Diterpenoid ferruginol is a key intermediate in biosynthesis of active ingredients such as tanshinone and carnosic acid.However, the traditional process of obtaining ferruginol from plants is often cumbersome and inefficient. In recent years, the increasingly developing gene editing technology has been gradually applied to the heterologous production of natural products, but the production of ferruginol in microbe is still very low, which has become an obstacle to the efficient biosynthesis of downstream chemicals, such as tanshinone. In this study, miltiradiene was produced by integrating the shortened diterpene synthase fusion protein,and the key genes in the MVA pathway were overexpressed to improve the yield of miltiradiene. Under the shake flask fermentation condition, the yield of miltiradiene reached about(113. 12±17. 4)mg·L~(-1). Subsequently, this study integrated the ferruginol synthase Sm CYP76AH1 and Sm CPR1 to reconstruct the ferruginol pathway and thereby realized the heterologous synthesis of ferruginol in Saccharomyces cerevisiae. The study selected the best ferruginol synthase(Il CYP76AH46) from different plants and optimized the expression of pathway genes through redox partner engineering to increase the yield of ferruginol. By increasing the copy number of diterpene synthase, CYP450, and CPR, the yield of ferruginol reached(370. 39± 21. 65) mg·L~(-1) in the shake flask, which was increased by 21. 57-fold compared with that when the initial ferruginol strain JMLT05 was used. Finally, 1 083. 51 mg·L~(-1) ferruginol was obtained by fed-batch fermentation, which is the highest yield of ferruginol from biosynthesis so far. This study provides not only research ideas for other metabolic engineering but also a platform for the construction of cell factories for downstream products.
Saccharomyces cerevisiae/genetics* ; Diterpenes/metabolism* ; Metabolic Engineering ; Fermentation ; Abietanes

OBJECTIVE: To evaluate the dynamic changes of glucocorticoid (GC) dose and the feasibility of GC discontinuation in rheumatoid arthritis (RA) patients under the background of Chinese medicine (CM). METHODS: This multicenter retrospective cohort study included 1,196 RA patients enrolled in the China Rheumatoid Arthritis Registry of Patients with Chinese Medicine (CERTAIN) from September 1, 2019 to December 4, 2023, who initiated GC therapy. Participants were divided into the Western medicine (WM) and integrative medicine (IM, combination of CM and WM) groups based on medication regimen. Follow-up was performed at least every 3 months to assess dynamic changes in GC dose. Changes in GC dose were analyzed by generalized estimator equation, the probability of GC discontinuation was assessed using Kaplan-Meier curve, and predictors of GC discontinuation were analyzed by Cox regression. Patients with <12 months of follow-up were excluded for the sensitivity analysis. RESULTS: Among 1,196 patients (85.4% female; median age 56.4 years), 880 (73.6%) received IM. Over a median 12-month follow-up, 34.3% (410 cases) discontinued GC, with significantly higher rates in the IM group (40.8% vs. 16.1% in WM; P<0.05). GC dose declined progressively, with IM patients demonstrating faster reductions (median 3.75 mg vs. 5.00 mg in WM at 12 months; P<0.05). Multivariate Cox analysis identified age <60 years [P<0.001, hazard ratios (HR)=2.142, 95% confidence interval (CI): 1.523-3.012], IM therapy (P=0.001, HR=2.175, 95% CI: 1.369-3.456), baseline GC dose ⩽7.5 mg (P=0.003, HR=1.637, 95% CI: 1.177-2.275), and absence of non-steroidal anti-inflammatory drugs use (P=0.001, HR=2.546, 95% CI: 1.432-4.527) as significant predictors of GC discontinuation. Sensitivity analysis (545 cases) confirmed these findings. CONCLUSIONS RA patients receiving CM face difficulties in following guideline-recommended GC discontinuation protocols. IM can promote GC discontinuation and is a promising strategy to reduce GC dependency in RA management. (Trial registration: ClinicalTrials.gov, No. NCT05219214).
Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Arthritis, Rheumatoid/drug therapy* ; Glucocorticoids/therapeutic use* ; Medicine, Chinese Traditional ; Retrospective Studies

(+)-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 investigate the effects of peripheral blood neutrophil infiltration on the polarization regulation of cerebral resident microglia under a permanent ischemic stroke model.Methods Fifty-eight C57BL/6 mice were divided into two groups.One group was sham group,and the other group of mice was subjected to permanent middle cerebral artery occlusion surgery.Mice were euthanized 48 hours,7 days,14 days,and 30 days after surgery for tissue collection.Western blotting was used to detect expression levels of M1 microglia markers CD 16,M2 microglia marker arginase 1(Arg1),inflammatory cytokine interleukin-1 β(IL-1β),and neutrophil marker myeloperoxidase(MPO)in brain tissue.Immunofluorescence histochemical staining was used to assess neutrophil infiltration and M2 microglial distribution around the infarct area in brain sections.In vitro,purified neutrophils were co-cultured with BV2 microglial cells.After lipopolysaccharide stimulation,the phagocytosis of neutrophils by BV2 cells was observed,and the expression levels of CD16 and Arg1 proteins in BV2 cells were detected.Results Western blotting showed that the levels of CD16(P＜0.05),IL-1β(P＜0.001),and MPO(P＜0.05)in brain tissue increased significantly 48 hours and 7 days after surgery,then decreased,with MPO expression returning to normal levels 30 days after surgery.Immunofluorescence showed a significant increase of MPO-positive cells around the infarct area of the mouse cerebral cortex 48 hours after surgery(P＜0.001),followed by a decrease(P＜0.05).The number of ionized calcium binding adapter molecule 1(Iba1)and MPO double-positive cells gradually increased after surgery,and reached their peak at 14 days(P＜0.05).Iba1 and Arg1 double-positive cells also increased significantly 7 days(P＜0.05)and 14 days(P＜0.01)after surgery.In vitro,co-culture experiments showed that after BV2 phagocytosing neutrophils,CD 16(P＜0.05)significantly decreased and Arg1 significantly upregulated(P＜0.05).Conclusion In a permanent ischemic stroke model,microglia transition from M1 to M2 type after phagocytosing neutrophils,and the injured brain area changes from pro-inflammatory state to anti-inflammatory state.

Cardiac surgery patients often present with multiple comorbidities,the risk of periop-erative complications and the complexity of postoperative rehabilitation have significantly increased,posing higher demands on comprehensive perioperative management.Preoperative exercise pre-reha-bilitation,as a multidisciplinary collaborative intervention strategy,has been demonstrated to signifi-cantly improve the clinical prognosis of patients undergoing elective cardiac surgery by enhancing their cardiopulmonary function,muscle strength,and overall physiological functional reserve,thereby in-creasing the body's tolerance to surgical stress.Although phase-specific research achievements have been made domestically and internationally in the field of exercise pre-rehabilitation,its standardized implementation and clinical translation on a global scale still face numerous obstacles,necessitating systematic review and in-depth exploration.Therefore,this study aimed to conduct a systematic re-view of the intervention protocols,clinical efficacy,safety,and feasibility of preoperative exercise pre-rehabilitation in patients undergoing elective cardiac surgery,with the goal of providing theoretical evidence and practical references for optimizing perioperative management pathways and promoting the implementation of enhanced recovery after surgery concepts.

Objective:To explore the feasibility of using the large-scale language model ChatGPT to focus on research hotspots in the field of clinical medical education management,aiming to accelerate the scientific research process in this field.Methods:First,six key topics in the field were selected,and ChatGPT was guided to automatically generate the five most urgent or important research hotspots in each topic through questioning.Then,six clinical medical education managers were organized to use the five-point Likert scale to evaluate the research hotspots generated by ChatGPT from five dimensions,including pertinence,humanity,dialectics,expansion,and originality.Finally,the evaluation results were analyzed from multiple perspectives based on descriptive statistics,score similarity,and indicator correlation.Results:The research hotspots generated by ChatGPT performed excellently in terms of topic specificity,and were also satisfactory in terms of humanistic,dialectical,and expansive aspects,but performed mediocrely in terms of originality.Conclusion:ChatGPT can serve as an auxiliary tool to focus on research hotspots in clinical medical education management,but more efforts are still needed to enhance the originality of the research hotspots it generates.However,when using ChatGPT to focus on research hotspots,there are a series of ethical risks,including false and abusive data,discrimination and bias in algorithms,as well as academic dishonesty and misconduct.From the technical perspective,researchers can integrate the focused results of multiple large-scale language models,and utilize data and algorithm diversity to avoid ethical risks.From the application perspective,individual identification,group argumentation,and other means can be utilized,and carefully examined with critical thinking to avoid ethical risks.

Objective To explore the best preparation process and performance characterization of microcapsules containing ethanol extract from galangal.Methods With gum arabic(GA)-chitosan(CS)as capsule wall material,microcapsules were prepared by complex coacervation method.With drug loading and encapsulation efficiency as indexes,the optimal preparation technology of microcapsules was screened by orthogonal design method.The content of ethanol extract of galangal in microcapsules was determined by high performance liquid chromatography(HPLC).The prepared microcapsules were characterized by infrared spectrometer and scanning electron microscope.Results The optimum preparation conditions of microcapsules containing galangal ethanol extract were as follows:wall material ratio(GA/CS)6∶1,core to wall ratio 1∶1,coagulation time 45 minutes,curing agent dosage 3 mL.Under these conditions,the drug loading and encapsulation efficiency of microcapsules containing galangal ethanol extract were 27.17%and 80.07%,respectively,and the sustained release performance of microcapsules of galangal ethanol extract was superior to that of galangal ethanol extract.Conclusion The preparation of microcapsules containing galangal ethanol extract by complex coacervation method has good encapsulation,and the method is simple,stable and reliable,and has high feasibility.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective:To determine the differential expressions of long non-coding RNA(lncRNA)and messenger RNA(mRNA)in normal and asthenospermia(AS)men and analyze their biological significance in AS.Methods:We isolated and ex-tracted total RNAs from 9 normal and 9 AS sperm samples,determined the expressions of RNAs in the sperm using the DNBSEQ se-quencing platform,and analyzed their relevant functions by gene ontology enrichment(GO)and Kyoto encyclopedia of genes and ge-nomes pathway(KEGG)analyses.Results:An average of 10.64G data was generated per group,with 282 185 RNAs detected,in-cluding 107 009 lncRNAs.Among the total number of lncRNAs,15 157 were differentially expressed,2 190 upregulated and 12 967 downregulated;and among the 19 514 mRNAs,13 736 were differentially expressed,4 995 upregulated and 8 741 downregulated.Differentially expressed genes were enriched mainly in the sperm cell membrane and the pathways related to the ion channel functions,sperm development and fertilization.Conclusion:Differentially expressed lncRNAs and mRNAs can be identified by sequencing a-nalysis of AS and normal sperm.Regulation of sperm function through membrane ion channels may contribute to the development of AS,which provides a molecular basis for further research on AS.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.