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1.
Nutr Metab Cardiovasc Dis ; 28(5): 436-443, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29609864

RESUMO

AIMS: Hyperinsulinemia is a recognized risk factor for cancer and plays a major role for the increased cancer incidence in diabetic patients. Whether insulin analogs, and particularly long-acting analogs, worsen the pro-cancer effect of excess insulin is still controversial. DATA SYNTHESIS: In this paper we summarize the biological bases for the potential detrimental effect of long-acting analogs on cancer cells and review the in vitro and in vivo evidence on this issue. Because of their different molecular structure relative to native insulin, insulin analogs may activate the insulin receptor (IR) and the post receptor pathways differently. Most, but not all, in vitro evidence indicate that long-acting analogs may have a stronger mitogenic potency than insulin on cancer cells. Notably insulin glargine, the most studied long-acting analog, also has a higher affinity for the insulin-like growth factor (IGF)-1 receptor, a potent growth mediator. In vitro observations, however, may not reflect what occurs in vivo when analogs are metabolized to derivatives with a different mitogenic activity. Clinical studies, mostly retrospective and predominantly concerning glargine, provide contrasting results. The only perspective trial found no cancer increase in patients treated with glargine. All these studies, however, have severe weaknesses because of the insufficient evaluation of important factors such as dose administered, length of exposure, patient follow-up duration and site-specific cancer investigation. Moreover, whether cancer promotion is a long-acting analog class characteristic or a specific effect of a single agent is not clear. CONCLUSIONS: In conclusion the carcinogenic risk of long-acting analogs, and specifically glargine, can be neither confirmed nor excluded. A personalized and shared decision, considering all the individual risk factors (metabolic and non-metabolic), is the suggestion for the clinician.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus/tratamento farmacológico , Hiperinsulinismo/epidemiologia , Hipoglicemiantes/uso terapêutico , Insulina Glargina/uso terapêutico , Neoplasias/epidemiologia , Animais , Biomarcadores/sangue , Glicemia/metabolismo , Tomada de Decisão Clínica , Diabetes Mellitus/sangue , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Humanos , Hiperinsulinismo/induzido quimicamente , Hiperinsulinismo/diagnóstico , Hipoglicemiantes/efeitos adversos , Incidência , Insulina Glargina/efeitos adversos , Neoplasias/induzido quimicamente , Neoplasias/diagnóstico , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
2.
Eur J Nutr ; 57(2): 679-688, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28004268

RESUMO

PURPOSE: Proper evaluation of polyphenols intake at the population level is a necessary step in order to establish possible associations with health outcomes. Available data are limited, and so far no study has been performed in people with diabetes. The aim of this work was to document the intake of polyphenols and their major food sources in a cohort of people with type 2 diabetes and in socio-demographic subgroups. METHODS: We studied 2573 men and women aged 50-75 years. Among others, anthropometry was measured by standard protocol and dietary habits were investigated by food frequency questionnaire (EPIC). The intake of polyphenols was evaluated using US Department of Agriculture and Phenol-Explorer databases. RESULTS: The mean total polyphenol intake was 683.3 ± 5.8 mg/day. Non-alcoholic beverages represented the main food source of dietary polyphenols and provided 35.5% of total polyphenol intake, followed by fruits (23.0%), alcoholic beverages (14.0%), vegetables (12.4%), cereal products and tubers (4.6%), legumes (3.7%) and oils (2.1%); chocolate, cakes and nuts are negligible sources of polyphenols in this cohort. The two most important polyphenol classes contributing to the total intake were flavonoids (47.5%) and phenolic acids (47.4%). Polyphenol intake increased with age and education level and decreased with BMI; furthermore, in the northern regions of Italy, the polyphenol intake was slightly, but significantly higher than in the central or southern regions. CONCLUSIONS: The study documents for the first time the intake of polyphenols and their main food sources in people with diabetes using validated and complete databases of the polyphenol content of food. Compared with published data, collected in people without diabetes, these results suggest a lower intake and a different pattern of intake in people with diabetes.


Assuntos
Antioxidantes/administração & dosagem , Diabetes Mellitus Tipo 2/dietoterapia , Dieta para Diabéticos , Dieta Saudável , Flavonoides/administração & dosagem , Cooperação do Paciente , Fenóis/administração & dosagem , Idoso , Antioxidantes/análise , Bebidas/análise , Cinamatos/administração & dosagem , Cinamatos/análise , Estudos de Coortes , Estudos Transversais , Bases de Dados Factuais , Diabetes Mellitus Tipo 2/etnologia , Dieta para Diabéticos/etnologia , Dieta Saudável/etnologia , Feminino , Flavonoides/análise , Frutas/química , Glicosídeos/administração & dosagem , Glicosídeos/análise , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Valor Nutritivo , Cooperação do Paciente/etnologia , Fenóis/análise , Polifenóis/administração & dosagem , Polifenóis/análise
3.
J Endocrinol Invest ; 40(12): 1355-1363, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28646475

RESUMO

PURPOSE: Papillary thyroid carcinoma (PTC), the most common thyroid cancer histotype, has a good prognosis even when spread to the neck lymph node (LN). The prognostic role of LN metastases' location is still controversial. The aim of the present study was to evaluate the clinical relevance of the number and location of LN metastases at presentation in PTCs. METHODS: This retrospective study included a consecutive series of 1653 PTC patients followed for a mean period of 5.9 years in a referral thyroid cancer clinic. All patients have undergone thyroidectomy with the dissection of at least six LNs. According to the LN status, patients were subdivided into 569 N0 (34.4%), 644 N1a (39.0%, central compartment) and 440 N1b (26.6%, latero-cervical compartment). RESULTS: Age at diagnosis was significantly lower in N1b (39.8, IQR 30.7-51.6) and N1a (40.1, IQR 31.3-50.1) than in N0 (44.7, IQR 36.6-55.0 yrs). The male gender was more prevalent in N1b than in N1a and N0 (F/M = 1.9/1, 4.0/1 and 5.5/1, respectively). Persistent/recurrent disease at last control was significantly more frequent in N1b (29.8%) than in N1a (14.3%), and in N1a than in N0 (4.2%) (p < 0.01 for all). Also, distant metastases were significantly (p < 0.001) more frequent in N1b (14.1%) than in N1a (4.3%) and N0 (1.6%). LN metastases' number (>5) was a significant risk factor for persistent/recurrent disease only for N1a patients. CONCLUSIONS: These data indicate that persistent/recurrent disease and distant metastases are significantly more frequent in patients with latero-cervical LN (N1b) metastases and that the LN location should be used for a better postsurgical risk stratification.


Assuntos
Carcinoma Papilar/secundário , Linfonodos/patologia , Neoplasias da Glândula Tireoide/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Papilar/cirurgia , Criança , Feminino , Seguimentos , Humanos , Linfonodos/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Neoplasias da Glândula Tireoide/cirurgia , Adulto Jovem
4.
J Endocrinol Invest ; 39(11): 1315-1321, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27312861

RESUMO

PURPOSE: We recently reported that a high BMI and high waist circumference prevalence is present in Sicilian children and that the male gender is associated with a significant risk of obesity. Early-life and parent-related risk factors were investigated 1521 Sicilian children (752 females and 769 males, aged 9.0-14.0 years) to identify biological and environmental factors that can contribute to obesity onset. METHODS: Anthropometric measurements of children, their urban vs rural area provenience, birth weight and neonatal feeding were collected. In addition, the BMI and educational level of their parents and the perception of their child weight status were investigated. RESULTS: In the study cohort, the prevalence of overweight and obesity was 27.2 and 14.1 %, respectively, significantly (p < 0.05) higher in males than in females. Breastfeeding emerged as a protective factor (OR 0.64; p < 0.0005), while risk factors for developing childhood obesity were a birth weight ≥4.0 kg (OR 1.83; p < 0.05), an overweight or obese mother (OR 2.33; p < 0.0001) or father (OR 1.68; p < 0.0001) and a mother with a low/medium education level (OR 1.72; p < 0.005). CONCLUSION: Understanding risk factors for pediatric obesity is a prerequisite to identify children at highly risk of being obese and to predispose early intervention strategies.


Assuntos
Peso ao Nascer , Meio Ambiente , Transtornos de Alimentação na Infância/fisiopatologia , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Adolescente , Criança , Estudos Transversais , Feminino , Humanos , Itália/epidemiologia , Masculino , Prevalência , Fatores de Risco , Inquéritos e Questionários
5.
J Endocrinol Invest ; 39(7): 779-84, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26928404

RESUMO

PURPOSE: Autoimmune polyendocrine syndromes (APS) type III are characterized by the association of autoimmune thyroid disease (ATD) with other autoimmune diseases such as diabetes, alopecia, pernicious anemia, vitiligo and chronic atrophic gastritis. A strong association between ATD and atrophic gastritis (AG) has been demonstrated. Moreover 10 % of patients affected by AG have a predisposition to develop gastric carcinoid and adenocarcinoma as a result of chronic hypergastrinemia caused by achlorhydria and subsequent ELC cells neoplastic transformation. METHODS: The aim of the study is to evaluate, in a consecutive series of patients followed for ATD in our outpatients clinic, the prevalence of AG. In the period 2004-2014, 242 patients with ATD underwent a screening performing APCA, Vitamin B12, ferritin, iron, and hemoglobin and red cells count measurements with subsequent gastroscopy in case of APCA positivity. RESULTS: We found 57/242 (23.5 %) patients with APCA positivity. Of these patients 33/57 (57.8 %), 31 F and 2 M, were affected by Graves disease; 24/57 (42.1 %) 21 F and 3 M by Hashimoto thyroiditis; 10/57 (17.5 %) presented with anemia, 14/57 (24.5 %) with vitamin B12 deficiency, 9/57 (15.7 %) with iron deficiency. In 2/57 a gastric carcinoid was found. CONCLUSIONS: Our data confirm the high association rate of AG in ATD which frequently is not an isolated disease but configure the picture of APS type III and need to be followed accordingly. An early diagnosis may be useful for diagnosis of gastric carcinoids and to explain and treat a gastric related L-thyroxine malabsorption and presence of chronic unexplained anemia.


Assuntos
Doenças Autoimunes/complicações , Tumor Carcinoide/etiologia , Gastrite Atrófica/etiologia , Neoplasias Gástricas/etiologia , Doenças da Glândula Tireoide/complicações , Adolescente , Adulto , Idoso , Doenças Autoimunes/patologia , Tumor Carcinoide/diagnóstico , Criança , Doença Crônica , Feminino , Gastrite Atrófica/diagnóstico , Gastroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico , Doenças da Glândula Tireoide/patologia , Adulto Jovem
6.
Eur J Nutr ; 55(4): 1645-51, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26303195

RESUMO

PURPOSE: The optimal macronutrient composition of the diet for the management of type 2 diabetes is debated, particularly with regard to the ideal proportion of fat and carbohydrates. The aim of the study was to explore the association of different proportions of fat and carbohydrates of the diet-within the ranges recommended by different guidelines-with metabolic risk factors. METHODS: We studied 1785 people with type 2 diabetes, aged 50-75, enrolled in the TOSCA.IT Study. Dietary habits were assessed using a validated food-frequency questionnaire (EPIC). Anthropometry, fasting lipids, HbA1c and C-reactive protein (CRP) were measured. RESULTS: Increasing fat intake from <25 to ≥35 % is associated with a significant increase in LDL-cholesterol, triglycerides, HbA1c and CRP (p < 0.05). Increasing carbohydrates intake from <45 to ≥60 % is associated with significantly lower triglycerides, HbA1c and CRP (p < 0.05). A fiber intake ≥15 g/1000 kcal is associated with a better plasma lipids profile and lower HbA1c and CRP than lower fiber consumption. A consumption of added sugars of ≥10 % of the energy intake is associated with a more adverse plasma lipids profile and higher CRP than lower intake. CONCLUSIONS: In people with type 2 diabetes, variations in the proportion of fat and carbohydrates of the diet, within the relatively narrow ranges recommended by different nutritional guidelines, significantly impact on the metabolic profile and markers of low-grade inflammation. The data support the potential for reducing the intake of fat and added sugars, preferring complex, slowly absorbable, carbohydrates.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Inflamação/sangue , Idoso , Proteína C-Reativa/metabolismo , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Fibras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários , Triglicerídeos/sangue
7.
Nutr Metab Cardiovasc Dis ; 25(5): 452-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25746910

RESUMO

BACKGROUND AND AIMS: Due to the worldwide increasing prevalence of diabetes (DM), patients with both diabetes and Graves' disease (GD) have become more frequent. Sporadic reports indicate that Graves' orbitopathy (GO), a GD complication that affects orbital soft tissues, can be severe in DM patients. The relationship between these diseases is not well understood. This study aims at evaluating the association of GD and GO with autoimmune and non-autoimmune diabetes (DM) and to assess diabetic features that influence GD and GO prevalence and severity. METHODS AND RESULTS: This retrospective study evaluated GD, GO and DM association in 1211 consecutive GD patients (447 with GO and 77 with DM). A case-control study was carried out to evaluate DM relationship with GO severity by comparing at 1:2 ratio GO patients with or without DM. A strong association was found between GD and T1DM (p = 0.01) but not T2DM. Instead, the presence of GO was strongly associated with T2DM (p = 0.01). Moreover, GO was more frequently severe in GD patients with T2DM (11/30 or 36.6%) than in those without T2DM (1/60 or 1.7%, p = 0.05). T2DM was the strongest risk factor for severe GO (OR = 34.1 vs. 4.4 p < 0.049 in cigarette smokers). DM duration, obesity and vascular complications, but not metabolic control were significant determinants of GO severity. CONCLUSIONS: GD is associated with T1DM but not with T2DM, probably because of the common autoimmune background. GO, in contrast, is more frequent and severe in T2DM, significantly associated with obesity, diabetes duration and diabetic vasculopathy but not metabolic control.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Doença de Graves/complicações , Oftalmopatia de Graves/etiologia , Adulto , Índice de Massa Corporal , Estudos de Casos e Controles , Estudos de Coortes , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Angiopatias Diabéticas/complicações , Feminino , Doença de Graves/fisiopatologia , Oftalmopatia de Graves/epidemiologia , Oftalmopatia de Graves/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Obesidade/fisiopatologia , Sobrepeso/complicações , Sobrepeso/fisiopatologia , Prevalência , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Sicília/epidemiologia
8.
Nutr Metab Cardiovasc Dis ; 23(9): 808-15, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23932729

RESUMO

Cancer incidence and mortality are higher among diabetic patients. This review examines the mechanisms, both general and site-specific, for this increase. Hyperglycemia and hyperinsulinemia, which are the major abnormalities that characterize diabetes, can promote cancer via both independent and synergic mechanisms. Insulin is both a metabolic hormone and a growth factor that promotes cell proliferation. When insulin levels are increased due to either insulin resistance or insulin treatment, their mitogenic effect is more marked in malignant cells that frequently overexpress the insulin receptor and, more specifically, its A isoform that has predominant mitogenic activity. Hyperglycemia provides energy for malignant cell proliferation and, via the peculiar energy utilization of cancer cells, favors cancer growth and neoangiogenesis. Additionally, diabetes-associated obesity has cancer-promoting effects due to mechanisms that are specific to excess fat cells (such as increased peripheral estrogens, increased pro-mitogen cytokines and growth factors). Also fat-associated chronic inflammation can favor cancer via the cell damage caused by reactive oxygen species (ROS) and via the production of inflammatory cytokines and transcription factors that stimulate cancer growth and invasiveness. Finally, the multiple drugs involved in the treatment of diabetes can also play a role. Diabetes-associated comorbidities, tissue-specific inflammation, and organ-specific dysfunctions can explain why the risk of cancer can differ by tissue type among diabetic patients. The increased risk of cancer-related mortality is moderate among individual patients with diabetes (RR = 1.25), but the pandemic nature of the disease means that a considerable number of lives could be spared through a better understanding of the factors associating diabetes and cancer.


Assuntos
Neoplasias da Mama/fisiopatologia , Neoplasias Colorretais/fisiopatologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Neoplasias do Endométrio/fisiopatologia , Neoplasias Hepáticas/fisiopatologia , Neoplasias da Próstata/fisiopatologia , Neoplasias da Mama/etiologia , Neoplasias Colorretais/etiologia , Citocinas/sangue , Diabetes Mellitus Tipo 2/complicações , Neoplasias do Endométrio/etiologia , Feminino , Humanos , Hiperglicemia/complicações , Hiperglicemia/tratamento farmacológico , Hiperinsulinismo/complicações , Hiperinsulinismo/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Inflamação/complicações , Inflamação/tratamento farmacológico , Insulina/sangue , Insulina/uso terapêutico , Resistência à Insulina , Neoplasias Hepáticas/etiologia , Masculino , Obesidade/complicações , Obesidade/tratamento farmacológico , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Neoplasias da Próstata/etiologia , Fatores de Risco
9.
J Endocrinol Invest ; 36(10): 843-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23656720

RESUMO

BACKGROUND: Fine needle cytology aspirates (FNA) classified as THY4 are a heterogeneous group suspicious for malignancy [papillary thyroid cancer (PTC)], which is confirmed in 50-80% of cases after surgery. AIM: To better stratify THY4 FNA specimens for the relative risk of malignancy. METHODS: We retrospectively analyzed 78 thyroid nodules classified as THY4 because of the presence of atypical cells, hypercellular trabeculae and/or intranuclear inclusions (ICI), in the absence of papillae. Two subgroups were identified: group 1 (38 nodules), showing ICI with (no.=17) or without (no.=21) trabeculae and cellular atypia, and group 2 (40 nodules), showing trabeculae and atypia but without ICI. RESULTS: PTC was detected at histology in 56/78 of the patients (71.8%). Malignancy occurred in 36/38 (94.7%) of the patients in group 1 and in 20/40 (50.0%) of the patients in group 2. Therefore, the positive predictive value (PPV) for PTC was 97.3% in the ICI+ specimens (group 1), with a sensitivity of 64.3% and specificity of 95.2%. When only ICI was present, without atypia and trabeculae, the PPV and specificity were similar (95.0 and 95.2%, respectively), but the sensitivity was decreased (48.7%). In specimens without ICI (group 2), the PPV was only 50.0%; however, combined with young age (<40 yr) and male gender, it reached a value similar to that of group1. CONCLUSIONS: In ICI+ specimens compared to ICI-, the risk of PTC is nearly doubled, since PPV increases from 50.0% to 97.3%. This observation suggests that surgery should be considered mandatory in all lesions classified THY4 at FNA, although the relevant difference in terms of cancer risk between ICI- vs ICI+ nodules might be an useful information for both the clinician and the patient.


Assuntos
Carcinoma Papilar/diagnóstico , Citodiagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/patologia , Adulto , Idoso , Biópsia por Agulha Fina , Carcinoma Papilar/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/cirurgia , Tireoidectomia
10.
Nutr Metab Cardiovasc Dis ; 22(11): 997-1006, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23063367

RESUMO

BACKGROUND AND AIMS: Metformin is the first-line therapy in type 2 diabetes. In patients inadequately controlled with metformin, the addition of a sulfonylurea or pioglitazone are equally plausible options to improve glycemic control. However, these drugs have profound differences in their mechanism of action, side effects, and impact on cardiovascular risk factors. A formal comparison of these two therapies in terms of cardiovascular morbidity and mortality is lacking. The TOSCA.IT study was designed to explore the effects of adding pioglitazone or a sulfonylurea on cardiovascular events in type 2 diabetic patients inadequately controlled with metformin. METHODS: Multicentre, randomized, open label, parallel group trial of 48 month duration. Type 2 diabetic subjects, 50-75 years, BMI 20-45 Kg/m(2), on secondary failure to metformin monotherapy will be randomized to add-on a sulfonylurea or pioglitazone. The primary efficacy outcome is a composite endpoint of all-cause mortality, nonfatal myocardial infarction, nonfatal stroke, and unplanned coronary revascularization. Principal secondary outcome is a composite ischemic endpoint of sudden death, fatal and non-fatal myocardial infarction and stroke, endovascular or surgical intervention on the coronary, leg or carotid arteries, major amputations. Side effects, quality of life and economic costs will also be evaluated. Efficacy, safety, tolerability, and study conduct will be monitored by an independent Data Safety Monitoring Board. End points will be adjudicated by an independent external committee. CONCLUSIONS: TOSCA.IT is the first on-going study investigating the head-to-head comparison of adding a sulfonylurea or pioglitazone to existing metformin treatment in terms of hard cardiovascular outcomes. REGISTRATION: Clinicaltrials.gov ID NCT00700856.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Compostos de Sulfonilureia/uso terapêutico , Tiazolidinedionas/uso terapêutico , Idoso , Glicemia/análise , Índice de Massa Corporal , Doenças Cardiovasculares/induzido quimicamente , Quimioterapia Combinada , Determinação de Ponto Final , Feminino , Seguimentos , Humanos , Masculino , Metformina/uso terapêutico , Pessoa de Meia-Idade , Pioglitazona , Qualidade de Vida , Fatores de Risco , Compostos de Sulfonilureia/efeitos adversos , Inquéritos e Questionários , Tiazolidinedionas/efeitos adversos , Resultado do Tratamento
11.
Neuroscience ; 194: 136-49, 2011 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-21824508

RESUMO

The cortical representation of heading perception derives from several functional processes distributed across many cortical areas. The aim of the present study was to assess if the optic flow motion directions, expansion and contraction, differently modulate the firing activity of area PEc neurons. We determined the influence of the eye position and/or the spatial position of the focus of expansion (FOE) on this activity. Single neuron activity during radial optic flow stimulation was recorded in three behaving monkeys. The retinal FOE position and the spatial eye position were examined in order to study eye position's influence upon the directional selectivity for the radial stimuli. We observed that the neurons able to discriminate the retinotopic FOE position are differently modulated by expansion and contraction. One class of neurons exhibited a different preferred FOE position during expansion and contraction. A second class showed the same preferred position with similar firing activity in the two stimuli. A third class showed the same preferred position but different firing activity. Eye position affected the directional selectivity of most PEc cells. The main result of this study is that there is a continuum in cell modulation by optic flow direction, and it can be modified by the angle of gaze with respect to the FOE. These results shed light on potential cellular integrative mechanisms of area PEc in heading perception.


Assuntos
Percepção de Movimento/fisiologia , Fluxo Óptico/fisiologia , Lobo Parietal/fisiologia , Células Receptoras Sensoriais/fisiologia , Percepção Espacial/fisiologia , Potenciais de Ação/fisiologia , Animais , Comportamento Animal/fisiologia , Movimentos Oculares/fisiologia , Macaca fascicularis , Masculino , Lobo Parietal/anatomia & histologia , Córtex Visual/anatomia & histologia , Córtex Visual/fisiologia , Vias Visuais/anatomia & histologia , Vias Visuais/fisiologia
12.
Neuroscience ; 171(4): 1241-55, 2010 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-20870015

RESUMO

The visual perception of self-motion is mainly provided by optic flow. Eyes usually scan the environment during locomotion, and the gaze is not always directed to the focus of expansion (FOE) of the flow field. Such eye movements change the retinal FOE position with respect to the fovea. Here, we assess if optic flow selective neurons in parietal area PEc are modulated by eye position. We recorded single neuron activity during radial optic flow stimulation in two monkeys, varying eye and retinal FOE positions. We found that the majority of PEc neurons are modulated by the FOE retinotopic position with different tuning for expansion and contraction. Although many neurons did not show any gaze field without visual stimulation, the eye position modulated optic flow responses in about half of the cells. These novel results suggest that PEc neurons integrate both visual and eye position signals, and allow us to hypothesize their role in guiding locomotion as a part of a cortical network involved in FOE representation during self-motion. Visual and eye position interaction in this area could be seen as a contribution to the building of the invariant space representation necessary to motor planning.


Assuntos
Fluxo Óptico/fisiologia , Células Receptoras Sensoriais/fisiologia , Córtex Visual/fisiologia , Vias Visuais/fisiologia , Análise de Variância , Animais , Movimentos Oculares/fisiologia , Lateralidade Funcional , Macaca fascicularis , Masculino , Estimulação Luminosa/métodos , Psicofísica , Tempo de Reação , Córtex Visual/citologia , Campos Visuais/fisiologia
13.
Acta Diabetol ; 47(4): 271-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20730455

RESUMO

Insulin analogs are artificially modified insulin molecules that allow better metabolic controls of diabetes through either more rapid or more prolonged activity. The interaction of insulin analogs with the insulin receptor isoforms (IR-A and IR-B) and with the IGF-I receptor (IGF-IR) is similar but not identical to that of insulin, and therefore, their biological effects do not always reproduce insulin actions in terms of quantity, quality and timing. Studies on in vitro models indicate that short-acting analogs elicit molecular and biological effects that are similar, but not identical, to those of insulin via IR-A, IR-B and IGF-IR. In contrast, long-acting analogs behave in a more different way relative to insulin. Although data are not homogeneous and observations on the more recently introduced detemir are scarce, both glargine and detemir often show a decreased binding to IR and increased binding to IGF-IR. Also, intracellular signaling is different with respect to insulin, with a prevalent activation of the ERK rather than the AKT pathway. Finally, an increased mitogenic response has often been observed with these analogs in a variety of cell models. Of course, in vitro studies do not necessarily reflect what occurs in patients, due to the different metabolism of analogs in vivo and their interaction with components of the extracellular environment. After many years of analog's use, observations in patients indicate that insulin analogs are both effective and safe. Prospective clinical studies, however, may add further useful information on the issue of the insulin analogs' possible differences with respect to native insulin.


Assuntos
Hipoglicemiantes/farmacologia , Insulina/análogos & derivados , Insulina/farmacologia , Receptor IGF Tipo 1/fisiologia , Receptor de Insulina/fisiologia , Animais , Humanos , Hipoglicemiantes/metabolismo , Insulina/metabolismo , Ligação Proteica/fisiologia , Receptor IGF Tipo 1/agonistas , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/agonistas , Receptor de Insulina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
14.
Diabetologia ; 53(8): 1743-53, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20424816

RESUMO

AIMS/HYPOTHESIS: Five insulin analogues, with modified insulin-like molecular structures, are currently approved for treating diabetic patients. They activate cell signalling and biological responses via insulin receptor isoforms (IR-A and IR-B), each having specific characteristics for eliciting cell responses. The molecular and biological effects of these analogues on receptor isoforms in comparison to native insulin are not well defined, and their effects on the IGF1 receptor (IGF1R) are controversial. The characterisation of these effects was the aim of the present study. METHODS: Short-acting (insulin lispro [B28Lys,B29Pro human insulin], insulin aspart [B28Asp human insulin], insulin glulisine [B3Lys,B29Glu human insulin]) and long-acting (insulin glargine [A21Gly,B31Arg,B32Arg human insulin], insulin detemir [B29Lys(epsilon-tetradecanoyl),desB30 human insulin]) insulin analogues were studied in three engineered cell models (R(-), IGF1R-deprived mouse fibroblasts transfected with either only human IR-A or IR-B or IGF1R). Receptor binding and phosphorylation, AKT and extracellular signal-regulated kinase (ERK) activation, cell proliferation and colony formation were evaluated after exposing the cells to each analogue and were compared with insulin, IGF1 and the carcinogenic analogue B10Asp. RESULTS: All short-acting insulin analogues produced molecular and biological effects similar but not identical to those of insulin. Relative to insulin, long-acting analogues more strongly activated the ERK pathway via both IR-A and IGF1R as well as increased cell proliferation. At the concentration tested, no analogue (except B10Asp via IR-A) had increased transforming activity. CONCLUSIONS/INTERPRETATION: Cell models that permit comparisons of the activity of insulin to that of insulin analogues via each receptor individually indicate that only minor differences exist between insulin and short-acting analogues. By contrast, long-acting analogues activate the mitogenic signalling pathway more effectively than insulin and cause increased cell proliferation.


Assuntos
Proliferação de Células/efeitos dos fármacos , Insulina/análogos & derivados , Insulina/farmacologia , Receptor de Insulina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Análise de Variância , Animais , Western Blotting , Células Cultivadas , Humanos , Insulina/metabolismo , Camundongos , Fosforilação/efeitos dos fármacos
16.
J Sports Med Phys Fitness ; 50(1): 99-108, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20308980

RESUMO

AIM: Visual search strategy in sports may influence performance. Thus it is interesting to investigate oculo-motor behavior of athletes and its possible impingement upon sport training and coaching. The differences in fixations and saccadic eye movements between expert volleyball players and novice subjects was studied, by carrying out a precise analysis of gaze shifts during the observation of a standard game situation. METHODS: Fifteen professional athletes and fifteen non athletes watched at a volleyball filmed sequence in which a setter receives a pass tossed from the coach and sets it forward or backward. Then, the number and duration of fixations to specific interest areas (IAs) were counted. In addition, the sequences of saccades from each IA to the others were analyzed. RESULTS: The results showed that expert players performed fewer fixations of longer duration and spent more time looking first at the initial pass trajectory and then at the setter's hands, disregarding the ball trajectory. The non athletes, instead, followed the whole course of the ball, before and after the hands touch. CONCLUSION: These findings support the interpretation that experts volleyball players extract more task-relevant information from each fixation than do less skilled athletes, and that player's proficiency influences the strategy used in the treatment of visual information.


Assuntos
Atenção/fisiologia , Olho , Fenômenos Fisiológicos Oculares , Movimentos Sacádicos/fisiologia , Voleibol/fisiologia , Adulto , Análise de Variância , Estudos de Casos e Controles , Humanos , Masculino , Análise Multivariada , Músculos Oculomotores/fisiologia , Gravação em Vídeo
17.
Nutr Metab Cardiovasc Dis ; 19(1): 45-53, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18450436

RESUMO

BACKGROUND AND AIM: The aim of the present study was to assess health-related quality of life (HRQOL) and treatment satisfaction in a large, ambulatory based sample of patients with type 2 diabetes. In particular, we evaluated a large array of socio-economic, clinical, and management-related factors, to investigate the extent to which they correlate with physical and psychological well-being, and with treatment satisfaction. METHODS AND RESULTS: Patients were requested to fill in a questionnaire including the SF-36 Health Survey (SF-36), the WHO-Well Being Questionnaire (WBQ), and the WHO-Diabetes Treatment Satisfaction Questionnaire (DTSQ). The analyses were based on multivariate analyses, adjusted for patient clinical and socio-demographic characteristics. The study involved 2499 patients, enrolled in 203 diabetes outpatient clinics. Female gender and diabetes complications were associated with worse physical and psychological well-being, while socioeconomic variables were mainly related to general well-being. The perceived frequency of hyperglycemic episodes was negatively associated with all the dimensions explored. Treatment satisfaction was inversely related to female gender, insulin treatment, perceived frequency of hyperglycemic episodes and diabetes complications. Blood glucose self-monitoring, and among patients treated with insulin, self-management of insulin doses and the use of pen for insulin injections, were associated with higher levels of satisfaction. Finally, higher levels of satisfaction were associated with a better perception of physical and psychological well-being. CONCLUSIONS: Health related quality of life and treatment satisfaction are associated with each other and are both affected by a complex interplay between clinical and socio-economic variables. Some negative aspects, mainly associated with insulin treatment and poor perceived metabolic control, can be attenuated by a deeper involvement of the patients in the management of the disease.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Satisfação do Paciente , Qualidade de Vida , Fatores Socioeconômicos , Idoso , Índice de Massa Corporal , Complicações do Diabetes/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Feminino , Nível de Saúde , Humanos , Hiperglicemia/epidemiologia , Hipoglicemia/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Inquéritos e Questionários , Organização Mundial da Saúde
18.
Neuroscience ; 156(3): 413-24, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-18782605

RESUMO

Neurons in area PEc in the superior parietal cortex encode signals from different modalities, such as visual, extraretinal and somatosensory, probably combining them to encode spatial parameter of extrapersonal space to prepare body movements. This study reports the characterization of the functional properties of PEc non-visual neurons that showed saccade-related activity. We analyzed the pre- and post-saccadic firing activity in 189 neurons recorded in five hemispheres of three behaving monkeys. Spiking activity of PEc single neurons was recorded while the monkeys performed visually-guided saccades in a reaction time task. We found that 84% of neurons recorded from area PEc showed pre-saccadic activity with directional tuning. In 26% of neurons, we found inhibition of activity in the pre-saccadic period. The onset of this "pause" always started before the saccade and, in 51% of neurons, it was invariant among different gaze directions. The post-saccadic activity in these cells was either a phasic response with directional tuning (77%) and/or an eye position tuning (75%). The analysis of the preferred direction did not show hemispheric preference, however, for the majority of neurons, the angular difference in the preferred direction, in the pre- and post-saccadic period, was more than 60 degrees . By confirming, therefore, that PEc neurons carry information about eye position, these novel findings open new horizons on PEc function that, to date, is not well documented. The pre-saccadic activity may reflect an involvement in saccade control, whereas post-saccadic activity may indicate a role in informing on the new eye position. These novel results about saccade and eye position processing may imply a role of area PEc in gaze direction mechanisms and, possibly, in remapping visual space after eye movements.


Assuntos
Potenciais de Ação/fisiologia , Fixação Ocular/fisiologia , Neurônios/fisiologia , Lobo Parietal/citologia , Movimentos Sacádicos/fisiologia , Animais , Comportamento Animal , Distribuição de Qui-Quadrado , Lateralidade Funcional/fisiologia , Macaca fascicularis , Masculino , Inibição Neural/fisiologia , Orientação/fisiologia , Tempo de Reação/fisiologia , Campos Visuais/fisiologia , Percepção Visual/fisiologia
19.
J Endocrinol Invest ; 30(3): 259-62, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17505163

RESUMO

Necrobiosis lipoidica (NL) is a degenerative disease of dermal connective tissue of unknown etiology characterized by erythematous plaques preferentially localized to distal extremities. Skin lesions show a chronic relapsing nature. NL is often associated with diabetes mellitus and satisfactory treatment options are lacking. We describe the spontaneous healing of NL lesions after pancreas and kidney transplantation in a Type 1 diabetic patient with chronic NL recalcitrant to a variety of standard treatments. The 31-yr-old male patient had experienced NL lesions for more than 15 yr; despite various systemic and topical treatments, the skin lesions had pregressively enlarged. Because of end-stage renal disease, a simultaneous pancreas and kidney transplantation was performed and immunosuppressive therapy with tacrolimus (TAC), mycophenolate mofetil (MMF), and prednisone was started. Pancreatic transplantation maintained satisfactory metabolic control with no need of exogenous insulin. After transplantation, skin lesions slowly healed without any specific treatment, leaving residual areas of fibrotic scars. A skin biopsy confirmed the absence of typical NL lymphocytic and histiocytic inflammatory response. Clinical remission of NL lesions may probably be explained by the concomitant effect of multiple-drug regimen for immunosuppression (TAC, MMF, and prednisone) and improved skin microcirculation secondary to the good metabolic control provided by pancreas transplantation.


Assuntos
Diabetes Mellitus Tipo 1/cirurgia , Transplante de Rim , Necrobiose Lipoídica/cirurgia , Transplante de Pâncreas , Cicatrização , Adulto , Doença Crônica , Diabetes Mellitus Tipo 1/patologia , Humanos , Masculino , Necrobiose Lipoídica/patologia
20.
Diabet Med ; 22(5): 606-11, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15842516

RESUMO

AIMS: This randomized, multi-centre, double-blind, stratified, two period, cross-over trial was undertaken to assess the pharmacokinetics and pharmacodynamics of insulin aspart injected immediately before compared with regular human insulin injected 30 min before a Mediterranean-style meal in 37 (23 M, 14 F) patients with Type 2 diabetes. METHODS: Insulin aspart or regular human insulin was given subcutaneously (0.15 U/kg) in random sequence, using a double-dummy technique (at one visit: human regular insulin at t=-30 min and placebo at t=0; at the other visit: placebo at t=-30 min and aspart insulin at t=0). Serum glucose and insulin concentrations (15 points) were measured after each meal for 240 min. RESULTS: Post-prandial glycaemic excursions were 20% lower with insulin aspart (IAsp) compared with regular human insulin (HI) treatment [ratio (Iasp/HI)=0.80, CI=(0.66-0.98), P=0.034]. The maximum serum glucose (SG) concentration was similar for the two treatments (P=NS). The (median) time to maximum SG was 25 min shorter for IAsp compared with HI (P=0.048). Maximum serum insulin concentration was higher after IAsp compared with HI (P=0.023) as well as the area under the 4-h serum insulin curve (P=0.006). Furthermore, the time to maximum serum insulin concentration was 27 min shorter after IAsp (P=0.039), even though IAsp was injected 30 min after HI. No adverse events occurred during the trial. CONCLUSIONS: In patients with Type 2 diabetes a more favourable insulin profile and a better glycaemic control were found with IAsp injected immediately before compared with HI injected 30 min before a Mediterranean-style meal.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina/análogos & derivados , Insulina/uso terapêutico , Idoso , Diabetes Mellitus Tipo 2/sangue , Método Duplo-Cego , Feminino , Humanos , Insulina Aspart , Masculino , Pessoa de Meia-Idade , Período Pós-Prandial/fisiologia , Fatores de Tempo
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