Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 79
Filtrar
1.
Cancers (Basel) ; 16(11)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38893180

RESUMO

(1) Background: to analyze the impact of the COVID-19 pandemic on the characteristics and management of uveal melanoma (UM) in the National Referral Center in Poland. (2) Materials and Methods: the retrospective analysis of 1336 patients who were newly diagnosed with UM at the Department of Ophthalmology and Ophthalmic Oncology, Jagiellonian University Collegium Medicum Krakow, Poland between 1 January 2018 and 31 December 2021. The demographic and clinical data were compiled, including localization, size, and treatment methods of tumors. (3) Results: In total, 728 patients with UM were included before the COVID-19 pandemic, in the years 2018-2019, and 608 were included during the COVID-19 pandemic, in the years 2020-2021. Fixed-base dynamics indicators for the incidence of uveal melanoma (base year 2018) in the National Referral Center in Poland were 80.22% and 86.81% in the years 2020 and 2021, respectively. UMs were statistically significantly larger and more frequently localized anterior to the equator of the eye globe in the year 2021 than in the year 2018 (Chi-square Pearson test p = 0.0001 and p = 0.0077, respectively). The rate of patients treated with enucleation increased from 15.94% in the year 2018 to 26.90% in the year 2021 (Chi-square Pearson test p = 0.0005). (4) Conclusions: Statistically significant differences were found in the management of uveal melanoma in the National Referral Center in Poland during the COVID-19 pandemic with tumors being larger, more frequently localized anterior to the equator of the eye globe, and more often enucleated.

2.
Materials (Basel) ; 17(3)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38591629

RESUMO

While functioning in the oral cavity, denture soft linings (SL) are exposed to contact with the microbiota. Dentures can offer perfect conditions for the multiplication of pathogenic yeast-like fungi, resulting in rapid colonisation of the surface of the materials used. In vitro experiments have also shown that yeast may penetrate SL. This may lead to changes in their initially beneficial functional properties. The aim of this work was to investigate the effect of three months of exposure to a Candida albicans suspension on the mechanical properties of SL material and its bond strength to the denture base polymer, and to additionally verify previous reports of penetration using a different methodology. Specimens of the SL material used were incubated for 30, 60 and 90 days in a suspension of Candida albicans strain (ATCC 10231). Their shore A hardness, tensile strength, and bond strength to acrylic resin were tested. The colonization of the surface and penetration on fractured specimens were analysed with scanning electron and inverted fluorescence microscopes. Exposure to yeast did not affect the mechanical properties. The surfaces of the samples were colonised, especially in crystallized structures of the medium; however, the penetration of hyphae and blastospores into the material was not observed.

3.
Curr Med Chem ; 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38310389

RESUMO

Siderophores are low molecular weight compounds produced by microorganisms to scavenge iron in iron-deficient environments. Rhodotorulic acid, a natural hydroxamate siderophore, plays a vital role in iron acquisition for fungi and bacteria. As the simplest natural hydroxamate siderophore, it exhibits a high affinity for ferric ions, enabling it to form stable complexes that facilitate iron uptake and transport within microorganisms. This article provides a comprehensive analysis of this hydroxamate siderophore, rhodotorulic acid, its synthesis, physicochemical properties, and biological significance. It also explores its applications in antifungal and plant protection strategies. Insights into RA derivatives reveal distinct biological effects and applications with potential in various fields, from antioxidants to antifungals. Rhodotorulic acid and its derivatives show promise for novel therapies, plant protection strategies, and iron supplementation in agriculture. Understanding their properties could advance science and medicine with sustainable practices.

4.
ACS Omega ; 9(1): 1670-1682, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38222608

RESUMO

Surface modification by plasmonic metals is one of the most promising ways to increase the band-to-band excitonic recombination in zinc oxide (ZnO) nanostructures. However, the metal-induced modulation of the UV light emission depends strongly on the production method, making it difficult to recognize the mechanism responsible for charge/energy transfer between the semiconductor and a metal. Therefore, in this study, the ZnO/Ag and Au hybrids were produced by the same, fully controlled experimental approach. ZnO nanotubes (NTs), fabricated by a template-assisted ALD synthesis, were coated by metals of variable mass thickness (1-6.5 nm thick) using the electron beam PVD technique. The deposited Ag and Au metals grew in the form of island films made of metallic nanoparticles (NPs). The size of the NPs and their size distribution decreased, while the spacing between the NPs increased as the mass of the deposited Ag and Au metals decreased. Systematic optical analysis allowed us to unravel a specific role of surface defects in ZnO NTs in the processes occurring at the ZnO/metal interface. The enhancement of the UV emission was observed only in the ZnO/Ag system. The phenomena were tentatively ascribed to the coupling between the defect-related (DL) excitonic recombination in ZnO and the localized surface plasmon resonance (LSPR) at the Ag NPs. However, the enhancement of UV light was observed only for a narrow range of Ag NP dimensions, indicating the great importance of the size and internanoparticle spacing in the plasmonic coupling. Moreover, the enhancement factors were much stronger in ZnO NTs characterized by robust DL-related emission before metal deposition. In contrast to Ag, Au coatings caused quenching of the UV emission from ZnO NTs, which was attributed to the uncoupling between the DL and LSP energies in this system and a possible formation of the ohmic contact between the Au metal and the ZnO.

5.
Sci Rep ; 13(1): 9882, 2023 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-37337014

RESUMO

Even though running performance and positional profiles in football are well described, amputee football (AF) has different characteristics of the movement, pitch dimensions, and time played. There is a gap in the scientific literature about positional profiles based on running performance in AF. This study aimed to investigate the differences between positions, the influence of the amputation level or defect of the lower limb (LD), the differences in running performance between halves, and the relationship with the final match result. Thirteen AF National Team players were monitored by Global Navigation Satellite System (GNSS), tracking 24 official international matches for 17 months. Values of top speed, peak acceleration, peak deceleration, average distance per minute, sprint mean speed, GPS load per minute, inertial load per minute (Gs load/min), number of sprints per minute, and a number of impacts per minute were analyzed for defenders (DEF), midfielders (MID) and forwards (FOR). Additional factors analyzed were amputation level (below the knee, low amputation-LA or over the knee, high amputation-HA or defect of the lower limb-LD) and the match's final result. Midfielders had significantly higher running performance parameters compared to other positions (greater top speed than DEF (+ 0.3 m/s; p < 0.001) and FOR (+ 0.2 m/s; p = 0.045), greater peak acceleration and deceleration than DEF (+ 0.5 m/s2 for both measures; p < 0.001) and FOR (+ 0.4 and + 0.3 m/s2; p < 0.001 and p = 0.036, respectively), greater GPS load/minute than DEF (+ 0.2 load/min; p = 0.001) and FOR (+ 0.3 load/min; p < 0.001), greater Gs load per minute than DEF (+ 2.7 load/min; p < 0.001) and FOR (+ 1.8 load/min; p < 0.001), greater number of impacts per minute than DEF (+ 0.2 n/min; p < 0.001) and FOR (+ 0.2 n/min; p < 0.001). Players with LD had significantly higher running performance than those with LA or HA. In the match's second half, a decrease in running performance was registered. The trend of running more when losing could be observed-AF players had higher running parameters in lost matches, but the differences were not statistically significant. Further research complied with contextual game analysis is needed to assess the running performance of AF players deeply.


Assuntos
Amputados , Desempenho Atlético , Futebol Americano , Humanos , Aceleração , Sistemas de Informação Geográfica
6.
Sci Rep ; 13(1): 7579, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37165035

RESUMO

Tumor recurrence affects up to 70% of early-stage hepatocellular carcinoma (HCC) patients, depending on treatment option. Deep learning algorithms allow in-depth exploration of imaging data to discover imaging features that may be predictive of recurrence. This study explored the use of convolutional neural networks (CNN) to predict HCC recurrence in patients with early-stage HCC from pre-treatment magnetic resonance (MR) images. This retrospective study included 120 patients with early-stage HCC. Pre-treatment MR images were fed into a machine learning pipeline (VGG16 and XGBoost) to predict recurrence within six different time frames (range 1-6 years). Model performance was evaluated with the area under the receiver operating characteristic curves (AUC-ROC). After prediction, the model's clinical relevance was evaluated using Kaplan-Meier analysis with recurrence-free survival (RFS) as the endpoint. Of 120 patients, 44 had disease recurrence after therapy. Six different models performed with AUC values between 0.71 to 0.85. In Kaplan-Meier analysis, five of six models obtained statistical significance when predicting RFS (log-rank p < 0.05). Our proof-of-concept study indicates that deep learning algorithms can be utilized to predict early-stage HCC recurrence. Successful identification of high-risk recurrence candidates may help optimize follow-up imaging and improve long-term outcomes post-treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Recidiva Local de Neoplasia/diagnóstico por imagem , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Aprendizado de Máquina
7.
Rom J Ophthalmol ; 67(1): 33-40, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37089804

RESUMO

Objective: Low levels of outdoor activity are known to be an important risk factor for the development of myopia in schoolchildren. This study aimed to determine outdoor and near work patterns in Polish schoolchildren before and during school closure due to the SARS-CoV-2 pandemic. Methods: All children undergoing a routine pediatric examination in the Elblag branch of the Hygeia Clinic, together with their parents, were asked to fill an anonymous questionnaire. The subject's age, spherical equivalent (SE) refractive error, time spent outdoors, screen time and total near work in hours per day before and during the pandemic, were recorded. As substantial differences in physical activity by time of year were reported, activity patterns for June (summer) and December (winter) were recorded. Multiple logistic regression analysis was used to analyze the association between the presence of myopia and outdoor and total near work time at different timepoints. Results: A total of 61 schoolchildren aged 11.95 ± 2.74 (range 7 to 17) years were included in this study. The mean SE in the right eye was -1.78 ± 2.11 with 46% of the individuals (n=28) classified as myopic. Before the pandemic, higher time outdoors was associated with less myopic SE (OR=0.47, 95% Confidence Interval [CI] 0.24 to 0.93). During the pandemic, time outdoors among non-myopic children was similar to myopic children, both during winter and summer months (2.18 ± 1.81 vs. 1.89 ± 1.50; P=.51, and 3.47 ± 2.66 vs. 3.31 ± 1.65; P=.79 respectively). Time outdoors was not significantly associated with myopia during the pandemic (OR=1.17, 95% CI 0.64 to 2.14). Total near work was not associated with myopia at any time point. Conclusion: The long-term influence of the changing patterns of outdoor and near work on myopia prevalence and progression in our population is still to be established. Nevertheless, it is likely that the decrease of outdoor time may influence the rates of myopia in this region.


Assuntos
COVID-19 , Miopia , Humanos , Criança , SARS-CoV-2 , Pandemias , Atividades de Lazer , COVID-19/epidemiologia , Inquéritos e Questionários , Miopia/epidemiologia
8.
Eur J Med Chem ; 252: 115293, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36958265

RESUMO

Conjugates composed of C2-18 fatty acid (FA) residues as a molecular carrier and 5-fluorocytosine (5-FC) as an active agent, released upon the action of intracellular esterases on the ester bond between FA and "trimethyl lock" intramolecular linker, demonstrate good in vitro activity against human pathogenic yeasts of Candida spp. The minimal inhibitory concentrations (MIC) values for the most active conjugates containing caprylic (C8), capric (C10), lauric (C12), or myristic (C14) acid residues were in the 2-64 µg mL-1 range, except for these against the least susceptible Candida krusei. The least active conjugates containing C2, C16, or C18 FA were slowly hydrolyzed by esterase and probably poorly taken up by Candida cells, as found for their analogs containing a fluorescent label, Nap-NH2 instead of 5-FC.


Assuntos
Antifúngicos , Ácidos Graxos , Humanos , Ácidos Graxos/farmacologia , Ácidos Graxos/química , Antifúngicos/farmacologia , Candida , Leveduras
9.
J Clin Med ; 12(4)2023 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-36835996

RESUMO

AIMS: The present study aimed to analyze the incidence and characteristics of all types of retinal detachment (RD) in the overall population of Polish adults during 2013-2019. METHODS: Data from all levels of healthcare services at public and private institutions recorded in the National Health Fund (NHF) database were evaluated. International Classification of Diseases codes (ICD-9 and ICD-10) and unique NHF codes were used to identify RD patients and RD treatment procedures. RESULTS: In the period 2013-2019, 71,073 patients with RD were newly diagnosed in Poland. The average incidence was 32.64/100,000 person-years (95% CI: 31.28-33.99) and it increased with the age of patients, with the highest rate in the group of patients ≥70 years of age. The overall incidences of rhegmatogenous RD, traction RD, serous RD, other RD and unspecified RD were 13.72/100,000, 2.03/100,000, 1.02/100,000, 7.90/100,000 and 7.97/100,000 person-years, respectively. The most common surgical treatment for RD in Poland was PPV performed on average in 49.80% of RD patients. The risk factor analyses showed that rhegmatogenous RD was significantly associated with age (OR 1.026), male sex (OR 2.320), rural residence (OR 0.958), DM type 2 (OR 1.603), any DR (OR 2.109), myopia (OR 2.997), glaucoma (OR 2.169) and uveitis (OR 2.561). Traction RD was also significantly associated with age (OR 1.013) and male sex (OR 2.785) as well as with any DR (OR 2.493), myopia (OR 2.255), glaucoma (OR 1.904) and uveitis (OR 4.214). Serous RD was significantly associated with all analyzed risk factors except DM type 2. CONCLUSIONS: The total incidence of retinal detachment in Poland was higher than found in previously published studies. Our study demonstrated that diabetes type 1 and diabetic retinopathy are risk factors of development of serous RD, which is presumably associated with the disruption of the blood-retinal barriers in these conditions.

10.
J Pers Med ; 13(2)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36836586

RESUMO

(1) Background: The aim of this study was to analyze the sex differences in the treatment of uveal melanoma (UM) in a group of 1336 patients from a national referral center during the period 2018-2021. (2) Materials and Methods: The study was designed in a retrospective manner. A total of 1336 patients who were newly diagnosed with UM at the Department of Ophthalmology and Ophthalmic Oncology, Jagiellonian University Collegium Medicum, Krakow, Poland, between 1 January 2018 and 31 December 2021, were included in the study. The demographic and clinical data were compiled, including the sex of patients and the treatment methods. (3) Results: In total, 1336 patients with ocular melanoma were identified, including 726 women (54.34%) and 610 men (45.66%). A total of 49.70% of tumors were localized in the right eye and 50.30% in the left eye. UMs were localized statistically significantly more frequently posterior to the equator of the eye globe in men than in women (79.67% vs. 74.10%, Chi^2 Pearson test p = 0.035). Tumors tended to be larger in men, but this difference was not clinically significant. Men were enucleated more often than women (23.44% vs. 18.04%, Chi^2 Pearson test p = 0.015). (4) Conclusions: Statistically significant sex differences were found in the treatment of uveal melanoma in a national referral center in Poland, with men being enucleated more often than women.

11.
AJR Am J Roentgenol ; 220(2): 245-255, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35975886

RESUMO

BACKGROUND. Posttreatment recurrence is an unpredictable complication after liver transplant for hepatocellular carcinoma (HCC) that is associated with poor survival. Biomarkers are needed to estimate recurrence risk before organ allocation. OBJECTIVE. This proof-of-concept study evaluated the use of machine learning (ML) to predict recurrence from pretreatment laboratory, clinical, and MRI data in patients with early-stage HCC initially eligible for liver transplant. METHODS. This retrospective study included 120 patients (88 men, 32 women; median age, 60.0 years) with early-stage HCC diagnosed who were initially eligible for liver transplant and underwent treatment by transplant, resection, or thermal ablation between June 2005 and March 2018. Patients underwent pretreatment MRI and posttreatment imaging surveillance. Imaging features were extracted from postcontrast phases of pretreatment MRI examinations using a pretrained convolutional neural network. Pretreatment clinical characteristics (including laboratory data) and extracted imaging features were integrated to develop three ML models (clinical model, imaging model, combined model) for predicting recurrence within six time frames ranging from 1 through 6 years after treatment. Kaplan-Meier analysis with time to recurrence as the endpoint was used to assess the clinical relevance of model predictions. RESULTS. Tumor recurred in 44 of 120 (36.7%) patients during follow-up. The three models predicted recurrence with AUCs across the six time frames of 0.60-0.78 (clinical model), 0.71-0.85 (imaging model), and 0.62-0.86 (combined model). The mean AUC was higher for the imaging model than the clinical model (0.76 vs 0.68, respectively; p = .03), but the mean AUC was not significantly different between the clinical and combined models or between the imaging and combined models (p > .05). Kaplan-Meier curves were significantly different between patients predicted to be at low risk and those predicted to be at high risk by all three models for the 2-, 3-, 4-, 5-, and 6-year time frames (p < .05). CONCLUSION. The findings suggest that ML-based models can predict recurrence before therapy allocation in patients with early-stage HCC initially eligible for liver transplant. Adding MRI data as model input improved predictive performance over clinical parameters alone. The combined model did not surpass the imaging model's performance. CLINICAL IMPACT. ML-based models applied to currently underutilized imaging features may help design more reliable criteria for organ allocation and liver transplant eligibility.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Estudos Retrospectivos , Fatores de Risco , Imageamento por Ressonância Magnética/métodos , Recidiva Local de Neoplasia/epidemiologia
13.
Nano Lett ; 22(21): 8601-8607, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36279222

RESUMO

Tunneling spectroscopy measurements are often used to probe the energy spectrum of Andreev bound states (ABSs) in semiconductor-superconductor hybrids. Recently, this spectroscopy technique has been incorporated into planar Josephson junctions (JJs) formed in two-dimensional electron gases, a potential platform to engineer phase-controlled topological superconductivity. Here, we perform ABS spectroscopy at the two ends of planar JJs and study the effects of the magnetic vector potential on the ABS spectrum. We show that the local superconducting phase difference arising from the vector potential is equal in magnitude and opposite in sign at the two ends, in agreement with a model that assumes localized ABSs near the tunnel barriers. Complemented with microscopic simulations, our experiments demonstrate that the local phase difference can be used to estimate the relative position of localized ABSs separated by a few hundred nanometers.

14.
Int J Mol Sci ; 23(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36142160

RESUMO

In recent years, zebrafish (ZF) has been increasingly applied as a model in human disease studies, with a particular focus on cancer. A number of advantages make it an attractive alternative for mice widely used so far. Due to the many advantages of zebrafish, modifications can be based on different mechanisms and the induction of human disease can take different forms depending on the research goal. Genetic manipulation, tumor transplantation, or injection of the pathogen are only a few examples of using ZF as a model. Most of the studies are conducted in order to understand the disease mechanism, monitor disease progression, test new or alternative therapies, and select the best treatment. The transplantation of cancer cells derived from patients enables the development of personalized medicine. To better mimic a patient's body environment, immune-deficient models (SCID) have been developed. A lower immune response is mostly generated by genetic manipulation but also by irradiation or dexamethasone treatment. For many studies, using SCID provides a better chance to avoid cancer cell rejection. In this review, we describe the main directions of using ZF in research, explain why and how zebrafish can be used as a model, what kind of limitations will be met and how to overcome them. We collected recent achievements in this field, indicating promising perspectives for the future.


Assuntos
Neoplasias , Peixe-Zebra , Animais , Dexametasona , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos SCID , Neoplasias/genética , Peixe-Zebra/genética
15.
Front Plant Sci ; 13: 926305, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35982694

RESUMO

Plant tissue culture techniques are handy tools for obtaining unique plant materials that are difficult to propagate or important for agriculture. Homozygous materials derived through in vitro cultures are invaluable and significantly accelerate the evaluation of new varieties, e.g., cereals. The induction of somatic embryogenesis/androgenesis and the regeneration and its efficiency can be influenced by the external conditions of tissue culture, such as the ingredients present in the induction or regeneration media. We have developed an approach based on biological system, molecular markers, Fourier Transform Infrared spectroscopy, and structural equation modeling technique to establish links between changes in sequence and DNA methylation at specific symmetric (CG, CHG) and asymmetric (CHH) sequences, glutathione, and green plant regeneration efficiency in the presence of variable supplementation of induction medium with copper ions. The methylation-sensitive Amplified Fragment Length Polymorphism was used to assess tissue culture-induced variation, Fourier Transform Infrared spectroscopy to describe the glutathione spectrum, and a structural equation model to develop the relationship between sequence variation, de novo DNA methylation within asymmetric sequence contexts, and copper ions in the induction medium, as well as, glutathione, and green plant efficiency. An essential aspect of the study is demonstrating the contribution of glutathione to green plant regeneration efficiency and indicating the critical role of copper ions in influencing tissue culture-induced variation, glutathione, and obtaining green regenerants. The model presented here also has practical implications, showing that manipulating the concentration of copper ions in the induction medium may influence cell function and increases green plant regeneration efficiency.

16.
J Enzyme Inhib Med Chem ; 37(1): 1928-1956, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35801410

RESUMO

Glucosamine-6-phosphate synthase (GlcN-6-P synthase) is known as a promising target for antimicrobial agents and antidiabetics. Several compounds of natural or synthetic origin have been identified as inhibitors of this enzyme. This set comprises highly selective l-glutamine, amino sugar phosphate or transition state intermediate cis-enolamine analogues. Relatively low antimicrobial activity of these inhibitors, poorly penetrating microbial cell membranes, has been improved using the pro-drug approach. On the other hand, a number of heterocyclic and polycyclic compounds demonstrating antimicrobial activity have been presented as putative inhibitors of the enzyme, based on the results of molecular docking to GlcN-6-P synthase matrix. The most active compounds of this group could be considered promising leads for development of novel antimicrobial drugs or antidiabetics, provided their selective toxicity is confirmed.


Assuntos
Anti-Infecciosos , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante) , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/metabolismo , Hipoglicemiantes , Simulação de Acoplamento Molecular
17.
Materials (Basel) ; 15(11)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35683140

RESUMO

Yeast-like fungi such as Candida albicans (C. albicans) are the primary pathogenic microorganism in the oral cavity of denture wearers. The research available so far, conducted according to a protocol based on the exposure of specimens to a C. albicans suspension and their cutting with water cooling, shows that hard polymethyl methacrylate (PMMA) prosthetic materials are not only surface colonized, but also penetrated by microorganisms in a short time. This justifies the hypothesis that exposure to a suspension of the C. albicans strain causes the changes in mechanical properties due to surface colonization and/or penetration of the samples. In the current study, the chosen mechanical properties (flexural strength, flexural modulus, tensile strength, impact strength, ball indentation hardness, and surface Vickers hardness at 300 g load) of the PMMA denture base material Vertex RS (Vertex-Dental, The Netherlands) exposed for 30, 60, and 90 days to a suspension of C. albicans were investigated. The potential penetration of yeast was examined on the fractured surfaces (interior of specimens) to eliminate the risk of the contamination of samples during cutting. There was no influence on the flexural strength, flexural modulus, tensile strength, impact strength, or ball indentation hardness, but a significant decrease in surface hardness was registered. Microscopic observations did not confirm the penetration of C. albicans. On the surface, blastospores and pseudohyphae were observed in crystallized structures and in traces after grinding, which indicates that in clinical conditions, it is not penetration but the deterioration of surface quality, which may lead to the formation of microareas that are difficult to disinfect, causing rapid recolonization.

18.
Molecules ; 27(11)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35684391

RESUMO

Hydroxyl radical (•OH) scavenging and the regeneration of Fe2+ may inhibit or enhance peroxidative damage induced by a Fenton system, respectively. Plant polyphenols reveal the afore-mentioned activities, and their cumulative net effect may determine anti- or pro-oxidant actions. We investigated the influence of 17 phenolics on ultra-weak photon emission (UPE) from a modified Fenton system (92.6 µmol/L Fe2+, 185.2 µmol/L EGTA (ethylene glycol-bis(ß-aminoethyl-ether)-N,N,N',N,-tetraacetic acid) and 2.6 mmol/L H2O2 pH = 7.4). A total of 8 compounds inhibited (antioxidant effect), and 5 enhanced (pro-oxidant effect) UPE at all studied concentrations (5 to 50 µmol/L). A total of 4 compounds altered their activity from pro- to antioxidant (or vice versa) along with increasing concentrations. A total of 3 the most active of those (ferulic acid, chlorogenic acid and cyanidin 3-O-glucoside; mean UPE enhancement by 63%, 5% and 445% at 5 µmol/L; mean UPE inhibition by 28%, 94% and 24% at 50 µmol/L, respectively) contained catechol or methoxyphenol structures that are associated with effective •OH scavenging and Fe2+ regeneration. Most likely, these structures can determine the bidirectional, concentration-dependent activity of some phenolics under stable in vitro conditions. This is because the concentrations of the studied compounds are close to those occurring in human fluids, and this phenomenon should be considered in the case of dietary supplementation with isolated phenolics.


Assuntos
Peróxido de Hidrogênio , Polifenóis , Antioxidantes/química , Antioxidantes/farmacologia , Ácido Egtázico , Humanos , Peróxido de Hidrogênio/química , Fenóis/química , Fenóis/farmacologia , Polifenóis/farmacologia , Espécies Reativas de Oxigênio
19.
Materials (Basel) ; 15(9)2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35591623

RESUMO

Adhesive joints are widely used in the construction of machines and motor vehicles. Manufacturers replace them with the welding and spot-welding methods due to the lack of damage to the material structure in the joint area. Moreover, it is aimed at reducing the weight of vehicles and producing elements with complex shapes. Therefore, additive manufacturing technology has been increasingly used in the production stage. This fact has not only changed the view on the possibilities of further development of the production technology itself, but it has also caused an intense interest among a greater number of companies in the advantages of structural optimization. There is a natural relationship between these two areas in the design and production, allowing for almost unlimited possibilities of designing new products. The main goal of the research described in this article was to determine the correlation between the strength of the adhesive joint of elements produced using additive technology and the parameters of the ultrasonic wave propagating in the area of the adhesive bond. The tests were carried out on samples made of AlSiMg0.6 material and a structural adhesive. Strength tests were performed to determine the shear force which damaged the joint. Furthermore, an ultrasonic echo technique enabling the determination of a nondestructive measure of the quality and strength of the joint was developed. The samples of the adhesive joints had a strength of about 18.75-28.95 MPa, which corresponded to an ultrasonic measure range of 4.6-7.8 dB. The determined regression relationship had a coefficient of determination at the level of 0.94. Additional ultrasonic tests of materials made with the additive technology confirmed its different acoustic properties in relation to aluminum produced with the standard casting or extrusion process. Designated dependence combining the mechanical strength and the decibel difference between the first and second impulses from the bottom of the joint may constitute the basis for the development of a nondestructive technique for testing the strength of adhesive joints.

20.
Adv Clin Exp Med ; 31(6): 615-621, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35349230

RESUMO

BACKGROUND: Oncology trends are based on data coming from different countries and ocular melanoma is the most common primary eye cancer in adults. OBJECTIVES: To investigate the incidence and characteristics of ocular melanoma in the overall population of Poland. MATERIAL AND METHODS: The retrospective survey of both the National Cancer Registry (NCR) and National Health Fund (NHF) databases was performed to identify all ocular melanoma cases in Poland in 2010-2017. RESULTS: The mean incidence of ocular melanoma was 8.76/1,000,000 person-years; the lowest incidence was observed in the 19-29 age group (1.17/1,000,000 person-years) and the highest in the group over 70 (22.88/1,000,000 person-years). There were no statistically significant trends in the incidence rates over the study period. The overall incidences of uveal, eyelid and conjunctival melanoma were 6.67/1,000,000, 0.47/1,000,000 and 0.28/1,000,000 person-years, respectively. The 5-year overall survival (OS) was 60.76%; the higher risk of death was associated with male sex (hazard ratio (HR) = 1.2959), older age at diagnosis (HR = 1.0379), chemotherapy treatment (HR = 1.6774), metastasis (HR = 1.5716), loco-regional hyperplasia (HR = 1.5936), and systemic tumor spread (HR = 3.9872), compared to the carcinoma in situ. The risk of death was reduced by radiotherapy treatment (HR = 0.6645). CONCLUSIONS: The incidence rate of ocular melanoma in Poland is in the middle of the range worldwide, and the 5-year OS is relatively low.


Assuntos
Neoplasias Oculares , Melanoma , Adulto , Neoplasias Oculares/epidemiologia , Neoplasias Oculares/terapia , Humanos , Incidência , Masculino , Melanoma/epidemiologia , Melanoma/patologia , Melanoma/terapia , Polônia/epidemiologia , Sistema de Registros , Estudos Retrospectivos , Taxa de Sobrevida
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...