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INTRODUCTION: Hoffa fractures are challenging coronally-oriented articular injuries of the femoral condyle. These fractures are rare in adults and extremely rare in the skeletally immature, with few cases reported in literature. To prevent mal- or non-union, Hoffa fractures require prompt surgical stabilisation with anatomic reduction and internal fixation. CASE REPORT: We discuss the case of a lateral distal femoral condyle cartilaginous Hoffa fracture in a ten-year-old male patient. The patient presented after a football non-contact "twist and pop" injury with radiographic imaging described as an osteochondritis dissecans lesion. An MRI was obtained which demonstrated a lateral distal femoral condyle osteochondral fracture. An operative plan was formulated to perform arthroscopic reduction and bio-compression screw fixation to minimize damage to the physis and surrounding tissues. Hyperflexion of the knee allowed for anatomic fracture reduction with the placement of 2 bio-compression screws serving as maintenance of fixation. The patient did well postoperatively and returned to full activity after 6 months. CONCLUSION: Hoffa fractures in the pediatric population are rare and can occur not only through bone but also through the thick chondral layer in younger patients. These are extremely difficult to diagnose through X-Ray alone. The prompt use of MRI imaging allows for operative fixation in a timely fashion, while an arthroscopic-only approach allows for minimal tissue damage. With an appropriate fracture type, hyper-flexion reduces and stabilizes the fracture, permitting the placement of minimally invasive bio-compression fixation.
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Fracturas del Fémur , Fractura de Hoffa , Niño , Humanos , Masculino , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/cirugía , Fémur/lesiones , Fémur/cirugía , Fijación Interna de Fracturas/métodos , RadiografíaRESUMEN
Childhood lead exposure remains a key health concern for officials worldwide, contributing some 600,000 new cases of intellectually disabled children annually. Most children affected by high exposure to lead live in low- and middle-income countries. The leaded gasoline phase out in India was completed in 2000. Yet, in 2020, an estimated 275 million children aged 0 to 9 years had blood lead levels (BLLs) ≥ 5 µg/dL known to adversely affect intelligence and behavior. Lead sources reported in India include spices, cookware, paint, traditional medicines and cosmetics, and lead-acid battery recycling and repair. However, their relative contribution has not been characterized. More than 200 lead pollution sites related to battery recycling and repair activities were identified in Bihar and Jharkhand, India. Ninety percent of the recycling sites had soil lead concentrations exceeding the US Environmental Protection Agency's standards. We compared blood and environmental lead levels in two groups of children in Patna, Bihar. Households in proximity to battery recycling operations (Proximal n = 67) versus households distal to these operations (Distal n = 68). The average age of children was 40 months; 46% were female. Overall, the geometric mean (GM) BLL was 11.6 µg/dL. GM BLLs of children in Proximal and Distal households were not significantly different (10.2 µg/dL vs. 13.1 µg/dL respectively; p≤0.07). About 87% children, 56 Proximal and 62 Distal had BLLs ≥5 µg/dl. Lead concentrations in environmental samples were significantly higher in Proximal households (soil mean 9.8 vs. 1.6 µg/ft2; dust mean 52.9 vs. 29.9 µg/ft2 p<0.001; Proximal vs. Distal respectively) whereas concentrations in all spices were higher in Distal households (mean 46.8 vs 134.5 ppm p<0.001; Proximal vs. Distal respectively), and turmeric (mean 59.4 vs. 216.9 ppm Proximal vs. Distal respectively). In multivariate analyses for all children lead in spices and turmeric and number of rooms in the house were significant while for the Proximal group only lead in spices remained in the model. The predictive value of these models was poor. For the Distal group, a model with lead concentration in spices, turmeric and soil and number of rooms in the house was a much better fit. Of the 34 water samples collected, 7 were above the Indian standard of 10 ppb for lead in drinking water (2 in the Proximal area, 5 in the Distal area). Children in Patna, Bihar, India are exposed to multiple sources of lead, with lead levels in house dust and loose, locally sourced spices the most likely to increase blood lead levels. A holistic approach to blood lead testing and source identification and remediation are necessary to prevent lead exposure.
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Extreme polar vortex events known as sudden stratospheric warmings can influence surface winter weather conditions, but their timing is difficult to predict. Here, we examine factors that influence their occurrence, with a focus on their timing and vertical extent. We consider the roles of the troposphere and equatorial stratosphere separately, using a split vortex event in January 2009 as the primary case study. This event cannot be reproduced by constraining wind and temperatures in the troposphere alone, even when the equatorial lower stratosphere is in the correct phase of the quasi biennial oscillation. When the flow in the equatorial upper stratosphere is also constrained, the timing and spatial evolution of the vortex event is captured remarkably well. This highlights an influence from this region previously unrecognised by the seasonal forecast community. We suggest that better representation of the flow in this region is likely to improve predictability of extreme polar vortex events and hence their associated impacts at the surface.
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Parasitism can result in dramatic changes in host phenotype, which are themselves underpinned by genes and their expression. Understanding how hosts respond at the molecular level to parasites can therefore reveal the molecular architecture of an altered host phenotype. The entomoparasitic nematode Sphaerularia bombi is a parasite of bumblebee (Bombus) hosts where it induces complex behavioural changes and host castration. To examine this interaction at the molecular level, we performed genome-wide transcriptional profiling using RNA-Sequencing (RNA-Seq) of S. bombi-infected Bombus terrestris queens at two critical time-points: during and just after overwintering diapause. We found that infection by S. bombi affects the transcription of genes underlying host biological processes associated with energy usage, translation, and circadian rhythm. We also found that the parasite affects the expression of immune genes, including members of the Toll signalling pathway providing evidence for a novel interaction between the parasite and the host immune response. Taken together, our results identify host biological processes and genes affected by an entomoparasitic nematode providing the first steps towards a molecular understanding of this ecologically important host-parasite interaction.
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Abejas/parasitología , Regulación de la Expresión Génica/inmunología , Interacciones Huésped-Parásitos , Proteínas de Insectos/inmunología , Tylenchida/fisiología , Animales , Abejas/genética , Abejas/inmunología , Diapausa de Insecto , Femenino , Perfilación de la Expresión Génica , Genoma de los Insectos/inmunología , RNA-Seq , Estaciones del AñoRESUMEN
HIV-related stigma and the effect on quality of life is an on-going public health concern despite decades of education, prevention, and intervention efforts. The main purposes of this study were to examine the mediating role of four coping styles and the moderating role of gender on the relationship between HIV-positive status disclosure concerns and eight health-related quality of life outcomes. Data were collected from 346 women and men living with HIV. Results indicated that two coping styles - acquiring social support and positive reframing - mediated the negative relationship between disclosure concerns and health-related quality of life outcomes. There was no support for a moderated mediation. Interventions aimed at helping people living with HIV should focus on identifying and acquiring coping styles that transform perceptions of HIV-related stigma to support disclosure and improve health-related quality of life.
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Adaptación Psicológica , Infecciones por VIH/psicología , Seropositividad para VIH/psicología , Estado de Salud , Calidad de Vida , Estigma Social , Revelación de la Verdad , Adulto , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Factores Sexuales , Apoyo SocialRESUMEN
Microsporidia may cause emerging infectious diseases (EIDs) in bumblebees. Two drivers - commercial bumblebees and managed honey bees - have been identified as possible sources of pathogen spillover. In addition, declines in bumblebee populations may have led to lower genetic diversity and subsequent higher susceptibility to infection, enabling microsporidia to increase in prevalence. There is strong evidence for relatively recent increases in the prevalence of Nosema bombi in North America. However, the lack of definitive data on spillover by microsporidia, in North America or elsewhere, makes it difficult to identify the causes of such increases. Phylogenomic studies are urgently needed to identify the global population structure of microsporidia in bumblebees, and thus identify the source of current and future epidemics.
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Abejas/genética , Abejas/microbiología , Nosema/fisiología , Animales , Variación Genética , América del Norte , Nosema/clasificación , FilogeniaRESUMEN
PURPOSE: We reviewed patients with partial supraclavicular brachial plexus injuries in order to refine the myotome values of the upper limb. METHODS: Forty-two patients with defined partial injuries to the supraclavicular brachial plexus were reviewed from a prospective database. The injuries patterns covered C5, C5-6, C5-7, C5-8, C7-T1 and C8-T1 roots. Upper plexus injuries were classified on the basis of surgical exploration and intraoperative stimulation and lower plexus injuries from MRI. RESULTS: Flexor Carpi Radialis (FCR) was paralyzed in C5-7 injuries, in addition to paralysis of deltoid, supraspinatus, infraspinatus and biceps, when compared to C5-6 injuries. Complete paralysis of Flexor Digitorum Profundus (FDP) and Flexor Digitorum Superficialis (FDS) to all digits was identified in C7-T1 injuries. In C5-8 injuries weakness was noted in FDP of ulnar digits and intrinsics innervated by the ulnar nerve, while in C8-T1 injuries paralysis was noted in the FDP to the radial digits. All patients with C8-T1 injuries had paralysis of FDS and the thenar muscles. CONCLUSIONS: In upper plexus injuries paralysis of FCR indicated involvement of C7 root in addition to C5 and C6 roots. The results provide new detail of innervation of muscles acting on the hand. Flexor muscles and intrinsic muscles of the thumb and radial fingers (median nerve) have an important contribution from T1, while for those acting on the ulnar digits (ulnar nerve) the main contribution is from C8 with some input from C7. T1 also gives consistent innervation to extensor pollicis longus. A revised myotome chart for the upper limb is proposed.
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Plexo Braquial/lesiones , Plexo Braquial/fisiopatología , Fuerza Muscular/fisiología , Adolescente , Adulto , Brazo , Vértebras Cervicales , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vértebras Torácicas , Adulto JovenRESUMEN
Intensification of food production has the potential to drive increased disease prevalence in food plants and animals. Microsporidia are diversely distributed, opportunistic, and density-dependent parasites infecting hosts from almost all known animal taxa. They are frequent in highly managed aquatic and terrestrial hosts, many of which are vulnerable to epizootics, and all of which are crucial for the stability of the animal-human food chain. Mass rearing and changes in global climate may exacerbate disease and more efficient transmission of parasites in stressed or immune-deficient hosts. Further, human microsporidiosis appears to be adventitious and primarily associated with an increasing community of immune-deficient individuals. Taken together, strong evidence exists for an increasing prevalence of microsporidiosis in animals and humans, and for sharing of pathogens across hosts and biomes.
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Enfermedades Transmisibles Emergentes/transmisión , Cadena Alimentaria , Parasitología de Alimentos/tendencias , Microsporidios/fisiología , Microsporidiosis/transmisión , Animales , Enfermedades Transmisibles Emergentes/epidemiología , Enfermedades Transmisibles Emergentes/parasitología , Humanos , Microsporidiosis/epidemiología , Microsporidiosis/parasitologíaRESUMEN
A key component of Russian wheat aphid, Diuraphis noxia (Kurdjumov), management has been through planting resistant wheat cultivars. A new biotype, RWA2, appeared in 2003 which caused widespread damage to wheat cultivars containing the Dn4 gene. Biotypic diversity in Russian wheat aphid populations has not been addressed since 2005 when RWA2 dominated the biotype complex. Our objectives were to determine the biotypic diversity in the Central Great Plains and Colorado Plateau at regional (2010, 2011, 2013) and local (2012) levels and detect the presence of new Russian wheat aphid biotypes. Regional and within-field aphid collections were screened against Russian wheat aphid-resistant wheat genotypes containing genes Dn3, Dn4, Dn6, Dn7, Dn9, CI2401; and resistant barley STARS 9301B. In 2010, all aphid collections from Texas were avirulent to the Dn4 resistance gene in wheat. Regional results revealed Dn4 avirulent RWA6 was widespread (55-84%) in populations infesting wheat in both regions. Biotypes RWA1, 2, and 3/7 were equally represented with percentages<20% each while RWA8 was rarely detected. Combining percentages of RWA1, 6, and 8 across regions to estimate avirulence to Dn4 gene revealed high percentages for both 2011 (64-80%) and 2013 (69-90%). In contrast, the biotype structure at the local level differed where biotype percentages varied up to ≥2-fold between fields. No new biotypes were detected; therefore, Dn7, CI2401, and STARS9301B remained resistant to all known Russian wheat aphid biotypes. This study documents a shift to Dn4 avirulent biotypes and serves as a valuable baseline for biotypic diversity in Russian wheat aphid populations prior to the deployment of new Russian wheat aphid-resistant wheat cultivars.
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Áfidos/fisiología , Triticum/fisiología , Animales , Áfidos/clasificación , Hordeum , Estados UnidosRESUMEN
OBJECTIVE: The amount of clinical information that anesthesia providers encounter creates an environment for information overload and medical error. In an effort to create more efficient OR and PACU EMR viewer platforms, we aimed to better understand the intraoperative and post-anesthesia clinical information needs among anesthesia providers. MATERIALS AND METHODS: A web-based survey to evaluate 75 clinical data items was created and distributed to all anesthesia providers at our institution. Participants were asked to rate the importance of each data item in helping them make routine clinical decisions in the OR and PACU settings. RESULTS: There were 107 survey responses with distribution throughout all clinical roles. 84% of the data items fell within the top 2 proportional quarters in the OR setting compared to only 65% in the PACU. Thirty of the 75 items (40%) received an absolutely necessary rating by more than half of the respondents for the OR setting as opposed to only 19 of the 75 items (25%) in the PACU. Only 1 item was rated by more than 20% of respondents as not needed in the OR compared to 20 data items (27%) in the PACU. CONCLUSION: Anesthesia providers demonstrate a larger need for EMR data to help guide clinical decision making in the OR as compared to the PACU. When creating EMR platforms for these settings it is important to understand and include data items providers deem the most clinically useful. Minimizing the less relevant data items helps prevent information overload and reduces the risk for medical error.
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Periodo de Recuperación de la Anestesia , Actitud del Personal de Salud , Recolección de Datos , Registros Electrónicos de Salud/organización & administración , Evaluación de Necesidades , Sistemas de Información en Quirófanos/organización & administración , Enfermería Posanestésica/organización & administración , Registros de Salud Personal , MinnesotaRESUMEN
Eight biotypes of the Russian wheat aphid, Diuraphis noxia (Kurdjumov), have been discovered in the United States since 2003. Biotypes are identified by the distinct feeding damage responses they produce on wheat carrying different Russian wheat aphid resistance genes, namely, from Dn1 to Dn9. Each Russian wheat aphid biotype has been named using plant damage criteria and virulence categories that have varied between studies. The study was initiated to compare the plant damage caused by all the eight known Russian wheat aphid biotypes, and analyze the results to determine how Russian wheat aphid virulence should be classified. Each Russian wheat aphid biotype was evaluated on 16 resistant or susceptible cereal genotypes. Plant damage criteria included leaf roll, leaf chlorosis, and plant height. The distribution of chlorosis ratings followed a bimodal pattern indicating two categories of plant responses, resistant or susceptible. Correlations were significant between chlorosis ratings and leaf roll (r(2) = 0.72) and between chlorosis ratings and plant height (r(2) = 0.48). The response of 16 cereal genotypes to feeding by eight Russian wheat aphid biotypes found RWA1, RWA2, RWA6, and RWA8 to differ in virulence, while Russian wheat aphid biotypes RWA3, RWA4, RWA5, and RWA7 produced similar virulence profiles. These biotypes have accordingly been consolidated to what is hereafter referred to as RWA3/7. Our results indicated that the five main biotypes RWA1, RWA2, RWA3/7, RWA6, and RWA8 can be identified using only four wheat genotypes containing Dn3, Dn4, Dn6, and Dn9.
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Áfidos/fisiología , Ecotipo , Hordeum/genética , Control de Insectos/métodos , Triticum/genética , Animales , Áfidos/genética , Hordeum/crecimiento & desarrollo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Triticum/crecimiento & desarrolloRESUMEN
Emerging infectious diseases (EIDs) pose a risk to human welfare, both directly and indirectly, by affecting managed livestock and wildlife that provide valuable resources and ecosystem services, such as the pollination of crops. Honeybees (Apis mellifera), the prevailing managed insect crop pollinator, suffer from a range of emerging and exotic high-impact pathogens, and population maintenance requires active management by beekeepers to control them. Wild pollinators such as bumblebees (Bombus spp.) are in global decline, one cause of which may be pathogen spillover from managed pollinators like honeybees or commercial colonies of bumblebees. Here we use a combination of infection experiments and landscape-scale field data to show that honeybee EIDs are indeed widespread infectious agents within the pollinator assemblage. The prevalence of deformed wing virus (DWV) and the exotic parasite Nosema ceranae in honeybees and bumblebees is linked; as honeybees have higher DWV prevalence, and sympatric bumblebees and honeybees are infected by the same DWV strains, Apis is the likely source of at least one major EID in wild pollinators. Lessons learned from vertebrates highlight the need for increased pathogen control in managed bee species to maintain wild pollinators, as declines in native pollinators may be caused by interspecies pathogen transmission originating from managed pollinators.
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Abejas/parasitología , Abejas/virología , Parásitos/patogenicidad , Polinización , Virus ARN/patogenicidad , Animales , Apicultura/métodos , Abejas/clasificación , Abejas/fisiología , Datos de Secuencia Molecular , Parásitos/genética , Parásitos/aislamiento & purificación , Polinización/fisiología , Virus ARN/genética , Virus ARN/aislamiento & purificación , Riesgo , Reino UnidoRESUMEN
STUDY QUESTION: Does first trimester maternal influenza infection increase the risk of non-chromosomal congenital anomalies (CA)? SUMMARY ANSWER: First trimester maternal influenza exposure is associated with raised risk of a number of non-chromosomal CA, including neural tube defects, hydrocephaly, congenital heart defects, cleft lip, digestive system defects and limb reduction defects. WHAT IS KNOWN ALREADY: Hyperthermia is a well-established risk factor for neural tube defects. Previous studies suggest influenza may be a risk factor not only for neural tube defects, but also other CA. No systematic review has previously been undertaken. STUDY DESIGN, SIZE, DURATION: Systematic review and meta-analysis. A search of EMBASE and PUBMED was performed for English and Dutch studies published up to July 2013. A total of 33 studies (15 case-control, 10 cohort and 8 ecological) were included in the systematic review of which 22 studies were included in the meta-analysis. PARTICIPANTS/MATERIALS, SETTINGS, METHODS: A total of 29 542 babies with congenital anomaly (1112 exposed) from case-control studies and 1608 exposed pregnancies resulting in 56 babies with congenital anomaly from cohort studies were included in the meta-analysis. Maternal influenza exposure was defined as any reported influenza, influenza-like illness or fever with flu, with or without serological or clinical confirmation during the first trimester of pregnancy. Data for 24 (sub)groups with congenital anomaly available from ≥3 studies were analysed using the DerSimonian-Laird random effects model. The hypothesis of publication bias was assessed using funnel plots and risk of bias of included studies was assessed using a slightly modified version of the Newcastle-Ottawa scale. MAIN RESULTS AND THE ROLE OF CHANCE: First trimester maternal influenza exposure was associated with an increased risk of any congenital anomaly [adjusted odds ratio (AOR) 2.00, 95% CI: 1.62-2.48], neural tube defects [odds ratio (OR) 3.33, 2.05-5.40], hydrocephaly (5.74, 1.10-30.00), congenital heart defects (1.56, 1.13-2.14), aortic valve atresia/stenosis (AOR 2.59, 1.21-5.54), ventricular septal defect (AOR 1.59, 1.24-2.14), cleft lip (3.12, 2.20-4.42), digestive system (1.72, 1.09-2.68) and limb reduction defects (2.03, 1.27-3.27). An increased risk for cleft lip (but not for cleft palate) was also reported by ecological studies not included in the meta-analysis. Study outcomes reported for 27 subgroups of congenital anomaly could not be included in the meta-analysis. Visual inspection of funnel plots did not suggest evidence for publication bias. LIMITATIONS, REASONS FOR CAUTION: This study enrolled observational studies that can be subject to limitations such as confounding, retrospective maternal exposure reports and non-response of intended participants. Influenza exposed pregnancies can also have been exposed to influenza related medication. WIDER IMPLICATIONS OF THE FINDINGS: Prevention of influenza in pregnant women may reduce congenital anomaly risk, and would be relevant to more than just neural tube defects. More research is needed to determine whether influenza and/or its related medication is teratogenic, to determine the role of hyperthermia in teratogenicity and the role of other environmental factors such as nutritional status in determining susceptibility.
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Anomalías Congénitas/etiología , Fiebre/complicaciones , Gripe Humana/complicaciones , Adulto , Estudios de Cohortes , Femenino , Humanos , Oportunidad Relativa , Embarazo , Primer Trimestre del Embarazo , Factores de RiesgoRESUMEN
The pharmaceutical industry continues to face significant challenges. Very few compounds that enter development reach the marketplace, and the investment required for each success can surpass $1.8 billion. Despite attempts to improve efficiency and increase productivity, total investment continues to rise whereas the output of new medicines declines. With costs increasing exponentially through each development phase, it is failure in phase II and phase III that is most wasteful. In today's development paradigm, late-stage failure is principally a result of insufficient efficacy. This is manifested as either a failure to differentiate sufficiently from placebo (shown for both novel and precedented mechanisms) or a failure to demonstrate sufficient differentiation from existing compounds. Set in this context, this article will discuss the role model-based drug development (MBDD) approaches can and do play in accelerating and optimizing compound development strategies through a series of illustrative examples.
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Descubrimiento de Drogas/métodos , Modelos Biológicos , Ensayos Clínicos como Asunto/economía , Ensayos Clínicos como Asunto/métodos , Simulación por Computador , Descubrimiento de Drogas/economía , Industria Farmacéutica/economía , Industria Farmacéutica/métodos , HumanosRESUMEN
Unknown to its hypertension specialists, a major teaching hospital changed the cuffs on its sphygmomanometers from manufacturer-validated to a uniform washable alternative, in line with 'Health and Safety' concerns surrounding potential cross-contamination between patients. When clinic doctors suspected serious under-reading with the new cuffs, a systematic comparison was undertaken in 54 patients (mean±s.d. age, 61±17 years), using two UM-101 sphygmomanometers, one using the original, manufacturer-supplied cuff and the other with the washable replacement. The study confirmed an average under-reading of 8±10/5±5 mm Hg using the washable cuff, and a third of patients with poorly controlled hypertension were considered normotensive, after using this cuff. The UM-101 sphygmomanometers have now been re-fitted with the original cuffs. Sphygmomanometer cuffs are not interchangeable between devices and a modicum of common sense should be shown to prevent changes made in the name of Health and Safety from having the opposite effect to that intended.
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Determinación de la Presión Sanguínea/instrumentación , Presión Sanguínea , Hipertensión/diagnóstico , Esfigmomanometros , Adulto , Anciano , Determinación de la Presión Sanguínea/efectos adversos , Determinación de la Presión Sanguínea/normas , Errores Diagnósticos , Diseño de Equipo , Femenino , Hospitales de Enseñanza , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Seguridad del Paciente , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Esfigmomanometros/efectos adversos , Esfigmomanometros/normasRESUMEN
The undulate ray Raja undulata is one of the lesser-known skates occurring on the continental shelf of the north-east Atlantic Ocean. It is patchily distributed throughout its range, with sites of local abundance in the central English Channel and off the coasts of Ireland, France, Spain and Portugal. Raja undulata is most abundant in coastal waters (<50 m deep) and is often found in proximity to large estuaries, rias and bays. It is a relatively large-bodied species, attaining a maximum total length (L(T) ) of at least 114 cm, with females maturing at an L(T) of c. 84 cm in Portuguese waters. Although infrequently taken in existing trawl surveys, it can be locally abundant in certain areas, where it can be the dominant skate species. Given its large size, patchy distribution and concern over the possibilities of localized depletions, the IUCN listed R. undulata as an endangered species and, since 2009, the European Union has established regulations to prohibit commercial fisheries landing the species. Given the increased interest in the species, a synopsis of current knowledge is provided, and available data from internationally co-ordinated trawl surveys presented.
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Conservación de los Recursos Naturales , Rajidae/crecimiento & desarrollo , Rajidae/fisiología , Animales , Océano Atlántico , Femenino , Explotaciones Pesqueras , MasculinoRESUMEN
AIM: Production of reactive oxygen species (ROS) in skeletal muscle is markedly increased during exercise and may be essential for exercise adaptation. We, therefore, investigated the effects of infusion with the antioxidant N-acetylcysteine (NAC) on exercise-induced activation of signalling pathways and genes involved in exercise adaptation in human skeletal muscle. METHODS: Subjects completed two exercise tests, 7 days apart, with saline (control, CON) or NAC infusion before and during exercise. Exercise tests comprised of cycling at 71% VO(2peak) for 45 min, and then 92% VO(2peak) to fatigue, with vastus lateralis biopsies at pre-infusion, after 45-min cycling and at fatigue. RESULTS: Analysis was conducted on the mitogen-activated protein kinase signalling pathways, demonstrating that NAC infusion blocked the exercise-induced increase in JNK phosphorylation, but not ERK1/2, or p38 MAPK. Nuclear factor-κB p65 phosphorylation was unaffected by exercise; however, it was reduced in NAC at fatigue by 14% (P < 0.05) compared with pre-infusion. Analysis of exercise and/or ROS-sensitive genes demonstrated that exercise-induced mRNA expression is ROS dependent of MnSOD, but not PGC-1α, interleukin-6, monocyte chemotactic protein-1, or heat-shock protein 70. CONCLUSION: These results suggest that inhibition of ROS attenuates some skeletal muscle cell signalling pathways and gene expression involved in adaptations to exercise.