Real-world safety of nusinersen in Japan: results from an interim analysis of a post-marketing surveillance and safety database

PURPOSE

Nusinersen is the first disease-modifying therapy to treat spinal muscular atrophy (SMA). This report describes the safety and effectiveness of nusinersen in Japanese clinical use using two data sources: an ongoing Japanese post-marketing surveillance (PMS) and the safety database of the marketing authorisation holder, Biogen .

MATERIALS AND METHODS

The PMS is evaluating the safety and effectiveness of nusinersen in all patients treated with nusinersen in Japan between August 2017 and August 2025; this interim analysis included data up to May 30, 2019. Biogen safety database data up to June 30, 2019 were also included to capture adverse events (AEs) from after the interim analysis cutoff date. Collected data included medical history, dosage and administration, and AEs. Safety assessment included AEs and serious AEs (SAEs). Effectiveness analyses included motor function assessments and clinical global impressions of improvement.

RESULTS

Of 271 patients in the PMS population, 94 had SMA type I (34.7%), and 177 had SMA types II-IV (65.3%). AEs occurred in 67 patients (24.7%) and SAEs in 23 patients (8.5%). The Biogen safety database contained reports of 345 AEs; the most common were pneumonia, headache, and pyrexia, consistent with symptoms of SMA and lumbar puncture. In the analysis set, 26.2% of patients receiving nusinersen showed motor function improvements and 99.6-100.0% showed overall improvement.

CONCLUSION

In this interim analysis of the PMS and Biogen safety database, nusinersen had a favourable benefit-risk profile in Japanese patients with SMA.

GLI3 Is Associated With Neuronal Differentiation in SHH-Activated and WNT-Activated Medulloblastoma

Glioma-associated oncogene homolog 3 (GLI3), whose main function is to inhibit GLI1, has been associated with neuronal differentiation in medulloblastoma. However, it is not clear what molecular subtype(s) show increased GLI3 expression. GLI3 levels were assessed by immunohistochemistry in 2 independent cohorts, including a total of 88 cases, and found to be high in both WNT- and SHH-activated medulloblastoma. Analysis of bulk mRNA expression data and single cell RNA sequencing studies confirmed that GLI1 and GLI3 are highly expressed in SHH-activated medulloblastoma, whereas GLI3 but not GLI1 is highly expressed in WNT-activated medulloblastoma. Immunohistochemical analysis has shown that GLI3 is expressed inside the neuronal differentiated nodules of SHH-activated medulloblastoma, whereas GLI1/2 are expressed in desmoplastic areas. In contrast, GLI3 is diffusely expressed in WNT-activated medulloblastoma, whereas GLI1 is suppressed. Our data suggest that GLI3 may be a master regulator of neuronal differentiation and morphology in these subgroups.

MBRS-06. Gli3 INDUCES NEURONAL DIFFERENTIATION IN WNT- AND SHH- ACTIVATED MEDULLOBLASTOMA

BACKGROUND

We have previously investigated the expression of Gli3, a downstream target of the Sonic Hedgehog pathway, which main function is to suppress Gli1/2 in medulloblastomas. We found that Gli3 is associated with neuronal and glial differentiation in desmoplastic / nodular (D/N) type medulloblastomas (Miyahara et al., Neuropathology, 2013). In the present study, we investigated the expression of Gli3 in molecular subgroups.

METHOD

Thirty-one medulloblastomas treated at Niigata University between 1982 and 2013 were studied. Molecular classification into 4 subgroups (WNT-activated, SHH-activated, Group 3 and Group 4) using Nanostring and immunohistochemistry was performed. Furthermore, Gli3 and Gli1 expression in molecular subgroups was assessed using public data bases.

RESULTS

Nanostring was considered reliable (confidence > 0.9) in 28 cases. Four cases were classified as WNT-, 5 cases as SHH-activated, 4 cases as Group 3 and 16 cases as Group 4. Gli3 was positive in 7 out of 9 (78%) WNT-/SHH- cases, but positive in only 8 out of 19 (42.1%) non-WNT-/SHH- subgroup cases (p = 0.1145, Fisher’s exact test). R2 database analysis confirmed that Gli3 was significantly elevated in WNT- and SHH-activated medulloblastoma. Gli1 was elevated in SHH-activated cases but suppressed in WNT-activated cases. IHC analysis revealed that Gli3 was elevated inside nodules showing neuronal differentiation in D/N type medulloblastoma. Results of single cell RNA analyses were consistent with those of IHC, Nanostring and R2.

CONCLUSION

These results suggest that Gli3 is elevated inside the nodules of SHH-activated medulloblastoma, whereas in WNT-activated cases, Gli3 diffusely suppresses HH signaling.

Significance of molecular classification of ependymomas: C11orf95-RELA fusion-negative supratentorial ependymomas are a heterogeneous group of tumors

Extensive molecular analyses of ependymal tumors have revealed that supratentorial and posterior fossa ependymomas have distinct molecular profiles and are likely to be different diseases. The presence of C11orf95-RELA fusion genes in a subset of supratentorial ependymomas (ST-EPN) indicated the existence of molecular subgroups. However, the pathogenesis of RELA fusion-negative ependymomas remains elusive. To investigate the molecular pathogenesis of these tumors and validate the molecular classification of ependymal tumors, we conducted thorough molecular analyses of 113 locally diagnosed ependymal tumors from 107 patients in the Japan Pediatric Molecular Neuro-Oncology Group. All tumors were histopathologically reviewed and 12 tumors were re-classified as non-ependymomas. A combination of RT-PCR, FISH, and RNA sequencing identified RELA fusion in 19 of 29 histologically verified ST-EPN cases, whereas another case was diagnosed as ependymoma RELA fusion-positive via the methylation classifier (68.9%). Among the 9 RELA fusion-negative ST-EPN cases, either the YAP1 fusion, BCOR tandem duplication, EP300-BCORL1 fusion, or FOXO1-STK24 fusion was detected in single cases. Methylation classification did not identify a consistent molecular class within this group. Genome-wide methylation profiling successfully sub-classified posterior fossa ependymoma (PF-EPN) into PF-EPN-A (PFA) and PF-EPN-B (PFB). A multivariate analysis using Cox regression confirmed that PFA was the sole molecular marker which was independently associated with patient survival. A clinically applicable pyrosequencing assay was developed to determine the PFB subgroup with 100% specificity using the methylation status of 3 genes, CRIP1, DRD4 and LBX2. Our results emphasized the significance of molecular classification in the diagnosis of ependymomas. RELA fusion-negative ST-EPN appear to be a heterogeneous group of tumors that do not fall into any of the existing molecular subgroups and are unlikely to form a single category.

The use of 5-aminolevulinic acid to assist gross total resection of pediatric astroblastoma

PURPOSE

Astroblastoma is an uncommon pediatric neuroepithelial tumor. The prognosis and appropriate treatment of astroblastoma were not well understood. Previous reports suggested the best treatment for astroblastoma is surgical total resection. The authors report a case of pediatric astroblastoma that underwent gross total resection with the use of fluorescent guidance by 5-aminolevulinic acid (5-ALA).

CASE REPORT

A 13-year-old girl presented with the tumor that was well-circumscribed cystic and solid mass with marked gadolinium enhancement in the right occipital lobe. At surgery, fluorescence of the tumor was clearly distinctive from the normal cerebral tissue. All fluorescent tissue including residual cyst wall was removed. Postoperative MRI showed gross total resection of the tumor. No serious side effect or complications occurred. The histopathologic diagnosis was suggestive of astroblastoma. The patients had no evidence of recurrence of tumor without adjuvant radiotherapy during the last 1 year of follow-up time.

CONCLUSION

5-ALA is useful to achieve gross total resection including cystic lesion of pediatric astroblastoma. A larger prospective study is warranted to establish the use of 5-ALA in pediatric brain tumor.

Integrated (epi)-Genomic Analyses Identify Subgroup-Specific Therapeutic Targets in CNS Rhabdoid Tumors

We recently reported that atypical teratoid rhabdoid tumors (ATRTs) comprise at least two transcriptional subtypes with different clinical outcomes; however, the mechanisms underlying therapeutic heterogeneity remained unclear. In this study, we analyzed 191 primary ATRTs and 10 ATRT cell lines to define the genomic and epigenomic landscape of ATRTs and identify subgroup-specific therapeutic targets. We found ATRTs segregated into three epigenetic subgroups with distinct genomic profiles, SMARCB1 genotypes, and chromatin landscape that correlated with differential cellular responses to a panel of signaling and epigenetic inhibitors. Significantly, we discovered that differential methylation of a PDGFRB-associated enhancer confers specific sensitivity of group 2 ATRT cells to dasatinib and nilotinib, and suggest that these are promising therapies for this highly lethal ATRT subtype.

Thoracic meningocele in lumbo-costo-vertebral syndrome in a child: possible enlargement with repeated motion by anchoring to the diaphragm

Lumbo-costo-vertebral syndrome (LCVS) is a rare disorder in children that is characterized by hemivertebrae, congenital absence of ribs, meningocele, and hypoplasia of the truncal and abdominal wall presenting as a congenital lumbar hernia. An otherwise healthy 12-month-old girl was referred to the authors' hospital with soft swelling on her left middle back; scoliosis had been present since birth. Imaging revealed a thoracic meningocele, ectopia of the spleen suggesting lumbar hernia, multiple anomalies of the thoracic vertebral columns, and defects of the ribs; thus, LCVS was diagnosed. Surgical observation revealed that the meningocele was firmly anchored to part of the diaphragm, which created stretching tension in the meningocele continuously with exhalation. Once detached, the meningocele shrank spontaneously and never developed again after cauterization. In this case, continuous or pulsatile pressure in the presence of a vertebral defect was thus considered to be an important factor for formation of the thoracic meningocele.

Prognostic value of medulloblastoma extent of resection after accounting for molecular subgroup: a retrospective integrated clinical and molecular analysis

Background

Incomplete surgical resection of medulloblastoma is controversially considered a marker of high-risk disease; driving aggressive surgical resections, “second-look” surgeries, and/or intensified chemoradiotherapy. All prior publications evaluating the clinical importance of extent of resection (EOR) failed to account for molecular subgroup. We analysed the prognostic value of EOR across 787 medulloblastoma samples in a subgroup-specific manner.

Methods

We retrospectively identified patients from Medulloblastoma Advanced Genomics International Consortium (MAGIC) centres with a histological diagnosis of medulloblastoma and complete extent of resection and survival data. Specimens were collected from 35 international institutions. Medulloblastoma subgroup affiliation was determined using nanoString gene expression profiling on frozen or formalin-fixed paraffin-embedded tissues. Extent of resection (EOR) based on post-operative imaging was classified as gross total (GTR), near total (NTR, <1·5cm²), or subtotal (STR, ≥ 1·5cm²). Overall survival (OS) and progression-free survival (PFS) multivariable analyses including subgroup, age, metastatic status, geographical location of therapy (North America/Australia vs world), and adjuvant therapy regimen were performed. The primary endpoint was the impact of surgical EOR by molecular subgroup and other clinical variables on OS and PFS.

Findings

787 medulloblastoma patients (86 WNT, 242 SHH, 163 Group 3, and 296 Group 4) were included in a multivariable Cox model of PFS and OS. The marked benefit of EOR in the overall cohort was greatly attenuated after including molecular subgroup in the multivariable analysis. There was an observed PFS benefit of GTR over STR (hazard ration [HR] 1·45, 95% CI; 1·07–1·96, p=0·02) but there was no observed PFS or OS benefit of GTR over NTR (HR 1·05, 0·71–1·53, p=0·82 and HR 1·14, 0·75–1·72, p=0.55). There was no statistically significant survival benefit to greater EOR for patients with WNT, SHH, or Group 3 patients (HR 1·03, 0·67–1·58, p=0·9 for STR vs. GTR). There was a PFS benefit for GTR over STR in patients with Group 4 medulloblastoma (HR1·97, 1·22–3·17, p=0·01), particularly those with metastatic disease (HR 2·22, 1–4·93, p=0·05). A nomogram based on this multivariable cox proportional hazards model shows the comparably smaller impact of EOR on relative risk for PFS and OS than subgroup affiliation, metastatic status, radiation dose, and adjuvant chemotherapy.

Interpretation

The prognostic benefit of EOR for patients with medulloblastoma is attenuated after accounting for molecular subgroup affiliation. Although maximal safe surgical resection should remain the standard of care, surgical removal of small residual portions of medulloblastoma is not recommended when the likelihood of neurological morbidity is high as there is no definitive benefit to GTR over NTR. Our results suggest a re-evaluation of the long-term implications of intensified craniospinal irradiation (36 Gy) in children with small residual portions of medulloblastoma.

Funding

Funding Canadian Cancer Society Research Institute, Terry Fox Research Institute, Canadian Institutes of Health Research, National Institutes of Health, Pediatric Brain Tumor Foundation, Garron Family Chair in Childhood Cancer Research.

A role for matrix remodelling proteins in invasive and malignant meningiomas

AIMS

Meningiomas are one of the most common brain tumours in adults. Invasive and malignant meningiomas present a significant therapeutic challenge due to high recurrence rates and invasion into surrounding bone, brain, neural and soft tissues. Understanding the molecular mechanism of invasion could help in designing novel therapeutic approaches in order to prevent the need for repeat surgery, decrease morbidity and improve patient survival. The aim of this study was to identify the key factors and underlying mechanisms which govern invasive properties of meningiomas.

METHODS

Formalin-fixed paraffin-embedded (FFPE) as well as frozen tumour tissues from bone-invasive, non-invasive and malignant meningiomas were used for RNA microarray, quantitative real-time PCR or Western blot analyses. Malignant meningioma cell lines (F5) were subject to MMP16 downregulation or overexpression and used for in vitro and in vivo functional assays. Subdural xenograft meningioma tumours were generated to study the invasion of tumour cells into brain parenchyma using cell lines with altered MMP16 expression.

RESULTS

We establish that the expression level of MMP16 was significantly elevated in both bone-invasive and brain invasive meningiomas. Gain- and loss-of-function experiments indicated a role for MMP16 in meningioma cell movement, invasion and tumour cell growth. Furthermore, MMP16 was shown to positively regulate MMP2, suggesting this mechanism may modulate meningioma invasion in invasive meningiomas.

CONCLUSIONS

Overall, the results support a role for MMP16 in promoting invasive properties of the meningioma tumours. Further studies to explore the potential value for clinical use of matrix metalloproteinases inhibitors are warranted.

Germinoma in the bilateral basal ganglia presented with cognitive deterioration

PURPOSE

Here, we report a case of pediatric germinoma located in the bilateral basal ganglia, which presented with severe cognitive deteriorations.

CASE REPORT

A 15-year-old boy presented with decreased school performance and mild cognitive disturbances. Magnetic resonance images (MRI) of the brain revealed T2 hyperintensity in the bilateral basal ganglia. The patient was initially observed by a local hospital and had screening for metabolic diseases or inflammatory diseases. Lesions with similar characteristics were also found in the pituitary stalk and infundibulum, and these lesions were enhanced with gadolinium (Gad). MR spectroscopy suggested that these should be neoplastic lesions other than metabolic or inflammatory diseases. Biopsy was performed with ventriculoscope, which proved all lesions of infundibulum, pineal, and basal ganglia were pathologically germinoma. The lesions responded well to the chemotherapy and radiation, and his cognitive function improved significantly.

CONCLUSION

A case of germinoma in the bilateral basal ganglia which significantly affect cognitive functions is reported. Differential diagnoses of cognitive symptoms are various, but germinoma could be considered as a possible pathology for it. Early MRI and tumor marker exams are recommended, unless organic brain diseases are completely denied. MR spectroscopy and biopsy with ventriculoscope are useful for diagnosis.

Generation of neuropeptidergic hypothalamic neurons from human pluripotent stem cells

Hypothalamic neurons orchestrate many essential physiological and behavioral processes via secreted neuropeptides, and are relevant to human diseases such as obesity, narcolepsy and infertility. We report the differentiation of human pluripotent stem cells into many of the major types of neuropeptidergic hypothalamic neurons, including those producing pro-opiolemelanocortin, agouti-related peptide, hypocretin/orexin, melanin-concentrating hormone, oxytocin, arginine vasopressin, corticotropin-releasing hormone (CRH) or thyrotropin-releasing hormone. Hypothalamic neurons can be generated using a 'self-patterning' strategy that yields a broad array of cell types, or via a more reproducible directed differentiation approach. Stem cell-derived human hypothalamic neurons share characteristic morphological properties and gene expression patterns with their counterparts in vivo, and are able to integrate into the mouse brain. These neurons could form the basis of cellular models, chemical screens or cellular therapies to study and treat common human diseases.

Molecular subgroups of atypical teratoid rhabdoid tumours in children: an integrated genomic and clinicopathological analysis

BACKGROUND

Rhabdoid brain tumours, also called atypical teratoid rhabdoid tumours, are lethal childhood cancers with characteristic genetic alterations of SMARCB1/hSNF5. Lack of biological understanding of the substantial clinical heterogeneity of these tumours restricts therapeutic advances. We integrated genomic and clinicopathological analyses of a cohort of patients with atypical teratoid rhabdoid tumours to find out the molecular basis for clinical heterogeneity in these tumours.

METHODS

We obtained 259 rhabdoid tumours from 37 international institutions and assessed transcriptional profiles in 43 primary tumours and copy number profiles in 38 primary tumours to discover molecular subgroups of atypical teratoid rhabdoid tumours. We used gene and pathway enrichment analyses to discover group-specific molecular markers and did immunohistochemical analyses on 125 primary tumours to evaluate clinicopathological significance of molecular subgroup and ASCL1-NOTCH signalling.

FINDINGS

Transcriptional analyses identified two atypical teratoid rhabdoid tumour subgroups with differential enrichment of genetic pathways, and distinct clinicopathological and survival features. Expression of ASCL1, a regulator of NOTCH signalling, correlated with supratentorial location (p=0·004) and superior 5-year overall survival (35%, 95% CI 13-57, and 20%, 6-34, for ASCL1-positive and ASCL1-negative tumours, respectively; p=0·033) in 70 patients who received multimodal treatment. ASCL1 expression also correlated with superior 5-year overall survival (34%, 7-61, and 9%, 0-21, for ASCL1-positive and ASCL1-negative tumours, respectively; p=0·001) in 39 patients who received only chemotherapy without radiation. Cox hazard ratios for overall survival in patients with differential ASCL1 enrichment treated with chemotherapy with or without radiation were 2·02 (95% CI 1·04-3·85; p=0·038) and 3·98 (1·71-9·26; p=0·001). Integrated analyses of molecular subgroupings with clinical prognostic factors showed three distinct clinical risk groups of tumours with different therapeutic outcomes.

INTERPRETATION

An integration of clinical risk factors and tumour molecular groups can be used to identify patients who are likely to have improved long-term radiation-free survival and might help therapeutic stratification of patients with atypical teratoid rhabdoid tumours.

FUNDING

C17 Research Network, Genome Canada, b.r.a.i.n.child, Mitchell Duckman, Tal Doron and Suri Boon foundations.

[Molecular subgrouping and characterization analysis of medulloblastomas in a cohort of Japanese patients]

Medulloblastoma is the most common solid malignancy and cause of oncologic death among children. Recent advances in genomic analysis obtained through international large-scale collaborations, Medulloblastoma Advanced Genomics International Consortium(MAGIC), have revealed that medulloblastomas can be classified into at least four distinct subgroups depending on their molecular expression profiles. These studies showed that the prognosis, age distributions, and molecular mechanisms of these subgroups of medulloblastomas completely differ from each other. Here we report the first analysis of molecular subgroups of medulloblastoma in Japanese patients(Shizuoka cohort). Molecular subgroups were predicted for 18 medulloblastomas;and age distributions, radiographic features, and histological characteristics were analyzed. It was predicted that 11% of the medulloblastomas were of the WNT type, 50% of the SHH type, 6% of the group 3 type, and 33% of the group 4 type. The percentage of group 3 type medulloblastomas was smaller than in the MAGIC study, while the percentage of the SHH type was larger. However, age distribution, recurrence-free survival, and overall survival for each group were quite similar to the MAGIC study. In addition, in an imaging study, 78% of patients with medulloblastomas of the SHH type presented tumors in the cerebellar hemispheres. The classical pathohistological hallmarks that may predict medulloblastoma prognosis were mainly seen in tumors of the SHH type. Molecular subgrouping of medulloblastomas could be important in the future, not only for prediction of prognosis, but also for decision making regarding the use of future new treatments such as molecular targeting therapy. The establishment of a public molecular analysis system of medulloblastomas in Japan is greatly desired, and it is currently under development;this database will help establish the molecular diagnosis of medulloblastomas in Japan.

Self-formation of functional adenohypophysis in three-dimensional culture

The adenohypophysis (anterior pituitary) is a major centre for systemic hormones. At present, no efficient stem-cell culture for its generation is available, partly because of insufficient knowledge about how the pituitary primordium (Rathke's pouch) is induced in the embryonic head ectoderm. Here we report efficient self-formation of three-dimensional adenohypophysis tissues in an aggregate culture of mouse embryonic stem (ES) cells. ES cells were stimulated to differentiate into non-neural head ectoderm and hypothalamic neuroectoderm in adjacent layers within the aggregate, and treated with hedgehog signalling. Self-organization of Rathke's-pouch-like three-dimensional structures occurred at the interface of these two epithelia, as seen in vivo, and various endocrine cells including corticotrophs and somatotrophs were subsequently produced. The corticotrophs efficiently secreted adrenocorticotropic hormone in response to corticotrophin releasing hormone and, when grafted in vivo, these cells rescued the systemic glucocorticoid level in hypopituitary mice. Thus, functional anterior pituitary tissue self-forms in ES cell culture, recapitulating local tissue interactions.

Self-organized formation of polarized cortical tissues from ESCs and its active manipulation by extrinsic signals

Here, we demonstrate self-organized formation of apico-basally polarized cortical tissues from ESCs using an efficient three-dimensional aggregation culture (SFEBq culture). The generated cortical neurons are functional, transplantable, and capable of forming proper long-range connections in vivo and in vitro. The regional identity of the generated pallial tissues can be selectively controlled (into olfactory bulb, rostral and caudal cortices, hem, and choroid plexus) by secreted patterning factors such as Fgf, Wnt, and BMP. In addition, the in vivo-mimicking birth order of distinct cortical neurons permits the selective generation of particular layer-specific neurons by timed induction of cell-cycle exit. Importantly, cortical tissues generated from mouse and human ESCs form a self-organized structure that includes four distinct zones (ventricular, early and late cortical-plate, and Cajal-Retzius cell zones) along the apico-basal direction. Thus, spatial and temporal aspects of early corticogenesis are recapitulated and can be manipulated in this ESC culture.

[Human pluripotent stem cell and neural differentiation]

Recovery of lost brain function is an important issue in medical studies because neurons of the central nervous system (CNS) have poor potential for regeneration. Since few CNS diseases can be treated completely by medicines, regenerative therapy by using stem cells should be studied as a new type of therapeutic intervention. The efficacy of cell replacement therapy in Parkinson's disease has been well investigated. Several studies on fetal tissue transplantation have revealed that quantity and purity of transplanted cells are necessary for recovery of symptoms. SFEB (Serum-free floating culture of embryoid body-like aggregates) method is capable of inducing multi-potential CNS progenitors that can be steered to differentiate into region-specific tissues. On the basis of the existing knowledge of embryology, we have succeeded in the generating of various types of neurons such as telencephalic, cerebeller (Purkinje and granule cells), retinal (photoreceptor cells) and hypothalamic neurons. Application of this culture method to human ES (hES) cells is necessary for clinical purpose: however, poor survival of hES cells in SFEB culture might limit the possibility of using these cells for future medical applications. We found that a selective Rho-associated kinase (ROCK) inhibitor, Y-27632, markedly diminished the dissociation-induced apoptosis of hES cells and enabled the cells to form aggregates in SFEB culture. For both mouse and human ES cells, SFEB culture is a favorable method that can generate large amounts of region-specific neurons. However, stem cell-based therapy continues to face several obstacles. It is important that researchers in the basic sciences and clinical medicine should discuss these problems together to overcome both scientific and ethical issues related to stem cells.

Toward the generation of rod and cone photoreceptors from mouse, monkey and human embryonic stem cells

We previously reported the differentiation of mouse embryonic stem (ES) cells into retinal progenitors. However, these progenitors rarely differentiate into photoreceptors unless they are cultured with embryonic retinal tissues. Here we show the in vitro generation of putative rod and cone photoreceptors from mouse, monkey and human ES cells by stepwise treatments under defined culture conditions, in the absence of retinal tissues. With mouse ES cells, Crx+ photoreceptor precursors were induced from Rx+ retinal progenitors by treatment with a Notch signal inhibitor. Further application of fibroblast growth factors, Shh, taurine and retinoic acid yielded a greater number of rhodopsin+ rod photoreceptors, in addition to default cone production. With monkey and human ES cells, feeder- and serum-free suspension culture combined with Wnt and Nodal inhibitors induced differentiation of Rx+ or Mitf+ retinal progenitors, which produced retinal pigment epithelial cells. Subsequent treatment with retinoic acid and taurine induced photoreceptor differentiation. These findings may facilitate the development of human ES cell-based transplantation therapies for retinal diseases.

A ROCK inhibitor permits survival of dissociated human embryonic stem cells

Poor survival of human embryonic stem (hES) cells after cell dissociation is an obstacle to research, hindering manipulations such as subcloning. Here we show that application of a selective Rho-associated kinase (ROCK) inhibitor, Y-27632, to hES cells markedly diminishes dissociation-induced apoptosis, increases cloning efficiency (from approximately 1% to approximately 27%) and facilitates subcloning after gene transfer. Furthermore, dissociated hES cells treated with Y-27632 are protected from apoptosis even in serum-free suspension (SFEB) culture and form floating aggregates. We demonstrate that the protective ability of Y-27632 enables SFEB-cultured hES cells to survive and differentiate into Bf1(+) cortical and basal telencephalic progenitors, as do SFEB-cultured mouse ES cells.

Mucocele in an Onodi cell responsible for acute optic neuropathy

An Onodi cell is defined as the most posterior ethmoid cell, which pneumatizes laterally and superiorly to the sphenoid sinus. A rare case of an isolated mucocele in an Onodi cell with unilateral acute visual disturbance is presented. MRI was imperative for the early and accurate diagnosis, and prompt surgical drainage resulted in dramatic visual recovery.

[Noninvasive carotid plaque characterization by black blood MRI]

Management of atherosclerotic carotid arteries requires both plaque characterization and determination of the degree of stenosis, especially when carotid stenting (CAS) is being considered for severe carotid stenosis. Recent studies have demonstrated that high-resolution MRI can identify plaque components, such as the lipid-rich necrotic core, intraplaque hemorrhage, fibrous tissue, and the calcification present in human carotid atherosclerosis. The purpose of this study was to assess the feasibility of black blood MRI (BB-MRI) for accurately identifying the plaque components in vivo. Twenty-six consecutive patients scheduled for carotid endarterectomy (CEA) underwent a BB-MRI examination within 2 weeks before the surgical procedure using a 1.5-T Philips scanner with a protocol that generated 2 contrast weightings (T1 and T2). The MR images were acquired using cardiac gating to minimize motion artifact and fat suppression to reduce MR signals from subcutaneous fatty tissue. The plaque evaluations obtained by BB-MRI were compared with the intra-operative video recordings, the excised specimens, and the histological sections. With BB-MRI, the combination of the signal intensities in the T1- and T2-weighted images for each component (lipid deposits, intra-plaque hemorrhage, fibrous plaque, and calcification) showed findings that corresponded with the excised specimens. Complex morphological features could also be assessed by BB-MRI. BB-MRI is a useful method for noninvasively imaging and characterizing atherosclerotic carotid arteries. This MRI technique can provide valuable information that can be used to decide whether to perform a CEA or a CAS in patients with severe carotid stenosis. Furthermore, BB-MRI appears to be a useful tool for the investigation of the pathogenesis and natural history of carotid atherosclerosis.

Surgical Clipping of a Recurrent Small Saccular Aneurysm After Repeated Coil Embolization-Case Report-

A 59-year-old healthy woman presented with sudden onset of severe headache. Computed tomography and digital subtraction angiography (DSA) demonstrated subarachnoid hemorrhage (grade I according to the Hunt and Hess classification) due to a ruptured small right posterior cerebral artery (PCA) aneurysm. The ruptured PCA aneurysm was completely embolized with three Guglielmi detachable coils (GDCs). However, follow-up DSA 3 months after the initial coiling confirmed refilling of the aneurysm. The aneurysm was successfully re-embolized with two GDCs. Follow-up DSA 10 months later revealed regrowth of the aneurysm. Surgical clipping was performed without compromising the parent vessels. Long-term angiographic follow up is necessary even in patients with small saccular aneurysms which are apparently completely embolized by endovascular coil treatment.

[Bilateral vertebral artery dissection and its chronological changes detected by MR angiography: a case report]

A case of intracranial bilateral vertebral artery (VA) dissection presenting with ischemic symptoms which following unilateral dissection is presented. A 42-year-old male with an occipital headache was pointed out right vertebral artery stenosis with magnetic resonance (MR) angiography 8 day before admission. He admitted to our hospital complaining of severe vertigo and tinnitus. MR images and cerebral angiograms revealed bilateral VA dissection with infarcts in light lower surface of cerebellum perfused by posterior inferior cerebellar artery and right hypothalamus. Conservative therapy was adopted and serial MR angiography was performed. His symptoms were improved gradually and MR angiograms obtained 2 months later revealed improvement of bilateral VA stenosis. It is generally accepted that VA dissection presenting ischemic symptoms has good outcome by conservative therapy only. However, its pathological process of progression is still unknown. Based on the serial MR findings, we discuss the mechanisms of bilateral VA dissection. In this case, we consider that unilateral VA dissection extended to contralateral vertebral artery through the vertebrobasilar junction. Frequent MR angiography in acute phase could be of great use for monitoring the progression of dissection.

[Fenestration of the extracranial internal carotid artery: report of two cases]

Fenestration of the internal carotid artery (ICA) is extremely rare on clinical settings. Six cases of fenestration in intracranial and 8 in extracracranial ICA have ever been reported in literature. Authors describe two cases of fenestration at the extracranial ICA that were initially suspected of the dissection of ICA on MRA/I. Both angiography and CT angiography (CTA) disclosed the fenestration, which located at C2 vertebral levels. To confirm the fenestration at extracranial ICA is important in such an occasion that mimic the dissection of ICA, especially in patients who complain of cervical pain, mass and other related symptoms. Differences in the fenestration, the dissection and atherosclerosis on imaging, were reviewed and discussed.

Reactive oxygen: its sources and significance in Alzheimer disease

Over the past decade, oxidative stress has been established as the earliest cytological feature of Alzheimer disease and an attractive therapeutic target. The major challenges now are establishing the source of the reactive oxygen and what oxidative stress tells us about the etiology of Alzheimer disease. These are complex issues since a variety of enzymatic and non-enzymatic processes are involved in reactive oxygen formation and damage to macromolecules. In this review, we consider disease mechanisms that show the greatest promise for future research.

High molecular weight neurofilament proteins are physiological substrates of adduction by the lipid peroxidation product hydroxynonenal

Protein adducts of the lipid peroxidation product trans-4-hydroxy-2-nonenal (HNE) are features of oxidative damage in neuronal cell bodies in Alzheimer's disease but are also seen in axons of normal as well as diseased individuals. In this study, focusing on the axons of the mouse sciatic nerve, we found that HNE adducts characterize axons of mice from birth to senility. Immunoblots of axonal proteins showed that HNE adducts are only detected in neurofilament heavy subunit (NFH) and, to a lesser extent, neurofilament medium subunit (NFM), both lysine-rich proteins, consistent with the adducts being limited to lysine residues. In vitro, HNE treatment of permeabilized sciatic nerve showed the same specificity, i.e. NFH and NFM are the only proteins that reacted with HNE, providing they are phosphorylated. Quantitative immunoblot analysis of two strains of mice ages 1-33 months showed that the levels of HNE adducts on NFH are consistent throughout life. Additionally, mice transgenic for human superoxide dismutase-1 with G85R mutation show no difference in HNE adduction to NFH compared with controls. Taken together, these studies indicate that HNE adduction to NFH is physiological, and its constancy from birth to senility as well as its dependence on phosphorylation argues that NFH and NFM modification may play a role in protecting the membrane-rich axon from toxic aldehydes resulting from oxidative damage.

Oxidative damage is the earliest event in Alzheimer disease

Recently, we demonstrated a significant increase of an oxidized nucleoside derived from RNA, 8-hydroxyguanosine (8OHG), and an oxidized amino acid, nitrotyrosine in vulnerable neurons of patients with Alzheimer disease (AD). To determine whether oxidative damage is an early- or end-stage event in the process of neurodegeneration in AD, we investigated the relationship between neuronal 8OHG and nitrotyrosine and histological and clinical variables, i.e. amyloid-beta (A beta) plaques and neurofibrillary tangles (NFT), as well as duration of dementia and apolipoprotein E (ApoE) genotype. Our findings show that oxidative damage is quantitatively greatest early in the disease and reduces with disease progression. Surprisingly, we found that increases in A beta deposition are associated with decreased oxidative damage. These relationships are more significant in ApoE epsilon4 carriers. Moreover, neurons with NFT show a 40%-56% decrease in relative 8OHG levels compared with neurons free of NFT. Our observations indicate that increased oxidative damage is an early event in AD that decreases with disease progression and lesion formation. These findings suggest that AD is associated with compensatory changes that reduce damage from reactive oxygen.

[Magnetic resonance imaging findings of postresuscitation encephalopathy: sequential change and correlation with clinical outcome]

OBJECTIVE

The purpose of this study was to describe the findings of sequential magnetic resonance imaging (MRI) in postresuscitation encephalopathy. Although its outcome is known to be overwhelming, but its acute findings by variable imaging methods are subtle and show only limited values. The correlation of the findings of MRI with clinical outcome were also analyzed.

METHODS

Twelve patients with global cerebral anoxia who underwent MRI with conventional and diffusion-weighted imaging were enrolled in this study. Compared with normal MRI images, abnormal signal regions were checked and described in cortex, basal ganglia and white matter. Also medical records were carefully reviewed to study the cause, the time necessary for resuscitation and long term clinical outcome.

RESULTS

The earliest finding was obtained by diffusion-weighted image less than 24 hours (acute period) in bilateral cerebral cortex as bright high signal intensity regions. Similar abnormality of bright high signal area in FLAIR and T 2 was followed according to the time elapsed in early subacute period (1-13 days). Succeedingly, white matter was involved and laminar necrosis in cortical area was observed in late subacute period (14-20 days). Finally, diffuse brain atrophy and obtundation of gray-white matter junction were seen in chronic stage (after 21 days). These MR findings were coincided well with histopathological findings reported in literatures. The poor outcome was closely and significantly correlated with abnormality in MR images.

CONCLUSION

MRI was a useful diagnostic modality to diagnose the whole brain ischemic encephalopathy and to predict the prognosis.

CI-ATPase and Na+/K(+)-ATPase activities in Alzheimer's disease brains

The enzyme activities and the protein levels of Cl(-)-ATPase and Na+/K(+)-ATPase were examined in Alzheimer's disease (AD) brains. Cl(-)-ATPase and Na+/K(+)-ATPase activities in AD brains (n = 13) were significantly lower than those in age-matched control brains (n = 12). In contrast, there was no significant difference in anion-insensitive Mg2(+)-ATPase activity between the two groups. Western blot analysis revealed that the protein levels of Cl(-)-ATPase, Na+/K(+)-ATPase and neuron specific Na+/K(+)-ATPase alpha3 isoform were also significantly reduced in AD brains, while the amount of protein disulfide isomerase, one of the house keeping membrane proteins, was not different between the two groups. The data first demonstrated that Cl(-)-ATPase and Na+/K(+)-ATPase are selectively impaired in AD brains, which may reduce the gradients of Na(+), K(+) and Cl(-) across the cell membranes to cause excitotoxic cellular response and the resulting neuronal death.

Optimization of a polarized photometric detector equipped with a split-type flow cell and its analytical application to oligo-saccharides

A novel, non-modulated polarimeter called a polarized photometric detector (PPD) was previously described by the authors. The PPD enables the measurement of the optical rotation of chiral compounds as a change in absorbance by placing two linear polarizers on either side of a flow cell of a conventional photometric detector. The present study describes the optimization of the conditions of PPD for highly sensitive detection of saccharides. To maximize the light intensity, the light balancing filter and slit were removed from the detector (Shimadzu model SPD-10AV). These modifications resulted in an approximately 15-fold increase in the incident light intensity when the maximum current was applied to the lamp. When this intense light was transmitted through the polarizers, the signal intensity followed the theoretical equation for phase angles up to around 1 rad. If the energy of the transmitted light was less than 700 mV, however, the baseline noise was too great to determine the chiral analyte accurately. Setting the phase angle between two polarizers at 50 degrees and the detection wavelength at 400 nm provided the most suitable conditions. This detector was applicable for the determinations of oligosaccharides in foodstuffs separated by HPLC using gradient elution.

Malignant pleomorphic adenoma (malignant mixed tumor) of the trachea. Report of a case

Malignant pleomorphic adenoma arising in the trachea has not been reported in the literature. We report here a case of malignant pleomorphic adenoma (malignant mixed tumor) occurring in the trachea of a 65-year-old woman. The tumor metastasized to the lung and the chest wall 11 years after complete resection of the primary tumor, which was a polypoid submucosal tumor, 1.3 cm in diameter. Light microscopic examination of the primary and metastatic tumors showed the presence of epithelial and stromal elements, consisting of grandular structures, foci of squamous metaplasia and a myxochondroid stroma. Many tumor cells showed myoepithelial cell features by electron microscopy, and immunoreactivity for S-100 protein and GFAP was also seen in many of them. These findings were consistent with those of pleomorphic adenoma. However, the epithelial elements were cytologically atypical with prominent mitotic figures. Infiltration of the tumor cells into the surrounding soft tissue was also seen. No foci of benign pleomorphic adenoma were found in the primary tumor. These findings indicate that this tumor was not a carcinoma ex pleomorphic adenoma, but a true malignant pleomorphic adenoma (true malignant mixed tumor) of the trachea.

Neurothekeoma. Report of a case with immunohistochemical and ultrastructural studies

A case of neurothekeoma in a 52-year-old woman is reported. The tumor developed on the medial aspect of the right nostril as a well-demarcated, dome-shaped, erythematous nodule of rubbery consistency. Microscopically, it consisted of numerous nests and cords of spindle-shaped cells in the dermis. Some of the tumor cell nests appeared epithelial-like, while the other areas showed a myxomatous appearence with various amount of mucinous matrix in the intercellular space. Neurothekeoma is a benign cutaneous tumor, and is considered to be of schwann cell origin. In the present case, the tumor cells did not stain positively for S-100 protein, despite the light microscopic suggestion of peripheral nerve origin. Ultrastructurally, most tumor cells contained a large number of myelinoid figures. This ultrastructural finding appears to be a useful diagnostic characteristics of neurothekeomas.