Construction of Raji-Luc CD19 KO Lymphoma Cell Line Using CRISPR/Cas9 Technology / 现代检验医学杂志

Objective To construct Raji-Luc lymphoma cells with CD19 knockout using CRISPR/Cas9 technology and preliminarily validate their immune escape ability.Methods PB-CRISPR-CD19 small guide RNA(sgRNA)plasmids was constructed,the optimal sgRNA sequence was screened,and Raji-Luc cells with pCAG-PBase,PB-CD19 sgRNA,and PB-CRISPR-Cas9 were co-transfected.Stable knockout monoclonal cell lines were screened by flow sorting and limit dilution method and the knockout effect was verified through gene sequence testing.The expression of luciferase on the surface of the cell line was detected by microplate reader,CD19 CAR-T and CD38 CAR-T previously constructed in the laboratory were used as effector cells,and the immune escape ability of Raji-Luc CD19 KO cell line was verified by universal luciferase chemiluminescence method.Results The transfection efficiency of Raji-Luc CD19 KO cells prepared by electro transfection was high,and the knockout efficiency of the two monoclonal cells was more than 99%.There was no significant difference in luciferase expression compared to the original Raji-Luc cells,and CD19 CAR-T cells could not be activated to the kill them.Conclusion Successfully constructed Raji-Luc CD19 KO lymphoma cell line.

An ultrapotent RBD-targeted biparatopic nanobody neutralizes broad SARS-CoV-2 variants

The wide transmission and host adaptation of SARS-CoV-2 have led to the rapid accumulation of mutations, posing significant challenges to the effectiveness of vaccines and therapeutic antibodies. Although several neutralizing antibodies were authorized for emergency clinical use, convalescent patients derived natural antibodies are vulnerable to SARS-CoV-2 Spike mutation. Here, we describe the screen of a panel of SARS-CoV-2 receptor-binding domain (RBD) targeted nanobodies (Nbs) from a synthetic library and the design of a biparatopic Nb, named Nb1-Nb2, with tight affinity and super wide neutralization breadth against multiple SARS-CoV-2 variants of concern. Deep-mutational scanning experiments identify the potential binding epitopes of the Nbs on the RBD and demonstrate that biparatopic Nb1-Nb2 has a strong escape resistant feature against more than 60 tested RBD amino acid substitutions. Using pseudovirion-based and trans-complementation SARS-CoV-2 tools, we determine that the Nb1-Nb2 broadly neutralizes multiple SARS-CoV-2 variants, including Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2), Lambda (C.37), Kappa (B.1.617.1) and Mu (B.1.621). Furthermore, a heavy chain antibody is constructed by fusing the human IgG1 Fc to Nb1-Nb2 (designated as Nb1-Nb2-Fc) to improve its neutralization potency, yield, stability and potential half-life extension. For the new Omicron variant (B.1.1.529) that harbors unprecedented multiple RBD mutations, Nb1-Nb2-Fc keeps a firm affinity (KD < 1.0x10-12 M) and strong neutralizing activity (IC50 = 0.0017 nM). Together, we developed a tetravalent biparatopic human heavy chain antibody with ultrapotent and broad-spectrum SARS-CoV-2 neutralization activity which highlights the potential clinical applications.

Relationship between different obesity phenotypes and abnormal blood pressure in children and adolescents in Yinchuan city / 中华实用儿科临床杂志

Objective:To investigate the relationship between different obesity phenotypes and abnormal blood pressure in children and adolescents in Yinchuan city, and to provide appropriate treatment and intervention measures for obese children and adolescents.Methods:The current research design was adopted to facilitate the cluster sampling.A total of 1 047 children and adolescents aged 12 to 18 in Yinchuan were enrolled in this study from September 2017 to September 2018.There were 530 males and 517 females, with an average age of (13.93±1.24) years old.The questionnaire survey, physical examination and laboratory testing were carried out.Statistical analysis was performed by using SPSS 19.0 software.Results:Among the children and adolescents with normal weight, the composition ratio of the metabolically unhealthy normal-weight (MUNW) phenotype was 7.6%.In the obese cases, the composition ratio of the metabolically healthy obesity (MHO) phenotype was 20.2%.The blood pressure of MUNW [systolic pressure SBP: (119±13) mmHg(1 mmHg=0.133 kPa); diastolic pressure(DBP)(74±10) mmHg] and metabolically unhealthy obesity (MUO) [SBP (127±10) mmHg; DBP(74±7) mmHg] phenotypes were significantly higher than those of the metabolically healthy normal-weight (MHNW) phenotype (all P<0.05). The blood pressure of the MUO [SBP(127±10) mmHg; DBP(74±7) mmHg] phenotype was significantly higher than that of the MHO phenotype ( P<0.05). After adjusting for age, gender, and family history of hypertension, MUNW and MUO phenotypes were 5.93 (95% CI: 3.10-11.36) and 11.63 (95% CI: 6.37-21.24) times more likely to develop blood pressure abnormalities than MHNW phenotypes, respectively ( P<0.001). The MHO phenotype was 0.63 (95% CI: 0.08-4.93) times more likely to develop blood pressure abnormalities than the MHNW phenotype ( P=0.66). Conclusions:The MHO phenotype does not increase the risk of abnormal blood pressure, while the MUNW phenotype does.Therefore, it is recommended to identify the MHO phenotype and MUNW phenotype in order to provide appropriate obesity treatment and interventions for children and adolescents.

Serological screening and analysis of clinical characteristics for celiac disease in susceptible population in Southern China / 中华内科杂志

Objective:To determine the seroprevalence of celiac disease in susceptible population, and to analyze the relationship between demographic characteristics, dietary habits, lifestyle and serological positivity so as to provide guidance for the prevention and treatment of celiac disease in Southern China.Methods:A total of 1 273 individuals who participated in Guangdong Province Health Screening Program in 2015, were selected as serologically positive subjects of celiac disease, including people with irritable bowel syndrome, colitis, diarrhea, anemia, low BMI, short stature, type 1 diabetes mellitus (T1DM), rheumatoid arthritis (RA), ankylosing spondylitis, psoriasis and bristol grade=6 or 7. All subjects were tested for serum IgA anti-tissue transglutaminase antibodies (TTGA), IgA antibodies against deamidated gliadin peptides(DGPA) and IgG against deamidated gliadin peptides (DGPG). Dietary habits, lifestyle and demographic characteristics were compared in subgroups.Results:The seroprevalence of celiac disease in susceptible population was 0.94% (95% CI 0.54%-1.64%) including 0.08% (1/1 273) for TTGA, 0.47% (6/1 273) for DGPA, and 0.39% (5/1 273) for DGPG. The seropositive rate was 3.6% (1/28) in patients with psoriasis, 2.1% (2/95) in the low BMI group, 1.9% (1/53) in T1DM group, 1.8% (3/169) in diarrhea group and 1.1% (5/463) in RA group. No significant difference was found in age, gender, high carbohydrate diet or lifestyle between the negative and the positive subjects. Conclusions:In Southern China, the seropositive rate of celiac disease is 0.94% in susceptible population, which prompts an urgent need of serological screening for early diagnosis.

A Fluorescence Resonance Energy Transfer Biosensor Based on Graphene Quantum Dots and Protoporphyrin IX for the Detection of Melamine.

Graphene quantum dots (GQDs), which have high photostability, anti-photobleaching and scintillation, good biocompatibility and low toxicity, are important member of the fluorescent material family, and have attracted extensive research interest. In this paper, a fluorescence resonance energy transfer (FRET) biosensor based on protoporphyrin IX (PpIX) and GQDs was developed for melamine detection. PpIX was bound to the surface of GQDs to produce self-assembled nanosensors, and a FRET process occurred between GQDs and PpIX. However, due to the combination of melamine and PpIX, the FRET process was shut down in the presence of melamine. The FRET system could quickly and accurately detect melamine with a detection range of 1.0 × 10-8 to 2.0 × 10-6 mol/L based on the fluorescence intensity ratio of PpIX and GQDs, and the detection limit was 3.6 × 10-9 mol/L. This method obtained satisfactory results when it was employed to the determination of melamine in milk samples.

Humanized Single Domain Antibodies Neutralize SARS-CoV-2 by Targeting Spike Receptor Binding Domain

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread across more than 200 countries and regions, leading to an unprecedented medical burden and live lost. SARS-CoV-2 specific antivirals or prophylactic vaccines are not available. Neutralizing antibodies provide efficient blockade for viral infection and are a promising category of biological therapies. Using SARS-CoV-2 spike RBD as a bait, we have discovered a panel of humanized single domain antibodies (sdAbs). These sdAbs revealed binding kinetics with the equilibrium dissociation constant (KD) of 0.7~33 nM. The monomeric sdAbs showed half maximal inhibitory concentration (IC50) of 0.003~0.3 g/mL in pseudotyped particle neutralization assay, and 0.23~0.50 g/mL in authentic SARS-CoV-2 neutralization assay. Competitive ligand-binding data suggested that the sdAbs either completely blocked or significantly inhibited the association between SARS-CoV-2 RBD and viral entry receptor ACE2. Finally, we showed that fusion of the human IgG1 Fc to sdAbs improved their neutralization activity by tens of times. These results reveal the novel SARS-CoV-2 RBD targeting sdAbs and pave a road for antibody drug development.

Application of maleimide modified graphene quantum dots and porphyrin fluorescence resonance energy transfer in the design of ''turn-on'' fluorescence sensors for biothiols.

Two novel fluorescent probes were designed to detect the biothiol in foods using the highly efficient Michael addition reaction between maleimide-derived probes and the biothiol. First, maleimide functionalized GQDs (M-GQDs) were synthesized and used for biothiol identification according to the Michael addition principle. The biothiol can be detected in the range of 5 × 10-9 to 4 × 10-7 mol/L and the detection limit was 1.69 × 10-9 mol/L. Then, a fluorescence resonance energy transfer (FRET) system between M-GQDs and tetrakis (4-aminophenyl) porphyrin (TAPP) for biothiol detection was developed. However, the process of FRET was switched off in the presence of biothiols due to the switch of M-GQDs fluorescence emission to the"ON" mode following the Michael addition mechanism. The system could quickly and accurately detect the biothiol with a detection range of 6.7 × 10-10 to 2 × 10-7 mol/L and a detection limit of 2.34 × 10-10 mol/L. Compared to the single detection system, the FRET system had a wider detection range and lower detection limit, and the related biomolecules did not interfere with the quantitative identification of the biothiol. The proposed method was successfully applied for the determination of the biothiol in foods and human blood samples.

Research progresses of echocardiography in evaluation of right heart structure and function in heart failure with preserved ejection fraction patients / 中国医学影像技术

The incidence and mortality of heart failure with preserved ejection fraction (HFpEF) are increasing year by year. Right ventricle dysfunction (RVD) is an independent predictor of poor prognosis of HFpEF patients. Early evaluation of right heart structures and degrees of RVD are of great significance to the treatment and prognosis of HFpEF patients. The progresses of echocardiography in evaluation of the right heart structure and function in HFpEF were reviewed in this article.

Assessment of right ventricular function by two-dimensional speckle tracking echocardiography in heart failure patients with different left ventricular diastolic dysfunction grade / 中华超声影像学杂志

Objective:To evaluate the right ventricular(RV) function by two-dimensional speckle tracking echocardiography(2D-STE) in heart failure patients with different left ventricle diastolic dysfunction grade.Methods:Twenty-nine healthy volunteers(control group), sixteen heart failure patients with reduced ejection fraction(HFrEF group) and eighty-six heart failure patients with preserved ejection fraction(HFpEF group) were enrolled in the Second Affiliated Hospital of Chongqing Medical University from October 2018 to September 2019. HFpEF patients were further divided into four subgroups according to recommendations of the American Society of Echocardiography in 2016: normal left ventricular diastolic function group and left ventricular diastolic dysfunction groups with grade 1, 2, 3 (LVDD1, LVDD2, LVDD3). Conventional ultrasonic parameters were obtained in apical four-chamber images, including RV basal diameter(RVD1), RV middle diameter(RVD2) and RV longitudinal diameter(RVD3), RV end diastolic area(EDA), end systolic area(ESA) and fractional area change(FAC), peak systolic velocity(S′), myocardial performance index(MPI), tricuspid annular plane systolic excursion(TAPSE). 2D-STE was performed to observe strain parameters, including basal, middle, apical and the whole longitudinal peak systolic strain of RV free wall respectively (RVLSbas, RVLSmid, RVLSapi and RVLSfw). Then 2D strain parameters were compared among these groups, and the correlation between 2D strain parameters and conventional ultrasonic parameters were analyzed.Results:①TAPSE and S′ gradually decreased in normal group, HFpEF group and HFrEF group(all P<0.05). For the four subgroups of HFpEF, compared to LVDD3, TAPSE、S′ increased significantly in normal group, LVDD1 and LVDD2(all P<0.05). ②RVLSbas, RVLSmid, RVLSfw gradually increased in control group, HFpEF group and HFrEF group(all P<0.05). The same trend appeared in group LVDD1, LVDD2 and LVDD3(all P<0.05). ③In control group, HFpEF group and HFrEF group, RVLSfw showed strong correlation with LVEF( r=0.77, P<0.01) and middle correlation with age, TAPSE, and S′( r=0.41, -0.48, -0.40, P<0.01). In the subgroups of HFpEF, RVLSfw had middle correlation with LV diastolic function( r=0.59, P<0.01), and weak correlation with age( r=0.21, P<0.01), and the same correlations with B-type natriuretic peptide(BNP), FAC, TAPSE( r=0.28, -0.29, -0.29; all P<0.01). Conclusions:2D-STE can detect the early subtle impairment of RV systolic function in HFpEF patients.

Association between leptin and postpartum depression / 中国神经精神疾病杂志

Objective This study aims to examine the association between leptin and postpartum depression symptoms. Methods Two hundred pregnant women were enrolled and their prenatal serum leptin levels were measured by using enzyme-linked immunosorbent assay (ELISA). The state of depression was first assessed on the third day after delivery and reassessed by a telephone follow up on the 42nd day using the Edinburg postnatal depression scale (EPDS) after delivery. Patients with postpartum depression symptoms with EPDS score ≥13 points after 3 days postpartum or 42 days postpartum were recruited as the depressive symptom group. Results The medians and lower and upper quartiles of the prenatal serum leptin levels in the depressive symptom group (the 3rd day) and the control group were 1.36 (1.15, 1.68) μg/L and 1.49 (1.28, 1.91) μg/L, respectively. After normal conversion, the serum leptin level was significantly lower in the depressive symptom group than in the control group (P=0.021). The medians and lower and upper quartiles of the prenatal serum leptin levels in the depressive symptom group (the 42nd day) and the control group were 1.17 (1.01, 1.36) μg/L and 1.50 (1.29, 1.90) μg/L, respectively. After normal conversion, the serum leptin level was significantly lower in the depressive symptom group than in the control group (P＜0.001). EPDS scores 3 days postpartum (r=-0.199, P=0.014) and 42 days postpartum (r=-0.254, P=0.002) were negatively correlated with prenatal serum leptin levels. Multiple logistic regression analysis showed that the prenatal leptin levels were associated with depressive symptoms at 42 days postpartum (OR=0.026, P=0.001). Conclusion Prenatal serum leptin levels may be associated with postpartum depressive symptoms, and high levels of leptin are protective factors for postpartum depression.

Effectiveness of rapid hepatitis B vaccination with different vaccine dosages and types in adults / 中华流行病学杂志

Objective To evaluate the effectiveness of rapid hepatitis B vaccination with different vaccine dosages and types in adults.Methods Adults who were aged ≥20 years,negative in the detections of 5 HBV serum markers or only anti-HBc positive were selected from Chaoyang district of Beijing.They were divided into 4 community-based specific groups and given three doses of 10 μ g HepB-SCY vaccine,20 μ g HepB-SCY vaccine,20 μ g HepB-CHO vaccine and 10 μ g HepB-HPY vaccine respectively at month 0,1,and 2.Their blood samples were collected within 1-2 months after completing the three dose vaccination to test anti-HBs level by using chemiluminesent microparticle immunoassay.A face to face questionnaire survey was conducted,and x2 test,Mantel-Haensel x2 test,Kruskal-Wallis rank test and multiple logistic regression analysis were performed.Results A total of 1 772 participants completed vaccination and observation.Their average age was 48.5 years,and 62.75％ of them were females.The anti-HBs positive rates in the groups of 10 μg HepB-SCY,20 μg HepB-SCY,20 μg HepB-CHO and 10 μg HepB-HPY vaccines were 79.49％,84.34％,82.50％ and 74.15％,respectively (P=0.005),and the geometric mean titers (GMT) were 39.53 mIU/ml,62.37 mIU/ml,48.18 mIU/ml and 33.64 mIU/ml respectively (P=0.025).The overall anti-HBs positive rate and GMT were 79.01％ and 41.18 mIU/ml.The anti-HBs GMT of 4 groups declined with age.The differences in anti-HBs GMT among 4 groups minimized with age.The result of logistic modeling indicated that vaccine type and dosage,age and smoking were associated with anti-HBs statistically after controlling the variables of "only anti-HBc positive or not" and "history of hepatitis B vaccination".Conclusion Hepatitis B vaccination at dosage of 20 tg based on 0-1-2 month rapid schedule could achieved anti-HBs positive rates ＞80％ in middle aged and old people,which can be used as supplement of 0-1-6 month routine schedule.

Effectiveness of rapid hepatitis B vaccination with different vaccine dosages and types in adults / 中华流行病学杂志

Objective To evaluate the effectiveness of rapid hepatitis B vaccination with different vaccine dosages and types in adults.Methods Adults who were aged ≥20 years,negative in the detections of 5 HBV serum markers or only anti-HBc positive were selected from Chaoyang district of Beijing.They were divided into 4 community-based specific groups and given three doses of 10 μ g HepB-SCY vaccine,20 μ g HepB-SCY vaccine,20 μ g HepB-CHO vaccine and 10 μ g HepB-HPY vaccine respectively at month 0,1,and 2.Their blood samples were collected within 1-2 months after completing the three dose vaccination to test anti-HBs level by using chemiluminesent microparticle immunoassay.A face to face questionnaire survey was conducted,and x2 test,Mantel-Haensel x2 test,Kruskal-Wallis rank test and multiple logistic regression analysis were performed.Results A total of 1 772 participants completed vaccination and observation.Their average age was 48.5 years,and 62.75％ of them were females.The anti-HBs positive rates in the groups of 10 μg HepB-SCY,20 μg HepB-SCY,20 μg HepB-CHO and 10 μg HepB-HPY vaccines were 79.49％,84.34％,82.50％ and 74.15％,respectively (P=0.005),and the geometric mean titers (GMT) were 39.53 mIU/ml,62.37 mIU/ml,48.18 mIU/ml and 33.64 mIU/ml respectively (P=0.025).The overall anti-HBs positive rate and GMT were 79.01％ and 41.18 mIU/ml.The anti-HBs GMT of 4 groups declined with age.The differences in anti-HBs GMT among 4 groups minimized with age.The result of logistic modeling indicated that vaccine type and dosage,age and smoking were associated with anti-HBs statistically after controlling the variables of "only anti-HBc positive or not" and "history of hepatitis B vaccination".Conclusion Hepatitis B vaccination at dosage of 20 tg based on 0-1-2 month rapid schedule could achieved anti-HBs positive rates ＞80％ in middle aged and old people,which can be used as supplement of 0-1-6 month routine schedule.

Soyasaponin Bb Protects Rat Hepatocytes from Alcohol-Induced Oxidative Stress by Inducing Heme Oxygenase-1.

BACKGROUND: It has been known that oxidative stress induced by alcohol played a crucial role in the formation of alcoholic liver disease. Although the formation mechanisms underlying liver injury induced by alcohol still remained largely unknown, it has been considered that oxidative stress played a core role in the pathogenesis of hepatocyte damage. OBJECTIVE: The aim of this study was to investigate the effects of soyasaponin Bb (Ss-Bb) on oxidative stress in alcohol-induced rat hepatocyte injury. RESULTS: It has been shown that the administration of Ss-Bb could significantly restore antioxidant activity in BRL 3A cells. Moreover, the impaired liver function and morphology changes resulting from ethanol exposure were improved by Ss-Bb treatment. Treatment with a pharmacological inhibitor of haem oxygenase-1 (HO-1) indicated a critical role of HO-1 in mediating the protective role. Finally, we found that pretreatment with Ss-Bb to ethanol exposure cells increased the expression level of HO-1. CONCLUSION: It was suggested that Ss-Bb may protect against alcohol-induced hepatocyte injury through ameliorating oxidative stress, and the induction of HO-1 was an important protective mechanism. SUMMARY: Effects of soyasaponin Bb was investigated on oxidative stress in rat hepatocytesCell viability and antioxidant capacities were evaluated to determine the effectsThe expression level of HO-1 was measured to reveal the proptective mechanisms.

Sensitive fluorescence assay of organophosphorus pesticides based on the fluorescence resonance energy transfer between CdTe quantum dots and porphyrin.

A sensitive and selective quantum dot (QD)-based fluorescence resonance energy transfer (FRET) biosensor was successfully fabricated for the detection of organophosphorus pesticides (OPs). 5,10,15,20-Tetra(4-pyridyl)porphyrin (TPyP) with meso-pyridyl substituents was bound to the surface of CdTe QDs to produce self-assembled nanosensors, and the process of FRET between QDs and TPyP occurred. However, the process of FRET was switched off with the addition of OPs, due to the combination between TPyP and OPs. The fluorescence intensity of TPyP (donor) would decrease gradually with the increasing concentration of OPs. Under optimal conditions, a linear correlation was established between the fluorescence intensity ratio ITPyP/IQDs and the concentration of paraoxon in the range of 9.09 × 10(-12)-1.09 × 10(-6) mol L(-1) with a detection limit of 3.15 × 10(-12) mol L(-1). The attractive sensitivity was obtained due to the efficient FRET and the superior fluorescence properties of QDs. The proposed method was successfully applied to the determination of the OPs in real fruit samples with satisfactory results.

Highly-sensitive organophosphorus pesticide biosensors based on CdTe quantum dots and bi-enzyme immobilized eggshell membranes.

An optical biosensing method using CdTe quantum dots (QDs) and bi-enzyme-immobilized eggshell membranes for the determination of organophosphorus pesticides (OPs) has been developed. Increasing amounts of OPs led to a decrease of the enzymatic activity and thus a decrease in the production of hydrogen peroxide (H2O2), which can quench the fluorescence of the CdTe QDs. Under the optimum conditions, there was a good linear relationship between the enzyme inhibition percentage and the logarithm of paraoxon or parathion concentration in the range of 1.0 × 10(-11)-1.0 × 10(-6) mol L(-1). The detection limit (S/N = 3) of the proposed biosensors were as low as 4.30 × 10(-12) mol L(-1) for paraoxon and 2.47 × 10(-12) mol L(-1) for parathion. The bi-enzyme-immobilized eggshell membrane demonstrated a long shelf-life of at least 2 months and the results showed good repeatability. The proposed method was successfully applied to the determination of the OPs in real fruit samples with satisfactory results.

Optimization of Producing Area and Parts of Gardenia Roots / 中国中医药信息杂志

Objective To optimize the producing area and parts of Gardenia roots. Methods Oleanolic acid 3-acetate was hydrolysed into Oleanolic acid in Gardenia roots from 10 different origins, and root, stem, leaf of Gardenia from Liuyang Hunan, and the content was determined by HPLC. Results The content of oleanolic acid 3-acetate in Gardenia roots of different origins from high to low was:Shaodong, Liuyang of Hunan>Anji of Zhejiang, Guiyang of Hunan>Ningxiang, Anhua of Hunan, Zhangshu of Jiangxi>Liling, Pinjiang, Youxian of Hunan. The content in root was 2 times of that in stem and leaf. Conclusion Experimental data were provided for the optimization of producing area and part of Gardenia roots.

Genotyping and resistant mutants analysis of P gene in HBV fragment sequencing / 中华检验医学杂志

Objective To establish a method for efficient,accurate genotyping and nucleoside drug-resistant mutation analysis for hepatitis B virus ( HBV ).Methods The 48 HBV serum samples were collected from the Third People's Hospital of Taiyuan from July to August 2011,and HBV DNA were extracted using the commercial kit.The HBV whole genome and P gene were amplified and sequenced.Each HBV sample was genotyped by both constructing phylogenetic trees and genotyping software analysis.The results from two strategies were compared for every sample.Results A total of 48 HBV full genome sequences were identified into 12 B and 36 C genotype's by both constructing phylogenetic trees and genotyping software analysis,which was exactly the same as the analysis using P gene fragment sequencing.Seven forms of nucleoside drug-resistant mutation were found in the P gene for all the samples,with the ratio of 27.1％ ( 13/48 ),in which all the mutation forms were associated with lamivudine or adefovir,and no other nucleotide drugs-related resistance mutations existed.In addition,there were 11 B and 35 C genotype and 2 B/C hybrid type with the analysis using Real-time PCR genotyping for the 48 samples.Conclusion P gene sequencing can be used as a new clinical method for efficient,accurate HBV genotyping and resistant mutation analysis,which provides guidance for hepatitis B treatment.

Improvement of thermal adaptability and fermentation of industrial ethanologenic yeast by genomic DNA mutagenesis-based genetic recombination / 生物工程学报

Ethanol is an attractive alternative to fossil fuels. Saccharomyces cerevisiae is the most important ethanol producer. However, in the process of industrial production of ethanol, both cell growth and fermentation of ethanologenic S. cerevisiae are dramatically affected by environmental stresses, such as thermal stress. In this study, we improved both the thermotolerance and fermentation performance of industrial ethanologenic S. cerevisiae by combined usage of chemical mutagenesis and genomic DNA mutagenesis-based genetic recombination method. The recombinant S. cerevisiae strain T44-2 could grow at 44 degrees C, 3 degrees C higher than that of the original strain CE6. The survival rate of T44-2 was 1.84 and 1.87-fold of that of CE6 when heat shock at 48 degrees C and 52 degrees C for 1 h respectively. At temperature higher than 37 degrees C, recombinant strain T44-2 always gave higher cell growth and ethanol production than those of strain CE6. Meanwhile, from 30 degrees C to 40 degrees C, recombinant strain T44-2 produces 91.2-83.8 g/L of ethanol from 200 g/L of glucose, which indicated that the recombinant strain T44-2 had both thermotolerance and broad thermal adaptability. The work offers a novel method, called genomic DNA mutagenesis-based genetic recombination, to improve the physiological functions of S. cerevisiae.

Neuronal damage and neurite change in cell model of intractable epilepsy / 中华神经科杂志

Objective To establish the cell model of intractable epilepsy and to observe its neuronal damage and morphologic change of neurites.Methods The model was established by exposing hippocampal neurons to Mg2+ -free media for 3 hours on days 10 of culture.Expression of lactic acid dehydrogenase (LDH) in supernatant was measured as an index of neuronal damage.The morphologic change of neurons and neurites was observed by optical microscope and scanning electron microscope (SEM).Results Compared to the control group, level of LDH (U/L) was significantly increased in the model group at different time points (3 hours: 4.26 ± 1.28, 6 hours: 6.56 ±2.34 and 24 hours: 16.67 ±3.57, P <0.05).With time prolonging, release of LDH in the model group was gradually increased (F = 39.316,P <0.05).Under optical microscope, neurons of model group migrated closely to each other and neurite connections appeared to be gradually "reticulated" after Mg2+ -free media treatment for 24 hours; and the "reticulated" neurites connections become more obvious after 72 hours.Under SEM, neuronal membrane was rough and had several small depressions, neurites were interlaced in cluster.Conclusions Neuronal damage and morphologic change of neurites are verified in the cell model of intractable epilepsy.

A correlation study about binding nursing and respiratory tract infection among psychotic in-patients / 中国实用护理杂志

8 hours and without and binding nursing in these 3 groups respectively. Observed the condition of respiratory tract infection in 3 groups. Results The incidence rate of respiratory tract infection in binding nursing groups was 50%, which was significant higher than that of in no binding nursing group (P8 hours group was 66.67%, and this rate had an tendency of rising with the time of binding nursing lasting (P