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1.
J Comp Pathol ; 174: 120-139, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31955797

RESUMO

This study describes the pathomorphological alterations of bovine tuberculosis through gross and histopathological examinations, assessment of the distribution of lesions and the demonstration of mycobacteria. Samples from lungs, liver, small intestine, their regional lymph nodes and retropharyngeal lymph nodes were collected from 84 cattle with tuberculosis from the Allgäu, Germany. Organs were evaluated grossly, histopathologically and by transmission electron microscopy. Mycobacteria and mycobacterial antigens were demonstrated using acid-fast staining and immunohistochemistry (IHC). Bacteriological tests revealed Mycobacterium caprae in all animals. Gross alterations were classified into five patterns (I to V) with an additional pattern of acute exudative pulmonary inflammation (pattern VI). Histological lesions were classified into four types (1-4) with additional lesions occurring in lungs only. Acid-fast staining revealed a low number of bacteria in all tissues, while IHC showed comparatively more mycobacterial antigens within the lesions and also at their periphery. The alimentary tract (68%) was the main portal of entry followed by an aerosol infection (19%). It was assumed that the observed lesions reflect a continuous primary period of infection; there were no lesions typical of a secondary (post-primary) period, as reported in man and also described in the older literature on bovine tuberculosis. The broad spectrum of changes described formerly was not observed in the present cases and the route of infection and nature of acid fast staining showed differences when compared with previous studies of naturally-occurring bovine tuberculosis.


Assuntos
Doenças dos Bovinos/patologia , Tuberculose/veterinária , Animais , Bovinos , Tuberculose/patologia
2.
J Small Anim Pract ; 61(1): 42-45, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31313312

RESUMO

OBJECTIVES: To evaluate matrix-assisted laser desorption ionisation time of flight mass spectrometry (MALDI-TOF MS) combined with the Sepsityper kit (Bruker Daltoniks GmbH, Bremen) for the direct detection of bacterial species from inoculated blood cultures from dogs and cats. MATERIALS AND METHODS: Canine and feline blood samples were inoculated with typical sepsis-causing bacteria such as Staphylococcus intermedius, Staphylococcus aureus, Streptococcus canis, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa at two distinct concentrations (each in triplicate), resulting in 72 blood culture bottles incubated at 37°C. Samples were comparatively analysed with MALDI-TOF MS after preparation with the Sepsityper kit and also by standard bacteriology (culturing and biochemical characterisation). RESULTS: Bacterial species identified from agar plates and by MALDI-TOF MS from blood culture bottles were identical for all samples. The MALDI Biotyper software (Bruker Daltoniks) correctly identified all bacterial strains from inoculated canine and feline blood with analysis indicating very good precision. CLINICAL SIGNIFICANCE: MALDI-TOF MS analysis combined with the Sepsityper kit is a reliable tool for a quick detection of veterinary-relevant bacterial species directly from blood culture bottles. This approach could reduce the time for identification of critical species to only 24 hours.


Assuntos
Doenças do Gato , Doenças do Cão , Sepse/veterinária , Aceleração , Animais , Bactérias , Técnicas Bacteriológicas/veterinária , Gatos , Cães , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/veterinária , Streptococcus
3.
Sci Rep ; 8(1): 9048, 2018 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-29899349

RESUMO

We report the formation of Bi clusters in Ga(P1-x,Bix) layers during an in situ (scanning) transmission electron microscopy ((S)TEM) annealing investigation. The non-destructive temperature regime in dependence on the tertiarybutylphosphine (TBP) pressure in the in situ cell was investigated to ensure that the results are not distorted by any destructive behaviour of the crystal during the thermal treatment. The following annealing series of the Ga(P92.6Bi7.4) and Ga(P96.4Bi3.6) layers reveals that the threshold temperature at which the Bi clustering takes place is 600 °C in the Ga(P92.6Bi7.4) layer. Further thermal treatments up to 750 °C show a relationship between the Bi fraction in the Ga(P1-x,Bix) layer and the initial temperature at which the Bi clustering takes place. Finally, we investigate one Bi cluster at atomic resolution conditions. In these conditions, we found that the Bi cluster crystallized in a rhombohedral phase, aligning with its {101} planes parallel to the Ga(P,Bi) {202} planes.

4.
Trop Biomed ; 35(2): 321-329, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33601806

RESUMO

This study aimed first to estimate the prevalence of subclinical mastitis (SCM) among dairy cows and buffaloes of smallholders who sell milk directly to consumers through bulk tanks of milk distributors. The second aim is to estimate the prevalence of Escherichia coli in milk of SCM cases and identify its virulence genes and to emphasize the public health risk form drinking this milk. A total of 227 and 174 dairy cows and buffaloes, respectively from Kafrelsheikh Governorate, Egypt were examined with California Mastitis Test (CMT) to estimate the prevalence of SCM. Samples were also screened for E. coli using classical bacteriological and molecular methods. The prevalence of CMT-positive cows and buffaloes samples examined was 47.4% (49.9% and 44.3% for cows and buffaloes, respectively). Cows were found to be at a higher risk of getting high CMT score than buffaloes. E. coli was detected bacteriologically in 16.4% and in 27.2% of the CMT-positive cows and buffalo samples, respectively. A total of 83.1% and 75.6% of isolates were confirmed as E. coli using PCR technique. A multiplex PCR assay was used to identify five virulence genes in the E. coli isolates; the eae gene for enteropathogenic E. coli, stx for Shiga toxin-producing E. coli, elt and est for enterotoxigenic E. coli, and the hlyA of the enterohemolysin gene for enterohemorrhagic E. coli. Only one E. coli strain identified carried two virulence genes (eae and est). The high prevalence of SCM among dairy cows and buffaloes in the study area indicated that there is high risk to consumers who consume milk of these animals. Also, control of SCM is a prerequisite among smallholders in Egypt in order to minimize its deleterious effects such as microbial antibiotic resistance and public health hazards. To our knowledge, this is the first study that highlights the ecology of virulence by E. coli causing SCM in Kafrelsheikh governorate, Egypt. This study offers the basis for further phenotypic and molecular characterization of E. coli found in raw milk in order to guarantee safe consumption of raw milk and milk products.

6.
Vet Res Commun ; 41(2): 113-128, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28194548

RESUMO

Single nucleotide polymorphisms (SNPs) calculated from whole genome sequencing (WGS) are ideally suited to study evolutionary relationships of pathogens and their epidemiology. Mycobacterium caprae infections have been documented frequently in cattle and red deer along the Bavarian and Austrian Alps during the last decade. However, little is still known about the transmission within cattle holdings and possible alterations of the genomes of M. caprae during such events. The aim of this study was to study the molecular epidemiology of bovine tuberculosis (bTB) in selected herds based on isolate-specific genome-wide SNPs and to perform a phylogenetic network analysis. In total, 61 M. caprae isolates were collected originating from eight cattle farms over a period of twelve years between 2004 and 2015. Analysis of their sequence data revealed that the M. caprae isolates of an affected farm differ at all in a few SNPs. In contrast, many more SNPs were found when comparing the M. caprae genomes originating from different herds. The results demonstrated that the spread of bTB in the affected farms occurred by direct transmission between the members of each herd rather than between herds and a M. caprae introduction in farms after contact events e. g. on summer pastures can readily be traced by WGS analysis. Furthermore, we assembled a nearly complete whole genome sequence of M. caprae derived from several cattle isolates originating from bTB cases in the Bavarian Alpine region.


Assuntos
Genoma Bacteriano/genética , Mycobacterium/genética , Tuberculose Bovina/transmissão , Animais , Bovinos , DNA Bacteriano/genética , Alemanha/epidemiologia , Reação em Cadeia da Polimerase Multiplex/veterinária , Mycobacterium/patogenicidade , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Tuberculose Bovina/epidemiologia , Tuberculose Bovina/microbiologia
7.
Transbound Emerg Dis ; 64(3): 782-792, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26518998

RESUMO

Alpine Mycobacterium caprae isolates found in cattle and red deer display at least three genetic variations in the region of difference four (RD4) that can be used for further differentiation of the isolates into the subtypes 'Allgäu', 'Karwendel' and 'Lechtal'. Each genomic subtype is thereby characterized by a specific nucleotide deletion pattern in the 12.7-kb RD4 region. Even though M. caprae infections are frequently documented in cattle and red deer, little is known about the transmission routes. Hence, robust markers for M. caprae subtyping are needed to gain insight into the molecular epidemiology. For this reason, a rapid and robust multiplex PCR was developed for the simultaneous detection of three M. caprae RD4 subtypes and was used to subtype a total number of 241 M. caprae isolates from animals (145 cattle, 95 red deer and one fox) from Bavaria and Austria. All three subtypes occur spatially distributed and are found in cattle and in red deer suggesting transmission between the two species. As subtypes are genetically stable in both species it is hypothesized that the described genetic variations developed within the host due to 'within-host replication'. The results of this study recommend the genomic RD4 region as a reliable diagnostic marker for M. caprae subtype differentiation.


Assuntos
Cervos/microbiologia , Raposas/microbiologia , Variação Genética , Infecções por Mycobacterium/veterinária , Mycobacterium/classificação , Mycobacterium/genética , Animais , Áustria/epidemiologia , Bovinos , Marcadores Genéticos , Genômica , Alemanha/epidemiologia , Epidemiologia Molecular , Infecções por Mycobacterium/epidemiologia , Infecções por Mycobacterium/microbiologia
9.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-27004451

RESUMO

OBJECTIVE: Bernese Mountain Dogs (BMD) have a higher prevalence of Borrelia burgdorferi sensu lato (Bbsl) antibodies than other breeds, but it is not known whether this is the case for other pathogens. Therefore, the aim of the study was to determine the frequency and level of specific antibodies against members of the Bbsl group, Anaplasma phagocytophilum (Ap), and Leptospira (L.) interrogans serovars in BMD and compare the results with those found in dogs of other breeds. MATERIALS AND METHODS: A total of 171 healthy BMD and 57 healthy control dogs of other breeds were included in the study. Controls were large dogs (> 30 kg) with long, dark hair coats. A two-tiered testing method consisting of computerized kinetic enzyme-linked immunosorbent assay (KELA) and Western blotting was used for detection of antibodies against Bbsl, an immunofluorescence assay (IFA) was used for detection of antibodies against Ap, and microscopic agglutination test (MAT) for antibodies to 18 different serovars of L. interrogans. RESULTS: The prevalence of anti-Bbsl antibodies was significantly higher in BMD (43.3%) than in controls (17.5%) (p < 0.001). Antibodies to Bbsl attributable to vaccination were excluded from the calculation of prevalence. Antibodies to Ap were found in 50.3% of BMD, whereas only 24.6% of the controls dogs were tested positive for Ap (p < 0.001). Antibody titers of the 18 different serovars of L. interrogans antibodies did not differ significantly between BMD and control dogs except for L. copenhageni antibody titers which were higher in BMD. Significantly higher antibody titers to L. canicola (p = 0.003), L. copenhageni (p = 0.005), L. grippothyphosa (p = 0.029) and L. vanderhoedoni (p = 0.035) were seen in BMD compared to control dogs. CONCLUSION AND CLINICAL RELEVANCE: BMD had a higher prevalence of anti-Bbsl, anti-L. copenhageni and anti-Ap antibodies than control dogs. Significantly higher antibody titers against L. canicola (p = 0.003), L. copenhageni (p = 0.005), L. grippothyphosa (p = 0.029) and L. vanderhoedoni (p = 0.035) were seen in BMD compared with control dogs, but the reason for this and potential clinical implications are not known.


Assuntos
Anaplasma phagocytophilum/imunologia , Anticorpos Antibacterianos/sangue , Borrelia burgdorferi/imunologia , Doenças do Cão/epidemiologia , Leptospira interrogans/imunologia , Animais , Cruzamento , Doenças do Cão/genética , Doenças do Cão/microbiologia , Cães , Ehrlichiose/epidemiologia , Ehrlichiose/genética , Ehrlichiose/veterinária , Feminino , Alemanha/epidemiologia , Leptospirose/epidemiologia , Leptospirose/genética , Leptospirose/veterinária , Doença de Lyme/epidemiologia , Doença de Lyme/genética , Doença de Lyme/veterinária , Masculino , Prevalência
10.
Sci Rep ; 6: 22794, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26955886

RESUMO

The origin and population structure of Borrelia burgdorferi sensu stricto (s.s.), the agent of Lyme disease, remain obscure. This tick-transmitted bacterial species occurs in both North America and Europe. We sequenced 17 European isolates (representing the most frequently found sequence types in Europe) and compared these with 17 North American strains. We show that trans-Atlantic exchanges have occurred in the evolutionary history of this species and that a European origin of B. burgdorferi s.s. is marginally more likely than a USA origin. The data further suggest that some European human patients may have acquired their infection in North America. We found three distinct genetically differentiated groups: i) the outgroup species Borrelia bissettii, ii) two divergent strains from Europe, and iii) a group composed of strains from both the USA and Europe. Phylogenetic analysis indicated that different genotypes were likely to have been introduced several times into the same area. Our results demonstrate that irrespective of whether B. burgdorferi s.s. originated in Europe or the USA, later trans-Atlantic exchange(s) have occurred and have shaped the population structure of this genospecies. This study clearly shows the utility of next generation sequencing to obtain a better understanding of the phylogeography of this bacterial species.


Assuntos
Borrelia burgdorferi/classificação , Borrelia burgdorferi/genética , Variação Genética , Doença de Lyme/epidemiologia , Doença de Lyme/microbiologia , Europa (Continente)/epidemiologia , Evolução Molecular , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Epidemiologia Molecular , Filogenia , Análise de Sequência de DNA , Estados Unidos/epidemiologia
11.
J Microsc ; 262(2): 171-7, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26224521

RESUMO

The usable aperture sizes in (scanning) transmission electron microscopy ((S)TEM) have significantly increased in the past decade due to the introduction of aberration correction. In parallel with the consequent increase of convergence angle the depth of focus has decreased severely and optical sectioning in the STEM became feasible. Here we apply STEM defocus series to derive the local sample thickness of a TEM sample. To this end experimental as well as simulated defocus series of thin Si foils were acquired. The systematic blurring of high resolution high angle annular dark field images is quantified by evaluating the standard deviation of the image intensity for each image of a defocus series. The derived dependencies exhibit a pronounced maximum at the optimum defocus and drop to a background value for higher or lower values. The full width half maximum (FWHM) of the curve is equal to the sample thickness above a minimum thickness given by the size of the used aperture and the chromatic aberration of the microscope. The thicknesses obtained from experimental defocus series applying the proposed method are in good agreement with the values derived from other established methods. The key advantages of this method compared to others are its high spatial resolution and that it does not involve any time consuming simulations.

12.
Artigo em Alemão | MEDLINE | ID: mdl-26134062

RESUMO

OBJECTIVE: Because of an increase in the number of cases of bovine tuberculosis in southern Germany (Allgäu region, mainly in the administrative district Swabia) during recent years, blanket tuberculosis testing was resumed in this region. The aim of this study was to review the veterinarians' current knowledge regarding the technique of the intradermal tuberculin test. As a consequence, a guide with precise instructions for the execution and interpretation of intradermal tuberculin testing in cattle based on the current legislation should be created. MATERIAL AND METHODS: Using a questionnaire, farm-animal practitioners' knowledge and experiences of intradermal tuberculin testing were surveyed, collected and evaluated. Legislative texts on tuberculosis (particularly testing of tuberculosis) were evaluated in their current and previous versions, and compared with the experiences reported by the veterinarians. RESULTS: A total of 137 veterinarians participated and 130 returned questionnaires could be evaluated. Forty-four of the 130 participants were involved in tuberculosis testing when the survey was performed. Of these 44 questionnaires, 42 were incorporated in the final evaluation. The majority of the veterinarians perform the intradermal tuberculosis test as laid down in the Commission Regulation (EC) no. 1226/2002 of 8 July 2002 amending Annex B to Council Directive 64/432/EEC. However, many practitioners do not comply with the requirements of the Commission Regulation (EC) no. 1226/2002 when evaluating the results of the intradermal tuberculosis test. Veterinarians showing the least accordance with required standards only test single animals or work in areas other than Swabia. CONCLUSIONS: In areas severely affected by tuberculosis, the technique of intradermal tuberculosis testing is performed almost as demanded by the Commission Regulation (EC) no. 1226/2002. However, a more uniform and careful approach should be sought when monitoring the results. The guide designed in the context of this study can help to improve the performance of the intradermal tuberculosis test. The information from the literature review also shows that there is currently no standardized method of intradermal tuberculosis testing.


Assuntos
Testes Intradérmicos/estatística & dados numéricos , Teste Tuberculínico/estatística & dados numéricos , Tuberculose Bovina/diagnóstico , Médicos Veterinários/estatística & dados numéricos , Criação de Animais Domésticos , Animais , Bovinos , Alemanha , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Inquéritos e Questionários
13.
Vet Rec ; 176(12): 309, 2015 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-25568184

RESUMO

In dogs with idiopathic acute haemorrhagic diarrhoea syndrome (AHDS), a serious loss of intestinal mucosal barrier integrity occurs. However, the incidence of bacterial translocation in dogs with idiopathic AHDS is not known. Thus, the objectives of this prospective study were to identify the incidence of bacteraemia, to evaluate the frequency of septic events and the influence of bacteraemia on various clinical and laboratory parameters, duration of hospitalisation and survival of dogs with idiopathic AHDS. The study included 87 dogs with idiopathic AHDS. Twenty-one healthy dogs served as control group. To evaluate clinical significance of bacterial translocation, blood culture results were compared between patients and controls. Clinical and laboratory parameters were compared between patients with positive and negative blood cultures. There was no significant difference in either incidence of bacteraemia between patients with idiopathic AHDS (11 per cent) and controls (14 per cent) or in severity of clinical signs, laboratory parameters, duration of hospitalisation or mortality between blood culture-positive and culture-negative dogs with idiopathic AHDS. The results of this study suggest that the incidence of bacteraemia in dogs with idiopathic AHDS is low and not different from that of healthy control dogs. Bacteraemia does not influence the clinical course or survival and thus antibiotic treatment is not indicated to prevent sepsis.


Assuntos
Bacteriemia/veterinária , Diarreia/veterinária , Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia , Hemorragia Gastrointestinal/veterinária , Doença Aguda , Animais , Bacteriemia/epidemiologia , Estudos de Casos e Controles , Diarreia/microbiologia , Cães , Feminino , Hemorragia Gastrointestinal/microbiologia , Alemanha/epidemiologia , Masculino , Estudos Prospectivos , Síndrome
14.
Vet Rec ; 176(14): 357, 2015 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-25467146

RESUMO

The aim of this study was to investigate the prevalence of bacterial species isolated from bronchoalveolar lavage fluid (BALF) samples taken from dogs with respiratory signs and to determine their antibiotic susceptibility. Clinical cases were included in the study if they showed signs of respiratory disease and data relating to bacterial culture and susceptibility of BALF samples were available. The medical records of 493 privately owned dogs that were presented between January 1989 and December 2011 were evaluated retrospectively. In 35 per cent of samples, no bacteria were cultured. Bacteria isolated from culture-positive samples included Streptococcus species (31 per cent of positive cultures), Enterobacteriaceae (30 per cent, including Escherichia coli (15 per cent)), Staphylococcus species (19 per cent), Pasteurella species (16 per cent) and Pseudomonas species (14 per cent). Bordetella bronchiseptica as a primary respiratory pathogen was isolated in 8 per cent of cases. Enrofloxacin showed the best susceptibility pattern; 86 per cent of all isolates and 87 per cent of Gram-negative bacteria were susceptible to this antibiotic. Amoxicillin/clavulanic acid yielded the best susceptibility pattern in Gram-positive bacteria (92 per cent). Therefore, these antibiotics can be recommended for empirical or first-line treatment in dogs with bacterial lower respiratory tract infections.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/veterinária , Doenças do Cão/tratamento farmacológico , Doenças do Cão/microbiologia , Farmacorresistência Bacteriana , Infecções Respiratórias/veterinária , Animais , Antibacterianos/uso terapêutico , Bactérias/isolamento & purificação , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Líquido da Lavagem Broncoalveolar/microbiologia , Cães , Feminino , Masculino , Testes de Sensibilidade Microbiana/veterinária , Registros , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/microbiologia , Estudos Retrospectivos , Resultado do Tratamento , Medicina Veterinária
15.
J Vet Intern Med ; 28(1): 52-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24205886

RESUMO

BACKGROUND: Etiology of hemorrhagic gastroenteritis (HGE) syndrome in dogs is unknown and histopathologic and microbial investigations have only been performed post mortem. OBJECTIVE: To identify characteristic intra vitam endoscopic and histologic mucosal lesions, as well as bacterial species, within the mucosa of dogs with HGE. ANIMALS: Ten dogs diagnosed with HGE were included. Eleven dogs with gastroduodenoscopy and different intestinal diseases were used as controls for microbial changes. Dogs pretreated with antibiotics or diagnosed with any disease known to cause bloody diarrhea were excluded from the study. METHODS: In this prospective study, gastrointestinal biopsies were collected from 10 dogs with HGE. Endoscopic and histologic changes were assessed according to WSAVA guidelines. Biopsies from the stomach, duodenum, ileum, and colon were investigated by histology and by immunohistochemistry for the presence of Clostridium spp. and parvovirus. The first duodenal biopsy taken with a sterile forceps was submitted for bacterial culture. RESULTS: Acute mucosal lesions were only found in the intestines, not in the stomach. Clostridium spp., identified as Clostridium perfringens in 6/9 cases, were detected on the small intestinal mucosa in all dogs with HGE, either by culture or immunohistopathology. In the control group, C. perfringens could only be cultured in one of 11 dogs. CONCLUSIONS AND CLINICAL IMPORTANCE: The results of this study demonstrate an apparent association between C. perfringens and the occurrence of acute hemorrhagic diarrhea. The term "HGE," which implies the involvement of the stomach, should be renamed as "acute hemorrhagic diarrhea syndrome."


Assuntos
Infecções por Clostridium/veterinária , Clostridium perfringens/crescimento & desenvolvimento , Doenças do Cão/microbiologia , Doenças do Cão/patologia , Hemorragia Gastrointestinal/veterinária , Animais , Biópsia/veterinária , Infecções por Clostridium/microbiologia , Infecções por Clostridium/patologia , Contagem de Colônia Microbiana , Cães , Hemorragia Gastrointestinal/microbiologia , Hemorragia Gastrointestinal/patologia , Imuno-Histoquímica/veterinária , Mucosa Intestinal/microbiologia , Mucosa Intestinal/fisiologia , Estudos Prospectivos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
16.
Br J Cancer ; 110(2): 320-9, 2014 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-24327018

RESUMO

BACKGROUND: Fibroblast growth factor receptor (FGFR) signalling has been implicated in pancreas carcinogenesis. We investigated the effect of FGFR inhibition in pancreatic cancer in complementary cancer models derived from cell lines and patient-derived primary tumour explants. METHODS: The effects of FGFR signalling inhibition in pancreatic cancer were evaluated using anti-FRS2 shRNA and dovitinib. Pancreatic cancers with varying sensitivity to dovitinib were evaluated to determine potential predictive biomarkers of efficacy. Primary pancreatic explants with opposite extreme of biomarker expression were selected from 13 tumours for in vivo dovitinib treatment. RESULTS: Treatment with anti-FRS2 shRNA induced significant in vitro cell kill in pancreatic cancer cells. Dovitinib treatment achieved similar effects and was mediated by Akt/Mcl-1 signalling in sensitive cells. Dovitinib efficacy correlated with FRS2 phosphorylation status, FGFR2 mRNA level and FGFR2 IIIb expression but not phosphorylation status of VEGFR2 and PDGFRß. Using FGFR2 mRNA level, a proof-of-concept study using primary pancreatic cancer explants correctly identified the tumours' sensitivity to dovitinib. CONCLUSION: Inhibiting FGFR signalling using shRNA and dovitinib achieved significant anti-cancer cancer effects in pancreatic cancer. The effect was more pronounced in FGFR2 IIIb overexpressing pancreatic cancer that may be dependent on aberrant stimulation by stromal-derived FGF ligands.


Assuntos
Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/genética , Benzimidazóis/farmacologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinogênese/genética , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Neoplasias Pancreáticas/genética , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinolonas/farmacologia , RNA Interferente Pequeno/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Transdução de Sinais/efeitos dos fármacos
17.
J Food Prot ; 76(6): 1056-61, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23726205

RESUMO

Toxoplasma gondii is one of the most common zoonotic parasites in the world. The parasite causes no or mild symptoms in immunocompetent humans. However, a high potential hazard exists for seronegative pregnant women and immunocompromised patients. The consumption of meat containing tissue cysts or oocyst-contaminated vegetables and fruits or the handling of cat feces poses a high risk of infection with T. gondii. It is known that raw minced meat, raw fresh sausages, and locally produced raw meat products are possible causes of T. gondii infection. The infectivity of T. gondii tissue cysts in meat products depends, among other factors, on the pH and the salt concentration. Therefore, the impact of these two factors on the tissue cysts was examined. For this purpose, dissected musculature and brain from experimentally infected mice (donor mice) were placed in a cell culture medium (RPMI 1640). The medium was adjusted to different pH values (pH 5, 6, and 7) with lactic acid and to different salt concentrations (2.0, 2.5, and 3.0%) with sodium chloride (NaCl) or nitrite-enriched curing salt (NCS) for the various tests. After storage at 4°C for different time periods, the materials were fed to bioassay mice. Later, the brains were examined for presence of T. gondii to assess the infectivity. The data show that T. gondii tissue cysts have a high pH tolerance. Cysts were infectious in the muscle for up to 26 days (pH 5). In contrast to their tolerance to pH, cysts were very sensitive to salt. Muscle cysts survived at an NaCl concentration of up to 2.0% only, and for no longer than 8 days. At NaCl concentrations of 2.5 and 3.0%, the cysts lost their infectivity after 1 day. When NCS instead of NaCl was used under the same conditions, T. gondii muscle cysts retained infectivity for only 4 days at 2.0%. Consequently, NCS (NaCl plus 0.5% nitrite) has a stronger effect on T. gondii cysts than does common table salt. Sausages produced with low NaCl concentration and short contact times pose a potential risk for susceptible individuals.


Assuntos
Conservação de Alimentos/métodos , Conservantes de Alimentos/farmacologia , Produtos da Carne/parasitologia , Oocistos/efeitos dos fármacos , Toxoplasma/efeitos dos fármacos , Animais , Gatos , Qualidade de Produtos para o Consumidor , Fezes/parasitologia , Feminino , Manipulação de Alimentos/métodos , Parasitologia de Alimentos , Humanos , Concentração de Íons de Hidrogênio , Lactatos/farmacologia , Camundongos , Gravidez , Sais/farmacologia , Cloreto de Sódio/farmacologia , Suínos , Fatores de Tempo , Toxoplasma/fisiologia
18.
Vet Parasitol ; 196(3-4): 272-7, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-23608035

RESUMO

Toxoplasma (T.) gondii is a protozoan parasite with a broad range of intermediate hosts. Humans are often infected by ingestion of tissue cysts in raw or undercooked meat or meat products. Turkeys as food-producing animals can also serve as intermediate hosts. The aim of the present study was to investigate occurrence and predilection sites of T. gondii infection in turkeys after oral infection with oocysts. Experimental infections with different doses of T. gondii oocysts were performed in 36 turkeys to mimic natural infection. Systemic distribution of parasitic stages was investigated by screening 14 different tissues including the edible tissues heart, liver, thigh, breast and drumstick muscle. Parasite detection was based on a conventional nested polymerase chain reaction (PCR). Animals were sacrificed 6-12 weeks after infection. Results demonstrated parasite spreading over the whole organism after oral infection by oocysts. Most frequently affected tissues were brain (47.2% of all brains were positive for T. gondii) and thigh muscle (25.0% positive samples). Other muscles were regularly T. gondii-positive, all other sampled tissues were positive at least once. Thus, edible tissues are one of the predilection sites of T. gondii in turkeys which renders raw or undercooked turkey meat a potential risk for parasite transmission to humans. Data were compared to results from previous parenteral turkey infections with tachyzoites. With the exception of brain, liver and breast muscle affection, no significant differences were observed between both infection routes. Both infection models could be used for research purposes with certain advantages and disadvantages.


Assuntos
Oocistos/fisiologia , Doenças das Aves Domésticas/parasitologia , Toxoplasma/fisiologia , Toxoplasmose Animal/parasitologia , Perus , Animais , Moela das Aves/parasitologia , Fígado/parasitologia , Pulmão/parasitologia , Masculino , Músculo Esquelético/parasitologia , Pâncreas/parasitologia , Baço/parasitologia , Testículo/parasitologia , Toxoplasmose Animal/patologia
19.
Parasitol Res ; 112(5): 1841-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23408341

RESUMO

Turkeys are known to be natural hosts for the zoonotic protozoan parasite Toxoplasma gondii. The objective of the present study was to gain further knowledge of possible predilection sites of T. gondii infection in this species after parenteral application of tachyzoites. A total of 38 turkeys were infected with different doses of T. gondii tachyzoites. Birds were killed either 6 to 8 or 10 to 12 weeks after the experimental infection. Fourteen different tissues per bird were investigated by a nested polymerase chain reaction (PCR) for the presence of the parasites' DNA. T. gondii DNA was found in any type of tissue analysed; in 86.1 % of all infected birds, at least one sample was tested positive. Over all intravenously infected birds, 15.4 % of all analysed samples contained T. gondii DNA. Most frequently affected tissues were liver (43.3 % positive samples), breast muscle (26.7 % positive samples) and heart (20.0 % positive samples), while the brain was less frequently positive (6.7 %). The number of positive tissues varied from zero to seven tissues per animal with at least one T. gondii-positive edible tissue sample in 80 % of all intravenously infected birds. Still, the results did not indicate defined target tissues or a cyst distribution pattern. Nonetheless, edible organs were most frequently parasitised. The number of positive findings did not differ between the early and the late examination time points. Therefore, a persistence of the tissue stages until the end of the study (12 weeks after infection) is concluded.


Assuntos
Mama/parasitologia , Fígado/parasitologia , Toxoplasma/patogenicidade , Toxoplasmose Animal/parasitologia , Tropismo , Perus/parasitologia , Administração Intranasal , Administração Intravenosa , Animais , Anticorpos Antiprotozoários/sangue , DNA de Protozoário/análise , DNA de Protozoário/isolamento & purificação , Feminino , Coração/parasitologia , Masculino , Reação em Cadeia da Polimerase , Distribuição Tecidual , Toxoplasma/genética , Toxoplasma/crescimento & desenvolvimento , Toxoplasma/imunologia , Toxoplasmose Animal/imunologia
20.
Lett Appl Microbiol ; 54(1): 26-31, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22023239

RESUMO

AIMS: Commercially available selective media for methicillin-resistant Staphylococcus aureus (MRSA) were tested for the detection and isolation of methicillin-resistant Staphylococcus pseudintermedius (MRSP). METHODS AND RESULTS: Five different screening agars [mannitol salt agar with oxacillin and BD BBL™ Chromagar™ MRSA (BD Diagnostics); chromID™ MRSA agar (bioMérieux); Oxacillin resistance screening agar base (ORSAB); and Brilliance MRSA agar (Oxoid)] were analysed for the detection of MRSP. Bacteria that may be isolated together with MRSP and may grow on the screening agars were included in the study to determine possible interference with the growth of MRSP. MRSP grew well on all selective media except on BD BBL™ Chromagar™ MRSA (BD Diagnostics) and chromID™ MRSA agar (bioMérieux), on which a low to moderate growth rate was noted. CONCLUSIONS: ORSAB (Oxoid) and Brilliance MRSA agar (Oxoid) are most suitable for the detection and isolation of MRSP from clinical material. SIGNIFICANCE AND IMPACT OF THE STUDY: The importance of MRSP in veterinary medicine is increasing. Diagnostic systems are needed to detect MRSP carrier as soon as possible. This study provides information about selected MRSA screening agars for the detection of MRSP to the clinical microbiologists.


Assuntos
Meios de Cultura/química , Doenças do Cão/diagnóstico , Resistência a Meticilina , Infecções Estafilocócicas/veterinária , Staphylococcus/isolamento & purificação , Ágar/química , Animais , Portador Sadio , Doenças do Cão/microbiologia , Cães , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Oxacilina/farmacologia , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/microbiologia , Staphylococcus/efeitos dos fármacos , Staphylococcus/crescimento & desenvolvimento
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