Antifungal and anti-biofilm activity of designed derivatives from kyotorphin

© 2019 British Mycological Society. Published by Elsevier Ltd. All rights reserved.Kyotorphin (KTP, l-tyrosyl-l-arginine) is an endogenous analgesic neuropeptide first isolated from bovine brain in 1979. Previous studies have shown that kyotorphins possess anti-inflammatory and antimicrobial activity. Six kyotorphins—KTP-NH2, KTP–NH2–DL, ibuprofen-conjugated KTP (IbKTP), IbKTP-NH2, N-methyl-D-Tyr-L-Arg, and N-methyl-L-Tyr-D-Arg—were designed and synthesized to improve lipophilicity and resistance to enzymatic degradation. This study assessed the antimicrobial and antibiofilm activity of these peptides. The antifungal activity of kyotorphins was determined in representative strains of Candida species, including Candida albicans ATCC 10231, Candida krusei ATCC 6258, and six clinical isolates—Candida dubliniensis 19-S, Candida glabrata 217-S, Candida lusitaniae 14-S, Candida novergensis 51-S, Candida parapsilosis 63, and Candida tropicalis 140-S—obtained from the oral cavity of HIV-positive patients. The peptides were synthesized by standard solution or solid-phase synthesis, purified by RP-HPLC (purity >95 %), and characterized by nuclear magnetic resonance. The results of the broth microdilution assay and scanning electron microscopy showed that IbKTP-NH2 presented significant antifungal activity against Candida strains and antibiofilm activity against the clinical isolates. The absence of toxic activity and survival after infection was assessed after injecting the peptide in larvae of Galleria mellonella as experimental infection model. Furthermore, IbKTP-NH2 had strong antimicrobial activity against multidrug-resistant bacteria and fungi and was not toxic to G. mellonella larvae up to a concentration of 500 mM. These results suggest that IbKTP-NH2, in addition to its known effect on cell membranes, can elicit a cellular immune response and, therefore, is promising for biomedical application.This research was supported by FAPESP (Grant No. 2017/00032-0). This article is also part of the Fungal Adaptation to Hostile Challenges special issue for the third International Symposium on Fungal Stress (ISFUS), which is supported by the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) (Grant No. 2018/20571-6) and the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) (Grant No. 88881.289327/2018-01).info:eu-repo/semantics/publishedVersio

Caracterização de uma liga de magnésio processada via laminação assimétrica / Characterization of a magnesium alloy processed by asymmetric rolling

Este estudo teve como objetivo avaliar a influência da assimetria durante o processo de laminação com reduções de 10% e 20% na espessura empregada à liga de magnésio AZ31, do ponto de vista microestrutural e propriedade mecânica. Diversos estudos têm sido realizados nas ligas de magnésio visando adquirir melhores propriedades mecânicas, sobretudo conformabilidade, pois esta é uma das principais limitações encontradas na liga. Neste trabalho são apresentados os resultados microestruturais e mecânicos para amostras processadas por laminação simétrica e assimétrica nas reduções de 10% e 20% nas temperaturas ambiente, 100 °C, 200 °C, 300 °C e 400 °C. Foi observado que todas as amostras submetidas ao processo de laminação assimétrica apresentaram um valor maior de dureza em relação àquelas laminadas simetricamente. Também, observou-se que as amostras laminadas a 400°C apresentaram grãos refinados, podendo ser um indício de que tenha ocorrido a recristalização. Uma vez que este efeito também pôde ser observado a 300 °C, porém exclusivamente para a amostra laminada assimetricamente, este resultado pode estar relacionado ao processo assimétrico promover uma maior deformação no material

LEVANTAMENTO DE LAGARTAS (LEPIDOPTERA) NO PARQUE RECREATIVO SUCUPIRA E COMPARAÇÃO DE INTERAÇÕES COM PLANTAS HOSPEDEIRAS NO CERRADO DO BRASIL CENTRAL

Brazilian Cerrado is considered an important area for environment conservation, due to its high species’ richness and endemism. Nevertheless, this biome has been intensely destroyed because of its potential for agriculture – of plants and animals. For this reason, it is important to have tools to evaluate quickly the effects of such threats on biological diversity. A type of approach that has been investigated lately is using ecological interactions, since species exclusion or a change on its abundance caused by human disturbance may cause co-extinctions. Therefore, getting to know different aspects on interactions between species may be the fi rst step to understand the stability of an ecosystem after such threats. So, in the present work the utilization of fi ve plant species by caterpillars (Lepidoptera) was surveyed in a urban park at Planaltina, Federal District. Since there is quite an extensive information on the ecology of these animals at the region, this work aimed to compare the amount of interactions between caterpillars and plants at the urban park with data in the literature, considering the situation at wellpreserved areas. Besides, considering the level of integrity on interactions, it was also aimed to suggest how human visitation at the park threatens caterpillars. To this purpose, caterpillars were surveyed at fi ve host plants, Byrsonima coccolobifolia, Kielmeyera sp., Himathantus obovatus, Pouteria ramifl ora e Roupala montana, in June, when caterpillars are more abundant in the fi eld. Using the community structure that was found, it was estimated species richness at each host plant. It was found 32 caterpillar species. In four out of fi ve studied plants, the number of estimated species is not much lower than the ones at preserved areas. Only in R. montana it was not found a species richness as high as expected, by considering literature data. This work reinforces the application of rapid surveys for conservation actions and suggests that other groups of organism should be considered in the future to confi rm the preservation pattern of study area.O bioma Cerrado é considerado importante por abrigar alta riqueza de espécies e endemismos. No entanto, este vem sofrendo uma intensa destruição, devido ao seu potencial agrícola e pecuário. Por esse motivo, é importante que se tenham ferramentas para avaliar, de forma rápida, os efeitos dessas pressões na integridade da diversidade biológica. Uma das abordagens que vem sendo investigada é a de considerar interações ecológicas, porque a exclusão e/ou alteração da abundância de espécies, causada pela perturbação, podem promover co-extinção destas. Assim, conhecer diferentes características de interações entre espécies pode ser o primeiro passo para acessar a estabilidade do ecossistema frente a tais perturbações. Nesse sentido, no presente trabalho foi levantada a utilização de cinco espécies de plantas hospedeiras por lagartas (Lepidoptera), em um Parque urbano de Planaltina, no Distrito Federal. Uma vez que existe uma grande quantidade de informação ecológica sobre esses animais no Distrito Federal, o objetivo principal deste trabalho foi o de comparar a quantidade de interações lagartas x plantas encontradas no Parque urbano com a descrita na literatura científi ca para áreas mais preservadas. Além disso, através dessa comparação, considerando a integridade das interações, objetivou-se propor o grau de distúrbio causado pela visitação humana no Parque. Para isso, durante o mês de junho, quando há maior abundância de lagartas no campo, foi feito um levantamento das mesmas nas plantas Byrsonima coccolobifolia, Kielmeyera sp., Himathantus obovatus, Pouteria ramifl ora e Roupala montana. A partir da estrutura da comunidade de Lepidoptera encontrada, foi estimada a riqueza total de espécies de lagartas em cada planta hospedeira. Durante o levantamento, foram encontradas 32 espécies de lagartas no total. Em quatro espécies de plantas, os resultados obtidos pelas estimativas de riqueza de espécies indicaram que o número de interações encontradas no Parque urbano não é tão menor do que o encontrado nas áreas preservadas. Somente em R. montana foi encontrada uma riqueza de espécies abaixo à esperada, de acordo com as comunidades descritas na literatura. Sob esse aspecto, sugere-se que o Parque parece estar em bom estado de conservação. O presente trabalho reforça a aplicação de levantamentos rápidos em práticas de conservação e sugere a inclusão de novos grupos de organismos no futuro, para confi rmar o padrão sobre o grau de preservação da área de estudo

Beckwith-Wiedemann syndrome mimicking the classical form of congenital adrenal hyperplasia in newborn screening

SUMMARY Beckwith-Wiedemann syndrome (BWS) is a common genetic congenital disease characterized by somatic overgrowth and its broad clinical spectrum includes pre- and post-natal macrosomia, macroglossia, visceromegaly, increased risk of neonatal hypoglycemia, and development of embryonic tumors. BWS occurs due to genetic/epigenetic changes involving growth-regulating genes, located on region 11p15, with an important genotype-phenotype correlation. Congenital adrenal hyperplasia (CAH) comprises a spectrum of autosomal recessive diseases presenting a variety of clinical manifestations due to a deficiency in one of the enzymes involved in cortisol secretion. Early diagnosis based on newborn screening prevents the adrenal crisis and early infant death. However, high 17-hydroxyprogesterone (17-OHP) levels can occur in newborns or premature infants without CAH, in situations of stress due to maternal or neonatal factors. Here, we report new cases of false-positive diagnosis of 21-hydroxylase deficiency during newborn screening – two girls and one boy with BWS. Methylation-specific multiplex ligation-dependent probe amplification revealed a gain of methylation in the H19 differentially methylated region. Notably, all three cases showed a complete normalization of biochemical changes, highlighting the transient nature of these hormonal findings that imitate the classical form of CAH. This report sheds light on a new cause of false-positive 21-hydroxylase deficiency diagnosis during newborn screening: Beckwith-Wiedemann syndrome

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio