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1.
《Endocrine practice》2015,21(9):1001-1009
Objective: Transsphenoidal adenomectomy (TSA) is first-line treatment for acromegaly. Our aim was to determine the impact of pre-operative biochemical parameters on the outcomes of surgery.Methods: Retrospective case series of 79 consecutive acromegalics operated between 1994 and 2013. Inclusion criteria were: first TSA, pathology-confirmed growth hormone (GH) adenoma, and follow-up >3 months. Biochemical remission was defined as normal insulin-like growth factor 1 (IGF-1) without adjuvant therapy during follow-up.Results: Median follow-up was 35.4 months (range, 3 to 187 months). Logistic regression analysis showed that the best model to predict long-term remission included the following pre-operative markers: GH, tumor diameter, and cavernous sinus invasion (CSI) (area under the curve, 0.933). A threshold GH of 40 ng/mL was associated with long-term remission (sensitivity, 97%; specificity, 42%). Group A (GH >40 ng/mL) comprised 19 patients (9 men); age, 43 ± 13 years; tumor diameter, 2.7 ± 1.0 cm; 73.7% with CSI; and pre-operative median GH, 77.8 ng/mL (interquartile range [IQR], 66.7 to 107.0 ng/mL). Three patients (15%) in group A achieved remission at 3 months, but 2 patients recurred during follow-up. Group B (GH ≤40 ng/mL) comprised 60 patients (25 men); age, 47 ± 13 years; tumor diameter, 1.6 ± 1.0 cm; 35% with CSI, preoperative median GH, 6.9 ng/mL (IQR, 3.4 to 16.9 ng/mL). Thirty-five patients (58%) in group B achieved remission at 3 months without recurrence during follow-up. Group A had larger tumors and a higher proportion of tumors with CSI (P<.05).Conclusion: Both GH and IGF-1 should be measured pre-operatively, as highly elevated GH levels negatively impact long-term surgical remission. This strategy allows early identification of patients who require adjuvant therapy and may decrease time to biochemical control.Abbreviations: AUC = area under the curve CSI = cavernous sinus invasion GH = growth hormone ICA = internal carotid artery IGF-1 = insulin-like growth factor 1 MRI = magnetic resonance imaging OGTT = oral glucose tolerance test POD2 = postoperative day 2 TSA = transsphenoidal adenomectomy 相似文献
2.
Chris Hyunchul Jo Pil Whan Yoon Hyang Kim Kyung Sun Kang Kang Sup Yoon 《Cell and tissue research》2013,353(1):41-52
Mesenchymal stem cells (MSCs) can be obtained from various sources. MSCs from different origins appear to have different preferences for differentiation. In this study, we have compared the in vivo osteogenic potential of adult MSCs from adipose tissue (AT) and bone marrow (BM) with fetal MSCs from umbilical cord (UC) and umbilical cord blood (UCB) by using a rat critical-sized femoral defect model. We have also sought to determine whether pretreatment with an osteogenic medium promotes osteogenesis in MSCs. Study groups were divided as follows: (1) defect only, (2) scaffold only, (3) AT MSCs in scaffolds, (4) BM MSCs in scaffolds, (5) UC MSCs in scaffolds and (6) UCB MSCs in scaffolds. Groups with MSCs were further divided with respect to their pretreatment. At 12 weeks after surgery, in vivo osteogenesis was measured radiographically and by micro-computed tomography (CT). Based on quantitative assessment by micro-CT, no significant difference of the mean bone volume fraction value (BV/TV) was seen between adult MSCs (AT and BM MSCs) and fetal MSCs (UC and UCB MSCs). The mean BV/TVs were significantly higher in non-pretreated BM MSC (14.2±1.4%) and UCB MSC (14.0±1.2%) and pretreated UC MSC (14.8±2.0%) than in those with the scaffold only (11.3±1.3%; P<0.05). In addition, AT (from 10.4±1.2% to 13.1±2.2%) and UC (from 10.3±0.7% to 14.8±2.0%) MSCs from solid tissues showed a significant increase in the mean BV/TV with pretreatment (P<0.05). In contrast, BM MSC (from 14.2±1.4% to 10.9±1.2%) and UCB MSC (from 14.0±1.2% to 11.6±1.0%) from non-solid tissues showed a significant decrease with pretreatment (P<0.05). 相似文献
3.
Valera Mora ME Manco M Capristo E Guidone C Iaconelli A Gniuli D Rosa G Calvani M Mingrone G 《Obesity (Silver Spring, Md.)》2007,15(8):2012-2018
Objective: The objective was to evaluate ghrelin and growth hormone (GH) interactions and responses to a growth hormone‐releasing hormone (GHRH)/arginine test in severe obesity before and after surgically‐induced weight loss. Research Methods and Procedures: Our study population included 11 severely obese women 39 ± 12 years of age, with a mean BMI of 48.6 ± 2.4 kg/m2, re‐studied in a phase of stabilized body weight, with a BMI of 33.4 ± 1.2 kg/m2, 18 months after having successfully undergone biliopancreatic diversion (BPD). A GHRH/arginine test was performed before and 18 months after BPD to evaluate ghrelin and GH interactions. Active ghrelin, measured by radioimmunoassay (RIA), and GH, measured by chemiluminescence assay, were assayed before and after the GHRH/arginine test. Results: Fasting serum GH levels and GH area under the curve (AUC) significantly increased from 0.2 ± 0.05 ng/mL to 1 ± 0.3 ng/mL (p < 0.05) and from 514.76 ± 98.7 ng/mL for 120 minutes to 1957.3 ± 665.1 ng/mL for 120 minutes after bariatric surgery (p < 0.05), respectively. Although no significant change in fasting ghrelin levels was observed (573 ± 77.9 before BPD vs. 574.1 ± 32.7 after BPD), ghrelin AUC significantly increased from ?3253.9 ± 2180.9 pg/mL for 120 minutes to 1142.3 ± 916.4 pg/mL for 120 minutes after BPD (p < 0.05). Fasting serum insulin‐like growth factor (IGF)‐1 concentration did not change significantly (133.6 ± 9.9 ng/mL before vs. 153.3 ± 25.2 ng/mL after BPD). Discussion: Our study demonstrates that the mechanisms involved in ghrelin and GH secretion after the secretagogue stimulus (GHRH/arginine) are consistent with patterns observed in other populations. 相似文献
4.
Growth hormone (GH) and 3-methoxy-4-hydroxyphenelethylene glycol (MHPG) response was measured hourly for 4 hours in 8 children with Attention Deficit Disorder with Hyperactivity (ADD+H) following an acute single-dose of clonidine. The clonidine challenge was repeated before, during, and one day after 12 weeks of treatment with methylphenidate (MPH). Before MPH treatment, the plasma growth hormone (GH) rose to 31.3 ± 4.6 (Mean ± SE) ng/ml; during MPH treatment, the GH peak was only 14.8 ± 3.2 ng/ml; one day after discontinuation of MPH, GH rose to only 20.8 ± 3.9 ng/ml. MHPG release was inhibited by clonidine in all treatment conditions but tended to be more decreased during MPH treatment. Some children with ADD+H may have hypersensitivity of the post-synaptic alpha-1 noradrenergic receptor which is diminished by MPH treatment. The extent to which these effects are pharmacological or represent a change in receptor sensitivity requires further study. 相似文献
5.
Wang Yu-hong Lin Yuan Xue Ling Wang Jin-hui Chen Min-hu Chen Jie 《BMC endocrine disorders》2012,12(1):1-9
In addition to stimulating linear growth in children, growth hormone (GH) influences metabolism and body composition. These effects should be considered when individualizing GH treatment as dose-dependent changes in metabolic markers have been reported. Hypothesis: There are different dose-dependent thresholds for metabolic effects in response to GH treatment. A randomized, prospective, multicentre trial TRN 98-0198-003 was performed for a 2-year catch-up growth period, with two treatment regimens (a) individualized GH dose including six different dose groups ranging from 17–100 μg/kg/day (n=87) and (b) fixed GH dose of 43 μg/kg/day (n=41). The individualized GH dose group was used for finding dose–response effects, where the effective GH dose (ED 50%) required to achieve 50% Δ effect was calculated with piecewise linear regressions. Different thresholds for the GH dose were found for the metabolic effects. The GH dose to achieve half of a given effect (ED 50%, with 90% confidence interval) was calculated as 33(±24.4) μg/kg/day for Δ left ventricular diastolic diameter (cm), 39(±24.5) μg/kg/day for Δ alkaline phosphatase (μkat/L), 47(±43.5) μg/kg/day for Δ lean soft tissue (SDS), 48(±35.7) μg/kg/day for Δ insulin (mU/L), 51(±47.6) μg/kg/day for Δ height (SDS), and 57(±52.7) μg/kg/day for Δ insulin-like growth factor I (IGF-I) SDS. Even though lipolysis was seen in all subjects, there was no dose–response effect for Δ fat mass (SDS) or Δ leptin ng/ml in the dose range studied. None of the metabolic effects presented here were related to the dose selection procedure in the trial. Dose-dependent thresholds were observed for different GH effects, with cardiac tissue being the most responsive and level of IGF-I the least responsive. The level of insulin was more responsive than that of IGF-I, with the threshold effect for height in the interval between. 相似文献
6.
为探究不同食物及食物密度对盐蚕豆虫(Fabrea salina)种群动力学的影响。本文采用商业酵母和杜氏藻(Dunaliella salina)两种不同类型的饲料喂食盐蚕豆虫,探究其种群动力学特征。结果表明,杜氏藻组的盐蚕豆虫具有较高的生长率[(0.78 ± 0.019)/d]、较低的世代时间[(0.89 ± 0.021)d],内禀生长率为1.49/d,米氏常数值为1 121.32;商业酵母组生长率较低[(0.36 ± 0.001)/d],世代时间较长[(1.93 ± 0.007)d],内禀生长率为0.51/d,米氏常数值为2.68。One-way ANOVA检验结果表明,食物及食物密度对盐蚕豆虫的种群生长均有极显著影响(P < 0.01)。以密度为10 × 109 cells/L的杜氏藻投喂,可在短时间内实现盐蚕豆虫的高密度培养和利用,而酵母适用于实验室中盐蚕豆虫的保种工作。 相似文献
7.
Jens J. Christiansen Nina Vahl Sanne Fisker Niels Mller Jens S. Christiansen Jens O.L. Jrgensen 《Obesity (Silver Spring, Md.)》2002,10(4):284-290
Objective: To investigate the impact of age on the association between the respiratory quotient (RQ) and growth‐hormone (GH) secretion and to investigate the acute lipolytic response to an exogenous GH bolus. Research Methods and Procedures: A cross‐sectional study of 36 non‐obese healthy subjects (18 women and 18 men) from two age groups was used: “younger” (mean age, 29.5 years; range, 27 to 34 years) and “older” (mean age, 50.8 years; range, 47 to 59 years). Endogenous GH secretion by means of deconvolution analysis of 24‐hour serum GH concentrations was measured every 20 minutes. Resting RQ was measured after a 12‐hour overnight fast. The lipolytic response to an intravenous exogenous GH bolus (200 μg) was assessed by measuring serum levels of free fatty acids as well as changes in RQ. Additional measurements included body composition (regional computed tomography scan and DXA) and physical fitness (Vo 2max). Results: Resting RQ did not differ between the two age groups: 0.81 ± 0.01 (young) vs. 0.82 ± 0.01 (older; not significant). Several estimates of GH release correlated positively with RQ in the younger group, whereas a negative correlation was detected in the older subjects [GH production rate (μg/liter × kg) vs. RQ: r = 0.62, p < 0.01 (younger); r = ?0.53; p = 0.02 (older)]. By regression analysis, 52% to 58% of the variation in RQ could be explained by GH status. After an exogenous GH bolus, the incremental response in nonesterified fatty acid was slightly higher in younger individuals (p = 0.09). Discussion: Resting RQ is significantly correlated with GH status. This association is positive in younger individuals and negative in older individuals. The lipolytic response to exogenous GH is moderately higher in younger compared with older individuals. GH status should be taken into account when investigating the residual variation in RQ. 相似文献
8.
This study explores the effect of microbial consortium composition and reactor configuration on methyl tert-butyl ether (MTBE) biodegradation in the presence of benzene, toluene, ethylbenzene and p-xylenes(BTEX). MTBE biodegradation was monitored in the presence and absence of BTEX in duplicate batch reactors inoculated
with distinct enrichment cultures: MTBE only (MO—originally enriched on MTBE) and/or MTBE BTEX (MB—originally enriched on
MTBE and BTEX). The MO culture was also applied in a semi-batch reactor which received both MTBE and BTEX periodically in
fresh medium after allowing cells to settle. The composition of the microbial consortia was explored using a combination of
16S rRNA gene cloning and quantitative polymerase chain reaction targeting the known MTBE-degrading strain PM1T. MTBE biodegradation was completely inhibited by BTEX in the batch reactors inoculated with the MB culture, and severely
retarded in those inoculated with the MO culture (0.18 ± 0.04 mg/L-day). In the semi-batch reactor, however, the MTBE biodegradation
rate in the presence of BTEX was almost three times as high as in the batch reactors (0.48 ± 0.2 mg/L-day), but still slower
than MTBE biodegradation in the absence of BTEX in the MO-inoculated batch reactors (1.47 ± 0.47 mg/L-day). A long lag phase
in MTBE biodegradation was observed in batch reactors inoculated with the MB culture (20 days), but the ultimate rate was
comparable to the MO culture (0.95 ± 0.44 mg/L-day). Analysis of the cultures revealed that strain PM1T concentrations were lower in cultures that successfully biodegraded MTBE in the presence of BTEX. Also, other MTBE degraders,
such as Leptothrix sp. and Hydrogenophaga sp. were found in these cultures. These results demonstrate that MTBE bioremediation in the presence of BTEX is feasible,
and that culture composition and reactor configuration are key factors. 相似文献
9.
Michael D Kennedy Mark J Haykowsky Carol A Boliek Ben TA Esch Jessica M Scott Darren ER Warburton 《Dynamic medicine : DM》2006,5(1):8
Background
Near infrared spectroscopy (NIRS) is used to assess muscle oxygenation (MO) within skeletal muscle at rest and during aerobic exercise. Previous investigations have used a single probe placement to measure MO during various forms of exercise. However, regional MO differences have been shown to exist within the same muscle which suggests that different areas of the same muscle may have divergent MO. Thus, the aim of this study was to examine whether regional differences in MO exist within the same muscle during different types of incremental (rest, 25, 50, 75, 100 % of maximum) exercise (1 leg knee extension (KE), 2 leg KE, or cycling).Methods
Nineteen healthy active males (Mean ± SD: Age 27 ± 4 yrs; VO2max: 55 ± 11 mL/kg/min) performed incremental exercise to fatigue using each mode of exercise. NIRS probes were placed on the distal and proximal portion of right leg vastus lateralis (VL). Results were analyzed with a 3-way mixed model ANOVA (probe × intensity × mode).Results
Differences in MO exist within the VL for each mode of exercise, however these differences were not consistent for each level of intensity. Comparison of MO revealed that the distal region of VL was significantly lower throughout KE exercise (1 leg KE proximal MO – distal MO = 9.9 %; 2 leg KE proximal MO – distal MO = 13 %). In contrast, the difference in MO between proximal and distal regions of VL was smaller in cycling and was not significantly different at heavy workloads (75 and 100 % of maximum).Conclusion
MO is different within the same muscle and the pattern of the difference will change depending on the mode and intensity of exercise. Future investigations should limit conclusions on MO to the area under assessment as well as the type and intensity of exercise employed.10.
《Archives of animal nutrition》2013,67(5):372-384
An improved understanding of the role of forage quality on the processes of particle dynamics and turnover is important for the development of healthier and cost-effective feeding strategies that aim at lowering the proportions of concentrates in the diets of cattle. The aim of this study was to evaluate the effects of feeding hays of different qualities on particle dynamics, digestion kinetics and turnover in the gastrointestinal tract (GIT). Three non-lactating, rumen fistulated Holstein cows were fed diets consisting exclusively of hay with either low quality [Group LH; 605 ± 12.4 g/kg neutral detergent fibre (NDF) and 63 ± 4.7 g/kg crude protein (CP)] or good quality (Group GH; 551 ± 20.1 g/kg NDF and 116 ± 3.6 g/kg CP). Data showed that in situ dry matter (DM) disappearance of the soluble fraction was greater for Group GH (p < 0.05). Feeding good quality hay also lowered the proportion of particles >1.18 mm particularly during the eating process (p < 0.05). Changes in the particle size occurring afterwards were greater for Group GH as well (p < 0.05); approximately 30% in the comminution in the particle size occurred postruminally. Feeding hay of good quality lowered DM content of solid rumen digesta (p < 0.05), accelerated (p < 0.05) the turnover rate of DM and NDF in the GIT and increased DM intake (p < 0.05). In conclusion, feeding forages of better quality significantly promoted degradation processes and kinetics in the GIT with positive effects on turnover rate of digesta and feed intake in Holstein cows. 相似文献
11.
Serés L Lopez-Ayerbe J Coll R Rodriguez O Vila J Formiguera X Alastrue A Rull M Valle V 《Obesity (Silver Spring, Md.)》2006,14(2):273-279
Objective: To investigate the effects of surgically induced weight loss on exercise capacity in patients with morbid obesity (MO). Research Methods and Procedures: A prospective 1‐year follow‐up study was carried out, with patients being their own controls. A symptom‐limited cardiopulmonary exercise stress test was performed in 31 MO patients (BMI > 40 kg/m2) before and 1 year after undergoing bariatric surgery. Results: At 1 year after surgery, weight was reduced from 146 ± 33 to 95 ± 19 kg (p < 0.001), and BMI went from 51 ± 4 to 33 ± 6 kg/m2 (p < 0.001). After weight loss, obese patients performed each workload with lower oxygen consumption, heart rate, systolic arterial pressure, and ventilatory volume (p < 0.001). This reduced energy expenditure allowed them to increase the duration of their effort test from 13.8 ± 3.8 to 21 ± 4.2 minutes (p < 0.001). Upon finishing the exercise, MO patients before surgery were able to reach only 83% of their age‐predicted maximal heart rate, and their respiratory exchange ratio was 0.87 ± 0.06. After weight loss, those values were 90% and 1 ± 0.08, respectively (p < 0.01). When we compared the peak O2 pulse corrected by fat free mass before and after surgery, no significant differences between the groups were found. Discussion: After surgically induced weight loss, MO patients markedly improved their exercise capacity. This is due to the fact that they were able to perform the external work with lower energy expenditure and also to increase cardiovascular stress, optimizing the use of cardiac reserve. There were no differences in cardiac function before and after surgery. 相似文献
12.
Since interactions between progesterone (P4), Cortisol (F), cortisone (E) and corticosteroid binding globulin (CBG) may influence the metabolic clearance rates (MCR) of these steroids, the effect of altering circulating F concentrations on clearance of the steroids was determined. MCR of P4, F and E were determined by the iv constant infusion method in 6 pregnant and 6 nonpregnant baboons (Papio papio). Serum F concentrations were altered by iv infusion of 5 mg F/90 min or im injection of betamethasone (3 mg bi-daily for 2 days). Mean MCR-P4 (1/d/kg ± SE) was greater (P < 0.01) in pregnant (92.8 ± 8.5) than in nonpregnant (53.9 ± 4.4) animals while mean MCR-F was similar in both groups (, respectively). Mean MCR-E was also similar in pregnant (30.8 ± 4.9) and nonpregnant (34.1 ± 4.5) baboons. Mean serum F concentrations (/gmg/100 ml ± SE) in 4 nonpregnant (42.0 ± 8.6) and 4 pregnant (52.2 ± 10.0) baboons were increased (P < 0.05) 60% by F administration but MCR-P4, -F and -E were unaltered. Betamethasone treatment reduced (P < 0.05) serum F 75% in both groups. In nonpregnant baboons, betamethasone treatment reduced (P < 0.01) MCR-P4 (37.3 ± 3.9), MCR-F (7.4 ± 1.6) and MCR-E (18.5 ± 3.7). Betamethasone treatment of pregnant animals reduced (P < 0.01) MCR-P4 (56.5 ± 7.4), MCR-F (6.3 ± 0.8) and MCR-E (14.6 ± 2.6). Infusion of F into betamethasone-treated animals increased serum F levels and increased MCR-P4, -F and -E. It is concluded that variations in serum F levels affect the clearance of F, E and P4 presumably because of the mutual interactions of these steroids with CBG. 相似文献
13.
Gerald R. Grimsley J. Martin Scholtz C. Nick Pace 《Protein science : a publication of the Protein Society》2009,18(1):247-251
We tabulated 541 measured pK values reported in the literature for the Asp, Glu, His, Cys, Tyr, and Lys side chains, and the C and N termini of 78 folded proteins. The majority of these values are for the Asp, Glu, and His side chains. The average pK values are Asp 3.5 ± 1.2 (139); Glu 4.2 ± 0.9 (153); His 6.6 ± 1.0 (131); Cys 6.8 ± 2.7 (25); Tyr 10.3 ± 1.2 (20); Lys 10.5 ± 1.1 (35); C‐terminus 3.3 ± 0.8 (22) and N‐terminus 7.7 ± 0.5 (16). We compare these results with the measured pK values of these groups in alanine pentapeptides, and comment on our overall findings. 相似文献
14.
Identification and Distribution of m- and p-Hydroxyphenylacetic Acids in the Brain of the Rat 总被引:1,自引:0,他引:1
The m and p isomers of hydroxyphenylacetic acid have been identified and quantitated in whole rat brain and in several regions using a capillary column high resolution gas chromatography–mass spectrometry procedure. Their concentrations were: for m-hydroxyphenylacetic acid (mean ± S.E., number of determinations in parentheses)—whole brain, 2.3 ± 0.3 ng/g (7); hypothalamus, 1.2 ± 0.3 ng/g (5); caudate nucleus, 5.5 ± 0.6 ng/g (5); brain stem, 1.8 ± 0.1 ngig (5); cerebellum, 1.2 ± 0.1 ng/g (5) and the “rest,” 1.7 ± 0.1 ng/g (5); and for p-hydroxyphenylacetic acid–whole brain, 10.6 ± 0.7 ng/g (7); hypothalamus, 4.5 ± 0.1 ng/g (4); caudate nucleus, 28.3 ±1.6 ng/g (5); brain stem, 8.6 ± 0.6 ng/g (5); cerebellum, 8.1 ± 0.4 ng/g (9, and the “rest,” 5.3 ± 0.5 ng/g (5). This heterogeneous distribution parallels closely that exhibited by their respective precursor amines, m- and p-tyramine. 相似文献
15.
A. Lafuente N. Márquez D. Pazo A. I. Esquifino 《Journal of physiology and biochemistry》2001,57(3):231-236
This paper analyzes possible dopamine (DA) mediated cadmium effects on plasma levels of prolactin, growing hormone (GH) and adrenocorticotropic hormone (ACTH), and if these changes are related to metal accumulation. For that purpose, adult male rats were treated with 50 mg/L of CdCl2 in the drinking water for one month. Plasma levels of prolactin, ACTH and GH were measured by specific double antibody radioimmunoassays. DA was measured by high performance liquid chromatography using electrochemical detection. Cadmium content in the tissues was measured by atomic absorption spectometry with graphite furnace. Analysis was performed by using a T-Student test. Metal exposure increased DA content (34.79±3.06vs. 18.2±2.88 pg/mg protein) and decreased its turnover (0.40±0.07vs. 0.75±0.06) in posterior hypothalamus. Cadmium also decreased DA turnover in median eminence (0.48±0.15vs. 1.50±0.63). Plasma levels of prolactin and GH decreased (2.4±0.11vs. 3.1±0.15 ng/mL and 5.37±0.05vs. 9.87±1.8 ng/mL respectively), while those of ACTH increased (2.73±0.14vs. 1.7±0.16 ng/mL). Cadmium concentration increased in both hypothalamus (4.88±0.34vs. 0.72±0.2 μg/g) and pituitary (22.82±4.57vs. 5.02±1.25 μg/g) after the metal exposure. These results suggest that cadmium effects on the secretion of these hormones are not mediated by dopamine and might be correlated to the metal accumulation at pituitary level. 相似文献
16.
Daily energy, protein, calcium (Ca), phosphorus (P), zinc (Zn), copper (Cu), manganese (Mn), and dietary fiber intakes of
East Indian Punjabi immigrants consuming predominantly lacto-ovo vegetarian diets [59 males (M), mean age 37.7±10.5 yr. and
53 females (F), mean age 33.3±7.4 yr] were assessed by calculation from 3-d weighted dietary records, using food composition
values and by chemical analysis of 30 1-d diet composites. Mean daily calculated intakes wer: energy, M=2374±713 and F=1708±552
kcal; protein, M=95.8±35.1 and F=68.0±28.9g; Ca, M=990±468 and F=837±393 mg; M=2034±778 and F=1489±551 mg; Zn, M=12.2±4.9
and F=8.8±3.9 mg; Cu, M=2.4±0.9 and F=1.7±0.6 mg; and Mn, M=7.7±3.3 and F=5.7±2.4 mg. The mean daily Ca intakes for M and
F were 124 and 105%, respectively, of the Canadian Recommended Nutrient Intake (RNI). In contrast, average P intakes were
much higher, 254 and 213% of the RNI for M and F, respectively, so that the mean Ca:P ratios were 1:2.0 for M and 1:1.8 for
F. Forty-eight percent of the F compared to 19% of the M had Zn intakes below the current RNI, whereas 28% of the M and 77%
of the F received Cu intakes below the suggested US safe and adequate range. Mean daily Mn intakes were higher than those
for subjects consuming omniverous North American diets and none of the subjects had Mn intakes below the US safe and adequate
range. 相似文献
17.
Plasma lactate, GH and GH-binding protein levels in exercise following BCAA supplementation in athletes 总被引:4,自引:0,他引:4
Summary. Branched chain amino acids (BCAA) stimulate protein synthesis, and growth hormone (GH) is a mediator in this process. A pre-exercise
BCAA ingestion increases muscle BCAA uptake and use. Therefore after one month of chronic BCAA treatment (0.2 g kg−1 of body weight), the effects of a pre-exercise oral supplementation of BCAA (9.64 g) on the plasma lactate (La) were examined
in triathletes, before and after 60 min of physical exercise (75% of VO2max). The plasma levels of GH (pGH) and of growth hormone binding protein (pGHBP) were also studied. The end-exercise La of
each athlete was higher than basal. Furthermore, after the chronic BCAA treatment, these end-exercise levels were lower than
before this treatment (8.6 ± 0.8 mmol L−1 after vs 12.8 ± 1.0 mmol L−1 before treatment; p < 0.05 [mean ± std. err.]). The end-exercise pGH of each athlete was higher than basal (p < 0.05). Furthermore,
after the chronic treatment, this end-exercise pGH was higher (but not significantly, p = 0.08) than before this treatment
(12.2 ± 2.0 ng mL−1 before vs 33.8 ± 13.6 ng mL−1 after treatment). The end-exercise pGHBP was higher than basal (p < 0.05); and after the BCAA chronic treatment, this end-exercise
pGHBP was 738 ± 85 pmol L−1 before vs 1691 ± 555 pmol L−1 after. pGH/pGHBP ratio was unchanged in each athlete and between the groups, but a tendency to increase was observed at end-exercise.
The lower La at the end of an intense muscular exercise may reflect an improvement of BCAA use, due to the BCAA chronic treatment.
The chronic BCAA effects on pGH and pGHBP might suggest an improvement of muscle activity through protein synthesis.
Received January 5, 1999 / Accepted June 17, 1999 相似文献
18.
Colette Fons Jean-Frédéric Brun Michelle Fussellier Geneviève Cassanas Lucette Bardet André Orsetti 《Biological trace element research》1992,32(1-3):399-404
A possible role for zinc deficiency in some cases of growth retardation in southern France was investigated. Control values
for zinc for 160 children (age=12.5±2.4 yr) are 0.85±0.22 mg/L (mean ±2 SD). Twenty-five children with low serum zinc values
(<0.63 mg/L) and 25 matched short children with normal serum zinc values (>0.63 mg/L) were studied. Children in the two groups
did not differ significantly in age, pubertal development, stature, and weight. For the 25 children whose serum values were
low, we found significantly lower values for bone age delay, growth velocity in mm/month, as well as the ratio between calculated
growth velocity and theoretical growth velocity for the bone age (so that zincemia was correlated to these parameters in the
whole sample of 50 subjects). Nevertheless, no significant difference could be found between the two groups for serum somatomedin
C, serum osteocalcin values, and GH responses to the GH stimulatory tests (exercise test, overnight sampling, insulin-induced
hypoglycemia, arginine test). Therefore, low serum zinc is associated with a retardation in both somatic growth and pubertal
maturation. 相似文献
19.
Leanne M. Redman Johannes D. Veldhuis Jennifer Rood Steven R. Smith Donald Williamson Eric Ravussin for the Pennington CALERIE Team 《Aging cell》2010,9(1):32-39
Lifespan in rodents is prolonged by caloric restriction (CR) and by mutations affecting the somatotropic axis. It is not known if CR can alter the age‐associated decline in growth hormone (GH), insulin‐like growth factor (IGF)‐1 and GH secretion. To evaluate the effect of CR on GH secretory dynamics; forty‐three young (36.8 ± 1.0 years), overweight (BMI 27.8 ± 0.7) men (n = 20) and women (n = 23) were randomized into four groups; control = 100% of energy requirements; CR = 25% caloric restriction; CR + EX = 12.5% CR + 12.5% increase in energy expenditure by structured exercise; LCD = low calorie diet until 15% weight reduction followed by weight maintenance. At baseline and after 6 months, body composition (DXA), abdominal visceral fat (CT) 11 h GH secretion (blood sampling every 10 min for 11 h; 21:00–08:00 hours) and deconvolution analysis were measured. After 6 months, weight (control: ?1 ± 1%, CR: ?10 ± 1%, CR + EX: ?10 ± 1%, LCD: ?14 ± 1%), fat mass (control: ?2 ± 3%, CR: ?24 ± 3%, CR + EX: ?25 ± 3%, LCD: ?31 ± 2%) and visceral fat (control: ?2 ± 4%, CR: ?28 ± 4%, CR + EX: ?27 ± 3%, LCD: ?36 ± 2%) were significantly (P < 0.001) reduced in the three intervention groups compared to control. Mean 11 h GH concentrations were not changed in CR or control but increased in CR + EX (P < 0.0001) and LCD (P < 0.0001) because of increased secretory burst mass (CR + EX: 34 ± 13%, LCD: 27 ± 22%, P < 0.05) and amplitude (CR + EX: 34 ± 14%, LCD: 30 ± 20%, P < 0.05) but not to changes in secretory burst frequency or GH half‐life. Fasting ghrelin was significantly increased from baseline in all three intervention groups; however, total IGF‐1 concentrations were increased only in CR + EX (10 ± 7%, P < 0.05) and LCD (19 ± 4%, P < 0.001). A 25% CR diet for 6 months does not change GH, GH secretion or IGF‐1 in nonobese men and women. 相似文献
20.
C L Levy H E Carlson J R Sowers R E Goodlett W W Tourtellotte J M Hershman 《Life sciences》1979,24(8):743-749
Growth hormone (GH) and prolactin (PRL) secretion was studied in twelve patients with Huntington's Disease, eight unaffected relatives, and twenty normal subjects in response to provocative and suppressive tests. Prolactin responses to TRH, chlorpromazine, L-DOPA, and apormorphine were similar in all groups with the exception of a slightly blunted PRL response to THR in the unaffected relatives. Although GH responses to L-DOPA were similar in all groups, patients with Hungtinton's Disease had nearly absent GH responses to apomorphine (mean peak GH = 1.4±0.4 (SE) ng/m1) compared to normal control subjects (mean peak GH = 28.9±8.6 ng/m1). These results, which are similar to some previously reported findings in drug-induced tardive dyskinesia, suggest an abnormality in dopamine-mediated GH secretion in Huntington's Disease. 相似文献