Self-oscillating polymeric refrigerator with high energy efficiency.

Electrocaloric1,2 and electrostrictive3,4 effects concurrently exist in dielectric materials. Combining these two effects could achieve the lightweight, compact localized thermal management that is promised by electrocaloric refrigeration5. Despite a handful of numerical models and schematic presentations6,7, current electrocaloric refrigerators still rely on external accessories to drive the working bodies8-10 and hence result in a low device-level cooling power density and coefficient of performance (COP). Here we report an electrocaloric thin-film device that uses the electro-thermomechanical synergy provided by polymeric ferroelectrics. Under one-time a.c. electric stimulation, the device is thermally and mechanically cycled by the working body itself, resulting in an external-driver-free, self-cycling, soft refrigerator. The prototype offers a directly measured cooling power density of 6.5 W g-1 and a peak COP exceeding 58 under a zero temperature span. Being merely a 30-µm-thick polymer film, the device achieved a COP close to 24 under a 4 K temperature span in an open ambient environment (32% thermodynamic efficiency). Compared with passive cooling, the thin-film refrigerator could immediately induce an additional 17.5 K temperature drop against an electronic chip. The soft, polymeric refrigerator can sense, actuate and pump heat to provide automatic localized thermal management.

Perioperative chemotherapy versus adjuvant chemotherapy treatment for resectable locally advanced gastric cancer: a retrospective cohort study.

BACKGROUND: Neoadjuvant chemotherapy (NAC) is increasingly used in locally advanced gastric cancer (LAGC), but the clinical safety and efficacy are still controversial. This study aims to compare perioperative chemotherapy (PEC) with adjuvant chemotherapy (AC) for resectable LAGC. METHODS: Patients who underwent D2 gastrectomy for resectable LAGC were retrospectively reviewed, and divided into NSA group (NAC plus surgery and AC) and SA group (surgery followed by AC). The baseline characteristics and perioperative data were compared. Survival analysis was based on Kaplan-Meier method. Multivariate analyses for prognostic factors were based on the Cox regression. RESULTS: A total of 450 patients were eligible for this study. 218 patients received NAC plus surgery and AC, while 232 upfront surgery followed by AC. The baseline characteristics were comparable between the two groups. NSA group showed significant superiority in R0 resection rate (P = 0.014), excised tumor size (P = 0.038), and tumor downstage (all P < 0.001). NAC did not affect postoperative complications or AC-related grade 3/4 adverse events. Patients in NSA group achieved significantly longer OS (P = 0.021) and DFS (P = 0.002). The Cox regression model showed that NAC was independently associated with better OS (HR 0.245, P = 0.039) and DFS (HR 0.591, P = 0.031). CONCLUSIONS: Compared with SA, the administration of NSA was considered safe and feasible for achieving higher R0 resection rate without increasing the postoperative complications or AC-related grade 3/4 adverse events, and NAC was independently associated with better OS and DFS for resectable LAGC.

Novel biogenic preparation of gold nanoparticles decorated on sepiolite clay and evaluation of anti-cancer effect on gastric cancer cell and electrochemical sensing of nitrite.

An environmentally friendly strategy was used in this study to synthesize gold nanoparticles decorated on sepiolite clay (GNPs-SC) using Heracleum persicum grass extract. The physicochemical characters of the prepared composite were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). A GNPs-SC modified carbon pate electrode (CPE) was used to study the electrochemical oxidation of nitrite. The proposed nitrite sensor exhibits excellent performance, including a broad linear range (1.0-150 µM), a low limit of detection (0.4 µM), and acceptable reproducibility (RSD = 2.6%). As well, the prepared GNPs-SC was tested for its effectiveness against human gastric adenocarcinoma (AGS) cell line. The MTT assay protocol revealed that the bio-synthesized product displayed significant cytotoxic activity against gastric cancer in human subjects. The findings of this study indicate that GNPs-SC, synthesized using environmentally friendly protocol, exhibit great potential for use in electrochemical sensing and treatment of human cancer.

Comparison of the predictive value of pathological response at primary tumor and lymph node status after neoadjuvant chemotherapy in locally advanced gastric cancer

Background Preoperative chemotherapy has been increasingly used in locally advanced gastric cancer (LAGC). However, the prognostic factors are still insufficient. This study aimed to investigate the prognostic significance of pathological response of the primary tumor to neoadjuvant chemotherapy (NACT) and the lymph node status after NACT. Methods Data from 160 patients with LAGC treated with NACT followed by gastrectomy and met the inclusion criteria between March 2016 and December 2019 were retrospectively reviewed. Pathological evaluation after NACT was based on the grade of pathological response of the primary tumor and the status of lymph node. Survival curves for overall survival (OS) and disease-free survival (DFS) were estimated using the Kaplan–Meier method, and the log-rank test was used to compare survival difference. Univariate and multivariate analyses for prognostic factors were based on the Cox regression. Results Among 160 selected cases, 90 had pathological response (PR), while 70 had no pathological response (nPR) to NACT. Smaller tumor size was presented in PR group, which also had lower level of signet ring cell features, compared to nPR group (all p < 0.05). Based on the status of lymph nodes, nodal status (−) group showed smaller tumor size, lower depth of tumor invasion, better differentiated degree, lower level of signet ring cell features, lower rate of lymphatic and venous invasion and less advanced ypTNM stage (all p < 0.05). Survival was equivalent between PR and nPR group (all p > 0.05), while patients with no lymph node metastasis had better DFS than that with lymph node metastasis (HR 0.301, 95% CI 0.194–0.468, p = 0.002) (AU)

Comparison of the predictive value of pathological response at primary tumor and lymph node status after neoadjuvant chemotherapy in locally advanced gastric cancer.

BACKGROUND: Preoperative chemotherapy has been increasingly used in locally advanced gastric cancer (LAGC). However, the prognostic factors are still insufficient. This study aimed to investigate the prognostic significance of pathological response of the primary tumor to neoadjuvant chemotherapy (NACT) and the lymph node status after NACT. METHODS: Data from 160 patients with LAGC treated with NACT followed by gastrectomy and met the inclusion criteria between March 2016 and December 2019 were retrospectively reviewed. Pathological evaluation after NACT was based on the grade of pathological response of the primary tumor and the status of lymph node. Survival curves for overall survival (OS) and disease-free survival (DFS) were estimated using the Kaplan-Meier method, and the log-rank test was used to compare survival difference. Univariate and multivariate analyses for prognostic factors were based on the Cox regression. RESULTS: Among 160 selected cases, 90 had pathological response (PR), while 70 had no pathological response (nPR) to NACT. Smaller tumor size was presented in PR group, which also had lower level of signet ring cell features, compared to nPR group (all p < 0.05). Based on the status of lymph nodes, nodal status (-) group showed smaller tumor size, lower depth of tumor invasion, better differentiated degree, lower level of signet ring cell features, lower rate of lymphatic and venous invasion and less advanced ypTNM stage (all p < 0.05). Survival was equivalent between PR and nPR group (all p > 0.05), while patients with no lymph node metastasis had better DFS than that with lymph node metastasis (HR 0.301, 95% CI 0.194-0.468, p = 0.002). Multivariable Cox regression analysis identified that lymph node status after NACT was an independent prognostic factor associated with survival (OS: hazard ratio 1.756, 95% CI 1.114-3.278, p = 0.029; DFS: hazard ratio 1.901, 95% CI 1.331-3.093, p = 0.012). CONCLUSION: Lymph node status is a potential independent prognostic factor for LAGC patients treated with NACT and may be more efficient than pathological response in primary tumor.

Association between Plasma FGF21 Levels and Body Composition in Patients with Gastric Cancer.

BACKGROUND: Accumulating evidence has suggested that Fibroblast growth factor 21 (FGF21) plays an important role in metabolic diseases. This study aimed to investigate the relationship between plasma FGF21 levels and body composition parameters in gastric cancer (GC) patients. METHODS: This study was cross-sectional based on a prospective cohort of GC patients in a single center. Computer tomography (CT) and bioelectrical impedance analysis (BIA) were used to estimate skeletal muscle and adipose tissue mass. Blood samples were collected and plasma concentrations of FGF21 were measured by ELISA. Spearman's rank correlation test and logistic regression analysis were performed to assess associations between plasma FGF21 levels and these body composition parameters. RESULTS: A total of 66 GC patients were enrolled in this study. Plasma FGF21 levels were significantly higher in women compared with men. The plasma FGF21 levels were positively correlated with fat mass index (FMI), fat mass percentage (FM%), and subcutaneous adipose tissue index (SATI). Furthermore, after adjustment for confounders, the lower plasma FGF21 levels were remain associated with increased odds for low SATI. CONCLUSIONS: Plasma FGF21 levels were positively associated with FMI, FM%, and SATI in GC patients, suggesting a potential mechanistic link between FGF21 and subcutaneous adipose tissue in GC.

Urolithin A suppresses tumor progression and induces autophagy in gastric cancer via the PI3K/Akt/mTOR pathway.

Urolithin A (UA) is a microbial metabolite of natural polyphenols ellagitannins and ellagic acid with well-established antitumor properties against various malignancies. However, the exact role of UA in gastric cancer (GC) progression remains largely unclear. In the present study, we investigated the effects and potential mechanisms of UA in GC in vitro and in vivo. Our results revealed that UA could suppress GC cell proliferation, inhibit migration and invasion, promote apoptosis, and induce autophagy via the phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin pathway in vitro. The autophagy inhibitors 3-methyladenine and chloroquine augmented the inhibitory effect of UA on proliferation and promoted apoptosis, implying that UA mediated the cytoprotective role of autophagy. Meanwhile, the in vivo experiments showed that UA effectively suppressed tumor growth, enhanced the therapeutic effects, and alleviated chemotherapy toxicity in xenograft models. Overall, these findings offer novel insights into the role of UA in tumor therapy and suggest that UA may possess potential therapeutic applications for GC.

Visceral Adipose Tissue Assessment Enhances the Prognostic Value of GLIM Criteria in Patients with Gastric Cancer Undergoing Radical Gastrectomy after Neoadjuvant Treatment.

BACKGROUND: The Global Leadership Initiative on Malnutrition (GLIM) criteria has been recently published for diagnosing malnutrition in adults. However, the validity of the GLIM criteria has not been well-established in patients with gastric cancer (GC) treated with neoadjuvant treatment (NT) followed by radical gastrectomy. The present study aimed to explore the prognostic value of GLIM-defined malnutrition before NT and after NT in GC patients and to investigate whether additional visceral adipose tissue (VAT) assessment could improve the predictive power of the GLIM criteria for NT-related adverse events (AEs) and long-term survival. METHODS: GC patients who underwent radical surgery after NT from June 2016 to June 2020 were enrolled in this study. The cross-sectional areas of total skeletal muscle (TSM) and VAT were measured using computed tomography (CT) before NT and after NT. GLIM-defined malnutrition was diagnosed using the two-step approach, including nutritional risk screening and diagnostic assessment. Low VAT was also added to the diagnosis of malnutrition in this study. The predictive value of these malnutrition diagnoses for NT-related AEs, and long-term survival was evaluated in GC patients. RESULTS: A total of 182 GC patients were included in this study, of which 66 (36.3%) patients before NT and 55 (30.2%) patients after NT were diagnosed with GLIM-defined malnutrition, respectively. In addition to GLIM-defined malnutrition, 54 (29.7%) patients had additional low VAT before NT, and 39 (21.4%) patients had additional low VAT after NT. GLIM-defined malnutrition alone before NT was not associated with NT-related AEs in GC patients. The addition of low VAT to GLIM-defined malnutrition led to a significant predictive value for NT-related AEs. Furthermore, GLIM-defined malnutrition before NT and after NT were both identified as independent risk factors for overall survival (OS) and disease-free survival (DFS). The combination of low VAT and GLIM-defined malnutrition showed a higher hazard ratio for the prediction of OS and DFS both before NT and after NT. CONCLUSIONS: The addition of VAT assessment using CT improved the predictive value of GLIM-defined malnutrition for NT-related AEs and long-term survival in GC patients treated with NT followed by radical gastrectomy, which further supports the prognostic importance of assessing adipose tissue simultaneously during the routine nutritional assessment in patients with cancer.

Does postoperative chemotherapy improve overall survival of patients with ypT1-2N0 cancer?

BACKGROUND: Perioperative chemotherapy combined with curative gastrectomy has been increasingly represented the standard therapeutic strategy for resectable gastric cancer (GC). However, it is still unclear whether postoperative chemotherapy has a survival benefit for ypT1-2N0 gastric cancer patients who have undergone preoperative chemotherapy followed curative gastrectomy. METHODS: The data of patients who undergone neoadjuvant chemotherapy followed by gastrectomy and had pathological classification of ypT1-2N0 between March 2016 and December 2020 at Peking Union Medical College Hospital were retrospectively reviewed. Chi-square test was adopted to compare the difference between the patients with postoperative chemotherapy (pCHT) and without postoperative chemotherapy (no pCHT). Survival curves for overall survival (OS) were estimated using the Kaplan-Meier method, and the log-rank test was used to compare survival difference. Univariate and multivariate analyses for prognostic factors were based on the Cox regression. RESULTS: A total of 134 patients met the inclusion criteria and 56 (41.8%) of them have undergone postoperative chemotherapy. There were no statistically significant differences in demographic and clinicopathologic characteristics between pCHT group and no pCHT group (all p > 0.05). Postoperative chemotherapy was not associated with a significant improvement in overall survival (OS) (Hazard ratio [HR] 0.815, 95% confidence interval [CI] 0.403-1.650; p = 0.474). Subgroup analyses demonstrated survival was equivalent between pCHT and no CHT group in ypT1N0 patients (HR 0.832, CI 0.222-3.121; p = 0.786) and ypT2N0 patients (HR 1.284, CI 0.564-2.924; p = 0.551). Multivariable analysis identified that clinical T stage independently influenced prognosis (cT3 vs. cT2: HR 2.875, 95% CI 0.998-8.281, p = 0.050; cT4 vs. cT2: HR 7.382, 95% CI 2.569-21.211, p < 0.001). In clinical T3-4 patients, there was an overall survival benefit for postoperative chemotherapy (HR 0.270, 95% CI 0.114-0.634; p = 0.006). No survival benefit of postoperative chemotherapy was identified in clinical T2 patients (HR 0.689, 95% CI 0.200-2.372; p = 0.579). Furthermore, postoperative chemotherapy was proved to be an independently positive prognostic factor for clinical T3-4 patients (HR 0.132, 95% CI 0.051-0.345; p < 0.001). CONCLUSION: Postoperative chemotherapy might offer survival benefit to patients with ypT1-2N0 gastric cancer whose clinical T stage was T3-4 before preoperative chemotherapy.

Crosstalk between tumor-associated macrophages and tumor cells promotes chemoresistance via CXCL5/PI3K/AKT/mTOR pathway in gastric cancer.

BACKGROUND: 5-fluorouracil (5-FU)-based chemotherapy regimen has been widely used for the treatment of gastric cancer, but meanwhile the development of chemotherapeutic resistance remains a major clinical challenge. Tumor microenvironment (TME) frequently correlates with the development of chemoresistance in human cancer. As a major component of TME, the role of tumor-associated macrophages (TAMs) in the chemoresistance of gastric cancer has not been fully elucidated. METHODS: Immunohistochemistry (IHC) was applied to detect the density of TAMs in clinical samples of 103 patients with gastric cancer who had undergone 5-FU-based neoadjuvant chemotherapy. 5-FU-resistant gastric cell lines MKN45-R and HGC27-R were established, macrophages were then separately co-cultured with MKN45-R, HGC27-R cells and their parental cells. The effect of gastric cancer cells on the polarization of macrophages, the biological function of M2-polaried macrophages and the mechanism for promoting 5-FU-resistance were investigated. Then the correlation between the expression of CXC motif chemokine ligand 5 (CXCL5) and the infiltration of hemoglobin scavenger receptor (CD163) positive and mannose receptor (CD206) positive macrophages was analyzed, the prognostic value of CXCL5 expression in clinical samples was further explored. RESULTS: The high infiltration of macrophages marked by CD68 in gastric cancer samples was significantly associated with the resistance of gastric cancer to chemotherapy. Gastric cancer cells could modulate macrophages to M2-like polarization through indirect co-culture, and chemoresistant cells were more efficient in inducing macrophages polarization to M2 phenotype. Co-culturing M2-polarized macrophages in turn enhanced 5-FU-resistance of gastric cancer cells, and it was further verified that CXCL5 derived from M2-polarized macrophages promoted chemoresistance through activing the PI3K/AKT/mTOR pathway. Besides, high level of CXCL5 could recruit monocytes to form more M2-polarized macrophages. Clinically, high expression of CXCL5 in gastric cancer samples was associated with the high infiltration of CD163 positive macrophages and CD206 positive macrophages, and patients with high expression of CXCL5 presented lower overall survival (OS) rates than those with low expression of CXCL5. CONCLUSION: Interaction between TAMs and gastric cancer cells promoted chemoresistance in gastric cancer via CXCL5/PI3K/AKT/mTOR pathway. Thus, targeting TAMs and blocking the cell-cell crosstalk between TAMs and gastric cancer cells may represent prospective therapeutic strategies for patients with gastric cancer.

Long non-coding RNA HNF1A-AS1 induces 5-FU resistance of gastric cancer through miR-30b-5p/EIF5A2 pathway.

BACKGROUND: Gastric cancer (GC) is one of the leading causes of cancer-related deaths worldwide and chemoresistance is a major cause for its poor prognosis. Long non-coding RNAs (lncRNAs) are associated with cancer chemoresistance. The current study sought to explore the mechanism of lncRNA HNF1A antisense RNA 1 (HNF1A-AS1) in mediating 5-fluorouracil (5-FU) resistance of GC. METHODS: qRT-PCR was performed to detect the expression level of HNF1A-AS1 in GC tissues and cells. Abnormal expression of HNF1A-AS1 in GC cells was induced by lentivirus infection. Protein levels of EIF5A2, E-Cadherin, Vimentin and N-Cadherin were detected using western blot. Competitive endogenous RNA (ceRNA) mechanisms were explored through luciferase assays and RNA immunoprecipitation (RIP) assays. Functional experiments of chemoresistance were performed by CCK-8 assays, colony formation assays and flow cytometry with the treatment of 5-FU. Mouse tumor xenograft assays were performed to verify the findings in vivo. RESULTS: The findings showed HNF1A-AS1 was significantly upregulated in GC tissues especially in chemoresistance group. Findings from in vitro and in vivo experiments showed HNF1A-AS1 increased cell viability and proliferation, repressed apoptosis and promoted xenograft tumors growth in the presence of 5-FU. Mechanistic studies revealed HNF1A-AS1 promoted chemoresistance by facilitating epithelial mesenchymal transition (EMT) process through upregulating EIF5A2 expression and HNF1A-AS1 acted as a sponge of miR-30b-5p. CONCLUSIONS: The findings from the current study showed HNF1A-AS1 promoted 5-FU resistance by acting as a ceRNA of miR-30b-5p and promoting EIF5A2-induced EMT process in GC. This indicates that HNF1A-AS1 is a potential therapeutic target for alleviating GC chemoresistance.

Impact of body composition on clinical outcomes in people with gastric cancer undergoing radical gastrectomy after neoadjuvant treatment.

OBJECTIVES: The influence of body composition on clinical outcomes in individuals with gastric cancer (GC) undergoing radical gastrectomy after neoadjuvant treatment (NT) remains unclear. The purpose of this retrospective study was to investigate the association between body composition before NT or after NT and clinical outcomes in individuals with GC receiving multimodal treatments. METHODS: This retrospective study included individuals with GC who received NT followed by radical gastrectomy between January 2016 and December 2018. Skeletal muscle, visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT) were measured by cross-sectional areas at the level of third lumbar vertebra based on single-slice computed tomography scan prior to NT and prior to the surgical operation. Sarcopenia, high VAT, and high SAT were defined using cutoff points of skeletal muscle index, visceral fat area, and subcutaneous fat area. Univariate and multivariate analyses were performed to evaluate risk factors of NT-related adverse events, postoperative complications and predictors of long-term survival. RESULTS: A total of 110 individuals with GC were enrolled in this study. Sarcopenia was present in 62.7% of them before NT and in 56.4% after NT. Sarcopenia before NT was associated with more NT-related adverse events (odds ratio, 2.901; 95% confidence interval [CI], 1.205-6.983; P = 0.018). High VAT after NT (≥106 cm2) was associated with an increasing incidence of postoperative complications (odds ratio, 4.261; 95% CI, 1.332-13.632; P = 0.015). No body-composition parameter was relevant to tumor pathologic response to NT. As for long-term survival, poor overall survival was associated with both low VAT before NT (<120 cm2; hazard ratio [HR], 2.542; 95% CI, 1.111-5.817; P = 0.027) and low SAT after NT (<99.5 cm2; HR, 2.743; 95% CI, 1.248-6.027; P = 0.012). Similarly, shorter disease-free survival was associated with low VAT before NT (<120 cm2; HR, 2.502; 95% CI, 1.222-5.124; P = 0.012) and low VAT after NT (<106 cm2; HR, 2.505; 95% CI, 1.172-5.358; P = 0.018). CONCLUSIONS: Body composition measured by computed tomography could predict NT-related adverse events, postoperative complications, and long-term survival in multimodal treatments for GC. More meaningfully, adipose-tissue status has significant prognostic value for individuals with advanced GC.

Marked loss of adipose tissue during neoadjuvant therapy as a predictor for poor prognosis in patients with gastric cancer: A retrospective cohort study.

BACKGROUND: The influence of body composition changes during neoadjuvant treatment (NT) on long-term survival in patients with gastric cancer (GC) undergoing radical gastrectomy remains unclear. The present study aimed to explore the association between changes in body composition during NT and survival in patients with GC. METHODS: GC patients treated with NT and radical gastrectomy between 2015 and 2018 were included in this retrospective study. Skeletal muscle mass, visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were measured by computer tomography before and after NT. Body composition changes during NT were compared with Kaplan-Meier curves. Univariate and multivariate regression analyses were applied to determine the predictors of overall survival (OS) and disease-free survival (DFS). RESULTS: In total, 157 GC patients were studied. A marked loss of adipose tissue was associated with poor nutritional status. The median follow-up time for all patients was 25 months. Patients with marked VAT loss (≥ 35.7%) during NT had significantly shorter OS (p = 0.028) and DFS (p = 0.03). Similarly, poorer OS (p = 0.033) and DFS (p = 0.003) were observed in patients with marked SAT loss (≥ 30.1%) during NT. Changes in skeletal muscle mass and body weight during NT were not associated with survival. Marked VAT loss accompanied by marked SAT loss was an independent predictor of OS (hazards ratio = 2.447; p = 0.045) and DFS (hazards ratio = 2.674; p = 0.018). CONCLUSIONS: Patients with locally advanced GC have a worse survival when they experienced marked loss of adipose tissue during NT.

CT Radiomics for Distinction of Human Epidermal Growth Factor Receptor 2 Negative Gastric Cancer.

RATIONALE AND OBJECTIVES: The purpose of this study was to investigate the role of computed tomography (CT) radiomics for the prediction of the human epidermal growth factor 2 (HER2) status in patients with gastric cancer. METHODS: One hundred and thirty two consecutive patients with advanced gastric cancer undergoing radical gastrectomy were retrospectively reviewed. All patients received preoperative contrast CT examination, and immunohistochemistry results of their HER2 status were available. All the subjects were randomly divided into a training cohort (n = 90) and a test cohort (n = 42). Arterial phase (AP) and portal phase (PP) contrast CT images were retrieved for tumor segmentation and feature extraction. Receiver operating characteristics (ROC) curves and area under the curve (AUC) were used to evaluate the performance of the radiomics classifiers. RESULTS: Among the 132 patients, a total of 99 patients were HER2 negative, and the remaining 33 patients were border line or positive. The AP radiomics model could distinguish HER2-negative cases with an AUC of 0.756 (95% confidence interval [CI]: 0.656-0.840) in the training cohort, which was confirmed in the test cohort with AUC of 0.830 (95% CI: 0.678-0.930). The PP radiomics model showed AUCs of 0.715 (95% CI: 0.612-0.804) and 0.718 (95% CI: 0.554-0.849) in the training and test cohort for distinction of negative HER2 cases, respectively. CONCLUSION: Radiomics models based on standard-of-care CT images hold promise for distinguishing HER2-negative gastric cancer.

The role of MRI in the diagnosis and treatment of gastric cancer.

Gastric cancer is the fifth most common malignancies and the third leading cause of cancer-related death worldwide, with more than 40% of new cases occurring in China. With the advancement of treatment methods, the application of adjuvant therapy and targeted drugs, the prognosis of patients with gastric cancer has been significantly improved. In recent years, more and more studies have reported that magnetic resonance imaging (MRI) showed great value in the clinical application among patients with gastric cancer, including preoperative staging, treatment response evaluation, predicting prognosis and histopathological features, treatment guidance, and molecular imaging. The remarkable research progress of MRI in gastric cancer will provide new evaluation and treatment approaches for clinical diagnosis and treatment. This article aims to review the current status of the application and research progress of MRI in patients with gastric cancer.

Histone methylation regulates Hif-1 signaling cascade in activation of hepatic stellate cells.

Liver fibrosis is characterized by deposition of excessive extracellular matrix (ECM). The major source of ECM is activated hepatic stellate cells (HSCs). Previously, we reported that hypoxia-inducible factor-1 (Hif-1) regulates activation of HSCs through autophagy. In current work, human HSC cell line LX-2 was used as cell model. It was determined that trimethylation of H3 histone on lysine 4 (H3K4me3) occurred in the Hif-1 transcriptional complex. Inhibition of modifications of histone methylation suppressed Hif-1 nuclear transport, autophagosome formation, and activation of LX-2 cells. These data suggest that histone methylation modification plays an important role in the Hif-1 signaling cascade regulating HSC activation.

Expression and characterization of a novel mesophilic protease from metagenomic library derived from Antarctic coastal sediment.

A metagenomic cosmid library was constructed, in which the insert DNA was derived from the coastal sediment near Antarctic China Zhongshan Station. One clone (ACPRO001) expressing protease activity was isolated from the library using milk agar plates. Sequencing of the clone revealed a novel protease gene. The amino acid sequence comparison and phylogenetic analysis indicated that it could be classified as a subtilisin-like serine protease, though the highly conserved residue Asp was replaced by Ala. The ACPRO001 protease gene was expressed in pET-His and purified for characterization. The optimal temperature and pH for the activity of the ACPRO001 protease were 60°C and pH 9.0, respectively. The enzyme retained about 73% of residual activity after 2 h incubation at 50°C in the presence of Ca(2+). The presence of Ca(2+) increased the thermostability of ACPRO001 protease obviously. The enzymatic activity was inhibited by 1 mM phenylmethyl sulfonylfluoride (PMSF) and hydrochloride 4-(2-aminoethyl)-benzenesulfonyl fluoride (AEBSF), indicating that it was a serine protease.