Clinical Features and Treatment Outcomes in Patients in Their Twenties with Ischemic Moyamoya Disease.

INTRODUCTION: Revascularization surgery is recommended for all pediatric patients with moyamoya disease (MMD) with ischemic symptoms because the brains of such patients are still developing. By contrast, no clear guidelines for selective revascularization surgery in adult patients (30 years or more) with ischemic presentation have been established. Regarding the age of initial onset of ischemic MMD, patients in their 20s are at the bottom of the distribution and this age group may share features with both adult and pediatric patients. The present prospective study aimed to clarify the clinical features and treatment outcomes of patients in their 20s (younger patients) with ischemic MMD compared with patients aged 30-60 years (older patients). METHODS: While patients with misery perfusion in the symptomatic cerebral hemisphere on 15O-positron emission tomography underwent combined surgery including direct and indirect revascularizations in the first study period and indirect revascularization alone in the second study period, patients without misery perfusion in that hemisphere received pharmacotherapy alone through the two study periods. Cerebral angiography via arterial catheterization and neuropsychological testing were performed before and after surgery. RESULTS: During 12 years, 12 younger patients were included and comprised 6% of all adult patients (194 patients). The incidence of misery perfusion in the affected hemisphere was significantly higher in younger (12/12 [100%]) than in older patients (57/182 [31%]) (p < 0.0001). No difference in the incidence of cerebral hyperperfusion syndrome and postoperatively declined cognition was seen between younger (2/5 [40%] and 2/5 [40%], respectively) and older (11/36 [31%] and 15/36 [42%], respectively) cerebral hemispheres undergoing combined revascularization surgery. No difference in the incidence of postoperatively formed collateral flows feeding more than one-third of the middle cerebral artery cortical territory on angiograms and postoperatively improved cognition was seen between younger (9/10 [90%] and 6/10 [60%], respectively) and older (18/22 [83%] and 14/22 [64%], respectively) cerebral hemispheres undergoing indirect revascularization surgery alone. CONCLUSION: Patients in their 20s with ischemic MMD always exhibit misery perfusion in the affected hemisphere, unlike older patients, and sometimes develop cerebral hyperperfusion syndrome after combined revascularization surgery, leading to cognitive decline, similar to older patients. Moreover, indirect revascularization surgery alone forms sufficient collateral circulation and restores cognitive function in patients in their 20s, similar to older patients.

Impact of postoperative cerebral hyperperfusion on 2-year cognitive outcomes of patients undergoing carotid endarterectomy.

OBJECTIVE: In 10% of patients undergoing carotid endarterectomy (CEA), the cognitive function declines postoperatively, primarily in association with postoperative cerebral hyperperfusion. In contrast, in the majority of patients undergoing CEA, long-term cognitive outcomes remain unclear. Furthermore, it is not known whether the decline in cognition due to cerebral hyperperfusion recovers on a long-term basis. This study aimed to understand how postoperative cerebral hyperperfusion affects the cognitive outcomes of patients who undergo CEA. METHODS: The participants in this prospective observational study were patients with internal carotid artery stenosis who underwent CEA. Cerebral hyperperfusion syndrome or asymptomatic cerebral hyperperfusion following CEA was determined based on brain perfusion SPECT scans and symptomatology before and after surgery. Neuropsychological testing was performed preoperatively, at 1-2 months postoperatively, and at 2 years postoperatively to investigate cognitive decline. RESULTS: A logistic regression analysis revealed that asymptomatic cerebral hyperperfusion (95% CI 13.0-84.5, p < 0.0001) and cerebral hyperperfusion syndrome (95% CI 449.7-14,237.4, p < 0.0001) were significantly associated with cognitive decline at 1-2 months postoperatively. The incidence of cognitive decline was significantly decreased at 2 years postoperatively (7%) in comparison to 1-2 months postoperatively (11%) (p = 0.0461). A logistic regression analysis also revealed that asymptomatic cerebral hyperperfusion (95% CI 3.7-36.7, p < 0.0001), cerebral hyperperfusion syndrome (95% CI 128.0-6183.6, p < 0.0001), and further strokes during the 2-year follow-up period (95% CI 1.5-78.7, p = 0.0167) were significantly associated with cognitive decline at 2 years postoperatively. The incidence of cognitive decline at 1-2 months postoperatively was significantly higher in patients with cerebral hyperperfusion syndrome (100%) than in those with asymptomatic cerebral hyperperfusion (44%) (p < 0.0001). No significant difference in incidence was observed in the former patients at 2 years postoperatively (88%), but significant reduction was found in patients with asymptomatic cerebral hyperperfusion and cognitive decline between the timepoints of 1-2 months postoperatively (100%) and 2 years postoperatively (39%) (p = 0.0001). CONCLUSIONS: Postoperative cerebral hyperperfusion causes prolonged cognitive decline at 2 years postoperatively in patients undergoing CEA.

Coil embolization of recurrent ruptured vertebral artery dissection through a marathon microcatheter: A case report.

A 56-year-old healthy woman presented with subarachnoid hemorrhage caused by ruptured vertebral artery dissecting aneurysm and was treated with internal trapping of the affected site including the aneurysm. She suffered rebleeding due to recanalization of the aneurysm 5 days after the first treatment. Because of the close proximity of the coil mass to the posterior inferior cerebellar artery (PICA) origin at first treatment, additional coil embolization by tight packing of the coil mass was planned. However, navigation of the microcatheter into the coil mass was challenging due to the tightly packed coil mass. Thus, a Marathon microcatheter, which has narrower outer diameter and is designed for liquid embolization, was used and successfully placed into the coil mass in an anterograde fashion. Thereafter, the DAC was advanced just proximal to the coil mass to reduce the kickback of the microcatheter during deployment of the coils and avoid the coil mass expansion toward the PICA origin, resulting in complete obliteration of the aneurysm with PICA preservation. Follow-up angiography performed 6 months after the second treatment showed complete obliteration of the aneurysm. The patient's course was uneventful after 1 year following the second treatment, with a modified Rankin Scale score of 1. Therefore, coil embolization through the tightly packed coil mass using a Marathon microcatheter is feasible. A low-profile DAC is also useful for enabling physicians to push the coil deployed through the flexible Marathon microcatheter.

Spontaneous orientation polarization of flavonoids.

Spontaneous orientation polarization (SOP) is macroscopic electric polarization that is attributed to a constant orientational degree of dipole moments of polar molecules on average. The phenomenon has been found in small molecules like H2O at low temperatures and π-conjugated molecules employed in organic light-emitting diodes. In this study, we demonstrate that a thin film of baicalein, a flavonoid compound found in natural products, exhibits SOP and resultant giant surface potential (GSP) exceeding 5500 mV at a film thickness of 100 nm. Vacuum-deposition of baicalein under high vacuum results in smooth and amorphous films, which enables the generation of GSP with a slope of 57 mV/nm in air, a value comparable to the representative of an organic semiconductor showing GSP, tris(8-hydroxyquinoline)aluminum(III) (Alq3). We also found the superior photostability of a baicalein film compared to an Alq3 film. These findings highlight the potential of baicalein in new applications to organic electronics.

Superatom Molecular Orbitals of Endohedral C82.

Understanding superatom molecular orbital (SAMO) states in fullerene derivatives has been in the limelight ever since the first discovery of SAMOs owing to the fundamental interest in this topic as well as to the possible applications in molecular switches and other organic electronics. Nevertheless, very few reports have been published on SAMO states of larger fullerenes so far. Using density functional theory, we attempt to partially remedy this situation by presenting a study on SAMO states in C82 and its Ca and Sc endohedrally doped derivatives, comparing results with previous relevant findings for C60. We find that C82 possesses higher SAMO energies compared to C60, as associated with the symmetry of the molecule, and that endohedral doping leads to energetically favorable side positions of Ca and Sc inside the C82 cage. Among the two, Sc@C82 has more stable SAMO states compared to Ca@C82 as reflected by the shift in the density of states, while the charge states are found to be similar. In the case of the monolayer form, the pz- and 2s-SAMO orbitals overlap with the nearest neighbors, causing parabolic band dispersion with the formation of near free electron states and that the SAMO state energies move closer to the Fermi energy compared to the related molecules. These findings provide promising information about the distribution of SAMO states in C82 fullerene, which can be further relevant in studies of SAMO states of higher fullerenes and for coming applications of these systems.

Artificial intelligence improves the accuracy of residents in the diagnosis of hip fractures: a multicenter study.

BACKGROUND: Less experienced clinicians sometimes make misdiagnosis of hip fractures. We developed computer-aided diagnosis (CAD) system for hip fractures on plain X-rays using a deep learning model trained on a large dataset. In this study, we examined whether the accuracy of the diagnosis of hip fracture of the residents could be improved by using this system. METHODS: A deep convolutional neural network approach was used for machine learning. Pytorch 1.3 and Fast.ai 1.0 were applied as frameworks, and an EfficientNet-B4 model (a pre-trained ImageNet model) was used. We handled the 5295 X-rays from the patients with femoral neck fracture or femoral trochanteric fracture from 2009 to 2019. We excluded cases in which the bilateral hips were not included within an image range, and cases of femoral shaft fracture and periprosthetic fracture. Finally, we included 5242 AP pelvic X-rays from 4851 cases. We divided these 5242 images into two images per image, and prepared 5242 images including fracture site and 5242 images without fracture site. Thus, a total of 10,484 images were used for machine learning. The accuracy, sensitivity, specificity, F-value, and area under the curve (AUC) were assessed. Gradient-weighted class activation mapping (Grad-CAM) was used to conceptualize the basis for the diagnosis of the fracture by the deep learning algorithm. Secondly, we conducted a controlled experiment with clinicians. Thirty-one residents;young doctors within 2 years of graduation from medical school who rotate through various specialties, were tested using 300 hip fracture images that were randomly extracted from the dataset. We evaluated the diagnostic accuracy with and without the use of the CAD system for each of the 300 images. RESULTS: The accuracy, sensitivity, specificity, F-value, and AUC were 96.1, 95.2, 96.9%, 0.961, and 0.99, respectively, with the correct diagnostic basis generated by Grad-CAM. In the controlled experiment, the diagnostic accuracy of the residents significantly improved when they used the CAD system. CONCLUSIONS: We developed a newly CAD system with a deep learning algorithm from a relatively large dataset from multiple institutions. Our system achieved high diagnostic performance. Our system improved the diagnostic accuracy of residents for hip fractures. LEVEL OF EVIDENCE: Level III, Foundational evidence, before-after study. CLINICAL RELEVANCE: high.

Antiviral Activity and Molecular Geometry of Some New Symmetrical Tris(aminoalkyl)amine Derivatives.

We report the preparation of new tripodal receptor-type C3- and CS-symmetrical molecules constructed on a tris(2-aminoethyl)amine (TAEA) template. Both the anti-herpes simplex virus type 1 (anti-HSV-1) activity and cytotoxic activity of synthesized receptor-type derivatives were evaluated in order to find a characteristic structural feature for these bioactivities of compounds. Among the compounds of synthesized symmetrical TAEA-related derivatives, compound 13k showed high anti-HSV-1 activity (50% effective concentration (EC50)=16.7 µM) and low cytotoxicity (50% cytotoxic concentration (CC50)=>200 µM). The presence of a hydrogen bond donor proton in the molecule is thought to be an important structural factor for expressing potential anti-HSV-1 activities.

Interfacial Structure and Proton Conductivity of Nafion at the Pt-Deposited Surface.

Understanding the Nafion-Pt interface structure is important because fuel cell reactions occur at the three-phase boundary. Infrared (IR) p-polarized multiple-angle incidence resolution spectrometry (p-MAIRS) technique was used to investigate the in-plane (IP) and out-of-plane (OP) spectra in the identical substrate. Our previous study revealed that the proton conductivity of the Nafion thin films decreased at the MgO and SiO2 surfaces. We proposed that the origin for the lower proton conductivity can be derived from the highly oriented structure at the interface. However, the interface structure of the Nafion-Pt interface remains unclear. In this study, Nafion thin films were prepared by spin-coating on a Pt-deposited MgO substrates. The IP spectrum exhibited a well-known spectrum, but the OP spectrum was quite differed considerably from the IP spectrum. Furthermore, thickness dependence of the degree of orientation for this OP band was observed at the Nafion-Pt interface. This OP band can be assigned as the vibration mode of the mixture of the CF2 and sulfonic acid groups. At the low-RH region, proton conductivity of the Nafion thin film on the Pt-deposited surface was 1 order of magnitude higher than that on the SiO2 surface. Furthermore, the activation energy was 0.4-0.5 eV, which is lower than that of the SiO2 surface. These results, which suggest that the Pt surface influenced the proton transport property of Nafion thin film, can contribute to understand the relationship between the proton transport property and thin film structure on the Pt-deposited surface at the three-phase boundary for fuel cells.

Modification for Uniform Surface of Nafion Ultrathin Film Deposited by Inkjet Printing.

A lack of knowledge about the features of Nafion confined to ultrathin films at the interface has motivated additional examinations to promote the performance of polymer electrolyte membrane fuel cells (PEMFCs). In this work, we demonstrated the utilization of practical film-forming technique inkjet printing to fabricate a Nafion ultrathin film less than 10 nm thickness. However, the well-known "coffee-ring" effect caused poor quality of the printed pattern, which has restricted its application. This report describes a systematic investigation of necessary parameters such as ink concentration, substrate type, pitch, and offset for printing processes. Furthermore, post-treatment in an ethanol vapor atmosphere exhibited a significant effect on flattening and homogenizing the film surface morphology. Results show that the well-distributed Nafion ultrathin film modified by ethanol vapor annealing manifested much-improved proton conductivity.