ObjectiveMultiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS); however, its underlying neurological pathogenic mechanisms remain incompletely understood. Endogenous formaldehyde (FA), a metabolic byproduct of methylation-demethylation cycles, has recently been implicated in neurotoxicity, oxidative damage, and cognitive impairment. This study aimed to investigate whether excessive FA contributes to myelin sheath demyelination in mice and to evaluate the protective effects and mechanisms of two FA-elimination strategies: sodium bisulfite (NaHSO₃), a classical FA scavenger, and polyethylene glycol-modified astaxanthin nanoparticles (PEG-ATX@NPs), a brain-targeted nano-antioxidant formulation. MethodsA chronic demyelination model was established by feeding female C57BL/6J mice a diet containing 0.2% cuprizone (CPZ) for four weeks, followed by a two-week intervention period. Eighty mice were randomly assigned to four groups: NS (normal saline), CPZ+NS, CPZ+NaHSO₃, and CPZ+PEG-ATX@NPs. Behavioral tests, including open-field, Y-maze, and pole-climbing assays, were conducted to assess locomotor activity, motor coordination, and working memory. FA levels in serum, corpus callosum, and spinal cord were measured using an Na-FA fluorescent probe and quantified via in vivo and ex vivo fluorescence imaging. Neuroinflammatory responses were evaluated by measuring TNF-α, IL-1β, and IL-6 levels using ELISA, while oxidative stress was assessed by reactive oxygen species (ROS) fluorescence intensity. Demyelination was examined via Luxol fast blue staining, and microglial activation was analyzed by Iba1 immunofluorescence. Correlation analyses were performed to explore relationships among FA levels, inflammatory cytokines, ROS intensity, and behavioral parameters. ResultsCompared with the NS group, mice in the CPZ+NS group exhibited significant weight loss, impaired motor coordination and memory, and markedly reduced myelin regeneration (P<0.05). FA levels and pro-inflammatory cytokines were significantly elevated in serum, corpus callosum, and spinal cord (P<0.05). FA-associated fluorescence in brain and spinal tissues, as well as ROS intensity across all tissues examined, also increased substantially (P<0.05). CPZ treatment induced pronounced microglial activation and severe demyelination in the corpus callosum (P<0.01). Both NaHSO₃ and PEG-ATX@NPs effectively reduced FA accumulation in the brain and spinal cord, attenuated demyelination, suppressed microglial activation, decreased inflammatory cytokine levels, and improved motor and cognitive performance. These results confirm that CPZ induced severe demyelination accompanied by oxidative stress, neuroinflammation, and abnormal FA accumulation. Following intervention with either NaHSO₃ or PEG-ATX@NPs, endogenous FA levels in the CNS were substantially reduced. Both treatments alleviated demyelination and significantly decreased the number of activated microglia. Levels of TNF-α, IL-1β, and IL-6 in serum, corpus callosum, and spinal cord were downregulated. Behavioral performance improved significantly, as evidenced by enhanced locomotor activity, better coordination, and improved memory function. These findings indicate that both FA-scavenging agents mitigate CPZ-induced biochemical and behavioral abnormalities. ConclusionThis study demonstrates that excessive endogenous FA is closely associated with cognitive impairment, inflammatory dysregulation, and demyelination in a CPZ-induced chronic demyelination mouse model. Clearing abnormally elevated FA effectively reduces neuroinflammation, suppresses microglial overactivation, decreases oxidative stress, and alleviates demyelination, ultimately improving motor and cognitive outcomes in mice. These results suggest that targeting endogenous FA represents a promising therapeutic strategy for MS and other demyelinating disorders. Further investigations are warranted to explore the long-term safety, dosage optimization, and molecular pathways involved in FA-mediated neurotoxicity.

ObjectiveMultiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system (CNS); however, its underlying neurological pathogenic mechanisms remain incompletely understood. Endogenous formaldehyde (FA), a metabolic byproduct of methylation-demethylation cycles, has recently been implicated in neurotoxicity, oxidative damage, and cognitive impairment. This study aimed to investigate whether excessive FA contributes to myelin sheath demyelination in mice and to evaluate the protective effects and mechanisms of two FA-elimination strategies: sodium bisulfite (NaHSO₃), a classical FA scavenger, and polyethylene glycol-modified astaxanthin nanoparticles (PEG-ATX@NPs), a brain-targeted nano-antioxidant formulation. MethodsA chronic demyelination model was established by feeding female C57BL/6J mice a diet containing 0.2% cuprizone (CPZ) for four weeks, followed by a two-week intervention period. Eighty mice were randomly assigned to four groups: NS (normal saline), CPZ+NS, CPZ+NaHSO₃, and CPZ+PEG-ATX@NPs. Behavioral tests, including open-field, Y-maze, and pole-climbing assays, were conducted to assess locomotor activity, motor coordination, and working memory. FA levels in serum, corpus callosum, and spinal cord were measured using an Na-FA fluorescent probe and quantified via in vivo and ex vivo fluorescence imaging. Neuroinflammatory responses were evaluated by measuring TNF-α, IL-1β, and IL-6 levels using ELISA, while oxidative stress was assessed by reactive oxygen species (ROS) fluorescence intensity. Demyelination was examined via Luxol fast blue staining, and microglial activation was analyzed by Iba1 immunofluorescence. Correlation analyses were performed to explore relationships among FA levels, inflammatory cytokines, ROS intensity, and behavioral parameters. ResultsCompared with the NS group, mice in the CPZ+NS group exhibited significant weight loss, impaired motor coordination and memory, and markedly reduced myelin regeneration (P<0.05). FA levels and pro-inflammatory cytokines were significantly elevated in serum, corpus callosum, and spinal cord (P<0.05). FA-associated fluorescence in brain and spinal tissues, as well as ROS intensity across all tissues examined, also increased substantially (P<0.05). CPZ treatment induced pronounced microglial activation and severe demyelination in the corpus callosum (P<0.01). Both NaHSO₃ and PEG-ATX@NPs effectively reduced FA accumulation in the brain and spinal cord, attenuated demyelination, suppressed microglial activation, decreased inflammatory cytokine levels, and improved motor and cognitive performance. These results confirm that CPZ induced severe demyelination accompanied by oxidative stress, neuroinflammation, and abnormal FA accumulation. Following intervention with either NaHSO₃ or PEG-ATX@NPs, endogenous FA levels in the CNS were substantially reduced. Both treatments alleviated demyelination and significantly decreased the number of activated microglia. Levels of TNF-α, IL-1β, and IL-6 in serum, corpus callosum, and spinal cord were downregulated. Behavioral performance improved significantly, as evidenced by enhanced locomotor activity, better coordination, and improved memory function. These findings indicate that both FA-scavenging agents mitigate CPZ-induced biochemical and behavioral abnormalities. ConclusionThis study demonstrates that excessive endogenous FA is closely associated with cognitive impairment, inflammatory dysregulation, and demyelination in a CPZ-induced chronic demyelination mouse model. Clearing abnormally elevated FA effectively reduces neuroinflammation, suppresses microglial overactivation, decreases oxidative stress, and alleviates demyelination, ultimately improving motor and cognitive outcomes in mice. These results suggest that targeting endogenous FA represents a promising therapeutic strategy for MS and other demyelinating disorders. Further investigations are warranted to explore the long-term safety, dosage optimization, and molecular pathways involved in FA-mediated neurotoxicity.

ObjectiveTo explore the mechanism by which Xianglian Huazhuo prescription ameliorates chronic atrophic gastritis （CAG） through regulating the Golgi protein 73 （GP73）/protein kinase R-like endoplasmic reticulum kinase （PERK）/activating transcription factor 4 （ATF4） signaling pathway and modulating endoplasmic reticulum stress （ERS）. MethodA mouse model of CAG was induced by multiple factors， including ranitidine， N-methyl-N′-nitro-N-nitrosoguanidine （MNNG）， and irregular feeding. The CAG mice were randomized into five groups： model， Morodan （2.0 g·kg^-1）， and high-dose， medium-dose， and low-dose （7.6， 3.8， 1.9 g·kg^-1， respectively） Xianglian Huazhuo prescription， with 10 mice in each group. At the same time， 10 mice in normal group were set up. The mice in the Morodan group and the high-dose， medium-dose， and low-dose groups of Xianglian Huazhuo prescription were administrated with corresponding agents by gavage， and those in the normal group and the model group were administrated with an equal volume of normal saline. All the mice were intervened once a day for 60 consecutive days. After the last administration， the overall morphological changes of the gastric tissue were observed. Hematoxylin-eosin （HE） staining and transmission electron microscopy （TEM） were used to evaluate the pathological morphology and the endoplasmic reticulum ultrastructure in the gastric tissue. The serum levels of pepsinogen Ⅰ （PGⅠ）， pepsinogen Ⅱ （PGⅡ）， gastrin-17 （G-17）， and GP73 were determined by enzyme-linked immunosorbent assay （ELISA）. The pepsinogen ratio （PGR， PGⅠ/PGⅡ） was calculated. The protein levels of GP73， PERK， phosphorylated （p）-PERK， glucose-regulated protein 78 （GRP78）， ATF4， CCAAT enhancer-binding protein homologous protein （CHOP）， cysteinyl aspartate-specific protease-12 （Caspase-12）， B-cell lymphoma-2 （Bcl-2）， and Bcl-2-associated X protein （Bax） were assessed by Western blot. The expression of GRP78 was detected by immunofluorescence （IF） assay， and the location of Bcl-2 and Bax by immunohistochemistry （IHC）. ResultsCompared with the normal group， the model group showed pale gastric mucosa with flattened folds and reduced and loosely arranged gastric mucosal glands， declined serum levels of PGI， PGR， G-17， and GP73 （P<0.01）. downregulated protein levels of GP73， p-PERK， ATF4， GRP78， CHOP， Caspase-12， and Bax in the gastric tissue， and upregulated protein level of Bcl-2 （P<0.01）. Compared with the model group， the Morodan group and each Xianglian Huazhuo prescription group exhibited red gastric mucosa with increased folds， alleviated pathological damage， swelling endoplasmic reticulum， elevated serum levels of PGI， G-17， and GP73 （P<0.05， P<0.01）， and upregulated protein levels of Caspase-12 and Bax and downregulated protein level of Bcl-2 in the gastric tissue （P<0.05， P<0.01）. The Morodan group and the high-dose and medium-dose Xianglian Huazhuo prescription groups exhibited increased serum level of PGR （P<0.05， P<0.01） and upregulated protein levels of GP73， p-PERK， ATF4， GRP78， and CHOP in the gastric tissue （P<0.05， P<0.01）. ConclusionXianglian Huazhuo prescription can activate the GP73/PERK/ATF4 signaling pathway and induce ERS-mediated apoptosis to alleviate the pathological damage of the gastric mucosa， thereby demonstrating a protective effect against CAG in mice.

ObjectiveTo explore the mechanism by which Xianglian Huazhuo prescription ameliorates chronic atrophic gastritis （CAG） through regulating the Golgi protein 73 （GP73）/protein kinase R-like endoplasmic reticulum kinase （PERK）/activating transcription factor 4 （ATF4） signaling pathway and modulating endoplasmic reticulum stress （ERS）. MethodA mouse model of CAG was induced by multiple factors， including ranitidine， N-methyl-N′-nitro-N-nitrosoguanidine （MNNG）， and irregular feeding. The CAG mice were randomized into five groups： model， Morodan （2.0 g·kg^-1）， and high-dose， medium-dose， and low-dose （7.6， 3.8， 1.9 g·kg^-1， respectively） Xianglian Huazhuo prescription， with 10 mice in each group. At the same time， 10 mice in normal group were set up. The mice in the Morodan group and the high-dose， medium-dose， and low-dose groups of Xianglian Huazhuo prescription were administrated with corresponding agents by gavage， and those in the normal group and the model group were administrated with an equal volume of normal saline. All the mice were intervened once a day for 60 consecutive days. After the last administration， the overall morphological changes of the gastric tissue were observed. Hematoxylin-eosin （HE） staining and transmission electron microscopy （TEM） were used to evaluate the pathological morphology and the endoplasmic reticulum ultrastructure in the gastric tissue. The serum levels of pepsinogen Ⅰ （PGⅠ）， pepsinogen Ⅱ （PGⅡ）， gastrin-17 （G-17）， and GP73 were determined by enzyme-linked immunosorbent assay （ELISA）. The pepsinogen ratio （PGR， PGⅠ/PGⅡ） was calculated. The protein levels of GP73， PERK， phosphorylated （p）-PERK， glucose-regulated protein 78 （GRP78）， ATF4， CCAAT enhancer-binding protein homologous protein （CHOP）， cysteinyl aspartate-specific protease-12 （Caspase-12）， B-cell lymphoma-2 （Bcl-2）， and Bcl-2-associated X protein （Bax） were assessed by Western blot. The expression of GRP78 was detected by immunofluorescence （IF） assay， and the location of Bcl-2 and Bax by immunohistochemistry （IHC）. ResultsCompared with the normal group， the model group showed pale gastric mucosa with flattened folds and reduced and loosely arranged gastric mucosal glands， declined serum levels of PGI， PGR， G-17， and GP73 （P<0.01）. downregulated protein levels of GP73， p-PERK， ATF4， GRP78， CHOP， Caspase-12， and Bax in the gastric tissue， and upregulated protein level of Bcl-2 （P<0.01）. Compared with the model group， the Morodan group and each Xianglian Huazhuo prescription group exhibited red gastric mucosa with increased folds， alleviated pathological damage， swelling endoplasmic reticulum， elevated serum levels of PGI， G-17， and GP73 （P<0.05， P<0.01）， and upregulated protein levels of Caspase-12 and Bax and downregulated protein level of Bcl-2 in the gastric tissue （P<0.05， P<0.01）. The Morodan group and the high-dose and medium-dose Xianglian Huazhuo prescription groups exhibited increased serum level of PGR （P<0.05， P<0.01） and upregulated protein levels of GP73， p-PERK， ATF4， GRP78， and CHOP in the gastric tissue （P<0.05， P<0.01）. ConclusionXianglian Huazhuo prescription can activate the GP73/PERK/ATF4 signaling pathway and induce ERS-mediated apoptosis to alleviate the pathological damage of the gastric mucosa， thereby demonstrating a protective effect against CAG in mice.

Debates persist regarding the efficacy and safety of azvudine, particularly its real-world outcomes. This study involved patients aged ≥60 years who were admitted to 25 hospitals in mainland China with confirmed SARS-CoV-2 infection between December 1, 2022, and February 28, 2023. Efficacy outcomes were all-cause mortality during hospitalization, the proportion of patients discharged with recovery, time to nucleic acid-negative conversion (T _NANC), time to symptom improvement (T _SI), and time of hospital stay (T _HS). Safety was also assessed. Among the 5884 participants identified, 1999 received azvudine, and 1999 matched controls were included after exclusion and propensity score matching. Azvudine recipients exhibited lower all-cause mortality compared with controls in the overall population (13.3% vs. 17.1%, RR, 0.78; 95% CI, 0.67-0.90; P = 0.001) and in the severe subgroup (25.7% vs. 33.7%; RR, 0.76; 95% CI, 0.66-0.88; P < 0.001). A higher proportion of patients discharged with recovery, and a shorter T _NANC were associated with azvudine recipients, especially in the severe subgroup. The incidence of adverse events in azvudine recipients was comparable to that in the control group (2.3% vs. 1.7%, P = 0.170). In conclusion, azvudine showed efficacy and safety in older patients hospitalized with COVID-19 during the SARS-CoV-2 omicron wave in China.

Three evaluation methods were recommended for the key properties of the intravascular catheter lubricating coating such as stability,lubricity and integrity,including insoluble particle test method,friction test procedure and appearance detection method.Fifteen batches of microcatheters produced by different manufacturers were selected for testing to clarify the three methods in test principle,step,result,characteristic.References were provided for the design,production,evaluation and regulation of intravascular catheters with lubricant coatings.[Chinese Medical Equipment Journal,2025,46(1):66-72]

OBJECTIVE To stimulate the debridement and dressing process under the approximately real clinical scene by fluorescence labeling and understand the contamination status of the operators' bodies and their surround-ings so as to improve the strategies.METHODS A total of 41 trainees were recruited from Enterostomal Therapist Nursing Education Program of Peking University School of Medicine and International School of Wound Thera-pists of Peking University First Hospital in 2023.The examination was designed by stimulating the debridement and dressing operations with fluorescence labeling,the orange was used to simulate the wound of the patients,and the pad towel was placed under the orange to represent the contaminated surroundings of the wound.A round le-sion area with diameter of 2 cm was uniformly marked on the surface of the orange peel by the operators,the trai-nees were asked to remove the lesion tissues and take dressings.The fluorescent powders were smeared evenly on the orange and pad towel before the examination,and no fluorescence labeling for the surroundings was guaranteed.The trainees were required to wear hats,masks,isolation gowns and gloves during the operations,and take off the gloves and trace the scope of fluorescent contamination with ultraviolet radiator after the examina-tion.RESULTS The contamination rate was 92.68％for the trainees' bodies,100.00％for their surroundings.The hands and forearms were the most severe contaminated body sites,and the contamination rates were 85.37％(35/41)and 34.15％(14/41),respectively.The downside of the pad towel was the most frequently contaminated area of the surroundings,with the proportion of 90.24％(37/41);the right side of the pad towel was the area with the contamination disseminated farthest,with the median distance of dissemination 13.50 cm.In addition,the dressing change carts of 75.61％(31/41)of the trainees were contaminated.CONCLUSIONS The operations of de-bridement and dressing change may lead to varying degrees of contamination of their bodies and surroundings.It is necessary to strengthen the hand hygiene and protective isolation during the process of dressing change and pay attention to the disinfection of the dressing change carts so as to minimize the risk of hospital-associated infec-tions.

Three evaluation methods were recommended for the key properties of the intravascular catheter lubricating coating such as stability,lubricity and integrity,including insoluble particle test method,friction test procedure and appearance detection method.Fifteen batches of microcatheters produced by different manufacturers were selected for testing to clarify the three methods in test principle,step,result,characteristic.References were provided for the design,production,evaluation and regulation of intravascular catheters with lubricant coatings.[Chinese Medical Equipment Journal,2025,46(1):66-72]

OBJECTIVE To stimulate the debridement and dressing process under the approximately real clinical scene by fluorescence labeling and understand the contamination status of the operators' bodies and their surround-ings so as to improve the strategies.METHODS A total of 41 trainees were recruited from Enterostomal Therapist Nursing Education Program of Peking University School of Medicine and International School of Wound Thera-pists of Peking University First Hospital in 2023.The examination was designed by stimulating the debridement and dressing operations with fluorescence labeling,the orange was used to simulate the wound of the patients,and the pad towel was placed under the orange to represent the contaminated surroundings of the wound.A round le-sion area with diameter of 2 cm was uniformly marked on the surface of the orange peel by the operators,the trai-nees were asked to remove the lesion tissues and take dressings.The fluorescent powders were smeared evenly on the orange and pad towel before the examination,and no fluorescence labeling for the surroundings was guaranteed.The trainees were required to wear hats,masks,isolation gowns and gloves during the operations,and take off the gloves and trace the scope of fluorescent contamination with ultraviolet radiator after the examina-tion.RESULTS The contamination rate was 92.68％for the trainees' bodies,100.00％for their surroundings.The hands and forearms were the most severe contaminated body sites,and the contamination rates were 85.37％(35/41)and 34.15％(14/41),respectively.The downside of the pad towel was the most frequently contaminated area of the surroundings,with the proportion of 90.24％(37/41);the right side of the pad towel was the area with the contamination disseminated farthest,with the median distance of dissemination 13.50 cm.In addition,the dressing change carts of 75.61％(31/41)of the trainees were contaminated.CONCLUSIONS The operations of de-bridement and dressing change may lead to varying degrees of contamination of their bodies and surroundings.It is necessary to strengthen the hand hygiene and protective isolation during the process of dressing change and pay attention to the disinfection of the dressing change carts so as to minimize the risk of hospital-associated infec-tions.

Objective To investigate the risk factors for bronchopulmonary dysplasia(BPD)in twin preterm infants with a gestational age of<34 weeks,and to provide a basis for early identification of BPD in twin preterm infants in clinical practice.Methods A retrospective analysis was performed for the twin preterm infants with a gestational age of<34 weeks who were admitted to 22 hospitals nationwide from January 2018 to December 2020.According to their conditions,they were divided into group A(both twins had BPD),group B(only one twin had BPD),and group C(neither twin had BPD).The risk factors for BPD in twin preterm infants were analyzed.Further analysis was conducted on group B to investigate the postnatal risk factors for BPD within twins.Results A total of 904 pairs of twins with a gestational age of<34 weeks were included in this study.The multivariate logistic regression analysis showed that compared with group C,birth weight discordance of>25%between the twins was an independent risk factor for BPD in one of the twins(OR=3.370,95%CI:1.500-7.568,P<0.05),and high gestational age at birth was a protective factor against BPD(P<0.05).The conditional logistic regression analysis of group B showed that small-for-gestational-age(SGA)birth was an independent risk factor for BPD in individual twins(OR=5.017,95%CI:1.040-24.190,P<0.05).Conclusions The development of BPD in twin preterm infants is associated with gestational age,birth weight discordance between the twins,and SGA birth.