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1.
Int J Mol Sci ; 24(7)2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37047307

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) is the primary reason for cancer-related deaths in the US. Genetic mutations, drug resistance, the involvement of multiple signaling pathways, cancer stem cells (CSCs), and desmoplastic stroma, which hinders drug penetrance, contribute to poor chemotherapeutic efficacy. Hence, there is a need to identify novel drugs with improved delivery to improve treatment outcomes. Curcumin is one such compound that can inhibit multiple signaling pathways and CSCs. However, curcumin's clinical applicability for treating PDAC is limited because of its poor solubility in water and metabolic instability. Hence, we developed a difluorinated curcumin (CDF) analog that accumulates selectively in the pancreas and inhibits PDAC growth in vitro and in vivo. In the present work, we developed its 2-hydroxy-propyl-ß-cyclodextrin (HCD) inclusion complex to increase its water solubility and hydrolytic stability. The CDFHCD inclusion complex was characterized by spectroscopic, thermal, and microscopic techniques. The inclusion complex exhibited increased aqueous solubility, hydrolytic stability, and antiproliferative activity compared to parent CDF. Moreover, CDF and CDFHCD inhibited colony and spheroid formation, and induced cell cycle and apoptosis in PDAC cell lines. Hence, CDFHCD self-assembly is an efficient approach to increase water solubility and anticancer therapeutic efficacy, which now warrants advancement towards a clinical proof of concept in PDAC patients.


Assuntos
Carcinoma Ductal Pancreático , Curcumina , Neoplasias Pancreáticas , Humanos , Curcumina/química , 2-Hidroxipropil-beta-Ciclodextrina/farmacologia , 2-Hidroxipropil-beta-Ciclodextrina/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/tratamento farmacológico , Solubilidade , Água , Neoplasias Pancreáticas
2.
Front Immunol ; 14: 1342429, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38250062

RESUMO

Sarcoidosis is a chronic granulomatous disorder characterized by unknown etiology, undetermined mechanisms, and non-specific therapies except TNF blockade. To improve our understanding of the pathogenicity and to predict the outcomes of the disease, the identification of new biomarkers and molecular endotypes is sorely needed. In this study, we systematically evaluate the biomarkers identified through Omics and non-Omics approaches in sarcoidosis. Most of the currently documented biomarkers for sarcoidosis are mainly identified through conventional "one-for-all" non-Omics targeted studies. Although the application of machine learning algorithms to identify biomarkers and endotypes from unbiased comprehensive Omics studies is still in its infancy, a series of biomarkers, overwhelmingly for diagnosis to differentiate sarcoidosis from healthy controls have been reported. In view of the fact that current biomarker profiles in sarcoidosis are scarce, fragmented and mostly not validated, there is an urgent need to identify novel sarcoidosis biomarkers and molecular endotypes using more advanced Omics approaches to facilitate disease diagnosis and prognosis, resolve disease heterogeneity, and facilitate personalized medicine.


Assuntos
Doença Granulomatosa Crônica , Sarcoidose , Humanos , Biomarcadores , Algoritmos , Aprendizado de Máquina , Sarcoidose/diagnóstico , Sarcoidose/genética
3.
Nanomedicine (Lond) ; 16(22): 1963-1982, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34431318

RESUMO

Aim: To differentiate mesenchymal stem cells into functional dopaminergic neurons using an electrospun polycaprolactone (PCL) and graphene (G) nanocomposite. Methods: A one-step approach was used to electrospin the PCL nanocomposite, with varying G concentrations, followed by evaluating their biocompatibility and neuronal differentiation. Results: PCL with exiguous graphene demonstrated an ideal nanotopography with an unprecedented combination of guidance stimuli and substrate cues, aiding the enhanced differentiation of mesenchymal stem cells into dopaminergic neurons. These newly differentiated neurons were seen to exhibit unique neuronal arborization, enhanced intracellular Ca2+ influx and dopamine secretion. Conclusion: Having cost-effective fabrication and room-temperature storage, the PCL-G nanocomposites could pave the way for enhanced neuronal differentiation, thereby opening a new horizon for an array of applications in neural regenerative medicine.


Assuntos
Grafite , Células-Tronco Mesenquimais , Nanocompostos , Nanofibras , Diferenciação Celular , Humanos , Poliésteres , Engenharia Tecidual , Alicerces Teciduais
4.
Stem Cells Transl Med ; 10(2): 303-319, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33049125

RESUMO

Among conventional fabrication techniques, freeze-drying process has widely been investigated for polymeric implants. However, the understanding of the stem cell progenitor-dependent cell functionality modulation and quantitative analysis of early osseointegration of highly porous scaffolds have not been explored. Here, we developed a novel, highly porous, multimaterial composite, chitosan/hydroxyapatite/polycaprolactone (CHT/HA/PCL). The in vitro studies have been performed using mesenchymal stem cells (MSCs) from three tissue sources: human bone marrow-derived MSCs (BM-MSCs), adipose-derived MSCs (AD-MSCs), and Wharton's jelly-derived MSCs (WJ-MSCs). Although cell attachment and metabolic activity [3-4,5-dimethylthiazol-2yl-(2,5 diphenyl-2H-tetrazoliumbromide) assay] were ore enhanced in WJ-MSC-laden CHT/HA/PCL composites, scanning electron microscopy, real-time gene expression (alkaline phosphatase [ALP], collagen type I [Col I], osteocalcin [OCN], and bone morphogenetic protein 4 [BMP-4]), and immunostaining (COL I, ß-CATENIN, OCN, and SCLEROSTIN [SOST]) demonstrated pronounced osteogenesis with terminal differentiation on BM-MSC-laden CHT/HA/PCL composites only. The enhanced cell functionality on CHT/HA/PCL composites was explained in terms of interplay among the surface properties and the optimal source of MSCs. In addition, osteogenesis in rat tibial model over 6 weeks confirmed a better ratio of bone volume to the total volume for BM-MSC-laden composites over scaffold-only and defect-only groups. The clinically conformant combination of 3D porous architecture with pore sizes varying in the range of 20 to 200 µm together with controlled in vitro degradation and early osseointegration establish the potential of CHT/HA/PCL composite as a potential cancellous bone analog.


Assuntos
Quitosana , Células-Tronco Mesenquimais , Osteogênese , Alicerces Teciduais , Animais , Diferenciação Celular , Durapatita , Porosidade , Ratos
5.
Mater Sci Eng C Mater Biol Appl ; 106: 110247, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753401

RESUMO

Biodegradable porous iron having topologically ordered porosity and tailorable properties as per the required application has been the major requirement in the field of biodegradable biomaterials. Hence, in the present study, iron scaffolds with the topologically ordered porous structure were developed and for the first time, the effect of the variation in the topology on the in vitro degradation behaviour, cytocompatibility and hemocompatibility were investigated. Iron scaffold samples were fabricated using a novel process based on the combination of 3D printing and pressureless microwave sintering. To investigate the effect of topology, two different types of topological structures namely Truncated Octahedron (TO) (with variable strut size) and Cubic (C) were used. From the morphological characterization, it was found that fabricated iron scaffold possessed interconnected porosity varying from 50.70%-80.97% which included the random microporosities in the strut and designed macroporosity. Furthermore, it was inferred that the topology of the iron scaffold significantly affected its degradation properties and cytocompatibility. Increase in the weight loss, corrosion rate and reduction in cell viability with the reduction in porosity were obtained. The maximum corrosion rate and weight loss achieved was 1.64 mmpy and 6.4% respectively. Direct cytotoxicity test results revealed cytotoxicity, while prepared iron scaffold samples exhibited excellent hemocompatibility and anti-platelet adhesion property. A comparative study with relevant literature was performed and it was established that the developed iron scaffold exhibited favorable degradation and biological properties which could be tailored to suit appropriate bone tissue engineering applications.


Assuntos
Materiais Biocompatíveis/química , Impressão Tridimensional , Alicerces Teciduais/química , Células 3T3 , Animais , Eletroquímica , Teste de Materiais , Camundongos , Micro-Ondas , Porosidade , Engenharia Tecidual/métodos
6.
Mol Cell Biochem ; 448(1-2): 17-26, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29450799

RESUMO

Mesenchymal stem cells (MSCs) have shown promising outcomes in cardiac and neuronal diseases. Efficient and noninvasive tracking of MSCs is essential to harness their therapeutic potential. Iron oxide nanoparticles (IONPs) have emerged as effective means to label stem cells and visualize them using magnetic resonance imaging (MRI). It is known that IONPs do not affect viability and cell proliferation of stem cells. However, very few studies have demonstrated differentiation potential of iron oxide-labeled MSCs and their differentiation into specific lineages that can contribute to cellular therapies. The differentiation of IONP-labeled human bone marrow mesenchymal stem cells (hBM-MSCs) into cardiac and neuronal lineages has never been studied. In this study, we have shown that IONP-labeled hBM-MSCs retain their differentiation potential to cardiac and neuronal cell lineages. We also confirmed that labeling hBM-MSCs with IONP does not affect their characteristic properties such as viability, cellular proliferation rate, surface marker profiling, and trilineage differentiation capacity. This study shows that IONP can be efficiently tracked, and its labeling does not alter stemness and differentiation potential of hBM-MSCs. Thus, the labeled hBM-MSCs can be used in clinical therapies and regenerative medicine.


Assuntos
Células da Medula Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Compostos Férricos/farmacologia , Células-Tronco Mesenquimais/metabolismo , Miócitos Cardíacos/metabolismo , Neurônios/metabolismo , Coloração e Rotulagem , Células da Medula Óssea/citologia , Feminino , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Miócitos Cardíacos/citologia , Nanopartículas , Neurônios/citologia
7.
Indian J Med Res ; 142(6): 747-58, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26831424

RESUMO

BACKGROUND & OBJECTIVES: There is a significant bone tissue loss in patients from diseases and traumatic injury. The current autograft transplantation gold standard treatment has drawbacks, namely donor site morbidity and limited supply. The field of tissue engineering has emerged with a goal to provide alternative sources for transplantations to bridge this gap between the need and lack of bone graft. The aim of this study was to prepare biocomposite scaffolds based on chitosan (CHT), polycaprolactone (PCL) and hydroxyapatite (HAP) by freeze drying method and to assess the role of scaffolds in spatial organization, proliferation, and osteogenic differentiation of human mesenchymal stem cells (hMSCs) in vitro, in order to achieve bone graft substitutes with improved physical-chemical and biological properties. METHODS: Pure chitosan (100CHT) and composites (40CHT/HAP, 30CHT/HAP/PCL and 25CHT/HAP/PCL scaffolds containing 40, 30, 25 parts per hundred resin (phr) filler, respectively) in acetic acid were freeze dried and the porous foams were studied for physicochemical and in vitro biological properties. RESULTS: Scanning electron microscope (SEM) images of the scaffolds showed porous microstructure (20-300 µm) with uniform pore distribution in all compositions. Materials were tested under compressive load in wet condition (using phosphate buffered saline at pH 7.4). The in vitro studies showed that all the scaffold compositions supported mesenchymal stem cell attachment, proliferation and differentiation as visible from SEM images, [3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) assay, alkaline phosphatase (ALP) assay and quantitative reverse transcription (qRT)-PCR. INTERPRETATION & CONCLUSIONS: Scaffold composition 25CHT/HAP/PCL showed better biomechanical and osteoinductive properties as evident by mechanical test and alkaline phosphatase activity and osteoblast specific gene expression studies. This study suggests that this novel degradable 3D composite may have great potential to be used as scaffold in bone tissue engineering.


Assuntos
Diferenciação Celular , Células-Tronco Mesenquimais/citologia , Osteoblastos/citologia , Alicerces Teciduais , Fosfatase Alcalina/metabolismo , Células Cultivadas , Quitosana , Durapatita , Humanos , Técnicas In Vitro , Células-Tronco Mesenquimais/enzimologia , Microscopia Eletrônica de Varredura , Poliésteres
8.
J Comput Assist Tomogr ; 38(3): 415-23, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24681855

RESUMO

OBJECTIVE: The aim of this study was to evaluate the role of whole-body magnetic resonance imaging (WB-MRI) in imaging of extrapulmonary tuberculosis. METHODS: Eighteen patients with single-site extrapulmonary tuberculosis were evaluated with contrast-enhanced dedicated MRI of the clinically symptomatic site followed by WB-MRI using contrast-enhanced 3-dimensional (3D) modified DIXON technique (m-DIXON) and diffusion-weighted WB imaging with background body signal suppression (DWIBS) sequences. Studies were read by 2 experienced radiologists, and additional lesions seen on WB-MRI were separately charted. RESULTS: Of 18 patients, 14 were found to have asymptomatic involvement of other organs on WB-MRI. In 5 patients, the information was helpful in choosing an easily accessible site for biopsy/aspiration. Postcontrast 3D m-DIXON was better in picking up brain and lymph nodal lesions, whereas DWIBS was better in detecting vertebral lesions. CONCLUSIONS: Whole-body MRI may be used for assessing the asymptomatic involvement of other body organs in tuberculosis. The combination of postcontrast 3D m-DIXON and DWIBS is complementary and may provide a road map for biopsy of accessible lesions.


Assuntos
Imunocompetência/imunologia , Imageamento por Ressonância Magnética/métodos , Tuberculose/imunologia , Tuberculose/patologia , Imagem Corporal Total/métodos , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
9.
Int J Cardiol ; 163(1): 93-9, 2013 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-21903280

RESUMO

BACKGROUND: The majority of the protocols for cardiomyocyte differentiation of MSC use 5-azacytidine as an inducer. As transforming growth factor ß1 and 5-azacytidine share similar target signaling pathways, we examined whether transforming growth factor ß1 can play a role in cardiac differentiation process in human mesenchymal stem cell of bone marrow origin. METHODS: The differentiation protocol involving transforming growth factor ß1 was compared with that of 5-azacytidine in these cells. The two differentiation regimes were compared using reverse transcriptase PCR, flow cytometry, and quantitative PCR. RESULTS: We observed that in both cases, acquired morphological features were similar. Protein and gene expression assays also indicated similar cardiac marker expression profile in both the differentiation conditions. Furthermore, transforming growth factor ß1 and 5-azacytidine allowed the acquisition of comparable levels of cardiac cell like molecular characteristic as attested by evaluation of myosin light chain-2v expression. CONCLUSION: In conclusion, we demonstrate that transforming growth factor ß1 can play a similar role in cardiac differentiation process of human bone marrow mesenchymal stem cells.


Assuntos
Células da Medula Óssea/citologia , Diferenciação Celular/fisiologia , Células-Tronco Mesenquimais/citologia , Miócitos Cardíacos/citologia , Fator de Crescimento Transformador beta1/fisiologia , Adolescente , Adulto , Azacitidina/farmacologia , Células da Medula Óssea/fisiologia , Linhagem da Célula/fisiologia , Células Cultivadas , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Células-Tronco Mesenquimais/fisiologia , Miócitos Cardíacos/fisiologia , Adulto Jovem
10.
Neuroimaging Clin N Am ; 22(4): 557-83, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23122257

RESUMO

Central nervous system infections account for 1% of primary hospital admissions and 2% of nosocomial infections and when encountered require prompt diagnosis and initiation of specific treatment. Imaging findings are mostly nonspecific with respect to the causative pathogen. This article describes the anatomy of cranial meninges and extra-axial spaces of the brain. Characteristic findings and recent advances in neuroimaging of meningitis and its complications and ventriculitis are summarized, and certain noninfectious causes of meningitis and meningitis mimics are described.


Assuntos
Ventriculite Cerebral/diagnóstico , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Meningite/diagnóstico , Doença Aguda , Adulto , Encéfalo/patologia , Abscesso Encefálico/diagnóstico , Doenças dos Nervos Cranianos/diagnóstico , Infecção Hospitalar/diagnóstico , Diagnóstico Diferencial , Encefalocele/diagnóstico , Humanos , Lactente , Meninges/patologia , Meningite/etiologia , Valores de Referência , Punção Espinal , Vasculite do Sistema Nervoso Central/diagnóstico
11.
J Neurosurg ; 117(6): 1170-81, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23039144

RESUMO

OBJECT: Bone marrow-derived stem cells enhance the rate of regeneration of neuronal cells leading to clinical improvement in nerve injury, spinal cord injury, and brain infarction. Recent experiments in the local application of bone marrow-derived mononuclear cells (BM-MNCs) in models of sciatic nerve transection in rats have suggested their beneficial role in nerve regeneration, although the effects of variable doses of stem cells on peripheral nerve regeneration have never been specifically evaluated in the literature. In this paper, the authors evaluated the dose-dependent role of BM-MNCs in peripheral nerve regeneration in a model of sciatic nerve transection in rats. METHODS: The right sciatic nerve of 60 adult female Wistar rats (randomized into 2 test groups and 1 control group, 20 rats in each group) underwent transection under an operating microscope. The cut ends of the nerve were approximated using 2 epineural microsutures. The gap was filled with low-dose (5 million BM-MNCs/100 µl phosphate-buffered saline [PBS]) rat BM-MNCs in one group, high-dose (10 million BM-MNCs/100 µl PBS) rat BM-MNCs in another group, and only PBS in the control group, and the approximated nerve ends were sealed using fibrin glue. Histological assessment was performed after 30 days by using semiquantitative and morphometric analyses and was done to assess axonal regeneration, percentage of myelinated fibers, axonal diameter, fiber diameter, and myelin thickness at distal-most sites (10 mm from site of repair), intermediate distal sites (5 mm distal to the repair site), and site of repair. RESULTS: The recovery of nerve cell architecture after nerve anastomosis was far better in the high-dose BM-MNC group than in the low-dose BM-MNC and control groups, and it was most evident (p < 0.02 in the majority of the parameters [3 of 4]) at the distal-most site. Overall, the improvement in myelin thickness was most significant with incremental dosage of BM-MNCs, and was evident at the repair, intermediate distal, and distal-most sites (p = 0.001). CONCLUSIONS: This study emphasizes the role of BM-MNCs, which can be isolated easily from bone marrow aspirates, in peripheral nerve injury and highlights their dose-dependent facilitation of nerve regeneration.


Assuntos
Axônios , Transplante de Medula Óssea , Monócitos/transplante , Regeneração Nervosa , Nervo Isquiático/fisiopatologia , Nervo Isquiático/cirurgia , Animais , Axônios/patologia , Proliferação de Células , Feminino , Hibridização in Situ Fluorescente , Fibras Nervosas Mielinizadas , Nervos Periféricos/fisiopatologia , Nervos Periféricos/cirurgia , Distribuição Aleatória , Ratos , Ratos Wistar , Células de Schwann , Nervo Isquiático/patologia
12.
Neurol India ; 55(3): 241-50, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17921653

RESUMO

Fungal infections of the central nervous system (CNS) are rare in the general population and are invariably secondary to primary focus elsewhere, usually in the lung or intestine. Except for people with longstanding diabetes, they are most frequently encountered in immunocompromised patients such as those with acquired immunodeficiency syndrome or after organ transplantation. Due to the lack of inflammatory response, neuroradiological findings are often nonspecific and are frequently mistaken for tuberculous meningitis, pyogenic abscess or brain tumor. Intracranial fungal infections are being identified more frequently due to the increased incidence of AIDS patients, better radiological investigations, more sensitive microbiological techniques and better critical care of moribund patients. Although almost any fungus may cause encephalitis, cryptococcal meningoencephalitis is most frequently seen, followed by aspergillosis and candidiasis. The biology, epidemiology and imaging features of the common fungal infections of the CNS will be reviewed. The radiographic appearance alone is often not specific, but the combination of the appropriate clinical setting along with computed tomography or magnetic resonance may help to suggest the correct diagnosis.


Assuntos
Infecções Fúngicas do Sistema Nervoso Central/diagnóstico , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/microbiologia , Encéfalo/patologia , Infecções Fúngicas do Sistema Nervoso Central/classificação , Humanos , Medula Espinal/microbiologia , Medula Espinal/patologia
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