Central nervous system dissemination in spinal cord astrocytomas: association with H3 K27M mutation.

OBJECTIVE: Patients with spinal cord astrocytomas (SCAs) are at high risk for CNS dissemination, yet comprehensive data on characteristics of dissemination are lacking. This study depicts the exact incidence and patterns of dissemination by analyzing data from a large-scale dataset of SCA. METHODS: The authors included 94 patients with SCA based on the 2021 WHO classification from 2011 to 2022, retrospectively collected their clinical and pathological characteristics, and analyzed factors influencing SCA dissemination. RESULTS: CNS dissemination, encompassing leptomeningeal spreading and/or subarachnoid seeding, was evaluated in 94 patients with and without H3 K27 alterations, with an overall dissemination rate reaching 85.0% at 5-year follow-up. Patients with altered H3 K27 had a significantly higher 5-year CNS dissemination rate than patients with H3 K27 wildtype status (95.2% vs 68.0%, p = 0.002). The median dissemination-free survival in H3 K27-altered patients was 14.37 (95% CI 2.84-25.89) months, significantly shorter than those with H3 K27 wildtype (statistics not calculated; p < 0.001). Based on univariate Cox regression analysis, H3 K27M alteration, higher histopathological grade, Ki-67 index (≥ 10%), and tumor length (≥ 4 segments) were identified as potential factors associated with CNS dissemination in SCAs. Multivariate Cox regression analysis revealed that H3 K27M alteration appeared to be a risk factor for this phenomenon (HR 2.089, 95% CI 0.940-4.642, p = 0.070). Following dissemination, H3 K27-altered patients had a median postdissemination survival of 8.83 (95% CI 7.13-10.54) months, which was significantly shorter than the 13.40 (95% CI 3.98-34.26) months in those with H3 K27 wildtype (p = 0.008). CONCLUSIONS: Factors indicative of higher SCA malignancy, such as H3 K27M alteration, higher histopathological grade, Ki-67 index (≥ 10%), and tumor length (≥ 4 segments), were similarly suggestive of higher rates of dissemination. The occurrence of dissemination is closely associated with the outcome events in patients with SCA.

Peer feedback and Chinese medical students' English academic writing development: a longitudinal intervention study.

BACKGROUND: Studies have documented that utilizing peer feedback can enhance students' English academic writing skills. Little is known, however, about the effects of incorporating peer feedback to enhance English as a second language (L2) medical students' academic writing performance. METHODS: This longitudinal interventional study examines Chinese medical students' English academic writing skills development via peer feedback in four parallel classes over an 18-week semester between the experimental and control groups (n = 124). RESULTS: Significant increases in the experimental group's performance in the post-test were found after 18-week instructions (pre- vs. post-test: overall score, p < .001; task response, p < .001; coherence and cohesion, p < .001; lexical resource, p < .001; grammatical range and accuracy, p < .001), and the effects were retained in the delayed post-test 6 weeks later (post- vs. delayed post-test: overall score, p = .561; task response, p = .585; coherence and cohesion, p = .533; lexical resource, p = .796; grammatical range and accuracy, p = .670). Little improvement was found in the control group in the post-test (pre- vs. post-test: overall score, p = .213; task response, p = .275; coherence and cohesion, p = .383; lexical resource, p = .367; grammatical range and accuracy, p = .180) or the delayed post-test (post- vs. delayed post-test: overall score, p = .835; task response, p = .742; coherence and cohesion, p = .901; lexical resource, p = .897; grammatical range and accuracy, p = .695). Between-group comparisons indicate that the experimental group outperformed the control group in the post- and the delayed post-tests, as shown in their overall score and scores on the four components. CONCLUSIONS: Incorporating peer feedback into process-oriented medical English writing classroom teaching can effectively enhance Chinese medical students' English academic writing skills over time, while the traditional product-oriented writing instructions had little help in improving Chinese medical students' academic writing skills. This longitudinal intervention study develops our understanding of the effectiveness of peer feedback in L2 academic writing pedagogy. It offers instructional implications for L2 writing teachers to teach English academic writing among medical students in China and beyond. Limitations and suggestions for future studies are discussed.

Long-term outcome and prognostic factors of syringo-subarachnoid shunt for syringomyelia.

BACKGROUND: Syringo-subarachnoid shunt (SSS) is often considered a rescue procedure or a second-line treatment option for syringomyelia. However, the clinical efficacy of SSS in treating this condition remains controversial. OBJECTIVE: To evaluate the long-term outcome of the SSS and its relationship with the syrinx area, as well as to investigate the factors that influence the prognosis. METHODS: This retrospective study included twenty-seven consecutive patients who underwent SSS between 2014 and 2020. The study evaluated several independent variables such as age, sex, duration of progressive symptoms, morphological characteristics of the syrinx, changes in the syrinx area, and Chiari malformation. The long-term follow-up (>2 years) Japanese Orthopaedic Association (JOA) score was used to assess neurological function and outcome. Statistical analysis was performed using a stepwise logistic regression test. RESULTS: All patients were followed up for an average of 48.6 ± 14.8(26.8 to 78.0) months. Follow-up magnetic resonance imaging showed syrinx collapse to different degrees occurred in 96.3% (26 of 27) patients. The JOA score was improvedinonly6patients (22.2%), remained stable in 5 patients (18.5%),and deteriorated in 16 patients(59.3%).A logistic regression test showed that the tension syrinx (odds ratio 0.111) and early shunting intervention (odds ratio 0.138) were favorable independent prognostic factors. CONCLUSIONS: It is important to note that the shrinkage of the syrinx does not necessarily translate to an improvement in clinical outcomes. Therefore, the decision to perform SSS should be made with caution and considered as a last resort.

Clinical management and prognosis of spinal myxopapillary ependymoma: a single-institution cohort of 72 patients.

PURPOSE: Myxopapillary ependymoma (MPE) was classified as grade 2 tumor in the 2021 World Health Organization central nervous system classification because of its high recurrence probability. This study aimed to investigate predictive factors and management of tumor recurrence. METHODS: Seventy-two patients with spinal MPE underwent initial surgical treatment at our hospital between 2011 and 2021. Kaplan-Meier curves and Cox regression were used to analyze the correlation between clinical variables and progression-free survival (PFS). RESULTS: The median age at diagnosis was 33.5 years (range 8-60 years). Twenty-one patients (29.2%) had preoperative spinal drop metastases. Gross total resection (GTR) was performed in 37 patients (51.4%). The median follow-up was 7.2 years, and the follow-up rate was 88.9% (64 of 72 cases). Twelve of the 64 patients (18.9%) relapsed, and preoperative drop metastasis occurred in 7 patients (58.3%). The estimated 5-year and 10-year PFS rates were 82% and 77%, respectively. Univariate analysis showed that GTR was associated with improved PFS (hazard ratio [HR] 0.149, p = 0.014), while preoperative drop metastasis (HR 3.648, p = 0.027) and tumor involvement sacrococcygeal region (HR 7.563, p = 0.003) were associated with tumor recurrence. Adjuvant radiotherapy (RT) was significantly associated with improved PFS in patients with preoperative drop metastasis (p = 0.039). CONCLUSION: Complete surgical resection under the premise of protecting neurological function is an important factor in reducing spinal MPE recurrence. Adjuvant RT is recommended when the tumor invades the capsule with preoperative drop metastasis or adhesion to the nerve and cannot reach GTR.

Intramedullary spinal cavernous malformations with high ossification: a case report and review of the literature.

BACKGROUND: Cavernous malformations of the spinal cord are a rare type of vascular malformation, comprising approximately 5 to 16% of all vascular lesions in the spinal cord. Depending on their origin position, these malformations can be distributed in different locations within the spinal canal. Although intramedullary cavernous malformations have been reported in the literature, they are exceedingly rare. Furthermore, highly calcified or ossified intramedullary cavernous spinal malformations are even rarer. CASE PRESENTATION: Here, we present a case report of a 28-year-old woman diagnosed with a thoracic intramedullary cavernous malformation. The patient had been experiencing progressive numbness in her distal limbs for a period of 2 months. During routine lung computed tomography screening for COVID-19, a hyperdense mass was noted in the patient's spinal canal. Magnetic resonance imaging revealed a mulberry-shaped intramedullary mass at the T1-2 level. The patient underwent surgical treatment, during which the entire lesion was successfully removed, resulting in a gradual improvement of her symptoms. Histological examination confirmed the presence of cavernous malformations with calcification. CONCLUSIONS: Intramedullary cavernous malformations with calcification are rare and special type that should be treated surgically in the early stage without significant neurological impairment before rebleeding or enlargement of the lesion can occur.

Long-term outcomes of foramen magnum decompression with duraplasty for Chiari malformation type I in adults: a series of 297 patients.

OBJECTIVE: Foramen magnum decompression with duraplasty (FMDD) is one of the most frequently utilized surgical treatments for Chiari malformation type I (CMI) in adults. However, its long-term outcomes remain controversial. The object of this study was to evaluate the long-term outcomes of FMDD in adults with CMI. METHODS: In total, 297 adults with CMI who had undergone FMDD at the authors' institution between 2011 and 2020 were included in this retrospective study. Long-term (> 1 year) outcomes were evaluated using the Chicago Chiari Outcome Scale (CCOS), visual analog scale (VAS), and Japanese Orthopaedic Association (JOA) scale. RESULTS: The median patient age was 44 years (range 18-65 years). The mean clinical follow-up period was 67 months (range 14-123 months). Compared with preoperative conditions, the postoperative syringomyelia regression rate was 91.3% (242/265), and the cerebellar tonsil ascended in 18.2% of patients (54/297), was stable in 64.3% (191/297), and continuously descended in 17.5% (52/297). Long-term clinical follow-up data were acquired from 267 patients. According to the CCOS score, the patient's condition improved in 62.5% of cases (167/267), was stable in 31.8% (85/267), and worsened in 5.6% (15/267). According to the VAS score, the patient's condition improved in 59.5% of cases (110/185), remained unchanged in 27.6% (51/185), and worsened in 13.0% (24/185) among the follow-up patients with relevant data. According to the JOA score, the patient's condition improved in 40.1% of cases (107/267), remained unchanged in 50.2% (134/267), and worsened in 9.7% (26/267). Notably, there was no association between clinical outcomes and syringomyelia regression (p = 0.227) or changes in the cerebellar tonsillar position (p = 0.323). CONCLUSIONS: FMDD is a simple, safe, and effective surgical procedure for adult CMI that yields significant and sustained improvement in clinical and radiological outcomes. However, clinical improvement does not always correlate with syringomyelia regression and cerebellar tonsillar shift.

Risk Genetic Variants (IL-10) for Osteoporosis in Han Population from Northwest China.

Background: Osteoporosis (OP) is a common metabolic bone disease characterized by loss of bone mass. IL-10 is considered to be a powerful immune and inflammatory suppressor. This study aimed to assess association between genetic loci in IL-10 and susceptibility to OP. Methods: Association analysis between IL-10 genetic loci and OP risk through SNPStats online software. FPRP analysis (false-positive report probability) verified whether the positive results were noteworthy findings. Linkage disequilibrium (LD) and haplotype analysis were completed by Haploview 4.2 and SNPStats. Multi-factor dimensionality reduction (MDR) was used to assess interaction of SNP-SNP in susceptibility to OP. Results: Allele "G" of IL-10-rs1554286 (OR = 1.21, p = 0.013), allele "C" of IL-10-rs1518111 (OR = 1.22, p = 0.011), allele "C" of IL-10-rs3024490 (OR = 1.20, p = 0.018), and allele "G" of IL-10-rs1800871 (OR = 1.21, p = 0.015) were risk factors for OP. In females, smoking, drinking, or aging ≤60 years old participants, the above genetic loci are also significantly associated with the increased risk of OP. FPRP analysis showed that all positive results are noteworthy findings. There are significant differences in serum levels of uric acid, mean hemoglobin concentration, or mean hemoglobin among different genotypes of IL-10 gene loci. MDR showed that four loci model composed rs1554286, rs1518111, rs3021094, and rs1800871 is the best model for predicting OP risk. Conclusion: IL-10-rs1554286, -rs1518111, -rs3021094, and -rs1800871 are risk factors for susceptibility to OP.

Genomic profiling and prognostic factors of H3 K27M-mutant spinal cord diffuse glioma.

H3 K27-altered diffuse midline glioma is a highly lethal pediatric-type tumor without efficacious treatments. Recent findings have highlighted the heterogeneity among diffuse midline gliomas with different locations and ages. Compared to tumors located in the brain stem and thalamus, the molecular and clinicopathological features of H3 K27-altered spinal cord glioma are still largely elusive, thus hindering the accurate management of patients. Here we aimed to characterize the clinicopathological and molecular features of H3 K27M-mutant spinal cord glioma in 77 consecutive cases. We found that the H3 K27M-mutant spinal cord glioma, with a median age of 35 years old, had a significantly better prognosis than H3 K27M-mutant brain tumors. We noticed a molecular heterogeneity of H3 K27M-mutant spinal cord astrocytoma via targeted sequencing with 34 cases. TP53 mutation which occurred in 58.8% of cases is mutually exclusive with PPM1D (26%) and NF1 (44%) mutations. The TP53-mutant cases had a significantly higher number of copy number variants (CNV) and a marginally higher proportion of pediatric patients (age at diagnosis <18 years old, p = 0.056). Cox regression and Kaplan-Meier curve analysis showed that the higher number of CNV events (≥3), chromosome (Chr) 9p deletion, Chr 10p deletion, ATRX mutation, CDK6 amplification, and retinoblastoma protein (RB) pathway alteration are associated with worse survival. Cox regression analysis with clinicopathological features showed that glioblastoma histological type and a high Ki-67 index (>10%) are associated with a worse prognosis. Interestingly, the histological type, an independent prognostic factor in multivariate Cox regression, can also stratify molecular features of H3 K27M-mutant spinal cord glioma, including the RB pathway, KRAS/PI3K pathway, and chromosome arms CNV. In conclusion, although all H3 K27M-mutant spinal cord diffuse glioma were diagnosed as WHO Grade 4, the histological type, molecular features representing chromatin instability, and molecular alterations associated with accelerated cell proliferative activity should not be ignored in clinical management.

Morinda officinalis polysaccharide attenuates osteoporosis in rats underwent bilateral ovariectomy by suppressing the PGC-1α/PPARγ pathway.

OBJECTIVE: Osteoporosis (OP) is a widespread disease that causes risks of spine and hip fractures. Morinda officinalis polysaccharide (MOP) shows therapeutic potential in OP. This article intended to understand the mechanism by which MOP impacts bone mineral density (BMD) and serum trace elements in OP rats. METHODS: OP rat models were established by bilateral ovariectomy (OVX). Rats were intragastrically administered with MOP or ZLN005 [the activator of peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α)] since the first day after operation for 8 weeks. Microstructural changes in OP rats were analyzed using micro-computed tomography system. Contents of serum Zn, Cu, Fe, and Mg in rats were measured. Levels of serum superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), GSH, and malondialdehyde (MDA) in rats were determined by Enzyme-linked immunosorbent assay. Protein levels of PGC-1α and peroxisome proliferator-activated receptor γ (PPARγ) in cartilage tissues of rats were determined via Western blotting. RESULTS: MOP enhanced BMD, bone volume per trabecular volume (BV/TV), Tb.N, and Tb.Th and reduced Tb.Sp in the distal femur of OVX rats, elevated levels of serum Cu, Fe, and Mg and contents of SOD, GSH, and GSH-PX and decreased MDA content. Moreover, MOP suppressed the PGC-1α/PPARγ pathway. Activation of PGC-1α partially abolished the action of MOP on ameliorating OP in OVX rats and strengthening anti-oxidation ability. CONCLUSION: MOP mitigated OP in OVX rats by inhibiting the PGC-1α/PPARγ pathway.

Exploring the Correlation between Changes in Gut Microbial Community Diversity and Depression in Human Populations.

Depression, also known as depressive disorder, is a group of psychosomatic affective disorders characterized by persistent and significantly depressed mood, delayed thinking, and cognitive impairment. The aim of this study was to explore the correlation between changes in gut microbial community diversity and depression to provide data on new strategies for the prevention and treatment of depression. In this study, we separated participants into a group of depressed patients and a healthy comparison group. We analyzed the gut microbial community structure of depressed patients and healthy comparisons using second-generation sequencing of the bacterial 16S RNA gene. There were significant differences in the gut microflora structure between patients with depression and healthy individuals. The gut flora alpha diversity index was significantly reduced in patients with depression compared to that in the healthy population. At the species level, the relative abundance of Coprococcus catus and Bacteroides barnesiae was significantly lower in the depressed group than that in the control group. The development of depression may be associated with a decrease in beneficial gut bacteria.

Interrogation of the microenvironmental landscape in spinal ependymomas reveals dual functions of tumor-associated macrophages.

Spinal ependymomas are the most common spinal cord tumors in adults, but their intratumoral cellular heterogeneity has been less studied, and how spinal microglia are involved in tumor progression is still unknown. Here, our single-cell RNA-sequencing analyses of three spinal ependymoma subtypes dissect the microenvironmental landscape of spinal ependymomas and reveal tumor-associated macrophage (TAM) subsets with distinct functional phenotypes. CCL2+ TAMs are related to the immune response and exhibit a high capacity for apoptosis, while CD44+ TAMs are associated with tumor angiogenesis. By combining these results with those of single-cell ATAC-sequencing data analysis, we reveal that TEAD1 and EGR3 play roles in regulating the functional diversity of TAMs. We further identify diverse characteristics of both malignant cells and TAMs that might underlie the different malignant degrees of each subtype. Finally, assessment of cell-cell interactions reveal that stromal cells act as extracellular factors that mediate TAM diversity. Overall, our results reveal dual functions of TAMs in tumor progression, providing valuable insights for TAM-targeting immunotherapy.

Spinal Cord Diffuse Midline Gliomas With H3 K27m-Mutant: Clinicopathological Features and Prognosis.

BACKGROUND: "Diffuse midline glioma, H3 K27M-mutant" (DMG) mainly arises within the pontine, thalamic, and spinal cord regions. Because of the rarity of spinal cord gliomas, the general knowledge surrounding DMGs is mainly based on pontine and thalamic gliomas, whereas tumor location tends to influence the clinicopathological features and prognosis. OBJECTIVE: To determine the clinicopathological characteristics and molecular profiles of DMGs located in the spinal cord. METHODS: The clinical and molecular pathologic features and prognosis were comprehensively analyzed in a series of 44 patients with spinal cord DMGs. RESULTS: The median age was 36 yr, and 88.7% of patients (39/44) were adults (≥18 yr). Histopathologically, malignant grades included grade II (16 cases), grade III (20 cases), and grade IV (8 cases). Compared with patients with histological grade IV, patients with lower histological grade (grade II/III) were older (37 vs 24 yr, P = .020) and were associated with longer overall survival (24.1 vs 8.6 mo, P = .007). All 30 tested tumors were isocitrate dehydrogenase (IDH) wild type, and 96% of cases (22/23) presented with unmethylated O6-methylguanine-DNA methyltransferase. Univariate and multivariate analyses showed that histological grade and presurgery McCormick Scale scores were independent prognostic factors for overall survival, whereas extensive surgical resection and chemoradiotherapy were not significantly associated with improved survival. The most frequent anatomic locations were the cervical enlargement (C4-T1, n = 16) and conus medullaris (T12-L1, n = 13), which exhibited distinctive clinical characteristics and molecular features. CONCLUSION: The findings provide guidelines for the evidence-based practice of the specialized management of spinal cord DMGs.

A comprehensive model including preoperative peripheral blood inflammatory markers for prediction of the prognosis of diffuse spinal cord astrocytoma following surgery.

PURPOSE: Due to the rarity of diffuse spinal cord astrocytoma, an effective model is still lacking to stratify their prognosis. Here, we aimed to establish a prognostic model through comprehensively evaluating clinicopathological features and preoperative peripheral blood inflammatory markers in 89 cases. METHODS: We performed univariate and multivariate Cox regression to identify prognosis factors. The Kaplan-Meier curves and ROC curves were employed to compare the prognostic value of selected factors. RESULTS: In addition to clinicopathological factors, we revealed the preoperative peripheral blood leukocyte count, neutrophils-to-lymphocytes ratio (NLR), and platelet-to-lymphocyte ratio (PLR) were also significantly correlated with overall survival of spinal cord astrocytoma in univariate Cox regression, and NLR was still significant in multivariate Cox analysis. Further, we demonstrated that NLR ≤ 3.65 and preoperative McCormick score (MMS) ≤ 3 were independently correlated with better survival of WHO grade IV tumors. Meanwhile, Ki-67 < 10% and resection extent ≥ 90% were independent prognostic factors in WHO grade II/III tumors. Finally, we developed a prognostic model that had better predictive efficiencies than WHO grade and histological grade for 1-year (AUC = 76.6), 2- year (AUC = 80.9), and 3-year (AUC = 80.3) survival. This model could classify tumors into 4 classifications with increasingly poor prognosis: 1, WHO grade II/III, with Ki-67 < 10% and resection extent ≥ 90%; 2, WHO grade II/III, Ki-67 ≥ 10% or resection < 90%; 3, WHO grade IV, NLR ≤ 3.65 and MMS ≤ 3; 4, WHO grade IV, with NRL > 3.65 or MMS = 4. CONCLUSION: We successfully constructed a comprehensive prognostic model including preoperative peripheral blood inflammatory markers, which can stratify diffuse spinal cord astrocytoma into 4 subgroups.

Clinicopathological characteristics and survival of spinal cord astrocytomas.

BACKGROUND: Due to their rarity, the clinicopathological characteristics and prognostic factors of spinal cord gliomas are still unclear. Here, we aimed to clarify these issues in a cohort of 108 spinal cord astrocytomas. METHODS: We characterized the clinicopathological characteristics, including 2016 World Health Organization (WHO) grade, age, sex, location, segment length, resection, pre- and postsurgery, Modified McCormick Scale (MMS), radio- and chemotherapy, and Ki-67 and H3 K27M mutations, in 108 spinal cord astrocytomas through heatmaps. The Cox regression analysis and Kaplan-Meier curves were used to study the prognostic value of these clinicopathological features. RESULTS: There are a total 38 H3 K27M-mutant tumors, including 31 cases with histological grade II/III tumors. The age of low-grade astrocytoma patients (WHO grade I/II, n = 54) was significantly younger (27.0 vs 35.5 years, P = .001) than those with high-grade tumors (WHO grade III/IV, n = 54). All patients underwent surgical resection with neurophysiological monitoring, and the surgery did not result in significant changes in MMS. The presurgery MMS was associated with overall survival in the high-grade subgroup (P = .008) but not in the low-grade subgroup (P = .312). While, the high content of resection improved the survival of only patients with low-grade astrocytomas (P = .016) but not those with high-grade astrocytomas (P = .475). Both the low-grade and high-grade astrocytomas had no obvious benefit from neither adjuvant chemotherapy nor radiotherapy (all P > .05). CONCLUSIONS: We characterized the clinicopathological characteristics and their prognostic values in 108 spinal cord astrocytomas, which could help with evidence-based management of spinal cord astrocytomas.

The molecular characteristics of spinal cord gliomas with or without H3 K27M mutation.

Due to the rare incidence of spinal cord astrocytomas, their molecular features remain unclear. Here, we characterized the landscapes of mutations in H3 K27M, isocitrate dehydrogenase 1 (IDH1) R132H, BRAF V600E, and the TERT promoter in 83 diffuse spinal cord astrocytic tumors. Among these samples, thirty-five patients had the H3 K27M mutation; this mutant could be observed in histological grade II (40%), III (40%), and IV (20%) astrocytomas. IDH1 mutations were absent in 58 of 58 cases tested. The BRAF V600E mutation (7/57) was only observed in H3-wildtype astrocytomas, and was associated with a better prognosis in all histological grade II/III astrocytomas. TERT promoter mutations were observed in both H3 K27M-mutant (4/25) and -wildtype (9/33) astrocytomas, and were associated with a poor prognosis in H3-wildtype histological grade II/III astrocytomas. In the 2016 WHO classification of CNS tumors, H3 K27M-mutant diffuse midline gliomas, including spinal cord astrocytomas, are categorized as WHO grade IV. Here, we noticed that the median overall survival of histological grade II/III H3 K27M-mutant cases (n = 28) was significantly longer than that of either the total histological grade IV cases (n = 12) or the H3 K27M-mutant histological grade IV cases (n = 7). We also directly compared H3 K27M-mutant astrocytomas to H3-wildtype astrocytomas of the same histological grade. In histological grade II astrocytomas, compared to H3-wildtype cases (n = 37), H3 K27M-mutant patients (n = 14) had showed a significantly higher Ki-67-positive rate and poorer survival rate. However, no significant differences in these parameters were observed in histological grade III and IV astrocytoma patients. In conclusion, these findings indicate that spinal cord astrocytomas are considerably different from hemispheric and brainstem astrocytomas in terms of their molecular profiles, and that the histological grade cannot be ignored when assessing the prognosis of H3 K27M-mutant spinal cord astrocytomas.

Effect of thermomechanical treatment on the mechanical and microstructural evolution of a ß-type Ti-40.7Zr-24.8Nb alloy.

In this study, the microstructural evolution and mechanical properties of a newly developed Ti-40.7Zr-24.8Nb (TZN) alloy after different thermomechanical processes were examined. As-cast TZN alloy plates were solution-treated at 890 °C for 1 h, after which the thickness of the alloy plates was reduced by cold rolling at reduction ratios of 20%, 56%, 76%, and 86%. Stress-induced α" formation, {332} <113> ß mechanical twinning, and kink band formation were observed in the cold-rolled TZN alloy samples. In the TZN sample after cold rolling at the 86% reduction ratio plus a recrystallization annealing at 890 °C for 1 h, the deformation products of a stress-induced α" phase, {332}<113> ß mechanical twinning, and kink bands disappeared, resulting in a fine, equiaxed single ß phase. The alloy samples exhibited elongation at rupture ranging from 7% to 20%, Young's modulus ranging from 63 to 72 GPa and tensile strength ranging from 753 to 1158 MPa. The TZN alloy sample after cold rolling and recrystallization annealing showed a yield strength of 803 MPa, a tensile strength of 848 MPa, an elongation at rupture of 20%, and an elastic admissible strain of 1.22%, along with the most ductile fractures during tensile testing.

[Determination of 2,4-diaminotoluene in Mianpi composite packaging film bags by ion-exchange solid-phase extraction-gas chromatography-mass spectrometry].

A method for the determination of 2,4-diaminotoluene in Mianpi composite packaging film bags was established based on ion-exchange solid-phase extraction-gas chromatography-mass spectrometry (GC-MS). The samples were immersed in 4% (v/v) acetic acid solution. 2,4-Diaminotoluene was enriched from a 50.0 mL soak solution with an activated and balanced MCX solid-phase extraction column. The MCX column was washed with 5.0 mL water and eluted with 3.0 mL ammoniated methanol. 2,4-Diaminotoluene was detected quantitatively by GC-MS after derivatization with heptafluorobutyric acid anhydride. In the mass concentration range of 1-50 µg/L, the linear correlation coefficient (r) was 0.9991. The limit of detection (LOD, S/N=3) was 0.2 µg/L, and the limit of quantification (LOQ, S/N=10) was 0.6 µg/L. The recovery of 2,4-diaminotoluene was in the range of 89.0%-94.2%. The relative standard deviations (RSDs) were 1.9%-3.6%. This method requires neither pH adjustment of the soak solution in the pre-processing step nor liquid-liquid extraction. With this method, the pre-processing step is greatly simplified and there is minimal consumption of organic solvents. Further, the method is simple, convenient, and accurate, and it is suitable for the determination of 2,4-diaminotoluene in Mianpi composite packaging film bags.

Deformation mechanism and mechanical properties of a thermomechanically processed ß Ti-28Nb-35.4Zr alloy.

The effects of thermomechanical treatment on the microstructure and mechanical properties of a newly developed ß titanium alloy, i.e., Ti-28Nb-35.4Zr (wt%, hereafter denoted Ti-Nb-Zr) were investigated. The as-cast Ti-Nb-Zr alloy was subjected to solution treatment at 890°C for 1h, after which its thickness was reduced by 20%, 56%, 76%, and 86% via cold rolling. Results indicated that annealing at 890°C for 1h after cold rolling at a thickness reduction ratio of 86% resulted in a phase transformation from the stress-induced α" and ω into ß, leading to a recrystallization of a uniform single ß phase. The recrystallized Ti-Nb-Zr alloy exhibited a tensile strength of 633MPa, Young's modulus of 63GPa, and elongation at rupture of 13%, respectively. The cold rolled specimens showed a higher Young's modulus than that of the recrystallized specimen due to the stress-induced ω phase. Transmission electron microscopy (TEM) analysis revealed that ω, α" and ß phases co-existed in the microstructure of the cold-rolled specimens. Electron backscatter diffraction analysis revealed that the deformation mechanisms during thermomechanical processing included kink bands, {332}<113> twins and shear bands; and the predominant deformation mechanism depended on the extent of CR deformation.

JNK pathway mediates curcumin-induced apoptosis and autophagy in osteosarcoma MG63 cells.

Human osteosarcoma is a common primary malignancy of the bone in children and adolescents. It has been reported that curcumin is able to induce apoptosis in osteosarcoma MG63 cells through the mitochondrial pathway. However, whether curcumin is able to induce autophagy and the interaction between apoptosis and autophagy in osteosarcoma cells has yet to be fully elucidated. In the current study, it was determined that curcumin was able to significantly induce apoptosis, and lead to autophagy in MG63 cells. Notably, inhibition of apoptosis enhanced curcumin-induced autophagy due to upregulation of the c-Jun N-terminal kinase (JNK) signaling pathway. This finding was confirmed by the use of JNK-specific inhibitor, SP600125. Furthermore, our data showed that curcumin-induced apoptosis was increased when autophagy was completely inhibited by 3-methyladenine in MG63 cells. These results suggest that autophagy may have an important role in resistance to apoptosis when MG63 cells are incubated with curcumin. Thus, these results provide important insights into the interaction between apoptosis and autophagy in osteosarcoma cells and clinical treatment strategies using curcumin.