Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0009443 (cold)
 92,137 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A monoclonal antibody, Leo Mel 3, raised against a melanoma cell line (LiBr), binds to a carbohydrate determinant of cell surface gangliosides, the simplest of which is GD3. This monoclonal antibody was screened for by its capacity to block the recognition and lysis of the melanoma cells by cytotoxic T-lymphocytes with anomalous killer cell function, illustrating a novel approach for identifying monoclonal antibody to biologically relevant tumor-associated antigens. Leo Mel 3 reacted selectively with melanoma cells by indirect immunofluorescent and immunoperoxidase staining; it reacted with tissue from all primary and metastatic melanoma tested, and it bound to cells from all but one of six cultured melanoma cell lines. Leo Mel 3 did not react with a variety of carcinomas, lymphomas, leukemias, and other neuroectodermal tumors, nor with adult or fetal tissues, except fetal liver. Very weak staining of cutaneous basal melanocytes was noted in a minority of skin sections, and 50 to 80% of melanocytes in four of seven benign nevi showed weak to moderate reactivity. The antibody was relatively specific for human adherent melanoma cells, since it did not bind to the adherent murine B16 melanoma line nor to a nonadherent human melanoma cell line (PMC-22). Expression of the Leo Mel 3-defined antigen was unrelated to changes in cell cycle. When cells from an adherent melanoma cell line were detached and maintained briefly in suspension culture, the cells became markedly less reactive with Leo Mel 3 and, after readherence to plastic, they rapidly reexpressed higher levels of the ganglioside antigen; since Leo Mel 3 prevented attachment and growth of melanoma cells in vitro, a functional role for the ganglioside is suggested in cell adhesion and metastasis. Differentiation of melanoma cells with dimethyl sulfoxide, retinoic acid, and theophylline resulted in a marked and selective increase in the amount of Leo Mel 3-defined antigen, together with an increase in the target cell binding ability of these cells, assessed by cold target competition assays using anomalous killer cells.
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PMID:Fluctuations in the expression of a glycolipid antigen associated with differentiation of melanoma cells monitored by a monoclonal antibody, Leo Mel 3. 379 Dec 9

A Swedish family with Paramyotonia congenita (Eulenburg) (PMC) is presented. Clinical neurological examination, neurophysiological examination (n = 5) and muscle biopsy (n = 4) were performed. Different clinical features were found in various combinations in the individual family members. The clinical symptoms were: (1) cold-induced myotonia, (2) attacks of weakness, (3) persistent weakness and (4) no symptoms but other signs of muscle affection. In the patients with myotonia, the neurophysiological examination showed spontaneous myotonic discharges which were frequent at room temperature but disappeared after cooling. Furthermore, the amplitude of M. abductor digiti minimi compound action potential, during supramaximal ulnar nerve stimulation, decreased significantly after cooling. In the patients with persistent weakness there were no spontaneous myotonic discharges, but myopathic abnormalities were found in proximal muscle. In the patients with myotonia as well as in the patients with manifest muscle weakness, muscle biopsy showed a variation of muscle fibre diameters, centrally located nuclei, occasional atrophic fibers and an atrophy of type IIB muscle fibres. These findings are unspecific but have been described in PMC patients in earlier studies. An ancestor to the family, who had myotonia, lived in the same town and at the same time as Albert Eulenburg, which may suggest that this family is a part of the originally described family (1).
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PMID:Paramyotonia congenita (Eulenburg): clinical, neurophysiological and muscle biopsy observations in a Swedish family. 842 9

Genetic analysis of the adult muscle sodium channel alpha-subunit, SCN4A gene on chromosome 17q, was performed by means of PCR technique in a Swedish family with paramyotonia congenita (Eulenburg) (PMC). The mutation was found in four family members and consisted of a C to T transition affecting the fourth domain of the sodium channel protein. This mutation has earlier been described in other families with paramyotonia congenita. All family members carrying the mutation had cold-induced paradoxical myotonia, myotonic bursts on EMG, and a type IIB atrophy on muscle biopsy. Three of them had slight CK elevation and two had episodes of paralysis. On the basis of clinical findings in this family, persistent proximal muscle weakness, myopathic EMG abnormalities, a type IIB atrophy on muscle biopsy and no symptoms but other signs of muscle affection, were earlier suggested as clinical features of PMC. However, genetic analysis revealed that family members with these symptoms and findings did not have the mutation, indicating that these features are not due to PMC.
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PMID:C4342T-mutation in the SCN4A gene on chromosome 17q in a Swedish family with paramyotonia congenita (Eulenburg)--correlations with clinical, neurophysiological and muscle biopsy data. 919 4

The authors report a Japanese family with dominantly inherited heat-induced myotonia and cold-induced paralysis with hypokalemia. This phenotype is associated with a novel mutation in the voltage-dependent skeletal muscle sodium channel alpha subunit (SCN4A). This Pro1158Ser mutation is localized between the fourth and fifth transmembrane segments of domain III in SCN4A and may give rise to a new function; that is, thermosensitive permeability changes of the sodium channel.
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PMID:Temperature-sensitive sodium channelopathy with heat-induced myotonia and cold-induced paralysis. 1085 91

The total mercury content in urine was determined by inductively coupled plasma mass spectrometry with the so-called cold vapour method after on-line oxidative treatment of the sample in a microwave oven (FI-MW-CV-ICPMS). Use of a KBr/KBrO(3) mixture, microwave digestion, and the final oxidation with KMnO(4), assure the complete recovery of the organic forms of Hg which would be difficult to determine otherwise if using only the CV-ICPMS apparatus. Quantitative recoveries were obtained for phenyl Hg chloride (PMC), dimethyl Hg (DMM), Hg acetate (MA) and methyl Hg chloride (MMC). Use of automatic flow injection microwave systems (FI-MW) for sample treatment reduces environmental contamination and allows detection limits suitable for the determination of reference values. Since no certified reference materials were commercially available in the concentration ranges of interest, the accuracy of the proposed procedure has been assessed by analysing a series of urine samples with two independent techniques, ICP-MS and AAS. When using the FI-MW-CV-ICP-MS technique, the detection limit was assessed at 0.03microg/L Hg, while with FI-MW-CV-AAS it was 0.2microg/L Hg. The precision of the method was less than 2-3% for FI-MW-CV-ICP-MS and about 3-5% for FI-MV-CV-AAS at concentrations below 1microg/L Hg. These results show that ICP-MS can be considered as a "reference technique" for the determination of total urinary Hg at very low concentrations, such as are present in non-exposed subjects.
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PMID:Determination of total urinary mercury by on-line sample microwave digestion followed by flow injection cold vapour inductively coupled plasma mass spectrometry or atomic absorption spectrometry. 1212 19

The gene encoding catalase from the psychrophilic marine bacterium Vibrio salmonicida LFI1238 was identified, cloned and expressed in the catalase-deficient Escherichia coli UM2. Recombinant catalase from V. salmonicida (VSC) was purified to apparent homogeneity as a tetramer with a molecular mass of 235 kDa. VSC contained 67% heme b and 25% protoporphyrin IX. VSC was able to bind NADPH, react with cyanide and form compounds I and II as other monofunctional small subunit heme catalases. Amino acid sequence alignment of VSC and catalase from the mesophilic Proteus mirabilis (PMC) revealed 71% identity. As for cold adapted enzymes in general, VSC possessed a lower temperature optimum and higher catalytic efficiency (k (cat)/K (m)) compared to PMC. VSC have higher affinity for hydrogen peroxide (apparent K (m)) at all temperatures. For VSC the turnover rate (k (cat)) is slightly lower while the catalytic efficiency is slightly higher compared to PMC over the temperature range measured, except at 4 degrees C. Moreover, the catalytic efficiency of VSC and PMC is almost temperature independent, except at 4 degrees C where PMC has a twofold lower efficiency compared to VSC. This may indicate that VSC has evolved to maintain a high efficiency at low temperatures.
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PMID:Cold adapted features of Vibrio salmonicida catalase: characterisation and comparison to the mesophilic counterpart from Proteus mirabilis. 1660 13

The cold-adapted catalase from the fish-pathogenic bacterium Vibrio salmonicida (VSC) has recently been characterized and shown to be two times more catalytically efficient compared with catalase from the mesophilic human pathogen Proteus mirabilis [PMC; Lorentzen et al. (2006), Extremophiles, 10, 427-440]. VSC is also less temperature-stable, with a half-life of 5 min at 333 K compared with 50 min for PMC. This was the background for solving the crystal structure of the cold-adapted VSC to 1.96 A and performing an extensive structural comparison of VSC and PMC. The comparison revealed that the entrance (the major channel) leading to the catalytically essential haem group, is locally more flexible and slightly wider in VSC. This might explain the enhanced catalytic efficiency of the nearly diffusion-controlled degradation of hydrogen peroxide into water and molecular oxygen in VSC. The reduced thermal stability of the cold-adapted VSC may be explained by a reduced number of ion-pair networks. The four C-terminal alpha-helices are displaced in the structures, probably owing to missing ionic interactions in VSC compared with PMC, and this is postulated as an initiation site for unfolding the cold-adapted enzyme. VSC is the first crystal structure reported of a cold-adapted monofunctional haem-containing catalase.
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PMID:The first structure of a cold-active catalase from Vibrio salmonicida at 1.96 A reveals structural aspects of cold adaptation. 1724 7

Familial hyperkalemic periodic paralysis (PP) is a dominantly inherited muscle disease characterized by attacks of flaccid weakness and intermittent myotonia. Some patients experience muscle stiffness that is aggravated by cold and exercise, bordering on the diagnosis of paramyotonia congenita. Hyperkalemic PP and paramyotonia congenita are allelic diseases caused by gain-of-function mutations of the skeletal muscle sodium channel, Nav1.4, which is essential for the generation of skeletal muscle action potentials. In this review, the functional and clinical consequences of the mutations and therapeutic strategies are reported and the differential diagnoses discussed. Also, the question is addressed of whether hyperkalemic PP is truly a different entity than normokalemic PP. Additionally, the differential diagnosis of Andersen-Tawil syndrome in which hyperkalemic PP attacks may occur will be briefly introduced. Last, because hyperkalemic PP has been described to be associated with an R83H mutation of a MiRP2 potassium channel subunit, evidence refuting disease-causality in this case will be discussed.
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PMID:Genotype-phenotype correlation and therapeutic rationale in hyperkalemic periodic paralysis. 1739 31

The Q270K mutation of the skeletal muscle Na(+) channel alpha subunit (Nav1.4) causes atypical paramyotonia with a striking sensitivity to cold. Attacks of paralysis and a drop in the compound muscle action potential (CMAP) are exclusively observed at cold. To understand the pathogenic process, we studied the consequences of this mutation on channel gating at different temperatures. WT or Q270K recombinant Nav1.4 channels fused at their C-terminal end to the enhanced green fluorescent protein (EGFP) were expressed in HEK-293 cells. Whole-cell Na(+) currents were recorded using the patch clamp technique to examine channel gating at 30 degrees C and after cooling the bathing solution to 20 degrees C. Mutant channel fast inactivation was impaired at both temperatures. Cooling slowed the kinetics and enhanced steady-state fast inactivation of both mutant and WT channels. Mutant channel slow inactivation was fairly comparable to that of the WT at 30 degrees C, but became clearly abnormal at 20 degrees C. Cooling enhanced slow inactivation in the WT by shifting the voltage dependence toward hyperpolarization, but induced the opposite effect in the mutant. Destabilization of mutant channel slow inactivation in combination with defective fast inactivation is expected to increase the susceptibility to prolonged membrane depolarization, and can ultimately lead to membrane inexcitability and paralysis at cold. Thus, abnormal temperature sensitivity of slow inactivation can be a determinant pathogenic factor, and should therefore be more widely considered in thermosensitive Na(+) channelopathies.
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PMID:Cold-induced disruption of Na+ channel slow inactivation underlies paralysis in highly thermosensitive paramyotonia. 1922 Nov 25

We report on a Japanese 13-year-old male without a family history of muscle disease admitted to our hospital due to an elevated serum creatine kinase. From the age of 3 he was complaining of muscle stiffness during and after exercise. At the age of 7 he experienced muscle stiffness and weakness during long-distance running, which would continue till the next day, disappearing only after resting for a day. Upon examination, we noted that repeated eyelid contractions induced myotonia that increased in the cold. Electromyography revealed myotonic discharge in the tongue muscle. Genetic analysis revealed a mutation of Nav1.4, M1592V. Although this mutation had originally been reported in families with Hyperkalemic periodic paralysis (Hyper PP), we diagnosed as paramyotonia congenita due to the symptoms of exercise and cold-induced myotonia without an attack of generalized weakness. This case suggest that sodium channelopathy is very rare, but should be considered in the differential diagnosis of an elevation of serum creatine kinase even if coexisting myotonia is only mild.
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PMID:[A case of muscle sodium channelopathy with markedly high value of serum creatine kinase and mild eyelid myotonia]. 2140 12


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