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1.
Int J Mol Sci ; 25(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38791187

RESUMO

Non-coding RNAs (ncRNAs) represent a broad family of molecules that regulate gene expression, including microRNAs, long non-coding RNAs and circular RNAs, amongst others. Dysregulated expression of ncRNAs alters gene expression, which is implicated in the pathogenesis of several malignancies and inflammatory diseases. Gastric cancer is the fifth most frequently diagnosed cancer and the fourth most common cause of cancer-related death. Studies have found that altered expression of ncRNAs may contribute to tumourigenesis through regulating proliferation, apoptosis, drug resistance and metastasis. This review describes the potential use of ncRNAs as diagnostic and prognostic biomarkers. Moreover, we discuss the involvement of ncRNAs in the pathogenesis of gastric cancer, including their interactions with the members of major signalling pathways.


Assuntos
Biomarcadores Tumorais , Regulação Neoplásica da Expressão Gênica , RNA não Traduzido , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Neoplasias Gástricas/etiologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Prognóstico , Transdução de Sinais , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Circular/metabolismo
2.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38612637

RESUMO

Psoriasis is a chronic inflammatory skin disease, the prevalence of which is increasing. Genetic, genomic, and epigenetic changes play a significant role in the pathogenesis of psoriasis. This review summarizes the impact of epigenetics on the development of psoriasis and highlights challenges for the future. The development of epigenetics provides a basis for the search for genetic markers associated with the major histocompatibility complex. Genome-wide association studies have made it possible to link psoriasis to genes and therefore to epigenetics. The acquired knowledge may in the future serve as a solid foundation for developing newer, increasingly effective methods of treating psoriasis. In this narrative review, we discuss the role of epigenetic factors in the pathogenesis of psoriasis.


Assuntos
Estudo de Associação Genômica Ampla , Psoríase , Humanos , Psoríase/genética , Epigenômica , Pele , Epigênese Genética
3.
Int J Mol Sci ; 25(7)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38612710

RESUMO

Cardiovascular diseases (CVDs) are the leading cause of death and include several vascular and cardiac disorders, such as atherosclerosis, coronary artery disease, cardiomyopathies, and heart failure. Multiple treatment strategies exist for CVDs, but there is a need for regenerative treatment of damaged heart. Stem cells are a broad variety of cells with a great differentiation potential that have regenerative and immunomodulatory properties. Multiple studies have evaluated the efficacy of stem cells in CVDs, such as mesenchymal stem cells and induced pluripotent stem cell-derived cardiomyocytes. These studies have demonstrated that stem cells can improve the left ventricle ejection fraction, reduce fibrosis, and decrease infarct size. Other studies have investigated potential methods to improve the survival, engraftment, and functionality of stem cells in the treatment of CVDs. The aim of the present review is to summarize the current evidence on the role of stem cells in the treatment of CVDs, and how to improve their efficacy.


Assuntos
Doenças Cardiovasculares , Doença da Artéria Coronariana , Cardiopatias , Células-Tronco Pluripotentes Induzidas , Humanos , Doenças Cardiovasculares/terapia , Miócitos Cardíacos
4.
Int J Mol Sci ; 25(8)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38674053

RESUMO

Using different three-drug immunosuppressive treatment regimens in a rat model, we aimed to determine the effects of long-term therapy on metalloproteinase-2 and metalloproteinase-9 activity and the expression of their inhibitors, as well as to assess the morphology of the animals' cardiac tissue. Our results suggest that chronic use of immunosuppressive drugs disrupts the balance between the activity of MMPs and TIMPs. Depending on the type of drug regimen used, this leads to abnormalities in the cardiac structure, collagen fiber accumulation, or cardiomyocyte hypertrophy. The information obtained in the present study allows us to conclude that the chronic treatment of rats with the most common clinical immunosuppressive regimens may contribute to abnormalities in the myocardial structure and function. The results presented in this study may serve as a prelude to more in-depth analyses and additional research into the optimal selection of an immunosuppressive treatment with the lowest possible risk of cardiovascular complications for patients receiving organ transplants.


Assuntos
Imunossupressores , Metaloproteinase 2 da Matriz , Metaloproteinase 9 da Matriz , Miocárdio , Animais , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/genética , Imunossupressores/farmacologia , Metaloproteinase 9 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Ratos , Miocárdio/patologia , Miocárdio/metabolismo , Masculino , Ratos Wistar
5.
J Clin Med ; 12(24)2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38137797

RESUMO

Multimodal retinal imaging enables the detection of subretinal drusenoid deposits (SDD) with significantly greater accuracy compared to fundus photography. The study aimed to analyze a relationship between the presence of SDD, the clinical picture of AMD, and disease progression in a 3 year follow-up. A total of 602 eyes of 339 patients with a diagnosis of AMD, of which 121 (55%) had SDD confirmed in multimodal retinal imaging, were enrolled in the study. SDD was related to a more advanced stage of AMD (p = 0.008), especially with the presence of geographic atrophy (OR = 4.11, 95% CI 2.02-8.38, p < 0.001). Eyes with SDD presented significantly lower choroidal and retinal thickness (ATC: 210.5 µm, CRT: 277 µm, respectively) and volume (AVC: 0.17 mm3, CRV: 8.29 mm3, p < 0.001, respectively) compared to SDD-negative eyes (ATC: 203 µm, CRT: 277 µm; AVC: 7.08 mm3, 8.54 mm3, p < 0.001). Accordingly, the prevalence of pachychoroids and pachyvessels was significantly lower in the SDD present group than in eyes without SDD (p = 0.004; p = 0.04, respectively). Neither demographic factors, lipid profile, genetic predisposition, systemic vascular disease comorbidities, nor parameters of retinal vessels were affected by the presence of SDD. We found no effect of SDD presence on AMD progression (p = 0.12). The presence of SDD appeared to be related to local rather than systemic factors.

6.
J Clin Med ; 12(21)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37959175

RESUMO

In this paper, the authors present a clinical picture of the diagnosis and current treatment regimens of optic pathway glioma in the pediatric population, with an emphasis on the role of an ophthalmic diagnosis in the differentiation and monitoring of lesions. Glioma is the most common optic nerve tumor in children. MATERIAL: Articles in PubMed, Scholar and Website were reviewed, taking into account current standards of management related to sporadic or NF1-related optic glioma, epidemiology, location, course of the disease, clinical manifestations, histological types of the tumor, genetic predisposition, diagnostic ophthalmic tests currently applicable in therapeutic monitoring of the tumor, neurological diagnosis, therapeutic management and prognosis. The importance of current screening recommendations, in line with standards, was emphasized. RESULTS: Glioma occurs in children most often in the first decade of life. Initially, they may be asymptomatic, and clinically ophthalmic changes are associated with the organ of vision or with systemic changes. Gliomas associated with the NF1 mutation have a better prognosis for sporadic gliomas. Diagnosis includes radiological imaging methods/MRI/ophthalmology/OCT and visual acuity log MAR assessment. The basis of treatment is clinical observation. In the case of disease progression, surgical treatment, chemotherapy and targeted therapy are used. CONCLUSION: Further research into novel techniques for detecting gliomas would allow for early monitoring of the disease.

7.
Exp Psychol ; 70(1): 40-50, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36916698

RESUMO

Previous studies observed differences between men and women in terms of their financial risk-taking. However, these differences may stem not only from the gender of the decision-maker but also from other factors, such as stereotypical gender social roles. Media content exposes both men and women to stereotypical portrayals of their gender, and this might temporarily activate thoughts related to their social roles. A question arises whether such activation might impact the way people make risky financial decisions. The present experimental study investigated whether temporarily activated gender-related social roles influence the risk-taking propensities of men and women (N = 319) in the context of gambling and investment choices. The results show that activating a stereotypically male social role (professional employee) made both men and women more prone to take financial risks relative to a control condition. Furthermore, activating a stereotypically female social role (homemaker) lowered the propensity to take financial risks in both genders for the investment domain and in women only for the gambling domain. This study contributes to the literature on gender differences in economic behavior by showing that researchers should not overlook sociocultural factors.


Assuntos
Jogo de Azar , Assunção de Riscos , Humanos , Masculino , Feminino , Fatores Sexuais
8.
PLoS One ; 17(10): e0276878, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36315562

RESUMO

The research aimed to further develop knowledge on the mechanisms that enhance risk-taking propensities among powerful people. Three studies (N1 = 328, N2 = 388, N3 = 267) investigated the role of optimism in the relationship between sense of power and financial risk-taking, controlling for the state of power. Study 1, correlational, analyzed whether the relationship between sense of power and risky financial choices is serially mediated by general optimism and financial risk perception. The results confirmed the initial hypotheses. The second, experimental, study investigated the role of states of power and lack of power in explaining people's financial decisions as well as their influence on people's situational optimism and perception of risk. The results indicated that people in a state of power differed from people lacking power in terms of their situational optimism and the riskiness of their financial choices; however, they did not differ in terms of risk perception. People having power were more optimistic, invested more, and made riskier gambling choices than those in control conditions and those who lacked power. The third, experimental, study investigated the single and joint moderating effects of the states of optimism and power in explaining the positive relationship between sense of power and risky investing and gambling choices. In line with our expectations, the results of the study showed that the states of power and optimism jointly moderated the positive relationship between the sense of power and risky financial choices. This effect was the strongest under the state of power and optimism conditions and the weakest when lack of power and pessimism were induced; thus boundary conditions for previously observed mechanisms were identified. The results of the research shed light on the way optimism mediates and moderates the effect of power on financial risk-taking and thus contributes to theoretical knowledge of the consequences of power.


Assuntos
Jogo de Azar , Pessimismo , Humanos , Otimismo , Assunção de Riscos
9.
Med Sci Educ ; 32(1): 47-50, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35186430

RESUMO

The integration of basic science into clinical clerkships continues to be a challenge in medical curricula. We developed an integrated session for 3rd year medical students enrolled in OB-Gyn/Pediatric Block. The session focused on transplacental and perinatal infections, and consisted of a student-driven pedagogy activity in which students were required to explain the basic science principles behind the pathophysiology of the clinical presentations, the work-up, and the treatment of the infections. This approach helps students understand how basic science knowledge informs clinical practice and potential increase clerkship-level students' confidence as it makes them serve as leaders of active learning modules. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40670-021-01485-7.

10.
Artigo em Inglês | MEDLINE | ID: mdl-34886560

RESUMO

We present a study (N = 645) investigating how power alters people's propensity to take investment risks in a changing decision context of gains and losses and the intensity of their reactions to this experience. The results indicate that people in a state of power made more risky investment decisions than the control group regardless of prior gain or loss outcome, whereas people lacking power took less investment risk than the control group, regardless of previous outcomes. Moreover, people with power and those lacking power differed in their reactions to gains and losses, with the former reacting more to gains and the latter to losses.


Assuntos
Tomada de Decisões , Investimentos em Saúde , Humanos , Modalidades de Fisioterapia , Assunção de Riscos
11.
Med Clin (Barc) ; 157(10): 464-472, 2021 11 26.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33097207

RESUMO

BACKGROUND: Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a systemic, autoimmune disease. Cytokine dysregulation during active disease and clinical remission, reflects significant immunological activity in various disease stages, and might be responsible for the potential relapse of ANCA-vasculitis. OBJECTIVES: This study aimed to screen serological profiles in active granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA), and to determine their associations with clinical characteristics. MATERIALS AND METHODS: Serum IL-10, IL-12, IL-17, IL-21, IL-23, B cell activating factor (BAFF) concentrations were determined by Quantikine HS ELISA in 71 patients, 47 with GPA and 24 with MPA, and compared with 16 healthy controls. Subsequently, the correlations between serum IL-10, IL-12, IL-17, IL-21, IL-23, BAFF levels, and both laboratory and clinical abnormalities were investigated. RESULTS: BAFF levels were significantly higher in GPA than MPA, and healthy controls. IL-10 and BAFF levels were elevated in GPA patients with pulmonary involvement. Higher BAFF levels might reflect severe GPA. IL-10 and IL-12 levels were higher in MPA than GPA. In MPA, IL-10 levels were highest in patients with short disease duration, and young individuals. IL-12 correlated positively with BVAS and was elevated in patients with cardiovascular involvement and nasal S. aureus carriers. CONCLUSIONS: In MPA, IL-12 correlates positively with disease activity, and is significantly increased in patients with cardiovascular involvement and nasal S. aureus carriers. Increased IL-10 is observed in young MPA patients and in those with short MPA duration. Elevated BAFF and IL-10 levels are associated with pulmonary involvement in GPA. High BAFF levels might reflect severe GPA.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Granulomatose com Poliangiite , Anticorpos Anticitoplasma de Neutrófilos , Citocinas , Humanos , Laboratórios , Staphylococcus aureus
12.
Auris Nasus Larynx ; 47(4): 544-558, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32540054

RESUMO

INTRODUCTION: Otolaryngologists are at very high risk of COVID-19 infection while performing examination or surgery. Strict guidelines for these specialists have not already been provided, while currently available recommendations could presumably change in course of COVID-19 pandemic as the new data increases. OBJECTIVES: This study aimed to synthesize evidence concerning otolaryngology during COVID-19 pandemic. It presents a review of currently existing guidelines and recommendations concerning otolaryngological procedures and surgeries during COVID-19 pandemic, and provides a collective summary of all crucial information for otolaryngologists. It summarizes data concerning COVID-19 transmission, diagnosis, and clinical presentation highlighting the information significant for otolaryngologists. METHODS: The Medline and Web of Science databases were searched without time limit using terms ''COVID-19", "SARS-CoV-2" in conjunction with "head and neck surgery", "otorhinolaryngological manifestations". RESULTS: Patients in stable condition should be consulted using telemedicine options. Only emergency consultations and procedures should be performed during COVID-19 pandemic. Mucosa-involving otolaryngologic procedures are considered high risk procedures and should be performed using enhanced PPE (N95 respirator and full face shield or powered air-purifying respirator, disposable gloves, surgical cap, gown, shoe covers). Urgent surgeries for which there is not enough time for SARS-CoV-2 screening are also considered high risk procedures. These operations should be performed in a negative pressure operating room with high-efficiency particulate air filtration. Less urgent cases should be tested for COVID-19 twice, 48 h preoperatively in 24 h interval. CONCLUSIONS: This review serves as a collection of current recommendations for otolaryngologists for how to deal with their patients during COVID-19 pandemic.


Assuntos
Infecções por Coronavirus/prevenção & controle , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos , Pandemias/prevenção & controle , Equipamento de Proteção Individual , Pneumonia Viral/prevenção & controle , Guias de Prática Clínica como Assunto , Telemedicina , Betacoronavirus , COVID-19 , Infecções por Coronavirus/transmissão , Humanos , Otorrinolaringologistas , Otolaringologia , Pneumonia Viral/transmissão , SARS-CoV-2
13.
Eur Arch Otorhinolaryngol ; 277(6): 1575-1591, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32222803

RESUMO

PURPOSE: Otorhinolaryngological abnormalities are common complications of chronic kidney disease (CKD) and its treatment. The main aim of this study was to provide a brief and precise review of the current knowledge regarding CKD and its treatment-related influence on head and neck organs. METHODS: The Medline and Web of Science databases were searched using the terms "chronic kidney disease", "kidney transplantation", "immunosuppression", "dialysis" in conjunction with "otorhinolaryngological manifestation". Articles that did not address the topics, low-quality studies, case reports, and studies based on nonsignificant cohorts were excluded, and the full text of remaining high-quality, novel articles were examined and elaborated on. RESULTS: Patients with CKD are prone to develop sensorineural hearing loss, tinnitus, recurrent epistaxis, opportunistic infections including oropharyngeal candidiasis or rhino-cerebral mucormycosis, taste and smell changes, phonatory and vestibular dysfunctions, deep neck infections, mucosal abnormalities, gingival hyperplasia, halitosis or xerostomia. Immunosuppressive therapy after kidney transplantation increases the risk of carcinogenesis, both related and not-related to latent viral infection. The most commonly viral-related neoplasms observed in these patients are oral and oropharyngeal cancers, whereas the majority of not-related to viral infection tumors constitute lip and thyroid cancers. CKD-related otorhinolaryngological dysfunctions are often permanent, difficult to control, have a significant negative influence on patient's quality of life, and can be life threatening. CONCLUSION: Patients with CKD suffer from a number of otorhinolaryngological CKD-induced complications. The relationship between several otorhinolaryngological complications and CKD was widely explained, whereas the correlation between the rest of them and CKD remains unclear. Further studies on this subject are necessary.


Assuntos
Transplante de Rim , Insuficiência Renal Crônica , Humanos , Transplante de Rim/efeitos adversos , Qualidade de Vida , Diálise Renal , Insuficiência Renal Crônica/complicações
14.
Ear Nose Throat J ; 98(5): E32-E43, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30966807

RESUMO

Obesity in pediatric population is an important global problem. The prevalence of obesity in children is dramatically rising. According to World Health Organization, about 41 million children under the age of 5 years are obese or overweight worldwide. Overweight and obesity are well-known risk factors for a number of health disorders. Diseases commonly observed in this group of patients are metabolic disorders, type 2 diabetes mellitus, cardiovascular diseases, fatty liver disease, musculoskeletal problems, and many others. The main aim of this study was to present the current knowledge of the association between childhood obesity and common otorhinolaryngological disorders. It is suggested that obese children are more prone to suffer from otorhinolaryngological illnesses than the lean ones. Obesity may predispose to otorhinolaryngological diseases in various ways. It strongly interferes with the immune system (increases serum levels of interleukin 6, tumor necrosis factor, C-reactive protein, and leptin and reduces adiponectin concentration) affecting organs of the upper respiratory tract. Additionally, obesity induces mechanical disorders in the upper airways. According to our review, obesity predisposes to otitis media with effusion, acute otitis media, recurrent otitis media, obstructive sleep apnea, sensorineural hearing loss, adenotonsillar hypertrophy, and post-/perioperative complications after adenotonsillectomy. Obesity in children significantly correlates with both obstructive sleep apnea (OSA) and asthma and constitutes a significant component of "OSA, obesity, asthma" triad.


Assuntos
Otorrinolaringopatias/epidemiologia , Obesidade Infantil/epidemiologia , Criança , Saúde Global , Humanos , Prevalência , Fatores de Risco
15.
PLoS One ; 14(4): e0214396, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30934007

RESUMO

Saving is an important financial behavior that provides an individual with psychological security and boosts his/her overall sense of well-being. For this reason, scientists and practitioners have attempted to understand why some people save when others do not. One of the most common explanations for this phenomenon is that those individuals who earn more should be more willing to save their money. In line with this logic, people who have more money should be more likely to have savings. Considering the results of prior research, we expected objective financial situation (income) to be positively linked to having savings (i.e., propensity to have savings and the exact amount of savings). At the same time, however, we assumed that subjective financial situation (perception) should also be positively related to these variables. To test our assumptions, we conducted a nationwide representative survey (N = 1048) among Polish respondents, asking them about their objective and subjective financial situation. The results of a regression analysis showed that objective financial situation was indeed significantly positively related to having savings. However, subjective financial situation was also positively correlated with having savings (even when we controlled for objective financial situation and demographic variables). We discuss the implications of the links between objective versus subjective financial situations and having savings.


Assuntos
Comportamento/fisiologia , Renda , Saúde Mental/economia , Classe Social , Adolescente , Adulto , Idoso , Tomada de Decisões , Feminino , Objetivos , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
16.
Eur Cytokine Netw ; 30(4): 151-159, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32096477

RESUMO

BACKGROUND: Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is an autoimmune disorder of unknown etiology with dysregulated cytokines levels. OBJECTIVES: The main aim of this study was to assess the clinical correlation between antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis, granulomatosis with polyangiitis (GPA) serum levels of the microscopic polyangiitis (MPA), serum levels of the proinflammatory cytokines, interleukin (IL)-32 and interleukin-6. METHODS: Study included 71 patients, 47 with GPA and 24 with MPA. Serum IL-32 and IL-6 concentrations were analyzed in all patients, and compared with levels observed in 10 controls. IL-32 and IL-6 were evaluated using DuoSet and Quantikine HS ELISA, respectively. IL-32 and IL-6 concentrations were correlated with disease-related clinical and laboratory findings. RESULTS: IL-32 and IL-6 levels were significantly higher in GPA and MPA than in controls, especially IL-32 levels in GPA were elevated. IL-32 concentrations correlated positively with anti-proteinase 3 - ANCA (PR3-ANCA) levels in GPA (P < 0.0001), and with anti-myeloperoxidase ANCA (MPO-ANCA) in MPA (P = 0.049). IL-32 levels correlated positively with disease activity in GPA and MPA (P < 0.0001). GPA patients with pulmonary, cutaneous, and musculoskeletal involvement presented the highest IL-6 serum levels. Cutaneous manifestations correlated positively with IL-6 levels in MPA patients (P = 0.05). ANCA-positive patients with GPA expressed significantly high IL-6 levels (P = 0.036). No significant difference in IL-32 values was observed between ANCA-positive and ANCA-negative patients. CONCLUSIONS: Patients with GPA and MPA present higher serum IL-32 and IL-6 levels than controls. IL-32 levels correlate positively with disease activity.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/sangue , Granulomatose com Poliangiite/diagnóstico , Interleucina-6/sangue , Interleucinas/sangue , Poliangiite Microscópica/diagnóstico , Adulto , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Diagnóstico Diferencial , Feminino , Expressão Gênica , Granulomatose com Poliangiite/sangue , Granulomatose com Poliangiite/genética , Granulomatose com Poliangiite/imunologia , Humanos , Interleucina-6/genética , Interleucina-6/imunologia , Interleucinas/genética , Interleucinas/imunologia , Masculino , Poliangiite Microscópica/sangue , Poliangiite Microscópica/genética , Poliangiite Microscópica/imunologia , Pessoa de Meia-Idade , Mieloblastina/sangue , Mieloblastina/genética , Mieloblastina/imunologia , Peroxidase/sangue , Peroxidase/genética , Peroxidase/imunologia , Índice de Gravidade de Doença
17.
ChemSusChem ; 12(3): 639-650, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30350463

RESUMO

Calcium-modified titania supported Ru catalysts were synthesized and evaluated for the hydrogenation of levulinic acid with formic acid as an internal hydrogen source and water as a green solvent. A new elegant photoassisted method was developed for the synthesis of uniform-size and evenly distributed Ru particles on the titania surface. Compared with the counterpart catalysts prepared by classical wet impregnation, enhanced levulinic acid conversion and γ-valerolactone yield were obtained and further improved through modification of the support by introduction of calcium into the titania support. This synthesis approach resulted in a change of the surface and bulk properties of the support, namely a decrease in the anatase crystallite size and the formation of a new calcium titanate phase. As a consequence, the properties of the catalysts were modified, and smaller ruthenium particles that had stronger interactions with the support were obtained. This affected the strength of the CO adsorption on the catalyst surface and facilitated the reaction performance. The optimum size of Ru particles that allowed for most efficient levulinic acid conversion was established.

18.
Materials (Basel) ; 11(11)2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30463255

RESUMO

Ru/TiO2 are promising heterogeneous catalysts in different key-reactions taking place in the catalytic conversion of biomass towards fuel additives, biofuels, or biochemicals. TiO2 supported highly dispersed nanometric-size metallic Ru catalysts were prepared at room temperature via a solar light induced photon-assisted one-step synthesis in liquid phase, far smaller Ru nanoparticles with sharper size distribution being synthesized when compared to the catalysts that were prepared by impregnation with thermal reduction in hydrogen. The underlying strategy is based on the redox photoactivity of the TiO2 semi-conductor support under solar light for allowing the reduction of metal ions pre-adsorbed at the host surface by photogenerated electrons from the conduction band of the semi-conductor in order to get a fine control in terms of size distribution and dispersion, with no need of chemical reductant, final thermal treatment, or external hydrogen. Whether acetylacetonate or chloride was used as precursor, 0.6 nm sub-nanometric metallic Ru particles were synthesized on TiO2 with a sharp size distribution at a low loading of 0.5 wt.%. Using the chloride precursor was necessary for preparing Ru/TiO2 catalysts with a 0.8 nm sub-nanometric mean particle size at 5 wt.% loading, achieved in basic conditions for benefitting from the enhanced adsorption between the positively-charged chloro-complexes and the negatively-charged TiO2 surface. Remarkably, within the 0.5⁻5 wt.% range, the Ru content had only a slight influence on the sub-nanometric particle size distribution, thanks to the implementation of suitable photo-assisted synthesis conditions. We demonstrated further that a fine control of the metal Ru nanoparticle size on the TiO2 support was possible via a controlled nanocluster growth under irradiation, while the nanoparticles revealed a good resistance to thermal sintering.

19.
Front Psychol ; 9: 920, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29922210

RESUMO

Willingness to take risk is one of the most important aspects of personal financial decisions, especially those regarding investments. Recent studies show that one's perception of time, specifically the individual level of Present Hedonistic and Future Time Perspectives (TPs), influence risky financial choices. This was demonstrated for both, Time Perspective treated as an individual trait and for experimentally induced Time Perspectives. However, on occasion, people might find themselves under the joint influence of both, chronic and situational Time Perspectives and little is known about interactions between them. The paper focuses on the interplay between chronic and induced levels of Future and Present Hedonistic TPs in explaining people's propensity to take investment risks. An experimental study using a Polish national random-quota sample was conducted. The results showed that situationally induced Future TP lowered the preferred level of portfolio riskiness while situationally induced Present Hedonistic TPs resulted in exactly the opposite effect, and that the higher level of chronic Present Hedonistic TP was linked to higher investment risk preferences. The role of the chronic Present Hedonistic TP was moderated by the situationally induced Future (approaching significance) and Present Hedonistic TPs. The induction of these TPs resulted in reduction of the propensity to take investment risks. The study adds to the literature on psychological factors influencing the propensity to take financial risk. The results are also important for researchers who experimentally manipulate variables that might be also considered as chronic traits. They indicate that whether the manipulation is congruent with one's natural tendencies may have a differential impact on subsequent measures.

20.
Adv Clin Exp Med ; 26(5): 857-864, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29068584

RESUMO

Ureteropelvic junction obstruction (UPJO) causes a reduction in the urine flow from the renal pelvis into the ureter. Untreated UPJO may cause hydronephrosis, chronic infection or urolithiasis and will often result in progressive deterioration of renal function. Most cases of UPJO are congenital; however, the disease can be clinically silent until adulthood. Other causes, both intrinsic and extrinsic, are acquired and include urolithiasis, post-operative/inflammatory/ischemic stricture, fibroepithelial polyps, adhesions and malignancy. In the past, the most frequent symptom of UPJO in neonates and infants was a palpable flank mass. Nowadays, thanks to the widespread use of maternal and prenatal ultrasound examinations, asymptomatic hydronephrosis is diagnosed very early. In adults and older children symptoms may include intermittent abdominal or flank pain, nausea, vomiting and hematuria. In addition to high specificity and sensitivity in detecting UPJO, modern technologically advanced equipment such as ultrasound, magnetic resonance imaging and computed tomography provides a lot of information about the function of the affected kidney and the anatomy of the surrounding tissues. Treatment options for UPJO include a wide spectrum of approaches, from active surveillance or minimally invasive endourologic techniques to open, laparoscopic or robotic pyeloplasty. The main goal of therapy is to relieve symptoms and maintain or improve renal function, but it is difficult to define treatment success after UPJO therapy.


Assuntos
Hidronefrose/etiologia , Pelve Renal/fisiopatologia , Obstrução Ureteral/complicações , Bexiga Urinária/fisiopatologia , Urodinâmica , Humanos , Hidronefrose/diagnóstico , Hidronefrose/fisiopatologia , Hidronefrose/terapia , Prognóstico , Fatores de Risco , Obstrução Ureteral/diagnóstico , Obstrução Ureteral/fisiopatologia , Obstrução Ureteral/terapia
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