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1.
Phys Rev Lett ; 132(12): 122701, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38579210

RESUMO

^{140}Ce(n,γ) is a key reaction for slow neutron-capture (s-process) nucleosynthesis due to being a bottleneck in the reaction flow. For this reason, it was measured with high accuracy (uncertainty ≈5%) at the n_TOF facility, with an unprecedented combination of a high purity sample and low neutron-sensitivity detectors. The measured Maxwellian averaged cross section is up to 40% higher than previously accepted values. Stellar model calculations indicate a reduction around 20% of the s-process contribution to the Galactic cerium abundance and smaller sizeable differences for most of the heavier elements. No variations are found in the nucleosynthesis from massive stars.

2.
Phys Rev Lett ; 131(3): 031802, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37540851

RESUMO

We report the direct observation of muon neutrino interactions with the SND@LHC detector at the Large Hadron Collider. A dataset of proton-proton collisions at sqrt[s]=13.6 TeV collected by SND@LHC in 2022 is used, corresponding to an integrated luminosity of 36.8 fb^{-1}. The search is based on information from the active electronic components of the SND@LHC detector, which covers the pseudorapidity region of 7.2<η<8.4, inaccessible to the other experiments at the collider. Muon neutrino candidates are identified through their charged-current interaction topology, with a track propagating through the entire length of the muon detector. After selection cuts, 8 ν_{µ} interaction candidate events remain with an estimated background of 0.086 events, yielding a significance of about 7 standard deviations for the observed ν_{µ} signal.

3.
Eur Phys J A Hadron Nucl ; 58(12): 239, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36514540

RESUMO

Neutron capture reaction cross sections on 74 Ge are of importance to determine 74 Ge production during the astrophysical slow neutron capture process. We present new resonance data on 74 Ge( n , γ ) reactions below 70 keV neutron energy. We calculate Maxwellian averaged cross sections, combining our data below 70 keV with evaluated cross sections at higher neutron energies. Our stellar cross sections are in agreement with a previous activation measurement performed at Forschungszentrum Karlsruhe by Marganiec et al., once their data has been re-normalised to account for an update in the reference cross section used in that experiment.

4.
Phys Rev Lett ; 125(14): 142701, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33064503

RESUMO

The neutron capture cross sections of several unstable nuclides acting as branching points in the s process are crucial for stellar nucleosynthesis studies. The unstable ^{171}Tm (t_{1/2}=1.92 yr) is part of the branching around mass A∼170 but its neutron capture cross section as a function of the neutron energy is not known to date. In this work, following the production for the first time of more than 5 mg of ^{171}Tm at the high-flux reactor Institut Laue-Langevin in France, a sample was produced at the Paul Scherrer Institute in Switzerland. Two complementary experiments were carried out at the neutron time-of-flight facility (n_TOF) at CERN in Switzerland and at the SARAF liquid lithium target facility at Soreq Nuclear Research Center in Israel by time of flight and activation, respectively. The result of the time-of-flight experiment consists of the first ever set of resonance parameters and the corresponding average resonance parameters, allowing us to make an estimation of the Maxwellian-averaged cross sections (MACS) by extrapolation. The activation measurement provides a direct and more precise measurement of the MACS at 30 keV: 384(40) mb, with which the estimation from the n_TOF data agree at the limit of 1 standard deviation. This value is 2.6 times lower than the JEFF-3.3 and ENDF/B-VIII evaluations, 25% lower than that of the Bao et al. compilation, and 1.6 times larger than the value recommended in the KADoNiS (v1) database, based on the only previous experiment. Our result affects the nucleosynthesis at the A∼170 branching, namely, the ^{171}Yb abundance increases in the material lost by asymptotic giant branch stars, providing a better match to the available pre-solar SiC grain measurements compared to the calculations based on the current JEFF-3.3 model-based evaluation.

5.
Phys Rev Lett ; 121(4): 042701, 2018 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-30095928

RESUMO

We report on the measurement of the ^{7}Be(n,p)^{7}Li cross section from thermal to approximately 325 keV neutron energy, performed in the high-flux experimental area (EAR2) of the n_TOF facility at CERN. This reaction plays a key role in the lithium yield of the big bang nucleosynthesis (BBN) for standard cosmology. The only two previous time-of-flight measurements performed on this reaction did not cover the energy window of interest for BBN, and they showed a large discrepancy between each other. The measurement was performed with a Si telescope and a high-purity sample produced by implantation of a ^{7}Be ion beam at the ISOLDE facility at CERN. While a significantly higher cross section is found at low energy, relative to current evaluations, in the region of BBN interest, the present results are consistent with the values inferred from the time-reversal ^{7}Li(p,n)^{7}Be reaction, thus yielding only a relatively minor improvement on the so-called cosmological lithium problem. The relevance of these results on the near-threshold neutron production in the p+^{7}Li reaction is also discussed.

6.
Diabet Med ; 34(5): 621-624, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27885706

RESUMO

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.


Assuntos
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 Retrospectivos
7.
Phys Rev Lett ; 117(15): 152701, 2016 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-27768364

RESUMO

The energy-dependent cross section of the ^{7}Be(n,α)^{4}He reaction, of interest for the so-called cosmological lithium problem in big bang nucleosynthesis, has been measured for the first time from 10 meV to 10 keV neutron energy. The challenges posed by the short half-life of ^{7}Be and by the low reaction cross section have been overcome at n_TOF thanks to an unprecedented combination of the extremely high luminosity and good resolution of the neutron beam in the new experimental area (EAR2) of the n_TOF facility at CERN, the availability of a sufficient amount of chemically pure ^{7}Be, and a specifically designed experimental setup. Coincidences between the two alpha particles have been recorded in two Si-^{7}Be-Si arrays placed directly in the neutron beam. The present results are consistent, at thermal neutron energy, with the only previous measurement performed in the 1960s at a nuclear reactor. The energy dependence reported here clearly indicates the inadequacy of the cross section estimates currently used in BBN calculations. Although new measurements at higher neutron energy may still be needed, the n_TOF results hint at a minor role of this reaction in BBN, leaving the long-standing cosmological lithium problem unsolved.

8.
Eur J Paediatr Dent ; 16(4): 290-4, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26637252

RESUMO

BACKGROUND: When treating children, a conservative and minimally invasive approach is mandatory. In dental traumas with partial coronal destruction, veneers represent the fastest and most effective method to rehabilitate front teeth of a young patient, since these no- or minimal-preparation restorations were proved to have predictable results without reducing the enamel layer. Indirect additive anterior composite restorations, besides being quick and minimally invasive, have to be considered a good treatment option for rehabilitating children, because they are inexpensive and repairable over time. Current laboratory techniques, associated with a strict clinical protocol, satisfy patients' restorative and aesthetic needs in few appointments and in a short time. CASE REPORT: The cases reported describe the minimally invasive treatment of two lateral incisors with nano-hybrid resin composite veneers after traumatic events. The patient satisfaction and good integration of indirect restorations confirmed the success of this rehabilitation.


Assuntos
Resinas Compostas , Facetas Dentárias , Traumatismos Dentários/reabilitação , Criança , Técnica de Moldagem Odontológica , Humanos , Masculino
9.
Phys Rev Lett ; 110(2): 022501, 2013 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-23383895

RESUMO

The 63Ni(n,γ) cross section has been measured for the first time at the neutron time-of-flight facility n_TOF at CERN from thermal neutron energies up to 200 keV. In total, capture kernels of 12 (new) resonances were determined. Maxwellian averaged cross sections were calculated for thermal energies from kT=5-100 keV with uncertainties around 20%. Stellar model calculations for a 25M⊙ star show that the new data have a significant effect on the s-process production of 63Cu, 64Ni, and 64Zn in massive stars, allowing stronger constraints on the Cu yields from explosive nucleosynthesis in the subsequent supernova.

10.
Nutr Metab Cardiovasc Dis ; 23(10): 1031-6, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23466181

RESUMO

BACKGROUND AND AIMS: Type 1 diabetes (T1DM) affects young people during the most active years of their life. Our aim was to assess quality of life (QoL) and associated variables in a large cohort of adults with childhood-onset and adult-onset T1DM. METHODS: A cohort of adult patients (18 years and older) from the T1DM Registry of Turin, Italy, was recruited. Clinical characteristics and Diabetes QoL (DQOL) questionnaire were assessed by standardized procedures. RESULTS: 310 adults completed the questionnaire. Age and diabetes duration at assessment (mean ± SD) were 32.8 ± 7.3 years and 17.3 ± 6.3 years, respectively. DQOL and its subscores were in the lower quartiles of their distributions, indicating a good level of QoL. However, scores were significantly higher in females than in males, particularly for the subscale of diabetes-related worries. In multivariate analysis, lower QoL was independently associated with female sex (ß = 1.07, 95% CI 1.03-1.11, p = 0.003), higher age at onset (ß = 1.03, 1.00-1.05, p = 0.009), lower schooling (ß = 1.05, 1.00-1.09, p = 0.02), higher fasting plasma glucose (ß = 1.03, 1.01-1.05, p = 0.008), daily SMBG >4 (ß = 1.06, 1.01-1.10, p = 0.01), severe hypoglycemia over the last year (ß = 1.06, 1.01-1.11, p = 0.02), lower numbers of diabetologic visits (ß = 1.07, 1.01-1.13, p = 0.02) and hypertension (ß = 1.06, 1.02-1.10, p = 0.005). Autonomic neuropathy was associated with diabetes impact. Female sex (ß = 4.36, 2.43-7.83) and daily SMBG >4 (ß = 3.77, 1.72-8.30) were independently associated with worst level and CSII with better level (ß = 0.22, 0.07-0.68) of diabetes-related worries. CONCLUSIONS: The impact of T1DM on QoL may depend on demographic, metabolic control-related variables, presence of complications and insulin delivery modality.


Assuntos
Envelhecimento , Atitude Frente a Saúde , Complicações do Diabetes/epidemiologia , Diabetes Mellitus Tipo 1/epidemiologia , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Qualidade de Vida , Adulto , Idade de Início , Estudos de Coortes , Efeitos Psicossociais da Doença , Estudos Transversais , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/tratamento farmacológico , Feminino , Seguimentos , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Autorrelato , Caracteres Sexuais , Adulto Jovem
11.
Minerva Stomatol ; 61(3): 65-73, 2012 Mar.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-22402297

RESUMO

AIM: Aim of this study was to evaluate two different luting cements and how their clinical procedures influence the postcementation quality. METHODS: Thirty-six freshly extracted mono-radicular teeth (N.=18) were treated endodontically and randomly divided into two groups. Posts were cemented respectively with two different self adhesive luting cements: Group A - RelyX Unicem (3M Espe) and Group B - Multilink Sprint (Ivoclar-Vivadent) following the manufacturers' instructions. Teeth were then thermocycled according to protocol ISO/TR 11405 and were immersed 24 hours in 2% methylene-blue solution. Each tooth was sectioned by a diamond-coated saw (Isomet-Buhler) from CEJ to apex. Each slice was examined for the presence or absence of gutta-percha remnants, voids, bubbles, dye infiltration degree and polymerization grade of the luting agent. Findings were evidenced by stereoscopic microscopy (30x) and Micro-Raman spectroscopy. Mann-Whitney and ANOVA statistical analyses were performed for all results. RESULTS: No statistical significances were evidenced for gutta-percha presence, dye infiltration and polymerization degree. Voids were present mostly in Group B and bubbles in Group A. Both differences were statistically significant. CONCLUSION: Materials and protocols for glass fiber posts cementation are fundamental for the clinical success. Self adhesive luting cements, if used correctly, could be an acceptable and quick luting agent for postcementation.


Assuntos
Cimentação/métodos , Cimentos Dentários , Materiais Dentários , Adesivos Dentinários , Vidro , Polimerização , Cimentos de Resina , Humanos , Técnicas In Vitro
12.
Diabetologia ; 54(7): 1693-701, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21544516

RESUMO

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.


Assuntos
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 Sulfonilureias
13.
Pediatr Diabetes ; 12(5): 485-93, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21457424

RESUMO

OBJECTIVE: To determine how Italian parents and school personnel of 6-13-year-old children with type 1 diabetes (T1D) manage during school hours, including insulin administration, management of hypoglycemia, and glucagon use. A further aim was an investigation into the responsibilities and training of school personnel regarding diabetes. RESEARCH DESIGN AND METHODS: After an initial qualitative phase, semi-structured questionnaires were completed by a sample of parents and teachers. RESULTS: 220 parent and 52 teacher questionnaires were completed. 43.6% of parents said diabetes had negatively influenced school activities. Children either self-administer insulin, or have help from a parent, since there is very rarely a nurse present (3.6%) or a teacher who will take responsibility for the treatment (2.9%). Most parents (55.9%) stated either that the school had no refrigerator to store glucagon or that they did not know if the school was so equipped. A small percentage of teachers considered their schools to be equipped to manage an emergency (23%) and said they would use glucagon directly in an emergency (14.9%). Only 40.4% of teachers said that they had received any specific training. CONCLUSIONS: The study shows that people who are not directly involved have superficial knowledge of the different aspects of diabetes, even though no parents reported episodes of neglect/incorrect management. There is no legislation which clearly defines the role of the school in the care of children with T1D, and teachers are not trained to help them. Training sessions for school personnel and greater legislative clarity about the 'insulin and glucagon question' are key factors that may improve the full integration of the child with diabetes.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/psicologia , Gerenciamento Clínico , Docentes , Necessidades e Demandas de Serviços de Saúde , Instituições Acadêmicas , Adolescente , Atitude Frente a Saúde , Criança , Medo , Glucagon/uso terapêutico , Humanos , Hiperglicemia/terapia , Hipoglicemia/terapia , Insulina/uso terapêutico , Itália , Pais , Inquéritos e Questionários
14.
Int J Immunopathol Pharmacol ; 23(1): 263-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20378012

RESUMO

Secreted phosphoprotein 1, also known as Osteopontin (Opn), is a proinflammatory cytokine involved in the TH1 response and is highly expressed in the islets and pancreatic lymph nodes of non-obese diabetic mice before the onset of diabetes. In humans, typing of the +1239A/C single nucleotide polymorphism (SNP) in the 3UTR of the Opn gene (SPP1) showed that +1239C carriers displayed higher Opn serum levels than +1239A homozygotes and a higher risk of developing autoimmune/lymphoproliferative syndrome, multiple sclerosis, and systemic lupus erythematosus. The aim of this work is to evaluate whether +1239A/C is also associated with type 1 diabetes mellitus (T1DM). We typed +1239A/C in an initial cohort of 184 T1DM patients and 361 controls, and confirmed our data in a second cohort of 513 patients and 857 controls. In both cohorts, +1239C carriers displayed a significantly higher risk of T1DM than +1239A homozygotes (combined cohorts: OR=1.63, 95 percent CI: 1.34-1.97). Clinical analysis did not detect any differences between patients carrying or not +1239C in terms of gender distribution and age at T1DM diagnosis. These data suggest that SPP1 variants marked by +1239C are associated with T1DM development in the Italian population. The predisposing effect may depend on its effect on Opn levels.


Assuntos
Diabetes Mellitus Tipo 1/genética , Osteopontina/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Criança , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Antígenos HLA-DQ/química , Antígenos HLA-DQ/genética , Cadeias alfa de HLA-DQ , Cadeias beta de HLA-DQ , Humanos , Masculino , Multimerização Proteica
15.
Nutr Metab Cardiovasc Dis ; 20(4): 266-73, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19748246

RESUMO

BACKGROUND AND AIM: The prevalence of children with hypertension is increasing, especially in obese children. This study was to assess the relationship between blood pressure, indexes of adiposity, body fat distribution and insulin resistance. SAMPLE: 1044 children (M/F: 484/560; aged 6-11 years). Anthropometry and blood pressure were measured and fasting blood samples were tested for triacylglycerol, total cholesterol, HDL cholesterol, glucose, insulin and ALT. The prevalence of high blood pressure in overweight males and females was 14.3 and 6.4%, respectively (chi(2)=16.73, p<0.001) and in obese it was 40.4 and 32.8%, respectively (chi(2)=5.56, p<0.001). High blood pressure increased progressively with BMI z-score categories (chi(2)=67.99, p<0.001) as well as with waist/height ratio (W/Hr) categories (chi(2)=23.51, p<0.001). Hypertensive subject had significantly higher insulin (15.6+/-9.8 vs 11.9+/-7.2, p<0.001 and 20.63+/-14.7 vs 15.26+/-9.8, p<0.001 in males and females respectively) and HOMA(IR) (3.23+/-2.1 vs 2.42+/-1.49, p<0.001 and 4.12+/-2.87 vs 3.07+/-1.98, p<0.001 in males and in females, respectively) than non-hypertensive ones. Among metabolic and cardiovascular risk factors, HOMA(IR) was the only variable able to predict high blood pressure in obese boys and girls, in addition to BMI or body fat distribution (waist, W/Hr). The highest HOMA(IR) category was the most important predicting factor of high blood pressure in overweight and obese children in addition to body size or body fat distribution. CONCLUSIONS: Blood pressure is associated with the degree of overweight and the indices of body fat distribution. Insulin resistance is an independent additional risk factor for hypertension.


Assuntos
Adiposidade/fisiologia , Peso Corporal/fisiologia , Hipertensão/epidemiologia , Resistência à Insulina/fisiologia , Obesidade/complicações , Obesidade/fisiopatologia , Pressão Sanguínea/fisiologia , Índice de Massa Corporal , Criança , Feminino , Humanos , Modelos Logísticos , Masculino , Razão de Chances , Sobrepeso/fisiopatologia , Puberdade/fisiologia , Fatores de Risco , Circunferência da Cintura
16.
J Endocrinol Invest ; 33(8): 539-43, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20160470

RESUMO

UNLABELLED: The aim of this study was to assess the behaviour of insulin sensitivity and insulin resistance (IR) indexes in a group of obese adolescents with Type 2 diabetes mellitus (T2DM) in comparison to obese adolescents without diabetes and normal controls, moreover to compare these parameters with the cardiac autonomic pattern. Seven T2DM obese (12.7 ± 0.5 yr), 18 obese without T2DM, and 10 nonobese control adolescents age matched were studied. In all subjects we performed oral glucose tolerance test (OGTT) with insulin and glucose determination, 24-h electrocardiogram Holter, blood pressure monitoring, ecohocardiogram. RESULTS: serum lipids were significantly higher in obese and T2DM. Insulin sensitivity was significantly reduced in T2DM and obese vs controls; T2DM showed a more pronounced oral glucose insulin sensitivity (OGIS) reduction vs obese. Both obese and T2DM presented an higher IR. T2DM showed an impaired ß-cell function, with insulin areas under the curve and disposition index significantly reduced in comparison to controls and obese who showed similar values. A progressive reduction of vagal indexes and an increase of sympathetic indexes were found in obese adolescents and were more pronounced in T2DM. These parameters were correlated with OGIS and ß-cell function parameters in both obese and T2DM adolescents. T2DM showed a significant relative wall thickness increase suggesting a trend toward concentric remodeling. In conclusion, T2DM adolescents are characterized by a more marked IR reduced ß-cell function in comparison to non-diabetic obese. These modifications may lead to an early impairment of the autonomic pattern.


Assuntos
Sistema Cardiovascular/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Resistência à Insulina/fisiologia , Células Secretoras de Insulina/fisiologia , Obesidade/complicações , Adolescente , Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea , Criança , Ecocardiografia , Eletrocardiografia Ambulatorial , Feminino , Teste de Tolerância a Glucose , Humanos , Lipídeos/sangue , Obesidade/fisiopatologia
17.
Diabetologia ; 52(12): 2531-5, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19821110

RESUMO

AIMS/HYPOTHESIS: A shift towards younger age at onset of diabetes in susceptible people has been suggested as a possible explanation for the increasing temporal trend in incidence of type 1 diabetes. We aimed to test this hypothesis by assessing trends in incidence rates in the period 1984-2004 in children and young adults in Northern Italy. METHODS: The study bases were: (1) children resident in the Province of Turin in the period 1984-2004 and in the remaining areas of the Piedmont Region in the period 1990-2004; and (2) young adults (15-29 years) resident in the Province of Turin in the period 1984-2003. Temporal trends in rates were analysed using Poisson regression models. RESULTS: A total of 1,773 incident cases were identified. Overall incidence rates/100,000 person-years in the age groups 0-14 and 15-29 years were 11.3 (95% CI 10.7-12.0) and 7.1 (95% CI 6.6-7.7), respectively, with sex differences among young adults only (incidence rate ratio [IRR] in males vs females 1.41 [95% CI 1.20-1.64]). Average annual increases in incidence rates were similar in children and young adults at 3.3% (95% CI 2.5-4.1). Compared with the period 1984-89, in 2000-2004 a 60% higher risk was found in both age 0-14 years (IRR 1.60, 95% CI 1.31-1.95) and 15-29 years (IRR 1.57, 95% CI 1.26-1.96) groups. The Poisson modelling showed no interaction between calendar period and age at onset. CONCLUSIONS/INTERPRETATION: Incidence of type 1 diabetes in Northern Italy is increasing over time in both children and young adults, not supporting the hypothesis of a shift towards younger age as the main explanation for the increasing temporal trend in children.


Assuntos
Diabetes Mellitus Tipo 1/epidemiologia , Adolescente , Adulto , Fatores Etários , Idade de Início , Criança , Pré-Escolar , Demografia , Feminino , Humanos , Incidência , Lactente , Itália/epidemiologia , Masculino , Análise de Regressão , Caracteres Sexuais , Fatores de Tempo , Adulto Jovem
18.
Cytogenet Genome Res ; 126(1-2): 165-72, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20016166

RESUMO

Horses, asses and zebras belong to the genus Equus and are the only extant species of the family Equidae in the order Perissodactyla. In a previous work we demonstrated that a key factor in the rapid karyotypic evolution of this genus was evolutionary centromere repositioning, that is, the shift of the centromeric function to a new position without alteration of the order of markers along the chromosome. In search of previously undiscovered evolutionarily new centromeres, we traced the phylogeny of horse chromosome 5, analyzing the order of BAC markers, derived from a horse genomic library, in 7 Equus species (E. caballus, E. hemionus onager, E. kiang, E. asinus, E. grevyi, E. burchelli and E. zebra hartmannae). This analysis showed that repositioned centromeres are present in E. asinus (domestic donkey, EAS) chromosome 16 and in E. burchelli (Burchell's zebra, EBU) chromosome 17, confirming that centromere repositioning is a strikingly frequent phenomenon in this genus. The observation that the neocentromeres in EAS16 and EBU17 are in the same chromosomal position suggests that they may derive from the same event and therefore, E. asinus and E. burchelli may be more closely related than previously proposed; alternatively, 2 centromere repositioning events, involving the same chromosomal region, may have occurred independently in different lineages, pointing to the possible existence of hot spots for neocentromere formation. Our comparative analysis also showed that, while E. caballus chromosome 5 seems to represent the ancestral configuration, centric fission followed by independent fusion events gave rise to 3 different submetacentric chromosomes in other Equus lineages.


Assuntos
Centrômero , Mapeamento Cromossômico , Cavalos/genética , Filogenia , Animais , Cromossomos Artificiais Bacterianos , Sondas de DNA , Hibridização in Situ Fluorescente
19.
Phys Med Biol ; 54(13): 3979-96, 2009 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-19494424

RESUMO

(16)O and (12)C ion beams will be used-besides lighter ions-for cancer treatment at the Heidelberg Ion Therapy Center (HIT), Germany. It is planned to monitor the treatment by means of in-beam positron emission tomography (PET) as it is done for therapy with (12)C beams at the experimental facility at the Gesellschaft für Schwerionenforschung (GSI), Darmstadt, Germany. To enable PET also for (16)O beams, experimental data of the beta(+)-activity created by these beams are needed. Therefore, in-beam PET measurements of the activity created by (16)O beams of various energies on targets of PMMA, water and graphite were performed at GSI for the first time. Additionally reference measurements of (12)C beams on the same target materials were done. The results of the measurements are presented. The deduction of clinically relevant results from in-beam PET data requires reliable simulations of the beta(+)-activity production, which is done presently by a dedicated code limited to (12)C beams. Because this code is not extendable to other ions in an easy way, a new code, capable of simulating the production of the beta(+)-activity by all ions of interest, is needed. Our choice is the general purpose Monte Carlo code FLUKA which was used to simulate the ion transport, the beta(+)-active isotope production, the decay, the positron annihilation and the transport of the annihilation photons. The detector response was simulated with an established software that gives the output in the same list-mode data format as in the experiment. This allows us to use the same software to reconstruct measured and simulated data, which makes comparisons easier and more reliable. The calculated activity distribution shows general good agreement with the measurements.


Assuntos
Carbono/análise , Interpretação de Imagem Assistida por Computador/métodos , Modelos Estatísticos , Oxigênio/análise , Tomografia por Emissão de Pósitrons/métodos , Radiometria/métodos , Radioterapia de Alta Energia/métodos , Simulação por Computador , Humanos , Interpretação de Imagem Assistida por Computador/instrumentação , Método de Monte Carlo , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Nutr Metab Cardiovasc Dis ; 19(5): 340-4, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18674891

RESUMO

Short-term mortality risk in young diabetic people is an indicator of quality of care. We assessed this in the Italian incident population-based registry of Turin. The study base included 1210 incident cases (n=677 aged 0-14 years and n=533 aged 15-29 years) with diabetes, onset period 1974-2000 in the Province of Turin, Italy. The relevant timescale for analysis was the time since the onset of diabetes to death, or till 31 December 2003. Standardized mortality ratio (SMR) for all-cause mortality was computed using the Italian population as a standard, by 5 years, age group, sex, and calendar period. Mean attained age of the incident cohort was 29.7 years (range 5.2-49.7 years). During a mean follow-up period of 15.8 years (range 2.0-29.9 years), there were 19 deaths in 15,967. Nine person-years of observation (n=9.5 expected deaths), giving an all-cause mortality rate of 1.19/1000 person-years (95% CI 0.76-1.87) and an SMR of 1.96 (1.25-3.08). In no cases did death occur at the onset of diabetes or in childhood. Out of 19 deaths, 9 were diabetes related (n=6 coma and n=3 end-stage renal disease). In Cox regression analysis, the hazard ratio (HR) was higher in adult-onset than in childhood-onset diabetes (HR=3.90, 95% CI 1.14-13.39), independently of calendar period and gender. (1) Children and young adults with type 1 diabetes experienced a two-fold higher short-term mortality risk than Italian people of similar age and sex and (2) the risk was higher in adult-onset than in childhood-onset diabetes. The quality of diabetes care should be improved to prevent early deaths.


Assuntos
Diabetes Mellitus Tipo 1/mortalidade , Coma Diabético/mortalidade , Falência Renal Crônica/mortalidade , Qualidade da Assistência à Saúde , Sistema de Registros/estatística & dados numéricos , Adolescente , Adulto , Causas de Morte , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/complicações , Coma Diabético/etiologia , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/mortalidade , Feminino , Humanos , Lactente , Recém-Nascido , Itália , Falência Renal Crônica/etiologia , Masculino , Modelos de Riscos Proporcionais , Adulto Jovem
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