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1.
Molecules ; 27(9)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35566066

RESUMO

This study aimed to determine the chemical composition of different types of tissue of Cedrus brevifolia Henry (Pinaceae) methanolic extracts, namely needles, twigs, branches, and bark. Cedrus brevifolia is a narrow endemic coniferous tree species of Cyprus, growing in a sole population in the mountainous area of Paphos Forest. Chemical analysis of the extracts was performed using liquid chromatography combined with time-of-flight high-resolution mass spectrometry (LC/Q-TOF/HRMS). The majority of the 36 compounds tentatively identified belonged to the flavonoids family. The extract of needles was the richest extract in terms of secondary metabolites. The extracts were studied for their antioxidant activity using the DPPH free radical scavenging assay. Additionally, the antibacterial activity was evaluated by determining both the minimum inhibitory concentration and the minimum bactericidal concentration against Staphylococcus aureus and Escherichia coli. All extracts demonstrated antioxidant property, while bark gave the highest antioxidant capacity (IC50 value of 0.011 mg/mL) compared to the other tissues. Antibacterial activity was observed against both types of bacteria, with the extract of branches presenting the strongest activity against S. aureus (MIC, 0.097 mg/mL and MBC, 0.195 mg/mL). This is the first time that extracts of needles, twigs, branches, and bark of C. brevifolia are compared regarding their chemical composition as well as their antimicrobial and antioxidant properties.


Assuntos
Anti-Infecciosos , Antioxidantes , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Cedrus , Escherichia coli , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Staphylococcus aureus
2.
Molecules ; 27(18)2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36144548

RESUMO

The purpose of this study was to identify the chemical components in root extracts of Saponaria cypria, an endemic species of Cyprus. Subsequently, the synergistic bioactivity of its root extracts through different extraction procedures was also investigated for the first time. A total of nine saponins, along with six phenolic compounds, were identified and quantified using the UHPLC/Q-TOF-MS method. Additionally, S. cypria root extracts demonstrated antibacterial potential against Escherichia coli, Staphylococcus aureus, Enterococcus faecalis and Salmonella enteritidis. S. aureus presented the highest susceptibility among all bacteria tested. These findings provide the first phytochemical data regarding the saponin, phenolic content and antimicrobial activity of S. cypria extracts, indicating that the Cyprus saponaria species is a rich natural source for bioactive compounds with a potentially wider bioactivity spectrum.


Assuntos
Saponaria , Saponinas , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , Fenóis/farmacologia , Compostos Fitoquímicos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Saponaria/química , Saponinas/farmacologia , Staphylococcus aureus
3.
Molecules ; 25(1)2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31861583

RESUMO

Inflammation and oxidative stress are involved in cardiovascular diseases. Nitrogen monoxide participates in the regulation of endothelial processes. Thus, derivatives of classic nonsteroidal anti-inflammatory drugs (NSAIDs), trolox or cinnamic acids esterified with 2-(nitrooxy)ethanol were designed and studied. It was found that the nitrogen monoxide (NO) releasing activity was comparable to that of S-nitroso-N-acetylpenicillamine. The nitrooxy derivatives decreased potently lipid indices in the plasma of hyperlipidaemic rats (30-85%). All compounds presented increased anti-inflammatory activity in vivo, inhibiting carrageenan-induced rat paw oedema as high as 76%, up to six times higher than that of the parent acids. Lipoxygenase inhibitory activity was significant for most of them, although the parent molecules exerted a minor effect (IC50 > 0.2 mM). Those compounds incorporating an antioxidant structure inhibited rat microsomal membrane lipid peroxidation strongly and possessed radical scavenging activity. These results indicated that the described compounds could act at different targets in multifactorial diseases, further limiting the possible adverse effects of drug combinations.


Assuntos
Anti-Inflamatórios/síntese química , Antioxidantes/síntese química , Cromanos/química , Cinamatos/química , Inflamação/tratamento farmacológico , Doadores de Óxido Nítrico/síntese química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Carragenina/efeitos adversos , Modelos Animais de Doenças , Esterificação , Inflamação/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Lipoxigenase/genética , Estrutura Molecular , Doadores de Óxido Nítrico/química , Doadores de Óxido Nítrico/farmacologia , Ratos
4.
Molecules ; 22(2)2017 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-28218677

RESUMO

Stress can be defined as the homeostatic, nonspecific defensive response of the organism to challenges. It is expressed by morphological, biochemical, and functional changes. In this review, we present biological and oxidative stress, as well as their interrelation. In addition to the mediation in biologic stress (central nervous, immune, and hormonal systems) and oxidative stress, the effect of these phenomena on xenobiotic metabolism and drug response is also examined. It is concluded that stress decreases drug response, a result which seems to be mainly attributed to the induction of hepatic drug metabolizing enzymes. A number of mechanisms are presented. Structure-activity studies are also discussed. Vitamin E, as well as two synthetic novel compounds, seem to reduce both oxidative and biological stress and, consequently, influence drug response and metabolism.


Assuntos
Resistência a Medicamentos , Estresse Oxidativo , Estresse Fisiológico , Animais , Antioxidantes/metabolismo , Humanos , Especificidade de Órgãos , Oxidantes/metabolismo , Oxirredução , Esteroides/metabolismo , Esteroides/farmacologia , Relação Estrutura-Atividade , Xenobióticos/química , Xenobióticos/metabolismo , Xenobióticos/farmacologia
5.
Macromolecules ; 55(3): 914-927, 2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35177871

RESUMO

The correlation function for the exit of poloxamer copolymers from equilibrated micelles is found to show up to four regimes depending on the chain flexibility: an initial fast reorganization, a logarithmic intermediate regime, followed by an exponential intermediate regime, and a final exponential decay. The logarithmic intermediate regime has been observed experimentally and attributed to the polydispersity of the polymer samples. However, we present dynamic single-chain mean-field theory simulations with chains of variable flexibility which show the same logarithmic relaxation but with strictly monodisperse systems. In agreement with our previous studies, we propose that this logarithmic response arises from a degeneracy of energy states of the hydrophobic block in the micelle core. For this to occur, a sufficiently large number of degenerate conformational states are required, which depend on the polymer flexibility and therefore should not be present for rigid polymers. Experimental results for monodisperse polymeric samples claiming the absence of such a logarithmic response may also lack a sufficient number of hydrophobic blocks for the required number of configurational states for this type of response to be seen. The insight gained from analyzing the simulation results allows us to propose a modified Eyring equation capable of reproducing the observed dynamic behavior. On scaling experimental results from different sources and systems according to this equation, we find a unique master curve showing a universal nature of the intermediate regimes: the logarithmic regime together with the secondary exponential decay. The terminal exponential regime at long times proposed by the standard Halperin and Alexander model is beyond the range of the data analyzed in this article. The universality observed suggests an entropic origin of the short-time dynamic response of this class of systems rather than the polydispersity.

6.
PLoS One ; 17(9): e0274014, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36084119

RESUMO

PURPOSE: To investigate the accuracy of surface-based ultrasound-derived PSA-density (US-PSAD) versus gold-standard MRI-PSAD as a risk-stratification tool. METHODS: Single-centre prospective study of patients undergoing MRI for suspected prostate cancer (PCa). Four combinations of US-volumes were calculated using transperineal (TP) and transabdominal (TA) views, with triplanar measurements to calculate volume and US-PSAD. Intra-class correlation coefficient (ICC) was used to compare US and MRI volumes. Categorical comparison of MRI-PSAD and US-PSAD was performed at PSAD cut-offs <0.15, 0.15-0.20, and >0.20 ng/mL2 to assess agreement with MRI-PSAD risk-stratification decisions. RESULTS: 64 men were investigated, mean age 69 years and PSA 7.0 ng/mL. 36/64 had biopsy-confirmed prostate cancer (18 Gleason 3+3, 18 Gleason ≥3+4). Mean MRI-derived gland volume was 60 mL, compared to 56 mL for TA-US, and 65 mL TP-US. ICC demonstrated good agreement for all US volumes with MRI, with highest agreement for transabdominal US, followed by combined TA/TP volumes. Risk-stratification decisions to biopsy showed concordant agreement between triplanar MRI-PSAD and ultrasound-PSAD in 86-91% and 92-95% at PSAD thresholds of >0.15 ng/mL2 and >0.12 ng/mL2, respectively. Decision to biopsy at threshold >0.12 ng/mL2, demonstrated sensitivity ranges of 81-100%, specificity 85-100%, PPV 86-100% and NPV 83-100%. Transabdominal US provided optimal sensitivity of 100% for this clinical decision, with specificity 85%, and transperineal US provided optimal specificity of 100%, with sensitivity 87%. CONCLUSION: Transperineal-US and combined TA-TP US-derived PSA density values compare well with standard MRI-derived values and could be used to provide accurate PSAD at presentation and inform the need for further investigations.


Assuntos
Antígeno Prostático Específico , Neoplasias da Próstata , Idoso , Estudos de Viabilidade , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Prospectivos , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Estudos Retrospectivos
7.
Int J Mol Med ; 49(1)2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34821371

RESUMO

Severe early­onset obesity is mainly attributed to single gene variations of the hypothalamic leptin­melanocortin system, which is critical for controlling the balance between appetite and energy expenditure. Adenylate cyclase 3 (ADCY3), a transmembrane enzyme localized in primary neuronal cilia, is a key genetic candidate, which appears to have an essential role in regulating body weight. The present study aimed to identify ADCY3 genetic variants in severely obese young patients of Greek­Cypriot origin by genomic sequencing. Apart from previously reported variants, the novel and probably pathogenic variant c.349T>A, causing a p.Leu117Met substitution within one of the two pseudo­symmetric halves of the transmembrane part of the protein, was reported. Molecular modelling analysis used to delineate bonding interactions within the mutated protein structure strongly suggested a change in interactive forces and energy levels affecting the pseudo­twofold symmetry of the transmembrane domain of the protein and probably its catalytic function. These results support the involvement of ADCY3 in the pathology of the disease and point towards the requirement of defining protein function and evaluating the clinical significance of the detected variants.


Assuntos
Adenilil Ciclases/química , Adenilil Ciclases/genética , Variação Genética , Obesidade/genética , Adolescente , Substituição de Aminoácidos , Chipre , Feminino , Humanos , Masculino , Modelos Moleculares , Adulto Jovem
8.
Front Public Health ; 9: 758030, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869173

RESUMO

University students represent a highly active group in terms of their social activity in the community and in the propagation of information on social media. We aimed to map the knowledge, attitudes, and perceptions of University students in Cyprus about severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and Coronavirus disease 2019 (COVID-19) to guide targeted future measures and information campaigns. We used a cross-sectional online survey targeting all students in conventional, not distance-learning, programs in five major universities in the Republic of Cyprus. Students were invited to participate through the respective Studies and Student Welfare Office of each institution. The survey was made available in English and Greek on REDCap. Participation was voluntary and anonymous. The questionnaire was developed based on a consensus to cover the main factual information directed by official channels toward the general public in Cyprus at the time of the survey. In addition to sociodemographic information (N = 8), the self-administered questionnaire consisted of 19 questions, assessing the knowledge regarding the characteristics of SARS-CoV-2 and COVID-19, infection prevention and control measures (N = 10), perceptions related to COVID-19, for instance, whether strict travel measures are necessary (N = 4), and attitudes toward a hypothetical person infected (N = 2). Furthermore, participants were asked to provide their own assessment of their knowledge about COVID-19 and specifically with regard to the main symptoms and ways of transmission (N = 3). The number of students who completed the survey was 3,641 (41% studying Health/Life Sciences). Amongst them, 68.8% responded correctly to at least 60% of knowledge-related questions. Misconceptions were identified in 30%. Only 29.1% expressed a positive attitude toward a hypothetical person with COVID-19 without projecting judgment (9.2%) or blame (38%). Odds of expressing a positive attitude increased by 18% (95% CI 13-24%; p < 0.001) per unit increase in knowledge. Postgraduate level education was predictive of better knowledge (odds ratio (OR) 1.81; 95% CI 1.34-2.46; p < 0.001 among doctoral students] and positive attitude [OR 1.35; 95% CI 1.01-1.80; p = 0.04). In this study, we show that specific knowledge gaps and misconceptions exist among University students about SARS-CoV-2 and COVID-19 and their prevalence is associated with negative attitudes toward people with COVID-19. Our findings highlight the integrated nature of knowledge and attitude and suggest that improvements to the former could contribute to improvements in the latter.


Assuntos
COVID-19 , Atitude , Estudos Transversais , Chipre , Humanos , SARS-CoV-2 , Estudantes , Universidades
9.
Eur Urol Focus ; 6(1): 95-101, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31928632

RESUMO

BACKGROUND: Sepsis is a severe complication following transrectal ultrasound-guided prostate biopsy (TRUSPBx). Ciprofloxacin is commonly used for prophylaxis; however, there is an increasing incidence of resistant enteric organisms worldwide. OBJECTIVE: To investigate the effect of a targeted prophylactic antimicrobial regimen based on rectal swab cultures in reducing the rate of sepsis. DESIGN, SETTING, AND PARTICIPANTS: A total of 1012 patients were included. Group A (609 patients) received an empirical prophylactic antimicrobial regimen of gentamicin, metronidazole, and ciprofloxacin. Targeted antimicrobial prophylaxis was introduced due to significant ciprofloxacin and gentamicin resistance in patients admitted with sepsis following TRUSPBx. The remaining 403 patients (Group B) had rectal swab cultures performed prior to biopsy. Patients with organisms resistant to ciprofloxacin or gentamicin received a targeted prophylaxis regimen of fosfomycin, amikacin, and metronidazole. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We retrospectively collected and analysed data on sepsis and bacteraemia for all patients as well as data on rectal swab culture, recent foreign travel, and recent antibiotic use for patients in Group B. RESULTS AND LIMITATIONS: In group A, 12 (2.0%) patients developed sepsis following TRUSPBx, while in group B, 9 (2.2%) patients developed sepsis despite targeted prophylaxis (p=0.82). Patients with ciprofloxacin-resistant rectal flora had a significantly higher rate of sepsis (9.1% vs 1.1%; p=0.003). There was a reduction in patients admitted with bacteraemia and severe sepsis between group A (1.2%) and group B (0.3%) which did not reach statistical significance (p=0.16). In group B, 55 of 403 (13.6%) patients had ciprofloxacin-resistant rectal flora, while 66 (16.4%) had organisms resistant to both ciprofloxacin and gentamicin. A recent foreign travel history was associated with an increased incidence of ciprofloxacin-resistant rectal flora (23.6% vs 10.8%; p=0.007). The main limitations of our study include its retrospective nature and potential under-reporting of less severe infectious complications. CONCLUSIONS: Rectal swab cultures identify patients with ciprofloxacin-resistant rectal flora who have an eight-fold risk of sepsis. Targeted antimicrobial prophylaxis may not be beneficial in reducing the sepsis rate when compared with augmented empirical prophylaxis. In an era of increasing antimicrobial resistance, transperineal prostate biopsies should be considered to reduce the risk of infective complications. PATIENT SUMMARY: Performing rectal swab culture prior to transrectal prostate biopsy can help identify patients at risk of developing sepsis despite targeted prophylactic antibiotics.


Assuntos
Antibacterianos/uso terapêutico , Antibioticoprofilaxia/métodos , Ciprofloxacina/uso terapêutico , Gentamicinas/uso terapêutico , Metronidazol/uso terapêutico , Complicações Pós-Operatórias/microbiologia , Complicações Pós-Operatórias/prevenção & controle , Próstata/patologia , Reto/microbiologia , Sepse/prevenção & controle , Técnicas Bacteriológicas , Biópsia/métodos , Humanos , Masculino , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Medição de Risco , Sepse/epidemiologia
10.
Br J Radiol ; 93(1112): 20200298, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32479105

RESUMO

OBJECTIVE: To compare the performance of Likert and Prostate Imaging-Reporting and Data System (PI-RADS) multiparametric (mp) MRI scoring systems for detecting clinically significant prostate cancer (csPCa). METHODS: 199 biopsy-naïve males undergoing prostate mpMRI were prospectively scored with Likert and PI-RADS systems by four experienced radiologists. A binary cut-off (threshold score ≥3) was used to analyze histological results by three groups: negative, insignificant disease (Gleason 3 + 3; iPCa), and csPCa (Gleason ≥3 +4). Lesion-level results and prostate zonal location were also compared. RESULTS: 129/199 (64.8%) males underwent biopsy, 96 with Likert or PI-RADS score ≥3, and 21 with negative MRI. A further 12 patients were biopsied during follow-up (mean 507 days). Prostate cancer was diagnosed in 87/199 (43.7%) patients, 65 with (33.6%) csPCa. 30/92 (32.6%) patients with negative MRI were biopsied, with an NPV of 83.3% for cancer and 86.7% for csPCa. Likert and PI-RADS score differences were observed in 92 patients (46.2%), but only for 16 patients (8%) at threshold score ≥3. Likert scoring had higher specificity than PI-RADS (0.77 vs 0.66), higher area under the curve (0.92 vs 0.87, p = 0.002) and higher PPV (0.66 vs 0.58); NPV and sensitivity were the same. Likert had more five score results (58%) compared to PI-RADS (36%), but with similar csCPa detection (81.0 and 80.6% respectively). Likert demonstrated lower proportion of false positive in the predominately AFMS-involving lesions. CONCLUSION: Likert and PI-RADS systems both demonstrate high cancer detection rates. Likert scoring had a higher AUC with moderately higher specificity and lower positive call rate and could potentially help to reduce the number of unnecessary biopsies performed. ADVANCES IN KNOWLEDGE: This paper illustrates that the Likert scoring system has potential to help urologists reduce the number of prostate biopsies performed.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias da Próstata/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Curr Top Med Chem ; 19(4): 276-291, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30706817

RESUMO

BACKGROUND: The biotransformation of xenobiotics is a homeostatic defensive response of the body against bioactive invaders. Xenobiotic metabolizing enzymes, important for the metabolism, elimination and detoxification of exogenous agents, are found in most tissues and organs and are distinguished into phase I and phase II enzymes, as well as phase III transporters. The cytochrome P450 superfamily of enzymes plays a major role in the biotransformation of most xenobiotics as well as in the metabolism of important endogenous substrates such as steroids and fatty acids. The activity and the potential toxicity of numerous drugs are strongly influenced by their biotransformation, mainly accomplished by the cytochrome P450 enzymes, one of the most versatile enzyme systems. OBJECTIVE: In this review, considering the importance of drug metabolising enzymes in health and disease, some of our previous research results are presented, which, combined with newer findings, may assist in the elucidation of xenobiotic metabolism and in the development of more efficient drugs. CONCLUSION: Study of drug metabolism is of major importance for the development of drugs and provides insight into the control of human health. This review is an effort towards this direction and may find useful applications in related medical interventions or help in the development of more efficient drugs.


Assuntos
Inibidores das Enzimas do Citocromo P-450/farmacologia , Sistema Enzimático do Citocromo P-450/metabolismo , Desenho de Fármacos , Xenobióticos/metabolismo , Biotransformação/efeitos dos fármacos , Inibidores das Enzimas do Citocromo P-450/química , Inibidores das Enzimas do Citocromo P-450/metabolismo , Interações Medicamentosas , Humanos , Xenobióticos/química
12.
BMC Genomics ; 8: 26, 2007 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-17244347

RESUMO

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a fatal disorder caused by the progressive degeneration of motoneurons in brain and spinal cord. Despite identification of disease-linked mutations, the diversity of processes involved and the ambiguity of their relative importance in ALS pathogenesis still represent a major impediment to disease models as a basis for effective therapies. Moreover, the human motor cortex, although critical to ALS pathology and physiologically altered in most forms of the disease, has not been screened systematically for therapeutic targets. RESULTS: By whole-genome expression profiling and stringent significance tests we identify genes and gene groups de-regulated in the motor cortex of patients with sporadic ALS, and interpret the role of individual candidate genes in a framework of differentially expressed pathways. Our findings emphasize the importance of defense responses and cytoskeletal, mitochondrial and proteasomal dysfunction, reflect reduced neuronal maintenance and vesicle trafficking, and implicate impaired ion homeostasis and glycolysis in ALS pathogenesis. Additionally, we compared our dataset with publicly available data for the SALS spinal cord, and show a high correlation of changes linked to the diseased state in the SALS motor cortex. In an analogous comparison with data for the Alzheimer's disease hippocampus we demonstrate a low correlation of global changes and a moderate correlation for changes specifically linked to the SALS diseased state. CONCLUSION: Gene and sample numbers investigated allow pathway- and gene-based analyses by established error-correction methods, drawing a molecular portrait of the ALS motor cortex that faithfully represents many known disease features and uncovers several novel aspects of ALS pathology. Contrary to expectations for a tissue under oxidative stress, nuclear-encoded mitochondrial genes are uniformly down-regulated. Moreover, the down-regulation of mitochondrial and glycolytic genes implies a combined reduction of mitochondrial and cytoplasmic energy supply, with a possible role in the death of ALS motoneurons. Identifying candidate genes exclusively expressed in non-neuronal cells, we also highlight the importance of these cells in disease development in the motor cortex. Notably, some pathways and candidate genes identified by this study are direct or indirect targets of medication already applied to unrelated illnesses and point the way towards the rapid development of effective symptomatic ALS therapies.


Assuntos
Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Perfilação da Expressão Gênica , Córtex Motor/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Feminino , Hipocampo/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Medula Espinal/metabolismo
13.
J Genet ; 96(1): 155-160, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28360400

RESUMO

The prevalence of genetic variants associated to cutaneous melanoma (CM) has never been determined within Cypriot melanomas. This study evaluates the frequency of variants in cyclin-dependent kinase inhibitor 2A (CDKN2A) and melanocortin-1 receptor (MC1R) in 32 patients diagnosed with CM. Other characteristics and risk factors were also assessed. CDKN2A p.Ala148Thr was detected in three of 32 patients, while the control group revealed no variations within CDKN2A. MC1R screening in 32 patients revealed the following variations: p.Val60Leu in 11 patients, p.Arg142His in four patients, p.Thr314Thr in one patient, p.Arg160Trp in one patient, p.Val92Met/p.Thr314Thr in one patient and p.Val92Met/p.Arg142His/p.Thr314Thr in one patient. The control group revealed only p.Val60Leu (in 10 of 45 individuals), which is frequently found in general populations. Two unrelated patients carried CDKN2A p.Ala148Thr in combination with MC1R p.Arg142His, suggesting digenic inheritance that may provide evidence of different gene variants acting synergistically to contribute for CM development. This study confirms the presence of CDKN2A and MC1R variants among Cypriot melanomas and supports existing evidence of a role for these variants in susceptibility to melanoma.


Assuntos
Inibidor p16 de Quinase Dependente de Ciclina/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Melanoma/diagnóstico , Melanoma/genética , Receptor Tipo 1 de Melanocortina/genética , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/genética , Adulto , Idoso , Alelos , Substituição de Aminoácidos , Feminino , Genótipo , Grécia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Melanoma Maligno Cutâneo
14.
Cardiovasc Intervent Radiol ; 39(11): 1595-1603, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27435582

RESUMO

INTRODUCTION: The authors compared the oncologic outcomes of radiofrequency ablation (RFA) with robotic-assisted partial nephrectomy (RPN) for the treatment of T1 stage renal cell carcinoma (RCC). MATERIALS AND METHODS: This was a retrospective data analysis of a high-volume single tertiary centre. Patients were treated with RFA or RPN following multidisciplinary decision making. Only histologically proven RCCs were included. Baseline demographics were collected, and PADUA scores of tumour features were calculated to standardize baseline anatomy. Peri-operative complications, kidney function and oncological outcomes were compared. RESULTS: Sixty-three cases were included in each group. Baseline renal function was poorer in RFA, and 16/63 RFA patients had tumours in single kidneys compared to 1/63 RPN cases (p < 0.001). Length of stay was shorter in RFA (1 vs. 3 days, p < 0.0001). Post-procedure renal function decline at 30 days was significantly less in RFA [(-0.8) ± 9.6 vs. (-16.1) ± 19.5 mls/min/1.73 m2; p < 0.0001]. More minor complications were recorded in RPN (10/63 vs. 4/63, p = 0.15), but local recurrence was numerically higher in RFA (6/63 vs. 1/63, p = 0.11). Disease-free survival (DFS) was not significantly different (adjusted HR = 0.6, 95 % Cl 0.1-3.7; p = 0.60). Increasing tumour size was an independent predictor of local recurrence (adjusted HR = 1.7; 95 % Cl 1.1-2.6 per cm; p = 0.02). CONCLUSIONS: Both RPN and RFA offer very good oncological outcomes for the treatment of T1 RCC with low peri-operative morbidity and similar oncologic outcomes. RFA demonstrated fewer peri-operative complications and better preservation of renal function, whereas RPN had an insignificantly lower local recurrence rate. RFA should be offered alongside RPN for selected cases.


Assuntos
Ablação por Cateter/métodos , Neoplasias Renais/cirurgia , Nefrectomia/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Adulto , Idoso , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Estudos Retrospectivos , Resultado do Tratamento
15.
Hormones (Athens) ; 15(3): 445-452, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27394708

RESUMO

OBJECTIVE: Heterozygous mutations on the melanocortin-4-receptor gene (MC4R) are the most frequent cause of monogenic obesity. We describe a novel MC4R deletion in a girl with severe early onset obesity, tall stature, pale skin and red hair. CASE REPORT: Clinical and hormonal parameters were evaluated in a girl born full-term by non-consanguineous parents. Her body mass index (BMI) at presentation (3 years) was 30 kg/m2 (z-score: +4.5SDS). By the age of 5.2 years, she exhibited extreme linear growth acceleration and developed hyperinsulinemia. METHODS: Direct sequencing of the MC4R, MC1Rand for the knownFTOsingle nucleotide polymorphism (SNP) rs9939609was performed for the patient and her family. RESULTS: A novel heterozygous MC4R p.Met215del (c.643_645delATG) deletion was identified in the patient, her father and her brother, both of whom exhibited a milder phenotype. 3D structural dynamic simulation studies investigated the conformational changes induced by the p.Met215del. The patient and her mother were also found to be carriers of the obesity risk associated FTOrs9939609SNP. Finally, the identification of the known p.Arg160Trp MC1Rvariant in the patient accounts for the red hair and pale skin phenotypic features. CONCLUSION: The p.Met215del causes global conformational and functional changes as it is localized at the alpha-helical transmembrane regions and the membrane spanning regions of the beta-barrel. This novel mutation produces a severe overgrowth phenotype that is apparent as from infancy and is progressive in childhood. The additional negative effect of environmental and unhealthy lifestyle habits as well as a possible co-interaction of FTOrs9939609 SNP may worsen the phenotype.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Deleção de Genes , Obesidade Infantil/genética , Polimorfismo de Nucleotídeo Único , Receptor Tipo 1 de Melanocortina/genética , Receptor Tipo 4 de Melanocortina/genética , Idade de Início , Índice de Massa Corporal , Criança , Pré-Escolar , Comportamento Alimentar , Feminino , Predisposição Genética para Doença , Cor de Cabelo/genética , Hereditariedade , Heterozigoto , Humanos , Hiperfagia/genética , Hiperfagia/fisiopatologia , Obesidade Infantil/diagnóstico , Obesidade Infantil/fisiopatologia , Linhagem , Fenótipo , Conformação Proteica , Receptor Tipo 4 de Melanocortina/química , Receptor Tipo 4 de Melanocortina/metabolismo , Índice de Gravidade de Doença , Pigmentação da Pele/genética , Relação Estrutura-Atividade
16.
Inflamm Bowel Dis ; 21(12): 2839-47, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26296064

RESUMO

BACKGROUND: Crohn's disease (CD) is a risk factor for vitamin B12 deficiency due to frequent involvement of the terminal ileum. Conventional screening for B12 deficiency with serum B12 is relatively insensitive and measures total B12 concentration, of which a minority is present in a biologically active form. Holotranscobalamin (holoTC) combined with methylmalonic acid (MMA) is believed to be more accurate in identifying impaired B12 status. We evaluated the prevalence and risk factors for B12 deficiency using holoTC supported by MMA among patients with CD. METHODS: We performed a single-center service evaluation of 381 patients with CD who underwent B12 assessment (holoTC/MMA) and compared them with 141 patients with ulcerative colitis. Eighty-nine patients with CD underwent paired serum B12 and holoTC. Among patients with CD, risk factors including terminal ileal resection length, ileal inflammation on endoscopy, and disease characteristics on magnetic resonance imaging were recorded. RESULTS: Prevalence of B12 deficiency among patients with CD was 33% compared with 16% in ulcerative colitis (P < 0.0001). In 89 patients who underwent paired tests, conventional testing identified B12 deficiency in 5% of patients with CD, which increased to 32% using holoTC/MMA. Independent risk factors for B12 deficiency were ileal resection length ≤20 cm (odds ratio: 3.0, 95% confidence interval, 1.5-6.0, P = 0.002) and >20 cm (odds ratio: 6.7, 95% confidence interval, 3.0-14.7, P < 0.0001) and ileal inflammation (odds ratio: 3.9, 95% confidence interval, 2.2-6.9, P < 0.0001). On magnetic resonance imaging, active terminal ileal inflammation (P = 0.02) and an increased disease burden (≥1 skip lesion, P = 0.01 and prestenotic dilatation >3 cm, P = 0.01) were associated with B12 deficiency. CONCLUSIONS: Vitamin B12 deficiency is common in patients with CD. holoTC supported by MMA identifies patients with B12 deficiency considered replete on conventional testing.


Assuntos
Doença de Crohn/complicações , Deficiência de Vitamina B 12/diagnóstico , Vitamina B 12/sangue , Adulto , Biomarcadores/sangue , Colite Ulcerativa/sangue , Colite Ulcerativa/complicações , Doença de Crohn/sangue , Feminino , Humanos , Íleo/patologia , Masculino , Ácido Metilmalônico/sangue , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Transcobalaminas/análise , Deficiência de Vitamina B 12/sangue , Deficiência de Vitamina B 12/epidemiologia , Deficiência de Vitamina B 12/etiologia
17.
J Med Biogr ; 22(3): 180-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24944050

RESUMO

In spite of his contribution to psychiatry in 19th century Britain, Henry Maudsley remains a mysterious figure, a man mostly known for his donation to the London County Council for the building of the Maudsley Hospital and for The Maudsley Annual Lecture created in honour of his benevolence. Besides Sir Aubrey Lewis' article in 1951 and Michael Collie's attempt in 1988 to construct a biographical study on Maudsley, there does not seem to be any current endeavour to tell the story of his life, whereas Trevor Turner's contribution to the 2004 Oxford Dictionary of National Biography gives a somewhat scathing but unattributed account of Maudsley's personality. This essay attempts to explore his contributions to the Medico-Psychological Association (MPA), the current Royal College of Psychiatrists, his editorship of the Journal of Mental Health (currently named the British Journal of Psychiatry), his literary contributions and his vision for a psychiatric hospital. This essay is an attempt to demystify his figure and to explore some of the rumours and criticisms surrounding his name and the reasons why so little has been written about him. It is also a venture to unravel his complex personality and his intricate philosophy.


Assuntos
Hospitais Psiquiátricos/história , Psiquiatria/história , Feminino , História do Século XIX , História do Século XX , Humanos , Masculino , Masturbação/história , Masturbação/psicologia , Sociedades Médicas/história , Reino Unido
18.
Neurobiol Dis ; 26(3): 577-89, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17418584

RESUMO

The molecular mechanisms underlying the selective neurodegeneration of motor neurons in amyotrophic lateral sclerosis (ALS) are inadequately understood. Recent breakthroughs have implicated impaired axonal transport, mediated by molecular motors, as a key element for disease onset and progression. The current work identifies the expression of 15 kinesin-like motors in healthy human motor cortex, including three novel isoforms. Our comprehensive quantitative mRNA analysis in control and sporadic ALS (SALS) motor cortex specimens detects SALS-specific down-regulation of KIF1Bbeta and novel KIF3Abeta, two isoforms we show to be enriched in the brain, and also of SOD1, a key enzyme linked to familial ALS. This is accompanied by a marked reduction of KIF3Abeta protein levels. In the motor cortex KIF3Abeta localizes in cholinergic neurons, including upper motor neurons. No mutations causing splicing defects or altering protein-coding sequences were identified in the genes of the three proteins. The present study implicates two motor proteins as possible candidates in SALS pathology.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Regulação da Expressão Gênica , Proteínas Motores Moleculares/metabolismo , Córtex Motor/metabolismo , Neurônios Motores/metabolismo , Idoso , Processamento Alternativo/genética , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/fisiopatologia , Animais , Fibras Colinérgicas/metabolismo , Fibras Colinérgicas/patologia , Modelos Animais de Doenças , Regulação para Baixo/genética , Feminino , Regulação da Expressão Gênica/fisiologia , Marcadores Genéticos/genética , Humanos , Cinesinas/genética , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Proteínas Motores Moleculares/genética , Córtex Motor/fisiopatologia , Neurônios Motores/patologia , Mutação/genética , Proteínas do Tecido Nervoso/genética , Isoformas de Proteínas/genética , RNA Mensageiro/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase-1
19.
Biochemistry ; 44(14): 5402-8, 2005 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-15807533

RESUMO

P700, the primary electron donor of photosystem I, is an asymmetric dimer made of one molecule of chlorophyll a' (P(A)) and one of chlorophyll a (P(B)) that are bound to the homologous PsaA and PsaB polypeptides. While the carbonyl groups of P(A) are involved in hydrogen-bonding interactions with several surrounding amino acid side chains and a water molecule, P(B) does not engage hydrogen bonds with the protein. Notably, the residue Thr A739 is donating a strong hydrogen bond to the 9-keto C=O group of P(A) and the homologous residue Tyr B718 is free from interaction with P(B). Light-induced FTIR difference spectroscopy of the photooxidation of P700 has been combined with a site-directed mutagenesis attempt to introduce hydrogen bonds to the carbonyl groups of P(B) in Synechocystis sp. PCC 6803. The FTIR study of the Y(B718)T mutant provides evidence that the 9-keto C=O group of P(B) and P(B)(+) engages a relatively strong hydrogen-bonding interaction with the surroundings in a significant fraction (40 +/-10%) of the reaction centers. Additional mutations on the two PsaB residues homologous to those involved in the main interactions between the PsaA polypeptide and the 10a-carbomethoxy groups of P(A) affect only marginally the vibrational frequency of the 10a-ester C=O group of P(B). The FTIR data on single, double, and triple mutants at these PsaB sites indicate a plasticity of the interactions of the carbonyl groups of P(B) with the surrounding protein. However, these mutations do not perturb the hydrogen-bonding interactions assumed by the 9-keto and 10a-ester C=O groups of P(A) and P(A)(+) with the protein and have only a limited effect on the relative charge distribution between P(A)(+) and P(B)(+).


Assuntos
Complexo de Proteína do Fotossistema I/química , Synechocystis/química , Ligação de Hidrogênio , Modelos Moleculares , Mutagênese Sítio-Dirigida , Complexo de Proteína do Fotossistema I/genética , Espectroscopia de Infravermelho com Transformada de Fourier
20.
Biochemistry ; 43(26): 8380-90, 2004 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-15222750

RESUMO

P700, the primary electron donor of photosystem I is an asymmetric dimer made of one molecule of chlorophyll a' (P(A)) and one of chlorophyll a (P(B)). While the carbonyl groups of P(A) are involved in hydrogen-bonding interactions with several surrounding amino acid side chains and a water molecule, P(B) does not engage in hydrogen bonding with the protein. Light-induced FTIR difference spectroscopy of the photooxidation of P700 has been combined with site-directed mutagenesis in Synechocystis sp. PCC 6803 to investigate the influence of these hydrogen bonds on the structure of P700 and P700(+). When the residue Thr A739, which donates a hydrogen bond to the 9-keto C=O group of P(A), is changed to Phe, a differential signal at 1653(+)/1638(-) cm(-1) in the P700(+)/P700 FTIR difference spectrum upshifts by approximately 30-40 cm(-1), as expected for the rupture of the hydrogen bond or, at least, a strong decrease of its strength. The same upshift is also observed in the FTIR spectrum of a triple mutant in which the residues involved in the three main hydrogen bonds to the 9-keto and 10a-carbomethoxy groups of P(A) have been changed to the symmetry-related side chains present around P(B). In addition, the spectrum of the triple mutant shows a decrease of a differential signal around 1735 cm(-1) and the appearance of a new signal around 1760 cm(-1). This is consistent with the perturbation of a bound 10a-ester C=O group that becomes free in the triple mutant. All of these observations support the assignment scheme proposed previously for the carbonyls of P700 and P700(+) [Breton, J., Nabedryk, E., and Leibl, W. (1999) Biochemistry 38, 11585-11592] and therefore reinforce our previous conclusions that the positive charge in P700(+) is largely delocalized over P(A) and P(B).


Assuntos
Proteínas de Bactérias , Proteínas de Transporte/química , Clorofila/química , Cianobactérias/metabolismo , Lipoproteínas/química , Proteínas de Membrana Transportadoras , Mutação , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Adesinas Bacterianas , Carbono/química , Divisão Celular , Ligação de Hidrogênio , Luz , Modelos Moleculares , Mutagênese Sítio-Dirigida , Nitrogênio/química , Treonina/química
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