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Novel tricyclic 3,3a,5,9b-tetrahydro-2H-furo[3,2-c][2]benzopyran (TFB) derivatives were synthesized, and their herbicidal activities were elucidated. They were synthesized from D-glucose as a natural chiral source. The formation of the TFB skeleton was achieved by a Friedel-Crafts type intramolecular cyclization of methyl 5-deoxy-2,3-O-dibenzyl-5-C-methyl-D-xylofranosides. The intramolecular cyclization was dependent upon the electronic effects of the substituents at the C-2 benzyloxy group of methyl xylofranosides. Some TFBs exhibited a remarkable herbicidal activity to annual paddy weeds, such as Echinochloa sp, without injury to the rice.  相似文献   
124.
To evaluate the clinical usefulness of tissue and serum gelatinase activity as a prognostic marker of canine tumors, tissue samples from 60 tumors and corresponding serum samples from the same animals were collected at the time of biopsy and surgery. On the basis of histopathology and clinical aggressiveness of metastasis and recurrence (MR), the cases were divided into 6 categories: non-inflammatory (Inf(-)) and inflammatory (Inf(+)) benign, and the Inf(-) MR(-), Inf(-) MR(+), Inf(+) MR(-), and Inf(+) MR(+) malignant. Gelatinase activity was determined semi-quantitatively using gelatin zymogram with a gelatinase standard from cultured canine peripheral blood mononuclear cells stimulated with lipopolysaccharide. No significant difference in gelatinase activities in tissue extracts was evident between the benign and malignant tumors. Inf(+) benign tumors, as well as Inf(-) MR(+), Inf(+) MR(-) and Inf(+) MR(+) malignant tumors, showed significantly higher tissue gelatinase activity than Inf(-) benign. The tissue activity in Inf(-) MR(-) malignant was significantly lower than in Inf(+) MR(-) and Inf(+) MR(+) malignant. The serum activity was significantly higher in the malignant cases than in the control and the benign. Inf(-) MR(+), Inf(+) MR(-) and Inf(+) MR(+) malignant tumors induced significantly higher gelatinase activity in serum than Inf(-) benign tumors. Gelatinase activity in serum was positively correlated with that in tumor extracts. Increased gelatinase in tumor tissue and serum may be correlated with inflammation as well as tumor aggressiveness, and thus should be used in combination with histopathology for predicting tumor metastasis or recurrence.  相似文献   
125.
Two kinds of FeIFN-alpha consisting of 166 amino acids (aa) and 171 aa were expressed in Escherichia coli, and the purified proteins were tested for antiviral activity on homologous and heterologous animal cells. Crude FeIFN induced in feline cells revealed antiviral activity on both homologous and heterologous animal cells. In contrast, both types of recombinant FeIFN-alpha revealed antiviral activity only on the feline cells. All of the FeIFN-alpha subtypes showed high activity to vesicular stomatitis virus, and the three species of feline viruses belonging to different families.  相似文献   
126.
Between the laminar epidermis and the laminar dermis of laminar region (LR) in equine foot, it can be observed the basement membrane zone (BMZ), which is composed of a basement membrane and its accompaniments like the hemidesmosome and anchoring fibril. Alteration in the BMZ in equine laminitis is possibly related with not only development but also recovery outcome and recurrence of this disease. However, there is little known about the structure of the BMZ during the recovery phase of this disease. To assess the condition of the BMZ of LR affected by chronic laminitis, the tissue was examined in three cases at two weeks, four weeks and three months after the onset of laminitis, using pathological, immunohistochemical and electron microscopic techniques. Histologically in all laminitis cases, there was a regenerated laminar epidermis with proliferating keratinocytes between the Stratum medium and the dermis, but it included the undeveloped secondary epidermal laminae (ud-SELs) structure in one side of the primary epidermal laminae, especially in the part of the deep area of LR. Immunohistochemical results were positive for the anti-type IV collagen, anti-type VII collagen and anti-laminin 5 antibodies in the most BMZs. However, partial BMZs adjacent to the ud-SELs were negative for the anti-type VII collagen and anti-laminin 5 antibodies. Ultrastructurally, in the BMZ of the ud-SEL, the lamina densa and the lamina lucida were present. In contrast, the anchoring fibrils and the hemidesmosomes were either absent, or present at lower than normal levels. In conclusion, the present study indicated that the part of regenerated LR in chronic laminitis was not able to fully restore to construct the BMZ for a long time, especially in the unilateral side of laminar epidermis. It might be related with recurrence of this disease.  相似文献   
127.
Plasma metabolites and immunoreactive insulin (IRI) concentrations and enzyme activities of some types of peripheral leucocytes were measured to clarify one aspect of the differences in nutrient metabolism between dogs and cats. There were no significant differences in plasma concentrations of glucose, triglyceride, free fatty acids and IRI between dogs and cats. Higher total cholesterol and lower HDL cholesterol concentrations were observed in feline plasma, and H/T ratio (HDL/total cholesterol concentrations) was significantly lower than that in canine plasma. The cytosolic activities of fructokinase (FK), pyruvate kinase (PK), glucose-6-phosphate dehydrogenase (G6PD) and lactate dehydrogenase (LDH) were significantly higher and the activities of cytosolic malate dehydrogenase (MDH) and mitochondrial glutamate dehydrogenase (GLDH) were significantly lower in feline leucocytes than those in canine leucocytes. Higher activities of FK, PK and G6PD, which regulate the rate of biosynthesis of fatty acids, may reflect the different characteristics in nutrient metabolism in feline tissues from canine tissues.  相似文献   
128.
The activities of the enzymes in the malate-aspartate shuttle were measured in peripheral leucocytes of spontaneous type 1 diabetic dogs and cats treated with insulin injections. In the diabetic dogs and cats, fasting plasma glucose concentrations were three- or fourfold greater than the control levels in spite of insulin injections and the activities of cytosolic malate dehydrogenase (MDH), one of pivotal enzymes in the malate-aspartate shuttle, were remarkably lower than the controls. Depressed expression of cytosolic MDH mRNA was confirmed by RT-PCR analysis in the diabetic animals. The cytosolic ratio of MDH/lactate dehydrogenase (LDH) activity (M / L ratio) in leucocytes of the diabetic animals was significantly lower than that of normal control animals. The smaller M / L ratio appeared to reflect depression of energy metabolism in the diabetic animals. Intrinsically lower and further decreased MDH activities may be factors that induce insulin resistance observed in diabetic cats.  相似文献   
129.
Vaccine trials were undertaken to determine whether the Fel-O-Vax FIV, a commercial dual-subtype (subtypes A and D) feline immunodeficiency virus (FIV) vaccine, is effective against a subtype B FIV isolate. Current results demonstrate the Fel-O-Vax FIV to be effective against a subtype B virus, a subtype reported to be the most common in the USA.  相似文献   
130.
BACKGROUND: Serodiagnosis of feline immunodeficiency virus (FIV) is complicated by the use of a formalin-inactivated whole-virus FIV vaccine. Cats respond to immunization with antibodies indistinguishable from those produced during natural infection by currently available diagnostic tests, which are unable to distinguish cats that are vaccinated against FIV, infected with FIV, or both. HYPOTHESIS: An enzyme-linked immunosorbent assay (ELISA) detecting antibodies against formalin-treated FIV whole virus and untreated transmembrane peptide will distinguish uninfected from infected cats, regardless of vaccination status. ANIMALS: Blood samples were evaluated from uninfected unvaccinated cats (n = 73 samples), uninfected FIV-vaccinated cats (n = 89), and FIV-infected cats (n = 102, including 3 from cats that were also vaccinated). METHODS: The true status of each sample was determined by virus isolation. Plasma samples were tested for FIV antibodies by a commercial FIV diagnostic assay and an experimental discriminant ELISA. RESULTS: All samples from uninfected cats were correctly identified by the discriminant ELISA (specificity 100%). Of the samples collected from FIV-infected cats, 99 were correctly identified as FIV-infected (sensitivity 97.1%). CONCLUSIONS AND CLINICAL IMPORTANCE: With the exception of viral isolation, the discriminant ELISA is the most reliable assay for diagnosis of FIV. A practical strategy for the diagnosis of FIV infection would be to use existing commercial FIV antibody assays as screening tests. Negative results with commercial assays are highly reliable predictors for lack of infection. Positive results can be confirmed with the discriminant ELISA. If the discriminant ELISA is negative, the cat is probably vaccinated against FIV but not infected. Positive results are likely to represent infection.  相似文献   
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