[Changes of uterine morphology and endometrial T2 signal intensity in the fibrotic repair secondary to endometrial injury].

Objective: To investigate the value of uterine morphological parameters and endometrial T2 signal intensity (T2-SI) in evaluating the degree of the fibrotic repair secondary to endometrial injury. Methods: From Sep. 2018 to Feb. 2023, this study prospectively enrolled 29 patients with fibrotic repair secondary to severe endometrial injury (severe group), 17 patients with fibrotic repair secondary to mild to moderate endometrial injury (mild to moderate group), and 40 healthy women of reproductive age (control group) in Nanjing Drum Tower Hospital. The length of uterine cavity (LUC), length of cervix and isthmus (LCI), width of upper uterine cavity (WUUC) and width of lower uterine cavity (WLUC) were measured using magnetic resonance imaging. T2-SI of endometrium and subcutaneous fat of buttocks were measured, and endometrial normalized T2-SI (nT2-SI; T2-SI of endometrium/T2-SI of subcutaneous fat of buttocks) was calculated. Statistical analyses of data were performed using one-way analysis of variance, Mann-Whitney U test, intraclass correlation coefficient, Spearman rho test, area under the receiver operating characteristic curve (AUC). Results: LUC, WUUC, WLUC and endometrial nT2-SI of severe group [(19.7±3.5) mm, (26.9±6.4) mm, (7.9±1.4) mm, 0.73±0.11, respectively] were significantly lower than those of the control group (all P<0.01), while LCI and WUUC/LUC [(51.3±7.3) mm and 1.38±0.34] were significantly higher than those of the control group (all P<0.001). LUC and WLUC of severe group were significantly lower than those of mild to moderate group [(32.4±5.1) mm and (8.8±1.2) mm; all P<0.05], while LCI and WUUC/LUC were significantly higher than those of mild to moderate group [(41.8±8.6) mm and 0.94±0.16; all P<0.001]. LUC and endometrial nT2-SI of mild to moderate group were significantly lower than those of the control group [ (32.4±5.1) vs (35.3±3.5) mm, 0.68±0.13 vs 0.80±0.12; all P<0.01]. LUC, WUUC, WLUC and endometrial nT2-SI were significantly negatively correlated to the degree of the fibrotic repair secondary to endometrial injury (Spearman rho:-0.794, -0.441, -0.471 and -0.316, respectively; all P<0.05), while LCI and WUUC/LUC were significantly positively correlated to the degree of the fibrotic repair secondary to endometrial injury (Spearman rho: 0.481 and 0.674, respectively; all P<0.05). LUC and WUUC/LUC showed high value in distinguishing severe group from the control group or mild to moderate group (all AUC>0.9, all P<0.001). Conclusion: As noninvasive and quantitative biomarkers, uterine morphological parameters and endometrial nT2-SI could evaluate the degree of the fibrotic repair secondary to endometrial injury.

The natural course of otitis media with effusion in infants who failed universal newborn hearing screening: a retrospective cohort study.

OBJECTIVES: To analyse the natural course of infants with otitis media with effusion who failed universal newborn hearing screening and to explore the appropriate observation period. METHODS: This retrospective cohort analysis included infants with otitis media with effusion who failed universal newborn hearing screening every 3 months for 12 months. RESULTS: The average recovery time of the 155 infants was 7.08 ± 0.32 months after diagnosis. Multivariate Cox regression analysis confirmed that frequent reflux, maxillofacial deformities and initial hearing status were independent factors affecting recovery. Moreover, the cumulative recovery of most infants with mild hearing loss and infants with moderate hearing loss accompanied by frequent reflux was significantly higher at six months after diagnosis than at three months. CONCLUSION: For most infants with mild hearing loss, as well as those with moderate hearing loss accompanied by frequent reflux, the observation period can be extended to six months after diagnosis.

[The purchase behavior of prepackaged food and its determinants among primary and middle school students in 6 provinces of China].

Objective: To examine the purchase behaviors of prepackaged food and its determinants among primary and middle school students in 6 provinces of China. Methods: A multi-stage sampling strategy was adopted to select 2 499 primary and middle school students and their parents from the eastern region of China(Beijing, Jiangsu Province, Guangdong Province), the northeast region(Heilongjiang Province), the central region(Henan Province) and the western region(Sichuan Province) from July 2020 to March 2021. Socio-demographic characteristics of students and their parents, eating-related behaviors and the purchase behaviors of prepackaged food of students, and parents' attitudes towards students' eating behavior were collected through questionnaire towards students and their parents. The χ² test was conducted to compare the purchase behaviors in different groups of students, and multivariate logistic stepwise regression analysis was used to analyze the determinants among primary and middle school students. Results: The age of 2 499 participants was(12.7±2.5) years. There were 1 272(50.9%) females and 1 279(51.2%) middle school students. About 1 404(56.2%) students bought prepackaged food. The top 6 prepackaged foods bought at least once a week were milk and dairy products(74.6%), baked food(58.7%), beverages(42.8%), puffed food(40.8%), chocolate and candy(39.8%), and nuts and dried fruits(37.5%). The multivariate logistic regression model analysis results showed that compared with primary school students, rural students, non-boarding students, students who did not like snacks and students whose parents paid attention to their children eating snacks, middle school students(OR=3.36, 95%CI:2.73-4.12), urban students(OR=1.33, 95%CI:1.11-1.61), boarding students(OR=2.15, 95%CI:1.66-2.79), students who liked snacks(OR=2.01, 95%CI:1.66-2.43), students whose parents did not pay attention to their children eating snacks(OR=1.27, 95%CI:1.05-1.54) were more likely to buy prepackaged food by themselves. Compared with students whose parents had education level of junior high school and below, students whose parents had education level of undergraduate and above(OR=0.70, 95%CI:0.53-0.92) were less likely to buy prepackaged food by themselves. Compared with students whose family monthly income was less than 5 000 yuan, students whose family monthly income was over 10 000 yuan(OR=0.67, 95%CI:0.52-0.87) were less likely to buy prepackaged food by themselves. Conclusion: Many primary and middle school students buy prepackaged food by themselves in 6 provinces of China. Individual characteristics such as grade, place of residence, boarding status, as well as family environment such as parents' education level, monthly income and concern about children eating snacks are the influencing factors of purchasing prepackaged food.

[Analysis of epidemiological characteristics of pulmonary tuberculosis patients in Fengtai District, Beijing City from 2011 to 2021].

Objective: To analyze the epidemiological characteristics of pulmonary tuberculosis (PTB) in Fengtai District from 2011 to 2021. Methods: A retrospective study was conducted, the data of PTB patients in Fengtai District from 2011 to 2021 were collected in Chinese disease prevention and Control Information System, which included etiological classification, gender, age, occupation, onset time, demographic information etc. the epidemiological characteristics of reported PTB patients was analysis. Results: A total of 10 342 cases of PTB were reported from 2011 to 2021 in Fengtai District, with an average annual reported incidence rate of 42.87/ 100 000. The incidence rate was the highest in 2012(75.89/100 000), and significantly declined from 2013, which declined to 29.70/100 000 in 2017. It showed a slow rise from 2018 to 2021. The difference was statistically significant (χ2=1 471.77,P<0.001).There were 2 975 cases of etiologic positive PTB from 2011 to 2021, and 76 cases of Rifampicin-resistant PTB from 2017 to 2021. The ratio of male cases to female was 1.75, the average annual incidence rate of male (53.94/100 000) was higher, than female(31.57/100 000).(χ2=704.01,P<0.001). Among all age groups, 25-29 years group, 20-24 years group and 30-34 years group had the highest proportion, which were 1 506 cases (14.56%) , 1 292 cases (12.49%) and 1 024 cases (9.90%) respectively. The average annual incidence rate was the lowest in the group less than 10 years old (1.43/100 000), and the highest in the group 85 years old and over (195.20/100 000), the difference was statistically significant(χ2=3164.24, P<0.001). The top occupations from high to low were housework and unemployment (2 917 cases, 28.21%), retirees (2 308 cases, 22.32%), workers (1 047 cases, 10.12%), cadres and staff (950 cases, 9.19%), farmers (860 cases, 8.32%), business services (698 cases, 6.75%), teachers and students (455 cases, 4.40%). Conclusion: From 2011 to 2021, the incidence rate of PTB was decreased from 2012 to 2017, and slowly increased lately in Fengtai District. The epidemiological characteristics of PTB vary in different age and gender.

[Association between the awareness of Nutrition Facts Panel and prepackaged food purchase behavior among residents].

Objective: To explore the association between the cognition of Nutrition Facts Panel and prepackaged food purchase behavior among residents in six provinces in China. Methods: Using a multi-stage sampling method, 3 002 adults aged 18-70 were selected from the western region (Sichuan), eastern region (Guangdong, Jiangsu, Beijing), central region (Henan), and northeastern region (Heilongjiang) of China from July 2020 to March 2021. Socio-demographic characteristics of participants and their cognition of Nutrition Facts Panel and prepackaged food purchase behavior were collected through questionnaire. A multivariate binary logistic regression model was used to analyze the association between cognition of Nutrition Facts Panel and prepackaged food purchase behavior. Results: The age of 3 002 subjects was (42.3±13.4) years, among which 63.8% (1 914) were female, 66.7% knew the Nutrition Facts Panel, 49.8% would read it when purchasing, 30.7% could understand it, and 56.6% (1 699) bought prepackaged food more than once a week. The results of multivariate analysis showed that after adjusting for relevant confounding factors, compared with the participants knowing but not reading the Nutrition Facts Panel, the group knowing and reading was more likely to buy 11 types of prepackaged food at least once a week (all P<0.05). Compared with the participants reading but not understanding the Nutrition Facts Panel, the group reading and understanding was less likely to buy 11 types of prepackaged food at least once a week (all P<0.05). Conclusion: There was a correlation between cognition of Nutrition Facts Panel and prepackaged food purchase behavior among residents.

[Investigation and analysis of the implementation status of "Diagnosis and therapy guideline of preterm birth (2014)"].

Objective: To understand the actual situation of the implementation of "Diagnosis and therapy guideline of preterm birth（2014）", "Guideline" for short, by front-line obstetricians, and to provide reference for the further update and supplement of the "Guideline". Methods: This study designed a structured questionnaire for the prominent problems in the prevention and treatment of preterm birth, which was determined by the expert team drafting the "Guideline". In October to November 2021, a cross-sectional survey was conducted among obstetricians, including members of the Perinatal Medicine Branch of Jiangsu Medical Association and the Obstetrics Subgroup,Chinese society of Obstetrics and Gynecology, Chinese Medical Association, on the implementation status of the "Guideline". The recommendations of the "Guideline" were used as standard answers to determine the implementation rate. A total of 328 valid questionnaires were collected. The total score of the questionnaire was 12 points. The questionnaire was divided into low executive ability group (<7 points) and high executive ability group (≥7 points) with a score of 7 as the threshold value, and the differences in baseline information such as hospital grade and professional title between the two groups were compared. Results: The score of 328 obstetricians was (7.6±1.6) points, including 250 (76.2%, 250/328) in the high execution group and 78 (23.8%, 78/328) in the low execution group. The execution rates of "the use of uterine contraction inhibitors for short courses"[97.0% (318/328)], "late umbilical cord breakage after birth of premature infants"[87.8% (288/328)] and "should preterm patients with intact membranes be treated with antibiotics"[86.6% (284/328)] were all over 80%, indicating good implementation. Multiple logistic regression analysis showed that hospital grade and professional title were independent factors influencing the performance of the "Guideline"(all P<0.05), and secondary hospitals had lower scores and worse execution than tertiary hospitals (OR=0.42, 95%CI: 0.23-0.77; P=0.005). Senior titles had higher scores and better execution than junior titles (OR=5.33, 95%CI: 2.35-12.07; P<0.001). When answering the question "gestational week at which premature infants could survive in your hospital", only 3.4% (11/328) answered 22 weeks, and 44.5% (146/328) answered 28 weeks, accounted for the highest proportion. The gestational week of surviving premature infants in tertiary hospitals was earlier than that in secondary hospitals (P<0.05). The gestational week of surviving premature infants answered by senior titles was earlier than that of junior titles (P<0.05). Conclusions: Obstetricians generally have a good implementation of the "Guideline", and their understanding of some recommended clauses in the guidelines needs to be improved. In the future, training of primary hospitals and physicians with junior titles should be strengthened.

[The preference for Front-of-Pack Labeling and its association with the understanding of Nutrition Facts Panel among residents aged 18 to 70: results of a survey in 6 provinces of China].

Objective: To investigate the preference for Front-of-Pack Labeling (FOP) and its association with the understanding of the Nutrition Facts Panel among Chinese residents. Methods: A multi-stage sampling strategy was adopted to select 3 002 people aged between 18 and 70 years old from the eastern region of China (Beijing, Jiangsu Province, Guangdong Province), the northeast region (Heilongjiang Province), the central region (Henan Province) and the western region (Sichuan Province) from July 2020 to March 2021. Socio-demographic characteristics of participants and their understanding of the Nutrition Facts Panel and preference for FOP were collected. The χ² test was conducted to compare the preference for FOP in different groups of population, and multivariate logistic regression was used to analyze the association between the preference for FOP and the understanding of the Nutrition Facts Panel. Results: The mean age of 3 002 participants was (42.3±13.4) years, of which 1 914 (63.8%) were females and 69.3% could not understand the Nutrition Facts Panel. About 2 458 respondents (81.9%) suggested that FOP could be promoted. The top three nutrients that should be labeled were sugar (68.4%), salt (68.2%) and total fat (62.4%). The number of participants who believed that the Multiple Traffic Lights (MTL) could be easier to help consumers to quickly choose healthy food, attract attention and provide the most needed information was 1 064 (35.4%), 1 026 (34.2%) and 1 140 (38.0%), respectively. The multivariate logistic regression analysis showed that, compared with the Guideline Daily Amount (GDA) system, participants who could not understand the Nutrition Facts Panel preferred (1) Nutri-Score, Warning labels, and Health logos: Smart Choice in terms of"Which format of FOP could quickly help you choose food more easily?"[OR (95%CI): 2.21 (1.62-3.02), 1.64 (1.22-2.22), 1.79 (1.31-2.45), respectively]; (2) Nutri-Score, Warning labels, and Health logos: Smart Choice in terms of"Which format of FOP could attract your attention the most?"[OR (95%CI): 2.62 (1.92-3.59), 1.96 (1.45-2.66), 2.25 (1.66-3.04), respectively]; and (3) Nutri-Score, Warning labels, and Health logos: Smart Choice in terms of"Which format of FOP could provide you with the most needed information?"[OR (95%CI): 2.33 (1.70-3.21), 2.21 (1.66-2.95), 2.01 (1.50-2.71), respectively]. Conclusion: The residents from six provinces in China have a supportive attitude towards FOP. The interpretive FOP with color information, specific nutrient information and summary indicator can be launched. The nutrition information of sugar, salt and total fat could be prioritized to be labeled on the FOP.

[Study on surface electromyography characteristics of erector spinae muscles at different spinal anteversion angles of the scrapers].

Objective: To simulate and evaluate the scraping and grinding work of workers with different spinal anteversion angles, and to explore the effects of different anteversion angles on the erector spinae muscles of scrapers. Methods: In November 2019, 16 male college student volunteers were recruited to simulate workers' scraping and grinding work. The parameters were 25°, 15 times/min, 15°, 30 times/min, 5°, 60 times/min respectively. The surface electromyography (sEMG) was used to collect the electromyographic signals of the erector spinae muscles, and the surface electromyographic characteristics of the erector spinae muscles were evaluated with Borg Scale. Results: There were significant differences between the maximum voluntary contraction percentage (MVE%) of the left and right erector spinae muscles groups in the three groups with different spinal anteversion angles (F(left)=13.41, P(left)<0.001; F(right)=4.74, P(right)=0.005) , and the EMG amplitude was higher at 25°, 15 times/min. At 15°, 30 times/min, MVE% of the left side was significantly higher than that of the right side (t=2.58, P=0.021) . There was significant difference in the mean power frequency (MPF) of the right erector spinae muscle in the three groups (F=9.42, P<0.001) , but there was no significant difference in the MPF of the left erector spinae muscle (F=0.30, P=0.823) . The fitting line showed that the left erector spinae muscle showed a downward trend at 5°, 60 times/min (t=-5.39, P=0.012) . Conclusion: Scrapers are less likely to be fatigued when the posture is 15°, 30 times/min, but they are more likely to be fatigued when working at 5°, 60 times/min.

[Association between gestational blood pressure and pregnancy induced hypertension or pre-eclampsia].

Objective: To construct the gestational-age-specific blood pressure curve and percentile blood pressure values of pregnant women in Jiangsu Province, and to explore the clinic significance of the blood pressure changes in women whose blood pressure was less than 140/90 mmHg (1 mmHg=0.133 kPa) in each trimester and eventually developed pregnancy induced hypertension (PIH) or pre-eclampsia (PE). Methods: A prospective longitudinal cohort during pregnancy was built. Singleton pregnant women in the first trimester (11-13+6 weeks) were recruited from July 2017 to September 2020 in Nanjing Drum Tower Hospital, and were followed up in the second trimester (19-23+6 weeks), the third trimester (30-33+6 weeks) and approaching the expected date of delivery (35-38+6 weeks). The Viewpoint 6.0 software was used to record pregnancy-related information. The blood pressure was measured by standard methods in our clinic. Least mean square (LMS) function was performed to fit the gestational-age-specific blood pressure curve and percentile blood pressure values were calculated at every follow-up time point. Logistic regression was applied to calculate the OR for the groups with blood pressure ≥95th percentile (P95). Results: There were 3 728 singleton pregnant women invited in this study, including 3 490 normal pregnant women (93.62%, 3 490/3 728), and 238 pregnant women with PIH or PE (6.38%, 238/3 728). Gestational-age-specific blood pressure curve showed that systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) decreased in the second trimester, compared with those in the first and the third trimester, however the fluctuation of blood pressure was low, but regardless of the gestational age, P95 of SBP, DBP and MAP increased by 14, 11 and 11 mmHg respectively, compared with 50th percentile (P50). In the first trimester, the risk of developing PIH or PE finally in pregnant women with blood pressure ≥P95 was 4.36-fold (95%CI: 2.99-6.35) for SBP than women with SBP

[Comparison of diagnostic performance of thyroid autoantibodies and high-resolution ultrasound in euthyroid Hashimoto's thyroiditis].

Objective: To compare the diagnostic performance of thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TgAb) and high-resolution ultrasound (HRUS) in euthyroid Hashimoto's thyroiditis (HT). Methods: From January 2016 to January 2019, patients with complete data of preoperative thyroid function, TPOAb, TgAb and HRUS who had undergone thyroid surgery treatment at the First Affiliated Hospital with Nanjing Medical University were reviewed. The diagnostic value of different diagnostic methods was compared using histopathology (HP) examination result as the gold standard. Results: The data of 792 patients (217 males and 575 females) was retrospectively collected. The M(Q1,Q3)of patients' age was 41(32,52)years and the range was 16-75 years. With HP as the diagnostic gold standard, TPOAb exhibited similar sensitivity (59.3% vs 61.2%, P=0.752), accuracy (85.0% vs 83.6%, P=0.379), area under the receiver operating characteristic curve (AUC) (0.767 vs 0.764, P=0.886) and higher specificity (94.2% vs 91.6%, P=0.033) when compared with TgAb in diagnosing euthyroid HT. They both exhibited a higher sensitivity (59.3% vs 44.5%, P = 0.002; 61.2% vs 44.5%, P<0.001), accuracy (85.0% vs 79.7%, P = 0.001; 83.6% vs 79.7%, P = 0.013) and AUC (0.767 vs 0.684, P<0.001; 0.764 vs 0.684, P<0.001) than HRUS. Compared with each method alone, the sensitivity and AUC of TPOAb combined with TgAb or HRUS were improved. The combination of three methods showed the greatest sensitivity. Concordance analysis demonstrated that TPOAb and HP had a moderate agreement (Kappa=0.580, 95%CI:0.513-0.647,P<0.001). Conclusions: The combination of thyroid antibodies, TPOAb and TgAb, can improve sensitivity, accuracy and AUC of diagnosis in euthyroid Hashimoto's thyroiditis. The two antibodies combined with HRUS exhibited the highest diagnostic performance. Elevated TPOAb showed moderate diagnostic consistency with histopathologic evidence of HT.

LncRNA MIR503HG regulated cell viability, metastasis and apoptosis of cervical cancer via miR-191/CEBPB axis.

OBJECTIVE: The long non-coding RNA MIR503 host gene (MIR503HG) plays a role in suppressing or promoting cancer in many types of human malignant tumors. The role of MIR503HG in cervical cancer is still unknown. PATIENTS AND METHODS: The expression level of MIR503HG in cervical cancer tissues and cell lines was accessed using quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) assay. The Cell Counting Kit-8 (CCK-8) assay and flow cytometric analysis were performed to assess cell proliferation and apoptosis in cervical cancer. The nude mouse xenograft experiment was used to examine the ability of MIR503HG in tumor formation. In our study, we found that the expression of MIR503HG was significantly reduced in cervical cancer tissues and cell lines. In vitro studies have shown that MIR503HG inhibited cell proliferation and invasion, and enhanced cell apoptosis in cervical cancer through the miR-191/CEBPB axis. MIR503HG regulated the expression of miR-191 via directly binding to miR-191. RESULTS: The expression of MIR503HG had a negative correlation with miR-191 expression in cervical cancer tissues. MiR-191 regulated the expression of CEBPB by directly targeting 3'-UTR of CEBPB mRNA. Overexpression of MIR503HG inhibited cell proliferation, invasion and apoptosis in vitro, and inhibited tumor growth in vivo. CONCLUSIONS: MIR503HG plays a role in suppressing tumors in cervical cancer and is a long-term non-coding RNA.

[Characteristics and related factors of plantar pressure in the chronic ankle instability individuals].

OBJECTIVE: To analyze characteristics and related factors of the plantar pressure during the level walking and single leg standing in the chronic ankle instability (CAI) individuals. METHODS: From April 2019, 75 CAI individuals and 40 healthy individuals were enrolled in this study. Both of the static and dynamic plantar pressure were measured during six times level walking and three times single leg standing testing. The data including peak force, time to peak force in various foot contact areas and the time to boundary (TTB) and velocity of center of pressure (COP) were measured and compared between the affected side and the unaffected side and between the CAI cases and the healthy individuals. The correlations between the plantar pressure and the gender, Beighton score, affected side and body mass index (BMI) were analyzed. RESULTS: The characteristics of plantar pressure distribution in the CAI individuals included: (1) During the level walking, the affected side showed the similar pressure contribution as the unaffected side (P>0.05). While compared with healthy individuals, there was a significantly higher peak force in the 5th metatarsal area (t=-3.86, P=0.03) of the affected side, lower peak force in the 1st (t=2.99, P=0.02), 2nd metatarsal head areas (t=2.09, P=0.01) of the affected side, medial hindfoot areas of both sides (affected, t=2.33, P=0.01; unaffected, t=3.74, P=0.02) and toes areass of both sides (affected, t=2.23, P=0.01; unaffected, t=3.28, P=0.02) and a delay to peak force in the 4th metatarsal head area (t=3.33, P=0.01) of the affected side. (2) During the single leg standing, the CAI individuals showed significantly worse balance control in the anterior/posterior direction (P < 0.05) and lateral/medial direction (P < 0.05) compared with the healthy controls, and the affected side had more severe balance control deficit in the lateral/medial direction (P < 0.05). (3) The women (P < 0.05) and the individuals with higher Beighton scores (P < 0.05) showed worse balance control deficit in the lateral/medial direction. CONCLUSION: CAI individuals showed significantly a more lateral shifted plantar distribution during the level walking compared with the healthy individuals and the tendency was worse on the affected sides, and showed worse balance control in the anterior/posterior direction and lateral/medial direction during the single leg standing. The women and those with generalized ligament laxity showed significantly worse balance control.

[Effects of interpregnancy interval on pregnancy outcomes of subsequent pregnancy: a multicenter retrospective study].

Objective: To explore the effects of interpregnancy interval (IPI) on pregnancy outcomes of subsequent pregnancy. Methods: A multicenter retrospective study was conducted in 21 hospitals in China. Information of age, height, pre-pregnancy weight, IPI, history of diseases, complications of pregnancy, gestational age of delivery, delivery mode, and pregnancy outcomes of the participants were collected by consulting medical records of pregnant women who had two consecutive deliveries in the same hospital during 2011 to 2018. The participants were divided into 4 groups according to IPI:<18 months, 18-23 months, 24-59 months and ≥60 months. According to the WHO's recommendation, with the IPI of 24-59 months group as a reference, to the effects of IPI on pregnancy outcomes of subsequent pregnancy were analyzed. Stratified analysis was further carried out based on age, history of gestational diabetes mellitus (GDM), macrosomia, and premature delivery, to explore the differences in the effects of IPI on pregnancy outcomes among women with different characteristics. Results: A total of 8 026 women were included in this study. There were 423, 623, 5 512 and 1 468 participants in <18 months group, 18-23 months group, 24-59 months group and ≥60 months group, respectively. (1) The age, pre-pregnancy body mass index (BMI), history of cesarean section, GDM, gestational hypertension and cesarean section delivery rate of <18 months group, 18-23 months group, 24-59 months group and ≥60 months group were gradually increased, and the differences were statistically significant (P<0.05). (2) After adjusting for potential confounding factors, compared with women in the IPI of 24-59 months group, the risk of premature delivery, premature rupture of membranes, and oligohydramnios were increased by 42% (OR=1.42, 95%CI: 1.07-1.88, P=0.015), 46% (OR=1.46, 95%CI: 1.13-1.88, P=0.004), and 64% (OR=1.64, 95%CI: 1.13-2.38, P=0.009) respectively for women in the IPI≥60 months group. No effects of IPI on other pregnancy outcomes were found in this study (P>0.05). (3) After stratified by age and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would significantly increase the risk of oligohydramnios for women with advanced age (OR=2.87, 95%CI: 1.41-5.83, P=0.004); and <18 months could increase the risk of premature rupture of membranes for women under the age of 35 (OR=1.59, 95%CI: 1.04-2.43, P=0.032). Both the risk of premature rupture of membranes (OR=1.58, 95%CI: 1.18-2.13, P=0.002) and premature delivery (OR=1.52, 95%CI: 1.07-2.17, P=0.020) were significantly increased in the IPI≥60 months group. After stratified by history of GDM and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would lead to an increased risk of postpartum hemorrhage for women with a history of GDM (OR=5.34, 95%CI: 1.45-19.70, P=0.012) and an increased risk of premature rupture of membranes for women without a history of GDM (OR=1.44, 95%CI: 1.10-1.90, P=0.009). After stratified by history of macrosomia and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months could increase the proportion of cesarean section for women with a history of macrosomia (OR=4.11, 95%CI: 1.18-14.27, P=0.026) and the risk of premature rupture of membranes for women without a history of macrosomia (OR=1.46, 95%CI: 1.12-1.89, P=0.005). After stratified by history of premature delivery and adjusted for confounding factors, compared with women in the IPI of 24-59 months group, IPI≥60 months would significantly increase the risk of premature rupture of membranes for women without a history of premature delivery (OR=1.47, 95%CI: 1.13-1.92, P=0.004). Conclusions: Both IPI≥60 months and <18 months would increase the risk of adverse pregnancy outcomes in the subsequent pregnancy. Healthcare education and consultation should be conducted for women of reproductive age to maintain an appropriate IPI when they plan to pregnant again, to reduce the risk of adverse pregnancy outcomes in the subsequent pregnancy.

[Current status and research progress in load assessment methods for occupational low back pain].

With the development of industry, musculoskeletal disorders have become increasingly prominent, and low back pain is one of the major problems. The United States and Germany have already included it in the category of occupational diseases. Therefore, it is extremely important to determine the occupational factors affecting low back pain and evaluate the load level of workers. In this paper, combined with the existing literature, the evaluation methods of the load of low back pain were reviewed, in order to provide reference for the development of prevention strategies of low back pain from the perspective of occupational factors.

[Survey of related factors of maternal venous thromboembolism in nine hospitals of China].

Objective: To investigate and analyze disease status and risk factors of venous thromboembolism (VTE) during pregnancy and puerperium in our country. Methods: Clinical datas were collected from 575 patients diagnosed with VTE during pregnancy and puerperium and hospitalized in nine medical institutions in our country from January 1, 2015 to November 30, 2019, and retrospectively analyzed it's disease status and risk factors. Results: (1) The proportion of VTE in pregnancy and puerperium was 50.6% (291/575) and 49.4% (284/575), respectively. Four patients died, the mortality rate was 0.7% (4/575). The cause of death was pulmonary embolism. (2) The location of VTE during pregnancy and puerperium was mainly in the lower limb vascular (76.2%, 438/575), followed by pulmonary vessels (7.1%, 41/575). (3) In the risk factors of VTE, cesarean section accounted for 32.3% (186/575), maternal advance age accounted for 27.7% (159/575), braking or hospitalization during pregnancy accounted for 13.6% (78/575), other risk factors accounted for more than 5% were previous VTE, obesity, preterm birth, assistant reproductive technology conception and so on, pre-eclampsia and multiple pregnancy accounted for 4.9% (28/575) respectively. In addition, some patients with VTE did not have any of the above risk factors, and the incidence rate was as high as 23.1% (133/575). Conclusions: The occurrence of VTE during pregnancy and puerperium is related to multiple risk factors, and could lead to matemal death, It is very necessary to screen VTE risk factors for all pregnant women, to make corresponding prevention and control measures.

[Intrauterine balloon tamponade combined with temporary abdominal aortic balloon occlusion in the management of women with placenta accreta spectrum:a randomized controlled trial].

Objective: To access the effectiveness and safety of the intrauterine balloon tamponade verse gauze packing combined with temporary abdominal aortic balloon occlusion in the management of placenta accreta spectrum (PAS). Methods: This was an open-label, randomized controlled trial conducted in Nanjing Drum Tower Hospital. The patients suspected with PAS for uterine preservation surgery under the multidisciplinary team care were recruited between Aug 2015 and Jan 2018. When bleeding could not be achieved after fetus delivered, and a temporary abdominal aortic balloon occlusion and the compression sutures as needed, the women were randomly allocated 1∶1 into balloon tamponade (n=81) or gauze packing (n=80) group. The primary outcome was successful bleeding arrests by avoiding second line surgeries. The secondary outcomes included the volume of blood loss during and after cesarean section, the rate of PPH, incidence and amount of blood transfusion, hysterectomy, postpartum pain, ICU admission, need for re-laparotomy, and the length of hospital stay, readmission, and interventional radiology complications. Results: All the women [100% (81/81)] in the balloon group were obtained hemostasis without further intervention, significantly higher than 88% (70/80) in the gauze group (P=0.001). Before uterine tamponade, blood loss were 820 ml (620-1 230) ml and 850 ml (605-1 442) ml, while placenta bed were sutured in 96%（78/81, 77/80） respectively (P>0.05).The proportion of blood loss≥1 000 ml was higher in the gauze group than that in the balloon group (P=0.006). Maternal adverse events involving total blood loss, puerperal morbidity and postpartum pain occurred more frequently in the gauze group (P<0.05). The following outcome showed no statistically significant difference between the two groups: the vascular occlusion time, the dose of radiation, and interventional radiology complication (P>0.05). The median volume infused into the lower and upper balloons is 70 ml (50-100 ml) and 180 ml (100-240 ml). Conclusions: Incrauterine balloon tamponade is as effective as gauze packing in hemostasis following the placenta delivery in PAS. Compared with gauze packing, the uterine balloon tamponade is more effective.