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51.
Alessandro Antonelli Mario Rotondi Poupak Fallahi Paola Romagnani Silvia Martina Ferrari Ele Ferrannini Mario Serio 《Journal of interferon & cytokine research》2005,25(9):547-552
Circulating levels of cytokines are deeply influenced by aging, and few data about serum chemokines are available. The aim of this study was to evaluate the influence of aging on circulating CXCL10. One hundred forty healthy subjects (70 males and 70 females), 10-79 years of age, underwent fasting plasma glucose, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglyceride, and CXCL8 serum assay. Thyroid hormone testing for thyroid-stimulating hormone (TSH), antithyroglobulin (AbTg), and antithyroperoxidase (AbTPO) autoantibodies and thyroid ultrasonography were performed in all subjects to exclude the presence of clinical or subclinical thyroid disease. Serum CXCL10 levels were assayed in all subjects and found to be increased in 14 of 70 females (20%) and in 4 of 70 males (5.7%) (p = 0.01). In a multiple linear regression model including age, body mass index (BMI), systolic and diastolic blood pressure, glycemia, total cholesterol, HDL, LDL, triglycerides, TSH, AbTPO, AbTg, and CXCL8, only age was significantly related to CXCL10 [C.R. 1.30 (0.28-2.33), p = 0.001]. No relationship was present between CXCL8 serum levels and age, suggesting a specificity of CXCL10 elevation as a function of age. Results of this study, performed in healthy subjects on an age gradient, demonstrate an increase in serum CXCL10 with advancing age overall in females, supporting the hypothesis of enhanced Th1 immune responses in aging. 相似文献
52.
Phenotypic and genotypic analyses of enterohemorrhagic Escherichia coli O145 strains from patients in Germany 总被引:5,自引:0,他引:5
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Sonntag AK Prager R Bielaszewska M Zhang W Fruth A Tschäpe H Karch H 《Journal of clinical microbiology》2004,42(3):954-962
Enterohemorrhagic Escherichia coli (EHEC) strains of serogroup O145 are emerging as causes of diarrhea and the hemolytic-uremic syndrome. However, there have been few genetic analyses of this EHEC group. We investigated the serotypes, virulence genes, plasmid profiles, pulsed-field gel electrophoresis (PFGE) patterns, and genetic variability of the fliC and eae genes in 120 EHEC O145 strains isolated from cases of hemolytic-uremic syndrome (n = 24) or diarrhea (n = 96) in Germany between 1996 and 2002. Three isolates belonged to serotype O145:H28, one to serotype O145:H25, and 116 were nonmotile (O145:H(-)). One hundred fourteen of the nonmotile strains shared fliC restriction fragment length polymorphism (RFLP) patterns identical to that of the O145:H28 strains. The remaining two nonmotile strains displayed a fliC-RFLP pattern identical to that of the O145:H25 strain. Each of the 117 strains with the fliC-RFLP(H28) pattern harbored eae gamma, whereas the three strains with the fliC-RFLP(H25) pattern possessed eae beta. Five different stx genotypes, six combinations of plasmid-encoded putative virulence genes, 29 plasmid profiles, and 47 PFGE types were identified. Strains within some of the PFGE types could be further subtyped by means of distinct plasmid profiles. These data demonstrate that the EHEC O145 serogroup is comprised of two different serotypes that possess distinct eae types. The heterogeneity of EHEC O145 strains at the chromosomal and plasmid level, in particular the high diversity in PFGE patterns, provides a basis for molecular subtyping of these pathogens. 相似文献
53.
Comparison of a highly automated 5-h susceptibility testing system, the Cobas-Bact, with two reference methods: Kirby-Bauer disk diffusion and broth microdilution. 总被引:2,自引:6,他引:2
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The results of susceptibility tests performed with the Cobas-Bact system were compared with those of the Kirby-Bauer disk diffusion and the broth microdilution methods. The evaluation included tests with 24 antibiotics against 250 isolates of the family Enterobacteriaceae and 13 antibiotics against 100 gram-positive cocci. Complete agreements between the Cobas-Bact and Kirby-Bauer methods were 82.8 and 84.5% for gram-positive cocci and gram-negative bacilli, respectively. Agreements between the Cobas-Bact and broth microdilution methods were 76.7% for gram-positive cocci and 84.8% for gram-negative bacilli. Complete agreements between the Kirby-Bauer and broth microdilution methods were 87.0% for gram-positive cocci and 92.2% for gram-negative bacilli. Despite generally satisfactory results with most organism-antibiotic combinations tested, additional modifications of the Cobas-Bact system are required to reduce the number of major and very major discrepancies, as well as to permit testing of Pseudomonas spp. and other gram-negative nonfermentative bacilli. 相似文献
54.
Robert H Friedman Sandhya Wahi-Gururaj Joel Alpert Howard Bauchner Larry Culpepper Timothy Heeren Allen Singer 《Academic medicine》2004,79(11):1095-1102
PURPOSE: To understand the views of U.S. medical school deans about their primary care faculties. METHOD: In 2000, the authors mailed a questionnaire containing 43 multipart items to deans of 130 U.S. allopathic medical schools. The questionnaire assessed the deans' attitudes about and evaluation of primary care at their school and their school's efforts to strengthen it. Deans were asked to compare family medicine, general internal medicine, and general pediatrics with nonprimary care clinical departments at their schools. RESULTS: Of the 83 (64%) deans who responded, 82% reported their school had departments or divisions of family medicine, general internal medicine, and general pediatrics. Deans rated general internal medicine and general pediatrics higher than nonprimary care faculty on clinical expertise and productivity (p < .001) and family medicine equivalent to nonprimary care faculty. Deans rated all three primary care faculties superior to nonprimary care faculty for teaching skills (p < .001) and programs (p < .05), but lower than nonprimary care disciplines for research productivity (p < .01) and revenues (p < .001). They rated family medicine and general pediatrics lower for research skills (p < .001), but 73% of deans stated research was equally important for primary care and nonprimary care departments. Deans considered overall financial resources to be equivalent for primary care and nonprimary care departments, but 77% of deans felt primary care departments or divisions needed financial support from the medical school to survive. Most deans attempted to strengthen primary care by changing the curriculum to promote primary care and by providing financial support. CONCLUSIONS: Deans ranked primary care faculty high on clinical and teaching measures. Although they considered research to be an important activity for primary care faculty, they evaluated it low relative to nonprimary care departments. 相似文献
55.
Expression and potential role of fibroblast growth factor 2 and its receptors in human embryonic stem cells 总被引:7,自引:0,他引:7
Dvorak P Dvorakova D Koskova S Vodinska M Najvirtova M Krekac D Hampl A 《Stem cells (Dayton, Ohio)》2005,23(8):1200-1211
Although the detection of several components of the fibroblast growth factor (FGF) signaling pathway in human embryonic stem cells (hESCs) has been reported, the functionality of that pathway and effects on cell fate decisions are yet to be established. In this study we characterized expression of FGF-2, the prototypic member of the FGF family, and its receptors (FGFRs) in undifferentiated and differentiating hESCs; subsequently, we analyzed the effects of FGF-2 on hESCs, acting as both exogenous and endogenous factors. We have determined that undifferentiated hESCs are abundant in several molecular-mass isoforms of FGF-2 and that expression pattern of these isoforms remains unchanged under conditions that induce hESC differentiation. Significantly, FGF-2 is released by hESCs into the medium, suggesting an autocrine activity. Expression of FGFRs in undifferentiated hESCs follows a specific pattern, with FGFR1 being the most abundant species and other receptors showing lower expression in the following order: FGFR1 --> FGFR3 --> FGFR4 --> FGFR2. Initiation of differentiation is accompanied by profound changes in FGFR expression, particularly the upregulation of FGFR1. When hESCs are exposed to exogenous FGF-2, extracellular signal-regulated kinases are phosphorylated and thereby activated. However, the presence or absence of exogenous FGF-2 does not significantly affect the proliferation of hESCs. Instead, increased concentration of exogenous FGF-2 leads to reduced outgrowth of hESC colonies with time in culture. Finally, the inhibitor of FGFRs, SU5402, was used to ascertain whether FGF-2 that is released by hESCs exerts its activities via autocrine pathways. Strikingly, the resultant inhibition of FGFR suppresses activation of downstream protein kinases and causes rapid cell differentiation, suggesting an involvement of autocrine FGF signals in the maintenance of proliferating hESCs in the undifferentiated state. In conclusion from our data, we propose that this endogenous FGF signaling pathway can be implicated in self-renewal or differentiation of hESCs. 相似文献
56.
Kuca K Cabal J Kassa J Jun D Hrabinová M 《Acta medica (Hradec Králové) / Universitas Carolina, Facultas Medica Hradec Králové》2005,48(2):81-86
(1) The efficacy of the oxime HL?7 and currently used oximes (pralidoxime, obidoxime, HI-6) to reactivate acetylcholinesterase inhibited by various nerve agents (sarin, tabun, cyclosarin, VX) was tested by in vitro methods. (2) Both H oximes (HL?-7, HI-6) were found to be more efficacious reactivators of sarin and VX-inhibited acetylcholinesterase than pralidoxime and obidoxime. On the other hand, their potency to reactivate tabun-inhibited acetylcholinesterase is very low and does not reach the reactivating efficacy of obidoxime. In the case of cyclosarin, the oxime HI-6 was only found to be able to sufficiently reactivate cyclosarin-inhibited acetylcholinesterase in vitro. (3) Thus, the oxime HL?-7 does not seem to be more efficacious reactivator of nerve agent-inhibited acetylcholinesterase than HI-6 according to in vitro evaluation of their reactivation potency and, therefore, it is not more suitable to be introduced for antidotal treatment of nerve agent-exposed people than HI-6. 相似文献
57.
58.
59.
Martina C. Cornel Anthonie J. van Essen Leo P. ten Kate 《American journal of medical genetics. Part A》1992,42(3):387-392
After the birth of a child with a congenital anomaly, parents have many questions about cause, prognosis, and recurrence risk. An important means of transmitting such information is referral to a genetic clinic. We were interested in knowing what determines whether or not parents are referred for genetic counseling. Data from the local registration of congenital anomalies in the northeastern Netherlands (birth years 1981–1986; 1,217 children/fetuses) and data of the local genetic clinic were compared. The parents of 204 cases (16.8%) had been referred for genetic counseling. Of the couples referred, 76% were referred within one year after birth, usually by a pediatrician (48%). Parents of children with a single anomaly, recognized syndrome, or multiple anomalies not recognized as a syndrome were referred in 5%, 43%, and 26% of cases, respectively. Parents of liveborn children who died were referred in 38% of cases, parents of liveborn/still-alive and stillborn children in 13% and 22%, respectively. Previous affected sibs and absence of previous livebirths increased the likelihood of referral. 相似文献
60.
Long-term elevations of dietary sodium produce parallel increases in the renal excretion of urodilatin and sodium 总被引:1,自引:0,他引:1
Martina Heer Christian Drummer Friedhelm Baisch Rupert Gerzer 《Pflügers Archiv : European journal of physiology》1993,425(5-6):390-394
The effects of dietary sodium intake on the renal excretion of urodilatin and of sodium were examined in six healthy male subjects. The 24-day study period was divided into three phases of 8 days each. Subjects Ingested 2.8 mequiv sodium (kg body weight)–1 day–1 during the first phase, 5.6 mequiv (kg body weight)–1 day–1 during the second phase, and 8.4 mequiv (kg body weight)–1 day–1 during the third phase. The excretion of both sodium (P<0.002) and urodilatin (P<0.006) increased in response to the increasing dietary sodium, while urine flow did not change. Urinary urodilatin excretion correlated closely with renal sodium excretion (P<0.001). Serum aldosterone levels (P<0.01) as well as serum renin levels (P<0.05) significantly decreased with increasing sodium intake. Plasma [Arg]vasopressin levels increased significantly (P<0.05). Plasma atrial natriuretic factor and cGMP levels as well as urinary cGMP excretion rates were unaltered by the changes in sodium intake. We conclude from these results that the renal natriuretic peptide, urodilatin, but not the main cardiac member of the natriuretic peptide family may be involved in the regulation of day-to-day sodium balance. 相似文献