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1.
Sci Eng Ethics ; 25(4): 1037-1055, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-29404974

RESUMO

In Brazil, the CNPq (National Council for Scientific and Technological Development) provides grants, funds and fellowships to productive scientists to support their investigations. They are ranked and categorized into four hierarchical levels ranging from PQ 1A (the highest) to PQ 1D (the lowest). Few studies, however, report and analyse scientific productivity in different sub-fields of Biomedical Sciences (BS), e.g., Biochemistry, Pharmacology, Biophysics and Physiology. In fact, systematic comparisons of productivity among the PQ 1 categories within the above sub-fields are lacking in the literature. Here, the scientific productivity of 323 investigators receiving PQ 1 fellowships (A to D levels) in these sub-fields of BS was investigated. The Scopus database was used to compile the total number of articles, citations, h-index values and authorship positions (first-, co- or last-listed author) in the most cited papers by researchers granted CNPq fellowships. We found that researchers from Pharmacology had the best performance for all of the parameters analysed, followed by those in Biochemistry. There was great variability in scientific productivity within the PQ 1A level in all of the sub-fields of BS, but not within the other levels (1B, 1C and 1D). Analysis of the most cited papers of PQ 1(A-D) researchers in Pharmacology revealed that the citations of researchers in the 1C and 1D levels were associated with publications with their senior supervisors, whereas those in the 1B level were less connected with their supervisors in comparison to those in 1A. Taken together, these findings suggest that the scientific performance of PQ 1A researchers in BS is not homogenous. In our opinion, parameters such as the most cited papers without the involvement of Ph.D. and/or post-doctoral supervisors should be used to make decisions regarding any given researcher's fellowship award level.


Assuntos
Bibliometria , Disciplinas das Ciências Biológicas/classificação , Pesquisa Biomédica/classificação , Pesquisa Biomédica/economia , Pesquisa Biomédica/normas , Pesquisadores/classificação , Apoio à Pesquisa como Assunto , Autoria/normas , Disciplinas das Ciências Biológicas/economia , Brasil , Bases de Dados Bibliográficas , Eficiência , Feminino , Humanos , Masculino , Pesquisadores/economia , Pesquisadores/normas
2.
EXCLI J ; 16: 566-582, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28694758

RESUMO

Lantana camara, the widely studied species, and L. montevidensis, the less studied species of the genus Lantana are both used in traditional medicine for the same purpose (anti-asthma, anti-ulcer, anti-tumor, etc). However, little is known about the toxicity of L. montevidensis and there is limited information on its chemical constituents. Here, we investigated for the first time the genotoxicity and cytotoxicity of the ethanolic (EtOH) and aqueous extracts from the leaves of Lantana montevidensis in human leukocytes, as well as their possible interaction with human erythrocyte membranes in vitro. The antioxidant activities of both extracts were also investigated in chemical and biological models. Treatment of leukocytes with EtOH or aqueous extracts (1-480 µg/mL) did not affect DNA damage index, but promoted cytotoxicity at higher concentrations (240-480 µg/mL). Both extracts did not modify the osmotic fragility of human erythrocytes. The extracts scavenged DPPH radical and prevented Fe2+-induced lipid peroxidation in rat's brain and liver homogenates, and this was likely not attributed to Fe (II) chelation. The HPLC analysis of the extracts showed different amounts of polyphenolic compounds (isoquercitrin, gallic acid, catechin, ellagic acid, apigenin, kaempferol, caffeic acid, rutin, quercitrin, quercetin, chlorogenic acid, luteolin) that may have contributed to these effects. These results supported information on the functional use of L. montevidensis in folk medicine.

3.
Food Chem Toxicol ; 44(5): 662-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16289284

RESUMO

The present study was conducted to evaluate the toxicity of the exposure to diphenyl diselenide [(PhSe)2] and diphenyl ditelluride [(PhTe)2] on reproductive system in Wistar rats. Adult male rats were exposed intraperitonealy (acute) or subcutaneously (sub-chronic, during 4 or 8 weeks) to (PhSe)2 or (PhTe)2 prior to mating. A number of biochemical parameters in rat testes were examined, such as delta-aminolevulinate dehydratase (delta-ALA-D) activity, lipid peroxidation, glycogen content and components of the antioxidant defenses (superoxide dismutase (SOD) activity and ascorbic acid concentration). Furthermore, a possible effect on fertility and reproductive performance in male rats were studied. Sperm counts of caudal epididymis were also evaluated. No lethality was noted in any group. Reduction on body weight in rats which received (PhTe)2 was only evidenced in acute exposure, while (PhSe)2-exposed rats presented significant loss of body weight in acute and 4 week-exposure. Mating and fertility indexes were not affected after acute and sub-chronic exposure. Regarding other parameters studied, except for a decrease in testes glycogen content in acutely (PhSe)2-treated group, no alterations were found in treated groups. Sperm counts of rats treated acutely and sub-chronically were unaffected by drugs exposure. Histological evaluation revealed no modification on testicular tissue in rats exposed to (PhSe)2 and (PhTe)2. The results suggest the absence of the male reproductive toxicity induced by (PhSe)2 and (PhTe)2 administered intraperitonealy (acute) or subcutaneously (sub-chronical) to adult rats Wistar.


Assuntos
Derivados de Benzeno/toxicidade , Fertilidade/efeitos dos fármacos , Compostos Organometálicos/toxicidade , Compostos Organosselênicos/toxicidade , Reprodução/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Ácido Ascórbico/metabolismo , Peso Corporal/efeitos dos fármacos , Feminino , Glicogênio/metabolismo , Injeções Intraperitoneais , Injeções Subcutâneas , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Sintase do Porfobilinogênio/metabolismo , Gravidez , Ratos , Ratos Wistar , Contagem de Espermatozoides , Superóxido Dismutase/metabolismo , Testículo/patologia , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica
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