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1.
Thirty-one canine cutaneous masses, diagnosed as mast cell tumors (MCT) by histopathologic analysis, were used to evaluate the immunohistochemical pattern of expression of KIT protein (CD117), a type III tyrosine kinase protein involved in mast cell growth and differentiation. Lesions were graded as I (well differentiated), II (intermediate differentiation), or III (poorly differentiated) according to the following morphologic features: invasiveness, cellularity and cellular morphology, mitotic index, and stromal reaction. Immunohistochemical KIT expression was compared with histologic grade and some histomorphologic features (cell differentiation and nuclear grade) evaluated separately. A possible predictive role of biologic behavior in MCTs for KIT expression was also investigated. Immunohistochemical analysis revealed three different patterns of KIT expression: a cytoplasmic diffuse pattern, a membranous pattern with immunostaining located on the cell surface, and a cytoplasmic perinuclear pattern, where KIT expression was detected in the cytoplasm of the neoplastic mast cells, close to the nucleus. Statistical analysis showed a close relationship between different KIT immunohistochemical patterns and histologic grade (P < 0.00000), cell differentiation (P < 0.00000), and nuclear grade (P < 0.0024). According to Kaplan-Meier-estimated survival curves compared by survival analysis, KIT expression was significantly associated with survival time (P = 0.037) but not cancer-free interval (P = 0.50). Similar to other well-known histomorphological features, KIT expression is a useful parameter of malignancy in cutaneous MCTs. KIT expression also predicted the biological behavior of the tumors in this study.  相似文献   
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The changes of cortisol, red blood cells (RBC), hemoglobin (Hb), hematocrit (Hct), heart rate (HR), respiratory rate (RR) and rectal temperature (RT) were evaluated after a reining training session in eight Quarter Horses. All parameters were measured before exercise (T0), immediately after exercise (T1), 1 h after exercise (T2), 2 h after exercise (T3) and 24 h after exercise (T4). One‐way analysis of variance (ANOVA) for repeated measures, followed Bonferroni's post hoc test, showed a significant effect of the reining training session (P < 0.0001) on cortisol, RBC, Hb, Hct, HR, RR and RT. Simple linear regression analysis showed the positive correlation (P < 0.05) between cortisol changes and variations of studied parameters in T1, T3 and T4. Exercise‐induced cortisol concentrations reflect the physiological response of reining training, suggesting that the changes observed are useful to assess the performance in reining horses and their reining training adaptability.  相似文献   
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An 8-month-old, male, crossbreed dog was presented for macroglossia, reduced mandibular extension, ptyalism, dysphagia, and regurgitation. Serum creatine kinase and aspartate aminotransferase activity were markedly increased. Thoracic radiographs showed an axial gastro-esophageal hiatal hernia, diaphragmatic thickening, and asymmetry. Magnetic resonance imaging of the head showed a severely enlarged tongue, symmetric increase in size of the geniohyoid and mylohyoid muscles, and diffuse masticatory hypomyotrophy. Whole-body CT ruled out other musculoskeletal abnormalities and further characterized the radiographic and MRI findings. Muscular histopathology was consistent with Becker muscular dystrophy.  相似文献   
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Summary The occurrence of layers of wood material beneath the soil of the fossil forest of Dunarobba (Italy) has provided the opportunity to study a differently degraded wood formed in the same environment of the fossil forest. The samples of subsoil have almost completely lost their polyose and cellulose fractions and, moreover, were deprived of most of their low and medium MW terpenes so that some phenolic diterpenes were revealed. The identified ones were ferruginol, podocarpodiol, traces of sugiol and a compound whose mass spectrum shows some similarities with that of sugiol. A family of compounds with ketonic structure was also detected: in particular tridecanone, pentadecanone and heptadecanone.Dr. G. Scarascia Mugnozza and Dr. Francesca Bozzano are thanked for fossils donation and Prof. Pasquale Miraglino for mass spectrometry analyses  相似文献   
8.

Background

The authors report the first case of feline gastric actinomycosis associated with infection by Actinomyces hordeovulneris.

Case presentation

A 4-year-old, neutered male, semi-feral European cat, with a 1 year history of chronic vomiting, was referred to the clinic. Abdominal ultrasound examination identified a hypoechoic focal transmural thickening with loss of normal wall layering and hyperechoic speckles at the gastric body. Initial gastroscopic examination showed a tumour-like gastric mass with an ulcerated depression at the level of the greater curvature. Histologic examination of endoscopic biopsy specimens was consistent with a severe lymphoplasmacytic gastritis. After 2 months, due to persistence of abdominal discomfort, surgical exploration and intraoperative sampling of gross abnormalities was recommended. Full thickness gastric wall biopsies, and fine needle aspiration of the gastric thickening and gastric lymph node, were performed. Histopathological examination identified a transmural pyogranulomatous gastritis. Aspirate samples of the gastric wall cultured positive, with colony morphology, biochemical testing and PCR of the 16 s rRNA gene compatible with Actinomyces hordeovulneris. After 4 months of treatment with cefovecin (8 mg/kg subcutaneously every 14 days), the vomiting completely resolved, as well as the ultrasonographic gastric alteration.

Conclusion

This case report of feline gastric actinomycosis, caused by Actinomyces hordeovulneris, suggests that gastric bacterial infection should be considered in cases of focal gastric wall thickening associated with chronic vomiting in the cat, which may otherwise closely resemble neoplastic disease. Once a diagnosis of actinomycosis was obtained, a correct treatment with antibiotic therapy can resolve it.
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A series of N-substituted derivatives of aminomethylenebisphosphonic acid were evaluated as potential inhibitors of delta1-pyrroline-5-carboxylate reductase (EC 1.5.1.2), the enzyme that catalyzes the last step in proline biosynthesis, partially purified from Arabidopsis thaliana suspension cultured cells. At millimolar concentrations, three compounds out of 26 were found to interfere with the catalytic mechanism. One of them, namely, 3,5-dichloropyridyl-aminomethylenebisphosphonic acid, retained such inhibitory activity in the micromolar range. Kinetic analyses ruled out the possibility that the inhibition could simply rely upon the chelating properties of bisphosphonates and showed mechanisms of a noncompetitive type against NADH and an uncompetitive type against delta1-pyrroline-5-carboxylic acid, with KI values of 199 +/- 6 and 10.3 +/- 1.5 microM, respectively. A computer-aided docking analysis, performed on the basis of the crystal structure of the enzyme from Streptococcus pyogenes, suggested that this phosphonate may interact with amino acid residues near the binding site of delta1-pyrroline-5-carboxylic acid, thus blocking the substrate in a pocket and preventing its interaction with NADH. Because in higher plants the step catalyzed by delta1-pyrroline-5-carboxylate reductase is shared by all pathways leading to proline synthesis, such a compound may represent a lead structure to be exploited for the design of new substances endowed with herbicidal activity.  相似文献   
10.
On the basis of the biological activities exhibited by the phenolic constituents of Yucca schidigera, the antioxidant activity of the methanol extract of Yucca gloriosa roots was evaluated in the TEAC assay. The strong activity exerted by this extract prompted investigation of its phenolic constituents, yielding three new phenolic derivatives, gloriosaols C, D, and E, along with gloriosaols A and B previously isolated from Y. gloriosa roots and yuccaols C-E isolated from Y. schidigera. ESIMS and NMR data of gloriosaols C-E closely resembled those reported for gloriosaols A and B, two diasteroisomers characterized by unusual spirostructures. Careful inspection of ROESY spectra revealed that gloriosaols C-E are diastereoisomers of gloriosaols A and B. A possible assignment of the relative configuration of gloriosaols C-E, derived according to an integrated NMR-quantum mechanical (QM) approach, which was already applied to the determination of the stereostructures of gloriosaols A and B, is also proposed. Gloriosaols A-E exhibited potent antioxidant activity measured by the TEAC assay, showing the potential use of Y. gloriosa as a source of antioxidant principles.  相似文献   
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