In vitro organogenesis and plant regeneration of Thymus serpyllum L.: an important aromatic medicinal plant

An efficient in vitro propagation system has been developed for the rapid micropropagation of Thymus serpyllum L. (Banajwain), an aromatic medicinal herb from nodal explant on MS medium. Phenolic leaching and high rate of contamination was the most significant problem in establishing in vitro culture of Thymus serpyllum which was overcome by preparing explants in an antioxidant ascorbic acid (1000 ppm) at 6°C for 45 min and addition of the same antioxidant (50 mgl⁻¹) to the MS medium. The frequency of shoot production was influenced by different cytokinins (Kn, BAP, and Kn + BAP) and 95.56% shoot induction was observed when MS medium was supplemented with 1.0 + 2.0 mgl⁻¹ (Kn + BAP). The maximum average number of shoots 16.93 ± 2.15 and average length (3.98 ± 0.55) was recorded when MS medium have 0.5 + 2.0 mgl⁻¹ (Kn + BAP). The in vitro regenerated microshoots were rooted on MS and half strength MS medium and there was significant difference in root induction on both media under the influence of auxins (IAA, IBA, and NAA). The maximum average number (11.67 ± 3.03) and average root length (3.88 ± 0.71) was reported in half MS medium having 1.0 mgl⁻¹ IBA. The complete regenerated plantlets were acclimatized under growth chamber before transferring to the earthen pots and showed 90% survival.

Graphical abstract

     

Hierarchical role of fetuin-A and acidic serum proteins in the formation and stabilization of calcium phosphate particles

The serum protein fetuin-A is a potent systemic inhibitor of soft tissue calcification. Fetuin-A is highly effective in the formation and stabilization of protein-mineral colloids, referred to as calciprotein particles (CPPs). These particles ripen in vitro in a two-step process, indicated by a morphological conversion from spheres to larger prolate ellipsoids. Using a combined light scattering and electron microscopic imaging approach we determined that the second-stage particles resulted from a highly anisotropic outgrowth of the first-stage particles. Electron microscopy of ascites fluid from a patient with calcifying peritonitis revealed particles reminiscent of secondary CPPs. Thus, CPPs form in the body and undergo the two-step ripening at least in pathological conditions. Unlike in vitro generated CPPs, ascites-derived CPPs contained little fetuin-A but large amounts of albumin. This prompted us to study the role of fetuin-A combined with other serum proteins in CPP formation. Fetuin-A was indispensable for primary CPP formation. Albumin and acidic proteins in general greatly enhanced the fetuin-A triggered formation of secondary CPPs and, thus, substituted substantial amounts of fetuin-A without loss of inhibition of calcium phosphate precipitation. Thus, direct mineral deposition from solute in the body is unlikely even at low fetuin-A serum levels as long as sufficient bulk acidic protein is available. Collectively fetuin-A and other acidic bulk plasma proteins may be considered as mineral chaperones mediating the stabilization, safe transport, and clearance in the body of calcium and phosphate as colloidal complexes, thus, preventing ectopic calcification.     

The plant macro-remains from the Iceman site (Tisenjoch, Italian–Austrian border, eastern Alps): new results on the glacier mummy’s environment

Archaeobotanical studies are currently being carried out on all the plant remains retrieved from the high alpine site where the Iceman “Ötzi” was found (3,210 m a.s.l.). Preliminary results already show a great diversity of species (121 taxa) mainly originating from lower regions, which must have been transported to the Tisenjoch site by a number of vectors. Spatial modelling has been carried out for one part of the plant remains unequivocally assignable to the Iceman. The resulting patterns indicate that post-depositional displacement processes have affected the material, and even the mummified body itself. It is demonstrated that the influence of cross-contamination resulting from the recovery attempts preceding the excavations can be ruled out by thorough selection of sampled areas and layers. The archaeobotanical results, together with current data from other research fields, strongly suggest that the Iceman had died in an area about 5 m south-west of the position where he was discovered in 1991.     

Breeding system, colony and population structure in the weaver ant Oecophylla smaragdina

Weaver ants ( Oecophylla smaragdina ) are dominant ants in open forests from India, Australia, China and Southeast Asia, whose leaf nests are held together with larval silk. The species, together with its sole congener O. longinoda , has been important in research on biological control, communication, territoriality and colony integration. Over most of the range, only one queen has been found per colony, but the occurrence of several queens per nest has been reported for the Australian Northern Territory. The number of males mating with each queen is little known. Here we report on the colony structure of O. smaragdina using published and new microsatellite markers. Worker genotype arrays reflect the occurrence of habitual polygyny (more than one queen per colony) in 18 colonies from Darwin, Northern Australia, with up to five queens inferred per colony. Monogyny (one queen per colony) with occasional polygyny was inferred for 14 colonies from Queensland, Australia, and 20 colonies from Java, Indonesia. Direct genotyping of the sperm carried by 77 Queensland queens and worker genotypic arrays of established colonies yielded similar results, indicating that less than half of the queens mate only once and some mate up to five times. Worker genotype arrays indicated that queens from Java and the Northern Territory also often mate with more than one male, but less often than those from Queensland. A strong isolation-by-distance effect was found for Queensland samples. The variation uncovered means that O. smaragdina is a more versatile study system than previously supposed.     

Quantitative Trait Loci for Metabolic Syndrome in the Hypertension Genetic Epidemiology Network Study

As part of the Hypertension Genetic Epidemiology Network study, genome scans were performed in two ethnicities on the categorical metabolic syndrome (MetS). Genome scans were performed also on the factor scores produced by factor analysis (quantitative MetS). Heritabilities were highest for the obesity‐insulin (INS) factor and lowest for blood pressure (BP) and central obesity. Seventeen unique putative quantitative trait loci (QTLs) yielded logarithm of the odds ratio (LOD) scores in excess of 1.7, 8 for blacks and 9 for whites. Important QTL findings in whites included an LOD score of 3.19 on chromosome 15q15 for the BP factor, 3.08 on chromosome 8p23 for the lipids‐INS factor, and 3.07 on chromosome 3p26 for the obesity‐INS factor. In blacks, after excluding type 2 diabetics, important QTLs were identified, including an LOD score of 2.77 on 13p12 for the obesity‐INS factor and 2.63 on chromosome 11q24 for the lipids‐INS factor. Categorical MetS had lower results than quantitative MetS. Notably, several loci identified overlap with those identified in other studies for a single or group of traits. The most promising candidate loci on 11q24 for lipids‐INS and 13p12 for obesity‐INS in blacks, 8p23 for lipids‐INS, 14q24 for obesity‐INS, and 15q15 for BP in whites warrant further investigation.     

In vivo evaluation of the uptake of [(123)I]FIAU, [(123)I]IVFRU and [(123)I]IVFAU by normal mouse brain: potential for noninvasive assessment of HSV-1 thymidine kinase gene expression in gliomas

Radioiodinated 5-iodo-1-(2-fluoro-2-deoxy-beta-D-arabinofuranosyl)uracil (F *IAU) is most commonly used for noninvasive assessment of herpes simplex virus type 1 thymidine kinase (HSV-1-tk) gene expression. However, it does not permeate the intact blood-brain barrier (BBB) because of its moderate lipophilicity. In this work, three iodo-nucleosides, FIAU, IVFRU, and IVFAU, were radiolabeled with iodine-123 and tested for permeation of the BBB in mice and for potential measurement of HSV-1-tk gene expression in gliomas. The results demonstrate that brain uptake and retention of these nucleosides is not directly related to their lipophilicity. The low brain uptake of IVFAU, in conjunction with its higher and constant brain/blood ratio, may reflect greater stability against hydrolysis of the N-glycosidic bond. In vivo PET evaluations of [(124)I]IVFRU and [(124)I]IVFAU in tumor-bearing mice are warranted.     

A genome-wide screen reveals evidence for a locus on chromosome 11 influencing variation in LDL cholesterol in the NHLBI Family Heart Study

A genome scan was performed for low-density lipoprotein cholesterol concentration (LDL-C) in white subjects who were ascertained through the NHLBI Family Heart Study (FHS). The NIH Mammalian Genotyping Service (Marshfield, Wis.) genotyped 401 autosomal markers spaced at approximate 10-cM intervals. Additional FHS families were genotyped by the FHS Molecular Laboratory at the University of Utah for 243 markers; 645 subjects were typed in both laboratories so that a combined map of the 644 markers from the two screening sets (average distance of 5.46 cM) could be produced. Analyses were done on 2,799 genotyped subjects in 500 families where at least two genotyped persons in the family had measured LDL-C levels (average number of genotyped family members=5.95). The variance components method was used as implemented in GeneHunter (Kruglyak et al. 1996). Prior to analysis, each phenotype was adjusted, within sex, for age, age squared, body mass index, waist-hip ratio, alcohol, smoking, medication status for diabetes and hypertension, estrogen use, and field center location. Linkage analyses were performed, first excluding 305 subjects on lipid-lowering medications, then again including the data from these subjects. The highest peak was on chromosome 11 at 56.3-56.4 cM, with a maximum lod score of 3.72. Two genome scans of lipid traits in other populations have found peaks in this region. Other scores at or above 1.9 occurred on chromosomes 5 (lod=1.89 at 1.6 cM), 10 (lod=2.47 at 127.1 cM), 17 (lod=2.33 at 116.3 cM), and 21 (lod=2.74 at 45.2 cM).     

Cell cycle-related bystander responses are not increased with LET after heavy-ion irradiation

Evidence has accumulated that irradiated cells affect their unirradiated neighbors, so that they in turn display cellular responses typically associated with direct radiation exposure. These responses are generally known as bystander effects. In this study, cell cycle-related bystander responses were investigated in three strains of human fibroblasts after exposure to densely ionizing radiation. Varying the linear energy transfer (LET) from 11 to 15,000 keV microm(-1) allowed a study of the impact of the complexity of DNA damage in the inducing cells on the responses of bystander cells. Using both broad-beam and microbeam irradiation, transient bystander responses were obtained for the induction of CDKN1A (p21). The latter was also observed when the transmission of bystander signals was limited to soluble factors. Targeted irradiation of single cells in confluent cell monolayers revealed no correlation between the amount of CDKN1A protein in the bystander cells and the radial distance to the targeted cells. In line with the induction of CDKN1A in bystander cells after irradiation with different LETs, a transient delay in the first G1 phase after irradiation of G0/G1 cells was observed. However, the CDKN1A induction revealed no significant effect on premature terminal differentiation considered to underlie fibrosis in irradiated tissue. Thus the unchanged differentiation pattern in bystander cells does not indicate pronounced, long-lasting effects.