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1.
BACKGROUND and PURPOSE: A number of investigations support the theory that the elevated plasma homocyst(e)ine is associated with occlusive vascular disease. The aim of this study is to examine whether moderate hyperhomocyst(e)inemia is an independent risk factor for cerebral infarction. In addition, we examined the association between plasma homocyst(e)ine and the severity of cerebral atherosclerosis. METHODS: We conducted a hospital-based case-control study with 140 male controls and 78 male patients with nonfatal cerebral infarction, aged between 39 and 82 years. Plasma homocyst(e)ine levels were analyzed in 218 subjects. Fifty-five patients were evaluated for cerebral vascular stenosis by MR angiography. RESULTS: The mean plasma level of homocyst(e)ine was higher in cases than in controls (11.8+/-5.6 versus 9.6+/-4.1 micromol/L; P=0.002). The proportion of subjects with moderate hyperhomocyst(e)inemia was significantly higher in cases than in controls (16.7% versus 5.0%; P=0.004). Based on the logistic regression model, the odds ratio of the highest 5% of homocyst(e)ine levels in control group was 4.17 (95% confidence interval, 3.71 to 4. 71)(P=0.0001). After additional adjustment for total cholesterol, hypertension, smoking, diabetes, and age, the odds ratio was 1.70 (95% confidence interval, 1.48 to 1.95) (P=0.0001). The plasma homocyst(e)ine levels of patients having vessels with 3 or 2 stenosed sites were significantly higher than those of patients having vessels with 1 stenosed site or normal vessels (14.6+/-1.4, 11.0+/-1.4 versus 7.8+/-1.5, 8.9+/-1.4 micromol/L respectively; P<0. 02). Multiple logistic regression analysis revealed that moderate hyperhomocyst(e)ienemia was significantly associated with the number of stenosed vessels (P=0.001). CONCLUSIONS: These findings suggest that moderate hyperhomocyst(e)inemia is an independent risk factor for cerebral infarction and may predict the severity of cerebral atherosclerosis in patients with cerebral infarction.  相似文献   

2.
To determine whether gender differences in body fat could be detected in prepubertal children using dual energy X-ray absorptiometry (DEXA), body composition was measured in 20 healthy boys aged 3-8 y matched for age, height and weight with 20 healthy girls. Although boys and girls did not differ in age, height, weight, body mass index (BMI) or bone mineral content, the boys had a lower percentage of body fat (13.5 +/- 5.1 vs 20.4 +/- 6.1%, P < 0.01), a lower fat mass (3.2 +/- 2.0 vs 4.9 +/- 3.1 kg, P < 0.01), and a higher bone-free lean tissue mass (18.6 +/- 4.3 vs 17.0 +/- 3.5 kg, P < 0.01) than the girls. Girls had approximately 50% more body fat than the boys. This is the first DEXA study to show that boys aged 3-8 y have less body fat than girls of similar age, height and weight. Thus, this technology demonstrates that significant gender differences in body composition are evident, well before the onset of puberty.  相似文献   

3.
This study is the first to report approximations of energy requirements for male and female breast-fed and formula-fed infants based on individual estimates of total daily energy expenditure (TDEE) and energy deposition derived from total body fat (TBF) and fat-free mass (FFM) gain as determined by total-body electrical conductivity. In 46 healthy, full-term infants the effect of > or = 4 mo of exclusive breast-feeding compared with formula feeding on macronutrient and energy intake, TDEE, energy deposition, and growth were investigated prospectively. Metabolizable energy intake (MEI) was assessed from macronutrient intake by test weighing (MEI-TW) and from the sum of TDEE and energy deposition (MEI-Pred). At 1-2, 2-4, 4-8, and 8-12 mo of age MEI-Pred averaged 431 +/- 38, 393 +/- 33, 372 +/- 33, and 355 +/- 21 kJ x kg(-1) x d(-1) for boys, and 401 +/- 59, 376 +/- 25, 334 +/- 33, and 326 +/- 17 kJ x kg(-1) x d(-1) for girls. No significant difference between breast-fed and formula-fed infants was found with respect to weight, length, head circumference, TBF, FFM, and TDEE at all ages, or for gain in length, weight, TBF, and FFM. MEI-TW was significantly different between feeding groups at 1-4 mo of age (formula-fed being greater than breast-fed, P < 0.005). This feeding effect, however, was not significant for MEI-Pred (MJ/d). MEI-TW differed from MEI-Pred only in breast-fed infants at 1-4 mo (P < 0.05 at 2-4 mo). The data from this study indicate that energy requirements in infants are lower than the recommendations in guidelines currently in use.  相似文献   

4.
We established the cutoff value for plasma folic acid, using plasma homocyst(e)ine as the functional marker. To do this, we investigated the relationship of the plasma folic acid of 103 apparently healthy adults with their fasting plasma homocyst(e)ine and with their plasma homocyst(e)ine 6 h after oral methionine challenge (100 mg/kg). We also studied the relationship of their plasma folic acid with the decline of fasting plasma homocyst(e)ine after 7 days of folic acid supplementation (5 mg/day). The three approaches suggested a cutoff value of 10 nmol/L. The chances of individuals to significantly (P <0.05) lower their plasma homocyst(e)ine after folic acid supplementation proved significantly higher at plasma folic acid concentrations < or = 10 nmol/L, as compared with folic acid concentrations above this value (odds ratio, 5.02; 95% confidence interval, 1.87-13.73). We suggest adopting a 10 nmo/L plasma folic acid cutoff value on functional grounds.  相似文献   

5.
BACKGROUND: It has been assumed that a urinary creatinine excretion rate of less than 10 mg/kg per day means an inadequately collected urine sample. OBJECTIVE: To determine the frequency of a urinary creatinine excretion rate of less than 10 mg/kg per day in intensive care unit patients with an adequately collected urine sample. METHOD: In a prospective study of creatinine excretion rates, 24-hour urine samples were evaluated for urinary creatinine in 209 critically ill patients with indwelling Foley catheters. Patients from three adult intensive care units in New York City were divided into two groups. Group 1 patients excreted less than 10 mg/kg per day of urinary creatinine, and group 2 patients excreted at least 10 mg/kg per day. Groups 1 and 2 were first evaluated by dividing the creatinine excretion data by actual body weight. Since actual body weight may overestimate body weight in the critically ill patient, data from groups 1 and 2 were also evaluated using lean body weight. RESULTS: Urinary creatinine excretion was less than 10 mg/kg per day in 36.8% of patients using actual body weight and 29.7% of patients adjusted for lean body weight. The average age of patients in group 1 was 74 +/- 17 years for both actual body weight and lean body weight. The average age of group 2 patients was 60 +/- 19 years for actual body weight and 62 +/- 19 years for lean body weight. There was a significant difference in age between group 1 and group 2 patients for both actual body weight and lean body weight. The proportion of female vs male patients with reduced creatinine excretion was significantly greater, whether the actual body weight or lean body weight adjustment was used. CONCLUSIONS: A urinary creatinine excretion rate of less than 10 mg/kg per day occurs in about one third of critically ill patients, who are more likely to be elderly and female.  相似文献   

6.
OBJECTIVE: To document the profile and role of malnutrition in alcoholic hepatitis, compared with chronic alcoholics and nonalcoholic chronic liver disease. METHODS: To this end, we studied 67 patients with alcoholic liver disease (ALD) (group I), 52 chronic alcoholics without histological evidence of liver disease (group II), 44 nonalcoholic cirrhotics (group III), and 52 healthy controls (group IV). Alcoholic and nonalcoholic calories were calculated and percentage dietary and nutritional deficiencies computed. Anthropometric indices, nitrogen balance, and immune status of the patients were assessed. RESULTS: Alcohol constituted about 48% of daily caloric intake in patients with ALD. The percentage mean intake of carbohydrate, protein, and energy was decreased in all three study groups compared with controls. The deficiencies were more pronounced in patients with severe than with moderate ALD. These deficiencies were more severe in the group III patients. Whereas body fat stores were maintained in groups I and II, reduction in lean body mass and serum transferrin was significant in patients in groups I and III. In group II patients compared to group I patients, the body mass index (19.9 +/- 4.0 vs. 22.3 +/- 3.4) and triceps skinfold thickness (6.1 +/- 4.8 vs. 10.2 +/- 5.6 mm) were significantly lower. CONCLUSIONS: 1) protein energy malnutrition is common in both alcoholic and nonalcoholic cirrhotics, but is more pronounced in the latter; 2) the degree and profile of malnutrition in chronic alcoholics and in alcoholic cirrhotics are comparable; 3) based on our results, we hypothesize that malnutrition may not play a primary role in the pathogenesis of ALD.  相似文献   

7.
Racial differences in insulin secretion and insulin sensitivity in healthy children were studied by administering a 2-hour hyperglycemic clamp (225 mg/dL) to 14 black and 16 white healthy adolescents (Tanner II-V), and 12 black and 11 white prepubertal children, matched for age, body mass index, and Tanner I pubertal development. In prepubertal children, fasting and first-phase insulin concentrations were higher in blacks compared with whites (14.7+/-1.3 vs 10.4+/-1.2, P=0.02, and 76.9+/-6.8 vs 52.1+/-6.4 microu/mL, P=0.016). There were no differences in second-phase insulin levels and insulin sensitivity index. In pubertal adolescents, first-phase and second-phase insulin concentrations were higher in blacks compared with whites (first-phase: 157.3+/-18.3 vs 77.0+/-8.7 microu/mL, P=0.0003; second-phase: 175.0+/-24.3 vs 108.7+/-8.8 microu/mL, P=0.012). Insulin sensitivity index was 35% lower in black adolescents compared with whites (P=0.02). These findings indicate that significant differences in insulin secretion and sensitivity are detectable early in childhood in healthy African-American vs American whites. However, genetic (race) vs environmental factors (physical activity/fitness, energy balance) should be carefully scrutinized as potential factors responsible for such differences.  相似文献   

8.
OBJECTIVE: The purpose of the study was to test the hypothesis that dietary fat components were associated with the serum lipid profile independent of ethnicity, body fat, and fat distribution in prepubertal children. RESEARCH METHODS AND PROCEDURES: Sixty-six children (45 African American and 21 Caucasian), aged from 4 to 10 years, were recruited into the study. Dietary total fat, saturated fat, monounsaturated fat, and polyunsaturated fat were estimated by averaging two 24-hour diet recalls. Fasting serum triacylglycerol, total cholesterol, and high-density lipoprotein cholesterol were analyzed, and low-density lipoprotein cholesterol (LDL-C) was calculated by the method of Friedewald. Body composition and fat distribution were measured by dual energy X-ray absorptiometry and computed tomography. RESULTS: Children in both ethnic groups tended to overreport their dietary intake relative to total energy expenditure by 18%. African American children consumed more energy from total fat (35.3% vs. 31.5%, p<0.05), saturated fat (13.7% vs 12.2%, p<0.05), protein (16.4% vs. 13.2%, p=0.02), and less from carbohydrate (48% vs. 57.1%, p<0.01) than Caucasian children. There was no significant correlation between dietary fat and either serum lipids or body fat indices after adjusting for nonfat energy intake and total lean tissue mass. Total body fat (r=0.32), subcutaneous abdominal adipose tissue (r=0.39), and intra-abdominal adipose tissue (r=0.42) were positively related to serum triacylglycerol; these associations remained significant in a multiple linear regression model in which body fat indices were adjusted for ethnicity, total lean tissue, dietary total fat, and nonfat intake. DISCUSSION: Our results do not support a link between dietary fat and serum lipids; instead, our data suggest that body fat may play a more important role than dietary fat in the course of cardiovascular disease development in prepubertal children.  相似文献   

9.
There are many pathological changes in patients with cystic fibrosis (CF) which can lead to alterations in drug disposition. Although, in patients with CF, the extent of drug absorption varies widely and the rate of absorption is slower, bioavailability is not altered. Plasma protein binding for the majority of drugs studied did not differ in patients with CF compared with control groups. The difference in volume of distribution of most drugs between patients with CF and healthy individuals vanished when corrected for lean body mass. Despite hepatic dysfunction, patients with CF have enhanced clearance of many, but not all, drugs. Phase I mixed-function oxidases are selectively affected: cytochrome P450 (CYP) 1A2 and CYP2C8 have enhanced activity, while other CYP isoforms such as CYP2C9 and CYP3A4 are unaffected. Increased phase II activities are also demonstrated: glucuronyl transferase, acetyl transferase (NAT1) and sulfotransferase. The increased hepatic clearance of drugs in the presence of CF may be the consequence of disease-specific changes in both enzyme activity and/or drug transport within the liver. The renal clearance (CLR) of many drugs in patients with CF is enhanced although there has been no pathological abnormality identified which could explain this finding: glomerular filtration rate and tubular secretion appear normal in patients with CF. The precise mechanisms for enhanced drug clearance in patients with CF remain to be elucidated. The optimisation of antibiotic therapy in patients with CF includes increasing the dose of beta-lactams by 20 to 30% and monitoring plasma concentrations of aminoglycosides. The appropriate dosage of quinolones has not been definitively established.  相似文献   

10.
OBJECTIVE: There are few data on the endocrine mechanisms underlying the body fluid changes in GH deficiency and their subsequent alteration following GH replacement. We have therefore investigated the time effects of GH on body fluid distribution and fluid regulating hormones in GH deficient adults. DESIGN: The patients underwent in random order four study periods: (1) saline, a 42-hour infusion following 3 weeks without GH, (2) acute GH, a 42-hour GH infusion following 3 weeks without GH, (3) 3 days GH, a 42-hour GH infusion preceded by 3 weeks without GH and 3 days pretreatment with subcutaneous GH injections, (4) 3 weeks GH, a 42-hour GH infusion after at least 3 weeks GH therapy. SUBJECTS: Seven GH deficient adult males and 8 healthy control subjects. MEASUREMENTS: During each infusion period 24-hour blood pressure was recorded, bioimpedance was repeatedly measured and blood samples were obtained every 6 hours. After 41 hours extracellular and plasma volumes were determined isotopically. Extracellular volume, plasma volume and bioimpedance were measured in the control group. RESULTS: GH increased extracellular volume (saline 16.45 +/- 0.79 vs acute GH 16.83 +/- 0.87; vs 3 days GH 17.58 +/- 0.71; vs 3 weeks GH 17.92 +/- 0.88 l, P = 0.01). After 3 weeks of GH, extracellular volumes in the patients and in the control group were identical (control 17.94 +/- 0.32). Plasma volume was increased only after 3 weeks GH treatment (saline 2.93 +/- 0.16 vs acute GH 3.04 +/- 0.22; vs 3 days GH 3.06 +/- 0.07; vs 3 weeks GH 3.37 +/- 0.18 l, P = 0.03), and was decreased compared to the control group (control 3.56 +/- 0.03 l, P < 0.01). Bioimpedance decreased significantly in all treatment periods and was significantly increased compared to the control group. Plasma renin increased during GH administration (saline 16.2 +/- 1.9 vs acute 19.0 +/- 1.9; vs 3 days GH 30.8 +/- 3.0; vs 3 weeks GH 27.0 +/- 3.0 mU/l, P = 0.03), whereas aldosterone and atrial natriuretic factor (ANF) levels remained unaffected by GH. GH caused an increase in systolic blood pressure (BP) and heart rate, whereas diastolic BP remained unaffected. CONCLUSIONS: The present data show that GH deficiency is associated with decreased plasma volume and extracellular volume. GH exposure acutely increases extracellular volume, whereas substitution for a longer time was required to normalize both extracellular and plasma volumes. Renin seems to be involved in these fluid volume regulating effects of GH.  相似文献   

11.
OBJECTIVE: To assess the level of serum lipoprotein(a) [Lp(a)] in nonobese and obese NIDDM subjects with android body distribution. RESEARCH DESIGN AND METHODS: Serum Lp(a) levels were measured in 30 long-standing NIDDM patients (duration of diabetes 12.5 +/- 3 years, mean +/- SD), with 15 of the patients being obese of android distribution (BMI > 30 kg/m2 and waist-to-hip ratio > 0.8). In addition, there were 15 android obese nondiabetic subjects and 10 healthy subjects serving as the control group. RESULTS: All groups of patients in this study (diabetic, obese, and obese diabetic) showed significantly higher levels of Lp(a) than the healthy control group. Lp(a) concentrations were significantly higher in NIDDM patients with android type of obesity than in nondiabetic androids (24.1 +/- 5.6 vs. 14.8 +/- 2.4 mg/dl, P < 0.001). Significantly greater levels of Lp(a) were found in nonobese subjects with diabetes when compared with obese subjects without diabetes (22.3 +/- 4.1 vs. 14.8 +/- 2.4 mg/dl, P < 0.001). Furthermore, Lp(a) serum concentrations were not dependent on the degree of glycemic control (controlled NIDDM 23.6 +/- 5.0 vs. uncontrolled NIDDM 21.4 +/- 2.7 mg/dl, NS), but were much greater in subjects with diabetes complicated by vascular disease (complicated 26.3 +/- 5.0 vs. uncomplicated 20.5 +/- 2.7 mg/dl, P < 0.001). No correlation was found between Lp(a) and other lipid parameters in this study. CONCLUSIONS: Lp(a) levels are significantly elevated in both android-obese and nonobese NIDDM patients regardless of the degree of glycemic control. Lp(a) is an independent risk factor showing greater elevations in those subjects complicated with diabetic vascular diseases.  相似文献   

12.
The study aim was to assess the relationship between homocyst(e)inemia and microalbuminuria in non-insulin-dependent diabetes mellitus (NIDDM) patients. The study was performed on 33 NIDDM patients (16 males and 17 females), and 16 healthy control subjects (seven males and nine females). Plasma fasting and post-methionine load homocyst(e)ine (tHcy), together with other parameters that could modify tHcy levels, were assessed. There were no significant differences between NIDDM patients and controls for fasting tHcy (8.12 +/- 3.17 v 7.19 +/- 2.40 micromol/L) and post-methionine load tHcy (26.51 +/- 11.50 v 25.06 +/- 10.76 micromol/L). Moreover, there was a significant correlation between urinary albumin excretion (UAE) and fasting tHcy (r = .340, P = .05) and post-methionine load tHcy (r = .502, P = .004) in NIDDM patients. Fasting tHcy was correlated both with post-methionine load tHcy (r = .429, P = .01) and with vitamin B12 (r = -.349, P = .04) in NIDDM patients. Microalbuminuric NIDDM patients had higher fasting tHcy (9.05 +/- 3.83 micromol/L) than normoalbuminurics (7.12 +/- 1.95 micromol/L). In addition, NIDDM patients with complications presented higher fasting tHcy values than the group without complications (9.61 +/- 3.34 v 6.53 +/- 2.09 micromol/L, Kolmogorov-Smirnov two-sample test for nonparametric data [KS] = 1.794, P = .003), without any other significant differences in the parameters considered. tHcy could be an important risk factor worsening the prognosis in NIDDM patients, especially microalbuminuric patients. Microalbuminuric NIDDM patients could be particularly prone to hyperhomocyst(e)inemia, probably due to endothelial or renal dysfunction with a reduction in the scavenging of tHcy.  相似文献   

13.
Knowledge about body composition is important in metabolic and nutritional studies. In this cross-sectional study the body composition of 403 healthy white Dutch children and adolescents was evaluated by using dual-energy X-ray absorptiometry (DXA). Possible determinants of body composition were analyzed. In 85 subjects the results of bioelectrical impedance analysis (BIA) were compared with DXA. Fat mass, lean tissue mass, and bone mineral content were greater in older boys and girls. Percentage body fat was greater in older girls but not in boys and it was higher in girls than in boys at all ages. From the age of 14 y boys had higher lean tissue mass and bone mineral content than girls. Tanner stage had a significant relation with body composition in both sexes. Percentage body fat was lower in boys in stage 4 than in stage 3 and was higher in consecutive Tanner stages in girls. After adjustment for age, Tanner stage was significantly positively related to lean tissue mass and bone mineral content in boys and girls and to percentage body fat and fat mass in girls. The profession of the parents and the education of the father had a significant negative correlation with percentage body fat and fat mass in girls (P < 0.01). Physical activity was related to lean tissue mass (P = 0.001) but not to fat mass in boys after adjustment for age. A high correlation and a small difference was found between lean body mass by BIA and lean tissue mass by DXA. Body composition in healthy Dutch children and adolescents is related to age, sex, Tanner stage, socioeconomic status, and physical activity.  相似文献   

14.
OBJECTIVES: To determine (1) the prevalence of hypokalemia (plasma potassium < or = 3.4 mmol/L) in a group of stroke patients in comparison with age- and sex-matched groups of patients having sustained a myocardial infarction or having mild hypertension and (2) the association between plasma potassium concentration and stroke outcome. DESIGN: Observational study. PARTICIPANTS: A total of 421 consecutive stroke patients admitted to a teaching hospital, 150 consecutive patients 50 years or older with myocardial infarction admitted to the hospitals Coronary Care Unit, and 161 out-patients 60 years or older with borderline and established hypertension. MEASUREMENTS: All stroke and cardiac patients had plasma urea and electrolytes estimated within 2 hours of hospital admission; in the hypertensive group blood samples were taken in clinic. Stroke patients had blood pressure, stroke severity (Barthel score) and smoking status recorded. A sub-group of 61 stroke patients and all 79 hypertensive patients not taking antihypertensive medication had 24-hour urine electrolyte excretion measured. Outcome (independent, dependent, or dead) at 3 months post-stroke was established in 349 patients. RESULTS: Hypokalemia occurred more frequently in stroke patients than in patients with myocardial infarction (84 (20%) vs 15 (10%), P = .008) or patients with hypertension (84 (20%) vs 13 (8%), P < .001), even when patients taking diuretics were excluded from analysis (56 (19%) vs 12 (9%) of cardiac group, P = .014 and 56 (19%) vs 4 (5%) of hypertensive group, P = .005, respectively). 24-hour urine excretion of potassium and the potassium:creatinine ratio was lower in stroke patients than in hypertensive patients (41 +/- 21 vs 62 +/- 25 mmol/24 hour, P = .001, 5.5 +/- 2.2 vs 7.4 +/- 2.6 mmol/24 hour, P = .001, respectively). On survival analysis, a lower plasma potassium on admission to hospital was associated with an increased chance of death, independent of age, stroke severity, history of hypertension, blood pressure level, or smoking history (hazard ratio 1.73 (95% CI: 1.03-2.9) for a 1 mmol/L lower plasma potassium concentration). CONCLUSIONS: Hypokalemia post stroke is common and may be associated with a poor outcome.  相似文献   

15.
OBJECTIVE: To determine the overall effect of paraplegia and pressure sores on resting metabolic rate. DESIGN: Unblinded, case-control study using a convenience sample. SETTING: Hospital primary care setting. PATIENTS: Fourteen individuals with paraplegia and pressure sores (PS-Para), 24 with paraplegia in good health (NPS-Para), and 23 non-spinal cord injury (SCI) controls. MAIN OUTCOME MEASURES: The planned outcome measures consisted of resting metabolic rate, percent of predicted resting metabolic rate, resting metabolic rate per kilogram body weight, and resting metabolic rate per meter squared body surface area. Post hoc analyses were used to identify the effect of completeness of lesion, smoking, and pressure sores on percent of predicted resting metabolic rate and resting metabolic rate per kilogram body weight. RESULTS: Percent of predicted resting metabolic rate and resting metabolic rate per kilogram body weight were significantly higher in the PS-Para group than in the NPS-Para or control groups (115% +/- 4% vs 100% +/- 2% or 107% +/- 2%, p < .05) and (25.9 +/- 1.2 vs 21.4 +/- 0.6 or 22.5 +/- 0.4 kcal/kg, p < .05, respectively). The resting metabolic rate per meter squared body surface area was significantly higher in the PS-Para group than in NPS-Para group (973 +/- 39 vs 874 +/- 20kcal/m2, p < .05). In the PS-Para group, current smokers had significantly higher resting metabolic rate per kilogram body weight than nonsmokers (27.3 +/- 1.7 vs 24.0 +/- 1.4kcal/kg, p < .01). Controlling for the effects of smoking in a multiple regression model, those in the PS-Para group had significantly (p < .001) greater percent of predicted resting metabolic rate and resting metabolic rate per kilogram body weight than those in the NPS-Para group. CONCLUSIONS: These findings indicate that individuals with SCI may have a decreased percent of predicted resting metabolic rate and those with pressure sores may have a hypermetabolic state. This hypermetabolic state is significantly higher than that resulting from smoking. Because ordinary prediction equations for energy expenditure may not be accurate when applied to subjects with paraplegia and pressure sores, quantification of energy needs by indirect calorimetry is recommended.  相似文献   

16.
We examined the relationships among gender, sexual maturation, four-compartment model estimates of body composition, body fat distribution (magnetic resonance imaging for abdominal visceral fat and anthropometrics), aerobic fitness, basal and total energy expenditure, and overnight GH release in an ultrasensitive chemiluminescence assay in healthy prepubertal and pubertal boys (n = 18 and 11, respectively) and girls (n = 12 and 18, respectively). Blood samples were withdrawn every 10 min from 1800-0600 h to determine the area under the serum GH-time curve (AUC), sum of the GH peak heights (sigma GH peak heights), and the mean nadir GH concentration. GH release was greater in the pubertal than prepubertal subjects due to an increase in sigma GH peak heights (43.8 +/- 3.6 vs. 24.1 +/- 3.5 ng.mL-1, P = 0.0002) and mean nadir (1.7 +/- 0.2 vs. 0.7 +/- 0.2 ng.mL-1, P = 0.0002), but not peak number (4.3 +/- 0.2 vs. 4.5 +/- 0.2). The girls had a greater sigma GH peak heights (39.0 +/- 3.5 vs. 28.8 +/- 3.6 ng.mL-1, P = 0.05) and mean nadir concentration (1.4 +/- 0.2 vs. 0.9 +/- 0.2 ng.mL-1, P = 0.05) than the boys. Significant inverse relationships existed between sigma GH peak heights (r = -0.35, P = 0.06) or mean nadir (r = -0.39, P = 0.04) and four-compartment percent body fat for all boys but not for all girls or when combining all subjects. For all girls, significant inverse relationships existed between sigma GH peak heights (r = -0.39, P = 0.03) or mean nadir (r = -0.37, P = 0.04) and waist/hip ratio. Similar inverse relationships in all boys or all subjects were not significant. Forward stepwise regression analysis determined that bone age (i.e. maturation, primary factor) and gender were the significant predictors of AUC, sigma GH peak heights, and mean nadir. The influence of maturation reflects rising sex steroid concentrations, and the gender differences appear to be because of differences in estradiol concentrations rather than to body composition or body fat distribution.  相似文献   

17.
OBJECTIVE: To compare the effects on body composition and body weight of tibolone vs two different sequential oral or transdermal oestrogen-progestogen hormone replacement therapies versus no therapy. PATIENTS AND METHODS: One hundred postmenopausal women were assigned to a control group (n = 26), or randomized to 1) tibolone (TIB) 2.5 mg/day (n = 28), 2) oral oestradiol 2 mg/day (PO) plus sequential dydrogesterone 10 mg/day for 14 of 28 days per cycle (n = 26), or 3) transdermal oestradiol patch (TTS) releasing 50 micrograms/day plus oral sequential dydrogesterone 10 mg/day for 14 of 28 days per cycle (n = 20). Body composition was measured at the base-line and every 6 months for 2 years by DXA (Hologic QDR 1000 W). RESULTS: Total body fat mass increased (P < 0.05) in controls (+3.6 +/- 1.5%) and in TTS treated (+4.7 +/- 2.2%), but not in PO (-1.2 +/- 2.4%) and TIB (-1.6 +/- 2.2%) treated subjects. This increase in total fat mass in controls and TTS treated women was mostly due to an increase in fat mass of the trunk (P < 0.05), but not legs. As a result, a redistribution of body fat to the trunk occurred in controls, TTS and TIB, but not in PO treated women (P < 0.05). Total lean body mass decreased (P < 0.02) in controls (-1.7 +/- 0.7%) and PO (-1.4 +/- 0.6%) but not in TTS (+0.3 +/- 0.8%) and TIB (+0.4 +/- 0.5%) treated subjects. CONCLUSIONS: The menopause is associated with an increase in total body fat and a decline in lean body mass. Oral oestradiol/dydrogesterone and tibolone prevent total body fat changes, whereas transdermal oestradiol/oral dydrogesterone and tibolone prevent the lean mass changes. Furthermore, oral oestradiol/dydrogesterone prevents the shift to a central, android fat distribution.  相似文献   

18.
The bicarbonate-urea method for measuring CO2 production was applied to eight free-living patients (mean age, 68 +/- 10 years; mean weight, 69 +/- 10 kg; mean height, 1.65 +/- 0.10 m) with unresectable small-cell lung cancer for a period of 1 day (n = 5) or 2 days (n = 3). The basal metabolic rate (BMR) was measured in all subjects. The technique was first validated against whole-body indirect calorimetry over an additional 24-hour period in five of these subjects. The bicarbonate-urea method predicted net CO2 production to be 102.1% +/- 3.4% of that measured by whole-body indirect calorimetry, and energy expenditure, 101.5% +/- 3.8% of the measured calorimeter value (8.1 +/- 1.6 MJ/d). The 24-hour recovery of label in CO2 excreted by the body was 95.6% +/- 0.5%. In free-living conditions, the bicarbonate-urea method predicted energy expenditure to be 9.0 +/- 2.6 MJ/d. BMR was elevated by a mean of 6% (P < .05) compared with the Schofield standards. The physical activity level ([PAL] the ratio of total energy expenditure [TEE] to BMR) was variable (1.15 to 1.87), but the mean value was only 1.36 +/- 0.22, considerably less than that of moderately active healthy subjects with estimated PAL values of 1.55 (P < .05) to 1.65 (P < .01) and the mean results obtained by doubly labeled water (previous studies) in healthy age- and sex-matched subjects. This is the first time a tracer method for measuring CO2 production and energy expenditure has been validated against whole-body 24-hour indirect calorimetry in patients with lung cancer or a systemic inflammatory reaction. The agreement between the two methods is similar to that observed in normal subjects. This is also the first time a tracer method has been used to measure energy expenditure in free-living patients with lung cancer. The results suggest that TEE and the energy requirements necessary to maintain energy balance were not increased despite basal hypermetabolism, because of the associated decrease in physical activity.  相似文献   

19.
Spontaneously diabetic C57BL/6J obob and C57BL/Ks dbdb mice have been shown to have significantly decreased immunoassayable pancreatic somatostatin concentrations compared to lean littermate controls at 11-12 weeks: obob 1.06+/-0.15 pg/mug protein (n=10) vs control 1.94+/-0.-6 pg/mug protein (n=10) (mean +/- SE; p less than 0.005); dbdb 0.7+/-0.2 pg/mug protein (n=8) vs control 1.5+/-0.2 pg/mug protein (n=8) (mean +/- SE; p less than 0.005). An inverse relationship between circulating insulin levels and pancreatic SRIF concentration is suggested.  相似文献   

20.
1. To test whether cystic fibrosis (CF) altered the kinetics and dynamics of oral salbutamol, 11 patients with CF (19-33 years old; five females; FEV1: 37 +/- 12% of predicted value) and 10 healthy volunteers (20-41 years old; five females; FEV1: 99 +/- 14% of predicted value) received orally 4 mg salbutamol. 2. The estimated pharmacokinetic parameters of salbutamol in patients with CF were identical to those in healthy subjects. For instance, peak plasma concentrations of salbutamol were 10.5 +/- 2.6 (mean +/- s.d.) and 10.2 +/- 2.9 ng ml-1 (NS), and the area under salbutamol plasma concentrations as a function of time (AUC (0, 7 h)) was 43.0 +/- 9.3 ng ml-1 h and 43.3 +/- 12.7 ng ml-1 h (NS) in CF patients and in healthy subjects, respectively. Since on a mg kg-1 dose basis, CF patients received a dose 28% greater than healthy subjects, this lack of differences implies a decrease in the amount of salbutamol absorbed, or alternatively, an increase in both clearance and volume of distribution of salbutamol. 3. Salbutamol did not elicit bronchodilation in CF patients, but increased heart rate from 77 +/- 2 to 103 +/- 3 beats min-1 (P < 0.05). 4. Salbutamol decreased plasma potassium concentrations from 4.5 +/- 0.1 to 3.8 +/- 0.1 mmol l-1 in the CF group (P < 0.05) and from 4.1 +/- 0.2 to 3.4 +/- 0.1 mmol l-1 in the controls (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

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