Local Excitation of Kagome Spin Ice Magnetism Seen by Scanning Tunneling Microscopy.

The kagome spin ice can host frustrated magnetic excitations by flipping its local spin. Under an inelastic tunneling condition, the tip in a scanning tunneling microscope can flip the local spin, and we apply this technique to kagome metal HoAgGe with a long-range ordered spin ice ground state. Away from defects, we discover a pair of pronounced dips in the local tunneling spectrum at symmetrical bias voltages with negative intensity values, serving as a striking inelastic tunneling signal. This signal disappears above the spin ice formation temperature and has a dependence on the magnetic fields, demonstrating its intimate relation with the spin ice magnetism. We provide a two-level spin-flip model to explain the tunneling dips considering the spin ice magnetism under spin-orbit coupling. Our results uncover a local emergent excitation of spin ice magnetism in a kagome metal, suggesting that local electrical field induced spin flip climbs over a barrier caused by spin-orbital locking.

[Clinical analysis of 102 cases of labor induction in the third trimester on twin pregnancy].

Objective: To investigate the clinical characteristics of induced labor in twin pregnancy and the related factors of induced labor failure. Methods: The clinical data of twin pregnant women who underwent induced labor in Peking University Third Hospital from January 2016 to December 2022 were retrospectively analyzed. According to whether they had labor or not after induction, pregnant women were divided into the success group (pregnant women who had labor after induction, 72 cases) and the failure group (pregnant women who did not have labor after induction, 30 cases). Logistic regression was used to analyze the related factors of induction failure in twin pregnant women. Results: The parity and cervical Bishop score in the failure group were significantly lower than those in the success group, while the proportion of dichorionic diamniotic twins, assisted reproductive technology pregnancy and cervical Bishop score <6, postpartum hospital stay and total hospital stay in the failure group were significantly higher than those in the success group (all P<0.05). The proportion of induced labor by artificial rupture of membranes ± oxytocin intravenous infusion in the success group was 72.2% (52/72), which was significantly higher than that in the failure group (46.7%, 14/30; P=0.030). There were no significant differences between the two groups in the gestational age at delivery, the incidence of severe postpartum hemorrhage and blood transfusion, the amount of postpartum hemorrhage, the neonatal weight of two fetuses, the incidence of neonatal asphyxia, and the proportion of neonates admitted to the neonatal intensive care unit (all P>0.05). There were no severe perineal laceration and hysterectomy in all pregnant women. Multivariate logistic regression analysis showed that primipara (OR=3.064, 95%CI: 1.112-8.443; P=0.030) and cervical Bishop score <6 (OR=5.208, 95%CI: 2.008-13.508; P=0.001) were the independent risk factors for induction failure in twin pregnancy. Conclusions: Elective induction of labor in twin pregnancy is safe and feasible. It is helpful to improve the success rate of induction of labor by strictly grasping the timing and indications of termination of pregnancy, choosing the appropriate method of induction according to the condition of the cervix, and actively promoting cervical ripening.

[Changes of cardiac structure and function in pregnant women with different types of hypertensive disorders in pregnancy and their influencing factors].

Objective: To analyze the changes in cardiac structure and function in women with different types of hypertensive disorders in pregnancy (HDP) and explore their influencing factors. Methods: A total of 1 967 pregnant women diagnosed with HDP who delivered at Peking University Third Hospital from January 1, 2014 to April 15, 2022 were included in the study. They were categorized into four groups based on specific HDP diagnoses: gestational hypertension (506 cases, 25.7%), pre-eclampsia (589 cases, 29.9%), pregnancy complicated with chronic hypertension (332 cases, 16.9%) and chronic hypertension with pre-eclampsia (540 cases, 27.5%). Differences in cardiac structure and function among four groups were retrospectively analyzed. Cardiac structure indicators included left atrial diameter (LAD), left atrial area (LAA), right atrial area (RAA), left ventricular end-diastolic diameter (LVEDD), interventricular septal thickness (IVST), left ventricular posterior wall thickness (LVPWT), systolic function indicators included left ventricular ejection fraction (LVEF), lateral systolic mitral annular velocity (Sm), diastolic function indicators included peak early diastolic mitral in flow velocity (E)/peak late diastolic mitral in flow velocity (A), and E/peak early diastolic myocardial velocity of the lateral mitral annulus early diastolic velocity (Em). Influencing factors on cardiac structure and function were analyzed using generalized linear regression. Influencing factors were assessed by generalized linear regression. Results: (1) General clinical data: the differences in age, gestational week at delivery, blood pressure, proportion of diabetes, and length of hospital stay were statistically significant among four different HDP types (all P<0.05). (2) Compared with pregnant women with pregnancy complicated with chronic hypertension, pre-eclampsia, and gestational hypertension, those with chronic hypertension with pre-eclampsia had larger LAD, LAA, RAA and LVEDD (all P<0.001), thicker IVST and LVPWT (all P<0.001), and reduced left ventricular diastolic function (E/A, lateral Em, E/Em) and systolic function (lateral Sm; all P<0.001). Pregnant women with gestational hypertension had the least changes in cardiac structure and function. Compared with pregnant women with pre-eclampsia, those with pregnancy complicated with chronic hypertension had smaller RAA (P<0.001) and lower E/A (P<0.001), with no significant difference in other indicators (all P>0.05). (3) Chronic hypertension with pre-eclampsia, pregnancy complicated with chronic hypertension, and pre-eclampsia were associated with larger LAD, LAA, and LVEDD, and lower lateral Em (all P<0.05). Conclusions: Different types of HDP are associated with distinct changes in cardiac structure and function. Chronic hypertension with pre-eclampsia demonstrates the most pronounced alterations, followed by pre-eclampsia and pregnancy complicated with chronic hypertension, and gestational hypertension showed the least changes.

[Effects of dexamethasone on short-term and long-term outcomes in late preterm infants with twin pregnancy: an observational study].

Objective: To investigate the effect of prenatal dexamethasone on short-term outcomes and long-term neurological development in late preterm infants with twin pregnancy. Methods: A total of 315 pregnant women with twin pregnancy and their preterm infants who delivered in Peking University Third Hospital from January 2019 to December 2022 were retrospectively analyzed. The clinical data of pregnant women and preterm infants were collected. They were divided into non-medication group (93 pregnant women and 186 preterm infants), medication after 34 weeks group (123 pregnant women and 246 preterm infants), and medication before 34 weeks group (99 pregnant women and 198 preterm infants). Short-term outcomes of preterm infants were analyzed, including the incidence of neonatal respiratory distress syndrome (NRDS), wet lung, hypoglycemia, neonatal septicemia, intraventricular hemorrhage (IVH), bronchopulmonary dysplasia (BPD) and neonatal necrotizing enterocolitis (NEC). "Ages and Stages Questionnaire-Third Edition (ASQ-3) scale" was used to follow up the late neurological development of preterm infants at the corrected age of 6-54 months, and the level of neurological development was compared. Results: (1) General conditions: the gestational age at delivery in the non-medication group [36.1 weeks (35.6, 36.6 weeks)] was later than that in the medication after 34 weeks group [36.1 weeks (35.2, 36.4 weeks)] and medication before 34 weeks group [35.2 weeks (34.2, 36.2 weeks)] groups, and the differences were statistically significant (all P<0.05). After correcting for gestational age, there was no significant difference in birth weight among the three groups (H=3.808, P=0.149). There were no significant differences in gender and the proportion of small for gestational age among the three groups (all P>0.05). (2) Short-term outcome: the incidence of wet lung was 7.0% (13/186), 11.0% (27/246) and 16.2% (32/198) in the non-medication group, medication after 34 weeks group and medication before 34 weeks group, respectively, and the difference was statistically significant (P=0.018). There were no significant differences in the incidence rates of NRDS, hypoglycemia, sepsis, IVH, BPD, and NEC among the three groups (all P>0.05). Logistic regression analysis with gestational age and newborn birth weight as confounding factors showed that early gestational age (OR=0.884, 95%CI: 0.837-0.933, P<0.001) and increased incidence of selective intrauterine growth restriction type I (OR=2.967, 95%CI: 1.153-7.639, P=0.024) could both lead to an increased incidence of wet lung. (3) Long-term outcomes: a total of 109 pregnant women completed the follow-up, and 218 preterm infants with a corrected age of 6-54 months at the end of follow-up were enrolled, including 86 cases in the non-medication group, 66 cases in the medication after 34 weeks group, and 66 cases in the medication before 34 weeks group. There were no significant differences in the scores of communication, gross motor, fine motor, problem solving and personal-social among the three groups (all P>0.05). Conclusion: Prenatal administration of a single course of dexamethasone does not affect the neonatal birth weight and short-term outcomes of twin late preterm infants, and has no adverse effect on the neurological development of twin late preterm infants with a corrected age of 6-54 months.

[Clinical and genetic analysis of tyrosine hydroxylase deficiency of six cases].

The clinical and molecular genetic data of 6 patients with genetically confirmed tyrosine hydroxylase deficiency(THD) diagnosed in Department of Neurology, Qilu Hospital of Shandong University from March 2017 to February 2022 were retrospectively collected and analyzed. The 6 patients were from 5 families. Among them, 5 patients had persistent or paroxysmal abnormal walking posture, 4 patients had dystonia of head and face, including spasm of perioral and oculopharyngeal muscles, hyperactivity, and binocular upvision, 4 patients showed obvious morning light and evening heavy phenomenon, 2 patients had postural tremor of limbs, 2 patients had psychomotor retardation from childhood, 1 patient only had limb and cervical muscle weakness, 1 patient had epileptic seizures. Of the 6 patients, only 1 was adult-onset, and the rest were child-onset. Four patients had good response to low-dose dopa preparation, 2 patients from the same family had poor response to dopamine treatment, requiring extremely low dose initiation and multi-frequency titration treatment. However, the long-term treatment effect was poor with obvious abnormalities. Gene testing of 5 families revealed 8 mutations in the TH gene, with c.698G>A (p.R233H) being the hot spot mutation site. The clinical manifestations of THD are complex. Besides paroxysmal or persistent dystonia, it can also be accompanied by eye movement crisis, muscle weakness, epilepsy, and delayed mental and motor development. Most patients respond well to low-dose dopamine preparations, but a small number of patients require titration treatment with extremely low-dose dopamine preparations, and the long-term effect is not satisfactory.

[Outcome analysis of pregnancy termination and expectant treatment in pregnant women with suspected invasive placenta accreta spectrum disorders in the second trimester].

Objective: To investigate the maternal and fetal outcomes of expectant treatment and early termination of pregnancy in pregnant women with suspected invasive placenta accreta spectrum disorders (PAS) in the second trimester. Methods: A retrospective cohort study was performed on 51 pregnant women with suspected invasive PAS (ultrasound score ≥10) evaluated by ultrasound with gestational age <26 weeks and confirmed as invasive PAS by intraoperative findings or postoperative pathology in Peking University Third Hospital from January 2015 to January 2022. According to the informed choice of pregnant women and their families, they were divided into expectant treatment group (37 cases) and mid-term termination group (14 cases). The general clinical data and outcome indexes of the two groups were analyzed by χ2 test, Mann-Whitney U rank sum test, logistic regression and linear regression. Results: (1) General clinical data: among 51 pregnant women who were assessed as suspected invasive PAS by ultrasonography in the second trimester, invasive PAS was finally diagnosed by intraoperative findings and postoperative pathology, among which 46 cases (90%) were placenta percreta and 5 cases (10%) were placenta increta. (2) Outcome indicators: univariate analysis showed that there were no statistically significant differences in the intraoperative blood loss (median: 2 200 vs 2 150 ml), the proportion of blood loss >1 500 ml [73% (27/37) vs 9/14], the hysterectomy rate [62% (23/37) vs 8/14], the rate of intensive care unit (ICU) admission [78% (29/37) vs 9/14] between the expectant treatment group and the mid-term termination group (all P>0.05). Multivariate analysis showed that the rate of intraoperative blood loss >1 500 ml (aOR=0.481, 95%CI: 0.017-13.958; P=0.670), hysterectomy (aOR=0.264, 95%CI: 0.011-6.569, P=0.417) and ICU admission (aOR=1.327, 95%CI: 0.048-36.882, P=0.867) between the two groups showed no statistical differences. (3) Outcome analysis: all 37 cases in the expectant treatment group had live births and no early neonatal death. Five pregnant women (14%, 5/37) in the expectant treatment group underwent emergency cesarean section in the course of expectant treatment. In the mid-term termination group, all pregnancies were terminated by operation, including 9 cases of hysterectomy and 5 cases of placental hysterectomy. There was 1 fetal survival (gestational age of termination: 27+4 weeks) and 13 fetal death in the mid-term termination group. Conclusions: Pregnant women who are diagnosed as suspected invasive PAS, especially those with placenta percreta, have the risk of uterine rupture and emergency surgery in the course of expectant treatment. However, early termination of pregnancy does not reduce the risk of intraoperative blood loss and hysterectomy.

[Association between maternal plasma one-carbon biomarkers during pregnancy and fetal growth in twin pregnancies].

Objective: To characterize the relationship between the levels of plasma methyl donor and related metabolites (including choline, betaine, methionine, dimethylglycine and homocysteine) and fetal growth in twin pregnancies. Methods: A hospital-based cohort study was used to collect clinical data of 92 pregnant women with twin pregnancies and their fetuses who were admitted to Peking University Third Hospital from March 2017 to January 2018. Fasting blood was collected from the pregnant women with twin pregnancies (median gestational age: 18.9 weeks). The levels of methyl donors and related metabolites in plasma were quantitatively analyzed by high-performance liquid chromatography combined with mass spectrometry. The generalized estimation equation was used to analyze the relationship between maternal plasma methyl donors and related metabolites levels and neonatal outcomes of twins, and the generalized additive mixed model was used to analyze the relationship between maternal plasma methyl donors and related metabolites levels and fetal growth ultrasound indicators. Results: (1) General clinical data: of the 92 women with twin pregnancies, 66 cases (72%) were dichorionic diamniotic (DCDA) twin pregnancies, and 26 cases (28%) were monochorionic diamniotic (MCDA) twin pregnancies. The comparison of the levels of five plasma methyl donors and related metabolites in twin pregnancies with different basic characteristics showed that the median levels of plasma choline and betaine in pregnant women ≥35 years old were higher than those in pregnant women <35 years old, and the differences were statistically significant (all P<0.05). (2) Correlation between plasma methyl donor and related metabolites levels and neonatal growth indicators: after adjusting for confounding factors, plasma homocysteine level in pregnant women with twins was significantly negatively correlated with neonatal birth weight (ß=-47.9, 95%CI:-94.3- -1.6; P=0.043). Elevated methionine level was significantly associated with decreased risks of small for gestational age infants (SGA; OR=0.5, 95%CI: 0.3-0.9; P=0.021) and low birth weight infants (OR=0.6, 95%CI: 0.4-0.9; P=0.020). Increased homocysteine level was associated with increased risks of SGA (OR=1.5, 95%CI: 1.0-2.2; P=0.029) and inconsistent growth in twin fetuses (OR=1.9, 95%CI: 1.0-3.7; P=0.049). (3) Correlation between the levels of plasma methyl donors and related metabolites and intrauterine growth indicators of twins pregnancies: for every 1 standard deviation increase in plasma choline level in pregnant women with twin pregnancies, fetal head circumference, abdominal circumference, femoral length and estimated fetal weight in the second trimester increased by 1.9 mm, 2.6 mm, 0.5 mm and 20.1 g, respectively, and biparietal diameter, abdominal circumference and estimated fetal weight increased by 0.7 mm, 3.0 mm and 38.4 g in the third trimester, respectively, and the differences were statistically significant (all P<0.05). (4) Relationship between plasma methyl donor and related metabolites levels in pregnant women with different chorionicity and neonatal birth weight and length: the negative correlation between plasma homocysteine level and neonatal birth weight was mainly found in DCDA twin pregnancy (ß=-65.9, 95%CI:-110.6- -21.1; P=0.004). The levels of choline, betaine and dimethylglycine in plasma of MCDA twin pregnancy were significantly correlated with the birth weight and length of newborns (all P<0.05). Conclusion: Homocysteine level is associated with low birth weight in twins, methionine is associated with decreased risk of SGA, and choline is associated with fetal growth in the second and third trimesters of pregnancy.

[Analysis on the household secondary attack rates of the SARS-CoV-2 Delta variant and the associated factors].

Objective: To evaluate the household secondary attack rates of the SARS-CoV-2 Delta variant and the associated factors. Methods: A COVID-19 outbreak caused by the Delta variant occurred in Nanjing in July 2021. A total of 235 cases with current addresses in Nanjing were reported from 171 households. The subjects in this study were selected from household close contact(s) of infected cases. The information on household index cases and their contacts were collected, and the household secondary attack rate (HSAR) and the risk factors were analyzed by the multi-factor logistic regression model. Results: A total of 234 cases of household close contacts and 64 household secondary cases were reported from 103 households, and the HSAR was 27.4% (64/234, 95%CI:22.0% to 33.4%). The proportions of household size for 2 to 3, 4 to 5, and 6 to 9 were 64.1% (66), 26.2% (27) and 9.7% (10), respectively. A total of 35 cases of household cluster outbreaks were reported (35/103, 34.0%). The number of the first case in the household (FCH) was 103 and males accounted for 27.2% (28 cases), with the median age (Q1, Q3) of 49 (9, 56). The number of household close contacts was 234 and males accounted for 59.0% (138 cases), with the median age (Q1, Q3) of 42 (20, 55) and the median exposure period (Q1, Q3) of 3 (1, 3) days. The multi-factor logistic regression model showed that the higher HSAR was observed in the FCH with the features of airport staff (OR=2.913, 95%CI:1.469-5.774), detection from home quarantine screening (OR=6.795, 95%CI:1.761-26.219) and detection from mass screening (OR=4.239, 95%CI:1.098-16.368). Meanwhile, higher HSAR was observed in cases with longer household exposure (OR=1.221, 95%CI:1.040-1.432), non-vaccination (OR=2.963, 95%CI:1.288-6.813) and incomplete vaccinations (OR=2.842, 95%CI:0.925-8.731). Conclusion: The generation interval of the Delta variant is shortened, and the ability of transmission within the household is enhanced. In the outbreak in Nanjing, the associated factors of HSAR are occupation, detection route, vaccination and exposure period.

[The short-term and long-term prognostic analysis in patients with chronic total occlusion acute non-ST segment elevation myocardial infarction].

Objectives: To investigate the clinical impacts of chronic total occlusion (CTO) in acute non-ST segment elevation myocardial infarction (NSTEMI) patients underwent primary percutaneous coronary intervention (PCI). Methods: A total of 2 271 acute NSTEMI patients underwent primary PCI from China Acute Myocardial Infarction Registry were enrolled in this study and divided into the CTO group and the non-CTO group according to the angiography. The primary endpoint was in-hospital mortality and mortality during a 2-year follow-up. The secondary endpoint was major adverse cardiovascular events (MACE) including revascularization, death, re-myocardial infarction, heart failure readmission, stroke and major bleeding. Results: Thirteen-point four percent of the total acute NSTEMI patients had concurrent CTO. In-hospital mortality (3.6% vs. 1.4%, P<0.01) and 2-year mortality (9.0% vs. 5.1%, P<0.01) were significantly higher in the CTO group than those in the non-CTO group, respectively. Multiple regression analyses showed that chronic obstructive pulmonary disease (HR 7.28, 95%CI 1.50-35.35, P=0.01) was an independent risk factor of in-hospital mortality, and advanced age (HR 1.04, 95%CI 1.01-1.07, P<0.01), and low levels of ejection fraction (HR 0.95, 95%CI 0.93-0.98, P<0.01) were independent risk factors of 2-year mortality. CTO (HR1.67, 95%CI 1.10-2.54, P=0.02) was an independent risk factor of revascularization, but not a risk factor of mortality. Conclusions: Although acute NSTEMI patients concurrent with CTO had higher mortality, CTO was only an independent risk factor of revascularization, but not of mortality. Advanced age and low levels of ejection fraction were independent risk factors of long-term death among acute NSTEMI patients.

[Infective endocarditis in pregnancy: A case report].

Infective endocarditis in pregnancy is extremely rare in clinical practice. Guidelines addressing prophylaxis and management of infective endocarditis do not extensively deal with concomitant pregnancy, and case reports on infective endocarditis are scarce. Due to increased blood volume and hemodynamic changes in late pregnancy, endocardial neoplasms are easy to fall off and cause systemic or pulmonary embolism, respiratory, cardiac arrest and sudden death may occur in pregnant women, the fetus can suffer from intrauterine distress and stillbirth at any time, leading to adverse outcomes for pregnant women and fetuses. The disease is dangerous and difficult to treat, which seriously threatens the lives of mothers and babies. Early diagnosis and reasonable treatment can effectively improve the prognosis of patients. The most important method for the treatment of infective endocarditis requires early, adequate, long-term and combined antibiotic therapy. Moreover, surgical controversies regarding indication and timing of treatment exist, especially in pregnancy. In terms of the timing of termination of pregnancy, the timing of cardiac surgery, and the method of surgery, individualized programs must be adopted. A pregnant woman with 30+5 weeks of gestation is reported. She was admitted to hospital due to intermittent chest tightness, suffocation and fever, with grade Ⅲ cardiac insufficiency. Imaging revealed large mitral valve vegetation, 22.0 mm×4.1 mm and 22.0 mm×5.1 mm, respectively, and severe valve regurgitation. Mitral valve perforation was more likely, blood culture suggested Staphylococcus epidermidis infection, after antibiotic conservative treatment, the effect was poor. After the joint consultation including cardiology, neonatology, interventional vascular surgery, anesthesiology, and obstetrics, the combined operation of obstetrics and cardiac surgery was performed in time. The heart was blocked for 60 minutes, the bleeding was 1 200 mL, the newborn was mildly asphyxiated after birth, and the birth weight was 1 890 g. Nine days after the operation, the patient was discharged from the hospital, and the newborn was discharged with the weight of 2 020 g. Critical cases like this require a thorough weighing of risks and benefits followed by swift action to protect the mother and her unborn child. An optimal outcome in a challenging case like this greatly depends on effective interdisciplinary communication, informed consent of the patient, and concerted action among the specialists involved.

[Clinical features of vaginal trial delivery in twin pregnancy and factors related with failure].

Objective: To investigate the case characteristics and factors related with failure of vaginal trial delivery in twin pregnancy. Methods: A retrospective analysis was performed on the clinical data of patients with twin pregnancy who underwent vaginal trial delivery in Peking University Third Hospital from January 2016 to June 2021. There were 109 cases in the successful group (vaginal delivery of both fetuses) and 28 cases in the failed group (cesarean delivery of one or all fetuses), the differences between the two groups were compared and the related factors of vaginal trial failure in twin pregnancy were analyzed. Results: There was no significant difference in age between the two groups[(32.4±3.8) years vs (31.3±3.3) years, P=0.163].The proportion of conception through assisted reproductive technology and induced labor in the successful group was significantly lower than that in the failed group(36.7% vs 60.7%, P<0.05;35.8% vs 60.7%, P<0.05). The average gestational age [(35.5±1.9) weeks vs (36.7±2.1) weeks, P<0.05], the body weight of the first fetus[ (2 328.4±431.9) g vs (2 585.7±443.9) g, P<0.05], the body weight of the second fetus [(2 286.2±434.8) g vs (2 531.8±574.8) g, P<0.05] and the sum of the body weight of the two fetuses[(4 614.6±801.9) g vs (5 117.5±916.1) g, P<0.05] in the successful group were significantly lower than those of the failure group. Multivariate analysis showed that assisted fertility technique (OR=2.878, 95%CI:1.167-7.099) and the sum of the body weight of the two fetus ≥4 735g (OR=4.304, 95%CI:1.659-11.165) were independent risk factors for vaginal trial failure of twin pregnancy. Conclusions: Vaginal trial delivery in twin pregnancy is relatively safe. Vaginal delivery should be carefully selected for patients with twin pregnancy who concepted through assisted reproductive technology and the sum of the body weight of the two fetus ≥4 735g.

[Clinical risk factors of cesarean scar pregnancies].

Objective: To explore the risk factors related to cesarean scar pregnancies (CSP). Methods: Among the patients during July 2016 to June 2021 in Peking University Third Hospital, 596 cases of CSP patients were included as study group, and 1 192 cases of intrauterine pregnancy(IUP) women with history of cesarean section(s) were chosen as control group through stratified sampling according to the civil year of previous cesarean section matched with CSP group. The correlation between the general situation of patients, the history of gravidity and parity, the history of surgeries in uterine cavity and the previous cesarean section and the occurrence of CSP was explored through multivariate logistic regression analysis. Results: The current age of 596 CSP patients was (34.6±4.4) years, and that of 1 192 IUP patients was (35.6±3.6) years (P<0.001). Multivariate logistic regression analysis showed that the following factors may increase the risk of CSP: age<35 years old (OR=2.306, 95%CI: 1.774-2.998), history of medical abortion (OR=1.629, 95%CI 1.102-2.407), pregnancy interval<2 years from the last cesarean section (OR=2.147, 95%CI: 1.237-3.726), pregnancy interval ≥8 years from the last cesarean section (OR=1.474, 95%CI: 1.110-1.957), history of surgeries in uterine cavity before the last cesarean section (OR=2.558, 95%CI: 1.809-3.615), history of surgeries in uterine cavity after the last cesarean section (OR=8.020, 95%CI: 5.966-10.781), previous cesarean delivery ≥2 times (OR=14.051, 95%CI: 9.699-20.356) and history of previous cesarean sections before labor (OR=2.683, 95%CI: 1.930-3.731)(all P<0.05). Conclusions: The occurrence of CSP is related to the age of patients, the history of medical abortion, pregnancy interval, the history of surgeries in uterine cavity and the previous cesarean section, among which previous cesarean delivery ≥2 times and history of surgeries in uterine cavity after the last cesarean section are the strongly associated risk factors.

[Analysis of China's influenza vaccine application policy based on the macro model of the health system].

This article uses the analysis framework of the macro model of the health system to analyze the influenza vaccine policy documents issued by the state and governments at all levels from three perspectives: structure, process and results, and provides a scientific basis for improving the application strategy of influenza vaccine. It is suggested that on the basis of continuing to strengthen publicity, mobilization and organizational guarantee, measures to promote the application of influenza vaccine in China by exploring multi-channel financing mechanisms, combining the experience of new crown vaccination to improve the convenience of influenza vaccination, and scientifically setting vaccination rate targets, improve preparedness for an influenza pandemic.

[Longitudinal correlation between cell phone use and sleep quality in college students].

Objective: To investigate the current situation of cell phone use and sleep quality among college students, establish a sleep quality trajectory model and explore the influence of cell phone use on the sleep quality trajectory. Methods: Based on data from the College Student Behavior and Health Cohort Study 2019-2020, a latent class growth modeling was used to establish a sleep quality trajectory model among college students. The baseline influencing factors of sleep quality trajectories among college students were analyzed by χ2 test, and the effects of cell phone use on sleep quality trajectories were analyzed by binary logistic regression. Results: A total of 1 092 college students were included in the analysis. The detection rates of cell phone use and poor sleep quality were 24.5% and 13.3%. Latent class growth model identified two groups of sleep quality trend trajactories: an improved sleep quality group (86.0%) and a decreased sleep quality group (14.0%). The result of binary logistic regression showed that the cell phone use was a risk factor of sleep quality trajectories. Conclusion: The cell phone use during college period could increase the risk of poor sleep quality. Targeted intervention measures about cell phone use should be adopted to improve the sleep quality among college students.

[Ocular biometry of infants and young children with congenital cataract].

Objective: To understand the developmental characteristics of early ocular biological parameters in patients with congenital cataract. Methods: Retrospective case series study. The ocular biometry data such as the axial length, corneal curvature, anterior chamber depth and central corneal thickness of 169 patients under 3 years old who were diagnosed with congenital cataract in Eye Hospital of Wenzhou Medical University (Hangzhou Branch) from June 2016 to June 2020 were reviewed, and they were analyzed by 3 age groups. There were 87, 41, and 41 patients in three age groups, 1 to 6 months, 7 to 12 months, and 13 to 36 months, respectively; 108 patients with bilateral affected eyes and 61 patients with unilateral affected eyes were included; 84 patients with partial opacity lens and 85 patients with total opacity lens were included. The right eyes of the patients with bilateral congenital cataract were selected for analysis. Statistical analysis of ocular biological parameters between groups was performed using the independent samples t-test and paired samples t-test. Statistical analysis of the relationship between age in months and biological parameters was performed using the Pearson's correlation test. Results: The axial length at the age of 1 to 6 months in the affected eyes of patients with bilateral cataract was (17.59±1.19) mm, it was shorter than the affected eyes of patients with unilateral cataract [(18.18±1.34) mm], and the axial length in the affected eyes of patients with unilateral cataract were shorter than the healthy eyes [(19.01±0.93) mm]. At the age of 7 to 12 months, the axial length in the affected eyes of patients with unilateral cataract [(19.89±0.74) mm] was shorter than the healthy eyes [(20.48±0.43) mm]. The differences were statistically significant (t=-2.06, -5.62, -3.47, all P<0.05). The axial length in the affected eyes with partial opacity at the age of 1 to 6 months was shorter than those with total opacity [(17.43±1.14) mm vs. (18.06±1.29) mm; t=-2.38, P=0.020]. The difference in axial length (affected eyes vs. healthy eyes) was significantly correlated with the age in months in partial cataract (r=0.53, P=0.001). The corneal curvature in the affected eyes of patients with unilateral cataract was flatter than the healthy eyes at the age of 7 to 12 months [(42.41±1.82) D vs. (43.19±1.96) D; t=-2.29, P=0.038], but was steeper at the age of 13 to 36 months [(43.36±2.32) D vs. (42.55±1.88) D; t=2.17, P=0.043]. The anterior chamber depth in the affected eyes of patients with unilateral cataract was less than the healthy eyes at the age of 1 to 6 months [(2.44±0.37) mm vs. (2.58±0.33) mm; t=-2.08, P=0.048].The central corneal thickness in the affected eyes of patients with unilateral cataract was thicker than the healthy eyes both at the age of 1 to 6 months and 7 to 12 months [(555.26±46.95) µm vs. (541.85±40.78) µm, (542.93±27.63) µm vs. (530.93±30.36) µm; t=3.82, 2.26; P=0.001, 0.040]. Conclusions: Congenital cataracts maybe affect the early development of axial length, corneal curvature, anterior chamber depth and central corneal thickness. The degree of lens opacity maybe affecte the early axial length development. The axial length in eyes with partial opacity can be shorter than those with total opacity before the age of 6 months, and thereafter gradually outnumbered the latter.

[The effect of occupational stress on anxiety of nursing staff in a third-grade general hospital and mediating effect of job burnout].

Objective: To explore the mediating effect of job burnout of nursing staff in clinical departments on occupational stress and anxiety, and to provide scientific basis for the formulation of intervention measures to relieve anxiety. Methods: From November 2020 to January 2021, a cross-sectional survey was conducted to investigate the basic situation, occupational stress, job burnout and anxiety of 653 nursing staff in a third class A general hospital in Hebei Province. Spearman rank correlation was used to analyze the relationship between occupational stress, job burnout and anxiety, stepwise regression and mediating effect model were used to verify the mediating effect of job burnout on the relationship between occupational stress and anxiety. Results: 551 valid questionnaires were collected with effective recovery of 84.38%. The incidence of high occupational stress was 68.06% (375/551) , the incidence of job burnout was 63.70% (351/551) [high, moderate and moderate were 11.07% (61/551) and 52.63% (290/551) respectively], and the incidence of anxiety was 55.72% (307/551) [mild, moderate and severe were 38.11% (210/551) , 8.53% (47/551) and 9.08% (50/551) respectively]. Occupational stress was positively correlated with job burnout and anxiety (r=0.545, 0.479) , and job burnout was positively correlated with anxiety (r=0.542, P<0.05) . The mediating effect analysis showed that occupational stress had a statistically significant effect on anxiety (c=0.509, P<0.001) , and the mediating effect of job burnout on the relationship between occupational stress and anxiety accounted for 44.99% of the total effect. Conclusion: The anxiety level of the nursing staff in this third-class A general hospital was relatively high. Job burnout has a mediating effect between occupational stress and anxiety, and anxiety of nursing staff can be alleviated by reducing occupational stress or job burnout.

[Thyroid function of first-trimester twin pregnant women and its association with preterm delivery].

OBJECTIVE: To describe the thyroid function abnormality of first-trimester twin pregnant women according to different references, and to explore its association with preterm delivery. METHODS: Participants, first-trimester twin pregnant women, were recruited at Peking University Third Hospital from March 2017 to February 2020. The thyroid hormone reference for ordinary adults identified on the assay kits by Siemens incorporation, thyroid hormone reference specifically for singleton pregnancy established previously, and thyroid hormone reference specifically for twin pregnancy established previously were used in the description of hypothyroidism and hyperthyroidism for first-trimester twin pregnant women. Thyroid autoantibody reference identified on the assay kits by Siemens incorporation was used in the description of positive thyroid autoantibody. Multivariable log-binomial regression was conducted to examine the association between thyroid function and preterm delivery, in which normal pregnant women according to the three references and normal pregnant women according to twin pregnancy reference accompanied with negative thyroid autoantibody were taken as control respectively. RESULTS: A total of 570 twin pregnant women were finally included. Rates of hypothyroidism according to the three references were 1.2%, 1.6% and 3.5%, respectively. Rates of hyperthyroidism according to the three references were 32.6%, 18.1% and 1.1%, respectively. After adjustment for potential confounding factors, risk of preterm delivery significantly increased in pregnant women with hyperthyroidism according to the twin specific pregnancy reference [adjusted relative risk (ARR)=1.41, 95%CI: 1.14-1.75], while no significant increase was found in those with normal thyroid function according to the twin specific pregnancy reference but hyperthyroidism according to the singleton specific pregnancy reference (ARR=1.00, 95%CI: 0.81-1.25) and in those with hyperthyroidism purely according to the ordinary adult reference (ARR=1.06, 95%CI: 0.85-1.32), compared with those normal according to all the references. Risks of preterm delivery almost significantly or significantly increased in pregnant women with hypothyroidism according to the ordinary adult or singleton specific pregnancy reference (ARR=1.40, 95%CI: 0.88-2.22) and those with hypothyroidism according to the twin specific pregnancy reference (ARR=1.53, 95%CI: 1.03-2.28). Overall analysis of thyroid function according to the twin specific pregnancy reference and thyroid autoantibody showed that risks of preterm delivery almost significantly or significantly increased in pregnant women with simple hypothyroidism (ARR=1.46, 95%CI: 0.93-2.27), simple positive thyroid autoantibody (ARR=1.32, 95%CI: 1.15-1.52), and hypothyroidism accompanied with positive thyroid autoantibody (ARR=1.78, 95%CI: 1.30-2.44), compared with those normal according to the twin specific pregnancy reference with negative thyroid autoantibody. CONCLUSION: The ordinary adult reference and that of singleton pregnancy may lead to under-diagnosis of hypothyroidism and over-diagnosis of hyperthyroidism in first-trimester twin pregnant women. Compared with pregnant women with normal thyroid function, those missed in the diagnosis of hypothyroidism were at a higher risk of preterm delivery, while those over-diagnosed as hyperthyroidism had a similar risk of preterm delivery, indicating a need to develop and generalize twin-pregnancy-specific reference on common indicators of thyroid function. Moreover, the thyroid autoantibody should be taken into consideration in the prenatal diagnosis and treatment to twin pregnant women with hypothyroidism.

[Diagnosis, treatment and outcome of adnexal torsion at different gestational weeks during pregnancy].

Objective: To investigate the clinical characteristics, diagnosis, treatment and outcome of adnexal torsion at different gestational weeks during pregnancy. Methods: A retrospective analysis was conducted of the clinical data of 24 pregnancy patients with adnexal torsion, aged 21-38 (30.6±4.4) years old, who were admitted and delivered in Peking University Third Hospital from 2015 to 2019. According to the gestational age, all patients were divided into two groups:<28 weeks group (11cases) and ≥28 weeks group (13 cases), to compare the intergroup differences in clinical characteristics, treatment and outcome, and the differences of clinical data and outcome between two groups were compared. Results: The proportion of patients with twin pregnancy and assisted reproductive technology in the<28 weeks group was significantly higher than that in the ≥28 weeks group (5/11 vs 1/13, 8/11 vs 1/13, P<0.05). No significant differences between the two groups were recorded in terms of the size of the adnexal mass, the cycles of torsion and the duration from onset to operation. Compared with the≥28 weeks group, the adnexal removal rate of the<28 weeks group was lower (3/11 vs 6/13), but the difference was not statistically significant. The proportion of blood flow signals of ultrasound before operation, cases undergoing laparoscopic surgery and cases whose pathological findings were physiological cysts in the<28 weeks group were significantly higher than that in the ≥28 weeks group (8/11 vs 4/13, 8/11 vs 0, 8/11vs 4/13; P<0.05). Concerning the pregnancy outcomes, there was no difference in the mode of delivery, the delivery gestational age and the body weight of newborns between the two groups. Conclusions: The patients with adnexal torsion prior to 28 weeks(<28 weeks)of pregnancy were more likely to be conceived by assisted reproductive technologies, and the etiology was more likely to be ovarian physiological cysts. Both laparoscopy and laparotomy were safe and effective in the treatment of adnexal torsion with good outcome for mother and infant in the study.

[Association of hyperuricemia-induced renal damage with sirtuin 1 and endothelial nitric oxide synthase in rats].

Objective: To investigate the association of hyperuricemia-induced renal damage with sirtuin 1 (SIRT1) and endothelial nitric oxide synthase (eNOS) in rats. Methods: Using the random number table method, 32 Sprague-Dawley rats were randomly divided into 4 groups: control group, model A group (the model was generated using oxonic acid potassium salt alone), model B group (hyperuricemia model was generated using oxonic acid potassium salt combined with uric acid) and resveratrol group, with 8 rats in each group. The experiment lasted 12 weeks. Serum uric acid and cystatin C levels were monitored regularly. In week 12, serum creatinine and urea nitrogen levels were measured, and the kidneys were extracted. The expression of SIRT1 and eNOS in renal tissues was measured and determined by immunohistochemistry, quantitative reverse-transcription polymerase chain reaction (RT-qPCR) and western blotting. Immunohistochemistry of alpha-smooth muscle actin combined with Masson staining was employed to evaluate the degree of renal fibrosis, and pathological changes were observed based on hematoxylin and eosin staining. Results: In week 12, the uric acid levels in both the model A and model B groups were higher than those in the control group [(316±43) µmol/L, (297±40) µmol/L vs (118±44) µmol/L, both P<0.05]. The levels of cystatin C in the model A, model B, and resveratrol groups were all higher than those in the control group [(156±20) ng/ml, (143±29) ng/ml, (128±26) ng/ml vs (62±18) ng/ml, all P<0.05]. Creatinine levels were higher in the model A and model B groups than those in the control group [(68.5±10.3) µmol/L, (64.5±13.9) µmol/L vs (43.2±10.6) µmol/L, both P<0.05]. The levels of uric acid, cystatin C and creatinine in the resveratrol group were lower than those in the model A group (all P<0.05). Immunohistochemistry, RT-qPCR, and Western blotting for renal SIRT1 and eNOS showed that the expression in the model A and model B groups was inhibited, while the expression in the resveratrol group was not significantly inhibited, compared with that in the control group. Microscopically, obvious abnormalities were not found in the renal tissue of the control group. Renal inflammatory cell aggregation and edema occurred, and interstitial fibrosis was obvious in both the model A and model B groups, while these lesions in the resveratrol group were significantly improved. Conclusions: Hyperuricemia may cause renal injury by inhibiting the expression of SIRT1 and eNOS.

[Effect of placental vascular distribution on residual anastomoses after fetoscopic laser surgery for twin to twin transfusion syndrome].

Objective: To investigate the effect of placental vascular distribution on residual anastomoses (RA) after fetoscopic laser occlusion of chorioangiopagous ressels (FLOC) for twin to twin transfusion syndrome (TTTS). Methods: A total of 57 cases of TTTS after laser surgery were retrospectively analyzed from April 2014 to April 2019 in Peking University Third Hospital. The patients were divided into RA group (24 cases) and non-RA group (33 cases) according to whether RA occurred in the placenta after laser surgery. The clinical characteristics, perioperative conditions, pregnancy outcomes and placental structure characteristics of the two groups were compared. Multivariate logistic regression was used to analyze the risk factors of placental vascular distribution for RA. The RA group was further divided into non-remission group and remission group, and the placental characteristics and pregnancy outcome of the two groups were compared. Results: (1)General clinical characteristics: the age, application of assisted reproductive technology, incidence of gestational hypertension, gestational diabetes mellitus, preoperative maximum amniotic fluid depth of the donor and recipient twins, Quintero stage and placental position of TTTS patients in the two groups were compared respectively, and there were no statistically significant differences (all P>0.05).The gestational age of patients received FLOC in the RA group was significantly higher than the non-RA group [(23.0±2.4) vs (21.9±2.7) weeks, P=0.033].(2) Perioperative conditions and pregnancy outcomes: the delivery gestational age of the RA group was significantly lower than that of the non-RA group (median:31.8 vs 34.4 weeks, P=0.002);The newborn birth weight in the RA group was significantly lower than that in the non-RA group [(1 648±597) and (2 013±481) g, P=0.003].The birthweight difference in the RA group was significantly higher than that in the non-RA group (median:0.30 vs 0.11, P=0.005). (3) The placental structure and the risk factors influencing RA happened: the differences in the proportion of four types of placental vascular distribution in the RA group and non-RA group were different significantly (χ²=10.214, P=0.012), with a detail of parallel type 29% (7/24) and 3% (1/33), staggered type 58% (14/24) and 76% (25/33), hybrid 8% (2/24) and 21% (7/33), monoamniotic membrane type 4% (1/24) and 0 respectively. Multivariate logistic regression analysis showed that parallel placental vascular distribution was an independent risk factor for RA after FLOC (OR=24.5, 95%CI 1.7-336.2, P=0.017). (4) Placental characteristics and pregnancy outcomes in the remission and non-remission groups of the RA group: the incidence of three kinds of anastomoses, the total number, total diameter and proportion of RA, and the placental territory discordance ratio were compared between the two groups, and there were no statistical significances (P>0.05);The birth weight difference ratio in the non-remission group was higher than that in the remission group (median:0.41 vs 0.28, P=0.036). Conclusion: The parallel type of placental vascular distribution may be an independent risk factor for RA in TTTS after laser surgery.