The Use of “Use Value”: Quantifying Importance in Ethnobotany

Economic Botany - The Use of “Use Value”: Quantifying Importance in Ethnobotany. Use value (UV) is an index widely used to quantify the relative importance of useful plants. It combines...     

Creatine–facilitated protection of stress caused by disrupted circadian rhythm

Disturbances in natural Circadian rhythm are well-known stress factors, affecting a range of metabolic pathways in the living body including the brain. Hence, discovery of natural compounds that could help to prevent and cure of adverse changes is very important. One of the recently discussed substances is creatine, that is believed to have anti-stressor properties. Recent paper describes the impact of intraperitoneally injected creatine (140 mg/kg) into rats with a disturbed natural circadian rhythm for an extended period of time (30 days). Markedly, creatine-treated animals show positive changes in open-field behavioral parameters, and an increase in certain antioxidant enzymes’ (SOD, catalase) activity in the hippocampus, whereas the concentration of nitric oxide, H₂O₂, and Ca²⁺ are approximated to the control value. Similar findings were also observed in case of Na⁺/K⁺- and Ca²⁺-ATPases. To sum up, the recent findings allow the conclusion that oxidative stress induced by long-term disturbances in natural circadian rhythm is accompanied and likely provoked by an increase in Ca²⁺-cytotoxicity, which is supposedly normalized by the creatine’s indirect action on the NMDA receptor. Therefore, impact on energy mediating pathways has a positive effect on stabilization of antioxidant and various metabolic systems and protecting hippocampal cells from stress.     

High KIR diversity in Amerindians is maintained using few gene-content haplotypes

Interaction between killer cell immunoglobulin-like receptors (KIR) and cognate HLA class I ligands influences the innate and adaptive immune response to infection. The KIR family varies in gene content and allelic polymorphism, thereby, distinguishing individuals and populations. KIR gene content was determined for 230 individuals from three Amerindian tribes from Venezuela: the Yucpa, Bari and Warao. Gene-content haplotypes could be assigned to 212 individuals (92%) because only five different haplotypes were present—group A and four group B. Six different haplotype combinations accounted for >80% of individuals. Each tribe has distinctive genotype frequencies. Despite few haplotypes, all 14 KIR genes are at high frequency in the three tribes, with the exception of 2DS3. Each population has an even frequency of group A and B haplotypes. Allele-level analysis of 3DL1/S1 distinguished five group A haplotypes and six group B haplotypes. The high frequency and divergence of the KIR haplotypes in the Amerindian tribes provide greater KIR diversity than is present in many larger populations. An extreme case being the Yucpa, for whom two gene-content haplotypes account for >90% of the population. These comprise the group A haplotype and a group B haplotype containing all the KIR genes, except 2DS3, that typify the group B haplotypes. Here is clear evidence for balancing selection on the KIR system and the biological importance of both A and B haplotypes for the survival of human populations.Electronic Supplementary Material Supplementary material is available for this article at     

Metal-induced point defects in DNA: model and mechanisms

The aim of this work was to study the role of H3O+ and transition-metal (TM) ions in keto-enol and amino-imino tautomeric transitions in DNA base pairs and depurination. In this regard, we discuss the thermodynamic model of ion-DNA interactions and UV display of double-proton transfer (DPT) in GC. The probabilities and energies of rare tautomeric forms of GC pairs in DNA induced by H3O+ and TMwere determined being in the range from0.02 (forMg2+) to 1 ( forCu2+), and from 0 kcal/m (for Cu2+) to 2.3 kcal/m (for Mg2+), respectively. It was shown that 3'ACC5'/5'TGG3' site of DNA double helix, which corresponds to the only triplet 5'UGG3' of RNA that codes the most valuable amino acid tryptophan, is a good target for TM ions to attack. It was also shown that the only way to obtain the tryptophan-coding 5'UGG3' triplet in RNA via transition-type G --> A point mutation caused by TM ions is their interaction with the site of a DNA double helix, which corresponds to 5'CGG3' triplet of RNA that codes arginine.     

Entamoeba histolytica: the serine-rich gene polymorphism-based genetic variability of clinical isolates from Georgia

It is generally accepted that a majority of individuals infected by Entamoeba histolytica do not develop symptomatic disease. However, the parasite and the host factors contributing to the development of the disease, remain undetermined. It is also unclear why certain individuals develop extra-intestinal amebiasis without exhibiting apparent intestinal symptoms. An outbreak of amebic liver abscess in Tbilisi, Georgia in 1998-1999 suggested that the causative E. histolytica strain had an unusual propensity for extra-intestinal spread. To correlate the genetic differences with pathogenic potential of the parasite, we have examined the SREHP gene polymorphisms among Georgian E. histolytica isolates. Comparison of polymorphic patterns revealed the presence of several different genotypes of E. histolytica, thus preventing an association of a single genotype with hepatic disease, but supporting the previous finding of extensive genetic diversity among E. histolytica isolates from the same geographic origin.     

Protective effect of the KIR2DS1 gene in atopic dermatitis

Atopic dermatitis (AD) is a common skin disease of complex etiology including affected humoral and cellular immune responses. The role of NK cells in development of this disease has been recently postulated, but is still poorly documented. The current study was undertaken to determine the impact of genes for the most polymorphic NK cell receptors, known as killer cell immunoglobulin-like receptors (KIRs), on the development of AD.     

UV damage of collagen: insights from model collagen peptides

Fibrils of Type I collagen in the skin are exposed to ultraviolet (UV) light and there have been claims that collagen photo-degradation leads to wrinkles and may contribute to skin cancers. To understand the effects of UV radiation on collagen, Type I collagen solutions were exposed to the UV-C wavelength of 254 nm for defined lengths of time at 4°C. Circular dichroism (CD) experiments show that irradiation of collagen leads to high loss of triple helical content with a new lower thermal stability peak and SDS-gel electrophoresis indicates breakdown of collagen chains. To better define the effects of UV radiation on the collagen triple-helix, the studies were extended to peptides which model the collagen sequence and conformation. CD studies showed irradiation for days led to lower magnitudes of the triple-helix maximum at 225 nm and lower thermal stabilities for two peptides containing multiple Gly-Pro-Hyp triplets. In contrast, the highest radiation exposure led to little change in the T(m) values of (Gly-Pro-Pro)(10) and (Ala-Hyp-Gly)(10) , although (Gly-Pro-Pro)(10) did show a significant decrease in triple helix intensity. Mass spectroscopy indicated preferential cleavage sites within the peptides, and identification of some of the most susceptible sites of cleavage. The effect of radiation on these well defined peptides gives insight into the sequence and conformational specificity of photo-degradation of collagen.     

Action of a novel pyrrolo[1,2-c][1.3]benzodiazepine on the viability of Jurkat and neuronal/glial cells

We have designed and synthesized several structural isomers of anthramycin (heterocycles 2, 3, 5, 6, and 8) and found that, in particular, pyrrolobenzodiazepine 8 induces DNA cleavage and formation of small fragments of DNA. The cytotoxic effects of 8 were manifested with both non-transformed primary neuronal/glial cells and transformed Jurkat cells. The other compounds did not change the viability either of transformed or of non-transformed cells, and induced DNA cleavage to a lesser extent.     

Normalization of Epigenetic Change in the Genome by Peptide Bioregulator (Ala–Glu–Asp–Gly) in Pulmonary Tuberculosis

International Journal of Peptide Research and Therapeutics - The aim of this study was to evaluate genetic and epigenetic variation of the genome in patients with sensitive pulmonary tuberculosis...