Experimental and Meshless Numerical Simulations on the Crack Propagation of Semi-Circular Bending Specimens Containing X-Shaped Fissures Under Three-Point Bending.

Cracks in rock and concrete have a great adverse effect on the stability of engineering structures; however, there are few studies on X-shaped fissures which widely exist in rock and concrete structures. Based on this background, three-point bending fracture tests of SCB specimens containing X-shaped fissures are carried out. The momentum equations in the SPH method are improved, and the crack propagations of SCB specimens under three-point bending are simulated. The results show that cracks grow simply along the vertical direction in the sample with no X-shaped fissures, and the existence of an X-shaped fissure changes the crack growth path and final failure modes of the SCB samples. The crack propagation simulation results are consistent with the experimental results, which verifies the rationality of the improved SPH method. The load-displacement curves mainly present three typical stages: the initial compaction stage, linear elastic deformation stage, and failure stage. The peak load decreases first then increases with an increase in eccentricity. With an increase in X-shaped fissure length and decrease in X-shaped fissure angle, the peak load decreases. The damage counts remain at 0 at the initial loading stage, corresponding to the initial compaction stage and the linear elastic deformation stage, and increase sharply at the later loading stage, corresponding to the failure stage, which is consistent with the experimental results. The influence mechanisms of X-shaped fissures on the crack propagation paths are discussed; the existence of different X-shaped fissure morphologies aggravate the tensile stress concentration at specific positions, leading to different crack propagation modes in the experiments. The research results can provide a certain reference for understanding the failure mechanisms of engineering structures containing X-shaped fissures and promote the applications of the SPH method into the simulations of cross-fissure crack propagations.

m1A regulator-mediated methylation modification patterns correlated with autophagy to predict the prognosis of hepatocellular carcinoma.

BACKGROUND: N1-methyladenosine (m1A), among the most common internal modifications on RNAs, has a crucial role to play in cancer development. The purpose of this study were systematically investigate the modification characteristics of m1A in hepatocellular carcinoma (HCC) to unveil its potential as an anticancer target and to develop a model related to m1A modification characteristics with biological functions. This model could predict the prognosis for patients with HCC. METHODS: An integrated analysis of the TCGA-LIHC database was performed to explore the gene signatures and clinical relevance of 10 m1A regulators. Furthermore, the biological pathways regulated by m1A modification patterns were investigated. The risk model was established using the genes that showed differential expression (DEGs) between various m1A modification patterns and autophagy clusters. These in vitro experiments were subsequently designed to validate the role of m1A in HCC cell growth and autophagy. Immunohistochemistry was employed to assess m1A levels and the expression of DEGs from the risk model in HCC tissues and paracancer tissues using tissue microarray. RESULTS: The risk model, constructed from five DEGs (CDK5R2, TRIM36, DCAF8L, CYP26B, and PAGE1), exhibited significant prognostic value in predicting survival rates among individuals with HCC. Moreover, HCC tissues showed decreased levels of m1A compared to paracancer tissues. Furthermore, the low m1A level group indicated a poorer clinical outcome for patients with HCC. Additionally, m1A modification may positively influence autophagy regulation, thereby inhibiting HCC cells proliferation under nutrient deficiency conditions. CONCLUSIONS: The risk model, comprising m1A regulators correlated with autophagy and constructed from five DEGs, could be instrumental in predicting HCC prognosis. The reduced level of m1A may represent a potential target for anti-HCC strategies.

NAP1L1 regulates BIRC2 ubiquitination modification via E3 ubiquitin ligase UBR4 and hence determines hepatocellular carcinoma progression.

We have previously shown that nucleosome assembly protein 1-like 1 (NAP1L1) plays an important role in the abnormal proliferation of hepatocellular carcinoma (HCC) cells. However, the effects of NAP1L1 on the malignant behaviour of HCC cells, including cell migration, invasion and apoptosis, remain unclear. Baculoviral IAP repeat-containing 2 (BIRC2) plays a key role in initiating the abnormal proliferation, apoptotic escape and multidrug resistance of HCC cells; however, the mechanisms through which its stability is regulated in HCC remain elusive. Here, we found that knockdown of NAP1L1 inhibited the proliferation of HCC cells and activated apoptotic pathways but did not remarkably affect the migratory and invasive abilities of HCC cells. In addition, knockdown of NAP1L1 did not alter the expression of BIRC2 at the transcriptional level but substantially reduced its expression at the translational level, suggesting that NAP1L1 is involved in the post-translational modification (such as ubiquitination) of BIRC2. Furthermore, BIRC2 was highly expressed in human HCC tissues and promoted the proliferation and apoptotic escape of HCC cells. Co-immunoprecipitation (Co-IP) assay and mass spectrometry revealed that NAP1L1 and BIRC2 did not bind to each other; however, ubiquitin protein ligase E3 component n-recognin 4 (UBR4) was identified as an intermediate molecule associating NAP1L1 with BIRC2. Knockdown of NAP1L1 promoted the ubiquitin-mediated degradation of BIRC2 through the ubiquitin-protein junction of UBR4, which in turn inhibited the proliferation and apoptotic escape of HCC cells and exerted anti-tumour effects. In conclusion, this study reveals a novel mechanism through which NAP1L1 regulates the ubiquitination of BIRC2 through UBR4, thereby determining the progression of HCC. Based on this mechanism, suppression of NAP1L1 may inhibit tumour progression in patients with HCC with high protein expression of NAP1L1 or BIRC2.

An integrative pan-cancer analysis of the molecular characteristics of dietary restriction in tumour microenvironment.

BACKGROUND: Dietary restriction (DR), a general term for dieting, has been demonstrated as an effective intervention in reducing the occurrence of cancers. Molecular activities associated with DR are crucial in mediating its anti-cancer effects, yet a comprehensive exploration of the landscape of these activities at the pan-cancer level is still lacking. METHODS: We proposed a computational approach for quantifying DR-related molecular activities and delineating the landscape of these activities across 33 cancer types and 30 normal tissues within 27,320 samples. We thoroughly examined the associations between DR-related molecular activities and various factors, including the tumour microenvironment, immunological phenotypes, genomic features, and clinical prognosis. Meanwhile, we identified two DR genes that show potential as prognostic predictors in hepatocellular carcinoma and verified them by immunohistochemical assays in 90 patients. FINDINGS: We found that DR-related molecular activities showed a close association with tumour immunity and hold potential for predicting immunotherapy responses in various cancers. Importantly, a higher level of DR-related molecular activities is associated with improved overall survival and cancer-specific survival. FZD1 and G6PD are two DR genes that serve as biomarkers for predicting the prognosis of patients with hepatocellular carcinoma. INTERPRETATION: This study presents a robust link between DR-related molecular activities and tumour immunity across multiple cancer types. Our research could open the path for further investigation of DR-related molecular processes in cancer treatment. FUNDING: National Natural Science Foundation of China (Grant No. 82000628) and the Guangdong-Hong Kong-Macao University Joint Laboratory of Interventional Medicine Foundation of Guangdong Province (Grant No. 2023LSYS001).

Metagenomic analysis reveals gut plasmids as diagnosis markers for colorectal cancer.

Background: Colorectal cancer (CRC) is linked to distinct gut microbiome patterns. The efficacy of gut bacteria as diagnostic biomarkers for CRC has been confirmed. Despite the potential to influence microbiome physiology and evolution, the set of plasmids in the gut microbiome remains understudied. Methods: We investigated the essential features of gut plasmid using metagenomic data of 1,242 samples from eight distinct geographic cohorts. We identified 198 plasmid-related sequences that differed in abundance between CRC patients and controls and screened 21 markers for the CRC diagnosis model. We utilize these plasmid markers combined with bacteria to construct a random forest classifier model to diagnose CRC. Results: The plasmid markers were able to distinguish between the CRC patients and controls [mean area under the receiver operating characteristic curve (AUC = 0.70)] and maintained accuracy in two independent cohorts. In comparison to the bacteria-only model, the performance of the composite panel created by combining plasmid and bacteria features was significantly improved in all training cohorts (mean AUCcomposite = 0.804 and mean AUCbacteria = 0.787) and maintained high accuracy in all independent cohorts (mean AUCcomposite = 0.839 and mean AUCbacteria = 0.821). In comparison to controls, we found that the bacteria-plasmid correlation strength was weaker in CRC patients. Additionally, the KEGG orthology (KO) genes in plasmids that are independent of bacteria or plasmids significantly correlated with CRC. Conclusion: We identified plasmid features associated with CRC and showed how plasmid and bacterial markers could be combined to further enhance CRC diagnosis accuracy.

Exploring the Characteristics of Functional Dysphonia by Multimodal Methods.

OBJECTIVES: To explore the characteristics of functional dysphonia (FD) using multimodal methods. METHODS: A total of 47 FD patients and a group of 22 normal controls were enrolled. Subjective auditory-perceptual assessment of the voice, Voice Handicap Index (VHI) 30, acoustic analysis, psychological scales assessment, surface electromyography (sEMG), nasal airflow and thoracoabdominal studies were performed. RESULTS: FD was mostly triggered by mood changes. Patient self-evaluation was more serious than auditory-perceptual evaluation and objective acoustic analysis. There was no obvious organic disorder observed under laryngoscope in patients with FD, but there were cases of glottic insufficiency and supraglottic compensation. With regards to sEMG, nasal airflow, chest, and abdomen examination results: (1) sEMG in the normal control group was symmetrical and stable on both sides during rest and phonation, and nasal airflow as well as the chest and abdomen were symmetrical and regular; (2) sEMG in the FD group showed increased recruitment of the sternocleidomastoid muscles, the infra- and suprahyoid muscles, and the cricothyroid muscle, accompanied by prephonation recruitment and postphonation persistence, mainly involving the infra- and suprahyoid muscles; (3) In the FD group, there was shortened inspiratory time, increased chest breathing amplitude, and reduced abdominal breathing, with predominantly chest breathing, and a "breath-holding" phenomenon was observed in some patients, with a significant increase in the number of breaths during the short text task. CONCLUSIONS: FD occurs mainly in middle-aged women, and there are many triggers. The Hamilton Anxiety/Depression Rating Scale scores were higher, and subjective symptoms were more serious than objective evaluation. No obvious organic changes were seen under laryngoscope, and features such as supraglottic compensation and glottic insufficiency were observed; muscle tension was significantly higher than that of the normal control group, and prephonation recruitment and postphonatory persistence were seen in some patients; the breathing pattern was mainly chest breathing, and the times of breaths during the short text task significantly increased. With identification of the characteristics of FD, the therapy could be focused them.

The RAISE Trial: A Novel Device and First-in-Man Trial.

BACKGROUND: Currently, standard medical therapies have limited effects on heart failure with preserved ejection fraction (HFpEF), which impacts on the life quality and survival of patients. This study aimed to evaluate the safety and efficacy of the percutaneous radiofrequency ablation-based interatrial shunting for HFpEF with a novel atrial septostomy device. METHODS: A preclinical study in 11 normal domestic pigs and the first-in-man study in 10 patients with HFpEF were performed. The major safety events and interatrial shunt performance were evaluated at baseline, 1 month, 3 months, and 6 months post-procedure in both animals and human patients. The clinical functional status was also assessed in the first-in-man study. RESULTS: Percutaneous radiofrequency ablation-based interatrial shunting therapy was performed successfully both in animals and patients. In the animal study, a left-to-right interatrial shunt was created with a mean defect size of 5.5±2.2 mm without procedure-related safety events. Seven pigs showed the continuous shunting with a mean defect size of 4.1±1.5 mm at 6 months. In the first-in-man study, a median interatrial defect diameter of 5.0 (4.0-6.0) mm was measured immediately. No major safety events including death and thromboembolism were observed. The continuous shunting with the defect size of 4.0 (3.0-4.0) mm could still be observed in 7 patients at 6 months. The clinical status was significantly improved with NT-proBNP (N-terminal pro-B-type natriuretic peptide) reduced by 2149 pg/mL ([95% CI, 204-3301] P=0.028), with 6-minute walk distance increased by 88 m ([95% CI, 50-249] P=0.008) and with New York Heart Association class improved in 8 patients at 6 months. CONCLUSIONS: The present results showed that percutaneous radiofrequency ablation-based interatrial shunting was a safe and potentially effective therapy for HFpEF, providing a nonpharmacological and nonimplanted option for HFpEF management. REGISTRATION: URL: https://www.chictr.org.cn; Unique identifier: ChiCTR1900027664.

Unified Deep Learning Model for Multitask Reaction Predictions with Explanation.

There is significant interest and importance to develop robust machine learning models to assist organic chemistry synthesis. Typically, task-specific machine learning models for distinct reaction prediction tasks have been developed. In this work, we develop a unified deep learning model, T5Chem, for a variety of chemical reaction predictions tasks by adapting the "Text-to-Text Transfer Transformer" (T5) framework in natural language processing (NLP). On the basis of self-supervised pretraining with PubChem molecules, the T5Chem model can achieve state-of-the-art performances for four distinct types of task-specific reaction prediction tasks using four different open-source data sets, including reaction type classification on USPTO_TPL, forward reaction prediction on USPTO_MIT, single-step retrosynthesis on USPTO_50k, and reaction yield prediction on high-throughput C-N coupling reactions. Meanwhile, we introduced a new unified multitask reaction prediction data set USPTO_500_MT, which can be used to train and test five different types of reaction tasks, including the above four as well as a new reagent suggestion task. Our results showed that models trained with multiple tasks are more robust and can benefit from mutual learning on related tasks. Furthermore, we demonstrated the use of SHAP (SHapley Additive exPlanations) to explain T5Chem predictions at the functional group level, which provides a way to demystify sequence-based deep learning models in chemistry. T5Chem is accessible through https://yzhang.hpc.nyu.edu/T5Chem.

Gap between risk factors and prevention strategies? A nationwide survey of fall prevention among medical and surgical patients.

AIMS: This study aimed to determine the extent to which nurses report assessing evidence-based falls risk factors and implementing targeted prevention for medical and surgical patients in China. DESIGN: This study was a national online survey. METHODS: The respondents were registered nurses working in medical and surgical units in 662 Chinese hospitals. The data concerning the falls risk factor assessments and targeted interventions implemented by nurses were collected online by the Nursing Management Committee of the Chinese Nursing Association in China in 2019. RESULTS: In total, 68 527 valid questionnaires were returned (95.0%). In medical and surgical units, nurses were most likely to report assessing balance, mobility and strength (81.6%) and orthostatic hypotension (76.4%) in falls patients and least likely to report assessing continence (61.3%) and feet and footwear (55.8%). Ensuring the use of appropriate footwear (79.3%) and managing syncope, dizziness and vertigo (73.8%) were the most common multiple interventions, while managing postural hypotension (48.8%) and cognitive impairment (48.4%) was the least common. Nine falls risk factors with clearly matched multifactorial interventions were identified in medical and surgical units (68.2%-97.1%). CONCLUSIONS: The implementation of multifactorial interventions in medical and surgical wards is inconsistent as reported by nurses in medical and surgical wards. Throughout China, nurses are generally concerned about falls risk factors and prevention for their patients; however, limited attention has been focused on continence, feet and footwear assessment and the management of cognitive impairment. Evidence-based falls prevention should be further tailored to the specific risk factors of each patient. IMPACT: Best practice guidelines for falls prevention in hospitals have been developed and published, and it is important for nurses to use these guidelines to guide practice. Our findings identify that in routine care, healthcare providers and hospitals can prevent falls.

Aortic valve repair for the treatment of rheumatic aortic valve disease: a systematic review and meta-analysis.

Valvuloplasty for rheumatic aortic valve disease remains controversial. We conducted this study to explore whether aortic valvuloplasty is appropriate for the rheumatic population. A comprehensive search was conducted, and 7 eligible retrospective studies were identified from PubMed, Embase, Medline and Cochrane (up to April 7, 2020) according to the inclusion and exclusion criteria. The data for hospital mortality, 5-year survival, 5-year reoperation, aortic insufficiency grade (AIG) and aortic valve gradient (AVG) were extracted by 2 independent reviewers and were analysed to evaluate the safety and availability of aortic valvuloplasty for rheumatic patients. The heterogeneity of the results was estimated using the Q test and I2 statistics. The fixed pooling model was used when I2 ≤ 50%; otherwise, the random pooling model was selected. 7 articles with 418 patients were included. The pooled hospital mortality, 5-year survival and 5-year reoperation rates were 3.2%, 94.5% and 9.9%, respectively. The heterogeneities of the weighted mean differences (WMD) values of the AIG and AVG between preoperation and postoperation were extremely high (I2 = 81.5%, p < 0.001 in AIG, I2 = 97.6%, p = 0.003 in AVG). Subgroup analysis suggested that the AIG and AVG were improved by 3.03 grades (I2 = 0%, p < 0.001) and 3.16 mmHg (I2 = 0%, p < 0.001) in the European group, respectively. In the Asian group, the AIG and AVG were improved by 2.57 grades (I2 = 0%, p < 0.001) and 34.39 mmHg (I2 = 0%, p < 0.001), respectively. Compared with the values at discharge, the AIG was increased by 0.15 grades (I2 = 0%, p = 0.031) and the AVG was still decreased by 2.07 mmHg (I2 = 0%, p = 0.031) at the time of follow up. Valvuloplasty is safe and effective to treat rheumatic aortic insufficiency and stenosis, and the duration of maintenance required to improve stenosis was longer than that of insufficiency.

Dataset Construction to Explore Chemical Space with 3D Geometry and Deep Learning.

A dataset is the basis of deep learning model development, and the success of deep learning models heavily relies on the quality and size of the dataset. In this work, we present a new data preparation protocol and build a large fragment-based dataset Frag20, which consists of optimized 3D geometries and calculated molecular properties from Merck molecular force field (MMFF) and DFT at the B3LYP/6-31G* level of theory for more than half a million molecules composed of H, B, C, O, N, F, P, S, Cl, and Br with no larger than 20 heavy atoms. Based on the new dataset, we develop robust molecular energy prediction models using a simplified PhysNet architecture for both DFT-optimized and MMFF-optimized geometries, which achieve better than or close to chemical accuracy (1 kcal/mol) on multiple test sets, including CSD20 and Plati20 based on experimental crystal structures.

Comparative Study of Metabolite Changes After Antihypertensive Therapy With Calcium Channel Blockers or Angiotensin Type 1 Receptor Blockers.

ABSTRACT: The high prevalence of hypertension contributes to an increased global burden of cardiovascular diseases. Calcium channel blockers (CCBs) and angiotensin type 1 receptor blockers (ARBs) are the most widely used antihypertensive drugs, and the effects of these drugs on serum metabolites remain unknown. Untargeted metabolomics has been proved to be a powerful approach for the detection of biomarkers and new compounds. In this study, we aimed to determine the changes in metabolites after single-drug therapy with a CCB or ARB in patients newly diagnosed with mild to moderate primary hypertension. We enrolled 33 patients and used an untargeted metabolomics approach to measure 625 metabolites associated with the response to a 4-week treatment of antihypertensive drugs. After screening based on P < 0.05, fold change > 1.2 or fold change < 0.83, and variable importance in projection > 1, 63 differential metabolites were collected. Four metabolic pathways-cysteine and methionine metabolism, phenylalanine metabolism, taurine and hypotaurine metabolism, and tyrosine metabolism-were identified in participants treated with ARBs. Only taurine and hypotaurine metabolism were identified in participants treated with CCBs. Furthermore, homocitrulline and glucosamine-6-phosphate were relevant to whether the blood pressure reduction achieved the target blood pressure (P < 0.05). Our study provides some evidence that changes in certain metabolites may be a potential marker for the dynamic monitoring of the protective effects and side effects of antihypertensive drugs.

Tocilizumab for treating COVID-19: a systemic review and meta-analysis of retrospective studies.

OBJECTIVES: COVID-19 has become a global epidemic, and effective therapies have not been discovered up to now. We conducted this study to explore the effectiveness and safety of tocilizumab recently used for treating COVID-19. METHOD: A comprehensive search was conducted (up to September 27, 2020), and 19 eligible records were identified according to the inclusion and exclusion criteria. The data of the studies were extracted by 2 independent reviewers and were analyzed to evaluate the safety and availability of tocilizumab for treating COVID-19. RESULTS: Thirteen retrospective case-control studies (n = 2285 patients) and 6 retrospective single-armed studies (n = 208) were retrieved in this study. In the comparison of tocilizumab treatment group (TCZ) and standard treatment group (ST), significant associations with a lower risk of admission to ICU, use of ventilation, and mortality (OR, 95% CI: 0.53, 0.26~1.09; 0.66, 0.46~0.94; 0.44, 0.36~0.55) were found in the tocilizumab treatment group. What is more, patients treated with tocilizumab had better clinical improvement compared with the patients treated with ST (OR, 1.24; 95% CI, 0.96~1.62). After taking tocilizumab, the patients had lower C-reactive protein (CRP), white blood cell count (WBC), aspartate aminotransferase (AST) (WMD, 95% CI: - 99.66, - 156.24~- 43.09; - 0.95, - 1.8~- 0.11; - 12.58, - 18.88~-6.29) but higher troponin (WMD, 7.61; 95% CI, 3.06~12.15) than before. In addition, tocilizumab did not have significant influence on patients' neutrophil count (Neut), lymphocyte count (Lymp), platelet count (Plt), alanine aminotransferase (ALT), and creatine (WMD, 95% CI: - 0.29, - 2.91~2.33; 0.42, - 0.23~1.07; 5.2, - 2.85~13.25; 22.49, - 2.73~47.7; - 44.78, - 93.37~3.81). CONCLUSION: Tocilizumab may have potential effectiveness to treat COVID-19 according to the results of this study. However, more large-scale studies are needed for more accurate conclusions.

Long Non-Coding RNA BACE1-AS Modulates Isoflurane-Induced Neurotoxicity to Alzheimer's Disease Through Sponging miR-214-3p.

Isoflurane, an anesthetic, can aggravate the progression of Alzheimer's disease (AD). Long non-coding RNA ß-secretase 1 (BACE1)-antisense transcript (BACE1-AS) and miR-214-3p are related to AD progression. Nevertheless, it is unclear whether BACE1-AS is involved in the development of isoflurane-mediated AD via miR-214-3p. Amyloid beta peptide (Aß) was employed to construct the AD cell model. The expression of BACE1-AS and miR-214-3p in the plasma of AD patients and SK-N-SH and SK-N-AS cells treated with Aß and isoflurane was assessed through quantitative reverse transcription polymerase chain reaction (qRT-PCR). The proliferation and apoptosis of Aß-treated SK-N-SH and SK-N-AS cells were determined via 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) or flow cytometry assays, respectively. Protein levels of B cell lymphoma 2 (Bcl-2), Bcl-2-associated X (Bax), CyclinD1, microtubule-associated protein A1/1B-light chain3 (LC3 I/LC3 II), p62 and Beclin1 were detected via western blot analysis. The relationship between BACE1-AS and miR-214-3p was verified by dual-luciferase reporter assay. We found that BACE1-AS was upregulated and miR-214-3p was downregulated in the plasma of AD patients and SK-N-SH and SK-N-AS cells treated with Aß and isoflurane. Both BACE1-AS depletion and miR-214-3p augmentation restored the suppression of proliferation and the facilitation of apoptosis and autophagy of Aß-treated SK-N-SH and SK-N-AS cells induced by isoflurane. Importantly, BACE1-AS acted as a sponge for miR-214-3p. Additionally, miR-214-3p silencing reversed the influence of BACE1-AS knockdown on isoflurane-mediated proliferation, apoptosis and autophagy in Aß-induced SK-N-SH and SK-N-AS cells. In conclusion, BACE1-AS aggravated isoflurane-induced neurotoxicity to AD via sponging miR-214-3p.

Prolactin may serve as a regulator to promote vocal fold wound healing.

Reduced prolactin (PRL) has been shown to delay wound healing with a limited understanding of the underlying mechanisms. Here, we aim to explore the role of PRL in the repair of vocal fold (VF) injury. A microarray was used to detect the expressed levels of PRL in rat VF tissue at 1, 4, and 8 weeks after VF injury compared with normal uninjured rats. Then, a systematic bioinformatics analysis has been conducted to explore the literature-based biology network and signaling pathways involved in the repair of VF injury. The expression of PRL was significantly decreased in all VF injury groups (week 1, 4, and 8) compared with the control group (F stats = 280.34; P=4.88e-14), with no significant difference among the three VF injury groups (F stats = 1.97; P=0.18). Wounding has been shown to interfere with both PRL-promoting and inhibiting pathways that were involved in wound healing, including 11 PRL inhibitors and 6 PRL promoters. Our results reveal decreased PRL expression levels in VF injury, which is not in favor of the wound healing. The pathways identified may help in understanding the role of PRL as a treatment target for VF wound healing.

Piperlongumine Attenuates High Calcium/Phosphate-Induced Arterial Calcification by Preserving P53/PTEN Signaling.

Vascular calcification frequently occurs in the process of chronic kidney disease, atherosclerosis and aging, resulting in an increased prevalence of cardiovascular events. Piperlongumine (PLG) is a natural product isolated from Piper longum L. Here, we aimed to explore the effect of PLG in high calcium- and phosphate-induced vascular calcification and the associated mechanism. Flow cytometry assays showed that PLG at concentrations <10 µM did not promote vascular smooth muscle cells (VSMCs) apoptosis, and PLG at concentrations >2.5 µM inhibited VSMCs proliferation. Thus, 2.5 µM PLG was selected for subsequent experiments. Alizarin red staining and ALP activity assays showed that PLG inhibited calcium deposition of VSMCs treated with high calcium/phosphate medium. PLG also decreased the expression of osteogenic genes and proteins, including Runx2, Bmp2, and OPN, as determined by qRT-PCR and western blotting. In a vitamin D-induced aortic calcification mouse model, a 5 mg/kg dose of PLG decreased calcium deposition in the aortic wall as well as Runx2 expression. With regard to the mechanism, we found that the levels of P53 mRNA and protein in both VSMCs and mouse aortic tissues were decreased in the calcification models, and we observed that PLG preserved the levels of P53 and its downstream gene PTEN. Concurrent treatment of VSMCs with P53 ShRNA and PLG blunted the anti-calcific effect of PLG. In conclusion, PLG attenuates high calcium/phosphate-induced vascular calcification by upregulating P53/PTEN signaling in VSMCs. PLG may act as a promising herbal extract for the clinical management of vascular calcification.

Casticin inhibits breast cancer cell migration and invasion by down-regulation of PI3K/Akt signaling pathway.

Casticin is one of the major active components isolated from Fructus viticis Increasing studies have revealed that casticin has potential anticancer activity in various cancer cells, but its effects on breast cancer cell migration and invasion are still not well known. Therefore, the ability of cell migration and invasion in the breast cancer MDA-MB-231 and 4T1 cells treated by casticin was investigated. The results indicated that casticin significantly inhibited cell migration and invasion in the cells exposed to 0.25 and 0.50 µM of casticin for 24 h. Casticin treatment reduced matrix metalloproteinase (MMP) 9 (MMP-9) activity and down-regulated MMP-9 mRNA and protein expression, but not MMP-2. Casticin treatment suppressed the nuclear translocation of transcription factors c-Jun and c-Fos, but not nuclear factor-κB (NF-κB), and decreased the phosphorylated level of Akt (p-Akt). Additionally, the transfection of Akt overexpression vector to MDA-MB-231 and 4T1 cells could up-regulate MMP-9 expression concomitantly with a marked increase in cell invasion, but casticin treatment reduced Akt, p-Akt, and MMP-9 protein levels and inhibited the ability of cell invasion in breast cancer cells. Additionally, casticin attenuated lung metastasis of mouse 4T1 breast cancer cells in the mice and down-regulated MMP-9 expression in the lung tissues of mice treated by casticin. These findings suggest that MMP-9 expression suppression by casticin may act through inhibition of the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway, which in turn results in the inhibitory effects of casticin on cell migration and invasion in breast cancer cells. Therefore, casticin may have potential for use in the treatment of breast cancer invasion and metastasis.

Enantioselective total synthesis of (-)-colchicine, (+)-demecolcinone and metacolchicine: determination of the absolute configurations of the latter two alkaloids.

Here, we describe a concise, enantioselective, and scalable synthesis of (-)-colchicine (9.2% overall yield, >99% ee). Moreover, we have also achieved the first syntheses of (+)-demecolcinone and metacolchicine, and determined their absolute configurations. The challenging tricyclic 6-7-7 core of colchicinoids was efficiently introduced using an intramolecular oxidopyrylium-mediated [5 + 2] cycloaddition reaction. Notably, the synthesized colchicinoid 23 exhibited potent inhibitory activity toward the cell growth of human cancer cell lines (IC50 = ∼3.0 nM), and greater inhibitory activity towards microtubule assembly than colchicine, making it a promising lead in the search for novel anticancer agents.

Long Noncoding RNA H19/miR-675 Axis Promotes Gastric Cancer via FADD/Caspase 8/Caspase 3 Signaling Pathway.

BACKGROUND: Long noncoding RNA (lncRNA) H19 is emerging as a vital regulatory molecule in the progression of different types of cancer and miR-675 is reported to be embedded in H19's first exon. However, their function and specific mechanisms of action have not been fully elucidated. The aim of this study was to identify a novel lncRNA-microRNA-mRNA functional network in gastric cancer. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was used to assess the relative expression of H19 and miR-675 in normal (GES-1) and gastric cancer cell lines (SGC-7901, SGC-7901/DDP) as well as in tumor tissues. Gain and loss of function approaches were carried out to investigate the potential roles of H19/miR-675 in cell proliferation and apoptosis. Moreover, Fas associated via death domain (FADD) was validated to be the target of miR-675 via luciferase reporter assay. Western blotting was used to evaluate the protein expression of related signaling pathway. RESULTS: In our study H19 and miR-675 were increased in gastric cancer cell lines and tissues. Overexpression of H19 and miR-675 promoted cell proliferation and inhibited cell apoptosis, whereas knockdown of H19 and miR-675 inhibited these effects. By further examining the underlying mechanism, we showed that H19/miR-675 axis inhibited expression of FADD. FADD downregulation subsequently inhibited the caspase cleavage cascades including caspase 8 and caspase 3. CONCLUSION: Taken together, our results point to a novel regulatory pathway H19/miR-675/ FADD/caspase 8/caspase 3 in gastric cancer which may be potential target for cancer therapy.