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1.
Neotrop Entomol ; 52(6): 1005-1017, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37768508

RESUMO

Studying the nesting biology of wasp and bee species provides valuable insights into the ecology and evolution of these insects, shedding light on their ecological significance and aiding in their conservation efforts. Trypoxylon Latreille, 1796 is a genus of spider-hunting wasps that provisions their brood with paralyzed preys. This study focuses on aspects of nesting biology of Trypoxylon (Trypargilum) species such as sex ratio, sexual dimorphism, and morphometric variation at both inter- and intraspecific levels. The secondary sex ratio (SR) exhibited variation among species and populations. Males predominantly emerged from the first brood cells and from trap nests with smaller diameters. In comparison, females showed significantly larger body mass and linear wing measurements than males. Procrustes ANOVA values for centroid size (CS) and wing shape (SH) indicated significant differences in both wing size and shape among the five analyzed Trypoxylon species. Sexual dimorphism indices (SDI) derived from centroid size were found to be similar to those obtained from linear measurements, while SDI values based on body mass were significantly higher. Nests containing a greater number of cells tended to produce a larger number of higher-quality males and females. This observation, along with the lower coefficient of variation for female body size and high heritability, suggests that this trait may be subject to natural selection. Further studies that estimate the size of parents and their respective offspring are necessary to confirm the fitness advantage associated with larger female sizes in Trypoxylon species.


Assuntos
Razão de Masculinidade , Vespas , Masculino , Abelhas , Feminino , Animais , Caracteres Sexuais , Tamanho Corporal , Asas de Animais
2.
J Fungi (Basel) ; 8(8)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36012834

RESUMO

Inteins are genetic mobile elements that are inserted within protein-coding genes, which are usually housekeeping genes. They are transcribed and translated along with the host gene, then catalyze their own splicing out of the host protein, which assumes its functional conformation thereafter. As Prp8 inteins are found in several important fungal pathogens and are absent in mammals, they are considered potential therapeutic targets since inhibiting their splicing would selectively block the maturation of fungal proteins. We developed a target-based drug screening system to evaluate the splicing of Prp8 intein from the yeast pathogen Cryptococcus neoformans (CnePrp8i) using Saccharomyces cerevisiae Ura3 as a non-native host protein. In our heterologous system, intein splicing preserved the full functionality of Ura3. To validate the system for drug screening, we examined cisplatin, which has been described as an intein splicing inhibitor. By using our system, new potential protein splicing inhibitors may be identified and used, in the future, as a new class of drugs for mycosis treatment. Our system also greatly facilitates the visualization of CnePrp8i splicing dynamics in vivo.

3.
Food Res Int ; 149: 110657, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34600659

RESUMO

Imbalances in gut microbiota composition occur in individuals with autism spectrum disorder (ASD). The administration of probiotics, prebiotics, and synbiotics is emerging as a potential and promising strategy for regulating the gut microbiota and improving ASD-related symptoms. We first investigated the survival of the probiotics Limosilactobacillus (L.) reuteri and Bifidobacterium (B.) longum alone, mixed and combined with a galacto-oligosaccharide (GOS) under simulated gastrointestinal conditions. Next, we evaluated the impact of probiotics (L. reuteri + B. longum), prebiotic (GOS), and synbiotic (L. reuteri + B. longum + GOS) on gut microbiota composition and metabolism of children with ASD using an in vitro fermentation model (SHIME®). The combination of L. reuteri, B. longum, and GOS showed elevated gastrointestinal resistance. The probiotic, prebiotic, and synbiotic treatments resulted in a positive modulation of the gut microbiota and metabolic activity of children with ASD. More specifically, the probiotic treatment increased the relative abundance of Lactobacillus, while the prebiotic treatment increased the relative abundance of Bifidobacterium and decreased the relative abundance of Lachnoclostridium. Changes in microbial metabolism were associated with increased short-chain fatty acid concentrations and reduced ammonium levels, particularly in the prebiotic and synbiotic treatments.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Microbioma Gastrointestinal , Probióticos , Simbióticos , Criança , Humanos , Prebióticos
4.
AMB Express ; 8(1): 166, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30311091

RESUMO

The fermentation process is widely used in the industry for bioethanol production. Even though it is widely used, microbial contamination is unpredictable and difficult to control. The problem of reduced productivity is directly linked to competition for nutrients during contamination. Yeasts representing the Candida species are frequently isolated contaminants. Elucidating the behavior of a contaminant during the fermentation cycle is essential for combatting the contamination. Consequently, the aim of the current study was to better understand the functional and transcriptional behavior of a contaminating yeast Candida tropicalis. We used a global RNA sequencing approach (RNA-seq/MiSeq) to analyze gene expression. Genes with significantly repressed or induced expression, and related to the fermentations process, such as sugar transport, pyruvate decarboxylase, amino acid metabolism, membrane, tolerance to high concentrations of ethanol and temperatures, nutrient suppression), and transcription-linked processes, were identified. The expression pattern suggested that the functional and transcriptional behavior of the contaminating yeast during fermentation for bioethanol production is similar to that of the standard yeast Saccharomyces cerevisiae. In addition, the analysis confirmed that C. tropicalis is an important contaminant of the alcoholic fermentation process, generating bioethanol and viability through its tolerance to all the adversities of a fermentation process essential for the production of bioethanol. According on the gene expression profile, many of these mechanisms are similar to those of S. cerevisiae strains currently used for bioethanol production. These mechanisms can inform studies on antimicrobials, to combat yeast contamination during industrial bioethanol production.

5.
Rev. bras. entomol ; 53(1): 107-114, 2009. graf, tab
Artigo em Português | LILACS, Sec. Est. Saúde SP | ID: lil-511779

RESUMO

Vespas do gênero Trypoxylon apresentam comportamento solitário e aprovisionam seus ninhos de forma massiva com aranhas paralisadas. Algumas espécies utilizam cavidades preexistentes para nidificação, o que facilita sua amostragem e estudo. Neste trabalho, dados sobre a biologia de nidificação de quatro espécies de Trypoxylon (Trypargilum) - T. rogenhoferi, T. lactitarse, T. aurifrons e T. nitidum - são apresentados. As espécies foram amostradas por meio de ninhos-armadilha durante três anos em Araras e dois anos em Rifaina e São Carlos (São Paulo). As localidades de estudo foram subdivididas em sítios de amostragem. Foram obtidos 2.698 ninhos de himenópteros solitários, dos quais 2.268 foram fundados por espécies de Trypoxylon. Intensa atividade de nidificação foi observada principalmente na estação quente e chuvosa (outubro-março). Os ninhos-armadilha utilizados para nidificação pelas diferentes espécies apresentaram dimensões significativamente diferentes. A família de aranhas mais utilizada para aprovisionamento foi Araneidae; no entanto, as espécies de vespas diferiram quanto às espécies forrageadas. O principal parasitóide das quatro espécies foi Melittobia, mas indivíduos das famílias Chrysididae, Ichneumonidae, Chalcididae e Sarcophagidae também foram verificados. Observou-se que as espécies de Trypoxylon coexistem temporalmente e que nas três localidades cada espécie nidificou com maior freqüência em um sítio particular, sugerindo uma ocupação diferencial do habitat. A partição do habitat aparentemente homogêneo pode ser resultado de "competição aparente" mediada por inimigos naturais comuns.


Wasps of the genus Trypoxylon are solitary and females mass-provision their nests with paralyzed spiders. Some species use successfully trap-nests for nesting foundation, making easier their sampling and study. This paper reports data about nesting biology of four species of Trypoxylon (Trypargilum) - T. rogenhoferi, T. lactitarse, T. aurifrons and T. nitidum. These species were sampled by trap-nests during three years in Araras and two years in São Carlos and Rifaina (São Paulo). These areas were subdivided into sampling sites. A total of 2,698 nests of solitary hymenopterans were collected and most of them (2,268) were founded by Trypoxylon species. Nesting activity was higher in the warm, rainy season (October-March). The trap-nests used by the different species showed significantly different dimensions. Araneidae was the spider family mainly used for provision, but a species-specific provisioning was observed. The most important parasitoid of the four species was Melittobia, but adult chrysidids, ichneumonids, chalcidids and sarcophagids also attacked their nests. In the three areas, the different species of Trypoxylon coexist temporally but each of them built their nests frequently in a specific site. This result may suggest differential occupation of the habitat. This habitat partition of an apparently homogeneous area may be a result of an "apparent competition" shaped by shared natural enemies.


Assuntos
Animais , Masculino , Feminino , Comportamento de Nidação , Ecossistema , Vespas , Brasil , Estações do Ano
6.
Rev. bras. entomol ; 51(3): 369-376, jul.-set. 2007. graf, tab
Artigo em Inglês | LILACS | ID: lil-466120

RESUMO

The present study was carried out in three localities of the state of São Paulo, Brazil: Araras (Dec/03-Dec/06), São Carlos (Nov/04-Nov/06) and Rifaina (Jul/04-Dec/06). Trap-nests were distributed among sites in the sampling areas and were collected every 35 days. Data from 295 nests indicate that T. aurifrons is a multivoltine species, with higher rates of nest building and cell production in the warm, rainy season. The trap-nests used by the females ranged from 117 to 467 mm in length and 3.1 to 16.6 mm in diameter. All nests showed deep plugs and a vestibular cell was found in 37 percent of the complete nests. The number of cells per nest ranged from one to 12. Females were larger than males, emerged from longer cells and their cocoons were significantly larger. A secondary 1:1 sex ratio was found in Araras and Rifaina. No correlation was observed between the diameter of the trap-nest and sex ratio. Males were usually oviposited in the first brood cells. Male and female developmental time from egg to adult was longer in the cold, dry season. Trypoxylon aurifrons provisioned their nests mainly with orb-spiders from the family Araneidae. The most important mortality factor was the death of immature forms, probably due to development failure. The most important parasitoid was Melittobia sp.


Este estudo foi realizado em três localidades do estado de São Paulo: Araras (dez/03-dez/06), São Carlos (nov/04-nov/06) e Rifaina (jul/04-dez/06). Ninhos-armadilhas foram distribuídos em diferentes sítios das áreas amostradas e coletados a cada 35 dias. Dados de 295 ninhos mostraram que T. aurifrons é uma espécie multivoltina, com maiores taxas de nidificação e produção de células na estação quente e chuvosa. Os ninhos-armadilhas utilizados pelas fêmeas variaram de 117 a 467 mm de comprimento e de 3,1 a 16,6 mm de diâmetro. Todos os ninhos apresentaram parede de fundo e célula vestibular foi constatada em 37 por cento dos ninhos completos. O número de células por ninho variou de um a 12. Fêmeas emergiram de células e pupários maiores, sendo significantemente maiores que os machos. Razão sexual secundária igual a 1:1 foi observada em Araras e Rifaina. Não foi encontrada correlação significativa entre a razão sexual e o diâmetro do tubo. Machos foram encontrados principalmente nas primeiras células de cria. O tempo de desenvolvimento ovo-adulto foi mais longo na estação fria e seca. Trypoxylon aurifrons aprovisionou seus ninhos principalmente com aranhas da família Araneidae. O principal fator de mortalidade foi a interrupção do desenvolvimento das formas imaturas e o parasitóide mais freqüentemente encontrado foi Melittobia sp.


Assuntos
Animais , Masculino , Feminino , Ecossistema , Estágios do Ciclo de Vida , Comportamento de Nidação , Estações do Ano , Vespas/crescimento & desenvolvimento , Vespas/fisiologia , Brasil
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