In vitro biogeneration of pure thiosulfinates and propanethial-S-oxide

A model reaction system was developed for generating pure thiosulfinates and propanethial-S-oxide (PTSO) using an isolated alliinase (EC 4.4.1.4) and isolated or synthetic alk(en)yl-L-cysteine sulfoxides (ACSO). Reaction yields ranged from 30 to 60% after 3 h at 21-23 degrees C, and organosulfur reaction products were extracted into CHCl3 to yield product preparations of controlled composition. A pure thiosulfinate or PTSO was derived from a single ACSO, and a preparation containing a mixture of four thiosulfinate species was derived from reaction mixtures employing binary ACSO substrate systems. Identities of homologous thiosulfinates and PTSO were confirmed by 1H NMR. This approach has the potential to be used as a preparative tool for yielding pure thiosulfinates and PTSO to facilitate the study of chemical and biological properties of this group of compounds or as a means to study the dynamics of organosulfur chemistry in preparations from Allium spp.     

Mesophilic and thermotolerant actinomycetes in strongly heated soils

Mesophilic and thermotolerant actinomycetes were identified in strongly heated desert-steppe soils of Mongolia, mountainous meadow soils of the Central Caucasus, and cyanobacterial films on volcanic ash near hot springs of Kamchatka. Thermotolerant actinomycetes in these soil objects were more abundant and had a greater taxonomic diversity in comparison with mesophilic actinomycetes. Thermotolerant Streptomyces were present in all the objects, except for sample 117 from the desert-steppe soil and the cyanobacterial film on volcanic ash. Thermotolerant actinomycetes from the Micromonospora and Actinomadura genera predominated in the desert-steppe soil; representatives of the Micromonospora genus predominated in the cyanobacterial film on volcanic ash, and representatives of the Microtetraspora genus predominated in the samples of geyserite near hot springs of Kamchatka.     

Identification and Quantification of Pathogenic Pythium spp. from Soils in Eastern Washington Using Real-Time Polymerase Chain Reaction

ABSTRACT Traditional methods of quantifying Pythium spp. rely on the use of selective media and dilution plating. However, high variability is inherent in this type of enumeration and counts may not be representative of the pathogenic population of Pythium spp. Variable regions of the internal transcribed spacer of the rDNA were used to design species-specific primers for detection and quantification of nine Pythium spp. from soils in eastern Washington. Primer pairs were designed for Pythium abappressorium, P. attrantheridium, P. heterothallicum, P. irregulare group I, P. irregulare group IV, P. paroecandrum, P. rostratifingens, P. sylvaticum, and P. ultimum and used with real-time polymerase chain reaction. Standard curves were generated for each of the species using SYBR Green I fluorescent dye for detection of amplification. Seventy-seven isolates of Pythium were screened to confirm specificity of each primer set. DNA was extracted from soil and standard curves were generated for P. irregulare group I, P. irregulare group IV, and P. ultimum to correlate populations of each species in the soil with quantities of DNA amplified from the same soil. Examination of raw field soils revealed results similar to those observed in previous studies. This new technique for the quantification of Pythium spp. is rapid and accurate, and will be a useful tool in the future study of these pathogenic Pythium spp.     

Cryptic genetic diversity in “widespread” Southeast Asian bird species suggests that Philippine avian endemism is gravely underestimated

Mistakenly classifying morphologically cryptic endemic species as populations of widespread species potentially interferes with the conservation of biodiversity because undetected endemics that are imperilled may lack appropriate protection. It also impedes the reconstruction of the evolutionary history of a taxon by obscuring the number and distributional limits of species. Here, we present genetic and phylogenetic evidence corroborated by morphology that Philippine populations of seven widespread, non-migratory passerine birds might represent unrecognized, distinct species. An extrapolation based on this finding suggests that the proportion of endemic bird species in the Philippines could be much higher than currently estimated. This high degree of cryptic diversity in a well-studied, volant taxon implies that large numbers of unrecognized species can be expected in less thoroughly studied groups. We predict that genetic investigations of insular populations of widespread species will frequently reveal unrecognized island endemics, and because of the vulnerability of island habitats and their biota, these taxa may be particularly susceptible to extinction.     

Tick diversity, abundance and seasonal dynamics in a resource-poor urban environment in the Free State Province

The objectives of this study were to determine the diversity, seasonal dynamics and abundance of ticks infesting cattle in urban, small-scale farming communities in and around Botshabelo and Thaba Nchu in the eastern Free State Province, South Africa. A total of ten cattle, ear-tagged for individual identification, were investigated monthly at each of five localities. Adult ticks were removed from the right hand side of each animal and placed in containers filled with 70% ethanol. They were subsequently identified and their numbers quantified. Immature Otobius megnini were counted but not removed. A total of 244,538 adult ticks of ten different species were collected over the 12-month study period. The tick species, in decreasing order of relative abundance, were: Boophilus decoloratus (87.26%), Rhipicephalus evertsi evertsi (6.86%), Hyalomma marginatum rufipes (2.42%), Otobius megnini (1.85%) Rhipicephalus follis (0.76%), Rhipicephalus gertrudae (0.54%), Rhipicephalus sp. (0.21%), Ixodes rubicundus (0.08%), Hyalomma truncatum (0.01%) and Margaropus winthemi (0.004%). The three most abundant species, namely B. decoloratus, R. evertsi evertsi and H. marginatum rufipes, occurred at all localities but with significant differences in abundance. M. winthemi ticks occurred only in the Thaba Nchu area and were not found at any of the there localities in Botshabelo. Significant differences in tick burdens between the six warm months (September to February) and the six cooler months (March to August) were found for most of the species recorded. Boophilus decoloratus occurred in significantly higher numbers in autumn (March to May) and winter (June to August) compared to spring (September to November) and summer (December to February), with 76.8% of the total B. decoloratus burden occurring during the cooler months.     

Femoral capital physeal fractures in dogs: 34 cases (1979-1989)

Complications associated with femoral capital physeal (CP) fractures in 34 dogs were evaluated. Fractures were surgically repaired, using divergent K-wires or lag screws; radiographic follow-up was available for 21 CP fractures. In all cases, radiographic abnormalities such as degenerative joint disease and resorption of the femoral neck and/or head were seen. Changes were more severe when fracture occurred at an early age. For 4 of 21 dogs (20%), femoral head and neck excision was performed because of complications associated with CP fracture repair. Prognosis for femoral CP fractures is guarded, although affected dogs should be able to function as pets.     

Vitamin E supplementation in beef finishing diets containing 35% wet distillers grains with solubles: feedlot performance and carcass characteristics

Supplementation of vitamin E has indications for improving cattle health, performance, and retail characteristics when included in grain-based diets. This experiment was conducted to determine performance and carcass characteristics of steers fed diets containing wet distillers grains with solubles (WDGS) and supplemented with vitamin E. Steers of mixed Bos indicus and Bos taurus breeding (n = 199; BW = 363 ± 32 kg) were blocked by BW and assigned to 1 of 4 supplemental vitamin E (VITE) treatments [0 (control), 125, 250, and 500 IU·steer(-1)·d(-1)], which were fed for the last 97 d of the feeding period. Two blocks were on feed 129 d, and 3 blocks were fed for 150 d. Steers were fed a dry-rolled corn-based finishing diet with 35% WDGS (DM basis). Individual BW were measured initially, the initial day of vitamin E supplementation, and the day of slaughter. Carcass weights were collected at slaughter, and carcass data were collected after a 36-h chill. Body weight and ADG were not affected by VITE (P ≥ 0.34). There was a tendency for a linear (P = 0.08) increase in carcass-adjusted BW with increasing VITE. Use of carcass-adjusted final BW resulted in a linear increase (P = 0.04) in ADG with increasing VITE. Pre-vitamin E and vitamin E feeding period DMI were not affected (P ≥ 0.24) by VITE, but there was a tendency (P = 0.08) for a linear increase in overall DMI with increasing VITE. No difference (P ≥ 0.29) occurred in G:F measures using BW gains, but G:F using carcass-adjusted BW gains resulted in a trend (P = 0.11) for G:F to increase linearly with increasing VITE. Hot carcass weights tended (P = 0.08) to increase linearly with increasing dietary vitamin E. Vitamin E supplementation resulted in no effects (P ≥ 0.13) on measured carcass characteristics. Calculated yield grades (YG) were also not affected (P ≥ 0.37). However, the distribution of calculated YG resulted in a quadratic effect (P = 0.02) for YG 3 with the control and 500 VITE being greater than the 2 intermediate amounts. However, the percentage of carcasses grading YG 3 or less were not affected by vitamin E supplementation (P = 0.64). No differences were observed in the distribution of quality grades based on marbling scores (P ≥ 0.57). Data from this study suggest that vitamin E supplemented above basal requirements during the last 97 d of the feeding period in finishing diets containing 35% WDGS results in slight to no effect on animal performance or carcass characteristics.     

Species-specific B-cell epitope on the C-terminal region of the alpha antigen from Mycobacterium intracellulare in mice

The alpha antigen, which is an immunodominant antigen, is a 30 kDa protein secreted by mycobacterial species. The C-terminal regions of alpha antigens are quite divergent. We investigated the question of whether the C-terminal regions of Mycobacterium avium alpha antigen (A-alpha), M. intracellulare alpha antigen (I-alpha) and M. bovis BCG alpha antigen (B-alpha) contained species-specific B-cell epitopes. We investigated the reactions of these peptides with anti-A-alpha, anti-I-alpha and anti-B-alpha sera prepared from BALB/c in a Western blot assay and ELISA. The C-terminal regions of I-alpha reacted exclusively with anti-I-alpha serum. The results of the inhibition assay of antibodies binding to I-alpha by peptides of C-A-alpha, C-I-alpha, and C-B-alpha are that only C-I-alpha inhibited the binding of antibodies to C-I-alpha. We found that the C-terminal region was B-cell epitope-specific to I-alpha in BALB/c mice.