Optimization of hydrolysis conditions of crop straw and its effect in Chlorella sorokiniana culture.

Taking straws of corn, wheat, and millet as raw materials, we pretreated them with alkaline hydrogen peroxide, and then hydrolyzed by cellulase and xylanase. We selected the total sugar content in the hydrolysate as the indicator to evaluate the hydrolysis of the straws from three crop species, and further optimized the conditions. Then, the hydrolysates of three types of crop straws were used as carbon source for Chlorella sorokiniana culture to assess their effects on microalgal cultivation. The results showed that the optimal hydrolysis conditions for the three crop straws were identified as solid-liquid ratio of 1:15, temperature of 30 ℃, and treatment time of 12 h. Under such optimal condition, the total sugar contents increased up to 1.677, 1.412, and 1.211 g·L-1 in the corn, millet and wheat straw hydrolysate, respectively. The hydrolysates from the three crop straw could significantly increase both algal biomass and lipid content of C. sorokiniana. Corn straw hydrolysate had the best effect, with high levels of algal biomass (1.801 g·L-1) and lipid content (30.1%). Therefore, we concluded that crop straw hydrolysates as carbon source could significantly promote microalgal biomass and lipid enrichment. The results could lay the foundation for the efficient conversion and utilization of straw lignocellulose raw materials, provide new knowledge for the resource utilization of agricultural wastes, as well as the theoretical basis for the efficient cultivation of microalgae using crop straw hydrolysates.

Three-dimensional time-of-flight magnetic resonance angiography combined with high resolution T2-weighted imaging in preoperative evaluation of microvascular decompression.

BACKGROUND: Neurovascular compression (NVC) is the main cause of primary trigeminal neuralgia (TN) and hemifacial spasm (HFS). Microvascular decompression (MVD) is an effective surgical method for the treatment of TN and HFS caused by NVC. The judgement of NVC is a critical step in the preoperative evaluation of MVD, which is related to the effect of MVD treatment. Magnetic resonance imaging (MRI) technology has been used to detect NVC prior to MVD for several years. Among many MRI sequences, three-dimensional time-of-flight magnetic resonance angiography (3D TOF MRA) is the most widely used. However, 3D TOF MRA has some shortcomings in detecting NVC. Therefore, 3D TOF MRA combined with high resolution T2-weighted imaging (HR T2WI) is considered to be a more effective method to detect NVC. AIM: To determine the value of 3D TOF MRA combined with HR T2WI in the judgment of NVC, and thus to assess its value in the preoperative evaluation of MVD. METHODS: Related studies published from inception to September 2022 based on PubMed, Embase, Web of Science, and the Cochrane Library were retrieved. Studies that investigated 3D TOF MRA combined with HR T2WI to judge NVC in patients with TN or HFS were included according to the inclusion criteria. Studies without complete data or not relevant to the research topics were excluded. The Quality Assessment of Diagnostic Accuracy Studies checklist was used to assess the quality of included studies. The publication bias of the included literature was examined by Deeks' test. An exact binomial rendition of the bivariate mixed-effects regression model was used to synthesize data. Data analysis was performed using the MIDAS module of statistical software Stata 16.0. Two independent investigators extracted patient and study characteristics, and discrepancies were resolved by consensus. Individual and pooled sensitivities and specificities were calculated. The I² statistic and Q test were used to test heterogeneity. The study was registered on the website of PROSERO (registration No. CRD42022357158). RESULTS: Our search identified 595 articles, of which 12 (including 855 patients) fulfilled the inclusion criteria. Bivariate analysis showed that the pooled sensitivity and specificity of 3D TOF MRA combined with HR T2WI for detecting NVC were 0.96 [95% confidence interval (CI): 0.92-0.98] and 0.92 (95%CI: 0.74-0.98), respectively. The pooled positive likelihood ratio was 12.4 (95%CI: 3.2-47.8), pooled negative likelihood ratio was 0.04 (95%CI: 0.02-0.09), and pooled diagnostic odds ratio was 283 (95%CI: 50-1620). The area under the receiver operating characteristic curve was 0.98 (95%CI: 0.97-0.99). The studies showed no substantial heterogeneity (I2 = 0, Q = 0.001 P = 0.50). CONCLUSION: Our results suggest that 3D TOF MRA combined with HR T2WI has excellent sensitivity and specificity for judging NVC in patients with TN or HFS. This method can be used as an effective tool for preoperative evaluation of MVD.

Downregulation of Astrocyte Elevated Gene-1 Expression Combined with All-Trans Retinoic Acid Inhibits Development of Vasculogenic Mimicry and Angiogenesis in Glioma.

OBJECTIVE: This study aimed to investigate the effects of downregulating astrocyte elevated gene-1 (AEG-1) expression combined with all-trans retinoic acid (ATRA) on vasculogenic mimicry (VM) formation and angiogenesis in glioma. METHODS: U87 glioma cells were transfected with AEG-1 shRNA lentiviral vectors (U87-siAEG-1) and incubated in a medium containing 20 µmol/L ATRA. Matrigel-based tube formation assay was performed to evaluate VM formation, and the cell counting kit-8 (CCK-8) assay was used to analyze the proliferation of glioma cells in vitro. Reverse transcription-quantitative polymerase chain reaction and Western blot analysis were used to investigate the mRNA and protein expression of related genes, respectively. Glioma xenograft models were generated via subcutaneous implantation of glioma cells in nude mice. Tumor-bearing mice received an intraperitoneal injection of ATRA (10 mg/kg per day). Immunohistochemistry was used to evaluate the expression of related genes and the microvessel density (MVD) in glioma xenograft models. CD34/periodic acid-Schiff double staining was performed to detect VM channels in vivo. The volume and weight of tumors were measured, and a tumor growth curve was drawn to evaluate tumor growth. RESULTS: A combination of ATRA intervention and downregulation of AEG-1 expression significantly inhibited the proliferation of glioma cells in vitro and glioma VM formation in vitro and in vivo. It also significantly decreased MVD and inhibited tumor growth. Further, the expression levels of matrix metalloproteinase (MMP)-2, MMP-9, vascular endothelial-cadherin (VE-cadherin), and vascular endothelial growth factor (VEGF) in glioma significantly decreased in vivo and in vivo. CONCLUSION: Hence, a combinatorial approach might be effective in treating glioma through regulating MMP-2, MMP-9, VEGF, and VE-cadherin expression.

Modified surgical method of supra- and infratentorial epidural hematoma and the related anatomical study of the squamous part of the occipital bone.

BACKGROUND: Supra- and infratentorial acute epidural hematoma (SIEDH) is a common posterior cranial fossa epidural hematoma located at the inner surface of the squamous part of the occipital bone (SOB). Traditionally, surgical treatment of the SIEDH requires a combined supra-infratentorial craniotomy. AIM: To analyze the morphological characteristics of the SOB and introduce a single supratentorial craniotomy for SIEDH. METHODS: Skull computed tomography (CT) scan data from 32 adult patients were collected from January 1, 2019 to January 31, 2020. On the median sagittal plane of the CT scan, the angle of the SOB (ASOB) was defined by two lines: Line A was defined from the lambdoid suture (LambS) to the external occipital protuberance (EOP), while line B was defined from the EOP to the posterior edge of the foramen magnum (poFM). The operative angle for the SIEDH (OAS) from the supra- to infratentorial epidural space was determined by two lines: The first line passes from the midpoint between the EOP and the LambS to the poFM, while the second line passes from the EOP to the poFM. The ASOB and OAS were measured and analyzed. RESULTS: Based on the anatomical study, a single supratentorial craniotomy was performed in 8 patients with SIEDH. The procedure and the results of the modified surgical method were demonstrated in detail. For males, the ASOB was 118.4 ± 4.7 and the OAS was 15.1 ± 1.8; for females, the ASOB was 130.4 ± 5.1 and the OAS was 12.8 ± 2.0. There were significant differences between males and females both in ASOB and OAS. The smaller the ASOB was, the larger the OAS was. The bone flaps in 8 patients were designed above the transverse sinus intraoperatively, and the SIEDH was completely removed without suboccipital craniotomy. The SOB does not present as a single straight plane but bends at an angle around the EOP and the superior nuchal lines. The OAS was negatively correlated with the ASOB. CONCLUSION: The single supratentorial craniotomy for SIEDH is reliable and effective.

Combined elevation of TRIB2 and MAP3K1 indicates poor prognosis and chemoresistance to temozolomide in glioblastoma.

INTRODUCTION: Glioblastoma (GBM) is the most lethal primary malignant brain tumor in adults with poor survival due to acquired therapeutic resistance and rapid recurrence. Currently, the standard clinical strategy for glioma includes maximum surgical resection, radiotherapy, and temozolomide (TMZ) chemotherapy; however, the median survival of patients with GBM remains poor despite these comprehensive therapies. Therefore, the identification of new prognostic biomarkers is urgently needed to evaluate the malignancy and long-term outcome of glioma. AIMS: To further investigate prognostic biomarkers and potential therapeutic targets for GBM. RESULTS: In this study, we identified tribbles pseudokinase 2 (TRIB2) as one of the genes that is most correlated with pathological classification, radioresistance, and TMZ resistance in glioma. Additionally, the expression of mitogen-activated protein kinase kinase kinase 1 (MAP3K1) showed a strong correlation with TRIB2. Moreover, a combined increase in TRIB2 and MAP3K1 was observed in GBM and indicated a poor prognosis of patients with glioma. Finally, enriched TRIB2 expression and MAP3K1 expression were shown to be associated with resistance to TMZ and radiotherapy. CONCLUSION: Combined elevation of TRIB2 and MAP3K1 could be novel prognostic biomarkers and potential therapeutic targets to evaluate the malignancy and long-term outcomes of GBM.

PDZ-Binding Kinase-Dependent Transcriptional Regulation of CCNB2 Promotes Tumorigenesis and Radio-Resistance in Glioblastoma.

Increasing evidence has indicated that PDZ binding kinase (PBK) promotes proliferation, invasion, and therapeutic resistance in a variety of cancer types. However, the physiological function and therapy-resistant role of PBK in GBM remain underexplored. In this study, PBK was identified as one of the most therapy-resistant genes with significantly elevated expression level in GBM. Moreover, the high expression level of PBK was essential for GBM tumorigenesis and radio-resistance both in vitro and in vivo. Clinically, aberrant activation of PBK was correlated with poor clinical prognosis. In addition, inhibition of PBK dramatically enhanced the efficacy of radiation therapy in GBM cells. Mechanically, PBK-dependent transcriptional regulation of CCNB2 was critical for tumorigenesis and radio-resistance in GBM cells. Collectively, PBK promotes tumorigenesis and radio-resistance in GBM and may serve as a novel therapeutic target for GBM treatment.

Downregulation of AIF-2 Inhibits Proliferation, Migration, and Invasion of Human Glioma Cells via Mitochondrial Dysfunction.

Glioma remains the leading cause of brain tumor-related death worldwide. Apoptosis inducing factor (AIF) is a family of mitochondrial oxidoreductases that play important roles in mitochondrial metabolism and redox control. AIF-1 has been demonstrated to exert cell-killing effect via apoptosis in cancer cells, whereas the role of AIF-2 in cancer cells has not been determined. This study aimed to investigate the role of AIF-2 in human glioma cells. We found that AIF-2 was upregulated in human glioma tissues and cell lines, especially in U251 cells. Downregulation of AIF-2 using specific siRNA (Si-AIF-2) significantly reduced cell proliferation, induced G1 cell cycle arrest and differently regulated the expression of cell cycle regulator proteins in U251 cells. In addition, the results of Matrigel invasion assay and live-cell tracking assay showed that knockdown of AIF-2 inhibited cell invasion and migration. The results of immunocytochemistry indicated that knockdown of AIF-2 significantly attenuated the nuclear translocation of AIF-1, which was confirmed by western blot analysis. Furthermore, downregulation of AIF-2 resulted in mitochondrial dysfunction in U251 cells, as evidenced by reduced mitochondrial membrane potential (MMP), mitochondrial complex I activity, and mitochondrial Ca2+ buffering capacity. In conclusion, we found that AIF-2 plays a key role in promoting cell proliferation, invasion, and migration via regulating AIF-1-related mitochondrial cascades. Downregulation of the candidate oncogene AIF-2 might constitute a strategy to kill human glioma cells.

Salvianolic acid B renders glioma cells more sensitive to radiation via Fis-1-mediated mitochondrial dysfunction.

Glioma remains the leading cause of brain tumor-related death worldwide, and radiation is a standard adjuvant therapy with proven efficacy. Salvianolic acid B (SalB), a bioactive compound isolated from Radix Salviae, has been shown to exert anti-cancer effects in many cancer cell lines, including glioma. This study aimed to investigate whether SalB could affect response to radiation in human glioma cells. We found that SalB decreased cell viability of U87 cells in a-dose-dependent manner. A subthreshold dose of SalB at 0.5 µM, which had no effect on cell viability and apoptosis, significantly increased radiation sensitivity of U87 cells in a dose- and time-dependent manner, but had no effect on sensitivity to temozolomide (TMZ). Similar results were also observed in human glioma U373 cells. In addition, SalB aggravated the radiation-induced apoptosis and mitochondrial dysfunction, as measured by mitochondrial Ca2+ buffering capacity and mitochondrial swelling. SalB treatment markedly promoted mitochondrial fission and differently regulated the expression of fission proteins. Furthermore, downregulation of the fission protein Fis-1 using siRNA was found to partially reversed the SalB-induced effects on cell viability, apoptosis and mitochondrial fission in U87 cells. In conclusion, our results suggest that a subthreshold dose of SalB renders glioma cells more sensitive to radiation via Fis-1-mediated mitochondrial dysfunction, and radiotherapy combined with SalB might be a novel treatment for glioma patients.

Localization of Anterosuperior Point of Transverse-sigmoid Sinus Junction Using a Reference Coordinate System on Lateral Skull Surface.

BACKGROUND: During craniotomies using the transpetrosal-presigmoid approach, exposure of the sigmoid sinus remains an essential but hazardous step. In such procedures, accurate localization of the anterosuperior point of the transverse-sigmoid sinus junction (ASTS) is very important for reducing surgical morbidity. This study aimed to create an accurate and practical method for identifying the ASTS. METHODS: On the lateral surfaces of 40 adult skulls (19 male skulls and 21 female skulls), a rectangular coordinate system was defined to measure the x and y coordinates of two points: the ASTS and the squamosal-parietomastoid suture junction (SP). With the coordinate system, the distribution characteristics of the ASTS were statistically analyzed and the differences between the ASTS and SP were investigated. RESULTS: For ASTS-x, significant differences were found in different sides (P = 0.020); the ASTS-x in male skulls was significantly higher on the right side (P = 0.017); there was no significant difference between the sides in female skulls. There were no significant differences in gender or interaction of gender and side for ASTS-x, and for ASTS-y, there were no significant differences in side, gender, or interaction of gender and side. For both sides combined, the mean ASTS-x was significantly higher than the mean SP-x (P = 0.003) and the mean ASTS-y was significantly higher than the mean SP-y (P = 0.011). CONCLUSIONS: This reference coordinate system may be an accurate and practical method for identifying the ASTS during presigmoid craniotomy. The SP might be difficult to find during presigmoid craniotomy and, therefore, it is not always a reliable landmark for defining the ASTS.

A novel reference coordinate system to locate the inferomedial point of the transverse-sigmoid sinus junction.

BACKGROUND: A coordinate system was previously developed to identify landmarks on the skull surface to help locate the transverse-sigmoid sinus junction in order to reduce surgical morbidity in retrosigmoid craniotomy; however, in practice we found that this system has important flaws. OBJECTIVE: To develop and evaluate a novel reference coordinate system to precisely locate the inferomedial point of the transverse-sigmoid sinus junction (IMTS) and evaluate the effect of gender and skull side (left or right). METHODS: Forty-two adult skulls (84 sides) were obtained for analyses. The X-axis was defined by point A (where the upper edge of the zygomatic arch joins with the frontal process of the zygomatic bone) and point B (where the upper edge of the zygomatic arch blends posterosuperiorly into the supramastoid crest). The Y-axis was defined by the line perpendicular to the X-axis and extending across the tip of the mastoid. The x and y coordinates of IMTS (IMTS-x and IMTS-y) were measured in this coordinate system. RESULTS: There were 20 male skulls and 22 female skulls. The mean IMTS-x measurements were significantly higher on the right side compared with the left side in both males and females. For the left skull side, the mean IMTS-y measurements were significantly lower in females compared with males. CONCLUSION: This novel reference coordinate system may be a reliable and practical method for identifying the IMTS during retrosigmoid craniotomy. There are significant differences in location of the axes with regard to gender and skull side.