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631.
Simone Carradori Bruna Bizzarri Paola Chimenti Celeste De Monte Paolo Guglielmi 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):746-758
We designed and synthesised novel N-substituted 1,3-thiazolidin-4-one derivatives for the evaluation of their anti-Toxoplasma gondii efficacy. This scaffold was functionalised both at the N1-hydrazine portion with three structurally different moieties and at the lactam nitrogen with substituted benzyl groups selected on the basis of our previous structure-activity relationships studies. Using three different assay methods, the compounds were assessed in vitro to determine both the levels of efficacy against the tachyzoites of T. gondii (IC50?=?5–148?μM), as well as any evidence of cytotoxicity towards human host cells (TD50?=?68 to ≥320?μM). Results revealed that ferrocene-based thiazolidinones can possess potent anti-tachyzoite activity (TI =2–64). 相似文献
632.
Ktia Regina Carvalho de Assis Marcelo Sady Plcido Ladeira Roberta C.A. Bueno Bruna F. dos Santos Ivete Dalben Daisy Maria Favero Salvadori 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2009,679(1-2):72-78
Tobacco smoke contains a large number of substances known to induce DNA damage and to be hazardous to human health. Several reviews and meta-analyses have reported an association between maternal or paternal smoking habits and genetic-related diseases, such as cancer, in children. The aim of the present study was to evaluate the level of DNA damage in lymphocytes of active- and passive-smoking mothers and in their newborns, using the comet assay. A total of 40 active smokers, 40 passive smokers, and 40 non-smokers, and their respective newborns, were evaluated. The active smokers presented a statistically significant increase of DNA damage when compared to the non-smokers and passive-smokers. No significant difference was observed between passive and non-smoking women. Similar results were detected in newborns. Those born to active-smoking mothers presented higher levels of DNA damage than those from passive- and non-smoking mothers. Additionally, no significant difference was detected between newborns from non-smoking and passive-smoking mothers. Also, no statistically significant difference in DNA damage was observed between mothers and their respective newborns, and a positive correlation in the level of DNA damage was detected between them. Logistic regression analyses showed positive associations between DNA damage, spontaneous abortion and smoking status. In conclusion, our data indicate that tobacco exposure during pregnancy has genotoxic effects for both mother and child, and it can be considered an important risk factor for childhood cancer or other genetic-related diseases. 相似文献
633.
Christophe V. W. Seppey Léa Cabrol Frederic Thalasso Laure Gandois Céline Lavergne Karla Martinez-Cruz Armando Sepulveda-Jauregui Polette Aguilar-Muñoz María Soledad Astorga-España Rolando Chamy Bruna Martins Dellagnezze Claudia Etchebehere Gilberto J. Fochesatto Oscar Gerardo-Nieto Andrés Mansilla Alison Murray Maxime Sweetlove Nikita Tananaev Roman Teisserenc Alexander T. Tveit Anton Van de Putte Mette M. Svenning Maialen Barret 《Environmental microbiology》2023,25(12):3364-3386
Methane-cycling is becoming more important in high-latitude ecosystems as global warming makes permafrost organic carbon increasingly available. We explored 387 samples from three high-latitudes regions (Siberia, Alaska and Patagonia) focusing on mineral/organic soils (wetlands, peatlands, forest), lake/pond sediment and water. Physicochemical, climatic and geographic variables were integrated with 16S rDNA amplicon sequences to determine the structure of the overall microbial communities and of specific methanogenic and methanotrophic guilds. Physicochemistry (especially pH) explained the largest proportion of variation in guild composition, confirming species sorting (i.e., environmental filtering) as a key mechanism in microbial assembly. Geographic distance impacted more strongly beta diversity for (i) methanogens and methanotrophs than the overall prokaryotes and, (ii) the sediment habitat, suggesting that dispersal limitation contributed to shape the communities of methane-cycling microorganisms. Bioindicator taxa characterising different ecological niches (i.e., specific combinations of geographic, climatic and physicochemical variables) were identified, highlighting the importance of Methanoregula as generalist methanogens. Methylocystis and Methylocapsa were key methanotrophs in low pH niches while Methylobacter and Methylomonadaceae in neutral environments. This work gives insight into the present and projected distribution of methane-cycling microbes at high latitudes under climate change predictions, which is crucial for constraining their impact on greenhouse gas budgets. 相似文献
634.
Summary Biochemical properties of cytoplasmic and mitochondrial isozymes of isocitrate dehydrogenase from DBA/2J mice were compared under various experimental conditions. These included Km determinations, coenzyme specificity, pH dependence, urea, iodoacetate and thermal inactivation and fluorescence titration studies. From these comparative studies each isozyme was found to have distinct coenzyme specificity, thermal stability and sensitivity to alkylation. In the case of the cytoplasmic isozyme, both NADP+ and isocitrate protect the enzyme against thermal denaturation but not iodoacetate inactivation. On the contrary, neither NADP+ nor isocitrate protects the mitochondrial enzyme against thermal or iodoacetate inactivation. Both isozymes exhibit similar fluorescence properties. NADP+ and NADPH, but not isocitrate, cause quenching of protein fluorescence. Enhancement of coenzyme fluorescence and protein energy transfer was observed when either isozyme was added to NADPH solutions. Further addition of isocitrate or isocitrate-Mg++ to a NADPH-enzyme solution caused a decrease of the enhancement of coenzyme fluorescence and protein energy transfer, but not quenching of protein fluorescence, indicating the formation of a ternary complex. This observation precludes the mechanism of mutual exclusion between NADPH and isocitrate in the active site of the enzyme.Abbreviations used IDH
isocitrate dehydrogenase
- NHDP+
nicotinamide-hypoxanthine dinucleotide phosphate
- TNADP+
thionicotinamide-adenine dinucoleotide phosphate
- AcPyADP+
3-acetylpyridine-adenine dinucleotide phosphate
NIH Visiting Fellow. 相似文献
635.
Rodrigo Nunes Rodrigues-da-Silva Josué da Costa Lima-Junior Bruna de Paula Fonseca e Fonseca Paulo Renato Zuquim Antas Arlete Baldez Fabio Luiz Storer Fátima Santos Dalma Maria Banic Joseli de Oliveira-Ferreira 《Memórias do Instituto Oswaldo Cruz》2014,109(2):154-162
Haematological and cytokine alterations in malaria are a broad and controversial
subject in the literature. However, few studies have simultaneously evaluated various
cytokines in a single patient group during the acute and convalescent phases of
infection. The aim of this study was to sequentially characterise alterations in
haematological patters and circulating plasma cytokine and chemokine levels in
patients infected with Plasmodium vivax or Plasmodium falciparum from a Brazilian
endemic area during the acute and convalescent phases of infection. During the acute
phase, thrombocytopaenia, eosinopaenia, lymphopaenia and an increased number of band
cells were observed in the majority of the patients. During the convalescent phase,
the haematologic parameters returned to normal. During the acute phase, P. vivax and
P. falciparum patients had significantly higher interleukin (IL)-6, IL-8, IL-17,
interferon-γ, tumour necrosis factor (TNF)-α, macrophage inflammatory protein-1β and
granulocyte-colony stimulating factor levels than controls and maintained high levels
during the convalescent phase. IL-10 was detected at high concentrations during the
acute phase, but returned to normal levels during the convalescent phase. Plasma
IL-10 concentration was positively correlated with parasitaemia in P. vivax and P.
falciparum-infected patients. The same was true for the TNF-α concentration in P.
falciparum-infected patients. Finally, the haematological and cytokine profiles were
similar between uncomplicated P. falciparum and P. vivax infections. 相似文献
636.
Teixeira Fernanda Cardoso de Mattos Bruna da Silveira Mello Julia Eisenhardt de Cardoso Juliane Spohr Luiza Luduvico Karina Pereira Soares Mayara Sandrielly Pereira Carvalho Fabiano Barbosa Gutierres Jessie Martins Oliveira Campello Felix Anelize de Stefanello Francieli Moro Spanevello Roselia Maria 《Neurochemical research》2022,47(2):446-460
Neurochemical Research - This study investigated the effects of inosine on memory acquisition and consolidation, cholinesterases activities, redox status and Na+, K+-ATPase activity in a rat model... 相似文献
637.
Arboreal primates use loud vocalisations to transmit information in densely vegetated habitats. These vocalisations are likely to show adaptations to increase their propagation and to transmit information. Golden-backed uakaris, Cacajao melanocephalus, emit a loud vocalization termed the “tchó” call, which seems to function as a contact call and encodes information on the individual signaler and behavioural context. Because the call is often used for communication over relatively large distances, we were interested in its propagation in the wild. The aim of the present study was to investigate the degradation patterns of the tchó call in the flooded igapó forest. We examined via playback experiments how the acoustic parameters of this call changed with increasing distance from the playback speaker. We broadcast 12 tchó calls and rerecorded them along a transect at distances of 10, 20, 40, 80 and 160?m from the speaker in two igapó forest patches in Jaú National Park, Amazonas, Brazil. At 160?m from the speaker, the tchó call degraded in both patches and was barely recordable. Up to a distance of 80?m, the bandwidth and number of harmonics in the call decreased with increasing distance, while the lowest frequency increased. The highest frequency (HF) did not gradually decrease with increasing distance. However, when we compared the HF at distances of 10 and 80?m, we could see a clear decrease in this parameter. Call duration increased compared with the broadcast signal up to 40?m because of reverberation, but decreased at 80?m as the weaker echoes of the call attenuated. These changes may reveal information about the signaler’s distance during signal transmission. The frequency of maximum energy (FME) of the tchó call decreased significantly when comparing recordings made at 10 and 80?m. Nevertheless, it did not show a consistent and gradual decrease with increasing rerecording distance (at least up to 80?m). FME remained relatively stable (±50?Hz on average, at least up to 80?m) when compared to the other call parameters, suggesting that the tchó call may be adapted to transmit information with some efficiency throughout the igapó forest. 相似文献
638.
639.
Almeida Saá Antonella C. Crivellaro Marcelo S. Winter Bruna B. Pereira Grazyelle R. Bercovich Manuel Vivanco Horta Paulo A. Bastos Eduardo O. Schubert Nadine 《Coral reefs (Online)》2020,39(1):99-117
Coral Reefs - The impact of invasive species has been increasing in recent decades due to globalization, threatening marine biodiversity. Tubastraea spp. (sun corals) have been spreading worldwide,... 相似文献
640.
Infection by pathogenic microorganisms is a source of biological stress in plants. Understanding the interaction between plants
and microbial infection at molecular level might contribute to our understanding for the effective control of the disease.
Here, we isolated a novel putative receptor kinase-like protein (Citrus limon P5) that is the first Lec-receptor kinase-like protein isolated in lemon during a pathogen infection. C. limon P5 cDNA fragment was detected by differential display assay in C. limon during Capnodium citri (sooty mold) infection. The deduced amino acid sequence of P5 full-length cDNA revealed a 83% sequence homology with a receptor
kinase-like protein from Arabidopsis thaliana characterized by a N-terminal lectin domain and C-terminal serine/threonine conserved domain. The inhibition of the pathogen-responsive
P5 by the protein kinase inhibitor staurosporine and by a mitogen-activated protein kinase inhibitor (PD 98059) indicated
a defense mechanism in C. limon against pathogens mediated via signal transduction pathway. To our knowledge, this is the first evidence that C. limon uses this putative defense mechanism against pathogens. The role of this protein is discussed as a starting point to understanding
the molecular mechanisms in the C. limon in response to C. citri infection. 相似文献