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1.
J Am Heart Assoc ; 10(21): e021934, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34713713

RESUMO

Background Trimethylamine-N-oxide (TMAO) is a small molecule derived from the metabolism of dietary nutrients by gut microbes and contributes to cardiovascular disease. Plasma TMAO increases following consumption of red meat. This metabolic change is thought to be partly because of the expansion of gut microbes able to use nutrients abundant in red meat. Methods and Results We used data from a randomized crossover study to estimate the degree to which TMAO can be estimated from fecal microbial composition. Healthy participants received a series of 3 diets that differed in protein source (red meat, white meat, and non-meat), and fecal, plasma, and urine samples were collected following 4 weeks of exposure to each diet. TMAO was quantitated in plasma and urine, while shotgun metagenomic sequencing was performed on fecal DNA. While the cai gene cluster was weakly correlated with plasma TMAO (rho=0.17, P=0.0007), elastic net models of TMAO were not improved by abundances of bacterial genes known to contribute to TMAO synthesis. A global analysis of all taxonomic groups, genes, and gene families found no meaningful predictors of TMAO. We postulated that abundances of known genes related to TMAO production do not predict bacterial metabolism, and we measured choline- and carnitine-trimethylamine lyase activity during fecal culture. Trimethylamine lyase genes were only weakly correlated with the activity of the enzymes they encode. Conclusions Fecal microbiome composition does not predict systemic TMAO because, in this case, gene copy number does not predict bacterial metabolic activity. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01427855.


Assuntos
Microbiota , Adulto , Bactérias/metabolismo , Colina/metabolismo , Estudos Cross-Over , Dieta , Fezes , Microbioma Gastrointestinal , Humanos , Liases/metabolismo , Metilaminas/sangue
2.
Neurol Sci ; 40(2): 261-268, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30368695

RESUMO

OBJECTIVE: Neurological symptoms in patients with cat-scratch disease (CSD) have been rarely reported. The aim of this study is to analyze the frequency of neurological CSD (NCSD) and describe the disease clinical presentation, management and outcome. MATERIAL AND METHODS: We retrospectively selected patients with a CSD syndrome and Bartonella IgG titers > 1:256. Data regarding epidemiological, clinical, management, and follow-up features were analyzed and discussed. A comparison between NCSD and non-neurological CSD (NNCSD) was established. RESULTS: Thirty-nine CSD patients were selected. NCSD frequency was 10.25%. No children were found affected in the NCSD group. A 65.7% of NNCSD and the entirety of the NCSD group had a history of cat exposure. Immunosuppression was only present in the NNCSD group (8.6%). NCSD presentations were as follows: isolated aseptic meningitis (25%), neuroretinitis (50%), and isolated optic neuritis (25%). A greater proportion of patients in the NCSD group had fever and raised levels of acute phase reactants and white blood cells. 85.7% of NNCSD had a complete recovery, whereas only 50% of the NCSD patients experienced a full recovery. CONCLUSION: NCSD may be a distinctive group compared to NNCSD due to its later age of presentation, the more intense systemic response, and the poorer outcome.


Assuntos
Bartonella henselae , Doença da Arranhadura de Gato/epidemiologia , Doença da Arranhadura de Gato/fisiopatologia , Adolescente , Adulto , Idoso , Antibacterianos/uso terapêutico , Doença da Arranhadura de Gato/diagnóstico , Doença da Arranhadura de Gato/terapia , Feminino , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
3.
Rev Clin Esp ; 211(2): 85-9, 2011 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-21316657

RESUMO

OBJECTIVE: To describe patients diagnosed with hematoma of the rectus abdominis (HRA) muscle. MATERIAL AND METHODS: A retrospective analysis of patients diagnosed with HRA over the past 8 years in our center. RESULTS: A total of 17 patients (9 women) with mean age of 73 years were included in the study. In 52% of the cases the HRA was the cause of hospitalization. Anticoagulant therapy was documented in 70%. More than half of patients treated with low molecular weight heparin had renal insufficiency. In the group receiving oral anticoagulants (OA), 86% had INR greater than 4. Paroxysmal cough appeared in 13. The most common presentation was abdominal pain and palpable mass. CT scan sensitivity was superior to that of the ultrasound. The most common location was the lower right. Treatment was conservative in all but one. Two patients died. Mean decrease in hemoglobin was 4.7 g/dl. Average stay was 19 days. CONCLUSIONS: In our center, HRA almost equally affects both genders and appears in older people with excessive anticoagulation and cough. The clinical presentation, increased diagnostic sensitivity of CT scan and predominance in the right abdominal involvement are similar to other series. Mortality and hospital stay are higher than described.


Assuntos
Hematoma , Doenças Musculares , Reto do Abdome , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hematoma/diagnóstico , Hematoma/terapia , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Musculares/diagnóstico , Doenças Musculares/terapia , Atenção Primária à Saúde , Estudos Retrospectivos
5.
An Med Interna ; 23(4): 166-72, 2006 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-16796409

RESUMO

OBJECTIVES: To analyse the characteristics of the hospitalized very elderly people (age equal or superior to 80 years) with hypertension (HT). PATIENTS AND METHODS: Prospective study including the patients with HT who need hospitalization in our medical institution. Data collected were: demographic, clinical parameters, factors of vascular risk, hygienic-dietetic strategies, pharmacological treatment, cause of hospitalization, and biochemical determinations. RESULTS: There were included 92 very elderly patients (71 women); they represent 14 % of total hospitalized people. Two third parts had not realized academic studies, being 60 % of rural origin. Almost the half (41 %) was diabetic, and 27 % had dyslipidemia. Overall 62 % had 4 or more factors of cardiovascular risk. The hospitalization was related to the HT in the half of the cases, and 61 % had already previously some cardiovascular event. The lifestyle modifications more frequent were: not to smoke (95 %), no alcohol (81 %), and diet without salt (75 %). Diuretics were the most frequent anti-hypertensive agent used. The global mortality was two times superior to the hypertensive population < 80 years in the same period. CONCLUSIONS: The very elderly hypertensive patients of our study are fundamentally women, of rural origin and without academic studies. The above mentioned hospitalization is attributable directly to the HT in the half of the cases. They are a population of high cardiovascular risk, with previous events cardiac and cerebral-vascular. They confess to realize frequently the hygienic-dietetic strategies recommended. The diuretics are the anti-hypertensive agents most used for the HT. Since it was of waiting for the mortality in this group it is high.


Assuntos
Hospitalização/estatística & dados numéricos , Hipertensão/epidemiologia , Idoso de 80 Anos ou mais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Hipertensão/prevenção & controle , Masculino , População Rural , Espanha/epidemiologia
6.
Minerva Med ; 96(6): 425-8, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16518305

RESUMO

This report describes a rare case of intra-abdominal liposarcoma in a 67-year-old woman. The patient presented at Internal Medicine Unit in May 2004, to study of thyroid pathology. The clinical examination was normal, except for the finding of an asymptomatic mass in the abdomen. The patient knew the existence of tumor since time ago, but she confesses to have only occasional discomfort. In the abdominal ultrasonography a solid mass with large cystic component was detected but relation with other organs was not clear. Computed tomography revealed the presence of a mass with solid and cystic components, in contact with small intestine in the left side of abdomen. A complete resection of tumor arising from mesentery of jejunum was performed successfully with end to end anastomosis. The gross specimen was lobulated and measured 8.5 x 7.5 cm. The histopathology analysis showed proliferating lipoblasts with irregular nuclei on a myxoid background, with plexiform vascular pattern, characteristics belongs to myxoid type liposarcoma. The patient is alive and well one year after removal of tumor. The uncommon site and the exceptional cystic morphology of tumor are discussed, and so it must be included the primary mesenteric liposarcoma in the differential diagnosis of intra-abdominal tumors with cystic large areas.


Assuntos
Neoplasias do Jejuno/patologia , Lipossarcoma Mixoide/patologia , Neoplasias Peritoneais/patologia , Idoso , Feminino , Humanos
7.
Parasitology ; 129 Suppl: S285-300, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15938516

RESUMO

The tick-borne intracellular pathogen Anaplasma marginale (Rickettsiales: Anaplasmataceae) develops persistent infections in cattle and tick hosts. While erythrocytes appear to be the only site of infection in cattle, A. marginale undergoes a complex developmental cycle in ticks and transmission occurs via salivary glands during feeding. Many geographic isolates occur that vary in genotype, antigenic composition, morphology and infectivity for ticks. In this chapter we review recent research on the host-vector-pathogen interactions of A. marginale. Major surface proteins (MSPs) play a crucial role in the interaction of A. marginale with host cells. The MSP1a protein, which is an adhesin for bovine erythrocytes and tick cells, is differentially regulated and affects infection and transmission of A. marginale by Dermacentor spp. ticks. MSP2 undergoes antigenic variation and selection in cattle and ticks, and contributes to the maintenance of persistent infections. Phylogenetic studies of A. marginale geographic isolates using msp4 and msp1alpha provide information about the biogeography and evolution of A. marginale: msp1alpha genotypes evolve under positive selection pressure. Isolates of A. marginale are maintained by independent transmission events and a mechanism of infection exclusion in cattle and ticks allows for only the infection of one isolate per animal. Prospects for development of control strategies by use of pathogen and tick-derived antigens are discussed. The A. marginale/vector/host studies described herein could serve as a model for research on other tick-borne rickettsiae.


Assuntos
Anaplasma marginale/fisiologia , Anaplasmose/microbiologia , Vetores Aracnídeos/microbiologia , Doenças dos Bovinos/microbiologia , Carrapatos/microbiologia , Anaplasma marginale/classificação , Anaplasmose/prevenção & controle , Anaplasmose/transmissão , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Doenças dos Bovinos/transmissão , Eritrócitos/microbiologia , Interações Hospedeiro-Parasita , Filogenia
8.
Int J Parasitol ; 31(14): 1705-14, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11730800

RESUMO

Anaplasma marginale, an ehrlichial pathogen of cattle and wild ruminants, is transmitted biologically by ticks. A developmental cycle of A. marginale occurs in a tick that begins in gut cells followed by infection of salivary glands, which are the site of transmission to cattle. Geographic isolates of A. marginale vary in their ability to be transmitted by ticks. In these experiments we studied transmission of two recent field isolates of A. marginale, an Oklahoma isolate from Wetumka, OK, and a Florida isolate from Okeechobee, FL, by two populations of Dermacentor variabilis males obtained from the same regions. The Florida and Oklahoma tick populations transmitted the Oklahoma isolate, while both tick populations failed to transmit the Florida isolate. Gut and salivary gland infections of A. marginale, as determined by quantitative PCR and microscopy, were detected in ticks exposed to the Oklahoma isolate, while these tissues were not infected in ticks exposed to the Florida isolate. An adhesion-recovery assay was used to study adhesion of the A. marginale major surface protein (MSP) 1a to gut cells from both tick populations and cultured tick cells. We demonstrated that recombinant Escherichia coli expressing Oklahoma MSP1a adhered to cultured and native D. variabilis gut cells, while recombinant E. coli expressing the Florida MSP1a were not adherent to either tick cell population. The MSP1a of the Florida isolate of A. marginale, therefore, was unable to mediate attachment to tick gut cells, thus inhibiting salivary gland infection and transmission to cattle. This is the first report of MSP1a being responsible for effecting infection and transmission of A. marginale by Dermacentor spp. ticks. The mechanism of tick infection and transmission of A. marginale is important in formulating control strategies and development of improved vaccines for anaplasmosis.


Assuntos
Anaplasma/crescimento & desenvolvimento , Anaplasmose/transmissão , Proteínas da Membrana Bacteriana Externa/fisiologia , Doenças dos Bovinos/transmissão , Dermacentor/microbiologia , Infestações por Carrapato/veterinária , Anaplasma/genética , Anaplasma/ultraestrutura , Anaplasmose/parasitologia , Animais , Aderência Bacteriana/genética , Proteínas da Membrana Bacteriana Externa/genética , Western Blotting/veterinária , Bovinos , Doenças dos Bovinos/parasitologia , DNA Bacteriano/genética , DNA Ribossômico/genética , Vetores de Doenças , Eletroforese em Gel de Poliacrilamida/veterinária , Escherichia coli/genética , Feminino , Florida , Masculino , Oklahoma , Reação em Cadeia da Polimerase/veterinária , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Glândulas Salivares/parasitologia , Infestações por Carrapato/microbiologia , Infestações por Carrapato/parasitologia
9.
Vet Parasitol ; 102(1-2): 151-61, 2001 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-11705661

RESUMO

Anaplasmosis is a hemolytic disease of cattle caused by the ehrlichial tick-borne pathogen Anaplasma marginale. Killed vaccines used for control of anaplasmosis in the US used antigen harvested from infected bovine erythrocytes which was often contaminated with bovine cells and other pathogens. In this study, we performed an initial cattle trial to test A. marginale harvested from tick cell culture as an immunogen for cattle. Eleven yearling Holstein cattle were immunized with the cell culture-derived A. marginale and 11 cattle were non-immunized contact controls. Each vaccine dose contained approximately 2 x 10(10) A. marginale in an oil-based adjuvant. Two immunizations were administered subcutaneously 4 weeks apart and the cattle were challenge-exposed 10 weeks after the second immunization with A. marginale infected blood. Maximum antibody levels as determined by an A. marginale specific competitive ELISA were observed 2 weeks after the last immunization. Antibody responses against major surface proteins (MSPs) 1a and 1beta1 were also characterized and immunized cattle demonstrated a preferential recognition for MSP1beta1. Cattle immunized with the cell culture-derived A. marginale had a significantly lower percent reduction in the packed cell volume (P<0.05) after challenge exposure as compared with the controls and did not display clinical anaplasmosis. The cell culture-derived A. marginale shows promise for use as antigen in development of a new killed vaccine for anaplasmosis.


Assuntos
Anaplasma/imunologia , Anaplasmose/prevenção & controle , Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas Bacterianas , Doenças dos Bovinos/prevenção & controle , Anaplasma/patogenicidade , Anaplasmose/imunologia , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/microbiologia , Linhagem Celular , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/veterinária , Injeções Subcutâneas/veterinária , Ixodes/embriologia , Vacinação/métodos , Vacinação/veterinária , Vacinas de Produtos Inativados
10.
BMC Biotechnol ; 1: 2, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11399206

RESUMO

BACKGROUND: The Gavac vaccine against the cattle tick Boophilus microplus has proven its efficacy in a large number of controlled and field experiments. However, this vaccine could be further improved by searching for new alternative adjuvants that would induce a stronger long-lasting immune response. We conducted several experiments to assay the adjuvant effect of fractions of the recombinant yeast Pichia pastoris in mouse and cattle models. In previous experiments, the combination of the yeast membrane with saponin was the most effective formulation in stimulating the humoral immune response in mice, eliciting a response higher than Montanide 888. The response was predominantly of the IgG1 isotype. Here, we evaluated the response in cattle and compared the results with that obtained in mice. RESULTS: Bm86 on the membrane of P. pastoris plus saponin produced high antibody titers in cattle, though the protection level against tick infestations was lower when compared to Gavac, probably due to a decrease in the IgG1/IgG2 ratio. The predictive value of the mouse model was studied through correlation analysis between the isotype levels in mice and the efficacy of formulations in cattle. Good correlation was established between the level of antibodies in mice and cattle, and between the amount of anti -Bm86 IgG1 in mice and the degree of protection in cattle. CONCLUSION: Mouse model have the potential to predict immunogenicity and efficacy of formulations in cattle. These results also support the use of the yeast expression system for recombinant vaccine formulations, enabling the prediction of more cost--effective formulations.


Assuntos
Adjuvantes Imunológicos , Antígenos/imunologia , Glicoproteínas de Membrana/imunologia , Pichia/imunologia , Proteínas Recombinantes , Carrapatos/imunologia , Vacinas/imunologia , Animais , Anticorpos/sangue , Anticorpos/imunologia , Bovinos , Modelos Animais de Doenças , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Larva/imunologia , Camundongos , Pichia/genética , Saponinas
11.
An Med Interna ; 18(2): 80-3, 2001 Feb.
Artigo em Espanhol | MEDLINE | ID: mdl-11322003

RESUMO

We report two cases of isolated abdominal wall actinomycosis and review 18 previously reported cases to further characterize the clinical findings and the therapeutic management of this syndrome. This diagnosis would be advocated in patients with a palpable abdominal mass of subacute appearance with a previous history of digestive medical illness, diabetes, abdominal surgery, or prolonged IUD use. In contrast with other actinomycosis locations, remarkable data were a more elevated mean age of patients; a female predominance; a prevalent location of mass in abdominal lower left quadrant; and a shorter duration of symptomatology before to diagnosis. The CT is the first choice for imaging study and percutaneous needle aspiration would be recommended for definite diagnosis. The long-term antibiotic therapy, with or without percutaneous drainage, is the first treatment choice because is very effective and made unnecessary a more invasive surgical management. The prognosis is excellent with adequated treatment.


Assuntos
Músculos Abdominais , Actinomicose/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
12.
Int J Parasitol ; 31(2): 145-53, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11239934

RESUMO

Anaplasma marginale is a tick-borne ehrlichial pathogen of cattle for which six major surface proteins (MSPs) have been described. The MSP1 complex, a heterodimer composed of MSP1a and MSP1b, was shown to induce a protective immune response in cattle and both proteins have been identified as putative adhesins for bovine erythrocytes. In this study the role of MSP1a and MSP1b as adhesins for bovine erythrocytes and tick cells was defined. msp1alpha and msp1beta1 genes from the Oklahoma isolate of A. marginale were cloned and expressed in Escherichia coli K-12 under the control of endogenous and tac promoters for both low and high level protein expression. Expression of the recombinant polypeptides was confirmed and localised on the surface of transformed E. coli. The adhesion properties of MSP1a and MSP1b were determined by allowing recombinant E. coli expressing these surface polypetides to react with bovine erythrocytes, Dermacentor variabilis gut cells and cultured tick cells derived from embryonic Ixodes scapularis. Adhesion of the recombinant E. coli to the three cell types was determined using recovery adhesion and microtiter haemagglutination assays, and by light and electron microscopy. MSP1a was shown by all methods tested to be an adhesin for bovine erythrocytes and both native and cultured tick cells. In contrast, recombinant E. coli expressing MSP1b adhered only to bovine erythrocytes and not to tick cells. When low expression vectors were used, single E. coli expressing MSP1a was seen adhered to individual tick cells while reaction of tick cells with the E. coli/MSP1a/high expression vector resulted in adhesion of multiple bacteria per cell. With electron microscopy, fusion of E. coli cell membranes expressing MSP1a or MSP1b with erythrocyte membranes was observed, as well as fusion of tick cell membranes with E. coli membranes expressing MSP1a. These studies demonstrated differential adhesion for MSP1a and MSP1b for which MSP1a is an A. marginale adhesin for both bovine erythrocytes and tick cells while MSP1b is an adhesin only for bovine erythrocytes. The role of the MSP1 complex, therefore, appears to vary among vertebrate and invertebrate hosts.


Assuntos
Adesinas Bacterianas/metabolismo , Anaplasma/fisiologia , Aderência Bacteriana , Eritrócitos/microbiologia , Carrapatos/microbiologia , Adesinas Bacterianas/genética , Anaplasma/crescimento & desenvolvimento , Anaplasmose/microbiologia , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Células Cultivadas , Dermacentor/microbiologia , Sistema Digestório/microbiologia , Eritrócitos/metabolismo , Escherichia coli/genética , Escherichia coli/fisiologia , Hemaglutinação , Ixodes/citologia , Ixodes/microbiologia , Microscopia Eletrônica , Proteínas Recombinantes/metabolismo , Carrapatos/citologia , Carrapatos/metabolismo
13.
Anim Health Res Rev ; 2(2): 163-73, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11831437

RESUMO

The major surface protein (MSP) 1a of the ehrlichial cattle pathogen Anaplasma marginale, encoded by the single-copy gene msp1alpha, has been shown to have a neutralization-sensitive epitope and to be an adhesin for bovine erythrocytes and tick cells. msp1alpha has been found to be a stable genetic marker for the identification of geographic isolates of A. marginale throughout development in acutely and persistently infected cattle and in ticks. The molecular weight of MSP1a varies among geographic isolates of A. marginale because of a varying number of tandemly repeated peptides of 28-29 amino acids. Variation in the sequence of the tandem repeats occurs within and among isolates, and may have resulted from evolutionary pressures exerted by ligand-receptor and host-parasite interactions. These repeated sequences include markers for tick transmissibility that may be important in the identification of ehrlichial pathogens because they may influence control strategies and the design of subunit vaccines.


Assuntos
Anaplasma/genética , Anaplasmose/microbiologia , Proteínas da Membrana Bacteriana Externa/genética , Doenças dos Bovinos/microbiologia , Sequências de Repetição em Tandem/genética , Sequência de Aminoácidos , Anaplasma/classificação , Anaplasmose/transmissão , Animais , Proteínas da Membrana Bacteriana Externa/química , Sequência de Bases , Bovinos , Marcadores Genéticos , Geografia , Dados de Sequência Molecular , Peso Molecular , Filogenia , Regiões Promotoras Genéticas/genética , Alinhamento de Sequência/veterinária , Doenças Transmitidas por Carrapatos/microbiologia , Estados Unidos
14.
Vet Parasitol ; 92(3): 209-22, 2000 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10962158

RESUMO

Boophilus spp. (Acari: Ixodidae) parasitize cattle and other farm and wild animals in tropical and subtropical regions of the world. Ticks belonging to the genus Boophilus have undergone evolutionary processes associated with habitat adaptation following biogeographical separation, resulting in strains with marked morphological differences. We have characterized at the molecular level B. microplus strains from Latin America and Australia, employing sequences derived from the bm86 coding region, an intron located within the bm86 gene, and DNA short tandem repeats (STR). A B. annulatus strain was employed for comparison. The results indicated that variation within the bm86 coding region is higher between B. microplus strains than between some B. microplus strains and B. annulatus. The sequence of the intron was not informative for phylogenetic analysis, varying among individuals of the same strain. Two STRs were identified in B. microplus (STRs BmM1 and BmM2) and one in B. annulatus (STR Ba1). Southern hybridization experiments with STRs BmM1 and BmM2 as a probe revealed the prevalence of dispersed moderately repeated DNA in the genome of B. microplus. The analysis of polymorphism at STR locus BmM1 evidenced differences within and between populations of B. microplus. These results support at the molecular level the existing differences between B. microplus strains and suggest tools to characterize these populations.


Assuntos
Ixodes/genética , Animais , Sequência de Bases , DNA/química , Variação Genética , Genoma , Ixodes/classificação , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência
15.
Vaccine ; 18(21): 2275-87, 2000 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-10717348

RESUMO

The recombinant Bm86-containing vaccine Gavac(TM) against the cattle tick Boophilus microplus has proved its efficacy in a number of experiments, especially when combined with acaricides in an integrated manner. However, tick isolates such as the Argentinean strain A, show low susceptibility to this vaccine. In this paper we report on the isolation of the Bm95 gene from the B. microplus strain A, which was cloned and expressed in the yeast Pichia pastoris producing a glycosylated and particulated recombinant protein. This new antigen was effective against different tick strains in a pen trial, including the B. microplus strain A, resistant to vaccination with Bm86. A Bm95-based vaccine was used to protect cattle against tick infestations under production conditions, lowering the number of ticks on vaccinated animals and, therefore, reducing the frequency of acaricide treatments. The Bm95 antigen from strain A was able to protect against infestations with Bm86-sensitive and Bm86-resistant tick strains, thus suggesting that Bm95 could be a more universal antigen to protect cattle against infestations by B. microplus strains from different geographical areas.


Assuntos
Antígenos/imunologia , Doenças dos Bovinos/prevenção & controle , Infestações por Carrapato/veterinária , Carrapatos/imunologia , Vacinas Sintéticas/imunologia , Animais , Formação de Anticorpos , Antígenos/genética , Sequência de Bases , Bovinos , Clonagem Molecular , Feminino , Lactação , Dados de Sequência Molecular , Pichia/genética , Proteínas Recombinantes/isolamento & purificação , Infestações por Carrapato/prevenção & controle , Vacinação
17.
Ann N Y Acad Sci ; 916: 617-21, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11193686

RESUMO

The control of tick infestations and the transmission of tick-borne diseases remain a challenge for the scientific community. Traditional control methods have been only partially successful. Recently, vaccination with recombinant Boophilus microplus gut antigens has been shown to control tick infestations. Our Bm86-containing vaccine formulation (Gavac) has been effective for the control of artificial infestations of B. annulatus, B. decoloratus, and chemically sensitive and resistant B. microplus strains from Australia, Africa, America, and Iran. Preliminary results with Hyalomma spp. and Rhipicephalus spp. suggest partial cross protection. In field trials, vaccination with Gavac controlled B. microplus and B. annulatus infestations and reduced the transmission of babesiosis, resulting in important savings for the cattle industry. Different degrees of susceptibility to the vaccination with Bm86 and sequence variations in the Bm86 locus have been reported. The Bm95 antigen was isolated from the Argentinean Bm86-resistant B. microplus strain A. A Bm95-based vaccine was used to protect cattle against tick infestations under production conditions with similar results to that obtained with Gavac. The Bm95 antigen from strain A was able to protect against infestations with Bm86-sensitive and Bm86-resistant tick strains, thus suggesting that Bm95 could be a more universal antigen in protecting cattle against infestations by B. microplus strains from different geographical areas. These results clearly demonstrate the advantage and possibilities for the immunological control of ticks.


Assuntos
Doenças dos Bovinos/imunologia , Ixodes/imunologia , Glicoproteínas de Membrana/imunologia , Proteínas Recombinantes , Infestações por Carrapato/veterinária , Vacinas/imunologia , Animais , Bovinos , Doenças dos Bovinos/prevenção & controle , Sistema Digestório/imunologia , Controle de Ácaros e Carrapatos/métodos , Infestações por Carrapato/imunologia , Infestações por Carrapato/prevenção & controle
18.
Genet Anal ; 15(3-5): 143-8, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10596754

RESUMO

The control of tick infestations and the transmission of tick-borne diseases remain a challenge for the cattle industry in tropical and subtropical areas of the world. Traditional control methods have been only partially successful and the parasites continue to result in significant losses for the cattle industry. Recently, vaccines containing the recombinant B. microplus gut antigen Bm86 have been developed. Our vaccine formulation (Gavac, Heber Biotec S.A., Havana, Cuba) has been registered and is commercially available in Cuba, Colombia, Dominican Republic, Brazil and Mexico. In controlled pen trials, Gavac has been effective for the control of artificial infestations of B. annulatus, B. decoloratus and chemical-sensitive and resistant B. microplus strains from Australia, Africa, America and Iran. In controlled field trials in Cuba, Brazil, Argentina and Mexico, Gavac has shown a 55-100% efficacy in the control of B. microplus infestations in grazing cattle 12-36 weeks after the first vaccination. Field trials under production conditions have been conducted in Cuba, Colombia, Brazil and Mexico in pure and cross-bred cattle herds. The application of Gavac has increased the time between acaricide treatments by an average of 32 /-21 days (P = 0.0005) resulting in important savings for the cattle industry. In Cuba, a cost-effectiveness analysis was conducted in more than 260000 animals. The cost-effectiveness analysis showed a 60% reduction in the number of acaricide treatments, together with the control of tick infestations and transmission of babesiosis, which resulted in savings of 23.4 dollars animal(-1) year (-1). These results clearly demonstrate the advantage of vaccination and support the application of Gavac for the control of Boophilus spp. infestations.


Assuntos
Vetores Aracnídeos/imunologia , Doenças dos Bovinos/prevenção & controle , Glicoproteínas de Membrana/imunologia , Proteínas Recombinantes , Controle de Ácaros e Carrapatos/métodos , Infestações por Carrapato/veterinária , Carrapatos/imunologia , Vacinação/veterinária , Vacinas Sintéticas/imunologia , Vacinas , Animais , Bovinos , Doenças dos Bovinos/economia , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/parasitologia , Análise Custo-Benefício , Feminino , América Latina , Ensaios Clínicos Controlados Aleatórios como Assunto/veterinária , Infestações por Carrapato/economia , Infestações por Carrapato/epidemiologia , Infestações por Carrapato/imunologia , Infestações por Carrapato/parasitologia , Infestações por Carrapato/prevenção & controle , Vacinação/economia , Vacinas Sintéticas/economia
20.
Exp Appl Acarol ; 23(11): 883-95, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10668863

RESUMO

Cattle tick infestations constitute a major problem for the cattle industry in tropical and subtropical regions of the world. Traditional control methods have been only partially successful, hampered by the selection of chemical-resistant tick populations. The Boophilus microplus Bm86 protein was isolated from tick gut epithelial cells and shown to induce a protective response against tick infestations in vaccinated cattle. Vaccine preparations including the recombinant Bm86 are used to control cattle tick infestations in the field as an alternative measure to reduce the losses produced by this ectoparasite. The principle for the immunological control of tick infestations relies on a polyclonal antibody response against the target antigen and, therefore, should be difficult to select for tick-resistant populations. However, sequence variations in the Bm86 locus, among other factors, could affect the effectiveness of Bm86-containing vaccines. In the present study we have addressed this issue, employing data obtained with B. microplus strains from Australia, Mexico, Cuba, Argentina and Venezuela. The results showed a tendency in the inverse correlation between the efficacy of the vaccination with Bm86 and the sequence variations in the Bm86 locus (R2 = 0.7). The mutation fixation index in the Bm86 locus was calculated and shown to be between 0.02 and 0.1 amino acids per year. Possible implications of these findings for the immunoprotection of cattle against tick infestations employing the Bm86 antigen are discussed.


Assuntos
Doenças dos Bovinos/imunologia , Variação Genética , Ixodes , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/imunologia , Proteínas Recombinantes , Infestações por Carrapato/veterinária , Vacinas Sintéticas , Vacinas , Sequência de Aminoácidos , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/prevenção & controle , Clonagem Molecular , Células Epiteliais/imunologia , Ixodes/genética , Ixodes/imunologia , Glicoproteínas de Membrana/química , Dados de Sequência Molecular , Infestações por Carrapato/imunologia , Infestações por Carrapato/prevenção & controle , Vacinação/veterinária
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