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991.
Irene Lambrinoudaki George Kaparos† Demetrios Rizos† Fotini Galapi reas Alexandrou‡ Theodoros N. Sergentanis Maria Creatsa George Christodoulakos E. Kouskouni† D. Botsis 《Clinical endocrinology》2009,71(2):284-290
Objective Autoimmune thyroiditis and overt or subclinical hypothyroidism have been associated with increased prevalence of cardiovascular disease (CVD).
Design Cross-sectional investigation of the association between gene polymorphisms related to CVD with thyroid function and autoimmunity.
Patients In total 84 healthy postmenopausal women aged 49–69 years.
Measurements FT3, FT4, anti-TPO and anti-TG were assessed in the sera of participants. The following polymorphisms were assessed from peripheral lymphocyte DNA: Apolipoprotein E E2/E3/E4, paraoxonase 1 A/B, Glycoprotein IIIa leu33pro, MTHFR ala222val, ApoBarg3500gln, plasminogen activator inhibitor 1 4G/5G, cholesterol 7-α hydroxylase A204C and cholesterol ester transfer protein B1/B2.
Results A statistically significant correlation was found between Apolipoprotein E and paraoxonase1 polymorphisms and serum thyroid hormones: carriers of the E2 or E4 allele of the ApoE gene had lower levels of FT4 ( P = 0·0005) than women with the E3/E3 genotype. Carriers of the B allele of paraoxonase 1 gene had lower levels of FT3 compared to women with the wild-type genotype ( P = 0·047). A statistically significant positive association ( P = 0·049) was also observed between anti-TG antibodies and the presence of the E2 allele of the Apolipoprotein E gene.
Conclusions Polymorphisms of apolipoprotein E and paraoxonase 1 are associated with different levels of thyroid hormone and anti-Tg antibody levels in the study population in this pilot study. The mechanism underlying this association remains to be elucidated. 相似文献
Design Cross-sectional investigation of the association between gene polymorphisms related to CVD with thyroid function and autoimmunity.
Patients In total 84 healthy postmenopausal women aged 49–69 years.
Measurements FT3, FT4, anti-TPO and anti-TG were assessed in the sera of participants. The following polymorphisms were assessed from peripheral lymphocyte DNA: Apolipoprotein E E2/E3/E4, paraoxonase 1 A/B, Glycoprotein IIIa leu33pro, MTHFR ala222val, ApoBarg3500gln, plasminogen activator inhibitor 1 4G/5G, cholesterol 7-α hydroxylase A204C and cholesterol ester transfer protein B1/B2.
Results A statistically significant correlation was found between Apolipoprotein E and paraoxonase1 polymorphisms and serum thyroid hormones: carriers of the E2 or E4 allele of the ApoE gene had lower levels of FT4 ( P = 0·0005) than women with the E3/E3 genotype. Carriers of the B allele of paraoxonase 1 gene had lower levels of FT3 compared to women with the wild-type genotype ( P = 0·047). A statistically significant positive association ( P = 0·049) was also observed between anti-TG antibodies and the presence of the E2 allele of the Apolipoprotein E gene.
Conclusions Polymorphisms of apolipoprotein E and paraoxonase 1 are associated with different levels of thyroid hormone and anti-Tg antibody levels in the study population in this pilot study. The mechanism underlying this association remains to be elucidated. 相似文献
992.
993.
Cecilia Soledad Blengini Maria Eugenia Teves Diego Rafael Ufiates Hetor Alejandro Guidobaldi LauraVirginia Gatica Laura Cecilia Giojalas 《Asian journal of andrology》2011,13(5):769-773
Human spermatozoa may chemotactically find out the egg by following an increasing gradient of attractant molecules. Although human spermatozoa have been observed to show several of the physiological characteristics of chemotaxis, the chemotactic pattern of movement has not been easy to describe. However, it is apparent that chemotactic cells may be identified while returning to the attractant source. This study characterizes the pattern of movement of human spermatozoa during chemotactic re-orientation towards a progesterone source, which is a physiological attractant candidate. By means of videomicroscopy and image analysis, a chemotactic pattern of movement was identified as the spermatozoon returned towards the source of a chemotactic concentration of progesterone (10 pmol l−1). First, as a continuation of its original path, the spermatozoon swims away from the progesterone source with linear movement and then turns back with a transitional movement that can be characterized by an increased velocity and decreased linearity. This sperm behaviour may help the spermatozoon to re-orient itself towards a progesterone source and may be used to identify the few cells that are undergoing chemotaxis at a given time. 相似文献
994.
995.
996.
997.
Maria P. McGee MD Michael J. Morykwas PhD Louis C. Argenta MD 《Wound repair and regeneration》2011,19(3):358-367
The local pathogenesis of interstitial edema in burns is incompletely understood. This ex vivo study investigates the forces mediating water‐transfer in and out of heat‐denatured interstitial matrix. Experimentally, full‐thickness dermal samples are heated progressively to disrupt glycosaminoglycans, kill cells, and denature collagen under conditions that prevent water loss/gain; subsequently, a battery of complementary techniques including among others, high‐resolution magnetic resonance imaging, equilibrium vapor pressure and osmotic stress are used to compare water‐potential parameters of nonheated and heated dermis. The hydration potential (HP) determined by osmotic stress is a measure of the total water‐potential defined empirically as the pressure at which no net water influx/efflux into/from the dermis is detected. Results show that after heat denaturation, the HP, the intensity of T2‐weighed magnetic resonance images, and the vapor pressure increase indicating higher water activity and necessarily, smaller contributions from colloidosmotic forces to fluid influx in burned relative to healthy dermis. Concomitant increases in HP and in water activity implicate local changes in interfacial and metabolic energy as the source of excess fluid‐transfer potential. These ex vivo findings also show that these additional forces contributing to abnormal fluid‐transfer in burned skin develop independently of inflammatory and systemic hydrodynamic responses. 相似文献
998.
Gentilucci UV Picardi A Manfrini S Khazrai YM Fioriti E Altomare M Guglielmi C Di Stasio E Pozzilli P 《Diabetes/metabolism research and reviews》2008,24(5):364-370
BACKGROUND: Aims of the present study were to examine the anthropometrical and metabolic characteristics of the Filipino population migrant to the Southern European city of Rome, Italy. METHODS: A cross-sectional study was carried out in the city of Rome. Three hundred thirty-five Filipinos (95 M/240 F, mean age: 44.0+/-9.8 years, mean residence in Italy: 12.9+/-6.3 years) were studied. Data were collected by standardized questionnaires; anthropometrical parameters, arterial pressure, and fasting capillary blood glucose (FCG) were measured. RESULTS: Abdominal obesity was found in 52.5%, and BMI >or= 25 kg/m(2) in 44.5% of subjects. History of type 2 diabetes mellitus (T2DM) and hypertension were reported by 6.0 and 9.0% of subjects, respectively. Impaired fasting glucose was found in 13.1%, and FCG >or= 110 mg/dl in 18.5% of subjects. Altered systolic and/or diastolic blood pressure was found in 34.3% of subjects. About three-fourths of subjects were unaware of being diabetic and/or hypertensive. Years of Italy residence showed a direct significant correlation with the degree of changes in alimentary behaviours (rho=0.18, p=0.001), and with weight gain (rho=0.27, p<0.001). Multivariate analysis showed only age and waist circumference to be associated with both diabetes and hypertension. CONCLUSIONS: In the present study, the first to examine the metabolic disorders in a migrant Filipino population resident in Rome, a high prevalence of obesity, diabetes, and hypertension was found. The alarming results emerging from this study should be seriously considered by public health practitioners and decision makers, and made known to the Filipinos resident in Europe. 相似文献
999.
Schulpis KH Papassotiriou I Vounatsou M Karikas GA Tsakiris S Chrousos GP 《The Journal of clinical endocrinology and metabolism》2004,89(8):3983-3987
Patients with phenylketonuria (PKU) have a diet-controlled deficiency in the conversion of phenylalanine (Phe) to tyrosine (Tyr), leading to decreased production of noradrenaline, adrenaline, and dopamine. Poor diet control results in high plasma Phe and low plasma Tyr and catecholamine concentrations. Ghrelin, a recently described gastrointestinal hormone that is elevated in the fasting state and low in the fed state, is considered a major appetite-stimulating hormone, possibly involved in the generation of obesity and insulin resistance. We evaluated morning preprandial plasma ghrelin levels in 14 diet-controlled and 15 poorly controlled PKU patients and 20 age- and body mass index (BMI)-matched healthy children (controls) and correlated its concentrations with those of Phe and catecholamines as well as with their BMI and 24-h nutrient intake. Plasma ghrelin levels were measured by RIA, plasma catecholamine concentrations were determined by HPLC with electrochemical detection, and Phe and Tyr levels were measured in an amino acid analyzer. The ghrelin concentration (744 +/- 25 ng/liter) in diet-controlled patients did not differ from that in controls (802 +/- 26 ng/liter; P > 0.05). On the contrary, the ghrelin concentration was significantly reduced in poorly controlled patients (353 +/- 23 ng/liter; P < 0.0001). Ghrelin correlated negatively with Phe in all three groups, whereas it correlated positively with catecholamine levels and energy intake and negatively with BMI only in diet-controlled patients and controls. We conclude that ghrelin secretion may receive positive direct or indirect input from catecholamines. The absence of a correlation between ghrelin and catecholamines, energy intake, or BMI in PKU patients on an inadequate diet may be due to dysregulation of their neuroendocrine system and might be affected by high Phe levels in the stomach and/or central nervous system. 相似文献
1000.
Peran L Camuesco D Comalada M Nieto A Concha A Diaz-Ropero MP Olivares M Xaus J Zarzuelo A Galvez J 《World journal of gastroenterology : WJG》2005,11(33):5185-5192
AIM: To investigate the intestinal anti-inflammatory effect and mechanism of a probiotic Lactobacillus salivarius ssp. salivarius CECT5713 in the TNBS model of rat colitis. METHODS: Female Wistar rats (180-200 g) were used in this study. A group of rats were administered orally the probiotic L. salivarius ssp. salivarius(5×108 CFU suspended in 0.5 mL of skimmed milk) daily for 3 wk. Two additional groups were used for reference, a non-colitic and a control colitic without probiotic treatment, which received orally the vehicle used to administer the probiotic. Two weeks after starting the experiment, the rats were rendered colitic by intracolonic administration of 10 mg of TNBS dissolved in 0.25 mL of 500 mL/L ethanol. One week after colitis induction, all animals were killed and colonic damage was evaluated both histologically and biochemically. The biochemical studies performed in colonic homogenates include determination of myeloperoxidase (MPO) activity, glutathione (GSH) content, leukotriene B4 (LTB4) and tumor necrosis factor a (TNF-α) levels, as well as inducible nitric oxide synthase (iNOS) expression. In addition, the luminal contents obtained from colonic samples were used for microbiological studies, in order to determine Lactobacilli and Bifidobacteria counts. RESULTS: Treatment of colitic rats with L salivarius ssp. salivarius resulted in amelioration of the inflammatory response in colitic rats, when compared with the corresponding control group without probiotic treatment. This anti-inflammatory effect was evidenced macroscopically by a significant reduction in the extent of colonic necrosis and/or inflammation induced by the administration of TNBS/ethanol (2.3±0.4 cm vs 53.4±0.3 cm in control group, P<0.01) and histologically by improvement of the colonic architecture associated with a reduction in the neutrophil infiltrate in comparison with non-treated colitic rats. The latter was confirmed biochemically by a significant reduction of colonic MPO activity (105.3±26.0 U/g vs 180.6±21.9 U/g, P<0.05) a marker of neutrophil infiltration. The beneficial effect was associated with an increase of the colonic GSH content (1 252±42 nmol/g vs 1 087±51 nmol/g,P<0.05), which is depleted in colitic rats, as a consequence of the oxidative stress induced by the inflammatory process. In addition, the treatment of colitic rats with L. salivarius resulted in a significant reduction of colonic TNF-α levels (509.4±68.2 pg/g vs 782.9±60.1 pg/g, P<0.01) and in a lower colonic iNOS expression, when compared to TNBS control animals without probiotic administration. Finally, treated colitic rats showed higher counts of Lactobacilli species in colonic contents than control colitic rats, whereas no differences were observed in Bifidobacteria counts. CONCLUSION: Administration of the probiotic L. salivarius ssp. salivarius CECT5713 facilitates the recovery of the inflamed tissue in the TNBS model of rat colitis, an effect associated with amelioration of the production of some of the mediators involved in the inflammatory response in the intestine, such as cytokines, including TNF-α and NO. This beneficial effect could be ascribed to its effect on the altered immune response that occurs in this inflammatory condition. 相似文献