The cis-epoxysuccinate hydrolase (CESH) from Rhizobium strain BK-20 is the key enzyme for L(+)-tartaric acid production. To establish a highly efficient and stable production process, we first optimized the enzyme production from Rhizobium strain BK-20, and then developed an immobilized cell-culture process for sustained production of L(+)-tartaric acid. The enzyme activity of free cells reached (3 498.0 +/- 142.6) U/g, and increased by 643% after optimization. The enzyme activity of immobilized cells reached (2 817.2 +/- 226.7) U/g, under the optimal condition with sodium alginate as carrier, cell concentration at 10% (W/V) and gel concentration at 1.5% (W/V). The immobilized cells preserved high enzyme activity and normal structure after 10 repeated batches. The conversion rate of the substrate was more than 98%, indicating its excellent production stability.
Alginates ; chemistry ; Cells, Immobilized ; Glucuronic Acid ; chemistry ; Hexuronic Acids ; chemistry ; Hydrolases ; metabolism ; Rhizobium ; enzymology ; metabolism ; Tartrates ; metabolism

Objective To investigate the correlation between three gene locus polymorphisms of X-ray repair cross-complementary protein 1 (XRCC1) exon (Arg194Trp, Arg280His and Arg399Gln) and the risk of colorectal cancer (CRC). Methods A case-control study was performed in 250 CRC patients (case group, 128 colon cancer patients and 122 rectal cancer patients) and 213 healthy individuals (control group). The three gene locus polymorphism of XRCC1 was tested by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) method. The genotype distribution and allele frequency of each locus was analyzed with SPSS 10.0 software. Results There was no significant difference in allele frequency of XRCC1 at 194 and 399 loci (P > 0.05). However, the 280 Arg/His allele frequency of XRCC1 was higher in case group than that in control group (OR=1.66,95%CI:1.01~2.73,P=0.047). The 280Arg/His allele frequency was higher in rectal cancer group than that in control group (OR =1.82,95%CI:1.02~3.27). The frequency of 280His allele (Arg280His and His280His) was higher in case group than that in control group (OR=1.85,95%CI:1.06~3.22). However, it was a relative low risk factor of colon cancer and there was no significant difference between colon cancer group and control group (OR=1.85, 95%CI:1.06~3.22). Conclusions There was no correlation between XRCC1 Arg194Trp and Arg399Gln polymorpohisms and the risk of CRC. However, 280Arg/His genotype may increase the risk of CRC, and 280His allele is a risk factor of rectal cancer.

Objective:To analyze the research status and hotspots of patients with heart failure at home and abroad, to provide a reference for the exercise rehabilitation research of heart failure patients in China.Methods:The research references on exercise rehabilitation for heart failure patients were retrieved in Web of Science Core Collection database and CNKI from 2011 to 2020 and were analyzed with the information visual software CiteSpace V 5.6 R5. The analysis included the annual distribution, country or institution distribution, journal distribution, author distribution, institute distribution, high-frequency keywords and forewords.Result:A total of 8 896 articles were included in the analysis, including 1 347 Chinese articles and 7 549 English articles. The number of international publications in exercise rehabilitation for patients with heart failure was much higher than that of domestic publications, and the overall trend was sustained growth. Among them, developed countries led by the United States (accounting for 36.415% of the total number of articles) occupy a leading position in exercise rehabilitation for heart failure patients. Foreign literature research hotspots mainly focus on telerehabilitation. In contrast, domestic literature research hotspots mainly included the effects of exercise rehabilitation on elderly patients with heart failure and the intervention of nursing staff in exercise rehabilitation. At the same time, both domestic and foreign paid attention to the effects of exercise rehabilitation on patients with heart failure such as exercise capacity, cardiac function, quality of life connection with myocardial infarction.Conclusions:The field of exercise rehabilitation for patients with heart failure in China has gradually received attention. However, there is a gap between the research and the international levels, so further research is still needed. Telerehabilitation abroad of patients with heart failure can provide references for the development of domestic research.

Objective:To evaluate and summarize the best evidence of exercise instructions for patients with atrial fibrillation.Methods:A comprehensive search about evidence on exercise rehabilitation in patients with atrial fibrillation was conducted in following databases: Joanna Briggs Institute (JBI) Library, The Agency for Healthcare Research and Quality (AHRQ), National Institute for Health and Clinic Excellence (NICE), Scottish Intercollegiate Guidelines Network (SIGN), Registered Nurses′ Association of Ontario (RNAO), Physiotherapy Evidence Database (PEDro), American College of Physicians (ACP), Cochrane Library, PubMed, Embase, CINAHL, Medlive, China National Knowledge Infrastructure (CNKI), WanFang Database, VIP Database, and China Biology Medicine (CBM). The retrieval period was from the inception of databases to January 2021. Two researchers with evidence-based nursing background assessed the quality of the literature independently and identified the level of evidence.Results:A total of 16 articles were included, including 4 guidelines, 4 systematic reviews, 4 expert consensuses, 4 randomized controlled trials. Combined with professional judgment, 35 pieces of best evidence in 7 aspects were summarized, including exercise benefits, the appropriate crowd, exercise evaluation, exercise mode, exercise intensity, exercise time, exercise supervision and safety.Conclusions:Regular exercise is safe and beneficial for patients with atrial fibrillation. Clinical staff should guide patients to exercise moderately by applying the best evidence with scientific exercise intervention, promoting patients′ physical and mental health.

Objective:To analyze the incidence characteristics of occupational chronic benzene poisoning under two diagnostic criteria.Methods:In March 2020, 126 patients who were divided into the old criteria group (74 cases) and the new criteria group (52 cases) were retrospectively analyzed. These patients were diagnosed with occupational chronic benzene poisoning, and were diagnosed in our hospital during the period of January 2009 to December 2019. The gender composition, age of onset, years of benzene exposure, industry distribution, work type, benzene concentration in working environment and diagnostic grade of the two groups of patients were analyzed and compared. The follow-up of 22 benzene poisoning observation subjects under the old criteria were retrospectively analyzed.Results:There were no statistically significant differences in gender composition, age of onset, years of benzene exposure, industry distribution and work type between the old criteria group and the new criteria group ( P>0.05) . In the old criteria group and the new criteria group, 41.9% (31/74) and 17.3% (9/52) of the patients' workplace benzene concentration exceeded the maximum allowable concentration, respectively. The composition of different benzene concentration in the workplace between the two groups showed statistically significant ( P<0.05) . In the old criteria group, the proportion of mild poisoning (79.7%, 59/74) was the majority, while in the new criteria group, the proportion of moderate and severe poisoning (51.9%, 27/52) were the majority, and there was statistically significance in the composition ratio of diagnostic grade between the two groups ( P<0.05) . Under the old criteria, after folow-up of 22 cases of benzene poisoning observation subjects, we observed that 8 cases (36.4%) progressed to the level of chronic benzene poisoning. Conclusion:The revision of diagnostic criteria for benzene poisoning may affect the composition of diagnosis classification. Based on the rights and interests of workers, formulating more complete diagnostic criteria and system policies will be more conducive to the development of occupational benzene poisoning prevention and control.

Objective:To analyze the incidence characteristics of occupational chronic benzene poisoning under two diagnostic criteria.Methods:In March 2020, 126 patients who were divided into the old criteria group (74 cases) and the new criteria group (52 cases) were retrospectively analyzed. These patients were diagnosed with occupational chronic benzene poisoning, and were diagnosed in our hospital during the period of January 2009 to December 2019. The gender composition, age of onset, years of benzene exposure, industry distribution, work type, benzene concentration in working environment and diagnostic grade of the two groups of patients were analyzed and compared. The follow-up of 22 benzene poisoning observation subjects under the old criteria were retrospectively analyzed.Results:There were no statistically significant differences in gender composition, age of onset, years of benzene exposure, industry distribution and work type between the old criteria group and the new criteria group ( P>0.05) . In the old criteria group and the new criteria group, 41.9% (31/74) and 17.3% (9/52) of the patients' workplace benzene concentration exceeded the maximum allowable concentration, respectively. The composition of different benzene concentration in the workplace between the two groups showed statistically significant ( P<0.05) . In the old criteria group, the proportion of mild poisoning (79.7%, 59/74) was the majority, while in the new criteria group, the proportion of moderate and severe poisoning (51.9%, 27/52) were the majority, and there was statistically significance in the composition ratio of diagnostic grade between the two groups ( P<0.05) . Under the old criteria, after folow-up of 22 cases of benzene poisoning observation subjects, we observed that 8 cases (36.4%) progressed to the level of chronic benzene poisoning. Conclusion:The revision of diagnostic criteria for benzene poisoning may affect the composition of diagnosis classification. Based on the rights and interests of workers, formulating more complete diagnostic criteria and system policies will be more conducive to the development of occupational benzene poisoning prevention and control.

Objective:To explore the current status of radiological protection knowledge, attitude and practice of nurses in Interventional Catheterization Room, and analyze their influencing factors so as to provide a basis for formulating intervention strategies.Methods:This study was a cross-sectional study. From April to May 2021, convenience sampling was adopted to select 240 nurses in Interventional Catheterization Room from 32 hospitals of member units of the China Heart Federation as the research subject. The self-designed General Information Questionnaire and the Radiological Protection Knowledge, Attitude and Practice Scale for Interventional Catheterization Room Nurses were used for investigation. Single factor analysis and multiple linear regression analysis were used to explore the influencing factors of radiological protection knowledge, attitude and practice among nurses of Interventional Catheterization Room. A total of 240 questionnaires were issued, and 220 valid questionnaires were returned with the valid response rate of 91.67%.Results:Among 220 nurses in Interventional Catheterization Room, the scores of radiological protection knowledge, attitude and practice dimensions were (5.92±1.83) , (29.15±1.97) , (43.76±5.73) , respectively. Multiple linear regression analysis showed that gender, hospital grade and training frequency were the influencing factors of radiological protection knowledge of nurses in Interventional Catheterization Room, and the differences were statistically significant ( P<0.05) . The training frequency and the type of radiological protective equipment were the influencing factors of the radiation protection attitude of nurses in Interventional Catheterization Room, and the differences were statistically significant ( P<0.05) . Gender, training frequency, regular monitoring of radiation dosimeters, and types of radiation protective equipment were the influencing factors of radiation protective practice of nurses in Interventional Catheterization Room ( P<0.05) . Conclusions:Interventional Catheterization Room nurses have a low level of radiological protection knowledge, and their attitudes towards radiological protection are relatively positive, but their radiological protection practice is not in place. The radiation protection training of nurses in Interventional Catheterization Room should be optimized, and adequate and high-quality protective equipment should be provided, and gender-specific management should be conducted, personal radiation dose monitoring should be standardized, and the radiation guidance role of Class Ⅲ hospitals should be used to ensure the safety and health of medical and nursing staff.

Objective To observe the effects of Coix seed injection on the cell viability and radiosensitivity of human hepatoma cell line Bel-7402.Methods Bel-7402 cells were irradiated by X-rays,or treated with Coix seed injection,or treated with both of them.The cells proliferation and apoptosis were detected by MTT and by flow cytometry respectively.Cell cloning was used to observe the number of viable cells and to draw the cell survival curve.The mRNA and protein level of Bax,Bcl-2 were detected by RT-PCR and Western blot respectively.Results It was found that the Coix seed injection group (12 μmol/L) and X-ray group (8 Gy) had a significant inhibitory effect on the growth of hepatocellular carcinoma cells (t =17.03,11.26,P ＜ 0.05).And compared with Coix group and irradiation group,the combined treatment group showed higher inhibition rate (t =24.80,20.19,P ＜0.05).The mRNA and protein levels of Bax were gradually elevated (F =437.92,67.91,P ＜ 0.05),while the expressions of Bcl-2 reflected a decreased trend (F =31.18,48.50,P ＜ 0.05).The D0 values of pure irradiation group and combined treatment group were 4.27 and 3.34,respectively,and the sensitization enhancement ratio was 1.27.Conclusions The Coix seed injection inhibit cell growth and induce apoptosis,as well as increase radiative sensitization may via the apoptosis related factors Bax and Bcl-2 in hepatocellular carcinoma.

Purpose To investigate the value of T2WI mild-moderate signal and restricted diffusion in the context of liver imaging reporting and data system (LI-RADS) (2014 edition) in the diagnosis of hepatocellular carcinoma (HCC) with cirrhosis caused by hepatitis B virus.Materials and Methods A total of 77 lesions (LI-RADS 3-5,size of 1.1 cm×0.7 cm-12.7 cm×9.1 cm) of 69 HCC patients in Beijing Friendship Hospital from January 2012 to November 2016 were retrospectively analyzed.All these patients underwent MRI scan and multiphase dynamic enhanced scan.The images were analyzed by two radiologists.If a disagreement occurred,liver accelerated volume acquisition and multiphase dynamic enhanced scan were combined to reach a consensus.The contrast noise ratio (CNR) and apparent diffusion coefficient (ADC) of T2WI and diffusion weighted imaging (DWI) sequences were compared,as well as the identification of the two signs.Results There was no statistically significant difference between T2WI mild-moderate signal and restricted diffusion in the identification of lesions (LI-RADS 3-5) (P＞0.05),while the sensitivity with DWI b=0 (61.0％) was significantly lower than DWI b=600 s/mm2 (70.1％) (P＜0.05).The CNR of all DWI sequences (b=0,600 s/mm2) were larger than those of T2WI (P＜0.01).The ADC of small lesions (diameter ＜2 cm) were larger than those of larger lesions (diameter ＞2 cm) [(1.57+0.37)×10-3 mm2/s vs.(1.37+0.51)×10 3 mm2/s,P＜0.05].Conclusion There is no significant difference in sensitivity of lesions between T2WI mild-moderate signal and restricted diffusion.However,due to different CNRs,DWI with b=600 s/mm2 is more obvious for the lesions,and can be first investigated in practice.

Objective To investigate the effect ofmiR-27a-3p on proliferation,apoptosis and cell cycle of hepatoma cells.Methods A quantitative real-time polymerase chain reaction (qPCR) was used to detect differential expression of miR-27a-3p in normal hepatic epithelial cells (L02) and hepatoma cells (HepG2 and PLC).Cell experiment was divided into four groups:HepG2 overexpression cells,Mi-27a-3p overexpression group (Mi-27a) and negative control group (Mi-Con);PLC knockdown cells,Mi-27a-3p knockdown group (Miinhibitor-27a) and negative control group (Mi-inhibitor-Con).The expression of microRNA-27a-3p in each group after transfection was detected by qPCR analysis.MTT assay was used to detect the cell proliferation.Flow cytometry was used to detect the apoptosis and cell cycle.One-way ANOVA was used for multiple comparisons,and t-test was used to compare two groups.Results qPCR results showed that the expression levels of miR27a-3p in L02,HepG2 and PLC increased sequentially,and the relative expression levels were 1.07 ± 0.04,4.81 ± 0.64 and 11.31 ± 0.92,respectively (P ＜ 0.05).MTT assay showed that the cell viability of HepG2 cells transfected with miR-27a-3p overexpression plasrnid was significantly deereased compared with the negative control group (P ＜ 0.05).The apoptosis assay showed that the apoptosis rate of miR-27a-3p overexpression group was higher than the negative control group (P ＜ 0.05).The cell cycle results showed that the proportion of S phase cells in the miR-27a-3p overexpression cell group was significantly lower than the negative control group (P ＜ 0.05).Furthermore,microRNA-27a-3p knockdown validation in PLC cells showed that MTT,apoptosis and cell cycle tests results were opposite to the results of HepG2 overexpression cells,and the differences were statistically significant (P ＜ 0.05).Conclusion miR-27a-3p can significantly inhibit the proliferation of hepatoma cells,promote cell apoptosis,alter the cell cycle distribution,and may become a potential target in hepatocellular carcinoma therapy.