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101.
The trypomastigote small surface antigen (TSSA) is a mucin-like molecule from Trypanosoma cruzi, the etiological agent of Chagas disease, which displays amino acid polymorphisms in parasite isolates. TSSA expression is restricted to the surface of infective cell-derived trypomastigotes, where it functions as an adhesin and engages surface receptors on the host cell as a prerequisite for parasite internalization. Previous results have established TSSA-CL, the isoform encoded by the CL Brener clone, as an appealing candidate for use in serology-based diagnostics for Chagas disease. Here, we used a combination of peptide- and recombinant protein-based tools to map the antigenic structure of TSSA-CL at maximal resolution. Our results indicate the presence of different partially overlapping B-cell epitopes clustering in the central portion of TSSA-CL, which contains most of the polymorphisms found in parasite isolates. Based on these results, we assessed the serodiagnostic performance of a 21-amino-acid-long peptide that spans TSSA-CL major antigenic determinants, which was similar to the performance of the previously validated glutathione S-transferase (GST)-TSSA-CL fusion molecule. Furthermore, the tools developed for the antigenic characterization of the TSSA antigen were also used to explore other potential diagnostic applications of the anti-TSSA humoral response in Chagasic patients. Overall, our present results provide additional insights into the antigenic structure of TSSA-CL and support this molecule as an excellent target for molecular intervention in Chagas disease.  相似文献   
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Neuroinflammation is common in neurodegenerative diseases including Parkinson disease (PD). Expression of 25 mRNAs was assessed with TaqMan‐PCR including members of the complement system, colony stimulating factors, Toll family, cytokines IL‐8, IL‐6, IL‐6ST, IL‐1B, TNF‐α family, IL‐10, TGFβ family, cathepsins and integrin family, in the substantia nigra pars compacta, putamen, frontal cortex area 8 and angular gyrus area 39, in a total of 43 controls and 56 cases with PD‐related pathology covering stages 1–6 of Braak. Up‐regulation of IL‐6ST was the only change in the substantia nigra at stages 1–2. Down‐regulation of the majority of members examined occurred in the substantia nigra from stage 4 onwards. However, region‐dependent down‐ and up‐regulation of selected mRNAs occurred in the putamen and frontal cortex, whereas only mRNA up‐regulated mRNAs were identified in the angular cortex from stage 3 onwards in PD cases. Protein studies in frontal cortex revealed increased IL6 expression and reduced IL‐10 with ELISA, and increased IL‐6 with western blotting in PD. Immunohistochemistry revealed localization of IL‐5, IL‐6 and IL‐17 receptors in glial cells, mainly microglia; IL‐5, IL‐10 and M‐CSF in neurons; TNF‐α in neurons and microglia; and active NF‐κB in the nucleus of subpopulations of neurons and glial cells in PD. Distinct inflammatory responses, involving pro‐ and anti‐inflammatory cytokines, and variegated mediators of the immune response occur in different brain regions at the same time in particular individuals. Available information shows that altered α‐synuclein solubility and aggregation, Lewy body formation, oxidative damage and neuroinflammation converge in the pathogenesis of PD.  相似文献   
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Objective:To investigate the wound healing properly of Napoleona vogelii leaf extract in folkloric medicine.Methods:Roth sexes of adult albino rats(n=25) were used in this study and another group(n=30) were subjected to acute toxicity test(LD_(50)) of the plant extract.For the LD_(50),three randomized groups of 5 rats were first treated with 10,100,1 000 mg/kg body weight(bw),orally.This w as followed by a second treatment of 1500,3000,and 5 000 mg/kg bw of the leaf extract with continual monitoring of the animals for mortality or non-mortality.Incision wounds(1.3cm) were created on the skin of five groups of 5 rals using surgical blade under anesthesia.The first group was topically treated with petroleum jelly alone,group 2 was topically applied 400 mg/mL w/v of the reference drug,Neobaein,while group 3-5 were topically treated with 5-50 mg/mL w/v of the plant extract,respectively.Results:The percentage yield of the extract was 49.80%w/w dry matter.The phytochemical analysis revealed several bioactive constituents including glycosides,tannins,alkaloids,perpenoids.saponins,steroids,proteins,and carbohydrates.The LD_(50) was beyond our experimental limit and was not determined.Increased concentrations(5,20,and 50mg/mL w/v) of the extract had significant(ANOVA,P0.05) healing effect on the incision wounds giving rise to 125%-140% while treatmentawith Neobacin resulted in 150% healing effect on the third treatment regimen compared to the control(100%).Conclusions:These data indicate that Napoleona vogelii leaf extract contains potent bioactive compounds containing wound healing activity,substantiating its use as a wound healer in folkloric medicine.  相似文献   
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