1,595 research outputs found

    Distribution of melanopsin positive neurons in pigmented and albino mice: evidence for melanopsin interneurons in the mouse retina.

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    Here we have studied the population of intrinsically photosensitive retinal ganglion cells (ipRGCs) in adult pigmented and albino mice. Our data show that although pigmented (C57Bl/6) and albino (Swiss) mice have a similar total number of ipRGCs, their distribution is slightly different: while in pigmented mice ipRGCs are more abundant in the temporal retina, in albinos the ipRGCs are more abundant in superior retina. In both strains, ipRGCs are located in the retinal periphery, in the areas of lower Brn3a(+)RGC density. Both strains also contain displaced ipRGCs (d-ipRGCs) in the inner nuclear layer (INL) that account for 14% of total ipRGCs in pigmented mice and 5% in albinos. Tracing from both superior colliculli shows that 98% (pigmented) and 97% (albino) of the total ipRGCs, become retrogradely labeled, while double immunodetection of melanopsin and Brn3a confirms that few ipRGCs express this transcription factor in mice. Rather surprisingly, application of a retrograde tracer to the optic nerve (ON) labels all ipRGCs, except for a sub-population of the d-ipRGCs (14% in pigmented and 28% in albino, respectively) and melanopsin positive cells residing in the ciliary marginal zone (CMZ) of the retina. In the CMZ, between 20% (pigmented) and 24% (albino) of the melanopsin positive cells are unlabeled by the tracer and we suggest that this may be because they fail to send an axon into the ON. As such, this study provides the first evidence for a population of melanopsin interneurons in the mammalian retina

    Primary immune thrombocytopenia: Experience of a specialised clinic

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    Introduction: Although primary immune thrombocytopenia (ITP) is rare in childhood, it is the most frequent cause of thrombocytopenia. There have been attempts to establish risk factors to predict the progression of the disease in order to optimise its management, which has changed in recent years due to, among other reasons, specialised care. Material and methods: A retrospective, observational and analytical study was conducted on patients diagnosed with ITP over a 3-year period in a Paediatric Haematology specialist clinic. Results: From the epidemiological, clinical and analytical point of view, the characteristics of this group are similar to others. Most of the patients (23/31, 74.2%) had ITP for less than 12 months, with there being no serious complications related to the disease or the treatment received. It was established that risk factors were related to being slowly evolving (lower event free survival (EFS)) with no statistical significance, female gender, age over 10 years, leukopenia absence of initial severe thrombocytopenia, and non-specialised care. The absence of a history of infection was significantly related to a lower EFS. Conclusions: The epidemiological and analytical risk factors for a slowly evolving ITP are the same that described in the literature. Patients treated before the beginning of specialised care also had a lower EFS. These data seem to support the current recommendation that rare diseases should be managed in specialised units. (C) 2019 Published by Elsevier Espana, S.L.U. on behalf of Asociaci6n Espanola de Pediatria. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

    Estudio cinético de la fotodegradación del ión p-hidroxibencenodiazonio en medio polar

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    A study on the photodecomposition of p-hydroxybenzenediazonium ion (PDQ) has been made using chromatographicand spectrophotometric data obtained from UV-irradiated (254 nm) PDQ solutions in acetonitrile and aqueous media.The HPLC and HPLC-mass results indicate that 4-acetamidophenol is the main product formed after the irradiationof PDQ in acetonitrile. This is explained as a consequence of the initial formation of the aryl cation which is laterinvolved in a Ritter’s reaction. A kinetic analysis of the spectrophotometric data reveals that PDQ photodegradation isfaster in acetonitrile (observed rate constant (kobs) = 0.1442 s-1) than in acidifi ed acetonitrile (kobs = 0.009 s-1) indicatinga higher photostability of the protonated species derived from PDQ. The second order constant (0.062 M s-1) found forthe PDQ photodecomposition in phosphate buffer (pH 7) is explained in term of the equilibrium between protonatedand non-protonated species coming from the acid dissociation of PDQSe ha realizado un estudio sobre la fotodescomposiciĂłn del iĂłn p-hidroxibencenodiazonio (PDQ) basado en los datosespectrofotomĂ©tricos y cromatogrĂĄfi cos obtenidos con disoluciones de PDQ expuestas a irradiaciĂłn UV (254 nm) enmedio de acetonitrilo y agua. Los resultados de HPLC y HPLC-masa (HPLC/MS) indican que el 4-acetamidofenoles el principal producto que se forma tras la irradiaciĂłn de PDQ en acetonitrilo. Esto se explica como consecuenciade la formaciĂłn inicial del catiĂłn arilo, que posteriormente participa en una reacciĂłn de Ritter. El anĂĄlisis cinĂ©ticode los datos espectrofotomĂ©tricos revela que la fotodegradaciĂłn de PDQ es mĂĄs rĂĄpida en acetonitrilo (constantede velocidad observada, kobs, = 0,1442 s-1) que en acetonitrilo acidifi cado (kobs = 0,009 s-1), lo que indica una mayorfotoestabilidad de la especie protonada derivada de PDQ. La constante de segundo orden (0,062 M s-1) encontradapara la fotodescomposiciĂłn de PDQ en tampĂłn fosfato (pH 7) se justifi ca por el establecimiento de un equilibrioentre las especies protonada y no protonada procedentes de la disociaciĂłn ĂĄcida de PDQ

    Discoidin domain receptor-1 regulates calcific extracellular vesicle release in vascular smooth muscle cell fibrocalcific response via transforming growth factor-ÎČ signaling

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    Objective - Collagen accumulation and calcification are major determinants of atherosclerotic plaque stability. Extracellular vesicle (EV)-derived microcalcifications in the collagen-poor fibrous cap may promote plaque rupture. In this study, we hypothesize that the collagen receptor discoidin domain receptor-1 (DDR-1) regulates collagen deposition and release of calcifying EVs by vascular smooth muscle cells (SMCs) through the transforming growth factor-ÎČ (TGF-ÎČ) pathway. Approach and Results - SMCs from the carotid arteries of DDR-1-/- mice and wild-type littermates (n=5-10 per group) were cultured in normal or calcifying media. At days 14 and 21, SMCs were harvested and EVs isolated for analysis. Compared with wild-type, DDR-1-/- SMCs exhibited a 4-fold increase in EV release (P<0.001) with concomitantly elevated alkaline phosphatase activity (P<0.0001) as a hallmark of EV calcifying potential. The DDR-1-/- phenotype was characterized by increased mineralization (Alizarin Red S and Osteosense, P<0.001 and P=0.002, respectively) and amorphous collagen deposition (P<0.001). We further identified a novel link between DDR-1 and the TGF-ÎČ pathway previously implicated in both fibrotic and calcific responses. An increase in TGF-ÎČ1 release by DDR-1-/- SMCs in calcifying media (P<0.001) stimulated p38 phosphorylation (P=0.02) and suppressed activation of Smad3. Inhibition of either TGF-ÎČ receptor-I or phospho-p38 reversed the fibrocalcific DDR-1-/- phenotype, corroborating a causal relationship between DDR-1 and TGF-ÎČ in EV-mediated vascular calcification. Conclusions - DDR-1 interacts with the TGF-ÎČ pathway to restrict calcifying EV-mediated mineralization and fibrosis by SMCs. We therefore establish a novel mechanism of cell-matrix homeostasis in atherosclerotic plaque formation

    High genetic diversity at the extreme range edge: nucleotide variation at nuclear loci in Scots pine (Pinus sylvestris L.) in Scotland

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    Nucleotide polymorphism at 12 nuclear loci was studied in Scots pine populations across an environmental gradient in Scotland, to evaluate the impacts of demographic history and selection on genetic diversity. At eight loci, diversity patterns were compared between Scottish and continental European populations. At these loci, a similar level of diversity (Ξsil=~0.01) was found in Scottish vs mainland European populations, contrary to expectations for recent colonization, however, less rapid decay of linkage disequilibrium was observed in the former (ρ=0.0086±0.0009, ρ=0.0245±0.0022, respectively). Scottish populations also showed a deficit of rare nucleotide variants (multi-locus Tajima's D=0.316 vs D=−0.379) and differed significantly from mainland populations in allelic frequency and/or haplotype structure at several loci. Within Scotland, western populations showed slightly reduced nucleotide diversity (πtot=0.0068) compared with those from the south and east (0.0079 and 0.0083, respectively) and about three times higher recombination to diversity ratio (ρ/Ξ=0.71 vs 0.15 and 0.18, respectively). By comparison with results from coalescent simulations, the observed allelic frequency spectrum in the western populations was compatible with a relatively recent bottleneck (0.00175 × 4Ne generations) that reduced the population to about 2% of the present size. However, heterogeneity in the allelic frequency distribution among geographical regions in Scotland suggests that subsequent admixture of populations with different demographic histories may also have played a role

    TĂ©cnicas continuas de depuraciĂłn extrarrenal. ÂżPrecoces o tardĂ­as? ÂżCuĂĄl es el momento idĂłneo para su inicio?

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    The development of acute kidney injury (AKI) is a frequent problem in critical care units (ICUs), specifically in subpopulations admitted with a diagnosis of sepsis or septic shock. In the literature, the indications for the application of CRRT are clear (both of renal and extrarenal origin). However, it seems unclear in any previously published study the ideal time of the beginning of these techniques, nor the impact this has on morbidity and mortality. The objective of this clinical trial is to analyze whether there are differences in mortality between 2 patients groups with AKI and septic shock, depending on the early or late onset of CRRT. It is open (no masking), and may fall into measurement bias during the measurement of the data. The study groups were homogeneous and randomized. However, they do not specify the type of CRRT mode used. The sample size initially calculated according to the power conferred on the study was not finally reached. The measurements were objective. Nonetheless, they do not clarify why they designate the early CRRT as early in the first 12 hours after the development of AKI and late 48 hours later. Results: There are no mortality differences at 90 days (P = 0.38, not significant). It seems that in the late group 38% did not receive CRRT, and 17% received it early. The late group presented significantly fewer days with CRRT. There were no differences in days of mechanical ventilation, vasopressors or ICU stay.El desarrollo de insuficiencia renal aguda (IRA) constituye una problemĂĄtica frecuente en las unidades de cuidados crĂ­ticos (UCI), concretamente en las subpoblaciones ingresadas con diagnĂłstico de sepsis o shock sĂ©ptico. En la literatura, las indicaciones de aplicaciĂłn de TCRR estĂĄn claras (tanto de origen renal como extrarrenal). Sin embargo, no parece claro en ningĂșn estudio publicado previamente el momento ideal del inicio de dichas tĂ©cnicas, ni la repercusiĂłn que esto tiene en la morbimortalidad. El objetivo de este ensayo clĂ­nico es analizar si existen diferencias en la mortalidad entre 2 grupos de pacientes con lesiĂłn renal aguda y shock sĂ©ptico, segĂșn el inicio precoz o tardĂ­o de las TCRR. Es abierto (no hay enmascaramiento), pudiendo caer en sesgo de mediciĂłn durante la mediciĂłn de los datos. Los grupos de estudio fueron homogĂ©neos, con aleatorizaciĂłn al azar. Sin embargo, no especifican el tipo de modalidad de TCRR utilizada. El tamaño muestral calculado inicialmente segĂșn la potencia conferida al estudio no fue alcanzado finalmente. Las mediciones fueron objetivas. Sin embargo, no aclaran por quĂ© designan como precoz al inicio de las TCRR en las primeras 12 horas desde el desarrollo de LRA y tardĂ­o a 48 horas despuĂ©s. Resultados: No hay diferencias de mortalidad a los 90 dĂ­as (P=0.38, no significativo). Sin embargo, en el grupo tardĂ­o un 38% no recibieron TCRR, y 17 % lo recibieron precozmente. El grupo tardĂ­o presentĂł de forma significativa menos dĂ­as con TCRR. No hubo diferencias en dĂ­as de ventilaciĂłn mecĂĄnica, vasopresores ni estancia en UCI

    Patterns of impact resulting from a 'sit less, move more' web-based program in sedentary office employees.

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    PURPOSE: Encouraging office workers to 'sit less and move more' encompasses two public health priorities. However, there is little evidence on the effectiveness of workplace interventions for reducing sitting, even less about the longer term effects of such interventions and still less on dual-focused interventions. This study assessed the short and mid-term impacts of a workplace web-based intervention (Walk@WorkSpain, W@WS; 2010-11) on self-reported sitting time, step counts and physical risk factors (waist circumference, BMI, blood pressure) for chronic disease. METHODS: Employees at six Spanish university campuses (n=264; 42±10 years; 171 female) were randomly assigned by worksite and campus to an Intervention (used W@WS; n=129; 87 female) or a Comparison group (maintained normal behavior; n=135; 84 female). This phased, 19-week program aimed to decrease occupational sitting time through increased incidental movement and short walks. A linear mixed model assessed changes in outcome measures between the baseline, ramping (8 weeks), maintenance (11 weeks) and follow-up (two months) phases for Intervention versus Comparison groups. RESULTS: A significant 2 (group) × 2 (program phases) interaction was found for self-reported occupational sitting (F[3]=7.97, p=0.046), daily step counts (F[3]=15.68, p=0.0013) and waist circumference (F[3]=11.67, p=0.0086). The Intervention group decreased minutes of daily occupational sitting while also increasing step counts from baseline (446±126; 8,862±2,475) through ramping (+425±120; 9,345±2,435), maintenance (+422±123; 9,638±3,131) and follow-up (+414±129; 9,786±3,205). In the Comparison group, compared to baseline (404±106), sitting time remained unchanged through ramping and maintenance, but decreased at follow-up (-388±120), while step counts diminished across all phases. The Intervention group significantly reduced waist circumference by 2.1cms from baseline to follow-up while the Comparison group reduced waist circumference by 1.3cms over the same period. CONCLUSIONS: W@WS is a feasible and effective evidence-based intervention that can be successfully deployed with sedentary employees to elicit sustained changes on "sitting less and moving more"
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