Evidence that spatial scale and environment factors explain grassland community assembly in woodland-grassland ecotones.

How communities of living organisms assemble has long been a central question in ecology. The impact of habitat filtering and limiting similarity on plant community structures is well known, as both processes are influenced by individual responses to environmental fluctuations. Yet, the precise identifications and quantifications of the potential abiotic and biotic factors that shape community structures at a fine scale remains a challenge. Here, we applied null model approaches to assess the importance of habitat filtering and limiting similarity at two spatial scales. We used 63 natural vegetation plots, each measuring 5 × 5 m, with three nested subplots measuring 1 × 1 m, from the 2021 field survey, to examine the alpha diversity as well as beta diversity of plots and subplots. Linear mixed-effects models were employed to determine the impact of environmental variables on assembly rules. Our results demonstrate that habitat filtering is the dominant assembly rules at both the plot and subplot levels, although limiting similarity assumes stronger at the subplot level. Plot-level limiting similarity exhibited a positive association with fine-scale partitioning, suggesting that trait divergence originated from a combination of limiting similarity and spatial partitioning. Our findings also reveal that the community assembly varies more strongly with the mean annual temperature gradient than the mean annual precipitation. This investigation provides a pertinent illustration of non-random assembly rules from spatial scale and environmental factors in plant communities in the loess hilly region. It underscores the critical influence of spatial and environmental constraints in understanding the assembly of plant communities.

Mechanisms, combination therapy, and biomarkers in cancer immunotherapy resistance.

Anti-programmed death 1/programmed death ligand 1 (anti-PD-1/PD-L1) antibodies exert significant antitumor effects by overcoming tumor cell immune evasion and reversing T-cell exhaustion. However, the emergence of drug resistance causes most patients to respond poorly to these immune checkpoint inhibitors (ICIs). Studies have shown that insufficient T-cell infiltration, lack of PD-1 expression, deficient interferon signaling, loss of tumor antigen presentation, and abnormal lipid metabolism are all considered to be closely associated with immunotherapy resistance. To address drug resistance in tumor immunotherapy, a lot of research has concentrated on developing combination therapy strategies. Currently, ICIs such as anti-PD-1 /PD-L1 antibody combined with chemotherapy and targeted therapy have been approved for clinical treatment. In this review, we analyze the mechanisms of resistance to anti-PD-1/PD-L1 therapy in terms of the tumor microenvironment, gut microbiota, epigenetic regulation, and co-inhibitory immune checkpoint receptors. We also discuss various promising combination therapeutic strategies to address resistance to anti-PD-1/PD-L1 drugs, including combining these therapies with traditional Chinese medicine, non-coding RNAs, targeted therapy, other ICIs, and personalized cancer vaccines. Moreover, we focus on biomarkers that predict resistance to anti-PD-1/PD-L1 therapy as well as combination therapy efficacy. Finally, we suggest ways to further expand the application of immunotherapy through personalized combination strategies using biomarker systems.

Prevention and management of enteral nutrition-related diarrhea among adult inpatients: a best practice implementation project.

INTRODUCTION: Diarrhea, the most common complication for patients during enteral nutrition, poses a range of risks and care burdens. Medical staff are aware of the importance of proactively preventing and managing enteral nutrition-related diarrhea. However, clinical prevention and management methods are not standardized, and the scientific basis and effectiveness of these methods need to be further verified. OBJECTIVES: This project aimed to promote evidence-based practices for the prevention and management of enteral nutrition-related diarrhea among adult inpatients in a public tertiary hospital in China. METHODS: This project was guided by the JBI Evidence Implementation Framework and used the JBI Practical Application of Clinical Evidence System (PACES) and the JBI Getting Research into Practice (GRiP) tools. Twelve audit criteria were developed to conduct a baseline audit to measure compliance with best practices. A barrier analysis was conducted, and strategies were implemented to overcome the barriers. The project was finalized with a follow-up audit to determine any changes in compliance with best practices. RESULTS: The overall compliance rate for the audit criteria increased from 27.37% at baseline to 89.62% in the follow-up audit, with six criteria achieving a compliance rate of 100%. CONCLUSIONS: The implementation of evidence-based practices can effectively narrow the gap between current practice and best practice. This project improved the ability of medical staff to prevent and manage enteral nutrition-related diarrhea, as well as promoting evidence-based practice in the hospital. SPANISH ABSTRACT: http://links.lww.com/IJEBH/A168.

HKDC1, a target of TFEB, is essential to maintain both mitochondrial and lysosomal homeostasis, preventing cellular senescence.

Mitochondrial and lysosomal functions are intimately linked and are critical for cellular homeostasis, as evidenced by the fact that cellular senescence, aging, and multiple prominent diseases are associated with concomitant dysfunction of both organelles. However, it is not well understood how the two important organelles are regulated. Transcription factor EB (TFEB) is the master regulator of lysosomal function and is also implicated in regulating mitochondrial function; however, the mechanism underlying the maintenance of both organelles remains to be fully elucidated. Here, by comprehensive transcriptome analysis and subsequent chromatin immunoprecipitation-qPCR, we identified hexokinase domain containing 1 (HKDC1), which is known to function in the glycolysis pathway as a direct TFEB target. Moreover, HKDC1 was upregulated in both mitochondrial and lysosomal stress in a TFEB-dependent manner, and its function was critical for the maintenance of both organelles under stress conditions. Mechanistically, the TFEB-HKDC1 axis was essential for PINK1 (PTEN-induced kinase 1)/Parkin-dependent mitophagy via its initial step, PINK1 stabilization. In addition, the functions of HKDC1 and voltage-dependent anion channels, with which HKDC1 interacts, were essential for the clearance of damaged lysosomes and maintaining mitochondria-lysosome contact. Interestingly, HKDC1 regulated mitophagy and lysosomal repair independently of its prospective function in glycolysis. Furthermore, loss function of HKDC1 accelerated DNA damage-induced cellular senescence with the accumulation of hyperfused mitochondria and damaged lysosomes. Our results show that HKDC1, a factor downstream of TFEB, maintains both mitochondrial and lysosomal homeostasis, which is critical to prevent cellular senescence.

Climates and associated factors for evidence-based practice implementation among nurses: a cross-sectional study.

BACKGROUND: The organizational climate that fosters and supports the implementation of evidence is a key factor influencing the effective implementation of evidence-based practice (EBP). Nurses, being the largest group of medical staff, play a crucial role in EBP implementation. The perception of the climate for EBP implementation among nurses in their organizations is unknown, especially among Chinese nurses. AIMS: To clarify the implementation climate of EBP among Chinese nurses and identify the factors associated with the implementation and development of evidence-based nursing practices. METHODS: This study employed a descriptive cross-sectional study design. From March 2023 to April 2023, a sample of nurses (n = 1260) from two Tertiary care hospitals in central China were selected and surveyed by self-designed social-demographic questionnaire and Implementation Climate Scale. Multiple linear stepwise regression analysis was conducted to determine the predictors of implementation climate. RESULTS: The nurses achieved a mean ICS score of 59.10 ± 11.22, with mean scores exceeding 3 points for each sub-dimension and item. In the results of multiple linear regression, income satisfaction, implementation of evidence-based nursing practice project(s) within the unit, experience of evidence-based nursing practice during working life, and specific training or courses in evidence-based nursing practice were predictors of ICS. Of these, income satisfaction was the most significant predictor. These factors could explain 17.5% of the total variance in implementation climate. CONCLUSION: The climate for implementing EBP in Chinese nursing organizations was relatively strong. Nursing managers can enhance the climate for implementing EBP in their organizations by actively improving salary and enhancing EBP-related trainings and practices. RELEVANCE TO CLINICAL PRACTICE: Understanding nurses' perceptions of the EBP implementation climate in their organizations can help to identify specific barriers and facilitators to the development of EBP and facilitate its successful implementation. PATIENT OR PUBLIC CONTRIBUTION: Clinical nurses were involved in data collection and completed the questionnaires on EBP implementation climate.

Connecting the mechanisms of tumor sex differences with cancer therapy.

Sex differences in cancer incidence and survival are constant and pronounced globally, across all races and all age groups of cancer types. In 2016, after the National Institutes of Health proposed a policy of utilizing sex as a biological variable, researchers started paying more attention to the molecular mechanisms behind gender variations in cancer. Historically, most previous studies investigating sex differences have been centered on gonadal sex hormones. Nevertheless, sex differences also involve genetic and molecular pathways that run throughout the entire process of cancer cell proliferation, metastasis, and treatment response, in addition to sex hormones. In particular, there is significant gender dimorphism in the efficacy and toxicity of oncology treatments, including conventional radiotherapy and chemotherapy, as well as the emerging targeted therapies and immunotherapy. To be clear, not all mechanisms will exhibit gender bias, and not all gender bias will affect cancer risk. Our goal in this review is to discuss some of the significant sex-related changes in fundamental cancer pathways. To this purpose, we summarize the differential impact of gender on cancer development in three dimensions: sex hormones, genetics, and epigenetics, and focus on current hot subjects including tumor suppressor function, immunology, stem cell renewal, and non-coding RNAs. Clarifying the essential mechanisms of gender differences will help guide the clinical treatment of both sexes in tumor radiation and chemotherapy, medication therapy with various targets, immunotherapy, and even drug development. We anticipate that sex-differentiated research will help advance sex-based cancer personalized medicine models and encourage future basic scientific and clinical research to take sex into account.

Production of species-specific anthocyanins through an inducible system in plant hairy roots.

Anthocyanins are widely distributed pigments in flowering plants with red, purple or blue colours. Their properties in promoting heath make anthocyanins perfect natural colourants for food additives. However, anthocyanins with strong colour and stability at neutral pH, suitable as food colourants are relatively rare in nature. Acylation increases anthocyanin stability and confers bluer colour. In this study, we isolated two anthocyanin regulators SbMyb75 and SbDel from S. baicalensis, and showed that constitutive expression of the two TFs led to accumulation of anthocyanins at high levels in black carrot hairy roots. However, these hairy roots had severe growth problems. We then developed a ß-estradiol inducible system using XVE and a Lex-35S promoter, to initiate expression of the anthocyanin regulators and induced this system in hairy roots of black carrot, tobacco and morning glory. Anthocyanins with various decorations were produced in these hairy roots without any accompanying side-effects on growth. We further produced highly acylated anthocyanins with blue colour in a 5 L liquid culture in a bioreactor of hairy roots from morning glory. We provide here a strategy to produce highly decorated anthocyanins without the need for additional engineering of any of the genes encoding decorating enzymes. This strategy could be transferred to other species, with considerable potential for natural colourant production for the food industries.

Applications of indocyanine greenenhanced fluorescence in the laparoscopic treatment of colonic stricture after necrotizing enterocolitis.

BACKGROUND: The status of anastomotic blood perfusion is associated with the occurrence of anastomotic leakage after intestinal anastomosis. Fluorescence angiography (FA) with indocyanine green (ICG) can objectively assess intestinal blood perfusion. This study aims to investigate whether anastomotic perfusion assessment with ICG influences surgical decision-making during laparoscopic intestinal resection and primary anastomosis for colonic stricture after necrotizing enterocolitis. METHODS: Patients who underwent laparoscopic intestinal resection and primary anastomosis between January 2022 and December 2022 were retrospectively analyzed. Before intestinal anastomosis, the ICG fluorescence technology was used to evaluate the blood perfusion of intestinal tubes on both sides of the anastomosis. After the completion of primary anastomosis, the anastomotic blood perfusion was assessed again. RESULTS: Of the 13 cases, laparoscopy was used to determine the extent of the diseased bowel to be excised, and the normal bowel was preserved for anastomosis. The anastomosis was established under the guidance of ICG fluorescence technology, and FA was performed after anastomosis to confirm good blood flow in the proximal bowel. The anastomotic intestinal tube was changed in one case because FA showed a difference between the normal range of intestinal blood flow and the macroscopic prediction. There was no evidence of ICG allergy, anastomotic leakage, anastomotic stricture, or other complications. The median follow-up was 6 months, and all patients recovered well. CONCLUSIONS: The ICG fluorescence technology is helpful in precisely and efficiently determining the anastomotic intestinal blood flow during stricture resection and in avoiding anastomotic leakage caused by poor anastomotic intestinal blood flow to some extent, with satisfactory short-term efficacy.

Gap-free genome assembly and CYP450 gene family analysis reveal the biosynthesis of anthocyanins in Scutellaria baicalensis.

Scutellaria baicalensis Georgi, a member of the Lamiaceae family, is a widely utilized medicinal plant. The flavones extracted from S. baicalensis contribute to numerous health benefits, including anti-inflammatory, antiviral, and anti-tumor activities. However, the incomplete genome assembly hinders biological studies on S. baicalensis. This study presents the first telomere-to-telomere (T2T) gap-free genome assembly of S. baicalensis through the integration of Pacbio HiFi, Nanopore ultra-long and Hi-C technologies. A total of 384.59 Mb of genome size with a contig N50 of 42.44 Mb was obtained, and all sequences were anchored into nine pseudochromosomes without any gap or mismatch. In addition, we analysed the major cyanidin- and delphinidin-based anthocyanins involved in the determination of blue-purple flower using a widely-targeted metabolome approach. Based on the genome-wide identification of Cytochrome P450 (CYP450) gene family, three genes (SbFBH1, 2, and 5) encoding flavonoid 3'-hydroxylases (F3'Hs) and one gene (SbFBH7) encoding flavonoid 3'5'-hydroxylase (F3'5'H) were found to hydroxylate the B-ring of flavonoids. Our studies enrich the genomic information available for the Lamiaceae family and provide a toolkit for discovering CYP450 genes involved in the flavonoid decoration.

Single-cell analysis technologies for cancer research: from tumor-specific single cell discovery to cancer therapy.

Single-cell sequencing (SCS) technology is changing our understanding of cellular components, functions, and interactions across organisms, because of its inherent advantage of avoiding noise resulting from genotypic and phenotypic heterogeneity across numerous samples. By directly and individually measuring multiple molecular characteristics of thousands to millions of single cells, SCS technology can characterize multiple cell types and uncover the mechanisms of gene regulatory networks, the dynamics of transcription, and the functional state of proteomic profiling. In this context, we conducted systematic research on SCS techniques, including the fundamental concepts, procedural steps, and applications of scDNA, scRNA, scATAC, scCITE, and scSNARE methods, focusing on the unique clinical advantages of SCS, particularly in cancer therapy. We have explored challenging but critical areas such as circulating tumor cells (CTCs), lineage tracing, tumor heterogeneity, drug resistance, and tumor immunotherapy. Despite challenges in managing and analyzing the large amounts of data that result from SCS, this technique is expected to reveal new horizons in cancer research. This review aims to emphasize the key role of SCS in cancer research and promote the application of single-cell technologies to cancer therapy.

Deviation of peak hours for metro stations based on least square support vector machine.

The station-level ridership during the peak hour is one of the key indicators for the design of station size and relevant facilities. However, with the operation of metro system, it cannot be ignored that, in many cities, the station peak and the city peak may not be simultaneously occurred. As the current ridership forecasting methods use the city peak as the point of reference, stations with wide differences of ridership in between would experience disorders due to serious underestimates of passenger demand during the actual peak. Accordingly, this study fully considers the phenomenon that the metro station peak is not identical to the city peak and focuses on the concept of the peak deviation coefficient (PDC), the ratio of the station peak ridership to the city peak ridership. It investigates how metro ridership determinants affects the PDC using the least square support vector machine (LSSVM) model. A land-use function complementarity index is employed as one of the independent variables, which is newly proposed in this study that describes the relationship of the commute land use around an individual station with that along the whole network. This method can help to resolve the ridership amplification indicator for a fine-grained station-level forecasting. The results for Xi'an metro indicate that the LSSVM is an effective method to scrutinize the nonlinear effects of e.g., land use attributes, on the temporal distribution features of the metro ridership. Compared to the ratio of commute land use measured for individual stations, the land-use function complementarity index can better explain and predict the severity of peak deviation phenomenon, controlling other independent variables in the model.

SbMYB3 transcription factor promotes root-specific flavone biosynthesis in Scutellaria baicalensis.

Scutellaria baicalensis Georgi produces abundant root-specific flavones (RSFs), which provide various benefits to human health. We have elucidated the complete biosynthetic pathways of baicalein and wogonin. However, the transcriptional regulation of flavone biosynthesis in S. baicalensis remains unclear. We show that the SbMYB3 transcription factor functions as a transcriptional activator involved in the biosynthesis of RSFs in S. baicalensis. Yeast one-hybrid and transcriptional activation assays showed that SbMYB3 binds to the promoter of flavone synthase II-2 (SbFNSII-2) and enhances its transcription. In S. baicalensis hairy roots, RNAi of SbMYB3 reduced the accumulation of baicalin and wogonoside, and SbMYB3 knockout decreased the biosynthesis of baicalein, baicalin, wogonin, and wogonoside, whereas SbMYB3 overexpression enhanced the contents of baicalein, baicalin, wogonin, and wogonoside. Transcript profiling by qRT-PCR demonstrated that SbMYB3 activates SbFNSII-2 expression directly, thus leading to more abundant accumulation of RSFs. This study provides a potential target for metabolic engineering of RSFs.

Nomogram for the Estimation of Intestinal Necrosis Risk in Incarcerated Inguinal Hernia in Infants under 6 Months.

OBJECTIVE: This article develops a nomogram to estimate intestinal necrosis risk in the incarcerated inguinal hernia (IIH) in infants under 6 months. METHODS: A total of 273 infants who underwent an emergency operation due to IIH were investigated retrospectively. Univariate and multivariate logistic regression were used to analyze the relationship between variables and intestinal necrosis and construct a nomogram of intestinal necrosis. The discrimination and concordance of the model were verified by receiver operating characteristic (ROC) analysis and calibration curve, and the bootstrap method was used for internal validation of the model. The clinical applicability of the model was evaluated using the decision curve and the clinical impact curve. RESULTS: Intestinal necrosis was found in 37 of 273 infants (13.6%) in this study. The vomiting symptoms, platelet count, C-reactive protein, and neutrophil-lymphocyte ratio were independent risk factors for intestinal necrosis in IIH. We then constructed a nomogram with these four factors. ROC analysis showed that the nomogram had a good diagnostic performance, with the area under the curve (AUC), sensitivity, and specificity of 0.918 (95% confidence interval: 0.880-0.956), 97.3%, and 69.9%, respectively. The nomogram was further validated using 2,000-repetition internal bootstrap validation, and the values of AUC, sensitivity, and specificity were 0.899, 95.7%, and 50.5%, respectively. The decision curve and the clinical impact curve indicated that the predictive model has a favorable clinical application. CONCLUSION: The nomogram can be used to predict intestinal necrosis in IIH, and allow us to estimate the severity of IIH more accurately and arrange the treatment process more reasonably.

Targeting Strategies for Aberrant Lipid Metabolism Reprogramming and the Immune Microenvironment in Esophageal Cancer: A Review.

Esophageal cancer is of high importance to occurrence, development, and treatment resistance. As evidenced by recent studies, pathways (e.g., Wnt/ß-catenin, AMPK, and Hippo) are critical to the proliferation, differentiation, and self-renewal of esophageal cancer. In addition, the above pathways play a certain role in regulating esophageal cancer and act as potential therapeutic targets. Over the past few years, the function of lipid metabolism in controlling tumor cells and immune cells has aroused extensive attention. It has been reported that there are intricate interactions between lipid metabolism reprogramming between immune and esophageal cancer cells, whereas molecular mechanisms should be studied in depth. Immune cells have been commonly recognized as a vital player in the esophageal cancer microenvironment, having complex crosstalk with cancer cells. It is increasingly evidenced that the function of immune cells in the tumor microenvironment (TME) is significantly correlated with abnormal lipid metabolism. In this review, the latest findings in lipid metabolism reprogramming in TME are summarized, and the above findings are linked to esophageal cancer progression. Aberrant lipid metabolism and associated signaling pathways are likely to serve as a novel strategy to treat esophageal cancer through lipid metabolism reprogramming.

The Role of Lipid Metabolism in Gastric Cancer.

Gastric cancer has been one of the most common cancers worldwide with extensive metastasis and high mortality. Chemotherapy has been found as a main treatment for metastatic gastric cancer, whereas drug resistance limits the effectiveness of chemotherapy and leads to treatment failure. Chemotherapy resistance in gastric cancer has a complex and multifactorial mechanism, among which lipid metabolism plays a vital role. Increased synthesis of new lipids or uptake of exogenous lipids can facilitate the rapid growth of cancer cells and tumor formation. Lipids form the structural basis of biofilms while serving as signal molecules and energy sources. It is noteworthy that lipid metabolism is capable of inducing drug resistance in gastric cancer cells by reshaping the tumor micro-environment. In this study, new mechanisms of lipid metabolism in gastric cancer and the metabolic pathways correlated with chemotherapy resistance are reviewed. In particular, we discuss the effects of lipid metabolism on autophagy, biomarkers treatment and drug resistance in gastric cancer from the perspective of lipid metabolism. In brief, new insights can be gained into the development of promising therapies through an in-depth investigation of the mechanism of lipid metabolism reprogramming and resensitization to chemotherapy in gastric cancer cells, and scientific treatment can be provided by applying lipid-key enzyme inhibitors as cancer chemical sensitizers in clinical settings.

Analysis of Cases of Neonatal Appendicitis from a Tertiary Care Unit.

OBJECTIVE: To compare the clinical characteristics and prognosis of neonatal appendicitis (NA) alone and neonatal appendicitis with neonatal necrotizing enterocolitis (NEC) to improve the early recognition and diagnosis rate for this type of disease. METHODS: Cases of appendicitis proved by operation and pathology younger than 28 d old in the authors hospital from 1990 to 2021 were retrospectively analyzed. According to whether combine with NEC, the cases were divided into two groups, analyzes the clinical characteristics. RESULTS: A total of 48 patients were enrolled, 15 cases in the NA group and 33 cases in the NEC with NA group. The age of onset, time from onset of symptoms to surgical intervention were both earlier in the NEC with NA group (p < 0.05). The preoperative white blood cells (WBC) and platelets (PLT) in the NA group were higher (p < 0.05). NEC with NA was more likely to be complicated with neonatal pneumonia and sepsis before surgery (p < 0.05). The main clinical symptom of NA was abdominal distension, while the other was bloody stool. The positive rate of ultrasound was high before the operation. The perforation rate of the appendix was very high (NA 100% vs. NEC 57.6%). In the NA group, 100% underwent appendectomy and 78.8% in the NEC with NA group underwent terminal ileostomy and appendectomy. CONCLUSION: The incidence of neonatal appendicitis is low. It is easily misdiagnosed as NEC. The perforation rate is very high, it is recommended to operate as soon as possible, and the prognosis is good.

Characterization of UDP-glycosyltransferase family members reveals how major flavonoid glycoside accumulates in the roots of Scutellaria baicalensis.

BACKGROUND: Flavonoid glycosides extracted from roots of Scutellaria baicalensis exhibit strong pharmaceutical antitumor, antioxidative, anti-inflammatory, and antiviral activities. UDP glycosyltransferase (UGT) family members are responsible for the transfer of a glycosyl moiety from UDP sugars to a wide range of acceptor flavonoids. Baicalin is the major flavonoid glycoside found in S. baicalensis roots, and its aglycone baicalein is synthesized from a specially evolved pathway that has been elucidated. However, it is necessary to carry out a genome-wide study of genes involved in 7-O-glucuronidation, the final biosynthesis step of baicalin, which might elucidate the relationship between the enzymes and the metabolic accumulation patterns in this medicinal plant. RESULTS: We reported the phylogenetic analysis, tissue-specific expression, biochemical characterization and evolutionary analysis of glucosyltransferases (SbUGTs) and glucuronosyltransferases (SbUGATs) genes based on the recently released genome of S. baicalensis. A total of 124 UGTs were identified, and over one third of them were highly expressed in roots. In vitro enzyme assays showed that 6 SbUGTs could use UDP-glucose as a sugar donor and convert baicalein to oroxin A (baicalein 7-O-glucoside), while 4 SbUGATs used only UDP-glucuronic acid as the sugar donor and catalyzed baicalein to baicalin. SbUGAT4 and SbUGT2 are the most highly expressed SbUGAT and SbUGT genes in root tissues, respectively. Kinetic measurements revealed that SbUGAT4 had a lower Km value and higher Vmax/Km ratio to baicalein than those of SbUGT2. Furthermore, tandem duplication events were detected in SbUGTs and SbUGATs. CONCLUSIONS: This study demonstrated that glucosylation and glucuronidation are two major glycosylated decorations in the roots of S. baicalensis. Higher expression level and affinity to substrate of SbUGAT4, and expansion of this gene family contribute high accumulation of baicalin in the root of S. baicalensis.

Rap_GAP Domain of TSC2 Contributes to Tumor Suppression Through mTOR Signaling in Human Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is an aggressive disease with a high degree of tumor heterogeneity. Genetic lesions of mTOR-related genes, including TSC2 and hyperactivation of mTOR signaling, are common in HCC. However, the association of genetic alterations with hepatocarcinogenesis remains unclear. In this study, continuous truncating mutations occurred within or upstream of the TSC2 Rap_GAP domain in clinical HCC samples. To elucidate whether hyperactivation of mTOR signaling in HCC is caused by TSC2 truncating mutations, HCC cell models carrying the TSC2 deletion (CRISPR/Cas9) or the TSC2 truncating mutation (mutagenesis) were established. Our findings showed that either TSC2 deletion or TSC2 mutant could lead to TSC2 loss-of-function and hyperactivation of mTOR signaling. Furthermore, hyperactivation of mTOR signaling was relieved by rapamycin. Immunohistochemistry of clinical samples confirmed frequent TSC2 loss in HCC. Thus, our study revealed that genetic alterations cause TSC2 loss of function and result in the hyperactivation of mTOR, and high frequency of TSC2 truncating mutations around RAP_GAP domain may be one of the reasons for the hyperactivation of mTOR in HCC patients.

Autophagy system as a potential therapeutic target for neurodegenerative diseases.

Autophagy is an evolutionally conserved process by which cytoplasmic contents including protein aggregates and damaged organelles such as mitochondria and lysosomes, are sequestered by double-membrane structure, autophagosomes, and delivered to the lysosomes for degradation. Recently, considerable efforts have been made to reveal the role of autophagy in neurodegenerative diseases like Alzheimer's disease, Parkinson's disease and Huntington's disease. Impairment of autophagy aggravates the accumulation of misfolded protein and damaged organelles in neurons, while sufficient autophagic activity reduces such accumulation in nervous system and ameliorates the pathology. Here we summarize recent progress regarding the role of autophagy in several neurodegenerative diseases and the potential autophagy-associated therapies for them.

Two types of O-methyltransferase are involved in biosynthesis of anticancer methoxylated 4'-deoxyflavones in Scutellaria baicalensis Georgi.

The medicinal plant Scutellaria baicalensis Georgi is rich in specialized 4'-deoxyflavones, which are reported to have many health-promoting properties. We assayed Scutellaria flavones with different methoxyl groups on human cancer cell lines and found that polymethoxylated 4'-deoxyflavones, like skullcapflavone I and tenaxin I have stronger ability to induce apoptosis compared to unmethylated baicalein, showing that methoxylation enhances bioactivity as well as the physical properties of specialized flavones, while having no side-effects on healthy cells. We investigated the formation of methoxylated flavones and found that two O-methyltransferase (OMT) families are active in the roots of S. baicalensis. The Type II OMTs, SbPFOMT2 and SbPFOMT5, decorate one of two adjacent hydroxyl groups on flavones and are responsible for methylation on the C6, 8 and 3'-hydroxyl positions, to form oroxylin A, tenaxin II and chrysoeriol respectively. The Type I OMTs, SbFOMT3, SbFOMT5 and SbFOMT6 account mainly for C7-methoxylation of flavones, but SbFOMT5 can also methylate baicalein on its C5 and C6-hydroxyl positions. The dimethoxylated flavone, skullcapflavone I (found naturally in roots of S. baicalensis) can be produced in yeast by co-expressing SbPFOMT5 plus SbFOMT6 when the appropriately hydroxylated 4'-deoxyflavone substrates are supplied in the medium. Co-expression of SbPFOMT5 plus SbFOMT5 in yeast produced tenaxin I, also found in Scutellaria roots. This work showed that both type I and type II OMT enzymes are involved in biosynthesis of methoxylated flavones in S. baicalensis.