Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
Más filtros

País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
An Acad Bras Cienc ; 92(1): e20190336, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32321026

RESUMEN

Uncaria tomentosa (UT) extracts have been shown to have promising anti-tumor activity. We hypothesized that its incorporation into nanostructured systems could improve the anticancer properties. Here, poly-e-caprolactone (PCL) and poly-d,l-lactide-co-glycolide (PLGA) were employed to generate nanoparticles loaded with UT extract in a single emulsion solvent evaporation method. The nanoparticles were characterized by particle size, zeta potential, morphology and entrapment efficiency along with stability and release profiles. The nanoparticles presented entrapment efficiencies above 60% and a mean diameter below 300nm. UT-PCL nanoparticles presented higher entrapment efficiency and mean particle size as well as a slow release rate. The UT-PLGA nanoparticles showed higher drug loading. Two prostate cancer cell-lines, LNCaP and DU145 that were derived from metastatic sites, served as model systems to assess cytotoxicity and anti-cancer activity. In vitro, both formulations reduced the viability of DU145 and LNCaP cells. Yet, the UT-PLGA nanoparticles showed higher cytotoxicity towards DU145 cells while the UTPCL against LNCaP cells. The results confirm that the incorporation of UT into nanoparticles could enhance its anti-cancer activities that can offer a viable alternative for the treatment of prostrate canner and highlights the potential of nanostructured systems to provide a promising methodology to enhance the activity of natural extracts.


Asunto(s)
Antineoplásicos/farmacología , Uña de Gato/química , Extractos Vegetales/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos , Humanos , Nanopartículas
2.
Biotechnol Bioeng ; 111(10): 2009-18, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24729067

RESUMEN

Granular activated carbon (GAC) is used in water treatment systems, typically to remove pollutants such as natural organic matter, volatile organic compounds, chlorine, taste, and odor. GAC is also used as a key component of a new technology that combines a fluidized bed reactor with radio frequency electric fields for disinfection. So far, the effects of GAC on bacteria in these fluidized bed reactors are unclear. This paper describes a systematic study of the physico-chemical changes in five microbial media compositions caused by different concentrations (23-350 g/L) of GAC, and the effects of these physico-chemical changes on the metabolic activity and survival of a model microorganism (Escherichia coli YMc10) in a fluidized bed reactor. The chemical adsorption taking place in suspensions with specific GAC changed nutritional, osmotic, and pH conditions in the investigated microbial media (LB, diluted LB, PBS, diluted PBS, and tap water), leading to a decay of the metabolic activity and survival of E. coli. Especially media that are poor in organic and mineral compounds (e.g., PBS) with suspended GAC showed a concentration decay of 3.5 Log CFU/mL E. coli after 6 h. Organic compounds depletion and severe pH variation were enhanced in the presence of higher GAC concentrations.


Asunto(s)
Carbón Orgánico/metabolismo , Desinfección/métodos , Escherichia coli/citología , Adsorción , Medios de Cultivo/metabolismo , Escherichia coli/metabolismo , Concentración de Iones de Hidrógeno , Viabilidad Microbiana , Concentración Osmolar , Sales (Química)/metabolismo
3.
Am J Trop Med Hyg ; 103(1): 38-40, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32228776

RESUMEN

In the most recent Brazilian yellow fever (YF) outbreak, a group of clinicians and researchers initiated in mid-January 2018 a considerable effort to develop a multicenter randomized controlled clinical trial to evaluate the effect of sofosbuvir on YF viremia and clinical outcomes (Brazilian Clinical Trials Registry: RBR-93dp9n). The approval of this protocol had urgency given the seasonal/short-lived pattern of YF transmission, large number of human cases, and epidemic transmission at the outskirts of a large urban center. However, many intricacies in the research regulatory and ethical submission systems in Brazil were indomitable even under such pressing conditions. By April 2018, we had enrolled 29 patients for a target sample size of 90 participants. Had enrollment been initiated 3 weeks earlier, an additional 31 patients could have been enrolled, reaching the prespecified sample size for the interim analysis. This recent experience highlights the urgent need to improve local preparedness for research in the setting of explosive outbreaks, as has been seen in the last few years in different countries.


Asunto(s)
Investigación Biomédica/legislación & jurisprudencia , Enfermedades Transmisibles Emergentes/epidemiología , Brotes de Enfermedades , Ensayos Clínicos Controlados Aleatorios como Asunto/legislación & jurisprudencia , Viremia/epidemiología , Fiebre Amarilla/epidemiología , Virus de la Fiebre Amarilla/patogenicidad , Aedes/virología , Animales , Antivirales/uso terapéutico , Investigación Biomédica/ética , Brasil/epidemiología , Enfermedades Transmisibles Emergentes/tratamiento farmacológico , Enfermedades Transmisibles Emergentes/virología , Regulación Gubernamental , Hospitalización/estadística & datos numéricos , Humanos , Mosquitos Vectores/virología , Selección de Paciente/ética , Ensayos Clínicos Controlados Aleatorios como Asunto/ética , Sofosbuvir/uso terapéutico , Viremia/tratamiento farmacológico , Fiebre Amarilla/tratamiento farmacológico , Fiebre Amarilla/virología , Virus de la Fiebre Amarilla/efectos de los fármacos , Virus de la Fiebre Amarilla/fisiología
4.
Vaccine ; 34(46): 5604-5611, 2016 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-27692770

RESUMEN

In March 2010, Brazil introduced the 10-valent pneumococcal conjugate vaccine (PCV10) in the routine infant immunization program using a 4-dose schedule and catch-up for children <23months. We investigated PCV10 effect on nasopharyngeal carriage with vaccine-type Streptococcus pneumoniae (Spn) and non-typeable Haemophilus influenzae (NTHi) among children in São Paulo city. Cross-sectional surveys were conducted in 2010 (baseline) and 2013 (post-PCV10). Healthy PCV-naïve children aged 12-23months were recruited from primary health centers during immunization campaigns. Nasopharyngeal swabs were collected and tested for Hi; for Spn, all baseline and a stratified random sample of 400 post-PCV10 swabs were tested. We compared vaccine-type Spn and NTHi carriage prevalence pre-/post-PCV10, and used logistic regression to estimate PCV10 effectiveness (1-adjusted odds ratio×100%). Overall 501 children were included in the baseline and 1167 in the post-PCV10 survey (including 400 tested for Spn). Spn was detected in 40.3% of children at baseline and 48.8% post-PCV10; PCV10 serotypes were found in 19.8% and 1.8% respectively, representing a decline of 90.9% (p<0.0001). Carriage of vaccine-related serotypes increased (10.8-21.0%, p<0.0001), driven primarily by a rise in serotype 6C (1.8-11.2%, p<0.0001); carriage of serotypes 6A and 19A did not significantly change. PCV10 effectiveness (4 doses) against vaccine-type carriage was 97.3% (95% confidence interval 88.7-99.3). NTHi prevalence increased from 26.0% (130/501) to 43.6% (509/1167, p<0.0001); PCV10 vaccination seemed significantly associated with NTHi carriage, even after adjusting for other known risk factors. Carriage with PCV10 serotypes among toddlers declined dramatically following PCV10 introduction in São Paulo, Brazil. No protection of PCV10 against NTHi was observed. Our findings contribute to a growing body of evidence of PCV10 impact on vaccine-type carriage and highlight the importance of PCV10 as a tool to reduce the burden of pneumococcal disease in Brazil and globally.


Asunto(s)
Portador Sano/prevención & control , Infecciones por Haemophilus/prevención & control , Haemophilus influenzae/aislamiento & purificación , Nasofaringe/microbiología , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas/inmunología , Streptococcus pneumoniae/aislamiento & purificación , Brasil/epidemiología , Portador Sano/epidemiología , Portador Sano/microbiología , Estudios Transversales , Femenino , Infecciones por Haemophilus/epidemiología , Infecciones por Haemophilus/microbiología , Humanos , Programas de Inmunización , Lactante , Modelos Logísticos , Masculino , Infecciones Neumocócicas/epidemiología , Infecciones Neumocócicas/microbiología , Vacunas Neumococicas/administración & dosificación , Serogrupo
5.
J Travel Med ; 21(5): 298-303, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24889210

RESUMEN

BACKGROUND: In February 2012, crew and passengers of a cruise ship sailing off the coast of São Paulo, Brazil, were hospitalized for acute respiratory illness (ARI). A field investigation was performed to identify the disease involved and factors associated. METHODS: Information on passengers and crew with ARI was obtained from the medical records of hospitalized individuals. Active case finding was performed onboard the ship. ARI was defined as the presence of one nonspecific symptom (fever, chills, myalgia, arthralgia, headache, or malaise) and one respiratory symptom (cough, nasal congestion, sore throat, or dyspnea). A case-control study was conducted among the crew. The cases were crew members with symptoms of influenza-like illness (ILI) (fever and one of the following symptoms: cough, sore throat, and dyspnea) in February 2012. The controls were asymptomatic crew members. RESULTS: The study identified 104 ARI cases: 54 (51.9%) crew members and 50 (49.1%) passengers. Among 11 ARI hospitalized cases, 6 had influenza B virus isolated in nasopharyngeal swab. One mortality among these patients was caused by postinfluenza Staphylococcus aureus pneumonia. The crew members housed in the two lower decks and those belonging to the 18- to 32-year-old age group were more likely to develop ILI [odds ratio (OR) = 2.39, 95% confidence interval (CI) 1.09-5.25 and OR = 3.72, CI 1.25-11.16, respectively]. CONCLUSIONS: In February 2012, an influenza B outbreak occurred onboard a cruise ship. Among crew members, ILI was associated with lower cabin location and younger age group. This was the first influenza outbreak detected by Brazilian public health authorities in a vessel cruising in South American waters.


Asunto(s)
Brotes de Enfermedades , Virus de la Influenza B/aislamiento & purificación , Gripe Humana/epidemiología , Navíos , Viaje , Adolescente , Adulto , Factores de Edad , Brasil/epidemiología , Estudios de Casos y Controles , Femenino , Humanos , Control de Infecciones , Gripe Humana/prevención & control , Masculino , Persona de Mediana Edad
6.
Clin Vaccine Immunol ; 21(5): 636-40, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24599531

RESUMEN

Pertussis remains an important public health problem in many countries despite extensive immunization. Cultures and real-time PCR (RT-PCR) assays are the recommended pertussis diagnostic tests, but they lack sensitivity at the later stage of the disease. This study introduces the IgG anti-pertussis toxin enzyme-linked immunosorbent assay (PT ELISA) in our routine diagnosis to improve disease burden estimation. Serum samples and nasopharyngeal swabs (n = 503) were collected at the same time from patients presenting with cough illness suspected of being pertussis and tested by the PT ELISA and culture and/or RT-PCR, respectively. Patients were separated into three age groups: group 1, <1 year (n = 260; mean age, 3 months), group 2, 1 to 6 years (n = 81; mean age, 3 years), and group 3, ≥7 years (n = 162; mean age, 26 years). The times (means) from cough onset to specimen collection were 16, 24, and 26 days, respectively. In group 1, 83 (82.2%) of 101 positive cases were positive for pertussis by culture/RT-PCR, while 40 (39.6%) tested positive by PT ELISA. In group 2, 6 (19.4%) of 31 positive cases were culture/RT-PCR positive, and 29 (93.6%) were seropositive. In group 3, 13 (13.8%) of 94 positive cases were positive by culture/RT-PCR and 91 (96.8%) were positive by serology. Culture/RT-PCR detected more cases of pertussis in infants (P < 0.0001), whereas the PT ELISA detected more cases in adolescents and adults (P < 0.0001). The timing between cough onset and specimen collection or recent vaccination may have partially affected our results. Serology is a suitable, cost-effective, and complementary pertussis diagnostic tool, especially among older children, adolescents, and adults during the later disease phase.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Pruebas Diagnósticas de Rutina/métodos , Tos Ferina/diagnóstico , Adolescente , Adulto , Anciano , Técnicas Bacteriológicas/métodos , Bordetella pertussis/genética , Bordetella pertussis/crecimiento & desarrollo , Bordetella pertussis/inmunología , Bordetella pertussis/aislamiento & purificación , Brasil , Niño , Preescolar , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Humanos , Inmunoglobulina G/sangre , Lactante , Masculino , Persona de Mediana Edad , Técnicas de Diagnóstico Molecular/métodos , Nasofaringe/microbiología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Sensibilidad y Especificidad , Pruebas Serológicas/métodos , Adulto Joven
7.
PLoS One ; 6(6): e20675, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21731621

RESUMEN

Real-time (RT)-PCR increases diagnostic yield for bacterial meningitis and is ideal for incorporation into routine surveillance in a developing country. We validated a multiplex RT-PCR assay for Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae in Brazil. Risk factors for being culture-negative, RT-PCR positive were determined. The sensitivity of RT-PCR in cerebrospinal fluid (CSF) was 100% (95% confidence limits, 96.0%-100%) for N. meningitidis, 97.8% (85.5%-99.9%) for S. pneumoniae, and 66.7% (9.4%-99.2%) for H. influenzae. Specificity ranged from 98.9% to 100%. Addition of RT-PCR to routine microbiologic methods increased the yield for detection of S. pneumoniae, N. meningitidis, and H. influenzae cases by 52%, 85%, and 20%, respectively. The main risk factor for being culture negative and RT-PCR positive was presence of antibiotic in CSF (odds ratio 12.2, 95% CI 5.9-25.0). RT-PCR using CSF was highly sensitive and specific and substantially added to measures of meningitis disease burden when incorporated into routine public health surveillance in Brazil.


Asunto(s)
Meningitis Bacterianas/microbiología , Vigilancia de la Población/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Técnicas de Tipificación Bacteriana , Brasil , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Recuento de Leucocitos , Masculino , Meningitis Bacterianas/sangre , Meningitis Bacterianas/líquido cefalorraquídeo , Persona de Mediana Edad , Análisis Multivariante , Neisseria meningitidis/clasificación , Neisseria meningitidis/genética , Reproducibilidad de los Resultados , Factores de Riesgo , Sensibilidad y Especificidad , Adulto Joven
8.
Arq Bras Endocrinol Metabol ; 52(6): 1031-8, 2008 Aug.
Artículo en Portugués | MEDLINE | ID: mdl-18820815

RESUMEN

Apoptosis, proliferation and histomorphometry of spleen were investigated in ovariectomized and non-ovariectomized adult Wistar rats maintained in hypothyroidism induced by daily administration of propylthiouracil (PTU) during 120 days. Two groups ovariectomized euthyroid and non-ovariectomized euthyroid were used as controls. Plasma was collected for free T4 dosage and the spleen for histomorphometry analysis, apoptosis index and the immunohistochemistry expression of caspase 3 and CDC47. Values of free T4 were lower in rats treated with PTU (p<0.05). In the hypothyroid groups there was some decrease in the spleen weight as well as the number and size of lymphoid follicles and there was some increase in the apoptotic index and the caspase 3 expression (p<0.05). However, the increase in the apoptosis index and the expression of caspase 3 in ovariectomized hypothyroid rats spleen was less accentuated than non-ovariectomized hypothyroid ones (p<0.05). The ovariectomized euthyroid group presented white pulp hyperplasia in comparison to the non-ovariectomized euthyroid group. There was no difference in the CDC47 expression between groups. It was concluded that the thyroid and ovarian hypofunction have distinct effects on the spleen and that in the hypothyroidism-hypogonadism association, the increase in the apoptosis index and in the expression of splenic caspase 3 is not as much as in isolated hypothyroidism.


Asunto(s)
Apoptosis , Proliferación Celular , Hipotiroidismo/metabolismo , Ovariectomía , Bazo , Glándula Tiroides/metabolismo , Adenosina Trifosfatasas/análisis , Adenosina Trifosfatasas/metabolismo , Animales , Antitiroideos , Caspasa 3/análisis , Caspasa 3/metabolismo , Proteínas de Unión al ADN/análisis , Proteínas de Unión al ADN/metabolismo , Modelos Animales de Enfermedad , Femenino , Hipogonadismo/metabolismo , Hipotiroidismo/sangre , Hipotiroidismo/inducido químicamente , Tejido Linfoide/metabolismo , Tejido Linfoide/patología , Componente 7 del Complejo de Mantenimiento de Minicromosoma , Propiltiouracilo , Ratas , Ratas Wistar , Bazo/citología , Bazo/metabolismo , Bazo/patología , Glándula Tiroides/citología , Tiroxina/sangre
9.
Arq. bras. endocrinol. metab ; 52(6): 1031-1038, ago. 2008. ilus, graf
Artículo en Portugués | LILACS | ID: lil-492935

RESUMEN

Apoptose, proliferação e histomorfometria do baço foram investigados em ratas Wistar adultas ovariectomizadas e não-ovariectomizadas, mantidas em hipotireoidismo induzido pela administração diária de propiltiouracil (PTU) por 120 dias. Dois grupos eutireóideos ovariectomizados e não-ovariectomizados serviram como controle. Foi colhido o plasma para dosagem de T4 livre e o baço para análise da histomorfometria, do índice apoptótico e da expressão imunohistoquímica de caspase 3 e CDC47. Valores de T4 livre foram menores nas ratas tratadas com PTU (p < 0,05). Nos grupos hipotireóideos houve redução do peso do baço, do número e do tamanho dos folículos linfóides e aumento do índice apoptótico e da expressão de caspase 3 (p < 0,05). Porém, o baço de ratas hipotireóideas ovariectomizadas apresentou aumento menos acentuado do índice apoptótico e da expressão de caspase 3 do que o baço de ratas hipotireóideas não-ovariectomizadas (p < 0,05). O grupo eutireóideo ovariectomizado apresentou hiperplasia da polpa branca em relação ao grupo eutireóideo não-ovariectomizado. Não houve diferença na expressão de CDC47 entre os grupos. Conclui-se que a hipofunção tireoidiana e gonadal apresentam efeitos distintos no baço e que na associação hipotireoidismo-hipogonadismo há aumento menos acentuado do índice apoptótico e da expressão de caspase-3 esplênica do que no hipotireoidismo isolado.


Apoptosis, proliferation and histomorphometry of spleen were investigated in ovariectomized and non-ovariectomized adult Wistar rats maintained in hypothyroidism induced by daily administration of propylthiouracil (PTU) during 120 days. Two groups ovariectomized euthyroid and non-ovariectomized euthyroid were used as controls. Plasma was collected for free T4 dosage and the spleen for histomorphometry analysis, apoptosis index and the immunohistochemistry expression of caspase 3 and CDC47. Values of free T4 were lower in rats treated with PTU (p<0.05). In the hypothyroid groups there was some decrease in the spleen weight as well as the number and size of lymphoid follicles and there was some increase in the apoptotic index and the caspase 3 expression (p<0.05). However, the increase in the apoptosis index and the expression of caspase 3 in ovariectomized hypothyroid rats spleen was less accentuated than non-ovariectomized hypothyroid ones (p<0.05). The ovariectomized euthyroid group presented white pulp hyperplasia in comparison to the non-ovariectomized euthyroid group. There was no difference in the CDC47 expression between groups. It was concluded that the thyroid and ovarian hypofunction have distinct effects on the spleen and that in the hypothyroidism-hypogonadism association, the increase in the apoptosis index and in the expression of splenic caspase 3 is not as much as in isolated hypothyroidism.


Asunto(s)
Animales , Femenino , Ratas , Apoptosis , Proliferación Celular , Hipotiroidismo/metabolismo , Ovariectomía , Bazo , Glándula Tiroides/metabolismo , Antitiroideos , Adenosina Trifosfatasas/análisis , Adenosina Trifosfatasas/metabolismo , /análisis , /metabolismo , Modelos Animales de Enfermedad , Proteínas de Unión al ADN/análisis , Proteínas de Unión al ADN/metabolismo , Hipogonadismo/metabolismo , Hipotiroidismo/sangre , Hipotiroidismo/inducido químicamente , Tejido Linfoide/metabolismo , Tejido Linfoide/patología , Propiltiouracilo , Ratas Wistar , Bazo/citología , Bazo/metabolismo , Bazo/patología , Glándula Tiroides/citología , Tiroxina/sangre
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA