对鸡传染性喉气管炎SA2分离株的初探

ＳＡ２株是鸡传染性喉气管炎的自然弱毒株，通过使用不同的实验室手段已分离到此毒株，经繁殖与复壮，此株生长稳定。经过对分离株的鉴定，鸡胚和雏鸡的毒性检测。ＥＩＤ５０计算及对不同日龄鸡的免疫应签检测和攻毒实验，表明该株保持了原毒株特性，毒性低，副作用小，具有良好的免疫效果，为研究开发此株疫苗奠定了基础。     

Development of a bead-based multiplex PCR assay for the simultaneous detection of multiple Mycoplasma species

We describe the development and analytical validation of a 7-plex polymerase chain reaction assay coupled to a bead-based liquid suspension array for detection of multiple ruminant Mycoplasma spp. The assay employs a combination of newly designed and previously validated primer-probe sets that target genetic loci specific for Mycoplasma bovis, Mycoplasma mycoides cluster, Mycoplasma mycoides subsp. mycoides SC (MmmSC) and Mycoplasma capricolum subspecies capripneumoniae (Mccp). Analytical sensitivity for the targeted Mycoplasma species ranged from 10 fg to 1 pg of purified gDNA extracted from broth cultures (approximately 8-800 MmmSC genome equivalents). In silico comparison of primers and probes, and analytical assessment with a range of near-neighbor Mycoplasma species and multiple bacterial respiratory pathogens demonstrated 100% analytical specificity of the assay. To assess assay performance and diagnostic specificity, 192 bovine respiratory samples were analyzed by incorporating a high throughput DNA extraction platform. The assay correctly classified all samples as negative for MmmSC or Mccp. All 33 field samples confirmed as positive for M. bovis by sequencing the uvrC gene were positive in the assay. The results from this study indicate that the bead-based liquid suspension array will provide a reliable, analytically sensitive and specific platform to simultaneously interrogate ruminant respiratory samples for multiple Mycoplasma species, including M. mycoides cluster organisms that are exotic to the United States. Sequential addition of primer-probe sets to the assay did not significantly impact analytical sensitivity of individual primer-probe combinations, suggesting that expanding the assay to include more Mycoplasma species will not compromise overall performance.     

Moment of addition of LH to the culture medium improves in vitro survival and development of secondary goat pre-antral follicles

The present study investigated the effects of time of addition of luteinizing hormone (LH) to culture medium on the in vitro development of caprine pre-antral follicles. Pre-antral follicles (≥ 150 μm) were isolated from fragments of the goat ovarian cortex and individually cultured for 18 days in the absence (control) or presence of 100 ng/ml LH, added on days 0, 6 or 12 of culture. Follicular development was assessed based on antral cavity formation, increased follicular diameter as well as follicular and fully grown oocyte (>110 μm) viability. The results showed that after 18 days of culture, the percentage of surviving follicles in the control treatment was significantly lower when compared to other treatments (p < 0.05). There were no significant differences in antrum formation, follicular diameter and oocyte viability. The addition of LH at D6 of culture significantly increased the rates of oocytes ≥ 110 μm and the resumption of meiosis (p < 0.05). In contrast, when LH was added at the onset of culture, only germinal vesicle oocytes were obtained. In conclusion, the moment of addition of LH to the culture medium affects the performance of in vitro culture of caprine pre-antral follicles. The addition of LH to the medium from day 6 of culture onward improved the rates of follicular survival, as well as the ability of oocytes to resume meiosis. However, prolonged exposure to LH (addition at the onset of culture onward) showed detrimental effects for the meiotic resumption.     

Increasing soy isoflavonoid content and diversity by simultaneous malting and challenging by a fungus to modulate estrogenicity

Soybeans were germinated on a kilogram-scale, by the application of malting technology used in the brewing industry, and concomitantly challenged with Rhizopus microsporus var. oryzae. In a time-course experiment, samples were taken every 24 h for 10 days, and the isoflavonoid profile was analyzed by RP-UHPLC-MS. Upon induction with R. microsporus, the isoflavonoid composition changed drastically with the formation of phytoalexins belonging to the subclasses of the pterocarpans and coumestans and by prenylation of the various isoflavonoids. The pterocarpan content stabilized at 2.24 mg of daidzein equivalents (DE) per g after ～9 days. The levels of the less common glyceofuran, glyceollin IV, and V/VI ranged from 0.18 to 0.35 mg DE/g and were comparable to those of the more commonly reported glyceollins I, II, and III (0.22-0.32 mg DE/g) and glycinol (0.42 mg DE/g). The content of prenylated isoflavones after the induction process was 0.30 mg DE/g. The total isoflavonoid content increased by a factor of 10-12 on DW basis after 9 days, which was suggested to be ascribable to de novo synthesis. These changes were accompanied by a gradual increase in agonistic activity of the extracts toward both the estrogen receptor α (ERα) and ERβ during the 10-day induction, with a more pronounced activity toward ERβ. Thus, the induction process yielded a completely different spectrum of isoflavonoids, with a much higher bioactivity toward the estrogen receptors. This, together with the over 10-fold increase in potential bioactives, offers promising perspectives for producing more, novel, and higher potency nutraceuticals by malting under stressed conditions.     

Correlations between pulp properties of eucalyptus clones and leaf volatiles using automated solid-phase microextraction

Analysis of biogenic volatile organic compounds (BVOC) of 14 Eucalyptus clones has been performed using an automated headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography (GC)/ion trap mass spectrometry (ITMS) method. Correlations between pulp properties of Eucalyptus clones and the BVOC of their leaf headspaces were studied. The compounds alpha-terpineol and the sesquiterpene beta-eudesmol were positively correlated with S5, a property related to the hemicelluose content in the pulp. Qualitative results obtained with automated HS-SPME were sufficient to group together the same species and related hybrids through cluster analysis and were confirmed through principal component analysis. A preliminary separation of the essential oils of Eucalyptus dunnii through comprehensive two-dimensional gas chromatography (GC x GC) showed approximately 580 peaks compared to approximately 60 in a typical GC/ITMS first-dimension chromatogram. The potential of HS-SPME coupled to GC x GC to improve the separation of Eucalyptus volatiles and other plant essential oils looks extremely promising for new applications of unsupervised learning methods.     

Polywater: proton nuclear magnetic resonance spectrum

In the presence of water, the resonance of the strongly hydrogenbonded protons characteristic of polywater appears at 5 parts per million lower applied magnetic field than water. Polywater made by a new method confirms the infrared spectrum reported originally.     

Characterization of plutonium in maxey flats radioactive trench leachates

Plutonium in trench leachates at the Maxey Flats radioactive waste disposal site exists as dissolved species, primarily complexes of the tetravalent ion with strong organic ligands such as ethylenediaminetetraacetic acid. The complexes are not sorbed well by sediment and are only partly precipitated by ferric hydroxide. These results indicate the importance of isolating radioactive waste from organic matter.