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1.
BMC Vet Res ; 11: 29, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25880998

RESUMO

BACKGROUND: Vaccination of young calves against Bovine viral diarrhea virus (BVDV) is desirable in dairy and beef operations to reduce clinical disease and prevent spread of the virus among cattle. Although protection from clinical disease by multivalent, modified-live virus (MLV) vaccines has been demonstrated, the ability of MLV vaccines to prevent viremia and viral shedding in young calves possessing passive immunity is not known. The purpose of this study was to compare the ability of three different MLV vaccines to prevent clinical disease, viremia, and virus shedding in early weaned beef calves possessing maternal immunity that were vaccinated once at 45 days prior to challenge with virulent BVDV 2. RESULTS: At 45 days following vaccination, calves that received vaccines B and C had significantly higher BVDV 1 and BVDV 2 serum antibody titers compared with control calves. Serum antibody titers for BVDV 1 and BVDV 2 were not significantly different between control calves and calves that received vaccine D. Following BVDV 2 challenge, a higher proportion of control calves and calves that received vaccine D presented viremia and shed virus compared with calves that received vaccines B and C. Rectal temperatures and clinical scores were not significantly different between groups at any time period. Calves that received vaccines B and C had significantly higher mean body weights at BVDV 2 challenge and at the end of the study compared with control calves. CONCLUSIONS: Moderate to low maternally-derived BVDV antibody levels protected all calves against severe clinical disease after challenge with virulent BVDV 2. Vaccines B and C induced a greater antibody response to BVDV 1 and BVDV 2, and resulted in reduced viremia and virus shedding in vaccinated calves after challenge indicating a greater efficacy in preventing virus transmission and reducing negative effects of viremia.


Assuntos
Doença das Mucosas por Vírus da Diarreia Viral Bovina/prevenção & controle , Vírus da Diarreia Viral Bovina Tipo 2/patogenicidade , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Doença das Mucosas por Vírus da Diarreia Viral Bovina/sangue , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Bovinos , Virulência
2.
Vet Res ; 45: 38, 2014 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-24708266

RESUMO

Infections with bovine viral diarrhea virus (BVDV) of the genus pestivirus, family Flaviviridae, are not limited to cattle but occur in various artiodactyls. Persistently infected (PI) cattle are the main source of BVDV. Persistent infections also occur in heterologous hosts such as sheep and deer. BVDV infections of goats commonly result in reproductive disease, but viable PI goats are rare. Using 2 BVDV isolates, previously demonstrated to cause PI cattle and white-tailed deer, this study evaluated the outcome of experimental infection of pregnant goats. Pregnant goats (5 goats/group) were intranasally inoculated with BVDV 1b AU526 (group 1) or BVDV 2 PA131 (group 2) at approximately 25-35 days of gestation. The outcome of infection varied considerably between groups. In group 1, only 3 does became viremic, and 1 doe gave birth to a stillborn fetus and a viable PI kid, which appeared healthy and shed BVDV continuously. In group 2, all does became viremic, 4/5 does aborted, and 1 doe gave birth to a non-viable PI kid. Immunohistochemistry demonstrated BVDV antigen in tissues of evaluated fetuses, with similar distribution but reduced intensity as compared to cattle. The genetic sequence of inoculated viruses was compared to those from PI kids and their dam. Most nucleotide changes in group 1 were present during the dam's acute infection. In group 2, a similar number of mutations resulted from fetal infection as from maternal acute infection. Results demonstrated that BVDV may cause reproductive disease but may also be maintained in goats.


Assuntos
Aborto Animal/virologia , Vírus da Diarreia Viral Bovina Tipo 1/fisiologia , Vírus da Diarreia Viral Bovina Tipo 2/fisiologia , Doenças das Cabras/virologia , Infecções por Pestivirus/veterinária , Complicações Infecciosas na Gravidez/veterinária , Feto Abortado/virologia , Animais , Antígenos Virais/metabolismo , Vírus da Diarreia Viral Bovina Tipo 1/genética , Vírus da Diarreia Viral Bovina Tipo 2/genética , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Idade Gestacional , Cabras , Imuno-Histoquímica/veterinária , Masculino , Dados de Sequência Molecular , Infecções por Pestivirus/complicações , Infecções por Pestivirus/virologia , Gravidez , Complicações Infecciosas na Gravidez/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Análise de Sequência de DNA/veterinária , Viremia/veterinária , Viremia/virologia
3.
New Phytol ; 197(1): 73-87, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23126654

RESUMO

Disrupting pollen tube growth and fertilization in Arabidopsis plants leads to reduced seed set and silique size, providing a powerful genetic system with which to identify genes with important roles in plant fertility. A transgenic Arabidopsis line with reduced pollen tube growth, seed set and silique growth was used as the progenitor in a genetic screen to isolate suppressors with increased seed set and silique size. This screen generated a new allele of INDEHISCENT (IND), a gene originally identified by its role in valve margin development and silique dehiscence (pod shatter). IND forms part of a regulatory network that involves several other transcriptional regulators and involves the plant hormones GA and auxin. Using GA and auxin mutants that alter various aspects of reproductive development, we have identified novel roles for IND, its paralogue HECATE3, and the MADS box proteins SHATTERPROOF1/2 in flower and fruit development. These results suggest that modified forms of the regulatory network originally described for the Arabidopsis valve margin, which include these genes and/or their recently evolved paralogs, function in multiple components of GA/auxin-regulated reproductive development.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Redes Reguladoras de Genes , Sementes/crescimento & desenvolvimento , Alelos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Arginina/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fertilidade , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/metabolismo , Filogenia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Tubo Polínico/genética , Tubo Polínico/crescimento & desenvolvimento , Tubo Polínico/metabolismo , Polinização , Estabilidade Proteica , Reprodução , Sementes/genética , Sementes/metabolismo , Autofertilização , Transcrição Gênica
4.
J Environ Manage ; 101: 92-103, 2012 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-22406849

RESUMO

Discolouration of natural surface waters due to the humic component of dissolved organic carbon (DOC) is a costly problem for water supply companies. This paper reviews what is known about the impacts of prescribed moorland vegetation burning on water colour. Relevant research has taken place at three scales: laboratory experiments on peat cores, plot scale sampling of soil waters and catchment scale sampling of stream waters. While laboratory studies suggest burning increases colour production, the evidence from catchment and plot studies is contradictory. Plot studies suggest colour production may decrease or remain unchanged following burning although there is evidence for some transient changes. Catchment studies suggest prescribed moorland burning causes stream water colour to increase, although in most cases the evidence is not clear cut since most studies could not clearly disentangle the effects of burning from those of vegetation cover. The differences in findings between plot and catchment studies may be explained by: i) the short-term nature of some studies which do not measure long-term response and recovery times to burning; ii) the lack of colour measurements from shallow soil depths which contribute more to streamflow than soil water from deeper in the peat; and iii) the possibility of hydrological interactions occurring between different experimental plots at some sites. Additionally, the increase in recent patch burning in some catchments that has been statistically attributed by some authors to increases in stream water colour cannot be reconciled with theoretical calculations. When dilution with waters derived from other parts of the catchment are taken into account, large values of colour have to be theoretically derived from those recently burnt areas that occupy a small proportion of the catchment area in order to balance the change in stream water colour observed in recent years. Therefore, much further process-based work is required to properly investigate whether prescribed vegetation burning is a direct driver of enhanced colour and DOC in upland streams, rivers and lakes.


Assuntos
Cor , Incêndios , Água Doce , Qualidade da Água , Carbono , Água Subterrânea , Lagos , Rios , Solo
5.
Appl Environ Microbiol ; 77(2): 684-7, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21097590

RESUMO

The levels of integron abundance and diversity in soil amended with pig slurry were studied. Real-time PCR illustrated a significant increase in class 1 integron prevalence after slurry application, with increased prevalence still evident at 10 months after application. Culture-dependent data revealed 10 genera, including putative human pathogens, carrying class 1 and 2 integrons.


Assuntos
Variação Genética , Integrons , Esterco/microbiologia , Metagenoma , Microbiologia do Solo , Agricultura/métodos , Animais , Bactérias/classificação , Bactérias/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Prevalência , Análise de Sequência de DNA , Suínos
6.
Proc Natl Acad Sci U S A ; 105(47): 18221-5, 2008 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-19015521

RESUMO

Categorical perception (CP) of color is the faster and more accurate discrimination of two colors from different categories than two colors from the same category, even when same- and different-category chromatic separations are equated. In adults, color CP is lateralized to the left hemisphere (LH), whereas in infants, it is lateralized to the right hemisphere (RH). There is evidence that the LH bias in color CP in adults is due to the influence of color terms in the LH. Here we show that the RH to LH switch in color CP occurs when the words that distinguish the relevant category boundary are learned. A colored target was shown in either the left- or right-visual field on either the same- or different-category background, with equal hue separation for both conditions. The time to initiate an eye movement toward the target from central fixation at target onset was recorded. Color naming and comprehension was assessed. Toddlers were faster at detecting targets on different- than same-category backgrounds and the extent of CP did not vary with level of color term knowledge. However, for toddlers who knew the relevant color terms, the category effect was found only for targets in the RVF (LH), whereas for toddlers learning the color terms, the category effect was found only for targets in the LVF (RH). The findings suggest that lateralization of color CP changes with color term acquisition, and provide evidence for the influence of language on the functional organization of the brain.


Assuntos
Percepção de Cores , Adulto , Pré-Escolar , Humanos , Lactente , Campos Visuais
7.
Proc Natl Acad Sci U S A ; 105(9): 3221-5, 2008 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-18316729

RESUMO

Both adults and infants are faster at discriminating between two colors from different categories than two colors from the same category, even when between- and within-category chromatic separation sizes are equated. For adults, this categorical perception (CP) is lateralized; the category effect is stronger for the right visual field (RVF)-left hemisphere (LH) than the left visual field (LVF)-right hemisphere (RH). Converging evidence suggests that the LH bias in color CP in adults is caused by the influence of lexical color codes in the LH. The current study investigates whether prelinguistic color CP is also lateralized to the LH by testing 4- to 6-month-old infants. A colored target was shown on a differently colored background, and time to initiate an eye movement to the target was measured. Target background pairs were either from the same or different categories, but with equal target-background chromatic separations. Infants were faster at initiating an eye movement to targets on different-category than same-category backgrounds, but only for targets in the LVF-RH. In contrast, adults showed a greater category effect when targets were presented to the RVF-LH. These results suggest that whereas color CP is stronger in the LH than RH in adults, prelinguistic CP in infants is lateralized to the RH. The findings suggest that language-driven CP in adults may not build on prelinguistic CP, but that language instead imposes its categories on a LH that is not categorically prepartitioned.


Assuntos
Percepção de Cores/fisiologia , Lateralidade Funcional/fisiologia , Adulto , Fatores Etários , Humanos , Lactente , Idioma , Tempo de Reação , Campos Visuais
8.
J Marital Fam Ther ; 47(1): 69-84, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33161620

RESUMO

Common factors proponents have suggested the need for principle-based meta-models to explain how various factors interact with each other to produce change. The therapeutic pyramid is a common factors meta-model that outlines how therapeutic skills and techniques, the therapeutic alliance, and a therapist's way of being interactive to produce therapeutic change. Skills and techniques occupy the smallest top portion of the pyramid, with the therapeutic alliance in the middle and a therapist's way of being forming the foundation of the pyramid. The success of any layer rests on the quality of the immediately underlying layer. This study illustrates the broad applicability of common factors meta-models by applying the therapeutic pyramid to couples therapy, family therapy, training and supervision, and professional ethics.


Assuntos
Terapia de Casal/métodos , Terapia Familiar/métodos , Modelos Teóricos , Terapia de Casal/educação , Ética Profissional , Terapia Familiar/educação , Humanos , Relações Pais-Filho , Competência Profissional
9.
J Exp Med ; 168(3): 933-40, 1988 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-3171479

RESUMO

The genomic organization of the human MHC was examined in multiple examples of six different supratypes using pulsed field electrophoresis (PFGE) after digestion of genomic DNA with infrequency cutting restriction endonucleases. Differences in restriction fragment length and band intensity were shown to be specific for each supratype. Mapping of the MHC revealed that each supratype contains previously undescribed deletions and insertions between HLA B and DQ regions.


Assuntos
Cromossomos Humanos Par 6 , Eletroforese em Gel de Ágar/métodos , Eletroforese/métodos , Complexo Principal de Histocompatibilidade , Deleção Cromossômica , Mapeamento Cromossômico , Humanos , Família Multigênica , Mapeamento por Restrição
10.
Int Orthop ; 34(4): 505-10, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19458950

RESUMO

We describe the results of a retrospective analysis of patients with microbiologically proven infection, who underwent revision TKA between 1994 and 2008. Of the 121 patients included in the study, 61 (50%) were male and 60 (50%) were female. The mean age was 71 (range 42-88) years. The most common organisms identified were Coagulase negative Staphylococcus (CNS) (49%) and Staphylococcus aureus (SA) (13%). The prevalence of CNS appears to be increasing, while that of SA and other organisms is decreasing. Vancomycin and teicoplanin were the most effective antibiotics with overall sensitivity rates of 100% and 96%, respectively. The results of our theoretical model suggest that gentamicin combined with vancomycin is the most effective empirical regimen. Staphylococcal species are the most common organisms encountered in deep infection of the knee. Gentamicin combined with vancomycin offers the most comprehensive protection and potentially allows for infected knee arthoplasties to be treated with a one-stage procedure.


Assuntos
Artroplastia do Joelho/efeitos adversos , Articulação do Joelho/microbiologia , Infecções Relacionadas à Prótese/microbiologia , Infecção da Ferida Cirúrgica/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Coagulase/metabolismo , Quimioterapia Combinada , Feminino , Gentamicinas/uso terapêutico , Humanos , Articulação do Joelho/patologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/diagnóstico , Infecções Relacionadas à Prótese/tratamento farmacológico , Reoperação , Estudos Retrospectivos , Infecções Estafilocócicas/diagnóstico , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Staphylococcus/efeitos dos fármacos , Staphylococcus/enzimologia , Staphylococcus/isolamento & purificação , Infecção da Ferida Cirúrgica/diagnóstico , Infecção da Ferida Cirúrgica/tratamento farmacológico , Resultado do Tratamento , Vancomicina/uso terapêutico
11.
Data Brief ; 28: 104836, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31871984

RESUMO

The present data article is based on the research work which investigates the influence of blends of diesel and renewable fuels on compression ignition engine emissions. In this experimental work, a 2.4 L, turbocharged, direct injection compression ignition engine and water brake dynamometer were used. Different ternary blends were created by mixing diesel, biodiesel and ethanol together in accordance with a mixture design of experiments. The homogeneity of each ternary blend was qualitatively checked by observing the samples for 24 hours for visible separation. The engine was run over the WLTP drive cycle for each individual ternary blend and the exhaust emissions were recorded. NOVA 7466K and TESTO 350 gas analysers were used to record the exhaust emissions. A factory standard MAF sensor was used to record the inlet air mass flow and an aftermarket ECU was used to determine the fuel flow. The ternary blends were blended using standard laboratory measuring equipment.

12.
Front Microbiol ; 11: 1138, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32587582

RESUMO

Bovine viral diarrhea virus (BVDV) is one of the most economically important viruses of cattle, but this pathogen is also able to infect pigs, camelids, and a wide range of domestic and wild ruminants. BVDV isolates circulating in animal populations are genetically and antigenically highly diverse. Acute BVDV infections in cattle cause the introduction of many substitutions in the viral genome. Serial infection of pregnant sheep with a BVDV-1b isolate of bovine origin was also associated with great numbers of substitutions. To our knowledge, genomic changes arising during BVDV infections in swine have not been investigated. The purpose of this study was to investigate the changes occurring in the open reading frame (ORF) of BVDV during serial infection of pregnant swine with a BVDV isolate of bovine origin. The BVDV-1b isolate AU526 was serially passaged in six pregnant gilts, two of which gave birth to live piglets congenitally infected with BVDV. The complete ORF sequences of 14 BVDV isolates obtained from pregnant gilts and their piglets were determined. Their analysis revealed that serial transmission of AU526 in pregnant swine resulted in many genomic changes. All isolates of porcine origin shared 32 nucleotide and 12 amino acid differences with the virus inoculum AU526. These changes were detected after a single passage in pregnant swine and were conserved during the subsequent five passages. Amino acid changes occurred primarily in genomic regions encoding the BVDV structural proteins E2 and E rns . These results suggest that BVDV infections in pregnant swine may contribute significantly to the genetic variability of BVDV and lead to the appearance of adaptive changes.

13.
Sci Transl Med ; 12(568)2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-33148623

RESUMO

Acute bacterial endocarditis is a rapid, difficult to manage, and frequently lethal disease. Potent antibiotics often cannot efficiently kill Staphylococcus aureus that colonizes the heart's valves. S. aureus relies on virulence factors to evade therapeutics and the host's immune response, usurping the host's clotting system by activating circulating prothrombin with staphylocoagulase and von Willebrand factor-binding protein. An insoluble fibrin barrier then forms around the bacterial colony, shielding the pathogen from immune cell clearance. Targeting virulence factors may provide previously unidentified avenues to better diagnose and treat endocarditis. To tap into this unused therapeutic opportunity, we codeveloped therapeutics and multimodal molecular imaging to probe the host-pathogen interface. We introduced and validated a family of small-molecule optical and positron emission tomography (PET) reporters targeting active thrombin in the fibrin-rich environment of bacterial colonies. The imaging agents, based on the clinical thrombin inhibitor dabigatran, are bound to heart valve vegetations in mice. Using optical imaging, we monitored therapy with antibodies neutralizing staphylocoagulase and von Willebrand factor-binding protein in mice with S. aureus endocarditis. This treatment deactivated bacterial defenses against innate immune cells, decreased in vivo imaging signal, and improved survival. Aortic or tricuspid S. aureus endocarditis in piglets was also successfully imaged with clinical PET/magnetic resonance imaging. Our data map a route toward adjuvant immunotherapy for endocarditis and provide efficient tools to monitor this drug class for infectious diseases.


Assuntos
Endocardite Bacteriana , Infecções Estafilocócicas , Animais , Coagulase , Endocardite Bacteriana/diagnóstico por imagem , Endocardite Bacteriana/tratamento farmacológico , Camundongos , Imagem Multimodal , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus , Suínos
14.
Antimicrob Agents Chemother ; 53(2): 696-702, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19064898

RESUMO

The prevalences of three sulfonamide resistance genes, sul1, sul2, and sul3 and sulfachloropyridazine (SCP) resistance were determined in bacteria isolated from manured agricultural clay soils and slurry samples in the United Kingdom over a 2-year period. Slurry from tylosin-fed pigs amended with SCP and oxytetracycline was used for manuring. Isolates positive for sul genes were further screened for the presence of class 1 and 2 integrons. Phenotypic resistance to SCP was significantly higher in isolates from pig slurry and postapplication soil than in those from preapplication soil. Of 531 isolates, 23% carried sul1, 18% sul2, and 9% sul3 only. Two percent of isolates contained all three sul genes. Class 1 and class 2 integrons were identified in 5% and 11.7%, respectively, of sul-positive isolates. In previous reports, sul1 was linked to class 1 integrons, but in this study only 8% of sul1-positive isolates carried the intI1 gene. Sulfonamide-resistant pathogens, including Shigella flexneri, Aerococcus spp., and Acinetobacter baumannii, were identified in slurry-amended soil and soil leachate, suggesting a potential environmental reservoir. Sulfonamide resistance in Psychrobacter, Enterococcus, and Bacillus spp. is reported for the first time, and this study also provides the first description of the genotypes sul1, sul2, and sul3 outside the Enterobacteriaceae and in the soil environment.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Esterco/microbiologia , Esgotos/microbiologia , Microbiologia do Solo , Sulfonamidas/farmacologia , Animais , Contagem de Colônia Microbiana , Conjugação Genética , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Integrons/genética , Testes de Sensibilidade Microbiana , Oxitetraciclina/farmacologia , RNA Ribossômico/genética , Suínos , Tilosina/farmacologia , Reino Unido
15.
J Environ Manage ; 90(11): 3512-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19576680

RESUMO

In recent years there has been a dramatic increase in artificial drain-blocking in world peatlands. The UK blanket peatlands have been severely drained over the past few decades but now drains are being blocked in an attempt to improve peatland environments. The drain-blocking has been a disparate process with limited knowledge transfer between organisations and within organisations operating in different geographic areas. Consequently, there has been no compilation of techniques used and their effectiveness. During this study thirty-two drain-blocked sites were surveyed and all the key stakeholders interviewed. Drain-blocking using peat turf was preferred by practitioners and was also the most cost-effective method. Peat turves were successful except on steep slopes, in areas of severe erosion, in very wet or very dry locations, or if the mineral substrate was exposed. A drain-blocking best practice guide is offered by this paper, providing information on the most suitable methods for blocking peatland drains under different circumstances. Additional considerations are provided for practitioners to ensure peatland drain-blocking is as successful as possible.


Assuntos
Conservação dos Recursos Naturais/métodos , Solo , Movimentos da Água , Monitoramento Ambiental
16.
Oncogene ; 26(3): 368-81, 2007 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-16847455

RESUMO

Leucine-rich repeats and immunoglobulin-like domains-1 (LRIG1) is a transmembrane protein with an ectodomain containing 15 leucine-rich repeats (LRRs) homologous to mammalian decorin and the Drosophila kekkon1 gene. In this study, we demonstrate that a soluble ectodomain of LRIG1, containing only the LRRs, inhibits ligand-independent epidermal growth factor receptor (EGFR) activation and causes growth inhibition of A431, HeLa and MDA-468 carcinoma cells. In contrast, cells that do not express detectable levels of EGFR fail to respond to soluble LRIG1. However, when a functional EGFR gene is introduced in these cells, they become growth-inhibited by soluble LRIG1 protein. Furthermore, we demonstrate the existence of high-affinity (K(d)=10 nM) binding sites on the A431 cells that can be competitively displaced (up to 75%) by molar excess of EGF. Even more powerful effects are obtained with a chimeric proteoglycan harboring the N-terminus of decorin, substituted with a single glycosaminoglycan chain, fused to the LRIG1 ectodomain. Both proteins also inhibit ligand-dependent activation of the EGFR and extracellular signal-regulated protein kinase 1/2 signaling in a rapid and dose-dependent manner. These results suggest a novel mechanism of action evoked by a soluble ectodomain of LRIG1 protein that could modulate EGFR signaling and its growth-promoting activity. Attenuation of EGFR activity without physical downregulation of the receptor could represent a novel therapeutic approach toward malignancies in which EGFR plays a primary role in tumor growth and survival.


Assuntos
Receptores ErbB/metabolismo , Regulação da Expressão Gênica/fisiologia , Glicoproteínas de Membrana/genética , Sequência de Aminoácidos , Animais , Sítios de Ligação , Células CHO , Proliferação de Células , Cricetinae , Cricetulus , Decorina , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Genes Dominantes , Células HeLa , Humanos , Ligantes , Dados de Sequência Molecular , Ligação Proteica , Proteoglicanas/genética , Proteoglicanas/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Transdução de Sinais , Células Tumorais Cultivadas/metabolismo , Células Tumorais Cultivadas/patologia
17.
J Bone Joint Surg Br ; 90(6): 821-4, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18539680

RESUMO

In order to investigate the osteoinductive properties of allograft used in impaction grafting and the effect of strain during impaction on these properties, we designed an in vitro experiment to measure strain-related release of bone morphogenetic protein-7 (BMP-7) from fresh-frozen femoral head allograft. A total of 40 10 mm cubes of cancellous bone were cut from ten samples of fresh-frozen femoral head. The marrow was removed from the cubes and the baseline concentrations of BMP-7 were measured. Specimens from each femoral head were allocated to four groups and subjected to different compressive strains with a material testing machine, after which BMP-7 activity was reassessed. It was present in all groups. There was a linear increase of 102.1 pg/g (95% confidence interval 68.6 to 135.6) BMP-7 for each 10% increase in strain. At 80% strain the mean concentration of BMP-7 released (830.3 pg/g bone) was approximately four times that released at 20% strain. Activity of BMP-7 in fresh-frozen allograft has not previously been demonstrated. This study shows that the freezing and storage of femoral heads allows some maintenance of biological activity, and that impaction grafting provides a source of osteoinductive bone for remodelling. We have shown that BMP-7 is released from fresh-frozen femoral head cancellous bone in proportion to the strain applied to the bone. This suggests that the impaction process itself may contribute to the biological process of remodelling and bony incorporation.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Transplante Ósseo/métodos , Cabeça do Fêmur/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Proteína Morfogenética Óssea 7 , Remodelação Óssea/fisiologia , Criopreservação , Cabeça do Fêmur/transplante , Humanos , Técnicas In Vitro , Estresse Mecânico
18.
Theriogenology ; 70(2): 153-60, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18452983

RESUMO

The objective of this study was to develop a duplex quantitative polymerase chain reaction (qPCR) assay for simultaneous detection of bovine herpesvirus 1 (BoHV-1) and bovine viral diarrhea virus (BVDV) type I and type II. Follicular fluid was collected from a BoHV-1 acutely infected heifer, a BVDV I persistently infected heifer, and from 10 ovaries recovered from an abattoir. Both the BoHV-1 and BVDV contaminated follicular fluid were diluted 1:5 to 1:10(7) using the pooled, abattoir-origin follicular fluid. Each dilution sample was analyzed using the duplex qPCR, virus isolation, reverse transcription-nested PCR (RT-nPCR), and BoHV-1 qPCR. The duplex qPCR was able to simultaneously detect BoHV-1 and BVDV I in the fluid diluted to 1:100 and 1:1000, respectively. These results corresponded with the reverse transcription-nested PCR and BoHV-1 qPCR. Therefore, the duplex qPCR might be used for quality assurance testing to identify these two viruses in cells, fluids and tissues collected from donor animals and used in reproductive technologies.


Assuntos
Vírus da Diarreia Viral Bovina/isolamento & purificação , Líquido Folicular/virologia , Herpesvirus Bovino 1/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Animais , Doença das Mucosas por Vírus da Diarreia Viral Bovina/virologia , Bovinos , Feminino , Rinotraqueíte Infecciosa Bovina/virologia
19.
Med Klin (Munich) ; 103(5): 346-8, 2008 May 15.
Artigo em Alemão | MEDLINE | ID: mdl-18484221

RESUMO

BACKGROUND: Campylobacter-jejuni infection can lead to different extraintestinal manifestations. Myo-/pericarditis and toxic hepatitis have been reported. A combined appearance has not been described yet. CASE REPORT: A 22-year-old woman presented with sudden left thoracic pain. An increase in troponin T, creatine kinase and myoglobin was noted. In the absence of signs of myocardial ischemia, the diagnosis of myocarditis was made. The patient reported diarrhea persisting for 5 days. Campylobacter-jejuni could be identified in the feces. On account of rising transaminases, a biopsy of the liver was performed. The histological examination revealed lesions caused by Campylobacter-jejuni. CONCLUSION: Given the increasing incidence of Campylobacter-jejuni infections, the case presented here should draw the attention to extraintestinal manifestations.


Assuntos
Infecções por Campylobacter/diagnóstico , Campylobacter jejuni , Enterite/diagnóstico , Hepatite A/diagnóstico , Miocardite/diagnóstico , Adulto , Biópsia , Infecções por Campylobacter/patologia , Dor no Peito/etiologia , Diagnóstico Diferencial , Enterite/patologia , Fezes/microbiologia , Feminino , Hepatite A/patologia , Humanos , Fígado/patologia , Testes de Função Hepática , Miocardite/patologia
20.
Bone Joint J ; 100-B(1): 20-27, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29305446

RESUMO

AIMS: The aim of this study was to determine whether patients with metal-on-metal (MoM) arthroplasties of the hip have an increased risk of cardiac failure compared with those with alternative types of arthroplasties (non-MoM). PATIENTS AND METHODS: A linkage study between the National Joint Registry, Hospital Episodes Statistics and records of the Office for National Statistics on deaths was undertaken. Patients who underwent elective total hip arthroplasty between January 2003 and December 2014 with no past history of cardiac failure were included and stratified as having either a MoM (n = 53 529) or a non-MoM (n = 482 247) arthroplasty. The primary outcome measure was the time to an admission to hospital for cardiac failure or death. Analysis was carried out using data from all patients and from those matched by propensity score. RESULTS: The risk of cardiac failure was lower in the MoM cohort compared with the non-MoM cohort (adjusted hazard ratio (aHR) 0.901; 95% confidence interval (CI) 0.853 to 0.953). The risk of cardiac failure was similar following matching (aHR 0.909; 95% CI 0.838 to 0.987) and the findings were consistent in subgroup analysis. CONCLUSION: The risk of cardiac failure following total hip arthroplasty was not increased in those in whom MoM implants were used, compared with those in whom other types of prostheses were used, in the first seven years after surgery. Cite this article: Bone Joint J 2018;100-B:20-7.


Assuntos
Artroplastia de Quadril/efeitos adversos , Insuficiência Cardíaca/etiologia , Prótese de Quadril/efeitos adversos , Próteses Articulares Metal-Metal/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/instrumentação , Artroplastia de Quadril/mortalidade , Feminino , Insuficiência Cardíaca/epidemiologia , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Registro Médico Coordenado , Pessoa de Meia-Idade , Desenho de Prótese , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Reino Unido/epidemiologia
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