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BACKGROUND: Hypocalcemia is highly common in hospitalized patients, especially in those with trauma, On the other hand, abnormal calcium metabolism is an important metabolic challenge; however, it is often neglected and untreated, and certain factors may induce serious neurological and cardiovascular complications. AIM: To retrospectively analyze the impact of hypocalcemia on the prognosis of patients with multiple traumas. METHODS: The study was conducted from January 2020 to December 2021. Ninety-nine patients with multiple injuries were treated at the critical care medicine department of Fuyang People's Hospital. The selected indicators included sex, age, and blood calcium and hematocrit levels. Many indicators were observed, including within 24 h of hospitalization, and the prognosis was collected after 28 d. Based on the blood calcium levels, the patients were divided into the following two groups: Normocalcemia and hypocalcemia. Of the 99 patients included, 81 had normocalcemia, and 18 had hypocalcemia. Separate experiments were conducted for these two groups. RESULTS: There was an association between serum calcium levels and the prognosis of patients with polytrauma. CONCLUSION: Clinically, the prognosis of patients with multiple traumas can be preliminarily evaluated based on serum calcium levels.

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Heart failure (HF) can be caused by a variety of causes characterized by abnormal myocardial systole and diastole. Ca2+ current through the L-type calcium channel (LTCC) on the membrane is the initial trigger signal for a cardiac cycle. Declined systole and diastole in HF are associated with dysfunction of myocardial Ca2+ function. This disorder can be correlated with unbalanced levels of phosphorylation / dephosphorylation of LTCC, endoplasmic reticulum (ER), and myofilament. Kinase and phosphatase activity changes along with HF progress, resulting in phased changes in the degree of phosphorylation / dephosphorylation. It is important to realize the phosphorylation / dephosphorylation differences between a normal and a failing heart. This review focuses on phosphorylation / dephosphorylation changes in the progression of HF and summarizes the effects of phosphorylation / dephosphorylation of LTCC, ER function, and myofilament function in normal conditions and HF based on previous experiments and clinical research. Also, we summarize current therapeutic methods based on abnormal phosphorylation / dephosphorylation and clarify potential therapeutic directions.

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A regiodivergent allylation of 1H-indoles highly selectively at the C3 and N1 positions with ß-acyl allylic sulfides through desulfurative C-C/C-N bond-forming reactions has been developed under mild conditions. Notably, the remarkable site-selective switch can be achieved by a delicate choice of solvents and bases. This cost-efficient method displays a broad substrate scope, good functional compatibility, and excellent site-selectivity, thus offering a divergent synthesis of indole substituted α-branched enones, which possess diverse potential opportunities for further applications and derivatization.

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The three provinces of Northeast China are crucial to national commodity grain production. Soils in those areas have begun to severely degrade after long-term high-intensity use, with wind erosion as one of the main reasons. Based on meteorological and soil data from 1981 to 2019, we evaluated the spatial-temporal characteristics of wind erosion on bare land in the three provinces of Northeast China by using the revised wind erosion equation (RWEQ), and analyzed the contributions of meteorological factors to wind erosion on bare land. The results showed that, the meteorological factors of wind erosion were overall high in southwestern part and low in northeastern part of the region. In general, wind erosion in the region was substantial, especially in Liaoning. During the 39 years, wind erosion significantly increased throughout the whole year and during the growing season, at a rate of 129 and 105 t·km-2 per decade, respectively. The obvious increase in wind erosion was observed in the northwest Liaoning, Liaohe Plain, and Changbai Mountain area. Wind speed and air temperature were the main factors affecting wind erosion during the year and non-growing season, which contributed less during the growing season when precipitation contributed the most. We concluded that climate change has aggravated soil wind erosion in the three provinces of Northeast China.

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BACKGROUND AND AIMS: Exposure to heavy metals has been widely recognized as a risk factor for human health. However, there is limited information on the effects of blood heavy metals on gallstones. This study aims to investigate the relationship between blood heavy metals and gallstones using data from the National Health and Nutrition Examination Survey (NHANES). METHODS: 7192 participants aged 20 years or older with complete information were included in the study. Serum concentrations of heavy metals were determined by inductively coupled plasma kinetic reaction cell mass spectrometry. Gallstones were presented by standard questionnaires. Logistic regression, nonlinear, subgroup, and sensitivity analyses were used to estimate the association between blood heavy metals and gallstones. RESULTS: Multivariate logistic regression showed that the highest quintile of blood selenium (Se) was associated with a higher risk of gallstones compared with the lowest quintile (OR = 1.66, 95% CI: 1.16-2.36), particularly in individuals who were under 65 years of age, females, non-Hispanic Whites, non-drinkers, obese, and had a college education or higher. There was no correlation between blood cadmium (Cd), mercury (Hg), lead (Pb), manganese (Mn), and gallstones in the total population. Restricted cubic spline curves showed that a negative correlation was observed between blood Cd (OR = 0.84, 95% CI: 0.710-1.00), Hg (OR = 0.87, 95% CI: 0.78-0.97) and gallstones when Cd < 0.302 µg/L and Hg < 3.160 µg/L. CONCLUSIONS: Blood Se was an independent risk factor for gallstones, particularly in individuals under 65 years old, females, non-Hispanic Whites, non-drinkers, obese, and had a college education or higher. Furthermore, blood Cd and Hg were associated with a reduced risk of gallstones within a certain range.

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OBJECTIVE@#To observe the effects of electroacupuncture at "Siguan" points on behavior, colonic 5-hydroxytryptamine (5-HT) and fecal short-chain fatty acids (SCFAs) in rats with post-stroke depression (PSD), and explore the effect mechanism of electroacupuncture at Siguan points on PSD.@*METHODS@#Fifty SD rats were randomly divided into a sham-operation group, a stroke group, a PSD group, a drug group and an electroacupuncture group, with 10 rats in each one. The stroke model was established by middle cerebral artery occlusion (MCAO) method in the stroke group; except for the sham-operation group, the rats in the other groups were intervened with MCAO combined with solitary and chronic unpredictable mild stress (CUMS) to establish PSD model. In the electroacupuncture group, electroacupuncture was delivered at "Hegu" (LI 4) and "Taichong" (LR 3), with disperse-dense wave, 2 Hz/10 Hz in frequency, for 30 min in each intervention, once daily, for consecutive 21 days. Simultaneously, distilled water (0.01 L•kg-1•d-1) was administrated intragastrically. Fluoxetine solution (2.33 mg•kg-1•d-1) was given by gavage , once a day and for 21 days in the drug group. The same procedure of fixation and gavage with distilled water were adopted in the sham-operation group, the stroke group and the PSD group. Separately, before stroke modeling, after PSD modeling and after 21-day intervention, the consumption of sugar water and the scores of horizontal movement and vertical movement in open-field test were observed. After 21-day intervention, the content of colonic 5-HT was detected by immunohistochemical method, and that of fecal SCFAs was determined by gas chromatography mass spectrometry.@*RESULTS@#After PSD modeling, compared with the stroke group, the sugar water consumption, the horizontal movement scores and vertical movement scores of the open-field test were all reduced in the PSD group, the drug group and the electroacupuncture group (P<0.05). After 21-day intervention, the sugar water consumption and the scores of horizontal movement and vertical movement of the open-field test were increased in the drug group and the electroacupuncture group (P<0.05) when compared with the PSD group; and the horizontal movement score in the electroacupuncture group was lower than that of the drug group (P<0.05). Compared with the sham-operation group, the contents of total fecal SCFAs and acetic acid were lower in the stroke group (P<0.05), and the contents of colonic 5-HT and total fecal SCFAs, acetic acid, propionic acid and butyric acid were reduced in the PSD group (P<0.05). In comparison with the PSD group, the contents of colonic 5-HT and total fecal SCFAs, acetic acid and propionic acid were increased in the drug group and the electroacupuncture group (P<0.05); and the content of colonic 5-HT in the electroacupuncture group was lower than that of the drug group (P<0.05). The level of colonic 5-HT was positively correlated with the contents of total fecal SCFAs and propionic acid (r=0.424, P=0.005; r=0.427, P=0.004).@*CONCLUSION@#Electroacupuncture at "Siguan" points can relieve the depression-like behavior of PSD rats, and its underlying mechanism may be related to the regulation of fecal SCFAs, which affects the release of colonic 5-HT.

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Objective To investigate the change in mucosal-associated invariant T (MAIT) lymphocytes in peripheral blood of children with metabolic associated fatty liver disease (MAFLD) and its clinical significance. Methods A total of 18 children with MAFLD who attended Hunan Children's Hospital from March to May, 2022, were enrolled as MAFLD group, and 20 normal children who attended the hospital during the same period of time were enrolled as control group. Peripheral blood samples were collected, and flow cytometry was used to measure the percentages of MAIT lymphocytes (CD3 + CDl61 + TCRVα7.2 + cells), different MAIT lymphocyte subsets (CD4 + CD8 - MAIT cells, CD4 - CD8 - MAIT lymphocytes, CD4 - CD8 + MAIT lymphocytes, and CD4 + CD8 + MAIT lymphocytes), and MAIT lymphocytes expressing PD-1, CD69, perforin, CD107α, CXCR3, CXCR6, and CCR6. The correlation of MAIT lymphocyte frequency with liver inflammation, fat content, and fibrosis degree was analyzed. The t -test was used for comparison of normally distributed continuous data between two groups, and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups. The Spearman correlation analysis was used for correlation analysis. Results Compared with the control group, the MAFLD group had significant increases in the percentage of MAIT lymphocytes in peripheral blood, the percentages of MAIT cells expressing PD-1, CD69, CD107α, CXCR3, CXCR6 and CCR6, and the percentages of CD4 + CD8 - MAIT cells and CD4 + CD8 + MAIT lymphocytes among MAIT cell subsets (all P < 0.05), as well as a significant reduction in the percentage of CD4 - CD8 + MAIT cells among MAIT cell subsets ( P < 0.001). The percentages of CD4 + CD8 + MAIT lymphocytes and CD107α-positive MAIT lymphocytes were negatively correlated with alanine aminotransferase ( r =-0.474 and -0.550, P =0.047 and 0.018). Conclusion The migration of peripheral blood MAIT lymphocytes to the liver plays a protective role against liver inflammation in children with MAFLD.

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Objective: To evaluate the diagnostic value of transient elastography, aspartate aminotransferase-to-platelet ratio index (APRI), and fibrosis index based on 4 factors (FIB-4) for liver fibrosis in children with non-alcoholic fatty liver disease (NAFLD). Methods: A retrospective study was conducted on 100 cases of nonalcoholic fatty liver disease in Hunan Children's Hospital between August 2015 to October 2020 to collect liver tissue pathological and clinical data. The receiver operating characteristic curve (ROC curve) was used to analyze the diagnostic value of liver stiffness measurement (LSM), APRI and FIB-4 in the diagnosis of different stages of liver fibrosis caused by NAFLD in children. Results: The area under the ROC curve (AUC) value of LSM, APRI and FIB-4 for diagnosing liver fibrosis (S≥1) were 0.701 [95% confidence interval (CI): 0.579 ~ 0.822, P = 0.011], 0.606 (95%CI: 0.436 ~ 0.775, P = 0.182), and 0.568 (95%CI: 0.397 ~ 0.740, P = 0.387), respectively. The best cut-off values were 6.65 kPa, 21.20, and 0.18, respectively. The AUCs value of LSM, APRI, and FIB-4 for diagnosing significant liver fibrosis (S≥ 2) were 0.660 (95% CI: 0.552 ~ 0.768, P = 0.006), 0.578 (95% CI: 0.464 ~ 0.691, P = 0.182) and 0.541 (95% CI: 0.427 ~ 0.655, P = 0.482), respectively. The best cut-off values were 7.35kpa, 24.78 and 0.22, respectively. The AUCs value of LSM, APRI and FIB-4 for the diagnosis of advanced liver fibrosis (S≥ 3) were 0.639 (95% CI: 0.446 ~ 0.832, P = 0.134), 0.613 (95% CI: 0.447 ~ 0.779, P = 0.223) and 0.587 (95% CI: 0.411 ~ 0.764, P = 0.346), respectively. The best cut-off values were 8.55kpa, 26.66 and 0.27, respectively. Conclusion: The transient elastography technique has a better diagnostic value than APRI and FIB-4 for liver fibrosis in children with NAFLD.

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Ergothioneine (ERG) is a natural antioxidant that has been widely used in the fields of food, medicine and cosmetics. Compared with traditional plant extraction and chemical synthesis approaches, microbial synthesis of ergothioneine has many advantages, such as the short production cycle and low cost, and thus has attracted intensive attention. In order to engineer an ergothioneine high-yielding Escherichia coli strain, the ergothioneine synthesis gene cluster egtABCDE from Mycobacterium smegmatis and egt1 from Schizosaccharomyces pombe were introduced into E. coli BL21(DE3) to generate a strain E1-A1 harboring the ergothioneine biosynthesis pathway. As a result, (95.58±3.2) mg/L ergothioneine was produced in flask cultures. To further increase ergothioneine yield, the relevant enzymes for biosynthesis of histidine, methionine, and cysteine, the three precursor amino acids of ergothioneine, were overexpressed. Individual overexpression of serAT410STOP and thrA resulted in an ergothioneine titer of (134.83±4.22) mg/L and (130.26±3.34) mg/L, respectively, while co-overexpression of serAT410STOP and thrA increased the production of ergothioneine to (144.97±5.40) mg/L. Eventually, by adopting a fed-batch fermentation strategy in 3 L fermenter, the optimized strain E1-A1-thrA-serA* produced 548.75 mg/L and 710.53 mg/L ergothioneine in glucose inorganic salt medium and rich medium, respectively.

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A built-in electric field in electrocatalyst can significantly accumulate higher concentration of NO3 - ions near electrocatalyst surface region, thus facilitating mass transfer for efficient nitrate removal at ultra-low concentration and electroreduction reaction (NO3 RR). A model electrocatalyst is created by stacking CuCl (111) and rutile TiO2 (110) layers together, in which a built-in electric field induced from the electron transfer from TiO2 to CuCl (CuCl_BEF) is successfully formed . This built-in electric field effectively triggers interfacial accumulation of NO3 - ions around the electrocatalyst. The electric field also raises the energy of key reaction intermediate *NO to lower the energy barrier of the rate determining step. A NH3 product selectivity of 98.6 %, a low NO2 - production of <0.6 %, and mass-specific ammonia production rate of 64.4 h-1 is achieved, which are all the best among studies reported at 100 mg L-1 of nitrate concentration to date.

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PURPOSE: Hepatocellular carcinoma (HCC) usually occurs accompanied by portal hypertension. Transcatheter arterial chemoembolization (TACE) is recommended as an effective treatment in HCC. Recent studies had conflicting results regarding the effectiveness and safety of TACE for HCC in patients with transjugular intrahepatic portosystemic shunt (TIPS). This meta-analysis aimed to evaluate the influence of TIPS on the effectiveness and safety of TACE for patients with HCC. METHODS: A comprehensive search of studies among PubMed, Web of Science and Cochrane Library was conducted, from the earliest publishing date to January 27th, 2020. Statistical analyses were all performed using the Stata 13.0 software. I2 index statistic was used to assess heterogeneity. RESULTS: Six studies with a total of 536 patients with HCC were included in the analysis. The pooled response rate was 51% (95% CI: 25% to 77%) with a significant heterogeneity (I2=93.3%, p < 0.001). The TACE + TIPS group had an inferior response rate than the non-TIPS group, but the difference had no statistical significance (p = 0.171) and heterogeneity was low (I2=0.00%, p = 0.490). Pooled hepatic failure rate was 8.8% (95% CI: 5.2% to 12.4%) with low heterogeneity (I2=0.0%, p = 0.747). But the pooled hepatic failure rate increased to 12.7% (95% CI: 5.7% to 19.7%) with low heterogeneity (I2=11.5%, p = 0.323) if the patients who received TIPS after TACE were excluded. CONCLUSION: TIPS does not influence the effectiveness of TACE, but attention should be paid to the risk of hepatic failure.

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Herein, we report a palladium-catalyzed dehydrogenative cross-coupling of indoles with cyclic enones to give ß-indolyl cyclic enones under mild and neutral reaction conditions. The key to the success is to explore a mild condition, which ensures the indole C-H activation and subsequent syn ß-hydride elimination through rapid enolization isomerization of Pd(II)-enolate while suppressing other undesired side reactions. Synthetic utility has also been demonstrated in the flexible transformation of the coupling products to meta-phenols and benzo[a]carbazoles.

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BackgroundSARS-CoV-2 is a novel human coronavirus, there is no specific antiviral drugs. It has been proved that host-cell-expressed CD147 could bind spike protein of SARS-CoV-2 and involve in host cell invasion. Antibody against CD147 could block the infection of SARS-CoV-2. We aimed to assess the efficacy and safety of meplazumab, a humanized anti-CD147 antibody, as add-on therapy in patients with COVID-19 pneumonia. MethodsAll patients received recommended strategy from Diagnosis and Treatment for 2019 Novel Coronavirus Diseases released by National Health Commission of China. Eligible patients were add-on administered 10 mg meplazumab intravenously at days 1, 2, and 5. Patients hospitalized in the same period were observed as concurrent control. The endpoints include virological clearance rate, case severity, chest radiographic, and laboratory test. This trial was approved by the Ethics Committee of Institution at the Tangdu hospital, and registered with ClinicalTrials.gov, NCT 04275245. Findings17 patients were enrolled and assigned to meplazumab group between Feb 3, 2020 and Feb 10, 2020. 11 hospitalized patients served as concurrent control. Baseline characteristics were generally balanced across two groups. Compared to control group, meplazumab treatment significantly improved the discharged (p=0.006) and case severity (p=0.021) in critical and severe patients. The time to virus negative in meplazumab group was reduced than that in control group (median 3, 95%CI[1.5-4.5] vs. 13, [6.5-19.5]; p=0.014, HR=0.37, 95%CI[0.155-0.833]). The percentages of patients recovered to the normal lymphocyte count and CRP concentration were also increased remarkably and rapidly in meplazumab group. No adverse effect was found in meplazumab-treated patients. InterpretationMeplazumab efficiently improved the recovery of patients with SARS-CoV-2 pneumonia with a favorable safety profile. Our results support to carry out a large-scale investigation of meplazumab as a treatment for COVID-19 pneumonia. FundingNational Science and Technology Major Project.

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Objective:To investigate the etiology, prognosis and prognostic factors of pediatric acute liver failure(PALF), in order to provide the basis for clinical treatment of PALF.Methods:The clinical data of children with PALF hospitalized at Hunan Children′s Hospital from May 2008 to May 2018 were collected, and the causes and prognosis were analyzed.According to the prognosis, the patients were divided into the death group and the survival group, whose biochemical indexes were then compared.After that, the statistical analysis of different data were carried out by using t-test, Wilcoxon test and χ2 test separately. Results:In 120 PALF cases, there were 68 males and 52 females, and there were 36 infants, 34 toddlers, 22 preschoolers and 28 school-age children.Twenty cases (16.7%) were caused by sepsis, 19 cases (15.8%) by genetic metabolic diseases, 18 cases (15.0%) by poisoning, 12 cases (10.0%) by viral infection, 6 cases (5.0%) by drugs, 1 case (0.8%) by bile polyp, and 1 case (0.8%) by tumor disease.Besides, the etiology of 43 cases (35.9%) was unknown.Among the cases with known etiologies, genetic metabolic and infectious diseases were the main cause of disease in infants, toddler patients were mostly caused by infectious diseases and drug/toxicants, and drug/toxicants and hereditary metabolic diseases were the dominant cause of disease in school-age children and preschoolers.Mortality rate of children with PALF was 50.0%.Among them, the mortality of Epstein-Barr virus-associated hemophagocytic syndrome, sepsis, Citrin deficiency and Tyrosinemia was higher than that of other diseases.Compared with the survival group, the total bilirubin (TB)[159.00(73.05, 274.00) μmol/L vs.62.75(2.65, 221.75)μmol/L], direct bilirubin(DB)[83.00(41.43, 160.00) μmol/L vs.38.74(10.98, 128.75) μmol/L], prothrombin time (PT)[39.60(24.93, 62.60) s vs.24.65(21.43, 29.83) s], international standardized ratio (INR)[3.40(2.30, 6.74) vs.2.09(1.85, 2.84)], and blood ammonia (NH 3) levels [109.50(85.25, 149.75) μmol/L vs.80.00(60.25, 102.75) μmol/L] in the death group were significantly increased, and the diffe-rences were statistically significant(all P<0.05); while the levels of albumin[(28.72±5.88) g/L vs.(33.69±4.96) g/L], alanine aminotransferase (ALT) [586.50(223.25, 1 082.00) U/L vs.1 434.00(615.00, 3 334.50) U/L]and aspartate aminotransferase (AST) [827.50(545.00, 2 024.00) U/L vs.1 663.50(821.00, 4 886.75) U/L]in the death group were significantly decreased, and the differences were statistically significant(all P<0.05). However, the blood glucose and cholesterol levels in both groups had no statistically significant difference. Conclusion:The mortality of children with PALF is high, and different age groups have different etiologies.The increase of TB, DB, PT, INR, NH3 and the ratio of hepatic encephalopathy, and the decrease of albumin, AST and ALT suggest poor prognosis.

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Enterokinase is a class of serine proteases that specifically recognize the cleavage DDDDK sequences. Therefore, enterokinase has been widely used as a tool enzyme in the field of biomedicine. Currently, the expression level of enterokinase in Pichia pastoris is low, which hinders related practical applications. In this study, the effects of six different signal peptides SP1, SP2, SP3, SP4, SP7 and SP8 on the secretory expression of enterokinase in Pichia pastoris were studied. Compared with α-factor, SP1 significantly increased the secretory expression of enterokinase (from 6.8 mg/L to 14.3 mg/L), and the enterokinase activity increased from (2 390±212) U/mL to (4 995±378) U/mL in shaking flask cultures. On this basis, the enterokinase activity was further enhanced to (7 219±489) U/mL by co-expressing the endogenous protein Kex2. Moreover, the activity that the mutant strain with N-terminal fusion of three amino acids of WLR was increased to (15 145±920) U/mL with a high specific activity of (1 174 600±53 100) U/mg. The efficient secretory expression of enterokinase laid a foundation for its applications in near future.

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Heparin and heparan sulfate are a class of glycosaminoglycans for clinical anticoagulation. Heparosan N-sulfate-glucuronate 5-epimerase (C5, EC 5.1.3.17) is a critical modifying enzyme in the synthesis of heparin and heparan sulfate, and catalyzes the inversion of carboxyl group at position 5 on D-glucuronic acid (D-GlcA) of N-sulfoheparosan to form L-iduronic acid (L-IdoA). In this study, the heparin C5 epimerase gene Glce from zebrafish was expressed and molecularly modified in Escherichia coli. After comparing three expression vectors of pET-20b (+), pET-28a (+) and pCold Ⅲ, C5 activity reached the highest ((1 873.61±5.42) U/L) with the vector pCold Ⅲ. Then we fused the solution-promoting label SET2 at the N-terminal for increasing the soluble expression of C5. As a result, the soluble protein expression was increased by 50% compared with the control, and the enzyme activity reached (2 409±6.43) U/L. Based on this, site-directed mutations near the substrate binding pocket were performed through rational design, the optimal mutant (V153R) enzyme activity and specific enzyme activity were (5 804±5.63) U/L and (145.1±2.33) U/mg, respectively 2.41-fold and 2.28-fold of the original enzyme. Modification and expression optimization of heparin C5 epimerase has laid the foundation for heparin enzymatic catalytic biosynthesis.

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Herein, we report a straightforward, environmentally friendly, and controllable palladium/ligand catalytic system to enable reductive/oxidative Heck reactions of cyclic enones with thiophene or furan derivatives via C-H activation. The key to this tunable reaction is the appropriate intercepting thienyl-Pd(II)-enolate during the enolization process. Such a controllable and economic protocol would not only provide efficient methods to construct various value-added ß-heteroarylated cyclic ketones/enones but also shed light on developing other conjugate addition reactions via C-H activation.

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Objective To study the protein binding rates ofgardenioside,paeoniflorin and naringin in Weiyanling granules in bovine serum albumin,rat plasma and human plasma.Methods The equilibrium dialysis method was carried to determine the binding-rates of three components in Weiyanling granules in bovine serum albumin,rat plasma and human plasma.The HPLC method was used to determine the mass concentration of three components in weiyanling granules in inner and outer dialysis and to calculate the plasma protein-binding rates.Results The linear relationship,precision,extraction recovery and stability of gardenoside,paeoniflorin and naringin all conformed to the methodological requirements.Within the low,middle and high concentration (5.084,10.04 and 20.08 g/L) of Weiyanling granules,the protein-binding rates of gardenioside and bovine serum albumin were 23.77％ ± 13.39％,10.75％ ± 1.34％,5.82％ ± 6.53％,respectively;the protein-binding rates of paeoniflorin were 51.81％ ± 6.53％,30.12％ ± 6.61％,21.39％ ± 9.45％,respectively;the protein-binding rates of naringin were 70.21％ ± 3.31％,67.61％ ± 1.31％,56.00％ ± 3.46％,respectively;the protein-binding rates of gardenioside and rat plasma were 71.56％ ± 3.00 ％,43.56％ ± 12.22％,40.63％ ± 4.73％,respectively;the protein-binding rates ofpaeoniflorin and rat plasma were 55.72％ ± 1.60％,47.59％ ± 6.33％,40.07％ ± 0.72％,respectively;the protein-binding rates of naringin and rat plasma were 85.85％ ± 3.53％,85.38％ ± 0.99％,79.99％ ± 2.57％,respectively;the protein-binding rates of gardenioside and human plasma were 13.56％ ± 2.40％,3.02％ ± 2.41％,5.82％ ± 2.08％,respectively;the protein-binding rates of paeoniflorin and human plasma were 9.49％ ± 5.23％,5.01％ ± 1.10％,3.98％ ± 1.54％,respectively;the protein-binding rates of naringin and human plasma were 25.04％ ± 2.61％,26.09％ ± 13.82％,20.20％ ± 2.24％,respectively.Conclusions Within 5.084,10.04 and 20.08 g/L,the protein binding-rate of gardenioside,paeoniflorin and naringin were shown asfollow,rat plasma ＞bovine serum albumin ＞ human plasma.There were significant differences in species.

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Hyaluronic acid (HA) is widely used in many fields, such as medicine, cosmetics and food. The bioactivity of HA depends on its molecular weight (Mw). Owing to the important physiological activities and special physiological functions, HA oligosaccharides have important application prospects in medicine fields. Streptococcus zooepidemicus has wide applications in commercial production of HA, due to its short fermentation cycle and strong production intensity. In order to efficiently synthesize HA oligosaccharides and solve the dissolved oxygen in the fermentation process, in this study, we overexpressed HA synthase (HasA) and introduced and optimized the leech hyaluronidase LHAase in Streptococcus zooepidemicus WSH-24. As a result, HA oligosaccharides were efficiently produced with improved dissolved oxygen. After 24 h, HA oligosaccharides production intensity reached to 294.2 mg/(L·h), and the concentration accumulated to 0.97 g/L in flask cultures, which was 1.82 times of the wild strain. Impressively, HA oligosaccharides were increased to 7.06 g/L in 3 L fermentor. The constructed Streptococcus zooepidemicus strain for producing HA oligosaccharides would have broad application prospects.

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Ethyl carbamate (EC), a carcinogenic and teratogenic chemical that is widely distributed in various alcoholic beverages, has attracted much attention. Microbial enzymatic degradation of EC in rice wine is always efficient and attractive. In this review, we summarize the research progress and problems of microbial enzymatic elimination of EC in rice wine from three aspects: the mechanisms of EC formation in rice wine, the research progress of acid urease, and the research progress of urethanase. Then, we propose the corresponding strategies to solve the problems: screening new urethanase with satisfied enzyme properties, food-grade expression and directed evolution of the bifunctional Fe³⁺-dependent acid urease and acid urease used in combination with urethanase to eliminate both urea and EC in rice wine.

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