RESUMO
Collagen crosslinking, mediated by lysyl oxidase, is an adaptive mechanism of the cardiac repair process initiated by cardiac fibroblasts postmyocardial injury. However, excessive crosslinking leads to cardiac wall stiffening, which impairs the contractile properties of the left ventricle and leads to heart failure. In this study, we investigated the role of periostin, a matricellular protein, in the regulation of lysyl oxidase in cardiac fibroblasts in response to angiotensin II and TGFß1. Our results indicated that periostin silencing abolished the angiotensin II and TGFß1-mediated upregulation of lysyl oxidase. Furthermore, the attenuation of periostin expression resulted in a notable reduction in the activity of lysyl oxidase. Downstream of periostin, ERK1/2 MAPK signaling was found to be activated, which in turn transcriptionally upregulates the serum response factor to facilitate the enhanced expression of lysyl oxidase. The periostin-lysyl oxidase association was also positively correlated in an in vivo rat model of myocardial infarction. The expression of periostin and lysyl oxidase was upregulated in the collagen-rich fibrotic scar tissue of the left ventricle. Remarkably, echocardiography data showed a reduction in the left ventricular wall movement, ejection fraction, and fractional shortening, indicative of enhanced stiffening of the cardiac wall. These findings shed light on the mechanistic role of periostin in the collagen crosslinking initiated by activated cardiac fibroblasts. Our findings signify periostin as a possible therapeutic target to reduce excessive collagen crosslinking that contributes to the structural remodeling associated with heart failure.
Assuntos
Moléculas de Adesão Celular , Fibroblastos , Proteína-Lisina 6-Oxidase , Ratos Sprague-Dawley , Animais , Proteína-Lisina 6-Oxidase/metabolismo , Fibroblastos/metabolismo , Ratos , Moléculas de Adesão Celular/metabolismo , Masculino , Sistema de Sinalização das MAP Quinases , Miocárdio/metabolismo , Miocárdio/citologia , Angiotensina II/farmacologia , Angiotensina II/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Células Cultivadas , Modelos Animais de Doenças , PeriostinaRESUMO
STUDY OBJECTIVE: To compare the economic difference in terms of overall costs between two Ambulatory Surgical Unit (ASU) settings in which a midurethral single incision sling (MSIS) can be performed. DESIGN: A retrospective cohort study was carried out, examining the implanting of an MSIS performed at two different ASU settings by a single surgeon. Total cost was determined by assessing differences in charges and subsequent reimbursement associated with the procedure at each ASU setting. Time was measured using an EMR system for tracking both patient entry/exit from the facility as well as intraoperative time. Adverse events commonly associated with the procedure and patient-reported unanticipated adverse events were collected. A validated Surgical Satisfaction Questionnaire was administered postoperatively. SETTING: University Health Network Teaching Hospital. PATIENTS: A total of 125 women with stress urinary incontinence. INTERVENTION: MSIS. MEASUREMENT AND MAIN RESULTS: Between January 2016 until August 2020, 125 women underwent an MSIS procedure. The total office-based ASU (O-ASU) charges averaged $4564.00 (reimbursement of $2642.07). The total hospital-based ASU (H-ASU) charges averaged $40 136 (reimbursement of $9000), as well as an anesthesia average charge of $800 (reimbursement of $500). The average O-ASU total patient encounter time was 53.76 minutes versus 344.702 minutes for the H-ASU. There was no difference between commonly associated or unanticipated adverse events nor global patient satisfaction. CONCLUSIONS: Based on overall cost, total encounter time, and global patient satisfaction, a certified O-ASU is an optimal site of care for MSIS for surgical management of female stress urinary incontinence.
Assuntos
Slings Suburetrais , Incontinência Urinária por Estresse , Feminino , Humanos , Incontinência Urinária por Estresse/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos , Estudos Retrospectivos , Slings Suburetrais/efeitos adversos , Satisfação do Paciente , Resultado do TratamentoRESUMO
Strong plasmon absorption in the near-infrared (NIR) region renders gold nanorods (GNRs) amenable for biomedical applications, particularly for photothermal therapy. However, these nanostructures have not been explored for their imaging potential because of their weak emission profile. In this study, the weak fluorescence emission of GNRs is tuned to match that of the absorption of a photosensitizer (PS) molecule, and energy transfer from the GNR to PS enhances the emission profile of the GNR-PS combination. GNR complexes generally quench the fluorescence emission of nearby chromophores. However, herein, the complex retains or rather enhances the fluorescence through competition in energy transfer. Excitation-dependent energy transfer has been explained experimentally and theoretically by using DFT calculations, the CIE chromaticity diagram, and power spectrum. The final GNR-PS complex modified for tumor specificity serves as an excellent organ-specific theranostic probe for bioimaging and dual therapy both in vitro and in vivo. Principal component analysis designates photodynamic therapy a better candidate than that of photothermal therapy for long-term efficacy in vivo.
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Ouro/química , Nanotubos/química , Fármacos Fotossensibilizantes/química , Nanomedicina Teranóstica/métodos , Animais , Transferência de Energia , Humanos , Luminescência , NanoestruturasRESUMO
Background & objectives: Polyethylene terephthalate (PET) graft, designed and developed at our institute for vascular reconstruction, is porous to promote optimal incorporation and neointima formation, requiring pre-clotting or biomodification by sealing the pores before implantation. The objective of this study was to characterize, test and perform preclinical evaluation of hydrogel (alginate dialdehyde cross-linked gelatin) sealed fluoropassivated PET vascular prosthesis in pig model, so as to avoid pre-clotting, for its safety and efficacy before employing the indigenous and less expensive graft for clinical use. Methods: Hydrogel sealed, fluoropassivated PET vascular prosthesis were tested for haemocompatibility and toxicity followed by small animal toxicology tests and in vivo experiments in pigs receiving implantation at thoracic aorta. All 33 animals received test as well as control grafts with a plan for phased explantation at 2, 12 and 26 weeks. All animals underwent completion angiogram at the end of procedure as well as before graft explantation. Results: Haemocompatibility tests for haemolysis and toxicity tests showed no adverse events in tested mice and rabbits. Completion angiogram showed intact anastamosis and patent graft in each animal in post-operative period and at explantation. Gross and histopathological examination showed well-encapsulated grafts, clean glistening neointima and no evidence of thrombus in both test and control grafts. Interpretation & conclusions: Hydrogel sealed, fluoropassivated PET vascular prosthesis was found non-toxic, haemocompatible and remained patent in in vivo studies at planned intervals.
Assuntos
Aorta Torácica/cirurgia , Prótese Vascular , Polietilenotereftalatos/uso terapêutico , Remodelação Vascular/efeitos dos fármacos , Alginatos/uso terapêutico , Animais , Aorta Torácica/patologia , Aorta Torácica/transplante , Prótese Vascular/efeitos adversos , Gelatina/uso terapêutico , Ácido Glucurônico/uso terapêutico , Ácidos Hexurônicos/uso terapêutico , Humanos , Hidrogéis/uso terapêutico , Camundongos , Polietilenotereftalatos/química , Coelhos , Rifampina/farmacologia , SuínosRESUMO
BACKGROUND AND AIM OF STUDY: Although the sheep is the most acceptable animal model for heart valve evaluation, it has severe limitations for detecting heart valve thrombosis during preclinical studies. While the pig offers an alternative model and is better for detecting prosthetic valve thrombogenicity, it is not often used because of inadvertent valve thrombosis or bleeding complications. The study aim was to develop an improved pig model which can be used reliably to evaluate mechanical heart valve thrombogenicity. METHODS: Mechanical heart valves were implanted in the mitral position of indigenous pigs administered aspirin-clopidogrel, and compared with similar valves implanted in control pigs to which no antiplatelet therapy had been administered. The pigs were observed for six months to study their overall survivability, inadvertent bleeding/valve thrombosis and pannus formation. The efficacy of aspirinclopidogrel on platelet aggregation and blood coagulation was also recorded and compared between test and control animals. RESULTS: In comparison to controls, pigs receiving anti-platelet therapy showed an overall better survivability, an absence of inadvertent valve thrombosis/ bleeding, and less obstructive pannus formation. Previously unreported inhibitory effects of aspirin-clopidogrel on the intrinsic pathway of blood coagulation were also observed in the pig model. Notably, with aspirin-clopidogrel therapy inadvertent thrombus formation or bleeding can be prevented. CONCLUSIONS: The newly developed pig model can be successfully used to evaluate heart valve thrombosis following chronic orthotopic valve implantation. The model may also be utilized to evaluate other bloodcontacting implantable devices.
Assuntos
Modelos Animais de Doenças , Doenças das Valvas Cardíacas/prevenção & controle , Implante de Prótese de Valva Cardíaca/efeitos adversos , Próteses Valvulares Cardíacas/efeitos adversos , Hemorragia Pós-Operatória/prevenção & controle , Trombose/prevenção & controle , Animais , Aspirina/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Plaquetas/efeitos dos fármacos , Clopidogrel , Humanos , Inibidores da Agregação Plaquetária/uso terapêutico , Suínos , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêuticoRESUMO
The wound-healing effect of insulin is well studied and reported. However, prolonged topical application of insulin without compromising its biological activity is still a challenge. In this study, the effect of topically delivered insulin on promoting wound healing in diabetic animals was evaluated. Alginate diamine PEG-g-poly(PEGMA) (ADPM2S2) was the material used for the topical delivery of insulin. ADPM2S2 hydrogels release insulin and strontium ions, and they synergistically act to regulate different phases of wound healing. Insulin was released from the ADPM2S2 hydrogel for a period of 48 h, maintaining its structural stability and biological activity. In vitro studies were performed under high-glucose conditions to evaluate the wound-healing potential of insulin. Insulin-loaded ADPM2S2 hydrogels showed significant improvement in cell migration, proliferation, and collagen deposition, compared to control cells under high-glucose conditions. Immunostaining studies in L929 cells showed a reduction in phospho Akt expression under high-glucose conditions, and in the presence of insulin, the expression increased. The gene expression studies revealed that insulin plays an important role in regulating the inflammatory phase and macrophage polarization, which favors accelerated wound closure. In vivo experiments in diabetic rat excision wounds treated with insulin-loaded ADPM2S2 showed 95% wound closure within 14 days compared with 82% in control groups. Thus, both the in vitro and in vivo results signify the therapeutic potential of topically delivered insulin in wound management under high-glucose conditions.
Assuntos
Diabetes Mellitus Experimental , Insulina , Ratos , Animais , Insulina/farmacologia , Insulina/uso terapêutico , Diabetes Mellitus Experimental/tratamento farmacológico , Hidrogéis/química , Alginatos/farmacologia , Alginatos/química , Alginatos/uso terapêutico , Cicatrização/fisiologia , Glucose/farmacologia , Glucose/uso terapêuticoRESUMO
Correction for 'Optically controlled hybrid metamaterial of plasmonic spiky gold inbuilt graphene sheets for bimodal imaging guided multimodal therapy' by Ramapurath S. Jayasree et al., Biomater. Sci., 2020, 8, 3381-3391, https://doi.org/10.1039/D0BM00312C.
RESUMO
Hybrid nanoparticles are innovative invention of last decade designed to overcome limitations of single-component nanoparticles by introducing multiple functionalities through combining two or more different nanoparticles. In this study, we are reporting development of magneto-fluorescent hybrid nanoparticles by combining iron oxide and carbon nanoparticles to enablein vivofluorescence imaging which also has all the required characteristic properties to use as Magnetic Resonance Imaging (MRI) contrast agent. In order to achieve dual-functional imaging, alginate and pullulan coated super paramagnetic iron oxide nanoparticles (ASPION and PSPION) and Carbon dots (Cdts) were synthesised separately. ASPIONs and PSPIONs were further chemically conjugated with Cdts and developed dual-functional nanohybrid particles ASPION-Cdts and PSPION-Cdts. Subsequently, evaluation of the materials for its size, functionalisation efficiency, fluorescence and magnetic properties, biocompatibility and cellular uptake efficiency has been carried out. Fluorescence imaging of liver fibrosis was performedin vivoin rodent model of liver fibrosis using the two nanohybrids, which is further confirmed by high fluorescence signal from the harvested liver.
Assuntos
Carbono , Nanopartículas , Humanos , Carbono/química , Compostos Férricos/química , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/diagnóstico por imagem , Nanopartículas/química , Meios de Contraste/químicaRESUMO
Alzheimer's disease (AD) is a progressive complex neurodegenerative disorder affecting millions of individuals worldwide. Currently, there is no effective treatment for AD. AD is characterized by the deposition of amyloid plaques/fibrils. One major strategy for managing this disease is by slowing the progression of AD using different drugs which could potentially limit free-radical formation, oxidative stress and lipid peroxidation and promote the survival of neurons exposed to ß-amyloid. Inhibition of amyloid fibrillization and clearance of amyloid plaques/fibrils are essential for the prevention and treatment of AD. The thiophilic interaction between the side chain of an aromatic residue in a polypeptide and a sulphur atom of the compound can effectively inhibit amyloid fibril formation. In this work, we have synthesized cysteine-capped gold nanoclusters (Cy-AuNCs) which exhibit inherent red emission and can disintegrate amyloid fibrils through the aforementioned thiophilic interactions. Herein, we also used molecular docking to study the thiophilic interactions between the sulphur atom of Cy-AuNCs and the aromatic rings of the protein. Finally, the gold cluster was functionalized with a brain targeting molecule, Levodopa (AuCs-LD), to specifically target the brain and to facilitate passage through the blood brain barrier (BBB). Both Cy-AuNCs and AuCs-LD showed good biocompatibility and the inherent fluorescence properties of nanoclusters enabled real time imaging. The efficacy of the nanoclusters to disintegrate amyloid fibrils and their ability to cross the BBB were demonstrated both in vitro and in vivo in the BBB model and the AD animal model respectively. Our results imply that nanoparticle-based artificial molecular chaperones may offer a promising therapeutic approach for AD.
Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Animais , Peptídeos beta-Amiloides/metabolismo , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Cisteína , Amiloide/química , Placa Amiloide , Ouro/química , Simulação de Acoplamento Molecular , Enxofre/uso terapêuticoRESUMO
Fibrosis that occurs after nonfatal myocardial infarction (MI) is an irreversible reparative cardiac tissue remodeling process characterized by progressive deposition of highly cross-linked type I collagen. No currently available therapeutic strategy prevents or reverses MI-associated fibrotic scarring of myocardium. In this study, we used an epicardial graft prepared of porcine cholecystic extracellular matrix to treat experimental nonfatal MI in rats. Graft-assisted healing was characterized by reduced fibrosis, with scanty deposition of type I collagen. Histologically, the tissue response was associated with a favorable regenerative reaction predominated by CD4-positive helper T lymphocytes, enhanced angiogenesis, and infiltration of proliferating cells. These observations indicate that porcine cholecystic extracellular matrix delayed the fibrotic reaction and support its use as a potential biomaterial for mitigating fibrosis after MI. Delaying the progression of cardiac tissue remodeling may widen the therapeutic window for management of scarring after MI.
Assuntos
Infarto do Miocárdio , Doenças dos Suínos , Ratos , Suínos , Animais , Colágeno Tipo I , Cicatriz/patologia , Remodelação Ventricular , Infarto do Miocárdio/complicações , Infarto do Miocárdio/patologia , Miocárdio/patologia , Matriz Extracelular/patologia , FibroseRESUMO
Prolonged usage of traditional nanomaterials in the biological field has posed several short- and long-term toxicity issues. Over the past few years, smart nanomaterials (SNs) with controlled physical, chemical, and biological features have been synthesized in an effort to allay these challenges. The current study seeks to develop theranostic SNs based on iron oxide to enable simultaneous magnetic hyperthermia and magnetic resonance imaging (MRI), for chronic liver damage like liver fibrosis which is a major risk factor for hepatocellular carcinoma. To accomplish this, superparamagnetic iron oxide nanoparticles (SPIONs) were prepared, coated with a biocompatible and naturally occurring polysaccharide, alginate. The resultant material, ASPIONs were evaluated in terms of physicochemical, magnetic and biological properties. A hydrodynamic diameter of 40 nm and a transverse proton relaxation rate of 117.84 mM-1 s-1 pronounces the use of ASPIONs as an efficient MRI contrast agent. In the presence of alternating current of 300 A, ASPIONs could elevate the temperature to 45 °C or more, with the possibility of hyperthermia based therapeutic approach. Magnetic therapeutic and imaging potential of ASPIONs were further evaluated respectively in vitro and in vivo in HepG2 carcinoma cells and animal models of liver fibrosis, respectively. Finally, to introduce dual imaging capability along with magnetic properties, ASPIONs were conjugated with near infrared (NIR) dye Atto 700 and evaluated its optical imaging efficiency in animal model of liver fibrosis. Histological analysis further confirmed the liver targeting efficacy of the developed SNs for Magnetic theranostics and optical imaging as well as proved its short-term safety, in vivo.
Assuntos
Carcinoma Hepatocelular , Hipertermia Induzida , Neoplasias Hepáticas , Nanopartículas de Magnetita , Animais , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Linhagem Celular Tumoral , Hipertermia Induzida/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Imageamento por Ressonância Magnética/métodos , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/terapia , Hipertermia , Nanopartículas de Magnetita/químicaRESUMO
Cardiac tissue engineering using cells, scaffolds or signaling molecules is a promising approach for replacement or repair of damaged myocardium. This study addressed the contemporary need for a conductive biomimetic nanocomposite scaffold for cardiac tissue engineering by examining the use of a gold nanoparticle-incorporated porcine cholecystic extracellular matrix for the same. The scaffold had an electrical conductivity (0.74 ± 0.03 S/m) within the range of native myocardium. It was a suitable substrate for the growth and differentiation of cardiomyoblast (H9c2) as well as rat mesenchymal stem cells to cardiomyocyte-like cells. Moreover, as an epicardial patch, the scaffold promoted neovascularisation and cell proliferation in infarcted myocardium of rats. It was concluded that the gold nanoparticle coated cholecystic extracellular matrix is a prospective biomaterial for cardiac tissue engineering.
Assuntos
Nanopartículas Metálicas , Alicerces Teciduais , Animais , Condutividade Elétrica , Matriz Extracelular , Ouro/química , Miocárdio , Miócitos Cardíacos , Estudos Prospectivos , Ratos , Suínos , Engenharia Tecidual , Alicerces Teciduais/químicaRESUMO
Compromised angiogenesis is a major factor contributing delayed wound healing in diabetic patients. Graft-assisted healing using synthetic and natural scaffolds supplemented with micromolecules for stimulating angiogenesis is the contemporary tissue engineering strategy for treating diabetic wounds. This study deployed the carbodiimide chemical reaction for coupling gelatin with a porcine cholecyst-derived scaffold (CDS) for enhancing angiogenesis. The modification was confirmed by the trinitrobenzene sulfonic acid assay and scanning electron microscopy. The gelatin-coupled CDS was more stable than the bare CDS in an in vitro proteolytic environment and allowed survival of keratinocytes (HaCaT), indicating its suitability for chronic skin wound application. The gelatin coupling brought significant improvement in the in vitro angiogenic potential of the CDS as evident from the enhanced viability of endothelial cells. An in ovo chorioallantoic membrane assay also demonstrated the angiogenic potential of the modified scaffold. Further, the modified scaffold promoted angiogenesis and aided faster healing of full-thickness excision wounds in streptozotocin-induced diabetic rats. It is concluded that the gelatin-coupled CDS is a potential advanced wound care material for treating diabetic wounds.
Assuntos
Materiais Biocompatíveis/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Vesícula Biliar/química , Gelatina/farmacologia , Neovascularização Patológica/tratamento farmacológico , Cicatrização/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Diabetes Mellitus Experimental/induzido quimicamente , Gelatina/química , Teste de Materiais , Neovascularização Patológica/induzido quimicamente , Tamanho da Partícula , Ratos , Ratos Wistar , Estreptozocina , Suínos , Engenharia Tecidual , Alicerces Teciduais/químicaRESUMO
Polypropylene (PP) meshes are widely used for repairing skeletal muscle defects like abdominal hernia despite the chances of undesirable pro-inflammatory tissue reactions that demand revision surgeries in about 45% of cases. Attempts have been made to address the problem by modifying the mesh surface and architecture. These procedures have yielded only incremental improvements in the management of overall postoperative complications, and the search for a clinically viable therapeutic strategy continues. This study deployed a tissue engineering approach for mitigating PP-induced adverse tissue reaction by dip-coating the mesh with a hydrogel formulation of the porcine cholecystic extracellular matrix (CECM). The biomaterial properties of the CECM hydrogel-coated PP (C-PP) meshes were studied and their biocompatibility was evaluated by in vitro and in vivo tests based on ISO standards. Further, the nature of tissue reactions induced by the hydrogel-coated mesh and a commercial PP hernia repair graft was compared in a rat model of partial-thickness abdominal wall defect. Histomorphologically, in comparison with the PP graft-induced tissue reaction, C-PP caused a favorable graft-acceptance response characterized by reduced numbers of pro-inflammatory M1 macrophages and cytotoxic lymphocytes. Remarkably, the differential inflammatory response of the C-PP graft-assisted healing was associated with a fibrotic reaction predominated by deposition of type I collagen rather than type III collagen, as desired during skeletal muscle repair. It was concluded that the CECM hydrogel is a potential biomaterial for surface modification of polymeric biomedical devices.
Assuntos
Materiais Revestidos Biocompatíveis/química , Matriz Extracelular/química , Vesícula Biliar/química , Hidrogéis/química , Polipropilenos/química , Telas Cirúrgicas , Animais , Linhagem Celular , Teste de Materiais , Camundongos , Tamanho da Partícula , Propriedades de Superfície , Suínos , Engenharia TecidualRESUMO
Early diagnosis and therapy of liver fibrosis is of utmost importance, especially considering the increased incidence of alcoholic and non-alcoholic liver syndromes. In this work, a systematic study is reported to develop a dual function and biocompatible nanoprobe for liver specific diagnostic and therapeutic applications. A polysaccharide polymer, pullulan stabilized iron oxide nanoparticle (P-SPIONs) enabled high liver specificity via asialogycoprotein receptor mediation. Longitudinal and transverse magnetic relaxation rates of 2.15 and 146.91 mM-1 s-1 respectively and a size of 12 nm, confirmed the T2 weighted magnetic resonance imaging (MRI) efficacy of P-SPIONs. A current of 400A on 5 mg/ml of P-SPIONs raised the temperature above 50 °C, to facilitate effective hyperthermia. Finally, a NIR dye conjugation facilitated targeted dual imaging in liver fibrosis models, in vivo, with favourable histopathological results and recommends its use in early stage diagnosis using MRI and optical imaging, and subsequent therapy using hyperthermia.
Assuntos
Receptor de Asialoglicoproteína/metabolismo , Biomarcadores , Glucanos , Cirrose Hepática/diagnóstico , Cirrose Hepática/metabolismo , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita , Imagem Óptica/métodos , Animais , Materiais Biocompatíveis , Linhagem Celular Tumoral , Sobrevivência Celular , Fenômenos Químicos , Técnicas de Química Sintética , Compostos Férricos/química , Glucanos/química , Cirrose Hepática/etiologia , Cirrose Hepática/terapia , Nanopartículas de Magnetita/química , Masculino , Sondas Moleculares/síntese química , Sondas Moleculares/química , Terapia de Alvo Molecular/métodos , Ratos , Espécies Reativas de OxigênioRESUMO
In the current study, three-dimensional (3D) nanofibrous scaffolds with pore sizes in the range of 24-250 µm and 24-190 µm were fabricated via a two-step electrospinning method to overcome the limitation of obtaining three-dimensionality with large pore sizes for islet culture using conventional electrospinning. The scaffolds supported the growth and differentiation of adipose-derived mesenchymal stem cells to islet-like clusters (ILCs). The pore size of the scaffolds was found to influence the cluster size, viability and insulin release of the differentiated islets. Hence, islet clusters of the desired size could be developed for transplantation to overcome the loss of bigger islets due to hypoxia which adversely impacts the outcome of transplantation. The tissue-engineered constructs with ILC diameter of 50 µm reduced glycemic value within 3-4 weeks after implantation in the omental pouch of diabetic rats. Detection of insulin in the serum of implanted rats demonstrates that the tissue-engineered construct is efficient to control hyperglycemia. Our findings prove that the 3D architecture and pore size of scaffolds regulates the morphology and size of islets during differentiation which is critical in the survival and function of ILCs in vitro and in vivo.
Assuntos
Diabetes Mellitus Experimental/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Animais , Diferenciação Celular , Células Cultivadas , Masculino , Porosidade , Ratos , Ratos WistarRESUMO
Limbal stem cell deficiency (LSCD) is the loss of limbal stem cells that reside in the corneoscleral junction resulting in vision loss or blindness. Bilateral LSCD is usually treated by allogeneic corneal transplantation, with instances of tissue rejection or failure in long-term follow-up. This study aims to use adipose mesenchymal stem cells (ASC) as an alternative autologous cell source for treating bilateral limbal deficiency conditions. ASCs derived from rabbit fat tissue were differentiated into corneal epithelial lineage using limbal explant condition media. Apart from transdifferentiation, ASC sheets were developed to facilitate effective delivery of these cells to the damage site. A thermoresponsive polymer N-isopropylacrylamide-co-glycidylmethacrylate (NGMA) was synthesized and characterized to demonstrate ASC sheet formation. Transdifferentiated ASCs showed positive expression of corneal epithelial marker CK3/12 on immunostaining, supported by gene expression studies. in vivo studies by transplanting cell sheet in rabbit models of corneal injury showed clear and smooth cornea in comparison to the sham models. Histology revealed a sheet of cells aligned and integrated on to the injured corneal surface, 1 month posttransplantation. Identifying ASCs as an alternative cell source along with cell sheet technology will be a novel step in the field of corneal surface therapies.
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Extremidades/patologia , Células-Tronco/citologia , Engenharia Tecidual/métodos , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Animais , Diferenciação Celular , Linhagem da Célula , Córnea/patologia , Doenças da Córnea/patologia , Meios de Cultivo Condicionados , Células Epiteliais/citologia , Perfilação da Expressão Gênica , Limbo da Córnea/citologia , Masculino , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Polímeros/química , Coelhos , Transplante de Células-TroncoRESUMO
The development of multifunctional molecular diagnostic platforms for the concordant visualization and treatment of diseases with high sensitivity and resolution has recently become a crucial strategy in cancer management. Thus, engineering functional metamaterials with high therapeutic and imaging capabilities to elucidate diseases from their morphological behaviors to physiological mechanisms is an unmet need in the current scenario. Here, we report the design of a unique hybrid plasmonic nanoarchitecture for targeted multiple phototherapies of breast cancer by simultaneous real-time monitoring through fluorescence and surface-enhanced Raman scattering (SERS) techniques. The nanoframework consisted of plasmonic gold-graphene hybrids tethered with folic acid-ligated chitosan-modified photosensitizer (PpIX) to afford target-specific localized photothermal and photodynamic therapy. The hybrid vehicle also served as an excellent nanocarrier for the efficient loading and stimuli-responsive release of the chemotherapeutic drug doxorubicin (DOX) to enhance the therapeutic efficacy, thereby forming a trimodal nanomedicine against cancer. The cytotoxic effects induced by the cumulative action of the triplet therapeutic tools were visualized through both fluorescence and SERS imaging channels. Moreover, it also generated synchronized therapeutic effects resulting in the effective regression of tumor volume without propagating any toxic effects to other organs of the animals. Taken together, by virtue of strong light-matter interactions, the nanoprobe showed enhanced photoadsorption, which facilitated amplified light-reactive therapeutic and imaging efficacies along with targeted and enhanced chemotherapy, both in vitro and in vivo, which may offer promising outcomes in clinical research.
Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Ouro/administração & dosagem , Grafite/administração & dosagem , Nanoestruturas/administração & dosagem , Neoplasias/terapia , Fármacos Fotossensibilizantes/administração & dosagem , Protoporfirinas/administração & dosagem , Animais , Antibióticos Antineoplásicos/química , Linhagem Celular Tumoral , Quitosana/administração & dosagem , Quitosana/química , Doxorrubicina/química , Ácido Fólico/administração & dosagem , Ácido Fólico/química , Ouro/química , Grafite/química , Humanos , Camundongos , Nanoestruturas/química , Neoplasias/patologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/efeitos da radiação , Fototerapia , Protoporfirinas/química , Protoporfirinas/efeitos da radiação , Análise Espectral RamanRESUMO
INTRODUCTION: Obesity is a chronic disease due to excess fat storage, a genetic predisposition, and environmental contribution where surgery offers a viable treatment option. The surgical treatment of obesity in the elderly population (> 55 years) remains controversial. PURPOSE: To evaluate the safety and efficacy of laparoscopic sleeve gastrectomy (LSG) and laparoscopic Roux-en-Y gastric bypass (LRYGB) in elderly bariatric patients. MATERIALS AND METHODS: Data was sourced from MEDLINE, EMBASE, CINAHL, PubMed, and Cochrane databases for peer-reviewed, randomized controlled trials, and observational studies in the English language were searched from the year 1991 until 2019. From the extracted data, early and late procedural complications and mortality were used as safety outcomes. Weight loss was the primary outcome for effectiveness while the resolution of obesity-related comorbidities was included as secondary outcomes. The Review Manager (Rev Man 5.3)™ software was used for statistical analysis. RESULTS: Of the forty-one screened studies, nine studies were included in the final analysis. There was no difference between LSG and LRYGB regarding early complications and mortality 3.6% versus 5.8% (p = 0.15) and 0.1% versus 0.8% (p = 0.27). Patients who underwent LRYGB had more late complications compared with those who underwent LSG (0.07% and 0.03%, p = 0.001). There was no difference in terms of weight loss at the end of 1 year. Patients who underwent LRYGB had a better resolution of obesity-related comorbidities, not statistically significant. CONCLUSION: LRYGB has better efficacy when compared with LSG. However, high-risk elderly patients should be considered for LSG given the lesser morbidity and comparable efficacy with LRYGB.
Assuntos
Derivação Gástrica , Laparoscopia , Obesidade Mórbida , Idoso , Gastrectomia , Humanos , Obesidade Mórbida/cirurgia , Resultado do Tratamento , Redução de PesoRESUMO
Herein we have reported a new magneto-fluorescent nanogel built on photoluminescent comacromer [PEG-maleic acid-glycine], N,N-dimethyl aminoethylmethacrylate and citrate-capped superparamagnetic iron oxide nanoparticles (SPION). The nanogel was found to have core-shell morphology (SPION core and PEG shell) with particle size around 80 nm. The cytocompatibility of the synthesized nanogel was studied using MTT, live/dead assays, and flow cytometry. The cellular uptake of the nanogel on cervical cancer cell line Hela evaluated through Prussian blue staining and fluorescence microscopy has revealed good cancer cell imaging capability. Magnetic hyperthermia experiments have shown that the synthesized nanogel caused the lysis of cancer cells. The fluorescence bioimaging capability of the nanogel in the murine model has shown good near IR imaging capability. Overall, the reported results suggest that the magneto-fluorescent nanogel shows promising future potential for cancer theranostic applications.