Clinicopathological analysis of non-functioning pituitary adenomas (PAs) according to the 2022 WHO classification.

PURPOSE: For asymptomatic non-functioning pituitary adenomas (NFPAs), conservative approaches such as observation are preferred. However, some NFPAs exhibit poor prognoses. Thus, the purpose of this study was to investigate clinicopathological characteristics of tumors for identifying those with unfavorable prognoses. METHODS: A total of 125 patients with NFPAs who underwent surgery between November 2017 and December 2022 at our institution were retrospectively analyzed. Clinical, radiological, and pathological data, including hormone profiles, tumor size, presence of cavernous sinus invasion, and Ki-67 index levels, were reviewed. High-risk PAs were identified according to 2022 WHO criteria. Statistical analyses including Kaplan-Meier survival analysis and Cox regression were performed to evaluate factors associated with tumor progression or recurrence. RESULTS: A high-risk group demonstrated a significantly higher rate of tumor progression/recurrence than a low-risk group (p-value = 0.004). In multivariate analysis, the high-risk group at the time of diagnosis remained as an independent prognostic factor for NFPAs (p-value = 0.0148). The high-risk group also had a higher percentage of younger patients (80.0% in the high-risk group vs. 62.2% in the low-risk group, p-value = 0.016) and female patients (91.4% vs. 34.4%, p< 0.001). The presence of cavernous sinus invasion and higher Ki-67 index levels were more commonly observed in the high-risk group, although these factors did not significantly impact the overall prognosis. CONCLUSION: Our findings indicate that patients with high-risk NFPAs have a more aggressive disease course and a higher rate of progression or recurrence. This high-risk group has higher prevalence of younger and female patients. They may benefit from closer monitoring and possibly more aggressive treatment approaches.

Zeolite Membrane-Based Low-Temperature Dehydrogenation of a Liquid Organic Hydrogen Carrier: A Key Step in the Development of a Hydrogen Economy.

Methylcyclohexane (MCH) dehydrogenation is an equilibrium-limited reaction that requires high temperatures (>300 °C) for complete conversion. However, high-temperature operation can degrade catalytic activity and produce unwanted side products. Thus, a hybrid zeolite membrane (Z) is prepared on the inner surface of a tubular support and used it as a wall in a membrane reactor (MR) configuration. Pt/C catalysts is packed diluted with quartz sand inside the Z-coated tube and applied the MR for MCH dehydrogenation at low temperatures (190-250 °C). Z showed a remarkable H2-permselectivity in the presence of both toluene and MCH, yielding separation factors over 350. The Z-based MR achieved higher MCH conversion (75.3% ± 0.8% at 220 °C) than the conventional packed-bed reactor (56.4% ± 0.3%) and the equilibrium state (53.2%), owing to the selective removal of H2 through Z. In summary, the hybrid zeolite MR enhances MCH dehydrogenation at low temperatures by overcoming thermodynamic limitations and improves the catalytic performance and product selectivity of the reaction.

Delineation of three-dimensional tumor margins based on normalized absolute difference mapping via volumetric optical coherence tomography.

The extent of surgical resection is an important prognostic factor in the treatment of patients with glioblastoma. Optical coherence tomography (OCT) imaging is one of the adjunctive methods available to achieve the maximal surgical resection. In this study, the tumor margins were visualized with the OCT image obtained from a murine glioma model. A commercialized human glioblastoma cell line (U-87) was employed to develop the orthotopic murine glioma model. A swept-source OCT (SS-OCT) system of 1300 nm was used for three-dimensional imaging. Based on the OCT intensity signal, which was obtained via accumulation of each A-scan data, an en-face optical attenuation coefficient (OAC) map was drawn. Due to the limited working distance of the focused beam, OAC values decrease with depth, and using the OAC difference in the superficial area was chosen to outline the tumor boundary, presenting a challenge in analyzing the tumor margin along the depth direction. To overcome this and enable three-dimensional tumor margin detection, we converted the en-face OAC map into an en-face difference map with x- and y-directions and computed the normalized absolute difference (NAD) at each depth to construct a volumetric NAD map, which was compared with the corresponding H&E-stained image. The proposed method successfully revealed the tumor margin along the peripheral boundaries as well as the margin depth. We believe this method can serve as a useful adjunct in glioma surgery, with further studies necessary for real-world practical applications.

Cell-engineered virus-mimetic nanovesicles for vaccination against enveloped viruses.

Enveloped viruses pose a significant threat to human health, as evidenced by the recent COVID-19 pandemic. Although current vaccine strategies have proven effective in preventing viral infections, the development of innovative vaccine technologies is crucial to fortify our defences against future pandemics. In this study, we introduce a novel platform called cell-engineered virus-mimetic nanovesicles (VNVs) and demonstrate their potential as a vaccine for targeting enveloped viruses. VNVs are generated by extruding plasma membrane-derived blebs through nanoscale membrane filters. These VNVs closely resemble enveloped viruses and extracellular vesicles (EVs) in size and morphology, being densely packed with plasma membrane contents and devoid of materials from other membranous organelles. Due to these properties, VNVs express viral membrane antigens more extensively and homogeneously than EVs expressing the same antigen. In this study, we produced severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) VNVs expressing the SARS-CoV-2 Spike glycoprotein (S) on their surfaces and assessed their preclinical efficacy as a COVID-19 vaccine in experimental animals. The administration of VNVs successfully stimulated the production of S-specific antibodies both systemically and locally, and immune cells isolated from vaccinated mice displayed cytokine responses to S stimulation.

Repeated Injections of Mesenchymal Stem Cell-Derived Exosomes Ameliorate Erectile Dysfunction in a Cavernous Nerve Injury Rat Model.

PURPOSE: To evaluate the therapeutic effect of repeated injections of mesenchymal stem cell (MSC)-derived exosomes on the erectile dysfunction (ED) of bilateral cavernous nerve injury (BCNI) rat model and to identify potential target genes of these injections. MATERIALS AND METHODS: MSC-derived exosomes were isolated using an aqueous two-phase system. Rats were randomly assigned into four groups: Normal, BCNI, exosome once, and exosome-repeat groups. After four weeks, we measured the intracavernosal pressure (ICP)/mean arterial pressure (MAP) ratio to evaluate erectile function and examined cavernous nerve tissues for histological and molecular analyses. RNA sequencing in penile tissues was used to determine differentially expressed genes and was verified by quantitative polymerase chain reaction. Human umbilical vein endothelial cells (HUVECs) were used for in vitro studies to analyze biological roles. RESULTS: The ICP/MAP ratios in the exosome-once and exosome-repeat groups were significantly increased compared to those in the BCNI group. Interestingly, the ICP/MAP ratio showed a greater increase in the exosome-repeat group, which also showed significantly increased smooth muscle/collagen ratio, α-smooth muscle actin and neuronal nitric oxide synthase expression, and cyclic guanosine monophosphate level compared to the BCNI and exosome-once groups. Three genes were significantly differentially expressed in the exosome group, among which Ras homolog family member B promoted cell proliferation and angiogenesis of HUVECs. CONCLUSIONS: Repeated injections of MSC-derived exosomes can be effective in the treatment of rat models with ED induced by cavernous nerve injury.

Sinonasal Outcomes of the Combined Transseptal/Transnasal Approach with Unilateral Nasoseptal Rescue Flap in Endoscopic Endonasal Transsphenoidal Surgery: A Propensity Score Matching Analysis.

Objectives The authors applied surgical techniques acquired during the use of endoscopic combined transseptal/transnasal approach to reduce approach-related morbidity and improve sinonasal outcomes. Study Design This is a retrospective cohort study of a prospectively collected database. Setting The study setting involves a tertiary referral center. Participants A total of 86 patients who underwent endoscopic endonasal transsphenoidal surgery for newly diagnosed pituitary adenomas from April 2018 to March 2021 were included. Patients treated via the combined transseptal/transnasal approach served as the study group ( n = 18); those treated via the bilateral transnasal approach comprised the control group ( n = 68). From the control group, propensity score matching (PSM) analysis was further performed to account for potential confounders and selection bias. Main Outcome Measures Paired analysis was performed for pre- and 6-month-postoperative time points in study group, control group, and PSM control group. Olfactory function was evaluated by Connecticut Chemosensory Clinical Research Center (CCCRC) test, Cross-Cultural Smell Identification Test (CCSIT), and sinonasal outcomes were assessed by Sino-Nasal Outcome Test-22 (SNOT-22). Results In the study group, CCCRC ( p = 0.517) and CCSIT ( p = 0.497) did not show any significant difference before and after surgery. There was some improvement in the symptom score of SNOT-22, but it was not statistically significant ( p = 0.115). In the control group adjusted with PSM, a significant decrease in olfaction ( p = 0.047) was observed using CCCRC. The CCSIT score was also decreased but not significant ( p = 0.163). Also, there was no difference in the improvement of SNOT-22 ( p = 0.781). Conclusion Our new surgical method preserves olfactory function without compromising surgical outcomes.

Numerical investigation of acoustic cavitation and viscoelastic tissue deformation.

Acoustic cavitation and tissue deformation are studied by modifying a level-set method for compressible two-phase flows to consider viscoelastic tissue deformation. The numerical simulations performed using different shear moduli and bubble-tissue distances demonstrate various interactions between bubble and viscoelastic tissue, including inverted cone-shape bubbles, bubble migration, liquid jet formation, compressive and expansive tissue deformation, and tissue perforation. The bubble is observed to grow larger with increasing tissue bulk modulus and density. The maximum tissue deformation generally increases with decreasing initial bubble-tissue distance and with increasing tissue bulk modulus and density. The tissue shear modulus conditions that maximize tissue deformation are in the range of 1-10 MPa, unless the tissue density is very large.

Establishment of tumor microenvironment-preserving organoid model from patients with intracranial meningioma.

BACKGROUND: Although meningioma is the most common primary brain tumor, treatments rely on surgery and radiotherapy, and recurrent meningiomas have no standard therapeutic options due to a lack of clinically relevant research models. Current meningioma cell lines or organoids cannot reflect biological features of patient tumors since they undergo transformation along culture and consist of only tumor cells without microenvironment. We aim to establish patient-derived meningioma organoids (MNOs) preserving diverse cell types representative of the tumor microenvironment. METHODS: The biological features of MNOs were evaluated using WST, LDH, and collagen-based 3D invasion assays. Cellular identities in MNOs were confirmed by immunohistochemistry (IHC). Genetic alteration profiles of MNOs and their corresponding parental tumors were obtained by whole-exome sequencing. RESULTS: MNOs were established from four patients with meningioma (two grade 1 and two grade 2) at a 100% succession rate. Exclusion of enzymatic dissociation-reaggregation steps endowed MNOs with original histology and tumor microenvironment. In addition, we used a liquid media culture system instead of embedding samples into Matrigel, resulting in an easy-to-handle, cost-efficient, and time-saving system. MNOs maintained their functionality and morphology after long-term culture (> 9 wk) and repeated cryopreserving-recovery cycles. The similarities between MNOs and their corresponding parental tumors were confirmed by both IHC and whole-exome sequencing. As a representative application, we utilized MNOs in drug screening, and mifepristone, an antagonist of progesterone receptor, showed prominent antitumor efficacy with respect to viability, invasiveness, and protein expression. CONCLUSION: Taken together, our MNO model overcame limitations of previous meningioma models and showed superior resemblance to parental tumors. Thus, our model could facilitate translational research identifying and selecting drugs for meningioma in the era of precision medicine.

Efficacy of Mesenchymal-Stromal-Cell-Derived Extracellular Vesicles in Ameliorating Cisplatin Nephrotoxicity, as Modeled Using Three-Dimensional, Gravity-Driven, Two-Layer Tubule-on-a-Chip (3D-MOTIVE Chip).

Mesenchymal stromal cell (MSC)-derived extracellular vesicles (EVs) are known to have a therapeutic effect on nephrotoxicity. As animal models require significant time and resources to evaluate drug effects, there is a need for a new experimental technique that can accurately predict drug effects in humans. We evaluated the therapeutic effect of MSC-derived EVs in cisplatin nephrotoxicity using a three-dimensional, gravity-driven, two-layer tubule-on-a-chip (3D-MOTIVE chip). In the 3D-MOTIVE chip, 10 µM cisplatin decreased the number of attached cells compared to the vehicle. Conversely, annexin V and reactive oxygen species (ROS) were increased. Cell viability was increased 2.8-fold and 2.5-fold after treatment with EVs at 4 and 8 µg/mL, respectively, compared to the cisplatin-induced nephrotoxicity group. Cell attachment was increased 2.25-fold by treatment with 4 µg/mL EVs and 2.02-fold by 8 µg/mL EVs. Annexin V and ROS levels were decreased compared to those in the cisplatin-induced nephrotoxicity group. There were no significant differences in annexin V and ROS levels according to EV concentration. In sum, we created a cisplatin-induced nephrotoxicity model on a 3D-MOTIVE chip and found that MSC-derived EVs could restore cell viability. Thus, MSC-derived EVs may have the potential to ameliorate cisplatin-induced nephrotoxicity.

Is reduced-dose whole-brain radiotherapy also feasible in primary CNS lymphoma for curative or salvage purpose?

PURPOSE: Recently, reduced-dose whole-brain radiotherapy (WBRT) has been used to treat primary central nervous system lymphoma (PCNSL). However, whether reduced-dose WBRT is also an acceptable option for curative or salvage purposes has not yet been reported. We analyzed the clinical outcomes of patients with PCNSL who received radiotherapy for curative or salvage purposes and compared the clinical outcomes according to the WBRT dose. METHODS: A total of 66 patients were divided into two groups: those treated with 30 Gy (2 Gy per fraction) or less WBRT (low-dose WBRT, n = 34) and those treated with more than 30 Gy WBRT (high-dose WBRT, n = 32). The median WBRT dose was 25.2 and 49.6 Gy in low-dose and high-dose WBRT groups, respectively. The median total radiotherapy dose, including the boost dose, was 50 Gy (range, 36.0-55.8 Gy). RESULTS: The 3-year overall survival and progression-free survival were 77.8% and 29.8%, respectively. Intracranial relapse occurred in 31 patients (47.0%) at a median of 27 months after RT. Overall survival and progression-free survival did not differ between the two groups. The 3-year intracranial disease control rate did not differ between the two groups (35.2% vs. 41.6%, p = 0.300). Grade 3 or higher neurological toxicities were observed in six patients, of whom five were in the high-dose WBRT group. CONCLUSION: Reduced-dose WBRT in curative and salvage treatments for PCNSL had no significant negative effect on the intracranial disease control rate or survival. Therefore, without impaired efficacy, use of reduced-dose WBRT appears promising for reduction of neurotoxicity.

Potential impact of high-density lipoprotein cholesterol in the postoperative outcomes of chronic subdural hematoma patients: multi-institutional study in Korea.

BACKGROUND: Chronic subdural hematoma (CSDH) is a common clinical situation in neurosurgical practice, but the optimal treatment option is controversial. This study aimed to evaluate the effect of cholesterol-lowering medications on and how they affected the prognoses of CSDH patients. METHODS: In this multi-institutional observational study performed in Korea, data from recently treated CSDH patients were gathered from 5 hospitals. A total of 462 patients were collected from March 2010 to June 2021. Patient clinical characteristics, history of underlying diseases and their treatments, radiologic features, and surgical outcomes were analyzed. RESULTS: Seventy-five patients experienced recurrences, and 62 had reoperations after the initial burr hole surgery. Among these, 15 patients with recurrences and 12 with reoperations were taking cholesterol-lowering medications. However, the use of medications did not significantly affect recurrence or reoperation rates (P = 0.350, P = 0.336, respectively). When analyzed by type of medication, no clinically relevant differences in total cholesterol (TC), triglyceride (TG), or low-density lipoprotein cholesterol (LDL-C) levels were identified. The combination of a statin drug and ezetimibe significantly elevated high-density lipoprotein cholesterol (HDL-C) levels (P = 0.004). TC, LDL-C, and TG levels did not significantly affect patient prognoses. However, HDL-C levels and recurrence (odds ratio (OR) = 0.96; 95% confidence interval (CI): 0.94-0.99; p = 0.010) were negatively correlated. An HDL-C level of 42.50 mg/dL was identified as the threshold for recurrence and reoperation. CONCLUSIONS: In this study, using cholesterol-lowering medications did not significantly impact the prognosis of patients who underwent surgical management for a chronic subdural hematoma. However, the findings showed that the higher the HDL-C level, the lower the probability of recurrence and reoperation.

Genomic surveillance of genes encoding the SARS-CoV-2 spike protein to monitor for emerging variants on Jeju Island, Republic of Korea.

Introduction: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has been fueled by new variants emerging from circulating strains. Here, we report results from a genomic surveillance study of SARS-CoV-2 on Jeju Island, Republic of Korea, from February 2021 to September 2022. Methods: A total of 3,585 SARS-CoV-2 positive samples were analyzed by Sanger sequencing of the gene encoding the spike protein before performing phylogenetic analyses. Results: We found that the Alpha variant (B.1.1.7) was dominant in May 2021 before being replaced by the Delta variant (B.1.617.2) in July 2021, which was dominant until December 2021 before being replaced by the Omicron variant. Mutations in the spike protein, including N440K and G446S, have been proposed to contribute to immune evasion, accelerating the spread of Omicron variants. Discussion: Our results from Juju Island, Republic of Korea, are consistent with and contribute to global surveillance efforts crucial for identifying new variants of concern of SARS-CoV-2 and for monitoring the transmission dynamics and characteristics of known strains.

Balancing Bleeding Risk and Thromboembolic Complications in Elderly Chronic Subdural Hematoma Patients Undergoing Burr Hole Trephination : A Multicenter Retrospective Cohort Study and Literature Review.

OBJECTIVE: Chronic subdural hematoma (CSDH) patients using antithrombotic agents (AT) at high risk for cardiovascular disease are increasing. The authors aimed to analyze the factors influencing outcome by targeting patients using AT and to establish a desirable treatment strategy. METHODS: A retrospective analysis was performed on data from 462 patients who underwent burr hole trephination (BHT) surgery for CSDH at five hospitals from March 2010 to June 2021. Outcomes included incidence of postoperative acute bleeding, recurrence rate, and morbidity or mortality rate. Patients were divided into the following four groups based on their history of AT use : no AT. Only antiplatelet agents (AP), only anticoagulants (AC), both of AP and AC. In addition, a concurrent literature review was conducted alongside our cohort study. RESULTS: Of 462 patients, 119 (119/462, 25.76%) were using AT. AP prescription did not significantly delay surgery (p=0.318), but AC prescription led to a significant increase in the time interval from admission to operation (p=0.048). After BHT, AP or AC intake significantly increased the period required for an in-dwelling drain (p=0.026 and p=0.037). The use of AC was significantly related to acute bleeding (p=0.044), while the use of AP was not (p=0.808). Use of AP or AC had no significant effect on CSDH recurrence (p=0.517 and p=1.000) or reoperation (p=0.924 and p=1.000). Morbidity was not statistically correlated with use of either AP or AC (p=0.795 and p=0.557, respectively), and there was no significant correlation with mortality for use of these medications (p=0.470 and p=1.000). CONCLUSION: Elderly CSDH patients may benefit from maintenance of AT therapy during BHT due to reduced thromboembolic risk. However, the use of AC necessitates individualized due to potential postoperative bleeding. Careful post-operative monitoring could mitigate prognosis and recurrence impacts.

Polymorphisms of Killer Ig-like Receptors and the Risk of Glioblastoma.

PURPOSE: The immune responses of natural killer (NK) cells against cancer cells vary by patient. Killer Ig-like receptors (KIRs), which are some of the major receptors involved in regulating NK cell activity for killing cancer cells, have significant genetic variation. Numerous studies have suggested a potential association between the genetic variation of KIR genes and the risk of development or prognosis of various cancer types. However, an association between genetic variations of KIR genes and glioblastoma (GB) remains uncertain. We sought to evaluate the association of genetic variations of KIRs and their ligand genes with the risk of GB development in Koreans. METHODS: A case-control study was performed to identify the odds ratios (ORs) of KIR genes and Classes A, B, and, C of the human leukocyte antigen (HLA) for GB. The GB group was comprised of 77 patients with newly diagnosed IDH-wildtype GB at our institution, and the control group consisted of 200 healthy Korean volunteers. RESULTS: There was no significant difference in the frequency of KIR genes and KIR haplotypes between the GB and control groups. Genetic variations of KIR-2DL1, 3DL1, and 3DS1 with their ligand genes (HLA-C2, HLA-Bw4/6, and Bw4, respectively) had effects on the risk of GB in Korean patients. The frequency of KIR-2DL1 with HLA-C2 (OR 2.05, CI 1.19-3.52, p = 0.009), the frequency of KIR-3DL1 without HLA-Bw4 (80I) (OR 8.36, CI 4.06-17.18, p < 0.001), and the frequency of KIR-3DL1 with Bw6 (OR 4.54, CI 2.55-8.09, p < 0.001) in the GB group were higher than in the control group. In addition, the frequency of KIR-2DL1 without HLA-C2 (OR 0.44, CI 0.26-0.75, p = 0.003), the frequency of KIR-3DL1 with HLA-Bw4 (80T) (OR 0.13, CI 0.06-0.27, p < 0.001), the frequency of KIR-3DL1 without Bw6 (OR 0.27, CI 0.15-0.49, p < 0.001), and the frequency of KIR-3DS1 with Bw4 (80I) (OR 0.03, CI 0.00-0.50, p < 0.001) in the GB group were lower than in the control group. CONCLUSIONS: This study suggests that genetic variations of KIRs and their ligand genes may affect GB development in the Korean population. Further investigations are needed to demonstrate the different immune responses for GB cells according to genetic variations of KIR genes and their ligand genes.

Single-center study on clinicopathological and typical molecular pathologic features of metastatic brain tumor.

BACKGROUND: The metastatic brain tumor is the most common brain tumor. The aim of this study was to demonstrate the clinicopathological and molecular pathologic features of brain metastases (BM). METHODS: A total of 269 patients were diagnosed with BM through surgical resection at Seoul St. Mary's Hospital from January 2010 to March 2020. We reviewed the clinicopathological features and molecular status of primary and metastatic brain tissues using immunohistochemistry and molecular pathology results. RESULTS: Among 269 patients, 139 males and 130 females were included. The median age of primary tumor was 58 years (range, 13 to 87 years) and 86 patients (32.0%) had BM at initial presentation. Median BM free interval was 28.0 months (range, 1 to 286 months). The most frequent primary site was lung 46.5% (125/269), and followed by breast 15.6% (42/269), colorectum 10.0% (27/269). Epidermal growth factor receptor (EGFR) mutation was found in 50.8% (32/63) and 58.0% (40/69) of lung primary and BM, respectively. In both breast primary and breast cancer with BM, luminal B was the most frequent subtype at 37.9% (11/29) and 42.9% (18/42), respectively, followed by human epidermal growth factor receptor 2 with 31.0% (9/29) and 33.3% (14/42). Triple-negative was 20.7% (6/29) and 16.7% (7/42), and luminal A was 10.3% (3/29) and 7.1% (3/42) of breast primary and BM, respectively. In colorectal primary and colorectal cancer with BM, KRAS mutation was found in 76.9% (10/13) and 66.7% (2/3), respectively. CONCLUSIONS: We report the clinicopathological and molecular pathologic features of BM that can provide useful information for understanding the pathogenesis of metastasis and for clinical trials based on the tumor's molecular pathology.

Glioma grading using multiparametric MRI: head-to-head comparison among dynamic susceptibility contrast, dynamic contrast-enhancement, diffusion-weighted images, and MR spectroscopy.

PURPOSE: To assess the diagnostic accuracy of dynamic susceptibility contrast, dynamic contrast-enhancement, MR spectroscopy (MRS), and diffusion-weighted imaging for differentiating high-grade (HGGs) from low-grade gliomas (LGGs). METHODS: Seventy-two patients (16 LGGs, 56 HGGs) with pathologically confirmed gliomas were retrospectively included. From three-dimensionally segmented tumor, histogram analyses of relative cerebral blood volume (rCBV), volume transfer constant (Ktrans), and apparent diffusion coefficient (ADC) were performed. Choline-to-creatinine ratio (Cho/Cr) was calculated using MRS. Logistic regression analyses were performed to differentiate HGGs (grade ≥ 3) from LGGs (grade ≤ 2). Areas under the receiver operating characteristics curves (AUC) were plotted. Subgroup analysis was performed between IDH-wildtype glioblastomas and IDH-mutant astrocytomas. Pairwise Spearman's correlation coefficients (ρ) were computed. RESULTS: HGGs had higher 95th percentile rCBV, Ktrans and Cho/Cr (P < 0.01) than LGGs. AUC of 95th percentiles of rCBV and Ktrans were 0.79 (95% CI, 0.67-0.91) and 0.74 (95% CI, 0.59-0.88), respectively. AUC of 5th percentile of ADC was 0.63 (95% CI, 0.48-0.79), and that of Cho/Cr was 0.67 (95% CI, 0.52-0.81). IDH-wildtype glioblastomas and IDH-mutant astrocytomas showed significantly different 95th percentile rCBV (P = 0.04) and Ktrans (P < 0.01), with Ktrans showing the highest AUC (0.73, 95% CI 0.57-0.89) in IDH status prediction. Moderate correlations were observed between 95th percentile rCBV and Ktrans (ρ = 0.47), Cho/Cr (ρ = 0.40), and 5th percentile ADC (ρ = -0.36) (all P < 0.01). CONCLUSIONS: The 95th percentile rCBV may be most helpful in discriminating HGGs from LGGs. The 95th percentile Ktrans may aid predicting IDH status of diffuse gliomas.

A clinical evaluation of cystic features in patients with newly diagnosed glioblastoma with IDH-wildtype.

BACKGROUND: The prognostic significance of the presence of cystic features in patients with newly diagnosed glioblastoma (GB) is highly controversial. The purpose of this study was to determine whether cystic GB patients have a more favorable prognosis compared to non-cystic GB patients. METHODS: The records of all GB patients diagnosed between August 2008 and December 2020 at Seoul St. Mary's Hospital were reviewed retrospectively. Out of 254 GB patients, we excluded patients with a confirmed isocitrate dehydrogenase (IDH) mutation or an unknown IDH mutation status. A total of 145 patients met our eligibility criteria. RESULTS: Of the 145 patients we analyzed, 16 patients were classified as the cystic group, and 129 patients were classified into the non-cystic group. As there was a significant difference in the extent of resection between the two groups, 32 patients were matched according to propensity score matching. A Kaplan-Meier survival curve of the two groups indicated that the cystic group had better survival than the non-cystic group (28.6 months versus 18.8 months, respectively; p = 0.055). On multivariate analysis, the presence of cystic features (hazard ratio [HR]: 0.40, 95% confidence interval [CI]: 0.17-0.91, p = 0.029) was significantly related with a longer OS. Longer OS was also related with well-known prognostic factors, such as grossly total resection (HR: 0.05, CI: 0.01-0.31, respectively; p = 0.001) and lower European Cooperative Oncology Group (ECOG) score (HR: 3.67, CI: 1.56-9.02, respectively; p = 0.003). CONCLUSION: Our results suggest that the presence of cystic features could be an independent prognostic factor suggesting better survival in GB patients. Further larger and prospective studies to validate our findings are needed.

Differences in the predicted nasoseptal flap length among races: A propensity score matching analysis.

OBJECTIVES: We compared the lengths of a nasoseptal flap (NSF) and skull base according to race, age, and sex. METHODS: We performed paranasal sinus computed tomography in 19,961 adult patients between 2003 and 2022. The race of the patients was East Asian (n = 71), Caucasian (n = 71), or Middle Eastern (n = 71). The expected lengths of the NSF and anterior skull base defect were measured and analyzed according to race, age, and sex. RESULTS: Compared with Caucasians and Middle Easterners, East Asians had a shorter NSF length (p < 0.001) and lower ratio of the expected NSF length to the expected defect length (p < 0.001). There was no difference in the values among age groups. The expected NSF length was longer, and the ratio of the expected NSF length to the expected defect length was higher, in males than females (p < 0.001 for both). CONCLUSIONS: East Asians and females had a shorter NSF length and lower ratio of expected NSF to surgical defect lengths after anterior skull base reconstruction compared with the other races and with males, respectively. Anatomical differences should be considered when long NSF lengths are required, such as for anterior skull base reconstruction.

Effects of the Transfer Method and Interfacial Adhesion on the Frictional and Wear Resistance Properties of a Graphene-Coated Polymer.

Graphene is a promising candidate used to reduce friction and wear in micro- and nano-device applications owing to its superior mechanical robustness and intrinsic lubrication properties. Herein, we report the frictional and wear resistance properties of a graphene-coated polymer and how they are affected by fabrication processes. The results show that graphene deposited on a polymer substrate effectively improves both frictional and wear resistance properties, and the degree of improvement significantly depends on the graphene transfer method and interfacial adhesion between graphene and the substrate. Dry-transferred graphene showed better improvement than wet-transferred graphene, and the strong adhesion of graphene achieved by imidazole treatment aided the improvement. A combined analysis of surface morphology and scratch trace shows that the graphene transfer method and graphene adhesion dominate the structural integrity of the transferred graphene, and the graphene/substrate interfacial adhesion plays a decisive role in the improvement of both properties by suppressing the delamination of graphene from the substrate during the nanoscratch test, thereby preventing crack formation in graphene and weakening the puckering effect.

Monitoring hydrogen transport through graphene by in situ surface-enhanced Raman spectroscopy.

Exploring the atomic or molecular transport properties of two-dimensional materials is vital to understand their inherent functions and, thus, to expedite their use in various applications. Herein, a surface-enhanced Raman spectroscopy (SERS)-based in situ analytical tool for the sensitive and rapid monitoring of hydrogen transport through graphene is reported. In this method, a reducing agent, which can provide hydrogen species, and a Raman dye self-assembled on a SERS platform are separated by a graphene membrane, and the reduction of the Raman dye by hydrogen species transferred through graphene is monitored with SERS. For validating the efficacy of our method, the catalytic reduction of surface-bound 4-nitrothiophenol by sodium borohydride was chosen in this study. The experimental results distinctly demonstrate that the high sensitivity and rapid detection ability of SERS can allow the effective analysis of the hydrogen transport properties of graphene.