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3.
J Appl Microbiol ; 120(1): 41-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26442997

RESUMO

AIM: The aim of this study was to investigate the in vitro and in vivo activities of pure curcumin, as well as its combination with fluconazole, against Cryptococcus gattii. METHODS AND RESULTS: The minimal inhibitory concentrations (MIC) of curcumin and its interactions with fluconazole against C. gattii were assessed in vitro using standard methods. This same combination was used to treat C. gattii-induced cryptococcosis in mice. The behavioural and functional assessment of the mice during treatment was also performed. The average MIC for curcumin was 19·8 µg ml(-1) . Its combination with fluconazole resulted in FICΣ (fractional inhibitory concentration index) values between 0·79 and 2·29. Curcumin (alone or combined with fluconazole) significantly reduced pulmonary damage and fungal burden in the brain. No colonies were found in the brain following combination treatment, which was also confirmed by the improved behaviour of mice. CONCLUSIONS: The combination therapy with curcumin and fluconazole was the most effective among the treatments tested, as in addition to reducing the fungal burden and damage on lung tissues, it was able to eliminate the fungal burden in the brain, enhancing the survival of mice. SIGNIFICANCE AND IMPACT OF THE STUDY: This study points to the possibility of using curcumin in combination with fluconazole as a clinical treatment of cryptococcosis.


Assuntos
Antifúngicos/administração & dosagem , Criptococose/tratamento farmacológico , Cryptococcus gattii/efeitos dos fármacos , Curcumina/administração & dosagem , Fluconazol/administração & dosagem , Animais , Criptococose/microbiologia , Cryptococcus gattii/crescimento & desenvolvimento , Sinergismo Farmacológico , Quimioterapia Combinada , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 3829-3834, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28269121

RESUMO

This paper describes a new method for recognizing hand configurations of the Brazilian Gesture Language - LIBRAS - using depth maps obtained with a Kinect® camera. The proposed method comprised three phases: hand segmentation, feature extraction, and classification. The segmentation phase is independent from the background and depends only on pixel depth information. Using geometric operations and numerical normalization, the feature extraction process was done independent from rotation and translation. The features are extracted employing two techniques: (2D)2LDA and (2D)2PCA. The classification is made with a novelty classifier. A robust database was constructed for classifier evaluation, with 12,200 images of LIBRAS and 200 gestures of each hand configuration. The best accuracy obtained was 95.41%, which was greater than previous values obtained in the literature.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Língua de Sinais , Adolescente , Adulto , Brasil , Bases de Dados Factuais , Feminino , Gestos , Mãos , Humanos , Idioma , Masculino , Adulto Jovem
5.
Ultrasound Obstet Gynecol ; 41(1): 90-4, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22461324

RESUMO

We report on four cases of fetal cervical tumor, comprising three lymphangiomas and one teratoma, evaluated by ultrasound and magnetic resonance imaging (MRI) between 26 and 37 weeks' gestation. The aim was to investigate the use of virtual bronchoscopy to evaluate fetal airway patency in each case. A three-dimensional (3D) model of the airway was created from overlapping image layers generated by MRI. The files obtained were manipulated using 3D modeling software, allowing the virtual positioning of observation cameras, adjustment of lighting parameters and creation of simulated 3D movies for analysis of a virtual path through the model. In all fetuses, fetal airway patency was clearly demonstrated by virtual bronchoscopy and this was confirmed postnatally. MRI with virtual bronchoscopy could become a useful tool for studying fetal airway patency in cases of cervical tumor.


Assuntos
Broncoscopia/métodos , Feto/patologia , Neoplasias de Cabeça e Pescoço/complicações , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Sistema Respiratório/patologia , Feminino , Doenças Fetais/patologia , Humanos , Linfangioma/complicações , Masculino , Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez , Teratoma/complicações
6.
Mater Sci Eng C Mater Biol Appl ; 32(6): 1588-93, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24364964

RESUMO

The search for bioactive molecules to be employed as recognition elements in biosensors has stimulated researchers to pore over the rich Brazilian biodiversity. In this sense, we introduce the use of natural cashew gum (Anacardium occidentale L.) as an active biomaterial to be used in the form of layer-by-layer films, in conjunction with phthalocyanines, which were tested as electrochemical sensors for dopamine detection. We investigated the effects of chemical composition of cashew gum from two different regions of Brazil (Piauí and Ceará states) on the physico-chemical characteristics of these nanostructures. The morphology of the nanostructures containing cashew gum was studied by atomic force microscopy which indicates that smooth films punctuated by globular features were formed that showed low roughness values. The results indicate that, independent of the origin, cashew gum stands out as an excellent film forming material with potential application in nanobiomedical devices as electrochemical sensors.


Assuntos
Anacardium/química , Materiais Biocompatíveis/química , Nanoestruturas/química , Técnicas Biossensoriais/métodos , Dopamina/química , Indóis/química , Isoindóis
8.
Lett Appl Microbiol ; 51(4): 469-76, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20840554

RESUMO

AIMS: To evaluate the antiviral activity of Bignoniaceae species occurring in the state of Minas Gerais, Brazil. METHODS AND RESULTS: Ethanol extracts of different anatomical parts of bignoniaceous plant species have been evaluated in vitro against human herpesvirus type 1 (HSV-1), vaccinia virus (VACV) and murine encephalomyocarditis virus (EMCV) by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. A total of 34 extracts from 18 plant species selected according to ethnopharmacological and taxonomic criteria were screened. Fifteen of the 34 extracts (44.1%) have disclosed antiviral activity against one or more of the viruses assayed with EC(50) values in the range of 23.2 ± 2.5-422.7 ± 10.9 µg ml(-1). CONCLUSIONS: Twelve of the 34 extracts (35.3%) might be considered promising sources of antiviral natural products, as they have shown EC50 ≤ 100 µg ml(-1). The present screening discloses the high potential of the Bignoniaceae family as source of antiviral agents. SIGNIFICANCE AND IMPACT OF THE STUDY: Active extracts were identified and deserve bioguided studies for the isolation of antiviral compounds and studies on mechanism of action.


Assuntos
Antivirais/farmacologia , Bignoniaceae/química , Vírus da Encefalomiocardite/efeitos dos fármacos , Herpesvirus Humano 1/efeitos dos fármacos , Extratos Vegetais/farmacologia , Vaccinia virus/efeitos dos fármacos , Animais , Bignoniaceae/classificação , Brasil , Chlorocebus aethiops , Humanos , Células L , Camundongos , Testes de Sensibilidade Microbiana/métodos , Extratos Vegetais/química , Células Vero
9.
Ultrasound Obstet Gynecol ; 36(3): 355-61, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20205157

RESUMO

OBJECTIVE: To generate physical fetal models using images obtained by three-dimensional ultrasonography (3DUS), magnetic resonance imaging (MRI) and computed tomography (CT) to guide additive manufacturing technology. METHODS: Images from 33 fetuses, including three sets of twins, were used. Fifteen fetuses were normal and evaluated only by 3DUS. Eighteen cases had abnormalities such as conjoined twins, tumors, aneuploidy, skeletal abnormalities, central nervous system abnormalities and facial or thoracic defects. Scans were performed using high-resolution 3DUS. In cases of abnormalities, MRI and CT were performed on the same day as 3DUS. The images obtained with 3DUS, CT or MRI were exported to a workstation in DICOM format. A single observer performed slice-by-slice manual segmentation using a digital high-definition screen. Software that converts medical images into numerical models was used to construct virtual 3D models, which were physically realized using additive manufacturing technologies. RESULTS: Physical models based on 3DUS, MRI and CT images either separately or combined were successfully generated. They were remarkably similar to the postnatal appearance of the aborted fetus or newborn baby, especially in cases with pathology. CONCLUSION: The use of 3DUS, MRI and CT may improve our understanding of fetal anatomical characteristics, and these technologies can be used for educational purposes and as a method for parents to visualize their unborn baby. The images can be segmented and applied separately or combined to construct 3D virtual and physical models.


Assuntos
Feto/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Modelos Anatômicos , Feminino , Humanos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Gravidez , Tomografia Computadorizada por Raios X/métodos
10.
Transplant Proc ; 41(3): 859-61, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19376372

RESUMO

BACKGROUND: Prospective testing for posttransplant circulating anti-HLA antibodies seems to be a critical noninvasive tool, but confirmatory data are lacking. MATERIALS AND METHODS: Over the last 3 years, peritubular capillary (PTC) C4d deposition was prospectively sought by an immunofluorescence technique applied to frozen tissue in biopsies obtained for allograft dysfunction. Screening for circulating anti-HLA class I/II alloantibodies (AlloAb) by the flow cytometric test was performed simultaneously. RESULTS: We evaluated 132 sets of biopsies and simultaneous serum samples. PTC C4d deposition was demonstrated in 15.9% (21/132) of biopsies. Circulating anti-HLA I/II AlloAb were detected in 25% (33/132) of serum samples. Employing receiver-operator characteristic (ROC) curves for all C4d-positive biopsies, screening for AlloAb showed a global specificity of 82% and sensitivity of 61.9%. When this analysis was restricted to biopsies obtained in the first month posttransplantation, the sensitivity increased to 81.8%, but the specificity decreased to 76.9%. After the first month posttransplantation, we observed sensitivity of 40.0% and a specificity of 86.4%. In the first month posttransplantation, all patients with a diagnosis of acute antibody-mediated rejection displayed circulating anti-HLA class I/II, but not always at the same time as the C4d-positive biopsy. CONCLUSIONS: In the first month posttransplantation, prospective monitoring of anti-HLA antibodies may be useful. The high sensitivity allows the identification of patients at risk, affording an earlier diagnosis of antibody-mediated rejection. After the first month, the test can be used to evaluate allograft dysfunction episodes, since positivity is highly suggestive of an antibody-mediated process.


Assuntos
Antígenos HLA/imunologia , Isoanticorpos/sangue , Transplante de Rim/patologia , Transplante Homólogo/patologia , Adulto , Biomarcadores/sangue , Biópsia , Complemento C4b/análise , Feminino , Citometria de Fluxo , Antígenos HLA-D/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Humanos , Transplante de Rim/imunologia , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/análise , Reoperação/estatística & dados numéricos , Sensibilidade e Especificidade , Transplante Homólogo/imunologia
12.
Virus Genes ; 23(3): 291-301, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11778697

RESUMO

The lack of knowledge about the natural host of Vaccinia virus (VV) along with the description of human infections caused by poxviruses after smallpox eradication has increased the need to characterize poxviruses isolated from the wild. Moreover, in the past years poxviruses have been widely studied as potential vaccination tools, with the discovery of several genes implicated in the evasion of the host immune response involved in virus pathogenesis. Among them, an Interferon (IFN)-binding protein was identified in the supernatant of VV strain WR infected cells coded by the B18R gene. It was shown that many other Orthopoxviruses also encode and express this soluble receptor although some VV strains such as Lister and modified Ankara, which were less reactogenic vaccines, do not. The BeAn 58058 virus (BAV) has been recently characterized and proposed to be an Orthopoxvirus. BAV was also shown to be less virulent in animal models than VV Lister. Here we report the identification of an IFN-alpha/betaR gene in the BAV genome with 99% of sequence identity with the VVWR B18R gene. The identified gene encodes a B18R-like IFN binding protein as demonstrated by its capacity to inhibit the IFN-mediated protection of VERO cells against EMC virus. In order to better characterize the virus we have searched for the A type inclusion body (ATI) gene currently used in the classification of Orthopoxviruses but did not detect it in the BAV genome. We have also sequenced the BAV thymidine kinase (TK) gene, a poxvirus-conserved gene, which, as expected, showed high homology with the TK gene of other poxviruses. Phylogenetic trees were constructed based on sequences of the IFN-alpha/betaR and TK genes from several poxviruses and in both cases BAV was placed in the same cluster as other VV strains. These observations strengthened the hypothesis that this virus is a variant of the VV vaccine used in Brazil. However the explanation for the BAV lack of virulence remains to be discovered.


Assuntos
Orthopoxvirus/genética , Receptores de Interferon/genética , Timidina Quinase/genética , Proteínas Virais/genética , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/imunologia , Sequência de Bases , Chlorocebus aethiops , DNA Viral , Genoma Viral , Corpos de Inclusão Viral/genética , Interferons/antagonistas & inibidores , Proteínas de Membrana , Dados de Sequência Molecular , Testes de Neutralização , Orthopoxvirus/imunologia , Orthopoxvirus/patogenicidade , Receptor de Interferon alfa e beta , Receptores de Interferon/química , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Células Vero , Proteínas Virais/química
13.
Braz J Med Biol Res ; 30(11): 1371-6, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9532249

RESUMO

In awake rats a single recurrent larger tidal volume (deep breaths) occurs at regular intervals, followed by oscillations in arterial pressure and heart rate. In the present study we recorded the changes in blood pressure, heart rate and ventilation during the wakefulness-sleep cycle identified by electrocorticographic records in order to determine whether the deep breaths and cardiovascular oscillations were associated with changes in the electrocorticogram. During several episodes of slow-wave sleep (SWS) in 7 rats the deep breaths and oscillations in arterial pressure and heart rate were preceded by SWS desynchronization. The interval between deep breaths during SWS was 71 +/- 4 s, the period between initial desynchronization and the generation of deep breaths was 3.98 +/- 0.45 s and the duration of SWS desynchronization was 11 +/- 0.65 s. Hypotension (-16 +/- 1 mmHg) and tachycardia (+15 +/- 5 bpm) were observed during deep breaths in the SWS state. These data indicate that the oscillations in arterial pressure and heart rate during SWS are associated with deep breaths, which in turn are preceded by desynchronization of the electrocorticogram in this state of sleep.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Sincronização Cortical , Fenômenos Fisiológicos Respiratórios , Fases do Sono/fisiologia , Animais , Masculino , Ratos , Ratos Wistar
14.
Braz J Med Biol Res ; 24(1): 21-7, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1726650

RESUMO

1. The molecular weight and the electrofocusing profile of human amniotic membrane interferon (IFN-AM) were determined. 2. When submitted to gel filtration, IFN-AM showed a single 26-28 kDa component; in polyacrylamide gel electrophoresis one component of 19,500. 3. In electrofocusing, IFN-AM displayed a heterogeneous profile with 5 to 7 peaks, but different from human alpha or beta IFNs. This heterogeneity was reduced by previous treatment of IFN-AM with neuraminidase. 4. IFN-AM is a sialoglycoprotein similar to human beta IFN in terms of antigenicity but different from it in electrofocusing profile.


Assuntos
Membranas Extraembrionárias/metabolismo , Interferons/química , Placenta/química , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Humanos , Focalização Isoelétrica , Peso Molecular
15.
J Interferon Res ; 9(5): 573-81, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2477473

RESUMO

The presence of protein(s) with interferon (IFN)-like activity in culture fluid from human amniotic membranes induced by viruses has been described by different groups. However, the antigenic structure of this protein is controversial. Here we report the presence of IFN activity in supernatants of human amniotic membranes induced by Sendai virus. The major component responsible for this antiviral activity seems to be the classical IFN-beta. However, we were able to demonstrate the presence of a protein fraction with antiviral activity that does not bind to an affinity column for IFN-beta. The antiviral activity of this unbound fraction cannot be neutralized by antibodies to IFN-alpha, -beta, gamma, or by a mixture of them. We called this unbound fraction IFN-AM. We also report the development of a monoclonal antibody that does not neutralize the antiviral activity of IFN-alpha or IFN-beta but reduces the antiviral activity of a partially purified preparation of Sendai virus-induced amniotic membrane supernatant. These observations suggest that the IFN-AM (the unbound fraction that lacks reactivity with antibodies against known IFNs) contains a unique antigenic determinant that is not present, or, if so, is not located at the functional domain of IFN-alpha, -beta, or -gamma.


Assuntos
Âmnio/imunologia , Epitopos/imunologia , Interferons/imunologia , Anticorpos Monoclonais/imunologia , Humanos , Interferons/biossíntese , Interferons/classificação , Vírus da Parainfluenza 1 Humana/imunologia
16.
An Acad Bras Cienc ; 56(2): 221-30, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6385793

RESUMO

By applying various histological techniques the results obtained were similar to those in Lacombe's previous publications referring to the development of Trypanosoma cruzi in haemolymph, the later penetration in the Malpighian tubes and their return to the digestive tract. Trypomastigotes and sphaeromastigotes are found in the promesenteron after two hours of feeding the insect with mice blood containing numerous Trypanosoma cruzi. Some parasites move to the promesenteron from postmesenteron and others from the haemolymph of the insect. The amastigotes form inside the haemocytes, multiply, occupying nearly all the cells of the haemolymph. The parasites liberated inside the Malpighian tubes move to the ampullae where they begin their growth. The parasites in epimastigote and trypomastigote forms cross the pyloric valve and adhere to the folds of the rectum.


Assuntos
Cloaca/parasitologia , Hemolinfa/parasitologia , Túbulos de Malpighi/parasitologia , Panstrongylus/parasitologia , Triatoma/parasitologia , Triatominae/parasitologia , Trypanosoma cruzi/crescimento & desenvolvimento , Animais , Piloro/parasitologia , Reto/parasitologia
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