251 research outputs found
Composition and evaluation of the lethality of Lippia gracilis essential oil to adults of Biomphalaria glabrata and larvae of Artemia salina
Lippia gracilis essential oil (LGEO) was evaluated for its molluscicidal activity against Biomphalaria glabrata and toxicity to brine shrimps (Artemia salina). L. gracilis was collected from the city Tomar do Gerú- Sergipe, Brazil. The LGEO were characterized by gas chromatography-mass spectrometry (GC/MS). The values of LC10, LC50 and LC90 were respectively 36.9, 62.2 and 82.8 ppm for B. glabrata and 19.6, 23.6 and 26.1 ppm for A. salina. GC/MS analysis showed a total volatile content of 98.6% in the LGEO. The major components were identified as thymol (24.0%), p-cymene (15.9%), methyl-thymol (11.7%), γ-terpinene (10.9%) and β-caryophyllene (7.8%).Keywords: Chemical composition, Lippia species, molluscicidal activity, Verbenacea
Exposure to Domestic and Community Violence and Subjective Well-Being in Adolescents
Abstract There is major exposure to domestic and community violence during adolescence, which has been negatively related to well-being. This work aimed to identify relationships between domestic and community violence and the levels of subjective well-being perceived by adolescents, considering sex and age. The participants were 426 adolescents from public schools in the south of Brazil; 62% were girls, with a mean age of 14.91 years old ( SD = 1.65), who answered one instrument about exposure to violence and another about well-being. Results indicated greater domestic violence exposure among girls and greater community exposure among boys. The age range from 16 to 18 years old was the most exposed to domestic violence. Boys reported greater well-being and less negative affect. Differences in violence exposure may be related to roles of gender in our society. Well-being promotion is highlighted as a resource for confronting violence among adolescents
Dendritic cell-specific delivery of Flt3L by coronavirus vectors secures induction of therapeutic antitumor immunity
Efficacy of antitumor vaccination depends to a large extent on antigen targeting to dendritic cells (DCs). Here, we assessed antitumor immunity induced by attenuated coronavirus vectors which exclusively target DCs in vivo and express either lymphocyte- or DC-activating cytokines in combination with a GFP-tagged model antigen. Tracking of in vivo transduced DCs revealed that vectors encoding for Fms-like tyrosine kinase 3 ligand (Flt3L) exhibited a higher capacity to induce DC maturation compared to vectors delivering IL-2 or IL-15. Moreover, Flt3L vectors more efficiently induced tumor-specific CD8(+) T cells, expanded the epitope repertoire, and provided both prophylactic and therapeutic tumor immunity. In contrast, IL-2- or IL-15-encoding vectors showed a substantially lower efficacy in CD8(+) T cell priming and failed to protect the host once tumors had been established. Thus, specific in vivo targeting of DCs with coronavirus vectors in conjunction with appropriate conditioning of the microenvironment through Flt3L represents an efficient strategy for the generation of therapeutic antitumor immunity
Partial Netrin-1 Deficiency Aggravates Acute Kidney Injury
The netrin family of secreted proteins provides migrational cues in the developing central nervous system. Recently, netrins have also been shown to regulate diverse processes beyond their functions in the brain, incluing the ochrestration of inflammatory events. Particularly netrin-1 has been implicated in dampening hypoxia-induced inflammation. Here, we hypothesized an anti-inflammatory role of endogenous netrin-1 in acute kidney injury (AKI). As homozygous deletion of netrin-1 is lethal, we studied mice with partial netrin-1 deletion (Ntn-1+/− mice) as a genetic model. In fact, Ntn-1+/− mice showed attenuated Ntn-1 levels at baseline and following ischemic AKI. Functional studies of AKI induced by 30 min of renal ischemia and reperfusion revealed enhanced kidney dysfunction in Ntn-1+/− mice as assessed by measurements of glomerular filtration, urine flow rate, urine electrolytes, serum creatinine and creatinine clearance. Consistent with these findings, histological studies indicated a more severe degree kidney injury. Similarly, elevations of renal and systemic inflammatory markers were enhanced in mice with partial netrin-1 deficiency. Finally, treatment of Ntn-1+/− mice with exogenous netrin-1 restored a normal phenotype during AKI. Taking together, these studies implicate endogenous netrin-1 in attenuating renal inflammation during AKI
Intervening with Urinary Tract Infections Using Anti-Adhesives Based on the Crystal Structure of the FimH–Oligomannose-3 Complex
Escherichia coli strains adhere to the normally sterile human uroepithelium using type 1 pili, that are long, hairy surface organelles exposing a mannose-binding FimH adhesin at the tip. A small percentage of adhered bacteria can successfully invade bladder cells, presumably via pathways mediated by the high-mannosylated uroplakin-Ia and alpha3beta1 integrins found throughout the uroepithelium. Invaded bacteria replicate and mature into dense, biofilm-like inclusions in preparation of fluxing and of infection of neighbouring cells, being the major cause of the troublesome recurrent urinary tract infections.We demonstrate that alpha-D-mannose based inhibitors of FimH not only block bacterial adhesion on uroepithelial cells but also antagonize invasion and biofilm formation. Heptyl alpha-D-mannose prevents binding of type 1-piliated E. coli to the human bladder cell line 5637 and reduces both adhesion and invasion of the UTI89 cystitis isolate instilled in mouse bladder via catheterization. Heptyl alpha-D-mannose also specifically inhibited biofilm formation at micromolar concentrations. The structural basis of the great inhibitory potential of alkyl and aryl alpha-D-mannosides was elucidated in the crystal structure of the FimH receptor-binding domain in complex with oligomannose-3. FimH interacts with Man alpha1,3Man beta1,4GlcNAc beta1,4GlcNAc in an extended binding site. The interactions along the alpha1,3 glycosidic bond and the first beta1,4 linkage to the chitobiose unit are conserved with those of FimH with butyl alpha-D-mannose. The strong stacking of the central mannose with the aromatic ring of Tyr48 is congruent with the high affinity found for synthetic inhibitors in which this mannose is substituted for by an aromatic group.The potential of ligand-based design of antagonists of urinary tract infections is ruled by the structural mimicry of natural epitopes and extends into blocking of bacterial invasion, intracellular growth and capacity to fluxing and of recurrence of the infection
Overexpression of DNA Polymerase Zeta Reduces the Mitochondrial Mutability Caused by Pathological Mutations in DNA Polymerase Gamma in Yeast
In yeast, DNA polymerase zeta (Rev3 and Rev7) and Rev1, involved in the error-prone translesion synthesis during replication of nuclear DNA, localize also in mitochondria. We show that overexpression of Rev3 reduced the mtDNA extended mutability caused by a subclass of pathological mutations in Mip1, the yeast mitochondrial DNA polymerase orthologous to human Pol gamma. This beneficial effect was synergistic with the effect achieved by increasing the dNTPs pools. Since overexpression of Rev3 is detrimental for nuclear DNA mutability, we constructed a mutant Rev3 isoform unable to migrate into the nucleus: its overexpression reduced mtDNA mutability without increasing the nuclear one
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