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1.
Behav Neurol ; 2024: 4504858, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38566972

RESUMEN

Obsessive-compulsive disorder (OCD) is a disabling disease characterized by distressing obsessions and repetitive compulsions. The etiology of OCD is poorly known, and mouse modeling allows to clarify the genetic and neurochemical basis of this disorder and to investigate potential treatments. This study evaluates the impact of the 5-HT1B agonist RU24969 on the induction of OCD-like behaviours in female BALB/c mice (n = 30), distributed across five groups receiving varying doses of RU24969. Behavioural assessments, including marble test, tail suspension test, sucrose preference test, forced swim test, and nestlet shredding test, were conducted. Gene expression and protein quantitation of Gabra1 and serotonin transporter in mouse brain were also performed. Marble-burying behaviour increased significantly at high doses of RU24969 (15-20 mg/kg). The forced swimming test consistently showed elevated values at the same high concentrations, compared to the control. Altered reward-seeking behaviour was indicated by the sucrose preference test, notably at 15 and 20 mg/kg doses of RU24969. Nestlet shredding results did not show statistical significance among the tested animal groups. Gene expression analysis revealed reduced Gabra1 expression with increasing doses of RU, while serotonin transporter was not related to varying doses of RU24969. Western blotting corroborated these trends. The results underscore complex interactions between the serotonin system, GABAergic signaling, and OCD-relevant behaviours and suggest the use of intraperitoneal injection of 15 mg/kg of RU24969 to induce OCD-like behaviour in BALB/c mouse models.


Asunto(s)
Trastorno Obsesivo Compulsivo , Femenino , Ratones , Animales , Ratones Endogámicos BALB C , Trastorno Obsesivo Compulsivo/genética , Agonistas del Receptor de Serotonina 5-HT1/farmacología , Carbonato de Calcio , Sacarosa
2.
Int J Microbiol ; 2023: 8811675, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37303775

RESUMEN

The present study was undertaken to determine the antimicrobial resistance patterns and plasmid fingerprints of commensal Escherichia coli isolated from Lebanese broiler chickens. To that end, a total of 30 E. coli isolates were collected from 15 semi-open broiler farms from North Lebanon and Bekaa Valley. Results showed that all the isolates were resistant to at least nine out of 18 evaluated antimicrobial agents. The best-performing antibiotic families were Carbapenems (Imipenem) and Quinolones (Ciprofloxacin and Norfloxacin) to which only 0.0 and 8.3% of the isolates were resistant, respectively. Fifteen various plasmid profiles were depicted, and all the isolates were found to possess one or multiple plasmids. The plasmid sizes varied from 1.2 to 21.0 kbp, and the most commonly detected plasmid had a size of 5.7 kbp (23.3% of the isolates). There was no significant association between the number of plasmids per isolate and resistance to a particular drug. Nevertheless, the presence of specific plasmids, namely, the 2.2 or 7.7 kbp sized ones, was strongly correlated to Quinolones or Trimethoprim resistance, respectively. Both the 7.7 and 6.8 kbp plasmids showed mild correlation to Amikacin resistance, and the 5.7 kbp plasmid was mildly correlated to Piperacillin-Tazobactam resistance. Our findings highlight the need to revise the list of antimicrobials currently used in Lebanese poultry and associate the presence of specific plasmids to antimicrobial resistance patterns in E. coli isolates. The revealed plasmid profiles could also serve any future epidemiological investigation of poultry disease outbreaks in the country.

3.
Ann Parasitol ; 68(2): 227-239, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35809400

RESUMEN

This study documents the diversity of intestinal parasites in the eastern broad-toothed field mouse (Apodemus mystacinus) along the altitudinal gradient of Ibrahim River in Mount Lebanon during the spring and autumn of 2017. A total of 190 A. mystacinus were trapped in seventeen sites (6 riparian, 11 non-riparian) and examined for intestinal parasites. Eight intestinal parasites were identified including Heligmosomoides polygyrus, Trichuris muris, Syphacia frederici, Protospirura muris, and Aspiculuris tetraptera (nematodes), Hymenolepis diminuta (cestode), Brachylaima spp. (trematode), and Eimeria alorani (coccidian). Most of the trapped mice (85%) were infected with intestinal parasites and 38.84% showed concurrent infection with at least two parasitic species. The season had a significant effect on mice infection with Syphacia frederici, and mice are most likely to have infection with this nematode in spring season. The vegetation zone had a significant overall impact on mice infection with the nematodes Heligmosomoides polygyrus and Trichuris muris while gender did not influence significantly mouse infection with intestinal parasites. This is the first study that has been carried out to identify the intestinal parasite community in A. mystacinus of Ibrahim River region. The findings pave the way for future studies on intestinal parasites in rodents and the environmental variations affecting their dynamics.


Asunto(s)
Parasitosis Intestinales , Nematodos , Parásitos , Trematodos , Animales , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Parasitosis Intestinales/veterinaria , Líbano/epidemiología , Ratones , Murinae/parasitología , Ríos
4.
Ann Parasitol ; 68(3): 595-603, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36617398

RESUMEN

This study aims at the identification of endo- and ectoparasites in broiler farms while assessing their prevalence in semi-open and closed rearing systems in Lebanon. Seventeen semi-open and six closed broiler farms were investigated in various Lebanese provinces between March and September 2020 and 2021. Intestinal and composite litter samples were collected and observed for morphological identification of prevalent parasites. Results notably revealed the prevalence of mites in all of the surveyed farms. Moreover, mixed mite-helminth infestation was recorded in 100% of the semi-open farms and 50% of the closed ones. The northern fowl mite Ornithonyssus sylviarum was the predominant chicken parasitic mite in both systems. The poultry red mite Dermanyssus gallinae, was present in 6% of the semi-open farms and was not detected in closed farms. The mammalian itching mite Sarcoptes scabiei and the grain mite Acarus siro were also identified and had similar prevalence pattern as the red poultry mite. Eggs and/or larvae stages of one parasitic helminth species, Ascaridia galli, were detected in half of the semi-open and closed farms while adult worms were not present. This study documents for the first time the prevalence of specific endo- and ectoparasites in Lebanese broiler farms, reflecting managerial problems and poor biosecurity practices. Nevertheless, the identification of specific parasites in this work paves the way towards implementing proper control methods against these overlooked, yet devastating, organisms.


Asunto(s)
Helmintos , Infestaciones por Ácaros , Ácaros , Enfermedades de las Aves de Corral , Animales , Granjas , Pollos/parasitología , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/parasitología , Infestaciones por Ácaros/epidemiología , Infestaciones por Ácaros/veterinaria , Infestaciones por Ácaros/parasitología , Mamíferos
5.
Germs ; 9(1): 35-42, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31119115

RESUMEN

As a novel coronavirus first reported by Saudi Arabia in 2012, the Middle East respiratory syndrome coronavirus (MERS-CoV) is responsible for an acute human respiratory syndrome. The virus, of 2C beta-CoV lineage, expresses the dipeptidyl peptidase 4 (DPP4) receptor and is densely endemic in dromedary camels of East Africa and the Arabian Peninsula. MERS-CoV is zoonotic but human-to-human transmission is also possible. Surveillance and phylogenetic researches indicate MERS-CoV to be closely associated with bats' coronaviruses, suggesting bats as reservoirs, although unconfirmed. With no vaccine currently available for MERS-CoV nor approved prophylactics, its global spread to over 25 countries with high fatalities highlights its role as ongoing public health threat. An articulated action plan ought to be taken, preferably from a One Health perspective, for appropriately advanced countermeasures against MERS-CoV.

8.
Vet Ital ; 51(3): 217-24, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26455375

RESUMEN

The present study has two aims: to optimize the antiviral activity of oseltamivir in chicken embryos against an avian influenza-H9N2 strain (P0) and to apply the optimized protocol for studying the drug susceptibility of 4 H9N2 mutants (M1, M2, M3, and M4). As for the first aim, oseltamivir antiviral activity was monitored upon its delivery into 9-day-old chicken embryo at a concentration of 0.27 mg/100 µl, against 7 doses of the P0 strain, ranging between 1.2 x 10(-5) and 2.0 Hemagglutination (HA) units. Oseltamivir showed its highest efficacy in reduction of viral propagation (95% reduction in HA titer) (P 〈0.05), when the inoculum level contained a minimum HA units of 1.2 x 10(-5). For the second aim of this study, the application of the 1.2 x 10-(5) HA units of the virus in inocula for the evaluation of oseltamivir-antiviral effect against the 4 H9N2 mutants revealed an emergence of a resistant mutant (M1), associated with 2 adjacent point mutations in its neuraminidase (N) amino acid (aa) sequence at positions 46 and 47. The other 3 mutants maintained a variable sensitivity to oseltamivir, resulting in the following reduction in HA titers: M2 (82.9%), M3 (61.5%), and M4 (100.0%). How the point mutations of the neuraminidase sequences affected the susceptibility of H9N2 virus to oseltamivir is still to be determined and deserve further investigations.


Asunto(s)
Antivirales/farmacología , Subtipo H9N2 del Virus de la Influenza A/efectos de los fármacos , Subtipo H9N2 del Virus de la Influenza A/genética , Neuraminidasa/genética , Oseltamivir/farmacología , Mutación Puntual , Animales , Antivirales/uso terapéutico , Aves , Embrión de Pollo , Subtipo H9N2 del Virus de la Influenza A/enzimología , Gripe Aviar/tratamiento farmacológico , Oseltamivir/uso terapéutico
9.
Vaccine ; 33(19): 2228-2231, 2015 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-25820070

RESUMEN

The aim of this study was to evaluate an experimental Salmonella Enteritidis (SE) bacterin and an indirect ELISA system to assess quantitatively the acquired immunity in Awassi ewes to the vaccine and/or Echinacea purpurea (EP) dried roots. Four treatments of the ewes were included in the experimental design, with 6 ewes/treatment. The first treatment (T1) had the controls that were non-vaccinated and non-treated with EP. The T2 ewes were only treated with EP. The T3 and T4 ewes were vaccinated at D1 (initiation of trial) and D10, while the T4 ewes were additionally administered the EP dried roots. Blood was collected from the jugular vein of all ewes at D1, D10, D21 and D45. The construction of the vaccine and the ELISA are detailed within the manuscript. The ELISA was able to detect quantitatively the significant acquired primary and secondary immunity to the vaccine in T3 and T4 ewes, compared to their low level of background immunities at initiation of the experiment (p<0.05). In addition, the ELISA detected the absence of seroconversion at all blood sampling times (p>0.05) in T1 control ewes, and in the T2 ewes that were given only the (EP) (p>0.05). Moreover, the ELISA was able to uncover the significant seroconversion of secondary immune response in T4 ewes at D21 compared to that at D10 (p<0.05), and the absence of significant seroconversion of secondary response in T3 ewes. This is the first work in literature that reports the need to supplement the vaccination by the experimental SE bacterin with daily oral intake of 250mg of EP-dried roots, effective the first vaccination day and up to 21 days, for obtaining a statistically significant seroconversion.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Dieta/métodos , Echinacea , Salmonelosis Animal/prevención & control , Vacunas contra la Salmonella/inmunología , Salmonella enteritidis/inmunología , Enfermedades de las Ovejas/prevención & control , Administración Oral , Animales , Anticuerpos Antibacterianos/sangre , Ensayo de Inmunoadsorción Enzimática/métodos , Inyecciones Subcutáneas , Vacunas contra la Salmonella/administración & dosificación , Ovinos
11.
J Infect Dev Ctries ; 8(10): 1344-9, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-25313614

RESUMEN

INTRODUCTION: The role of Origanum ehrenberjii against bacteria that cause enteric diseases is well known. Salmonella and Enterococcus cause high rates of enteric infections around the world. The aim of this study was to extract essential oils from cultivated and naturally growing O. ehrenberjii, compare the chemical profiles of the extracts and estimate their antimicrobial efficacy against enteric pathogens. METHODOLOGY: Sixteen compounds were recovered consistently from essential oils extracted from O. ehrenberjii of wild and cultivated origin. The chemical profiles were determined using GC-MS. Safety of the essential oils was determined by observing mortality of chicks after intramuscular administration of the oils. The antimicrobial efficacy of the oils against the enteric pathogens was determined by the Kirby-Bauer Single Disk Diffusion assay. RESULTS: The levels of thymol, carvacrol, para cymene and γ-terpinene were significantly different in the two oils. A significant difference in in vitro antimicrobial activity of the two oils against Salmonella enterica serovar Typhimurium was observed. Intramuscular administration of the two oils in one day-old chicks resulted in significant differences in mortality of 60% vs. 5% (p < 0.05) for wild and cultivated herbs respectively, reflecting the higher safety of the cultivated herb due to the differences in the levels of certain active ingredients. CONCLUSIONS: The chemical profile of essential oil of wild vs. cultivated O. ehrenberjii differ significantly at compound level, suggesting the reason for their significant difference in efficacy against Salmonella enterica serovar Typhimurium, and also significant differences in the toxicity of the two oils.


Asunto(s)
Antibacterianos/farmacología , Enterococcus faecalis/efectos de los fármacos , Aceites Volátiles/farmacología , Origanum/química , Salmonella typhimurium/efectos de los fármacos , Animales , Antibacterianos/efectos adversos , Antibacterianos/análisis , Antibacterianos/aislamiento & purificación , Pollos , Cromatografía de Gases y Espectrometría de Masas , Inyecciones Intramusculares , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/efectos adversos , Aceites Volátiles/análisis , Aceites Volátiles/aislamiento & purificación , Análisis de Supervivencia
12.
J Infect Dev Ctries ; 8(5): 570-80, 2014 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-24820460

RESUMEN

INTRODUCTION: Avian influenza viruses of the H9N2 subtype have been reported to cause human infections. This study demonstrates the impact of nasal viral passaging of avian H9N2 in hamsters on its cross species-pathogenic adaptability and variability of amino acid sequences of the hemagglutinin (HA) and neuraminidase (NA) stalk. METHODOLOGY: Three intranasal passagings of avian H9N2 in hamsters P1, P2, and P3 were accomplished. Morbidity signs and lesions were observed three days post viral inoculation. The HA test was used for presumptive detection of H9N2 virus in the trachea and lungs of the hamsters challenged with the differently passaged viruses. Different primers were used for PCR amplification of the HA1 and NA stalk regions of the differently passaged H9N2 viruses, followed by sequence alignment. RESULTS: The morbidity signs indicated low pathogenicity of the differently passaged H9N2 viruses in hamsters. The frequency of gross and microscopic lesions in the tracheas and lungs were insignificantly different among hamsters challenged with the differently passaged H9N2 viruses (p > 0.05). There was 100% similarity in the amino acid sequence of the HA gene of most passaged viruses. The amino acid sequence of the neuraminidase in the third passaged H9N2 virus recovered from lungs showed a R46P mutation that might have a role in the pathogenic adaptability of P3 viruses in hamsters' lungs. CONCLUSIONS: The apparent adaptation of avian H9N2 virus to mammalian cells is in agreement with the World Health Organization's alertness for a possible public health threat by this adaptable virus.


Asunto(s)
Inestabilidad Genómica , Subtipo H9N2 del Virus de la Influenza A/crecimiento & desarrollo , Infecciones por Orthomyxoviridae/patología , Infecciones por Orthomyxoviridae/virología , Pase Seriado , Adaptación Biológica , Animales , Cricetinae , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Subtipo H9N2 del Virus de la Influenza A/genética , Subtipo H9N2 del Virus de la Influenza A/patogenicidad , Pulmón/virología , Neuraminidasa/genética , Análisis de Secuencia de ADN , Tráquea/virología , Proteínas Virales/genética , Virulencia
13.
Artículo en Inglés | MEDLINE | ID: mdl-23286237

RESUMEN

This mini review targets the inclusion of recent selected citations, between the year 2006 and 2012, that implement the qRT-rtPCR technology in their experimental designs, targeting the uncovering of the mechanism of food allergy. In addition, this same technology was implemented in specific experimental designs, aiming at finding novel nutritional, herbal medicine, and tolerance interventions against food allergy. The approach of using qRT-rtPCR technology helped in studying the dynamics of transcription of cytokines and chemokines in intestinal dendritic cells of the experimental animals during the allergic reaction to food. The suppression of transcription of specific cytokines or chemokines by nutritional, herbal medicine, and tolerance interventions was instrumental in the search for finding novel remedies for this health condition, that was traditionally managed by avoidance of offending foods in the diet.


Asunto(s)
Quimiocinas/metabolismo , Citocinas/metabolismo , Hipersensibilidad a los Alimentos/inmunología , Hipersensibilidad a los Alimentos/terapia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Animales , Quimiocinas/genética , Citocinas/genética , Células Dendríticas/metabolismo , Dieta , Hipersensibilidad a los Alimentos/fisiopatología , Humanos , Tolerancia Inmunológica , Ratones , Ratones Endogámicos BALB C
14.
Pathog Glob Health ; 106(6): 352-7, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23182140

RESUMEN

The objective of this work is to compare the phenotypic and virulence genes characteristics in human and chicken isolates of Proteus mirabilis. The bacterial examination of 50 livers of individual broilers, marketed by four major outlets, revealed a high recovery of P. mirabilis (66%), and a low recovery frequency of Salmonella spp. (4%), Serratia odorifera (2%), Citrobacter brakii (2%), and Providencia stuartii (2%). The phenotypic biochemical characterization of the recovered 33 chicken isolates of P. mirabilis were compared to 30 human isolates (23 urinary and six respiratory isolates). The comparison revealed significant differences in the presence of gelatinase enzyme (100% presence in chicken isolates versus 91.3 and 83.3% presence in human urinary and respiratory isolates, respectively, P,0.05). The H(2)S production occurred in 100% of chicken isolates versus 95.6 and 66.7% presence in human urinary and respiratory isolates, respectively, P,0.05). The other 17 biochemical characteristics did not differ significantly among the three groups of isolates (P.0.05). Two virulence genes, the mrpA and FliL, were having a typical 100% presence in randomly selected isolates of P. mirabilis recovered from chicken livers (N510) versus isolates recovered from urinary (N55) and respiratory specimens of humans (N55) (P.0.05). The average percentage similarity of mrpA gene nucleotide sequence of poultry isolates to human urinary and respiratory isolates was 93.2 and 97.5-%, respectively. The high similarity in phenotypic characteristics, associated with typical frequency of presence of two virulence genes, and high similarity in sequences of mrpA gene among poultry versus human P. mirabilis isolates justifies future investigations targeting the evaluation of adaptable pathogenicity of avian Proteus mirabilis isolates to mammalian hosts.


Asunto(s)
Enfermedades de las Aves de Corral/microbiología , Infecciones por Proteus/microbiología , Infecciones por Proteus/veterinaria , Proteus mirabilis/aislamiento & purificación , Proteus mirabilis/patogenicidad , Factores de Virulencia/genética , Animales , Proteínas Bacterianas/genética , Técnicas de Tipificación Bacteriana , Pollos , Gelatinasas/metabolismo , Humanos , Sulfuro de Hidrógeno/metabolismo , Proteínas de la Membrana/genética , Reacción en Cadena de la Polimerasa , Proteus mirabilis/genética
15.
Trop Anim Health Prod ; 44(7): 1513-9, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22350811

RESUMEN

The purpose of this research is to optimize quantitatively the amplification of specific sperm genes in reference genomically characterized Saanen goat and to evaluate the standardized protocols applicability on sperms of uncharacterized genome of rural goats reared under subtropical environment for inclusion in future selection programs. The optimization of the protocols in Saanen sperms included three production genes (growth hormone (GH) exons 2, 3, and 4, αS1-casein (CSN1S1), and α-lactalbumin) and two health genes (MHC class II DRB and prion (PrP)). The optimization was based on varying the primers concentrations and the inclusion of a PCR cosolvent (Triton X). The impact of the studied variables on statistically significant increase in the yield of amplicons was noticed in four out of five (80%) optimized protocols, namely in those related to GH, CSN1S1, α-lactalbumin, and PrP genes (P < 0.05). There was no significant difference in the yield of amplicons related to MHC class II DRB gene, regardless of the variables used (P > 0.05). The applicability of the optimized protocols of Saanen sperm genes on amplification of uncharacterized rural goat sperms revealed a 100% success in tested individuals for amplification of GH, CSN1S1, α-lactalbumin, and MHC class II DRB genes and a 75% success for the PrP gene. The significant success in applicability of the Saanen quantitatively optimized protocols to other uncharacterized genome of rural goats allows for their inclusion in future selection, targeting the sustainability of this farming system in a subtropical environment and the improvement of the farmers livelihood.


Asunto(s)
Cabras/genética , Reacción en Cadena de la Polimerasa/métodos , Análisis de Secuencia de ADN/métodos , Análisis de Varianza , Animales , Masculino , Reacción en Cadena de la Polimerasa/veterinaria , Polimorfismo Genético , Espermatozoides/metabolismo , Clima Tropical
16.
Trop Anim Health Prod ; 44(1): 87-93, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21720787

RESUMEN

Three objectives were included in this research work. The first objective compared different immune components in healthy mature males, mature females, and female kids of local and imported Saanen goats, reared under a sub-tropical environment. The significantly differing immune components were the blood monocyte percent, blood CD8 count, and the total white blood cell count. The second objective compared the performance of Saanen versus local does. The means of the milk yield and prolificacy of the imported Saanen does were significantly higher than those of the local does (p<0.05). The third objective compared the immune responses (hemagglutination-HA titers) and complement fixation (CF) titers in mature does of the two breeds to chicken red blood cells (c-RBC). The HA titers showed a significant seroconversion only in imported Saanen (p<0.05) but not in local does; however, the CF titers increased significantly at 4 weeks following priming with c-RBC in local (p<0.05) but not in the imported Saanen does. The impact of the differences in blood immune components and responses to antigens in the compared goats on protection potential against prevalent diseases in the sub-tropical zone of the eastern Mediterranean countries is discussed.


Asunto(s)
Cabras/inmunología , Cabras/fisiología , Leche/citología , Adaptación Fisiológica , Distribución por Edad , Análisis de Varianza , Animales , Antígenos/análisis , Análisis Químico de la Sangre/veterinaria , Recuento de Células/veterinaria , Pollos , Pruebas de Fijación del Complemento/veterinaria , Eritrocitos/química , Femenino , Cabras/sangre , Cabras/genética , Pruebas de Hemaglutinación/veterinaria , Lactancia , Masculino , Medio Oriente , Leche/inmunología , Leche/metabolismo , Distribución Aleatoria , Distribución por Sexo , Clima Tropical
17.
Vet Ital ; 47(4): 461-8, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22194228

RESUMEN

This study was designed to examine the impact of competitive non-protective antigens in a bivalent killed vaccine of Newcastle disease virus and infectious bronchitis (IB) virus on seroconversions against protective fusion protein of Newcastle disease (ND) virus (NDV), in free-range layers primed by live ND-clone 30 and IB-H120 vaccines. The experimental design included two free-range layer farms in which sera of randomly chosen layers were collected on two occasions from each of the two farms namely: at the time of administration of the killed booster vaccine (23 weeks of age) and three weeks later. The Western immunoblotting technique was used to react the individual pooled sera collected at different times from each farm with antigens used in priming, namely those of the ND-clone 30 virus and the IB-H120 virus. The optical density bands formed by reactions were compared statistically between seroconverted antibodies at 23 weeks with those of layers aged 26 weeks. The killed booster vaccine offered a significant seroconversion on both farms to the non-protective L-protein (248.0 kDa) of NDV and on one of the two farms to the non-protective NDV-matrix protein (40.0 kDa) (p<0.05). However, seroconversion to the protective fusion protein of NDV (60 kDa) failed on both farms (p<0.05). In addition, on one farm, a statistical significance was revealed by the killed booster vaccine seroconversion to non-protective IBV-nucleocapsid protein (510 kDa) and, on the other farm, to another non-protective IBV-glycoprotein (28.0 kDa) (p<0.05). The impact of competitive seroconversions to non-protective antigens and seroconversion failures to low molecular weights of NDV protective fusion protein is discussed.


Asunto(s)
Antígenos Virales/inmunología , Pollos/inmunología , Inmunización Secundaria , Enfermedad de Newcastle/prevención & control , Virus de la Enfermedad de Newcastle/inmunología , Enfermedades de las Aves de Corral/inmunología , Enfermedades de las Aves de Corral/prevención & control , Vacunas de Productos Inactivados/inmunología , Vacunas Virales/inmunología , Animales
18.
PLoS One ; 6(10): e26818, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22046370

RESUMEN

Human infections with H5, H7, and H9 avian influenza viruses are well documented. Exposure to poultry is the most important risk factor for humans becoming infected with these viruses. Data on human infection with other low pathogenicity avian influenza viruses is sparse but suggests that such infections may occur. Lebanon is a Mediterranean country lying under two major migratory birds flyways and is home to many wild and domestic bird species. Previous reports from this country demonstrated that low pathogenicity avian influenza viruses are in circulation but highly pathogenic H5N1 viruses were not reported. In order to study the extent of human infection with avian influenza viruses in Lebanon, we carried out a seroprevalence cross-sectional study into which 200 poultry-exposed individuals and 50 non-exposed controls were enrolled. We obtained their sera and tested it for the presence of antibodies against avian influenza viruses types H4 through H16 and used a questionnaire to collect exposure data. Our microneutralization assay results suggested that backyard poultry growers may have been previously infected with H4 and H11 avian influenza viruses. We confirmed these results by using a horse red blood cells hemagglutination inhibition assay. Our data also showed that farmers with antibodies against each virus type clustered in a small geographic area suggesting that unrecognized outbreaks among birds may have led to these human infections. In conclusion, this study suggests that occupational exposure to chicken is a risk factor for infection with avian influenza especially among backyard growers and that H4 and H11 influenza viruses may possess the ability to cross the species barrier to infect humans.


Asunto(s)
Virus de la Influenza A , Gripe Aviar/transmisión , Gripe Humana/transmisión , Exposición Profesional , Adulto , Agricultura , Crianza de Animales Domésticos , Animales , Estudios de Casos y Controles , Pollos , Femenino , Humanos , Gripe Aviar/virología , Gripe Humana/virología , Líbano , Masculino , Persona de Mediana Edad
19.
Med Sci Monit ; 16(10): BR333-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20885346

RESUMEN

BACKGROUND: Highly virulent Avian Influenza viruses might arise from avirulent strains following viral passaging. This work aims at studying the impact of embryonic passaging of H9N2 on the stability of the HA1 amino acid sequence and its relatedness to pathogenicity. MATERIAL/METHODS: The original H9N2 virus was propagated for 3 consecutive passages in embryonated chicken eggs. Pathogenicity and amino acids sequences at the HA1 gene level of the original (P0), and the once (P1), twice (P2), and three times (P3) passaged viruses were compared. RESULTS: The percent mortality significantly increased in embryos inoculated with P2 (86.7%) and P3 of H9N2 (100%) in comparison to P0 (0.0%) and P1 of H9N2 (46.1%) (P<0.05), while the density of propagated H9N2 declined with passaging. The R-S-S-R motif was stable at the HA1 cleavage site of P0, P1, P2, and P3 viruses. The similarity in the HA1 sequences among the differently passaged viruses ranged between 93.2 to 100%. CONCLUSIONS: The pathogenicity increased significantly upon passaging in chicken embryos in spite of the presence of the same motif at the HA1 cleavage site. Further investigations will target the study of changes in the whole HA protein and of Neuraminidases that could be responsible for a higher pathogenicity.


Asunto(s)
Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Subtipo H9N2 del Virus de la Influenza A/patogenicidad , Gripe Aviar/fisiopatología , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Embrión de Pollo , Pollos/genética , Pollos/inmunología , Pollos/virología , Subtipo H9N2 del Virus de la Influenza A/genética , Subtipo H9N2 del Virus de la Influenza A/inmunología , Virus de la Influenza A/genética , Virus de la Influenza A/inmunología , Virus de la Influenza A/patogenicidad
20.
Vet Ital ; 46(3): 319-27, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20857381

RESUMEN

The aim of this survey was to study Koch's postulate of Arcanobacterium pyogenes recovered from the necrotic lung of a kid and to compare the immunogenicity of this isolate in local and imported Saanen goats. The disease was successfully reproduced in intrathoracically challenged hamsters which showed lung congestion and liver abscesses, while hamsters that were intraperitoneally challenged showed only the formation of intestinal abscesses. The percentage of histopathologic legions in 12 observed microscopic fields per lung of three groups of hamsters (unchallenged controls, challenged intrathoracically and challenged intraperitoneally) showed a significant increase in lung necrosis of the intrathoracically challenged group, followed by intraperitoneally challenged hamsters, in comparison to unchallenged controls (p<0.05). In addition, the frequency of mucus accumulation in alveolar ducts followed the same respective pattern (p>0.05), while there was no significant difference in the frequency of neutrophil infiltration (p>0.05). The isolate was successfully recovered from the lungs and livers of hamsters challenged by both routes. Saanen does showed significant seroconversion using the indirect haemagglutination (HA) test and slide agglutination test (SAT) and at three weeks following priming and boosting with A. pyogenes antigens (p<0.05); however, only SAT showed significant seroconversion in local does at three weeks post booster (p<0.05). The possible causes and impact of the greater immunogenicity to A. pyogenes antigens in Saanen goats compared to local does are discussed.


Asunto(s)
Arcanobacterium/inmunología , Cricetinae/inmunología , Cabras/microbiología , Animales , Arcanobacterium/aislamiento & purificación
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