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1.
Epidemiol Infect ; 144(6): 1257-66, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26548371

RESUMEN

Injecting drug use is often associated with deep-seated infection. In Lothian in Scotland there has been a recent increase in the use of injected new psychoactive substances (NPS). Patients who have injected NPS have presented with Staphylococcus aureus bacteraemia (SAB) with life-threatening complications. We describe a unique case-series of 14 episodes of SAB in ten patients. Users of injected NPS had a significantly higher incidence of endocarditis and cavitating pulmonary lesions (P < 0·05) compared to those who inject only opiates. Cases of SAB in people who inject NPS have contributed to a significant rise in the overall incidence of SAB in people who inject drugs (P < 0·05) which has in turn impacted on the ability of Lothian to meet national targets for reducing the incidence of SAB.


Asunto(s)
Bacteriemia/epidemiología , Bacteriemia/etiología , Drogas de Diseño/efectos adversos , Psicotrópicos/efectos adversos , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/etiología , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adolescente , Adulto , Bacteriemia/microbiología , Femenino , Humanos , Drogas Ilícitas/efectos adversos , Inyecciones/efectos adversos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Escocia/epidemiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/fisiología , Adulto Joven
2.
Br J Biomed Sci ; 69(3): 112-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23057158

RESUMEN

The laboratory diagnosis of Clostridium difficile infection (CDI) needs to be accurate and timely to ensure optimal patient management, infection control and reliable surveillance. Three methods are evaluated using 810 consecutive stool samples against toxigenic culture: CDT TOX A/B Premier enzyme immunoassay (EIA) kit (Meridian Bioscience, Europe), Premier EIA for C. difficile glutamate dehydrogenase (GDH) (Meridian Bioscience, Europe) and the Illumigene kit (Meridian Bioscience, Europe), both individually and within combined testing algorithms. The study revealed that the CDT TOX A/B Premier EIA gave rise to false-positive and false-negative results and demonstrated poor sensitivity (56.47%), compared to Premier EIA for C. difficile GDH (97.65%), suggesting this GDH EIA can be a useful negative screening method. Results for the Illumigene assay alone showed sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) of 91.57%, 98.07%, 99.03% and 84.44%, respectively. A two-stage algorithm using Premier EIA for C. difficile GDH/Illumigene assay yielded superior results compared with other testing algorithms (91.57%, 98.07%, 99.03% and 84.44%, respectively), mirroring the Illumigene performance. However, Illumigene is approximately half the cost of current polymerase chain reaction (PCR) methods, has a rapid turnaround time and requires no specialised skill base, making it an attractive alternative to assays such as the Xpert C. difficile assay (Cepheid, Sunnyvale, CA). A three-stage algorithm offered no improvement and would hamper workflow.


Asunto(s)
Técnicas Bacteriológicas/métodos , Clostridioides difficile/aislamiento & purificación , Infecciones por Clostridium/diagnóstico , Infecciones por Clostridium/microbiología , Glutamato Deshidrogenasa/análisis , Algoritmos , Proteínas Bacterianas/análisis , Proteínas Bacterianas/genética , Proteínas Bacterianas/toxicidad , Toxinas Bacterianas/análisis , Toxinas Bacterianas/genética , Toxinas Bacterianas/toxicidad , Técnicas de Cultivo de Célula , Clostridioides difficile/genética , Enterotoxinas/análisis , Enterotoxinas/genética , Enterotoxinas/toxicidad , Heces/microbiología , Humanos , Técnicas para Inmunoenzimas/métodos , Pruebas de Neutralización , Reacción en Cadena de la Polimerasa/métodos , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad
3.
Infect Immun ; 79(5): 2089-97, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21321071

RESUMEN

Although the causative agent of Johne's disease, Mycobacterium avium subsp. paratuberculosis, is well known, the etiology of disease and the immune responses generated in response to infection are still poorly understood. Knowledge of definitive markers of protective immunity, infection, and the establishment of chronic granulomatous Johne's disease is necessary to advance vaccine and diagnostic development. We sought to profile the immune responses occurring within jejunal lymph nodes of experimentally challenged red deer (Cervus elaphus). Quantitative PCR was utilized to measure a range of cytokines, signaling molecules, and transcription factors involved in Th1, Th2, Treg, and Th17 immune responses. Significant differences in gene expression were observed between control, minimally diseased, and severely diseased animals, with severely diseased animals showing elevated proinflammatory transcripts and reduced anti-inflammatory transcripts. We identified a proinflammatory cytokine milieu of gamma interferon, interleukin-1α (IL-1α), and IL-17, which may contribute to the immunopathology observed during clinical Johne's disease and suggest that Th2 and Treg immune responses may play an important role in controlling the development of immunopathology in infected animals.


Asunto(s)
Citocinas/biosíntesis , Ciervos/inmunología , Perfilación de la Expresión Génica , Paratuberculosis/genética , Paratuberculosis/inmunología , Animales , Citocinas/inmunología , Ciervos/microbiología , Femenino , Expresión Génica , Mycobacterium avium subsp. paratuberculosis/inmunología , Paratuberculosis/patología
4.
J Antimicrob Chemother ; 66(2): 408-15, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21118914

RESUMEN

OBJECTIVES: We describe failure rates of 198 patients with bone and joint infection (BJI), including prosthetic joint infection and diabetic foot osteomyelitis, managed through the Glasgow centre for outpatient parenteral antibiotic therapy (OPAT) over a period of 4 years. Outcomes following initial intravenous antimicrobial therapy and a median follow-up time of 60 weeks are described. PATIENTS AND METHODS: A prospectively maintained registry of all patients attending OPAT was examined for cases of BJI. Once identified, patient case records were reviewed and data extracted. Diagnosis, demographics, microbiology and treatment were recorded, and case records were examined for evidence of failing initial prescribed OPAT therapy and up to 24 months of follow-up. RESULTS: One hundred and ninety-eight cases of BJI were identified. The overall success rate following initial OPAT was 86.4%, with a range from 71.8% success rate for diabetic foot or stump infection (DFI) to 100% for metalwork-related infection. The failure rate over the follow-up period was 29.8%. Factors associated with poor initial outcome included older age, methicillin-resistant Staphylococcus aureus infection and DFI, factors that continued to explain failure up to 24 months in multivariate survival analysis. CONCLUSIONS: For the majority of conditions, BJI can be successfully managed through OPAT. Identification of those likely to respond less well, including older patients, those with DFI and those with infections by resistant organisms, may encourage enhanced vigilance and consideration of newer or more aggressive treatments in these subgroups of patients.


Asunto(s)
Antibacterianos/uso terapéutico , Enfermedades Óseas Infecciosas/tratamiento farmacológico , Artropatías/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/administración & dosificación , Artritis Infecciosa/microbiología , Enfermedades Óseas Infecciosas/microbiología , Diabetes Mellitus/etiología , Femenino , Enfermedades del Pie/microbiología , Humanos , Artropatías/microbiología , Masculino , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Persona de Mediana Edad , Pacientes Ambulatorios , Factores de Riesgo , Insuficiencia del Tratamiento , Reino Unido
5.
Vet Pathol ; 48(2): 525-9, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20881317

RESUMEN

This article describes the histopathology of grossly normal mesenteric lymph nodes (MLNs) of New Zealand farmed red deer (Cervus elaphus). Eighty MLNs were sourced from 10 deer from 5 North Island herds and 5 South Island herds classified as low risk and high risk of Mycobacterium avium subspecies paratuberculosis (MAP) infection, respectively. Fixed sections were stained with hematoxylin and eosin; Ziehl-Neelsen; and, selectively, periodic acid-Schiff, Perl's, and Sudan black. Positive Ziehl-Neelsen stain, follicular hyperplasia, capsular eosinophil infiltration, focal granulomas, foci of macrophages containing lipopigment, parasitic granulomas, and calcified foci are described and severity graded where appropriate. Animal age, sex, and herd of origin are variably associated with the presence of one or more features. Trabecular fibrosis and dilated edema-filled sinusoids are described. These observations allow differentiation between likely nonpathologic histologic features in deer MLNs and features possibly attributable to infection with a pathogen such as MAP.


Asunto(s)
Ciervos , Ganglios Linfáticos/patología , Linfadenitis Mesentérica/patología , Linfadenitis Mesentérica/veterinaria , Mycobacterium avium subsp. paratuberculosis , Paratuberculosis/complicaciones , Factores de Edad , Animales , Femenino , Técnicas Histológicas/veterinaria , Lípidos/análisis , Ganglios Linfáticos/anatomía & histología , Masculino , Linfadenitis Mesentérica/etiología , Nueva Zelanda , Factores de Riesgo , Factores Sexuales
6.
Diabetologia ; 52(5): 891-900, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19252894

RESUMEN

AIMS/HYPOTHESIS: TBC1 domain family, member 4 (TBC1D4; also known as AS160) is a cellular signalling intermediate to glucose transport regulated by insulin-dependent and -independent mechanisms. Skeletal muscle insulin sensitivity is increased after acute exercise by an unknown mechanism that does not involve modulation at proximal insulin signalling intermediates. We hypothesised that signalling through TBC1D4 is involved in this effect of exercise as it is a common signalling element for insulin and exercise. METHODS: Insulin-regulated glucose metabolism was evaluated in 12 healthy moderately trained young men 4 h after one-legged exercise at basal and during a euglycaemic-hyperinsulinaemic clamp. Vastus lateralis biopsies were taken before and immediately after the clamp. RESULTS: Insulin stimulation increased glucose uptake in both legs, with greater effects (approximately 80%, p < 0.01) in the previously exercised leg. TBC1D4 phosphorylation, assessed using the phospho-AKT (protein kinase B)substrate antibody and phospho- and site-specific antibodies targeting six phosphorylation sites on TBC1D4, increased at similar degrees to insulin stimulation in the previously exercised and rested legs (p < 0.01). However, TBC1D4 phosphorylation on Ser-318, Ser-341, Ser-588 and Ser-751 was higher in the previously exercised leg, both in the absence and in the presence of insulin (p < 0.01; Ser-588, p = 0.09; observed power = 0.39). 14-3-3 binding capacity for TBC1D4 increased equally (p < 0.01) in both legs during insulin stimulation. CONCLUSION/INTERPRETATION: We provide evidence for site-specific phosphorylation of TBC1D4 in human skeletal muscle in response to physiological hyperinsulinaemia. The data support the idea that TBC1D4 is a nexus for insulin- and exercise-responsive signals that may mediate increased insulin action after exercise.


Asunto(s)
Ejercicio Físico/fisiología , Proteínas Activadoras de GTPasa/fisiología , Insulina/fisiología , Músculo Esquelético/fisiología , Tejido Adiposo/citología , Tejido Adiposo/fisiología , Adulto , Biopsia , Glucemia/metabolismo , Cartilla de ADN , Dieta , Proteínas Activadoras de GTPasa/genética , Proteínas Activadoras de GTPasa/metabolismo , Humanos , Hiperinsulinismo/etiología , Articulación de la Rodilla/fisiología , Pierna/fisiología , Masculino , Consumo de Oxígeno , Fosforilación , Descanso , Transducción de Señal , Posición Supina , Carga de Trabajo , Adulto Joven
7.
Br J Cancer ; 101(1): 80-90, 2009 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-19491900

RESUMEN

BACKGROUND: Ewing sarcoma is a paradigm of solid tumour -bearing chromosomal translocations resulting in fusion proteins that act as deregulated transcription factors. Ewing sarcoma translocations fuse the EWS gene with an ETS transcription factor, mainly FLI1. Most of the EWS-FLI1 target genes still remain unknown and many have been identified in heterologous model systems. METHODS: We have developed a stable RNA interference model knocking down EWS-FLI1 in the Ewing sarcoma cell line TC71. Gene expression analyses were performed to study the effect of RNA interference on the genetic signature of EWS-FLI1 and to identify genes that could contribute to tumourigenesis. RESULTS: EWS-FLI1 inhibition induced apoptosis, reduced cell migratory and tumourigenic capacities, and caused reduction in tumour growth. IGF-1 was downregulated and the IGF-1/IGF-1R signalling pathway was impaired. PBK/TOPK (T-LAK cell-originated protein kinase) expression was decreased because of EWS-FLI1 inhibition. We showed that TOPK is a new target gene of EWS-FLI1. TOPK inhibition prompted a decrease in the proliferation rate and a dramatic change in the cell's ability to grow in coalescence. CONCLUSION: This is the first report of TOPK activity in Ewing sarcoma and suggests a significant role of this MAPKK-like protein kinase in the Ewing sarcoma biology.


Asunto(s)
Factor I del Crecimiento Similar a la Insulina/metabolismo , Proteínas de Fusión Oncogénica/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/biosíntesis , Receptor IGF Tipo 1/metabolismo , Sarcoma de Ewing/metabolismo , Factores de Transcripción/antagonistas & inhibidores , Animales , Apoptosis/fisiología , Línea Celular Tumoral , Movimiento Celular/fisiología , Regulación hacia Abajo , Femenino , Humanos , Factor I del Crecimiento Similar a la Insulina/antagonistas & inhibidores , Factor I del Crecimiento Similar a la Insulina/biosíntesis , Factor I del Crecimiento Similar a la Insulina/genética , Ratones , Ratones Endogámicos NOD , Ratones SCID , Quinasas de Proteína Quinasa Activadas por Mitógenos , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteína Proto-Oncogénica c-fli-1 , Interferencia de ARN , Proteína EWS de Unión a ARN , Receptor IGF Tipo 1/antagonistas & inhibidores , Receptor IGF Tipo 1/biosíntesis , Receptor IGF Tipo 1/genética , Sarcoma de Ewing/enzimología , Sarcoma de Ewing/genética , Sarcoma de Ewing/patología , Transducción de Señal , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
8.
Trends Biochem Sci ; 19(11): 444-8, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7855884

RESUMEN

Inhibitors of eukaryotic protein kinases and phosphatases are a chemically diverse array of natural and synthetic compounds, including medicines, potions and poisons. These substances are valuable pharmacological probes and affinity ligands for the kinases and phosphatases of signalling pathways, enhancing our knowledge of the cellular effects of the pathway in question. More broadly, this basic research is also leading to the development of drugs to control specific cellular responses, and enzyme-based assays to detect toxins in food and water.


Asunto(s)
Monoéster Fosfórico Hidrolasas/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas , Animales , Células Eucariotas , Estructura Molecular
9.
J R Coll Physicians Edinb ; 48(4): 304-310, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30488883

RESUMEN

BACKGROUND: Staphylococcus aureus infective endocarditis (IE) associated with injection of new psychoactive substances (NPS) in Edinburgh from 2014 to 2016 was observed. We compared these infections with a series of S. aureus IE cases in a non-injecting population within Edinburgh. METHODS: NPS-associated S. aureus IE diagnosed between 1 January 2014 and 31 May 2016 in persons who inject drugs (PWID) were compared with a series of S. aureus IE cases from non-PWID. RESULTS: There was a fourfold increase in the annual incidence of S. aureus IE, mainly due to NPS use in PWID. A larger vegetation diameter was seen on echocardiogram in PWID vs non-PWID (median 1.7 cm vs 0.65 cm; p = 0.009) with more embolic complications in PWID (15 PWID vs 1 non-PWID; p = 2.1 x 10-7) but no difference in 90-day mortality (2 PWID vs 4 non-PWID; p = 0.39). CONCLUSIONS: NPS-associated S. aureus IE correlated with complications, such as deep organ embolic abscesses, that were different from non-PWID S. aureus IE. The alarming increase in incidence resolved with targeted public health and legislative measures.


Asunto(s)
Endocarditis Bacteriana/epidemiología , Infecciones Estafilocócicas/epidemiología , Abuso de Sustancias por Vía Intravenosa/complicaciones , Adulto , Anciano , Ecocardiografía , Embolia/microbiología , Endocarditis Bacteriana/diagnóstico por imagen , Endocarditis Bacteriana/microbiología , Endocarditis Bacteriana/mortalidad , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Psicotrópicos , Escocia/epidemiología , Infecciones Estafilocócicas/etiología , Staphylococcus aureus
10.
Transbound Emerg Dis ; 65 Suppl 1: 125-148, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-28941207

RESUMEN

In the last decades, many regional and country-wide control programmes for Johne's disease (JD) were developed due to associated economic losses, or because of a possible association with Crohn's disease. These control programmes were often not successful, partly because management protocols were not followed, including the introduction of infected replacement cattle, because tests to identify infected animals were unreliable, and uptake by farmers was not high enough because of a perceived low return on investment. In the absence of a cure or effective commercial vaccines, control of JD is currently primarily based on herd management strategies to avoid infection of cattle and restrict within-farm and farm-to-farm transmission. Although JD control programmes have been implemented in most developed countries, lessons learned from JD prevention and control programmes are underreported. Also, JD control programmes are typically evaluated in a limited number of herds and the duration of the study is less than 5 year, making it difficult to adequately assess the efficacy of control programmes. In this manuscript, we identify the most important gaps in knowledge hampering JD prevention and control programmes, including vaccination and diagnostics. Secondly, we discuss directions that research should take to address those knowledge gaps.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Mycobacterium avium subsp. paratuberculosis/patogenicidad , Paratuberculosis/prevención & control , Animales , Bovinos , Enfermedades de los Bovinos/transmisión , Control de Enfermedades Transmisibles/métodos , Transmisión de Enfermedad Infecciosa/prevención & control , Transmisión de Enfermedad Infecciosa/veterinaria , Paratuberculosis/transmisión , Vacunación/veterinaria
11.
Curr Biol ; 6(9): 1104-13, 1996 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-8805370

RESUMEN

BACKGROUND: Nitrate reductase (NR) in leaves is rapidly inactivated in the dark by a two-step mechanism in which phosphorylation of NR on the serine at position 543 (Ser543) promotes binding to nitrate reductase inhibitor protein (NIP). The eukaryotic 14-3-3 proteins bind to many mammalian signalling components (Raf-1, Bcr, phosphoinositide 3-kinase, protein kinase C, polyomavirus middle-T antigen and Cdc25), and are implicated in the timing of mitosis, DNA-damage checkpoint control, exocytosis, and activation of the plant plasma-membrane H+-ATPase by fusicoccin. Their dimeric, saddle-shaped structures support the proposal that 14-3-3 proteins are 'adaptors' linking different signalling proteins, but their precise functions are still a mystery. RESULTS: We purified NIP to homogeneity and established by means of amino-acid sequencing that it is a mixture of several 14-3-3 isoforms. Mammalian and yeast 14-3-3 proteins were just as effective as NIP at inhibiting phosphorylated NR. The sequence around Ser543, the phosphorylation site in NR, is strikingly similar to the sequences around the phosphoserine residues (Ser259 and Ser621) of mammalian Raf-1 that interact with 14-3-3 proteins. We found that NIP activity was blocked by a synthetic phosphopeptide corresponding to residues 251-266 of Raf. Fusicoccin also blocked NIP activity, and plant plasma-membrane H+-ATPases were activated by either fusicoccin, the phosphoserine259-Raf-1 peptide, or protein phosphatase 2A. CONCLUSIONS: Our findings establish that the mechanism of inactivation of NR involves the phosphorylation of Ser 543 followed by interaction with one or more plant 14-3-3 proteins. These results support the idea of a common mechanism for binding of 14-3-3 to its targets in all eukaryotes, and suggest that the phosphoserine259-Raf-1 peptide and fusicoccin may be of general use for disrupting the interaction of 14-3-3 with its target proteins. We propose that the plant plasma-membrane H+-ATPase is regulated in an analogous manner to NR-NIP, and speculate that 14-3-3 proteins provide a link between 'sensing' the activity state of NR and signalling to other cellular processes in plants.


Asunto(s)
Glicósidos/metabolismo , Nitrato Reductasas/antagonistas & inhibidores , Nitrato Reductasas/metabolismo , Proteínas/metabolismo , Spinacia oleracea/enzimología , Tirosina 3-Monooxigenasa , Proteínas 14-3-3 , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Brassica/enzimología , Membrana Celular/enzimología , Cartilla de ADN , Activación Enzimática , Datos de Secuencia Molecular , Nitrato-Reductasa , Fosfoproteínas Fosfatasas/metabolismo , Fosforilación , Hojas de la Planta/enzimología , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Unión Proteica , Proteína Fosfatasa 2 , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas/química , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-raf , ATPasas de Translocación de Protón/metabolismo
12.
Amino Acids ; 33(2): 231-40, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17396215

RESUMEN

The polyamines spermidine and spermine have been hypothesized to possess different functions in the protection of DNA from reactive oxygen species. The growth and survival of mouse fibroblasts unable to synthesize spermine were compared to their normal counterparts in their native and polyamine-depleted states in response to oxidative stress. The results of these studies suggest that when present at normal or supraphysiological concentrations, either spermidine or spermine can protect cells from reactive oxygen species. However, when polyamine pools are pharmacologically manipulated to produce cells with low levels of predominately spermine or spermidine, spermine appears to be more effective. Importantly, when cells are depleted of both glutathione and endogenous polyamines, they exhibit increased sensitivity to hydrogen peroxide as compared to glutathione depletion alone, suggesting that polyamines not only play a role in protecting cells from oxidative stress but this role is distinct from that played by glutathione.


Asunto(s)
Peróxido de Hidrógeno/farmacología , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Espermidina/fisiología , Espermina/fisiología , Animales , Apoptosis , Células Cultivadas , Daño del ADN , Eflornitina/farmacología , Glutatión/farmacología , Guanidinas/farmacología , Etiquetado Corte-Fin in Situ , Ratones
13.
Curr Opin Plant Biol ; 1(3): 224-9, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10066593

RESUMEN

Recent discoveries have revealed that cytosolic enzymes of sugar, amino acid, and isoprenoid synthesis, sucrose breakdown and the plasma membrane H+-ATPase are regulated by reversible protein (serine/threonine) phosphorylation. In some cases, phosphorylation creates a phosphopeptide motif that is recognized by and binds to 14-3-3 proteins, and 14-3-3 binding changes the activity of the enzyme or ion pump. Intriguing new clues hint at how these cytosolic regulatory networks might link to signalling pathways triggered by hormones, nutrients, stresses, circadian rhythms, and other factors that regulate the growth and development of the whole plant.


Asunto(s)
Citosol/enzimología , Enzimas/metabolismo , Proteínas de Plantas/metabolismo , Tirosina 3-Monooxigenasa , Proteínas 14-3-3 , Activación Enzimática , Enzimas/genética , Fosforilación , Unión Proteica , Proteínas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transducción de Señal
14.
Tuberculosis (Edinb) ; 86(6): 404-18, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16337832

RESUMEN

Mycobacterium bovis infection produces tubercular lymphadenitis in the head lymphatics of cattle and deer, in addition to pulmonary disease. A low-dose intra-tonsilar infection model that establishes tuberculosis (Tb) lymphadenitis in cattle and deer is characterised in this study. Intra-tonsilar infection of red deer (500 cfus of M. bovis) was monitored longitudinally at 6-week intervals over a period of 23 weeks. Lesion characteristics, bacteriological and immunological parameters were assessed, and compared against those observed in cattle at 20 weeks post-infection, where the latter were infected with 500 or 5000 cfus of M. bovis. Intra-tonsilar inoculation of M. bovis established infection in >90% of deer and cattle, with lesion frequencies at the draining sentinel lymphatic site (left medial retropharyngeal node) of 68-86% and tissue bacterial burdens >3.5 logs/g of tissue, the tonsil being a major site of M. bovis persistence in deer only. Mineralisation occurred at lesion sites in both species in the later stages (18-23 weeks) of infection, with extensive coarse mineralisation observed mainly in cattle. The severity of infection or disease in cattle that received the higher or lower dose of M. bovis did not differ markedly. Pathogen-induced cellular immune response (lymphocyte transformation) and humoral responses (IgG and IgG(1) anti-mycobacterial antibodies) were recorded in both species, and the magnitude of these was noticeably amplified by skin tuberculin testing. IgG(1) antibodies were detectable within 6 weeks post-inoculation in deer and could be associated with early detection of lymphadenitis. Deer and cattle show similar levels of susceptibility to M. bovis infection.


Asunto(s)
Ciervos , Mycobacterium bovis , Tuberculosis Bovina/patología , Tuberculosis Ganglionar/veterinaria , Animales , Antígenos Bacterianos/biosíntesis , Bovinos , Femenino , Inmunidad Celular , Inmunoglobulina G/biosíntesis , Activación de Linfocitos , Masculino , Mycobacterium bovis/inmunología , Especificidad de la Especie , Prueba de Tuberculina , Tuberculosis Bovina/inmunología , Tuberculosis Ganglionar/inmunología , Tuberculosis Ganglionar/patología
15.
J Clin Pathol ; 59(7): 775-8, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16803953

RESUMEN

Primary primitive neuroectodermal tumours (PNETs) of the bladder are extremely rare and aggressive neoplasms, and only six examples have been reported in the literature. The case of a 21-year-old woman, who remains disease free 3 years after tumour resection, is reported here. Morphological features were found to correspond to a small round blue cell tumour without rosette formation and with extensive areas of necrosis. Strong expression of CD99, vimentin and CD117 (c-kit), and focal reactivity to cytokeratin and S-100 protein was observed in tumour cells. Ultrastructurally, sparse neurosecretory granules were observed. Diagnosis of PNET was supported by molecular genetic analysis, showing the EWS-FLI-1 fusion transcript type 2 by RT-PCR and EWS gene rearrangement by fluorescence in situ hybridisation. A normal genetically balanced genotype was shown by comparative genomic hybridisation, which, together with the expression of c-kit, a known therapeutic target for imatinib, may have prognostic and therapeutic implications.


Asunto(s)
Tumores Neuroectodérmicos Primitivos/patología , Neoplasias de la Vejiga Urinaria/patología , Adulto , Femenino , Humanos , Proteínas de Neoplasias/metabolismo , Tumores Neuroectodérmicos Primitivos/genética , Tumores Neuroectodérmicos Primitivos/metabolismo , Proteínas de Fusión Oncogénica/genética , Proteína Proto-Oncogénica c-fli-1/genética , Proteína EWS de Unión a ARN , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/metabolismo
16.
Onderstepoort J Vet Res ; 73(4): 293-303, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17283730

RESUMEN

An infection model for Mycobacterium bovis in African buffaloes, Syncerus caffer, was developed, using the intratonsilar route of inoculation. Two groups of 11 buffaloes each, aged approximately 18 months, were infected with either 3.2 x 10(2) cfu (low dose) or 3 x 10(4) cfu (high dose) of M. bovis strain isolated from a buffalo. A control group of six buffaloes received saline via the same route. The infection status was monitored in vivo using the comparative intradermal tuberculin test, and in vitro by the modified interferon-gamma assay. All buffaloes were euthanazed 22 weeks post infection and lesion development was assessed by macroscopic examination, culture and histopathology. It was found that the high dose caused macroscopic lesions in nine out of 11 buffaloes. Mycobacterium bovis was isolated from all buffaloes in the high-dose group and from six out of 11 in the low-dose group.


Asunto(s)
Búfalos/microbiología , Modelos Animales de Enfermedad , Mycobacterium bovis/patogenicidad , Tuberculosis Bovina/microbiología , Animales , Bovinos , Recuento de Colonia Microbiana/veterinaria , Interferón gamma/sangre , Mycobacterium bovis/inmunología , Tonsila Palatina/microbiología , Distribución Aleatoria , Especificidad de la Especie , Prueba de Tuberculina/veterinaria
17.
J Hosp Infect ; 92(3): 273-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26810613

RESUMEN

BACKGROUND: Hospital-acquired pneumonia (HAP) is defined as radiologically confirmed pneumonia occurring ≥48h after hospitalization, in non-intubated patients. Empirical treatment regimens use broad-spectrum antimicrobials. AIM: To evaluate the accuracy of the diagnosis of HAP and to describe the demographic and microbiological features of patients with HAP. METHODS: Medical and surgical inpatients receiving intravenous antimicrobials for a clinical diagnosis of HAP at a UK tertiary care hospital between April 2013 and 2014 were identified. Demographic and clinical details were recorded. FINDINGS: A total of 166 adult patients with a clinical diagnosis of HAP were identified. Broad-spectrum antimicrobials were prescribed, primarily piperacillin-tazobactam (57.2%) and co-amoxiclav (12.5%). Sputum from 24.7% of patients was obtained for culture. Sixty-five percent of patients had radiological evidence of new/progressive infiltrate at the time of HAP treatment, therefore meeting HAP diagnostic criteria (2005 American Thoracic Society/Infectious Diseases Society of America guidelines). Radiologically confirmed HAP was associated with higher levels of inflammatory markers and sputum culture positivity. Previous surgery and/or endotracheal intubation were associated with radiologically confirmed HAP. A bacterial pathogen was identified from 17/35 sputum samples from radiologically confirmed HAP patients. These were Gram-negative bacilli (N = 11) or Staphylococcus aureus (N = 6). Gram-negative bacteria tended to be resistant to co-amoxiclav, but susceptible to ciprofloxacin, piperacillin-tazobactam and meropenem. Five of the six S. aureus isolates were meticillin susceptible and all were susceptible to doxycycline. CONCLUSION: In ward-level hospital practice 'HAP' is an over-used diagnosis that may be inaccurate in 35% of cases when objective radiological criteria are applied. Radiologically confirmed HAP represents a distinct clinical and microbiological phenotype. Potential risk factors were identified that could represent targets for preventive interventions.


Asunto(s)
Infección Hospitalaria/diagnóstico , Infección Hospitalaria/patología , Pruebas Diagnósticas de Rutina , Pulmón/patología , Neumonía/diagnóstico , Neumonía/patología , Radiografía Torácica , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Estudios Retrospectivos , Centros de Atención Terciaria , Reino Unido
18.
N Z Vet J ; 64(3): 174-8, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26642120

RESUMEN

AIMS: To explore and validate the utility of rumen endoscopy for collection of rumen papillae for gene expression measurement. METHODS: Four adult Coopworth ewes were fasted for either 4 or 24 hours. Animals were sedated, placed in a dorsally recumbent position at 45 degrees with the head upright, and an endoscope inserted via a tube inserted into the mouth. Biopsies of rumen papillae were taken from the ventral surface of the rumen atrium under visual guidance. Two biopsies were collected from one of the animals that had been fasted for 4 hours, and three from one of the animals that had been fasted for 24 hours. Video of the rumen atrium and reticulum was also collected. The animals recovered uneventfully. Biopsies were subsequently used for extraction and sequencing of mRNA. RESULTS: The ventral surface of the rumen atrium was accessible after 4 hours off pasture, but a larger region was accessible after 24 hours of fasting. Sedation allowed access for endoscope use for around 5 to 10 minutes after which increased saliva flow was noted. Rumen papillae biopsies were easily collected, with samples from a variety of sites collected in the ∼10 minute time window. High quality RNA was obtained for stranded mRNA sequencing. Of the resulting reads, 69-70% mapped uniquely to version 3.1 of the ovine genome, and 48-49% to a known gene. The rumen mRNA profiles were consistent with a previously reported study. CONCLUSIONS: This method for obtaining rumenal tissue was found to be rapid and resulted in no apparent short or long term effects on the animal. High quality RNA was successfully extracted and amplified from the rumen papillae biopsies, indicating that this technique could be used for future gene expression studies. The use of rumen endoscopy could be extended to collection of a variety of rumen and reticulum anatomical measurements and deposition and retrieval of small sensors from the rumen. Rumen endoscopy offers an attractive and cost effective approach to repeated rumen biopsies compared with serial slaughter or use of cannulated animals.


Asunto(s)
Endoscopía Gastrointestinal/veterinaria , Rumen/patología , Ovinos , Animales , Biopsia/métodos , Biopsia/veterinaria , Endoscopía Gastrointestinal/métodos , Femenino
19.
Vet Immunol Immunopathol ; 169: 102-10, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26620077

RESUMEN

This study compared in vivo lymph node gene expression levels between six young red deer that were either relatively resistant (R) or susceptible (S) to paratuberculosis following experimental challenge with Mycobacterium avium subsp. paratuberculosis. Intestinal lymph nodes were biopsied at 4, 12 and 50 weeks post challenge (pc) and parallel changes in histopathology, immunology and bacterial load monitored. SOLiD SAGE (serial analysis of gene expression) next generation sequencing of biopsied lymph node samples generated a total of 373 million transcript tags 26-28bp in length after filtering. A total of 36,632 unique transcripts were identified and 14,325 of these were able to be annotated. The copy number of each transcript was counted, averaged and compared for R and S animals (R-S). P values and False Discovery Rates (FDR) were calculated for each transcript. Genes differentially upregulated ≥2 fold (FDR<0.5) totalled 9, 40 and 32 in R animals (+ values) and 23, 164 and 47 in S animals (- values) at weeks 4, 12, and 50pc, respectively. Transcripts displaying greatest differential expression between R and S animals at each time point were IFIT2 (189 fold) and S100A8 (-32.7 fold) at week 4, LRR1 (52.7 fold), SERPINF2 (-214.6 fold) at week 12 and CEACAM8 (84.6 fold), and STK31 (-129.5 fold) at week 50, respectively. All 9 genes significantly upregulated at week 4 in R animals relate specifically to host defence and all involve Type I interferon stimulated genes. By contrast genes upregulated in S animals at week 4, relate predominantly to inflammation, but also involve adaptive immune responses, mitochondrial function and apoptosis regulation. At week 12, the genes differentially upregulated in R animals are linked predominantly to regulation of adaptive immunity and mucosal immunity, while many of the genes in S animals are associated with pro-inflammatory interleukins involved with innate and adaptive immunity. These correlated with greater lesion severity and higher MAP numbers in lymph nodes of S animals. By week 50 the number of upregulated genes declined in both groups. A number of genes upregulated in R animals appear to be associated with host resistance and regulation of adaptive immunity, especially CEACAM8. Genes upregulated in S animals involve antigen presentation (ENDOD1) and gut associated immune pathology (HSH2D). In conclusion, gene expression in jejunal lymph nodes of resistant and susceptible deer infer that the resistant phenotype is associated with pathways of adaptive immunity, while susceptibility is linked with upregulated non-protective pro-inflammatory responses, following experimental MAP infection.


Asunto(s)
Ciervos/microbiología , Yeyuno/metabolismo , Mycobacterium avium subsp. paratuberculosis , Paratuberculosis/genética , Animales , Ciervos/inmunología , Resistencia a la Enfermedad/genética , Expresión Génica , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Predisposición Genética a la Enfermedad , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/metabolismo , Paratuberculosis/inmunología , Regulación hacia Arriba
20.
Trends Microbiol ; 3(11): 418-24, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8574514

RESUMEN

While the etiology of tuberculosis is well understood, the nature of the protective immune response to the causative mycobacteria has remained a mystery. There is an urgent need to define protective immunity critically, and to develop alternative animal models to evaluate the efficacy of new-generation vaccines against tuberculosis in a cost-effective way.


Asunto(s)
Vacuna BCG/inmunología , Tuberculosis/prevención & control , Animales , Modelos Animales de Enfermedad , Humanos , Inmunidad , Mycobacterium bovis/inmunología , Mycobacterium tuberculosis/inmunología , Tuberculosis/inmunología
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