562 research outputs found

    Phototriggering of neuroactive amino acids from 5,6-benzocoumarinyl conjugates

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    Uncaging of several neuroactive amino acids, namely β-alanine, tyrosine, 3,4-dihydroxyphenylalanine (DOPA) and glutamic acid from the corresponding 5,6-benzocoumarinyl conjugates was carried out by irradiation at different wavelengths and in different solvent systems. The release of the various amino acids was faster in ACN/HEPES buffer mixtures and for the tyrosine conjugate, an increase in the photolysis reaction rates and the quantitative uncaging of the amino acid was associated with increasing water content in the solvent mixture.Fundação para a Ciência e a Tecnologia (FCT) - REDE/1517/RMN/2005Fundo Europeu de Desenvolvimento Regional (FEDER) - POCI 201

    Assessing anti-malarial drug effects ex vivo using the haemozoin detection assay

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    © 2015 Rebelo et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Background: In vitro sensitivity assays are crucial to detect and monitor drug resistance. Plasmodium falciparum has developed resistance to almost all anti-malarial drugs. Although different in vitro drug assays are available, some of their inherent characteristics limit their application, especially in the field. A recently developed approach based on the flow cytometric detection of haemozoin (Hz) allowed reagent-free monitoring of parasite maturation and detection of drug effects in culture-adapted parasites. In this study, the set-up, performance and usefulness of this novel assay were investigated under field conditions in Gabon. Methods: An existing flow cytometer (Cyflow Blue) was modified on site to detect light depolarization caused by Hz. Blood from malaria patients was incubated for 72 hrs with increasing concentrations of chloroquine, artesunate and artemisinin. The percentage of depolarizing red blood cells (RBC) was used as maturation indicator and measured at 24, 48 and 72 hrs of incubation to determine parasite growth and drug effects. Results: The flow cytometer was easily adapted on site to detect light depolarization caused by Hz. Analysis of ex vivo cultures of parasites, obtained from blood samples of malaria patients, showed four different growth profiles. In 39/46 samples, 50% inhibitory concentrations (IC50) were successfully determined. IC50 values for chloroquine were higher than 200 nM in 70% of the samples, indicating the presence of chloroquine-resistant parasites. For artesunate and artemisinin, IC50 values ranged from 0.9 to 60 nM and from 2.2 nM to 124 nM, respectively, indicating fully sensitive parasites. Conclusion: Flow cytometric detection of Hz allowed the detection of drug effects in blood samples from malaria patients, without using additional reagents or complex protocols. Adjustment of the initial parasitaemia was not required, which greatly simplifies the protocol, although it may lead to different IC50 values. Further investigation of set-up conditions of the Hz assay, as well as future studies in various settings should be performed to further determine the usefulness of this assay as a tool for rapid resistance testing in malaria-endemic countries.This work was supported by the Luso-American Foundation (FLAD-LACR grant: B-A.V-109-09/07). MR acknowledges Fundação para a Ciência e a Tecnologia for doctoral grant (SFRH/BD/84530/2012) and Fundação Calouste Gulbenkian for the Award CAML/Gulbenkian for Travel ACGT fellowship.info:eu-repo/semantics/publishedVersio

    CALCIUM CHANNEL BLOCKER VERAPAMIL STIMULATES OVULATION AND INDUCES FETAL REABSORPTION IN RATS

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    Os bloqueadores dos canais de cálcio são largamente utilizados em distúrbios cardiovasculares, usualmente em tratamentos prolongados, ocasionalmente em mulheres grávidas. Foram estudados os efeitos do verapamil sobre a implantação uterina, a reabsorção fetal e os níveis de cálcio, fosfato e proteínas totais plasmáticos de mães e filhotes. Foram utilizadas 75 ratas fêmeas Wistar, com qualidade controlada. Os animais tratados foram divididos em dois grupos: o primeiro recebeu verapamil na dose 2,4 mg/rato/dia de e o segundo, 24 mg/rato/dia. A droga foi administrado na água de beber durante 10 semanas: 7 semanas antes do acasalamento e 3 semanas durante a gestação, sendo a operação cesariana realizada ao 21º dia. Por ocasião da cesariana, foram tomadas amostras de sangue das mães e filhotes. O verapamil, na dose mais elevada, causou diminuição dos níveis plasmáticos de cálcio e fosfato nas mães a par de diminuir o peso corpóreo dos filhotes. Os níveis séricos de cálcio, fosfato e proteínas foram comparáveis nos filhotes dos grupos controle e tratado. Contudo, foram significativamente mais baixos em todos os filhotes, em comparação com as respectivas mães. Os resultados mostraram que o verapamil estimulou a ovulação, aumentando o número de implantações uterinas, enquanto induziu morte fetal precoce e reabsorção fetal. Abstract Calcium channel blockers are widely used in cardiovascular diseases, usually in long-term treatments, occasionally in pregnant women. The effects of verapamil were studied on uterine implantation, fetal reabsorption and mothers and offsprings plasmatic levels of calcium, phosphate and total protein. Seventy-five quality-controlled female Wistar rats were used. The drug-treated animals were divided in two groups: the first received verapamil in doses of 2.4 mg/rat/day and the second, doses of 24 mg/rat/day. The drug was administered by means of the drinking water for 10 weeks: 7 weeks before mating and 3 weeks during pregnancy; cesarean surgery was performed on the 21st. day. On the occasion of the cesarean, mothers and newborns blood samples were taken. Verapamil, in the higher dose, caused a lowering of plasmatic calcium and phosphate in mothers and reduced body weight in offspring. In the young, plasmatic calcium, phosphate and total proteins were comparable in verapamil treated and control. However, these values were significantly lower in newborn of treated and control groups, as compared to their respective mothers. Results show that verapamil stimulated ovulation, increasing the uterine implantation but induced early fetal death and reabsorption

    Dual augmentation for aerobic bioremediation of MTBE and TCE pollution in heavy metal-contaminated soil

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    In this work we isolated from soil and characterized several bacterial strains capable of either resisting high concentrations of heavy metals (Cd2+ or Hg2+ or Pb2+) or degrading the common soil and groundwater pollutants MTBE (methyl-tertbutyl ether) or TCE (trichloroethylene). We then used soil microcosms exposed to MTBE (50 mg/l) or TCE (50 mg/l) in the presence of one heavy metal (Cd 10 ppm or Hg 5 ppm or Pb 50 or 100 ppm) and two bacterial isolates at a time, a degrader plus a metalresistant strain. Some of these two-membered consortia showed degradation efficiencies well higher (49–182% higher) than those expected under the conditions employed, demonstrating the occurrence of a synergetic relationship between the strains used. Our results show the efficacy of the dual augmentation strategy for MTBE and TCE bioremediation in the presence of heavy metals

    Robot-assisted rehabilitation architecture supported by a distributed data acquisition system

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    Rehabilitation robotics aims to facilitate the rehabilitation procedure for patients and physical therapists. This field has a relatively long history dating back to the 1990s; however, their implementation and the standardisation of their application in the medical field does not follow the same pace, mainly due to their complexity of reproduction and the need for their approval by the authorities. This paper aims to describe architecture that can be applied to industrial robots and promote their application in healthcare ecosystems. The control of the robotic arm is performed using the software called SmartHealth, offering a 2 Degree of Autonomy (DOA). Data are gathered through electromyography (EMG) and force sensors at a frequency of 45 Hz. It also proves the capabilities of such small robots in performing such medical procedures. Four exercises focused on shoulder rehabilitation (passive, restricted active-assisted, free active-assisted and Activities of Daily Living (ADL)) were carried out and confirmed the viability of the proposed architecture and the potential of small robots (i.e., the UR3) in rehabilitation procedure accomplishment. This robot can perform the majority of the default exercises in addition to ADLs but, nevertheless, their limits were also uncovered, mainly due to their limited Range of Motion (ROM) and cost.info:eu-repo/semantics/publishedVersio

    SalivaPRINT Toolkit – protein profile evaluation and phenotype stratification

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    The value of the molecular information obtained from saliva is dependent on the use of in vitro and in silico techniques. The main proteins of saliva when separated by capillary electrophoresis enable the establishment of individual profiles with characteristic patterns reflecting each individual phenotype. Different physiological or pathological conditions may be identified by specific protein profiles. The association of each profile to the particular protein composition provides clues as to which biological processes are compromised in each situation. Patient stratification according to different phenotypes often within a particular disease spectrum is especially important for the management of individuals carrying multiple diseases and requiring personalized interventions. In this work we present the SalivaPRINT Toolkit, which enables the analysis of protein profile patterns and patient phenotyping. Additionally, the SalivaPRINT Toolkit allows the identification of molecular weight ranges altered in a particular condition and therefore potentially involved in the underlying dysregulated mechanisms. This tutorial introduces the use of the SalivaPRINT Toolkit command line interface (https://github.com/salivatec/SalivaPRINT) as an independent tool for electrophoretic protein profile evaluation. It provides a detailed overview of its functionalities, illustrated by the application to the analysis of profiles obtained from a healthy population versus a population affected with inflammatory conditions. Biological significance We present SalivaPRINT, which serves as a patient characterization tool to identify molecular weights related with particular conditions and, from there, find proteins, which may be involved in the underlying dysregulated cellular mechanisms. The proposed analysis strategy has the potential to boost personalized diagnosis. To our knowledge this is the first independent tool for electrophoretic protein profile evaluation and is crucial when a large number of complex electrophoretic profiles needs to be compared and classified.info:eu-repo/semantics/acceptedVersio

    Mushroom-based cosmeceutical ingredients: Microencapsulation and in vitro release profile

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    [EN]Mushrooms can be used as a source of cosmeceutical ingredients. Agaricus bisporus and Pleurotus ostreatus ethanolic extracts present important bioactive properties, but with some compounds showing easy oxidation and degradation. In the present work, microencapsulation by atomization/coagulation technique was used to protect the extracts. The obtained microspheres were characterised in terms of morphology, particle size distribution and encapsulation efficiency. Microencapsulated extracts were incorporated into a semi-solid base cream and their performance compared with the use of the free forms in terms of bioactivity, and in vitro release using the cosmetic matrix and real time conditions (up to 6 months). The physico-chemical properties (colour and pH) of the developed formulations were also monitored over the same time period. The cosmeceutical formulations containing free extracts displayed bioactivity. For the formulations prepared with the encapsulated forms, the release of the extracts was achieved and anti-tyrosinase and antimicrobial activities were observed, while for the antioxidant activity, the extract release over the time was not sufficient to exert an effect. Overall, the use of mushroom extracts in free or encapsulated forms can be an option in cosmeceutical formulations, and the encapsulated forms can allow a controlled release leading to bioactivity control

    EFFECTS OF CALCIUM CHANNELBLOCKER VERAPAMIL ON BONE AND DENTAL GERM IN RATS

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    O verapamil e outros bloqueadores dos canais de cálcio são usados como antihipertensivos e antiarrítmicos tratamentos prolongados ou por toda a vida, podendo ser indicados em gestantes. Foi estudado o efeito do bloqueador dos canais de cálcio sobre o germe dental, tempo de erupção dentária de filhotes nascidos de mães tratadas e mineralização óssea nas mães. As fêmeas tratadas foram divididas em dois grupos: o primeiro recebeu verapamil na dose de 2,4 mg/rato/dia e o segundo, 24 mg/rato/dia. Os animais foram divididas em dois subgrupos: o primeiro recebeu a droga durante 10 semanas: 7 semanas antes do acasalamento e 3 semanas durante a gestação realizando-se a operação cesariana ao 21o dia; o outro foi tratado como o primeiro, porem os filhotes nasceram de parto natural e o tratamento das mães foi continuado por 15 dias. Foram determinados os níveis plasmáticos de cálcio e fosfato de mães e filhotes. As cabeças dos filhotes foram seccionadas para histologia dos germes dentários e determinados os pesos úmido e seco do osso femoral das mães. Os resultados mostraram que a droga, na dose mais elevada, diminuiu os níveis séricos de cálcio e fosfato nas mães, enquanto que nos filhotes, os valores foram significativamente mais baixos em comparação com as mães. O verapamil causou aumento da mineralização óssea nas mães durante a gestação, mas não após o parto. Um aumento da calcificação dos germes dentários dos filhotes não pôde ser demonstrada, porem na dose mais elevada, o verapamil causou retardo significativo na erupção dentária. Abstract Verapamil and other calcium blocker drugs are used as antihypertensive and antiarrhythmic in long term treatments and appropriate to be prescribed for pregnant women. It was studied in rats the effects of verapamil on dental germ calcification, the time of dental eruption in offspring born from treated mothers and on mothers bone mineralization. The rats were divided in two groups: one received verapamil in doses of 2.4 mg/rat/day and the other, 24 mg/rat/day. The animals were divided in two subgroups: one was treated during 10 weeks: 7 before mating and 3 during pregnancy, cesarean surgery performed on the 21st day; the other was treated in the same way but the offspring were born by natural delivery and the mothers treatment continued for 15 days. Plasma calcium and phosphate were assayed in mothers and offspring. The offsprings heads were isolated to histology of dental germs and determined mothers femoral bone fresh and dry weights. Results show that the higher dose verapamil lowered mothers plasmatic calcium and phosphate while a significant lower values were observed in offspring as compared to their mothers. Verapamil increased mothers femoral bone mineralization during mineralization but not after delivery. An increased calcium deposition of dental germ could not be demonstrated but verapamil significantly delayed newborns dental eruption

    Dual-stage triterpenoids from an African medicinal plant targeting the malaria parasite

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    Sixteen triterpenoids (1–16), previously isolated from the aerial parts of the African medicinal plant Momordica balsamina or obtained by derivatization, were evaluated for their activity against liver stages of Plasmodium berghei, measuring the luminescence intensity in Huh-7 cells infected with a firefly lucif erase-expressing P. berghei line, PbGFP-Luccon. Toxicity of compounds (1–16) was assessed on the same cell line through the fluorescence measurement of cell confluency. The highest activity was displayed by a derivative bearing two acetyl residues, karavoate B (7), which led to a dose-dependent decrease in the P. berghei infection rate, exhibiting a very significant activity at the lowest concentration employed (1 lM) and no toxicity towards the Huh-7 cells. It is noteworthy that, in previous studies, this compound was found to be a strong inhibitor of blood-stages of Plasmodium falciparum, thus displaying a dual-stage antimalarial activity.info:eu-repo/semantics/publishedVersio
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