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1.
bioRxiv ; 2023 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-37961580

RESUMO

The neuromuscular junction (NMJ) is the linchpin of nerve-evoked muscle contraction. Broadly considered, the function of the NMJ is to transduce a nerve action potential into a muscle fiber action potential (MFAP). Efficient information transfer requires both cholinergic signaling, responsible for the generation of endplate potentials (EPPs), and excitation, the activation of postsynaptic voltage-gated sodium channels (Nav1.4) to trigger MFAPs. In contrast to the cholinergic apparatus, the signaling pathways that organize Nav1.4 and muscle fiber excitability are poorly characterized. Muscle-specific kinase (MuSK), in addition to its Ig1 domain-dependent role as an agrin-LRP4 receptor, is also a BMP co-receptor that binds BMPs via its Ig3 domain and shapes BMP-induced signaling and transcriptional output. Here we probed the function of the MuSK-BMP pathway at the NMJ using mice lacking the MuSK Ig3 domain ('ΔIg3-MuSK'). Synapses formed normally in ΔIg3-MuSK animals, but the postsynaptic apparatus was fragmented from the first weeks of life. Anatomical denervation was not observed at any age examined. Moreover, spontaneous and nerve-evoked acetylcholine release, AChR density, and endplate currents were comparable to WT. However, trains of nerve-evoked MFAPs in ΔIg3-MuSK muscle were abnormal as revealed by increased jitter and blocking in single fiber electromyography. Further, nerve-evoked compound muscle action potentials (CMAPs), as well as twitch and tetanic muscle torque force production, were also diminished. Finally, Nav1.4 levels were reduced at ΔIg3-MuSK synapses but not at the extrajunctional sarcolemma, indicating that the observed excitability defects are the result of impaired localization of this voltage-gated ion channel at the NMJ. We propose that MuSK plays two distinct roles at the NMJ: as an agrin-LRP4 receptor necessary for establishing and maintaining cholinergic signaling, and as a BMP co-receptor required for maintaining proper Nav1.4 density, nerve-evoked muscle excitability and force production. The MuSK-BMP pathway thus emerges as a target for modulating excitability and functional innervation, which are defective in conditions such as congenital myasthenic syndromes and aging.

2.
J Intellect Disabil Res ; 63(8): 947-956, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30775832

RESUMO

BACKGROUND: Tuberous sclerosis complex (TSC) is a complex multisystem genetic disorder. Approximately 84% of people with TSC have epilepsy. However, there is little literature available regarding families' experiences with TSC and seizure management. Therefore, the aim of the current study was to explore families' positive and negative experiences, and attitudes towards TSC, epilepsy and medical management of seizures. METHODS: Framework analysis informed an open exploration of families' experiences with TSC, epilepsy and medical management of seizures. Using structured interviews, 11 parents of people with TSC and 2 people with TSC were interviewed, providing the data set for transcription and thematic analysis. RESULTS: 'TSC rules our life' overarched three subordinate themes: 'Our normal', 'Burnout' and 'Seizure management has given us our life back'. Families had to adapt to the normality of needing to constantly supervise their child even as they become an adult. They express a feeling of fear particularly of seizures, and this has impact throughout the family. There are frequent expressions of exhaustion and struggling to fight for access and support. There are some positives and cautious hope with the gaining of control from seizures as being able to predict or plan improves activity and participation. These interviews provided a rich insight into the lives of those with TSC and their families. CONCLUSION: There are exciting developments with respect to scientific understanding of the pathophysiology of TSC, which opens opportunity for new treatments. Holistic family centred health care and practical support (e.g. opportunities for parental respite) is as important as medical intervention. As TSC is such a complex condition, there is a need for specialist clinics and TSC-specific research.


Assuntos
Epilepsia/tratamento farmacológico , Família/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Esclerose Tuberosa/terapia , Adolescente , Adulto , Criança , Gerenciamento Clínico , Epilepsia/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Esclerose Tuberosa/complicações , Adulto Jovem
3.
Health Educ Res ; 33(1): 81-88, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29309599

RESUMO

Text-based interventions are effective for smoking cessation, but have not been tested in rural older adults. The purpose of this study was to compare the feasibility, acceptability and preliminary efficacy of a text-based Scheduled Gradual Reduction (SGR) program to a non-SGR text messaging support condition among rural older adults. Adults over 60 years were randomized to either: (i) the SGR program (n = 20), a text-based program to reduce smoking over 4-weeks plus text-based support messages; or (ii) control (n = 20), receipt of text-based support messages only. Participants completed surveys at baseline and end of program to assess feasibility and acceptability of the intervention, and biochemically validated 7-day point prevalence cessation was assessed at end of treatment. Most participants (81%) reported reading all the messages they received. Participants found both interventions useful in quitting smoking (SGR = 57%, Control = 63%) and would recommend it to a friend (SGR = 72%, Control = 79%). Although not statically significant, the SGR group had a higher rate of biochemically validated cessation (SGR = 15%, Control = 5%, Cohen d = 0.67). Among those still smoking, the median percent reduction in cigarettes was 33.3% for both groups. Text-based cessation interventions are feasible, acceptable and can be easily disseminated to rural older adult tobacco users.


Assuntos
População Rural , Abandono do Hábito de Fumar/métodos , Envio de Mensagens de Texto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos , Fatores de Tempo
4.
Prev Vet Med ; 120(2): 232-235, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25890821

RESUMO

Neosporosis, caused by the intracellular protozoan Neospora caninum, is a major cause of abortion and reproductive failure in cattle worldwide. The principal route of transmission of neosporosis is via in utero infection of the offspring. There is no effective prophylactic treatment or vaccine available against bovine neosporosis. A N. caninum NcIs491 isolate was examined for its ability to immunize and reduce abortions in naturally infected dairy cows under field conditions. N. caninum-seropositive pregnant dams were inoculated with 10(8) live tachyzoites during mid-term pregnancy. A total of 520 N. caninum seropositive dams were included in this study, of these, 146 were immunized and 374 cows served as a non-vaccinated control group. A significantly lower incidence of abortion was observed in vaccinated compared to non-vaccinated cows, 16 and 26% respectively (P=0.01), with a vaccine efficacy of 39%. However, the number of seropositive offspring remained similar in both groups. Overall, this field trial suggests that vaccination with live N. caninum tachyzoites should be considered as an effective measure to reduce abortions caused by neosporosis in naturally infected cows.


Assuntos
Aborto Animal/prevenção & controle , Doenças dos Bovinos/prevenção & controle , Coccidiose/veterinária , Neospora/imunologia , Vacinas Protozoárias/uso terapêutico , Vacinação/veterinária , Aborto Animal/parasitologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Feminino , Israel , Gravidez , Vacinas Atenuadas/uso terapêutico
5.
Parasitology ; 139(3): 317-23, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22075976

RESUMO

The aim of this study was to compare the genetic diversity of the single copy Bv80 gene sequences of Babesia bovis in populations of attenuated and virulent parasites. PCR/ RT-PCR followed by cloning and sequence analyses of 4 attenuated and 4 virulent strains were performed. Multiple fragments in the range of 420 to 744 bp were amplified by PCR or RT-PCR. Cloning of the PCR fragments and sequence analyses revealed the presence of mixed subpopulations in either virulent or attenuated parasites with a total of 19 variants with 12 different sequences that differed in number and type of tandem repeats. High levels of intra- and inter-strain diversity of the Bv80 gene, with the presence of mixed populations of parasites were found in both the virulent field isolates and the attenuated vaccine strains. In addition, during the attenuation process, sequence analyses showed changes in the pattern of the parasite subpopulations. Despite high polymorphism found by sequence analyses, the patterns observed and the number of repeats, order, or motifs found could not discriminate between virulent field isolates and attenuated vaccine strains of the parasite.


Assuntos
Babesia bovis/genética , Babesiose/parasitologia , Sequência de Aminoácidos , Animais , Babesia bovis/imunologia , Babesia bovis/patogenicidade , Babesiose/imunologia , Babesiose/prevenção & controle , Bovinos , Clonagem Molecular , Escherichia coli , Variação Genética , Dados de Sequência Molecular , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Vacinas Protozoárias , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Análise de Sequência de DNA , Sequências de Repetição em Tandem , Vacinas Atenuadas , Virulência
6.
Vet Microbiol ; 143(2-4): 277-83, 2010 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-20036077

RESUMO

The present study was aimed to identify msp2 pseudogenes and MSP2 variants in the vaccine Anaplama centrale strain. Five msp2 pseudogenes were identified in the A. centrale genome, and multiple MSP2 variants that emerged during both acute and persistent infection were detected. The pseudogene copies of msp2 were truncated; they contained a central hypervariable region flanked by short portions of the 5' and 3' conserved regions. Alignment of the hypervariable region sequence of the expression site of MSP2 variants with msp2 pseudogenes showed that MSP2 variants are generated by two mechanisms, previously described in Anaplasma marginale: (i) recombination of the whole pseudogene into the single msp2 expression site, and (ii) recombination of small segments of pseudogenes into the expression site by segmental gene conversion. The present study showed that the A. centrale MSP2 variants and the msp2 pseudogene repertoire were different from those reported for A. marginale. Unique MSP2 variants and pseudogenes identified in the vaccine strain allow the A. centrale-vaccinated cattle to be superinfected with the field strains of A. marginale. The knowledge gained in the present study on the mechanisms of antigenic variations in the vaccine strain of A. centrale is a further step in the development of a new generation vaccine against anaplasmosis.


Assuntos
Anaplasma centrale/genética , Anaplasma centrale/metabolismo , Proteínas da Membrana Bacteriana Externa/genética , Pseudogenes/genética , Sequência de Aminoácidos , Anaplasmose/microbiologia , Anaplasmose/prevenção & controle , Animais , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/metabolismo , Vacinas Bacterianas/imunologia , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/prevenção & controle , Regulação Bacteriana da Expressão Gênica/fisiologia , Genoma Bacteriano , Genômica , Dados de Sequência Molecular , Compostos Organometálicos
7.
Vet Microbiol ; 134(3-4): 254-60, 2009 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-18823724

RESUMO

The cattle rickettsia Anaplasma marginale is distributed worldwide and is transmitted by about 20 tick species, but only Rhipicephalus simus, a strictly African tick species, has been shown to transmit the vaccine strain of A. centrale. The aim of the present study was to examine transmission of field strains of A. marginale and of the vaccine strain of A. centrale by three tick species -Hyalomma excavatum, Rhipicephalus sanguineus and Rhipicephalus (Boophilus) annulatus - to susceptible calves. Two genetically distinct Israeli field strains of A. marginale, tailed and non-tailed (AmIsT and AmIsNT, respectively), were efficiently transmitted by R. sanguineus, whereas H. excavatum transmitted only the tailed isolate, and R. (Boophilus) annulatus did not transmit A. marginale. None of the three tick species transmitted A. centrale. By means of msp1a primers in PCR assays, amplicons of similar sizes were obtained from either A. marginale-infected calves that were used for acquisition feeding, from R. sanguineus fed on the infected calves, or from calves to which anaplasmosis had been successfully transmitted by these ticks. Although an A. centrale-specific fragment was amplified from salivary glands of R. sanguineus, no transmission to susceptible cattle occurred during 3 months of observation, and anaplasmosis was not induced in splenectomized calves that were subinoculated with blood from calves on which R. sanguineus had fed.


Assuntos
Anaplasma centrale/imunologia , Anaplasma marginale/imunologia , Anaplasmose/imunologia , Vacinas Bacterianas/imunologia , Carrapatos , Animais , Bovinos , Feminino , Masculino , Esplenectomia
8.
Vet Microbiol ; 136(1-2): 54-60, 2009 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-19081688

RESUMO

The present study was aimed to demonstrate genotypic diversity of Anaplama marginale in infected beef herds grazing within anaplasmosis endemic regions. The genotypic diversity was identified among different herds, within each herd, and also within single animals. The Israeli strains revealed unique characteristics of MSP1a repeats and, in addition to the published repeats, six new tandem repeats designated Is1-5, and Is9 were identified. The superinfections of individual Anaplama centrale vaccinated animals with two genotypically different A. marginale strains were detected. Six out of 43 vaccinated animals in the G herd were each infected with two A. marginale strains carrying two distinct genotypes; in this herd the follow-up during years 2003-2007 demonstrated that several animals carried different msp1a genotypes at different time points. Coinfection with two different genotypes of A. marginale in A. centrale vaccinated cattle was observed in another herd, as well. It appears that A. marginale is composed of a heterogeneous changing bacterial population that evolves in the host or, the genotypic diversity implies high transmission intensity by the vector, or both. Learning how this diversity is generated and identification of distinct A. marginale strains coupled with high sequence variation of MSP1a will aid in understanding Anaplasma transmission and disease development.


Assuntos
Anaplasma marginale/genética , Anaplasmose/microbiologia , Proteínas da Membrana Bacteriana Externa/genética , Doenças dos Bovinos/microbiologia , Anaplasma marginale/crescimento & desenvolvimento , Animais , Sequência de Bases , Southern Blotting/veterinária , Bovinos , Clonagem Molecular , DNA Bacteriano/química , DNA Bacteriano/genética , Variação Genética , Repetições de Microssatélites , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA
9.
Vet Microbiol ; 130(3-4): 277-84, 2008 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-18387757

RESUMO

Bovine anaplasmosis, caused by Anaplasma marginale, the intraerythrocytic rickettsia, is controlled by vaccination with live Anaplasma marginale ss centrale (A. centrale), a subspecies of relatively low pathogenicity. We have experimentally demonstrated that an animal primarily infected with A. marginale, or with the related vaccine subspecies A. centrale can be infected with the heterologous subspecies, and carries both bacteria. The co-infection was detected in experimentally cross-infected calves for up to 3 months after the last inoculation with the heterologous subspecies. The occurrence of characteristic cyclic rickettsemia of A. centrale and A. marginale was observed by examination of Giemsa-stained blood smears, or by the presence of specific rickettsial DNA confirmed in PCR assays based on specific msp1a and msp4 for A. marginale, and on specifically designed msp3 and msp4 primers for A. centrale. Sequence analysis of msp4-specific fragments for each subspecies revealed the presence of dual infection in both calves on days 30 and 60 after cross-inoculation with the heterologous Anaplasma subspecies. The experimental cross-infection of calves clearly demonstrated that the concept of "infection exclusion" does not apply to Anaplasma infection in cattle; as there was no infection exclusion of A. marginale in A. centrale-infected cattle, and vice versa. The present results confirmed our previous findings that cattle grazing in an anaplasmosis-endemic field were subject to concomitant infection with both the vaccine A. centrale and the field A. marginale strains.


Assuntos
Anaplasma centrale/imunologia , Anaplasma marginale/imunologia , Anaplasmose/microbiologia , Vacinas Bacterianas/imunologia , Animais , Bovinos , DNA Bacteriano/sangue , Esplenectomia
10.
Community Genet ; 11(4): 224-33, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18417970

RESUMO

This study explored whether reactions to the Cancer Genetics Network (CGN) or CGN enrollment differed by receipt of a standard informational brochure versus a targeted version addressing factors previously associated with African Americans' health behavior decisions and research participation. The 262 participants, identified through tumor registries or clinic contacts, were mailed brochures and completed phone interviews. When asked whether - based on the brochure - they were or were not 'leaning toward' CGN enrollment, about 75% of both standard and targeted groups reported leaning toward. When given the opportunity at the end of the interview, 68% enrolled in the CGN. Trust was strongly related to enrollment. Less education, less satisfaction with cancer care, and individualistic rather than collective orientation were associated with lower trust. Education was also bivariately associated with enrollment, but mediation analysis indicated that the operational mechanism of education's influence on enrollment was through trust.


Assuntos
Negro ou Afro-Americano/psicologia , Neoplasias/psicologia , Participação do Paciente , Sistema de Registros , Adulto , Negro ou Afro-Americano/genética , Idoso , Idoso de 80 Anos ou mais , Atitude Frente a Saúde , Ensaios Clínicos como Assunto , Estudos de Coortes , Escolaridade , Feminino , Pesquisa em Genética , Humanos , Masculino , Oncologia , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/terapia , Confiança
11.
Vaccine ; 26 Suppl 6: G14-6, 2008 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-19178887

RESUMO

In Uzbekistan, 1984 cattle were vaccinated with the TAU-219 autochthonous live Theileria annulata vaccine under field conditions. There were no post-vaccination reactions recorded in calves vaccinated with 10 times the recommended dose, under semi-field conditions. After vaccination 53.9% of the vaccinates developed fever over 39.5 degrees C that lasted for a few days, but none developed clinical theileriosis or required drug treatment during the 3-week follow-up. The numbers of animals in which piroplasms were detected before and after vaccination were similar (7.15% and 7.25%, respectively), indicating previous exposure to T. annulata tick infection. Following vaccination none of the 241 pregnant cows aborted. Milk production during 30-45 days was similar in non-vaccinated and vaccinated cows, at about 5.2-5.9L/day. During 1999-2006 a total of 11,000 field-grazing cattle were safely vaccinated in Uzbekistan.


Assuntos
Doenças dos Bovinos/prevenção & controle , Complicações Parasitárias na Gravidez/veterinária , Vacinas Protozoárias , Theileria annulata/imunologia , Theileriose/prevenção & controle , Aborto Animal/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/imunologia , Feminino , Gravidez , Complicações Parasitárias na Gravidez/imunologia , Complicações Parasitárias na Gravidez/prevenção & controle , Vacinas Protozoárias/administração & dosagem , Vacinas Protozoárias/efeitos adversos , Vacinas Protozoárias/imunologia , Theileriose/parasitologia , Resultado do Tratamento , Uzbequistão/epidemiologia , Vacinação/veterinária , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/imunologia
12.
Vet Parasitol ; 149(3-4): 167-71, 2007 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-17850972

RESUMO

First Israeli Neospora caninum isolates were obtained from brain tissues of aborted fetuses (NcIs491 and NcIs580) from dairy farms endemic for neosporosis and maintaining cattle on zero grazing. Tissues from different parts of the fetus brains were used to infect Vero cells. Tachyzoites of N. caninum were first observed in cultures from days 30 and 32 after infection. To confirm the identity of the isolated parasites, DNA extracts from brains and cultures were tested by PCR with specific primers based on the Nc5 gene. Specific fragments were amplified by PCR from infected cultures of both fetuses on day 25. Susceptible seronegative gerbils (Meriones tristrami) were inoculated intraperitoneally with 10(3) to 10(5) tenfold dilutions of subculture tachyzoites. The inoculated gerbils developed specific antibodies to N. caninum, with end-point serum dilution of 1:4096 in the IFA assay, whereas no neurological signs or deaths were seen during 4 months of observation.


Assuntos
Criação de Animais Domésticos , Doenças dos Bovinos/parasitologia , Coccidiose/veterinária , Neospora/isolamento & purificação , Feto Abortado/parasitologia , Aborto Animal , Animais , Anticorpos Antiprotozoários , Bovinos , Coccidiose/diagnóstico , Coccidiose/parasitologia , Indústria de Laticínios , Feminino , Israel
13.
Vet Parasitol ; 146(3-4): 221-6, 2007 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-17368728

RESUMO

The virulence of an Uzbek isolate of Babesia bigemina, obtained from infected Boophilus annulatus ticks from an endemic area in Uzbekistan, was attenuated for immunization of cattle with autochthonous calf- or culture-derived parasites in Uzbekistan. After four "slow passages" in vivo the virulence was reduced, as evidenced by the response of calves inoculated with an experimental live frozen vaccine produced from the following passage. The vaccine was safe and protective against homologous virulent challenge under laboratory conditions. The culture-derived experimental vaccine was produced from cultures initiated after 3 passages in vivo followed by 22 passages in vitro. The cultured parasites did not elicit any clinical sign, but inoculated calves seroconverted following vaccination and were protected against the virulent homologous challenge. Both calf- and culture-derived vaccines were safe for cattle grazing in an endemic area in Uzbekistan. Despite the high polymorphism of B. bigemina, as reported from various geographical regions, the Central Asian strain was attenuated similarly to those that form the basis of the existing live B. bigemina vaccines in other parts of the world.


Assuntos
Babesia/imunologia , Babesiose/prevenção & controle , Vacinas Protozoárias/imunologia , Animais , Anticorpos Antiprotozoários/sangue , Babesia/isolamento & purificação , Babesia/patogenicidade , Bovinos , Imunização , Masculino , Uzbequistão/epidemiologia , Virulência
14.
Bioorg Med Chem Lett ; 17(9): 2643-8, 2007 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-17314044

RESUMO

This report describes the effect of replacing the central basic amine present in many known 5-HT(2A) ligands with an aromatic residue. We targeted the isomeric phenethylpyridines 2 and 3 and these compounds proved to be excellent leads, possessing good 5-HT(2A) receptor binding affinity and selectivity over the 5-HT(2C) subtype. Optimization of one isomer led to the identification of 25, a compound with sub-nanomolar 5-HT(2A) affinity and selectivity over 5-HT(2C) of greater than 4600-fold.


Assuntos
Química Farmacêutica/métodos , Piridinas/química , Piridinas/síntese química , Receptor 5-HT2A de Serotonina/química , Antagonistas da Serotonina/química , Antagonistas da Serotonina/síntese química , Animais , Desenho de Fármacos , Humanos , Cinética , Ligantes , Modelos Químicos , Conformação Molecular , Piridinas/farmacologia , Ratos , Antagonistas da Serotonina/farmacologia , Sulfonas/química
15.
Vet Microbiol ; 113(1-2): 55-62, 2006 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-16300909

RESUMO

A reverse line blot hybridization (RLB) one-stage nested PCR (nPCR) for Anaplasma centrale and a nested PCR for Anaplasma marginale were used to detect infected cattle grazing within an endemic region in Israel. A novel set of PCR primers and oligonucleotide probes based on a 16S ribosomal RNA gene was designed for RLB detection of both Anaplasma species, and the performance of the molecular assays compared. The immunofluorescent antibody test (IFA) was used to detect antibodies to both Anaplasma species, whereas, a highly sensitive and specific competitive enzyme-linked immunosorbent assay (cELISA) was used to detect antibodies in A. centrale-vaccinated cattle. The RLB and the nested PCR procedures showed bacteremia with sensitivity of 50 infected erythrocytes per milliliter. Up to 93% of the A. centrale vaccinates carried specific antibodies that were detected by cELISA, and up to 71% of the vaccinated cattle were found to be naturally infected with A. marginale according to the PCR and the RLB assays. Nevertheless, no severe outbreaks of A. marginale infection occurred among vaccinated herds in this endemic region. It appears that both, molecular tools and serology are useful for evaluation of the vaccine efficacy. In the light of wide natural field infection with A. marginale, strong recommendations to continue the A. centrale vaccination program regime will continue until a new generation of non-blood-based vaccine will be developed.


Assuntos
Anaplasma centrale/imunologia , Anaplasma centrale/isolamento & purificação , Anaplasma marginale/isolamento & purificação , Anaplasmose/diagnóstico , Doenças dos Bovinos/diagnóstico , Anaplasma centrale/genética , Anaplasma marginale/genética , Anaplasmose/microbiologia , Anaplasmose/prevenção & controle , Animais , Anticorpos Antibacterianos/sangue , Proteínas da Membrana Bacteriana Externa/genética , Vacinas Bacterianas/imunologia , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/prevenção & controle , Primers do DNA/química , Sondas de DNA/química , DNA Bacteriano/química , Doenças Endêmicas/veterinária , Ensaio de Imunoadsorção Enzimática/métodos , Israel , Dados de Sequência Molecular , Reação em Cadeia da Polimerase/veterinária , Sensibilidade e Especificidade
16.
Onderstepoort J Vet Res ; 73(4): 251-5, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17283724

RESUMO

This paper describes the first successful in vitro cultivation of a South African isolate of an Anaplasma sp., initially thought to be Anaplasma marginale, in the continuous tick cell line IDE8. Blood from a bovine naturally infected with A. marginale kept on the farm Kaalplaas (28 degrees 08' E, 25 degrees 38' S) was collected, frozen, thawed and used as inoculum on confluent IDE8 cell cultures. Twenty days after culture initiation small intracellular colonies were detected in a Cytospin smear prepared from culture supernatant. Cultures were passaged on Day 34. Attempts to infect IRE/CTVM18 cell cultures with the Kaalplaas isolate derived from IDE8 cultures failed, whereas a reference stock of A. marginale from Israel infected IRE/CTVM18 tick cell cultures. Attempts to infect various mammalian cell lines (BA 886, SBE 189, Vero, L 929, MDBK) and bovine erythrocytes, kept under various atmospheric conditions, with tick cell-derived Anaplasma sp. or the Israeli strain of A. marginale failed. Molecular characterization revealed that the blood inoculum used to initiate the culture contained both A. marginale and Anaplasma sp. (Omatienne) whereas the organisms from established cultures were only Anaplasma sp. (Omatjenne).


Assuntos
Anaplasma/crescimento & desenvolvimento , Eritrócitos/microbiologia , Ixodes/microbiologia , Anaplasma/classificação , Anaplasma/isolamento & purificação , Animais , Bovinos , Células Cultivadas , DNA Bacteriano/química , Eritrócitos/ultraestrutura , Ixodes/citologia , Microscopia Eletrônica/veterinária , Filogenia , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/veterinária
17.
Bioorg Med Chem Lett ; 15(16): 3665-9, 2005 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15993598

RESUMO

Incorporation of fluorine at the 4-position of an existing series of sulfonyl piperidine 5-HT2A antagonists gave compounds with increased selectivity over the IKr potassium channel. This work led to the identification of 3b, a compound that gave no increase in QTc in the anesthetized dog up to plasma levels as high as 148 microM. Furthermore, 3b has been shown to increase slow-wave sleep bout duration and to decrease the number of awakenings in rats, indicating the potential utility of 5-HT2A antagonists in the treatment of insomnia.


Assuntos
Piperidinas/farmacologia , Piperidinas/uso terapêutico , Antagonistas do Receptor 5-HT2 de Serotonina , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Animais , Cães , Avaliação Pré-Clínica de Medicamentos , Ligantes , Estrutura Molecular , Piperidinas/síntese química , Ratos , Relação Estrutura-Atividade , Fatores de Tempo
18.
Vet Parasitol ; 129(3-4): 235-42, 2005 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15845278

RESUMO

Two separate groups of Bos taurus bulls, one of 106 and the second of 27 animals, imported to Israel from areas free of Babesia bovis and Babesia bigemina, were vaccinated against babesiosis with a bivalent live attenuated vaccine. In light of the fact that routine vaccination is recommended at the weaning age, these bulls--of highly susceptible breeds--were kept under close surveillance to prevent losses that might be caused by severe clinical reactions to their vaccination at the age of 16-18 months. Seven days after vaccination, about one-third of the 106 bulls in the first group developed clinical signs of B. bigemina infection, which peaked at day 9, and then diminished from day 11, when the patent period known for B. bovis infection was observed. Because of the severe clinical responses a total of 36% of the bulls required babesicidal treatment. Despite the treatment Babesia were not sterilized: 33 and 68% of the animals remained PCR positive for B. bigemina and B. bovis, respectively. To mitigate the severe responses to vaccination, the 27 bulls of the second group were vaccinated in two-steps: they were inoculated initially with avirulent culture-derived parasites and then vaccinated with the conventional donor-derived vaccine a month later. None of the bulls in the latter group developed clinical babesiosis, all were serologically positive to B. bigemina, and 67% showed seroconversion to B. bovis. In light of the experience described here, it is suggested that sensitive older cattle be vaccinated against babesiosis by priming them with avirulent in vitro-cultured parasites and then inoculating them with the conventional donor-derived vaccines.


Assuntos
Babesia/imunologia , Babesiose/veterinária , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/parasitologia , Vacinas Protozoárias/imunologia , Vacinação/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Babesia/genética , Babesiose/imunologia , Babesiose/parasitologia , Babesiose/prevenção & controle , Temperatura Corporal/imunologia , Bovinos , Doenças dos Bovinos/imunologia , DNA de Protozoário/química , DNA de Protozoário/genética , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Hematócrito/veterinária , Israel , Masculino , Parasitemia/imunologia , Parasitemia/parasitologia , Parasitemia/veterinária , Reação em Cadeia da Polimerase/veterinária , Vacinas Protozoárias/efeitos adversos , Vacinas Protozoárias/uso terapêutico , Vacinação/efeitos adversos , Vacinação/métodos , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/uso terapêutico
20.
Vet Parasitol ; 115(3): 247-55, 2003 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-12935740

RESUMO

A field isolate of Theileria annulata (Uzbek strain) was obtained from calves infected by Hyalomma anatolicum ticks collected from an endemic region in Uzbekistan. Schizont-infected bovine cells that had been established and propagated in cell culture were examined for attenuation both in vivo, by inoculating cells from various passages into calves, and in vitro for metalloproteinase activity. During serial subcultivation a gradual reduction in virulence and in enzyme activity in cells infected with the Uzbek strain were observed. Complete attenuation of the Uzbek isolate was obtained at about passage 80, and only traces of proteolysis were detected in gelatin substrate gels. In contrast, there was no direct correlation between virulence and enzyme levels in an Israeli strain. While schizonts of the Israeli strain were completely attenuated at passage 80, proteolysis in the substrate gels was detected up to passage 197. Solid immunity was observed in calves immunized with attenuated T. annulata schizonts of the Uzbek strain upon challenge with the homologous H. excavatum sporozoites. For a strain to be used for vaccine production, it appears that animal inoculation still remains the most reliable method to assess the degree of attenuation and protection.


Assuntos
Doenças dos Bovinos/parasitologia , Peptídeo Hidrolases/metabolismo , Theileria annulata/enzimologia , Theileriose/parasitologia , Doenças Transmitidas por Carrapatos/veterinária , Animais , Anticorpos Antiprotozoários/sangue , Bovinos , Doenças dos Bovinos/imunologia , Células Cultivadas , Eletroforese em Gel de Poliacrilamida/veterinária , Feminino , Imunofluorescência/veterinária , Theileria annulata/patogenicidade , Theileriose/sangue , Theileriose/imunologia , Doenças Transmitidas por Carrapatos/imunologia , Doenças Transmitidas por Carrapatos/parasitologia , Virulência
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