Flow diversion with the Pipeline Embolization Device has emerged as an attractive treatment for cerebral aneurysms. Processes involved in aneurysm occlusion include changes in intra-aneurysmal ...hemodynamics and endothelialization of the device. Here, we call attention to a radiographic sign not previously reported that is detected in incompletely occluded aneurysms after treatment with the Pipeline Embolization Device at angiographic follow-up and referred to as the "collar sign."
A retrospective review of all patients who underwent placement of a Pipeline Embolization Device for cerebral aneurysms between January 2014 and May 2016 was performed. All aneurysms found to show the collar sign at follow-up were included. Optical coherence tomography was performed in 1 case.
One hundred thirty-five aneurysms were treated in 115 patients. At angiographic follow-up, 17 (10.7%) aneurysms were found to be incompletely occluded. Ten (58.8%) of these aneurysms (average diameter, 7.9 ± 5.0 mm) were found to have the collar sign at angiographic follow-up (average, 5.5 ± 1.0 months). Four (40.0%) of the aneurysms underwent a second angiographic follow-up (average, 11.0 ± 0.9 months) after treatment, and again were incompletely occluded and showing the collar sign. Two patients underwent retreatment with a second Pipeline Embolization Device. Optical coherence tomography showed great variability of endothelialization at the proximal end of the Pipeline Embolization Device.
The collar sign appears to be indicative of endothelialization, but continued blood flow into the aneurysm. This is unusual given the processes involved in aneurysm occlusion after placement of the Pipeline Embolization Device and has not been previously reported.
Wellness during the pandemic Gould, Lisa; Mann, Colin; Gupta, R. Rishi ...
Canadian journal of ophthalmology,
06/2020, Letnik:
55, Številka:
3
Journal Article
We study the impact of national culture on initial public offerings (IPOs) - an important entrepreneurial activity through examining and providing empirical evidence of the proclivity for ...entrepreneurial firms situated across cultural contexts to seek legitimacy through floating IPOs. Informal institutions like culturally embedded societal norms of entrepreneurial behaviors and expectations for retained earnings as well as societal preferences for discretionary free cash flows are presented as the legitimizing mechanisms for such actions. We examined 7654 IPOs that occurred between 2003 and 2012 (312 country-year observations) from 47 countries. The results showed that countries with high power distance, high collectivism, and long-term orientation were positively associated with higher levels of IPO activity. In addition, the IPO activity levels were found to be significantly lower when the aggregated Euclidean distance differences between individual country culture profiles (where all the six dimensions of Hofstede's national culture taxonomy were considered together) and the ideal country cultural profile were greater.
Acute amebic appendicitis in early pregnancy Aggarwal, Monika; Sharma, Sanjay; Tewari, Rohit ...
Medical journal. Armed Forces India,
04/2022, Letnik:
78, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Parasitic infections of the intestine are a major health problem, which is found more prevalent in developing countries such as India. They are one of the important causes of morbidity and mortality ...among people all over the world. Acute amoebic appendicitis is a rare entity. We came across a case of acute appendicitis in a young pregnant woman, which revealed colonies of Entamoeba histolytica trophozoites in the mucosal epithelium and submucosal layer of the appendix with marked evidence of acute appendicitis. This report highlights acute appendicitis of amoebic origin and emphasises the importance of thorough examination of the appendix at various levels during histopathology and about the combined treatment of appendicectomy combined with antimicrobials as the treatment of choice. Appendicectomy removes the focus of infection, and antimicrobials reduce the incidence of septic complications.
The worldwide prevalence and risk factors for kidney stones in patients with fibrodysplasia ossificans progressiva (FOP) are unknown. We conducted a survey of 383 patient-members of the International ...Fibrodysplasia Ossificans Progressiva Association, comprising the entire global membership of the international FOP community. Two hundred seven patients from 31 nations and 6 continents (54%) responded. Nineteen of 207 respondents had kidney stones, revealing a worldwide prevalence of 9.2%. In a confirmatory follow-up study of subjects participating in a longitudinal FOP natural history study, 9 of 114 individuals reported a history of kidney stones (7.9%). In both study populations patients with kidney stones were found to be more functionally impaired compared to those without nephrolithiasis. The prevalence of kidney stones in the adult FOP population of the Unites States was 15.8% (9/57 individuals) compared to a sex- and age-weighted prevalence of 4.5% (p=4×10−5) in the general population. Although geographical variation exists, patients with FOP have an approximately three-fold greater prevalence of kidney stones than the general population. This unusually high prevalence may be due to high bone turnover from chronic immobilization, or to unknown mechanistic effects of the activating FOP mutation in activin A receptor, type I/activin-like kinase-2 (ACVR1/ALK2), increasing the disease burden and morbidity in this already disabling condition.
We present multimodal imaging of an interesting case of a 78-year-old man who developed large ciliochoroidal detachments and macular subretinal and intraretinal fluid in the right eye following ...bilateral neodymium-doped yttrium aluminium garnet (Nd:YAG) laser peripheral iridotomies (LPIs).
The ciliochoroidal detachments developed in the absence of documented post-procedure hypotony or intraocular pressure fluctuation. Ultrasound biomicroscopy (UBM) confirmed serous ciliochoroidal detachment. There are a small number of cases of ciliochoroidal detachments developing after peripheral iridotomy, but these have involved either argon laser, significant decrease in intraocular pressure, or underlying ocular conditions or structural abnormalities, such as Vogt-Koyanagi-Harada (VKH) or nanophthalmos.
Serous ciliochoroidal detachments following the relatively non-invasive procedure of LPI are rare occurrences. We present our case in hopes of increasing awareness of this potential acute complication. We also discuss the diagnostic challenges of this unique case, the extensive work up, and current status of the patient.
Intimin is an essential adhesin of attaching and effacing organisms such as entropathogenic Escherichia coli. It is also the prototype of type Ve secretion or inverse autotransport, where the ...extracellular C-terminal region or passenger is exported with the help of an N-terminal transmembrane β-barrel domain. We recently reported a stalled secretion intermediate of intimin, where the passenger is located in the periplasm but the β-barrel is already inserted into the membrane. Stalling of this mutant is due to the insertion of an epitope tag at the very N terminus of the passenger. Here, we examined how this insertion disrupts autotransport and found that it causes misfolding of the N-terminal immunoglobulin (Ig)-like domain D00. We could also stall the secretion by making an internal deletion in D00, and introducing the epitope tag into the second Ig-like domain, D0, also resulted in reduced passenger secretion. In contrast to many classical autotransporters, where a proximal folding core in the passenger is required for secretion, the D00 domain is dispensable, as the passenger of an intimin mutant lacking D00 entirely is efficiently exported. Furthermore, the D00 domain is slightly less stable than the D0 and D1 domains, unfolding at ∼200 piconewtons (pN) compared with ∼250 pN for D0 and D1 domains as measured by atomic force microscopy. Our results support a model where the secretion of the passenger is driven by sequential folding of the extracellular Ig-like domains, leading to vectorial transport of the passenger domain across the outer membrane in an N to C direction.
In the context of high-energy physics, the use of Nb 3 Sn superconducting magnets as a cost-effective and reliable technology depends on improvements in the following areas: long development and ...manufacturing cycles, conductor degradation after thermal cycling, long training, as well as a demonstration in accelerator magnets with a beam aperture of the full potential of modern Nb 3 Sn conductors. In short, performance, robustness, and cost are the three issues to be addressed. The Magnet Development project (MagDev) of the Swiss Accelerator Research and Technology initiative (CHART) at the Paul Scherrer Institute (PSI) aims to contribute to the solutions to each of these issues, re-thinking the manufacturing and design process. In our program, every innovation is to be validated by means of a panoply of fast-turnaround tools: from non-powered and powered samples and coils, tested under background field, to low-field subscale magnets and high field short prototypes. This work presents one element in this panoply of R&D vehicles: a stress-managed Nb 3 Sn coil called BigBOX, impregnated with paraffin wax, and tested, through a collaboration with the Magnet Development Program of the United States (US-MDP), in the background field of Brookhaven National Laboratory (BNL)'s common coils dipole DCC17.
Ring resonators provide a means of filtering specific wavelengths from a waveguide, and optionally dropping the filtered wavelengths into a second waveguide. Both of these features are potentially ...useful for astronomical instruments. In this paper we focus on their use as notch filters to remove the signal from atmospheric OH emission lines from astronomical spectra. We derive the design requirements for ring resonators for OH suppression from theory and finite difference time domain simulations. We find that rings with small radii (< 10 μm) are required to provide an adequate free spectral range, leading to high index contrast materials such as Si and Si
N
. Critically coupled rings with high self-coupling coefficients should provide the necessary Q factors, suppression depth, and throughput for efficient OH suppression, but will require post-inscription tuning of the coupling and the resonant wavelengths. The overall prospects for the use of ring resonators in astronomical instruments is promising, provided efficient fibre-chip coupling can be achieved.
•Asphaltenes were pyrolysed in an entrained flow reactor at varying conditions.•Global gasification reactivity of chars obtained from pyrolysis decreased with increase in temperature.•Changes in char ...structure and composition could explain the variation in reactivity.•Increase in residence time had marginal decrease in char reactivity.
Integration of solvent deasphalting and asphaltenes gasification has been reported as a convenient alternative to coker based upgrading of bitumen, derived from oil sands. However, very limited work has been carried out on pyrolysis and gasification of asphaltenes at entrained flow conditions. The present study aims at addressing this gap, and provides a better understanding of the major intermediate in gasification process – char. Chars were prepared at different operating conditions in an atmospheric entrained flow reactor. Extensive characterization techniques were used to identify the changes in morphology, structure and composition of chars. We estimated the global gasification reactivity of chars with steam and CO2. Chars exhibited an internally hollow structure with porous walls. The nominal size of individual char particles and degree of fragmentation were greatly influenced by the operating conditions. H/C ratio, aromaticity and macro-porosity of chars increased with an increase in operating temperature, while content of heteroatoms and global reactivity showed a gradual decrease. Increase in residence time had marginal effect on char composition, morphology and global reactivity. V and Ni tend to accumulate in chars; however, their effect on global reactivity could not be established.
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