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

Human blood cells were washed and treated by PEG 6 000 (40% solution in BME) at 37 degrees for 15 min. A strong agglutination was observed. After dilution with 3 vol. of BME and shaking, microscopic examination at low magnification revealed small aggregates disseminated in dispersed population of erythrocytes. These aggregates were shown to be formed by a polymorphonuclear cell closely surrounded by erythrocytes. The possible explanation of the formation of such "Rosettes" was briefly discussed.
 ...
PMID:[Formation of "Rosettes" induced by polyethylene glycol]. 77 62

The importance of the components of a tissue culture media, Leibovitz-15 (L-15), for maintaining viability of hypothermically preserved hepatocytes was analyzed. Hepatocytes isolated from rat livers were incubated at 5 degrees C in an oxygenated environment with continuous shaking (to simulate organ perfusion preservation). L-15 + 5 g% polyethylene glycol (PEG) or variants of this solution were used as the preservation media. After 48 hr of storage, hepatocyte viability was assessed by measuring the release of LDH into the incubation medium and cell volumes were determined. Following 90 min of normothermic incubation (to simulate organ reperfusion), mitochondrial function was measured. Hepatocytes stored in the complete L-15 solution were about 90% viable at the end of 48 hr of storage, while cells stored in a solution containing only the principle electrolytes (PE) lost viability (70% viable). Only the addition of a combination of divalent cations (Ca/Mg) and amino acids was sufficient to maintain viability equivalent to that obtained in the complete L-15 mixture. Hepatocytes suspended in L-15 maintained normal cell volumes (3.85 microliters/mg protein), while cells in the PE solution were swollen with cell volumes of 4.66 microliters/mg protein. Only the addition of Ca/Mg to the PE solution was effective at suppressing cell swelling similar to the complete L-15 media. Both basal and uncoupler-stimulated respiration were depressed in cells stored in the PE solution (15 and 28 nmol O2/min/mg protein) as compared to cells in L-15 (21 and 41 nmol O2/min/mg protein).(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Hypothermic preservation of hepatocytes. II. Importance of Ca2 and amino acids. 231 9

By shaking a dilute suspension of egg yolk with chloroform followed by low speed centrifugation (1500 g for 30 min) the water soluble proteins which include chicken IgG (IgY) separate from the emulsion of chloroform and lipophilic substances. The IgY may then be separated from the associated water soluble proteins by precipitation with 12% polyethylene glycol Mr 6000. The method called the chloroform - polyethylene glycol procedure was compared with the polyethylene glycol procedure which is currently being used. It was found that the chloroform - polyethylene glycol method yielded 2.57 times more IgY than the conventional polyethylene glycol method. The ratio of titres of IgY anti Jasus lalandii haemocyanin antibody purified by the two procedures was very nearly 2.57 indicating that the chloroform had no adverse effect on the antibody activity.
 ...
PMID:Isolation of IgY from the yolks of eggs by a chloroform polyethylene glycol procedure. 236 27

Hepatocytes from isolated rat livers were hypothermically incubated (5 degrees C) in an oxygenated environment with continuous shaking (to simulate organ perfusion preservation). The incubation solution was either a tissue culture medium (L-15), an organ preservation perfusate (UW gluconate), or a simple cold-storage solution used for organ preservation (UW lactobionate). Hepatocyte viability was assessed from the release of lactate dehydrogenase (LDH) into the incubation medium. Cell swelling (due to the uptake of water) was also measured. Within 24 hr, hepatocytes hypothermically stored in each of the three incubation solutions became swollen (30 to 40% water gain) and lost a significant amount of LDH (as much as 60%). The addition of polyethylene glycol (PEG; relative molecular mass 8000; 5 g%) to the solutions suppressed cell swelling and allowed the incubated hepatocytes to remain relatively well preserved (30% LDH release) for as long as 120 hr. Adding either dextran (relative molecular mass 10,000 to 78,000; 5 g%) or saccharides (100 mmol/liter) instead of PEG neither prevented cell swelling nor prevented the cells from dying. The results of this study suggest (i) there is a direct correlation (r = 0.873) between hypothermia-induced cell swelling and cell death (i.e., the suppression of cell swelling prevents cell death); (ii) the mechanism by which PEG prevents cell swelling (and thus maintains cell viability) is not related to the osmotic or oncotic properties of the molecule but instead is apparently related to some unknown interaction between PEG and the cell, an interaction that provides stability during hypothermic incubation; and (iii) hypothermia-induced cell swelling must be prevented if isolated hepatocytes are to be used as a model for studying the mechanism by which cell damage occurs during hypothermic organ preservation. By eliminating cell death due to cell swelling, the biochemical mechanisms of cell death can be studied.
 ...
PMID:Hypothermic preservation of hepatocytes. I. Role of cell swelling. 248 Aug 65

Ten isolates of Pseudomonas aeruginosa obtained from the corneas of patients with Pseudomonas keratitis adhered to soft contact lenses in significantly greater numbers than did six isolates from other body sites (P less than .05). However, there was no predominant serotype among the 10 corneal isolates tested. Isolates grown statically in broth at 37 degrees C formed a pellicle and adhered two times as much to contact lenses as did isolates grown in broth while shaking which did not form a pellicle (P less than .01). The more adherent isolates (grown at 37 degrees C) were shown to be more hydrophobic than the less adherent bacteria (grown at 26 degrees C) by their propensity to accumulate at the interface between hexadecane and saline and their movement into polyethylene glycol from dextran. These corneal isolates agglutinated erythrocytes, a process that was inhibited by dilute solutions (as low as 0.01%) of three commonly used surfactants. These same surfactants inhibited the adherence of Pseudomonas aeruginosa to soft contact lens surfaces by as much as 52%. It is concluded that hydrophobic interactions may significantly contribute to the ability of Pseudomonas aeruginosa to adhere to contact lenses.
 ...
PMID:The contribution of bacterial surface hydrophobicity to the process of adherence of Pseudomonas aeruginosa to hydrophilic contact lenses. 249 54

Isothermal gas chromatography with flame ionization detection was used to determine residual ethylene oxide (EtO), ethylene chlorohydrin, and ethylene glycol in soft rubber catheters that had been sterilized with EtO. Catheter samples were extracted by shaking with carbon disulfide, and the extract was analyzed on a 3% Carbowax 20M on 80-100 mesh Chromosorb 101 column, using nitrogen as the carrier gas. Ten replicate injections of a mixed standards solution gave coefficients of variation of 1.91, 1.23, and 4.74% for EtO, ethylene chlorohydrin, and ethylene glycol, respectively. A linear response was obtained with concentrations ranging from 1.0 to 7.9 micrograms EtO, 14.0 to 88.0 micrograms ethylene chlorohydrin, and 31.0 to 98.5 micrograms ethylene glycol. The proposed method detected as little as 0.5, 5.0, and 16.5 ng EtO, ethylene chlorohydrin, and ethylene glycol, respectively.
 ...
PMID:Rapid gas chromatographic determination of ethylene oxide, ethylene chlorohydrin, and ethylene glycol residues in rubber catheters. 401 75

The adhesion and growth of two pathogenic bacteria (Escherichia coli and Staphylococcus aureus) on the surface of a heparinized hydrophilic polymer were studied. Heparinized hydrophilic polymer is composed of poly(vinyl chloride) grafted with poly(ethylene glycol) monomethacrylate, diethylaminoethyl methacrylate, and ionically bound heparin. Poly(vinyl chloride) was used as a control. Plasma protein pre coated polymers were also prepared to evaluate the effect of proteins on bacterial adhesion. Polymer films were stored in bacterial suspensions under gentle shaking at 37 degrees C for 24 hr. The amount of adherent bacterial cells was measured by the bioluminescent assay of bacterial adenosine triphosphate. Their structure was observed by use of a scanning electron microscope. These evaluations demonstrated that a large amount of bacterial adhesion and biofilm formation was found on the surface of poly(vinyl chloride), whereas significant reductions in bacterial adhesion and no biofilm formation were observed on heparinized hydrophilic polymer. Bacterial adhesion onto plasma protein pre coat polymer films were also investigated, and it was clear that the bacterial adhesion on these surfaces was dependent upon the amount and species of absorbed proteins.
 ...
PMID:Inhibition of bacterial adhesion and biofilm formation by a heparinized hydrophilic polymer. 857 26

The aim of this work was to increase sensitivity in the detection of antigens from HIV-infected patients, through a process of immune complex dissociation without loss of antigenicity. 500 microliters of sera were mixed with 100 microliters of PEG 12%, stored one night in refrigerator, and centrifuged at 2000 g during 20 minutes. 200 microliters of buffer AcH/Ac- (pH 3.5) were added to the sediment, and incubated at 37 degrees C during one hour with periodic shaking. This was neutralized with 100 microliters of buffer TRIS/CIH (pH 8.6). The antigen was investigated in the original sample, supernatant and sediment. Samples of 105 patients with positive serology, confirmed by Western Blot following CDC criteria, were processed. The antigen was detected in 62 (59%) samples precipitated with PEG, but only 35 (33%) when conventional methods were used. Applying statistics X2: 13.97, P < 0.001, a highly significant association can be observed between PEG dissociation treatment and antigen detection. 27 negative sera by the standard method became positive in the whole sediment, and only 8 in the supernatant. In addition, 40 negative sera were processed, which had not become positive for the antigen by PEG treatment.
 ...
PMID:[Detection of human immunodeficiency virus antigen both free and in immune complexes]. 858 50

Cucurbita maxima trypsin inhibitor I (CMTI-I), a member of the squash-type protease inhibitor family, is composed of 29 amino acids and shows strong inhibition of trypsin by its compact structure. To study the structure-function relationship of this inhibitor using protein engineering methods, we constructed an expression system for CMTI-I as a fused protein with porcine adenylate kinase (ADK). A Met residue was introduced into the junction of ADK and CMTI-I to cleave the fusion protein with CNBr, whereas a Met at position 8 of authentic CMTI-I was replaced by Leu. Escherichia coli JM109 transformed with the constructed plasmid expressed the fused protein as an inclusion body. After cleavage of the expressed protein with CNBr, fully reduced species of CMTI-I were purified by reversed-phase HPLC and then oxidized with air by shaking. For efficient refolding of CMTI-I, we used 50 mM NH4HCO3 (pH 7.8) containing 0.1% PEG 6000 at higher protein concentration. Strong inhibitory activity toward trypsin was detected only in the first of three HPLC peaks. The inhibitor constant of CMTI-I thus obtained, in which Met8 was replaced by Leu, was 1.4 x 10(-10) M. The effect of replacement of Met with Leu at position 8 was shown to be small by comparison of the inhibitor constant of authentic CMTI-III bearing Lys at position 9 (8.9 x 10(-11) M) with that of its mutant bearing Leu at position 8 and Lys at position 9 (1.8 x 10(-10) M). To investigate the role of the well conserved hydrophobic residues of CMTI-I in its interaction with trypsin, CMTI-I mutants in which one or all of the four hydrophobic residues were replaced by Ala were prepared. The inhibitor constants of these mutants indicated that those with single replacements were 5-40 times less effective as trypsin inhibitors and that the quadruple mutant was approximately 450 times less effective, suggesting that the hydrophobic residues in CMTI-I contribute to its tight binding with trypsin. However, each mutant was not converted to a temporary inhibitor.
 ...
PMID:Synthesis of a squash-type protease inhibitor by gene engineering and effects of replacements of conserved hydrophobic amino acid residues on its inhibitory activity. 901 Sep 39

Ashbya gossypii can grow on triacyglycerol as carbon source. A degradation rate of 0.05 g x g-1 mycelial dry mass x h-1 was detected for soybean oil. Although this rate was within the sensitivity range of lipase assays no activity was detectable. On the other hand, extracellular lipase activity could be visualized by clearance halos round the growing mycelium when trioleoylglycerol was emulsified as the sole carbon source in agar plates. Variation of the culture conditions revealed that reduced shaking speed and decreased fat content in the medium led to detectable amounts of lipase in the supernatant of flask cultures. A maximal activity of 800 U x l-1 was obtained after 32 h of cultivation in flasks containing 1% yeast extract and incubated at 60 rpm. Because of its pI of 9.0, the enzyme could be purified in a single step by preparative isoelectric focusing. It appeared as a homogeneous protein in analytical isoelectric focusing and SDS/PAGE (M 35,000). The lipase was inactivated within minutes in stirred gas/water, trioleoylglycerol/water or oleic acid/water mixtures. These effects suggested an interface inactivation. This idea was supported by a stability modulation observed with the surfactant Pluronic F-68. Inactivation by oleic acid led to an aggregation of the lipase shown by gel filtration. Growth experiments performed under lipase-stabilizing conditions revealed a negative influence of glucose, glycerol or oleic acid on detectable lipase activity, probably due to a regulation of lipase formation. Inactivation and regulation thus explained the lack of detectable lipase activity in cultures of A. gossypii growing on triacylglycerol.
 ...
PMID:Regulation and properties of a fungal lipase showing interfacial inactivation by gas bubbles, or droplets of lipid or fatty acid. 906 67


1 2 3 4 5 Next >>