Pathophysiology of ovarian cancer prevention

Trabalho Final do Mestrado Integrado em Medicina apresentado à Faculdade de MedicinaO cancro do ovário apresenta uma elevada taxa de mortalidade. Assim, é importante compreender como se desenvolve esta neoplasia para que se possam adoptar estratégias preventivas de forma a diminuir a incidência da mesma e, consequentemente, a sua mortalidade. Nos dias de hoje, os autores são unânimes em considerar que, nos últimos anos tem havido uma mudança quanto à fisiopatologia do cancro do ovário. Atualmente, os tumores do ovário são divididos em Tipo I e Tipo II. Os de tipo I são menos comuns, apresentam-se em estádios menos avançados e, normalmente, têm origem numa lesão percursora. Os de tipo II estão associados a estádios mais avançados e são responsáveis pela maior parte das mortes. Pensa-se agora que a maior parte dos tumores tipo II se desenvolvem devido à progressão neoplásica de células epiteliais da trompa de Falópio. É também consensual que as portadoras de mutações nos genes BRCA 1 e 2 têm um risco acrescido de virem a desenvolver cancro do ovário, pelo que se torna imperativo identificar estas mulheres para que se possam adoptar medidas preventivas. Sendo assim, estas mulheres devem ser aconselhadas a realizar salpingooforectomia bilateral entre os 35 e os 40 anos. A salpingectomia bilateral é também um protocolo cirúrgico com eficácia comprovada e deve ser oferecida e discutida com mulheres de baixo-risco aquando da realização de cirurgia ginecológica por outros motivos ou como método contraceptivo definitivo, em detrimento da laqueação tubária. No entanto, há mulheres que não se sentem preparadas para se submeterem a estas intervenções cirúrgicas, tornando-se importante disponibilizar-lhes medidas de prevenção médica. O uso de contraceptivos orais reduz o risco de desenvolvimento de alguns subtipos histológicos de carcinoma do ovário, nomeadamente o seroso, pelo que deve ser aconselhado como método contraceptivo.Ovarian cancer has a high mortality rate. Thus, it is important to determine how this neoplasia develops so that preventive strategies can be adopted in order to reduce its incidence and, consequently, its mortality.Nowadays, the authors are unanimous to consider that in recent years there has been a shift regarding the pathophysiology of ovarian cancer. Currently, ovarian tumors are divided into Type I and Type II. Type I are less common, are presented in less advanced stages, and usually originate from a precursor lesion. Type II are associated with more advanced stages and are responsible for most of the deaths. It is now thought that most type II tumors develop due to neoplastic transformation of fallopian tube epithelial cells.It is also consensual that carriers of mutations in the BRCA 1 and 2 genes have an increased risk of developing ovarian cancer, so it is imperative to identify this women so they can take preventive measures. Therefore, these women should be advised to perform bilateral salpingo-oophorectomy between the ages of 35 and 40. Bilateral salpingectomy is also a surgical protocol with proven efficacy and should be offered and discussed with low-risk women when performing gynecological surgery for other reasons or as a definitive contraceptive method, in detriment to tubal ligation. However, there are women who do not feel prepared to undergo these surgical interventions, making it important to provide them with medical prevention measures. The use of oral contraceptives reduces the risk of development of some histological subtypes of ovarian carcinoma, namely serous carcinoma and should therefore be counseled as a contraceptive method

Multicentric Study to Assess Helicobacter pylori Incidence, Patient Reported Adverse Events, Compliance and Effectiveness, in Real-World Setting

Helicobacter pylori ( H. pylori) plays an important role in chronic gastritis and globally it is estimated to be present in half of the world’s population. In Portugal, prevalence reaches 85% and its eradication is recommended using quadruple antibiotic therapy, with or without bismuth. We intended to characterize the prescribed treatments evaluating effectiveness, adverse outcomes and compliance in a real-world setting in a primary care unit. A prospective multicenter observational cohort study was developed in five primary care units of Braga, Portugal. Patients diagnosed with H. pylori infection from August 2021 to January 2022 were included. Data were collected by interview (3 weeks after treatment) and review of medical records. Comparison between two groups of treatment and multivariable analysis was conducted. We estimated 13.4 cases per 1000 adults/year from 185 diagnoses. Therapy with bismuth was the most prescribed (83.8%) with a 96.7% eradication rate. There were no significant differences between treatments. Adverse events were reported in 73.8% of inquiries and female patients were associated with higher reports of nausea (p = 0.03) and metallic taste (p = 0.02). Both eradication schemes were effective and secure. The higher rate of adverse outcomes should be validated but it could influence the debate concerning treating all patients, especially in low gastric cancer-prevalence regions

Influence of ns-Nd:YAG laser surface treatment on the tensile bond strength of zirconia to resin-matrix cements

The main aim of this study was to assess the effect of ns-Nd:YAG laser structuring over zirconia green compacts on the adhesion of sintered zirconia to resin-matrix cements. Zirconia (3Y-TZP) compacts were divided according to the type of surface modification: GB – alumina grit-blasted sintered specimens; G8L – laser structured zirconia green compacts (square pattern 8 lines); G16L - laser structured zirconia green compacts (square pattern 16 lines); G8L/GB – alumina grit-blasted G8L specimens after sintering. Specimens of same group were cleaned, cemented using a dual cure resin-matrix cement and aged in distilled water for 24 h (37 °C). Afterwards, the tensile bond strength was measured using a universal test machine. Specimens were analyzed by field emission guns scanning electron microscopy (FEGSEM) and white light interferometry (WLI). Laser-structured surfaces showed higher roughness values and improved morphological aspects for adhesion to resin-matrix cements. Higher tensile bond strength mean values of zirconia to resin-matrix cements were recorded for G8L (16.7 ± 3.8 MPa) and G16L (13.6 ± 3.0 MPa) groups when compared to those recorded for ordinary grit-blasted zirconia surfaces to resin-matrix cements (10 ± 3.1 MPa). The highest tensile bond strength results were recorded for the G8L/GB group (24.2 ± 7.6 MPa). The laser texturing of green zirconia surfaces promoted an increase in roughness and changes in morphological aspects of sintered zirconia for improved adhesion to resin-matrix cements

Multiscale modelling of the thermoelastic properties of alumina-zirconia ceramics for 3D printing

Additive manufacturing appears to facilitate the accurate manufacturing of alumina-zirconia technical ceramics. Nevertheless, the fine tuning of the manufacturing of these components by 3D printing requires an analysis of the parameters that influence their final thermoelastic properties. In this context, this work presents the application of (finite element-based) numerical procedures that aim at the prediction of the effective thermoelastic properties of 3D-printed alumina-zirconia ceramics. The numerical modelling considers three different scales: micro-, meso- and macroscale. The microscale corresponds to the microstructural level of, sintered at 1500 ºC, slip-casted samples with different compositions of alumina-zirconia. On the other hand, the macroscale corresponds to the macrostructural level of porous lattice of 3D-printed ceramics, being defined at the mesoscale level by a periodic unit cell. Thus, an initial microstructural analysis (at microscale level) provides the influence of the alumina/zirconia ratio on the (macroscopically homogeneous and isotropic) material thermoelastic properties, which together with the definition of the geometry of a periodic unit cell (at mesoscale level), provides, by a second analysis (at both the meso- and macroscale levels), the coupled influence of material and geometry of the macrostructural lattice on the structural (macroscopically heterogeneous and anisotropic) thermoelastic properties. Moreover, experimental thermoelastic properties of the sintered slip-casted specimens were obtained for several alumina/zirconia ratios and analyzed together with microstructure patterns. Prediction of the microstructural effective thermoelastic properties was also made using micromechanics and composite theory (analytical) models. All the numerical, experimental and analytical results for the microstructural level are presented and compared. Numerical results for the meso- and macrostructural levels are also presented.publishe