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Pesquisa : D09.698.718 [Categoria DeCS]
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Id: biblio-886795
Autor: XU, CHUNPING; YU, JINWEI; ZHAO, SHANSHAN; WU, SHUNGSHUNG; HE, PEIXIN; JIA, XUEWEI; LIU, YANQI; MAO, DUOBIN.
Título: Effect of carbon source on production, characterization and bioactivity of exopolysaccharide produced by Phellinus vaninii Ljup
Fonte: An. acad. bras. ciênc;89(3,supl):2033-2041, 2017. tab, graf.
Idioma: en.
Projeto: National Science Foundation of China.
Resumo: ABSTRACT The effect on different three carbon source (i.e. glucose, fructose and sucrose) on production, chemical characterization and antioxidant activity of exopolysaccharide (EPS) produced by Phellinus vaninii Ljup was investigated in this study. Amongst carbon sources examined, glucose and sucrose were favorable for the mycelia growth, while the maximum EPS yield was achieved when sucrose was employed. The predominant carbohydrate compositions in EPSs identified were gluconic acid, glucose, mannose and galactose acid. Then, FT-IR spectral analysis revealed prominent characteristic groups in EPSs. EPSs molecule exist as nearly globular shape form in aqueous solution. The variation also affects antioxidant activities by investigated by using hydroxyl and DPPH radical scavenging assay. Sucrose was best carbon source from the viewpoint of antioxidant activity due to the relatively high contents of galactose in the EPS with moderate molecular weight and polydispersity.
Descritores: Polissacarídeos Bacterianos/metabolismo
Carbono/metabolismo
Polissacarídeos Fúngicos
-Sacarose/metabolismo
Espectroscopia de Infravermelho com Transformada de Fourier
Frutose/metabolismo
Glucose/metabolismo
Responsável: BR1.1 - BIREME


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Id: biblio-1116432
Autor: Demirhan, Tanju; Celik, Gokcen Yuvali; Katircioglu, Hikmet; Onbasli, Dilsad.
Título: Evaluation of anti-biofouling potential of Viburnum opulus extracts / Evaluación del potencial anti bioincrustante de extractos de Viburnum opulus
Fonte: Bol. latinoam. Caribe plantas med. aromát;19(3):321-333, mayo 2020. ilus, tab.
Idioma: en.
Projeto: Erciyes University Scientific Research Projects Unit.
Resumo: In this study the in vitro investigation of the inhibitory effect of ethanol extract of Viburnum opulus L. bark sample on Streptococcus mutans planctonic cells and biofilm has been intended. A Scanning electron microscopy analysis has been performed in order to investigate the inhibitory effect of the extract on Streptococcus mutans biofilms. Furthermore, the Exopolysaccharide and dextran production of this bacteria have been identified in the presence of the extract. It has been found out that the bark extract with the concentration of 2,5 mg/mL is able to inhibit more than 50% of the cells in the different times development phases. According to this, the exopolymeric matrix on the biofilm surface disperses and the Exopolysaccharide and dextran production get lowered in the presence of bark extract compared to the control group. It is considered that this extract can be used as an alternative approach for the new chemotherapeutic strategies against tooth decay.

En este estudio se investigó el efecto inhibitorio in vitro del extracto de etanólico de una muestra de corteza de Viburnum opulus L. en biopelículas de células planctónicas de Streptococcus mutans. Se realizó un análisis de microscopía electrónica de barrido para investigar el efecto inhibitorio del extracto sobre las biopelículas de Streptococcus mutans. Además, se identificó la producción de exopolisacárido y dextrano de esta bacteria en presencia del extracto. Se descubrió que el extracto de corteza con una concentración de 2,5 mg/ml inhibió más del 50% de las células en las diferentes fases de desarrollo. Consecuentemente, la matriz exopolimérica en la superficie de la biopelícula se dispersa y la producción de exopolisacárido y dextrano se reduce en presencia de extracto de corteza en comparación con el grupo de control. Se sugiere que este extracto puede ser usado como un enfoque alternativo para las nuevas estrategias quimioterapéuticas contra la carie dental.
Descritores: Streptococcus mutans/efeitos dos fármacos
Extratos Vegetais/farmacologia
Viburnum opulus/farmacologia
Viburnum/química
-Polissacarídeos Bacterianos/análise
Streptococcus mutans/metabolismo
Técnicas In Vitro
Microscopia Eletrônica de Varredura
Dextranos/análise
Biofilmes/efeitos dos fármacos
Etanol
Incrustação Biológica
Responsável: CL1.1 - Biblioteca Central


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Id: lil-107772
Autor: Calvo, B; Fischman, O; Castelo Filho, A; Reis Filho, J; Del Bianco, R; Barbosa, R.M; Zaror, L.
Título: Deteccion de antigeno del polisacarido capsular de Cryptococcus neoformans en pacientes con SIDA y neurocriptococosis en Sao Paulo, Brasil / Detection of capsular polysaccharide antigen of Cryptococcus neoformans in patients with AIDS and neurocryptococcosis in Sao Paulo, Brazil
Fonte: Rev. Inst. Med. Trop. Säo Paulo;33(6):485-90, nov.-dez. 1991. tab.
Idioma: es.
Resumo: Antigeno del polisacarido capsular (AgPC) de Cryptococcus neoformans fue detectado por la tecnica de aglutinacion de latex (AL) en LCR y suero de pacientes con Sindrome de Inmunodeficiencia Adquirida (SIDA) y primer episodio de neurocriptococosis, usando como patron el examen micologico (examen directo y cultivo) de LCR. Se obtuvo una sensibilidad de 100 por ciento de AL para detectar AgPC de C. neoformans, el cual por su rapidez permite tratamiento especifico precoz. Titulos iniciales de AgPC de la levadura en esos pacientes pueden ser>1.000.000, pareciendo que cuando esos titulos estan presentes en suero, se relacionan con mortalidad durante el tratamiento. En los pacientes que sobrevivieron se observo que el examen micologico directo y AgPC de C. neoformans, en LCR y suero, permanecen positivos aun despues de tratamiento y mejoria clinica del paciente.
Descritores: Polissacarídeos Bacterianos/imunologia
Encefalopatias/imunologia
Criptococose/imunologia
Cryptococcus neoformans/imunologia
Antígenos de Bactérias/isolamento & purificação
Síndrome de Imunodeficiência Adquirida/imunologia
-Encefalopatias/líquido cefalorraquidiano
Encefalopatias/mortalidade
Encefalopatias/sangue
Criptococose/líquido cefalorraquidiano
Criptococose/mortalidade
Criptococose/sangue
Antígenos de Bactérias/líquido cefalorraquidiano
Antígenos de Bactérias/sangue
Síndrome de Imunodeficiência Adquirida/sangue
Síndrome de Imunodeficiência Adquirida/líquido cefalorraquidiano
Síndrome de Imunodeficiência Adquirida/mortalidade
Limites: Adulto
Masculino
Feminino
Adolescente
Pessoa de Meia-Idade
Humanos
Responsável: BR66.1 - Divisão de Biblioteca e Documentação


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Ramos, Júlia Baruque
Raw, Isaias
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Id: lil-344561
Autor: Paz, Marcelo Fossa da; Ramos, Júlia Baruque; Hiss, Haroldo; Vicentin, Márcio Alberto; Leal, Maria Betania Batista; Raw, Isaías.
Título: Polysaccharide production in batch process of Neisseria meningitidis serogroup C comparing Frantz, modified Frantz and Cartlin 6 cultivation media
Fonte: Braz. j. microbiol;34(1):27-32, Jan.-Apr. 2003. tab, graf.
Idioma: en.
Resumo: Polysaccharide of N. meningitidis serogroup C constitutes the antigen for the vaccine against meningitis. The goal of this work was to compare three cultivation media for production of this polysaccharide: Frantz, modified Frantz medium (with replacement of glucose by glycerol), and Catlin 6 (a synthetic medium with glucose). The comparative criteria were based on the final polysaccharide concentrations and the yield coefficient cell/polysaccharide (Y P/X). The kinetic parameters: pH, substrate consumption and cell growth were also determined. For this purpose, 9 cultivation runs were carried out in a 80 L New Brunswick bioreactor, under the following conditions: 42 L of culture medium, temperature 35°C, air flow 5 L/min, agitation frequency 120 rpm and vessel pressure 6 psi, without dissolved oxygen or pH controls. The cultivation runs were divided in three groups, with 3 repetitions each. The cultivation using the Frantz medium presented the best results: average of final polysaccharide concentration = 0.134 g/L and Y P/X=0.121, followed by Catlin 6 medium, with results of 0.095 g/L and 0.067 respectively. Considering the principal advantages in the use of the synthetic medium, i.e. facilitation of a cultivation and purification steps of the polysaccharide production process, there is a possibility that in the near future, Catlin 6 will replace the traditional Frantz medium.
Descritores: Técnicas In Vitro
Neisseria meningitidis Sorogrupo C/genética
Neisseria meningitidis Sorogrupo C/isolamento & purificação
Neisseria meningitidis Sorogrupo C/patogenicidade
Polissacarídeos Bacterianos/análise
Polissacarídeos Bacterianos/isolamento & purificação
Vacinas Meningocócicas/isolamento & purificação
-Meios de Cultura
Tipo de Publ: Revisão de Integridade Científica
Estudo Comparativo
Responsável: BR32.1 - Serviço de Biblioteca e Informação Biomédica


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Raw, Isaias
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Id: lil-314803
Autor: Ramos-Buraque, Júlia; Hiss, Haroldo; Vicentim, Márcio Alberto; Paz, Marcelo Fossa da; Peixoto, Argélia; Leal, Maria Betania Batista; Sato, Rony Akio; Vassoler, Umbelina Macedo; Raw, Isaías.
Título: Nitrogen consumption during batch cultivation of Neisseria meningitidis (serogroup c) in Frantz medium
Fonte: Braz. j. microbiol;32(4):305-310, Oct.-Dec. 2001. tab, graf.
Idioma: en.
Resumo: Capsular polysaccharide, extracted from microorganism cultivations, is the principal antigen for elaboration of vaccine against the disease caused by Neisseria meningitidis serogroup C. The final protein content allowed in this vaccine is 1 (per cent). In order to find a relationship between nitrogen consumption and cell growth, including polysaccharide production, and cell nitrogen content, cultivations were carried out in an 80 liters bioreactor (total capacity), under the following conditions: Frantz medium; temperature of 35ºC; air flow of 5L/min (0.125vvm); agitation frequency of 120 rpm and vessel pressure of 6 psi (k(L)a=0.07min(-1).Concentrations of biomass, total polysaccharide, cellular nitrogen, residual organic and inorganic nitrogen in the medium were measured during cultivation. From five cultivations carried out under the same conditions, a mean cell nitrogen percentage of 12.6(per cent)(w/w) in respect to the dry biomass was found. The inorganic nitrogen in the medium did not change significantly along the cultivation time, whereas the organic nitrogen consuption was linearly related to cell growth, with constant yeield factors (average of 8.44). Polysaccharide production kinetics followed the cell growth kinetics until the beginning of the stationary growth phase. A supplemental polysaccharide production was observed until the end of cultivation, but without cell nitrogen absorption. Thus, the results indicate that polysaccharide is produced in two phases, being the first one biomass formation followed by non-associated to growth. /
Descritores: Polissacarídeos
Polissacarídeos Bacterianos
Vacinas Bacterianas
Neisseria meningitidis
Técnicas In Vitro
Proteínas de Bactérias/análise
Proteínas de Bactérias/isolamento & purificação
-Meios de Cultura
Testes Sorológicos/métodos
Tipo de Publ: Revisão de Integridade Científica
Responsável: BR32.1 - Serviço de Biblioteca e Informação Biomédica


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Id: biblio-949378
Autor: Maia, Guilherme Tavares da Silva; Albuquerque, Amanda Vasconcelos de; Martins Filho, Euclides Dias; Lira Neto, Filipe Tenório de; Souza, Veridiana Sales Barbosa de; Silva, Anderson Arnaldo da; Lira, Mariana Montenegro de Melo; Lima, Salvador Vilar Correia.
Título: Bacterial cellulose to reinforce urethrovesical anastomosis. A translational study
Fonte: Acta cir. bras;33(8):673-683, Aug. 2018. tab, graf.
Idioma: en.
Resumo: Abstract Purpose: To evaluate the efficacy of the cellulosic exopolysaccharide membrane (CEM) as a urethral reinforcement for urethrovesical anastomosis. Methods: Twenty eight rabbits were submitted to urethrovesical anastomosis with or without CEM reinforcement. The animals were divided into 4 groups: C7, CEM7, C14 and CEM14: (C= only anastomosis or CEM = anastomosis + CEM), evaluated after 7 weeks, and 14 weeks. The biointegration and biocompatibility of CEM were evaluated according to stenosis, fistula, urethral wall thickness, urethral epithelium, rate of inflammation and vascularization. Results: Between the two experimental groups, the difference in the number of stenosis or urinary fistula was not statistically significant. The morphometric analysis revealed preservation of urethral lumen, well adhered CEM without extrusion, a controlled inflammatory process and implant vascularization. The urothelium height remained constant over time after CEM reinforcement and the membrane wall was thicker, statistically, after 14 weeks. Conclusion: The absence of extrusion, stenosis or urinary fistula after 14 weeks of urethrovesical anastomosis demonstrates cellulosic exopolysaccharide membrane biocompatibility and biointegration with tendency to a thicker wall.
Descritores: Uretra/cirurgia
Materiais Biocompatíveis/uso terapêutico
Bexiga Urinária/cirurgia
Celulose/uso terapêutico
-Polissacarídeos Bacterianos/uso terapêutico
Fatores de Tempo
Uretra/patologia
Bexiga Urinária/patologia
Microbiologia Industrial/métodos
Teste de Materiais
Anastomose Cirúrgica
Celulose/biossíntese
Reprodutibilidade dos Testes
Resultado do Tratamento
Pesquisa Médica Translacional
Neovascularização Patológica
Limites: Animais
Masculino
Coelhos
Tipo de Publ: Estudo de Avaliação
Responsável: BR1.1 - BIREME


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Id: biblio-951792
Autor: Moghannem, Saad A. M; Farag, Mohamed M. S; Shehab, Amr M; Azab, Mohamed S.
Título: Exopolysaccharide production from Bacillus velezensis KY471306 using statistical experimental design
Fonte: Braz. j. microbiol;49(3):452-462, July-Sept. 2018. tab, graf.
Idioma: en.
Resumo: Abstract Exopolysaccharide (EPS) biopolymers produced by microorganisms play a crucial role in the environment such as health and bio-nanotechnology sectors, gelling agents in food and cosmetic industries in addition to bio-flocculants in the environmental sector as they are degradable, nontoxic. This study focuses on the improvement of EPS production through manipulation of different culture and environmental conditions using response surface methodology (RSM). Plackett-Burman design indicated that; molasses, yeast extract and incubation temperature are the most effective parameters. Box-Behnken RSM indicated that; the optimum concentration for each parameter was 12% (w/v) for molasses, 6 g/L yeast extract and 30 °C for incubation temperature. The most potent bacterial isolate was identified as Bacillus velezensis KY498625. After production, EPS was extracted, purified using DEAE-cellulose, identified using Fourier transform infrared (FTIR), gel permeation chromatography (GPC) and gas chromatography-mass spectroscopy (GC-MS). The result indicated that; it has molecular weight 1.14 × 105 D consisting of glucose, mannose and galactose.
Descritores: Polissacarídeos Bacterianos/metabolismo
Bacillus/metabolismo
-Polissacarídeos Bacterianos/isolamento & purificação
Polissacarídeos Bacterianos/química
Bacillus/química
Microbiologia Industrial
Espectroscopia de Infravermelho com Transformada de Fourier
Meios de Cultura/metabolismo
Meios de Cultura/química
Peso Molecular
Responsável: BR1.1 - BIREME


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Id: lil-797977
Autor: Lei, Lei; Shao, Meiying; Yang, Yan; Mao, Mengying; Yang, Yingming; Hu, Tao.
Título: Exopolysaccharide dispelled by calcium hydroxide with volatile vehicles related to bactericidal effect for root canal medication
Fonte: J. appl. oral sci;24(5):487-495, Sept.-Oct. 2016. graf.
Idioma: en.
Projeto: National Natural Science Foundation of China.
Resumo: ABSTRACT Objective: Enterococcus faecalis is the dominant microbial species responsible for persistent apical periodontitis with ability to deeply penetrate into the dentin. Exopolysaccharides (EPS) contribute to the pathogenicity and antibiotic resistance of E. faecalis. Our aim was to investigate the antimicrobial activity of calcium hydroxide (CH), camphorated parachlorophenol (CMCP), and chlorhexidine (CHX) against E. faecalis in dentinal tubules. Material and Methods: Decoronated single-canal human teeth and semicylindrical dentin blocks were incubated with E. faecalis for 3 weeks. Samples were randomly assigned to six medication groups for 1 week (n=10 per group): CH + 40% glycerin-water solution (1:1, wt/vol); CMCP; 2% CHX; CH + CMCP (1:1, wt/vol); CH + CMCP (2:3, wt/vol); and saline. Bacterial samples were collected and assayed for colony-forming units. After dentin blocks were split longitudinally, confocal laser scanning microscopy was used to assess the proportion of viable bacteria and EPS production in dentin. Results: CMCP exhibited the best antimicrobial activity, while CH was the least sensitive against E. faecalis (p<0.05). CHX showed similar antimicrobial properties to CH + CMCP (1:1, wt/vol) (p>0.05). CH combined with CMCP inhibited EPS synthesis by E. faecalis, which sensitized biofilms to antibacterial substances. Moreover, increasing concentrations of CMCP decreased EPS matrix formation, which effectively sensitized biofilms to disinfection agents. Conclusion: The EPS matrix dispelled by CH paste with CMCP may be related to its bactericidal effect; the visualization and analysis of EPS formation and microbial colonization in dentin may be a useful approach to verify medicaments for antimicrobial therapy.
Descritores: Polissacarídeos Bacterianos/química
Irrigantes do Canal Radicular/farmacologia
Veículos Farmacêuticos/farmacologia
Hidróxido de Cálcio/farmacologia
Enterococcus faecalis/efeitos dos fármacos
Dentina/efeitos dos fármacos
Antibacterianos/farmacologia
-Fatores de Tempo
Cânfora/farmacologia
Contagem de Colônia Microbiana
Clorofenóis/farmacologia
Reprodutibilidade dos Testes
Estatísticas não Paramétricas
Microscopia Confocal
Biofilmes/efeitos dos fármacos
Cavidade Pulpar/efeitos dos fármacos
Cavidade Pulpar/microbiologia
Dentina/microbiologia
Combinação de Medicamentos
Viabilidade Microbiana/efeitos dos fármacos
Limites: Humanos
Adolescente
Adulto
Adulto Jovem
Responsável: BR1.1 - BIREME


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Id: biblio-1021065
Autor: Demirci, Ahmet Sukru; Palabiyik, Ibrahim; Altan, Deniz Damla; Apaydin, Demet; Gumus, Tuncay.
Título: Yield and rheological properties of exopolysaccharide from a local isolate: Xanthomonas axonopodis pv. vesicatoria
Fonte: Electron. j. biotechnol;30:18-23, nov. 2017. ilus, tab, graf.
Idioma: en.
Projeto: The Scientific and Technological Research Council of Turkey (TUBITAK).
Resumo: Background: The aim of the present study was to evaluate gum productivity of a local strain, Xanthomonas axonopodis pv. vesicatoria, isolated from pepper plant, and its rheological behavior for the first time compared to the standard strain, Xanthomonas campestris DSM 19000 (NRRL B-1459). The influence of operational conditions (agitation rate and inoculum volume) on gum production and rheological properties of gums from the Xanthomonas strains were investigated. Results: The isolated strain of Xanthomonas showed similar xanthan yield compared to the standard strain. Furthermore, this study clearly confirmed that gum yield depended on bacterial strain, agitation rate, and inoculum size. The most suitable conditions for the gum production in an orbital shaker in terms of agitation rate and inoculum size were 180 rpm and 5%, respectively, resulting in an average production of 10.96 and 11.19 g/L for X. axonopodis pv.vesicatoria and X. campestris DSM 19000, respectively. Regarding the rheological properties, Ostwald-de-Waele and power law models were used to describe flow and oscillatory behavior of the gum solutions, respectively. Consistency of the novel gum solution remarkably was much higher than the commercial xanthan gum solution. Flow and oscillatory behavior and their temperature ramps showed that weak gel-like structure could be obtained with less gum concentrations when the novel gum was used. Conclusion: Therefore, yield and technological properties of the aqueous solutions of the exopolysaccharide synthesized by X. axonopodis pv. vesicatoria were observed to be more suitable for industrial production.
Descritores: Polissacarídeos Bacterianos/biossíntese
Xanthomonas vesicatoria/metabolismo
Xanthomonas axonopodis/metabolismo
-Reologia
Temperatura
Viscosidade
Biodegradação Ambiental
Capsicum
Xanthomonas campestris/metabolismo
Responsável: CL1.1 - Biblioteca Central


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Id: biblio-1015826
Autor: Vásquez-Ponce, Felipe; Higuera-Llantén, Sebastián; Pavlov, María Soledad; Ramírez-Orellana, Ramón; Marshall, Sergio H; Olivares-Pacheco, Jorge.
Título: Alginate overproduction and biofilm formation by psychrotolerant Pseudomonas mandelii depend on temperature in Antarctic marine sediments
Fonte: Electron. j. biotechnol;28:27-34, July. 2017. tab, ilus, graf.
Idioma: en.
Projeto: Dirección de Investigación, Pontificia Universidad Católica de Valparaíso.
Resumo: Background: In recent years, Antarctica has become a key source of biotechnological resources. Native microorganisms have developed a wide range of survival strategies to adapt to the harsh Antarctic environment, including the formation of biofilms. Alginate is the principal component of the exopolysaccharide matrix in biofilms produced by Pseudomonas, and this component is highly demanded for the production of a wide variety of commercial products. There is a constant search for efficient alginate-producing organisms. Results: In this study, a novel strain of Pseudomonas mandelii isolated from Antarctica was characterized and found to overproduce alginate compared with other good alginate producers such as Pseudomonas aeruginosa and Pseudomonas fluorescens. Alginate production and expression levels of the alginate operon were highest at 4°C. It is probable that this alginate-overproducing phenotype was the result of downregulated MucA, an anti-sigma factor of AlgU. Conclusion: Because biofilm formation is an efficient bacterial strategy to overcome stressful conditions, alginate overproduction might represent the best solution for the successful adaptation of P. mandelii to the extreme temperatures of the Antarctic. Through additional research, it is possible that this novel P. mandelii strain could become an additional source for biotechnological alginate production.
Descritores: Pseudomonas/metabolismo
Alginatos/metabolismo
-Polissacarídeos Bacterianos/metabolismo
Pseudomonas/crescimento & desenvolvimento
Pseudomonas/genética
Adaptação Biológica
Temperatura Baixa
Microscopia Confocal
Biofilmes
Feófitas
Tipagem de Sequências Multilocus
Reação em Cadeia da Polimerase em Tempo Real
Regiões Antárticas
Responsável: CL1.1 - Biblioteca Central



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