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1.
Crit Care ; 24(1): 382, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32600373

RESUMO

BACKGROUND: Biofilm formation on endotracheal tubes (ETTs) is an early and frequent event in mechanically ventilated patients. The biofilm is believed to act as a reservoir for infecting microorganisms and thereby contribute to development and relapses of ventilator-associated pneumonia (VAP). Once a biofilm has formed on an ETT surface, it is difficult to eradicate. This clinical study aimed to compare biofilm formation on three widely used ETTs with different surface properties and to explore factors potentially predictive of biofilm formation. METHODS: We compared the grade of biofilm formation on ETTs made of uncoated polyvinyl chloride (PVC), silicone-coated PVC, and PVC coated with noble metals after > 24 h of mechanical ventilation in critically ill patients. The comparison was based on scanning electron microscopy of ETT surfaces, biofilm grading, surveillance and biofilm cultures, and occurrence of VAP. RESULTS: High-grade (score ≥ 7) biofilm formation on the ETTs was associated with development of VAP (OR 4.17 [95% CI 1.14-15.3], p = 0.031). Compared to uncoated PVC ETTs, the silicone-coated and noble-metal-coated PVC ETTs were independently associated with reduced high-grade biofilm formation (OR 0.18 [95% CI 0.06-0.59], p = 0.005, and OR 0.34 [95% CI 0.13-0.93], p = 0.036, respectively). No significant difference was observed between silicon-coated ETTs and noble-metal-coated ETTs (OR 0.54 [95% CI 0.17-1.65], p = 0.278). In 60% of the oropharyngeal cultures and 58% of the endotracheal cultures collected at intubation, the same microorganism was found in the ETT biofilm at extubation. In patients who developed VAP, the causative microbe remained in the biofilm in 56% of cases, despite appropriate antibiotic therapy. High-grade biofilm formation on ETTs was not predicted by either colonization with common VAP pathogens in surveillance cultures or duration of invasive ventilation. CONCLUSION: High-grade biofilm formation on ETTs was associated with development of VAP. Compared to the uncoated PVC ETTs, the silicone-coated and noble-metal-coated PVC ETTs were independently associated with reduced high-grade biofilm formation. Further research on methods to prevent, monitor, and manage biofilm occurrence is needed. TRIAL REGISTRATION: ClinicalTrials.gov NCT02284438 . Retrospectively registered on 21 October 2014.


Assuntos
Biofilmes , Intubação Intratraqueal/instrumentação , Respiração Artificial/efeitos adversos , Idoso , Índice de Massa Corporal , Feminino , Humanos , Intubação Intratraqueal/efeitos adversos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Inibidores da Bomba de Prótons/administração & dosagem , Inibidores da Bomba de Prótons/uso terapêutico , Respiração Artificial/instrumentação , Respiração Artificial/métodos , Escore Fisiológico Agudo Simplificado , Suécia
2.
Biomater Sci ; 11(11): 3860-3877, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37078624

RESUMO

Tissue engineering is a promising methodology to produce advanced therapy medicinal products (ATMPs). We have developed personalized tissue engineered veins (P-TEV) as an alternative to autologous or synthetic vascular grafts utilized in reconstructive vein surgery. Our hypothesis is that individualization through reconditioning of a decellularized allogenic graft with autologous blood will prime the tissue for efficient recellularization, protect the graft from thrombosis, and decrease the risk of rejection. In this study, P-TEVs were transplanted to vena cava in pig, and the analysis of three veins after six months, six veins after 12 months and one vein after 14 months showed that all P-TEVs were fully patent, and the tissue was well recellularized and revascularized. To confirm that the ATMP product had the expected characteristics one year after transplantation, gene expression profiling of cells from P-TEV and native vena cava were analyzed and compared by qPCR and sequencing. The qPCR and bioinformatics analysis confirmed that the cells from the P-TEV were highly similar to the native cells, and we therefore conclude that P-TEV is functional and safe in large animals and have high potential for use as a clinical transplant graft.


Assuntos
Engenharia Tecidual , Veias , Animais , Suínos , Engenharia Tecidual/métodos , Veias/transplante , Células Endoteliais , Perfilação da Expressão Gênica
3.
Regen Ther ; 21: 331-341, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36110971

RESUMO

Patients with cardiovascular disease often need replacement or bypass of a diseased blood vessel. With disadvantages of both autologous blood vessels and synthetic grafts, tissue engineering is emerging as a promising alternative of advanced therapy medicinal products for individualized blood vessels. By reconditioning of a decellularized blood vessel with the recipient's own peripheral blood, we have been able to prevent rejection without using immunosuppressants and prime grafts for efficient recellularization in vivo. Recently, decellularized veins reconditioned with autologous peripheral blood were shown to be safe and functional in a porcine in vivo study as a potential alternative for vein grafting. In this study, personalized tissue engineered arteries (P-TEA) were developed using the same methodology and evaluated for safety in a sheep in vivo model of carotid artery transplantation. Five personalized arteries were transplanted to carotid arteries and analyzed for safety and patency as well as with histology after four months in vivo. All grafts were fully patent without any occlusion or stenosis. The tissue was well cellularized with a continuous endothelial cell layer covering the luminal surface, revascularized adventitia with capillaries and no sign of rejection or infection. In summary, the results indicate that P-TEA is safe to use and has potential as clinical grafts.

4.
Langmuir ; 27(2): 678-85, 2011 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-21142210

RESUMO

The aim of this work was to create patterned surfaces for localized and specific biochemical recognition. For this purpose, we have developed a protocol for orthogonal and material-selective surface modifications of microfabricated patterned surfaces composed of SiO(2) areas (100 µm diameter) surrounded by Au. The SiO(2) spots were chemically modified by a sequence of reactions (silanization using an amine-terminated silane (APTES), followed by amine coupling of a biotin analogue and biospecific recognition) to achieve efficient immobilization of streptavidin in a functional form. The surrounding Au was rendered inert to protein adsorption by modification by HS(CH(2))(10)CONH(CH(2))(2)(OCH(2)CH(2))(7)OH (thiol-OEG). The surface modification protocol was developed by testing separately homogeneous SiO(2) and Au surfaces, to obtain the two following results: (i) SiO(2) surfaces which allowed the grafting of streptavidin, and subsequent immobilization of biotinylated antibodies, and (ii) Au surfaces showing almost no affinity for the same streptavidin and antibody solutions. The surface interactions were monitored by quartz crystal microbalance with dissipation monitoring (QCM-D), and chemical analyses were performed by polarization modulation-reflexion absorption infrared spectroscopy (PM-RAIRS) and X-ray photoelectron spectroscopy (XPS) to assess the validity of the initial orthogonal assembly of APTES and thiol-OEG. Eventually, microscopy imaging of the modified Au/SiO(2) patterned substrates validated the specific binding of streptavidin on the SiO(2)/APTES areas, as well as the subsequent binding of biotinylated anti-rIgG and further detection of fluorescent rIgG on the functionalized SiO(2) areas. These results demonstrate a successful protocol for the preparation of patterned biofunctional surfaces, based on microfabricated Au/SiO(2) templates and supported by careful surface analysis. The strong immobilization of the biomolecules resulting from the described protocol is advantageous in particular for micropatterned substrates for cell-surface interactions.


Assuntos
Ouro/química , Dióxido de Silício/química , Adsorção , Biotina/química , Imunoglobulina G/química , Tamanho da Partícula , Estreptavidina/química , Propriedades de Superfície
5.
ACS Biomater Sci Eng ; 7(12): 5878-5889, 2021 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-34851620

RESUMO

Implant surface modification by nanopatterning is an interesting route for enhancing osseointegration in humans. Herein, the molecular response to an intentional, controlled nanotopography pattern superimposed on screw-shaped titanium implants is investigated in human bone. When clinical implants are installed, additional two mini-implants, one with a machined surface (M) and one with a machined surface superimposed with a hemispherical nanopattern (MN), are installed in the posterior maxilla. In the second-stage surgery, after 6-8 weeks, the mini-implants are retrieved by unscrewing, and the implant-adherent cells are subjected to gene expression analysis using quantitative polymerase chain reaction (qPCR). Compared to those adherent to the machined (M) implants, the cells adherent to the nanopatterned (MN) implants demonstrate significant upregulation (1.8- to 2-fold) of bone-related genes (RUNX2, ALP, and OC). No significant differences are observed in the expression of the analyzed inflammatory and remodeling genes. Correlation analysis reveals that older patient age is associated with increased expression of proinflammatory cytokines (TNF-α and MCP-1) on the machined implants and decreased expression of pro-osteogenic factor (BMP-2) on the nanopatterned implants. Controlled nanotopography, in the form of hemispherical 60 nm protrusions, promotes gene expressions related to early osteogenic differentiation and osteoblastic activity in implant-adherent cells in the human jaw bone.


Assuntos
Osseointegração , Osteogênese , Expressão Gênica , Humanos , Próteses e Implantes , Titânio
6.
Acta Biomater ; 136: 279-290, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34626821

RESUMO

The initial cellular and molecular activities at the bone interface of implants with controlled nanoscale topography and microscale roughness have previously been reported. However, the effects of such surface modifications on the development of osseointegration have not yet been determined. This study investigated the molecular events and the histological and biomechanical development of the bone interface in implants with nanoscale topography, microscale roughness or a combination of both. Polished and machined titanium implants with and without controlled nanopatterning (75 nm protrusions) were produced using colloidal lithography and coated with a thin titanium layer to unify the chemistry. The implants were inserted in rat tibiae and subjected to removal torque (RTQ) measurements, molecular analyses and histological analyses after 6, 21 and 28 days. The results showed that nanotopography superimposed on microrough, machined, surfaces promoted an early increase in RTQ and hence produced greater implant stability at 6 and 21 days. Two-way MANOVA revealed that the increased RTQ was influenced by microscale roughness and the combination of nanoscale and microscale topographies. Furthermore, increased bone-implant contact (BIC) was observed with the combined nanopatterned machined surface, although MANOVA results implied that the increased BIC was mainly dependent on microscale roughness. At the molecular level, the nanotopography, per se, and in synergy with microscale roughness, downregulated the expression of the proinflammatory cytokine tumor necrosis factor alpha (TNF-α). In conclusion, controlled nanotopography superimposed on microrough machined implants promoted implant stability during osseointegration. Nanoscale-driven mechanisms may involve attenuation of the inflammatory response at the titanium implant site. STATEMENT OF SIGNIFICANCE: The role of combined implant microscale and nanotopography features for osseointegration is incompletely understood. Using colloidal lithography technique, we created an ordered nanotopography pattern superimposed on screwshaped implants with microscale topography. The midterm and late molecular, bone-implant contact and removal torque responses were analysed in vivo. Nanotopography superimposed on microrough, machined, surfaces promoted the implant stability, influenced by microscale topography and the combination of nanoscale and microscale topographies. Increased bone-implant contact was mainly dependent on microscale roughness whereas the nanotopography, per se, and in synergy with microscale roughness, attenuated the proinflammatory tumor necrosis factor alpha (TNF-α) expression. It is concluded that microscale and nanopatterns provide individual as well as synergistic effects on molecular, morphological and biomechanical implant-tissue processes in vivo.


Assuntos
Osseointegração , Osteogênese , Animais , Implantes Experimentais , Ratos , Propriedades de Superfície , Titânio/farmacologia
7.
ACS Appl Bio Mater ; 4(10): 7554-7562, 2021 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-35006698

RESUMO

Both carboxylated cellulose nanofibrils (CNF) and dissolved oxygen (DO) have been reported to possess antibacterial properties. However, the combination for use as wound dressings against biofilm infections in chronic wounds is less known. The present study reports the development of oxygenated CNF dispersions that exhibit strong antibacterial effect. Carboxylated CNF dispersions with different oxidation levels were oxygenated by the OXY BIO System and tested for antibacterial activity against Pseudomonas aeruginosa and Staphylococcus aureus. The results reveal that the higher oxidation level of the CNFs, the better antibacterial effect. Scanning electron microscopy of bacterial biofilms revealed that a potential mechanism of action of the CNFs is the formation of a network surrounding and entrapping the bacteria. This effect is further potentiated by the oxygenation process. A CNF sample (concentration 0.6 wt %) that was oxygenated to a DO level of 46.4 mg/L demonstrated a strong antibacterial effect against S. aureusin vivo using a mouse model of surgical site infection. The oxygenated CNF dispersion reduced the bacterial survival by 71%, after 24 h treatment. The potent antibacterial effect indicates that oxygenated nanocellulose is a promising material for antibacterial wound dressings.


Assuntos
Bandagens , Staphylococcus aureus , Antibacterianos/farmacologia , Biofilmes , Celulose/farmacologia , Pseudomonas aeruginosa
8.
J Tissue Eng Regen Med ; 15(10): 818-830, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34318614

RESUMO

Personalized tissue engineered vascular grafts are a promising advanced therapy medicinal product alternative to autologous or synthetic vascular grafts utilized in blood vessel bypass or replacement surgery. We hypothesized that an individualized tissue engineered vein (P-TEV) would make the body recognize the transplanted blood vessel as autologous, decrease the risk of rejection and thereby avoid lifelong treatment with immune suppressant medication as is standard with allogenic organ transplantation. To individualize blood vessels, we decellularized vena cava from six deceased donor pigs and tested them for cellular removal and histological integrity. A solution with peripheral blood from the recipient pigs was used for individualized reconditioning in a perfusion bioreactor for seven days prior to transplantation. To evaluate safety and functionality of the individualized vascular graft in vivo, we transplanted reconditioned porcine vena cava into six pigs and analyzed histology and patency of the graft at different time points, with three pigs at the final endpoint 4-5 weeks after surgery. Our results showed that the P-TEV was fully patent in all animals, did not induce any occlusion or stenosis formation and we did not find any signs of rejection. The P-TEV showed rapid recellularization in vivo with the luminal surface covered with endothelial cells. In summary, the results indicate that P-TEV is functional and have potential for use as clinical transplant grafts.


Assuntos
Prótese Vascular , Estudo de Prova de Conceito , Engenharia Tecidual , Veias/fisiologia , Animais , Suínos , Grau de Desobstrução Vascular , Veias/transplante , Veias/ultraestrutura
9.
Bioengineering (Basel) ; 8(7)2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-34356204

RESUMO

Current conventional cancer drug screening models based on two-dimensional (2D) cell culture have several flaws and there is a large need of more in vivo mimicking preclinical drug screening platforms. The microenvironment is crucial for the cells to adapt relevant in vivo characteristics and here we introduce a new cell culture system based on three-dimensional (3D) printed scaffolds using cellulose nanofibrils (CNF) pre-treated with 2,2,6,6-tetramethylpyperidine-1-oxyl (TEMPO) as the structural material component. Breast cancer cell lines, MCF7 and MDA-MB-231, were cultured in 3D TEMPO-CNF scaffolds and were shown by scanning electron microscopy (SEM) and histochemistry to grow in multiple layers as a heterogenous cell population with different morphologies, contrasting 2D cultured mono-layered cells with a morphologically homogenous cell population. Gene expression analysis demonstrated that 3D TEMPO-CNF scaffolds induced elevation of the stemness marker CD44 and the migration markers VIM and SNAI1 in MCF7 cells relative to 2D control. T47D cells confirmed the increased level of the stemness marker CD44 and migration marker VIM which was further supported by increased capacity of holoclone formation for 3D cultured cells. Therefore, TEMPO-CNF was shown to represent a promising material for 3D cell culture model systems for cancer cell applications such as drug screening.

10.
Biomed Mater ; 16(4)2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34030145

RESUMO

The cancer microenvironment influences tumor progression and metastasis and is pivotal to consider when designingin vivo-like cancer models. Current preclinical testing platforms for cancer drug development are mainly limited to 2D cell culture systems that poorly mimic physiological environments and traditional, low throughput animal models. The aim of this work was to produce a tunable testing platform based on 3D printed scaffolds (3DPS) with a simple geometry that, by extracellular components and response of breast cancer reporter cells, mimics patient-derived scaffolds (PDS) of breast cancer. Here, the biocompatible polysaccharide alginate was used as base material to generate scaffolds consisting of a 3D grid containing periostin and hydroxyapatite. Breast cancer cell lines (MCF7 and MDA-MB-231) produced similar phenotypes and gene expression levels of cancer stem cell, epithelial-mesenchymal transition, differentiation and proliferation markers when cultured on 3DPS and PDS, contrasting conventional 2D cultures. Importantly, cells cultured on 3DPS and PDS showed scaffold-specific responses to cytotoxic drugs (doxorubicin and 5-fluorouracil) that were different from 2D cultured cells. In conclusion, the data presented support the use of a tunable alginate-based 3DPS as a tumor model in breast cancer drug discovery.


Assuntos
Antineoplásicos , Neoplasias da Mama/metabolismo , Impressão Tridimensional , Alicerces Teciduais/química , Microambiente Tumoral/efeitos dos fármacos , Alginatos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Medicina de Precisão , Células Tumorais Cultivadas
11.
Anal Chem ; 82(5): 2087-94, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20128623

RESUMO

Nanoplasmonic sensors based on short-range ordered nanoholes in thin metal films and discrete metal nanoparticles are known to provide similar sensing performance. However, a perforated metal film is unique in the sense that the holes can be designed to penetrate through the substrate, thereby also fulfilling the role of nanofluidic channels. This paper presents a bioanalytical sensing concept based on short-range ordered nanoplasmonic pores (diameter 150 nm) penetrating through a thin (around 250 nm) multilayer membrane composed of gold and silicon nitride (SiN) that is supported on a Si wafer. Also, a fabrication scheme that enables parallel production of multiple (more than 50) separate sensor chips or more than 1000 separate nanoplasmonic membranes on a single wafer is presented. Together with the localization of the sensitivity to within such short-range ordered nanoholes, the structure provides a two-dimensional nanofluidic network, sized in the order of 100 x 100 microm(2), with nanoplasmon active regions localized to each individual nanochannel. A material-specific surface-modification scheme was developed to promote specific binding of target molecules on the optically active gold regions only, while suppressing nonspecific adsorption on SiN. Using this protocol, and by monitoring the temporal variation in the plasmon resonance of the structure, we demonstrate flow-through nanoplasmonic sensing of specific biorecognition reactions with a signal-to-noise ratio of around 50 at a temporal resolution below 190 ms. With flow, the uptake was demonstrated to be at least 1 order of magnitude faster than under stagnant conditions, while still keeping the sample consumption at a minimum.


Assuntos
Técnicas Biossensoriais , Nanotecnologia , Limite de Detecção , Análise Espectral/métodos
12.
Analyst ; 135(2): 343-50, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20098769

RESUMO

A novel set-up combining the quartz crystal microbalance with dissipation monitoring technique (QCM-D) and electrochemical impedance spectroscopy (EIS) under flow conditions was successfully used to follow supported lipid bilayer (SLB) formation on SiO(2). This study demonstrates the simultaneous detection, in real time, of both the electrical and the structural properties of the SLB. The combination of the two techniques provided novel insights regarding the mechanism of SLB formation: we found indications for an annealing process of the lipid alkyl chains after the mass corresponding to complete bilayer coverage had been deposited. Moreover, the interaction of the SLB with the pore-forming toxin, gramicidin D (grD) was studied for grD concentrations ranging from 0.05 to 40 mg L(-1). Membrane properties were altered depending on the toxin concentration. For low grD concentrations, the electrical properties of the SLB changed upon insertion of active ion channels. For higher concentrations, the QCM-D data showed dramatic changes in the viscoelastic properties of the membrane while the EIS spectra did not change. AFM confirmed significant structural changes of the membrane at higher grD concentrations. Thus, the application of combined QCM-D and EIS detection provides complementary information about the system under study. This information will be particularly important for the continued detailed investigation of interactions at model membrane surfaces.


Assuntos
Técnicas Biossensoriais/métodos , Impedância Elétrica , Bicamadas Lipídicas/química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Quartzo/química , Eletroquímica , Dióxido de Silício/química
13.
Nucleic Acids Res ; 36(2): e10, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18063568

RESUMO

DNA microarrays are generally operated at a single condition, which severely limits the freedom of designing probes for allele-specific hybridization assays. Here, we demonstrate a fluidic device for multi-stringency posthybridization washing of microarrays on microscope slides. This device is called a multi-thermal array washer (MTAW), and it has eight individually controlled heating zones, each of which corresponds to the location of a subarray on a slide. Allele-specific oligonucleotide probes for nine mutations in the beta-globin gene were spotted in eight identical subarrays at positions corresponding to the temperature zones of the MTAW. After hybridization with amplified patient material, the slides were mounted in the MTAW, and each subarray was exposed to different temperatures ranging from 22 to 40 degrees C. When processed in the MTAW, probes selected without considering melting temperature resulted in improved genotyping compared with probes selected according to theoretical melting temperature and run under one condition. In conclusion, the MTAW is a versatile tool that can facilitate screening of a large number of probes for genotyping assays and can also enhance the performance of diagnostic arrays.


Assuntos
Análise Mutacional de DNA/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Análise de Sequência com Séries de Oligonucleotídeos/instrumentação , Sondas de Oligonucleotídeos/química , Temperatura , Genótipo , Globinas/genética , Humanos
14.
ACS Appl Bio Mater ; 3(1): 577-583, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35019401

RESUMO

Alveolar bone loss is usually treated with guided bone regeneration, a dental procedure which utilizes a tissue-separation membrane. The barrier membrane prevents pathogens and epithelial cells to invade the bone augmentation site, thereby permitting osteoblasts to deposit minerals and build up bone. This study aims at adding bioactive properties to otherwise inert PTFE membranes in order to enhance cell adherence and promote proliferation. A prewetting by ethanol and stepwise hydration protocol was herein employed to overcome high surface tension of PTFE membranes and allow for a recombinant spider silk protein, functionalized with a cell-binding motif from fibronectin (FN-silk), to self-assemble into a nanofibrillar coating. HaCaT and U-2 OS cells were seeded onto soft and hard tissue sides, respectively, of membranes coated with FN-silk. The cells could firmly adhere as early as 1 h post seeding, as well as markedly grow in numbers when kept in culture for 7 days. Fluorescence and scanning electron microscopy images revealed that adherent cells could form a confluent monolayer and develop essential cell-cell contacts during 1 week of culture. Hence, functionalized PTFE membranes have a potential of better integration at the implantation site, with reduced risk of membrane displacement as well as exposure to oral pathogens.

15.
Int Urol Nephrol ; 52(8): 1443-1451, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32172456

RESUMO

PURPOSE: Intermittent catheterization (IC) is a proven effective long-term bladder management strategy for individuals who have lower urinary tract dysfunction. This study provides clinical evidence about multiple-reuse versus single-use catheterization techniques and if catheter choice can have an impact on health-related quality of life (HRQoL). METHOD: A prospective, multi-center, clinical trial studied patients who currently practiced catheter reuse, and who agreed to prospectively evaluate single-use hydrophilic-coated (HC) (i.e. LoFric) catheters for 4 weeks. A validated Intermittent Self-Catheterization Questionnaire (ISC-Q) was used to obtain HRQoL. Reused catheters were collected and studied with regard to microbial and debris contamination. RESULTS: The study included 39 patients who had practiced IC for a mean of 10 years, 6 times daily. At inclusion, all patients reused catheters for a mean of 21 days (SD = 48) per catheter. 36 patients completed the prospective test period and the mean ISC-Q score increased from 58.0 (SD = 22.6) to 67.2 (SD = 17.7) when patients switched to the single-use HC catheters (p = 0.0101). At the end of the study, 83% (95% CI [67-94%]) preferred to continue using single-use HC catheters. All collected reused catheters (100%) were contaminated by debris and 74% (95% CI [58-87%]) were contaminated by microorganisms, some with biofilm. CONCLUSION: Single-use HC catheters improved HRQoL and were preferred over catheter reuse among people practicing IC. Catheter multiple-reuse may pose a potential safety concern due to colonization by microorganisms as well as having reduced acceptance compared to single use. TRIAL REGISTRY NUMBER: ClinicalTrials.gov NCT02129738.


Assuntos
Reutilização de Equipamento , Cateterismo Uretral Intermitente/instrumentação , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Cateterismo Uretral Intermitente/efeitos adversos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos
16.
Biomaterials ; 235: 119705, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31978840

RESUMO

Tumor cells interact with the microenvironment that specifically supports and promotes tumor development. Key components in the tumor environment have been linked to various aggressive cancer features and can further influence the presence of subpopulations of cancer cells with specific functions, including cancer stem cells and migratory cells. To model and further understand the influence of specific microenvironments we have developed an experimental platform using cell-free patient-derived scaffolds (PDSs) from primary breast cancers infiltrated with standardized breast cancer cell lines. This PDS culture system induced a series of orchestrated changes in differentiation, epithelial-mesenchymal transition, stemness and proliferation of the cancer cell population, where an increased cancer stem cell pool was confirmed using functional assays. Furthermore, global gene expression profiling showed that PDS cultures were similar to xenograft cultures. Mass spectrometry analyses of cell-free PDSs identified subgroups based on their protein composition that were linked to clinical properties, including tumor grade. Finally, we observed that an induction of epithelial-mesenchymal transition-related genes in cancer cells growing on the PDSs were significantly associated with clinical disease recurrences in breast cancer patients. Patient-derived scaffolds thus mimics in vivo-like growth conditions and uncovers unique information about the malignancy-inducing properties of tumor microenvironment.


Assuntos
Neoplasias da Mama , Linhagem Celular Tumoral , Proliferação de Células , Transição Epitelial-Mesenquimal , Humanos , Recidiva Local de Neoplasia , Células-Tronco Neoplásicas , Microambiente Tumoral
17.
Data Brief ; 31: 105860, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32637480

RESUMO

Patient-derived scaffolds (PDSs) generated from primary breast cancer tumors can be used to model the tumor microenvironment in vitro. Patient-derived scaffolds are generated by repeated detergent washing, removing all cells. Here, we analyzed the protein composition of 15 decellularized PDSs using liquid chromatography-mass spectrometry/mass spectrometry. One hundred forty-three proteins were detected and their relative abundance was calculated using a reference sample generated from all PDSs. We performed heatmap analysis of all the detected proteins to display their expression patterns across different PDSs together with pathway enrichment analysis to reveal which processes that were connected to PDS protein composition. This protein dataset together with clinical information is useful to investigators studying the microenvironment of breast cancers. Further, after repopulating PDSs with either MCF7 or MDA-MB-231 cells, we quantified their gene expression profiles using RNA sequencing. These data were also compared to cells cultured in conventional 2D conditions, as well as to cells cultured as xenografts in immune-deficient mice. We investigated the overlap of genes regulated between these different culture conditions and performed pathway enrichment analysis of genes regulated by both PDS and xenograft cultures compared to 2D in both cell lines to describe common processes associated with both culture conditions. Apart from our described analyses of these systems, these data are useful when comparing different experimental model systems. Downstream data analyses and interpretations can be found in the research article "Patient-derived scaffolds uncover breast cancer promoting properties of the microenvironment" [1].

18.
J Phys Chem B ; 112(16): 5175-81, 2008 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-18370429

RESUMO

We have investigated the effect of well-defined nanoscale topography on the 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) lipid vesicle adsorption and supported phospholipid bilayer (SPB) formation on SiO2 surfaces using a quartz crystal microbalance with dissipation monitoring (QCM-D) and atomic force microscopy (AFM). Unilamellar lipid vesicles with two different sizes, 30 and 100 nm, were adsorbed on pitted surfaces with two different pit diameters, 110 and 190 nm, as produced by colloidal lithography, and the behavior was compared to results obtained on flat surfaces. In all cases, complete bilayer formation was observed after a critical coverage of adsorbed vesicles had been reached. However, the kinetics of the vesicle-to-bilayer transformation, including the critical coverage, was significantly altered by surface topography for both vesicle sizes. Surface topography hampered the overall bilayer formation kinetics for the smaller vesicles, but promoted SPB formation for the larger vesicles. Depending on vesicle size, we propose two modifications of the precursor-mediated vesicle-to-bilayer transformation mechanism used to describe supported lipid bilayer formation on the corresponding flat surface. Our results may have important implications for various lipid-membrane-based applications using rough or topographically structured surfaces.


Assuntos
Bicamadas Lipídicas/química , Nanoestruturas/química , Fosfolipídeos/química , Dióxido de Silício/química , Cristalização , Microscopia de Força Atômica , Nanoestruturas/ultraestrutura , Propriedades de Superfície
19.
Acta Biomater ; 53: 559-571, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28232253

RESUMO

The early cell and tissue interactions with nanopatterned titanium implants are insufficiently described in vivo. A limitation has been to transfer a pre-determined, well-controlled nanotopography to 3D titanium implants, without affecting other surface parameters, including surface microtopography and chemistry. This in vivo study aimed to investigate the early cellular and molecular events at the bone interface with screw-shaped titanium implants superimposed with controlled nanotopography. Polished and machined titanium implants were firstly patterned with 75-nm semispherical protrusions. Polished and machined implants without nano-patterns were designated as controls. Thereafter, all nanopatterned and control implants were sputter-coated with a 30nm titanium layer to unify the surface chemistry. The implants were inserted in rat tibiae and samples were harvested after 12h, 1d and 3d. In one group, the implants were unscrewed and the implant-adherent cells were analyzed using quantitative polymerase chain reaction. In another group, implants with surrounding bone were harvested en bloc for histology and immunohistochemistry. The results showed that nanotopography downregulated the expression of monocyte chemoattractant protein-1 (MCP-1), at 1d, and triggered the expression of osteocalcin (OC) at 3d. This was in parallel with a relatively lower number of recruited CD68-positive macrophages in the tissue surrounding the nanopatterned implants. Moreover, a higher proportion of newly formed osteoid and woven bone was found at the nanopatterned implants at 3d. It is concluded that nanotopography, per se, attenuates the inflammatory process and enhances the osteogenic response during the early phase of osseointegration. This nanotopography-induced effect appeared to be independent of the underlying microscale topography. STATEMENT OF SIGNIFICANCE: This study provides a first line of evidence that pre-determined nanopatterns on clinically relevant, screw-shaped, titanium implants can be recognized by cells in the complex in vivo environment. Until now, most of the knowledge relating to cell interactions with nanopatterned surfaces has been acquired from in vitro studies involving mostly two-dimensional nanopatterned surfaces of varying chemical composition. We have managed to superimpose pre-determined nanoscale topography on polished and micro-rough, screw-shaped, implants, without changes in the microscale topography or chemistry. This was achieved by colloidal lithography in combination with a thin titanium film coating on top of both nanopatterned and control implants. The early events of osseointegration were evaluated at the bone interface to these implants. The results revealed that nanotopography, as such, elicits downregulatory effects on the early recruitment and activity of inflammatory cells while enhancing osteogenic activity and woven bone formation.


Assuntos
Substitutos Ósseos/química , Nanopartículas/química , Osseointegração/fisiologia , Osteoblastos/citologia , Osteoblastos/fisiologia , Tíbia/fisiologia , Titânio/química , Animais , Adesão Celular/fisiologia , Células Cultivadas , Masculino , Nanopartículas/ultraestrutura , Ratos , Ratos Sprague-Dawley , Propriedades de Superfície , Tíbia/citologia
20.
Cell Transplant ; 26(2): 293-307, 2017 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-27503828

RESUMO

Here we report the fabrication of a novel composite gel from decellularized gal-gal-knockout porcine skin and human peripheral blood mononuclear cells (hPBMCs) for full-thickness skin wound healing. Decellularized skin extracellular matrix (ECM) powder was prepared via chemical treatment, freeze drying, and homogenization. The powder was mixed with culture medium containing hyaluronic acid to generate a pig skin gel (PSG). The effect of the gel in regeneration of full-thickness wounds was studied in nude mice. We found significantly accelerated wound closure already on day 15 in animals treated with PSG only or PSG + hPBMCs compared to untreated and hyaluronic acid-treated controls (p < 0.05). Addition of the hPBMCs to the gel resulted in marked increase of host blood vessels as well as the presence of human blood vessels. At day 25, histologically, the wounds in animals treated with PSG only or PSG + hPBMCs were completely closed compared to those of controls. Thus, the gel facilitated generation of new skin with well-arranged epidermal cells and restored bilayer structure of the epidermis and dermis. These results suggest that porcine skin ECM gel together with human cells may be a novel and promising biomaterial for medical applications especially for patients with acute and chronic skin wounds.


Assuntos
Derme Acelular/metabolismo , Leucócitos Mononucleares/citologia , Pele/citologia , Pele/metabolismo , Cicatrização/fisiologia , Animais , Feminino , Imunofluorescência , Ácido Hialurônico/farmacologia , Imuno-Histoquímica , Leucócitos Mononucleares/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Pele/métodos , Suínos , Cicatrização/efeitos dos fármacos
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