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1.
J Med Syst ; 43(6): 168, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31056720

RESUMO

Cardiovascular disease is the leading cause of death in the world, and its early detection is a key to improving long-term health outcomes. The auscultation of the heart is still an important method in the medical process because it is very simple and cheap. To detect possible heart anomalies at an early stage, an automatic method enabling cardiac health low-cost screening for the general population would be highly valuable. By analyzing the phonocardiogram signals, it is possible to perform cardiac diagnosis and find possible anomalies at an early-term. Therefore, the development of intelligent and automated analysis tools of the phonocardiogram is very relevant. In this work, we use simultaneously collected electrocardiograms and phonocardiograms from the Physionet Challenge database with the main objective of determining whether a phonocardiogram corresponds to a "normal" or "abnormal" physiological state. Our main contribution is the methodological combination of time domain features and frequency domain features of phonocardiogram signals to improve cardiac disease automatic classification. This novel approach is developed using both features. First, the phonocardiogram signals are segmented with an algorithm based on a logistic regression hidden semi-Markov model, which uses electrocardiogram signals as a reference. Then, two groups of features from the time and frequency domain are extracted from the phonocardiogram segments. One group is based on motifs and the other on Mel-frequency cepstral coefficients. After that, we combine these features into a two-dimensional time-frequency heat map representation. Lastly, a binary classifier is applied to both groups of features to learn a model that discriminates between normal and abnormal phonocardiogram signals. In the experiments, three classification algorithms are used: Support Vector Machines, Convolutional Neural Network, and Random Forest. The best results are achieved when both time and Mel-frequency cepstral coefficients features are considered using a Support Vector Machines with a radial kernel.


Assuntos
Algoritmos , Cardiopatias/diagnóstico , Fonocardiografia/métodos , Processamento de Sinais Assistido por Computador , Ruídos Cardíacos , Humanos , Redes Neurais de Computação
2.
Microsc Microanal ; 21(5): 1296-303, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26350278

RESUMO

Frangula azorica V. Grubow is a Macaronesian flora medicinal plant, endemic from Azores islands and inscribed on the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species. This species, known as "sanguinho," belongs to the family Rhamnaceae, the same as Frangula alnus Mill. and Frangula purshiana (DC.) J. G. Cooper, two widely used official laxative herbal medicines of the western Pharmacopoeias constituted by the dried barks of each species. Morphological and chemical studies on F. azorica dried bark are scarce although it is potentially recognized as a Portuguese laxative herbal medicine. Macroscopically, the bark occurs in quills or nearly flat pieces. A channeled external surface with transversely elongated lenticels is characteristic. When the outer phellem layer is removed, a bright purple inner phellem layer is disclosed. Light and electron microscopy observations revealed flattened phellem cells with slightly thickened walls, cortical parenchyma with secretory ducts and groups of sclereids, phloem with groups of fibers and sheaths of parenchymatous cells containing druses or more frequently prismatic crystals of calcium oxalate, and parenchymatous medullary rays one to three cells wide with spherical starch grains. Observation of these botanical characteristics must be included in quality monographs of F. azorica bark herbal medicine.


Assuntos
Microscopia/métodos , Casca de Planta/anatomia & histologia , Plantas Medicinais/anatomia & histologia , Rhamnus/anatomia & histologia , Açores
3.
Plants (Basel) ; 12(15)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37570987

RESUMO

Species of the Diospyros L. genus (Ebenaceae family) have been largely used in traditional medicine for the treatment of several diseases, especially infectious ones. To date, active major compounds such as naphthoquinones, triterpenoids, and tannins have been isolated and pharmacologically validated from Diospyros species. The present study summarizes the information available in the literature on the species described in the Flora of Mozambique. To do so, scientific databases (e.g., PubMed, Scopus, Web of Science, and Google Scholar) were searched using various keywords and Boolean connectors to gather and summarize the information. Of the 31 native and naturalized species in the Flora of Mozambique, 17 are used in different regions of Africa and were described for their traditional uses. They were reported to treat more than 20 diseases, mostly infectious, in the gastrointestinal and oral cavity compartments. This work provides an overview of the therapeutical potential of Diospyros species and explores novel insights on the antimicrobial potential of extracts and/or isolated compounds of these Mozambican species.

4.
Comput Methods Programs Biomed ; 213: 106529, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34839272

RESUMO

BACKGROUND AND OBJECTIVE: Cell migration is essential for many biological phenomena with direct impact on human health and disease. One conventional approach to study cell migration involves the quantitative analysis of individual cell trajectories recorded by time-lapse video microscopy. Dedicated software tools exist to assist the automated or semi-automated tracking of cells and translate these into coordinate positions along time. However, cell biologists usually bump into the difficulty of plotting and computing these data sets into biologically meaningful figures and metrics. METHODS: This report describes MigraR, an intuitive graphical user interface executed from the RStudioTM (via the R package Shiny), which greatly simplifies the task of translating coordinate positions of moving cells into measurable parameters of cell migration (velocity, straightness, and direction of movement), as well as of plotting cell trajectories and migration metrics. One innovative function of this interface is that it allows users to refine their data sets by setting limits based on time, velocity and straightness. RESULTS: MigraR was tested on different data to assess its applicability. Intended users of MigraR are cell biologists with no prior knowledge of data analysis, seeking to accelerate the quantification and visualization of cell migration data sets delivered in the format of Excel files by available cell-tracking software. CONCLUSIONS: Through the graphics it provides, MigraR is an useful tool for the analysis of migration parameters and cellular trajectories. Since its source code is open, it can be subject of refinement by expert users to best suit the needs of other researchers. It is available at GitHub and can be easily reproduced.


Assuntos
Rastreamento de Células , Software , Movimento Celular , Humanos
5.
Plants (Basel) ; 11(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36559618

RESUMO

Diospyros villosa L. (De Winter) (Ebenaceae) is a shrub whose root (DVR) is used as a toothbrush and to treat oral infections in Mozambique. The present work aims at establishing monographic quality criteria to allow the sustainable and safe development of pharmaceutical preparations with this herbal drug. This includes setting botanical (qualitative and quantitative) and chemical identification parameters, purity tests (loss on drying and total ash), quantifying the major classes of constituents identified, and particle size characterization of the powdered drug. DVR samples are cylindrical and microscopically characterized by: a periderm, with six layers of flattened phellem cells, with slightly thickened walls and few layers of phelloderm; cortical parenchyma with brachysclereids with a short, roughly isodiametric form (13.82-442.14 µm2 × 103), surrounded by a ring of prismatic calcium oxalate crystals; uniseriate medullary rays and prominent vessels of the xylem with single or double shape; numerous single and clustered starch grains, within the cortical parenchyma, medullar parenchyma, and ray cells. Polyphenols, mainly hydrolyzable tannins (212.29 ± 0.005 mg gallic acid equivalent/g of dried DVR), are the main marker class of constituents. Furthermore, the average diameter of the particles of the powder, 0.255 mm, allows its classification as a fine powder.

6.
Sci Rep ; 12(1): 4342, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35288615

RESUMO

Large-scale release of isotopically light carbon is responsible for the carbon isotope excursion (CIE) of the Toarcian Oceanic Anoxic Event during the Lower Jurassic. Proposed sources include methane hydrate dissociation, volcanogenic outgassing of carbon dioxide and/or thermogenic methane release from the Karoo-Ferrar magmatic province (southern Africa). Distinct small-scale shifts superimposed on the long-term CIE have been interpreted as rapid methane pulses linked to astronomically forced climate changes. In the Peniche reference section (Portugal), these small-scale shifts correspond to distinct brownish marly layers featuring markedly high mercury (Hg) and magnetic mineral concentration. Total organic carbon and Hg increase are uncorrelated, which suggests input of Hg into the atmosphere, possibly released after the intrusion of the Karoo-Ferrar sills into organic-rich sediments. Enhanced magnetic properties are associated with the presence of martite, washed-in oxidized magnetite, inferred to be due to increased aridity on the continental hinterland. This study provides strong evidence for a direct link between the Karoo-Ferrar magmatism, the carbon-isotope shifts and the resulting environmental changes.


Assuntos
Sedimentos Geológicos , Mercúrio , Atmosfera , Isótopos de Carbono/análise , Metano , Oceanos e Mares
7.
Sci Rep ; 9(1): 19596, 2019 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-31862994

RESUMO

In a circular economy concept, where more than 300 million tons of mining and quarrying wastes are produced annually, those are valuable resources, supplying metals that are extracted today by other processes, if innovative methods and processes for efficient extraction of these elements are applied. This work aims to assess microbiological and chemical spatial distribution within two tailing basins from a tungsten mine, using a MiSeq approach targeting the 16S rRNA gene, to relate microbial composition and function with chemical variability, thus, providing information to enhance the efficiency of the exploitation of these secondary sources. The tailings sediments core microbiome comprised members of family Anaerolineacea and genera Acinetobacter, Bacillus, Cellulomonas, Pseudomonas, Streptococcus and Rothia, despite marked differences in tailings physicochemical properties. The higher contents of Al and K shaped the community of Basin 1, while As-S-Fe contents were correlated with the microbiome composition of Basin 2. The predicted metabolic functions of the microbiome were rich in genes related to metabolism pathways and environmental information processing pathways. An in-depth understanding of the tailings microbiome and its metabolic capabilities can provide a direction for the management of tailings disposal sites and maximize their potential as secondary resources.


Assuntos
Microbiota , Mineração , Microbiologia do Solo , Tungstênio , Acinetobacter , Bacillus , Cellulomonas , Monitoramento Ambiental , Geografia , Metagenoma , Portugal , Pseudomonas , RNA Ribossômico 16S/genética , Streptococcus
8.
Microsc Res Tech ; 78(11): 1001-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26303860

RESUMO

Gymnosporia arenicola Jordaan (Celastraceae) is a shrub or small tree, which naturally occurs in coastal sand dunes of Southern Mozambique and South Africa. Its dried leaf is often used in traditional medicine for the treatment of infectious and inflammatory diseases. Hereby, we present results of studies carried out according to the pharmacopoeia standards for the identification of herbal drugs, in the whole, fragmented, and powdered plant material. These results were complemented with scanning electron microscopy and histochemical techniques. The leaf microscopic analysis revealed a typical dorsiventral mesophyll with a corresponding spongy parenchyma-palisade parenchyma ratio of 0.60, anomocytic and paracytic stomata, papillate cells with a diameter of 4.00 ± 0.40 µm, multicellular uniseriate nonglandular trichomes with a length of 27.00 ± 4.10 µm and cristalliferous idioblasts containing calcium oxalate cluster crystals with a diameter of 23.04 ± 5.84 µm. The present findings demonstrate that the G. arenicola leaf has both nonglandular trichomes and hypoderm, features not previously described in the corresponding botanical section (Gymnosporia sect. Buxifoliae Jordaan). The establishment of these new botanical markers for the identification of G. arenicola leaf is essential for quality, safety and efficacy reasons.


Assuntos
Celastraceae/anatomia & histologia , Celastraceae/citologia , Plantas Medicinais/anatomia & histologia , Plantas Medicinais/citologia , Histocitoquímica , Microscopia , Moçambique , Folhas de Planta/anatomia & histologia , Folhas de Planta/citologia , África do Sul
9.
Fitoterapia ; 106: 7-11, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26241493

RESUMO

The isolation and structural elucidation of a macrocyclic alkaloid, characterized by the presence of a 13-membered macrolactam ring containing a spermidine unit N-linked to a benzoyl group is hereby reported. The structure of this previously unknown spermidine alkaloid isolated from Gymnosporia arenicola (Celastraceae) leaves has been elucidated by (1)H and (13)C NMR spectroscopy (including bidimensional analysis) and further characterized by high-resolution mass spectrometry and polarimetry. A route for the biosynthesis of this new bioactive macrocycle is proposed and the cytotoxicity of the compound was evaluated against two ATCC cell lines - one normal-derived (MCF10A) and one cancer-derived cell line (MCF7) - using the MTT assay. The alkaloid revealed to be non-cytotoxic against both cell lines. The IC50 values from the cells were also determined.


Assuntos
Alcaloides/química , Celastraceae/química , Folhas de Planta/química , Espermidina/química , Alcaloides/isolamento & purificação , Linhagem Celular , Humanos , Estrutura Molecular , Espermidina/isolamento & purificação
10.
FEMS Microbiol Lett ; 211(2): 203-6, 2002 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-12076813

RESUMO

We used the agar dilution method to evaluate the antibacterial effect of Terminalia macroptera leaf (Tml) extract against nine reference and clinical Neisseria gonorrhoeae strains, including penicillin- and tetracycline-resistant and -susceptible strains. Tml possesses anti-N. gonorrhoeae activity against all of the strains and the minimum inhibitory concentrations (MIC) were between 100 and 200 microg ml(-1). We then used a liquid-liquid partition method to divide the Tml extract into five fractions and determined the anti-N. gonorrhoeae activity of each of the fractions. All of the fractions showed antibacterial activity. The most active one was identified as the diethyl ether fraction and had MIC values of between 25 and 50 microg ml(-1) against all of the strains.


Assuntos
Antibacterianos/farmacologia , Taninos Hidrolisáveis , Luteolina , Neisseria gonorrhoeae/efeitos dos fármacos , Terminalia , Benzopiranos/química , Ácido Elágico/química , Flavonoides/química , Ácido Gálico/química , Glucosídeos/química , Neisseria gonorrhoeae/crescimento & desenvolvimento , Extratos Vegetais/farmacologia , Folhas de Planta/química , Taninos/química , Terminalia/química
11.
FEMS Microbiol Lett ; 217(2): 271-4, 2002 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-12480115

RESUMO

We used the agar dilution method to evaluate the antibacterial effect of Terminalia macroptera leaf (Tml) extract against nine reference and clinical Neisseria gonorrhoeae strains, including penicillin- and tetracycline-resistant and -susceptible strains. Tml possesses anti-N. gonorrhoeae activity against all of the strains and the minimum inhibitory concentrations (MIC) were between 100 and 200 microg ml(-1). We then used a liquid-liquid partition method to divide the Tml extract into five fractions and determined the anti-N. gonorrhoeae activity of each of the fractions. All of the fractions showed antibacterial activity. The most active one was identified as the diethyl ether fraction and had MIC values of between 25 and 50 microg ml(-1) against all of the strains.


Assuntos
Antibacterianos/farmacologia , Neisseria gonorrhoeae/efeitos dos fármacos , Terminalia/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Fatores Inibidores da Migração de Macrófagos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/metabolismo , Extratos Vegetais/farmacologia , Folhas de Planta/química , Raízes de Plantas/química , Terminalia/classificação , Terminalia/metabolismo
12.
Fitoterapia ; 83(5): 872-6, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22465506

RESUMO

The root of Terminalia macroptera Guill. & Perr. (Combretaceae) is widely used in African traditional medicine to treat various infectious diseases, including stomach-associated diseases. This study investigates the in vitro activity of T. macroptera root extract against reference strains and clinical isolates of H. pylori and attempts to localize the extract bioactivity. T. macroptera hydroethanol (80% V/V) root extract (Tmr) activity was tested against three standard strains and sixty two clinical strains of H. pylori. Tmr liquid-liquid partition fractions were screened against twenty H. pylori strains. Qualitative analysis of Tmr and its fractions was performed by HPLC-UV/DAD. The antibiotic characterization of the H. pylori strains revealed that 20% of the tested clinical isolates were resistant to at least two of the three antibiotics belonging to the main groups of antibiotics used in multi-therapy to eradicate H. pylori infections. In contrast, Tmr showed anti-H. pylori activity against the majority (92%) of the tested strains (MIC(50) and MIC(90)=200 µg/ml). The Tmr water liquid-liquid fraction (Tmr-3) and the precipitate obtained from this fraction (Tmr-5) were the most active tested samples, showing a MIC(50) of 100 µg/ml. The present work proves the in vitro activity of T. macroptera against H. pylori, thus confirming the utility of this traditional medicinal plant to treat stomach complaints due to H. pylori infection. The main compounds of Tmr and of Tmr-3 were the ellagitannins terchebulin and punicalagin. These compounds can be considered as markers of T. macroptera root active extracts against H. pylori.


Assuntos
Antibacterianos/farmacologia , Helicobacter pylori/efeitos dos fármacos , Taninos Hidrolisáveis/farmacologia , Extratos Vegetais/farmacologia , Pirrolidinonas/farmacologia , Terminalia/química , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Medicinas Tradicionais Africanas , Testes de Sensibilidade Microbiana , Raízes de Plantas/química , Pirrolidinonas/química , Pirrolidinonas/isolamento & purificação , Gastropatias/tratamento farmacológico , Gastropatias/microbiologia
13.
Microsc Microanal ; 14(5): 398-404, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18793484

RESUMO

Guiera senegalensis J. F. Gmel. (Combretaceae) is one of the most important West African medicinal plants, often used to treat a variety of microbial infections. The most frequently used plant part is the leaf, its medicinal use being corroborated by several in vitro antimicrobial activity studies. However, quality criteria for pharmaceutical use, including botanical identification, are not yet determined. Aiming the establishment of such criteria, the present work deepens today's knowledge on G. senegalensis leaf morphology and anatomy, the anatomical characters of both leaf transversal section and powdered leaves being hereby presented for the first time. The most useful characters for identification purposes are leaf isobilateral organization, with similar upper and lower surfaces and a palisade parenchyma on both surfaces; trichome insertion points on both epidermis, surrounded by polar arrangements of cells; tomentose indumentum on the upper epidermis consisting of compartmented and uniseriated trichomes with long, curved, or straight terminal cells; brown scales, isolated or inserted into the epidermis, formed by radially arranged cells surrounding a central cell, with a more or less circular form and a conspicuous base; calcium oxalate cluster crystals, isolated or inserted into the palisade parenchyma and absent in lateral veins.


Assuntos
Combretaceae/citologia , Plantas Medicinais/citologia , África , Combretaceae/ultraestrutura , Microscopia Eletrônica de Varredura , Folhas de Planta/citologia , Folhas de Planta/ultraestrutura , Plantas Medicinais/ultraestrutura
14.
J Nat Prod ; 66(3): 447-9, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12662113

RESUMO

A new methoxylated naphthyl butenone, guieranone A (1), was isolated from the leaves of Guiera senegalensis. Its structure was elucidated as (2E)-1-(1,3,6,8-tetramethoxy-2-naphthyl)but-2-en-1-one, on the basis of spectroscopic data. Also isolated were two known naphthopyrones, 5-methyldihydroflavasperone (2) and 5-methylflavasperone (3). Guieranone (1) exhibited potent antifungal activity against Cladosporium cucumerinum and is the first naphthyl ketone derivative to have been isolated from the family Combretaceae.


Assuntos
Antifúngicos/isolamento & purificação , Butanonas/isolamento & purificação , Cladosporium/efeitos dos fármacos , Combretaceae/química , Naftalenos/isolamento & purificação , Plantas Medicinais/química , Antifúngicos/química , Antifúngicos/farmacologia , Butanonas/química , Butanonas/farmacologia , Guiné , Medicinas Tradicionais Africanas , Estrutura Molecular , Naftalenos/química , Naftalenos/farmacologia , Folhas de Planta/química
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