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991.
Amorim IF Silva SM Figueiredo MM Moura EP Castro RS Lima TK Gontijo Nde F Michalick MS Gollob KJ Tafuri WL 《PloS one》2011,6(11):e27679
The aim of the present study was to investigate TLR2 expression in peripheral blood monocytes from dogs naturally infected with Leishmania (Leishmania) infantum to determine whether it correlates with CD11b/CD18 (CR3) expression, and to evaluate the potential of dogs as sources of infection using phlebotomine xenodiagnosis. Forty eight dogs were serologically diagnosed with L. infantum infection by indirect immunofluorescence antibody test (IFAT) and enzyme linked immunosorbent assay (ELISA). Parasitological exams from bone-marrow aspirates were positive by PCR analysis. All dogs were clinical defined as symptomatic. Ear skin tissue samples were obtained for immunohistochemistry (IHQ) analysis. The potential of these dogs as a source of infection using phlebotomine xenodiagnosis (XENO) was evaluated. Flow cytometry was carried out on peripheral blood mononuclear cells using superficial receptors including CD14, CD11b, TLR2 and MHCII. IHQ ear skin tissue parasite load and XENO where done where we found a strict correlation (r = 0.5373). Dogs with higher expression of MFI of CD11b inside CD14 monocytes were represented by dogs without parasite ear tissue load that were unable to infect phlebotomines (IHQ−/XENO−). Dogs with lower expression of MFI of CD11b inside CD14 monocytes were represented by dogs with parasite ear tissue load and able to infect phlebotomines (IHQ+/XENO+) (p = 0,0032). Comparable results were obtained for MFI of MHCII (p = 0.0054). In addition, considering the population frequency of CD11b+TLR2+ and CD11b+MHCII+, higher values were obtained from dogs with IHQ−/XENO− than dogs with IHQ+/XENO+ (p = 0.01; p = 0.0048, respectively). These data, together with the TLR2 and NO assays results (CD11b+TLR2+ and NO with higher values for dogs with IHQ−/XENO− than dogs with IHQ+/XENO+), led to the conclusion that IHQ−/XENO− dogs are more resistant or could modulate the cellular immune response essential for Leishmania tissue clearance. 相似文献
992.
Phospholipase A2 (PLA2) lipolytic activity can be regarded as a limiting factor for the development of inflammatory processes by restricting the production of pro-inflammatory mediators, hence representing a valuable therapeutic target for drugs that are able to modulate the activity of this enzyme. In the current work, the hydrolysis of phospholipids by PLA2 was monitored with acrylodan-labelled intestinal fatty acid binding protein (ADIFAB) and this fluorescence based technique was also used to access the enzymatic inhibitory effect of non-steroidal anti-inflammatory drugs (NSAIDs). The intrinsic fluorescence of PLA2 tryptophan residues was further used to gain complementary information regarding the accessibility of these residues on the PLA2 structure upon interaction with the NSAIDs tested; and to calculate the NSAIDs-PLA2 binding constants. Finally, circular dichroism (CD) measurements were performed to evaluate changes in PLA2 conformation resultant from the inhibitory effect of the drugs tested. Overall, results gathered in this study point to the conclusion that the studied NSAIDs inhibit PLA2 activity due to a disturbance of the enzyme binding efficiency to membrane interface possibly by a shielding effect of the Trp residues required for the membrane interfacial binding step that precedes lipolysis process. 相似文献
993.
Laura A. Da Costa Bibiana García-Bailo Christoph H. Borchers Alaa Badawi Ahmed El-Sohemy 《The Journal of nutritional biochemistry》2013,24(5):842-847
Vitamin C has been associated with a reduced risk of chronic diseases, but the biological pathways regulated by vitamin C are not all known. The objective was to use a proteomics approach to identify plasma proteins associated with circulating levels of ascorbic acid. Men and women (n= 1022) 20–29 years of age from the Toronto Nutrigenomics and Health Study completed a general health and lifestyle questionnaire and a 196-item food frequency questionnaire and provided a fasting blood sample. Circulating ascorbic acid was analyzed by high-performance liquid chromatography, and a mass-spectrometry-based multiple reaction monitoring method was used to measure 54 proteins abundant in plasma that are involved in numerous physiologic pathways. Mean protein concentrations were compared across tertiles of serum ascorbic acid using analysis of covariance adjusted for sex, ethnocultural group, season of blood draw, hormonal contraceptive use among women, waist circumference and tertiles of plasma α-tocopherol. A Bonferroni significance level of P<.0009 was applied, and analyses were adjusted for multiple comparisons using the Tukey–Kramer procedure. Levels of complement C9, ceruloplasmin, alpha-1-anti-trypsin, angiotensinogen, complement C3, vitamin D binding protein and plasminogen were inversely associated with levels of ascorbic acid. The inverse association between ascorbic acid and vitamin D binding protein was highest in those with higher levels of serum 25-hydroxyvitamin D. In conclusion, several plasma proteins from various physiologic pathways are significantly associated with circulating levels of ascorbic acid. These findings suggest that vitamin C may have novel physiological effects. 相似文献
994.
Bizuti Matheus Ribeiro Starck Édina da Silva Fagundes Kimberly Kamila Puhle Josiano Guilherme Lima Lucas Medeiros de Oliveira Natan Rodrigues de Sousa Silva Guilherme Vinicio Silva Débora Tavares Resende e 《Molecular and cellular biochemistry》2022,477(6):1725-1737
Molecular and Cellular Biochemistry - Respiratory infections of viral origin have become the leading cause of infectious diseases in the world. In 2020, the World Health Organization (WHO) declared... 相似文献
995.
Fingerprints of South American monkeys of the genera Alouatta, Ateles and Cebus were studied. Dermatoglyphics were analysed in relation to pattern intensities; the distribution of symmetric and asymmetric designs was also determined. Results have been related to some aspects of the contribution of dermatoglyphics to the study of Primate morphological evolution. 相似文献
996.
Reverse enzyme synthesis in microemulsion-based organo-gels. 总被引:8,自引:0,他引:8
G D Rees M da Graca Nascimento T R Jenta B H Robinson 《Biochimica et biophysica acta》1991,1073(3):493-501
Lipase from three different sources has been immobilised in microemulsion-based gels (MBGs) with retention of catalytic activity. Such lipase-containing MBGs prove to be novel solid-phase catalysts for use in apolar organic solvents such as n-heptane. Using these systems, preparative-scale synthesis of a wide variety of esters under mild conditions was possible with products easily isolated and obtained in high yield. Stereoselective esterification of octan-2-ol was observed for all three lipases with Chromobacterium viscosum (CV) lipase yielding product with an enantiomeric excess of 92%. Repeated usage of a CV lipase-containing MBG resulted in a visually unchanged gel whose activity was 75% of the initial value after 30 days. The sectioned MBGs were well suited for use in column flow reactors and were also found to be effective esterification catalysts at temperatures as low as -20 degrees C. 相似文献
997.
This study presents a list of 34 Anoplura type specimens deposited in the Werneck Collection of Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil. It includes 18 holotypes, 16 allotypes, 88 paratypes and 10 neotypes, distributed among the genera: Enderleinellus, Fahrenholzia, Haematopinus, Hoplopleura, Linognathus, Microthoracius, Pecaroecus, Polyplax and Pterophthirus. The types are related according to their respective data and literature. 相似文献
998.
Terra Wagner da S. Bull Érika S. Morcelli Samila R. Moreira Rafaela R. Maciel Leide Laura F. Almeida João Carlos de A. Kanashiro Milton M. Fernandes Christiane Horn Adolfo 《Biometals》2021,34(3):661-674
BioMetals - The cytotoxicity against five human tumor cell lines (THP-1, U937, Molt-4, Colo-205 and NCI-H460) of three water soluble copper(II) coordination compounds containing the ligands... 相似文献
999.
Leduc Antoine O. H. C. Costa Jessica S. Oliveira do Nascimento Silva Renata R. Winandy Gabrielle S. M. de Araújo Carlos B. 《Journal of Ethology》2021,39(2):225-234
Journal of Ethology - Noise pollution may impair the cognitive performances of several animal species, producing suboptimal behavioral responses. Involuntary shifts in attention from noise... 相似文献
1000.
Killen B. A. Brito da Luz S. Lloyd D. G. Carleton A. D. Zhang J. Besier T. F. Saxby D. J. 《Biomechanics and modeling in mechanobiology》2021,20(2):521-533
Biomechanics and Modeling in Mechanobiology - Computational modelling is an invaluable tool for investigating features of human locomotion and motor control which cannot be measured except through... 相似文献