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1.
Comput Biol Med ; 115: 103516, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31707199

RESUMO

Treatment selection is becoming increasingly more important in acute ischemic stroke patient care. Clinical variables and radiological image biomarkers (old age, pre-stroke mRS, NIHSS, occlusion location, ASPECTS, among others) have an important role in treatment selection and prognosis. Radiological biomarkers require expert annotation and are subject to inter-observer variability. Recently, Deep Learning has been introduced to reproduce these radiological image biomarkers. Instead of reproducing these biomarkers, in this work, we investigated Deep Learning techniques for building models to directly predict good reperfusion after endovascular treatment (EVT) and good functional outcome using CT angiography images. These models do not require image annotation and are fast to compute. We compare the Deep Learning models to Machine Learning models using traditional radiological image biomarkers. We explored Residual Neural Network (ResNet) architectures, adapted them with Structured Receptive Fields (RFNN) and auto-encoders (AE) for network weight initialization. We further included model visualization techniques to provide insight into the network's decision-making process. We applied the methods on the MR CLEAN Registry dataset with 1301 patients. The Deep Learning models outperformed the models using traditional radiological image biomarkers in three out of four cross-validation folds for functional outcome (average AUC of 0.71) and for all folds for reperfusion (average AUC of 0.65). Model visualization showed that the arteries were relevant features for functional outcome prediction. The best results were obtained for the ResNet models with RFNN. Auto-encoder initialization often improved the results. We concluded that, in our dataset, automated image analysis with Deep Learning methods outperforms radiological image biomarkers for stroke outcome prediction and has the potential to improve treatment selection.


Assuntos
Isquemia Encefálica , Angiografia Cerebral , Angiografia por Tomografia Computadorizada , Procedimentos Endovasculares/efeitos adversos , Redes Neurais de Computação , Complicações Pós-Operatórias/diagnóstico por imagem , Sistema de Registros , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Acidente Vascular Cerebral/etiologia
2.
J Med Chem ; 59(20): 9350-9369, 2016 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-27690420

RESUMO

Aminoglycosides (AGs) constitute a major family of potent and broad-spectrum antibiotics disturbing protein synthesis through binding to the A site of 16S rRNA. Decades of widespread clinical use of AGs strongly reduced their clinical efficacy through the selection of resistant bacteria. Recently, conjugation of lipophilic groups to AGs generated a novel class of potent antibacterial amphiphilic aminoglycosides (AAGs) with significant improved activities against various sensitive and resistant bacterial strains. We have identified amphiphilic 3',6-dialkyl derivatives of the small aminoglycoside neamine as broad spectrum antibacterial agents targeting bacterial membranes. Here, we report on the synthesis and the activity against sensitive and resistant Gram-negative and/or Gram-positive bacteria of new amphiphilic 3',4'-dialkyl neamine derivatives and of their smaller analogues in the 6-aminoglucosamine (neosamine) series prepared from N-acetylglucosamine.


Assuntos
Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Framicetina/química , Framicetina/farmacologia , Glucosamina/análogos & derivados , Tensoativos/farmacologia , Aminoglicosídeos/síntese química , Aminoglicosídeos/química , Antibacterianos/síntese química , Antibacterianos/química , Relação Dose-Resposta a Droga , Framicetina/síntese química , Glucosamina/síntese química , Glucosamina/química , Glucosamina/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Tensoativos/síntese química , Tensoativos/química
3.
Vet Parasitol ; 167(1): 1-7, 2010 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-19896276

RESUMO

The chemical composition of essential oils from three species of plants belonging to the Eucalyptus genus was determined and, their insecticidal effects on egg, larva and adult phases of Lutzomyia longipalpis were assessed. The insects were collected in the municipality of Sobral in the State of Ceará, Brazil. Five treatments with different concentrations were performed along with two negative controls, distilled water and Tween 80 (3%), and a positive control, cypermethrin (0.196mg/ml). The tests were carried out in plastic pots internally coated with sterile plaster and filled with a substrate made of rabbit feces and crushed cassava leaves. The eggs, larvae and adults were sprayed with the oils. The hatched larvae were counted for 10 consecutive days and observed until pupation. Insect mortality was observed after 24, 48 and 72h. E. staigeriana oil was the most effective on all three phases of the insect, followed by E. citriodora and E. globulus oils, respectively. The major constituents of the oils were Z-citral and alpha-citral (E. staigeriana), citronellal (E. citriodora) and 1,8-cineole (E. globulus). The Eucalyptus essential oils constitute alternative natural products for the control of L. longipalpis since the median effective concentration (EC(50)) values revealed relevant action as compared with other natural products, some of their chemical constituents are already known for their insecticidal activity and these oils are produced in commercial scale in Brazil.


Assuntos
Eucalyptus/química , Insetos Vetores/crescimento & desenvolvimento , Monoterpenos/farmacologia , Controle Biológico de Vetores/métodos , Óleos de Plantas/farmacologia , Psychodidae/crescimento & desenvolvimento , Animais , Brasil , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Larva/crescimento & desenvolvimento
4.
Vet Parasitol ; 159(1): 55-9, 2009 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-19042088

RESUMO

The development of anthelmintic resistance has made the search for alternatives to control gastrointestinal nematodes of small ruminants imperative. Among these alternatives are several medicinal plants traditionally used as anthelmintics. This work evaluated the efficacy of Cocos nucifera fruit on sheep gastrointestinal parasites. The ethyl acetate extract obtained from the liquid of green coconut husk fiber (LGCHF) was submitted to in vitro and in vivo tests. The in vitro assay was based on egg hatching (EHT) and larval development tests (LDT) with Haemonchus contortus. The concentrations tested in the EHT were 0.31, 0.62, 1.25, 2.5 and 5 mg ml(-1), while in the LDT they were 5, 10, 20, 40 and 80 mg ml(-1). The in vivo assay was a controlled test. In this experiment, 18 sheep infected with gastrointestinal nematodes were divided into three groups (n=6), with the following doses administered: G1-400 mg kg(-1) LGCHF ethyl acetate extract, G2-0.2 mg kg(-1) moxidectin (Cydectin) and G3-3% DMSO. The worm burden was analyzed. The results of the in vitro and in vivo tests were submitted to ANOVA and analyzed by the Tukey and Kruskal-Wallis tests, respectively. The extract efficacy in the EHT and LDT, at the highest concentrations tested, was 100% on egg hatching and 99.77% on larval development. The parameters evaluated in the controlled test were not statistically different, showing that despite the significant results of the in vitro tests, the LGCHF ethyl acetate extract showed no activity against sheep gastrointestinal nematodes.


Assuntos
Anti-Helmínticos/farmacologia , Cocos/química , Hemoncose/tratamento farmacológico , Haemonchus/efeitos dos fármacos , Fitoterapia/veterinária , Extratos Vegetais/farmacologia , Doenças dos Ovinos/tratamento farmacológico , Análise de Variância , Animais , Anti-Helmínticos/uso terapêutico , Relação Dose-Resposta a Droga , Hemoncose/parasitologia , Hemoncose/veterinária , Haemonchus/crescimento & desenvolvimento , Enteropatias Parasitárias/tratamento farmacológico , Enteropatias Parasitárias/veterinária , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Contagem de Ovos de Parasitas/veterinária , Testes de Sensibilidade Parasitária , Extratos Vegetais/uso terapêutico , Plantas Medicinais/química , Ovinos , Doenças dos Ovinos/parasitologia , Estatísticas não Paramétricas
5.
Vet Parasitol ; 155(1-2): 24-31, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18565676

RESUMO

Visceral leishmaniasis (VL) is one of the most important reemerging parasitic disease in the world. The domestic dog is the main reservoir in urban environments. The aim of this work was to extend the knowledge on canine Leishmania infection in the city of Fortaleza in northeastern Brazil, identifying the risk factors inherent in dog susceptibility to the infection. Two populations were analyzed, domestic dogs from clinics and the Veterinary Hospital Unit of Ceará State University and stray dogs captured by the Center for Zoonosis Control in Fortaleza. Blood samples were collected and centrifuged and the sera were stored at -20 degrees C. ELISA, with soluble crude Leishmania chagasi antigens (LTCC - WDCM731) was used for diagnosis. A total of 1,381 samples were tested, 750 from domestic and 631 from stray dogs. The seroprevalence of canine VL was 21.4% (135/631) in stray dogs and 26.2% (197/750) in domestic dogs. The seroprevalence of Leishmania infection in the six administrative regions of the city (Secretarias Executivas Regionais, or SER) among stray dogs was highest in SER V, representing 31.4% of the cases, with large dogs more infected (27.7%). Among domestic dogs Leishmania infection was most prevalent in SER V (38.5%) and VI (37.6%). The dogs' age (1-6 years), large size, environment with dense vegetation and presence of clinical signs compatible with Leishmania infection were associated with the illness in domestic dogs. The frequency of the infection varied seasonally. The seroprevalence was greatest in July and December. These results confirm Fortaleza is an endemic area for canine VL and suggest some variables associated with increasing infection risk in dog populations.


Assuntos
Doenças do Cão/epidemiologia , Leishmaniose Visceral/veterinária , Animais , Brasil/epidemiologia , Estudos Transversais , Doenças do Cão/sangue , Doenças do Cão/parasitologia , Cães , Feminino , Leishmaniose Visceral/sangue , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/parasitologia , Masculino , Estudos Soroepidemiológicos , Fatores de Tempo
6.
Int J Addict ; 29(8): 1045-56, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7960299

RESUMO

Drug usage in a sample of 1,069 college students of São Paulo, Brazil, was investigated. The highest lifetime prevalence was reported for alcohol (82%) and tobacco (39%) followed by inhalants (28%), marijuana (26%), over-the-counter tranquilizers and stimulants (17%), and cocaine (10%). Current use is considerably smaller. Marijuana users were classified as having a "Stable," "Descending," and "Once" pattern of consumption frequency. These patterns were orderly related to sex, socioeconomic status, use of drugs, drug approval, and peer group. Drug usage appeared as predominantly social-recreational in this population, although the risk of misuse for "Stable" students should be evaluated.


Assuntos
Cocaína , Dietilamida do Ácido Lisérgico , Abuso de Maconha/epidemiologia , Mescalina , Entorpecentes , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adolescente , Adulto , Fatores Etários , Brasil/epidemiologia , Escolaridade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Fatores Socioeconômicos
7.
Radiol. bras ; 24(1): 137-40, jan.-mar. 1991. tab
Artigo em Português | LILACS | ID: lil-100040

RESUMO

O crescimento dos ossos metacarpais da mäo direita de 50 fetos humanos foi estudado com base em 3 mensuraçöes: comprimento total (CT), comprimento da diáfise ossificada (CO), e a largura da parte média do ossso (LM). A equaçäo Y=aXb (método alométrico) foi usada para ajustar os dados, sendo que x correspondeu à idade gestacional e Y às medidas metacarpais. Estas crescem com coeficiente alométrico b positivo. O crescimento de CO mostrou os maiores valores de b, e a velocidade de crescimento de LM foi mais intensa que a de CT. As equaçöes de crescimento dos ossos metacarpais e seus respectivos gráficos säo parâmetros quantitativos importantes, atualmente, para o diagnóstico pré-natal de deformidades congênitas da mäo, pela primeira vez determinados na populaçäo brasileira


Assuntos
Humanos , Gravidez , Masculino , Feminino , Desenvolvimento Ósseo/classificação , Desenvolvimento Fetal/classificação , Metacarpo/crescimento & desenvolvimento , Brasil
8.
Drug Alcohol Depend ; 23(2): 159-64, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2702926

RESUMO

Changes in frequency of marihuana smoking over time were investigated by interviewing forty-seven Brazilian students from São Paulo between 18 and 24 years old, of both sexes. From their report, it was concluded that the course of smoking frequency follows two predominant patterns. In one of them, the 'Stable Pattern', subjects report increasing consumption up to a peak frequency where they remain for a relatively long and stable period of time. In the other one, the 'Descending Pattern', subjects report a gradual increase up to a peak, followed by a clear decline in rate of use. Two other patterns were also detected in a small number of subjects. The diversity of patterns identified stresses the difficulty in predicting the course of marihuana smoking frequency by young people. The relationship between marihuana smoking and the use of other drugs was also investigated. The only drugs that were reported to be regularly consumed by the majority of subjects were alcohol and tobacco, while 90% of the subjects reported having tried at least one other illegal drug.


Assuntos
Fumar Maconha/epidemiologia , Estudantes , Adulto , Consumo de Bebidas Alcoólicas , Brasil , Feminino , Humanos , Masculino , Psicotrópicos , Fumar/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia
9.
Surg Radiol Anat ; 11(1): 49-52, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2497534

RESUMO

Twenty right metacarpal bones of Brazilian fetuses (ranging from 17 to 35 weeks post-conception) were studied by the allometric method to define the pattern of metacarpal growth. The metacarpal measurements analysed were their maximum length (ML), ossified shaft length (OSL) and midshaft breadth (MSB). These data were related to crown-rump length and the metacarpal weight to fetal weight. The increase in metacarpal measurements showed an allometric positive coefficient (kappa), highest in the OSL. The ML growth followed an axo-marginal pattern. The 3rd metacarpal showed the highest MSB kappa coefficient. The metacarpal weight showed the highest correlation coefficient (r) to the fetal data. These findings are important to the knowledge of human hand growth and are the basis of preventive surgery for congenital deformities of the hand.


Assuntos
Desenvolvimento Embrionário e Fetal , Deformidades Congênitas da Mão/cirurgia , Metacarpo/embriologia , Antropometria , Deformidades Congênitas da Mão/prevenção & controle , Humanos , Metacarpo/anatomia & histologia
10.
Planta ; 168(4): 530-5, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24232330

RESUMO

Aseptically cultured lateral buds of Salix viminalis L. collected from field-grown trees exhibited a clear periodicity in their ability to respond to exogenous abscisic acid (ABA). Buds were kept unopened by ABA only when the plants were dormant or entering dormancy. Short days alone did not induce bud dormancy in potted plants but ABA treatment following exposure to an 8-h photoperiod prevented bud opening although ABA treatment of buds from long-day plants did not. Naturally dormant buds taken from shoots of field-grown trees and cultured in the presence of ABA opened following a chilling treatment. In no cases were the induction and breaking of dormancy and response to ABA correlated with endogenous ABA levels in the buds.

11.
Arq. bras. neurocir ; 3(4): 245-7, 1984.
Artigo em Português | LILACS | ID: lil-24832

RESUMO

Relato do encontro de pseudo-aneurisma em anastomose temporocortical realizada em paciente com trombose de carotida interna e quadro clinico de isquemia transitoria.Pelo que sabemos, este e o terceiro caso relatado desta complicacao


Assuntos
Pessoa de Meia-Idade , Humanos , Masculino , Derivação Arteriovenosa Cirúrgica , Aneurisma Intracraniano , Complicações Pós-Operatórias
12.
Plant Physiol ; 63(4): 774-7, 1979 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16660810

RESUMO

A series of growth room experiments was carried out aiming to establish the role of abscisic acid on dormancy of Salix viminalis L. The inhibitor content and abscisic acid levels of extracts from roots, sap, leaves, and apical tissues of willow were measured using biological assay and gas-liquid chromatography.No evidence was obtained that photoperiodically mediated dormancy is associated with changes in abscisic acid levels or beta-inhibitor activity.

13.
Arq Neuropsiquiatr ; 36(2): 155-9, 1978 Jun.
Artigo em Português | MEDLINE | ID: mdl-655901

RESUMO

A case of giant aneurysm of the middle artery with the size of 12,0 x 8,0 x 6,0 cm is reported. Some aspects of the treatment of such aneurysm are considered. As far as we know this is the largest intracranial aneurysm ever recorded.


Assuntos
Aneurisma Intracraniano/cirurgia , Adulto , Angiografia Cerebral , Humanos , Aneurisma Intracraniano/patologia , Masculino , Complicações Pós-Operatórias , Crânio/diagnóstico por imagem
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