Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Acta Chir Belg ; 116(1): 36-40, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27385139

RESUMO

Background Chronic Kidney disease is a major health problem in the world. Native arteriovenous Fistula (AVF) is well established as the best vascular access for haemodialysis. Little is known about the outcome of AVF in sub-Saharan Africa. We aim to analyze the outcome of patients undergoing AVF creation during the pilot program established at the Douala general hospital (DGH). Method This was hospital-based, longitudinal study with a retrospective phase (April 2010-January 2014) and a prospective phase (January 2014-April 2014). All consecutive patients operated for AVF creation were included in this study. Socio-demographics data, functionality, and complications were analyzed. Results Eighty-one patients including 52 men were enrolled in this study (49 prospectively and 32 retrospectively). The mean age was 52, 3 years (range 18-81 years). Hypertension (66, 7%), diabetes (17, 3%), and HIV (8, 6%) were the most observed co-morbidities. About 96.3% of AVF were native and 3.7% were prosthetic graft. Radiocephalic AVF was performed at a rate of 77.8%. The primary function rate was 97.7% and the mean follow-up period 43.4 weeks. The overall rate of complications was 44.4% of whom 30.5% were early, 30.5% secondary, and 39% lasted. The treatment of these complications was conservative in 48.7% of cases. Conclusions The results of the pilot program of AVF creation at the DGH are encouraging. However, the sustainability of this project requires human capacity building.


Assuntos
Cateteres de Demora , Falência Renal Crônica/terapia , Diálise Peritoneal/métodos , Diálise Renal/métodos , Dispositivos de Acesso Vascular , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Camarões , Países em Desenvolvimento , Feminino , Seguimentos , Hospitais Gerais , Humanos , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/mortalidade , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades , Avaliação de Resultados em Cuidados de Saúde , Diálise Peritoneal/estatística & dados numéricos , Projetos Piloto , Diálise Renal/estatística & dados numéricos , Estudos Retrospectivos , Medição de Risco , Adulto Jovem
2.
Neurocrit Care ; 12(1): 35-42, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19806473

RESUMO

BACKGROUND: Altered brain perfusion may play an important role in the development of sepsis-associated encephalopathy. However, whether or not cerebral autoregulation (CA) is preserved in such condition has been debated. CA is dependent on cerebral vascular tone, the main determinant of which is the concentration of carbon dioxide (CO2). The purpose of this study was to evaluate the influence of PaCO2 on the cerebral autoregulatory capacity in patients with septic shock. METHODS: Using transcranial Doppler sonography recordings from the middle cerebral artery (MCA), we evaluated the static cerebral autoregulatory responses within the first 3 days of septic shock. Changes in cerebrovascular resistance (CVR) were calculated from the changes in the mean velocity in the MCA (VMCA, cm/s), in response to an increase in mean arterial pressure (MAP, mmHg) induced by vasopressors. The cerebral autoregulation index (CAI) was calculated as the ratio of the relative changes in CVR and MAP (CAI = DeltaMAP%/DeltaCVR%), with normal values ranging between 0 and 2. RESULTS: We studied 21 mechanically ventilated patients, with a baseline MAP of 65 +/- 6 mmHg, a mean VMCA of 60 +/- 20 cm/s and a median PaCO(2) of 35 [28-49] mmHg. Fourteen of the 21 patients had impaired CA, including 7 of the 14 patients with a PaCO2 <40 mmHg and all 7 patients with a PaCO2 >40 mmHg (Fisher's exact test, P = 0.046). CONCLUSIONS: According to these data, CA is impaired in the majority of patients with septic shock, especially in the presence of hypercapnia.


Assuntos
Encéfalo/irrigação sanguínea , Dióxido de Carbono/sangue , Homeostase/fisiologia , Hipóxia-Isquemia Encefálica/fisiopatologia , Choque Séptico/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo/fisiologia , Dominância Cerebral/fisiologia , Feminino , Escala de Coma de Glasgow , Humanos , Unidades de Terapia Intensiva , Masculino , Artéria Cerebral Média/fisiopatologia , Prognóstico , Estudos Prospectivos , Ultrassonografia Doppler Transcraniana , Resistência Vascular/fisiologia
3.
Cardiovasc Diagn Ther ; 9(1): 43-49, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30881876

RESUMO

BACKGROUND: Cardiac surgery is a growing activity in Sub-Saharan Africa, however, data related to long-term mortality are scarce. We aimed to analyze outcome data of cardiac interventions in two hospitals in Cameroon over 10 years' period. METHODS: we conducted a retrospective analytical and descriptive study at the Douala General Hospital and Yaoundé General Hospital. All patients operated between January 2007 and December 2017, or their families were contacted by phone between January and April 2018 for a free of charges medical examination. RESULTS: Of a total of 98 patients operated during the study period, 8 (8.2%) were lost to follow-up. Finally, 90 patients [49 (54.4%) women and 41 (45.6%)] men were included. The mean age was 49±22 years (range, 13-89 years). The surgical indications were valvular heart diseases in 37 (41.1%) cases, congenital heart diseases in 11 (12.2%) cases, chronic constrictive pericarditis in 4 (4.4%) cases, and intra cardiac tumor in 1 (1.1%) case. Valve replacement was the most common type of surgery carried out in 37 (41.1%) cases-mostly with mechanical prosthesis. Pacemaker-mostly dual-chambers were implanted in 36 (40.0%) patients. The median follow-up was 26 months. The overall late mortality was 5.7%, and the overall survival rates at 5 and 10 years were 95.5% and 94.4% respectively. The overall survival rates at 5 and 10 years for mechanical valve prosthesis were 93.3% and 90% respectively. The survival at 10 years was 100% for patients with bioprosthesis. The survival rates at 10 years were 94.1% and 100% respectively for dual and single chamber pacemaker. CONCLUSIONS: Long-term outcome of cardiac surgery in hospitals in Cameroon are acceptable with low mortality rate. However, outcome metrics beyond mortality should be implemented for a prospective data collection.

4.
Prog Brain Res ; 150: 495-511, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16186044

RESUMO

The locked-in syndrome (pseudocoma) describes patients who are awake and conscious but selectively deefferented, i.e., have no means of producing speech, limb or facial movements. Acute ventral pontine lesions are its most common cause. People with such brainstem lesions often remain comatose for some days or weeks, needing artificial respiration and then gradually wake up, but remaining paralyzed and voiceless, superficially resembling patients in a vegetative state or akinetic mutism. In acute locked-in syndrome (LIS), eye-coded communication and evaluation of cognitive and emotional functioning is very limited because vigilance is fluctuating and eye movements may be inconsistent, very small, and easily exhausted. It has been shown that more than half of the time it is the family and not the physician who first realized that the patient was aware. Distressingly, recent studies reported that the diagnosis of LIS on average takes over 2.5 months. In some cases it took 4-6 years before aware and sensitive patients, locked in an immobile body, were recognized as being conscious. Once a LIS patient becomes medically stable, and given appropriate medical care, life expectancy increases to several decades. Even if the chances of good motor recovery are very limited, existing eye-controlled, computer-based communication technology currently allow the patient to control his environment, use a word processor coupled to a speech synthesizer, and access the worldwide net. Healthy individuals and medical professionals sometimes assume that the quality of life of an LIS patient is so poor that it is not worth living. On the contrary, chronic LIS patients typically self-report meaningful quality of life and their demand for euthanasia is surprisingly infrequent. Biased clinicians might provide less aggressive medical treatment and influence the family in inappropriate ways. It is important to stress that only the medically stabilized, informed LIS patient is competent to consent to or refuse life-sustaining treatment. Patients suffering from LIS should not be denied the right to die - and to die with dignity - but also, and more importantly, they should not be denied the right to live - and to live with dignity and the best possible revalidation, and pain and symptom management. In our opinion, there is an urgent need for a renewed ethical and medicolegal framework for our care of locked-in patients.


Assuntos
Estado de Consciência , Quadriplegia/fisiopatologia , Quadriplegia/psicologia , Fala , Humanos , Quadriplegia/diagnóstico , Qualidade de Vida
5.
J Neurosurg ; 103(3 Suppl): 247-52, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16238078

RESUMO

OBJECT: The authors evaluate the incidence of persistent hydrocephalus after early surgical management of pediatric posterior fossa tumors and the indicators for routine preoperative endoscopic third ventriculostomy (ETV). METHODS: Between 1989 and 2004, 160 children with a posterior fossa tumor were treated at Erasme Hospital in Brussels, Belgium. Hydrocephalus was present at admission in 114 of the patients. Thirty-one patients had severe hydrocephalus (Evans index [EI] > 0.4). Twenty-four of these and the 83 patients with mild hydrocephalus (EI between 0.3 and 0.4) were treated with early posterior fossa surgery (Group 1; 107 patients). In this group, 93 patients underwent a total or subtotal tumor resection associated with external ventricular drainage (Group 1A), and 14 underwent a stereotactic biopsy associated with an ETV (Group 1B). The 53 remaining patients underwent elective posterior fossa surgery (Group 2). Early tumor resection (Group 1A) resolved hydrocephalus in 85 (91%) of 93 patients, whereas an ETV resolved intracranial hypertension in 11 patients (Group 1B). In Group 1, persistent hydrocephalus affected 11 (10%) of 107 patients, seven of whom had symptoms and were treated (three with shunts and four with ETVs). Persistent hydrocephalus was more frequent in children with severe preoperative hydrocephalus (p = 0.002) and with medulloblastomas (p = 0.0154). A total of 22 technically successful ETV procedures were performed. The ETV success rate for controlling hydrocephalus was 81% (18 of 22) and the rate of severe complications was 9% (two of 22). CONCLUSIONS: An ETV is an efficient procedure for controlling hydrocephalus associated with posterior fossa tumor. The authors confirm that a routine postoperative ETV is indicated for treating persistent hydrocephalus. For preventing it, however, they recommend early posterior fossa surgery whenever possible. The low rate of persistent hydrocephalus does not justify adopting routine preoperative ETVs.


Assuntos
Endoscopia/métodos , Hidrocefalia/etiologia , Neoplasias Infratentoriais/complicações , Neoplasias Infratentoriais/cirurgia , Ventriculostomia/métodos , Criança , Pré-Escolar , Feminino , Humanos , Hidrocefalia/epidemiologia , Incidência , Lactente , Recém-Nascido , Masculino , Recidiva , Estudos Retrospectivos , Terceiro Ventrículo/patologia , Terceiro Ventrículo/cirurgia
6.
Intensive Care Med ; 30(11): 2080-5, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15480565

RESUMO

OBJECTIVE: Post mortem examination rates have decreased worldwide and their usefulness has been challenged. The aim of this study was to compare ante- versus post mortem findings in a multidisciplinary ICU. DESIGN: Retrospective study. SETTING: Thirty-one-bed, medico-surgical ICU. PATIENTS: All patients who died on the ICU and underwent an autopsy examination in 1999. MEASUREMENTS: Records from autopsies were compared with clinical records. A modified Goldman's criteria was used to categorize the post mortem diagnoses. Unexpected findings were evaluated according to the duration of hospitalization prior to death (fewer than or more than 10 days). RESULTS: Among 2,984 ICU admissions, there were 489 deaths; 222 autopsies were conducted (45.4% autopsy rate). Post mortem examination revealed unexpected findings in 50 patients (22.5%), including malignancy (22 [9.9%]), fungal infections (9 [4%]), pulmonary embolism (7 [3.2%]), nosocomial infections (3 [1.3%]), Hashimoto's disease (3 [1.3%]), mesenteric infarction (2 [0.9%]), Barrett's esophagus (2 [0.9%]), endocarditis (1 [0.5%]) and myocardial infarction (1 [0.5%]). These unexpected findings were considered as major (Class I/II) in 19 (8.5%), and minor (Class III) in 31 (14%) patients. In patients with a short ICU length of stay (<10 days), there were more major unexpected findings than minor, while after a prolonged stay (>10 days), minor unexpected findings were more common. CONCLUSIONS: After a short ICU stay (<10 days), autopsy revealed discrepancies primarily related to the cause of death associated with diseases whose diagnosis can be difficult. Following more prolonged ICU stays (>10 days), autopsy was more likely to reveal coexisting diseases unrelated to death.


Assuntos
Autopsia , Causas de Morte , Erros de Diagnóstico , Unidades de Terapia Intensiva , Idoso , Bélgica/epidemiologia , Erros de Diagnóstico/estatística & dados numéricos , Feminino , Humanos , Tempo de Internação , Masculino , Estudos Retrospectivos
7.
J Crit Care ; 17(1): 58-62, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12040550

RESUMO

PURPOSE: To determine the neurologic outcome of patients with intracranial hypertension treated with barbiturate-induced coma. MATERIALS AND METHODS: The records of 49 patients who were admitted to a 31-bed medicosurgical intensive care unit over a 5-year period in whom a barbiturate coma was induced to control intracranial hypertension were analyzed retrospectively. Analysis included assessment of the response to barbiturate coma and evaluation of the long-term neurologic outcome according to the Glasgow Outcome Scale (GOS). RESULTS: Intracranial hypertension was caused by head trauma in 28 patients and subarachnoid hemorrhage in 21 patients. Eight of the head trauma patients and 5 of the patients with subarachnoid hemorrhage survived their hospital stay. The survivors were younger than the nonsurvivors, and had a good neurologic status after 1 year (except for 2 patients who died 1 and 3 months after discharge, respectively). There was no significant difference in the Glasgow Coma Score (GCS) on admission between the survivors and the nonsurvivors. The long-term outcome at 1 year was markedly better in the patients who had experienced a subarachnoid hemorrhage than in the trauma patients.


Assuntos
Barbitúricos/efeitos adversos , Barbitúricos/uso terapêutico , Coma/induzido quimicamente , Hipertensão Intracraniana/tratamento farmacológico , Resultado do Tratamento , Adolescente , Adulto , Bélgica , Criança , Feminino , Escala de Coma de Glasgow , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida
8.
Acta Neurol Belg ; 102(4): 177-85, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12534245

RESUMO

Positron emission tomography (PET) techniques represent a useful tool to better understand the residual brain function in vegetative state patients. It has been shown that overall cerebral metabolic rates for glucose are massively reduced in this condition. However, the recovery of consciousness from vegetative state is not always associated with substantial changes in global metabolism. This finding led us to hypothesize that some vegetative patients are unconscious not just because of a global loss of neuronal function, but rather due to an altered activity in some critical brain regions and to the abolished functional connections between them. We used voxel-based Statistical Parametric Mapping (SPM) approaches to characterize the functional neuroanatomy of the vegetative state. The most dysfunctional brain regions were bilateral frontal and parieto-temporal associative cortices. Despite the metabolic impairment, external stimulation still induced a significant neuronal activation (i.e., change in blood flow) in vegetative patients as shown by both auditory click stimuli and noxious somatosensory stimuli. However, this activation was limited to primary cortices and dissociated from higher-order associative cortices, thought to be necessary for conscious perception. Finally, we demonstrated that vegetative patients have impaired functional connections between distant cortical areas and between the thalami and the cortex and, more importantly, that recovery of consciousness is paralleled by a restoration of this cortico-thalamo-cortical interaction.


Assuntos
Córtex Cerebral/fisiopatologia , Circulação Cerebrovascular/fisiologia , Metabolismo Energético/fisiologia , Vias Neurais/fisiopatologia , Estado Vegetativo Persistente/fisiopatologia , Tálamo/fisiopatologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Estado de Consciência/fisiologia , Humanos , Vias Neurais/diagnóstico por imagem , Vias Neurais/patologia , Estado Vegetativo Persistente/diagnóstico por imagem , Estado Vegetativo Persistente/patologia , Recuperação de Função Fisiológica/fisiologia , Tálamo/diagnóstico por imagem , Tálamo/patologia , Tomografia Computadorizada de Emissão
10.
Heart Lung ; 38(5): 435-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19755194

RESUMO

BACKGROUND: Therapeutic aerosols are commonly used in mechanically ventilated patients. The position of the nebulizer in the ventilator circuit and the humidification of inhaled gases can influence the efficiency of aerosol delivery. We evaluated the effect of nebulizer position on the pulmonary bioavailability of nebulized ipratropium in ventilated patients without known preexisting respiratory disease. METHODS: The study included 38 mechanically ventilated and sedated patients after open heart surgery. Ipratropium (500 microg) was delivered by an ultrasonic nebulizer. Patients were randomized into 2 groups: the nebulizer positioned before the heat humidification system (group 1, n = 19) or at the end of the inspiratory limb before the Y-piece (group 2, n = 19). The amount of ipratropium in the urine collected during the 4 hours after drug administration was measured by mass spectrometry. RESULTS: There were no statistically significant differences in tidal volume or respiratory rate between groups. There were no significant differences between the 2 groups in the amount of drug excreted (group 1 vs 2: 13,237 +/- 2313 pg/mL vs 15,529 +/- 3204 pg/mL) or in pulmonary bioavailability (.9% +/- .1% vs 1.1% +/- .2%). CONCLUSION: The position of the nebulizer in the ventilatory circuit had no effect on the pulmonary bioavailability of ipratropium.


Assuntos
Aerossóis , Broncodilatadores/uso terapêutico , Procedimentos Cirúrgicos Cardíacos/métodos , Umidade , Ipratrópio/uso terapêutico , Pulmão/efeitos dos fármacos , Nebulizadores e Vaporizadores , Respiração Artificial/métodos , Administração por Inalação , Adulto , Idoso , Disponibilidade Biológica , Procedimentos Cirúrgicos Cardíacos/instrumentação , Feminino , Humanos , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade
11.
Crit Care Med ; 34(10): 2536-40, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16915107

RESUMO

OBJECTIVE: To test the hypothesis that administration of albumin to correct hypoalbuminemia might have beneficial effects on organ function in a mixed population of critically ill patients. DESIGN: : Prospective, controlled, randomized study. SETTING: Thirty-one-bed, mixed medicosurgical department of intensive care. PATIENTS: All adult patients with a serum albumin concentration < or =30 g/L were assessed for eligibility. Principal exclusion criteria were expected length of stay <72 hrs, life expectancy <3 months or a do-not-resuscitate order, albumin administration in the preceding 24 hrs, or evidence of fluid overload. INTERVENTIONS: The 100 patients were randomized to receive 300 mL of 20% albumin solution on the first day, then 200 mL/day provided their serum albumin concentration was <31 g/dL (albumin group), or to receive no albumin (control group). MEASUREMENTS AND MAIN RESULTS: The primary outcome was the effect of albumin administration on organ function as assessed by a delta Sequential Organ Failure Assessment score from day 1 to day 7 (or the day of intensive care discharge or death, whichever came first). The two groups of 50 patients were comparable at baseline for age, gender, albumin concentration, and Acute Physiology and Chronic Health Evaluation II score. Albumin concentration did not change over time in the control group but increased consistently in the albumin group (p < .001). Organ function improved more in the albumin than in the control group (p = .026), mainly due to a difference in respiratory, cardiovascular, and central nervous system components of the Sequential Organ Failure Assessment score. Diuretic use was identical in both groups, but mean fluid gain was almost three times higher in the control group (1679 +/- 1156 vs. 658 +/- 1101 mL, p = .04). Median daily calorie intake was higher in the albumin than in the control group (1122 [935-1158] vs. 760 [571-1077] kcal, p = .05). CONCLUSIONS: Albumin administration may improve organ function in hypoalbuminemic critically ill patients. It results in a less positive fluid balance and a better tolerance to enteral feeding.


Assuntos
Albuminas/uso terapêutico , Hipoalbuminemia/terapia , Insuficiência de Múltiplos Órgãos/prevenção & controle , Adulto , Feminino , Hidratação/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Estatísticas não Paramétricas
12.
Crit Care Med ; 33(6): 1392-9, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15942361

RESUMO

OBJECTIVE: To review the current understanding of the medical management of severe brain injury. DATA SOURCE: The MEDLINE database, bibliographies of selected articles, and current English-language texts on the subject. STUDY SELECTION: Studies related to management of intracranial hypertension, traumatic brain injury, and brain edema. DATA EXTRACTION: All studies relevant to the subject under consideration were considered, with a focus on clinical studies in adults. DATA SYNTHESIS: Basic rules of resuscitation must apply, including adequate ventilation, appropriate fluid administration, and cardiovascular support. The control of intracranial pressure can be considered in three steps. The first step should be initial slight hyperventilation with a target PaCO2 of 35 mm Hg and cerebrospinal fluid drainage for intracranial pressure of >15-20 mm Hg. The second step should be mannitol or hypertonic saline and hyperventilation to target PaCO2 of 28-35 mm Hg. The third step should be barbiturate coma or decompressive craniectomy. Additional management issues, including seizure prophylaxis, sedation, nutritional support, use of hypothermia, and corticosteroids, are also discussed. CONCLUSIONS: Brain injury is frequently associated with the development of brain edema and the development of intracranial hypertension. However, with a coordinated, stepwise, and aggressive approach to management, focusing on control of intracranial pressure without adversely affecting cerebral perfusion pressure, outcomes can be good.


Assuntos
Lesões Encefálicas/terapia , Algoritmos , Edema Encefálico/diagnóstico , Edema Encefálico/terapia , Lesões Encefálicas/diagnóstico , Lesões Encefálicas/fisiopatologia , Humanos , Hipertensão Intracraniana/diagnóstico , Hipertensão Intracraniana/terapia , Prognóstico
13.
Am J Physiol Endocrinol Metab ; 285(5): E1089-94, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12824083

RESUMO

Muscle hypertrophy during resistance training is reportedly increased by creatine supplementation. Having previously failed to find an anabolic effect on muscle protein turnover at rest, either fed or fasted, we have now examined the possibility of a stimulatory effect of creatine in conjunction with acute resistance exercise. Seven healthy men (body mass index, 23 +/- 2 kg/m2, 21 +/- 1 yr, means +/- SE) performed 20 x 10 repetitions of leg extension-flexion at 75% one-repetition maximum in one leg, on two occasions, 4 wk apart, before and after ingesting 21 g/day creatine for 5 days. The subjects ate approximately 21 g maltodextrin + 6 g protein/h for 3 h postexercise. We measured incorporation of [1-13C]leucine into quadriceps muscle proteins in the rested and exercised legs. Leg protein breakdown (as dilution of [2H5]phenylalanine) was also assessed in the exercised and rested leg postexercise. Creatine supplementation increased muscle total creatine by approximately 21% (P < 0.01). Exercise increased the synthetic rates of myofibrillar and sarcoplasmic proteins by two- to threefold (P < 0.05), and leg phenylalanine balance became more positive, but creatine was without any anabolic effect.


Assuntos
Creatina/administração & dosagem , Exercício Físico , Proteínas Musculares/biossíntese , Miofibrilas/metabolismo , Retículo Sarcoplasmático/metabolismo , Adulto , Biópsia , Velocidade do Fluxo Sanguíneo , Isótopos de Carbono , Creatina/análise , Deutério , Dieta , Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais , Humanos , Cinética , Perna (Membro)/irrigação sanguínea , Leucina/metabolismo , Masculino , Músculo Esquelético/química , Miofibrilas/efeitos dos fármacos , Fenilalanina/metabolismo , Polissacarídeos/administração & dosagem , Retículo Sarcoplasmático/efeitos dos fármacos
14.
Am J Physiol Endocrinol Metab ; 284(4): E764-70, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12475751

RESUMO

Dietary creatine supplementation is associated with increases in muscle mass, but the mechanism is unknown. We tested the hypothesis that creatine supplementation enhanced myofibrillar protein synthesis (MPS) and diminished muscle protein breakdown (MPB) in the fed state. Six healthy men (26 +/- 7 yr, body mass index 22 +/- 4 kg/m(2)) were studied twice, 2-4 wk apart, before and after ingestion of creatine (21 g/day, 5 days). We carried out two sets of measurements within 5.5 h of both MPS (by incorporation of [1-(13)C]leucine in quadriceps muscle) and MPB (as dilution of [1-(13)C]leucine or [(2)H(5)]phenylalanine across the forearm); for the first 3 h, the subjects were postabsorptive but thereafter were fed orally (0.3 g maltodextrin and 0.083 g protein. kg body wt(-1) x h(-1)). Creatine supplementation increased muscle total creatine by approximately 30% (P < 0.01). Feeding had significant effects, doubling MPS (P < 0.001) and depressing MPB by approximately 40% (P < 0.026), but creatine had no effect on turnover in the postabsorptive or fed states. Thus any increase in muscle mass accompanying creatine supplementation must be associated with increased physical activity.


Assuntos
Creatina/administração & dosagem , Proteínas Musculares/biossíntese , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Trifosfato de Adenosina/metabolismo , Adulto , Aminoácidos/farmacocinética , Peso Corporal , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Antebraço/irrigação sanguínea , Humanos , Masculino , Período Pós-Prandial/fisiologia , Fluxo Sanguíneo Regional/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA