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Fusarium species, which are typically associated with fusarium head blight of cereals, were isolated, identified and enumerated from residues collected in 239 cereal, 71 corn and 201 grass fields/sites in Alberta from 2001 to 2004. Cereal and grass residues were collected in the Peace River, central and southern regions of Alberta, while corn samples were collected from central and southern Alberta. The most frequently recovered species were F. avenaceum and F. culmorum followed by F. pseudograminearum and F. graminearum. Outside of southern Alberta, the most important causal agent of fusarium head blight, F. graminearum, was isolated at low levels in only one of 163 cereal fields, and was not isolated from the 39 corn fields or 105 grass sites surveyed. In contrast, in southern Alberta, F. graminearum was isolated from cereal residues in 10 of 76 cereal fields. Relatively high levels (46-50%) of node and crown infection occurred in one southern Alberta field in 2003. Fusarium graminearum was most common in corn residues from southern Alberta, being isolated from 24 of 32 fields, with average incidences of node infection ranging from 10 to 60% within these fields. In contrast, only three of 96 grass sites in southern Alberta had detectable, albeit low, levels of F. graminearum. The infrequent occurrence of F. graminearum, especially in central Alberta, and the Peace River region, suggests that Alberta's agricultural industry should continue to monitor its presence in grain and crop residues, while attempting to limit further build up and spread of this pathogen. [ABSTRACT FROM AUTHOR]

The article reports on a study in which pathogenicity tests were performed under controlled conditions to contrast aggressiveness within and between isolates of Fusarium graminearum and F. pseudograminearum in causing soybean root rot. All isolates were found to cause visible infection within 10 days after inoculation, but F. graminearum isolates were much more aggressive than those of F. pseudograminearum.

The article assess the capability of Canadian isolates of Fusarium pseudograminearum (F. pseudograminearum), collected from seed and vegetative cereal parts and other gramineae grown in western Canada, to produce toxins in culture. F. pseudograminearum has been considered as the most important causal agent of Fusarium diseases of wheat in Australia due to its capacity to infect the head causing Fusarium head blight.

The article focuses on the studies that examines the red spring and amber durum wheat grown in western Canada from 2000 to 2002. The wheat seeds were analyzed for fungal infection and contamination by mycotoxins, such as by trichothecenes and moniliformin. The average levels of several fusariotoxins in wheat were determined. It shows that low levels of moniliformin were found in wheat composite samples.

Fusarium graminearum, Fusarium culmorum, and Fusarium avenaceum, isolated from Fusarium-damaged wheat harvested in western Canada, were cultured and evaluated for mycotoxin production. Extracts of the culture media were assayed for trichothecenes by gas chromatography-mass spectrometry and for moniliformin by liquid chromatography. Deoxynivalenol (DON) was found in 28 of 42 isolates of F. graminearum and 42 of 42 isolates of F. culmorum at levels ranging from 0.5 to 25.0 microg/g. 15-AcetylDON was found in 28 of 42 isolates of F. graminearum at levels ranging from 1.0 to 7.1 microg/g. 3-AcetylDON was found in 41 of 42 isolates of F. culmorum at levels ranging from 0.8 to 13.0 microg/g. Several other trichothecenes were assayed but not detected in the culture medium. Moniliformin was present in 40 of 42 isolates of F. avenaceum at levels ranging from 1.3 to 138.1 microg/g, but was not present in any of the isolates of F. graminearum or F. culmorum.

Soluble extracellular components (exoantigens) from cultures of Fusarium graminearum and F. sporotrichioides were used to produce antisera from chickens for an indirect enzyme immunoassay. This immunoassay was used to estimate Fusarium exoantigen levels in 40 samples of fusarium head blight-infected hard red spring wheat from Manitoba, and in 50 samples of infected soft white winter wheat from Ontario. These wheat samples were also assayed for deoxynivalenol (DON), the predominant Fusarium mycotoxin, and for ergosterol, a metabolite reflecting fungal biomass. Using F. sporotrichioides antisera, the linear correlations between exoantigen level and DON content for the hard and soft wheats had coefficients of 0.80 and 0.76, respectively. With the same antisera, linear correlations between exoantigen level and total ergosterol concentration for the hard and soft wheats had coefficients of 0.66 and 0.81, respectively.

Production of aflatoxins, sterigmatocystin, citrinin, and ochratoxin A by Aspergillus and Penicillium species on agar in 50-ml flasks after 21 days was detected and confirmed by thin-layer chromatography. Toxins were extracted with 2.5 ml of acidified methylene chloride for 20 to 60 min. Mycotoxin concentrations were estimated by liquid chromatography. Addition of formic acid to the methylene chloride extraction solvent effected an increase in recovery of ochratoxin A from Czapek-yeast (CY) agar from 20% to 91%. Recoveries of added mycotoxins were generally higher from CY agar than from yeast extract-sucrose (YES) agar and ranged from 11% (citrinin from YES agar) to 91% (ochratoxin A from CY agar). The method described is convenient, rapid, and reproducible, since it samples the entire culture surface. Human exposure to volatile solvents is also minimized.

Tebufelone is a novel nonsteroidal anti-inflammatory drug (NSAID), of the di-tert-butylphenol (DTBP) class, which displays potent anti-inflammatory, analgesic and anti-pyretic properties in a variety of animal models. In this report, the effects of Tebufelone on arachidonic acid (AA) metabolism are reviewed. Tebufelone potently inhibits the formation of prostaglandins (PGE2) a key mediator of pain and inflammation, in isolated enzyme preparations (IC50 = 1.5 microM, KI = 0.35 microM), two in vitro cellular systems: rat peritoneal macrophages (IC50 = 0.02 microM) and human whole blood (IC50 = 0.08 microM), and ex vivo in man. In addition to PGE2 inhibition, which is common to all NSAIDs, higher concentrations of Tebufelone block the in vitro formation of products of the lipoxygenase pathway [leukotrienes (LTB4)] in rat macrophages (IC50 = 20 microM) and human whole blood (IC50 = 22 microM). Substrate incorporation studies (14C-AA) indicate that Tebufelone reversibly inhibits cyclooxygenase (CO) and 5-lipoxygenase (5-LO) enzymes rather than regulating the release of AA. Tebufelone was shown to be a more potent CO inhibitor than indomethacin and a less potent 5-LO inhibitor than RG-5901. Comparisons to structurally related compounds under development (E-5110, Esai; KME-4, Kanagafuchi), found Tebufelone to be the most potent CO inhibitor in vitro. All three DTBP compounds were equipotent 5-LO inhibitors. It is likely that Tebufelone's inhibitory effects on AA metabolism are, in part, responsible for its in vivo efficacy and enhanced safety profile.

A case of carcinoma ex pleomorphic adenoma of the palate and maxillary sinus is reported. Unlike most such cases, there were two distinct malignant components: adenoid cystic carcinoma and adenocarcinoma. The computerized tomography of this lesion is described.