1
|
Ganesan M, Muthaiah C, Wadaan MA, Kumar M, Yanto DHY, Kumar S, Selvankumar T, Arulraj A, Mangalaraja RV, Suganthi S. Synthesis and characterization of fluorinated graphene oxide nanosheets derived from Lissachatina fulica snail mucus and their biomedical applications. LUMINESCENCE 2024; 39:e4875. [PMID: 39228310 DOI: 10.1002/bio.4875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Revised: 07/29/2024] [Accepted: 08/18/2024] [Indexed: 09/05/2024]
Abstract
The modern nanomedicine incorporates the multimodal treatments into a single formulation, offering innovative cancer therapy options. Nanosheets function as carriers, altering the solubility, biodistribution, and effectiveness of medicinal compounds, resulting in more efficient cancer treatments and reduced side effects. The non-toxic nature of fluorinated graphene oxide (FGO) nanosheets and their potential applications in medication delivery, medical diagnostics, and biomedicine distinguish them from others. Leveraging the unique properties of Lissachatina fulica snail mucus (LfSM), FGO nanosheets were developed to reveal the novel characteristics. Consequently, LfSM was utilized to create non-toxic, environmentally friendly, and long-lasting FGO nanosheets. Ultraviolet-visible (UV-vis) spectroscopy revealed a prominent absorbance peak at 235 nm. The characterization of the synthesized FGO nanosheets involved X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HR-TEM), and atomic force microscopy (AFM) analyses. The antimicrobial activity data demonstrated a broad spectrum of antibacterial effects against Escherichia coli, Bacillus subtilis, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The cytotoxicity efficacy of LfSM-FGO nanosheets against pancreatic cancer cell line (PANC1) showed promising results at low concentrations. The study suggests that FGO nanosheets made from LfSM could serve as alternate factors for in biomedical applications in the future.
Collapse
Affiliation(s)
| | - Chandran Muthaiah
- Department of Zoology, Thiruvalluvar University, Vellore, Tamil Nadu, India
| | - Mohammad Ahmad Wadaan
- Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia
| | - Manimaran Kumar
- Research Center for Applied Microbiology, National Research and Innovation Agency (BRIN), Cibinong, Republic of Indonesia
| | - Dede Heri Yuli Yanto
- Research Center for Applied Microbiology, National Research and Innovation Agency (BRIN), Cibinong, Republic of Indonesia
| | - Selvaraj Kumar
- State Key Laboratory of Fire Science, University of Science and Technology of China, Hefei, Anhui, China
| | - Thangasamy Selvankumar
- Biomaterials Research Unit, Center for Global Health Research, Saveetha Medical College & Hospital, Saveetha Institute of Medical and Technical Sciences (SIMATS), Chennai, Tamil Nadu, India
| | - Arunachalam Arulraj
- Departamento de Electricidad, Facultad de Ingeniería, Universidad Tecnológica Metropolitana (UTEM), Ñuñoa, Santiago, Chile
| | - Ramalinga Viswanathan Mangalaraja
- Faculty of Engineering and Sciences, Universidad Adolfo Ibáñez, Peñalolén, Santiago, Chile
- Vicerrectoría de Investigación e Innovación, Universidad Arturo Prat, Iquique, Chile
| | - Sanjeevamuthu Suganthi
- Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, Tamil Nadu, India
| |
Collapse
|
2
|
Wang Q, Serda M, Li Q, Sun T. Recent Advancements on Self-Immolative System Based on Dynamic Covalent Bonds for Delivering Heterogeneous Payloads. Adv Healthc Mater 2023; 12:e2300138. [PMID: 36943096 DOI: 10.1002/adhm.202300138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 03/10/2023] [Indexed: 03/23/2023]
Abstract
The precisely spatial-temporal delivery of heterogeneous payloads from a single system with the same pulse is in great demand in realizing versatile and synergistic functions. Very few molecular architectures can satisfy the strict requirements of dual-release translated from single triggers, while the self-immolative systems based on dynamic covalent bonds represent the "state-of-art" of ultimate solution strategy. Embedding heterogeneous payloads symmetrically onto the self-immolative backbone with dynamic covalent bonds as the trigger, can respond to the quasi-bio-orthogonal hallmarks which are higher at the disease's microenvironment to simultaneously yield the heterogeneous payloads (drug A/drug B or drug/reporter). In this review, the modular design principles are concentrated to illustrate the rules in tailoring useful structures, then the rational applications are enumerated on the aspects of drug codelivery and visualized drug-delivery. This review, hopefully, can give the general readers a comprehensive understanding of the self-immolative systems based on dynamic covalent bonds for delivering heterogeneous payloads.
Collapse
Affiliation(s)
- Qingbing Wang
- Department of Interventional Radiology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, 197 Rui Jin Er Road, Shanghai, 200025, P. R. China
- Key Laboratory of Smart Drug Delivery Ministry of Education, Department of Pharmaceutics, School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai, 201203, P. R. China
| | - Maciej Serda
- Institute of Chemistry, University of Silesia in Katowice, Katowice, 40-006, Poland
| | - Quan Li
- School of Chinese Materia Medica, Tianjin University of Traditional Chinese Medicine, 10 Boyanghu Road, Tianjin, 301617, P. R. China
- College of Chemistry and Chemical Engineering, Hubei University, 368 Youyidadao Avenue, Wuhan, 430062, P. R. China
| | - Tao Sun
- Key Laboratory of Smart Drug Delivery Ministry of Education, Department of Pharmaceutics, School of Pharmacy, Fudan University, 826 Zhangheng Road, Shanghai, 201203, P. R. China
| |
Collapse
|
3
|
Engineering and surface modification of carbon quantum dots for cancer bioimaging. INORG CHEM COMMUN 2023. [DOI: 10.1016/j.inoche.2023.110433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
|
4
|
Deb Roy JS, Chowdhury D, Sanfui MH, Hassan N, Mahapatra M, Ghosh NN, Majumdar S, Chattopadhyay PK, Roy S, Singha NR. Ratiometric pH Sensing, Photophysics, and Cell Imaging of Nonaromatic Light-Emitting Polymers. ACS APPLIED BIO MATERIALS 2022; 5:2990-3005. [PMID: 35579235 DOI: 10.1021/acsabm.2c00297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Here, four nontraditional fluorescent polymers (NTFPs) of varying N,N-dimethyl-2-propenamide (DMPA) and butyl prop-2-enoate (BPE) mole ratios, i.e., 2:1 (NTFP1), 4:1 (NTFP2), 8:1 (NTFP3), and 16:1 (NTFP4), are prepared via random polymerization in water. The maximum fluorescence enhancement of NTFP3 makes it suitable for ratiometric pH sensing, Cu(II) sensing, and pH-dependent cell imaging of Madin-Darby canine kidney (MDCK) cells. The oxygen donor functionalities of NTFP3 involved in binding and sensing with Cu(II) ions are studied by absorption, emission, electron paramagnetic resonance, Fourier transform infrared (FTIR), and O1s/Cu2p X-ray photoelectron spectroscopies (XPS). The spectral responses of the ratiometric pH sensor within 1.5-11.5 confirm 22 and 44 nm red shifts in absorption and ratiometric emission, respectively. The striking color changes from blue (436 nm) to green (480 nm) via an increase in pH are thought to be the stabilization of the charged canonical form of tertiary amide, i.e., -C(O-)═N+(CH3)2, realized from the changes in the absorption/fluorescence spectra and XPS/FTIR analyses. The through-space n-π* interactions in the NTFP3 aggregate, N-branching-associated rigidity, and nonconventional intramolecular hydrogen bondings of adjacent NTFP3 moieties in the NTFP3 aggregate contribute to aggregation-enhanced emissions (AEEs). Here, structures of NTFP3, NTFP3 aggregate, and Cu(II)-NTFP3; absorption; n-π* interactions; hydrogen bondings; AEEs; and binding with Cu(II) are ascertained by density functional theory, time-dependent density functional theory, and reduced density gradient calculations. The excellent limits of detection and Stern-Volmer constants of NTFP3 are 2.24 nM/0.14234 ppb and 4.26 × 103 M-1 at pH = 6.5 and 0.95 nM/0.06037 ppb and 4.90 × 103 M-1 at pH = 8.0, respectively. Additionally, the Stokes shift and binding energy of NTFP3 are 13,636 cm-1/1.69 eV and -4.64 eV, respectively. The pH-dependent MDCK cell imaging ability of noncytotoxic NTFP3 is supported via fluorescence imaging and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.
Collapse
Affiliation(s)
- Joy Sankar Deb Roy
- Advanced Polymer Laboratory, Department of Polymer Science and Technology, Government College of Engineering and Leather Technology (Post Graduate), Maulana Abul Kalam Azad University of Technology, Salt Lake City, Kolkata, West Bengal 700106, India
| | - Deepak Chowdhury
- Advanced Polymer Laboratory, Department of Polymer Science and Technology, Government College of Engineering and Leather Technology (Post Graduate), Maulana Abul Kalam Azad University of Technology, Salt Lake City, Kolkata, West Bengal 700106, India
| | - Md Hussain Sanfui
- Advanced Polymer Laboratory, Department of Polymer Science and Technology, Government College of Engineering and Leather Technology (Post Graduate), Maulana Abul Kalam Azad University of Technology, Salt Lake City, Kolkata, West Bengal 700106, India
| | - Nadira Hassan
- Advanced Polymer Laboratory, Department of Polymer Science and Technology, Government College of Engineering and Leather Technology (Post Graduate), Maulana Abul Kalam Azad University of Technology, Salt Lake City, Kolkata, West Bengal 700106, India
| | - Manas Mahapatra
- Advanced Polymer Laboratory, Department of Polymer Science and Technology, Government College of Engineering and Leather Technology (Post Graduate), Maulana Abul Kalam Azad University of Technology, Salt Lake City, Kolkata, West Bengal 700106, India
| | - Narendra Nath Ghosh
- Department of Chemistry, University of Gour Banga, Mokdumpur, Malda, West Bengal 732103, India
| | - Swapan Majumdar
- Department of Chemistry, Tripura University, Suryamaninagar, Agartala 799022, India
| | - Pijush Kanti Chattopadhyay
- Department of Leather Technology, Government College of Engineering and Leather Technology (Post Graduate), Maulana Abul Kalam Azad University of Technology, Salt Lake City, Kolkata, West Bengal 700106, India
| | - Subhasis Roy
- Department of Chemical Engineering, University of Calcutta, 92, A.P.C. Road, Kolkata, West Bengal 700009, India
| | - Nayan Ranjan Singha
- Advanced Polymer Laboratory, Department of Polymer Science and Technology, Government College of Engineering and Leather Technology (Post Graduate), Maulana Abul Kalam Azad University of Technology, Salt Lake City, Kolkata, West Bengal 700106, India
| |
Collapse
|
5
|
Cai R, Xiao L, Liu M, Du F, Wang Z. Recent Advances in Functional Carbon Quantum Dots for Antitumour. Int J Nanomedicine 2021; 16:7195-7229. [PMID: 34720582 PMCID: PMC8550800 DOI: 10.2147/ijn.s334012] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 09/23/2021] [Indexed: 12/20/2022] Open
Abstract
Carbon quantum dots (CQDs) are an emerging class of quasi-zero-dimensional photoluminescent nanomaterials with particle sizes less than 10 nm. Owing to their favourable water dispersion, strong chemical inertia, stable optical performance, and good biocompatibility, CQDs have become prominent in biomedical fields. CQDs can be fabricated by “top-down” and “bottom-up” methods, both of which involve oxidation, carbonization, pyrolysis and polymerization. The functions of CQDs include biological imaging, biosensing, drug delivery, gene carrying, antimicrobial performance, photothermal ablation and so on, which enable them to be utilized in antitumour applications. The purpose of this review is to summarize the research progress of CQDs in antitumour applications from preparation and characterization to application prospects. Furthermore, the challenges and opportunities of CQDs are discussed along with future perspectives for precise individual therapy of tumours.
Collapse
Affiliation(s)
- Rong Cai
- Central Laboratory, Zhangjiagang TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, Jiangsu, 215600, People's Republic of China
| | - Long Xiao
- Central Laboratory, Zhangjiagang TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, Jiangsu, 215600, People's Republic of China
| | - Meixiu Liu
- Central Laboratory, Zhangjiagang TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, Jiangsu, 215600, People's Republic of China
| | - Fengyi Du
- School of Medicine, Zhenjiang, Jiangsu, 212013, People's Republic of China
| | - Zhirong Wang
- Central Laboratory, Zhangjiagang TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Suzhou, Jiangsu, 215600, People's Republic of China
| |
Collapse
|
6
|
Wang B, Song H, Qu X, Chang J, Yang B, Lu S. Carbon dots as a new class of nanomedicines: Opportunities and challenges. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2021.214010] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
|
7
|
Hayashida O, Shibata K. Stimuli-Responsive Supramolecular Coaggregation and Disaggregation of Host-Guest Conjugates Having a Disulfide Linkage. J Org Chem 2020; 85:5493-5502. [PMID: 32233372 DOI: 10.1021/acs.joc.0c00237] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Water-soluble cationic and anionic cyclophanes (1a and 2a, respectively) having a dabsyl group with a cleavable disulfide linkage were synthesized as a host-guest conjugate covalently bound with both host and guest components. Self-inclusion phenomena but not self-aggregation behaviors were observed for each cyclophane in aqueous media. Each cyclophane includes its own dabsyl moiety (guest component) in its macrocyclic cavity (host component) through hydrophobic interaction. When 1 equiv. of cationic 1a was added to an aqueous solution of anionic 2a, however, supramolecular coaggregates formed spontaneously through host-guest complexation. As regard the supramolecular coaggregates, the existence of larger particles was confirmed by DLS measurements and TEM observation. The hydrophobic interaction between the dabsyl moiety and macrocyclic cavity and electrostatic interactions between 1a and 2a play important roles in the supramolecular coaggregate formation. Each cyclophane having a cleavable disulfide linkage was easily transformed to the corresponding thiols by reducing reagents such as DTT, which was confirmed by MALDI-TOF MS. Disaggregation of the supramolecular coaggregates composed of 1a and 2a was successfully performed upon addition of DTT, with release of the thiol derivative of dabsyl. Such disaggregation of the coaggregates was also conducted by other external stimuli such as salts and competitive guests.
Collapse
Affiliation(s)
- Osamu Hayashida
- Department of Chemistry, Faculty of Science, Fukuoka University, Nanakuma 8-19-1, Fukuoka 814-0180, Japan
| | - Kana Shibata
- Department of Chemistry, Faculty of Science, Fukuoka University, Nanakuma 8-19-1, Fukuoka 814-0180, Japan
| |
Collapse
|
8
|
Ghiasi B, Mehdipour G, Safari N, Behboudi H, Hashemi M, Omidi M, Sefidbakht Y, Yadegari A, Hamblin MR. Theranostic applications of stimulus-responsive systems based on carbon dots. INT J POLYM MATER PO 2019; 70:117-130. [PMID: 33967355 PMCID: PMC8101985 DOI: 10.1080/00914037.2019.1695207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 11/09/2019] [Indexed: 12/29/2022]
Abstract
Over recent years, many different nanoparticle-based drug delivery systems (NDDSs) have been developed. Recently the development of stimulus-responsive NDDSs has come into sharper focus. Carbon dots (CDs) possess outstanding features such as useful optical properties, good biocompatibility, and the ability for easy surface modification. Appropriate surface modification can allow these NDDSs to respond to various chemical or physical stimuli that are characteristic of their target cells or tissue (frequently malignant cells or tumors). The present review covers recent developments of CDs in NDDSs with a particular focus on internal stimulus response capability that allows simultaneous imaging and therapeutic delivery (theranostics). Relevant stimuli associated with tumor cells and tumors include pH levels, redox potential, and different enzymatic activities can be used to activate the CDs at the desired sites.
Collapse
Affiliation(s)
- Behrad Ghiasi
- Protein Research Center, Shahid Beheshti University, Tehran, Iran
| | - Golnaz Mehdipour
- Protein Research Center, Shahid Beheshti University, Tehran, Iran
| | - Nooshin Safari
- Protein Research Center, Shahid Beheshti University, Tehran, Iran
| | | | - Mohadeseh Hashemi
- Protein Research Center, Shahid Beheshti University, Tehran, Iran
- Biomedical Engineering Department, The University of Texas at Austin, Austin, TX, USA
| | - Meisam Omidi
- School of Dentistry, Marquette University, Milwaukee, WI, USA
| | - Yahya Sefidbakht
- Protein Research Center, Shahid Beheshti University, Tehran, Iran
| | - Amir Yadegari
- School of Dentistry, Marquette University, Milwaukee, WI, USA
| | - Michael R. Hamblin
- Massachusetts General Hospital, Wellman Center for Photomedicine, Boston, MA, USA
- Department of Dermatology, Harvard Medical School, Boston, MA, USA
- Laser Research Centre, Faculty of Health Science, University of Johannesburg, Doornfontein, South Africa
| |
Collapse
|
9
|
Revisiting fluorescent carbon nanodots for environmental, biomedical applications and puzzle about fluorophore impurities. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.nanoso.2019.100391] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
10
|
Cui Y, Zhang R, Yang L, Lv S. Self-carried AIE nanoparticles for in vitro non-invasive long-term imaging. CHINESE CHEM LETT 2019. [DOI: 10.1016/j.cclet.2018.10.017] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
11
|
Dual-emission carbon dots as biocompatible nanocarrier for in vitro/in vivo cell microenvironment ratiometric pH sensing in broad range. JOURNAL OF THE IRANIAN CHEMICAL SOCIETY 2019. [DOI: 10.1007/s13738-019-01678-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
12
|
Lu H, Yu C, Quan S, Xu S. A novel dual response ratiometric fluorescent probe for the determination of H2O2 and glucose via etching of silver nanoparticles. Analyst 2019; 144:1153-1158. [DOI: 10.1039/c8an02019a] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Based on the inner filter effect and charge transfer, a dual response ratiometric fluorescence assay for sensing H2O2 and glucose was proposed based on etching of Ag NPs.
Collapse
Affiliation(s)
- Hongzhi Lu
- School of Chemistry and Chemical Engineering
- Linyi University
- Linyi 276005
- China
| | - Chunwei Yu
- Laboratory of Environmental Monitoring
- School of Tropical and Laboratory Medicine
- Hainan Medical University
- Haikou 571101
- China
| | - Shuai Quan
- School of Materials Science and Engineering
- Linyi University
- Linyi 276005
- China
| | - Shoufang Xu
- School of Materials Science and Engineering
- Linyi University
- Linyi 276005
- China
| |
Collapse
|
13
|
Zhang J, Xu B, Tian W, Xie Z. Tailoring the morphology of AIEgen fluorescent nanoparticles for optimal cellular uptake and imaging efficacy. Chem Sci 2018; 9:2620-2627. [PMID: 29675254 PMCID: PMC5892346 DOI: 10.1039/c7sc05130a] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Accepted: 01/15/2018] [Indexed: 12/16/2022] Open
Abstract
The rational design of robust fluorescent organic materials for long-term cell tracing is still challenging, and aggregation-caused quenching of emission is a big limitation of this strategy. Organic dyes with aggregation-induced emission (AIE) can effectively address this problem. Herein, AIEgen-containing nanoparticles, with different morphologies and emission, were prepared by assembling amphiphilic copolymers with an AIEgen. We compared the physical and chemical properties of rod-like and spherical nanoparticles, particularly investigating the effects of the shape on internalization and the imaging effect. The formulated nanoparticles exhibit advantageous features, such as a large Stokes shift, robust stability in physiological conditions, strong fluorescent emission, and photobleaching resistance. Interestingly, the rod-like nanoparticles were internalized more efficiently than their spherical counterparts, and their strong green fluorescence can still be clearly observed even after 15 days in vitro and in vivo. This work demonstrates the great potential of regulating the morphology of nanoparticles to obtain an ideal biological function.
Collapse
Affiliation(s)
- Jianxu Zhang
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry , Chinese Academy of Sciences , 5625 Renmin Street , Changchun , Jilin 130022 , P. R. China . .,University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | - Bin Xu
- State Key Laboratory of Supramolecular Structure and Materials , Jilin University , Changchun , 130012 Jilin , P. R. China .
| | - Wenjing Tian
- State Key Laboratory of Supramolecular Structure and Materials , Jilin University , Changchun , 130012 Jilin , P. R. China .
| | - Zhigang Xie
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry , Chinese Academy of Sciences , 5625 Renmin Street , Changchun , Jilin 130022 , P. R. China .
| |
Collapse
|