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101.
102.
Background and purpose:
Angiotensin II receptor antagonists (ARBs), originally developed for antihypertensive properties, have pleiotropic effects including direct vascular actions. We tested the hypothesis that the ARB irbesartan would be effective against micro- and macrovascular complications of the prediabetic metabolic syndrome using the obese, insulin-resistant JCR : LA-cp rat that exhibits micro- and macrovascular disease with ischaemic myocardial lesions and renal disease.Experimental approach:
Obese male rats were treated with irbesartan (30 mg·kg−1·day−1, incorporated into chow) from 12 to 25 weeks of age.Key results:
Irbesartan treatment caused no change in food intake or body weight. Fasting glycaemic control of the JCR : LA-cp rats was marginally improved, at the expense of increased plasma insulin levels (∼50%). Fasting plasma triglycerides were marginally reduced (∼25%), while cholesterol concentrations were unchanged. Elevated concentrations of adiponectin, monocyte chemotactic protein-1 and plasminogen activator inhibitor-1 were reduced along with severity of glomerular sclerosis. Macrovascular dysfunction (aortic hypercontractile response to noradrenergic stimulus and reduced endothelium-dependent relaxation) was improved and frequency of ischaemic myocardial lesions reduced (62%).Conclusions and implications:
Irbesartan reduces markers of inflammation and prothombotic status, improves macrovascular function and reduces glomerular sclerosis and myocardial lesions in a model of the metabolic syndrome. Unlike pharmaceutical agents targeted on metabolic dysfunction, irbesartan reduced end-stage disease without major reduction of plasma lipids or insulin. The protective effects appear to be secondary to unknown intracellular mechanisms, probably involving signal transduction pathways. Understanding these would offer novel pharmaceutical approaches to protection against cardiovascular disease. 相似文献103.
JACQUELINE CHAUVET WON-JAE LEE MARIE-THRSE CHAUVET ROGER ACHER 《Chemical biology & drug design》1994,44(2):130-138
The two types of neurophysins known in vertebrate species, namely MSEL-neurophysin (vasopressin-like hormone-associated neurophysin) and VLDV-neurophysin (oxytocin-like hormone-associated neurophysin) have been purified from the pollack (Pollachius virens) pituitary through a combination of molecular sieving and high-pressure liquid chromatography (HPLC). Homogeneity has been checked by gel electrophoresis and rerun in HPLC. The apparent molecular masses measured by SDS-electrophoresis are near 12 kDa, significantly higher than those found for their mammalian homologues (10 kDa). The two types of neurophysins have been recognized through their N-terminal amino acid sequences. The primary structure of MSEL-neurophysin has been partially determined using automated Edman degradation applied on native and reduced-alkylated protein, as well as peptides derived by trypsin or staphylococcal proteinase hydrolyses. Comparison of pollack MSEL-neurophysin with ox, goose and frog counterparts reveals that particular positions in the polypeptide chain are subjected to substitutions and that the numbers of substitutions do not seem closely related to the paleontological times of divergence between the different vertebrate classes. 相似文献
104.
A prospective study of methylenetetrahydrofolate reductase and methionine synthase gene polymorphisms, and risk of colorectal adenoma 总被引:8,自引:2,他引:8
Chen J; Giovannucci E; Hankinson SE; Ma J; Willett WC; Spiegelman D; Kelsey KT; Hunter DJ 《Carcinogenesis》1998,19(12):2129-2132
We examined the relationship between a functional polymorphism (667C--
>T, ala-->val) of the methylenetetrahydrofolate reductase gene
(MTHFR) and the risk of colorectal adenomas in the prospective Nurses'
Health Study. Among 257 incident polyp cases and 713 controls, the MTHFR
val/val polymorphism [relative risk (RR) = 1.35, 95% confidence interval
(CI) 0.84-2.17] was not significantly associated with risk of adenomas.
This lack of association was observed for both small (RR = 1.36, 95% CI
0.76-2.45) and large (RR = 1.32, 95% CI 0.66-2.66) adenomas. Furthermore,
there was no significant interaction between this polymorphism and
consumption of either folate, methionine or alcohol. We also examined the
relationship of a newly identified polymorphism (asp919gly) of the
methionine synthase gene (MS) with the risk of colorectal adenomas in the
same population. The MS gly/gly polymorphism was also not significantly
associated with risk of colorectal adenomas (RR = 0.66, 95% CI 0.26-1.70).
These results, which need to be confirmed in other studies, suggest that
the MTHFR val/val polymorphism, which has been previously inversely
associated with risk of colorectal cancer, plays a role only in a late
stage (adenoma-- >carcinoma) of colorectal tumorigenesis, and/or may
protect against malignant transformation in the subset of benign adenomas,
which may progress to malignancy.
相似文献
105.
DL Domingo MI Trujillo SE Council MA Merideth LB Gordon T Wu WJ Introne WA Gahl TC Hart 《Oral diseases》2009,15(3):187-195
Objective: Hutchinson-Gilford progeria syndrome (HGPS) is a rare early-onset accelerated senescence syndrome. In HGPS, a recently identified de novo dominant mutation of the lamin A gene ( LMNA ) produces abnormal lamin A, resulting in compromised nuclear membrane integrity. Clinical features include sclerotic skin, cardiovascular and bone abnormalities, and marked growth retardation. Craniofacial features include 'bird-like' facies, alopecia, craniofacial disproportion, and dental crowding. Our prospective study describes dental, oral soft tissue, and craniofacial bone features in HGPS.
Methods: Fifteen patients with confirmed p.G608G LMNA mutation (1–17 years, seven males, eight females) received comprehensive oral evaluations. Anomalies of oral soft tissue, gnathic bones, and dentition were identified.
Results: Radiographic findings included hypodontia ( n = 7), dysmorphic teeth ( n = 5), steep mandibular angles ( n = 11), and thin basal bone ( n = 11). Soft tissue findings included ogival palatal arch ( n = 8), median sagittal palatal fissure ( n = 7), and ankyloglossia ( n = 7). Calculated dental ages (9 months to 11 years 2 months) were significantly lower than chronological ages (1 year 6 months to 17 years 8 months) ( P = 0.002). Eleven children manifested a shorter mandibular body, anterior/posterior cranial base and ramus, but a larger gonial angle, compared to age/gender/race norms.
Conclusion: Novel oral-craniofacial phenotypes and quantification of previously reported features are presented. Our findings expand the HGPS phenotype and provide additional insight into the complex pathogenesis of HGPS. 相似文献
Methods: Fifteen patients with confirmed p.G608G LMNA mutation (1–17 years, seven males, eight females) received comprehensive oral evaluations. Anomalies of oral soft tissue, gnathic bones, and dentition were identified.
Results: Radiographic findings included hypodontia ( n = 7), dysmorphic teeth ( n = 5), steep mandibular angles ( n = 11), and thin basal bone ( n = 11). Soft tissue findings included ogival palatal arch ( n = 8), median sagittal palatal fissure ( n = 7), and ankyloglossia ( n = 7). Calculated dental ages (9 months to 11 years 2 months) were significantly lower than chronological ages (1 year 6 months to 17 years 8 months) ( P = 0.002). Eleven children manifested a shorter mandibular body, anterior/posterior cranial base and ramus, but a larger gonial angle, compared to age/gender/race norms.
Conclusion: Novel oral-craniofacial phenotypes and quantification of previously reported features are presented. Our findings expand the HGPS phenotype and provide additional insight into the complex pathogenesis of HGPS. 相似文献
106.
Wetting HL Hadler-Olsen E Magnussen S Rikardsen O Steigen SE Sundkvist E Loennechen T Kanapathippillai P Kildalsen H Winberg JO Uhlin-Hansen L Svineng G 《The American journal of pathology》2011,178(5):2389-2396
Increased expression of the invasion- and metastasis-associated protein S100A4 is found in many types of cancer, but the regulation of S100A4 expression is poorly understood. The microenvironment surrounding tumors has a significant effect on tumor progression, and in the present study, we investigated the role of the microenvironment in the expression of S100A4. Tumors of three different human carcinoma cell lines were established in the tongue or skin of mice, and S100A4 expression was assessed by quantitative RT-PCR, Western blotting, and immunohistochemical analysis in tumors and stromal tissue and in cancer cells grown in vitro. Tongue tumors of the oral squamous cell carcinoma cell line HSC-4 showed a pronounced increase in S100A4 expression during tumor growth, whereas only a minor increase was detected in skin tumors of the same cell line. The S100A4 expression correlated with the methylation status of cytosine-guanine sites in the first intron of the gene. For all cell lines, S100A4 expression in the tumor stroma was related to the presence of inflammatory cells rather than to the level of S100A4 in the tumor cells. 相似文献
107.
Oddo M Levine JM Mackenzie L Frangos S Feihl F Kasner SE Katsnelson M Pukenas B Macmurtrie E Maloney-Wilensky E Kofke WA Leroux PD 《中华神经外科疾病研究杂志》2011,(5):452-452
Background:Brain hypoxia(BH)can aggravate outcome after severe traumatic brain injury(TBI).Whether BH or reduced brain oxygen(Pbto2)is an independent outcome predictor or a marker of disease severity is not fully elucidated.Objective To analyze the relationship between Pbto2,intracranial pressure(ICP),and cerebral perfusion pressure(CPP)and to examine whether BH correlates with worse outcome independently of ICP and CPP.Methods We studied103patients monitored 相似文献
108.
Objective
To evaluate the therapeutic effects of the embedding needle therapy in the preventative treatment of chronic migraine.Methods
A total of 36 patients with chronic migraine were divided into an embedding needle therapy group and a flunarizine group according to random number table, 18 cases in each group. In the embedding needle therapy group, the thumb-tack needles were used at Sīzhúkōng (丝竹空TE 23), Hànyàn (颔厌GB 4), Wáng? (完骨GB 12) and Cuánzhú (攒竹BL 2) and the needles were embedded for 24 h. The embedding needle therapy was given three times a week. In the flunarizine group, flunarizine was prescribed, 10 mg a day. Separately, at the end of the 4-week treatment and in 4 weeks of the follow-up, the number of days of headache attack per month (days/month) and the headache duration (hours/month) in the cases with moderate to severe headache were observed in the two groups.Results
The number of days of headache attack in the cases with moderate to severe headache was reduced after treatment as compared with the number before treatment in the two groups. The headache duration was reduced obviously after treatment in the cases of moderate to severe headache in the two groups. In the 4-week follow-up, all the indexes were still reduced as compared with the indexes before treatment, indicating the significant differences in the two groups (both P < 0.05). In the embedding needle therapy group, at the end of the 4-week treatment and in 4 weeks of the follow-up, the number of days of headache attack per month was (8.1 ± 2.4) days and (7.2 ± 1.6) days separately, which were significant difference as compared with (9.7 ± 2.3) days and (8.9 ± 1.4) days in the flunarizine group (both P < 0.05). Regarding the headache duration, at the end of the 4-week treatment and in 4 weeks of the follow-up, it was (105.6 ± 10.5) h/month and (92.1 ± 7.2) h/month respectively in the embedding needle therapy group, indicating the significant differences as compared with (135.4 ± 8.9) h and (116.1 ± 8.2) h in the flunarizine group respectively (both P < 0.05).Conclusion
The 4-week treatment with the embedding needle therapy obviously reduces the number of days of headache attack and the headache duration, presents the preventative effects in the patients with chronic migraine. 相似文献109.
110.