As the chip of synthetic biology, enzymes play a vital role in the bio-manufacturing industry. The development of diverse functional enzymes can provide a rich toolbox for the development of synthetic biology. This article reports the construction of an artificial enzyme with the introduction of a non-natural cofactor. By introducing the 4-dimethylaminopyridine (DMAP) cofactor into the optimal protein skeleton via covalent bonds based on a click-chemistry strategy, we successfully constructed a novel artificial enzyme with the DMAP cofactor as the catalytic center. The artificial enzyme successfully catalyzed an unnatural asymmetric Morita-Baylis- Hillman (MBH) reaction between cycloketenone and p-nitrobenzaldehyde, with a conversion rate of 90% and enantioselectivity (e.e.) of 38%. This study not only provides an effective strategy for the design of new artificial enzymes but also establishes a theoretical basis for the development of unnatural biocatalytic MBH reactions.
Biocatalysis ; 4-Aminopyridine/chemistry* ; Enzymes/metabolism* ; Coenzymes/chemistry* ; Benzaldehydes/chemistry* ; Protein Engineering/methods* ; Click Chemistry

Terpine-4-ol is abundant in nature. As a cyclic monoterpenoid compound， terpine-4-ol is distributed in a variety of natural plants. It is the main component and the key active substance in many traditional Chinese essential oils， such as Melaleuca alba essential oil and coral ginger essential oil. Terpine-4-ol has anti-microbial， anti-tumor， insecticidal， anti-inflammatory， and other effects. It can treat cancer， as well as oral and cardiovascular diseases with great safety. In terms of antibacterial activity， terpine-4-ol can destroy bacterial cell walls， improve membrane permeability， and regulate bacterial migration， reproduction， and other related genes to inhibit bacterial activity. In terms of antifungal activity， terpine-4-ol can bind with ergosterol in fungal cell walls to cause fungal death. In terms of insecticidal activity， terpine-4-ol can inhibit Na⁺ and K⁺-ATPase activity and cause the death of the insect. In terms of anticancer activity， terpine-4-ol can regulate the expression of apoptosis-related proteins in cancer cells， so as to control the apoptosis of cancer cells. In this paper， the pharmacological activity and action mechanism of terpine-4-ol were reviewed to provide a reference for further research and utilization of terpine-4-ol.

Objective:To explore the feasibility of quantitative evaluation of extracellular volume (ECV) fraction in acute ST-segment elevation myocardial infarction (STEMI) by dual-layer spectral detector CT.Methods:The clinical and imaging data of 20 patients with STEMI who underwent cardiac contrast-enhanced CT and MRI from January to October 2019 in Renji Hospital affiliated to Shanghai Jiaotong University School of Medicine were retrospectively analyzed.The dual spectral detector was used in the enhanced CT scan of the coronary artery with retrospectively gate and the late iodine enhancement with prospective gate. Conventional image and holographic spectral image were obtained by iterative and spectral reconstruction. The short axis image of the heart matched with MR image was obtained by multiplanar reconstruction. Based on the data of spectral based image, the IDD map was reconstructed for the calculation of myocardial CT-ECV during the late iodine enhancement. ECV of infarcted myocardium, salvageable myocardium and remote myocardium based on CT and MRI were calculated respectively. Bland-Altman consistency test and intra group correlation coefficient analysis (ICC) were used to compare the consistency of two measurements and different methods. The correlation between CT-ECV and MRI-ECV was compared by Spearman method.Results:The CT-ECV values of infarcted, salvageable, and remote myocardium were 51.21 (49.27, 53)%, 38.64 (36.17, 40)%, and 51.21 (49.27, 53)%, respectively. The difference was statistically significant ( H= 43.17, P<0.01). The CT-ECV value of infarcted myocardium was significantly higher than that of salvageable myocardium and remote myocardium ( Z=-24.60, 35.40, P<0.01), but there was no significant difference between salvageable myocardium and remote myocardium ( Z= 10.80, P=0.15). The T 1 values of infarcted myocardium, salvageable myocardium and remote myocardium were (1 554.85±70.94), (1 443.85±67.28) and (1 307.05±91.73) ms respectively, the difference was statistically significant ( F=51.35, P<0.01). The T 1 value of infarcted myocardium was higher than that of salvageable myocardium and remote myocardium ( t=-5.07, 9.55, P<0.01), and salvageable myocardium was significantly higher than that of remote myocardium ( t=5.38, P<0.01). The MRI-ECV values of infarcted myocardium, salvageable myocardium and remote myocardium were 55.00 (49.27, 57.75)%, 33.50 (29.00, 35.00)%,and 27.00 (26.00, 29.00)%, respectively. The difference was statistically significant ( Z= 47.12, P<0.01). MRI-ECV of infarcted myocardium was significantly higher than that of salvageable myocardium and remote myocardium ( Z=37.45, -20.30, P< 0.01), and salvageable myocardium was significantly higher than that of remote myocardium ( Z = 17.15, P<0.05). The difference between CT-ECV and MRI-ECV measured by two physicians was good. The bias of Bland-Altman analysis was -0.1% (95% CI:-5.5%-5.2%), 0.8% (95% CI:-9.8%-8.2%), and the ICC values were 0.92 and 0.94, respectively. The bias of Bland-Altman analysis in CT-ECV and MRI-ECV consistency test was 4.00% (95% CI:-9.0%-16.9%) and ICC value was 0.88, which had a good correlation ( r=0.75, P=0.001). Conclusions:The iodine density based ECV fromdual-layer spectral detector CT can be used to quantitatively evaluate the changes of extracellular space after acute STEMI, which is helpful to quantitatively evaluate the histological changes after myocardial ischemia.

Objective To compare the efficacy and safety of Iamivudine-interferon sequential therapy and lamivudine monotherapy in HBeAg-positive chronic hepatitis B (CHB) patients.MethodsA total of 172 patients with HBeAg-positive CHB were randomized to sequential group (n=83) or lamivudine group (n=89).Sequential group were administrated with lamivudine 100 mg/d and 5 million units interferon alpha 2b subcutaneous injection every other day for 24 weeks were added since week 25 of treatment.Lamivudine group were administrated with lamivudine 100 mg/d for 48 weeks.All subjects were followed up for 24 weeks after drug withdrawal.Measurement data with homogeneity of variance were analyzed by using t test and data with heterogeneity of variance were analyzed by using rank sum test.The comparison of rates was done by chi square test or Fisher exact test.ResultsThe baseline hepatitis B virus (HBV) DNA levels of patients in sequential group and lamivudine group were (7.8±1.0) and (7.9±1.1) lg copy/mL,respectively (P＞0.05),and the baseline alanine aminotransferase (ALT) levels were (210.5 ± 150.1 ) and (211.9 ± 160.9) U/L,respectively (P＞0.05).At the end of treatment,higher ALT levels [(78.4±146.1) vs (36.1±32.4) U/L,P＜0.05)] and HBV DNA levels [(4.5±1.5) vs (3.8±1.3) lg copy/mL,P＜0.05)] levels,lower response rates (65.8％ vs 83.5％,P＜0.05),and similar HBeAg loss rates (31.6％ vs 22.2％,P＞0.05) and HBeAg seroconversion rates (27.6％ vs 16.0％,P＞0.05) were found in sequential group compared with lamivudine group.At the end of follow-up,higher ALT levels [(126.0±143.1) vs (82.7±83.0) U/L,P＜0.05)],similar HBV DNA levels [(5.3±1.5) vs (5.0±1.5) lg copy/mL,P＞0.05)],similar HBeAg loss rates (25.0％ vs 32.3％,P＞0.05) and HBeAg seroconversion rates (25.0 ％ vs 26.2 ％,P＞0.05) were found in sequential group compared with lamivudine group.YMDD motif mutation rate in sequential group was lower than lamivudine group at week 48 of treatment (10.5％ vs 26.9％,P＜0.05).ConclusionsLamivudine-interferon sequential therapy and lamivudine monotherapy are both effective in HBeAg-positive CHB patients,while HBV mutations are reduced in patients with sequential therapy.

Objectives To investigate the clinical characteristics and the regularity of seasonal changes that influence peptic ulcer (PU) in Nanehang area and to provide a theoretical basis for the treatment and prevention of PU.Methods Data collected from patients with PU diagnosed by clinic and gastroendoseopy between October 2003 to May 2008 were retrospectively analyzed.The PU was further divided into gastric ulcer,duodenal ulcer and complex ulcer.The lesion of gastric ulcer was calculated by five locations that were antral,angular,corporal,pyloric canal,fundic and cardia.The lesion of duodenal ulcer was calculated by five locations that were anterior wall of bulb,posterior wall,lesser curvature, greater curvature and postbulbar.The climate changes that influnced the incidence of PU disease were also observed.The detective rates of different types of PU were analyzed and its association with gender,age, lesion locations,seasons,Helicobacter pylori (Hp) infection and complications were also investigated. Results Among 83 888 patients who underwent endoscopy,PU was found in 21 308 patients (25.4%) including 66.33% duodenal ulcer,24.88% gastric ulcer and 8.79% complex ulcer.The male and femal ratio was 2.44 : 1 in PU,2.53 : 1 in duodenal ulcer,2.26 : 1 in gastric ulcer,and 2.33 : 1 in complex ulcer.The average age of patients with gastric ulcer was 48.0 years that was about 6.7 years higher than that of patients with duodenal ulcer.The prevalence of duodenal ulcer and gastric ulcer peaked in the 30- 39 years and 50-59 years,respectively.PU was more common from December to February (30.17%) and less common from June to August (22.54%) (P＜0.01) .The 57.43% of duodenal ulcer was found on anterior wall of bulb,18.26% on greater curvature,13.21% on lesser curvature,7.34% on posterior wall and 3.76% on postbulbar.The 45.69% of gastric ulcer was found on antral,20.54% on angular, 15.54% on corporal,9.36% on pyloric canal,and 8.87% on fundic and cardia.The 91.83% (12 318/ 13 414) of patients were positive for Hp infection.There was no significant difference of Hp infection among patients with different types of PU.The complications in patients with PU were bleeding (4.94%),pyloric obstruction (3.51%) and chronic perforation(0.04%).Conclusions The detective rate of PU in Nanchang area is 25.4%,which is higher than that in northern area of China.The incidence of PU is highly associated with sex,age,seasons and ulcer locations,with high Hp infections and a low incidence of complications.

Objective To investigate the therapeutic effieacy and safety of 18 α-Diammonium glycyrrhizinate phosphatidylcholine complex (DGPC) in patients with chronic hepatitis B and or C with elevated aminotransferase. Methods 55 patients with chronic hepatitis B and or C, with serum alanine aminotransferase (ALT) of 2 to 10 times the upper limit of normal were randomly assigned to receive DGPC or Diammonium glyeyrrhizinate (DG) for 12 weeks. Then they were followed up for an additional 4 weeks. From week 1 to 10, DGPC or DG was given as 150 nag,three times a day (TID). At the 11th week,the drug was given as 100 mg,TID. Then 50 mg,TID for the 12th week. Results ALT was markedly decreased after receiving DGPC 4,8,12 weeks (P=0.00). ALT normalization rate at the end of therapy was similar (38.5% vs 34.5% ,P =0.76). Drug-related adverse events were similar. Conclusion DGPC can rapidly and safely decrease aminotransferase in patients with chronic viurs hepatitis.

OBJECTIVETo study the quantity of anti-R7V in individuals infected with HIV and AIDS patients and its relation with the progression of disease.

METHODSELISA and precipitation and other methods were used to investigate the quantity of anti-R7V in asymptomatic long-term survivors and AIDS patients.

RESULTSPositive rate and quantity of anti-R7V were higher in the HIV active ones and AIDS. It showed that the quantity and positive rate of anti-R7V were rather high in dissolving test.

CONCLUSIONSIt is strong suggestion for anti-R7V to obstruct the replication of virus by interfering the connection between HIV with CCR5 or CXCR4 and so it impossible HIV entering to CD4+ T cells.

Acquired Immunodeficiency Syndrome ; immunology ; Adolescent ; Adult ; Aged ; Child ; Female ; Follow-Up Studies ; HIV Antibodies ; blood ; HIV Infections ; immunology ; HIV Long-Term Survivors ; HIV-1 ; immunology ; Humans ; Male ; Middle Aged ; Receptors, CCR5 ; physiology ; Receptors, CXCR4 ; physiology