Evolutionary history of Calosomina ground beetles (Coleoptera, Carabidae, Carabinae) of the world as deduced from sequence comparisons of the mitochondrial ND 5 gene

We deduced the phylogenetic relationships of 54 individuals representing 27 species of the Calosomina (Coleoptera, Carabidae) from various regions of the world from the mitochondrial NADH dehydrogenase subunit 5 (ND5) gene sequences. The results suggest that these Calosomina radiated into 17 lineages within a short time about 30 million years ago (Mya). Most of the lineages are composed of a single genus containing only one or a few species. In some cases, several species classified into the same genus (e.g., Calosoma maximowiczi, Calos. inquisitor and Calos. frigidum) appear separately in independent lineages, while in others a series of species classified into different genera fall into one lineage (e.g., Chrysostigma calidum, Blaptosoma chihuahua, Microcallisthenes wilkesi and Callisthenes spp.). Based on this molecular phylogeny and morphological data, the probable evolutionary history and mode of morphological differentiation of the Calosomina are discussed.     

An alternative to radiation hybrid mapping for large-scale genome analysis in barley

The presence of a monosomic gametocidal chromosome (GC) in a barley chromosome addition line of common wheat generates structural aberrations in the barley chromosome as well as in the wheat chromosomes of gametes lacking the GC. A collection of structurally aberrant barley chromosomes is analogous to a panel of radiation hybrid (RH) mapping and is valuable for high-throughput physical mapping. We developed 90 common wheat lines (GC lines) containing aberrant barley 7H chromosomes induced by a gametocidal chromosome, 2C. DNAs isolated from these GC lines provided a panel of 7H chromosomal fragments in a wheat genetic background, comparable with RH mapping panels in mammals. We used this 7H GC panel and the methodology for RH mapping to physically map PCR-based barley markers, SSRs and AFLPs, onto chromosome 7H, relying on polymorphism between the 7H chromosome and the wheat genome. We call this method GC mapping. This study describes a novel adaptation and combination of methods of inducing chromosomal rearrangements to produce physical maps of markers. The advantages of the presented method are similar to RH mapping in that non-polymorphic markers can be used and the mapping panels can be relatively easily obtained. In addition, mapping results are cumulative when using the same mapping set with new markers. The GC lines will be available from the National Bioresources Project-KOMUGI (). Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.     

Validation of Radiation Dose Received by Frozen Unprocessed and Processed Bone during Terminal Sterilisation

Fresh frozen femoral heads (FH) and frozen processed bone (FP) are widely used as a source of allograft bone. The FP bone and some of the FH are terminally sterilised by the National Blood Service Tissue Services (NSBTS), via application of a minimum 25 kGy gamma radiation dose. To comply with the Guidelines for the Blood Transfusion Services in the United Kingdom (2002), frozen musculoskeletal tissue must be maintained below −40 °C during storage and transit. In practice, NBSTS stores bone long-term in −80 °C freezers. During transport for irradiation, a temperature of circa −79 °C is maintained by packing the bone in dry ice. An evaluation of the radiation dose received by bone has previously been made via dosimeters located within the tissue and dry ice, however, some evidence suggests that low temperature can influence the accuracy of the dosimeter readings. The aim of this study was to determine the actual radiation dose received by FH and FP bone during the irradiation process. This was accomplished by comparing radiation dose readings from dosimeters placed in dry ice with dosimeters placed in a dry ice substitute of similar dimensions and density i.e., polytetrafluoroethylene (PTFE) at ambient temperature. New packing formats were developed for both FH and FP bone such that 15 FH or 3 kg of FP bone could be irradiated in one transport box at any given time in a standardised fashion. The data show that low temperature consistently increased dosimeter readings 10–27%, and that radiation dose always fell within the range of 25–40 kGy (FH = 25.1–35.7 kGy; FP bone = 25.2–32.4 kGy).     

Observations on the behavior of vitreous ice at approximately 82 and approximately 12 K

In an attempt to determine why cooling with liquid helium actually proved disadvantageous in our electron cryotomography experiments, further tests were performed to explore the differences in vitreous ice at approximately 82 and approximately 12 K. Electron diffraction patterns showed clearly that the vitreous ice of interest in biological electron cryomicroscopy (i.e., plunge-frozen, buffered protein solutions) does indeed collapse into a higher density phase when irradiated with as few as 2-3 e-/A2 at approximately 12 K. The high density phase spontaneously expanded back to a state resembling the original, low density phase over a period of hours at approximately 82 K. Movements of gold fiducials and changes in the lengths of tunnels drilled through the ice confirmed these phase changes, and also revealed gross changes in the concavity of the ice layer spanning circular holes in the carbon support. Brief warmup-cooldown cycles from approximately 12 to approximately 82 K and back, as would be required by the flip-flop cryorotation stage, did not induce a global phase change, but did allow certain local strains to relax. Several observations including the rates of tunnel collapse and the production of beam footprints suggested that the high density phase flows more readily in response to irradiation. Finally, the patterns of bubbling were different at the two temperatures. It is concluded that the collapse of vitreous ice at approximately 12 K around macromolecules is too rapid to account alone for the problematic loss of contrast seen, which must instead be due to secondary effects such as changes in the mobility of radiolytic fragments and water.     

Genetic characterization of asymmetric somatic hybrids between Bupleurum scorzonerifolium Willd and Triticum aestivum L.: potential application to the study of the wheat genome

In this paper, we describe how Bupleurum scorzonerifolium/Triticum aestivum asymmetric somatic hybrids can be exploited to study the wheat genome. Protoplasts of B. scorzonerifolium Willd were irradiated with ultraviolet light (UV) and fused with protoplasts of common wheat (T. aestivum L.). All cell clones were similar in appearance to those of B. scorzonerifolium, while the regenerated plantlets were either intermediate or B. scorzonerifolium-like. Genotypic screening using isozymes showed that 39.3% of cell clones formed were hybrid. Some of the hybrid cell clones grew vigorously, and differentiated green leaves, shoots or plantlets. DNA marker analysis of the hybrids demonstrated that wheat DNA was integrated into the nuclear genomes of B. scorzonerifolium and in situ karyotyping cells revealed that a few wheat chromosome fragments had been introgressed into B. scorzonerifolium. The average wheat SSR retention frequency of the RH panel was 20.50%, but was only 6.67% in fusions with a non-irradiated donor. B. scorzonerifolium chromosomes and wheat SSR fragments in most asymmetric hybrid cell lines remained stable over a period of 2.5–3.5 years. We suggest the UV-induced asymmetric somatic hybrids between B. scorzonerifolium Willd and T. aestivum L. have the potential for use in the construction of an RH map of the wheat genome.     

Detailed four-way comparative mapping and gene order analysis of the canine ctvm locus reveals evolutionary chromosome rearrangements

Canine tricuspid valve malformation (CTVM) maps to canine chromosome 9 (CFA9), in a region syntenic with gene-dense human chromosome 17q. To define synteny blocks, we analyzed 148 markers on CFA9 using radiation hybrid mapping and established a four-way comparative map for human, mouse, rat, and dog. We identified a large number of rearrangements, allowing us to reconstruct the evolutionary history of individual synteny blocks and large chromosomal segments. A most parsimonious rearrangement scenario for all four species reveals that human chromosome 17q differs from CFA9 and the syntenic rodent chromosomes through two macroreversals of 9.2 and 23 Mb. Compared to a recovered ancestral gene order, CFA9 has undergone 11 reversals of <3 Mb and 2 reversals of >3 Mb. Interspecies reuse of breakpoints for micro- and macrorearrangements was observed. Gene order and content of the ctvm interval are best extrapolated from murine data, showing that multispecies genome rearrangement scenarios contribute to identifying gene content in canine mapping studies.     

剂量率等因素对聚乙烯辐照交联的影响

本文研究了聚乙烯塑料在＾６０Ｃｏ－γ射线辐照下,剂量率等因素对交联度的影响,实验结果表明：交联度随辐照强度提高而增加,当交联度相同时,不同的材料需不同的辐照剂量,在相同的辐照条件下,当制备样品的方法不同时,交联度也不同。     

雪莲对正常及辐射损伤小鼠巨噬细胞功能的影响

本文研究了５０％雪莲水煎剂对正常及５ＧＹ６０Ｃｏ一次性全身照射ＢＡＬＢ／Ｃ小鼠巨噬细胞功能的影响,结果表明：口服５０％雪莲水煎剂能增强巨噬细胞吞噬鸡血球及分泌肿瘤坏死因子（ＴＮＦ）的能力,与相应对照组比较具有显著性差异,提示中药雪莲具有扶正固本提高机体防御机能及促进辐射损伤修复的作用。为该药的临床应用提供了科学依据。     

射线诱导在体造血细胞凋亡的量时效关系的研究

以4—10Gy射线在体损伤的小鼠为模型,应用DNA电泳和流式细胞术等方法证实细胞凋亡是射线损伤在体骨髓造血细胞的途径之一,发现射线诱导的造血细胞凋亡有明显的量效和时效关系。4、6、8和10Gy照射后,细胞凋亡发生率均表现为升高-降低过程,各剂量诱导的凋亡发生率峰值分别出现在照后12、8、4和4h,6和8Gy诱导的凋亡发生率已达最高水平,约为30％,10Gy诱导的凋亡反而要低。上述结果表明,诱导细胞凋亡是射线损伤骨髓造血细胞的一个重要途径,而且凋亡的发生率受照射剂量和照后时间的影响。因此,深入研究射线诱导的细胞凋亡,将有助于揭示射线损伤造血功能的机理。