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1.
Sci Rep ; 14(1): 8111, 2024 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582950

RESUMO

Colisepticaemia caused by avian pathogenic Escherichia coli (APEC) is a challenging disease due to its high economic importance in poultry, dubious pathogenesis and potential link with zoonosis and food safety. The existing in vitro studies can't define hallmark traits of APEC isolates, suggesting a paradigm shift towards host response to understand pathogenesis. This study investigated the comprehensive pathological and microbial progression of colisepticaemia, and transmission of E. coli into eggs using novel tools. In total 48 hens were allocated into three groups and were inoculated intratracheally with ilux2-E. coli PA14/17480/5-/ovary (bioluminescent strain), E. coli PA14/17480/5-/ovary or phosphate buffered saline. Infection with both strains led to typical clinical signs and lesions of colibacillosis as in field outbreaks. Based on lung histopathology, colisepticaemia progression was divided into four disease stages as: stage I (1-3 days post infection (dpi)), stage II (6 dpi), stage III (9 dpi) and stage IV (16 dpi) that were histologically characterized by predominance of heterophils, mixed cells, pyogranuloma, and convalescence, respectively. As disease progressed, bacterial colonization in host organs also decreased, revealed by the quantification of bacterial bioluminescence, bacteriology, and quantitative immunohistochemistry. Furthermore, immunofluorescence, immunohistochemistry, and bacteria re-isolation showed that E. coli colonized the reproductive tract of infected hens and reached to egg yolk and albumen. In conclusion, the study provides novel insights into the pathogenesis of colisepticemia by characterizing microbial and pathological changes at different disease stages, and of the bacteria transmission to table eggs, which have serious consequences on poultry health and food safety.


Assuntos
Infecções por Escherichia coli , Doenças das Aves Domésticas , Animais , Feminino , Escherichia coli , Galinhas/microbiologia , Doenças das Aves Domésticas/microbiologia , Infecções por Escherichia coli/microbiologia , Gema de Ovo
2.
BMJ Case Rep ; 17(3)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453226

RESUMO

A young male in his mid-teen years presented with severe back pain for 3 months and was subsequently diagnosed with osteoid osteoma in the left superior articular process of the L4 vertebra. Initial treatment with non-steroidal anti-inflammatory drugs provided temporary relief. Due to concerns about scoliosis progression along with unrelieved pain, a multidisciplinary team recommended endoscopic excision of the osteoid osteoma. The procedure resulted in complete pain relief and an improvement in the scoliosis curve from 22° of Cobb's angle to 12 degrees at the 8-month follow-up.


Assuntos
Neoplasias Ósseas , Osteoma Osteoide , Escoliose , Adolescente , Humanos , Masculino , Osteoma Osteoide/diagnóstico , Osteoma Osteoide/diagnóstico por imagem , Escoliose/complicações , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Tomografia Computadorizada por Raios X , Dor , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/diagnóstico por imagem
3.
Avian Dis ; 67(4): 298-304, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38300650

RESUMO

Escherichia coli is one of the first commensal bacteria to colonize the chicken gut, where it predominates at an early stage of broiler chick life. Escherichia coli can potentially cause colibacillosis in chickens, spreading to extraintestinal systemic organs, which results in high economic losses in poultry industry, as well as a potential risk to public health. Many studies conducted to investigate the effectiveness of natural products as alternatives to antibiotics and to enhance the production performance in broiler chickens have assessed E. coli load in the chicken gut, but it is still unknown how the E. coli count is linked to broiler growth performance. A systematic search of published research articles, including key terms of interest such as broiler chickens, growth performance, and E. coli count, was conducted using two main databases (PubMed and the Web of Science). A random effects metaregression model was built to evaluate the association between E. coli count and weight gain in untreated groups of broilers (negative controls) from eligible studies. Of 2108 articles in the initial screening, 60 were included in the final meta-analysis. After data extraction, records from the ileum and cecum at 21, 35, and 42 days of age were considered for the meta-analysis. The meta-analysis showed that the average E. coli count in both the ileum and cecum at 21 days of age was positively associated with the average weight gain in the studied broiler chickens, while no statistically significant associations were found at 35 and 42 days of age. In conclusion, the positive association between E. coli load and body weight gain in young broiler chickens may be attributed to the relative dominance of E. coli in the gut of this age group when the microbial population is less diverse. The dynamic association between the production performance and the load of E. coli that has dubious pathogenic potential suggests the importance of careful assessment of commensal E. coli to develop strategies to enhance production, particularly in young broiler chickens.


Assuntos
Galinhas , Doenças das Aves Domésticas , Animais , Escherichia coli , Aumento de Peso , Peso Corporal
4.
Vet Microbiol ; 290: 109995, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38301451

RESUMO

Gallibacterium anatis is a Gram-negative bacterium found in the respiratory and genital tracts of various animals, primarily poultry. Its association with septicemia and high mortality in poultry, along with the rise in multidrug-resistant strains, has amplified concerns. Recent research uncovered significant variability in antibiotic resistance profiles among G. anatis isolates from different Austrian flocks, and even between different organs within the same bird. In response, in the present study 60 of these isolates were sequenced and a combination of comparative genomics and genome-wide association study (GWAS) analysis was applied to understand the genetic variability of G. anatis across flocks and organs and to identify genes related to antibiotic resistance. The results showed that each flock harbored one or two strains of G. anatis with only a few strains shared between flocks, demonstrating a great variability among flocks. We identified genes associated with resistance to nalidixic acid, trimethoprim, cefoxitin, tetracycline, ampicillin and sulfamethoxazole. Our findings revealed that G. anatis may develop antibiotic resistance through two mechanisms: single-nucleotide mutations and the presence of specific genes that confer resistance. Unexpectedly, some tetracycline-resistant isolates lacked all known tetracycline-associated genes, suggesting the involvement of novel mechanisms of tetracycline resistance that require additional exploration. Furthermore, our functional annotation of resistance genes highlighted the citric acid cycle pathway as a potential key modulator of antibiotic resistance in G. anatis. In summary, this study describes the first application of GWAS analysis to G. anatis and provides new insights into the acquisition of multidrug resistance in this important avian pathogen.


Assuntos
Pasteurellaceae , Doenças das Aves Domésticas , Animais , Antibacterianos/farmacologia , Estudo de Associação Genômica Ampla/veterinária , Galinhas/microbiologia , Tetraciclina , Aves Domésticas/genética , Resistência a Tetraciclina/genética , Genômica , Doenças das Aves Domésticas/microbiologia
5.
Pulm Ther ; 10(1): 123-132, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38324171

RESUMO

INTRODUCTION: Portable oxygen concentrators (POCs) are medical devices that provide supplemental oxygen to patients requiring long-term oxygen therapy. However, little information is available on day-to-day patterns of how or even whether patients actively switch between their POC mobility features and flow setting options. METHODS: A retrospective analysis was conducted to assess POC usage among patients who used an Inogen One G5 POC in the USA. This study aimed (1) to describe the patterns of use of POCs, (2) to analyze their compatibility with the prescribed oxygen therapy settings, and (3) to demonstrate the contribution of POC usage to get a standardized long-term oxygen therapy (LTOT). Data were directly downloaded from the devices returned for service or at the end of the Medicare Durable Medical Equipment rental period and streamed via a mobile application from 2018 to 2022. Daily usage, disconnections from the device, use of prescribed pulse delivery settings, breaths per minute, power sources, and movement with the POC were assessed. Device alert histories were also examined. RESULTS: Data revealed a mean daily usage of 4.29 ± 3.23 h/day, ranging from 0.35 to 15.52 h/day. The prescribed pulse delivery setting was used by 31.34% of patients for at least 80% of their POC use time. When the POC was on battery power, patients were moving/mobile 41.99 ± 33.33% of the time. On the basis of the device-generated alerts, some patients continued to use their POC very close to or even beyond the lifetime of the column/sieve bed. Alerts or alarms potentially requiring repair occurred at a rate of 1.63 events per 100 years of use, indicating that device reliability did not significantly influence the use patterns. CONCLUSION: Patients used their POCs when mobile and at rest. A large proportion of patients adjust their POC settings during the day, which potentially indicates the need for the dynamic individualization of oxygen dose delivery to match activities of daily living or sleep. Patients require follow-up to ensure timely replacement of POC columns.


This study aimed to (1) describe the patterns of use of portable oxygen concentrators (POCs), (2) analyze their compatibility with the prescribed oxygen therapy settings, and (3) demonstrate the contribution of POC usage to get a standardized long-term oxygen therapy (LTOT). A retrospective analysis was conducted on data downloaded directly from devices and streamed via a mobile application. Daily usage, disconnections from the device, use of prescribed pulse delivery settings, breaths per minute, power sources, and movement with the device were assessed. Device alert histories were also examined. Patients used their portable oxygen concentrators when mobile and at rest, and large proportion of patients adjust their settings during the day. There was a low incidence of alarms or alerts requiring repairs, indicating device reliability. Patients require follow-up to ensure timely replacement of columns.

6.
Cell Biol Int ; 48(5): 682-694, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38420874

RESUMO

Polycladida are the only free-living flatworms with a planktonic larval stage in some species. Currently, it is not clear if a larval stage is ancestral in polyclads, and which type of larva that would be. Known polyclad larvae are Müller's larva, Kato's larva and Goette's larva, differing by body shape and the number of lobes and eyes. A valuable character for the comparison and characterisation of polyclad larval types is the ultrastructural composition of the apical organ. This organ is situated at the anterior pole of the larva and is associated with at least one ciliary tuft. The larval apical organ of Theama mediterranea features two multiciliated apical tuft sensory cells. Six unfurcated apical tuft gland cell necks are sandwiched between the apical tuft sensory cells and two anchor cells and have their cell bodies located lateral to the brain. Another type of apical gland cell necks is embedded in the anchor cells. Ventral to the apical tuft, ciliated sensory neurons are present, which are neighbouring the cell necks of two furcated apical tuft gland cells. Based on the ultrastructural organisation of the apical organ and other morphological features, like a laterally flattened wedge-shaped body and three very small lobes, we recognise the larva of T. mediterranea as a new larval type, which we name Curini-Galletti's larva after its first discoverer. The ultrastructural similarities of the apical organ in different polyclad larvae support their possible homology, that is, all polyclad larvae have likely evolved from a common larva.


Assuntos
Larva , Animais
7.
Psychol Sci ; 35(3): 250-262, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38289294

RESUMO

Fundamental frequency ( fo) is the most perceptually salient vocal acoustic parameter, yet little is known about how its perceptual influence varies across societies. We examined how fo affects key social perceptions and how socioecological variables modulate these effects in 2,647 adult listeners sampled from 44 locations across 22 nations. Low male fo increased men's perceptions of formidability and prestige, especially in societies with higher homicide rates and greater relational mobility in which male intrasexual competition may be more intense and rapid identification of high-status competitors may be exigent. High female fo increased women's perceptions of flirtatiousness where relational mobility was lower and threats to mating relationships may be greater. These results indicate that the influence of fo on social perceptions depends on socioecological variables, including those related to competition for status and mates.


Assuntos
Voz , Adulto , Humanos , Masculino , Feminino , Homicídio , Percepção Social , Parceiros Sexuais
8.
J Exp Bot ; 74(21): 6820-6835, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37668551

RESUMO

Plants often face simultaneous abiotic and biotic stress conditions; however, physiological and transcriptional responses under such combined stress conditions are still not fully understood. Spring barley (Hordeum vulgare) is susceptible to Fusarium head blight (FHB), which is strongly affected by weather conditions. We therefore studied the potential influence of drought on FHB severity and plant responses in three varieties of different susceptibility. We found strongly reduced FHB severity in susceptible varieties under drought. The number of differentially expressed genes (DEGs) and strength of transcriptomic regulation reflected the concentrations of physiological stress markers such as abscisic acid or fungal DNA contents. Infection-related gene expression was associated with susceptibility rather than resistance. Weighted gene co-expression network analysis revealed 18 modules of co-expressed genes that reflected the pathogen- or drought-response in the three varieties. A generally infection-related module contained co-expressed genes for defence, programmed cell death, and mycotoxin detoxification, indicating that the diverse genotypes used a similar defence strategy towards FHB, albeit with different degrees of success. Further, DEGs showed co-expression in drought- or genotype-associated modules that correlated with measured phytohormones or the osmolyte proline. The combination of drought stress with infection led to the highest numbers of DEGs and resulted in a modular composition of the single-stress responses rather than a specific transcriptional output.


Assuntos
Fusarium , Hordeum , Hordeum/genética , Hordeum/microbiologia , Secas , Fusarium/fisiologia , Perfilação da Expressão Gênica , Transcriptoma , Doenças das Plantas/genética , Doenças das Plantas/microbiologia
9.
Antibiotics (Basel) ; 12(9)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37760758

RESUMO

Anti-microbial peptides provide a powerful toolkit for combating multidrug resistance. Combating eukaryotic pathogens is complicated because the intracellular drug targets in the eukaryotic pathogen are frequently homologs of cellular structures of vital importance in the host organism. The entomopathogenic bacteria (EPB), symbionts of entomopathogenic-nematode species, release a series of non-ribosomal templated anti-microbial peptides. Some may be potential drug candidates. The ability of an entomopathogenic-nematode/entomopathogenic bacterium symbiotic complex to survive in a given polyxenic milieu is a coevolutionary product. This explains that those gene complexes that are responsible for the biosynthesis of different non-ribosomal templated anti-microbial protective peptides (including those that are potently capable of inactivating the protist mammalian pathogen Leishmania donovanii and the gallinaceous bird pathogen Histomonas meleagridis) are co-regulated. Our approach is based on comparative anti-microbial bioassays of the culture media of the wild-type and regulatory mutant strains. We concluded that Xenorhabdus budapestensis and X. szentirmaii are excellent sources of non-ribosomal templated anti-microbial peptides that are efficient antagonists of the mentioned pathogens. Data on selective cytotoxicity of different cell-free culture media encourage us to forecast that the recently discovered "easy-PACId" research strategy is suitable for constructing entomopathogenic-bacterium (EPB) strains producing and releasing single, harmless, non-ribosomal templated anti-microbial peptides with considerable drug, (probiotic)-candidate potential.

10.
Elife ; 122023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37603466

RESUMO

Delta-like homolog 1 (Dlk1), an inhibitor of adipogenesis, controls the cell fate of adipocyte progenitors. Experimental data presented here identify two independent regulatory mechanisms, transcriptional and translational, by which Ifrd1 (TIS7) and its orthologue Ifrd2 (SKMc15) regulate Dlk1 levels. Mice deficient in both Ifrd1 and Ifrd2 (dKO) had severely reduced adipose tissue and were resistant to high-fat diet-induced obesity. Wnt signaling, a negative regulator of adipocyte differentiation, was significantly upregulated in dKO mice. Elevated levels of the Wnt/ß-catenin target protein Dlk1 inhibited the expression of adipogenesis regulators Pparg and Cebpa, and fatty acid transporter Cd36. Although both Ifrd1 and Ifrd2 contributed to this phenotype, they utilized two different mechanisms. Ifrd1 acted by controlling Wnt signaling and thereby transcriptional regulation of Dlk1. On the other hand, distinctive experimental evidence showed that Ifrd2 acts as a general translational inhibitor significantly affecting Dlk1 protein levels. Novel mechanisms of Dlk1 regulation in adipocyte differentiation involving Ifrd1 and Ifrd2 are based on experimental data presented here.


Assuntos
Adipogenia , Proteínas de Ligação ao Cálcio , Proteínas Imediatamente Precoces , Proteínas de Membrana , Animais , Camundongos , Adipócitos , Adipogenia/genética , Tecido Adiposo , Proteínas de Ligação ao Cálcio/genética , Antígenos CD36 , Diferenciação Celular , Proteínas de Membrana/genética
11.
Front Vet Sci ; 10: 1195585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37415967

RESUMO

Introduction: Colibacillosis is a worldwide prevalent disease in poultry production linked to Escherichia coli strains that belong to the avian pathogenic E. coli (APEC) pathotype. While many virulence factors have been linked to APEC isolates, no single gene or set of genes has been found to be exclusively associated with the pathotype. Moreover, a comprehensive description of the biological processes linked to APEC pathogenicity is currently lacking. Methods: In this study, we compiled a dataset of 2015 high-quality avian E. coli genomes from pathogenic and commensal isolates, based on publications from 2000 to 2021. We then conducted a genome-wide association study (GWAS) and integrated candidate gene identification with available protein-protein interaction data to decipher the genetic network underlying the biological processes connected to APEC pathogenicity. Results: Our GWAS identified variations in gene content for 13 genes and SNPs in 3 different genes associated with APEC isolates, suggesting both gene-level and SNP-level variations contribute to APEC pathogenicity. Integrating protein-protein interaction data, we found that 15 of these genes clustered in the same genetic network, suggesting the pathogenicity of APEC might be due to the interplay of different regulated pathways. We also found novel candidate genes including an uncharacterized multi-pass membrane protein (yciC) and the outer membrane porin (ompD) as linked to APEC isolates. Discussion: Our findings suggest that convergent pathways related to nutrient uptake from host cells and defense from host immune system play a major role in APEC pathogenicity. In addition, the dataset curated in this study represents a comprehensive historical genomic collection of avian E. coli isolates and constitutes a valuable resource for their comparative genomics investigations.

12.
Avian Pathol ; 52(4): 277-282, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37416969

RESUMO

Inclusion body hepatitis (IBH) is a metabolic disease affecting chickens, associated with different serotypes of fowl adenovirus (FAdV). Experimentally tested vaccines against IBH include several capsid-based subunit vaccines, but not the penton base protein. In the present study, specific pathogen-free chickens were vaccinated with recombinant penton base expressed from each of two different FAdV serotypes (FAdV-7 and FAdV-8b), followed by challenge with a virulent IBH-causing strain. No protection was observed with either vaccine, possibly due to the low immunogenicity of each protein and their inability to induce neutralizing antibodies in the host.


Assuntos
Infecções por Adenoviridae , Aviadenovirus , Hepatite , Doenças das Aves Domésticas , Animais , Galinhas , Infecções por Adenoviridae/prevenção & controle , Infecções por Adenoviridae/veterinária , Vacinas Sintéticas , Corpos de Inclusão , Vacinação/veterinária , Sorogrupo
13.
Front Immunol ; 14: 1185232, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37261344

RESUMO

The present study investigated the expression of cytokines and cellular changes in chickens following vaccination with irradiated avian pathogenic Escherichia coli (APEC) and/or challenge. Four groups of 11-week-old pullets, each consisting of 16 birds were kept separately in isolators before they were sham inoculated (N), challenged only (C), vaccinated (V) or vaccinated and challenged (V+C). Vaccination was performed using irradiated APEC applied via aerosol. For challenge, the homologous strain was administered intratracheally. Birds were sacrificed on 3, 7, 14 and 21 days post challenge (dpc) to examine lesions, organ to body weight ratios and bacterial colonization. Lung and spleen were sampled for investigating gene expression of cytokines mediating inflammation by RT-qPCR and changes in the phenotype of subsets of mononuclear cells by flow cytometry. After re-stimulation of immune cells by co-cultivation with the pathogen, APEC-specific IFN-γ producing cells were determined. Challenged only birds showed more severe pathological and histopathological lesions, a higher probability of bacterial re-isolation and higher organ to body weight ratios compared to vaccinated and challenged birds. In the lung, an upregulation of IL-1ß and IL-6 following vaccination and/or challenge at 3 dpc was observed, whereas in the spleen IL-1ß was elevated. Changes were observed in macrophages and TCR-γδ+ cells within 7 dpc in spleen and lung of challenged birds. Furthermore, an increase of CD4+ cells in spleen and a rise of Bu-1+ cells in lung were present in vaccinated and challenged birds at 3 dpc. APEC re-stimulated lung and spleen mononuclear cells from only challenged pullets showed a significant increase of IFN-γ+CD8α+ and IFN-γ+TCR-γδ+ cells. Vaccinated and challenged chickens responded with a significant increase of IFN-γ+CD8α+ T cells in the lung and IFN-γ+TCR-γδ+ cells in the spleen. Re-stimulation of lung mononuclear cells from vaccinated birds resulted in a significant increase of both IFN-γ+CD8α+ and IFN-γ+TCR-γδ+ cells. In conclusion, vaccination with irradiated APEC caused enhanced pro-inflammatory response as well as the production of APEC-specific IFN-γ-producing γδ and CD8α T cells, which underlines the immunostimulatory effect of the vaccine in the lung. Hence, our study provides insights into the underlying immune mechanisms that account for the defense against APEC.


Assuntos
Infecções por Escherichia coli , Vacinas contra Escherichia coli , Animais , Galinhas , Feminino , Vacinas contra Escherichia coli/administração & dosagem , Vacinas contra Escherichia coli/imunologia , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/veterinária , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/prevenção & controle , Aerossóis
14.
Respir Care ; 68(7): 998-1012, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37353334

RESUMO

Long-term oxygen therapy (LTOT) is a mainstay treatment for patients with severe resting hypoxemia secondary to chronic respiratory conditions including COPD. The evidence for LTOT is based on two trials that are now several decades old but have been insufficiently revisited. Therefore, many questions remain about precisely which patients experience the most benefit from LTOT, as well as how to define that benefit. Most studies have examined LTOT's effect on longevity rather than its impact on quality of life. In addition, many challenges exist in training both clinicians and patients on best practices for LTOT and associated equipment. Reimbursement policies have reduced the kinds of equipment available to the LTOT patient community, presenting additional challenges. This paper will review the current evidence for LTOT in COPD, the challenges involved with providing optimal therapy, and potential avenues of modernizing this essential intervention.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/complicações , Doença Pulmonar Obstrutiva Crônica/terapia , Qualidade de Vida , Oxigenoterapia , Hipóxia/etiologia , Hipóxia/terapia , Oxigênio
15.
Microbiol Spectr ; 11(3): e0010623, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37166309

RESUMO

In numerous countries, strict and targeted measures concerning Salmonella monitoring and control are implemented and high quality of surveillance is ensured by obligatory investigation of samples from the primary production level of animals according to EN/ISO standards. Here, 2 phenotypic characteristics of Salmonella exhibited on compulsory media are crucial, namely, motility demonstrated on modified semisolid Rappaport Vassiliadis agar (MSRV), and production of hydrogen sulfide (H2S) on xylose lysine deoxycholate agar (XLD). In the present study, we describe the detection of Salmonella Infantis variants found in broiler environmental samples with major alterations in their growth characteristics on MSRV, XLD, and brilliant green-phenol red-agar (BPLS). The variants proved to be non-motile on MSRV and displayed non-confirming colony appearances on the previously mentioned selective agars. The growth spectrum comprised pinhead sized yellow colonies with small black centers, but also pinpoint sized colorless colonies, both colony types of regular shape. Our work contributes to highlight the finding of S. Infantis variants which possess more than one phenotypic deviation from the "typical" growth characteristics and by this limit the detection power of the actual obligatory used media. IMPORTANCE Salmonellosis caused by non-typhoidal Salmonella serovars is the second most frequently reported zoonotic disease in humans in the EU. The transmission of these agents is mainly via contaminated food of animal origin. In this context, poultry products are the main source of infection. Therefore, continuous and standardized surveillance of the prevalence of such Salmonella serovars at the primary production level is essential. Our findings show the phenotypic heterogeneity of the serovar Infantis and provide growth characteristics of atypical variants. Such variants pass unnoticed official screening methods, resulting in incorrect identification and being underrepresented in epidemiological surveillance programs.


Assuntos
Galinhas , Microbiologia de Alimentos , Animais , Humanos , Ágar , Salmonella/genética , Meios de Cultura , Sorogrupo
16.
Pathogens ; 12(3)2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36986380

RESUMO

Entomopathogenic bacteria are obligate symbionts of entomopathogenic nematode (EPN) species. These bacteria biosynthesize and release non-ribosomal-templated hybrid peptides (NR-AMPs), with strong, and large-spectral antimicrobial potential, capable of inactivating pathogens belonging to different prokaryote, and eukaryote taxa. The cell-free conditioned culture media (CFCM) of Xenorhabdus budapestensis and X. szentirmaii efficiently inactivate poultry pathogens like Clostridium, Histomonas, and Eimeria. To learn whether a bio-preparation containing antimicrobial peptides of Xenorhabdus origin with accompanying (in vitro detectable) cytotoxic effects could be considered a safely applicable preventive feed supplement, we conducted a 42-day feeding experiment on freshly hatched broiler cockerels. XENOFOOD (containing autoclaved X. budapestensis, and X. szentirmaii cultures developed on chicken food) were consumed by the birds. The XENOFOOD exerted detectable gastrointestinal (GI) activity (reducing the numbers of the colony-forming Clostridium perfringens units in the lower jejunum. No animal was lost in the experiment. Neither the body weight, growth rate, feed-conversion ratio, nor organ-weight data differed between the control (C) and treated (T) groups, indicating that the XENOFOOD diet did not result in any detectable adverse effects. We suppose that the parameters indicating a moderate enlargement of bursas of Fabricius (average weight, size, and individual bursa/spleen weight-ratios) in the XENOFOOD-fed group must be an indirect indication that the bursa-controlled humoral immune system neutralized the cytotoxic ingredients of the XENOFOOD in the blood, not allowing to reach their critical cytotoxic concentration in the sensitive tissues.

17.
iScience ; 26(3): 106291, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36936784

RESUMO

Nematocysts are generated by secretion of proteins into a post-Golgi compartment. They consist of a capsule that elongates into a long tube, which is coiled inside the capsule matrix and expelled during its nano-second discharge deployed for prey capture. The driving force for discharge is an extreme osmotic pressure of 150 bar. The complex processes of tube elongation and invagination under these biomechanical constraints have so far been elusive. Here, we show that a non-muscle myosin II homolog (HyNMII) is essential for nematocyst formation in Hydra. In early nematocysts, HyNMII assembles to a collar around the neck of the protruding tube. HyNMII then facilitates tube outgrowth by compressing it along the longitudinal axis as evidenced by inhibitor treatment and genetic knockdown. In addition, live imaging of a NOWA::NOWA-GFP transgenic line, which re-defined NOWA as a tube component facilitating invagination, allowed us to analyze the impact of HyNMII on tube maturation.

18.
Mol Metab ; 71: 101705, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36907508

RESUMO

OBJECTIVE: In brown adipose tissue (iBAT), the balance between lipid/glucose uptake and lipolysis is tightly regulated by insulin signaling. Downstream of the insulin receptor, PDK1 and mTORC2 phosphorylate AKT, which activates glucose uptake and lysosomal mTORC1 signaling. The latter requires the late endosomal/lysosomal adaptor and MAPK and mTOR activator (LAMTOR/Ragulator) complex, which serves to translate the nutrient status of the cell to the respective kinase. However, the role of LAMTOR in metabolically active iBAT has been elusive. METHODS: Using an AdipoqCRE-transgenic mouse line, we deleted LAMTOR2 (and thereby the entire LAMTOR complex) in adipose tissue (LT2 AKO). To examine the metabolic consequences, we performed metabolic and biochemical studies in iBAT isolated from mice housed at different temperatures (30 °C, room temperature and 5 °C), after insulin treatment, or in fasted and refed condition. For mechanistic studies, mouse embryonic fibroblasts (MEFs) lacking LAMTOR 2 were analyzed. RESULTS: Deletion of the LAMTOR complex in mouse adipocytes resulted in insulin-independent AKT hyperphosphorylation in iBAT, causing increased glucose and fatty acid uptake, which led to massively enlarged lipid droplets. As LAMTOR2 was essential for the upregulation of de novo lipogenesis, LAMTOR2 deficiency triggered exogenous glucose storage as glycogen in iBAT. These effects are cell autonomous, since AKT hyperphosphorylation was abrogated by PI3K inhibition or by deletion of the mTORC2 component Rictor in LAMTOR2-deficient MEFs. CONCLUSIONS: We identified a homeostatic circuit for the maintenance of iBAT metabolism that links the LAMTOR-mTORC1 pathway to PI3K-mTORC2-AKT signaling downstream of the insulin receptor.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Receptor de Insulina , Camundongos , Animais , Receptor de Insulina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Tecido Adiposo Marrom/metabolismo , Fibroblastos/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Insulina/metabolismo , Camundongos Transgênicos , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Nutrientes , Homeostase , Glucose/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas/metabolismo
19.
Elife ; 122023 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-36661306

RESUMO

Epithelial polarization and polarized cargo transport are highly coordinated and interdependent processes. In our search for novel regulators of epithelial polarization and protein secretion, we used a genome-wide CRISPR/Cas9 screen and combined it with an assay based on fluorescence-activated cell sorting (FACS) to measure the secretion of the apical brush-border hydrolase dipeptidyl peptidase 4 (DPP4). In this way, we performed the first CRISPR screen to date in human polarized epithelial cells. Using high-resolution microscopy, we detected polarization defects and mislocalization of DPP4 to late endosomes/lysosomes after knockout of TM9SF4, anoctamin 8, and ARHGAP33, confirming the identification of novel factors for epithelial polarization and apical cargo secretion. Thus, we provide a powerful tool suitable for studying polarization and cargo secretion in epithelial cells. In addition, we provide a dataset that serves as a resource for the study of novel mechanisms for epithelial polarization and polarized transport and facilitates the investigation of novel congenital diseases associated with these processes.


Assuntos
Dipeptidil Peptidase 4 , Células Epiteliais , Humanos , Dipeptidil Peptidase 4/metabolismo , Células Epiteliais/metabolismo , Intestinos , Microvilosidades/metabolismo , Transporte Proteico , Polaridade Celular , Proteínas de Membrana/metabolismo
20.
Vaccine ; 41(7): 1342-1353, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36642629

RESUMO

Escherichia coli causes colibacillosis in chickens, which has severe economic and public health consequences. For the first time, we investigated the efficacy of gamma-irradiated E. coli to prevent colibacillosis in chickens considering different strains and application routes. Electron microscopy, alamarBlue assay and matrix assisted laser desorption/ionization time-of- flight mass spectrometry showed that the cellular structure, metabolic activity and protein profiles of irradiated and non-treated E. coli PA14/17480/5-ovary (serotype O1:K1) were similar. Subsequently, three animal trials were performed using the irradiated E. coli and clinical signs, pathological lesions and bacterial colonization in systemic organs were assessed. In the first animal trial, the irradiated E. coli PA14/17480/5-ovary administered at 7 and 21 days of age via aerosol and oculonasal routes, respectively, prevented the occurrence of lesions and systemic bacterial spread after homologous challenge, as efficient as live infection or formalin-killed cells. In the second trial, a single aerosol application of the same irradiated strain in one-day old chickens was efficacious against challenges with a homologous or a heterologous strain (undefined serotype). The aerosol application elicited better protection as compared to oculonasal route. Finally, in the third trial, efficacy against E. coli PA15/19103-3 (serotype O78:K80) was shown. Additionally, previous results of homologous protection were reconfirmed. The irradiated PA15/19103-3 strain, which also showed lower metabolic activity, was less preferred even for the homologous protection, underlining the importance of the vaccine strain. In all the trials, the irradiated E. coli did not provoke antibody response indicating the importance of innate or cell mediated immunity for protection. In conclusion, this proof-of-concept study showed that the non-adjuvanted single aerosol application of irradiated "killed but metabolically active" E. coli provided promising results to prevent colibacillosis in chickens at an early stage of life. The findings open new avenues for vaccine production with E. coli in chickens using irradiation technology.


Assuntos
Infecções por Escherichia coli , Doenças das Aves Domésticas , Animais , Escherichia coli , Galinhas , Sorogrupo , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/veterinária
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