Lack of association between the brain-derived neurotrophin factor (C-270T) polymorphism and late-onset Alzheimer's disease (LOAD) in Brazilian patients.

After the identification of the apolipoprotein E gene isoform (APOE-epsilon4) as a risk factor for late-onset Alzheimer's disease (LOAD), the search for other polymorphisms associated with AD has been undertaken by many groups of investigators around the world. These studies have shown controversial results in many populations. More recently, a single nucleotide polymorphism in the promoter region of the brain-derived neurotrophin factor (BDNF) was found to be a risk factor for AD in two independent population studies.

Analysis of IL-1alpha, IL-1beta, and IL-1RA [correction of IL-RA] polymorphisms in dysthymia.

Investigators of independent studies reported alterations in cytokine serum levels in patients with different mood disorders. Several polymorphisms associated with neuropsychiatric disorders such as schizophrenia and Alzheimer's disease have been reported at the interleukin-1 (IL-1) panel. Here we report the results of three specific polymorphisms at the IL-1alpha, IL-1beta, and IL-1RA genes, which were analyzed in 128 Brazilian subjects: 59 dysthymic patients and 69 normal controls.

Asymptomatic carriers and gender differences in facioscapulohumeral muscular dystrophy (FSHD).

Facioscapulohumeral muscular dystrophy is an autosomal dominant muscle disorder, mapped to 4q35. It is characterized by remarkable inter- and intrafamilial clinical variability ranging from severe phenotype to asymptomatic carriers. The aim of the present study was to assess the size of the Eco RI fragment in a large sample of asymptomatic or minimally affected carriers as well as symptomatic patients, comparing both sexes, in order to verify if asymptomatic carriers are randomly distributed or concentrated in some particular families and if there is preferential parental transmission (maternal or paternal) resulting in non-penetrant carriers.

Asymptomatic carriers for homozygous novel mutations in the FKRP gene: the other end of the spectrum.

Autosomal recessive limb-girdle muscular dystrophy linked to 19q13.3 (LGMD2I) was recently related to mutations in the fukutin-related protein gene (FKRP) gene. Pathogenic changes in the same gene were detected in congenital muscular dystrophy patients (MDC1C), a severe disorder.

Calpainopathy: how broad is the spectrum of clinical variability?

Five affected siblings were referred with a probable diagnosis of proximal adult-type spinal muscular atrophy (SMA) based on lower motor neuron signs (muscle weakness and atrophy, hypotony, hypoactive or absent reflexes, and fasciculations), normal or borderline serum creatine kinase levels, and a neurogenic pattern on electromyography, compatible with motor neuron disease, in one patient. No exon 7-8 deletion in the survival motor neuron (SMN) gene was found. Linkage analysis excluded the SMN and all known autosomal recessive limb girdle muscular dystrophy loci, with the exception of LGMD-2A.

Are changes in MAPK/ERK necessary or sufficient for entrainment in chick pineal cells?

Chick pineal cells in culture display a circadian rhythm of melatonin release. Light pulses can entrain (phase shift) the rhythm. One candidate for the photoentrainment pathway uses a mitogen-activated protein kinase (MAPK), also known as extracellular signal-regulated kinase (ERK).

CFTR, PRSS1 and SPINK1 mutations in the development of pancreatitis in Brazilian patients.

Context: Mutations in cystic fibrosis transmembrane conductance regulator (CFTR), in cationic trypsinogen (PRSS1) and in serine protease inhibitor Kazal type 1 (SPINK1) genes have been associated with chronic pancreatitis (alcohol related, idiopathic and hereditary). However, the inheritance pattern is still not clear.

Patients: Eighty-two unrelated Brazilian patients with chronic pancreatitis (alcohol-related disease in 64, idiopathic disease in 16, and hereditary disease in 2).

The 10 autosomal recessive limb-girdle muscular dystrophies.

Fifteen forms of limb-girdle muscular dystrophies (5 autosomal dominant and 10 autosomal recessive) have already been found. The 10 genes responsible for the autosomal recessive forms, which account for more than 90% of the cases, had their product identified. This review will focus on the most recent data on autosomal recessive-limb-girdle muscular dystrophy and on our own experience of more than 300 patients studied from 120 families who were classified (based on DNA, linkage and muscle protein analysis) in eight different forms of autosomal recessive-limb-girdle muscular dystrophy.

The effect of calpain 3 deficiency on the pattern of muscle degeneration in the earliest stages of LGMD2A.

Limb girdle muscular dystrophy type 2A (LGMD2A) is caused by mutations in the calpain 3 gene. In a large family affected by LGMD2A with four severely affected members, three additional asymptomatic relatives had very high serum creatine kinase concentrations. All were homozygous for the R110X mutation and showed a total absence of calpain 3 in the muscle.

Rod distribution and muscle fiber type modification in the progression of nemaline myopathy.

Nemaline myopathy is a structural congenital myopathy associated with the presence of rodlike structures inside the muscle fibers and type I predominance. It may be caused by mutations in at least five genes: slow alpha-tropomyosin 3 (chromosome 1q22-23), nebulin (chromosome 2q21.1-q22), actin (chromosome 1q42), tropomyosin 2 (chromosome 9p13), and troponin T1 (chromosome 19q13.

Protein defects in neuromuscular diseases.

Muscular dystrophies are a heterogeneous group of genetically determined progressive disorders of the muscle with a primary or predominant involvement of the pelvic or shoulder girdle musculature. The clinical course is highly variable, ranging from severe congenital forms with rapid progression to milder forms with later onset and a slower course. In recent years, several proteins from the sarcolemmal muscle membrane (dystrophin, sarcoglycans, dysferlin, caveolin-3), from the extracellular matrix (alpha2-laminin, collagen VI), from the sarcomere (telethonin, myotilin, titin, nebulin), from the muscle cytosol (calpain 3, TRIM32), from the nucleus (emerin, lamin A/C, survival motor neuron protein), and from the glycosylation pathway (fukutin, fukutin-related protein) have been identified.

Deficiency of muscle alpha-actinin-3 is compatible with high muscle performance.

Long-distance runners generally have a remarkably high proportion of slow type I fibers in their lower muscle groups. However, the transformation of type II fast fibers to slow type I fibers as a result of exercise has not been demonstrated clearly. We report the analysis of muscle type composition on m.

Bioinformatics training in the USA.

This paper provides an overview of the history and funding of bioinformatics training in the USA, and summarises some of the challenges and key features associated with bioinformatics training programmes at PhD level. The paper includes compilations of current PhD bioinformatics training programmes and sources of funding.

Clinical variability in calpainopathy: what makes the difference?

Limb girdle muscular dystrophies (LGMD) are a heterogeneous group of genetic disorders characterised by progressive weakness of the pelvic and shoulder girdle muscles and a great variability in clinical course. LGMD2A, the most prevalent form of LGMD, is caused by mutations in the calpain-3 gene (CAPN-3). More than 100 pathogenic mutations have been identified to date, however few genotype : phenotype correlation studies, including both DNA and protein analysis, have been reported.

Telethonin protein expression in neuromuscular disorders.

Telethonin is a 19-kDa sarcomeric protein, localized to the Z-disc of skeletal and cardiac muscles. Mutations in the telethonin gene cause limb-girdle muscular dystrophy type 2G (LGMD2G). We investigated the sarcomeric integrity of muscle fibers in LGMD2G patients, through double immunofluorescence analysis for telethonin with three sarcomeric proteins: titin, alpha-actinin-2, and myotilin and observed the typical cross striation pattern, suggesting that the Z-line of the sarcomere is apparently preserved, despite the absence of telethonin.

Further evidence for a fourth gene causing X-linked pure spastic paraplegia.

X-linked hereditary spastic paraplegias (HSPs) present with two distinct phenotypes: pure and complicated. The pure form is characterized by slowly progressive weakness and spasticity of the lower limbs, whereas the complicated forms have additional features (optic neuropathy, retinopathy, extrapyramidal disturbance, dementia, epilepsy, ataxia, ichthyosis, mental retardation, and deafness). Three X-linked loci have been identified for the complicated HSP, while mutations in the proteolipid gene (PLP) (locus SPG2) were implicated in both pure and complicated forms.