Objective To compare the characteristics of respiratory distress syndrome(RDS) between early preterm infants and late preterm(LP) infants,and to investigate the high-risk factors and clinical characteristics of RDS in LP infants.Methods A total of 240 premature infants with RDS treated in our hospital from January 2014 to January 2015 were selected and divided into 2 groups according to the gestational age(GA),143 cases in early preterm group (GA <34 weeks) and 97 cases in LP group(GA 34-36 weeks).The basic situation,high risk factors in perinatal period,clinical characteristics,treatment and prognosis in RDS premature infants were retrospectively analyzed.Results The delivery mode in the LP group was mainly dominated by cesarean section,the cesarean section rate reached 83.51%,which was significantly higher than that in the early preterm group (P<0.05).The premature occurrence rate caused by cesarean section because of premonitory uterine rupture was higher (27.84%);the treatment effect of pulmonary surfactant(PS) and noninvasive assisted ventilation therapy in the LP group was inferior to that in the early premature group,moreover the mechanical ventilation rate was higher,the duration of mechanical ventilation was longer;the incidence rates of pulmonary hypertension and intrauterine infection were higher than those in the early preterm group.Conclusion LP infants with RDS are mainly dominated by cesarean section without onset of labor process,intrauterine infection may be its risk factor,PS use is effective,but its effect is more poor than that in the early preterm group,the mechanical ventilation rate in the LP group is higher,but the prognosis is good.

Background and purpose: Accumulating evidence has revealed that long non-coding RNA (lncRNA) is correlated with carcinogenesis and tumor development. Recent literature suggested that lncRNA promoter of CDKN1A antisense DNA damage activated RNA (PANDAR) was involved in the development of various cancers. However, the functional role of PANDAR in colorectal cancer (CRC) has not been elucidated yet. The present study aimed to explore the functional role of lncRNA PANDAR in promoting CRC metastasis and its mechanism.Methods: The expression of lncRNA PANDAR in CRC cell lines and tissues was detected by real-time fluorescent quantitative polymerase chain reaction (RTFQ-PCR), and the correlation between lncRNA PANDAR expression and CRC clinicopathological characteristics was statistically analyzed. Then, lncRNA PANDAR stably silencing CRC cells (HCT116-shPANDAR), overexpression cells (DLD1-PANDAR) and control vector cells (HCT116-shNC and DLD1-vector) were established using lentiviral vectors. Moreover, Transwell assay and Matrigel assay were performed to investigate the function of lncRNA PANDAR in CRC migration and invasion. Furthermore, the expression of transcriptional factors mediating epithelial-mesenchymal transition of lncRNA PANDAR overexpression cells were monitored by RTFQ-PCR assay, and the function of the target gene in modulating lncRNA PANDAR mediated CRC metastasis was also explored. Results: The expression levels of lncRNA PANDAR in normal colorectal epithelial cells were much lower than in CRC cell. The levels of lncRNA PANDAR in tumor-adjacent tissues were verified to be much lower than in CRC tissues [(171.52±97.80)% vs (100.00±63.18)%, P<0.05]. Moreover, the expression of lncRNA PANDAR was detected to be significantly correlated with CRC TNM stage, lymph node metastasis and distant metastasis (P<0.05). Besides, lncRNA PANDAR deficiency significantly reduced the migration [100.00% vs (42.08±4.77)%, P<0.05] and invasion [100.00% vs (39.14±3.81)%, P<0.05] capabilities in CRC cells, in contrast, the migration [100.00% vs (194.12±9.33)%, P<0.05] and invasion [100.00% vs (204.08±12.27)%, P<0.05] capa-bilities of CRC cells were obviously increased with lncRNA PANDAR overexpression. Furthermore, zinc-finger E-box binding homeobox 1 (ZEB1) expression was detected to be positively correlated with lncRNA PANDAR expression, and ZEB1 silencing could significantly reverse the increased migration and invasion capabilities induced by lncRNA PANDAR in CRC cells. Conclusion: LncRNA PANDAR could promote CRC metastasis by potentially targeting ZEB1. LncRNA PANDAR might be a promising diagnostic marker and therapeutic target for CRC patients.

Objective To investigate the expression of neuron-specific enolase(NSE) and bone morphogenic protein 4(BMP4) in different hippocampal areas of pentylenetetrazol(PTZ) kindled epilepsy rats and explore their relationship with the pathogenesis of epilepsy and brain injury.Methods Fifty male SD rats were divided into experimental group(n=40) and control group(n=10).The rats in experimental group were kindled into epilepsy by chemical method,and according to the kindling process,subdivided into four groups(grade Ⅰ,Ⅲ,Ⅳ,Ⅴ).Immunohistochemistry,in situ hybridization labeled with Dig-oligonucleotide probe and the image analyzing system were used to observe the expressions of NSE and BMP4 in rat hippocampus.Results In PTZ kindled epilepsy rats,the number of cells positive for NSE and BMP4 was increased in many regions of hippocampal formation.Compared with control group,the expressions of NSE and BMP4 in CA3 and DG was elevated obviously in the grade Ⅲ group and grade Ⅳ group(P

Collagen is a major structural protein in the matrix of animal cells and the most widely distributed and abundant functional protein in mammals. Collagen’s good biocompatibility, biodegradability and biological activity make it a very valuable biomaterial. According to the source of collagen, it can be broadly categorized into two types: one is animal collagen; the other is recombinant collagen. Animal collagen is mainly extracted and purified from animal connective tissues by chemical methods, such as acid, alkali and enzyme methods, etc. Recombinant collagen refers to collagen produced by gene splicing technology, where the amino acid sequence is first designed and improved according to one’s own needs, and the gene sequence of improved recombinant collagen is highly consistent with that of human beings, and then the designed gene sequence is cloned into the appropriate vector, and then transferred to the appropriate expression vector. The designed gene sequence is cloned into a suitable vector, and then transferred to a suitable expression system for full expression, and finally the target protein is obtained by extraction and purification technology. Recombinant collagen has excellent histocompatibility and water solubility, can be directly absorbed by the human body and participate in the construction of collagen, remodeling of the extracellular matrix, cell growth, wound healing and site filling, etc., which has demonstrated significant effects, and has become the focus of the development of modern biomedical materials. This paper firstly elaborates the structure, type, and tissue distribution of human collagen, as well as the associated genetic diseases of different types of collagen, then introduces the specific process of producing animal source collagen and recombinant collagen, explains the advantages of recombinant collagen production method, and then introduces the various systems of expressing recombinant collagen, as well as their advantages and disadvantages, and finally briefly introduces the application of animal collagen, focusing on the use of animal collagen in the development of biopharmaceutical materials. In terms of application, it focuses on the use of animal disease models exploring the application effects of recombinant collagen in wound hemostasis, wound repair, corneal therapy, female pelvic floor dysfunction (FPFD), vaginal atrophy (VA) and vaginal dryness, thin endometritis (TE), chronic endometritis (CE), bone tissue regeneration in vivo, cardiovascular diseases, breast cancer (BC) and anti-aging. The mechanism of action of recombinant collagen in the treatment of FPFD and CE was introduced, and the clinical application and curative effect of recombinant collagen in skin burn, skin wound, dermatitis, acne and menopausal urogenital syndrome (GSM) were summarized. From the exploratory studies and clinical applications, it is evident that recombinant collagen has demonstrated surprising effects in the treatment of all types of diseases, such as reducing inflammation, promoting cell proliferation, migration and adhesion, increasing collagen deposition, and remodeling the extracellular matrix. At the end of the review, the challenges faced by recombinant collagen are summarized: to develop new recombinant collagen types and dosage forms, to explore the mechanism of action of recombinant collagen, and to provide an outlook for the future development and application of recombinant collagen.