Different susceptibility of indigenous populations of Lymantria dispar to the exotic entomopathogen Entomophaga maimaiga

The recovery of the host‐specific entomopathogen Entomophaga maimaiga is still limited to certain world areas, although it is recently spreading to Eastern Europe. This study evaluated the effectiveness and fitness of an E. maimaiga isolate from Balkans against Lymantria dispar populations collected along the Italian peninsula and main islands, where the fungus has never been reported. As a result of different bioassays, the pathogenicity against gypsy moth larvae was generally confirmed, although significant differences among insects feeding upon diverse forest plant species were observed. The lack of significant susceptibility of other lepidopteran species from the same areas is also reported.     

Impact of genetic variations in ADORA2A gene on depression and symptoms: a cross-sectional population-based study

Purinergic Signalling - Genetic variants involved in adenosine metabolism and its receptors were associated with increased risk for psychiatric disorders, including anxiety, depression, and...     

Type III-A CRISPR-Cas Csm Complexes: Assembly,Periodic RNA Cleavage,DNase Activity Regulation,and Autoimmunity

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Spacer Acquisition Rates Determine the Immunological Diversity of the Type II CRISPR-Cas Immune Response

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Biogenic synthesis of silver nanoparticles using Brazilian propolis

Biological methods have been used to synthesize silver nanoparticles through materials such as bacteria, fungi, plants, and propolis due to their reducing properties, stabilizer role and environmentally friendly characteristic. Considering the antimicrobial activity of propolis as well as the broad-spectrum antibacterial effects of silver nanoparticles, this study aim to describe the use of Brazilian propolis to synthesize silver nanoparticles (AgNP-P) and investigate its antimicrobial activity. The synthesis was optimized by factorial design, choosing the best conditions for smaller size particles. AgNP-P demonstrated a maximum absorbance at 412 nm in ultraviolet-visible spectra, which indicated a spherical format and its formation. Dynamic light scattering demonstrated a hydrodynamic size of 109 nm and polydispersity index less than 0.3, showing a good size distribution and stability. After its purification via centrifugation, microscopy analysis corroborates the format and showed the presence of propolis around silver nanoparticle. X-ray diffraction peaks were attributed to the main planes of the metallic silver crystalline structure; meanwhile infrared spectroscopy demonstrated the main groups responsible for silver reduction, represented by ∼22% of AgNP-P indicates by thermal analysis. Our product revealed an important antimicrobial activity indicating a synergism between propolis and silver nanoparticles as expected and promising to be an effective antimicrobial product to be used in infections.     

Conformation-sensitive antibodies against alzheimer amyloid-beta by immunization with a thioredoxin-constrained B-cell epitope peptide

Immunotherapy against the amyloid-beta (Abeta) peptide is a valuable potential treatment for Alzheimer disease (AD). An ideal antigen should be soluble and nontoxic, avoid the C-terminally located T-cell epitope of Abeta, and yet be capable of eliciting antibodies that recognize Abeta fibrils and neurotoxic Abeta oligomers but not the physiological monomeric species of Abeta. We have described here the construction and immunological characterization of a recombinant antigen with these features obtained by tandem multimerization of the immunodominant B-cell epitope peptide Abeta1-15 (Abeta15) within the active site loop of bacterial thioredoxin (Trx). Chimeric Trx(Abeta15)n polypeptides bearing one, four, or eight copies of Abeta15 were constructed and injected into mice in combination with alum, an adjuvant approved for human use. All three polypeptides were found to be immunogenic, yet eliciting antibodies with distinct recognition specificities. The anti-Trx(Abeta15)4 antibody, in particular, recognized Abeta42 fibrils and oligomers but not monomers and exhibited the same kind of conformational selectivity against transthyretin, an amyloidogenic protein unrelated in sequence to Abeta. We have also demonstrated that anti-Trx(Abeta15)4, which binds to human AD plaques, markedly reduces Abeta pathology in transgenic AD mice. The data indicate that a conformational epitope shared by oligomers and fibrils can be mimicked by a thioredoxin-constrained Abeta fragment repeat and identify Trx(Abeta15)4 as a promising new tool for AD immunotherapy.     

Induced prion protein controls immune-activated retroviruses in the mouse spleen

The prion protein (PrP) is crucially involved in transmissible spongiform encephalopathies (TSE), but neither its exact role in disease nor its physiological function are known. Here we show for mice, using histological, immunochemical and PCR-based methods, that stimulation of innate resistance was followed by appearance of numerous endogenous retroviruses and ensuing PrP up-regulation in germinal centers of the spleen. Subsequently, the activated retroviruses disappeared in a PrP-dependent manner. Our results reveal the regular involvement of endogenous retroviruses in murine immune responses and provide evidence for an essential function of PrP in the control of the retroviral activity. The interaction between PrP and ubiquitous endogenous retroviruses may allow new interpretations of TSE pathophysiology and explain the evolutionary conservation of PrP.     

Immunohistochemical detection of Langerhans cells in dental granulomas and radicular cysts

Objective Dental granulomas (DGs) and radicular cysts (RCs) are chronic periapical lesions frequently involving the jaws. Langerhans cells (LCs) are dendritic cells responsible for the presentation of antigens to T lymphocytes. This study examined the expression of LCs in DG and RCs by immunohistochemical staining. Study Design Eighteen cases of DGs and 26 cases of RCs were analyzed using anti-CD1a marker. Results CD1a-labeled LCs were observed in 11.1% of DGs and in 69.2% of RCs, showing a significant correlation (P < 0.0001; Fisher’s test). In DGs, LCs were only observed in granulation tissue, showing discrete immunostaining density. In RCs, LCs exhibited both a round and a dendritic shape in all epithelial layers. Although a correlation was observed between immunostaining density and epithelial thickness, as well as between immunostaining and inflammatory intensity, the differences were not significant in radicular cysts. Conclusion Langerhans cells provide important insight into the immunopathogenesis of chronic periapical lesions.