Increased erythropoietin production in children with severe malarial anemia.

Plasma immunoreactive erythropoietin concentrations were determined in 84 children with Plasmodium falciparum malaria in Gabon. There was an inverse log/linear relationship between hemoglobin or hematocrit and plasma erythropoietin, indicating that erythropoietin levels increased exponentially as circulating hemoglobin decreased. These result show that P.

[Microbiological diagnosis of malaria and amoebiasis].

All stages of malaria and amebiasis may be sensitively and specifically diagnosed by means of microbiological methods. Microscopical parasitology holds a key position when supplemented by immunodiagnostic assays. Molecular biology techniques are currently still inferior to the above procedure.

Isolation of an immunodiagnostic Taenia solium coproantigen.

Antigens of Taenia solium can be demonstrated by ELISA technique in stool samples of tapeworm carriers. In order to isolate these immunodiagnostic components from stool, fecal samples of known T. solium carriers were subject to chromatographic purification procedures: immunoaffinity chromatography and a subsequent two-step high performance liquid chromatography yielded a 60-kDa protein that was shown to react in a Western blot with polyclonal anti-T.

Detection of Bartonella bacilliformis in cultures, blood, and formalin preserved skin biopsies by use of the polymerase chain reaction.

A polymerase chain reaction (PCR) is described for the detection of Bartonella bacilliformis, the etiologic agent of bartonellosis, which cannot be identified biochemically. Amplification of a genomic 231 bp Bartonella DNA sequence permitted specific identification of 12 Bartonella isolates from Peruvian bartonellosis patients as well as detection of Bartonella DNA in blood samples and formaldehyde preserved skin biopsies. Specificity of amplification products was confirmed by restriction fragment analysis.

Detection of Taenia solium antigens in merthiolate-form preserved stool samples.

Cysticercosis can be controlled by mass treatment of Taenia solium carriers in hyperendemic areas. An automated screening method suitable for mass application is required to determine the prevalence of taeniasis and the efficacy of its treatment, since existing methods of carrier detection are considered insufficient for this purpose. Thus, a biotin/avidin-enhanced enzyme-linked immunosorbent assay (ELISA) was designed, which detected T.

Bb65, a major immunoreactive protein of Bartonella bacilliformis.

A 65 kDa protein (Bb65) has been identified as one of the major specific antigens of Bartonella bacilliformis, the causative agent of bartonellosis which is a bacterial infectious disease of inhabitants of the Andes. The gene encoding this antigen (7B2) was isolated from an expression library made directly from randomly generated fragments of B. bacilliformis genomic DNA using Bartonella antibodies raised in rabbits and sera of bartonellosis patients.

An epidemic of Oroya fever in the Peruvian Andes.

Between February and October 1987, a febrile illness killed 14 persons and seriously affected at least 14 others in Shumpillan, a remote Peruvian mountain village of 353 people. The illness was characterized by fever, headache, chills, and pallor. The fatality rate of untreated cases was 88%.

Isolation and partial characterization of species-specific and cross-reactive antigens of Echinococcus granulosus cyst fluid.

Two parasite antigens have been isolated from Echinococcus granulosus hydatid cyst fluid using hydrophobic interaction chromatography, anion exchange chromatography and gel filtration chromatography. Initial characterization of the antigens indicates that both are glycoproteins, of approximately 20 and 48 kDa (Eg20 and Eg48). When the two antigens were tested with a battery of antisera from patients with heterologous parasitic infections, only Eg20 was found to be specific for E.

Genomic DNA differences between pathogenic and nonpathogenic Entamoeba histolytica.

cDNA libraries were constructed from pathogenic (HM-1:IMSS) and nonpathogenic (SAW 1734) isolates of Entamoeba histolytica. A cDNA clone (cEH-P1) specific for pathogenic amoebae was identified by screening with a pool of sera from patients with invasive amoebiasis that had been absorbed with nonpathogenic amoebae. This clone was used for the identification of a homologous clone (cEH-NP1) in the cDNA from nonpathogenic amoebae.

Common surface epitope of Bartonella bacilliformis and Chlamydia psittaci.

A serosurvey revealed intense cross-reactivity between Bartonella bacilliformis and Chlamydia psittaci. One of the cross-reacting Bartonella antigens was identified as lipopolysaccharide which reacted with Bartonella as well as with Chlamydia serum antibodies. A monoclonal Bartonella antibody bound to Bartonella lipopolysaccharide as well as to the surfaces of Bartonella bacilliformis and Chlamydia psittaci.

Analysis and preparation of Bartonella bacilliformis antigens.

Twenty-four antigens of Bartonella bacilliformis, a bacterium which causes bartonellosis in residents of high altitude valleys of the Andes, were identified by immunoblot and immunoprecipitation using rabbit anti-Bartonella sera as well as sera of patients. The antigens were designated according to their relative molecular mass which ranged from 16 to 160 kDa. Twelve antigens were detected by antibodies in sera of bartonellosis patients using immunoblot, of which six antigens were detected by immunoprecipitation.

Antiphagocytic activity of streptococcal M protein: selective binding of complement control protein factor H.

Isolated complement components were used to study the regulation of the alternative complement pathway C3 convertase (EC 3.4.21.

Vitamin K-dependent carboxylase. Control of enzyme activity by the "propeptide" region of factor X.

A liver microsomal enzyme catalyzes the vitamin K-dependent posttranslational carboxylation of specific glutamyl residues of a limited number of plasma proteins to gamma-carboxyglutamyl residues. The intracellular precursor forms of these proteins are known to contain a homologous basic amino acid-rich propeptide region between the signal peptide region and the amino terminus of the mature protein. This region of the precursor protein has been implicated as a possible recognition site for the carboxylase enzyme.

Specific and nonspecific immunodiagnostic properties of recombinant and synthetic Plasmodium falciparum antigens.

Six Plasmodium falciparum/beta-galactosidase fusion proteins produced by a genomic DNA expression library, and two synthetic Plasmodium falciparum antigens were applied to ELISA and tested for their immunodiagnostic properties. Results were compared to reference methods, i.e.

Detection of homologous and heterologous malaria antibodies by application of Plasmodium falciparum merozoite antigen to an ELISA.

Sera of patients with anti-plasmodial antibodies determined by indirect fluorescence antibody test (IFAT) were used to evaluate an enzyme immunoassay (IgG ELISA) for determining antibodies to Plasmodium falciparum merozoite antigen. The two tests correlated well. Antibodies to species other than P.

Antibodies to Bartonella bacilliformis as determined by fluorescence antibody test, indirect haemagglutination and ELISA.

Two strains of Bartonella bacilliformis were cultured on Columbia agar supplemented with 5% defibrinated human blood. Antigens prepared from these cultures were used for determination of antibodies by fluorescence antibody test (FAT) indirect haemagglutination (IHA) and an enzyme immunoassay (ELISA). One hundred and eighty-seven human sera from B.