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Strahlentherapie und Onkologie - 相似文献
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Genetic predisposition for adult lactose intolerance and relation to diet, bone density, and bone fractures. 总被引:8,自引:0,他引:8
Barbara M Obermayer-Pietsch Christine M Bonelli Daniela E Walter Regina J Kuhn Astrid Fahrleitner-Pammer Andrea Berghold Walter Goessler Vinzenz Stepan Harald Dobnig Georg Leb Wilfried Renner 《Journal of bone and mineral research》2004,19(1):42-47
Evidence that genetic disposition for adult lactose intolerance significantly affects calcium intake, bone density, and fractures in postmenopausal women is presented. PCR-based genotyping of lactase gene polymorphisms may complement diagnostic procedures to identify persons at risk for both lactose malabsorption and osteoporosis. INTRODUCTION: Lactase deficiency is a common autosomal recessive condition resulting in decreased intestinal lactose degradation. A -13910 T/C dimorphism (LCT) near the lactase phlorizin hydrolase gene, reported to be strongly associated with adult lactase nonpersistence, may have an impact on calcium supply, bone density, and osteoporotic fractures in the elderly. MATERIALS AND METHODS: We determined LCT genotypes TT, TC, and CC in 258 postmenopausal women using a polymerase chain reaction-based assay. Genotypes were related to milk intolerance, nutritional calcium intake, intestinal calcium absorption, bone mineral density (BMD), and nonvertebral fractures. RESULTS: Twenty-four percent of all women were found to have CC genotypes and genetic lactase deficiency. Age-adjusted BMD at the hip in CC genotypes and at the spine in CC and TC genotypes was reduced by -7% to -11% depending on the site measured (p = 0.04). LCT(T/C-13910) polymorphisms alone accounted for 2-4% of BMD in a multiple regression model. Bone fracture incidence was significantly associated with CC genotypes (p = 0.001). Milk calcium intake was significantly lower (-55%, p = 0.004) and aversion to milk consumption was significantly higher (+166%, p = 0.01) in women with the CC genotype, but there were no differences in overall dietary calcium intake or in intestinal calcium absorption test values. CONCLUSION: The LCT(T/C-13910) polymorphism is associated with subjective milk intolerance, reduced milk calcium intake, and reduced BMD at the hip and the lumbar spine and may predispose to bone fractures. Genetic testing for lactase deficiency may complement indirect methods in the detection of individuals at risk for both lactose malabsorption and osteoporosis. 相似文献
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G. Kindermann 《Archives of gynecology and obstetrics》1995,257(1-4):107-115
Ohne Zusammenfassung 相似文献
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Andreas Ritsch Christoph Ebenbichler Elisabeth Naschberger Wilfried Schgoer Ursula Stanzl Hermann Dietrich Peter C Heinrich Kazunori Saito Josef R Patsch 《Clinical chemistry and laboratory medicine》2004,42(3):247-255
Cholesteryl ester transfer protein (CETP) greatly affects the metabolism of all lipoprotein classes including low-density lipoprotein (LDL) and high-density lipoprotein (HDL), both known to constitute powerful risk factors for coronary artery disease (CAD). We now report the successful first cloning and characterization of single-chain antibody fragments specific for CETP. A recombinant phage display library was generated using spleen mRNA isolated from BALB/c mice that had been immunized with highly purified CETP. Screening of the library yielded two single-chain antibody fragments with high affinity for CETP, termed 1CL8 and 1CL10, displaying respective KD values of 4.36 x 10(-9) M and 4.64 x 10(-9) M as determined by affinity sensor technology. Amino acid sequence comparison indicated the complementarity-determining regions of the respective heavy chains to be responsible for CETP high affinity binding. Fragment 1CL8 was successfully employed in clinical chemical quantification systems that uncovered an association in humans between plasma CETP concentration and total body fat mass (r=0.50, p<0.002). Because of the demonstrated superb CETP capturing capacity, combined with high binding affinity to CETP, ready access and unlimited supply, 1CL8 and 1CL10 are expected to prove powerful tools for studies on the role of CETP in atherogenesis. 相似文献
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Antioxidant defence during cardiopulmonary bypass surgery. 总被引:1,自引:0,他引:1
Chris R Luyten Frans J van Overveld Lieve A De Backer Anna M Sadowska Inez E Rodrigus Stefan G De Hert Wilfried A De Backer 《European journal of cardio-thoracic surgery》2005,27(4):611-616
OBJECTIVE: Cardiac surgery may lead to severe oxidative stress due to formation of oxidation products generated during ischemia and reperfusion. We investigated to which extent oxidative stress influences a number of endogenous antioxidants and markers of cellular activation. METHODS: At six time points blood was withdrawn from patients undergoing coronary artery bypass grafting, using the on-pump procedure. RESULTS: Both glutathione peroxidase and superoxide dismutase show a gradual and strong increase in activity during surgery (40 and 30%, respectively), returning to baseline values 24 h after surgery. The total antioxidant capacity has a maximum increase of 60%. Markers of cellular activation, such as eosinophil cationic protein and tryptase also increase during the procedure. CONCLUSION: Cardiac surgery results in systemic inflammation accompanied or caused by severe oxidative stress. The human body has a strong innate oxidative defence screen, which is probably not sufficient to fully compensate for the total amount of oxidative damage. 相似文献
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Sinus augmentation has been advocated to be a surgical technique with predictable results in peri‐implant surgery. Endoscopic surgery of the maxillary sinus so far has been used as diagnostic procedure. In this paper, the use of endoscopy is described as a low invasive adjunctive technique in sinus floor augmentation. After preparation of the mucoperiosteum, bone grafts can be placed under endoscopic control between sinus floor and mucoperiosteum. A laterobasal approach via a small osteotomy and a transalveolar approach are possible for mucosal elevation and graft placement. First clinical results are reported. Endoscopic sinus lift may contribute to a reduction of perioperative morbidity, reduction of oroantal fistulae and control of graft position. The less invasive technique may allow to extend the indication for sinus augmentation. 相似文献
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Behaviour of testosterone, sex hormone binding globulin (SHBG), and cortisol before and after a triathlon competition 总被引:1,自引:0,他引:1
To provide information on the duration of the regeneration phase after several hours of physical strain, venous blood samples of eight participants in a 1/4 triathlon competition were taken each day at the same time (arrival) for determinations of testosterone (T), SHBG, and cortisol (C). In addition, urea, creatinine, creatinine kinase, and the changes in plasma volume were determined. Directly after arrival, T had not changed substantially, but decreased nonsignificantly on each of the following days and obtained the lowest concentration on the 2nd day after the triathlon. T/SHBG as an expression of free testosterone was significantly reduced on the 2nd, 3rd, and 4th days after the competition. C increased up until the end of the competition by 4.5 times the original value, and during the subsequent days it decreased again to the normal range. Until the end of the observation period on the 4th day after the competition, urea was still significantly elevated. The data suggest an anabolic deficit lasting for several days as a result of prolonged physical strain. 相似文献