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11.
Serological differentiation of acute and chronic schistosomiasis using Schistosoma mansoni recombinant protein RP26 总被引:1,自引:0,他引:1
We obtained a recombinant protein encoded by Schistosoma mansoni gene which was able to differentiate acute from chronic schistosomiasis when applied as antigen in enzyme-linked immunosorbent assay (ELISA). A cDNA clone encoding a 26 kDa recombinant protein (RP26) was selected by screening of an adult worm S. mansoni λZAP expression library with rabbit sera produced against PIII, an adult worm protein fraction already known to possess protective and immunomodulating effects. The clone cDNA presented 99% identity with S. mansoni Sm22.3 gene. We assayed IgG reactivity of sera from 18 patients with acute, 25 patients with chronic S. mansoni infection and 20 uninfected donors with RP26 in ELISA. Our results showed that 89% of sera were positive in acute schistosomiasis group, and only 26% in chronic group, without false-positive reactions in uninfected group. In mice the immune response to RP26 increased up to week 9 after infection and then diminished. We proposed that production of antibodies binding to RP26 stopped at the chronic stage of disease. The testing of sera from eight other parasitic infections with RP26 revealed no positive reactions in majority of sera. However, we observed low positive reaction in sera from 20% of leishmaniasis patients. Our results indicate that a recombinant protein RP26 can be used as immunodiagnostic reagent for detection of acute phase of schistosomiasis mansoni. 相似文献
12.
Ibrahim M Hassan W Meinerz DF Leite Gde O Nogueira CW Rocha JB 《Biological trace element research》2012,147(1-3):309-314
It is widely accepted that oxidative stress plays a central role in alcohol-induced pathogenesis. The protective effect of binaphthyl diselenide (NapSe)2 was investigated in ethanol (Etoh)-induced brain injury. Thirty male adult Wistar rats were divided randomly into five groups of six animals each and treated as follows: (1) The control group received the vehicle (soy bean oil, 1 mL/kg, p.o.). (2) Ethanol group of animals was administered with ethanol (70% v/v, 2 mL/kg, p.o.). (3) (NapSe)2 1 mg/kg, 1 mL/kg plus ethanol 70% (v/v, 2 mL/kg, p.o. (5) (NapSe)2 10 mg/kg, 1 mL/kg) plus ethanol 70% (v/v, 2 mL/kg, p.o). After acute treatment, all rats were sacrificed by decapitation. Evidence for oxidative stress in rat brain was obtained from the observed levels of thiobarbituric acid reactive species, of non-protein thiol (NPSH) groups, and of ascorbic acid, as well as from the activities of catalase (CAT) and of superoxide dismutase (SOD). (NapSe)2 compensated the deficits in the antioxidant defense mechanisms (CAT, SOD, NPSH, and ascorbic acid), and suppressed lipid peroxidation in rat brain resulting from Etoh administration. It was concluded that ethanol exposure causes alterations in the antioxidant defense system and induces oxidative stress in rat brain. (NaPSe)2 at 5 mg/kg restored the antioxidant defenses in rat brain and mitigated the toxic effects of alcohol, suggesting that could be used as a potential therapeutic agent for alcohol-induced oxidative damage in rat brain. 相似文献
13.
Fred Bernardes Filho Jaci Maria Santana Regina Coeli Palma de Almeida Glauber Voltan Natlia Aparecida de Paula Marcel Nani Leite Claudia Maria Lincoln Silva Camila Tormena Lean Basoli Joelma Menezes Moises Batista da Silva John Stewart Spencer Wilson Marques Jr Norma Tiraboschi Foss Marco Andrey Cipriani Frade 《PLoS neglected tropical diseases》2020,14(12)
BackgroundThis study evaluates an active search strategy for leprosy diagnosis based on responses to a Leprosy Suspicion Questionnaire (LSQ), and analyzing the clinical, immunoepidemiological and follow-up aspects for individuals living in a prison population.MethodsA cross-sectional study based on a questionnaire posing 14 questions about leprosy symptoms and signs that was distributed to 1,400 prisoners. This was followed by dermatoneurological examination, anti-PGL-I serology and RLEP-PCR. Those without leprosy were placed in the Non-leprosy Group (NLG, n = 1,216) and those diagnosed with clinical symptoms of leprosy were placed in the Leprosy Group (LG, n = 34).FindingsIn total, 896 LSQ were returned (64%), and 187 (20.9%) of the responses were deemed as positive for signs/symptoms, answering 2.7 questions on average. Clinically, 1,250 (89.3%) of the prisoners were evaluated resulting in the diagnosis of 34 new cases (LG), based on well-accepted clinical signs and symptoms, a new case detection rate of 2.7% within this population, while the NLG were comprised of 1,216 individuals. The confinement time medians were 39 months in the LG while it was 36 months in the NLG (p>0.05). The 31 leprosy cases who responded to the questionnaire (LSQ+) had an average of 1.5 responses. The symptoms “anesthetized skin area” and “pain in nerves” were most commonly mentioned in the LG while “tingling, numbness in the hands/feet”, “sensation of pricks and needles”, “pain in nerves” and “spots on the skin” responses were found in more than 30% of questionnaires in the NLG. Clinically, 88.2% had dysesthetic macular skin lesions and 97.1% presented some peripheral nerve impairment, 71.9% with some degree of disability. All cases were multibacillary, confirming a late diagnosis. Anti-PGL-I results in the LG were higher than in the NLG (p<0.0001), while the RLEP-PCR was positive in 11.8% of the patients.InterpretationOur findings within the penitentiary demonstrated a hidden prevalence of leprosy, although the individuals diagnosed were likely infected while living in their former communities and not as a result of exposure in the prison. The LSQ proved to be an important screening tool to help identify leprosy cases in prisons. 相似文献
14.
15.
Santos Francisco Denis Souza Maubrigades Lucas Reichert Gonçalves Vitória Sequeira Franz Helen Cabaldi Rodrigues Paulo Ricardo Centeno Cunha Rodrigo Casquero Leite Fábio Pereira Leivas 《Probiotics and antimicrobial proteins》2021,13(3):655-663
Probiotics and Antimicrobial Proteins - Bacterial spores of the genus Bacillus are being evaluated as adjuvant molecules capable of improving the immune response to vaccines. In this study, we... 相似文献
16.
Mauro C. X. Pinto Betania B. Cota Michele A. Rodrigues Maria F. Leite Elaine M. de Souza‐Fagundes 《Journal of biochemical and molecular toxicology》2013,27(11):479-485
Hypnophilin (HNP) is a sesquiterpene that is isolated from Lentinus cf. strigosus and has cytotoxic activities. Here, we studied the calcium signaling and cytotoxic effects of HNP in UACC‐62 cells, a human skin melanoma cell line. HNP was able to increase the intracellular calcium concentration in UACC‐62 cells, which was blocked in cells stimulated in Ca2+‐free media. HNP treatment with BAPTA‐AM, an intracellular Ca2+ chelator, caused an increase in calcium signals. HNP showed cytotoxicity against UACC‐62 cells in which it induced DNA fragmentation and morphological alterations, including changes in the nuclear chromatin profile and increased cytoplasmatic vacuolization, but it had no effect on the plasma membrane integrity. These data suggest that cytotoxicity in UACC‐62 cells, after treatment with HNP, is associated with Ca2+ influx. Together, these findings suggest that HNP is a relevant tool for the further investigation of new anticancer approaches. © 2013 Wiley Periodicals, Inc. J BiochemMol Toxicol 27:479‐485, 2013; View this article online at wileyonlinelibrary.com . DOI 10.1002/jbt.21507 相似文献
17.
Leonardo P. Farias Greice Krautz-Peterson Cibele A. Tararam Bogar O. Araujo-Montoya Tatiana R. Fraga Henrique K. Rofatto Floriano P. Silva-Jr Lourdes Isaac Akram A. Da'dara R. Alan Wilson Charles B. Shoemaker Luciana C. C. Leite 《PLoS neglected tropical diseases》2013,7(10)
Background
It is believed that schistosomes evade complement-mediated killing by expressing regulatory proteins on their surface. Recently, six homologues of human CD59, an important inhibitor of the complement system membrane attack complex, were identified in the schistosome genome. Therefore, it is important to investigate whether these molecules could act as CD59-like complement inhibitors in schistosomes as part of an immune evasion strategy.Methodology/Principal Findings
Herein, we describe the molecular characterization of seven putative SmCD59-like genes and attempt to address the putative biological function of two isoforms. Superimposition analysis of the 3D structure of hCD59 and schistosome sequences revealed that they contain the three-fingered protein domain (TFPD). However, the conserved amino acid residues involved in complement recognition in mammals could not be identified. Real-time RT-PCR and Western blot analysis determined that most of these genes are up-regulated in the transition from free-living cercaria to adult worm stage. Immunolocalization experiments and tegument preparations confirm that at least some of the SmCD59-like proteins are surface-localized; however, significant expression was also detected in internal tissues of adult worms. Finally, the involvement of two SmCD59 proteins in complement inhibition was evaluated by three different approaches: (i) a hemolytic assay using recombinant soluble forms expressed in Pichia pastoris and E. coli; (ii) complement-resistance of CHO cells expressing the respective membrane-anchored proteins; and (iii) the complement killing of schistosomula after gene suppression by RNAi. Our data indicated that these proteins are not involved in the regulation of complement activation.Conclusions
Our results suggest that this group of proteins belongs to the TFPD superfamily. Their expression is associated to intra-host stages, present in the tegument surface, and also in intra-parasite tissues. Three distinct approaches using SmCD59 proteins to inhibit complement strongly suggested that these proteins are not complement inhibitors and their function in schistosomes remains to be determined. 相似文献18.
Leiz M. C. Véras Vanessa R. R. Cunha Filipe C. D. A. Lima Maria A. Guimar?es Marianne M. Vieira Yuri D. M. Campelo Vanessa Y. Sakai David F. Lima Paulo S. Carvalho Jr Javier A. Ellena Paulo R. P. Silva Luciene C. Vasconcelos Markus Godejohann Helena M. Petrilli Vera R. L. Constantino Yvonne P. Mascarenhas José Roberto de Souza de Almeida Leite 《PloS one》2013,8(6)
This paper presents an industrial scale process for extraction, purification, and isolation of epiisopiloturine (EPI) (2(3H)-Furanone,dihydro-3-(hydroxyphenylmethyl)-4-[(1-methyl-1H-imidazol-4-yl)methyl]-, [3S-[3a(R*),4b]]), which is an alkaloid from jaborandi leaves (Pilocarpus microphyllus Stapf). Additionally for the first time a set of structural and spectroscopic techniques were used to characterize this alkaloid. EPI has shown schistomicidal activity against adults and young forms, as well as the reduction of the egg laying adult worms and low toxicity to mammalian cells (in vitro). At first, the extraction of EPI was done with toluene and methylene chloride to obtain a solution that was alkalinized with ammonium carbonate. The remaining solution was treated in sequence by acidification, filtration and alkalinization. These industrial procedures are necessary in order to remove impurities and subsequent application of the high performance liquid chromatography (HPLC). The HPLC was employed also to remove other alkaloids, to obtain EPI purity higher than 98%. The viability of the method was confirmed through HPLC and electrospray mass spectrometry, that yielded a pseudo molecular ion of m/z equal to 287.1 Da. EPI structure was characterized by single crystal X-ray diffraction (XRD), 1H and 13C nuclear magnetic resonance (NMR) in deuterated methanol/chloroform solution, vibrational spectroscopy and mass coupled thermal analyses. EPI molecule presents a parallel alignment of the benzene and the methyl imidazol ring separated by an interplanar spacing of 3.758 Å indicating a π-π bond interaction. The imidazole alkaloid melts at 225°C and decomposes above 230°C under air. EPI structure was used in theoretical Density Functional Theory calculations, considering the single crystal XRD data in order to simulate the NMR, infrared and Raman spectra of the molecule, and performs the signals attribution. 相似文献
19.
Gehring Christoph Zelarayán Marcelo Correa Luz Ronildson Lima Almeida Rosângela Borges Boddey Robert Michael Leite Márcio Fernandes Alves 《Plant and Soil》2020,454(1-2):447-460
Plant and Soil - Aggressive ruderal plant species pose an increasing problem in anthropically degraded lands. They both affect and are affected by other vegetation and by soil fertility in their... 相似文献
20.
Jovana Karoline Lima Neiva Leite Luciane Viater Turek Ricardo Lehtonen Rodrigues Souza Luciana da Silva Timossi Ana Claudia Vecchi Osiecki Raul Osiecki Lupe Furtado-Alle 《Gene》2013
Polymorphisms of butyrylcholinesterase (BChE) have been reported to be associated to weight, BMI variance and hypertriglyceridemia in adults and adolescents. The aim of the present study was to investigate the association of −116A (SNP: G/A; rs1126680) and 1914G (SNP: A/G; rs3495) variants of BCHE gene with anthropometric and biochemical variables associated with obesity in population sample of 115 individuals, from Southern Brazil. Participants were grouped in two categories: obese (BMI ≥ 30) and non-obese (BMI < 30). The 1914G allele showed significantly higher frequency in the obese group, and carriers of 1914G allele showed lower mean BChE activity when compared to 1914A carriers (p = 0.006). Higher means of BMI (p = 0.02) and triglyceride (TG; p = 0.01) were found in 1914G carriers (BMI = 27.57kg/m2; TG = 150.8 mg/dL) when compared to 1914A homozygotes (BMI = 25.55 kg/m2; TG = 107.9 mg/dL). Carriers of the −116A allele showed lower mean BChE activity than usual homozygotes, and the −116A variant was found in cis with 1914G (p < 0.0001; D′ = 1). The region of BCHE gene that contains the 1914G mutation site is target of microRNAs (miRs) and the response of BChE to glucocorticoids is especially influenced by these miRs. Therefore, it is possible that the 1914G allele can be interfering in gluconeogenesis, hyperglycemia, lipolysis and body fat distribution. This lower activity may cause an imbalance in lipid metabolism, which may lead to an increased predisposition to obesity and to a lower ability to maintain metabolic homeostasis. 相似文献