RESUMO
The excessive use of attributes may affect the search for patterns and extraction of useful knowledge, because they harm the learning performance of algorithms in both speed and success rate. The use of dimensionality reduction methods is therefore an important alternative; however, these methods do not deal with the reduction of attributes in a specific area. This article presents a method based on framework concepts of domain for reducing attributes in a domain. The input method is a set of databases related to a domain, and the main process is the identification of common and variable attributes, plus the reduction of attributes in the original database. The proposed method was applied in the gene expression domain, using databases. The method can be used to analyze the most relevant attributes in a specific domain, granting greater confidence for models created for the application of a data mining task, thus, a previously known method in data mining. Attribute selection was also applied in the three databases for the comparison of the results. Analyses of the results using the criterion of cross-validation revealed that the employment of the methods resulted in the improvement of success rates compared to the databases containing the full range of attributes.
Assuntos
Algoritmos , Mineração de Dados , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Humanos , Análise de Sequência com Séries de Oligonucleotídeos/métodosRESUMO
Cutaneous leishmaniases are anthropozoonoses that involve many species of Leishmania and a wide variety of wild mammalian hosts, thus presenting high importance to public health. This study reports the second case of feline leishmaniasis in Mato Grosso do Sul state, in which Leishmania (Leishmania) amazonensis was found in a domestic cat from Ribas do Rio Pardo. Clinical signs were similar to those observed in other diseases commonly diagnosed in cats, such as cryptococcosis and sporotrichosis. Cutaneous leishmaniasis should, therefore, be added to differential diagnoses by feline veterinary practitioners, and also adequate investigations should be carried out to verify the relevance of domestic cats as L. amazonensis reservoirs.
Assuntos
Animais , Gatos , Leishmaniose Cutânea/diagnósticoRESUMO
Although American cutaneous leishmaniasis (ACL) is one of the most important endemic diseases in the Brazilian state of Rondônia, there is very little information on the species of parasite involved. The objective of the present study was to identify the Leishmania species causing ACL in the Monte Negro municipality of the state. Over a 6-year period (1997-2002), the skin lesions of 233 patients were examined while the patients were attending an outpatients' clinic at the University of São Paulo's Advanced Research Unit in Monte Negro. ACL was diagnosed in 137 (58.8%) of the patients and leishmanial parasites were successfully isolated from 14 of the ACL cases. Using a panel of 24 monoclonal antibodies, 12 of the 14 isolates were identified, as L. (Viannia) braziliensis (seven), L. (V.) lainsoni (one), a L. (V.) lainsoni-like species (two), a L. (V.) guyanensis-like species (one), or a L. (Viannia) species that was different from all named species (one). These are the first records of human infection with L. (V.) braziliensis and L. (V.) lainsoni in Rondônia.
Assuntos
Anticorpos Monoclonais , Leishmania/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Animais , Brasil/epidemiologia , Feminino , Humanos , Leishmania/classificação , Leishmaniose Cutânea/epidemiologia , MasculinoRESUMO
A leishmanial parasite isolated in 1977 from a specimen of the sandfly Lutzomyia tuberculata from Pará State, Amazonian Brazil, has been characterized following its comparison with other species of Leishmania from the same region, using isoenzyme profiles, monoclonal antibodies and characterization of the miniexon gene repeat, using the polymerase chain reaction technique (PCR). It is described here under the name of Leishmania (Viannia) utingensis n. sp.
Assuntos
Éxons/genética , Insetos Vetores/parasitologia , Isoenzimas/análise , Leishmania/classificação , Psychodidae/parasitologia , Animais , Anticorpos Monoclonais/imunologia , Brasil , Cricetinae , Leishmania/enzimologia , Leishmania/genética , Leishmania/isolamento & purificação , Filogenia , Reação em Cadeia da Polimerase/veterinária , Pele/parasitologiaRESUMO
The population structure of strains of Leishmania (Viannia) braziliensis sensu lato from Pará State and Paraná State in Brazil, of L. (V.) shawi and L. (Leishmania) amazonensis from Pará State, and the relationships of type strains of the subgenera L. (Viannia) and L. (Leishmania) were examined by the random-amplified polymorphic deoxyribonucleic acid (RAPD) technique. Four different primers (M13-40, QG1, L15996 and delta gt11R) were used. The bands were analysed using the neighbor-joining (NJ) and unweighted pair-group method with arithmetic averages (UPGMA) algorithms of the MEGA package. The topology of the NJ and UPGMA trees was very similar but they were not always identical. Both trees differentiated the standard strains of the different species. Strains from the same location were grouped together only in the UPGMA phenogram of the M13-40 primer. L. (V.) braziliensis isolates from Paraná State were genetically closer to those from Paragominas, Pará State than to those from the Amazonian regions of Carajás in Pará State and Peru. The relationship was not dependent on geographical distance. It is postulated that the groups arose from different origins, in which the Amazonian stocks were related to Psychodopygus sand flies while the Paraná strains originated from a gene pool transmitted by Lutzomyia sand flies such as Lutzomyia (Nyssomyia) whitmani. Transmission by Ps. complexus in Paragominas is considered to be a secondary adaptation from the Lutzomyia leishmanial gene pool. Although the vectors of L. (V.) braziliensis are poorly known in the Amazon region, there is strong evidence that the major vectors are all Psychodopygus spp. There was a high degree of genetic variability amongst the L. (V.) shawi strains and there was no clear grouping according to the strains' origins. The genetic variability amongst L. (L.) amazonensis strains from the same locations was much lower but they formed 2 groups which coincided with their origin. Our results support the clonal population structure of Leishmania isolates and suggest that their distribution is related to the origin of the gene pool as well as to present vector and reservoir movements.
Assuntos
Variação Genética/genética , Leishmania/genética , Animais , Brasil , DNA de Protozoário/genética , Insetos Vetores/parasitologia , Leishmania/classificação , Leishmania braziliensis/classificação , Leishmania braziliensis/genética , Filogenia , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodosRESUMO
The frequency of Leishmania ( Viannia) braziliensis infection was assessed in 79 of the 138 patients with cutaneous leishmaniasis who attended a reference outpatient unit in Manaus, Amazonas state, between the August and December of 1997. The disease was characterized by one or more cutaneous ulcers, the skin lesions being frequently associated with satellite lymph-node enlargement. All parasite isolates were identified using monoclonal antibodies and enzyme electrophoresis. Only two (2.8%) of the 71 patients from whom parasites were successfully isolated were found to be infected with L. ( V.) braziliensis, the other 69 isolates being identified, from their isoenzyme profiles, as L. ( V.) guyanensis. In the Manaus region, therefore, almost all human cutaneous leishmaniasis is the result of infection with L. (V.) guyanensis, and L. ( V.) braziliensis is a relatively rare cause of the disease.
Assuntos
Leishmania braziliensis/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Adolescente , Adulto , Animais , Brasil/epidemiologia , Feminino , Humanos , Leishmania braziliensis/classificação , Leishmania guyanensis/classificação , Leishmania guyanensis/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , MasculinoRESUMO
Eight cases of cutaneous leishmaniasis are recorded among soldiers of the Brazilian Forest Infantry stationed in Belém, State of Pará, north of Brazil. The infections, all acquired during manoeuvres in nearby degraded primary forest, are attributed to a new member of the subgenus Viannia, Leishmania (V.) lindenbergi n. sp. A further infection by this parasite was encountered in a woman, who lived very close to the same piece of forest. The new parasite has been characterised and differentiated from other known species of the subgenus Viannia following the combined use of enzyme electrophoresis and monoclonal antibodies techniques. The eco-epidemiology of L. (V.) lindenbergi is discussed: by far the most abundant anthropophilic sandfly in the type locality was identified as Lutzomyia (Nyssomyia) antunesi (Coutinho), and this remains high on the list of possible vectors.
Assuntos
Surtos de Doenças , Leishmania/isolamento & purificação , Leishmaniose Cutânea/epidemiologia , Militares , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Antiprotozoários/uso terapêutico , Brasil/epidemiologia , Feminino , Humanos , Insetos Vetores/parasitologia , Isoenzimas/análise , Leishmania/classificação , Leishmania/crescimento & desenvolvimento , Leishmania/imunologia , Leishmania/ultraestrutura , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/parasitologia , Masculino , Mefloquina/uso terapêutico , Meglumina/uso terapêutico , Antimoniato de Meglumina , Compostos Organometálicos/uso terapêutico , Proteínas de Protozoários/análise , Psychodidae/parasitologia , ÁrvoresRESUMO
In Colombia it has been suggested that the rodent Proechimys canicollis may be a reservoir-host of Leishmania (L.) chagasi, the cause of American visceral leishmaniasis, based on polymerase chain reaction/hybridization tests. We have detected no infection in laboratory-bred specimens of another species, P. guyannensis, after their inoculation with promastigotes or amastigotes of this parasite from Amazonian Brazil.
Assuntos
Animais Selvagens/parasitologia , Reservatórios de Doenças , Leishmaniose Visceral/transmissão , Roedores/parasitologia , Animais , Brasil , Leishmania infantum/isolamento & purificaçãoRESUMO
During previous research on phlebotomine fauna in a settlement of the Brazilian National Agrarian Reform Institute (INCRA) on the Bodoquena Range, Mato Grosso do Sul State, Brazil, dogs were observed with clinical aspects suggestive of visceral leishmaniasis. A serological survey to leishmaniasis in 97 dogs, by indirect immunofluorescence test, showed 23 (23.7%) serum positive dogs. Samples of the parasites were identified as Leishmania (Leishmania) chagasi.
Assuntos
Doenças do Cão/epidemiologia , Leishmaniose Visceral/veterinária , Animais , Brasil , Cães , Leishmaniose Visceral/epidemiologia , Saúde da População RuralRESUMO
During previous research on phlebotomine fauna in a settlement of the Brazilian National Agrarian Reform Institute (INCRA) on the Bodoquena Range, Mato Grosso do Sul State, Brazil, dogs were observed with clinical aspects suggestive of visceral leishmaniasis. A serological survey to leishmaniasis in 97 dogs, by indirect immunofluorescence test, showed 23 (23.7%) serum positive dogs. Samples of the parasites were identified as Leishmania (Leishmania) chagasi.
Durante estudos sobre a fauna flebotomínea em assentamento do Instituto Nacional de Reforma Agrária (INCRA) na Serra da Bodoquena, Estado de Mato Grosso do Sul, Brasil, foram observados cães com manifestações clínicas sugestivas de leishmaniose visceral. Inquérito sorológico para leishmaniose em 97 cães, utilizando reação de imunofluorescência indireta, mostrou 23 (23,7%) soros reagentes. Amostras do parasita foram identificadas como Leishmania (Leishmania) chagasi.