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Genes & Diseases 2024年第3期11卷 136-139页

作者： Yuchao Yang Shutong Wu Rongmei Qu Congrong Wang Jinyang Wang asmat ullah khan You Pan Wenqing Liu Jinhui Zhu Muhammad Akram khan Chujiang Xu Jingxing Dai Jun Ouyang Guangdong Provincial Key Laboratory of Medical Biomechanics&National Key Discipline of Human Anatomy Schoolof BasicMedical SciencesSouthern Medical UniversityGuangzhouGuangdong 510515China Department of Laboratory Medicine Nanfang Hospital of Southern Medical UniversityGuangzhouGuangdong 510515China Department of Pathology Guangdong Provincial People's HospitalGuangdong Academy of Medical SciencesGuangzhouGuangdong 510080China Department of Breast Surgery Guangxi Medical University Cancer HospitalNanningGuangxi 530000China Department of Veterinary Pathology Faculty of Veterinary and Animal SciencesPMAS Arid Agriculture UniversityRawalpindi 46300Pakistan Department of Orthopedics TCM-Integrated HospitalSouthern Medical UniversityGuangzhouGuangdong 510000China

Bone regeneration is a multifaceted,abstract,and wellcoordinated physiological progression of bone formation that participates in continuous regeneration and remodeling throughout life.However,when it comes to complex clinical situations requiring extensive bone regeneration,such as massive bone defects caused by injuries,infection,or tumor removal,traditional methods do not often yield good treatment strategies or protocols due to their limitations.

关键词： alterations injuries massive

Expansion of human umbilical cord derived mesenchymal stem cells in regenerative medicine

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World Journal of Stem Cells 2024年第4期16卷 410-433页

作者： Shafiqa Naeem Rajput Bushra Kiran Naeem Anwar Ali asmat Salim Irfan khan Dr.Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological SciencesUniversity of KarachiKarachi 75270SindhPakistan Surgical Unit 4 Dr.Ruth KM Pfau Civil HospitalKarachi 74400Pakistan Department of Physiology University of KarachiKarachi 75270Pakistan Center for Regenerative Medicine and Stem Cells Research and Department of Ophthalmology and Visual SciencesThe Aga Khan UniversityKarachi 74800SindhPakistan

BACKGROUND Stem cells are undifferentiated cells that possess the potential for self-renewal with the capacity to differentiate into multiple lineages.In humans,their limited numbers pose a challenge in fulfilling the necessary demands for the regeneration and repair of damaged tissues or organs.Studies suggested that mesenchymal stem cells(MSCs),necessary for repair and regeneration via transplantation,require doses ranging from 10 to 400 million cells.Furthermore,the limited expansion of MSCs restricts their therapeutic application.AIM To optimize a novel protocol to achieve qualitative and quantitative expansion of MSCs to reach the targeted number of cells for cellular transplantation and minimize the limitations in stem cell therapy protocols.METHODS Human umbilical cord(hUC)tissue derived MSCs were obtained and re-cultured.These cultured cells were subjected to the following evaluation pro-cedures:Immunophenotyping,immunocytochemical staining,trilineage differentiation,population doubling time and number,gene expression markers for proliferation,cell cycle progression,senescence-associatedβ-galactosidase assay,human telomerase reverse transcriptase(hTERT)expression,mycoplasma,cytomegalovirus and endotoxin detection.RESULTS Analysis of pluripotent gene markers Oct4,Sox2,and Nanog in recultured hUC-MSC revealed no significant differences.The immunophenotypic markers CD90,CD73,CD105,CD44,vimentin,CD29,Stro-1,and Lin28 were positively expressed by these recultured expanded MSCs,and were found negative for CD34,CD11b,CD19,CD45,and HLA-DR.The recultured hUC-MSC population continued to expand through passage 15.Proliferative gene expression of Pax6,BMP2,and TGFb1 showed no significant variation between recultured hUC-MSC groups.Nevertheless,a significant increase(P<0.001)in the mitotic phase of the cell cycle was observed in recultured hUC-MSCs.Cellular senescence markers(hTERT expression andβ-galactosidase activity)did not show any negative effect on recultured hUC-MSCs.Additionally,quality control assessments co

关键词： Human umbilical cord Mesenchymal stem cells Expansion Cell proliferation In vitro expansion Senescence

细胞骨架相关蛋白PDLIM5在人成纤维细胞内的定位及调控作用

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中国临床解剖学杂志 2022年第5期40卷 536-540页

作者：黄小兰彭彦杨宇超樊庭宇孙冰 asmat ullah khan 戴景兴欧阳钧钟世镇南方医科大学基础医学院人体解剖学教研室暨广东省医学生物力学重点实验室广州510515

目的研究细胞骨架相关蛋白PDLIM5在人成纤维细胞内的定位及其调控作用。方法通过慢病毒转染下调PDLIM5在人成纤维细胞中的表达后,进行CCK8细胞增殖实验、细胞划痕实验、Transwell迁移实验来检测PDLIM5对细胞增殖和运动迁移能力的影响,... 详细信息

目的研究细胞骨架相关蛋白PDLIM5在人成纤维细胞内的定位及其调控作用。方法通过慢病毒转染下调PDLIM5在人成纤维细胞中的表达后,进行CCK8细胞增殖实验、细胞划痕实验、Transwell迁移实验来检测PDLIM5对细胞增殖和运动迁移能力的影响,通过免疫荧光染色来观察PDLIM5的亚细胞定位。结果下调PDLIM5表达后抑制了人成纤维细胞的增殖、运动和迁移能力,免疫荧光发现PDLIM5主要表达在细胞质并定位于微丝。结论 PDLIM5定位于细胞骨架微丝,下调PDLIM5表达可抑制人成纤维细胞的增殖、运动和迁移能力。

关键词：人成纤维细胞 PDLIM5 微丝细胞骨架相关蛋白

Transcription regulators differentiate mesenchymal stem cells into chondroprogenitors,and their in vivo implantation regenerated the intervertebral disc degeneration

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World Journal of Stem Cells 2022年第2期14卷 163-182页

作者： Shumaila Khalid Sobia Ekram asmat Salim G.Rasul Chaudhry Irfan khan Dr.Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological SciencesUniversity of KarachiKarachi 75270SindhPakistan Department of Biological Sciences Oakland UniversityRochesterMI 48309United States

BACKGROUND Intervertebral disc degeneration(IVDD)is the leading cause of lower back pain.Disc degeneration is characterized by reduced cellularity and decreased production of extracellular matrix(ECM).Mesenchymal stem cells(MSCs)have been envisioned as a promising treatment for degenerative illnesses.Cell-based therapy using ECM-producing chondrogenic derivatives of MSCs has the potential to restore the functionality of the intervertebral disc(IVD).AIM To investigate the potential of chondrogenic transcription factors to promote differentiation of human umbilical cord MSCs into chondrocytes,and to assess their therapeutic potential in IVD regeneration.METHODS MSCs were isolated and characterized morphologically and immunologically by the expression of specific markers.MSCs were then transfected with Sox-9 and Six-1 transcription factors to direct differentiation and were assessed for chondrogenic lineage based on the expression of specific markers.These differentiated MSCs were implanted in the rat model of IVDD.The regenerative potential of transplanted cells was investigated using histochemical and molecular analyses of IVDs.RESULTS Isolated cells showed fibroblast-like morphology and expressed CD105,CD90,CD73,CD29,and Vimentin but not CD45 antigens.Overexpression of Sox-9 and Six-1 greatly enhanced the gene expression of transforming growth factor beta-1 gene,BMP,Sox-9,Six-1,and Aggrecan,and protein expression of Sox-9 and Six-1.The implanted cells integrated,survived,and homed in the degenerated intervertebral disc.Histological grading showed that the transfected MSCs regenerated the IVD and restored normal architecture.CONCLUSION Genetically modified MSCs accelerate cartilage regeneration,providing a unique opportunity and impetus for stem cell-based therapeutic approach for degenerative disc diseases.

关键词： Intervertebral disc degeneration Human umbilical cord Transcription factors Mesenchymal stem cells Gene expression Regeneration

Overexpression of GATA binding protein 4 and myocyte enhancer factor 2C induces differentiation of mesenchymal stem cells into cardiac-like cells

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World Journal of Stem Cells 2022年第9期14卷 700-713页

作者： Syeda Saima Razzaq Irfan khan Nadia Naeem asmat Salim Sumreen Begum Kanwal Haneef University of Karachi Karachi 75270Pakistan Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological SciencesUniversity of KarachiKarachi 75270Pakistan Dow Research Institute of Biotechnology&Biomedical Sciences(DRIBBS) Dow University of Health Sciences(DUHS)Ojha CampusKarachi 75200Pakistan Stem Cells Research Laboratory(SCRL) Sindh Institute of Urology and Transplantation(SIUT)Karachi 74200Pakistan

BACKGROUND Heart diseases are the primary cause of death all over the world.Following myocardial infarction,billions of cells die,resulting in a huge loss of cardiac function.Stem cell-based therapies have appeared as a new area to support heart regeneration.The transcription factors GATA binding protein 4(GATA-4)and myocyte enhancer factor 2C(MEF2C)are considered prominent factors in the development of the cardiovascular system.AIM To explore the potential of GATA-4 and MEF2C for the cardiac differentiation of human umbilical cord mesenchymal stem cells(hUC-MSCs).METHODS hUC-MSCs were characterized morphologically and immunologically by the presence of specific markers of MSCs via immunocytochemistry and flow cytometry,and by their potential to differentiate into osteocytes and adipocytes.hUC-MSCs were transfected with GATA-4,MEF2C,and their combination to direct the differentiation.Cardiac differentiation was confirmed by semiquant itative real-time polymerase chain reaction and immunocytochemistry.RESULTS hUC-MSCs expressed specific cell surface markers CD105,CD90,CD44,and vimentin but lack the expression of CD45.The transcription factors GATA-4 and MEF2C,and their combination induced differentiation in hUC-MSCs with significant expression of cardiac genes i.e.,GATA-4,MEF2C,NK2 homeobox 5(NKX2.5),MHC,and connexin-43,and cardiac proteins GATA-4,NKX2.5,cardiac troponin T,and connexin-43.CONCLUSION Transfection with GATA-4,MEF2C,and their combination effectively induces cardiac differentiation in hUC-MSCs.These genetically modified MSCs could be a promising treatment option for heart diseases in the future.

关键词： Heart disease GATA binding protein 4 Myocyte enhancer factor 2C Transcription factors Differentiation Human umbilical cord-mesenchymal stem cells

Zinc enhances the cell adhesion,migration,and self-renewal potential of human umbilical cord derived mesenchymal stem cells

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World Journal of Stem Cells 2023年第7期15卷 751-767页

作者： Iqra Sahibdad Shumaila Khalid G Rasul Chaudhry asmat Salim Sumreen Begum Irfan khan Dr.Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological SciencesUniversity of KarachiKarachi 75270SindhPakistan Department of Biological Sciences Oakland UniversityRochesterMI 48309United States Stem Cell Research Laboratory(SCRL) Sindh Institute of Urology and Transplantation(SIUT)Karachi 74200SindhPakistan

BACKGROUND Zinc(Zn)is the second most abundant trace element after Fe,present in the human body.It is frequently reported in association with cell growth and proliferation,and its deficiency is considered to be a major disease contributing factor.AIM To determine the effect of Zn on in vitro growth and proliferation of human umbilical cord(hUC)-derived mesenchymal stem cells(MSCs).METHODS hUC-MSCs were isolated from human umbilical cord tissue and characterized based on immunocytochemistry,immunophenotyping,and tri-lineage differentiation.The impact of Zn on cytotoxicity and proliferation was determined by MTT and Alamar blue assay.To determine the effect of Zn on population doubling time(PDT),hUC-MSCs were cultured in media with and without Zn for several passages.An in vitro scratch assay was performed to analyze the effect of Zn on the wound healing and migration capability of hUC-MSCs.A cell adhesion assay was used to test the surface adhesiveness of hUC-MSCs.Transcriptional analysis of genes involved in the cell cycle,proliferation,migration,and selfrenewal of hUC-MSCs was performed by quantitative real-time polymerase chain reaction.The protein expression of Lin28,a pluripotency marker,was analyzed by immunocytochemistry.RESULTS Zn at lower concentrations enhanced the rate of proliferation but at higher concentrations(>100μM),showed concentration dependent cytotoxicity in hUC-MSCs.hUC-MSCs treated with Zn exhibited a significantly greater healing and migration rate compared to untreated cells.Zn also increased the cell adhesion rate,and colony forming efficiency(CFE).In addition,Zn upregulated the expression of genes involved in the cell cycle(CDC20,CDK1,CCNA2,CDCA2),proliferation(transforming growth factorβ1,GDF5,hypoxia-inducible factor 1α),migration(CXCR4,VCAM1,VEGF-A),and self-renewal(OCT4,SOX2,NANOG)of hUC-MSCs.Expression of Lin28 protein was significantly increased in cells treated with Zn.CONCLUSION Our findings suggest that zinc enhances the proliferation rate of hUC-MSCs decreasing the PDT,and main

关键词： Human umbilical cord Mesenchymal stem cells Zinc Cell proliferation In vitro expansion

Combination of mesenchymal stem cells and three-dimensional collagen scaffold preserves ventricular remodeling in rat myocardial infarction model

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World Journal of Stem Cells 2022年第8期14卷 633-657页

作者： Rida-e-Maria Qazi Irfan khan Kanwal Haneef Tuba Shakil Malick Nadia Naeem Waqas Ahmad asmat Salim Sadia Mohsin Stem Cell Laboratory Dr.Panjwani Center for Molecular Medicine and Drug ResearchICCBSUniversity of KarachiKarachi 75270SindhPakistan Dr.Zafar H.Zaidi Center for Proteomics University of KarachiKarachi 75270SindhPakistan Dow Research Institute of Biotechnology and Biomedical Sciences(DRIBBS) Dow University of Health and SciencesOjha CampusKarachi 74200SindhPakistan Cardiovascular Research Center Lewis Katz School of MedicineTemple UniversityPhiladelphiaPA 19140United States

BACKGROUND Cardiovascular diseases are the major cause of mortality worldwide.Regeneration of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart tissue.Cardiac tissue engineering using biomaterial scaffolds combined with stem cells and bioactive molecules could be a highly promising approach for cardiac repair.Use of biomaterials can provide suitable microenvironment to the cells and can solve cell engraftment problems associated with cell transplantation alone.Mesenchymal stem cells(MSCs)are potential candidates in cardiac tissue engineering because of their multilineage differentiation potential and ease of isolation.Use of DNA methyl transferase inhibitor,such as zebularine,in combination with three-dimensional(3D)scaffold can promote efficient MSC differentiation into cardiac lineage,as epigenetic modifications play a fundamental role in determining cell fate and lineage specific gene expression.AIM To investigate the role of collagen scaffold and zebularine in the differentiation of rat bone marrow(BM)-MSCs and their subsequent in vivo effects.METHODS MSCs were isolated from rat BM and characterized morphologically,immunophenotypically and by multilineage differentiation potential.MSCs were seeded in collagen scaffold and treated with 3μmol/L zebularine in three different ways.Cytotoxicity analysis was done and cardiac differentiation was analyzed at the gene and protein levels.Treated and untreated MSC-seeded scaffolds were transplanted in the rat myocardial infarction(MI)model and cardiac function was assessed by echocardiography.Cell tracking was performed by DiI dye labeling,while regeneration and neovascularization were evaluated by histological and immunohistochemical analysis,respectively.RESULTS MSCs were successfully isolated and seeded in collagen scaffold.Cytotoxicity analysis revealed that zebularine was not cytotoxic in any of the treatment groups.Cardiac differentiation analysis showed more pronounced results in the type 3 tre

关键词： Mesenchymal stem cells Myocardial infarction Cardiac tissue engineering Demethylating agent Collagen scaffold Zebularine

Multiquadric Radial Basis Function Approximation Scheme for Solution of Total Variation Based Multiplicative Noise Removal Model

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Computer Modeling in Engineering & Sciences 2021年第1期126卷 55-88页

作者： Mushtaq Ahmad khan Ahmed BAltamimi Zawar Hussain khan Khurram Shehzad Khattak Sahib khan asmat ullah Murtaza Ali University of Engineering and Technology Mardan23200Pakistan University of Hail HailSaudi Arabia University of Engineering and Technology Peshawar25000Pakistan Politecnico di Torino Torino10129Italy

This article introduces a fastmeshless algorithm for the numerical solution nonlinear partial differential equations(PDE)by Radial Basis Functions(RBFs)approximation connected with the Total Variation(TV)-basedminimization functional and to show its application to image denoising containing multiplicative noise.These capabilities used within the proposed algorithm have not only the quality of image denoising,edge preservation but also the property of minimization of staircase effect which results in blocky effects in the images.It is worth mentioning that the recommended method can be easily employed for nonlinear problems due to the lack of dependence on a mesh or integration procedure.The numerical investigations and corresponding examples prove the effectiveness of the recommended algorithm regarding the robustness and visual improvement as well as peak-signal-to-noise ratio(PSNR),signal-to-noise ratio(SNR),and structural similarity index(SSIM)corresponded to the current conventional TV-based schemes.

关键词： Denoised image multiplicative and speckle noises total variation(TV)filter Euler-Lagrange restoration equation multiquadric radial basis functions meshless and mesh-based schemes

Wnt signaling pathway inhibitor promotes mesenchymal stem cells differentiation into cardiac progenitor cells in vitro and improves cardiomyopathy in vivo

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世界干细胞杂志:英文版(电子版) 2023年第8期15卷 821-841页

作者： Rabbia Muneer Rida-e-Maria Qazi Abiha Fatima Waqas Ahmad asmat Salim Luciana Dini Irfan khan Dr.Panjwani Center for Molecular Medicine and Drug Research International Center for Chemical and Biological SciencesUniversity of KarachiKarachi 75270SindhPakistan Department of Biology and Biotechnologies Charles Darwin Sapienza University of RomeRome 00185Italy

BACKGROUND Cardiovascular diseases particularly myocardial infarction(MI)are the leading cause of mortality and morbidity around the globe.As cardiac tissue possesses very limited regeneration potential,therefore use of a potent small molecule,inhibitor Wnt production-4(IWP-4)for stem cell differentiation into cardiomyocytes could be a promising approach for cardiac regeneration.Wnt pathway inhibitors may help stem cells in their fate determination towards cardiomyogenic lineage and provide better homing and survival of cells in vivo.Mesenchymal stem cells(MSCs)derived from the human umbilical cord have the potential to regenerate cardiac tissue,as they are easy to isolate and possess multilineage differentiation capability.IWP-4 may promote the differentiation of MSCs into the cardiac lineage.AIM To evaluate the cardiac differentiation ability of IWP-4 and its subsequent in vivo effects.METHODS Umbilical cord tissue of human origin was utilized to isolate the MSCs which were characterized by their morphology,immunophenotyping of surface markers specific to MSCs,as well as by tri-lineage differentiation capability.Cytotoxicity analysis was performed to identify the optimal concentration of IWP-4.MSCs were treated with 5μM IWP-4 at two different time intervals.Differentiation of MSCs into cardiomyocytes was evaluated at DNA and protein levels.The MI ratmodel was developed.IWP-4 treated as well as untreated MSCs were implanted in the MI model,then the cardiac function was analyzed via echocardiography.MSCs were labeled with 1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate(DiI)dye for tracking,while the regeneration of infarcted myocardium was examined by histology and immunohistochemistry.RESULTS MSCs were isolated and characterized.Cytotoxicity analysis showed that IWP-4 was non-cytotoxic at 5μM concentration.Cardiac specific gene and protein expression analyses exhibited more remarkable results in fourteen days treated group that was eventually selected for in vivo transplantation.Cardiac functi

关键词： Myocardial infarction Inhibitor Wnt production-4 Differentiation Mesenchymal stem cells Wnt pathway Cardiac function

An Energy-Efficient 12b 2.56 MS/s SAR ADC Using Successive Scaling of Reference Voltages

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Computers, Materials & Continua 2022年第7期72卷 2127-2139页

作者： Hojin Kang Syed asmat Ali Shah HyungWon Kim Department of Electronics Engineering College of Electrical and Computer EngineeringChungbuk National UniversityCheongju28644Korea Department of Electrical and Computer Engineering COMSATS University IslamabadAbbottabad CampusAbbottabad22060Pakistan

This paper presents an energy efficient architecture for successive approximation register(SAR)analog to digital converter(ADC).SAR ADCs with a capacitor array structure have been widely used because of its simple architecture and relatively high speed.However,conventional SAR ADCs consume relatively high energy due to the large number of capacitors used in the capacitor array and their sizes scaled up along with the number of bits.The proposed architecture reduces the energy consumption as well as the capacitor size by employing a new array architecture that scales down the reference voltages instead of scaling up the capacitor sizes.The proposed 12-bit SAR ADC is implemented in Complementary Metal Oxide Semiconductor(CMOS)0.13 um library using Cadence Virtuoso design tool.Simulation results and mathematical model demonstrate the overall energy savings of up to 97.3%compared with conventional SAR ADC,67%compared with the SAR ADC with split capacitor,and 35%compared with the resistor and capacitor(R&C)Hybrid SAR ADC.The ADC achieves an effective number of bits(ENOB)of 11.27 bits and consumes 61.7 uW at sampling rate of 2.56 MS/s,offering an energy consumption of 9.8 fJ per conversion step.The proposed SAR ADC offers 95.5%reduction in chip core area compared to conventional architecture,while occupying an active area of 0.088 mm2.

关键词： Low voltage low power successive approximation register analog to digital converter switching energy