Equine atypical myopathy caused by hypoglycin A intoxication associated with ingestion of sycamore maple tree seeds.

REASONS FOR PERFORMING STUDY: Evidence suggest there is a link between equine atypical myopathy (EAM) and ingestion of sycamore maple tree seeds. OBJECTIVES: To further evaluate the hypothesis that the ingestion of hypoglycin A (HGA) containing sycamore maple tree seeds causes acquired multiple acyl-CoA dehydrogenase deficiency and might be associated with the clinical and pathological signs of EAM. STUDY DESIGN: Case report. METHODS: Necropsy and histopathology, using hematoxylin and eosin and Sudan III stains, were performed on a 2.5-year-old mare that died following the development of clinical signs of progressive muscle stiffness and recumbency. Prior to death, the animal ingested sycamore maple tree seeds (Acer pseudoplatanus). Detection of metabolites in blood and urine obtained post mortem was performed by rapid ultra-performance liquid chromatography-tandem mass spectrometry. Data from this case were compared with 3 geldings with no clinical history of myopathy. RESULTS: Macroscopic examination revealed fragments of maple tree seeds in the stomach and severe myopathy of several muscle groups including Mm. intercostales, deltoidei and trapezii. Histologically, the affected muscles showed severe, acute rhabdomyolysis with extensive accumulation of finely dispersed fat droplets in the cytoplasm of degenerated skeletal muscle cells not present in controls. Urine and serum concentrations of several acyl carnitines and acyl glycines were increased, and both contained metabolites of HGA, a toxic amino acid present in sycamore maple tree seeds. CONCLUSIONS: The study supports the hypothesis that ingestion of HGA-containing maple tree seeds may cause EAM due to acquired multiple acyl-CoA dehydrogenase deficiency.

[Prognosis of canine oral (gingival) squamous cell carcinoma after surgical therapy. A retrospective analysis in 40 patients]. / Prognose oraler (gingivaler) Plattenepithelkarzinome beim Hund nach chirurgischer Therapie. Eine retrospektive Untersuchung bei 40 Patienten.

OBJECTIVE: Retrospective analysis of dogs with gingival squamous cell carcinoma (SCC) surgically treated using jaw resection. Material and me- thods: A total of 40 dogs were enrolled in the study. Dogs with incomplete tumour resection or metastases were subjected to adjuvant chemotherapy using carboplatin. Breed, age, tumour localisation, postsurgical complications, survival times and prognostic factors were evaluated. RESULTS: There were no breed predispositions. The median age was 9.5 years (mean 8.6 years; range 0.5-15.5 years). At the time of presentation, two dogs (5%) had lymph node metastases (N1). The median survival time (ST) of all the patients was 44.8 months. In 15 patients, the tumour was located in the maxilla, whereas 25 dogs had a mandibular tumour location. The median ST in dogs with maxillary tumours was 39 months (95% confidence interval [CI] 24 months), while patients with maxillary tumours survived a median of 43 months (95% CI 33-70 months). There was no significant difference in the ST in patients with maxillary versus man- dibular tumours (p = 0.985). On multivariate analysis, only the tumour stage was found to be significantly associated with survival (p = 0.0047). Patients with stage N0 survived a median of 44 months (95% CI 36-80 months). The two dogs with lymph node metastasis (N1) sur- vived 18 and 70 months following jaw resection and carboplatin chemotherapy, respectively. According to the histological findings, tumour resection was incomplete in five patients. These dogs received adjuvant carboplatin chemotherapy, resulting in an ST of between 6 and 146 months. CONCLUSION AND CLINICAL RELEVANCE: Prognosis depends on the tumour stage, while for complete local excision of the affected jaw segment a good prognosis can be given and the majority of the patients can be cured. The supposedly more malignant behaviour of gingival SCCs located in the caudal aspects of the oral cavity could not be confirmed. Patients with metastasis of the local lymph nodes can achieve acceptable survival times. Jaw resections have low complication rates and a good functional outcome.

The ferulic acid esterases of Chrysosporium lucknowense C1: purification, characterization and their potential application in biorefinery.

Three ferulic acid esterases from the filamentous fungus Chrysosporium lucknowense C1 were purified and characterized. The enzymes were most active at neutral pH and temperatures up to 45 °C. All enzymes released ferulic acid and p-coumaric acid from a soluble corn fibre fraction. Ferulic acid esterases FaeA1 and FaeA2 could also release complex dehydrodiferulic acids and dehydrotriferulic acids from corn fibre oligomers, but released only 20% of all ferulic acid present in sugar beet pectin oligomers. Ferulic acid esterase FaeB2 released almost no complex ferulic acid oligomers from corn fibre oligomers, but 60% of all ferulic acid from sugar beet pectin oligomers. The ferulic acid esterases were classified based on both, sequence similarity and their activities toward synthetic substrates. The type A ferulic acid esterases FaeA1 and FaeA2 are the first members of the phylogenetic subfamily 5 to be biochemically characterized. Type B ferulic acid esterase FaeB2 is a member of subfamily 6.

Mode of action of Chrysosporium lucknowense C1 α-l-arabinohydrolases.

The mode of action of four Chrysosporium lucknowense C1 α-L-arabinohydrolases was determined to enable controlled and effective degradation of arabinan. The active site of endoarabinanase Abn1 has at least six subsites, of which the subsites -1 to +2 have to be occupied for hydrolysis. Abn1 was able to hydrolyze a branched arabinohexaose with a double substituted arabinose at subsite -2. The exo acting enzymes Abn2, Abn4 and Abf3 release arabinobiose (Abn2) and arabinose (Abn4 and Abf3) from the non-reducing end of reduced arabinose oligomers. Abn2 binds the two arabinose units only at the subsites -1 and -2. Abf3 prefers small oligomers over large oligomers. It is able to hydrolyze all linkages present in beet arabinan, including the linkages of double substituted residues. Abn4 is more active towards polymeric substrate and releases arabinose monomers from single substituted arabinose residues. Depending on the combination of the enzymes, the C1 arabinohydrolases can be used to effectively release branched arabinose oligomers and/or arabinose monomers.

Chrysosporium lucknowense arabinohydrolases effectively degrade sugar beet arabinan.

The filamentous fungus Chrysosporium lucknowense (C1) is a rich source of cell wall degrading enzymes. In the present paper four arabinose releasing enzymes from C1 were characterized, among them one endoarabinanase, two arabinofuranosidases and one exoarabinanase. Combinations of these enzymes released up to 80% of the arabinose present in sugar beet arabinan to fermentable monosugars. Besides the main product arabinobiose, unknown arabinose oligomers are produced from highly branched arabinan when endoarabinanase was combined with exoarabinanase and/or arabinofuranosidase. All described arabinose releasing enzymes are temperature stable up to 50 degrees C and have a broad pH stability. This makes C1 arabinohydrolases suitable for many biotechnical applications, like co-fermentation bioethanol production.

[Tonsillar squamous cell carcinoma in the dog. A retrospective study of 33 cases]. / Tonsilläre Plattenepithelkarzinome beim Hund. Eine retrospektive Untersuchung von 33 Patienten.

OBJECTIVE: Retrospective evaluation of clinical findings in 33 dogs with tonsillar squamous cell carcinomas. MATERIAL AND METHODS: At the owners' request 9 patients were euthanized after diagnosis. 24 treated patients were grouped into six categories depending on the type of therapy: 1. tonsillectomy and NSAID (Piroxicam or Metacam) (n=10); 2. tonsillectomy, NSAID, and palliative radiation (24-30Gy in 3-5 fractions) (n=4); 3. tonsillectomy, NSAID, palliative radiation, and chemotherapy (5´ Carboplatin 280-300mg/m2 BSA) (n=3); 4. NSAID, palliative radiation, and chemotherapy (n=1); 5. NSAID alone (n=5), 6. tonsillectomy alone (n=1). RESULTS: There were no breed predispositions but medium sized (10-20kg; 43%) and large dogs (>20kg; 20%), and males (n=22; 71%) were overrepresented. The average age was 10.7years (range, 6.5-14.5years). At the first presentation, 22 of the 33 dogs (67%) had lymph node metastasis. None of the dogs had lung metastasis at the time of diagnosis, as determined by three view chest X-rays. The best survival times (ST) were achieved in groups 2 and 3 with three of seven patients living longer than 1year. Patients without lymph node metastasis had a trend for longer survival times, independent of the type of therapy. Treated patients with lymph node metastasis (n=17) had a mean and median ST of 9.5 and 4months, respectively. Only two dogs survived longer than 1year. Dogs without lymph node metastasis had a mean and median ST of 17.7 and 12 months, respectively; the ST for four of the eight dogs exceeded 1year, two survived longer than 2years. CONCLUSION: It could be confirmed that tonsillar squamous cell carcinomas are aggressive tumours with a high rate of cervical lymph node metastasis. In most cases with metastasis the survival times were relatively short, irrespective of treatment. In early stages of the disease however, good survival times could be achieved using surgical debulking followed by multimodality treatment. CLINICAL RELEVANCE: In squamous cell carcinoma of the tonsils thorough staging is mandatory due to the high metastatic potential of the tumour. Verification of metastasis carries a poor prognosis. Further studies are required to find the best treatment (combination) for these patients.