(+)-Borneol, the main component of "Natural Borneol" in the Chinese Pharmacopoeia, is a high-end spice and precious medicine. Plant extraction cannot meet the increasing demand for (+)-borneol, while microbial biosynthesis offers a sustainable supply route. However, its production was extremely low compared with other monoterpenes, even with extensively optimizing the mevalonate pathway. We found that the key challenge is the complex and unusual dephosphorylation reaction of bornyl diphosphate (BPP), which suffers the side-reaction and the competition from the cellular dephosphorylation process, especially lipid metabolism, thus limiting (+)-borneol synthesis. Here, we systematically optimized the dephosphorylation process by identifying, characterizing phosphatases, and balancing cellular dephosphorylation metabolism. For the first time, we identified two endogenous phosphatases and seven heterologous phosphatases, which significantly increased (+)-borneol production by up to 152%. By engineering BPP dephosphorylation and optimizing the MVA pathway, the production of (+)-borneol was increased by 33.8-fold, which enabled the production of 753 mg/L under fed-batch fermentation in shake flasks, so far the highest reported in the literature. This study showed that rewiring dephosphorylation metabolism was essential for high-level production of (+)-borneol in Saccharomyces cerevisiae, and balancing cellular dephosphorylation is also helpful for efficient biosynthesis of other terpenoids since all whose biosynthesis involves the dephosphorylation procedure.

Objective To explore the changes in neural activity in patients with type 2 diabetes mellitus(T2DM)and their corre-lation with executive function,and to analyze the neural mechanisms underlying the decline in executive function in T2DM patients.Methods Thirty-one T2DM patients(T2DM group)and thirty-two healthy controls(HC)(HC group)matched for body mass index(BMI)underwent resting-state functional magnetic resonance imaging(rs-fMRI)scans and N-back task tests were included.Differ-ences in the amplitude of low-frequency fluctuation(ALFF),regional homogeneity(ReHo),and seed-based functional connectivity(FC)between the two groups were compared,and partial correlation analyses were performed between the difference results and N-back task performance.Results The T2DM group showed prolonged reaction time(RT)in the 1-back and 2-back tasks.T2DM patients exhibited increased ALFF in the bilateral caudate nucleus,left medial superior frontal gyrus,and right postcentral gyrus,as well as elevated ReHo in the right putamen.FC analysis revealed significant alterations in FC between the caudate nucleus,putamen,and multiple brain regions in T2DM patients,with some of these FC changes significantly correlated with RT and accuracy(ACC)in the N-back task.Conclusion The decline in executive function in T2DM patients may be associated with abnormal neural activity in brain regions such as the striatum,salience network,and frontoparietal control network.FC further decreases under increased cognitive load.These findings provide evidence for the study of the neural mechanisms of executive function impairment in T2DM patients.

Objective To explore the changes in neural activity in patients with type 2 diabetes mellitus(T2DM)and their corre-lation with executive function,and to analyze the neural mechanisms underlying the decline in executive function in T2DM patients.Methods Thirty-one T2DM patients(T2DM group)and thirty-two healthy controls(HC)(HC group)matched for body mass index(BMI)underwent resting-state functional magnetic resonance imaging(rs-fMRI)scans and N-back task tests were included.Differ-ences in the amplitude of low-frequency fluctuation(ALFF),regional homogeneity(ReHo),and seed-based functional connectivity(FC)between the two groups were compared,and partial correlation analyses were performed between the difference results and N-back task performance.Results The T2DM group showed prolonged reaction time(RT)in the 1-back and 2-back tasks.T2DM patients exhibited increased ALFF in the bilateral caudate nucleus,left medial superior frontal gyrus,and right postcentral gyrus,as well as elevated ReHo in the right putamen.FC analysis revealed significant alterations in FC between the caudate nucleus,putamen,and multiple brain regions in T2DM patients,with some of these FC changes significantly correlated with RT and accuracy(ACC)in the N-back task.Conclusion The decline in executive function in T2DM patients may be associated with abnormal neural activity in brain regions such as the striatum,salience network,and frontoparietal control network.FC further decreases under increased cognitive load.These findings provide evidence for the study of the neural mechanisms of executive function impairment in T2DM patients.

Objective:To describe the detail sampling design,weighting,instruments,filed procedures and quality control methods of the epidemiological survey on dementia among community residents in Tongliao City.Methods:A three-stage disproportionate probability sampling design was used to investigate the inhabitants aged 65 years and over in Tongliao City,Inner Mongolia Autonomous Region.The 10/66 Dementia Research Group(10/66 DRG)assessment instruments were used to diagnose dementia,using computer-assisted personal interview mode in the selected older people.Comprehensive quality control methods were implemented throughout the field-work.Results:A total of 166 villages or communities were sampled from nine counties or districts in Tongliao Cit-y.Totally 4 345 older people were interviewed with 96.2％response rate.By calculating sampling design weights,non-response adjustment weights and post-stratification adjustment weights,these weights were multiplied and per-formed trimming adjustment and standardization adjustment to generate final weights.The 171 interviewers were well-trained and qualified to carry out filed interview.Quality control methods included computer data check,audio record check,and telephone check in order to ensure the quality of the survey.Conclusion:This survey is imple-mented using a rigorous sampling design and timely quality control methods,and uses the 10/66 DRG assessment instruments with satisfactory international validity and reliability as survey instruments,which has international cross-cultural comparability.It provides a valid and feasible methodology of epidemiological survey on dementia for further studies in different regions in China.

Objectve:To observe the change of functional connectivity(FC)characteristic and its correlation with cognitive flexibility in type 2 diabetes mellites(T2DM)patients with cognitive flexibility decreased.Methods:A retro-spective analysis was performed in 24 T2DM patients with cognitive flexibility decreased(T2DM+CD),34 T2DM pa-tients without cognitive flexibility decreased(T2DM-CD)and 31 healthy controls(HC).Wisconsin Card Sorting Test(WCST)and the Stroop Color Word Test(Stroop)were respectively used in three groups of subjects to assess cognitive flexibility and functional magnetic resonance imaging(fMRI)scans was used to assess the FC.The differences of cogni-tive flexibility were found between three groups of subjects.The differences of FC between the bilateral(Left and Right,L.and R.)striatum(ST)and the dorsolateral prefrontal cortex(dlPFC)were found between three groups of subjects.Further analysis was focused on the interactive effect of T2DM and cognitive flexibility on FC changes.Results:Com-pared with T2DM-CD and HC,the number of response administered,errors responses,perseverative response,and time in WCST of T2DM+CD were significantly increased,while the number of correct responses was decreased.In Stroop,the number of correct,word-color contradiction and correct word-color indifference in T2DM+CD were lower than HC.In T2DM+CD,FC between L.ST-L.dlPFC,R.ST-L.dlPFC and R.ST-R.dlPFC were decreased,and decreased FC between R.ST-R.dlPFC was associated with cognitive flexibility scale scores.There existed an interactive effect between T2DM and cognitive flexibility on FC changes.Conclusion:Decreased FC between ST and dlPFC is the neural mechanism of cognitive flexibility impairment in T2DM.

【Objective】 To track and evaluate the clinical diagnostic efficacy of an enzyme linked immunosorbent assay (ELISA) kit for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). 【Methods】 Total antibody (TAb) specific to SARS-CoV-2 in blood donors were determined using ELISA reagent. TAb positive donors were followed up 1 month after blood donation. SARS-CoV-2 specific IgG, IgM and pseudotype lentivirus based neutralization test (ppNAT) were conducted for TAb positive blood donors and follow-up samples. ppNAT and IgG antibodies simultaneously positive in ppNAT positive samples and its follow-up samples was used as the standard for antibodies validation. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy and Youden index of SARS-CoV-2 TAb ELISA were analyzed. 【Results】 Among 16 016 blood donors from January 31 to April 28, 2020, 61 donors were diagnosed as TAb positive, 6 cases were positive for ppNAT, in which 2 were positive for both ppNAT and IgG; 4 of 46 TAb positive follow-up samples were positive for ppNAT, in which 2 were positive for IgG simultaneously. The sensitivity, specificity, PPV, NPV, accuracy, Youden index, false positive rate and false negative rate of SARS-CoV-2 TAb reagent were 100.00%, 99.60%, 3.28%, 100.00%, 99.60%, 99.60%, 0.40% and 0.00%, respectively. 【Conclusion】 SARS-CoV-2 TAb ELISA has high sensitivity and good clinical diagnostic efficacy, but the false positive rate is relatively high in low-risk blood donors. Therefore, ppNAT, IgG and follow-up results should be fully considered in clinical in order to analyze the positive results and determine the infection status more accurately.

Objective To investigate the significance of cellular inhibitor of apoptosis proteins 2 (cIAP2) expression in the patients with hepatitis B and non-hepatitis B related hepatocellular carcinoma (HCC).Methods The medical record data and tissue samples in the patients with HCC resection operation were collected.Expression of cIAP2 in HCC cancer lesion,adjacent tissues and cancer-distant tissues was detected by immunohistochemical staining and Western blotting.Results In the cancer lesion,paracancerous tissues and cancer-distant tissues of the two groups,the cIAP2 expression amount was decreased in turn.But in the non-hepatitis B related HCC group,the cIAP2 expression in the cancer-distant tissues was significantly lower than that in the HCC cancer lesion and paracancerous tissues,while in the hepatitis B related HCC group,the cIAP2 expression amounts had no significant difference between the caner-distant tissues and paracancerous tissues,while lower than that in the cancer lesion.Conclusion cIAP2 is one of important mechanisms causing hepatic B related HCC and can serve as a therapeutic target point for inhibiting HCC development and eliminating hepatitis B virus.

Objective: To improve the traditional preparation procedure of effervescent tablets in order to raise stabilization. Methods: The orthogonal design was used for improvement of process. Results: The optimum procedure condition was A 3B 2C 1. That is adding 7.5% citric acid, 11.25% sodium bicarbonate encapsulated by 5% PEG. Conclusion: The new procedure is superior to the traditional procedure, and it is suitable for the requirement of production on a large scale.