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1.
The pathological effects of copper deficiency (COD) are well known. However, the pathogenesis of cardiomyopathy resulting from COD remains unclear. In this study, aimed to elucidate the pathogenesis of COD-induced cardiomyopathy by examining the morphology of the cardiovascular system in copper-deficient rats using histopathology, immunohistochemistry, and scanning and transmission electron microscopy. Changes detected in the myocardium and interstitium were consistent with those reported for COD. Morphological changes included mesh-like changes in the capillary endothelial cells that appear to be a novel finding in COD-induced cardiomyopathy. These changes are hypothesized to result from abnormal vascular remodeling following damage to the basement membrane and due to the mechanical effects of myocardial contractions. Although cardiomyopathy may be associated with microcirculatory disorders arising from these lesions, further investigations are necessary to demonstrate a causal relationship between the pathogenesis of cardiomyopathy and the contribution of these lesions to disease progression.  相似文献   
2.
Ferret polymorphonuclear cells (PMNs) and peripheral blood mononuclear cells (PBMCs) were separated from whole blood by density gradient centrifugation. Using a 50% Percoll solution (density=1.066), PMNs and PBMCs were successfully isolated after centrifugation; the purities of the PMNs and PBMCs were 94.2% and 95.6%, respectively. To evaluate the function of isolated ferret PMNs, we measured the superoxide generation with a MCLA-dependent chemiluminescence assay. The isolated ferret PMNs responded to phorbol 12-myristate 13-acetate (PMA) with kinetics similar to that of human PMNs. The ferret PMNs did not respond to N-formyl-Met-Leu-Phe (fMLF), unlike human PMNs, which rapidly responded. Thus, authors established a method for the rapid separation of highly purified populations of functional PMNs from the whole blood of ferrets.  相似文献   
3.
The incidence of canine rabies has been widely reported in Brazil, and new rabies virus (RV) variants, genetically similar to canine RV, have recently been isolated from foxes. In order to derive the epidemiological characteristics of Brazilian Carnivora RV, Brazilian RVs isolated from dogs, cats, and foxes were genetically analyzed. Brazilian Carnivora RV isolates were divided into 2 main lineages. The predominant lineage was found in dogs and cats, which included the Argentinean and Bolivian Carnivora RV isolates, and was extensively distributed throughout Brazil and surrounding countries. The other lineage consisted of three sublineages containing Brazilian dog and fox RV isolates, with the dog sublineages located on an internal branch of 2 fox sublineages, suggesting that RV transmission events might have occurred between foxes and dogs in the past. These results suggest that contact between dogs and wildlife has the potential to generate new rabies variants and that it is important to control RV infection cycles in both dogs and wildlife to prevent spread of rabies infection.  相似文献   
4.
In most literature on soil, the term humus has been used as synonymous with soil organic matter, on the other hand, it has been applied to a portion of soil organic matter that has decomposed and has lost the structure of the original matter, from which it has derived. Scheffer and Schachtschabel 1) defined the humus not synonymously with soil organic matter, but, in a broad sense, as all the dead organic substances which are accumulated on the soil surface as well as in the soil layer, and undergo continually decomposition, alteration, and synthetic reactions. According to them, the composition groups of humus are divided into non-humic and humic, and the latter group is sub-divided into (1) fulvic acid and humo-lignin acid, (2) humic acid, (3) humin, and (4) humus coal. Some natures of these composition groups of humus are shown in Table 1.  相似文献   
5.
A pot experiment was conducted to investigate the influences of indigenous phototrophs on methane (CH4) emissions from a paddy soil where rice straw was incorporated or was surface-applied. During the cultivation, half of the pots were covered with aluminum foil, except for the minimum space for rice plants, to prevent ambient light reaching the floodwater or the soil surface. Growth of oxygen-producing phototrophs was hardly observed in the unilluminated plots, whereas intensive growth of algae, duckweed and hydrophytes was found in the illuminated ones. Plant growth was not affected by the different treatments. Seasonal changes in CH4 emission determined by a closed chamber method indicated that illumination had no or only minor effects on CH4 emissions when rice straw was incorporated or was not applied, but significantly reduced CH4 emissions when rice straw was surface-applied. Methanogenesis occurring in the soil-floodwater interface was further investigated in two lab-scale model experiments measuring methanogenic activity. As a result, more activated methanogenesis was found in the surface-applied rice straw and the soil around the straw compared with the soil incubated without rice straw. The magnitude of the methanogenic activity in the rice straw incubated under illuminated conditions was significantly lower than that incubated in the dark. Consequently, this study demonstrates that methanogenesis in paddy soil occurs even in the soil-floodwater interface if plant residues like rice straw exist, and such methanogenesis is likely to be suppressed by growth of indigenous phototrophs under illumination.  相似文献   
6.
Greenhouse-grown tree ripe (TR) and mature green (MG) mangoes (cv. Irwin) were exposed to high electric field treatment before 20 and 30 days of storage at 5 degrees C. MG fruits were allowed to ripen at room temperature after low-temperature storage. Fruit physical quality attributes, ascorbic acid, carotene, quercetin, total phenols, and antioxidant capacity were estimated before and after the storage period. Antioxidant capacity of fruit juice was estimated using the ferric reducing antioxidant power (FRAP) assay. Fruit firmness decreased significantly during storage. Titratable acidity decreased 20 days after storage. Total soluble solids did not change during storage. Antioxidant capacity of fruits remained unchanged up to 20 days of storage period and decreased thereafter. Total phenol and carotenes increased during storage. Antioxidant capacity of fruits was significantly correlated only to ascorbic acids. Peel color and carotenes were higher in TR fruits, whereas titratable acidity and firmness were higher in MG fruits. There was no significant difference in other parameters between the stages of picking. Electric field pretreatment affected the respiration and antioxidant capacity of TR fruits and did not have any significant affect on other parameters. TR mangoes of cv. Irwin are more suitable for low-temperature storage and can be successfully stored for up to 20 days at 5 degrees C without any significant losses in functional properties and quality attributes.  相似文献   
7.
Plant Foods for Human Nutrition - Adipose tissue is an endocrine organ and its endocrine function is closely associated with type 2 diabetes mellitus. Valeriana officinalis (Valerian) exerts some...  相似文献   
8.
Rhamnose-binding lectin (RBL) is one of the animal lectin categories which take part in the innate immune responses of fish. Osmerus lanceolatus lectin (OLL) from shishamo smelt eggs is an RBL composed of two tandem-repeated domains, both of which are considered to be a carbohydrate-recognition domain. SAL, catfish (Silurus asotus) egg RBL composed of three domains, binds to Burkitt’s lymphoma Raji cells through globotriaosylceramide (Gb3) carbohydrate chain and to reduce cell size and growth by altering membrane composition without causing cell death. In this experiment, we tried to compare the binding effects of these two RBLs on Raji cells. Flow cytometric and fluorescence microscopic analyses revealed that OLL also directly bound to and shrunk Raji cells with ten times less reactivity than SAL but reduced cell growth with decreasing cell viability. Anti-Gb3 antibody completely blocked the binding of SAL to Raji cells but not that of OLL. In addition, the direct bindings of OLL and SAL to Raji cells were comparably inhibited by melibiose, but lactose was more effective inhibitor for the binding of OLL than that of SAL. These results suggest that OLL has slightly different cell-binding property compared with SAL and binds not only to Gb3 but also to the other carbohydrate receptor-bearing β-galactoside chains. The quantitative RT-PCR analysis revealed that SAL induced the expression of TNF-α but not of IFN-γ, IL-1β, and IL-10. Thus, SAL-induced cytostatic effect on Raji cells might be partially caused by TNF-α-mediated signaling pathway.  相似文献   
9.
10.
OBJECTIVE: To determine characteristics of power spectral analysis of heart rate variability (HRV) during a 24-hour period in dogs and to evaluate the effects of vagal and sympathetic tone on HRV ANIMALS: 16 healthy adult Beagles. PROCEDURE: Power spectral analysis of HRV was conducted, using 24-hour ambulatory ECG recordings. Circadian rhythms were evaluated in terms of absolute units of low-frequency (LF) and high-frequency (HF) powers, their ratio (LF:HF), and their adjusted (normalized) units (LF[norm] and HF[norm]). Three or 4 dogs were used for simultaneous measurement of heart rate and respiratory waveform as well as to evaluate treatment (propranolol, atropine, or both) administered to cause blockade of the autonomic nervous system. RESULTS: Values for LF and HF powers, LF:HF, LF(norm), and HF(norm) had obvious rhythmicity in clinically normal dogs. The HF power of HRV in dogs was extremely high, compared with that of other species, and HF peaks corresponded to peaks obtained from respiratory waveforms. Blockade of the autonomic nervous system documented that HRV in dogs was mostly attributable to vagal activity. CONCLUSION AND CLINICAL RELEVANCE: We determined characteristics of power spectral analysis of HRV in dogs, including circadian rhythm of the autonomic nervous system. Power spectral analysis of HRV may provide a useful noninvasive technique for assessing the effect of drugs on activity of the autonomic nervous system in dogs.  相似文献   
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