Abnormal motor unit synchronization of antagonist muscles underlies pathological co-contraction in upper limb dystonia.

The aim of this study was to examine the pathophysiological mechanisms underlying co-contraction in patients with dystonia (n = 6) and writer's cramp (n = 5). Multi-unit needle and surface EMGs were recorded from extensor carpi radialis (ECR) and flexor carpi radialis (FCR) muscles during motor tasks that elicited dystonia or writer's cramp. The EMGs from ECR and FCR were recorded simultaneously and analysed using cross-correlation analysis.

Using electroencephalography to study functional coupling between cortical activity and electromyograms during voluntary contractions in humans.

Previous studies of neuronal oscillations in sensorimotor cortex in humans and primates have observed rhythmic 15-30 Hz activity, which is correlated with motor output. In humans, this work has been limited to magnetic recordings. In the present study we investigate if similar results can be obtained using electroencephalography (EEG).

Effect of insoluble extracellular matrix molecules on Fas expression in epithelial cells.

Fas, which functions to initiate a signal causing apoptosis, is expressed in epithelia, thus, suggesting a role in controlling cell number during states of cell and matrix turnover. In view of this, we hypothesized that cell-matrix interactions may be an important determinant of Fas expression in epithelial cells. To investigate this, we examined the effect of insoluble extracellular matrix molecules on Fas expression in murine lung epithelial (MLE) cells, a transformed mouse lung epithelial cell line.

PPARgamma induces the insulin-dependent glucose transporter GLUT4 in the absence of C/EBPalpha during the conversion of 3T3 fibroblasts into adipocytes.

To define the molecular mechanisms that control GLUT4 expression during adipogenesis, NIH-3T3 fibroblasts ectopically expressing different adipogenic transcription factors (C/EBPbeta, C/EBPdelta, C/EBPalpha, and PPARgamma) under the control of a tetracycline-responsive inducible (C/EBPs) or a constitutive retroviral (PPARgamma) expression system were used. Enhanced production of C/EBPbeta (beta2 cell line), C/EBPbeta together with C/EBPdelta (beta/delta39 cell line), C/EBPalpha (alpha1 cell line), or PPARgamma (Pgamma2 cell line) in cells exposed to dexamethasone and the PPARgamma ligand ciglitazone (a thiazolidinedione) resulted in expression of GLUT4 mRNA as well as other members of the adipogenic gene program, including aP2 and adipsin. Focusing our studies on the beta/delta39 cells, we have demonstrated that C/EBPbeta along with C/EBPdelta in the presence of dexamethasone induces PPARgamma, adipsin, and aP2 mRNA production; however, GLUT4 mRNA is only expressed in cells exposed to ciglitazone.

Improvement in gait parameters following late intervention in traumatic brain injury: a long-term follow-up report of a single case.

Objective: To evaluate the effect of using an optimally adjusted fixed ankle foot orthosis to control knee pain and promote improvement in gait parameters in a subject with hemiplegia following a traumatic brain injury 11 years previously.

Design: This is the report of a single case, using gait laboratory facilities to monitor force alignment relative to the knee and single leg balance time with the subject barefoot.

Subject: A 35-year-old woman with a right hemiplegia seen 11 years after onset.

A review of 42 patients of 16 years and over using the ORLAU Parawalker.

A 7 year retrospective review of 42 patients of 16 years or over using the ORLAU Parawalker has been conducted to establish the degree of long-term compliance in using the orthosis on a regular basis. Regular use was defined as putting the orthosis on at least once a week. All subjects had been supplied with an ORLAU Parawalker via the routine supply procedures adopted in Oswestry, and were followed up at regular 6 month intervals as part of the standard treatment regime.

A review of recent applications of cross-correlation methodologies to human motor unit recording.

This article reviews some recent applications of time and frequency domain cross-correlation techniques to human motor unit recording. These techniques may be used to examine the pre-synaptic mechanisms involved in control of motoneuron activity during on-going motor tasks in man without the need for imposed and artificial perturbations of the system. In this review we examine, through several examples, areas in which insights have been gained into the basic neurophysiological processes that bring about motoneuron firing in man and illustrate how these processes are affected by central nervous system pathology.

Interleukin-5 expression in the lung epithelium of transgenic mice leads to pulmonary changes pathognomonic of asthma.

We have generated transgenic mice that constitutively express murine interleukin (IL)-5 in the lung epithelium. Airway expression of this cytokine resulted in a dramatic accumulation of peribronchial eosinophils and striking pathologic changes including the expansion of bronchus-associated lymphoid tissue (BALT), goblet cell hyperplasia, epithelial hypertrophy, and focal collagen deposition. These changes were also accompanied by eosinophil infiltration of the airway lumen.

The single MyoD family gene of Ciona intestinalis encodes two differentially expressed proteins: implications for the evolution of chordate muscle gene regulation.

A MyoD family gene was identified in the ascidian Ciona intestinalis and designated CiMDF (Ciona intestinalis Muscle Determination Factor). Expression of CiMDF was restricted to the muscle cells of the developing embryo and the body-wall muscle of adults. Northern blots showed that two differentially regulated CiMDF transcripts were expressed during development.

Age-dependent effects of developmental lead exposure on performance in the Morris water maze.

The neurobehavioral toxicity of developmental exposure to lead (Pb) was investigated by conducting tests of spatial learning in the Morris water maze. Female Long-Evans rats were exposed to 0 or 250 ppm Pb acetate in the diet beginning 10 days prior to breeding and continued throughout gestation and lactation. Pups were weaned onto the same diets as the dams at postnatal day 20 (PN20).

Randomised trial of oral and intravenous methylprednisolone in acute relapses of multiple sclerosis.

Background: An intravenous rather than oral course of methylprednisolone is often prescribed for treating acute relapses in multiple sclerosis (MS) despite the lack of evidence to support this route of administration. Our double-blind placebo-controlled randomised trial was designed to compare the efficacy of commonly used intravenous and oral steroid regimens in promoting recovery from acute relapses in MS.

Methods: 42 patients with clinically definite relapse in MS received oral, and 38 intravenous, methylprednisolone.

The bZIP transcription factor LCR-F1 is essential for mesoderm formation in mouse development.

LCR-F1 is a mammalian bZIP transcription factor containing a basic amino acid domain highly homologous to a domain in the Drosophila Cap 'N' Collar and Caenorhabditis elegans SKN-1 proteins. LCR-F1 binds to AP1-like sequences in the human beta-globin locus control region and activates high-level expression of beta-globin genes. To assess the role of LCR-F1 in mammalian development, the mouse Lcrf1 gene was deleted in embryonic stem (ES) cells, and mice derived from these cells were mated to produce Lcrf1 null animals.

Purification and partial characterization of the OmpA family of proteins of Pasteurella haemolytica.

This study was conducted to partially characterize and identify the purity of two major outer membrane proteins (OMPs) (with molecular weights of 32,000 and 35,000 [32K and 35K, respectively]) of Pasteurella haemolytica. The 35K and 32K major OMPs, designated Pasteurella outer membrane proteins A and B (PomA and PomB, respectively), were extracted from P. haemolytica by solubilization in N-octyl polyoxyl ethylene.

Stimulation of C2C12 myoblast growth by basic fibroblast growth factor and insulin-like growth factor 1 can occur via mitogen-activated protein kinase-dependent and -independent pathways.

It is now well-recognized that the mitogen-activated protein (MAP) kinase cascade facilitates signaling from an activated tyrosine kinase receptor to the nucleus. In fact, an increasing number of extracellular effectors have been reported to activate the MAP kinase cascade, with a significant number of cellular responses attributed to this activation. We set out to explore how two extracellular effectors, basic fibroblast growth factor (bFGF) and insulin-like growth factor 1 (IGF-1), which have both been reported to activate MAP kinase, generate quite distinct cellular responses in C2C12 myoblasts.

Modulation of structure and antibacterial and hemolytic activity by ring size in cyclic gramicidin S analogs.

We have evaluated the effect of ring size of gramicidin S analogs on secondary structure, lipid binding, lipid disruption, antibacterial and hemolytic activity. Cyclic analogs with ring sizes ranging from 4 to 14 residues were designed to maintain the amphipathic character as found in gramicidin S and synthesized by solid phase peptide synthesis. The secondary structure of these peptides showed a definite periodicity in beta-sheet content, with rings containing 6, 10, and 14 residues exhibiting beta-sheet structure, and rings containing 8 or 12 residues being largely disordered.

The potential for ambulation by severely handicapped cerebral palsy patients.

Whereas walking for paraplegic patients is now a routine clinical option, ambulation for heavily handicapped cerebral palsy patients is less well established. There are good reasons for supposing that therapeutic benefits similar to that achieved with paraplegic patients are possible for this group. However, the biomechanical problems which must be overcome are different and in many ways more difficult to address.

Induction of peroxisome proliferator-activated receptor gamma during the conversion of 3T3 fibroblasts into adipocytes is mediated by C/EBPbeta, C/EBPdelta, and glucocorticoids.

The differentiation of 3T3 preadipocytes into adipocytes is accompanied by a transient induction of C/EBPbeta and C/EBPdelta expression in response to treatment of the cells with methylisobutylxanthine (MIX) and dexamethasone (DEX), respectively. In this report, we demonstrate that peroxisome proliferator-activated receptor gamma (PPARgamma) expression in 3T3-L1 preadipocytes is induced by MIX and DEX, suggesting that C/EBPbeta and C/EBPdelta may be involved in this process. Using a tetracycline-responsive expression system, we have recently shown that the conditional ectopic expression of C/EBPbeta in NIH 3T3 fibroblasts (beta2 cells) in the presence of DEX activates the synthesis of peroxisome PPARgamma mRNA.

Gramicidin S is active against both gram-positive and gram-negative bacteria.

Four linear and four cyclic analogs of gramicidin S (GS) in which D-Phe was replaced with either D-His, D-Ser, D-Tyr or D-Asn have been prepared by solid-phase peptide synthesis and characterized with respect to antibacterial, antifungal and hemolytic activity. Unlike previous reports, GS and a number of cyclic analogs were found to be active against gram-positive as well as gram-negative bacteria. GS showed MICs ranging from 3 to 12.

Antibacterial and antifungal polyine compounds from Glehnia littoralis ssp. leiocarpa.

Glehnia littoralis F. Schmidt ssp. leiocarpa (Mathias) Hult.

Structure and chromosomal location of the mouse medium-chain acyl-CoA dehydrogenase-encoding gene and its promoter.

Medium-chain acyl-coenzyme A dehydrogenase (MCAD; mouse gene Acadm; human gene ACADM) catalyzes the initial step of fatty acid beta-oxidation in mitochondria. Inherited MCAD deficiency is an autosomal recessive disorder that occurs at high frequency in humans and is associated with considerable morbidity and mortality. We have cloned and characterized mouse Acadm which spans approximately 25 kb and contains 12 exons.

HTLV-1 polymyositis.

The case is described of an HTLV-1 seropositive Jamaican woman who presented with signs and symptoms of polymyositis and myelopathy. A muscle biopsy showed features of myositis with a mononuclear inflammatory infiltrate, variation in fibre size and evidence of regeneration. Immunocytochemistry showed the mononuclear cells were composed of macrophages and T-lymphocytes suggesting a cell-mediated response.

Anchorage-dependent control of muscle-specific gene expression in C2C12 mouse myoblasts.

Our previous studies have demonstrated that expression of growth-associated genes is regulated by the adhesive state of the cell. To understand the role of cell adhesion in regulating the switch from growth to differentiation, we are studying the differentiation of mouse myoblasts into multinucleated contractile myotubes. In this report, we describe a novel means of culturing C2C12 myoblasts that permits an analysis of the role of cell adhesion in regulating the sequential induction of muscle-specific genes that control myogenesis.