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91.
Isabella Mary A. Reis Eric Umehara Rodrigo S. Conceição Larissa de M. Oliveira Manoelito Coelho dos S. Junior Thais A. Costa-Silva Maiara Amaral Andre G. Tempone Alexsandro Branco João Henrique G. Lago 《化学与生物多样性》2021,18(9):e2100362
In the present study, five known γ-lactones (majoranolide B – 1 , majorenolide – 2 , majorynolide – 3 , lincomolide D – 4 , and isolinderanolide E – 5 ), as well as a new one (perseanolide – 6 ), were isolated from Persea fulva and P. americana. All isolated compounds exhibited potential activity against trypomastigote forms of Trypanosoma cruzi, whereas compounds 2 (EC50 of 4.8 μM) and 6 (EC50 of 3.6 μM) displayed superior activity than the positive control benznidazole (EC50 of 16.4 μM), with selectivity index (SI) values of 17.8 and >55.6, respectively (benznidazole, SI>12.2). Molecular docking studies were performed for 1 – 6 against six T. cruzi molecular targets. Using this approach, we observed that, even though perseanolide ( 6 ) showed favorable docking to several studied targets, the results were especially promising for hypoxanthine phosphoribosyl transferase (PDB 1TC1). As PDB 1TC1 is associated to the transference of a monophosphorylated ribose from phosphoribosylpyrophosphate (PRPP) in the ribonucleotide synthesis pathway, this interaction may affect the survival of T. cruzi in mammalian cells. The data herein also indicate that possible intermolecular interactions between 6 and PDB 1TC1 derive from (i) hydrogen bonds in the α,β-unsaturated-γ-lactone unity and (ii) hydrophobic interactions in the long-chain alkyl group. Based on our results, perseanolide ( 6 ), reported for the first time in this work, can auspiciously contribute to future works regarding new trypanocidal agents. 相似文献
92.
Ricardo Kusuda Flaviane Cadetti Maria I Ravanelli Thais A Sousa Sônia Zanon Fernando L De Lucca Guilherme Lucas 《Molecular pain》2011,7(1):17
Background
MicroRNAs (miRNAs) are short non-coding RNAs that inhibit translation of target genes by binding to their mRNAs. The expression of numerous brain-specific miRNAs with a high degree of temporal and spatial specificity suggests that miRNAs play an important role in gene regulation in health and disease. Here we investigate the time course gene expression profile of miR-1, -16, and -206 in mouse dorsal root ganglion (DRG), and spinal cord dorsal horn under inflammatory and neuropathic pain conditions as well as following acute noxious stimulation.Results
Quantitative real-time polymerase chain reaction analyses showed that the mature form of miR-1, -16 and -206, is expressed in DRG and the dorsal horn of the spinal cord. Moreover, CFA-induced inflammation significantly reduced miRs-1 and -16 expression in DRG whereas miR-206 was downregulated in a time dependent manner. Conversely, in the spinal dorsal horn all three miRNAs monitored were upregulated. After sciatic nerve partial ligation, miR-1 and -206 were downregulated in DRG with no change in the spinal dorsal horn. On the other hand, axotomy increases the relative expression of miR-1, -16, and 206 in a time-dependent fashion while in the dorsal horn there was a significant downregulation of miR-1. Acute noxious stimulation with capsaicin also increased the expression of miR-1 and -16 in DRG cells but, on the other hand, in the spinal dorsal horn only a high dose of capsaicin was able to downregulate miR-206 expression.Conclusions
Our results indicate that miRNAs may participate in the regulatory mechanisms of genes associated with the pathophysiology of chronic pain as well as the nociceptive processing following acute noxious stimulation. We found substantial evidence that miRNAs are differentially regulated in DRG and the dorsal horn of the spinal cord under different pain states. Therefore, miRNA expression in the nociceptive system shows not only temporal and spatial specificity but is also stimulus-dependent.93.
Thais Regina Garlet Eduardo Benedetti Parisotto Guilherme da Silva de Medeiros Letícia Cristina Radin Pereira Emilia Ad dison Machado Moreira Eduardo Monguilhott Dalmarco Juliana Bastos Dalmarco Danilo Wilhelm Filho 《Life sciences》2013
Aims
The aim of this study was to evaluate the antioxidant status and oxidative stress biomarkers in the blood of children and teenagers with Down syndrome.Main methods
The analysis of enzymatic antioxidant defenses, such as the activities of catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione transferase (GST), non-enzymatic antioxidants, such as levels of reduced glutathione (GSH), uric acid (UA) and vitamin E, as well as oxidative damage indicators, such as protein carbonyls (PC) levels and lipoperoxidation (TBARS), of DS individuals (n = 20) compared to healthy controls (n = 18). Except the vitamin E was measured by HPLC, all other markers were measured spectrophotometrically.Key Findings
Antioxidant enzymes analysis showed significant increases in the SOD (47.2%), CAT (24.7%) and GR (49.6%) activities in DS subjects. No significant difference in GPx activity was detected while GST activity (61.2%) was decreased, and both responses may be consequence of the depletion of GSH (24.9%) levels. There were no significant differences in TBARS levels, while PC levels showed decreased (31.7%) levels compared to healthy controls, which may be related to the increase (16.1%) found in serum UA. Levels of vitamin E showed no significant differences between DS individuals compared to controls.Significance
The results revealed a systemic pro-oxidant status in DS individuals, evidenced by the increased activity of some important antioxidant enzymes, together with decreased GSH levels in whole blood and elevated UA levels in plasma, probably as an antioxidant compensation related to the redox imbalance in DS individuals. 相似文献94.
Eduardo Fernandes Camacho ícaro Boszczowski Maristela Pinheiro Freire Fernando Campos Gomes Pinto Thais Guimaraes Manuel Jacobsen Teixeira Silvia Figueiredo Costa 《PloS one》2013,8(2)
Background
Studies on the implantation of care routines showed reduction on EVD catheter-related infections rates; however zero tolerance is difficult to be achieved. The objective of this study was to assess the impact of an educational intervention on the maximal reduction on rates of EVD-related infections.Methodology/Principal Findings
The quasi-experimental (before-after intervention) study occurred in two phases: pre-intervention, from April 2007 to July 2008, and intervention, from August 2008 to July 2010. Patients were followed for 30 days after the removal of the EVD, and EVD-related infections were considered as only those with laboratorial confirmation in the CSF. Observations were made of the care of the EVD and compliance with Hygiene of the Hands (HH), a routine of care was drawn up, training was given, and intervention was made to reduce the time the EVD catheter remained in place.Results
during the study, 178 patients were submitted to 194 procedures, corresponding to 1217 EVD catheters-day. Gram-negative agents were identified in 71.4% of the infections during the pre-intervention period and in 60% during the intervention period. During the study, EVD-related infection rates were reduced from 9.5% to 4.8% per patient, from 8.8% to 4.4% per procedure, and the incidence density dropped from 14.0 to 6.9 infections per 1000 catheters-day (p = 0.027). The mortality reduced 12% (from 42% to 30%).Conclusions/Significance
During one year after the fourth intervention, no microbiologically identified infection was documented. In light of these results, educational intervention proved to be a useful tool in reducing these rates and showed also impact on mortality. 相似文献95.
Melissa?de?Freitas Cordeiro-Silva Andressa?Barbosa Marília?Santiago Mariana?Provetti Raquel?Spinassé?Dettogni Thais?Trist?o?Tovar Eliete?Rabbi-Bortolini Iúri?Drumond?LouroEmail author 《Molecular biology reports》2011,38(2):1309-1313
In developed countries deafness has a genetic cause in over 60% of the cases. Contrastingly, in Brazil, it is estimated that
only 16% of all deafnesses are caused by genetic factors. Among hereditary hearing deficiencies, approximately half is caused
by mutations in the Gap Junction Protein Beta-2 (GJB2) gene, which encodes the protein Connexin 26 (Cx26). There are four mutations in this gene that present high prevalence in
specific ethnical groups, namely, 35delG, 167delT, 235delC, and W24X. The 35delG mutation is the most frequent one, occurring in homozygosity or in compound heterozygosity with mutations in the GJB2 and GJB6 genes. This study aims to determine the prevalence of GJB2-35delG, GJB2-167delT, GJB2-235delC, GJB2-W24X, del (GJB6-D13S1830), and del (GJB6-D13S1854) mutations in patients with nonsyndromic deafness in the Espirito Santo State, Brazil. A total of 77 individuals were evaluated,
from which 88.3% presented normal genotypes for all analyzed mutations, 1.3% were compound heterozygotes for 35delG-GJB2/D13S1830-GJB6, 1.3% were compound heterozygotes for 35delG/D13S1854-GJB6, 3.9% were homozygotes for the 35delG mutation and 5.2% were heterozygotes for 35delG/GJB2. The frequency of mutant alleles 35delG/GJB2,
del (D13S1830/GJB6), and del (D13S1854/GJB6) was 7.8, 0.65, and 0.65%, respectively. Mutations 167delT, 235delC, and W24X were not detected. Determining the prevalence of specific mutations related to inherited deafness in a population can contribute
to the development of more efficient and affordable molecular diagnostic protocols, and help in the genetic counseling of
patients and their families. 相似文献
96.
Lopes MS Sales Júnior PA Lopes AG Yoshida MI Silva TH Romanha AJ Alves RJ Oliveira RB 《Memórias do Instituto Oswaldo Cruz》2011,106(8):1055-1057
In this study we prepared an inclusion complex between an iodide analogue of metronidazole (MTZ-I) and cyclodextrin (CD) to develop a safer and more effective method of treating Trypanosoma cruzi infections. According to our results, MTZ-I and MTZ-I:β-CD were 10 times more active than MTZ, demonstrating that the presence of an iodine atom on the side chain increased the trypanocidal activity while maintaining its cytotoxicity. The selective index shows that MTZ-I was 10 times more active against T. cruzi than it was against mammalian cells. The modification of MTZ side chains provides a promising avenue for the development of new drugs. 相似文献
97.
Hokeness-Antonelli KL Crane MJ Dragoi AM Chu WM Salazar-Mather TP 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(9):6176-6183
Chemokine responses critical for inflammation and promotion of effective innate control of murine CMV (MCMV) in liver have been shown to be dependent on immunoregulatory functions elicited by IFN-alphabeta. However, it remains to be determined whether upstream factors that promote viral sensing resulting in the rapid secretion of IFN-alphabeta in liver differ from those described in other tissues. Because plasmacytoid dendritic cells (pDCs) are known producers of high levels of systemic IFN-alpha in response to MCMV, this study examines the in vivo contribution of pDCs to IFN-alpha production in the liver, and whether production of the cytokine and ensuing inflammatory events are dependent on TLR9, MyD88, or both. We demonstrate that whereas MyD88 deficiency markedly impaired secretion of IFN-alpha, production of the cytokine was largely independent of TLR9 signaling, in the liver. MyD88 and TLR9 were needed for IFN-alpha production in the spleen. Moreover, hepatic but not splenic pDCs produced significant amounts of intracellular IFN-alpha in the absence of TLR9 function during infection. Furthermore, production of CCL2, CCL3, and IFN-gamma, as well as the accumulation of macrophages and NK cells, was not affected in the absence of functional TLR9 in the liver. In contrast, these responses were dramatically reduced in MyD88(-/-) mice. Additionally, MyD88(-/-) but not TLR9(-/-) mice exhibited increased sensitivity to virus infection in liver. Collectively, our results define contrasting compartmental functions for TLR9 and MyD88, and suggest that the infected tissue site uniquely contributes to the process of virus sensing and regulation of localized antiviral responses. 相似文献
98.
dos Santos Amanda Ribeiro Fraga-Silva Thais Fernanda de Fátima Almeida-Donanzam Débora dos Santos Rodolfo Ferreira Finato Angela Carolina Soares Cleverson Teixeira Lara Vanessa Soares Almeida Nara Lígia Martins Andrade Maria Izilda de Arruda Olavo Speranza de Arruda Maria Sueli Parreira Venturini James 《Mycopathologia》2022,187(1):15-30
Mycopathologia - We established three immunocompetent murine models of pulmonary mucormycosis to determine the involvement of the adaptive immune response in host resistance in pulmonary... 相似文献
99.
Tiago M. S. Freitas Ana Thais T. De Paula Híngara Leo Naraiana L. Benone Luciano F. A. Montag 《Zeitschrift fur angewandte Ichthyologie》2019,35(3):793-795
The present study shows the length–weight relationships (LWR) for 11 stream fish species from Anapu River Basin, in eastern Amazon, Pará State, Brazil. Samplings were carried out in October and November 2010, 2012 and 2013, and fishes were collected using hand nets of 55 cm of diameter and 2 mm mesh size. Fixed specimens were measured for standard length (cm) and total weight (g). Allometric coefficients b varied from 2.606 to 3.335 and coefficients of determination (R2) varied from 0.902 to 0.986. Shrinkage effect must be considered in future investigations in order to provide a correction factor. 相似文献
100.
Drought Tolerance Conferred to Sugarcane by Association with Gluconacetobacter diazotrophicus: A Transcriptomic View of Hormone Pathways 总被引:1,自引:0,他引:1