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Cerebrovascular malformations comprise abnormal development of cerebral vasculature. They can result in hemorrhagic stroke due to rupture of lesions as well as seizures and neurological defects. The most common forms of cerebrovascular malformations are brain arteriovenous malformations (bAVMs) and cerebral cavernous malformations (CCMs). They occur in both sporadic and inherited forms. Rapidly evolving molecular genetic methodologies have helped to identify causative or associated genes involved in genesis of bAVMs and CCMs. In this review, we highlight the current knowledge regarding the genetic basis of these malformations.

Direct revascularization surgery, such as superficial temporal artery (STA)-middle cerebral artery (MCA) bypass, is effective in preventing ischemia and hemorrhage for moyamoya disease. On the other hand, when ischemia of the anterior cerebral artery (ACA) region progresses after ipsilateral STA-MCA bypass, it is difficult to perform revascularization from the viewpoint of the donor artery. A 55-year-old woman with right hemiparesis was diagnosed with cerebral infarction due to moyamoya disease. Left STA-MCA bypass was performed with no postoperative complications, but memory impairment and decreased motivation were observed 2 months after the operation. Magnetic resonance imaging and angiography revealed new infarction in the bilateral ACA area and deterioration in the signal intensity of bilateral ACAs. Revascularization of the bilateral ACA regions was considered necessary, but the left STA was already used in the previous surgery. Therefore, STA-radial artery (RA)-A3 bypass using RA graft combined with right STA-MCA bypass was performed. STA-A3 bypass using an RA graft may be the optimal treatment for ischemia of the ACA region that progresses after STA-MCA bypass.

Extracranial–intracranial (EC-IC) arterial bypass surgery was developed to prevent subsequent stroke by improving hemodynamics distal to the occluded intracranial artery, but its utilization has been decreasing due to the development in medical treatment. However, EC-IC bypass surgery may be effective for arresting or reversing cognitive decline in patients with cerebral ischemia. A 69-year-old man with the left internal carotid artery occlusion that manifested as scattered cerebral infarction of the left hemisphere presented with dysarthria and transient right hemiparesis. Hemodynamic condition was impaired in the left side, and therefore, EC-IC bypass surgery was performed to prevent recurrence of cerebral infarction. Neuropsychological examination at 6 months after the surgery showed marked improvement as compared to the preoperative examination and there was no recurrence of stroke in the patient. EC-IC bypass may contribute to the improvement of cognitive function as well as the prevention of recurrence of cerebral infarction in patients with hemodynamic insufficiency, but there might be a threshold of hemodynamic impairment with respect to the reversibility of cognitive performance. Investigation of the target and timing can identify cases in which the cognitive function is improved by surgery.

The superficial temporal artery-middle cerebral artery(STA-MCA)bypass technique is extremely important as the basis for both cerebral revascularization in chronic-stage ischemia and emergency surgical revascularization, including open surgical embolectomy. The sophisticated technique of microvascular bypass could also contribute to rescuing inadvertent vascular injuries, such as those occurring in difficult tumor surgery. Therefore, novice neurosurgeons should practice mastering the microvascular suturing technique.

AIM Brain nitric oxide (NO) have been reported in regulation of the sympatho-adrenomedullary system, which can affect voiding and storage functions. Therefore, we investigated effects of intracerebroventricularly (icv) administered 3-(4-morpholinyl)sydnonimine, hydrochloride (SIN-1) (NO donor) on the micturition reflex, focusing on their dependence on the sympatho-adrenomedullary system and on brain N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazole propionate (AMPA) receptors in urethane-anesthetized (0.8 g/kg, ip) male Wistar rats. METHODS Plasma noradrenaline and adrenaline were measured just before and 5 minutes after SIN-1 administration. Evaluation of urodynamic parameters was started 1 hour before SIN-1 administration or intracerebroventricular pretreatment with other drugs. RESULTS SIN-1 (100 and 250 µg/animal) elevated plasma adrenaline and reduced intercontraction interval ([ICI] values; 110.5% [SIN-1, 0 µg] and 54.9% [SIN-1, 250 µg] during 15 minutes after SIN-1 administration [P

The natural history of ruptured basilar artery dissecting aneurysms (BADAs) remains unclear compared to that of ruptured vertebral artery dissecting aneurysms (VADAs). In this study, we investigated the natural history and optimal management of ruptured BADAs. We identified 17 patients with ruptured BADA among 4586 patients with aneurysmal subarachnoid hemorrhage (SAH) treated in seven participating hospitals. A scoping literature review was undertaken to investigate prognostic factors. Six patients among the profiled patients (35.3%) died, all with poor SAH grades (World Federation of Neurological Societies Grade IV and V). Rebleeding after admission was observed in three patients (17.6%) with poor SAH grades. Aggressive treatment and conservative management were initiated in seven and ten patients, respectively. Patients with good SAH grades had significantly higher favorable treatment outcomes than those with poor grades (83.3% vs. 9.1%, P = 0.005). Moreover, based on a scoping review of 158 cases with ruptured BADA, including the patients from our series, approximately 90% of patients with good SAH grades had favorable outcomes. A good SAH grade and no rebleeding after admission were favorable prognostic factors (P 0.0001 and P = 0.002, respectively). The rebleeding rates were 20.2%, 13.3%, and 6.3% for dilated, pearl and string, and stenotic lesions, respectively. We concluded that the natural history of isolated ruptured BADAs may be better than that of VADAs. Although definitive treatment, if possible, is undoubtedly important, conservative management with careful radiological follow-up for morphological changes might be a viable option for patients in good clinical condition and with non-dilated lesions.

Corticotropin-releasing factor (CRF), a representative stress-related neuropeptide, in the central nervous system reportedly both facilitates and suppresses the micturition, therefore, roles of central CRF in regulation of the micturition are still controversial. In this study, we investigated (1) effects of intracerebroventricularly (icv)-administered CRF on the micturition, and (2) brain CRF receptor subtypes (CRFR1/CRFR2) and glutamatergic receptors (NMDA/AMPA subtypes) involved in the CRF-induced effects in male Wistar rats under urethane anesthesia. Intercontraction intervals (ICI), and maximal voiding pressure (MVP), were evaluated by continuous cystometry 45 min before CRF administration or intracerebroventricular pretreatment with other drugs as follows and 3 h after CRF administration. Single-voided volume (Vv), post-voiding residual volume (Rv), bladder capacity (BC), and voiding efficiency (VE) were evaluated by single cystometry 60 min before CRF administration and 60-120 min after the administration. Icv-administered CRF reduced ICI, Vv, and BC without changing MVP, Rv, or VE. The CRF-induced ICI reduction was attenuated by icv-pretreated CP154526 (CRFR1 antagonist), MK-801 (NMDA receptor antagonist), and DNQX (AMPA receptor antagonist), but not by K41498 (CRFR2 antagonist). These results indicate that stimulation of brain CRFR1 can be involved in facilitation of the rat micturition via brain NMDA/AMPA receptors.

The relationship between RNF213 c.14429G > A (p.Arg4810Lys) heterozygous variants and clinical manifestation in patients with Moyamoya disease (MMD) remains unclear. We performed a retrospective cohort analysis to clarify the genotype-phenotype correlation of this RNF213 hotspot variant in MMD patients, especially between wild-type (GG) and heterozygous (GA) genotypes. Clinical and genetic data were obtained from patients diagnosed with MMD in our institutions between October 2011 and November 2020. Clinical data included age, sex, neurological status at diagnosis, medical history, smoking history, alcohol intake, and family history. Of the 225 enrolled patients, 160 (71.1%) were symptomatic, 3 (1.3%) had the homozygous variant, and 149 (66.2%) had the heterozygous variant (GA). Analysis of all enrolled patients showed that the GA group was prone to present bilateral symptoms (p = 0.008) and progressive status (Suzuki grade ≥ 4; p = 0.017). Analysis limited to symptomatic patients revealed that the GA group had bilateral symptoms (p = 0.017), younger age at onset (p = 0.043), and, in particular, a higher proportion of onset before 25 years of age (p = 0.021). Multivariate logistic regression analysis of overall patients revealed that earlier age at diagnosis (p

Background Increasing restrictions over trainees' working hours and the recent coronavirus disease 2019 pandemic warrant new educational methods of surgical skills. We assessed a novel video-recording system for neuroendovascular skill education, developed with the installation of a hybrid operating room (OR) at our institution. Methods A single-plane angiography unit with a large flat display (FlexVision XL; Philips Medical Systems) was installed in our OR. All media sources in the OR, including live fluoroscopy and ceiling-mounted camcorders, were connected to a video switcher. This video switcher laid up to 8 video images into one big image, which was transferred to the large display and the professional-use Blu-ray recorder. The recording was performed continuously during the procedure. This recording system was evaluated retrospectively with a questionnaire administered to the 5 trainees. Results Using this system, 68 interventional procedures were recorded. Among the potential merits, the trainees assigned the greatest value to the simultaneous recording of the operator's hand motions and the fluoroscopy images. Among the potential limitations of the system, the prolonged time and the increased volume of the video data bothered the trainees the most. The recorded video looked like a live demonstration. Conclusions Our “selfie” video recording system was useful for skill training of neuroendovascular interventions.

Moyamoya disease is characterized by severe stenosis at the ends of the bilateral internal carotid arteries and the development of collateral circulation. The disease is very diverse in terms of age at onset, onset patterns, radiological findings, and genetic phenotypes. The pattern of onset is mainly divided into ischemic and hemorrhagic onsets. Recently, the opportunity to identify asymptomatic moyamoya disease, which sometimes manifests as nonspecific symptoms such as headache and dizziness, through screening with magnetic resonance imaging has been increasing. Various recent reports have investigated the associations between the clinical features of different onset patterns of moyamoya disease and the corresponding imaging characteristics. In this article, we have reviewed the natural history, clinical features, and imaging features of each onset pattern of moyamoya disease.

Background: Thoracic ossification of the yellow ligament (OYL) may contribute to myelopathy. In the case presented, the patient additionally had a chronic posterior fossa arachnoid cyst with an acquired Chiari I malformation and cervicothoracic syrinx. Case Description: A 40-year-old female with a posterior fossa arachnoid cyst found 17 years ago, and newly acquired Chiari I malformation (tonsils down 5 mm) with a C7-T5 syrnix, presented with the new onset of lower extremity myelopathy. The MR documented marked dorsolateral cord compression due to T11/T12 OYL. Six months following a laminectomy for resection of OYL, the patient was asymptomatic. Conclusion: In patients presenting with the new onset of lower extremity myelopathy, evaluation of the complete neuraxis may be warranted. Here, the patient has an unchanged posterior fossa arachnoid cyst with an acquired Chiari I malformation/C7-T5 syrinx. However, the patient’s symptoms were fully attributed to the MR-documented T11/T12 OYL that was successfully resected.

The genetic background of intracranial artery stenosis (ICAS), a major cause of ischemic stroke, remains elusive. We performed the world's first genome-wide association study (GWAS) of ICAS using DNA samples from Japanese subjects, to identify the genetic factors associated with ICAS and their correlation with clinical features. We also conducted a phenome-wide association study (PheWAS) of the top variant identified via GWAS to determine its association with systemic disease. The GWAS involved 408 patients with ICAS and 349 healthy controls and utilized an Asian Screening Array of venous blood samples. The PheWAS was performed using genotypic and phenotypic data of the Biobank Japan Project, which contained information on 46 diseases and 60 quantitative trait data from 150,000 Japanese individuals. The GWAS revealed that the East Asian-specific functional variant of RNF213, rs112735431 (c.14429G A, p.Arg4810Lys), was associated with ICAS (odds ratio, 12.3; 95% CI 5.5 to 27.5; P = 7.8 × 10

Brain nicotinic acetylcholine receptors (nAChRs) reportedly suppress the micturition, but the mechanisms responsible for this suppression remain unclear. We previously reported that intracerebroventricularly administered (±)-epibatidine (non-selective nAChR agonist) activated the sympatho-adrenomedullary system, which can affect the micturition. Therefore, we investigated (1) whether intracerebroventricularly administered (±)-epibatidine-induced effects on the micturition were dependent on the sympatho-adrenomedullary system, and (2) brain nAChR subtypes involved in the (±)-epibatidine-induced effects in urethane-anesthetized male Wistar rats. Plasma noradrenaline and adrenaline (catecholamines) were measured just before and 5 min after (±)-epibatidine administration. Evaluation of urodynamic parameters, intercontraction intervals (ICI) and maximal voiding pressure (MVP) by cystometry was started 1 h before (±)-epibatidine administration or intracerebroventricular pretreatment with other drugs and continued 1 h after (±)-epibatidine administration. Intracerebroventricularly administered (±)-epibatidine elevated plasma catecholamines and prolonged ICI without affecting MVP, and these changes were suppressed by intracerebroventricularly pretreated mecamylamine (non-selective nAChR antagonist). Acute bilateral adrenalectomy abolished the (±)-epibatidine-induced elevation of plasma catecholamines, but had no effect on the (±)-epibatidine-induced ICI prolongation. The latter was suppressed by intracerebroventricularly pretreated methyllycaconitine (selective α7-nAChR antagonist), SR95531 (GABAA antagonist), and SCH50911 (GABAB antagonist), but not by dihydro-β-erythroidine (selective α4β2-nAChR antagonist). Intracerebroventricularly administered PHA568487 (selective α7-nAChR agonist) prolonged ICI without affecting MVP, similar to (±)-epibatidine. These results suggest that stimulation of brain α7-nAChRs suppresses the rat micturition through brain GABAA/GABAB receptors, independently of the sympatho-adrenomedullary outflow modulation.

Background: Subarachnoid hemorrhage (SAH) due to rupture of basilar artery dissection (BAD) is extremely rare and often has a poor prognosis. Since ruptured BAD has high rate of rebleeding and mortality, treatment to prevent rerupture is mandatory in the acute phase. However, to date, no optimal treatment has been established which satisfies secure prevention of rerupture and ischemia simultaneously. Herein, we report a case of SAH due to BAD treated with proximal occlusion of basilar artery with superficial temporal artery (STA)-superior cerebellar artery (SCA) bypass, preventing rebleeding securely and ensuring adequate blood flow in the upper basilar region. Case Description: A 48-year-old male presenting with headache and altered mental status was found to have SAH and BAD. To prevent rerupture, proximal occlusion of basilar artery with STA-SCA bypass using anterior transpetrosal approach was performed. The postoperative course was relatively good and there is no evidence of recurrent arterial dissection. Conclusion: Proximal occlusion of the basilar artery combined with STA-SCA bypass was successful in preventing rerupture of BAD and ensuring blood flow in the upper basilar region. Although there is controversy regarding acute treatment for ruptured BAD, direct proximal occlusion with sufficient revascularization using bypass skull base technique may be one of the optimal treatments even in this era of endovascular treatment.

Intracranial artery stenosis (ICAS) is the most common cause of ischemic stroke worldwide. RNF213 single nucleotide variant c.14429G > A (p.Arg4810Lys, rs112735431) was recently reported to be associated with ICAS in East Asians. However, the disease susceptibility of other RNF213 variants has not been clarified. This study comprehensively investigated ICAS-associated RNF213 variants in a pool of 168 Japanese ICAS patients and 1,194 control subjects. We found 138 nonsynonymous germline variants by target resequencing of all coding exons in RNF213. Association study between ICAS patients and control subjects revealed that only p.Arg4810Lys had significant association with ICAS (P = 1.5 × 10–28, odds ratio = 29.3, 95% confidence interval 15.31–56.2 [dominant model]). Fourteen of 138 variants were rare variants detected in ICAS patients not harboring p.Arg4810Lys variant. Two of these rare variants (p.Cys118Arg and p.Leu2356Phe) consistent with variants previously reported in moyamoya disease patients characterized by stenosis of intracranial artery and association with RNF213, and three rare variants (p.Ser193Gly, p.Val1817Leu, and p.Asp3329Tyr) were found neither in control subjects and Single Nucleotide Polymorphism Database. The present findings may improve our understanding of the genetic background of intracranial artery stenosis.

We present a 52-year-old male case of right trigeminal neurinoma at lateral cavernous sinus. The tumor was 40 mm in maximum diameter, obviously compressed temporal lobe and encased internal carotid artery. Extradural middle fossa and transcavernous approach was applied and the tumor was resected via Parkinson's triangle. This approach enabled safe and effective tumor resection, sufficient visualization, and operative field (Figs. 1 and 2). We performed dissection of the tumor from trigeminal nerve, tentorium, and middle fossa and resect the tumor around internal carotid artery sufficiently. Postoperative course was good without any new neurological deficit. This surgical method is considered safe and effective for the resection of the tumor at lateral cavernous sinus.The link to the video can be found at: https://youtu.be/2ekuILIgEuo.

INTRODUCTION AND OBJECTIVE:In the lower urinary tract, nitric oxide (NO) is well known as a relaxation factor in the urethra. On the other hand, in the central nervous system, NO is reported to hav...

OBJECTIVEIn Gamma Knife radiosurgery (GKS) for arteriovenous malformations (AVMs), CT angiography (CTA), MRI, and digital subtraction angiography (DSA) are generally used to define the nidus. Although the AVM angioarchitecture can be visualized with superior resolution using rotational angiography (RA), the efficacy of integrating RA into the GKS treatment planning process has not been elucidated.METHODSUsing data collected from 25 consecutive patients with AVMs who were treated with GKS at the authors’ institution, two neurosurgeons independently created treatment plans for each patient before and after RA integration. For all patients, MR angiography, contrasted T1 imaging, CTA, DSA, and RA were performed before treatment. The prescription isodose volume before (PIVB) and after (PIVA) RA integration was measured. For reference purposes, a reference target volume (RTV) for each nidus was determined by two other physicians independent of the planning surgeons, and the RTV covered by the PIV (RTVPIV) was established. The undertreated volume ratio (UVR), overtreated volume ratio (OVR), and Paddick’s conformal index (CI), which were calculated as RTVPIV/RTV, RTVPIV/PIV, and (RTVPIV)2/(RTV × PIV), respectively, were measured by each neurosurgeon before and after RA integration, and the surgeons’ values at each point were averaged. Wilcoxon signed-rank tests were used to compare the values obtained before and after RA integration. The percentage change from before to after RA integration was calculated for the average UVR (%ΔUVRave), OVR (%ΔOVRave), and CI (%ΔCIave) in each patient, as ([value after RA integration]/[value before RA integration] − 1) × 100. The relationships between prior histories and these percentage change values were examined using Wilcoxon signed-rank tests.RESULTSThe average values obtained by the two surgeons for the median UVR, OVR, and CI were 0.854, 0.445, and 0.367 before RA integration and 0.882, 0.478, and 0.463 after RA integration, respectively. All variables significantly improved after compared with before RA integration (UVR, p = 0.009; OVR, p < 0.001; CI, p < 0.001). Prior hemorrhage was significantly associated with larger %ΔOVRave (median 20.8% vs 7.2%; p = 0.023) and %ΔCIave (median 33.9% vs 13.8%; p = 0.014), but not %ΔUVRave (median 4.7% vs 4.0%; p = 0.449).CONCLUSIONSIntegrating RA into GKS treatment planning may permit better dose planning owing to clearer visualization of the nidus and, as such, may reduce undertreatment and waste irradiation. Further studies examining whether the observed RA-related improvement in dose planning also improves the radiosurgical outcome are needed.

Intracranial aneurysms may cause embolic stroke. Medical or surgical management is selected on an individual basis, as the optimal treatment strategy has not been established. A 79-year-old woman with a large cavernous carotid aneurysm suffered repeated embolic stroke after enlargement and partial thrombosis of the aneurysm, in spite of antiplatelet therapy. Coil embolization of the primitive trigeminal artery and ligation of the internal carotid artery (ICA) at the cervical portion followed by high-flow bypass from the cervical external carotid artery to the middle cerebral artery were performed. The aneurysm was thrombosed, and prevention of further stroke was achieved. Acute enlargement and thrombosis of large or giant cavernous carotid aneurysm may cause repeated embolic stroke, and requires emergent exclusion of the aneurysm from circulation by proximal ICA occlusion together with distal revascularization before devastating embolic stroke occurs.

A novel series of anion conductive polymers, quaternized poly(phenylene alkylene)s (QPAs), were synthesized and characterized. Because of the unique main chain structure composed of alkylene and am...

INTRODUCTION AND OBJECTIVES:Psychological stress exacerbates symptoms of bladder dysfunction. We previously reported that epibatidine (EP), a nicotinic acetylcholine receptor (nAChR) agonist, centr...

Synthesis and properties of a series of ammonium-containing terpolymers (QPAF-3) as anion conductive membranes are reported. The QPAF-3s composed of perfluoroalkylene, alkylene, and ammonium-functionalized phenylene groups without heteroatom linkages in the main chain were synthesized via nickel-mediated polycondensation reaction, followed by chloromethylation, quaternization, and ion exchange reactions. Self-standing, bendable membranes were obtained by solution casting. The QPAF-3 membrane with optimized terpolymer composition and ion exchange capacity (1.46 meq g−1) showed high hydroxide ion conductivity (123 mS cm−1 in water at 80 °C). The alkaline stability test in 1 M KOH for 1000 h at 80 °C and the post-test analysis with IR spectra and tensile strength suggested that ammonium groups were likely to be decomposed while the polymer main chain was chemically more robust. The presence of the alkylene groups in the terpolymers lowered solubility, glass transition temperature, and elongation property of the resulting membranes. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1442–1450

A novel series of ammonium-containing copolymers (QPAF-4) were designed and synthesized as anion exchange membranes for alkaline fuel cell applications. The copolymers were prepared via a nickel promoted polycondensation reaction with high molecular weights (Mw = 72.7–276.4 kDa as precursors) and were composed of perfluoroalkylene and fluorenyl groups with pendant ammonium groups. The QPAF-4 membrane with optimized copolymer composition and ion exchange capacity exhibited high hydroxide ion conductivity (86.2 mS cm−1 in water at 80 °C) and excellent mechanical properties (large elongation at break = 269%). A severe alkaline stability test of the QPAF-4 membranes in 1 M KOH at 80 °C for 1000 h and the post-test analyses of the 1H NMR spectra, solubility, and mechanical properties revealed minor, or no, changes in the chemical structure and properties. Alkaline fuel cells using the QPAF-4 membrane were operated using hydrazine as a fuel and oxygen or air as oxidant to achieve the high maximum power density of 515 mW cm−2. The durability of the membrane was also confirmed in the operating fuel cell at a constant current density for longer than 1000 h.

Background:Intracranial embolism related to cerebral angiography is rare but one of the complications of the procedure. However, the standard management of acute intracranial embolism for this etiology has not been established, and there have been very few reports in the past.Case Description:A 68-year-old male was incidentally found to have an unruptured aneurysm of anterior communicating artery (ACoA). Immediately after the cerebral angiography for the purpose of detailed examination of the aneurysm, the right partial hemiparalysis and mild aphasia developed. Magnetic resonance imaging/angiography (MRI/A) revealed an occlusion in the peripheral part of the left middle cerebral artery (MCA). Due to the existence of magnetic resonance angiography-diffusion mismatch, emergent craniotomy was immediately performed to remove intra-arterial thrombus. We also performed clipping for an unruptured ACoA aneurysm with this approach. Postoperative MRI/A showed that the occluded artery was recanalized and a slight infarction was observed in the left cerebral hemisphere. The patient was discharged on foot and followed at outpatient clinic over 4 years without no neurological deficit.Conclusion:Emergent surgical embolectomy for distal MCA occlusion related to cerebral angiography followed by neck clipping for an unruptured aneurysm of the ACoA was successful in treating acute occlusion of the peripheral part of the MCA in a patient with an unruptured aneurysm. As there are few similar cases, there is controversy about the best management, but this surgical method can be a safe and effective treatment.

Background: Some complications associated with cisternal drainage have been reported; however, there are few reports on direct vascular injury caused by cisternal drain. We experienced two rare cases of thalamic infarction caused by cisternal drain placement during open clipping for a ruptured anterior communicating artery (AcomA) aneurysm through an anterior interhemispheric approach. Case Description: Two cases of ruptured AcomA aneurysm were treated by surgical clipping through an anterior interhemispheric approach, and then a cisternal drain was inserted from opticocarotid space toward prepontine cistern. Postoperatively, the magnetic resonance imaging showed unilateral anterior-medial thalamic infarction in both two cases. By reviewing the postoperative computed tomography and digital subtraction angiography, it was suspected that the cisternal drain, which was inserted slightly deep, obstructed the P1 perforator because of an anatomical variation involving a lowered basilar bifurcation and caused postoperative unilateral paramedian thalamic infarction. Conclusion: To avoid these complications, neurosurgeons should consider the potential for P1 perforator injury related to cisternal drain placement.

We present a 71-year-old female case of left cerebellopontine angle (CPA) meningioma who presented with progressive hearing loss. The tumor was 35 mm in maximum diameter, obviously compressed the brain stem and cerebellum, and also displaced cranial nerves 7th and 8th anteriorly (Fig. 1). Retrosigmoid approach was chosen to resect the tumor aiming for hearing improvement. We performed dissection of the tumor from cranial nerves 7th and 8th gently and resection of the tumor except for the part adhesive to these cranial nerves (Fig. 2). Postoperative course was good without any new neurological deficit. Postoperative examination also showed improvement of high-frequency hearing of the left side, and auditory brainstem response demonstrated wave 2 to 5, which was not identify on preoperative examination. These procedures enabled safe and effective resection of the tumor and contributed to hearing improvement.The link to the video can be found at: https://youtu.be/hkRSCxtV3bY.

Aims To clarify the roles of hydrogen sulfide (H2 S), an endogenous gasotransmitter, in the rat bladder and prostate, we investigated the distribution of enzymes related to H2 S biosynthesis (cystathionine β-synthase [CBS], cystathionine γ-lyase [CSE], 3-mercaptopyruvate sulfurtransferase [MPST], cysteine aminotransferase [CAT], and D-amino acid oxidase [DAO]) and the content of H2 S. We also investigated the effects of H2 S donors (NaHS and GYY4137) on the contractility of both tissues and on micturition. Methods The distribution of these enzymes was investigated by real-time PCR, Western blot, and immunohistochemistry. Tissue H2 S content was measured by the methylene blue method. The effects of NaHS (1 × 10-9 to 3 × 10-4 M) were evaluated on carbachol (10-5 M)-induced pre-contracted bladder strips, and on noradrenaline (10-5 M)-induced pre-contracted prostate strips, which were pretreated with propranolol (10-6 M). In addition, in urethane-anesthetized male Wistar rats, the effects of intravesically instilled GYY4137 (10-8 , 10-7 , and 10-6 M) on micturition were evaluated by cystometry. Results MPST and CAT were detected in the bladder and prostate, CBS was only detected in the prostate, while CSE and DAO were not detected in both tissues. Immunoreactivity of these enzymes was mainly detected in the urothelium and smooth muscle layer of the bladder and in the prostate glandular epithelium. H2 S was detected in both tissues. NaHS dose-dependently induced relaxation of pre-contracted bladder and prostate strips. Intravesically instilled GYY4137 significantly prolonged intercontraction intervals. Conclusions It is possible that H2 S can function as an endogenous relaxation factor in the rat bladder and prostate.

White matter injury is an important cause of functional disability of the brain. We comprehensively analyzed a modified endothelin-1 (ET-1) injection-induced white matter injury model in the rat which is very valuable for investigating the underlying mechanisms of subcortical ischemic stroke. ET-1 was stereotactically injected into the internal capsule of the rat. To avoid complications with leakage of ET-1 into the lateral ventricle, the safest trajectory angle to the target was established. Rats with white matter injury were extensively evaluated for structural changes and functional sequelae, using motor function tests, magnetic resonance (MR) imaging, histopathology evolution, volume estimation of the lesion, and neuroanatomical identification of affected neurons using the retrograde tracer hydroxystilbamidine. Optimization of the trajectory of the ET-1 injection needle provided excellent survival rate. MR imaging visualized the white matter injury 2 days after surgery. Motor function deficit appeared temporarily after the operation. Histological studies confirmed damage of axons and myelin sheaths followed by inflammatory reaction and gliosis similar to lacunar infarction, with lesion volume of less than 1% of the whole brain. Hydroxystilbamidine injected into the lesion revealed wide spatial distribution of the affected neuronal population. Compared with prior ET 1 injection models, this method induced standardized amount of white matter damage and temporary motor function deficit in a reproducible and safe manner. The present model is valuable for studying the pathophysiology of not only ischemia, but a broader set of white matter damage conditions in the lissencephalic brain.

A novel series of ammonium-containing copolymers (QPAFs) were synthesized as anion exchange membranes for alkaline fuel cell applications. The precursor copolymers (Mw = 28.3–90.1 kDa) composed of perfluoroalkylene and phenylene groups were obtained by a nickel promoted polycondensation reaction. Chloromethylation and quaternization reactions of the precursors provided thin and ductile QPAF membranes with ion exchange capacity (IEC) ranging from 0.79 to 1.74 meq g−1. The QPAF membranes exhibited a phase-separated morphology based on the hydrophilic/hydrophobic differences in the main chain structure. The QPAF membrane with an optimized copolymer composition and IEC = 1.26 meq g−1 showed high hydroxide ion conductivity (95.5 mS cm−1 in water at 80 °C), excellent mechanical properties (large elongation at break (218%)), and reasonable alkaline stability at 80 °C. An alkaline fuel cell using the QPAF as the membrane and electrode binder achieved the maximum power density of 139 mW cm−2 at a current density of 420 mA cm−2.