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1.
Nanomaterials (Basel) ; 13(17)2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37687002

RESUMO

This work reports on the photocatalytic activity of tin oxide (SnO2)-doped magnesium (Mg) and fluorine (F) nanoparticles for methyl orange and safranin dye degradation under sunlight irradiation. Nanocatalysis-induced dye degradation was examined using UV-visible spectroscopy and a pseudo-first-order kinetics model. The results indicate that the prepared nanoparticles exhibit superior photocatalytic activity, and the degradation of methyl orange (MO) dye is approximately 82%. In contrast, the degradation of safranin dye is 96% in the same time interval of 105 min. The calculated crystallite size of the SnO2-Mg-F nanocomposite is 29.5 nm, which respects the particle size found in the DLS analysis with a tetragonal structure and spherical morphology affirmed. The optical characteristics were assessed, and their respective bandgap energies were determined to be 3.6 eV. The influence of F in Mg and SnO2 is recognized with the XRD and FT-IR spectra of the prepared particles.

2.
Nanomaterials (Basel) ; 13(9)2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37177068

RESUMO

New NiSn(OH)6 hexahydroxide nanoparticles were synthesised through a co-precipitation method using various concentrations of Ni2+ and Sn4+ ions (e.g., 1:0, 0:1, 1:2, 1:1, and 2:1; namely, N, S, NS-3, NS-2, and NS-1) with an ammonia solution. The perovskite NiSn(OH)6 was confirmed from powder X-ray diffraction and molecule interactions due to different binding environments of Ni, Sn, O, and water molecules observed from an FT-IR analysis. An electronic transition was detected from tin (Sn 3d) and nickel (Ni 2p) to oxygen (O 2p) from UV-Vis/IR spectroscopy. Photo luminescence spectroscopy (PL) identified that the emission observed at 400-800 nm in the visible region was caused by oxygen vacancies due to various oxidation states of Ni and Sn metals. A spherical nanoparticle morphology was observed from FE-SEM; this was due to the combination of Ni2+ and Sn4+ increasing the size and porosity of the nanoparticle. The elemental (Ni and Sn) distribution and binding energy of the nanoparticle were confirmed by EDAX and XPS analyses. Among the prepared various nanoparticles, NS-2 showed a maximum specific capacitance of 607 Fg-1 at 1 Ag-1 and 56% capacitance retention (338 Fg-1 and 5 Ag-1), even when increasing the current density five times, and excellent cycle stability due to combining Ni2+ with Sn4+, which improved the ionic and electrical conductivity. EIS provided evidence for NS-2's low charge transfer resistance compared with other prepared samples. Moreover, the NS-2//AC (activated carbon) asymmetric supercapacitor exhibited the highest energy density and high-power density along with excellent cycle stability, making it the ideal material for real-time applications.

3.
Parasitology ; 136(6): 589-94, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19402949

RESUMO

Cats are essential in the epidemiology of Toxoplasma gondii because they are the only hosts that can excrete the environmentally resistant oocysts in nature. Samples of serum, feces, and tissues from feral cats from St Kitts, West Indies were examined for T. gondii infection. Antibodies to T. gondii were assayed by the modified agglutination test, and found in 71 of 96 (73.9%) of cats with titres of 1:10 in six, 1: 20 in six,1:40 in seven,1: 80 in three, 1: 160 in 10, 1:320 in 13, 1:640 in nine, and 1:1,280 or higher in 17. Tissues of 10 cats were bio-assayed in mice. Toxoplasma gondii was isolated from tissues of 7 cats; from hearts of 6, from tongue of 5, and brains of 3 cats. All 7 isolates were avirulent for mice. Toxoplasma gondii oocysts were not found in the feces of 51 cats. Genotyping of these 7 T. gondii isolates by 10 multi-locus PCR-RFLP markers, including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and an apicoplast marker, Apico, revealed 4 genotypes, including clonal Type II, Type III and 2 unique genotypes. Five of the 7 cats had infection with 2 genotypes, indicating high frequency of mixed infection in the cat population on the St Kitts island.


Assuntos
Doenças do Gato/parasitologia , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Animais , Anticorpos Antiprotozoários/sangue , Doenças do Gato/epidemiologia , Gatos , Fezes/parasitologia , Feminino , Genes de Protozoários/genética , Genótipo , Masculino , Camundongos , Prevalência , Toxoplasmose Animal/epidemiologia , Índias Ocidentais/epidemiologia
4.
J Parasitol ; 95(1): 95-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19245283

RESUMO

Pigs are considered to be the most important meat source of Toxoplasma gondii for humans in the United States. In the present study, 168 T. gondii isolates (designated TgPgUs15-182) from various sources were genotyped using 10 polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). Genotyping data from an additional 14 isolates collected from T. gondii-infected pigs in Maryland were included for analysis. Nine genotypes (1-9) were recognized from the 182 T. gondii isolates. Most (56%, 102) isolates were clonal Type II (genotypes 1 and 2) and 27% (49) were clonal Type III (genotype 3) strains. Genotype 4 had Type II alleles, with the exception of Type I alleles at loci Apico and L358. Eight isolates (genotype 5) from Iowa had a combination of alleles I, II, and III at different loci. The remaining 6 isolates were divided into genotypes 6-9 and had a combination of different alleles. Eight of the 9 genotypes were previously reported in different animal species and geographic regions. In conclusion, along with the predominance of clonal Type II and III strains, a few diverse, previously unrecognized T. gondii lineages were found circulating in domestic pigs used for human consumption.


Assuntos
Doenças dos Suínos/parasitologia , Toxoplasma/classificação , Toxoplasmose Animal/parasitologia , Matadouros , Testes de Aglutinação/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Bioensaio/métodos , Bioensaio/veterinária , Gatos , DNA de Protozoário/química , Feminino , Marcadores Genéticos , Genótipo , Maryland , Carne/parasitologia , Camundongos , Suínos , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasma/patogenicidade , Estados Unidos , Virulência
5.
J Parasitol ; 95(2): 467-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18847295

RESUMO

Pectoral muscles from a captive keel-billed toucan (Ramphastos sulfuratus) from Costa Rica were fed to a Toxoplasma gondii-free cat, and the cat shed oocysts. Laboratory mice fed these oocysts developed antibodies to T. gondii in their sera and T. gondii tissue cysts in their brains. The DNA extracted from the brains of infected mice was characterized using 10 polymerase chain reaction-restricted fragment length polymorphic markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). The isolate designated TgRsCrl was found to be non-clonal with Type I, II, and III alleles at different loci. This is the first isolation of T. gondii from this host.


Assuntos
Doenças das Aves/parasitologia , Músculos Peitorais/parasitologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Animais , Animais de Zoológico , Bioensaio/veterinária , Aves , Gatos , Costa Rica , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Evolução Fatal , Marcadores Genéticos/genética , Genótipo , Camundongos , Polimorfismo Genético , Toxoplasma/classificação , Toxoplasma/genética
6.
J Parasitol ; 95(1): 82-5, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19245284

RESUMO

Toxoplasma gondii infection in marine mammals is intriguing and indicative of contamination of the ocean environment and coastal waters with oocysts. Toxoplasma gondii infection was detected in captive marine mammals at a sea aquarium in Canada. Antibodies to T. gondii were found in all 7 bottlenose dolphins (Tursiops truncatus) tested. Two of these dolphins, as well as a walrus (Odobenus rosmarus) at the facility, died. Encephalitis and T. gondii tissue cysts were identified in histological sections of the brain of 1 dolphin (dolphin no. 1). Another dolphin (dolphin no. 2) had mild focal encephalitis without visible organisms, but viable T. gondii was isolated by bioassay in mice and cats from its brain and skeletal muscle; this strain was designated TgDoCA1. The PCR-RFLP typing using 11 markers (B1, SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico) identified a Type II strain. The DNA sequencing of B1 and SAG1 alleles amplified from TgDoCA1 and directly from the brains of dolphin no. 1 and the walrus showed archetypal alleles consistent with infection by a Type II strain. No unique polymorphisms were detected. This is apparently the first report of isolation of T. gondii from a marine mammal in Canada.


Assuntos
Golfinho Nariz-de-Garrafa/parasitologia , Toxoplasmose Animal/epidemiologia , Toxoplasmose Cerebral/veterinária , Morsas/parasitologia , Animais , Animais de Zoológico , Anticorpos Antiprotozoários/sangue , Bioensaio/veterinária , Encéfalo/parasitologia , Encéfalo/patologia , Canadá/epidemiologia , Gatos , DNA de Protozoário/análise , DNA de Protozoário/química , Feminino , Imuno-Histoquímica/veterinária , Masculino , Camundongos , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/diagnóstico , Toxoplasmose Animal/parasitologia , Toxoplasmose Cerebral/diagnóstico , Toxoplasmose Cerebral/epidemiologia , Toxoplasmose Cerebral/parasitologia
7.
J Parasitol ; 95(2): 319-22, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18925790

RESUMO

Little is known concerning the epidemiology of Toxoplasma gondii infection in people and animals in rural Mexico. Serum samples and tissues from 150 dogs (Canis familaris), 150 cats (Felis catus), 65 opossums (Didelphis virginianus), 249 rats (Rattus spp.), 127 mice (Mus musculus), and 69 squirrels (Spermophilus variegatus) from the Durango area were evaluated for T. gondii infection. Using a modified agglutination test and a serum dilution of 1:25, antibodies to this parasite were found in 68 (45.3%) of 150 dogs, 14 (9.3%) of 150 cats, 11 (16.6%) of 66 opossums, 2 (0.8%) of 249 rats, 4 (3.1%) of 127 mice, and 0 of 69 squirrels. Tissues (brain and heart) of dogs, cats, opossums, rats, mice, and squirrels were bioassayed in mice for the presence of T. gondii. Viable T. gondii was isolated in tissues from 3 of 28 seropositive dogs and 5 of 8 seropositive cats, but not from the other animals. The DNA obtained from the 3 T. gondii isolates from dogs, 6 isolates from 5 cats, and 4 isolates from free-range chickens from Mexico, previously isolated, were genotyped. The PCR-RFLP typing, which used 11 markers (B 1, SAGI, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico), identified 5 genotypes. One genotype (the 4 chicken isolates) belongs to the clonal Type III lineage, three genotypes were reported in previous reports, and 1 genotype is unique.


Assuntos
Doenças do Gato/parasitologia , Galinhas/parasitologia , Doenças do Cão/parasitologia , Gambás/parasitologia , Doenças dos Roedores/parasitologia , Toxoplasmose Animal/parasitologia , Animais , Anticorpos Antiprotozoários/sangue , Bioensaio/veterinária , Doenças do Gato/epidemiologia , Gatos , Doenças do Cão/epidemiologia , Cães , Feminino , Genótipo , Masculino , México/epidemiologia , Camundongos/parasitologia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/parasitologia , Ratos/parasitologia , Doenças dos Roedores/epidemiologia , Sciuridae/parasitologia , Estudos Soroepidemiológicos , Toxoplasma/classificação , Toxoplasma/imunologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/epidemiologia
8.
Int J Parasitol ; 38(8-9): 1057-63, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18187136

RESUMO

Clinical toxoplasmosis is most severe in congenitally-infected hosts. In humans, transmission of Toxoplasma gondii from the mother to the foetus is considered to be most efficient during the last trimester of pregnancy but clinical congenital toxoplasmosis is more severe if transmission occurs during the first trimester. However, there are no data on the rate of congenital transmission of T. gondii with respect to gestational age in any host during natural infection. In the present study, attempts were made to isolate T. gondii by bioassay in mice inoculated with tissues from foetuses of 88 naturally-exposed white-tailed deer from Iowa and Minnesota. Viable T. gondii was isolated from foetuses of six of 61 deer in early pregnancy (45-85 days of gestation) from Iowa and foetuses of nine of 27 deer from Minnesota in mid-gestation (130-150 days) of a gestational period of 7 months. The 15 T. gondii isolates obtained from foetal deer were PCR-restriction fragment length polymorphism genotyped using polymorphisms at 10 nuclear markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and an apicoplast marker, Apico. Five genotypes were revealed, including the clonal Type II and III lineages, and three non-clonal genotypes. DNA sequencing analysis of representative isolates at loci SAG2, c22-8, L358 and PK1 revealed that the three non-clonal genotypes are closely related to the clonal Type I, II and III lineages. It is very likely that these non-clonal genotypes were derived from genetic crosses among the three clonal Type I, II and III lineages. The most common genotype was Type II, commonly found in humans in North America and Europe, suggesting the possible link of transmission from game animals to humans.


Assuntos
Cervos/parasitologia , Feto/parasitologia , Transmissão Vertical de Doenças Infecciosas/veterinária , Toxoplasma/genética , Toxoplasmose Animal/genética , Toxoplasmose Animal/transmissão , Toxoplasmose Congênita/genética , Animais , Anticorpos Antiprotozoários/isolamento & purificação , Feminino , Genótipo , Idade Gestacional , Humanos , Produtos da Carne/parasitologia , Camundongos , Polimorfismo de Fragmento de Restrição , Gravidez , Toxoplasma/imunologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/embriologia , Toxoplasmose Congênita/embriologia , Toxoplasmose Congênita/parasitologia
9.
Int J Parasitol ; 38(8-9): 999-1006, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18191859

RESUMO

Little information is available on the presence of viable Toxoplasma gondii in tissues of lambs worldwide. The prevalence of T. gondii was determined in 383 lambs (<1 year old) from Maryland, Virginia and West Virginia, USA. Hearts of 383 lambs were obtained from a slaughter house on the day of killing. Blood removed from each heart was tested for antibodies to T. gondii by using the modified agglutination test (MAT). Sera were first screened using 1:25, 1:50, 1: 100 and 1:200 dilutions, and hearts were selected for bioassay for T. gondii. Antibodies (MAT, 1:25 or higher) to T. gondii were found in 104 (27.1%) of 383 lambs. Hearts of 68 seropositive lambs were used for isolation of viable T. gondii by bioassay in cats, mice or both. For bioassays in cats, the entire myocardium or 500g was chopped and fed to cats, one cat per heart and faeces of the recipient cats were examined for shedding of T. gondii oocysts. For bioassays in mice, 50g of the myocardium was digested in an acid pepsin solution and the digest inoculated into mice; the recipient mice were examined for T. gondii infection. In total, 53 isolates of T. gondii were obtained from 68 seropositive lambs. Genotyping of the 53 T. gondii isolates using 10 PCR-restriction fragment length polymorphism markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico) revealed 57 strains with 15 genotypes. Four lambs had infections with two T. gondii genotypes. Twenty-six (45.6%) strains belong to the clonal Type II lineage (these strains can be further divided into two groups based on alleles at locus Apico). Eight (15.7%) strains belong to the Type III lineage. The remaining 22 strains were divided into 11 atypical genotypes. These results indicate high parasite prevalence and high genetic diversity of T. gondii in lambs, which has important implications in public health. We believe this is the first in-depth genetic analysis of T. gondii isolates from sheep in the USA.


Assuntos
Coração/parasitologia , Doenças dos Ovinos/parasitologia , Carneiro Doméstico/parasitologia , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/transmissão , Animais , Bioensaio , Gatos , Genótipo , Humanos , Produtos da Carne/parasitologia , Camundongos , Ovinos , Toxoplasma/crescimento & desenvolvimento , Estados Unidos
10.
Vet Parasitol ; 155(3-4): 314-8, 2008 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-18583059

RESUMO

Until recently, Toxoplasma gondii was considered to be clonal with very little genetic variability. Recent studies indicate that T. gondii isolates from Brazil are genetically and biologically different from T. gondii isolates from USA and Europe. However, little is known of the genetics of T. gondii strains from Africa. In this study, we genotyped 19 T. gondii isolates from chickens from six African countries (Egypt, Kenya, Nigeria, Congo, Mali, and Burkina Fasco) using 10 PCR-RFLP markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). The results revealed four genotypes. Thirteen isolates belong to the Type III lineage, five isolates have Type II alleles at all loci except apico and they belong to the Type II lineage. One isolate from Nigeria had atypical genotype. In general, these isolates were mostly clonal Type III and II strains that predominate in North American and European. DNA sequencing at several loci for representative isolates confirmed the results of PCR-RFLP genotyping. Taken together with recent studies of T. gondii isolates from Africa, it is clear that the three clonal lineages (Types I, II and III) predominate not only in North America and Europe, but also in Africa.


Assuntos
Galinhas/parasitologia , Toxoplasma/genética , Toxoplasma/isolamento & purificação , África , Animais , Europa (Continente) , Genótipo , Dados de Sequência Molecular , América do Norte , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Doenças das Aves Domésticas/parasitologia , Toxoplasma/classificação , Toxoplasmose Animal/parasitologia
11.
Vet Parasitol ; 157(3-4): 299-305, 2008 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-18804329

RESUMO

Until recently, Toxoplasma gondii was considered clonal with very little genetic variability. Recent studies indicate that T. gondii isolates from Brazil are genetically and biologically different from T. gondii isolates from USA and Europe. In the present study, we retyped 151 free range chicken isolates from Brazil including 117 newly isolated samples from 11 geographically areas (Alagoas, Bahia, Ceará, Maranhão, Paraná, Pernambuco, Rio de Janeiro, Rio Grande do Norte, São Paulo, Sergipe, and Rondonia) and 34 previously reported isolates from the very north (Pará) and the very south (Rio Grande do Sul). Ten PCR-RFLP markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico were used to genotype all isolates. Overall analysis of 151 T. gondii isolates revealed 58 genotypes. Half (29/58) of these genotypes had single isolate and the other half of the genotypes were characterized with two or more isolates. Only 1 of 151 isolates was clonal Type I strain and 5 were clonal Type III strains. Two isolates had mixed infections. Clonal Type II strain was absent. One strain was Type II at all loci, except BTUB. The results confirm high genetic diversity of T. gondii isolates from Brazil.


Assuntos
Galinhas/parasitologia , Variação Genética , Doenças das Aves Domésticas/parasitologia , Toxoplasma/genética , Toxoplasmose Animal/parasitologia , Animais , Brasil/epidemiologia , Genótipo , Filogenia , Doenças das Aves Domésticas/epidemiologia , Toxoplasmose Animal/epidemiologia
12.
J Parasitol ; 94(1): 36-41, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18372619

RESUMO

The prevalence of Toxoplasma gondii was investigated on a poorly managed pig farm in Maryland. Serum and tissue samples from 48 of the 100 pigs on the farm were available for T. gondii evaluation. Serological testing was performed using both ELISA and the modified agglutination test (MAT). Antibodies to T. gondii were detected by ELISA in 12 of 48 animals, while antibodies were detected in 34 of 48 pigs by MAT with titers of 1:10 in 1, 1:20 in 4, 1:40 in 7, 1:80 in 3, 1:160 in 8, 1:320 in 3, 1:640 in 4, and 1:1,280 in 4. Hearts of 16 pigs with MAT titers of 1:10 or higher were bioassayed for T. gondii in cats; 11 cats shed T. gondii oocysts. Hearts of 22 pigs were autolyzed and bioassayed only in mice; T. gondii was isolated from 3 of these 22 pigs. Genetic typing of the 14 T. gondii isolates using the SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico loci revealed 4 genotypes; 10 isolates belonged to type II lineage (genotypes 1 and 2), 3 belonged to genotype 3, and 1 belonged to genotype 4. Genotype 1 and 2 have type II alleles at all genetic loci, except the former has type II allele and the latter has a type I allele at locus Apico. Both genotypes 1 and 2 are considered to belong to the clonal type II lineages. Genotype 3 and 4 are nonclonal isolates. Results document high prevalence of T. gondii in pigs on a farm in Maryland.


Assuntos
Doenças Endêmicas/veterinária , Doenças dos Suínos/epidemiologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/epidemiologia , Testes de Aglutinação/veterinária , Alelos , Animais , Anticorpos Antiprotozoários/sangue , Bioensaio , Gatos , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Genótipo , Coração/parasitologia , Masculino , Maryland/epidemiologia , Camundongos , Prevalência , Suínos , Doenças dos Suínos/parasitologia , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Animal/parasitologia
13.
J Parasitol ; 94(1): 42-5, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18372620

RESUMO

Viable Toxoplasma gondii was isolated by bioassay in mice from tissues of 2 feral cats (Felis domesticus), 2 raccoons (Procyon lotor), a skunk (Mephitis mephitis) trapped in remote locations in Manitoba, Canada, and a black bear (Ursus americanus) from Kuujjuaq, northern Quebec, Canada. Genotyping of these T. gondii isolates using polymorphisms at 10 nuclear markers including SAGI, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and an apicoplast marker Apico revealed 4 genotypes. None of the isolates was clonal archetypal Types I, II, and III found in the United States. These results are in contrast with the Type II genotype that is widespread in domestic animals and humans throughout the United States and Europe. This is the first genotyping of T. gondii isolates from this part of North America.


Assuntos
Carnívoros/parasitologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/parasitologia , Animais , Bioensaio , Encéfalo/parasitologia , Canadá/epidemiologia , Doenças do Gato/epidemiologia , Doenças do Gato/parasitologia , Gatos , DNA de Protozoário/química , Fezes/parasitologia , Feminino , Genótipo , Pulmão/parasitologia , Masculino , Mephitidae/parasitologia , Camundongos , Músculo Esquelético/parasitologia , Puma/parasitologia , Guaxinins/parasitologia , Língua/parasitologia , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasmose Animal/epidemiologia , Ursidae/parasitologia
14.
J Parasitol ; 94(1): 68-71, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18372623

RESUMO

The prevalence of Toxoplasma gondii in free-ranging chickens (Gallus domesticus) is a good indicator of the prevalence of the parasite's oocysts in soil because chicken feed from the ground. The prevalence of T. gondii in free-range chickens from Ghana, Indonesia, Italy, Poland, and Vietnam was determined using the modified agglutination test (MAT). Antibodies to T. gondii were found in 41 (64%) of 64 chickens from Ghana, 24 (24.4%) of 98 chickens from Indonesia, 10 (12.5%) of 80 chickens from Italy, 6 (30%) of 20 chickens from Poland, and 81 (24.2%) of 330 chickens from Vietnam. Hearts and brains of chickens were bioassayed for T. gondii. Viable T. gondii was isolated from 2 chickens from Ghana, 1 chicken from Indonesia, 3 chickens from Italy, 2 chickens from Poland, and 1 chicken from Vietnam. Toxoplasma gondii isolates from 9 chickens were genotyped using 10 PCR-RFLP markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico. A total of 7 genotypes was identified; the 3 isolates from chickens from Italy were clonal type II, and the others were nonclonal. This is the first report of genetic characterization of T. gondii isolates from animals from these countries.


Assuntos
Galinhas/parasitologia , Doenças das Aves Domésticas/epidemiologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/epidemiologia , Animais , Anticorpos Antiprotozoários/sangue , Bioensaio/veterinária , Gatos , DNA de Protozoário/química , Feminino , Genótipo , Gana/epidemiologia , Indonésia/epidemiologia , Itália/epidemiologia , Camundongos , Polônia/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Doenças das Aves Domésticas/parasitologia , Estudos Soroepidemiológicos , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Animal/parasitologia , Vietnã/epidemiologia
15.
J Parasitol ; 94(4): 821-3, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18576793

RESUMO

Toxoplasma gondii infection in marine mammals is intriguing and indicative of contamination of the ocean environment and coastal waters with oocysts. In previous serological surveys, >90% of bottlenose dolphins (Tursiops truncatus) from the coasts of Florida, South Carolina, and California had antibodies to T. gondii by the modified agglutination test (MAT). In the present study, attempts were made to isolate T. gondii from dead T. truncatus. During 2005, 2006, and 2007, serum or blood clot, and tissues (brain, heart, skeletal muscle) of 52 T. truncatus stranded on the coasts of South Carolina were tested for T. gondii. Antibodies to T. gondii (MAT 1:25 or higher) were found in 26 (53%) of 49 dolphins; serum was not available from 3 animals. Tissues (heart, muscle, and sometimes brain) of 32 dolphins (26 seropositive, 3 seronegative, and 3 without accompanying sera) were bioassayed for T. gondii in mice, or cats, or both. Tissues of the recipient mice were examined for T. gondii stages. Feces of recipient cats were examined for shedding of T. gondii oocysts, but none excreted oocysts. Toxoplasma gondii was isolated from hearts of the 3 dolphins (2 with MAT titers of 1:200, and 1 without accompanied serum) by bioassay in mice. Genotyping of these 3 T. gondii isolates (designated TgDoUs1-3) with the use of 10 PCR-RFLP markers (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico) revealed 2 genotypes. Two of the 3 isolates have Type II alleles at all loci and belong to the clonal Type II lineage. One isolate has a unique genotype. This is the first report of isolation of viable T. gondii from T. truncatus.


Assuntos
Golfinho Nariz-de-Garrafa/parasitologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/epidemiologia , Testes de Aglutinação/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Bioensaio/veterinária , Gatos , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Feminino , Marcadores Genéticos , Genótipo , Coração/parasitologia , Camundongos , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasma/imunologia , Toxoplasmose Animal/parasitologia
16.
Neural Netw ; 105: 236-248, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29870931

RESUMO

This paper investigates H∞ state estimation problem for a class of semi-Markovian jumping discrete-time neural networks model with event-triggered scheme and quantization. First, a new event-triggered communication scheme is introduced to determine whether or not the current sampled sensor data should be broad-casted and transmitted to the quantizer, which can save the limited communication resource. Second, a novel communication framework is employed by the logarithmic quantizer that quantifies and reduces the data transmission rate in the network, which apparently improves the communication efficiency of networks. Third, a stabilization criterion is derived based on the sufficient condition which guarantees a prescribed H∞ performance level in the estimation error system in terms of the linear matrix inequalities. Finally, numerical simulations are given to illustrate the correctness of the proposed scheme.


Assuntos
Redes Neurais de Computação , Cadeias de Markov , Fatores de Tempo
17.
J Photochem Photobiol B ; 189: 152-164, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30352369

RESUMO

A new class of triazine ligands (E)-2-(2-(6-methyl-5-oxo-2,5-dihydro-1,2,4-triazin-3-yl)hydrazono)propanoic acid hydrate (HL1.H2O) and (Z)-2-(((E)-4-amino-6-methyl-5-oxo-4,5-dihydro-1,2,4-triazin-3(2H)ylidene)hydrazono)propanoic acid (H2L2) has been synthesized by the condensation reaction of pyruvic acid with diaminoguanidine and triaminoguanidine respectively. The corresponding Schiff base cobalt complexes [Co(L1)2].2H2O (1) and [Co(HL2)(L2)].H2O (2) have also been synthesized and characterized by analytical, thermal, spectroscopic and diffraction studies. Strong field ligand results low spin Co(III) centre in 2, which was evidenced by the shorter bond length of Co(III) complex. In H2L2 there is a choice of coordination modes based on distinct sets of donor atoms, both of which are seen in complex 2, involving either an -NH2 group on position 4 of the triazine ring, or via a ring nitrogen of the triazine itself. The deprotonation of one version of L2 allows the formation of the ligand field stabilized low spin Co(III) in 2. In complex 1, each ligand binds to the metal via pyruvate oxygen, azomethine nitrogen and triazine nitrogen forming two five-membered stable chelate rings. In complex 2, the coordination sphere assembled by two types of coordinating atoms from the same ligand with different conformation. Their binding ability and mode of binding with CT-DNA and BSA was studied by UV- absorption, fluorescence and CD spectroscopy. Density Functional Theory (DFT) studies provide further insights into the mode of binding, structure and mechanism. The HOMO and LUMO energy gap values indicate that both the complexes are prone to interact with CT-DNA and BSA. We have also performed molecular docking calculations to understand the mode of binding and the corresponding results confirm our experimental findings.


Assuntos
Cobalto/química , Complexos de Coordenação/síntese química , Bases de Schiff/química , Triazinas/síntese química , DNA/metabolismo , Guanidinas/química , Ligantes , Simulação de Acoplamento Molecular , Ácido Pirúvico/química , Soroalbumina Bovina/metabolismo , Solubilidade , Análise Espectral
18.
Vet Parasitol ; 149(3-4): 158-66, 2007 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-17890012

RESUMO

Clinical neosporosis was diagnosed in a litter of five pups born to a Beagle bitch from Virginia, USA. Four of the pups developed limb weakness starting at 4 weeks of age. The dogs were suspected to have neosporosis based on clinical signs and empirically treated with Clindamycin (75 mg, oral, twice daily, total 150 mg) starting at 9 weeks of age and the dosage was doubled at 13 weeks of age. Antibodies to Neospora caninum were detected in sera of the dam and pups when first tested serologically at the age of 4 months. The owner donated the pup with the worst clinical signs and the dam for research; both dogs were euthanized. Viable N. caninum was isolated in gamma interferon gene knock out (KO) mice and in cell culture from the pup killed at 137 days of age. Tissue cysts, but no tachyzoites, were found in histological sections of brain and muscles. The isolate was also identified as N. caninum by PCR and sequence analysis and designated NC-9. N. caninum was neither isolated by bioassay in KO mice nor found in histological sections of tissues of the bitch. Clinical signs in the remaining three pups improved considerably after a 6-month treatment with Clindamycin; N. caninum antibody titers were still persistent in these pups at 23 months of age. Results indicate that medication with Clindamycin can improve clinical condition but not eliminate N. caninum infection.


Assuntos
Coccidiose/veterinária , Doenças do Cão/parasitologia , Neospora/genética , Animais , Anticorpos Antiprotozoários/sangue , Antiprotozoários/uso terapêutico , Sequência de Bases , Clindamicina/uso terapêutico , Coccidiose/diagnóstico , Coccidiose/tratamento farmacológico , Coccidiose/parasitologia , DNA Intergênico/genética , Doenças do Cão/diagnóstico , Doenças do Cão/tratamento farmacológico , Cães , Dados de Sequência Molecular
19.
Vet Parasitol ; 148(3-4): 207-12, 2007 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-17656021

RESUMO

Clinical toxoplasmosis in chickens (Gallus domesticus) has been rarely reported in literature. Here we report that three chickens on a farm in Illinois developed neurological signs. One of these chickens was examined postmortem and it had non-suppurative encephalitis with numerous Toxoplasma gondii tachyzoites and tissue cysts. The identity of the protozoa was confirmed immunohistochemically by staining with T. gondii specific antibodies, and by transmission electron microscopy. The owner of the 3 chickens donated all 11 remaining chickens and a goose on his property for the present study. All 11 chickens and a goose were euthanized, and blood, heart, brain, and 1 leg were obtained for T. gondii examination. Antibodies to T. gondii were found in sera of all chickens with titers of 1:40 in one, 1:320 in three, and 1:640 or higher in seven chickens tested by the modified agglutination test (MAT). The goose had a MAT titer of 1:320. For isolation of T. gondii, whole heart and brain and 50 g of leg muscles were digested in an acid-pepsin solution and bioassayed in four mice for each tissue. Viable T. gondii was isolated from tissues of all 11 chickens and the goose. Genotyping of these 12 T. gondii isolates using polymorphism at the genetic loci SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, a new SAG2 and Apico revealed that all isolates had Type II alleles at all loci, indicating these T. gondii isolates belong to the predominant clonal Type II lineages. This is the first report of isolation of viable T. gondii from a domestic goose (Anser anser).


Assuntos
Galinhas/parasitologia , Gansos/parasitologia , Doenças das Aves Domésticas , Toxoplasma/genética , Toxoplasmose Animal , Animais , Anticorpos Antiprotozoários/sangue , Anticorpos Antiprotozoários/metabolismo , Cérebro/parasitologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Genótipo , Illinois , Camundongos , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/patologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/diagnóstico , Toxoplasmose Animal/parasitologia , Toxoplasmose Animal/patologia
20.
Vet Parasitol ; 146(3-4): 341-6, 2007 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-17442491

RESUMO

The prevalence of Toxoplasma gondii in 86 street dogs from Sri Lanka was determined. Antibodies to T. gondii were assayed by the modified agglutination test (MAT) and found in 58 (67.4%) of 86 dogs with titers of 1:20 in eight, 1:40 in four, 1:80 in 10, 1:160 in 22, 1:320 in six, 1:640 in five, and 1:1280 or higher in three. Hearts, tongues, and brains (either separately or pooled) of 50 dogs with MAT titers of 1:40 were selected for isolation of T. gondii by bioassays in mice. For bioassays, canine tissues were digested in pepsin and homogenates were inoculated subcutaneously into mice; the mice receiving canine tissues were examined for T. gondii infection. In all, T. gondii was isolated from 23 dogs. Interestingly, dog organs varied in their capacity to induce T. gondii infection in mice, muscles producing more positive results than the brain. The T. gondii isolates obtained from 23 seropositive dogs were PCR-RFLP genotyped using polymorphisms at 10 nuclear markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, a new SAG2, and an apicoplast marker Apico. Mixed infection with two genotypes was observed in one dog. Four genotypes were revealed, including three unique genotypes in addition to one belonging to the predominant Type III lineage. The 24 isolates were designated as TgDgSl 1-24.


Assuntos
Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Toxoplasma/genética , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/parasitologia , Animais , Cães , Genótipo , Camundongos , Prevalência , Sri Lanka/epidemiologia , Toxoplasma/classificação , Toxoplasma/isolamento & purificação
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