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Mechanical function of intermediate filaments in arteries of different size examined using desmin deficient mice 总被引:2,自引:1,他引:1
Oskar Karlsson Wede Mia Löfgren Zhenlin Li† Denise Paulin† ers Arner 《The Journal of physiology》2002,540(3):941-949
Protein composition and mechanical function of intermediate filaments were examined in arteries of different sizes using desmin deficient mice (Des−/−) and their wild-type controls (Des+/+). Using SDS-PAGE gels and Western blots we found a gradient in desmin expression in the arterial tree; the desmin content increased from the elastic artery aorta, via the muscular mesenteric artery to the resistance-sized mesenteric microarteries ∼150 μm in diameter in Des+/+ mice. Mechanical experiments were performed on the aorta, the mesenteric artery and resistance-sized arteries using wire myographs. For aorta and mesenteric artery, no differences in passive or active circumference- stress relations were found between Des−/− and Des+/+ mice. In microarteries, both passive and active stress were lower in the Des−/− group. In conclusion, large elastic and muscular arteries contain a relatively low amount of desmin, and the desmin intermediate filaments do not seem to play a major role in the mechanical properties of these larger arterial vessels. In the microarteries, where expression of desmin is high, desmin plays a role in supporting both passive and active tension. 相似文献
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Juha-Matti Savola Michael Hill Mia Engstrom Hannele Merivuori Siegfried Wurster Steven G McGuire Susan H Fox Alan R Crossman Jonathan M Brotchie 《Movement disorders》2003,18(8):872-883
Previous studies in the MPTP-lesioned primate model of Parkinson's disease have demonstrated that alpha(2) adrenergic receptor antagonists such as idazoxan, rauwolscine, and yohimbine can alleviate L-dopa-induced dyskinesia and, in the case of idazoxan, enhance the duration of anti-parkinsonian action of L-dopa. Here we describe a novel alpha(2) antagonist, fipamezole (JP-1730), which has high affinity at human alpha(2A) (K(i), 9.2 nM), alpha(2B) (17 nM), and alpha(2C) (55 nM) receptors. In functional assays, the potent antagonist properties of JP-1730 were demonstrated by its ability to reduce adrenaline-induced (35)S-GTPgammaS binding with K(B) values of 8.4 nM, 16 nM, 4.7 nM at human alpha(2A), alpha(2B), and alpha(2C) receptors, respectively. Assessment of the ability of JP-1730 to bind to a range of 30 other binding sites showed that JP-1730 also had moderate affinity at histamine H1 and H3 receptors and the serotonin (5-HT) transporter (IC(50) 100 nM to 1 microM). In the MPTP-lesioned marmoset, JP-1730 (10 mg/kg) significantly reduced L-dopa-induced dyskinesia without compromising the anti-parkinsonian action of L-dopa. The duration of action of the combination of L-dopa and JP-1730 (10 mg/kg) was 66% greater than that of L-dopa alone. These data suggest that JP-1730 is a potent alpha(2) adrenergic receptor antagonist with potential as an anti-dyskinetic agent in the treatment of Parkinson's disease. 相似文献
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Information on the growth of contemporary Native American adolescents is limited. A few studies have shown that Native Americans have growth patterns that may differ from U.S. reference values. We describe basic anthropometric characteristics (height and weight) of Mohawk youth between the ages of 10.0 and 16.99 years from the Akwesasne Mohawk Nation. Body mass index (BMI) was calculated. Mean height of Akwesasne Mohawk youth approximates the 50th percentile of reference values as determined by the 2000 Center for Disease Control and Prevention (CDC) growth charts. At every age, weight means of males approximate or exceed the 90th percentile and all mean weights of females approximate the 85th percentile. Akwesasne males are significantly taller than females from age 14 on and significantly heavier at ages 14 and 16. All age-specific BMI means for males are at or above the 90th percentile and females' means are at or above the 85th. The potential for long-term health effects associated with being overweight has implications for the future health of young Native Americans. 相似文献
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Mia le Riche Annalise E Zemlin Rajiv T Erasmus M Razeen Davids 《Suid-Afrikaanse tydskrif vir geneeskunde》2007,97(10):968-970
BACKGROUND: Internationally, clinical guidelines recommend the use of creatinine-based equations to estimate glomerular filtration rate (GFR) for assessment and follow-up of kidney disease. The routine use of 24-hour creatinine clearances (CrCl) is no longer advocated. OBJECTIVES: To examine the indications for requesting CrCl at Tygerberg Hospital, identify problems associated with the procedure, and evaluate the utility of the Cockcroft-Gault (CG) and Modification of Diet in Renal Disease (MDRD) equations with different levels of renal dysfunction in the ethnic groups of the Western Cape. METHODS: A clinical audit of CrCl was performed. The estimated GFR as predicted by the modified CG and MDRD formulae was compared with CrCl in 252 patients, representing three local ethnic groups. MDRD formulae with and without the correction factor for black ethnic group (MDRD-B) were evaluated. RESULTS: Problems with urine collection or data supplied were identified in one-third of CrCl requests, leading to unreliable results. The CG correlated best with CrCl in the group as a whole. The average absolute and percentage differences from CrCl in the different ethnic groups were as follows: coloured (mixed ethnicity) (N = 186) - CG 13.4 ml/min/1.73 m(2) (18%), MDRD 16.8 ml/min/1.73 m(2) (23%) and MDRD-B 27.9 ml/ min/1.73 m(2) (38%); black (N = 21) - CG 14.8 ml/min/1.73 m(2) (19%), MDRD 12.9 ml/min/1.73 m(2) (17%) and MDRD-B 25.1 ml/min/1.73 m(2) (33%); white (N = 45) CG 13.5 ml/min/1.73 m2 (19%), MDRD 15.3 ml/min/1.73 m(2) (21%) and MDRD-B 24.8 ml/min/1.73 m(2) (35%). Throughout the renal function levels (chronic kidney disease stages 1 - 5) CG correlated better with CrCl than MDRD. CONCLUSIONS: Possible reasons for poor correlations include a high prevalence of obesity, underweight and normal GFR in the study population. There is a need for further research, using a gold standard, into the accuracy of these prediction equations in our unique patient populations before firm recommendations can be made regarding their use. Until then CrCl will continue to be widely used. Greater efforts at patient and health care worker education are required to ensure proper collections. 相似文献
7.
Akbar F Heinonen S Pirskanen M Uimari P Tuomainen TP Salonen JT 《Molecular human reproduction》2005,11(1):73-77
Association between pre-eclampsia (PEE1) and the dimethylarginine dimethylaminohydrolase (DDAH) 1 and 2 genes, which play a role in the regulation of nitric oxide synthesis and release, was studied. In a case-control study design single nucleotide polymorphisms (SNPs) were determined at eight sites in the DDAH1 gene and at one site (Pro231Pro) in the DDAH2 gene from 132 women with pre-eclampsia and 112 healthy controls. Three SNPs in the DDAH1 gene were associated with pre-eclampsia, showing complete linkage disequilibrium with each other, but none of the associations in the allele or genotype data reached statistical significance in either of the genes after the correction for multiple testing. Haplotype frequencies were estimated using a population based on a maximum likelihood method (EM algorithm). Four common DDAH1 haplotypes were present and a significant association of haplotypes H2 and H3 with pre-eclampsia (P=0.03) was found. The risk of pre-eclampsia was greatest in individuals (odds ratio: 3.93; 95% confidence interval: 1.54-9.99) who had two copies of the high-risk haplotypes (H2 or H3). The observed haplotypic association provides the first evidence of the importance of DDAH1 polymorphisms in pre-eclampsia susceptibility. 相似文献
8.
Expression of the Bovine Leukemia Virus Envelope Glycoprotein (gp51) by Recombinant Baculovirus and Its Use in an Enzyme-Linked Immunosorbent Assay
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Antonio De Giuseppe Francesco Feliziani Domenico Rutili Gian Mario De Mia 《Clinical and Vaccine Immunology : CVI》2004,11(1):147-151
The gene encoding the major envelope glycoprotein (gp51) with its signal sequence, represented by an additional NH2-terminal 33-residue amino acid sequence of bovine leukemia virus (BLV), was inserted into a baculovirus transfer vector. A recombinant virus expressing a secreted gp51 protein in insect cells was isolated. The recombinant gp51 expressed was characterized by using an anti-BLV monoclonal antibody by both Western blotting analysis and enzyme-linked immunosorbent assay (ELISA). The secreted gp51 was used as an antigen, and an ELISA with recombinant gp51 (rgp51) was developed for the detection of BLV antibodies. This new procedure was compared with a previous ELISA method for the detection of BLV antibodies and an agar gel immunodiffusion test performed with an unpurified BLV antigen preparation. The comparative testing of field samples showed that the ELISA with rgp51 is more specific and also suitable for the testing of pooled sera. 相似文献
9.
Glucocerebrosidase is a lysosomal enzyme responsible for hydrolysis of glucosylceramide to ceramide and glucose. Mutations disrupting the function of this enzyme cause autosomal recessive Gaucher disease. This disease is very heterogeneous. The clinical heterogeneity is due to a large number of mutations within the gene encoding glucocerebrosidase. To date 36 mutations have been described in Gaucher disease. In this part we present the mutations and review the more common ones. We also review the glucocerebrosidase natural activator, designated saposin C and mutations in its gene, associated with Gaucher disease. © 1994 Wiley-Liss, Inc. 相似文献
10.
Catry B Haesebrouck F Vliegher SD Feyen B Vanrobaeys M Opsomer G Schwarz S Kruif AD 《Microbial drug resistance (Larchmont, N.Y.)》2005,11(4):387-394
To measure the level of antimicrobial resistance in potential bovine respiratory pathogens at different production types, nasal swabs were collected from 57 calves of 13 dairy herds, 150 calves of 9 beef cattle herds, and 289 calves of 5 high-density veal calf herds and investigated for the presence of Pasteurellaceae. All calves were less than 6 months old. Susceptibilities of the Pasteurella and Mannheimia isolates to eight antimicrobials were determined using an agar dilution method. P. multocida (37.3%) and hemolytic Mannheimia organisms (M. haemolytica sensu lato) (6.3%) were the most frequently detected organisms. The overall prevalence of isolates resistant to at least one antimicrobial from the dairy, beef, and veal calves were 17.6% (6/34), 21.9% (14/64), and 71.9% (64/89), respectively. In isolates obtained on the veal calf herds, acquired resistance to ampicillin, oxytetracycline, potentiated sulfonamides, gentamicin, tilmicosin, and enrofloxacin was frequently present, and 32.6% of these isolates were resistant to more than two of the tested antimicrobials. Resistance to ceftiofur and florfenicol was not detected. A substantial within-herd variability of species diversity and resistance profiles among isolates belonging to the genera Pasteurella and Mannheimia was found among the isolates of the veal calf farms. 相似文献