[Establishment and efficiency test of a clinical prediction model of bronchopulmonary dysplasia associated pulmonary hypertension in very premature infants].

Objective: To develop a risk prediction model for identifying bronchopulmonary dysplasia (BPD) associated pulmonary hypertension (PH) in very premature infants. Methods: This was a retrospective cohort study. The clinical data of 626 very premature infants whose gestational age <32 weeks and who suffered from BPD were collected from October 1st, 2015 to December 31st, 2021 of the Seventh Medical Center of the People's Liberation Army General Hospital as a modeling set. The clinical data of 229 very premature infants with BPD of Hunan Children's Hospital from January 1 st, 2020 to December 31st, 2021 were collected as a validation set for external verification. The very premature infants with BPD were divided into PH group and non PH group based on the echocardiogram after 36 weeks' corrected age in the modeling set and validation set, respectively. Univariate analysis was used to compare the basic clinical characteristics between groups, and collinearity exclusion was carried out between variables. The risk factors of BPD associated PH were further screened out by multivariate Logistic regression, and the risk assessment model was established based on these variables. The receiver operating characteristic (ROC) area under curve (AUC) and Hosmer-Lemeshow goodness-of-fit test were used to evaluate the model's discrimination and calibration power, respectively. And the calibration curve was used to evaluate the accuracy of the model and draw the nomogram. The bootstrap repeated sampling method was used for internal verification. Finally, decision curve analysis (DCA) to evaluate the clinical practicability of the model was used. Results: A total of 626 very premature infants with BPD were included for modeling set, including 85 very premature infants in the PH group and 541 very premature infants in the non PH group. A total of 229 very premature infants with BPD were included for validation set, including 24 very premature infants in the PH group and 205 very premature infants in the non PH group. Univariate analysis of the modeling set found that 22 variables, such as artificial conception, fetal distress, gestational age, birth weight, small for gestational age, 1 minute Apgar score ≤7, antenatal corticosteroids, placental abruption, oligohydramnios, multiple pulmonary surfactant, neonatal respiratory distress syndrome (NRDS)>stage Ⅱ, early pulmonary hypertension, moderate-severe BPD, and hemodynamically significant patent ductus arteriosus (hsPDA) all had statistically significant influence between the PH group and the non PH group (all P<0.05). Antenatal corticosteroids, fetal distress, NRDS >stage Ⅱ, hsPDA, pneumonia and days of invasive mechanical ventilation were identified as predictive variables and finally included to establish the Logistic regression model. The AUC of this model was 0.86 (95%CI 0.82-0.90), the cut-off value was 0.17, the sensitivity was 0.77, and the specificity was 0.84. Hosmer-Lemeshow goodness-of-fit test showed that P>0.05. The AUC for external validation was 0.88, and the Hosmer-Lemeshow goodness-of-fit test suggested P>0.05. Conclusions: A high sensitivity and specificity risk prediction model of PBD associated PH in very premature infants was established. This predictive model is useful for early clinical identification of infants at high risk of BPD associated PH.

[Significance of soluble PD-L1 in patients with chronic hepatitis B and hepatitis C].

Objective: The programmed death receptor 1/programmed death ligand 1 (PD-1/PD-L1) pathway can negatively regulate the immune response of the body, and serum soluble PD-L1 (sPD-L1) can reflect the expression level of PD-L1. This study aims to compare the expressional differences of sPD-L1 in serum between patients with chronic hepatitis B (CHB) and C (CHC) and further explore the factors influencing the clinical cure of CHB. Methods: 60 cases with CHB, 40 cases with CHC, and 60 healthy controls were selected. Serum levels of sPD-L1 were detected using an ELISA kit. The relationship between sPD-L1 levels and viral load, liver injury indicators, and others was analyzed in CHB and CHC patients. According to the distribution type of the data, a one-way ANOVA or Kruskal Wallis test as well as Pearson's correlation or Spearman's rank correlation analysis were performed. A difference of P<0.05 was considered statistically significant. Results: The serum sPD-L1 levels were significantly higher in CHB patients (414.6 ± 214.9) pg/ml than those in CHC patients (58.9 ± 122.1) pg/ml and the healthy control group (66.27 ± 24.43) pg/ml, and there was no statistically significant difference in serum sPD-L1 between CHC patients and the healthy control group. Further grouping and correlation analysis showed that the level of serum sPD-L1 was positively correlated with the content of HBsAg in CHB patients but not with HBV DNA, alanine transaminase, albumin, and other liver injury indicators. Additionally, there was no correlation between serum sPD-L1 levels, HCV RNA, and liver injury indicators in CHC patients. Conclusion: The serum sPD-L1 levels are significantly higher in CHB patients than those in the healthy control group and the CHC group, and there is a positive correlation between sPD-L1 levels and HBsAg. The persistent presence of HBsAg is an important mechanism for the activity of the PD-1/PD-L1 pathway, indicating that the activity of the PD-1/PD-L1 pathway may be an important factor that cannot be clinically cured in CHB as in CHC.

[Evaluation of the fresh air purification system in the classroom under heavy pollution weather].

Evaluate the effect of the fresh air purification system on the improvement of indoor PM2.5 levels in a primary school classroom in Jinan City, Shandong Province. Our purpose is to explore the optimal operating time of the fresh air system and the main factors that affect the fresh air purification system to improve indoor air quality. From December 9, 2019 to December 10, 2019, two classrooms of the same area on the third floor of a primary school building in Jinan City, Shandong Province were selected as monitoring points. During the operation of the fresh air purification system, the PM2.5 concentration in the classroom is reduced by an average of 48.1%-61.5% compared to the outdoor PM2.5 concentration. After running for about 2 hours, the indoor PM2.5 concentration decreased to a relatively stable concentration level. The operating time of the fresh air purification system, student activities between classes, indoor temperature, indoor relative humidity, and outdoor PM2.5 concentration are important factors that affect the indoor particulate removal rate. In the case of a certain amount of fresh air and indoor area, closing doors and windows and appropriately extending the operation time of the fresh air purification system can improve the air quality in the classroom to a certain extent and protect the health of students.

[Genotype and phenotype analysis of neonates with neonatal encephalopathy complicated with perinatal hypoxic event].

Objective: To explore the underlying genetic causes of neonatal encephalopathy complicated with perinatal asphyxia. Methods: From the neonates recruited to the Neonatal Genome Project of Children's Hospital of Fudan University between January 2016 and January 2019, 113 neonates with neonatal encephalopathy and acute peripartum or intrapartum event or Apgar score ≤7 were enrolled in this study. The clinical data, laboratory results, the findings of electroencephalograph and magnetic resonance imaging or head ultrasound, and the genetic information were retrospectively analyzed. Results: Of the 133 neonates with neonatal encephalopathy and acute peripartum or intrapartum event or Apgar score ≤7 scores, 77 (57.9%) were males, 56 (42.1%) were female, 56 (42.1%) were delivered via cesarean section, and 77(57.9%) were born by vaginal delivery. Among these cases, 68 (51.1%) were diagnosed of hypoxic ischemic encephalopathy, 25 (18.8%) had intracranial hemorrhage, 20 (15%) were related to genetic diseases, and 5 (3.8%) had sepsis without central nervous infection. A total of 20 cases with positive results by next-generation sequencing test were identified, including 19 cases with pathogenic variations and 1 case with variation of uncertain significance. These 20 cases included 4 cases with congenital myopathy (2 cases of MTM1 gene pathogenic variants, 1 case of ACTA1 and 1 case of RYR1 gene pathogenic variants), 4 cases with genetic syndrome (2 cases of CHD7 gene pathogenic variants, 1 case of PTN11 gene pathogenic variant, and 1 case of NSDHL gene pathogenic variant), 3 cases with metabolic disorders (1 case of OTC gene pathogenic variant, 1 case of MTHFR gene pathogenic variant, and 1 case of ALDH7A1 gene pathogenic variant), 2 cases with epileptic encephalopathy (1 case of KCNT1 and 1 case of PACS2 gene pathogenic variants), 1 case with congenital central hypoventilation syndrome (PHOX2B gene pathogenic variant) and 6 cases with copy-number pathogenic variations. Among these 20 cases, 8(40.0%) neonates were presented with persistent hypotonia, 7(35.0%) neonates with seizures, and 5(25.0%) neonates with congenital malformation. Genetic counseling and further follow-up were performed or suggested for these 20 cases; 4 neonates were deceased, 10 neonates underwent palliative care, and 6 neonates were improved after supportive care and their further follow-up plan were performed in clinics. Conclusions: Genetic diseases are not rare in neonates with neonatal encephalopathy complicated with perinatal hypoxia event. The common causes in these neonates include congenital myopathy, metabolic disorders, genetic syndrome, and epilepsy encephalopathy.

LncRNA MEG3 promotes proliferation and differentiation of osteoblasts through Wnt/ß-catenin signaling pathway.

OBJECTIVE: We aimed at detecting the expression of long non-coding ribonucleic acid (lncRNA) maternally expressed 3 (MEG3) in the serum of fracture patients, and at investigating its impacts on the proliferation and differentiation of osteoblasts and the specific molecular mechanism of action. PATIENTS AND METHODS: The serum samples of 48 fracture patients diagnosed in our hospital (Fracture group) and 30 healthy people receiving physical examination (Health group) were collected. The expression level of serum lncRNA MEG3 in Fracture group and Health group was measured via reverse transcription-polymerase chain reaction (RT-PCR). Furthermore, a small interfering RNA (siRNA) was applied to construct mouse osteoblast cell line MC3T3-E1 with a stable knockout of MEG3. The growth status of the cell was observed, and the impacts of MEG3 knockout on the osteoblast proliferation were determined using cell counting kit-8 (CCK-8), a proliferation activity detection kit. Meanwhile, 5-ethynyl-2'-deoxyuridine (EdU) staining was applied to detect the proportion of EdU positive cells in the osteoblasts in Control group and MEG3 knockout group (MEG3 siRNA group). In addition, RT-PCR was performed to measure the messenger RNA (mRNA) levels of differentiation-related genes. Finally, RT-PCR and Western blotting assay were adopted to analyze the expression of the Wnt/ß-catenin signaling pathway. RESULTS: The expression of serum lncRNA MEG3 in fracture patients was increased markedly (p<0.05). Results of in-vitro cell experiment indicated that intervention with MEG3 siRNA could obviously promote the proliferation and differentiation of osteoblast cell line MC3T3-E1. The results of RT-PCR and Western blotting assay revealed that the role of MEG3 in promoting differentiation and proliferation might be mediated by the activation of the Wnt/ß-catenin signaling pathway in osteoblasts. CONCLUSIONS: LncRNA MEG3 can promote the proliferation and differentiation of osteoblasts by activating the Wnt/ß-catenin signaling pathway, so it is expected to become a new target for accelerating the fracture healing.

[Study on the super-antigen genes of group A Streptococcus pyogenes strains isolated from patients with scarlet fever and pharyngeal infection, in Beijing, 2015-2017].

Objective: To analyze the characteristics of super-antigen (SAg) of group A Streptococcus pyogenes (GAS), isolated from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017. Methods: Throat swab specimens from patients with scarlet fever or pharyngeal infections were collected and tested for GAS. Eleven currently known SAg genes including SpeA, speC, speG, speH, speI, speJ, speK, speL, speM, smeZ and ssa were tested by real-time PCR while M protein genes (emm genes) were amplified and sequenced by PCR. Results: A total of 377 GAS were isolated from 6 801 throat swab specimens, with the positive rate as 5.5%. There were obvious changes noticed among speC, speG, speH and speK in three years. A total of 45 SAg genes profiles were observed, according to the SAgs inclusion. There were significant differences appeared in the frequencies among two of the highest SAg genes profiles between emm1 and emm12 strains (χ(2)=38.196, P<0.001; χ(2)=72.310, P<0.001). There also appeared significant differences in the frequencies of speA, speH, speI and speJ between emm1 and emm12 strains (χ(2)=146.154, P<0.001; χ(2)=52.31, P<0.001; χ(2)=58.43, P<0.001; χ(2)=144.70, P<0.001). Conclusions: Obvious changes were noticed among SAg genes including speC, speG, speH and speK from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017. SAg genes including speA, speH, speI and speJ appeared to be associated with the emm 1 and emm 12 strains. More kinds of SAg genes profiles were isolated form GAS but with no significant differences seen in the main SAg genes profiles, during the epidemic period.

[Analysis of pesticide poisoning in Ji'nan during 2012-2016].

Objective: To study the current situation and distribution characteristics of pesticide poisoning in Ji'nan area, and to provide the basis for formulating the policy of scientific prevention and control of pesticide poisoning. Methods: The cases of pesticide poisoning from 2012 to 2016 were collected from medical institutions in Ji'nan, and the data was subjected to statistical analysis. Results: From 2012 to 2016 in Ji'nan reported a total of 2 237 cases of pesticide poisoning, non productive pesticide poisoning cases (72.78%, 2 149/2 237) and mortality (17.73%, 381/2 149) was significantly higher than that of productive pesticide poisoning. The average age is 46.78±18.57. The highest mortality rate of pesticide poisoning is more than 70 age group of the non productive pesticide poisoning. Organophosphorus pesticides (67.68%, 1 514/2 237) are the main pesticides causing poisoning, followed by herbicide (23.74%, 531/2 237). The highest mortality rate of pesticide was Paraquat (36.45%, 160/439), the second is the dichlorvos (19.19%, 170/886). Conclusion: Pesticide poisoning is a public health problem and social problem which is harmful to the health of the residents in Ji'nan. It is necessary to strengthen the control and management of high toxic pesticides. Pay attention to the psychological intervention of elderly people to reduce the incidence of pesticide poisoning.

[Characteristics on the onset features of scarlet fever in Beijing, 2006-2015].

Objective: This study aimed to explore the incidence trends and onset features of scarlet fever during the years of epidemic, from 2006 to 2015, in Beijing. Methods: Spatial, temporal and population distributions, prognosis of the reported cases and surveillance data on scarlet fever and other streptococcal infections (including the patients of streptococcal infection, tonsillitis and isthmitis) were analyzed by the descriptive epidemiological methods. Results: A total of 27 987 scarlet fever cases were reported from 2006 to 2015, with the incidence rates as 7.04 to 18.53 per 100 000 persons during these years, except for 2011. A total of 6 152 cases were reported in 2011, with the incidence of 31.37 per 100 000 persons, significantly higher than the average levels of the other years. There were more cases reported in rural-urban continuum, in summer and winter, with most of the cases were children in primary schools and infant-institutes. From May to December in 2011, 4 332 cases were interviewed three weeks after the disease onset, and their conditions improved or recovered, with no death or complication appeared at the follow-up period. There were 2 725 cases of scarlet fever and 104 013 clinical cases of streptococcal infections reported in 36 surveillance hospitals during the same period. The ratio between numbers of scarlet fever cases and streptococcal infection was 1 ∶ 38.17. The weekly numbers of scarlet fever were remarkably correlated to the streptococcal infections, with a Pearson's correlation coefficient as 0.729 (P<0.001). Accordingly, we estimated that about 21.4 thousand clinical cases of streptococcal infections that were caused by Group A streptococcus in 2011, in Beijing. Conclusions: Incidence of scarlet fever in 2011 was significantly higher than the average levels of other years in Beijing, but characteristics on spatial, temporal and population distributions of scarlet fever remained the same, with good prognosis of the reported cases. A large number of culture-positive Group A streptococcus infections among all the clinical cases of streptococcal infection might have been served as important source on septic infection, of scarlet fever.

Influences of MxA gene -88 G/T and IFN-gamma +874 A/T on the natural history of hepatitis B virus infection in an endemic area.

The influence of human genetics on the natural history of hepatitis B virus (HBV) infection may be diminished in endemic areas because infection at a young age predisposes to chronic HBV infection. The present study aimed to address this issue through the determination of the influences of single nucleotide polymorphisms (SNPs) of myxovirus resistence-1 (MxA) -88 G/T and interferon (IFN)-gamma +874 A/T on the natural history of HBV infection in endemic regions. One hundred adult patients with self-limiting HBV infection (positive for both anti-HBs and anti-HBc) and 340 adult patients with persistent HBV infection were recruited from southern China, an endemic area with an HBsAg carrier rate of 17.8%. SNPs of MxA -88 G/T and interferon (IFN)-gamma +874 A/T were typed using a protocol based on competitively differentiated polymerase chain reaction. A highly significant difference in the distribution of MxA -88 G/T was observed between those with persistent and self-limiting HBV infections. The latter displayed a lower frequency of the GG genotype (41.0% vs. 52.9%, P = 0.036) and a higher frequency of the TT genotype (16.0% vs. 2.4%, P = 0.000), compared to patients with persistent infection. These differences were not gender- or age-specific. However, a significant distribution difference of IFN-gamma +874 A/T was not observed. Between two groups of patients, respectively, the distribution frequencies of the AA genotype (65.0% vs. 72.8%, P = 0.139) and the TT genotype (2.0% vs. 1.2%, P = 0.894) were found. These results suggest that MxA gene -88 G/T and IFN-gamma +874 A/T behave differently in endemic HBV infections. Further study is necessary to clarify the influences of human genetics on endemic HBV infections.

[Experimental study of restiffening of the rigor mortis].

OBJECTIVE: To observe changes of the length of sarcomere of rat when restiffening. METHODS: We measured the length of sarcomere of quadriceps in 40 rats in different condition by scanning electron microscope. RESULTS: The length of sarcomere of rigor mortis without destroy is obviously shorter than that of restiffening. CONCLUSION: The length of sarcomere is negatively correlative to the intensity of rigor mortis. Measuring the length of sarcomere can determine the intensity of rigor mortis and provide evidence for estimation of time since death.

[Structure elucidation of glycan of a glycoconjugate SPPA-1 isolated from Spirulina platensis].

AIM: To elucidate the structure of the glycan of SPPA-1, a glycoconjugate isolated from Spirulina platensis. METHODS: Methylation analysis, GC/MS, and 1D, 2DNMR techniques were used to determine the structures of the glycoconjugate (SPPA-1). RESULTS: SPPA-1 was only composed of alpha-D-glucose and shown to be a (1-->4) linked alpha-D-glucan to which a few glucosyl side chains are attached at O-6 of the glucosyl residues of the main chain. CONCLUSION: The glycan of SPPA-1 is a new glucan.

[Physico-chemical properties and activity of glycoconjugate LbGp2 from Lycium barbarum L].

AIM: To isolate and purify a glycoconjugate (LbGp2) from the fruit of Lycium barbarum L. and study its immunoactivity and antioxidative activity. METHODS: By means of gel permeation chromatography, LbGp2 was purified. Based on HPLC, CE, GC, SEC and component analysis and so on, its physico-chemical properties were studied. RESULTS: Molecular weights of LbGp2 was 68.2 ku and its carbohydrate content was up to 90.7%. Component analysis showed that it composed of Ara and Gal in a molar ratio of 3:4, and 18 kinds of amino acids. The immunologic function and bioactivity of Lbp2 has been studied preliminarily. Lbp2 was shown to increase rate of phagocyticaction and phagocytic index, promote lymphocyte translation and accelerate the production of serum hemolysin. LbGp2 has distinct effect of antioxidation and the superoxide anion produced by DMSO-NaOH system was scavenged effectively. CONCLUSION: LbGp2 was shown to be a kind of homogeneous glycoconjugate with good immunoactivity and antioxidative activity.

[The SEM observation of brain tissues and vascular corrosion cast of closed diffuse brain injuries].

The morphologic changes of the closed injured brain of rats were observed by SEM. The rats either died immediately after conclusive injuries or were killed after 5 minutes to 5 days after injuries. The main changes were as follows: the diffuse disorder, twist, wave-like distortion and break of neuron fibers; axonal swelling; formation of axonal retraction balls; stripping and denotation of myelin sheath The ball-like swelling of neuron, break of neuron membrane and vascular wall, and microthrombus formations were also observed. These damages worsened with prolongation of surviving time of the rats. The axonal retraction ball appeared 8 hours after the injury and was approximately 3-5 cm in diameter, and developed to 7-8 cm after 3-5 days. It is observed that frontal lobe, cerebellum and brain stem were severely damaged.

[Studies of guben quyu No I combined with chemotherapy in treating cancer].

UNLABELLED: Cancer patients with Qi-Deficiency and Blood Stasis (QDBS) syndrome were studied, and stress was put on the observation of the Guben Quyu No. I, which was used in combining with chemotherapy for synergistic effect and attenuation of toxicity. THE RESULTS: QDBS syndrome often existed in cancer patients, and chemotherapy exacerbate the occurrence rate of QDBS syndrome. QDBS syndrome is somehow related to immuno-deficiency and blood hypercoagulability, the method of Yiqi Huoxue (YQHX) which used to be combined with chemotherapy could not only reduce the toxic-side effects of chemotherapy, but also improve the cellular immune function and hemorheology. Since the cellular immuno-deficiency and blood hypercoagulability were associated with recurrence and metastasis of cancer. It is considered that the Guben Quyu No I possibly is to reduce the occurring of the above-mentioned consequences.