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1.
Mol Biol Cell ; 34(1): br1, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36350697

RESUMO

Dynein inactivates the spindle assembly checkpoint (SAC) by transporting checkpoint proteins away from kinetochores toward spindle poles in a process known as "stripping." We find that inhibition of Aurora A kinase, which is localized to spindle poles, enables the accumulation of the spindle checkpoint activator Mad1 at poles where it is normally absent. Aurora kinases phosphorylate the dynein activator NudE neurodevelopment protein 1 like 1 (Ndel1) on Ser285 and Mad1 accumulates at poles when Ndel1 is replaced by a nonphosphorylatable mutant in human cells. The pole focusing protein NuMA, transported to poles by dynein, also accumulates at poles in cells harboring a mutant Ndel1. Phosphorylation of Ndel1 on Ser285 is required for robust spindle checkpoint activity and regulates the poles of asters in Xenopus extracts. Our data suggest that dynein/SAC complexes that are generated at kinetochores and then transported directionally toward poles on microtubules are inhibited by Aurora A before they reach spindle poles. These data suggest that Aurora A generates a spatial signal at spindle poles that controls dynein transport and spindle function.


Assuntos
Dineínas , Fuso Acromático , Humanos , Dineínas/metabolismo , Fuso Acromático/metabolismo , Aurora Quinase A/metabolismo , Cinetocoros/metabolismo , Proteínas de Ciclo Celular/metabolismo , Polos do Fuso/metabolismo , Microtúbulos/metabolismo , Proteínas de Transporte/metabolismo
2.
Proc Natl Acad Sci U S A ; 119(24): e2118048119, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-37146302

RESUMO

Rhabdomyosarcoma (RMS) is one of the most common pediatric soft-tissue cancer. Previously, we discovered a gene fusion, MARS-AVIL formed by chromosomal inversion in RMS. Suspecting that forming a fusion with a housekeeping gene may be one of the mechanisms to dysregulate an oncogene, we investigated AVIL expression and its role in RMS. We first showed that MARS-AVIL translates into an in-frame fusion protein, which is critical for RMS cell tumorigenesis. Besides forming a gene fusion with the housekeeping gene, MARS, the AVIL locus is often amplified, and its RNA and protein expression are overexpressed in the majority of RMSs. Tumors with AVIL dysregulation exhibit evidence of oncogene addiction: Silencing MARS-AVIL in cells harboring the fusion, or silencing AVIL in cells with AVIL overexpression, nearly eradicated the cells in culture, as well as inhibited in vivo xenograft growth in mice. Conversely, gain-of-function manipulations of AVIL led to increased cell growth and migration, enhanced foci formation in mouse fibroblasts, and most importantly transformed mesenchymal stem cells in vitro and in vivo. Mechanistically, AVIL seems to serve as a converging node functioning upstream of two oncogenic pathways, PAX3-FOXO1 and RAS, thus connecting two types of RMS associated with these pathways. Interestingly, AVIL is overexpressed in other sarcoma cells as well, and its expression correlates with clinical outcomes, with higher levels of AVIL expression being associated with worse prognosis. AVIL is a bona fide oncogene in RMS, and RMS cells are addicted to its activity.


Assuntos
Rabdomiossarcoma Alveolar , Rabdomiossarcoma , Humanos , Animais , Camundongos , Fatores de Transcrição Box Pareados/metabolismo , Linhagem Celular Tumoral , Rabdomiossarcoma/genética , Rabdomiossarcoma/patologia , Oncogenes/genética , Feniramina , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Regulação Neoplásica da Expressão Gênica , Rabdomiossarcoma Alveolar/genética , Proteínas dos Microfilamentos/metabolismo
3.
Nat Commun ; 11(1): 3457, 2020 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-32651364

RESUMO

Glioblastoma is a deadly cancer, with no effective therapies. Better understanding and identification of selective targets are urgently needed. We found that advillin (AVIL) is overexpressed in all the glioblastomas we tested including glioblastoma stem/initiating cells, but hardly detectable in non-neoplastic astrocytes, neural stem cells or normal brain. Glioma patients with increased AVIL expression have a worse prognosis. Silencing AVIL nearly eradicated glioblastoma cells in culture, and dramatically inhibited in vivo xenografts in mice, but had no effect on normal control cells. Conversely, overexpressing AVIL promoted cell proliferation and migration, enabled fibroblasts to escape contact inhibition, and transformed immortalized astrocytes, supporting AVIL being a bona fide oncogene. We provide evidence that the tumorigenic effect of AVIL is partly mediated by FOXM1, which regulates LIN28B, whose expression also correlates with clinical prognosis. AVIL regulates the cytoskeleton through modulating F-actin, while mutants disrupting F-actin binding are defective in its tumorigenic capabilities.


Assuntos
Glioblastoma/metabolismo , Glioblastoma/patologia , Proteínas dos Microfilamentos/metabolismo , Animais , Western Blotting , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Movimento Celular/fisiologia , Proliferação de Células/genética , Proliferação de Células/fisiologia , Citoesqueleto/metabolismo , Imunofluorescência , Glioblastoma/genética , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteínas dos Microfilamentos/genética , Microscopia Confocal , Reação em Cadeia da Polimerase em Tempo Real
4.
PLoS One ; 12(10): e0186177, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29020103

RESUMO

The aim of this study was to measure the area of the coronary ostia, assess their localization in the coronary sinuses and to determine the morphology of the stem of the left and right coronary arteries in the domestic shorthair cat. The study was conducted on 100 hearts of domestic shorthair cats of both sexes, aged 2-18 years, with an average body weight of 4.05 kg. A morphometric analysis of the coronary ostia was carried out on 52 hearts. The remaining 48 hearts were injected with a casting material in order to carry out a morphological assessment of the left and right coronary arteries. In all the studied animals, the surface of the left coronary artery ostium was larger than the surface of the right coronary artery ostium. There were four types of the left main coronary artery: type I (23 animals, 49%)-double-branched left main stem (giving off the left circumflex branch and the interventricular paraconal branch, which in turn gave off the septal branch), type II (12 animals, 26%)-double-branched left main stem (giving off the left circumflex branch and the interventricular paraconal branch without the septal branch), type III (11 animals, 23%)-triple-branched left main stem (giving off the left circumflex branch, interventricular branch and the septal branch, type IV (1 animal, 2%)-double-branched left main stem (giving off the interventricular paraconal branch and the left circumflex branch, which in turn gave off the septal branch). The left coronary artery ostium is greater than the right one. There is considerable diversity in the branches of proximal segment of the left coronary artery, while the right coronary artery is more conservative. These results can be useful in defining the optimal strategies in the endovascular procedures involving the coronary arteries or the aortic valve in the domestic shorthair cat.


Assuntos
Animais Domésticos/anatomia & histologia , Seio Coronário/anatomia & histologia , Vasos Coronários/anatomia & histologia , Animais , Aorta/anatomia & histologia , Valva Aórtica/anatomia & histologia , Gatos , Feminino , Masculino
5.
Dev Cell ; 41(4): 438-449.e4, 2017 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-28535377

RESUMO

Yeast use the ring-shaped Dam1 complex to slide down depolymerizing microtubules to move chromosomes, but current models suggest that other eukaryotes do not have a sliding ring. We visualized Ndc80 and Ska complexes on microtubules by electron microscopic tomography to identify the structure of the human kinetochore-microtubule attachment. Ndc80 recruits the Ska complex so that the V shape of the Ska dimer interacts along protofilaments. We identify a mutant of the Ndc80 tail that is deficient in Ska recruitment to kinetochores and in orienting Ska along protofilaments in vitro. This mutant Ndc80 binds microtubules with normal affinity but is deficient in clustering along protofilaments. We propose that Ska is recruited to kinetochores by clusters of Ndc80 proteins and that our structure of Ndc80 and Ska complexes on microtubules suggests a mechanism for metazoan kinetochores to couple the depolymerization of microtubules to power the movement of chromosomes.


Assuntos
Cinetocoros/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas Nucleares/metabolismo , Aurora Quinases/metabolismo , Proteínas do Citoesqueleto , Células HeLa , Humanos , Cinetocoros/ultraestrutura , Metáfase , Microtúbulos/metabolismo , Microtúbulos/ultraestrutura , Modelos Biológicos , Modelos Moleculares , Proteínas Nucleares/química , Mutação Puntual/genética , Domínios Proteicos , Fuso Acromático/metabolismo
6.
Elife ; 52016 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-26981768

RESUMO

The spindle- and kinetochore-associated (Ska) complex is essential for normal anaphase onset in mitosis. The C-terminal domain (CTD) of Ska1 binds microtubules and was proposed to facilitate kinetochore movement on depolymerizing spindle microtubules. Here, we show that Ska complex recruits protein phosphatase 1 (PP1) to kinetochores. This recruitment requires the Ska1 CTD, which binds PP1 in vitro and in human HeLa cells. Ska1 lacking its CTD fused to a PP1-binding peptide or fused directly to PP1 rescues mitotic defects caused by Ska1 depletion. Ska1 fusion to catalytically dead PP1 mutant does not rescue and shows dominant negative effects. Thus, the Ska complex, specifically the Ska1 CTD, recruits PP1 to kinetochores to oppose spindle checkpoint signaling kinases and promote anaphase onset. Microtubule binding by Ska, rather than acting in force production for chromosome movement, may instead serve to promote PP1 recruitment to kinetochores fully attached to spindle microtubules at metaphase.


Assuntos
Anáfase , Proteínas Cromossômicas não Histona/metabolismo , Cinetocoros/metabolismo , Metáfase , Proteína Fosfatase 1/metabolismo , Células HeLa , Humanos , Domínios Proteicos
7.
Curr Microbiol ; 71(3): 373-81, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26134536

RESUMO

Kazachstania slooffiae is the dominating yeast in pig's gut. No methods others than cultivation were applied for enumeration of yeasts within this ecosystem. Therefore, the aim of this study was to develop a real-time quantitative polymerase chain reaction (qPCR) assay to quantitate total yeasts and K. slooffiae in the porcine gut. This work demonstrated that the copy numbers in gDNA can be determined by qPCR using PCR amplicons as a calibrator and one-point calibration method. The gDNA were then used as a calibrator for further analysis. The values of quantitation cycle and PCR amplification efficiency of gDNA calibrator were highly reproducible. DNA was extracted from feces and from 10 different cultured yeasts found in pigs' intestine. The qPCR results using primers NL1/LS2 encoding 26S rDNA correlated (r = 0.984, P < 0.0001) with cultivation results. From two primer sets developed, one set encoding act1 gene was suitable for quantitation of K. slooffiae. The copy numbers of K. slooffiae could be determined by 40% analyzed animals, amounting to about 70% of total yeasts. The application of this method in next studies will help to get more information about K. slooffiae and total yeasts in the gut of pigs.


Assuntos
Trato Gastrointestinal/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Saccharomycetales/classificação , Saccharomycetales/isolamento & purificação , Leveduras/classificação , Leveduras/isolamento & purificação , Animais , Primers do DNA/genética , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , RNA Ribossômico/genética , Reprodutibilidade dos Testes , Suínos
8.
Berl Munch Tierarztl Wochenschr ; 128(3-4): 155-62, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25876276

RESUMO

Campylobacter (C.) spp. are well recognised as the leading cause of bacterial food-borne diarrheal disease worldwide, with C. jejuni and C. coli as the most important species: C. coli is highly abundant in pigs and pork meat has often been implicated as a source for human infection. Intestinal colonisation of C. coli in pigs plays a role in carcass contamination during slaughter. Different pre-harvest intervention measures are proposed to reduce the C. coli burden in the porcine intestine. Among others, the use of probiotics to prevent or reduce the colonisation of intestinal pathogens is discussed. One aim of this study was to screen a variety of probiotics to evaluate their inhibitory activity against Campylobacter spp. in vitro. Therefore, cell-free culture supernatants of Lactobacillus spp., Bifidobacterium spp., Enterococcus (E.) faecium NCIMB 10415, and Escherichia coli Nissle 1917 were tested against C. jejuni and C. coli by a well-diffusion agar assay. Seven out of eleven Lactobacillus strains showed an inhibitory activity against at least one of the three tested Campylobacter strains. This antagonistic activity against Campylobacter spp. was caused by the production of organic acids that lowered the pH. Application with pH neutralised cell-free culture supernatants abolished this inhibitory effect. Other tested strains with probiotic properties showed no inhibitory activity against any Campylobacter spp. strain. The strain E. faecium NCIMB 10415 was chosen to test its inhibitory activity against C. coli in vivo. Twenty weaned piglets were allocated into two groups, a probiotic group and a control group.The diet of the probiotic group was supplemented with E. faecium NCIMB 10415 (10(9) cfu/kg feed, Cylactin) since weaning, whereas the control group received no probiotic treatment. All piglets were naturally colonised with C. coli. The excretion load of C. coli was monitored for 28 days. The results indicate that dietary supplementation of E. faecium NCIMB 10415 did not significantly affect C. coli excretion levels in pigs. In this study, E. faecium NCIMB 10415 showed no antagonistic activity against C. coli in vitro and in vivo and had no impact on the growth performance of weaned piglets.


Assuntos
Campylobacter jejuni/efeitos dos fármacos , Probióticos/farmacologia , Animais , Campylobacter jejuni/fisiologia , Contagem de Colônia Microbiana , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/fisiologia , Fezes/microbiologia , Humanos , Interações Microbianas , Testes de Sensibilidade Microbiana , Suínos
9.
Virol J ; 11: 140, 2014 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-25103309

RESUMO

BACKGROUND: Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most important infectious agents for the swine industry worldwide. Zinc (Zn) salts, which are widely used as a dietary supplement in swine nutrition, have shown antiviral effects in vitro as well as in vivo. The purpose of this study was to determine the influence of dietary zinc oxide supplementation on vaccination and challenge infection with PRRSV. FINDINGS: The clinical course of PRRS and the success of vaccination with an experimental inactivated vaccine were compared between animals receiving a conventional diet (50 ppm Zn, control group) and diets supplemented with Zn oxide (ZnO) at final Zn concentrations of 150 or 2,500 ppm. Pigs receiving higher dietary Zn levels showed a tendency towards higher neutralizing antibody levels after infection, while dietary Zn levels did not substantially influence the number of antiviral IFN-gamma secreting cells (IFN-gamma-SC) or percentages of blood immune cell subsets after infection. Finally, feeding higher dietary Zn levels reduced neither clinical symptoms nor viral loads. CONCLUSIONS: Our results suggest that higher levels of dietary ZnO do not have the potential to stimulate or modulate systemic immune responses after vaccination and heterologous PRRSV infection to an extent that could improve the clinical and virological outcome.


Assuntos
Suplementos Nutricionais , Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Óxido de Zinco/administração & dosagem , Animais , Anticorpos Antivirais/imunologia , Temperatura Corporal , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Masculino , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Suínos , Vacinação , Carga Viral , Vacinas Virais/imunologia
10.
Mol Ther ; 22(10): 1730-40, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24985163

RESUMO

New treatment strategies for inflammatory bowel disease are needed and parasitic nematode infections or application of helminth components improve clinical and experimental gut inflammation. We genetically modified the probiotic bacterium Escherichia coli Nissle 1917 to secrete the powerful nematode immunomodulator cystatin in the gut. This treatment was tested in a murine colitis model and on post-weaning intestinal inflammation in pigs, an outbred model with a gastrointestinal system similar to humans. Application of the transgenic probiotic significantly decreased intestinal inflammation in murine acute colitis, associated with increased frequencies of Foxp3(+) Tregs, suppressed local interleukin (IL)-6 and IL-17A production, decreased macrophage inflammatory protein-1α/ß, monocyte chemoattractant protein -1/3, and regulated upon activation, normal T-cell expressed, and secreted expression and fewer inflammatory macrophages in the colon. High dosages of the transgenic probiotic were well tolerated by post-weaning piglets. Despite being recognized by T cells, secreted cystatin did not lead to changes in cytokine expression or macrophage activation in the colon. However, colon transepithelial resistance and barrier function were significantly improved in pigs receiving the transgenic probotic and post-weaning colon inflammation was reduced. Thus, the anti-inflammatory efficiency of a probiotic can be improved by a nematode-derived immunoregulatory transgene. This treatment regimen should be further investigated as a potential therapeutic option for inflammatory bowel disease.


Assuntos
Gastroenterite/terapia , Fatores Imunológicos/biossíntese , Fatores Imunológicos/genética , Probióticos/metabolismo , Probióticos/uso terapêutico , Animais , Quimiocinas/genética , Quimiocinas/metabolismo , Colite/induzido quimicamente , Colite/metabolismo , Colite/patologia , Colite/terapia , Cistatinas/biossíntese , Cistatinas/genética , Cistatinas/imunologia , Modelos Animais de Doenças , Escherichia coli/genética , Escherichia coli/metabolismo , Gastroenterite/imunologia , Gastroenterite/metabolismo , Gastroenterite/parasitologia , Expressão Gênica , Fatores Imunológicos/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Probióticos/administração & dosagem , Probióticos/efeitos adversos , Suínos
11.
BMC Vet Res ; 10: 75, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24673930

RESUMO

BACKGROUND: Zinc (Zn) supplementation has been shown to reduce the incidence of diarrhea and to protect animals from intestinal diseases, but the mechanisms of this protective effect against virus infection in vivo have not yet been elucidated. Transmissible gastroenteritis virus (TGEV) causes diarrhea in piglets with an age-dependent decrease of severity. RESULTS: We used 60 weaned piglets that were divided into three groups to evaluate the effect of different Zn levels added to a conventional diet (50 mg Zn/kg diet, Znlow, control group). The other groups received the diet supplemented with ZnO at final concentrations of 150 mg Zn/kg diet (Znmed), or 2,500 mg/kg diet (Znhigh). Oral challenge infection with TGEV was performed when the pigs had been fed for 1 week with the respective diet. Half of the piglets of each group were sacrificed at day 1 and 18 after challenge infection. Fecal consistency was improved and body weights increased in the Znhigh group when compared to the other groups, but no direct effect of Zn concentrations in the diet on fecal TGEV shedding and mucosal immune responses was detectable. However, in the Znhigh group, we found a prevention of villus atrophy and decreased caspase-3-mediated apoptosis of jejunal epithelium. Furthermore, pigs receiving high Zn diet showed a down-regulation of interferon (IFN)-α, oligoadenylate synthetase (OAS), Zn transporter SLC39A4 (ZIP4), but up-regulation of metallothionein-1 (MT1), as well as the Zn transporters SLC30A1 (ZnT1) and SLC30A5 (ZnT5). In addition, forskolin-induced chloride secretion and epithelial resistance were controlled at a physiological level in the Znhigh but not the other groups. Finally, in the Znhigh group, we documented an earlier and higher systemic TGEV-specific serum antibody response. CONCLUSIONS: These results suggest that high dietary Zn could provide enhanced protection in the intestinal tract and stimulate the systemic humoral immune response against TGEV infection.


Assuntos
Suplementos Nutricionais , Gastroenterite Suína Transmissível/tratamento farmacológico , Vírus da Gastroenterite Transmissível/genética , Óxido de Zinco/farmacologia , Ração Animal , Animais , Caspase 3/metabolismo , Dieta/veterinária , Feminino , Regulação da Expressão Gênica/fisiologia , Mucosa Intestinal/enzimologia , Mucosa Intestinal/metabolismo , Jejuno/enzimologia , Masculino , Suínos , Oligoelementos
12.
PLoS One ; 9(1): e87007, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24489827

RESUMO

Swine influenza viruses (SIV) regularly cause significant disease in pigs worldwide. Since there is no causative treatment of SIV, we tested if probiotic Enterococcus (E.) faecium NCIMB 10415 or zinc (Zn) oxide as feed supplements provide beneficial effects upon SIV infection in piglets. Seventy-two weaned piglets were fed three different diets containing either E. faecium or different levels of Zn (2500 ppm, Zn(high); 50 ppm, Zn(low)). Half of the piglets were vaccinated intramuscularly (VAC) twice with an inactivated trivalent SIV vaccine, while all piglets were then infected intranasally with H3N2 SIV. Significantly higher weekly weight gains were observed in the E. faecium group before virus infection, and piglets in Zn(high) and E. faecium groups gained weight after infection while those in the control group (Zn(low)) lost weight. Using ELISA, we found significantly higher H3N2-specific antibody levels in the E. faecium+VAC group 2 days before and at the day of challenge infection as well as at 4 and 6 days after challenge infection. Higher hemagglutination inhibition (HI) titers were also observed in the Zn(high)+VAC and E. faecium+VAC groups at 0, 1 and 4 days after infection. However, there were no significant differences in virus shedding and lung lesions between the dietary groups. Using flow cytometry analysis significantly higher activated T helper cells and cytotoxic T lymphocyte percentages in the PBMCs were detected in the Zn(high) and E. faecium groups at single time points after infection compared to the Zn(low) control group, but no prolonged effect was found. In the BAL cells no influence of dietary supplementation on immune cell percentages could be detected. Our results suggest that feeding high doses of zinc oxide and particularly E. faecium could beneficially influence humoral immune responses after vaccination and recovery from SIV infection, but not affect virus shedding and lung pathology.


Assuntos
Enterococcus faecium/metabolismo , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Sus scrofa/imunologia , Vacinação , Óxido de Zinco/farmacologia , Animais , Anticorpos Antivirais/imunologia , Contagem de Células Sanguíneas , Temperatura Corporal , Dieta , Cães , Ensaio de Imunoadsorção Enzimática , Testes de Inibição da Hemaglutinação , Imunidade Celular/efeitos dos fármacos , Imunidade Humoral/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/virologia , Células Madin Darby de Rim Canino , Infecções por Orthomyxoviridae/sangue , Infecções por Orthomyxoviridae/patologia , Sus scrofa/virologia , Eliminação de Partículas Virais/efeitos dos fármacos , Aumento de Peso/efeitos dos fármacos
13.
Vet Immunol Immunopathol ; 157(1-2): 65-77, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24246154

RESUMO

In a Salmonella challenge study of weaned piglets supplemented with the probiotic Enterococcus faecium NCIMB 10415 (SF68), we observed a delayed, post-infection proliferative response of purified blood mononuclear cell fractions towards Salmonella antigens. In order to clarify this observation, we examined the patterns of immune-associated gene expression in long-term feeding trials of both pre- and post-weaning piglets. Piglets supplemented with E. faecium NCIMB 10415 showed a post-weaning dysregulation in the expression patterns of both pro- and anti-inflammatory cytokine expression in intestinal tissues and spleen. Piglets of the supplemented group showed significantly reduced levels of IL-8, IL-10 and the co-stimulatory molecule CD86 mRNA expression in ileal Peyer's patches. The expression of CTLA4, an inhibitor of T-cell activation/proliferation, showed similar levels of expression in all tissues examined, particularly in ileal Peyer's patches post-weaning where IL-8, IL-10 and CD86 transcript levels were significantly reduced relative to control animals. Blood serum cytokine protein levels showed elevated TGFß in pre-weaning piglets which, together with IL-6, may have suppressed IFNγ production in the probiotic-fed animals. In a second Salmonella challenge study, post-weaning, E. faecium-fed animals showed significantly elevated levels of IL-8 gene expression in mesenteric lymph nodes, but reduced levels in the spleen. At early times post-infection, the probiotic-fed group showed similar levels of IL-10, CD86 and CTLA4 mRNA expression as the control animals in intestinal Peyer's Patches, despite high relative levels of IL-8 expression in mesenteric lymph nodes. The sum of the observations suggests that supplementation of pre-weaning piglets with E. faecium affects intestinal immune-associated gene expression, which is aggravated post-weaning when the animals receive increased levels of the probiotic in feed. We suggest the post-weaning reductions in gene expression may delay the host response to infections, and provide pathogenic bacteria such as Salmonella with a "window of opportunity", leading to the increased bacterial loads and shedding observed in challenge trials. Possible mechanisms explaining these effects of E. faecium NCIMB 10415 are discussed.


Assuntos
Enterococcus faecium/imunologia , Enteropatias/veterinária , Probióticos/farmacologia , Salmonelose Animal/microbiologia , Salmonella typhimurium/imunologia , Doenças dos Suínos/microbiologia , Animais , Citocinas/sangue , Citocinas/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Perfilação da Expressão Gênica/veterinária , Enteropatias/imunologia , Enteropatias/microbiologia , Enteropatias/prevenção & controle , Gravidez , RNA Bacteriano/química , RNA Bacteriano/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Salmonelose Animal/imunologia , Salmonelose Animal/prevenção & controle , Salmonella typhimurium/genética , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/prevenção & controle
14.
BMC Vet Res ; 9: 64, 2013 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-23557095

RESUMO

BACKGROUND: Recent new anatomical and histological features of craniocervical junction in dogs and cats were described providing evidence of differences between the carnivore species. No information on these structures in foxes exists. RESULTS: Two parts of the alar ligaments were found. A longer one aroused from dens of axis to the internal (medial) surface of the occipital condyles and was called apical part. A shorter part originated from the entire length of the lateral edge of the dens of axis and terminated on the internal wall of the vertebral foramen of atlas and thus was called the lateral part. The transverse ligament of the atlas was widened in the mid region, above the dens of axis, and thickened at enthesis. Periosteal fibrocartilage was detected in the transverse ligament of the atlas at the enthesis, and sesamoid fibrocartilage was present on periphery in the middle of the ligament. CONCLUSIONS: The craniocervical junction in foxes differs in part from other carnivores such as dogs and cats but resembles that of mesaticephalic dogs. The sesamoid and periosteal fibrocartilage supports the transverse ligament of the atlas whereas the alar ligaments have no cartilage.


Assuntos
Atlas Cervical/anatomia & histologia , Raposas/anatomia & histologia , Ligamentos Articulares/anatomia & histologia , Animais , Articulação Atlantoaxial/anatomia & histologia , Articulação Atlantoccipital/anatomia & histologia , Vértebra Cervical Áxis/anatomia & histologia , Cartilagem Articular/anatomia & histologia , Masculino
15.
Appl Environ Microbiol ; 79(9): 2914-21, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23435881

RESUMO

Twenty-eight-day-old weaned pigs were fed diets with a low (LZn), medium (MZn), or high (MZn) Zn concentration (50 to 80, 150, or 2,500 mg Zn/kg of diet, respectively) provided as zinc oxide (ZnO)(24 pigs per group). They were infected orally with Salmonella enterica serovar Typhimurium DT104 on day 32. Salmonellae were cultivated from feces (up to 42 days postinfection [dpi]) and organs (2 and 42 dpi). Activation of the adaptive systemic and mucosal immune systems was investigated by recording anti-Salmonella IgG levels and levels of B and T lymphocyte subpopulations in blood and gut-associated lymphatic tissue. Growth performance was recorded as well. Salmonellae were shed at higher levels and for longer periods in the HZn group (P < 0.05), with no differences in the tissues. At 2 dpi, the relative percentages of CD4(+) T helper cells (P < 0.01) and of CD2(+) T and NK cells (P < 0.01) in blood were reduced from the relative cell counts obtained at 0 dpi, irrespective of the Zn group. The lowest percentage of cytotoxic T cells was found 14 dpi in the HZn group relative to the MZn (P < 0.05) and LZn (P < 0.01) groups. Supplementation of the feed with 2,500 mg Zn/kg of diet immediately after weaning could positively affect the immune responses of piglets infected with Salmonella Typhimurium, but for a short period only. After 2 weeks, all positive effects disappeared, and rather negative effects, such as higher shedding of salmonellae, lower T cell frequencies, and worse performance, occurred. Thus, supplementation with ZnO at high levels in the pig industry should be limited to 2 to 3 weeks.


Assuntos
Salmonelose Animal/prevenção & controle , Salmonella typhimurium/crescimento & desenvolvimento , Doenças dos Suínos/prevenção & controle , Óxido de Zinco/farmacologia , Imunidade Adaptativa/efeitos dos fármacos , Ração Animal , Animais , Anticorpos Antibacterianos/efeitos dos fármacos , Anticorpos Antibacterianos/imunologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Derrame de Bactérias , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Fezes/microbiologia , Feminino , Imunidade Humoral/efeitos dos fármacos , Imunoglobulina G/efeitos dos fármacos , Imunoglobulina G/imunologia , Masculino , Distribuição Aleatória , Salmonelose Animal/imunologia , Salmonelose Animal/microbiologia , Salmonella typhimurium/efeitos dos fármacos , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/microbiologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Fatores de Tempo , Desmame , Óxido de Zinco/administração & dosagem
16.
Vet Microbiol ; 162(1): 136-43, 2013 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-22986057

RESUMO

Campylobacter (C.) is one of the most common food-borne pathogen causing bacterial enteric infections in humans. Consumption of meat and meat products that have been contaminated with Campylobacter are the major source of infection. Pigs are a natural reservoir of Campylobacter spp. with C. coli as the dominant species. Even though some studies focussed on transmission of C. coli in pig herds and the excretion in faeces, little is known about the colonisation and excretion dynamics of C. coli in a complex gut microbiota present in weaned piglets and the translocation to different tissues. Therefore, an experimental trial was conducted to evaluate the colonisation and translocation ability of the porcine strain C. coli 5981 in weaned pigs. Thus, ten 35 days old piglets were intragastrically inoculated with strain C. coli 5981 (7 × 10(7)CFU/animal) encoding resistances against erythromycin and neomycin. Faecal samples were taken and C. coli levels were enumerated over 28 days. All piglets were naturally colonised with C. coli before experimental inoculation, and excretion levels ranged from 10(4) to 10(7)CFU/g faeces. However, no strain showed resistances against the additional antimicrobials used. Excretion of C. coli 5981 was seen for all piglets seven days after inoculation and highest counts were detectable ten days after inoculation with 10(6)CFU/g faeces. Post-mortem, translocation and subsequent invasion of luminal C. coli was observed for gut tissues of the small intestine and for the gut associated lymphatic tissues, such as jejunal mesenteric lymph nodes and tonsils as well as for spleen and gall bladder. In conclusion, this pig colonisation trial offers the opportunity to study C. coli colonisation in weaned piglets using the porcine strain C. coli 5981 without the need for gnotobiotic or specific pathogen-free animals.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter coli/isolamento & purificação , Doenças dos Suínos/microbiologia , Animais , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/transmissão , Campylobacter coli/crescimento & desenvolvimento , Fezes/microbiologia , Células HT29 , Humanos , Intestino Delgado/microbiologia , Carne/microbiologia , Suínos , Doenças dos Suínos/transmissão , Desmame
17.
Appl Environ Microbiol ; 78(14): 4816-25, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22544257

RESUMO

Salmonella enterica serovar Typhimurium DT 104 is the major pathogen for salmonellosis outbreaks in Europe. We tested if the probiotic bacterium Enterococcus faecium NCIMB 10415 can prevent or alleviate salmonellosis. Therefore, piglets of the German Landrace breed that were treated with E. faecium (n = 16) as a feed additive and untreated controls (n = 16) were challenged with S. Typhimurium 10 days after weaning. The presence of salmonellae in feces and selected organs, as well as the immune response, were investigated. Piglets treated with E. faecium gained less weight than control piglets (P = 0.05). The feeding of E. faecium had no effect on the fecal shedding of salmonellae and resulted in a higher abundance of the pathogen in tonsils of all challenged animals. The specific (anti-Salmonella IgG) and nonspecific (haptoglobin) humoral immune responses as well as the cellular immune response (T helper cells, cytotoxic T cells, regulatory T cells, γδ T cells, and B cells) in the lymph nodes, Peyer's patches of different segments of the intestine (jejunal and ileocecal), the ileal papilla, and in the blood were affected in the course of time after infection (P < 0.05) but not by the E. faecium treatment. These results led to the conclusion that E. faecium may not have beneficial effects on the performance of weaned piglets in the case of S. Typhimurium infection. Therefore, we suggest a critical discussion and reconsideration of E. faecium NCIMB 10415 administration as a probiotic for pigs.


Assuntos
Enterococcus faecium/crescimento & desenvolvimento , Probióticos/administração & dosagem , Salmonelose Animal/prevenção & controle , Salmonella typhimurium/crescimento & desenvolvimento , Doenças dos Suínos/prevenção & controle , Desmame , Ração Animal , Animais , Fezes/microbiologia , Tonsila Palatina/microbiologia , Probióticos/farmacologia , Salmonelose Animal/imunologia , Salmonelose Animal/microbiologia , Salmonella typhimurium/isolamento & purificação , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/microbiologia , Doenças dos Suínos/terapia
18.
PLoS One ; 7(4): e34631, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22514648

RESUMO

BACKGROUND: Animal faeces comprise a community of many different microorganisms including bacteria and viruses. Only scarce information is available about the diversity of viruses present in the faeces of pigs. Here we describe a protocol, which was optimized for the purification of the total fraction of viral particles from pig faeces. The genomes of the purified DNA and RNA viruses were simultaneously amplified by PCR and subjected to deep sequencing followed by bioinformatic analyses. The efficiency of the method was monitored using a process control consisting of three bacteriophages (T4, M13 and MS2) with different morphology and genome types. Defined amounts of the bacteriophages were added to the sample and their abundance was assessed by quantitative PCR during the preparation procedure. RESULTS: The procedure was applied to a pooled faecal sample of five pigs. From this sample, 69,613 sequence reads were generated. All of the added bacteriophages were identified by sequence analysis of the reads. In total, 7.7% of the reads showed significant sequence identities with published viral sequences. They mainly originated from bacteriophages (73.9%) and mammalian viruses (23.9%); 0.8% of the sequences showed identities to plant viruses. The most abundant detected porcine viruses were kobuvirus, rotavirus C, astrovirus, enterovirus B, sapovirus and picobirnavirus. In addition, sequences with identities to the chimpanzee stool-associated circular ssDNA virus were identified. Whole genome analysis indicates that this virus, tentatively designated as pig stool-associated circular ssDNA virus (PigSCV), represents a novel pig virus. CONCLUSION: The established protocol enables the simultaneous detection of DNA and RNA viruses in pig faeces including the identification of so far unknown viruses. It may be applied in studies investigating aetiology, epidemiology and ecology of diseases. The implemented process control serves as quality control, ensures comparability of the method and may be used for further method optimization.


Assuntos
Vírus de DNA/genética , Fezes/virologia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Vírus de RNA/genética , Animais , Sequência de Bases , Dados de Sequência Molecular , Suínos
19.
Comp Immunol Microbiol Infect Dis ; 35(2): 181-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22277829

RESUMO

To assess the general impact of endemic countries on the re-emergence of brucellosis in non-endemic regions of the European Union, the genetic fingerprints of Brucella melitensis strains imported to Germany were compared to ovine strains from Turkey in a molecular epidemiological study. Genotyping of 66 Brucella strains (based on Multiple Locus of Variable number of tandem repeats Analysis) isolated from German travellers and Turkish immigrants living in Germany revealed epidemiological concordance with 20 sheep isolates originating from Eastern Anatolia, Turkey. In summary, cross-border molecular tracing confirmed brucellosis being a zoonosis of concern for European public health.


Assuntos
Brucella melitensis/genética , Brucelose/epidemiologia , Animais , Brucella melitensis/isolamento & purificação , Brucelose/veterinária , DNA Bacteriano/genética , Europa (Continente)/epidemiologia , Genótipo , Alemanha/epidemiologia , Humanos , Tipagem de Sequências Multilocus , Ovinos/microbiologia , Sequências de Repetição em Tandem , Turquia/epidemiologia
20.
Berl Munch Tierarztl Wochenschr ; 124(5-6): 225-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22059293

RESUMO

Most embalming of cadavers for anatomical dissection in veterinary medicine has used 6-10% formaldehyde resulting in discoloured and rigid specimens. This project produced teaching specimens of sheep, horse and calf cadavers having their musculoskeletal and visceral structures with a natural appearance using a fixation solution with lowered concentrations of formaldehyde (2% and 3%) together with ethanol and polyethylene glycols. Fixation parameters (palpable consistency, flexibility, colour, tissue hydration and odour) were assessed qualitatively by twice weekly dissections over two months for sheep and three months for horses and calf. Formaldehyde levels, measured in the breathing zone, were below the maximum allowable concentration in all specimens except for a 300 kg horse cadaver. To evaluate the effectiveness of the fixation solution in microbial inhibition, tissue samples were taken and analyzed for the presence of culturable aerobic and anaerobic bacteria, yeasts and moulds. Single colonies of Pseudomonas oryzihabitans, Chryseobacterium sp., Acinetobacter sp. were isolated from lungs, and Micrococcus sp. and Bacillus sp. were isolated from one muscle sample.


Assuntos
Animais Domésticos , Embalsamamento/métodos , Etanol , Fixadores , Formaldeído , Polietilenoglicóis , Anatomia Veterinária/educação , Animais , Cadáver , Dissecação/normas , Educação em Veterinária , Embalsamamento/normas , Projetos Piloto
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