Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
Rev. bras. ciênc. avic ; 24(3): eRBCA-2021-1524, 2022. tab, graf
Artículo en Inglés | VETINDEX | ID: biblio-1382162

RESUMEN

This study aimed to investigate the effect of tetramethylpyrazine (TMP) supplementation on egg production, nutrient retention and cecal microbiota diversity using 288 commercial Hy-Line brown hens as of wk 75 to 86. Four treatments consisted of TMP addition at 0 (control, basal diet), 100, 150 and 200 mg/kg of diet. The results showed that diets supplemented with TMP addition improved egg-laying rate as of wk 77 compared to the control, which led to an increase (p<0.001) of egg mass by 97-225 g/hen throughout the whole trial, and a linear increase (p=0.003) of egg mass to the incremental TMP doses was found. At wk 86, the apparent digestibilities of dry matter and crude protein were enhanced (p<0.05), exhibiting consistent linear increases (p≤0.033) with the TMP doses. However, TMP did not cause alpha and beta diversity of cecal microbiota. The results suggest that TMP can be an additive to improve egg production and nutrient digestibility of aged laying hens.(AU)


Asunto(s)
Animales , Pirazinas/efectos adversos , Pollos/fisiología , Suplementos Dietéticos/análisis , Microbioma Gastrointestinal/fisiología , Biodiversidad , Huevos/análisis
2.
Sci Rep ; 11(1): 19998, 2021 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-34620963

RESUMEN

Understanding the effects of metabolism on the rational design of novel and more effective drugs is still a considerable challenge. To the best of our knowledge, there are no entirely computational strategies that make it possible to predict these effects. From this perspective, the development of such methodologies could contribute to significantly reduce the side effects of medicines, leading to the emergence of more effective and safer drugs. Thereby, in this study, our strategy is based on simulating the electron ionization mass spectrometry (EI-MS) fragmentation of the drug molecules and combined with molecular docking and ADMET models in two different situations. In the first model, the drug is docked without considering the possible metabolic effects. In the second model, each of the intermediates from the EI-MS results is docked, and metabolism occurs before the drug accesses the biological target. As a proof of concept, in this work, we investigate the main antiviral drugs used in clinical research to treat COVID-19. As a result, our strategy made it possible to assess the biological activity and toxicity of all potential by-products. We believed that our findings provide new chemical insights that can benefit the rational development of novel drugs in the future.


Asunto(s)
Antivirales/metabolismo , Tratamiento Farmacológico de COVID-19 , Descubrimiento de Drogas , SARS-CoV-2/efectos de los fármacos , Adenina/efectos adversos , Adenina/análogos & derivados , Adenina/metabolismo , Adenina/farmacología , Adenosina/efectos adversos , Adenosina/análogos & derivados , Adenosina/metabolismo , Adenosina/farmacología , Adenosina Monofosfato/efectos adversos , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/metabolismo , Adenosina Monofosfato/farmacología , Alanina/efectos adversos , Alanina/análogos & derivados , Alanina/metabolismo , Alanina/farmacología , Amidas/efectos adversos , Amidas/metabolismo , Amidas/farmacología , Antivirales/efectos adversos , Antivirales/farmacología , COVID-19/metabolismo , Cloroquina/efectos adversos , Cloroquina/análogos & derivados , Cloroquina/metabolismo , Cloroquina/farmacología , Diseño de Fármacos , Humanos , Redes y Vías Metabólicas , Simulación del Acoplamiento Molecular , Nitrocompuestos/efectos adversos , Nitrocompuestos/metabolismo , Nitrocompuestos/farmacología , Pirazinas/efectos adversos , Pirazinas/metabolismo , Pirazinas/farmacología , Pirrolidinas/efectos adversos , Pirrolidinas/metabolismo , Pirrolidinas/farmacología , Ribavirina/efectos adversos , Ribavirina/metabolismo , Ribavirina/farmacología , SARS-CoV-2/metabolismo , Tiazoles/efectos adversos , Tiazoles/metabolismo , Tiazoles/farmacología
3.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;48(7): 622-628, 07/2015. graf
Artículo en Inglés | LILACS | ID: lil-751346

RESUMEN

Posthemorrhagic shock mesenteric lymph (PHSML) is a key factor in multiple organ injury following hemorrhagic shock. We investigated the role of hydrogen sulfide (H2S) in PHSML drainage in alleviating acute kidney injury (AKI) by administering D,L-propargylglycine (PPG) and sodium hydrosulfide hydrate (NaHS) to 12 specific pathogen-free male Wistar rats with PHSML drainage. A hemorrhagic shock model was established in 4 experimental groups: shock, shock+drainage, shock+drainage+PPG (45 mg/kg, 0.5 h prehemorrhage), and shock+drainage+NaHS (28 µmol/kg, 0.5 h prehemorrhage). Fluid resuscitation was performed after 1 h of hypotension, and PHMSL was drained in the last three groups for 3 h after resuscitation. Renal function and histomorphology were assessed along with levels of H2S, cystathionine-γ-lyase (CSE), Toll-like receptor 4 (TLR4), interleukin (IL)-10, IL-12, and tumor necrosis factor (TNF)-α in renal tissue. Hemorrhagic shock induced AKI with increased urea and creatinine levels in plasma and higher H2S, CSE, TLR4, IL-10, IL-12, and TNF-α levels in renal tissue. PHSML drainage significantly reduced urea, creatinine, H2S, CSE, and TNF-α but not TLR4, IL-10, or IL-12. PPG decreased creatinine, H2S, IL-10, and TNF-α levels, but this effect was reversed by NaHS administration. In conclusion, PHSML drainage alleviated AKI following hemorrhagic shock by preventing increases in H2S and H2S-mediated inflammation.


Asunto(s)
Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Ácidos Borónicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Ácidos Hidroxámicos/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Pirazinas/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Ácidos Borónicos/efectos adversos , Supervivencia sin Enfermedad , Ácidos Hidroxámicos/efectos adversos , Pirazinas/efectos adversos , Resultado del Tratamiento
4.
J Clin Rheumatol ; 21(1): 31-2, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25539431

RESUMEN

Primary Sjögren syndrome (PSS) is a chronic autoimmune disease characterized by sicca complex and various systemic manifestations. Although it is well accepted to use corticosteroids for the treatment of systemic manifestations, there is scarce information available regarding the use of targeted therapy for refractory cases. We describe a case of a severe PSS patient refractory to conventional treatment with a response to bortezomib, a proteasome inhibitor commonly used for the treatment of multiple myeloma. Bortezomib administration resulted in a notable improvement of the general symptoms, particularly fatigue, and a decrease in serum globulin levels as well as in serum viscosity. Hyperglobulinemic purpura disappeared, and prednisone tapering succeeded. Because of chronicity, no clinical changes were observed in sicca symptoms. As far as we know, this is the first report on the use of bortezomib in a refractory case of PSS.


Asunto(s)
Ácidos Borónicos/uso terapéutico , Resistencia a Medicamentos , Inhibidores de Proteasoma/uso terapéutico , Pirazinas/uso terapéutico , Índice de Severidad de la Enfermedad , Síndrome de Sjögren/tratamiento farmacológico , Corticoesteroides/uso terapéutico , Adulto , Ácidos Borónicos/efectos adversos , Bortezomib , Fatiga/tratamiento farmacológico , Fatiga/epidemiología , Fatiga/etiología , Femenino , Globulinas/metabolismo , Humanos , Incidencia , Inhibidores de Proteasoma/efectos adversos , Pirazinas/efectos adversos , Síndrome de Sjögren/complicaciones , Síndrome de Sjögren/metabolismo , Resultado del Tratamiento
5.
Int J Clin Pract ; 65(9): 930-8, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21849007

RESUMEN

AIM: The efficacy and safety of sitagliptin (SITA) monotherapy and SITA/metformin (MET) vs. pioglitazone (PIO) were assessed in patients with type 2 diabetes and moderate-to-severe hyperglycaemia (A1C = 7.5-12.0%). METHODS: In an initial 12-week phase (Phase A), 492 patients were randomised 1 : 1 in a double-blind fashion to SITA (100 mg qd) or PIO (15 mg qd, up-titrated to 30 mg after 6 weeks). In Phase B (28 additional weeks), the SITA group was switched to SITA/MET (up-titrated to 50/1000 mg bid over 4 weeks) and the PIO group was up-titrated to 45 mg qd RESULTS: At the end of Phase A, mean changes from baseline were -1.0% and -0.9% for A1C; -26.6 mg/dl and -28.0 mg/dl for fasting plasma glucose; and -52.8 mg/dl and -50.1 mg/dl for 2-h post-meal glucose for SITA and PIO, respectively. At the end of Phase B, improvements in glycaemic parameters were greater with SITA/MET vs. PIO: -1.7% vs. -1.4% for A1C (p = 0.002); -45.8 mg/dl vs. -37.6 mg/dl for fasting plasma glucose (p = 0.03); -90.3 mg/dl vs. -69.1 mg/dl for 2-h postmeal glucose (p = 0.001); and 55.0% vs. 40.5% for patients with A1C < 7% (p = 0.004). A numerically higher incidence of gastrointestinal adverse events and a significantly lower incidence of oedema were observed with SITA/MET vs. PIO. The incidence of hypoglycaemia was similarly low in both groups. Body weight decreased with SITA/MET and increased with PIO (-1.1 kg vs. 3.4 kg; p < 0.001). CONCLUSION: Improvements in glycaemic control were greater with SITA/MET vs. PIO, with weight loss vs. weight gain. Both treatments were generally well tolerated.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Metformina/administración & dosificación , Pirazinas/administración & dosificación , Tiazolidinedionas/administración & dosificación , Triazoles/administración & dosificación , Adolescente , Adulto , Anciano , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Método Doble Ciego , Quimioterapia Combinada/métodos , Ayuno/sangre , Femenino , Humanos , Hipoglucemiantes/efectos adversos , Masculino , Metformina/efectos adversos , Persona de Mediana Edad , Pioglitazona , Pirazinas/efectos adversos , Fosfato de Sitagliptina , Tiazolidinedionas/efectos adversos , Resultado del Tratamiento , Triazoles/efectos adversos , Adulto Joven
6.
Lancet Oncol ; 12(5): 431-40, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21507715

RESUMEN

BACKGROUND: Intravenous injection is the standard administration route of bortezomib; however, subcutaneous administration is an important alternative. We compared the efficacy and safety of subcutaneous versus intravenous bortezomib at the approved 1·3 mg/m(2) dose and twice per week schedule in patients with relapsed multiple myeloma. METHODS: This randomised, phase 3 study was undertaken at 53 centres in ten countries in Europe, Asia, and South America. Patients aged 18 years and older with relapsed multiple myeloma after one to three previous lines of therapy were randomly assigned to receive up to eight 21-day cycles of bortezomib 1·3 mg/m(2), on days 1, 4, 8, and 11, by subcutaneous injection or intravenous infusion. Randomisation was by an interactive voice response system based on a computer-generated randomisation schedule, stratified by number of previous lines and disease stage. Patients and treating physicians were not masked to treatment allocation. The primary objective was to show non-inferiority of subcutaneous versus intravenous bortezomib in terms of overall response rate (ORR) after four cycles in all patients with a diagnosis of measurable, secretory multiple myeloma who received one or more dose of drug (response-evaluable population). Non-inferiority was defined as retaining 60% of the intravenous treatment effect. This study is registered with ClinicalTrials.gov, number NCT00722566, and is ongoing for long-term follow-up. FINDINGS: 222 patients were randomly assigned to receive subcutaneous (n=148) or intravenous (n=74) bortezomib. The response-evaluable population consisted of 145 patients in the subcutaneous group and 73 in the intravenous group. Patients received a median of eight cycles (range one to ten) in both groups. ORR after four cycles was 42% in both groups (61 patients in subcutaneous group and 31 in intravenous group; ORR difference -0·4%, 95% CI -14·3 to 13·5), showing non-inferiority (p=0·002). After a median follow-up of 11·8 months (IQR 7·9-16·8) in the subcutaneous group and 12·0 months (8·1-15·6) in the intravenous group, there were no significant differences in time to progression (median 10·4 months, 95% CI 8·5-11·7, vs 9·4 months, 7·6-10·6; p=0·387) and 1-year overall survival (72·6%, 95% CI 63·1-80·0, vs 76·7%, 64·1-85·4; p=0·504) with subcutaneous versus intravenous bortezomib. Grade 3 or worse adverse events were reported in 84 (57%) patients in the subcutaneous group versus 52 (70%) in the intravenous group; the most common were thrombocytopenia (19 [13%] vs 14 [19%]), neutropenia (26 [18%] vs 13 [18%]), and anaemia (18 [12%] vs six [8%]). Peripheral neuropathy of any grade (56 [38%] vs 39 [53%]; p=0·044), grade 2 or worse (35 [24%] vs 30 [41%]; p=0·012), and grade 3 or worse (nine [6%] vs 12 [16%]; p=0·026) was significantly less common with subcutaneous than with intravenous administration. Subcutaneous administration was locally well tolerated. INTERPRETATION: Subcutaneous bortezomib offers non-inferior efficacy to standard intravenous administration, with an improved safety profile. FUNDING: Johnson & Johnson Pharmaceutical Research and Development, and Millennium Pharmaceuticals.


Asunto(s)
Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Ácidos Borónicos/administración & dosificación , Ácidos Borónicos/efectos adversos , Mieloma Múltiple/tratamiento farmacológico , Pirazinas/administración & dosificación , Pirazinas/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Asia , Células Sanguíneas/efectos de los fármacos , Bortezomib , Supervivencia sin Enfermedad , Esquema de Medicación , Europa (Continente) , Humanos , Infusiones Intravenosas , Inyecciones Subcutáneas , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Mieloma Múltiple/sangre , Mieloma Múltiple/etnología , Mieloma Múltiple/patología , Estadificación de Neoplasias , Enfermedades del Sistema Nervioso Periférico/inducido químicamente , Inhibidores de Proteasas/administración & dosificación , Inhibidores de Proteasas/efectos adversos , Recurrencia , América del Sur , Resultado del Tratamiento
7.
Diabetes Obes Metab ; 12(3): 252-61, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20070351

RESUMEN

AIM: To compare the efficacy and safety of monotherapy with sitagliptin and metformin in treatment-naïve patients with type 2 diabetes. METHODS: In a double-blind study, 1050 treatment-naïve patients (i.e. not taking an antihyperglycaemic agent for > or =16 weeks prior to study entry) with type 2 diabetes and an HbA(1c) 6.5-9% were randomized (1:1) to treatment with once-daily sitagliptin 100 mg (N = 528) or twice-daily metformin 1000 mg (N = 522) for 24 weeks. Metformin was up-titrated from 500 to 2000 mg per day (or maximum tolerated daily dose > or =1000 mg) over a period of 5 weeks. The primary analysis used a per-protocol (PP) approach to assess whether sitagliptin was non-inferior to metformin based on HbA(1c) change from baseline at week 24. Non-inferiority was to be declared if the upper boundary of the 95% confidence interval (CI) for the between-group difference in this endpoint was <0.40%. RESULTS: From a mean baseline HbA(1c) of 7.2% in the PP population, HbA(1c) change from baseline was -0.43% with sitagliptin (n = 455) and -0.57% with metformin (n = 439). The between-group difference (95% CI) was 0.14% (0.06, 0.21), thus confirming non-inferiority. Baseline HbA(1c) influenced treatment response, with larger reductions in HbA(1c) observed in patients with baseline HbA(1c)> or =8% in the sitagliptin (-1.13%; n = 74) and metformin (-1.24%; n = 73) groups. The proportions of patients at week 24 with HbA(1c) values at the goals of <7 or <6.5% were 69 and 34% with sitagliptin and 76 and 39% with metformin, respectively. Fasting plasma glucose changes from baseline were -11.5 mg/dL (-0.6 mmol/l) and -19.4 mg/dl (-1.1 mmol/l) with sitagliptin and metformin, respectively (difference in LS mean change from baseline [95% CI] = 8.0 mg /dl [4.5,11.4]). Both treatments led to similar improvements from baseline in measures of homeostasis model assessment-beta cell function (HOMA-beta) and insulin resistance (HOMA-IR). The incidence of hypoglycaemia was 1.7% with sitagliptin and 3.3% with metformin (p = 0.116). The incidence of gastrointestinal-related adverse experiences was substantially lower with sitagliptin (11.6%) compared with metformin (20.7%) (difference in incidence [95% CI] = -9.1% [-13.6,-4.7]), primarily because of significantly decreased incidences of diarrhoea (3.6 vs. 10.9%; p < 0.001) and nausea (1.1 vs. 3.1%; p = 0.032). Body weight was reduced from baseline with both sitagliptin (LS mean change [95% CI] = -0.6 kg [-0.9,-0.4]) and metformin (-1.9 kg [-2.2, -1.7]) (p < 0.001 for sitagliptin vs. metformin). CONCLUSIONS: In this 24-week monotherapy study, sitagliptin was non-inferior to metformin in improving HbA(1c) in treatment-naïve patients with type 2 diabetes. Although both treatments were generally well tolerated, a lower incidence of gastrointestinal-related adverse experiences was observed with sitagliptin.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Metformina/administración & dosificación , Pirazinas/administración & dosificación , Triazoles/administración & dosificación , Adolescente , Adulto , Anciano , Diabetes Mellitus Tipo 2/sangre , Método Doble Ciego , Femenino , Hemoglobina Glucada/metabolismo , Humanos , Hipoglucemiantes/efectos adversos , Masculino , Metformina/efectos adversos , Persona de Mediana Edad , Pirazinas/efectos adversos , Fosfato de Sitagliptina , Resultado del Tratamiento , Triazoles/efectos adversos , Adulto Joven
8.
Expert Opin Pharmacother ; 9(9): 1495-507, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18518780

RESUMEN

BACKGROUND: Sitagliptin is a highly selective oral dipeptidyl peptidase-4 inhibitor. This drug increases the plasma concentration of active glucagon like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide. These two hormones then simulate the secretion of insulin in a glucose-dependent manner and inhibit glucagon secretion, thus reducing circulating glucose levels. In animal models, GLP-1 increases beta-cell mass. OBJECTIVE: To review the efficacy and safety of sitagliptin in combined therapies (as add on or initial combination treatment) in type 2 diabetes. METHODS: A Medline search on published clinical trials involving sitagliptin in combined therapies was performed; additional information from published papers and abstracts to congresses on preclinical and basic science issues was also included to support the mechanistic rationale of combinations. RESULTS/CONCLUSION: In humans sitagliptin administration reduces fasting and postprandial glucose and A1c levels. Sitagliptin is as effective as glipizide (close to 0.7% mean A1c reduction), but has fewer hypoglycemic events than other oral insulin secretagogues. Since metformin reduces hepatic glucose production and increases GLP-1 release, combined therapy with sitagliptin becomes complementary and has been shown to have important additive effects. Sitagliptin combined with pioglitazone resulted in improved metabolic control when compared with pioglitazone plus placebo. Combined administration with insulin requires further studies. The weight neutral effect of sitagliptin, its glucose-dependent action (lower risk of hypoglycemia), the beneficial effects on beta-cell function and its eventual protective action on beta-cell mass makes it an excellent option for monotherapy or combined with metformin, glitazones or even sulfonylurea.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Incretinas , Pirazinas/uso terapéutico , Triazoles/uso terapéutico , Ensayos Clínicos como Asunto , Diabetes Mellitus Tipo 2/metabolismo , Dipeptidil Peptidasa 4/metabolismo , Inhibidores de la Dipeptidil-Peptidasa IV , Quimioterapia Combinada , Polipéptido Inhibidor Gástrico/metabolismo , Péptido 1 Similar al Glucagón/agonistas , Péptido 1 Similar al Glucagón/metabolismo , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/efectos adversos , Incretinas/agonistas , Incretinas/antagonistas & inhibidores , Incretinas/metabolismo , Fragmentos de Péptidos/metabolismo , Pirazinas/administración & dosificación , Pirazinas/efectos adversos , Fosfato de Sitagliptina , Resultado del Tratamiento , Triazoles/administración & dosificación , Triazoles/efectos adversos
9.
Curr Opin Oncol ; 18(4): 307-15, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16721122

RESUMEN

PURPOSE OF REVIEW: Major advances have been achieved in the field of biologically based therapies for cancer in the last few years, and some of the recently approved 'molecular-targeted therapies' are now being used in daily clinical practice. We aim to review some aspects of the toxicity and safety of small-molecule anti-cancer molecular-targeted therapies, with some insights into the physiopathology and predictive factors of toxicity, its correlation with response, and how to prevent and overcome it. RECENT FINDINGS: As a whole, small-molecule molecular-targeted therapies are well tolerated. Their toxic profile is favorable, but during the drug development process some severe (sometimes lethal) toxicities have been observed, such as interstitial lung disease in patients treated with drugs targeting the epidermal growth factor receptor. Pharmacogenomic studies can help us to identify those patients with well characterized polymorphisms, and to define the best-tolerated and most effective treatments. SUMMARY: Molecular-targeted therapies have a good toxicity profile in general; however, some patients are exquisitely sensitive to developing particular and severe toxicities related to these drugs.


Asunto(s)
Antineoplásicos/efectos adversos , Factores Inmunológicos/efectos adversos , Neoplasias/terapia , Ácidos Borónicos/efectos adversos , Bortezomib , Diseño de Fármacos , Farnesiltransferasa/antagonistas & inhibidores , Humanos , Lenalidomida , Inhibidores de Proteasas/farmacología , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Pirazinas/efectos adversos , Receptores de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Talidomida/efectos adversos , Talidomida/análogos & derivados
10.
J Pediatr Endocrinol Metab ; 13(8): 1115-20, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11085190

RESUMEN

Recent studies in adult volunteers have demonstrated that the free fatty acid reduction induced by acipimox, a nicotinic acid analog, stimulated GH secretion per se and enhanced in an additive manner the GH secretion elicited by such different stimuli as pyridostigmine, GHRH and GHRP-6. In order to evaluate whether acipimox administration stimulates GH secretion in prepubertal children, we administered a single oral dose of acipimox (100 mg for children weighing <30 kg and 200 mg for those >30 kg) to 14 healthy prepubertal children with a mean age of 8.2 +/- 1.9 years, a mean bone age of 6.2 +/- 3.0 years, growing along the 5-10th percentiles, and with normal thyroid function and IGF-I levels. Acipimox administration elicited a sustained increase in GH from a mean baseline level of 0.6 +/- 0.4 to 6.7 +/- 2.4 microg/l at the end of the test (p<0.05), with a mean GH peak of 10.5 +/- 3.5 microg/l. GH release was delayed so that peak GH levels were achieved 180 minutes after acipimox administration. In order to determine whether acipimox was capable of enhancing the GH secretion elicited by levodopa (L-Dopa), we administered either oral L-Dopa (250 mg for children weighing <30 kg and 500 mg for those >30 kg) or oral acipimox plus L-Dopa to the same children on different days. GH concentrations increased in a similar fashion following either of these tests (from a baseline level of 1.2 +/- 0.4 and 0.7 +/- 0.4 microg/l to 8.4 +/- 2.7 and 9.3 +/- 2.9 microg/l at the end of the test (p<0.001), with peak GH concentrations of 13.1 +/- 4.1 and 11.8 +/- 3.3 microg/l after L-Dopa or acipimox plus L-Dopa, respectively). Although the peak GH concentrations obtained after the combined administration of acipimox plus L-Dopa were similar to those obtained after either acipimox or L-Dopa administration, a larger number of our patients reached a GH cut-off point of >7 microg/l following combined therapy than with either stimulus alone (13/14 patients with combined therapy and 10/14 with acipimox alone). No side effects other than mild facial flushing were noted after acipimox administration. These results indicate that: 1) following the administration of a single oral dose of acipimox, significant GH secretion was elicited in healthy short prepubertal children; 2) the combined administration of acipimox plus L-Dopa did not, however, enhance the GH secretion of this group of children; 3) acipimox was well tolerated with minimal side effects; and 4) further studies in both GH sufficient and GH deficient children are necessary to evaluate acipimox's usefulness in assessing GH reserve.


Asunto(s)
Estatura , Hormona de Crecimiento Humana/metabolismo , Niacina/análogos & derivados , Pirazinas/uso terapéutico , Niño , Preescolar , Quimioterapia Combinada , Femenino , Hormona de Crecimiento Humana/sangre , Humanos , Levodopa/uso terapéutico , Masculino , Pubertad , Pirazinas/efectos adversos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA