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AIMS: Insulin pump failure and/or malfunction requiring replacement have not been thoroughly investigated. This study evaluated pump replacement in children and adolescents with Type 1 diabetes using insulin pump therapy. METHODS: Data were collected for all participants younger than 19 years, starting insulin pump therapy before 31 December 2013. For each child, age, disease duration, date of insulin pump therapy initiation, insulin pump model, failure/malfunction/replacement yes/no and reason were considered for the year 2013. RESULTS: Data were returned by 40 of 43 paediatric centres belonging to the Diabetes Study Group of the Italian Society of Paediatric Endocrinology and Diabetology. In total, 1574 of 11 311 (13.9%) children and adolescents with Type 1 diabetes were using an insulin pump: 29.2% Animas VIBE™ , 9.4% Medtronic MiniMed 715/515™ , 34.3% Medtronic MiniMed VEO™ , 24.3% Accu-Check Spirit Combo™ and 2.8% other models. In 2013, 0.165 insulin pump replacements per patient-year (11.8% due to pump failure/malfunction and 4.7% due to accidental damage) were recorded. Animas VIBE™ (22.1%) and Medtronic MiniMed VEO™ (17.7%) were the most replaced. CONCLUSIONS: In a large cohort of Italian children and adolescents with Type 1 diabetes, insulin pump failure/malfunction and consequent replacement are aligned with rates previously reported and higher in more sophisticated pump models.
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Diabetes Mellitus Tipo 1/tratamento farmacológico , Falha de Equipamento/estatística & dados numéricos , Sistemas de Infusão de Insulina , Insulina/administração & dosagem , Adolescente , Glicemia/análise , Glicemia/efeitos dos fármacos , Automonitorização da Glicemia/instrumentação , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/epidemiologia , Feminino , Humanos , Lactente , Itália/epidemiologia , Masculino , Estudos RetrospectivosRESUMO
BACKGROUND: Due to the failure of the "old Mason loop," the mini-gastric bypass (MGB) has been viewed with skepticism. During the past 12 years, a growing number of authors from around the world have continued to report excellent short- and long-term results with MGB. METHODS: One university center, three regional hospitals, and two private hospitals participated in this study. From July 2006 to December 2012, 475 men (48.8 %) and 499 women (51.2 %) underwent 974 laparoscopic MGBs. The mean age of these patients was 39.4, and their preoperative body mass index was 48 ± 4.58 kg/m(2). Type 2 diabetes mellitus (T2DM) affected 224 (22.9 %) of the 974 patients, whereas 291 of the 974 patients (29.8 %) presented with hypertension. The preoperative gastrointestinal status was explored in all the patients through esophagogastroduodenoscopia. The major end points of the study were definitions of both MGB safety and efficacy in the long term as well as the endoscopic changes in symptomatic patients eventually produced by surgery. RESULTS: The rate of conversion to open surgery was 1.2 % (12/974), and the mortality rate was 0.2 % (2/974). The perioperative morbidity rate was 5.5 % (54/974), with 20 (2 %) of the 974 patients requiring an early surgical revision. The mean hospital length of stay was 4.0 ± 1.7 days. At this writing, 818 patients are being followed up. Late complications have affected 74 (9 %) of the 818 patients. The majority of these complications (66/74, 89.1 %) have occurred within 1 year after surgery. Bile reflux gastritis was symptomatic, with endoscopic findings reported for 8 (0.9 %) and acid peptic ulcers for 14 (1.7 %) of the 818 patients. A late revision surgery was required for 7 (0.8 %) of the 818 patients. No patient required revision surgery due to biliary gastritis. At 60 months, the percentage of excess weight loss was 77 ± 5.1 %, the T2DM remission was 84.4 %, and the resolution of hypertension was 87.5 %. CONCLUSIONS: Despite initial skepticism, this study, together with many other large-scale, long-term similar studies from around the world (e.g., Taiwan, United States, France, Spain, India, Lebanon) demonstrated the MGB to be a short, simple, low-risk, effective, and durable bariatric procedure.
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Derivação Gástrica/métodos , Laparoscopia/métodos , Obesidade Mórbida/cirurgia , Adulto , Índice de Massa Corporal , Comorbidade , Conversão para Cirurgia Aberta , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Seguimentos , Derivação Gástrica/mortalidade , Humanos , Hipertensão/epidemiologia , Itália , Laparoscopia/mortalidade , Tempo de Internação , Masculino , Obesidade Mórbida/epidemiologia , Reoperação , Taxa de Sobrevida , Resultado do Tratamento , Estados Unidos , Redução de PesoRESUMO
Background: Rabson-Mendenhall syndrome (RMS), a rare disorder characterized by severe insulin resistance due to biallelic loss-of-function variants of the insulin receptor gene (INSR), presents therapeutic challenges (OMIM: 262190). This case study explores the efficacy of adjunctive therapy with sodium-glucose cotransporter 2 inhibitors (SGLT2is) in the management of RMS in an 11-year-old male patient with compound heterozygous pathogenic variants of INSR. Methods: Despite initial efforts to regulate glycemia with insulin therapy followed by metformin treatment, achieving stable glycemic control presented a critical challenge, characterized by persistent hyperinsulinism and variable fluctuations in glucose levels. Upon the addition of empagliflozin to metformin, notable improvements in glycated hemoglobin (HbA1c) and time in range (TIR) were observed over a 10-month period. Results: After 10 months of treatment, empagliflozin therapy led to a clinically meaningful reduction in HbA1c levels, decreasing from 8.5% to 7.1%, along with an improvement in TIR from 47% to 74%. Furthermore, regular monitoring effectively averted normoglycemic ketoacidosis, a rare complication associated with SGLT2 inhibitor therapy. Conclusion: This case highlights the potential of SGLT2i as adjunctive therapy in RMS management, particularly in stabilizing glycemic variability. However, further research is warranted to elucidate the long-term efficacy and safety of this therapeutic approach in RMS and similar insulin resistance syndromes.
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AIM: Atopic dermatitis (AD) is a common, chronic relapsing inflammatory skin disease characterized by dry skin and variable pruritus sometimes associated with allergic disease in other organs as asthma and rhinoconjunctivitis. AD affects deeply the Quality of Life, thus can be extremely disabling and may cause psychological problems for both affected children and their families. METHODS: In order to investigate the estimated prevalence of the disease and the beliefs of the Italian pediatricians, a group of 437 Italian family pediatricians covering a population of almost 380000 children participated in a study based on a questionnaire of 38 items. RESULTS: According to answers of the participants, the incidence of AD has been estimated around 10% of the population and food allergy is believed to be the trigger of the acute phase of the disease in infants. As a second opinion, dermatologists are consulted more frequently than allergologists. CONCLUSION: The use of emollients is advised in general whilst topical corticosteroids treatment is prescribed only in selected cases; more than 50% of pediatricians do not prescribe topical calcineurin inhibitors.
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Atitude do Pessoal de Saúde , Dermatite Atópica/tratamento farmacológico , Criança , Dermatite Atópica/epidemiologia , Feminino , Hospitais Pediátricos , Humanos , Masculino , Pediatria , Prevalência , Inquéritos e QuestionáriosRESUMO
Cyclin-dependent kinase 12 (CDK12) overexpression is implicated in breast cancer, but whether it has a primary or only a cooperative tumorigenic role is unclear. Here, we show that transgenic CDK12 overexpression in the mouse mammary gland per se is sufficient to drive the emergence of multiple and multifocal tumors, while, in cooperation with known oncogenes, it promotes earlier tumor onset and metastasis. Integrative transcriptomic, metabolomic and functional data reveal that hyperactivation of the serine-glycine-one-carbon network is a metabolic hallmark inherent to CDK12-induced tumorigenesis. Consistently, in retrospective patient cohort studies and in patient-derived xenografts, CDK12-overexpressing breast tumors show positive response to methotrexate-based chemotherapy targeting CDK12-induced metabolic alterations, while being intrinsically refractory to other types of chemotherapy. In a retrospective analysis of hormone receptor-negative and lymph node-positive breast cancer patients randomized in an adjuvant phase III trial to 1-year low-dose metronomic methotrexate-based chemotherapy or no maintenance chemotherapy, a high CDK12 status predicts a dramatic reduction in distant metastasis rate in the chemotherapy-treated vs. not-treated arm. Thus, by coupling tumor progression with metabolic reprogramming, CDK12 creates an actionable vulnerability for breast cancer therapy and might represent a suitable companion biomarker for targeted antimetabolite therapies in human breast cancers.
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Neoplasias da Mama , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carbono , Carcinogênese/genética , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Feminino , Ácido Fólico , Humanos , Metotrexato/uso terapêutico , Camundongos , Estudos RetrospectivosRESUMO
AIMS/HYPOTHESIS: The aim of this study was to investigate the genetic aetiology of permanent diabetes mellitus with onset in the first 12 months of age. METHODS: We studied 46 probands with permanent, insulin-requiring diabetes with onset within the first 6 months of life (permanent neonatal diabetes mellitus [PNDM]/monogenic diabetes of infancy [MDI]) (group 1) and eight participants with diabetes diagnosed between 7 and 12 months of age (group 2). KCNJ11, INS and ABCC8 genes were sequentially sequenced in all patients. For those who were negative in the initial screening, we examined ERN1, CHGA, CHGB and NKX6-1 genes and, in selected probands, CACNA1C, GCK, FOXP3, NEUROG3 and CDK4. The incidence rate for PNDM/MDI was calculated using a database of Italian patients collected from 1995 to 2009. RESULTS: In group 1 we found mutations in KCNJ11, INS and ABCC8 genes in 23 (50%), 9 (19.5%) and 4 (8.6%) patients respectively, and a single homozygous mutation in GCK (2.1%). In group 2, we identified one incidence of a KCNJ11 mutation. No genetic defects were detected in other loci. The incidence rate of PNDM/MDI in Italy is estimated to be 1:210,287. CONCLUSIONS/INTERPRETATION: Genetic mutations were identified in ~75% of non-consanguineous probands with PNDM/MDI, using sequential screening of KCNJ11, INS and ABCC8 genes in infants diagnosed within the first 6 months of age. This percentage decreased to 12% in those with diabetes diagnosed between 7 and 12 months. Patients belonging to the latter group may either carry mutations in genes different from those commonly found in PNDM/MDI or have developed an early-onset form of autoimmune diabetes.
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Diabetes Mellitus/etiologia , Diabetes Mellitus/genética , Transportadores de Cassetes de Ligação de ATP/genética , Diabetes Mellitus/epidemiologia , Feminino , Predisposição Genética para Doença , Quinases do Centro Germinativo , Humanos , Lactente , Recém-Nascido , Insulina/genética , Masculino , Mutação , Canais de Potássio Corretores do Fluxo de Internalização/genética , Proteínas Serina-Treonina Quinases/genética , Receptores de Droga/genética , Receptores de SulfonilureiasRESUMO
Introduction In the past years, we developed a telemonitoring service for young patients affected by Type 1 Diabetes. The service provides data to the clinical staff and offers an important tool to the parents, that are able to oversee in real time their children. The aim of this work was to analyze the parents' perceived usefulness of the service. Methods The service was tested by the parents of 31 children enrolled in a seven-day clinical trial during a summer camp. To study the parents' perception we proposed and analyzed two questionnaires. A baseline questionnaire focused on the daily management and implications of their children's diabetes, while a post-study one measured the perceived benefits of telemonitoring. Questionnaires also included free text comment spaces. Results Analysis of the baseline questionnaires underlined the parents' suffering and fatigue: 51% of total responses showed a negative tendency and the mean value of the perceived quality of life was 64.13 in a 0-100 scale. In the post-study questionnaires about half of the parents believed in a possible improvement adopting telemonitoring. Moreover, the foreseen improvement in quality of life was significant, increasing from 64.13 to 78.39 ( p-value = 0.0001). The analysis of free text comments highlighted an improvement in mood, and parents' commitment was also proved by their willingness to pay for the service (median = 200 euro/year). Discussion A high number of parents appreciated the telemonitoring service and were confident that it could improve communication with physicians as well as the family's own peace of mind.
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Cuidadores/psicologia , Diabetes Mellitus Tipo 1/terapia , Pais/psicologia , Telemedicina/métodos , Atitude Frente a Saúde , Criança , Pré-Escolar , Gerenciamento Clínico , Feminino , Humanos , Masculino , Qualidade de Vida/psicologia , Inquéritos e QuestionáriosRESUMO
AIMS: The aim of the study was to evaluate and compare continuous subcutaneous insulin infusion (CSII) use in pediatric and adult age groups. METHODS: Data were collected with a questionnaire sent by e-mail to CSII-experienced Diabetes Centers. The questionnaire assessed: (1) number of CSII-treated patients; (2) patient demographic data and characteristics; (3) structure and organization of Diabetes Centers providing CSII therapy; (4) pump characteristics (conventional pump, sensor-augmented pump); and (5) CSII dropouts. RESULTS: A total of 217 out of 1093 Italian centers participated: 51 pediatric (23.5 %) and 166 (76.5 %) adult centers (AP). Compared to a survey performed in 2005, there was a significant increase in the number of pediatric units when compared to adult units (112 vs 37 %, respectively, p < 0.05). Pediatric age is characterized by a greater concern for quality of life and injections, and a higher dropout rate (10.6 vs 8.9 %) mainly related to pump wearability and site reactions. A complete diabetes-care team is associated with a superior use of technology (fewer dropouts, increased CGM and advanced bolus use) which is, however, still used in a small percentage of patients. CONCLUSIONS: In Italy, the number of CSII-treated pediatric patients (PP) is growing more significantly when compared to adults. Only 60 % of all patients are using advanced functions and 20 % are using CGMs continuously. This confirms the great interest in diabetes technology that is growing in pediatric diabetologists. However, much improvement is warranted in the organization and specialized training of pediatric, adult and transitional facilities.
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Diabetes Mellitus/tratamento farmacológico , Sistemas de Infusão de Insulina/efeitos adversos , Adolescente , Adulto , Fatores Etários , Criança , Pré-Escolar , Feminino , Humanos , Sistemas de Infusão de Insulina/psicologia , Sistemas de Infusão de Insulina/normas , Itália , Masculino , Pacientes/psicologia , Inquéritos e QuestionáriosRESUMO
Prediction of insulin-dependent diabetes mellitus (IDDM) is still largely based on islet cell antibodies (ICAs), but it may be improved by combined analysis with other humoral markers. We examined autoantibodies to insulin (IAAs), glutamic acid decarboxylase (GAD), and M(r) 37,000 and M(r) 40,000 fragments of islet antigens (37 and 40 kDa) together with ICA subtypes in 101 family members with ICAs > or = 10 Juvenile Diabetes Foundation units (JDF U) followed for up to 14 years, of whom 18 have developed IDDM. Life-table analysis showed a 43% risk of IDDM within 10 years for those with ICAs > or = 10 JDF U, rising to 53% for those with ICAs > or = 20 JDF U. The risk for ICAs > or = 10 JDF U was 62% in the family members in the youngest age quartile (< 13.2 years) and fell with increasing age to 4% in those > 40.7 years of age (P = 0.03). ICAs > or = 10 JDF U combined with IAAs gave a risk of 84% (P = 0.03 compared with IAA-), and ICAs > or = 10 JDF U combined with GAD antibodies gave a risk of 61% (P = 0.018). The risk for ICAs > or = 10 JDF U with antibodies to 37-kDa antigen was 76% (P < 0.0001). Risk increased with the number of autoantibodies, from 8% for ICAs alone to 88% with > or = 3 autoantibodies (14 cases detected) (P < 0.0001). The increased risk associated with multiple antibodies was observed independent of age.(ABSTRACT TRUNCATED AT 250 WORDS)
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Autoanticorpos/sangue , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Ilhotas Pancreáticas/imunologia , Adolescente , Adulto , Criança , Pré-Escolar , Árvores de Decisões , Diabetes Mellitus Tipo 1/enzimologia , Feminino , Seguimentos , Glutamato Descarboxilase/imunologia , Humanos , Tábuas de Vida , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e EspecificidadeRESUMO
OBJECTIVE: Islet cell antibody (ICA) measurements in serum are used for large-scale screening to identify subjects who are at high risk of developing type 1 diabetes. The aim of this study was to adapt measurements to capillary whole blood samples to facilitate and reduce screening costs. RESEARCH DESIGN AND METHODS: GAD65, IA-2, and combined GAD65/IA-2 antibody tests were performed on patients with type 1 diabetes, first-degree relatives of patients, and control subjects, and results from serum, plasma, whole venous blood, and capillary whole blood lysates were compared. Measurements obtained in serum and eluates from dried capillary blood spots from 36 ICA+ first-degree relatives were also compared. RESULTS: GAD65, IA-2, and combined GAD65/IA-2 antibody levels were completely concordant with measurements obtained from serum, plasma, whole venous blood, and capillary whole blood lysates. Antibody levels obtained in eluates from dried capillary blood spots were lower than corresponding serum samples, and weak antibodies were not detected. CONCLUSIONS: Initial screening for diabetes risk can be performed using one drop of capillary whole blood without further processing to separate serum. This method should be considered as a way to simplify and reduce costs of screening programs.
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Autoanticorpos/sangue , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/imunologia , Coleta de Amostras Sanguíneas/métodos , Capilares , Criança , Estudos de Coortes , Diabetes Mellitus Tipo 2/sangue , Família , Glutamato Descarboxilase/imunologia , Humanos , Ilhotas Pancreáticas/imunologia , Valores de Referência , Análise de RegressãoRESUMO
OBJECTIVE: This study has been designed to follow prospectively the GFR and UAE of young patients with short-term IDDM and normal UAE. RESEARCH DESIGN AND METHODS: The study population consisted of 19 patients with glomerular hyperfiltration and 19 patients with normal GFR, matched for duration of diabetes and age. GFR has been assessed by radioisotopic tracer and UAE by RIA at the beginning of the study and after 30.5 +/- 10.4 mo of follow-up. RESULTS: GFR decreased in the two groups btt delta GFR of patients with glomerular hyperfiltration was greater than delta GFR of patients with normal GFR (0.83 +/- 0.55 vs. 0.28 +/- 0.63 ml.min-1.mo-1; P < 0.01). UAE, BP, and prevalence of microalbuminuria were comparable between the two groups at follow-up. Rate of fall of GFR was positively correlated with initial GFR (r = 0.59, P < 0.001) but not with initial UAE, BP, or changes in HbA1C, UAE, BP, or pubertal development during follow-up. CONCLUSIONS: Investigation of kidney function in children and adolescents with IDDM over a 3-yr follow-up period shows that glomerular hyperfiltration is characterized by a greater decline in GFR without an increased rate of appearance of microalbuminuria, than in patients with normal GFR.
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Diabetes Mellitus Tipo 1/fisiopatologia , Taxa de Filtração Glomerular , Glomérulos Renais/fisiopatologia , Adolescente , Albuminúria , Diabetes Mellitus Tipo 1/urina , Nefropatias Diabéticas/prevenção & controle , Feminino , Seguimentos , Humanos , Glomérulos Renais/fisiologia , Masculino , Programas de Rastreamento , Valores de ReferênciaRESUMO
OBJECTIVE: Height and weight changes during the first 3 years of diabetes were prospectively followed in 152 diabetic children and adolescents. RESEARCH DESIGN AND METHODS: The study sample consisted of 152 Caucasian diabetic patients (84 boys; 68 girls) followed from diabetes onset in the Paediatric Diabetes Unit and 80 Caucasian normal subjects (49 boys; 31 girls) assessed in the Outpatient General Paediatric Clinic of the same hospital for routine examination and not affected by problems that might influence growth. Diabetic patients and control subjects were consecutively enrolled in the study between 1989 and 1992; diabetic patients with positive markers for celiac disease (positive antiendomysial antibodies) and thyroid disease (positive antimicrosomial antibodies) or any other chronic disease were not considered in the study. Mean age of diabetic patients (8.9 +/- 4.1 years) and control subjects (8.5 +/- 4.2 years) at recruitment in the study was similar. RESULTS: At onset of diabetes, the mean height expressed as the height standard deviation score (HSDS) was significantly greater than the expected values (P < 0.0001) and was independent of sex and pubertal stage. During the first 3 years of diabetes, HSDS decreased significantly (F = 6.9; P < 0.001). Meanwhile, growth velocity as standard deviation score (SDS) decreased significantly between the 1st and 2nd year (-0.12 +/- 2.1; -0.76 +/- 2.6, respectively; P < 0.05), but it was similar between the 2nd and 3rd year of diabetes. Weight expressed as SDS increased significantly during the first 2 years of diabetes but not thereafter. Height changes during the study period were independent from pubertal stage and sex. Metabolic control and insulin requirement, in our series, were not clearly related to height and weight changes. CONCLUSIONS: Diabetic patients at onset of diabetes are taller than age- and sex-matched nondiabetic subjects. During the first years of the disease, linear growth decreases independently of metabolic control and weight changes.
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Estatura , Peso Corporal , Diabetes Mellitus Tipo 1/fisiopatologia , Crescimento/fisiologia , Adolescente , Idade de Início , Criança , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Estudos Prospectivos , Valores de Referência , Fatores de TempoRESUMO
OBJECTIVE: To examine the performance of islet cell antibodies (ICAs) and antibodies to glutamate decarboxylase (GADA), IA-2 (IA-2 antibody [IA-2A]), and insulin (insulin autoantibody [IAA]), alone and in combination, in assessing type 1 diabetes risk within type 1 diabetic families to identify a practical and effective screening strategy for predicting type 1 diabetes in relatives. RESEARCH DESIGN AND METHODS: ICA, GADA, IA-2A, and IAA were determined in 806 first-degree relatives participating in a prospective type 1 diabetes family study (median follow-up 6.17 years, range 0.6-8.3). The conferred risk of developing type 1 diabetes within 6 years was evaluated by Kaplan-Meier for each antibody marker, used alone or in combination. RESULTS: ICAs were detected in 3%, GADA in 5.1%, IA-2A in 2.5%, and IAA in 3.7% of relatives; > or =1 antibody markers were detected in 10.7% of relatives and > or =2 were detected in 1.9% of relatives. The risk of type 1 diabetes at 6 years was 1.5% in relatives with only 1 marker and 24.8% in relatives with > or =2 markers. As a practical and effective strategy for type 1 diabetes risk assessment in relatives, this study indicates a first-step screening based on GADA and IA-2A measurement--which identified 6.5% of relatives, including all who developed the disease, with a 6-year type 1 diabetes risk of 9.0%--followed by a second step based on ICA and IAA measurement in relatives with either GADA or IA-2A, which identified a total of 1.9% of all relatives as having > or =2 markers, and a 6-year risk of 24.8%, including 6 of 7 who developed type 1 diabetes. CONCLUSIONS: A two-step antibody screening, based first on GADA and IA-2A and then on ICA and IAA measurements in identified individuals, is likely to be a practical, sensitive, and effective strategy for predicting type 1 diabetes in first-degree relatives.
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Autoanticorpos/análise , Diabetes Mellitus Tipo 1/diagnóstico , Ilhotas Pancreáticas/imunologia , Adulto , Biomarcadores , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/genética , Família , Glutamato Descarboxilase/imunologia , Humanos , Insulina/imunologia , Prevalência , Fatores de RiscoRESUMO
Data on growth of children with insulin-dependent diabetes mellitus (IDDM) before the onset of disease are conflicting, and although the insulin-like growth factor (IGF) system has almost invariably been found altered at diagnosis, most of previous studies are affected by the small number of patients investigated. We studied 60 IDDM children at the onset of disease, comparing their stature with target height, normal growth standards, and height of 102 sex- and age-matched controls. Furthermore, we assessed serum IGF-I, IGF-II, and IGF-binding protein-3 (IGFBP-3) levels and IGFBP-3 circulating forms. IDDM children were subdivided into 2 groups according to an age above (n = 26) or below (n = 34) 6 yr. The values of endocrine variables of diabetics older than 6 yr were compared with those of 34 age-matched controls. Although the height of diabetics was higher than growth reference values (mean height +/- SD, 0.64+/-1.4 z-score) and their target height (mean target height +/- SD, 0.1+/-0.84 z-score; P < 0.005), no significant difference in height was found between IDDM children and controls (mean height +/- SD, 0.64+/-0.95 z-score) even analyzing the 2 age groups separately. Overall, IDDM children showed reduced levels of IGF-I (mean +/- SD, -0.65+/-1.9 z-score) and normal levels of IGF-II (mean +/- SD, -0.05+/-1.2 z-score) and IGFBP-3 (mean +/- SD, -0.06+/-1.2 z-score). However, whereas patients younger than 6 yr showed normal values of IGF-I, IGF-II, and IGFBP-3, these peptides were significantly reduced in older subjects compared with either younger IDDM children or controls (P < 0.01). IGFBP-3 immunoblot analysis revealed the presence of an approximately 18-kDa fragment of IGFBP-3 in addition to the major approximately 29-kDa fragment and the intact form (approximately 42-39 kDa) in 46 of 60 IDDM patients, whereas the approximately 18-kDa band was absent in all 34 control sera. No relationship was found between the endocrine variables and stature at diagnosis. In conclusion, our results indicate that IDDM children at the onset of disease are not taller than healthy peers and have increased IGFBP-3 proteolytic activity. Finally, although the IGF system is normal in younger IDDM children, older patients have reduced IGF levels.
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Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/fisiopatologia , Crescimento , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Idade de Início , Estatura , Peptídeo C/sangue , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Hidrocortisona/sangue , Fator de Crescimento Insulin-Like I/análise , Fator de Crescimento Insulin-Like II/análise , Masculino , Peso Molecular , Valores de ReferênciaRESUMO
Endothelial cells are the principal source of plasma and basement membrane von Willebrand factor (vWF). To arrive at its biologically active multimeric form, vWF undergoes a series of intracellular processing steps. The protein is synthesized as a large precursor pro-vWF, which dimerizes in the endoplasmic reticulum through disulfide bonds located in the carboxyl-terminal portion of the subunit. Only dimers are transported to the Golgi apparatus. Expression of truncated pro-vWF subunits, which lack the last 20 kd, abolishes the requirement for dimerization and thereby allows the monomeric protein to be secreted. Another requirement for intracellular transport from the endoplasmic reticulum is N-linked glycosylation. Inhibition of N-linked glycosylation prevents exit of both the wild-type and the truncated vWF from the endoplasmic reticulum. In the acidic environment of the trans-Golgi and post-Golgi compartments, pro-vWF dimers multimerize by a second set of interchain disulfide bonds. The presence of the vWF propolypeptide and acidic pH conditions are necessary for the multimerization process. The largest vWF multimers are stored in endothelial cell-specific organelles called Weibel-Palade bodies. At the site of vascular injury and inflammation, physiologic secretagogues such as thrombin, fibrin, and histamine may cause release of these large, biologically potent vWF multimers from the Weibel-Palade bodies into the surrounding blood and subendothelium.