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Background/Aims: Nasal continuous positive airway pressure (nCPAP) was recommended as the initial respiratory support for spontaneous breathing in infants with very low birth weight and neonatal respiratory distress syndrome (NRDS). Less invasive surfactant administration (LISA) and minimally invasive surfactant therapy (MIST) have been reported to reduce the incidence of bronchopulmonary dysplasia (BPD). This study aimed to explore the applicability of minimally invasive surfactant administration (MISA) in China. Materials and Methods: MISA was a randomized controlled study conducted at eight level III neonatal intensive care units (NICUs) in China. Spontaneously breathing infants born at 25+0 to 31+6 weeks' gestation who progressively developed respiratory distress during the first 6 h after birth were randomly assigned to receive MISA or endotracheal intubation surfactant administration (EISA). The primary outcome was the difference in the morbidity of BPD between two groups of infants with MISA and EISA at 36 weeks corrected gestational age. Results: Demographic and clinical characteristics of the 151 infants in the MISA group were similar to the 147 infants in the EISA group. The comparison showed no clear benefits in the MISA group in the incidence of BPD, while infants from the EISA group had higher rates of patent ductus arteriosus (PDA) (60.5 vs. 41.1%, p = 0.001). The duration of surfactant infusion and the total time of surfactant administration in the MISA group were significantly longer than in the EISA group. A slightly increased heart rate was noted 1 h post surfactant administration in the EISA group. In subgroup analysis, the comparison of 51 smaller (

OBJECTIVE: To identify risk factors for minimally invasive surfactant administration (MISA) failure in the treatment of preterm infants with respiratory distress syndrome (RDS) and the influence of MISA failure on neonatal outcome. METHODS: A retrospective analysis was performed for the clinical data of 148 preterm infants with a gestational age of ≤ 32 weeks and a clinical diagnosis of RDS, who were admitted to the neonatal intensive care unit of eight tertiary hospitals in Beijing, Tianjin and Hebei Province from July 1, 2017 to December 31, 2018 and were treated with MISA (bovine pulmonary surfactant, PS). According to whether MISA failure (defined as the need for mechanical ventilation within 72 hours after MISA) was observed, the infants were divided into two groups:MISA failure group (n=16) and MISA success (n=132). A logistic regression analysis was used to investigate the risk factors for MISA failure and its influence on neonatal outcome. RESULTS: The MISA failure rate was 10.8% (16/148). The logistic regression analysis showed that a high incidence rate of grade > Ⅱ RDS before PS administration, low mean arterial pressure and high pulse pressure before administration, a low dose of initial PS administration, and long injection time and operation time were the risk factors for MISA failure (OR=5.983, 1.210, 1.183, 1.055, 1.036, and 1.058 respectively, P < 0.05). After the control for the above risk factors, the logistic regression analysis showed that the MISA failure group had a significantly higher incidence rate of bronchopulmonary dysplasia (BPD) (OR=8.537, P < 0.05). CONCLUSIONS: A high grade of RDS, a low mean arterial pressure, and a high pulse pressure before administration are independent risk factors for MISA failure, and a low dose of initial PS administration, a long injection time, and a long operation time may increase the risk of MISA failure. MISA failure may increase the incidence rate of BPD in preterm infants.

The scarcity of hematopoietic stem cells (HSCs) significantly hindered their clinical potentials. Umbilical cord blood (UCB) has become the leading source of HSCs for both research and clinical applications. But the low content of HSCs in a single UCB unit limited its use only to pediatric patients. Various cytokines and small molecules have demonstrated strong abilities in promoting HSC ex vivo expansion, of which UM171 is the newest and by far the most potent HSC ex vivo expansion agent. In this study, we synthesized 37 pyrimidoindole analogs and identified 6 compounds to be potent in promoting HSC ex vivo expansion. In particular, analog 11 was found to be the most effective in stimulating ex vivo expansion of UCB CD34+ cells and CD34+CD38− cells. Initial data indicated that compound 11 promoted the absolute number of long term HSCs and inhibited their differentiation. UCB HSCs expanded with 11 retained adequate multi-lineage differentiation capacity. In addition, compound 11 is not cytotoxic at its test concentrations, suggesting that it merits further investigation for potential clinical applications.

Background: Preeclampsia (PE) is relatively common and is unpredictable in its onset and progression. Aims: We investigated the clinical value of using the multiple of the median (MoM) of free β-human chorionic gonadotropin (β-hCG) concentrations in women with normal pregnancy and PE. Methods: This study was based on a dataset available from published studies, and the relevant studies were retrieved from multiple electronic databases. Data were extracted from case-control studies; a random-effects model was employed, and standardized mean difference and 95% confidence intervals were calculated. Twelve case-control studies (eleven English-based articles and one Chinese-based article) were analyzed in the current meta-analysis and included 702 patients with PE and 8,233 women with normal pregnancies. Results: Statistical analysis revealed a higher MoM of β-hCG serum levels in patients with PE. Ethnicity subgroup analysis showed that the MoM of serum β-hCG levels was significantly higher in women with PE in both Asian and Caucasian populations. Conclusion: The MoM of β-hCG serum levels was significantly increased in women with PE compared to women with normal pregnancies. Screening for serum β-hCG MoM levels will be helpful in the early identification of pregnancies at risk of developing PE.

Conduction heating overcomes the shortage of the furnace, due to rapid heating and high energy efficiency. The heating experiment of ultra-high strength boron steel (LG1500HS) of a rectangular blank was implemented on the conduction heating system. The variations of the average temperature rising rate, uniform temperature region and energy efficiency were investigated under the non-heating-retaining condition. The results show that the average temperature rising rate, uniform temperature region and energy efficiency are 44.5°C/s, 225 mm and 71.6%, respectively.

The Henry reaction of aromatic aldehydes and nitroalkanes could be performed by catalyst of Lipase A from Aspergillus niger in organic/water medium, and the corresponding Henry products were obtained in yields up to 94%.

The hot forming parts of high strength steel are difficult to cut with the presses and the traditional high-energy beam due to its high tensile strength which can be up to 1500Mpa and its complex structure. And the 3D laser cutting is an effective way to solve the problem. However some problems in the laser process affect the efficiency and quality seriously, including interference between the robot arms and the cutting head with the untrimmed parts, difficulty in determining the entry point and over burning etc. In this research three measures are taken to cut the anti-collision beam, including using photogrammetric technology to get its uncutted 3D model for offline programming to avoid interference, selecting appropriate entry point to trim without interrupt, amending normals and adjusting the process parameters at corners to prevent over burning. The results show that the efficiency and quality are improved and a creative new offline programming method is put forward.

The development of new products of seamless tubes require the development of corresponding grooves in order to manufacture tubes with high precision, high efficiency at low cost. In this work, a finite element model and dynamic simulation of continuous rolling pass for seamless tubes process has been implemented under the ANSYS/LS-DYNA environment to verify the validity of the pass design. The result show the deformation characteristic of cross-section, the variation regularity of rolling force, strain and stress conform to the reality. The work is effective for developing new grooves and products for seamless tube continuous rolling.

Tungsten disulfide nanotubes were fabricated by means of decomposition of ammonium tetrathiotungstate ((NH4)2WS4) on anodized aluminum oxide (AAO) template. The morphology and structures of WS2 nanotubes were characterized by transmission electron microscopy (TEM), electron diffraction. The nanopores in template, the incorporation method and soakage time have function on the structure of WS2 nanotubes.

Different grain size of starting powder was choosed and different sintering additives were used to fabricate Si3N4 ceramics by pressureless sintering. Samples’ relative density and mechanical properties including Vickers hardness, bending strength and fracture toughness were tested. Then XRD, SEM and EDS were carried out to identify phase and observe microstructure and fracture morphology. The result shows that high purity α phase Si3N4 powder of 5 μm is suitable for sintering and combination of 5 wt.% MgO +5 wt.% Y2O3 is most effective within six kinds of sintering aids.

Base on the structure and working principle of electronic fuel injector, according to the related theories of electromagnetic field and flow field, the mathematical model of the electromagnetic force and fuel pressure have been deduced. Then using the finite element method to make a detailed analysis of magnetic permeability, core diameter, the working air gap, winding radius influence on the dynamic characteristic of the injector. According to this analysis, optimize those parameters for a new electronic injector, using the dynamic measurement system for a test, the results show the optimized injector has a better dynamic response than the unoptimized one.

Al-NaI radioactive transmutation target was prepared by powder metallurgy. The existing way of the phase of target was analyzed by the application of XRD and its microstructure and morphology was observed by SEM. Then EDS was used for micro-area energy spectrum analysis and the property of target with different NaI was measured and compared. The results show that NaI is uniformly distributed within the aluminum matrix. The relative density and bending strength of transmutation targets decrease with the increasing content of NaI. The hardness and electrical resistivity of transmutation targets increase with the increasing content of NaI.

To explore the the correlations of p16INK4A (p16) and survivin expressions with cervical intraepithelial neoplasia (CIN) and cervical squamous cell carcinoma.The p16 and survivin expressions were detected in 50 cervical squamous cell carcinoma tissues, 150 various grades of CIN tissues and 30 normal cervical tissues using immunohistochemistry. All data were analyzed applying SPSS 17.0 software.The p16 and survivin expressions showed the presence of statistical significance in cervical cancer, CINI, CINII, CINIII and normal cervical tissues (P0.05), and the comparison also revealed statistical significance among groups (all P0.05); the p16 and survivin expressions were positively correlated with the grade of cervical diseases (both P0.05). Moreover, p16 protein was associated with CIN grade and lymph node metastases in cervical cancer (all P0.05); survivin protein was also related with clinical stages, CIN grade and lymph node metastases (all P0.05); the p16 and survivin expressions were positively correlated with cervical cancer (r=0.854, P0.001), and associated with poor prognosis of cervical cancer.Briefly, p16 and survivin expression may be correlated with the clinico-pathological and prognosis of cervical cancer.

Computed tomography combined with angiography has recently been developed to visualize three-dimensional (3D) vascular structure in experimental and clinical studies. However, there remain difficulties in using conventional x-ray angiography to detect small vessels with a diameter less than 200 μm. This study attempted to develop a novel method for visualizing the micro-angioarchitecture of rat spinal cord. Herein, synchrotron radiationbased x-ray in-line phase contrast computed tomography (IL-XPCT) was used to obtain 3D micro-vessel structure without angiography. The digital phase contrast images were compared with conventional histological sections. Our results clearly demonstrated that the resolution limit of the spatial blood supply network in the normal rat thoracic cord appeared to be as small as ∼10 μm. The rendered images were consistent with that obtained from histomorphology sections. In summary, IL-XPCT is a potential tool to investigate the 3D neurovascular morphology of the rat spinal cord without the use of contrast agents, and it could help to evaluate the validity of the pro- or anti-angiogenesis therapeutic strategies on microvasculature repair or regeneration. (Some figures may appear in colour only in the online journal)

Aims To investigate whether metformin regulates chemerin expression in vivo by alleviating ER stress. Methods Male Sprague-Dawley rats were fed a high-fat or normal diet for 10 weeks to induce insulin resistance. During the following 6 weeks, the rats were divided into four groups: normal diet without treatment (NC), normal diet with metformin treatment (NM), high-fat diet without metformin (HF), and high-fat diet with metformin (HM). Body weight, fasting glucose, basal insulin level, insulin sensitivity, chemerin expression in serum and adipose tissue, ER stress marker and its pathway were measured. Results After 6 weeks treatment, metformin reduced the body weight gain and enhanced insulin sensitivity of high-fat fed rats. The basal insulin level in the HM group was lower than in the HF group. Metformin reduced chemerin expression in the HM group compared with HF. Metformin reduced the GRP78 mRNA expression in HM rats. Activation of IRE1 alpha was lower in the HM group than the HF group. Conclusions Metformin treatment decreased the chemerin expression and alleviated the ER stress in the visceral adipose tissue of high-fat diet-induced insulin-resistant rats. These data may also provide a further rationale for exploring the use of metformin in the treatment of insulin resistance.