New insights into radiata pine seedling root infection by Fusarium circinatum

Pine root infection by Fusarium circinatum has been reported in the literature, but the underlying pathogenic interaction is poorly understood. A green fluorescent protein (GFP)‐tagged F. circinatum isolate, together with confocal microscopy, was used in order to monitor the events associated with root infection of Pinus radiata seedlings. It was found that in order to reach and successfully infect pine roots, F. circinatum employed features that are similar to those previously described for other root‐infecting pathogens, such as mycelial strands, single runner hyphae and simple hyphopodia as well as other features that are reminiscent of those that are known to be involved in biotrophic invasion, such as bulbous invasive hyphae and filamentous invasive hyphae. Abundant sporulation was observed at the root surface as well as inside tracheids both in roots and in the root collar region. The fungus can spread from the roots to the aerial parts of the plant, and once there, colonization appears to be similar to the process that occurs when the pathogen is inoculated in the stem. Wilting symptoms and plant demise may be the result of a reduction in water uptake by roots and of the blockage of the vascular system by fungal hyphae and resin.     

Application of long‐chain alcohols as diet‐composition markers in sheep fed on grass–white clover and heather–gorse plant species

Utilization of long‐chain alcohols (LCOH) as diet‐composition markers in sheep consuming six diets composed of improved pasture species (Lolium perenne and Trifolium repens) with heather–gorse components (Erica spp., Calluna vulgaris and Ulex gallii) was evaluated. Twenty‐four adult cross‐bred sheep were housed in individual stalls. Diet composition was estimated from LCOH concentrations, combined or not with alkanes and long‐chain fatty acid (LCFA) data using least‐squares procedures. Prior to calculations, faecal concentrations were corrected using mean treatment (faecal recovery 1, FR1) recoveries and mean recoveries across diets (FR2). Estimates were compared with those obtained without faecal correction (FR0) and known values. Large differences between plant species and plant parts were found in LCOH patterns and total LCOH concentrations. LCOH provided complementary information to that given by alkanes and LCFA. Even‐chain LCOH comprised the largest fraction, representing on average 0·894 of total concentrations. Faecal recovery was incomplete and tended to increase with carbon‐chain length (CCL) in a curvilinear manner (FR = ?7·872 + 0·580 × CCL ? 0·010 × CCL²; P < 0·001; r² = 0·752). Diet composition influenced (P < 0·001) LCOH recovery, although variability within (CV of 9·0%) and between (CV of 13·3%) diets was low. Accuracy of estimates was influenced (P < 0·001) by faecal‐correction method and markers used, and the best estimate was obtained combining LCOH and alkanes. Improvement in estimate accuracy can be achieved if suitable correction of LCOH faecal concentrations is performed prior to calculations. Results indicated that LCOH showed lower dependence than alkanes and LCFA on the use of accurate faecal‐correction data.     

Antitumor and Antimicrobial Potential of Bromoditerpenes Isolated from the Red Alga,Sphaerococcus coronopifolius

Cancer and infectious diseases continue to be a major public health problem, and new drugs are necessary. As marine organisms are well known to provide a wide range of original compounds, the aim of this study was to investigate the bioactivity of the main constituents of the cosmopolitan red alga, Sphaerococcus coronopifolius. The structure of several bromoditerpenes was determined by extensive spectroscopic analysis and comparison with literature data. Five molecules were isolated and characterized which include a new brominated diterpene belonging to the rare dactylomelane family and named sphaerodactylomelol (1), along with four already known sphaerane bromoditerpenes (2–5). Antitumor activity was assessed by cytotoxicity and anti-proliferative assays on an in vitro model of human hepatocellular carcinoma (HepG-2 cells). Antimicrobial activity was evaluated against four pathogenic microorganisms: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans. Compound 4 exhibited the highest antimicrobial activity against S. aureus (IC₅₀ 6.35 µM) and compound 5 the highest anti-proliferative activity on HepG-2 cells (IC₅₀ 42.9 µM). The new diterpene, sphaerodactylomelol (1), induced inhibition of cell proliferation (IC₅₀ 280 µM) and cytotoxicity (IC₅₀ 720 µM) on HepG-2 cells and showed antimicrobial activity against S. aureus (IC₅₀ 96.3 µM).     

2008年霉菌毒素普查项目报告

黄曲霉毒素B1、玉米赤霉烯酮、呕吐毒素、烟曲霉毒素、赭曲霉毒素A以及T-2毒素,这些霉菌毒素名称无疑会引起你的警惕,它们是在畜牧生产中最常见、最重要的几种霉菌毒素。尽管这些霉菌毒素是在作物生产周期的不同阶段产生的。玉米赤霉烯酮、烟曲霉毒素和单端孢菌霉烯毒素（呕吐毒素和T-2毒素）等镰刀霉菌毒素主要在田间产生,     

The Influence of Oxygen Tension on Cumulus Cell Viability of Canine COCs Matured in High-Glucose Medium

High in vitro oxygen (O₂) tensions are associated with enhanced levels of reactive oxygen species and cumulus oocyte complex (COC) apoptosis. The objective of this study was to determine the influence of O₂ tension on cumulus cell (CC) viability from canine oocytes. Cumulus oocyte complexes were distributed into three groups (CG, T20 and T5) and two O₂ tension levels (20% and 5%). The control group (CG) was matured in vitro in a humidified atmosphere with 5% CO₂ in air in TCM199 with 26.19 m m sodium bicarbonate, 10% (v/v) foetal calf serum (FCS), 0.10 m m gentamicin, 0.20 m m pyruvic acid, 20 μg/ml oestradiol, 0.5 μg/ml follicle-stimulating hormone, 0.03 IU/ml human chorionic gonadotropin, and 1.0 μg/ml human somatotropin. Groups T20 and T5 were matured under 20% or 5% O₂ tensions respectively in a high-glucose medium, without FCS. T20 and T5 were as CG, and supplemented with 0.1% Polyvinyl Alcohol, and 5.5 m m glucose. After 48 h of IVM, CCs from COCs were stained with propidium iodide (1.50 m m ). The results showed that viability of CCs (cytoplasmic features and nuclear morphological integrity) was different for the three groups. Rates of apoptosis were at 57.9% (521/900) for CG, 54.4% (490/900) for T20 and 38.9% (350/900) for T5 (p < 0.001). Predominant features in apoptotic cells (n = 1361) were DNA nuclear fragments (94.0%). It was concluded that CCs of canine COCs cultured in high-glucose medium showed significantly less apoptosis than those cultured in medium with FCS. Low O₂ tension was efficient in reducing apoptosis in canine CCs.     

Outcomes of Heimlich valve drainage in dogs

Objective and design   Retrospective study of the outcomes of Heimlich valve drainage in dogs.
Procedure   Medical records of the past 3 years were retrospectively reviewed. Heimlich valve drainage was used in 34 dogs (median body weight 30 ± 5 kg): lobectomy (n = 15), pneumonectomy (n = 9), intrathoracic oesophageal surgery (n = 2), diaphragmatic hernia repair (n = 1), traumatic open pneumothorax (n = 2), bilobectomy (n = 2), ligation of the thoracic duct (n = 1), and chylothorax and pneumothorax (n = 1 each). Evacuation of air and/or fluid from the pleural cavity was performed with the Heimlich valve following thoracostomy tube insertion. During drainage, the dogs were closely monitored for possible respiratory failure. Termination of Heimlich valve drainage was controlled with underwater seal drainage and assessed with thoracic radiography.
Results   Negative intrathoracic pressure was provided in 29 dogs without any complications. Post pneumonectomy respiratory syncope and post lobectomy massive hemothorax, which did not originate from the Heimlich valve, were the only postoperative complications. Dysfunction of the valve diaphragm, open pneumothorax and intrathoracic localisation of an acute gastric dilatation–volvulus syndrome caused by a left-sided diaphragmatic hernia following pneumonectomy were the Heimlich valve drainage complications.
Conclusions   The Heimlich valve can be used as a continuous drainage device in dogs, but the complications reported here should be considered by veterinary practitioners.