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1.
Opt Express ; 29(19): 30675-30681, 2021 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-34614788

RESUMEN

We present a C-band 6-mode 7-core fiber amplifier in an all-fiberized cladding-pumped configuration for space division multiplexed transmission supporting a record 42 spatial channels. With optimized fiber components (e.g. passively cooled pump laser diode, pump coupler, pump stripper), high power multimode pump light is coupled to the active fiber without any noticeable thermal degradation and an average gain of 18 dB and noise figure of 5.4 dB are obtained with an average differential modal gain of 3.4 dB.

2.
J Fish Biol ; 92(3): 804-827, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29537086

RESUMEN

Populations of fishes provide valuable services for billions of people, but face diverse and interacting threats that jeopardize their sustainability. Human population growth and intensifying resource use for food, water, energy and goods are compromising fish populations through a variety of mechanisms, including overfishing, habitat degradation and declines in water quality. The important challenges raised by these issues have been recognized and have led to considerable advances over past decades in managing and mitigating threats to fishes worldwide. In this review, we identify the major threats faced by fish populations alongside recent advances that are helping to address these issues. There are very significant efforts worldwide directed towards ensuring a sustainable future for the world's fishes and fisheries and those who rely on them. Although considerable challenges remain, by drawing attention to successful mitigation of threats to fish and fisheries we hope to provide the encouragement and direction that will allow these challenges to be overcome in the future.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Explotaciones Pesqueras , Peces/fisiología , Animales , Ecosistema , Peces/crecimiento & desarrollo , Dinámica Poblacional , Calidad del Agua
3.
Annu Rev Virol ; 4(1): 159-180, 2017 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-28715975

RESUMEN

Circular single-stranded DNA viruses infect archaea, bacteria, and eukaryotic organisms. The relatively recent emergence of single-stranded DNA viruses, such as chicken anemia virus (CAV) and porcine circovirus 2 (PCV2), as serious pathogens of eukaryotes is due more to growing awareness than to the appearance of new pathogens or alteration of existing pathogens. In the case of the ubiquitous human circular single-stranded DNA virus family Anelloviridae, there is still no convincing direct causal relation to any specific disease. However, infections may play a role in autoimmunity by changing the homeostatic balance of proinflammatory cytokines and the human immune system, indirectly affecting the severity of diseases caused by other pathogens. Infections with CAV (family Anelloviridae, genus Gyrovirus) and PCV2 (family Circoviridae, genus Circovirus) are presented here because they are immunosuppressive and affect health in domesticated animals. CAV shares genomic organization, genomic orientation, and common features of major proteins with human anelloviruses, and PCV2 DNA may be present in human food and vaccines.


Asunto(s)
Infecciones por Circoviridae/veterinaria , Infecciones por Virus ADN/virología , Virus ADN/genética , ADN Circular , ADN de Cadena Simple/genética , Genoma Viral , Anelloviridae/genética , Anelloviridae/aislamiento & purificación , Animales , Animales Domésticos/virología , Archaea/virología , Autoinmunidad , Bacterias/virología , Virus de la Anemia del Pollo/genética , Virus de la Anemia del Pollo/aislamiento & purificación , Infecciones por Circoviridae/inmunología , Infecciones por Circoviridae/virología , Circovirus/genética , Circovirus/aislamiento & purificación , Infecciones por Virus ADN/inmunología , Virus ADN/aislamiento & purificación , Virus ADN/fisiología , ADN Viral , Humanos , Porcinos/virología , Enfermedades de los Porcinos/virología
4.
Vaccine ; 34(13): 1630-1633, 2016 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-26784685

RESUMEN

Infectious laryngotracheitis (ILT) is a respiratory disease of poultry caused by an alphaherpesvirus, ILTV. The live vaccine is applied worldwide by drinking water or by the respiratory route, and by the vent application in Israel. No system of direct evaluation of the efficacy of vaccination exists today, except of antibody elicitation, which is an indirect indication of vaccination intake and might happen due to environment exposure. We suggest for the first time an assay for evaluating the accuracy of the vaccination process by spotting the spread of the live vaccine systemically, namely by virus detection in the feather shafts of the vaccinated birds. The feathers are particularly beneficial as they are easy to collect, non-lethal for the bird, therefore advantageous for monitoring purposes. Moreover, the continuous survey of the vaccine virus unveiled the different kinetics of viremia by the different vaccination routes; while after the vent vaccination the systemic viremia peaks during the first week afterwards, after two consecutive vaccine administration by drinking water with 6 day interval, the vireamia peaks only after the second administration. A robust amplification was needed because the vaccine ILTV was present in the bird in minute quantities compared to the wild-type virus. For the vaccine virus identification in feather shafts a nested real-time PCR for the TK ILTV gene was developed. The sensitivity of detection of the nested rtPCR was greater by 1000 compared to conventional nested PCR and 10 times that real-time PCR.


Asunto(s)
Plumas/virología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Vacunación/métodos , Vacunación/veterinaria , Vacunas Virales/administración & dosificación , Administración por Inhalación , Administración Oral , Animales , Pollos , ADN Viral/aislamiento & purificación , Infecciones por Herpesviridae/prevención & control , Infecciones por Herpesviridae/veterinaria , Herpesvirus Gallináceo 1 , Enfermedades de las Aves de Corral/prevención & control , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Sensibilidad y Especificidad , Vacunas Atenuadas/administración & dosificación , Viremia/diagnóstico
5.
J Hum Nutr Diet ; 28(4): 384-9, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25664672

RESUMEN

BACKGROUND: Adequate hydration is key to good clinical care and essential for preventing problems in elderly patients such as constipation, pressure sores and confusion. The present study aimed to evaluate fluid provision and consumption in elderly patients against current standards for Scottish hospitals. METHODS: A service evaluation, of fluid provision and consumption over 24 h by elderly orthopaedic rehabilitation patients in a long-stay hospital in Scotland was conducted. Fluids provided and consumed from trolley services, those at meal times and beverages from jugs of water were measured. The average fluid content of a jug, cup and glass on each ward was determined. Each jug of water provided was recorded, as was the acceptance of hot and cold drinks offered. Intake was determined by measuring the leftover water in each jug when these were refreshed and any leftover liquid in patients' cups deducted from that provided. Observations were made with respect to the presentation and encouragement of fluids. RESULTS: Fifty-eight patients (12 males, 46 female, aged ≥65 years) were monitored, of whom 56 were provided with more than the recommended minimum fluid per day [mean (SEM) = 2379 (82) mL]; however, mean intake was lower than recommended [mean (SEM) = 1302 (60) mL; P = 0.002]. Provision of drinks from a trolley service [mean (SEM) = 956 (44) mL] was less than fluid from jugs [mean (SEM) = 1398 (54) mL; P = 0.002]; however, the consumption of drinks from the trolley was greater [77% consumed, mean (SEM) = 770 (46) mL] than from jugs [41% mean (SEM) = 514 (36) mL; P < 0.001]. CONCLUSIONS: Patients consumed significantly more fluid from individual beverages than jugs. Consideration of the method of fluid provision is important with respect to influencing fluid intakes.


Asunto(s)
Bebidas , Ingestión de Líquidos , Rehabilitación , Anciano , Anciano de 80 o más Años , Femenino , Hospitales , Humanos , Masculino , Ingesta Diaria Recomendada , Escocia , Equilibrio Hidroelectrolítico
6.
Oncogene ; 34(25): 3251-63, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25132268

RESUMEN

It is well established that tumours are not homogenous, but comprise cells with differing invasive, proliferative and tumour-initiating potential. A major challenge in cancer research is therefore to develop methods to characterize cell heterogeneity. In melanoma, proliferative and invasive cells are characterized by distinct gene expression profiles and accumulating evidence suggests that cells can alternate between these states through a process called phenotype switching. We have used microfluidic technology to isolate single melanoma cells grown in vitro as monolayers or melanospheres or in vivo as xenografted tumours and analyse the expression profiles of 114 genes that discriminate the proliferative and invasive states by quantitative PCR. Single-cell analysis accurately recapitulates the specific gene expression programmes of melanoma cell lines and defines subpopulations with distinct expression profiles. Cell heterogeneity is augmented when cells are grown as spheres and as xenografted tumours. Correlative analysis identifies gene-regulatory networks and changes in gene expression under different growth conditions. In tumours, subpopulations of cells that express specific invasion and drug resistance markers can be identified amongst which is the pluripotency factor POUF51 (OCT4) whose expression correlates with the tumorigenic potential. We therefore show that single-cell analysis can be used to define and quantify tumour heterogeneity based on detection of cells with specific gene expression profiles.


Asunto(s)
Perfilación de la Expresión Génica , Melanoma/genética , Melanoma/patología , Análisis de la Célula Individual , Animales , Línea Celular Tumoral , Transformación Celular Neoplásica , Humanos , Melanoma/metabolismo , Ratones , Factor de Transcripción Asociado a Microftalmía/metabolismo
7.
Cell Death Differ ; 21(8): 1250-61, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24769727

RESUMEN

Deregulation of signaling pathways that control differentiation, expansion and migration of neural crest-derived melanoblasts during normal development contributes also to melanoma progression and metastasis. Although several epithelial-to-mesenchymal (EMT) transcription factors, such as zinc finger E-box binding protein 1 (ZEB1) and ZEB2, have been implicated in neural crest cell biology, little is known about their role in melanocyte homeostasis and melanoma. Here we show that mice lacking Zeb2 in the melanocyte lineage exhibit a melanoblast migration defect and, unexpectedly, a severe melanocyte differentiation defect. Loss of Zeb2 in the melanocyte lineage results in a downregulation of the Microphthalmia-associated transcription factor (Mitf) and melanocyte differentiation markers concomitant with an upregulation of Zeb1. We identify a transcriptional signaling network in which the EMT transcription factor ZEB2 regulates MITF levels to control melanocyte differentiation. Moreover, our data are also relevant for human melanomagenesis as loss of ZEB2 expression is associated with reduced patient survival.


Asunto(s)
Proteínas de Homeodominio/metabolismo , Factores de Transcripción de Tipo Kruppel/metabolismo , Melanocitos/citología , Melanocitos/metabolismo , Melanoma Experimental/metabolismo , Melanoma Experimental/patología , Factor de Transcripción Asociado a Microftalmía/metabolismo , Proteínas Represoras/metabolismo , Factores de Transcripción/metabolismo , Animales , Diferenciación Celular/fisiología , Progresión de la Enfermedad , Transición Epitelial-Mesenquimal , Proteínas de Homeodominio/genética , Humanos , Factores de Transcripción de Tipo Kruppel/genética , Ratones , Factor de Transcripción Asociado a Microftalmía/genética , Proteínas Represoras/genética , Transducción de Señal , Activación Transcripcional , Caja Homeótica 2 de Unión a E-Box con Dedos de Zinc , Homeobox 1 de Unión a la E-Box con Dedos de Zinc
8.
J Nutr Sci ; 1: e9, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-25191556

RESUMEN

Pomegranate juice (PJ; also known as pomegreat pure juice) provides a rich and varied source of polyphenolic compounds that may offer cardioprotective, anti-atherogenic and antihypertensive effects. The aim of this study was to investigate the effect of PJ consumption on glucocorticoids levels, blood pressure (BP) and insulin resistance in volunteers at high CVD risk. Subjects (twelve males and sixteen females) participated in a randomised, placebo-controlled cross-over study (BMI: 26·77 (sd 3·36) kg/m(2); mean age: 50·4 (sd 6·1) years). Volunteers were assessed at baseline, and at weeks 2 and 4 for anthropometry, BP and pulse wave velocity. Cortisol and cortisone levels in urine and saliva were determined by specific ELISA methods, and the cortisol/cortisone ratio was calculated. Fasting blood samples were obtained to assess plasma lipids, glucose, insulin and insulin resistance (homeostasis model assessment of insulin resistance). Volunteers consumed 500 ml of PJ or 500 ml of a placebo drink containing a similar amount of energy. Cortisol urinary output was reduced but not significant. However, cortisol/cortisone ratios in urine (P = 0·009) and saliva (P = 0·024) were significantly decreased. Systolic BP decreased from 136·4 (sd 6·3) to 128·9 (sd 5·1) mmHg (P = 0·034), and diastolic BP from 80·3 (sd 4·29) to 75·5 (sd 5·17) mmHg (P = 0·031) after 4 weeks of fruit juice consumption. Pulse wave velocity decreased from 7·5 (sd 0·86) to 7·44 (sd 0·94) m/s (P = 0·035). There was also a significant reduction in fasting plasma insulin from 9·36 (sd 5·8) to 7·53 (sd 4·12) mIU/l (P = 0·025) and of homeostasis model assessment of insulin resistance (from 2·216 (sd 1·43) to 1·82 (sd 1·12), P = 0·028). No significant changes were seen in the placebo arm of the study. These results suggest that PJ consumption can alleviate key cardiovascular risk factors in overweight and obese subjects that might be due to a reduction in both systolic and diastolic BP, possibly through the inhibition of 11ß-hydroxysteroid dehydrogenase type 1 enzyme activity as evidenced by the reduction in the cortisol/cortisone ratio. The reduction in insulin resistance might have therapeutic benefits for patients with non-insulin-dependent diabetes, obesity and the metabolic syndrome.

9.
Cell Death Differ ; 19(2): 220-31, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21701496

RESUMEN

The TEAD (1-4) transcription factors comprise the conserved TEA/ATTS DNA-binding domain recognising the MCAT element in the promoters of muscle-specific genes. Despite extensive genetic analysis, the function of TEAD factors in muscle differentiation has proved elusive due to redundancy among the family members. Expression of the TEA/ATTS DNA-binding domain that acts as a dominant negative repressor of TEAD factors in C2C12 myoblasts inhibits their differentiation, whereas selective shRNA knockdown of TEAD4 results in abnormal differentiation characterised by the formation of shortened myotubes. Chromatin immunoprecipitation coupled to array hybridisation shows that TEAD4 occupies 867 promoters including those of myogenic miRNAs. We show that TEAD factors directly induce Myogenin, CDKN1A and Caveolin 3 expression to promote myoblast differentiation. RNA-seq identifies a set of genes whose expression is strongly reduced upon TEAD4 knockdown among which are structural and regulatory proteins and those required for the unfolded protein response. In contrast, TEAD4 represses expression of the growth factor CTGF (connective tissue growth factor) to promote differentiation. Together these results show that TEAD factor activity is essential for normal C2C12 cell differentiation and suggest a role for TEAD4 in regulating expression of the unfolded protein response genes.


Asunto(s)
Diferenciación Celular/genética , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica , Proteínas Musculares/metabolismo , Miogenina/genética , Factores de Transcripción/metabolismo , Respuesta de Proteína Desplegada/genética , Animales , Secuencia de Bases , Fusión Celular , Línea Celular , Inmunoprecipitación de Cromatina , Factor de Crecimiento del Tejido Conjuntivo/genética , Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Técnicas de Silenciamiento del Gen , Ratones , Datos de Secuencia Molecular , Desarrollo de Músculos/genética , Mioblastos/citología , Mioblastos/metabolismo , Miogenina/metabolismo , Regiones Promotoras Genéticas/genética , Unión Proteica/genética , Proteínas Represoras/metabolismo , Factores de Transcripción de Dominio TEA
10.
J Biomech ; 45(3): 614-8, 2012 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-22169153

RESUMEN

Previous studies have used radiostereometric analysis (RSA) to assess the integrity and mechanical properties of repaired tendons and ligament grafts. A conceptually similar approach is to use CT imaging to measure the 3D position and distance between implanted markers. The purpose of this study was to quantify the accuracy and repeatability of measuring the position and distance between metallic markers placed in the rotator cuff using low-dose CT imaging. We also investigated the effect of repeated or variable positions of the arm on position and distance measures. Six human patients had undergone rotator cuff repair and placement of tantalum beads in the rotator cuff at least one year prior to participating in this study. On a single day each patient underwent nine low-dose CT scans in seven unique arm positions. CT scans were analyzed to assess bias, precision and RMS error of the measurement technique. The effect of repeated or variable positions of the arm on the 3D position of the beads and the distance between these beads and suture anchors in the humeral head were also assessed. Results showed the CT imaging method is accurate and repeatable to within 0.7 mm. Further, measures of bead position and anchor-to-bead distance are influenced by arm position and location of the bead within the rotator cuff. Beads located in the posterior rotator cuff moved medially as much as 20 mm in abduction or external rotation. When clinically relevant CT arm positions such as the hand on umbilicus or at side were repeated, bead position varied less than 4 mm in any anatomic direction and anchor-to-bead distance varied +2.8 to -1.6 mm (RMS 1.3 mm). We conclude that a range of ± 3 mm is a conservative estimate of the uncertainty in anchor-to-bead distance for patients repeatedly scanned in clinically-relevant arm positions.


Asunto(s)
Resinas Acrílicas/química , Manguito de los Rotadores/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Humanos , Rango del Movimiento Articular/fisiología , Manguito de los Rotadores/cirugía
11.
Proc Nutr Soc ; 70(4): 426-38, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21854698

RESUMEN

Over a decade of intense research in the field of obesity has led to the knowledge that chronic, excessive adipose tissue expansion leads to an increase in the risk for CVD, type 2 diabetes mellitus and cancer. This is primarily thought to stem from the low-grade, systemic inflammatory response syndrome that characterises adipose tissue in obesity, and this itself is thought to arise from the complex interplay of factors including metabolic endotoxaemia, increased plasma NEFA, hypertrophic adipocytes and localised hypoxia. Plasma concentrations of vitamins and antioxidants are lower in obese individuals than in the non-obese, which is hypothesised to negatively affect the development of inflammation and disease in obesity. This paper provides a review of the current literature investigating the potential of nutraceuticals to ameliorate the development of oxidative stress and inflammation in obesity, thereby limiting the onset of obesity complications. Research has found nutraceuticals able to positively modulate the activity of adipocyte cell lines and further positive effects have been found in other aspects of pathogenic obesity. While their ability to affect weight loss is still controversial, it is clear that they have a great potential to reverse the development of overweight and obesity-related comorbidities; this, however, still requires much research especially that utilising well-structured randomised controlled trials.


Asunto(s)
Adipocitos/patología , Antioxidantes/uso terapéutico , Suplementos Dietéticos , Inflamación/prevención & control , Obesidad/terapia , Humanos , Estado Nutricional , Obesidad/complicaciones , Obesidad/patología , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Pérdida de Peso
12.
Poult Sci ; 90(7): 1462-6, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21673161

RESUMEN

The aim of this study was to determine serological values of lysozyme, hemolytic complement levels (alternative pathway), and bactericidal activity of serum in turkeys kept in different rearing systems (industrial, backyard, and experimental). Results showed that the values for serum bactericidal activity and hemolytic complement levels increased with age, and their values were higher in experimental and in industrial turkeys than in turkeys reared in backyard. Lysozyme concentration showed a similar pattern; its value was higher in the industrial and experimental groups than in the backyard group. Data obtained suggest that rearing system can have an influence on the natural immune parameters considered; experimental and industrial groups showed a similar trend, differentiated from that observed in the backyard group. In the backyard group, the values observed may suggest that hybrid turkeys, selected for high production, have difficulty with being reared outside where predators (foxes and weasels) and weather conditions could be responsible for a stress situation.


Asunto(s)
Crianza de Animales Domésticos/métodos , Proteínas del Sistema Complemento/inmunología , Muramidasa/sangre , Pavos/inmunología , Animales , Femenino , Inmunidad Innata/inmunología , Pavos/sangre
13.
Vet J ; 190(2): e146-e149, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21592830

RESUMEN

Classical swine fever (CSF) re-emerged in Israel in February 2009 after an absence of 62 years. The outbreak occurred on a domestic pig farm in northern Israel and affected domestic pigs and wild boar. On the basis of phylogenetic analysis of a 190 base pair fragment of the E2 glycoprotein gene, the Israeli CSF virus strain belonged to genotype 2.1 and was genetically most similar to a Chinese CSF virus strain.


Asunto(s)
Virus de la Fiebre Porcina Clásica/genética , Peste Porcina Clásica/epidemiología , Brotes de Enfermedades/veterinaria , Animales , Peste Porcina Clásica/virología , ADN Viral/genética , Israel/epidemiología , Epidemiología Molecular , Filogenia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Porcinos
14.
Oncogene ; 30(20): 2319-32, 2011 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-21258399

RESUMEN

Malignant melanoma is an aggressive cancer known for its notorious resistance to most current therapies. The basic helix-loop-helix microphthalmia transcription factor (MITF) is the master regulator determining the identity and properties of the melanocyte lineage, and is regarded as a lineage-specific 'oncogene' that has a critical role in the pathogenesis of melanoma. MITF promotes melanoma cell proliferation, whereas sustained supression of MITF expression leads to senescence. By combining chromatin immunoprecipitation coupled to high throughput sequencing (ChIP-seq) and RNA sequencing analyses, we show that MITF directly regulates a set of genes required for DNA replication, repair and mitosis. Our results reveal how loss of MITF regulates mitotic fidelity, and through defective replication and repair induces DNA damage, ultimately ending in cellular senescence. These findings reveal a lineage-specific control of DNA replication and mitosis by MITF, providing new avenues for therapeutic intervention in melanoma. The identification of MITF-binding sites and gene-regulatory networks establish a framework for understanding oncogenic basic helix-loop-helix factors such as N-myc or TFE3 in other cancers.


Asunto(s)
Reparación del ADN/genética , Replicación del ADN , Regulación Neoplásica de la Expresión Génica , Inestabilidad Genómica , Melanoma/genética , Factor de Transcripción Asociado a Microftalmía/metabolismo , Mitosis/genética , Neoplasias Cutáneas/genética , Sitios de Unión , Línea Celular Tumoral , Linaje de la Célula , Senescencia Celular , Técnicas de Inactivación de Genes , Humanos , Factor de Transcripción Asociado a Microftalmía/genética , Metástasis de la Neoplasia , Neoplasias Cutáneas/metabolismo
15.
Influenza Res Treat ; 2011: 285218, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-23074655

RESUMEN

An avian influenza virus (AIV), A/turkey/Israel/09 subtype H6N1, was isolated from turkey poults exhibiting typical pathology associated with AIV infection. The virus was characterized by RT-PCR using AIV subtype-specific primers and by the haemagglutination inhibition test using AIV subtype-specific antisera. The virus has an intravenous pathogenicity index of 0 and possessed a nucleotide sequence at the cleavage site of the hemagglutinin gene, PQIETR*GLF, associated with avian influenza viruses of low pathogenicity. Unlike the two previous H6N2 isolates originating from domestic ducks and mallard, the A/turkey/Israel/09 (H6N1) was isolated from turkeys. The gene sequences of the A/turkey/Israel/09 (H6N1) virus show divergence from the former Israeli H6 isolates.

16.
Virus Genes ; 41(3): 396-405, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20721688

RESUMEN

The main aims of the present study were to characterize NS1 protein from H9N2 avian influenza viruses (AIVs) isolated in Israel and to investigate the possibility to use NS1-based indirect ELISA. To achieve these purposes, the non-structural gene (NS1) of 79 AIVs of the H9N2 subtype isolated in Israel in 2000-2009 was sequenced and genetically analyzed. The phylogenetic analysis demonstrated that four distinct introductions of H9N2 occurred in Israel during this period. Analysis of the inferred amino acid sequences of the NS1 proteins showed high, about 10%, differences between viruses of the 3rd and 4th introductions. Antibodies against NS1 protein in immune sera were tested by means of indirect ELISA using recombinant NS1 as antigen. Immune sera were obtained from experimentally H9N2-infected chicken after infection on 4, 7, 10, 14, and 21 days. All sera from chickens experimentally infected with 3rd- or 4th-introduction AIV contained anti-NS1 antibodies that were detected by enzyme-linked immunosorbent assay (NS1-ELISA) even though the recombinant NS1 used as antigen for NS1-ELISA differed significantly in its amino acid sequences from the NS1 protein of AIV that caused infection in experimental birds. These findings indicate that the sites of the NS1 protein by which viruses belonging to 3rd and 4th introduction are out of antigenic epitope positions were responsible for the results of NS1-based iELISA.


Asunto(s)
Variación Genética , Subtipo H9N2 del Virus de la Influenza A/genética , Gripe Aviar/virología , Proteínas no Estructurales Virales/genética , Secuencia de Aminoácidos , Animales , Anticuerpos Antivirales/análisis , Anticuerpos Antivirales/inmunología , Secuencia de Bases , Embrión de Pollo , Pollos , Ensayo de Inmunoadsorción Enzimática , Subtipo H9N2 del Virus de la Influenza A/clasificación , Subtipo H9N2 del Virus de la Influenza A/inmunología , Subtipo H9N2 del Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/inmunología , Israel , Datos de Secuencia Molecular , Filogenia , Proteínas no Estructurales Virales/análisis , Proteínas no Estructurales Virales/inmunología
17.
Avian Dis ; 54(1 Suppl): 725-8, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20521722

RESUMEN

The H9N2 avian influenza virus (AIV) subtype has become endemic in Israel since its introduction in 2000. The disease has been economically damaging to the commercial poultry industry, in part because of the synergistic pathology of coinfection with other viral and/or bacterial pathogens. Avian influenza virus viability in the environment depends on the cumulative effects of chemical and physical factors, such as humidity, temperature, pH, salinity, and organic compounds, as well as differences in the virus itself. We sought to analyze the viability of AIV H9N2 strains at three temperatures (37, 20, and 4 C) and at 2 pHs (5.0 and 7.0). Our findings indicated that at 37 C AIV H9N2 isolate 1525 (subgroup IV) survived for a period of time 18 times shorter at 20 C, and 70 times shorter period at 4 C, as measured by a decrease in titer. In addition, the virus was sensitive to a lower pH (pH 5.0) with no detectable virus after 1 wk incubation at 20 C as compared to virus at pH 7.0, which was viable for at least 3 wk at that temperature. The temperature sensitivity of the virus corresponds to the occurrence of H9N2 outbreaks during the winter, and lower pH can greatly affect the viability of the virus.


Asunto(s)
Subtipo H9N2 del Virus de la Influenza A/fisiología , Temperatura , Concentración de Iones de Hidrógeno , Subtipo H9N2 del Virus de la Influenza A/clasificación
18.
J Virol Methods ; 168(1-2): 72-7, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20435070

RESUMEN

Avian influenza viruses (AIVs) of the H9N2 subtype are a major economic problem in the poultry industry in Israel. Most field isolates from the last decade differ significantly from H9N2 isolates from Europe and the USA, rendering published detection methods inadequate. This study aimed to develop a real-time TaqMan((R)) RT-PCR assay, based on a conserved region in the HA9 gene. The assay was validated with viruses representing different genetic subtypes and other common avian pathogens, and was found specific to H9N2. The real-time RT-PCR assay was compared to RT-PCR, which is in routine diagnostic use. Real-time RT-PCR was found to be more sensitive than RT-PCR by 1.5-2.5 orders of magnitude when testing tracheal swabs directly and by 2-3 orders of magnitude allantoic fluid after AIV propagation in embryonated eggs. Sensitivity was quantified by using 10-fold dilutions of the H9-gene amplification fragment, and real-time RT-PCR was found to be 10(4)-fold more sensitive than RT-PCR. Clinical samples, which included tracheal and cloacal swabs, as well as allantoic fluid, were tested by both methods. By real-time RT-PCR 20% more positive H9N2 samples were detected than by RT-PCR. The real-time RT-PCR assay was found suitable for detection and epidemiological survey not only of Israeli H9N2 viruses, but also for isolates from other parts of the world.


Asunto(s)
Subtipo H9N2 del Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/diagnóstico , Gripe Aviar/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Virología/métodos , Alantoides/virología , Animales , Pollos , Cloaca/virología , Hemaglutininas Virales/genética , Israel , Sensibilidad y Especificidad , Tráquea/virología
19.
Antiviral Res ; 86(2): 227-9, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20211651

RESUMEN

BACKGROUND: We investigated the reasons for switching antiretroviral regimens, an issue rarely addressed in cohort studies. METHODS: An observed toxicity switch rate (OTSR) was calculated by Poisson regression using the number of days individuals received each individual antiretroviral drug. RESULTS: Of 3333 individuals receiving HAART, a total of 14% of regimens were switched, the majority occurring after 6 months of therapy. Toxicity was the major reason for switching (61%) and there were no major statistically significant differences in OTSR between the protease inhibitor (OTSR 26.4, 95% CI 18.3-37) and non-nucleoside reverse transcriptase inhibitor (OTSR 22.2, 95% CI 13.6-34.4) based regimes. For individual antiretrovirals, stavudine and zidovudine had significantly higher "switch" scores than all other drugs. CONCLUSIONS: There were no differences between the major HAART classes in OTSR. We suggest that newer antiretrovirals will require differentiation in terms of longer-term toxicity, as this is the major reason for switching.


Asunto(s)
Fármacos Anti-VIH/administración & dosificación , Fármacos Anti-VIH/efectos adversos , Terapia Antirretroviral Altamente Activa/métodos , Infecciones por VIH/tratamiento farmacológico , Estudios de Cohortes , Humanos , Negativa del Paciente al Tratamiento/estadística & datos numéricos
20.
Eur J Neurol ; 17(5): 677-83, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20050884

RESUMEN

BACKGROUND: Eighty percent of people with Guillain-Barré Syndrome (GBS) are said to achieve 'good' outcome. 'Good' outcome has been defined as either of the top two scores (0 = Healthy, 1 = minor symptoms or signs, able to run) on a 7-point ordinal scale called the F-score. This assessment of 'good' outcome appears to be an arbitrary benchmark. This study is the first assessment of the differences in outcome between post-acute GBS sufferers reporting these scores. It attempts to compare the physical and emotional differences between respondents reporting '0' and '1' on the F-Score. METHODS: A postal survey was administered to respondents through the UK Guillain-Barré Syndrome Support Group's national database and included items relating to general patient data, general mobility, F-Score, Hospital Anxiety and Depression Scale, SF 36 and Fatigue Severity Scale. RESULTS: One thousand five hundred and thirty-five members were surveyed, and of 884/1535 (58%) questionnaires were returned. Results indicate significant differences between those scoring '0' on the F-Score and those scoring '1' in the post-acute phase in terms of anxiety, depression, physical functioning, fatigue and wheelchair use on discharge. CONCLUSIONS: Significantly poorer outcomes for those scoring '1' on the F-Score suggest that only those scoring '0' should constitute a 'good' outcome in GBS.


Asunto(s)
Síndrome de Guillain-Barré/epidemiología , Síndrome de Guillain-Barré/terapia , Evaluación de Resultado en la Atención de Salud/métodos , Encuestas y Cuestionarios , Enfermedad Aguda , Anciano , Comorbilidad , Evaluación de la Discapacidad , Femenino , Síndrome de Guillain-Barré/fisiopatología , Encuestas de Atención de la Salud/estadística & datos numéricos , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Recuperación de la Función/fisiología , Resultado del Tratamiento , Reino Unido/epidemiología
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