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1.
Artículo en Portugués | Sec. Est. Saúde SP, SESSP-CTDPROD, Sec. Est. Saúde SP | ID: biblio-1413046

RESUMEN

A integridade e a conduta responsável na pesquisa são essenciais para manter a excelência científica bem como a confiança pública na ciência. As instituições de ensino e pesquisa têm o dever de promover e monitorar a conduta responsável na pesquisa. Nas últimas décadas, muitas universidades e instituições de ensino e pesquisa, sociedades científicas e autoridades nacionais desenvolveram leis, regulamentos, guias e procedimentos específicos para direcionar ações no combate às más condutas. Além dos danos particulares causados aos autores, principalmente nos aspectos emocional e profissional, as más condutas científicas atingem diretamente a reputação, o prestígio e o nome das instituições envolvidas. O Instituto Adolfo Lutz considera essa temática de extrema relevância, e todo o trabalho de pesquisa referente ao estudo sobre integridade na pesquisa científica assim como as propostas de atuação institucional na promoção de uma cultura de integridade científica são relatados neste artigo.


Asunto(s)
Ciencia , Control Social Formal , Sociedades Científicas , Conducta
2.
Cell Rep ; 30(7): 2275-2283.e7, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-32075736

RESUMEN

Zika virus (ZIKV) has caused an explosive epidemic linked to severe clinical outcomes in the Americas. As of June 2018, 4,929 ZIKV suspected infections and 46 congenital syndrome cases had been reported in Manaus, Amazonas, Brazil. Although Manaus is a key demographic hub in the Amazon region, little is known about the ZIKV epidemic there, in terms of both transmission and viral genetic diversity. Using portable virus genome sequencing, we generated 59 ZIKV genomes in Manaus. Phylogenetic analyses indicated multiple introductions of ZIKV from northeastern Brazil to Manaus. Spatial genomic analysis of virus movement among six areas in Manaus suggested that populous northern neighborhoods acted as sources of virus transmission to other neighborhoods. Our study revealed how the ZIKV epidemic was ignited and maintained within the largest urban metropolis in the Amazon. These results might contribute to improving the public health response to outbreaks in Brazil.


Asunto(s)
Infección por el Virus Zika/virología , Virus Zika/genética , Brasil/epidemiología , Monitoreo Epidemiológico , Femenino , Genómica/métodos , Humanos , Masculino , Infección por el Virus Zika/epidemiología
3.
PLoS Negl Trop Dis ; 13(3): e0007065, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30845267

RESUMEN

BACKGROUND: Since its first detection in the Caribbean in late 2013, chikungunya virus (CHIKV) has affected 51 countries in the Americas. The CHIKV epidemic in the Americas was caused by the CHIKV-Asian genotype. In August 2014, local transmission of the CHIKV-Asian genotype was detected in the Brazilian Amazon region. However, a distinct lineage, the CHIKV-East-Central-South-America (ECSA)-genotype, was detected nearly simultaneously in Feira de Santana, Bahia state, northeast Brazil. The genomic diversity and the dynamics of CHIKV in the Brazilian Amazon region remains poorly understood despite its importance to better understand the epidemiological spread and public health impact of CHIKV in the country. METHODOLOGY/PRINCIPAL FINDINGS: We report a large CHIKV outbreak (5,928 notified cases between August 2014 and August 2018) in Boa vista municipality, capital city of Roraima's state, located in the Brazilian Amazon region. We generated 20 novel CHIKV-ECSA genomes from the Brazilian Amazon region using MinION portable genome sequencing. Phylogenetic analyses revealed that despite an early introduction of the Asian genotype in 2015 in Roraima, the large CHIKV outbreak in 2017 in Boa Vista was caused by an ECSA-lineage most likely introduced from northeastern Brazil. Epidemiological analyses suggest a basic reproductive number of R0 of 1.66, which translates in an estimated 39 (95% CI: 36 to 45) % of Roraima's population infected with CHIKV-ECSA. Finally, we find a strong association between Google search activity and the local laboratory-confirmed CHIKV cases in Roraima. CONCLUSIONS/SIGNIFICANCE: This study highlights the potential of combining traditional surveillance with portable genome sequencing technologies and digital epidemiology to inform public health surveillance in the Amazon region. Our data reveal a large CHIKV-ECSA outbreak in Boa Vista, limited potential for future CHIKV outbreaks, and indicate a replacement of the Asian genotype by the ECSA genotype in the Amazon region.


Asunto(s)
Fiebre Chikungunya/epidemiología , Virus Chikungunya/genética , Brotes de Enfermedades/prevención & control , Genoma Viral/genética , Zoonosis/epidemiología , Animales , Brasil/epidemiología , Fiebre Chikungunya/transmisión , Fiebre Chikungunya/virología , Virus Chikungunya/aislamiento & purificación , Monitoreo Epidemiológico , Humanos , Filogenia , Secuenciación Completa del Genoma , Zoonosis/transmisión , Zoonosis/virología
4.
Molecules ; 17(10): 12003-14, 2012 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-23085651

RESUMEN

More than 40% of the World population is at risk of contracting malaria, which affects primarily poor populations in tropical and subtropical areas. Antimalarial pharmacotherapy has utilised plant-derived products such as quinine and artemisinin as well as their derivatives. However, worldwide use of these antimalarials has caused the spread of resistant parasites, resulting in increased malaria morbidity and mortality. Considering that the literature has demonstrated the antimalarial potential of triterpenes, specially betulinic acid (1) and ursolic acid (2), this study investigated the antimalarial activity against P. falciparum chloroquine-sensitive 3D7 strain of some new derivatives of 1 and 2 with modifications at C-3 and C-28. The antiplasmodial study employed flow cytometry and spectrofluorimetric analyses using YOYO-1, dihydroethidium and Fluo4/AM for staining. Among the six analogues obtained, compounds 1c and 2c showed excellent activity (IC50 = 220 and 175 nM, respectively) while 1a and b demonstrated good activity (IC50 = 4 and 5 µM, respectively). After cytotoxicity evaluation against HEK293T cells, 1a was not toxic, while 1c and 2c showed IC50 of 4 µM and a selectivity index (SI) value of 18 and 23, respectively. Moreover, compound 2c, which presents the best antiplasmodial activity, is involved in the calcium-regulated pathway(s).


Asunto(s)
Antimaláricos/síntesis química , Antimaláricos/farmacología , Plasmodium falciparum/efectos de los fármacos , Triterpenos/síntesis química , Triterpenos/farmacología , Antimaláricos/toxicidad , Eritrocitos/efectos de los fármacos , Eritrocitos/parasitología , Células HEK293 , Humanos , Concentración 50 Inhibidora , Pruebas de Sensibilidad Parasitaria , Triterpenos Pentacíclicos , Triterpenos/toxicidad , Ácido Betulínico , Ácido Ursólico
5.
Malar J ; 11: 69, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22420332

RESUMEN

BACKGROUND: Plasmodium has a complex cell biology and it is essential to dissect the cell-signalling pathways underlying its survival within the host. METHODS: Using the fluorescence resonance energy transfer (FRET) peptide substrate Abz-AIKFFARQ-EDDnp and Fluo4/AM, the effects of extracellular ATP on triggering proteolysis and Ca²âº signalling in Plasmodium berghei and Plasmodium yoelii malaria parasites were investigated. RESULTS: The protease activity was blocked in the presence of the purinergic receptor blockers suramin (50 µM) and PPADS (50 µM) or the extracellular and intracellular calcium chelators EGTA (5 mM) and BAPTA/AM (25, 100, 200 and 500 µM), respectively for P. yoelii and P. berghei. Addition of ATP (50, 70, 200 and 250 µM) to isolated parasites previously loaded with Fluo4/AM in a Ca²âº-containing medium led to an increase in cytosolic calcium. This rise was blocked by pre-incubating the parasites with either purinergic antagonists PPADS (50 µM), TNP-ATP (50 µM) or the purinergic blockers KN-62 (10 µM) and Ip5I (10 µM). Incubating P. berghei infected cells with KN-62 (200 µM) resulted in a changed profile of merozoite surface protein 1 (MSP1) processing as revealed by western blot assays. Moreover incubating P. berghei for 17 h with KN-62 (10 µM) led to an increase in rings forms (82% ± 4, n = 11) and a decrease in trophozoite forms (18% ± 4, n = 11). CONCLUSIONS: The data clearly show that purinergic signalling modulates P. berghei protease(s) activity and that MSP1 is one target in this pathway.


Asunto(s)
Adenosina Trifosfato/metabolismo , Calcio/metabolismo , Plasmodium berghei/efectos de los fármacos , Plasmodium berghei/metabolismo , Plasmodium yoelii/efectos de los fármacos , Plasmodium yoelii/metabolismo , Proteolisis , Compuestos de Anilina/metabolismo , Péptidos/metabolismo , Transducción de Señal , Coloración y Etiquetado , Xantenos/metabolismo
6.
Int J Parasitol ; 41(3-4): 363-72, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21168413

RESUMEN

Malaria is still a major health problem in developing countries. It is caused by the protist parasite Plasmodium, in which proteases are activated during the cell cycle. Ca(2+) is a ubiquitous signalling ion that appears to regulate protease activity through changes in its intracellular concentration. Proteases are crucial to Plasmodium development, but the role of Ca(2+) in their activity is not fully understood. Here we investigated the role of Ca(2+) in protease modulation among rodent Plasmodium spp. Using fluorescence resonance energy transfer (FRET) peptides, we verified protease activity elicited by Ca(2+) from the endoplasmatic reticulum (ER) after stimulation with thapsigargin (a sarco/endoplasmatic reticulum Ca(2+)-ATPase (SERCA) inhibitor) and from acidic compartments by stimulation with nigericin (a K(+)/H(+) exchanger) or monensin (a Na(+)/H(+) exchanger). Intracellular (BAPTA/AM) and extracellular (EGTA) Ca(2+) chelators were used to investigate the role played by Ca(2+) in protease activation. In Plasmodium berghei both EGTA and BAPTA blocked protease activation, whilst in Plasmodium yoelii these compounds caused protease activation. The effects of protease inhibitors on thapsigargin-induced proteolysis also differed between the species. Pepstatin A and phenylmethylsulphonyl fluoride (PMSF) increased thapsigargin-induced proteolysis in P. berghei but decreased it in P. yoelii. Conversely, E64 reduced proteolysis in P. berghei but stimulated it in P. yoelii. The data point out key differences in proteolytic responses to Ca(2+) between species of Plasmodium.


Asunto(s)
Activación Enzimática/efectos de los fármacos , Eritrocitos/parasitología , Péptido Hidrolasas/metabolismo , Péptidos/farmacología , Plasmodium berghei/enzimología , Plasmodium yoelii/enzimología , Animales , Calcio/metabolismo , Calcio/farmacología , Señalización del Calcio , Transferencia Resonante de Energía de Fluorescencia , Monensina/farmacología , Nigericina/farmacología , Péptidos/química , Plasmodium berghei/efectos de los fármacos , Plasmodium yoelii/efectos de los fármacos , Tapsigargina/farmacología
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