Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
1.
Nature ; 510(7506): 533-6, 2014 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-24776804

RESUMO

The transfer of somatic cell nuclei into oocytes can give rise to pluripotent stem cells that are consistently equivalent to embryonic stem cells, holding promise for autologous cell replacement therapy. Although methods to induce pluripotent stem cells from somatic cells by transcription factors are widely used in basic research, numerous differences between induced pluripotent stem cells and embryonic stem cells have been reported, potentially affecting their clinical use. Because of the therapeutic potential of diploid embryonic stem-cell lines derived from adult cells of diseased human subjects, we have systematically investigated the parameters affecting efficiency of blastocyst development and stem-cell derivation. Here we show that improvements to the oocyte activation protocol, including the use of both kinase and translation inhibitors, and cell culture in the presence of histone deacetylase inhibitors, promote development to the blastocyst stage. Developmental efficiency varied between oocyte donors, and was inversely related to the number of days of hormonal stimulation required for oocyte maturation, whereas the daily dose of gonadotropin or the total number of metaphase II oocytes retrieved did not affect developmental outcome. Because the use of concentrated Sendai virus for cell fusion induced an increase in intracellular calcium concentration, causing premature oocyte activation, we used diluted Sendai virus in calcium-free medium. Using this modified nuclear transfer protocol, we derived diploid pluripotent stem-cell lines from somatic cells of a newborn and, for the first time, an adult, a female with type 1 diabetes.


Assuntos
Núcleo Celular/genética , Reprogramação Celular , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patologia , Diploide , Oócitos/citologia , Células-Tronco Pluripotentes/citologia , Adulto , Blastocisto/efeitos dos fármacos , Fusão Celular , Cromossomos de Mamíferos/metabolismo , Feminino , Inibidores de Histona Desacetilases/farmacologia , Humanos , Recém-Nascido , Metáfase , Oócitos/metabolismo , Oogênese , Células-Tronco Pluripotentes/metabolismo , Células-Tronco Pluripotentes/patologia , Vírus Sendai , Fuso Acromático/metabolismo
2.
Am J Hum Genet ; 98(5): 934-955, 2016 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-27153397

RESUMO

Haplotype-dependent allele-specific methylation (hap-ASM) can impact disease susceptibility, but maps of this phenomenon using stringent criteria in disease-relevant tissues remain sparse. Here we apply array-based and Methyl-Seq approaches to multiple human tissues and cell types, including brain, purified neurons and glia, T lymphocytes, and placenta, and identify 795 hap-ASM differentially methylated regions (DMRs) and 3,082 strong methylation quantitative trait loci (mQTLs), most not previously reported. More than half of these DMRs have cell type-restricted ASM, and among them are 188 hap-ASM DMRs and 933 mQTLs located near GWAS signals for immune and neurological disorders. Targeted bis-seq confirmed hap-ASM in 12/13 loci tested, including CCDC155, CD69, FRMD1, IRF1, KBTBD11, and S100A(∗)-ILF2, associated with immune phenotypes, MYT1L, PTPRN2, CMTM8 and CELF2, associated with neurological disorders, NGFR and HLA-DRB6, associated with both immunological and brain disorders, and ZFP57, a trans-acting regulator of genomic imprinting. Polymorphic CTCF and transcription factor (TF) binding sites were over-represented among hap-ASM DMRs and mQTLs, and analysis of the human data, supplemented by cross-species comparisons to macaques, indicated that CTCF and TF binding likelihood predicts the strength and direction of the allelic methylation asymmetry. These results show that hap-ASM is highly tissue specific; an important trans-acting regulator of genomic imprinting is regulated by this phenomenon; and variation in CTCF and TF binding sites is an underlying mechanism, and maps of hap-ASM and mQTLs reveal regulatory sequences underlying supra- and sub-threshold GWAS peaks in immunological and neurological disorders.


Assuntos
Metilação de DNA , Impressão Genômica , Haplótipos/genética , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas , Transativadores/genética , Alelos , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Feminino , Estudo de Associação Genômica Ampla , Humanos , Doenças do Sistema Imunitário/genética , Macaca mulatta , Macaca radiata , Doenças do Sistema Nervoso/genética , Placenta/metabolismo , Placenta/patologia , Gravidez , Especificidade da Espécie , Linfócitos T/metabolismo , Linfócitos T/patologia
3.
Nature ; 493(7434): 632-7, 2013 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-23254936

RESUMO

Mitochondrial DNA mutations transmitted maternally within the oocyte cytoplasm often cause life-threatening disorders. Here we explore the use of nuclear genome transfer between unfertilized oocytes of two donors to prevent the transmission of mitochondrial mutations. Nuclear genome transfer did not reduce developmental efficiency to the blastocyst stage, and genome integrity was maintained provided that spontaneous oocyte activation was avoided through the transfer of incompletely assembled spindle-chromosome complexes. Mitochondrial DNA transferred with the nuclear genome was initially detected at levels below 1%, decreasing in blastocysts and stem-cell lines to undetectable levels, and remained undetectable after passaging for more than one year, clonal expansion, differentiation into neurons, cardiomyocytes or ß-cells, and after cellular reprogramming. Stem cells and differentiated cells had mitochondrial respiratory chain enzyme activities and oxygen consumption rates indistinguishable from controls. These results demonstrate the potential of nuclear genome transfer to prevent the transmission of mitochondrial disorders in humans.


Assuntos
DNA Mitocondrial/genética , Técnicas de Transferência Nuclear/normas , Oócitos , Linhagem Celular , Células Cultivadas , Criopreservação , Desenvolvimento Embrionário , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Genótipo , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Oócitos/citologia , Oócitos/metabolismo
4.
Diabetes Care ; 46(5): 1005-1013, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36920087

RESUMO

OBJECTIVE: Previous studies showed that inhibiting lymphocyte costimulation reduces declining ß-cell function in individuals newly diagnosed with type 1 diabetes. We tested whether abatacept would delay or prevent progression of type 1 diabetes from normal glucose tolerance (NGT) to abnormal glucose tolerance (AGT) or to diabetes and the effects of treatment on immune and metabolic responses. RESEARCH DESIGN AND METHODS: We conducted a phase 2, randomized, placebo-controlled, double-masked trial of abatacept in antibody-positive participants with NGT who received monthly abatacept/placebo infusions for 12 months. The end point was AGT or diabetes, assessed by oral glucose tolerance tests. RESULTS: A total of 101 participants received abatacept and 111 placebo. Of these, 81 (35 abatacept and 46 placebo) met the end point of AGT or type 1 diabetes diagnosis (hazard ratio 0.702; 95% CI 0.452, 1.09; P = 0.11) The C-peptide responses to oral glucose tolerance tests were higher in the abatacept arm (P < 0.03). Abatacept reduced the frequency of inducible T-cell costimulatory (ICOS)+ PD1+ T-follicular helper (Tfh) cells during treatment (P < 0.0001), increased naive CD4+ T cells, and also reduced the frequency of CD4+ regulatory T cells (Tregs) from the baseline (P = 0.0067). Twelve months after treatment, the frequency of ICOS+ Tfh, naive CD4+ T cells, and Tregs returned to baseline. CONCLUSIONS: Although abatacept treatment for 1 year did not significantly delay progression to glucose intolerance in at-risk individuals, it impacted immune cell subsets and preserved insulin secretion, suggesting that costimulation blockade may modify progression of type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1 , Humanos , Abatacepte/uso terapêutico , Abatacepte/farmacologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Imunossupressores , Linfócitos T Reguladores , Glucose/uso terapêutico
5.
Commun Biol ; 5(1): 779, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35918471

RESUMO

Mutations in HNF1A cause Maturity Onset Diabetes of the Young (HNF1A-MODY). To understand mechanisms of ß-cell dysfunction, we generated stem cell-derived pancreatic endocrine cells with hypomorphic mutations in HNF1A. HNF1A-deficient ß-cells display impaired basal and glucose stimulated-insulin secretion, reduced intracellular calcium levels in association with a reduction in CACNA1A expression, and accumulation of abnormal insulin granules in association with SYT13 down-regulation. Knockout of CACNA1A and SYT13 reproduce the relevant phenotypes. In HNF1A deficient ß-cells, glibenclamide, a sulfonylurea drug used in the treatment of HNF1A-MODY patients, increases intracellular calcium, and restores insulin secretion. While insulin secretion defects are constitutive in ß-cells null for HNF1A, ß-cells heterozygous for hypomorphic HNF1A (R200Q) mutations lose the ability to secrete insulin gradually; this phenotype is prevented by correction of the mutation. Our studies illuminate the molecular basis for the efficacy of treatment of HNF1A-MODY with sulfonylureas, and suggest promise for the use of cell therapies.


Assuntos
Diabetes Mellitus Tipo 2 , Insulina , Cálcio/metabolismo , Diabetes Mellitus Tipo 2/genética , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 1-alfa Nuclear de Hepatócito/metabolismo , Humanos , Insulina/metabolismo , Insulina Regular Humana , Células-Tronco/metabolismo , Sinaptotagminas
6.
JCI Insight ; 6(5)2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33529174

RESUMO

Limitations in cell proliferation are important for normal function of differentiated tissues and essential for the safety of cell replacement products made from pluripotent stem cells, which have unlimited proliferative potential. To evaluate whether these limitations can be established pharmacologically, we exposed pancreatic progenitors differentiating from human pluripotent stem cells to small molecules that interfere with cell cycle progression either by inducing G1 arrest or by impairing S phase entry or S phase completion and determined growth potential, differentiation, and function of insulin-producing endocrine cells. We found that the combination of G1 arrest with a compromised ability to complete DNA replication promoted the differentiation of pancreatic progenitor cells toward insulin-producing cells and could substitute for endocrine differentiation factors. Reduced replication fork speed during differentiation improved the stability of insulin expression, and the resulting cells protected mice from diabetes without the formation of cystic growths. The proliferative potential of grafts was proportional to the reduction of replication fork speed during pancreatic differentiation. Therefore, a compromised ability to enter and complete S phase is a functionally important property of pancreatic endocrine differentiation, can be achieved by reducing replication fork speed, and is an important determinant of cell-intrinsic limitations of growth.


Assuntos
Ciclo Celular , Diferenciação Celular , Replicação do DNA , Diabetes Mellitus , Células-Tronco Pluripotentes Induzidas , Células Secretoras de Insulina , Transplante de Células-Tronco , Animais , Afidicolina , Proliferação de Células , Diabetes Mellitus/terapia , Humanos , Insulina/metabolismo , Ilhotas Pancreáticas , Camundongos , Pâncreas , Células-Tronco Pluripotentes , Transplantes
7.
Diabetes Care ; 43(8): 1836-1842, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32457058

RESUMO

OBJECTIVE: Insulin secretion declines rapidly after diagnosis of type 1 diabetes, followed by a slower rate of change. Previous studies have demonstrated that the C-peptide decline begins before the clinical diagnosis. Changes in insulin secretion in the same individuals studied from preclinical stages through and after clinical diagnosis have not been previously reported. RESEARCH DESIGN AND METHODS: Antibody-positive relatives undergo sequential oral glucose tolerance testing (OGTT) as part of TrialNet's Pathway to Prevention study and continue both OGTT and mixed-meal tolerance testing (MMTT) as part of the Long-term Investigational Follow-up in TrialNet study if they develop type 1 diabetes. We analyzed glucose and C-peptide data obtained from 80 TrialNet subjects who had OGTT before and after clinical diagnosis. Separately, we compared C-peptide response to OGTT and MMTT in 127 participants after diagnosis. RESULTS: C-peptide did not change significantly until 6 months before the clinical diagnosis of type 1 diabetes and continued to decline postdiagnosis, and the rates of decline for the first 6 months postdiagnosis were similar to the 6 months prediagnosis. There were no significant differences in MMTT and OGTT C-peptide responses in paired tests postdiagnosis. CONCLUSIONS: This is the first analysis of C-peptide levels in longitudinally monitored patients with type 1 diabetes studied from before diagnosis and continuing to the postdiagnosis period. These data highlight the discordant timing between accelerated ß-cell dysfunction and the current glucose thresholds for clinical diagnosis. To preserve ß-cell function, disease-modifying therapy should start at or before the acute decline in C-peptide.


Assuntos
Peptídeo C/sangue , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/diagnóstico , Adolescente , Adulto , Glicemia/metabolismo , Peptídeo C/análise , Criança , Pré-Escolar , Estudos de Coortes , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/patologia , Técnicas de Diagnóstico Endócrino , Progressão da Doença , Feminino , Seguimentos , Teste de Tolerância a Glucose , Humanos , Secreção de Insulina/fisiologia , Estudos Longitudinais , Masculino , Refeições , Pessoa de Meia-Idade , Monitorização Fisiológica , Adulto Jovem
8.
Diabetes Technol Ther ; 20(8): 517-523, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29990438

RESUMO

BACKGROUND: Gestational tight glycemic control is critical for women with type 1 diabetes (T1D). Limited data exist on the adoption and retention of diabetes technologies among women in different parity strata. METHODS: We compared T1D management between T1D Exchange clinic registry participants (mean age 28 ± 9 years, 84% white non-Hispanic, and median T1D duration 13 years) who were pregnant at enrollment or year 1 follow-up ("recently pregnant" between 2010 and 2013, n = 214), ever (but not recently) pregnant (n = 1540), and never pregnant (n = 2586). We examined self-reported maternal and fetal outcomes in 130 women who delivered a baby within the last year. RESULTS: Recently pregnant women had the lowest hemoglobin A1c (6.5% pregnant vs. 7.8% ever pregnant vs. 8.0% never pregnant, P < 0.001). Recently pregnant women reported the highest use of continuous subcutaneous insulin infusion (74% vs. 60% vs. 58%, adjusted P < 0.001) and continuous glucose monitor (CGM) (36% vs.17% vs. 12%, adjusted P < 0.001) therapies compared with ever or never pregnant women, respectively, after adjusting for age, diabetes duration, and socioeconomic status. Among women 18-25 years old, CGM use was highest among recently pregnant women (adjusted P = 0.0022). Never pregnant women 26-45 years old had a higher use of CGM compared with younger counterparts (adjusted P < 0.001). Adverse maternal and fetal outcomes were common. CONCLUSIONS: Despite high uptake levels of advanced diabetes technologies among pregnant women, rates of adverse maternal and fetal outcomes remain high. More studies are needed to determine how these technologies could be best used in pregnancy and postpartum to improve health outcomes among women with T1D.


Assuntos
Glicemia/análise , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Sistemas de Infusão de Insulina , Insulina/uso terapêutico , Gravidez em Diabéticas/tratamento farmacológico , Adolescente , Adulto , Diabetes Mellitus Tipo 1/sangue , Gerenciamento Clínico , Feminino , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Gravidez , Gravidez em Diabéticas/sangue , Sistema de Registros , Resultado do Tratamento , Adulto Jovem
9.
Pediatr Dent ; 29(5): 426-30, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18027779

RESUMO

PURPOSE: This study assessed gingival bleeding in diabetic children during the mixed dentition period. METHODS: Three hundred fifty-five 6- to 13-year-old diabetic (99% type 1) and nondiabetic control children in the mixed dentition stage were evaluated from a total cohort of 700 6- to 18-year-old children. Gingival status was assessed, and data on important diabetes-related variables were collected. Analyses were performed using Poisson's regression. RESULTS: Diabetic children had significantly more gingival bleeding than controls for both primary and permanent teeth. The risk of gingival bleeding around the primary teeth in cases was 35% more than in the control group (P=.001); and the risk of gingival bleeding around the permanent teeth in cases was 57% more than in the controls (P<.001). The number of teeth with bleeding had a very modest, but statistically significant, association with: (1) mean HbA1c; (2) body mass index (BMI)-for-age percentile; and (3) duration of diabetes. CONCLUSIONS: These findings demonstrate that diabetic children are at a significantly higher risk for gingival bleeding. Diabetes-related oral complications affect the primary periodontium as early as age 6 and possibly earlier. The emphasis on oral hygiene may be valuable in preventing future periodontal complications in diabetic patients.


Assuntos
Diabetes Mellitus Tipo 1/complicações , Hemorragia Gengival/etiologia , Adolescente , Índice de Massa Corporal , Estudos de Casos e Controles , Criança , Índice de Placa Dentária , Dentição Mista , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Higiene Bucal , Índice Periodontal , Análise de Regressão
10.
Mol Imaging Biol ; 18(2): 292-301, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26370678

RESUMO

PURPOSE: The vesicular monoamine transporter, type 2 (VMAT2) is expressed by insulin producing ß cells and was evaluated as a biomarker of ß cell mass (BCM) by positron emission tomography (PET) with [(18)F]fluoropropyl-dihydrotetrabenazine ([(18)F]FP-(+)-DTBZ). PROCEDURES: We evaluated the feasibility of longitudinal pancreatic PET VMAT2 quantification in the pancreas in two studies of healthy controls and patients with type 1 or 2 diabetes. VMAT2 binding potential (BPND) was estimated voxelwise using a reference tissue method in a cross-sectional study, followed by assessment of reproducibility using a test-retest paradigm. Metabolic function was evaluated by stimulated c-peptide measurements. RESULTS: Pancreatic BPND was significantly decreased in patients with type 1 diabetes relative to controls and the test-retest variability was 9.4%. CONCLUSIONS: Pancreatic VMAT2 content is significantly reduced in long-term diabetes patients relative to controls and repeat scans are sufficiently reproducible to suggest the feasibility clinically VMAT2 measurements in longitudinal studies of new onset diabetes.


Assuntos
Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Radioisótopos de Flúor/metabolismo , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Tomografia por Emissão de Pósitrons/métodos , Tetrabenazina/análogos & derivados , Adulto , Estudos de Casos e Controles , Tamanho Celular , Demografia , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/patologia , Feminino , Glucose/farmacologia , Humanos , Insulina/genética , Insulina/metabolismo , Células Secretoras de Insulina/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Ligação Proteica/efeitos dos fármacos , Tetrabenazina/metabolismo , Proteínas Vesiculares de Transporte de Monoamina/genética , Proteínas Vesiculares de Transporte de Monoamina/metabolismo
11.
Diabetes Care ; 39(1): 122-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26628417

RESUMO

OBJECTIVE: We evaluated pregnancy outcomes, maternal and fetal/neonatal, during the Treatment Options for type 2 Diabetes in Adolescents and Youth (TODAY) study. RESEARCH DESIGN AND METHODS: The TODAY study was a randomized controlled trial comparing three treatment options for youth with type 2 diabetes. Informed consent included the requirement for contraception, including abstinence; this was reinforced at each visit. Following informed consent, self-reported data related to the mother's prenatal care and delivery and the infant's health were retrospectively collected. When permitted, maternal medical records and infant birth records were reviewed. RESULTS: Of the 452 enrolled female participants, 46 (10.2%) had 63 pregnancies. Despite continued emphasis on adequate contraception, only 4.8% of the pregnant participants reported using contraception prior to pregnancy. The mean age at first pregnancy was 18.4 years; the mean diabetes duration was 3.17 years. Seven pregnancies were electively terminated; three pregnancies had no data reported. Of the remaining 53 pregnancies, 5 (9.4%) resulted in early pregnancy loss, and 7 (13%) resulted in loss with inadequate pregnancy duration data. Two pregnancies ended in stillbirth, at 27 and 37 weeks, and 39 ended with a live-born infant. Of the live-born infants, six (15.4%) were preterm and eight (20.5%) had a major congenital anomaly. CONCLUSIONS: Despite diabetes-specific information recommending birth control and the avoidance of pregnancy, 10% of the study participants became pregnant. Pregnancies in youth with type 2 diabetes may be especially prone to result in congenital anomalies. Reasons for the high rate of congenital anomalies are uncertain, but may include poor metabolic control and extreme obesity.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Resultado da Gravidez , Gravidez em Diabéticas/epidemiologia , Adolescente , Parto Obstétrico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Feminino , Humanos , Recém-Nascido , Cooperação do Paciente , Gravidez , Cuidado Pré-Natal , Natimorto
12.
Diabetes Care ; 39(4): 603-10, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26681721

RESUMO

OBJECTIVE: Severe hypoglycemia is common in older adults with long-standing type 1 diabetes, but little is known about factors associated with its occurrence. RESEARCH DESIGN AND METHODS: A case-control study was conducted at 18 diabetes centers in the T1D Exchange Clinic Network. Participants were ≥60 years old with type 1 diabetes for ≥20 years. Case subjects (n = 101) had at least one severe hypoglycemic event in the prior 12 months. Control subjects (n = 100), frequency-matched to case subjects by age, had no severe hypoglycemia in the prior 3 years. Data were analyzed for cognitive and functional abilities, social support, depression, hypoglycemia unawareness, various aspects of diabetes management, C-peptide level, glycated hemoglobin level, and blinded continuous glucose monitoring (CGM) metrics. RESULTS: Glycated hemoglobin (mean 7.8% vs. 7.7%) and CGM-measured mean glucose (175 vs. 175 mg/dL) were similar between case and control subjects. More case than control subjects had hypoglycemia unawareness: only 11% of case subjects compared with 43% of control subjects reported always having symptoms associated with low blood glucose levels (P < 0.001). Case subjects had greater glucose variability than control subjects (P = 0.008) and experienced CGM glucose levels <60 mg/dL for ≥20 min on 46% of days compared with 33% of days in control subjects (P = 0.10). On certain cognitive tests, case subjects scored worse than control subjects. CONCLUSIONS: In older adults with long-standing type 1 diabetes, greater hypoglycemia unawareness and glucose variability are associated with an increased risk of severe hypoglycemia. A study to assess interventions to prevent severe hypoglycemia in high-risk individuals is needed.


Assuntos
Diabetes Mellitus Tipo 1/sangue , Hipoglicemia/sangue , Idoso , Glicemia/metabolismo , Peptídeo C/sangue , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Hipoglicemia/complicações , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Fatores de Risco
13.
Diabetes Care ; 38(3): 476-81, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25519448

RESUMO

OBJECTIVE: It is generally accepted that complete ß-cell destruction eventually occurs in individuals with type 1 diabetes, which has implications for treatment approaches and insurance coverage. The frequency of residual insulin secretion in a large cohort of individuals at varying ages of diagnosis and type 1 diabetes duration is unknown. RESEARCH DESIGN AND METHODS: The frequency of residual insulin secretion was determined by measurement of nonfasting serum C-peptide concentration in 919 individuals with type 1 diabetes according to prespecified groups based on age at diagnosis and duration of disease (from 3 to 81 years' duration). Stimulated C-peptide was measured in those with detectable nonfasting values and a group of those with undetectable values as control. RESULTS: The overall frequency of detectable nonfasting C-peptide was 29%, decreasing with time from diagnosis regardless of age at diagnosis. In all duration groups, the frequency of C-peptide was higher with diagnosis age >18 years compared with ≤18 years. Nineteen percent of those with undetectable nonfasting C-peptide were C-peptide positive upon stimulation testing. CONCLUSIONS: The American Diabetes Association's definition of type 1 diabetes as "usually leading to absolute insulin deficiency" results in clinicians often considering the presence of residual insulin secretion as unexpected in this population. However, our data suggest that residual secretion is present in almost one out of three individuals 3 or more years from type 1 diabetes diagnosis. The frequency of residual C-peptide decreases with time from diagnosis regardless of age at diagnosis, yet at all durations of disease, diagnosis during adulthood is associated with greater frequency and higher values of C-peptide.


Assuntos
Peptídeo C/sangue , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Peptídeo C/metabolismo , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/diagnóstico , Feminino , Humanos , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
14.
Diabetes Care ; 36(11): 3573-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24026543

RESUMO

OBJECTIVE: Optimizing glycemic control in type 1 diabetes is important to minimize the risk of complications. We used the large T1D Exchange clinic registry database to identify characteristics and diabetes management techniques in adults with type 1 diabetes, differentiating those under excellent glycemic control from those with poorer control. RESEARCH DESIGN AND METHODS: The cross-sectional analysis included 627 participants with HbA1c <6.5% (excellent control) and 1,267 with HbA1c ≥8.5% (fair/poor control) at enrollment who were ≥26 years of age (mean ± SD 45.9 ± 13.2 years), were not using continuous glucose monitoring, and had type 1 diabetes for ≥2 years (22.8 ± 13.0 years). RESULTS: Compared with the fair/poor control group, participants in the excellent control group had higher socioeconomic status, were more likely to be older and married, were less likely to be overweight, were more likely to exercise frequently, and had lower total daily insulin dose per kilogram (P < 0.0001 for each). Excellent control was associated with more frequent self-monitoring of blood glucose (SMBG), giving mealtime boluses before a meal rather than at the time of or after a meal, performing SMBG before giving a bolus, and missing an insulin dose less frequently (P < 0.0001 for each). Frequency of severe hypoglycemia was similar between groups, whereas diabetic ketoacidosis was more common in the fair/poor control group. CONCLUSIONS: Diabetes self-management related to insulin delivery, glucose monitoring, and lifestyle tends to differ among adults with type 1 diabetes under excellent control compared with those under poorer control. Future studies should focus on modifying diabetes management skills in adult type 1 diabetes patients with suboptimal glycemic control.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Insulina/administração & dosagem , Qualidade da Assistência à Saúde , Autocuidado , Adulto , Glicemia/análise , Automonitorização da Glicemia , Estudos Transversais , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/complicações , Cetoacidose Diabética/epidemiologia , Feminino , Humanos , Hipoglicemia/epidemiologia , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Adulto Jovem
15.
Diabetes Care ; 36(7): 2009-14, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23378621

RESUMO

OBJECTIVE: Despite substantial evidence of the benefit of frequent self-monitoring of blood glucose (SMBG) in type 1 diabetes, certain insurers limit the number of test strips that they will provide. The large database of the T1D Exchange clinic registry provided an opportunity to evaluate the relationship between the number of SMBG measurements per day and HbA1c levels across a wide age range of children and adults. RESEARCH DESIGN AND METHODS: The analysis included 20,555 participants in the T1D Exchange clinic registry with type 1 diabetes ≥1 year and not using a continuous glucose monitor (11,641 younger than age 18 years and 8,914 18 years old or older). General linear models were used to assess the association between the number of SMBG measurements and HbA1c levels after adjusting for potential confounding variables. RESULTS: A higher number of SMBG measurements per day were associated with non-Hispanic white race, insurance coverage, higher household income, and use of an insulin pump for insulin delivery (P < 0.001 for each factor). After adjusting for these factors, a higher number of SMBG measurements per day was strongly associated with a lower HbA1c level (adjusted P < 0.001), with the association being present in all age-groups and in both insulin pump and injection users. CONCLUSIONS: There is a strong association between higher SMBG frequency and lower HbA1c levels. It is important for insurers to consider that reducing restrictions on the number of test strips provided per month may lead to improved glycemic control for some patients with type 1 diabetes.


Assuntos
Automonitorização da Glicemia/estatística & dados numéricos , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/sangue , Hemoglobinas Glicadas/metabolismo , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/metabolismo , Feminino , Humanos , Lactente , Sistemas de Infusão de Insulina , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Ann N Y Acad Sci ; 1243: 119-34, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22211897

RESUMO

The clinical care of patients with type 1 diabetes (T1D) has greatly improved over the past few decades; however, it remains impossible to completely normalize blood sugar utilizing currently available tools. Research is underway with a goal to improve the care and, ultimately, to cure T1D by preserving beta cells. This review will outline the progress that has been made in trials aimed at preserving insulin secretion in T1D by modifying the immune assault on the pancreatic beta cell. Although not yet ready for clinical use, successful trials have been conducted in new-onset T1D that demonstrated utility of three experimental agents with disparate modes of action (anti-T cell, anti-B cell, and costimulation blockade) to preserve insulin secretion. In contrast, prevention studies have so far failed to produce positive results but have shown that such studies are feasible and have identified new promising agents for study.


Assuntos
Diabetes Mellitus Tipo 1/terapia , Células Secretoras de Insulina/imunologia , Células Secretoras de Insulina/metabolismo , Abatacepte , Anticorpos Monoclonais Murinos/uso terapêutico , Ensaios Clínicos como Assunto , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/fisiopatologia , Diabetes Mellitus Tipo 1/prevenção & controle , Humanos , Imunoconjugados/uso terapêutico , Terapia de Imunossupressão , Modelos Imunológicos , Muromonab-CD3/uso terapêutico , Rituximab
18.
Pediatrics ; 121(5): e1139-43, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18450858

RESUMO

OBJECTIVE: The objective of this study was to evaluate tooth eruption in 6- to 14-year-old children with diabetes mellitus. METHODS: Tooth eruption status was assessed for 270 children with diabetes and 320 control children without diabetes. Data on important diabetes-related variables were collected. Analyses were performed using logistic regression models. RESULTS: Children with diabetes exhibited accelerated tooth eruption in the late mixed dentition period (10-14 years of age) compared to healthy children. For both case patients and control subjects the odds of a tooth being in an advanced eruptive stage were significantly higher among girls than boys. There was also a trend associating gingival inflammation with expedited tooth eruption in both groups. No association was found between the odds of a tooth being in an advanced stage of eruption and hemoglobin A(1c) or duration of diabetes. Patients with higher body mass index percentile demonstrated statistically higher odds for accelerated tooth eruption, but the association was not clinically significant. CONCLUSIONS: Children with diabetes exhibit accelerated tooth eruption. Future studies need to ascertain the role of such aberrations in dental development and complications such as malocclusion, impaired oral hygiene, and periodontal disease. The standards of care for children with diabetes should include screening and referral programs aimed at oral health promotion and disease prevention.


Assuntos
Diabetes Mellitus Tipo 1/fisiopatologia , Erupção Dentária , Adolescente , Índice de Massa Corporal , Criança , Índice de Placa Dentária , Diabetes Mellitus Tipo 1/complicações , Feminino , Gengivite/complicações , Hemoglobinas Glicadas/análise , Humanos , Masculino
19.
J Clin Periodontol ; 34(4): 294-8, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17378885

RESUMO

AIM: The association between diabetes mellitus and periodontal attachment and bone loss is well established. Most of the prior literature has focused on adults, and studies in children have mostly reported gingival changes. Our aim was to assess the periodontal status of a large cohort of children and adolescents with diabetes. MATERIAL AND METHODS: We examined 350 children with diabetes (cases) and 350 non-diabetic controls (6-18 years of age). Using three different case definitions for periodontal disease, which incorporated gingival bleeding and/or attachment loss findings, multiple logistic regression analyses adjusting for age, gender, ethnicity, frequency of prior dental visits, dental plaque, and examiner were performed. RESULTS: Subjects with diabetes had increased gingival inflammation and attachment loss compared with controls. Regression analyses revealed statistically significant differences in periodontal destruction between cases and controls across all disease definitions tested (odds ratios ranging from 1.84 to 3.72). The effect of diabetes on periodontal destruction remained significant when we separately analysed 6-11 and 12-18 year old subgroups. CONCLUSIONS: These findings demonstrate an association between diabetes and an increased risk for periodontal destruction even very early in life, and suggest that programmes to address periodontal needs should be the standard of care for diabetic youth.


Assuntos
Perda do Osso Alveolar/etiologia , Diabetes Mellitus Tipo 1/complicações , Perda da Inserção Periodontal/etiologia , Adolescente , Estudos de Casos e Controles , Criança , Feminino , Humanos , Modelos Logísticos , Masculino , Índice Periodontal
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA