Subject(s)
Ixodidae/microbiology , Rickettsia felis/classification , Rickettsia felis/isolation & purification , Animals , Bacterial Outer Membrane Proteins/genetics , Cell Line , Coculture Techniques , Croatia , Culicidae , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Molecular Sequence Data , Polymerase Chain Reaction , Sequence Analysis, DNA , Sequence HomologyABSTRACT
The authors describe their work in the Americas in Rickettsia felis cases in humans and the presence of Rickettsia felis in vectors.
Subject(s)
Rickettsia Infections/epidemiology , Rickettsia felis , Animals , Humans , Insect Vectors , North America/epidemiology , Rickettsia Infections/diagnosis , South America/epidemiologyABSTRACT
In search for the vector of the recently recognized spotted fever rickettsiosis of the Yucatán, ticks, fleas, and lice were collected from vegetation and dogs in localities where seropositive persons had been found. The arthropods were examined by polymerase chain reaction (PCR) using primers for the genus-specific 17-kDa protein gene followed by restriction fragment length polymorphism (RFLP) and DNA sequencing. Eleven (20%) of 54 pools of Ctenocephalides felis fleas contained DNA of Rickettsia felis. None of 219 Amblyomma cajennense, 474 Rhiphicephalus sanguineus, 258 Boophilus sp. ticks, and 33 Poliplax species lice contained DNA of Rickettsia. The identity of the rickettsial DNA was confirmed as R. felis by PCR/RFLP for the citrate synthase and outer membrane protein A genes and by DNA sequencing. The results indicate that the host of R. felis in Yucatán is C. felis and suggest that the spotted fever rickettsiosis that has infected >5% of the population of the Yucatán and can present as a dengue-like illness is likely to be caused by R. felis.
Subject(s)
Insect Vectors/microbiology , Rickettsia Infections/microbiology , Rickettsia felis/isolation & purification , Siphonaptera/microbiology , Animals , DNA, Bacterial/isolation & purification , Insect Vectors/classification , Mexico/epidemiology , Rickettsia Infections/epidemiology , Rickettsia felis/genetics , Siphonaptera/classificationABSTRACT
Knowledge regarding kinetoplast DNA organization in all members of the Trypanosomatid family is incomplete. Recently, the presence of kinetoplast-associated proteins in condensing kDNA networks in Crithidia fasciculata has been described and a role for these proteins in the maintenance of these complex structures was suggested. To investigate the presence of protein components in Trypanosoma cruzi kinetoplast, we previously described seven epimastigote kinetoplast-associated proteins. We report here the existence of kinetoplast binding proteins in amastigote and trypomastigote stages of T. cruzi, which could bind both mini and maxicircles components with a stage specific elements for every infective form of the parasite. We propose three major classes of kinetoplast-associated proteins related to the basic processes of this intricate disc structure and suggest a possible function of these binding proteins in the T. cruzi mitochondrial DNA organization.
Subject(s)
Bacterial Proteins , DNA, Kinetoplast/chemistry , DNA-Binding Proteins/chemistry , Protozoan Proteins/chemistry , Trypanosoma cruzi/chemistry , Animals , Blotting, Western , DNA Probes/chemistry , DNA, Kinetoplast/isolation & purification , Deoxyribonucleases, Type II Site-Specific/chemistry , Electrophoresis, Polyacrylamide Gel , Humans , Trypanosoma cruzi/geneticsABSTRACT
The purpose of this study was to determine the frequency of cardiopathy due to Chagas' disease in 36 patients of the cardiology department at the Regional General Hospital O'Horan in Merida, Yucatan. All patients included in the study had cardiac involvement compatible with acute or chronic stages of Chagas' disease. Medical records prepared for each one of the patients included a Chagas' disease targeted clinical history, chest X-ray, electrocardiogram, blood culture and serology using indirect immunofluorescence test. Out of the 36 patients studied, 7 were diagnosed as having Chagas' disease cardiopathy. Grade II cardiomegaly was established in 2 patients while the remaining 5 had grade III cardiomegaly. Conduction abnormalities were established in 6 patients while 2 of these had evidence of necrosis and/or ischemia. Chagas' disease cardiopathy, as our results suggest, is not a rare event in the cardiology ward at the O'Horan Hospital.
Subject(s)
Chagas Cardiomyopathy/epidemiology , Chagas Cardiomyopathy/diagnosis , Chronic Disease , Female , Hospitals, General , Humans , Mexico , Middle AgedABSTRACT
Intracellular forms of trypanosoma cruzi, amastigote, could remain in the inner space of mammalian cells for long periods of time and be in contact with various cellular metabolism products. Some of these metabolites could act as signals that trigger parasite differentiation process to trypomastigote form. The present results suggest that increase of intracellular cAMP by adrenergic ligands or cholera toxin in parasite infected cells is able to induce such differentiation process.
Subject(s)
Adrenergic beta-Agonists/pharmacology , Cholera Toxin/pharmacology , Isoproterenol/pharmacology , Trypanosoma cruzi/drug effects , Animals , Cyclic AMP/metabolism , Ligands , Mice , Mice, Inbred Strains , Trypanosoma cruzi/growth & development , Trypanosoma cruzi/metabolismABSTRACT
Seventeen Mexican Trypanosoma cruzi stocks and five South American reference strains were analyzed by Hind III restriction fragment length polymorphisms associated with ribosomal RNA gene spacers and by HinfI digestion patterns of total DNA. Our findings demonstrate the occurrence of genetic heterogeneity within these stocks. Hierarchic and non-hierarchic clustering of these molecular characters allowed the formation of groups that correlate with the geographic origin of the stocks. The HinfI digestion pattern permitted the identification of DNA fragments from the kinetoplast maxi-circles, and therefore represents a simple and convenient method for conducting epidemiologic surveys in laboratories in developing countries.