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31.
Symptomatic peripheral arterial disease: the value of a validated questionnaire and a clinical decision rule
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Bianca LW Bendermacher Joep AW Teijink Edith M Willigendael Marie-Louise Bartelink Harry R Büller Ron JG Peters Jelis Boiten Machteld Langenberg Martin H Prins 《The British journal of general practice》2006,56(533):932-937
BACKGROUND: If a validated questionnaire, when applied to patients reporting with symptoms of intermittent claudication, could adequately discriminate between those with and without peripheral arterial disease, GPs could avoid the diagnostic measurement of the ankle brachial index. AIM: To investigate the Edinburgh Claudication Questionnaire (ECQ) in general practice and to develop a clinical decision rule based on risk factors to enable GPs to easily assess the likelihood of peripheral arterial disease. DESIGN OF STUDY: An observational study. SETTING: General practice in The Netherlands. METHOD: This observational study included patients of > or =55 years visiting their GP for symptoms suggestive of intermittent claudication or with one risk factor. The ECQ and the ankle brachial index were performed. The prevalence of peripheral arterial disease, defined as an ankle brachial index <0.9, was related to risk factors using logistic regression analyses, on which a clinical decision rule was developed and related to the presence of peripheral arterial disease. RESULTS: Of the 4790 included patients visiting their GP with symptoms suggestive of intermittent claudication, 4527 were eligible for analyses. The prevalence of peripheral arterial disease in this group was 48.3%. The sensitivity of the ECQ was only 56.2%. The prevalence of peripheral arterial disease in a clinical decision rule that included age, male sex, smoking, hypertension, hypercholesterolemia, and a positive ECQ, increased from 14% in the lowest to 76% in the highest category. CONCLUSION: This study indicates that the ECQ alone has an inadequate diagnostic value in detecting patients with peripheral arterial disease. The ankle brachial index should be performed to diagnose peripheral arterial disease in patients with complaints suggestive of intermittent claudication, although our clinical decision rule could help to differentiate between extremely high and lower prevalence of peripheral arterial disease. 相似文献
32.
Oncornaviruses produced by murine leukemia cells in culture. 总被引:19,自引:0,他引:19
Leukemia cells from mice of the AKR and C58 strains produced leukemia viruses (MuLV) in culture that failed to induce syncytia in the XC plaque assay (XC?), were poorly infectious for mouse embryo fibroblasts, and yielded low levels of infectious progeny upon the establishment of infection. In host range analysis the majority of these viruses were N-ecotropic, although one leukemia cell line also produced xenotropic MuLV. Viral isolates from five different leukemia cell lines were oncogenic upon inoculation into newborn AKR mice. In contrast, viruses that occurred in high titer in the tissues and sera of normal AKR mice were not oncogenic in vivo and in culture they efficiently induced (with N-ecotropism) syncytia in the XC plaque assay (XC+). These findings demonstrate that the transforming agent for spontaneous leukemogenesis differs in biological properties from the endogenous MuLV that is commonly observed in mice of high leukemic strains. 相似文献
33.
Inhibition of human polymorphonuclear leukocyte function by components of human colostrum and mature milk
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To compare the effect of human colostrum (days 1 to 3 postpartum) and mature milk (days 170 ± 24 postpartum) on the function of polymorphonuclear leukocytes (PMNL), Ficoll-Hypaque-separated PMNL from the blood of 60 healthy volunteers were incubated with whole colostrum, colostral lipid, and colostral aqueous phase from 30 mothers, or with mature whole milk and its separated components from 30 mothers, and tested for resting and zymosan-stimulated oxidative metabolism, functional activity, and the presence of Fc receptors. Stimulated oxygen consumption, quantitative nitroblue tetrazolium dye reduction, [1-14C]glucose utilization, and Fc receptors were significantly (P < 0.05 to P < 0.001) less in PMNL exposed to whole human colostrum or colostral lipid than in non-lipid-exposed cells or cells exposed to the aqueous phase of colostrum. In contrast, PMNL exposed to whole mature milk or to its lipid or aqueous phase caused no significant decrease in any of these parameters when compared to nonexposed cells. In assays of phagocytosis, colostral PMNL or blood PMNL exposed to colostral lipid had a significant (P < 0.001) decrease in their ability to ingest [methyl-3H]thymidine-labeled Staphylococcus aureus when compared to non-lipid-exposed PMNL. Blood PMNL exposed to lipid from mature milk had no decrease in ability to ingest S. aureus. Analysis of total lipid and total and individual fatty acid content revealed a uniform increase in all components in mature milk when compared to colostrum. Lipid or lipid-soluble material present in human colostrum but not mature milk causes inhibition of phagocytosis and respiratory burst-related activities of PMNL. 相似文献
34.
Mutational analysis of the SOX9 gene in campomelic dysplasia and autosomal sex reversal: lack of genotype/phenotype correlations 总被引:9,自引:1,他引:9
Meyer J; Sudbeck P; Held M; Wagner T; Schmitz ML; Bricarelli FD; Eggermont E; Friedrich U; Haas OA; Kobelt A; Leroy JG; Van Maldergem L; Michel E; Mitulla B; Pfeiffer RA; Schinzel A; Schmidt H; Scherer G 《Human molecular genetics》1997,6(1):91-98
It has previously been shown that, in the heterozygous state, mutations in
the SOX9 gene cause campomelic dysplasia (CD) and the often associated
autosomal XY sex reversal. In 12 CD patients, 10 novel mutations and one
recurrent mutation were characterized in one SOX9 allele each, and in one
case, no mutation was found. Four missense mutations are all located within
the high mobility group (HMG) domain. They either reduce or abolish the
DNA-binding ability of the mutant SOX9 proteins. Among the five nonsense
and three frameshift mutations identified, two leave the C-terminal
transactivation (TA) domain encompassing residues 402-509 of SOX9 partly or
almost completely intact. When tested in cell transfection experiments, the
recurrent nonsense mutation Y440X, found in two patients who survived for
four and more than 9 years, respectively, exhibits some residual
transactivation ability. In contrast, a frameshift mutation extending the
protein by 70 residues at codon 507, found in a patient who died shortly
after birth, showed no transactivation. This is apparently due to
instability of the mutant SOX9 protein as demonstrated by Western blotting.
Amino acid substitutions and nonsense mutations are found in patients with
and without XY sex reversal, indicating that sex reversal in CD is subject
to variable penetrance. Finally, none of 18 female patients with XY gonadal
dysgenesis (Swyer syndrome) showed an altered SOX9 banding pattern in SSCP
assays, providing evidence that SOX9 mutations do not usually result in XY
sex reversal without skeletal malformations.
相似文献
35.
Linda M. Gerber Joseph E. Schwartz Peter L. Schnall Thomas G. Pickering 《American journal of human biology》1995,7(2):173-182
The extent to which the relationship between body fat and blood pressure either differs by sex or explains sex differences in blood pressure is examined. Estimates of the relationship of blood pressure to several measures of adiposity in men and women were obtained from a systematic review of the literature and tests of whether these relationships differ by sex were performed. Analysis of covariance (controlling for age and race) was used for both casual and ambulatory blood pressure in the Cornell Worksite Blood Pressure Study (N = 276). In general, most adiposity measures were significantly related to casual and ambulatory blood pressure in men and women. Subscapular skinfold thickness and body mass index exhibited the strongest associations. The vast majority of adiposity/blood pressure associations were not significantly different for men and women. Finally, sex differences in adiposity did not account for much of the sex difference observed in blood pressure. © 1995 Wiley-Liss, Inc. 相似文献
36.
Immune haemolysis in chicken serum was examined using rabbit cells, sensitized with chicken antibody. Salt concentration was a major influence on complement activity: titres were greatly increased at ionic strengths which sustain negligible activity of human, rabbit, or guinea-pig complements. Sensitivity of the assay was also increased if standard Mg+ + was lowered to 7.5 × 10-4 M and Ca+ + increased to 6–9 × 10-4 M. Cobalt ion and Ba+ + facilitated complement activity; Ni+ + did not. Cobalt ion seemed to act as an Mg+ + substitute, and barium as a replacement for Ca+ +. The kinetics of haemolysis in this system resembled those of human complement: a rapid initial rate, followed by a slower one, but no levelling off at 4 hours.Natural antibody to rabbit cells may be excluded from the titration by absorption or by limiting Mg+ + in the buffer. The nature of this Mg+ + dependence is unknown. 相似文献
37.
Pickering Susan J.; Muggleton-Harris Audrey L. 《Human reproduction (Oxford, England)》1995,10(4):1021-1029
Human embryos have been biopsied at either the cleavage or theblastocyst stage of development. One to two blastomeres wereremoved from cleavage-stage embryos and 26 cells fromblastocysts. The biopsy specimens were subjected to gene amplificationby the polymerase chain reaction (PCR) and a comparison madeof amplification efficiencies of two unique target sequences,one located within the -globin gene and containing the sickle-celllocus and the other a polymorphic dinucleotide repeat. Whenthe cleavage-stage biopsy sample consisted of an intact blastomerewith a clearly discernible nucleus, an amplification efficiencyof 89% was achieved for each target locus. This was similarto that achieved with cleavage-stage biopsy samples consistingof two blastomeres or with blastocyst biopsy samples consistingof 23 trophectoderm cells. When biopsy samples consistedof four or more trophectoderm cells, both target loci were amplifiedin all samples tested. When the biopsy sample was heterozygousat the dinucleotide repeat locus and the biopsy consisted ofone or more intact cells with a clearly discernible nucleus,both alleles were amplified in >80% of biopsy samples. Whenfour or more trophectoderm cells were used for the PCR, bothalleles were amplified in all heterozygous samples. Target sequenceswere never amplified from biopsy samples which lysed prior totransfer into the reaction tube. Analysis of DNA fragments amplifiedfrom the dinucleotide repeat locus indicated that in most casesfaithful amplification of biopsy DNA template had taken place.However, in one case, fragments were identified which couldnot have resulted from the amplification of embryonic sequencesalone, indicating that contamination with extraneous DNA mayhave taken place. The significance of this finding for therapeuticpreimplantation genetic diagnosis is discussed. 相似文献
38.
Molecular characterization of invasive and noninvasive Campylobacter jejuni and Campylobacter coli isolates
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Carvalho AC Ruiz-Palacios GM Ramos-Cervantes P Cervantes LE Jiang X Pickering LK 《Journal of clinical microbiology》2001,39(4):1353-1359
Campylobacter jejuni is one of the most common causes of bacterial diarrhea worldwide and is the primary bacterial cause of food-borne illness. Adherence to and invasion of epithelial cells are the most important pathogenic mechanisms of Campylobacter diarrhea. Molecular characterization of invasive and noninvasive Campylobacter isolates from children with diarrhea and symptom-free children was performed by random amplified polymorphic DNA techniques (RAPD). A distinct RAPD profile with a DNA band of 1.6 kb was observed significantly more frequently among invasive (63%) than among noninvasive (16%) Campylobacter isolates (P = 0.000005). The 1.6-kb band was named the invasion-associated marker (IAM). Using specifically designed primers, a fragment of 518 bp of the iam locus was amplified in 85% of invasive and 20% of noninvasive strains (P = 0.0000000). Molecular typing with a PCR-restriction fragment length polymorphism assay which amplified the entire iam locus showed a HindIII restriction fragment polymorphism pattern associated mainly with invasive strains. Although cluster analysis of the RAPD fingerprinting showed genetic diversity among strains, two main clusters were identified. Cluster I comprised significantly more pathogenic and invasive isolates, while cluster II grouped the majority of nonpathogenic, noninvasive isolates. These data indicate that most of the invasive Campylobacter strains could be differentiated from noninvasive isolates by RAPD analysis and PCR using specific primers that amplify a fragment of the iam locus. 相似文献
39.
Comparative susceptibility of latin american and united states students to enteric pathogens. 总被引:20,自引:0,他引:20
H L DuPont J Olarte D G Evans L K Pickering E Galindo D J Evans 《The New England journal of medicine》1976,295(27):1520-1521
40.
A panel of nine monoclonal antibodies against the gp70 and p15(E) envelope proteins of MuLV were tested in parallel for their ability to bind to virus and neutralize infectivity. Although each of the antibodies bound to N-ecotropic MuLV, only antibody against the gp70f epitope neutralized infectivity. These results were interpreted as evidence for a specific site on the gp70 protein of ecotropic MuLV, in proximity of the gp70f epitope, which was responsible for the ecotropic-specific binding of virus to the surface of cells. 相似文献