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1.
J Small Anim Pract ; 64(9): 574-580, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37211353

RESUMO

OBJECTIVES: Exercise-induced gastrointestinal syndrome occurs in dogs and people and might compromise athlete performance by increasing intestinal permeability and causing gastrointestinal erosions. Racing sled dogs often receive acid suppressant prophylaxis which decreases the incidence of gastric erosions induced by exercise. The objectives were to quantify intestinal injury by measuring serum pro-inflammatory cytokine concentrations before and after exercise and to evaluate gastrointestinal mucosa using video capsule endoscopy after exercise. MATERIALS AND METHODS: Prospective study of 12 racing Alaskan sled dogs receiving approximately 1 mg/kg omeprazole once daily from the day before the race until race completion. Blood was drawn before and 8 to 10 hours after an endurance race for the quantification of cytokines. Gastrointestinal tract mucosa was assessed with video capsule endoscopy immediately post-race. RESULTS: Eight of nine dogs (89%; 95% confidence interval 52 to 100%) had gastric erosions; all dogs (100%, 95% confidence interval 63 to 100%) had small intestinal erosions. Most of the dogs (seven of nine) had straw or foreign material present. Cytokine levels were not different from before to after the race. CLINICAL SIGNIFICANCE: Video capsule endoscopy identified gastrointestinal tract mucosal erosions after exercise in all dogs receiving once-daily omeprazole treatment, though other causes for the lesions besides exercise are possible.


Assuntos
Endoscopia por Cápsula , Condicionamento Físico Animal , Cães , Animais , Endoscopia por Cápsula/veterinária , Estudos Prospectivos , Citocinas , Omeprazol/uso terapêutico , Intestino Delgado , Condicionamento Físico Animal/efeitos adversos
2.
PLoS One ; 16(9): e0256919, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34473784

RESUMO

Structured protocols offer a transparent and systematic way to elicit and combine/aggregate, probabilistic predictions from multiple experts. These judgements can be aggregated behaviourally or mathematically to derive a final group prediction. Mathematical rules (e.g., weighted linear combinations of judgments) provide an objective approach to aggregation. The quality of this aggregation can be defined in terms of accuracy, calibration and informativeness. These measures can be used to compare different aggregation approaches and help decide on which aggregation produces the "best" final prediction. When experts' performance can be scored on similar questions ahead of time, these scores can be translated into performance-based weights, and a performance-based weighted aggregation can then be used. When this is not possible though, several other aggregation methods, informed by measurable proxies for good performance, can be formulated and compared. Here, we develop a suite of aggregation methods, informed by previous experience and the available literature. We differentially weight our experts' estimates by measures of reasoning, engagement, openness to changing their mind, informativeness, prior knowledge, and extremity, asymmetry or granularity of estimates. Next, we investigate the relative performance of these aggregation methods using three datasets. The main goal of this research is to explore how measures of knowledge and behaviour of individuals can be leveraged to produce a better performing combined group judgment. Although the accuracy, calibration, and informativeness of the majority of methods are very similar, a couple of the aggregation methods consistently distinguish themselves as among the best or worst. Moreover, the majority of methods outperform the usual benchmarks provided by the simple average or the median of estimates.


Assuntos
Agregação de Dados , Prova Pericial , Processos Grupais , Julgamento , Modelos Estatísticos , Conscientização , Teorema de Bayes , Previsões/métodos , Humanos , Psicologia/métodos , Opinião Pública , Pesquisadores/psicologia , Estudantes/psicologia
3.
Oral Oncol ; 99: 104464, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31683172

RESUMO

OBJECTIVES: Compare length of stay, flap failure rate, medical and surgical complications and cost when patients undergoing head and neck free flap reconstruction are monitored in an intensive care unit (ICU) versus a specialty ward unit postoperatively. MATERIALS AND METHODS: A prospective, non-inferiority, randomized controlled trial was conducted from 7/22/2016 to 9/12/2018 at a single institution. Patients were randomized to the ICU or specialty ward unit. Flap check protocols were identical between the groups. Perioperative and postoperative outcome variables were assessed and compared. RESULTS: 131 patients were enrolled in the study and 118 ultimately underwent head and neck free flap reconstruction. 57 were randomized to the ICU and 61 to the specialty ward unit. There were no significant differences between the ICU and specialty ward unit groups with regard to demographic variables including age, gender, co-morbidities, tobacco or alcohol use, prior chemotherapy or radiation therapy treatment. There were no significant differences in perioperative variables including need for transfusion, tracheostomy, ischemia time, blood loss, fluid administration or post-operative antibiotic use. There was no significant difference in the primary outcome variable, length of stay. There were no significant differences in the number of the medical or surgical complications, flap failure rate, or hospital costs. CONCLUSION: In this prospective, randomized controlled trial, head and neck free-flap patients cared for on a specialty ward in the immediate post-operative period had equivalent outcomes to those cared for in the ICU.


Assuntos
Retalhos de Tecido Biológico/cirurgia , Neoplasias de Cabeça e Pescoço/cirurgia , Idoso , Feminino , Hospitais , Humanos , Masculino , Período Pós-Operatório , Estudos Prospectivos
4.
Virus Evol ; 4(2): vey021, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30057792

RESUMO

Virus attenuation by genome re-encoding is a pioneering approach for generating effective live-attenuated vaccine candidates. Its core principle is to introduce a large number of synonymous substitutions into the viral genome to produce stable attenuation of the targeted virus. Introduction of large numbers of mutations has also been shown to maintain stability of the attenuated phenotype by lowering the risk of reversion and recombination of re-encoded genomes. Identifying mutations with low fitness cost is pivotal as this increases the number that can be introduced and generates more stable and attenuated viruses. Here, we sought to identify mutations with low deleterious impact on the in vivo replication and virulence of yellow fever virus (YFV). Following comparative bioinformatic analyses of flaviviral genomes, we categorised synonymous transition mutations according to their impact on CpG/UpA composition and secondary RNA structures. We then designed seventeen re-encoded viruses with 100-400 synonymous mutations in the NS2A-to-NS4B coding region of YFV Asibi and Ap7M (hamster-adapted) genomes. Each virus contained a panel of synonymous mutations designed according to the above categorisation criteria. The replication and fitness characteristics of parent and re-encoded viruses were compared in vitro using cell culture competition experiments. In vivo laboratory hamster models were also used to compare relative virulence and immunogenicity characteristics. Most of the re-encoded strains showed no decrease in replicative fitness in vitro. However, they showed reduced virulence and, in some instances, decreased replicative fitness in vivo. Importantly, the most attenuated of the re-encoded strains induced robust, protective immunity in hamsters following challenge with Ap7M, a virulent virus. Overall, the introduction of transitions with no or a marginal increase in the number of CpG/UpA dinucleotides had the mildest impact on YFV replication and virulence in vivo. Thus, this strategy can be incorporated in procedures for the finely tuned creation of substantially re-encoded viral genomes.

5.
Antiviral Res ; 158: 127-134, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30059721

RESUMO

The European Virus Archive (EVA) was created in 2008 with funding from the FP7-EU Infrastructure Programme, in response to the need for a coordinated and readily accessible collection of viruses that could be made available to academia, public health organisations and industry. Within three years, it developed from a consortium of nine European laboratories to encompass associated partners in Africa, Russia, China, Turkey, Germany and Italy. In 2014, the H2020 Research and Innovation Framework Programme (INFRAS projects) provided support for the transformation of the EVA from a European to a global organization (EVAg). The EVAg now operates as a non-profit consortium, with 26 partners and 20 associated partners from 21 EU and non-EU countries. In this paper, we outline the structure, management and goals of the EVAg, to bring to the attention of researchers the wealth of products it can provide and to illustrate how end-users can gain access to these resources. Organisations or individuals who would like to be considered as contributors are invited to contact the EVAg coordinator, Jean-Louis Romette, at jean-louis.romette@univmed.fr.


Assuntos
Arquivos , Bancos de Espécimes Biológicos/organização & administração , Recursos em Saúde/organização & administração , Vírus , Pesquisa Biomédica , Europa (Continente) , Humanos , Disseminação de Informação , Organizações de Serviços Gerenciais , Coronavírus da Síndrome Respiratória do Oriente Médio , Saúde Pública , Controle de Qualidade , Segurança/normas , Virologia/métodos , Febre Amarela/epidemiologia , Febre Amarela/virologia , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/virologia
6.
Vet Parasitol ; 244: 144-153, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28917306

RESUMO

Tritrichomonas foetus (T. foetus) is a flagellated protozoa that infects the distal ileum and proximal colon of domestic cats, as well as the urogenital tract of cattle. Feline trichomonosis is recognized as a prevalent cause of chronic diarrhea in cats worldwide. The suspected route of transmission is fecal-oral, with cats in densely crowded environments at highest risk for infection. Thus, the recommended strategy for minimizing spread of infection is to identify and isolate T. foetus-positive cats from the general population. Rapid identification of infected cats can be challenging due to the inability to accurately and quickly detect the organism in samples at point of care facilities. Thus, identification of targets for use in development of a novel diagnostic test, as well as a vaccine or therapy for T. foetus infection is a significant area of research. Despite a difference in organ tropism between T. foetus genotypes, evidence exists for conserved virulence factors between feline and bovine T. foetus. The bovine T. foetus surface antigen, TF1.17, is an adhesin that is conserved across isolates. Vaccination with the purified antigen results in amelioration of cytopathogenicity and more rapid clearance of infection in cattle. We previously showed that three feline isolates of T. foetus were positive for TF1.17 antigen so we further hypothesized that TF1.17 is conserved across feline T. foetus isolates and that this antigen would represent an attractive target for development of a novel diagnostic test or therapy for feline trichomonosis. In these studies, we used monoclonal antibodies previously generated against 1.15 and 1.17 epitopes of the bovine T. foetus TF1.17 antigen, to evaluate for the presence and role of TF1.17 in the cytopathogenicity of feline T. foetus. A previously validated in vitro co-culture approach was used to model feline T. foetus infection. Immunoblotting, immunofluorescence assays, and flow cytometric analysis confirmed the presence and surface localization of antigen TF1.17 across all feline T. foetus isolates tested. Antigen TF1.17 was notably absent in the presumably nonpathogenic intestinal trichomonad, Pentatrichomonas hominis, a parasite that can be confused microscopically with T. foetus. Similar to bovine trichomoniasis, TF1.17 was found to promote T. foetus adhesion to the intestinal epithelium. These results support further characterization and development of the TF1.17 antigen as a possible target for the diagnosis and prevention of feline T. foetus infection.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos de Protozoários/imunologia , Doenças do Gato/diagnóstico , Infecções Protozoárias em Animais/diagnóstico , Tritrichomonas foetus/imunologia , Vacinação/veterinária , Animais , Antígenos de Superfície/imunologia , Doenças do Gato/parasitologia , Doenças do Gato/prevenção & controle , Gatos , Diarreia/veterinária , Epitopos/imunologia , Genótipo , Mucosa Intestinal/parasitologia , Infecções Protozoárias em Animais/parasitologia , Infecções Protozoárias em Animais/prevenção & controle , Tritrichomonas foetus/genética , Tritrichomonas foetus/isolamento & purificação
7.
J Vet Intern Med ; 31(5): 1414-1419, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28833548

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is a highly prevalent condition in cats. Advanced CKD is associated with hyporexia and vomiting, which typically are attributed to uremic toxins and gastric hyperacidity. However, gastric pH studies have not been performed in cats with CKD. HYPOTHESIS/OBJECTIVES: To determine if cats with CKD have decreased gastric pH compared to age-matched, healthy cats. Based on previous work demonstrating an association of hypergastrinemia and CKD, we hypothesized that cats with CKD would have decreased gastric pH compared to healthy, age-matched control cats. ANIMALS: 10 CKD cats; 9 healthy control cats. METHODS: All cats with concurrent disease were excluded on the basis of history, physical examination, CBC, plasma biochemistry profile, urinalysis, urine culture, serum total thyroxine concentration, and serum symmetric dimethylarginine concentration (controls only) obtained within 24 hours of pH monitoring and assessment of serum gastrin concentrations. Serum for gastrin determination was collected, and 12-hour continuous gastric pH monitoring was performed in all cats. Serum gastrin concentration, mean pH, and percentage time that gastric pH was strongly acidic (pH <1 and <2) were compared between groups. RESULTS: No significant differences in serum gastrin concentrations were observed between groups (medians [range]: CKD, 18.7 ng/dL [<10-659.0]; healthy, 54.6 ng/dL [<10-98.0]; P-value = 0.713) or of any pH parameters including mean ± SD gastric pH (CKD, 1.8 ± 0.5; healthy, 1.6 ± 0.3; P-value = 0.23). CONCLUSIONS AND CLINICAL IMPORTANCE: These findings suggest that cats with CKD may not have gastric hyperacidity compared to healthy cats and, therefore, may not need acid suppression. Thus, further studies to determine if there is a benefit to acid suppression in cats with CKD are warranted.


Assuntos
Doenças do Gato/fisiopatologia , Ácido Gástrico/metabolismo , Gastrinas/sangue , Insuficiência Renal Crônica/veterinária , Animais , Estudos de Casos e Controles , Doenças do Gato/sangue , Gatos , Feminino , Determinação da Acidez Gástrica/veterinária , Concentração de Íons de Hidrogênio , Masculino , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/fisiopatologia
8.
J Vet Intern Med ; 30(3): 779-86, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27062346

RESUMO

BACKGROUND: Chronic proton pump inhibitor administration has been associated with electrolyte and cobalamin deficiency, disrupted bone homeostasis, hypergastrinemia, and rebound acid hypersecretion in humans. It is unknown if this occurs in cats. OBJECTIVES: Prolonged oral omeprazole results in altered bone mineral density or content, serum calcium, magnesium, cobalamin, and gastrin concentrations in healthy cats. ANIMALS: Six healthy adult DSH cats. METHODS: In a within subjects, before and after design, cats received placebo followed by omeprazole (0.83-1.6 mg/kg PO q12h) for 60 days each. Analysis of serum calcium, magnesium, cobalamin, and gastrin concentrations was performed on days 0, 30, and 60. Bone density and content were evaluated on days 0 and 60 of each intervention. Continuous data were analyzed using a two-way ANOVA (α = 0.006). On day 60 of omeprazole administration, continuous intragastric pH monitoring was performed in 2 cats to evaluate the effects of abrupt withdrawal of omeprazole. RESULTS: No significant changes were detected between treatments for any variables, except serum gastrin, which was significantly higher during omeprazole treatment in comparison to placebo (P = 0.002). Evidence of gastric hyperacidity was seen in both cats in which intragastric pH monitoring was performed following cessation of omeprazole. CONCLUSIONS AND CLINICAL IMPORTANCE: Although further studies with larger populations of cats will be needed to draw any definitive conclusions, these preliminary results suggest that prolonged PPI treatment results in hypergastrinemia and abrupt PPI withdrawal might result in RAH in cats.


Assuntos
Densidade Óssea/efeitos dos fármacos , Gatos , Omeprazol/efeitos adversos , Inibidores da Bomba de Prótons/efeitos adversos , Animais , Cálcio/sangue , Estudos Controlados Antes e Depois , Feminino , Determinação da Acidez Gástrica/veterinária , Gastrinas/sangue , Magnésio/sangue , Masculino , Projetos Piloto , Vitamina B 12/sangue
9.
Int J Impot Res ; 27(2): 41-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25056809

RESUMO

The objective of this study was to assess drying time after application of testosterone 2% gel (Fortesta Gel, Endo Pharmaceuticals), time needed for serum total testosterone (TT) to reach the eugonadal range (⩾ 300 ng dl(-1)), and time to steady-state serum TT. Thirty-four men with primary or secondary hypogonadism were enrolled in the study; 31 men were included in the pharmacokinetics (PKs) population. Testosterone 2% gel (40 mg) was applied once daily in the morning to the front and inner thighs for 14 days. Median gel drying time was 2.4 min (95% confidence interval (CI), 1.7-3.4 min; n = 31). Serum TT concentrations reached the target eugonadal range with a median time of 2.9 h (95% CI, 1.9-4.3 h; n = 24). Median time to steady-state serum TT concentration was 1.1 days (95% CI, 0.7-3.4 days; n = 31). Six patients (17.6%; n = 34) reported treatment-related adverse events; all were mild. The results from this 14-day PK study in men with hypogonadism suggest that testosterone 2% gel dries, on average, in <3 min after application and that testosterone 2% gel rapidly reaches the target eugonadal range and attains steady-state serum TT concentrations in about 1 day.


Assuntos
Androgênios/sangue , Androgênios/farmacocinética , Hipogonadismo/tratamento farmacológico , Testosterona/sangue , Testosterona/farmacocinética , Adulto , Idoso , Androgênios/administração & dosagem , Géis , Humanos , Masculino , Pessoa de Meia-Idade , Testosterona/administração & dosagem , Fatores de Tempo
10.
Arch Osteoporos ; 9: 202, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25491658

RESUMO

UNLABELLED: Age-related deterioration of limb bone diaphyseal structure is documented among precontact Inuit foragers from northern Alaska. These findings challenge the concept that bone loss and fracture susceptibility among modern Inuit stem from their transition away from a physically demanding traditional lifestyle toward a more sedentary Western lifestyle. INTRODUCTION: Skeletal fragility is rare among foragers and other traditional-living societies, likely due to their high physical activity levels. Among modern Inuit, however, severe bone loss and fractures are apparently common. This is possibly because of recent Western influences and increasing sedentism. To determine whether compromised bone structure and strength among the Inuit are indeed aberrant for a traditional-living group, data were collected on age-related variation in limb bone diaphyseal structure from a group predating Western influences. METHODS: Skeletons of 184 adults were analyzed from the Point Hope archaeological site. Mid-diaphyseal structure was measured in the humerus, radius, ulna, femur, and tibia using CT. Structural differences were assessed between young, middle-aged, and old individuals. RESULTS: In all bones examined, both females and males exhibited significant age-related reductions in bone quantity. With few exceptions, total bone (periosteal) area did not significantly increase between young and old age in either sex, nor did geometric components of bending rigidity (second moments of area). CONCLUSIONS: While the physically demanding lifestyles of certain traditional-living groups may protect against bone loss and fracture susceptibility, this is not the case among the Inuit. It remains possible, however, that Western characteristics of the modern Inuit lifestyle exacerbate age-related skeletal deterioration.


Assuntos
Ossos do Braço/anatomia & histologia , Fêmur/anatomia & histologia , Inuíte/estatística & dados numéricos , Estilo de Vida , Tíbia/anatomia & histologia , Adolescente , Adulto , Alaska , Doenças Ósseas Metabólicas/etiologia , Diáfises/anatomia & histologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Microb Pathog ; 77: 136-41, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25239874

RESUMO

The discovery and development of methods for isolation, characterisation and taxonomy of viruses represents an important milestone in the study, treatment and control of virus diseases during the 20th century. Indeed, by the late-1950s, it was becoming common belief that most human and veterinary pathogenic viruses had been discovered. However, at that time, knowledge of the impact of improved commercial transportation, urbanisation and deforestation, on disease emergence, was in its infancy. From the late 1960s onwards viruses, such as hepatitis virus (A, B and C) hantavirus, HIV, Marburg virus, Ebola virus and many others began to emerge and it became apparent that the world was changing, at least in terms of virus epidemiology, largely due to the influence of anthropological activities. Subsequently, with the improvement of molecular biotechnologies, for amplification of viral RNA, genome sequencing and proteomic analysis the arsenal of available tools for virus discovery and genetic characterization opened up new and exciting possibilities for virological discovery. Many recently identified but "unclassified" viruses are now being allocated to existing genera or families based on whole genome sequencing, bioinformatic and phylogenetic analysis. New species, genera and families are also being created following the guidelines of the International Committee for the Taxonomy of Viruses. Many of these newly discovered viruses are vectored by arthropods (arboviruses) and possess an RNA genome. This brief review will focus largely on the discovery of new arthropod-borne viruses.


Assuntos
Artrópodes/virologia , Vírus de RNA/classificação , Vírus de RNA/isolamento & purificação , Animais , Virologia/métodos
12.
Clin Microbiol Infect ; 19(8): 699-704, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23594175

RESUMO

West Nile virus (WNV), a mosquito-borne flavivirus in the Japanese encephalitis antigenic group, has caused sporadic outbreaks in humans, horses and birds throughout many of the warmer regions of Europe for at least 20 years. Occasional cases of West Nile encephalitis have also been associated with infected blood transfusions and organ donations. Currently, WNV appears to be expanding its geographical range in Europe and causing increasing numbers of epidemics/outbreaks associated with human morbidity and mortality. This brief review reports on the current epidemic situation regarding WNV in Europe, highlighting the clinical, diagnostic and preventive measures available for controlling this apparently emerging human pathogen.


Assuntos
Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Europa (Continente)/epidemiologia , Humanos , Topografia Médica , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/prevenção & controle
13.
J Comp Pathol ; 149(2-3): 233-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23582972

RESUMO

A 10-year-old, neutered female, crossbred pit bull terrier was presented for cough, haemoptysis and rapidly progressive respiratory difficulty. Thoracic radiographs suggested a soft tissue density at the carina and bronchoscopy revealed a large, broad-based mass obstructing the entire left mainstem bronchus and half of the entrance to the right mainstem bronchus. Microscopically, the mass consisted of neoplastic cells that were packeted into small nests and had strong granular cytoplasmic immunoreactivity to synaptophysin and chromogranin A. Cytoplasmic neurosecretory granules stained strongly by the Grimelius method. A diagnosis of obstructive neuroendocrine tumour was made.


Assuntos
Doenças do Cão/patologia , Neoplasias Pulmonares/veterinária , Tumores Neuroendócrinos/veterinária , Animais , Biomarcadores Tumorais/análise , Cães , Feminino , Imuno-Histoquímica , Neoplasias Pulmonares/patologia , Tumores Neuroendócrinos/patologia
14.
J Virol ; 86(16): 8663-71, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22674986

RESUMO

Tick-borne flaviviruses (TBF) are widely dispersed across Africa, Europe, Asia, Oceania, and North America, and some present a significant threat to human health. Seminal studies on tick-borne encephalitis viruses (TBEV), based on partial envelope gene sequences, predicted a westward clinal pattern of evolution and dispersal across northern Eurasia, terminating in the British Isles. We tested this hypothesis using all available full-length open reading frame (ORF) TBF sequences. Phylogenetic analysis was consistent with current reports. However, linear and nonlinear regression analysis of genetic versus geographic distance combined with BEAST analysis identified two separate clines, suggesting that TBEV spread both east and west from a central point. In addition, BEAST analysis suggested that TBF emerged and dispersed more than 16,000 years ago, significantly earlier than previously predicted. Thus, climatic and ecological changes may have played a greater role in TBF dispersal than humans.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/classificação , Vírus da Encefalite Transmitidos por Carrapatos/genética , Evolução Molecular , Filogeografia , Clima , Análise por Conglomerados , Ecologia , Fases de Leitura Aberta , Análise de Sequência de DNA , Fatores de Tempo
15.
Antiviral Res ; 95(2): 167-71, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22626637

RESUMO

The European Virus Archive (EVA) was conceived as a direct response to the need for a coordinated and readily accessible collection of viruses that could be made available to academia, public health organisations and industry, initially within Europe, but ultimately throughout the world. Although scientists worldwide have accumulated virus collections since the early twentieth century, the quality of the collections and the viruses collected may vary according to the personal interests and agenda of the scientists. Moreover, when laboratories are re-organised or closed, collections are no longer maintained and gradually cease to exist. The tragedy of 9/11 and other disruptive activities have also meant that some previously available biological reagents are no longer openly exchanged between countries. In 2008, funding under the FP7-EU infrastructure programme enabled the initiation of the EVA. Within three years, it has developed from a consortium of nine European laboratories to encompass associated partners in Africa, Russia, China, Turkey, Germany and Italy. There is every reason to believe that EVA will continue to expand and ultimately exist as a globally networked, quality-controlled non-profit archive for the benefit of science. Organizations or individuals who would like to be considered as contributors are invited to contact the EVA coordinator, Jean-Louis Romette, at jean-louis.romette@univmed.fr.


Assuntos
Bancos de Espécimes Biológicos/organização & administração , Pesquisa Biomédica/métodos , Virologia/métodos , Europa (Continente) , Humanos
16.
Vaccine ; 30(13): 2301-8, 2012 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-22306858

RESUMO

Coxsackievirus B3 (CVB3), along with other enteroviruses, is involved in about 50% of myocarditis cases and in the pathogenesis of dilated cardiomyopathy. Prevention of CVB3 infection is therefore highly desirable. Virus-like particles (VLPs) are structurally similar to native virus particles and therefore are far better immunogens than any other subunit vaccines. Recombinant baculoviruses carrying either the intact, entire coding region of CVB3 or the four individual coding regions for virus proteins 1-4 (VP1-4) were constructed. Expression of CVB3 capsid proteins in insect cells infected with recombinant baculovirus was detected by immunofluorescence and Western blot analysis. Sucrose gradient ultracentrifugation fractions of the infected cell lysates contained peaks of CVB3 antigen with an approximate density of 1.14g/ml. Electron microscopy demonstrated the presence of VLP in these sucrose fractions. The CVB3 VLP was non-infectious in tissue culture. SWR (H-2(q)) mice vaccinated with CVB3 VLP developed antibodies to CVB3 capsid proteins after the first boost. Antibody titre was comparable to the level induced by an attenuated CVB3 vaccine. Vaccinated animals were protected from myocarditis when subsequently challenged with cardiovirulent CVB3 (chimera-2). Vaccination with VLP produced from the complete CVB3 coding region gave a greater immune response and afforded better protection than with VLP from the quadruple expression vector. These results demonstrate that CVB3 capsid proteins expressed in insect cells have the intrinsic capacity to assemble into non-infectious VLP, which afforded protection from CVB3 infection to mice when used as a vaccine.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Coxsackievirus/prevenção & controle , Enterovirus Humano B/imunologia , Miocardite/prevenção & controle , Vacinas Virais/imunologia , Vírion/imunologia , Animais , Baculoviridae/genética , Baculoviridae/metabolismo , Proteínas do Capsídeo/imunologia , Proteínas do Capsídeo/metabolismo , Células Cultivadas , Infecções por Coxsackievirus/imunologia , Infecções por Coxsackievirus/virologia , Imunidade Humoral , Masculino , Camundongos , Miocardite/imunologia , Miocardite/virologia , Spodoptera/virologia , Vacinação , Vacinas Virais/administração & dosagem
17.
Mol Ecol ; 21(5): 1042-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22292740

RESUMO

Following the announcement of the first case of rabbit haemorrhagic disease (RHD) in a pet rabbit, housed indoors in Canada for more than 1 year, I submitted an evidence-based explanation to ProMed explaining how RHD might have caused the death of 'one' of the three pet rabbits. I suggested with supporting evidence, that it may have been persistently infected with rabbit haemorrhagic disease virus (RHDV) which may have reactivated to cause the fatal disease. However, in this issue, Peacock et al. have proposed an alternative 'hypothesis' for the appearance of RHD in the pet rabbit. They hypothesise that a non-identified insect or fomite might have become contaminated by a Chinese strain of RHDV somewhere in the US. This insect/fomite then flew or was windborne, from the US to Canada where it entered the house containing three pet rabbits and infected one of them. RHD is non-endemic and is rarely reported in the US, where it has only been observed in domestic European rabbits, held in rabbitries. My proposal was based on the details provided by ProMed, the veterinary report from Canada, where RHDV has never previously been identified and the epidemiological, ecological and evolutionary history of RHDV which includes serological and phylogenetic evidence that ancestral RHDV lineages circulated before 1984. The flying insect hypothesis of Peacock et al. is based on circumstantial evidence and, I believe, has a lower probability of being correct than my evidence-based long-term infection proposal.


Assuntos
Infecções por Caliciviridae/transmissão , Surtos de Doenças , Vírus da Doença Hemorrágica de Coelhos/patogenicidade , Modelos Biológicos , Animais
18.
Nucleic Acids Res ; 39(16): 7034-48, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21622960

RESUMO

We provide experimental evidence of a replication enhancer element (REE) within the capsid gene of tick-borne encephalitis virus (TBEV, genus Flavivirus). Thermodynamic and phylogenetic analyses predicted that the REE folds as a long stable stem-loop (designated SL6), conserved among all tick-borne flaviviruses (TBFV). Homologous sequences and potential base pairing were found in the corresponding regions of mosquito-borne flaviviruses, but not in more genetically distant flaviviruses. To investigate the role of SL6, nucleotide substitutions were introduced which changed a conserved hexanucleotide motif, the conformation of the terminal loop and the base-paired dsRNA stacking. Substitutions were made within a TBEV reverse genetic system and recovered mutants were compared for plaque morphology, single-step replication kinetics and cytopathic effect. The greatest phenotypic changes were observed in mutants with a destabilized stem. Point mutations in the conserved hexanucleotide motif of the terminal loop caused moderate virus attenuation. However, all mutants eventually reached the titre of wild-type virus late post-infection. Thus, although not essential for growth in tissue culture, the SL6 REE acts to up-regulate virus replication. We hypothesize that this modulatory role may be important for TBEV survival in nature, where the virus circulates by non-viraemic transmission between infected and non-infected ticks, during co-feeding on local rodents.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos/genética , Elementos Facilitadores Genéticos , Evolução Molecular , RNA Viral/química , Animais , Sequência de Bases , Células Cultivadas , Vírus da Encefalite Transmitidos por Carrapatos/fisiologia , Flavivirus/genética , Dados de Sequência Molecular , Mutagênese , Conformação de Ácido Nucleico , Fases de Leitura Aberta , Replicação Viral
19.
Epidemiol Infect ; 139(6): 807-17, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21342610

RESUMO

West Nile virus (WNV) is now endemic in the USA. After the widespread surge of virus activity across the USA, research has flourished, and our knowledge base has significantly expanded over the past 10 years since WNV was first recognized in New York City. This article provides a review of the virology of WNV, history, epidemiology, clinical features, pathology of infection, the innate and adaptive immune response, host risk factors for developing severe disease, clinical sequelae following severe disease, chronic infection, and the future of prevention.


Assuntos
Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental , Animais , Culicidae/virologia , Humanos , Imunidade Humoral/imunologia , Fatores de Risco , Estados Unidos/epidemiologia , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/imunologia , Febre do Nilo Ocidental/patologia , Febre do Nilo Ocidental/prevenção & controle , Vacinas contra o Vírus do Nilo Ocidental/uso terapêutico , Vírus do Nilo Ocidental/fisiologia
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