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The extreme astrophysical processes and conditions that characterize the early Universe are expected to result in young galaxies that are dynamically different from those observed today 1 – 5 . This is because the strong effects associated with galaxy mergers and supernova explosions would lead to most young star-forming galaxies being dynamically hot, chaotic and strongly unstable 1 , 2 . Here we report the presence of a dynamically cold, but highly star-forming, rotating disk in a galaxy at redshift 6 z  = 4.2, when the Universe was just 1.4 billion years old. Galaxy SPT–S J041839–4751.9 is strongly gravitationally lensed by a foreground galaxy at z  = 0.263, and it is a typical dusty starburst, with global star-forming 7 and dust properties 8 that are in agreement with current numerical simulations 9 and observations 10 . Interferometric imaging at a spatial resolution of about 60 parsecs reveals a ratio of rotational to random motions of 9.7 ± 0.4, which is at least four times larger than that expected from any galaxy evolution model at this epoch 1 – 5 but similar to the ratios of spiral galaxies in the local Universe 11 . We derive a rotation curve with the typical shape of nearby massive spiral galaxies, which demonstrates that at least some young galaxies are dynamically akin to those observed in the local Universe, and only weakly affected by extreme physical processes. A strongly lensed galaxy at redshift 4.2 appears to be a dynamically cold disk galaxy, similar to spiral galaxies in the local neighbourhood and weakly affected by extreme physical processes.

Understanding how super-massive black holes form and grow in the early Universe has become a major challenge 1 , 2 since it was discovered that luminous quasars existed only 700 million years after the Big Bang 3 , 4 . Simulations indicate an evolutionary sequence of dust-reddened quasars emerging from heavily dust-obscured starbursts that then transition to unobscured luminous quasars by expelling gas and dust 5 . Although the last phase has been identified out to a redshift of 7.6 (ref. 6 ), a transitioning quasar has not been found at similar redshifts owing to their faintness at optical and near-infrared wavelengths. Here we report observations of an ultraviolet compact object, GNz7q, associated with a dust-enshrouded starburst at a redshift of 7.1899 ± 0.0005. The host galaxy is more luminous in dust emission than any other known object at this epoch, forming 1,600 solar masses of stars per year within a central radius of 480 parsec. A red point source in the far-ultraviolet is identified in deep, high-resolution imaging and slitless spectroscopy. GNz7q is extremely faint in X-rays, which indicates the emergence of a uniquely ultraviolet compact star-forming region or a Compton-thick super-Eddington black-hole accretion disk at the dusty starburst core. In the latter case, the observed properties are consistent with predictions from cosmological simulations 7 and suggest that GNz7q is an antecedent to unobscured luminous quasars at later epochs. An unusual ultraviolet compact object associated with a dusty starburst has been observed at a redshift of about 7.2, with a luminosity that falls between that of quasars and galaxies, possibly in transition between the two. 

Neurofibromatosis type 1 (NF1) is a rare autosomal dominant disorder characterized by proliferation of cells from neural crest origin. The most common manifestations are cutaneous, neurologic, skeletal and ocular. The distinction of NF1 from other syndromes with multiple café-au-lait macules may be difficult in the pediatric age group, and ocular findings, especially Lisch nodules (i.e., melanocytic hamartomas on the irides), are a useful, early diagnostic tool. In recent years, novel ocular manifestations descriptively referred to as “choroidal abnormalities”, choroidal “hyperpigmented spots” and “retinal vascular abnormalities” have been recognized in NF1. Choroidal abnormalities (CA) appear as bright patchy nodules that can be best detected with near-infrared ocular coherence tomography imaging (NIR-OCT). Because of their high specificity and sensitivity for NF1, CA have been added as an ocular diagnostic criterion of NF1 as an alternative to Lisch nodules. Although CA are important ocular diagnostic criteria for NF1, the histologic correlates are controversial. We present the postmortem ocular pathology findings of an NF1 patient for whom clinical notes and ocular imaging were available. Findings in this patient included choroidal hyperpigmented spots on funduscopy and retinal vascular abnormalities, both of which have been reported to be closely associated with CA. Histologic examination of the eyes showed multiple clusters of melanocytes of varying sizes in the choroid. Pathologic review of 12 additional postmortem eyes from 6 NF1 patients showed multiple, bilateral choroidal melanocytic aggregates in all eyes. These findings suggest that the CA seen on NIR-OCT and the hyperpigmented spots seen clinically in NF1 patients are manifestations of multifocal choroidal melanocytic clusters, consistent with choroidal melanocytic hamartomas. Lisch nodules, often multiple, were present in all eyes with morphology that differed from the choroidal hamartomas. As such, although CA and Lisch nodules are melanocytic hamartomas, there are clear phenotypical differences in their morphologies.

Non-arteritic anterior ischemic optic neuropathy (NAION) is the most common cause of non-glaucomatous optic neuropathy in older adults. Optical coherence tomographic angiography (OCT-A) is an emerging, non-invasive method to study the microvasculature of the posterior pole, including the optic nerve head. The goal of this study was to assess the vascular changes in the optic nerve head and peripapillary area associated with NAION using OCT-A. Retrospective comparative case series. We performed OCT-A in 25 eyes (7 acute and 18 non-acute) in 19 patients with NAION. Fellow, unaffected eyes were analyzed for comparison. Patent macro- and microvascular densities were quantified in the papillary and peripapillary regions of unaffected, acutely affected, and non-acutely affected eyes and compared across these groups according to laminar segment and capillary sampling region, and with respect to performance on automated visual field testing. In acutely affected eyes, OCT-A revealed a reduction in the signal from the major retinal vessels and dilation of patent superficial capillaries in the peripapillary area. By contrast, non-acutely affected eyes showed attenuation of patent capillaries. The peripapillary choriocapillaris was obscured by edema in acute cases, but was similar between non-acute and unaffected eyes. The degree of dilation of the superficial microvasculature in the acute phase and attenuation in the non-acute phase each correlated inversely with visual field performance. The region of reduced patent capillary density correlated with the location of visual field defects in 80% of acute cases and 80% of non-acute cases. OCT-A reveals a dynamic shift in the superficial capillary network of the optic nerve head with strong functional correlates in both the acute and non-acute phases of NAION. Further study may validate OCT-A as a useful adjunctive diagnostic tool in the evaluation of ischemic optic neuropathy.

The phase transition between galaxies and quasars is often identified with the rare population of hyper-luminous, hot dust-obscured galaxies. Galaxy formation models predict these systems to grow via mergers, that can deliver large amounts of gas toward their centers, induce intense bursts of star formation and feed their supermassive black holes. Here we report the detection of 24 galaxies emitting Lyman- α emission on projected physical scales of about 400 kpc around the hyper-luminous hot dust-obscured galaxy W0410-0913, at redshift z  = 3.631, using Very Large Telescope observations. While this indicates that W0410-0913 evolves in a very dense environment, we do not find clear signs of mergers that could sustain its growth. Data suggest that if mergers occurred, as models expect, these would involve less massive satellites, with only a moderate impact on the internal interstellar medium of W0410-0913, which is sustained by a rotationally-supported fast-rotating molecular disk, as Atacama Large Millimeter Array observations suggest. Lyman-alpha emission is one of the observational probes for the high-redshift universe. Here, the authors show several Lyman-alpha emitting companion galaxies around the hot dust-obscured galaxy W0410-091 suggesting that the galaxy evolves in a very dense environment.

This case describes a 12-year-old patient with a known history of an actin-alpha 2 (ACTA2) gene mutation who presented with an ophthalmic artery occlusion (OAO). The patient's medical history was significant for multiple strokes and a left homonymous hemianopia. She presented to the emergency department with acute visual loss in the right eye and hypertension and was diagnosed with an OAO affecting the right eye. The aim of this report is to highlight a unique ophthalmic complication associated with ACTA2 mutations not previously documented in the literature.

Widespread genome hypo-methylation and promoter hyper-methylation of epithelium-specific genes are hallmarks of stable epithelial-to-mesenchymal transition (EMT), which in prostate cancer (PCa) correlates with castration resistance, cancer stem cells generation, chemoresistance and worst prognosis. Exploiting our consolidated ‘ ex-vivo ’ system, we show that cancer-associated fibroblasts (CAFs) released factors have pivotal roles in inducing genome methylation changes required for EMT and stemness in EMT-prone PCa cells. By global DNA methylation analysis and RNA-Seq, we provide compelling evidence that conditioned media from CAFs explanted from two unrelated patients with advanced PCa, stimulates concurrent DNA hypo- and hyper-methylation required for EMT and stemness in PC3 and DU145, but not in LN-CaP and its derivative C4-2B, PCa cells. CpG island (CGI) hyper-methylation associates with repression of genes required for epithelial maintenance and invasion antagonism, whereas activation of EMT markers and stemness genes correlate with CGI hypo-methylation. Remarkably, methylation variations and EMT-regulated transcripts almost completely reverse qualitatively and quantitatively during MET. Unsupervised clustering analysis of the PRAD TCGA data set with the differentially expressed (DE) and methylated EMT signature, identified a gene cluster of DE genes defined by a CAF+ and AR- phenotype and worst diagnosis. This gene cluster includes the relevant factors for EMT and stemness, which display DNA methylation variations in regulatory regions inversely correlated to their expression changes, thus strongly sustaining the ex-vivo data. DNMT3A-dependent methylation is essential for silencing epithelial maintenance and EMT counteracting genes, such as CDH1 and GRHL2 , that is, the direct repressor of ZEB1 , the key transcriptional factor for EMT and stemness. Accordingly, DNMT3A knock-down prevents EMT entry. These results shed light on the mechanisms of establishment and maintenance of coexisting DNA hypo- and hyper-methylation patterns during cancer progression, the generation of EMT and cell stemness in advanced PCa, and may pave the way to new therapeutic implications.

The N-palmitoylethanolamine (PEA) is an endogenous member of the endocannabinoid system (ECS) with several biological functions, including a neuromodulatory activity in the central nervous system. To shed light on the neuronal function of PEA, we investigated its involvement in the control of both excitatory and inhibitory transmission in the murine striatum, a brain region strongly modulated by the ECS. By means of electrophysiological recordings, we showed that PEA modulates inhibitory synaptic transmission, through activation of GPR55 receptors, promoting a transient increase of GABAergic spontaneous inhibitory postsynaptic current (sIPSC) frequency. The subsequently rundown effect on sIPSC frequency was secondary to the delayed stimulation of presynaptic cannabinoid CB1 receptors (CB1Rs) by the endocannabinoid 2-AG, whose synthesis was stimulated by PEA on postsynaptic neurons. Our results indicate that PEA, acting on GPR55, enhances GABA transmission in the striatum, and triggers a parallel synthesis of 2-AG at the postsynaptic site, that in turn acts in a retrograde manner to inhibit GABA release through the stimulation of presynaptic CB1Rs. This electrophysiological study identifies a previously unrecognized function of PEA and of GPR55, demonstrating that GABAergic transmission is under the control of this compound and revealing that PEA modulates the release of the endocannabinoid 2-AG.

Purpose While SARS-CoV-2 infection appears not to be clinically evident in the testes, indirect inflammatory effects and fever may impair testicular function. To date, few long-term data of semen parameters impairment after recovery and comprehensive andrological evaluation of recovered patients has been published. The purpose of this study was to investigate whether SARS-CoV-2 infection affect male reproductive health. Methods Eighty patients were recruited three months after COVID-19 recovery. They performed physical examination, testicular ultrasound, semen analysis, sperm DNA integrity evaluation (TUNEL), anti-sperm antibodies (ASA) testing, sex hormone profile evaluation (Total testosterone, LH, FSH). In addition, all patients were administered International Index of Erectile Function questionnaire (IIEF-15). Sperm parameters were compared with two age-matched healthy pre-COVID-19 control groups of normozoospermic (CTR1) and primary infertile (CTR2) subjects. Results Median values of semen parameters from recovered SARS-CoV-2 subjects were within WHO 2010 fifth percentile. Mean percentage of sperm DNA fragmentation (%SDF) was 14.1 ± 7.0%. Gelatin Agglutination Test ( GAT ) was positive in 3.9% of blood serum samples, but no positive semen plasma sample was found. Only five subjects (6.2%) had total testosterone levels below the laboratory reference range. Mean bilateral testicular volume was 31.5 ± 9.6 ml. Erectile dysfunction was detected in 30% of subjects. Conclusion Our data remark that COVID-19 does not seem to cause direct damage to the testicular function, while indirect damage appears to be transient. It is possible to counsel infertile couples to postpone the research of parenthood or ART procedures around three months after recovery from the infection.