Diagnostic potential of Western blot analysis of sera from dogs with leishmaniasis in endemic areas and significance of the pattern.

Serum samples collected from 237 dogs in Catalonia (northeastern Spain) were screened by Western blot analysis to detect the presence of antibodies specific to different Leishmania infantum polypeptide fractions. Leishmaniasis was confirmed in 72 of these dogs by direct examination and/or culture. Another 165 animals from the Priorat region were studied periodically for 2-8 years between 1987 and 1995, giving a total of 565 determinations. A control group of 93 dogs from nonendemic areas was also studied. Sera from dogs with leishmaniasis recognized antigens with molecular weights ranging from 12 to 85 kD. The most sensitive antigens were those of 70, 65, 46, 30, 28, 14, and 12 kD, which were recognized by 75%, 75%, 78%, 75%, 81%, 79%, and 75%, respectively, of the sera from dogs with positive parasitologic examination results. Antigens of 70 and 65 kD were also recognized by two dogs from nonendemic areas. Antigens of 14 and 12 kD were the first to be recognized by sera of asymptomatic dogs with titers less than the cut-off value of the dot-ELISA that increased during the longitudinal study, and the presence of antibodies specific for these fractions was observed for up to six years before seroconversion observed by dot-ELISA. These antibodies were also the first to disappear in dogs in which the disease was self-limited. The study corroborates the high sensitivity and specificity of Western blots in the diagnosis of canine leishmaniasis when the bands of low molecular weight (less than 46 kD) are considered, and indicates that fractions of 14 and 12 kD are useful in detecting early forms of the disease.

Gynandromorphism in a population of Sergentomyia minuta (Rondani, 1843) in the northeast of Spain.

A study carried out, from July 1990 until April 1991, in a small village situated in the northeast of Spain (Pradell de la Teixeta) has allowed the discovery of three sandflies species: Phlebotomus ariasi, P. perniciosus and Sergentomyia minuta. P. ariasi was present from the initial data of capture to the end of October, disappearing the two others at the first half of November. The population of S. minuta furnished gynandromorphic individuals (1.6%) being the female-like specimens most commonly found (37/45, 82.2%). The different degrees of development of the genital region are discussed.

[Immunochemical characterization of rabies virus: determination of precipitable antigens]. / Caracterización inmunoquímica de virus rábico: determinación de antigenos precipitables.

Immunodiffusion and immuno-electrophoresis techniques were used to detect rabies precipitable antigens. The passive haemagglutination test with group "O" human red cells treated with tannic acid, was used as control test. The study was done with brain suspensions of rabies virus infected mice (CVS strain). Mouse and horse rabies antisera were used. The analysis of the results of both immunochemical assays showed the presence of two specific antigenic fractions of rabies virus. The same two fractions were detected when the antigens were heated. Experiments with brain extracts centrifuged at high speed, suggested that the antigenic fractions are of the "soluble" type.

Caracterización inmunoquímica de virus rábico: determinación de antigenos precipitables / [Immunochemical characterization of rabies virus: determination of precipitable antigens]

Immunodiffusion and immuno-electrophoresis techniques were used to detect rabies precipitable antigens. The passive haemagglutination test with group [quot ]O[quot ] human red cells treated with tannic acid, was used as control test. The study was done with brain suspensions of rabies virus infected mice (CVS strain). Mouse and horse rabies antisera were used. The analysis of the results of both immunochemical assays showed the presence of two specific antigenic fractions of rabies virus. The same two fractions were detected when the antigens were heated. Experiments with brain extracts centrifuged at high speed, suggested that the antigenic fractions are of the [quot ]soluble[quot ] type.

Caracterización inmunoquímica de virus rábico: determinación de antigenos precipitables. / [Immunochemical characterization of rabies virus: determination of precipitable antigens]

Immunodiffusion and immuno-electrophoresis techniques were used to detect rabies precipitable antigens. The passive haemagglutination test with group [quot ]O[quot ] human red cells treated with tannic acid, was used as control test. The study was done with brain suspensions of rabies virus infected mice (CVS strain). Mouse and horse rabies antisera were used. The analysis of the results of both immunochemical assays showed the presence of two specific antigenic fractions of rabies virus. The same two fractions were detected when the antigens were heated. Experiments with brain extracts centrifuged at high speed, suggested that the antigenic fractions are of the [quot ]soluble[quot ] type.

Lipid Composition of the Hemagglutinating Active Fraction Obtained from Chick Embryos Infected with Chlamydia psittaci 6BC.

The lipid composition of the concentrated hemagglutininating active fraction (HF) of allantoic fluid from infected eggs, but free from Chlamydia psittaci 6BC, was compared to concentrated normal allantoic fluid (NAF). Phosphatidyl-choline (PC) and phosphatidylethanolamine were the major lipid classes of the total phospholipid fraction. Some quantitative differences were found in the amount of PC and phosphatidylserine present in HF and NAF. Lysophosphatidylcholine was present in HF but absent in NAF. Triglycerides and sterols were the major lipid classes found in neutral lipids of HF and NAF. Quantitative data showed distinct differences in the amount of different neutral lipid classes present between HF and NAF. The fatty acids of various classes of lipids were examined, and differences were noted in a number of phospholipids, sterol esters, and the free fatty acids. Branched-chain saturated fatty acids were found in many lipid classes of the HF, particularly in the phosphatidylethanolamine fraction, but were absent in the NAF.