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1.
Arch Anim Nutr ; 77(6): 497-511, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38189144

RESUMO

The impacts of different dietary levels of rice gluten meal (RGM) on growth performance, digestibility, carcass characteristics, and blood traits of growing New Zealand White (NZW) rabbits were studied. One hundred and twenty, 6 weeks old weaned male rabbits (body weight; 682 [g] ± 23) were randomly allotted into four groups. The control diet contained 160 [g/kg] soybean meal (SBM), while the other three diets were obtained by replacing 40, 80, and 120 [g/kg] SBM with RGM (RGM40, RGM80, and RGM120, respectively). The results showed that RGM contained higher levels of dry matter (DM), crude protein (CP), ether extract (EE), ash, and gross energy than SBM. RGM contained a high level of arginine followed by leucine and valine as essential amino acids and high levels of glutamic, aspartic acid, and alanine as non-essential amino acids. The obtained results showed that the final body weight of rabbits fed diets containing 40, 80, and 120 [g/kg] RGM was higher than those fed the control diet. The daily weight gain of rabbits fed RGM diets increased (p < 0.05) by 10.50%, 6.50%, and 10.00%, respectively, compared to the control group. Rabbits fed RGM80 showed the highest (p < 0.05) digestibility of DM, organic matter (OM), EE, neutral detergent fibre (NDF), and acid detergent fibre (ADF) compared to the other tested levels. Rabbits fed RGM120 had the highest (p < 0.05) digestible energy (DE) and digestible crude protein (DCP) values. RGM inclusion levels of 40 and 80 [g/kg] increased (p < 0.05) plasma total protein and albumin compared to the control group. Rabbits fed a diet containing RGM40 had the highest (p < 0.05) globulin level. The highest (p < 0.05) plasma urea concentration level was measured in the rabbit group fed the RGM120 diet. Conclusively, RGM could be a valuable ingredient for growing rabbits, as at all the tested levels improved growth performance, digestibility, and nutritional values.


Assuntos
Dieta , Oryza , Coelhos , Masculino , Animais , Dieta/veterinária , Glutens , Detergentes , Farinha , Digestão , Ração Animal/análise , Aumento de Peso , Fenômenos Fisiológicos da Nutrição Animal
2.
Cancer Causes Control ; 32(3): 261-269, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33394204

RESUMO

PURPOSE: To investigate men's experiences of receiving external-beam radiotherapy (EBRT) with neoadjuvant Androgen Deprivation Therapy (ADT) for localized prostate cancer (LPCa) in the ProtecT trial. METHODS: A longitudinal qualitative interview study was embedded in the ProtecT RCT. Sixteen men with clinically LPCa who underwent EBRT in ProtecT were purposively sampled to include a range of socio-demographic and clinical characteristics. They participated in serial in-depth qualitative interviews for up to 8 years post-treatment, exploring experiences of treatment and its side effects over time. RESULTS: Men experienced bowel, sexual, and urinary side effects, mostly in the short term but some persisted and were bothersome. Most men downplayed the impacts, voicing expectations of age-related decline, and normalizing these changes. There was some reticence to seek help, with men prioritizing their relationships and overall health and well-being over returning to pretreatment levels of function. Some unmet needs with regard to information about treatment schedules and side effects were reported, particularly among men with continuing functional symptoms. CONCLUSIONS: These findings reinforce the importance of providing universal clear, concise, and timely information and supportive resources in the short term, and more targeted and detailed information and care in the longer term to maintain and improve treatment experiences for men undergoing EBRT.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Idoso , Antagonistas de Androgênios/efeitos adversos , Terapia Combinada/efeitos adversos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Lesões por Radiação/epidemiologia , Lesões por Radiação/etiologia , Inquéritos e Questionários
3.
BMC Cancer ; 20(1): 971, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028256

RESUMO

BACKGROUND: Optimal management strategies for clinically localised prostate cancer are debated. Using median 10-year data from the largest randomised controlled trial to date (ProtecT), the lifetime cost-effectiveness of three major treatments (radical radiotherapy, radical prostatectomy and active monitoring) was explored according to age and risk subgroups. METHODS: A decision-analytic (Markov) model was developed and informed by clinical input. The economic evaluation adopted a UK NHS perspective and the outcome was cost per Quality-Adjusted Life Year (QALY) gained (reported in UK£), estimated using EQ-5D-3L. RESULTS: Costs and QALYs extrapolated over the lifetime were mostly similar between the three randomised strategies and their subgroups, but with some important differences. Across all analyses, active monitoring was associated with higher costs, probably associated with higher rates of metastatic disease and changes to radical treatments. When comparing the value of the strategies (QALY gains and costs) in monetary terms, for both low-risk prostate cancer subgroups, radiotherapy generated the greatest net monetary benefit (£293,446 [95% CI £282,811 to £299,451] by D'Amico and £292,736 [95% CI £284,074 to £297,719] by Grade group 1). However, the sensitivity analysis highlighted uncertainty in the finding when stratified by Grade group, as radiotherapy had 53% probability of cost-effectiveness and prostatectomy had 43%. In intermediate/high risk groups, using D'Amico and Grade group > = 2, prostatectomy generated the greatest net monetary benefit (£275,977 [95% CI £258,630 to £285,474] by D'Amico and £271,933 [95% CI £237,864 to £287,784] by Grade group). This finding was supported by the sensitivity analysis. Prostatectomy had the greatest net benefit (£290,487 [95% CI £280,781 to £296,281]) for men younger than 65 and radical radiotherapy (£201,311 [95% CI £195,161 to £205,049]) for men older than 65, but sensitivity analysis showed considerable uncertainty in both findings. CONCLUSION: Over the lifetime, extrapolating from the ProtecT trial, radical radiotherapy and prostatectomy appeared to be cost-effective for low risk prostate cancer, and radical prostatectomy for intermediate/high risk prostate cancer, but there was uncertainty in some estimates. Longer ProtecT trial follow-up is required to reduce uncertainty in the model. TRIAL REGISTRATION: Current Controlled Trials number, ISRCTN20141297: http://isrctn.org (14/10/2002); ClinicalTrials.gov number, NCT02044172: http://www.clinicaltrials.gov (23/01/2014).


Assuntos
Análise Custo-Benefício/métodos , Prostatectomia/economia , Neoplasias da Próstata/radioterapia , Idoso , Protocolos Clínicos , Humanos , Masculino , Neoplasias da Próstata/patologia , Fatores de Tempo
4.
N Engl J Med ; 375(15): 1425-1437, 2016 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-27626365

RESUMO

BACKGROUND: Robust data on patient-reported outcome measures comparing treatments for clinically localized prostate cancer are lacking. We investigated the effects of active monitoring, radical prostatectomy, and radical radiotherapy with hormones on patient-reported outcomes. METHODS: We compared patient-reported outcomes among 1643 men in the Prostate Testing for Cancer and Treatment (ProtecT) trial who completed questionnaires before diagnosis, at 6 and 12 months after randomization, and annually thereafter. Patients completed validated measures that assessed urinary, bowel, and sexual function and specific effects on quality of life, anxiety and depression, and general health. Cancer-related quality of life was assessed at 5 years. Complete 6-year data were analyzed according to the intention-to-treat principle. RESULTS: The rate of questionnaire completion during follow-up was higher than 85% for most measures. Of the three treatments, prostatectomy had the greatest negative effect on sexual function and urinary continence, and although there was some recovery, these outcomes remained worse in the prostatectomy group than in the other groups throughout the trial. The negative effect of radiotherapy on sexual function was greatest at 6 months, but sexual function then recovered somewhat and was stable thereafter; radiotherapy had little effect on urinary continence. Sexual and urinary function declined gradually in the active-monitoring group. Bowel function was worse in the radiotherapy group at 6 months than in the other groups but then recovered somewhat, except for the increasing frequency of bloody stools; bowel function was unchanged in the other groups. Urinary voiding and nocturia were worse in the radiotherapy group at 6 months but then mostly recovered and were similar to the other groups after 12 months. Effects on quality of life mirrored the reported changes in function. No significant differences were observed among the groups in measures of anxiety, depression, or general health-related or cancer-related quality of life. CONCLUSIONS: In this analysis of patient-reported outcomes after treatment for localized prostate cancer, patterns of severity, recovery, and decline in urinary, bowel, and sexual function and associated quality of life differed among the three groups. (Funded by the U.K. National Institute for Health Research Health Technology Assessment Program; ProtecT Current Controlled Trials number, ISRCTN20141297 ; ClinicalTrials.gov number, NCT02044172 .).


Assuntos
Nível de Saúde , Prostatectomia , Neoplasias da Próstata/terapia , Qualidade de Vida , Conduta Expectante , Idoso , Doenças do Sistema Digestório , Disfunção Erétil , Humanos , Análise de Intenção de Tratamento , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Inquéritos e Questionários , Resultado do Tratamento , Doenças Urológicas
5.
Phys Chem Chem Phys ; 20(44): 28287-28299, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30398493

RESUMO

Two processes for crosslinking polyvinyl alcohol (PVA) with sulfosuccinic acid (SSA) and thermal crosslinking were used to fabricate a proton exchange membrane (PEM). Such PEMs are used in different fields involving fuel cell applications. The crosslinking reaction between PVA and SSA was confirmed using Fourier-transform infrared (FTIR) spectroscopy. The characterization of the prepared membranes, namely, ion exchange capacity (IEC), thermal analyses, water uptake, and ionic conductivity, was carried out. The IEC of the prepared membranes was found to be between 0.084 and 2.086 mmol g-1, resulting in an essential increase in the ionic conductivity. It was observed that the ionic conductivity was in the range of 0.003-0.023 S cm-1, depending on both temperature and SSA content. From the thermogravimetric analysis (TGA) results, it was revealed that the thermal stability of the crosslinked membranes improved. Moreover, water uptake decreased with increasing SSA content. Positron annihilation lifetime spectroscopy (PALS) was used to study the microstructure of the PVA/SSA membranes and their distribution at different ambient temperatures and relative humidity (RH) values. At room temperature, no significant change was observed in the free-volume holes up to 15 wt% SSA; thereafter, the size of the free-volume holes increased with the SSA content. The PALS results show that at different humidity values, the size of the free-volume holes for crosslinked PVA/SSA membranes is lower than those for Nafion membranes, i.e., the gas permeability for the prepared PVA/SSA membranes is less than that for the Nafion membrane. In addition, a strong correlation between the water uptake, ionic conductivity, tensile strength, and free-volume holes was observed.

6.
J Relig Health ; 57(6): 2224-2229, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29116582

RESUMO

BACKGROUND: The delusional misidentification syndromes (DMS) include a myriad of discrete but related syndromes, which have wide spectrum anomalies of familiarity. Several misidentification syndromes have been described in the psychiatric literature, the most common of these delusions are: the Capgras syndrome; the Fregoli syndrome; the syndrome of inter-metamorphosis; reduplicative paramnesia; and environmental reduplication. CASE PRESENTATION: The reported case highlights the emergence of late onset first episode psychosis in a Middle Eastern 65-year-old female who has no previous psychiatric history. The nature of psychosis was mainly delusions of misidentification and persecution. DISCUSSION: DMS are relatively rare and occur predominantly in association with schizophrenia and affective psychosis. Between 25 and 40% are associated with organic conditions such as dementia, head injuries, brain tumors, and epilepsy. Only three cases of misidentification of sacred places have been reported previously in the literature. This case report is the first to present a DMS, emerging as a late onset first episode psychosis during the sacred journey of Hajj. CLINICAL IMPLICATIONS: The reported case highlights the importance of early recognition and treatment of mental health conditions that may appear de novo during the Hajj sacred journey. Readily available psychiatric resources, psychotropic medications, and psycho-education may be pivotal in ensuring mental well-being of pilgrims, which is fundamental to maintain the mental capacity required for completing these journeys.


Assuntos
Síndrome de Capgras/psicologia , Delusões/diagnóstico , Transtornos Psicóticos/diagnóstico , Idoso , Delusões/psicologia , Feminino , Humanos , Islamismo , Transtornos Psicóticos/psicologia
7.
Br J Cancer ; 116(2): 227-236, 2017 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-28006818

RESUMO

BACKGROUND: Recent evidence suggests that bone-related parameters are the main prognostic factors for overall survival in advanced prostate cancer (PCa), with elevated circulating levels of alkaline phosphatase (ALP) thought to reflect the dysregulated bone formation accompanying distant metastases. We have identified that PCa cells express ALPL, the gene that encodes for tissue nonspecific ALP, and hypothesised that tumour-derived ALPL may contribute to disease progression. METHODS: Functional effects of ALPL inhibition were investigated in metastatic PCa cell lines. ALPL gene expression was analysed from published PCa data sets, and correlated with disease-free survival and metastasis. RESULTS: ALPL expression was increased in PCa cells from metastatic sites. A reduction in tumour-derived ALPL expression or ALP activity increased cell death, mesenchymal-to-epithelial transition and reduced migration. Alkaline phosphatase activity was decreased by the EMT repressor Snail. In men with PCa, tumour-derived ALPL correlated with EMT markers, and high ALPL expression was associated with a significant reduction in disease-free survival. CONCLUSIONS: Our studies reveal the function of tumour-derived ALPL in regulating cell death and epithelial plasticity, and demonstrate a strong association between ALPL expression in PCa cells and metastasis or disease-free survival, thus identifying tumour-derived ALPL as a major contributor to the pathogenesis of PCa progression.


Assuntos
Fosfatase Alcalina/fisiologia , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Fosfatase Alcalina/genética , Animais , Morte Celular/genética , Movimento Celular/genética , Células Cultivadas , Progressão da Doença , Intervalo Livre de Doença , Células HEK293 , Humanos , Masculino , Camundongos , Metástase Neoplásica , Neoplasias da Próstata/genética
8.
Colorectal Dis ; 18(11): O427-O431, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27620339

RESUMO

AIM: In advanced pelvic cancer it may be necessary to perform a total pelvic exenteration. In such cases urinary tract reconstruction is usually achieved with the creation of an ileal conduit with a urinary stoma on the right side of the patient's abdomen and an end colostomy separately on the left. The potential morbidity from a second stoma may be avoided by the use of a double-barrelled wet colostomy (DBWC), as a single stoma. Another advantage is the possibility of using a vertical rectus abdominis muscle flap for perineal reconstruction. METHOD: All patients undergoing formation of a DBWC were included. RESULT: A DBWC was formed in 10 patients. One patient underwent formation of a double-barrelled wet ileostomy. CONCLUSIONS: In this technical note we present our early experience in 11 cases and a video of DBWC formation in a male patient.


Assuntos
Colostomia/métodos , Recidiva Local de Neoplasia/cirurgia , Exenteração Pélvica/métodos , Neoplasias Retais/cirurgia , Adulto , Idoso , Feminino , Humanos , Ileostomia/métodos , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Neoplasias Retais/patologia , Retalhos Cirúrgicos , Derivação Urinária/métodos , Sistema Urinário/cirurgia , Adulto Jovem
9.
Ann Oncol ; 26(4): 756-761, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25595936

RESUMO

BACKGROUND: A rare recurrent missense variant in HOXB13 (rs138213197/G84E) was recently reported to be associated with hereditary prostate cancer. Population-based studies have established that, since the frequency of this single-nucleotide polymorphism (SNP) varies between geographic regions, the associated proportion of prostate cancer (PrCa) risk contribution is also highly variable by country. PATIENTS AND METHODS: This is the largest comprehensive case-control study assessing the prevalence of the HOXB13 G84E variant to date and is the first in the UK population. We genotyped 8652 men diagnosed with PrCa within the UK Genetic Prostate Cancer Study (UKGPCS) and 5252 healthy men from the UK ProtecT study. RESULTS: HOXB13 G84E was identified in 0.5% of the healthy controls and 1.5% of the PrCa cases, and it was associated with a 2.93-fold increased risk of PrCa [95% confidence interval (CI) 1.94-4.59; P = 6.27 × 10(-8)]. The risk was even higher among men with family history of PrCa [odds ratio (OR) = 4.53, 95% CI 2.86-7.34; P = 3.1 × 10(-8)] and in young-onset PrCa (diagnosed up to the age of 55 years; OR = 3.11, 95% CI 1.98-5.00; P = 6.1 × 10(-7)). There was no significant association between Gleason Score, presenting prostate specific antigen, tumour-node-metastasis (TNM) stage or NCCN risk group and carrier status. HOXB13 G84E was not associated with overall or cancer-specific survival. We found that the polygenic PrCa risk score (PR score), calculated using the 71 known single-nucleotide polymorphisms (SNPs) associated with PrCa and the HOXB13 G84E variant act multiplicatively on PrCa risk. Based on the estimated prevalence and risk, this rare variant explains ∼1% of the familial risk of PrCa in the UK population. CONCLUSIONS: The clinical importance of HOXB13 G84E in PrCa management has not been established. This variant was found to have no effect on prognostic implications but could be used for stratifying screening, by identifying men at high risk. CLINICAL TRIALS NUMBERS: Prostate Testing for Cancer and Treatment (ProtecT): NCT02044172. UK GENETIC PROSTATE CANCER STUDY: Epidemiology and Molecular Genetics Studies (UKGPCS): NCT01737242.


Assuntos
Predisposição Genética para Doença , Mutação em Linhagem Germinativa/genética , Proteínas de Homeodomínio/genética , Polimorfismo de Nucleotídeo Único/genética , Próstata/metabolismo , Neoplasias da Próstata/genética , Idoso , Estudos de Casos e Controles , Seguimentos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prevalência , Prognóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Fatores de Risco , Taxa de Sobrevida , Reino Unido
10.
J Ment Health ; 24(5): 289-93, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25992868

RESUMO

BACKGROUND: Since the beginning of the Egyptian political conflict, Tahrir Square has been the epicentre of intense political violence. Students attending schools located near this square witnessed and/or directly experienced the consequences of a series of violent events. AIM: This study will investigate the presence of psychiatric symptoms in children attending these schools to explore patterns of responses according to their perceptions of the revolution on their lives, adjusted for, gender and socio-economic status. METHOD: A descriptive cross-sectional study conducted with 515 Egyptian school children attending government, experimental, and private language schools located within 1 km of Tahrir Square. To assess psychiatric symptoms in these children, a specially designed questionnaire was used to detect, depression, anxiety, and post-traumatic stress disorder (PTSD) symptoms and impairments. RESULTS: Children attending schools near Tahrir Square showed high rates of depression, PTSD and anxiety symptoms. The risk factors identified for developing psychiatric symptoms were a negative perception of the effect of the revolution, knowing someone exposed to trauma during the events, female gender and low socio-economic class. DISCUSSION: These results highlight the need for large-scale studies to explore the consequences of ongoing political violence on children and to establish baseline data on the mental health of Egyptian children.


Assuntos
Conflitos Armados/psicologia , Exposição à Violência/psicologia , Saúde Mental , Adolescente , Ansiedade/epidemiologia , Criança , Estudos Transversais , Depressão/epidemiologia , Egito , Exposição à Violência/estatística & dados numéricos , Feminino , Humanos , Masculino , Saúde Mental/estatística & dados numéricos , Política , Fatores de Risco , Fatores Sexuais , Fatores Socioeconômicos , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Estudantes/psicologia , Inquéritos e Questionários
11.
Br J Cancer ; 110(12): 2829-36, 2014 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-24867688

RESUMO

BACKGROUND: Screening for prostate cancer continues to generate controversy because of concerns about over-diagnosis and unnecessary treatment. We describe the rationale, design and recruitment of the Cluster randomised triAl of PSA testing for Prostate cancer (CAP) trial, a UK-wide cluster randomised controlled trial investigating the effectiveness and cost-effectiveness of prostate-specific antigen (PSA) testing. METHODS: Seven hundred and eighty-five general practitioner (GP) practices in England and Wales were randomised to a population-based PSA testing or standard care and then approached for consent to participate. In the intervention arm, men aged 50-69 years were invited to undergo PSA testing, and those diagnosed with localised prostate cancer were invited into a treatment trial. Control arm practices undertook standard UK management. All men were flagged with the Health and Social Care Information Centre for deaths and cancer registrations. The primary outcome is prostate cancer mortality at a median 10-year-follow-up. RESULTS: Among randomised practices, 271 (68%) in the intervention arm (198,114 men) and 302 (78%) in the control arm (221,929 men) consented to participate, meeting pre-specified power requirements. There was little evidence of differences between trial arms in measured baseline characteristics of the consenting GP practices (or men within those practices). CONCLUSIONS: The CAP trial successfully met its recruitment targets and will make an important contribution to international understanding of PSA-based prostate cancer screening.


Assuntos
Detecção Precoce de Câncer/economia , Detecção Precoce de Câncer/métodos , Seleção de Pacientes , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico , Idoso , Análise Custo-Benefício , Inglaterra , Clínicos Gerais , Humanos , Masculino , Programas de Rastreamento/economia , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Neoplasias da Próstata/mortalidade , Projetos de Pesquisa , País de Gales
12.
Sci Rep ; 14(1): 16501, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39019938

RESUMO

With a rapid increase in industrial growth around the world, the demand for an entirely novel category of nanoparticles and technologies for wastewater treatment has become a key concern for environmental protection. Recently, hybrids of layered double hydroxides (LDH), particularly those containing LDH, have gained attention as potential nanoscale adsorbents for water treatment. Recent research has shown that LDH-containing composites are interesting versatile materials with the ability to be used in energy storage, photocatalysis, nanocomposites, and water treatment. In the current work, LDH-containing composites were utilized as adsorbents for the purpose of purifying water. The adsorbents investigated are Zn-Co-Fe/LDH/Chitosan-in situ sample preparation (LDH/CS1) and Zn-Co-Fe/LDH/Chitosan-ex situ sample preparation (LDH/CS2). Furthermore, LDH/CS1 and LDH/CS2 were investigated for wastewater treatment from methyl orange dye (MO) with various adsorption conditions. When the initial MO concentration was 20 mg/L and the amount of adsorbent was 0.1 g, the removal efficiency reached 72.8 and 91.7% for LDH/CS1 and LDH/CS2, respectively. The MO's maximum adsorption capabilities are 160.78 and 165.89 mg/g for LDH/CS1 and LDH/CS2, respectively, which is much greater than that of comparable commercial adsorbents. MO adsorption onto LDH/CS1 and LDH/CS2 was best characterized by the pseudo-second-order kinetic model. The equilibrium adsorption data was followed by the Freundlich and Langmuir models. The adsorption is favorable as evidenced by the equilibrium parameter RL values for MO adsorption onto LDH/CS1 and LDH/CS2, which were 0.227 and 0.144, respectively. Using the free volume distribution method and the positron annihilation lifetime technique, the nanostructure of the materials was examined.

13.
Sci Rep ; 14(1): 1092, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212527

RESUMO

In this study, a novel proton-conducting polymer electrolyte membrane based on a mixture of polyvinyl alcohol (PVA)/polyvinyl pyrrolidone (PVP) (1:1) mixed with different ratios of graphene oxide (GO) and plasma-treated was successfully synthesized. Dielectric barrier dielectric (DBD) plasma was used to treat the prepared samples at various dose rates (2, 4, 6, 7, 8, and 9 min) and at fixed power input (2 kV, 50 kHz). The treated samples (PVA/PVP:GO wt%) were soaked in a solution of styrene and tetrahydrofuran (70:30 wt%) with 5 × 10-3 g of benzoyl peroxide as an initiator in an oven at 60 °C for 12 h and then sulfonated to create protonic membranes (PVA/PVP-g-PSSA:GO). The impacts of graphene oxide (GO) on the physical, chemical, and electrochemical properties of plasma-treated PVA/PVP-g-PSSA:x wt% GO membranes (x = 0, 0.1, 0.2, and 0.3) were investigated using different techniques. SEM results showed a better dispersion of nanocomposite-prepared membranes; whereas the AFM results showed an increase in total roughness with increasing the content of GO. FTIR spectra provide more information about the structural variation arising from the grafting and sulfonation processes to confirm their occurrence. The X-ray diffraction pattern showed that the PVA/PVP-g-PSSA:x wt% GO composite is semi-crystalline. As the level of GO mixing rises, the crystallinity of the mixes decreases. According to the TGA curve, the PVA/PVP-g-PSSA:x wt% GO membranes are chemically stable up to 180 °C which is suitable for proton exchange membrane fuel cells. Water uptake (WU) was also measured and found to decrease from 87.6 to 63.3% at equilibrium with increasing GO content. Ion exchange capacity (IEC) was calculated, and the maximum IEC value was 1.91 meq/g for the PVA/PVP-g-PSSA: 0.3 wt% GO composite membrane. At room temperature, the maximum proton conductivity was 98.9 mS/cm for PVA/PVP-g-PSSA: 0.3 wt% GO membrane. In addition, the same sample recorded a methanol permeability of 1.03 × 10-7 cm2/s, which is much less than that of Nafion NR-212 (1.63 × 10-6 cm2/s). These results imply potential applications for modified polyelectrolytic membranes in fuel cell technology.

14.
J Lipid Res ; 54(3): 852-858, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23264677

RESUMO

Malondialdehyde (MDA) is one of the most commonly reported biomarkers of lipid peroxidation in clinical studies. The reaction of thiobarbituric acid (TBA) with MDA to yield a pink chromogen attributable to an MDA-TBA2 adduct is a common assay approach with products being quantified by ultraviolet-Vis assay as nonspecific TBA-reactive substances (TBARS) or chromatographically as MDA. The specificity of the TBARS assay was compared with both chromatographic assays for total plasma MDA. The levels of total plasma MDA were significantly lower than the plasma TBARS in each of the samples examined, and interestingly, the interindividual variation apparent in the level of plasma MDA was not evident in the plasma TBARS assay. Each of the four online chromatographic detectors yielded a precise, sensitive, and accurate determination of total plasma MDA, and selected-ion monitoring was the most-accurate assay (101.3%, n = 4). The online diode array detectors provided good assay specificity (peak purity index of 999), sensitivity, precision, and accuracy. This research demonstrates the inaccuracy that is inherent in plasma TBARS assays, which claim to quantify MDA, and it is proposed that the TBARS approach may limit the likelihood of detecting true differences in the level of lipid peroxidation in clinical studies.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Malondialdeído/sangue , Humanos , Peroxidação de Lipídeos , Espectrometria de Massas , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
15.
Prostate ; 73(4): 398-408, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22996647

RESUMO

BACKGROUND: Dystroglycan is a ubiquitously expressed cell adhesion molecule frequently found to be altered or reduced in adenocarcinomas, however the mechanisms or consequences of dystroglycan loss have not been studied extensively. METHODS: We examined the consequence of overexpression or RNAi depletion of dystroglycan on properties of in vitro growth migration and invasion of LNCaP, PC3, and DU145 prostate cancer cell lines. RESULTS: Using LNCaP cells we observed cell density-dependent changes in ß-dystroglycan with the appearance of several lower molecular weight species ranging in size from 43 to 26 kDa. The bands of 31 and 26 kDa were attributed to proteolysis, whereas bands between 43 and 38 kDa were a consequence of mis-glycosylation. The localization of ß-dystroglycan in LNCaP colonies in culture also varied, cells with a mesenchymal appearance at the periphery of the colony had more pronounced membrane localization of dystroglycan. Whereas some cells demonstrated nuclear dystroglycan. Increased dystroglycan levels were inhibitory to growth in soft agar but promoted Matrigel invasion, whereas reduced dystroglycan levels promoted growth in soft agar but inhibited invasion. Similar results were also obtained for PC3 and DU145 cells. CONCLUSIONS: This study suggests that changes in ß-dystroglycan distribution within the cell and/or the loss of dystroglycan during tumorigenesis, through a combination of proteolysis and altered glycosylation, leads to an increased ability to grow in an anchorage independent manner, however dystroglycan may need to be re-expressed for cell invasion and metastasis to occur.


Assuntos
Distroglicanas/fisiologia , Invasividade Neoplásica/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/fisiopatologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Humanos , Masculino , Neoplasias da Próstata/fisiopatologia , Células Tumorais Cultivadas
16.
Br J Cancer ; 108(4): 748-54, 2013 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-23361058

RESUMO

Many cancers display increased expression of histone deacetylases (HDACs) and therefore transcriptionally inactive chromatin, resulting in the downregulation of genes including tumour suppressor and DNA repair genes. Histone deacetylase inhibitors (HDACi) are a heterogeneous group of epigenetic therapeutics, showing promising anticancer effects in both pre-clinical and clinical settings, in particular the effect of radiosensitisation when administered in combination with radiotherapy. Radiotherapy remains one of the most common forms of cancer treatment, leading to cell death through the induction of DNA double-strand breaks (DSBs). Cells have developed mechanisms to repair such DSB through two major pathways: non-homologous end-joining and homologous recombination. Here, we explore the current evidence for the use of HDACi in combination with irradiation, focusing on the effects of HDACi on DNA damage signalling and repair in vitro. In addition, we summarise the clinical evidence for using HDACi with radiotherapy, a growing area of interest with great potential clinical utility.


Assuntos
Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Inibidores de Histona Desacetilases/uso terapêutico , Neoplasias/tratamento farmacológico , Radiossensibilizantes/uso terapêutico , Ensaios Clínicos como Assunto , Terapia Combinada , Humanos , Neoplasias/genética , Neoplasias/radioterapia , Transdução de Sinais/efeitos dos fármacos
17.
Phys Chem Chem Phys ; 15(27): 11494-500, 2013 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-23748745

RESUMO

To understand the relationship between surface morphology and proton conduction of polymer electrolyte thin films, perfluorinated ionomer Nafion® thin films were prepared on different substrates such as glassy carbon (GC), hydrophilic-GC (H-GC), and platinum (Pt) as models for the ionomer film within a catalyst layer. Atomic force microscopy coupled with an electrochemical (e-AFM) technique revealed that proton conduction decreased with film thickness; an abrupt decrease in proton conductance was observed when the film thickness was less than ca. 10 nm on GC substrates in addition to a significant change in surface morphology. Furthermore, thin films prepared on H-GC substrates with UV-ozone treatment exhibited higher proton conduction than those on untreated GC substrates. However, Pt substrates exhibited proton conduction comparable to that of GCs for films thicker than 20 nm; a decrease in proton conduction was observed at ∼5 nm thick film but was still much higher than for carbon substrates. These results indicate that the number of active proton-conductive pathways and/or the connectivity of the proton path network changed with film thickness. The surface morphology of thinner films was significantly affected by the film/substrate interface and was fundamentally different from that of the bulk thick membrane.


Assuntos
Polímeros de Fluorcarboneto/química , Prótons , Carbono/química , Técnicas Eletroquímicas , Eletrólitos/química , Polímeros de Fluorcarboneto/síntese química , Microscopia de Força Atômica , Tamanho da Partícula , Platina/química , Propriedades de Superfície
18.
Phys Chem Chem Phys ; 15(5): 1518-25, 2013 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-23238425

RESUMO

Solutions of Nafion® with an ion exchange capacity (IEC) of 0.91 meq g(-1), which are on the verge of the formation of SO(3)H nanoclusters, were spin coated on silicon (Si), glassy carbon (GC) and platinum/silicon (Pt/Si) substrates to form films of up to 256 nm thickness. Nanostructure of the films was studied using Doppler broadening of annihilation radiation (DBAR), positron annihilation lifetime (PAL), X-ray photoelectron spectroscopy (XPS), an atomic force microscope (AFM) and contact angle measurements. Contact angles as low as 10 degrees indicate that the surface of dry ultrathin Nafion® films on Si is highly hydrophilic. XPS data of 10 nm thick, ultrathin film on Si show that oxygen concentration is enhanced and the SO(3)H group concentration, in other words, IEC on the surface is much higher than other films. The S parameter measured by DBAR of an ultrathin Nafion® film on Si is much higher than that of the films on the other substrates. We consider that a large number of hydrophilic, reversed micelle like SO(3)H groups are on the surface of the ultrathin Nafion® film on Si but not on the surface of other films. Positrons implanted into the film are trapped by the SO(3)H clusters, annihilating with the electrons of oxygen and exhibit the high S parameter. The SO(3)H concentration on the surface of thin Nafion® films on GC and Pt/Si substrates may not be so high as the threshold for the formation of a large number of SO(3)H clusters. Positrons implanted into the films annihilate mostly with fluorine atoms, resulting in a low S parameter. The film-substrate interaction plays an essential role in nanostructuring of Nafion® thin films, which may also be the case for Nafion® on the catalysts of polymer electrolyte fuel cells.

19.
Mol Cell Proteomics ; 10(8): M110.005686, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21474797

RESUMO

Urinary proteins have been implicated as inhibitors of kidney stone formation (urolithiasis). As a proximal fluid, prefiltered by the kidneys, urine is an attractive biofluid for proteomic analysis in urologic conditions. However, it is necessary to correct for variations in urinary concentration. In our study, individual urine samples were normalized for this variation by using a total protein to creatinine ratio. Pooled urine samples were compared in two independent experiments. Differences between the urinary proteome of stone formers and nonstone-forming controls were characterized and quantified using label-free nano-ultraperformance liquid chromatography high/low collision energy switching analysis. There were 1063 proteins identified, of which 367 were unique to the stone former groups, 408 proteins were unique to the control pools, and 288 proteins were identified for comparative quantification. Proteins found to be unique in stone-formers were involved in carbohydrate metabolism pathways and associated with disease states. Thirty-four proteins demonstrated a consistent >twofold change between stone formers and controls. For ceruloplasmin, one of the proteins was shown to be more than twofold up-regulated in the stone-former pools, this observation was validated in individuals by enzyme-linked immunosorbent assay. Moreover, in vitro crystallization assays demonstrated ceruloplasmin had a dose-dependent increase on calcium oxalate crystal formation. Taken together, these results may suggest a functional role for ceruloplasmin in urolithiasis.


Assuntos
Ceruloplasmina/urina , Proteinúria/urina , Proteoma/metabolismo , Urolitíase/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Amidoidrolases/urina , Sequência de Aminoácidos , Biomarcadores/metabolismo , Biomarcadores/urina , Oxalato de Cálcio/química , Estudos de Casos e Controles , Ceruloplasmina/química , Cristalização , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/química , Proteinúria/metabolismo , Proteoma/química , Proteômica , Espectrometria de Massas em Tandem , Urolitíase/metabolismo , Adulto Jovem
20.
Sci Rep ; 13(1): 6435, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081088

RESUMO

The preparation of adsorbents plays a vital role in the adsorption method. In particular, many adsorbents with high specific surface areas and unique shapes are essential for the adsorption strategy. A Zn-Mg-Al/layer double hydroxide (LDH) was designed in this study using a simple co-precipitation process. Adsorbent based on Zn-Mg-Al/LDH was used to remove crystal violet (CV) from the wastewater. The impacts of the initial dye concentration, pH, and temperature on CV adsorption performance were systematically examined. The adsorbents were analyzed both before and after adsorption using FTIR, XRD, and SEM. The roughness parameters and surface morphologies of the produced LDH were estimated using 3D SEM images. Under the best conditions (dose of adsorbent = 0.07 g and pH = 9), the maximum adsorption capacity has been achieved. Adsorption kinetics studies revealed that the reaction that led to the adsorption of CV dye onto Zn-Mg-Al/LDH was a pseudo-second-order model. Additionally, intraparticle diffusion suggests that Zn-Mg-Al/LDH has a fast diffusion constant for CV molecules (0.251 mg/(g min1/2)). Furthermore, as predicted by the Langmuir model, the maximal Zn-Mg-Al/LDH adsorption capacity of CV was 64.80 mg/g. The CV dimensionless separation factor (RL) onto Zn-Mg-Al/LDH was 0.769, indicating that adsorption was favorable. The effect of temperature was performed at 25, 35, and 45 °C in order to establish the thermodynamic parameters ∆Ho, ∆So, and ∆Go. The computed values indicated exothermic and spontaneous adsorption processes. The study presented here might be used to develop new adsorbents with enhanced adsorption capabilities for the purpose of protecting the water environment.

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