326 research outputs found
North Pyrenean populations of <em>Megabunus diadema</em> (Fabricius, 1779) (Arachnida: Opiliones) are characterized by highly male-biased sex ratios
<em>Megabunus diadema</em> (Fabricius, 1779) is an Atlantic and European harvestman species characterized by a discontinuous distribution from Scandinavia to the Iberian Peninsula. With very few male individuals ever observed in the field until now, the biological uniqueness of the species lies in its reproduction mode, hitherto regarded as asexual, facultative parthenogenesis.
Based on a large sample of 741 sexed individuals, the study indicates a sex ratio much higher than what was formerly known, equal to 65.58% of males. Locally varying from 0 to 100% (median 75.5% of males), the sex ratio depends indeed on the altitude and the phenological cycle: the proportion of males decreases with increasing altitude and increases gradually during the spring to reach a plateau in summer. By describing populations locally dominated by male individuals and providing new information on the spatial and temporal patterns of tertiary sex ratio, we question the currently admitted reproduction mode of the species which could be normally sexual, at least locally, rather than asexual.
A distribution map of the species on the northern slope of the Pyrenees is provided for the first time. Our study also complements the distribution for the southern slopes of the Pyrenees and the rest of the Iberian Peninsula published recently by Merino-Sáinz et al. (2013).<br><br><em>Megabunus diadema</em> (Fabricius 1779) es una especie de opilión Atlántica y Europea, caracterizada por una distribución discontinua desde Escandinavia a la Península Ibérica. La singularidad biológica de la especie se encuentra en el modo de reproducción, la partenogénesis facultativa, hasta ahora considerada como asexual. De hecho, hasta el momento se han observado muy pocos individuos masculinos en el campo.
Los resultados de este estudio muestran, sobre una amplia muestra (741 individuos sexuados), que la proporción de sexo masculino es muy superior a lo conocido hasta ahora (65%). Localmente este porcentaje puede variar entre 0 y 100% (mediana del 75,5% para los machos). Los resultados muestran que la proporción de sexos depende de la altitud y del ciclo fenológico: la proporción de machos disminuye con la altitud y aumenta gradualmente durante la primavera hasta llegar a una meseta en verano. Para describir las poblaciones dominadas localmente por individuos masculinos y proporcionar nueva información sobre los patrones espaciales y temporales de la proporción de sexos en poblaciones adultas, cuestionamos el modo de reproducción actualmente admitido de la especie que podría ser normalmente sexual, al menos localmente, en lugar de asexual.
Se proporciona, por primera vez, un mapa de distribución de la especie en la vertiente norte de los Pirineos. Nuestro estudio también complementa el estudio publicado recientemente por Merino-Sáinz et al. (2013) sobre su distribución en la vertiente sur de los Pirineos y en el resto de la Península Ibérica
MYB controls erythroid versus megakaryocyte lineage fate decision through the miR-486-3p-mediated downregulation of MAF
The transcription factor MYB has a key role in hematopoietic progenitor cells (HPCs) lineage choice, by enhancing erythropoiesis at the expense of megakaryopoiesis. We previously demonstrated that MYB controls erythroid versus megakaryocyte lineage decision by transactivating KLF1 and LMO2 expression. To further unravel the molecular mechanisms through which MYB affects lineage fate decision, we performed the integrative analysis of miRNA and mRNA changes in MYB-silenced human primary CD34+ HPCs. Among the miRNAs with the highest number of predicted targets, we focused our studies on hsa-miR-486-3p by demonstrating that MYB controls miR-486-3p expression through the transactivation of its host gene, ankyrin-1 (ANK1) and that miR-486-3p affects HPCs commitment. Indeed, overexpression and knockdown experiments demonstrated that miR-486-3p supports the erythropoiesis while restraining the megakaryopoiesis. Of note, miR-486-3p also favors granulocyte differentiation while repressing the macrophage differentiation. To shed some light on the molecular mechanisms through which miR-486-3p affects HPCs lineage commitment, we profiled the gene expression changes upon miR-486-3p overexpression in CD34+ cells. Among the genes downregulated in miR-486-3p-overexpressing HPCs and computationally predicted to be miR-486-3p targets, we identified MAF as a miR-486-3p target by 3′UTR luciferase reporter assay. Noteworthy, MAF overexpression was able to partially reverse the effects of miR-486-3p overexpression on erythroid versus megakaryocyte lineage choice. Moreover, the MYB/MAF co-silencing constrained the skewing of erythroid versus megakaryocyte lineage commitment in MYB-silenced CD34+ cells, by restraining the expansion of megakaryocyte lineage while partially rescuing the impairment of erythropoiesis. Therefore, our data collectively demonstrate that MYB favors erythropoiesis and restrains megakaryopoiesis through the transactivation of miR-486-3p expression and the subsequent downregulation of MAF. As a whole, our study uncovers the MYB/miR-486-3p/MAF axis as a new mechanism underlying the MYB-driven control of erythroid versus megakaryocyte lineage fate decision
LXRs regulate features of age-related macular degeneration and may be a potential therapeutic target
Effective treatments and animal models for the most prevalent neurodegenerative form of blindness in elderly people, called age-related macular degeneration (AMD), are lacking. Genome-wide association studies have identified lipid metabolism and inflammation as AMD-associated pathogenic pathways. Given liver X receptors (LXRs), encoded by the nuclear receptor subfamily 1 group H members 2 and 3 (NR1H3 and NR1H2), are master regulators of these pathways, herein we investigated the role of LXR in human and mouse eyes as a function of age and disease and tested the therapeutic potential of targeting LXR. We identified immunopositive LXR fragments in human extracellular early dry AMD lesions and a decrease in LXR expression within the retinal pigment epithelium (RPE) as a function of age. Aged mice lacking LXR presented with isoform-dependent ocular pathologies. Specifically, loss of the Nr1h3 isoform resulted in pathobiologies aligned with AMD, supported by compromised visual function, accumulation of native and oxidized lipids in the outer retina, and upregulation of ocular inflammatory cytokines, while absence of Nr1h2 was associated with ocular lipoidal degeneration. LXR activation not only ameliorated lipid accumulation and oxidant-induced injury in RPE cells but also decreased ocular inflammatory markers and lipid deposition in a mouse model, thereby providing translational support for pursuing LXR-active pharmaceuticals as potential therapies for dry AMD
Involvement of MAF/SPP1 axis in the development of bone marrow fibrosis in PMF patients
Primary myelofibrosis (PMF) is a myeloproliferative neoplasm characterized by hyperplastic megakaryopoiesis and myelofibrosis. We recently described the upregulation of MAF (v-maf avian musculoaponeurotic fibrosarcoma oncogene homolog) in PMF CD34+ hematopoietic progenitor cells (HPCs) compared to healthy donor. Here we demonstrated that MAF is also upregulated in PMF compared with the essential thrombocytemia (ET) and polycytemia vera (PV) HPCs. MAF overexpression and knockdown experiments shed some light into the role of MAF in PMF pathogenesis, by demonstrating that MAF favors the megakaryocyte and monocyte/macrophage commitment of HPCs and leads to the increased expression of proinflammatory and profibrotic mediators. Among them, we focused our further studies on SPP1 and LGALS3. We assessed SPP1 and LGALS3 protein levels in 115 PMF, 47 ET and 24 PV patients plasma samples and we found that SPP1 plasma levels are significantly higher in PMF compared with ET and PV patients. Furthermore, in vitro assays demonstrated that SPP1 promotes fibroblasts and mesenchymal stromal cells proliferation and collagen production. Strikingly, clinical correlation analyses uncovered that higher SPP1 plasma levels in PMF patients correlate with a more severe fibrosis degree and a shorter overall survival. Collectively our data unveil that MAF overexpression contributes to PMF pathogenesis by driving the deranged production of the profibrotic mediator SPP1
Cultivation of Human Corneal Endothelial Cells Isolated from Paired Donor Corneas
Consistent expansion of human corneal endothelial cells (hCECs) is critical in the development of tissue engineered endothelial constructs. However, a wide range of complex culture media, developed from different basal media have been reported in the propagation of hCECs, some with more success than others. These results are further confounded by donor-to-donor variability. The aim of this study is to evaluate four culture media in the isolation and propagation of hCECs isolated from a series of paired donor corneas in order to negate donor variability
Real-World Apremilast Use for Treatment of Plaque Psoriasis in Italy: Patient Perspective, Characteristics, and Clinical Outcomes from the DARWIN Study
IntroductionWhile several european studies have reported real-world apremilast use, patient-perceived benefits, and treatment satisfaction, local reimbursement criteria for apremilast vary and data from Italy are limited.methodsThe cross-sectional DARWIN study enrolled consecutive patients who had initiated apremilast for plaque psoriasis 6 (+/- 1) months prior to enrolment at a single visit across 24 Italian dermatological sites. disease severity was assessed using body surface area (BSA) and physician global assessment (PGA). patient-reported outcomes assessed 6 (+/- 1) months after apremilast initiation were dermatology life quality Index (DLQI), patient benefit Index (PBI), and 9-item treatment satisfaction questionnaire for medication (TSQM-9).ResultsOf 184 patients enrolled between July 2019 and January 2021, 180 were included in the analysis. at apremilast initiation, median (25th-75th percentile) time since psoriasis diagnosis was 8.6 (3.2-22.2) years; median BSA, 10.0% (5.0-16.0); mean (standard seviation, SD) DLQI total score, 13.5 (8.0). over half (54.9%) of patients with available data reported psoriasis had a very or extremely large effect on their quality of life (QoL); half reported itching (50.6%) and/or special areas involvement (50.0%). most (73.9%) had comorbidities and were biologic-naive (81.5%). the most common reasons for initiating apremilast were lack of efficacy of previous treatment (56.7%) and contraindications to other treatments (44.4%). At 6 (+/- 1) months, most patients were continuing apremilast and/or reported a global PBI score >= 1 (minimum clinical benefit) (86.1% and 90.0%, respectively); approximately half achieved BSA <= 3% and/or DLQI total score <= 5 (47.1% and 48.5%); 18.8% achieved PGA = 0; mean (SD) TSQM-9 global treatment satisfaction score was 59.0 (24.8). apremilast was well tolerated; no new safety signals were identified .conclusions patients treated with apremilast for 6 months in Italian clinical practice reported improved QoL, clinically relevant improvements in symptoms, high treatment satisfaction, and high treatment persistence. our data indicate apremilast is a valuable treatment option for moderate plaque psoriasis. study registration clinical trials.gov identifier, NCT04031027
Intranasal “painless” Human Nerve Growth Factors Slows Amyloid Neurodegeneration and Prevents Memory Deficits in App X PS1 Mice
Nerve Growth Factor (NGF) is being considered as a therapeutic candidate for Alzheimer's disease (AD) treatment but the clinical application is hindered by its potent pro-nociceptive activity. Thus, to reduce systemic exposure that would induce pain, in recent clinical studies NGF was administered through an invasive intracerebral gene-therapy approach. Our group demonstrated the feasibility of a non-invasive intranasal delivery of NGF in a mouse model of neurodegeneration. NGF therapeutic window could be further increased if its nociceptive effects could be avoided altogether. In this study we exploit forms of NGF, mutated at residue R100, inspired by the human genetic disease HSAN V (Hereditary Sensory Autonomic Neuropathy Type V), which would allow increasing the dose of NGF without triggering pain. We show that “painless” hNGF displays full neurotrophic and anti-amyloidogenic activities in neuronal cultures, and a reduced nociceptive activity in vivo. When administered intranasally to APPxPS1 mice ( n = 8), hNGFP61S/R100E prevents the progress of neurodegeneration and of behavioral deficits. These results demonstrate the in vivo neuroprotective and anti-amyloidogenic properties of hNGFR100 mutants and provide a rational basis for the development of “painless” hNGF variants as a new generation of therapeutics for neurodegenerative diseases
Charge induced chemical dynamics in glycine probed with time resolved Auger electron spectroscopy
In the present contribution, we use x rays to monitor charge induced chemical dynamics in the photoionized amino acid glycine with femtosecond time resolution. The outgoing photoelectron leaves behind the cation in a coherent superposition of quantum mechanical eigenstates. Delayed x ray pulses track the induced coherence through resonant x ray absorption that induces Auger decay. Temporal modulation of the Auger electron signal correlated with specific ions is observed, which is governed by the initial electronic coherence and subsequent vibronic coupling to nuclear degrees of freedom. In the time resolved x ray absorption measurement, we monitor the time frequency spectra of the resulting many body quantum wave packets for a period of 175 fs along different reaction coordinates. Our experiment proves that by measuring specific fragments associated with the glycine dication as a function of the pump probe delay, one can selectively probe electronic coherences at early times associated with a few distinguishable components of the broad electronic wave packet created initially by the pump pulse in the cation. The corresponding coherent superpositions formed by subsets of electronic eigenstates and evolving along parallel dynamical pathways show different phases and time periods in the range of amp; 8722;0.3 0.1 amp; 120587; amp; 8804; amp; 120601; amp; 8804; 0.1 0.2 amp; 120587; and 18.2 1.7 amp; 8722;1.4 amp; 8804; amp; 119879; amp; 8804;23.9 1.2 amp; 8722;1.1 fs. Furthermore, for long delays, the data allow us to pinpoint the driving vibrational modes of chemical dynamics mediating charge induced bond cleavage along different reaction coordinate
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