Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Ricardo Villar Barbosa de Oliveira is active.

Publication


Featured researches published by Ricardo Villar Barbosa de Oliveira.


Molecules | 2015

Antimicrobial and Seasonal Evaluation of the Carvacrol-Chemotype Oil from Lippia origanoides Kunth.

Sandra Sarrazin; Leomara da Silva; Ana de Assunção; Ricardo Villar Barbosa de Oliveira; Victor Calao; Rodrigo da Silva; Elena E. Stashenko; José Maria Ayres Maia; Rosa Helena Veras Mourão

This study evaluated the influence of seasonal variation on the yield and composition of essential oil of Lippia origanoides occurring in the Middle Rio Amazonas, Brazil, and the impact on its antimicrobial potential. The average oil yield was 1.7% ± 0.2% in the rainy season and 1.6% ± 0.3% in the dry season. Some correlations with climatic parameters were observed. The major components were carvacrol (rainy, 43.5% ± 1.9%; dry, 41.4% ± 2.04%), thymol (rainy, 10.7% ± 1.1%; dry, 10.6% ± 0.9%), p-cymene (rainy, 9.8% ± 0.7%; dry, 10.0% ± 1.4%) and p-methoxythymol (rainy, 9.6% ± 0.8%; dry, 10.4% ± 1.4%). It was found that the antibacterial activity of L. origanoides against Staphylococcus aureus and Escherichia coli was little influenced by the changes in oil composition due to seasonal variation. Against S. aureus, the oil Minimum Inhibitory Concentration (MIC) value was 1.25 μL/mL over ten months. Against E. coli, the oil MIC values ranged from 0.15 μL/mL to 0.31 μL/mL in different months of the year. The Minimum Bactericidal Concentration (MBC) value was 2.5 μL/mL against S. aureus and 1.25 μL/mL against E. coli. The results suggest that the antimicrobial activity identified in the oil remain unchanged for the full year, allowing its medicinal use without any risk of loss or absence of the active principles of the plant.


Clinics | 2014

Risk factors associated with death in Brazilian children with severe dengue: a case-control study

Maria dos Remedios Freitas Carvalho Branco; Expedito José de Albuquerque Luna; Leônidas Lopes Braga Júnior; Ricardo Villar Barbosa de Oliveira; Lívia Teresa Moreira Rios; Maria do Socorro da Silva; Maria Nilza Lima Medeiros; Gilnara Fontinelle Silva; Fernanda Campos Amaral Figueiredo Nina; Taliane Jardim Lima; Jayron Alves Brito; Avessandra Costa Cardoso de Oliveira; Cláudio Sérgio Pannuti

OBJECTIVE: The purpose of this case-control study was to evaluate risk factors associated with death in children with severe dengue. METHODS: The clinical condition of hospitalized patients with severe dengue who died (cases, n = 18) was compared with that of hospitalized patients with severe dengue who survived (controls, n = 77). The inclusion criteria for this study were age under 13 years; hospital admission in São Luis, northeastern Brazil; and laboratory-confirmed diagnosis of dengue. RESULTS: Severe bleeding (hemoptysis), a defining criterion for dengue severity, was the factor most strongly associated with death in our study. We also found that epistaxis and persistent vomiting, both included as warning signs in the World Health Organization (WHO) classification of dengue, were strongly associated with death. No significant association was observed between any of the laboratory findings and death. CONCLUSIONS: The finding that epistaxis and persistent vomiting were also associated with death in children with severe dengue was unexpected and deserves to be explored in future studies. Because intensive care units are often limited in resource-poor settings, any information that can help to distinguish patients with severe dengue with a higher risk to progress to death may be crucial.


Radiologia Brasileira | 2010

Anormalidades do primeiro trimestre da gravidez: ensaio iconográfico

Lívia Teresa Moreira Rios; Ricardo Villar Barbosa de Oliveira; Marília da Glória Martins; Kemuel Pinto Bandeira; Olga Maria Ribeiro Leitão; Graciete Helena Nascimento dos Santos; Márcia da Silva Sousa

As anormalidades do primeiro trimestre da gravidez sao detectadas pela ultrassonografia transvaginal em exame de rotina ou em caso de sangramento vaginal anormal. A ameaca de abortamento e uma afeccao comum no primeiro trimestre da gestacao, ocorrendo em mais de um terco dos casos. O advento de sondas vaginais de alta resolucao vem revolucionando nossa compreensao da fisiopatologia e o manejo da gestacao inicial. Trata-se de ferramenta essencial para determinar a viabilidade da gestacao nos casos de ameaca de abortamento. Uma conduta expectante no abortamento poderia reduzir significativamente o numero de esvaziamentos desnecessarios de produtos retidos, dependendo dos criterios utilizados.


Radiologia Brasileira | 2010

Valor da ultrassonografia em crianças com suspeita de febre hemorrágica do dengue: revisão da literatura

Ricardo Villar Barbosa de Oliveira; Lívia Teresa Moreira Rios; Maria dos Remédios Freitas Carvalho Branco; Leônidas Lopes Braga Júnior; Janílson Moucherek Soares Nascimento; Gilnara Fontinelle Silva; Kemuel Pinto Bandeira

Dengue virus infection is endemic in tropical and subtropical areas. Symptomatic dengue infection is classified into dengue fever or dengue hemorrhagic fever with a tendency to develop shock syndrome. Dengue hemorrhagic fever is characterized by hemorrhagic manifestations, thrombocytopenia and increased capillary permeability. Dengue shock syndrome presents findings of dengue hemorrhagic fever with hypotension. Many sonographic findings have been described, including pleural effusion, ascites, gallbladder wall thickening and pericardial effusion. The aim of the present review is to describe sonographic findings and to demonstrate the role of ultrasonography in the assessment of children with suspected dengue hemorrhagic fever


Radiologia Brasileira | 2011

Lipoma espinhal associado a seio dérmico congênito: relato de caso

Lívia Teresa Moreira Rios; Ricardo Villar Barbosa de Oliveira; Marília da Glória Martins; Olga Maria Ribeiro Leitão; Vanda Maria Ferreira Simões; Janílson Moucherek Soares Nascimento

Spinal lipomas are rare, accounting for 1% of all spinal tumors and being associated with occult spinal dysraphism in more than 99% of cases. Such lesions are divided into three main types, namely, lipomyelomeningoceles, intradural lipomas, and filum terminale fibrolipomas. The present report describes a case of congenital lumbosacral lipoma associated with cutaneous stigmata of the lumbar dermal sinus type.


Archives of Gynecology and Obstetrics | 2012

Predictive model for spontaneous preterm labor among pregnant women with contractions and intact amniotic membranes

Ricardo Villar Barbosa de Oliveira; Marília da Glória Martins; Lívia Teresa Moreira Rios; Edward Araujo Júnior; Vanda Maria Ferreira Simões; Luciano Marcondes Machado Nardozza; Antonio Fernandes Moron


Urology Journal | 2014

Antenatal diagnosis of renal duplication by ultrasonography: report on four cases at a referral center.

Edward Enéas Dantas Queiroga Júnior; Marília da Glória Martins; Lívia Teresa Moreira Rios; Edward Araujo Júnior; Ricardo Villar Barbosa de Oliveira; Luciano Marcondes Machado Nardozza; Antonio Fernandes Moron


Ultrasound in Medicine and Biology | 2013

Antenatal Sonographic Diagnosis of Intraventricular Hemorrhage

Lívia Teresa Moreira Rios; V.S. Carvalho; Marília da Glória Martins; Ricardo Villar Barbosa de Oliveira; E. Araujo; Luciano Marcondes Machado Nardozza; A. F. Moron


Ultrasound in Medicine and Biology | 2013

Obstetric Ultrasound: Errors and Pitfalls in Fetal Growth Restriction

A.R. Pastore; Lívia Teresa Moreira Rios; Ricardo Villar Barbosa de Oliveira; L.C.L. Rios; E. Araujo; W.J. Hisaba; Luciano Marcondes Machado Nardozza; A. F. Moron


Ultrasound in Medicine and Biology | 2013

Sonographic Markers of Pelvic Inflammatory Disease

A.R. Pastore; Lívia Teresa Moreira Rios; Ricardo Villar Barbosa de Oliveira; Marília da Glória Martins; L.C.L. Rios; J.M.S. Nascimento; O.M.R. Leitão

Collaboration


Dive into the Ricardo Villar Barbosa de Oliveira's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

A. F. Moron

Federal University of São Paulo

View shared research outputs
Top Co-Authors

Avatar

Antonio Fernandes Moron

Federal University of São Paulo

View shared research outputs
Top Co-Authors

Avatar

Edward Araujo Júnior

Federal University of São Paulo

View shared research outputs
Top Co-Authors

Avatar

Gilnara Fontinelle Silva

Federal University of Maranhão

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Kemuel Pinto Bandeira

Federal University of Maranhão

View shared research outputs
Researchain Logo
Decentralizing Knowledge