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1.
Hernia ; 26(5): 1325-1336, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36088435

RESUMO

BACKGROUND: Lateral abdominal wall hernias (LAWH) constitute about 1-4% of hernia surgical procedures. They represent a unique surgical challenge on account of their potential for anatomical complexity and consequent operative technical demand. Furthermore, LAWH repairs are currently not standardized, and remain contentious, despite a variety of approaches. These repairs are attendant with not insignificant morbidity and recurrence rates. We profile here our endoscopic and hybrid surgical approach to the management of LAWH and early therapeutic outcomes. METHODS: A retrospective review of our hernia clinical database between March 2018 and December 2020 was performed to extract all LAWH (with and without an associated midline component) patients, who underwent an enhanced-view totally extra peritoneal (eTEP) hernia repair with a transversus abdominis release (TAR), or a hybrid repair. Initial outcome data (6-month follow-up) is profiled here. The primary outcome measures were hernia recurrence and hernia-site bulging. The secondary measures were surgical site occurrence (SSO) and hernia-related quality of life (QoL). RESULTS: A total of 33 LAWH patients underwent an eTEP TAR or hybrid hernia repair. 11 patients had an associated midline defect and 12 were recurrent hernias. The mean hernia defect area was 84.2 ± 49 cm2 and mean mesh size was 859.6 ± 263 cm2. There was no hernia recurrence at initial follow-up of 24 months. The SSO rate was 12%. The CCS QoL scores were 34.6 ± 2 pre-operatively, and improved to 27.2 ± 4 at 6 months. CONCLUSIONS: Our endoscopic and hybrid technique is a safe, reproducible, and technically promising approach for the repair of LAWH. Thorough knowledge of the surgical anatomy of the lateral abdominal wall and advanced endosurgical skills are imperative for good outcomes. We await the long-term results of our LAWH cohort to confirm the findings.


Assuntos
Parede Abdominal , Hérnia Ventral , Hérnia Incisional , Músculos Abdominais/cirurgia , Parede Abdominal/cirurgia , Hérnia Ventral/cirurgia , Herniorrafia/efeitos adversos , Herniorrafia/métodos , Humanos , Hérnia Incisional/cirurgia , Qualidade de Vida , Recidiva , Estudos Retrospectivos , Telas Cirúrgicas
3.
Hernia ; 25(6): 1635-1646, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33826031

RESUMO

INTRODUCTION: The Enhanced-View Totally Extra Peritoneal Rives-Stoppa (e-TEP-RS) Technique for the repair of large, complex, ventral abdominal hernias has gained popularity especially in overcoming the disadvantages with Intra Peritoneal Onlay Mesh (IPOM) repairs and to enable siting of a large prosthetic mesh in an anatomical plane distinct from the abdominal cavity and its contents. Evolving variations of the original technique have allowed the definitive repair of such defects in a reproducible manner. We present our initial experience of this approach and detailed steps of our native technical modifications in overcoming the challenges in performing this complex and potentially challenging procedure. MATERIALS AND METHODS: This is a retrospective review of the clinical data of midline, large, complex, ventral abdominal hernia patients who underwent e-TEP-RS with and without Transversus Abdominis Release (TAR). Patients, with or without Diastasis of Rectus Abdominis Muscle (DRAM) were included. Key outcomes measured were post-operative pain, operative morbidity, readmission, Quality of Life (QoL), hernia recurrence. RESULTS: A total of 58 midline, ventral abdominal hernia patients who underwent e-TEP-RS with and without Transversus Abdominis Release (TAR), between March 2018 and December 2019 were studied. Mean defect area was 41.0 ± 28 cm2 and the mean mesh surface area was 473.5 ± 165 cm2. e-TEP-RS was done in 35 cases, e-TEP RS TAR in 15 cases and e-TEP-RS with e-TEP inguinal in 08 cases. There was no intraoperative morbidity. Mean duration of surgery was 156.2 ± 40 min and mean blood loss was 40.5 ± 26 cc. The CCS QoL scores improved from 34.6 (± 2) pre-operatively to 27.2 (± 4) at the end of 6 months. One patient had a supra-umbilical recurrence following bilateral TAR over the superior edge of the mesh. Follow-up ranged from 6 to 22 months, with a mean of 14 months. Major complications (n = 12; 20.7%) were seroma formation and prolonged ileus. CONCLUSION: The e-TEP-RS technique for large, complex, midline, ventral abdominal hernias can be used with excellent results and acceptable morbidity. This technique is technically challenging and should be mastered in relatively smaller ventral hernias to achieve good results before attempting it in larger, complex ones.


Assuntos
Hérnia Ventral , Hérnia Incisional , Laparoscopia , Hérnia Ventral/cirurgia , Herniorrafia/efeitos adversos , Herniorrafia/métodos , Humanos , Hérnia Incisional/cirurgia , Laparoscopia/métodos , Qualidade de Vida , Recidiva , Estudos Retrospectivos , Telas Cirúrgicas
4.
Eur J Clin Nutr ; 70(6): 687-93, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26373967

RESUMO

BACKGROUND/OBJECTIVES: Multi-nutrient insufficiencies as a consequence of nutritional and economic factors are common in India and other developing countries. We have examined the impact of multi-nutrient insufficiency on markers of one carbon (1C) metabolism in the blood, and response to a methionine load in clinically healthy young women. SUBJECTS/METHODS: Young women from Pune, India (n=10) and Cleveland, USA (n=13) were studied. Blood samples were obtained in the basal state and following an oral methionine load (50 mg/kg of body weight in orange juice). Plasma concentrations of vitamin B12, folate and B6 were measured in the basal state. The effect of methionine load on the levels of methionine, total homocysteine, cysteine, glutathione and amino acids was examined. RESULTS: Indian women were significantly shorter and lighter compared with the American women and had lower plasma concentration of vitamins B12, folate and B6, essential amino acids and glutathione, but higher concentration of total homocysteine. The homocysteine response to methionine load was higher in Indian women. The plasma concentrations of glycine and serine increased in the Indian women after methionine (in juice) load. A significant negative correlation between plasma B6 and homocysteine (r= -0.70), and plasma folate and glycine and serine levels were observed in the Indian group (P<0.05) but not in the American group. CONCLUSIONS: Multi-nutrient insufficiency in the Indian women caused unique changes in markers of whole body protein and 1C metabolism. These data would be useful in developing nutrient intervention strategies.


Assuntos
Desnutrição/sangue , Metionina/administração & dosagem , Adulto , Aminoácidos/sangue , Biomarcadores/sangue , Estatura , Carbono/metabolismo , Feminino , Ácido Fólico/sangue , Alimentos , Glutationa/sangue , Homocisteína/sangue , Humanos , Índia , Desnutrição/fisiopatologia , Metionina/sangue , Ohio , Vitamina B 12/sangue , Complexo Vitamínico B/sangue
8.
J Dev Orig Health Dis ; 4(2): 121-33, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25054678

RESUMO

Contemporary clinical practice for the care of the prematurely born babies has markedly improved their rates of survival so that most of these babies are expected to grow up to live a healthy functional life. Since the clinical follow-up is of short duration (years), only limited data are available to relate non-communicable diseases in adult life to events and interventions in the neonatal period. The major events that could have a programming effect include: (1) intrauterine growth restriction; (2) interruption of pregnancy with change in redox and reactive oxygen species (ROS) injury; (3) nutritional and pharmacological protocols for clinical care; and (4) nutritional care in the first 2 years resulting in accelerated weight gain. The available data are discussed in the context of perturbations in one carbon (methyl transfer) metabolism and its possible programming effects. Although direct evidence for genomic methylation is not available, clinical and experimental data on impact of redox and ROS, of low protein intake, excess methionine load and vitamin A, on methyl transfers are reviewed. The consequences of antenatal and postnatal administration of glucocorticoids are presented. Analysis of the correlates of insulin sensitivity at older age, suggests that premature birth is the major contributor, and is compounded by gain in weight during infancy. We speculate that premature interruption of pregnancy and neonatal interventions by affecting one carbon metabolism may cause programming effects on the immature baby. These can be additive to the effects of intrauterine environment (growth restriction) and are compounded by accelerated growth in early infancy.

9.
J Pediatr Gastroenterol Nutr ; 50(1): 85-91, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19881390

RESUMO

The number of surviving children born prematurely has increased substantially during the last 2 decades. The major goal of enteral nutrient supply to these infants is to achieve growth similar to foetal growth coupled with satisfactory functional development. The accumulation of knowledge since the previous guideline on nutrition of preterm infants from the Committee on Nutrition of the European Society of Paediatric Gastroenterology and Nutrition in 1987 has made a new guideline necessary. Thus, an ad hoc expert panel was convened by the Committee on Nutrition of the European Society of Paediatric Gastroenterology, Hepatology, and Nutrition in 2007 to make appropriate recommendations. The present guideline, of which the major recommendations are summarised here (for the full report, see http://links.lww.com/A1480), is consistent with, but not identical to, recent guidelines from the Life Sciences Research Office of the American Society for Nutritional Sciences published in 2002 and recommendations from the handbook Nutrition of the Preterm Infant. Scientific Basis and Practical Guidelines, 2nd ed, edited by Tsang et al, and published in 2005. The preferred food for premature infants is fortified human milk from the infant's own mother, or, alternatively, formula designed for premature infants. This guideline aims to provide proposed advisable ranges for nutrient intakes for stable-growing preterm infants up to a weight of approximately 1800 g, because most data are available for these infants. These recommendations are based on a considered review of available scientific reports on the subject, and on expert consensus for which the available scientific data are considered inadequate.


Assuntos
Nutrição Enteral , Fórmulas Infantis , Recém-Nascido Prematuro , Leite Humano , Necessidades Nutricionais , Ingestão de Energia , Alimentos Fortificados , Gastroenterologia/métodos , Humanos , Recém-Nascido , Pediatria/métodos , Obras Médicas de Referência
10.
Diabetologia ; 49(7): 1677-85, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16752186

RESUMO

AIMS/HYPOTHESIS: Adiponectin is upregulated during adipogenesis and downregulated in insulin-resistant states. The mechanism(s) governing the re-arrangements from adipogenesis to facilitated lipolysis during pregnancy are unknown. Our purpose was to analyse the role of adiponectin relative to the metabolic changes in human pregnancy. SUBJECTS, MATERIALS AND METHODS: Lean women (BMI <25 kg/m(2)) were evaluated longitudinally before conception, and in early (12-14 weeks) and late (34-36 weeks) pregnancy. Insulin sensitivity was measured using the glucose clamp technique. Venous blood and subcutaneous adipose tissue biopsies were obtained at each time point. RESULTS: Adiponectin concentrations were lower in the third trimester than in the pregravid condition (9.9+/-1.4 vs 13.5+/-1.8 microg/ml). The hypoadiponectinaemia was reflected by a 2.5-fold decrease in white adipose tissue adiponectin mRNA. These changes were associated with a 25% increase in fat mass (23.7+/-2.9 vs 18.9+/-2.9 kg). Insulin infusion decreased high molecular weight adiponectin complexes in pregravid women (9.9+/-0.6 vs 6.2+/-0.06) and the suppressive effect of insulin was lost during pregnancy. The pregnancy-mediated changes in adiponectin were strongly correlated with basal insulin levels and insulin sensitivity (p<0.0001). The relationship between adiponectin and insulin sensitivity was related to the decreased insulin regulation of glucose utilisation (r=0.55, p<0.001) but not of endogenous hepatic glucose production. CONCLUSIONS/INTERPRETATION: These data demonstrate that pregnancy is associated with adiponectin changes in lean women. Hypoadiponectinaemia is reflected by a lower amount of high molecular weight adiponectin and by the ratio of high to low molecular weight multimers. The adiponectin changes relate to decreased insulin sensitivity of glucose disposal rather than alterations of lipid metabolism.


Assuntos
Adiponectina/fisiologia , Glucose/metabolismo , Metabolismo dos Lipídeos , Gravidez/metabolismo , Adiponectina/sangue , Glicemia/análise , Metabolismo Energético , Feminino , Idade Gestacional , Técnica Clamp de Glucose , Humanos , Insulina/sangue , Insulina/farmacologia , Gravidez/sangue
11.
Ann Pharmacother ; 35(11): 1381-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11724088

RESUMO

OBJECTIVE: To describe the fifth case of clozapine-induced diabetic ketoacidosis (DKA) with complete resolution of abnormal glucose metabolism after discontinuation of clozapine as assessed by oral glucose tolerance testing (OGTT) and the first to be serially studied with markers of pancreatic autoimmunity; to demonstrate insulin resistance using the euglycemic clamp study and reduced pancreatic insulin reserve using intravenous glucose tolerance testing (IVGTT) in clozapine-induced diabetes mellitus and DKA, when the OGTT was normal; and to systematically review the previously described cases of clozapine-induced diabetes mellitus and DKA. CASE SUMMARY: A 33-year-old white man without past or family history of diabetes mellitus presented with DKA after eight months of clozapine therapy (50 mg twice daily). After treatment of DKA and discontinuation of clozapine, glucose tolerance and concurrent serum insulin concentrations reverted to normal as measured by two OGTT performed 60 and 320 days after resolution of DKA. DISCUSSION: Antiislet-cell antibodies, antiglutamic acid decarboxylase antibodies, and human insulin antibody were negative on two separate occasions. Euglycemic clamp study demonstrated insulin resistance manifested by a glucose disposal rate of approximately 55% of mean normal values. IVGTT demonstrated a low rate of glucose disappearance (KG = 0.95) and diminished first-phase insulin response when OGTT was normal, indicating impairment in insulin sensitivity and reduction in beta cell function 323 days after discontinuance of clozapine. This adverse reaction is considered probable according to the Naranjo probability scale. CONCLUSIONS: The occurrence of cases of DKA and new or worsening diabetes mellitus in patients using clozapine suggests a causal relationship. We hypothesize that the mechanism by which clozapine may produce glucose intolerance may require a preexisting latent defect in insulin secretion and insulin action. With the administration of clozapine, some of these patients may develop worsening insulin resistance and may fail to mount an appropriate compensatory beta cell insulin secretion for the degree of insulin resistance. As a consequence, hyperglycemia develops and its persistence results in glucose toxicity, further suppressing beta cell insulin secretion. Such combined defects in insulin secretion and sensitivity are known to be synergistic, leading to the development of abnormal glucose tolerance, which can be clinically manifested as a spectrum ranging from impaired glucose tolerance through severe hyperglycemia to DKA. Patients being started on clozapine should be carefully followed for the development or worsening of diabetes mellitus, regardless of the dose of the drug.


Assuntos
Antipsicóticos/efeitos adversos , Clozapina/efeitos adversos , Cetoacidose Diabética/induzido quimicamente , Cetoacidose Diabética/diagnóstico , Técnica Clamp de Glucose , Adulto , Antipsicóticos/uso terapêutico , Doenças Autoimunes/diagnóstico , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Clozapina/uso terapêutico , Teste de Tolerância a Glucose , Humanos , Masculino , Esquizofrenia Paranoide/tratamento farmacológico
12.
Metabolism ; 50(10): 1197-202, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11586493

RESUMO

South Asians who immigrate to the United States have a propensity toward insulin resistance, central obesity, and elevated total cholesterol:high-density lipoprotein (HDL) ratio. To evaluate whether these alterations are apparent at a younger age, we studied 32 offspring of South Asian immigrants and compared them with 29 of European descent between 18 to 30 years of age. American-born South Asian males had significantly higher total cholesterol, low-density lipoprotein (TC:LDL) ratios, triglycerides, and fasting insulin levels (13.9 +/- 7.1 and 10.0 +/- 5.5 microU/mL, P <.01) than their European counterparts. The South Asian females only had increased plasma insulin levels (15.3 +/- 8.8 and 10.0 +/- 5.1 microU/mL, P =.05). The entire South Asian group had higher truncal skinfold thickness (40.1 +/- 18.1 and 30.3 +/- 12.6 mm, P = <.05) and lower insulin-like growth factor binding protein (IGFBP)-1 levels (46.8 +/- 33.4 and 56.0 +/- 33.4 microg/L, P =.05). Plasma leptin levels were also significantly higher in both males (4.3 +/- 2.5 v 2.8 +/- 1.3 ng/mL, P =.0001) and females (20.5 +/- 10.3 v 10.3 +/- 6.3 ng/mL, P =.002) South Asian subjects. A significant correlation between plasma leptin and insulin, triglycerides, TC, and body mass index (BMI) was seen in the South Asian males. South Asians born in the United States show evidence for an altered metabolic profile in young adulthood. The relative contributions of inheritance and nutritional practices early in life to this alteration remain unclear.


Assuntos
Antropometria , Criança , Insulina/sangue , Leptina/sangue , Lipídeos/sangue , Adolescente , Adulto , Análise de Variância , Ásia/etnologia , Índice de Massa Corporal , Densitometria , Diabetes Mellitus/genética , Feminino , Humanos , Masculino , Fatores Sexuais , Dobras Cutâneas , Estados Unidos
13.
Am J Physiol Endocrinol Metab ; 281(5): E991-7, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11595655

RESUMO

The rate of glucose turnover (R(a)) and gluconeogenesis (GNG) via pyruvate were quantified in seven full-term healthy babies between 24 and 48 h after birth and in twelve low-birth-weight infants on days 3 and 4 by use of [(13)C(6)]glucose and (2)H(2)O. The preterm babies were receiving parenteral alimentation of either glucose or glucose plus amino acid with or without lipids. The contribution of GNG to glucose production was measured by the appearance of (2)H on C-6 of glucose. Glucose R(a) in full-term babies was 30 +/- 1.7 (SD) micromol. kg(-1). min(-1). GNG via pyruvate contributed approximately 31% to glucose R(a). In preterm babies, the contribution of GNG to endogenous glucose R(a) was variable (range 6-60%). The highest contribution was in infants receiving low rates of exogenous glucose infusion. In an additional group of infants of normal and diabetic mothers, lactate turnover and its incorporation into glucose were measured within 4-24 h of birth by use of [(13)C(3)]lactate tracer. The rate of lactate turnover was 38 micromol. kg(-1). min(-1), and lactate C, not corrected for loss of tracer in the tricarboxylic acid cycle, contributed approximately 18% to glucose C. Lactate and glucose kinetics were similar in infants that were small for their gestational age and in normal infants or infants of diabetic mothers. These data show that gluconeogenesis is evident soon after birth in the newborn infant and that, even after a brief fast (5 h), GNG via pyruvate makes a significant contribution to glucose production in healthy full-term infants. These data may have important implications for the nutritional support of the healthy and sick newborn infant.


Assuntos
Gluconeogênese , Aminoácidos/administração & dosagem , Glicemia/metabolismo , Água Corporal/metabolismo , Isótopos de Carbono , Deutério , Diabetes Mellitus Tipo 1/sangue , Feminino , Glucose/administração & dosagem , Glucose/metabolismo , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Recém-Nascido Pequeno para a Idade Gestacional , Ácido Láctico/sangue , Nutrição Parenteral , Gravidez , Gravidez em Diabéticas/sangue , Ácido Pirúvico/metabolismo
14.
J Perinatol ; 21(5): 320-3, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11536026

RESUMO

A large number of studies in recent years have described protein and nitrogen metabolism in the neonate. However, the majority of these data are difficult to interpret because of a number of confounding variables, particularly in very low birth weight (VLBW) infants. In contrast, application of state-of-the-art tracer isotopic and molecular biology methods in isolated cell system and whole animals has resulted in major advances in our understanding of the regulation of protein breakdown, synthesis, and protein accretion. The following workshop summary reviews the recent developments in basic physiology of protein metabolism in cellular and animal models in relation to human preterm infants, and identifies the important areas toward which future basic and clinical research should be directed to provide for optimal nitrogen accretion and growth of the VLBW infant.


Assuntos
Aminoácidos/metabolismo , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido de muito Baixo Peso/metabolismo , Proteínas/metabolismo , Feminino , Humanos , Recém-Nascido , Masculino , Nitrogênio/metabolismo , Necessidades Nutricionais
15.
Diabetes Care ; 24(9): 1602-7, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11522706

RESUMO

OBJECTIVE: We examined whether selected indexes of insulin sensitivity derived from an oral glucose tolerance test (IS(OGTT)) or fasting glucose/insulin levels (IS(QUICKI) and IS(HOMA)) can be used to predict insulin sensitivity in women before and during pregnancy. RESEARCH DESIGN AND METHODS: A 2-h euglycemic-hyperinsulinemic clamp (5 mmol/l glucose, 40 mU. m(-2). min(-1) insulin) and a 120-min oral glucose tolerance test (75 g load pregravid, 100 g pregnant) were repeated on 15 women (10 with normal glucose tolerance [NGT] and 5 with gestational diabetes mellitus [GDM]) pregravid and during both early (12-14 weeks) and late (34-36 weeks) pregnancy. An index of insulin sensitivity derived from the clamp (IS(CLAMP)) was obtained from glucose infusion rates adjusted for change in fat-free mass and endogenous glucose production measured using [6,6(-2)H(2)]glucose. RESULTS: Univariate analysis using combined groups and periods of pregnancy resulted in significant correlations between IS(CLAMP) and IS(OGTT) (r(2) = 0.74, P < 0.0001), IS(QUICKI) (r(2) = 0.64, P < 0.0001), and IS(HOMA) (r(2) = 0.53, P < 0.0001). The IS(OGTT) provided a significantly better correlation (P < 0.0001) than either IS(QUICKI) or IS(HOMA.) Multivariate analysis showed a significant group effect (P < 0.0003) on the prediction model, and separate equations were developed for the NGT (r(2) = 0.64, P < 0.0001) and GDM (r(2) = 0.85, P < 0.0001) groups. When subdivided by period of pregnancy, the correlation between IS(CLAMP) and IS(OGTT) pregravid was r(2) = 0.63 (P = 0.0002), during early pregnancy was r(2) = 0.80 (P < 0.0001), and during late pregnancy was r(2) = 0.64 (P = 0.0002). CONCLUSIONS: Estimates of insulin sensitivity from the IS(OGTT) during pregnancy were significantly better than from fasting glucose and insulin values. However, separate prediction equations are necessary for pregnant women with NGT and women with GDM.


Assuntos
Glicemia/metabolismo , Diabetes Gestacional/sangue , Teste de Tolerância a Glucose , Insulina/sangue , Gravidez/sangue , Análise de Variância , Composição Corporal , Jejum , Feminino , Humanos , Hiperinsulinismo , Infusões Intravenosas , Insulina/administração & dosagem , Insulina/farmacologia , Gravidez/fisiologia , Primeiro Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Valores de Referência , Análise de Regressão , Reprodutibilidade dos Testes
16.
J Appl Physiol (1985) ; 91(1): 357-62, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11408452

RESUMO

There is a controversy in the literature as to the effects of gender on leucine kinetics. Two research groups found that men oxidize more leucine during exercise, whereas another group showed no gender effects. The purpose of our study was to examine the effects of gender on leucine and, for comparison purposes, lysine kinetics. Our subjects (n = 14) were seven matched pairs of men and women selected for their exercise habits and age. After 1 wk of a standardized diet, they exercised at 50% of maximal O(2) uptake for 1 h. There was an effect of exercise in both genders: an increased leucine oxidation and an attenuation in nonoxidative leucine disposal compared with rest (P < 0.05). Furthermore, our study confirms that there are gender differences in leucine, but not lysine, kinetics. Men had a higher rate of leucine oxidation and a lower rate of nonoxidative leucine disposal during exercise (P < 0.05). For women, a larger proportion of their exercise energy needs came from fat; for men, a greater fraction came from carbohydrate (P < 0.05). We conclude that female exercisers rely to a greater extent on fat as an energy source, thereby using less carbohydrate, amino acid, and protein as a fuel source.


Assuntos
Leucina/metabolismo , Lisina/metabolismo , Caracteres Sexuais , Adulto , Sangue/metabolismo , Calorimetria Indireta , Metabolismo dos Carboidratos , Metabolismo Energético , Exercício Físico/fisiologia , Gorduras/metabolismo , Feminino , Homeostase , Humanos , Cinética , Masculino , Oxirredução , Urina/química
17.
J Biol Chem ; 276(16): 12928-31, 2001 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-11278297

RESUMO

Glyceroneogenesis, i.e. the synthesis of the glycerol moiety of triacylglycerol from pyruvate, has been suggested to be quantitatively important in both the liver and adipose tissue during fasting. However, the actual contribution of glyceroneogenesis to triacylglycerol synthesis has not been quantified in vivo in human studies. In the present study we have measured the contribution of glycerol and pyruvate to in vivo synthesis of hepatic triacylglycerol in nonpregnant and pregnant women after an overnight fast. Five nonpregnant women were administered [(13)C(3)]glycerol tracer as prime constant rate infusion, and the appearance of tracer in plasma glucose and triacylglycerol was quantified using gas chromatography-mass spectrometry. The contribution of pyruvate to hepatic triacylglycerol was quantified in nonpregnant and pregnant women using the deuterium labeling of body water method. The appearance of [(2)H] in hydrogens on C(1) and C(3) of triacylglycerol was measured following periodate oxidation of the glycerol isolated from hydrolyzed triacylglycerol. After a 16-h fast, approximately 6.1% of the plasma triacylglycerol pool was derived from plasma glycerol, whereas 10 to 60% was derived from pyruvate in nonpregnant women and pregnant women early in gestation. Our data suggest that glyceroneogenesis from pyruvate is quantitatively a major contributor to plasma triacylglycerol synthesis and may be important for the regulation of very low density lipoprotein triacylglycerol production. Our data also suggest that 3-glycerol phosphate is in rapid equilibrium with the triosephosphate pool, resulting in rapid labeling of the triose pool by the administered tracer glycerol. Because the rate of flux of triosephosphate to glucose during fasting far exceeds that to triacylglycerol, more glycerol ends up in glucose than in triacylglycerol. Alternatively, there may be two distinct pools of 3-glycerol phosphate in the liver, one involved in generating triosephosphate from glycerol and the other involved in glyceride-glycerol synthesis.


Assuntos
Glicerol/metabolismo , Fígado/metabolismo , Triglicerídeos/metabolismo , Glicemia/metabolismo , Isótopos de Carbono , Óxido de Deutério/farmacocinética , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Glucose/biossíntese , Glicerol/sangue , Humanos , Gravidez , Primeiro Trimestre da Gravidez , Piruvatos/metabolismo , Triglicerídeos/biossíntese
18.
Med Sci Sports Exerc ; 33(2): 237-41, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11224812

RESUMO

PURPOSE: The purpose of this study was to assess the relationship between whole-body leucine oxidation and oxygen consumption during steady-state exercise. Our hypothesis was that leucine oxidation will be responsive to increased whole-body energy needs. METHODS: Sixteen healthy individuals (7 women and 9 men) were infused with a stable isotope of leucine and, for comparison purposes, lysine during 60 min of moderate-intensity exercise. RESULTS: Leucine oxidation was increased (P < 0.05) and nonoxidative leucine disposal was decreased (P < 0.05), whereas leucine and lysine rate of appearance remained unchanged (P = NS) during exercise. Linear regression analysis indicated a modest relationship between leucine oxidation and steady-state oxygen consumption (R = 0.69; P < 0.003) during steady-state exercise. The coefficient of determination (R(2) = 0.49) indicates that approximately half of the variance in whole-body leucine oxidation during exercise can be explained by whole-body oxygen consumption. CONCLUSION: In a statistically appropriate sample size of humans whose dietary intake was controlled, the whole-body rate of leucine oxidation during exercise was only partially influenced by energy demands.


Assuntos
Exercício Físico/fisiologia , Leucina/metabolismo , Consumo de Oxigênio , Adulto , Dieta , Metabolismo Energético , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxirredução
19.
Am J Perinatol ; 17(1): 11-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10928598

RESUMO

The definition of hypoglycemia in the newborn infant has remained controversial because of lack of significant correlation between plasma glucose concentration, clinical symptoms, and long-term sequelae. A threshold value for plasma glucose at which clinical intervention should be considered is important because of the potential for serious neurological injury. In this review, we have described threshold values for plasma glucose in the newborn infant, based upon available data, at which the clinician should consider close monitoring and therapeutic interventions aimed at increasing the glucose level. In clinically symptomatic infants, plasma glucose concentrations of 45 mg/dL (2.5 mmol/L) or less should be considered as threshold for intervention. In an asymptomatic baby and in those at risk for hypoglycemia, irrespective of gestational and postnatal age, plasma glucose values less than 36 mg/dL (2.0 mmol/L) should be considered as threshold levels. Variances from these criteria, as in breast-fed infants, are discussed. The threshold values described for surveillance and intervention should be separated from the targeted therapeutic values which should be in the range of 72-90 mg/dL (4-5 mmol/L).


Assuntos
Glicemia/análise , Hipoglicemia/diagnóstico , Recém-Nascido/fisiologia , Fatores Etários , Aleitamento Materno , Gluconeogênese/fisiologia , Humanos , Hipoglicemia/terapia , Recém-Nascido Prematuro/fisiologia , Recém-Nascido Pequeno para a Idade Gestacional/fisiologia
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