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1.
Infez Med ; 19(2): 91-9, 2011 Jun.
Artigo em Italiano | MEDLINE | ID: mdl-21753248

RESUMO

Antibiotic therapy is a crucial and often life-saving strategy. This study assessed the ability to prescribe antibiotic therapy among a series of Italian postgraduate students in geriatrics and internal medicine. Participants were administered an anonymous questionnaire consisting of self-assessment of their ability to prescribe antibiotics and then manage a case of community-acquired pneumonia. The Wilcoxon test for comparisons between two independent samples was used for statistical analysis. Almost half the 70 students considered their knowledge of antibiotic therapy insufficient and were not satisfied with the notions received during their studies. Indeed, the change in antibiotic therapy required to control acute exacerbation of pneumonia was correctly identified by only 36% of students. Moreover, 38% of them gave the correct answer on factors influencing the duration of antibiotic therapy in the presence of definite improvement of pneumonia. No significant difference was found between the responses of residents in geriatrics and internal medicine. Overall, our study shows that nearly half of our students think they have inadequate antibiotic prescribing skills. This is confirmed by a low ability to establish the best management of the clinical case. To repair this severe shortcoming, different training methods need to be compared and more effective forms of instruction adopted.


Assuntos
Antibacterianos , Competência Clínica , Prescrições de Medicamentos/normas , Geriatria , Medicina Interna , Internato e Residência , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Humanos , Itália , Masculino , Inquéritos e Questionários
2.
Arch Gerontol Geriatr ; 49 Suppl 1: 49-60, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19836616

RESUMO

In 2005, the Azienda Ospedaliero-Universitaria of Trieste (AOUT) activated the hospital-based post-acute geriatric evaluation and management unit (PAGEMU). The purpose of the study is to illustrate the activities of the PAGEMU, and to evaluate the effects of personalized and multidisciplinary care on geriatric inpatients. The evaluation for admission in PAGEMU included general admitting criteria, co-morbidity, autonomy, and assessment of the patient's pre-morbid functional status. During the stay, inpatients completed their treatment plan, comprehensive geriatric assessment was carried out, and rehabilitation and nutritional interventions were implemented. If necessary, a new diagnostic-therapeutic plan was provided. A number of 826 patients were evaluated for admission in PAGEMU (612 patients from surgical departments and 214 from medical wards). The mean length of stay was 19.55 days. Re-evaluation of patients at discharge showed a statistically significant improvement in co-morbidity and in self-sufficiency, not in cognitive or mood status. PAGEMU is a valid model both for patient-oriented and for management-oriented objectives, shortening the length of stay in acute care settings and increasing hospital turnover.


Assuntos
Atenção à Saúde/normas , Avaliação Geriátrica/métodos , Serviços de Saúde para Idosos/tendências , Pacientes Internados , Instituições para Cuidados Intermediários/métodos , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Itália , Tempo de Internação/tendências , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
3.
Arch Gerontol Geriatr ; 49 Suppl 1: 83-94, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19836620

RESUMO

Remodeling of skeletal muscles is regulated by matrix metalloproteinases (MMPs). Functional genetic polymorphism (PM), modulating the expression of some MMPs, might be associated to different body composition and muscular strength improvement after exercise. Genetic PM of MMP-1 (G+/- at -1607), MMP-3 (5A/6A at -1171) and MMP-9 (Cytosine-Adenine microsatellite=(13-27)CA) repeats, around -90), body cell mass (BCM), extracellular water (ECW) and isometric maximal extensor strength (MES) of both legs were determined in 17 old sedentary women at the beginning and at the end of a 24 week physical exercise program. A 12 and 72% increase in BCM and MES, respectively, and 11% reduction in ECW were observed at the end of the program. Carriers of G-insertion in MMP-1, PM increased their BCM (7 kg vs. -1.5, p=0.007) and lost ECW (9% of total body water vs. 0.1%, p=0.004) more than the non-carriers; homozygote for 21 or less CA repeats/allele in MMP-9 PM gained more MES (115 N, interquartile range=IQR=63-132) than carriers of longer microsatellites (63 N, IQR=40-86, p=0.028). MMP-3 did not show any association with body composition and exercise-related strength changes. Exercise in elderly women increases BCM and strength, these changes are associate to specific MMP genotypes.


Assuntos
Envelhecimento/fisiologia , Composição Corporal/fisiologia , DNA/genética , Contração Isométrica/fisiologia , Metaloproteinases da Matriz/genética , Força Muscular/fisiologia , Polimorfismo Genético , Idoso , Teste de Esforço , Feminino , Genótipo , Humanos , Masculino , Metaloproteinase 1 da Matriz/biossíntese , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 3 da Matriz/biossíntese , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 9 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/genética , Metaloproteinases da Matriz/biossíntese , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
4.
Clin Nutr ; 28(4): 461-6, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19464772

RESUMO

Older subjects are at increased risk of partial or complete loss of independence due to acute and/or chronic disease and often of concomitant protein caloric malnutrition. Nutritional care and support should be an indispensable part of their management. Enteral nutrition is always the first choice for nutrition support. However, when patients cannot meet their nutritional requirements adequately via the enteral route, parenteral nutrition (PN) is indicated. PN is a safe and effective therapeutic procedure and age per se is not a reason to exclude patients from this treatment. The use of PN should always be balanced against a realistic chance of improvement in the general condition of the patient. Lower glucose tolerance, electrolyte and micronutrient deficiencies and lower fluid tolerance should be assumed in older patients treated by PN. Parenteral nutrition can be administered either via peripheral or central veins. Subcutaneous administration is also a possible solution for basic hydration of moderately dehydrated subjects. In the terminal, demented or dying patient the use of PN or hydration should only be given in accordance with other palliative treatments.


Assuntos
Geriatria , Desnutrição/terapia , Nutrição Parenteral , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Contraindicações , Nutrição Enteral , Geriatria/normas , Serviços de Assistência Domiciliar , Assistência Domiciliar , Instituição de Longa Permanência para Idosos , Humanos , Casas de Saúde , Estado Nutricional , Nutrição Parenteral/efeitos adversos , Nutrição Parenteral/normas , Qualidade de Vida
5.
G Ital Nefrol ; 25(3): 277-83, 2008.
Artigo em Italiano | MEDLINE | ID: mdl-18473297

RESUMO

Clinically compromised patients who must undergo chronic dialysis are, in general, at risk because the procedure can be difficult to perform and give poor results in terms of survival and of rehabilitation. However, it is dialysis of the very elderly which is routinely characterized by misgivings about the indication for and limits of the technique. Patients older than 75 years of age currently represent more than 35% of the population that begin dialysis in most European registries. In our center at least 30 very old patients begin dialysis every year, which represents 45% of the total incident patients. About 30% of these patients, because of severe physical and/or mental disability, often associated with a situation of social deprivation, rarely achieve true clinical stability and depend upon outside caregivers in order to survive. The treatment of these patients strains the resources of the health and social structure, as well as the Nephrology Division, whose organization can be disrupted by their urgent needs, such as hospitalization, transportation, convalescent care, etc. Despite these difficulties and a mean survival of only 28 months, the global clinical conditions of patients older than 75 years of age are not much different than patients in the age bracket of 65 to 75 years. In fact, excluding patients older than 85 years of age (a category which geriatricians consider separately), the survival and rehabilitation of the very elderly appear similar to those of patients 65 to 75 years of age. Many of the clinical problems of the dialyzed elderly, such as sensory, mental and functional impairment, are the result of advanced age per se rather than of uremia or of dialysis. Therefore, ethical considerations of dialysis and of health maintenance in the very elderly are similar to those presented by patients who are afflicted by other serious diseases such as cancer, heart failure, or extensive stroke. As a result of modern technology and the advancement of our clinical knowledge, it is difficult to conceive of a true motive to not dialyze a patient--whether very elderly or any other patient in critical conditions--except in situations of futility or the impossibility to attain a reasonable quality of life. Thus, the true nature of the debate regarding the indications or the limits of dialysis in developed countries is not economic, technical nor clinical, but ethical. The challenge for the Nephrologist is to balance the need to alleviate human suffering and the institutional support that society can offer, which is the "bottom line" which unifies dialysis for the very elderly with every other therapy which prolongs life in tenuous conditions.


Assuntos
Envelhecimento , Falência Renal Crônica/terapia , Diálise Renal/ética , Idoso , Idoso de 80 Anos ou mais , Humanos , Expectativa de Vida , Seleção de Pacientes/ética , Qualidade de Vida , Diálise Renal/métodos , Fatores de Risco , Análise de Sobrevida
6.
Clin Nutr ; 26(1): 123-32, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16938366

RESUMO

AIM: To determine the prevalence (cases per million inhabitants) of home artificial nutrition (HAN), enteral (HEN) and parenteral (HPN), in Italy, grouped according to administrative regions, patient age and primary disease, and to analyze the impact both of the presence of an HAN regional regulation and of demographic characteristics. METHODS: In April 2005, the Regional Coordinators of the Italian Society for Parenteral and Enteral Nutrition (SINPE) recorded all the ongoing cases of HAN using a structured questionnaire and were asked to estimate the representativeness of the collected sample with respect to the total expected HAN. RESULTS: A total of 6955 cases of HAN (93.5% adults, 6.5% pediatric patients < or = 18 years) were recorded in 16 of the 20 Italian regions (80% of the Italian population; sample representativeness 78%). HAN prevalence 152.6 (83.9% HEN, 16.1% HPN); the HAN range among the regions was: prevalence 28.1-519.8; oncological disease 13.8-75.7%, neurological disease 15.5-79.9%, intestinal failure 1.3-14.0%. An HAN regulation was present in 11 regions. A positive association (P=0.012) was found between the number of years since the regulation was issued and the HAN prevalence, and also between the % neurological patients and the population density (P=0.130) and the % inhabitants > or = 75 years (P=0.040). CONCLUSIONS: The need for HAN regards a great number of patients throughout the country; there are substantial differences between the regions with respect to both the prevalence and the use of HAN in various disease categories. A specific regulation may favor the development of HAN.


Assuntos
Nutrição Enteral/estatística & dados numéricos , Enteropatias/terapia , Neoplasias/terapia , Doenças do Sistema Nervoso/terapia , Nutrição Parenteral no Domicílio/estatística & dados numéricos , Adulto , Criança , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Itália/epidemiologia , Masculino , Prevalência , Inquéritos e Questionários
7.
Clin Nutr ; 25(2): 295-310, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16697495

RESUMO

Enteral nutrition (EN) by means of oral nutritional supplements (ONS) and tube feeding (TF) offers the possibility of increasing or ensuring nutrient intake in cases where normal food intake is inadequate. These guidelines are intended to give evidence-based recommendations for the use of ONS and TF in nephrology patients. They were developed by an interdisciplinary expert group in accordance with officially accepted standards and are based on all relevant publications since 1985. They were discussed and accepted in a consensus conference. Because of the nutritional impact of renal diseases, EN is widely used in nephrology practice. Patients with acute renal failure (ARF) and critical illness are characterized by a highly catabolic state and need depurative techniques inducing massive nutrient loss. EN by TF is the preferred route for nutritional support in these patients. EN by means of ONS is the preferred way of refeeding for depleted conservatively treated chronic renal failure patients and dialysis patients. Undernutrition is an independent factor of survival in dialysis patients. ONS was shown to improve nutritional status in this setting. An increase in survival has been recently reported when nutritional status was improved by ONS.


Assuntos
Nutrição Enteral/normas , Gastroenterologia/normas , Padrões de Prática Médica/normas , Insuficiência Renal/terapia , Europa (Continente) , Humanos
8.
G Ital Nefrol ; 21(6): 554-60, 2004.
Artigo em Italiano | MEDLINE | ID: mdl-15593023

RESUMO

A new category of patients aged >75 yrs, namely the elderly, is now being freely admitted to hemodialysis (HD) and this category is becoming predominant. The absence of systematic studies makes this patient category almost indistinguishable from other categories, even though its peculiarity is now evident. At least 30-40% of individuals in this age bracket are expected to be dependent and/or frail, but the incidence of frailty is likely to be higher in the elderly undergoing HD. Due to severe physical and/or mental impairment and often because of strong social hardships, these patients rarely experience clinical stability and are dependent on third parties for their survival. Their care produces complex problems for welfare services and this has proved responsible for modifying the organization of renal care units. These repeated patient admissions to hospital are filling nephrology facilities, and the dialysis management -- mainly concerning outpatients -- requires a much greater use of facilities and staff than normal if compared to average dialysis patients. In 112 elderly patients consecutively admitted to the dialysis program over a period of 10 yrs, we identified 35 dependent or frail patients (31.2%), even taking into consideration only extreme degrees of infirmity. Dependence proved to be the only clinical parameter associated with survival (mortality at 6 months 23.6 vs. 10.6%, p<0.01; Kaplan-Meier survival curves, p<0.03 log-rank test), while comorbidities -- in particular cardiovascular -- that usually affect dialysis mortality rates, did not seem to be discriminating risk factors in the elderly. More precisely, with the confirmation of these data through wider case studies, the idea will be reinforced that, also in dialysis, the elderly must be constantly monitored for dependence and frailty, as is the case in any exclusively geriatric field. Prevention, as well as a therapeutic approach specifically modeled on these conditions, could help to improve the prognosis of this patient category, which is particularly difficult to deal with and is becoming predominant in dialysis units.


Assuntos
Idoso Fragilizado , Diálise Renal , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Idoso Fragilizado/estatística & dados numéricos , Humanos , Diálise Renal/mortalidade , Diálise Renal/normas , Diálise Renal/estatística & dados numéricos , Fatores de Risco , Fatores Socioeconômicos , Taxa de Sobrevida
9.
Clin Nutr ; 21(5): 373-8, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12381333

RESUMO

BACKGROUND & AIMS: The lysosomal cathepsin system contributes to degrading cellular skeletal muscle proteins in many catabolic diseases. We have assessed the relationships between cathepsin B mRNA levels and the enzyme activity for this protease in the skeletal muscle of acutely ill patients with severe trauma (n=7) and in patients with a variety of chronic disease states (hemodialysis, n=3; nervous anorexia, n=1; type 2 diabetes, n=2; prolonged immobilization, n=1). METHODS: Muscle biopsies were taken from the vastus lateralis muscle in patients and controls to assess tissue levels of cathepsin B mRNA by competitive-quantitative polymerase chain reaction, cathepsin B proteolytic activity and myofibrillar protein content as alkali-soluble protein to DNA ratio (ASP/DNA). In the trauma patients, muscle protein loss was assessed by the arteriovenous balance technique as rate of phenylalanine release from leg muscle. RESULTS: The acute trauma patients exhibited a significant net phenylalanine release from leg muscle (33+/-4 nmol phenylalanine/min/100 ml leg volume) despite a continuous nutritional support. The muscle ASP/DNA ratio was lower (P<0.05) in the patients with chronic diseases (383+/-33) than in groups of healthy controls (554+/-41) or of uncomplicated, moderately obese subjects (525+/-26). Cathepsin B mRNA levels were 6-10 times greater (P<0.05) in the patients with acute trauma or chronic catabolic diseases than in the healthy subjects. Cathepsin B enzymatic activity were 2-3 times greater (P<0.05) in the chronic and acute patients than in the group of uncomplicated, moderately obese subjects. Regression analysis between cathepsin B mRNA and cathepsin B enzymatic activity indicates a significant direct correlation (r=0.84; P<0.05) in the chronic catabolic conditions, but not in the acute trauma patients (r=-0.05). CONCLUSIONS: In skeletal muscle of patients with stable chronic catabolic diseases, cathepsin B activity is directly related to cathepsin B mRNA levels, suggesting that in these patients this enzyme could be mainly regulated at the level of gene transcription.


Assuntos
Catepsina B/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Desnutrição Proteico-Calórica/enzimologia , Desnutrição Proteico-Calórica/patologia , Análise de Variância , Biópsia por Agulha , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Apoio Nutricional , Fenilalanina/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Análise de Regressão
10.
Metabolism ; 50(1): 19-23, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11172469

RESUMO

To determine the influence of body fat distribution on kinetic aspects of insulin action, we have monitored the rate of increase of glucose infusion during 6-hour hyperinsulinemic (40 mU/m2/min) euglycemic clamps in 10 patients with upper body obesity (body mass index [BMI], 41 +/- 3 kg/m2; waist-to-hip ratio [WHR], > 1.00 for men and > 0.85 for women), 12 patients with lower body obesity (BMI, 40 +/- 2 kg/m2; WHR, < 1.00 for men and < 0.85 for women), and 5 control subjects (BMI, < 30 kg/m2; WHR, < 1.00 for men and < 0.85 for women). In all subjects, glucose infusion rate (GIR) to maintain euglycemia increased during the clamp studies to achieve maximal, steady state values after the fourth to fifth hour. During the first 2 hours of clamp, mean GIR (GIR20-120min) (traditional approach to assess insulin sensitivity) was lower (P < 0.05) in the upper body obesity group than in the lower body obesity group (2.12 +/- 0.14 and 3.03 +/- 0.33 mg/kg per min, respectively). In contrast, the maximal steady-state GIR (GIRMAX) (calculated as mean GIR during the sixth hour of clamp) was similar in the upper body and in the lower body obesity groups (4.48 +/- 0.45 and 4.57 +/- 0.36 mg/kg per min, respectively). Control subjects exhibited higher values of both GIR20-120min and GIRMAX (5.57 +/- 0.67 and 7.05 +/- 0.59 mg/kg per min, respectively) than those of both groups of obese patients. The time to reach half-maximal GIR (T1/2) was greater (P < .05) in the upper body obesity (94 +/- 12 min) than that in the lower body obesity (41 +/- 5 min) and in the control group (30 +/- 5 min). In pooled subjects, BMI correlated with GIRMAX (n = 27, R = -.75, P < .001), but not with T1/2 (R = .21). Similarly, whole body percent fat mass, as assessed by bioelectrical impedance analysis, correlated with GIRMAX (n = 16, R = -.79, P < .001), but not with T1/2 (R = .10). In contrast, WHR closely correlated with T1/2 (n = 27, R = .78, P < .001), but not with GIRMAX (R = .11). We conclude that upper body obesity is associated with a slower rate of activation of insulin action on glucose metabolism, whereas total body adiposity selectively affects the maximal, steady-state insulin effect.


Assuntos
Insulina/metabolismo , Obesidade/fisiopatologia , Constituição Corporal , Índice de Massa Corporal , Impedância Elétrica , Feminino , Técnica Clamp de Glucose , Humanos , Hipertensão/etiologia , Resistência à Insulina/fisiologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações
13.
Am J Physiol Endocrinol Metab ; 279(2): E323-32, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10913032

RESUMO

We determined the effects of 24-h recombinant human growth hormone (rhGH) infusion into a femoral artery on leg muscle protein kinetics, amino acid transport, and glutamine metabolism in eight adult hypercatabolic trauma patients. Metabolic pathways were assessed by leg arteriovenous catheterization and muscle biopsies with the use of stable amino acid isotopes. Muscle mRNA levels of selected enzymes were determined by competitive PCR. rhGH infusion significantly accelerated the inward transport rates of phenylalanine and leucine and protein synthesis, whereas the muscle protein degradation rate and cathepsin B and UbB polyubiquitin mRNA levels were not significantly modified by rhGH. rhGH infusion decreased the rate of glutamine de novo synthesis and glutamine precursor availability, total branched-chain amino acid catabolism, and nonprotein glutamate utilization. Thus net glutamine release from muscle into circulation significantly decreased after rhGH administration ( approximately 50%), whereas glutamine synthetase mRNA levels increased after rhGH infusion, possibly to compensate for reduced glutamine precursor availability. We conclude that, after trauma, the anticatabolic action of rhGH is associated with a potentially harmful decrease in muscle glutamine production.


Assuntos
Glutamina/metabolismo , Hormônio do Crescimento Humano/sangue , Traumatismo Múltiplo/metabolismo , Músculo Esquelético/metabolismo , Biossíntese de Proteínas , Redução de Peso/fisiologia , Adulto , Aminoácidos/sangue , Biopolímeros/genética , Biopolímeros/metabolismo , Biópsia , Catepsina B/genética , Catepsina B/metabolismo , Nutrição Enteral , Feminino , Glutamato-Amônia Ligase/genética , Glutamato-Amônia Ligase/metabolismo , Hormônio do Crescimento Humano/administração & dosagem , Humanos , Infusões Intra-Arteriais , Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Perna (Membro)/irrigação sanguínea , Perna (Membro)/fisiologia , Masculino , Traumatismo Múltiplo/patologia , Traumatismo Múltiplo/terapia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Nutrição Parenteral , Poliubiquitina , RNA/metabolismo , Ubiquitinas/genética , Ubiquitinas/metabolismo , Redução de Peso/efeitos dos fármacos
14.
Metabolism ; 49(6): 689-91, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10877190

RESUMO

The influence of the gene expression of critical components of the cytoplasmic and lysosomal proteolytic pathways on the rate of protein degradation was evaluated in the leg skeletal muscle of 8 severely traumatized patients. Muscle proteolysis was determined as the intramuscular phenylalanine rate of appearance by L-[ring-2H5]phenylalanine infusion and the leg arteriovenous catheterization technique combined with muscle biopsy. Muscle mRNA levels of UbB polyubiquitin and cathepsin B were determined by reverse transcriptase-competitive polymerase chain reaction and expressed as a percent of the mRNA level of the housekeeping gene glyceraldehyde-3-phosphate dehydrogenase (GAPDH). In the patients, individual values for UbB polyubiquitin mRNA levels directly correlated with the rate of muscle proteolysis (r = .76, P < .05), whereas no correlation (r = .10) was found between cathepsin B mRNA levels and proteolysis. Thus, after trauma, the rate of muscle proteolysis appears to be largely regulated by the ubiquitin-proteasome system at the level of gene transcription.


Assuntos
Biopolímeros/metabolismo , Cisteína Endopeptidases/metabolismo , Complexos Multienzimáticos/metabolismo , Músculo Esquelético/enzimologia , Ubiquitinas/metabolismo , Ferimentos e Lesões/enzimologia , Adulto , Biopolímeros/genética , Catepsina B/genética , Catepsina B/metabolismo , Regulação da Expressão Gênica , Humanos , Masculino , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Fenilalanina/metabolismo , Poliubiquitina , Complexo de Endopeptidases do Proteassoma , RNA Mensageiro/metabolismo , Transcrição Gênica , Ubiquitinas/genética , Ferimentos e Lesões/genética
16.
J Hypertens ; 16(12 Pt 1): 1783-8, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9869012

RESUMO

OBJECTIVE: To determine whether kinetic abnormalities in the onset of insulin action contribute to the insulin resistance in obesity-associated hypertension. DESIGN: We monitored the rate of increase in glucose infusion during 6 h of hyperinsulinemic (40 mU/m2 per min) euglycemic clamps in hypertensive and normotensive obese subjects. The two groups of hypertensive (n=9) and normotensive (n=9) subjects were matched for age (48+/-2 versus 45+/-5 years), sex (five males and four females versus four males and five females) and body mass index (42+/-3 versus 40+/-2 kg/m2). RESULTS: In all subjects, the glucose infusion rate required to maintain euglycemia increased progressively during the clamp studies to achieve maximal, steady-state values within the fifth hour. During the first 2 h of the clamp, mean glucose infusion rate, the traditional approach to assessing insulin sensitivity, was lower in the hypertensive than in the normotensive obese patients (2.04+/-0.13 versus 3.29+/-0.41 mg/kg per min, respectively; P < 0.05). In contrast, the maximal steady-state glucose infusion rate, calculated as the mean value during the sixth hour of clamping, was similar in the hypertensive and in the normotensive obese patients (4.48+/-0.43 versus 4.81+/-0.45 mg/kg per min, respectively; NS). The time required to reach the half-maximal glucose infusion rate was greater in the hypertensive than normotensive obese patients (91+/-12 versus 38+/-5 min, respectively; P< 0.05). CONCLUSION: In obesity, hypertension was associated with a slower rate of activation of the insulin effect on glucose metabolism, whereas the maximal steady-state insulin effects were not altered by elevated blood pressure. Thus, the link between obesity and hypertension may be associated with the kinetics of onset of insulin action.


Assuntos
Hipertensão/metabolismo , Insulina/fisiologia , Obesidade/metabolismo , Adulto , Idoso , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Feminino , Glucose/efeitos adversos , Técnica Clamp de Glucose , Humanos , Hiperinsulinismo/induzido quimicamente , Hipertensão/fisiopatologia , Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Obesidade/fisiopatologia
17.
Miner Electrolyte Metab ; 24(4): 267-72, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9554566

RESUMO

To investigate the relationship between decline in renal function and alterations of protein metabolism we determined the rate of whole-body protein turnover in a group of 15 postabsorptive chronically uremic patients (9 males and 6 females) with different levels of serum creatinine concentrations (average 5.7 +/- 0.4 (SE) mg x dl(-1); range 3.3-9.1). Patients' age and body mass index were 53 +/- 4 years (range 26-73) and 24.7 +/- 0.6 kg/m2 (range 20.3-28.7), respectively. Nutritional status (plasma albumin 3.6 +/- 0.4 g x dl[-1]) and acid-base equilibrium (arterial pH 7.38 +/- 0.01) were fairly controlled by therapy. Whole-body leucine rate of appearance (Ra), an index of whole-body protein turnover, was assessed using a stable isotope technique. L-[1-(13)C]leucine was continuously infused and plasma [1-(13)C]alpha-ketoisocaproic acid enrichment was determined in steady-state conditions as a marker of the intracellular leucine enrichment. The average leucine Rawas 2.03 +/- 0.13 micromol x kg(-1) x min(-1) (range 1.29-3.19). Using simple linear regression analysis, the coefficient of correlation between the individual values of serum creatinine concentration and leucine Ra was 0.59 (n = 15; p = 0.02). Leucine Ra did not significantly correlate with blood pH or plasma albumin. In conclusion, we found a positive linear relationship between the values of plasma creatinine concentration and the rate of whole-body protein degradation. This correlation suggests that the progression of renal insufficiency is associated with accelerated rates of turnover of body proteins.


Assuntos
Creatinina/sangue , Falência Renal Crônica/metabolismo , Proteínas/metabolismo , Adulto , Idoso , Índice de Massa Corporal , Isótopos de Carbono , Feminino , Humanos , Concentração de Íons de Hidrogênio , Cetoácidos/metabolismo , Cinética , Leucina/metabolismo , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Análise de Regressão , Uremia/metabolismo
18.
Curr Opin Clin Nutr Metab Care ; 1(1): 91-5, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10565336

RESUMO

Malnutrition and protein wasting are common features of chronically uremic patients, whether on conservative or dialysis treatment. Optimization of protein-energy intake is difficult because of anorexia, catabolic factors (acidosis, insulin resistance, cytokines, etc.) and intercurrent infections. The use of growth hormone may improve the efficiency of dietary protein utilization. Evidence suggests a small but appreciable effect of very low protein diets on progression of renal insufficiency.


Assuntos
Dieta com Restrição de Proteínas , Falência Renal Crônica/terapia , Apoio Nutricional , Aminoácidos/administração & dosagem , Ingestão de Energia , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Falência Renal Crônica/complicações , Distúrbios Nutricionais/etiologia , Uremia/complicações , Uremia/terapia , Síndrome de Emaciação/etiologia
19.
Kidney Int Suppl ; 62: S41-4, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9350678

RESUMO

The pathogenesis of protein wasting in chronic renal failure is multifactorial. Potential mediators of protein catabolism in chronic uremia include anorexia, low protein-energy intake, increased cortisol and parathyroid hormone secretion, insulin resistance, metabolic acidosis and unidentified uremic toxins. In non-acidotic uremic patients the rate of protein turnover (that is, synthesis and degradation) has often been found to be decreased. Malnutrition also decreases both protein synthesis and degradation. In contrast, during acidosis protein degradation is primarily accelerated and results in rapid loss of body proteins. Cytokine concentrations have often been found increased in both dialyzed and undialyzed chronically uremic patients. Our study determined the circulating levels of TNF-alpha and of type I (60 kDa) and type II (80 kDa) soluble TNF-alpha receptors in undialyzed uremic patients, and found that their plasma levels were greatly increased. Serum creatinine correlated with TNF-alpha soluble receptors but not with the TNF-alpha. Thus, TNF-alpha is potentially an important mediator of protein wasting in chronically uremic patients. Pharmacological therapy of protein catabolism in chronic uremia may include the administration of pentoxifylline, which has been shown to decrease protein degradation by interfering with the TNF-alpha system (that is, TNF-alpha and its soluble receptors) in experimental models. Growth hormone and insulin-like growth factor-1 administration may also be beneficial in these patients, but further evaluation of the hormone effects on glucose and glutamine metabolism is called for.


Assuntos
Desnutrição Proteico-Calórica/fisiopatologia , Uremia/fisiopatologia , Adulto , Creatinina/sangue , Feminino , Humanos , Falência Renal Crônica/complicações , Falência Renal Crônica/metabolismo , Masculino , Pessoa de Meia-Idade , Desnutrição Proteico-Calórica/etiologia , Desnutrição Proteico-Calórica/metabolismo , Receptores do Fator de Necrose Tumoral/sangue , Fator de Necrose Tumoral alfa/metabolismo , Uremia/metabolismo
20.
Nutrition ; 13(9 Suppl): 52S-57S, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9290110

RESUMO

The metabolic response to trauma and sepsis involves an increased loss of body proteins. Specific sites of changes of protein and amino acid metabolism have been identified. In skeletal muscle, the rate of proteolysis is accelerated greatly. The rate of protein synthesis also may be increased but not enough to match the increase in degradation. Intramuscular glutamine concentration is decreased because of increased efflux and possibly decreased de novo synthesis. In the liver, the rate of synthesis of selected proteins (i.e., albumin, transferrin, prealbumin, retinol-binding protein, and fibronectin) is decreased, whereas acute phase protein synthesis is accelerated. Tissues characterized by rapidly replicating cells, such as enterocytes, immune cells, granulation tissue, and keratinocytes, exhibit early alterations in the case of decreased protein synthesis capacity. In these tissues, glutamine use is accelerated. Increased stress hormone (cortisol and glucagon) and cytokine secretion, as well as intracellular glutamine depletion, are potential mediators of altered protein metabolism in trauma and sepsis. However, the relative importance of these factors has not been clarified. Therapy of acute protein catabolism may include the use of biosynthetic human growth hormone, possibly in combination with insulin-like growth factor-1, and the administration of metabolites at pharmacologic doses. We recently studied the effects of carnitine and alanyl-glutamine administration in severely traumatized patients. We found that both carnitine and the glutamine dipeptide restrained whole-body nitrogen loss without affecting selected indices of protein metabolism in the skeletal muscle.


Assuntos
Proteínas/metabolismo , Sepse/metabolismo , Ferimentos e Lesões/metabolismo , Carnitina/uso terapêutico , Dipeptídeos/uso terapêutico , Humanos , Apoio Nutricional , Sepse/terapia , Ferimentos e Lesões/terapia
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