Ground type-I collagen—a focused study on its fibrillogenesis behavior and bioactivity in vitro

Yuling Xu,Lei Dai,Ke Li,Jialin Liu,Haibo Wang,Lang He,Chengzhi Xu,Benmei Wei,Juntao Zhang 한국고분자학회 2023 Macromolecular Research Vol.31 No.1

Take bovine tendon type-I collagen as the raw material, we pretreated it by freezing and then grinding the macromolecule at a low temperature (4–10 °C). Effects of the grinding process on the molecular structure, water solubility, fibrillogenesis behavior in vitro and biological activity of collagen were systematically prospected. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) results revealed that the collagen had typical structural characteristics of type-I collagen; moreover, grinding treatment gave rise to partially degraded collagen molecules which took on continuous bands with lower molecular weights different from α1 and α2. More strikingly, the degradation degree positively corresponded to the grinding duration. Circular dichroism (CD) analysis manifested that with extended grinding, intensities of both the positive and negative peaks for collagen samples shrunk. Interestingly, grinding also contributed to improved water solubility of collagen. The water solubility of the sample ground for 20 min (COL20) was 1.91 mg/mL, which is about 6 times higher than that of the natural collagen sample (0.28 mg/mL). Amid the study concerning the fibrillogenesis behavior, turbidity and rheological data collaboratively demonstrated that with prolonged grinding time, the assembly rate and degree of the sample plunged. Assembled gel from the ground collagen with finer fibrils was also observed in scanning electron microscope (SEM), which further embraced the conclusion aforementioned in fibrillogenesis kinetics. Cell experiments corroborated that the grinding process can be harnessed to manipulate the cell proliferation promoting ability of collagen. Simultaneously, further dissection of COL20 with the best biological activity clarified that the water-soluble part and water-insoluble part of COL20 had distinct aptitudes as to promoting cell proliferation as well as inhibiting the growth of liver cancer cells.

Weather Forecasting Using Ensemble of Spatial-Temporal Attention Network and Multi-Layer Perceptron

Yuanpeng Li,Junwei Lang,Lei Ji,Jiqin Zhong,Zaiwen Wang,Yang Guo,Sailing He 한국기상학회 2021 Asia-Pacific Journal of Atmospheric Sciences Vol.57 No.3

Weather forecasting is a challenging task, which is especially suited for artificial intelligence due to the large amount of data involved. This paper proposed an end-to-end hybrid regression model, called Ensemble of Spatial-Temporal Attention Network and Multi-Layer Perceptron (E-STAN-MLP), to forecast surface temperature, humidity, wind speed, and wind direction at 24 automatic weather stations in Beijing. Combining the data from historical observations with the data from the numerical weather prediction (NWP) system, our proposed model give better results than the NWP system or previously reported algorithms. Our E-STAN-MLP model consists of two parts. One is to use the spatial-temporal attention based recurrent neural network to model the time series of meteorological elements. The other is a simple but efficient multilayer perceptron architecture forecasts the regression value while ignoring time dependence. Results at each time stamp are integrated together using a step-wise fusion strategy. Moreover, we use a joint loss step integrating both the regression loss function and the classification loss function to simultaneously forecast the wind speed and direction. Experiments demonstrate that our proposed E-STAN-MLP model achieves state-of-the-art results in weather forecasting.

Investigating the effects of a range shifter on skin dose in proton therapy

Wang Ming,Zhang Lei,Zheng Jinxing,Li Guodong,Dai Wei,Dong Lang 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.1

Proton treatment may deliver a larger dose to a patient’s skin than traditional photon therapy, especially when a range shifter (RS) is inserted in the beam path. This study investigated the effects of an RS on skin dose while considering RS with different thicknesses, airgaps and materials. First, the physical model of the scanning nozzle with RS was established in the TOol for PArticle Simulation (TOPAS) code, and the effects of the RS on the skin dose were studied. Second, the variations in the skin dose and isocenter beam size were examined by reducing the air gap. Finally, the effects of different RS materials, such as polymethylmethacrylate (PMMA), Lexan, polyethylene and polystyrene, on the skin dose were analysed. The results demonstrated that the current RS design had a negligible effect on the skin dose, whereas the RS significantly impacted the isocenter beam size. The skin dose was increased considerably when the RS was placed close to the phantom. Moreover, the magnitude of the increase was related to the thickness of the inserted RS. Meanwhile, the results also revealed that the secondary proton primarily contributed to the increased skin dose.

Proteomic analysis of Cry1Ac and Cry2Aa binding proteins in brush border membrane vesicles of the Chilo suppressalis midgut

Lin Qiu,Peipei Wang,Boyao Zhang,Lang Liu,Xiaoping Wang,Chaoliang Lei,Yongjun Lin,Weihua Ma 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.4

Transgenic rice expressing Bacillus thuringiensis (Bt) Cry1Ac and Cry2Aa toxins have proven resistant to lepidopteran pests in China, including the striped stem borer, Chilo suppressalis. Identifying the molecular mechanisms through which Cry toxins affect insect pests is essential, both for understanding the nature of their toxicity, and for assessing the potential for the development of resistance to such toxins. In this study, both onedimensional gel electrophoresis (1-DE), combined ligand blots and mass spectrometry, were used to identify proteins binding to the Cry1Ac and Cry2Aa toxins in brush border membrane vesicles (BBMVs) of the C. suppressalis larvae midgut. Aminopeptidase-N (APN), alkaline phosphatase (ALP), cadherin-like (CAD), ATP-binding cassette transporter subfamily C1 protein (ABCC1), actin, ATPase, alpha amylase, and heat shock protein cognate (HSPC), were detected in Cry1Ac binding bands, and APN, actin, ATPase and HSPC were identified as Cry2Aa potential binding proteins. The novel potential binding protein, delta-aminolevulinic acid dehydratase, was also detected in both Cry1Ac and Cry2Aa binding bands. This is the first study to comprehensively identify the proteins that bind to Cry1Ac and Cry2Aa toxins in C. suppressalis.

Design of potent, non-toxic anticancer peptides based on the structure of the antimicrobial peptide, temporin-1CEa

Qing-Zhu Yang,Che Wang,Lei Lang,Yang Zhou,He Wang,De-Jing Shang 대한약학회 2013 Archives of Pharmacal Research Vol.36 No.11

Recent advances in the search for novel anticanceragents have indicated that the positively chargedantimicrobial peptides have emerged as promising agentsoffering several advantages over the conventional anticancerdrugs. As a naturally occurring, cationic, a-helicalantimicrobial peptide, temproin-1CEa has been proved toexhibit a potent anticancer effect and a moderate hemolyticactivity. In order to reduce the hemolytic activity of temporin-1CEa and improve its anticancer potency towards arange of human breast cancer cells, in the present study, sixanalogs of temporin-1CEa were rationally designed andsynthesized. The amphipathicity levels and a-helicalstructural patterns of peptides were reserved, while theircationic property and hydrophobicity were changed. Theresults of MTT and hemolysis assay indicated that theanalog peptides displayed an improved anticancer activityand showed an overall optimized therapeutic index. Thehydrophobicity of peptides was positively correlated withtheir hemolytic and antitumor activities. Moreover, the datasuggest a strategy of increasing the cationicity whilemaintaining the moderate hydrophobicity of naturallyoccurring amphipathic a-helical peptides to generate analogswith improved cytotoxicity against tumor cells butdecreased activity against non-neoplastic cells such ashuman erythrocytes. This work highlights the potential forrational design and synthesis of improved antimicrobialpeptides that have the capability to be used therapeuticallyfor treatment of cancers.

Calcium/Calmodulin-dependent Serine Protein Kinase-associated Neuro-gastrointestinal Disorder: First Report of a Patient With Hirschsprung‘s Disease

( Maoqiang Tian ),( Hong Pan ),( Wenting Lei ),( Jing Chen ),( Juan Li ),( Changhui Lang ),( Xiaomei Shu ) 대한소화기기능성질환·운동학회(구 대한소화관운동학회) 2020 Journal of Neurogastroenterology and Motility (JNM Vol.26 No.4

The Stent-Assisted Coil-Jailing Technique Facilitates Efficient Embolization of Tiny Cerebral Aneurysms

Cong-Hui Li,Xian-Hui Su,Bo Zhang,Yong-Feng Han,Er-Wei Zhang,Lei Yang,Dong-Liang Zhang,Song-Tao Yang,Zhen-Quan Yan,Bu-Lang Gao 대한영상의학회 2014 Korean Journal of Radiology Vol.15 No.6

Objective: Tiny cerebral aneurysms are difficult to embolize because the aneurysm’s sac is too small for a single small coil, and coils within the aneurysm may escape from the confinement of a stent. This study was performed to introduce the stent-assisted coil-jailing technique and to investigate its effect on the coil embolization of tiny intracranial aneurysms. Materials and Methods: Sixteen patients with tiny intracranial aneurysms treated with the stent-assisted coil-jailing technique between January 2011 and December 2013 were retrospectively reviewed and followed-up. Results: All aneurysms were successfully treated with the coil-jailing technique, and at the end of embolization, complete occlusion of the aneurysm was achieved in 9 cases (56.3%), incomplete occlusion in 6 (37.5%), and partial occlusion in 1 (6.3%). Intraprocedural complications included acute thrombosis in one case (6.3%) and re-rupture in another (6.3%). Both complications were managed appropriately with no sequela. Follow-up was performed in all patients for 3–24 months (mean, 7.7 months) after embolization. Complete occlusion was sustained in the 9 aneurysms with initial complete occlusion, progressive thrombosis to complete occlusion occurred in the 6 aneurysms with initial near-complete occlusion, and one aneurysm resulted in progressive thrombosis to complete occlusion after initial partial occlusion. No migration of stents or coils occurred at follow-up as compared with their positions immediately after embolization. At follow-up, all patients had recovered with no sequela. Conclusion: The stent-assisted coil-jailing technique can be an efficient approach for tiny intracranial aneurysms, even though no definite conclusion regarding its safety can be drawn from the current data.