Defensins: Natural component of human innate immunity

The widespread use of antibiotics has contributed to a huge increase in the number of resistant bacteria. New classes of drugs are therefore being developed of which defensins are a potential source. Defensins are a group of antimicrobial peptides found in different living organisms, involved in the first line of defense in their innate immune response against pathogens. This review summarizes the results of studies of this family of human antimicrobial peptides (AMPs). There is a special emphasis on describing the entire group and individual peptides, history of their discovery, their functions and expression sites. The results of the recent studies on the use of the biologically active peptides in human medicine are also presented. The pharmaceutical potential of human defensins cannot be ignored, especially considering their strong antimicrobial activity and properties such as low molecular weight, reduced immunogenicity, broad activity spectrum and resistance to proteolysis, but there are still many challenges and questions regarding the possibilities of their practical application.     

Event-related potential evidence for a dual-locus model of global/local processing

We investigated the perceptual time course of global/local processing using event-related potentials (ERPs). Participants discriminated the global or local level of hierarchical letters of different sizes and densities. Participants were faster to discriminate the local level of large/sparse letters and the global level of small/dense letters. This was mirrored in early ERP components: The N1/N2 had smaller peak amplitudes when participants made discriminations at the level that took precedence. Only global discriminations for large/sparse letters led to amplitude enhancement of the later P3 component, suggesting that additional attention-demanding processes are involved in discriminating the global level of these stimuli. Our findings suggest a dual-locus time course for global/local processing: (a) Level precedence occurs early in visual processing; (b) extra processing is required at a later stage, but only for global discriminations of large, sparse, stimuli, which may require additional attentional resources for active grouping.     

Intestinal mucosa permeability following oral insulin delivery using core shell corona nanolipoparticles

Chitosan nanoparticles (NC) have excellent capacity for protein entrapment, favorable epithelial permeability, and are regarded as promising nanocarriers for oral protein delivery. Herein, we designed and evaluated a class of core shell corona nanolipoparticles (CSC) to further improve the absorption through enhanced intestinal mucus penetration. CSC contains chitosan nanoparticles as a core component and pluronic F127-lipid vesicles as a shell with hydrophilic chain and polyethylene oxide PEO as a corona. These particles were developed by hydration of a dry pluronic F127-lipid film with NC suspensions followed by extrusion. Insulin nested inside CSC was well protected from enzymatic degradation. Compared with NC, CSC exhibited significantly higher efficiency of mucosal penetration and, consequently, higher cellular internalization of insulin in mucus secreting E12 cells. The cellular level of insulin after CSC treatment was 36-fold higher compared to treatment with free insulin, and 10-fold higher compared to NC. CSC significantly facilitated the permeation of insulin across the ileum epithelia, as demonstrated in an ex vivo study and an in vivo absorption study. CSC pharmacological studies in diabetic rats showed that the hypoglycemic effects of orally administrated CSC were 2.5-fold higher compared to NC. In conclusion, CSC is a promising oral protein delivery system to enhance the stability, intestinal mucosal permeability, and oral absorption of insulin.     

Notch Regulates the Generation of Diverse Cell Types From the Lateral Lineage of Drosophila Antennal Lobe

Abstract:

Diverse neuronal cell types arise from the lateral neuroblast in the antennal lobe of Drosophila. The authors show that loss of Notch function from the entire lineage during development leads to an absence of local interneurons (LNs) with a concomitant increase in the number of projection neurons (PNs). The presence of the intracellular domain of Notch was observed within the nucleus of newly born neurons within the neuroblast lineage. This leads to the suggestion that Notch acts in a binary fate decision to determine formation of LNs and PNs, resulting in two distinct hemilineages from the single neuroblast. The observation of nuclear Notch in several neuroblast lineages leads us to speculate that this mechanism is widespread during the developing Drosophila brain.     

ANTI-ALLERGIC EFFECTS OF SANGUISORBA OFFICINALIS ON ANIMAL MODELS OF ALLERGIC REACTIONS

ABSTRACT

We investigated the effect of aqueous extract of Sanguisorba officinalis L.(Rosaceae) root (SOAE) on the immediate-type allergic reactions in vivo and in vitro. SOAE (0.01 to 1 g/kg) inhibited systemic allergic reaction induced by compound 48/80. When SOAE was employed in a systemic allergic reaction test, the plasma histamine levels were reduced in a dose-dependent manner. SOAE (0.001 to 1 g/kg) dose-dependently inhibited passive cutaneous anaphylaxis (PCA) activated by anti-dinitrophenyl (DNP) IgE. SOAE (0.001 to 1 mg/mL) also dose-dependently inhibited the histamine release from rat peritoneal mast cells (RPMC) activated by compound 48/80 or anti-DNP IgE. The level of cyclic AMP (cAMP) in RPMC, When SOAE was added, significantly increased compared with that of normal control. Moreover, SOAE (0.01 to 1 mg/mL) had a significant inhibitory effect on anti-DNP IgE-induced tumor necrosis factor-α (TNF-α) production. These results suggest that SOAE may be beneficial in the regulation of immediate-type allergic reaction.     

Multi-level basis selection of wavelet packet decomposition tree for heart sound classification

Wavelet packet transform decomposes a signal into a set of orthonormal bases (nodes) and provides opportunities to select an appropriate set of these bases for feature extraction. In this paper, multi-level basis selection (MLBS) is proposed to preserve the most informative bases of a wavelet packet decomposition tree through removing less informative bases by applying three exclusion criteria: frequency range, noise frequency, and energy threshold. MLBS achieved an accuracy of 97.56% for classifying normal heart sound, aortic stenosis, mitral regurgitation, and aortic regurgitation. MLBS is a promising basis selection to be suggested for signals with a small range of frequencies.