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1.
Chem Biol Interact ; 351: 109738, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34740598

RESUMO

The rapid spread of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) that causes coronavirus disease 2019 (COVID-19), has had a dramatic negative impact on public health and economies worldwide. Recent studies on COVID-19 complications and mortality rates suggest that there is a higher prevalence in cardiovascular diseases (CVD) patients. Past investigations on the associations between pre-existing CVDs and susceptibility to coronavirus infections including SARS-CoV and the Middle East Respiratory Syndrome coronavirus (MERS-CoV), have demonstrated similar results. However, the underlying mechanisms are poorly understood. This has impeded adequate risk stratification and treatment strategies for CVD patients with SARS-CoV-2 infections. Generally, dysregulation of the expression of angiotensin-converting enzyme (ACE) and the counter regulator, angiotensin-converting enzyme 2 (ACE2) is a hallmark of cardiovascular risk and CVD. ACE2 is the main host receptor for SARS-CoV-2. Although further studies are required, dysfunction of ACE2 after virus binding and dysregulation of the renin-angiotensin-aldosterone system (RAAS) signaling may worsen the outcomes of people affected by COVID-19 and with preexisting CVD. Here, we review the current knowledge and outline the gaps related to the relationship between CVD and COVID-19 with a focus on the RAAS. Improved understanding of the mechanisms regulating viral entry and the role of RAAS may direct future research with the potential to improve the prevention and management of COVID-19.

2.
Stem Cell Res ; 56: 102552, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34634760

RESUMO

Alzheimer's disease (AD) is the major cause of dementia worldwide. Early-onset familial AD accounts for about 0.5% of all AD and is caused by single major gene mutations and autosomal dominant inheritance. An N141I missense mutation is associated with a significant increase in basal cell death and apoptosis. In this work we generated hiPSC from skin fibroblasts obtained from an AD patient carrying a N141I missense mutation in PSEN2. The generated iPSC colonies grew and were characterized by pluripotency marker staining; the N141I missense mutation was corrected using genome editing technology.


Assuntos
Doença de Alzheimer , Células-Tronco Pluripotentes Induzidas , Doença de Alzheimer/genética , Edição de Genes , Humanos , Mutação , Mutação de Sentido Incorreto , Presenilina-1 , Presenilina-2/genética
3.
J Adv Res ; 33: 227-239, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34603792

RESUMO

Background: Because enzymes can control several metabolic pathways and regulate the production of free radicals, their simultaneous use with nanoplatforms showing protective and combinational properties is of great interest in the development of therapeutic nano-based platforms. However, enzyme immobilization on nanomaterials is not straightforward due to the toxic and unpredictable properties of nanoparticles in medical practice. Aim of review: In fact, because of the ability to load enzymes on nano-based supports and increase their renewability, scientific groups have been tempted to create potential therapeutic enzymes in this field. Therefore, this study not only pays attention to the therapeutic and diagnostic applications of diseases by enzyme-nanoparticle (NP) bio-conjugate (abbreviated as: ENB), but also considers the importance of nanoplatforms used based on their toxicity, ease of application and lack of significant adverse effects on loaded enzymes. In the following, based on the published reports, we explained that the immobilization of enzymes on polymers, inorganic metal oxide and hybrid compounds provide hopes for potential use of ENBs in medical activities. Then, the use of ENBs in bioassay activities such as paper-based or wearing biosensors and lab-on-chip/microfluidic biosensors were evaluated. Finally, this review addresses the current challenges and future perspective of ENBs in biomedical applications. Key scientific concepts of review: This literature may provide useful information regarding the application of ENBs in biosensing and therapeutic platforms.

4.
Colloids Surf B Biointerfaces ; 208: 112105, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34536674

RESUMO

Diabetic foot ulcers (DFUs) that are not effectively treated could lead to partial or complete lower limb amputations. The lack of connective tissue growth factor (CTGF) and insulin-like growth factor (IGF-I) in DFUs results in limited matrix deposition and poor tissue repair. To enhance growth factor (GF) availability in DFUs, heparin (HN)-mimetic alginate sulfate/polycaprolactone (AlgSulf/PCL) double emulsion nanoparticles (NPs) with high affinity and sustained release of CTGF and IGF-I were synthesized. The NPs size, encapsulation efficiency (EE), cytotoxicity, cellular uptake and wound healing capacity in immortalized primary human adult epidermal cells (HaCaT) were assessed. The sonication time and amplitude used for NPs synthesis enabled the production of particles with a minimum of 236 ± 25 nm diameter. Treatment of HaCaT cells with up to 50 µg mL-1 of NPs showed no cytotoxic effects after 72 h. The highest bovine serum albumin EE (94.6 %, P = 0.028) and lowest burst release were attained with AlgSulf/PCL. Moreover, cells treated with AlgSulf/CTGF (250 ng mL-1) exhibited the most rapid wound closure compared to controls while maintaining fibronectin synthesis. Double-emulsion NPs based on HN-mimetic AlgSulf represent a novel approach which can significantly enhance diabetic wound healing and can be expanded for applications requiring the delivery of other HN-binding GFs.


Assuntos
Pé Diabético , Nanopartículas , Alginatos , Emulsões , Heparina , Humanos , Poliésteres , Sulfatos , Cicatrização
5.
J Control Release ; 338: 341-357, 2021 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-34428480

RESUMO

Microneedle arrays have recently received much attention as cancer detection and treatment platforms, because invasive injections and detection of the biopsy are not needed, and drug metabolism by the liver, as well as adverse effects of systemic drug administration, are diminished. Microneedles have been used for diagnosis, vaccination, and in targeted drug delivery of breast cancer. In this review, we summarize the recent progress in diagnosis and targeted drug delivery for breast cancer treatment, using microneedle arrays to deliver active molecules through the skin. The results not only suggest that health and well-being of patients are improved, but also that microneedle arrays can deliver anticancer compounds in a relatively noninvasive manner, based on body weight, breast tumor size, and circulation time of the drug. Moreover, microneedles could allow simultaneous loading of multiple drugs and enable controlled release, thus effectively optimizing or preventing drug-drug interactions. This review is designed to encourage the use of microneedles for diagnosis and treatment of breast cancer, by describing general properties of microneedles, materials used for construction, mechanism of action, and principal benefits. Ongoing challenges and future perspectives for the application of microneedle array systems in breast cancer detection and treatment are highlighted.


Assuntos
Neoplasias da Mama , Administração Cutânea , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Feminino , Humanos , Microinjeções , Agulhas , Pele/metabolismo
6.
Biotechnol J ; 16(10): e2100044, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34313388

RESUMO

BACKGROUND: The development of anti-cancer drugs with the ability to inhibit brain metastasis through the blood-brain barrier (BBB) is substantially limited due to the lack of reliable in vitro models. MAIN METHODS: In this study, the Geltrex-based Transwell and microfluidic BBB models were applied to screen the effect of ß-boswellic acid (ß-BA) on the metastasis of MDA-MB-231 cells through the BBB in static and dynamic conditions, respectively. MAJOR RESULTS: The toxicity assay revealed that ß-BA deteriorates MDA-MB-231 cells, while ß-BA had no detectable toxic effects on human umbilical vein endothelial cells (HUVECs) and astrocytes. Trans-endothelial electrical resistance evaluation showed sustainable barrier integrity upon treatment with ß-BA. Vimentin expression in HUVECs, evaluated using western blot, confirmed superior barrier integrity in the presence of ß-BA. The obtained results were confirmed using an invasion study with a cell tracker and a scanning electron microscope. ß-BA significantly inhibited metastasis by 85%, while cisplatin (Cis), a positive control, inhibited cancer cell migration by 12% under static conditions. Upon applying a dynamic BBB model, it was revealed that ß-BA-mediated metastasis inhibition was significantly higher than that mediated by Cis. CONCLUSIONS AND IMPLICATIONS:  In summary, the current study proved the anti-metastatic potential of ß-BA in both static and dynamic BBB models.


Assuntos
Barreira Hematoencefálica , Triterpenos , Células Endoteliais da Veia Umbilical Humana , Humanos , Microfluídica , Triterpenos/farmacologia
7.
Nanomaterials (Basel) ; 11(5)2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067844

RESUMO

Bone tissue engineering is an advanced field for treatment of fractured bones to restore/regulate biological functions. Biopolymeric/bioceramic-based hybrid nanocomposite scaffolds are potential biomaterials for bone tissue because of biodegradable and biocompatible characteristics. We report synthesis of nanocomposite based on acrylic acid (AAc)/guar gum (GG), nano-hydroxyapatite (HAp NPs), titanium nanoparticles (TiO2 NPs), and optimum graphene oxide (GO) amount via free radical polymerization method. Porous scaffolds were fabricated through freeze-drying technique and coated with silver sulphadiazine. Different techniques were used to investigate functional group, crystal structural properties, morphology/elemental properties, porosity, and mechanical properties of fabricated scaffolds. Results show that increasing amount of TiO2 in combination with optimized GO has improved physicochemical and microstructural properties, mechanical properties (compressive strength (2.96 to 13.31 MPa) and Young's modulus (39.56 to 300.81 MPa)), and porous properties (pore size (256.11 to 107.42 µm) and porosity (79.97 to 44.32%)). After 150 min, silver sulfadiazine release was found to be ~94.1%. In vitro assay of scaffolds also exhibited promising results against mouse pre-osteoblast (MC3T3-E1) cell lines. Hence, these fabricated scaffolds would be potential biomaterials for bone tissue engineering in biomedical engineering.

8.
Cancer Med ; 10(15): 5019-5030, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34145792

RESUMO

Glioblastoma multiforme (GBM) is one of the deadliest brain tumors with an unfavorable prognosis and overall survival of approximately 20 months following diagnosis. The current treatment for GBM includes surgical resections and chemo- and radiotherapeutic modalities, which are not effective. CAR-T immunotherapy has been proven effective for CD19-positive blood malignancies, and the application of CAR-T cell therapy for solid tumors including GBM offers great hope for this aggressive tumor which has a limited response to current treatments. CAR-T technology depends on the use of patient-specific T cells genetically engineered to express specific tumor-associated antigens (TAAs). Interaction of CAR-T cells with tumor cells triggers the destruction/elimination of these cells by the induction of cytotoxicity and the release of different cytokines. Despite the great promise of CAR-T cell-based therapy several challenges exist. These include the heterogeneity of GBM cancer cells, aberrant various signaling pathways involved in tumor progression, antigen escape, the hostile inhibitory GBM microenvironment, T cell dysfunction, blood-brain barrier, and defective antigen presentation. All need to be addressed before full application at the clinical level can begin. Herein we provide a focused review of the rationale for the use of different types of CAR-T cells (including FcγRs), the different GBM-associated antigens, the challenges still facing CAR-T-based therapy, and means to overcome such challenges. Finally, we enumerate currently completed and ongoing clinical trials, highlighting the different ways such trials are designed to overcome specific problems. Exploitation of the full potential of CAR-T cell therapy for GBM depends on their solution.

9.
Adv Colloid Interface Sci ; 294: 102457, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34144344

RESUMO

The application of nanostructured materials in medicine is a rapidly evolving area of research that includes both the diagnosis and treatment of various diseases. Metals, metal oxides and carbon-based nanomaterials have shown much promise in medical technological advancements due to their tunable physical, chemical and biological properties. The nanoscale properties, especially the size, shape, surface chemistry and stability makes them highly desirable for diagnosing and treating various diseases, including cancers. Major applications of nanomaterials in cancer diagnosis include in vivo bioimaging and molecular marker detection, mainly as image contrast agents using modalities such as radio, magnetic resonance, and ultrasound imaging. When a suitable targeting ligand is attached on the nanomaterial surface, it can help pinpoint the disease site during imaging. The application of nanostructured materials in cancer diagnosis can help in the early detection, treatment and patient follow-up . This review aims to gather and present the information regarding the application of nanotechnology in cancer diagnosis. We also discuss the challenges and prospects regarding the application of nanomaterials as cancer diagnostic tools.


Assuntos
Nanoestruturas , Neoplasias , Diagnóstico por Imagem , Humanos , Metais , Nanotecnologia , Neoplasias/diagnóstico por imagem , Óxidos
10.
Biomed Pharmacother ; 140: 111747, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34044276

RESUMO

Management of non-healing and slow to heal diabetic wounds is a major concern in healthcare across the world. Numerous techniques have been investigated to solve the issue of delayed wound healing, though, mostly unable to promote complete healing of diabetic wounds due to the lack of proper cell proliferation, poor cell-cell communication, and higher chances of wound infections. These challenges can be minimized by using hydrogel based wound healing patches loaded with bioactive agents. Gelatin methacrylate (GelMA) has been proven to be a highly cell friendly, cell adhesive, and inexpensive biopolymer for various tissue engineering and wound healing applications. In this study, S-Nitroso-N-acetylpenicillamine (SNAP), a nitric oxide (NO) donor, was incorporated in a highly porous GelMA hydrogel patch to improve cell proliferation, facilitate rapid cell migration, and enhance diabetic wound healing. We adopted a visible light crosslinking method to fabricate this highly porous biodegradable but relatively stable patch. Developed patches were characterized for morphology, NO release, cell proliferation and migration, and diabetic wound healing in a rat model. The obtained results indicate that SNAP loaded visible light crosslinked GelMA hydrogel patches can be highly effective in promoting diabetic wound healing.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Gelatina/administração & dosagem , Hidrogéis/administração & dosagem , Metacrilatos/administração & dosagem , Doadores de Óxido Nítrico/administração & dosagem , S-Nitroso-N-Acetilpenicilamina/administração & dosagem , Cicatrização/efeitos dos fármacos , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Gelatina/química , Hidrogéis/química , Luz , Metacrilatos/química , Óxido Nítrico/química , Doadores de Óxido Nítrico/química , Ratos Sprague-Dawley , S-Nitroso-N-Acetilpenicilamina/química
11.
J Adv Res ; 30: 171-184, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34026294

RESUMO

Background: Heterocyclic compounds have always been used as a core portion in the development of anticancer drugs. However, there is a pressing need for developing inexpensive and simple alternatives to high-cost and complex chemical agents-based catalysts for large-scale production of heterocyclic compounds. Also, development of some smart platforms for cancer treatment based on nanoparticles (NPs) which facilitate Fenton reaction have been widely explored by different scientists. Magnetic NPs not only can serve as catalysts in the synthesis of heterocyclic compounds with potential anticancer properties, but also are widely used as smart agents in targeting cancer cells and inducing Fenton reactions. Aim of Review: Therefore, in this review we aim to present an updated summary of the reports related to the main clinical or basic application and research progress of magnetic NPs in cancer as well as their application in the synthesis of heterocyclic compounds as potential anticancer drugs. Afterwards, specific tumor microenvironment (TME)-responsive magnetic nanocatalysts for cancer treatment through triggering Fenton-like reactions were surveyed. Finally, some ignored factors in the design of magnetic nanocatalysts- triggered Fenton-like reaction, challenges and future perspective of magnetic nanocatalysts-assisted synthesis of heterocyclic compounds and selective cancer therapy were discussed.Key Scientific Concepts of Review:This review may pave the way for well-organized translation of magnetic nanocatalysts in cancer therapy from the bench to the bedside.


Assuntos
Antineoplásicos/farmacologia , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapêutico , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/química , Catálise , Humanos , Peróxido de Hidrogênio/química , Hipertermia Induzida/métodos , Ferro/química , Fenômenos Magnéticos , Camundongos , Neoplasias/metabolismo , Fototerapia/métodos , Microambiente Tumoral/efeitos dos fármacos
12.
Transl Oncol ; 14(7): 101087, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33865030

RESUMO

Metastasis is the major reason for most brain tumors with up to a 50% chance of occurrence in patients with other types of malignancies. Brain metastasis occurs if cancer cells succeed to cross the 'blood-brain barrier' (BBB). Moreover, changes in the structure and function of BBB can lead to the onset and progression of diseases including neurological disorders and brain-metastases. Generating BBB models with structural and functional features of intact BBB is highly important to better understand the molecular mechanism of such ailments and finding novel therapeutic agents targeting them. Hence, researchers are developing novel in vitro BBB platforms that can recapitulate the structural and functional characteristics of BBB. Brain endothelial cells-based in vitro BBB models have thus been developed to investigate the mechanism of brain metastasis through BBB and facilitate the testing of brain targeted anticancer drugs. Bioengineered constructs integrated with microfluidic platforms are vital tools for recapitulating the features of BBB in vitro closely as possible. In this review, we outline the fundamentals of BBB biology, recent developments in the microfluidic BBB platforms, and provide a concise discussion of diverse types of bioengineered BBB models with an emphasis on the application of them in brain metastasis and cancer research in general. We also provide insights into the challenges and prospects of the current bioengineered microfluidic platforms in cancer research.

13.
Biomed Pharmacother ; 138: 111425, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33756154

RESUMO

Cardiovascular disease is one of the leading causes of mortality worldwide. Cardiac tissue engineering strategies focusing on biomaterial scaffolds incorporating cells and growth factors are emerging as highly promising for cardiac repair and regeneration. The use of stem cells within cardiac microengineered tissue constructs present an inherent ability to differentiate into cell types of the human heart. Stem cells derived from various tissues including bone marrow, dental pulp, adipose tissue and umbilical cord can be used for this purpose. Approaches ranging from stem cell injections, stem cell spheroids, cell encapsulation in a suitable hydrogel, use of prefabricated scaffold and bioprinting technology are at the forefront in the field of cardiac tissue engineering. The stem cell microenvironment plays a key role in the maintenance of stemness and/or differentiation into cardiac specific lineages. This review provides a detailed overview of the recent advances in microengineering of autologous stem cell-based tissue engineering platforms for the repair of damaged cardiac tissue. A particular emphasis is given to the roles played by the extracellular matrix (ECM) in regulating the physiological response of stem cells within cardiac tissue engineering platforms.


Assuntos
Microambiente Celular/fisiologia , Cardiopatias/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Miócitos Cardíacos/transplante , Engenharia Tecidual/métodos , Transplante Autólogo/métodos , Animais , Cardiopatias/fisiopatologia , Humanos , Transplante de Células-Tronco Mesenquimais/tendências , Células-Tronco Mesenquimais/fisiologia , Miócitos Cardíacos/fisiologia , Engenharia Tecidual/tendências , Transplante Autólogo/tendências
14.
J Control Release ; 333: 91-106, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33774120

RESUMO

The bioprinting technique with specialized tissue production allows the study of biological, physiological, and behavioral changes of cancerous and non-cancerous tissues in response to pharmacological compounds in personalized medicine. To this end, to evaluate the efficacy of anticancer drugs before entering the clinical setting, tissue engineered 3D scaffolds containing breast cancer and derived from the especially patient, similar to the original tissue architecture, can potentially be used. Despite recent advances in the manufacturing of 3D bioprinted breast cancer tissue (BCT), many studies still suffer from reproducibility primarily because of the uncertainty of the materials used in the scaffolds and lack of printing methods. In this review, we present an overview of the breast cancer environment to optimize personalized treatment by examining and identifying the physiological and biological factors that mimic BCT. We also surveyed the materials and techniques related to 3D bioprinting, i.e, 3D bioprinting systems, current strategies for fabrication of 3D bioprinting tissues, cell adhesion and migration in 3D bioprinted BCT, and 3D bioprinted breast cancer metastasis models. Finally, we emphasized on the prospective future applications of 3D bioprinted cancer models for rapid and accurate drug screening in breast cancer.


Assuntos
Bioimpressão , Neoplasias da Mama , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Impressão Tridimensional , Estudos Prospectivos , Reprodutibilidade dos Testes , Engenharia Tecidual , Tecidos Suporte
15.
Sci Rep ; 11(1): 5327, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33674680

RESUMO

In the present study, the effect of concentration of titanium carbide (TiC) particles on the structural, mechanical, and electrochemical properties of Ni-P composite coatings was investigated. Various amounts of TiC particles (0, 0.5, 1.0, 1.5, and 2.0 g L-1) were co-electrodeposited in the Ni-P matrix under optimized conditions and then characterized by employing various techniques. The structural analysis of prepared coatings indicates uniform, compact, and nodular structured coatings without any noticeable defects. Vickers microhardness and nanoindentation results demonstrate the increase in the hardness with an increasing amount of TiC particles attaining its terminal value (593HV100) at the concentration of 1.5 g L-1. Further increase in the concentration of TiC particles results in a decrease in hardness, which can be ascribed to their accumulation in the Ni-P matrix. The electrochemical results indicate the improvement in corrosion protection efficiency of coatings with an increasing amount of TiC particles reaching to ~ 92% at 2.0 g L-1, which can be ascribed to a reduction in the active area of the Ni-P matrix by the presence of inactive ceramic particles. The favorable structural, mechanical, and corrosion protection characteristics of Ni-P-TiC composite coatings suggest their potential applications in many industrial applications.

16.
Biomed Mater ; 16(4): 042003, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33686970

RESUMO

Advanced biomaterials are increasingly used for numerous medical applications from the delivery of cancer-targeted therapeutics to the treatment of cardiovascular diseases. The issues of foreign body reactions induced by biomaterials must be controlled for preventing treatment failure. Therefore, it is important to assess the biocompatibility and cytotoxicity of biomaterials on cell culture systems before proceeding to in vivo studies in animal models and subsequent clinical trials. Direct use of biomaterials on animals create technical challenges and ethical issues and therefore, the use of non-animal models such as stem cell cultures could be useful for determination of their safety. However, failure to recapitulate the complex in vivo microenvironment have largely restricted stem cell cultures for testing the cytotoxicity of biomaterials. Nevertheless, properties of stem cells such as their self-renewal and ability to differentiate into various cell lineages make them an ideal candidate for in vitro screening studies. Furthermore, the application of stem cells in biomaterials screening studies may overcome the challenges associated with the inability to develop a complex heterogeneous tissue using primary cells. Currently, embryonic stem cells, adult stem cells, and induced pluripotent stem cells are being used as in vitro preliminary biomaterials testing models with demonstrated advantages over mature primary cell or cell line based in vitro models. This review discusses the status and future directions of in vitro stem cell-based cultures and their derivatives such as spheroids and organoids for the screening of their safety before their application to animal models and human in translational research.

17.
Biomed Mater ; 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33592587

RESUMO

Advanced biomaterials have produced a significant impact on healthcare by improving the quality of life of people with disabilities. Biomaterials are immensely used in tissue engineering, wound healing applications, and delivery of cancer targeted therapeutics. Biocompatibility and cytotoxicity screening of biomaterials on cell culture systems is the first step before their in vivo testing in animal models and subsequent clinical trials. Direct use of biomaterials on animals may create technical challenges as well as ethical concerns. In order to avoid the ethical concerns of animal use, many non-animal models such as stem cell cultures are being developed and utilized for testing their safety. However, due to several limitations including the inability to recapitulate the complex in vivo microenvironment, the application of stem cell cultures is limited. However, properties of stem cells such as their self-renewal and ability to differentiate into various cell lineages like hepatocytes, cardiomyocytes, and neural cells make them an ideal candidates for in vitro screening studies. Furthermore, the application of stem cells may overcome the challenges associated with the inability to develop a complex heterogeneous tissue using primary cells. Currently, Embryonic Stem Cells (ESCs), Adult Stem Cells (ASCs), and Induced Pluripotent Stem Cells (iPSCs) are being used as in vitro preliminary biomaterials testing models with demonstrated advantages over mature primary cell or cell line based in vitro models. This review discusses the current status and future directions of in vitro stem cell-based cultures and their derivatives such as spheroids and organoids for the screening of their safety before their application to animal models and human in translational research.

18.
J Tissue Eng Regen Med ; 15(4): 322-335, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33432773

RESUMO

The importance of bone scaffolds has increased many folds in the last few years; however, during bone implantation, bacterial infections compromise the implantation and tissue regeneration. This work is focused on this issue while not compromising on the properties of a scaffold for bone regeneration. Biocomposite scaffolds (BS) were fabricated via the freeze-drying technique. The samples were characterized for structural changes, surface morphology, porosity, and mechanical properties through spectroscopic (Fourier transform-infrared [FT-IR]), microscopic (scanning electron microscope [SEM]), X-ray (powder X-ray diffraction and energy-dispersive X-ray), and other analytical (Brunauer-Emmett-Teller, universal testing machine Instron) techniques. Antibacterial, cellular, and hemocompatibility assays were performed using standard protocols. FT-IR confirmed the interactions of all the components. SEM illustrated porous and interconnected porous morphology. The percentage porosity was in the range of 49.75%-67.28%, and the pore size was 215.65-470.87 µm. The pore size was perfect for cellular penetration. Thus, cells showed significant proliferation onto these scaffolds. X-ray studies confirmed the presence of nanohydroxyapatite and graphene oxide (GO). The cell viability was 85%-98% (BS1-BS3), which shows no significant toxicity of the biocomposite. Furthermore, the biocomposites exhibited better antibacterial activity, no effect on the blood clotting (normal in vitro blood clotting), and less than 5% hemolysis. The ultimate compression strength for the biocomposites increased from 4.05 to 7.94 with an increase in the GO content. These exciting results revealed that this material has the potential for possible application in bone tissue engineering.

19.
Transl Oncol ; 14(4): 101015, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33493799

RESUMO

After cardiovascular disease, cancer is the leading cause of death worldwide with devastating health and economic consequences, particularly in developing countries. Inter-patient variations in anti-cancer drug responses further limit the success of therapeutic interventions. Therefore, personalized medicines approach is key for this patient group involving molecular and genetic screening and appropriate stratification of patients to treatment regimen that they will respond to. However, the knowledge related to adequate risk stratification methods identifying patients who will respond to specific anti-cancer agents is still lacking in many cancer types. Recent advancements in three-dimensional (3D) bioprinting technology, have been extensively used to generate representative bioengineered tumor in vitro models, which recapitulate the human tumor tissues and microenvironment for high-throughput drug screening. Bioprinting process involves the precise deposition of multiple layers of different cell types in combination with biomaterials capable of generating 3D bioengineered tissues based on a computer-aided design. Bioprinted cancer models containing patient-derived cancer and stromal cells together with genetic material, extracellular matrix proteins and growth factors, represent a promising approach for personalized cancer therapy screening. Both natural and synthetic biopolymers have been utilized to support the proliferation of cells and biological material within the personalized tumor models/implants. These models can provide a physiologically pertinent cell-cell and cell-matrix interactions by mimicking the 3D heterogeneity of real tumors. Here, we reviewed the potential applications of 3D bioprinted tumor constructs as personalized in vitro models in anticancer drug screening and in the establishment of precision treatment regimens.

20.
Pharm Dev Technol ; 26(4): 490-500, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33416013

RESUMO

Breast cancer is one of the leading causes of brain metastasis. Metastasis to the brain occurs if cancer cells manage to traverse the 'blood-brain barrier' (BBB), which is a barrier with a very tight junction (TJ) of endothelial cells between blood circulation and brain tissue. It is highly important to develop novel in vitro BBB models to investigate breast cancer metastasis to the brain to facilitate the screening of chemotherapeutic agents against it. We herein report the development of gelatin methacryloyl (GelMA) modified transwell insert based BBB model composed of endothelial and astrocyte cell layers for testing the efficacy of anti-metastatic agents against breast cancer metastasis to the brain. We characterized the developed model for the morphology and in vitro breast cancer cell migration. Furthermore, we investigated the effect of cisplatin, a widely used chemotherapeutic agent, on the migration of metastatic breast cancer cells using the model. Our results showed that breast cancer cells migrate across the developed BBB model. Cisplatin treatment inhibited the migration of cancer cells across the model. Findings of this study suggest that our BBB model can be used as a suitable tool to investigate breast cancer-associated brain metastasis and to identify suitable therapeutic agents against this.


Assuntos
Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/patologia , Neoplasias da Mama/patologia , Gelatina/química , Metacrilatos/química , Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/secundário , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Cisplatino/farmacologia , Feminino , Humanos , Hidrogéis , Técnicas In Vitro
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