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81.
Cintia D. L. Martins Cintia Lhullier Fernanda Ramlov José Carlos Simonassi Lidiane P. Gouvea Mauricio Noernberg Marcelo Maraschin Pio Colepicolo Jason M. Hall-Spencer Paulo A. Horta 《Journal of applied phycology》2014,26(5):2037-2045
The assessment of human impacts on marine ecosystems is usually done by assessing changes in species diversity and abundance. Here, we add to this approach the assessment of primary and secondary metabolites from macroalgal communities in urban and protected areas in south Brazil and investigate whether the chemical diversity of marine macroalgae is affected by environmental changes, such as those caused by coastal urbanization, through the use of thin-layer chromatography. Additionally, we compare the chemical and biological diversity of macroalgal communities within urban and undeveloped sites along the southern Brazilian coast. Coastlines within protected areas had greater species richness and higher amounts of substances such as chlorophylls, carotenoids and lipids as well as a greater chemical diversity than coasts subjected to multiple stressors from urbanization. We conclude that the composition and abundance of primary and secondary metabolites provide useful additional information about the ecological status of coastal environments and improve our understanding of the effects of coastal biodiversity loss due to coastal urbanization. 相似文献
82.
Purification,characterization and partial sequence of a pro‐inflammatory lectin from seeds of Canavalia oxyphylla Standl. & L. O. Williams
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Mayara Q. Santiago Cintia C. F. Leitão Francisco N. Pereira‐Junior Vanir R. Pinto‐Junior Vinicius J. S. Osterne Claudia F. Lossio João B. Cajazeiras Helton C. Silva Francisco V. S. Arruda Livia P. Pereira Ana M. S. Assreuy Kyria S. Nascimento Celso S. Nagano Benildo S. Cavada 《Journal of molecular recognition : JMR》2014,27(3):117-123
Recent studies have shown that lectins are promising tools for use in various biotechnological processes, as well as studies of various pathological mechanisms, isolation, and characterization of glycoconjugates and understanding the mechanisms underlying pathological mechanisms conditions, including the inflammatory response. This study aimed to purify, characterize physicochemically, and predict the biological activity of Canavalia oxyphylla lectin (CoxyL) in vitro and in vivo. CoxyL was purified by a single‐step affinity chromatography in Sephadex® G‐50 column. Sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that the pure lectin consists of a major band of 30 kDa (α‐chain) and two minor components (β‐chain and γ‐chain) of 16 and 13 kDa, respectively. These data were further confirmed by electrospray ionization mass spectrometry, suggesting that CoxyL is a typical ConA‐like lectin. In comparison with the average molecular mass of α‐chain, the partial amino acid sequence obtained corresponds to approximately 45% of the total CoxyL sequence. CoxyL presented hemagglutinating activity that was specifically inhibited by monosaccharides (D‐glucose, D‐mannose, and α‐methyl‐D‐mannoside) and glycoproteins (ovalbumin and fetuin). Moreover, CoxyL was shown to be thermostable, exhibiting full hemagglutinating activity up to 60°C, and it was pH‐sensitive for 1 h, exhibiting maximal activity at pH 7.0. CoxyL caused toxicity to Artemia nauplii and induced paw edema in rats. This biological activity highlights the importance of lectins as important tools to better understand the mechanisms underlying inflammatory responses. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
83.
Ana Luiza Freire Cintia Lacerda Ramos Euziclei Gonzaga de Almeida Whasley Ferreira Duarte Rosane Freitas Schwan 《World journal of microbiology & biotechnology》2014,30(2):567-577
Yakupa is a traditional non-alcoholic cassava beverage produced by Brazilian Amerindians. In this work the microbial dynamics and metabolites involved in yakupa fermentation were investigated by PCR-denaturing gradient gel electrophoresis and chromatography analysis, respectively. The lactic acid bacteria (LAB) population was higher than yeast in the beginning of fermentation (5 log CFU mL?1 and 3 log CFU mL?1, respectively) and after 36 h both population increased reaching 7 log CFU mL?1, remaining constant until 60 h. Culture dependent and independent methods in combination identified the bacteria Lactobacillus fermentum, L. plantarum, Weissela cibaria and W. confusa, and yeasts Saccharomyces cerevisiae and Pichia kudriavzevii. Maltose (41.2 g L?1), ethanol (6.5 g L?1) and lactic acid (7.8 g L?1) were the most abundant compounds identified by high performance liquid chromatography. Aldehydes, acids, alcohols and esters were identified by gas chromatography flame ionization detection. By the metabolites and PCA analysis we may assign the beverage’s flavor to the microbial metabolism. Heterolactic LAB and S. cerevisiae dominated the yakupa fermentation, being responsible for the organoleptic characteristics of the final product. This is the first time that the microbial dynamics and physicochemical parameters were investigated in the yakupa beverage and it may contribute to the future selection of starter cultures to perform yakupa fermentations. 相似文献
84.
Cintia Ferreira Marinho Elzinandes Leal Azeredo Amanda Torrentes-Carvalho Alessandro Marins-Dos-Santos Claire Fernandes Kubelka Luiz José de Souza Rivaldo Venancio Cunha Luzia Maria de-Oliveira-Pinto 《PloS one》2014,9(7)
In dengue virus (DENV) infection, complement system (CS) activation appears to have protective and pathogenic effects. In severe dengue fever (DF), the levels of DENV non-structural-1 protein and of the products of complement activation, including C3a, C5a and SC5b-9, are higher before vascular leakage occurs, supporting the hypothesis that complement activation contributes to unfavourable outcomes. The clinical manifestations of DF range from asymptomatic to severe and even fatal. Here, we aimed to characterise CS by their receptors or activation product, in vivo in DF patients and in vitro by DENV-2 stimulation on monocytes. In comparison with healthy controls, DF patients showed lower expression of CR3 (CD11b), CR4 (CD11c) and, CD59 on monocytes. The DF patients who were high producers of SC5b-9 were also those that showed more pronounced bleeding or vascular leakage. Those findings encouraged us to investigate the role of CS in vitro, using monocytes isolated from healthy subjects. Prior blocking with CR3 alone (CD11b) or CR3 (CD11b/CD18) reduced viral infection, as quantified by the levels of intracellular viral antigen expression and soluble DENV non-structural viral protein. However, we found that CR3 alone (CD11b) or CR3 (CD11b/CD18) blocking did not influence major histocompatibility complex presentation neither active caspase-1 on monocytes, thus probably ruling out inflammasome-related mechanisms. Although it did impair the secretion of tumour necrosis factor alpha and interferon alpha. Our data provide strategies of blocking CR3 (CD11b) pathways could have implications for the treatment of viral infection by antiviral-related mechanisms. 相似文献
85.
Alexandre Medeiros do Carmo Fabiana Maria Santos Carmen Lucia Ortiz-Agostinho Iêda Nishitokukado Cintia S. Frota Flavia Ubeda Gomes André Zonetti de Arruda Leite Claudio Sérgio Pannuti Lucy Santos Vilas Boas Magaly Gemio Teixeira Aytan Miranda Sipahi 《PloS one》2014,9(11)
Background
Cytomegalovirus is highly prevalent virus and usually occurs in immunocompromised patients. The pathophysiology and treatment of inflammatory bowel disease often induce a state of immunosuppression. Because this, there are still doubts and controversies about the relationship between inflammatory bowel disease and cytomegalovirus.Aim
Evaluate the frequency of cytomegalovirus in patients with inflammatory bowel disease and identify correlations.Methods
Patients with inflammatory bowel disease underwent an interview, review of records and collection of blood and fecal samples. The search for cytomegalovirus was performed by IgG and IgM blood serology, by real-time PCR in the blood and by qualitative PCR in feces. Results were correlated with red blood cell levels, C-reactive protein levels, erythrocyte sedimentation rates and fecal calprotectin levels for each patient.Results
Among the 400 eligible patients, 249 had Crohn''s disease, and 151 had ulcerative colitis. In the group of Crohn''s disease, 67 of the patients had moderate or severe disease, but 126 patients presented with active disease, based on the evaluation of the fecal calprotectin. In patients with ulcerative colitis, only 21 patients had moderate disease, but 76 patients presented with active disease, based on the evaluation of the fecal calprotectin. A large majority of patients had positive CMV IgG. Overall, 10 patients had positive CMV IgM, and 9 patients had a positive qualitative detection of CMV DNA by PCR in the feces. All 400 patients returned negative results after the quantitative detection of CMV DNA in blood by real-time PCR. Analyzing the 19 patients with active infections, we only found that such an association occurred with the use of combined therapy (anti-TNF-alpha + azathioprine)Conclusion
The findings show that latent cytomegalovirus infections are frequent and active cytomegalovirus infection is rare. We did not find any association between an active infection of CMV and inflammatory bowel disease activity. 相似文献86.
87.
Juliana Perez Di Giorgio Gabriela Soto Karina Alleva Cintia Jozefkowicz Gabriela Amodeo Jorge Prometeo Muschietti Nicolás Daniel Ayub 《The Journal of membrane biology》2014,247(2):107-125
Aquaporins (AQPs) are a family of channel proteins, which transport water and/or small solutes across cell membranes. AQPs are present in Bacteria, Eukarya, and Archaea. The classical AQP evolution paradigm explains the inconsistent phylogenetic trees by multiple transfer events and emphasizes that the assignment of orthologous AQPs is not possible, making it difficult to integrate functional information. Recently, a novel phylogenetic framework of eukaryotic AQP evolution showed congruence between eukaryotic AQPs and organismal trees identifying 32 orthologous clusters in plants and animals (Soto et al. Gene 503:165–176, 2012). In this article, we discuss in depth the methodological strength, the ability to predict functionality and the AQP community perception about the different paradigms of AQP evolution. Moreover, we show an updated review of AQPs transport functions in association with phylogenetic analyses. Finally, we discuss the possible effect of AQP data integration in the understanding of water and solute transport in eukaryotic cells. 相似文献
88.
Cintia D. Medina Luciano J. Avila Jack W. Sites Jr Mariana Morando 《Biological journal of the Linnean Society. Linnean Society of London》2014,113(1):256-269
This study presents a detailed phylogeographical analysis of one of the most conspicuous groups of lizards in northwestern Patagonia, the Liolaemus kriegi complex. This region is geographically very complex as a result of Andean orogeny and subsequent volcanism coupled with a long history of glaciations and climatic changes. For 247 individuals we sequenced one mitochondrial gene (cytochrome b) and for a subset we sequenced another mitochondrial gene [12S ribosomal RNA (12S)] and two nuclear fragments [kinesin family member 24 (KIF24) and BA3 ribosomal RNA (BA3)]. We obtained gene trees and mitochondrial and nuclear haploytpe networks, and estimated genetic distances between the main lineages and basic molecular diversity indices. We also performed spatial analysis of molecular variance (SAMOVA) and Bayesian Skyline Plot (BSP) analyses, and concordant patterns from different lines of evidence permitted delimitation of seven lineages: two described species, Liolaemus buergeri and Liolaemus tregenzai; four candidate species, Liolaemus sp. A, Liolaemus sp. B, Liolaemus sp. C, and Liolaemus sp. D; and one lineage that includes all individuals from the geographical range of Liolaemus ceii and L. kriegi, referred to as L. kriegi + L. ceii. We discuss the evolutionary processes that may contribute to the origin of these lineages and their taxonomic and conservation implications. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 256–269. 相似文献
89.
Carla Oliveira-Ribeiro Maria Inês Fernandes Pimentel Liliane de Ftima Antonio Oliveira rica de Camargo Ferreira e Vasconcellos Fatima Conceio-Silva Armando de Oliveira Schubach Aline Fagundes Cintia Xavier de Mello Eliame Mouta-Confort Luciana de Freitas Campos Miranda Claudia Maria Valete-Rosalino Ana Cristina da Costa Martins Raquel de Vasconcellos Carvalhaes de Oliveira Leonardo Pereira Quintella Marcelo Rosandiski Lyra 《PLoS neglected tropical diseases》2021,15(9)
BackgroundTreatment of cutaneous leishmaniasis (CL) remains challenging since the drugs currently used are quite toxic, thus contributing to lethality unrelated to the disease itself but to adverse events (AE). The main objective was to evaluate different treatment regimens with meglumine antimoniate (MA), in a reference center in Rio de Janeiro, Brazil.MethodologyA historical cohort of 592 patients that underwent physical and laboratory examination were enrolled between 2000 and 2017. The outcome measures of effectiveness were epithelialization and complete healing of cutaneous lesions. AE were graded using a standardized scale. Three groups were evaluated: Standard regimen (SR): intramuscular (IM) MA 10–20 mg Sb5+/kg/day during 20 days (n = 46); Alternative regimen (AR): IM MA 5 mg Sb5+/kg/day during 30 days (n = 456); Intralesional route (IL): MA infiltration in the lesion(s) through subcutaneous injections (n = 90). Statistical analysis was performed through Fisher exact and Pearson Chi-square tests, Kruskal-Wallis, Kaplan-Meier and log-rank tests.ResultsSR, AR and IL showed efficacy of 95.3%, 84.3% and 75.9%, with abandonment rate of 6.5%, 2.4% and 3.4%, respectively. IL patients had more comorbidities (58.9%; p = 0.001), were mostly over 50 years of age (55.6%), and had an evolution time longer than 2 months (65.6%; p = 0.02). Time for epithelialization and complete healing were similar in IL and IM MA groups (p = 0.9 and p = 0.5; respectively). Total AE and moderate to severe AE that frequently led to treatment interruption were more common in SR group, while AR and IL showed less toxicity.Conclusions/SignificanceAR and IL showed less toxicity and may be good options especially in CL cases with comorbidities, although SR treatment was more effective. IL treatment was an effective and safe strategy, and it may be used as first therapy option as well as a rescue scheme in patients initially treated with other drugs. 相似文献
90.
Stressmann M Kitao S Griffith M Moresoli C Bravo LA Marangoni AG 《Plant physiology》2004,135(1):364-376
During cold acclimation, winter rye (Secale cereale) plants accumulate pathogenesis-related proteins that are also antifreeze proteins (AFPs) because they adsorb onto ice and inhibit its growth. Although they promote winter survival in planta, these dual-function AFPs proteins lose activity when stored at subzero temperatures in vitro, so we examined their stability in solutions containing CaCl2, MgCl2, or NaCl. Antifreeze activity was unaffected by salts before freezing, but decreased after freezing and thawing in CaCl2 and was recovered by adding a chelator. Ca2+ enhanced chitinase activity 3- to 5-fold in unfrozen samples, although hydrolytic activity also decreased after freezing and thawing in CaCl2. Native PAGE, circular dichroism, and Trp fluorescence experiments showed that the AFPs partially unfold after freezing and thawing, but they fold more compactly or aggregate in CaCl2. Ruthenium red, which binds to Ca(2+)-binding sites, readily stained AFPs in the absence of Ca2+, but less stain was visible after freezing and thawing AFPs in CaCl2. We conclude that the structure of AFPs changes during freezing and thawing, creating new Ca(2+)-binding sites. Once Ca2+ binds to those sites, antifreeze activity, chitinase activity and ruthenium red binding are all inhibited. Because free Ca2+ concentrations are typically low in the apoplast, antifreeze activity is probably stable to freezing and thawing in planta. Ca2+ may regulate chitinase activity if concentrations are increased locally by release from pectin or interaction with Ca(2+)-binding proteins. Furthermore, antifreeze activity can be easily maintained in vitro by including a chelator during frozen storage. 相似文献