Objective To explore the impact of number of positive regional lymph nodes (nPRLN) in N1 stage on the prognosis of non-small cell lung cancer (NSCLC) patients. Methods Patients with TxN1M0 stage NSCLC who underwent lobectomy and mediastinal lymph node dissection from 2010 to 2015 were screened from SEER database (17 Regs, 2022nov sub). The optimal cutoff value of nPRLN was determined using X-tile software, and patients were divided into 2 groups according to the cutoff value: a nPRLN≤optimal cutoff group and a nPRLN>optimal cutoff group. The influence of confounding factors was minimized by propensity score matching (PSM) at a ratio of 1 : 1. Kaplan-Meier curves and Cox proportional hazards models were used to evaluate overall survival (OS) and lung cancer-specific survival (LCSS) of patients. Results A total of 1316 patients with TxN1M0 stage NSCLC were included, including 662 males and 654 females, with a median age of 67 (60, 73) years. The optimal cutoff value of nPRLN was 3, with 1165 patients in the nPRLN≤3 group and 151 patients in the nPRLN>3 group. After PSM, there were 138 patients in each group. Regardless of before or after PSM, OS and LCSS of patients in the nPRLN≤3 group were superior to those in the nPRLN>3 group (P<0.001). N1 stage nPRLN>3 was an independent prognostic risk factor for OS [HR=1.52, 95%CI (1.22, 1.89), P<0.001] and LCSS [HR=1.72, 95%CI (1.36, 2.18), P<0.001]. Conclusion N1 stage nPRLN>3 is an independent prognostic risk factor for NSCLC patients in TxN1M0 stage, which may provide new evidence for future revision of TNM staging N1 stage subclassification.

Objective: To investigate the characteristics and potential risk factors associated with HIV infection among newly reported HIV positive male student cases in Jiangsu Province from 2023 to 2024, so as to provide evidence for targeted intervention strategies. Methods: Data were obtained from the China CDC Surveillance System on newly reported HIV positive male student cases from 2023 to 2024. A survey was conducted to collect information on demographic characteristics, knowledge of AIDS prevention, education and training history, HIV testing history, behavioral and substance use patterns, and other relevant factors prior to HIV diagnosis among 343 newly reported HIV positive male student cases in Jiangsu Province. Multivariate Logistic regression analysis was used to assess the risk factors of HIV infection among male students. Results: Among the HIV positive male student cases, homosexual behavior accounted for 93.88% of transmission routes, while 10.20% involved heterosexual contact, as well as 4.08% for two sexual hehaviors. Awareness of HIV prevention knowledge was 97.08%, and 66.76% had previously undergone HIV testing. Among the respondents, 10.50% had used rush poppers as enhancers, and 72.30% had received HIV prevention education within the past year. Among students cases with homosexual behavior, the median time from first homosexual contact to HIV diagnosis was ≤2 years, with 54.66% of cases falling into this category; the most common way of finding same sex partners was through social software, accounting for 88.20% of cases, while the proportion of those via "Blued" app reached 87.07% ; the proportion of using condoms every time during sexual activity in the past six months was 12.27%. Among the student cases with homosexual behavior, the results of multiple Logistic regression analysis showed that student cases aged 18 to 24 ( OR =4.52) and >24 ( OR = 19.23 ), without receiving education on HIV prevention in the past year ( OR =1.86), having consistent condom use ( OR =2.73) and not using condoms ( OR =2.12) during the last sexual activity were more likely to had the first same sex sexual activity for more than 3 years before being diagnosed as HIV positive cases (all P <0.05). Student cases who were uncertain about their partner s sexual identity ( OR =0.33), and who primarily identified same sex partners through "other" means ( OR = 0.23 ) were more likely to avoid HIV testing; in contrast, student cases with consistent condom use during the last homosexual encounter ( OR =7.20) was significantly associated with increased likelihood of HIV testing (all P <0.05). Conclusions Newly reported HIV positive male student cases in Jiangsu Province exhibit serious discrepancies between knowledge and practice regarding HIV prevention. Measures are needed to accelerate the optimization of campus based HIV prevention education content and delivery methods. Simultaneously, enhanced management of extracurricular male populations is essential to effectively control the spread of HIV.

OBJECTIVE: To analyze the phenotype and genotype of a neonate with Osteo-oto-hepato-enteric syndrome (O2HE) and review the literature. METHODS: A female neonate diagnosed with O2HE syndrome on December 13, 2024 at the First Affiliated Hospital of Zhengzhou University was selected as the study subject, and her clinical characteristics were analyzed, and pathogenic variants were explored by whole exome sequencing (WES). This study was approved by the Medical Ethics Committee of the Hospital (Ethics No.: 2025-KY-1038). RESULTS: The proband, a female infant, was delivered by Cesarean section at 36⁺¹ weeks of gestation. Five days after birth, she had developed severe diarrhea, mild cholestasis, sensorineural hearing loss, and growth retardation. WES revealed that she has harbored novel compound heterozygous variants c.512delA (p.Lys171Serfs*64) and c.698C>A (p.Thr233Asn) of the UNC45A gene, which were inherited from her mother and father, respectively. A total of 8 English papers were retrieved, which involved 16 patients from 14 families. Combined with our case, the 17 patients included 13 (76.5%) females and 4 (23.5%) males. Four patients (23.5%) had consanguineous parents. One case was excluded from further genetic analysis due to co-morbidity with other genetic variants. The primary clinical features included diarrhea (87.5%), cholestasis (81.3%), sensorineural hearing loss (31.3%), bone fragility (37.5%), and developmental delay (50.0%). Bi-allelic compound heterozygous mutations were identified in 12 patients (75.0%), and homozygous variants in 4 (25.0%). These included missense, nonsense, frameshift and deletional variants. The c.710T>C (p.Leu237Pro) variant was identified for 5 times, 3 of which were in homozygote forms. CONCLUSION O2HE syndrome should be suspected in cases with diarrhea, cholestasis, and hearing abnormalities during early postnatal period. Genetic testing facilitate early identification, genetic diagnosis and treatment.
Humans ; Female ; Infant, Newborn ; Male ; Mutation ; Hearing Loss, Sensorineural/genetics* ; Diarrhea, Infantile/genetics* ; Exome Sequencing ; Phenotype ; Fetal Growth Retardation ; Hair Diseases ; Facies

Background Pyrethroid pesticides (PYRs) can cross the placental barrier to cause intrauterine fetal exposure, which may lead to developmental immunotoxicity (DIT). However, the specific effect of maternal PYR exposure during pregnancy on the cellular immune function of 1-year-old children remains unclear. Objective To explore the effect of PYRs exposure throughout the entire pregnancy on peripheral blood lymphocytes in 1-year-old children and potential sensitive window period of PYRs exposure. Methods A birth cohort was established by enrolling pregnant women in their first trimester and following them and their infants until one year of age. Ultra-high performance liquid chromatography-tandem mass spectrometry was used to detect the levels of PYRs metabolites, including 3-phenoxybenzoic acid (3PBA), 4-fluoro-3-phenoxybenzoic acid (4F3PBA), and cis-3-(2,2-dichlorovinyl)-2,2- dimethylcyclopropane carboxylic acid (cis-DBCA), in the urine of pregnant women during the first trimester (gestational weeks 6-12), the second trimester (gestational weeks 21-24), and the third trimester (gestational weeks 33-36). Peripheral blood leukocyte and lymphocyte counts were measured in children at 12 months of age using the Coulter principle combined with flow cytometry. Exposure levels of PYRs metabolites in each trimester were divided into low, moderate, and high exposure groups based on the 25th (P₂₅) and 75th (P₇₅) percentiles. Meanwhile, participants were classified as having repeated high or low exposure if their metabolite levels were > P₇₅ or <P₂₅ in at least two trimesters, respectively, while all others were categorized as having repeated moderate exposure. Generalized linear models were used to analyze the associations between trimester-specific and repeated PYRs metabolite exposure levels and the peripheral blood white blood cell (WBC) and lymphocyte counts in children aged 1 year. Results A total of 336 mother-child pairs were included in this study. For the pregnant women, the total detection rates of maternal urinary 3PBA, 4F3PBA, and cis-DBCA across the three trimesters of pregnancy were 80.5%, 100.0%, and 81.3%, respectively; and median creatinine-corrected concentrations were 0.24, 0.36, and 0.42 μg·g⁻¹, respectively. In children aged 1 year, the mean WBC and lymphocyte counts in peripheral blood were (8.9±2.0)×10⁹·L⁻¹ and (5.7±1.6)×10⁹·L⁻¹, respectively. The results of the generalized linear model analysis indicated that compared to the low exposure group, the high cis-DBCA exposure group during the third trimester of pregnancy had significantly lower peripheral blood WBC count (β=−0.87, 95%CI: −1.51, −0.23) and lymphocyte count (β=−0.64, 95%CI: −1.15, −0.13); and the repeated high-exposure group of cis-DBCA had significantly lower peripheral blood WBC count (β=−1.34, 95%CI: −2.34, −0.34) and lymphocyte count (β=−0.80, 95%CI: −1.60, −0.01) than the repeated low exposure group. Similarly, the repeated moderate-exposure group of cis-DBCA had a significantly lower peripheral blood WBC count (β=−0.83, 95%CI: −1.59, −0.07) than the repeated low exposure group. Conclusion High maternal exposure to PYRs with cis-DBCA as the major metabolite exposure is associated with decreased peripheral leukocyte and lymphocyte counts in children aged 1 year, and repeated high-level exposure throughout gestation appears to exacerbate DIT in offspring. The third trimester of pregnancy maybe a sensitive window for children's DIT induced by exposure to PYRs during pregnancy.

Objective: To explore the importance of selecting appropriate human antiserum for absorption and elution tests by analyzing two cases in which weak A antigens were detected using this method. Methods: The microcolumn agglutination and tube methods were used to perform ABO blood group typing of the patients. Absorption and elution tests were conducted to detect weak A antigens on red blood cells. Molecular biological methods were employed for genotyping. Results: Serological tests showed that the forward typing results of the two patients were O and B, respectively, and weak anti-A1 antibodies were present in their sera. When O-type human high-titer (anti-A≥256) serum was used for absorption and elution tests, patient 1 eluted anti-A, confirming the presence of weak A antigens on their red blood cells; patient 2 eluted anti-A and anti-AB simultaneously. When B-type human antiserum was used for absorption and elution, patient 2 eluted anti-A, confirming the presence of weak A antigens on their red blood cells as well. Gene sequencing results showed that the genotypes of the two patients were ABO Aw. 04/ABO O. 01. 02 and ABO AEL (c. 410C>T)/ABO B.01, respectively. Conclusion: When absorption and elution tests are needed for weak A/B antigens alone on red blood cells, O-type human high-titer serum can be prioritized. However, when both A and B antigens are present, the human antiserum selected for absorption and elution tests should only react with the weak antigen and not with the normally expressed antigen.

Objective To investigate the potential mechanism by which dihydromyricetin(DHM)ameliorates diabetic nephropathy(DN),and to screen and validate its possible key molecular targets.Methods A DN model was established using db/db mice,and 100 mg/(kg·d)DHM was administered via gavage 5 d per week for totally 10 weeks.Renal morphological changes were observed after staining to evaluate the effects of DHM.GSE161885 and GSE270526 datasets were obtained from the Gene Expression Omnibus(GEO)database and analyzed in combination with the GeneCards database to screen for DN-related differentially expressed genes(DEGs).Protein-protein interaction(PPI)network and molecular docking were employed to predict potential DHM targets.Western blotting and immunofluorescence staining were performed to detect the effects of DHM on pyroptosis-related pathways in the renal tissues of db/db mice and in high glucose(HG)-induced human renal tubular epithelial cells(HK-2).The specific NLR family pyrin domain containing protein 3(NLRP3)inhibitor MCC950 was also used to validate the predicted mechanism.Results In vivo experiments showed that DHM significantly ameliorated renal pathological damage in db/db mice,alleviated glomerular hypertrophy and mesangial expansion,and markedly reduced Paller scores(P<0.001).Immunofluorescence staining revealed significantly weakened fluorescence signals for α-smooth muscle actin(α-SMA),fibronectin,and collagen Ⅰ in renal tissues.Western blot results showed that the expression levels of collagen Ⅰ,collagen Ⅲ,α-SMA,and transforming growth factor beta 1(TGF-β1)were significantly decreased(P<0.05).A total of 16 DN-related DEGs were identified.Enrichment analysis revealed that these genes were primarily enriched in pathways such as viral protein interactions,cytokine-cytokine receptor interaction,and the AGE-RAGE signaling pathway in diabetic complications,and were primarily involved in gene functions such as the positive regulation of lymphocyte-mediated immunity,positive regulation of adaptive immune response,and chemokine activity.Molecular docking confirmed NLRP3 as a potential target of DHM.In vivo validation showed that DHM significantly down-regulated gasdermin-D(GSDMD)fluorescence signals and inhibited the expression of pyroptosis-related proteins including NLRP3,Caspase 1,Cleaved-Caspase 1,interleukin 18(IL-18),and GSDMD(P<0.05).In vitro studies further confirmed that both DHM and the specific NLRP3 inhibitor MCC950 alleviate high glucose-induced fibrosis and pyroptosis in HIC-2 cells.Conclusion DHM can ameliorate the progression of DN,and its mechanism is related to inhibiting NLRP3 inflammasome-mediated pyroptosis,thereby alleviating renal inflammation and fibrosis.

OBJECTIVE To evaluate cerebrospinal fluid(CSF)flow dynamics and volume changes of pulsatile tinnitus(PT)patients caused by sigmoid sinus wall dehiscence(SSWD)with different intracranial pressure via MRI.METHODS Prospective enrolled 35 SSWD-PT patients with intracranial hypertension,25 SSWD-PT patients with normal intracranial pressure and 35 age-,sex-matched healthy controls.Demographic characteristics were recorded.Intracranial pressure was assessed by the index of transverse sinus stenosis(ITSS)and morphology changes.CSF flow dynamics were evaluated via phase-contrast magnetic resonance imaging(PC-MRI)and CSF volume were evaluated via three-dimensional T1-weighted turbo field echo(3D T1-TFE)sequence and ITK-SNAP software.Compared the differences of each index between three groups.RESULTS The mean flux and regurgitant fraction were significantly different among the three groups(P<0.05).The intracranial hypertension group presented significantly decreased mean flux(MF)and significantly increased regurgitant fraction(RF)compared to controls(P<0.017).There were no significant differences in MF and RF of normal intracranial pressure group compared with intracranial hypertension group and control group(P>0.017).There were no statistical differences in age,sex,body mass index,forward flow volume,backward flow volume,mean velocity,peak velocity,stroke volume and CSF volume(P>0.05).CONCLUSION SSW D-PT patients have abnormal changes in CSF,and those with increased intracranial pressure are more obvious.These changes may be associated with abnormal hemodynamics in the sigmoid sinus and the occurrence of PT.

Objective To explore the expression levels and clinical significance of serum eosinophil derived neurotoxin(EDN)and prostaglandin D2(PGD2)in children with respiratory syncytial viruses(RSV)pneu-monia with wheezing.Methods A total of 96 children with RSV pneumonia admitted to the hospital from March 2021 to September 2023 were selected case group,who were divided into wheezing group(n=51)and non-wheezing group(n=45)according to whether they were combined with wheezing or not.The children a-mong wheezing group were divided into mild group(n=23),moderate group(n=17)and severe group(n=11)according to the degree of disease.And the children among wheezing group were also divided into effective group(n=41)and non-effective group(n=10)according to therapeutic effect after treatment for one week.In the same period,60 children were randomly selected as control group.Serum EDN and PGD2 levels were measured by enzyme-linked immunosorbent assay.Spearman's rank correlation was used to analyse the associ-ation between serum EDN,PGD2 and degree of disease.Logistic regression was used to analyse the association between serum EDN,PGD2 and clinical efficacy of children with wheezing and receiver operating characteristic(ROC)curve was used to evaluate the predictive value of serum EDN,PGD2 on the clinical effective of chil-dren with wheezing.Results Serum EDN and PGD2 levels were higher in case group than those in control group(P＜0.05).Serum EDN and PGD2 levels were higher in wheezing group than those in non-wheezing group(P＜0.05).Serum EDN and PGD2 levels were increased sequentially in mild group,moderate group and severe group(P＜0.05).Serum EDN and PGD2 levels were positively associated with degree of disease in children with wheezing(P＜0.05).Elevated EDN and PGD2 were risk factors for ineffective clinical efficacy in children with wheezing(OR=1.241,1.225,1.309,P＜0.05).The area under the curve of serum EDN and PGD2 and combined detection to predict the clinical efficacy was 0.778,0.785,0.879,respectively,and the predictive value of combined indicators was greater than that of single indicator(Z=1.956,1.871,P=0.029,0.033).Conclusion Up-regulation of serum EDN and PGD2 expression is involved in wheezing process of children with RSV pneumonia,which is closely related to degree of disease and clinical efficacy.Early com-bined examination of two indicators may assist in the clinical assessment of degree of disease and prediction of clinical efficacy in children with wheezing.

Objective:To evaluate the value of a combined model based on primary lesion 18F-fluorodeoxyglucose ( 18F-FDG) PET/CT radiomics for predicting lymph node metastasis in non-small cell lung cancer (NSCLC) . Methods:A retrospective analysis was conducted on the clinical data of 203 NSCLC patients who underwent pre-treatment PET/CT imaging at Nanjing Drum Tower Hospital from June 2013 to July 2023. Patients were randomly assigned to the training set ( n=142) and the validation set ( n=61) at a ratio of 7∶3. A predictive model was developed in the training set, and its predictive performance and clinical application value were assessed in both the training and validation sets. Traditional PET/CT parameters and PET/CT radiomics features of the primary lesion were obtained by 3D-slicer software. Least absolute shrinkage and selection operator (LASSO), random forest, and extreme gradient boosting were performed to extract features. Support vector machine was used to construct a radiomics score (Radscore). Univariate and multivariate logistic regression analysis was used to predict the influencing factors of lymph node metastasis in NSCLC patients and to establish models. Predictive performance of the models was evaluated by receiver operator characteristic (ROC) curves and clinical application value was assessed by calibration curves and decision curve analysis (DCA) . Results:Among 203 NSCLC patients, 116 had lymph node metastasis, with 64 cases in the training set and 52 cases in the validation set. Three complementary classical machine learning methods were used for feature screening, and finally 10 radiomics features were obtained. The optimal threshold for Radscore-PET was 0.43 and the optimal threshold for Radscore-CT was 0.39. Univariate analysis showed that, sex ( OR=0.48, 95% CI: 0.24-0.95, P=0.036), tumor marker levels ( OR=3.81, 95% CI: 1.84-7.91, P<0.001), long diameter of tumor ( OR=2.56, 95% CI: 1.27-5.16, P=0.009), short diameter of tumor ( OR=3.73, 95% CI: 1.75-7.92, P=0.001), vacuolar sign ( OR=0.32, 95% CI: 0.12-0.86, P=0.024), ring-like metabolism ( OR=3.67, 95% CI: 1.33-10.13, P=0.012), maximum standardized uptake value (SUV max) ( OR=6.57, 95% CI: 3.03-14.25, P<0.001), metabolic tumor volume (MTV) ( OR=2.91, 95% CI: 1.43-5.92, P=0.003), total lesion glycolysis (TLG) ( OR=4.23, 95% CI: 2.08-8.59, P<0.001), Radscore-PET ( OR=21.93, 95% CI: 9.04-53.20, P<0.001) and Radscore-CT ( OR=13.72, 95% CI: 6.12-30.76, P<0.001) were all influencing factors for predicting lymph node metastasis in NSCLC patients. Multivariate analysis showed that, tumor marker levels ( OR=2.55, 95% CI: 1.11-5.90, P=0.028), vacuolar sign ( OR=0.26, 95% CI: 0.08-0.83, P=0.023), SUV max ( OR=5.94, 95% CI: 1.99-17.75, P=0.001), Radscore-PET ( OR=25.51, 95% CI: 5.92-110.22, P<0.001), and Radscore-CT ( OR=8.68, 95% CI: 2.73-27.61, P<0.001) were independent influencing factors for predicting lymph node metastasis in patients with NSCLC. Based on the above independent influencing factors, models were constructed: the traditional model (tumor marker levels, vacuolar sign, SUV max), the PET model (SUV max, Radscore-PET), the CT model (vacuolar sign, Radscore-CT), and the combined model (tumor marker levels, vacuolar sign, SUV max, Radscore-PET, Radscore-CT). ROC curve analysis showed that, the area under curve (AUC) of the traditional, PET, CT, and combined models in the training set were 0.75 (95% CI: 0.67-0.82), 0.90 (95% CI: 0.84-0.95), 0.85 (95% CI: 0.78-0.90), and 0.94 (95% CI: 0.88-0.97), respectively. The predictive value of the combined model was higher than that of the traditional model ( Z=5.01, P<0.001), the PET model ( Z=1.99, P=0.047), and the CT model ( Z=3.25, P=0.001). In the validation set, the AUCs for the traditional model, PET model, CT model, and combined model were 0.65 (95% CI: 0.52-0.77), 0.86 (95% CI: 0.74-0.93), 0.85 (95% CI: 0.73-0.93), and 0.90 (95% CI: 0.80-0.96), respectively. The predictive value of the combined model was superior to that of the traditional model ( Z=3.23, P=0.001). The sensitivity and specificity of the combined model in the training set were 84.37% and 91.03%, while in the validation set, the sensitivity and specificity were 82.61% and 94.74%, respectively. Calibration curves showed a good agreement between the predicted and actual probabilities in both the training and validation sets. DCA showed that the combined models had good discriminative ability in both the training and validation sets. Conclusions:Tumor marker levels, vacuolar sign, SUV max, Radscore-PET, and Radscore-CT are all independent influencing factors for predicting lymph node metastasis in patients with NSCLC. The combined model based on these factors demonstrates excellent predictive performance and clinical application value for predicting lymph node metastasis in NSCLC.

Objective:To analyze the disease burden of colorectal cancer (CRC) among young and middle-aged people in China from 1990 to 2021, and to explore the influence of age, period and cohort on the incidence and mortality of CRC in young and middle-aged people of China.Methods:Data on CRC in patients aged 40-59 years in China from 1990 to 2021 were extracted from the Global Burden of Disease Study 2021 (GBD 2021) database. Statistics such as incidence rate, mortality rate, disability-adjusted life years (DALY), and their corresponding age-standardized rates were calculated to analyze the CRC incidence and mortality in different age and sex groups of young and middle-aged Chinese young people from 1990 to 2021. The Joinpoint regression model was used to analyze the CRC incidence, the mortality and the DALY rate, as well as to calculate the annual percentage change (APC) and the average annual percentage change (AAPC). The effects of three independent factors, namely age, period and cohort, on the incidence and mortality of CRC in young and middle-aged people of China were analyzed and evaluated through the age-period-cohort model.Results:From 1990 to 2021, there was a remarkable upward trend in the incidence, mortality, and DALY of CRC among Chinese young and middle-aged adults. In 2021, the number of incidence cases of CRC among young and middle-aged people in China reached 181 000, and the number of deaths reached 57 900, which were 236.80% and 75.48% higher than those in 1990 (53 800 and 33 000, respectively). During the same period, DALY increased by 62.59%, with the 55-59 age group having the largest increase at 83.35%. From 1990 to 2021, the age-standardized incidence rate (ASIR) increased by 49.04%, rising from 25.51/100 000 to 38.02/100 000, and the age-standardized mortality rate (ASMR) declined by 28.75%, decreasing from 17.01/100 000 to 12.12/100 000, respectively. The increase in ASIR was the greatest among the 40-44 age group, reaching 57.31%, while the decline in ASMR was the most significant among the 50-54 age group, amounting to 30.18%. However, the DALY rate declined by 26.66%, from 673.52/100 000 to 493.94/100 000. The decline in DALY was the greatest among the 50-54 age group, reaching 28.26%. Joinpoint regression model analysis showed that, from 1990 to 2021, the incidence of CRC in Chinese young and middle-aged adults rose on average by 1.32% annually, and the increase was higher in men (1.87%) than that in women (0.36%). The mortality rate showed a downward trend, with an average annual decline of 1.10%, with a higher decline in women than in men (-2.14% vs. -0.50%). The DALY rate showed a downward trend, with an average annual decline of 1.00%, and more decline in women than in men (-2.06% vs. -0.41%). All of these trends were statistically significant (all P<0.001). The age-period-cohort model analysis showed that, the net drift of CRC incidence was 1.21% (1.02%-1.41%) per year among Chinese young and middle-aged adults between 1990 and 2021, while the net drift in mortality was -1.40% (-1.59%--1.21%) per year. The impact of age on CRC incidence and mortality intensified with advancing age. Incidence attributable to age rose from 12.66% (11.90%- 13.46%) in the 40-44 age group to 56.68% (54.37%-59.08%) in the 55-59 age group. Similarly, mortality attributable to age increased from 6.47% (6.12%-6.85%) in the 40-44 age group to 25.74% (24.58%-26.96%) in the 55-59 age group. In all age groups, the role of CRC incidence and mortality attributable to age was higher in men than in women. Period effects on the RR value of CRC incidence showed a declining trend followed by an upward trend, with the highest risk during 2015-2019 ( RR=1.36, 95% CI: 1.28-1.43), using 2000-2004 as the reference. For mortality, period effects exhibited a declining trend, with the highest risk during 1990-1994 ( RR=1.23, 95% CI: 1.15-1.32), using 2000-2004 as the reference. Cohort effects indicated that later birth cohorts had higher incidence risks, with the highest incidence observed in the 1973-1977 birth cohort ( RR=1.30, 95% CI: 1.16-1.45), using the 1953-1957 birth cohort as the reference. Conversely, later birth cohorts had lower mortality risks, with the lowest mortality in the 1973-1977 birth cohort ( RR=0.78, 95% CI: 0.69-0.88), using the 1953-1957 birth cohort as the reference. Conclusions:From 1990 to 2021, the changes in the disease burden of CRC among young and middle-aged people in China are manifested as an increase in standardized incidence rate and a decrease in standardized mortality rate. Meanwhile, there are gender differences in the trend of temporal changes. Age, period and cohort all have a significant impact on the incidence and mortality trends of colorectal cancer in young and middle-aged people. Research on the etiology of CRC should be strengthened, and targeted prevention and control strategies should be formulated.