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1.
J Vasc Surg Cases Innov Tech ; 10(3): 101414, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38559375

RESUMO

Transcarotid artery revascularization (TCAR) has risen as a promising minimally invasive intervention for high-risk patients with favorable anatomy. TCAR's noninferiority to carotid endarterectomy regarding stroke is reliant on its flow reversal technology and lack of aortic arch manipulation. We present the case of a 79-year-old man with a chronically occluded inferior vena cava who safely underwent staged bilateral TCAR for bilateral high-grade carotid artery stenosis. Although chronic inferior vena cava occlusion alters flow mechanics, we suspect that any pressure gradient facilitating retrograde flow from the carotid artery to the femoral vein provides neuroprotective benefits.

2.
ACS Appl Mater Interfaces ; 15(27): 32188-32200, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37350332

RESUMO

Based on cancer-related deaths, stomach cancer is ranked fifth, and first among Hispanics. Lack of technologies for early diagnosis and unavailability of target-specific therapeutics are largely the causes of the poor therapeutic outcomes from existing chemotherapeutics. Currently available therapeutic modalities are invasive and require systemic delivery, although the cancer is localized in the stomach at its early stage. Therefore, we hypothesize that an oral local delivery approach can extend the retention duration of the therapeutics modalities within the stomach and thereby enhance therapeutic efficacy. To accomplish this, we have developed a ß-glucan (BG)-based oral delivery vehicle that can adhere to the mucus lining of the stomach for an extended period while controlling the release of Bcl2 siRNA and 5-fluorouracil (5FU) payload for over 6 h. We found that Bcl2 siRNA selectively knocked down the Bcl2 gene in a C57BL/6 stomach cancer mouse model followed by upregulation of apoptosis and remission of cancer. BG was found to be very effective in maintaining the stability of siRNA for at least 6 h, when submerged in simulated gastric juice tested in vitro. To investigate the potential therapeutic effects in vivo, we used a stomach cancer mouse model, where C57BL/6 mice were treated with 5FU, BG/5FU, siRNA, BG/siRNA, and BG/5FU/siRNA. Higher inhibition of Bcl2 and therapeutic efficacy were observed in mice treated with BG/5FU/siRNA confirmed with Western blotting and a TUNEL assay. Significant reduction in the tumor region was observed with histology (H&E) and immunohistochemistry (Ki67, TUNEL, and Bcl2) analyses. Overall, the oral formulation shows improved efficacy with nonsignificant side effects compared to the conventional treatment tested in the gastric cancer mouse model.


Assuntos
Neoplasias Gástricas , beta-Glucanas , Animais , Camundongos , Fluoruracila/farmacologia , Fluoruracila/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , RNA Interferente Pequeno/genética , beta-Glucanas/uso terapêutico , Camundongos Endogâmicos C57BL
3.
Biofabrication ; 15(3)2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37160133

RESUMO

Since the first description of inkjet bioprinting of cells in 2003, quantifying the input and measuring the output of the printers has been the hallmark of the field of bioprinting, as it is virtually impossible to characterize cells that are inside the printing orifices or extrusion needles. We will describe here some recent discoveries of cell behavior due to inkjet bioprinting. Primary and immortalized adult dermal fibroblasts were expanded for 2-3 passages upon receiving. The cells were harvested, resuspended in PBS, and bioprinted into a 96-well plate with pluriSTEM media. Cells were then transferred either into precoated 96-well plates or 20µl drops were pipetted for hanging drop culture. IPC differentiation protocols were applied and the induction was begun approximately 45 min after printing. When differentiating aggregates, the initiation happened 45 min after the aggregates were transferred into the 96 wells. Standard immunostaining and RNA sequencing (RNA-Seq) were used to analyze the cell phenotypes. Preliminary results indicate that all cells expressed the three pluripotency markers oct-4, nanog, and sox-2. After applying a cardiomyocyte differentiation protocol, the cells stained positively for troponin-3. The cells also elongated and became more cardiomyocyte-like in their morphology. We analyzed bulk RNA seq data and our preliminary results show upregulation of some genes that have been implicated as stem cell markers: EPCAM, LEFTY1, ZFP42, and TEX19. In addition, differential expression of genes associated with pluripotency-relevant pathways shows some pathways are off like the MAPK/p38, MAPK/JNK1-3 which is expected for a pluripotent state. We also have data supporting the activation of the hippo pathway with transcriptional co-activator with PDZ binding motif (TAZ) highly upregulated and yes-associated protein staining the cell body. In addition, GSK3B is off and TGFB1, LIF/PIK3, and AKT1 are on as expected for pluripotency. Examining the gene network of upregulated genes, one can clearly distinguish the pivotal role of FOS, FOXO1, and PIK3 all related to pluripotency. Bioprinted fibroblasts will at least temporarily adopt a more primitive or dedifferentiated state, reminiscent of pluripotency. While immunochemistry shows the classic transcription factors required for pluripotency, gene expression shows a more nuanced picture of the transformations that occur upon printing. Understanding these transformations, even if temporary will be crucial when trying to build tissues using bioprinting technologies.


Assuntos
Bioimpressão , Bioimpressão/métodos , Fatores de Transcrição/genética , Fibroblastos , Diferenciação Celular , Fenótipo , Impressão Tridimensional
4.
ACS Appl Mater Interfaces ; 14(33): 37566-37576, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35939041

RESUMO

Chemotherapy-induced cardiac toxicity is an undesirable yet very common effect that increases the risk of death and reduce the quality of life of individuals undergoing chemotherapy. However, no feasible methods and techniques are available to monitor and detect the degree of cardiotoxicity at an early stage. Therefore, in this project, we aim to develop a fluorescent nanoprobe to image the toxicity within the cardiac tissue induced by an anticancer drug. We have observed that vascular cell adhesion molecule 1 (VCAM1) protein alone with collagen was overly expressed within the heart, when an animal was treated with doxorubicin (DOX), because of inflammation in the epithelial cells. We hypothesize that developing a VCAM1-targeted peptide-based (VHPKQHRGGSKGC) fluorescent nanoprobe can detect and visualize the affected heart. In this regard, we prepared a poly(lactic-co-glycolic acid) (PLGA) nanoparticle linked with VCAM1 peptide and rhodamine B (PLGA-VCAM1-RhB). Selective binding and higher accumulation of the PLGA-VCAM1-RhB nanoprobes were detected in DOX-treated human cardiomyocyte cells (HCMs) compared to the untreated cells. For in vivo studies, DOX (5 mg/kg) was injected via the tail vein once in two weeks for 6 weeks (3 injection total). PLGA-VCAM1-RhB and PLGA-RhB were injected via the tail vein after 1 week of the last dose of DOX, and images were taken 4 h after administration. A higher fluorescent signal of PLGA-RhB-VCAM-1 (48.62% ± 12.79%) was observed in DOX-treated animals compared to the untreated control PLGA-RhB (10.61% ± 4.90) within the heart, indicating the specificity and targeting ability of PLGA-VCAM1-RhB to the inflamed tissues. The quantified fluorescence intensity of the homogenized cardiac tissue of PLGA-RhB-VCAM1 showed 156% higher intensity than the healthy control group. We conclude that PLGA-VCAM1-RhB has the potential to bind inflamed cardiac cells, thereby detecting DOX-induced cardiotoxicity and damaged heart at an early stage.


Assuntos
Antineoplásicos , Cardiotoxicidade , Animais , Antineoplásicos/uso terapêutico , Antineoplásicos/toxicidade , Doxorrubicina/toxicidade , Humanos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Qualidade de Vida , Molécula 1 de Adesão de Célula Vascular
5.
Materials (Basel) ; 15(13)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35806588

RESUMO

The rapidly growing field of tissue engineering hopes to soon address the shortage of transplantable tissues, allowing for precise control and fabrication that could be made for each specific patient. The protocols currently in place to print large-scale tissues have yet to address the main challenge of nutritional deficiencies in the central areas of the engineered tissue, causing necrosis deep within and rendering it ineffective. Bioprinted microvasculature has been proposed to encourage angiogenesis and facilitate the mobility of oxygen and nutrients throughout the engineered tissue. An implant made via an inkjet printing process containing human microvascular endothelial cells was placed in both B17-SCID and NSG-SGM3 animal models to determine the rate of angiogenesis and degree of cell survival. The implantable tissues were made using a combination of alginate and gelatin type B; all implants were printed via previously published procedures using a modified HP inkjet printer. Histopathological results show a dramatic increase in the average microvasculature formation for mice that received the printed constructs within the implant area when compared to the manual and control implants, indicating inkjet bioprinting technology can be effectively used for vascularization of engineered tissues.

6.
Front Bioeng Biotechnol ; 10: 855186, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35360395

RESUMO

Bioprinting is an emerging technique used to layer extrudable materials and cells into simple constructs to engineer tissue or arrive at in vitro organ models. Although many examples of bioprinted tissues exist, many lack the biochemical complexity found in the native extracellular matrix. Therefore, the resulting tissues may be less competent than native tissues-this can be especially problematic for tissues that need strong mechanical properties, such as cardiac or those found in the great vessels. Decellularization of native tissues combined with processing for bioprinting may improve the cellular environment for proliferation, biochemical signaling, and improved mechanical characteristics for better outcomes. Whole porcine hearts were decellularized using a series of detergents, followed by lyophilization and mechanical grinding in order to produce a fine powder. Temperature-controlled enzymatic digestion was done to allow for the resuspension of the decellularized extracellular matrix into a pre-gel solution. Using a commercial extrusion bioprinter with a temperature-controlled printhead, a 1:1 scale model of a human ascending aorta and dog bone shaped structures were printed into a reservoir of alginate and xanthium gum then allowed to crosslink at 37C. The bioengineered aortic construct was monitored for cell adhesion, survival, and proliferation through fluorescent microscopy. The dog bone structure was subjected to tensile mechanical testing in order to determine structural and mechanical patterns for comparison to native tissue structures. The stability of the engineered structure was maintained throughout the printing process, allowing for a final structure that upheld the dimensions of the original Computer-Aided Design model. The decellularized ECM (E = 920 kPa) exhibited almost three times greater elasticity than the porcine cardiac tissue (E = 330 kPa). Similarly, the porcine cardiac tissue displayed two times the deformation than that of the printed decellularized ECM. Cell proliferation and attachment were observed during the in vitro cell survivability assessment of human aortic smooth muscle cells within the extracellular matrix, along with no morphological abnormalities to the cell structure. These observations allow us to report the ability to bioprint mechanically stable, cell-laden structures that serve as a bridge in the current knowledge gap, which could lead to future work involving complex, large-scale tissue models.

7.
Materials (Basel) ; 14(24)2021 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-34947458

RESUMO

BACKGROUND: Breast cancer (BC) continues to have the second highest mortality amongst women in the United States after lung cancer. For 2021, the American Cancer Association predicted 281,550 new invasive breast cancer cases besides 49,290 new cases of non-invasive breast cancer and 43,600 deaths from the metastatic disease. A treatment modality is radiation therapy, which is given for local control as well as palliation of patient symptoms. The initial step of new drug development is in-vitro cell studies, which help describe new drug properties and toxicities. However, these models are not optimal, and better ones have yet to be determined. This study uses bioprinting technology to elucidate the sensitivity of tumor cells to the combination of palbociclib (PD) and letrozole (Let) treatment. We hypothesize that this technology could serve as a model to predict treatment outcomes more efficiently. METHODS: The breast cancer cell lines MCF7 and MDA-MB-231 as well as the normal breast epithelial cell line, MCF-10A, were treated with PD-Let with and without radiotherapy (RT), and cell viability was compared in pairwise fashion for thermally inkjet bioprinted (TIB) and manually seeded (MS) cells. RESULTS: In absence of radiation, the TIB MCF7 cells have 2.5 times higher viability than manually seeded (MS) cells when treated with 100 µM palbociclib and 10 µM letrozole, a 36% higher viability when treated with 50 µM palbociclib and 10 µM letrozole, and an 8% higher viability when treated with 10 µM palbociclib and 10 µM letrozole. With 10 Gy of radiation, TIB cells had a 45% higher survival rate than MS cells at the lowest palbociclib concentration and a 29% higher survival rate at the intermediate palbociclib concentration. Without radiation treatment, at a concentration of 10 µM PD-Let, TIB MDA-MB-231 cells show a 8% higher viability than MS cells when treated with 10 µM PD and 10 µM Let; at higher drug concentrations, the differences disappeared, but some 1.7% of the TIB MDA-MB-231 cells survived exposure to 150 µM of PD + 10 µM letrozole vs. none of the MS cells. These cells are more radiation sensitive than the other cell lines tested and less sensitive to the combo drug treatments. We observed an 18% higher survival of TIB MCF-10A cells without radiation treatment when exposed to 10 µM PD + 10 µM Let but no difference in cell survival between the two groups when radiation was applied. Independent of growth conditions, TIB cells did not show more resistance to radiation treatment than MS cells, but a higher resistance to the combo treatment was observed, which was most pronounced in the MCF-7 cell line. CONCLUSION: Based on these results, we suggest that TIB used in in-vitro models could be a feasible strategy to develop and/or test new anticancer drugs.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32154227

RESUMO

Bioprinting technology merges engineering and biological fields and together, they possess a great translational potential, which can tremendously impact the future of regenerative medicine and drug discovery. However, the molecular effects elicited by thermal inkjet bioprinting in breast cancer cells remains elusive. Previous studies have suggested that bioprinting can be used to model tissues for drug discovery and pharmacology. We report viability, apoptosis, phosphorylation, and RNA sequence analysis of bioprinted MCF7 breast cancer cells at separate timepoints post-bioprinting. An Annexin A5-FITC apoptosis stain was used in combination with flow cytometry at 2 and 24 h post-bioprinting. Antibody arrays using a Human phospho-MAPK array kit was performed 24 h post-bioprinting. RNA sequence analysis was conducted in samples collected at 2, 7, and 24 h post-bioprinting. The post-bioprinting cell viability averages were 77 and 76% at 24 h and 48 h, with 31 and 64% apoptotic cells at 2 and 24 h after bioprinting. A total of 21 kinases were phosphorylated in the bioprinted cells and 9 were phosphorylated in the manually seeded controls. The RNA seq analysis in the bioprinted cells identified a total of 12,235 genes, of which 9.7% were significantly differentially expressed. Using a ±2-fold change as the cutoff, 266 upregulated and 206 downregulated genes were observed in the bioprinted cells, with the following 5 genes uniquely expressed NRN1L, LUCAT1, IL6, CCL26, and LOC401585. This suggests that thermal inkjet bioprinting is stimulating large scale gene alterations that could potentially be utilized for drug discovery. Moreover, bioprinting activates key pathways implicated in drug resistance, cell motility, proliferation, survival, and differentiation.

9.
Biofabrication ; 11(4): 045005, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31151129

RESUMO

One biofabrication process that has gained tremendous momentum in the field of tissue engineering and regenerative medicine is cell-printing or most commonly bioprinting. We have shown that thermal inkjet bioprinted human microvascular endothelial cells were recruited or otherwise involved in the formation of microvasculature to form graft-host anastomoses upon implantation. The present study aims to quantify and characterize the expression and activation of specific cytokines and kinases in vitro. Morphological characteristics demonstrate elongated protrusions of TIB-HMVECs at 5-6 times the size of manually pipetted cells. Moreover, annexin V-FITC and propidium iodide apoptosis assay via flow cytometry demonstrated a 75% apoptosis among printed cells as compared to among control cells. Cell viability at a 3 d incubation period was significantly higher for printed cells as compared to control. Milliplex magnetic bead panels confirmed significant overexpression of HSP70, IL-1α, VEGF-A, IL-8, and FGF-1 of printed cells compared to control. In addition, a Human phospho-kinase array displayed a significant over activation of the heat-shock proteins HSP27 and HSP60 of printed cells compared to the manually seeded cells. Collectively, it is suggested that the massive appearance of capillary blood vessels upon implantation that has been reported elsewhere may be due to the activation of the HSP-NF-κB pathway to produce VEGF. This cell activation may be used as a new strategy for vascularization of tissue engineered constructs which are in high demand in regenerative medicine applications.


Assuntos
Bioimpressão , Células Endoteliais/metabolismo , Microvasos/citologia , Transdução de Sinais , Temperatura , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Apoptose , Forma Celular , Sobrevivência Celular , Citocinas/metabolismo , Células Endoteliais/citologia , Humanos , Fosfatidilserinas/metabolismo , Fosforilação , Proteínas Quinases/metabolismo
11.
Org Biomol Chem ; 16(6): 1000-1013, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29345707

RESUMO

A 34-amino acid long collagen-like peptide rich in proline, hydroxyproline, and glycine, and with four photoreactive N-acyl-7-nitroindoline units incorporated into the peptide backbone was synthesized by on-resin fragment condensation. Its circular dichroism supports a stable triple helix structure. The built-in photochemical function enables the decomposition of the peptide into small peptide fragments by illumination with UV light of 350 nm in aqueous solution. Illumination of a thin film of the peptide, or a thin film of a photoreactive amino acid model compound containing a 5-bromo-7-nitroindoline moiety, with femtosecond laser light at 710 nm allows for the creation of well-resolved micropatterns. The cytocompatibility of the peptide was demonstrated using human mesenchymal stem cells and mouse embryonic fibroblasts. Our data show that the full-length peptide is cytocompatible as it can support cell growth and maintain cell viability. In contrast, the small peptide fragments created by photolysis are somewhat cytotoxic and therefore less cytocompatible. These data suggest that biomimetic collagen-like photoreactive peptides could potentially be used for growing cells in 2D micropatterns based on patterns generated by photolysis prior to cell growth.


Assuntos
Materiais Biomiméticos/química , Peptídeos/química , Animais , Materiais Biomiméticos/síntese química , Materiais Biomiméticos/efeitos da radiação , Materiais Biomiméticos/toxicidade , Colágeno/química , Fibroblastos/efeitos dos fármacos , Fluorescência , Humanos , Indóis/síntese química , Indóis/química , Indóis/efeitos da radiação , Indóis/toxicidade , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/toxicidade , Peptídeos/síntese química , Peptídeos/efeitos da radiação , Peptídeos/toxicidade , Raios Ultravioleta
12.
Trends Biotechnol ; 36(4): 384-402, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29137814

RESUMO

Biofabrication holds the potential to generate constructs that more closely recapitulate the complexity and heterogeneity of tissues and organs than do currently available regenerative medicine therapies. Such constructs can be applied for tissue regeneration or as in vitro 3D models. Biofabrication is maturing and growing, and scientists with different backgrounds are joining this field, underscoring the need for unity regarding the use of terminology. We therefore believe that there is a compelling need to clarify the relationship between the different concepts, technologies, and descriptions of biofabrication that are often used interchangeably or inconsistently in the current literature. Our objective is to provide a guide to the terminology for different technologies in the field which may serve as a reference for the biofabrication community.


Assuntos
Materiais Biocompatíveis , Medicina Regenerativa , Terminologia como Assunto , Engenharia Tecidual , Animais , Humanos , Hidrogéis/química , Microfluídica , Modelos Animais , Polímeros/química , Impressão Tridimensional , Esferoides Celulares/química
13.
Curr Opin Ophthalmol ; 27 Suppl 1: 3-47, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28099212

RESUMO

Dysfunctional tear syndrome (DTS) is a common and complex condition affecting the ocular surface. The health and normal functioning of the ocular surface is dependent on a stable and sufficient tear film. Clinician awareness of conditions affecting the ocular surface has increased in recent years because of expanded research and the publication of diagnosis and treatment guidelines pertaining to disorders resulting in DTS, including the Delphi panel treatment recommendations for DTS (2006), the International Dry Eye Workshop (DEWS) (2007), the Meibomian Gland Dysfunction (MGD) Workshop (2011), and the updated Preferred Practice Pattern guidelines from the American Academy of Ophthalmology pertaining to dry eye and blepharitis (2013). Since the publication of the existing guidelines, new diagnostic techniques and treatment options that provide an opportunity for better management of patients have become available. Clinicians are now able to access a wealth of information that can help them obtain a differential diagnosis and treatment approach for patients presenting with DTS. This review provides a practical and directed approach to the diagnosis and treatment of patients with DTS, emphasizing treatment that is tailored to the specific disease subtype as well as the severity of the condition.


Assuntos
Síndromes do Olho Seco , Doenças Palpebrais/fisiopatologia , Glândulas Tarsais/fisiopatologia , Lágrimas/fisiologia , Blefarite/diagnóstico , Blefarite/fisiopatologia , Blefarite/terapia , Síndromes do Olho Seco/diagnóstico , Síndromes do Olho Seco/fisiopatologia , Síndromes do Olho Seco/terapia , Humanos , Ceratoconjuntivite Seca/diagnóstico , Ceratoconjuntivite Seca/fisiopatologia , Ceratoconjuntivite Seca/terapia
14.
BMC Proc ; 11(Suppl 12): 12, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29375655

RESUMO

BACKGROUND AND PURPOSE: With funding from the National Institutes of Health, BUILDing SCHOLARS was established at The University of Texas at El Paso with the goal of implementing, evaluating and sustaining a suite of institutional, faculty and student development interventions in order to train the next generation of biomedical researchers from the U.S. Southwest region, where the need is dire among underserved communities. The focus is on supporting the infrastructure necessary to train and mentor students so they persist on pathways across a range of biomedical research fields. The purpose of this article is to highlight the design and implementation of BUILDing SCHOLARS' key interventions, which offer a systemic student training model for the U.S. Southwest. In-depth reporting of evaluation results is reserved for other technical publications. PROGRAM AND KEY HIGHLIGHTS: BUILDing SCHOLARS uses a comprehensive regional approach to undergraduate training through a multi-institution consortium that includes 12 research partners and various pipeline partners across Texas, New Mexico, and Arizona. Through faculty collaborations and undergraduate research training, the program integrates social and behavioral sciences and biomedical engineering while emphasizing seven transdisciplinary nodes of biomedical research excellence that are common across partner institutions: addiction, cancer, degenerative and chronic diseases, environmental health, health disparities, infectious diseases, and translational biomedicine. Key interventions aim to: (1) improve institutional capacities by expanding undergraduate research training infrastructures; (2) develop an intra- and cross-institutional mentoring-driven "community of practice" to support undergraduate student researchers; (3) broaden the pool of student participants, improve retention, and increase matriculation into competitive graduate programs; and (4) support faculty and postdoctoral personnel by training them in research pedagogy and mentoring techniques and providing them with resources for increasing their research productivity. Student training activities focus on early interventions to maximize retention and on enabling students to overcome common barriers by addressing their educational endowments, science socialization, network development, family expectations, and material resources. Over the long term, BUILDing SCHOLARS will help increase the diversity of the biomedical research workforce in the U.S. by meeting the needs of students from the Southwest region and by serving as a model for other institutions.

15.
Artigo em Inglês | MEDLINE | ID: mdl-32318317

RESUMO

A new molecular imprinting technique was developed for molecularly imprinted polymer particles (MIPs). Particles were synthesized using organic silane chemistries by a sol-gel process, where the relative amount of active monomers was complementary matched to the relative amount of surface charges of the West Nile antibody template. Synthesized MIPs showed specific binding to affinity purified polyclonal West Nile antibodies (WNA) with a loading capacity of 80 µg/mg, while MIPs absorbed non-specific proteins at a loading capacity of 28 µg/mg. A dissociation constant of Kd=57.45 µM was measured from the binding isotherms. MIPs selectively absorbed 27 times more WNA than either albumin or immunoglobulin, while MIPs absorbed 16 times more WNA than non- imprinted particles (NIPs). Finally, fluorescently labeled MIPs were incubated in a high bind 96 well plate previously loaded with template, albumin, or immunoglobulin as an immunoassay test. Fluorescent MIPs significantly bound more to wells with WNA than any other control. Thus, the development of new affordable and robust immunoassays with MIPs would be possible in the future.

16.
Biomed Opt Express ; 7(11): 4654-4659, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27896004

RESUMO

N-acyl-7-nitroindolines have been used as caged compounds to photorelease active molecules by a one- or two-photon excitation mechanism in biological systems. Here, we report the photolysis of a polypeptide that contains 7-nitroindoline units as linker moieties in its peptide backbone for potential materials engineering applications. Upon two-photon excitation with femtosecond laser light at 710 nm the photoreactive amide bond in N-peptidyl-7-nitroindolines is cleaved rendering short peptide fragments. Thus, this photochemical process changes the molecular composition at the laser focal volume. Gel modifications of this peptide can potentially be used for three-dimensional microstructure fabrication.

17.
Biofabrication ; 8(1): 013001, 2016 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-26744832

RESUMO

Biofabrication is an evolving research field that has recently received significant attention. In particular, the adoption of Biofabrication concepts within the field of Tissue Engineering and Regenerative Medicine has grown tremendously, and has been accompanied by a growing inconsistency in terminology. This article aims at clarifying the position of Biofabrication as a research field with a special focus on its relation to and application for Tissue Engineering and Regenerative Medicine. Within this context, we propose a refined working definition of Biofabrication, including Bioprinting and Bioassembly as complementary strategies within Biofabrication.


Assuntos
Órgãos Bioartificiais/tendências , Materiais Biocompatíveis/síntese química , Produtos Biológicos/síntese química , Materiais Biomiméticos/síntese química , Impressão Tridimensional/tendências , Engenharia Tecidual/tendências , Terminologia como Assunto
18.
Biotechnol J ; 11(3): 393-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26710125

RESUMO

Many new biomedical approaches to treating disease require the supply of cells delivered to an injured or diseased organ either individually, collectively as aggregates or sheets, or encapsulated with a scaffold. The collection of cells is accomplished by using enzymatic digestion witch suffer from the need to remove the enzymes after digestion. In addition, enzymatic methods are not applicable for all cells, cell aggregates, cell sheets or 3D structures. The objective of this study was to investigate the release of cultured cells from silicon based Photovoltaic (PV) surfaces using a light source as external stimulation. C2C12 myoblasts were cultured on the negative surface of a PV device and upon confluence they were exposed to light. The amount of released cells was quantified as a function light exposure. It was found that light exposure at 25,000 lux for one hour caused equivalent cell release from the PV surface than trypsination. The released cells are viable and can be re-cultured if needed. This mechanism may offer an alternative method to release excitable cells without using an enzymatic agent. This may be important for cell therapy if larger cell structures such as sheets need to be collected.


Assuntos
Técnicas de Cultura de Células/instrumentação , Mioblastos/citologia , Animais , Técnicas de Cultura de Células/métodos , Linhagem Celular , Sobrevivência Celular , Luz , Silício/química , Propriedades de Superfície
19.
Tissue Eng Part A ; 21(1-2): 224-33, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25051339

RESUMO

Chronic wounds such as diabetic foot ulcers and venous leg ulcers are common problems in people suffering from type 2 diabetes. These can cause pain, and nerve damage, eventually leading to foot or leg amputation. These types of wounds are very difficult to treat and sometimes take months or even years to heal because of many possible complications during the process. Allogeneic skin grafting has been used to improve wound healing, but the majority of grafts do not survive several days after being implanted. We have been studying the behavior of fibroblasts and keratinocytes in engineered capillary-like endothelial networks. A dermo-epidermal graft has been implanted in an athymic nude mouse model to assess the integration with the host tissue as well as the wound healing process. To build these networks into a skin graft, a modified inkjet printer was used, which allowed the deposit of human microvascular endothelial cells. Neonatal human dermal fibroblast cells and neonatal human epidermal keratinocytes were manually mixed in the collagen matrix while endothelial cells printed. A full-thickness wound was created at the top of the back of athymic nude mice and the area was covered by the bilayered graft. Mice of the different groups were followed until completion of the specified experimental time line, at which time the animals were humanely euthanized and tissue samples were collected. Wound contraction improved by up to 10% when compared with the control groups. Histological analysis showed the neoskin having similar appearance to the normal skin. Both layers, dermis and epidermis, were present with thicknesses resembling normal skin. Immunohistochemistry analysis showed favorable results proving survival of the implanted cells, and confocal images showed the human cells' location in the samples that were collocated with the bilayer printed skin graft.


Assuntos
Microvasos/fisiologia , Transplante de Pele , Pele/patologia , Engenharia Tecidual/métodos , Cicatrização , Animais , Bovinos , Cicatriz/patologia , Epiderme/patologia , Humanos , Imuno-Histoquímica , Masculino , Camundongos Nus
20.
JAMA Ophthalmol ; 131(1): 17-22, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23307204

RESUMO

OBJECTIVE: To compare the clinical sensitivity and specificity of the AdenoPlus test with those of both viral cell culture (CC) with confirmatory immunofluorescence assay (IFA) and polymerase chain reaction (PCR) at detecting the presence of adenovirus in tear fluid. METHODS: A prospective, sequential, masked, multicenter clinical trial enrolled 128 patients presenting with a clinical diagnosis of acute viral conjunctivitis from a combination of 8 private ophthalmology practices and academic centers. Patients were tested with AdenoPlus, CC-IFA, and PCR to detect the presence of adenovirus. MAIN OUTCOME MEASURES: The sensitivity and specificity of AdenoPlus were assessed for identifying cases of adenoviral conjunctivitis. RESULTS: Of the 128 patients enrolled, 36 patients' results were found to be positive by either CC-IFA or PCR and 29 patients' results were found to be positive by both CC-IFA and PCR. When compared only with CC-IFA, AdenoPlus showed a sensitivity of 90% (28/31) and specificity of 96% (93/97). When compared only with PCR, AdenoPlus showed a sensitivity of 85% (29/34) and specificity of 98% (89/91). When compared with both CC-IFA and PCR, AdenoPlus showed a sensitivity of 93% (27/29) and specificity of 98% (88/90). When compared with PCR, CC-IFA showed a sensitivity of 85% (29/34) and specificity of 99% (90/91). CONCLUSION: AdenoPlus is sensitive and specific at detecting adenoviral conjunctivitis. APPLICATION TO CLINICAL PRACTICE: An accurate and rapid in-office test can prevent the misdiagnosis of adenoviral conjunctivitis that leads to the spread of disease, unnecessary antibiotic use, and increased health care costs. Additionally, AdenoPlus may help a clinician make a more informed treatment decision regarding the use of novel therapeutics. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00921895.


Assuntos
Infecções por Adenovirus Humanos/diagnóstico , Adenovírus Humanos/isolamento & purificação , Conjuntivite Viral/diagnóstico , Técnicas de Diagnóstico Oftalmológico , Lágrimas/virologia , Doença Aguda , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/genética , Adenovírus Humanos/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos Virais/análise , Criança , Pré-Escolar , Conjuntivite Viral/virologia , DNA Viral/análise , Método Duplo-Cego , Reações Falso-Positivas , Feminino , Imunofluorescência , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase/métodos , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Cultura de Vírus/métodos , Adulto Jovem
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