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1.
An Acad Bras Cienc ; 92(1): e20190336, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32321026

RESUMO

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.


Assuntos
Antineoplásicos/farmacologia , Unha-de-Gato/química , Extratos Vegetais/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos , Humanos , Nanopartículas
2.
Biotechnol Bioeng ; 111(10): 2009-18, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24729067

RESUMO

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.


Assuntos
Carvão Vegetal/metabolismo , Desinfecção/métodos , Escherichia coli/citologia , Adsorção , Meios de Cultura/metabolismo , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio , Viabilidade Microbiana , Concentração Osmolar , Sais/metabolismo
3.
Am J Trop Med Hyg ; 103(1): 38-40, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32228776

RESUMO

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.


Assuntos
Pesquisa Biomédica/legislação & jurisprudência , Doenças Transmissíveis Emergentes/epidemiologia , Surtos de Doenças , Ensaios Clínicos Controlados Aleatórios como Assunto/legislação & jurisprudência , Viremia/epidemiologia , Febre Amarela/epidemiologia , Vírus da Febre Amarela/patogenicidade , Aedes/virologia , Animais , Antivirais/uso terapêutico , Pesquisa Biomédica/ética , Brasil/epidemiologia , Doenças Transmissíveis Emergentes/tratamento farmacológico , Doenças Transmissíveis Emergentes/virologia , Regulamentação Governamental , Hospitalização/estatística & dados numéricos , Humanos , Mosquitos Vetores/virologia , Seleção de Pacientes/ética , Ensaios Clínicos Controlados Aleatórios como Assunto/ética , Sofosbuvir/uso terapêutico , Viremia/tratamento farmacológico , Febre Amarela/tratamento farmacológico , Febre Amarela/virologia , Vírus da Febre Amarela/efeitos dos fármacos , Vírus da Febre Amarela/fisiologia
4.
Vaccine ; 34(46): 5604-5611, 2016 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-27692770

RESUMO

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.


Assuntos
Portador Sadio/prevenção & controle , Infecções por Haemophilus/prevenção & controle , Haemophilus influenzae/isolamento & purificação , Nasofaringe/microbiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/isolamento & purificação , Brasil/epidemiologia , Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Estudos Transversais , Feminino , Infecções por Haemophilus/epidemiologia , Infecções por Haemophilus/microbiologia , Humanos , Programas de Imunização , Lactente , Modelos Logísticos , Masculino , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/microbiologia , Vacinas Pneumocócicas/administração & dosagem , Sorogrupo
5.
J Travel Med ; 21(5): 298-303, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24889210

RESUMO

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.


Assuntos
Surtos de Doenças , Vírus da Influenza B/isolamento & purificação , Influenza Humana/epidemiologia , Navios , Viagem , Adolescente , Adulto , Fatores Etários , Brasil/epidemiologia , Estudos de Casos e Controles , Feminino , Humanos , Controle de Infecções , Influenza Humana/prevenção & controle , Masculino , Pessoa de Meia-Idade
6.
Clin Vaccine Immunol ; 21(5): 636-40, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24599531

RESUMO

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.


Assuntos
Anticorpos Antibacterianos/sangue , Testes Diagnósticos de Rotina/métodos , Coqueluche/diagnóstico , Adolescente , Adulto , Idoso , Técnicas Bacteriológicas/métodos , Bordetella pertussis/genética , Bordetella pertussis/crescimento & desenvolvimento , Bordetella pertussis/imunologia , Bordetella pertussis/isolamento & purificação , Brasil , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Imunoglobulina G/sangue , Lactente , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular/métodos , Nasofaringe/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Adulto Jovem
7.
PLoS One ; 6(6): e20675, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21731621

RESUMO

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.


Assuntos
Meningites Bacterianas/microbiologia , Vigilância da População/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas de Tipagem Bacteriana , Brasil , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Contagem de Leucócitos , Masculino , Meningites Bacterianas/sangue , Meningites Bacterianas/líquido cefalorraquidiano , Pessoa de Meia-Idade , Análise Multivariada , Neisseria meningitidis/classificação , Neisseria meningitidis/genética , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Adulto Jovem
8.
Arq Bras Endocrinol Metabol ; 52(6): 1031-8, 2008 Aug.
Artigo em Português | MEDLINE | ID: mdl-18820815

RESUMO

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.


Assuntos
Apoptose , Proliferação de Células , Hipotireoidismo/metabolismo , Ovariectomia , Baço , Glândula Tireoide/metabolismo , Adenosina Trifosfatases/análise , Adenosina Trifosfatases/metabolismo , Animais , Antitireóideos , Caspase 3/análise , Caspase 3/metabolismo , Proteínas de Ligação a DNA/análise , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Feminino , Hipogonadismo/metabolismo , Hipotireoidismo/sangue , Hipotireoidismo/induzido quimicamente , Tecido Linfoide/metabolismo , Tecido Linfoide/patologia , Componente 7 do Complexo de Manutenção de Minicromossomo , Propiltiouracila , Ratos , Ratos Wistar , Baço/citologia , Baço/metabolismo , Baço/patologia , Glândula Tireoide/citologia , Tiroxina/sangue
9.
Arq. bras. endocrinol. metab ; 52(6): 1031-1038, ago. 2008. ilus, graf
Artigo em Português | LILACS | ID: lil-492935

RESUMO

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.


Assuntos
Animais , Feminino , Ratos , Apoptose , Proliferação de Células , Hipotireoidismo/metabolismo , Ovariectomia , Baço , Glândula Tireoide/metabolismo , Antitireóideos , Adenosina Trifosfatases/análise , Adenosina Trifosfatases/metabolismo , /análise , /metabolismo , Modelos Animais de Doenças , Proteínas de Ligação a DNA/análise , Proteínas de Ligação a DNA/metabolismo , Hipogonadismo/metabolismo , Hipotireoidismo/sangue , Hipotireoidismo/induzido quimicamente , Tecido Linfoide/metabolismo , Tecido Linfoide/patologia , Propiltiouracila , Ratos Wistar , Baço/citologia , Baço/metabolismo , Baço/patologia , Glândula Tireoide/citologia , Tiroxina/sangue
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