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1.
Artigo em Inglês | MEDLINE | ID: mdl-36673912

RESUMO

There are marked differences in the regional distribution of childhood obesity in Italy. This study sought to investigate the interaction between geographical areas and family environment of dietary habits, physical activity, nutritional knowledge and obesity of adolescents. A cross-sectional study was conducted on 426 school-aged children and 298 parents residing in Central Italy (Florence, Tuscany) and Southern Italy (Corigliano, Calabria), in 2021. Survey questionnaire investigated anthropometry, eating behavior, nutritional knowledge and physical activity. BMI was determined and compared with reference percentile charts for adolescents. Multivariate regression analyses showed that: (1) an adolescent's BMI was directly influenced by their parents' BMI independently of parental nutritional knowledge and dietary or physical activity habits; (2) parents transmitted eating or physical activity habits to their children; (3) the geographic region of residence is not in itself an independent determinant of children's BMI. The clear message is that prevention of childhood obesity should consider family-based approaches. Parental obesity can be the point of convergence of the complex interactions between a parent's and child's habits and should be one of the most important factors to look for.


Assuntos
Obesidade Infantil , Adolescente , Criança , Humanos , Obesidade Infantil/epidemiologia , Estudos Transversais , Comportamento Alimentar , Dieta , Exercício Físico , Inquéritos e Questionários
2.
ACS Appl Mater Interfaces ; 12(16): 18660-18666, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32216304

RESUMO

There is huge research activity in the development of flexible and biocompatible piezoelectric materials for next-generation compliant micro electro-mechanical systems (MEMS) transducers to be exploited in wearable devices and implants. This work reports for the first time on the development of flexible ScxAl(1-x)N films deposited by sputtering technique onto polyimide substrates, assessing their piezoelectricity and biocompatibility. Flexible ScxAl(1-x)N films have been analyzed in terms of morphological, structural, and piezoelectric properties. ScxAl(1-x)N layer exhibits a good surface roughness of 4.40 nm and moderate piezoelectricity with an extracted effective piezoelectric coefficient (d33eff) value of 1.87 ± 0.06 pm/V, in good agreement with the diffraction pattern analysis results. Cell viability assay, performed to study the interaction of the ScxAl(1-x)N films with human cell lines, shows that this material does not have significant effects on tested cells. Furthermore, the ScxAl(1-x)N layer, integrated onto a flexible device and analyzed by bending/unbending measurements, shows a peak-to-peak open-circuit voltage (VOC) of 0.32 V and a short-circuit current (ISC) of 0.27 µA, with a generated power of 19.28 nW under optimal resistive load, thus demonstrating the potential of flexible ScxAl(1-x)N films as active layers for next-generation wearable/implantable piezoelectrics.


Assuntos
Compostos de Alumínio/química , Materiais Biocompatíveis/química , Sistemas Microeletromecânicos , Escândio/química , Transdutores , Materiais Biocompatíveis/toxicidade , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Desenho de Equipamento , Humanos , Nanotecnologia , Maleabilidade , Dispositivos Eletrônicos Vestíveis
3.
Analyst ; 137(22): 5260-4, 2012 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-23012692

RESUMO

The integration of a polycrystalline material such as aluminum nitride (AlN) on a flexible substrate allows the realization of elastic tactile sensors showing both piezoelectricity and significant capacitive variation under normal stress. The application of a normal stress on AlN generates deformation of the flexible substrate on which AlN is grown, which results in strain gradient of the polycrystalline layer. The strain gradient is responsible for an additional polarization described in the literature as the flexoelectric effect, leading to an enhancement of the transduction properties of the material. The flexible AlN is synthesized by sputtering deposition on kapton HN (poly 4,4'-oxydiphenyl pyromellitimide) in a highly oriented crystal structure. High orientation is demonstrated by X-ray diffraction spectra (FWHM = 0.55° of AlN (0002)) and HRTEM. The piezoelectric coefficient d(33) and stress sensitive capacitance are 4.7 ± 0.5 pm V(-1) and 4 × 10(-3) pF kPa(-1), respectively. The parallel plate capacitors realized for tactile sensing present a typical dome shape, very elastic under applied stress and sensitive in the pressure range of interest for robotic applications (10 kPa to 1 MPa). The flexibility of the device finalized for tactile applications is assessed by measuring the sensor capacitance before and after shaping the sensing foil on curved surfaces for 1 hour. Bending does not affect sensor's operation, which exhibits an electrical Q factor as high as 210, regardless of the bending, and a maximum capacitance shift of 0.02%.


Assuntos
Compostos de Alumínio/química , Tato , Capacitância Elétrica , Imidas/química , Pressão , Semicondutores , Difração de Raios X
4.
J Clin Gastroenterol ; 40(9): 833-41, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17016141

RESUMO

Acute alcoholic hepatitis (AAH) is a frequent inflammatory liver disease with high short-term mortality rate. In this review, relationships between alcohol abuse and the epidemiology and the outcomes of AAH are discussed, as well as AAH pathogenesis. The role of endotoxins, tumor necrosis factor alpha, fibroblasts, and immune response to altered hepatocyte proteins is discussed. The need of a careful prognosis, supported by the use of Maddrey score, by the model for end-stage liver disease [Mayo end-stage liver disease (MELD)] score or by the Glasgow alcoholic hepatitis score, is outlined, as the use of the most effective drugs (glucocorticoids and anti-tumor necrosis factor alpha infliximab) is recommended only in severe AAH cases. The problems of liver transplant in severe AAH, and the need of a 6-month alcohol abstinence before transplant, are discussed, as well as the need of a careful psychologic assessment before the transplant.


Assuntos
Hepatite Alcoólica , Doença Aguda , Animais , Etanol/metabolismo , Hepatite Alcoólica/diagnóstico , Hepatite Alcoólica/patologia , Hepatite Alcoólica/fisiopatologia , Hepatite Alcoólica/terapia , Hepatócitos/química , Síndrome Hepatorrenal/etiologia , Humanos , Lipopolissacarídeos , Transplante de Fígado , Prognóstico , Fator de Necrose Tumoral alfa/fisiologia
5.
Neurosci Lett ; 377(3): 195-9, 2005 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-15755525

RESUMO

This preliminary study describes magnetic resonance imaging (MRI) data on the effects of sub-chronic nicotine administration in rats. Nicotine 0.4 mg/kg s.c. free base was given once a day for 4 days to Wistar adult male rats. On day 5, anaesthetized subjects were observed using an MRI tomography system. Regional cerebral blood volume (rCBV) and transversal relaxation time (T2) MRI parameters were measured. Nicotine treatment increased T2 values, with a significant effect in the cingulate cortex. A trend to increase was also observed in the prefrontal cortex and nucleus accumbens. Similarly, the effect of nicotine on rCBV was a significant increase in values compared to saline treatment. Post hoc analysis showed a significant effect of nicotine in the prefrontal cortex, cingulate cortex, mediodorsal thalamus and lateral posterior thalamus. This study showed for the first time that sub-chronic nicotine administration can induce changes in MRI pattern which are (i) similar to human MRI studies, and (ii) common to those described for markers of neuronal metabolic activation in corticolimbic brain regions known to be involved in nicotine dependence.


Assuntos
Volume Sanguíneo/efeitos dos fármacos , Circulação Cerebrovascular/efeitos dos fármacos , Imageamento por Ressonância Magnética/métodos , Nicotina/administração & dosagem , Vasodilatação/efeitos dos fármacos , Animais , Volume Sanguíneo/fisiologia , Circulação Cerebrovascular/fisiologia , Masculino , Ratos , Ratos Wistar , Fatores de Tempo , Vasodilatação/fisiologia
6.
J Cell Physiol ; 195(3): 402-10, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12704649

RESUMO

Angiotensin-II (AII), the dominant effector of the renin-angiotensin system, is involved in the pathogenesis of cardiovascular diseases, such as atherosclerosis. Upregulation of the adhesion molecules VCAM-1, ICAM-1, and E-selectin in endothelial cells by inflammatory cytokines through nuclear factor kappa B (NFkappaB) activation is implicated in formation and progression of atherosclerotic plaque. Here we show that AII induces NFkappaB-dependent transcription in primary endothelial cell lines, leading to the upregulation of ICAM-1 and VCAM-1 expression. NFkappaB activation by AII is mediated by the NFkappaB-inducing kinase (NIK), a common mediator of NFkappaB activation by inflammatory cytokines, such as TNF-alpha. However, NFkappaB stimulation by AII differs from that of TNF-alpha since a TNF-receptor associated factor 2 (TRAF-2) dominant negative mutant does not prevent AII-mediated NFkappaB activation. In analogy with TNF-alpha-dependent activation of NFkappaB, treatment with either the anti-oxidant N-acetyl cysteine (NAC) or the cyclooxygenase (COX) inhibitor acetyl salicylic acid (aspirin), but not indometacin, prevents the induction of NFkappaB-dependent transcription by AII. Thus, production of reactive oxygen species, aspirin (asp)-sensitive enzymes of the arachidonate metabolism, and NIK are common transducers of AII- and TNF-dependent pathways to NFkappaB. AII also activates the inflammatory p38 kinase in endothelial cells, an effect inhibited by exposure to either NAC or asp. Pharmacological interference of the p38 pathway, with the inhibitor SB 202190, prevented AII-mediated activation of the NFkappaB target V-CAM, without affecting degradation of IkappaBalpha. These results support a pro-inflammatory effect of the vasoactive peptide AII in endothelial cells, through at least two pathways-NFkappaB and p38-both of which are sensitive to asp and antioxidants.


Assuntos
Angiotensina II/farmacologia , Endotélio Vascular/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Angiotensina II/antagonistas & inibidores , Aspirina/farmacologia , Células Cultivadas , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/enzimologia , Humanos , Molécula 1 de Adesão Intercelular/biossíntese , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Fator 2 Associado a Receptor de TNF , Ativação Transcricional , Fator de Necrose Tumoral alfa/farmacologia , Molécula 1 de Adesão de Célula Vascular/biossíntese , Proteínas Quinases p38 Ativadas por Mitógeno , Quinase Induzida por NF-kappaB
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