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Background: Mangrove tannins can participate in wetland biogeochemical cycling. However, their fate and dynamics during leaf litter leaching have yet to be elucidated in coastal aquatic environments. Methods: By using a simulated microcosm experiment, changes in leaf litter mass and tannin compounds, including total phenolics (TP), extractable condensed tannins (ECT), and bound condensed tannins (BCT), were examined in the litters and leachates of four common mangrove species: Kandelia obovata (Ko), Aegiceras corniculatum (Ac), Sonneratia apetala (Sa), and Avicennia marina (Am). Results: Leaching caused a notable decline in litter mass, TP, and ECT in the leaf litter of Ko, Ac, Sa, and Am, while BCT increased significantly in Ko and Ac. Loss in foliar TP was higher than in leaf litter mass, and loss in foliar ECT was higher than in TP of Ko and Ac, but Sa showed the opposite result. The temporal changes of TP and ECT concentrations in leachates followed a similar trend, with an initial increase followed by a decrease. ECT dynamics in Ko and Ac leachates correlated with their TP concentrations, while in Sa leachate, the peak ECT occurred 72 h later than its TP peak. The leachate ECT concentrations were highest in Ac, followed by Ko, and significantly lower in Sa. The peak TP and ECT proportions in leachates accounted for 9.2–23.9% and 7.7–9.4% of the total decreases in foliar TP and ECT, respectively. Conclusion: During the leaching process, tannins' fate was species-specific, while the dynamics were almost similar. [ABSTRACT FROM AUTHOR]

The effect of annealing temperature (TA) at 600–900 °C on structure and magnetic properties of the melt-spun Sm8.6Fe85.9Co4.3Zr1.2 alloys and its nitrides was investigated. Results show that the melt-spun powder is TbCu7-type SmFe9 single phase. X-ray diffractometer (XRD) Rietveld refinement shows that the lattice parameter a increases, c and c/a decrease with the increase in TA at 600–700 °C. This is due to the tendency of nitrogen entering into the 3f site (1/2, 0, 0) during the nitridation process, which is good for the magnetic properties. The phase transforms from TbCu7-type SmFe9 to Th2Zn17-type Sm2Fe17 at above 800 °C. Scanning electron microscopy (SEM) images show that the amount of surface defects of melt-spun powder which are harmful for magnetic properties decreases at first and then increases as TA increases. The coercivity (Hcj) and maximum magnetic energy product ((BH)max) of its nitrides increase first and then decrease as a function of TA. And the remanence (Br) always shows a decrease. The optimal magnetic properties of Hcj = 748 kA·m−1, Br = 0.92 T, (BH)max = 118 kJ·m−3 are obtained by annealing at 675 °C for 2 h and then nitriding at 460 °C for 10 h. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) is a toxic non-essential heavy metal. Chronic low Cd exposure (CLCE) has been associated with distinct pathologies in many organ systems, including liver and kidney damage, osteoporosis, carcinogenicity, or reproductive toxicity. Currently, about 10% of the global population is at risk of CLCE. It is urgent to find robust and effective biomarkers for early diagnosis of Cd exposure and treatment. Metabolomics is a high-throughput method based on mass spectrometry to study the dynamic changes in a series of endogenous small molecular metabolites (typically < 1000 Da) of tissues, cells, or biofluids. It can reflect the rich and complex biochemical changes in the body after exposure to heavy metals, which may be useful in screening biomarkers to monitor exposure to environmental pollutants and/or predict disease risk. Therefore, this review focuses on the changes in metabolic profiles of humans and rodents under long-term Cd exposure from the perspective of metabolomics. Furthermore, the relationship between the disturbance of metabolic pathways and the toxic mechanism of Cd is discussed. All these information will facilitate the development of reliable metabolic biomarkers for early detection and diagnosis of Cd-related diseases. [ABSTRACT FROM AUTHOR]

Dialysis patients with erythropoietin hypo-responsiveness suffered from refractory anemia. Roxadustat reversibly binds and inhibits hypoxia-inducible factor-prolyl hydroxylase (HIF-PHD), resulting in increased endogenous EPO which stimulates erythropoiesis, theoretically has an advantage over exogenous EPO in anti-anemia therapy. From September 2019 to October 2020, 32 dialysis patients with hypo-responsiveness to erythropoietin were evaluated. During the 24-week follow-up period, all patients were taken off erythropoietin and switched to roxadustat. Dosage adjustments were administrated according to the fluctuation of hemoglobin level during the treatment. Parameters about anemia, iron metabolism and biochemical indexes were collected, and adverse events were recorded. A total of 31 patients completed the clinical observation, with varying degrees of malnutrition-inflammation. Post treatment, the levels of transferrin and total iron-binding capacity were increased, while that of transferrin saturation and cholesterol decreased. 15 cases (accounting for 48.39%, designated as fulfilled group) met the target level of hemoglobin, while 16 cases (51.61%, non-fulfilled group) did not. The baseline conditions of the above two groups were compared. The levels of hypersensitive C-reactive protein, interleukin-6 and serum ferritin in the non-fulfilled group were higher than those in the fulfilled group, and the levels of residual renal function, serum albumin, iron, transferrin and total iron-binding capacity were lower than those in the fulfilled group. Linear regression analysis showed that increase of HsCRP had a negative effect on the improvement of Hb. One case of adverse reaction grade 3 and four cases of grade 2 occurred throughout the study, yet all were relieved after therapy. Significant anti-anemia effects could be achieved in most patients with erythropoietin hypo-responsiveness after treatment with roxadustat, accompanied by relatively mild and rare adverse reactions. The malnutrition-inflammation states of patients may interfere with the anti-anemia effect of roxadustat, and iron utilization is more important than iron storage in anemia improvement. [ABSTRACT FROM AUTHOR]

To retrospectively analyze the use of artificial pneumoperitoneum in CT scans, to explore its operation methods and technical points, and to lay the foundation for the widespread application of artificial pneumoperitoneum in CT. A total of 331 patients who underwent artificial pneumoperitoneum with CT angiography from January 1, 2013, to November 1, 2019, were recruited. All patients underwent standardized artificial pneumoperitoneum in the horizontal, left and right lateral, and prone positions during CT thin-layer scans of the abdomen and 3D reconstruction. Taking the surgical results as the gold standard, and using kappa test to verify the consistency of surgical results and imaging results. In all 331 patients, 43 patients had a normal peritoneal space, and 288 patients had an abnormal peritoneal space. And only 22 patients developed complications of subcutaneous emphysema, accounting for 6.6% of all 331 patients. In terms of the postoperative results, 28 were normal, and 303 were abnormal. The sensitivity, specificity and accuracy of CT diagnosis of abdominal adhesions using artificial pneumoperitoneum were 100%, 95.04%, and 95.46%, respectively. According to the Kappa consistency test, the imaging diagnosis from the CT scan with artificial pneumoperitoneum had a high consistency with the surgical results (kappa = 0.796, P < 0.05). The technique of artificial pneumoperitoneum CT is safe, reliable, highly practical, and proficient for obtaining good imaging results. It provides a good imaging basis for the diagnosis of intra-abdominal diseases, especially intra-abdominal adhesions. [ABSTRACT FROM AUTHOR]

Background: Although stratifying individuals with respect to nasopharyngeal carcinoma (NPC) risk with Epstein-Barr virus-based markers is possible, the performance of diagnostic methods for detecting lesions among screen-positive individuals is poorly understood.Methods: The authors prospectively evaluated 882 participants aged 30 to 70 years who were enrolled between October 2014 and November 2018 in an ongoing, population-based NPC screening program and had an elevated NPC risk. Participants were offered endoscopy and magnetic resonance imaging (MRI), and lesions were identified either by biopsy at a follow-up endoscopy or further contact and linkage to the local cancer registry through December 31, 2019. The diagnostic performance characteristics of endoscopy and MRI for NPC detection were investigated.Results: Eighteen of 28 identified NPC cases were detected by both methods, 1 was detected by endoscopy alone, and 9 were detected by MRI alone. MRI had significantly higher sensitivity than endoscopy for NPC detection overall (96.4% vs 67.9%; Pdifference = .021) and for early-stage NPC (95.2% vs 57.1%; P = .021). The sensitivity of endoscopy was suggestively lower among participants who had previously been screened in comparison with those undergoing an initial screening (50.0% vs 81.2%; P = .11). The authors observed a higher overall referral rate by MRI versus endoscopy (17.3% vs 9.1%; P < .001). Cases missed by endoscopy had early-stage disease and were more commonly observed for tumors originating from the pharyngeal recess.Conclusions: MRI was more sensitive than endoscopy for NPC detection in the context of population screening but required the referral of a higher proportion of screen-positive individuals. The sensitivity of endoscopy was particularly low for individuals who had previously been screened. [ABSTRACT FROM AUTHOR]

Objective: The objective is to study the fluctuation pattern of blood glucose spectrum in patients with end-stage diabetic nephropathy (ESDN) receiving hemodialysis (HD) and peritoneal dialysis (PD), respectively, and to compare the influences of these 2 dialysis methods on glycometabolism. Methods: Sixty-four dialysis patients with ESDN were recruited, including 35 HD patients and 29 PD patients. The 24-h blood glucose on dialysis days of the 2 groups was monitored by the continuous glucose monitoring system, and the relevant glycometabolism indexes were recorded and compared. Results: The control of blood glucose in both groups was not satisfactory. At the same blood glucose level, the dosage of exogenous insulin needed by patients in the PD group was larger than that in the HD group (p < 0.05). However, the fluctuation of blood glucose and consequently the incidence of hyperglycemia and hypoglycemia in HD group were greater than that in PD group (p < 0.05). The patients' blood glucose levels decreased progressively during the course of HD. The mean blood glucose (MBG) values estimated by glycosylated hemoglobin (HbA1c) in both groups were lower than the actual measured blood glucose values (p < 0.05). Preliminary correlation analysis showed that the deviation of the MBG values estimated by HbA1c was positively correlated with the degree of anemia. Conclusion: HD patients have larger glycemic variability as compared with PD patients, while PD patients have overall increased blood glucose levels. Hypoglycemic programs should be made according to the corresponding changes in blood glucose. The HbA1c value of dialysis patients has a large deviation, so it is necessary to explore its influencing factors and develop more accurate blood glucose assessment indicators. [ABSTRACT FROM AUTHOR]

Background: Gastric cancer (GC) is one of the most common solid malignant tumors worldwide with a high-recurrence-rate. Identifying the molecular signatures and specific biomarkers of GC might provide novel clues for GC prognosis and targeted therapy.Methods: Gene expression profiles were obtained from the ArrayExpress and Gene Expression Omnibus database. Differentially expressed genes (DEGs) were picked out by R software. The hub genes were screened by cytohubba plugin. Their prognostic values were assessed by Kaplan-Meier survival analyses and the gene expression profiling interactive analysis (GEPIA). Finally, qRT-PCR in GC tissue samples was established to validate these DEGs.Results: Total of 295 DEGs were identified between GC and their corresponding normal adjacent tissue samples in E-MTAB-1440, GSE79973, GSE19826, GSE13911, GSE27342, GSE33335 and GSE56807 datasets, including 117 up-regulated and 178 down-regulated genes. Among them, 7 vital upregulated genes (HMMR, SPP1, FN1, CCNB1, CXCL8, MAD2L1 and CCNA2) were selected. Most of them had a significantly worse prognosis except SPP1. Using qRT-PCR, we validated that their transcriptions in our GC tumor tissue were upregulated except SPP1 and FN1, which correlated with tumor relapse and predicts poorer prognosis in GC patients.Conclusions: We have identified 5 upregulated DEGs (HMMR, CCNB1, CXCL8, MAD2L1, and CCNA2) in GC patients with poor prognosis using integrated bioinformatical methods, which could be potential biomarkers and therapeutic targets for GC treatment. [ABSTRACT FROM AUTHOR]

Objective: Plasma Epstein-Barr virus (EBV) DNA is considered a biomarker for nasopharyngeal carcinoma (NPC). However, its long-term role in NPC development is unclear.Materials and Methods: A total of 1363 participants seropositive for EBV VCA-IgA and EBNA1-IgA in a community-based NPC screening program in southern China were tested for plasma EBV DNA levels by real-time qPCR between 2008 and 2015. New NPC cases were confirmed by active follow-up approach and linkage to local cancer registry through the end of 2016. Cox proportional hazards regression analysis was performed to calculate the hazard ratios (HRs) for NPC risk with plasma EBV DNA.Results: Thirty patients were newly diagnosed during a median 7.5 years follow-up. NPC incidence increased with the plasma EBV DNA load ranging from 281.46 to 10,074.47 per 100,000 person-years in participants with undetectable and ≥ 1000 copies/ml levels; the corresponding cumulative incidence rates were 1.73 and 50%. Furthermore, plasma EBV DNA loads conferred an independent risk for NPC development after adjustment for other risk factors, with HRs of 7.63 for > 3-999 copies/ml and 39.79 for ≥1000 copies/ml. However, the HRs decreased gradually after excluding NPC cases detected in the first 2 to 3 years and became statistically nonsignificant by excluding cases detected during the first 4 years.Conclusion: Elevated plasma EBV DNA can predict NPC risk over 3 years. Monitoring plasma EBV DNA can be used as a complementary approach to EBV serological antibody-based screening for NPC. [ABSTRACT FROM AUTHOR]

IL24 mRNA is known to have an apoptotic effect on cancer cells but not on noncancer cells. However, the expression level of the IL24 mRNA in head and neck squamous cell carcinoma (HNSCC) and its subgroups is rarely studied. In this study, the clinical implication of IL24 mRNA was evaluated in the common subgroups of HNSCC, including oral squamous cell carcinoma (OSCC), nasopharyngeal carcinoma (NPC), and laryngeal squamous cell carcinoma (LSCC) for analysis. Substantial IL24 mRNA expression data were calculated from several databases, such as the Gene Expression Omnibus (GEO), ArrayExpress, Sequence Read Archive (SRA), ONCOMINE, and The Cancer Genome Atlas (TCGA) databases. We ultimately collected a total of 41 microarrays and RNA-seq including 1,564 HNSCC and 603 noncancer tissue samples. IL24 mRNA was highly expressed in OSCC, LSCC, and NPC as shown by the separated standard mean difference (SMD), as well as HNSCC as a whole part (SMD = 1.47, 95% confdence interval (CI) = 1.24−1.70, P < 0.0001). In all subgroups, the IL24 mRNA upregulation had the ability to distinguish cancer from noncancer tissue with area under the curves (AUCs) of the summary receiver operating characteristic (sROC) higher than 0.85. In conclusion, IL24 mRNA may be used as a potential marker for cancer screening, and its clinical diagnostic value needs to be further studied. It also provides a new idea for the treatment of the IL24 gene in HNSCC and its subgroups in the future. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the factors that affect 30-day mortality of patients with HAP. The data used in this study were collected from all HAP occurred in our hospital between January 2014 and December 2017. A total of 1158 cases were included. 150 (13.0%) of whom died within 30 days. This reported mortality identified by the univariate Cox regression analysis is found to have been affected by the following factors: age greater than 70 years, presence of diabetes mellitus and chronic obstructive pulmonary disease, gastric tube intubation, administration of proton-pump inhibitor, blood albumin level less than 30 g/l, elevated neutrophil-to-lymphocyte ratio, antibiotics therapy in the preceding 90 days, intensive care unit (ICU) admission, blood lymphocyte count less than 0.8 × 109/L, elevated blood urea nitrogen/albumin (BUN/ALB) level, and presence of multidrug-resistant (MDR) pathogens. In the second multivariate analysis, administration of proton-pump inhibitor, administration of antibiotics in the preceding 90 days, ICU admission, blood lymphocyte count less than 0.8 × 109/L, elevated BUN/ALB level, and presence of MDR pathogens were still associated with 30-day mortality. The area under the receiver operating characteristic curves in the BUN/ALB predicting 30-day mortality due to HAP was 0.685. A high BUN/ALB was significantly associated with a worse survival than a low BUN/ALB P<0.001. Therefore, an elevated BUN/ALB level is a risk factor for mortality on patients with HAP. [ABSTRACT FROM AUTHOR]

Tumor-associated macrophages (TAMs) with M2 phenotype play an essential role in tumor microenvironment (TME) during the progression and development of numerous cancers and associated with poor prognosis. Thus, regulation of TAMs polarization emerged as a new strategy for tumor immune therapy. According to Traditional Chinese Medicine (TCM) theory, herbs with Qi-tonifying character are involved in improving the defense capacity of immune system. In this study, we screened extracts and ingredients from five Qi-tonifying herbs exhibiting an inhibitory effect on M2 polarization of murine macrophages RAW264.7 induced by IL-4 and IL-13. Among these candidates, total flavonoids from Glycyrrhiza Radix et Rhizoma (TFRG) and ethanol extract of Ginseng Radix et Rhizoma significantly inhibited the expression of Arginase-1 (Arg-1) (above 90% at 100μg/mL), one of the phenotype markers of M2 macrophages. The inhibition of total saponins of Ginseng Radix et Rhizoma, ethanol extract of Cordyceps, ethanol extract of Acanthopanacis senticosi Radix et Rhizoma Seu caulis, and ethanol extract of Astragali Radix reached above 50% at 100μg/mL. The inhibition of ingredients including glabridin, isoliquiritin apioside, lysionotin, cordycepin, astragaloside IV, and calycosin reached above 50% at 50μM. Then, we investigated the molecular mechanisms of TFRG. TFRG abolished the migration of murine breast cancer 4T1 stimulated by the conditioned medium from M2 macrophages (M2-CM). In addition to Arg-1, TFRG also antagonized the IL-4/13-mediated mRNA upregulation of the M2 markers including found in inflammatory zone 1 (FIZZ1), chitinase-3-like protein 3 (YM1), and mannose receptor (CD206) and upregulated the expression of inducible nitric oxide synthase (iNOS), one of the M1 markers. The further exploration showed that TFRG decreased the phosphorylation of STAT6 and increased the expression of miR-155. Our study provides a series of potential immune regulating natural products from five Qi-tonifying herbs on M2 phenotype. For instance, TFRG suppressed M2 polarization of macrophages partly by inactivating STAT6 pathway and enhanced the level of miR-155 to regulate the expressions of M1 and M2 markers. [ABSTRACT FROM AUTHOR]

Hedyotis diffusa Willd and Scutellaria barbata D. Don (HDSB) were the core couplet in medicines that were commonly used for the purpose of anti-inflammation and anticancer treatments in China. However, biological properties of this couplet have not been fully elucidated. In this study, we screened fractions of HDSB for their anti-inflammatory activities and explored pertinent molecularmechanisms onmurinemacrophage RAW264.7 cell model. Ethyl acetate fraction fromthe aqueous extract of the couplet at equalweight ratio (EA11) showed the strongest inhibition of the nitrite accumulation in supernatant of RAW264.7 cells stimulated with lipopolysaccharide (LPS)/IFN-γ (interferon-γ). In addition, EA11 inhibited iNOS and IL-1γ expression in a concentrationdependent manner while promoting the expression of HO-1 and PPAR-γ. Anti-inflammatory capability is most likely facilitated by its inhibitory effect on JNK signaling pathway and miR-155 expression. This study suggests that EA11 may be represented as a potential anti-inflammatory therapeutic candidate. [ABSTRACT FROM AUTHOR]

EZH2, a histone H3 lysine-27-specific methyltransferase, is involved in diverse physiological and pathological processes including cell proliferation and differentiation. However, the role of EZH2 in liver fibrosis is largely unknown. In this study, it was identified that EZH2 promoted Wnt pathway-stimulated fibroblasts in vitro and in vivo by repressing Dkk-1, which is a Wnt pathway antagonist. The expression of EZH2 was increased in CCl4-induced rat liver and primary HSCs as well as TGF-β1-treated HSC-T6, whereas the expression of Dkk1 was reduced. Silencing of EZH2 prevented TGF-β1-induced proliferation of HSC-T6 cells and the expression of α-SMA. In addition, knockdown of Dkk1 promoted TGF-β1-induced activation of HSCs. Moreover, silencing of EZH2 could restore the repression of Dkk-1 through trimethylation of H3K27me3 in TGF-β1-treated HSC-T6 cells. Interestingly, inhibition of EZH2 had almost no effect on the activation of HSC when Dkk1 was silenced. Collectively, EZH2-mediated repression of Dkk1 promotes the activation of Wnt/β-catenin pathway, which is an essential event for HSC activation. [ABSTRACT FROM AUTHOR]

Cycloid is a new tooth profile (TP) to improve the meshing performance of harmonic drive. A new complex cycloid TP with a variable TP angle is suggested, which not only improves the meshing state but also promotes the fitting capacity of the cycloid. After the theoretical TP of circular spline described by discrete points is solved by envelope method, the suitability of using complex cycloid to fit it is verified. Then, a fitting model is built in which the objective function is set to minimize the summation of the distances between the points and fitted curves, and a penalty function is used to achieve one-side fitting approximation. Complex Method is introduced to solve this model. At last, the motion simulation and backlash distribution show that the new cycloid TP with appropriate TP angle has better mesh performance. [ABSTRACT FROM AUTHOR]

Based on morphological evidence and DNA sequencing, we propose three new species of the basidiomycete family Boletaceae, namely Aureoboletus venustus, Leccinellum onyx, and Pulveroboletus sinensis. The species were collected from the Heishiding Nature Reserve in Guangdong Province, China. The descriptions are illustrated by photographs and line drawings, and comparisons were made with related species. Morphologically, A. venustus is characterized by its mucilaginous pileus with red to reddish orange color, a vivid yellow hymenophore surface, and small ellipsoid basidiospores (7) 7.5-10.5 (12) × 5-6 (7) μm in size. Leccinellum onyx is characterized by its slightly areolating pileus with grayish orange to brownish orange color, a grayish brown to light grayish orange hymenophore surface, short yellowish white tubes, a yellowish white to brownish gray stipe covered with dark brown warts, and small ellipsoid basidiospores with a size of (8) 9-11 (12) × (4) 5-6 μm. Its nucleotide sequence of the internal transcribed spacer (ITS) region is particularly long (1080 bp) in comparison to related species. Pulveroboletus sinensis is characterized by its yellow to vivid yellow pulverulent pileus covered with deep orange to brownish orange conico-pyramidal scales, an appendiculate margin, greenish yellow tubes easily becoming cyanescent upon bruising, a yellow to vivid yellow stipe covered with yellow to brownish orange conico-floccose scales, and small smooth ellipsoid basidiospores with a size of (6) 6.5-8.5 (11) × (4.5) 5-6 (6.5) μm. Phylogenetic analysis of nucleotide sequences of the ITS region and the nuclear large subunit ribosomal RNA gene (nrLSU) provided further evidence that the described mushrooms represent new species. [ABSTRACT FROM AUTHOR]

The mechanism of HH σ bond activation catalyzed by VO [ABSTRACT FROM AUTHOR]

PURPOSE: To construct a lentiviral eukaryotic expression vector containing two genes of cbfal and satb2. METHODS: The aim genes of cbfal and satb2 were amplified from plasmids by PCR. After TA cloning, the positive clones were identified by restrictive enzyme digestion and commercial DNA sequencing. Cbfal and satb2 with correct sequences were ligated upstream and downstream to pIRES, respectively, to construct pIRES -cbfal -satb2. Then cbfal -Ires -satb2 fragment was obtained by double digestion, and inserted into corresponding enzyme cut sites of pLentinTrident1--CMV which had been added resistance gene neo/kana to construct the lentiviral eukaryotic expression vector pLentinTrident1-CMV-cbfal -Ires-satb2. RESULTS: We amplified the genes cbfal and satb2 by PCR and connected them with pLentinTridentl -CMV by internal ribosomal entry site of mediator pIRES successfully. The result was identified by PCR, restrictive enzyme digestion and sequencing. CONCLUSIONS: Recombinant lentiviral eukaryotic expression vector containing both cbfal and satb2 genes is successfully constructed. This provides a foundation for further studies on their functions. Supported by Programs for Science and Technology Development of Shandong Province (2009GG10002052). [ABSTRACT FROM AUTHOR]

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How to obtain intersection of curves and surfaces is a fundamental problem in many areas such as computer graphics, CAD/CAM, computer animation, and robotics. Especially, how to deal with singular cases, such as tangency or superposition, is a key problem in obtaining intersection results. A method for solving the intersection problem based on the coordinate transformation is presented. With the Lagrange multiplier method, the minimum distance between the center of a circle and a quadric surface is given as well. Experience shows that the coordinate transformation could significantly simplify the method for calculating intersection results. The location of the tangent point is revised according to the tangency condition. It can improve the stability of the intersection of given curves and surfaces in singularity cases. The new algorithm is applied in a three dimensional CAD software (GEMS), produced by Tsinghua University. [ABSTRACT FROM AUTHOR]