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

Background Mitochondrial biogenesis is pivotal in coal workers' pneumoconiosis fibrosis, yet the role of the peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α)-nuclear respiratory factor 1 (NRF1)-mitochondrial transcription factor A (TFAM) pathway inmitochondrial biogenesis remains elusive, warranting further investigation. Objective To elucidate the role of the PGC-1α-NRF1-TFAM pathway in mitochondrial biogenesis in a rat coal workers' pneumoconiosis model through in vivo and in vitro experiments. Methods (1)n vivo: twelve SPF male SD rats (200-220 g) were randomized into a control group and a coal dust group (n=6 per group). After acclimatization, the coal dust group received 1 mL 50 mg·mL⁻¹ coal dust suspension via intratracheal instillation; the controls received saline. Lung tissues were harvested after two months for histopathology [HE, Masson, and transmission electron microscopy (TEM) ], protein and mRNA analysis, and mitochondrial DNA (mtDNA) quantification by quantitative real-time polymerase chain reaction (qPCR). (2) In vitro: rat lung type II epithelial cells (RLE-6TN) cells were exposed to coal dust (50, 100, 200, and 400 mg·L⁻¹, 24 h). CCK-8 assay determined optimal doses. Ultrastructural changes were analyzed by TEM. Cells were transfected with OE-PGC-1α (PGC-1α overexpression) or shRNA-PGC-1α plasmids (PGC-1α knockdown), and the transfection efficiency was determined by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR). The expression levels of alpah-smooth muscle actin (α-SMA), citrate synthase (CS), PGC-1α, NRF1, TFAM, and fibronectin (Fn) proteins and their corresponding mRNA were detected using Western blot and RT-qPCR, respectively. The relative content of mtDNA was determined by qPCR. Results In vivo: the control group lung samples exhibited soft, pink parenchyma, while the coal dust-exposed lungs showed blackened surfaces with soft texture. The histopathological evaluation revealed intact alveolar walls in the controls versus structural destruction, micro-nodules, and fibrotic areas in the coal dust group. After Masson staining, coal dust deposits were found surrounded by blue collagen fibers in the exposed lungs, but absent in the controls. The coal dust group displayed significant upregulation of fibrotic marker α-SMA and downregulation of mitochondrial biogenesis markers (CS, PGC-1α, NRF1, TFAM) and mtDNA compared to the controls (P<0.05). In vitro: coal dust exposure reduced cell density and induced morphological alterations. TEM revealed evenly distributed normal mitochondria in controls versus mitochondrial swelling, disrupted cristae, and reduced numbers in exposed cells. The mitochondrial biogenesis markers were elevated in the coal dust + OE-PGC-1α group compared to the coal dust + OE-NC group (P<0.05); in contrast, they were decreased in the coal dust + shRNA-PGC-1α group compared to the coal dust + shRNA-NC group (P<0.05). Compared to the control group, the expression levels of the fibrosis marker α-SMA mRNA and protein were increased in the coal dust group (P<0.05). Overexpression of PGC-1α reduced α-SMA expression, while downregulation of PGC-1α increased its expression (P<0.05). Conclusion Coal dust exposure induces mitochondrial dysfunction and pulmonary fibrosis in vivo and in vitro via the PGC-1α-NRF1-TFAM pathway dysregulation. Targeting this pathway may mitigate coal dust-induced fibrosis by restoring mitochondrial biogenesis.

[This corrects the article DOI: 10.1016/j.apsb.2022.05.019.].

[Objective] To study the molecular biological mechanism for a case of ABO blood group B subtype, and perform three-dimensional modeling of the mutant enzyme. [Methods] The ABO phenotype was identified by the tube method and microcolumn gel method; the ABO gene of the proband was detected by sequence-specific primer polymerase chain reaction (PCR-SSP), and the exon 6 and 7 of the ABO gene were sequenced and analyzed. Homologous modeling of Bw.03 glycosyltransferase (GT) was carried out by Modeller and analyzed by PyMOL2.5.0 software. [Results] The weakening B antigen was detected in the proband sample by forward typing, and anti-B antibody was detected by reverse typing. PCR-SSP detection showed B, O gene, and the sequencing results showed c.721 C>T mutation in exon 7 of the B gene, resulting in p. Arg 241 Trp. Compared with the wild type, the structure of Bw.03GT was partially changed, and the intermolecular force analysis showed that the original three hydrogen bonds at 241 position disappeared. [Conclusion] Blood group molecular biology examination is helpful for the accurate identification of ambiguous blood group. Homologous modeling more intuitively shows the key site for the weakening of Bw.03 GT activity. The intermolecular force analysis can explain the root cause of enzyme activity weakening.

Objective: To explore the impacts of coal mine dust on lung function in rats, so as to provide the basis for the early prevention and treatment of coal worker's pneumoconiosis. Methods: Seventy-two SPF-grade 8-week-old male Sprague-Dawley rats were randomly divided into the coal dust group, the coal-silica dust group, the silica dust group and the control group. The rats in the first three groups of rats were administered 1 mL corresponding dust suspension into the lungs using non-exposure tracheal instillation, while the rats in the control group were administered 1 mL normal saline. Respiratory rate (f), forced vital capacity (FVC), peak expiratory flow (PEF) and dynamic pulmonary compliance (Cdyn) were measured at 1, 3 and 6 months after dust exposure. Lung tissues were collected to measure reactive oxygen species (ROS) and adenosine triphosphate (ATP) levels using corresponding ELISA kits and ATP assay kits, respectively. The relative mRNA expressions of peroxisome proliferators-activated receptor gamma coactivator 1-alpha (PGC-1α) and mitochondrial transcription factor A (TFAM) were detected using real-time fluorescent quantitative polymerase chain reaction assay. The relative protein expressions of PGC-1α and TFAM were detected using Western blotting. Results: There was no interaction between dust type and exposure duration on f (P>0.05), but there were interactions on FVC, PEF and Cdyn (all P<0.05). Compared with the control group at 6 months after dust exposure, the f of the rats in the silica dust group were increased, while the FVC and PEF of the rats in the coal-silica dust and silica dust groups were decreased, and Cdyn of the rats in the coal dust, coal-silica dust and silica dust groups were decreased (all P<0.05). There were interactions between dust type and exposure duration on ROS and ATP levels, the relative mRNA and protein expressions of PGC-1α and TFAM (all P<0.05). Compared with the control group at 3 and 6 months after dust exposure, the ROS levels in the rats in the coal dust, coal-silica dust and silica dust groups were increased, while the ATP levels, the relative mRNA and protein expressions of PGC-1α and TFAM were decreased (all P<0.05). Conclusion The lung function impairment in rats caused by different types of coal mine dust is related to PGC-1α-mediated mitochondrial biogenesis dysfunction, which leads to increased ROS levels, decreased ATP and TFAM levels.

Objective:To identify factors influencing treatment-free remission (TFR) outcomes in children and adolescent patients with chronic myeloid leukemia (CML) after imatinib (IM) discontinuation.Methods:This multicenter retrospective study analyzed 36 children and adolescent patients with CML from eight hematology centers in China (December 1, 2016, to September 27, 2024) who discontinued IM therapy with documented post-cessation outcomes. Clinical characteristics and molecular response dynamics were assessed. Univariate analysis and multivariate Cox proportional hazards regression models were employed to assess factors associated with TFR outcomes.Results:A total of 36 patients were documented, comprising 17 males and 19 females. The median ages at CML diagnosis and IM discontinuation were 11 years ( IQR: 5,16) and 20 years ( IQR: 14,25), respectively. The median time from IM initiation to first deep molecular response (DMR) was 21 months ( IQR: 13, 38). Pre-discontinuation, patients received IM for a median duration of 96 months ( IQR: 84, 121) and maintained DMR for 74 months ( IQR: 63, 89). With a median post-discontinuation follow-up of 38 months ( IQR: 15, 68), cumulative TFR rates at 6, 12, 24, and 36 months were 74.1%, 60.7%, 60.7%, and 56.0%, respectively, generating an overall TFR rate of 58.3%. Fifteen patients lost major molecular response at a median of 5 months post-discontinuation ( IQR: 3, 11). All 15 patients resumed tyrosine kinase inhibitor therapy, comprising 13 who restarted IM and 2 who switched to dasatinib. By the last follow-up, 13 (86.7% ) patients regained DMR after a median treatment duration of 5 months ( IQR: 3, 17), and no disease progression occurred in any patient. Withdrawal syndrome occurred in 2 (5.6% ) patients. Univariate analysis revealed significantly higher TFR rates in patients with pre-discontinuation IM duration of ≥100 months vs <100 months (82.4% vs 36.8%, P=0.017) and pre-discontinuation DMR duration of ≥72 months vs <72 months (84.2% vs 29.4%, P=0.003). Multivariate Cox analysis identified pre-discontinuation DMR duration as an independent protective factor for TFR ( HR=5.419, 95% CI: 1.524–19.272, P=0.009) . Conclusion:DMR duration was identified as an independent protective factor influencing TFR outcomes in children and adolescent patients with CML after IM discontinuation. Patients who maintained DMR for ≥72 months before IM discontinuation demonstrated a significantly higher TFR rate.

Objective:To explore the effect of social cognition and interaction training (SCIT) combined with transcranial magnetic stimulation (TMS) on intrinsic motivation and social cognition in patients with schizophrenia.Methods:Forty-two stable schizophrenia patients were randomly divided into the SCIT + TMS group( n=22) and the SCIT group( n=20). All the subjects received 20 sessions of SCIT treatment, and the SCIT+ TMS group simultaneously received 15 sessions of intermittent theta burst stimulation(iTBS) over the left dorsolateral prefrontal cortex(DLPFC). All the subjects were assessed by intrinsic motivation inventory for schizophrenia research(IMI-SR), Chinese version of the ambiguous intentions hostility questionnaire(AIHQ-C), theory of mind-picture sequencing task(ToM-PST), mentalization scale (MentS), Chinese version of interpersonal reactivity index (IRI-C) and positive and negative syndrome scale (PANSS) before and after intervention. SPSS 26.0 software was used for data analysis.Wilcoxon signed-rank test was used for intra-group comparison before and after treatment, while Mann-Whitney U test and covariance analysis were used for inter-group comparison.Spearman correlation analysis and Logistic regression analyses were used to explore the association between the intrinsic motivation and social cognition. Results:There were no significant differences on IMI-SR scores before and after treatment between the two groups(all P>0.05). In the SCIT+ TMS group, the total score of hostility bias (HB), HB scores in ambiguous scenes, HB scores in intentional scenes, and aggressive bias (AB) scores in ambiguous scenes of AIHQ-C scale after treatment were lower than those befor treatment( Z=-2.044--3.112, all P<0.05), while the total score of ToM-PST(18.50(16.00, 21.00) vs 15.50(11.75, 18.00), Z=-2.598, P=0.009) and IRI-C imagination score (12.18±3.79, 14.41±4.73, t=-2.694, P=0.014) were higher than those before treatment.In the SCIT group, the total score of ToM-PST after treatment was higher than that before treatment(21.00(20.00, 22.00) vs 17.00(14.50, 20.75), Z=-2.518, P=0.012).There was no significant statistical difference in MentS scores between after treatment and before treatment ( P>0.05). The difference in AIHQ-C intentional scenario AB score before and after treatment was higher in the SCIT+ TMS group than in the SCIT group ( Z=-1.996, P=0.046), while there was no statistically significant difference in the difference before and after treatment in social cognitive scores between the two groups (all P>0.05).In the combined two samples, Spearman correlation analysis showed that the total score of IMI-SR before treatment was positively correlated with the primary belief score of ToM-PST understanding, reciprocity score, MentS total score, other person mentalization score, motivation mentalization score, IRI-C total score, viewpoint taking score, and empathy concern score after treatment( r=0.341-0.509, all P<0.05), while negatively correlated with AIHQ-C total score and factor scores ( r=-0.434--0.645, P<0.05).Logistic regression analysis showed that the total score of IMI-SR had negative impact on AIHQ-C total HB score( B=-0.047, OR=0.954, 95% CI=0.917-0.993).The value score had a positive impact on the total score of MentS ( B=0.143, OR=1.154, 95% CI=1.043-1.277), other person mentalization score( B=0.166, OR=1.181, 95% CI=1.058-1.318), motivation mentalization score( B=0.111, OR=1.117, 95% CI=1.021-1.223), IRI-C total score ( B=0.138, OR=1.148, 95% CI=1.038-1.270), and viewpoint taking score( B=0.194, OR=1.214, 95% CI=1.076-1.369). Interest score had a positive impact on IRI-C empathy concern score ( B=0.098, OR=1.103, 95% CI=0.998-1.218) and ToM-PST understanding primary belief score( B=0.130, OR=1.138, 95% CI=1.010-1.283) and reciprocity score( B=0.189, OR=1.208, 95% CI=1.057-1.380). Conclusion:The research results did not confirm the effect of TMS over the DLPFC on enhancing intrinsic motivation, as well as the synergistic effect of SCIT treatment on social cognition. But the correlation results indicates that improving schizophrenia patients' intrinsic motivation level in cognitive training is meaningful for promoting social cognition.

Objective:To evaluate the clinical performance of high-risk human papillomavirus (HR-HPV) genotyping in cervical cancer screening.Methods:Between June and July 2017, a prospective cervical cancer screening cohort was established in Xiaye Town, Jiyuan City, Henan Province, China by recruiting 3 254 women aged 21 to 64 years. At baseline screening, cervical exfoliated cell specimens were collected for HR-HPV genotyping and liquid-based cytology testing. Follow-ups were conducted over a 3-year period, with cytology testing in the first and second years and both HR-HPV genotyping and cytology testing in the third year. Women meeting the referral criteria were referred for colposcopy, with cervical biopsy and histopathological diagnosis performed as necessary. The endpoint was defined as cervical intraepithelial neoplasia grade 2 (CIN2) or higher confirmed by histopathological diagnosis. The sensitivity and specificity for detecting CIN2 or higher lesions of HR-HPV genotyping were calculated, as well as the cumulative risk of developing CIN2 or higher lesions over the 4-year study period in women with different baseline HR-HPV genotyping results.Results:A total of 2 741 women were included in the statistical analysis. Baseline HR-HPV genotyping detected 453 HR-HPV positive cases (16.53%), including 98 HPV 16/18 positive cases (3.58%) and 355 other HR-HPV positive cases (12.95%). During the 4-year period, 83 cases of CIN2 or higher were diagnosed. The sensitivity and specificity of baseline HR-HPV positivity for CIN2 or higher were 89.16% (95% CI: 80.66%-94.19%) and 85.74% (95% CI: 84.36%-87.02%), respectively. The corresponding rates for HPV 16/18 positivity were 43.37% (95% CI: 33.24%-54.09%) and 97.67% (95% CI: 97.02%-98.18%). The 4-year cumulative absolute risk of CIN2 or higher was highest in the HPV 16/18 positive group (36.73%, 95% CI: 27.85%-46.62%), followed by other HR-HPV positive groups (10.70%, 95% CI: 7.87%-14.38%), and the HR-HPV negative group was the lowest (0.39%, 95% CI: 0.19%-0.76%). Conclusions:HR-HPV genotyping testing exhibits high sensitivity and specificity for detecting CIN2 or higher lesions in cervical cancer screening. It also provides a scientific basis for stratifying the individual risk of developing CIN2 or higher lesions to guide subsequent management. Therefore, the HR-HPV genotyping testing can be considered as an effective method for cervical cancer screening.

The aim of this study was to investigate the mechanism of quercetin in inhibiting the fer-roptosis induced by zearalenone(ZEN)via mediating the nuclear factor erythroid-2-related factor 2(Nrf2)/glutathione peroxidase 4(GPX4)signaling pathway.IPEC-J2 cells were cultured in vitro and treated with ZEN(25 mg/L)and different concentrations of quercetin(10,20,40 μmol/L).Bi-ochemical methods were used to detect the levels of lactate dehydrogenase(LDH)in the cell cul-ture medium supernatant,total antioxidant capacity(T-AOC),superoxide dismutase(SOD),glu-tathione(GSH),and malondialdehyde(MDA).Fluorescence probes were used to detect the levels of Fe2+,reactive oxygen species(ROS),and lipid peroxidation.Western blot was performed to de-tect the expression levels of Nrf2,long chain acyl CoA synthetase 4(ACSL4),and GPX4.The IPEC-J2 cells were divided into the control group,ZEN group,quercetin group,and ML385(Nrf2 inhibitor)+quercetin group for further analysis.Except for the control group,the other groups were treated with ZEN in the prescence of quercetin and ML385.The changes of Nrf2/GPX4 path-way-related proteins and ferroptosis-related indexes(LDH,Fe2+,MDA,and GSH)were detected.Compared with the control group,IPEC-J2 cells in the ZEN group exhibited a decrease in cell via-bility,T-AOC,and GSH,SOD levels,Nrf2,and GPX4 protein expressions(P＜0.05),while LDH release rate,Fe2+and ROS,lipid peroxidation,MDA levels,and ACSL4 protein expression de-creased in the ZEN group(P＜0.05).Compared with ZEN group,the cell viability,the levels of T-AOC,SOD and GSH,the protein expression of Nrf2 and GPX4 in quercetin groups were increased(P＜0.05),while the LDH release rate,the levels of Fe2+,ROS,lipid peroxidation,and MDA as well as the protein expression of ACSL4 were decreased(P＜0.05).Compared with the quercetin group,the protein expression of Nrf2 and GPX4 and the level of GSH in ML385+quercetin group reduced(P＜0.05),the LDH release rate and the levels of Fe2+and MDA increased(P＜0.05).In summary,quercetin could inhibit ZEN-induced ferroptosis of IPEC-J2 cells,and its mechanism may be related to the induction of Nrf2/GPX4 signaling pathway.

Objective To explore the potential clinical value of the ratio of glycated albumin to albumin(GA/ALB)in the occurrence of heart failure(HF)among patients with coronary atherosclerotic heart disease(CHD).Methods A total of 337 CHD patients admitted to the Department of Cardiology in Shanxi Provincial People's Hospital from July 2023 to June 2024 were selected in this study.CHD patients were divided into HF group and non-HF group based on whether they progressed to HF.The clinical data and laboratory parame-ters of the two groups were compared.Restricted cubic spline curve was used to analyze the relationship be-tween GA/ALB levels and the risk of HF in CHD patients.Receiver operating characteristic curve was applied to evaluate the diagnostic efficacy of GA/ALB,GA,platelet to lymphocyte ratio(PLR),and monocyte to lym-phocyte ratio(MLR)in CHD patients with the occurrence of HF.Logistic regression was used to explore the relationship between serum GA/ALB levels and the risk of CHD patients occurrence of HF,and to analyze the degree of influence and stability of subgroup variables on results.Results There were statistically significant differences in GA/ALB,GA,PLR,MLR,and other indicators between the HF group and the non-HF group in CHD patients(P＜0.05).A non-linear relationship was observed between GA/ALB levels and the risk of HF in CHD patients.When the value of GA/ALB multiplied by 10 was less than 5.751,the risk of HF in CHD pa-tients increased with the increase of GA/ALB levels(P＜0.001).GA/ALB was an effective predictor for HF occurrence in CHD patients.Multivariable Logistic regression model showed that GA/ALB was an independ-ent risk factor for CHD patients with occurrence of HF.Subgroup analysis also confirmed the stability of GA/ALB in predicting the occurrence of HF in CHD patients.Conclusion GA/ALB is an independent risk factor for the occurrence of HF in CHD patients,and monitoring GA/ALB levels provides predictive value for the oc-currence of HF in these patients.