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BACKGROUND: Human growth hormone (hGH) is best known for influencing bone and muscle growth, as well as body composition, but the use of recombinant hGH is controversial. Amino acids are a potentially safer alternative; however, preliminary investigations of the effects of oral amino acids on hGH release have been inconclusive. Therefore, we tested the effects of a novel blend of amino acids optimized to increase hGH release. STUDY QUESTION: Does an investigational amino acid supplement affect hGH release? STUDY DESIGN: This was a randomized, placebo-controlled, double-blind, crossover study that included 16 (12 men, 4 women; age 32 ± 14 years; body mass index 26.4 ± 5.0 kg/m) healthy participants. All participants received both placebo and the amino acid supplement after an overnight fast and completed all study visits. Treatment order was randomized, and each treatment was separated by a 1-week washout period. MEASURES AND OUTCOMES: The primary outcomes were the percent change in hGH from baseline to 120 minutes and the area under the curve of hGH over baseline. Serum hGH was measured using enzyme-linked immunosorbent assay at baseline and 15, 30, 60, 90, and 120 minutes. RESULTS: At 120 minutes, hGH levels increased by 682% (8-fold) from baseline and were significantly higher than placebo (P = 0.01). In addition, a significantly higher mean area under the curve was observed for the amino acid supplement compared with the placebo [20.4 (95% confidence interval, 19.9-21.0 ng/mL) vs. 19.7 (95% confidence interval, 18.7-20.6 ng/mL); P = 0.04]. CONCLUSIONS: These results show that a single dose of the oral amino acid supplement was sufficient to significantly increase hGH levels in healthy adult men and women. CLINICAL TRIAL REGISTRY:: clinicaltrials.gov NCT01540773.
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Aminoácidos/farmacologia , Suplementos Nutricionais , Hormônio do Crescimento Humano/biossíntese , Adulto , Estudos Cross-Over , Método Duplo-Cego , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Introduction: An orally administered amino acid-based test supplement was recently shown to increase human growth hormone (hGH) in healthy adults. This prospective, observational, single-center, single-arm cohort study investigated the effects of 24 weeks of daily oral administration of the test supplement in individuals with stress-related weight gain, fibromyalgia (FM) and stress-related low-normal hGH production (15-30th percentile for age-appropriate levels) on insulin-like growth factor 1 (IGF-1), an indicator of hGH levels caused by stress related stimulation of somatostatin. Methods: Participants continued to receive standard care. The primary endpoint was the change from baseline to endpoint (Week 24) in serum IGF-1. Additional endpoints included the change in body weight, clinical symptoms (assessed with the Revised Fibromyalgia Impact Questionnaire [FIQR], range 0-100, and Perceived Stress Scale [PSS], range 0-40), fasting cardiometabolic markers, tolerability, and safety. The study enrolled 84 fibromyalgia patients with low-normal age-adjusted IGF-1 serum levels. High mean ± Standard Deviation (SD) baseline FIQR and PSS scores of 76 ± 16 and 32 ± 5, respectively, indicated poor to moderate symptom management with standard care. All individuals completed 24 weeks. Results: Serum IGF-1 levels increased with a Week 24 mean± Standard Error (SE) change of 28.4 ± 3.0 ng/mL (p<0.001). Body weight was reduced with a Week 24 mean ± SE change of -5.5 ± 0.3 kg (p<0.001) (a 6.5% weight loss from baseline). The change from baseline in FIQR and PSS scores were -29.1 ± 1.1 and -20.0 ± 0.8, respectively (both p<0.001), indicating a substantial improvement. Statistically significant improvements from baseline to Week 24 were observed in systolic and diastolic blood pressure, HbA1c, LDL and HDL cholesterol, and triglycerides (all p<0.001). The supplement was well tolerated; no adverse events were reported. Discussion: Sustained augmentation of IGF-1 with the test supplement may represent a novel method of improving clinical symptoms, including stress-related weight gain, in individuals with fibromyalgia and stress-associated low-normal hGH.
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Doenças Cardiovasculares , Fibromialgia , Hormônio do Crescimento Humano , Adulto , Humanos , Fibromialgia/tratamento farmacológico , Fator de Crescimento Insulin-Like I/metabolismo , Estudos Prospectivos , Estudos de Coortes , Aumento de Peso , Peso Corporal , Inquéritos e Questionários , AminoácidosRESUMO
Purpose: Effective, empathic communication is crucial for pediatric oncology clinicians when discussing palliative and end-of-life (PC/EOL) care with parents of children with cancer. Unfortunately, many parents report inadequate communication at these distressing times. This study evaluates the communication skills training (CST) clinicians received to deliver a PC/EOL communication intervention as part of a multi-site randomized-controlled trial (RCT). Methods: Clinicians from eight sites formed dyads (one physician and one nurse [RN] or advanced practice provider [APP]) and were trained over 3 days (in-person or virtually). Training was adapted from VitalTalk™ and included didactic instruction, videos, visual aids, and dedicated time to practice with simulated patients. Study participants completed a confidential, post-training online evaluation survey. A self-reported quality assurance checklist was used to measure fidelity to the communication protocol when delivered to parents during the RCT. Results: Thirty clinicians completed training; 26 completed post-training surveys including twelve (46.1%) physicians, 8 (30.8%) RNs and 6 (23.1%) APPs. Most were female (65.4%); white (80.8%), not Latinx (88.5%); 40-50 years old (53.9%); and in practice over 10 years (65.4%). Nine (34.6%) trained in-person; the rest trained virtually. Ninety-two percent reported the course was valuable or very valuable for developing their PC/EOL communication skills and 96% reported learning something new. Dyads trained virtually had similar fidelity to those trained in-person (95% and 90% respectively) when delivering the PC/EOL communication intervention to parents. Conclusion: This PC/EOL CST was valuable for improving pediatric oncology clinicians' communication skills, successfully implemented in-person and virtually, and translated effectively into practice.
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An oral test supplement increases serum human growth hormone (hGH) levels after acute administration in healthy adults. We investigated the mechanism for the increase in hGH and the effect of continued daily administration of the test supplement on measures of physical fitness and sleep efficiency. In Study 1, serum triiodothyronine (T3) was measured in samples from a prior placebo-controlled, double-blind study in which 16 healthy participants received both placebo and the test supplement in a crossover design; treatment order was randomized, and treatments were separated by a 1-week washout. In Study 2, physical fitness (VO2 max) was measured at baseline and after 2 weeks of daily administration of the test supplement (N = 12 healthy participants). Study 3 assessed daily sleep onset latency and time awake during 3 weeks of daily administration of the test supplement (N = 15 healthy participants). A fall from baseline in T3 was observed with placebo (-6.1 ± 8.5 ng/dL, P = .01). Of note, the change in T3 was smaller with the test supplement (-3.3 ± 10.7 ng/dL, P = not significant) but was not statistically different from placebo. Mean VO2 max increased by 6% from baseline after 2 weeks (P = .02). Sleep-onset latency and time awake during the night were reduced from baseline to week 3 by 22% and 65%, respectively (P = .01 and P = .02). The conservation of T3 levels suggests that the mechanism for increased hGH secretion by the test supplement is through somatostatin inhibition. Furthermore, pilot studies indicated that daily administration of the supplement improved physical fitness and sleep efficiency from baseline, effects consistent with increased endogenous hGH release. Clinical Trial Registration No. NCT02987868.
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Hormônio do Crescimento Humano , Adulto , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Aptidão Física , SonoRESUMO
AIMS: To gather opinions from UK medical students and recent graduates about their undergraduate training to prescribe and their confidence about meeting the relevant competencies identified by the General Medical Council (GMC). METHODS: We designed a web-based survey that was distributed to UK medical students and first year Foundation doctors (graduation years 2006-2008) via medical schools and postgraduate networks. RESULTS: Analysis was restricted to 2413 responses from students graduating in 2006-2008 from the 25 UK medical schools (mean 96.5 per school) with a complete undergraduate curriculum. Distinct courses and assessments in 'clinical pharmacology & therapeutics (or equivalent)' were identified by 17% and 13%, respectively, with mode of learning described most commonly as 'opportunistic learning during clinical attachments' (41%). Only 38% felt 'confident' about prescription writing and only a minority (35%) had filled in a hospital prescription chart more than three times during training. The majority (74%) felt that the amount of teaching in this area was 'too little' or 'far too little', and most tended to disagree or disagreed that their assessment 'thoroughly tested knowledge and skills' (56%). When asked if they were confident that they would be able to achieve the prescribing competencies set out by the GMC, 42% disagreed or tended to disagree, whereas only 29% agreed or tended to agree. CONCLUSIONS: Many respondents clearly perceived a lack of learning opportunities and assessment related to the safe and effective use of drugs and had little confidence that they would meet the competencies identified by the GMC. There is an urgent need to review undergraduate training in this area.
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Competência Clínica/normas , Currículo/normas , Prescrições de Medicamentos/normas , Educação de Graduação em Medicina/normas , Corpo Clínico Hospitalar/normas , Humanos , Estudantes de Medicina , Inquéritos e Questionários , Reino UnidoRESUMO
We present a full computational description of the fragmentation reactions of protonated diglycine (H(+)GG). Relaxed potential energy surface scans performed at B3LYP/6-31 G(d) or B3LYP/6-311 + G(d,p) levels are used to map the reaction coordinate surfaces and identify the transition states (TSs) and intermediate reaction species for seven reactions observed experimentally in the succeeding companion paper. All structures are optimized at the B3LYP/6-311 + G(d,p) level, with single point energies of the key optimized structures calculated at B3LYP and MP2(full) levels using a 6-311 + G(2 d,2p) basis set. These theoretical structures and energies are compared with extensive calculations in the literature. Although the pathways elucidated here are generally in agreement with those previously outlined, new details and, for some reactions, lower energy transition states are located. Further, the mechanism for the combined loss of carbon monoxide and ammonia is explored for the first time.
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Glicilglicina/química , Prótons , Íons/química , Modelos Moleculares , Espectrometria de Massas em Tandem , TermodinâmicaRESUMO
We present a full molecular description of fragmentation reactions of protonated diglycine (H(+)GG) by studying their collision-induced dissociation (CID) with Xe using a guided ion beam tandem mass spectrometer (GIBMS). Analysis of the kinetic energy-dependent CID cross sections provides the 0 K barriers for the sequential H(2)O+CO and CO+NH(3) losses from H(+)GG as well as for the reactions involved in y(1) and a(1) ion formation, after accounting for unimolecular decay rates, internal energy of reactant ions, and multiple ion-molecule collisions. Here, seven energetic barriers are measured for the fragmentation processes of H(+)GG, including the loss of H(2)O and of CO at ~140 and ~156 kJ/mol, the combined loss of (H(2)O+CO) and of (CO+NH(3)) at ~233 and ~185 kJ/mol, and formation of y(1) and a(1) ions at ~191 and ~212 kJ/mol, respectively, with a second channel for a(1) formation opening at ~326 kJ/mol. Theoretical energies from the preceding paper are compared with our experimental energies and found to be in good agreement. This validates the mechanisms explored computationally, including unambiguous identification of the b(2) ion as protonated 2-aminomethyl-5-oxazolone, thereby allowing a complete characterization of the elementary steps of H(+)GG decomposition. These results also demonstrate that all reactive species are available from the ground state conformation, as opposed to involving an initial broad distribution of protonated conformers. This result verifies the utility of the "mobile proton" model for understanding the fragmentation of protonated proteins.
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Glicilglicina/química , Prótons , Íons/química , Cinética , Modelos Moleculares , Espectrometria de Massas em Tandem , Termodinâmica , Xenônio/químicaRESUMO
The interactions of rubidium cations with the four amino acids (AA), glycine (Gly), serine (Ser), threonine (Thr), and proline (Pro), are examined in detail. Experimentally, the bond energies are determined using threshold collision-induced dissociation of the Rb(+)(AA) complexes with xenon in a guided ion beam tandem mass spectrometer. Analyses of the energy dependent cross sections include consideration of unimolecular decay rates, internal energy of reactant ions, and multiple ion-molecule collisions. 0 K bond energies of 108.9 +/- 7.0, 115.7 +/- 4.9, 122.1 +/- 4.6, and 125.2 +/- 4.5 kJ/mol are determined for complexes of Rb(+) with Gly, Ser, Thr, and Pro, respectively. Quantum chemical calculations are conducted at the B3LYP, B3P86, and MP2(full) levels of theory with geometries and zero point energies calculated at the B3LYP level using both HW*/6-311+G(2d,2p) and Def2TZVP basis sets. Results obtained using the former basis sets are systematically low compared to the experimental bond energies, whereas the latter basis sets show good agreement. For Rb(+)(Gly), the ground state conformer has the rubidium ion binding to the carbonyl group of the carboxylic acid, and a similar geometry is found for Rb(+)(Pro) except the secondary nitrogen accepts the carboxylic acid hydrogen to form the zwitterionic structure. Both Rb(+)(Ser) and Rb(+)(Thr) are found to have tridentate binding at the B3LYP and MP2(full) levels, whereas the B3P86 slightly prefers binding Rb(+) at the carboxylic acid. Comparison of these results to those for the lighter alkali ions provides insight into the trends in binding affinities and structures associated with metal cation variations.
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Aminoácidos/química , Cátions/química , Rubídio/química , Glicina/química , Prolina/química , Serina/química , Espectrometria de Massas em Tandem , Termodinâmica , Treonina/química , Xenônio/químicaRESUMO
Deamidation of the amino acid asparagine (Asn) is a primary route for spontaneous post-translational protein modification biologically and is a pH dependent process. Here we present a full molecular description of the deamidation and (H(2)O + CO) loss reactions of protonated asparagine, H(+)(Asn), by studying its collision-induced dissociation (CID) with Xe using a guided ion beam (GIB) tandem mass spectrometer. Analysis of the kinetic energy-dependent CID cross sections provides the 0 K barriers for the deamidation and (H(2)O + CO) loss reactions after accounting for unimolecular decay rates, internal energy of reactant ions, multiple ion-molecule collisions, and competition among the decay channels. Relaxed potential energy surface scans performed at the B3LYP/6-31G(d) level identify the transition-state (TS) and intermediate reaction species for these processes, structures that are further optimized at the B3LYP/6-311+G(d,p) level. Intrinsic reaction coordinate (IRC) calculations are also performed at this level on the rate-limiting reaction TSs to validate the molecular details and energy dependence of these species. Single point energies of the key optimized TSs and intermediates are calculated at B3LYP, B3P86, and MP2(full) levels using a 6-311+G(2d,2p) basis set. A number of alternative high-energy mechanisms for (H(2)O + CO) loss from H(+)(Asn) are also investigated. Combining both experimental work and quantum chemical calculations allows for a complete characterization of the elementary steps of these reactions as well as a comprehensive evaluation of the complex behavior of the deamidation reaction.