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Ependymomas encompass multiple, clinically relevant tumor types based on localization, genetic alterations, and epigenetic and transcriptomic profiles. Tumors belonging to the methylation class of spinal ependymoma (SP-EPN) represent the most common intramedullary neoplasms in children and adults. However, molecular data of SP-EPN are scarce, and clear treatment recommendations are lacking. The only known recurrent genetic events in SP-EPN are loss of chromosome 22q and NF2 mutations. Yet, it remains unclear whether SP-EPN with germline or sporadic NF2 mutations or with NF2 wild type status differ clinically or molecularly. To provide a comprehensive molecular profile of SP-EPN, we integrated epigenetic, genomic, transcriptomic, and histological analyses of up to 237 cases. Clustering of methylation data revealed two distinct molecular SP-EPN subtypes. The distribution of NF2 mutated cases differed significantly across these subtypes (p

The geometries (i.e., dip angles) of active faults from the surface to the seismogenic zone are among the most important factors used to evaluate earthquake ground motion, which is crucial to seismic hazard assessments in urban areas. In Osaka, a metropolitan city in Japan, there are several active faults (e.g., the Uemachi and Ikoma faults), which are inferred from the topography, the attitude of active faults in surface trenches, the seismic reflection profile at shallow depths (less than 2 km), and the three-dimensional distribution of the Quaternary sedimentary layers. The Uemachi and Ikoma faults are N–S-striking fault systems with total lengths of 42 km and 38 km, respectively, with the former being located ~12 km west of the latter; however, the geometries of each of the active faults within the seismogenic zone is not clear. In this study, to examine the geometries of the Uemachi and Ikoma faults from the surface to the seismogenic zone, we analyze the development of the geological structures of sedimentary layers based on numerical simulations of a two-dimensional visco-elasto-plastic body under a horizontal compressive stress field, including preexisting linear high-strained weak zones (i.e., faults) and surface sedimentation processes, and evaluate the relationship between the observed geological structures of the Quaternary sediments (i.e., the Osaka Group) in the Osaka Plain and the model results. Based on a comparison between the simulation results and the geological observations/interpretation, we propose geometries of the Uemachi and Ikoma faults from the surface to the seismogenic zone. When the friction coefficient of the faults is ~0.5, the dip angles of the Uemachi and Ikoma faults near the surface are ~30°–40° and the Uemachi fault has a downward convex curve at the bottom of the seismogenic zone but does not converge to the Ikoma fault. Based on the analysis in this study, the dip angle of the Uemachi fault zone is estimated to be approximately 30°–40°, and the downward extension of the Uemachi fault zone nearly coincides with the epicenter of the 2018 northern Osaka earthquake.

BACKGROUND Ependymomas are currently classified into 9 subgroups by DNA methylation profiles. Although spinal cord ependymoma (SP-EPN) is distinct from other tumors, diversity within SP-EPN is still unclear. Here, we used transcriptomic and epigenomic profiles to investigate the diversity among Japanese SP-EPN cases. MATERIALS AND METHODS We analyzed 57 SP-EPN patients (32 males and 25 females, aged from 18 to 78 years, median: 52), including two cases of neurofibromatosis type 2, five cases of grade 3 (WHO grade). We obtained transcriptome (RNA-seq) and DNA methylation (Infinium Methylation EPIC array) data from fresh frozen specimens of SP-EPN resected at the University of Tokyo Hospital and our collaborative groups. RESULTS Three cases had a previous intracranial ependymoma operation. Hierarchical clustering of the DNA methylation data showed that these three cases of intracranial origin as a different cluster from spinal origin. The 45 grade 2 spinal ependymoma showed a relatively homogenous methylation pattern. However, the methylation status of HOX gene cluster regions is compatible with the segment of origin, which reflects the cells of origins are derived after the determination of segment identity. RNA sequencing of 57 cases revealed two subgroups within grade 2. Gene ontology analysis of differentially expressed genes suggested the difference in metabolic state such as rRNA translation and mitochondrial respiration between the two expression subgroups. CONCLUSION Epigenetic analysis indicated the accurate body segment origin of SP-EPN. We observed that metabolic states could divide grade 2 spinal cord ependymoma into 2 subgroups and will present the relationship to clinicopathological information.

Spinal extradural arteriovenous fistulas (AVFs) may be more difficult to prospectively identify than dural AVFs because they are less common than dural AVFs. The primary purpose was to further characterize the diagnostic imaging of spinal extradural AVFs with intradural retrograde venous drainage. The magnetic resonance (MR) imaging and angiographic results of 23 patients with suspected spinal dural AVFs were analyzed in order to distinguish dural and extradural AVFs. The diagnostic accuracy of MR angiography was retrospectively compared between dural and extradural AVFs. All 23 patients showed high intensity in the spinal cord on T2-weighted MR images. Eighteen out of 23 patients were diagnosed with dural AVFs, while the remaining 5 were diagnosed with extradural AVFs by angiography. Extradural AVFs were fed by a branch of the segmental artery to the vertebral body, characterized by a fistula located in the ventral extradural space, and drained retrogradely via an epidural venous pouch into intradural veins. The segmental artery was localized within 1 vertebral level using MRA in 12 out of 18 patients (67%) with dural AVFs and in 1 out of 5 patients (20%) with extradural AVFs (p=0.09). The reasons behind the lower accuracy was mainly the image misinterpretation. Congestion of the spinal cord in spinal extradural AVFs with intradural retrograde venous drainage was similar to that in dural AVFs, whereas its angioarchitecture differed from that of dural AVFs. A clearer understanding of the imaging features of extradural AVFs is important for improving the diagnostic accuracy and clarifying treatment targets.

Background: Spinal arteriovenous fistulas (AVFs) are vascular lesions that often pose significant surgical challenges. This is particularly true for those located close to the anterior spinal artery. Here, we analyzed the surgical options for treating an anterior perimedullary AVF (pAVFs). Case Description: A 66-year-old male with the right lower extremity weakness was diagnosed with a spinal dural AVF at the L1 level. It was initially treated with open surgery followed by CyberKnife radiosurgery at another institution. Five years later, he presented with a persistent pAVF fistula now involving the T11 level; the major feeder originated on the left at the T7–T8 level (e.g., involving a left-sided “duplicated” anterior spinal artery). Utilizing a three-dimensional (3D) computer tomography (CT) guided approach; he underwent a left-sided posterolateral T10–T12 laminectomy, sufficient to allow for 30–40° of anterior spinal cord rotation. This was performed under neurophysiological monitoring without any significant changes. Surgery included indocyanine green video angiography, temporary feeder clipping, and complete occlusion of the AVF, followed by complete clipping/resection as confirmed on postoperative magnetic resonance imaging. Conclusion: Utilizing a 3D CT image, a ventral pulmonary arteriovenous malformation was excised utilizing a left-sided posterolateral approach allowing for 30–40° of cord rotation.

Axial neck and back pain after cervical spinal surgery is a common postoperative complication and can last for years. It is sometimes refractory to conventional treatments such as pharmacotherapy and spinal cord stimulation (SCS). Peripheral nerve field stimulation (PNFS) was recently introduced as an alternative treatment in the management of axial back pain into the occipital/craniofacial region and trunk in occipital neuralgia, post-herpetic neuralgia, and low back pain after lumbar spine surgery. However, PNFS has not been applied to axial neck pain. The patient suffered from occipital neuralgia and axial back pain after cervical spine surgery. In addition to PNFS of the greater occipital nerves for occipital neuralgia, we subcutaneously implanted two electrodes into the bilateral neck regions parallel with a sequential arrangement of the cervical spine. The electrodes were placed immediately above the trapezius muscles and electrical paresthesia was enhanced by posterior neck muscle twitches, fully covering the areas with axial neck pain. Both electrodes successfully achieved an almost 70% decrease in occipital and axial neck pain. Since axial neck pain after cervical spinal surgery often affects patients' health-related quality of life, neuromodulation in the form of PNFS may have the potential to become a novel alternative to conventional pain treatments for medically refractory axial neck pain.

Calcineurin is required for long-term depression and activity-dependent spine shrinkage, and calcineurin mutations have been identified in patients with schizophrenia. Moreover, mice with conditional knockout of calcineurin B (CNB-KO) exhibit behavioral abnormalities suggestive of schizophrenia. Changes in the dendritic spines of these mice, however, have not been investigated. We therefore examined the dendritic spines of CNB-KO mice, and observed a significant reduction in small spines and an increase in large spines in the prefrontal and visual cortices. The effect of CNB-KO on the spine sizes was relatively moderate, possibly due to the presence of spontaneous fluctuations (dynamics) in the dendritic spines themselves. Thus, CNB-KO mice showed a spine phenotype similar to those recently reported in patients with schizophrenia.

application/pdf, Earth and Planetary Science Letters. 2020, 531, P.115935[1]-115935[10]

Objective Although sleep disorder is one of the most serious comorbidities of refractory chronic pain, it is usually assessed only from the patients' subjective point of view. Therefore, we aimed to objectively evaluate the sleep efficiency of patients with chronic pain. Methods Using an actigraph, a highly sensitive accelerometer, we assessed the sleep efficiency of six patients with chronic pain before and after the introduction of spinal cord stimulation (SCS). Results While pain improved in only five out of six patients after SCS, sleep efficiency improved in all cases. Interestingly, in one case, sleep efficiency improved even though pain intensity remained unchanged. Conclusion With the use of an actigraph, improvements in sleep of patients with chronic pain undergoing SCS were demonstrated. One case showing improvement in sleep despite pain palliation may suggest that SCS might have independently affected the sleep system, although further studies are necessary.

Dendritic spine generation and elimination play an important role in learning and memory, the dynamics of which have been examined within the neocortex in vivo. Spine turnover has also been detected in the absence of specific learning tasks, and is frequently exaggerated in animal models of autistic spectrum disorder (ASD). The present study aimed to examine whether the baseline rate of spine turnover was activity-dependent. This was achieved using a microfluidic brain interface and open-dura surgery, with the goal of abolishing neuronal Ca2+ signaling in the visual cortex of wild-type mice and rodent models of fragile X syndrome (Fmr1 knockout [KO]). In wild-type and Fmr1 KO mice, the majority of baseline turnover was found to be activity-independent. Accordingly, the application of matrix metalloproteinase-9 inhibitors selectively restored the abnormal spine dynamics observed in Fmr1 KO mice, without affecting the intrinsic dynamics of spine turnover in wild-type mice. Such findings indicate that the baseline turnover of dendritic spines is mediated by activity-independent intrinsic dynamics. Furthermore, these results suggest that the targeting of abnormal intrinsic dynamics might pose a novel therapy for ASD.

It is widely accepted that water-rich serpentinite domains are commonly present in the mantle above shallow subducting slabs and play key roles in controlling the geochemical cycling and physical properties of subduction zones. Thermal and petrological models show the dominant serpentine mineral is antigorite. However, there is no good consensus on the amount, distribution and alignment of this mineral. Seismic velocities are commonly used to identify antigorite-rich domains, but antigorite is highly-anisotropic and depending on the seismic ray path, its properties can be very difficult to distinguish from non-hydrated olivine-rich mantle. Here, we utilize this anisotropy and show how an analysis of seismic anisotropy that incorporates measured ray path geometries in the Ryukyu arc can constrain the distribution, orientation and amount of antigorite. We find more than 54% of the wedge must consist of antigorite and the alignment must change from vertically aligned to parallel to the slab. This orientation change suggests convective flow in the hydrated forearc mantle. Shear wave splitting analysis in other subduction zones indicates large-scale serpentinization and forearc mantle convection are likely to be more widespread than generally recognized. The view that the forearc mantle of cold subduction zones is dry needs to be reassessed.

Visual Abstract, Excitatory synapses are often formed at small protrusions of dendrite, called dendritic spines, in most projection neurons, and the spine-head volumes show strong correlations with synaptic connectivity. We examined the dynamics of spine volume in the adult mouse visual cortex using time-lapse in vivo two-photon imaging with a resonant Galvano scanner. Contrary to expectations, we found that the spines in the adult neocortex showed fluctuations to a similar degree as that observed in young hippocampal preparations, but there were systematic differences in how the dynamics were dependent on spine volumes, thus allowing for fewer fluctuations in small spines, which could account for the relatively low turnover rates of neocortical spines in vivo. We found that spine volumes fluctuated to a greater extent in a mouse model (Fmr1 knockout) of fragile X mental retardation than in wild-type mice, and the spine turnover rates were also higher in Fmr1 knock-out mice. Such features of spine dynamics in Fmr1 knock-out mice could be represented by a single slope factor in our model. Our data and model indicate a small but significant change in the average spine volume and more eminent differences in the statistical distribution in Fmr1 knock-out mice even in adulthood, which reflects the abnormal in vivo dynamics of spine volumes.

The strain geometry of a Cretaceous low- P /high- T metamorphosed accretionary complex in SW Japan is one of the key geological constraints in understanding the Cretaceous tectonics of the forearc region at the eastern margin of Eurasia. We studied the strain geometry of upper greenschist to lower amphibolite facies metamorphic rocks from the mid-Cretaceous low- P /high- T Ryoke metamorphic belt, which during the mid-Cretaceous were located at mid-crustal depths close to the volcanic front. Strain analysis focused on deformed radiolarian fossils in metachert and sandstone/chert clasts within metapelite. The maximum stretching direction ( X -direction) of the strain ellipsoid of the schistosity-forming deformation at the peak metamorphism is oriented E-W, and the XY -plane of the strain ellipsoid developed parallel to schistosity. The metachert and metapelite exhibit plane strain to general flattening strain that probably largely resulted from the schistosity-forming deformation. Based on the results of the previous strain analyses and this study, it reveals that the schistosity-forming deformation occurred under bedding-normal shortening, resulting in general flattening strain throughout the Ryoke metamorphic belt. The X -direction of the strain ellipsoid of the schistosity-forming deformation is oriented parallel to the length of the Ryoke metamorphic belt throughout the SW Japan arc. The schistosity formed parallel to bedding planes that developed horizontally in non-metamorphosed accretionary complexes of SW Japan, indicating horizontal XY -plane of the strain ellipsoid. These observations indicate the occurrence of horizontal shear deformation within the middle crust (∼15 km depth) at the time of the low- P /high- T metamorphism. The deep-seated horizontal shear zone and the shallower incipient Median Tectonic Line (MTL) fault system could result in a crustal-scale detachment fault in the forearc region of the mid-Cretaceous SW Japan arc. After the formation of the detachment, the left-lateral pull-apart forearc basins, Onogawa-Izumi Group distributed on the north side of the MTL and the southern marginal mylonite zone might be formed by the sinistral movement along the detachment fault.

Olivines with conspicuous iron-rich stripe patterns are found in serpentinized peridotites from Conical and South Chamorro Seamounts, Mariana forearc, western Pacific. The stable association of antigorite, diopside, and olivine in these peridotites indicates that antigorite, diopside, and olivine underwent serpentinization at approximately 450-550 °C. The iron-rich stripe patterns are formed in the olivine crystal (Fo90-92) as a parallel alignment of narrow straight parts of widths ranging from 0.5 to 2.0 μm. The iron-rich parts have compositions of Fo86-89. The iron-rich stripe patterns are well developed near the rim of the host olivine where fiber crystals of antigorite are pierced into olivine and these patterns are not found in the inside of olivine grain except in the periphery of cracks. Generally, olivine is highly deformed and has well-developed cleavages in (010), (100), and (001) directions. The stripe is commonly parallel to (100), but one olivine grain has two sets of stripes that are parallel to (100) and (001). Modes of formation of iron-rich stripe patterns in olivine suggest that the infiltration of iron-rich fluid along the cleavage trace or the subgrain boundary formed by dislocations is probably responsible for the formation of the iron-rich stripe patterns. The iron-poor parts intervened between the iron-rich parts are slightly lower in XMg[= Mg/(Mg + Fe2+)] than the inside of olivine grain that is homogeneous in composition and lacks iron-rich stripe patterns, suggesting that metasomatic alteration also occurred in iron-poor parts. Antigorite formation results in an extra iron component because XMg of antigorite (= 0.94-0.97) is significantly higher than that of host olivine. Therefore, the iron-rich fluid may have been produced by serpentinization and infiltrated through olivine crystal to form iron-rich stripe patterns.

Background Hemangioblastomas are hypervascular lesions and hence their surgical management is challenging. In particular, if complete resection is to be attained, all feeding and draining vessels must be occluded. Although most intramedullary spinal cord tumors are treated utilizing a posterior approach, we describe an anterior surgical strategy for resection of an intramedullary cervical hemangioblastoma. Case description A 36-year-old female with a spinal hemangioblastoma located in the anterior cervical spinal cord presented with a long-standing history of motor weakness of the right upper extremity. Magnetic resonance imaging revealed a large multilevel extensive syrinx and a focal intramedullary enhanced tumor at the C6 level. Angiography showed that the main feeder to the tumor was the left radicular artery (C8), which originated from the thyrocervical trunk, penetrated the dura mater, and branched both rostrally and caudally into the anterior spinal artery (ASA). Three-dimensional computer graphic images showed the tumor was located in the anterior part of the spinal cord, adjacent to and supplied by the ASA. The planned anterior surgical approach involved a total corpectomy of C6 and partial corpectomies of C5 and C7. The tumor was entirely removed despite multiple adhesions, and was successfully freed from the ASA. Patency of the ASA was confirmed utilizing intraoperative indocyanine green videoangiography. Intraoperatively, no monitoring changes were encountered. The pathological diagnosis was of a hemangioblastoma. No postoperative deficit occurred. Conclusions An anterior approach for the resection of an anteriorly located intramedullary spinal hemangioblastomas was successfully accomplished in this case.

Granitic mylonites from an upper greenschist facies mylonite zone in the Ryoke metamorphic belt, SW Japan show three types of microstructure with increasing mylonitization: (1) mylonite, (2) banded mylonite and (3) banded ultramylonite. The banded mylonites and ultramylonites include bands of quartz, biotite, K-feldspar, plagioclase > K-feldspar (>quartz + biotite) and K-feldspar > plagioclase > quartz. The inequality sign indicates abundance in modal proportion within a band. Microstructural and textural investigations by cathodoluminescence (CL), scanning electron microscopy (SEM) and electron back-scatter diffraction (EBSD) show that the microstructural changes from mylonites to banded ultramylonites have occurred through fracturing of plagioclase porphyroclasts, K-feldspar replacement by myrmekite, K-feldspar precipitation in fractures and tails and dislocation creep of quartz and K-feldspar. Development of the banded structure was promoted by high mobility via solution transfer of K-feldspar. Clear spatial distribution of constituent minerals in polyphase feldspar-rich bands, instead of homogeneous mixing of them, indicates that the grain boundary sliding was not the dominant deformation process.

This paper proposes a framework based on a new architecture that allows distributed smartcards to interact with one another as well as with application programs on their hosts. Since these interactions are handled distribution-transparently through message dispatching agents deployed on each host, the smartcards can autonomously conduct distributed protocols without turning to off-card application programs. The proposed framework thus reduces the complexity of application programs and makes it easier to develop smartcard-based services that offer a high level of functionality. The feasibility of the framework is evaluated and confirmed by implementing a smartcard-based optimistic fair trading protocol for electronic vouchers on this framework.

本見学コースでは，三波川変成岩が後退変成作用を受けつつ上昇して来た時に形成された変形構造（D1，D2およびD3時相に形成された構造）を観察する．このうち，著しい東西塑性流動で形成されたD1変形構造と，鉛直の開いた東西方向の褶曲群で特徴付けられるD3変形構造は識別が比較的容易であり，本見学コースで数地点において観察する．一方D2変形構造はこれまで必ずしも明確でなかったが，最近著者らは，その実体や上昇テクトニクスにおける意味を明らかにしつつあり，本見学コースの重要な観察・議論の対象として取り上げる．第1日目では汗見川流域の高度変成岩中に発達する，D2褶曲やスラストおよびデタッチメント正断層が観察の見所となる．第2日目には，中央構造線近傍国領川流域の変形帯で，D2正断層およびそれを転位させるD3褶曲を観察する．ここでは，D2の北北西方向への運動方向を示す石英スリッケンファイバーも観察する．

The subduction and exhumation of accretionary prism metasedimentary rocks are accompanied by large-strain ductile deformations which may be recorded in microstructures. Porphyroblast microstruc- tures have been a key to unravel the kinematics in such deformed belts. Shape-preferred orientation (SPO) of epidote and amphibole inclusions that define S-shaped trails in prograde cores of plagioclase porphyroblasts were analysed from the high-P/T Sambagawa metamorphic rocks. Inclusions are found to be elongate parallel to the (010) and (001) directions, respectively, and their long-axis orientations define an internal foliation Si (best-fit great circle) and lineation Li (maximum on the Si). S-shaped inclusion trails in the orthogonal sections do not exhibit the same geometries, but rather are grouped into two types, where the foliation intersection axes (FIAs) are nearly perpendicular and parallel to Li, respectively. These two types of S-shaped inclusion trails are seen in the sections inclined at low and high angles to the Li, respectively. However, the latter type commonly consists of composite trails, where the Si is first rotated about an FIA perpendicular to the Li (i.e. unique axis), and then about an FIA parallel to the Li. The S-shaped inclusion trails are interpreted to have formed by the successive overgrowth of matrix minerals and rotation of the plagioclase porphyroblast cores about a unique axis in non-coaxial deformation. The rotation of Si about an FIA nearly parallel to the Li is perhaps an apparent rotation, caused by the deflection of foliation around the growing prismatic plagioclase grain prior to inclusion into the porphyroblast. This study has for the first time documented the 3-D geometry of S-shaped inclusion trails in porphyroblasts from accretionary prism metasedimentary rocks and identified their origin, which helps to understand the flow kinematics in the deeper part of a subduction channel.

Orthopyroxene porphyroclasts in peridotite mylonites are elongated to variable extents depending on the crystallographic orientation. This paper presents a 3D numerical model of the development of lattice- and shape-preferred orientations of orthopyroxene porphyroclasts in a fine-grained olivine matrix for matrix deformations of simple shear, pure shear and uniaxial shortening. In this model, orthopyroxene grains are assumed to deform by dislocation glide on a unique slip system (100)[001] with additional rigid-body rotation. This rotation and deformation is determined so as to minimize the difference in displacement between the matrix and grains for an imposed incremental matrix deformation. The lattice- and shape-preferred orientations of orthopyroxene porphyroclasts in three mutually orthogonal sections of a peridotite mylonite sample are consistent with the simulation results for simple shear. The proposed model can be regarded as an extension of the rigid inclusion model to an anisotropically deformable model, and may represent a mechanism for the development of strong shape-preferred orientation with antithetic inclination from the shear direction. The proposed 3D model accounts for both lattice- and shape-preferred orientation, and may therefore be applicable to identifying finite strain geometry and the orientation of vorticity vectors independently in natural shear zones.

Orthopyroxene porphyroclasts in peridotite mylonites are elongated to a variable extent and this variation depends on the crystallographic orientation of grains. We simulated the development of lattice- and shape-preferred orientation of orthopyroxene grains in peridotite using a purely geometrical two-dimensional model. In this model, under the given matrix deformation, orthopyroxene grains are assumed to deform and rotate so as to minimize the difference in displacement between the matrix and grains. In addition, the deformation of an orthopyroxene grain is limited to dislocation glide on the unique slip system (100)[001]. The results show that glide-plane orientation (θ) of grains with a large aspect ratio (R) become separated into two orientations during progressive matrix deformation ranging from simple shear to pure shear. In addition, the degree of asymmetry in R–θ distribution increases with the degree of non-coaxiality of matrix deformation. In contrast, the long-axis orientation (φ) of grains becomes concentrated around the elongation axis of matrix deformation. A natural example from the Horoman peridotite complex, northern Japan, shows an R–θ–φ relation consistent with matrix deformation by progressive simple shear. Thus, the R–θ–φ relations of orthopyroxene porphyroclasts may be useful for the estimation of strain magnitude as well as the degree of non-coaxiality of deformed peridotites.

Rheumatoid leptomeningitis is a rare complication of rheumatoid arthritis (RA). We describe a woman with rheumatoid leptomeningitis presenting with acute-onset behavioral changes and consciousness disturbance in the early stage of RA. On fluid-attenuated inversion recovery images or diffusion-weighted images, high-signal-intensity lesions in the subarachnoid spaces of the right frontal lobe were observed. Biopsies of brain tissues and the dura mater located in the right frontal lobe were obtained. On the basis of the findings of histopathological analysis, a diagnosis of necrotizing granulomas involving the leptomeninges consistent with rheumatoid leptomeningitis was made. An early diagnosis of rheumatoid leptomeningitis and immediate initiation of treatment may prevent neurological sequelae.

Cerebral presenilin-1 protein (PS-1) is normally composed of the amino-terminal fragment (NTF) with Mr 28 kDa and the carboxy-terminal fragment (CTF) with 18 kDa. We analyzed human PS-1 in brains with early-onset familial Alzheimer's disease (FAD) with and without PS-1 mutations to study whether mutated PS-1 was abnormally metabolized. Cerebral PS-1 were found to be cleaved into two fragments of NTF and CTF independently of the occurrence of PS-1 mutation in human brains. A small portion of PS-1 was recently found to suffer another processing by caspase-3, an apoptosis-related cysteine protease. In contrast to the recent finding that the Volga-German mutation on presenilin-2 (PS-2) affects the increasing caspase-3 PS-2 fragment, the PS-1 mutation did not cause a significant change in PS-1 fragmentation. We conclude that PS-1 fragmentation and other (probably caspase-3-mediated) digestion following apoptosis occur independently of PS-1 mutations.

The development of rigid crinoid-type pressure fringes is simulated for variable shape and orientation of the rigid original grains, matrix flow pattern and total strain, using Etchecopar and Malavieille's model, which is based on a principle of geometrical minimization of the gap between a rigid grain and its ductile matrix. A method of determining the non-coaxiality of the matrix flow is constructed assuming two-dimensional flow with constant area and time-independent flow parameters. In this method, the systematic variation in the geometry of the pressure fringes as a function of the shape and orientation of the rigid original grains, is used as a criterion. The application to the natural examples shows consistent variation in the geometry of pressure fringes with the simulation. This indicates the validity of the method as long as the assumptions hold.

Partitioning of non-coaxiality and other flow parameters in deforming layered rock masses with nearly incompressible Newtonian rheology is examined in two dimensions by the finite element method. The results show that layers with viscosity contrast in suitable orientation deform by different and even by a reverse sense of non-coaxiality. This remarkable partitioning of non-coaxiality is due to a large rotation rate of instantaneous stretching axes in a heterogeneous body as a result of geometry changing through deformation rather than through rotation of material lines.

✓ Perineural cysts have become a common incidental finding during lumbosacral magnetic resonance (MR) imaging. Only some of the symptomatic cysts warrant treatment. The authors describe the successful operative treatment of a patient with, to the best of their knowledge, the largest perineural cyst reported to date. A 29-year-old woman had been suffering from long-standing constipation and low-back pain. During an obstetric investigation for infertility, the clinician discovered a huge presacral cystic mass. Computed tomography myelography showed the lesion to be a huge Tarlov cyst arising from the left S-3 nerve root and compressing the ipsilateral S-2 nerve. The cyst was successfully treated by ligation of the cyst neck together with sectioning of the S-3 nerve root. Postoperative improvement in her symptoms and MR imaging findings were noted. Identification of the nerve root involved by the cyst wall, operative indication, operative procedure, and treatment of multiple cysts are important preoperative considerations.

An 82-year-old woman with Turner syndrome and schizophrenia, and her 46-year-old daughter with schizophrenia are described. 45X/46XX chromosomal mosaicism was identified in the peripheral leukocytes of the mother, who showed several Turner dysmorphisms and cavum septi pellucidum in the brain. She had a normal reproductive life-span. The daughter resembled the mother in terms of schizophrenic symptoms, but she did not show any signs of Turner dysmorphism or chromosomal abnormality. The phenotype-karyotype relationship of Turner syndrome and the genetic relationship with psychosis are discussed.

The geometric forms of pressure shadows (strain shadows) around deformation resistant object involve important information such as sense of shear, degree of non-coaxiality and pass of incremental strains during progressive deformation. Pressure shadows filled with fibrous crystals are known as pressure fringes which commonly occur in slates and pelitic schists.The growth lines of fiber in mineral veins and in pressure fringes show the incremental strain pass (Ramsay and Huber, 1983; Passchier and Trouw, 1995; Ishii, 1996). There are three types of fiber growth in fibrous veins and pressure fringes; syntaxial, antitaxial and composite. Syntaxial growth occurs inward from the vein wall in veins, and outward from a rigid object in pressure fringes, where fibers consist of the same minerals with the wall/object. In contrast, antitaxial growth occurs outward from the vein center in veins and inward from the matrix in pressure fringes, where fibers consist of other minerals than the wall/ object. Composite growth has a syntaxial and an antitaxial components. Syntaxial and antitaxial pressure fringes are also known as crinoid type and pyrite type pressure fringes, respectively (Ramsay and Huber, 1983).This pictorial presents pyrite- and crinoid type pressure fringes from the late Paleozoic strata in the South Kitakami Belt, pyrite type pressure fringes from the Sambagawa pelitic schist and porphyroclast-pressure shadow system from granitic mylonites along the Median Tectonic Line in the Ryoke belt. All photomicrographs are taken for XZ thin sections cut parallel to the stretching lineation and perpendicular to the foliation.

Using X-ray diffraction analysis, the mutual relations among illite crystallinity, degree of preferred orientation of chlorite, grain size change of chlorite and illite during metamorphism and development of slaty cleavage have been investigated for argillaceous rocks in the South Kitakami Mountains, northeast Japan. The metamorphic grade of IC (illite crystallinity index) = 0.29 is a critical one, beyond which the homogenization of chlorite composition, coarsening of chlorite and illite grains and degree of preferred orientation of chlorite are abruptly advanced. Grain coarsening is also promoted by the development of slaty cleavage, especially in the range of coarser grain size. The oriented growth by the effects of both the anisotropy of intrinsic growth rate of mineral grains and that of the environment in which grains grow, is considered to bring about the preferred orientation of chlorite and illite.

An active glucoside that enhanced release of histamine from rat peritoneal mast cells was isolated from a toxic fraction of bracken fern, Pteridium aquilinum, by partition column chromatography on Sephadex G-25. It was a yellowish amorphous powder on freeze-drying, readily soluble in water or ethanol, and insoluble in ether. It was hydrolysed with beta-glucosidase to release D-glucose. It was assumed to be a kind of beta-glucopyranoside with a carbocyclic structure in the aglycone moiety.

Thiamine and its phosphate esters in rat tissues were determined by high-performances liquid chromatography after conversion to thiochrome and its phosphate esters as described previously (Ishii, K. et al. (1979) Anal. Biochem., 97, 191--195). Total thiamine concentrations determined in the brain, liver, heart and kidney were 6.39, 25.5, 15.7, and 14.9 nmol/g wet weight, respectively. In all the tissues tested, thiamine, its monophosphate, pyrophosphate, and triphosphate were found to be present at the rates of 1.2--7.7, 5.9--11.0, 85.7--90.0, and 0.7--1.6%, respectively. Although these percentages of thiamine phosphates were similar to those reported previously using different procedures, the percentage of thiamine triphosphate content in rat tissues was found to be fairly lower than that reported. The time required for the whole process of analysis averaged 90 min after isolation of the organs from the animal.