Search

Abstract Glioma, a malignant and infiltrative neoplasm of the central nervous system, poses a significant threat due to its high mortality rates. Branched-chain amino acid transaminase 1 (BCAT1), a key enzyme in branched-chain amino acid (BCAA) catabolism, exhibits elevated expression in gliomas and correlates strongly with poor prognosis. Nonetheless, the regulatory mechanisms underlying this increased BCAT1 expression remains incompletely understood. In this study, we reveal that ubiquitination at Lys360 facilitates BCAT1 degradation, with low ubiquitination levels contributing to high BCAT1 expression in glioma cells. The Carboxyl terminus of Hsc70-interacting protein (CHIP), an E3 ubiquitin ligase, interacts with BCAT1 via its coiled-coil (CC) domain, promoting its K48-linkage ubiquitin degradation through proteasomal pathway. Moreover, CHIP-mediated BCAT1 degradation induces metabolic reprogramming, and impedes glioma cell proliferation and tumor growth both in vitro and in vivo. Furthermore, a positive correlation is observed between low CHIP expression, elevated BCAT1 levels, and unfavorable prognosis among glioma patients. Additionally, we show that the CHIP/BCAT1 axis enhances glioma sensitivity to temozolomide by reducing glutathione (GSH) synthesis and increasing oxidative stress. These findings underscore the critical role of CHIP/BCAT1 axis in glioma cell proliferation and temozolomide sensitivity, highlighting its potential as a diagnostic marker and therapeutic target in glioma treatment.

Abstract Objective Although blood urea nitrogen (BUN) has a crucial impact on many diseases, its effect on outcomes in patients with hyperlipidemia remains unknown. The study aimed to investigate the relationships between BUN levels and all-cause and cardiovascular disease (CVD) mortality in individuals with hyperlipidemia. Methods This analysis comprised 28,122 subjects with hyperlipidemia from the National Health and Nutrition Examination Survey (NHANES) spanning 1999 to 2018. The risk of BUN on mortality was evaluated using weighted Cox regression models. Additionally, to illustrate the dose-response association, the restricted cubic spline (RCS) was used. Results During the observation period, 4276 participant deaths were recorded, of which 1206 were due to CVD. Compared to patients with hyperlipidemia in the third BUN quintile, the hazard ratios (HRs) for all-cause mortality were 1.26 (95% CIs: 1.09, 1.45) and 1.22 (95% CIs: 1.09, 1.37) for patients in the first and fifth quintiles of BUN, respectively. The HRs for CVD mortality among patients in the fifth quintile of BUN were 1.48 (95% CIs: 1.14, 1.93). BUN levels were found to have a U-shaped association with all-cause mortality and a linear association with CVD mortality using restricted triple spline analysis. Conclusions This study revealed that both low and high BUN levels in patients with hyperlipidemia are associated with heightened all-cause mortality. Furthermore, elevated BUN levels are also associated with increased CVD mortality. The findings indicate that patients with hyperlipidemia may face an elevated risk of death if they have abnormal BUN levels.

The digital correlator is one of the most crucial data processing components of a radio telescope array. With the scale of radio interferometeric array growing, many efforts have been devoted to developing a cost-effective and scalable correlator in the field of radio astronomy. In this paper, a 192-input digital correlator with six CASPER ROACH2 boards and seven GPU servers has been deployed as the digital signal processing system for Tianlai cylinder pathfinder located in Hongliuxia observatory. The correlator consists of 192 input signals (96 dual-polarization), 125-MHz bandwidth, and full-Stokes output. The correlator inherits the advantages of the CASPER system, for example, low cost, high performance, modular scalability, and a heterogeneous computing architecture. With a rapidly deployable ROACH2 digital sampling system, a commercially expandable 10 Gigabit switching network system, and a flexible upgradable GPU computing system, the correlator forms a low-cost and easily-upgradable system, poised to support scalable large-scale interferometeric array in the future.

The human eye is susceptible to various disorders that affect its structure or function, including glaucoma, age-related macular degeneration (AMD) and diabetic retinopathy (DR). Mitochondrial dysfunction has been identified as a critical factor in the pathogenesis and progression of eye disorders, making it a potential therapeutic target in the clinic. Natural products have been used in traditional medicine for centuries and continue to play a significant role in modern drug development and clinical therapeutics. Recently, there has been a surge in research exploring the efficacy of natural products in treating eye disorders and their underlying physiological mechanisms. This review aims to discuss the involvement of mitochondrial dysfunction in eye disorders and summarize the recent advances in the application of natural products targeting mitochondria. In addition, we describe the future perspective and challenges in the development of mitochondria-targeting natural products.

BackgroundThe neutrophil-to-lymphocyte ratio (NLR) and lactate dehydrogenase (LDH) level are inflammatory markers related to tumor growth and metabolism. This study investigated the value of preoperative NLR, LDH and the combination of NLR and LDH (NLR-LDH) for predicting colorectal cancer liver metastasis (CRLM) and tumor prognosis in the early stages of colorectal cancer (CRC).Materials and methodsThree hundred patients undergoing CRC resection were included. Logistic regression analysis was used to estimate the correlation between CRLM time and inflammatory markers, and Kaplan–Meier survival and Cox regression analyses were used to estimate overall survival (OS). Forest plots were prepared based on the multivariate Cox analysis model and evaluated by receiver operating characteristic (ROC) curve analysis.ResultsThe NLR cut-off value was 2.071 according to the ROC curve. The multivariate analysis showed that the elevated LDH level and a high NLR-LDH level were independent predictors of synchronous CRLM and OS (p

Abstract Background and aims Cholecystectomy is performed for most gallbladder polyps (GPs). However, cholecystectomy results concerning complications in some patients. For benign GPs, adoption of gallbladder-preserving surgery is worth to recommend. We describe our experiences performing gallbladder-preserving polypectomy for GPs by embryonic-natural orifice transumbilical endoscopic surgery (E-NOTES) with a gastric endoscopy. Methods This is a retrospective study of patients with GPs who underwent gallbladder-preserving polypectomy by E-NOTES with a gastric endoscopy from April 2018 to September 2019 in our hospital. The operative time, intraoperative hemorrhage, intraoperative and postoperative complications, gallbladder emptying function were obtained and analyzed. Results The procedure was performed successfully in all 12 patients with 5 cases of single polyp and 7 cases of multiple polyps. The range of GPs size was 2 mm to 15 mm. The mean operation time was (95.33 ± 23.08) minutes (55–135 min). There were no adverse events including heavy bleeding, mortality and conversion to open surgery during operation. All patients were discharged in 4–5 days after surgery without postoperative complications such as delayed bleeding, fever, peritonitis, intra-abdominal abscess and abdominal wall incisional hernia. All patients were followed up at 1, 3, 6, and 12 months postoperation who had almost no visible incision on the umbilical region, no recurrent GPs. The gallbladder emptying function decreased one month after surgery, and gradually improved 3, 6 and 12 months after surgery. Conclusion E-NOTES gallbladder-preserving polypectomy is a safe and effective option for patients with GPs and is close to scar-free surgery which can be performed in routine clinical practice.

Gastric cancer (GC) is one of the most common tumors worldwide, and cisplatin is a standard chemotherapeutic reagent for GC treatment. However, chemoresistance is an inherent challenge which limits its application and effectiveness in clinic. This study aims to investigate the mechanism of metformin-induced cisplatin resistance in GC. Intriguingly, the upregulation of mitophagy markers, mitochondrial fission, autophagy and mitophagosome were observed in SGC-7901/DDP cells compared to those in the SGC-7901 cells. Treatment with metformin significantly increased mitochondrial fission and mitophagy in both AGS and SGC-7901 cells, resulting in decreased ATP production, which unexpectedly protected GC cells against the cytotoxicity of cisplatin. In contrast, application of Chloroquine and 3-methyladenine, two inhibitors of autophagy, significantly alleviated the protective effect of metformin on SGC-7901 and AGS cells against cytotoxicity of cisplatin. Moreover, metformin also stimulated the phosphorylation of AMPK (Thr172) and increased the expression of mitophagy markers including Parkin and PINK1 in the AMPK signaling-dependent manner. Consistently, the cell viability and cell apoptosis assay showed that metformin-induced cisplatin resistance was prevented by knockdown of AMPKα1. Taken together, all data in this study indicate that metformin induced AMPK activation and PINK1/Parkin dependent mitophagy, which may contribute to the progression of cisplatin resistance in GC.

Nonalcoholic fatty liver disease (NAFLD) is a prevalent hepatic disease in the world. Disorders of branched chain amino acid (BCAA) metabolism is involved in various diseases. In this study, we aim to explore the role of BCAA metabolism in the development of NAFLD and the protective effect of BCATc Inhibitor 2, an inhibitor of cytosolic branched chain amino acid transaminase, against NAFLD as well as its underlying mechanism. It was found that oleic acid induced lipid accumulation and apoptosis in HepG2 and LO2 cells. Supplementation of BCAAs further aggravated oleic acid-induced lipid accumulation and apoptosis. In contrast, treatment of BCATc Inhibitor 2 ameliorated oleic acid-induced lipid accumulation and apoptosis. Molecularly, supplementation of BCAAs or treatment of BCATc Inhibitor 2 up-regulated or down-regulated the expression of SREBP1 and lipogenesis-related genes without affecting lipolysis-related genes. BCATc Inhibitor 2 maintained mitochondrial function by ameliorating oleic acid-induced mitochondrial ROS generation and mitochondrial membrane potential disruption. In addition, BCATc Inhibitor 2 treatment alleviated oleic acid-induced activation of JNK and AKT signaling pathway and Bcl2/Bax/Caspase axis. In conclusion, our results indicate BCAA metabolism is involved in NAFLD and BCATc Inhibitor 2 protects against oleic acid-induced lipid accumulation and apoptosis. These findings suggest that BCATc Inhibitor 2 is a promising candidate drug for the treatment of NAFLD.

Sloanea hemsleyana is a potential commercial and oil tree species. This study is the first to report and analyze complete chloroplast genome sequences of S. hemsleyana as a genomic resource for conservation purposes. The chloroplast genome is 158,085 bp in length and consisted of a large single-copy (LSC) region (88,446 bp), and a small single-copy (SSC) region (17,659 bp), separated by a pair of inverted repeats (IR) regions (25,990 bp). It contains 108 genes, with 74 protein-coding genes, 30 tRNA genes, and 4 rRNA genes. Phylogenetic analysis revealed that S. hemsleyana was most closely related to S. sinensis.

In combination with studies of post-mortem Parkinson's disease (PD) brains, pharmacological and genetic models of PD have suggested that two fundamental interacting cellular processes are impaired – proteostasis and mitochondrial respiration. We have re-examined the role of mitochondrial dysfunction in lymphoblasts isolated from individuals with idiopathic PD and an age-matched control group. As previously reported for various PD cell types, the production of reactive oxygen species (ROS) by PD lymphoblasts was significantly elevated. However, this was not due to an impairment of mitochondrial respiration, as is often assumed. Instead, basal mitochondrial respiration and ATP synthesis are dramatically elevated in PD lymphoblasts. The mitochondrial mass, genome copy number and membrane potential were unaltered, but the expression of indicative respiratory complex proteins was also elevated. This explains the increased oxygen consumption rates by each of the respiratory complexes in experimentally uncoupled mitochondria of iPD cells. However, it was not attributable to increased activity of the stress- and energy-sensing protein kinase AMPK, a regulator of mitochondrial biogenesis and activity. The respiratory differences between iPD and control cells were sufficiently dramatic as to provide a potentially sensitive and reliable biomarker of the disease state, unaffected by disease duration (time since diagnosis) or clinical severity. Lymphoblasts from control and PD individuals thus occupy two distinct, quasi-stable steady states; a ‘normal’ and a ‘hyperactive’ state characterized by two different metabolic rates. The apparent stability of the ‘hyperactive’ state in patient-derived lymphoblasts in the face of patient ageing, ongoing disease and mounting disease severity suggests an early, permanent switch to an alternative metabolic steady state. With its associated, elevated ROS production, the ‘hyperactive’ state might not cause pathology to cells that are rapidly turned over, but brain cells might accumulate long-term damage leading ultimately to neurodegeneration and the loss of mitochondrial function observed post-mortem. Whether the ‘hyperactive’ state in lymphoblasts is a biomarker specifically of PD or more generally of neurodegenerative disease remains to be determined.

The fragile X premutation (PM) allele contains a CGG expansion of 55–200 repeats in the FMR1 gene’s promoter. Male PM carriers have an elevated risk of developing neurological and psychiatric changes, including an approximately 50% risk of the fragile X-associated tremor/ataxia syndrome (FXTAS). The aim of this study was to assess the relationships of regional white matter hyperintensities (wmhs) semi-quantitative scores, clinical status, motor (UPDRS, ICARS, Tremor) scales, and cognitive impairments, with FMR1-specific genetic changes, in a sample of 32 unselected male PM carriers aged 39–81 years. Half of these individuals were affected with FXTAS, while the non-FXTAS group comprised subcategories of non-affected individuals and individuals affected with non-syndromic changes. The dynamics of pathological processes at the cellular level relevant to the clinical status of PM carriers was investigated using the enzyme AMP-activated protein kinase (AMPK), which is a highly sensitive cellular stress-sensing alarm protein. This enzyme, as well as genetic markers – CGG repeat number and the levels of the FMR1 mRNA – were assessed in blood lymphoblasts. The results showed that the repeat distribution for FXTAS individuals peaked at 85–90 CGGs; non-FXTAS carriers were distributed within the lowest end of the PM repeat range, and non-syndromic carriers assumed an intermediate position. The size of the CGG expansion was significantly correlated, across all three categories, with infratentorial and total wmhs and with all motor scores, and the FMR1 mRNA levels with all the wmh scores, whilst AMPK activity showed considerable elevation in the non-FXTAS combined group, decreasing in the FXTAS group, proportionally to increasing severity of the wmhs and tremor/ataxia. We conclude that the size of the CGG expansion relates to the risk for FXTAS, to severity of infratentorial wmhs lesions, and to all three motor scale scores. FMR1 mRNA shows a strong association with the extent of wmhs, which is the most sensitive marker of the pathological process. However, the AMPK activity findings – suggestive of a role of this enzyme in the risk of FXTAS – need to be verified and expanded in future studies using larger samples and longitudinal assessment.

Neurogenic pulmonary edema caused by severe brainstem encephalitis is the leading cause of death in young children infected by Enterovirus 71 (EV71). However, no pulmonary lesions have been found in EV71-infected transgenic or non-transgenic mouse models. Development of a suitable animal model is important for studying EV71 pathogenesis and assessing effect of therapeutic approaches. We had found neurological disorders in EV71-induced young gerbils previously. Here, we report severe pulmonary lesions characterized with pulmonary congestion and hemorrhage in a gerbil model for EV71 infection. In the EV71-infected gerbils, six 21-day-old or younger gerbils presented with a sudden onset of symptoms and rapid illness progression after inoculation with 1×105.5 TCID50 of EV71 via intraperitoneal (IP) or intramuscular (IM) route. Respiratory symptoms were observed along with interstitial pneumonia, pulmonary congestion and extensive lung hemorrhage could be detected in the lung tissues by histopathological examination. EV71 viral titer was found to be peak at late stages of infection. EV71-induced pulmonary lesions, together with severe neurological disorders were also observed in gerbils, accurately mimicking the disease process in EV71-infected patients. Passive transfer with immune sera from EV71 infected adult gerbils with a neutralizing antibody (GMT=89) prevented severe pulmonary lesion formation after lethal EV71 challenge. These results establish this gerbil model as a useful platform for studying the pathogenesis of EV71-induced pulmonary lesions, immunotherapy and antiviral drugs.

After demonstrating four basic properties a multi-period risk measure should satisfy, a class of generalized convex multi-period risk measures is defined, which improves and extends existing coherent and convex multi-period risk measures. With respect to this kind of generalized convex multi-period risk measure, the equivalence among different notions of time consistency of risk measure is established. Furthermore, by introducing a fair property that any sophisticated multi-period risk measure should satisfy, we show that if the multi-period risk measure is time consistent, then optimal decisions derived under this risk measure also satisfy the time consistency of optimal policy. Finally, we present the concrete structure of the time consistent generalized convex multi-period risk measure, and illustrate through several examples how to construct time consistent generalized convex multi-period risk measures from existing single-period risk measures. [ABSTRACT FROM AUTHOR]

This paper investigates a time consistent multiperiod mean-variance (MV) portfolio selection problem under the Markov regime-switching framework. We use a vector auto-regression model to forecast the values of market factors and then predict the returns of risky assets by using a regime-dependent linear multifactor model. By introducing the notion of separable expected conditional mapping, we construct a time consistent multiperiod MV model with regime switching. Under the self-financing constraint, we derive an analytical optimal investment policy satisfying time consistency and the corresponding MV efficient frontier by using dynamic programming. Empirical results are provided to illustrate the reasonability and practicality of the proposed new model and the derived explicit investment strategy. Especially, we find that the investor invests more in risky assets under a bull market than that under a consolidation market or a bear market; the MV efficient frontier under a bull market is much superior to those determined under a consolidation market and a bear market. [ABSTRACT FROM AUTHOR]

Aim Of Study: The aim was to explore the structure and functions of new target spot c-Myc target from laryngeal cancer cell. (MTLC) of c-Myc gene.Methods: This study adopted bioinformatic methods to analyze the physicochemical property, secondary structure, hydrophobic region, a transmembrane region, and prediction of functions.Results: The results showed that the whole length of the open reading frames was 708 bp, coding was 235 amino acids. This protein was a basic protein possessed two transmembrane structures and weight was about 26592.5 Da. The main elements of secondary structure were alpha-helix and random coil. MTLC was a membrane constitutive protein that possessed signal transduction and regulation may locate on karyotheca as results of subcellular localization and function prediction.Conclusion: This study has provided the theoretical basis for the further discussion of the effect and mechanism of action of MTLC in the occurrence of laryngeal cancer. [ABSTRACT FROM AUTHOR]