ObjectiveTo identify the pathogen species responsible for the wilt disease of Tetradium ruticarpum in Chongqing， investigate there biological characteristics， and screen effective fungicides， so as to provide a theoretical basis for disease control in production. MethodsThe pathogen was isolated via the tissue culture method. Pathogenicity was verified according to Koch's postulates. The pathogen was identified based on morphological characteristics and multi-gene phylogenetic analysis. The mycelial growth rate method was used for biological characterization of the pathogen and fungicide screening. ResultsThe pathogen colonies were nearly circular with irregular edges， white， short， velvety aerial hyphae， and pale purple undersides. Macroconidia were colorless， sickle-shaped， with 3-5 septa， while microconidia were transparent， elliptical， aseptate or with 1-2 septa. Multi-gene phylogenetic analysis showed that the pathogen clustered in the same clade as Fusarium fujikuroi with 100% support， which， combined with morphological characteristics， identified the pathogen causing wilt of T. ruticarpum in Chongqing as F. fujikuroi. The optimal conditions for the mycelial growth of F. fujikuroi were mung bean agar （MBA） with glucose as the carbon source， beef extract and yeast powder as nitrogen sources， 28 ℃， pH 7.0， and alternating light/dark conditions. The optimal conditions for sporulation were potato dextrose agar （PDA） with glucose as the carbon source， beef extract as the nitrogen source， 28 ℃， pH 7.0， and complete darkness. Among chemical fungicides， phenazine-1-carboxylic acid exhibited the strongest inhibitory effect on F. fujikuroi. Shenqinmycin and tetramycin were the most effective bio-fungicides. ConclusionThis study is the first to report F. fujikuroi as the causal agent of wilt disease in T. rutaecarpa. The chemical fungicide phenazine-1-carboxylic acid and the bio-fungicides shenqinmycin and tetramycin showed strong inhibitory effects against F. fujikuroi.

OBJECTIVE To study the pharmacokinetic characteristics of ciprofol in pregnant and fetal rats， and provide reference for the application of ciprofol in cesarean section. METHODS Eight pregnant rats were selected. A single dose of 2.4 mg/kg of ciprofol was administered via the tail vein. One fetal rat was selected at 2， 4， 8， 12， 16， 25， 35， 45， 60， and 90 minutes respectively after ciprofol administration. Subsequently， whole blood samples were collected simultaneously from both the pregnant rats and fetal rats. HPLC-MS/MS method was used to determine the concentration of ciprofol in the bodies of pregnant and fetal rats. The ratios of fetal-to-maternal blood concentrations （F/M ratios） at each time point were calculated， and the F/M-time curves were plotted. Subsequently， non-compartmental pharmacokinetic parameters were computed using DAS 2.0 software. RESULTS Compared with pregnant rats， cmax， AUC0-90 min and AUC0-∞ of ciprofol in fetal rats were decreased significantly， while MRT was increased significantly （P＜0.05）. The F/M curve of ciprofol initially increased and then decreased， and between 0.16- 0.84， reaching a maximum value of 0.84 at 45 minutes. CONCLUSIONS Ciprofol can penetrate the placental barrier， and there are significant differences in pharmacokinetic parameters between pregnant and fetal rats. Moreover， the exposure level of ciprofol in fetal rats is much lower than that in pregnant rats. Therefore， ciprofol shows promise as an ideal anesthetic agent for cesarean section delivery.

Hepatic ischemia-reperfusion injury （HIRI） is an inevitable major complication during surgical procedures such as liver transplantation and partial hepatectomy， and its prevention and treatment are hotspots and difficulties in clinical practice. This article reviews the mechanism of injury caused by energy metabolism disorders during liver ischemia-reperfusion and related treatment strategies and summarizes the current advances in metabolism-related therapies， in order to provide new ideas for further clarifying the onset mechanism of HIRI and exploring effective clinical prevention and treatment strategies for HIRI.

BACKGROUND: The effects of human umbilical cord-derived mesenchymal stem cell (UC-MSC) treatment on coronavirus disease 2019 (COVID-19) patients have been preliminarily characterized. However, real-world data on the safety and efficacy of intravenous transfusions of MSCs in hospitalized COVID-19 patients at the convalescent stage remain to be reported. METHODS: This was a single-arm, multicenter, real-word study in which a contemporaneous external control was included as the control group. Besides, severe and critical COVID-19 patients were considered together as the severe group, given the small number of critical patients. For a total of 110 patients, 21 moderate patients and 31 severe patients were enrolled in the MSC treatment group, while 26 moderate patients and 32 severe patients were enrolled in the control group. All patients received standard treatment. The MSC treatment patients additionally received intravenous infusions of MSCs at a dose of 4 × 10 7 cells on days 0, 3, and 6, respectively. The clinical outcomes, including adverse events (AEs), lung lesion proportion on chest computed tomography, pulmonary function, 6-min walking distance (6-MWD), clinical symptoms, and laboratory parameters, were measured on days 28, 90, 180, 270, and 360 during the follow-up visits. RESULTS: In patients with moderate COVID-19, MSC treatment improved pulmonary function parameters, including forced expiratory volume in the first second (FEV1) and maximum forced vital capacity (VCmax) on days 28 (FEV1, 2.75 [2.35, 3.23] vs . 2.11 [1.96, 2.35], P  = 0.008; VCmax, 2.92 [2.55, 3.60] vs . 2.47 [2.18, 2.68], P  = 0.041), 90 (FEV1, 2.93 [2.63, 3.27] vs . 2.38 [2.24, 2.63], P  = 0.017; VCmax, 3.52 [3.02, 3.80] vs . 2.59 [2.45, 3.15], P  = 0.017), and 360 (FEV1, 2.91 [2.75, 3.18] vs . 2.30 [2.16, 2.70], P  = 0.019; VCmax,3.61 [3.35, 3.97] vs . 2.69 [2.56, 3.23], P  = 0.036) compared with the controls. In addition, in severe patients, MSC treatment notably reduced the proportion of ground-glass lesions in the whole lung volume on day 90 ( P  = 0.045) compared with the controls. No difference in the incidence of AEs was observed between the two groups. Similarly, no significant differences were found in the 6-MWD, D-dimer levels, or interleukin-6 concentrations between the MSC and control groups. CONCLUSIONS: Our results demonstrate the safety and potential of MSC treatment for improved lung lesions and pulmonary function in convalescent COVID-19 patients. However, comprehensive and long-term studies are required to confirm the efficacy of MSC treatment. TRIAL REGISTRATION Chinese Clinical Trial Registry, ChiCTR2000031430.
Humans ; COVID-19/therapy* ; Female ; Male ; Mesenchymal Stem Cell Transplantation/adverse effects* ; Middle Aged ; Adult ; Umbilical Cord/cytology* ; Mesenchymal Stem Cells/cytology* ; SARS-CoV-2 ; Aged ; Treatment Outcome

Somatostatin receptor 1 (SSTR1) is a crucial therapeutic target for various neuroendocrine and oncological disorders. Current SSTR1-targeted treatments, including the first-generation somatostatin analog lanreotide (Lan) and the second-generation analog pasireotide (Pas), show promise but encounter challenges related to selectivity and efficacy. This study presents high-resolution cryo-electron microscopy structures of SSTR1 complexed with Lan or Pas, revealing the distinct mechanisms of ligand-binding and activation. These structures illustrate unique conformational changes in the SSTR1 orthosteric pocket induced by each ligand, which are critical for receptor activation and ligand selectivity. Combined with the biochemical assays and molecular dynamics simulations, our results provide a comparative analysis of binding characteristics within the SSTR family, highlighting subtle differences in SSTR1 activation by Lan and Pas. These insights pave the way for designing next-generation therapies with enhanced efficacy and reduced side effects through improved receptor subtype selectivity.

To develop a method for determining the antibody-dependent cell-mediated phagocytosis (ADCP) activity of human epidermal growth factor receptor 2 (HER2)-targeted antibody drug conjugate (ADC) based on the reporter gene assay, we established an ADCP activity assay with Jurkat/NFAT/FcγRIIa cells as the effector cells and BT474 as the target cells. Then, the target cell density, the ratio of effector to target cells, the target cell adhesion time, the incubation time for drug administration, and the induction time after adding effector cells were optimized by the method of design of experiment (DOE). The method showed a significant dose-response relationship, which was complied with the four-parameter equation: y=(A-D)/[1+(x/C)^B]+D. The durability ranges of the target cell density, the ratio of effector to target cells, the target cell adhesion time, the incubation time for drug administration, and the induction time after adding effector cells were (2.5-4.0)×10⁵ cells/mL, 3-5, 1.0-2.0 h, 0 h, and 5.0-6.0 h, respectively. The results of the methodological validation showed that the linear equation was y=1.106 8x-0.011 6, r=0.969 2. The established method showed the relative accuracy ranging from -6.59% to 2.98% and the geometric coefficient of variation less than 11% in the intermediate precision test. Furthermore, the method was target-specific. The method was then applied to the determination of ADCP activity of HER2-targeted ADC, demonstrating the result of (103.5±5.7)%. We developed a reporter gene assay for determining the ADCP activity of HER2-targeted ADC and the assay demonstrated high accuracy and good reproducibility, which proposes a highly efficient and approache for evaluating ADCP effect of this HER2-targeted ADC, and also provides a referable technique for characterizing the Fc effector functions of ADCs with diverse targets.
Humans ; Receptor, ErbB-2/immunology* ; Phagocytosis/drug effects* ; Immunoconjugates/immunology* ; Genes, Reporter ; Antibody-Dependent Cell Cytotoxicity ; Jurkat Cells

Glycosylation modification is an important post-translational modification of proteins, which participates in regulating protein half-life, biological activity, and immunogenicity, thereby affecting their functions. Glycoproteins expressed in Pichia pastoris predominantly carry high-mannose type glycans, primarily composed of mannose residues, which starkly contrasts with the complex-type glycans synthesized by mammalian cells. This study aims to transform the high mannose glycosylation modification of P. pastoris into a hybrid glycosylation modification similar to that of mammalian cells through genetic engineering technology. We introduced the mannosidase Ⅰ gene (MDSⅠ) from Trichoderma viride and the human β-1,2-N-acetylglucosaminyltransferase I gene (GnTⅠ) into a previously constructed P. pastoris strain (∆och1) capable of producing Man₈GlcNAc₂ glycans. To precisely regulate the expression of MDSⅠ and GnTⅠ, we designed various promoter combinations, including the strong inducible AOX promoter and the constitutive GAP promoter. The receptor-binding domain (RBD, residues 377-588) of the spike protein from the Middle East respiratory syndrome coronavirus (MERS-CoV) was selected as the reporter protein for this investigation (MERS-RBD). The N-glycosylation profile of MERS-RBD was systematically analyzed using PNGase F digestion coupled with mass spectrometry. The results showed that after the knockout of och1 and the introduction of MDSⅠ and GnTⅠ genes with different promoter combinations, P. pastoris strains capable of producing GlcNAcMan₅GlcNAc₂ glycans were successfully generated. When the AOX promoter was used to control the MDSⅠ gene and the GAP promoter was used to control the GnTⅠ gene, the engineered strain exhibited the highest proportion of hybrid-type GlcNAcMan₅GlcNAc₂ glycans, which accounted for 68.38% of the total N-glycosylation. In conclusion, we successfully engineered a P. pastoris strain capable of synthesizing hybrid-type GlcNAcMan₅GlcNAc₂ glycans, establishing a foundation for subsequent research on the biosynthesis of complex-type N-glycans in P. pastoris.
Glycosylation ; Glycoproteins/genetics* ; Polysaccharides/metabolism* ; N-Acetylglucosaminyltransferases/metabolism* ; Pichia/metabolism* ; Humans ; Mannosidases/metabolism* ; Genetic Engineering ; Trichoderma/genetics* ; Recombinant Proteins/genetics* ; Saccharomycetales

Objective:To study the distribution of drug resistance genes and virulence genes in multidrug-resistant Salmonella typhimurium strains.Methods:A total of 96 strains of Salmonella typhimurium were collected，and drug sensitivity tests were performed to evaluate the drug resistance and multidrug-resistance of Salmonella typhimurium.Multidrug-resistant Salmonella typhimurium strains were selected to conducted whole genome sequencing，and the distribution of drug resistance genes and virulence genes in the strain were analyzed.Results:Salmonella typhimurium strains had the highest resistance rates to ampicillin and ampicillin/sulbactam，with 89.58% and 76.04%，respectively.Followed by trimethoprim/sulfamethoxazole，ceftriaxone，and aztreonam，with 47.92%，38.54% and 33.33%，respectively，and low resistance rates to ciprofloxacin and levofloxacin，with 8.33% and 4.17%，respectively.Ninety-six strains were all sensitive to carbapenem antibiotics and piperacillin/tazobactam.Fifty-seven strains（59.38%）of Salmonella typhimurium showed multidrug-resistance.Resistance genes were detected in all 57 multidrug-resistant Salmonella typhimurium strains,with higher carrier rates of 98.25%,77.19%,and 59.65% for aac(6')-Iaa,aadA22,and blaTEM-1B,respectively.The multidrug-resistant Salmonella typhimurium strains had the highest carrier rates for invA，sipA，sseL，and sopB.Conclusion:Multidrug-resistant Salmonella typhimurium strains have a high incidence and a high carrier rate for multiple drug resistance genes and virulence genes.The monitoring and prevention of Salmonella typhimurium should be strengthened in the clinic in order to reduce the spreading epidemic of multidrug-resistant strains.

AIM:To investigate the impact of honokiol(HKL),an activator of silent information regulator 3(SIRT3),on postoperative cognitive dysfunction(POCD)in mice,and to explore the potential mechanisms.METHODS:Ten-month-old male C57/BL6 mice were randomly divided into control(Con)group,surgical(Sur)group and Sur+HKL group(n=10).The mice in Sur+HKL group were intraperitoneally injected with HKL for 7 d before modeling.The mice in Sur and Sur+HKL groups underwent tibial fracture open reduction and internal fixation to establish the POCD model.The assessment of cognitive function was conducted using the open-field test(OFT),novel object recognition test(NORT),Morris water maze test(MWMT),and Y-maze test(YMT).Nissl staining was employed to assess the morphology,struc-ture and vitality of hippocampal and cortical neurons in mice.The protein expression of glutathione peroxidase 4(GPX4),solute carrier family 7 member 11(SLC7A11),acyl coenzyme A synthetase long-chain family member 4(ACSL4),SIRT3 and nuclear factor E2-related factor 2(NRF2)in the mouse hippocampus was detected by Western blot,while im-munofluorescence staining was utilized to determine GPX4 level in mouse neurons.RESULTS:No statistically signifi-cant differences were observed among the groups in terms of total distance moved and central zone exploration during the OFT(P>0.05).However,the results from the NORT and YMT indicated that the mice in Sur group exhibited significant-ly lower recognition indexes,reduced alternation rates(P<0.01),and decreased percentages of entries and crossing time into the new arm after side arm blockade(P<0.01),when compared with Con group.Furthermore,the mice in Sur group demonstrated a slower decrease in latency during the learning period of MWMT,while significantly lower latency,fewer crossing number and lower percentage of time in the target quadrant were observed during the testing period of MWMT(P<0.01).The above indicators were obviously enhanced in Sur+HKL group compared with Sur group(P<0.01).The results of Nissl staining indicated lighter neuronal staining in the hippocampal CA1 region and medial prefrontal cortex in Sur group,accompanied by a significant reduction in the number of Nissl-stained positive neurons(P<0.01).Notably,HKL pretreatment demonstrated a significant improvement in neuronal vitality.Analysis of Western blot revealed that compared with Con group,the expression of SIRT3,GPX4,SLC7A11 and NRF2 in Sur group was significantly reduced,while the expression of ACSL4 was significantly increased(P<0.05).However,these alterations were reversed after treatment with HKL(P<0.05).Immunofluorescence staining of hippocampal neurons corroborated the findings from Western blot analy-sis,demonstrating a notable decrease in GPX4 expression in hippocampal neurons of Sur group,which was significantly restored after HKL pretreatment(P<0.01).CONCLUSION:Treatment with HKL attenuates POCD in mice,potentially through its inhibitory effect on hippocampal neuronal ferroptosis.

Objective:To investigate the correlation between plasma total α-synuclein (α-syn), phosphorylated α-synuclein (p-α-syn), neurofilament light chain(NfL) and subtypes of Parkinson disease(PD).Methods:A total of 62 PD patients admitted to the Department of Neurology, the Affiliated Huai 'an No. 1 People 's Hospital of Nanjing Medical University from September 2021 to January 2023 were selected and scored on the Hoehn-Yahr stage(H-Y), unified Parkinson's disease rating scale Ⅲ(UPDRS-Ⅲ), levodopa equivalent daily dosage(LEDD), mini-mental state examination(MMSE), Parkinson disease quality of life questionnaire(PDQ-39) and activities of daily living(ADL). During the same period, 25 healthy individuals matched in age and sex were enrolled as the control group (HC). Clinical characteristics and blood samples were collected. The plasma levels of α-syn, p-α-syn and NfL were detected by enzyme-linked immunosorbent assay(ELISA). PD patients were divided into tremor dominant type (TD, n=27) and akinetic-rigid dominant type (AR, n=35) based on UPDRS-Ⅲ scores. Multifactorial Logistic regression analysis was performed by SPSS 25.0 software to determine the influencing factors of subtypes of Parkinson disease. The receiver operating characteristic (ROC) curve was used to determine the optimal cut-off point of plasma NfL between the AR type and the TD type. Results:Plasma α-syn, p-α-syn, NfL levels in the PD group were significantly higher than those of the HC group ( Z=-2.537, -6.580, -7.101, all P<0.05). There were statistically significant differences between the AR type and the TD type in disease duration, H-Y stage, UPDRS-Ⅲ scores, LEDD and MMSE scores ( Z=-2.503, -3.021, -2.025, -2.086, -2.409, all P<0.05). While no significant difference was found in plasma α-syn and p-α-syn levels between the AR type and TD type ( Z=-0.341, -0.085, both P>0.05), the plasma NfL levels were notably higher in the AR type(92.79(16.84, 117.53) pg/mL) compared to the TD type (12.10(6.99, 100.17) pg/mL)( Z=-2.236, P<0.05). Plasma NfL levels were correlated with rigidity scores ( r=0.438, P<0.001), UPDRS-Ⅲ scores ( r=0.337, P<0.05) and motor subtypes ( r=0.286, P<0.05) in PD patients. Multivariate Logistic regression analysis showed that NfL was risk factor for AR( B=0.002, OR=1.002, 95% CI=1.001-1.003, P=0.017). The ROC curve analysis indicated that plasma NfL levels could predict different subtypes of PD with an AUC=0.667, optimal cutoff =26.527. Conclusion:There is a correlation between elevated plasma NfL levels and the occurrence of AR type of PD, suggesting that nerve injury is probably involved in the occurrence and progression of various motor subtypes of PD.