A new role for PGRP-S (Tag7) in immune defense: lymphocyte migration is induced by a chemoattractant complex of Tag7 with Mts1

PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4⁺ and CD8⁺ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.     

Transgene transmission in chickens by sperm-mediated gene transfer after seminal plasma removal and exogenous DNA treated with dimethylsulfoxide or N,N-dimethylacetamide

Transgenic animals have been successfully produced by mass gene transfer techniques such as sperm-mediated gene transfer (SMGT). The aim of this work was to demonstrate transgene transmission by SMGT in chickens using dimethylsulfoxide (DMSO) or N,N-dimethylacetamide (DMAc) as transfectants after seminal plasma removal to prevent DNase activity. Sperm samples were prepared by repetitive washes, and after each wash sperm motility, seminal plasma proteins, exogenous DNA integrity and its uptake by spermatozoa were evaluated. Laying hens were inseminated using spermatozoa transfected with pEGFP-N1 vector in the presence of DMSO or DMAc. Transgene transmission in newborn chicks was evaluated by in vivo enhanced green fluorescent protein (EGFP) expression, RT-PCR and PCR analysis. DNA internalization was limited to sperm samples washed twice. The presence of DMSO or DMAc during transfection had no effect on fertilization or hatching rates. PCR analysis detected the presence of EGFP DNA in 38% of newborn chicks from the DMSO group and 19% from the DMAc group. EGFP mRNA was detected in 21% of newborn chicks from the DMSO group, as against 8.5% from the DMAc group. However, in vivo expression of EGFP was only observed in a single animal from the DMSO group. Our data revealed that the plasmid DNA-DMSO combination coupled with sperm washes can be an efficient method for transfection in chickens.     

Acridinium ester conjugated to lectin as chemiluminescent histochemistry marker

Abstract

Cell differentiation/dedifferentiation includes changes in oligosaccharide composition and distribution in the cell surface glycoconjugates. Lectins have been used as auxiliary tools in histopathological diagnosis of mammary, uterus and brain pathologies. Acridinium ester (AE) conjugated to biomolecules has been employed in chemiluminescent analytical applications. This work aimed to use a lectin, concanavalin A (Con A), conjugated to AE as a chemiluminescent histochemistry tool. Biopsies of normal and infiltrating duct carcinoma (IDC) of mammary tissues were treated by a Con A–AE derivative. Photon emission, observed during the breakage of the chemical bound between Con A and AE, was quantified, expressed in relative light units (RLU) and correlated to the labelling of the normal and transformed tissues. The results demonstrated that RLU presented a linear relationship with the labelled tissue area in the range 0.125–1.0?cm² (r=0.98). Furthermore, RLU was much higher for the IDC (1283.920×10³±220.621×10³) than the normal tissue (2.565×10³±0.247×10³), namely, about 500 times higher. The Con A–AE conjugation efficiency, differential staining of normal and IDC tissues, and quantification of results contribute to a decrease in the subjectivity in routine histopathological diagnoses and indicate that acrydinum ester can join other lectin marker to be used in histochemistry.     

Virulence and pathogenicity of Candida albicans is enhanced in biofilms containing oral bacteria

This study examined the influence of bacteria on the virulence and pathogenicity of candidal biofilms. Mature biofilms (Candida albicans-only, bacteria-only, C. albicans with bacteria) were generated on acrylic and either analysed directly, or used to infect a reconstituted human oral epithelium (RHOE). Analyses included Candida hyphae enumeration and assessment of Candida virulence gene expression. Lactate dehydrogenase (LDH) activity and Candida tissue invasion following biofilm infection of the RHOE were also measured. Candida hyphae were more prevalent (p < 0.05) in acrylic biofilms also containing bacteria, with genes encoding secreted aspartyl-proteinases (SAP4/SAP6) and hyphal-wall protein (HWP1) up-regulated (p < 0.05). Candida adhesin genes (ALS3/EPA1), SAP6 and HWP1 were up-regulated in mixed-species biofilm infections of RHOE. Multi-species infections exhibited higher hyphal proportions (p < 0.05), up-regulation of IL-18, higher LDH activity and tissue invasion. As the presence of bacteria in acrylic biofilms promoted Candida virulence, consideration should be given to the bacterial component when managing denture biofilm associated candidoses.     

Computational identification and comparative analysis of miRNA precursors in three palm species

Planta - In the present study, miRNA precursors in the genomes of three palm species were identified. Analyzes of sequence conservation and biological function of their putative targets contribute...     

Formicidal activity of indole derivatives on Atta opaciceps (Borgmeier): Lethal,behavioural and locomotive effects

The leaf‐cutting ants of the genus Atta are of extreme importance for agriculture and forestry. Few active products can be employed to control these pests and, therefore, the discovery of new insecticidal products represents a fundamental strategy for its management. In this study, we evaluated the mortality, behaviour and locomotion of workers of Atta opaciceps (Borgmeier) exposed to synthesized indole derivatives. The most active compound was 4d [1‐(1H‐indol‐3‐yl)pentan‐1‐one] (LD₅₀ = 0.018 μg/mg), while the 4e [1‐(1H‐indol‐3‐yl)hexan‐1‐one] (LD₅₀ = 3.82 μg/mg) was the least active compound. These two derivatives reduced the survival of A. opaciceps over time and altered the behaviour and locomotion of these ants. This study demonstrates the potential of indole derivatives to produce new formicidal products, since, in addition to being effective, it also affects the ant's behaviour and locomotion.     

Larvicidal activity of essential oils from Brazilian plants against Aedes aegypti L

Aedes aegypti L. is the major vector of dengue fever, an endemic disease in Brazil. In an effort to find effective and affordable ways to control this mosquito, the larvicidal activities of essential oils from nine plants widely found in the Northeast of Brazil were analyzed by measurement of their LC50. The essential oils were extracted by steam distillation and their chemical composition determined by GL-chromatography coupled to mass spectroscopy. The essential oils from Cymbopogon citratus and Lippia sidoides, reported in the literature to have larvicidal properties against A. aegypti, were used for activity comparison. The results show that Ocimum americanum and Ocimum gratissimum have LC50 of 67 ppm and 60 ppm respectively, compared to 63 ppm for L. sidoides and 69 ppm for C. citratus. These results suggest a potential utilization of the essential oil of these two Ocimum species for the control of A. aegypti.     

Gene Unscrambler for detangling scrambled genes in ciliates

Scrambled genes are surprisingly common in some species of ciliates. Until now there was no software available to analyze automatically these genes. We present here a program that can automatically align the macronuclear and micronuclear forms of a gene, outputting the location of the macronuclear destined segments and pointer sequences. AVAILABILITY: A web version of the program is available free of charge and can be accessed at http://oxytricha.princeton.edu/GeneUnscrambler.htm