Can drip irrigation under mulch be replaced with shallow-buried drip irrigation in spring maize production systems in semiarid areas of northern China?

BACKGROUND: In recent years, shallow-buried drip irrigation in spring maize production has gradually replaced drip irrigation under plastic films and has become a common irrigation method in semiarid areas of northern China. RESULT: Two years of field experiments were carried out in the semiarid area of western Jilin province to compare the two drip irrigation methods in the spring maize production system. The treatments included MW1 (drip irrigation under mulch + moderate irrigation amount), MW2 (drip irrigation under mulch + high irrigation amount), SM1 (shallow-buried drip irrigation + moderate irrigation amount), and SM2 (shallow-buried drip irrigation + high irrigation amount). The maize yields were significantly higher under mulch than under shallow-buried drip irrigation, but there was no interaction between mulch and the irrigation amount. Drip irrigation under mulch greatly improved spring maize N, P and K uptake compared with that under shallow-buried drip irrigation. The agronomic-use efficiency, recovery-use efficiency, and partial factor productivity were ranked in the order of MW2 > MW1 > SW2 > SW1. The water-use efficiency of drip irrigation under mulch was 7.44% and 6.82% higher than that of shallow-buried drip irrigation under the moderate and high irrigation levels, respectively. However, considering the costs of the plastic mulch, there was no significant (P < 0.05) difference in economic benefits between the SW and MW treatments. CONCLUSION: Drip irrigation under plastic film provides greater advantages for production, but shallow-buried drip irrigation may be a suitable method for farmers until fertigation technology is further optimized and the problem of plastic film pollution is solved. © 2020 Society of Chemical Industry.

LncRNA differentiation antagonizing non-protein coding RNA promotes proliferation and invasion through regulating miR-135a/NLRP37 axis in pancreatic cancer.

Background It is well-known that long-chain non-coding RNA (LncRNA) plays an important role in the development of tumor. DANCR, which is one crucial part of the lncRNA family, has been shown to be involved in the invasion of various tumors. However, its molecular mechanism in pancreatic cancer remains unknown. Methods qRT-PCR was used to detect the expression of DANCR, miR-135a mRNA in pancreatic cancer tissues or cells. E-cadherin and NLRP3 protein levels were measured by Western Blot. CCK-8, cell scratch, and transwell assays were applied to detect the proliferation and invasion of pancreatic cancer cells. Bioinformatical analysis and luciferase assay were performed to explore the relationship among DANCR, miR-135a and NLRP3. Results In pancreatic cancer, DANCR was up-regulated while miR-135a was down-regulated. The over-expression of DANCR promoted the proliferation and invasion of pancreatic cancer cells. A negative relationship was found between DANCR and miR-135a expression. Moreover, we found that miR-135a reversed the effects of DANCR in the promoting of pancreatic cancer cells, which was achieved by regulating the downstream protein of NLRP3. The correlations among DANCR, miR-135a and NLRP3 were confirmed in animal experiments. Conclusion DANCR promoted proliferation and invasion through the regulating of miR-135a / NLRP3 axis in pancreatic cancer cell. Our results suggest that DANCR may be a potential target for the therapy of pancreatic cancer.

Magnesium accumulation, partitioning and remobilization in spring maize (Zea mays L.) under magnesium supply with straw return in northeast China.

BACKGROUND: Magnesium (Mg) has important effects on maize growth, and the application of Mg fertilizer with straw return inevitably has an impact on Mg absorption in maize. RESULTS: A two-year field trial was conducted to investigate the effects of Mg fertilizers with straw return on Mg accumulations, partitioning and remobilization in maize (Zea mays L.) in northeast China. The treatments included: (i) JM3 (straw + Mg fertilizer), (ii) JM0 (straw + no Mg fertilizer), (iii) WM3 (no straw + Mg fertilizer), and (iv) WM0 (no Mg fertilizer + no straw). The results showed that the highest Mg accumulation stage in maize was prominent between the tasseling stage (VT) and blister stage (R2), and JM3 treatment accumulated 13.3% and 26.6% more Mg on average than those of the WM3 and WM0, respectively. Magnesium remobilization in distinct organs was highest in JM3 and there were significant differences between treatments. The total contribution to the grain for the JM3 treatment was higher by 6.0% and 17.9% on average than those for the WM3 and WM0, respectively. The grain yield of JM3 treatment was 0.5% and 5.3% higher than that of WM3 and WM0, respectively. CONCLUSION: Generally, these outcomes indicated that there was an interaction between Mg fertilizer and maize straw. The application of Mg fertilizer significantly promoted the accumulation, distribution to the maize organs, and the remobilization of Mg. The combination of straw return and Mg application further increased the accumulation of Mg in the grain. And all these lead to an increase in yield. © 2020 Society of Chemical Industry.

Digital droplet polymerase chain reaction analysis of common viruses in the aqueous humour of patients with Posner-Schlossman syndrome in Chinese population.

BACKGROUND: To compare the detection results consistency of quantitative polymerase chain reaction (qPCR) and digital droplet polymerase chain reaction (ddPCR), and determine the value of ddPCR for viral detection in the aqueous humour. METHODS: A total of 130 aqueous humour samples were collected, including 60 patients with Posner-Schlossman syndrome (PSS) in case group and 70 elderly patients with senile cataract in control group. The target nucleic acid fragments of human cytomegalovirus (HCMV), herpes simplex virus, Epstein-Barr virus and varicella zoster virus in aqueous humour were analysed by qPCR and ddPCR, respectively, for the diagnosis and curative effect monitoring of pathogen-induced PSS. Samples with inconsistent results were verified by next-generation sequencing. RESULTS: There were 27 and 20 HCMV-positive cases detected in the case group by ddPCR and qPCR, respectively. ddPCR increased the sensitivity for the HCMV virus detection from 400 to 100 copies/mL. No other pathogens were found in this study. The results of ddPCR were consistent with that of next generation sequencing. The mean (SD) of Lg (HCMV copies/mL) detected by ddPCR and qPCR were 1.66 (1.92) and 1.10 (1.61), respectively (P < 0.001). Compared with qPCR, results of ddPCR showed better consistency with validity of clinical treatment. All patients with ddPCR-positive results had good validity on antiviral therapy, exhibiting anterior chamber inflammation remission, resolution of corneal oedema and good IOP control within 1 month. CONCLUSIONS: HCMV was the leading cause of pathogen-induced PSS in the Chinese population. ddPCR was a promising tool for early detection, accurate diagnosis and therapeutic validity monitoring of pathogen-induced PSS. The high sensitivity of ddPCR could avoid repeated anterior chamber tap.

Laparoscopic liver hanging maneuver through the retrohepatic tunnel on the right side of the inferior vena cava combined with a simple vascular occlusion technique for laparoscopic right hemihepatectomy.

BACKGROUND: Laparoscopic hepatectomy has been performed in many hospitals, with the development of the laparoscopic operation technique. However, performing complex laparoscopic hepatectomy, such as right hemihepatectomy, is still a challenge. The aim of this study was to describe the application of a simple vascular occlusion technique and new liver hanging maneuver (LHM) in complex laparoscopic hepatectomy, which are both advocated by Chen Xiaoping for open hepatectomy. METHODS: The clinical data of 29 consecutive patients who underwent laparoscopic right hemihepatectomy (LRH) from October 2014 to October 2016 were retrospectively analyzed. During operation, the vascular occlusion technique without hilus dissection and LHM through the retrohepatic avascular tunnel on the right side of the inferior vena cava were used. RESULT: All 29 operations were successfully performed laparoscopically, while adopting Chen's methods. The study consisted of 23 patients with hepatocellular carcinoma, four patients with intrahepatic cholangiocarcinoma, and two patients with hepatic metastasis of colonic carcinoma. The tumor size was 12.4 ± 1.9 cm. The operation time of LRH was 190.3 ± 49.9 min. The intraoperative blood loss of LRH was 281.7 ± 117.8 mL; five patients required blood transfusion, and the amount of blood transfusion was 300.0 ± 89.4 mL. No case was converted to open surgery, and no death occurred. All resulted in R0 resections. The median free margin was 20.1 ± 10.8 mm. The time of postoperative oral diet intake was 2.10 ± 0.96 days. The complication rate was 17.2%. The average hospital stay after operation was 10.0 ± 2.9 days. CONCLUSION: Complex hepatectomy is a bloodless procedure that can be performed under a laparoscope safely using Chen's methods of vascular occlusion technique and LHM.

High bacterial loads of Ureaplasma may be associated with non-specific cervicitis.

BACKGROUND: Ureaplasma parvum and Ureaplasma urealyticum are commonly found in the cervix of women with non-chlamydial and non-gonococcal cervicitis or non-specific cervicitis (NSC). However their contribution to the aetiology of NSC is controversial. METHODS: U. parvum and U. urealyticum were identified and quantified in cervical swabs collected from 155 women with NSC and 312 controls without NSC, using real-time PCR. The relative bacterial quantification was then calculated using the Ureaplasma copy number divided by the number of host cells; this is important for the correction of bias linked to the number of cells harvested in different swabs. RESULTS: Ureaplasma was detected in 58.7% (91/155) of NSC patients: U. parvum in 30.3%, U. urealyticum in 16.1%, and mixed infection in 12.3%. It was also detected in 54.5% (170/312) of controls: U. parvum in 33.0%, U. urealyticum in 11.5%, and mixed infection in 9.9%. There were no significant differences for U. parvum, U. urealyticum, or mixed infection between the 2 groups (p > 0.05). However, both biovars were present at higher concentrations in NSC patients than in controls (p < 0.05). Using >10 copies/1000 cells as a reference, the positive rate of U. parvum in NSC patients was 16.1%, significantly higher than that in controls at 5.1% (relative risk 3.145, p < 0.05); positive rates of U. urealyticum in NSC patients and controls were 28.4% and 8.7%, respectively, with a statistically significant difference (relative risk 3.131, p < 0.05). CONCLUSIONS: Ureaplasma can adhere to host cells, colonize, internalize, and subsequently produce pathological lesions. A high density of Ureaplasma in the cervix may be associated with the aetiology of NSC.

Synergistic action of cavity and catalytic sites in etched Pd-Cu2O octahedra to augment the peroxidase-like activity of Cu2O nanoparticles for the colorimetric detection of isoniazid and ascorbic acid.

Despite the widespread use of nanozyme-based colorimetric assays in biosensing, challenges such as limited catalytic efficiency, inadequate sensitivity to analytes, and insufficient understanding of the structure-activity relationship still persist. Overcoming these hurdles by enhancing the inherent enzyme-like performance of nanozymes using the unique attributes of nanomaterials is still a significant obstacle. Here, we designed and constructed Pd-Cu2O nanocages (Pd-Cu2O NCs) by selectively etching the vertices of the copper octahedra to enhance the peroxidase-like (POD-like) activity of Cu2O nanoparticles. The improved catalytic activity of Pd-Cu2O NCs was attributed to their high specific surface area and abundant catalytic sites. Mechanistic studies revealed that reactive oxygen species (ROS) intermediates (•OH) were generated through the decomposition of H2O2, resulting in POD-like activity of the Pd-Cu2O NCs. The designed Pd-Cu2O NCs can oxidize 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H2O2, producing a blue oxidation product (oxTMB). The oxidation reaction was inhibited and led to a significant bleaching of the blue color in the presence of reducing substances isoniazid (INH) and ascorbic acid (AA). Based on these principles, we developed a colorimetric sensing platform for the detection of INH and AA, exhibiting good sensitivity and stability. This work provided a straightforward approach to the structural engineering of nanomaterials and the enhancement of enzyme-mimicking properties.

Inhibition of HSP20 Ameliorates Steatotic Liver Disease by Stimulating ERK2-Dependent Autophagy.

HSP20 emerges as a novel regulator of autophagy in the heart. Nonetheless, the detailed function of HSP20 in the liver and its effect on autophagy remain unknown. Here, we observed that HSP20 expression is increased in liver tissues from mice and patients with metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as nonalcoholic fatty liver disease. Liver-specific downregulation of HSP20 mitigates hepatic steatosis and insulin resistance in obese mice, while upregulating HSP20 promotes lipid deposition and hepatocyte cell death. Mechanistically, liquid chromatography-tandem mass spectrometry revealed that HSP20 interacts with phosphorylated extracellular regulated protein kinase 2 (ERK2) and prevents its dephosphorylation by dual specificity phosphatase 6, leading to ERK2-mediated repression of autophagy and resulting in aggravated saturated fatty acid (SFA)-triggered hepatocyte death. Importantly, such adverse effects could be ameliorated by ERK inhibitor. Our data reveal a framework of how HSP20 increases susceptibility of SFA-induced liver injury through enhancing ERK2 phosphorylation, which represents a plausible therapeutic intervention to combat MASLD.

An enzymatically activated AND-gate DNA logic circuit for tumor cells recognition via multi-microRNAs detection.

The DNA-based logic circuit, constructed to mimic biochemical reaction networks, is highly significant in detecting biomarkers at the molecular level. The differences in the expression levels of microRNAs (miRNAs) within different types of cells provide hope for distinguishing cell subtypes. However, reliance on a single miRNA often leads to unreliable results. Herein, we constructed an enzyme-triggered cascade logic circuit based on the AND gate, which is capable of generating corresponding fluorescence signals in the presence of target miRNAs. The introduction of apurinic/apyrimidinic (AP) sites effectively reduces the likelihood of false signal generation. Amplification of the fluorescence signal relies on the catalytic hairpin assembly and the repetitive reuse of the multicomponent nucleic acid enzyme (MNAzyme). We demonstrated that the logic circuit can not only distinguish cancer cells from normal cells but also identify different types of cancer cells. The programmability of the logic circuits and the simplicity of the assay system allow us to modify the functional sequences to recognize different types of biomarkers, thus providing a reference for the identification of various cell subtypes.

A new mutation in the human cytomegalovirus UL97 gene may confer ganciclovir resistance in Chinese kidney transplant recipients.

Mutations in the UL97 gene are the most common mechanism of human cytomegalovirus resistance to ganciclovir in transplant recipients. In this study, UL97 fragments were amplified and sequenced in 70 Chinese kidney transplant recipients who were diagnosed as having an active cytomegalovirus infection. A new mutation, C518Y, was identified in two kidney recipients, and this strain showed high-grade ganciclovir resistance by plaque reduction assay. The known mutations L595 W and C607F were detected in one recipient, but the D605E mutation was found in 42.9 % (30/70) of kidney recipients. The prevalence of this mutation was higher than that in Europe and may be associated with different regions or races.

A Simple Technique of Tunnel Constructing for Occluding Splenic Vessels During Laparoscopic Splenectomy in Patients with Cirrhosis.

Purpose: Dissecting and ligating the splenic artery is crucial for bleeding control during laparoscopic splenectomy (LS). However, for patients with portal hypertension from liver cirrhosis, it is difficult for identification and ligation because the splenic vessel is circuitous and dilated. The aim of this study was to describe a simple technique of constructing a tunnel behind the tail of the pancreas for occluding the splenic vessels during LS in patients with portal hypertension. Materials and Methods: The clinical data of 61 patients who underwent LS from April 2016 to January 2017 were retrospectively analyzed. In 27 patients, the tunnel construction (TC) behind the tail of the pancreas approach was performed owning to difficulty in dissecting and ligating the splenic artery (TC group), including 17 patients who received the TC method directly and 10 patients who received the TC method after trying to dissect the splenic artery. The remaining 34 patients underwent traditional ligating of the splenic artery (LA group). The peri- and postoperative outcomes of operative time, blood loss, conversion rate, postoperative oral diet intake, postoperative hospital stay, and postoperative complication rate of the two groups were analyzed. All the operations were completed by the same group of surgeons. Results: All 61 operations were successfully completed. Compared with patients in the LA group, patients in the TC group had less blood loss (120.37 ± 40.74 mL versus 162.65 ± 87.47 mL; t = -2.317, P = .024). There was no statistical difference of operative time, conversion rate, complication rate, postoperative hospital stays, and follow-up between the two groups. Conclusions: The technique of constructing a tunnel behind the tail of the pancreas for occluding the splenic vessels was effective and safe in those patients whose splenic artery was difficult to dissect and ligate.

Facile synthesis of core-shell Co-MOF with hierarchical porosity for enhanced electrochemical detection of furaltadone in aquaculture water.

Metal-organic frameworks (MOFs) exhibited huge application potential in electrochemical analysis field, how to facilely and effectively boost the electrochemical sensing activity of MOFs materials still face enormous challenges. In this work, core-shell Co-MOF (Co-TCA@ZIF-67) polyhedrons with hierarchical porosity was easily synthesized via simple chemical etching reaction by selecting thiocyanuric acid as the etching reagent. Benefiting from the introduction of mesopores and thiocyanuric acid/Co2+ complex on the surface of ZIF-67 frameworks, the property and functions of the pristine ZIF-67 was seriously tailored. Compared with the pristine ZIF-67, the as-resulted Co-TCA@ZIF-67 nanoparticles displayed greatly enhanced physical adsorption capacity and electrochemical reduction activity toward the antibiotic drug furaltadone. As a result, a novel furaltadone electrochemical sensor with high sensitivity was fabricated. The linear detection range was from 50 nM to 5 µM with sensitivity of 110.40 µA-1 µM-1 cm-2 and detection limit of 12 nM. This work demonstrated chemical etching strategy is truly a facile and effective way to modify the electrochemical sensing performance of MOFs-based materials, and we believed the chemically etched MOFs materials will play a stronger role in terms of food safety and environmental conservation.

Time series analysis revealed prognostic value of continuous nasopharyngeal SARS-CoV-2 nucleic acid quantification for COVID-19: A retrospective study of >3000 COVID-19 patients from 2 centers.

BACKGROUND: Early stratification of disease progression remains one of the major challenges towards the post-coronavirus disease 2019 (COVID-19) era. The clinical relevance of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid load is debated due to the heterogeneity in patients' underlying health conditions. We determined the prognostic value of nasopharyngeal viral load dynamic conversion for COVID-19. METHODS: The cycling threshold (Ct) values of 28,937 nasopharyngeal SARS-CoV-2 RT-PCRs were retrospectively collected from 3,364 COVID-19 patients during hospitalization and coordinated to the onset of disease progression. The ROC curve was utilized to determine the predictive performance of the rate of Ct value alteration between two consecutive RT-PCR runs within 48 h (ΔCt%) for disease transformation across patients with different COVID-19 severity and immune backgrounds, and further validated with 1,860 SARS-CoV-2 RT-PCR results from an independent validation cohort of 262 patients. For the 67 patients with severe COVID-19, Kaplan-Meier analysis was performed to evaluate the difference in survival between patients stratified by the magnitude of Ct value alteration between the late and early stages of hospitalization. RESULTS: The kinetics of viral nucleic acid conversion diversified across COVID-19 patients with different clinical characteristics and disease severities. The ΔCt% is a clinical characteristic- and host immune status-independent indicator for COVID-19 progression prediction (AUC = 0.79, 95 % CI = 0.76 to 0.81), which outperformed the canonical blood test markers, including c-reactive protein (AUC = 0.57, 95 % CI = 0.53 to 0.61), serum amyloid A (AUC = 0.61, 95 % CI = 0.54 to 0.68), lactate dehydrogenase (AUC = 0.61, 95 % CI = 0.56 to 0.67), d-dimer (AUC = 0.56, 95 % CI = 0.46 to 0.66), and lymphocyte count (AUC = 0.62, 95 % CI = 0.58 to 0.66). Patients with persistent high SARS-CoV-2 viral load (an increase of mean Ct value < 50 %) during the first 3 days of hospitalization demonstrated a significantly unfavorable survival (HR = 0.16, 95 % CI = 0.04 to 0.65, P = 2.41 × 10-3). CONCLUSIONS: Viral nucleic acid dynamics of SARS-CoV-2 eliminates the inter-patient variance of basic health conditions and therefore, can serve as a prognostic marker for COVID-19.

A diagnostic accuracy study comparing RNA LAMP, direct LAMP, and rapid antigen testing from nasopharyngeal swabs.

Introduction: During the coronavirus disease 2019 (COVID-19) pandemic, the early detection and isolation of individuals infected with severe acute respiratory syndrome coronavirus disease 2 (SARS-CoV-2) through mass testing can effectively prevent disease transmission. SARS-CoV-2 nucleic acid rapid detection based on loop-mediated isothermal amplification (LAMP) may be appropriate to include in testing procedures. Methods: We used 860 nasopharyngeal specimens from healthcare workers of Huashan Hospital and COVID-19 patients collected from April 7th to 21st, 2022, to assess the clinical diagnostic performance of the LAMP assay marketed by Shanghai GeneSc Biotech and compared it to the result of a rapid antigen test (RAT) head-to-head. Results: Overall, the diagnostic performance of LAMP assay and RAT were as follows. The LAMP assay represented higher sensitivity and specificity than RAT, especially in the extracted RNA samples. The sensitivity was 70.92% and 92.91% for direct LAMP and RNA-LAMP assay, respectively, while the specificity was 99.86% and 98.33%. The LAMP assay had overall better diagnostic performance on the specimens with relatively lower C t values or collected in the early phase (≤7 days) of COVID-19. The combination of LAMP assay and RAT improved diagnostic efficiency, providing new strategies for rapidly detecting SARS-CoV-2. Conclusion: The LAMP assay are suitable for mass screenings of SARS-CoV-2 infections in the general population.

Small ncRNA expression and regulation under hypoxia in neural progenitor cells.

Small non-coding RNA (ncRNA) plays critical roles in a large number of cellular processes, including neural development, cell survival and cell determination. Our previous work showed that low oxygen promoted the survival and proliferation of neural progenitor cells (NPCs) in vitro. In this study, we examine the expression and regulation of small ncRNAs in the hypoxia-driven proliferation of NPCs. The expression profiles of ncRNAs in NPCs under hypoxia were detected using microarray analysis. Results of significance analysis of microarrays (SAM) revealed that 15 small RNAs were up-regulated at least threefold and 11 were down-regulated under hypoxic conditions. The differentially expressed small ncRNAs were confirmed by quantitative RT-PCR, and miR-210 was observed to be highly expressed in NPCs under hypoxic conditions. Further study showed that hypoxia-inducible factor (HIF)-1α had a direct impact on the putative promoter regions of miR-210. From these results, we conclude that some small ncRNAs participate in the regulation of the proliferation of NPCs under hypoxia and that miR-210 is directly regulated by HIF-1α.

Direct interaction between Rab5a and Rab4a enhanced epidermal growth factor-stimulated proliferation of gastric cancer cells.

BACKGROUND: Gastric cancer (GC) is one of the leading causes of cancer-related death worldwide. Although targeted therapies such as antibodies against human epidermal growth factor receptor 2 or vascular endothelial growth factor receptor 2 have been widely used in the treatment of metastatic cancer, the overall outcomes are poor. Therefore, elucidation of the mechanism underlying cancer progression is important to improve prognosis. Overexpression of the Rab5a gene has been confirmed to correlate with tumorigenesis of many cancers, but the mechanism underling, especially of GC, is still unclear. AIM: To investigate the effects of Rab5a overexpression on the tumorigenesis of GC. METHODS: First, the expression levels of Rab5a and Rab4a in primary tumorous tissues of GC patients diagnosed between 2015 and 2018 were analyzed. Then we constructed HGC-27 cell lines overexpressing green fluorescent protein-Rab5a or red fluorescent protein-Rab4a and investigated the interaction between Rab5a or Rab4a using Western blotting, co-immunoprecipitation, confocal microscopy, and colocalization analysis. Finally, epidermal growth factor-stimulated proliferation of these cell lines was analyzed using cell counting kit-8 cell viability assay. RESULTS: Compared with normal gastric tissues, the expression levels of Rab5a and Rab4a increased progressively both in paracancerous tissues and in advanced cancerous tissues. Epidermal growth factor could promote the proliferation of HGC-27 cells, especially Rab5a-overexpressing HGC-27 cells. Notably, Rab5a and Rab4a co-overexpression promoted the proliferation of HGC-27 cells to the greatest extent. Further analysis identified a direct interaction between Rab5a and Rab4a in HGC-27 cells. CONCLUSION: Co-overexpression of Rab5a and Rab4a in GC may promote the endosomal recycling of epidermal growth factor receptor, which in turn contributes to poor prognosis and tumor progression in GC patients. Inhibition of Rab5a or Rab4a expression might be a promising therapy for refractory GC.

Intronic miR-301 feedback regulates its host gene, ska2, in A549 cells by targeting MEOX2 to affect ERK/CREB pathways.

miR-301 is localized in the first intron of ska2, whose function has not been clarified. Here, a new circuit model in which intronic miR-301 regulates the transcription and function of its host gene through a feedback mechanism has been described. Our results showed that blocking of miR-301 in A549 cells leads to a decrease in the expression of the host gene, ska2. Further analysis showed that miR-301 targets MEOX2 to affect the ERK/CREB pathway. CREB directly regulates the expression of the host gene, ska2. In addition, the inhibition of miR-301 or ska2 resulted in an increase of the mitotic index and a decrease in colony formation in soft agar, which may be related to lung tumorigenesis.

Transforming growth factor-beta-regulated miR-24 promotes skeletal muscle differentiation.

MicroRNAs (miRNAs) have recently been proposed as a versatile class of molecules involved in regulation of a variety of biological processes. However, the role of miRNAs in TGF-beta-regulated biological processes is poorly addressed. In this study, we found that miR-24 was upregulated during myoblast differentiation and could be inhibited by TGF-beta1. Using both a reporter assay and Northern blot analysis, we showed that TGF-beta1 repressed miR-24 transcription which was dependent on the presence of Smad3 and a Smads binding site in the promoter region of miR-24. TGF-beta1 was unable to inhibit miR-24 expression in Smad3-deficient myoblasts, which exhibited accelerated myogenesis. Knockdown of miR-24 led to reduced expression of myogenic differentiation markers in C2C12 cells, while ectopic expression of miR-24 enhanced differentiation, and partially rescued inhibited myogenesis by TGF-beta1. This is the first study demonstrating a critical role for miRNAs in modulating TGF-beta-dependent inhibition of myogenesis, and provides a novel mechanism of the genetic regulation of TGF-beta signaling during skeletal muscle differentiation.

Copy Number Amplification of DNA Damage Repair Pathways Potentiates Therapeutic Resistance in Cancer.

Rationale: Loss of DNA damage repair (DDR) in the tumor is an established hallmark of sensitivity to DNA damaging agents such as chemotherapy. However, there has been scant investigation into gain-of-function alterations of DDR genes in cancer. This study aims to investigate to what extent copy number amplification of DDR genes occurs in cancer, and what are their impacts on tumor genome instability, patient prognosis and therapy outcome. Methods: Retrospective analysis was performed on the clinical, genomics, and pharmacogenomics data from 10,489 tumors, matched peripheral blood samples, and 1,005 cancer cell lines. The key discoveries were verified by an independent patient cohort and experimental validations. Results: This study revealed that 13 of the 80 core DDR genes were significantly amplified and overexpressed across the pan-cancer scale. Tumors harboring DDR gene amplification exhibited decreased global mutation load and mechanism-specific mutation signature scores, suggesting an increased DDR proficiency in the DDR amplified tumors. Clinically, patients with DDR gene amplification showed poor prognosis in multiple cancer types. The most frequent Nibrin (NBN) gene amplification in ovarian cancer tumors was observed in 15 out of 31 independent ovarian cancer patients. NBN overexpression in breast and ovarian cancer cells leads to BRCA1-dependent olaparib resistance by promoting the phosphorylation of ATM-S1981 and homology-dependent recombination efficiency. Finally, integration of the cancer pharmacogenomics database of 37 genome-instability targeting drugs across 505 cancer cell lines revealed significant correlations between DDR gene copy number amplification and DDR drug resistance, suggesting candidate targets for increasing patient treatment response. Principal Conclusions: DDR gene amplification can lead to chemotherapy resistance and poor overall survival by augmenting DDR. These amplified DDR genes may serve as actionable clinical biomarkers for cancer management.

Ultrasmall HKUST-1 nanoparticles decorated graphite nanosheets for highly sensitive electrochemical sensing of DNA damage biomarker 8-hydroxy-2'-deoxyguanosine.

Herein, graphite nanosheets (GN) were first prepared through simple liquid-phase exfoliation of graphite powder in N, N-dimethylacetamide (DMAC). After then, ultrasmall Cu-based metal organic frame (HKUST-1) nanoparticles (less than 5 nm) were in-situ anchored on the surface of graphite nanosheets with high degree of dispersion. Due to the intrinsic structural advantages of the as-synthesized HKUST-1 nanoparticles decorated graphite nanosheets (HKUST-1/GN) hybrids, including superior electron transfer ability and the greatly enhanced adsorption property, HKUST-1/GN shows excellent electrochemical sensing performance toward DNA damage biomarker 8-hydroxy-2'-deoxyguanosine with fast detection speed (∼240 s), wide linear window (10 nM-1 µM), high sensitivity (346857 µA mM-1 cm-2), low detection limit (∼2.5 nM), and good reproducibility. As a result, a highly sensitive electrochemical sensing platform for the detection of DNA damage biomarker 8-hydroxy-2'-deoxyguanosine was fabricated basing the as-prepared HKUST-1/GN hybrids. What is more, the developed electrochemical method was successfully used for the detection of real samples and exhibited satisfied result.