BACKGROUND:Autophagy,as a key regulatory mechanism of cell development,plays an important role in different stages of embryonic development.The mechanism of how autophagy regulates embryonic development through histone modifications is currently unclear.OBJECTIVE:To investigate the effect of autophagy on trimethylation of lysine 4 on histone H3(H3K4me3)modification in embryos and its effect on embryonic development.METHODS:Mouse fertilized eggs were divided into control and autophagy inhibitor-treated groups(chloroquine phosphate-treated group and 3-methyladenine-treated group),and cultured in vitro to different periods of time,and were then classified as early 2-cell embryos,middle 2-cell embryos,late 2-cell embryos,4-cell embryos,8-cell embryos,morula stage,and blastocyst stage.Levels of reactive oxygen species,autophagy marker proteins LC3B and P62,DNA loss marker γH2AX,and H3K4me3 were analyzed by immunofluorescence assay in late 2-cell embryos of each group.Changes in H3K4me3 modification in late 2-cell embryos of each group were detected by CUT&Tag.RESULTS AND CONCLUSION:(1)Autophagy inhibition caused embryo development arrest.(2)There was no significant difference in reactive oxygen species and γH2AX between the autophagy inhibitor-treated groups and control group.(3)H3K4me3 levels were significantly elevated in the autophagy inhibitor-treated group compared with the control group.(4)CUT&Tag results showed a significantly increased H3K4me3 peaks on the proximal promoter region of the genes after autophagy inhibition and an increase of H3K4me3-specific modification genes.These findings suggest that autophagy may affect embryonic development by regulating the level of H3K4me3 modification.

Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe²⁺), whereas clMagR favors ferric iron (Fe³⁺) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe²⁺-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe²⁺/Fe³⁺ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.

Objective Magnetoreception, the remarkable ability of diverse animals to sense and utilize the geomagnetic field for orientation and navigation, remains a molecularly unresolved mystery in sensory biology. The putative magnetoreceptor (MagR, previously known as IscA1) is a highly conserved iron-sulfur protein implicated in both magnetoreception and iron metabolism; however, the functional diversity among its cross-species homologs remains poorly understood. Cellular morphology is a key genetically determined trait that can be altered through genetic or environmental modifications—a process known as cell morphology engineering. Constructing engineered cells with specific morphological features and magnetic sensitivity to achieve remote, non-invasive magnetic modulation represents a crucial goal in this field with significant application potential. Therefore, this study aims to systematically investigate the effects of MagR heterologous expression on bacterial morphology and magnetic sensing capabilities, screen for MagR-based magnetically sensitive morphology engineering pathways, and reveal the underlying molecular mechanisms. Methods We systematically screened 28 MagR homologous genes from diverse prokaryotic and animal taxa to evaluate their expression and corresponding phenotypic effects in Escherichia coli (E. coli). To compare the differential magnetic responses among bacteria expressing various recombinant MagR proteins, we utilized high-throughput automated bright-field microscopic imaging and scanning electron microscopy (SEM). Furthermore, comprehensive biochemical and biophysical characterizations of iron and iron-sulfur cluster binding were performed using Ferrozine colorimetric assays, electron paramagnetic resonance (EPR) spectroscopy, ultraviolet-visible (UV-Vis) absorption, and circular dichroism (CD) spectroscopy. Additionally, 100 mT static magnetic field (SMF) exposure experiments were conducted to assess magnetically tunable phenotypes, while the intrinsic magnetic properties of purified MagR proteins were directly measured using a superconducting quantum interference device (SQUID) magnetometer. Results Our results demonstrated that the heterologous expression of MagR homologs induced varying degrees of bacterial filamentation. From this comprehensive screen, two distinct morphological patterns were identified: hydra (Hydra vulgaris) MagR (hyMagR) promoted uniform cell elongation and filamentation, exhibiting robust magnetic sensitivity manifested as significantly enhanced filamentation under the 100 mT SMF. In contrast, pigeon (Columba livia) MagR (clMagR) induced only low-frequency, extreme filamentation (sporadically exceeding 80 μm) with a relatively weaker magnetic morphological response. Mechanistically, our data unambiguously proved that these phenotypic differences are primarily driven by distinct iron redox preferences rather than total cellular iron accumulation. Specifically, hyMagR preferentially binds ferrous iron (Fe²⁺), whereas clMagR favors ferric iron (Fe³⁺) and forms more stable iron-sulfur clusters. Intriguingly, although SQUID magnetometry showed that purified clMagR exhibited approximately five-fold higher mass magnetic susceptibility than hyMagR, its cellular magnetic response was weaker. We hypothesize that the Fe²⁺-preferred intracellular environment associated with hyMagR overexpression primes the cell for enhanced generation of reactive oxygen species (ROS) via the Fenton reaction. Exposure to an SMF synergizes with this primed redox state, triggering the bacterial SOS response and upregulating cell division inhibitors to efficiently induce uniform filamentation. Conclusion Our findings identify the Fe²⁺/Fe³⁺ redox state as a critical determinant of MagR-mediated morphological remodeling and magnetic responsiveness. This discovery suggests a potential strategy for engineering magnetically responsive cellular systems for synthetic biology applications, and provides a plausible framework, which potentially combines intrinsic protein magnetism with redox-state modulation, for further investigating the evolutionary mechanisms of MagR-mediated magnetoreception.

[摘 要] 目的：探讨复发/转移性鼻咽癌（NPC）接受含PD-1单抗免疫治疗的临床特征和预后影响因素。方法：回顾性分析2019年3月至2024年7月期间南部战区总医院确诊的95例NPC患者的临床资料和外周血生化及免疫学指标。预后分析采用Kaplan-Meier曲线，组间比较使用Log-rank检验，采用Cox比例风险模型进行单因素和多因素分析。结果：95例患者中男性81例，女性14例，中位年龄49.72岁（16~74岁），Ⅳ期91例（95.79%），所有患者均采用免疫治疗，联合或不联合化疗方案治疗，中位无进展生存期（mPFS）为10.5个月，客观缓解率（ORR）70.53%，疾病控制率（DCR）89.47%，接受含铂治疗方案患者PFS相对更长，且差异有统计学意义。紫杉醇 + 顺铂 + 氟尿嘧啶（TPF）对比吉西他滨 + 顺铂（GP）和紫杉醇 + 顺铂（TP）显示出更长的PFS，但差异无统计学意义。不同PD-1单抗治疗组间的PFS未显示出有统计学意义的差异。单因素及多因素Cox回归分析结果显示，肿瘤复发状态、初始血浆EBV感染状态、治疗周期数、基线外周血SII是复发/转移性NPC患者接受PD-1抑制剂治疗疗效预测的独立相关因素（均P < 0.05），并且非复发患者、初始血浆EBV DNA阳性、接受 ≥ 4治疗周期、基线外周血SII < 772.81的患者接受PD-1抑制剂治疗预后相对更好。结论：在接受PD-1抑制剂治疗的复发/转移性NPC患者中，非复发患者、初始血浆EBV DNA阳性、≥ 4治疗周期且外周血SII < 772.81者PFS相对更长，可早期识别免疫治疗效果不佳患者并精准干预。

BACKGROUND:Autophagy,as a key regulatory mechanism of cell development,plays an important role in different stages of embryonic development.The mechanism of how autophagy regulates embryonic development through histone modifications is currently unclear.OBJECTIVE:To investigate the effect of autophagy on trimethylation of lysine 4 on histone H3(H3K4me3)modification in embryos and its effect on embryonic development.METHODS:Mouse fertilized eggs were divided into control and autophagy inhibitor-treated groups(chloroquine phosphate-treated group and 3-methyladenine-treated group),and cultured in vitro to different periods of time,and were then classified as early 2-cell embryos,middle 2-cell embryos,late 2-cell embryos,4-cell embryos,8-cell embryos,morula stage,and blastocyst stage.Levels of reactive oxygen species,autophagy marker proteins LC3B and P62,DNA loss marker γH2AX,and H3K4me3 were analyzed by immunofluorescence assay in late 2-cell embryos of each group.Changes in H3K4me3 modification in late 2-cell embryos of each group were detected by CUT&Tag.RESULTS AND CONCLUSION:(1)Autophagy inhibition caused embryo development arrest.(2)There was no significant difference in reactive oxygen species and γH2AX between the autophagy inhibitor-treated groups and control group.(3)H3K4me3 levels were significantly elevated in the autophagy inhibitor-treated group compared with the control group.(4)CUT&Tag results showed a significantly increased H3K4me3 peaks on the proximal promoter region of the genes after autophagy inhibition and an increase of H3K4me3-specific modification genes.These findings suggest that autophagy may affect embryonic development by regulating the level of H3K4me3 modification.

Objective To investigate the correlation between skeletal muscle mass index(ASMI)and islet β cell reserve function in patients with newly diagnosed type 2 diabetes mellitus(T2DM).Methods A total of 100 patients with newly diagnosed T2DM were included in this study.All the patients were admitted to the Department of Endocrinology in the First People's Hospital of Yinchuan between June 2022 and November 2023.They were divided into two groups according to their skeletal muscle mass index(ASMI):patients with T2DM accompanied by sarcopenia(Sar,n=50)group,and patients with simple T2DM(T2DM,n=50)group.Additionally,a control(NC)group consisting of 50 healthy participants was selected.Fasting C-peptide levels,liver and kidney function,blood lipid profiles,and other indicators were assessed in all the individuals.The correlation between ASMI and other indicators was analyzed,and the influencing factors for ASMI and T2DM combined with sarcopenia were analyzed respectively.Results The levels of HbA1c,FPG,and TG were higher,while FC-P and Scr levels were lower in the T2DM group and Sar group compared with the NC group(P<0.05).FPG was higher,while ASMI,FC-P,BMI were lower in the Sar group than in the T2DM group(P<0.05).Spearman correlation analysis revealed a negative correlation between ASMI and FPG and HbA1c(P<0.05),whereas a positive correlation was observed with BMI,ALT,Scr,SUA and FC-P(P<0.05).Multiple linear regression analysis indicated that BMI,HbA1c and FC-P were influencing factors for ASMI(P<0.05).Furthermore,logistic regression analysis demonstrated that BMI,HbA1c,FC-P were influencing factors for T2DM with sarcopenia(P<0.05).Conclusions The level of ASMI may be related to the reserve function of islet β cells.

The advantages of deep learning(DL)over the traditional imaging evaluation methods were introduced for tumor prognosis prediction and efficacy assessment.The research progress of DL applied in prognosis and efficacy prediction of head and neck squamous cell carcinoma was reviewed in terms of survival prediction,local recurrence and distant metastasis,cervical lymph node metastasis,therapeutic efficacy and molecular markers of tumors.The defficiencies of DL for prognosis and efficacy prediction of head and neck squamous cell carcinoma were explored,and the future research directions were envisioned.[Chinese Medical Equipment Journal,2025,46(6):97-104]

This study aims to evaluate the preventive effect of the exogenous protein chIFN-γ-chCD154 against Salmonella typhimurium(S.typhimurium)infection in White Leghorn chick-ens,and the potential mechanism.In this study,Escherichia coli was used to express the proteins chIFN-γ,chCD154 and chIFN-γ-chCD154.Before S.typhimurium infection,the White Leghorn chickens were pre-immunized via drinking water for three consecutive days,and infected with S.typhimurium by gavage.The results from Western blot,quantitative real-time PCR(qRT-PCR)analysis and histopathology analysis showed that compared to chIFN-γ and chCD154,chIFN-γ-chCD154 pre-treatment could synergistically increase the survival rate of infected chickens,reduce the bacterial load in the liver and cecum,and attenuate the pathological damage of liver and cecum.Moreover,chIFN-γ-chCD154 significantly decreased the mRNA expression of Toll-like receptor-4(TLR-4)and myeloid differentiation primary response gene 88(MyD88)in the cecum,and then inhibited the mRNA expression of NF-κB and pro-inflammatory cytokines(TNF-α and IL-6),and maintained the integrity of the intestinal tight junction proteins(zo-1,claudin-1,occlu-din).Compared with single protein pretreatment,chIFN-γ-chCD154 pretreatment significantly up-regulated the mRNA expression of the genes related to the vitamin D(VD)pathway(cyp27b1,VD receptor VDR,antimicrobial peptide AvBD7 and cathelicidin-b1)in S.typhimurium-infected peripheral blood mononuclear cells(PBMCs).The results of colony counting showed that the num-ber of S.typhimurium in the chIFN-γ-chCD154 group were the lowest.Also,chIFN-γ-chCD154 could up-regulate the relative abundance of beneficial bacteria such as Blautia,Ruminococcus,En-terococcus and Faecalibacterium,while down-regulate the relative abundance of harmful bacteria such as Staphylococcaceae in the cecum and improve the intestinal dysbiosis.In conclusion,chIFN-γ-chCD154 could activate the VD-antimicrobial peptide pathway and inhibit the TLR-4/MyD88/NF-κB inflammatory signaling pathway in S.typhimurium-infected chickens,which significantly improve the intestinal barrier function,reduce the inflammatory damage of liver and cecum,im-prove the structure of cecum microbial,promote the health of intestinal tract,and provide theoreti-cal basis for the development of chIFN-γ-chCD154 as a safe and effective alternative antibiotic.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.