[Objective] To establish a cryopreservation protocol for small-volume (≤1 mL) red blood cells (RBCs) and to evaluate the reactivity and stability of blood group antigens after cryopreservation, so as to explore its potential application in immunohematology reference laboratories. [Methods] Small-volume RBCs were cryopreserved for 120 days, followed by thawing and deglycerolization to restore the RBC components. The quality of the RBCs was assessed. Serum antibodies were serially diluted and reacted with RBCs before and after cryopreservation, and agglutination scores were recorded to quantitatively evaluate the reactivity and stability of blood group antigens such as Rh, Duffy, Lewis, Kidd, M, and H. Flow cytometry was used to analyze the percentage and mean fluorescence intensity of ABO antigen expression on RBCs before and after cryopreservation to assess the usability of cryopreserved RBCs in flow immunophenotyping and blood group subtype studies. [Results] The hemolysis rate of thawed and deglycerolized RBCs was (0.27±0.10)%, with a supernatant free hemoglobin level of (0.52±0.14) g/L, and the RBC recovery rate was (69.12±7.91)%. The direct antiglobulin test (DAT) was negative for all thawed RBCs. There was no difference in the reactivity of blood group antigens before and after cryopreservation, and no difference in the percentage and mean fluorescence intensity of A and B antigen expression on RBCs before and after cryopreservation. [Conclusion] The small-volume RBC cryopreservation protocol can be applied to immunohematology analysis in reference laboratories and is expected to be widely used in blood group identification, antibody screening, identification, and blood group-related research.

Objective:To investigate the prevalence of and risk factors associated with Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT) and high-risk human papillomavirus (HPV) coinfections among patients with newly diagnosed syphilis at a hospital in Nanjing. Methods:A cross-sectional study was conducted on patients with newly diagnosed syphilis at the STD Clinic, Hospital of Dermatology, Chinese Academy of Medical Sciences in Nanjing, China from May 2023 to April 2024. Urethral, cervical or rectal swabs were collected according to the gender and types of sexual behavior of the patients. Screening tests for CT, NG and HPV infections were then performed by nucleic acid amplification testing. High-risk HPV testing was performed only in female patients. Univariate analysis was carried out to investigate risk factors associated with CT infection. The chi-square test, chi-square test with continuity correction, or Fisher's exact test was chosen based on the sample size and expected values.Results:A total of 111 newly diagnosed syphilis patients with test specimens were collected, including 71 males (64%) and 40 females (36%), and their ages ranged from 16 to 87 years; there were 82 patients with early syphilis and 29 with late latent syphilis; the number of sexual partners in the past 3 months ranged from 0 to 3. Among the 60 male patients with early syphilis, 1 (1.7%) was co-infected with NG, and 12 (20%) with CT; among the 16 men who have sex with men, 7 (43.8%) were co-infected with CT, while 5 (11.4%) of the 44 heterosexual patients were co-infected with CT, showing a significant difference in CT infection rates between the two groups ( χ2 = 5.80, P = 0.016). Among the 22 female patients with early syphilis, 1 (4.5%) was co-infected with NG, and 8 (36.4%) with CT; among the 12 female patients aged < 25 years, 8 (66.7%) were infected with CT, while none of the 7 patients aged 25-44 years or the 3 patients aged ≥ 45 years were infected with CT, showing a significant difference in CT infection rates among the 3 age groups ( P = 0.005) ; among the 16 female patients with 1 sexual partner in the past 3 months, 3 were infected with CT, while 5 were infected with CT in the 6 female patients with 2-3 sexual partners in the past 3 months, with a significant difference in CT infection rates between the two groups ( P = 0.011). Out of the 40 female patients with syphilis, 16 (40%) were co-infected with high-risk HPV; the HPV infection rates did not differ among different age groups (age groups of < 25 years, 25-44 years, ≥ 45 years: 8/14, 2/9, 6/17, respectively; P = 0.265) . Conclusion:The CT infection rate was relatively high in patients with newly diagnosed early syphilis, and a relatively high infection rate of high-risk HPV was observed in female patients with syphilis aged < 25 years.

Objective:To investigate the correlation between uterine volume and intrauterine adhesion (IUA).Methods:From June 2018 to November 2019, totally 7 007 patients who underwent hysteroscopy in outpatient operating rooms of Gynecological Minimally Invasive Center, Beijing Obstetrics and Gynecology Hospital were retrospectively analyzed . Patients of reproductive age with IUA without uterine fibroids and adenomyosis were selected as IUA group, and patients of reproductive age without uterine fibroids and adenomyosis without IUA during the same period were selected as the control group. The propensity score matching (PSM) method was used to perform 1∶1 matching for the two groups of patients, matching variables included age, height, weight, body mass index (BMI), gravidity, parity, and number of abortion curettage. Whether there was any difference in uterine volume between the two groups of patients was compared, and whether uterine volume was an influencing factor of IUA was explored. The patients in IUA group were also categorized into mild, moderate and severe to explore whether uterine volume influenced the severity of IUA. Results:(1) After inclusion and exclusion criteria, 351 patients were included in IUA group and 2 986 patients in the control group. With PSM, 327 patients in IUA group and 327 patients in the control group were finally enrolled in this study. There were no statistically significant differences in age, height, weight, BMI, gravidity, parity, and number of abortion curettage between the two groups of patients after matching (all P>0.05). (2) After PSM, there was a significant difference between the uterine volume of IUA group (median: 44.23 cm 3) and the uterine volume of the control group (median: 57.20 cm 3; P<0.001). (3) Reduced uterine volume ( OR=0.961, 95% CI: 0.952-0.970) was an independent risk factor for IUA ( P<0.001). (4) Uterine volume had a significant effect on the severity of IUA ( P<0.001), the larger the uterine volume ( B=-0.030, 95% CI: -0.044 to -0.017), the less severe the IUA. Conclusions:Reduced uterine volume is an independent risk factor for IUA, and uterine volume has a significant effect on the severity of IUA. In patients with small uterine volume size, primary and secondary prevention of IUA should be emphasized.

Objective:To investigate the predictive value of uterine volume for intrauterine adhesion (IUA) caused by endometrial injury, and to provide a new perspective for the primary prevention of IUA.Methods:The clinical data of 7 007 patients of reproductive age who underwent outpatient hysteroscopy in the Gynecological Minimally Invasive Center, Beijing Obstetrics and Gynecology Hospital from June 2018 to November 2019 were retrospectively analyzed. Patients of reproductive age with IUA without uterine fibroids and adenomyosis were selected as the IUA group (351 cases), and patients of reproductive age without uterine fibroids and adenomyosis and without IUA during the same period were selected as the control group (2 986 cases). The uterine volume was compared between the two groups. Multivariate binary logistic regression analysis was used to determine whether uterine volume was an independent factor for the occurrence of IUA. Ordinal multinomial logistic regression was used to analyze the correlation between uterine volume and menstrual volume in IUA patients. Receiver operating characteristic (ROC) curve was used to analyze the predictive value of uterine volume for IUA caused by endometrial injury.Results:(1) The uterine volume of the IUA group was significantly smaller than that of the control group (median: 44.15 vs 62.59 cm 3; Z=-15.742, P<0.001). (2) Multivariate binary logistic regression analysis showed that decreased uterine volume was an independent risk factor for IUA ( OR=0.184, 95% CI: 0.139-0.245; P<0.001). (3) The area under the ROC curve of uterine volume to predict IUA was 0.756, and the optimal cut-off value of uterine volume to predict IUA was 51.49 cm 3. (4) The risk of IUA caused by endometrial injury in patients with uterine volume≤51.49 cm 3 was 4.658 times higher than that in patients with uterine volume>51.49 cm 3 (95% CI: 3.681-5.893; P<0.001). (5) The smaller the uterine volume ( β=-0.032, 95% CI:-0.046 to -0.018; P<0.001), the more likely the IUA patients were to have menorrhagia and amenorrhea. Conclusions:Uterine volume has a certain predictive value for the occurrence of IUA caused by endometrial injury. For patients with small uterine volume, it is necessary to be alert to the occurrence of IUA caused by endometrial injury and improve the awareness of primary prevention.

Objective:To investigate the prevalence of and risk factors associated with Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT) and high-risk human papillomavirus (HPV) coinfections among patients with newly diagnosed syphilis at a hospital in Nanjing. Methods:A cross-sectional study was conducted on patients with newly diagnosed syphilis at the STD Clinic, Hospital of Dermatology, Chinese Academy of Medical Sciences in Nanjing, China from May 2023 to April 2024. Urethral, cervical or rectal swabs were collected according to the gender and types of sexual behavior of the patients. Screening tests for CT, NG and HPV infections were then performed by nucleic acid amplification testing. High-risk HPV testing was performed only in female patients. Univariate analysis was carried out to investigate risk factors associated with CT infection. The chi-square test, chi-square test with continuity correction, or Fisher's exact test was chosen based on the sample size and expected values.Results:A total of 111 newly diagnosed syphilis patients with test specimens were collected, including 71 males (64%) and 40 females (36%), and their ages ranged from 16 to 87 years; there were 82 patients with early syphilis and 29 with late latent syphilis; the number of sexual partners in the past 3 months ranged from 0 to 3. Among the 60 male patients with early syphilis, 1 (1.7%) was co-infected with NG, and 12 (20%) with CT; among the 16 men who have sex with men, 7 (43.8%) were co-infected with CT, while 5 (11.4%) of the 44 heterosexual patients were co-infected with CT, showing a significant difference in CT infection rates between the two groups ( χ2 = 5.80, P = 0.016). Among the 22 female patients with early syphilis, 1 (4.5%) was co-infected with NG, and 8 (36.4%) with CT; among the 12 female patients aged < 25 years, 8 (66.7%) were infected with CT, while none of the 7 patients aged 25-44 years or the 3 patients aged ≥ 45 years were infected with CT, showing a significant difference in CT infection rates among the 3 age groups ( P = 0.005) ; among the 16 female patients with 1 sexual partner in the past 3 months, 3 were infected with CT, while 5 were infected with CT in the 6 female patients with 2-3 sexual partners in the past 3 months, with a significant difference in CT infection rates between the two groups ( P = 0.011). Out of the 40 female patients with syphilis, 16 (40%) were co-infected with high-risk HPV; the HPV infection rates did not differ among different age groups (age groups of < 25 years, 25-44 years, ≥ 45 years: 8/14, 2/9, 6/17, respectively; P = 0.265) . Conclusion:The CT infection rate was relatively high in patients with newly diagnosed early syphilis, and a relatively high infection rate of high-risk HPV was observed in female patients with syphilis aged < 25 years.

Objective:To investigate the correlation between uterine volume and intrauterine adhesion (IUA).Methods:From June 2018 to November 2019, totally 7 007 patients who underwent hysteroscopy in outpatient operating rooms of Gynecological Minimally Invasive Center, Beijing Obstetrics and Gynecology Hospital were retrospectively analyzed . Patients of reproductive age with IUA without uterine fibroids and adenomyosis were selected as IUA group, and patients of reproductive age without uterine fibroids and adenomyosis without IUA during the same period were selected as the control group. The propensity score matching (PSM) method was used to perform 1∶1 matching for the two groups of patients, matching variables included age, height, weight, body mass index (BMI), gravidity, parity, and number of abortion curettage. Whether there was any difference in uterine volume between the two groups of patients was compared, and whether uterine volume was an influencing factor of IUA was explored. The patients in IUA group were also categorized into mild, moderate and severe to explore whether uterine volume influenced the severity of IUA. Results:(1) After inclusion and exclusion criteria, 351 patients were included in IUA group and 2 986 patients in the control group. With PSM, 327 patients in IUA group and 327 patients in the control group were finally enrolled in this study. There were no statistically significant differences in age, height, weight, BMI, gravidity, parity, and number of abortion curettage between the two groups of patients after matching (all P>0.05). (2) After PSM, there was a significant difference between the uterine volume of IUA group (median: 44.23 cm 3) and the uterine volume of the control group (median: 57.20 cm 3; P<0.001). (3) Reduced uterine volume ( OR=0.961, 95% CI: 0.952-0.970) was an independent risk factor for IUA ( P<0.001). (4) Uterine volume had a significant effect on the severity of IUA ( P<0.001), the larger the uterine volume ( B=-0.030, 95% CI: -0.044 to -0.017), the less severe the IUA. Conclusions:Reduced uterine volume is an independent risk factor for IUA, and uterine volume has a significant effect on the severity of IUA. In patients with small uterine volume size, primary and secondary prevention of IUA should be emphasized.

Objective:To investigate the predictive value of uterine volume for intrauterine adhesion (IUA) caused by endometrial injury, and to provide a new perspective for the primary prevention of IUA.Methods:The clinical data of 7 007 patients of reproductive age who underwent outpatient hysteroscopy in the Gynecological Minimally Invasive Center, Beijing Obstetrics and Gynecology Hospital from June 2018 to November 2019 were retrospectively analyzed. Patients of reproductive age with IUA without uterine fibroids and adenomyosis were selected as the IUA group (351 cases), and patients of reproductive age without uterine fibroids and adenomyosis and without IUA during the same period were selected as the control group (2 986 cases). The uterine volume was compared between the two groups. Multivariate binary logistic regression analysis was used to determine whether uterine volume was an independent factor for the occurrence of IUA. Ordinal multinomial logistic regression was used to analyze the correlation between uterine volume and menstrual volume in IUA patients. Receiver operating characteristic (ROC) curve was used to analyze the predictive value of uterine volume for IUA caused by endometrial injury.Results:(1) The uterine volume of the IUA group was significantly smaller than that of the control group (median: 44.15 vs 62.59 cm 3; Z=-15.742, P<0.001). (2) Multivariate binary logistic regression analysis showed that decreased uterine volume was an independent risk factor for IUA ( OR=0.184, 95% CI: 0.139-0.245; P<0.001). (3) The area under the ROC curve of uterine volume to predict IUA was 0.756, and the optimal cut-off value of uterine volume to predict IUA was 51.49 cm 3. (4) The risk of IUA caused by endometrial injury in patients with uterine volume≤51.49 cm 3 was 4.658 times higher than that in patients with uterine volume>51.49 cm 3 (95% CI: 3.681-5.893; P<0.001). (5) The smaller the uterine volume ( β=-0.032, 95% CI:-0.046 to -0.018; P<0.001), the more likely the IUA patients were to have menorrhagia and amenorrhea. Conclusions:Uterine volume has a certain predictive value for the occurrence of IUA caused by endometrial injury. For patients with small uterine volume, it is necessary to be alert to the occurrence of IUA caused by endometrial injury and improve the awareness of primary prevention.

Objective: To explore the correlation between different nutritional status and depressive symptoms among adolescents, so as to provide a theoretical basis for targeted improvement of nutritional status and depressive symptoms in adolescents. Methods: A total of 8 102 adolescents aged 12-17 years in Shanghai, Urumqi, Changsha and Kunming were selected by random cluster sampling. Depressive symptoms were assessed by the Center for Epidemiologic Studies Depression Scale(CES-D). Height and weight were measured. Kruskal Wallis H test, Chi square test and ordinal Logistic regression were used to analyze the relationship between nutritional status and depressive symptoms in adolescents. Results: The overall detection rate of depressive symptoms in adolescents was 25.6%, with girls (30.1%) higher than that of boys (21.1%) ( χ 2=87.60, P <0.01). There were statistically significant differences in the scores of depressive symptoms among girls with different nutritional status ( Z =8.34, P <0.05). The detectable rate of depressive symptoms increased with BMI among girls( χ 2 trend =6.04, P <0.05). After controlling for confounding factors, ordinal Logistic regression showed that the obese girls had higher risks in depressive symptoms detection compared with normal weight girls ( OR=1.45, 95%CI=1.10-1.91, P <0.05). Conclusion The nutritional status of girls is better than boys, but the prevalence of depressive symptoms is higher than boys. The risk of depressive symptoms in girls increases with BMI.

Objective: To explore the relationship between adolescents physical fitness and depressive symptoms, and to provide reference for the early prevention and intervention of depressive symptoms and improvement of physical fitness in Chinese adolescents. Methods: From September to December 2021, a total of 8 102 adolescents were selected by random cluster sampling method in Shanghai, Urumqi, Changsha and Kunming. The Center for Epidemiologic Studies Depression Scale(CES-D) was used to investigate the depressive symptoms, and completed grip strength, standing long jump, 50 m running, modified sitting forward flexion, 20 s repeated traverse, 30 s sit ups, 20 m round trip running (20 m SRT) test. χ 2 test, Goodman Kruskal Gamma and Logistic regression analysis were used to analyze the relationship between physical fitness index(PFI) and depressive symptoms. Results: The overall detection rate of depressive symptoms in adolescents with high level PFI was 23.4%, and the detection rate of low level adolescents was 26.3%, with a statistically significant difference ( χ 2=6.73, P =0.01). There was a significant positive correlation between PFI and depressive symptoms in the high school group ( G=0.09, P <0.05) and the boy group ( G=0.12, P < 0.05 ), and there was no significant association between PFI and depressive symptoms in the junior high school group and the girl group ( P >0.05). After adjusting for gender and age in the Logistic regression model, compared with those with high PFI, the risk of depressive symptoms in those with low PFI was 1.18 times (95% CI =1.05-1.33). Conclusion There is a correlation between physical fitness and depressive symptoms in adolescents. Adolescents with low PFI are at higher risk of developing depressive symptoms than those with high PFI.

Objective: To explore the correlation between non suicidal self injury(NSSI) behaviors and depressive symptoms in adolescents and to provide a theoretical basis for improvement of adolescent physical and mental health. Methods: A total of 8 102 adolescents aged 12-17 years were selected by random cluster sampling method in Shanghai, Urumqi, Changsha and Kunming, using the Center for Epidemiologic Studies Depression Scale (CES-D) and the Adolescent Non Suicidal Self Injurious Behavior Assessment Questionnaire. Depressive symptoms and the occurrence of NSSI behaviors were assessed. The relationship between NSSI behaviors and depressive symptoms was analyzed using Chi square test, one way analysis and Logistic regression analysis. Results: The overall detection rate of NSSI in adolescents, 24.6%, with a significantly lower detection rate in boys (23.1%) than in girls (26.2%) ( χ 2=10.97, P <0.05), and 24.7%, 24.6% in the middle school and high school segments, respectively, but the difference was not statistically significant ( χ 2=0.01, P >0.05). The overall detection rate of adolescent depressive symptoms was 49.7 % in the group with NSSI and 17.7% in the group without NSSI, with statistically significant differences ( χ 2=808.80, P < 0.01 ). The detection rates of adolescent depressive symptoms in the group with NSSI (male:44.0%, female:54.7%, middle school:49.6%, high school:49.8%) and the group without NSSI (male:14.2%, female:21.4%, middle school:14.3%, high school: 21.0 %) were statistically significant by sex and age groups ( χ 2=385.58, 412.44, 520.60, 313.78, P ＜0.01). Logistic regression models, after adjusting for gender and age, the risk for depressive symptoms was 2.65 times (95% CI =2.27-3.09) and 7.28 times (95% CI = 6.34- 8.37) more frequently in adolescents with episodic self injurious behavior and frequent self injurious behavior, respectively, compared to those without self injurious behavior. The association between NSSI status and depressive symptoms did not show sex differences ( P >0.05). Conclusion Adolescent NSSI behavior is positively associated with depressive symptoms, the attention should be paid to adolescent physical and mental health to reduce the occurrence of NSSI.