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Impairments of object recognition are core features of neurodegenerative syndromes, in particular posterior cortical atrophy (PCA; the 'visual-variant Alzheimer's disease'). These impairments arise from damage to higher-level cortical visual regions and are often missed or misattributed to common ophthalmological conditions. Consequently, diagnosis can be delayed for years with considerable implications for patients. We report a new test for the rapid measurement of cortical visual loss - the Graded Incomplete Letters Test (GILT). The GILT is an optimised psychophysical variation of a test used to diagnose cortical visual impairment, which measures thresholds for recognising letters under levels of increasing visual degradation (decreasing "completeness") in a similar fashion to ophthalmic tests. The GILT was administered to UK Biobank participants (total n=2,359) and participants with neurodegenerative conditions characterised by initial cortical visual (PCA, n=18) or memory loss (typical Alzheimer's disease, n=9). UK Biobank participants, including both typical adults and those with ophthalmological conditions, were able to recognise letters under low levels of completeness. In contrast, participants with PCA consistently made errors with only modest decreases in completeness. GILT sensitivity to PCA was 83.3% for participants reaching the 80% accuracy cut-off, increasing to 88.9% using alternative cut-offs (60% or 100% accuracy). Specificity values were consistently over 94% when compared to UK Biobank participants without or with documented visual conditions, regardless of accuracy cut-off. These first-release UK Biobank and clinical verification data suggest the GILT has utility in both rapidly detecting visual perceptual losses following posterior cortical damage and differentiating perceptual losses from common eye-related conditions.
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Enfermedad de Alzheimer , Humanos , Femenino , Masculino , Anciano , Reino Unido , Persona de Mediana Edad , Enfermedad de Alzheimer/fisiopatología , Enfermedad de Alzheimer/diagnóstico , Adulto , Trastornos de la Visión/diagnóstico , Trastornos de la Visión/fisiopatología , Bancos de Muestras Biológicas , Anciano de 80 o más Años , Pruebas Neuropsicológicas , Biobanco del Reino UnidoRESUMEN
Experiments were performed on laser wakefield acceleration in the highly nonlinear regime. With laser powers P<250 TW and using an initial spot size larger than the matched spot size for guiding, we were able to accelerate electrons to energies E_{max}>2.5 GeV, in fields exceeding 500 GV m^{-1}, with more than 80 pC of charge at energies E>1 GeV. Three-dimensional particle-in-cell simulations show that using an oversized spot delays injection, avoiding beam loss as the wakefield undergoes length oscillation. This enables injected electrons to remain in the regions of highest accelerating fields and leads to a doubling of energy gain as compared to results from using half the focal length with the same laser.
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A central part of human sulfation pathways is the spatially and temporally controlled desulfation of biologically highly potent steroid hormones. The responsible enzyme - steroid sulfatase (STS) - is highly expressed in placenta and peripheral tissues, such as fat, colon, and the brain. The shape of this enzyme and its mechanism are probably unique in biochemistry. STS was believed to be a transmembrane protein, spanning the Golgi double-membrane by stem region formed by two extended internal alpha-helices. New crystallographic data however challenge this view. STS now is portraited as a trimeric membrane-associated complex. We discuss the impact of these results on STS function and sulfation pathways in general and we hypothesis that this new STS structural understanding suggests product inhibition to be a regulator of STS enzymatic activity.
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Placenta , Esteril-Sulfatasa , Embarazo , Femenino , Humanos , Esteril-Sulfatasa/metabolismo , Placenta/metabolismo , Esteroides , Proteínas de la MembranaRESUMEN
Extraordinary states of highly localised pressure and temperature can be generated upon the collapse of impulsively driven cavities. Direct observation of this phenomenon in solids has proved challenging, but recent advances in high-speed synchrotron radiography now permit the study of highly transient, subsurface events in real time. We present a study on the shock-induced collapse of spherical cavities in a solid polymethyl methacrylate medium, driven to shock states between 0.49 and 16.60 GPa. Utilising multi-MHz phase contrast radiography, extended sequences of the collapse process have been captured, revealing new details of interface motion, material failure and jet instability formation. Results reveal a rich array of collapse characteristics dominated by strength effects at low shock pressures and leading to a hydrodynamic response at the highest loading conditions.
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AIM: We examined the management and outcome of patients suffering complex paediatric lower limb injuries with bone and soft tissue loss. METHOD: Patients were identified from our prospective trauma database (2013-2018). Inclusion criteria were age (<18 years) and open lower-limb trauma. We assessed severity of soft tissue and/or bone loss, fracture complexity, surgical techniques and time to surgery. Paediatric quality of life and psychological trauma impact scores (HRQOL and CRIES), Ganga Hospital Injury Severity score (GHISS), union and complication rates were measured. RESULTS: We identified 32 patients aged between 4 and 17 years. Twenty-nine patients had open tibia fractures including 14 patients with bone loss, one patient had an open femur fracture, one patient an open talus fracture and one an open ankle fracture with dorsal degloving. Thirty injuries were classified intra-operatively as Gustilo IIIB (or equivalent) and two injuries as Gustilo IIIC. In 10 patients primary skin closure was achieved by acute shortening following segmental bone loss. Twenty-two patients required soft tissue coverage: 17 free vascularised flaps, two fascio-cutaneous flaps and three split skin grafts were used. Two patients required vascular repair. Soft tissue coverage was achieved within 72 hours in 26 patients (81%) and within a week in 30 patients (94%). The surgical techniques applied were: circular fine wire frame (19), monolateral external fixator (4) and open reduction internal fixation (8). Median follow up time was 18 (7-65) months. Paediatric quality of life scores were available in 30 patients (91%) with a median total score of 77.2 out of 100. The psychological trauma impact scores showed one in three patients was at risk of developing post-traumatic stress symptoms (PTSD). The GHISS scores ranged from 6-13. All fractures went on to unite over a median time of 3.8 (2-10) months. Three patients (9%) had major complications; two flap failures requiring revision, one femur non-union requiring revision fixation. CONCLUSION: Limb salvage and timely fracture union is possible in children with complex lower limb trauma. Early intervention providing adequate debridement, skeletal stabilisation and early soft-tissue cover including the option of free microvascular reconstruction in small children when required, delivers acceptable outcomes. A multidisciplinary team approach including clinical psychologists to address the psychological impact of trauma provides optimal holistic care for these children and adolescents. Therefore, treatment for these patients should only be performed in paediatric major trauma centres.
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Fracturas de Tobillo/cirugía , Fracturas del Fémur/cirugía , Fijación de Fractura/métodos , Fracturas Abiertas/cirugía , Recuperación del Miembro/métodos , Fracturas de la Tibia/cirugía , Adolescente , Fracturas de Tobillo/diagnóstico por imagen , Niño , Preescolar , Desbridamiento , Fijadores Externos/efectos adversos , Femenino , Fracturas del Fémur/diagnóstico por imagen , Fijación de Fractura/efectos adversos , Fijación Interna de Fracturas/efectos adversos , Fijación Interna de Fracturas/métodos , Curación de Fractura , Fracturas Abiertas/diagnóstico por imagen , Humanos , Extremidad Inferior/lesiones , Masculino , Radiografía , Estudios Retrospectivos , Traumatismos de los Tejidos Blandos/cirugía , Colgajos Quirúrgicos , Infección de la Herida Quirúrgica/etiología , Fracturas de la Tibia/diagnóstico por imagen , Centros Traumatológicos , Resultado del TratamientoRESUMEN
PURPOSE: The purpose of this study was to test fluorine-19 (19F) cellular magnetic resonance (MRI) as a non-invasive imaging modality to track therapeutic cell migration as a surrogate marker of immunotherapeutic effectiveness. MATERIALS AND METHODS: Human peripheral blood mononuclear cell- (PBMC)-derived antigen presenting cell (APC) were labeled with a 19F-perfluorocarbon (PFC) and/or activated with granulocyte macrophage colony-stimulating factor (GM-CSF). Viability, phenotype and cell lineage characterization preceded 19F cellular MRI of PFC+ PBMC under both pre-clinical 9.4 Tesla (T) and clinical 3T conditions in a mouse model. RESULTS: A high proportion of PBMC incorporated PFC without affecting viability, phenotype or cell lineage composition. PFC+ PBMC were in vivo migration-competent to draining and downstream lymph nodes. GM-CSF addition to culture increased PBMC migration to, and persistence within, secondary lymphoid organs. CONCLUSION: 19F cellular MRI is a non-invasive imaging technique capable of detecting and quantifying in vivo cell migration in conjunction with an established APC-based immunotherapy model. 19F cellular MRI can function as a surrogate marker for assessing and improving upon the therapeutic benefit that this immunotherapy provides.
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Factor Estimulante de Colonias de Granulocitos y Macrófagos , Leucocitos Mononucleares , Animales , Flúor , Granulocitos , Humanos , Factor Estimulante de Colonias de Macrófagos , Imagen por Resonancia Magnética , RatonesRESUMEN
PURPOSE: To compare quality of life in children and adolescents with tibial fracture during treatment with either a definitive long-leg cast or Ilizarov frame. METHODS: A prospective, longitudinal cohort study was undertaken. Patients aged between 5 and 17 years with tibial fractures treated definitively using a long-leg cast or Ilizarov frame were recruited at first follow-up. Health related quality of life was measured at each clinic appointment during treatment using the Pediatric Quality of Life Inventory (PedsQL) [1]; a validated measure of age-adjusted physical and psychosocial functioning. Psychological trauma symptoms were assessed using the Children's Revised Impact of Events Scale (CRIES) [2]. Results were analysed based on time from injury (less than 30 days, 30 to 120 days). Data regarding injury and treatment was recorded from the clinical records. Statistical analysis was undertaken using a Kruksal-Wallis test with a Tukey-Kramer subgroup analysis. RESULTS: Twenty-five patients from each group were included in the final analysis. Injuries were more severe in the frame patients based on the AO/OTA classification and number of open fractures. No statistically significant differences were detected in any of the outcome scores between treatment groups at either time point. A significant improvement was found in the child reported physical and total domains in both treatment groups based on time from application (<30 days vs. >30 days, frame: p < 0.0001, cast: pâ¯=â¯0.003). There were no differences in the child reported psychosocial domain scores at any time point or between treatment groups. Parent reported scores only showed a significant physical improvement in the frame group (p < 0.0001). CRIES scores for psychological trauma in the intrusion and avoidance domain improved significantly in the cast group between time points (p < 0.05), Multivariate analysis identified polytrauma, mechanism of injury and time from injury but not treatment modality (cast or frame) as significant predictors of quality of life scores (PedsQL) and severity of post-traumatic symptoms (CRIES). CONCLUSION: We found no difference in health-related quality of life during treatment between our patients treated for tibial fractures using a cast or an Ilizarov frame.
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Fracturas Abiertas , Calidad de Vida , Trastornos por Estrés Postraumático/psicología , Fracturas de la Tibia/cirugía , Adolescente , Niño , Preescolar , Femenino , Curación de Fractura , Humanos , Técnica de Ilizarov , Modelos Lineales , Estudios Longitudinales , Masculino , Análisis Multivariante , Estudios Prospectivos , Escalas de Valoración Psiquiátrica , Recuperación de la Función , Índice de Severidad de la Enfermedad , Férulas (Fijadores) , Trastornos por Estrés Postraumático/etiología , Fracturas de la Tibia/fisiopatología , Fracturas de la Tibia/psicología , Resultado del TratamientoRESUMEN
Mini-sabbaticals are formal short-term training and educational experiences away from an investigator's home research unit. These may include rotations with other research units and externships at government research or regulatory agencies, industry and non-profit programs, and training and/or intensive educational programs. The National Institutes of Health have been encouraging training institutions to consider offering mini-sabbaticals, but given the newness of the concept, limited data are available to guide the implementation of mini-sabbatical programs. In this paper, we review the history of sabbaticals and mini-sabbaticals, report the results of surveys we performed to ascertain the use of mini-sabbaticals at Clinical and Translational Science Award hubs, and consider best practice recommendations for institutions seeking to establish formal mini-sabbatical programs.
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Real-world evidence requires use of new tools and methods to support efficient evidence generation. Among those tools are pragmatic trials, utilization of central/single institutional review board and electronic consent, and data linkages between diverse types of data sources (eg, a trial or registry to administrative claims or electronic medical record data). This article reviews these topics in the context of describing several exemplar use cases specific to rheumatology and provides perspective regarding both the promise and potential pitfalls in using these tools and approaches.
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Almacenamiento y Recuperación de la Información/métodos , Ensayos Clínicos Pragmáticos como Asunto , Enfermedades Reumáticas , Telemedicina , Medicina Basada en la Evidencia/métodos , Medicina Basada en la Evidencia/tendencias , Humanos , Consentimiento Informado , Ensayos Clínicos Pragmáticos como Asunto/instrumentación , Ensayos Clínicos Pragmáticos como Asunto/métodos , Proyectos de Investigación , Enfermedades Reumáticas/epidemiología , Enfermedades Reumáticas/terapiaRESUMEN
BACKGROUND: Preclinical evidence suggests that MEK inhibition promotes accumulation and survival of intratumoral tumor-specific T cells and can synergize with immune checkpoint inhibition. We investigated the safety and clinical activity of combining a MEK inhibitor, cobimetinib, and a programmed cell death 1 ligand 1 (PD-L1) inhibitor, atezolizumab, in patients with solid tumors. PATIENTS AND METHODS: This phase I/Ib study treated PD-L1/PD-1-naive patients with solid tumors in a dose-escalation stage and then in multiple, indication-specific dose-expansion cohorts. In most patients, cobimetinib was dosed once daily orally for 21 days on, 7 days off. Atezolizumab was dosed at 800 mg intravenously every 2 weeks. The primary objectives were safety and tolerability. Secondary end points included objective response rate, progression-free survival, and overall survival. RESULTS: Between 27 December 2013 and 9 May 2016, 152 patients were enrolled. As of 4 September 2017, 150 patients received ≥1 dose of atezolizumab, including 14 in the dose-escalation cohorts and 136 in the dose-expansion cohorts. Patients had metastatic colorectal cancer (mCRC; n = 84), melanoma (n = 22), non-small-cell lung cancer (NSCLC; n = 28), and other solid tumors (n = 16). The most common all-grade treatment-related adverse events (AEs) were diarrhea (67%), rash (48%), and fatigue (40%), similar to those with single-agent cobimetinib and atezolizumab. One (<1%) treatment-related grade 5 AE occurred (sepsis). Forty-five (30%) and 23 patients (15%) had AEs that led to discontinuation of cobimetinib and atezolizumab, respectively. Confirmed responses were observed in 7 of 84 patients (8%) with mCRC (6 responders were microsatellite low/stable, 1 was microsatellite instable), 9 of 22 patients (41%) with melanoma, and 5 of 28 patients (18%) with NSCLC. Clinical activity was independent of KRAS/BRAF status across diseases. CONCLUSIONS: Atezolizumab plus cobimetinib had manageable safety and clinical activity irrespective of KRAS/BRAF status. Although potential synergistic activity was seen in mCRC, this was not confirmed in a subsequent phase III study. CLINICALTRIALS.GOV IDENTIFIER: NCT01988896 (the investigators in the NCT01988896 study are listed in the supplementary Appendix, available at Annals of Oncology online).
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales Humanizados/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Azetidinas/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/metabolismo , Neoplasias/patología , Piperidinas/administración & dosificación , Pronóstico , Tasa de Supervivencia , Distribución Tisular , Adulto JovenRESUMEN
PURPOSE: The purpose of this study was to test a pharmacist-led intervention to improve gout treatment adherence and outcomes. METHODS: We conducted a site-randomized trial (n=1463 patients) comparing a 1-year, pharmacist-led intervention to usual care in patients with gout initiating allopurinol. The intervention was delivered primarily through automated telephone technology. Co-primary outcomes were the proportion of patients adherent (proportion of days covered ≥0.8) and achieving a serum urate <6.0 mg/dl at 1 year. Outcomes were reassessed at year 2. RESULTS: Patients who underwent intervention were more likely than patients of usual care to be adherent (50% vs 37%; odds ratio [OR] 1.68; 95% confidence interval [CI] 1.30, 2.17) and reach serum urate goal (30% vs 15%; OR 2.37; 95% CI 1.83, 3.05). In the second year (1 year after the intervention ended), differences were attenuated, remaining significant for urate goal but not for adherence. The intervention was associated with a 6%-16% lower gout flare rate during year 2, but the differences did not reach statistical significance. CONCLUSIONS: A pharmacist-led intervention incorporating automated telephone technology improved adherence and serum urate goal in patients with gout initiating allopurinol. Although this light-touch, low-tech intervention was efficacious, additional efforts are needed to enhance patient engagement in gout management and ultimately to improve outcomes.
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Alopurinol/uso terapéutico , Supresores de la Gota/uso terapéutico , Gota/tratamiento farmacológico , Cumplimiento de la Medicación/estadística & datos numéricos , Adulto , Anciano , Femenino , Gota/sangre , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Participación del Paciente , Farmacéuticos , Rol Profesional , Teléfono , Resultado del Tratamiento , Ácido Úrico/sangreRESUMEN
Betatron radiation from laser wakefield accelerators is an ultrashort pulsed source of hard, synchrotron-like x-ray radiation. It emanates from a centimetre scale plasma accelerator producing GeV level electron beams. In recent years betatron radiation has been developed as a unique source capable of producing high resolution x-ray images in compact geometries. However, until now, the short pulse nature of this radiation has not been exploited. This report details the first experiment to utilize betatron radiation to image a rapidly evolving phenomenon by using it to radiograph a laser driven shock wave in a silicon target. The spatial resolution of the image is comparable to what has been achieved in similar experiments at conventional synchrotron light sources. The intrinsic temporal resolution of betatron radiation is below 100 fs, indicating that significantly faster processes could be probed in future without compromising spatial resolution. Quantitative measurements of the shock velocity and material density were made from the radiographs recorded during shock compression and were consistent with the established shock response of silicon, as determined with traditional velocimetry approaches. This suggests that future compact betatron imaging beamlines could be useful in the imaging and diagnosis of high-energy-density physics experiments.
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Aims: The aim of this study was to report the clinical, functional and radiological outcomes of children and adolescents with tibial fractures treated using the Ilizarov method. Patients and Methods: Between 2013 and 2016 a total of 74 children with 75 tibial fractures underwent treatment at our major trauma centre using an Ilizarov frame. Demographic and clinical information from a prospective database was supplemented by routine functional and psychological assessment and a retrospective review of the notes and radiographs. Results: Of the 75 fractures, 26 (35%) were open injuries, of which six (8%) had segmental bone loss. There were associated physeal injuries in 18 (24%), and 12 (16%) involved conversion of treatment following failure of previous management. The remaining children had a closed unstable fracture or significant soft-tissue compromise. The median follow-up was 16 months (7 to 31). All fractures united with a median duration in a frame of 3.6 months (interquartile range 3.1 to 4.6); there was no significant difference between the types of fracture and the demographics of the patients. There were no serious complications and no secondary procedures were required to achieve union. Health-related quality of life measures were available for 60 patients (80%) at a minimum of six months after removal of the frame. These indicated a good return to function (median Paediatric quality of life score, 88.0; interquartile range 70.3 to 100). Conclusion: The Ilizarov method is a safe, effective and reliable method for the treatment of complex paediatric tibial fractures. Cite this article: Bone Joint J 2018;100-B:396-403.
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Técnica de Ilizarov , Fracturas de la Tibia/cirugía , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Estudios Prospectivos , Calidad de Vida , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
We report on the experimental studies of laser driven ion acceleration from a double-layer target where a near-critical density target with a few-micron thickness is coated in front of a nanometer-thin diamondlike carbon foil. A significant enhancement of proton maximum energies from 12 to â¼30 MeV is observed when a relativistic laser pulse impinges on the double-layer target under linear polarization. We attributed the enhanced acceleration to superponderomotive electrons that were simultaneously measured in the experiments with energies far beyond the free-electron ponderomotive limit. Our interpretation is supported by two-dimensional simulation results.
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Obstructive airways diseases (OAD) represent a huge burden of illness world-wide, and in spite of the development of effective therapies, significant morbidity and mortality related to asthma and COPD still remains. Over the past decade, our understanding of OAD has improved vastly, and novel treatments have evolved. This evolution is the result of successful translational research, which has connected clinical presentations of OAD and underlying disease mechanisms, thereby enabling the development of targeted treatments. The next challenge of translational research will be to position these novel treatments for OAD for optimal clinical use. At the same time, there is great potential in these treatments providing even better insights into disease mechanisms in OAD by studying the effects of blocking individual immunological pathways. To optimize this potential, there is a need to ensure that translational aspects are added to randomized clinical trials, as well as real-world studies, but also to use other trial designs such as platform studies, which allow for simultaneous assessment of different interventions. Furthermore, demonstrating clinical impact, that is research translation, is an increasingly important component of successful translational research. This review outlines concepts of translational research, exemplifying how translational research has moved management of obstructive airways diseases into the next century, with the introduction of targeted, individualized therapy. Furthermore, the review describes how these therapies may be used as research tools to further our understanding of disease mechanisms in OAD, through translational, mechanistic studies. We underline the current need for implementing basic immunological concepts into clinical care in order to optimize the use of novel targeted treatments and to further the clinical understanding of disease mechanisms. Finally, potential barriers to adoption of novel targeted therapies into routine practice and how these may be overcome are described.
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Enfermedades Pulmonares Obstructivas/terapia , Investigación Biomédica Traslacional/métodos , Investigación Biomédica Traslacional/tendencias , HumanosRESUMEN
Experimental stroke leads to microglia activation and progressive neuronal loss at sites of secondary neurodegeneration (SND). These lesions are remote from, but synaptically connected to, primary infarction sites. Previous studies have demonstrated that immune cells are present in sites of infarction in the first hours and days after stroke, and are associated with increased neurodegeneration in peri-infarct regions. However, it is not known whether immune cells are also present in more distal sites where SND occurs. Our study aimed to investigate whether immune cells are present in sites of SND and, if so, how these cell populations compare to those in the peri-infarct zone. Cells were isolated from the thalamus, the main site of SND, and remaining brain tissue 14days post-stroke. Analysis was performed using flow cytometry to quantify microglia, myeloid cell and lymphocyte numbers. We identified a substantial infiltration of immune cells in the ipsilateral (stroked) compared to the contralateral (control) thalamus, with a significant increase in the percentage of CD4+ and CD8+ T cells. This result was further quantified using immunofluorescent labelling of fixed tissue. In the remaining ipsilateral hemisphere tissue, there were significant increases in the frequency of CD4+ and CD8+ T lymphocytes, B lymphocytes, Ly6G+ neutrophils and both Ly6G-Ly6CLO and Ly6G-Ly6CHI monocytes. Our results indicate that infiltrating immune cells persist in ischemic tissue after the acute ischemic phase, and are increased in sites of SND. Importantly, immune cells have been shown to play pivotal roles in both damage and repair processes after stroke. Our findings indicate that immune cells may also be involved in the pathogenesis of SND and further clinical studies are warranted to characterise the nature of inflammatory cell infiltrates in human disease.
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Isquemia Encefálica/inmunología , Encéfalo/inmunología , Linfocitos/metabolismo , Microglía/inmunología , Células Mieloides/inmunología , Accidente Cerebrovascular/inmunología , Animales , Encéfalo/metabolismo , Encéfalo/patología , Isquemia Encefálica/complicaciones , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Masculino , Ratones Endogámicos C57BL , Microglía/metabolismo , Células Mieloides/metabolismo , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/metabolismo , Accidente Cerebrovascular/patologíaRESUMEN
Nicotinamide nucleotide transhydrogenase, NNT, is a ubiquitous protein of the inner mitochondrial membrane with a key role in mitochondrial redox balance. NNT produces high concentrations of NADPH for detoxification of reactive oxygen species by glutathione and thioredoxin pathways. In humans, NNT dysfunction leads to an adrenal-specific disorder, glucocorticoid deficiency. Certain substrains of C57BL/6 mice contain a spontaneously occurring inactivating Nnt mutation and display glucocorticoid deficiency along with glucose intolerance and reduced insulin secretion. To understand the underlying mechanism(s) behind the glucocorticoid deficiency, we performed comprehensive RNA-seq on adrenals from wild-type (C57BL/6N), mutant (C57BL/6J) and BAC transgenic mice overexpressing Nnt (C57BL/6JBAC). The following results were obtained. Our data suggest that Nnt deletion (or overexpression) reduces adrenal steroidogenic output by decreasing the expression of crucial, mitochondrial antioxidant (Prdx3 and Txnrd2) and steroidogenic (Cyp11a1) enzymes. Pathway analysis also revealed upregulation of heat shock protein machinery and haemoglobins possibly in response to the oxidative stress initiated by NNT ablation. In conclusion, using transcriptomic profiling in adrenals from three mouse models, we showed that disturbances in adrenal redox homeostasis are mediated not only by under expression of NNT but also by its overexpression. Further, we demonstrated that both under expression or overexpression of NNT reduced corticosterone output implying a central role for it in the control of steroidogenesis. This is likely due to a reduction in the expression of a key steroidogenic enzyme, Cyp11a1, which mirrored the reduction in corticosterone output.
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Corteza Suprarrenal/enzimología , Antioxidantes/metabolismo , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/metabolismo , Glucocorticoides/biosíntesis , NADP Transhidrogenasa AB-Específica/metabolismo , Animales , Perfilación de la Expresión Génica , Homeostasis , Masculino , Ratones Endogámicos C57BL , Ratones Transgénicos , Mitocondrias/enzimología , Proteínas Mitocondriales/metabolismo , NADP Transhidrogenasas , Estrés Oxidativo , Peroxiredoxina III/metabolismo , Análisis de Secuencia de ARN , Tiorredoxina Reductasa 2/metabolismoRESUMEN
The morphometric characteristics of the retinal vasculature are associated with future risk of many systemic and vascular diseases. However, analysis of data from large population based studies is needed to help resolve uncertainties in some of these associations. This requires automated systems that extract quantitative measures of vessel morphology from large numbers of retinal images. Associations between retinal vessel morphology and disease precursors/outcomes may be similar or opposing for arterioles and venules. Therefore, the accurate detection of the vessel type is an important element in such automated systems. This paper presents a deep learning approach for the automatic classification of arterioles and venules across the entire retinal image, including vessels located at the optic disc. This comprises of a convolutional neural network whose architecture contains six learned layers: three convolutional and three fully-connected. Complex patterns are automatically learnt from the data, which avoids the use of hand crafted features. The method is developed and evaluated using 835,914 centreline pixels derived from 100 retinal images selected from the 135,867 retinal images obtained at the UK Biobank (large population-based cohort study of middle aged and older adults) baseline examination. This is a challenging dataset in respect to image quality and hence arteriole/venule classification is required to be highly robust. The method achieves a significant increase in accuracy of 8.1% when compared to the baseline method, resulting in an arteriole/venule classification accuracy of 86.97% (per pixel basis) over the entire retinal image.
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Bancos de Muestras Biológicas , Bases de Datos Factuales , Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Disco Óptico , Vasos Retinianos/diagnóstico por imagen , Arteriolas/diagnóstico por imagen , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Disco Óptico/irrigación sanguínea , Disco Óptico/diagnóstico por imagen , Reino Unido , Vénulas/diagnóstico por imagenRESUMEN
Belize, hosting one of the British Army's overseas training areas, provides access to challenging terrain and austere environments, which allows the delivery of training to soldiers on survival and combat within the jungle environment. A 26-year-old infanteer on exercise in Belize presented with progressive bilateral dry, painful, oedematous hands, secondary to the harsh environmental conditions of the jungle and inadequate drying of his hands resulting in his inability to perform his combat duties. The symptoms completely resolved with drying, emollient application and analgesia. While there are no reported cases of immersion hand, comparisons can be made with the well-reported warm weather immersion foot. This case highlights the importance of force preparation and soldier education for units deploying to the jungle. Simple preventive measures, including adequate 'wet-dry' drills and use of emollients can reduce the prevalence of immersion hand, a preventable condition, which can have a significant impact on the overall combat effectiveness of the unit.