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At least 973 records · Page 54Linked to original sources
PubMed1980

Antibody-mediated polysome precipitation as a method for the size determination of viral mRNA species: viral envelope glycoprotein mRNA of avian sarcoma viruses.

A method was developed that allows the in situ isolation of viral mRNA, i.e. from polysomes of infected cells. This was achieved by precipitating intact polysomes via their nascent virus polypeptides using virus-specific antibodies. As a model, antibodies to the major envelope glycoprotein (gp85) of avian sarcoma viruses were employed to precipitate those polysomes from infected cells which synthesized the corresponding p70 virus glycoprotein precursor. Normal immunoglobulin and polysomes from uninfected chicken embryo fibroblasts served as controls. The radioactivity labelled mRNA from antibody-precipitated polysomes could subsequently be extracted and characterized for size. It was found that avian sarcoma virus gp85 envelope glycoprotein is predominantly synthesized by a 22--28 s viral mRNA. In addition, minor amounts of gp85-specific mRNAs of 16--21 s and 28--35 s could be demonstrated. The data indicate the presence in polysomes of viral mRNA species coding for i) gp85 only (16--21 s RNA), ii) gp85 and pp60src protein from the adjacent src-gene (22--28 s RNA), and iii) a large viral precursor protein (28--35 s RNA).

Animals↗
PubMed1989

Selective separation of virus proteins and double-stranded RNAs by SDS-KCl precipitation.

The total viral structural polypeptides and the double-stranded genomic RNAs of bluetongue virus can be selectively separated by a single SDS-KCl precipitation step. This simple, rapid and highly reproducible method enables greater than 95% recovery and purity of both viral proteins and dsRNAs within 30 min. The serotypic identity of the separated dsRNAs can be analyzed by SDS-PAGE electrophorogram immediately. After a single phenol/chloroform extraction, the dsRNA can also be used as hybridization probes, templates for molecular cloning and direct RNA sequencing. The SDS-KCl-precipitated viral proteins could be used readily for peptide mapping and as immunogens. Polyclonal and monoclonal antibodies raised against SDS-KCl-precipitated viral structural polypeptides were useful in Western immunoblots.

Blotting, Northern↗
PubMed1994

Affinity precipitation of trypsin with soybean trypsin inhibitor linked Eudragit S-100.

Soybean trypsin inhibitor linked to Eudragit S-100 was used for the affinity precipitation of trypsin. Polymer and ligand concentrations used in conjugate preparation showed remarkable effect on the trypsin recovery. Trypsin precipitation efficiency amounted to 89% and recovery was 74%. The final purification of relatively crude commercial trypsin resulted in 1.85-fold purification. The SDS-PAGE analysis indicated significant purification. The precipitated enzyme activity was around 96% and recovered enzyme activity was 83%.

Acrylic Resins↗
PubMed1986

Evaluation of the polyethylene glycol precipitation method for the estimation of chicken high density lipoprotein cholesterol.

A neutral polymer precipitation procedure using polyethylene glycol 6000 (PEG) for fractionation of chicken plasma lipoproteins was optimized. Lipoprotein precipitation was dependent on PEG concentration and pH but was independent of PEG exposure time. A PEG concentration of 100 g/l (pH 8) precipitated chicken plasma very low density (VLDL) and low density (LDL) lipoproteins. Disc electrophoresis of supernates demonstrated that high density lipoprotein (HDL) was retained and LDL eliminated by PEG treatment of plasma. Gel filtration chromatography of whole plasma and PEG-treated supernatants on Bio-Gel A-5m demonstrated that HDL-cholesterol content of supernates was unchanged by PEG exposure, while VLDL-cholesterol was selectively removed.

Animals↗
PubMed2004

Electrochemically assisted co-precipitation of protein with calcium phosphate coatings on titanium alloy.

A bovine serum albumin protein-containing calcium phosphate coating (BSA/brushite) was prepared by electrochemically assisted co-precipitation onto a hydroxyapatite (HA) coated Ti-6Al-4V surface. Electrochemically assisted co-precipitation of BSA/brushite coatings onto HA resulted in a 70-fold increase in BSA inclusion compared to simple adsorption, and was subsequently released by a slower mechanism (15% loss over 70 h). Thus, this electrochemically assisted co-precipitation technique provides an efficient method of protein incorporation at physiological temperature, with a potential for sustained release of therapeutic agents as may be required for metallic implant fixation.

Adsorption↗
PubMed2004

Screening of antifungal agents using ethanol precipitation and bioautography of medicinal and food plants.

In the search for bioactive compounds, bioautography and ethanol precipitation of macromolecules (proteins, polysaccharides, etc.) of plant aqueous extracts were associated in an antifungal screening. Thus, the supernatants, precipitates (obtained by ethanol precipitation) and aqueous extracts were investigated of medicinal and fruit bearing plants used against skin diseases by the Brazilian population. The agar diffusion and broth dilution methods were used to assess the activity against three fungi: Candida albicans, Trichophyton rubrum and Cryptococcus neoformans. The results, evaluated by the diameter of the inhibition zone of fungal growth, indicate that six plant species, among the 16 investigated, showed significant antifungal activity. The minimal inhibitory concentration (MIC) was determined on plant extracts that showed high efficacy against the tested microorganisms. The most susceptible yeast was Trichophyton rubrum and the best antifungal activity was shown by Xanthosoma sagittifolium supernatant. The bioautography was performed only for the aqueous extracts and supernatants of those plants that showed antifungal activity against Candida albicans and Cryptococcus neoformans, using n-butanol/acetic acid/water (BAW) 8:1:1 to develop silica gel TLC plates. Clear inhibition zones were observed for aqueous extracts of Schinus molle (R(f) 0.89) and Schinus terebinthifolius (R(f) 0.80) against Candida albicans, as for supernatant of Anacardium occidentale (R(f) 0.31) against Cryptococcus neoformans. The separation of macromolecules from metabolites, as in the case of Anacardium occidentale, Solanum sp. and Xanthosoma sagittifolium, enhances antifungal activity. In other cases, the antifungal activity is destroyed, as observed for Momordica charantia, Schinus molle and Schinus terebinthifolius.

Animals↗
PubMed2005

Heavy metal precipitation by polycation-polyanion complex of PEI and its phosphonomethylated derivative.

The removal of various heavy metal ions such as Cu2+, Co2+, Zn2+, Ni2+ and Pb2+ from aqueous solutions by precipitation with polyelectrolyte complex of PPEI and PEI was conducted. Heavy metal binding with PPEI was initially allowed to occur and then upon equilibration, PEI was added to initiate precipitation of the polyelectrolyte complex together with the heavy metal ion. The PPEI-PEI system was found effective for heavy metal scavenging purposes even in the presence of high concentrations of non-transition metal ions like Na+. Heavy metal concentration may be reduced beyond emission standards for industrial wastewaters. The PPEI-PEI polyelectrolyte complex was found to be more effective than traditional precipitation methods for the treatment of a representative electroless Ni plating waste solution.

Chemical Precipitation↗
PubMed2006

Enhancing struvite precipitation potential for ammonia nitrogen removal in municipal landfill leachate.

This study was conducted to improve struvite precipitation for NH4-N removal purpose in landfill leachate. For this purpose, we evaluated the effect of the feeding sequence of precipitating reagents (magnesium, orthophosphate, and buffering reagent) on NH4-N removal by forming struvite deposits. Struvite precipitation effectively proceeded by an addition of excess magnesium and phosphate sources followed by an addition of the buffering reagent, in which condition the local formation of inappropriate deposits or the contamination of the desired struvite was minimized. We also tested the effect of struvite addition as the seeding materials on NH4-N removal. Seed addition would increase the potential for the struvite crystal growth, which enhanced NH4-N removal performance in landfill leachate treatment.

Ammonia↗
PubMed2024

ZASP: A Highly Compatible and Sensitive ZnCl2 Precipitation-Assisted Sample Preparation Method for Proteomic Analysis.

Universal sample preparation for proteomic analysis that enables unbiased protein manipulation, flexible reagent use, and low protein loss is required to ensure the highest sensitivity of downstream liquid chromatography-mass spectrometry (LC-MS) analysis. To address these needs, we developed a ZnCl2 precipitation-assisted sample preparation method (ZASP) that depletes harsh detergents and impurities in protein solutions prior to trypsin digestion via 10 min of ZnCl2 and methanol-induced protein precipitation at room temperature (RT). ZASP can remove trypsin digestion and LC-MS incompatible detergents such as SDS, Triton X-100, and urea at high concentrations in solution and unbiasedly recover proteins independent of the amount of protein input. We demonstrated the sensitivity and reproducibility of ZASP in an analysis of samples with 1 μg to 1000 μg of proteins. Compared to commonly used sample preparation methods such as SDC-based in-solution digestion, acetone precipitation, FASP, and SP3, ZASP has proven to be an efficient approach. Here, we present ZASP, a practical, robust, and cost-effective proteomic sample preparation method that can be applied to profile different types of samples.

Proteomics↗
PubMed2005

Comparative field study on precipitation, throughfall, stemflow, fog water, and atmospheric aerosol and gases at urban and rural sites in Japan.

Precipitation collected by a wet-only sampler (WP), precipitation collected by a filtering-type bulk sampler (BP), throughfall (TF), stemflow (SF), fog water (FW), and atmospheric aerosol and gases were collected at two sites with different site classifications: an urban site (Mt. Rokko) and a rural site (Mt. Awaga) to investigate canopy-atmosphere interactions and to study the chemistry of precipitation in forested areas located in different atmospheric conditions. Compared to those at the rural site, the monthly volume-weighted pH values at the urban site were not significantly (p>0.05) different for WP, higher (p<0.05) for BP, not significantly (p> 0.05) different for TF, lower (p<0.01) for SF, and lower (p<0.01) for FW. The order of mean pH values at the urban site was FW<SF<WP<TF<BP. In contrast, the order at the rural site was FW<SF<BP<WP<TF. Concentrations of chemical species at the urban site were higher than those at the rural site in all samples and all chemical species. In particular, higher NO(3)(-) concentrations at the urban site were observed in all samples. The amount of dry deposition on leaves at the urban site was approximately 1.17 times larger than that at the rural site. The monthly net TF (=TF-BP) in autumn seemed to be larger than that in summer; this trend was remarkable in K(+). The monthly NO(3)(-) deposition in the net TF was larger at the urban site than at other parameters and at the rural site. The concentrations of chemical species in aerosol and gases that were measured near the central part of Kobe City were ca. 3.4 times higher than those in the rural area. Mt. Rokko borders the central part of the city, which caused the concentrations at Mt. Rokko to be higher than those at Mt. Awaga. The deposition amounts at Mt. Rokko were larger than those at Mt. Awaga, which probably can be attributed to the higher concentrations of chemical species in atmospheric aerosol and gases.

Aerosols↗
PubMed2003

Adhesion of in situ precipitated calcium carbonate in the presence and absence of magnetic field in quiescent conditions on different solid surfaces.

Deposition of in situ precipitated calcium carbonate from Na(2)CO(3) and CaCl2 solutions on different substrates, i.e. stainless steel, copper, aluminium, and glass, was investigated at different temperatures, 20 degrees C, 40 degrees C, 60 degrees C and 80 degrees C, both in the absence and presence of S-S 0.1T magnetic field (MF). It was found that in quiescent conditions during 2h the amounts deposited firmly on the surfaces decreased with increasing temperature. If MF was present the deposition was reduced at all temperatures, and depended on the nature of the substrate. The largest MF effect was found on glass at 60 degrees C, which amounted 50% reduction of the deposit. However, at 80 degrees C no deposition was found in the presence of MF on aluminium surface. At this temperature the reproducibility of the experiments was poor, and an additional effect due to the metal surface corrosion (especially that of aluminium and copper) may be thought in alkaline environment of the experiments (pH ca. 10). Based on optical microscope photographs, it was concluded that the amounts of crystallographic forms of CaCO3 depended on the nature of substrate on which the precipitation and then the adhesion took place. To some extent the ratios of CaCO3 forms precipitated were different in the bulk phase than on the substrate surfaces at the same temperature, and this conclusion was based on the X-ray diffractograms. Some possible mechanisms causing MF effects are discussed.

Aluminum↗
PubMed2003

Effect of freeze-thaw process on partitioning of contaminants in ferric precipitate.

The primary interest of this work was to determine the processing conditions which will provide the most water removal from the precipitate after freezing and thawing. The work examined the effect of variables such as freezing time, freezing temperature, and pre-treatment steps, e.g. agitation or concentration, on the freeze thaw process of ferric precipitates. The extent of dewatering of freeze thawed samples was not significantly affected by freezing rate or curing time, provided the floc was completely frozen. However, a pre-concentration step was found to produce a more concentrated residual. The relatively low degree of structure within the ferric flocs makes them particularly suitable for freeze-thaw conditioning. Only a slight increase in leach out of contaminant from the floc was observed. Thus, the experiments indicate that this is a very simple and effective method of dewatering precipitates, which does not require the use of additional additives.

Chemical Precipitation↗
PubMed2006

Cognition-induced epilepsy associated with specific emotional precipitants.

A 32-year-old woman with primary generalized epilepsy described absence events precipitated by talking about childhood sexual abuse, her epilepsy, or her father's difficulties with schizophrenia. She was referred for assessment of suspected psychogenic nonepileptic events. During simultaneous video/EEG monitoring, 30 absence seizures were recorded, 28 of which occurred while discussing one of these three specific precipitants. No nonepileptic events were seen. This finding highlights the importance of thorough investigation of ambiguous events, and confirms that specific emotional precipitants can induce seizures in susceptible people with epilepsy.

Adult↗
PubMed1986

Precipitation of the D-galactose specific lectin from Erythrina indica by a triantennary complex type oligosaccharide.

We have previously demonstrated that a high mannose type glycopeptide is bivalent for binding Concanavalin A (Con A) and can precipitate the lectin (Bhattacharyya L. and Brewer, C.F. (1986) Biochem. Biophys. Res. Commun. 137, 670-674). The present results show that a triantennary complex type oligosaccharide containing nonreducing terminal galactose residues can precipitate the D-galactose/N-acetyl-D-galactosamine specific lectin from Erythrina indica (EIL). The interactions of the oligosaccharide with EIL was investigated by quantitative precipitin analysis. The equivalence point of the precipitin curve indicated that the glycopeptide is trivalent for EIL binding. These results indicate that each arm of the oligosaccharide can independently bind separate lectin molecules leading to precipitation of the complex. These findings are discussed in terms of the possible biological structure-function properties of complex type oligosaccharides.

Acetylgalactosamine↗
PubMed1996

Dielectric constant and ionic strength effects on DNA precipitation.

We have investigated the effect of different zwitterionic compounds on DNA precipitation induced by spermine4+. Glycine, beta-alanine, 4-aminobutyric acid, and 6-aminocaproic acid have shown an increasing capacity to attenuate DNA precipitation. This protection effect has been correlated with the dielectric constant increase of their corresponding solutions. Calculations based on these experimental data and counter-ion condensation theory have confirmed the importance of this parameter for DNA-ion interactions and precipitation mechanisms. We have also observed a resolubilization of DNA in the presence of 6-aminocaproic acid at high spermine4+ concentration and in the presence of glycine at high spermidine3+ concentration. This could be explained by an increase of screening effect with polyamine concentration.

Aminocaproic Acid↗
PubMed1998

Precipitation of DNA by polyamines: a polyelectrolyte behavior.

Conditions of double-stranded DNA precipitation by the polyamines spermidine and spermine have been determined experimentally and compared to theoretical predictions. The influence of the concentrations of DNA and added monovalent salt, and of the DNA length has been investigated in a systematic manner. Three regimes of DNA concentrations are observed. We clarify the dependence of these regimes on the monovalent salt concentration and on the DNA length. Our observations make possible a rationalization of the experimental results reported in the literature. A comparison of the precipitation conditions of different kinds of polyelectrolytes suggests a general process. Our experimental data are compared to the "ion-bridging" model based on short-range electrostatic attractions. By starting from the spinodal equation, predicted by this model, and using the limiting form of Manning's fractions of condensed counterions, analytical expressions of the precipitation conditions have been found in the three regimes. Experimental and theoretical results are in good agreement.

Animals↗
PubMed1975

Radioimmunoassay for triiodothyronine: use of polyethylene glycol to precipitate immune complexes.

1. A rapid radioimmunoassay (RIA) for determining serum triiodothyronine (T3) concentration has been developed. The reaction of T3 with its antibody was performed at 37 degrees C for 3 hours; precipitation of antibody bound T3 by 15% polyethylene glycol (PEG) was done at ice-bath temperatures. 2. The effects of pH on the interaction of T3 with its antibody and on the precipitation of antibody gamman globulin by PEG are discussed. 3. PEG precipitates and supernatants were characterized by immunoelectrophoresis and polyacrylamide gel electrophoresis. 4. The RIA has a between run precision of 9.3% at a mean T3 concentration of 179 ng/dl. The recovery of 50 or 100 ng/dl T3 was 95-102% and the normal range estimate was 66-215 ng/dl (N equal to 49).

Anilino Naphthalenesulfonates↗
PubMed1986

Presence of unsedimented precipitate in visually non-turbid supernates in the heparin-manganese method for HDL-cholesterol quantitation.

An inherent problem with the heparin-manganese precipitation procedure for high density lipoprotein-cholesterol (HDL-C) quantitation is the inability to sediment all the precipitated lipoproteins, especially in hypertriglyceridemic samples. This results in overestimation of HDL-C. Thus ultrafiltration has been recommended for turbid supernates. We have investigated 47 non-turbid supernates for possible presence of unsedimented precipitate. Optical turbidity in these samples was found to correlate with the serum triglyceride level. With ultrafiltration of the supernates, there was a significant decrease in cholesterol, optical turbidity and apoprotein A-I. The percent change in turbidity correlated with the percent change in cholesterol. There was also correlation between percent change in cholesterol and the prefiltration supernate turbidity. These results indicate that visually clear supernates may show optical turbidity; the turbidity is likely due to triglyceride-rich particles, which contain cholesterol; the fall in cholesterol with ultrafiltration is due to removal of these floating particles and some adsorbance of HDL particles to the filters.

Apolipoprotein A-I↗