Outcomes of Preoperative Transophthalmic Artery Embolization of Meningiomas: A Systematic Review with a Focus on Embolization Agent.

BACKGROUND: Transophthalmic artery embolization of intracranial meningiomas is thought to be associated with a high complication risk. PURPOSE: With advances in endovascular techniques, we systematically reviewed the current literature to improve our understanding of the safety and efficacy of transophthalmic artery embolization of intracranial meningiomas. DATA SOURCES: We performed a systematic search using PubMed from inception until August 3, 2022. STUDY SELECTION: Twelve studies with 28 patients with intracranial meningiomas embolized through the transophthalmic artery were included. DATA ANALYSIS: Baseline and technical characteristics and clinical and safety outcomes were collected. No statistical analysis was conducted. DATA SYNTHESIS: The average age of 27 patients was 49.5 (SD, 13) years. Eighteen (69%) meningiomas were located in the anterior cranial fossa, and 8 (31%), in the sphenoid ridge/wing. Polyvinyl alcohol particles were most commonly (n = 8, 31%) used to preoperatively embolize meningiomas, followed by n-BCA in 6 (23%), Onyx in 6 (23%), Gelfoam in 5 (19%), and coils in 1 patient (4%). Complete embolization of the target meningioma feeders was reported in 8 (47%) of 17 patients; partial embolization, in 6 (32%); and suboptimal embolization, in 3 (18%). The endovascular complication rate was 16% (4 of 25), which included visual impairment in 3 (12%) patients. LIMITATIONS: Selection and publication biases were limitations. CONCLUSIONS: Transophthalmic artery embolization of intracranial meningiomas is feasible but is associated with a non-negligible complication rate.

Predictors of combat training attrition in Israel Defense Forces soldiers.

BACKGROUND: Attrition from combat service carries significant organizational and personal ramifications, but predicting factors associated with attrition remains challenging. AIMS: To evaluate medical and psychosocial factors associated with attrition from basic combat training (BCT) in the Israel Defense Forces (IDF). In addition, we identify subsets of the recruit population which exhibit certain trends in terms of medical corresponding with a high risk of attrition. METHODS: A cross-sectional study of IDF combat trainees undergoing infantry BCT between 2012 and 2017. Data were collected from the soldiers' electronic medical and administrative records. We used multivariable logistic regression and the SAS® decision-tree tool to analyse key predictive factors for attrition. RESULTS: A total of 46 472 soldiers enlisted to BCT during the research period. The mean body mass index (BMI) was 21.8 (SD 3.54). The overall attrition rate was 10%. The following factors were associated with attrition from BCT: ethnicity (P < 0.01), BMI (P < 0.01), pre-enlisting motivation score (P < 0.01) and the number of mental health officer visits (P < 0.01). Using a decision-tree model, we found a high attrition rate among soldiers who had >5.2 to primary care physician visits (11% attrition rate versus 3%) or more than 11 sick leave days (59% versus 19%). CONCLUSIONS: This study sheds light on unique measures relating to attrition. Attrition is associated with several demographic and psychosocial factors. Early prediction of motivation and monitoring of healthcare utilization may enable early identification and focused interventions targeting soldiers at high risk for attrition. These findings need to be further translated into actionable directives and further investigations.

Tumor Embolization through Meningohypophyseal and Inferolateral Trunks is Safe and Effective.

BACKGROUND AND PURPOSE: Skull base tumors are commonly supplied by dural branches of the meningohypophyseal and inferolateral trunks. Embolization through these arteries is often avoided due to technical challenges and inherent risks; however, successful embolization can be a valuable surgical adjunct. We aimed to review the success and complications in our series of tumor embolizations through the meningohypophyseal and inferolateral trunks. MATERIALS AND METHODS: We performed a retrospective review of patients with tumor treated with preoperative embolization at our institution between 2010 and 2020. We reviewed the following data: patients' demographics, tumor characteristics, endovascular embolization variables, and surgical results including estimated blood loss, the need for transfusion, and operative time. RESULTS: Among 155 tumor embolization cases, we identified 14 patients in whom tumor embolization was performed using the meningohypophyseal (n = 13) or inferolateral (n = 4) trunk. In this group of patients, on average, 79% of tumors were embolized. No mortality or morbidity from the embolization procedure was observed in this subgroup of patients. The average estimated blood loss in the operation was 395 mL (range, 200-750 mL). None of the patients required a transfusion, and the average operative time was 7.3 hours. CONCLUSIONS: Some skull base tumors necessitate embolization through ICA branches such as the meningohypophyseal and inferolateral trunks. Our series demonstrates that an effective and safe embolization may be performed through these routes.

Study of the Effect of Reflections on High-Power, 110 GHz Pulsed Gyrotron Operation.

The effect of reflection is studied experimentally and theoretically on a high-power 110 GHz gyrotron operating in the TE22,6 mode in 3 µs pulses at 96 kV, 40 A. The experimental setup allows variation of the reflected power from 0 to 33 % over a range of gyrotron operating conditions. The phase of the reflection is varied by translating the reflector along the axis. Operating at a higher efficiency point, at 4:40 T with 940 kW of output power, reflected power exceeding 11% causes a switch from operation in the TE22,6 to simultaneous operation in the TE22,6 and TE21,6 modes with a large decrease of the total gyrotron output power. This switching effect is in good agreement with simulations using the MAGY code. Operating at a more stable point, 4:44 T with 580 kW of output power, when the reflection is increased, the output power remains in the TE22,6 mode but it decreases monotonically with increasing reflection, dropping to 200 kW at 33% reflection. Furthermore, at a reflection above 22%, a power modulation at 25 to 30 MHz is observed, independent of the phase of the reflected wave. Such a modulated signal may be useful in spectroscopic and other applications.

Arterial and Venous 3D Fusion AV-3D-DSA: A Novel Approach to Cerebrovascular Neuroimaging.

DSA is the standard imaging technique for evaluation of cerebrovascular conditions. However, One drawback is its limitation in depicting a single angiographic phase at a time. We describe a new 3D-DSA algorithm, which we call arterial and venous-3D-DSA, which allows the concurrent yet distinct display of the arterial and venous structures, which may be useful for different clinical and educational purposes.

Public perceptions of antibiotic use on dairy farms in the United States.

There has been a global push for improved antimicrobial stewardship, including in animal agriculture, due to growing concerns about antimicrobial resistance. However, little is known about the general public's perceptions of antimicrobial use in animal agriculture. The aim of this study was to explore the US public's perceptions of antibiotic use in dairy farming and how these perceptions influence purchasing decisions. Data from the 2017 Cornell National Social Survey developed in collaboration with the Cornell Survey Research Institute were used to assess the public's perceptions. The Survey Research Institute of Cornell University (Ithaca, NY) administered the survey by telephone to a random sample of 1,000 adults in the continental United States. The survey collected information about perceptions of threat to human health posed by antibiotic use in cows on dairy farms and willingness to pay more for milk from cows raised without antibiotics, as well as several presumed explanatory variables, including respondents' knowledge of antibiotics, beliefs regarding cattle treatment in dairy farming, and 18 sociodemographic characteristics. Data were analyzed using logistic regression. Among respondents, 90.7% (n = 892/983) reported that antibiotic use on dairy farms posed some level of threat to human health and 71.5% (n = 580/811) indicated they would be willing to pay more for milk produced from cows raised without antibiotics. Respondents who believed that antibiotic use in dairy farming posed a moderate to high threat to human health were more likely to be female and report willingness to pay more for milk or not purchase milk. Additionally, consumers' willingness to pay more for milk from cattle raised without antibiotics was associated with the belief that antibiotic use posed some threat to human health, the belief that cows are treated better on organic dairy farms, an annual household income of $50,000 or greater, being born outside the United States, having a liberal social ideology, and being currently or formerly married. These results suggest that the general public's decisions as consumers of dairy products are associated with demographic factors in addition to perceptions of antibiotic use and cattle treatment in dairy farming. The rationale behind such perceptions should be further explored to facilitate consumers' informed decision making about antibiotic use in agriculture, links to cattle treatment, and associated willingness-to-pay attitudes.

Correction to: Study of the Effect of Reflections on High-Power, 110-GHz Pulsed Gyrotron Operation.

[This corrects the article PMC8291730.].

Dural Venous Channels: Hidden in Plain Sight-Reassessment of an Under-Recognized Entity.

BACKGROUND AND PURPOSE: Tentorial sinus venous channels within the tentorium cerebelli connecting various cerebellar and supratentorial veins, as well as the basal vein, to adjacent venous sinuses are a well-recognized entity. Also well-known are "dural lakes" at the vertex. However, the presence of similar channels in the supratentorial dura, serving as recipients of the Labbe, superficial temporal, and lateral and medial parieto-occipital veins, among others, appears to be underappreciated. Also under-recognized is the possible role of these channels in the angioarchitecture of certain high-grade dural fistulas. MATERIALS AND METHODS: A retrospective review of 100 consecutive angiographic studies was performed following identification of index cases to gather data on the angiographic and cross-sectional appearance, location, length, and other features. A review of 100 consecutive dural fistulas was also performed to identify those not directly involving a venous sinus. RESULTS: Supratentorial dural venous channels were found in 26% of angiograms. They have the same appearance as those in the tentorium cerebelli, a flattened, ovalized morphology owing to their course between 2 layers of the dura, in contradistinction to a rounded cross-section of cortical and bridging veins. They are best appreciated on angiography and volumetric postcontrast T1-weighted images. Ten dural fistulas not directly involving a venous sinus were identified, 6 tentorium cerebelli and 4 supratentorial. CONCLUSIONS: Supratentorial dural venous channels are an under-recognized entity. They may play a role in the angioarchitecture of dural arteriovenous fistulas that appear to drain directly into a cortical vein. We propose "dural venous channel" as a unifying name for these structures.

Cerebral Venous Thrombosis Associated with COVID-19.

Despite the severity of coronavirus disease 2019 (COVID-19) being more frequently related to acute respiratory distress syndrome and acute cardiac and renal injuries, thromboembolic events have been increasingly reported. We report a unique series of young patients with COVID-19 presenting with cerebral venous system thrombosis. Three patients younger than 41 years of age with confirmed Severe Acute Respiratory Syndrome coronavirus 2 (SARS-Cov-2) infection had neurologic findings related to cerebral venous thrombosis. They were admitted during the short period of 10 days between March and April 2020 and were managed in an academic institution in a large city. One patient had thrombosis in both the superficial and deep systems; another had involvement of the straight sinus, vein of Galen, and internal cerebral veins; and a third patient had thrombosis of the deep medullary veins. Two patients presented with hemorrhagic venous infarcts. The median time from COVID-19 symptoms to a thrombotic event was 7 days (range, 2-7 days). One patient was diagnosed with new-onset diabetic ketoacidosis, and another one used oral contraceptive pills. Two patients were managed with both hydroxychloroquine and azithromycin; one was treated with lopinavir-ritonavir. All patients had a fatal outcome. Severe and potentially fatal deep cerebral thrombosis may complicate the initial clinical presentation of COVID-19. We urge awareness of this atypical manifestation.

A dynamical model of oncotripsy by mechanical cell fatigue: selective cancer cell ablation by low-intensity pulsed ultrasound.

The method of oncotripsy, first proposed in Heyden & Ortiz (Heyden & Ortiz 2016 J. Mech. Phys. Solids 92, 164-175 (doi:10.1016/j.jmps.2016.04.016)), exploits aberrations in the material properties and morphology of cancerous cells in order to ablate them selectively by means of tuned low-intensity pulsed ultrasound. We propose the dynamical model of oncotripsy that follows as an application of cell dynamics, statistical mechanical theory of network elasticity and 'birth-death' kinetics to describe the processes of damage and repair of the cytoskeleton. We also develop a reduced dynamical model that approximates the three-dimensional dynamics of the cell and facilitates parametric studies, including sensitivity analysis and process optimization. We show that the dynamical model predicts-and provides a conceptual basis for understanding-the oncotripsy effect and other trends in the data of Mittelstein et al. (Mittelstein et al. 2019 Appl. Phys. Lett. 116, 013701 (doi:10.1063/1.5128627)), for cells in suspension, including the dependence of cell-death curves on cell and process parameters.

Measurement of Dielectric Multipactor Thresholds at 110 GHz.

We report experimental measurements of the threshold for multipactor discharges on dielectric surfaces at 110 GHz. Multipactor was studied in two geometries: electric field polarized parallel to or perpendicular to the sample surface. Measured multipactor thresholds ranged from 15 to 34 MV/m, more than 10 times higher than those found at conventional microwave frequencies. Measured thresholds were compared with prior data at lower frequencies, showing agreement with theoretical predictions that thresholds increase linearly with frequency. Measurements of the rf power dissipated in the multipactor show low dissipation (≤1%) for the parallel electric field case, but very strong dissipation for the perpendicular case, also in agreement with theoretical predictions. The agreement between experiment and theory over a wide range of frequencies provides a strong basis for the understanding of dielectric multipactor discharges.

What should guide our patient management of vulvovaginal atrophy?

Genitourinary syndrome of menopause including vulvovaginal atrophy is commonly experienced by postmenopausal women, reducing their quality of life. The aim of this review is to assess current treatment options within the framework of recent management guidelines. Recommendations include use of treatments addressing both symptoms and the underlying pathophysiology, and proactive patient discussion. Both prescription and non-prescription options are recognized, including non-hormone-based approaches. Local therapy is preferable in the primary treatment of genitourinary syndrome of menopause symptoms as risk of adverse events is reduced, although long-term safety data are limited. Management of patients with a history of breast cancer requires careful consideration, although estrogen therapy has not been associated with increased risk of breast cancer or of recurrence. Treatment should consider ongoing cancer therapy. As multiple, comparable options exist, treatment choice may be due to experience and patient preference. Best management requires effective patient-physician communication and shared decision-making.

Subterahertz Photonic Crystal Klystron Amplifier.

This Letter reports the successful experimental demonstration of amplification of subterahertz radiation in a klystron with photonic crystal cavities. The klystron has six cavities, with each cavity having a series of oversized photonic crystal cells made up of a 5×3 array of square posts. The center post is removed from each cell to form a highly oversized (0.8 mm∼λ/4) beam tunnel, with power coupling from cell to cell through the tunnel. The pulsed electron beam is operated at 23.5 kV, 330 mA in a 0.5 T solenoidal field. At 93.7 GHz, a small-signal gain of 26 dB and a saturated output power of 30 W are obtained. Experimental results are in very good agreement with the predictions of a particle-in-cell code. The successful achievement of high gain operation of a photonic crystal klystron amplifier is promising for the future extension of klystron operation well into the terahertz frequency region.

Toward Better Understanding of Flow Diversion in Bifurcation Aneurysms.

BACKGROUND AND PURPOSE: Flow diversion is being increasingly used to treat bifurcation aneurysms. Empiric approaches have generally led to encouraging results, and a growing body of animal and ex vivo literature addresses the fate of target aneurysms and covered branches. Our prior investigations highlighted the dynamic nature of metal coverage provided by the Pipeline Embolization Device and suggested strategies for creating optimal single and multidevice constructs. We now address the geometric and hemodynamic aspects of jailing branch vessels and neighboring target aneurysms. MATERIALS AND METHODS: Fundamental electric and fluid dynamics principles were applied to generate equations describing the relationships between changes in flow and the degree of vessel coverage in settings of variable collateral support to the jailed territory. Given the high complexity of baseline and posttreatment fluid dynamics, in vivo, we studied a simplified hypothetic system with minimum assumptions to generate the most conservative outcomes. RESULTS: In the acute setting, Pipeline Embolization Devices modify flow in covered branches, principally dependent on the amount of coverage, the efficiency of collateral support, and intrinsic resistance of the covered parenchymal territory. Up to 30% metal coverage of any branch territory is very likely to be well-tolerated regardless of device or artery size or the availability of immediate collateral support, provided, however, that no acute thrombus forms to further reduce jailed territory perfusion. CONCLUSIONS: Basic hemodynamic principles support the safety of branch coverage during aneurysm treatment with the Pipeline Embolization Device. Rational strategies to build bifurcation constructs are feasible.

Spinal Instrumentation Rescue with Cement Augmentation.

BACKGROUND AND PURPOSE: Altered biomechanics or bone fragility or both contribute to spine instrumentation failure. Although revision surgery is frequently required, minimally invasive alternatives may be feasible. We report the largest to-date series of percutaneous fluoroscopically guided vertebral cement augmentation procedures to address feasibility, safety, results and a variety of spinal instrumentation failure conditions. MATERIALS AND METHODS: A consecutive series of 31 fluoroscopically guided vertebral augmentation procedures in 29 patients were performed to address screw loosening (42 screws), cage subsidence (7 cages), and fracture within (12 cases) or adjacent to (11 cases) the instrumented segment. Instrumentation failure was deemed clinically relevant when resulting in pain or jeopardizing spinal biomechanical stability. The main study end point was the rate of revision surgery avoidance; feasibility and safety were assessed by prospective recording of periprocedural technical and clinical complications; and clinical effect was measured at 1 month with the Patient Global Impression of Change score. RESULTS: All except 1 procedure was technically feasible. No periprocedural complications occurred. Clinical and radiologic follow-up was available in 28 patients (median, 16 months) and 30 procedures. Revision surgery was avoided in 23/28 (82%) patients, and a global clinical benefit (Patient Global Impression of Change, 5-7) was reported in 26/30 (87%) cases at 1-month follow-up, while no substantial change (Patient Global Impression of Change, 4) was reported in 3/30 (10%), and worsening status (Patient Global Impression of Change, 3), in 1/30 (3%). CONCLUSIONS: Our experience supports the feasibility of percutaneous vertebral augmentation in the treatment of several clinically relevant spinal instrumentation failure conditions, with excellent safety and efficacy profiles, both in avoidance of revision surgery and for pain palliation.

Toward a Better Understanding of Dural Arteriovenous Fistula Angioarchitecture: Superselective Transvenous Embolization of a Sigmoid Common Arterial Collector.

BACKGROUND AND PURPOSE: Our aim was to propose a conceptually new angioarchitectural model of some dural arteriovenous fistulas based on subset analysis of transverse and sigmoid type lesions. The "common collector" notion argues for convergence of multiple smaller caliber arterial vessels on a common arterial collector vessel within the sinus wall. Communication of this single collector (or constellation of terminal collectors) with the sinus proper defines the site of arteriovenous fistula, which can be closed by highly targeted embolization, preserving the sinus and avoiding unnecessary permeation of indirect arterial feeders. MATERIALS AND METHODS: One hundred consecutive dural arteriovenous shunts were examined. Thirty-six transverse/sigmoid fistulas were identified within this group and analyzed for the presence of a common arterial collector as well as other parameters, including demographics, grade, treatment approach, and outcome. RESULTS: A common collector was identified in nearly all Cognard type I lesions (15 fistulas with 14 single collector vessels seen) and progressively less frequently in higher grade fistulas. Identification of the common collector requires careful angiographic analysis, including supraselective and intraprocedural angiographies during treatment, and final embolic material morphology. CONCLUSIONS: Detailed evaluation of imaging studies allows frequent identification of a vascular channel in the sinus wall, which we argue reflects a compound, common arterial channel (rather than a venous collector) with 1 or several discrete fistulous points between this vessel and the sinus proper. Targeted closure of this channel is often feasible, with sinus preservation and avoidance of embolic material penetration into arteries remote from fistula site.

CD84 mediates CLL-microenvironment interactions.

Chronic lymphocytic leukemia (CLL) is a malignant disease of small mature lymphocytes. Signals from the CLL microenvironment promote progression of the disease and induce drug resistance. This phenomenon is largely dependent on direct contact between the malignant B cells and stromal cells. CD84 belongs to the signaling lymphocyte activation molecule family of immunoreceptors, which self-associates, forming an orthogonal homophilic dimer. We therefore hypothesized that CD84 may bridge between CLL cells and their microenvironment, promoting cell survival. Our in vitro results show that CD84 expressed on CLL cells interact with CD84 expressed on cells in their microenvironment, inducing cell survival in both sides. Blocking CD84 in vitro and in vivo disrupt the interaction of CLL cells with their microenvironment, resulting in induced cell death. Thus, our findings suggest novel therapeutic strategies based on the blockade of this CD84-dependent survival pathway.

[Proteomic analysis of contaminants in recombinant membrane hemeproteins expressed in E. coli and isolated by metal affinity chromatography].

Contaminating proteins have been identified by "shotgun" proteomic analysis in 14 recombinant preparations of human membrane heme- and flavoproteins expressed in Escherichia coli and purified by immobilized metal ion affinity chromatography. Immobilized metal ion affinity chromatography of ten proteins was performed on Ni2+-NTA-sepharose 6B, and the remaining four proteins were purified by ligand affinity chromatography on 2',5'-ADP-sepharose 4B. Proteomic analysis allowed to detect 50 protein impurities from E. coli. The most common contaminant was Elongation factor Tu2. It is characterized by a large dipole moment and a cluster arrangement of acidic amino acid residues that mediate the specific interaction with the sorbent. Peptidyl prolyl-cis-trans isomerase SlyD, glutamine-fructose-6-phosphate aminotransferase, and catalase HPII that contained repeating HxH, QxQ, and RxR fragments capable of specific interaction with the sorbent were identified among the protein contaminants as well. GroL/GroS chaperonins were probably copurified due to the formation of complexes with the target proteins. The Ni2+ cations leakage from the sorbent during lead to formation of free carboxyl groups that is the reason of cation exchanger properties of the sorbent. This was the putative reason for the copurification of basic proteins, such as the ribosomal proteins of E. coli and the widely occurring uncharacterized protein YqjD. The results of the analysis revealed variation in the contaminant composition related to the type of protein expressed. This is probably related to the reaction of E. coli cell proteome to the expression of a foreign protein. We concluded that the nature of the protein contaminants in a preparation of a recombinant protein purified by immobilized metal ion affinity chromatography on a certain sorbent could be predicted if information on the host cell proteome were available.