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The effect of the volume fraction of 3D-metal matrix composites (MMC) framework on the compressive properties of 3D interpenetrating hierarchical ZrO2-toughened Al2O3 particle (ZTAp)/40Cr steel composites was investigated. The results showed that the compressive properties of the material tended to decrease as the volume fraction of 3D-MMC framework increased. The composite with 35 vol.% 3D-MMC had a yield strength of 1455.2 MPa and compressive strength of 1612.8 MPa, which occurred at a strain value of 5.6%. Compared to the homogeneously dispersed composite material, the composite with 35 vol.% 3D-MMC had a 144.7% higher yield strength, which occurred at a 20% higher strain. An analysis of the cracks inside the material revealed that the crack was hindered and deflected by the matrix during propagation, which lengthened the crack propagation path and consumed more energy, thus leading to toughening. The results indicated that 3D interpenetrating hierarchical structure had a strengthening and toughening effect on ZTAp/40Cr composites.

Primary tumors of the spinal cord are rare, accounting for 3-6% of tumors in the central nervous system, particularly in children. KIAA1549-BRAF fusion is more common in pilocytic astrocytoma (PA) and IDH1 R132H mutation is rare in infratentorial tumors. Here, we report a 10-year-old male patient who presented with weakness in lower limbs that progressed to difficulty walking. Magnetic resonance imaging (MRI) revealed an intramedullary solid-cystic lesion from the medulla oblongata to the thoracic spin 4 level, with the expansion of the spinal cord. The lesion exhibited patchy enhancement at C4-T1, indicating a tentative diagnosis of astrocytoma. The patient underwent resection of the lesion in the spinal canal from the cervical 6 level to the thoracic 2 level. Histopathology confirmed diagnosis of astrocytoma, WHO grade 2. Genetic analysis showed both IDH1 R132H mutation and KIAA1549-BRAF fusion. Therefore, our integrated diagnosis was astrocytoma, IDH mutation, WHO grade 2. Its molecular analyses include IDH1 R132H mutation and KIAA1549-BRAF fusion. After the operation, the patient did not receive chemo- or radiotherapy, and underwent an aggressive rehabilitation regiment. Follow up 10 months later, symptoms improved. To our best knowledge, this is the first case of concomitant IDH mutation and BRAF fusion in pediatric spinal cord astrocytoma.

Cartilaginous metaplasia is rare in primary central nervous system (CNS) neoplasms and has not been described in the histone 3 (H3) gene (H3) with a substitution of lysine to methionine (H3 K27M mutant) diffuse midline glioma before. Here, we report a case of H3 K27M mutant diffuse midline glioma with cartilaginous metaplasia in a 56-year-old woman. Magnetic resonance imaging (MRI) revealed a ring-enhanced lesion located in the medulla oblongata and extended superiorly into the fourth ventricle. The tumor was macroscopically completely resected. Histologically, the tumor was composed of a gliomatous component and a well-differentiated cartilaginous component. Microvascular proliferation and necrosis were noted. According to immunohistochemical staining, glial cells were diffusely and strongly positive for glial fibrillary acidic protein (GFAP), oligodendrocyte lineage transcription factor 2 (Olig2), H3 K27M, and S-100 protein but negative for H3K27me3. The chondrocytes also were positive for GFAP and S-100 protein. The H3 K27M mutation was confirmed by sequencing in both the gliomatous and cartilaginous components, suggesting a common origin from the same progenitor cells. Based on these findings, the tumor was diagnosed as a diffuse midline glioma with H3 K27M mutation with widespread cartilaginous metaplasia, corresponding to WHO grade IV. This is an extremely rare H3 K27M mutant diffuse midline glioma with cartilaginous metaplasia, and reporting this unusual case adds to the understanding of this tumor type.

The n-type hexagonal (Bi(Bi2S3)9)I3)0.667 compound was synthesized by a facile process, a hydrothermal method combined with spark plasma sintering. The thermoelectric properties of the (Bi(Bi2S3)9)I3)0.667 bulk sample were investigated in detail. The results show that a peak ZT value of 0.04 was obtained at 673 K along the perpendicular pressure direction.

The characteristics of H3.3 G34-mutant gliomas in adults have yet to be specifically described. Thirty adults with H3.3 G34-mutant diffuse gliomas were retrospectively reviewed for clinical and pathologic information. Molecular profiling using next-generation sequencing was performed in 29 of the 30 H3.3 G34-mutant patients with 1 patient lacking available tumor samples, as well as 82 IDH/H3 wild-type adult diffuse glioma patients. The age at diagnosis of H3.3 G34-mutant diffuse gliomas was significantly younger than IDH/H3 wild-type gliomas (24 vs. 57 y, P

Bi2S3, with earth-abundant compositions and a low thermal conductivity, is regarded as a candidate thermoelectric material. In this work, Bi2S3 samples that were doped with x % mol InCl3 were successfully fabricated via a mechanical alloying and spark plasma sintering process. InCl3, as an n-type donor dopant, was added to the Bi2S3 system to improve its electrical transport properties and optimize its thermal conductivity. Upon doping, the electrical conductivity of Bi2S3 doped with 1 mol% InCl3 reaches up to 62 Scm−1, and the Seebeck coefficient maintains a relatively large value of −244 μV K−1 at 673 K, which results in a maximum power factor of 363 μW m−1 K−2. Furthermore, due to a simultaneously reduced thermal conductivity at high temperature, a ZT peak of 0.57 is obtained at 673 K along the parallel to the press direction for the sample doped with 1.0 mol% InCl3, which is almost four times higher than that of pristine Bi2S3 (0.14 at 673 K). The elastic properties and Debye temperature of Bi2S3 are also calculated to analyze the origin of the intrinsically low thermal conductivity and are compared to those of other thermoelectric materials with a low thermal conductivity.

Aims To evaluate the occurrence and diagnostic value of MYB-QKI rearrangement status in angiocentric glioma (AG) in Chinese patients. Materials and methods 27 cases were collected from six hospitals, followed by a retrospective analysis of clinical, radiological, and morphological data. MYB protein expression was assessed by immunohistochemical staining (IHC), and the MYB-QKI rearrangement was detected by fluorescence in situ hybridization (FISH). Results Among the 27 cases (16 males), the median age at surgery was 17 years (range 3 - 43 years); 24 (88.9%) cases had a history of refractory epilepsy, and the mean history of pre-surgical epilepsy was 13 years (range 1.5 - 27 years); 26 (96.3%) cases had lesions located in the superficial cerebrocortical regions, and 1 (3.7%) case had a lesion in the brainstem. Except for the classic histological features, the involvement of superficial cortex extending to the leptomeninges, microcalcification, and cystic pattern with microcystic formations was observed in 11 (40.7%), 3 (11.1%), and 4 (14.8%) cases, respectively. IHC showed that all 27 cases were positive for glial fibrillary acidic protein (GFAP) and vimentin, and negative for neuronal nuclear antigen (NeuN). The positive rates of epithelial membrane antigen (EMA) and D2-40 were 81.5% (22/27) and 74.1% (20/27), respectively. A total of 14 (51.9%) cases were positive for MYB. The rate of Ki-67 proliferation was 1 - 5% in 25 cases, and in 2 cases with anaplastic features it was 10 and 20%. MYB-QKI rearrangement was revealed by FISH examination in 95.8% (23/24) of the AGs, including 3 cases with atypical histological appearance. Conclusion Compared to IHC, FISH was more appropriate for detecting MYB-QKI rearrangement. MYB-QKI rearrangement was detected in the majority of Chinese AG cases, and therefore represents a potential diagnostic biomarker for AG.

The n-type hexagonal (Bi(Bi

MGMT promoter methylation is considered as a prognostic and predictive biomarker indicating response to chemotherapy and radiotherapy in glioblastoma. A number of different methods and platforms including pyrosequencing (PSQ), quantitative methylation-specific PCR (qMSP) and immunohistochemistry (IHC), methylation-sensitive high resolution melting (MS-HRM) and NGS (Next Generation Sequencing) have been used to detect MGMT promoter methylation in gliomas. However, controversy remains about the most appropriate method to use for analyzing MGMT status. The MGMT promoter methylation status of a total of 350 gliomas and gangliogliomas was examined using PSQ, qMSP and IHC in parallel. Using PSQ as a recommended standard method, the sensitivity, specificity, positive/negative predictive value and correlation with the other assays were calculated. Among 350 glioma and ganglioglioma cases, the MGMT promoter tested positive for methylation in 53.1%, 55.4%, and 70.3% of the cases by PSQ, qMSP and IHC, respectively. The sensitivity and specificity of qMSP were 97.8% and 92.7%, respectively. Twelve cases that tested positive for methylation using qMSP were negative according to PSQ, and four cases that were negative according to qMSP tested positive according to PSQ. The concordance rate between PSQ and qMSP was 90.8%. The sensitivity and specificity of IHC for the detection of MGMT at the protein level were 84.4% and 45.7%, respectively. The concordance rate between PSQ and IHC was 30.8%. This study demonstrated that qMSP is an effective and rapid detection method for routine use in pathology laboratories for the identification of MGMT promoter methylation. A combination of IHC and qMSP assays can provide high sensitivity and specificity for the prediction of MGMT status. A few cases that tested negative with PSQ did harbor MGMT promoter methylation, as confirmed by qMSP and sequencing, and this subgroup of patients may benefit from temozolomide.

OBJECTIVE In 2011, the International League Against Epilepsy (ILAE) proposed a consensus classification system of focal cortical dysplasia (FCD) to distinguish clinicopathological subtypes, for example, "isolated" FCD type Ia-c and IIa-b, versus "associated" FCD type IIIa-d. The histopathological differentiation of FCD type I and III variants remains, however, a challenging issue in everyday practice. We present a unique histopathological pattern in patients with difficult-to-diagnose FCD, which highlights this dilemma, but also helps to refine the current ILAE classification scheme of FCD. METHODS We present a retrospective series of 11 male and one female patient with early onset pharmacoresistant epilepsy of the posterior quadrant (mean age at seizure onset = 4.6 years). All surgical specimens were reviewed. Clinical histories were retrieved and extracted from archival patient files. RESULTS Microscopic inspection revealed abnormalities in cortical architecture with complete loss of layer 4 in all surgical samples of the occipital lobe, as confirmed by semiquantitative measurements (p < 0.01). Clinical history reported early transient hypoxic condition in nine patients (75%). Magnetic resonance imaging (MRI) revealed abnormal signals in the occipital lobe in all patients, and signal changes suggestive of subcortical encephalomalacia were found in seven patients. Surgical treatment achieved favorable seizure control (Engel class I and II) in seven patients with an available follow-up period of 6.1 years. SIGNIFICANCE Prominent disorganization of cortical layering and lack of any other microscopically visible principle lesion in the surgical specimen would result in this neuropathological pattern hitherto being classified as FCD ILAE type Ib. However, perinatal hypoxia with distinctive MRI changes suggested primarily a hypoxemic lesion and acquired pathomechanism of neuronal cell loss in the occipital lobe of our patient series. We propose, therefore, classifying this distinctive clinicopathological pattern as a separate variant of FCD ILAE type IIId.

Gliosarcoma, which is regarded as a variant of glioblastoma, is a rare malignant neoplasm of the central nervous system. Both its sarcomatous component and glial component are reported to share significant clinical and genetic similarities. However, gliosarcomas are considered to be characterised by a lack of the BRAF V600E mutation. Here, we report two cases of gliosarcoma harbouring the BRAF V600E mutation, of which one case appears to have arisen de novo, while the other likely arose from ganglioglioma. Interestingly, the BRAF V600E mutation was detected only in the glial component in the first case, but was present in both the glial and the sarcomatous components in the recurrent gliosarcoma. Furthermore, the different mutation state of BRAF V600E in our two cases suggests that the malignant transformation of gliosarcoma might have different underlying genetic alterations and mechanisms in de novo versus recurrent gliosarcoma.

ETS-related gene (ERG) is an oncogene that is commonly found in prostate cancer (PCa). Several miRNAs have been reported to be associated with PCa. This study was undertaken to identify miRNAs that act as a tumor suppressor by targeting ERG. We collected 70 PCa and paired adjacent non-tumor (Adjacent-N) tissues and analyzed ERG expression by immunohistochemistry(IHC). Expression of 6 miRNAs (miR-21,-34a,-96,-125b,-150 and miR-1271) was analyzed by qRT-PCR. Luciferase reporter assay was performed to examine miRNA binding to the 3′-UTR of target genes. The effects of ectopic expression of miRNA on cell growth and MAPK signaling pathway were investigated in in PC-3 and LNCaP cell lines. Among 70 PCa cases, 13 (18.6%) were ERG positive. No significant difference of miR-34a, 96, 125b, and 150 expression was found between PCa and Adjacent-N tissues. Significantly higher level of miR-21 and lower level of miR-1271 expression were found in cancer tissues. Furthermore, miR-1271 was down-regulated in ERG-positive PCa cases (p

The effect of the hardness of a steel matrix by heat treatment on the impact abrasive wear of ZTAp/40Cr steel architecture composites is investigated. Of these composites, the ZTA particles-reinforced 40Cr steel matrix composite and pure 40Cr steel formed a 3D network interpenetrating structure. The results show that the architecture composites with the martensite matrix demonstrate the best wear resistance, which is 32.76% higher than that with the troostite matrix and 163.60% higher than that with the pearlite matrix. Under the same Under the same quenching + 460 °C tempering conditions, the wear resistance of the architecture composites is 79.0% higher than that of the homogeneous composites. The wear mechanism analysis shows that the wear performance of composites depends on the interaction between the matrix and the reinforced particles. As the hardness of the composites matrix increases, the reinforcement particles are more strongly supported by the matrix. Conversely, the matrix is preferentially worn, and the ZTA particles are shed due to the lack of protection. The main wear mechanisms include micro-cutting, plastic fatigue wear, and particle crushing and spalling.

Background and Aim: Mutations in isocitrate dehydrogenase (IDH), co-deletion of 1p and 19q, loss or expression of the transcription regulator ATRX, and mutations in telomerase reverse transcriptase (TERT) gene promoters are intimately linked with diffuse gliomas. We further explored the roles of the key molecules in adulthood diffuse gliomas and their prognosis. Materials and Methods: A total of 413 patients who underwent primary surgery between 2009 and 2015 at Xuanwu Hospital, Beijing, China, were included in this observational study. All specimens from the patients were fixed in 10% neutral buffered formalin and embedded in paraffin. The mutational status of IDH1/2 and the TERT promoter was determined using polymerase chain reaction-based direct sequencing. The assay for the 1p and 19q co-deletion was conducted using fluorescence in situ hybridization. Overall- and progression-free survival was calculated using the Kaplan–Meier method and the log-rank test. The study was approved by the Ethics Committee of Xuanwu Hospital, Capital Medical University, China (approval No. [2019]004) on May 22, 2019. Results: We found that tumors characterized by multiple lesions were predominantly free of IDH mutations (P < 0.001). Gliomas with IDH mutations arose more often in the frontal and insular lobes than in the other lobes (P < 0.001). Rates of IDH mutations were higher in patients who had seizures or were without discomfort than in those who had other clinical symptoms (P = 0.0003). Of 119 patients with complete molecular information according to the 2016 World Health Organization classification of central nervous system tumors, 5 had oligoastrocytomas that had multiple genotypes – IDH1 mutation, loss of ATRX expression, and 1p/19q co-deletion – but lacked TERT promoter mutations. Patients with seizures or without discomfort who had IDH mutations had better outcomes than did other patients (P < 0.001). Patients whose tumors had IDH and TERT promoter mutations had a better prognosis than did other patients (P < 0.001). Among patients whose tumors had wild-type IDH, those with loss of ATRX survived longer than did others (P = 0.005). Conclusions: The status of both ATRX and the TERT promoter can indicate the prognosis in patients with IDH wild-type gliomas. The diagnosis that is based on clinical symptoms, histologic findings, and molecular analysis should be implemented as the diagnostic standard for patients with oligoastrocytomas.

The histone H3 K27M mutation has been frequently reported in most diffuse midline gliomas. However, the relationship between the H3 K27M mutation and clinical outcomes of gliomas from different anatomical locations is still not fully understood. A total of 120 patients with diffuse midline gliomas were selected for this retrospective observational study. The status of H3 K27M, ATRX, TP53, and IDH was evaluated using immunohistochemistry and Sanger sequencing. Of the 120 patients aged from 4 to 76 years (median, 27 years), 61 (50.8%) were harboring the H3 K27M mutation. Tumors were mainly located in the brainstem, ATRX thalamus, and spinal cord, but also in the cerebellum, corpus callosum, and the lateral ventricle. Patients with H3 K27M-mutant diffuse midline gliomas had a significantly shorter overall survival than H3 wild-type counterparts (P = .001). However, the H3 K27M mutation was mainly associated with a poorer prognosis in infratentorial gliomas compared with the corresponding H3 wild-type gliomas (P < .0001), but not in supratentorial gliomas (P = .603). Moreover, patients with H3 K27M-mutant gliomas in unusual anatomical locations had a better prognosis than did those with corresponding tumors in the brainstem. This study may provide guidance for better treatment stratification decisions for diffuse gliomas bearing the H3 K27M mutation, which arise in different locations of the brainstem, thalamus, spinal cord, or other sites.

Background Stimulation of the anterior nucleus of the thalamus (ANT) is effective in seizure reduction, but the mechanisms underlying the beneficial effects of ANT stimulation are unclear. Objective To assess the beneficial effects of ANT stimulation on hippocampal neurons of epileptic monkeys. Methods Chronic ANT stimulation was applied to kainic acid-induced epileptic monkeys. Behavioral seizures were continuously monitored. Immunohistochemical staining and western blot assays were performed to assess the hippocampal injury and the effects of ANT stimulation. Results The frequency of seizures was 42.8% lower in the stimulation group compared with the sham-stimulation group. Immunohistochemical staining and western blot analyses indicated that neuronal loss and apoptosis were less severe and that neurofilament synthesis was enhanced in the stimulation monkeys compared with the sham-stimulation group. These data showed that the hippocampal injury was less severe in monkeys in the stimulation group than in those in the sham-stimulation group. Conclusions Our data suggest that chronic ANT stimulation may exert protective effects on hippocampal neurons and boost the regeneration of neuronal fibers. These effects may be closely related to the mechanisms of ANT stimulation in epilepsy treatment.

Aims Angiocentric glioma (AG) is a rare, slow-growing tumour of the central nervous system. It is often associated with refractory epilepsy and occurs most commonly in children and young adults. We herein report nine cases of AG, including four with atypical histological findings. Methods The clinical data and clinicopathological findings of nine cases with AG histological features were described. Results All nine patients had a history of refractory epilepsy with a mean history of 4.4 years and a median age of 17.6 years at surgery. The AG lesions were located in the superficial cerebrocortical region. Histological examination of these cases revealed characteristic structural features of AG, including bipolar spindle-shaped cells with an angiocentric growth pattern. However, four cases also exhibited atypical histological features: one had astroblastoma-like characteristics, two had a distinct cystic region with an onion-like structure and myxoid changes, and the other one had a region involving many abnormal neurones reminiscent to ganglioglioma. All were positive for glial fibrillary acidic protein and vimentin. Eight cases were positive for epithelial membrane antigen (EMA), with a dot-like staining pattern. A diffuse D2-40 staining was visible in these cases, with two having similar staining pattern to EMA. All cases were immunonegative for BRAF V600E and isocitrate dehydrogenase-1 R132H mutations. Conclusions Our results demonstrate that atypical histological features can be present in AG. A collection of more cases and further molecular analyses are required to confirm our findings.

Sturge-Weber syndrome (SWS) is a rare syndrome characterized by capillary-venous malformations involving skin and brain. Many patients with SWS also suffer from drug-resistant epilepsy. We retrospectively studied a series of six SWS patients with epilepsy and extensive neurosurgical resections. At time of surgery, the patients' age ranged from 11 to 35 years (with a mean of 20.2 years). All surgical specimens were well preserved, which allowed a systematic microscopical inspection utilizing the 2011 ILAE classification for focal cortical dysplasia (FCD). Neuropathology revealed dysmorphic-like neurons with hypertrophic cell bodies reminiscent to those described for FCD type IIa in all cases. However, gross architectural abnormalities of neocortical layering typical for FCD type IIa were missing, and we propose to classify this pattern as FCD ILAE type IIIc. In addition, our patients with earliest seizure onset also showed polymicrogyria (PMG; n = 4). The ictal onset zones were identified in all patients by subdural electrodes, and these areas always showed histopathological evidence for FCD type IIIc. Four out of five patients had favorable seizure control after surgery with a mean follow-up period of 1.7 years. We concluded from our study that FCD type IIIc and PMG are frequently associated findings in SWS. FCD type IIIc may play a major epileptogenic role in SWS and complete resection of the associated FCD should be considered a prognostic key factor to achieve seizure control.

This research randomly selected 362 households from 20 villages in Shaanxi Province to study the villager satisfaction with village committee. It divided the factors hypothesized to influence the satisfaction degree with village committee into three categories based on the method of factor analysis and applied logistic regression model to conduct empirical analysis. The result shows that influences including disclosure of village affairs and finance, fairness of village affairs, democratically-managed major events, democratic election, satisfaction with village cadres, satisfaction with the public services of education, roads, electric power, science and technology, hygiene and medical care provided by village committee have significant impacts on the satisfaction evaluation of the village committee. In addition, villagers gender and the status of village cadres also affect the satisfaction evaluation of the village committee. Further, the effect of the factors above has an important characteristic in order and phase.

Chordoid glioma is a rare, slowly growing tumor of the CNS, which is always located in the third ventricle of adults. Chordoid glioma has classic histological features consisting of clusters and cords of epithelioid tumor cells embedded within a mucinous stroma with rich lymphoplasmacytic infiltrate. The important distinctive immunohistochemical feature of this neoplasm is strong and diffuse reactivity for GFAP. Here, we report four cases of chordoid glioma that occupied the anterior portion of the third ventricle or suprasellar region. These four cases were all adult females with almost typical clinical, radiological, histologic and immunohistochemical characteristics of chordoid glioma. However, in one case there was an unusual histologic finding with regard to the papillary region. In this region, elongated tumor cells were observed radiating toward a central vessel to form characteristic papillary structures. Immunohistochemically, three cases showed strong reactivity for GFAP, and one exhibited weak reactivity. All cases were focally positive for epithelial membrane antigen, CD34 and D2-40, but negative for neurofilament protein (NFP). Several ultrastructural investigations have supported the ependymal origin of chordoid glioma. In some cases of immunoreactivity for NFP, some authors have supposed that chordoid glioma originates from a multipotential stem cell with glial and neuronal cell differentiation. With regard to the present four cases with immunoreactivity for D2-40 (an ependymal marker) and CD34 (undifferentiated neural precursors) and based on previously published data, we considered that the majority of chordoid gliomas had an ependymal origin, and that a small minority might have originated from a multipotential stem cell having ependymal and neuronal cell differentiation.