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1.
J Anat ; 240(4): 669-677, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34761390

RESUMO

In 2016, two adult male sperm whales beached off of Yangkou Port in Nantong City, Jiangsu Province, China. The local government planned to preserve them as specimens, one was entrusted to Dalian Hoffen Biological Co., Ltd., and thus became the first sperm whale to be preserved by plastination. The other sperm whale was preserved in Nantong by the traditional stripping method (The skin was preserved, and then the prosthesis was filled into the skin to preserve the specimens. The material of the prosthesis was polyurethane. The outline of the animal was sculpted by suturing the skin like a bag and filling it with polyurethane). Plastination of such a large marine mammal allowed us to view the mutual adaptations of its internal structure to its specific living environment and daily habits. This sperm whale is the largest specimen in the world and this is the first time a sperm whale has been preserved using the plastination method. The plastination process also provides a method for studying the anatomy of large marine mammals for humans to understand deep-sea organisms at close contact and visual level. The plastination of this sperm whale promises to be a world class resource holding tremendous scientific, educational, and artistic value.


Assuntos
Plastinação , Cachalote , Animais , China , Masculino , Poliuretanos
2.
J Environ Manage ; 304: 114295, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35021589

RESUMO

This study investigated the impact of seasonal variation and operating conditions on recovery of potable quality water from municipal wastewater effluent using an integrated algal treatment process with a dual forward osmosis (FO)-reverse osmosis (RO) membrane system. Pilot study of the algal process treating primary effluent validated the technical viability and seasonal performance during warm weather (May to October, 25-55 °C) using an extremophilic algal strain Galdieria sulphuraria, and during cold weather (November to April, 4-17 °C) using polyculture strains of algae and bacteria. Algal effluents from both seasons were used as the feed solution for the laboratory FO-RO study. In addition, pilot-scale FO-RO experiments were conducted to compare the system performance during treatment of algal effluent and secondary effluent from the conventional treatment facility. At 90% water recovery, the FO-RO achieved over 90% overall rejection of major ions and organic matter using the bench-scale system and over 99% rejection of all contaminants in pilot-scale studies. Detailed water quality analysis indicated that the product water from the integrated system met both the primary and secondary drinking water standards. This study demonstrated that the FO-RO system can be engineered as a viable alternative to treat algal effluent and secondary effluent for potable water reuse independent of seasonal variations and operating conditions.


Assuntos
Água Potável , Purificação da Água , Membranas Artificiais , Osmose , Projetos Piloto , Águas Residuárias
3.
Bioconjug Chem ; 31(10): 2404-2412, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33001643

RESUMO

Development of nanoplatforms for targeted anticancer drug delivery for effective tumor therapy still remains challenging in the development of nanomedicine. Here, we present a facile method to formulate a LAPONITE (LAP) nanodisk-based nanosystem for anticancer drug doxorubicin (DOX) delivery to folic acid (FA) receptor-overexpressing tumors. In the current work, aminated LAP nanodisks were first prepared through silanization, then functionalized with polyethylene glycol-linked FA (PEG-FA) via 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC) chemistry, and finally employed to physically encapsulate DOX. The formed functional LAP nanodisks (for short, LM-PEG-FA) possess a high DOX loading efficiency (88.6 ± 1.2%) and present a pH-dependent release feature with a quicker DOX release under acidic pH conditions (pH 5.0) than under physiological pH conditions (pH 7.4). In vitro flow cytometry, confocal microscopic observation, and cell viability assay show that the LM-PEG-FA/DOX complexes can be specifically taken up by FAR-overexpressing human ovarian cancer cells (SK-OV-3 cells) and present a specific cancer cell therapeutic effect. Further tumor treatment results reveal that the LM-PEG-FA/DOX complexes can exert a specific therapeutic efficacy to a xenografted SK-OV-3 tumor model in vivo when compared with nontargeted LM-mPEG/DOX complexes. Therefore, the developed LM-PEG-FA nanodisks could be employed as a potential platform for targeted cancer chemotherapy.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Neoplasias Ovarianas/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Doxorrubicina/farmacocinética , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Feminino , Ácido Fólico/química , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanoestruturas/química , Neoplasias Ovarianas/patologia , Polietilenoglicóis/química
4.
J Environ Manage ; 217: 305-314, 2018 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-29614479

RESUMO

A novel and recyclable bioadsorbent (PTP) has been prepared by the cationization of persimmon tannin (PT) using polyethyleneimine (PEI) for application in the removal of the anionic dye methyl orange (MO) from aqueous solution. The physicochemical properties of the prepared PTP were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, Zeta potential measurements, Brunauer-Emmett-Teller and thermogravimetric analysis. Systematic batch adsorption experiments were carried out with pH, bioadsorbent dosage, initial MO concentration and contact time. Kinetic regression analysis indicated that the adsorption processes followed the pseudo-second order model. The equilibrium isotherm was in good fit with the Freundlich model with a maximum adsorption capacity of 225.74 mg/g. Thermodynamics data revealed that the adsorption of MO onto PTP was feasible, spontaneous and endothermic. A possible biosorption mechanism was presented where electrostatic interactions, hydrogen bonding, and π-π interactions dominated the adsorption of MO onto PTP. Moreover, the regeneration of the PTP was easily achieved and MO removal efficiency remained high (81.47%) after six cycles. The actual sewage treatment simulation was evaluated and the PTP had a good preference to adsorption MO. All these results indicated that PTP could be considered a high performance and promising candidate for the effective removal of anionic dyes from aqueous solutions.


Assuntos
Diospyros/química , Polietilenoimina/química , Poluentes Químicos da Água/química , Adsorção , Cátions , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Taninos , Termodinâmica
5.
Biomaterials ; 308: 122566, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38603824

RESUMO

Achieving sufficient bone regeneration in large segmental defects is challenging, with the structure of bone repair scaffolds and their loaded bioactive substances crucial for modulating the local osteogenic microenvironment. This study utilized digital laser processing (DLP)-based 3D printing technology to successfully fabricate high-precision methacryloylated polycaprolactone (PCLMA) bionic bone scaffold structures. Adipose-derived stem cell-engineered nanovesicles (ADSC-ENs) were uniformly and stably modified onto the bionic scaffold surface using a perfusion device, constructing a conducive microenvironment for tissue regeneration and long bone defect repair through the scaffold's structural design and the vesicles' biological functions. Scanning electron microscopy (SEM) examination of the scaffold surface confirmed the efficient loading of ADSC-ENs. The material group loaded with vesicles (PCLMA-BAS-ENs) demonstrated good cell compatibility and osteogenic potential when analyzed for the adhesion and osteogenesis of primary rabbit bone marrow mesenchymal stem cells (BMSCs) on the material surface. Tested in a 15 mm critical rabbit radial defect model, the PCLMA-BAS-ENs scaffold facilitated near-complete bone defect repair after 12 weeks. Immunofluorescence and proteomic results indicated that the PCLMA-BAS-ENs scaffold significantly improved the osteogenic microenvironment at the defect site in vivo, promoted angiogenesis, and enhanced the polarization of macrophages towards M2 phenotype, and facilitated the recruitment of BMSCs. Thus, the PCLMA-BAS-ENs scaffold was proven to significantly promote the repair of large segmental bone defects. Overall, this strategy of combining engineered vesicles with highly biomimetic scaffolds to promote large-segment bone tissue regeneration holds great potential in orthopedic and other regenerative medicine applications.


Assuntos
Regeneração Óssea , Células-Tronco Mesenquimais , Osteogênese , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais , Animais , Coelhos , Alicerces Teciduais/química , Regeneração Óssea/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Engenharia Tecidual/métodos , Biônica , Poliésteres/química , Tecido Adiposo/citologia
6.
Adv Sci (Weinh) ; 11(21): e2308381, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38447173

RESUMO

3D bioprinting techniques have enabled the fabrication of irregular large-sized tissue engineering scaffolds. However, complicated customized designs increase the medical burden. Meanwhile, the integrated printing process hinders the cellular uniform distribution and local angiogenesis. A novel approach is introduced to the construction of sizable tissue engineering grafts by employing hydrogel 3D printing for modular bioadhesion assembly, and a poly (ethylene glycol) diacrylate (PEGDA)-gelatin-dopamine (PGD) hydrogel, photosensitive and adhesive, enabling fine microcage module fabrication via DLP 3D printing is developed. The PGD hydrogel printed micocages are flexible, allowing various shapes and cell/tissue fillings for repairing diverse irregular tissue defects. In vivo experiments demonstrate robust vascularization and superior graft survival in nude mice. This assembly strategy based on scalable 3D printed hydrogel microcage module could simplify the construction of tissue with large volume and complex components, offering promise for diverse large tissue defect repairs.


Assuntos
Hidrogéis , Camundongos Nus , Impressão Tridimensional , Engenharia Tecidual , Alicerces Teciduais , Animais , Camundongos , Engenharia Tecidual/métodos , Hidrogéis/química , Alicerces Teciduais/química , Gelatina/química , Bioimpressão/métodos , Polietilenoglicóis/química , Neovascularização Fisiológica/fisiologia , Dopamina/metabolismo , Regeneração/fisiologia , Humanos
7.
Stem Cell Res Ther ; 15(1): 135, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38715130

RESUMO

BACKGROUND: Biomaterials used in bone tissue engineering must fulfill the requirements of osteoconduction, osteoinduction, and osseointegration. However, biomaterials with good osteoconductive properties face several challenges, including inadequate vascularization, limited osteoinduction and barrier ability, as well as the potential to trigger immune and inflammatory responses. Therefore, there is an urgent need to develop guided bone regeneration membranes as a crucial component of tissue engineering strategies for repairing bone defects. METHODS: The mZIF-8/PLA membrane was prepared using electrospinning technology and simulated body fluid external mineralization method. Its ability to induce biomimetic mineralization was evaluated through TEM, EDS, XRD, FT-IR, zeta potential, and wettability techniques. The biocompatibility, osteoinduction properties, and osteo-immunomodulatory effects of the mZIF-8/PLA membrane were comprehensively evaluated by examining cell behaviors of surface-seeded BMSCs and macrophages, as well as the regulation of cellular genes and protein levels using PCR and WB. In vivo, the mZIF-8/PLA membrane's potential to promote bone regeneration and angiogenesis was assessed through Micro-CT and immunohistochemical staining. RESULTS: The mineralized deposition enhances hydrophilicity and cell compatibility of mZIF-8/PLA membrane. mZIF-8/PLA membrane promotes up-regulation of osteogenesis and angiogenesis related factors in BMSCs. Moreover, it induces the polarization of macrophages towards the M2 phenotype and modulates the local immune microenvironment. After 4-weeks of implantation, the mZIF-8/PLA membrane successfully bridges critical bone defects and almost completely repairs the defect area after 12-weeks, while significantly improving the strength and vascularization of new bone. CONCLUSIONS: The mZIF-8/PLA membrane with dual osteoconductive and immunomodulatory abilities could pave new research paths for bone tissue engineering.


Assuntos
Regeneração Óssea , Regeneração Óssea/efeitos dos fármacos , Animais , Osteogênese/efeitos dos fármacos , Engenharia Tecidual/métodos , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química , Camundongos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/citologia , Membranas Artificiais , Regeneração Tecidual Guiada/métodos , Alicerces Teciduais/química , Poliésteres/química , Poliésteres/farmacologia , Ratos
8.
ACS Nano ; 17(9): 7953-7978, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37071059

RESUMO

Hydrogels, as one of the most feasible soft biomaterials, have gained considerable attention in therapeutic applications by virtue of their tunable properties including superior patient compliance, good biocompatibility and biodegradation, and high cargo-loading efficiency. However, hydrogel application is still limited by some challenges like inefficient encapsulation, easy leakage of loaded cargoes, and the lack of controllability. Recently, nanoarchitecture-integrated hydrogel systems were found to be therapeutics with optimized properties, extending their bioapplication. In this review, we briefly presented the category of hydrogels according to their synthetic materials and further discussed the advantages in bioapplication. Additionally, various applications of nanoarchitecture hybrid hydrogels in biomedical engineering are systematically summarized, including cancer therapy, wound healing, cardiac repair, bone regeneration, diabetes therapy, and obesity therapy. Last, the current challenges, limitations, and future perspectives in the future development of nanoarchitecture-integrated flexible hydrogels are addressed.


Assuntos
Hidrogéis , Engenharia Tecidual , Humanos , Hidrogéis/uso terapêutico , Materiais Biocompatíveis/farmacologia , Cicatrização , Regeneração Óssea
9.
Chemosphere ; 240: 124883, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31726606

RESUMO

A coupled algal-osmosis membrane treatment system was studied for recovering potable-quality water from municipal primary effluent. The core components of the system included a mixotrophic algal process for removal of biochemical oxygen demand (BOD) and nutrients, followed by a hybrid forward osmosis (FO)-reverse osmosis (RO) system for separation of biomass from the algal effluent and production of potable-quality water. Field experiments demonstrated consistent performance of the algal system to meet surface discharge standards for BOD and nutrients within a fed-batch processing time of 2-3 days. The hybrid FO-RO system reached water productivity of 1.57 L/m2-h in FO using seawater as draw solution; and permeate flux of 3.50 L/m2-h in brackish water RO (BWRO) and 2.07 L/m2-h in seawater RO (SWRO) at 2068 KPa. The coupled algal-membrane system achieved complete removal of ammonia, fluoride, and phosphate; over 90% removal of calcium, sulfate, and organic carbon; and 86-89% removal of potassium and magnesium. Broadband characterization using high resolution mass spectrometry revealed extensive removal of organic compounds, particularly wastewater surfactants upon algal treatment. This study demonstrated long-term performance of the FO system at water recovery of 90% and with membrane cleaning by NaOH solution.


Assuntos
Reatores Biológicos/microbiologia , Água Potável/análise , Membranas Artificiais , Rodófitas/crescimento & desenvolvimento , Purificação da Água/métodos , Filtração/métodos , Compostos Orgânicos/análise , Osmose , Águas Salinas/química , Água do Mar/química , Águas Residuárias/química , Poluentes Químicos da Água/análise
10.
Nanoscale ; 8(10): 5567-77, 2016 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-26890691

RESUMO

Development of new long-circulating contrast agents for computed tomography (CT) imaging of different biological systems still remains a great challenge. Here, we report the design and synthesis of branched polyethyleneimine (PEI)-stabilized gold nanoparticles (Au PSNPs) modified with polyethylene glycol (PEG) for blood pool, lymph node, and tumor CT imaging. In this study, thiolated PEI was first synthesized and used as a stabilizing agent to form AuNPs. The formed Au PSNPs were then grafted with PEG monomethyl ether via PEI amine-enabled conjugation chemistry, followed by acetylation of the remaining PEI surface amines. The formed PEGylated Au PSNPs were characterized via different methods. We show that the PEGylated Au PSNPs with an Au core size of 5.1 nm have a relatively long half-decay time (7.8 h), and display a better X-ray attenuation property than conventionally used iodine-based CT contrast agents (e.g., Omnipaque), and are hemocompatible and cytocompatible in a given concentration range. These properties of the Au PSNPs afford their uses as a contrast agent for effective CT imaging of the blood pool and major organs of rats, lymph node of rabbits, and the xenografted tumor model of mice. Importantly, the PEGylated Au PSNPs could be excreted out of the body with time and also showed excellent in vivo stability. These findings suggest that the formed PEGylated Au PSNPs may be used as a promising contrast agent for CT imaging of different biological systems.


Assuntos
Meios de Contraste/química , Linfonodos/diagnóstico por imagem , Nanopartículas Metálicas/química , Neoplasias/diagnóstico por imagem , Polietilenoglicóis/química , Polietilenoimina/química , Tomografia Computadorizada por Raios X , Animais , Materiais Biocompatíveis/química , Linhagem Celular , Sobrevivência Celular , Coloides/química , Ouro/química , Hemólise , Humanos , Iodo/química , Linfonodos/patologia , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Nanotecnologia , Transplante de Neoplasias , Coelhos , Ratos , Ratos Sprague-Dawley , Compostos de Sulfidrila/química , Raios X
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