong to the ST95 complex defined by the publicly available E. coli MLST database. Multiple highly diverse fimA alleles have been introduced into the ST95 clonal complex via horizontal transfer, at a frequency comparable to that of genes defining the major O- and H-antigens. However, no further significant FimA diversification has occurred via point mutation after the transfers. In contrast, while fimH alleles also move horizontally (along with the fimA loci), they acquire point amino acid replacements at a higher rate than either housekeeping genes or fimA. These FimH mutations enhance binding to monomannose receptors and bacterial tropism for human vaginal epithelium. A similar pattern of rapid within-clonal structural evolution of the adhesive, but not pilin, subunit is also seen, respectively, in papG and papA alleles of the di-galactose-specific P-fimbriae. Thus, while structurally diverse pilin subunits of E. coli fimbriae are under selective pressure for frequent horizontal transfer between clones, the adhesive subunits of extraintestinal E. coli are under strong positive selection (Dn/Ds > 1 for fimH and papG) for functionally adaptive amino acid replacements.  相似文献   

12.
This study aims to understand the level of contraceptive knowledge and attitudes towards contraception, and then to explore the association between the contraceptive behavior and unintended pregnancy in unmarried female university students in China. A cross-sectional study was conducted of university students in 49 universities across 7 cities in China from September 2007 to January 2008. We distributed 74,800 questionnaires, of which 69,842 were returned. In this paper, the data from 35,383 unmarried female university students were analyzed. The prevalence of sexual intercourse in unmarried female university students was 10.2%. The prevalence of unintended pregnancy in those sexually active female university students, was 31.8%. Among students with pregnancy, 53.5% experienced two or more pregnancies. 28.3% of the students with sexual intercourse reported that they always adopted contraceptive methods, and of those 82.9% chose to use male condoms. The majority (83.9%) of students with unintended pregnancy chose to terminate the latest pregnancy by surgical abortion or medical abortion. The contraceptive knowledge level of students who experienced unintended pregnancy was lower than those who did not. In China, about one third of unmarried female students with sexual intercourse experience unintended pregnancy. A variety of contraceptive methods are adopted, but the frequency of contraceptive use is low. Most of unmarried female students who experienced unintended pregnancy would choose to terminate the pregnancy with surgical or medical abortion. University students, especially the ones who have experienced unintended pregnancy, lack contraceptive and reproductive health knowledge.  相似文献   

13.
The aim of this study was to convert existing faba bean (Vicia faba L.) single nucleotide polymorphism (SNP) markers from cleaved amplification polymorphic sequences and SNaPshot® formats, which are expensive and time-consuming, to the more convenient KBiosciences competitive allele‐specific PCR (KASP) assay format. Out of 80 assays designed, 75 were validated, though a core set of 67 of the most robust markers is recommended for further use. The 67 best KASP SNP assays were used across two generations of single seed descent to detect unintended outcrossing and to track and quantify loss of heterozygosity, a capability that will significantly increase the efficiency and performance of pure line production and maintenance. This same set of assays was also used to examine genetic relationships between the 67 members of the partly inbred panel, and should prove useful for line identification and diversity studies in the future.  相似文献   

14.
15.
16.
The problem of unintended effects, which may be caused by genetic modification of plants, is analyzed. The factors that provoke the occurrence of unintended effects in genetically engineered plants, the consequences caused by the influence of these factors, and the possibility to minimize such effects by the use of improved methods of genetic engineering are discussed. Modern methodological approaches that can be applied to the analysis of unintended effects considered as a stage of safety assessment of transgenic plants, especially the methods of molecular profiling with the use of different “-omic” technologies, are described.  相似文献   

17.
18.
BACKGROUND: We aimed to investigate the risk factors associated with unintended pregnancies as well as the association between unintended pregnancies and potential teratogenic exposures. METHODS: A cross-sectional survey was performed among women attending the Maternity School of the Samsung Cheil Hospital and Women's Health Care Center in Seoul, Korea. Demographic data, obstetric history, socioeconomic status, intention to become pregnant, and exposure to potential teratogens were obtained. RESULTS: A total of 1354 women with median age of 29 years and median gestational age of 29 weeks were included. Of these, an educational level above high school was 74.2%, primigravida was 77.3% and unintended pregnancy was 48%. In the logistic regression analysis, women younger than 24 years of age had a relative risk (RR) of 2.5 (95% confidence interval [CI], 1.3-4.7) of having an unintended pregnancy and women with lower household monthly income level had a RR of 1.3 (95% CI, 1.0-1.6). Women with unintended pregnancies had an RR of 1.9 (95% CI, 1.5-2.5), 3.0 (95% CI, 2.0-4.5), 1.5 (95% CI, 1.0-2.3), 2.9 (95% CI, 1.1-7.2), and 2.0 (95% CI, 1.62.4) of being exposed to alcohol, medications, cigarette smoking, X-rays, or to any of these, respectively, during the first trimester of pregnancy. CONCLUSIONS: Unintended pregnancies are more likely to occur among young women with a lower household monthly income level. Prenatal counseling should be especially recommended for women with unintended pregnancies in order to evaluate whether they have been exposed to potential teratogenic agents.  相似文献   

19.
Few studies have examined the impact of unintended pregnancy on women in developing countries. This paper examines the impact of unintended pregnancy on Indonesian women's psychological well-being. It is hypothesized that experiencing unintended pregnancy is associated with lower psychological well-being and that use of family planning and small family size are associated with higher levels of psychological well-being. Data are drawn from a 1996 survey of 796 women aged 15-49 from two Indonesian provinces, Lampung and South Sumatra. This article focuses on the 71% of women (n=562) who answered all 41 survey items related to psychological well-being. In cluster analysis, women grouped into three clusters, differentiated by their scores on four scales of well-being established through factor analysis (general negative feelings, satisfaction with relationships, satisfaction with economic/family/personal conditions, and negative feelings regarding domestic issues). Women in cluster 3 were characterized mainly by their high level of psychological well-being. Women in cluster 1 had the lowest level of well-being, and women in cluster 2 were in the middle. Multinomial logistic regression was used to assess jointly the effect of unintended pregnancy, contraceptive use, number of children and other factors on a woman's level of psychological well-being. Unintended pregnancy was associated with lower levels of psychological well-being and contraceptive use was associated with higher levels of psychological well-being, while number of children was not associated with level of well-being. Women who had experienced an unintended pregnancy were less likely to be in the high psychosocial well-being cluster versus both the medium and low clusters. In addition, women using contraception were more likely to be classified in the high than in the low or medium well-being clusters.  相似文献   

20.

Objective

To investigate the relationship of our interdisciplinary screening process on post-operative unintended hospitalizations and quality of life.

Background

There are currently no standardized criteria for selection of appropriate Deep Brain Stimulation candidates and little hard data exists to support the use of any singular method.

Methods

An Essential Tremor cohort was selected from our institutional Deep Brain Stimulation database. The interdisciplinary model utilized seven specialties who pre-operatively screened all potential Deep Brain Stimulation candidates. Concerns for surgery raised by each specialty were documented and classified as none, minor, or major. Charts were reviewed to identify unintended hospitalizations and quality of life measurements at 1 year post-surgery.

Results

Eighty-six percent (44/51) of the potential screened candidates were approved for Deep Brain Stimulation. Eight (18%) patients had an unintended hospitalization during the follow-up period. Patients with minor or major concerns raised by any specialty service had significantly more unintended hospitalizations when compared to patients without concerns (75% vs. 25%, p < 0.005). The rate of hospitalization revealed a direct relationship to the “level of concern”; ranging from 100% if major concerns, 42% if minor concerns, and 7% if no concerns raised, p = 0.001. Quality of life scores significantly worsened in patients with unintended hospitalizations at 6 (p = 0.046) and 12 months (p = 0.027) when compared to baseline scores. No significant differences in tremor scores between unintended and non-unintended hospitalizations were observed.

Conclusions

The number and level of concerns raised during interdisciplinary Deep Brain Stimulation screenings were significantly related to unintended hospitalizations and to a reduced quality of life. The interdisciplinary evaluation may help to stratify risk for these complications. However, data should be interpreted with caution due to the limitations of our study. Further prospective comparative and larger studies are required to confirm our results.  相似文献   

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