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1.
AJNR Am J Neuroradiol ; 42(3): 610-615, 2021 03.
Article in English | MEDLINE | ID: mdl-33478946

ABSTRACT

BACKGROUND AND PURPOSE: Spinal cord damage is a hallmark of hereditary spastic paraplegias, but it is still not clear whether specific subtypes of the disease have distinctive patterns of spinal cord gray (GM) and white (WM) matter involvement. We compared cervical cross-sectional GM and WM areas in patients with distinct hereditary spastic paraplegia subtypes. We also assessed whether these metrics correlated with clinical parameters. MATERIALS AND METHODS: We analyzed 37 patients (17 men; mean age, 47.3 [SD, 16.5] years) and 21 healthy controls (7 men; mean age, 42.3 [SD, 13.2] years). There were 7 patients with spastic paraplegia type 3A (SPG3A), 12 with SPG4, 10 with SPG7, and 8 with SPG11. Image acquisition was performed on a 3T MR imaging scanner, and T2*-weighted 2D images were assessed by the Spinal Cord Toolbox. Statistical analyses were performed in SPSS using nonparametric tests and false discovery rate-corrected P values < .05. RESULTS: The mean disease duration for the hereditary spastic paraplegia group was 22.4 [SD, 13.8] years and the mean Spastic Paraplegia Rating Scale score was 22.8 [SD, 11.0]. We failed to identify spinal cord atrophy in SPG3A and SPG7. In contrast, we found abnormalities in patients with SPG4 and SPG11. Both subtypes had spinal cord GM and WM atrophy. SPG4 showed a strong inverse correlation between GM area and disease duration (ρ = -0.903, P < .001). CONCLUSIONS: Cervical spinal cord atrophy is found in some but not all hereditary spastic paraplegia subtypes. Spinal cord damage in SPG4 and 11 involves both GM and WM.


Subject(s)
Gray Matter/pathology , Spastic Paraplegia, Hereditary/pathology , Spinal Cord/pathology , White Matter/pathology , Adult , Cross-Sectional Studies , Female , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged
2.
Eur J Neurol ; 27(10): 2072-2078, 2020 10.
Article in English | MEDLINE | ID: mdl-32441838

ABSTRACT

BACKGROUND AND PURPOSE: Neurological manifestations have been identified in the context of autoimmune hepatitis (AIH). Previous case reports highlighted the association between AIH and sensory neuronopathy (SN). Despite that, little is known about the frequency of AIH-related SN and its clinical/neurophysiological profile. Moreover, it is not clear whether SN is an AIH-specific manifestation or related to chronic liver damage. METHODS: Seventy consecutive AIH patients were enrolled and their characteristics were compared with 52 consecutive patients with chronic active hepatitis B. All subjects underwent clinical and neurophysiological evaluation. Further comparisons were performed between AIH SN and AIH non-SN patients. RESULTS: Mean ages and male:female proportions in the AIH and chronic active hepatitis B groups were 42.2 ± 16.3/51.7 ± 13.6 years and 14:56/29:23, respectively. The frequencies of carpal tunnel syndrome, radiculopathy and polyneuropathy were similar between groups. In contrast, SN was identified only in AIH patients (5/70 vs. 0/52, P = 0.04); the overall prevalence of AIH-related SN was 7% with an average profile of a woman in her 40s with asymmetric onset of sensory deficits that chronically evolved to disabling proprioceptive ataxia associated with marked dysautonomia. Neurological disability and hepatocellular damage did not follow in parallel. Anti-fibroblast growth factor receptor type 3 antibodies were found in 3/5 (60%) of the patients with AIH-related SN. Clinical or demographic predictors of SN in the context of AIH could not be identified. CONCLUSION: Sensory neuronopathy, but not other peripheral nervous system diseases, is a specific AIH neurological manifestation. It is often disabling and, in contrast to hepatocellular injury, does not respond to immunosuppression.


Subject(s)
Hepatitis, Autoimmune , Liver Diseases , Peripheral Nervous System Diseases , Adult , Aged , Female , Hepatitis, Autoimmune/complications , Humans , Male , Middle Aged , Peripheral Nervous System Diseases/epidemiology , Peripheral Nervous System Diseases/etiology
3.
Eur J Neurol ; 26(3): 483-489, 2019 03.
Article in English | MEDLINE | ID: mdl-30326180

ABSTRACT

BACKGROUND AND PURPOSE: Friedreich's ataxia (FRDA) is the most common autosomal-recessive ataxia worldwide. It is characterized by early onset, sensory abnormalities and slowly progressive ataxia. All magnetic resonance imaging (MRI)-based studies have focused on the evaluation of adult patients. Therefore, we designed a cross-sectional multimodal MRI-based study to investigate the anatomical substrates involved in the early stages of FRDA. METHODS: We enrolled 37 patients (12 children) and 38 controls. All subjects underwent MRI in a 3T device to assess gray and white matter. We used measures from FreeSurfer and CERES to evaluate the cerebral and cerebellar cortices. The T1 multiatlas assessed deep gray matter. The diffusion tensor imaging multiatlas was used to investigate microstructural abnormalities in brain white matter and SpineSeg was used to assess the cervical spinal cord. All analyses were corrected for multiple comparisons. RESULTS: Comparison with age-matched controls showed that pediatric patients have spinal cord, inferior cerebellar peduncle and red nucleus damage. In contrast, adult patients showed more widespread white matter damage than pediatric patients. With regard to gray matter, we found cortical thinning at the left central sulcus and volumetric reduction in the thalami and hippocampi only in adult patients. Finally, values of fractional anisotropy in adult patients and radial diffusivity in pediatric patients from the inferior cerebellar peduncle correlated with disease duration and ataxia severity, respectively. CONCLUSIONS: Structural damage in FRDA begins in the spinal cord and inferior cerebellar peduncle as well as the red nucleus, and progresses to cerebral areas in adulthood. These results shed some light on the early stages of FRDA and highlight potential neuroimaging markers for therapeutic trials.


Subject(s)
Friedreich Ataxia , Gray Matter , White Matter , Adolescent , Adult , Aged , Child , Cross-Sectional Studies , Female , Friedreich Ataxia/diagnostic imaging , Friedreich Ataxia/pathology , Gray Matter/diagnostic imaging , Gray Matter/pathology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , White Matter/diagnostic imaging , White Matter/pathology , Young Adult
4.
J Chem Phys ; 147(17): 174704, 2017 Nov 07.
Article in English | MEDLINE | ID: mdl-29117701

ABSTRACT

Layered clay materials have been used to incorporate transition metal (TM) contaminants. Based on first-principles calculations, we have examined the energetic stability and the electronic properties due to the incorporation of Cd and Hg in layered clay materials, kaolinite (KAO) and pyrophyllite (PYR). The TM can be (i) adsorbed on the clay surface as well as (ii) intercalated between the clay layers. For the intercalated case, the contaminant incorporation rate can be optimized by controlling the interlayer spacing of the clay, namely, pillared clays. Our total energy results reveal that the incorporation of the TMs can be maximized through a suitable tuning of vertical distance between the clay layers. Based on the calculated TM/clay binding energies and the Langmuir absorption model, we estimate the concentrations of the TMs. Further kinetic properties have been examined by calculating the activation energies, where we found energy barriers of ∼20 and ∼130 meV for adsorbed and intercalated cases, respectively. The adsorption and intercalation of ionized TM adatoms were also considered within the deprotonated KAO surface. This also leads to an optimal interlayer distance which maximizes the TM incorporation rate. By mapping the total charge transfers at the TM/clay interface, we identify a net electronic charge transfer from the TM adatoms to the topmost clay surface layer. The effect of such a charge transfer on the electronic structure of the clay (host) has been examined through a set of X-ray absorption near edge structure (XANES) simulations, characterizing the changes of the XANES spectra upon the presence of the contaminants. Finally, for the pillared clays, we quantify the Cd and Hg K-edge energy shifts of the TMs as a function of the interlayer distance between the clay layers and the Al K-edge spectra for the pristine and pillared clays.

5.
Ann Epidemiol ; 3(1): 64-70, 1993 Jan.
Article in English | MEDLINE | ID: mdl-8287158

ABSTRACT

This study investigated social class differentials in cancer mortality in São Paulo county, Brazil, for the period 1978 to 1982. A measure of socioeconomic status based on education was used, and cancer risk by level of education was estimated by a case-control approach in which other cancers were considered as controls. For most cancers, the socioeconomic differences in risk were similar to those found in western Europe and North America. For lung cancer, however, the highest risk was observed in men and women with the most education. Other cancers related to tobacco--cancer of the larynx, pharynx, and esophagus--showed a negative association with education. The differences between social classes in consumption habits of alcohol and maté and the use of black tobacco are probably responsible for these contrasting patterns. For breast and cervix uteri cancer the social class patterns were similar to those found in developed countries--a positive relationship for breast and a negative one for cervix uteri cancer. The magnitude of the differences observed between social classes for these cancers was frequently greater in South America than in the United States or western Europe.


Subject(s)
Educational Status , Neoplasms/mortality , Adult , Brazil/epidemiology , Case-Control Studies , Europe/epidemiology , Female , Humans , Male , Middle Aged , Risk Factors , Social Class , United States/epidemiology
6.
Rev Saude Publica ; 24(1): 11-9, 1990 Feb.
Article in English | MEDLINE | ID: mdl-2218371

ABSTRACT

The nutritional status according to anthropometric data was assessed in 756 schoolchildren from 5 low-income state schools and in one private school in the same part of Rio de Janeiro, Brazil. The prevalence of stunting and wasting (cut-off point: less than 90% ht/age and less than 80% wt/ht) ranged in the public schools from 6.2 to 15.2% and 3.3 to 24.0%, respectively, whereas the figures for the private school were 2.3 and 3.5%, respectively. Much more obesity was found in the private school (18.0%) than in the state schools (0.8-6.2%). Nutritional problems seem to develop more severely in accordance with the increasing age of the children. Therefore it appears advisable to assess schoolchildren within the context of nutritional surveillance system.


Subject(s)
Anthropometry , Nutritional Status , Adolescent , Age Factors , Body Height , Body Weight , Brazil , Child , Educational Status , Female , Humans , Male , Sex Factors , Socioeconomic Factors
7.
Hansenol Int ; 12(2): 21-8, 1987 Dec.
Article in Portuguese | MEDLINE | ID: mdl-3271231

ABSTRACT

The evaluation of the physical disabilities at the moment of the hanseniasis diagnosis was carried out through the clinical and epidemiological forms of the 8,915 cases recorded in the State of São Paulo, Brazil, from 1981 to 1983. The records of the physical disabilities were studied by three different methods: the disabilities at their highest grade, the disabilities' grade index achieved from the arithmetic mean of the added values of the different disability grades, and the absolute disabilities frequency. The study suggested that the maximum grade was the best evaluation method of the physical disabilities at the moment of the diagnosis, being an important indicator for the evaluation of prevention efforts and of the hanseniasis control.


Subject(s)
Disability Evaluation , Leprosy/epidemiology , Adolescent , Adult , Analysis of Variance , Brazil/epidemiology , Child , Child, Preschool , Eye/pathology , Female , Foot/pathology , Hand/pathology , Humans , Incidence , Infant , Leprosy/complications , Male , Middle Aged , Retrospective Studies
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