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1.
Meike Lippelt Theresa Sanabria de Isele Manfred Kist 《Clinical microbiology and infection》1997,3(2):229-235
Objective: To carry out an epidemiologic evaluation of Salmonella enterica subsp. enterica serovar Enteritidis outbreaks in households and small communities by means of rRNA gene restriction pattern analysis (ribotyping).
Method: One hundred Enteritidis isolates dating from 1989 to 1994 which could be allocated epidemiologically to different sources or to small community outbreaks were investigated with ribotyping, a fingerprinting method in which bacterial DNA is hybridized with the biotin-labeled plasmid pKK 3535 containing a ribosomal RNA operon of Escherichia coli to determine the ribosomal RNA gene restriction patterns.
Results: Four different ribotyping patterns were found with the restriction endonuclease Sma I and nine with Sph I. Ribotypes of isolates which could be allocated epidemiologically to a common source usually corresponded. Almost 60% of the Enteritidis infections had the ribotyping pattern Sph I-A. In contrast, this pattern was not found in any of the five Enteritidis strains isolated in 1989. The suspicion that Enteritidis phage type 4 infections are caused by consumption of insufficiently heated eggs is supported by the fact that the ribotyping pattern Sph 1-A was found in isolates from eggs and from human specimens.
Conclusions: As patterns Sph I-A and Sma I-J appeared in 58% and 75% of the isolates, respectively, ribotyping cannot be used for the differentiation between various outbreaks with these two patterns. In cases where the Enteritidis strains showed less frequent patterns, ribotyping seems to be a practical tool for the identification of infection chains. In addition newly appearing ribotyping patterns can give information about the epidemiologic development of Enteritidis infection. 相似文献
Method: One hundred Enteritidis isolates dating from 1989 to 1994 which could be allocated epidemiologically to different sources or to small community outbreaks were investigated with ribotyping, a fingerprinting method in which bacterial DNA is hybridized with the biotin-labeled plasmid pKK 3535 containing a ribosomal RNA operon of Escherichia coli to determine the ribosomal RNA gene restriction patterns.
Results: Four different ribotyping patterns were found with the restriction endonuclease Sma I and nine with Sph I. Ribotypes of isolates which could be allocated epidemiologically to a common source usually corresponded. Almost 60% of the Enteritidis infections had the ribotyping pattern Sph I-A. In contrast, this pattern was not found in any of the five Enteritidis strains isolated in 1989. The suspicion that Enteritidis phage type 4 infections are caused by consumption of insufficiently heated eggs is supported by the fact that the ribotyping pattern Sph 1-A was found in isolates from eggs and from human specimens.
Conclusions: As patterns Sph I-A and Sma I-J appeared in 58% and 75% of the isolates, respectively, ribotyping cannot be used for the differentiation between various outbreaks with these two patterns. In cases where the Enteritidis strains showed less frequent patterns, ribotyping seems to be a practical tool for the identification of infection chains. In addition newly appearing ribotyping patterns can give information about the epidemiologic development of Enteritidis infection. 相似文献
2.
Mary ER O'Brien Janet Hardy Sylvia Tan Jackie Walling Brian Peters Sarah Hatty Eve Wiltshaw 《Cancer chemotherapy and pharmacology》1992,30(3):245-248
Summary A total of 16 patients with recurrent epithelial ovarian cancer were treated with sulofenur (LY 186641), a novel oral sulfonylurea. All subjects had received previous chemotherapy. Anaemia occurred in all 16 patients, 14 of whom required a blood transfusion, and 2/16 patients received methylene blue for breathlessness due to methaemaglobinaemia. Treatment was discontinued in 2/16 cases due to rising liver enzyme values, which reverted to normal on cessation of the drug. There was no nausea or alopecia. Only two minor responses were seen. Plasma drug levels were insufficient to result in antitumour activity as extrapolated from animal data. Further studies that attempt to increase the bioavailability and improve the therapeutic index are warranted. 相似文献
3.
Linkage of the MHC to familial multiple sclerosis suggests genetic heterogeneity. The Multiple Sclerosis Genetics Group 总被引:5,自引:0,他引:5
Haines JL; Terwedow HA; Burgess K; Pericak-Vance MA; Rimmler JB; Martin ER; Oksenberg JR; Lincoln R; Zhang DY; Banatao DR; Gatto N; Goodkin DE; Hauser SL 《Human molecular genetics》1998,7(8):1229-1234
Multiple sclerosis (MS) is a demyelinating autoimmune disease of the
central nervous system. While its etiology is not well understood, genetic
factors are clearly involved. Until recently, most genetic studies in MS
have been association studies using the case-control design testing
specific candidate genes and studying only sporadic cases. The only
consistently replicated finding has been an association with the HLA-DR2
allele within the major histocompatibility complex (MHC) on chromosome 6.
Using the genetic linkage design, however, evidence for and against linkage
of the MHC to MS has been found, fostering suggestions that sporadic and
familial MS have different etiologies. Most recently, two of four genomic
screens demonstrated linkage to the MHC, although specific allelic
associations were not tested. Here, a dataset of 98 multiplex families was
studied to test for an association to the HLA-DR2 allele in familial MS and
to determine if genetic linkage to the MHC was due solely to such an
association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta)
in the MHC demonstrated strong genetic linkage (parametric lod scores of
4.60, 2.20 and 1.24, respectively) and a specific association with the
HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results
by HLA-DR2 status showed that the linkage results were limited to families
segregating HLA-DR2 alleles. These results demonstrate that genetic linkage
to the MHC can be explained by the HLA-DR2 allelic association. They also
indicate that sporadic and familial MS share a common genetic
susceptibility. In addition, preliminary calculations suggest that the MHC
explains between 17 and 62% of the genetic etiology of MS. This
heterogeneity is also supported by the minority of families showing no
linkage or association with loci within the MHC.
相似文献
4.
5.
Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation 总被引:22,自引:1,他引:22
Marsh DJ; Coulon V; Lunetta KL; Rocca-Serra P; Dahia PL; Zheng Z; Liaw D; Caron S; Duboue B; Lin AY; Richardson AL; Bonnetblanc JM; Bressieux JM; Cabarrot-Moreau A; Chompret A; Demange L; Eeles RA; Yahanda AM; Fearon ER; Fricker JP; Gorlin RJ; Hodgson SV; Huson S; Lacombe D; Eng C 《Human molecular genetics》1998,7(3):507-515
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403
amino acid dual specificity phosphatase (protein tyrosine phosphatase;
PTPase), was shown recently to play a broad role in human malignancy.
Somatic PTEN deletions and mutations were observed in sporadic breast,
brain, prostate and kidney cancer cell lines and in several primary tumours
such as endometrial carcinomas, malignant melanoma and thyroid tumours. In
addition, PTEN was identified as the susceptibility gene for two hamartoma
syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or
Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD
families and seven BZS families was screened for germline PTEN mutations.
PTEN mutations were identified in 30 of 37 (81%) CD families, including
missense and nonsense point mutations, deletions, insertions, a
deletion/insertion and splice site mutations. These mutations were
scattered over the entire length of PTEN , with the exception of the first,
fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified
in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD
mutations identified in this exon. Seven of 30 (23%) were within the core
motif, the majority (five of seven) of which were missense mutations,
possibly pointing to the functional significance of this region. Germline
PTEN mutations were identified in four of seven (57%) BZS families studied.
Interestingly, none of these mutations was observed in the PTPase core
motif. It is also worthy of note that a single nonsense point mutation,
R233X, was observed in the germline DNA from two unrelated CD families and
one BZS family. Genotype-phenotype studies were not performed on this small
group of BZS families. However, genotype-phenotype analysis inthe group of
CD families revealed two possible associations worthy of follow-up in
independent analyses. The first was an association noted in the group of CD
families with breast disease. A correlation was observed between the
presence/absence of a PTEN mutation and the type of breast involvement
(unaffected versus benign versus malignant). Specifically and more
directly, an association was also observed between the presence of a PTEN
mutation and malignant breast disease. Secondly, there appeared to be an
interdependent association between mutations upstream and within the PTPase
core motif, the core motif containing the majority of missense mutations,
and the involvement of all major organ systems (central nervous system,
thyroid, breast, skin and gastrointestinal tract). However, these
observations would need to be confirmed by studying a larger number of CD
families.
相似文献
6.
Assessing the effect of visual and tactile distractors on the perception of auditory apparent motion
Sanabria D Soto-Faraco S Spence C 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,166(3-4):548-558
In this study we investigated the effect of the directional congruency of tactile, visual, or bimodal visuotactile apparent motion distractors on the perception of auditory apparent motion. Participants had to judge the direction in which an auditory apparent motion stream moved (left-to-right or right-to-left) while trying to ignore one of a range of distractor stimuli, including unimodal tactile or visual, bimodal visuotactile, and crossmodal (i.e., composed of one visual and one tactile stimulus) distractors. Significant crossmodal dynamic capture effects (i.e., better performance when the target and distractor stimuli moved in the same direction rather than in opposite directions) were demonstrated in all conditions. Bimodal distractors elicited more crossmodal dynamic capture than unimodal distractors, thus providing the first empirical demonstration of the effect of information presented simultaneously in two irrelevant sensory modalities on the perception of motion in a third (target) sensory modality. The results of a second experiment demonstrated that the capture effect reported in the crossmodal distractor condition was most probably attributable to the combined effect of the individual static distractors (i.e., to ventriloquism) rather than to any emergent property of crossmodal apparent motion. 相似文献
7.
Predicting infection in localized intraabdominal fluid collections: value of pH and pO2 measurements
Wong JK Mustard R Gray RR Sadler DJ Sanabria J Bohnen JM Schouten BD Doyle G Pugash RA 《Journal of vascular and interventional radiology : JVIR》1999,10(4):421-427
PURPOSE: To evaluate the use of pH, pO2, and the subjective opinion of the radiologist compared with bacterial culture in accurate diagnoses of bacterial infection in intraabdominal fluid collections. MATERIALS AND METHODS: Prospectively, 79 patients who were suspected of having an intraabdominal fluid collection underwent diagnostic fluid aspiration. The aspirate was cultured and measured for pH and pO2. A pH < or = 7.1 and a PO2 < or = 49 mm Hg were threshold values used to separate infected from sterile fluid collections. RESULTS: pH alone had a 92% sensitivity and 79% specificity, whereas PO2 alone had a 51% sensitivity and 79% specificity. pH or pO2 combined yielded a 92% sensitivity and 60% specificity. The radiologist's opinion produced a 83% sensitivity and 92% specificity. pH and the radiologist's opinion combined produced a 78% sensitivity and 96% specificity. pH or the radiologist's opinion combined had a 95% sensitivity and a 63% specificity. CONCLUSION: pH is the most sensitive indicator of infection and the radiologist's opinion is the most specific. We recommend proceeding to drainage if the radiologist believes the collection to be infected and performing pH analysis if not. If the pH < or = 7.04, proceed to drainage. If neither of the above criteria are met, drainage could be delayed, pending the results of culture. 相似文献
8.
目的:建立以高效液相色谱法测定小儿磨积片中橙皮苷含量的方法。方法:色谱柱为SpherisorbC18,流动相为甲醇-冰醋酸-水(25∶4∶71),检测波长为283nm,流速为2·0ml/min,柱温为50℃,灵敏度为0·16AUFS,进样量为20μl。结果:橙皮苷进样量在0·024μg~1·2μg范围内与峰面积积分值呈良好的线性关系(r=0·9999),平均回收率为99·1%(RSD=0·8%)。结论:本方法简便、快捷,灵敏度及准确度高,可为小儿磨积片质量控制提供依据。 相似文献
9.
10.
Vanessa Moñivas Palomero Alejandro Durante-Lopez Mario Torres Sanabria Javier Segovia Cubero Jesús González-Mirelis Jorge Vazquez Lopez-Ibor Sara M. Navarro Rico Isabel Krsnik Fernando Dominguez Alejandro Martinez Mingo Francisco J. Hernandez-Perez Gibanel Cavero Susana Mingo Santos 《Journal of the American Society of Echocardiography》2019,32(7):845-853.e1