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1.
Neurocase ; 27(4): 338-348, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34503393

RESUMEN

Decades of neuroscientific findings have elucidated the highly specialized brain areas involved in reading, especially along the ventral occipitotemporal stream where the critical step of recognizing words occurs. We report on a 14-year-old female with temporary dyslexia after a left ventral occipitotemporal ischemic stroke. Our longitudinal multimodal findings show that the resolution of the reading impairment was associated with heightened activity in the left posterior superior and inferior temporal gyri. Our findings highlight the role of the left inferior temporal gyrus in reading and the importance of perilesional and ipsilateral cortical areas for functional recovery after childhood stroke.


Asunto(s)
Dislexia , Accidente Cerebrovascular , Adolescente , Encéfalo , Mapeo Encefálico , Niño , Dislexia/etiología , Femenino , Humanos , Imagen por Resonancia Magnética , Lectura , Accidente Cerebrovascular/complicaciones
2.
Neuroimage Clin ; 28: 102369, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32798912

RESUMEN

Post-mortem studies show that focal anterior temporal lobe (ATL) neurodegeneration is most often caused by frontotemporal lobar degeneration TDP-43 type C pathology. Clinically, these patients are described with different terms, such as semantic variant primary progressive aphasia (svPPA), semantic dementia (SD), or right temporal variant frontotemporal dementia (FTD) depending on whether the predominant symptoms affect language, semantic knowledge for object or people, or socio-emotional behaviors. ATL atrophy presents with various degrees of lateralization, with right-sided cases considered rarer even though estimation of their prevalence is hampered by the paucity of studies on well-characterized, pathology-proven cohorts. Moreover, it is not clear whether left and right variants show a similar distribution of atrophy within the ATL cross-sectionally and longitudinally. Here we study the largest cohort to-date of pathology-proven TDP-43-C cases diagnosed during life as svPPA, SD or right temporal variant FTD. We analyzed clinical, cognitive, and neuroimaging data from 30 cases, a subset of which was followed longitudinally. Guided by recent structural and functional parcellation studies, we constructed four bilateral ATL regions of interest (ROIs). The computation of an atrophy lateralization index allowed the comparison of atrophy patterns between the two hemispheres. This led to an automatic, imaging-based classification of the cases as left-predominant or right-predominant. We then compared the two groups in terms of regional atrophy patterns within the ATL ROIs (cross-sectionally) and atrophy progression (longitudinally). Results showed that 40% of pathology proven cases of TDP-43-C diagnosed with a temporal variant presented with right-lateralized atrophy. Moreover, the findings of our ATL ROI analysis indicated that, irrespective of atrophy lateralization, atrophy distribution within both ATLs follows a medial-to-lateral gradient. Finally, in both left and right cases, atrophy appeared to progress to the contralateral ATL, and from the anterior temporal pole to posterior temporal and orbitofrontal regions. Taken together, our findings indicate that incipient right predominant ATL atrophy is common in TDP-43-C pathology, and that distribution of damage within the ATLs appears to be the same in left- and right- sided variants. Thus, regardless of differences in clinical phenotype and atrophy lateralization, both temporal variants of FTD should be viewed as a spectrum presentation of the same disease.


Asunto(s)
Demencia Frontotemporal , Degeneración Lobar Frontotemporal , Atrofia/patología , Demencia Frontotemporal/diagnóstico por imagen , Demencia Frontotemporal/patología , Degeneración Lobar Frontotemporal/diagnóstico por imagen , Degeneración Lobar Frontotemporal/patología , Humanos , Imagen por Resonancia Magnética , Neuroimagen , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/patología
3.
Theriogenology ; 83(4): 478-84, 2015 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-25459031

RESUMEN

The aim of this work was to determine the effects of dark and light conditions on the E2, testosterone and thyroid hormones levels and on the gene expression levels (vitellogenin 1, vitellogenin 2, and estradiol receptor one) in European eels (Anguilla anguilla) during ovarian development induced by increasing doses of carp pituitary extracts (CPEs). The subjects were divided into 2 groups: 14-hour light:10-hour dark (Light Group) and 24-hour darkness (Dark Group). All the eels received intramuscular injections with CPE at a dosage of 10 mg/kg body weight (BW) once a week for the first 3 weeks, 20 mg/kg BW fourth-sixth week, 30 mg/kg BW seventh-ninth week, and 40 mg/kg up to the end of the experiment (13th week). Vitellogenin and estradiol receptor expression levels did not show significant differences between the two housing conditions whereas in both groups vitellogenin mRNA increased starting from first CPE injection. Testosterone and 17-beta estradiol plasma levels were significantly greater in the Dark Group compared with the Light Group starting from the ninth and the 13th week, respectively. These results suggest that darkness could be a useful variable for standardizing gonadal maturation in eels kept in captivity.


Asunto(s)
Anguilas/fisiología , Estrógenos/metabolismo , Fotoperiodo , Testosterona/metabolismo , Extractos de Tejidos/farmacología , Vitelogeninas/metabolismo , Animales , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/fisiología , Hipófisis , Receptores de Estradiol/genética , Receptores de Estradiol/metabolismo , Hormonas Tiroideas/sangre , Hormonas Tiroideas/metabolismo , Extractos de Tejidos/administración & dosificación , Vitelogeninas/genética
4.
Neuroimage Clin ; 4: 426-35, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24624328

RESUMEN

Diffusion Weighted Imaging is extremely important for the diagnosis of probable sporadic Jakob-Creutzfeldt disease, the most common human prion disease. Although visual assessment of DWI MRI is critical diagnostically, a more objective, quantifiable approach might more precisely identify the precise pattern of brain involvement. Furthermore, a quantitative, systematic tracking of MRI changes occurring over time might provide insights regarding the underlying histopathological mechanisms of human prion disease and provide information useful for clinical trials. The purposes of this study were: 1) to describe quantitatively the average cross-sectional pattern of reduced mean diffusivity, fractional anisotropy, atrophy and T1 relaxation in the gray matter (GM) in sporadic Jakob-Creutzfeldt disease, 2) to study changes in mean diffusivity and atrophy over time and 3) to explore their relationship with clinical scales. Twenty-six sporadic Jakob-Creutzfeldt disease and nine control subjects had MRIs on the same scanner; seven sCJD subjects had a second scan after approximately two months. Cortical and subcortical gray matter regions were parcellated with Freesurfer. Average cortical thickness (or subcortical volume), T1-relaxiation and mean diffusivity from co-registered diffusion maps were calculated in each region for each subject. Quantitatively on cross-sectional analysis, certain brain regions were preferentially affected by reduced mean diffusivity (parietal, temporal lobes, posterior cingulate, thalamus and deep nuclei), but with relative sparing of the frontal and occipital lobes. Serial imaging, surprisingly showed that mean diffusivity did not have a linear or unidirectional reduction over time, but tended to decrease initially and then reverse and increase towards normalization. Furthermore, there was a strong correlation between worsening of patient clinical function (based on modified Barthel score) and increasing mean diffusivity.


Asunto(s)
Envejecimiento/patología , Encéfalo/patología , Síndrome de Creutzfeldt-Jakob/patología , Imagen de Difusión Tensora/métodos , Sustancia Gris/patología , Interpretación de Imagen Asistida por Computador/métodos , Algoritmos , Síndrome de Creutzfeldt-Jakob/diagnóstico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
5.
Pediatr Med Chir ; 35(6): 253-8, 2013.
Artículo en Italiano | MEDLINE | ID: mdl-24620551

RESUMEN

In general population about 15-20% of subjects have suffered from one episode of urticaria-angioedema syndrome in their life. The etiology of his condition is various and multifactorial. In children the principal cause of acute urticaria is infection, while physical factors are the main agents of chronic urticaria. All those conditions which lack an etiology are named chronic idiopathic urticaria, but in reality a considerable number of these patients is affected by a chronic autoimmune urticaria. For this reason, screening out the most frequent causes of chronic urticaria, it's useful to know when it's possible to apply specific diagnostic tests for this condition and which therapies are employable.


Asunto(s)
Pediatría , Urticaria/diagnóstico , Angioedema/diagnóstico , Niño , Enfermedad Crónica , Diagnóstico Diferencial , Antagonistas de los Receptores Histamínicos/uso terapéutico , Humanos , Incidencia , Italia/epidemiología , Síndrome , Urticaria/tratamiento farmacológico , Urticaria/epidemiología , Urticaria/etiología
6.
Pediatr Med Chir ; 35(5): 205-11, 2013.
Artículo en Italiano | MEDLINE | ID: mdl-24516940

RESUMEN

In the last few years we have observed an upward trend in the employment of ibuprofen as anti-inflammatory and antipyretic therapy. Therefore the pediatrician has often a precious option in the anti-inflammatory and antipyretic treatment in children instead of using steroids and paracetamol. In clinical practice ibuprofen can be used in the treatment of headache, toothache, otalgy, dysmenorrhea, neuralgia, arthralgia, myalgia, abdominal pain and fever: it is the first choice for these common diseases. However, the use of steroids is a routine, even if non-corticosteroid anti-inflammatory molecules could be useful. Certainly steroids are powerful anti-inflammatory, indicated for the treatment of chronic inflammatory disorders and in acute respiratory and allergic diseases. Beside, thanks to their chemical and pharmacological profile, they also provide patients with an antipyretic effect. However, the use of steroids must be reserved to cases in which other classical antipyretics such as non-steroidal anti-inflammatory drugs are not effective. The possible side effects and risks associated with stepping down steroids must be considered. Although "steroids-phobia" should be discouraged, steroids are to be reserved only as the first indication. In all other cases the pediatrician can use ibuprofen, whose efficacy and safety are widely demonstrated by now.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Glucocorticoides/uso terapéutico , Ibuprofeno/uso terapéutico , Antiinflamatorios no Esteroideos/efectos adversos , Niño , Fiebre/tratamiento farmacológico , Glucocorticoides/efectos adversos , Humanos , Ibuprofeno/efectos adversos , Inflamación/tratamiento farmacológico
7.
AJNR Am J Neuroradiol ; 33(1): 180-7, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21998099

RESUMEN

BACKGROUND AND PURPOSE: The connectivity across brain regions can be evaluated through fMRI either by using ICA or by means of correlation analysis of time courses measured in predefined ROIs. The purpose of this study was to investigate quantitatively the correspondence between the connectivity information provided by the 2 techniques. MATERIALS AND METHODS: In this study, resting-state fMRI data from 40 healthy participants were independently analyzed by using spatial ICA and ROI-based analysis. To assess the correspondence between the results provided by the 2 methods, for all combinations of ROIs, we compared the time course correlation coefficient with the corresponding "ICA coactivation index." RESULTS: A strongly significant correspondence of moderate intensity was found for 20 ICA components (r = 0.44, P < .001). Repeating the analysis with 10, 15, 25, 30, 35, and 40 components, we found that the correlation remained but was weaker (r = 0.35-0.41). CONCLUSIONS: There is a significant but not complete correspondence between the results provided by ICA and ROI-based analysis of resting-state data.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Red Nerviosa/fisiología , Descanso/fisiología , Adulto , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Vías Nerviosas/fisiología , Análisis de Componente Principal , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estadística como Asunto
8.
AJNR Am J Neuroradiol ; 31(4): 706-10, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19942704

RESUMEN

BACKGROUND AND PURPOSE: The neostriatum is known to be affected in HD. In this work, our aim was to determine whether microstructural and volumetric alterations occur in the neostriatum of presymptomatic HD gene carriers and in patients with early-stage HD. MATERIALS AND METHODS: We studied a group of 15 presymptomatic gene carriers who were far from the estimated symptom onset (16% probability of developing the disease within 5 years), a group of 9 patients with early symptomatic HD, and 2 groups of age-matched controls. Volumetric MR imaging and DWIs were acquired, and statistical analyses were performed on the volumes of the caudate nucleus and putamen and on the corresponding MD measurements. RESULTS: Neostriatal volumes were significantly smaller in both presymptomatic HD gene carriers and symptomatic patients with respect to controls. However, whereas the diffusivity in the caudate nucleus was increased in the symptomatic patients, it was decreased in the presymptomatic gene carriers. CONCLUSIONS: Altered diffusivity and reduced volume of the caudate nucleus in presymptomatic HD gene carriers indicate that the neostriatum is affected well before the onset of symptoms. The observed initial decrease and subsequent increase of MD might be related to the combined effect of increased oligodendroglial population, putatively a developmental abnormality, and incipient neurodegeneration.


Asunto(s)
Núcleo Caudado/patología , Imagen de Difusión por Resonancia Magnética/métodos , Tamización de Portadores Genéticos , Enfermedad de Huntington/diagnóstico , Enfermedad de Huntington/genética , Procesamiento de Imagen Asistido por Computador/métodos , Adulto , Diagnóstico Precoz , Femenino , Predisposición Genética a la Enfermedad/genética , Humanos , Masculino , Persona de Mediana Edad , Putamen/patología , Valores de Referencia
9.
AJNR Am J Neuroradiol ; 30(8): 1482-7, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19589886

RESUMEN

BACKGROUND AND PURPOSE: In progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD), postmortem studies show different topographic involvement of the thalamus, basal ganglia, and their cortical connections. Diffusion tensor imaging (DTI) is an MR imaging technique sensitive to gray and white matter microstructure integrity. This study was performed to determine whether DTI may demonstrate microstructural differences between PSP and CBD, particularly within the thalamus and its cortical connections. MATERIALS AND METHODS: Nine patients with probable PSP, 11 with probable CBD, and 7 controls formed the study group. Apparent diffusion coefficient average (ADC(ave)) and fractional anisotropy (FA) values were measured in regions of interest positioned in the ventrolateral (motor), medial, anterior, and posterior regions of the thalami, basal ganglia, fronto-orbital white matter, cingulum, supplementary motor area (SMA), and precentral and postcentral gyri in patients and controls. RESULTS: In PSP, ADC(ave) values were increased in several areas: the thalamus, particularly in its anterior and medial nuclei; cingulum; motor area; and SMA. FA values were particularly decreased in the fronto-orbital white matter, anterior cingulum, and motor area. In CBD, ADC(ave) was increased in the motor thalamus, in the precentral and postcentral gyri, ipsilateral to the affected frontoparietal cortex, and in the bilateral SMA. FA was mainly decreased in the precentral gyrus and SMA, followed by the postcentral gyrus and cingulum. CONCLUSIONS: In patients with PSP, thalamic involvement was diffuse and prevalent in its anterior part, whereas in CBD involvement was asymmetric and confined to the motor thalamus. DTI may be useful in the differential diagnosis of these 2 parkinsonian disorders.


Asunto(s)
Corteza Cerebral/patología , Imagen de Difusión por Resonancia Magnética/métodos , Enfermedades Neurodegenerativas/patología , Parálisis Supranuclear Progresiva/patología , Tálamo/patología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vías Nerviosas/patología
10.
Neurol Sci ; 30 Suppl 1: S71-4, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19415430

RESUMEN

Withdrawal is the first step for treating patients with chronic migraine and medication overuse. Recent studies confirmed common elements in personality between these patients and subjects addicted; some neuroimaging researches showed that abnormalities revealed are related to a specific cerebral pattern and that they can return to the normal state after withdrawal. Aim of the study was to submit a group of patients suffering from chronic migraine and medication overuse (the diagnosis was made according to Silberstein-Lipton criteria) to a withdrawal, to evaluate by f-MRI the presence of specific cerebral patterns before treatment and their possible changes after withdrawal. f-MRI seems to be a useful technique to obtain information on particular neuronal changes of the pain network involved in this type of patients. The activated areas are congruent with some data of the literature and the data emerged are discussed according to preceding reports.


Asunto(s)
Analgésicos/efectos adversos , Encéfalo/fisiopatología , Cefaleas Secundarias/fisiopatología , Trastornos Migrañosos/fisiopatología , Dolor/fisiopatología , Adulto , Analgésicos/uso terapéutico , Mapeo Encefálico , Enfermedad Crónica , Femenino , Cefaleas Secundarias/terapia , Humanos , Imagen por Resonancia Magnética , Trastornos Migrañosos/tratamiento farmacológico , Dimensión del Dolor , Umbral del Dolor , Psicofísica , Síndrome de Abstinencia a Sustancias/fisiopatología
11.
NMR Biomed ; 21(1): 2-14, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17458921

RESUMEN

Rank-2 tensors are unable to represent multi-modal diffusion associated with intra-voxel orientational heterogeneity (IVOH), which occurs where axons are incoherently oriented, such as where bundles intersect or diverge. Under this condition, they are oblate or spheroidally shaped, resulting in artefactually low anisotropy, potentially masking reduced axonal density, myelinisation and integrity. Higher rank tensors can represent multi-modal diffusion, and suitable metrics such as generalised anisotropy (GA) and scaled entropy (SE) have been introduced. The effect of tensor rank was studied through simulations, and analysing high angular resolution diffusion imaging (HARDI) data from two volunteers, fit with rank-2, rank-4 and rank-6 tensors. The variation of GA and SE as a function of rank was investigated through difference maps and region of interest (ROI)-based comparisons. Results were correlated with orientation distribution functions (ODF) reconstructed with q-ball, and with colour-maps of the principal and second eigenvectors. Simulations revealed that rank-4 tensors are able to represent multi-modal diffusion, and that increasing rank further has a minor effect on measurements. IVOH was detected in subcortical regions of the corona radiata, along the superior longitudinal fasciculus, in the radiations of the genu of the corpus callosum, in peritrigonal white matter and along the inferior fronto-occipital and longitudinal fascicula. In these regions, elevating tensor rank increased anisotropy. This was also true for the corpus callosum, cingulum and anterior limb of the internal capsule, where increasing tensor rank resulted in patterns that, although mono-modal, were more anisotropic. In these regions the second eigenvector was coherently oriented. As rank-4 tensors have only 15 distinct elements, they can be determined without acquiring a large number of directions. By removing artefactual underestimation of anisotropy, their use may increase the sensitivity to pathological change.


Asunto(s)
Encéfalo/fisiología , Imagen de Difusión por Resonancia Magnética/métodos , Adulto , Anisotropía , Simulación por Computador , Entropía , Femenino , Humanos , Masculino
12.
AJNR Am J Neuroradiol ; 28(10): 1996-2000, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17998418

RESUMEN

BACKGROUND AND PURPOSE: Structural MR imaging does not enable reliable differentiation of spinocerebellar ataxia (SCA) types 1 and 2 (SCA1 and SCA2), and imaging may be normal during the first years after the onset of symptoms. We aimed at determining whether measurements of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) may enable their differentiation. MATERIALS AND METHODS: We enrolled 14 patients with SCA1, 11 with SCA2, and 9 age-matched controls. Diffusion tensor imaging (DTI) was performed on a 1.5T scanner, with b = 1000s/mm2 and 12 directions. ADC and FA were measured by means of regions of interest, positioned in the corticospinal tract at the level of the cerebral peduncle and at the level of the pons, in the transverse pontine fibers, in the superior and middle cerebellar peduncle, and in the hemispheric cerebellar white matter. RESULTS: With respect to controls, the ADC was significantly elevated in the middle cerebellar peduncle and in hemispheric white matter in SCA1, and in all regions under consideration in SCA2. It was significantly higher in SCA2 than in SCA1 in all regions under consideration. With respect to controls, the FA was significantly reduced in all regions under consideration in SCA1 and in SCA2. It was significantly lower in SCA2 than in SCA1 in the transverse pontine fibers and in the corticospinal tract at the level of the cerebral peduncle. Correlations with clinical scores were found. CONCLUSIONS: DTI did not enable differentiation between SCA1 and SCA2. However, strongly significant differences between the 2 subtypes and with respect to controls and correlations with clinical scores were found.


Asunto(s)
Cerebelo/patología , Imagen de Difusión por Resonancia Magnética , Ataxias Espinocerebelosas/diagnóstico , Adulto , Anisotropía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Puente/patología , Tractos Piramidales/patología , Ataxias Espinocerebelosas/patología
13.
Eur J Neurosci ; 21(2): 549-55, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15673454

RESUMEN

We have examined the characteristics of vergence-induced reduction of ocular counter-roll in near vision. Monkeys were trained to make convergent and divergent refixations with the head and body either upright or in various roll orientations. During near viewing requiring 17 degrees horizontal vergence, we found that static binocular torsion was suppressed by about 68% (averaged over both eyes, two monkeys and both near target locations). This result is in accordance with a previous study in which binocular torsion was quantified based on the displacement planes of eye positions in far and near viewing. Latency and duration of the change in torsional eye position depended (for each eye differently) on body roll and the depth plane of fixation. For instance, during convergent refixations in left-ear-down orientations, the latencies of the left eye were smaller and the durations were longer than those of the right eye. However, both eyes reached their final positions required to fixate the second visual target at roughly the same time. The different dynamics of the two eyes is explained by the fact that each eye rotated temporally when the eyes converged, a pattern named binocular extension of Listing's law. Coming from or aiming at a common torsional value (normal ocular counter-roll) in convergent or divergent refixations, the required torsion differs in the two eyes. The brain compensates for these differences by adjusting the dynamics of each eye's movement.


Asunto(s)
Convergencia Ocular/fisiología , Fijación Ocular/fisiología , Miopía/fisiopatología , Dinámicas no Lineales , Estimulación Acústica/métodos , Análisis de Varianza , Animales , Lateralidad Funcional/fisiología , Macaca mulatta , Modelos Biológicos
14.
Mol Pharmacol ; 59(3): 442-5, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11179437

RESUMEN

Diazepam is used clinically for its myorelaxant, anxiolytic, sedative, and anticonvulsant properties. Although the anxiolytic action is mediated by alpha2 gamma-aminobutyric acid A (GABA(A)) receptors, the sedative action and in part the anticonvulsant action are mediated by alpha1 GABA(A) receptors. To identify the GABA(A) receptor subtypes mediating the action of diazepam on muscle tone, we have assessed the myorelaxant properties of diazepam in alpha2(H101R) and alpha3(H126R) knock-in mice harboring diazepam-insensitive alpha2 or alpha3 GABA(A) receptors, respectively. Whereas in alpha2(H101R) mice the myorelaxant action of diazepam was almost completely abolished at doses up to 10 mg/kg, the same dose induced myorelaxation in both wild-type and alpha3(H126R) mice. It was only at a very high dose (30 mg/kg diazepam) that alpha2(H101R) mice showed partial myorelaxation and alpha3(H126R) mice were partially protected from myorelaxation compared with wild-type mice. Thus, the myorelaxant activity of diazepam seems to be mediated primarily by alpha2 GABA(A) receptors and at high concentrations also by alpha3 GABA(A) receptors.


Asunto(s)
Diazepam/farmacología , Relajantes Musculares Centrales/farmacología , Animales , Anticonvulsivantes/farmacología , Baclofeno/farmacología , Femenino , Agonistas del GABA/farmacología , Agonistas de Receptores GABA-B , Masculino , Ratones , Actividad Motora/efectos de los fármacos , Mutación , Receptores de GABA-A/genética , Receptores de GABA-A/fisiología , Receptores de GABA-B/metabolismo
15.
Stroke ; 26(9): 1691-6, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7660416

RESUMEN

BACKGROUND AND PURPOSE: The aim of the study was to assess whether excessive alcohol intake is an independent risk factor for stroke. METHODS: A case-control study was undertaken in 200 consecutive ischemic and hemorrhagic stroke patients and 372 age- and sex-matched control subjects (170 hospital-based and 202 community-based individuals). Data were collected through direct interview regarding demographics, risk factors for stroke, current daily alcohol consumption, and diagnosis of alcoholism. Blood was also taken to test the common biological markers of alcohol intake (erythrocyte mean cell volume, uric acid, aspartate aminotransferase, and gamma-glutamyl transferase). RESULTS: After controlling for the most significant risk factors (antecedent strokes, hypertension, diabetes, smoking) and using hospital control subjects for reference, we determined the risk of stroke to be 2.2 (95% confidence interval [CI], 1.2 to 4.0) in moderate drinkers (men, < or = 60 g/d; women, < or = 40 g/d) and 2.9 (95% CI, 1.4 to 6.1) in heavy drinkers (men, > 60 g/d; women, > 40 g/d). The corresponding risk values obtained when we compared case subjects and external control subjects were 1.4 (95% CI, 0.8 to 2.7) and 3.0 (95% CI, 1.3 to 7.0). Even with some fluctuations across groups, the risk did not change significantly after subgroup analysis in men, patients with first-ever stroke, patients with ischemic stroke, and after exclusion of subjects with risk factors for stroke. Compared with hospital and external control subjects, stroke patients included a higher proportion of heavy drinkers (26.6% versus 20.6% versus 10.8%), alcoholics (14.6% versus 7.7% versus 2.5%), and cases with abnormal erythrocyte mean cell volume (63.0% versus 47.6% versus 34.2%) or gamma-glutamyl transferase (35.5% versus 32.4% versus 12.9%). Mean alcohol consumption was 42.2 g/d in the case subjects, 30.8 g/d in the hospital control subjects, and 23.2 g/d in the external control subjects. CONCLUSIONS: The study indicates that alcohol can be considered an independent risk factor for stroke in Italy.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Trastornos Cerebrovasculares/etiología , Adulto , Anciano , Anciano de 80 o más Años , Consumo de Bebidas Alcohólicas/sangre , Alcoholismo/sangre , Alcoholismo/complicaciones , Aspartato Aminotransferasas/sangre , Biomarcadores/sangre , Isquemia Encefálica/sangre , Isquemia Encefálica/etiología , Estudios de Casos y Controles , Hemorragia Cerebral/sangre , Hemorragia Cerebral/etiología , Trastornos Cerebrovasculares/sangre , Complicaciones de la Diabetes , Índices de Eritrocitos , Femenino , Humanos , Hipertensión/complicaciones , Italia , Masculino , Persona de Mediana Edad , Factores de Riesgo , Fumar/efectos adversos , Ácido Úrico/sangre , gamma-Glutamiltransferasa/sangre
16.
Thromb Res ; 78(4): 277-82, 1995 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-7631308

RESUMEN

The vasoactive peptide bradykinin may be involved in the pathogenesis of vasodilation, which has been considered the initiating event of ascites formation in cirrhotic patents. Since bradykinin is generated through the cleavage of high molecular weight kininogen (HK) by kallikrein, we looked for the cleavage of HK by an immunoblotting technique in plasma and ascitic fluid of 28 patients with cirrhosis of different etiology. The majority of patients showed massive cleavage of HK in ascitic fluid (median 50% of total HK; range 23-100%). Patients with severe ascites had more cleaved HK in plasma (29%; range 8-38%) than normal subjects (22%; range 11-32) (P = 0.02). Patients with high levels of plasma renin activity (5-60 ng/ml/hour), which is considered a consequence of peripheral vasodilation, had more plasma cleaved HK (31%; range 18-38)(p = 0.0097) than normals. Thus, our data support the view that cleavage of HK could play a role in the pathogenesis of vasodilation and ascites formation in patients with decompensated cirrhosis.


Asunto(s)
Ascitis/metabolismo , Quininógenos/metabolismo , Cirrosis Hepática/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Quininógenos/sangre , Masculino , Persona de Mediana Edad , Renina/sangre , Vasodilatación
17.
Ital J Neurol Sci ; 13(3): 209-14, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1624276

RESUMEN

The role of alcohol as a risk factor for cerebral infarction and hemorrhage has been assesed in 200 middle-aged and elderly stroke patients and 200 controls matched for age, sex and hospital admission date. Computed tomographic brain scans were done in all but 10 of the stroke patients. Alcohol intake was reckoned on the 12 months preceding hospitalization and expressed in grams daily according to a standard nomogram. The Michigan Alcoholism Screening Test was used for the diagnosis of alcoholism. Cerebral infarction was present in 59% of the stroke patients and cerebral hemorrhage in 9%. The role of alcohol as risk factor for stroke proved to be small (Odds Ratio 1.86) and was practically lost after adjustment for the most common risk factors for cerebrovascular disorders (previous strokes, arterial hypertension, diabetes, obesity and hyperlipidemia). Our findings seem to suggest that alcohol is not an independent risk factor for stroke in the middle-aged and elderly. The data are, however, preliminary and are discussed in the light of methological problems.


Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Alcoholismo/complicaciones , Trastornos Cerebrovasculares/etiología , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo
18.
Eur J Epidemiol ; 7(4): 320-7, 1991 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1915783

RESUMEN

Risk factors for pneumonia were analysed in a large population of critically ill patients, collected in two prospective multicentre "pneumonia studies" in Italy. Twenty-three intensive care units were involved and the study time was 150 unit months. Only patients without previous pulmonary infection, with intensive care unit stay greater than or equal to 48 hours and no rapidly irreversible illness at admission were included. The incidence of pneumonia in the 1475 selected patients was 15% (220 cases). 239 patients died in ICU; the mortality rate was significantly higher in patients developing pneumonia (p less than 0.0001); pneumonia was found to be an independent highly significant risk factor for death in critically ill patients (OR = 3.88; p less than 0.0001). Multivariate analysis of seven risk factors for pneumonia showed a significantly higher risk in patients with neuromuscular disease (OR = 3.8, p less than 0.002), impairment of airway reflexes at admission (OR = 2.93, p less than 0.0001), and greater than or equal to 24h respiratory assistance (OR = 3.05, p less than 0.0001). Impairment of airway reflexes at admission to the emergency room or intensive care unit identifies the population who will experience 3/4 of the overall lower respiratory tract infections. Rapid recognition of at-risk patients seems clinically important and may improve awareness programs and preventive approaches.


Asunto(s)
Cuidados Críticos , Neumonía/epidemiología , Enfermedad Aguda , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Lactante , Unidades de Cuidados Intensivos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Neumonía/etiología , Neumonía/mortalidad , Estudios Prospectivos , Infecciones del Sistema Respiratorio/complicaciones , Factores de Riesgo
19.
Am Rev Respir Dis ; 140(2): 302-5, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2764365

RESUMEN

In 724 critically ill patients who had received prolonged (greater than 24 h) ventilatory assistance since admission to the ward, we analyzed the relationship between artificial ventilatory support and pulmonary infection. Two different approaches were used. The first, plotting the incidence of pneumonia versus the duration of ventilatory support, confirms previous data: the incidence rises from 5% in patients receiving one day of respiratory assistance to 68.8% in patients receiving more than 30 days. In the second approach, the same data were computed as an actuarial life table with the day of pneumonia onset as terminal event. This different approach, focusing on the onset of infection rather than on incidence, allows a new insight into the problem of nosocomial infection: pneumonia in patients with respiratory support is an early occurrence with a high and constant rate of acquisition and, therefore, a high risk of infection in the first eight to ten days. Later pneumonia acquisitions were rare, and the risk after ten days of ventilatory support is low.


Asunto(s)
Cuidados Críticos , Neumonía/etiología , Respiración Artificial/efectos adversos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Riesgo , Factores de Tiempo
20.
Crit Care Med ; 17(6): 501-5, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2656096

RESUMEN

In a randomized multicenter clinical trial on antibiotic prophylaxis, 1,319 patients in 23 ICUs were enrolled over a 4-month period. The end-point of the study was the prevention of early onset pneumonia (EOP), defined as acquired pneumonia diagnosed within 4 days of ICU admission; this accounted for greater than 50% of overall pneumonia. Patients eligible for the study were divided into three groups which received either cefoxitin (2 g iv for three doses/8 h), penicillin G (2 million U iv for four doses/6 h), or no antibiotic (control group). In the overall population, the incidence of EOP was 6.1% in the prophylaxis recipients vs. 7.2% in the control group (a 15.3% reduction). No statistically different rates of pneumonia or death were found among the groups. Patients with impaired reflexes on admission or prolonged ventilatory support were noted to have a lower incidence of EOP and an improved outcome when treated with cefoxitin.


Asunto(s)
Cefoxitina/uso terapéutico , Unidades de Cuidados Intensivos , Penicilina G/uso terapéutico , Neumonía/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Ensayos Clínicos como Asunto , Infección Hospitalaria/prevención & control , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Premedicación , Distribución Aleatoria
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