Objective To examin and analyze the structure, ultrastructure and the circulation of the spleen ellipsoid in the soft-shelled turtle, Pelodiseus sinensis. Methods Twelve turtles were used and observed by light- and electron-microscopy and injection of ink suspension in this study. Results The spleen white pulp was consisted of the periarteriolar lymphatic sheath (PALS) and periellipsoidial lymphatic sheath (PELS). There was no lymphoid nodule in the spleen. Red pulp included splenic cords and splenic sinusoids. The marginal zone was not found in the turtle spleen. When the central arteriole left out of the PALS, it divided into several ellipsoid capillaries which were surround by the PELS. The end of the ellipsoid capillary opened directly to the splenic cord and the blood cells then entered into the splenic sinusoid through the gap between the endothelial cells. The ellipsoid capillary was consisted of simple cuboidal epithelium with an uncompleted basement membrane. The ellipsoid wall was consisted of supporting cells,ellipsoid-associated cells and reticular fibres. Lymphocytes and red cells were always found on the ellipsoid wall. After 40min of the injection of ink suspesion, much carbon particles of ink were restricted on the wall. Conclusion The ellipsoid capillary in the soft-shelled turtle, just like the high endothelial venule, was the important passage of the lymphocytes and blood cells going out and into the lymph tissue. The splenic circulation in the turtle belongs to the opening model.

Objective To investigate the correlation between hemoglobin level and health status of the elderly living in communities in Beijing.Methods A random cluster sampling method was used to select residents living in communities of Beijing city,and a cross-sectional study was carried out by questionnaires,scene testing and blood sample collection.WHO-formulated criteria were applied for diagnosing anemia.The health indicators in questionnaires included visual impairment,physical disability,decreased health,self-care,fatigue,anorexia,independent walking distance,exercise frequency,intelligence status and computing power.Results Complete information was obtained in a total of 1 948 elderly people,including 790 cases of male and 1 158 cases of female,with an average age of(73.9±6.1)years and a median age of 74 years(65-100).The mean level of hemoglobin in the 1 948 people was(135.65 ± 14.48) g/L,with (142.56 ± 15.56) g/L in male and (130.95 ± 11.53) g/L in female.Hemoglobin level was significantly lower in female than in men (t =54.739,P＜ 0.01).Hemoglobin level was decreased with aging,and negatively associated with appetite,physical strength,walk assistance,visual acuity and physical ability(r=-0.055,-0.067,-0.071,-0.114,-0.095;P =0.022,0.005,0.004,0.000,0.000),while positively associated with health status,activities in daily life,athletic ability,exercise frequency and intelligence (r =0.073,0.126,0.122,0.066,0.124;P =0.002,0.000,0.000,0.006,0.000).Conclusions The hemoglobin level of the elderly decreases with aging and is associated with health status and quality of life in the elderly,which should be taken care seriously.

Objective:To investigate the significance of N-terminal pro-brain natriuretic peptide (NT-proBNP) in the early assessment of neonatal cardiac dysfunction in sepsis.Methods:The children diagnosed with neonatal sepsis and common infection neonates admitted to the department of pediatric neonatal intensive care unit (NICU) of Liaocheng People's Hospital from January 2016 to January 2019 were enrolled. Data of clinical sign, laboratory results, bedside echocardiography and survival data were collected, and the differences of clinical indexes were compared among sepsis patients with and without cardiac dysfunction and common infection. The risk factors of sepsis with cardiac dysfunction were analyzed by multivariate Logistic regression, and the early prediction value of NT-proBNP for neonatal septic cardiac dysfunction was evaluated by the receiver operating characteristic (ROC) curve.Results:There were 112 neonates with sepsis (49 with cardiac dysfunction and 63 without cardiac dysfunction) and 67 children with common infection included in the analysis. The onset time of neonates in septic cardiac dysfunction group was significantly earlier than that of septic non-cardiac dysfunction group and common infection group [hours: 52.9 (0, 180.3) vs. 53.9 (0, 183.6), 81.0 (45.6, 202.4), both P < 0.05]. Compared with the general infection group, albumin (ALB), white blood cell count (WBC), left ventricular ejection fraction (LVEF) in septic cardiac dysfunction group significantly decreased, NT-proBNP, hypersensitive C-reactive protein (hs-CRP)/ALB, pulmonary artery systolic pressure (PASP) significantly increased, while right ventricular (RV) and Tei index significantly increased [ALB (g/L): 24.1±3.8 vs. 27.8±3.6, WBC (×10 9/L): 12.7 (3.7, 18.9) vs. 15.4 (9.9, 23.2), LVEF: 0.626±0.123 vs. 0.700±0.021, NT-proBNP (ng/L): 20 230.6 (15 890.0, 35 000.0) vs. 7 324.5 (2 426.5, 13 890.0), hs-CRP/ALB: 0.33 (0.29, 0.81) vs. 0.06 (0.00, 0.21), PASP (mmHg, 1 mmHg = 0.133 kPa): 52.25±14.12 vs. 41.07±27.73, RV (mm): 10.74±2.42 vs. 8.55±1.41, Tei index: 0.52±0.03 vs. 0.30±0.04, all P < 0.05]. NT-proBNP and Tei index in septic cardiac dysfunction group were significantly higher than those in septic non-cardiac dysfunction group [NT-proBNP (ng/L): 20 230.6 (15 890.0, 35 000.0) vs. 13 057.6 (8 946.0, 35 000.0), Tei index: 0.52±0.03 vs. 0.39±0.02, both P < 0.05], and LVEF was significantly lower than that in septic non-cardiac dysfunction group (0.626±0.123 vs. 0.671±0.086, P < 0.05). Multivariate Logistic regression analysis showed that NT-proBNP, Tei index and hs-CRP/ALB were independent risk factors for cardiac dysfunction in sepsis neonates [odds ratio ( OR) and 95% confidence interval (95% CI) were 8.73 (1.54-5.67), 1.97 (1.26-2.87), 1.87 (1.03-3.40) respectively, all P < 0.05]. ROC curve analysis showed that NT-proBNP, Tei index and hs-CRP/ALB had good predictive value for the occurrence of cardiac dysfunction in septic neonates, the area under ROC curve (AUC) was 0.81 (95% CI was 0.84-0.91), 0.78 (95% CI was 0.65-0.79) and 0.77 (95% CI was 0.61-0.77), respectively. The sensitivity and specificity of NT-proBNP were 80.0% and 79.0% respectively with 12 291.5 ng/L as the cut-off value, the sensitivity and specificity of Tei index were 74.0% and 77.0% respectively with 0.45 as the cut-off value, and the sensitivity and specificity of hs-CRP/ALB were 76.0% and 76.3% respectively with 0.10 as the cut-off value. Conclusions:NT-proBNP can be used as a diagnostic marker of early cardiac dysfunction, and for rapid diagnosis of neonatal cardiac dysfunction in sepsis. The application may guide clinicians to use drugs better to improve cardiac function and treatment effect.

Objective:To investigate the status and influencing factors of enteral nutrition support in late preterm infants (34-36 +6 gestational weeks) treated in different grades of hospitals in Beijing. Methods:This was a prospective study involving late preterm infants treated in 25 hospitals in Beijing from October 2015 to October 2017. Data about nutritional management and nutrition-related complications were recorded. Exclusive breastfeeding status of the infants by gestational age(GA) and hospital levels was analyzed. The achievement of full enteral feeding and the potential influencing factors were also analyzed. t-test, Mann-Whitney U test, analysis of variance (ANOVA), Kruskal-Wallis test and Chi-square test were used for statistical analysis. Logistic regression and Cox regression analysis were used in multivariate analysis. Results:(1) A total of 1 463 late preterm infants with GA of 35.6±0.8 (ranging from 34.9 to 36.1) weeks was enrolled in this study. Compared with the infants with GA of 35-35 +6 and 36-36 +6 weeks, those born at 34-34 +6 gestational weeks had longer hospital stay [10 (8-13) vs 8 (7-10) and 7 (6-9) d, both P<0.05], greater loss of minimum weight [4.3% (2.6%-6.3%) vs 3.8% (2.0%-5.6%) and 3.3% (1.9%-5.5%), both P<0.05], higher incidence of apnea [5.3% (20/369) vs 2.1% (12/566) and 1.3% (7/528), both P<0.05] and respiratory distress syndrome (RDS) [7.1% (28/369) vs 3.0% (17/566) and 3.2% (17/528), both P<0.05], and lower percentage of failure to regain birth weight at discharge [32.5% (120/369) vs 38.7% (219/566) and 47.9% (253/528), both P<0.05]. Only the incidence of premature rupture of membranes among all maternal complications during pregnancy had statistical difference between 34-34 +6, 35-35 +6 and 36-36 +6 GA groups [6.2% (23/369) vs 12.7% (72/566) and 11.9% (63/528), χ2=10.244, P=0.007]. (2) The rate of enteral feeding increment in hospital was 13.7 (10.5-17.3) ml/(kg·d) and 46.0% (673/1 463) of the infants were fed formula. The exclusive breastfeeding rate increased from 4.5% (66/1 463) during hospitalization to 14.4% (211/1 463) at discharge. The breastfeeding rate at discharge varied widely among the 25 hospitals ( χ2=327.893, P<0.001) ranging from 32% to 0. (3) Logistic regression analysis demonstrated that gestational diabetes mellitus ( OR=2.426, 95% CI: 1.075-5.437, P=0.033) and premature rupture of membranes ( OR=8.726, 95% CI: 1.193-63.802, P=0.033) were the prenatal risk factors influencing the exclusive breastfeeding in late preterm infants. Enteral nutrition achieving 150 ml/(kg·d) and 120 kcal/(kg·d) (1 kcal=4.184 kJ) were noted for 28.4% (416/1 463) and 19.2% (281/1 463) of the late preterm infants at discharge, respectively. Cox regression analysis showed that hospital grades ( HR=1.470, 95% CI: 1.030-2.098, P=0.034), the length of hospital stay ( HR=1.162, 95% CI: 1.097-1.231, P<0.001), birth weight ( HR=0.946, 95% CI: 0.898-0.995, P=0.003), exclusive breastfeeding ( HR=2.354, 95% CI:1.031-5.374, P=0.042), feeding intolerance ( HR=3.677, 95% CI: 1.201-11.253, P=0.023), parenteral nutrition ( HR=1.900, 95% CI: 1.379-2.616, P<0.001), and the rate of enteral feeding advancement ( HR=1.426, 95% CI: 1.369-1.484, P<0.001) were independent factors associated with full enteral feeding at discharge. Conclusions:Exclusive breastfeeding rate in late preterm infants is low and enteral nutrition support varies greatly in different hospitals. The rate of enteral feeding increment is slow for hospitalized late preterm infants and most fail to achieve full enteral feeding at discharge. Gestational diabetes mellitus and premature rupture of membranes are prenatal risk factors affecting breastfeeding of late preterm infants. Those with low birth weight, exclusive breastfeeding in hospital, feeding intolerance, parenteral nutrition support, longer hospital stay or rapid enteral feeding advancement are more likely to achieve full enteral feeding at discharge.

Objective:To investigate the value of N-terminal pro-brain natriuretic peptide (NT-proBNP) combined with bedside echocardiography in diagnosis and treatment of neonatal sepsis with cardiac dysfunction.Methods:A total of 56 children diagnosed with neonatal sepsis in the Neonatal Intensive Care Unit, Liaocheng People′s Hospital from July 2016 to July 2017 were enrolled and divided into 2 groups, namely, the cardiac dysfunction group (26 cases) and the non-cardiac dysfunction group (30 cases). Children with general infection (45 cases) hospita-lized at the same period were taken as the control group.The clinical characteristics, related laboratory indexes and prognosis were compared among 3 groups.The related factors of neonatal sepsis with cardiac dysfunction were analyzed by the multivariate Logistic regression approach, and the value of related indexes in the early prediction neonatal sepsis with cardiac dysfunction was analyzed by using the receiver operating characteristic curve (ROC). Results:The onset age of sepsis patients with cardiac dysfunction [63.0 h (30.5 h, 185.6 h)] was significantly earlier than that of the patients without cardiac dysfunction [65.0 h (34.5 h, 170.6 h)] and the control group [80.0 h (45.5 h, 202.3 h)] ( P<0.05). The main primary site of the disease was the lung, which was not statistically significant among the 3 groups ( P>0.05). The NT-proBNP level and the high sensitivity-C-reactive protein (hs-CRP)/albumin (ALB) ratio in the cardiac dysfunction group [20 230.6 ng/L (15 890.0 ng/L, 35 000.0 ng/L); 0.33(0.29, 0.81)] were significantly higher than those in the control group [7 324.5 ng/L (2 426.5ng/L, 13 890.0 ng/L); 0.06(0, 0.21)] (all P<0.05). The right ventricular diameter and the Tei index of the cardiac dysfunction group [(8.74±2.42) mm; 0.52±0.03] were significantly higher than those in the control group [(8.55±1.41)mm; 0.30±0.04], while the EF of the cardiac dysfunction group [(62.61±2.56)%] was significantly lower than that in the control group [(70.03±0.35)%] (all P<0.05). The ROC curve analysis showed that NT-proBNP and the Tei index could effectively predict sepsis with cardiac dysfunction.Specifically, NT-proBNP had a cutoff value of 12 291.5 ng/L, with sensitivity of 80%, specificity of 79%, and the area under ROC curve (AUC) of 0.81.The Tei index had a cutoff value of 0.45, with sensitivity of 74%, specificity of 77%, and the AUC of 0.78. Conclusions:NT-proBNP can be used as a marker of early cardiac dysfunction.Its combination with the Tei index of bedside echocardiography can quickly diagnose cardiac dysfunction of children with sepsis, better guide clinicians in drug use, improve cardiac function of patients and enhance the treatment effect.

Objective:To analyze the prevalence of anemia and its influencing factors in the elderly population dwelling in urban communities in Beijing.Methods:A random cluster sampling method was adopted to select the elderly people of communities in Beijing, and cross-sectional research was conducted through questionnaire surveys, field tests and blood sample collection.The criteria for diagnosing anemia were from WHO standards, and the health evaluation indicators in the questionnaire survey included demographic data and eating habits, socio-economic information, information on enjoying health services, health and physical fitness and other information.Blood samples were drawn for routine blood tests and biochemical tests.Results:A total of 1 947 elderly people aged 65 years and above were investigated, including 789 males(40.5%)and 1 158 females(59.5%). Among the 1 947 survey subjects, 288 elderly people had anemia, with the prevalence of anemia of 14.79%(288/1 947). The prevalence of anemia was 16.35%(129/789)in males and 13.73%(159/1 158)in females.There was no statistically significant difference in the prevalence of anemia between male and female( χ2=2.760, P=0.097). Logistic regression analysis was used to analyze the factors affecting anemia.The results showed that the higher age( OR=1.055, P=0.000), the higher frequency of meat-eating( OR=1.353, P=0.046), the lower frequency of fruit-eating( OR=0.759, P=0.048), the worse health status of cohabitants( OR=0.757, P=0.037), the lower BMI( OR=0.905, P=0.001)and the lower exercise frequency( OR=0.769, P=0.012)were correlated to the higher anemia risk in the elderly population dwelling in urban communities in Beijing. Conclusions:The prevalence of anemia is relatively high in the elderly in Beijing communities.According to our findings, older people should reduce the frequency of eating meat, while ensuring nutritional intake, increase the intake of fruits and take appropriate exercises to reduce the prevalence of anemia.

Objective:To investigate the current nutrition support status of hospitalized small for gestational age infants born late preterm in hospitals of Beijing, and analyze the influencing factors.Methods:Clinical data of late preterm infants from 25 medical units in Beijing between October 2015 and October 2017 was collected and analyzed. Infants were assigned into two groups according to the relationship between their gestational age and birth body weight as small for gestational age(SGA) group and not small for gestational age(non-SGA) group, to compare their nutritional status and explore the related influential factors.Results:Totally, 1 347 late preterm infants were enrolled, including 730 males and 617 females, 151 in SGA group and 1 196 in non-SGA group. The data showed that the rate of exclusive breast-feeding was higher (5.3% vs 4.5%, P<0.01), and the increasing of milk volume was slower [11.0 vs 12.1 ml/(kg·d), P=0.003] in SGA group. More parenteral nutrition was used (77.5% vs 53.1%, P<0.01), and the duration of parenteral nutrition was longer (5.0 vs 2.0 days, P<0.01) in SGA group. The birth weight(1 940 vs 2 490 g, P<0.01), the lowest body weight(1 890 vs 2 400 g, P<0.01) and the discharged body weight(2 135 vs 2 530 g, P<0.01)were lower in SGA group. The SGA group showed lower body weight loss(3.1% vs 8.0%, P=0.015), slower weight growth(13.3 vs 33.0 g/d, P<0.01), and longer length of hospital stay (11.0 vs 8.0 days, P<0.01). In SGA group, the milk volume at discharge [145.6 vs 122.2 ml/(kg·d), P<0.01] and the caloric of enteral feeding at discharge [443.9 vs 384.1 kJ/(kg·d), P<0.01] were higher, the rate of infants who regained their birth weight during hospitalization(78.8% vs 57.9%, P<0.01) was higher, and the rate of ones who achieve full enteral feeding (31.8% vs 16.6%, P<0.01) was higher. A Cox regression analysis in which we set infants can achieve full enteral feeding as goal showed that independent factors associated with full enteral feeding at discharge in SGA group included the increasing of enteral feeding, the duration of parenteral nutrition, whether the length of hospital stay longer than 7 days or not whether exclusive breastfeeding and whether the mothers of enrolled infants were diagnosed gestational diabetes mellitus or placental abruption during pregnancy ( P<0.05). Conclusions:Infants in SGA group show slower increasing of milk volume and lower caloric amount of enteral feeding. More parenteral nutrition is used, and the duration of parenteral nutrition is longer in SGA group. Due to the longer length of hospital stay in SGA group, the milk volume and the caloric of enteral feeding at discharge are higher, more infants regain their birth weight during hospitalization, and more infants achieve full enteral feeding at discharge. Despite of higher portion of parenteral nutrition, infants in SGA group show slower weight growth and lower body weight at discharge.

This study was performed to explore the impact of glutamine(Gln)on the anti-tumor immune response of CD8+ T cells and its mechanism.TCGA database was used to analysis the relationship between tumor Gln metabolism and the quantity and functionality of infiltrating CD8+ T cells.CRISPR/Cas9 was employed to knock down GLS expression in mouse MC38 cells,and a mouse tumor model was established.Flow cytometry was conducted to assess tumor proliferation,apoptosis,and the quantity and functionality of tumor-infiltrating immune cells.Lymphocytes isolated from health individuals were treated with Gln-deficient media,complete media or media supplemented with GSH,RSL3 in vitro.Then the apoptosis,the expression levels of GPX4,Lipid-ROS,and effector function protein of CD8+ T cells were detected by flow cytometry.Furthermore,RNA-seq was performed to analyze the differential gene expression on the Gln-depleted CD8+ T cells.Data showed that tumor Gln metabolism was inversely associated with the quantity and functionality of tumor-infiltrating CD8+ T cells.Low expression of GLS in MC38 cells could inhibit C57BL/6 tumor growth,decrease Ki-67 expression,promote casepase-3 expression,increase the amount of tumor-infiltrating immune cells,suppress PD-1,TIM-3,and LAG-3 expression,and enhance CD137,CD107a,IFN-γ and TNF-α expression in tumor-infiltrating CD8+ T cells.RNA-seq results indicated an upregulation of ferroptosis genes TFRC,HMOX1,CYBB and SLC7A11 in CD8+ T cells following glutamine deficiency.Gln deficiency led to lower CD137,CD107a,IFN-γ,GSH,GPX4 expression,increased Lipid-ROS level,and caused cell death in CD8+ T cells.Supplementation of GSH upregulated GPX4 expression,downregulated Lipid-ROS level,and increased IFN-γ secretion in CD8+ T cells.In conclusion,Gln deficiency inhibits the effector function of CD8+ T cells by inducing ferroptosis,and promotes tumor growth.

OBJECTIVETo identify the epidemiology and etiology characteristics of Tibetan sheep plague in Qinghai plateau.

METHODSThe background materials of Qinghai Tibetan sheep plague found during 1975 to 2009 were summarized, the regional, time and interpersonal distribution, infection routes, ecological factors for the spread were used to analyze; followed by choosing 14 Yersinia pestis strains isolated from such sheep for biochemical test, toxicity test, virulence factors identification, plasmid analysis, and DFR genotype.

RESULTSFrom 1975 to 2009, 14 Yersinia pestis strains were isolated from Tibetan sheep in Qinghai province. Tibetan sheep, as the infection source, had caused 10 cases of human plague, 25 plague patients, and 13 cases of death. All of the initial cases were infected due to eating Tibetan sheep died of plague; followed by cases due to contact of plague patients, while all the initial cases were bubonic plague. Cases of bubonic plague developed into secondary pneumonic plague and septicemia plague were most popular and with high mortality. Most of the Tibetan sheep plague and human plague occurred in Gannan ecological zone in southern Gansu province, which was closely related to its unique ecological and geographical landscape. Tibetan sheep plague coincided with human plague caused by Tibetan sheep, especially noteworthy was that November (a time for marmots to start their dormancy) witnesses the number of Yersinia pestis strains isolated from Tibetan sheep and human plague cases caused by Tibetan sheep. This constituted the underlying cause that the epidemic time of Tibetan sheep plague lags obviously behind that of the Marmot plague. It was confirmed in the study that all the 14 strains were of Qinghai-Tibet Plateau ecotype, with virulence factors evaluation and toxicity test demonstrating strains as velogenic. As found in the (Different Region) DFR genotyping, the strains isolated from Yushu county and Zhiduo county were genomovar 5, the two strain isolated from Nangqian county were genomovar 5 and genomovar 7, while those isolated Delingha region were genomovar 8.

CONCLUSIONTibetan sheep were vulnerable to plague infection, hence causing human plague as the infectious source. The Yersinia pestis strains isolated from Tibetan sheep plague carried pathogen characteristics of Qinghai-Tibet plateau plague, developing many new characteristics of such plague.

Animals ; Ecology ; Genotype ; Geography ; Humans ; Marmota ; Plague ; epidemiology ; veterinary ; Plasmids ; Sheep ; microbiology ; Tibet ; epidemiology ; Yersinia pestis

Objective: To investigate the effect of hypertensive disorder complicating pregnancy (HDCP) on the mortality and early complications of premature infants. Methods: The general clinical data of preterm infants with gestational age 24-36^{+ 6} weeks were collected from the cooperative units in the task group from January 1, 2013 to December 31, 2014.According to the severity of HDCP, the infants were divided into 4 groups: HDCP group, preeclampsia group, eclampsia group and non HDCP group, the mortality and major complications of preterm infants were compared, and the influencing factors were analyzed. Results: The mortality rate of preterm in the HDCP group was significantly higher than that of non HDCP group, and there was statistical significance (χ²=9.970, P=0.019). Eclampsia had a highest fatality rate (4.8%) in the early stage, compared with non HDCP group (2.2%), and the difference was statistically significant.Comparison of HDCP group (1.8%) and eclampsia group (3.2%) suggested that there was no statistically significant difference.The incidence of respiratory distress syndrome (RDS) in preterm in HDCP group was significantly higher than that of non HDCP group, and there was statistical significance (χ²=13.241, P=0.004). Eclampsia group showed the highest incidence (35.4%), compared with non HDCP group (16.2%), the difference was statistically significant, but compared with HDCP group (19.9%), preeclampsia group (17.1%), there was no significant diffe-rence.The incidence of bronchopulmonary dysplasia (BPD) in preterm in HDCP group was significantly higher than that of non HDCP group (χ²=9.592, P=0.022), the highest incidence showed up in eclampsia group (9.7%), compared with non HDCP group (2.0%) and HDCP group (1.7%), the difference was statistically significant.But there was no statistically significant difference, compared with preeclampsia group.As the degree of HDCP aggravated, the incidence of BPD gradually rose.There was no significant impact on necrotizing enterocolitis (NEC), retinopathy of prematurity (ROP), intraventricular hemorrhage (IVH) and sepsis of HDCP (χ²=7.054, 7.214, 0.358, 3.852; P=0.070, 0.065, 0.949, 0.278). Considering the overall outcome of the child, that was, whether the child died or survived, he had at least one complication, and HDCP had an effect on it (χ²=15.697, P=0.001), so the incidence increased while the degree of HDCP rose gradually.After adjusting gestational age, birth weight, sex, way of delivery, placental abruption and front placenta, prenatal hormonal, gestational diabetes, neonatal asphyxia and other factors, the results displayed that HDCP was the factor leading to the death of premature baby (OR=2.159, 95%CI: 1.093-4.266), and comparison between preeclampsia and eclampsia showed no statistical difference (P=0.714, 0.389); HDCP had no significant influence on RDS, BDP, ICH, NEC, ROP and sepsis. Conclusions HDCP leads to increased risk of premature death, but also leads to the increased incidence of RDS and BPD, but it had no obvious effect on NEC, ROP, IVH, sepsis and other complications.