Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1762617 (weakness)
 37,932 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied a 33-year-old woman with a negative family history. Both of her parents were examined clinically by nerve conduction velocities (NCVs) and EMG, with normal results. The clinical onset of her condition was at 24 months, with severe weakness and atrophy of her feet and hands, but the proximal muscles were relatively spared. She had bilateral pes cavus, distal weakness and hypesthesia for touch and proprioception, areflexia, claw hands, and severe thoracolumbar kyphoscoliosis. NCVs showed absent motor and sensory responses and EMG revealed diffuse fibrillation potentials. Molecular genetic studies indicated a de novo dominant missense point mutation of exon 3 of the peripheral myelin protein 22 gene at nucleotide 264 that caused the replacement of serine with leucine.
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PMID:Dejerine-Sottas disease with de novo dominant point mutation of the PMP22 gene. 767 44

A base-pair resolution method for determining nucleosome position in vitro has been developed to com- plement existing, less accurate methods. Cysteaminyl EDTA was tethered to a recombinant histone octamer via a mutant histone H4 with serine 47 replaced by cysteine. When assembled into nucleosome core particles, the DNA could be cut site specifically by hydroxyl radical-catalyzed chain scission by using the Fenton reaction. Strand cleavage occurs mainly at a single nucleotide close to the dyad axis of the core particle, and assignment of this location via the symmetry of the nucleosome allows base-pair resolution mapping of the histone octamer position on the DNA. The positions of the histone octamer and H3H4 tetramer were mapped on a 146-bp Lytechinus variegatus 5S rRNA sequence and a twofold-symmetric derivative. The weakness of translational determinants of nucleosome positioning relative to the overall affinity of the histone proteins for this DNA is clearly demonstrated. The predominant location of both histone octamer and H3H4 tetramer assembled on the 5S rDNA is off center. Shifting the nucleosome core particle position along DNA within a conserved rotational phase could be induced under physiologically relevant conditions. Since nucleosome shifting has important consequences for chromatin structure and gene regulation, an approach to the thermodynamic characterization of this movement is proposed. This mapping method is potentially adaptable for determining nucleosome position in chromatin in vivo.
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PMID:Mapping nucleosome position at single base-pair resolution by using site-directed hydroxyl radicals. 864 38

A 28-year-old man had complaints of muscle weakness in both his legs and fingers. Moderate degrees of symmetrical atrophy adn weakness of the bilateral lower limbs, moderate degree of muscle atrophy was also noticed distal to the lower one third of the upper thigh. A moderate degree of weakness of the anterior tibial, extensor digitorum and peroneus muscles was also noted. Pes cavus deformity was evident bilaterally. Knee jerk was normal, and Achilles tendon reflex was absent without pathologic reflexes. He could not walk on his heels. Vibratory sensation was severely decreased in the toes, and both touch and pain sensations were slightly decreased on the dorsum of the feet. The median motor nerve conduction velocity was 28.9 m/sec with a prolonged distal latency. An amplitude of M-wave evoked by electrical stimulation of the median nerve 1 mV. No M-wave was obtained from stimulation of the tibial nerve, and no sensory nerve action potentials were elicited from electrical stimulation of the median and sural nerves. Histologic studies of the biopsied sural nerve revealed the occasional presence of internodes with a thin myelin sheath and a decrease in the density of large myelinated fibers. Small and atypical onion-bulbs were occasionally observed by electron microscopy. Based on the neurological examination and nerve conduction study of the family members, a sister, mother and grandmother of the proband were found to be mildly affected without any disability in their daily activities. However, the father and an uncle on the mother's side of the proband were normal. Therefore, we concluded clinically that this family had HMSN type I with autosomal dominant inheritance or X-linked HMSN. In the studies of fluorescence in situ hybridization and restriction fragment length polymorphism of the genomic DNA of the proband, a DNA duplication in chromosome 17p11.2-12 was not observed. A single-strand conformational polymorphism analysis of the genomic DNA encoding connexin32 (Cx32) revealed the abnormal band different from that of the control. A sequence analysis of the genomic DNA obtained by use of the polymerase chain reaction was also performed. It revealed that there was a mutant allele, a cytosine to thymine substitution of the nucleotide position 140, which caused a substitution of leucine for serine at amino acid position 26. The proband's mother was heterozygous for the mutant allele and the normal allele. This type of Cx32 mutation was different from any type of Cx32 mutation reported in the literature. The mutation in this family is located in the first transmembrane portion of Cx32, and may alter the function of Cx32 protein, as well as lead to the functional and structural abnormalities of the myelin sheath at the nodes of Ranvier and Schmidt-Lanterman's incisures, where Cx32 is present. This is the first Japanese X-linked HMSN family showing a new type of mutation of Cx32 gene with clinical findings and a histologic evaluation of the sural nerve.
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PMID:[A family of X-linked motor and sensory neuropathy with a new type of connexin32 mutation]. 866 24

A 32 year old woman with Dejerine-Sottas disease and negative family history is reported. Clinical onset of her condition was with congenital weakness of her distal four extremities, accompanied by peripheral facial nerve weakness, deafness, and nystagmus. She has used a wheelchair all her life. Sural nerve biopsy showed proliferation of Schwann cells, extensive endoneural fibrosis, axon loss, and demyelination. MNCVs showed marked slowing. MRI of the brain was normal. Molecular genetic studies indicated a de novo dominant missense point mutation of exon 3 of the peripheral myelin protein 22 gene at nucleotide 264 causing replacement of serine with leucine.
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PMID:Dejerine-Sottas disease with sensorineural hearing loss, nystagmus, and peripheral facial nerve weakness: de novo dominant point mutation of the PMP22 gene. 900 43

Emery-Dreifuss muscular dystrophy (EDMD) is an inherited muscular disorder characterized by the triad of progressive weakness in humero-peroneal muscles, early onset contractures and cardiomyopathy with conduction block that shows a high risk of sudden death. In 1994, the gene responsible for X-linked EDMD has been identified to Xq28 (designated as STA), that encodes a serine-rich protein of 254 amino acids, named emerin. In 1996, we discovered a nuclear membrane localization of emerin in the normal skeletal, cardiac and smooth muscles, but not in the tissues from patients with X-linked EDMD who had a nonsense mutation in the gene. In conclusion, molecular and genetic analyses of emerin are essential for accurate diagnosis of patients with EDMD.
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PMID:[Emery-Dreifuss muscular dystrophy]. 943 33

The voltage-gated sodium channel SCN8A is associated with inherited neurological disorders in the mouse that include ataxia, dystonia, severe muscle weakness, and paralysis. We report the complete coding sequence and exon organization of the human SCN8A gene. The predicted 1980 amino acid residues are distributed among 28 exons, including two pairs of alternatively spliced exons. The SCN8A protein is evolutionarily conserved, with 98.5% amino acid sequence identity between human and mouse. Consensus sites for phosphorylation of serine/threonine and tyrosine residues are present in cyoplasmic loop domains. The polymorphic (CA)n microsatellite marker D12S2211, with PIC = 0.68, was isolated from intron 10C of SCN8A. Single nucleotide polymorphisms in intron 19 and exon 22 were also identified. We localized SCN8A to chromosome band 12q13.1 by physical mapping on a YAC contig. The cDNA clone CSC-1 was reported by others to be a cardiac-specific sodium channel, but sequence comparison demonstrates that it is derived from exon 24 of human SCN8A. The genetic information described here will be useful in evaluating SCN8A as a candidate gene for human neurological disease.
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PMID:Exon organization, coding sequence, physical mapping, and polymorphic intragenic markers for the human neuronal sodium channel gene SCN8A. 982 31

Emery-Dreifuss muscular dystrophy (EDMD) is an X-linked recessive muscular dystrophy characterized by early contractures of the elbows, Achilles tendons and spine, slowly progressive muscle wasting and weakness, and cardiomyopathy associated with cardiac conduction defects. The emerin gene has been mapped to Xq28 and encodes a 34-kDa serine-rich protein, emerin, which has been localized to the nuclear envelope in a wide variety of tissues, including skeletal and cardiac muscle. Mutations spanning the emerin gene have been identified in patients with EDMD. We present here the effect, on emerin protein expression, of two missense mutations identified in unrelated EDMD patients. These alterations predict the replacement of a proline residue at position 183 with either a histidine or a threonine. Biochemical analysis has demonstrated that the mobility and expression levels of the mutant forms of emerin are indistinguishable from that of wild-type emerin, but that they have weakened interactions with nuclear lamina components. In comparison with the usual EDMD phenotype, patients with P183 missense mutations have a later age at onset of first symptoms, elbow contractures, ankle contractures, upper limb weakness and lower limb weakness, but there is no difference for the age at onset of cardiac involvement. This is the first report of protein studies on patients with missense mutations resulting in the clinical features of EDMD. These studies demonstrate the importance of proline 183 for the proper structure/function of emerin.
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PMID:Changes at P183 of emerin weaken its protein-protein interactions resulting in X-linked Emery-Dreifuss muscular dystrophy. 1032 52

Emery-Dreifuss muscular dystrophy (EDMD) is an X-linked recessive or autosomal dominant progressive muscular dystrophy characterized by progressive muscle wasting and weakness with scapulo-humero-peroneal distribution, early contracture and cardiomyopathy with conduction block. The responsible gene for EDMD, designated as 'STA', has been mapped to Xq 28 and cloned. It encodes a serine-rich protein of 254-amino-acid, called 'emerin', localized in the inner nuclear rim. We performed genetic analysis of a 23-year-old male clinically diagnosed as EDMD and found a novel point mutation. Total RNA was extracted from skeletal muscle and reverse-transcription and polymerase chain reaction amplification was performed using a set of oligonucleotide primers between 5'-flanking site of exon 1 and exon 4. Our patient gave a smaller PCR product (about 30 bp) than normal control. The determined cDNA sequence revealed a deletion of 29 bp, spanning position 164 to 192 in exon 1. To clarify the mutant allele, we performed genomic DNA sequence. Genomic DNA sequence from the initiation of exon 1 to the upstream lesion of exon 2 confirmed a novel point mutation G to C, at nucleotide 197 in the donor splice site of intron 1. This point mutation may interfere with the correct splicing of the mRNA and cause frameshift, resulted in truncation of predicted protein by premature stop. We report a novel point mutation G to C, at nucleotide 197 in the intron 1 of STA gene corresponding the truncation of predicted protein, which differs from any of the previously reported mutations.
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PMID:[A novel splice-site mutation in the STA gene in a Japanese patient with Emery-Dreifuss muscular dystrophy]. 1068 37

Plasma levels of amino acids were measured by ion-exchange, high-pressure liquid chromatography in 30 ambulatory patients with chronic obstructive pulmonary disease (COPD; mean +/- SD: age 64 +/- 13 y and forced expiratory volume in 1 s [FEV1] 0.85 +/- 0.25 L) and 30 age- and sex-matched healthy control subjects with regard to nutritional status, resting energy expenditure (REE), and pulmonary function. The ratio of branched-chain amino acids to aromatic amino acids was significantly (P < 0.001) decreased in COPD patients and was significantly correlated with percentage of ideal body weight (r = 0.403, P < 0.05), percentage of arm-muscle circumference (r = 0.492, P < 0.01), and %FEV1 (r = 0.467, P < 0.05). Plasma levels of alanine and cysteine were decreased, whereas levels of glutamine, aspartic acid, serine, and ornithine were elevated in COPD patients as opposed to control subjects. The ratio of resting energy expenditure to predicted resting energy expenditure was negatively correlated with the ratio of branched-chain to aromatic amino acids (r = -0.716, P < 0.01), percentage of arm-muscle circumference (r = -0.770, P < 0.05), %FEV1 (r = -0.839, P < 0.01), and the maximal inspiratory pressure (r = -0.803, P < 0.001). Underweight COPD patients also exhibited a greater degree of hyperinflation (percentage of residual volume = 205 +/- 15 for underweight patients and 156 +/- 8 for normal-weight patients). In conclusion, a decrease in plasma levels of branched-chain amino acids in relation to hypermetabolism, possibly resulting from the severity of COPD and respiratory muscle weakness, and various disturbances in plasma amino-acid levels were found in underweight COPD patients.
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PMID:Plasma levels of amino acids and hypermetabolism in patients with chronic obstructive pulmonary disease. 1124 Mar 35

Organophosphorus compounds are inhibitors of serine hydrolases. Some of these compounds produce, in addition to their high acute toxicity, a more persistent effect: organophosphate-induced delayed neuropathy (OPIDN). The putative molecular entity whose inhibition is thought to be responsible for OPIDN is the neuropathy target esterase (NTE). Although in vitro NTE is resistant to paraoxon (PX), occasional case reports have associated PX with OPIDN. To assess clinically whether or not high-dose i.v. PX causes OPIDN in mini pigs, 14 mini pigs were anaesthesized, intubated and mechanically ventilated. In a first set of experiments eight pigs received 1 mg PX kg(-1) body weight (BW) dissolved in alcohol. Two control animals received alcohol in a corresponding amount. After infusion of PX, survival of the animals during the acute phase of intoxication was achieved by intensive-care support, using appropriate drugs and fluids according to a pre-established protocol. The mini pigs were extubated 1036 +/- 363 min later (mean +/- SD). The pigs were observed prior to PX application and for 6 weeks thereafter for any abnormalities and/or signs of OPIDN, such as leg weakness, ataxia and paralysis. Observations were graded on a scale for three categories (position, motor deficiency, reaction), with a maximal cumulative score of 9. In a second set of experiments (four additional pigs) larger PX doses were used (3, 9, 27 and 81 mg kg(-1) BW). After recovering from general anaesthesia/surgery, within 2 weeks all animals reached the initial score on the scale. It can be concluded that high-dose i.v. PX exposure does not induce OPIDN in mini pigs during the 6-week observation period.
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PMID:High-dose intravenous paraoxon exposure does not cause organophosphate-induced delayed neuropathy (OPIDN) in mini pigs. 1148 57


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