Polymorphic microsatellite loci isolated from Cervus unicolor (Cervidae) show inbreeding in a domesticated population of Taiwan Sambar deer.

Primers for eight microsatellites were developed; they successfully amplified DNA from 20 domesticated Formosan Sambar deer (Cervus unicolor swinhoei). All loci were polymorphic, with 10-19 alleles per locus. The average observed heterozygosity across loci and samples was 0.310, ranging from 0 to 0.750 at each locus. All loci but one, CU18, deviated from Hardy-Weinberg equilibrium due to excessive homozygosity in these domesticated broodstocks, reflecting inbreeding. These microsatellite loci will be useful, not only for assessment of population structure and genetic variability, but also for conservation of wild deer populations in Taiwan.

Characterization of O(6)-methylguanine-DNA-methyltransferase (O(6)-MGMT) activity in Xiphophorus fishes.

We utilized a custom-synthesized double-strand oligonucleotide containing a single O(6)-methylguanine (O(6)-MG) residue within a restriction endonuclease recognition site to determine O(6)-methylguanine-DNA-methyltransferase (O(6)-MGMT) activity in various tissue extracts prepared from Xiphophorus fish. The results suggest Xiphophorus fish O(6)-MGMT activity has many of the same characteristics as Escherichia coli and mammalian O(6)-MGMT's including rapid reaction kinetics consistent with stoichiometric removal of methyl groups, but exhibits a temperature optimum of 23 degrees C. Results from protein extract activity assays indicate O(6)-MGMT activity patterns among four Xiphophorus tissues followed the order: brain> or =testes>gill> or =liver. In mammals, O(6)-MGMT activity is high in liver, while activity in brain is minimal (i.e. approximately 9% of liver); however, we report that in the Xiphophorus fishes examined, brain tissue extracts exhibited much higher (approximately six-fold) O(6)-MGMT activity levels than liver. Comparison of O(6)-MGMT activity between Xiphophorus species employed in tumor induction experiments did not indicate significant differences in ability to clear the pre-mutagenic O(6)-MG from the oligonucleotide substrate.

Relative base excision repair in Xiphophorus fish tissue extracts.

To begin characterizing DNA repair capability among Xiphophorus species, we adapted oligonucleotide-based DNA repair assays to extracts of fish tissues. Here, we report the initial results of relative base excision repair (BER) capability among 3 inbred Xiphophorus fish lines representing 2 species (X. maculatus and X. couchianus), and interspecies hybrid F(1) animals produced by crossing them. Overall, data from uracil- N-glycosylase (UNG)-initiated BER assay (UNG-BER) indicate that brain tissue extracts generally possess higher BER activity than do gill and liver extracts. UNG-BER activities in gill and liver extracts were similar. The BER activity in the tissues of F(1) interspecies hybrids followed the activity pattern of the X. couchianus parent in gill and liver extracts, was similar to the X. maculatus parent in brain extracts, but exhibited a reduced repair capacity in gill tissue extracts compared with either parent. We discuss the use of oligonucleotide-based DNA repair assays to elucidate the role that inheritance of DNA repair potential may play in susceptibility to disease and tumorigenesis in the intact organism.

Identification of an accurate soil suspension/dispersion modeling method for use in estimating health-based soil cleanup levels of hexavalent chromium in chromite ore processing residues.

The primary health concern associated with chromite ore processing residues (COPR) at sites in Hudson County, NJ, is the inhalation of Cr(VI) suspended from surface soils. Since health-based soil standards for Cr(VI) will be derived using the inhalation pathway, soil suspension modeling will be necessary to estimate site-specific, health-based soil cleanup levels (HBSCLs). The purpose of this study was to identify the most appropriate particulate emission and air dispersion models for estimating soil suspension at these sites based on their theoretical underpinnings, scientific acceptability, and past performance. The identified modeling approach, the AP-42 particulate emission model and the fugitive dust model (FDM), was used to calculate concentrations of airborne Cr(VI) and TSP at two COPR sites. These estimated concentrations were then compared to concentrations measured at each site. The TSP concentrations calculated using the AP-42/FDM soil suspension modeling approach were all within a factor of 3 of the measured concentrations. The majority of the estimated air concentrations were greater than the measured, indicating that the AP-42/FDM approach tends to overestimate on-site concentrations. The site-specific Cr(VI) HBSCLs for these two sites calculated using this conservative soil suspension modeling approach ranged from 190 to 420 mg/kg.

Tracheal tear during laryngopharyngectomy and transhiatal oesophagectomy: a case report.

A case is reported of a tracheal tear developing during laryngopharyngectomy and transhiatal oesophagectomy. Ventilation and oxygenation were managed by removing the tracheostomy tube and advancing a straight cuffed armoured tube via the tracheostomy into one main stem bronchus and applying CPAP to the other bronchus via a Foley catheter. Following gastrointestinal reconstruction, the membranous tracheal tear was repaired via a right lateral thoracotomy.

Transient growth requirement in Bacillus subtilis following the cessation of exponential growth.

During an investigation of the parameters controlling mutations in Bacillus subtilis we observed that this bacterium exhibits a transient growth requirement for two nonessential amino acids (glutamic acid and isoleucine) during a type of postexponential growth on a minimal medium.

Rapid reversal of life-threatening diltiazem-induced tetany with calcium chloride.

We describe a patient who developed tetany with sudden respiratory arrest after the infusion of intravenous diltiazem. The administration of calcium chloride rapidly resolved the patient's tetany with prompt recovery of respiratory function, averting the need for more aggressive airway management and ventilatory support. The emergency physician should be aware that life-threatening tetany may accompany the administration of intravenous diltiazem and that calcium chloride may be a rapid and effective remedy.

The phylogenetic positions of the conifer genera Amentotaxus Phyllocladus, and Nageia inferred from 18S rRNA sequences.

To determine the evolutionary positions of the conifer genera Amentotaxus, Phyllocladus, and Nageia, we obtained 18S rRNA sequences from 11 new taxa representing the major living orders and families of gymnosperms. With the published Chlamydomonas as an outgroup, phylogenetic analyses of our new data and available sequences indicate that (1) the Gnetales form a monophyletic group, which is an outgroup to the conifers, (2) the conifers are monophyletic, (3) Taxaceae, Cephalotaxaceae, Cupressaceae, and Taxodiaceae form a monophyletic group, (4) Amentotaxus is closer to Torreya than to Cephalotaxus, suggesting that Amentotaxus is better to be classified as a member of Taxaceae, (5) Phyllocladus, Dacrycarpus, Podocarpus, and Nageia form a monophyletic group, and (6) Pinaceae is an out-group to the other families of conifers. Our finding that Phyllocladus is a sister group of the Podocarpaceae disagrees with the suggestion that the phylloclade of the genus is an ancient structure and that the genus is a terminal taxon within the Podocarpaceae. The genus Nageia is more closely related to Podocarpus than to Dacrycarpus and was derived from within the Podocarpaceae. In conclusion, our data indicate that in conifers, the uniovulate cone occurred independently in Taxacaeae and Cephalotaxaceae, and in Podocarpaceae after the three families separated from Pinaceae, and support the hypothesis that the uniovulate cone is derived from reduction of a multiovulate cone.

Molecular phylogeny of extant gymnosperms and seed plant evolution: analysis of nuclear 18S rRNA sequences.

To study the evolutionary relationships among the four living gymnosperm orders and the interfamilial relationships in each order, a set of 65 nuclear 18S rRNA sequences from ferns, gymnosperms, and angiosperms was analyzed using the neighbor-joining and maximum-parsimony methods. With Selaginella as the outgroup, the analysis strongly indicates that the seed plants form a monophyletic group with the ferns as a sister group. Within the seed plants the angiosperms are clearly a monophyletic group. Although the bootstrap support for the monophyly of the gymnosperm clade is moderate, the monophyly is further supported by its lack of angiosperm-specific indels. Within the gymnosperms there appear to be three monophyletic clades: Cycadales-Ginkgoales, Gnetales, and Coniferales. The cycad-ginkgo clade is the earliest gymnosperm lineage. Given the strong support for the sister group relationship between Gnetales and Coniferales, it is unlikely that Gnetales is a sister group of the angiosperms, contrary to the view of many plant taxonomists. Within Coniferales, Pinaceae is monophyletic and basal to the remaining conifer families, among which there are three monophyletic clades: Phyllocladaceae-Podocarpaceae, Araucariaceae, and Sciadopityaceae-Taxaceae-Cephalotaxaceae-Taxodiacea e-Cupressaceae. Within the latter clade, Sciadopityaceae may be an outgroup to the other four families. Among the angiosperms, no significant cluster at the level of subclass was found, but there was evidence that Nymphaeaceae branched off first. Within the remaining angiosperms, the monocots included in this study are nested and form a monophyletic group. This study attests to the utility of nuclear 18S rRNA sequences in addressing relationships among living gymnosperms. Considerable variation in substitution rates was observed among the ferns and seed plants.

Comparison of two fibrin glues in anastomoses and skin closure.

To control intra-operative haemorrhage, fibrin glues are preferred by many surgeons because of their biological advantages and convenience of application. Manufacturers have developed a few kinds of fibrin glues with a little difference in their composition. This study was to compare the effectiveness of two commercially available fibrin glues; Greenplast (Green Cross P. D. Company, Yongin, Korea) and Tisseel (Baxter-Immuno AG, Vienna, Austria). They were applied experimentally to several kinds of surgery in dogs - renal vessel anastomosis, partial splenectomy, intestinal anastomosis and incision skin wound - and evaluated for their haemostatic and adhesive effects. When the two glues were applied in renal vessel anastomosis, the amount of haemorrhage in artery and vein decreased significantly. They also decreased the haemorrhage in partial splenectomy. At 10 min after application of the glues to an incision skin wound, the tensile strengths developed were significantly higher than that of control. The present study indicates that two-component fibrin glues have a haemostatic effect as a mechanical barrier in renal vessel anastomosis and an adhesive effect in the early stage of incision skin wound closure, and the two glues have similar effects with no complications.