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991.
Expression and characterization of the eaeA gene product of Escherichia coli serotype O157:H7. 总被引:7,自引:6,他引:1 下载免费PDF全文
M Louie J C de Azavedo M Y Handelsman C G Clark B Ally M Dytoc P Sherman J Brunton 《Infection and immunity》1993,61(10):4085-4092
In enteropathogenic Escherichia coli, the eaeA gene produces a 94-kDa outer membrane protein called intimin which has been shown to be necessary but not sufficient to produce the attaching-and-effacing lesion. The purpose of this study was to characterize the intimin specified by the eaeA allele of the enterohemorrhagic E. coli (EHEC) serotype O157:H7 strain CL8 and to determine its role in adherence. The carboxyl-terminal 266 amino acids of the CL8 intimin were expressed as a protein fusion with glutathione S-transferase, which was used to raise antiserum in rabbits. The antiserum reacted in Western immunoblots with a 97-kDa outer membrane protein of EHEC strains of serogroups O5, O26, O111, and O157 and enteropathogenic E. coli strains of serogroups O55 and O127. Surface labelling of CL8 with 125I showed that intimin was surface exposed. An eaeA insertional inactivation mutant of CL8 was produced and was designated CL8-KO1. Total adherence of CL8-KO1 to HEp-2 cells was not significantly different from that of CL8, but CL8-KO1 gave a negative result in the fluorescent actin staining test. The eaeA gene expressed alone in E. coli HB101 also gave a negative fluorescent actin staining test result. The eaeA gene of CL8 was able to complement the eaeA deletion mutation in CVD206. We conclude that the product of the EHEC eaeA gene is a 97-kDa surface-exposed protein and propose that it be designated intiminO157. Sherman et al. described a 94-kDa outer membrane protein which played an important role in adherence of E. coli O157:H7 (Infect. Immun. 59:890-899, 1991). Western immunoblotting and indirect fluorescent antibody studies showed that the protein described by Sherman et al. is not intimin. 相似文献
992.
Dermatitis in bulb growers 总被引:2,自引:0,他引:2
Derk P. Bruynzeel Edith M. de Boer Elly J. Brouwer Frederik A. de Wolff Peter de Haan 《Contact dermatitis》1993,29(1):11-15
A damaged skin forms a health hazard in flower-bulb growers as it enables higher permeation rates For pesticides than normal skin. Therefore, an investigation was performed into the skin condition of 103 bulb growers and 49 controls. Contact dermatitis of the hands was of the same order (11 and 10%) in both groups. However, minor signs of dermatitis were seen more often in bulb growers (30 versus 8%, p <0.05). Most growers had contact with narcissus sap during the investigation. This irritant sap, as well as many other skin contacts with irritants such as hyacinth dust and pesticides, seemed to be responsible for many skin complaints. Contact serialization was suspected in 19 growers and 3 controls. Patch tests showed that contact sensitization existed to pesticides in probably 10, and to flower-bulb extracts in 4 growers. Reactions to propachlor were not regarded as very reliable as the test concentration seemed to be marginally irritant. There were only a few allergic reactions to narcissus (3) and tulip (2) and none to hyacinth. This investigation showed that minor irritant contact dermatitis was frequent in bulb growers, and indicated that contact sensitization to pesticides and bulbs seemed to be a less frequent but important cause of dermatitis. 相似文献
993.
de Boer A; Schroder C; Reddingius R; Willems H; Monnens L 《Nephrology, dialysis, transplantation》1998,13(9):2348-2350
Background: The passage of proteins across the
glomerular filtration barrier is mainly determined by the size of the
protein. In nephrotic syndrome (NS) the glomerular permselectivity is
affected, causing proteinuria. Some authors suggest the existence of a
generalized basement membrane defect. The permeability characteristics of
the peritoneal basement membrane in children with NS are not known.
Methods: The transperitoneal transport of proteins
with a different molecular weight ({beta}2-microglobulin MW 11 800 D,
albumin MW 69 000 D, IgG MW 160 000 D, and &agr;2-macroglobulin MW 820
000 D) was studied in a study group (group A) consisting of six stable
nephrotic children (three with glomerulosclerosis and three with congenital
nephrotic syndrome, one of them with mesangial sclerosis) and compared to a
control group (group B) consisting of eight stable children on peritoneal
dialysis. After a dwell of 6 h with Dianeal 1.36% dialysate and serum
samples were collected. For each patient the dialysate to plasma (D/P)
ratio of the four proteins were calculated. The D/P ratios of the nephrotic
patients in group A were compared to the D/P ratios of the patients in the
control group B. Data were expressed as mean ±SD.
Results: The values for the D/P ratios (in percentage)
of {beta}2-microglobulin, albumin, IgG and &agr;2-macroglobulin in
group A were 19.6±9.9, 2.7±1.7, 1.6±0.9,
and 0.5±0.4, compared to 24.9±10.2,
4.0±2.3, 2.2±1.2, and 0.7±0.3 in the
control group B. The ratios were plotted against MW on a double logarithmic
scale. In all patients a linear relationship between molecular weight and
D/P ratio of the proteins was obtained. The D/P ratios of the study group
did no differ significantly from the control group.
Conclusion: We conclude that the size selectivity of
the capillary permeability is not affected in the peritoneal membrane in
children with NS due to glomerulosclerosis and congenital nephrotic
syndrome. 相似文献
994.
Randomised trial comparing the upright and supine positions for the second stage of labour 总被引:2,自引:1,他引:1
P. R. de Jong Senior Specialist R. B. Johanson Senior Lecturer P. Baxen Chief Professional Nurse V. D. Adrians Senior Professional Nurse S. van der Westhuisen Lecturer P. W. Jones Professor 《BJOG : an international journal of obstetrics and gynaecology》1997,104(5):567-571
Objective To assess the maternal and neonatal effects of upright compared with recumbent positions during delivery, in terms of defined outcome variables.
Design A randomised controlled trial.
Setting St Monica's Nursing Home, a midwife based maternity unit in Cape Town, South Africa.
Participants Five hundred and seventeen women of low obstetrical risk assigned to deliver at the nursing home.
Results The trial showed that women who adopted the upright posture for delivery experienced less pain, perineal trauma and fewer episiotomies than those who delivered in the supine position.
Conclusion The data suggest that in women of low obstetrical risk, choice of posture during delivery may be encouraged. 相似文献
Design A randomised controlled trial.
Setting St Monica's Nursing Home, a midwife based maternity unit in Cape Town, South Africa.
Participants Five hundred and seventeen women of low obstetrical risk assigned to deliver at the nursing home.
Results The trial showed that women who adopted the upright posture for delivery experienced less pain, perineal trauma and fewer episiotomies than those who delivered in the supine position.
Conclusion The data suggest that in women of low obstetrical risk, choice of posture during delivery may be encouraged. 相似文献
995.
Endoscopic Sphincterotomy and Biliary Drainage in Patients with Cholangitis Due to Common Bile Duct Stones 总被引:13,自引:0,他引:13
996.
Summary We report two cases of Creutzfeld-Jakob disease with clusters of giant collagen fibers. To our knowledge, these abnormally large collagen fibers have never been described in patients with degenerative diseases of the central nervous system. The significance of the formation of such plaque-like large collagen fibers has as yet not been elucidated. It is felt that these represent a product of the degenerative process.Presented in part at the 68th Annual Meeting of the American Association of Neuropathologists, St. Louis, Missouri, June 18–21, 1992 相似文献
997.
Introns and gene evolution 总被引:5,自引:0,他引:5
Sandro J. de Souza Manyuan Long & Walter Gilbert 《Genes to cells : devoted to molecular & cellular mechanisms》1996,1(6):493-505
In one scenario of gene evolution, exon shuffling has a fundamental role in increasing gene diversity. As DNA sequences accumulate in the databases, the picture of the intron/exon structures of genes becomes more and more clear. We discuss in this review some features of this picture that suggest that introns have been present since the early stages of evolution, and that exon shuffling was a fundamental process in the construction of ancient as well as modern genes. 相似文献
998.
A validity study of the Brazilian version of the 15-item Short Psychiatric Evaluation Schedule (SPES), included in the mental health assessment of Older Americans Resources and Services (OARS), designed to detect psychiatric disorders in the elderly, against the "caseness" criterion suggested by Cooper and Schwarz was carried out with a community sample, as part of a survey to study health and living conditions of the elderly in a large urban center of a developing country, S?o Paulo, Brazil. The screening questionnaire was completed by 292 subjects, and 91 were selected for the psychiatric interview. The validity coefficients were as follows: sensitivity 61%, specificity 89%, positive predictive value 66%, negative predictive value 87% and misclassification rate 18%. A discriminant analysis using a stepwise procedure was then applied to select the best item discriminators of the screening questionnaire. The best set of discrimination comprised six items leading to the following validity coefficients: sensitivity 82%, specificity 77%, positive predictive value 58%, negative predictive value 92% and misclassification rate 21%. The possible factors related to false positive and false negative responses on the screening are discussed. 相似文献
999.
This report describes the laparoscopic features of two patients with serosal eosinophilic gastroenteritis. In one case only hyperemia of the peritoneal serosa was found. In the other the laparoscopic picture resembled peritoneal carcinomatosis. We show that laparoscopy and peritoneal biopsy may permit diagnosis of the disease without the need for laparotomy. 相似文献
1000.
A Giorgio P Amoroso G Francica G de Stefano P Fico G Lettieri L Tarantino L Finelli F Fiorentino P Pierri 《Gastrointestinal radiology》1988,13(4):336-340
To clarify the therapeutic role of echo-guided percutaneous puncture (EPP) in management of amebic liver abscess, 20 patients (24 abscesses) received metronidazole plus EPP. Fluid was aspirated through Chiba needles under real-time sonographic guidance so as to reduce cavity size to less than 3 cm. Not more than two EPPs were necessary in the majority of cases and no complication followed the procedure. This scheme resulted in a shortening of time of both hospitalization (less than or equal to 20 days) and liver lesion healing as assessed by ultrasound (less than or equal to 4 months). It is concluded that EPP is a valuable and safe therapeutic tool for hepatic amebic abscess. 相似文献