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1.
Biomater Adv ; 153: 213568, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37591177

ABSTRACT

Alternative engineering approaches have led the design of implants with controlled physical features to minimize adverse effects in biological tissues. Similar efforts have focused on optimizing the design features of percutaneous VAD drivelines with the aim to prevent infection, omitting however a thorough look on the implant-skin interactions that govern local tissue reactions. Here, we utilized an integrated approach for the biophysical modification of transdermal implants and their evaluation by chronic sheep implantation in comparison to the standard of care VAD drivelines. We developed a novel method for the transfer of breath topographical features on thin wires with modular size. We examined the impact of implant's diameter, surface topography, and chemistry on macroscopic, histological, and physical markers of inflammation, fibrosis, and mechanical adhesion. All implants demonstrated infection-free performance. The fibrotic response was enhanced by the increasing diameter of implants but not influenced by their surface properties. The implants of small diameter promoted mild inflammatory responses with improved mechanical adhesion and restricted epidermal downgrowth, in both silicone and polyurethane coated transdermal wires. On the contrary, the VAD drivelines with larger diameter triggered severe inflammatory reactions with frequent epidermal downgrowth. We validated these effects by quantifying the infiltration of macrophages and the level of vascularization in the fibrotic zone, highlighting the critical role of size reduction for the benign integration of transdermal implants with skin. This insight on how the biophysical properties of implants impact local tissue reactions could enable new solutions on the transdermal transmission of power, signal, and mass in a broad range of medical devices.


Subject(s)
Body Fluids , Drug-Related Side Effects and Adverse Reactions , Animals , Sheep , Skin , Epidermis , Biophysics
2.
J Prosthet Dent ; 130(1): 48-58, 2023 Jul.
Article in English | MEDLINE | ID: mdl-34809995

ABSTRACT

STATEMENT OF PROBLEM: Different techniques for retrieving cement-retained implant-supported prostheses have been described to minimize damage to the prostheses. Nevertheless, a classification of the described techniques remains ambiguous. PURPOSE: The purpose of this systematic review was to review and classify the described techniques for recording and locating the screw access hole in cement-retained implant-supported prostheses. MATERIAL AND METHODS: A bibliographic search was completed on MEDLINE/PubMed, Web of Science, Scopus, and Cochrane databases. A manual search was also conducted. The articles that described or evaluated techniques for recording and locating the screw access hole of cement-retained implant-supported prostheses were included. Two investigators independently assessed the quality assessment of the studies using the Revised Cochrane risk of bias tool for randomized trials. A third examiner was consulted to resolve the lack of consensus. RESULTS: A total of 30 articles were included. The different methods were classified according to whether the screw access hole location was registered before or after cementation. The precementation techniques were classified into 4 subgroups: identification marks, photographic records, digital files, and precementation screw access hole location guides. The postcementation techniques were subdivided into 2 subgroups: radiographic records and postcementation screw access hole location guides. CONCLUSIONS: Different techniques have been proposed to facilitate the location of the screw access hole in cement-retained implant-supported restorations. Although the evidence is scarce, studies seem to ascertain that some techniques, such as the use of drilling guides, orientation with cone beam computed tomography images, or holes made in the metal framework, can increase the retrievability of cement-retained implant-supported prostheses and decrease complications in the location of the screw access hole. The proposed classification summarizes precementation and postcementation techniques and provides a tool to decide the most suitable for each specific clinical situation.


Subject(s)
Dental Implants , Dental Prosthesis, Implant-Supported/methods , Dental Prosthesis Retention/methods , Dental Cements/therapeutic use , Cementation/methods , Glass Ionomer Cements , Bone Screws
4.
ACS Appl Mater Interfaces ; 14(3): 3643-3652, 2022 Jan 26.
Article in English | MEDLINE | ID: mdl-35006666

ABSTRACT

We here present a micropatterning strategy to introduce small molecules and ligands on patterns of arbitrary shapes on the surface of poly(acrylamide)-based hydrogels. The main advantages of the presented approach are the ease of use, the lack of need to prefabricate photomasks, the use of mild UV light and biocompatible bioconjugation chemistries, and the capacity to pattern low-molecular-weight ligands, such as peptides, peptidomimetics, or DNA fragments. To achieve the above, a monomer containing a caged amine (NVOC group) was co-polymerized in the hydrogel network; upon UV light illumination using a commercially available setup, primary amines were locally deprotected and served as reactive groups for further functionalization. Cell patterning on various cell adhesive ligands was demonstrated, with cells responding to a combination of pattern shape and substrate elasticity. The approach is compatible with standard traction force microscopy (TFM) experimentation and can further be extended to reference-free TFM.

5.
Epilepsy Res ; 178: 106812, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34844092

ABSTRACT

OBJECTIVE: To analyze the prevalence of antiseizure medication (ASM) in patients with brain metastasis-related epilepsy (BMRE) treated with radiosurgery and the relationship between ASM and psychiatric comorbidity. MATERIAL AND METHODS: This is a cross-sectional observational design study with retrospective review of medical records of all patients with brain metastases treated with volumetric modulated arc therapy radiosurgery (VMAT-RS) between 2012 and 2018 in a tertiary oncology center. We included those patients with BMRE, analyzing the clinical and demographic data, with special attention to psychiatric comorbidities and the use of ASM. RESULTS: Of the 121 patients with brain metastases included for treatment with VMAT-RS, a total of 38 presented BMRE. The most widely used ASM as first-line treatment was levetiracetam (89%). Only 8% of the patients received sodium channel blockers. The most common psychiatric comorbidity was depression (42.1%). CONCLUSIONS: Levetiracetam is the most widely used ASM in patients with BMRE treated with VMAT-RS. Nevertheless, common psychiatric comorbidities in this population might change the decision-making of ASM choice.


Subject(s)
Brain Neoplasms , Epilepsy , Anticonvulsants/therapeutic use , Brain Neoplasms/complications , Brain Neoplasms/drug therapy , Cross-Sectional Studies , Epilepsy/drug therapy , Epilepsy/epidemiology , Humans , Retrospective Studies
6.
Mol Ther ; 29(2): 636-644, 2021 02 03.
Article in English | MEDLINE | ID: mdl-33010231

ABSTRACT

We evaluated the administration of ARI-0001 cells (chimeric antigen receptor T cells targeting CD19) in adult and pediatric patients with relapsed/refractory CD19+ malignancies. Patients received cyclophosphamide and fludarabine followed by ARI-0001 cells at a dose of 0.4-5 × 106 ARI-0001 cells/kg, initially as a single dose and later split into 3 fractions (10%, 30%, and 60%) with full administration depending on the absence of cytokine release syndrome (CRS). 58 patients were included, of which 47 received therapy: 38 with acute lymphoblastic leukemia (ALL), 8 with non-Hodgkin's lymphoma, and 1 with chronic lymphocytic leukemia. In patients with ALL, grade ≥3 CRS was observed in 13.2% (26.7% before versus 4.3% after the amendment), grade ≥3 neurotoxicity was observed in 2.6%, and the procedure-related mortality was 7.9% at day +100, with no procedure-related deaths after the amendment. The measurable residual disease-negative complete response rate was 71.1% at day +100. Progression-free survival was 47% (95% IC 27%-67%) at 1 year: 51.3% before versus 39.5% after the amendment. Overall survival was 68.6% (95% IC 49.2%-88%) at 1 year. In conclusion, the administration of ARI-0001 cells provided safety and efficacy results that are comparable with other academic or commercially available products. This trial was registered as ClinicalTrials.gov: NCT03144583.


Subject(s)
Antigens, CD19/immunology , Immunotherapy, Adoptive , Neoplasms/immunology , Neoplasms/therapy , Receptors, Chimeric Antigen/immunology , T-Lymphocytes/immunology , Cell- and Tissue-Based Therapy , Drug Resistance, Neoplasm , Female , Humans , Male , Neoplasm Grading , Neoplasm Staging , Neoplasms/pathology , Recurrence , T-Lymphocytes/metabolism
7.
Front Immunol ; 11: 482, 2020.
Article in English | MEDLINE | ID: mdl-32528460

ABSTRACT

Development of semi-automated devices that can reduce the hands-on time and standardize the production of clinical-grade CAR T-cells, such as CliniMACS Prodigy from Miltenyi, is key to facilitate the development of CAR T-cell therapies, especially in academic institutions. However, the feasibility of manufacturing CAR T-cell products from heavily pre-treated patients with this system has not been demonstrated yet. Here we report and characterize the production of 28 CAR T-cell products in the context of a phase I clinical trial for CD19+ B-cell malignancies (NCT03144583). The system includes CD4-CD8 cell selection, lentiviral transduction and T-cell expansion using IL-7/IL-15. Twenty-seven out of 28 CAR T-cell products manufactured met the full list of specifications and were considered valid products. Ex vivo cell expansion lasted an average of 8.5 days and had a mean transduction rate of 30.6 ± 13.44%. All products obtained presented cytotoxic activity against CD19+ cells and were proficient in the secretion of pro-inflammatory cytokines. Expansion kinetics was slower in patient's cells compared to healthy donor's cells. However, product potency was comparable. CAR T-cell subset phenotype was highly variable among patients and largely determined by the initial product. TCM and TEM were the predominant T-cell phenotypes obtained. 38.7% of CAR T-cells obtained presented a TN or TCM phenotype, in average, which are the subsets capable of establishing a long-lasting T-cell memory in patients. An in-depth analysis to identify individual factors contributing to the optimal T-cell phenotype revealed that ex vivo cell expansion leads to reduced numbers of TN, TSCM, and TEFF cells, while TCM cells increase, both due to cell expansion and CAR-expression. Overall, our results show for the first time that clinical-grade production of CAR T-cells for heavily pre-treated patients using CliniMACS Prodigy system is feasible, and that the obtained products meet the current quality standards of the field. Reduced ex vivo expansion may yield CAR T-cell products with increased persistence in vivo.


Subject(s)
Immunotherapy, Adoptive/methods , T-Lymphocyte Subsets/immunology , T-Lymphocytes/immunology , Academic Medical Centers , Adolescent , Adult , Automation , Bioreactors , Cell Proliferation , Cells, Cultured , Child , Cytotoxicity, Immunologic , Female , Humans , Immunologic Memory , Male , Point-of-Care Systems , Young Adult
9.
J Clin Med ; 8(10)2019 Oct 17.
Article in English | MEDLINE | ID: mdl-31627401

ABSTRACT

Calcium phosphate materials are widely used as bone substitutes due to their bioactive and biodegradable properties. Also, the presence of silicon in their composition seems to improve the bioactivity of the implant and promote bone tissue repair. The aim of this study was to develop a novel ceramic scaffold by partial solid-state sintering method with a composition lying in the field of the Nurse's A-phase-silicocarnotite, in the tricalcium phosphate-dicalcium silicate (TCP-C2S) binary system. Also, we evaluated its osteogenic and osteoconductive properties after being implanted into tibia defects in New Zealand rabbits. X-ray, microcomputer tomography, and histomorphometry studies demonstrated that this porous ceramic is highly biocompatible and it has excellent osteointegration. The material was being progressively reabsorbed throughout the study and there was no unspecified local or systemic inflammatory response observed. These results suggest that ceramic imitates the physicochemical characteristics of bone substitutes used in bone reconstruction.

10.
Medicine (Baltimore) ; 97(41): e12228, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30313025

ABSTRACT

To assess the quality of life (QoL) of treated patients in order to evaluate the success of peripheral transluminal angioplasty (PTA) and correlate physical parameters with clinical progress at 6 months post-PTA.According to TASC II classifications, 69 patients were selected for PTA. Clinical evaluation and diagnostic tests were performed before, after and after 6 months following PTA. The SF-36 QoL questionnaire was added as an additional parameter.Fifty one patients were included in the study. The ankle-brachial index (ABI) increased from 0.49 ±â€Š0.11 before PTA, to 0.81 ±â€Š0.14 after PTA (P < .001) and 0.76 ±â€Š0.10 at 6 months following PTA (P < .001). Transcutaneous oxygen pressure (TcPO2) increased from 28.05 ±â€Š3.15 mm Hg before PTA, to 39.89 ±â€Š4.12 after PTA (P < .001) and 46.4 ±â€Š3.81 at 6 months following PTA (P < .001). The lumen of the affected blood vessel increased from 29 ±â€Š18% before PTA, to 81 ±â€Š10.3% after PTA (P < .001). SF-36 values increased from 29 ±â€Š18 before PTA, to 81 ±â€Š10.36 at 6 months following PTA (P < .001).The improvement of QoL is the parameter that best describes the symptoms and functionality of the patient, therefore, should be used to determine the successful PTA. Although ABI and TcPO2 with arteries functionality and tissue oxygenation, they are not show a significant correlation with all parameters determined in the QoL questionnaire.


Subject(s)
Angioplasty , Diabetic Angiopathies/therapy , Intermittent Claudication/therapy , Quality of Life , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Intermittent Claudication/etiology , Male , Middle Aged , Treatment Outcome
11.
J Med Phys ; 42(3): 133-139, 2017.
Article in English | MEDLINE | ID: mdl-28974858

ABSTRACT

INTRODUCTION: The aim of this work is to verify the use of radiochromic film in the quality assurance (QA) of volumetric-modulated arc therapy (VMAT) lung stereotactic body radiation therapy (SBRT) plans and compare the results with those obtained using an ion chamber array. MATERIALS AND METHODS: QA was performed for 14 plans using a two-dimensional-array seven29 and EBT3 film. Dose values per session ranged between 7.5 Gy and 18 Gy. The multichannel method was used to obtain a dose map for film. RESULTS: The results obtained were compared with treatment planning system calculated profiles through gamma analysis. Passing criteria were 3%/3 mm, 2%/2 mm and 3%/1.5 mm with maximum and local dose (LD) normalization. Mean gamma passing rate (GPR) (percentage of points presenting a gamma function value of <1) was obtained and compared. Calibration curves were obtained for each color channel within the dose range 0-16 Gy. Mean GPR values for film were >98.9% for all criteria when normalizing per maximum dose. When using LD, normalization was >92.7%. GPR values for the array were lower for all criteria; this difference being statistically significant when normalizing at LD, reaching 12% for the 3%/1.5 mm criterion. CONCLUSION: Both detectors provide satisfactory results for the QA of plans for VMAT lung SBRT. The film provided greater mean GPR values, afforded greater spatial resolution and was more efficient overall.

12.
Eur J Cancer ; 64: 167-74, 2016 09.
Article in English | MEDLINE | ID: mdl-27428073

ABSTRACT

BACKGROUND: Autologous tumour lysate dendritic cell vaccine (ADC) has T-cell stimulatory capacity and, therefore, potential antitumour activity. We designed a phase II randomised trial of ADC + best supportive care (BSC) (experimental arm [EA]) compared with BSC (control arm [CA]), in pre-treated metastatic colorectal cancer (mCRC) patients. PATIENTS AND METHODS: Patients with progressive mCRC, at least to two chemotherapy regimens and Eastern Cooperative Oncology Group performance status (ECOG PS) 0-2, were randomised to EA versus CA. Stratification criteria: ECOG PS (0-1 versus 2) and lactate dehydrogenase (ULN). EA was administered subcutaneously till progressive disease. Primary end-point was progression-free survival (PFS) at 4 months. RESULTS: Fifty-two patients were included (28 EA/24 CA). An interim analysis recommended early termination for futility. No objective radiological response was observed in EA. Median PFS in EA was 2.7 months (95% confidence interval [CI], 2.3-3.2 months) versus 2.3 months (95% CI, 2.1-2.5 months) in CA (p = 0.628). Median overall survival (OS) was 6.2 months (95% CI, 4.4-7.9 months) in EA versus 4.7 months (95% CI, 2.3-7 months) in CA (p = 0.41). No ADC-related adverse events were reported. Immunization induces tumour-specific T-cell response in 21 of 25 (84%) patients. Responder patients have an OS of 7.3 months (95% CI, 5.2-9.4 months) versus 3.8 months (95% CI, 0.6-6.9 months) in non-responders; p = 0.026). CONCLUSION: Our randomised clinical trial comparing ADC + BSC versus BSC in mCRC demonstrates that ADC generates a tumour-specific immune response but not benefit on PFS and OS. Our results do not support the use of ADC alone, in a phase III trial.


Subject(s)
Cancer Vaccines/administration & dosage , Colorectal Neoplasms/therapy , Dendritic Cells/immunology , Adult , Aged , Aged, 80 and over , Cancer Vaccines/immunology , Cell Line, Tumor , Colorectal Neoplasms/immunology , Colorectal Neoplasms/pathology , Colorectal Neoplasms/secondary , Female , Humans , Immunotherapy/methods , Male , Middle Aged , Multivariate Analysis , Survival Analysis
13.
Int J Gynecol Cancer ; 25(1): 12-7, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25365589

ABSTRACT

OBJECTIVE: Current evidence suggests that the presence of tumor-initiating cells (TICs) in epithelial ovarian cancer (EOC) has a role in chemoresistance and relapse. Surface markers such as CD44(+)/CD24(-), CD117(+), and CD133(+) expression have been reported as potential markers for TICs related to ovarian cancer and tumorigenic cell lines. In this study, we have investigated if spheroid forms are TIC specific or whether they can also be produced by somatic stem cells from healthy tissue in vitro. In addition, we also investigated the specificity of surface markers to identify TICs from papillary serous EOC patients. METHODS: Cells were obtained from fresh tumors from 10 chemotherapy-naive patients with EOC, and cells from ovarian and tubal epithelium were obtained from 5 healthy menopausal women undergoing surgery for benign pathology and cultured in standard and in selective medium. Cells forming nonadherent spheroids were considered TICs, and the adherent cells were considered as non-TIC-like. Percentages of CD24(+), CD44(+), CD117(+), CD133(+), and vascular endothelial growth factor receptor (VEGF-R)(+) cell surface markers were analyzed by flow cytometry. RESULTS: Four of 10 EOC cell tissues were excluded from the study. Tumor cells cultured in selective medium developed spheroid forms after 1 to 7 weeks in 5 of 6 EOC patients. No spheroid forms were observed in cultures of cells from healthy women. Unlike previously published data, low levels of CD24(+), CD44(+), CD117(+), and VEGF-R(+) expression were observed in spheroid cells, whereas expression of CD133(+) was moderate but higher in adherent cells from papillary serous EOC cells in comparison with adherent cells from controls. CONCLUSIONS: Papillary serous EOC contains TICs that form spheroids with low expression of CD44(+), CD24(+), CD117(+) and VEGF-R(+). Further research is required to find specific surface markers to identify papillary serous TICs.


Subject(s)
Cystadenocarcinoma, Serous/pathology , Neoplasm Recurrence, Local/pathology , Neoplastic Stem Cells/pathology , Ovarian Neoplasms/pathology , Ovary/pathology , Spheroids, Cellular/pathology , Adult , Aged , Aged, 80 and over , Antigens, CD/metabolism , Biomarkers, Tumor/metabolism , Case-Control Studies , Cells, Cultured , Cystadenocarcinoma, Serous/metabolism , Female , Flow Cytometry , Follow-Up Studies , Humans , Middle Aged , Neoplasm Recurrence, Local/metabolism , Neoplasm Staging , Neoplastic Stem Cells/metabolism , Ovarian Neoplasms/metabolism , Ovary/metabolism , Pilot Projects , Prognosis , Spheroids, Cellular/metabolism , Vascular Endothelial Growth Factor A/metabolism
14.
J Med Phys ; 39(4): 219-24, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25525309

ABSTRACT

It is widely accepted that a redundant independent dose calculation (RIDC) must be included in any treatment planning verification procedure. Specifically, volumetric modulated arc therapy (VMAT) technique implies a comprehensive quality assurance (QA) program in which RIDC should be included. In this paper, the results obtained in 1 year of clinical experience are presented. Eclipse from Varian is the treatment planning system (TPS), here in use. RIDC were performed with the commercial software; Diamond(®) (PTW) which is capable of calculating VMAT fields. Once the plan is clinically accepted, it is exported via Digital Imaging and Communications in Medicine (DICOM) to RIDC, together with the body contour, and then a point dose calculation is performed, usually at the isocenter. A total of 459 plans were evaluated. The total average deviation was -0.3 ± 1.8% (one standard deviation (1SD)). For higher clearance the plans were grouped by location in: Prostate, pelvis, abdomen, chest, head and neck, brain, stereotactic radiosurgery, lung stereotactic body radiation therapy, and miscellaneous. The highest absolute deviation was -0.8 ± 1.5% corresponding to the prostate. A linear fit between doses calculated by RIDC and by TPS produced a correlation coefficient of 0.9991 and a slope of 1.0023. These results are very close to those obtained in the validation process. This agreement led us to consider this RIDC software as a valuable tool for QA in VMAT plans.

15.
PLoS One ; 9(11): e113090, 2014.
Article in English | MEDLINE | ID: mdl-25402503

ABSTRACT

OBJECTIVE: CD5 plays a crucial role in autoimmunity and is a well-established genetic risk factor of developing RA. Recently, evidence of positive selection has been provided for the CD5 Pro224-Val471 haplotype in East Asian populations. The aim of the present work was to further analyze the functional relevance of non-synonymous CD5 polymorphisms conforming the ancestral and the newly derived haplotypes (Pro224-Ala471 and Pro224-Val471, respectively) as well as to investigate the potential role of CD5 on the development of SLE and/or SLE nephritis. METHODS: The CD5 SNPs rs2241002 (C/T; Pro224Leu) and rs2229177 (C/T; Ala471Val) were genotyped using TaqMan allelic discrimination assays in a total of 1,324 controls and 681 SLE patients of Spanish origin. In vitro analysis of CD3-mediated T cell proliferative and cytokine response profiles of healthy volunteers homozygous for the above mentioned CD5 haplotypes were also analyzed. RESULTS: T-cell proliferation and cytokine release were significantly increased showing a bias towards to a Th2 profile after CD3 cross-linking of peripheral mononuclear cells from healthy individuals homozygous for the ancestral Pro224-Ala471 (CC) haplotype, compared to the more recently derived Pro224-Val471 (CT). The same allelic combination was statistically associated with Lupus nephritis. CONCLUSION: The ancestral Ala471 CD5 allele confers lymphocyte hyper-responsiveness to TCR/CD3 cross-linking and is associated with nephritis in SLE patients.


Subject(s)
CD5 Antigens/genetics , Haplotypes/genetics , Lupus Erythematosus, Systemic/genetics , Lupus Nephritis/etiology , Lymphocyte Activation/immunology , Polymorphism, Genetic/genetics , T-Lymphocytes/immunology , Alleles , Autoimmunity/immunology , Case-Control Studies , Genetic Predisposition to Disease , Genotype , Humans , Lupus Erythematosus, Systemic/complications , Lupus Erythematosus, Systemic/immunology , Lupus Nephritis/diagnosis
16.
FEBS Lett ; 588(17): 2805-13, 2014 Aug 25.
Article in English | MEDLINE | ID: mdl-24945728

ABSTRACT

CD6 is a lymphocyte glycoprotein receptor that physically associates with the antigen-specific receptor complex at the center of the immunological synapse, where it interacts with its ligand CD166/ALCAM. The present work reports the carbohydrate-dependent interaction of CD6 and CD166/ALCAM with Galectin-1 and -3, two well-known soluble mammalian lectins. Both galectins interfered with superantigen-induced T cell proliferation and cell adhesion phenomena mediated by the CD6-CD166/ALCAM pair, while CD6 expression protected cells from galectin-induced apoptosis. The results suggest that interaction of Galectin-1 and -3 with CD6 and CD166/ALCAM might modulate some relevant aspects of T cell physiology.


Subject(s)
Activated-Leukocyte Cell Adhesion Molecule/metabolism , Antigens, CD/metabolism , Antigens, Differentiation, T-Lymphocyte/metabolism , Galectin 1/metabolism , Galectin 3/metabolism , Apoptosis , B-Lymphocytes/cytology , Carbohydrate Metabolism , Cell Adhesion , Cell Membrane/metabolism , Dendritic Cells/immunology , Humans , Protein Binding , Superantigens/immunology , T-Lymphocytes/cytology , T-Lymphocytes/immunology
17.
Clin Oral Investig ; 17(1): 147-58, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22323056

ABSTRACT

OBJECTIVES: The pineal gland hormone, melatonin, is an immunomodulator and neuroendocrine hormone; it also stimulates monocyte, cytokine and fibroblast proliferations, which influence angiogenesis. The aim of this study was to investigate the effects of melatonin on angiogenesis during bone defect repair by means of radiological and histomorphometric evaluations of bone response to melatonin implants. MATERIALS AND METHODS: Twenty New Zealand rabbits weighing 3,900-4,500 g were used. Twenty melatonin implants were inserted in the proximal metaphyseal area of the animals' right tibia and 20 control areas were located in the left proximal metaphyseal area. Following implantation, the animals were sacrificed in groups of five, after 1, 2, 3 and 4 weeks, respectively. Anteroposterior and lateral radiographs were taken, and radiographic thermal imaging analysis was performed for all groups at different time stages following implant insertion. Samples were sectioned at 5 µm and stained using Hematoxylin-Eosin and Masson's trichrome, supplementing radiographic findings with histomorphometric analysis. RESULTS: After 4 weeks, radiological images showed complete repair of the bone defects. No healed or residual bone alterations attributable to the presence of the melatonin implant were observed. Histomorphometric analysis at 4 weeks showed the presence of a higher density newly formed bone. There were statistically significant differences in the length of cortical formation between the melatonin group and the control group during the first weeks of the study; there were also statistically significant differences in the number of vessels observed in the melatonin groups at the first two study stages. CONCLUSION AND CLINICAL RELEVANCE: Melatonin may have potential beneficial effects on bone defect repair.


Subject(s)
Angiogenesis Inducing Agents/pharmacology , Bone Remodeling/drug effects , Melatonin/pharmacology , Neovascularization, Physiologic/drug effects , Tibia/drug effects , Animals , Bone Density/drug effects , Capillaries/pathology , Collagen/analysis , Coloring Agents , Drug Implants , Image Processing, Computer-Assisted/methods , Lymphocytes/pathology , Macrophages/pathology , Osteoblasts/pathology , Osteogenesis/drug effects , Osteotomy/methods , Rabbits , Radiographic Image Enhancement/methods , Thermography/methods , Tibia/blood supply , Tibia/diagnostic imaging , Time Factors , Wound Healing/drug effects
18.
J Biomed Mater Res A ; 101(7): 2038-48, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23255259

ABSTRACT

Scaffolds made of polycaprolactone and nanocrystalline silicon-substituted hydroxyapatite have been fabricated by 3D printing rapid prototyping technique. To asses that the scaffolds fulfill the requirements to be considered for bone grafting applications, they were implanted in New Zealand rabbits. Histological and radiological studies have demonstrated that the scaffolds implanted in bone exhibited an excellent osteointegration without the interposition of fibrous tissue between bone and implants and without immune response after 4 months of implantation. In addition, we have evaluated the possibility of improving the scaffolds efficiency by incorporating demineralized bone matrix during the preparation by 3D printing. When demineralized bone matrix (DBM) is incorporated, the efficacy of the scaffolds is enhanced, as new bone formation occurs not only in the peripheral portions of the scaffolds but also within its pores after 4 months of implantation. This enhanced performance can be explained in terms of the osteoinductive properties of the DBM in the scaffolds, which have been assessed through the new bone tissue formation when the scaffolds are ectopically implanted.


Subject(s)
Bone and Bones/chemistry , Durapatite/chemistry , Polyesters/chemistry , Silicon/chemistry , Tissue Scaffolds/chemistry , Animals , Bone Development/physiology , Bone Substitutes , Bone and Bones/diagnostic imaging , Crystallization , Female , Male , Microscopy, Electron, Scanning , Microtechnology/methods , Nanoparticles , Osteogenesis/drug effects , Prostheses and Implants , Rabbits , Radiography , Spectrophotometry, Ultraviolet , X-Ray Diffraction
19.
J Electrocardiol ; 43(5): 422-4, 2010.
Article in English | MEDLINE | ID: mdl-20392452

ABSTRACT

The knowledge of the heart and its functions is increasing every day. However, many cardiac dysfunctions remain undocumented. One of them might be the presence of the Wellens' sign, minimally elevated or isoelectric ST segments, and inverted T waves in the precordial leads, without changes in the QRS complex, together with a shortened of "P-R and Q-T intervals" in the same electrocardiographic record. Both patterns are greatly underdiagnosed. The key to an accurate diagnosis of both dysfunctions must begin with a detailed analysis of all the symptoms reported by the patient. The ECG recording provides an almost definitive confirmation: The T-wave characteristics in precordial derivations. The duration of P-R and Q-T intervals.


Subject(s)
Acute Coronary Syndrome/diagnosis , Acute Coronary Syndrome/physiopathology , Coronary Stenosis/diagnosis , Coronary Stenosis/physiopathology , Electrocardiography , Acute Coronary Syndrome/surgery , Adult , Biomarkers/analysis , Coronary Angiography , Coronary Stenosis/surgery , Diagnosis, Differential , Humans , Male , Tomography, Emission-Computed, Single-Photon
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