Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
1.
Ticks Tick Borne Dis ; 11(1): 101283, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31519420

RESUMEN

Tick-borne diseases (TBD) occur in many temperate countries and are economically important in most tropical and subtropical areas, affecting dairy and beef cattle, as well as small ruminants. Four major tick-borne diseases have been detected in eastern and southern Africa: East Coast fever (ECF) caused by Theileria parva, Theiler 1904, anaplasmosis caused by either Anaplasma marginale, Theiler 1910, Anaplasma centrale, Theiler 1911, or Anaplasma ovis, Bevan 1912, babesiosis caused by Babesia bovis, Babes 1988 and Babesia bigemina, Smith & Kilborne 1893, and heartwater caused by Ehrlichia ruminantium Cowdry 1925. A cross-sectional survey was undertaken to determine the antibody prevalence of these TBDs and to identify the risk factors for TBD infections in the Union of the Comoros. In 2016 and 2017, 903 individual animal serum samples were collected from 429 separate farms, where the farmers answered individual questionnaires. The antibody prevalence of anaplasmosis, babesiosis (B. bigemina) and heartwater was determined by enzyme-linked immunosorbent assays (ELISA) and the antibody prevalence of ECF was assessed using an immunofluorescence antibody test (IFAT). The relationship between TBD seropositivity and livestock-related variables was assessed by multivariate analyses with standard logistic regression models. The results showed that these four TBDs were present in the Union of the Comoros with a global antibody prevalence of 15% (95% CI [12.7%; 17.3%]) for anaplasmosis, 9.2% (95% CI [6.5%, 11.9%]) for B. bigemina babesiosis, 5.3% (95% CI [3.2%, 7.4%]) for ECF and 4.6% (95% CI [3.2%, 6%]) for heartwater. We compared these findings with the abundance and distribution of several tick species known to be TBD vectors and we found a significant correlation between Rhipicephalus appendiculatus and ECF, and between Amblyomma variegatum and heartwater. We also found that two major variables were significantly correlated with B. bigemina antibody prevalence ("island" and "breeding area"), four variables were significantly correlated with anaplasmosis antibody seroprevalence ("island", "number of cattle per farmer", "number of farmers per village" and "breeding area"), two were significantly correlated with ECF antibody prevalence ("number of farmers in village" and "presence of ticks"), and three were significantly correlated with heartwater ("island", "number of cattle per farmer" and "number of farmers in the village"). Our findings confirmed livestock exposure to the four targeted TBDs of major concern for livestock development. Consequently, raising farmers' awareness and setting up a period of quarantine should be considered a priority.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , Enfermedades de las Cabras/epidemiología , Enfermedades de las Ovejas/epidemiología , Enfermedades por Picaduras de Garrapatas/veterinaria , Animales , Anticuerpos Antibacterianos/análisis , Anticuerpos Antiprotozoarios/análisis , Bovinos , Enfermedades de los Bovinos/microbiología , Enfermedades de los Bovinos/parasitología , Comoras/epidemiología , Estudios Transversales , Ensayo de Inmunoadsorción Enzimática/veterinaria , Técnica del Anticuerpo Fluorescente Indirecta/veterinaria , Enfermedades de las Cabras/microbiología , Enfermedades de las Cabras/parasitología , Cabras , Prevalencia , Factores de Riesgo , Ovinos , Enfermedades de las Ovejas/microbiología , Enfermedades de las Ovejas/parasitología , Oveja Doméstica , Enfermedades por Picaduras de Garrapatas/epidemiología , Enfermedades por Picaduras de Garrapatas/microbiología , Enfermedades por Picaduras de Garrapatas/parasitología
2.
Trop Anim Health Prod ; 51(1): 99-107, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30014196

RESUMEN

East Coast fever (ECF), one of the most serious tick-borne diseases in sub-Saharan and eastern Africa, was introduced to the island of Grande Comore in 2002 through zebu import from Tanzania, resulting in at least a 10% loss of livestock. A participatory epidemiology initiative was launched in 2015 to gain a better understanding of ECF epidemiology. Thirty-six villages were investigated involving 36 focus group sessions and 120 individual questionnaires. Farmers' knowledge of ECF and of priority diseases affecting the country was assessed, and the impacts of ECF and other major diseases were compared by a scoring method. The results showed that 69.4% (95% CI [51.3, 87.5%]) of the farmers had good to very good knowledge of ECF. The most important cattle diseases on Grande Comore were considered to be East Coast fever, heartwater, babesiosis, and cutaneous diseases. About 58% of the farmers (95% CI [49.2, 66.8%]) use curative treatments when cattle were sick. Between January and September 2015, the ECF incidence was estimated at 18.5% (95% CI [15.5, 21.4%]), and 87.5% (95% CI [72.7, 100%]) of the cattle infected by ECF died. The ECF incidence estimated in our study was found to be less when compared to that observed in Tanzania even though the climatic conditions in the Union of the Comoros are suitable for the biological vector of ECF, the tick species Rhipicephalus appendiculatus. Access to chemical treatment and its effectiveness against ECF, as well as controlling borders and organizing quarantine, are discussed.


Asunto(s)
Participación de la Comunidad , Theileriosis/epidemiología , Enfermedades por Picaduras de Garrapatas/epidemiología , Animales , Vectores Arácnidos , Bovinos , Comoras/epidemiología , Humanos , Incidencia , Rhipicephalus , Tanzanía/epidemiología , Theileriosis/prevención & control , Enfermedades por Picaduras de Garrapatas/prevención & control
3.
Transbound Emerg Dis ; 63(4): 452-9, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25430822

RESUMEN

Late October 2012, a great number of deaths of unknown origin occurred in goat herds in the suburbs of Ngazidja, located in the Comoros archipelago. Few weeks later, laboratory testing requested by the animal health authorities resulted in the identification of peste des petits ruminants (PPR) infection. Notably, the Index case could be attributed to a sick goat imported from Tanzania. Viral isolation was successful from the lungs leading to the whole N nucleoprotein gene sequencing. Phylogenetic analysis revealed that the strain belongs to the lineage III which includes strains of eastern African origin. In addition, to evaluate the impact of PPR on the Comorian indigenous domesticated ruminant population, a cross-sectional PPR serological survey was conducted between April and July 2013. A low overall PPRV antibody prevalence 2.24% (95% CI [1.38; 3.08]) was detected with a Grande Comore prevalence of 3.34% (IC = [2.09; 4.63]) with a limited spread of the disease mainly due to farm practices such as limited contacts between farm animals and rapid slaughtering of sick animals.


Asunto(s)
Peste de los Pequeños Rumiantes/epidemiología , Animales , Anticuerpos Antivirales/sangre , Comoras/epidemiología , Estudios Transversales , Pulmón/virología , Virus de la Peste de los Pequeños Rumiantes/genética , Virus de la Peste de los Pequeños Rumiantes/inmunología , Filogenia
4.
Plant Dis ; 92(3): 485, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30769695

RESUMEN

Grapevine leafroll disease (GLD) has been recognized as one of the major constraints to the production of wine grapes in Washington State. At least nine distinct Grapevine leafroll-associated viruses (GLRaV-1 to -9) have been detected in grapevines showing GLD symptoms in grape-growing areas of several countries. Previous studies documented the presence of GLRaV-1, -2, and -3 in Washington State (3). We initiated a program to test grapevine cultivars with GLD symptoms for the occurrence of the other GLRaVs. Leaf samples were collected from individual grapevines of red-berried grapevine cultivars showing typical GLD symptoms and tested by single-tube reverse transcription (RT)-PCR. Of nearly 300 samples from 13 cultivars in 19 vineyards, 14 samples from 5 cultivars (Cabernet Sauvignon, Merlot, Pinot Noir, Mourvedre, and Lagrein) in different vineyards tested positive for GLRaV-9 using primers LR9 F/F (5'-CGG CAT AAG AAA AGA TGG CAC-3') and LR9 R/R (5'-TCA TTC ACC ACT GCT TGA AC-3'), specific for the HSP-70h gene of GLRaV-9 (1). To confirm the identity of the RT-PCR products, the 393-bp amplicons obtained from each of these five cultivars were cloned individually into the pCR2.1 plasmid (Invitrogen Corp., Carlsbad, CA). Two independent clones per amplicon were sequenced from both orientations. Pairwise comparisons of these sequences (GenBank Accession Nos. EF101737, EF101738, EF101739, EF101740, and EU252530) with corresponding sequences of other GLRaVs in GenBank showed 94 to 100 and 96 to 100% identity at the nucleotide and amino acid level, respectively, with the sequence of HSP-70h gene of GLRaV-9 (GenBank Accession No. AY297819). Antiserum specific to GLRaV-9 was not accessible, therefore, an additional 540-nucleotide fragment specific to the coat protein (CP) gene of GLRaV-9 was amplified from cv. Lagrein using primers LR9-CP-F (5' TAC CGT CGA CAC TTT CGA AGC ACT 3') and LR9-CP-R (5' TGA GGC GTC GTA ACC GAA CAA TCT 3'). PCR amplified fragments were cloned and sequenced. A comparison of this sequence (GenBank Accession No. EU251512) with corresponding nucleotide sequences of other GLRaVs in GenBank showed 96% identity with CP of GLRaV-9 (GenBank Accession No. AY297819), further confirming the presence of GLRaV-9. Previously, GLRaV-9 was reported in grapevines in California (1), Tunisia (2), and Western Australia (4). To our knowledge, our results are the first evidence for the occurrence of GLRaV-9 in Washington State vineyards. Results from our study and previous reports (1,2,4) indicate the wide distribution of GLRaV-9 in several Vitis vinifera cultivars. The economic impact of GLRaV-9 on wine grape cultivars, however, remains to be determined. References: (1) R. Alkowni et al. J. Plant Pathol. 86:123, 2004. (2) N. Mahfoudhi et al. Plant Dis. 91:1359, 2007. (3) R. R. Martin et al. Plant Dis. 89:763, 2005. (4) B. K. Peake et al. Aust. Plant Pathol. 33:445, 2004.

5.
Plant Dis ; 90(11): 1461, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30780926

RESUMEN

Washington State is the largest producer of juice grapes (Vitis labruscana 'Concord' and Vitis labrusca 'Niagara') and ranks second in wine grape production in the United States. Grapevine leafroll disease (GLD) is the most wide spread and economically significant virus disease in wine grapes in the state. Previous studies (2) have shown that Grapevine leafroll associated virus-3 (GLRaV-3) is the predominant virus associated with GLD. However, little is known about the incidence and economic impact of GLD on juice and table grapes. Because typical GLD symptoms may not be obvious among these cultivars, the prevalence and economic impact of GLD in Concord and Niagara, the most widely planted cultivars in Washington State, has received little attention from the grape and nursery industries. During the 2005 growing season, 32 samples from three vineyards and one nursery of 'Concord' and three samples from one nursery of 'Niagara' were collected randomly. Petiole extracts were tested by single-tube reverse transcription-polymerase chain reaction (RT-PCR; 3) with primers LC 1 (5'-CGC TAG GGC TGT GGA AGT ATT-3') and LC 2 (5'-GTT GTC CCG GGT ACC AGA TAT-3'), specific for the heat shock protein 70 homologue (Hsp70h gene) of GLRaV-3 (GenBank Accession No. AF037268). One 'Niagara' nursery sample and eleven 'Concord' samples from the three vineyards tested positive for GLRaV-3, producing a single band of the expected size of 546 bp. The 'Niagara' and six of the 'Concord' RT-PCR products were cloned in pCR2.1 (Invitrogen Corp, Carlsbad, CA) and the sequences (GenBank Accession Nos. DQ780885, DQ780886, DQ780887, DQ780888, DQ780889, DQ780890, and DQ780891) compared with the respective sequence of a New York isolate of GLRaV-3 (GenBank Accession No. AF037268). The analysis revealed that GLRaV-3 isolates from 'Concord' and 'Niagara' share nucleotide identities of 94 to 98% and amino acid identities and similarities of 97 to 98% with the Hsp70h gene homologue of the New York isolate of GLRaV-3. Additional testing by double-antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) using antibodies specific to GLRaV-3 (BIOREBA AG, Reinach, Switzerland) further confirmed these results in the 'Niagara' and two of the 'Concord' isolates. GLRaV-3 has previously been reported in labrusca cvs. Concord and Niagara in western New York (4) and Canada (1), but to our knowledge, this is the first report of GLRaV-3 in American grapevine species in the Pacific Northwest. Because wine and juice grapes are widely grown in proximity to each other in Washington State and grape mealybug (Pseudococcus maritimus), the putative vector of GLRaV-3, is present in the state vineyards, further studies will focus on the role of American grapevine species in the epidemiology of GLD. References: (1) D. J. MacKenzie et al. Plant Dis. 80:955, 1996. (2) R. R. Martin et al. Plant Dis. 89:763, 2005. (3) A. Rowhani et al. ICGV, Extended Abstracts, 13:148, 2000. (4) W. F. Wilcox et al. Plant Dis. 82:1062, 1998.

6.
J Bacteriol ; 183(21): 6454-65, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11591691

RESUMEN

Two seven-gene phenazine biosynthetic loci were cloned from Pseudomonas aeruginosa PAO1. The operons, designated phzA1B1C1D1E1F1G1 and phzA2B2C2D2E2F2G2, are homologous to previously studied phenazine biosynthetic operons from Pseudomonas fluorescens and Pseudomonas aureofaciens. Functional studies of phenazine-nonproducing strains of fluorescent pseudomonads indicated that each of the biosynthetic operons from P. aeruginosa is sufficient for production of a single compound, phenazine-1-carboxylic acid (PCA). Subsequent conversion of PCA to pyocyanin is mediated in P. aeruginosa by two novel phenazine-modifying genes, phzM and phzS, which encode putative phenazine-specific methyltransferase and flavin-containing monooxygenase, respectively. Expression of phzS alone in Escherichia coli or in enzymes, pyocyanin-nonproducing P. fluorescens resulted in conversion of PCA to 1-hydroxyphenazine. P. aeruginosa with insertionally inactivated phzM or phzS developed pyocyanin-deficient phenotypes. A third phenazine-modifying gene, phzH, which has a homologue in Pseudomonas chlororaphis, also was identified and was shown to control synthesis of phenazine-1-carboxamide from PCA in P. aeruginosa PAO1. Our results suggest that there is a complex pyocyanin biosynthetic pathway in P. aeruginosa consisting of two core loci responsible for synthesis of PCA and three additional genes encoding unique enzymes involved in the conversion of PCA to pyocyanin, 1-hydroxyphenazine, and phenazine-1-carboxamide.


Asunto(s)
Proteínas Bacterianas/fisiología , Operón , Fenazinas/metabolismo , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , Piocianina/biosíntesis , Proteínas Bacterianas/genética , Clonación Molecular , Metiltransferasas/genética , Metiltransferasas/fisiología , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/fisiología , Modelos Químicos , Datos de Secuencia Molecular , Oxigenasas/genética
7.
Arch Inst Cardiol Mex ; 68(5): 383-90, 1998.
Artículo en Español | MEDLINE | ID: mdl-10365234

RESUMEN

Direct myocardial revascularization techniques has earned great acceptance in the treatment of ischemic coronary syndromes in the past two decades. Almost since its beginnings the procedure was done with the aid of extracorporeal circulation, since the technical accessibility with cardiac standstill further helped to evolve the procedure. As years went by, complications due to the use of the pump became evident, such as microembolism, bleeding disorders, and others. Besides this, there is a special group of patients, those with high surgical risk, with preexisting pulmonary, hepatic or cerebral disease, who benefit a great deal when bypass grafting procedure is done without the pump. In this article we delineate the indications, contraindications, and the procedure itself based in our personal experience, reporting our first five patients with this technique.


Asunto(s)
Puente de Arteria Coronaria , Revascularización Miocárdica , Anciano , Contraindicaciones , Puente de Arteria Coronaria/efectos adversos , Circulación Extracorporea/efectos adversos , Humanos , Revascularización Miocárdica/efectos adversos , Factores de Riesgo
8.
Science ; 279(5359): 2060-1, 1998 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-17742319

RESUMEN

No more than 5% of the land area worldwide is being set aside for the protection of nature, and there is little evidence that much tropical biodiversity will survive outside of well-managed reserves. Many international development and conservation organizations recommend that at least 10% of territory be protected, though ecologists generally concur that at least 50% of all species will soon be lost if 90% of the habitat is seriously disrupted. Current policies, therefore, are a prescription for a massive loss of biodiversity.

11.
Science ; 253(5021): 744-50, 1991 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-17835488
12.
Artículo en Francés | MEDLINE | ID: mdl-3351207

RESUMEN

830 couples who had asked for Artificial Insemination by Donor (AID) were questioned using separate questionnaires for the husband and for the wife. The questions were directed to the reactions that followed in succession to discovery of the sterility, the psychological conditions that led to choosing AID, their attitude as far as secrecy was concerned and finally their contribution to finding donors of sperm. Overall the husband-wife replies corresponded to one another. Frequently the reaction to the news that the man is sterile is a depressive one and to a lesser degree followed by troubles in sexual performance. The choice of AID is usually a decision of both members of the couple. Most couples express themselves as hesitant about adoption. Most of them said that secrecy about the procedure was an essential condition. It appears that, above all, male sterility had to be hidden from the circle in which they associated and from the child. It is this position as far as secrecy is concerned that makes it difficult for the couples to help in recruiting sperm donors.


Asunto(s)
Actitud , Inseminación Artificial Heteróloga/psicología , Inseminación Artificial/psicología , Femenino , Humanos , Infertilidad/psicología , Infertilidad Masculina/psicología , Masculino , Encuestas y Cuestionarios , Revelación de la Verdad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...