RESUMO
The enantioselective carbenoid insertion into C(sp(3))-H bonds is an important tool for the synthesis of complex molecules due to the high control of enantioselectivity in the formation of stereogenic centers. This paper presents a brief review of the early issues, related mechanistic studies and recent applications on this chemistry area.
Assuntos
Ritmo Circadiano , Diabetes Mellitus Tipo 1/sangue , Hipoglicemia/etiologia , Criança , Diabetes Mellitus Tipo 1/tratamento farmacológico , Comportamento Alimentar , Hemoglobinas Glicadas/análise , Humanos , Hiperinsulinismo/etiologia , Hiperinsulinismo/prevenção & controle , Hipoglicemia/dietoterapia , Hipoglicemia/prevenção & controle , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Insulina/administração & dosagem , Insulina/uso terapêutico , Insulina Isófana/administração & dosagem , Insulina Isófana/uso terapêuticoRESUMO
To determine the prevalence and predictors of, and the glucose responses after, nocturnal hypoglycemia, we studied 135 pediatric patients with insulin-dependent diabetes mellitus on 388 nights. The frequencies of blood glucose values less than 60, 50, and 40 mg/dl (3.3, 2.8, and 2.2 mmol/L) at 2 AM were 14.4%, 7.0%, and 2.1%, and at 6 AM were 6.7%, 2.6%, and 0.5%, respectively. Longer duration of diabetes, higher daily insulin doses, and lower glycosylated hemoglobin values were all significant but weak predictors of 2 AM hypoglycemia (glucose less than or equal to 60 mg/dl (less than or equal to 3.3 mmol/L). A 10 PM glucose concentration less than or equal to 100 mg/dl (less than or equal to 5.6 mmol/L) was present on 48% of nights with 2 AM glucose values less than or equal to 60 mg/dl (less than or equal to 3.3 mmol/L), but only 24% of nights with 10 PM blood glucose values less than or equal to 100 mg/dl (less than or equal to 5.6 mmol/L) were followed by 2 AM hypoglycemia. After treatment of 70 episodes of 2 AM glucose concentrations less than or equal to 60 mg/dl (less than or equal to 3.3 mmol/L), mean 6 AM glucose concentration was 95 +/- 6 mg/dl (5.7 +/- 0.3 mmol/L) and less than or equal to 100 mg/dl in 68.6%. In only 4.3% of these cases was the 6 AM glucose concentration greater than 200 mg/dl (greater than 11.1 mmol/L). Among patients who experienced 2 AM hypoglycemia, after-breakfast glucose values were not greater on days with 2 AM hypoglycemia than on days without it. These data indicate that 2 AM hypoglycemia is relatively common in patients with insulin-dependent diabetes mellitus, is frequently preceded by a 10 PM glucose value less than or equal to 5.6 mmol/L, and is less well predicted by other factors. Appropriate treatment of 2 AM hypoglycemia seldom results in either before-breakfast or after-breakfast blood glucose values greater than 200 mg/dl (greater than 11.1 mmol/L). Early-morning hypoglycemia is an uncommon cause of otherwise unexplained, prebreakfast hyperglycemia in children with insulin-dependent diabetes mellitus.
Assuntos
Ritmo Circadiano , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemia/epidemiologia , Adolescente , Glicemia/análise , Escuridão , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/dietoterapia , Ingestão de Alimentos , Ingestão de Energia , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemia/sangue , Hipoglicemia/fisiopatologia , Insulina/administração & dosagem , Insulina/uso terapêutico , Prevalência , Probabilidade , Sensibilidade e Especificidade , Fatores de TempoRESUMO
To investigate the effect of site and timing of insulin injection on post-breakfast plasma glucose concentration, 23 children with type 1 diabetes were given their usual mixture of short- and intermediate-acting insulin five minutes prior to breakfast on one day and between 15 and 60 minutes before breakfast on the alternate day, depending on their 7:00 AM fasting blood glucose concentration. Thirteen children received insulin in an extremity, and 10 in the abdominal wall. Plasma insulin and glucose patterns were similar for the two injection sites. The mean post-breakfast peak glucose increment was significantly lower and the mean increment in free insulin values during the first hour after breakfast was higher on the day when insulin preceded breakfast by 30 to 60 minutes. Thus, significant reductions in post-breakfast hyperglycemia can be achieved by increasing the interval between the injection and breakfast in proportion to the fasting capillary glucose concentration. The timing of the morning insulin injection may be more important than the injection site.
Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Insulina/administração & dosagem , Adolescente , Glicemia/análise , Doença Crônica , Diabetes Mellitus Tipo 1/sangue , Jejum , Feminino , Humanos , Injeções Intravenosas , Injeções Subcutâneas , Insulina/sangue , Insulina de Ação Prolongada/administração & dosagem , Insulina Regular de Porco , Masculino , Fatores de TempoRESUMO
Two adolescents with insulin-dependent diabetes mellitus developed unusually severe diabetic neuropathy which responded to intensive measures to achieve improved metabolic control. Employing home blood glucose monitoring and either frequent insulin injections or a portable insulin infusion pump, painful peripheral neuropathy and autonomic gastrointestinal neuropathy improved after five and 12 months of therapy, respectively. During this period of time, abnormal ocular fluorophotometry, an early change in the eye of diabetic patients, also returned to normal. These patients demonstrate the reversibility of unusually severe neuropathy and early ocular changes in adolescents with diabetes when treated with intensive measures designed to improve metabolic control.
Assuntos
Complicações do Diabetes , Neuropatias Diabéticas/complicações , Gastroenteropatias/complicações , Tecido Nervoso/fisiopatologia , Adolescente , Adulto , Peso Corporal , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/metabolismo , Neuropatias Diabéticas/metabolismo , Neuropatias Diabéticas/terapia , Olho/metabolismo , Olho/patologia , Feminino , Fluoresceínas/metabolismo , Gastroenteropatias/metabolismo , Gastroenteropatias/terapia , Teste de Tolerância a Glucose , Hemoglobina A/análise , Humanos , Injeções Subcutâneas , Insulina/administração & dosagem , Insulina/uso terapêutico , Masculino , Monitorização Fisiológica , Tecido Nervoso/metabolismoRESUMO
A newly developed artificial pancreatic beta cell is described and its use in five children with diabetes mellitus is evaluated. This device can be programmed to bring the blood glucose concentration rapidly to a preselected level and normalize glucose tolerance in juvenile diabetic patients with markedly different insulin requirements. It is portable, can be operated by one person, and has been used to regulate the blood glucose concentration before, during, and after surgery requiring general anesthesia. The potential value of the device as an investigational tool is shown by demonstrating that regulation of the blood glucose concentration with insulin for seven to 24 hours does not alter circulating glucagon concentrations in the juvenile diabetic patients studied.