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41.
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   
42.
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   
43.
(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   
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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   
47.
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   
48.
Rho GTPases have been shown recently to be important for cell polarity and motility of the trunk mesoderm during gastrulation in Xenopus embryos. This work demonstrated that Rho and Rac have both distinct and overlapping roles in regulating cell shape, and the dynamic properties, polarity, and type of protrusive activity of these cells. Overexpression of activated or inhibitory versions of these GTPases also disrupts development of the head in Xenopus embryos. In this study, we have undertaken a detailed analysis of Rho and Rac function in migrating anterior mesendoderm cells. Scanning electron micrographs of these cells in situ revealed that their normal shingle arrangement is disrupted and both the cells and their lamellipodia are disoriented. Anterior mesendoderm explants plated on their natural blastocoel roof matrix, however, still migrated towards the animal pole, although the tendency to move in this direction is reduced compared to controls. Analysis of a number of parameters in time-lapse recordings of dissociated cells indicated that Rho and Rac also have both distinct and overlapping roles in the motility of the prospective head mesoderm; however, their effects differ to those previously seen in the trunk mesoderm. Both GTPases appear to modulate cell polarization, migration, and protrusive activity. Rho alone, however, regulates the retraction of the lagging edge of the cell. We propose that within the gastrulating Xenopus embryo, two types of mesoderm cells that undergo different motilities have distinct responses to Rho GTPases.  相似文献   
49.
Hepatic stellate cells (HSC) and liver myofibroblasts (MFB) are two cell populations most likely responsible for the synthesis of most connective tissue components in fibrotic liver. They differ in their origin and location, and possibly in patterns of gene expression. Normal and carbon tetrachloride-cirrhotic livers from rats were used to isolate HSC. Liver was perfused with pronase and collagenase solutions, followed by centrifugation of the cell suspension on a density gradient. HSC were quiescent 2 days after plating on plastic but they became activated after another 5 days in culture. When the culture was passaged 5 times, its character changed profoundly as HSC were replaced by MFB. Microarray analysis was used to determine gene expression in quiescent HSC, activated HSC and MFB. The expression of 49 genes coding for connective tissue proteins, proteoglycans, metalloproteinases and their inhibitors, growth factors and cellular markers was determined. The pattern of gene expression changed during HSC activation and there were distinct differences between HSC and MFB. Little difference between normal cells and cells isolated from cirrhotic liver was found.  相似文献   
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