Metformin has been demonstrated to attenuate hyperglycaemia by modulating the gut microbiota. However, the mechanisms through which the microbiome mediates metformin monotherapy failure (MMF) are unclear. Herein, in a prospective clinical cohort study of newly diagnosed type 2 diabetes mellitus (T2DM) patients treated with metformin monotherapy, metagenomic sequencing of faecal samples revealed that Phocaeicola vulgatus abundance was approximately 12 times higher in nonresponders than in responders. P. vulgatus rapidly hydrolysed taurine-conjugated bile acids, leading to ceramide accumulation and reversing the improvements in glucose intolerance conferred by metformin in high-fat diet-fed mice. Interestingly, C22:0 ceramide bound to mitochondrial fission factor to induce mitochondrial fragmentation and impair hepatic oxidative phosphorylation in P. vulgatus-colonized hyperglycaemic mice, which could be exacerbated by metformin. This work suggests that metformin may be unsuitable for P. vulgatus-rich T2DM patients and that clinicians should be aware of metformin toxicity to mitochondria. Suppressing P. vulgatus growth with cefaclor or improving mitochondrial function using adenosylcobalamin may represent simple, safe, effective therapeutic strategies for addressing MMF.

Although a single nucleotide polymorphism for N-acetyltransferase 10 (NAT10) has been identified in patients with early-onset stroke, the role of NAT10 in ischemic injury and the related underlying mechanisms remains elusive. Here, we provide evidence that NAT10, the only known RNA N4-acetylcytidine (ac4C) modification "writer", is increased in the damaged cortex of patients with acute ischemic stroke and the peri-infarct cortex of mice subjected to photothrombotic (PT) stroke. Pharmacological inhibition of NAT10 with remodelin on Days 3-7 post-stroke or astrocytic depletion of NAT10 via targeted virus attenuates ischemia-induced infarction and improves functional recovery in PT mice. Mechanistically, NAT10 enhances ac4C acetylation of the inflammatory cytokine tissue inhibitor of metalloproteinase 1 (Timp1) mRNA transcript, which increases TIMP1 expression and results in the accumulation of microtubule-associated protein 1 light chain 3 (LC3) and progression of astrocyte autophagy. These findings demonstrate that NAT10 regulates astrocyte autophagy by targeting Timp1 ac4C after stroke. This study highlights the critical role of ac4C in the regulation of astrocyte autophagy and proposes a promising strategy to improve post-stroke outcomes via NAT10 inhibition.

O-acetyl-L-homoserine (OAH) is a promising platform compound for the production of L-methionine and other valuable compounds, while its low yield and low conversion rate limit the industrial application. To solve these problems, we constructed a strain for high OAH production with the previously constructed L-homoserine producer Escherichia coli HS33 as the chassis by systematic metabolic engineering. Firstly, PEP accumulation, pyruvate utilization, and OAH synthesis pathway (overexpressing aspB, aspA, and thrA^C1034T) were enhanced to obtain an initial strain accumulating 13.37 g/L OAH. Subsequently, the co-factor synthesis genes were integrated to supply reducing power and energy, which increased the yield to 15.79 g/L. The OAH yield of the engineered strain OAH28 was further increased to 17.49 g/L by strengthening the acetic acid reuse pathway, improving the supply of acetyl-CoA, and regulating the expression of MetX from different sources. Finally, in a 5 L fermenter, OAH28 achieved an OAH titer of 47.12 g/L, with a glucose conversion rate of 32% and productivity of 0.59 g/(L·h). The results lay a foundation for increasing the OAH production by metabolic engineering and give insights into the industrial production of OAH.
Metabolic Engineering/methods* ; Escherichia coli/genetics* ; Homoserine/biosynthesis* ; Fermentation

Synthetic biology is a crucial tool for the development of the bio-industry and bio-economy, representing a significant aspect of new quality productive forces. As a core course for graduate students in bioengineering, Synthetic Biology plays a vital role in ensuring the supply of essential talents for the development of the bio-industry in the new era. To better serve regional economic development and provide high-level talents for China's progress in the bio-industry, we analyzed typical issues encountered in the past teaching activities, set up a multi-disciplinary teaching team, optimized the course contents, adjusted the teaching mode, and mobilized students' learning interest. With the application of scientific research project as the starting point, we guided students to think and discuss deeply through the simulation of application writing and project defense, which improved students' critical thinking and innovative thinking. With industrialization as a focus, we explored a new training model combining production, education, and research through the joint practice base of the university and enterprises introduced typical cases of biomanufacturing to encourage students to engage in scientific research. The teaching reform significantly enhances the comprehensive abilities and national sentiments of graduate students. This paper hopes to serve as a reference for colleagues engaged in teaching in this field.
Synthetic Biology/education* ; Teaching ; China ; Humans

Objective: To identify an optimal back-flush solution for leukocyte-depleted filters that maximizes peripheral blood mononuclear cell (PBMC) recovery with high viability, long-term storage stability, and sterility of the harvested residues, thereby providing a clinically translatable strategy. Methods: Three sterile bag-packaged solutions—Saline, Solvent, and Hanks' balanced salt solution (HBSS)—were used to back-flush randomly assigned leukocyte-depleted filters. Nucleated cell recovery rate and viability of the harvested residues were compared. The optimal solution identified was applied to an expanded sample set. PBMC viability and yield were evaluated after 1h vs 48h storage of the residues. PBMCs isolated from the residues were cryopreserved in liquid nitrogen for 1 month, followed by post-thaw comparisons of viability and T-cell expansion capacity. Results: The Solvent group achieved the highest and most consistent nucleated cell recovery rate. Post-flush recovery rate from filters after 400 mL whole blood processing was (21.3±1.6)% for the Solvent group, significantly higher than Saline group (19.2±6.3)% and HBSS group (11.2±5.0)%, with residues from all groups maintaining viability >90%. No biologically significant difference in residue viability was observed between 48h vs 1h storage groups (93.3±2.3)% vs (95.7±1.8)%). PBMC recovery rates from residues showed no statistical difference between 48h vs 1h storage groups [(48.2%±9.5%)vs (40.41%±8.35%), P>0.05], with (17.7±2.6)×10 cells. After 1-month cryopreservation and 10-day expansion, PBMCs isolated from 48-hour-stored residues retained (91.2±3.2)% viability and achieved a (61.9±15.9)-fold expansion. Conclusion: The bag-packaged Solvent, as a back-flush solution, enables sterile acquisition of leukocyte-depleted filter residues through closed-system tubing connections. These residues maintained PBMC viability and recovery rates after 48h storage at 2℃-8℃, with post-cryopreservation (1-month liquid nitrogen) viability and expansion capacity remaining stable. This protocol complies with blood bank regulatory criteria, addresses the concerns about the infectious window period in cell therapy raw materials, and provides a clinically translatable strategy for PBMC-based applications.

The multidisciplinary diagnosis and treatment (MDT) mode plays a positive role in diagnosing and treating difficult and complicated diseases, improving service quality, and promoting the construction of an integrated medical system. In March 2023, Zhejiang Provincial People′s Hospital had launched the " 6 New" MDT management practice to further improve the hospital′s inpatient MDT service level, including new concepts, new architectures, new standards, new processes, new models, and new quality control. This practice had improved the quality and efficiency of MDT management and promoted interdisciplinary integration by strengthening top-level design, establishing MDT leadership and quality control teams, developing relevant standards and specifications, enhancing the level of information management throughout the entire process, implementing diversified MDT models, and implementing quality control measures. As of July 2024, the hospital had established 80 MDT teams covering 30 clinical departments, conduct 120 MDT discussions for hospitalized cases per month, and with the continuous promotion of inpatient MDT work, the number of MDT teams and cases continued to increase. This practice had achieved good results and could provide references for other public hospitals in China to improve the level of inpatient MDT services.

Objective:To compare the efficacy of Ilizarov ring external fixation and unilateral rail external fixation in the treatment of infected bone defects following surgery for tibial fractures.Methods:A retrospective cohort study was conducted to analyze the clinical data of 50 patients with infected bone defects after surgery for tibial fractures, who were admitted to the 940th Hospital of the Joint Logistics Support Force of the PLA from August 2019 to November 2021, including 37 males and 13 females, aged 19-59 years [(42.2±8.8)years]. After debridement and osteotomy, 28 patients were treated with Ilizarov ring external fixation (Ilizarov group) and 22 with unilateral rail external fixation (unilateral fixation group). All the patients in the two groups had previously undergone internal fixation with plates or Kirschner wires for tibial fracture before bone transport. Bone transport started at one week for three stages after successful infection control and osteotomy and was conducted. The following parameters were compared between the two groups: frame-wearing time and healing index after bone transport, self-rating anxiety scale (SAS) grade at 6 months after bone transport, Paley score and Association for the Study and Application of the Method of Ilizarov (ASAMI) score at the last follow-up, Hospital for Special Surgery (HSS) knee score and Baird-Jackson ankle score on admission, after external fixator removal and at the last follow-up, and incidence of postoperative complications.Results:All the patients were followed up for 28-36 months [(32.5±1.6)months]. There were no significant differences in frame-wearing time or healing index between the two groups after bone transport ( P>0.05). At 6 months after bone transport, the SAS grade in the unilateral fixation group (13 patients with mild anxiety, 8 with moderate anxiety, and 1 with severe anxiety) was better than that in the Ilizarov group (6 patients with mild anxiety, 19 with moderate anxiety, 3 with severe anxiety) ( P<0.01). No significant differences were found in the Paley score or ASAMI score between the two groups at the last follow-up ( P>0.05). There were no significant differences in HSS knee score or Baird-Jackson ankle score between the two groups on admission, after external fixator removal or at the last follow-up ( P>0.05). No significant differences were observed in the incidence of pin tract infection, poor healing, infection in the bone elongation area, or re-fracture between the two groups ( P>0.05). The incidence of postoperative axial deviation was 0 in the Ilizarov group, lower than 18% in the unilateral fixation group (4/22) ( P<0.05). Conclusion:Although Ilizarov ring external fixation and unilateral rail external fixation demonstrate comparable efficacy in the treatment of infected bone defects after surgery for tibial fractures, the former provides superior mechanical stability and postoperative axial deviation correction, while the latter offers advantages in reducing psychological burden and enhancing treatment tolerance.

Objective:To investigate the expression and clinical significance of long noncoding RNA (lncRNA) AP006284.1 in bladder cancer tissues, and to analyze the regulatory effect and downstream mechanism of AP006284.1 knockdown on the proliferation and migration of bladder cancer cells. Methods:The expression of AP006284.1 in bladder cancer tissues, and the relationship between AP006284.1 expression and tumor stage and disease-free survival of bladder cancer patients were analyzed in the gene expression omnibus (GEO) database. AP006284.1 gene expression in bladder cancer cell lines, including MGH-U3, T24, UMUC-3, J82 and 5637, and bladder epithelial immortalized SV-HUC-1 cell were detected by real-time reverse transcription-PCR (RT-qPCR) assay. J82 cells were divided into the control group and the transfection group, and transfected with control plasmid and AP006284.1 knockdown plasmid, respectively. The effect of AP006284.1 knockdown on the proliferation of J82 cells was detected by RT-qPCR and cell counting kit-8 (CCK-8) assay. The effect of AP006284.1 knockdown on the migration of J82 cells was determined by the scratch healing assay. The target gene of AP006284.1 was predicted by LncRNA2Target and LncRNome databases. The target fragment of wild-type AP006284.1 ( AP006284.1-Wt) or mutant AP006284.1 ( AP006284.1-Mut) was constructed into pGL3 plasmid by dual luciferase gene reporter assay. J82 cells were co-transfected with miR-205-3p or miR-negtive control (miR-NC) to validate the targeting relationship between AP006284.1 and miR-205-3p. The correlation between miR-205-3p and AP006284.1 expression in bladder cancer tissues was further analyzed by the GEO database. The effect of AP006284.1 knockdown on the expression of miR-205-3p gene in J82 cells was detected by RT-qPCR assay. The effect of AP006284.1 knockdown on the expression of phosphorylated Ras protein (p-Ras), phosphorylated Raf protein (p-Raf), phosphorylated mitogen-activated protein kinase kinase (p-MEK), and phosphorylated extracellular signal-regulated kinase (p-ERK) of the ERK pathway was detected by Western blotting in J82 cells. Results:GEO database analysis showed that the relative expression of AP006284.1 in bladder cancer tissues ( n=304) was significantly higher than that in normal tissues ( n=28, P<0.01). The relative expression of AP006284.1 was positively correlated with the tumor stage of the bladder cancer patients ( P<0.01). Compared with bladder cancer patients with low expression of AP006284.1, patients with high expression had a lower disease-free survival ( P<0.01). Compared with the SV-HUC-1 cell (1.02±0.34), the expression level of AP006284.1 gene was upregulated in MGH-U3 cell (5.77±0.37), T24 cell (3.02±0.40), UMUC-3 cell (3.62±0.59), J82 cell (7.19±0.24) and 5637 cell (5.59±0.30) (all P<0.01). The expression level of the AP006284.1 gene was the highest in J82 cells, therefore, the J82 cells were selected for the study. The expression level of AP006284.1 gene in the control group (7.20±0.26) was 6.92 times higher than that in the transfection group (1.04±0.28, t=16.16, P<0.01). Compared with the control group (0.74±0.11, 1.35±0.09, 1.63±0.14, 1.74±0.11), the absorbance ( A) values of J82 cells in the transfection group (0.49±0.06, 0.95±0.14, 1.09±0.08, 1.13±0.11) were reduced than those in the control group at the 24, 36, 48 and 60 h after AP006284.1 knockdown (all P<0.05). The migration distance of J82 cells in the control group was significantly longer than that in the transfection group. The migration rate of the control group [(65.03±6.20)%], which was 2.58 times higher than that of the transfection group [(25.22±3.45)%, t=5.61, P<0.01]. The target site of miR-205-3p containing AP006284.1 was predicted by LncRNA2Target and LncRNome databases. Compared with miR-NC group (1.00±0.11), the relative activity of dual luciferase of AP006284.1-Wt gene was significantly downregulated in the miR-205-3p group (0.31±0.07, t=5.47, P<0.01). Compared with the miR-NC group (0.97±0.14), the relative activity of dual luciferase of AP006284.1-Mut vector (0.98±0.07) was not significantly change ( t=0.09, P>0.05). The GEO database analysis showed that the expression of AP006284.1 in bladder cancer tissues was negatively correlated with the expression of miR-205-3p ( P<0.01). The expression level of miR-205-3p gene in the transfection group (5.42±0.24) was 5.21 times higher than that in the control group (1.04±0.40, t=9.40, P<0.01). Compared with the control group (3.22±0.17, 5.56±0.19, 4.38±0.17, 5.74±0.36), the expressions of p-Ras (2.33±0.12), p-Raf (1.61±0.20), p-MEK (1.57±0.25), and p-ERK (2.40±0.28) of the ERK pathway were decreased in the transfected J82 cells (all P<0.01). Conclusions:AP006284.1 is highly expressed in bladder cancer tissues. Knockdown of AP006284.1 can inhibit the proliferation and migration of bladder cancer cells by regulating the miR-205-3p and ERK pathway proteins.

Objective:To establish an HPLC method to simultaneously determine the contents of 7 components, including Cardol triene, Cardol diene, (8'Z,11'Z,14'Z)-5-(Heptadeca-8',11',14'-trienyl)benzene-1,3-diol, Alkylresorcinol B, 5-(8'Z,11'Z-heptadecadienyl)-1,3-benzenediol, Adipostatin A, and 5-(11'Z-heptadecenyl)-resorcinol in Embelia laeta (L.) Mez. Methods:Chromatographic column was Arcus EP-C18(4.6 mm×250 mm, 5 μm); mobile phase was methanol-water (90∶10); column temperature was 25 ℃; flow rate was 1 ml/min; detection wavelength was 220 nm; the injection volume was 10 μl.Results:The 7 compounds in Embelia laeta (L.) Mez showed good linear relationships, which sample recovery rate ranges from 97.69%- 100.62%. The average contents of the 7 components from 9 origins were 3.099 9, 6.246 3, 9.942 8, 4.093 7, 2.180 3, 0.960 2, 1.855 9 mg/g. Conclusion:The established HPLC method for simultaneous determination of the contents of 7 components in Embelia laeta (L.) Mez is feasible, which can provide references for further development and utilization of Embelia laeta (L.) Mez.

OBJECTIVES: To characterize the biological properties of double-negative T (DNT) cells isolated from leukoreduction filter residues. METHODS: Leukoreduction filters containing residues from 400 mL whole blood units (n=6) were collected from a blood center. Filters were back-flushed with normal saline, and the eluate was concentrated to obtain leukoreduction filter residues. Leukocytes in the residues were counted by dual-fluorescence staining. DNT cells were then isolated from the residues using antibody-mediated adsorption and density gradient centrifugation. Both cryopreserved and fresh unstimulated DNT cells derived from the residues were subjected to in vitro culture. Following culture, cells were assessed for expansion fold, viability, immunophenotype, differentiation status, and cytotoxicity against target cells using dual-fluorescence staining and flow cytometry, with comparisons made to DNT cells derived from whole blood. RESULTS: The leukocyte recovery rate achieved through reverse flushing of the leukocyte reduction filter was (41.9±14.7)%. Compared to whole blood, the DNT cell starting material obtained from filter residues showed no significant difference in total T-cell content (P>0.05). However, the viability and purity of the resulting DNT cell starting materials were significantly lower (both P<0.05). After 17 days of culture, DNT cells from filter residues and whole blood showed no significant differences in expansion fold, immunophenotype, differentiation status, or cytotoxicity toward target cells (all P>0.05). However, the viability of DNT cells from residues was significantly lower than that of whole blood-derived DNT cells [(86.0±4.2)% vs. (92.2±1.2)%, P<0.05]. After thawing (post 3 or 15 days of cryopreservation) and 17 days of culture, DNT cell starting materials from residues showed comparable immunophenotype, expansion fold, and differentiation status to their non-cryopreserved counterparts from the same source (all P>0.05). However, the viability of DNT cells cryopreserved for 3 days [92.4% (91.8%, 92.8%)] and the cytotoxicity against target cells of those cryopreserved for 15 days [91.3% (89.4%, 95.1%)] were significantly higher than those of non-cryopreserved DNT cells [87.8% (82.0%, 89.0%) and 70.9% (67.3%, 80.2%), respectively] (P<0.05). CONCLUSIONS DNT cells derived from leukoreduction filter residues exhibited highly comparable characteristics to those from whole blood in terms of expansion, purity, differentiation, and biological potency. Furthermore, their biological activity post-cryopreservation and revival remained largely similar to non-cryopreserved cells. These findings suggest that leukoreduction filter residues represent a promising alternative source of starting material for manufacturing off-the-shelf, allogeneic DNT cell therapeutics.