Search results for "Density"
showing 10 items of 4402 documents
Complement C6 deficiency protects against diet-induced atherosclerosis in rabbits.
1998
Abstract —Low-density lipoprotein (LDL) can be transformed to an atherogenic moiety by nonoxidative, enzymatic degradation. Enzymatically degraded LDL induces macrophage foam cell formation, provokes release of cytokines, and also activates complement. To determine whether complement activation may contribute to atherogenesis, 6 pairs of homozygous C6-deficient rabbits and their non–C6-deficient heterozygous siblings were fed a cholesterol-rich diet for 14 weeks. Cholesterol levels and plasma lipoprotein profiles of the animals in the C6-competent and C6-deficient groups did not significantly differ, and the high density lipoprotein and LDL cholesterol ratios at the end of the experiment w…
Estrogen receptor alpha polymorphism modifies the association between childhood exercise and bone mass: follow-up study.
2007
This follow-up study confirms our previous findings that the ER-α PvuII polymorphism (Pp) modulates the association between exercise and bone mass. The differences in bone properties of girls with consistently low physical activity (LLPA) and consistently high physical activity (HHPA) were evident only in those bearing the heterozygote ER-α genotype (Pp). In particular, areal bone mineral density of the total femur, bone mineral content and areal bone mineral density of the femoral neck, and bone mineral content and cortical thickness of the tibia shaft were significantly (p < .05) lower in the Pp girls with LLPA than in their HHPA counterparts. These findings might partly explain the ge…
Die Hochenergetische Extrakorporale Stoßwellentherapie (ESWT) in der Behandlung von Pseudarthrosen
2008
PROBLEM The success rate of high-energy extracorporal shock wave therapy in the treatment of non-unions in comparison to the "golden standard" surgery is still unclear. METHOD In a prospective study, 3000 impulses with an energy density of 0.6 mJ/mm2 were applied with an experimental device to the pseudarthrosis in 52 patients. RESULTS The mean duration of pseudarthrosis was 13 months. A mean of 2.5 surgical interventions had already been performed. Bony union was achieved in 52% of our patients after an average of 3.3 months. Failures especially were found in the atrophic type of pseudarthrosis as well as in congenital bone disorders like fibrous dysplasia or osteogenesis imperfecta. No se…
The Val432Leu polymorphism of the CYP1B1 gene is associated with differences in estrogen metabolism and bone density.
2009
Polymorphisms of the CYP450 genes that encode for the enzymes that metabolize estrogen are linked to hormone-related cancers. We investigated the impact of two polymorphisms of the CYP1B1 gene previously reported to be associated with hormone-related disorders on estrogen metabolism and bone mineral density (BMD), another hormone-dependent condition, in women from different ethnic backgrounds. Four hundred sixty-eight postmenopausal Caucasian women, 220 from St. Louis, MO, USA (mean age=63.5+/-0.53 years) and 248 from Palermo, Italy (mean age=72.9+/-0.44 years) participated in the study. Measurements of urinary estrogen metabolites by enzyme-linked immunoassay, serum estradiol by ultrasensi…
Effects of polymorphisms of the sex hormone-binding globulin (SHBG) gene on free estradiol and bone mineral density.
2009
Polymorphisms of the sex hormone-binding globulin (SHBG) gene are associated with differences in SHBG levels, influencing the risk for breast cancer and polycystic ovarian syndrome, but no association has been reported for osteoporosis in postmenopausal women.To determine the effect of G to A substitution in the 5'UTR (rs1799941) and the Asp356Asn (rs6259) polymorphisms of the SHBG gene on bone mineral density (BMD).This is a cross-sectional study in a university-based research center from May, 2002 to December, 2007. A total of two hundred and thirteen healthy postmenopausal Caucasian womenor = 1 year from last menstrual period participated to this study. Serum estradiol by ultrasensitive …
Change in bone mass distribution induced by hormone replacement therapy and high-impact physical exercise in post-menopausal women.
2002
The purpose of this intervention trial was to determine whether changes in bone mass distribution could be observed in postmenopausal women following hormone replacement therapy (HRT) and/or high-impact physical exercise. Eighty healthy women, aged 50-57 years, at5 years after the onset of menopause and with no previous use of HRT, were randomly assigned to one of four groups: HRT; exercise (Ex); HRT + Ex (ExHRT); and control (Co). HRT administration was conducted in a double-blind manner for 1 year using estradiol plus noretisterone acetate (Kliogest). The exercise groups participated in a 1 year progressive training program consisting of jumping and bounding activities. Subjects participa…
Effect of alendronate and exercise on bone and physical performance of postmenopausal women: a randomized controlled trial.
2003
In this randomized, double-blind, placebo-controlled 12-month trial we evaluated effects of weight- bearing jumping exercise and oral alendronate, alone or in combination, on the mass and structure of bone, risk factors for falling (muscle strength and power, postural sway, and dynamic balance), and cardiorespiratory fitness in postmenopausal women. A total of 164 healthy, sedentary, early postmenopausal women were randomly assigned to one of four experimental groups: (1) 5 mg of alendronate daily plus progressive jumping exercise, (2) 5 mg alendronate, (3) placebo plus progressive jumping exercise, or (4) placebo. The primary endpoint was 12-month change in bone mass and geometry (measured…
The population-based prevalence of osteoporotic vertebral fracture and densitometric osteoporosis in postmenopausal women over 50 in Valencia, Spain …
2010
Purpose: To estimate the prevalence of vertebral fracture and densitometric osteoporosis in postmenopausal women over the age of 50 in Valencia, Spain. Methods: This cross-sectional study was conducted in 2006-2007. An age-stratified population-based random sample of 824 postmenopausal women over the age of 50 answered a questionnaire and received a densitometric examination of the lumbar spine and hip with dual-energy X-ray absorptiometry and a lateral X-ray of the thoracic spine and lumbar regions. Osteoporosis was defined as a T-score less than or equal to -2.5 compared to a population of young women, and the presence of vertebral fractures was classified according to Genant's semiquanti…
Weight-bearing, muscle loading and bone mineral accrual in pubertal girls--a 2-year longitudinal study.
2007
Abstract Objectives: The mechanical environment is considered to be the most important determinant of bone strength. Local muscle force, in turn, is regarded as the largest source of loading applied to bones. However, the effect of weight-bearing on bone mineral accrual is unclear. Comparing the relationship between muscle force and bone mineral content (BMC) in the upper and lower limbs provides a means of investigating this issue. Subjects and methods : The study group comprised 258 healthy girls aged 10–13 years old at baseline. BMC, lean body mass (LM) and fat body mass (FM) of total body were assessed by dual-energy X-ray absorptiometry at baseline and 2 years after. The maximal isomet…
The effect of oral hormone replacement therapy on lipoprotein profile, resistance of LDL to oxidation and LDL particle size
2001
Abstract Objectives: To disclose if oral estradiol (E 2 ), alone or in combination with natural progesterone (P) or medroxyprogesterone acetate (MPA), may modify the oxidizability of low density lipoprotein (LDL), and if the effect is achieved at physiological dosages. LDL oxidizability was assessed by the resistance to oxidation by copper and by the particle size profile, since small particles have increased oxidation susceptibility. Methods: Thirty-three women received two consecutive, two-month length doses of 1 and 2 mg/day of oral E 2 . They were then randomly assigned to a fourteen-day treatment of 2 mg/day E 2 plus either 300 mg/day P or 5 mg/day MPA. A parallel group of experiments …