Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The abilities of various extractants to recover four arsenic species [As(iii), As(v), dimethylarsinic acid (DMA), and monomethylarsonic acid (MMA)] from soils spiked with 20 micro g g(-1) As were investigated. The extractants were water, buffer solutions (citrate and ammonium dihydrogen phosphate), acidic solutions (phosphoric acid and acetic acid), a basic solution (sodium hydroxide) and household chemicals (vinegar and Coca Cola). Gentle shaking at room temperature with each extractant for 24 h gave different recoveries for the different arsenic species. With 0.1 M NaOH solution 46% As(iii), 53% DMA, 100% MMA and 84% As(v) were recovered. A rapid extraction procedure using a sonicator probe has been developed to obtain higher extraction efficiencies. Extracts of arsenic-spiked soil, SRM 2711 Montana soil and SRM 2709 San Joaquin soil were analyzed by HPLC-ICP-MS. In the SRM water extracts, DMA and MMA were identified in addition to inorganic arsenic. The solution detection limits (3s) were 0.1, 0.12, 0.13 and 0.15 ng mL(-1) for As(iii), DMA, MMA and As(v), respectively for HPLC-ICP-MS.
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PMID:Extraction of arsenic species from spiked soils and standard reference materials. 1528 14

It is well known that biofilm formation by pathogenic staphylococci on implanted medical devices leads to "chronic polymer-associated infections." Bacteria in these biofilms are more resistant to antibiotics and the immune defense system than their planktonic counterparts, which suggests that the cells in a biofilm have altered metabolic activity. To determine which genes are up-regulated in Staphylococcus aureus biofilm cells, we carried out a comparative transcriptome analysis. Biofilm growth was simulated on dialysis membranes laid on agar plates. Staphylococci were cultivated planktonically in Erlenmeyer flasks with shaking. mRNA was isolated at five time points from cells grown under both conditions and used for hybridization with DNA microarrays. The gene expression patterns of several gene groups differed under the two growth conditions. In biofilm cells, the cell envelope appeared to be a very active compartment since genes encoding binding proteins, proteins involved in the synthesis of murein and glucosaminoglycan polysaccharide intercellular adhesin, and other enzymes involved in cell envelope synthesis and function were significantly up-regulated. In addition, evidence was obtained that formate fermentation, urease activity, the response to oxidative stress, and, as a consequence thereof, acid and ammonium production are up-regulated in a biofilm. These factors might contribute to survival, persistence, and growth in a biofilm environment. Interestingly, toxins and proteases were up-regulated under planktonic growth conditions. Physiological and biochemical tests for the up-regulation of urease, formate dehydrogenase, proteases, and the synthesis of staphyloxanthin confirmed the microarray data.
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PMID:Differential gene expression profiling of Staphylococcus aureus cultivated under biofilm and planktonic conditions. 1587 Mar 58

Several cases of Parkinsonian syndrome, cognitive impairment or hyperammonemia induced by sodium valproate have been described in the literature. We report the first case presenting an association of the three adverse effects occurring with divalproate sodium prescribed for bipolar disorder: a 58-year-old man with a history of bipolar type I disorder presented with Parkinsonian syndrome and cognitive impairment of insidious onset. This patient had been treated for several years with lithium carbonate, with a successful effect on mood swings, but with distressing adverse effects such as hand tremor and diarrhoea. Lithium therapy was progressively withdrawn while sodium divalproate was initiated. Associated medications, unchanged for several years, were amisulpride (daily dose: 100 mg), liothyronine, ciprofibrate and benfluorex. The patient was treated with sodium divalproate for seven months (daily dose: 1,000 mg), and with trihexyphenidyle for one month for extrapyramidal symptoms. At hospital admission, he presented with temporal disorientation, slowed thinking, severe anterograde memory deficits, and Parkinsonian syndrome. The minimal mental state (MMS) score was 16 (maximum: 30). The patient was anxious but did no present with mood symptoms. He also developed hyperammonemia (124 micromol/liter, normal range: 15 to 60 micromol/liter) without signs or biochemical evidence of hepatic failure. Valproate concentrations were within the therapeutic ranges (79 mg/l, normal range: 50 to 100 mg/l). The CT-scan showed cerebral and cerebellar atrophy with enlarged ventricles. The electroencephalogram showed generalized slowing waves. All the symptoms resolved within one month after the withdrawal of divalproate: the extrapyramidal hypertonia resolved, the MMS score was 29. The CT-scan and the electroencephalogram returned to normal. The divalproate was replaced by lithium. After a one-year follow-up, the cognitive and neurological symptomatology did not reappear at the exception of the pre-existing hand tremor. The pathophysiology of valproate induced hyperammonemic encephalopathy remains unclear. A possible mechanism is neuronal toxicity induced by increased intracellular concentrations of glutamate and ammonium in astrocytes. Indeed, these abnormal intracellular concentrations increase the intracellular osmolarity and thus induce rise in intracranial pressure and cerebral oedema. Reversible dementia could be due to a direct toxic effect of valproate on the central nervous system or to an indirect effect mediated through valproate-induced hyperammonemia. It has been suggested that the occurrence of extrapyramidal syndrome could be explained by a disturbance in the GABAergic pathways inducing reversible dopamine inhibition. A drug adverse reaction should always be considered when a patient treated with valproate presents with extrapyramidal symptoms and cognitive disorders even when valproate concentrations are within standard therapeutic ranges.
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PMID:[A case of Parkinsonian syndrome, cognitive impairment and hyperammonemia induced by divalproate sodium prescribed for bipolar disorder]. 1597 46

Considering Alcaligenes faecalis pencillin G acylase(AfPGA), which possesses the attractive characteristics for beta-lactam antibiotics conversions, the gene of PGA was cloned into an expressing vector pKKFPGA. The recombinant plasmid contained multicopy replicon(COLE 1), trc promoter, AfPGA gene, rrnB transcript terminator and ampicillin marker transformed Escherichia coli DH5alpha. As both the recombinant plasmid and the host DH5alpha had no laclq gene, the trc promoter was always active and the AfPGA could be constitutively expressed without IPTG induction in the host DH5alpha. In the shaking flask, the recombinant cell was inoculated into the fermentation medium (tryptone 10g/L, yeast extract 5g/L, MgSO4 x 7 H2O 1g, KH2 PO4 2g/L, K2HPO4 x 3H2O 5g/L, Na2HPO4 x 12H2O 7g/L, (NH4)2SO4 1.2g/L, NH4Cl 0.2 g/L, NaCl 0.1g/L, dextrin 30g/L) and cultured at 28 degrees C for 20h. The production of AfPGA reached 2,590u/L(NIPAB method), with a cell-density-specific activity of more than 300(u/L)/A600, this yield increased 432 fold higher than the native expression of Alcaligenes faecalis . Without ammonium sulphate fractionation and dialysis, the supernatant of crude extract was directly loaded on DEAE-Sepharose CL 6B column equilibrated by phosphate buffer (50mmol/L, pH7.8), and the enzyme fraction was not absorbed on the column but impurities were absorbed. Subsequently the effluent was added ammonium sulphate to 1mol/L and loaded on Butyl-Sepharose CL 4B column equilibrated by 50mmol/L phosphate buffer pH7.8-1mol/L ammonium sulphate. The enzyme was eluted as concentration of ammonium sulphate in phosphate buffer decreased to 0, PGA was eluted. After these two column chromatography, the enzyme was enriched 20 times with a 91% activity recovery. The purified enzyme had a specific activity of 68.6u/mg protein. However, the overproduction of PGA was often limited by translocation and/or periplasmic processing steps, subsequently resulted in intracellular accumulation of various types of PGA precursors and then formed inclusion bodies in the cytoplasm and/or periplasm. In this study, 5% PGA precursors formed as inclusion bodies in the cytoplasm while no inclusion bodies formed in the periplasm. It suggested most PGA precursors were transported to the periplasm and matured to active PGA and also explained why PGA gene was highly expressed in the host DH5alpha. On the other hand, inclusion bodies in the cytoplasm indicated that the maturation of PGA in the host DHSalpha was limited by the translocation step.
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PMID:[Constitutive expression and purification of Alcaligenes faecalis penicillin G acylase in Escherichia coli]. 1597

A novel capsule system composed of sodium cellulose sulfate (NaCS), carboxymethyl cellulose (CMC) and poly[dimethyl(diallyl)ammonium chloride] (PDMDAAC) was prepared for improving the properties of NaCS/PDMDAAC capsules. The process parameters, such as CMC concentration (0, 2, 4, 6 and 8 g/L), NaCS concentration (20, 25, 30, 35 and 40 g/L), PDMDAAC concentration (20, 30, 40, 50, 60, 70 and 80 g/L), reaction time and temperature were investigated to understand their effects on the diameter, membrane thickness and mechanical strength of capsules. The optimum operation conditions for preparing NaCS-CMC/PDMDAAC capsules were determined as 6-8 g/L CMC, 35-40 g/L NaCS, 60 g/L PDMDAAC and polymerization for 30-40 min. Diffusion of substances with low molecular weight into capsules was investigated, and diffusion coefficients were calculated according to the developed model. The yeast of Candida krusei was chosen as representative cell to evaluate the effects of different cell loading on capsule mechanical strength. Meanwhile the encapsulated osmophilic C. krusei cells were cultured in 250 mL shaking flasks for 72 h to determine the cell leaking properties in short and long term.
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PMID:Preparation and characterization of NaCS-CMC/PDMDAAC capsules. 1619 44

Two compounds showing self-inhibitory action during germination of aeciospores of the comandra blister rust fungus (Cronartium comandrae Pk.) were extracted from these aeciospores by shaking with 0.2 M NH(4)HCO(3) (pH 7.8) for 4 h. One of these, the germination self inhibitor (D. A. Eppstein and F. H. Tainter, Phytopathology 66:1395-1397, 1976), was removed from the ammonium bicarbonate buffer by using chloroform. The water layer which remained contained a substance which, at ca. 10 M concentration, had no apparent effect on germ tube emergence but which inhibited normal germ tube growth. Linear germ tube growth ceased or a dendritic or vesicular pattern of growth resulted, depending on the concentration of inhibitor added to extracted germinating spores. The germ tube growth inhibitor appears to be a peptide with a molecular weight of ca. 2,000.
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PMID:Germ Tube Growth Inhibitor from Cronartium comandrae Aeciospores. 1634 35

The time course of hydrogen formation by Anabaena cylindrica was followed beneath an argon atmosphere alone and also beneath atmospheres of argon, nitrogen, and air in the presence of carbon monoxide (0.2%) and acetylene (5%). Hydrogen production beneath argon alone was comparable in rate and duration (7 to 12 days) to that which occurred beneath air in the presence of carbon monoxide (0.2%) and acetylene (5%). However, much greater longevity (16 to 26 days) and improved rates of hydrogen formation were obtained when algae were incubated beneath argon and particularly nitrogen, each supplemented with carbon monoxide and acetylene. The total hydrogen produced by these cultures was up to three times as much as that released by cultures incubated beneath argon alone. Hydrogen-oxygen ratios for argon cultures either with or without carbon monoxide and acetylene were initially 1:5 but approximated 1:2 when measured over the entire incubation period. In each case oxygen production and nitrogenase activity (acetylene reduction) continued at reduced rates after hydrogen evolution had ceased. The effects of methionine sulfoximine (2 muM), ammonium ions (0.5 mM), or both on oxygen production were generally negligible, while effects on hydrogen production were variable depending on the atmosphere used; in most cases, eventual destabilization of the system occurred. A brief comparison was made of the time courses of anaerobic and aerobic hydrogen formation by the marine cyanobacterium Calothrix membranacea. It was found that shaking of cultures was beneficial for hydrogen production but not strictly necessary. It is concluded that hydrogen production by A. cylindrica in air and particularly nitrogen in the presence of carbon monoxide and acetylene offers the best potential of the atmospheres considered on the basis of four criteria: rates and longevity of hydrogen formation, practicality of the atmosphere used, and tolerance of hydrogen evolution to slight changes in composition of the atmosphere.
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PMID:Duration of Hydrogen Formation by Anabaena cylindrica B629 in Atmospheres of Argon, Air, and Nitrogen. 1634 38

The purpose of the present study was to examine the removal of ammoniacal nitrogen (NH4-N) from synthetic wastewater using limestone (LS) and granular activated carbon (GAC) mixture as low cost adsorbent. In batch study, optimum shaking and settling times were 150 and 120 min, respectively. The LS-GAC mixture ratio of 25:15 removed about 58% NH4-N. The smaller particle size of medium yielded higher adsorption capacity. The equilibrium adsorption data followed the Freundlich isotherm (R2 > 0.98) but it showed weak bond. Adsorption kinetics were well described by the pseudo second-order rate model (R2 > 0.93). The upflow column showed that higher flow rate and initial concentration resulted in shorter column saturation time. The study showed that the usage of GAC could be reduced by combining GAC with LS for the removal of NH4-N from wastewater; thus reducing the cost of treatment.
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PMID:Physico-chemical method for ammonia removal from synthetic wastewater using limestone and GAC in batch and column studies. 1671 87

The potential of octodecyl trimethyl ammonium chloride (OTMAC)-modified attapulgite (AT) for phenol adsorption from aqueous solutions was studied. The comparison of natural AT and modified AT showed that it is possible to utilize the sonication-modified OTMAC-AT in the treatment of phenol-contaminated wastewaters. Batch sorption studies were carried out to evaluate the effect of contact time, shaking frequency, temperature and the amount of AT. The results showed that in a lab-scale reactor, at room temperature, with an amount of the modified AT added (2.5 g), and a shaking frequency of 140 rev/min, the adsorption rate of phenol could be 60.4% for a duration of 60 min. The sorption kinetics were described by a pseudo-second-order model, and the values of k and q(e) were 1.367 mg/ig min and 0.7901 ig/mg, respectively. The analysis of equilibrium data showed that the Freundlich isotherms were found to be applicable for the adsorption equilibrium data. K and 1/n were estimated to be 14.53 and 0.8438, respectively.
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PMID:Removal of phenol from aqueous solution by adsorption onto OTMAC-modified attapulgite. 1685 24

Culture medium and fermentation conditions for lipid production by Rhodosporidium toruloides were optimized with single factor and uniform design experiment. The best medium recipe was found with 70 g/L glucose, 0.1 g/L (NH4)2SO4, 0.75 g/L yeast extract, 1.5 g/L MgSO4. 7H2O, 0.4g/L KH2PO4, sterilized at 121 degrees C for 15 min, and then supplemented with ZnSO4 1.91 x 10(-6) mmol/L, CaCl2 1.50 mmol/L, MnCl2 1.22 x 10(-4) mmol/L and CuSO4 1.00 x 10(-4) mmol/L. The optimal fermentation conditions were as follows: 50 mL of medium (pH 6.0) in 250 mL Erlenmeyer flask with 10% inoculum (28h) under orbital shaking at 200 r/min for 120h at 30 degrees C. Under these conditions, yeast biomass accumulated lipids up to 76.1%.
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PMID:[Optimized culture medium and fermentation conditions for lipid production by Rhodosporidium toruloides]. 1689 4


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