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1.
Violence Against Women ; 26(1): 66-88, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30791833

RESUMEN

Prevention of sexual violence among young people has become a priority area in Ghana, although few initiatives have focused on this topic. The ADAPT-ITT (Assessment, Decisions, Administration, Production, Topical experts, Integration, Training staff, and Testing) framework was used to systematically adapt an evidence-based sexual violence prevention program developed in the United States to a university in Ghana. Results from cognitive interviews, focus groups, beta testing, and topical experts indicate the adapted primary prevention program is promising for use in Ghanaian universities. To our knowledge, this is the first study that has used the ADAPT-ITT framework for a sexual violence program.

2.
Platelets ; 31(1): 68-78, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-30810440

RESUMEN

Despite the transient hyporeactivity of neonatal platelets, full-term neonates do not display a bleeding tendency, suggesting potential compensatory mechanisms which allow for balanced and efficient neonatal hemostasis. This study aimed to utilize small-volume, whole blood platelet functional assays to assess the neonatal platelet response downstream of the hemostatic platelet agonists thrombin and adenosine diphosphate (ADP). Thrombin activates platelets via the protease-activated receptors (PARs) 1 and 4, whereas ADP signals via the receptors P2Y1 and P2Y12 as a positive feedback mediator of platelet activation. We observed that neonatal and cord blood-derived platelets exhibited diminished PAR1-mediated granule secretion and integrin activation relative to adult platelets, correlating to reduced PAR1 expression by neonatal platelets. PAR4-mediated granule secretion was blunted in neonatal platelets, correlating to lower PAR4 expression as compared to adult platelets, while PAR4 mediated GPIIb/IIIa activation was similar between neonatal and adult platelets. Under high shear stress, cord blood-derived platelets yielded similar thrombin generation rates but reduced phosphatidylserine expression as compared to adult platelets. Interestingly, we observed enhanced P2Y1/P2Y12-mediated dense granule trafficking in neonatal platelets relative to adults, although P2Y1/P2Y12 expression in neonatal, cord, and adult platelets were similar, suggesting that neonatal platelets may employ an ADP-mediated positive feedback loop as a potential compensatory mechanism for neonatal platelet hyporeactivity.

3.
J Biomed Mater Res B Appl Biomater ; 108(1): 30-37, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30883023

RESUMEN

Bacterial cellulose is one of the most promising polymers of recent years. Herein, we present a possibility of BC application as a carrier of gentamycin antibiotic for the treatment and prevention of bone infections. We have shown that BC saturated with gentamycin significantly reduces the level of biofilm-forming bone pathogens, namely Staphylococcus aureus and Pseudomonas aeruginosa, and displays very low cytotoxicity in vitro against osteoblast cell cultures. Another beneficial feature of our prototype dressing is prolonged release of gentamycin, which provides efficient protection from microbial contamination and subsequent infection. Moreover, it seems that bacterial cellulose (BC) alone without any antimicrobial added, may serve as a barrier by significantly hampering the ability of the pathogen to penetrate to the bone structure. Therefore, a gentamycin-saturated BC dressing may be considered as a possible alternative for gentamycin collagen sponge broadly used in clinical setting. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:30-37, 2020.

4.
J Biomed Mater Res B Appl Biomater ; 108(1): 22-29, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30884116

RESUMEN

Beta-tricalcium phosphate granular cement (ß-TCP GC), consisting of ß-TCP granules and an acidic calcium phosphate (Ca-P) solution, shows promise in the reconstruction of bone defects as it sets to form interconnected porous structures, that is, ß-TCP granules are bridged with dicalcium phosphate dihydrate (DCPD) crystals. In this study, the effects of acidic Ca-P solution concentration (0-600 mmol/L) on the setting reaction and tissue response to ß-TCP GC were investigated. The ß-TCP GC set upon mixing with its liquid phase, based on the formation of DCPD crystals, which bridged ß-TCP granules to one another. Diametral tensile strength of the set ß-TCP GC was relatively the same, at ∼0.6 MPa, when the Ca-P concentration was 20-600 mmol/L. Due to the setting ability, reconstruction of the rat's calvarial bone defect using ß-TCP GC with 20, 200, and 600 mmol/L Ca-P solution was much easier compared to that with ß-TCP granules without setting ability. Four weeks after the reconstruction, the amount of new bone was the same, ∼17% in both ß-TCP GC and ß-TCP granules groups. Cellular response to ß-TCP granules and ß-TCP GC using the 20 mmol/L acidic Ca-P solution was almost the same. However, ß-TCP GC using the 200 and 600 mmol/L acidic Ca-P solution showed a more severe inflammatory reaction. It is concluded, therefore, that ß-TCP GC, using the 20 mmol/L acidic Ca-P solution, is recommended as this concentration allows surgical techniques to be performed easily and provides good mechanical strength, and the similar cellular response to ß-TCP granules. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:22-29, 2020.

5.
J Biomed Mater Res B Appl Biomater ; 108(1): 48-55, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30888115

RESUMEN

Surgical outcome following pelvic organ prolapse (POP) repair needs improvement. We suggest a new approach based on a tissue-engineering strategy. In vivo, the regenerative potential of an electrospun biodegradable polycaprolactone (PCL) mesh was studied. Six different biodegradable PCL meshes were evaluated in a full-thickness abdominal wall defect model in 84 rats. The rats were assigned into three groups: (1) hollow fiber PCL meshes delivering two dosages of basic fibroblast growth factor (bFGF), (2) solid fiber PCL meshes with and without bFGF, and (3) solid fiber PCL meshes delivering connective tissue growth factor (CTGF) and rat mesenchymal stem cells (rMSC). After 8 and 24 weeks, we performed a histological evaluation, quantitative analysis of protein content, and the gene expression of collagen-I and collagen-III, and an assessment of the biomechanical properties of the explanted meshes. Multiple complications were observed except from the solid PCL-CTGF mesh delivering rMSC. Hollow PCL meshes were completely degraded after 24 weeks resulting in herniation of the mesh area, whereas the solid fiber meshes were intact and provided biomechanical reinforcement to the weakened abdominal wall. The solid PCL-CTGF mesh delivering rMSC demonstrated improved biomechanical properties after 8 and 24 weeks compared to muscle fascia. These meshes enhanced biomechanical and biochemical properties, demonstrating a great potential of combining tissue engineering with stem cells as a new therapeutic strategy for POP repair. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:48-55, 2020.

6.
J Biomed Mater Res B Appl Biomater ; 108(1): 38-47, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30893513

RESUMEN

Natural bone microstructure has shown to be the most efficient choice for the bone scaffold design. However, there are several process parameters involved in the generation of a microCT-based 3D-printed (3DP) bone. In this study, the effect of selected parameters on the reproducibility of mechanical properties of a 3DP trabecular bone structure is investigated. MicroCT images of a distal radial sample were used to reconstruct a 3D ROI of trabecular bone. Nine tensile tests on bulk material and 54 compression tests on 8.2 mm cubic samples were performed (9 cases × 6 specimens/case). The effect of input-image resolution, STL mesh decimation, boundary condition, support material, and repetition parameters on the weight, elastic modulus, and strength were studied. The elastic modulus and the strength of bulk material showed consistent results (CV% = 9 and 6%, respectively). The weight, elastic modulus, and strength of the cubic samples showed small intragroup variation (average CV% = 1.2, 9, and 5.5%, respectively). All studied parameters had a significant effect on the outcome variables with less effect on the weight. Utmost care to every step of the 3DP process and involved parameters is required to be able to reach the desired mechanical properties in the final printed specimen. © 2019 The Authors. Journal of Biomedical Materials Research Part B: Applied Biomaterials published by Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:38-47, 2020.

7.
J Biomed Mater Res B Appl Biomater ; 108(1): 14-21, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30893515

RESUMEN

The purpose is to estimate the oxygen diffusion coefficient and the relaxation time of the cornea with respect to the oxygen tension at the cornea-tears interface. Both findings are discussed. From the experimental data provided by Bonanno et al., the oxygen tension measurements in vivo for human cornea-tears-contact lens (CL), the relaxation time of the cornea, and their oxygen diffusion coefficient were obtained by numerical calculation using the Monod-kinetic model. Our results, considering the relaxation time of the cornea, observe a different behavior. At the time less than 8 s, the oxygen diffusivity process is upper-diffusive, and for the relaxation time greater than 8 s, the oxygen diffusivity process is lower-diffusive. Both cases depend on the partial pressure of oxygen at the entrance of the cornea. The oxygen tension distribution in the cornea-tears interface is separated into two different zones: one for conventional hydrogels, which is located between 6 and 75 mmHg, with a relaxation time included between 8 and 19 s, and the other zone for silicone hydrogel CLs, which is located at high oxygen tension, between 95 and 140 mmHg, with a relaxation time in the interval of 1.5-8 s. It is found that in each zone, the diffusion coefficient varies linearly with the oxygen concentration, presenting a discontinuity in the transition of 8 s. This could be interpreted as an aerobic-to-anaerobic transition. We attribute this behavior to the coupling formalism between oxygen diffusion and biochemical reactions to produce adenosine triphosphate. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:14-21, 2020.

8.
J Biomed Mater Res B Appl Biomater ; 108(1): 73-79, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30895727

RESUMEN

Here, a prototypical metallic nanoglass is proposed as a new alloy for balloon expandable stents. Traditionally, the stainless steel SS 316L alloy has been used as a preferred material for this application due to its proper combination of mechanical properties, corrosion resistance, and biocompatibility. Recently, metallic glasses (MGs) have been considered as promising materials for biodevice applications. MGs often display outstanding mechanical properties superior to those of conventional metallic alloys and overcome some of the weaknesses of SS 316L, such as radiopacity, stainless steel allergy, and thrombosis-induced restenosis. However, commonly used monolithic MGs, which have an amorphous homogeneous microstructure, suffer from lack of ductility that is necessary for deployment of balloon expandable stents. In contrast, nanoglasses, that is, amorphous alloys with heterogeneous microstructure, exhibit enhanced ductility which makes them promising materials for balloon expandable stents. We evaluate the feasibility of a prototypical Zr64 Cu36 nanoglass with a grain size of 5 nm for balloon expandable stents by performing finite element method modeling of the stent deployment process in a coronary artery. We consider the BX-Velocity stent design and the nanoglass mechanical properties calculated from atomistic simulations. The results suggest that nanoglasses are suitable materials for balloon expandable stent applications. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:73-79, 2020.

9.
J Health Care Chaplain ; 26(1): 1-15, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-30896345

RESUMEN

As many hospitals lack standardized referral protocols for spiritual care, healthcare professionals' perceptions and preferences play an important role in their decisions to refer patients to chaplains. To better understand what motivates these professionals to refer patients and how they approach spiritual care, this article examines referral requests from twelve healthcare professionals to a chaplain at the Lausanne University Hospital Department of Physical and Rehabilitation Medicine. Comparative discourse analysis highlights that requests are largely driven by difficulties in patient-professional relationships. Yet, further interviews reveal that healthcare professionals construct spiritual care as a way to access patients' sense of identity and explore the meaning they give to their lives and experiences, for the benefit of both patients and professionals. The discussion considers how chaplains could help healthcare colleagues formulate referrals that accurately reflect patients' spiritual needs, thus improving the relevance and quality of spiritual care.

10.
J Biomed Mater Res B Appl Biomater ; 108(1): 174-182, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30950569

RESUMEN

The application of strontium is one option for the clinical treatment of osteoporosis-a disease characterized by reduced bone density and quality-in order to reduce the risk of vertebral and nonvertebral fractures. Unlike other drugs used in osteoporosis therapy, strontium shows a dual effect on bone metabolism by attenuating cellular resorption and simultaneously enhancing new bone tissue formation. Current concerns regarding the systemic application of highly dosed strontium ranelate led to the development of strontium-modified scaffolds based on mineralized collagen (MCM) capable to release biologically active Sr2+ ions directly at the fracture site. In this study, we investigated the regenerative potential of these scaffolds. For in vitro investigations, human mesenchymal stromal cells were cultivated on the scaffolds for 21 days (w/ and w/o osteogenic supplements). Biochemical analysis revealed a significant promoting effect on proliferation rate and osteogenic differentiation on strontium-modified scaffolds. In vivo, scaffolds were implanted in a murine segmental bone defect model-partly additionally functionalized with the osteogenic growth factor bone morphogenetic protein 2 (BMP-2). After 6 weeks, bridging calluses were obtained in BMP-2 functionalized scaffolds; the quality of the newly formed bone tissue by means of morphological scores was clearly enhanced in strontium-modified scaffolds. Histological analysis revealed increased numbers of osteoblasts and blood vessels, decreased numbers of osteoclasts, and significantly enhanced mechanical properties. These results indicate that the combined release of Sr2+ ions and BMP-2 from the biomimetic scaffolds is a promising strategy to enhance bone regeneration, especially in patients suffering from osteoporosis. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:174-182, 2020.

11.
Eur J Cancer Prev ; 29(1): 42-52, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30950925

RESUMEN

Preclinical studies have suggested the antitumorigenic properties of metformin on prostate cancer; results from epidemiological studies remain contradictory. We aim to investigate the evidence of metformin and the risk of prostate cancer. PubMed, Embase, Cochrane Library, and Web of Science databases were searched for eligible studies. Meta-analyses were carried out using the most fully adjusted hazard ratios and the corresponding 95% confidence intervals. Eighteen cohort studies and six case-control studies representing 2 009 504 male patients with type 2 diabetes mellitus were identified. The pooled HR of prostate cancer for metformin therapy was 0.97 (0.84-1.12) in case-control studies and 0.94 (0.79-1.12) in cohort studies, respectively. In cohort studies, we found that there was a modest association in studies with samples from Europe, but not in studies with samples from North America, Asia, and Oceania. In addition, metformin showed a slightly protective effect compared with sulfonylurea, but not insulin and other comparators. Meta-regression analyses found that obesity and prostate-specific antigen adjustment in statistical models may be the sources of heterogeneity. However, there were no significant differences in subgroups stratified by time-related biases, analytical approaches, types of risk estimates, study quality, publication year, and whether adjusted for smoking, alcohol abuse, hemoglobin A1c, diabetes duration, and other confounding factors. Our study showed that metformin therapy was not associated with the risk of prostate cancer in patients with type 2 diabetes mellitus. However, exploratory analyses suggest that metformin use may be protective in a certain subgroup of patients.

12.
J Biomed Mater Res B Appl Biomater ; 108(1): 143-155, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30957425

RESUMEN

This study is to investigate the effect of synthesis approaches on morphology, porosity, and biocompatibility of bioactive glass (BG). BG prepared through sol-gel approach was subsequently subjected to microwave and probe sonication techniques to investigate the structural and morphological effect. Hexagonal rod-shaped morphology was obtained in sol-gel-derived bioactive glass, whereas mesoporous particles and spherical-shaped morphology were observed in probe-sonicated and microwave-assisted sol-gel approaches, respectively. The probe-sonicated BG has mesopores with pore diameter of 14.7 nm, whereas surface porosity of 1.5 nm, and 3.5 nm for pure sol-gel and microwave-assisted sol-gel fabricated BGs. Granular size, shape, and porosity have a significant role at the point of contact with cellular membrane. Therefore, we studied the biocompatibility with respect to morphology and porosity of the fabricated BGs. From this study, we observed that the BG prepared using probe sonication method controls the particle size, further it enhances the porosity that altogether improves the biocompatibility. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:143-155, 2020.

13.
J Biomed Mater Res B Appl Biomater ; 108(1): 192-200, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30957435

RESUMEN

The importance of tissue engineering has been established as a promising approach in treating neurodegenerative diseases. The purpose of the current study is to determine the effect of fibrin hydrogel on the differentiation of iPSC into oligodendrocyte. For this purpose, iPSCs transduced by miR-338 expressing lentiviruses. They were treated with basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), and platelet-derived growth factor (PDGF)-AA. The process was traced by a 6-day treatment in a mitogen-free medium. At the end of the process, multipolar preoligodendrocytes appeared. In comparison to tissue culture plate (TCP), MTT assay demonstrated a significant increase in the viability of cells cultured in fibrin hydrogel. SEM analysis showed cells with elongated morphology and intertwined intercellular interactions. An immunofluorescent assay confirmed the expression of oligodendrocyte markers Olig2 and O4. In comparison to TCP, real-time PCR data indicated a significant increase in the expression of some markers such as Olig2, MBP, Sox10, and PDGFRα on cells encapsulated in fibrin hydrogel. Overall, the results suggest that fibrin hydrogel improves viability of cells and promotes the differentiation of iPSCs into preoligodendrocytes. Hence, it can be used as an appropriate option in the tissue engineering in order to treat neurodegenerative diseases. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:192-200, 2020.

14.
J Biomed Mater Res B Appl Biomater ; 108(1): 234-242, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30957437

RESUMEN

In our previous studies, we found that adult stem cells transfected with sex-determining region Y-box (SOX)-9, -6 and -5 genes (SOX trio) enhanced chondrogenesis and suppressed the progression of osteoarthritis (OA). The inhibition of angiopoietin-like 4 (ANGPT4) is known to reduce levels of cartilage damaging enzymes, such as, matrix metalloproteinases (MMPs). In this study, we designed nanoparticles comprising dexamethasone-conjugated polyethylenimine (DEX PEI) complexed with minicircle plasmid (MC) harboring SOX duo (SOX-9, -6) and ANGPTL4 small hairpin RNA (shANG) [MC SOX9/6/shANG] in the expectation that transfection of these nanoparticles would enhance chondrogenesis of stem cells and suppress inflammation in OA. Adipose-derived stem cells (ADSCs) transfected with MC SOX9/6/shANG (MC SOX9/6/shANG-tADSCs) showed significantly higher expressions of COL2 gene and protein than MC SOX9/6-transfected ADSCs (MC SOX9/6-tADSCs) during in vitro chondrogenesis while both enhanced chondrogenesis in the absence of growth factor addition as compared with negative controls. Furthermore, the expressions of MMP13 and MMP3 genes were significantly more diminished in MC SOX9/6/shANG-tADSCs than in MC SOX9/6-tADSCs. In vivo experiments using surgically-induced OA rats showed MC SOX9/6/shANG-tADSC-treated rats had significantly lower levels of cyclooxygenase (COX-2) and MMP13 in synovial fluids than MC SOX9/6-tADSC-treated rats, but no significant difference was observed between them in histological appearances. Both groups showed significantly less joint destruction than control groups did. These results demonstrate that dual functional nanoparticles containing SOX duo and ANGPT4 shRNA enhance chondrogenesis of ADSCs and suppress inflammation in OA. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:234-242, 2020.

15.
J Biomed Mater Res B Appl Biomater ; 108(1): 201-212, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30957440

RESUMEN

Dental biomaterials have revolutionized modern therapies. Untreated dental caries remains the major etiological factor for endodontic treatment, and together with a decreasing rate of tooth loss escalates the importance of continuously improving the materials used for endodontic therapies. Endodontic biomaterials are used for vital pulp therapies, irrigation, intracanal medicaments, obturation and regenerative procedures. These materials offer several functions including: antimicrobial activity, mechanical reinforcement, aesthetics, and therapeutic effects. Vital pulp therapies have seen an improvement in clinical results with an incremental approach to build on the strengths of past materials such as calcium hydroxide and calcium silicates. While sodium hypochlorite remains the gold standard for canal irrigation, numerous nanoparticle formulations have been developed to promote sustained antimicrobial action. Gutta-percha based bulk fillers remain the most common materials for root filling. However, while multiple studies focus on the development of novel formulations containing drugs, glass derivatives or ionic-, polymeric-, or drug- loaded nanoparticles, a lack of reliable and long-term clinical evidence obligates further study as experienced clinicians prefer to use what has worked for decades. This review delves in to the biochemistry of the materials to scrutinize their shortcomings, and where opportunity lies to further enhance their efficacy in endodontic practice. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:201-212, 2020.

16.
J Biomed Mater Res B Appl Biomater ; 108(1): 167-173, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30957969

RESUMEN

In this study, a degradable magnesium alloy WE43 (Mg-3.56%Y-2.20%Nd-0.47%Zr) was used as a research object. To refine its microstructure from the initial homogenized one, the alloy was subjected to severe plastic deformation (SPD) by equal channel angular pressing (ECAP). The data presented show that coincubation of tumor LNCaP and MDA-MB-231 cells with the WE43 alloy in the homogenized and the ECAP-processed states led to a decrease in their viability and proliferation. An increase in the concentration of Annexin V(+) cells during coincubation with samples in both microstructural states investigated was also observed. This is associated with the induction of apoptosis in the cell culture through contact with the samples. Concurrently, a significant drop in the concentration of Bcl-2(+) cells occurred. It was established that ECAP led to an enhancement of the cytotoxic activity of the alloy against tumor cells. This study demonstrated that alloy WE43 can be considered as a promising candidate for application in orthopedic implants in clinical oncology, where it could play a double role of a mechanically stable, yet bioresorbable, scaffold with local antitumor activity. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:167-173, 2020.

17.
J Biomed Mater Res B Appl Biomater ; 108(1): 183-191, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30957972

RESUMEN

The aim of this study was to evaluate the effects of three different chemotherapeutic agents, following air-abrasive debridement, on surface chemical properties and cytocompatibility. Disks contaminated with Streptococcus gordonii biofilm were treated with air-abrasion and immersion in either 0.9% NaCl (Air + NaCl), 0.05% alkaline electrolyzed water (AEW) (Air + AEW), or 3% H2 O2 (Air + H2 O2 ). Noncontaminated and untreated titanium disks served as a control (As-polished). The efficacy of biofilm removal, magnitude of initial cytocompatibility toward human bone marrow mesenchymal stem cells, and surface chemical properties were determined. In all treatment groups, biofilms containing microorganisms were observed to be completely removed. The data showed discrepancies for cell affinities among treatment groups, whereby: (1) the number of cells attached to the Air + AEW treated surfaces was approximately two times greater than that to the Air + NaCl treated surfaces; and (2) cell spreading was significantly enhanced on the Air + AEW treated surfaces compared with the Air + NaCl or Air + H2 O2 treated surfaces. X-ray photoelectron spectroscopy data showed that the mean relative concentrations of nitrogen to titanium on the As-polished, Air + NaCl, Air + AEW, and Air + H2 O2 surfaces were 0.0079, 0.0237, 0.0071, and 0.0210, respectively, which would provide a clear understanding that these discrepancies could be attributed to sufficient removals of organic-nitrogen deposits at the same magnitude as the As-polished following the Air + AEW treatment. This study clarifies that chemical surface treatment with AEW, as an adjunctive to air-abrasive debridement may be beneficial in restoring surface properties for tissue integration. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:183-191, 2020.

18.
J Biomed Mater Res B Appl Biomater ; 108(1): 213-224, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30964600

RESUMEN

Rapid endothelialization of cardiovascular stents is critical to prevent major clinical complications such as restenosis. Reconstruction of the native endothelium on the stent surface can be achieved by the capture of endothelial progenitor cells (EPCs) or neighboring endothelial cells (ECs) in vivo. In this study, stainless steel cardiovascular stents were functionalized with recombinant scFv antibody fragments specific for vascular endothelial growth factor receptor-2 (VEGFR2) that is expressed on EPCs and ECs. Anti-VEGFR2 scFvs were expressed in glycosylated form in Escherichia coli and covalently attached to amine-functionalized, titania-coated steel disks and stents. ScFv-coated surfaces exhibited no detectable cytotoxicity to human ECs or erythrocytes in vitro and bound 15 times more VEGFR2-positive human umbilical vein ECs than controls after as little as 3 min. Porcine coronary arteries were successfully stented with scFv-coated stents with no adverse clinical events after 30 days. Endovascular imaging and histology revealed coverage of the anti-VEGFR2 scFv-coated stent with a cell layer after 5 days and the presence of a neointima layer with a minimum thickness of 80 µm after 30 days. Biofunctionalization of cardiovascular stents with endothelial cell-capturing antibody fragments in this manner offers promise in accelerating stent endothelialization in vivo. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:213-224, 2020.

19.
Eur J Cancer Prev ; 29(1): 15-26, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30964753

RESUMEN

The association between physical activity (PA) and colorectal cancer (CRC) patients' survival is inconsistent. We conducted a systematic review and meta-analysis to summarize published articles on this issue. We performed a comprehensive search of the PubMed, Embase, and Web of Science databases for relevant articles through 28 February 2018. The summary hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using a random-effects model. Eighteen prospective cohort studies were included in the meta-analysis, with a total of 9257 cases of total mortality (TM) and 4015 cases of colorectal cancer-specific mortality (CRCSM) among 31 873 CRC survivors and 557 150 general populations. Among CRC survivors, the highest versus the lowest levels of prediagnosis PA showed decreased risks of TM (summary HR = 0.81, 95% CI: 0.76-0.87, I = 1.8%) and CRCSM (summary HR = 0.85, 95% CI: 0.77-0.98, I = 0), respectively. Significant risk reductions for TM and CRCSM were also demonstrated for postdiagnosis PA (HR = 0.63, 95% CI: 0.54-0.74; and HR = 0.64, 95% CI: 0.47-0.88, respectively). The inverse association between prediagnosis PA and cancer mortality was more pronounced for colon cancer than that for rectal cancer (P = 0.08). The summary HRs (95% CIs) of TM were 0.89 (0.83-0.97) and 0.79 (0.69-0.90) per 10 metabolic equivalent task-h/week increase in prediagnosis and postdiagnosis PA, respectively. Our meta-analysis provides comprehensive evidence that PA performed before or after cancer diagnosis is related to reduced mortality risk among CRC survivors.

20.
J Biomed Mater Res B Appl Biomater ; 108(1): 94-103, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30974041

RESUMEN

Improving the surface properties of vascular stents to accelerate endothelialization in vivo could play an important role in minimizing the risk of late thrombosis. We previously showed that mussel adhesive protein fused with VE-cadherin extracellular domain (VE-M) specifically triggered endothelial cell adhesion in vitro. In this study, using stent implants coated with VE-M, we evaluated the clinical applicability of VE-M in endothelialization recovery in vivo. First, we explored the effect of VE-M on hemocompatibility and tight junctions between endothelial cells (ECs) in vitro. VE-M significantly inhibited platelet adhesion and promoted EC proliferation. Furthermore, VE-M drastically increased the centralization of F-actin in human umbilical vein endothelial cells (HUVECs) along the cell contacts, reduced fluorescein isothiocyanate (FITC)-dextran transport across the HUVECs, and elevated expression levels of tight junction proteins (TJPs) in ECs. We then evaluated the effect of VE-M on endothelialization recovery in vivo through implantation of vascular stents. At 1 day after implantation, stents coated with VE-M recruited more endothelial progenitor cells (EPCs) than bare stents. At 7 days after implantation, VE-M stents had a greater coverage of ECs than bare stents. At 1 month after implantation, ECs on VE-M stents were appropriately elliptical in morphology and closely resembled physiological morphology. Hematoxylin-eosin (HE) staining revealed little in-stent neointima formation on VE-M stents, and SEM images revealed that smooth endothelium had formed on VE-M stents without adherent platelets. Taken together, these findings indicate that VE-M accelerates in vivo endothelialization of vascular stents via recruitment of EPCs and promotes endothelium formation and could be explored as a potential bioactive coating for vascular implant. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:94-103, 2020.

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