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Hanna Radecka - One of the best experts on this subject based on the ideXlab platform.
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Electrochemical Biosensor for the Detection of Glycated Albumin.
Current Alzheimer research, 2017Co-Authors: Edyta Mikuła, Peter Verwilst, Wim Dehaen, Jerzy Radecki, Aleksandra Wysłouch-cieszyńska, Liliya Zhukova, Hanna RadeckaAbstract:Background: Alzheimer’s disease (AD) is the most common form of dementia. The process of AD can begin 20 years before any symptom of cognitive loss. Thus, the development of systems for early diagnosis and prevention is very important. The mechanism of AD is still under debate. Nevertheless, higher levels of glycated albumin in cerebrospinal fluid and plasma are observed in AD patients. Therefore, glycated albumin could be a biomarker of AD development. Methods: Electrochemical biosensor for direct determination of glycated albumin was based on Thiol Derivative of pentetic acid (DTPA) complex with Cu(II) created on gold electrode surface. His-tagged domains of Receptors for Advanced Glycation End Products (RAGE) were applied as analytical active element for glycated albumin recognition. The binding of glycated albumin by His6- RAGE domains was monitored using Osteryoung square - wave voltammetry. Results: Electrodes modified with His6 - RAGE VC1 natural domain generated decrease of Cu(II) redox currents in the presence of glycated albumin. Human albumin, Aβ 1-40 and S100B protein caused negligible influence on biosensors responses towards glycated albumin. The detection limits were: 2.3 pM, 1.1 pM, 2.9 pM and 3.1 pM in the presence of: buffer, buffer + albumin, buffer + S100B, buffer + Aβ1-40 , respectively. Conclusion: The presented electrochemical biosensor was successfully applied for the determination of glycated albumin. Considering analytical parameters such as good selectivity and sensitivity in pM range, biosensor could be recommended as an analytical tool for medical samples analysis.
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Voltammetric Detection of S100B Protein Using His-Tagged Receptor Domains for Advanced Glycation End Products (RAGE) Immobilized onto a Gold Electrode Surface
Sensors, 2014Co-Authors: Edyta Mikuła, Peter Verwilst, Wim Dehaen, Jerzy Radecki, Aleksandra Wysłouch-cieszyńska, Liliya Zhukova, M. Puchalska, Hanna RadeckaAbstract:In this work we report on an electrochemical biosensor for the determination of the S100B protein. The His-tagged VC1 domains of Receptors for Advanced Glycation End (RAGE) products used as analytically active molecules were covalently immobilized on a monolayer of a Thiol Derivative of pentetic acid (DPTA) complex with Cu(II) deposited on a gold electrode surface. The recognition processes between the RAGE VC1 domain and the S100B protein results in changes in the redox activity of the DPTA-Cu(II) centres which were measured by Osteryoung square-wave voltammetry (OSWV). In order to verify whether the observed analytical signal originates from the recognition process between the His6–RAGE VC1 domains and the S100B protein, the electrode modified with the His6–RAGE C2 and His6–RAGE VC1 deleted domains which have no ability to bind S100B peptides were applied. The proposed biosensor was quite sensitive, with a detection limit of 0.52 pM recorded in the buffer solution. The presence of diluted human plasma and 10 nM Aβ1-40 have no influence on the biosensor performance.
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Immobilization of His-tagged kinase JAK2 onto the surface of a plasmon resonance gold disc modified with different copper (II) complexes.
Talanta, 2014Co-Authors: Katarzyna Kurzątkowska, Marcin Mielecki, Krystyna Grzelak, Peter Verwilst, Wim Dehaen, Jerzy Radecki, Hanna RadeckaAbstract:New surface plasmon resonance (SPR) sensing platforms which consists of copper (II) complexes of a pentetic acid Thiol ligand (DPTA-Cu(II)) and of a Thiol Derivative of dipyrromethene (DPM-Cu(II) created on the surface of gold SPR disc were applied to oriented immobilization of His-tagged Janus kinase 2 (GST-His6-JAK2). This method is based on the covalent bond formation between histidine from a His-tag chain of a protein and Cu(II) centres from the complexes. The kinetic and thermodynamic parameters of the oriented immobilization of GST-His6-JAK2 protein to DPTA-Cu(II) and DPM-Cu(II) complexes attached to the Au surface of a SPR disc were discussed.
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oriented immobilization of his tagged protein on a redox active Thiol Derivative of dpta cu ii layer deposited on a gold electrode the base of electrochemical biosensors
Sensors, 2013Co-Authors: Edyta Mikula, Peter Verwilst, Wim Dehaen, Jerzy Radecki, Magdalena Sulima, Ilona Marszalek, Aleksandra Wyslouchcieszynska, Hanna RadeckaAbstract:This paper concerns the development of an electrochemical biosensor for the determination of Aβ16–23' and Aβ1–40 peptides. The His-tagged V and VC1 domains of Receptor for Advanced Glycation end Products (RAGE) immobilized on a gold electrode surface were used as analytically active molecules. The immobilization of His6–RAGE domains consists of: (i) formation of a mixed layer of N-acetylcysteamine (NAC) and the Thiol Derivative of pentetic acid (DPTA); (ii) complexation of Cu(II) by DPTA; (iii) oriented immobilization of His6–RAGE domains via coordination bonds between Cu(II) sites from DPTA–Cu(II) complex and imidazole nitrogen atoms of a histidine tag. Each modification step was controlled by cyclic voltammetry (CV), Osteryoung square-wave voltammetry (OSWV), and atomic force microscopy (AFM). The applicability of the proposed biosensor was tested in the presence of human plasma, which had no influence on its performance. The detection limits for Aβ1–40 determination were 1.06 nM and 0.80 nM, in the presence of buffer and human plasma, respectively. These values reach the concentration level of Aβ1–40 which is relevant for determination of its soluble form in human plasma, as well as in brain. This indicates the promising future application of biosensor presented for early diagnosis of neurodegenerative diseases.
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Oriented Immobilization of His-Tagged Protein on a Redox Active Thiol Derivative of DPTA-Cu(II) Layer Deposited on a Gold Electrode—The Base of Electrochemical Biosensors
Sensors, 2013Co-Authors: Edyta Mikuła, Peter Verwilst, Wim Dehaen, Jerzy Radecki, Aleksandra Wysłouch-cieszyńska, Magdalena Sulima, Ilona Marszałek, Hanna RadeckaAbstract:This paper concerns the development of an electrochemical biosensor for the determination of Aβ16–23' and Aβ1–40 peptides. The His-tagged V and VC1 domains of Receptor for Advanced Glycation end Products (RAGE) immobilized on a gold electrode surface were used as analytically active molecules. The immobilization of His6–RAGE domains consists of: (i) formation of a mixed layer of N-acetylcysteamine (NAC) and the Thiol Derivative of pentetic acid (DPTA); (ii) complexation of Cu(II) by DPTA; (iii) oriented immobilization of His6–RAGE domains via coordination bonds between Cu(II) sites from DPTA–Cu(II) complex and imidazole nitrogen atoms of a histidine tag. Each modification step was controlled by cyclic voltammetry (CV), Osteryoung square-wave voltammetry (OSWV), and atomic force microscopy (AFM). The applicability of the proposed biosensor was tested in the presence of human plasma, which had no influence on its performance. The detection limits for Aβ1–40 determination were 1.06 nM and 0.80 nM, in the presence of buffer and human plasma, respectively. These values reach the concentration level of Aβ1–40 which is relevant for determination of its soluble form in human plasma, as well as in brain. This indicates the promising future application of biosensor presented for early diagnosis of neurodegenerative diseases.
Xingchen Peng - One of the best experts on this subject based on the ideXlab platform.
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Antitumor and radiosensitizing effects of SKLB-163, a novel benzothiazole-2-Thiol Derivative, on nasopharyngeal carcinoma by affecting the RhoGDI/JNK-1 signaling pathway.
Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology, 2018Co-Authors: Lei Cai, Ye Chen, Ming Wang, Jie Tang, Hui Guan, Jingjing Wang, Xingchen PengAbstract:Abstract Background and purpose SKLB-163 is a novel benzothiazole-2-Thiol Derivative with antitumor activities. This study investigated the effects of SKLB-163 on nasopharyngeal carcinoma (NPC) and its mechanisms. Materials and methods Rho GDP-dissociation inhibitor (RhoGDI) expression was examined in NPC cell lines by western blot. Effects of SKLB-163 on proliferation, migration and radiosensitivity were assessed by MTT, wound healing and colony formation assays in vitro. Anti-tumor and anti-metastatic effects, and radiosensitizing effects of SKLB-163 were evaluated in a NPC lung metastatic nude mouse model and a subcutaneous xenograft mouse model. Effects of SKLB-163 on proliferation and apoptosis were assessed by PCNA immunohistochemistry and TUNEL assay in vivo. Key molecules in RhoGDI/c-Jun N-terminal kinases-1 (JNK-1) pathway were examined by western blot. Results RhoGDI was up-regulated in NPC cell lines. SKLB-163 inhibited proliferation and migration, and increased radiosensitivity of NPC cells. SKLB-163 inhibited tumor growth and metastases, and sensitized tumor to irradiation. The radiosensitizing effects were correlated with induction of apoptosis and suppression of proliferation. The molecular mechanism was the down-regulation of RhoGDI and activation of JNK-1 signaling, and the subsequent activation of caspase-3 and the decrease in phosphorylated AKT. Conclusions SKLB-163 shows strong anti-tumor activities against NPC and sensitizes NPC to irradiation by affecting the RhoGDI/JNK-1 pathway.
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antitumor and radiosensitizing effects of sklb 163 a novel benzothiazole 2 Thiol Derivative on nasopharyngeal carcinoma by affecting the rhogdi jnk 1 signaling pathway
Radiotherapy and Oncology, 2018Co-Authors: Lei Cai, Ye Chen, Ming Wang, Jie Tang, Hui Guan, Jingjing Wang, Xingchen PengAbstract:Abstract Background and purpose SKLB-163 is a novel benzothiazole-2-Thiol Derivative with antitumor activities. This study investigated the effects of SKLB-163 on nasopharyngeal carcinoma (NPC) and its mechanisms. Materials and methods Rho GDP-dissociation inhibitor (RhoGDI) expression was examined in NPC cell lines by western blot. Effects of SKLB-163 on proliferation, migration and radiosensitivity were assessed by MTT, wound healing and colony formation assays in vitro. Anti-tumor and anti-metastatic effects, and radiosensitizing effects of SKLB-163 were evaluated in a NPC lung metastatic nude mouse model and a subcutaneous xenograft mouse model. Effects of SKLB-163 on proliferation and apoptosis were assessed by PCNA immunohistochemistry and TUNEL assay in vivo. Key molecules in RhoGDI/c-Jun N-terminal kinases-1 (JNK-1) pathway were examined by western blot. Results RhoGDI was up-regulated in NPC cell lines. SKLB-163 inhibited proliferation and migration, and increased radiosensitivity of NPC cells. SKLB-163 inhibited tumor growth and metastases, and sensitized tumor to irradiation. The radiosensitizing effects were correlated with induction of apoptosis and suppression of proliferation. The molecular mechanism was the down-regulation of RhoGDI and activation of JNK-1 signaling, and the subsequent activation of caspase-3 and the decrease in phosphorylated AKT. Conclusions SKLB-163 shows strong anti-tumor activities against NPC and sensitizes NPC to irradiation by affecting the RhoGDI/JNK-1 pathway.
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sklb 163 a new benzothiazole 2 Thiol Derivative exhibits potent anticancer activity by affecting rhogdi jnk 1 signaling pathway
Cell Death and Disease, 2017Co-Authors: Xingchen Peng, Gang Xie, Zhao Wang, Hong-hui Lin, Tian Zhou, Pu Xiang, Yuchen Jiang, Shuping Yang, Yuyan Wei, Yunuo ZhaoAbstract:Small-molecule inhibitors are an attractive therapeutic approach for most types of human cancers. SKLB-163, a novel benzothiazole-2-Thiol Derivative, was developed via computer-aided drug design and de novo synthesis. MTT assay showed it had potent anti-proliferative activity on various human cancer cells. Treatment of cancer cells with SKLB-163 induced obvious apoptosis and inhibited proliferation in vitro. SKLB-163 administered p.o. showed a marked antitumor activity in vivo. Proteomic techniques were employed to identify possible drug target proteins. The data showed molecular mechanism of action might be involved in downregulation of RhoGDI, which finally contributed to increased apoptosis and inhibited proliferation. These findings provided the potential value of SKLB-163 as a novel candidate antitumor drug.
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Antitumor and antimetastatic activities of a novel benzothiazole-2-Thiol Derivative in a murine model of breast cancer
Oncotarget, 2017Co-Authors: Lei Cai, Xingchen PengAbstract:// XiaoLin Hu 1, * , Sen Li 2, * , Yan He 3, * , Ping Ai 3, * , Shaoyong Wu 3, * , Yonglin Su 4, * , Xiaolin Li 5 , Lei Cai 6 , Xingchen Peng 3 1 Department of Nursing, West China Hospital, Sichuan University, Chengdu, China 2 Department of Spinal Surgery, Traditional Chinese Medicine Hospital of SouthWest Medical University, Luzhou, China 3 Department of Medical Oncology, Cancer Center, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China 4 Department of Rehabilitation, West China Hospital, Sichuan University, Chengdu, China 5 Department of Pathophysiology, Basic Medical College, Jilin University, Changchun, China 6 Hepatobiliary Surgery Institute, Southwest Hospital, Third Military Medical University, Chongqing, China * These authors have contributed equally to this work Correspondence to: Xingchen Peng, email: pxx2014@sohu.com Keywords: benzothiazole-2-Thiol Derivative, breast cancer, proliferation, metastasis, apoptosis Received: November 24, 2016 Accepted: December 21, 2016 Published: January 02, 2017 ABSTRACT The prognosis of metastatic breast cancer is always very poor. Thus, it is urgent to develop novel drugs with less toxicity against metastatic breast cancer. A new drug (XC-591) derived from benzothiazole-2-Thiol was designed and synthesized in our lab. In this study, we tried to assess effects of XC-591 treatment on primary breast cancer and pulmonary metastasis in 4T1 mice model. Furthermore, we tried to discover its possible molecular mechanism of action. MTT experiment showed XC-591 had significant anti-cancer activity on diverse cancer cells. Furthermore, XC-591 significantly suppressed the proliferation of 4T1 cells by colony formation assay. The in vivo results displayed that XC-591 could inhibit the growth and metastasis in 4T1 model. Moreover, histological analysis revealed that XC-591 treatment increased apoptosis, inhibited proliferation and angiogenesis in vivo . In addition, XC-591 did not contribute to obvious drug associated toxicity during the whole study. Molecular mechanism showed XC-591 could inhibit RhoGDI, activate caspase-3 and decrease phosphorylated Akt. The present data may be important to further explore this kind of new small-molecule inhibitor.
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SKLB-163, a new benzothiazole-2-Thiol Derivative, exhibits potent anticancer activity by affecting RhoGDI/JNK-1 signaling pathway.
Cell death & disease, 2014Co-Authors: Xingchen Peng, Gang Xie, Zhao Wang, Hong-hui Lin, Tian Zhou, Pu Xiang, Yuchen Jiang, Shuping Yang, Yuyan WeiAbstract:Small-molecule inhibitors are an attractive therapeutic approach for most types of human cancers. SKLB-163, a novel benzothiazole-2-Thiol Derivative, was developed via computer-aided drug design and de novo synthesis. MTT assay showed it had potent anti-proliferative activity on various human cancer cells. Treatment of cancer cells with SKLB-163 induced obvious apoptosis and inhibited proliferation in vitro. SKLB-163 administered p.o. showed a marked antitumor activity in vivo. Proteomic techniques were employed to identify possible drug target proteins. The data showed molecular mechanism of action might be involved in downregulation of RhoGDI, which finally contributed to increased apoptosis and inhibited proliferation. These findings provided the potential value of SKLB-163 as a novel candidate antitumor drug.
Sunao Yamada - One of the best experts on this subject based on the ideXlab platform.
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novel photoelectrochemical cell using a self assembled monolayer of a ruthenium ii tris 2 2 bipyridine Thiol Derivative
Japanese Journal of Applied Physics, 2002Co-Authors: Tsuyoshi Akiyama, Masayuki Inoue, Yutaka Kuwahara, Sunao YamadaAbstract:A novel thin-layer two-electrode photoelectrochemical cell consisting of a self-assembled monolayer of a ruthenium (II) tris(2,2'-bipyridine) Thiol Derivative on a transparent indium tin oxide (ITO) electrode and a bare ITO electrode was fabricated, and exhibited satisfactory performance as a photocell. A ruthenium (II) tris(2,2'-bipyridine)-viologen (electron donor–acceptor) pair yielded a higher performance of the photocell than the ruthenium complex (donor) moiety alone. Photoinduced electron transfer from the photoexcited ruthenium complex moiety to the viologen moiety was quite effective for generating larger photocurrents.
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A photoresponsive molecular assembly consisting of ruthenium(II) tris(2,2′-bipyridine)-viologen linked disulfide and hexadecaneThiol prepared on a gold surface: Effect of viologen moiety☆
Journal of Electroanalytical Chemistry, 1997Co-Authors: Sunao Yamada, Yasuhisa Koide, Taku MatsuoAbstract:Abstract A ruthenium tris(2,2′-bipyridine)-viologen linked Thiol Derivative was prepared, and the monolayer assembly of the mixture of this compound and hexadecaneThiol was fabricated on a gold surface. In the presence of triethanolamine, the modified gold electrode with this compound showed clear photocurrent responses ascribed to the ruthenium complex sensitized photoredox cycles with the viologen moiety as the mediator.
Taku Matsuo - One of the best experts on this subject based on the ideXlab platform.
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A photoresponsive molecular assembly consisting of ruthenium(II) tris(2,2′-bipyridine)-viologen linked disulfide and hexadecaneThiol prepared on a gold surface: Effect of viologen moiety☆
Journal of Electroanalytical Chemistry, 1997Co-Authors: Sunao Yamada, Yasuhisa Koide, Taku MatsuoAbstract:Abstract A ruthenium tris(2,2′-bipyridine)-viologen linked Thiol Derivative was prepared, and the monolayer assembly of the mixture of this compound and hexadecaneThiol was fabricated on a gold surface. In the presence of triethanolamine, the modified gold electrode with this compound showed clear photocurrent responses ascribed to the ruthenium complex sensitized photoredox cycles with the viologen moiety as the mediator.
Denis Le Paslier - One of the best experts on this subject based on the ideXlab platform.
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Transformation of the recalcitrant pesticide chlordecone by Desulfovibrio sp.86 with a switch from ring-opening dechlorination to reductive sulfidation activity.
Scientific reports, 2020Co-Authors: Oriane Della-negra, Sébastien Chaussonnerie, Nuria Fonknechten, Agnès Barbance, Delphine Muselet, Déborah E. Martin, Stéphanie Fouteau, Cécile Fischer, Pierre-loïc Saaidi, Denis Le PaslierAbstract:The insecticide chlordecone has been used in the French West Indies for decades, resulting in long term pollution, human health problems and social crisis. In addition to bacterial consortia and Citrobacter sp.86 previously described to transform chlordecone into three families of transformation products (A: hydrochlordecones, B: polychloroindenes and C: polychloroindenecarboxylic acids), another bacterium Desulfovibrio sp.86, showing the same abilities has been isolated and its genome was sequenced. Ring-opening dechlorination, leading to A, B and C families, was observed as previously described. Changing operating conditions in the presence of chlordecone gave rise to the formation of an unknown sulfur-containing transformation product instead of the aforementioned ones. Its structural elucidation enabled to conclude to a Thiol Derivative, which corresponds to an undocumented bacterial reductive sulfidation. Microbial experiments pointed out that the chlordecone Thiol Derivative was observed in anaerobiosis, and required the presence of an electron acceptor containing sulfur or hydrogen sulfide, in a confined atmosphere. It seems that this new reaction is also active on hydrochlordecones, as the 10-monohydrochlordecone A1 was transformed the same way. Moreover, the chlordecone Thiol Derivative called F1 was detected in several chlordecone contaminated mangrove bed sediments from Martinique Island, highlighting the environmental relevance of these results.
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Transformation of the recalcitrant pesticide chlordecone by Desulfovibrio sp.86 with a switch from ring-opening dechlorination to reductive sulfidation activity
Scientific Reports, 2020Co-Authors: Oriane Della-negra, Sébastien Chaussonnerie, Nuria Fonknechten, Agnès Barbance, Delphine Muselet, Stéphanie Fouteau, Cécile Fischer, Pierre-loïc Saaidi, Déborah Martin, Denis Le PaslierAbstract:The insecticide chlordecone has been used in the French West Indies for decades, resulting in long term pollution, human health problems and social crisis. In addition to bacterial consortia and Citrobacter sp.86 previously described to transform chlordecone into three families of transformation products (A: hydrochlordecones, B: polychloroindenes and C: polychloroindenecarboxylic acids), another bacterium Desulfovibrio sp.86, showing the same abilities has been isolated and its genome was sequenced. Ring-opening dechlorination, leading to A, B and C families, was observed as previously described. changing operating conditions in the presence of chlordecone gave rise to the formation of an unknown sulfur-containing transformation product instead of the aforementioned ones. Its structural elucidation enabled to conclude to a Thiol Derivative, which corresponds to an undocumented bacterial reductive sulfidation. Microbial experiments pointed out that the chlordecone Thiol Derivative was observed in anaerobiosis, and required the presence of an electron acceptor containing sulfur or hydrogen sulfide, in a confined atmosphere. It seems that this new reaction is also active on hydrochlordecones, as the 10-monohydrochlordecone A1 was transformed the same way. Moreover, the chlordecone Thiol Derivative called F1 was detected in several chlordecone contaminated mangrove bed sediments from Martinique Island, highlighting the environmental relevance of these results. Chlordecone is a highly recalcitrant organochlorine pesticide that has been added to the Stockholm convention list of persistent organic pollutants in 2009. Several pest control products containing chlordecone (Kepone, Curlone) or a functionalized Derivative (Kelevan) have been manufactured in the US, Brazil and France and applied in the Caribbean, Central America, West Africa, and Europe over an extended period of forty years 1. To date, chlordecone has caused two major environmental disasters: (1) acute exposure of workers at the Hopewell (US) chlordecone production plant in 1975 and massive pollution of the James River, extending over 100 miles that lasted for decades 2 , (2) ongoing impregnation of the French West Indies (FWI) population due to extensive agricultural use of chlordecone from 1972 to 1993 that has resulted in long-term pollution of environmental compartments (soils, water resources, coastal areas) and subsequently of some local food production (vegetables, farmed animals, and seafood). Until now, no remediation strategy has been proven satisfactory in the FWI environment whereas the population has to deal with health troubles (increased risk of cancer, motor and cognitive development disorders in young children, premature births) and social difficulties (disappearance of local economy activities) 1 .