Biochemical Characterization of Mycoplasma bovirhinis,Mycoplasma dispar and Recent Bovine Isolates of Mycoplasma canis

The pattern and kinetics of substrate utilization by the type strains of Mycoplasma canis, M. bovirhinis and M. dispar and ten recent M. canis isolates from cattle were determined. Metabolism of a range of sugars and organic acids by M. dispar was detectable by measurement of oxygen uptake. Organic acids were not utilized by M. bovirhinis or M. canis, and there was no oxygen uptake during metabolism of glucose or other sugars, as monitored by a pH-change method. The M. canis strains varied in their ability to metabolize sugars; seven of the isolates from cattle had the distinctive ability to metabolize sucrose, and one isolate, plus the type strain (from a dog), metabolized N-acetylglucosamine. The M. bovirhinis strain metabolized maltose. However, all the test strains oxidized glycerol at high rates and with a high affinity. Oxidation of glycerol has been reported for other mycoplasmas from the bovine respiratory tract and leads to the production of hydrogen peroxide, a potential virulence factor.     

Reducing greenhouse gas emissions from deforestation and forest degradation: global land-use implications

Recent climate talks in Bali have made progress toward action on deforestation and forest degradation in developing countries, within the anticipated post-Kyoto emissions reduction agreements. As a result of such action, many forests will be better protected, but some land-use change will be displaced to other locations. The demonstration phase launched at Bali offers an opportunity to examine potential outcomes for biodiversity and ecosystem services. Research will be needed into selection of priority areas for reducing emissions from deforestation and forest degradation to deliver multiple benefits, on-the-ground methods to best ensure these benefits, and minimization of displaced land-use change into nontarget countries and ecosystems, including through revised conservation investments.     

利用10B示踪法研究栗钙土中硼肥的生物效应(简报)

硼对植物营养生理的作用,不仅能使植物细胞壁坚韧与木质化,促进与增强植物的抗逆性(抗旱性与抗寒性),而且能促进植物根系发育及糖在体内的运输等。但是有关硼肥营养机理的研究报道较少,尤其是利用~(10)B 示踪研究植物硼肥营养及其在土壤中的转化,更是罕见。为此,我们应用~(10)B 研究了球茎甘蓝在栗钙土上对硼肥的吸收利用,为栗钙土的硼肥使     

Enzyme-linked immunosorbent assay for the detection of yessotoxin and its analogues

Polyclonal antibodies were produced for the development of competitive enzyme-linked immunoassays for use in quantifying yessotoxins in shellfish, algal cells, and culture supernatants. Immunizing and plate coating antigens were prepared by derivatization of yessotoxin either by ozonolysis or bromination and conjugation to proteins. Two assays that were the most sensitive for yessotoxin were optimized and characterized. Cross-reactivity studies indicated that the antibodies raised have broad specificity and that binding to analogues was strongly affected by changes to the A-ring and, to a lesser extent, the K-ring regions of the toxin molecule. ELISA provides a sensitive and rapid analytical method that is suitable for screening large numbers of samples and detects all the yessotoxin analogues that the European Commission currently requires shellfish to be tested for. The assay limit of quantitation for yessotoxin in whole shellfish flesh is 75 microg/kg; therefore, assay sensitivity is sufficient to measure toxin levels well below the maximum permitted level set by the European Commission. The antibodies produced can be used in additional applications such as the immunolocalization of yessotoxins in shellfish and preparation of immunoaffinity columns.     

Canine nasal septum deviation can be a normal variation and correlates with increasing skull indices

Nasal septal deviation has been studied in relation to nasal pathology and mass effect in dogs. The purpose of this retrospective, cross‐sectional study was to compare the prevalence of nasal septal deviation in dogs with rhinitis, neoplasia, and those without nasal pathology based on the facial index, skull index, and cranial index. Computed tomographic studies of the nasal cavities of dogs performed over a 5‐year period were retrospectively reviewed. This study had 233 dogs meeting the inclusion criteria with 135 dogs with no nasal pathology, 63 dogs with nasal neoplasia, and 35 dogs with rhinitis. The prevalence of nasal septal deviation, the angle, maximum distance, and longitudinal extent of deviation were recorded, as well as measurements to calculate the facial index, cranial index, and skull index. The results showed no difference in the prevalence of nasal septal deviation between dogs with nasal pathology and those without. The mean longitudinal extent of deviation and maximum distance of deviation was statistically greater for those with neoplasia compared to those with rhinitis and without nasal pathology. The longitudinal extent of deviation was inversely proportional to the cranial index, facial index, and skull index. The angle of deviation was directly proportional to the facial index and skull index. In conclusion, nasal septal deviation is an anatomic variant in different breeds of dogs with no predilection based on nasal pathology. Nasal septal deviation should be interpreted cautiously in the assessment of canine nasal disease.     

Constitution of stable artificial oil bodies with triacylglycerol, phospholipid, and caleosin

Seed oil bodies are lipid storage organelles of 0.5-2 microm in diameter and comprise a triacylglycerol matrix shielded by a monolayer of phospholipids and proteins. These proteins include abundant structural proteins, oleosins, and at least two minor proteins termed caleosin and steroleosin. This study examined if artificial oil bodies (AOBs) composed of triacylglycerol and phospholipid could be stabilized by oleosin, caleosin, or steroleosin. Our results showed that stabilization effects could be realized by oleosin or caleosin but not by steroleosin. The sizes of the AOBs constituted with oleosin (0.5-2 microm) or caleosin (50-200 nm) were similar to or 10 times smaller than those of the native oil bodies. Recombinant caleosin expressed in Escherichia coli also encapsulated AOBs with a size, topology, and stability comparable to those encapsulated with native caleosin. A proteinase K digestion indicated that caleosin anchored the AOBs via its central hydrophobic domain of approximately 4 kDa. Isoelectrofocusing revealed that the isoelectric point of the caleosin-stabilized AOBs was pH 4.0. Aggregation of AOBs was observed at a pH lower than 4.5; thus, their stability and integrity were presumably contributed by surface caleosin via electronegative repulsion and steric hindrance. The caleosin-stabilized AOBs were thermostable up to 70 degrees C and potentially useful for biotechnological applications.