Intraflagellar transport complex in Leishmania spp. In silico genome-wide screening and annotation of gene function.

Flagella are constructed and maintained through the highly conserved process of intraflagellar transport (IFT), which is a rapid movement of particles along the axonemal microtubules of cilia/flagella. Particles that are transported by IFT are composed of several protein subunits comprising two complexes (A and B), which are conserved among green algae, nematodes, and vertebrates. To determine whether or not homologues to members of the IFT complex proteins are conserved in Leishmania spp, we scanned genomes, transcriptomes and proteomes of Leishmania species in a search for putative IFT factors, which were then identified in silico, compared, cataloged, and characterized. Since a large proportion of newly identified genes in L. major remain unclassified, with many of these being potentially Leishmania- (or kinetoplastid-) specific, there is a need for detailed analyses of homologs/orthologs that could help us understand the functional assignment of these gene products. We used a combination of integrated bioinformatics tools in a pathogenomics approach to contribute to the annotation of Leishmania genomes, particularly regarding flagellar genes and their roles in pathogenesis. This resulted in the formal in silico identification of eight of these homologs in Leishmania (IFT subunits, 20, 27, 46, 52, 57, 88, 140, and 172), along with others (IFTs 71, 74/72, and 81), as well as sequence comparisons and structural predictions. IFT, an important flagellar pathway in Leishmania, begins to be revealed through screening of trypanosomatid genomes; this information could also be used to better understand fundamental processes in Leishmania, such as motility and pathogenesis.

Intraflagellar transport complex in Leishmania spp. In silico genome-wide screening and annotation of gene function

Flagella are constructed and maintained through the highly conserved process of intraflagellar transport (IFT), which is a rapid movement of particles along the axonemal microtubules of cilia/flagella. Particles that are transported by IFT are composed of several protein subunits comprising two complexes (A and B), which are conserved among green algae, nematodes, and vertebrates. To determine whether or not homologues to members of the IFT complex proteins are conserved in Leishmania spp, we scanned genomes, transcriptomes and proteomes of Leishmania species in a search for putative IFT factors, which were then identified in silico, compared, cataloged, and characterized. Since a large proportion of newly identified genes in L. major remain unclassified, with many of these being potentially Leishmania- (or kinetoplastid-) specific, there is a need for detailed analyses of homologs/orthologs that could help us understand the functional assignment of these gene products. We used a combination of integrated bioinformatics tools in a pathogenomics approach to contribute to the annotation of Leishmania genomes, particularly regarding flagellar genes and their roles in pathogenesis. This resulted in the formal in silico identification of eight of these homologs in Leishmania (IFT subunits, 20, 27, 46, 52, 57, 88, 140, and 172), along with others (IFTs 71, 74/72, and 81), as well as sequence comparisons and structural predictions. IFT, an important flagellar pathway in Leishmania, begins to be revealed through screening of trypanosomatid genomes; this information could also be used to better understand fundamental processes in Leishmania, such as motility and pathogenesis.

Mecanismos de imunossupressäo na infecçäo aguda pelo "Trypanosoma cruzi" / Immunosuppression mechanisms in acute infection to \"Trypanosoma cruzy\"

Os autores apresentam consideraçöes gerais sobre a resposta de imunossupressao associada à moléstia de Chagas, com o objetivo de contribuir para o entendimento deste importante e promissor ramo do conhecimento.

Mieloma múltiplo / Multiple myeloma

O objetivo do presente artigo é revisar os aspectos do mieloma múltiplo, uma neoplasia de plasmócitos, envolvidos na produçäo de imunoglobulina monoclonal. Abordam-se conceitos etiológicos, patológicos, clínicos e terapêuticos, enfatizando-se os mais recentes avanços no conhecimento desta enfermidade

An immunohistochemical study of the endocrine cells in the gastrointestinal mucosa of the Caiman latirostris.

Twelve endocrine cell types immunoreactive for either 5-hydroxytryptamine (5-HT), somatostatin, gastrin, motilin, neurotensin, bovine pancreatic polypeptide (BPP), avian pancreatic polypeptide (APP), pancreatic glucagon, enteroglucagon, glicentin, secretin or cholecystokinin (CCK) were found in gastrointestinal mucosa of Caiman latirostris. Moderate numbers of enteroglucagon-immunoreactive cells, a few 5-HT-, somatostatin- and motilin-immunoreactive cells and rare pancreatic glucagon-immunoreactive cells were found in the fundic stomach. Numerous gastrin-immunoreactive cells and moderate numbers of somatostatin- and motilin-immunoreactive cells were seen in the pyloric stomach. Moderate numbers of 5-HT-, gastrin-, motilin- and enteroglucagon-immunoreactive cells, a few somatostatin-, neurotensin- and BPP-immunoreactive cells, and rare APP-, pancreatic glucagon-, glicentin-, secretin- and CCK-immunoreactive cells were observed in the proximal intestine. Moderate numbers of 5-HT-immunoreactive cells, small to moderate numbers of neurotensin- and enteroglucagon-immunoreactive cells and occasional somatostatin-, motilin- and BPP-immunoreactive cells were seen in the distal intestine. Moderate numbers of neurotensin-immunoreactive cells and a few 5-HT-immunoreactive cells were found also in the cloaca. Cells immunoreactive for gastrin releasing polypeptide, bombesin and gastric inhibitory peptide were not observed in the caiman gastrointestinal epithelium. The differences in endocrine cell types between the caiman and alligator are discussed in terms of their topographic distribution.

Comparative histometric study in the aortic arch of birds.

A histometric method was here adopted to study the concentration of elastic and collagenous fibers, muscle cells and cellular population of the mesarteria of the middle portion of the aortic arch of several species of birds were studied. The statistical analysis consist of the F test followed by Snedecor 's contrast test. The results obtained show that the concentration decrease on the sequential order of: fibers elastic, muscle cells and collagenous fibers in the goose, duck, black-culture and turkey, while in the peking duck the collagenous fibers were in more amount the muscular tissue, but not exceed the elastic fibers. From the variations pointed out here for the differents elements studied, only those of the muscular tissue have demonstrated a relative statistical signification.

Immunocytochemical study of gastro-entero-pancreatic (GEP) endocrine cells in the vampire bat (Desmodos rotundus).

The distribution and frequency of gastro-entero-pancreatic (GEP) endocrine cells were studied in vampire bats by immunocytochemistry. Moderate numbers of somatostatin- and a few 5-hydroxytryptamine (5-HT)- and glucagon-immunoreactive cells were seen in the fundic cecum of the stomach. Numerous gastrin- and moderate numbers of somatostatin- and 5-HT-immunoreactive cells were found in the pyloric region. Moderate numbers of 5-HT-, somatostatin-, and gastrin-immunoreactive cells also were found in BRUNNER's glands. In addition to the above-mentioned 4 immunoreactive cell types, cells immunoreactive for glicentin, secretin, cholecystokinin (CCK), gastric inhibitory peptide (GIP), and neurotensin were found in the intestine. Numerous insulin-, moderate numbers of somatostatin- and glucagon-, and a few 5-HT-immunoreactive cells were detected in the pancreatic islets with lesser numbers scattered within the exocrine pancreas. Motilin- and pancreatic polypeptide-immunoreactive cells were not observed in this study.

Histochemical study of mucopolysaccharides in epidermal mucous cells and subjacent granular cells of Glossoscolex uruguayensis L. (Righi, 1978).

Histochemical study of mucopolysaccharides of both mucous secreting and subjacent granular cells of the epidermis of Glossoscolex uruguayensis L (Righi, 1978), has been done. Histochemical tests revealed two major types of mucous cells: large ortochromatic mucous cells and metachromatic mucous cells. The first ones possess alpha-amylase resistant, PAS-positive material, together with little mucic acid, and the latter present a very low rate of neutral mucopolysaccharides and to a variable degree, both carboxylate and sulphate mucopolysaccharides. A third cell type was also detected, presenting a frothy acid like material. Subjacent epidermal granular cells display alpha-amylase resistant, PAS-positive granules, with no acid mucus.

Histochemical study of polysaccharides in the aortic arch of some birds.

The histochemical study of polysaccharides in the aortic arch of the black vulture, turkey, peking duck, goose and duck, showed that a sialo-mucopolysaccharidic complex is present in the vessel wall and consists of: sialic acid, neutral mucopolysaccharides, hyaluronic acid and Chondrotin sulfate. The concentration of mucopolysaccharides, mainly of the acidic ones, decreases from the inner portions of the media towards the adventicia.

Naturally occuring histoplasmosis in guinea pigs.

Histoplasmosis naturally occurring in laboratory guinea pigs is described in its clinical, necropsy, histological and mycological aspects.The animals if adult show a chronic disease with progressive emaciation and lameness of the hind legs. The young below three months of age died in 2 to 4 weeks presenting ruffled fur, great dorsal curvature and sometimes closed eyelids and catarrhal conjunctivitis. At necropsy the principal lesions were ulcerative gastritis, hemorrhagic and catarrhal enteritis, enlarged spleen and mesenteric lymph nodes. Sometimes the liver, lungs, mediastinal lymph nodes and other organs showed lesions. Histological and mycological demonstration of the fungus completed the diagnosis and the surviving animals were burned and sanitation measures instituted. Histological evidence of histoplasmosis in a cow's lung from the area from which the grass was obtained for the feeding of the guinea pigs suggests an epidemiological link. Efforts will be made to isolate and demonstrate H. capsulatum in wild animals on the same area.