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51.
52.
BackgroundSince 2013, the number of requests for diagnosis for horses based on neurological symptoms has increased rapidly in South Korea. The affected horses have commonly exhibited symptoms of acute seasonal hindlimb ataxia. A previous study from 2015–2016 identified Setaria digitata as the causative agent.ObjectivesThis study is an epidemiological investigation to find out risk factors related to the rapid increase in hindlimb ataxia of horses due to aberrant parasites in South Korea.MethodsAn epidemiological investigation was conducted on 155 cohabiting horses in 41 horse ranches where the disease occurred. The surrounding environment was investigated at the disease-causing horse ranches (n = 41) and 20, randomly selected, non-infected ranches.ResultsHindlimb ataxia was confirmed in nine cohabiting horses; this was presumed to be caused by ectopic parasitism. Environments that mosquitoes inhabit, such as paddy fields within 2 km and less than 0.5 km from a river, had the greatest association with disease occurrence.ConclusionsMost horse ranches in South Korea are situated in favorable environments for mosquitoes. Moreover, the number of mosquitoes in the country has increased since 2013 due to climate change. Additional research is required; however, these data show that it is necessary to establish guidelines for the use of anthelmintic agents based on local factors in South Korea and disinfection of the environment to prevent disease outbreaks.  相似文献   
53.
The establishment of pregnancy is a complex process that requires a well-coordinated interaction between the implanting conceptus and the maternal uterus. In pigs, the conceptus undergoes dramatic morphological and functional changes at the time of implantation and introduces various factors, including estrogens and cytokines,interleukin-1β2(IL1 B2), interferon-γ(IFNG), and IFN-δ(IFND), into the uterine lumen. In response to ovarian steroid hormones and conceptus-derived factors, the uterine endometrium becomes receptive to the implanting conceptus by changing its expression of cell adhesion molecules, secretory activity, and immune response. Conceptus-derived estrogens act as a signal for maternal recognition of pregnancy by changing the direction of prostaglandin(PG) F2αfrom the uterine vasculature to the uterine lumen. Estrogens also induce the expression of many endometrial genes,including genes related to growth factors, the synthesis and transport of PGs, and immunity. IL1 B2, a pro-inflammatory cytokine, is produced by the elongating conceptus. The direct effect of IL1 B2 on endometrial function is not fully understood. IL1 B activates the expression of endometrial genes, including the genes involved in IL1 B signaling and PG synthesis and transport. In addition, estrogen or IL1 B stimulates endometrial expression of IFN signaling molecules,suggesting that estrogen and IL1 B act cooperatively in priming the endometrial function of conceptus-produced IFNG and IFND that, in turn, modulate endometrial immune response during early pregnancy. This review addresses information about maternal-conceptus interactions with respect to endometrial gene expression in response to conceptus-derived factors, focusing on the roles of estrogen and IL1 B during early pregnancy in pigs.  相似文献   
54.
Choi EM  Hwang JK 《Fitoterapia》2002,73(7-8):629-637
Yam (Dioscorea batatas) mucopolysaccharide (YMP) was examined for the ability to induce secretory and cellular responses in murine peritoneal macrophages. When macrophages were treated with various doses (10-100 microg/ml) of YMP for 48 h, a significant cytotoxicity against B 16 cells was observed. YMP also increased the myeloperoxidase activity and the production of H(2)O(2), O(2)(-), nitric oxide (NO) and tumor necrosis factor (TNF-alpha). However, there was a little alteration on the production of IFN-gamma. These results indicate that reactive oxygen intermediates (ROI), reactive nitrogen intermediates (RNI) and TNF-alpha are likely major mediators of cytotoxic activity of YMP-treated macrophages.  相似文献   
55.
The road effect on small rodent population is investigated at 8 fragmented forest areas in the Baekdudaegan moun-tain range, South Korea in September 2001, We especially focused on the distribution and body condition of small rodents near the roads, Korean field mouse (Apodemus peninsulae) seems to be more sensitive to the existence of a road than striped field mouse (Apodemus agradus), Korean field mouse prefers interior forest area to around road. Striped field mouse is a habitat generalist and has wide distributional range around road, but Korean field mouse is forest-inhabiting species and their distribu-tion is limited in forest area. These results suggest the effect of road is different on each small rodent species and their habitat preferences.  相似文献   
56.
The effects of various buckwheat materials (buckwheat flour [BF], dietary fiber extract [DE], flavonoids extract [FE], and rutin‐enhanced flavonoids extract [REFE]) on starch digestibility and noodle‐making properties were evaluated. When FE and REFE were incorporated into noodles, the amount of rapidly digestible starch and the predicted glycemic index (pGI) were reduced. However, BF and DE did not significantly decrease the pGI value of noodles. When assessing noodle properties, hardness was increased with increasing content of buckwheat materials, whereas other texture parameters were not significantly affected by buckwheat addition. All noodles were similar in regard to water absorption and swelling index, but cooking loss was slightly increased in FE and REFE noodles. FE and REFE demonstrated higher flavonoid stability during noodle making and, additionally, were more effective at reducing starch digestibility than BF and DE. REFE, specifically, does not generate quercetin (the cause of a bitter taste), and, therefore, REFE was effective in suppressing the hydrolysis of starch in the noodles, lowering the pGI.  相似文献   
57.
Canine hyperadrenocorticism (HAC) is one of the most common causes of general osteopenia. In this study, quantitative computed tomography (QCT) was used to compare the bone mineral densities (BMD) between 39 normal dogs and 8 dogs with HAC (6 pituitary-dependent hyperadrenocorticism [PDH]; pituitary dependent hyperadrenocorticism, 2 adrenal hyperadrenocorticism [ADH]; adrenal dependent hyperadrenocorticism) diagnosed through hormonal assay. A computed tomogaraphy scan of the 12th thoracic to 7th lumbar vertebra was performed and the region of interest was drawn in each trabecular and cortical bone. Mean Hounsfield unit values were converted to equivalent BMD with bone-density phantom by linear regression analysis. The converted mean trabecular BMDs were significantly lower than those of normal dogs. ADH dogs showed significantly lower BMDs at cortical bone than normal dogs. Mean trabecular BMDs of dogs with PDH using QCT were significantly lower than those of normal dogs, and both mean trabecular and cortical BMDs in dogs with ADH were significantly lower than those of normal dogs. Taken together, these findings indicate that QCT is useful to assess BMD in dogs with HAC.  相似文献   
58.

Background

Metabolic profile was initially designed as a presymptomatic diagnostic aid based on statistical analyses of blood metabolites to provide an early warning of certain types of metabolic disorder. However, there is little metabolic profile data available about Korean Hanwoo cows. Therefore, this study aimed to determine the reference intervals of metabolic profile for Korean Hanwoo cows.

Methods

Healthy animals (2,205) were selected and divided into early (day 1 to 95), middle (day 96 to 190) and late (day 191 to 285) period according to their gestating period. Metabolic profile including total protein (TP), albumin (Alb), urea (UREA), glucose (Glu), total cholesterol (T-Cho), long-chain fatty acid (LCFA), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), creatinine (Crea), calcium (Ca), inorganic phosphorous (iP) and magnesium (Mg) were analyzed using a TBA-40FR automatic biochemical analyzer. The data of Korean Hanwoo cows were then compared to those of the Japanese Wagyu cows.

Results

Most of the data of the Korean Hanwoo cows were relatively higher than those of Japanese Wagyu cows, with the exception of Glu and GGT. This may indicate that the nutritional level of feed for the Korean Hanwoo cows was higher than that of the Japanese Wagyu cows because of the different feeding system. In particular, relatively higher levels of UREA and LCFA were observed in the Korean Hanwoo cows, and this may also contribute to the low reproduction efficiency.

Conclusions

These findings may provide some theoretical basis for understanding the reproductive and feeding situation of Korean Hanwoo cows.  相似文献   
59.
The antioxidant activity of three major polyamine conjugates, N,N'-dicoumaroyl-putrescine (DCP), N-p-coumaroyl-N'-feruloylputrescine (CFP), and N,N'-diferuloyl-putrescine (DFP) isolated from corn bran, and their related hydroxycinnamic acids, p-coumaric acid and ferulic acid, were evaluated by three antioxidant in vitro assay systems, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide and hydroxyl radicals generated by enzymatic and nonenzymatic reactions. Additionally, five phenolic compounds were evaluated for melanogenesis inhibitory activity using mushroom tyrosinase and B16 melanoma cells. Most of the phenolic compounds significantly scavenged DPPH, superoxide, and hydroxyl radicals in a dose-dependent manner. Particularly, DFP showed potent DPPH (IC50 = 38.46 microM) and superoxide (IC50 = 291.62 microM) radical scavenging activities, while DCP exhibited the strongest hydroxyl radical scavenging activity (IC50 = 120.55 microM). CFP also exerted moderate DPPH, superoxide, and hydroxyl radical scavenging activities. Meanwhile, DCP (IC50 = 181.73 microM) showed potent tyrosinase inhibitory activity toward l-tyrosine as the substrate, whereas DFP (IC50 = 733.64 microM) significantly inhibited melanin synthesis in B16 melanoma cells. These current results indicate that these three polyamine conjugates from corn bran may be useful potential sources of natural antioxidants and skin-whitening agents.  相似文献   
60.
Newcastle disease virus (NDV) causes significant economic losses to the poultry industry in Southeast Asia. In the present study, 12 field isolates of NDV were recovered from dead village chickens in Vietnam between 2007 and 2012, and were characterized. All the field isolates were classified as velogenic. Based on the sequence analysis of the F variable region, two distinct genetic groups (Vietnam genetic groups G1 and G2) were recognized. Phylogenetic analysis revealed that all the 12 field isolates fell into the class II genotype VII cluster. Ten of the field isolates, classified as Vietnam genetic group G1, were closely related to VIIh viruses that had been isolated from Indonesia, Malaysia, and Cambodia since the mid-2000s, while the other two field isolates, of Vietnam genetic group G2, clustered with VIId viruses, which were predominantly circulating in China and Far East Asia. Our results indicate that genotype VII viruses, especially VIIh viruses, are predominantly responsible for the recent epizootic of the disease in Vietnam.  相似文献   
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