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1.
Front Public Health ; 12: 1386721, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38962770

RESUMO

Background: Image and Performance-Enhancing Drugs (IPEDs) can enhance mental and physical capabilities and impact one's overall health. Initially confined in sport environments, IPEDs use has become increasingly widespread in a high-performing society. The present study was aimed at profiling IPEDs use during the COVID-19 lockdown among an international sample of young adults. Methods: A cross-sectional observational study was carried out in eight countries (United Kingdom, Italy, Lithuania, Hungary, Portugal, Spain, Brazil, and Japan) between April and May 2020. The survey questionnaire included validated measurements such as Exercise Addiction Inventory (EAI), Appearance Anxiety Inventory (AAI), and Self-Compassion Scale (SCS) as well as questions about the type of IPEDs, purchasing methods and socio-demographic information. Results: A total of 736 IPEDs users were included in the survey. Their mean age was 33.05 years (±SD = 10.06), and 64.2% were female participants. Overall, 6.8% were found at risk of exercise addiction (EAI >24), 27.6% presented high levels of appearance anxiety, and 24.9% revealed low levels of emotional regulation's self-compassion. Most participants (55.6%) purchased IPEDs through pharmacies/specialized shops, while 41.3% purchased IPEDs on the Internet. Online IPEDs buyers were mainly men who had higher scores on the Exercise Addiction Inventory. One or more IPEDs classifiable as "potentially risky" were used by 66.3% of the sample. Users of "potentially risky IPEDs" were younger and primarily men. They showed higher scores both on the Exercise Addiction Inventory and Appearance Anxiety Inventory. Conclusion: This study profiled users of IPEDs when the most restrictive COVID-19 lockdown policies were implemented in all the participating countries. More targeted post-COVID 19 prevention strategies should be implemented according to the emerged socio-demographic and psychopathological traits and cross-cultural differences emerged. Longitudinal studies will also be needed to determine the long-term effect of the COVID-19 lockdown on IPEDs consumption.


Assuntos
COVID-19 , Substâncias para Melhoria do Desempenho , Humanos , Masculino , COVID-19/epidemiologia , Feminino , Adulto , Estudos Transversais , Inquéritos e Questionários , Adulto Jovem , Exercício Físico , Comportamento Aditivo/psicologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , SARS-CoV-2
2.
Aten Primaria ; 56(7): 102922, 2024 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-38583414

RESUMO

The care of migrant patients includes initial screening and lifelong monitoring, highlighting the importance of preventing and tracking chronic, communicable and non-communicable diseases. The prevalence of hypertension, diabetes mellitus, dyslipidemia, and obesity varies by ethnicity, influenced by genetic factors, lifestyle, and socio-economic status. Preventive measures, health promotion, and risk factor identification are crucial. Chronic communicable diseases may manifest years after transmission, underscoring the necessity of primary care screening, especially for populations from endemic or high-risk areas. Imported skin lesions are a common reason for consultation among migrant and traveller patients. Their ethiology is varied, ranging from common conditions such as scabies, mycoses, and urticaria to tropical dermatoses like filariasis and leprosy.


Assuntos
Dermatopatias , Migrantes , Humanos , Doença Crônica , Dermatopatias/etiologia , Doenças não Transmissíveis/epidemiologia , Doenças Transmissíveis/epidemiologia
3.
Seizure ; 113: 54-57, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37976802

RESUMO

PURPOSE: to determine the yield of Video-Electroencephalogram (VEEG) in the first 24 h in patients with a first unprovoked seizure and normal neurological examination, laboratory findings, and cranial CT scans. METHODS: we analyzed retrospectively the yield of VEEG performed in these patients in the emergency department. All the patients were subsequently seen in the Epilepsy Clinic, and the epilepsy diagnosis was confirmed. RESULTS: we included 19 patients who met the inclusion criteria; all of them underwent VEEG with the 10-20 system within the first 24 h after the seizure. The duration of the recordings averaged at 108.53 min and may or may not have included intermittent photic stimulation and sleep recording; 74% of the recordings were abnormal, with 26% being normal. Among the abnormal cases, epileptogenic activity was found in 47% and seizures in 26% of the patients; because both findings could be present in the same VEEG, 63% of all the VEEG showed epileptogenic alterations or seizures. The VEEG anomalies were recorded before the 20th minute (standard VEEG duration) in 58% of patients who exhibited epileptogenic activity and/or seizures, and after the 20th minute in 42%. CONCLUSION: conducting approximately 100-minute VEEGs within the first 24 h after a first unprovoked seizure can enhance the diagnostic yield in patients with epilepsy. However, the study has the limitations of its sample size and retrospective nature.


Assuntos
Epilepsia , Convulsões , Humanos , Estudos Retrospectivos , Convulsões/diagnóstico por imagem , Epilepsia/diagnóstico por imagem , Eletroencefalografia , Tomografia Computadorizada por Raios X
4.
Phys Rev E ; 106(2-1): 024402, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36109976

RESUMO

We analyze the dynamical mechanisms underlying the formation of arrhythmogenic early afterdepolarizations (EADs) in two mathematical models of cardiac cellular electrophysiology: the Sato et al. biophysically detailed model of a rabbit ventricular myocyte of dimension 27 and a reduced version of the Luo-Rudy mammalian myocyte model of dimension 3. Based on a comparison of the two models, with detailed bifurcation analysis using spike-counting techniques and continuation methods in the simple model and numerical explorations in the complex model, we locate the point where the first EAD originates in an unstable branch of periodic orbits. These results serve as a basis to propose a conjectured scheme involving a hysteresis mechanism with the creation of alternans and EADs in the unstable branch. This theoretical scheme fits well with electrophysiological experimental data on EAD generation and hysteresis phenomena. Our findings open the door to the development of novel methods for pro-arrhythmia risk prediction related to EAD generation without actual induction of EADs.


Assuntos
Modelos Cardiovasculares , Miócitos Cardíacos , Potenciais de Ação/fisiologia , Animais , Arritmias Cardíacas , Simulação por Computador , Mamíferos , Miócitos Cardíacos/fisiologia , Coelhos
5.
Chaos ; 31(7): 073137, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34340346

RESUMO

Arrhythmogenic early afterdepolarizations (EADs) are investigated in a biophysically detailed mathematical model of a rabbit ventricular myocyte, providing their location in the parameter phase space and describing their dynamical mechanisms. Simulations using the Sato model, defined by 27 state variables and 177 parameters, are conducted to generate electrical action potentials (APs) for different values of the pacing cycle length and other parameters related to sodium and calcium concentrations. A detailed study of the different AP patterns with or without EADs is carried out, showing the presence of a high variety of temporal AP configurations with chaotic and quasiperiodic behaviors. Regions of bistability are identified and, importantly, linked to transitions between different behaviors. Using sweeping techniques, one-, two-, and three-parameter phase spaces are provided, allowing ascertainment of the role of the selected parameters as well as location of the transition regions. A Devil's staircase, with symbolic sequence analysis, is proposed to describe transitions in the ratio between the number of voltage (EAD and AP) peaks and the number of APs. To conclude, the obtained results are linked to recent studies for low-dimensional models and a conjecture is made for the internal dynamical structure of the transition region from non-EAD to EAD behavior using fold and cusp bifurcations and maximal canards.


Assuntos
Modelos Cardiovasculares , Miócitos Cardíacos , Potenciais de Ação , Animais , Arritmias Cardíacas , Cálcio , Coelhos
6.
Chaos ; 31(4): 043108, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34251255

RESUMO

Bursting phenomena and, in particular, square-wave or fold/hom bursting, are found in a wide variety of mathematical neuron models. These systems have different behavior regimes depending on the parameters, whether spiking, bursting, or chaotic. We study the topological structure of chaotic invariant sets present in square-wave bursting neuron models, first detailed using the Hindmarsh-Rose neuron model and later exemplary in the more realistic model of a leech heart neuron. We show that the unstable periodic orbits that form the skeleton of the chaotic invariant sets are deeply related to the spike-adding phenomena, typical from these models, and how there are specific symbolic sequences and a symbolic grammar that organize how and where the periodic orbits appear. Linking this information with the topological template analysis permits us to understand how the internal structure of the chaotic invariants is modified and how more symbolic sequences are allowed. Furthermore, the results allow us to conjecture that, for these systems, the limit template when the small parameter ε, which controls the slow gating variable, tends to zero is the complete Smale topological template.


Assuntos
Modelos Neurológicos , Neurônios , Humanos
7.
Front Psychiatry ; 12: 648501, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33776822

RESUMO

Introduction: Little is known about the impact of restrictive measures during the COVID-19 pandemic on self-image and engagement in exercise and other coping strategies alongside the use of image and performance-enhancing drugs (IPEDs) to boost performance and appearance. Objectives: To assess the role of anxiety about appearance and self-compassion on the practice of physical exercise and use of IPEDs during lockdown. Methods: An international online questionnaire was carried out using the Exercise Addiction Inventory (EAI), the Appearance Anxiety Inventory (AAI), and the Self-Compassion Scale (SCS) in addition to questions on the use of IPEDs. Results: The sample consisted of 3,161 (65% female) adults from Italy (41.1%), Spain (15.7%), the United Kingdom (UK) (12.0%), Lithuania (11.6%), Portugal (10.5%), Japan (5.5%), and Hungary (3.5%). The mean age was 35.05 years (SD = 12.10). Overall, 4.3% of the participants were found to engage in excessive or problematic exercise with peaks registered in the UK (11.0%) and Spain (5.4%). The sample reported the use of a wide range of drugs and medicines to boost image and performance (28%) and maintained use during the lockdown, mostly in Hungary (56.6%), Japan (46.8%), and the UK (33.8%), with 6.4% who started to use a new drug. Significant appearance anxiety levels were found across the sample, with 18.1% in Italy, 16.9% in Japan, and 16.7% in Portugal. Logistic regression models revealed a strong association between physical exercise and IPED use. Anxiety about appearance also significantly increased the probability of using IPEDs. However, self-compassion did not significantly predict such behavior. Anxiety about appearance and self-compassion were non-significant predictors associated with engaging in physical exercise. Discussion and Conclusion: This study identified risks of problematic exercising and appearance anxiety among the general population during the COVID-19 lockdown period across all the participating countries with significant gender differences. Such behaviors were positively associated with the unsupervised use of IPEDs, although no interaction between physical exercise and appearance anxiety was observed. Further considerations are needed to explore the impact of socially restrictive measures among vulnerable groups, and the implementation of more targeted responses.

8.
J Inorg Biochem ; 218: 111403, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33730639

RESUMO

The problems of resistance and side effects associated with cisplatin and other chemotherapeutic drugs have boosted research aimed at finding new compounds with improved properties. The use of platinum(IV) prodrugs is one alternative, although there is some controversy regarding the predictive ability of the peak reduction potentials. In the work described here a series of fourteen chloride Pt(II) and Pt(IV) compounds was synthesised and fully characterised. The compounds contain different bidentate arylazole heterocyclic ligands. Their cytotoxic properties against human lung carcinoma (A549), human breast carcinoma (MCF7) and human colon carcinoma (HCT116 and HT29) cell lines were studied. A clear relationship between the type of ligand and the anti-proliferative properties was found, with the best results obtained for the Pt(II) compound that contains an aniline fragment, (13), thus evidencing a positive effect of the NH2 group. Stability and aquation studies in DMSO, DMF and DMSO/water mixtures were carried out on the active complexes and an in-depth analysis of the two aquation processes, including DFT analysis, of 13 was undertaken. It was verified that DNA was the target and that cell death occurred by apoptosis in the case of 13. Furthermore, the cytotoxic derivatives did not exhibit haemolytic activity. The reduction of the Pt(IV) compounds whose Pt(II) congeners were active was studied by several techniques. It was concluded that the peak reduction potential was not useful to predict the ability for reduction. However, a correlation between the cytotoxic activity and the standard reduction potential was found.


Assuntos
Compostos de Anilina/química , Antineoplásicos/farmacologia , Neoplasias/tratamento farmacológico , Compostos Organoplatínicos/farmacologia , Platina/química , Pró-Fármacos/farmacologia , Células A549 , Antineoplásicos/química , Apoptose , Proliferação de Células , Células HCT116 , Humanos , Células MCF-7 , Neoplasias/patologia , Compostos Organoplatínicos/química , Pró-Fármacos/química
9.
J Radiosurg SBRT ; 6(1): 45-54, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30775074

RESUMO

PURPOSE: This study aims to estimate a realistic margin in stereotactic body radiotherapy (SBRT) through examining the determination uncertainties of gross tumour volume (GTV). METHODS: Three computed tomography (CT) scans were performed on each patient in different sessions as a treatment simulation. Registration of the different CT image sets was based on the fiducial marks from two stereotactic guides. GTV was defined in each one of them, as well as both the encompassing (UNI) and overlapping (INT) volumes. This protocol was altered following imaging guided radiotherapy (IGRT) implementation, so tumour displacements could be corrected for. The patient was scanned without repositioning solely considering tumour intrafraction variations. In addition, isocentre and dimension variations were obtained for each patient and cohort. A Monte Carlo code was developed to simulate tumour volume, considering them as ellipsoids in order to study their behaviour. Lastly, the equivalent radius (R eq) was defined for each of these volumes, experimental and simulated, and both and values were derived by simple linear regression to the mean value . RESULTS: The global margin M can be defined as this systematic error plus an additional residual random uncertainty, with values M = 3.4 mm for Body Frame, M = 2.3 mm for BodyFIX and M = 2.1 mm without repositioning. The experimental results obtained are in good agreement with simulated values, validating the use of the Monte Carlo code to calculate a margin formula. CONCLUSIONS: Introducing IGRT is not enough to obtain a zero margin; consequently, the safety margin, dependent on tumour shape and size dispersion, can be evaluated using this formulation.

10.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28676437

RESUMO

INTRODUCTION: At least 10% of patients with Obsessive-compulsive Disorder (OCD) are refractory to psychopharmacological treatment. The emergence of new technologies for the modulation of altered neuronal activity in Neurosurgery, deep brain stimulation (DBS), has enabled its use in severe and refractory OCD cases. The objective of this article is to review the current scientific evidence on the effectiveness and applicability of this technique to refractory OCD. METHOD: We systematically reviewed the literature to identify the main characteristics of deep brain stimulation, its use and applicability as treatment for obsessive-compulsive disorder. Therefore, we reviewed PubMed/Medline, Embase and PsycINFO databases, combining the key-words 'Deep brain stimulation', 'DBS' and 'Obsessive-compulsive disorder' 'OCS'. The articles were selected by two of the authors independently, based on the abstracts, and if they described any of the main characteristics of the therapy referring to OCD: applicability; mechanism of action; brain therapeutic targets; efficacy; side-effects; co-therapies. All the information was subsequently extracted and analysed. RESULTS: The critical analysis of the evidence shows that the use of DBS in treatment-resistant OCD is providing satisfactory results regarding efficacy, with assumable side-effects. However, there is insufficient evidence to support the use of any single brain target over another. Patient selection has to be done following analyses of risks/benefits, being advisable to individualize the decision of continuing with concomitant psychopharmacological and psychological treatments. CONCLUSIONS: The use of DBS is still considered to be in the field of research, although it is increasingly used in refractory-OCD, producing in the majority of studies significant improvements in symptomatology, and in functionality and quality of life. It is essential to implement random and controlled studies regarding its long-term efficacy, cost-risk analyses and cost/benefit.


Assuntos
Estimulação Encefálica Profunda , Transtorno Obsessivo-Compulsivo/terapia , Terapia Combinada , Estimulação Encefálica Profunda/efeitos adversos , Estimulação Encefálica Profunda/métodos , Humanos , Qualidade de Vida , Medição de Risco , Resultado do Tratamento
11.
Am J Respir Crit Care Med ; 198(5): 648-656, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29664672

RESUMO

Rationale: General practitioners play a passive role in obstructive sleep apnea (OSA) management. Simplification of the diagnosis and use of a semiautomatic algorithm for treatment can facilitate the integration of general practitioners, which has cost advantages.Objectives: To determine differences in effectiveness between primary health care area (PHA) and in-laboratory specialized management protocols during 6 months of follow-up.Methods: A multicenter, noninferiority, randomized, controlled trial with two open parallel arms and a cost-effectiveness analysis was performed in six tertiary hospitals in Spain. Sequentially screened patients with an intermediate to high OSA probability were randomized to PHA or in-laboratory management. The PHA arm involved a portable monitor with automatic scoring and semiautomatic therapeutic decision-making. The in-laboratory arm included polysomnography and specialized therapeutic decision-making. Patients in both arms received continuous positive airway pressure treatment or sleep hygiene and dietary treatment alone. The primary outcome measure was the Epworth Sleepiness Scale. Secondary outcomes were health-related quality of life, blood pressure, incidence of cardiovascular events, hospital resource utilization, continuous positive airway pressure adherence, and within-trial costs.Measurements and Main Results: In total, 307 patients were randomized and 303 were included in the intention-to-treat analysis. Based on the Epworth Sleepiness Scale, the PHA protocol was noninferior to the in-laboratory protocol. Secondary outcome variables were similar between the protocols. The cost-effectiveness relationship favored the PHA arm, with a cost difference of €537.8 per patient.Conclusions: PHA management may be an alternative to in-laboratory management for patients with an intermediate to high OSA probability. Given the clear economic advantage of outpatient management, this finding could change established clinical practice.Clinical trial registered with www.clinicaltrials.gov (NCT02141165).

14.
Arthritis Res Ther ; 19(1): 174, 2017 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-28738907

RESUMO

BACKGROUND: Dermatomyositis (DM) is inflammatory myopathy or myositis characterized by muscle weakness and skin manifestations. In the differential diagnosis of DM the evaluation of the muscle biopsy is of importance among other parameters. Perifascicular atrophy in the muscle biopsy is considered a hallmark of DM. However, perifascicular atrophy is not observed in all patients with DM and, conversely, perifascicular atrophy can be observed in other myositis such as antisynthetase syndrome (ASS), complicating DM diagnosis. Retinoic acid inducible-gene I (RIG-I), a receptor of innate immunity that promotes type I interferon, was observed in perifascicular areas in DM. We compared the value of RIG-I expression with perifascicular atrophy as a biomarker of DM. METHODS: We studied by immunohistochemical analysis the expression of RIG-I and the presence of perifascicular atrophy in 115 coded muscle biopsies: 44 patients with DM, 18 with myositis with overlap, 8 with ASS, 27 with non-DM inflammatory myopathy (16 with polymyositis, 6 with inclusion body myositis, 5 with immune-mediated necrotizing myopathy), 8 with muscular dystrophy (4 with dysferlinopathy, 4 with fascioscapulohumeral muscle dystrophy) and 10 healthy controls. RESULTS: We found RIG-I-positive fibers in 50% of DM samples vs 11% in non-DM samples (p < 0.001). Interestingly, RIG-I staining identified 32% of DM patients without perifascicular atrophy (p = 0.007). RIG-I sensitivity was higher than perifascicular atrophy (p < 0.001). No differences in specificity between perifascicular atrophy and RIG-I staining were found (92% vs 88%). RIG-I staining was more reproducible than perifascicular atrophy (κ coefficient 0.52 vs 0.37). CONCLUSIONS: The perifascicular pattern of RIG-I expression supports the diagnosis of DM. Of importance for clinical and therapeutic studies, the inclusion of RIG-I in the routine pathological staining of samples in inflammatory myopathy will allow us to gather more homogeneous subgroups of patients in terms of immunopathogenesis.


Assuntos
Proteína DEAD-box 58/análise , Dermatomiosite/diagnóstico , Músculo Esquelético/patologia , Atrofia/patologia , Biomarcadores/análise , Diagnóstico Diferencial , Humanos , Miosite/diagnóstico , Receptores Imunológicos
15.
J Zoo Wildl Med ; 48(1): 250-254, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28363053

RESUMO

Cryptococcosis is a worldwide and potentially fatal mycosis documented in wild and captive koalas ( Phascolarctos cinereus ) caused by Cryptococcus neoformans . Though mainly a subclinical disease, when the nasal cavity is affected, epistaxis, mucopurulent nasal discharge, dyspnea, and facial distortion may occur. This report describes a case of cryptococcosis in a koala where unilateral exophthalmos was the only evident clinical sign and magnetic resonance imaging and computed tomography findings are described. Both advanced imaging techniques should be considered as standard and complementary techniques for nasal cavity evaluation in koalas.


Assuntos
Criptococose/veterinária , Cryptococcus neoformans , Imageamento por Ressonância Magnética/veterinária , Phascolarctidae , Tomografia Computadorizada por Raios X/veterinária , Animais , Animais de Zoológico , Criptococose/diagnóstico por imagem , Criptococose/patologia , Masculino
16.
Aten Primaria ; 49(7): 381-388, 2017.
Artigo em Espanhol | MEDLINE | ID: mdl-28089226

RESUMO

PURPOSE: To analyse the relationship between the type of coping and subjective burden in caregivers of dependent elderly relatives in Andalusia (Spain). DESIGN: Cross-sectional study. LOCATION: Primary Health Care (autonomous community of Andalusia, Spain). PARTICIPANTS: A convenience sample of 198 primary caregivers of dependent elderly relatives. KEY MEASUREMENTS: Coping (Brief COPE), subjective burden (caregiver stress index), objective burden (functional capacity [Barthel Index], cognitive impairment [Pfeiffer Test], behavioural problems of the care recipient [Neuropsychiatric Inventory], and caregivers' dedication to caring), gender and kinship. RESULTS: Most caregivers were women (89.4%), daughters of the care recipient (57.1%), and shared home with him/her (69.7%). On controlling for objective burden, gender and kinship, it was found that subjective burden was positively associated with dysfunctional coping (ß=0.28; P<.001) and negatively with emotion-focused coping (ß=-0.25; P=.001), while no association was found with problem-focused coping. CONCLUSIONS: Dysfunctional coping may be a risk factor for subjective burden, and emotion-focused coping may be a protective factor for that subjective burden regardless of the objective burden, and gender and kinship of the caregivers.

17.
PLoS One ; 10(9): e0137800, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26368127

RESUMO

Differential redox homeostasis in normal and malignant cells suggests that pro-oxidant-induced upregulation of cellular reactive oxygen species (ROS) should selectively target cancer cells without compromising the viability of untransformed cells. Consequently, a pro-oxidant deviation well-tolerated by nonmalignant cells might rapidly reach a cell-death threshold in malignant cells already at a high setpoint of constitutive oxidative stress. To test this hypothesis, we took advantage of a selected number of amine-pyridine-based Fe(II) complexes that operate as efficient and robust oxidation catalysts of organic substrates upon reaction with peroxides. Five of these Fe(II)-complexes and the corresponding aminopyridine ligands were selected to evaluate their anticancer properties. We found that the iron complexes failed to display any relevant activity, while the corresponding ligands exhibited significant antiproliferative activity. Among the ligands, none of which were hemolytic, compounds 1, 2 and 5 were cytotoxic in the low micromolar range against a panel of molecularly diverse human cancer cell lines. Importantly, the cytotoxic activity profile of some compounds remained unaltered in epithelial-to-mesenchymal (EMT)-induced stable populations of cancer stem-like cells, which acquired resistance to the well-known ROS inducer doxorubicin. Compounds 1, 2 and 5 inhibited the clonogenicity of cancer cells and induced apoptotic cell death accompanied by caspase 3/7 activation. Flow cytometry analyses indicated that ligands were strong inducers of oxidative stress, leading to a 7-fold increase in intracellular ROS levels. ROS induction was associated with their ability to bind intracellular iron and generate active coordination complexes inside of cells. In contrast, extracellular complexation of iron inhibited the activity of the ligands. Iron complexes showed a high proficiency to cleave DNA through oxidative-dependent mechanisms, suggesting a likely mechanism of cytotoxicity. In summary, we report that, upon chelation of intracellular iron, the pro-oxidant activity of amine-pyrimidine-based iron complexes efficiently kills cancer and cancer stem-like cells, thus providing functional evidence for an efficient family of redox-directed anti-cancer metallodrugs.


Assuntos
Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Compostos Ferrosos/química , Compostos Ferrosos/farmacologia , Aminas/química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Humanos , Ferro/metabolismo , Quelantes de Ferro/química , Quelantes de Ferro/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Oxidantes/química , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Piridinas/química , Espécies Reativas de Oxigênio/metabolismo
18.
Chaos ; 24(2): 023128, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24985442

RESUMO

We study a plethora of chaotic phenomena in the Hindmarsh-Rose neuron model with the use of several computational techniques including the bifurcation parameter continuation, spike-quantification, and evaluation of Lyapunov exponents in bi-parameter diagrams. Such an aggregated approach allows for detecting regions of simple and chaotic dynamics, and demarcating borderlines-exact bifurcation curves. We demonstrate how the organizing centers-points corresponding to codimension-two homoclinic bifurcations-along with fold and period-doubling bifurcation curves structure the biparametric plane, thus forming macro-chaotic regions of onion bulb shapes and revealing spike-adding cascades that generate micro-chaotic structures due to the hysteresis.


Assuntos
Potenciais de Ação/fisiologia , Modelos Neurológicos , Neurônios/fisiologia , Dinâmica não Linear , Análise Numérica Assistida por Computador
20.
AIDS ; 26(14): 1829-34, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-22410685

RESUMO

OBJECTIVES: To compare causes of death (CoDs) from two independent sources: National Basic Death File (NBDF) and deaths reported to the Spanish HIV Research cohort [Cohort de adultos con infección por VIH de la Red de Investigación en SIDA CoRIS)] and compare the two coding algorithms: International Classification of Diseases, 10th revision (ICD-10) and revised version of Coding Causes of Death in HIV (revised CoDe). METHODS: Between 2004 and 2008, CoDs were obtained from the cohort records (free text, multiple causes) and also from NBDF (ICD-10). CoDs from CoRIS were coded according to ICD-10 and revised CoDe by a panel. Deaths were compared by 13 disease groups: HIV/AIDS, liver diseases, malignancies, infections, cardiovascular, blood disorders, pulmonary, central nervous system, drug use, external, suicide, other causes and ill defined. RESULTS: There were 160 deaths. Concordance for the 13 groups was observed in 111 (69%) cases for the two sources and in 115 (72%) cases for the two coding algorithms. According to revised CoDe, the commonest CoDs were HIV/AIDS (53%), non-AIDS malignancies (11%) and liver related (9%), these percentages were similar, 57, 10 and 8%, respectively, for NBDF (coded as ICD-10). When using ICD-10 to code deaths in CoRIS, wherein HIV infection was known in everyone, the proportion of non-AIDS malignancies was 13%, liver-related accounted for 3%, while HIV/AIDS reached 70% due to liver-related, infections and ill-defined causes being coded as HIV/AIDS. CONCLUSION: There is substantial variation in CoDs in HIV-infected persons according to sources and algorithms. ICD-10 in patients known to be HIV-positive overestimates HIV/AIDS-related deaths at the expense of underestimating liver-related diseases, infections and ill defined causes. CoDe seems as the best option for cohort studies.


Assuntos
Síndrome da Imunodeficiência Adquirida/mortalidade , Algoritmos , Doenças Cardiovasculares/mortalidade , Hepatopatias/mortalidade , Neoplasias/mortalidade , Transtornos Relacionados ao Uso de Substâncias/mortalidade , Adulto , Análise de Variância , Causas de Morte/tendências , Estudos de Coortes , Atestado de Óbito , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vigilância da População , Espanha/epidemiologia
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