I. Dueramae, Shingo Fukuzawa, N. Shinyashiki, S. Yagihara, R. Kita
We investigated the mechanisms of amyloidlike aggregation and gel formation in hen egg-white lysozyme (HEWL) in a mixed solvent comprising 90% v/v ethanol in water using dynamic light scattering (DLS) and circular dichroism CD. The mechanism of HEWL in ethanol aqueous solution is interpreted into three stages as: (I) denaturation of HEWL; (II) elongation of amyloid fibrils composed of β-sheet-rich HEWL by lateral aggregation; and (III) gel formation due to the creation of junctions in amyloid fibrils. The transformation of sol to gel can be confirmed by: (1) the oscillation behavior and the rapid increase in the intensity of scattered light; (2) the power-law behavior of the correlation function of scattered light g(2)(t); (3) the appearance of a long-time tail in the distribution function of the decay time G(τ); and (4) the beginning of the reduction in initial amplitude in g(2)(t). The gelation rate was strongly dependent on the protein concentration. The estimated rod length of the amyloid fibrils increased significantly over time. Scanning electron microscopy (SEM) performed on the formation of fibrils in the HEWL gels revealed that the structure was highly heterogeneous, with areas characterized by dense fiber networks interspersed with loose network areas.
{"title":"Dynamics of amyloid-like aggregation and gel formation of hen egg-white lysozyme in highly concentrated ethanol solution","authors":"I. Dueramae, Shingo Fukuzawa, N. Shinyashiki, S. Yagihara, R. Kita","doi":"10.17106/JBR.31.21","DOIUrl":"https://doi.org/10.17106/JBR.31.21","url":null,"abstract":"We investigated the mechanisms of amyloidlike aggregation and gel formation in hen egg-white lysozyme (HEWL) in a mixed solvent comprising 90% v/v ethanol in water using dynamic light scattering (DLS) and circular dichroism CD. The mechanism of HEWL in ethanol aqueous solution is interpreted into three stages as: (I) denaturation of HEWL; (II) elongation of amyloid fibrils composed of β-sheet-rich HEWL by lateral aggregation; and (III) gel formation due to the creation of junctions in amyloid fibrils. The transformation of sol to gel can be confirmed by: (1) the oscillation behavior and the rapid increase in the intensity of scattered light; (2) the power-law behavior of the correlation function of scattered light g(2)(t); (3) the appearance of a long-time tail in the distribution function of the decay time G(τ); and (4) the beginning of the reduction in initial amplitude in g(2)(t). The gelation rate was strongly dependent on the protein concentration. The estimated rod length of the amyloid fibrils increased significantly over time. Scanning electron microscopy (SEM) performed on the formation of fibrils in the HEWL gels revealed that the structure was highly heterogeneous, with areas characterized by dense fiber networks interspersed with loose network areas.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"31 1","pages":"21-28"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.17106/JBR.31.21","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68196423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Takagi, Susumu Tanaka, Syo Tomita, Shuri Akiyama, Y. Maki, Takao Yamamoto, Masumi Uehara, T. Dobashi
A gelatin gel sheet was UV-irradiated to raise the gel melting temperature Tm. Three second of Tm increased proportionally to irradiation time tUV. The sheet of which Tm was larger than the culture temperature 37°C was used as a cell culture scaffold. Human fibroblast cells WI-38 adhered to the sheet and dug deeply into it regardless of tUV, while cancer cells WI-38-VA-13 formed spheroids and did not adhere to the sheet individually at high UV dose. The cell selectivity of the scaffold could be used for biological and medical studies.
对明胶凝胶片进行紫外照射，提高凝胶的熔化温度Tm。三秒Tm随辐照时间的增加而增加。将Tm大于培养温度37℃的薄片作为细胞培养支架。人成纤维细胞WI-38无论在多大的紫外线照射下都能粘附在薄片上，并深入到薄片上，而癌细胞WI-38- va -13在高紫外线照射下形成球状体，并不能单独粘附在薄片上。该支架的细胞选择性可用于生物学和医学研究。
{"title":"Preparation of gelatin scaffold and fibroblast cell culture","authors":"Y. Takagi, Susumu Tanaka, Syo Tomita, Shuri Akiyama, Y. Maki, Takao Yamamoto, Masumi Uehara, T. Dobashi","doi":"10.17106/JBR.31.2","DOIUrl":"https://doi.org/10.17106/JBR.31.2","url":null,"abstract":"A gelatin gel sheet was UV-irradiated to raise the gel melting temperature Tm. Three second of Tm increased proportionally to irradiation time tUV. The sheet of which Tm was larger than the culture temperature 37°C was used as a cell culture scaffold. Human fibroblast cells WI-38 adhered to the sheet and dug deeply into it regardless of tUV, while cancer cells WI-38-VA-13 formed spheroids and did not adhere to the sheet individually at high UV dose. The cell selectivity of the scaffold could be used for biological and medical studies.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"31 1","pages":"2-5"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.17106/JBR.31.2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68196369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fibrinogen is converted to fibrin monomer and forms a three-dimensional gel network in a step wise manner by the enzymatic action of thrombin (thrombin-induced fibrin gelation). On the other hand, when a fibrinogen solution is incubated at low temperatures (e.g. below 4°C), it is converted to a gel without thrombin. The fibrinogen gel induced by lowering temperature is called “cryogel” and is closely related to some diseases. However, the mechanism of fibrinogen cryogelation has not been understood yet. In this study, the effects of urea and NaCl on fibrinogen cryogelation and thrombin-induced fibrin gelation have been studied turbidimetrically. The addition of urea retarded both gelation, and the extent of retardation increased with increasing the concentration of urea. The effects of urea on fibrinogen cryogelation were much larger than those on thrombin-induced fibrin gelation, and fibrinogen cryogelation was completely inhibited by the addition of 150 mM urea. The addition of NaCl retarded fibrinogen cryogelation with increasing the concentration of NaCl. By contrast, the effects of NaCl on thrombin-induced fibrin gelation were only limited. Based on the experimental results, the contributions of hydrogen and ionic bonds to each gelation are discussed.
{"title":"Effects of urea and NaCl on the fibrinogen cryogelation","authors":"Y. Toyama, M. Shimizu, M. Ochiai, T. Dobashi","doi":"10.17106/JBR.31.12","DOIUrl":"https://doi.org/10.17106/JBR.31.12","url":null,"abstract":"Fibrinogen is converted to fibrin monomer and forms a three-dimensional gel network in a step wise manner by the enzymatic action of thrombin (thrombin-induced fibrin gelation). On the other hand, when a fibrinogen solution is incubated at low temperatures (e.g. below 4°C), it is converted to a gel without thrombin. The fibrinogen gel induced by lowering temperature is called “cryogel” and is closely related to some diseases. However, the mechanism of fibrinogen cryogelation has not been understood yet. In this study, the effects of urea and NaCl on fibrinogen cryogelation and thrombin-induced fibrin gelation have been studied turbidimetrically. The addition of urea retarded both gelation, and the extent of retardation increased with increasing the concentration of urea. The effects of urea on fibrinogen cryogelation were much larger than those on thrombin-induced fibrin gelation, and fibrinogen cryogelation was completely inhibited by the addition of 150 mM urea. The addition of NaCl retarded fibrinogen cryogelation with increasing the concentration of NaCl. By contrast, the effects of NaCl on thrombin-induced fibrin gelation were only limited. Based on the experimental results, the contributions of hydrogen and ionic bonds to each gelation are discussed.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"31 1","pages":"12-15"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68196298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shinichi Goto, N. Tamura, K. Ayabe, E. Kato, Terumitsu Hasebe, S. Takagi, Yota Kawamura, Shinya Goto
Formation of thrombi is a complex biological event involving platelets and coagulation cascades. The both have been well investigated individually. However, the interrelationship between them is still to be elucidated. The recent progresses in computer technology may allow us to simulate complex biological phenomena in silico. Here we report a novel method to reproduce the complex system of the interrelationship between platelet and coagulation by combining the previous simulation model of platelet adhesion with the model of coagulation cascade. We have reproduced the biological process of thrombus growth occurring in the mice cremasteric artery induced by endothelial injury by FeCl3 with our newly developed computer simulator.
{"title":"A method and preliminary results of in silico computer simulation for the formation of mix thrombi with platelet and fibrin","authors":"Shinichi Goto, N. Tamura, K. Ayabe, E. Kato, Terumitsu Hasebe, S. Takagi, Yota Kawamura, Shinya Goto","doi":"10.17106/JBR.31.30","DOIUrl":"https://doi.org/10.17106/JBR.31.30","url":null,"abstract":"Formation of thrombi is a complex biological event involving platelets and coagulation cascades. The both have been well investigated individually. However, the interrelationship between them is still to be elucidated. The recent progresses in computer technology may allow us to simulate complex biological phenomena in silico. Here we report a novel method to reproduce the complex system of the interrelationship between platelet and coagulation by combining the previous simulation model of platelet adhesion with the model of coagulation cascade. We have reproduced the biological process of thrombus growth occurring in the mice cremasteric artery induced by endothelial injury by FeCl3 with our newly developed computer simulator.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"31 1","pages":"30-34"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68196681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Transitions in the in-vivo visualisation of renal physiology","authors":"H. Nakamoto","doi":"10.17106/JBR.31.40","DOIUrl":"https://doi.org/10.17106/JBR.31.40","url":null,"abstract":"","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"31 1","pages":"40-43"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68197043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Paphawee Nantarajit, Natdanai Fafaungwithayakul, Natsuda Vichakacharu, S. Matsukawa
We have elucidated the heat induced formation of wormlike micelles in the mixture solutions containing two different geometric amphiphiles of lysophosphatidylcholine (LPC) and phosphatidylcholine (PC), where LPC and PC have one and two alkyl chains as hydrophobic groups, respectively. The mixture solutions showed the increases in viscosity and transparency by heating, and showed the highest viscosity at the ratio of LPC/PC = 1.67, suggesting the formation of long wormlike micelles attained by the average cpp around 0.5 favorable. From the dynamic rheological measurements, it was found that the elasticity was proportional to the square of total concentration of LPC and PC, indicating the existence of entanglement among long wormlike micelles. Other mixture solutions seem to be mixtures of spherical, lamellar and wormlike micelles with different sizes judging from the viscoelastic behavior and transparency, where the sizes changed reversibly with the temperature changes.
{"title":"Rheological properties in solutions of wormlike micelle composed of lysophosphatidylcholine/phosphatidylcholine mixture","authors":"Paphawee Nantarajit, Natdanai Fafaungwithayakul, Natsuda Vichakacharu, S. Matsukawa","doi":"10.17106/JBR.31.44","DOIUrl":"https://doi.org/10.17106/JBR.31.44","url":null,"abstract":"We have elucidated the heat induced formation of wormlike micelles in the mixture solutions containing two different geometric amphiphiles of lysophosphatidylcholine (LPC) and phosphatidylcholine (PC), where LPC and PC have one and two alkyl chains as hydrophobic groups, respectively. The mixture solutions showed the increases in viscosity and transparency by heating, and showed the highest viscosity at the ratio of LPC/PC = 1.67, suggesting the formation of long wormlike micelles attained by the average cpp around 0.5 favorable. From the dynamic rheological measurements, it was found that the elasticity was proportional to the square of total concentration of LPC and PC, indicating the existence of entanglement among long wormlike micelles. Other mixture solutions seem to be mixtures of spherical, lamellar and wormlike micelles with different sizes judging from the viscoelastic behavior and transparency, where the sizes changed reversibly with the temperature changes.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"31 1","pages":"44-49"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.17106/JBR.31.44","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68197150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"For the “Special Issue on the 40th Annual Meeting of Japanese Society of Biorheology”","authors":"T. Ohashi","doi":"10.17106/JBR.31.29","DOIUrl":"https://doi.org/10.17106/JBR.31.29","url":null,"abstract":"","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"31 1","pages":"29-29"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68196476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shunsuke Yoda, T. Yokoyama, Mitsuhiro Fukata, T. Arita, K. Odashiro, T. Maruyama, K. Akashi
Erythrocyte deformability plays a key role in pulmonary microcirculation, which raised the hypothesis that erythrocyte deformability is impaired in pulmonary thromboembolism (PTE) and subsequent chronic thromboembolic pulmonary hypertension (CTEPH). We encoun-tered a case of PTE followed by CTEPH and investigated erythrocyte deformability by our specified filtration technique to test this hypothesis. Erythrocyte deformability was normal before but was impaired after the onset of PTE. It was restored partially in the stage of CTEPH. This case taught us that erythrocyte deformability is impaired and that this impairment relates to the hemodynamics of pulmonary microcirculation and pathophysiology of PTE and CTEPH.
{"title":"Assessment of erythrocyte deformability in an obese case of chronic thromboembolic pulmonary hypertension","authors":"Shunsuke Yoda, T. Yokoyama, Mitsuhiro Fukata, T. Arita, K. Odashiro, T. Maruyama, K. Akashi","doi":"10.17106/JBR.31.57","DOIUrl":"https://doi.org/10.17106/JBR.31.57","url":null,"abstract":"Erythrocyte deformability plays a key role in pulmonary microcirculation, which raised the hypothesis that erythrocyte deformability is impaired in pulmonary thromboembolism (PTE) and subsequent chronic thromboembolic pulmonary hypertension (CTEPH). We encoun-tered a case of PTE followed by CTEPH and investigated erythrocyte deformability by our specified filtration technique to test this hypothesis. Erythrocyte deformability was normal before but was impaired after the onset of PTE. It was restored partially in the stage of CTEPH. This case taught us that erythrocyte deformability is impaired and that this impairment relates to the hemodynamics of pulmonary microcirculation and pathophysiology of PTE and CTEPH.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"31 1","pages":"57-60"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68196825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"For the Special Issue “Structural formation of biological materials and their use in science and technology”","authors":"R. Kita","doi":"10.17106/JBR.31.1","DOIUrl":"https://doi.org/10.17106/JBR.31.1","url":null,"abstract":"","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"31 1","pages":"1-1"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68196290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We study thermo-structural behavior of anionic lipid 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) dispersed systems. Continuous chain-melting transition of DMPG induces anomalous intermediate phase between gel and fluid phases. We found that the intermediate phase can be divided into two domains; anisotropic phase with high orientational order and isotropic viscous phase. Anisotropic phase would be identified to perforated lamellae or bicelle formed by rupturing the perforated vesicles under shear. Isotropic viscous phase, on the other hand, might be identified to densely packed perforated vesicle dispersions formed by rearranging extended bilayer membranes.
{"title":"Rheological characterization of thermal phase behavior of anionic lipid DMPG dispersions","authors":"S. Fujii","doi":"10.17106/JBR.31.6","DOIUrl":"https://doi.org/10.17106/JBR.31.6","url":null,"abstract":"We study thermo-structural behavior of anionic lipid 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) dispersed systems. Continuous chain-melting transition of DMPG induces anomalous intermediate phase between gel and fluid phases. We found that the intermediate phase can be divided into two domains; anisotropic phase with high orientational order and isotropic viscous phase. Anisotropic phase would be identified to perforated lamellae or bicelle formed by rupturing the perforated vesicles under shear. Isotropic viscous phase, on the other hand, might be identified to densely packed perforated vesicle dispersions formed by rearranging extended bilayer membranes.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"113 1","pages":"6-11"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68196894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：