1
|
Muhammad W, Zhang Y, Zhu J, Xie J, Wang S, Wang R, Feng B, Zhou J, Chen W, Xu Y, Yao Q, Yu Y, Cao H, Gao C. Co-delivery of azithromycin and ibuprofen by ROS-responsive polymer nanoparticles synergistically attenuates the acute lung injury. Biomater Adv 2023; 154:213621. [PMID: 37714042 DOI: 10.1016/j.bioadv.2023.213621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Revised: 08/22/2023] [Accepted: 09/04/2023] [Indexed: 09/17/2023]
Abstract
Bacterial infection causes lung inflammation and recruitment of several inflammatory factors that may result in acute lung injury (ALI). During bacterial infection, reactive oxygen species (ROS) and other signaling pathways are activated, which intensify inflammation and increase ALI-related mortality and morbidity. To improve the ALI therapy outcome, it is imperative clinically to manage bacterial infection and excessive inflammation simultaneously. Herein, a synergistic nanoplatform (AZI+IBF@NPs) constituted of ROS-responsive polymers (PFTU), and antibiotic (azithromycin, AZI) and anti-inflammatory drug (ibuprofen, IBF) was developed to enable an antioxidative effect, eliminate bacteria, and modulate the inflammatory milieu in ALI. The ROS-responsive NPs (PFTU NPs) loaded with dual-drugs (AZI and IBF) scavenged excessive ROS efficiently both in vitro and in vivo. The AZI+IBF@NPs eradicated Pseudomonas aeruginosa (PA) bacterial strain successfully. To imitate the entry of bacterial-derived compounds in body, a lipopolysaccharide (LPS) model was adopted. The administration of AZI+IBF@NPs via the tail veins dramatically reduced the number of neutrophils, significantly reduced cell apoptosis and total protein concentration in vivo. Furthermore, nucleotide oligomerization domain-like receptor thermal protein domain associated protein 3 (NLRP3) and Interleukin-1 beta (IL-1β) expressions were most effectively inhibited by the AZI+IBF@NPs. These findings present a novel nanoplatform for the effective treatment of ALI.
Collapse
Affiliation(s)
- Wali Muhammad
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310058, China
| | - Yiru Zhang
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Jiaqi Zhu
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Jieqi Xie
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310058, China
| | - Shuqin Wang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310058, China
| | - Ruo Wang
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Bing Feng
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Jiahang Zhou
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Wenyi Chen
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Yanping Xu
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Qigu Yao
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Yingduo Yu
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Hongcui Cao
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China.
| | - Changyou Gao
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310058, China; Center for Healthcare Materials, Shaoxing Institute, Zhejiang University, Shaoxing 312099, China.
| |
Collapse
|
2
|
Muhammad W, Zhu J, Zhai Z, Xie J, Zhou J, Feng X, Feng B, Pan Q, Li S, Venkatesan R, Li P, Cao H, Gao C. ROS-responsive polymer nanoparticles with enhanced loading of dexamethasone effectively modulate the lung injury microenvironment. Acta Biomater 2022; 148:258-270. [PMID: 35724918 PMCID: PMC9212862 DOI: 10.1016/j.actbio.2022.06.024] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 06/09/2022] [Accepted: 06/10/2022] [Indexed: 11/30/2022]
Abstract
The acute lung injury (ALI) is an inflammatory disorder associated with cytokine storm, which activates various reactive oxygen species (ROS) signaling pathways and causes severe complications in patients as currently seen in coronavirus disease 2019 (COVID-19). There is an urgent need for medication of the inflammatory lung environment and effective delivery of drugs to lung to reduce the burden of high doses of medications and attenuate inflammatory cells and pathways. Herein, we prepared dexamethasone-loaded ROS-responsive polymer nanoparticles (PFTU@DEX NPs) by a modified emulsion approach, which achieved high loading content of DEX (11.61 %). DEX was released faster from the PFTU@DEX NPs in a ROS environment, which could scavenge excessive ROS efficiently both in vitro and in vivo. The PFTU NPs and PFTU@DEX NPs showed no hemolysis and cytotoxicity. Free DEX, PFTU NPs and PFTU@DEX NPs shifted M1 macrophages to M2 macrophages in RAW264.7 cells, and showed anti-inflammatory modulation to A549 cells in vitro. The PFTU@DEX NPs treatment significantly reduced the increased total protein concentration in BALF of ALI mice. The delivery of PFTU@DEX NPs decreased the proportion of neutrophils significantly, mitigated the cell apoptosis remarkably compared to the other groups, reduced M1 macrophages and increased M2 macrophages in vivo. Moreover, the PFTU@DEX NPs had the strongest ability to suppress the expression of NLRP3, Caspase1, and IL-1β. Therefore, the PFTU@DEX NPs could efficiently suppress inflammatory cells, ROS signaling pathways, and cell apoptosis to ameliorate LPS-induced ALI. STATEMENT OF SIGNIFICANCE: The acute lung injury (ALI) is an inflammatory disorder associated with cytokine storm, which activates various reactive oxygen species (ROS) signaling pathways and causes severe complications in patients. There is an urgent need for medication of the inflammatory lung environment and effective delivery of drugs to modulate the inflammatory disorder and suppress the expression of ROS and inflammatory cytokines. The inhaled PFTU@DEX NPs prepared through a modified nanoemulsification method suppressed the activation of NLRP3, induced the polarization of macrophage phenotype from M1 to M2, and thereby reduced the neutrophil infiltration, inhibited the release of proteins and inflammatory mediators, and thus decreased the acute lung injury in vivo.
Collapse
Affiliation(s)
- Wali Muhammad
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Jiaqi Zhu
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Zihe Zhai
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Jieqi Xie
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Jiahang Zhou
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Xudong Feng
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Bing Feng
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Qiaoling Pan
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Shifen Li
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Rajiu Venkatesan
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Pan Li
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China
| | - Hongcui Cao
- State Key Laboratory for the Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, 79 Qingchun Rd., Hangzhou 310003, China.
| | - Changyou Gao
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
| |
Collapse
|
3
|
Nakkala JR, Duan Y, Ding J, Muhammad W, Zhang D, Mao Z, Ouyang H, Gao C. Macrophage membrane-functionalized nanofibrous mats and their immunomodulatory effects on macrophage polarization. Acta Biomater 2022; 141:24-38. [PMID: 34958971 DOI: 10.1016/j.actbio.2021.12.026] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 12/18/2021] [Accepted: 12/21/2021] [Indexed: 01/04/2023]
Abstract
Immunomodulation is an important phenomenon in the normal mammalian host response toward an injury, and plays a critical role in tissue regeneration and regenerative medicine. Different phenotypes of macrophages show an array of activation states compassing pro-inflammatory to pro-alleviating cells, which are the critical players to modulate immune response and tissue regeneration. In this study, macrophage membranes of different phenotypes (macrophages (M0), classically activated macrophages (M1) and alternatively activated macrophages (M2)) were coated onto poly-ε-caprolactone (PCL) nanofibers to acquire exterior surface proteins and similar functions of the natural membranes. In vitro results unveiled that these nanofibers, especially the M2-PCL nanofibers, can suppress the activities of inflammatory markers such as TNF-α and IL-1β, and stimulate anti-inflammatory markers such as Arg-1, IL-10 and TGF-β. In a C57BL/6 mouse model, the macrophage membrane-coated nanofibers, especially the M2-PCL nanofibers, displayed minimal cellular infiltration and low collagen deposition, increased anti-inflammatory CD206 and decreased inflammatory CD86 levels. The M2-PCL nanofibers most effectively neutralized inflammatory chemokines, regulated the expression of inflammation-associated genes as well as anti-inflammatory genes, and showed strong immunomodulatory effects than the PCL, M0-PCL and M1-PCL nanofibers. STATEMENT OF SIGNIFICANCE: Different types of macrophage membrane-functionalized PCL nanofibers were successfully prepared and well characterized. They inherited the surface proteins imitating the source macrophages, and played an important role in limiting cellular infiltration and collagen deposition. These different macrophages and their membrane-coated nanofibers (M0-PCL, M1-PCL and M2-PCL) behaved like their respective source cells. The M2 mimicking M2-PCL nanofibers effectively polarized macrophages to M2 phenotype and decreased the expression of inflammation-associated chemokines and promoted the anti-inflammation in vitro and in vivo, which is critical for tissue regeneration. The mice implanted with the bio-mimicking M2-PCL nanofibers effectively inhibited toll like receptors signaling induced NF-kB and IRF-5 and their target genes such as Edn-1, IL-6, iNOS, TNF-α, etc. compared to the PCL, and M0-PCL and M1-PCL macrophage membrane-coated nanofibers.
Collapse
Affiliation(s)
- Jayachandra Reddy Nakkala
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China; Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang University, Hangzhou 310058, China
| | - Yiyuan Duan
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China; Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang University, Hangzhou 310058, China
| | - Jie Ding
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China; Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang University, Hangzhou 310058, China
| | - Wali Muhammad
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Deteng Zhang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China; Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang University, Hangzhou 310058, China
| | - Zhengwei Mao
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Hongwei Ouyang
- Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang University, Hangzhou 310058, China
| | - Changyou Gao
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China; Dr. Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine, Zhejiang University, Hangzhou 310058, China.
| |
Collapse
|
4
|
Muhammad W, Zhai Z, Wang S, Gao C. Inflammation-modulating nanoparticles for pneumonia therapy. Wiley Interdiscip Rev Nanomed Nanobiotechnol 2021; 14:e1763. [PMID: 34713969 DOI: 10.1002/wnan.1763] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 10/07/2021] [Accepted: 10/08/2021] [Indexed: 12/23/2022]
Abstract
Pneumonia is a common but serious infectious disease, and is the sixth leading cause for death. The foreign pathogens such as viruses, fungi, and bacteria establish an inflammation response after interaction with lung, leading to the filling of bronchioles and alveoli with fluids. Although the pharmacotherapies have shown their great effectiveness to combat pathogens, advanced methods are under developing to treat complicated cases such as virus-infection and lung inflammation or acute lung injury (ALI). The inflammation modulation nanoparticles (NPs) can effectively suppress immune cells and inhibit inflammatory molecules in the lung site, and thereby alleviate pneumonia and ALI. In this review, the pathological inflammatory microenvironments in pneumonia, which are instructive for the design of biomaterials therapy, are summarized. The focus is then paid to the inflammation-modulating NPs that modulate the inflammatory cells, cytokines and chemokines, and microenvironments of pneumonia for better therapeutic effects. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Respiratory Disease.
Collapse
Affiliation(s)
- Wali Muhammad
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
| | - Zihe Zhai
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
| | - Shuqin Wang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
| | - Changyou Gao
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, China
| |
Collapse
|
5
|
Ahmed T, Muhammad W, Mushtaq Z, Bhatty MB, Zaigham H. Mechanical Behavior of Friction Stir Welded AA-6061 Thick Plates in Different Heat Treatment Conditions. KEM 2021; 875:203-210. [DOI: 10.4028/www.scientific.net/kem.875.203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
In this study, mechanical properties of friction stir welded Aluminum Alloy (AA) 6061 in three different heat treatment conditions i.e. Annealed (O), Artificially aged (T6) and Post Weld Heat Treated (PWHT) were compared. Plates were welded in a butt joint form. Parameters were optimized and joints were fabricated using tool rotational speed and travel speed of 500 rpm and 350 mm/min respectively. Two sets of plates were welded in O condition and out of which one was, later, subjected to post weld artificial aging treatment. Third set was welded in T6 condition. The welds were characterized by macro and microstructure analysis, microhardness measurement and mechanical testing. SEM fractography of the tensile fracture surfaces was also performed. Comparatively better mechanical properties were achieved in the plate with PWHT condition.
Collapse
Affiliation(s)
- Talha Ahmed
- Institute of Industrial Control Systems (IICS)
| | | | | | | | | |
Collapse
|
6
|
Ahmed T, Muhammad W, Bhatty MB, Zillohu AU, Zaigham H. Optimization of Maximum Tool Travel Speed for Friction Stir Welded AA-2014-T6 without Compromising the Mechanical Properties. KEM 2021; 875:219-226. [DOI: 10.4028/www.scientific.net/kem.875.219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
In this study optimization of maximum travel speed that can be achieved for Friction Stir Welding of Aluminum Alloy 2014-T6 without compromising the mechanical properties was carried out. Joints were made at different travel speeds of 200, 300, 400, 500 and 600 mm/min with constant tool rotational speed of 800 rpm and tool tilt angle of 2.The samples were characterized by stereo microscopy, optical microscopy, scanning electron microscopy, Vickers microhardness testing and tensile testing. Microstructural features of as-welded samples revealed refined equiaxed grains in nugget zone and grain growth in the heat effected zone. Tensile test results showed that the tensile strength was maximum at travel speed of 500 mm/min but then decreased after further increasing the travel speed. Hardness in the nugget zones of all welds was lower than that of base material. Fractographic analysis exhibited significant variations in fracture surfaces of tensile samples. A relationship between the welding parameters and resultant heat inputs was also discussed.
Collapse
Affiliation(s)
- Talha Ahmed
- Institute of Industrial Control Systems (IICS)
| | | | | | | | | |
Collapse
|
7
|
Muhammad W, Javed H, Ahmad M, Mukhtar T. Optimizing Transplanting Dates for the Management of Brinjal Shoot and Fruit Borer and Better Crop Yield under Field Conditions. PAK J ZOOL 2021. [DOI: 10.17582/journal.pjz/20200103180112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
8
|
Abstract
One of the challenges facing by world nowadays is the generation of new pathogens that cause public health issues. Coronavirus (CoV) is one of the severe pathogens that possess the RNA (ribonucleic acid) envelop, and extensively infect humans, birds, and other mammals. The novel strain "SARS-CoV-2" (severe acute respiratory syndrome coronavirus-2) causes deadly infection all over the world and presents a pandemic situation nowadays. The SARS-CoV-2 has 40 different strains that create a worrying situation for health authorities. The virus develops serious pneumonia in infected persons and causes severe damage to the lungs. There is no vaccine available for this virus up to present. To cure this type of infections by making vaccines and antiviral drugs is still a major challenge for researchers. Nanotechnology covering a multidisciplinary field may find the solution to this lethal infection. The interaction of nanomaterials and microorganisms is considered as a potential treatment method because the nanomaterials owe unique physicochemical properties. The aim of this review is to present an overview of previous and recent studies of nanomaterials against coronaviruses and to provide possible new strategies for upcoming research using the nanotechnology platform.
Collapse
Affiliation(s)
- Wali Muhammad
- W. Muhammad, Z. Zhai, Prof. C. Gao, MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Zihe Zhai
- W. Muhammad, Z. Zhai, Prof. C. Gao, MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Changyou Gao
- W. Muhammad, Z. Zhai, Prof. C. Gao, MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| |
Collapse
|
9
|
Hameed S, Ali Shah S, Iqbal J, Numan M, Muhammad W, Junaid M, Shah S, Khurshid R, Umer F. Cannabis sativa-mediated synthesis of gold nanoparticles and their biomedical properties. Bioinspired, Biomimetic and Nanobiomaterials 2020. [DOI: 10.1680/jbibn.19.00023] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Safia Hameed
- Department of Biotechnology, Quaid-i-Azam University, Islamabad, Pakistan
| | - Sajjad Ali Shah
- Department of Biotechnology, Bacha Khan University Charsadda, Charsadda, Pakistan
| | - Javed Iqbal
- Department of Plant Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Muhammad Numan
- Department of Biotechnology, Quaid-i-Azam University, Islamabad, Pakistan
| | - Wali Muhammad
- Department of Biotechnology, Quaid-i-Azam University, Islamabad, Pakistan
| | - Muhammad Junaid
- Department of Biotechnology, Bacha Khan University Charsadda, Charsadda, Pakistan
| | - Sumaira Shah
- Department of Botany, Bacha Khan University Charsadda, Charsadda, Pakistan
| | - Razia Khurshid
- Department of Biotechnology, Quaid-i-Azam University, Islamabad, Pakistan
| | - Fazal Umer
- Department of Biotechnology, Bacha Khan University Charsadda, Charsadda, Pakistan
| |
Collapse
|
10
|
Ding J, Venkatesan R, Zhai Z, Muhammad W, Nakkala JR, Gao C. Micro- and nanoparticles-based immunoregulation of macrophages for tissue repair and regeneration. Colloids Surf B Biointerfaces 2020; 192:111075. [PMID: 32403015 DOI: 10.1016/j.colsurfb.2020.111075] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 03/27/2020] [Accepted: 04/20/2020] [Indexed: 12/16/2022]
Abstract
The importance of inflammatory tissue microenvironment on the repair and regeneration of tissues and organs has been well recognized. In particular, the phenotypes of macrophages can significantly influence on the processes of tissue repair and remodeling. Among the many types of biomaterials, the particles in the range from nanometers to submicron meters have been extensively studied and applied in tissue engineering and regenerative medicine. They can actively interact with cells in different levels, and show the ability to regulate the polarization of macrophages. In this review, the influence of physicochemical properties such as size, surface charge, chemical components and surface modification of micro-nanoparticles on the immune behavior of macrophages, including endocytosis and phenotype switch, shall be introduced. The important roles of nanoparticles-based immunoregulation of macrophages on the chronic skin wounds regeneration, myocardial repair, liver repair and bone regeneration are discussed.
Collapse
Affiliation(s)
- Jie Ding
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Rajiu Venkatesan
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Zihe Zhai
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Wali Muhammad
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Jayachandra Reddy Nakkala
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China
| | - Changyou Gao
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
| |
Collapse
|
11
|
Muhammad W, Hart G, Nartowt B, Deng J. In silico Simulation to Quantify Liver Cancer Risk with Smoking. Int J Radiat Oncol Biol Phys 2019. [DOI: 10.1016/j.ijrobp.2019.06.2175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
12
|
Liang Y, Muhammad W, Hart G, Nartowt B, Deng J. A Prototype of a Personal Organ Dose Archive for Accurate Organ Dose Tracking in Radiotherapy. Int J Radiat Oncol Biol Phys 2019. [DOI: 10.1016/j.ijrobp.2019.06.1119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
13
|
Hart G, Nartowt B, Muhammad W, Liang Y, Huang G, Deng J. Endometrial Cancer Risk Prediction and Stratification Using Personal Health Data. Int J Radiat Oncol Biol Phys 2019. [DOI: 10.1016/j.ijrobp.2019.06.2170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
14
|
Abbasi BH, Nazir M, Muhammad W, Hashmi SS, Abbasi R, Rahman L, Hano C. A Comparative Evaluation of the Antiproliferative Activity against HepG2 Liver Carcinoma Cells of Plant-Derived Silver Nanoparticles from Basil Extracts with Contrasting Anthocyanin Contents. Biomolecules 2019; 9:E320. [PMID: 31366167 PMCID: PMC6722760 DOI: 10.3390/biom9080320] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 07/24/2019] [Accepted: 07/29/2019] [Indexed: 01/16/2023] Open
Abstract
Nanotechnology is a well-established and revolutionized field with diverse therapeutic properties. Several methods have been employed using different reducing agents to synthesize silver nanoparticles (AgNPs). Chemical mediated synthetic methods are toxic and resulted in non-desired effects on biological systems. Herein, we, synthesized silver nanoparticles using callus extract of purple basil (BC-AgNPs) and anthocyanin extract deriving from the same plant (i.e. purple basil) (AE-AgNPs), and systematically investigated their antiproliferative potential against HepG2 Liver Carcinoma Cells. The phyto-fabricated AgNPs were characterized by different techniques like UV-visible spectroscopy (UV-Vis), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM) and Energy dispersive X-rays (EDX). Morphologically, both types of NPs were found spherical. The average size of BC-AgNPs and AE-AgNPs as revealed through XRD and SEM analyses were calculated as 50.97 ± 0.10 nm and 42.73 ± 1.24 nm, respectively. FT-IR spectral analysis demonstrates the existence of possible phytochemicals required for the capping and reduction of Ag ions. Herein, following solid phase extraction (SPE) coupled to HPLC analysis, we report for the first-time the anthocyanin mediated synthesis of AgNPs and conforming the successful capping of anthocyanin. Small sized AE-AgNPs showed significant cytotoxic effect against human hepatocellular carcinoma (HepG2) cell line as compared to BC-AgNPs. Therefore, the results revealed that the prevalent group of flavonoids present in purple basil is the anthocyanins and AE-AgNPs could be employed as potential anticancer agents in future treatments strategies.
Collapse
Affiliation(s)
- Bilal Haider Abbasi
- Department of Biotechnology, Quaid-i-Azam University, Islamabad 45320, Pakistan.
- Laboratoire de Biologie des Ligneux et des Grandes Cultures (LBLGC), Plant Lignans Team, INRA USC1328, Université d'Orléans, F 28000 Chartres, France.
- EA2106 Biomolécules et Biotechnologies Végétales, Université de Tours, 37000 Tours, France.
| | - Munazza Nazir
- Department of Biotechnology, Quaid-i-Azam University, Islamabad 45320, Pakistan
- Department of Botany, University of Azad Jammu & Kashmir Muzaffarabad, Azad Kashmir 13230, Pakistan
| | - Wali Muhammad
- Department of Biotechnology, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Syed Salman Hashmi
- Department of Biotechnology, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Rashda Abbasi
- Institute of Biomedical & Genetic Engineering (IBGE), Sector G-9/1, Islamabad 45320, Pakistan
| | - Lubna Rahman
- Department of Biotechnology, Quaid-i-Azam University, Islamabad 45320, Pakistan
| | - Christophe Hano
- Laboratoire de Biologie des Ligneux et des Grandes Cultures (LBLGC), Plant Lignans Team, INRA USC1328, Université d'Orléans, F 28000 Chartres, France.
| |
Collapse
|
15
|
Muhammad W, Ullah N, Haroon M, Abbasi BH. Optical, morphological and biological analysis of zinc oxide nanoparticles (ZnO NPs) using Papaver somniferum L. RSC Adv 2019; 9:29541-29548. [PMID: 35531532 PMCID: PMC9071912 DOI: 10.1039/c9ra04424h] [Citation(s) in RCA: 112] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 08/28/2019] [Indexed: 12/25/2022] Open
Abstract
Biogenic synthesis of ZnO-NPs using P. somniferum.
Collapse
Affiliation(s)
- Wali Muhammad
- Department of Biotechnology
- Quaid-i-Azam University
- Islamabad
- Pakistan
| | - Naimat Ullah
- Department of Chemistry
- Quaid-i-Azam University
- Islamabad
- Pakistan
| | - Muhammad Haroon
- Department of Biotechnology
- Quaid-i-Azam University
- Islamabad
- Pakistan
| | | |
Collapse
|
16
|
Nartowt B, Hart G, Ali I, Muhammad W, Liang Y, Roffman D, Deng J. Risk-Index of Colorectal Cancer to Triage for Screening. Int J Radiat Oncol Biol Phys 2018. [DOI: 10.1016/j.ijrobp.2018.07.992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
17
|
Rix H, Meste O, Muhammad W. Estimation of Scale Factors in Presence of Multiple Signals: Application to sEMG Analysis. Methods Inf Med 2018. [DOI: 10.1055/s-0038-1634276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Abstract:When several realizations of an unknown recurrent signal are observed apart from a time expansion or compression, the classical way of estimating these time scaling factors is to take one signal as reference for the estimation. This approach does not take into account the common information between all possible couples of realizations. To achieve this task we use a Maximum-Likelihood based method, in a sub-optimal manner. Using some realistic assumptions and simplifications, we propose a tractable solution. The improvement of classical results is shown through a simulation whose conclusion is that the larger the number of realizations, the more correct the estimation. Finally, we apply the method to electrically evoked sEMG.
Collapse
|
18
|
Abstract
Summary
Objectives:
Our main objective was to propose an alternative to the technique of signal averaging (SA) to avoid shape distortions due to jittering and scale fluctuations, leading to a mean shape signal rather than to an average one.
Methods:
In case of both time shift and time scale fluctuations of the individual signals, the first point was to show what model makes it possible to interpret their expected action as a linear shift invariant filter followed by a scale invariant one. So, even in the case of equal shape signals, the average is clearly not the same shape. The second point was to propose another averaging process, using the normalized integrals and called Shape Averaging (ShA) which provides, in this case, a mean signal preserving the common shape.
Results:
The performances of ShA were firstly shown by simulation. Shifted and scaled versions of a given signal, without and with additive noise, have been generated at random. The mean shape signal obtained by ShA was compared to the shifted and scaled signal using the exact average values of the shifts and scale factors. A very good reconstruction of the mean shape signal is obtained for SNR = 20 dB and quite good for 8 dB, especially compared to SA. The method was then applied to a series of M-waves coming from surface EMG signals. In this case, the comparison of ShA with SA makes it possible to appreciate the validity of equal shape signal hypothesis.
Collapse
|
19
|
Ghanchi NK, Khan E, Khan A, Muhammad W, Malik FR, Zafar A. Naegleria fowleri Meningoencephalitis Associated with Public Water Supply, Pakistan, 2014. Emerg Infect Dis 2018; 22:1835-7. [PMID: 27648572 PMCID: PMC5038392 DOI: 10.3201/eid2210.151236] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
|
20
|
Ejaz M, Afzal MBS, Shabbir G, Serrão JE, Shad SA, Muhammad W. Laboratory selection of chlorpyrifos resistance in an Invasive Pest, Phenacoccus solenopsis (Homoptera: Pseudococcidae): Cross-resistance, stability and fitness cost. Pestic Biochem Physiol 2017; 137:8-14. [PMID: 28364807 DOI: 10.1016/j.pestbp.2016.09.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 08/27/2016] [Accepted: 09/04/2016] [Indexed: 06/07/2023]
Abstract
The cotton mealybug, Phenacoccus solenopsis is an important polyphagous sucking pest of ornamentals, horticultural and fiber crops worldwide. Some P. solenopsis populations have developed insecticide resistance. This study evaluated cross-resistance, stability of insecticide resistance and life history traits affected by chlorpyrifos resistance in P. solenopsis. After nine generations selected with chlorpyrifos, P. solenopsis exhibited a 539.76-fold resistance level compared to an unselected population (UNSEL Pop). Chlorpyrifos selected population (Chlor-SEL Pop) displayed moderate cross-resistance to profenofos, nitenpyram and high cross-resistance to lambda-cyhalothrin. Biological parameters of P. Solenopsis were affected by chlorpyrifos resistance. The Chlor-SEL Pop had a significant reduction in fitness (relative fitness=0.10), along with significant decreases in pupal weight, fecundity, egg hatching %, intrinsic rate of natural population increase, biotic potential, and mean relative growth rate. It is concluded that selection with chlorpyrifos had marked effect on resistance development in P. solenopsis and upon removal of selection pressure chlorpyrifos resistance declined significantly indicating unstable resistance. Development of resistance led to high fitness costs for the chlorpyrifos-selected strain. These findings should be helpful for better and more successful resistance management of P. solenopsis.
Collapse
Affiliation(s)
- Masood Ejaz
- Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan
| | - Muhammad Babar Shahzad Afzal
- Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan.
| | - Ghulam Shabbir
- Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan
| | - José Eduardo Serrão
- Department of General Biology, Federal University of Viçosa, 36570-000 Viçosa, MG, Brazil
| | - Sarfraz Ali Shad
- Department of Entomology, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan.
| | - Wali Muhammad
- Quality Control of Pesticides, Layyah, Punjab, Pakistan
| |
Collapse
|
21
|
Ujjan ID, Tayyib M, Tasneem T, Farooq M, Mughal MA, Akhund IA, Memon RA, Nigar R, Muhammad W, Memon AH, Khan A. A comparative study of red cell folate and serum folate levels in patients on regular Hemodialysis. Annals KEMU 2016. [DOI: 10.21649/akemu.v10i4.1254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Sixty subjects were selected and were divided into two groups. Group A included 30 patients of end stage renal disease on regular dialysis and group B included 30 normal healthy subjects as control. Absolute values and Hb were done by hematology auto analyzer and serum and red cell folate were done by commercially available kits. Results were analyzed by using Student`s `t` test and level of significance was done. A significant decreased in serum and red cell folate in end stage renal disease patients with regular dialysis as compared to control.
Collapse
|
22
|
Muhammad W, Hussain A, Asadullah. EP-1502: Effects on dosimetric measurements due to difference in calibration and dosimetry protocols followed. Radiother Oncol 2016. [DOI: 10.1016/s0167-8140(16)32752-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|
23
|
Muhammad W, Lee S, Hussain A. SU-E-T-270: Optimized Shielding Calculations for Medical Linear Accelerators (LINACs). Med Phys 2012; 39:3765. [DOI: 10.1118/1.4735337] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
24
|
Ranney DN, Englesbe MJ, Muhammad W, Al-Holou SN, Park JM, Pelletier SJ, Punch JD, Lynch RJ. Should heart, lung, and liver transplant recipients receive immunosuppression induction for kidney transplantation? Clin Transplant 2009; 24:67-72. [PMID: 19222505 DOI: 10.1111/j.1399-0012.2009.00973.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
As the outcomes of heart, liver, and lung transplantation continue to improve, more patients will present for subsequent renal transplantation. It remains unclear whether these patients benefit from induction immunosuppression. We retrospectively reviewed induction on solid organ graft recipients who underwent renal transplant at our center from January 1, 1995 to March 30, 2007. Induction and the non-induction groups were compared by univariate and Kaplan-Meier analyses. There were 21 patients in each group, with mean follow-up of 4.5-6.0 years. Forty-seven percent of patients receiving induction had a severe post-operative infection, compared with 28.6% in the non-induction group (p = NS). The one yr rejection rate in the induction group was 9.5% compared with 14.3% for non-induction (p = NS). One-yr graft survival was 81.0% and 95.2% in the induction and non-induction group (p = NS). In summary, there is a trend toward lower patient and graft survival among patients undergoing induction. These trends could relate to selection bias in the decision to prescribe induction immunosuppression, but further study is needed to better define the risks and benefits of antibody-induction regimens in this population.
Collapse
Affiliation(s)
- D N Ranney
- Department of Surgery, Division of Transplantation, University of Michigan, Ann Arbor, MI, USA
| | | | | | | | | | | | | | | |
Collapse
|
25
|
Hussain A, Ahmad SB, Muhammad W, Kakakhail MB, Matiullah. Epidemiology of the breast cancer patients registered at Institute of Radiotherapy and Nuclear Medicine, Peshawar, Pakistan. Eur J Cancer Care (Engl) 2008; 17:469-76. [PMID: 18564287 DOI: 10.1111/j.1365-2354.2007.00879.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
In Pakistan, malignant diseases are increasing day by day, but no epidemiological cancer study on large scale has been designed. The main objective of this study was to provide a baseline data on frequency, morphological types, gender and age distribution etc., of breast cancer in North-West Frontier Province and Federally Administered Tribal Areas of Pakistan, and to compare it with the published data. In this context, 2134 breast cancer patients (2059 female and 75 male) registered at Institute of Radiotherapy and Nuclear Medicine, Peshawar from 1995 to 2001, were studied. Crude incidence, standardized incidence ratios (SIR, world) and age-specific incidence rates (ASIR) were determined both for male and female patients. Same morphological distribution was found in both genders. Moreover, breast cancer was found to be the most common malignancy among the women (96.49%). Male to female breast cancer ratio was found to be 3.5 times higher than the reported data. The highest ASIR of approximately 10.6/100,000 per year among women was observed in the age group of 55-59 years. In men, the highest ASIR of 0.84/100,000 per year was observed in the age group of 65-69 years. The SIR (world) for women was 3.15/100,000 per year, while for male this was 0.13/100,000 per year.
Collapse
Affiliation(s)
- A Hussain
- Institute of Nuclear Medicine Oncology and Radiotherapy (INOR), Abbottabad, NWFP, Pakistan.
| | | | | | | | | |
Collapse
|
26
|
Hafeez A, Kiani AG, ud Din S, Muhammad W, Butt K, Shah Z, Mirza Z. Prescription and dispensing practices in public sector health facilities in Pakistan: survey report. J PAK MED ASSOC 2004; 54:187-91. [PMID: 15241995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
OBJECTIVES To gather information on existing prescription practices, dispensing practices and patient satisfaction in government health services of the NWFP, Baluchistan and Punjab province. METHODS A cross sectional study design was used for this purpose. Ten health care facilities were selected from each province keeping appropriate representation from first level health facilities, district health facilities and tertiary care hospital. Analysis of selected indicators was carried out on the basis of provinces, health facilities, gender and different age groups. RESULTS Documentation of 914 responses was completed from three provinces. Almost equal distribution of encounters was maintained representing different health facilities. Forty seven percent of encounters involved children under 15 years of age. Female patients comprised of 56% and the mean age of the entire sample was 26 years. The mean dispensing time was only 38 seconds, the mean consultation time was 1.79 minutes and the average number of drugs per prescription turned out to be 2.7 out of which only 1.6 drugs were being dispensed from the facility. More than half of the prescriptions contained antibiotics and 15% of patients were prescribed with injectables. Only half of the patients expressed satisfaction with their visit to health facility. CONCLUSIONS Like many other developing countries, prescription and dispensing practices are not satisfactory in public sector health facilities of Pakistan. Appropriate and workable solutions need to be developed and implemented in the country to improve systems. Regular audits and qualitative studies should become part of the effort.
Collapse
Affiliation(s)
- A Hafeez
- Department of Pediatrics, KRL Hospital, Islamabad
| | | | | | | | | | | | | |
Collapse
|
27
|
Rix H, Meste O, Muhammad W. Averaging signals with random time shift and time scale fluctuations. Methods Inf Med 2004; 43:13-6. [PMID: 15026828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
OBJECTIVES Our main objective was to propose an alternative to the technique of signal averaging (SA) to avoid shape distortions due to jittering and scale fluctuations, leading to a mean shape signal rather than to an average one. METHODS In case of both time shift and time scale fluctuations of the individual signals, the first point was to show what model makes it possible to interpret their expected action as a linear shift invariant filter followed by a scale invariant one. So, even in the case of equal shape signals, the average is clearly not the same shape. The second point was to propose another averaging process, using the normalized integrals and called Shape Averaging (ShA) which provides, in this case, a mean signal preserving the common shape. RESULTS The performances of ShA were firstly shown by simulation. Shifted and scaled versions of a given signal, without and with additive noise, have been generated at random. The mean shape signal obtained by ShA was compared to the shifted and scaled signal using the exact average values of the shifts and scale factors. A very good reconstruction of the mean shape signal is obtained for SNR = 20 dB and quite good for 8 dB, especially compared to SA. The method was then applied to a series of M-waves coming from surface EMG signals. In this case, the comparison of ShA with SA makes it possible to appreciate the validity of equal shape signal hypothesis.
Collapse
Affiliation(s)
- H Rix
- I3S, 2000 Route des Lucioles, BP 121, 06903 Sophia Antipolis cedex, France.
| | | | | |
Collapse
|
28
|
Farina D, Muhammad W, Fortunato E, Meste O, Merletti R, Rix H. Estimation of single motor unit conduction velocity from surface electromyogram signals detected with linear electrode arrays. Med Biol Eng Comput 2001; 39:225-36. [PMID: 11361250 DOI: 10.1007/bf02344807] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
This work addresses the problem of estimating the conduction velocity (CV) of single motor unit (MU) action potentials from surface EMG signals detected with linear electrode arrays during voluntary muscle contractions. In ideal conditions, that is without shape or scale changes of the propagating signals and with additive white Gaussian noise, the maximum likelihood (ML) is the optimum estimator of delay. Nevertheless, other methods with computational advantages can be proposed; among them, a modified version of the beamforming algorithm is presented and compared with the ML estimator. In real cases, the resolution in delay estimation in the time domain is limited because of the sampling process. Transformation to the frequency domain allows a continuous estimation. A fast, high-resolution implementation of the presented multichannel techniques in the frequency domain is proposed. This approach is affected by a negligible decrease in performance with respect to ideal interpolation. Application of the ML estimator, based on two-channel information, to ten firings of each of three MUs provides a CV estimate affected by a standard deviation of 0.5 m s(-1); the modified beamforming and ML estimators based on five channels provide a CV standard deviation of less than 0.1 m s(-1) and allow the detection of statistically significant differences between the CVs of the three MUs. CV can therefore be used for MU classification.
Collapse
Affiliation(s)
- D Farina
- Department of Electronics, Politecnico di Torino, Italy
| | | | | | | | | | | |
Collapse
|
29
|
Walters JJ, Muhammad W, Fox KF, Fox A, Xie D, Creek KE, Pirisi L. Genotyping single nucleotide polymorphisms using intact polymerase chain reaction products by electrospray quadrupole mass spectrometry. Rapid Commun Mass Spectrom 2001; 15:1752-1759. [PMID: 11555877 DOI: 10.1002/rcm.435] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Both single nucleotide polymorphisms (SNPs) and mutations are commonly observed in the gene encoding the tumor suppressor protein, p53. SNPs occur at specific locations within genes whereas mutations may be distributed across large regions of genes. When determining nucleotide differences, mass spectrometry is the only method other than Sanger sequencing which offers direct structural information. Electrospray ionization (ESI) quadrupole mass spectrometry (MS) analysis of intact polymerase chain reaction (PCR) products was performed following a simple purification and on-line heating to limit ion adduction. The PCR products were amplified directly from genomic DNA rather than plasmids, as in our previous work. Two known polymorphisms of the p53 gene were genotyped. A cytosine (C) or guanine (G) transversion, designated C <--> G (G <--> C on the opposite strand), were each detected by a 40.0 Da change upon ESI quadrupole MS analysis. Using known PCR products as standards, the genotypes determined for 10 human samples corresponded with restriction fragment length polymorphism (RFLP) analysis. Cytosine/thymine (T) transitions, designated C <--> T (G <--> A on the opposite strand), were also genotyped by ESI-MS. This SNP is discriminated by a 15.0 Da change on one strand (C <--> T) and a 16.0 Da change on the other (G <--> A). Appropriate sample preparation and instrumental configuration (including heated sample inlet syringe and MS source), to limit adducts, are both vital for successful ESI quadrupole MS analysis of intact PCR products.
Collapse
Affiliation(s)
- J J Walters
- Department of Microbiology and Immunology, University of South Carolina, School of Medicine, Columbia, SC 29208, USA
| | | | | | | | | | | | | |
Collapse
|
30
|
Meste O, Muhammad W, Rix H. Estimation of scale factors in presence of multiple signals: application to sEMG analysis. Methods Inf Med 2000; 39:138-41. [PMID: 10892248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
When several realizations of an unknown recurrent signal are observed apart from a time expansion or compression, the classical way of estimating these time scaling factors is to take one signal as reference for the estimation. This approach does not take into account the common information between all possible couples of realizations. To achieve this task we use a Maximum-Likelihood based method, in a sub-optimal manner. Using some realistic assumptions and simplifications, we propose a tractable solution. The improvement of classical results is shown through a simulation whose conclusion is that the larger the number of realizations, the more correct the estimation. Finally, we apply the method to electrically evoked sEMG.
Collapse
|
31
|
Magnié MN, Bermon S, Martin F, Madany-Lounis M, Suisse G, Muhammad W, Dolisi C. P300, N400, aerobic fitness, and maximal aerobic exercise. Psychophysiology 2000; 37:369-77. [PMID: 10860414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Electrophysiological effects of aerobic fitness and maximal aerobic exercise were investigated by comparing P300 and N400 before and after a maximal cycling test. Event-related potentials (ERPs) were obtained from 20 students divided into two matched groups defined by their aerobic fitness level (cyclists vs. sedentary subjects). The session of postexercise ERPs was performed immediately after body temperature and heart rate returned to preexercise values. At rest, no significant differences were observed in ERP parameters between cyclists and sedentary subjects. This finding argued against the hypothesis that ERP modifications may be directly assumed by aerobic fitness level. The postexercise session of ERPs showed a significant P300 amplitude increase and a significant P300 latency decrease in all subjects. Similarly, N400 effect increased significantly after the maximal exercise in all subjects. ERP changes were of the same magnitude in the two groups. The present study argues for a general arousing effect of maximal aerobic exercise, independently of the aerobic fitness level.
Collapse
Affiliation(s)
- M N Magnié
- Laboratoire de Physiologie, Faculté de Médecine de l'Université de Nice-Sophia Antipolis, France.
| | | | | | | | | | | | | |
Collapse
|
32
|
Raziq F, Khan MT, Muhammad W, Rashid A. Chorio angioma. J PAK MED ASSOC 1987; 37:331. [PMID: 3126327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|
33
|
Raziq F, Khan MT, Muhammad W, Rashid A. Choriocarcinoma of the fallopian tube. J PAK MED ASSOC 1987; 37:332. [PMID: 3126328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
|