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)

A detergent scrub technique using wash fluid consisting of 0.075 M phosphate-buffered saline, pH 7.9 containing 0.1 per cent Triton X-100 was evaluated for the quantitative culture of Malassezia pachydermatis from canine skin. Preliminary studies showed that the detergents Triton X-100, Tween 40 and Tween 80 were equally able to disperse suspensions of pure cultures of M pachydermatis, but that the yeast counts were significantly reduced (P < 0.001) after suspension in saline, Triton X-100 or Tween 40 for two hours. The counts in skin washings were also reduced (P < 0.001) after suspension for three hours in 0.1 and 0.05 per cent solutions of Triton X-100. Vortexing, or manual or mechanical shaking of the samples yielded comparable counts. The correlation between the counts on diseased skin measured by using detergent scrubs and a contact plate technique was highly significant (P < 0.001). The detergent scrub technique was suitable for the quantitation of M pachydermatis on canine skin provided that the samples were processed without delay.
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PMID:Evaluation of a detergent scrub technique for the quantitative culture of Malassezia pachydermatis from canine skin. 776 91

We investigated the effects of an OH. (Fe2+/H2O2) generator system on erythrocyte membrane, particularly the time-course of lipid peroxidation as estimated by measurement of conjugated dienes, thiobarbituric reactive substances (TBARS), lipofuscin-like pigments, and alpha-tocopherol. Polyunsaturated fatty acids (PUFAs), especially arachidonic acid (20:4 omega 6) and docosahexenoic acid (22:6 omega 3), were also measured. Erythrocyte membranes were suspended in phosphate buffer containing Fe2+ (200 microM) and H2O2 (1.42 mM), and incubated in a shaking water bath at 37 degrees C. Initially, there was an increase in TBARS and lipofuscin-like pigments, two well-known end products of PUFA oxidative degradation, whereas PUFAs remained unchanged (incubation time: 1 h). After two or more hours of incubation, marked lipid peroxidation was noted, with the appearance of conjugated dienes and a decrease of PUFAs, indicating that lipid peroxidation had occurred after a lag phase during which TBARS were not produced from PUFAs. This suggests that another OH. target was involved.
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PMID:Lack of correlation between TBARS production and PUFA degradation during incubation of membrane erythrocytes in an OH. (Fe2+/H2O2) generator system. 777 62

1. Two types of nylon-6 supports (small cylinders and a sponge-like derivative) were prepared for immobilizing enzymes. Nylon-6 beads were solubilized by immersion in 80% formic acid and then reprecipitated using two different types of non-solvent solutions (distilled water or a 1:1 acetone:water solution) giving rise to a sponge-like derivative and to a colloidal suspension, respectively. The latter was molded into a thin thread which was cut into small cylinders. 2. Trypsin (EC 3.4.21.4) was covalently bound to glutaraldehyde-activated nylon-6 cylinders as well as to the sponge-like derivative. The maximum (100%) apparent initial enzymatic activity was found for the trypsin bound to small cylinders, while the initial activity of trypsin bound to the sponge-like material was 61% in comparison with that of trypsin-small cylinders, under the same conditions of enzyme immobilization reaction (1 g of nylon support and 5 ml of 1.3 mg/ml trypsin in 0.1 M sodium phosphate buffer, pH 8.5, at 10 degrees C for 18 h) and of enzymatic reaction (1 g of trypsin-nylon in a batch reactor, 2 ml of 0.7% w/v azocasein solution in 50 mM borate buffer, pH 8.5, at 37 degrees C, with shaking, for 1 h). However, the decrease of activity after enzyme immobilization was more conspicuous for the trypsin-small cylinders than for the trypsin-sponge. The former retained approximately 25% of its initial activity, while the latter retained approximately 67% of its initial activity, after seven cycles of utilization for 1 h, pH 8.5, at 37 degrees C and 8 days of storage, pH 8.5, at 4 degrees C in the presence of azocasein. 3. Scanning electron microscopy was performed to visualize the surface of the support after each step of the immobilization process. The electron micrographs show that the two types of nylon supports had a rough surface, which became rougher and full of craters after treatment with 5 N HCl. On the other hand, the partially hydrolyzed nylon surface acquired the appearance of Swiss cheese after treatment with 2.5% glutaraldehyde. After reaction with the enzyme molecules the surface became rougher again.
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PMID:Nylon-6 cylinders and a sponge-like derivative as supports for immobilizing trypsin. 787 18

Efficient methods for the recovery of genetically engineered organisms (GEM) added to soil are critical if the safety of potential releases is to be evaluated and the actual release is to be monitored. Pseudomonas aureofaciens strain 3732 RN-L11 (lacZY) was added to 10 g sieved soil microcosms and incubated for 5 and 28 days. Various diluents, shaking methods, and settling of soil were examined to determine the optimum method for recovery of the GEM from the soil. Of the diluents examined, 0.1% agar gave significantly lower numbers than distilled water, 1.0% sodium metaphosphate, 1% peptone, and phosphate-buffered water. After 5 days of incubation, shaking for 10 min with glass beads and shaking for 30 min without glass beads resulted in the highest recovery of the GEM from soil, while sonification resulted in the lowest recovery. After 28 days of incubation, sonification produced significantly lower numbers than any of the other treatments. The addition of 1% CaCl2 to enhance settling significantly increased recovery efficiency. Although the use of CaCl2 in distilled water and shaking for 10 min was an effective method for recovering P. aureofaciens from a Maryland soil, when the same extraction procedure was compared with a standard technique (dd H2O, shaking for 10 min) for eight divergent soils, neither extraction method was consistently better than the other. Statistical analysis of the data showed the need for log transformation of the raw data. Four microcosm and two plate replicates for each dilution provided the greatest ability to detect differences between treatment means while maximizing experimental efficiency.
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PMID:Pseudomonas aureofaciens in soil: survival and recovery efficiency. 792 53

Aggregation is known to complicate insulin delivery and the processing and formulation of biotechnology-derived peptide/protein drugs. Shaking-induced formation of insoluble aggregates in bovine insulin and the potential role of cyclodextrins in preventing such aggregation were investigated. Insulin, dissolved in phosphate buffer, pH 7.2, and preserved with 2 mg/ml of phenol was aggregated, in triplicate, by shaking at 450 rpm for 2.5 days on a gyratory shaker. Visible aggregation was quantitated by measuring optical density in the visible range on a spectrophotometer. Solutions were then filtered through a 0.22 mu filter and the amount of insulin remaining in filtrate was determined by HPLC. Aggregation increased at lower concentrations, with solutions turning milky at 0.5 mg/ml; HPLC assay of filtrate indicated a complete loss of insulin. Under the same conditions, except for shaking, control solutions exhibited no insulin loss, excluding absorption as a cause of the insulin loss. The use of cyclodextrins (0.5 mg/ml) to stabilize insulin was investigated. alpha-, beta-, gamma- and hydroxypropyl-beta-cyclodextrin, each at 1.5% level, were used to prevent aggregation. The efficacy of cyclodextrins in preventing aggregation (% insulin aggregated in parentheses), was: hydroxypropyl-beta- (15) approximately beta- (18) > alpha- (54). No protection was observed with gamma-cyclodextrin.
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PMID:Minimization of shaking-induced formation of insoluble aggregates of insulin by cyclodextrins. 806 77

The bacterium Salmonella typhimurium TA98 (TA98) is commonly used in the Ames test to detect frameshift mutations. Published Ames test results for fluoride mutagenicity are inconsistent. We considered that this might be due to an unnoticed variable in experimental conditions. Al and F, both present in finished drinking water, form a stable complex. The effect of Al and F uptake by TA98 cells was evaluated and any effect of Al on Ames test results for F was also determined. A known number of TA98 cells in 0.1 M potassium phosphate buffer (PPB, pH 7.4) was incubated with buffer only, and various concentrations of Al as AlCl3, F as NaF, or aluminum and fluoride (Al: F, 1: 62.5 w/w) for 1 h at 37 degrees C in a shaking incubator. Neither F (19 and 190 ppm), Al (0.3 and 3 ppm), nor Al:F (7.6 ppb-3 ppm: 0.45-190 ppm) was found to be mutagenic as assessed by a modification of the Ames standard plate incorporation assay. Intracellular Al accumulated in a concentration-dependent manner from 0.5 to 4.5 ppm, then decreased as Al was increased to 9.5 ppm. Intracellular F was below the limit of detection (0.2 ppm) even when the medium contained 589 ppm F. However, F was taken up from media containing greater than 200 ppm F, providing that aluminum was also present. Experiments carried out using N-2-hydroxyethyl-piperazine-N'-2-ethanesulfonic acid (HEPES) buffer (100 mM, pH 7.4) gave similar results for F uptake, suggesting the Al requirement for F uptake is not an artifact caused by buffer chelation. However, Al uptake was not biphasic from HEPES buffer, but increased with dose over the range studied (1.5-9.0 ppm). While F did not appear to cause mutations in the presence or absence of Al, it was concluded that the mutagenicity test, using TA98, is not suitable for the evaluation of F mutagenicity.
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PMID:Effect of aluminum on fluoride uptake by Salmonella typhimurium TA98; implications for the Ames mutagenicity assay. 812 55

Quantitative exposure assessments made using biologically relevant markers will facilitate epidemiological studies of risk from environmental carcinogens. Blood proteins are readily accessible macromolecules that have been shown to be targets for activated chemical carcinogens. Serum albumin is quantitatively the most abundant target for aflatoxin B1 and the measurement of aflatoxin-serum albumin adducts has been used to detect exposed individuals. The goal of these experiments was to devise an analytical procedure that would increase the overall recovery of aflatoxin adducts in serum albumin, and thereby improve the accuracy of exposure monitoring. The method developed consisted of the following procedures. Proteins were precipitated from serum (< or = 100 microliters) with 80% ammonium sulfate, with incubation at 4 degrees C for 2 h. Following dialysis against phosphate-buffered saline (pH 7.0 for 3 h at 4 degrees C), the proteins were digested with protease (Pronase) (1:4.1 w/w enzyme:protein) for 15 h at 37 degrees C with shaking. Enzyme and other undigested proteins were precipitated with acetone (1:2 v/v, 40 min, 4 degrees C). After evaporation of the acetone under vacuum, levels of aflatoxin B1-albumin adducts were determined by radioimmunoassay carried out on 300 microliters fractions. This procedure obviated the isolation of albumin prior to analysis and reduced interference in the radioimmunoassay. High recoveries of aflatoxin B1 adducts were achieved together with a low limit of detection. The applicability of the procedure in epidemiological studies of human aflatoxin exposure was illustrated by results of analysis of aflatoxin-albumin adducts in serum samples from residents of Chongming Island, People's Republic of China.
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PMID:Quantitative analysis of aflatoxin-albumin adducts. 850 8

The shaking pup, a canine mutant, carries a point mutation in the myelin proteolipid protein (PLP) gene that causes dysmyelination of the central nervous system (CNS) with resultant tremor, seizures, and other persistent neurological deficits. The developmental potential of glial cells in the shaking pup CNS and peripheral nervous system (PNS) was evaluated by quantitative analysis of the expression of several glial-specific genes. All of the myelin-associated genes demonstrated developmental patterns of expression similar to those observed in the controls, but at significantly reduced levels. Expression of the genes for the major CNS myelin proteins, PLP and the myelin basic protein, are most dramatically affected in the shaking pup, although reduced expression levels are observed for other oligodendrocyte-specific genes such as 2',3'-cyclic nucleotide 3'phosphodiesterase and glucose phosphate dehydrogenase. The pattern of gene expression in the shaking pup indicates that the oligodendrocytes experience an inhibition in development after the myelination program has begun. There appears to be little evidence for an astrocytic response to the dysmyelinating condition at the RNA level, but we present evidence for ectopic expression of P0 mRNA in the CNS. Expression of the P0 and PLP genes in the sciatic nerve appears to be normal, reinforcing previous reports that PNS myelination is unaffected by the mutation in the PLP gene.
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PMID:Molecular analysis of glial cell development in the canine 'shaking pup' mutant. 889 46

We generated Dictyostelium double mutants lacking the two F-actin crosslinking proteins alpha-actinin and gelation factor by inactivating the corresponding genes via homologous recombination. Here we investigated the consequences of these deficiencies both at the single cell level and at the multicellular stage. We found that loss of both proteins severely affected growth of the mutant cells in shaking suspension, and led to a reduction of cell size from 12 microns in wild-type cells to 9 microns in mutant cells. Moreover the cells did not exhibit the typical polarized morphology of aggregating Dictyostelium cells but had a more rounded cell shape, and also exhibited an increased sensitivity towards osmotic shock and a reduced rate of phagocytosis. Development was heavily impaired and never resulted in the formation of fruiting bodies. Expression of developmentally regulated genes and the final developmental stages that were reached varied, however, with the substrata on which the cells were deposited. On phosphate buffered agar plates the cells were able to form tight aggregates and mounds and to express prespore and prestalk cell specific genes. Under these conditions the cells could perform chemotactic signalling and cell behavior was normal at the onset of multicellular development as revealed by time-lapse video microscopy. Double mutant cells were motile but speed was reduced by approximately 30% as compared to wild type. These changes were reversed by expressing the gelation factor in the mutant cells. We conclude that the actin assemblies that are formed and/or stabilized by both F-actin crosslinking proteins have a protective function during osmotic stress and are essential for proper cell shape and motility.
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PMID:The role of the cortical cytoskeleton: F-actin crosslinking proteins protect against osmotic stress, ensure cell size, cell shape and motility, and contribute to phagocytosis and development. 893 86

The excitatory effect of bradykinin (BK) and of low pH on nociceptors appears to partly depend on secondary release of prostaglandins from the surrounding tissue. Rat skin, in vitro, is introduced as a novel model to measure basal and stimulated release of PGE2 and, in future, other substances relevant to nociception, such as neuropeptides. Flaps of hairy skin (n=57) from the rat saphenous region of the hindpaw were subcutaneously excised and fixed on acrylic rods, the corium side exposed. The preparations were equilibrated in carbogen gassed "synthetic interstitial fluid" (SIF) for 30 minutes. The skin flaps were then immersed for 5 minutes each in 9 consecutive glass tubes, which were mounted in a shaking bath at 32 degrees C. Each tube was filled with 5 ml of gassed SIF, the third tube contained inflammatory mediator(s) dissolved in SIF or solutions of low pH. After passage of the skin flap, the eluates were deep frozen (-70 degrees C) and the PGE2 content measured, off-line, using an enzyme immuno-assay. As stimulants, BK at 10(-5) M (n=9) and 10(-6) M (n=4) and BK in equimolar combination with histamine (HA) and serotonin (5-HT; 10(-5) M: n=8, 10(-6) M: n=6, 10(-7) M: n=6) dose-dependently increased PGE2 release. Considering the total amount of PGE2 secreted the combination of inflammatory mediators caused a significantly greater release of PGE2 at 10(-5) and 10(-6) M (p<0.01, Kruskal-Wallis test) than BK stimulation alone. Racemic flurbiprofen caused a profound depression of basal and stimulated release. Solutions of high proton concentration are known to stimulate and sensitize nociceptors. However, phosphate buffered SIF at pH 6.1 and 6.4 caused a substantial and significant decrease of the PGE2 release, probably due to low-pH block of phospholipases. Thus, algogenic potency of mediators does not necessarily match their pro-inflammatory action.
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PMID:Stimulated prostaglandin E2 release from rat skin, in vitro. 962 3


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