Neurocritical care involves complex pathophysiological mechanisms, and its incidence is higher, injuries are more severe, and treatment is more challenging in high-altitude environments. This consensus, based on the latest domestic and international evidence-based medical data, establishes a standardized, goal-oriented framework for neurocritical care management applicable in high-altitude regions and nationwide. The consensus was developed following international standards for evidence quality assessment and underwent two rounds of Delphi expert consultation, resulting in 32 recommendation statements covering three parts: management systems, monitoring and assessment, and core strategies. Key updates include: advocating for the establishment of independent neurocritical care units and implementing precise tiered diagnosis and treatment based on the "Five Differences in Critical Care" concept; constructing a "trinity" multimodal brain monitoring system centered on cerebral blood flow, cerebral oxygenation, and brain function, emphasizing routine bedside transcranial Doppler ultrasound, cerebral oximetry, and continuous electroencephalography monitoring; shifting management strategies from mild hypothermia therapy to targeted temperature management, and defining the "446" target management pathway for the supercritical stage; emphasizing the assessment of static and dynamic cerebrovascular autoregulation functions through multimodal methods to achieve individualized optimal mean arterial pressure management; elevating cerebrospinal fluid management goals to the level of "glymphatic system" function maintenance; implementing a multidisciplinary collaborative, whole-process management model focusing on patients' long-term neurological functional outcomes; de-escalation criteria include multidimensional indicators such as recovery of brain structure, restoration of cerebrovascular autoregulation, improvement in cerebrospinal fluid dynamics, and reduction in biomarker levels; and integrating cutting-edge technologies like artificial intelligence into post-critical care management and rehabilitation planning. This consensus systematically integrates the entire process of neurocritical care management, reflecting the modern connotation of goal-oriented, dynamic, and multimodal integration in neurocritical care medicine. It aims to adapt to new trends such as deepening understanding of pathophysiological mechanisms, the integration of medicine and engineering, and the empowerment of artificial intelligence, thereby further advancing the discipline of critical care medicine.

ObjectiveTo explore the effects of astragalin （AST） on autophagy and apoptosis of astrocytes in the L_4-5 dorsal horn of the spinal cord in mice with inflammatory pain induced by complete Freund's adjuvant （CFA）. MethodsTwenty-four male C57BL/6 mice， aged six months， were randomly assigned to four groups： control group， saline group， CFA model group， and CFA+AST group， six mice in each group. The inflammatory pain model was established by injection of 10 µL CFA into the right lateral malleolus fossa. The saline group were injected with an equal amount of normal saline at the same site. The inflammatory pain mice in CFA+AST group were further treated with AST （60 mg/kg） intraperitoneally once a day for 21 consecutive days. Multiplex immunofluorescence staining was used to detect the coexpression of autophagy-related factors including ATG 12 and Beclin-1， apoptosis-related factors including Cleaved-Caspase3 and Caspase9， and the astrocyte marker such as GFAP in the L_4-5 spinal dorsal horn of the mice in each group. Western blot was used to examine the protein expression levels of autophagy-related proteins（ATG12， Beclin-1） and apoptosis-related proteins（Caspase 3， Caspase 9） in the L_4-5 spinal dorsal horn of mice. ResultsImmunofluorescent staining showed that in the L_4-5 dorsal horn of the spinal cord， the fluorescence intensity of ATG12 （P<0.000 1） and Beclin-1 （P<0.000 1） was significantly increased， while that of Cleaved-Caspase 3 （P<0.001） and Caspase 9 （P<0.000 1） was decreased in the CFA+AST group when compared to the CFA model group. Furthermore， AST could inhibit the activation of astrocytes. Western blot further confirmed that AST significantly upregulated the expression of ATG12 （P<0.000 1） and Beclin-1 （P<0.000 1） in the L_4-5 spinal cord of CFA mice， and downregulated the expression of Caspase 3 （P<0.01） and Caspase 9 （P<0.001）. ConclusionsAST promotes autophagy of astrocytes and inhibits their apoptosis in the L_4-5 spinal dorsal horn of CFA mice.

ObjectiveTo investigate the distribution patterns of hepatitis C virus (HCV) genotypes and their clinical characteristics in Qinghai Province, and to provide a theoretical basis for the elimination of hepatitis C in this region. MethodsA total of 527 hepatitis C patients from Qinghai Provincial Infectious Diseases Hospital from August 2023 to August 2024 were selected as the research subjects. Polymerase chain reaction (PCR) sequencing was used to determine the HCV genotypes of the hepatitis C patients, and the distribution patterns of HCV genotypes and the clinical characteristics of different genotypes in this region were observed. ResultsThe 527 hepatitis C patients were mainly distributed in Xining City and Haidong City, with the majority being male patients aged between 48 and <60 years. A total of 4 genotypes and7 subtypes were found, with genotype 2 being the most prevalent one (219 cases, 41.56%), followed by genotype 3 (173 cases, 32.83%),genotype 1 (131 cases, 24.86%) and genotype 6 (6 cases, 0.76%). There were statistically significant differences in gender, age, disease progression, population classification, residential address, transmission route, and liver inflammation indicators among different HCV subtypes (all P<0.05). Genotype 1 and genotype 2 accounted for a higher proportion in chronic hepatitis C patients under 40 years old, females, and transmitted through blood transfusions and invasive procedures, while genotype 3 were more common in male patients, aged ≥40 years old, those infected through intravenous drug use, and those were prone to progress to liver cirrhosis (mainly subtype 3b). Farmers, houseworkers and unemployed people were the main population groups in all genotypes. Compared with other genotypes, genotype 3 had higher levels of aspartate aminotransferase and alpha-fetoprotein and lower platelet counts, suggesting that the severity of the disease was related to different genotypes. ConclusionGenotype 2 and genotype 3 are the main types in Qinghai Province. The composition ratio of genotype 3, which is mainly transmitted through intravenous drug use, is increasing and more likely to progress to liver cirrhosis. This highlights the need to focus on the prevention, treatment and management of genotype 3.

OBJECTIVE: The investigation of the correlation between ecological factors and the genetic characteristics or metabolites of plants offers valuable insights into the regional causes of genetic and metabolic diversity. Here, Gastrodia elata, a medicinal plant, is employed as a model to explore the environmental factors that influence its genetic characteristics and metabolic accumulations. METHODS: A total of 23 G. elata populations from six cultispecies and 11 cultivated regions were selected based on the predictions of the global geographic information system. The genetic characteristics of these populations were evaluated using highly polymorphic simple sequence repeat markers. Additionally, the metabolic accumulations and antioxidant capacity of mature tubers were measured employing colorimetry and high performance liquid chromatography (HPLC). Ecological data of each region were obtained from the WorldClim-global climate database and harmonized world soil database. To assess the influence of ecological factors on the genetic characteristics and metabolic profiles of G. elata, Pearson's correlation analysis was conducted. RESULTS: Genetic variation among G. elata populations exceeded that within populations. Genetic diverisity, distance and structure manifested regional and species-specific patterns. Metabolic profiling and antioxidant capacity exhibited regional variations. Notably, the Lueyang region demonstrated that a content range of total polysaccharide, total protein, and phenolic glycosides was 9.34%-189.67% higher than the average. Similarly, in the Hubei region, total phenolic content, p-hydroxybenzyl alcohol content, and antioxidant indicators were observed to be higher than the average levels, by 106.57%, 136.47% and 12.50%-91.14%, respectively. Furthermore, ecological factors had a significant comprehensive impact on G. elata genetic characteristics (r > 0.256 and P < 0.05). Multivariate metabolite accumulations in G. elata were influenced by dominant ecological factors. Temperature notably impacted the accumulation of total protein (|r| > 0.528 and P < 0.05). Moisture, encompassing precipitation and soil content, significantly affected the production of phenolic glycosides (|r| > 0.503 and P < 0.05). CONCLUSION The genetic characteristics of G. elata manifested regional and species-specific patterns, with the metabolic accumulations and antioxidant capacity of mature tubers exhibited regional variations. Specifically, multivariate ecological factors comprehensively influenced genetic characteristics. Temperature and moisture played pivotal roles in regulating the accumulations of proteins and phenolic glycosides, respectively. These findings underscore the significant impact of ecological factors on the shaping of G. elata, highlighting their crucial role in enhancing the quality of Chinese medicinal materials.

ObjectiveTo investigate the potential value of thyroid hormones in cerebrospinal fluid in predicting autism-like behaviors induced by hypothyroidism in pregnant rats. MethodsTwelve pregnant Wistar rats were randomly divided into a control group and a hypothyroidism group （hypothyroidism model group）. Offspring from both groups had serum and cerebrospinal fluid levels of thyroid-stimulating hormone （TSH）， total triiodothyronine （TT3）， total thyroxine （TT4）， free triiodothyronine （FT3）， and free thyroxine （FT4） levels in serum and cerebrospinal fluid. Ultrasonic vocalization tests were conducted on postnatal day 2 （P2）， day 7 （P7）， and day 14 （P14）， while behavioral tests using the three-box social interaction test were performed on day 21（P21）. ResultsCompared with the control group， free T4 （FT4） levels in the cerebrospinal fluid of the hypothyroidism group were significantly reduced during the developmental period （P0-P21； P2： P<0.05； P7： P<0.05； P14： P<0.01； P21： P<0.01）， with no statistical difference between the two groups only at P0 （P>0.05）. In the ultrasonic vocalization （USV） tests， the number and duration of USVs in offsprings from the hypothyroidism group were significantly reduced compared with those of the control group on P2， P7 and P14： for USV counts （P2： P<0.05； P7： P<0.001； P14： P<0.01）； for USV duration （P2： P<0.05； P7： P<0.001； P14： P<0.001）. In the three-box social tests， offsprings of the hypothyroidism group showed significantly reduced sniffing time with unfamiliar rats at P21 compared to the control group （all P<0.001）. The FT4 levels in cerebrospinal fluid had a significantly positive correlation with USV counts （P7： r=0.883， P<0.05； P14： r=0.902， P<0.05） and sniffing time with unfamiliar rats （r=0.814， P<0.01）. ConclusionMeasuring free T4 in cerebrospinal fluid can predict autism-like behaviors in offsprings of rats induced by hypothyroidism during pregnancy.

ObjectiveTo investigate the role and mechanism of total saponins of Dioscorea （TSD） in mitigating nonalcoholic steatohepatitis （NASH） in mice. MethodForty-eight C57BL/6J mice were randomized into a normal group and a modeling group. The mice for modeling were fed with a high-fat and high-cholesterol diet + 20% fructose solution for 16 weeks and randomized into model， atorvastatin （4 mg·kg^-1·d^-1）， and high-， medium-， and low-dose （200， 60， and 20 mg·kg^-1·d^-1） TSD groups. The mice were administrated with corresponding doses of drugs by gavage for 8 weeks. The mouse activity， liver index， levels of total cholesterol （TC）， triglycerides （TG）， and free fatty acids （FFAs） in the liver， and levels of TC， TG， aspartate aminotransferase （AST）， alanine aminotransferase （ALT）， γ-glutamyl transferase （GGT）， interleukin-1β （IL-1β）， and tumor necrosis factor-α （TNF-α） in the serum were measured. Hematoxylin-eosin staining， Masson staining， oil red O staining， and transmission electron microscopy were employed to observe the pathological changes， lipid accumulation， and morphological changes of liver ultrastructure. Western blot was employed to determine the protein levels of AMP-activated protein kinase （AMPK）， sterol regulatory element-binding protein-1c （SREBP-1c）， acetyl-CoA carboxylase （ACC）， and phosphorylated ACC （p-ACC） in the liver tissue. ResultCompared with the normal group, the activity of mice in the model group decreased(P<0.05， P<0.01), the levels of TC, TG, FFA and serum TC, TG, ALT, AST, GGT, IL-1β and TNF-α, liver coefficient and liver pathology scores were significantly increased, the expression of p-AMPK/AMPK and p-ACC proteins in liver tissues was significantly reduced, and the expressions of SREBP-1c and ACC proteins were significantly increased (P<0.01). Compared with the model group， atorvastatin increased the mouse activity （P<0.05）， while each dose of TSD caused no significant changed in the mouse activity. The levels of TC, TG, FFA in liver and serum TC, TG, ALT, AST, GGT, IL-1β, TNF-α, liver coefficient and liver pathological score in TSD and atorvastatin groups were significantly decreased, and the expressions of p-AMPK/AMPK and p-ACC in liver tissue were significantly increased. The expressions of SREBP-1c and ACC were significantly decreased (P<0.05,P<0.01). ConclusionTSD may alleviate NASH in mice by regulating the AMPK/SREBP-1c/ACC signaling pathway to reduce lipid synthesis.

Background::Heterotaxy (HTX) is a thoracoabdominal organ anomaly syndrome and commonly accompanied by congenital heart disease (CHD). The aim of this study was to analyze rare copy number variations (CNVs) in a HTX/CHD cohort and to examine the potential mechanisms contributing to HTX/CHD.Methods::Chromosome microarray analysis was used to identify rare CNVs in a cohort of 120 unrelated HTX/CHD patients, and available samples from parents were used to confirm the inheritance pattern. Potential candidate genes in CNVs region were prioritized via the DECIPHER database, and PNPLA4 was identified as the leading candidate gene. To validate, we generated PNPLA4-overexpressing human induced pluripotent stem cell lines as well as pnpla4-overexpressing zebrafish model, followed by a series of transcriptomic, biochemical and cellular analyses. Results::Seventeen rare CNVs were identified in 15 of the 120 HTX/CHD patients (12.5%). Xp22.31 duplication was one of the inherited CNVs identified in this HTX/CHD cohort, and PNPLA4 in the Xp22.31 was a candidate gene associated with HTX/CHD. PNPLA4 is expressed in the lateral plate mesoderm, which is known to be critical for left/right embryonic patterning as well as cardiomyocyte differentiation, and in the neural crest cell lineage. Through a series of in vivo and in vitro analyses at the molecular and cellular levels, we revealed that the biological function of PNPLA4 is importantly involved in the primary cilia formation and function via its regulation of energy metabolism and mitochondria-mediated ATP production. Conclusions::Our findings demonstrated a significant association between CNVs and HTX/CHD. Our data strongly suggested that an increased genetic dose of PNPLA4 due to Xp22.31 duplication is a disease-causing risk factor for HTX/CHD.

Objective:To discuss the effect of microRNA(miR)-30c-5p on the proliferation,migration,and invasion of the human prostate cancer cells(LNCap),and to clarify its possible mechanism.Methods:The LNCap cells were divided into LNCap group(without plasmid transfection),miR-30c-5p mimic group(transfected with miR-30c-5p mimic),mimic NC group(transfected with miR-30c-5p mimic NC),sh-DNA damage inducible transcript 4(DDIT4)group(transfected with sh-DDIT4),sh-NC group(transfected with sh-DDIT4 NC),miR-30c-5p mimic+pc-DNA3.1-NC group(co-transfected with miR-30c-5p mimic and pc-DNA3.1 empty vector),and miR-30c-5p mimic+pc-DNA3.1-DDIT4 group(co-transfected with miR-30c-5p mimic and pc-DNA3.1-DDIT4 over-expression plasmid).The RWPE-1 cells were cultured normally.Real-time fluorescence quantitative PCR(RT-qPCR)method was used to detect the expression levels of miR-30c-5p and DDIT4 mRNA in the cells in various groups;Western blotting method was used to detect the expression levels of DDIT4 protein in the cells in various groups;CCK-8 method was used to detect the proliferation rates of the LNCap cells in various groups;Transwell assay was used to detect the numbers of the invasion LNCap cells in various groups;Scratch assay was used to detect the scratch healing rates of LNCap cells in various groups;dual-luciferase reporter assay was used to detect the targeting relationship between miR-30c-5p and DDIT4.In the in vivo tumor formation experiment,18 male BALB/c nude mice were divided randomly into blank group,agomiR-NC group(transfected with agomiR-30c-5p NC),and agomiR-30c-5p group(transfected with agomiR-30c-5p);there were six mice in each group.The mice in agomiR-NC group and agomiR-30c-5p group were subcutaneously injected with LNCap cells,while the mice in blank group were given an equal volume of physiological saline.The volumes of tumor of the mice in various groups were detected.HE staining was used to observe the morphology of prostate cancer tissue the mice of in various groups;RT-qPCR method and immunofluorescence staining were used to detect the expression levels of miR-30c-5p and DDIT4 mRNA and the fluorescence intensities of DDIT4 protein in prostate cancer tissue of the mice in various groups.Results:The In vitro prostate cancer cell experiment results showed that compared with RWPE-1 cells,the expression level of miR-30c-5p in the prostate cancer LNCap cells was decreased(P<0.01),and the expression levels of DDIT4 mRNA and protein were increased(P<0.05 or P<0.01).After 48 of transfection,compared with LNCap group and mimic NC group,the expression level of miR-30c-5p in the LNCap cells in miR-30c-5p mimic group was increased(P<0.01).Compared with LNCap group and sh-NC group,the expression level of DDIT4 mRNA in the LNCap cells in sh-DDIT4 group was decreased(P<0.01).Compared with miR-30c-5p mimic group and miR-30c-5p mimic+pcDNA3.1 NC group,the expression level of miR-30c-5p in The LNCap cells in miR-30c-5p mimic+pc-DNA3.1-DDIT4 group was decreased(P<0.01);compared with miR-30c-5p mimic group and miR-30c-5p mimic+pcDNA3.1 NC group,the expression level of DDIT4 mRNA in the LNCap cells in miR-30c-5p mimic+pc-DNA3.1-DDIT4 group was increased(P<0.01);compared with miR-30c-5p mimic group and miR-30c-5p mimic+pcDNA3.1 NC group,the expression level of DDIT4 protein in the LNCap cells in miR-30c-5p mimic+pc-DNA3.1-DDIT4 group was increased(P<0.05).The CCK-8 method results showed that compared with LNCap group and mimic NC group,the proliferation rate of the LNCap cells in miR-30c-5p mimic group was decreased(P<0.01);compared with LNCap group and sh-NC group,the proliferation rate of the LNCap cells in sh-DDIT4 group was decreased(P<0.01);compared with miR-30c-5p mimic group and miR-30c-5p mimic+pcDNA3.1 NC group,the proliferation rate of the LNCap cells in miR-30c-5p mimic+pc-DNA3.1-DDIT4 group was increased(P<0.01).The Transwell assay results showed that compared with LNCap group and mimic NC group,the number of the invasion LNCap cells in miR-30c-5p mimic group was decreased(P<0.01);compared with LNCap group and sh-NC group,the number of invasion LNCap cells in sh-DDIT4 group was decreased(P<0.01);compared with miR-30c-5p mimic group and miR-30c-5p mimic+pcDNA3.1 NC group,the number of the invasion LNCap cells in miR-30c-5p mimic+pc-DNA3.1-DDIT4 group was increased(P<0.01).The scratch assay results showed that compared with LNCap group and mimic NC group,the scratch healing rate of the LNCap cells in miR-30c-5p mimic group was decreased(P<0.01);compared with LNCap group and sh-NC group,the scratch healing rate of the LNCap cells in sh-DDIT4 group was decreased(P<0.01);compared with miR-30c-5p mimic group and miR-30c-5p mimic+pcDNA3.1 NC group,the scratch healing rate of the LNCap cells in miR-30c-5p mimic+pc-DNA3.1-DDIT4 group was increased(P<0.01).The dual-luciferase reporter assay results showed that compared with the LNCap cells co-transfected with WT-DDIT4 and mimic NC,the luciferase activity of the LNCap cells co-transfected with WT-DDIT4 and miR-30c-5p mimic was decreased(P<0.01).The in vivo nude mouse tumor formation experiment results showed that on the 3 rd,6 th,9 th,12 th,and 15th days after cell injection,compared with blank group and agomiR-NC group,the tumor volumes of the nude mice in agomiR-30c-5p group were decreased(P<0.05).The HE staining results showed that in prostate cancer tissue of the mice in blank group and agomiR-NC group,the cell nuclei were enlarged,and nucleoli were prominent and deformed.In the mice in agomiR-30c-5p group,some regions of prostate cancer tissues results showed neatly arranged cells with normally shaped nuclei.The RT-qPCR and immunofluorescence staining showed that compared with agomiR-NC group,the expression level of miR-30c-5p in prostate cancer tissue of the mice in agomiR-30c-5p group was increased(P<0.01).Compared with blank group and agomiR-NC group,the expression level of DDIT4 mRNA in prostate cancer tissue of the mice in agomiR-30c-5p group was decreased(P<0.01).DDIT4 protein was mainly expressed in the cytoplasm.Compared with blank group and agomiR-NC group,the fluorescence intensity of DDIT4 protein in prostate cancer tissue of the mice in agomiR-30c-5p group was decreased(P<0.01).Conclusion:The expression level of miR-30c-5p in the prostate cancer LNCap cells is decreased,and it inhibits the proliferation,migration,and invasion of the prostate cancer cells by targeting downregulation of DDIT4,thereby participating in the occurrence and development of prostate cancer.

Objective To screen and verify the genes that play key role in the occurrence and development of esophageal cancer by u-sing bioinformatics and real-time fluorescence quantitative PCR(qRT-PCR)methods to find new markers for diagnosis of esophageal cancer(ESCA).Methods Using the TCGA database and Wayne plot analysis,the cross genes between the differentially expressed genes of ESCA and the genes which have the most significant impacts on disease-free survival(DFS)rate in esophageal cancer patients were preliminarily identified.Following conducting protein-protein interaction(PPI)network analysis on the overlapping genes,GO and KEGG functional analysis was performed to screen the potential key genes as the diagnostic markers of esophageal cancer.qRT-PCR was used to quantitatively analyze the expression of mRNA of the key gene in peripheral blood.Statistical analysis was con-ducted based on the clinico-pathological characteristics of the patients to determine its potential value as a new diagnostic marker for e-sophageal cancer.Results After overlapping of differentially expressed genes of ESCA and disease-free survival genes in the TCGA database,39 upregulated genes and 20 downregulated genes were found to be differentially expressed,all of which affected disease-free survival rate.After conducting PPI network analysis,15 upregulated genes with core interactions were identified,and the downregulat-ed genes did not form any interaction network.Further enrichment analysis of these 15 core interacting genes through GO and KEGG,revealed that fibronectin 1(FN1)may be a potential biomarker for ESCA diagnosis.The qRT-PCR results showed that compared with the healthy control group,the mRNA expression level of FN1 in the peripheral blood of esophageal cancer patients was significantly ele-vated.After analyzing the clinical characteristics of patients,it was found that the patients with poor differentiation and high clinico-pathological staging had significantly increased peripheral blood FN1 mRNA levels.The model with FN1 mRNA expression levels can distinguish esophageal cancer patients from healthy individuals.Conclusion FN1 mRNA may be a potential non-invasive diagnostic biomarker for esophageal cancer.

Objective:To quantify the associations between periconceptional maternal homocysteine (HCY) and offspring′s birth weight and risk of small for gestational age (SGA) infant.Methods:The 19 984 mother-child pairs in this prospective cohort study were recruited from the Shanghai preconception cohort; the infants were delivered from 1 st September 2016 to 11 th November 2022. A standardized questionnaire was used to collect the mothers′ demographic information, medical history, dietary supplement use, and maternal complications during pregnancy, and their serum samples were collected. Serum HCY, folate, and vitamin B 12 were measured using chemiluminescent microparticle immunoassay based on serum sample drawn at enrollment. Birth weight data were obtained from medical records. Multiple imputation methods were applied to handle missing data in key variables. Multivariable linear regression and Poisson regression models were used to analyze the relationship between maternal HCY concentration during the periconceptional period and the birth weight and SGA risk of the offspring. Results:A total of 9 452 pairs were enrolled preconceptionally and the remaining 10 532 pairs were enrolled in early pregnancy. The proportion of mothers whose pregnancy age was greater than 35 years was 9.2% (1 832/19 984), the proportion of primiparous women was 76.5% (15 283/19 984), the proportion of pre-pregnancy overweight and obesity was 14.0% (2 804/19 984), the proportion of using folic acid supplements before pregnancy was 21.4% (4 272/19 984), and the proportion of those who supplemented with folic acid during early pregnancy was 85.2% (8 976/10 532); gestational diabetes mellitus was in 6.2% (1 245/19 984), gestational hypertensive syndrome in 3.6% (711/19 984). The birth weight of the offspring was (3 297±468) g, and there were 1 962 SGA children (9.8%). The HCY concentration in the overall population in appropriate for gestational age during the periconceptional period was (7.9±3.2) μmol/L, with (8.3±3.7) μmol/L in the preconception subgroup and (7.3±2.4) μmol/L in the early pregnancy subgroup. After adjustment for the covariates of perinatal demographic information, adverse pregnancy outcomes, serum folate and vitamin B 12, increased maternal periconceptional HCY was significantly associated with lower offspring birth weight ( β=-2.30, 95% CI -4.43--0.16, P=0.035). Only the early pregnancy subgroup was significantly associated with lower offspring birth weight ( β=-7.39, 95% CI-11.50--3.21, P<0.001). No association was found between peripregnancy HCY and offspring SGA risk. However, elevated HCY in early pregnancy was associated with an increased risk of SGA in the offspring ( RR=1.05, 95% CI 1.01-1.08, P=0.002). Periconceptional vitamin B 12 was a mediator of the association between HCY and offspring birth weight, accounting for 16.5%, 41.2% and 5.4% of its total effect in the overall periconceptional population, the pre-pregnancy subgroup and the early pregnancy subgroup, respectively. Conclusions:Maternal periconceptional HCY level is associated with lower birth weight in offspring, but not with the risk of SGA. Elevated maternal HCY in early pregnancy subgroup may be associated with increased risk of SGA in offspring.