We present spectroscopic and photometric observations for the Type Ibn supernova (SN) dubbed PSN J07285387+3349106. Using data provided by amateur astronomers, we monitored the photometric rise of ...the SN to maximum light, occurred on 2015 February 18.8 ut (JDmax(V) = 245 7072.0 ± 0.8). PSN J07285387+3349106 exploded in the inner region of an infrared luminous galaxy, and is the most reddened SN Ibn discovered so far. We apply multiple methods to derive the total reddening to the SN, and determine a total colour excess E(B − V)tot = 0.99 ± 0.48 mag. Accounting for the reddening correction, which is affected by a large uncertainty, we estimate a peak absolute magnitude of M
V
= −20.30 ± 1.50. The spectra are dominated by continuum emission at early phases, and He i lines with narrow P-Cygni profiles are detected. We also identify weak Fe iii and N ii features. All these lines show an absorption component which is blueshifted by about 900–1000 km s−1. The spectra also show relatively broad He i line wings with low contrast, which extend to above 3000 km s−1. From about two weeks past maximum, broad lines of O i, Mg ii and the Ca ii near-infrared triplet are identified. The composition and the expansion velocity of the circumstellar material, and the presence of He i and α-elements in the SN ejecta indicate that PSN J07285387+3349106 was produced by the core collapse of a stripped-envelope star. We suggest that the precursor was WNE-type Wolf–Rayet star in its dense, He-rich circumstellar cocoon.
Intra-arterial chemotherapy for retinoblastoma is not always a straightforward procedure, and it may require an adaptable approach. This study illustrates strategies used when the ophthalmic artery ...is difficult to catheterize or not visible, and it ascertains the effectiveness and safety of these strategies.
A retrospective study was performed on a series of 108 eyes affected by intraocular retinoblastoma and selected for intra-arterial chemotherapy (follow-up range, 6-82 months). We recognized 3 different patterns of drug delivery: a fixed pattern through the ophthalmic artery, a fixed pattern through branches of the external carotid artery, and a variable pattern through either the ophthalmic or the external carotid artery.
We performed 448 sessions of intra-arterial chemotherapy, 83.70% of them through the ophthalmic artery and 16.29% via the external carotid artery. In 24.52% of eyes, the procedure was performed at least once through branches of the external carotid artery. In 73 eyes, the pattern of drug delivery was fixed through the ophthalmic artery; for 9 eyes, it was fixed through branches of the external carotid artery; and for 17 eyes, the pattern was variable. Statistical analysis did not show any significant difference in the clinical outcome of the eyes (remission versus enucleation) treated with different patterns of drug delivery. Adverse events could not be correlated with any particular pattern.
Alternative routes of intra-arterial chemotherapy for intraocular retinoblastoma appear in the short term as effective and safe as the traditional drug infusion through the ophthalmic artery.
Aspiration thrombectomy of large vessel occlusions has made a comeback among recanalization techniques thanks to recent advances in catheter technology resulting in faster recanalization and ...promising clinical results when used either alone or as an adjunct to stent retriever. This multicenter retrospective study reports angiographic data, complications, and clinical outcome in patients treated with aspiration thrombectomy as the first-line option.
We analysed the clinical and procedural data of patients treated from January 2014 to March 2015. Recanalization was assessed according to the Thrombolysis in Cerebral Infarction score. Clinical outcome was evaluated at discharge and after 3 months.
Overall, 152 patients (mean age 68 years) were treated. Sites of occlusion were 90.8% anterior circulation (including 16.4% tandem extracranial/intracranial occlusions) and 9.2% basilar artery. In 79 patients administration of intravenous tissue plasminogen activator was attempted. Recanalization of the target vessel was obtained in 115/152 cases (75.6%) whereas direct aspiration alone was successful in 83/152 cases (54.6%) with an average puncture to revascularization time of 44.67 min. Symptomatic intracranial hemorrhage occurred in 7.8% and embolization to new territories in 1.9%. 77 patients (50.6%) had a good outcome at 90-day follow-up: 55/96 in the direct aspiration alone group and 22/56 in the aspiration-stent retriever group.
Direct aspiration thrombectomy appears a feasible technique with good revascularization results achieved in more than half the patients. In light of the self-reported data, inhomogeneous patient selection, absence of a core imaging laboratory, and a non-standardized approach, the results should be validated in a larger trial.
The autonomic nervous system maintains constant cerebral venous blood outflow in changing positions. Alterations in cerebral autoregulation can be revealed by postural changes at quantitative color ...Doppler sonography. The aim of this study was to reach an optimal cutoff value of the difference between the cerebral venous blood outflow in the supine and seated positions that can discriminate healthy controls from patients with multiple sclerosis and those with other neurologic diseases and to evaluate its specificity, sensitivity, and diagnostic accuracy.
One hundred fifteen subjects (54 with MS, 31 healthy controls, 30 with other neurologic diseases) underwent a blinded quantitative color Doppler sonography evaluation of cerebral venous blood outflow in the supine and sitting positions. An optimal difference value between the supine and sitting positions of the cerebral venous blood outflow cutoff value was sought.
The difference value between supine and sitting positions of the cerebral venous blood outflow was ≤ 503.24 in 38/54 (70.37%) patients with MS, 9/31 (29.03%) healthy controls, and 13/30 (43.33%) subjects with other neurological diseases. A difference value between supine and sitting positions of the cerebral venous blood outflow at a 503.24 cutoff reached a sensitivity at 70.37%, a 70.96% specificity, a 80.85% positive predictive value, and a 57.89% negative predictive value; the quantitative color Doppler sonography parameters yielded significant differences. The difference value between supine and sitting positions of cerebral venous blood outflow ≤ 503.24 assessed the significant difference between MS versus other neurological diseases.
Alteration of cerebral venous blood outflow discriminated MS versus other neurologic diseases and MS versus healthy controls. The difference value between supine and sitting positions of cerebral venous blood outflow ≤ 503.24 was statistically associated with MS.
Background
For intracranial large vessel occlusion in acute ischemic stroke (AIS), a high degree of revascularization in the minimal amount of time predicts good outcomes. Recently, different studies ...have shown that the direct aspiration first pass technique (ADAPT technique) for AIS obtains high recanalization rates, fast interventions and low costs when it works as first attempt. This study retrospectively describes revascularization efficacy, duration of procedure, intra and post-procedural complications, early and after 90-days clinical outcome in a group of patients who underwent ADAPT as the primary endovascular approach, eventually followed by stent retriever thrombectomy, for recanalization of large vessels in the anterior circulation.
Materials and methods
We analyzed clinical and procedural data of patients treated from April 2014 to August 2015. Recanalization was assessed according to the Thrombolysis in Cerebral Infarction score. Clinical outcome was evaluated at discharge and after 3 months (modified Rankin Scale, mRS).
Results
Overall, 71 patients (mean age of 69.7 years) were treated. Sites of occlusion were anterior circulation (including seven tandem extracranial-intracranial occlusions). In 39 patients i.v. rtPA was attempted. Recanalization of the target vessel was obtained in 87.3% of cases whereas direct aspiration alone was successful in 46/71cases (64.8%) with an average puncture-to-revascularization time of 43.1 minutes. Symptomatic intracranial hemorrhage occurred in 7.8% and embolization to new territories in 5.6%. In total, 38 patients (53.5%) had a good outcome at 90 days follow-up.
Conclusions
In our series, the manual thromboaspiration technique has been shown as fast and safe, with good rates of vessel revascularization in 87.3% of patients and neurological outcome <3 mRS in 53.5% of patients.
Endovascular aneurysm repair (EVAR) is a minimally invasive treatment that can be offered to most patients with an aortic aneurysm. Patients who are rejected from standard EVAR often have more ...extensive aortic pathology and more medical comorbidities. The advent of fenestrated and branched stent grafts gives us an opportunity to treat the most demanding aortic aneurysms endovascularly. Fenestrated stent-grafts, however, are costly and time-consuming to manufacture, which limits their applicability, especially in the emergency setting. The chimney graft is a stent placed parallel to the aortic stent-graft to preserve flow to a vital aortic branch that was overstented to obtain an adequate seal. The technique can be used as a planned operation but also as a rescue procedure to salvage a side branch unintentionally covered during EVAR. As visceral branches of the aorta are usually directed caudally these vessels are, therefore, preferably catheterized from a brachial approach. We describe a case of a successful positioning of the chimney graft using only the femoral approach. The only femoral approach to position a renal chimney graft isn't recommended for the routine procedure but it is proved to be useful in selected case and when other treatment options are excluded.
Endovascular aneurysm repair (EVAR) offers a minimally invasive treatment to patients with improved short-term and similar mid-term results compared to conventional, open repair. Approximately 20% of ...patients have an aneurysm neck morphology inadequate for a standard stent-graft and requires an endograft to cross vital aortic side branches to achieve a seal. This work describes the promising single center preliminary results in the management of juxtarenal aortic aneurysm using E-vita stent-graft.
Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales
. This variability seems mostly random, although some ...quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare
in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet
, plasma instabilities
or orbital motion in an accretion disc
. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref.
). BL Lac, the prototype of a subclass of blazars
, is powered by a 1.7 × 10
M
(ref.
) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref.
)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities
near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.
Abstract We present the largest optical photometry compilation of Gamma-Ray Bursts (GRBs) with redshifts (z). We include 64813 observations of 535 events (including upper limits) from 28 February ...1997 to 18 August 2023. We also present a user-friendly web tool grbLC which allows users to visualise photometry, coordinates, redshift, host galaxy extinction, and spectral indices for each event in our database. Furthermore, we have added a Gamma-ray Coordinate Network (GCN) scraper that can be used to collect data by gathering magnitudes from the GCNs. The web tool also includes a package for uniformly investigating colour evolution. We compute the optical spectral indices for 138 GRBs, for which we have at least 4 filters at the same epoch in our sample, and craft a procedure to distinguish between GRBs with and without colour evolution. By providing a uniform format and repository for the optical catalogue, this web-based archive is the first step towards unifying several community efforts to gather the photometric information for all GRBs with known redshifts. This catalogue will enable population studies by providing light curves (LCs) with better coverage since we have gathered data from different ground-based locations. Consequently, these LCs can be used to train future LC reconstructions for an extended inference of the redshift. The data gathering also allows us to fill some of the orbital gaps from Swift in crucial points of the LCs, e.g., at the end of the plateau emission or where a jet break is identified.
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