213 research outputs found
Variants Cause Spastic Paraplegia Associated with Cerebral Hypomyelination
Oculodentodigital dysplasia is an autosomal dominant disorder due to variants characterized by dysmorphic features. Neurologic symptoms have been described in some patients but without a clear neuroimaging pattern. To understand the pathophysiology underlying neurologic deficits in oculodentodigital dysplasia, we studied 8 consecutive patients presenting with hereditary spastic paraplegia due to variants. Clinical disease severity was highly variable. Cerebral MR imaging revealed variable white matter abnormalities, consistent with a hypomyelination pattern, and bilateral hypointense signal of the basal ganglia on T2-weighted images and/or magnetic susceptibility sequences, as seen in neurodegeneration with brain iron accumulation diseases. Patients with the more prominent basal ganglia abnormalities were the most disabled ones. This study suggests that -related hereditary spastic paraplegia is a complex neurodegenerative disease affecting both the myelin and the basal ganglia. variants should be considered in patients with hereditary spastic paraplegia presenting with brain hypomyelination, especially if associated with neurodegeneration and a brain iron accumulation pattern
The Frequencies of Different Inborn Errors of Metabolism in Adult Metabolic Centres: Report from the SSIEM Adult Metabolic Physicians Group
There are few centres which specialise in the care of adults with inborn errors of metabolism (IEM). To anticipate facilities and staffing needed at these centres, it is of interest to know the distribution of the different disorders
Hydrodynamics of Spatially Ordered Superfluids
We derive the hydrodynamic equations for the supersolid and superhexatic
phases of a neutral two-dimensional Bose fluid. We find, assuming that the
normal part of the fluid is clamped to an underlying substrate, that both
phases can sustain third-sound modes and that in the supersolid phase there are
additional modes due to the superfluid motion of point defects (vacancies and
interstitials).Comment: 24 pages of ReVTeX and 7 uuencoded figures. Submitted for publication
in Phys. Rev.
Resposta de brachiaria Dictyoneura à níveis de fósforo.
Neste trabalho avaliaram-se os efeitos da fertilização fosfatada sobre a produção de forragem e composição química de Brachiaria dictyoneura..
Onset of Superfluidity in 4He Films Adsorbed on Disordered Substrates
We have studied 4He films adsorbed in two porous glasses, aerogel and Vycor,
using high precision torsional oscillator and DC calorimetry techniques. Our
investigation focused on the onset of superfluidity at low temperatures as the
4He coverage is increased. Torsional oscillator measurements of the 4He-aerogel
system were used to determine the superfluid density of films with transition
temperatures as low as 20 mK. Heat capacity measurements of the 4He-Vycor
system probed the excitation spectrum of both non-superfluid and superfluid
films for temperatures down to 10 mK. Both sets of measurements suggest that
the critical coverage for the onset of superfluidity corresponds to a mobility
edge in the chemical potential, so that the onset transition is the bosonic
analog of a superconductor-insulator transition. The superfluid density
measurements, however, are not in agreement with the scaling theory of an onset
transition from a gapless, Bose glass phase to a superfluid. The heat capacity
measurements show that the non-superfluid phase is better characterized as an
insulator with a gap.Comment: 15 pages (RevTex), 21 figures (postscript
A study of molecular changes relating to energy metabolism and cellular stress in people with Huntington’s disease: looking for biomarkers
A randomized trial assessing the safety, pharmacokinetics, and efficacy during morning off of AZ-009
Stress-related psychiatric disorders across the life spa
Fatores associados à inadequação do uso da assistência pré-natal
OBJECTIVE: To identify factors associated with inadequacy of prenatal care utilization in urban community. METHODS: A cross-sectional study of a systematic sample stratified by maternity hospital, consisting of hospital births in the municipality of São Luís, Brazil, was carried out from March 1997 to February 1998. Socioeconomic and demographic factors, reproductive health, morbidity during pregnancy, and utilization of prenatal care services were studied. Mothers answered a standardized questionnaire before hospital discharge. The adequacy of prenatal care utilization was analyzed by means of two indexes: APNCU (Adequacy of Prenatal Care Utilization) and a new index based on the recommendations of the Brazilian Ministry of Health. RESULTS: There were interviewed 2,831 women who delivered at 10 public and private maternity hospitals. The inadequacy of prenatal care utilization was 49.2% according to the APNCU index and 24.5% when determined by the Brazilian index. Prenatal care at public services, low maternal schooling, low income, having no partner, and absence of maternal diseases during pregnancy were associated with inadequacy of prenatal care use according to both indexes. High parity and maternal age of 35 years or more were also associated with inadequacy, whereas primiparity, morbidity, and young maternal age (OBJETIVO: Identificar fatores associados à inadequação do uso da assistência pré-natal em comunidade urbana. MÉTODOS: Foi realizado estudo transversal em amostra sistemática, estratificada por maternidades, de todos os nascimentos hospitalares do município de São Luís, MA, no período de março de 1997 a fevereiro de 1998. Foram avaliados indicadores socioeconômicos e demográficos, de saúde reprodutiva, morbidade na gravidez e utilização de serviços pré-natais. Utilizou-se questionário padronizado respondido pelas puérperas antes da alta hospitalar. A adequação do uso da assistência pré-natal foi analisada pelo índice "Adequacy of Prenatal Care Utilization" (APNCU) e por um novo índice proposto, baseado nas recomendações do Ministério da Saúde, Brasil. RESULTADOS: Foram entrevistadas 2.831 puérperas, atendidas em dez unidades de saúde pública e privada. A inadequação do uso da assistência pré-natal foi de 49,2% pelo índice APNCU, e de 24,5% pelo novo índice proposto. Mulheres atendidas em serviços públicos de saúde, de baixa escolaridade e baixa renda familiar, sem companheiro ou com doença durante a gravidez, tiveram maiores percentuais de inadequação do uso do atendimento pré-natal, pelos dois índices analisados. Pelo novo índice proposto, maiores percentuais de inadequação foram associados à alta paridade e idade materna, enquanto baixa idade materna
Loss of paraplegin drives spasticity rather than ataxia in a cohort of 241 patients with SPG7
Objective : We took advantage of a large multinational recruitment to delineate genotype-phenotype correlations in a large, trans-European multicenter cohort of patients with spastic paraplegia gene 7 (SPG7).
Methods : We analyzed clinical and genetic data from 241 patients with SPG7, integrating neurologic follow-up data. One case was examined neuropathologically.
Results : Patients with SPG7 had a mean age of 35.5 +/- 14.3 years (n = 233) at onset and presented with spasticity (n = 89), ataxia (n = 74), or both (n = 45). At the first visit, patients with a longer disease duration (> 20 years, n = 62) showed more cerebellar dysarthria (p < 0.05), deep sensory loss (p < 0.01), muscle wasting (p < 0.01), ophthalmoplegia (p < 0.05), and sphincter dysfunction (p < 0.05) than those with a shorter duration (< 10 years, n = 93). Progression, measured by Scale for the Assessment and Rating of Ataxia evaluations, showed a mean annual increase of 1.0 +/- 1.4 points in a subgroup of 30 patients. Patients homozygous for loss of function (LOF) variants (n = 65) presented significantly more often with pyramidal signs (p < 0.05), diminished visual acuity due to optic atrophy (p < 0.0001), and deep sensory loss (p < 0.0001) than those with at least 1 missense variant (n = 176). Patients with at least 1 Ala510Val variant (58%) were older (age 37.6 +/- 13.7 vs 32.8 +/- 14.6 years, p < 0.05) and showed ataxia at onset (p < 0.05). Neuropathologic examination revealed reduction of the pyramidal tract in the medulla oblongata and moderate loss of Purkinje cells and substantia nigra neurons.
Conclusions : This is the largest SPG7 cohort study to date and shows a spasticity-predominant phenotype of LOF variants and more frequent cerebellar ataxia and later onset in patients carrying at least 1 Ala510Val variant
Opportunities for mesoscopics in thermometry and refrigeration: Physics and applications
This review presents an overview of the thermal properties of mesoscopic
structures. The discussion is based on the concept of electron energy
distribution, and, in particular, on controlling and probing it. The
temperature of an electron gas is determined by this distribution:
refrigeration is equivalent to narrowing it, and thermometry is probing its
convolution with a function characterizing the measuring device. Temperature
exists, strictly speaking, only in quasiequilibrium in which the distribution
follows the Fermi-Dirac form. Interesting nonequilibrium deviations can occur
due to slow relaxation rates of the electrons, e.g., among themselves or with
lattice phonons. Observation and applications of nonequilibrium phenomena are
also discussed. The focus in this paper is at low temperatures, primarily below
4 K, where physical phenomena on mesoscopic scales and hybrid combinations of
various types of materials, e.g., superconductors, normal metals, insulators,
and doped semiconductors, open up a rich variety of device concepts. This
review starts with an introduction to theoretical concepts and experimental
results on thermal properties of mesoscopic structures. Then thermometry and
refrigeration are examined with an emphasis on experiments. An immediate
application of solid-state refrigeration and thermometry is in ultrasensitive
radiation detection, which is discussed in depth. This review concludes with a
summary of pertinent fabrication methods of presented devices.Comment: Close to the version published in RMP; 59 pages, 35 figure
- …