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1.
BJU Int ; 133(1): 53-62, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37548822

RESUMO

OBJECTIVE: To assess the long-term safety of nerve-sparing radical prostatectomy (NSRP) in men with high-risk prostate cancer (PCa) by comparing survival outcomes, disease recurrence, the need for additional therapy, and perioperative outcomes of patients undergoing NSRP to those having non-NSRP. PATIENTS AND METHODS: We included consecutive patients at a single, academic centre who underwent open RP for high-risk PCa, defined as preoperative prostate-specific antigen level of > 20 ng/mL and/or postoperative International Society of Urological Pathology Grade Group 4 or 5 (i.e., Gleason score ≥ 8) and/or ≥pT3 and/or pN1 assessing the RP and lymph node specimen. We calculated a propensity score and used inverse probability of treatment weighting to match baseline characteristics of patients with high-risk PCa who underwent NSRP vs non-NSRP. We analysed oncological outcome as time-to-event and calculated hazard ratios (HRs). RESULTS: A total of 726 patients were included in this analysis of which 84% (n = 609) underwent NSRP. There was no evidence for the positive surgical margin rate being different between the NSRP and non-NSRP groups (47% vs 49%, P = 0.64). Likewise, there was no evidence for the need for postoperative radiotherapy being different in men who underwent NSRP from those who underwent non-NSRP (HR 0.78, 95% confidence interval [CI] 0.53-1.15). NSRP did not impact the risk of any recurrence (HR 0.99, 95% CI 0.73-1.34, P = 0.09) and there was no evidence for survival being different in men who underwent NSRP to those who underwent non-NSRP (HR 0.65, 95% CI 0.39-1.08). There was also no evidence for the cancer-specific survival (HR 0.56, 95% CI 0.29-1.11) or progression-free survival (HR 0.99, 95% CI 0.73-1.34) being different between the groups. CONCLUSION: In patients with high-risk PCa, NSRP can be attempted without compromising long-term oncological outcomes provided a comprehensive assessment of objective (e.g., T Stage) and subjective (e.g., intraoperative appraisal of tissue planes) criteria are conducted.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/patologia , Recidiva Local de Neoplasia/patologia , Prostatectomia/efeitos adversos , Estudos Longitudinais , Gradação de Tumores
2.
Int J Mol Sci ; 24(10)2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37240108

RESUMO

Previously, functional coatings on 3D-printed titanium implants were developed to improve their biointegration by separately incorporating Ga and Ag on the biomaterial surface. Now, a thermochemical treatment modification is proposed to study the effect of their simultaneous incorporation. Different concentrations of AgNO3 and Ga(NO3)3 are evaluated, and the obtained surfaces are completely characterized. Ion release, cytotoxicity, and bioactivity studies complement the characterization. The provided antibacterial effect of the surfaces is analyzed, and cell response is assessed by the study of SaOS-2 cell adhesion, proliferation, and differentiation. The Ti surface doping is confirmed by the formation of Ga-containing Ca titanates and nanoparticles of metallic Ag within the titanate coating. The surfaces generated with all combinations of AgNO3 and Ga(NO3)3 concentrations show bioactivity. The bacterial assay confirms a strong bactericidal impact achieved by the effect of both Ga and Ag present on the surface, especially for Pseudomonas aeruginosa, one of the main pathogens involved in orthopedic implant failures. SaOS-2 cells adhere and proliferate on the Ga/Ag-doped Ti surfaces, and the presence of gallium favors cell differentiation. The dual effect of both metallic agents doping the titanium surface provides bioactivity while protecting the biomaterial from the most frequent pathogens in implantology.


Assuntos
Gálio , Titânio , Titânio/farmacologia , Titânio/química , Prata/farmacologia , Prata/química , Osseointegração , Porosidade , Gálio/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/química , Antibacterianos/farmacologia , Antibacterianos/química , Propriedades de Superfície
3.
ZDM ; 55(1): 35-48, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35891708

RESUMO

The COVID-19 pandemic led to the lockdown of schools in many countries, forcing teachers and students to carry out educational activities remotely. In the case of mathematics, developing remote instruction based on both synchronous and asynchronous technological solutions has proven to be an extremely complex challenge. Specifically, this was the case in topics such as word problem solving, as this domain requires intensive supervision and feedback from the teacher. In this piece of research, we present an evaluation of how technology is employed in the teaching of mathematics, with particular relevance to learning during the pandemic. For that purpose, we conducted a systematic review, revealing the almost complete absence of experiments in which the use of technology is not mediated by the teacher. These results reflect a pessimistic vision within the field of mathematics education about the possibilities of learning when the student uses technology autonomously. Bringing good outcomes out of a bad situation, the pandemic crisis may represent a turning point from which to start directing the research gaze towards technological environments such as those mediated by artificial intelligence. As an example, we provide a study illustrating to what extent intelligent tutoring systems can be cost-effective compared to one-to-one human tutoring and mathematic learning-oriented solutions for intensive supervision in the teaching of word problem solving, especially appropriate for remote settings. Despite the potential of these technologies, the experience also showed that student socioeconomic level was a determining factor in the participation rate with an intelligent tutoring system, regardless of whether or not the administration guaranteed students' access to technological resources during the COVID-19 situation.

4.
Cancers (Basel) ; 16(1)2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38201549

RESUMO

Lymphovascular invasion, whereby tumour cells or cell clusters are identified in the lumen of lymphatic or blood vessels, is thought to be an essential step in disease dissemination. It has been established as an independent negative prognostic indicator in a range of cancers. We therefore aimed to assess the impact of lymphovascular invasion at the time of prostatectomy on oncological outcomes. We performed a multicentre, retrospective cohort study of 3495 men who underwent radical prostatectomy for localised prostate cancer. Only men with negative preoperative staging were included. We assessed the relationship between lymphovascular invasion and adverse pathological features using multivariable logistic regression models. Kaplan-Meier curves and Cox proportional hazard models were created to evaluate the impact of lymphovascular invasion on oncological outcomes. Lymphovascular invasion was identified in 19% (n = 653) of men undergoing prostatectomy. There was an increased incidence of lymphovascular invasion-positive disease in men with high International Society of Urological Pathology (ISUP) grade and non-organ-confined disease (p < 0.01). The presence of lymphovascular invasion significantly increased the likelihood of pathological node-positive disease on multivariable logistic regression analysis (OR 15, 95%CI 9.7-23.6). The presence of lymphovascular invasion at radical prostatectomy significantly increased the risk of biochemical recurrence (HR 2.0, 95%CI 1.6-2.4). Furthermore, lymphovascular invasion significantly increased the risk of metastasis in the whole cohort (HR 2.2, 95%CI 1.6-3.0). The same relationship was seen across D'Amico risk groups. The presence of lymphovascular invasion at the time of radical prostatectomy is associated with aggressive prostate cancer disease features and is an indicator of poor oncological prognosis.

5.
Science ; 378(6621): eabl7207, 2022 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-36395212

RESUMO

Many human cancers manifest the capability to circumvent attack by the adaptive immune system. In this work, we identified a component of immune evasion that involves frequent up-regulation of fragile X mental retardation protein (FMRP) in solid tumors. FMRP represses immune attack, as revealed by cancer cells engineered to lack its expression. FMRP-deficient tumors were infiltrated by activated T cells that impaired tumor growth and enhanced survival in mice. Mechanistically, FMRP's immunosuppression was multifactorial, involving repression of the chemoattractant C-C motif chemokine ligand 7 (CCL7) concomitant with up-regulation of three immunomodulators-interleukin-33 (IL-33), tumor-secreted protein S (PROS1), and extracellular vesicles. Gene signatures associate FMRP's cancer network with poor prognosis and response to therapy in cancer patients. Collectively, FMRP is implicated as a regulator that orchestrates a multifaceted barrier to antitumor immune responses.


Assuntos
Proteína do X Frágil da Deficiência Intelectual , Evasão da Resposta Imune , Tolerância Imunológica , Neoplasias , Animais , Humanos , Camundongos , Proteína do X Frágil da Deficiência Intelectual/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Neoplasias/imunologia , Quimiocina CCL7/metabolismo , Interleucina-33 , Proteína S/metabolismo
6.
World J Orthop ; 13(6): 578-586, 2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35949710

RESUMO

BACKGROUND: Orthopedic implant-related infection remains one of the most serious complications after orthopedic surgery. In recent years, there has been an increased scientific interest to improve prevention and treatment strategies. However, many of these strategies have focused on chemical measures. AIM: To analyze the effect of alternating current electrical fields on bacterial adherence to titanium surfaces. METHODS: Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) were exposed to 6.5 V electrical currents at different frequencies: 0.5 Hz, 0.1 Hz, and 0.05 Hz. After exposure, a bacterial count was then performed and compared to the control model. Other variables registered included the presence of electrocoagulation of the medium, electrode oxidation and/or corrosion, and changes in pH of the medium. RESULTS: The most effective electrical model for reducing S. aureus adhesion was 6.5 V alternating current at 0.05 Hz achieving a 90% adhesion reduction rate. For E. coli, the 0.05 Hz frequency model also showed the most effective results with a 53% adhesion reduction rate, although these were significantly lower than S. aureus. Notable adhesion reduction rates were observed for S. aureus and E.coli in the studied conditions. However, the presence of electrode oxidation makes us presume these conditions are not optimal for in vivo use. CONCLUSION: Although our findings suggest electrical currents may be useful in preventing bacterial adhesion to metal surfaces, further research using other electrical conditions must be examined to consider their use for in vivo trials.

7.
Materials (Basel) ; 13(11)2020 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-32486136

RESUMO

Bone spacers are exclusively used for replacing the tissue after trauma and/or diseases. Ceramic materials bring positive opportunities to enhance greater osteointegration and performance of implants, yet processing of porous geometries can be challenging. Additive Manufacturing (AM) opens opportunities to grade porosity levels in a part; however, its productivity may be low due to its batch processing approach. The paper studies the biological responses yielded by hydroxyapatite with ß-TCP (tricalcium phosphate) ceramic porous bone spacers manufactured by robocasting 2-layer meshes that are rolled in green and sintered. The implants are assessed in vitro and in vivo for their compatibility. Human bone marrow mesenchymal stem cells attached, proliferated and differentiated on the bone spacers produced. Cells on the spacers presented alkaline phosphatase staining, confirming osteogenic differentiation. They also expressed bone-specific COL1A1, BGAP, BSP, and SPP1 genes. The fold change of these genes ranged between 8 to 16 folds compared to controls. When implanted into the subcutaneous tissue of rabbits, they triggered collagen fibre formation and mild fibroblastic proliferation. In conclusion, rolled AM-meshes bone spacers stimulated bone formation in vitro and were biocompatible in vivo. This technology may give the advantage to custom produce spacers at high production rates if industrially upscaled.

8.
J Mater Sci Mater Med ; 27(10): 151, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27582071

RESUMO

Intervertebral implants should be designed with low load requirements, high friction coefficient and low elastic modulus in order to avoid the stress shielding effect on bone. Furthermore, the presence of a highly interconnected porous structure allows stimulating bone in-growth and enhancing implant-bone fixation. The aim of this study was to obtain bioactive porous titanium implants with highly interconnected pores with a total porosity of approximately 57 %. Porous Titanium implants were produced by powder sintering route using the space holder technique with a binder phase and were then evaluated in an in vivo study. The size of the interconnection diameter between the macropores was about 210 µm in order to guarantee bone in-growth through osteblastic cell penetration. Surface roughness and mechanical properties were analyzed. Stiffness was reduced as a result of the powder sintering technique which allowed the formation of a porous network. Compression and fatigue tests exhibited suitable properties in order to guarantee a proper compromise between mechanical properties and pore interconnectivity. Bioactivity treatment effect in novel sintered porous titanium materials was studied by thermo-chemical treatments and were compared with the same material that had undergone different bioactive treatments. Bioactive thermo-chemical treatment was confirmed by the presence of sodium titanates on the surface of the implants as well as inside the porous network. Raman spectroscopy results suggested that the identified titanate structures would enhance in vivo apatite formation by promoting ion exchange for the apatite formation process. In vivo results demonstrated that the bioactive titanium achieved over 75 % tissue colonization compared to the 40 % value for the untreated titanium.


Assuntos
Osteoblastos/metabolismo , Óxidos/química , Titânio/química , Animais , Materiais Biocompatíveis/química , Força Compressiva , Módulo de Elasticidade , Feminino , Fricção , Teste de Materiais , Microscopia Eletrônica de Varredura , Porosidade , Pós , Próteses e Implantes , Desenho de Prótese , Coelhos , Análise Espectral Raman , Estresse Mecânico , Propriedades de Superfície , Temperatura
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