1.Phosphatidylinositol 3-kinases Play a Suppressive Role in Electrotaxis of Dictyostelium Cells Through Akt and ERK
Xiao-Xue GE ; Rui-Da JIANG ; Xiao-Yan WANG ; Jing GAO ; Run-Chi GAO
Progress in Biochemistry and Biophysics 2024;51(3):685-695
ObjectivePhosphatidylinositol 3 kinases (PI3Ks) play an important role in cell directional movement by regulating F-actin. However, the structure and function of PI3Ks are complex. The role of PI3Ks in cell electrotaxis is not fully understood. Therefore, in this study, the model organism Dictyostelium discoideum cells were used as experimental materials to explore the role of PI3K1 and PI3K2 in electrotaxis. MethodsFirstly, PI3K1 coding gene pikA knockout mutant and PI3K2 coding gene pikB knockout mutant were constructed by CRISPR/Cas9 system. Secondly, two mutants were placed in a DC electric field with a strength of 12 V/cm and the electrotaxis were analyzed. ResultsData analysis showed that the direction index of wild-type cells in DC electric field was (0.86±0.03), while the direction index of pikA- and pikB- mutants in DC electric field was (0.95±0.02) and (0.94±0.03), respectively. In addition, the average trajectory speed of wild-type cells in the electric field was (3.34±0.08) μm/min, while the average trajectory speed of pikA- and pikB- mutants were (4.85±0.20) μm/min and (5.48±0.15) μm/min, respectively. The t test showed that there were significant differences in the directedness index and speed between the mutant and wild type. Western blot results showed that both phosphorylated Akt and phosphorylated ERK were significantly increased in pikA- and pikB- mutants. ConclusionPI3K1 and PI3K2 may inhibit the electrotaxis of Dictyostelium discoideum cells by increasing the activity of Akt and ERK.
2.Association of Cytokines with Clinical Indicators in Patients with Drug-Induced Liver Injury
Hua Wei CAO ; Ting Ting JIANG ; Ge SHEN ; Wen DENG ; Yu Shi WANG ; Yu Zi ZHANG ; Xin Xin LI ; Yao LU ; Lu ZHANG ; Yu Ru LIU ; Min CHANG ; Ling Shu WU ; Jiao Yuan GAO ; Xiao Hong HAO ; Xue Xiao CHEN ; Ping Lei HU ; Jiao Meng XU ; Wei YI ; Yao XIE ; Hui Ming LI
Biomedical and Environmental Sciences 2024;37(5):494-502
Objective To explore characteristics of clinical parameters and cytokines in patients with drug-induced liver injury(DILI)caused by different drugs and their correlation with clinical indicators. Method The study was conducted on patients who were up to Review of Uncertainties in Confidence Assessment for Medical Tests(RUCAM)scoring criteria and clinically diagnosed with DILI.Based on Chinese herbal medicine,cardiovascular drugs,non-steroidal anti-inflammatory drugs(NSAIDs),anti-infective drugs,and other drugs,patients were divided into five groups.Cytokines were measured by Luminex technology.Baseline characteristics of clinical biochemical indicators and cytokines in DILI patients and their correlation were analyzed. Results 73 patients were enrolled.Age among five groups was statistically different(P=0.032).Alanine aminotransferase(ALT)(P=0.033)and aspartate aminotransferase(AST)(P=0.007)in NSAIDs group were higher than those in chinese herbal medicine group.Interleukin-6(IL-6)and tumor necrosis factor alpha(TNF-α)in patients with Chinese herbal medicine(IL-6:P<0.001;TNF-α:P<0.001)and cardiovascular medicine(IL-6:P=0.020;TNF-α:P=0.001)were lower than those in NSAIDs group.There was a positive correlation between ALT(r=0.697,P=0.025),AST(r=0.721,P=0.019),and IL-6 in NSAIDs group. Conclusion Older age may be more prone to DILI.Patients with NSAIDs have more severe liver damage in early stages of DILI,TNF-α and IL-6 may partake the inflammatory process of DILI.
3.Expression,prognostic relevance of P4HB in glioblastoma and its biological effects on tumor cells
Guan-You HUANG ; Xiao-Hong HOU ; Xue-Cheng GE ; Hong-Chuan GAN ; Shu-Yu HAO ; Zhen WU
Medical Journal of Chinese People's Liberation Army 2024;49(4):459-467
Objective To investigate the expression of prolyl 4-hydroxylase β-polypeptide(P4HB)in glioblastoma multiforme(GBM)and its impact on clinical prognosis,as well as on the proliferation and migration of U87 cells.Methods(1)According to the Cancer Genome Atlas(TCGA)database,GTEx database and GEPIA2 database,the difference expression of P4HB in GBM and normal brain tissues were analyzed by R software.(2)A total of 52 patients with GBM who underwent surgical treatment from February 2017 to December 2019 were collected from Department of Neurosurgery,the Second People's Hospital of Guiyang.The normal brain tissues of 10 patients were selected as controls.Immunohistochemical method was used to detect the expression level of P4HB in tumor tissues and normal tissues.The Kaplan-Meier method with the log-rank test was employed for survival analysis.Receiver operating characteristic(ROC)curve was used to analyze the predictive valuable of P4HB expression in survival rate of GBM.Univariate and multivariate Cox regression analysis were used to identify the expression of P4HB and related clinicopathological factors affecting the survival and prognosis of the patients.(3)Human GBM U87 cells were randomly assigned into three groups:control group,NC-siRNA group and P4HB-siRNA group.P4HB expression was interfered with by the transfection of siRNA in P4HB-siRNA group.Real-time quantitative polymerase chain reaction(qRT-PCR)was used to detect the content of P4HB mRNA in U87 cells.Cell counting kit-8(CCK-8)and immunofluorescence assay were used to analyze the effects of P4HB on the proliferation of U87 cells.Scratch test was used to analyze the effects of P4HB on cell migration.Results The expression of P4HB was significantly upregulated in GBM tissues compared with normal brain tissues(P<0.05).The γδ T cells(r=-0.227)and follicular helper T cells(r=-0.226)were negatively correlated with the expression of P4HB,while natural killer cell(r=0.417),macrophages(r=0.374),neutrophils(r=0.344),and immature dendritic cells(r=0.263)were positively correlated with the expression of P4HB.Kaplan-Meier survival analysis showed that the progression-free survival and disease-specific survival of GBM patients with high P4HB expression were significantly lower than those with low expression(P<0.05).ROC curve showed that the area under the curve(AUC)of P4HB in predicting overall survival rate of GBM patients was 0.982,and 1-year,3-year,and 5-year survival was 0.655,0.724,0.861,respectively.The immunohistochemistry results suggested that P4HB protein was significantly highly expressed in GBM tumors.Survival analysis indicated that high expression of P4HB was associated with bad prognosis in GBM patients(P<0.05).Multivariate Cox regression analysis indicated that high expression of P4HB and TERT promoter mutations were the independent prognostic risk factors for GBM(P<0.05).Compared with control group and NC-siRNA group,the expression levels of P4HB were decreased significantly after transfected with siRNA in U87 cells of P4HB-siRNA group(P<0.01),and the proliferation ability and the wound healing rate were decreased significantly in P4HB-siRNA group(P<0.001).Conclusions P4HB is significantly highly expressed in GBM,which indicates that the prognosis of patients is poor.Knockout of P4HB could inhibit cellular proliferation and migration of GBM U87 cells.P4HB may be used as the relevant predictive marker and potential therapeutic target in GBM.
4.In Vitro Amplification of NK Cells from Feeder Layer Cells Expressing IL-21
Zhen-Zhao XU ; Xue-Hua ZHANG ; Ling-Ping ZHAO ; Gao-Hua LI ; Tian-Tian CUI ; Xiao-Ling WANG ; Xuan LI ; Ru-Ge ZANG ; Wen YUE ; Ya-Nan WANG ; Guo-Xin LI ; Jia-Fei XI
Journal of Experimental Hematology 2024;32(5):1578-1584
Objective:To investigate the effect of feeder layer cells expressing interleukin(IL)-21 on the amplification of NK cells in vitro.Methods:The K562 cell line with IL-21 expression on its membrane was constructed by electroporation,and co-cultured with NK cells after inactivation.The proliferation of NK cells was observed.The killing function of the amplified NK cells in vitro was evaluated by the lactate dehydrogenase(LDH)and interferon-γ(IFN-y)release assay.A colorectal cancer xenograft model in NOD/SCID mice was established,and a blank control group,a NK cell group and an amplified NK cell group were set up to detect the tumor killing effect of amplified NK cells in vivo.Results:K562 cells expressing IL-21 on the membrane were successfully constructed by electroporation.After co-culturing with K562 cells expressing IL-21 on the membrane for 17 days,the NK cells increased to 700 times,which showed an enhanced amplification ability compared with control group(P<0.001).In the tumor cell killing experiment in vitro,there was no significant difference in the killing activity on tumor cells between NK cells and amplified NK cells,and there was also no significant difference in mice in vivo.Conclusion:K562 cells expressing IL-21 on the membrane can significantly increase the amplification ability of NK cells in vitro,but do not affect the killing function of NK cells in vitro and in vivo.It can be used for the subsequent large-scale production of NK cells in vitro.
6.LC-MS analysis of 2-(2-phenylethyl) chromones in sodium chloride-treated suspension cells of Aquilaria sinensis.
Yu DU ; Xiao-Xue ZHANG ; Ze-Kun ZHANG ; Wen-Jing WANG ; Bei-Bei ZHANG ; Ming-Liang ZHANG ; Yang WANG ; Xiang-Yu GE ; She-Po SHI
China Journal of Chinese Materia Medica 2023;48(9):2480-2489
Qualitative and quantitative analysis of 2-(2-phenylethyl) chromones in sodium chloride(NaCl)-treated suspension cells of Aquilaria sinensis was conducted by UPLC-Q-Exactive-MS and UPLC-QQQ-MS/MS. Both analyses were performed on a Waters T3 column(2.1 mm×50 mm, 1.8 μm) with 0.1% formic acid aqueous solution(A)-acetonitrile(B) as mobile phases at gradient elution. MS data were collected by electrospray ionization in positive ion mode. Forty-seven phenylethylchromones was identified from NaCl-treated suspension cell samples of A. sinensis using UPLC-Q-Exactive-MS, including 22 flindersia-type 2-(2-phenylethyl) chromones and their glycosides, 10 5,6,7,8-tetrahydro-2-(2-phenylethyl) chromones and 15 mono-epoxy or diepoxy-5,6,7,8-tetrahydro-2-(2-phenylethyl) chromones. Additionally, 25 phenylethylchromones were quantitated by UPLC-QQQ-MS/MS. Overall, the rapid and efficient qualitative and quantitative analysis of phenylethylchromones in NaCl-treated suspension cells of A. sinensis by two LC-MS techniques, provides an important reference for the yield of phenylethylchromones in Aquilariae Lignum Resinatum using in vitro culture and other biotechnologies.
Chromones
;
Sodium Chloride
;
Chromatography, Liquid
;
Flavonoids
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Tandem Mass Spectrometry
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Thymelaeaceae
7.Status of fungal sepsis among preterm infants in 25 neonatal intensive care units of tertiary hospitals in China.
Xin Cheng CAO ; Si Yuan JIANG ; Shu Juan LI ; Jun Yan HAN ; Qi ZHOU ; Meng Meng LI ; Rui Miao BAI ; Shi Wen XIA ; Zu Ming YANG ; Jian Fang GE ; Bao Quan ZHANG ; Chuan Zhong YANG ; Jing YUAN ; Dan Dan PAN ; Jing Yun SHI ; Xue Feng HU ; Zhen Lang LIN ; Yang WANG ; Li Chun ZENG ; Yan Ping ZHU ; Qiu Fang WEI ; Yan GUO ; Ling CHEN ; Cui Qing LIU ; Shan Yu JIANG ; Xiao Ying LI ; Hui Qing SUN ; Yu Jie QI ; Ming Yan HEI ; Yun CAO
Chinese Journal of Pediatrics 2023;61(1):29-35
Objective: To analyze the prevalence and the risk factors of fungal sepsis in 25 neonatal intensive care units (NICU) among preterm infants in China, and to provide a basis for preventive strategies of fungal sepsis. Methods: This was a second-analysis of the data from the "reduction of infection in neonatal intensive care units using the evidence-based practice for improving quality" study. The current status of fungal sepsis of the 24 731 preterm infants with the gestational age of <34+0 weeks, who were admitted to 25 participating NICU within 7 days of birth between May 2015 and April 2018 were retrospectively analyzed. These preterm infants were divided into the fungal sepsis group and the without fungal sepsis group according to whether they developed fungal sepsis to analyze the incidences and the microbiology of fungal sepsis. Chi-square test was used to compare the incidences of fungal sepsis in preterm infants with different gestational ages and birth weights and in different NICU. Multivariate Logistic regression analysis was used to study the outcomes of preterm infants with fungal sepsis, which were further compared with those of preterm infants without fungal sepsis. The 144 preterm infants in the fungal sepsis group were matched with 288 preterm infants in the non-fungal sepsis group by propensity score-matched method. Univariate and multivariate Logistic regression analysis were used to analyze the risk factors of fungal sepsis. Results: In all, 166 (0.7%) of the 24 731 preterm infants developed fungal sepsis, with the gestational age of (29.7±2.0) weeks and the birth weight of (1 300±293) g. The incidence of fungal sepsis increased with decreasing gestational age and birth weight (both P<0.001). The preterm infants with gestational age of <32 weeks accounted for 87.3% (145/166). The incidence of fungal sepsis was 1.0% (117/11 438) in very preterm infants and 2.0% (28/1 401) in extremely preterm infants, and was 1.3% (103/8 060) in very low birth weight infants and 1.7% (21/1 211) in extremely low birth weight infants, respectively. There was no fungal sepsis in 3 NICU, and the incidences in the other 22 NICU ranged from 0.7% (10/1 397) to 2.9% (21/724), with significant statistical difference (P<0.001). The pathogens were mainly Candida (150/166, 90.4%), including 59 cases of Candida albicans and 91 cases of non-Candida albicans, of which Candida parapsilosis was the most common (41 cases). Fungal sepsis was independently associated with increased risk of moderate to severe bronchopulmonary dysplasia (BPD) (adjusted OR 1.52, 95%CI 1.04-2.22, P=0.030) and severe retinopathy of prematurity (ROP) (adjusted OR 2.55, 95%CI 1.12-5.80, P=0.025). Previous broad spectrum antibiotics exposure (adjusted OR=2.50, 95%CI 1.50-4.17, P<0.001), prolonged use of central line (adjusted OR=1.05, 95%CI 1.03-1.08, P<0.001) and previous total parenteral nutrition (TPN) duration (adjusted OR=1.04, 95%CI 1.02-1.06, P<0.001) were all independently associated with increasing risk of fungal sepsis. Conclusions: Candida albicans and Candida parapsilosis are the main pathogens of fungal sepsis among preterm infants in Chinese NICU. Preterm infants with fungal sepsis are at increased risk of moderate to severe BPD and severe ROP. Previous broad spectrum antibiotics exposure, prolonged use of central line and prolonged duration of TPN will increase the risk of fungal sepsis. Ongoing initiatives are needed to reduce fungal sepsis based on these risk factors.
Infant
;
Infant, Newborn
;
Humans
;
Birth Weight
;
Intensive Care Units, Neonatal
;
Retrospective Studies
;
Tertiary Care Centers
;
Infant, Extremely Low Birth Weight
;
Gestational Age
;
Infant, Extremely Premature
;
Sepsis/epidemiology*
;
Retinopathy of Prematurity/epidemiology*
;
Bronchopulmonary Dysplasia/epidemiology*
8.Safety and efficacy of the early administration of levosimendan in patients with acute non-ST-segment elevation myocardial infarction and elevated NT-proBNP levels: An Early Management Strategy of Acute Heart Failure (EMS-AHF).
Feng XU ; Yuan BIAN ; Guo Qiang ZHANG ; Lu Yao GAO ; Yu Fa LIU ; Tong Xiang LIU ; Gang LI ; Rui Xue SONG ; Li Jun SU ; Yan Ju ZHOU ; Jia Yu CUI ; Xian Liang YAN ; Fang Ming GUO ; Huan Yi ZHANG ; Qing Hui LI ; Min ZHAO ; Li Kun MA ; Bei An YOU ; Ge WANG ; Li KONG ; Jian Liang MA ; Xin Fu ZHOU ; Ze Long CHANG ; Zhen Yu TANG ; Dan Yu YU ; Kai CHENG ; Li XUE ; Xiao LI ; Jiao Jiao PANG ; Jia Li WANG ; Hai Tao ZHANG ; Xue Zhong YU ; Yu Guo CHEN
Chinese Journal of Internal Medicine 2023;62(4):374-383
Objectives: To investigated the safety and efficacy of treating patients with acute non-ST-segment elevation myocardial infarction (NSTEMI) and elevated levels of N-terminal pro-hormone B-type natriuretic peptide (NT-proBNP) with levosimendan within 24 hours of first medical contact (FMC). Methods: This multicenter, open-label, block-randomized controlled trial (NCT03189901) investigated the safety and efficacy of levosimendan as an early management strategy of acute heart failure (EMS-AHF) for patients with NSTEMI and high NT-proBNP levels. This study included 255 patients with NSTEMI and elevated NT-proBNP levels, including 142 males and 113 females with a median age of 65 (58-70) years, and were admitted in the emergency or outpatient departments at 14 medical centers in China between October 2017 and October 2021. The patients were randomly divided into a levosimendan group (n=129) and a control group (n=126). The primary outcome measure was NT-proBNP levels on day 3 of treatment and changes in the NT-proBNP levels from baseline on day 5 after randomization. The secondary outcome measures included the proportion of patients with more than 30% reduction in NT-proBNP levels from baseline, major adverse cardiovascular events (MACE) during hospitalization and at 6 months after hospitalization, safety during the treatment, and health economics indices. The measurement data parameters between groups were compared using the t-test or the non-parametric test. The count data parameters were compared between groups using the χ² test. Results: On day 3, the NT-proBNP levels in the levosimendan group were lower than the control group but were statistically insignificant [866 (455, 1 960) vs. 1 118 (459, 2 417) ng/L, Z=-1.25,P=0.21]. However, on day 5, changes in the NT-proBNP levels from baseline in the levosimendan group were significantly higher than the control group [67.6% (33.8%,82.5%)vs.54.8% (7.3%,77.9%), Z=-2.14, P=0.03]. There were no significant differences in the proportion of patients with more than 30% reduction in the NT-proBNP levels on day 5 between the levosimendan and the control groups [77.5% (100/129) vs. 69.0% (87/126), χ²=2.34, P=0.13]. Furthermore, incidences of MACE did not show any significant differences between the two groups during hospitalization [4.7% (6/129) vs. 7.1% (9/126), χ²=0.72, P=0.40] and at 6 months [14.7% (19/129) vs. 12.7% (16/126), χ²=0.22, P=0.64]. Four cardiac deaths were reported in the control group during hospitalization [0 (0/129) vs. 3.2% (4/126), P=0.06]. However, 6-month survival rates were comparable between the two groups (log-rank test, P=0.18). Moreover, adverse events or serious adverse events such as shock, ventricular fibrillation, and ventricular tachycardia were not reported in both the groups during levosimendan treatment (days 0-1). The total cost of hospitalization [34 591.00(15 527.46,59 324.80) vs. 37 144.65(16 066.90,63 919.00)yuan, Z=-0.26, P=0.80] and the total length of hospitalization [9 (8, 12) vs. 10 (7, 13) days, Z=0.72, P=0.72] were lower for patients in the levosimendan group compared to those in the control group, but did not show statistically significant differences. Conclusions: Early administration of levosimendan reduced NT-proBNP levels in NSTEMI patients with elevated NT-proBNP and did not increase the total cost and length of hospitalization, but did not significantly improve MACE during hospitalization or at 6 months.
Male
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Female
;
Humans
;
Aged
;
Natriuretic Peptide, Brain
;
Simendan/therapeutic use*
;
Non-ST Elevated Myocardial Infarction
;
Heart Failure/drug therapy*
;
Peptide Fragments
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Arrhythmias, Cardiac
;
Biomarkers
;
Prognosis
9.Ferroptosis of airway epithelial cells in asthma: current and future
Xue-mei CHEN ; Juan LIANG ; Xiu-ling SONG ; Xiao-hua LIU ; Chu-peng XUE ; Yu-ge HUANG ; Wen LI
Acta Pharmaceutica Sinica 2022;57(6):1614-1620
Ferroptosis is a novel cell death mode proposed in recent years, which is characterized by intracellular iron-dependent lipid peroxidation. Its mechanisms include lipid peroxidation, iron accumulation and the imbalance of antioxidant system. The crosstalk between ferroptosis and asthma is gradually deepening. Elucidating the specific mechanism of ferroptosis in regulating asthma is helpful to broaden the understanding of the pathology of asthma. This paper expounds the role of ferroptosis in airway epithelial cells in the occurrence and development of asthma from three perspectives: lipid peroxidation, iron accumulation and the imbalance of antioxidant system, hoping to find new targets and strategies for asthma treatment.
10.Clinical treatment outcomes and their changes in extremely preterm twins: a multicenter retrospective study in Guangdong Province, China.
Bi-Jun SHI ; Ying LI ; Fan WU ; Zhou-Shan FENG ; Qi-Liang CUI ; Chuan-Zhong YANG ; Xiao-Tong YE ; Yi-Heng DAI ; Wei-Yi LIANG ; Xiu-Zhen YE ; Jing MO ; Lu DING ; Ben-Qing WU ; Hong-Xiang CHEN ; Chi-Wang LI ; Zhe ZHANG ; Xiao RONG ; Wei SHEN ; Wei-Min HUANG ; Bing-Yan YANG ; Jun-Feng LYU ; Hui-Wen HUANG ; Le-Ying HUO ; Hong-Ping RAO ; Wen-Kang YAN ; Xue-Jun REN ; Yong YANG ; Fang-Fang WANG ; Dong LIU ; Shi-Guang DIAO ; Xiao-Yan LIU ; Qiong MENG ; Yu WANG ; Bin WANG ; Li-Juan ZHANG ; Yu-Ge HUANG ; Dang AO ; Wei-Zhong LI ; Jie-Ling CHEN ; Yan-Ling CHEN ; Wei LI ; Zhi-Feng CHEN ; Yue-Qin DING ; Xiao-Yu LI ; Yue-Fang HUANG ; Ni-Yang LIN ; Yang-Fan CAI ; Sha-Sha HAN ; Ya JIN ; Guo-Sheng LIU ; Zhong-He WAN ; Yi BAN ; Bo BAI ; Guang-Hong LI ; Yue-Xiu YAN
Chinese Journal of Contemporary Pediatrics 2022;24(1):33-40
OBJECTIVES:
To investigate the clinical treatment outcomes and the changes of the outcomes over time in extremely preterm twins in Guangdong Province, China.
METHODS:
A retrospective analysis was performed for 269 pairs of extremely preterm twins with a gestational age of <28 weeks who were admitted to the department of neonatology in 26 grade A tertiary hospitals in Guangdong Province from January 2008 to December 2017. According to the admission time, they were divided into two groups: 2008-2012 and 2013-2017. Besides, each pair of twins was divided into the heavier infant and the lighter infant subgroups according to birth weight. The perinatal data of mothers and hospitalization data of neonates were collected. The survival rate of twins and the incidence rate of complications were compared between the 2008-2012 and 2013-2017 groups.
RESULTS:
Compared with the 2008-2012 group, the 2013-2017 group (both the heavier infant and lighter infant subgroups) had lower incidence rates of severe asphyxia and smaller head circumference at birth (P<0.05). The mortality rates of both of the twins, the heavier infant of the twins, and the lighter infant of the twins were lower in the 2013-2017 group compared with the 2008-2012 group (P<0.05). Compared with the 2008-2012 group, the 2013-2017 group (both the heavier infant and lighter infant subgroups) had lower incidence rates of pulmonary hemorrhage, patent ductus arteriosus (PDA), periventricular-intraventricular hemorrhage (P-IVH), and neonatal respiratory distress syndrome (NRDS) and a higher incidence rate of bronchopulmonary dysplasia (P<0.05).
CONCLUSIONS
There is a significant increase in the survival rate over time in extremely preterm twins with a gestational age of <28 weeks in the 26 grade A tertiary hospitals in Guangdong Province. The incidences of severe asphyxia, pulmonary hemorrhage, PDA, P-IVH, and NRDS decrease in both the heavier and lighter infants of the twins, but the incidence of bronchopulmonary dysplasia increases. With the improvement of diagnosis and treatment, the multidisciplinary collaboration between different fields of fetal medicine including prenatal diagnosis, obstetrics, and neonatology is needed in the future to jointly develop management strategies for twin pregnancy.
Bronchopulmonary Dysplasia/epidemiology*
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Female
;
Gestational Age
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Humans
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Infant
;
Infant, Extremely Premature
;
Infant, Newborn
;
Pregnancy
;
Respiratory Distress Syndrome, Newborn/epidemiology*
;
Retrospective Studies
;
Treatment Outcome

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