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Little is known about the real-world status of neurosurgical treatment of myelomeningocele patients.To investigate the real-world status of neurosurgical treatment of myelomeningocele patients, medical claims data provided by the Japan Medical Data Center (JMDC) were analyzed.The health claims data of 556 patients with myelomeningoceles from January 2005 to March 2020 were examined. The number of neurosurgical procedures, including myelomeningocele repair, tethered cord release, cerebrospinal fluid (CSF) shunt, CSF drainage, and endoscopic third ventriculostomy (ETV), was determined.A total of 313 neurosurgical procedures were performed for 135 patients in 74 institutions during the study period. The shunt survival rate was most affected by shunts that were revised when the patient was less than 1 year old, which had a significantly lower survival rate than all of the initial shunts performed when the patient was less than on1 year old; the 1-year shunt survival rate was 35 vs 64% (P = 0.0102). The survival rate was significantly lower in patients younger than 1 year who had CSF drainage before shunting compared to those younger than 1 year who did not have CSF drainage before shunting; the 1-year shunt survival rate was 27 vs 59% (P = 0.0196), and 81% of patients remained free of tethered cord release 10 years later.In this study, a revised shunt of less than 1 year of age and CSF drainage before shunting were the factors that lowered the shunt survival rate in the real world for CSF shunts for hydrocephalus associated with myelomeningocele.

Background In order to remove a foreign body in the ventricle, such as a ventricular drainage catheter, craniotomy and corticotomy are required to access the ventricle. A case in which a catheter in the 4th ventricle was safely removed with a flexible neuroendoscope is reported. Case description A 47-year-old man underwent coil embolization and ventricular drainage for subarachnoid hemorrhage. 10 days after the operation, he tore off the ventricular drainage catheter and the catheter remained intracranially. The tip of the catheter was in the 4th ventricle and the operation to remove remaining catheter with a neuroendoscope was performed. Using a neuroendoscope, we could remove the catheter safely and did not detect the complications. Conclusion To date, there have been no reports of cases in which a drainage catheter in the ventricle was removed using a flexible endoscope. This case suggests that a flexible endoscope is useful for removing a foreign body from the ventricle less invasively.

The authors present the case of a 1-month-old girl with a lumbosacral lipoma who then developed an extracanalicular syrinx and experienced rapid deterioration. The patient’s initial MRI study, obtained before she became symptomatic, revealed a spinal lipoma with a syrinx in contact with the lipoma-cord interface. She was initially asymptomatic but developed loss of motor function in the left leg 14 days after MRI. Emergency surgery was performed. Intraoperative findings revealed a swollen spinal cord. Lipomatous tissue on the caudal side of the conus was removed subtotally, and the central canal was opened. Expansion of the syrinx was observed intraoperatively. Postoperatively, the patient’s left leg paresis remained. Postoperative MRI revealed rostral and extracanalicular expansion of the syrinx. This is the first report on the rapid deterioration of a conus lipoma due to extracanalicular expansion of a syrinx. Careful follow-up and repeat MRI should be considered for patients with spinal lipomas with syringomyelia, especially when the syrinx is attached to the lipoma-cord interface.

Lipoma of the filum terminale (FL) is an abnormality in which fat is deposited in the filum terminale. This lipoma is often detected by skin abnormalities in the lumbosacral area such as a sacrococcygeal dimple. Some cases may develop tethered cord and become symptomatic. However, the genetic basis of FL is still unclear. This study aimed to determine whether there was a family history of FL or other forms of spina bifida among 54 families of 56 patients with FL and to examine whether there is a familial predisposition in FL. In addition, sex, age at diagnosis, presence of symptoms, presence of sacrococcygeal dimple, and the level of conus medullaris between familial and spontaneous cases were evaluated. Of the 54 families of FL patients, there were 48 siblings. Among the 48 siblings, 2 had “occult” FL. The frequency of FL among siblings was estimated to be 4.2% (2/48), which was significantly higher than the sum of previously reported cases of spontaneous FL (0.91%; p = 0.017). However, there was no significant difference in sex, age at diagnosis, presence of symptoms, presence of sacrococcygeal dimple, diameter of filum terminale, or level of conus medullaris between familial and spontaneous cases. To our knowledge, this is the first report on familial FL and examination of the frequency of FL among siblings. The high probability of FL among siblings of FL patients suggests that genetic factors may play a role in FL development.

Background: A giant prolactinoma extending to the suprasellar area and causing hydrocephalus may be life-threatening and should be treated promptly. A case of a giant prolactinoma with acute hydrocephalus that underwent transventricular neuroendoscopic tumor resection followed by cabergoline administration is presented. Case Description: A 21-year-old man had a headache lasting for about a month. He gradually developed nausea and disturbance of consciousness. Magnetic resonance imaging showed a contrast-enhanced lesion that extended from the intrasellar space to the suprasellar space and into the third ventricle. The tumor obstructed the foramen of Monro and caused hydrocephalus. A blood test showed marked elevation of prolactin (16,790 ng/mL). The tumor was diagnosed as a prolactinoma. The tumor in the third ventricle had formed a cyst, and the cyst wall blocked the right foramen of Monro. The cystic component of the tumor was resected using an Olympus VEF-V flexible neuroendoscope. The histological diagnosis was pituitary adenoma. The hydrocephalus improved rapidly and his consciousness became clear. After the operation, he was started on cabergoline. The tumor size subsequently decreased. Conclusion: Prompt partial resection of the giant prolactinoma by transventricular neuroendoscopy resulted in early improvement of hydrocephalus with less invasiveness, allowing subsequent treatment with cabergoline.

OBJECTIVE Patients with myelomeningocele often require multiple surgeries, but no study has clarified the kind of treatment given to these patients throughout their lives. The authors analyzed the type of surgery that was performed and at what age for Japanese patients with myelomeningoceles. METHODS The Japanese health claims data of 556 patients with myelomeningocele for the period from January 2005 to March 2020 provided by the Japan Medical Data Center Co., Ltd., were examined to investigate the number of surgeries performed and the patient age at surgery for each specialty. The patients were divided into two groups (those ≤ 18 years old [group A] and those > 18 years old [group B]), and the way in which the types of surgery and the percentage of surgeries changed between these two groups was examined. RESULTS The mean follow-up period was 4.4 years. The mean age at the end of the overall follow-up was 18.6 years (range 0–70.5 years), and 1033 surgeries were performed on 294 patients (0.42 surgeries performed per patient per year) during this period. The number of surgeries for patients in group A was 818 in 192 patients, with 0.62 surgeries per patient per year, and for patients in group B it was 215 in 102 patients, with 0.19 surgeries per patient per year. The number of surgeries and the mean age at the time of surgery were as follows: 313 neurosurgeries, 5.16 years; 280 orthopedic surgeries, 11.36 years; 70 urological surgeries, 14.57 years; and 202 dermatological/plastic surgeries, 16.19 years. In the surgeries related to myelomeningocele, the rates of CSF shunt placement, tethered cord release, muscle and tendon surgery, and other bone and joint surgery decreased significantly in group B, but they continued to undergo these surgeries. In group B, the rates of skin surgery, nephrostomy, ureterostomy, and cystostomy were significantly higher. CONCLUSIONS A significant number of surgeries in multiple specialties related to myelomeningocele continue to be performed in adulthood, indicating that these patients require continuous care throughout their lives.

In the treatment of PCNSL, chemotherapy is becoming the main treatment, in a while, radiation therapy is becoming to be avoided. In our hospital, hematology leads an initiative to the treatment of PCNSL from 2021. During the 7 years from 2016, there were 32 cases of PCNSL that underwent initial treatment at our hospital, of which 8 cases occurred after 2021. The breakdown was 6:2 male to female, and the average age was 71.3 years. In 5 relatively young patients, remission was induced with 5 to 6 courses of R-MPV therapy, 3 of which received high-dose chemotherapy combined with autologous peripheral blood stem cell transfusion, all of whom avoided RT and have maintained remission. In 3 older patients, only RT was performed in 1 and HD-MTX therapy was performed in 2, of which RT was combined in 1 and BSC was introduced due to treatment related sepsis in another patient. Although the follow-up period was short, there has been no recurrence except for one patient who became BSC. On the other hand, in 24 patients before 2020, HD-MTX therapy combined with RT was performed in all patients, except for 1 patient who underwent RT only due to advanced age and 1 patient who died before treatment due to poor general condition. Recurrence was observed in 8 cases, and additional RT and chemotherapy were performed. Although no recurrence was seen in 16 cases, there are only 4 patients who had been still followed up, 6 died, and 6 had unknown or BSC, with a poor prognosis. One of the reasons was thought to be related to the decrease in ADL due to radiation injury. In the absence of recurrence, ADL may be maintained long-term in young patients. On the other hand, elderly people cannot avoid RT, which is still a problem.

Background We describe a continuous monitoring method aimed at preserving nerve function during biopsy of lesions on the oculomotor nerve using stimulation of the oculomotor nerve proximal to the lesion. Case Description A 5-year-old girl with a recurrent left oculomotor nerve palsy and contrast-enhancing left oculomotor nerve mass on magnetic resonance imaging underwent a biopsy of the lesion to aid in its diagnosis. At the time of surgery, needle electrodes were inserted into the superior and inferior rectus muscles percutaneously, and cotton-covered electrodes were implanted into the oculomotor nerve proximal to the lesion. Compound muscle action potentials of the oculomotor nerve were measured continuously by monopolar stimulation. The lesion was mapped by direct stimulation, and the unresponsive area was excised. The amplitude of the compound muscle action potentials decreased during the resection but recovered postoperatively. After resection of the lesion, the compound muscle action potentials remained the same as they were preoperatively. No obvious postoperative oculomotor nerve palsy was observed. Conclusions This method of continuous monitoring of the function of the oculomotor nerve is simple to use and is suitable for lesions in close proximity to the oculomotor nerve.

Background: Primary central nervous system lymphoma (PCNSL) originating in the brainstem is uncommon. In particular, PCNSL confined to the tectal plate in adults has never been reported in the past. The case of a 53-year-old man who was diagnosed with PCNSL in the tectal plate is reported. Case Description: The patient was referred to our hospital with a 1-month history of disorientation and magnetic resonance imaging showed hydrocephalus with an enhancing lesion in the tectum. Preoperative blood tests showed a high serum soluble interleukin-2 receptor level of 624 U/ml. Through a single burr hole, endoscopic third ventriculostomy and biopsy of the lesion were simultaneously performed with a flexible endoscope. The histological examination confirmed diffuse large B-cell lymphoma. The patient underwent chemotherapy and radiotherapy. Conclusion: Malignant lymphoma of the tectum may occur in adults. By measuring the soluble interleukin-2 level preoperatively, it was possible to include malignant lymphoma in the differential diagnosis. In addition, the use of a neuroendoscope permits biopsy and hydrocephalus treatment to be performed simultaneously.

Background:In recent years, the efficacy of 5-aminolevulinic acid photodynamic diagnosis (5-ALA PDD) has been reported for various types of brain tumors, including malignant glioma. In addition, many reports have been published on the usefulness of neuroendoscopic surgery for intraventricular lesions. However, no systematic report is available on the combined use of 5-ALA PDD and neuroendoscopy for various intraventricular tumors.Methods:We report 17 consecutive patients with intraventricular tumors. All patients received oral 5-ALA preoperatively and underwent endoscopic surgical treatment (resection or biopsy). We use a rigid endoscope with a built-in PDD system for intraoperative observation.Results:Seven resections and 10 biopsies were performed. Histopathological diagnosis was confirmed in all 17 cases. Gross total resection was achieved in six of seven cases. The fluorescence positivity rates for each tumor were glioblastoma 100% (2/2), low-grade glioma 67% (2/3), subependymoma 0% (0/1), medulloblastoma 100% (1/1), pineoblastoma 0% (0/1), germ cell tumor 75% (3/4), diffuse large B-cell lymphoma 33% (1/3), and metastatic tumor 100% (2/2).Conclusion:Our method has the potential to improve detection of residual tumors in blind spots and deep areas, as well as the accuracy and safety of biopsy procedures for intraventricular lesions that are difficult to view and treat under a microscope.

5-Aminolevulinic acid (5-ALA) fluorescence-guided surgery is widely used for detection and planning of resection of malignant gliomas and other brain tumors. However, no reports have described 5-ALA fluorescence-guided surgery or direct visualization of germ cell tumors. Here, we report two cases of germ cell tumors in which a positive 5-ALA fluorescent signal was visualized with a neuroendoscope. Both cases had a tumor in the pineal region that was associated with hydrocephalus. The patients underwent surgery after administration of 5-ALA. After ventricular puncture of the anterior horn, we could observe the ventricular wall and tumor using the Karl Storz Photodynamic diagnosis system endoscope. Then, biopsy of the pineal tumor and endoscopic third ventriculostomy were performed in both cases. In case 1, a 22-year-old man, part of the ventricular wall and tumor tissue showed red fluorescence. In case 2, a 16-year-old man, part of the fornix and infundibular recess showed red fluorescence, and the tumor showed relatively weak red fluorescence. The histopathological diagnosis of both cases was pure germinoma. This is the first report of direct visualization of mixed germinomas with 5-ALA fluorescence-guided endoscopic surgery. This method not only allows visualization of the tumor mass, but may also be useful for detailed observation in the ventricular wall.

Backgrounds: Delayed cerebral ischemia (DCI) is a major determinant of prognosis in patients with subarachnoid hemorrhage (SAH). However, little is known about the role of microRNAs (miRNAs) in the development of DCI after SAH. We investigated the expression profile of miRNAs and the chronological changes in the expression of microRNA-15a (miR-15a) in the plasma and cerebrospinal fluid (CSF) of SAH patients. Methods: Peripheral blood and CSF samples were collected from eight aneurysmal SAH patients and three controls without SAH. Exosomal miRNAs were isolated and subjected to microarray analysis with the 3D-gene miRNA microarray kit. The time course of the expression of miR-15a was analyzed using quantitative real-time PCR. Then, blood sample collected at day 1 and 5 from 17 SAH patients with DCI and 15 without DCI were analyzed using quantitative real-time PCR. Results: Microarray analysis demonstrated that 12 miRNAs including miR-15a were up- or down-regulated both in the CSF and plasma after SAH within three days. Quantitative real-time PCR revealed that miR-15a expression was significantly increased in both the CSF and plasma, with a peak around 3 to 5 days after SAH. Furthermore, the plasma level of miR-15a in patients with DCI was significantly elevated on day 5, while it remained unchanged in those without DCI. Conclusions: Our results suggest that an early increase in miR-15a may contribute to development of DCI after SAH.

Intraoperative 5-ALA fluorescence diagnosis (PDD) has been shown to improve tumor resection rates in surgery for malignant glioma. Recently, the usefulness of PDD has been reported in tumors other than malignant glioma. However, the fluorescence of intraventricular tumors is not easy to observe under the microscope, because excitation light could not reach enough to the deepest part of the brain. Therefore, we performed endoscopic 5-ALA fluorescence diagnosis of intraventricular tumors and evaluated its usefulness. Ten cases of intraventricular tumors were included in the study. There were 3 germ cell tumors, 2 metastatic brain tumors, 2 pilocytic astrocytomas, 1 malignant lymphoma, 1 subependymoma, and 1 medulloblastoma (recurrent). The tumors were located in the third ventricle in four cases, the lateral ventricle in three cases, the lateral ventricle and the third ventricle in two cases, and the aqueduct in one case. Tumor removal was performed in 6 cases and tumor biopsy in 4 cases. Intraoperative fluorescence could be observed in eight cases: three germ cell tumors, two metastatic brain tumors, two pilocytic astrocytomas, and one malignant lymphoma. Subependymoma and medulloblastoma did not show fluorescence. Among the cases with confirmed fluorescence, the fluorescent sites were targeted for biopsies for germ cell tumors and malignant lymphomas. For metastatic brain tumors and pilocytic astrocytomas, the extent of removal was determined at the time of removal, and the presence of residual tumor was confirmed by fluorescence after removal. Endoscopic 5-ALA fluorescence diagnosis for intraventricular tumors was useful in determining the target of biopsy or the extent of excision and in assessing residual tumors.

Rathke’s cleft cyst is a cystic disease that occurs in the sella turcica or, occasionally, in the suprasellar area. An ectopic Rathke’s cleft cyst is extremely rare, and its nature is less well understood. The authors report the case of a 14-year-old girl who presented with a growing cystic lesion in the prepontine cistern, immediately behind the dorsum sellae. Preoperative imaging and intraoperative investigation showed part of the cyst wall continuing into the dorsum sellae, to the pituitary gland. The cisternal portion of the cyst wall was totally resected via a right subtemporal approach. Histopathological examination of the cyst wall showed a monolayer of ciliated cells, identical to those of Rathke’s cleft cyst. To the best of the authors’ knowledge, this represents the first pediatric case of Rathke’s cleft cyst occurring in the prepontine cistern.

Higher-order genomic architecture varies according to cell type and changes dramatically during differentiation. One of the remarkable examples of spatial genomic reorganization is the rod photoreceptor cell differentiation in nocturnal mammals. The inverted nuclear architecture found in adult mouse rod cells is formed through the reorganization of the conventional architecture during terminal differentiation. However, the mechanisms underlying these changes remain largely unknown. Here, we found that the dynamic deformation of nuclei via actomyosin-mediated contractility contributes to chromocenter clustering and promotes genomic architecture reorganization during differentiation by conducting an in cellulo experiment coupled with phase-field modeling. Similar patterns of dynamic deformation of the nucleus and a concomitant migration of the nuclear content were also observed in rod cells derived from the developing mouse retina. These results indicate that the common phenomenon of dynamic nuclear deformation, which accompanies dynamic cell behavior, can be a universal mechanism for spatiotemporal genomic reorganization., Author summary The motion and spatial reorganization of sub-nuclear domains have been extensively studied using microscopy, but the underlying mechanisms that promote the reorganization are still poorly understood. We found that dynamic nuclear deformation provides a driving force for long-range migration and aggressive clustering of chromocenters, which ultimately induces nuclear architecture reorganization. This study significantly contributes to an improved understanding of the role of nuclear deformation and reorganization of nuclear architecture that seems complex but is based on simple physical properties of the cell.

The purpose of this study was to identify the risk factors and subjective symptoms of drug-induced renal damage.Through a search of the CARPIS (Case Reports of Adverse Drug Reactions and Poisoning Information System) database,which contains over 47,000 case reports of adverse drug reactions,we obtained 476 cases of drug-induced renal damage which were assigned to a case group.We also selected 1,420 non-renal adverse reactions at random and assigned them to a control group.Logistic regression analysis revealed that the patient background factors of child (age : 0-15 years) (odds ratio (OR)=1.92 ; 95% confidence interval (95% C.I.)=1.35-2.71),infection (OR=1.49 ; 95% C.I.=1.06-2.07)and renal damage (OR=2.80 ; 95% C.I.=1.70-4.54)were associated with a significantly greater risk of developing drug-induced renal damage.In addition,bucillamine (OR=18.39 ; 95% C.I.=7.89-48.47),propylthiouracil (OR=9.36 ; 95% C.I.=3.7025.42),penicillamine (OR=7.14 ; 95% C.I.=3.06-17.20)and diclofenac (OR=6.07 ; 95% C.I.=2.72-13.76),and cisplatin (OR=9.69 ; 95% C.I.=4.40-22.03)were found to significantly raise the risk of drug-induced renal damage.Edema,hematuria and oliguria were also significantly associated with drug-induced renal damage.These results will be useful in the community pharmacy setting.

The mechanical properties of Ti–4.5Al–3V–2Mo–2Fe, a relatively low cost titanium alloy originally designed for structural applications (especially for aerospace applications), were investigated. The alloy was subjected to heat treatments with various solution treatment temperatures (annealing temperature) and cooling rates. The mechanical properties of the heat-treated alloys were then used in order to judge the prospects of practical usage of the alloy for healthcare equipment such as wheelchairs. The mechanical properties of Ti–4.5Al–3V–2Mo–2Fe are highly affected by either solution treatment or cooling rate, and they change as a result of the change in the microstructure. The alloy single annealed at temperature in the α + β field has very high fatigue ratio (0.80–0.85) and high specific strength (210–260 MPa/g cm− 3) with a modest fracture toughness (JIC = 25–35 kN/m). This balance of fatigue ratio and specific strength is better than that of the existing wheelchair materials. Thus, from the point of view of mechanical properties, Ti–4.5Al–3V–2Mo–2Fe has high potential to be used for healthcare applications.

BACKGROUND: We are undertaking dendritic cell (DC) therapy against glioma stem-like cells (GSCs) with concomitant maintenance chemotherapy using temozolomide (TMZ). In general, anti-cancer agents are known to suppress immune response in patients. TMZ also suppresses immunity by inducing lymphopenia and myelosuppression in malignant glioma patients. However, there has been no study about the effect of TMZ on DC function. In this study, we evaluate whether concomitant TMZ affects DC function in vitro. METHODS: We isolated human blood plasmacytoid DCs (pDCs) and myelocytoid DCs (mDCs) from healthy volunteers by flow cytometry. These DC subsets were cultured in flat-bottomed 96-well plates at 5 × 104 cells in the final 200 µl of medium per well for 24 h. In the first set of experiment, we assessed cytotoxic activity of TMZ on DCs at clinically relevant concentration. After 24 h, viable cells were measured by a trypan-blue exclusion test. We next measured the Toll-like receptor ligand (TLRL) -induced cytokine production by DCs in the presence of TMZ. DC subsets were stained with FITC-labeled anti-CD83 and PE-labeled anti-CD86 antibody and then analyzed by FACS calibur. We also measured secreted IL-12p40 and IFN-alpha concentration in the supernatant of the cultures by ELISA. RESULTS: Analysis of trypan-blue exclusion of the dead cells showed that over 300 microM of TMZ started to kill both DC subsets and there was no cytocidal effect at 100 microM, a clinically relevant concentration. Therefore, we thereafter used 10 microM to 300 microM for the following assays. We found that TMZ did not affect IFN-alpha production by pDCs and IL-12 production by mDCs in response to various TLRLs. In addition, up to 100 microM of concentration, TMZ did not influence the CD83 and CD86 expression on both DC subsets. CONCLUSIONS: Temozolomide did not significantly affect on DC function, suggesting that DC therapy and concomitant chemotherapy using TMZ may be possible, although further assessment in the clinical setting is necessary. In the presentation, we also would like to present preliminary data on interaction between DCs and two types of GSCs (proneural and mesenchymal). SECONDARY CATEGORY: n/a.

A 23-year-old Japanese woman presented with a newly developed spinal extradural arteriovenous fistula (AVF) during pregnancy. She had been followed up for a suspected spinal cavernous angioma and became unable to walk during the 29th week of her pregnancy. Magnetic resonance (MR) imaging showed a spinal extradural AVF at the T3 to T4 levels compressing the spinal cord. After delivery by cesarean section, her neurological symptoms gradually began to resolve, and she was able to resume walking without assistance. MR imaging confirmed spontaneous regression of the AVF. This case suggests that exacerbated neurological symptoms and AVF growth triggered by pregnancy can improve after delivery without interventional treatment. Careful follow up of neurological findings is required to prevent unnecessary interventional procedures in pregnant women with spinal AVF.

A 23-year-old Japanese woman presented with a newly developed spinal extradural arteriovenous fistula (AVF) during pregnancy. She had been followed up for a suspected spinal cavernous angioma and became unable to walk during the 29th week of her pregnancy. Magnetic resonance (MR) imaging showed a spinal extradural AVF at the T3 to T4 levels compressing the spinal cord. After delivery by cesarean section, her neurological symptoms gradually began to resolve, and she was able to resume walking without assistance. MR imaging confirmed spontaneous regression of the AVF. This case suggests that exacerbated neurological symptoms and AVF growth triggered by pregnancy can improve after delivery without interventional treatment. Careful follow up of neurological findings is required to prevent unnecessary interventional procedures in pregnant women with spinal AVF.

Since the healing capacity of articular cartilage is limited, it is important to develop cell-based therapies for the repair of cartilage. Although synthetic or animal-derived scaffolds are frequently used for effective cell delivery long-term safety and efficiency of such scaffolds still remain unclear. We have been developing a new tissue engineering technique for cartilage repair using a scaffold-free tissue engineered construct (TEC) bio-synthesized from synovium-derived mesenchymal stem cells (MSCs) [1]. As the TEC specimen is composed of cells with their native extracellular matrix, we believe that it is free from concern regarding long term immunological effects. Fujie et al. found in a micro indentation test using an atomic force microscope (AFM) that the immature porcine cartilage-like tissue repaired with TEC exhibited lower stiffness as compared with normal cartilage in immature porcine femur [2], although the macro-scale stiffness of the repaired tissue was almost same as that of the normal cartilage [3]. In the present study, we investigated the macro and micro-compressive properties of mature porcine cartilage-like tissue repaired with TEC.

Highly doped Si needles are grown on a low doped Si substrate that has an opposite polarity to the needles via a sulfur-assisted process using Au catalyst particles. By using a micromanipulator system in a scanning electron microscope, individual needles are probed, and current–voltage curves are measured. The curves clearly show rectification.

The polymerization of terephthalaldehyde and hexamethylenediamine to obtain a film-forming high molecular weight polyimine solution was considerably facilitated through the use of m-cresol as a solvent under mild conditions. The reaction was reversible, though the equilibrium favored a high product concentration. A crystalline but partially cross-linked powder and film were obtained from the solution.

Condensation of 2, 2-bis[4-(4-aminophenoxy)phenyl]propane and terephthalaldehyde in dilute solution was found to give a highly crystalline powder in 5-90% yield. The product had remarkable similarities to the linear polymer having the same repeating unit. But its nonmacromolecular character was elucidated by gel permeation chromatogram and field desorption mass analyses. A dimeric ring structure is proposed.

Bis-β-isocyanatoethyl disulfide (BIED) was synthesized from diethyl dithiodipropionate and its reaction with cotton in dimethylformamide was investigated. The sulfur content of the treated cotton decreased by reduction with tri-n-butylphosphine. The polarographic and infrared analyses revealed that BIED reacted with cotton both monofunctionally and bifunctionally to form branches and crosslinks, respectively. The ratio of the crosslinks to the total amount of BIED combined increased in general as the reaction progressed. X-Ray study indicated that the reaction took place mainly in the original amorphous region.

The oxidation behavior of mercaptocellulose prepared from tosylated cotton and of cellulose β-mercaptoethylaminocarboxylate (RDTC), which was prepared by reduction of a cotton derivative made by the reaction with bis-β-isocyanatoethyl disulfide, was studied, and the factors controlling the oxidation behaviors of solid polymeric mercaptans were discussed. RDTC was converted quantitatively to the corresponding disulfide by oxidation under mild conditions. Repeated oxidation–reduction cycles were applied to RDTC to demonstrate complete reversibility of disulfide crosslinking. On the other hand, only a portion of the mercaptan in mercaptocellulose could form disulfide by oxidation. It is considered that the mobility of the mercapto groups necessary for the oxidation coupling is restricted because they are attached directly to rigid cellulose chains. The oxidation of RDTC with air in alkaline medium was studied kinetically. It was found that the oxidation of the mercaptan in paired placement in the cellulose matrix proceeded more than ten times faster than that of the randomly placed mercaptan.

Seit langem nimmt man im allgemeinen an, class Carnosin (β-Alanylhistidin) und seine Methylverbindungen, Anserin (β-Alanyl-l-N-methylhistidin) und Ophidin (β-Alanyl-2-C-methylhistidin), nur in den Muskelextrakten der Wirbeltiere als charakteristische Substanzen enthalten sind (1-3). Die interessanten Ergebnisse uber die Verteilung dieser Dipeptide und ihren Gehalt (4-6) in Muskeln der verschiedenen Tiere wurden schon gewonnen, wahrend vieles ihrer physiologischen und pharmakologischen Wirkungen (7-10) jedoch noch unbekannt bleibt. Es ist vor allem sehr interessant, dass Ophidin, welches bis jetzt nur aus den Schlangenmuskeln (3, 11-13) abgetrennt wurde, auch aus anderen Geweben ausser Muskeln isoliert wurde. Neulich trennten Tsunoo und andere weisse, nadelformige Kristalle aus gefrorenem Walpankreas (14) und Walmuskel (15) ab, welche aus der Elementaranalyse nach den Salzbildungen, Spaltungsversuchen durch HBr und IR-Spektrum von ihren Pikrolonaten als Ophidin identifiziert wurden. Aus den oben erwahnten Tatsachen seien eingehende Untersuchungen uber Verteilung dieser Dipeptide und ihren Gehalt in Muskel und in anderen Geweben der verschiedenen Tierarten ein wertvoller Helfer, um ihre physiologischen und pharmakologischen Wirkungen zur Klarheit zu kommen. In vorliegenden versuchen haben wir das Vorkommen dieser Dipeptide in der Muskulatur der Giftschlange “Habu” und ihre pharmakologischen Wirkungen untersucht.

Condensation of 2, 2-bis[4-(4-aminophenoxy)phenyl]propane and terephthalaldehyde in dilute solution was found to give a highly crystalline powder in 5-90% yield. The product had remarkable similarities to the linear polymer having the same repeating unit. But its nonmacromolecular character was elucidated by gel permeation chromatogram and field desorption mass analyses. A dimeric ring structure is proposed.