Background: Protein adsorption on medical devices in contact with blood is a significant issue during renal replacement therapy. Main forces determining fouling are the electrostatic interactions between membrane and charged protein, but the dialysis membrane surface charges can be adjusted by modifying the polymer matrix to decrease the blood plasma protein adsorption.
Methods: In this study, polysulfone membranes (PSU) were modified by incorporation of carbon nanoparticles such as: multiwall carbon nanotubes (2 wt.% MWCNT), graphene oxide (1 wt.% GO), and graphite (5 wt.% GR) during manufacturing process (nonsolvent-induced phase separation, NIPS). The PSU flat sheet membrane was the reference sample.
Results: Observed morphology of nanocomposite membranes was similar (SEM imaging); all of them had finger-like pore structure with unimodal distribution of pore size and similar skin-to-support ratio (1:3). The carbon nanoadditives also influenced the surface wettability: hydrophobicity and surface free energy of membranes increased (polar components of energy were reduced, while the dispersive components were increased).
Conclusion: The surface charge of nanocomposite membranes increased, when the polymer matrix has been modified with CNT or GR. This significantly affects the adsorption of proteins such as chicken (CSA) and bovine serum albumin (BSA) and reduces blood clotting on the membrane.
背景:蛋白质吸附在与血液接触的医疗设备上是肾脏替代治疗过程中的一个重要问题。决定污垢产生的主要因素是膜与带电蛋白质之间的静电相互作用,但透析膜表面的电荷可通过改性聚合物基质来调整,以减少血浆蛋白质的吸附:本研究在聚砜膜(PSU)的制造过程中加入了碳纳米颗粒,如:多壁碳纳米管(2 wt.% MWCNT)、氧化石墨烯(1 wt.% GO)和石墨(5 wt.% GR)(非溶剂诱导相分离,NIPS)。PSU 平板膜为参考样品:观察到的纳米复合膜形态相似(扫描电子显微镜成像);所有纳米复合膜都具有指状孔隙结构,孔隙大小呈单峰分布,表皮与支撑物的比例相似(1:3)。碳纳米添加剂还影响了表面润湿性:膜的疏水性和表面自由能增加(能量的极性成分减少,而分散成分增加):结论:用 CNT 或 GR 对聚合物基质进行改性后,纳米复合膜的表面电荷增加。结论:用 CNT 或 GR 对聚合物基质进行改性后,纳米复合膜的表面电荷增加,这极大地影响了膜对鸡肉(CSA)和牛血清白蛋白(BSA)等蛋白质的吸附,并减少了膜上的血液凝结。
{"title":"Dialysis nanocomposite membranes based on carbon nanoforms inhibiting blood plasma protein adsorption.","authors":"Dominika Wójtowicz, Roksana Kurpanik, Dominika Nguyen Ngoc, Joanna Wessley-Szponder, Ewa Stodolak-Zych","doi":"10.1177/03913988241269440","DOIUrl":"https://doi.org/10.1177/03913988241269440","url":null,"abstract":"<p><strong>Background: </strong>Protein adsorption on medical devices in contact with blood is a significant issue during renal replacement therapy. Main forces determining fouling are the electrostatic interactions between membrane and charged protein, but the dialysis membrane surface charges can be adjusted by modifying the polymer matrix to decrease the blood plasma protein adsorption.</p><p><strong>Methods: </strong>In this study, polysulfone membranes (PSU) were modified by incorporation of carbon nanoparticles such as: multiwall carbon nanotubes (2 wt.% MWCNT), graphene oxide (1 wt.% GO), and graphite (5 wt.% GR) during manufacturing process (nonsolvent-induced phase separation, NIPS). The PSU flat sheet membrane was the reference sample.</p><p><strong>Results: </strong>Observed morphology of nanocomposite membranes was similar (SEM imaging); all of them had finger-like pore structure with unimodal distribution of pore size and similar skin-to-support ratio (1:3). The carbon nanoadditives also influenced the surface wettability: hydrophobicity and surface free energy of membranes increased (polar components of energy were reduced, while the dispersive components were increased).</p><p><strong>Conclusion: </strong>The surface charge of nanocomposite membranes increased, when the polymer matrix has been modified with CNT or GR. This significantly affects the adsorption of proteins such as chicken (CSA) and bovine serum albumin (BSA) and reduces blood clotting on the membrane.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142017345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-22DOI: 10.1177/03913988241269524
Yanyan Gong, Menglin Zou, Laimin Luo
Objective: To construct a prediction model of coagulation in the extracorporeal circulation circuit during hemodialysis with regional citrate anticoagulant(RCA) conditions.
Methods: This was a single-center, retrospective study. The clinical data of patients who received hemodialysis with RCA from February 2021 to March 2022 were collected. The risk predictors of coagulation in the extracorporeal circulation circuit were screened by LASSO regression. On this basis, we used multivariate logistic regression analysis to establish a nomogram prediction model.
Results: A total of 98 patients received RCA hemodialysis for 362 times. Among them, 155 treatments with complete data were included in the study. Among the 155 treatments, coagulation of the extracorporeal circulation circuit occurred 12 times. The use of arteriovenous fistulas(AVF), the venous pressure at 4 h after hemodialysis initiation, blood flow velocity, dialyzer manufacturer, Systemic iCa2+ at 1 h after hemodialysis initiation, plasma albumin level, and plasma d-dimer level were influencing factors of coagulation in the extracorporeal circuit during hemodialysis with RCA (p < 0.05). A nomogram model was made out of the above indicators. The area under the receiver operating characteristic (ROC) curve for predicting coagulation in the circuit was 0.967 (95% CI: 0.935-0.998). The internal validation result of the memory testing (bootstrap method) showed that the area under the ROC curve was 0.967 (95% CI: 0.918-0.991).
Conclusion: The nomogram model has good discrimination and calibration and can intuitively and succinctly predict the risk of coagulation in the extracorporeal circulation circuit during hemodialysis with RCA.
{"title":"Construction of a coagulation prediction model of the extracorporeal circulation circuit during hemodialysis with regional citrate anticoagulant (RCA).","authors":"Yanyan Gong, Menglin Zou, Laimin Luo","doi":"10.1177/03913988241269524","DOIUrl":"https://doi.org/10.1177/03913988241269524","url":null,"abstract":"<p><strong>Objective: </strong>To construct a prediction model of coagulation in the extracorporeal circulation circuit during hemodialysis with regional citrate anticoagulant(RCA) conditions.</p><p><strong>Methods: </strong>This was a single-center, retrospective study. The clinical data of patients who received hemodialysis with RCA from February 2021 to March 2022 were collected. The risk predictors of coagulation in the extracorporeal circulation circuit were screened by LASSO regression. On this basis, we used multivariate logistic regression analysis to establish a nomogram prediction model.</p><p><strong>Results: </strong>A total of 98 patients received RCA hemodialysis for 362 times. Among them, 155 treatments with complete data were included in the study. Among the 155 treatments, coagulation of the extracorporeal circulation circuit occurred 12 times. The use of arteriovenous fistulas(AVF), the venous pressure at 4 h after hemodialysis initiation, blood flow velocity, dialyzer manufacturer, Systemic iCa<sup>2+</sup> at 1 h after hemodialysis initiation, plasma albumin level, and plasma d-dimer level were influencing factors of coagulation in the extracorporeal circuit during hemodialysis with RCA (<i>p</i> < 0.05). A nomogram model was made out of the above indicators. The area under the receiver operating characteristic (ROC) curve for predicting coagulation in the circuit was 0.967 (95% CI: 0.935-0.998). The internal validation result of the memory testing (bootstrap method) showed that the area under the ROC curve was 0.967 (95% CI: 0.918-0.991).</p><p><strong>Conclusion: </strong>The nomogram model has good discrimination and calibration and can intuitively and succinctly predict the risk of coagulation in the extracorporeal circulation circuit during hemodialysis with RCA.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142017344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-22DOI: 10.1177/03913988241269498
Tong Wu, Lei Han, Ye Zhu, Xiaojun Zeng, Yating Kang, Shuwen Zheng, Zhenhai Wang, Jianping Wang, Yonglin Gao
Aim: The optimal preparation conditions of Salmon decalcified bone matrix (S-DBM) were explored, and the properties of S-DBM bone particles and bone powder were studied respectively. The therapeutic effect of S-DBM on tibial defect in female Sprague Dawley (SD) rats was preliminarily verified.
Methods: This study assessed the structural and functional similarities of Salmon bone DBM (S-DBM). The biocompatibility assessment was conducted using both in vivo and in vitro experiments, establishing an animal model featuring tibial defects in rats and on the L929 cell line, respectively. The control group, bovine DBM (bDBM), was compared to the S-DBM-treated tibial defect rats. Imaging and histology were used to study implant material changes, defect healing, osteoinductive repair, and degradation.
Results: The findings of our study indicate that S-DBM exhibits favorable repairing effects on bone defects, along with desirable physicochemical characteristics, safety, and osteogenic activity.
Conclusions: The S-DBM holds significant potential as a medical biomaterial for treating bone defects, effectively fulfilling the clinical demands for materials used in bone tissue repair engineering.
{"title":"Application of decalcified bone matrix in Salmon bone for tibial defect repair in rat model.","authors":"Tong Wu, Lei Han, Ye Zhu, Xiaojun Zeng, Yating Kang, Shuwen Zheng, Zhenhai Wang, Jianping Wang, Yonglin Gao","doi":"10.1177/03913988241269498","DOIUrl":"https://doi.org/10.1177/03913988241269498","url":null,"abstract":"<p><strong>Aim: </strong>The optimal preparation conditions of Salmon decalcified bone matrix (S-DBM) were explored, and the properties of S-DBM bone particles and bone powder were studied respectively. The therapeutic effect of S-DBM on tibial defect in female Sprague Dawley (SD) rats was preliminarily verified.</p><p><strong>Methods: </strong>This study assessed the structural and functional similarities of Salmon bone DBM (S-DBM). The biocompatibility assessment was conducted using both in vivo and in vitro experiments, establishing an animal model featuring tibial defects in rats and on the L929 cell line, respectively. The control group, bovine DBM (bDBM), was compared to the S-DBM-treated tibial defect rats. Imaging and histology were used to study implant material changes, defect healing, osteoinductive repair, and degradation.</p><p><strong>Results: </strong>The findings of our study indicate that S-DBM exhibits favorable repairing effects on bone defects, along with desirable physicochemical characteristics, safety, and osteogenic activity.</p><p><strong>Conclusions: </strong>The S-DBM holds significant potential as a medical biomaterial for treating bone defects, effectively fulfilling the clinical demands for materials used in bone tissue repair engineering.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142017343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-21DOI: 10.1177/03913988241268000
Isabell Esslinger, Michael Lommel, Florian Kießlich, Ulrich Kertzscher, Tim Bierewirtz
Thromboembolic complications still arise on blood contacting surfaces. Surface charge and topography influence the subsequent deposition of proteins and platelets, potentially leading to thrombi. Research showed a correlation of surface charge and nanoscale roughness, and a negative surface charge as well as a smooth surface finish are associated with lower thrombogenicity. The aim of this study was to compare the platelet adhesion on titanium with different nanoscale roughnesses and to examine if those roughness variations caused a change in surface charge. Titanium samples were polished and roughened to four different nanoscale roughness levels. Platelet adhesion (covered surface area (CSA), N = 8) was tested in flow chambers with human whole blood using fluorescence imaging. ζ-potential was measured over a broad range of pH-values and interpolated to obtain the ζ-potential for pHBlood (7.4). Platelet adhesion tests were evaluated in terms of p-values and the Wilcoxon test effect size and the trend of the ζ-potential at pHBlood and the CSA was compared. Ra-values ranged between 35 (polished) and 156 nm. Regarding platelet adhesion, the polished sample showed the lowest mean CSA with a medium or strong effect size compared to the roughened samples. The interpolated ζ-potentials for pHBlood follow a similar trend as the CSA, with the lowest ζ-potential measured for the polished surface. These findings suggest that the decreasing ζ-potential due to lower nanoscale roughness might be an additional explanation for the improved hemocompatibility besides the smoother topography.
{"title":"Influence of titanium surface roughness on a nanoscale on the zeta potential and platelet adhesion.","authors":"Isabell Esslinger, Michael Lommel, Florian Kießlich, Ulrich Kertzscher, Tim Bierewirtz","doi":"10.1177/03913988241268000","DOIUrl":"https://doi.org/10.1177/03913988241268000","url":null,"abstract":"<p><p>Thromboembolic complications still arise on blood contacting surfaces. Surface charge and topography influence the subsequent deposition of proteins and platelets, potentially leading to thrombi. Research showed a correlation of surface charge and nanoscale roughness, and a negative surface charge as well as a smooth surface finish are associated with lower thrombogenicity. The aim of this study was to compare the platelet adhesion on titanium with different nanoscale roughnesses and to examine if those roughness variations caused a change in surface charge. Titanium samples were polished and roughened to four different nanoscale roughness levels. Platelet adhesion (covered surface area (CSA), <i>N</i> = 8) was tested in flow chambers with human whole blood using fluorescence imaging. ζ-potential was measured over a broad range of pH-values and interpolated to obtain the ζ-potential for pH<sub>Blood</sub> (7.4). Platelet adhesion tests were evaluated in terms of <i>p</i>-values and the Wilcoxon test effect size and the trend of the ζ-potential at pH<sub>Blood</sub> and the CSA was compared. <i>R</i><sub>a</sub>-values ranged between 35 (polished) and 156 nm. Regarding platelet adhesion, the polished sample showed the lowest mean CSA with a medium or strong effect size compared to the roughened samples. The interpolated ζ-potentials for pH<sub>Blood</sub> follow a similar trend as the CSA, with the lowest ζ-potential measured for the polished surface. These findings suggest that the decreasing ζ-potential due to lower nanoscale roughness might be an additional explanation for the improved hemocompatibility besides the smoother topography.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142017365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-21DOI: 10.1177/03913988241268105
Elena Carrara, Luca Soliveri, Sofia Poloni, Michela Bozzetto, Chiara Emma Campiglio
Mechanical forces related to blood pressure and flow patterns play a crucial role in vascular homeostasis. Perturbations in vascular stresses and strain resulting from changes in hemodynamic may occur in pathological conditions, leading to vascular dysfunction as well as in vascular prosthesis, arteriovenous shunt for hemodialysis and in mechanical circulation support. Turbulent-like blood flows can induce high-frequency vibrations of the vessel wall, and this stimulus has recently gained attention as potential contributors to vascular pathologies, such as development of intimal hyperplasia in arteriovenous fistula for hemodialysis. However, the biological response of vascular cells to this stimulus remains incompletely understood. This review provides an analysis of the existing literature concerning the impact of high-frequency stimuli on vascular cell morphology, function, and gene expression. Morphological and functional investigations reveal that vascular cells stimulated at frequencies higher than the normal heart rate exhibit alterations in cell shape, alignment, and proliferation, potentially leading to vessel remodeling. Furthermore, vibrations modulate endothelial and smooth muscle cells gene expression, affecting pathways related to inflammation, oxidative stress, and muscle hypertrophy. Understanding the effects of high-frequency vibrations on vascular cells is essential for unraveling the mechanisms underlying vascular diseases and identifying potential therapeutic targets. Nevertheless, there are still gaps in our understanding of the molecular pathways governing these cellular responses. Further research is necessary to elucidate these mechanisms and their therapeutic implications for vascular diseases.
{"title":"Effects of high-frequency mechanical stimuli on flow related vascular cell biology.","authors":"Elena Carrara, Luca Soliveri, Sofia Poloni, Michela Bozzetto, Chiara Emma Campiglio","doi":"10.1177/03913988241268105","DOIUrl":"https://doi.org/10.1177/03913988241268105","url":null,"abstract":"<p><p>Mechanical forces related to blood pressure and flow patterns play a crucial role in vascular homeostasis. Perturbations in vascular stresses and strain resulting from changes in hemodynamic may occur in pathological conditions, leading to vascular dysfunction as well as in vascular prosthesis, arteriovenous shunt for hemodialysis and in mechanical circulation support. Turbulent-like blood flows can induce high-frequency vibrations of the vessel wall, and this stimulus has recently gained attention as potential contributors to vascular pathologies, such as development of intimal hyperplasia in arteriovenous fistula for hemodialysis. However, the biological response of vascular cells to this stimulus remains incompletely understood. This review provides an analysis of the existing literature concerning the impact of high-frequency stimuli on vascular cell morphology, function, and gene expression. Morphological and functional investigations reveal that vascular cells stimulated at frequencies higher than the normal heart rate exhibit alterations in cell shape, alignment, and proliferation, potentially leading to vessel remodeling. Furthermore, vibrations modulate endothelial and smooth muscle cells gene expression, affecting pathways related to inflammation, oxidative stress, and muscle hypertrophy. Understanding the effects of high-frequency vibrations on vascular cells is essential for unraveling the mechanisms underlying vascular diseases and identifying potential therapeutic targets. Nevertheless, there are still gaps in our understanding of the molecular pathways governing these cellular responses. Further research is necessary to elucidate these mechanisms and their therapeutic implications for vascular diseases.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142017364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-21DOI: 10.1177/03913988241269444
Sabrina Haroon, Andrew Davenport
Introduction: Intra-dialytic hypotension (IDH) remains the commonest problem associated with routine haemodialysis treatments. Fluid shifts from intracellular(ICW) and extracellular(ECW) compartments to refill plasma volume during haemodialysis with ultrafiltration.
Methods: We studied the effect of relative changes in ICW and ECW indifferent body segments using multifrequency segmental bioimpedance during haemodialysis and IDH episodes.
Results: Of 42 haemodialysis patients,16 patients (38.1%) developed IDH within the first hour of dialysis. Patients with and without early IDH were well-matched for demographics and starting bioimpedance measurements. However, after 60 min, the relative change in in ECW/ICW ratio between the non-fistula arm and leg was significantly different for the early IDH group median -1.07 (-3.33 to 0.8) versus 0.61 (-0.78 to 1.8), p < 0.05, whereas there no differences in ultrafiltration rate, relative blood volume monitoring or on-line clearance.
Conclusion: Monitoring serial changes in fluid status in different body compartments with bioimpedance may potentially prevent IDH in the future.
{"title":"The effect of changes in intra-compartmental bioimpedance measurements with early intra-dialytic hypotension during haemodialysis.","authors":"Sabrina Haroon, Andrew Davenport","doi":"10.1177/03913988241269444","DOIUrl":"https://doi.org/10.1177/03913988241269444","url":null,"abstract":"<p><strong>Introduction: </strong>Intra-dialytic hypotension (IDH) remains the commonest problem associated with routine haemodialysis treatments. Fluid shifts from intracellular(ICW) and extracellular(ECW) compartments to refill plasma volume during haemodialysis with ultrafiltration.</p><p><strong>Methods: </strong>We studied the effect of relative changes in ICW and ECW indifferent body segments using multifrequency segmental bioimpedance during haemodialysis and IDH episodes.</p><p><strong>Results: </strong>Of 42 haemodialysis patients,16 patients (38.1%) developed IDH within the first hour of dialysis. Patients with and without early IDH were well-matched for demographics and starting bioimpedance measurements. However, after 60 min, the relative change in in ECW/ICW ratio between the non-fistula arm and leg was significantly different for the early IDH group median -1.07 (-3.33 to 0.8) versus 0.61 (-0.78 to 1.8), <i>p</i> < 0.05, whereas there no differences in ultrafiltration rate, relative blood volume monitoring or on-line clearance.</p><p><strong>Conclusion: </strong>Monitoring serial changes in fluid status in different body compartments with bioimpedance may potentially prevent IDH in the future.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142008770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-21DOI: 10.1177/03913988241268033
Nicolas Rivoallan, Marc Mueller, Timothée Baudequin, Pascale Vigneron, Anne Hébraud, Rachid Jellali, Quentin Dermigny, Anne Le Goff, Guy Schlatter, Birgit Glasmacher, Cécile Legallais
Thick honeycomb-like electrospun scaffold with nanoparticles of hydroxyapatite (nHA) recently demonstrated its potential to promote proliferation and differentiation of a murine embryonic cell line (C3H10T1/2) to osteoblasts. In order to distinguish the respective effects of the structure and the composition on cell differentiation, beads-on-string fibers were used to manufacture thick honeycomb-like scaffolds without nHA. Mechanical and biological impacts of those beads-on string fibers were evaluated. Uniaxial tensile test showed that beads-on-string fibers decreased the Young Modulus and maximal stress but kept them appropriate for tissue engineering. C3H10T1/2 were seeded and cultured for 6 days on the scaffolds without any growth factors. Viability assays revealed the biocompatibility of the beads-on-string scaffolds, with adequate cells-materials interactions observed by confocal microscopy. Alkaline phosphatase staining was performed at day 6 in order to compare the early differentiation of cells to bone fate. The measure of stained area and intensity confirmed the beneficial effect of both honeycomb structure and nHA, independently. Finally, we showed that honeycomb-like electrospun scaffolds could be relevant candidates for promoting bone fate to cells in the absence of nHA. It offers an easier and faster manufacture process, in particular in bone-interface tissue engineering, permitting to avoid the dispersion of nHA and their interaction with the other cells.
{"title":"Comparison of hydroxyapatite and honeycomb micro-structure in bone tissue engineering using electrospun beads-on-string fibers.","authors":"Nicolas Rivoallan, Marc Mueller, Timothée Baudequin, Pascale Vigneron, Anne Hébraud, Rachid Jellali, Quentin Dermigny, Anne Le Goff, Guy Schlatter, Birgit Glasmacher, Cécile Legallais","doi":"10.1177/03913988241268033","DOIUrl":"https://doi.org/10.1177/03913988241268033","url":null,"abstract":"<p><p>Thick honeycomb-like electrospun scaffold with nanoparticles of hydroxyapatite (nHA) recently demonstrated its potential to promote proliferation and differentiation of a murine embryonic cell line (C3H10T1/2) to osteoblasts. In order to distinguish the respective effects of the structure and the composition on cell differentiation, beads-on-string fibers were used to manufacture thick honeycomb-like scaffolds without nHA. Mechanical and biological impacts of those beads-on string fibers were evaluated. Uniaxial tensile test showed that beads-on-string fibers decreased the Young Modulus and maximal stress but kept them appropriate for tissue engineering. C3H10T1/2 were seeded and cultured for 6 days on the scaffolds without any growth factors. Viability assays revealed the biocompatibility of the beads-on-string scaffolds, with adequate cells-materials interactions observed by confocal microscopy. Alkaline phosphatase staining was performed at day 6 in order to compare the early differentiation of cells to bone fate. The measure of stained area and intensity confirmed the beneficial effect of both honeycomb structure and nHA, independently. Finally, we showed that honeycomb-like electrospun scaffolds could be relevant candidates for promoting bone fate to cells in the absence of nHA. It offers an easier and faster manufacture process, in particular in bone-interface tissue engineering, permitting to avoid the dispersion of nHA and their interaction with the other cells.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142008769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-16DOI: 10.1177/03913988241268026
John K Leypoldt, Mauro Pietribiasi, Malgorzata Debowska, Monika Wieliczko, Malgorzata Twardowska-Kawalec, Jolanta Malyszko, Jacek Waniewski
Introduction: The hydrogen ion (H+) mobilization model has been previously shown to provide a quantitative description of intradialytic changes in blood bicarbonate (HCO3) concentration during hemodialysis (HD). The current study evaluated the accuracy of different methods for estimating the H+ mobilization parameter (Hm) from this model.
Methods: The study compared estimates of the H+ mobilization parameter using predialysis, hourly during the HD treatment, and postdialysis blood HCO3 concentrations (Hm-full2) with those determined using only predialysis and postdialysis blood HCO3 concentrations assuming steady state conditions (Hm-SS2) during the midweek treatment in 24 chronic HD patients treated thrice weekly.
Results: Estimated Hm-full2 values (0.163 ± 0.079 L/min [mean ± standard deviation]) were higher than, but not statistically different (p = 0.067) from, those of Hm-SS2 (0.152 ± 0.065 L/min); the values of Hm-full2 and Hm-SS2 were highly correlated with a correlation coefficient of 0.948 and a mean difference that was small (0.011 L/min). Further, the H+ mobilization parameter values calculated using only predialysis and postdialysis blood HCO3 concentrations during the first and third HD treatments of the week were not different from those calculated during the midweek treatment.
Conclusions: The H+ mobilization model can be used to provide estimates of the H+ mobilization parameter without the need to measure hourly intradialytic blood HCO3 concentrations.
{"title":"Evaluating hydrogen ion mobilization during hemodialysis using only predialysis and postdialysis blood bicarbonate concentrations.","authors":"John K Leypoldt, Mauro Pietribiasi, Malgorzata Debowska, Monika Wieliczko, Malgorzata Twardowska-Kawalec, Jolanta Malyszko, Jacek Waniewski","doi":"10.1177/03913988241268026","DOIUrl":"https://doi.org/10.1177/03913988241268026","url":null,"abstract":"<p><strong>Introduction: </strong>The hydrogen ion (H<sup>+</sup>) mobilization model has been previously shown to provide a quantitative description of intradialytic changes in blood bicarbonate (HCO<sub>3</sub>) concentration during hemodialysis (HD). The current study evaluated the accuracy of different methods for estimating the H<sup>+</sup> mobilization parameter (H<sub>m</sub>) from this model.</p><p><strong>Methods: </strong>The study compared estimates of the H<sup>+</sup> mobilization parameter using predialysis, hourly during the HD treatment, and postdialysis blood HCO<sub>3</sub> concentrations (H<sub>m</sub>-full2) with those determined using only predialysis and postdialysis blood HCO<sub>3</sub> concentrations assuming steady state conditions (H<sub>m</sub>-SS2) during the midweek treatment in 24 chronic HD patients treated thrice weekly.</p><p><strong>Results: </strong>Estimated H<sub>m</sub>-full2 values (0.163 ± 0.079 L/min [mean ± standard deviation]) were higher than, but not statistically different (<i>p</i> = 0.067) from, those of H<sub>m</sub>-SS2 (0.152 ± 0.065 L/min); the values of H<sub>m</sub>-full2 and H<sub>m</sub>-SS2 were highly correlated with a correlation coefficient of 0.948 and a mean difference that was small (0.011 L/min). Further, the H<sup>+</sup> mobilization parameter values calculated using only predialysis and postdialysis blood HCO<sub>3</sub> concentrations during the first and third HD treatments of the week were not different from those calculated during the midweek treatment.</p><p><strong>Conclusions: </strong>The H<sup>+</sup> mobilization model can be used to provide estimates of the H<sup>+</sup> mobilization parameter without the need to measure hourly intradialytic blood HCO<sub>3</sub> concentrations.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141987865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Previously, we found analytic solutions for single ventricular system based on the lumped parameter model (LPM). In this study, we generalized the method to biventricular system and derived its analytic solutions. LPM is just a set of differential equations, but it is difficult to solve due to time-varying ventricular elastance and high order. Mathematically, there exist no elementary solutions for time-varying equations. It turns out that instead of differential equations, according to volume conservation, a set of algebraic equations can be carried out. The solutions of the set of equations are just physiological states at end of systolic and diastolic phases such as end systolic/diastolic pressure/volume of left ventricle. As a preliminary application, the method is utilized to deduce the hemodynamic effects of VA ECMO. Left ventricular (LV) distension, a serious complication of VA ECMO, is usually attributed to factors such as increased afterload, inadequate LV unloading, reduced myocardial contractility or aortic valve regurgitation (AR), bronchial and Thebesian return in the absence of aortic valve (AoV) opening. Among these, reduced contractility and AR are strongly associated with LV distension. However, in the absence of reduced contractility or AR, it is less clear whether increased afterload or inadequate LV unloading alone can cause LV distension. This leads to the critical question: under what conditions does LV distension occur in the absence of reduced contractility or AR? The analytic formulas derived in this study give conditions for LV distension. Furthermore, the results show that the analytic hemodynamics are coincident with simulated results.
在此之前,我们基于块参数模型(LPM)找到了单心室系统的解析解。在这项研究中,我们将该方法推广到了双心室系统,并得出了其解析解。LPM 只是一组微分方程,但由于心室弹性时变且阶数较高,因此很难求解。在数学上,不存在时变方程的基本解。原来,根据体积守恒,可以用一组代数方程来代替微分方程。方程组的解只是收缩期和舒张期结束时的生理状态,如收缩末期/舒张末期压力/左心室容积。作为初步应用,该方法用于推断 VA ECMO 的血液动力学效应。左心室(LV)胀大是 VA ECMO 的一种严重并发症,通常归因于后负荷增加、左心室卸载不足、心肌收缩力降低或主动脉瓣反流(AR)、主动脉瓣(AoV)未开放时支气管和忒拜斯回流等因素。其中,心肌收缩力减弱和主动脉瓣反流与左心室扩张密切相关。然而,在没有收缩力降低或 AR 的情况下,后负荷增加或 LV 负荷不足是否会单独导致 LV 舒张还不太清楚。这就引出了一个关键问题:在没有收缩力减弱或 AR 的情况下,左心室扩张会在什么条件下发生?本研究得出的分析公式给出了左心室扩张的条件。此外,结果表明分析血流动力学与模拟结果相吻合。
{"title":"An analytic method to investigate hemodynamics of the cardiovascular system: Biventricular system.","authors":"Yuxin Zhu, Xu Mei, Wanning Ge, Tingting Wu, Liudi Zhang, Polin Hsu","doi":"10.1177/03913988241260943","DOIUrl":"https://doi.org/10.1177/03913988241260943","url":null,"abstract":"<p><p>Previously, we found analytic solutions for single ventricular system based on the lumped parameter model (LPM). In this study, we generalized the method to biventricular system and derived its analytic solutions. LPM is just a set of differential equations, but it is difficult to solve due to time-varying ventricular elastance and high order. Mathematically, there exist no elementary solutions for time-varying equations. It turns out that instead of differential equations, according to volume conservation, a set of algebraic equations can be carried out. The solutions of the set of equations are just physiological states at end of systolic and diastolic phases such as end systolic/diastolic pressure/volume of left ventricle. As a preliminary application, the method is utilized to deduce the hemodynamic effects of VA ECMO. Left ventricular (LV) distension, a serious complication of VA ECMO, is usually attributed to factors such as increased afterload, inadequate LV unloading, reduced myocardial contractility or aortic valve regurgitation (AR), bronchial and Thebesian return in the absence of aortic valve (AoV) opening. Among these, reduced contractility and AR are strongly associated with LV distension. However, in the absence of reduced contractility or AR, it is less clear whether increased afterload or inadequate LV unloading alone can cause LV distension. This leads to the critical question: under what conditions does LV distension occur in the absence of reduced contractility or AR? The analytic formulas derived in this study give conditions for LV distension. Furthermore, the results show that the analytic hemodynamics are coincident with simulated results.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141901691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-08DOI: 10.1177/03913988241266088
Ana M Muñoz-Gonzalez, Sara Leal-Marin, Dianney Clavijo-Grimaldo, Birgit Glasmacher
Cardiovascular diseases, particularly myocardial infarction, have significant healthcare challenges due to the limited regenerative capacity of injured heart tissue. Cardiac tissue engineering (CTE) offers a promising approach to repairing myocardial damage using biomaterials that mimic the heart's extracellular matrix. This study investigates the potential of graphene nanopowder (Gnp)-enhanced polycaprolactone (PCL) scaffolds fabricated via electrospinning to improve the properties necessary for effective cardiac repair. This work aimed to analyze scaffolds with varying graphene concentrations (0.5%, 1%, 1.5%, and 2% by weight) to determine their morphological, chemical, mechanical, and biocompatibility characteristics. The results presented that incorporating graphene improves PCL scaffolds' mechanical properties and cellular interactions. The optimal concentration of 1% graphene significantly enhanced mechanical properties and biocompatibility, promoting cell adhesion and proliferation. These findings suggest that Gnp-enhanced PCL scaffolds at this concentration can serve as a potent substrate for CTE providing insights into designing more effective biomaterials for myocardial restoration.
{"title":"Graphene-enhanced PCL electrospun nanofiber scaffolds for cardiac tissue engineering.","authors":"Ana M Muñoz-Gonzalez, Sara Leal-Marin, Dianney Clavijo-Grimaldo, Birgit Glasmacher","doi":"10.1177/03913988241266088","DOIUrl":"https://doi.org/10.1177/03913988241266088","url":null,"abstract":"<p><p>Cardiovascular diseases, particularly myocardial infarction, have significant healthcare challenges due to the limited regenerative capacity of injured heart tissue. Cardiac tissue engineering (CTE) offers a promising approach to repairing myocardial damage using biomaterials that mimic the heart's extracellular matrix. This study investigates the potential of graphene nanopowder (Gnp)-enhanced polycaprolactone (PCL) scaffolds fabricated via electrospinning to improve the properties necessary for effective cardiac repair. This work aimed to analyze scaffolds with varying graphene concentrations (0.5%, 1%, 1.5%, and 2% by weight) to determine their morphological, chemical, mechanical, and biocompatibility characteristics. The results presented that incorporating graphene improves PCL scaffolds' mechanical properties and cellular interactions. The optimal concentration of 1% graphene significantly enhanced mechanical properties and biocompatibility, promoting cell adhesion and proliferation. These findings suggest that Gnp-enhanced PCL scaffolds at this concentration can serve as a potent substrate for CTE providing insights into designing more effective biomaterials for myocardial restoration.</p>","PeriodicalId":13932,"journal":{"name":"International Journal of Artificial Organs","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141901692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}