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1.
Function (Oxf) ; 3(5): zqac043, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36168588

RESUMO

Telomerase reverse transcriptase (TERT) (catalytic subunit of telomerase) is linked to the development of coronary artery disease (CAD); however, whether the role of nuclear vs. mitchondrial actions of TERT is involved is not determined. Dominant-negative TERT splice variants contribute to decreased mitochondrial integrity and promote elevated reactive oxygen species production. We hypothesize that a decrease in mitochondrial TERT would increase mtDNA damage, promoting a pro-oxidative redox environment. The goal of this study is to define whether mitochondrial TERT is sufficient to maintain nitric oxide as the underlying mechanism of flow-mediated dilation by preserving mtDNA integrity.Immunoblots and quantitative polymerase chain reaction were used to show elevated levels of splice variants α- and ß-deletion TERT tissue from subjects with and without CAD. Genetic, pharmacological, and molecular tools were used to manipulate TERT localization. Isolated vessel preparations and fluorescence-based quantification of mtH2O2 and NO showed that reduction of TERT in the nucleus increased flow induced NO and decreased mtH2O2 levels, while prevention of mitochondrial import of TERT augmented pathological effects. Further elevated mtDNA damage was observed in tissue from subjects with CAD and initiation of mtDNA repair mechanisms was sufficient to restore NO-mediated dilation in vessels from patients with CAD. The work presented is the first evidence that catalytically active mitochondrial TERT, independent of its nuclear functions, plays a critical physiological role in preserving NO-mediated vasodilation and the balance of mitochondrial to nuclear TERT is fundamentally altered in states of human disease that are driven by increased expression of dominant negative splice variants.


Assuntos
Doença da Artéria Coronariana , Telomerase , Humanos , Telomerase/genética , Peróxido de Hidrogênio/metabolismo , Doença da Artéria Coronariana/genética , Vasodilatação , Oxirredução
2.
Nature ; 604(7905): 280-286, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35418631

RESUMO

Multijunction solar cells can overcome the fundamental efficiency limits of single-junction devices. The bandgap tunability of metal halide perovskite solar cells renders them attractive for multijunction architectures1. Combinations with silicon and copper indium gallium selenide (CIGS), as well as all-perovskite tandem cells, have been reported2-5. Meanwhile, narrow-gap non-fullerene acceptors have unlocked skyrocketing efficiencies for organic solar cells6,7. Organic and perovskite semiconductors are an attractive combination, sharing similar processing technologies. Currently, perovskite-organic tandems show subpar efficiencies and are limited by the low open-circuit voltage (Voc) of wide-gap perovskite cells8 and losses introduced by the interconnect between the subcells9,10. Here we demonstrate perovskite-organic tandem cells with an efficiency of 24.0 per cent (certified 23.1 per cent) and a high Voc of 2.15 volts. Optimized charge extraction layers afford perovskite subcells with an outstanding combination of high Voc and fill factor. The organic subcells provide a high external quantum efficiency in the near-infrared and, in contrast to paradigmatic concerns about limited photostability of non-fullerene cells11, show an outstanding operational stability if excitons are predominantly generated on the non-fullerene acceptor, which is the case in our tandems. The subcells are connected by an ultrathin (approximately 1.5 nanometres) metal-like indium oxide layer with unprecedented low optical/electrical losses. This work sets a milestone for perovskite-organic tandems, which outperform the best p-i-n perovskite single junctions12 and are on a par with perovskite-CIGS and all-perovskite multijunctions13.


Assuntos
Compostos de Cálcio , Índio , Cobre , Óxidos , Titânio
3.
Heliyon ; 7(6): e07252, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34195402

RESUMO

INTRODUCTION: The substitution of reference drugs for similar, new or existing drugs in the market is a dilemma present in daily dental procedures. In order to decide whether or not to adopt a new drug in relation to the reference, a clinical trial can provide the necessary evidence. METHODS: A total of 179 healthy volunteers (18-25 years) requiring extraction of mandibular third molars completed the study. Subjects were randomized into 4 groups: right, left, Arteek-SP and Septanest. Allocations consisted of 4% Articaine hydrochloride with 1:10000 epinephrine. The primary aim of this randomized controlled trial was to determine whether the test drug Arteek-SP was noninferior by a margin of 10% in the proportion of patients with total absence of pain, compared to the reference drug Septanest in the extraction of mandibular third molars using inferior alveolar nerve blocks. Secondary outcomes included, hemodynamic parameters, volume (mL), pain scores assessed during one visit and reported postoperative discomfort assessed during 8 days. Noninferiority was declared if total absence of pain for both groups was equal to 0.9, with a significance level of 5% (P < 0.05) and power at 90% (ß = 0.1) at 95% confidence level. RESULTS: Arteek-SP was applied during the first surgery to 90 volunteers (50.28%) and Septanest was applied to 89 subjects (49.72%). Less than 10% difference was identified, in the proportion of patients with total absence of tooth pain P < 0.05 and in the gum P < 0.1, at 95% CI, when Arteek-SP was applied first in comparison with Septanest, establishing noninferiority. CONCLUSION: The clinical performance of the test drug Arteek-SP is noninferior to the reference drug Septanest. They can be considered interchangeable in terms of cost or convenience. REGISTRATION: ClinicalTrials.org, number NCT4166890.

6.
J Psychopharmacol ; 33(3): 335-346, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30355025

RESUMO

BACKGROUND: The prevalence of binge drinking has risen in recent years. It is associated with a range of neurocognitive deficits among adolescents and young emerging adults who are especially vulnerable to alcohol use. Attention is an essential dimension of executive functioning and attentional disturbances may be associated with hazardous drinking. The aim of the study was to examine the oscillatory neural dynamics of attentional control during visual target detection in emerging young adults as a function of binge drinking. METHOD: In total, 51 first-year university students (18 ± 0.6 years) were assigned to light drinking ( n = 26), and binge drinking ( n = 25) groups based on their alcohol consumption patterns. A high-density magnetoencephalography signal was combined with structural magnetic resonance imaging in an anatomically constrained magnetoencephalography model to estimate event-related source power in a theta (4-7 Hz) frequency band. Phase-locked co-oscillations were further estimated between the principally activated regions during task performance. RESULTS: Overall, the greatest event-related theta power was elicited by targets in the right inferior frontal cortex and it correlated with performance accuracy and selective attention scores. Binge drinkers exhibited lower theta power and dysregulated oscillatory synchrony to targets in the right inferior frontal cortex, which correlated with higher levels of alcohol consumption. CONCLUSIONS: These results confirm that a highly interactive network in the right inferior frontal cortex subserves attentional control, revealing the importance of theta oscillations and neural synchrony for attentional capture and contextual maintenance. Attenuation of theta power and synchronous interactions in binge drinkers may indicate early stages of suboptimal integrative processing in young, highly functioning binge drinkers.


Assuntos
Atenção/efeitos dos fármacos , Consumo Excessivo de Bebidas Alcoólicas/psicologia , Magnetoencefalografia , Ritmo Teta/efeitos dos fármacos , Adolescente , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/psicologia , Consumo de Álcool na Faculdade , Função Executiva/efeitos dos fármacos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudantes/psicologia , Universidades
7.
Oncol Rep ; 40(6): 3593-3602, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30542732

RESUMO

Testicular germ cell tumors (TGCTs) are highly sensitive to cisplatin­based chemotherapy. Nevertheless, there are metastatic tumors that do not completely respond to front­line chemotherapy. For these tumors, surgical resection of residual masses is necessary to achieve long­term disease control. Resected tissues represent valuable clinical material, which may be used for the engraftment into immunocompromised mice to produce patient­derived xenografts (PDXs). They typically maintain similarities to the parental tumors and therefore serve as more realistic preclinical models. Moreover, a correlation between PDX treatment outcomes and clinical response to chemotherapy has been previously described. The aim of the present study was to establish and characterize TGCT patient­derived xenografts. These originated from retroperitoneal lymph node metastases infiltrated with TGCTs following previous cisplatin­based chemotherapy, in order to analyze novel treatment options for cisplatin­resistant testicular tumors. We generated two testicular patient­derived xenograft models in SCID beige male mice. Immunohistochemical analyses demonstrated that histological characteristics of the primary tumor were not retained, and transformation into lymphoma, and eventually plasmocytoma, was observed. A potential explanation for the lymphoma transformation observed in PDXs may include tumor­infiltrating lymphocytes (TILs) in xenografted samples of patients, which are transformed following engraftment into immunodeficient recipient mice. Based on these data, we indicated that lymphomagenesis prevention and terminal differentiation represent new challenges in the establishment of PDX models derived from patients with germ cell tumors.


Assuntos
Transformação Celular Neoplásica/patologia , Linfócitos do Interstício Tumoral/transplante , Linfoma/patologia , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Testiculares/patologia , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Adulto , Animais , Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Humanos , Linfonodos/citologia , Linfonodos/patologia , Metástase Linfática , Linfócitos do Interstício Tumoral/patologia , Masculino , Camundongos , Camundongos SCID , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/terapia , Neoplasias Testiculares/terapia , Testículo/patologia , Testículo/cirurgia
8.
J Hosp Infect ; 96(4): 336-341, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28545828

RESUMO

BACKGROUND: Invasive aspergillosis (IA) is a significant problem in acute leukaemia patients. Construction work near hospital wards caring for immunocompromised patients is one of the main risk factors for developing invasive pulmonary aspergillosis (IPA). AIM: To assess the impact of environmental control measures used during hospital construction for the prevention of IA in acute leukaemia patients. METHODS: A retrospective cohort study was developed to evaluate the IA incidence in acute leukaemia patients with different environmental control measures employed during hospital construction. We used European Organisation for the Research and Treatment of Cancer (EORTC) criterial diagnosis parameters for definition of IA. FINDINGS: A total of 175 episodes of inpatient care were evaluated, 62 of which did not have any environmental control measures (when an outbreak occurred), and 113 that were subject to environmental control measures directed to preventing IA. The study showed an IA incidence of 25.8% for the group without environmental control measures vs 12.4% for those who did receive environmental control measures (P=0.024). The relative risk for IA was 0.595 (95% confidence interval: 0.394-0.897) for the group with environmental control measures. CONCLUSION: The current study suggests that the implementation of environmental control measures during a hospital construction has a positive impact for prevention of IA in patients hospitalized with acute leukaemia.


Assuntos
Arquitetura Hospitalar , Hospedeiro Imunocomprometido , Controle de Infecções/métodos , Aspergilose Pulmonar Invasiva/prevenção & controle , Leucemia/complicações , Adolescente , Adulto , Idoso , Feminino , Humanos , Incidência , Aspergilose Pulmonar Invasiva/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
9.
Osteoporos Int ; 28(7): 2187-2193, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28341900

RESUMO

The majority of tumor-induced osteomalacia cases have been reported in the Northern Hemisphere and Asia. In this first series of South American patients, we show that the clinical presentation and sensitivity of plasmatic fibroblast growth factor 23 and somatostatin analog-based imaging are similar to those described in other populations. INTRODUCTION: Describe the experience of clinical presentation, diagnostic study, and treatment of patients with tumor-induced osteomalacia (TIO) in a South American academic center in comparison to literature. METHODS: Analysis of the records of patients diagnosed with TIO. The clinical presentation, diagnostic studies, and treatment were analyzed. Fibroblast growth factor 23 (FGF23) was measured by ELISA. RESULTS: Six patients were diagnosed with TIO during the studied period. The patients' median age was 53 years (range 22-64). All patients presented with weakness and pain in the extremities. Four experienced fractures during their evolution. The median time to diagnosis was 4.5 years (1-20). Biochemical studies showed hypophosphatemia, median of 1.4 mg/dL (1.2-1.6), with low maximum rates of tubular reabsorption of phosphate adjusted for glomerular filtration rate. FGF23 was elevated in 4/6 patients and inappropriately normal in the other two. In three patients, the location of the tumor was clinically evident and confirmed with anatomical imaging. In the remaining patients, two tumors were located with 68Ga DOTATATE-PET/CT and one with OctreoScan. The causal tumors were located in the lower extremities in five patients and invading the frontal sinus in one patient. In all patients, tumors were successfully removed. Within 14 days, there was normalization of phosphate and FGF23 levels and resolution of clinical symptoms in all patients. In all cases, the histopathology was compatible with a phosphaturic mesenchymal tumor. CONCLUSIONS: The clinical presentation, delay time to diagnosis, FGF23 diagnostic sensitivity and histopathology in this first series of South American patients is similar to those described in other populations. The success of localization by somatostatin analog-based imaging, suggests this may the optimal imaging modality.


Assuntos
Neoplasias de Tecido Conjuntivo/diagnóstico , Adulto , Biomarcadores Tumorais/sangue , Neoplasias Ósseas/complicações , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/cirurgia , Feminino , Fator de Crescimento de Fibroblastos 23 , Fatores de Crescimento de Fibroblastos/sangue , Fraturas Espontâneas/diagnóstico por imagem , Fraturas Espontâneas/etiologia , Humanos , Hipofosfatemia/etiologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias de Tecido Conjuntivo/complicações , Neoplasias de Tecido Conjuntivo/cirurgia , Octreotida/análogos & derivados , Compostos Organometálicos , Osteomalacia , Síndromes Paraneoplásicas/diagnóstico , Síndromes Paraneoplásicas/etiologia , Síndromes Paraneoplásicas/cirurgia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Retrospectivos , Neoplasias de Tecidos Moles/complicações , Neoplasias de Tecidos Moles/diagnóstico , Neoplasias de Tecidos Moles/cirurgia , Adulto Jovem
10.
Neuroscience ; 317: 76-107, 2016 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-26772433

RESUMO

Large conductance voltage and calcium-activated potassium (MaxiK) channels are activated by membrane depolarization and elevated cytosolic Ca(2+). In the brain, they localize to neurons and astrocytes, where they play roles such as resetting the membrane potential during an action potential, neurotransmitter release, and neurovascular coupling. MaxiK channels are known to associate with several modulatory proteins and accessory subunits, and each of these interactions can have distinct physiological consequences. To uncover new players in MaxiK channel brain physiology, we applied a directed proteomic approach and obtained MaxiK channel pore-forming α subunit brain interactome using specific antibodies. Controls included immunoprecipitations with rabbit immunoglobulin G (IgG) and with anti-MaxiK antibodies in wild type and MaxiK channel knockout mice (Kcnma1(-/-)), respectively. We have found known and unreported interactive partners that localize to the plasma membrane, extracellular space, cytosol and intracellular organelles including mitochondria, nucleus, endoplasmic reticulum and Golgi apparatus. Localization of MaxiK channel to mitochondria was further confirmed using purified brain mitochondria colabeled with MitoTracker. Independent proof of MaxiK channel interaction with previously unidentified partners is given for GABA transporter 3 (GAT3) and heat shock protein 60 (HSP60). In human embryonic kidney 293 cells containing SV40 T-antigen (HEK293T) cells, both GAT3 and HSP60 coimmunoprecipitated and colocalized with MaxiK channel; colabeling was observed mainly at the cell periphery with GAT3 and intracellularly with HSP60 with protein proximity indices of ∼ 0.6 and ∼ 0.4, respectively. In rat primary hippocampal neurons, colocalization index was identical for GAT3 (∼ 0.6) and slightly higher for HSP60 (∼ 0.5) association with MaxiK channel. The results of this study provide a complete interactome of MaxiK channel the mouse brain, further establish the localization of MaxiK channel in the mouse brain mitochondria and demonstrate the interaction of MaxiK channel with GAT3 and HSP60 in neurons. The interaction of MaxiK channel with GAT3 opens the possibility of a role of MaxiK channel in GABA homeostasis and signaling.


Assuntos
Encéfalo/metabolismo , Chaperonina 60/metabolismo , Proteínas da Membrana Plasmática de Transporte de GABA/metabolismo , Regulação da Expressão Gênica/genética , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Animais , Animais Recém-Nascidos , Encéfalo/citologia , Células Cultivadas , Ciclo-Oxigenase 2/metabolismo , Células HEK293 , Hipocampo/citologia , Hipocampo/ultraestrutura , Humanos , Canais de Potássio Ativados por Cálcio de Condutância Alta/genética , Masculino , Camundongos , Camundongos Transgênicos , Mitocôndrias/metabolismo , Modelos Moleculares , Neurônios/metabolismo , Proteômica , Transfecção
11.
Neoplasma ; 62(4): 521-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25997965

RESUMO

Mesenchymal stromal cells (MSC) exhibit beneficial properties to serve as cellular vehicles for enzyme/prodrug cancer gene therapy approaches. We have previously shown that engineered human adipose tissue-derived MSC in combination with non-toxic prodrug mediated substantial cytotoxic and antitumor effect. The aim of this study was to develop advanced 3D cultivation method to serve for modelling of the therapeutic outcome in vitro. We have used engineered MSC expressing fusion transgene cytosine deaminase::uracilphosphoribosyltransferase (CD-MSC) in combination with prodrug 5-fluorocytosine (5FC). This therapeutic regimen designated CD-MSC/5FC was combined with the human melanoma cells A375 or EGFP-A375 in both standard monolayer culture and 3-dimensional (3D) multicellular nodules. The extent of cytotoxicity was evaluated by standard viability assay MTS, ATP-based luminescence assay, fluorimetric test, measurement of Caspase-3/7 activation and DNA laddering. The data have shown that the extent of cytotoxic bystander effect mediated by CD-MSC/5FC is significantly lower in 3D culture conditions. However, these data better recapitulate the therapeutic efficiency as observed previously in vivo. We suggest here to use the 3D multicellular culture conditions for better prediction of the therapeutic outcome in mouse xenograft models.

12.
Kasmera ; 42(1): 32-40, jun. 2014. tab
Artigo em Espanhol | LILACS | ID: lil-746299

RESUMO

Evaluar la sensibilidad y especificidad de tres técnicas de laboratorio para el diagnóstico de Giardia intestinalis. Materiales y Métodos: 31 muestras de heces provenientes de niños en edad preescolar, se procesaron a través del examen microscópico con SSF-lugol, método de concentración de Ritchie y método inmunológico “Giardia-Strip”. La Técnica de Ritchie fue considerada como “Gold Standard”. Resultados: Se identificaron quistes de Giardia intestinalis en 6 muestras (19,35%) a través de la técnica de Ritchie. La técnica del examen al fresco identificó en 5 de ellas quistes del protozoario (16,1%), mostrando una sensibilidad de 83% y especificidad del 100%. La técnica Giardia-Strip identificó quistes en 4 muestras (12,9%) con sensibilidad de 66,66% y especificidad del 100%. El valor predictivo positivo para el método de “Giardia-Strip” fue 14% y valor predictivo negativo de 93%. El examen al fresco mostró valor predictivo positivo del 100% y valor predictivo negativo de 96%. Conclusiones: El concentrado de Ritchie y el examen al fresco mostraron mayor sensibilidad y especificidad en el diagnóstico de Giardia intestinalis, cuando las muestras contienen solo quistes. Sin embargo, el método Giardia-Strip, demostró mayor rapidez en la obtención de los resultados.


Objective: To evaluate the sensitivity and specificity of three laboratory techniques for the diagnosis of Giardia intestinalis. Materials and Methods: 31 fecal samples from preschoolers were submitted to microscopic examination with SSF-Lugol, the Ritchie concentration method and the “Giardia-Strip” immunological method. The Ritchie technique was considered the “gold standard.“ Results: G. intestinalis cysts were identified in 6 samples (19.35%) using the Ritchie technique. The fresh test identified 5 cases of protozoan cysts (16.1%), showing a sensitivity of 83 % and specificity of 100 %. The Giardia-Strip identified cysts in 4 samples (12.9%) with 66.66 % sensitivity and 100% specificity. The positive predictive value for the “Giardia Strip” method was 14% and the negative predictive value was 93%. The fresh test showed a positive predictive value of 100% and a negative predictive value of 96 %. Conclusions: Ritchie concentrate and the fresh test showed higher sensitivity and specificity in the diagnosis of Giardia intestinalis, when samples contain only cysts. However, the Giardia-Strip method proved faster in obtaining results.

13.
J Hazard Mater ; 199-200: 186-92, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22104763

RESUMO

Biological treatment of Cr(VI) contaminated waters was performed in fixed bed reactors inoculated with SRB (sulphate-reducing bacteria) growing on ethanol. Treatment efficiency was evaluated by checking chemical abatement of Cr(VI) and by ecotoxicological tests using the nematode Caenorhabditis elegans. A preliminary comparison between ethanol and lactate was performed, denoting that using ethanol, the same values of final sulphate abatement were obtained. In addition ethanol showed to be a substrate more competitive than lactate in kinetic terms. Fixed bed column reactors were continuously fed with a solution containing sulphates (3 g L(-1)), ethanol (1.5 g L(-1)) and Cr(VI) (50 mg L(-1)). At steady state the column inoculated with SRB removed 65 ± 5% of sulphate and 95 ± 5% of chromium. Bioactive removal mechanisms predominated over biosorption. Diminution of Cr(VI) toxicity was assessed by using the nematode C. elegans as a test organism showing that the survival of nematodes was 20% in the presence of the untreated influent and raised up to 53% when the nematodes were exposed to the treated effluent.


Assuntos
Bactérias/metabolismo , Biodegradação Ambiental , Cromo/isolamento & purificação , Sulfatos/metabolismo , Poluentes Químicos da Água/isolamento & purificação , Animais , Caenorhabditis elegans/efeitos dos fármacos , Cromo/toxicidade , Poluentes Químicos da Água/toxicidade
14.
Water Res ; 44(1): 151-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19804893

RESUMO

In this work a batch-optimised mixture (w/w %: 6% leaves, 9% compost, 3% Fe(0), 30% silica sand, 30% perlite, 22% limestone) was investigated in a continuous fixed bed column reactor for the treatment of synthetic acid-mine drainage (AMD). A column reactor was inoculated with sulphate-reducing bacteria and fed with a solution containing sulphate and heavy metals (As(V), Cd, Cr(VI), Cu and Zn). At steady state, sulphate abatement was 50+/-10%, while metals were totally removed. A degradation rate constant (k) of 0.015+/-0.001h(-1) for sulphate removal was determined from column data by assuming a first order degradation rate. Reduction of AMD toxicity was assessed by using the nematode Caenorhabditis elegans as a test organism. A lethality assay was performed with the toxicants before and after the treatment, showing that only 5% of the animals were still alive after 48h in presence of the contaminants, while the percentage increased to 73% when the nematodes were exposed to the solution eluted from the column.


Assuntos
Reatores Biológicos/microbiologia , Metais Pesados/metabolismo , Sulfatos/metabolismo , Bactérias Redutoras de Enxofre/metabolismo , Animais , Caenorhabditis elegans/efeitos dos fármacos , Metais Pesados/toxicidade , Testes de Toxicidade , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/toxicidade
15.
J Physiol Sci ; 59(5): 391-6, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19565322

RESUMO

We evaluated changes in passive mechanical properties in cardiac tissues during rat pregnancy. Left and right ventricular free walls were dissected from hearts of nonpregnant, late-pregnant, and postpartum rats. Mechanical experiments in ventricular strips were done by stretch-release cycles using a step motor. The results show that during pregnancy, there is cardiac hypertrophy associated with (1) an increase in myocyte size, particularly of augmented myocyte length, (2) a decrease in passive tension developed by the myocardial walls, and (3) a decrease in both elastic modulus and hysteresis. All changes observed during rat pregnancy were reversed during postpartum. In conclusion, a heart with less ventricular rigidity could contribute to facilitating the ventricular filling in conditions of a greater circulating volume characteristic of pregnancy.


Assuntos
Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Coração/fisiopatologia , Miocárdio/patologia , Complicações Cardiovasculares na Gravidez/patologia , Complicações Cardiovasculares na Gravidez/fisiopatologia , Prenhez/fisiologia , Animais , Fenômenos Biomecânicos , Modelos Animais de Doenças , Elasticidade/fisiologia , Feminino , Contração Miocárdica/fisiologia , Miócitos Cardíacos/patologia , Tamanho do Órgão/fisiologia , Gravidez , Ratos , Ratos Sprague-Dawley
16.
Chemosphere ; 75(8): 1028-34, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19211126

RESUMO

This paper investigates the chemical mechanisms operating in cadmium and lead removal by activated sludge in sequencing batch reactors. Selective extraction and acid digestion of sludge samples denoted that both Cd and Pb are mainly present as surface-bound metals. Characterisation of sludge samples by potentiometric titrations and IR spectra suggested that carboxylic and amino groups are the main active sites responsible for the binding properties of the biomass. Simulation of metal speciation implemented with complexation constants determined in biosorption tests, showed that cadmium predominates as biosorbed species, while lead was mainly removed by precipitation.


Assuntos
Recuperação e Remediação Ambiental/métodos , Metais Pesados/química , Esgotos/química , Poluentes Químicos da Água/química , Adsorção , Algoritmos , Biomassa , Cádmio/química , Chumbo/química , Potenciometria , Espectrofotometria Infravermelho , Propriedades de Superfície
17.
Glia ; 57(12): 1280-95, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19170178

RESUMO

Large-conductance, voltage- and Ca2+-activated K+ channels (MaxiK) are broadly expressed ion channels minimally assembled by four pore-forming alpha-subunits (MaxiKalpha) and typically observed as plasma membrane proteins in various cell types. In murine astrocyte primary cultures, we show that MaxiKalpha is predominantly confined to the microtubule network. Distinct microtubule distribution of MaxiKalpha was visualized by three independent labeling approaches: (1) MaxiKalpha-specific antibodies, (2) expressed EGFP-labeled MaxiKalpha, and (3) fluorophore-conjugated iberiotoxin, a specific MaxiK pore-blocker. This MaxiKalpha association with microtubules was further confirmed by in vitro His-tag pulldown, co-immunoprecipitation from brain lysates, and microtubule depolymerization experiments. Changes in intracellular Ca2+ elicited by general pharmacological agents, caffeine or thapsigargin, resulted in increased MaxiKalpha labeling at the plasma membrane. More notably, U46619, an analog of thromboxane A2 (TXA2), which triggers Ca2+-release pathways and whose levels increase during cerebral hemorrhage/trauma, also elicits a similar increase in MaxiKalpha surface labeling. Whole-cell patch clamp recordings of U46619-stimulated cells develop a approximately 3-fold increase in current amplitude indicating that TXA2 stimulation results in the recruitment of additional, functional MaxiK channels to the surface membrane. While microtubules are largely absent in mature astrocytes, immunohistochemistry results in brain slices show that cortical astrocytes in the newborn mouse (P1) exhibit a robust expression of microtubules that significantly colocalize with MaxiK. The results of this study provide the novel insight that suggests that Ca2+ released from intracellular stores may play a key role in regulating the traffic of intracellular, microtubule-associated MaxiK stores to the plasma membrane of developing murine astrocytes.


Assuntos
Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Cálcio/metabolismo , Fármacos do Sistema Nervoso Central/farmacologia , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Animais , Animais Recém-Nascidos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cafeína/farmacologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Células Cultivadas , Quelantes/farmacologia , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/antagonistas & inibidores , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Microtúbulos/metabolismo , Tapsigargina/farmacologia , Tromboxano A2/análogos & derivados , Tubulina (Proteína)/metabolismo
18.
Med. paliat ; 15(3): 165-170, jul. 2008. tab
Artigo em Es | IBECS | ID: ibc-68008

RESUMO

Introducción: la calidad de vida (CdV) tiene significados distintos según se adapte al concepto intuitivo, al metodológico o al resultado de un cuestionario. Objetivo: conocer el concepto intuitivo de CdV de los profesionales de Cuidados Paliativos para los pacientes que tratan y para ellos mismos. Conocer si se adapta a los cuestionarios validados. Material y métodos: estudio cualitativo y cuantitativo con profesionales de Cuidados Paliativos. Se planteó en pregunta abierta qué comprendían de manera intuitiva como CdV en enfermos terminales y en sí mismos. Dieron luego una estimación del peso relativo de los dominios y de la influencia de diversos problemas en la CdV. Los resultados se compararon con el perfil del QLQ-C15-PAL. Resultados: los principales componentes de la CdV en los pacientes fueron: control de síntomas, dignidad personal, familia y calidad de la atención. Este perfil no coincide con el del QLQ-C15-PAL. En los profesionales, los dominios más relevantes fueron salud, capacidad para disfrutar, familia y relaciones personales. Conclusiones: el perfil de lo que intuitivamente estiman como CdV los profesionales de Cuidados Paliativos es diferente en los pacientes y en ellos mismos. Este concepto no coincide con el modelo de los cuestionarios específicos de CdV en Cuidados Paliativos


Background: health-related quality of life (QoL) may have different meanings when interpreted intuitively, methodologically, or as the result of a questionnaire. Objective: to know the intuitive QoL concept in palliative care professionals regarding both the patients they treat and themselves, and to determine whether such concept is consistent with the measures provided by validated questionnaires. Material and methods: a mixed qualitative and quantitative study was performed in palliative care professionals. An open question asked about their intuitive understanding of QoL for terminal patients and themselves. They did an estimation of the relative weight of different domains, and the influence of several problems. These results were compared to the profile of the QLQ-C15-PAL questionnaire. Results: the estimated most important component of QoL in patients was symptom control, followed by personal dignity, family support, and quality of care. This profile is divergent from that of QLQ-C15-PAL, which is focused on symptoms and performance status. Regarding the QoL of professionals themselves, the most relevant domains were health, ability to enjoy, family, and personal relations. Conclusions: the intuitive QoL profile estimated by palliative care professionals is different for patients and for themselves. This intuitive concept is not consistent with the model presented by specific QoL questionnaires for palliative-care patients


Assuntos
Humanos , Qualidade de Vida/psicologia , Doente Terminal/psicologia , Cuidados Paliativos , Inquéritos e Questionários , Relações Médico-Paciente , Direito a Morrer , Relações Interpessoais , Relações Familiares
19.
Med. paliat ; 15(2): 82-88, abr. 2008. tab
Artigo em Es | IBECS | ID: ibc-67998

RESUMO

Introducción: los pacientes y familiares en Cuidados Paliativos, además de las necesidades vitales básicas, tienen otras necesidades personales y psicosociales. El voluntario en Cuidados Paliativos debe complementarla labor de los profesionales cubriendo estas necesidades, logrando así el mayor bienestar y asegurando la mejor calidad de vida al enfermo. El voluntario es por tanto una pieza decisiva. Objetivo: establecer un plan estratégico consensuado entre diversas entidades para desarrollar un voluntariado en Cuidados Paliativos de alta calidad. Método: se realizó revisión bibliográfica, consulta jurídica especializada, creación de un grupo nominal y validación de acuerdos. Resultados: en relación a la búsqueda bibliográfica finalmente se seleccionaron 18 artículos para su completa lectura. En la consulta jurídica especializada, se encontraron diversos documentos publicados por el Estado Español, Comunidades Autónomas u otros organismos nacionales e internacionales. En la creación del grupo nominal, se eligieron 9 representantes de 8 asociaciones y del Programa Regional de Cuidados Paliativos de Extremadura que estaban dispuestas a participar en el plan del voluntariado. Tras múltiples reuniones se estableció un plan consensuado con 13 objetivos y 18 acciones. Conclusiones: el voluntariado es una vía adecuada para complementar el cuidado y apoyo de los pacientes en fase terminal. En Extremadura, se ha desarrollado un plan con diferentes acciones en el que han participado distintas asociaciones y la administración sanitaria (AU)


Background: Besides basic and vital needs, patients and their families have other personal and psychosocial requirements. Thus, palliative care volunteers must complement professional work by covering these necessities -providing well-being and assuring the best quality of life. A volunteer is therefore a pivotal part in the process. Objective: To establish a consensus strategic plan amongst various organizations for the development of high-quality volunteering. Method: A literature analysis, questions to lawyers, creation of a nominal group, and validation of agreements made. Results: Eighteen articles were selected for complete reading after a bibliographical search. Several documents published by the Spanish State, Spanish Regions, and National or International organisms were found by lawyers. Regarding the formalization of the nominal group, 9 representatives of 8 associations and the Regional Program of Palliative Care of Extremadura were included, and they agreed in participating in volunteering planning. After several meetings a consensus plan was designed including 13 objectives and 18 actions. Conclusions: Volunteering is a suitable way to complement care and support for end-stage patients. In Extremadura a plan with different actions has been developed. Different associations and the Healthcare Administration participated in its development (AU)


Assuntos
Humanos , Trabalhadores Voluntários de Hospital/organização & administração , Doente Terminal/psicologia , Serviços Hospitalares de Assistência Domiciliar , Trabalhadores Voluntários de Hospital/normas , Doente Terminal/legislação & jurisprudência , Serviços Hospitalares de Assistência Domiciliar/organização & administração , Qualidade de Vida , Necessidades e Demandas de Serviços de Saúde
20.
J Hazard Mater ; 156(1-3): 448-57, 2008 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-18242836

RESUMO

In this study, olive pomace, an agricultural waste that is very abundant in Mediterranean area, was modified by two chemical treatments in order to improve its biosorption capacity. Potentiometric titrations and IR analyses were used to characterise untreated olive pomace (OP), olive pomace treated by phosphoric acid (PAOP) and treated by hydrogen peroxide (HPOP). Acid-base properties of all investigated biosorbents were characterised by two main kinds of active sites, whose nature and concentration were determined by a mechanistic model assuming continuous distribution for the proton affinity constants. Titration modelling denoted that all investigated biosorbents (OP, PAOP and HPOP) were characterised by the same kinds of active sites (carboxylic and phenolic), but with different total concentrations with PAOP richer than OP and HPOP. Single metal equilibrium studies in batch reactors were carried out to determine the capacity of these sorbents for copper and cadmium ions at constant pH. Experimental data were analysed and compared using the Langmuir isotherm. The order of maximum uptake capacity of copper and cadmium ions on different biosorbents was PAOP>HPOP>OP. The maximum adsorption capacity of copper and cadmium, was obtained as 0.48 and 0.10 mmol/g, respectively, for PAOP. Metal biosorption tests in presence of Na(+) in solution were also carried out in order to evaluate the effect of chemical treatment on biomass selectivity. These data showed that PAOP is more selective for cadmium than the other sorbents, while similar selectivity was observed for copper.


Assuntos
Ácidos/química , Álcalis/química , Cádmio/química , Cobre/química , Resíduos Industriais , Olea , Potenciometria , Espectrofotometria Infravermelho , Termodinâmica
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