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1.
Neuroimage ; 263: 119672, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36209795

RESUMO

Language processing is a highly integrative function, intertwining linguistic operations (processing the language code intentionally used for communication) and extra-linguistic processes (e.g., attention monitoring, predictive inference, long-term memory). This synergetic cognitive architecture requires a distributed and specialized neural substrate. Brain systems have mainly been examined at rest. However, task-related functional connectivity provides additional and valuable information about how information is processed when various cognitive states are involved. We gathered thirteen language fMRI tasks in a unique database of one hundred and fifty neurotypical adults (InLang [Interactive networks of Language] database), providing the opportunity to assess language features across a wide range of linguistic processes. Using this database, we applied network theory as a computational tool to model the task-related functional connectome of language (LANG atlas). The organization of this data-driven neurocognitive atlas of language was examined at multiple levels, uncovering its major components (or crucial subnetworks), and its anatomical and functional correlates. In addition, we estimated its reconfiguration as a function of linguistic demand (flexibility) or several factors such as age or gender (variability). We observed that several discrete networks could be specifically shaped to promote key functional features of language: coding-decoding (Net1), control-executive (Net2), abstract-knowledge (Net3), and sensorimotor (Net4) functions. The architecture of these systems and the functional connectivity of the pivotal brain regions varied according to the nature of the linguistic process, gender, or age. By accounting for the multifaceted nature of language and modulating factors, this study can contribute to enriching and refining existing neurocognitive models of language. The LANG atlas can also be considered a reference for comparative or clinical studies involving various patients and conditions.


Assuntos
Conectoma , Adulto , Humanos , Encéfalo , Idioma , Atenção , Imageamento por Ressonância Magnética , Rede Nervosa/diagnóstico por imagem
2.
Ann Ig ; 33(6): 564-582, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33443282

RESUMO

Aim: This study aimed to assess if spirituality could be a predictor of organ donation, using a descriptive/knowledge survey aimed at healthcare professionals working in Italy. Methods: This multicentre, descriptive observational study was conducted in three Italian regions (Lombardy, Piedmont and Apulia). Two scales were used for the data collection: the Organ Donation Attitude Scale (ODAS) to explore the healthcare staff's attitudes towards organ donation and the Spiritual Health Life-Orientation Measure (SHALOM) to explore their perception of the concept of spirituality. Results: The sample included 688 healthcare professionals (460 females, 66.9%). The analysis of their attitudes, assessed as their predisposition to organ donation, evidenced the women's higher degree of agreement regarding the safety and effectiveness of the practice (40.7% versus 31.1%, p = 0.001). The sample showed a high positive attitude towards organ donation (M = 4.25, SD = 0.50), whereas the level of spirituality was slightly lower than the midpoint of the Likert scale (M = 2.76, SD = 1.31). Spirituality positively predicted the positive attitude towards organ donation among Lombard professionals with shorter (-1 SD) careers (b = 0.078, p = 0.044) and among both Piedmontese (b = 0.250, p < 0.001) and Apulian (b = 0.458, p < 0.001) professionals with longer (+1 SD) careers. Discussion: Regarding organ donation, the surveyed healthcare professionals showed higher scores in the positive attitude section and lower scores in the negative attitude section, regardless of the geographical context of reference.


Assuntos
Espiritualidade , Obtenção de Tecidos e Órgãos , Atitude do Pessoal de Saúde , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Humanos , Itália , Inquéritos e Questionários
3.
Neuroimage ; 210: 116574, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31981780

RESUMO

The decision to process an incoming stimulus attentively - and to trigger a follow-up cascade of high-level processes - is strategic for the human brain as it becomes transiently unavailable to subsequent stimulus processing. In this study, we set to identify brain networks that carry out such evaluations. We therefore assessed the time-course of neural responses with intracerebral EEG in human patients during an attentional reading task, contrasting to-be-attended vs. to-be-ignored items. We measured High-Frequency Activity [50-150 â€‹Hz] as a proxy of population-level spiking activity and we identified a crucial component of a Gate-Keeping Mechanism bilateral in the mid-Ventro-Lateral Prefrontal Cortex (VLPFC), at the interplay of the Ventral and Dorsal Attention Networks, that selectively reacts before domain specialized cortical regions that engage in full stimulus analysis according to task demands.


Assuntos
Atenção/fisiologia , Eletrocorticografia , Rede Nervosa/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Córtex Pré-Frontal/fisiologia , Adulto , Biomarcadores , Epilepsia/diagnóstico , Epilepsia/fisiopatologia , Humanos , Leitura
4.
BMC Anesthesiol ; 17(1): 159, 2017 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-29191204

RESUMO

CORRECTION: Following publication of the original article [1], the authors reported that additional file 10 contained a typing error in the table "Percentage of responders (≥50% max TOTPAR) over two, four, six and eight hours (single-dose phase) (ITT Population)". The table is to be read as follows.

5.
Mol Genet Metab ; 118(2): 138-42, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27157420

RESUMO

INTRODUCTION: Telomeres may be considered markers of biological aging, shorter telomere length is associated with some age-related diseases; in several studies short telomere length has also been associated to obesity in adults and adolescents. However the relationship between telomere complex functions and obesity is still not clear. Aim of the study was to assess telomere length (TL) in adults' obese subjects before and after weight loss obtained by placement of bioenteric intragastric balloon (BIB) for 6months. METHODS: We enrolled 42 obese subjects before and after BIB placement as weight loss intervention. Blood samples were collected in order to obtain DNA from leukocyte to measure TL by quantitative PCR. RESULTS: Data were analyzed only in 37 subjects with complete data; all presented important body weight loss (124.06±26.7 vs 105.40±23.14, p<0.001) and more interesting they presented a significant increase in TL (3.58±0.83 vs 5.61±3.29, p<0.001). Moreover we observed a significant positive correlation between TL elongation and weight loss (r=0.44, p=0.007) as well as an inverse correlation between TL at baseline and TL elongation (r=-0.35, p=0.03).The predictors of TL elongation were once again weight loss and short TL at baseline (respectively p=0.007 and p=0.003). CONCLUSIONS: Our study shows that weight loss is associated to telomere lengthening in a positive correlation: the greater weight loss the greater telomere lengthening; moreover telomere lengthening is more significant in those subjects with shortest telomeres at baseline.


Assuntos
Obesidade/genética , Obesidade/terapia , Homeostase do Telômero , Telômero/genética , Redução de Peso/genética , Adolescente , Adulto , Envelhecimento/genética , Feminino , Balão Gástrico , Marcadores Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas , Fatores de Tempo
6.
Br J Anaesth ; 116(2): 269-76, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26787797

RESUMO

BACKGROUND: The aim was to evaluate the analgesic efficacy and safety of the dexketoprofen/tramadol 25 mg/75 mg fixed-dose combination vs dexketoprofen (25 mg) and tramadol (100 mg) in moderate-to-severe acute pain after total hip arthroplasty. METHODS: This was a randomized, double-blind, parallel-group study in patients experiencing pain of at least moderate intensity on the day after surgery, compared with placebo at first administration to validate the pain model. The study drug was administered orally every 8 h throughout a 5 day period. Rescue medication, metamizole 500 mg, was available during the treatment period. The evaluation of efficacy was based on patient assessments of pain intensity and pain relief. The primary end point was the mean sum of the pain intensity difference values throughout the first 8 h (SPID8). RESULTS: Overall, 641 patients, mean age 62 (range 29-80) yr, were analysed; mean (sd) values of SPID8 were 247 (157) for dexketoprofen/tramadol, 209 (155) for dexketoprofen, 205 (146) for tramadol, and 151 (159) for placebo. The primary analysis confirmed the superiority of the combination over dexketoprofen 25 mg (P=0.019; 95% confidence interval 6.4-73) and tramadol 100 mg (P=0.012; 95% confidence interval 9.5-76). The single components were superior to placebo (P<0.05), confirming model sensitivity. Most secondary analyses supported the superiority of the combination. The incidence of adverse drug reactions was low and similar among active treatment groups. CONCLUSION: The efficacy results confirmed the superiority of dexketoprofen/tramadol over its single components, even at higher doses (tramadol), with a safety profile fully in line with that previously known for these agents in monotherapy. CLINICAL TRIAL REGISTRATION: EudraCT 2012-004548-31 (https://www.clinicaltrialsregister.eu/ctr-search/search?query=eudract_number:2012-004548-31);ClinicalTrials.gov NCT01902134 (https://www.clinicaltrials.gov/ct2/show/NCT01902134?term=NCT01902134&rank=1).


Assuntos
Analgésicos Opioides/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Artroplastia de Quadril , Cetoprofeno/análogos & derivados , Dor Pós-Operatória/tratamento farmacológico , Tramadol/uso terapêutico , Trometamina/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Cetoprofeno/uso terapêutico , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do Tratamento
7.
BMC Anesthesiol ; 16: 9, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26801905

RESUMO

BACKGROUND: Dexketoprofen trometamol plus tramadol hydrochloride is a new oral combination of two analgesics, which have different mechanisms of action for the treatment of moderate to severe acute pain. METHODS: Randomised, double-blind, parallel, placebo and active-controlled, single and multiple-dose study to evaluate the analgesic efficacy and safety of dexketoprofen/tramadol 25 mg/75 mg in comparison with the single agents (dexketoprofen 25 mg and tramadol 100 mg) in moderate to severe acute pain after abdominal hysterectomy. Patients received seven consecutive doses of study drug within a 3-day period, each dose separated by an 8-hour interval. A placebo arm was included during the single-dose phase to validate the pain model. Efficacy assessments included pain intensity, pain relief, patient global evaluation and use of rescue medication. The primary endpoint was the mean sum of pain intensity differences over the first 8 h (SPID8). RESULTS: The efficacy analysis included 606 patients, with a mean age of 48 years (range 25-73). The study results confirmed the superiority of the combination over the single agents in terms of the primary endpoint (p <0.001). Secondary endpoints were generally supportive of the superiority of the combination for both single and multiple doses. Most common adverse drug reactions (ADRs) were nausea (4.6%) and vomiting (2.3%). All other ADRs were experienced by less than 2% of patients. CONCLUSIONS: The study results provided robust evidence of the superiority of dexketoprofen/tramadol 25 mg/75 mg over the single components in the management of moderate to severe acute pain, as confirmed by the single-dose efficacy, repeated-dose sustained effect and good safety profile observed. TRIAL REGISTRATION: EU Clinical Trials Register (EudraCT number 2012-004545-32, registered 04 October 2012); Clinicaltrials.gov ( NCT01904149, registered 17 July 2013).


Assuntos
Dor Aguda/tratamento farmacológico , Histerectomia/efeitos adversos , Cetoprofeno/análogos & derivados , Dor Pós-Operatória/tratamento farmacológico , Índice de Gravidade de Doença , Tramadol/administração & dosagem , Trometamina/administração & dosagem , Dor Aguda/diagnóstico , Dor Aguda/etiologia , Adulto , Idoso , Analgésicos Opioides/administração & dosagem , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Cetoprofeno/administração & dosagem , Pessoa de Meia-Idade , Manejo da Dor/métodos , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/etiologia
8.
J Headache Pain ; 16: 541, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26123824

RESUMO

BACKGROUND: Combination analgesics are effective in acute pain, and a theoretical framework predicts efficacy for combinations. The combination of dexketoprofen and tramadol is untested, but predicted to be highly effective. METHODS: This was a randomised, double-blind, double-dummy, parallel-group, placebo-controlled, single-dose trial in patients with moderate or severe pain following third molar extraction. There were ten treatment arms, including dexketoprofen trometamol (12.5 mg and 25 mg) and tramadol hydrochloride (37.5 mg and 75 mg), given as four different fixed combinations and single components, with ibuprofen 400 mg as active control as well as a placebo control. The study objective was to evaluate the superior analgesic efficacy and safety of each combination and each single agent versus placebo. The primary outcome was the proportion of patients with at least 50 % max TOTPAR over six hours. RESULTS: 606 patients were randomised and provided at least one post-dose assessment. All combinations were significantly better than placebo. The highest percentage of responders (72%) was achieved in the dexketoprofen trometamol 25 mg plus tramadol hydrochloride 75 mg group (NNT 1.6, 95% confidence interval 1.3 to 2.1). Addition of tramadol to dexketoprofen resulted in greater peak pain relief and greater pain relief over the longer term, particularly at times longer than six hours (median duration of 8.1 h). Adverse events were unremarkable. CONCLUSIONS: Dexketoprofen trometamol 25 mg combined with tramadol hydrochloride 75 mg provided good analgesia with rapid onset and long duration in a model of moderate to severe pain. The results of the dose finding study are consistent with pre-trial calculations based on empirical formulae. TRIAL REGISTRATION: EudraCT (2010-022798-32); Clinicaltrials.gov (NCT01307020).


Assuntos
Dor Aguda/tratamento farmacológico , Analgésicos Opioides/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Pesquisa Empírica , Cetoprofeno/análogos & derivados , Tramadol/administração & dosagem , Trometamina/administração & dosagem , Dor Aguda/diagnóstico , Adolescente , Adulto , Analgesia/métodos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Cetoprofeno/administração & dosagem , Masculino , Pessoa de Meia-Idade , Manejo da Dor/métodos , Adulto Jovem
9.
Neuroimage ; 90: 298-307, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24370818

RESUMO

The exact role of the left ventral occipitotemporal cortex (VOTC) during the initial stages of reading acquisition is a hotly debated issue, especially regarding the comparative effect of learning on early stimulus-dependent vs. later task-dependent processes. We show that this controversy can be solved with high-temporal resolution intracerebral EEG recordings of the VOTC. We measured High-Frequency Activity (50-150 Hz) as a proxy of population-level spiking activity while participants learned Japanese Katakana symbols, and found that learning primarily affects top-down/task-dependent neural processing, after a few minutes only. In contrast, adaptation of early bottom-up/stimulus-dependent processing takes several days to adapt and provides the basis for fluent reading. Such evidence that two consecutive stages of neural processing, stimulus- and task-dependent are differentially affected by learning, can reconcile seemingly opposite hypotheses on the role of the VOTC during reading acquisition.


Assuntos
Aprendizagem/fisiologia , Lobo Occipital/fisiologia , Leitura , Lobo Temporal/fisiologia , Adulto , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Masculino , Processamento de Sinais Assistido por Computador , Percepção Visual/fisiologia
10.
Opt Express ; 22 Suppl 6: A1547-52, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25607311

RESUMO

The control and tailoring of infrared absorbance/emittance is a crucial task for all those applications involving thermal radiation management and detection. We theoretically investigated the peculiar absorbing/emitting behaviour of pre-fractal Cantor multilayers, in order to design a polarization-insensitive multilayer stack absorbing over a wide angular lobe in the mid wavelength infrared range (8-10 µm). Using transfer matrix method, we explored the spectral properties arising from both the material and the geometrical dispersion. We considered several combinations of the constituent materials: SiO2 was combined with TiO2 and Si, respectively.


Assuntos
Algoritmos , Raios Infravermelhos , Nanopartículas Metálicas/química , Modelos Químicos , Absorção de Radiação , Simulação por Computador , Fractais , Luz , Nanopartículas Metálicas/efeitos da radiação , Espalhamento de Radiação
11.
Sci Rep ; 14(1): 11645, 2024 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773246

RESUMO

The evaluation of cognitive functions interactions has become increasingly implemented in the cognition exploration. In the present study, we propose to examine the organization of the cognitive network in healthy participants through the analysis of behavioral performances in several cognitive domains. Specifically, we aim to explore cognitive interactions profiles, in terms of cognitive network, and as a function of participants' handedness. To this end, we proposed several behavioral tasks evaluating language, memory, executive functions, and social cognition performances in 175 young healthy right-handed and left-handed participants and we analyzed cognitive scores, from a network perspective, using graph theory. Our results highlight the existence of intricate interactions between cognitive functions both within and beyond the same cognitive domain. Language functions are interrelated with executive functions and memory in healthy cognitive functioning and assume a central role in the cognitive network. Interestingly, for similar high performance, our findings unveiled differential organizations within the cognitive network between right-handed and left-handed participants, with variations observed both at a global and nodal level. This original integrative network approach to the study of cognition provides new insights into cognitive interactions and modulations. It allows a more global understanding and consideration of cognitive functioning, from which complex behaviors emerge.


Assuntos
Cognição , Função Executiva , Humanos , Cognição/fisiologia , Masculino , Feminino , Adulto Jovem , Adulto , Função Executiva/fisiologia , Idioma , Lateralidade Funcional/fisiologia , Memória/fisiologia , Testes Neuropsicológicos , Adolescente
12.
Laterality ; 18(2): 216-30, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22489628

RESUMO

In the presented experiment we explored the effect of lexicality on hemisphere specialisation and cooperation during a phonological task. The divided visual field (DVF) method with bilateral presentation (BVF) of redundant (identical) stimuli is considered an appropriate approach to assess inter-hemispheric cooperation (IHC). IHC is supposed to increase the efficiency of cognitive processes. Specifically, it has been shown that, compared to unilateral hemifield presentation, word processing is significantly more efficient if stimuli were presented under bilateral redundancy conditions. The performance enhancement during bilateral vs. unilateral presentation is called bilateral redundant gain (BRG). In the present experiment a DVF was used and participants were required to perform a rhyme detection task in two blocks, one in words and another one in pseudowords. Each item was presented in two different modes, one unilateral (right or left hemi-visual field) and another one bilateral (simultaneous redundant presentation). Unilateral trials allow one to study hemispheric specialisation, while bilateral redundant trials allow one to study inter-hemispheric cooperation. We obtained left hemisphere specialisation for both types of items (word, pseudoword). Moreover, words were more efficiently processed than pseudowords. Additionally, words were processed more efficiently in BVF than in unilateral presentation, inducing BRG. No similar effect was obtained for pseudowords. These results are discussed in respect to findings reported by other studies suggesting that hemispheric specialisation depends on lexicality. Moreover, compared to lexical decision tasks used in previous studies, the phonological task used in the present study seems to modulate the inter-hemispheric cooperation less.


Assuntos
Dominância Cerebral/fisiologia , Campos Visuais/fisiologia , Feminino , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação/fisiologia , Vocabulário , Adulto Jovem
13.
Autoimmunity ; 56(1): 2229072, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37381619

RESUMO

Nowadays, data concerning the risk of autoimmune disease after SARS-CoV-2 (COVID-19) vaccination is controversial. The aim of this single centre prospective follow-up study was to evaluate whether healthcare workers (HCWs) vaccinated with BNT162b2 mRNA and mRNA-1273 will show a development and/or a persistence of autoantibodies, focussing on the detection of antibodies against nuclear antigens (antinuclear antibodies, ANA). We enrolled 155 HCWs, however only 108 of them received the third dose and were considered for further analysis. Blood samples were collected before vaccine inoculation (T0), at 3 (T1) and 12 months (T2) after the first dose. All samples were analysed for the presence of a) ANA using indirect Immunofluorescence [IIF] (dilutions of 1:80, 1:160. 1:320 and 1:640), and anti-smooth muscle antibodies (ASMA); b) anti-myeloperoxidase (anti-MPO), anti-proteinase 3 (anti-PR3) and anti-citrullinated peptide antibodies (aCCP) [FEIA]; c) anti-phospholipid antibodies (anticardiolipin [aCL], anti-beta-2- glycoprotein I [anti-ß-2GPI] (Chemiluminescence). Line-blot technology was performed using the following kit: EUROLINE ANA profile 3 plus DFS70 (IgG). Our research suggests that mRNA based anti-SARSCoV-2 vaccines can induce the production of de novo ANA in 22/77(28,57%) of subjects and that the percentage of positivity seems to be directly correlated to the number of vaccine expositions: 6/77 (7,79%) after 2 doses; 16/77 (20,78%) after 3 doses. Since it is known that hyperstimulation of the immune system could lead to autoimmunity, these preliminary results seem to further sustain the idea that the hyperstimulation of the immune system might lead to an autoinflammatory mechanism and eventually to autoimmune disorders. However, the link between SARS-CoV-2 vaccination and the development of autoimmune diseases needs to be further investigated.


Assuntos
Doenças Autoimunes , COVID-19 , Humanos , Autoanticorpos , Vacinas contra COVID-19/efeitos adversos , Seguimentos , Vacina BNT162 , Estudos Prospectivos , COVID-19/prevenção & controle , SARS-CoV-2 , Doenças Autoimunes/etiologia , Pessoal de Saúde
14.
Epilepsy Behav ; 23(1): 81-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22197719

RESUMO

This study explores the language reorganization before and after surgery in a 55-year-old right-handed female patient presenting with left temporal refractory epilepsy. Two aspects of language were explored, phonological and semantic, by using neuropsychological assessments and fMRI protocols. To assess the possible reorganization of language, fMRI results for B.L. were compared with results obtained in a group of healthy control subjects (results not presented in detail). According to our results and compared with healthy subjects, B.L. shows reorganization of temporal regions only. The reorganization had various patterns according to the task. Before surgery, neuropsychological testing in B.L. revealed impairment in phonological abilities and fMRI suggested right temporal involvement (interhemisphere reorganization) during the phonological task; semantic abilities were unaltered and fMRI showed bilateral activation of temporal regions during the semantic task. After surgery, the phonological deficit disappeared and fMRI showed left perilesional location of temporal activation (intrahemispheric reorganization); semantic abilities remain preserved and temporal activation remained located bilaterally but predominantly to the right during the semantic task. Our results suggest that cerebral reorganization of language depends on the language operation tested. Moreover, the results underline the importance of differential assessment of language operations and show functional reorganization after beneficial surgery in an older patient.


Assuntos
Epilepsia do Lobo Temporal/complicações , Epilepsia do Lobo Temporal/cirurgia , Transtornos da Linguagem/etiologia , Mapeamento Encefálico , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/cirurgia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Idioma , Transtornos da Linguagem/cirurgia , Testes de Linguagem , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Testes Neuropsicológicos , Lobo Temporal/irrigação sanguínea
15.
Nutr Metab Cardiovasc Dis ; 22(10): 823-30, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21546230

RESUMO

BACKGROUND AND AIMS: The first step in the alternative pathway of bile acid biosynthesis is the 27-hydroxylation of cholesterol, which takes place both in liver and extrahepatic tissues. This pathway is believed to play a role in peripheral cholesterol degradation. Aim of this study was to investigate the impact of hyperlipidemia on 27-hydroxycholesterol appearance rate, and to assess the effects induced by treatment with statins. METHODS AND RESULTS: Seven patients with familial hypercholesterolemia and eight patients with familial combined hyperlipidemia underwent determination of 27-hydroxylation rates in vivo by i.v. infusion of deuterated 27-hydroxycholesterol. Isotope enrichment was assayed by gas chromatography-mass spectrometry, allowing to calculate 27-hydroxycholesterol appearance rates. Six normocholesterolemic subjects were regarded as controls. In some hypercholesterolemic patients the infusions were repeated during treatment with atorvastatin or rosuvastatin. Hydroxylation rates were higher in hypercholesterolemic patients (8.7 ± 2.5 mg/h; controls, 3.4 ± 2.0 mg/h; combined hyperlipidemia, 4.4 ± 1.6 mg/h; mean ± SD, P < 0.01 vs both). After statin treatment, both plasma cholesterol levels and hydroxylation rates dropped by nearly 50%. No difference was detectable between the two statins. A linear correlation was shown between plasma cholesterol and 27-hydroxylation rates. CONCLUSION: Hypercholesterolemia associates with increased 27-hydroxycholesterol appearance rates, which decrease during hypocholesterolemic treatment. The correlation with cholesterol levels supports the view that 27-hydroxylation may act as a compensatory mechanism in a condition of larger plasma cholesterol pool. A regulatory role for hepatic and extrahepatic nuclear receptors seems reasonable. These data prompt novel pharmacological approaches for the management of hypercholesterolemia and the prevention of atherosclerosis.


Assuntos
Hidroxicolesteróis/sangue , Hipercolesterolemia/sangue , Hipercolesterolemia/tratamento farmacológico , Adulto , Idoso , Anticolesterolemiantes/uso terapêutico , Atorvastatina , Estudos de Casos e Controles , Colesterol/sangue , Colesterol/metabolismo , Feminino , Fluorbenzenos/uso terapêutico , Cromatografia Gasosa-Espectrometria de Massas , Ácidos Heptanoicos/uso terapêutico , Humanos , Hidroxilação , Hipercolesterolemia/fisiopatologia , Hiperlipidemia Familiar Combinada/tratamento farmacológico , Hiperlipidemia Familiar Combinada/fisiopatologia , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Hiperlipoproteinemia Tipo II/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Rosuvastatina Cálcica , Sulfonamidas/uso terapêutico
16.
Nutr Metab Cardiovasc Dis ; 21(11): 885-92, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20674312

RESUMO

BACKGROUND AND AIM: This study aims to analyse the risk of cardiovascular events in a local cohort of patients with type 2 diabetes, and to evaluate the prognostic accuracy of four algorithms used to estimate cardiovascular risk: the Framingham study, United Kingdom Prospective Diabetes Study (UKPDS), Riskard study and Progetto Cuore. METHOD AND RESULTS: We analysed clinical charts of the Diabetes Clinics of Modena for the period 1991-95. Patients in the age range of 35-65 with type 2 diabetes and no previous cardiovascular disease were eligible. The incidence of new cardiovascular disease was compared with estimated rates deriving from the different functions. A stratification was obtained in subgroups at different cardiovascular risk, allowing comparison between the algorithms. A total of 1532 patients were eligible; women presented a worse cardiovascular risk profile. An absolute 10-year rate of cardiovascular events of 14.9% was observed. Comparing patients with events with event-free subjects, we found significant differences in systolic blood pressure, age at visit, smoking, high-density lipoprotein (HDL)-cholesterol, duration of diabetes, glycosylated haemoglobin (HbA1c) and co-morbidities. Comparing the estimated risk rate according to the different functions, Italian algorithms were more consistent with observed data; however, Progetto Cuore and Riskard show underestimation of events when applied to females. CONCLUSIONS: Estimation of cardiovascular risk is dependent on the algorithm adopted and on the baseline risk of the reference cohort. Functions designed for a specific population, including risk variables peculiar for diabetes, should be adopted to increase the performance of such functions which is clearly unsatisfactory at present.


Assuntos
Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Adulto , Fatores Etários , Idoso , Algoritmos , Pressão Sanguínea , HDL-Colesterol/sangue , Feminino , Hemoglobinas Glicadas/análise , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Fumar/epidemiologia
17.
Opt Express ; 17(19): 17000-9, 2009 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-19770918

RESUMO

We analyze the relationship between the bound and the free waves in the noncollinear SHG scheme, along with the vectorial conservation law for the different components arising when there are two pump beams impinging on the sample with two different incidence angles. The generated power is systematically investigated, by varying the polarization state of both fundamental beams, while absorption is included via the Herman and Hayden correction terms. The theoretical simulations, obtained for samples which are some coherence length thick show that the resulting polarization mapping is an useful tool to put in evidence the interference between bound and free waves, as well as the effect of absorption on the interference pattern.

18.
Opt Express ; 17(22): 19337-44, 2009 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-19997154

RESUMO

We present a scheme of XOR/XNOR logic gate, based on non phase-matched noncollinear second harmonic generation from a medium of suitable crystalline symmetry, Gallium nitride. The polarization of the noncollinear generated beam is a function of the polarization of both pump beams, thus we experimentally investigated all possible polarization combinations, evidencing that only some of them are allowed and that the nonlinear interaction of optical signals behaves as a polarization based XOR. The experimental results show the peculiarity of the nonlinear optical response associated with noncollinear excitation, and are explained using the expression for the effective second order optical nonlinearity in noncollinear scheme.


Assuntos
Gálio/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/instrumentação , Dispositivos Ópticos , Refratometria/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Dinâmica não Linear
19.
Curr Med Chem ; 15(22): 2271-84, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18781949

RESUMO

The liver plays a central role in the regulation of cholesterol homeostasis. Hepatic cholesterol content is maintained by a complex interplay between input and output pathways; alterations in the balance among these processes may lead to accumulation of excess cholesterol in body compartments with potentially deleterious consequences at the level of blood vessels (atherosclerosis) and biliary tract (gallstone disease). Molecular biology has brought new insights into this field. Nuclear receptors have been shown to play a key role in the "sensing" of intracellular cholesterol levels and in the triggering of metabolic responses via the sterol regulatory element binding protein (SREBP) cascade. A nuclear receptor for bile acids, farnesoid X receptor (FXR), has been identified and the molecular pathways underlying feedback inhibition of bile acid synthesis, the main mechanism of irreversible degradation of cholesterol, have been clarified. Such regulation involves a number of additional coactivators/corepressors of the transcription of the limiting enzyme of bile acid synthesis, cholesterol 7alpha-hydroxylase. Finally, the main transporters of biliary lipids (bile acids, phospholipids and cholesterol) have been described; most of them undergo transcriptional control by nuclear receptors, allowing regulation of biliary lipid efflux in conditions of different intracellular availability. Despite a body of evidence coming from experimental models the intimate mechanisms of regulation have not been clearly defined and direct evidence in humans is rather limited. This review will focus on the role of nuclear receptors in the regulation of hepatic cholesterol degradation and biliary lipid secretion, and on the theoretical applications from a pharmacotherapeutic perspective.


Assuntos
Colesterol/metabolismo , Cálculos Biliares/metabolismo , Fígado/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Ácidos e Sais Biliares/biossíntese , Ácidos e Sais Biliares/metabolismo , Humanos , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo
20.
Clin Genet ; 74(3): 267-73, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18492086

RESUMO

Homozygous familial hypobetalipoproteinaemia (Ho-FHBL) is a rare co-dominant disorder characterized by extremely low levels of low-density lipoprotein cholesterol (LDL-C) and apolipoprotein B (apoB). Most patients with Ho-FHBL have mutations in APOB gene resulting in truncated apoBs. Some patients are asymptomatic, while others have fatty liver, intestinal fat malabsorption and neurological dysfunctions. We investigated three adult subjects with severe hypobetalipoproteinaemia and a family history of FHBL. Proband FHBL-47 had liver cirrhosis with hepatocarcinoma and a renal carcinoma but no clinical manifestations related to FHBL. He was a compound heterozygote for a 7-bp deletion in exon 21 and a base insertion in exon 26 resulting in truncated apoBs (apoB-22.46/apoB-66.51). Proband FHBL-53, with severe hepatic steatosis and fibrosis, had a nonsense mutation in exon 19 resulting in a truncated apoB (apoB-20.61) and a rare nucleotide substitution in intron 14 (c.2068-4T>A). The latter was also present in her daughter, found to have low plasma LDL-C and apoB. Proband FHBL-82 had chronic diarrhoea and steatorrhoea. She was found to be homozygous for a nonsense mutation in exon 24 resulting in a truncated apoB (apoB-26.65). In adult subjects, the presence of chronic liver disease and chronic diarrhoea, when associated with severe hypobetalipoproteinaemia, may lead to the diagnosis of Ho-FHBL.


Assuntos
Apolipoproteínas B/genética , Variação Genética , Homozigoto , Hipobetalipoproteinemia Familiar por Apolipoproteína B/genética , Mutação/genética , Adulto , Idoso de 80 Anos ou mais , Apolipoproteínas B/metabolismo , Sequência de Bases , Análise Mutacional de DNA , Feminino , Humanos , Hipobetalipoproteinemia Familiar por Apolipoproteína B/patologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linhagem , Fenótipo
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