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1.
Sci Rep ; 13(1): 9958, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37339992

RESUMEN

Many dimensions of human life and the environment are vulnerable to anthropogenic climate change and the hazards associated with it. There are several indices and metrics to quantify climate hazards that can inform preparedness and planning at different levels e.g., global, regional, national, and local. This study uses biased corrected climate projections of temperature and precipitation to compute characteristics of potential climate hazards that are pronounced in the Gomal Zam Dam Command Area (GZDCA)- an irrigated agricultural area in Khyber Pakhtunkhwa province of Pakistan. The results answer the question of what the future holds in the GZDCA regarding climate hazards of heatwaves, heavy precipitation, and agricultural drought. The results of heatwaves and agricultural drought present an alarming future and call for immediate actions for preparedness and adaptation. The magnitude of drought indices for the future is correlated with the crop yield response based on AquaCrop model simulations with observed climate data being used as input. This correlation provides insight into the suitability of various drought indices for agricultural drought characterization. The results elaborate on how the yield of wheat crop grown in a typical setting common in the South Asian region respond to the magnitude of drought indices. The findings of this study inform the planning process for changing climate and expected climate hazards in the GZDCA. Analyzing climate hazards for the future at the local level (administrative districts or contiguous agricultural areas) might be a more efficient approach for climate resilience due to its specificity and enhanced focus on the context.

2.
Vet Microbiol ; 276: 109603, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36423482

RESUMEN

Spotty Liver Disease (SLD) is a significant disease of commercial layer hens. It can cause up to 10 % flock mortalities and reduce egg production by 25 %. Campylobacter hepaticus has been identified as the main cause of the disease, although it also appears that predisposing factors, such as some form of stress, may increase the likelihood of clinical disease occurring. Recently, a newly identified species, Campylobacter bilis, was isolated from bile samples of clinical SLD affected chickens. To investigate the pathogenic potential of C. bilis two independent isolates were used in infection trials of layer hens. Within 6 days of oral challenge birds developed typical SLD liver lesions, demonstrating that both strains induced SLD. C. bilis could be recovered from all the challenged birds that developed SLD. Thus, each of the steps in Koch's postulates have been fulfilled, confirming that C. bilis is an additional cause of SLD. A PCR method was developed which can specifically detect C. bilis from samples with complex microbiota. The identification of this newly discovered Campylobacter species as a second cause of SLD and the provision of a rapid method to detect the SLD causing bacterium will help with SLD vaccine development and epidemiology, thus assisting in the control of this important disease of poultry.


Asunto(s)
Infecciones por Campylobacter , Campylobacter , Hepatopatías , Enfermedades de las Aves de Corral , Animales , Femenino , Pollos/microbiología , Infecciones por Campylobacter/microbiología , Infecciones por Campylobacter/veterinaria , Enfermedades de las Aves de Corral/microbiología , Hepatopatías/microbiología , Hepatopatías/veterinaria
3.
Front Vet Sci ; 9: 1058110, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36452145

RESUMEN

Spotty liver disease (SLD) caused by Campylobacter hepaticus affects the health and productivity of layer hens and is a disease of concern in poultry. In this study, blood and cloacal swab samples were collected from 709 birds across 11 free-range layer farms from different regions of Australia. The prevalence of C. hepaticus specific antibodies and DNA was assessed using a C. hepaticus specific ELISA and PCR and its correlation with mortalities and changes in egg production was analyzed to better understand the seroprevalence of C. hepaticus in Australian free-range layer farms. C. hepaticus specific antibodies were detected from birds in four of the five farms that had no history of SLD with seroprevalence as high as 41% in one of the farms. Seroprevalence of anti-C. hepaticus antibodies among flocks that had an active or previous SLD outbreak varied between 2 and 64%. C. hepaticus DNA was detected from birds in three farms with no known SLD history and five farms with confirmed SLD outbreaks. A good correlation was observed between the ELISA and PCR results with a Pearson correlation coefficient value of 0.85 (p-value = 0.001). No correlation was observed between the flock size or flock age and ELISA or PCR outcomes, and no significant difference between the seroprevalence of anti-C. hepaticus antibodies among flocks with or without a known history of SLD was established (p = 0.143). This study demonstrates the usefulness of C. hepaticus specific ELISA and PCR in identifying the occurrence of mild or sub-clinical SLD and provides a broader and more complete understanding of SLD epidemiology that will inform future research aimed at the development of methods to control SLD, such as appropriate biosecurity measures, vaccines, and feed additives.

4.
Viruses ; 14(11)2022 11 17.
Artículo en Inglés | MEDLINE | ID: mdl-36423151

RESUMEN

Spotty liver disease (SLD) causes substantial egg production losses and chicken mortality; therefore, it is a disease that concerns Australian egg farmers. Over the last few decades, much research has been conducted to determine the etiologic agents of SLD and to develop potential therapeutics; however, SLD still remains a major issue for the chicken industries globally and remained without the elucidation of potentially multiple pathogens involved. To help fill this gap, this study was aimed at understanding the viral diversity of bile samples from which the SLD-causing bacterium, Campylobacter hepaticus, has been isolated and characterised. The collected samples were processed and sequenced using high-throughput next-generation sequencing. Remarkably, this study found 15 galliform chaphamaparvoviruses (GaChPVs), of which 14 are novel under the genus Chaphamaparvovirus. Among them, nine were complete genomes that showed between 41.7% and 78.3% genome-wide pairwise similarities to one another. Subsequent phylogenetic analysis using the NS1 gene exhibited a multiple incursion of chaphamaparvovirus lineages, including a novel lineage of unknown ancestral history in free-range laying chickens in Australia. This is the first evidence of circulating many parvoviruses in chickens in Australia, which has increased our knowledge of the pathogen diversity that may have an association with SLD in chickens.


Asunto(s)
Infecciones por Campylobacter , Hepatopatías , Enfermedades de las Aves de Corral , Animales , Pollos , Infecciones por Campylobacter/microbiología , Infecciones por Campylobacter/veterinaria , Bilis , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/microbiología , Viroma , Filogenia , Australia/epidemiología
5.
Front Vet Sci ; 9: 1039774, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36387407

RESUMEN

Spotty Liver Disease (SLD) is a serious infectious disease which occurs mainly in laying chickens in free range production systems. SLD outbreaks can increase mortality and decrease egg production of chickens, adversely impact welfare and cause economic hardship for poultry producers. The bacterium Campylobacter hepaticus is the primary cause of the disease. This study aimed to identify the effects of C. hepaticus on chicken gut microbiota and gut structure. Three C. hepaticus strains (HV10T, NSW44L and QLD19L), isolated from different states of Australia, were used in the study. Chickens at 26-weeks post-hatch were orally dosed with one of the C. hepaticus strains (challenged groups) or Brucella broth (unchallenged or control group). Six days after the challenge, birds were necropsied to assess liver damage, and caecal content and tissue samples were collected for histology, microbiology, and 16S rRNA gene amplicon sequencing to characterize the composition of the bacterial microbiota. Strain C. hepaticus NSW44L produced significantly more disease compared to the other C. hepaticus strains and this coincided with more adverse changes observed in the caecal microbiota of the birds challenged with this strain compared to the control group. Microbial diversity determined by Shannon and Simpson alpha diversity indices was lower in the NSW44L challenged groups compared to the control group (p = 0.009 and 0.0233 respectively, at genus level). Short-chain fatty acids (SCFAs) producing bacteria Faecalibacterium, Bifidobacterium and Megamonas were significantly reduced in the challenged groups compared to the unchallenged control group. Although SLD-induction affected the gut microbiota of chickens, their small intestine morphology was not noticeably affected as there were no significant differences in the villus height or ratio of villus height and crypt depth. As gut health plays a pivotal role in the overall health and productivity of chickens, approaches to improve the gut health of the birds during SLD outbreaks such as through diet and keeping the causes of stress to a minimum, may represent significant ways to alleviate the impact of SLD.

6.
Front Vet Sci ; 9: 1082358, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36619951

RESUMEN

Campylobacter hepaticus is the aetiological agent of Spotty Liver Disease (SLD). SLD can cause significant production loss and mortalities among layer hens at and around peak of lay. We previously developed an enzyme linked immunosorbent assay (ELISA), SLD-ELISA1, to detect C. hepaticus specific antibodies from bird sera using C. hepaticus total proteins and sera pre-absorbed with Campylobacter jejuni proteins. The high specificity achieved with SLD-ELISA1 indicated the presence of C. hepaticus specific antibodies in sera of infected birds. However, some of the reagents used in SLD-ELISA1 are time consuming to prepare and difficult to quality control. This understanding led to the search for C. hepaticus specific immunogenic proteins that could be used in recombinant forms as antibody capture antigens in immunoassay design. In this study, an immunoproteomic approach that combined bioinformatics analysis, western blotting, and LC MS/MS protein profiling was used, and a fragment of filamentous hemagglutinin adhesin (FHA), FHA1,628-1,899 with C. hepaticus specific antigenicity was identified. Recombinant FHA1,628-1,899 was used as antigen coating on ELISA plates to capture FHA1,628-1,899 specific antibodies in sera of infected birds. SLD-ELISA2, based on the purified recombinant FHA fragment, is more user-friendly and standardizable than SLD-ELISA1 for screening antibody responses to C. hepaticus exposure in hens. This study is the first report of the use of FHA from a Campylobacter species in immunoassays, and it also opens future research directions to investigate the role of FHA in C. hepaticus pathogenesis and its effectiveness as a vaccine candidate.

7.
Poult Sci ; 100(11): 101423, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34534853

RESUMEN

Spotty liver disease (SLD) is a serious condition affecting extensively housed laying hens. The causative bacterium was described in 2015 and characterized in 2016 and named Campylobacter hepaticus. Antibiotics are the only tool currently available to combat SLD. However, antimicrobial resistance has already been detected, so finding therapeutic alternatives is imperative. Isoquinoline alkaloids (IQA), such as sanguinarine and chelerythrine, have been shown to have immunomodulatory effects. It has been hypothesized that IQA could ameliorate some of the deleterious effects of SLD. This study aimed to address that hypothesis in an experimental disease induction model. Birds were fed with diets containing 2 different doses of an IQA containing product, 100 mg of product/kg of feed (0.5 ppm of sanguinarine) and 200 mg of product/kg of feed (1.0 ppm of sanguinarine). Two additional groups remained untreated (a challenged positive control and an unchallenged negative control). After 4 wk of treatment, birds from all groups except the negative control group were exposed to C. hepaticus strain HV10. The IQA treated groups showed a reduction in the number of miliary lesions on the liver surface and reduced lesion scores compared with untreated hens. A significant reduction of egg mass was detected 6 d after exposure to C. hepaticus in the untreated group (P = 0.02). However, there was not a significant drop in egg-mass in the IQA groups, especially those fed with a high dose of IQA (P = 0.93). IQA supplementation did not produce significant changes in intestinal villus height and crypt depth but did result in a significant reduction in the proinflammatory cytokine, interleukin-8, in the blood (P < 0.01). Microbiota analysis showed that IQA treatment did not alter the alpha diversity of the cecal microbiota but did produce changes in the phylogenetic structure, with the higher dose of IQA increasing the Firmicutes/Bacteroidetes ratio. Other minor changes in production indicators included an increase in feed consumption (P < 0.01) and an increase in body weight of the treated hens (P < 0.0001). The present study has demonstrated that IQA confers some protection of chickens from the impact of SLD.


Asunto(s)
Infecciones por Campylobacter , Hepatopatías , Enfermedades de las Aves de Corral , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Campylobacter , Infecciones por Campylobacter/veterinaria , Pollos , Dieta/veterinaria , Suplementos Dietéticos , Femenino , Isoquinolinas , Hepatopatías/veterinaria , Filogenia , Enfermedades de las Aves de Corral/prevención & control
8.
Viruses ; 13(5)2021 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-33925055

RESUMEN

The COVID-19 pandemic has affected all individuals across the globe in some way. Despite large numbers of reported seroprevalence studies, there remains a limited understanding of how the magnitude and epitope utilization of the humoral immune response to SARS-CoV-2 viral anti-gens varies within populations following natural infection. Here, we designed a quantitative, multi-epitope protein microarray comprising various nucleocapsid protein structural motifs, including two structural domains and three intrinsically disordered regions. Quantitative data from the microarray provided complete differentiation between cases and pre-pandemic controls (100% sensitivity and specificity) in a case-control cohort (n = 100). We then assessed the influence of disease severity, age, and ethnicity on the strength and breadth of the humoral response in a multi-ethnic cohort (n = 138). As expected, patients with severe disease showed significantly higher antibody titers and interestingly also had significantly broader epitope coverage. A significant increase in antibody titer and epitope coverage was observed with increasing age, in both mild and severe disease, which is promising for vaccine efficacy in older individuals. Additionally, we observed significant differences in the breadth and strength of the humoral immune response in relation to ethnicity, which may reflect differences in genetic and lifestyle factors. Furthermore, our data enabled localization of the immuno-dominant epitope to the C-terminal structural domain of the viral nucleocapsid protein in two independent cohorts. Overall, we have designed, validated, and tested an advanced serological assay that enables accurate quantitation of the humoral response post natural infection and that has revealed unexpected differences in the magnitude and epitope utilization within a population.


Asunto(s)
Anticuerpos Antivirales/inmunología , COVID-19/inmunología , SARS-CoV-2/inmunología , Adolescente , Adulto , Antígenos Virales/inmunología , COVID-19/epidemiología , COVID-19/virología , Prueba Serológica para COVID-19 , Estudios de Casos y Controles , Estudios de Cohortes , Epítopos , Etnicidad , Femenino , Humanos , Inmunidad Humoral , Inmunoglobulina G/inmunología , Masculino , Persona de Mediana Edad , Proteínas de la Nucleocápside/genética , Proteínas de la Nucleocápside/inmunología , Pandemias , SARS-CoV-2/genética , Sensibilidad y Especificidad , Estudios Seroepidemiológicos , Índice de Severidad de la Enfermedad , Adulto Joven
9.
Environ Toxicol Chem ; 40(3): 735-743, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32274818

RESUMEN

Per- and polyfluoroalkyl substances (PFAS) have been used in aqueous film-forming foams used in firefighting, resulting in soil and groundwater contamination and leading to human exposure via animal products grown in contaminated areas. The present study reports the relationship between PFAS intake by hens and the PFAS concentrations in the edible parts of eggs. Laying hens were exposed via drinking water to different concentrations of 4 PFAS compounds (perfluorooctane sulfonate [PFOS], perfluorohexane sulfonate [PFHxS], perfluorooctanoic acid [PFOA], and perfluorohexanoic acid) over 61 d. Egg PFAS residues were assessed for a further 30 d after exposure ceased. The target concentrations of PFAS were 0, 0.3, 3, 30, and 300 µg/L for the treatment groups T1-T5, respectively; and PFAS residues were determined from the eggs collected every second day. There was a linear correlation between the PFAS concentrations in the drinking water of hens and those detected in the egg, which could be useful in estimating PFAS concentrations in the egg by measuring water concentrations. Exposure of hens to drinking water with PFAS concentrations below the Australian Government Department of Health limits (PFOS and PFHxS, 0.07 µg/L; PFOA, 0.56 µg/L), and with no other sources of PFAS exposure, is unlikely to result in egg PFAS concentrations that would exceed the 10% limit set by Food Standards Australia New Zealand for human consumption. Environ Toxicol Chem 2021;40:735-743. © 2020 SETAC.


Asunto(s)
Ácidos Alcanesulfónicos , Agua Potable , Fluorocarburos , Agua Subterránea , Contaminantes Químicos del Agua , Ácidos Alcanesulfónicos/análisis , Animales , Australia , Pollos , Agua Potable/análisis , Femenino , Fluorocarburos/análisis , Humanos , Contaminantes Químicos del Agua/análisis
10.
Avian Pathol ; 49(6): 658-665, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32835491

RESUMEN

Spotty Liver Disease (SLD) is an emerging disease of serious concern in the egg production industry, as it causes significant egg loss and mortality in layer hens. The causative agent is a newly identified Gram-negative bacterium, Campylobacter hepaticus, and knowledge about C. hepaticus pathogenesis and the potential for vaccine development is still in its infancy. Current detection methods for SLD, such as PCR and culturing, only detect an active infection and will not give any indication of a past infection from which the bacteria have been cleared. An immunological assay, on the other hand, can provide information on previous infections and therefore is crucial in vaccine development against SLD. In the present study, we have developed the first immunoassay capable of detecting C. hepaticus-specific antibodies present in the sera of infected birds. The assay uses C. hepaticus total protein extract (TPE) as the antigen coating on enzyme-linked immunosorbent assay (ELISA) plates. The cross reactivity of C. hepaticus antibodies with closely related C. jejuni and C. coli antigens was successfully overcome by pre-absorbing the sera using C. jejuni cell extracts. The assay was validated using sera samples from both naturally- and experimentally-infected birds, birds vaccinated with formalin-killed bacteria, and serum samples from SLD-negative birds (control group). The optimized ELISA assay had 95.5% specificity and 97.6% sensitivity. The immunoassay provides a useful tool for monitoring the exposure of poultry flocks to C. hepaticus infection and can be used to direct and support vaccine development. HIGHLIGHTS The first immunoassay developed for Spotty Liver Disease (SLD). A useful method for detecting C. hepaticus-specific antibodies in birds. Highly specific (95.5%) and sensitive (97.6%) assay. A key tool for use in epidemiological studies and vaccine development.


Asunto(s)
Vacunas Bacterianas/inmunología , Infecciones por Campylobacter/veterinaria , Campylobacter/inmunología , Pollos/microbiología , Hepatopatías/veterinaria , Enfermedades de las Aves de Corral/diagnóstico , Animales , Infecciones por Campylobacter/diagnóstico , Infecciones por Campylobacter/microbiología , Infecciones por Campylobacter/prevención & control , Ensayo de Inmunoadsorción Enzimática/veterinaria , Hígado/microbiología , Hepatopatías/diagnóstico , Hepatopatías/microbiología , Aves de Corral , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/prevención & control
11.
Front Microbiol ; 10: 107, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30804905

RESUMEN

Chickens infected with Campylobacter jejuni or Campylobacter coli are largely asymptomatic, however, infection with the closely related species, Campylobacter hepaticus, can result in Spotty Liver Disease (SLD). C. hepaticus has been detected in the liver, bile, small intestine and caecum of SLD affected chickens. The survival and colonization mechanisms that C. hepaticus uses to colonize chickens remain unknown. In this study, we compared the genome sequences of 14 newly sequenced Australian isolates of C. hepaticus, isolates from outbreaks in the United Kingdom, and reference strains of C. jejuni and C. coli, with the aim of identifying virulence genes associated with SLD. We also carried out global comparative transcriptomic analysis between C. hepaticus recovered from the bile of SLD infected chickens and C. hepaticus grown in vitro. This revealed how the bacteria adapt to proliferate in the challenging host environment in which they are found. Additionally, biochemical experiments confirmed some in silico metabolic predictions. We found that, unlike other Campylobacter sp., C. hepaticus encodes glucose and polyhydroxybutyrate metabolism pathways. This study demonstrated the metabolic plasticity of C. hepaticus, which may contribute to survival in the competitive, nutrient and energy-limited environment of the chicken. Transcriptomic analysis indicated that gene clusters associated with glucose utilization, stress response, hydrogen metabolism, and sialic acid modification may play an important role in the pathogenicity of C. hepaticus. An understanding of the survival and virulence mechanisms that C. hepaticus uses will help to direct the development of effective intervention methods to protect birds from the debilitating effects of SLD.

12.
Front Vet Sci ; 6: 505, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32010715

RESUMEN

The epidemiology of Spotty Liver Disease (SLD) was investigated by assaying 1,840 samples collected from layer chickens and the environment in poultry farms across Australia for the presence of Campylobacter hepaticus, the agent responsible SLD in chickens. A C. hepaticus specific PCR and bacterial culture were used. Results showed that birds could be infected with C. hepaticus up to 8 weeks before clinical SLD was manifested. In addition, birds could be infected long before laying starts, as young as 12 weeks old, but the peak period for SLD outbreaks was when the birds were 26-27 weeks old. Campylobacter hepaticus DNA was detected in motile organisms such as wild birds and rats and so these organisms may be vectors for C. hepaticus dissemination. Moreover, water, soil, mites, flies, and dust samples from SLD infected farms were also found to be PCR-positive for C. hepaticus DNA. However, it still remains to be determined whether these environmental sources carry any viable C. hepaticus. The indications from this study are that environmental sources are a likely transmission source of C. hepaticus. Therefore, biosecurity practices need to be strictly followed to prevent the spread of SLD amongst and between flocks. Also, a rapid, molecular detection method such as PCR should be used as to monitor for C. hepaticus presence in flocks before clinical disease is apparent, and therefore inform the use of biosecurity and therapeutic measures to help prevent SLD outbreaks.

13.
Foodborne Pathog Dis ; 15(8): 526-530, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29356597

RESUMEN

Campylobacter jejuni and Campylobacter coli play a major role in bacteria-related foodborne illness in humans. Recently, a newly identified species, Campylobacter hepaticus, was shown to be the causative agent of spotty liver disease in chickens. The pathogenic potential of C. hepaticus in humans is unknown. This new species contains genes usually used to detect C. jejuni and C. coli in DNA-based detection methods, such as the hippuricase (hipO) gene and the glyA (serine hydroxymethyltransferase) gene, with a high degree of similarity. Therefore, polymerase chain reaction (PCR) primers used to detect these species need to be evaluated carefully to prevent misidentification of these important Campylobacter species. A multiplex PCR was developed and optimized to simultaneously and specifically identify the presence of C. jejuni, C. coli, and C. hepaticus in chicken samples containing high-complexity microbiota. The assay represents a new diagnostic tool for investigating the epidemiology of Campylobacter colonization in poultry and environmental samples. It may also be applicable to the investigation of Campylobacter contamination in food and in outbreaks of campylobacteriosis.


Asunto(s)
Infecciones por Campylobacter/veterinaria , Campylobacter/clasificación , Pollos/microbiología , Hepatopatías/veterinaria , Enfermedades de las Aves de Corral/microbiología , Animales , Técnicas de Tipificación Bacteriana , Campylobacter/genética , Campylobacter/aislamiento & purificación , Infecciones por Campylobacter/microbiología , ADN Bacteriano/genética , Hepatopatías/microbiología , Reacción en Cadena de la Polimerasa Multiplex , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
14.
PLoS One ; 12(8): e0182524, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28797043

RESUMEN

Rapid progress in next generation sequencing and allied computational tools have aided in identification of single nucleotide variants in genomes of several organisms. In the present study, we have investigated single nucleotide polymorphism (SNP) in ten multi-antibiotic resistant Pseudomonas aeruginosa clinical isolates. All the draft genomes were submitted to Rapid Annotations using Subsystems Technology (RAST) web server and the predicted protein sequences were used for comparison. Non-synonymous single nucleotide polymorphism (nsSNP) found in the clinical isolates compared to the reference genome (PAO1), and the comparison of nsSNPs between antibiotic resistant and susceptible clinical isolates revealed insights into the genome variation. These nsSNPs identified in the multi-drug resistant clinical isolates were found to be altering a single amino acid in several antibiotic resistant genes. We found mutations in genes encoding efflux pump systems, cell wall, DNA replication and genes involved in repair mechanism. In addition, nucleotide deletions in the genome and mutations leading to generation of stop codons were also observed in the antibiotic resistant clinical isolates. Next generation sequencing is a powerful tool to compare the whole genomes and analyse the single base pair variations found within the antibiotic resistant genes. We identified specific mutations within antibiotic resistant genes compared to the susceptible strain of the same bacterial species and these findings may provide insights to understand the role of single nucleotide variants in antibiotic resistance.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana/genética , Pseudomonas aeruginosa/genética , Pruebas Antimicrobianas de Difusión por Disco , Genoma Bacteriano , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Polimorfismo de Nucleótido Simple , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/microbiología , Pseudomonas aeruginosa/efectos de los fármacos , Análisis de Secuencia de ADN
15.
Vet Microbiol ; 207: 226-230, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28757028

RESUMEN

Spotty liver disease (SLD) causes significant egg production losses and mortality in chickens and is therefore a disease of concern for some sectors of the poultry industry. Although the first reports of the disease came from the United States in the 1950s it is only recently that the organism that causes the disease was identified, isolated, and characterised as a new bacterial species, Campylobacter hepaticus. The first isolations of C. hepaticus were from the livers and bile of SLD affected birds. Isolates could only be recovered from samples that had a monoculture of C. hepaticus in the tissues, as a selective culturing method has not yet been developed. In non-selective growth conditions the slow growing C. hepaticus is quickly outgrown by many other members of the chicken microbiota. Therefore, it is currently not possible to use a culturing approach to evaluate C. hepaticus carriage in tissues, such as the gastrointestinal tract (GIT), that also carry complex microbial populations. As it is suspected that birds become infected via the faecal-oral route it is important that pathogen carriage in the GIT is investigated. In the present study, a specific and sensitive quantitative real-time PCR assay, based on the glycerol kinase gene of C. hepaticus, was developed. The assay facilitated the detection and quantification of C. hepaticus in tissue samples from clinical cases of SLD. It was shown that in infected birds C. hepaticus colonises the small intestine, increasing in abundance from duodenum to ileum, and is at highest levels within the ceaca. C. hepaticus was also readily detected in cloacal swabs, indicating that thecl-oral infection.


Asunto(s)
Infecciones por Campylobacter/veterinaria , Campylobacter/clasificación , Pollos , Intestino Delgado/microbiología , Hepatopatías/veterinaria , Enfermedades de las Aves de Corral/microbiología , Animales , Infecciones por Campylobacter/microbiología , Ciego/microbiología , Hepatopatías/microbiología , Reacción en Cadena de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa/veterinaria , Sensibilidad y Especificidad , Especificidad de la Especie
16.
PLoS One ; 12(4): e0174865, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28384287

RESUMEN

BACKGROUND: Cancers of the oral cavity are primarily oral squamous cell carcinomas (OSCCs). Many of the OSCCs present at late stages with an exceptionally poor prognosis. A probable limitation in management of patients with OSCC lies in the insufficient knowledge pertaining to the linkage between copy number alterations in OSCC and oral tumourigenesis thereby resulting in an inability to deliver targeted therapy. OBJECTIVES: The current study aimed to identify copy number alterations (CNAs) in OSCC using array comparative genomic hybridization (array CGH) and to correlate the CNAs with clinico-pathologic parameters and clinical outcomes. MATERIALS AND METHODS: Using array CGH, genome-wide profiling was performed on 75 OSCCs. Selected genes that were harboured in the frequently amplified and deleted regions were validated using quantitative polymerase chain reaction (qPCR). Thereafter, pathway and network functional analysis were carried out using Ingenuity Pathway Analysis (IPA) software. RESULTS: Multiple chromosomal regions including 3q, 5p, 7p, 8q, 9p, 10p, 11q were frequently amplified, while 3p and 8p chromosomal regions were frequently deleted. These findings were in confirmation with our previous study using ultra-dense array CGH. In addition, amplification of 8q, 11q, 7p and 9p and deletion of 8p chromosomal regions showed a significant correlation with clinico-pathologic parameters such as the size of the tumour, metastatic lymph nodes and pathological staging. Co-amplification of 7p, 8q, 9p and 11q regions that harbored amplified genes namely CCND1, EGFR, TPM2 and LRP12 respectively, when combined, continues to be an independent prognostic factor in OSCC. CONCLUSION: Amplification of 3q, 5p, 7p, 8q, 9p, 10p, 11q and deletion of 3p and 8p chromosomal regions were recurrent among OSCC patients. Co-alteration of 7p, 8q, 9p and 11q was found to be associated with clinico-pathologic parameters and poor survival. These regions contain genes that play critical roles in tumourigenesis pathways.


Asunto(s)
Carcinoma de Células Escamosas/genética , Perfilación de la Expresión Génica , Neoplasias de la Boca/genética , Adulto , Carcinoma de Células Escamosas/patología , Hibridación Genómica Comparativa , Variaciones en el Número de Copia de ADN , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/patología , Pronóstico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
17.
Vet Microbiol ; 199: 85-90, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28110791

RESUMEN

Spotty liver disease (SLD) in chickens can present with variable impacts on mortality and production, ranging from sporadic mortalities of individual birds and no notable impact on production to severe reduction in egg output and increased mortality in layer flocks of greater than 1% per day. It was first described over 60 years ago and there have been sporadic reports of the disease throughout the intervening decades, particularly in the US, UK and Germany. Recently it has become of increasing concern as outbreaks of the disease have occurred more frequently, particularly in the Australian poultry industry. An understanding of the causes of the disease has proven elusive. However, recent studies of SLD have strongly implicated a novel Campylobacter species, Campylobacter hepaticus, as the causative agent. Here we demonstrate that C. hepaticus is highly invasive in LMH cells, an immortalised chicken hepatoma cell line, and can induce disease when orally delivered to mature layer birds. Challenged birds developed liver lesions, typical of those seen in field clinical cases, within 5days of challenge. The bacterium used to challenge the birds could be recovered from the diseased liver and from bile, thus demonstrating that C. hepaticus is the causative agent of chicken SLD.


Asunto(s)
Infecciones por Campylobacter/veterinaria , Campylobacter/fisiología , Hepatopatías/veterinaria , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/patología , Animales , Australia , Bilis/microbiología , Campylobacter/aislamiento & purificación , Infecciones por Campylobacter/patología , Línea Celular Tumoral , Pollos/microbiología , Femenino , Hígado/microbiología , Hepatopatías/microbiología , Hepatopatías/patología
18.
PLoS One ; 11(6): e0157901, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27355363

RESUMEN

Toxoplasmosis is a widespread parasitic infection by Toxoplasma gondii, a parasite with at least three distinct clonal lineages. This article reports the whole genome sequencing and de novo assembly of T. gondii RH (type I representative strain), as well as genome-wide comparison across major T. gondii lineages. Genomic DNA was extracted from tachyzoites of T. gondii RH strain and its identity was verified by PCR and LAMP. Subsequently, whole genome sequencing was performed, followed by sequence filtering, genome assembly, gene annotation assignments, clustering of gene orthologs and phylogenetic tree construction. Genome comparison was done with the already archived genomes of T. gondii. From this study, the genome size of T. gondii RH strain was found to be 69.35Mb, with a mean GC content of 52%. The genome shares high similarity to the archived genomes of T. gondii GT1, ME49 and VEG strains. Nevertheless, 111 genes were found to be unique to T. gondii RH strain. Importantly, unique genes annotated to functions that are potentially critical for T. gondii virulence were found, which may explain the unique phenotypes of this particular strain. This report complements the genomic archive of T. gondii. Data obtained from this study contribute to better understanding of T. gondii and serve as a reference for future studies on this parasite.


Asunto(s)
Genoma de Protozoos , Toxoplasma/genética , Toxoplasmosis/genética , Algoritmos , Animales , Composición de Base , Biología Computacional , Bases de Datos de Proteínas , Genómica , Ratones , Anotación de Secuencia Molecular , Filogenia , Especificidad de la Especie , Virulencia
19.
PLoS One ; 11(4): e0153725, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27100827

RESUMEN

Parkinson's disease (PD) is the second most common chronic and progressive neurodegenerative disorder. Its etiology remains elusive and at present only symptomatic treatments exists. Helicobacter pylori chronically colonizes the gastric mucosa of more than half of the global human population. Interestingly, H. pylori positivity has been found to be associated with greater of PD motor severity. In order to investigate the underlying cause of this association, the Sengenics Immunome protein array, which enables simultaneous screening for autoantibodies against 1636 human proteins, was used to screen the serum of 30 H. pylori-seropositive PD patients (case) and 30 age- and gender-matched H. pylori-seronegative PD patients (control) in this study. In total, 13 significant autoantibodies were identified and ranked, with 8 up-regulated and 5 down-regulated in the case group. Among autoantibodies found to be elevated in H. pylori-seropositive PD were included antibodies that recognize Nuclear factor I subtype A (NFIA), Platelet-derived growth factor B (PDGFB) and Eukaryotic translation initiation factor 4A3 (eIFA3). The presence of elevated autoantibodies against proteins essential for normal neurological functions suggest that immunomodulatory properties of H. pylori may explain the association between H. pylori positivity and greater PD motor severity.


Asunto(s)
Autoanticuerpos/inmunología , Infecciones por Helicobacter/complicaciones , Infecciones por Helicobacter/inmunología , Helicobacter pylori/inmunología , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/inmunología , Anciano , Autoanticuerpos/sangre , Factor 4A Eucariótico de Iniciación/inmunología , Femenino , Infecciones por Helicobacter/sangre , Infecciones por Helicobacter/microbiología , Humanos , Masculino , Persona de Mediana Edad , Factores de Transcripción NFI/inmunología , Enfermedad de Parkinson/sangre , Enfermedad de Parkinson/microbiología , Proteínas Proto-Oncogénicas c-sis/inmunología
20.
Head Neck ; 38 Suppl 1: E783-97, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-25914319

RESUMEN

BACKGROUND: This purpose of this meta-analysis study was to identify the most frequent and potentially significant copy number alteration (CNA) in oral carcinogenesis. METHODS: Seven oral squamous cell carcinoma (OSCC)-related publications, corresponding to 312 samples, were identified for this meta-analysis. The data were analyzed in a 4-step process that included the genome assembly coordination of multiple platforms, assignment of chromosomal position anchors, calling gains and losses, and functional annotation analysis. RESULTS: Gains were more frequent than losses in the entire dataset. High-frequency gains were identified in chromosomes 5p, 14q, 11q, 7p, 17q, 20q, 8q, and 3q, whereas high-frequency losses were identified in chromosomes 3p, 8p, 6p, 18q, and 4q. Ingenuity pathway analysis showed that the top biological function was associated with immortalization of the epithelial cells (p = 1.93E-04). CONCLUSION: This study has identified multiple recurrent CNAs that are involved in various biological annotations associated with oral carcinogenesis. © 2015 Wiley Periodicals, Inc. Head Neck 38: E783-E797, 2016.


Asunto(s)
Carcinogénesis , Carcinoma de Células Escamosas/genética , Variaciones en el Número de Copia de ADN , Células Epiteliales/patología , Neoplasias de la Boca/genética , Carcinoma de Células Escamosas/patología , Aberraciones Cromosómicas , Hibridación Genómica Comparativa , Humanos , Neoplasias de la Boca/patología
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