Precise Manipulation of Electron Transfers in Clustered Five Redox Sites.

Electron transfers in multinuclear metal complexes are the origin of their unique functionalities both in natural and artificial systems. However, electron transfers in multinuclear metal complexes are generally complicated, and predicting and controlling these electron transfers is extremely difficult. Herein, we report the precise manipulation of the electron transfers in multinuclear metal complexes. The development of a rational synthetic strategy afforded a series of pentanuclear metal complexes which composed of metal ions and 3,5-bis(2-pyridyl)pyrazole (Hbpp) as a platform to probe the phenomena. Electrochemical and spectroscopic investigations clarified overall picture of the electron transfers in the pentanuclear complexes. In addition, unique electron transfer behaviors, in which the reduction of a metal center occurs during the oxidation of the overall complex, were identified. We also elucidated the two dominant factors that determine the manner of the electron transfers. Our results provide comprehensive guidelines for interpreting the complicated electron transfers in multinuclear metal complexes.

Frequency, Characteristics, and Preventability of Adverse Drug Reactions in Perioperative Neurosurgery: Analysis Over 11 Years.

OBJECTIVE: Despite the importance of adverse drug reactions (ADRs), little is known about their role in perioperative neurosurgery. This study aimed to determine the prevalence of ADRs in perioperative neurosurgery and clarify the characteristics, severity, preventability, and risk factors of ADRs. METHODS: Data for all patients who underwent neurosurgical procedures over an 11-year period were analyzed. During the study period, 3648 surgical procedures were performed for 2695 patients. Demographic and clinical information documented included medical history, allergic history, diagnosis, surgical method, suspected drugs, concomitant medications, and drug details. Multivariate logistic regression analyses were performed to identify independent parameters that were correlated with ADRs. RESULTS: In total, 467 ADRs (18.3% ADRs/all neurosurgical procedures) were experienced by 401 patients. Anticonvulsants were associated with the highest number of ADRs (16.0%), followed by antibiotics (14.7%). Patients with ADRs were older than patients without ADRs (P<0.01). The total number of drugs in patients with ADRs was 8.8±3.6, compared to 5.2±2.4 for patients without ADRs (P<0.01). There were no significant differences in sex, allergic history, severe renal dysfunction (eGFR<30 ml/min/1.73 m2), hypertension, diabetes, urgency of surgery, and type of surgery. Multivariate analysis showed that a high total number of drugs (odds=3.2; 95%CI 1.9-5.1) and older age (odds=2.1; 95%CI 1.3-3.8) were independent risk factors for ADRs. CONCLUSIONS: The frequency of suspected and severe ADRs was higher than expected. Polypharmacy and older age were independent risk factors for ADRs in perioperative neurosurgery. To decrease ADRs during perioperative neurosurgery, polypharmacy must be discouraged, especially among older adult patients.

Hemorrhage from metastatic brain epithelioid hemangioendothelioma: A case report.

In this report, we describe a very rare case of metastatic epithelioid hemangio-endothelioma (EHE) originating from other organs such as the lung and requiring craniotomy due to subsequent hemorrhage. A 50-year-old man was diagnosed with EHE in the bilateral lungs, the mediastinum, and the right adrenal gland 8 years earlier. One year earlier, he had developed spinal metastasis. Six months earlier, a screening brain MRI had revealed multiple brain metastases of tumor. He developed subcortical hemorrhage from the tumor in the right parietal lobe and successfully underwent removal of hematoma and tumor. Histopathological examinations revealed EHE. Metastatic EHE is very rare but may be at high risk of intracranial hemorrhage. It is quite important to consider the possibility of brain metastasis and subsequent bleeding when treating patients with EHE.

Pituitary apoplexy in endocrinologically silent adenoma during somatostatin analog administration for pancreatic neuroendocrine tumor: A case report.

A dopamine agonist administered for prolactinoma treatment and pituitary stimulation tests are reported as risk factors for pituitary apoplexy. We report a case of an 82-year-old patient who suffered from pituitary apoplexy in an endocrinologically silent adenoma during lanreotide administration. The patient was diagnosed with a pancreatic neuroendocrine tumor with lymph node metastasis and treated with lanreotide for two years. An endoscopic endonasal transsphenoidal approach was used for tumor and hematoma removal. The specimen showed growth hormone and prolactin positivity and was diagnosed as pit1-lineage plurihormonal adenoma. The tumor also showed positivity for somatostatin receptor 2. Thus, lanreotide treatment is a risk factor for pituitary apoplexy even in silent adenoma.

Subtyping of Group 3/4 medulloblastoma as a potential prognostic biomarker among patients treated with reduced dose of craniospinal irradiation: a Japanese Pediatric Molecular Neuro-Oncology Group study.

BACKGROUND: One of the most significant challenges in patients with medulloblastoma is reducing the dose of craniospinal irradiation (CSI) to minimize neurological sequelae in survivors. Molecular characterization of patients receiving lower than standard dose of CSI therapy is important to facilitate further reduction of treatment burden. METHODS: We conducted DNA methylation analysis using an Illumina Methylation EPIC array to investigate molecular prognostic markers in 38 patients with medulloblastoma who were registered in the Japan Pediatric Molecular Neuro-Oncology Group and treated with reduced-dose CSI. RESULTS: Among the patients, 23 were classified as having a standard-risk and 15 as high-risk according to the classic classification based on tumor resection rate and presence of metastasis, respectively. The median follow-up period was 71.5 months (12.0-231.0). The median CSI dose was 18 Gy (15.0-24.0) in both groups, and 5 patients in the high-risk group received a CSI dose of 18.0 Gy. Molecular subgrouping revealed that the standard-risk cohort included 5 WNT, 2 SHH, and 16 Group 3/4 cases; all 15 patients in the high-risk cohort had Group 3/4 medulloblastoma. Among the patients with Group 3/4 medulloblastoma, 9 of the 31 Group 3/4 cases were subclassified as subclass II, III, and V, which were known to an association with poor prognosis according to the novel subtyping among the subgroups. Patients with poor prognostic subtype showed worse prognosis than that of others (5-year progression survival rate 90.4% vs. 22.2%; p < 0.0001). The result was replicated in the multivariate analysis (hazard ratio12.77, 95% confidence interval for hazard ratio 2.38-99.21, p value 0.0026 for progression-free survival, hazard ratio 5.02, 95% confidence interval for hazard ratio 1.03-29.11, p value 0.044 for overall survival). CONCLUSION: Although these findings require validation in a larger cohort, the present findings suggest that novel subtyping of Group 3/4 medulloblastoma may be a promising prognostic biomarker even among patients treated with lower-dose CSI than standard treatment.

[A Surgical Case of Currarino Syndrome with Syringomyelia].

Currarino syndrome is characterized by a triad of anorectal malformations, sacral defects, and presacral masses. Although it is not extremely rare, this report presents a surgical case of Currarino syndrome with syringomyelia and discusses related literature. The patient is a girl, aged 2 years and 2 months, who presented with marked constipation, chronic cystitis, and lower limb weakness. After examining the patient through magnetic resonance imaging, we diagnosed her with rectal compression due to meningocele and syringomyelia. The base of the meningocele was detached, and the spinal cord was untethered. One week after surgery, her lower limb weakness and constipation improved. Following up on symptoms and performing imaging is essential to determine a treatment plan for Currarino syndrome. (Received 28 February, 2023; Accepted 22 March, 2023; Published 1 August, 2023).

Endoscopic third ventriculostomy for patients with Blake's pouch cyst with adult-onset hydrocephalus: Importance of improved cerebrospinal fluid flow in the prepontine cistern - A case report.

Background: Blake's pouch cyst (BPC) is a posterior fossa cystic malformation that commonly occurs in children with rare adult onset. Herein, we report a case of adult onsets BPC. Case Description: A 61-year-old man presented with gait and cognitive disturbance. Preoperative magnetic resonance imaging (MRI) revealed scarring in the prepontine cistern, and cine phase-contrast MRI revealed no pulsation. Endoscopic third ventriculostomy (ETV) was performed with opening the scarring in the prepontine cistern. Postoperative cine phase-contrast MRI revealed that cerebrospinal fluid (CSF) flow in the prepontine cistern improved, resolving the patient's symptoms. Conclusion: We report a case of adult-onset BPC. The mechanism by which is becomes symptomatic is still unclear. We opened the scar in prepontine cistern in addition to ETV with good results. In this report, we discussed the importance of the improvement in CSF dynamics in the prepontine cistern.

A Catalytic Alkylation of Ketones via sp3 C-H Bond Activation.

We identified a ternary hybrid catalyst system composed of an acridinium photoredox catalyst, a thiophosphoric imide (TPI) catalyst, and a titanium complex catalyst that promoted an intermolecular addition reaction of organic molecules with various ketones through sp3 C-H bond activation. The thiyl radical generated via single-electron oxidation of TPI by the excited photoredox catalyst abstracted a hydrogen atom from organic molecules such as toluene, benzyl alcohol, alkenes, aldehydes, and THF. The thus-generated carbon-centered radical species underwent addition to ketones and aldehydes. This intrinsically unfavorable step was promoted by single-electron reduction of the intermediate alkoxy radical by catalytically generated titanium(III) species. This reaction provided an efficient and straightforward route to a broad range of tertiary alcohols and was successfully applied to late-stage functionalization of drugs or their derivatives. The proposed mechanism was supported by both experimental and theoretical studies.

Acute subdural hematoma in an infant with a biphasic clinical course and late reduced diffusion.

Background: Bright tree appearance (BTA) is a characteristic finding on diffusion-weighted magnetic resonance (MR) imaging with transient high intensity in the white matter. BTA is characteristic of infants with acute encephalopathy with biphasic seizures, but it has also been reported in head trauma cases. In this report, we describe an infant case of traumatic brain injury that demonstrated a biphasic clinical course and late reduced diffusion (TBIRD). Case Description: A 5-month-old boy suffered from head trauma and developed coma and seizures. Computed tomography scans revealed acute subdural hematoma on the right side. He underwent an emergency operation to remove the hematoma but subsequently had seizure clusters for three days. Diffusion-weighted MR imaging revealed BTA in the right cerebral hemisphere. He was treated with antiepileptic agents and fully recovered to pre-injury condition, and MR imaging no further revealed any BTA 20 days after head trauma. He developed no complications at the 10-month postoperative follow-up. Conclusion: We reported a case of TBIRD following head trauma in the infant. The pathogenesis remains unclear, but we consider the possibility of biphasic seizures in infant head trauma cases, and we should appropriately administer the anticonvulsants and carefully check for MR imaging.

[Conventional Cranioplasty for Craniosynostosis].

Conventional cranioplasty is a basic operative procedure for craniosynostosis. This procedure is more invasive, but can be completed in shorter treatment period than distraction osteogenesis. This surgery can allow delicate cranial reshaping, and is indicated in most age groups. The operative procedures may differ depending on the skull shape. During this procedure, complete brain release from the skull compression must be achieved. In most patients, bone flaps float from the dura mater after completion of craniotomy. The bone flap must be reshaped to the ideal form, and should be fixed with absorbable plates instead of titanium plates to avoid plate migration. To close the scalp, the galea should be sutured tight to avoid wound trouble. After the operation, patients should be followed up at an out-patient clinic; the skull and face shape should be checked by a neurosurgeon and plastic surgeon as the treated skull has risk of backslide, and development should be regularly checked by a pediatrician.

Calcifying pseudoneoplasm of the neuraxis (CAPNON) associated with neurenteric cyst. An autopsy case showing unusual fatal outcome.

A 53-year-old man with a history of an untreated brain mass was taken to Toyama Prefectural Central Hospital by emergency transport. Computed tomography revealed an intracranial hypo-attenuated lesion exhibiting mass effect. Several calcified foci were observed around the lesion. His radiographical diagnosis was meningioma with calcification and edema. He suddenly showed tonic seizure after admission; therefore an emergency craniotomy was performed. However, he unfortunately died due to advanced cerebral edema. Microscopic findings of the surgically obtained materials were consistent with neurenteric cyst (NC). Intracranial hard masses were found adjacent to NCs, and the masses were composed of fibrous cartilage-like matrix with extensive linear calcification and the presence of surrounding round-to-oval epithelioid cells. Thus, calcifying pseudoneoplasm of the neuraxis (CAPNON) associated with NC was considered the most appropriate diagnosis of the present case. To the best of our knowledge, this is the first report of such a case. The present case suggests that delay of treatment might cause a poor outcome, at least in CAPNON associated with NC. Careful investigations, including the underlying pathology, may be essential when considering the etiology of CAPNON and its treatment strategies.

Impact of system approach and personal performance on preventable morbidity and mortality events in neurosurgery patients.

PURPOSE: Adverse events in neurosurgery are a serious problem. The approach for seeking solutions for adverse events has shifted from a personal approach to a systemic approach. However, to some extent, preventable morbidity events could be related to personal performance. This study aimed to clarify the impact of personal performance and systematic failure on the occurrence of morbidity and mortality events in neurosurgery patients. METHODS: All morbidity and mortality conference data stored within our department over a 9-year period were analyzed. There were 4580 admitted patients and 3262 surgical procedures performed. We performed a three-step classification of morbidity and mortality events based on the possibility of prevention, root of the event, and personal or systemic issues. RESULTS: As a result of the first step, 214 preventable and 278 unpreventable events were identified. Of the preventable events, two mortality and 212 morbidity events were analyzed. In the second step, 155 (72.4%), 34 (15.9%), 13 (6.1%), and 12 (5.6%) events were categorized as technical complications, critical events, judgment errors, and human factors, respectively. There were 179 events (83.6%) classified as personal performance issues and 35 events (16.4%) as systemic issues. The ratio of personal performance to systemic issues varied widely, with significant differences among the four categories (P < 0.01). CONCLUSIONS: Among neurosurgery patients who have preventable morbidity, issues related to personal performance were more frequent than systemic issues. Efforts to improve systems should be unwavering. However, the personal responsibility of neurosurgeons to avoid preventable complications should not be ignored.

Differentiation of Fibroblasts Into Myofibroblasts in the Arachnoid Membrane of Moyamoya Disease.

BACKGROUND: Moyamoya disease (MMD) is a very specific disorder in terms of spontaneous development of extracranial-to-intracranial collateral circulation through the dura mater, but the underlying mechanisms are unclear. This study aimed to investigate the role of the arachnoid membrane in this unique angiogenesis in MMD. METHODS: A piece of arachnoid membrane and 1- to 2-mL cerebrospinal fluid were simultaneously harvested during surgery from 26 patients with MMD. The specimens were also collected during surgery as the controls from 6 patients with atherosclerotic carotid artery diseases. The arachnoid membrane was subjected to immunohistochemistry and the cerebrospinal fluid was used to measure the concentration of cytokines using ELISA. RESULTS: The number of cells positive for PDGFR (platelet-derived growth factor receptor) α was significantly higher in MMD than in the controls (5.4±3.1 versus 2.3±2.1 cells/field; P=0.02). The results were same in PDGFRß-positive cells (10.1±4.6 versus 4.8±2.8; P=0.01) and α-SMA (alpha-smooth muscle actin)-positive cells (8.8±3.1 versus 2.0±2.5; P<0.01). On multicolor immunofluorescence, 80.5±15.6% of cells positive for PDGFRα in MMD also expressed α-SMA, being significantly higher than 14.6±7.2% in the controls (P<0.01). The density of collagen in the arachnoid membrane was significantly higher in MMD than in the controls (60.3±15.0% versus 40.1±15.3%; P<0.01). In MMD, advanced disease stage was significantly associated with a larger number of α-SMA-positive cells in the arachnoid membrane (P=0.04). On ELISA, the cerebrospinal fluid concentrations of bFGF (basic fibroblast growth factor), HGF (hepatocyte growth factor), and TGF (transforming growth factor)-ß1 were significantly higher in MMD than in the controls. CONCLUSIONS: Based on these findings, MMD may elevate the concentrations of angiogenic factors in the cerebrospinal fluid and then promote the proliferation of fibroblasts in the arachnoid membrane and their differentiation into myofibroblasts, which may, in turn, enhance the production of collagen essential for spontaneous collateral formation across the arachnoid membrane.

Sebaceous adenoma occurring within an intracranial dermoid cyst.

Among intracranial cystic lesions, dermoid cysts and epidermoid cysts are relatively common benign tumors. In a small number of these tumors, it is known that squamous cell carcinomas arise in the lining epithelium of the cysts. Among tumors derived from the appendage, only one case of hidradenoma within a dermoid cyst and no cases of sebaceous tumor have been reported previously. In the present case, a protruding lesion was present in the cystic wall, and it was composed of two cell types: sebaceous cells (sebocytes) and basaloid/germinated cells, being characteristic of this tumor. It is essential to distinguish it from other sebaceous lesions such as hyperplasia, sebaceoma, sebaceous carcinoma, and basal cell carcinoma with sebaceous differentiation derived from the epidermis. The critical distinguishing points in making a differential diagnosis among these lesions are the ratio of the two cell types and the presence or absence of other components such as hair sacs, invasion or cellular atypia. Immunohistochemical examination revealed that the tumor cells were positive for the epithelial markers, such as cytokeratin (CK)14, p63, p40, high-molecular CK, and adipophilin; these findings are peculiar to sebaceous adenoma. Although there have been several similar case reports of sebaceous tumors associated with dermmoid cysts in the ovaries, most of the intracranial lesions were squamous cell carcinomas that developed within the cysts, and there has been no precedent showing an association with a sebaceous tumor. The present report describes the first case of sebaceous adenoma that occurred in an intracranial dermoid cyst.

Photochemical hydrogen production based on the HCOOH/CO2 cycle promoted by a pentanuclear cobalt complex.

The first catalytic cycle for hydrogen production based on the photochemical two-electron reduction of carbon dioxide (CO2) and the dehydrogenation of formic acid at ambient temperature was demonstrated using a pentanuclear cobalt complex (Co5). A series of mechanistic studies were performed to elucidate the mechanism responsible for the promotion of the photocatalytic cycle by Co5.

Long-term Outcomes of Non-syndromic and Syndromic Craniosynostosis: Analysis of Demographic, Morphologic, and Surgical Factors.

In this study, we analyzed the outcomes of patients (followed for 5-38 years, average 17.3 years) with craniosynostosis and evaluated their long-term prognosis. In all, 51 patients who underwent surgery for craniosynostosis between 1982 and 2015, including 12 syndromic and 39 non-syndromic cases, were included. The average age at the initial surgery was significantly lower in the syndromic group than that in the non-syndromic group (9.8 months old vs. 19.9 months, respectively). The surgical procedures did not significantly differ between the two groups, but repeat surgery was significantly more common in the syndromic group than in the non-syndromic group (4 children [30.8%] and 3 children [7.7%], respectively). The children requiring repeat surgery tended to be younger at the initial surgery than those who did not. Those patients who required repeat surgery did not have significantly different surgical procedures initially. The incidence of developmental retardation was 49.0% (43.5% in the non-syndromic group and 66.7% in the syndromic group), and only two children in the non-syndromic group displayed recovery. This study is the first to analyze the prognosis for patients who were followed for at least 5 years after cranioplasty. Repeat surgery was common, especially in syndromic patients. Severity of skull deformity and early initial surgery may be important factors determining the need for repeat surgery. Developmental retardation was also common, and improvement was rare even after surgery.

A case of intestinal perforation with a residual shunt tube placed during childhood: should we remove the non-functioning tube?

We report a 22-year-old man who had abdominal shunt tube migration into colon. He was diagnosed with pilocytic astrocytoma at optic-chiasm to hypothalamus at age of 7, and treated by resection, chemotherapy, and irradiation. He developed hydrocephalus and had multiple ventriculo-peritoneal shunt surgery. At age of 19, he fell in coma due to the subarachnoid and intra-ventricular hemorrhage due to the aneurysm rupture. The ventricle tube was removed, leaving the shunt valve and abdominal tube. The new shunt system was reconstructed at the contralateral side. He was at bed rest after this episode. At age of 20, he had high fever unable to control with antibiotics. The abdominal computed tomogram showed the shunt tube migration in the descending colon. The tube was removed under laparoscopy, and the inflammation was cured. The abandoned peritoneal shunt tube should be removed in patients with high tube migration risks.

Cauda equina schwannoma presenting with subarachnoid and subdural hemorrhage: Its underlying mechanism.

BACKGROUND: A patient presented with a spinal subarachnoid hemorrhage (SAH) and subdural hematoma (SDH) attributed to a spinal schwannoma at the T12-L1 level. CASE DESCRIPTION: A 67-year-old male acutely presented with severe back pain and L1 paraparesis/sensory loss, with urinary incontinence. CT/MR studies showed a spinal SAH and SDH within a likely T12-L1 schwannoma. At surgery, the hemorrhage within the tumor was continuous through the lower pole of the tumor into the subarachnoid and subdural spaces; tumor was dissected away from the surrounding tissues and totally removed. The postoperative course was uneventful, and the preoperative neurological deficits gradually resolved. Histopathologically, the lesion was a schwannoma with intratumoral hemorrhage. CONCLUSION: This case demonstrates the rare acute presentation of a T12-L1 schwannoma with an accompanying intratumoral hemorrhage resulting in both a SDH/SAH.

Dirhodium-Based Supramolecular Framework Catalyst for Visible-Light-Driven Hydrogen Evolution.

The direct conversion of solar energy to clean fuels as alternatives to fossil fuels is an important approach for addressing the global energy shortage and environmental problems. Here, we introduce a new dirhodium-complex-based framework assembly as a heterogeneous molecule-based photocatalyst for hydrogen evolution using visible light. Two dirhodium complexes bearing visible-light-harvesting BODIPY (boron dipyrromethene, BDP) moieties were newly designed and synthesized. The obtained complexes were self-assembled to framework structures (supramolecular framework catalysts), which are stabilized intermolecular noncovalent interactions. These frameworks retained excellent visible-light-harvesting properties of BDP moieties. Investigation of the catalytic performance of the supramolecular framework catalysts revealed that the supramolecular framework catalyst with heavy atoms at BDP moieties exhibited excellent performance in the formation of hydrogen with a reaction rate of 275.8 µmol g-1 h-1 under irradiation of visible light, whereas the supramolecular framework catalyst without heavy atoms at BDP moieties was inactive. Moreover, the system has the additional benefits of high durability (up to 96 h), reusability, and facile removal from the reaction mixture. We also disclosed the effect of heavy atoms at BDP moieties on the catalytic activity and proposed a reaction mechanism.

Cerebrospinal fluid may flow out from the brain through the frontal skull base and choroid plexus: a gold colloid and cadaverine injection study in mouse fetus.

PURPOSE: It has been commonly accepted for a long time that the cerebrospinal fluid (CSF) drains into arachnoid granulations from the subarachnoid space to the dural venous sinus unidirectionally. However, recently, periventricular capillaries and lymphatic concepts have been introduced. The CSF moves along the perivascular space and drains into the capillary vessels or meningeal lymphatic tissues. CSF is involved in removing brain waste out of the brain. In this study, we investigated the outflow mechanism of substances in the CSF from the brain. METHODS: We investigated the movement of CSF by injection of gold colloid conjugates (2, 40, and 200 nm) into the lateral ventricles of mouse fetuses and evaluated the deposition by silver stain with tissue transparency and electron microcopy. Cadaverine was also injected into the lateral ventricle to determine its movement tract. RESULTS: The gold particle deposition was mainly observed in the frontal skull base. Electron microscopic study showed that the gold particle deposition was observed on the choroid plexus and ependyma in the lateral ventricle and also red blood cells in the heart and liver. Two-nanometer particles were exclusively observed in the liver. Cadaverine injection study demonstrated that cadaverine was observed at the extracranial frontal skull base, choroid plexus, ependymal surface, and perivascular area in the brain white matter. CONCLUSION: The particles in the CSF were shown to move from the brain to the frontal skull base and also into the blood stream through the choroid plexus in the fetus. The outflow of particles in the CSF may be regulated by molecular size. This new information will contribute to the prevention of brain degeneration due to brain waste deposition.