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PubMed1982

[Experiences in serological diagnosis of tuberculosis].

Serological tests complete clinical diagnosis of tuberculosis. Passive hemagglutination and passive hemolysis are of greater usefulness than complement fixation, precipitations, flocculation or agglutination reactions. Antiglobulin technique and combination of several tests are of value. False negative results in cases of tuberculosis and healthy persons serologically false positive are still a problem. New tests with standardized purified polysaccharide, phosphatide and protein are expected to be of value in future.

Agglutination Tests↗
PubMed1961

Immunologic studies of heart tissue. IV. Serologic reactions with human heart tissue as revealed by immunofluorescent methods: isoimmune, Wassermann, and autoimmune reactions.

Reactions of normal and pathologic sera with heart tissue have been investigated by the immunofluorescent method, with particular reference to presumptive autoantibodies to heart and their differentiation from blood group isoantibodies and Wassermann antibody. In the heart, blood group substances A and B were found distributed in capillary walls, vascular endothelium, and interstitial connective tissue. In surveys of randomly selected sera, isoimmune reactions against tissue blood group substances A and B were noted infrequently. This finding was considered related to the limited sensitivity of fluorescent antibody methods. Heart tissue from blood group O individuals was used for screening of pathologic sera for presence of tissue-reactive factors. Wassermann antibody was found reactive with constituents of myocardial sarcoplasm, of which the major reactant was cardiolipin. Wassermann-positive sera absorbed with beef cardiolipin gave evidence of reaction with other constituents of myofiber sarcoplasm. Sera of patients with rheumatic fever, rheumatic heart disease, rheumatoid arthritis, disseminated lupus, and liver disease frequently showed a marked reactivity with constituents of myofiber sarcoplasm. These serum factors were differentiated from Wassermann antibody. At least three patterns of immunofluorescent staining could be differentiated by the distribution of reactants in the myofiber sarcoplasm. These reactants were extractable with ethanol and methanol but not by acetone. Sera found reactive by immunofluorescence frequently gave positive flocculation and complement-fixation tests with alcohol extracts of human heart. Immunofluorescent tests were best correlated with flocculation reactions. Sarcoplasmic-reactive factors were associated in some sera with 19S gamma globulin as demonstrated by the use of fluorescent anti-19S gamma globulin. Serologic reactions with homologous or autologous heart were observed particularly frequently with sera from rheumatic patients approximately 2 weeks following cardiac surgery, as well as in some non-rheumatic patients following cardiac or thoracic surgery or acute myocardial infarction. The pathogenetic significance of these presumptive autoantibodies to heart is unknown. As yet, no definite conclusions may be drawn regarding their relationship to bound gamma globulin in rheumatic hearts or to the postcardiotomy and post-infarction syndromes.

Antibodies↗
PubMed1990

False-negative syphilis screening: the prozone phenomenon, nonimmune hydrops, and diagnosis of syphilis during pregnancy.

The prevalence of congenital syphilis is rapidly rising in several areas of the United States. Efforts to control the disease depend on the effectiveness of established screening strategies and treatment of infected pregnant women. False-negative test results hinder these efforts and leave the fetus at risk for acquiring congenital syphilis. Recently we encountered four cases of false-negative syphilis serologic results in women who gave birth to infants with congenital syphilis. The false-negative results were caused by the prozone phenomenon. The prozone phenomenon, seen during primary and secondary syphilis, occurs because a higher than optimal amount of antibody in the tested sera prevents the flocculation reaction typifying a positive result in reagin tests. Serum dilution is necessary to make the correct diagnosis. We recommend that for any pregnant woman with apparently negative syphilis serologic results in whom fetal compromise of unknown etiology exists, particularly nonimmune hydrops, nontreponemal testing should be repeated using serum dilutions to prevent a missed diagnosis of syphilis. We further recommend serum dilution as a routine procedure for all pregnant women in areas of high syphilis prevalence.

Adult↗
PubMed1996

Structure of the phosphopeptidomannans from flocculent and non-flocculent yeast Kluyveromyces lactis.

After extraction from whole cells, and purification by gel filtration, the chemical composition and molecular mass estimation of the cell-wall phosphopeptidomannan (PPM) showed no significant difference respectively between flocculent, weakly, very weakly and non-flocculent Kluyveromyces lactis yeast strains. However, when PPMs were tested as ligands of a lectin, extracted from the flocculent strain, the PPM isolated from the flocculent and weakly flocculent strain were recognized to a higher degree than those isolated from the non and very weakly flocculent strains. Acetolysis of PPM extracted from the four strains produced five oligosaccharide fractions corresponding to mono-, di-, tri-, penta-and hexa-saccharides. The flocculent strain was characterised by a high content of di-and penta-saccharides. The 1H NMR analysis of the oligosaccharides demonstrated that the flocculent strain contained equivalent levels of the two mannobioses: Man(alpha 1-->2)Man and Man(alpha 1-->3)Man and of the two mannotrioses Man(alpha 1-->2)Man(alpha 1-->2)Man and Man(alpha 1-->3)Man(alpha 1-->2)Man. In contrast, the non-flocculent and the very weakly flocculent strains contained a single type of mannobiose Man(alpha 1-->2)Man and one type of mannotriose Man(alpha 1-->2)Man(alpha 1-->2)Man.

Acetylglucosamine↗
PubMed2004

Nano silica removal from IC wastewater by pre-coagulation and microfiltration.

Microfiltration (MF) coupled with pretreatment by coagulation was adopted in the treatment of chemical mechanical polishing (CMP) wastewater from IC manufacturing plants, containing high concentrations of silica. Poly-aluminium chloride (PACl) was the coagulant, while the cationic polyacrylamide (PAA) was the flocculant aid. Preliminary tests were performed with the raw CMP wastewater in order to determine the optimal coagulation condition for subsequent microfiltration. Analysis of the particle size distribution shows that nearly all silica particles were enlarged from nano scale to at least 4 microm in diameter after the pre-treatment. The pre-treated wastewater was then filtered through a polytetrafluoroethylene (PTFE) membrane with a pore size 0.5 microm at a constant vacuum pressure. Trace amounts of PAA in addition to the PACl coagulation can effectively increases the permeate flux.

Acrylic Resins↗
PubMedDate not supplied

Echinococcosis in Egypt: IV. Serology on patients with chest problems.

Patients complaining of chest disorders were clinically and serologically examined for evidence of echinococcal infection. Serologically, the patients were screened by the indirect haemagglutination test and reactors were confirmed by the bentonite flocculation and/or latex-agglutination tests. Of 755 patients 6.2 percent had echinococcal antibodies in their sera. Of 393 patients given a chest radiography one patient (0.25%) had distinct pulmonary hydatid cysts. The bentonite flocculation technique picked more of the positives (91.5%) than did the latex-agglutination (14.9%) technique. Females were more exposed to echinococcal infection (8.4%) than males (2.3%). Among positives, 71-75 per cent were below thirty years old. Prevalence of infection was higher among individuals having direct contact with dogs (4.6%) than among individuals with no direct contact with dogs (3.2%). Evidently cross-reactions between the echinococcal antigen and antibodies of some bacterial and parasitic infections including schistosomiasis interfere with the haemagglutination test results.

Adult↗
PubMed1998

Discrimination between ethanol inhibition models in a continuous alcoholic fermentation process using flocculating yeast.

Discrimination between different rival models for describing the inhibitory effect of ethanol both on yeast growth and on fermentation was studied for a continuous process of alcoholic fermentation in a tower reactor with recycling of flocculating cells. Models tested include linear, parabolic, hyperbolic, exponential, and generalized nonlinear power-law types. The best expressions were identified under the criteria that all the kinetic parameters should assume acceptable values in a feasible range and should result in the best fit of the experimental data. The kinetic parameters were estimated from steady-state data of several sugar concentrations in feeding stream (S0 = 160, 170, 180, 190, 200 g/L), constant dilution rate (D = 0.2 h-1), recycle ratio (alpha = 13.6), and temperature (T = 30 degrees C). The best model for the yeast growth was of power-law type, whereas for the product formation the best model was of linear type. These models were able to reproduce the trends of the process variables satisfactorily.

Ethanol↗
PubMed2000

Characterization of landfill leachates and studies on heavy metal removal.

This study covers a thorough characterisation of landfill leachates emerging from a sanitary landfill area. The landfill leachates were obtained in the acidic stage of landfill stabilisation. Their organic content was high as reflected by the high BOD5 (5 day biological oxygen demand) and COD (chemical oxygen demand) values. They were also highly polluted in terms of the parameters TKN (total Kjeldahl nitrogen), NH4-N, alkalinity, hardness and heavy metals. Nickel was present in these wastewaters at a significant concentration. With regard to the high heavy metal content of these wastewaters, several physicochemical removal alternatives for the heavy metals Cu, Pb, Zn, Ni, Cd, Cr, Mn and Fe were tested using coagulation, flocculation, precipitation, base addition and aeration. Additionally, COD removal and ammonia stripping were examined. Co-precipitation with either alum or iron salts did not usually lead to significantly higher heavy metal removal than lime alone. The major methods leading to an effective heavy metal removal were aeration and lime addition. Nickel and cadmium seemed to be strongly complexed and were not removed by any method. Also lead removal proved to be difficult. The results are also discussed in terms of compliance with standards.

Environmental Monitoring↗
PubMed2004

Floc characterisation by analysis of laser beam attenuation.

The continuous growth in the demand of good quality water for different purposes makes the control of environmental pollution a matter for public and official concern. The monitoring of particles for quality control of water or wastewater treatment is becoming important and the need for the development of control devices is increasing. The purpose of this work was to develop a photosedimentation method for floc characterization combining gravitational settling with photoelectric measurements. Settling particles cross a light beam that illuminates a detection system. The attenuation of the beam is related to the projected area of the particles and so the particle size distribution can be determined. When a floc crosses the beam, the amount of light reaching the detector is reduced. Voltage/time signals are analyzed in order to produce the physical characteristics of flocs such as size and density. Different light sources and detection systems were tested in calibration tests and afterwards flocculated suspensions were used for experimental analysis. Floc characteristics could then be related to the experimental conditions of floc formation (mixing conditions and polymer concentration). With the experience acquired, a prototype was designed and implemented, being capable of operating in laboratory or field conditions.

Environmental Monitoring↗
PubMed1990

Expression of the HTLV-I tax transactivator in yeast: correlation between phenotypic alterations and tax function in higher eukaryotes.

The transcriptional activator protein (Tax) from human T-cell leukemia virus type 1 was expressed in yeast using several different promoters in several strains: In all instances, expression of Tax resulted in very strong aggregation of the yeast cells. This phenotype appears to be identical by all criteria tested to the flocculation phenotype of the dominant mutation flo 1. Of most significance, mutations in Tax that affect transactivation of the IL-2R alpha regulatory sequences, but retain their ability to activate the viral long terminal repeat also fail to yield the aggregation phenotype. Based on these findings, expression of Tax in yeast may prove to be a simple primordial system for examining the regulatory mechanisms and cellular functions involved in regulation of gene expression.

Gene Products, tax↗
PubMed1984

Comparison of gel filtration and ammonium sulphate precipitation in the purification of diphtheria toxin and toxoid.

Crude diphtheria toxin and toxoid were subjected to purification by gel filtration and stepwise ammonium sulphate precipitation. The various fractions obtained by the purification procedures were studied by immunological methods. A high molecular weight fraction of glycoprotein nature was present in all of the crude preparations studied. The fraction was antigenically non-identical with the real toxin or toxoid and did not have its origin in the culture medium. It showed a long flocculation time when tested against equine diphtheria toxoid antiserum. The fraction could be removed from the crude preparations by gel filtration or by precipitation with 21% (w/v) ammonium sulphate. When comparing toxoids purified by each of these methods, the method of gel filtration resulted in a somewhat higher degree of purity, suggesting that this method would be more suitable than the AS precipitation method for the purification of diphtheria toxoid.

Ammonium Sulfate↗
PubMed2001

Surface Chemical Studies on Sphalerite and Galena Using Bacillus polymyxa.

The interaction of sphalerite and galena with cells of Bacillus polymyxa was investigated through adsorption, electrokinetic, flotation, and flocculation studies. Adsorption experiments indicated that a higher amount of the cells was adsorbed onto galena compared to sphalerite. The adsorption density of the cells onto galena was almost independent of pH while that onto sphalerite was found to continuously decrease with increasing pH. The adsorption isotherms of the bacterial cells on galena and sphalerite exhibited Langmuirian behavior. Electrokinetic measurements showed that the negative electrophoretic mobilities of the cells were reduced in magnitude in proportion to the time of interaction with either sphalerite or galena. Similar trends were observed in the cases of sphalerite and galena after interaction with the cells. However, the magnitude of the reduction in the electrophoretic mobilities was found to be greater for galena than for sphalerite. Flotation tests revealed that galena was almost completely depressed after interaction with the cells both in the absence and in the presence of the collector. In contrast, the addition of collector and activator to sphalerite, which was initially interacted with the cells, restored the floatability at and beyond pH 8.5. Selective flotation tests on a synthetic mixture of galena and sphalerite confirmed that sphalerite could be preferentially floated from galena, which was depressed by the bacterial cells. Selective flocculation tests further demonstrated that galena could be flocculated from sphalerite, which was dispersed in the presence of cells of B. polymyxa at pH 9-9.5. Copyright 2001 Academic Press.

Journal Article↗
PubMed2002

Surface chemical studies on sphalerite and galena using extracellular polysaccharides isolated from Bacillus polymyxa.

Adsorption, electrokinetic, microflotation, and flocculation studies have been carried out on sphalerite and galena minerals using extracellular polysaccharides (ECP) isolated from Bacillus polymyxa. The adsorption density of ECP onto galena is found to be higher than that onto sphalerite. The adsorption of ECP onto sphalerite is found to increase from pH 3 to about pH 7, where a maximum is attained, and thereafter continuously decreases. With respect to galena, the adsorption density of ECP steadily increases with increased pH. The addition of ECP correspondingly reduces the negative electrophoretic mobilities of sphalerite and galena in absolute magnitude without shifting their isoelectric points. However, the magnitude of the reduction in the electrophoretic mobility values is found to be greater for galena compared to that for sphalerite. Microflotation tests show that galena is depressed while sphalerite is floated using ECP in the entire pH range investigated. Selective flotation tests on a synthetic mixture of galena and sphalerite corroborate that sphalerite could be floated from galena at pH 9-9.5 using ECP as a depressant for galena. Flocculation tests reveal that in the pH range 9-11, sphalerite is dispersed and galena is flocculated in the presence of ECP. Dissolution tests indicate release of the lattice metal ions from galena and sphalerite, while co-precipitation tests confirm chemical interaction between lead or zinc ions and ECP. Fourier transform infrared spectroscopic studies provide evidence in support of hydrogen bonding and chemical interaction for the adsorption of ECP onto galena/sphalerite surfaces.

Bacillus↗