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51.
Discovery of Helicobacter (H.) pylori has led to a fundamental change in our understanding of gastric diseases in humans. Previous studies have found various Helicobacter spp. in dogs and cats, and pets have been questioned as a zoonotic carrier. The present study surveyed the Helicobacter infections and investigated the presence of H. felis and H. pylori infections in domestic and feral cats in Korea. Sixty-four domestic cats and 101 feral cats were selected from an animal shelter. Saliva and feces were evaluated by Helicobacter genus-specific polymerase chain reaction (PCR). Genus-specific PCR positive samples were further evaluated for H. felis and H. pylori using specific primer pairs. Thirty-six of 64 (56.3%) samples from domestic cats and 92 of 101 (91.1%) samples from feral cats were PCR positive; the positive rate of feces samples was higher than that of saliva samples in both groups. H. felis and H. pylori species-specific PCR was uniformly negative. The prevalence of Helicobacter spp. in feral cats was approximately two-fold higher than that of domestic cats. The fecal-oral route may be more a common transmission route not only between cats but also in humans.  相似文献   
52.
Pharmacological inhibition of acyl CoA:diacylglycerol acyltransferase (DGAT, EC 2.3.1.20) has emerged as a potential therapy for the treatment of obesity and type 2 diabetes. Bioassay-guided isolation of CHCl3 extracts of the fruits of Piper longum and Piper nigum (Piperaceae), using an in vitro DGAT inhibitory assay, lead to isolation of a new alkamide named (2E,4Z,8E)-N-[9-(3,4-methylenedioxyphenyl)-2,4,8-nonatrienoyl]piperidine (2), together with four known alkamides: retrofractamide C (1), pipernonaline (3), piperrolein B (4), and dehydropipernonaline (5). Compounds 2-5 inhibited DGAT with IC50 values of 29.8 (2), 37.2 (3), 20.1 (4), and 21.2 (5) microM, respectively, but the IC50 value for 1 was more than 900 microM. This finding indicates that compounds possessing piperidine groups (2-5) can be potential DGAT inhibitors.  相似文献   
53.
An experimental study was performed to determine the feasibility of usingorganobentonite modified with quarternary ammonium cations (QACs) as a reactive medium in immobilization and biodegradation barriers for mixed contaminants in the subsurface soil. Various factors, including interactions between heavy metals, organic contaminants, and soil microorganisms, were investigated when they coexisted with untreated bentonite and organobentonite. Batch sorption tests for cadmium and lead were conducted to quantify sorption selectivity of these metals on untreated bentonite and organobentonite. Metal concentrations of 50 × 10-6 M slightly reduced the growth of soil microbes and partially interfered with the biodegradation of phenol. Soil microorganisms tested with untreated bentonite grew after approximately 25 hr of lag period and degraded phenol completely within 350 hr. The results from this study demonstrate that organobentonite could be used as a reactive medium for immobilization and biodegradation of organic contaminants in the presence of heavy metals in the subsurface soil.  相似文献   
54.
Structured lipids (SLs) for formulating trans-free margarines were synthesized by lipase-catalyzed interesterification of the blends of canola oil (CO), palm stearin (PS), and palm kernel oil (PKO) in weight ratios (CO/PS/PKO) of 40:60:0, 40:50:10, 40:40:20, 40:30:30, 50:30:20, and 60:25:15. The atherogenicity was determined using fatty acid profiles. We also determined the physical properties (melting/crystallization profiles, solid fat content, polymorphism, and microstructure) of SLs and the textural properties of margarines made with the SLs. The SLs from the 50:30:20 and 60:25:15 blends had atherogenic indices similar to or lower than those of the commercial trans (CTMF) and similar to the trans-free margarine fats (CTFMF). SLs from the blends with PKO contained a wide range of fatty acids (C6-C20) and had more beta' than beta polymorphs. Margarines made with SLs from 50:30:20 and 60:25:15 blends possessed similar hardness, adhesiveness, or cohesiveness to margarines made with CTMF and CTFMF, respectively. Therefore, CO/PS/PKO-based SLs were suitable for formulating trans-free margarines with low atherogenicity and desirable textural properties.  相似文献   
55.
The protective effect of c9,t11-conjugated linoleic acid (CLA) on the inhibition of gap junctional intercellular communication (GJIC) was examined in a human mammary epithelial cell line (MCF-10A) treated with 12-O-tetradecanoylphorbol-13-acetate (TPA), relative to t10,c12-CLA isomer. TPA inhibited GJIC in a dose-dependent and reversible manner and was associated with connexin 43 phosphorylation. Pretreatment of 20 μM c9,t11-CLA for 24 h prior to 60 nM TPA for 1 h prevented the inhibition of GJIC by reducing the phosphorylation of connexin 43 via suppressing extracellular signal-regulated kinases (ERK1/2) activation. Reactive oxygen species (ROS) accumulation by TPA was attenuated by c9,t11-CLA. The efficacy of c9,t11-CLA in protecting inhibition of GJIC, connexin 43 phosphorylation, and ROS production was superior to that of t10,c12-CLA. These results suggest that c9,t11-CLA, including t10,c12-CLA, prevents the carcinogenesis of MCF-10A cells by protecting down-regulation of GJIC during the cancer promotion stage, and lack of their toxicities could be an excellent indicator for the chemoprevention of breast cancer.  相似文献   
56.
Characteristic aroma components of water dropwort (Oenanthe javanica DC.) were evaluated by aroma extract dilution analysis and solid-phase microextraction-gas chromatography-olfactometry. Alpha-Terpinolene (plastic/cucumber-like) was the most intense aroma-active compound in water dropwort. Other potent aroma-active compounds included p-cymene (kerosene-like), alpha-terpinene (lemon), (E)-caryophyllene (woody), (Z,E)-alpha-farnesene (woody), hexanal (green), (Z)-3-hexenol (green), phenylacetaldehyde (honey), (E)-2-nonenal (cucumber), bornyl acetate (cooked vegetable), and gamma-terpinene (lemon). Of these, p-cymene was believed to be primarily responsible for the distinct kerosene-like aroma note of water dropwort. The aroma property of p-cymene was dependent on its concentration and was described as kerosene-like at relatively high concentrations but changed to citrus and green aroma notes at low concentrations.  相似文献   
57.
Ozone effects on Mediterranean forests were studied for 10 years in southern France. The aim of these studies was to understand the impact of the pollutant on foliar damage among Aleppo pine (Pinus halepensis Mill) and Arolla pine (Pinus cembra L) populations. During the summers of 2001 and 2002, ozone concentrations were measured using UV absorption analysers (4) and passive samplers (29) at two forest monitoring sites: Site 1 in the Nice coastal area for Aleppo pine and Site 2 in the Mercantour mountains for Arolla pine, in the vicinity of tree observation sites. AOT 40 values were quite high (25–33 ppm.h), especially in the Mercantour mountains, for the 5 months of measurement. Foliar damage (defoliation and discoloration) and specific symptoms (chlorotic mottle) were observed on 8 Aleppo pine and 13 Arolla pine plots. For Arolla pines, there was a significant correlation between defoliation and chlorotic mottles. There was also a correlation between mean ozone concentrations measured by passive samplers and chlorotic mottles. These correlations were less significant for Aleppo pine.  相似文献   
58.
The objective of this study was to develop equations for estimating ileal digestible crude protein (CP) and metabolizable energy (ME) contents of meat meal (MM) and meat and bone meal (MBM) as feed ingredients for pigs based on in vitro assays. Test ingredients were 4 sources of MM and 3 sources of MBM. Ash and CP contents of the ingredients ranged from 3.8% to 33.1% and 46.8% to 82.9% (as-is basis), respectively. In vitro ileal disappearance (IVID) of CP was determined and ileal digestible CP content was calculated by multiplying CP content by IVID of CP. In vitro total tract disappearance (IVTTD) of dry matter (DM) was determined and ME was calculated using gross energy, CP contents, and IVTTD of DM. The IVID of CP and IVTTD of DM ranged from 77.2% to 88.7% and from 82.7% to 92.4%, respectively. Calculated ileal digestible CP and ME contents ranged from 37.8% to 73.5% DM and 2,405 to 3,905 kcal/kg DM, respectively. Ash contents were negatively correlated (P < 0.001) with CP (r = −0.99), in vitro ileal digestible CP (r = −0.97), gross energy (r = −1.00), in vitro digestible energy (r = −0.97), and adjusted ME (r = −0.97). The most fitting equations for ileal digestible CP and adjusted ME were: ileal digestible CP (% DM) = 11.91 − 0.90 × Ash (% DM) + 0.74 × IVID of CP (%) (R2 = 0.99) and adjusted ME (kcal/kg DM) = 130.85 − 50.90 × ash (% DM) + 47.06 × IVTTD of DM (%) (R2 = 0.99). To validate the accuracy of the prediction equations for ME, mean bias and linear bias were determined using a regression analysis. Calculated ME values of MM and MBM were in a good agreement with data obtained from animal experiments based on a statistically insignificant bias in the models. In conclusion, ME concentrations of MM and MBM as swine feed ingredients can be calculated using ash concentration and in vitro disappearance of dry matter.  相似文献   
59.
BackgroundDiseases related to cerebrospinal fluid flow, such as hydrocephalus, syringomyelia, and Chiari malformation, are often found in small dogs. Although studies in human medicine have revealed a correlation with cerebrospinal fluid flow in these diseases by magnetic resonance imaging, there is little information and no standard data for normal dogs.ObjectivesThe purpose of this study was to obtain cerebrospinal fluid flow velocity data from the cerebral aqueduct and subarachnoid space at the foramen magnum in healthy beagle dogs.MethodsSix healthy beagle dogs were used in this experimental study. The dogs underwent phase-contrast and time-spatial labeling inversion pulse magnetic resonance imaging. Flow rate variations in the cerebrospinal fluid were observed using sagittal time-spatial labeling inversion pulse images. The pattern and velocity of cerebrospinal fluid flow were assessed using phase-contrast magnetic resonance imaging within the subarachnoid space at the foramen magnum level and the cerebral aqueduct.ResultsIn the ventral aspect of the subarachnoid space and cerebral aqueduct, the cerebrospinal fluid was characterized by a bidirectional flow throughout the cardiac cycle. The mean ± SD peak velocities through the ventral and dorsal aspects of the subarachnoid space and the cerebral aqueduct were 1.39 ± 0.13, 0.32 ± 0.12, and 0.76 ± 0.43 cm/s, respectively.ConclusionsNoninvasive visualization of cerebrospinal fluid flow movement with magnetic resonance imaging was feasible, and a reference dataset of cerebrospinal fluid flow peak velocities was obtained through the cervical subarachnoid space and cerebral aqueduct in healthy dogs.  相似文献   
60.
Thirty-four dogs with no deep pain perception due to acute thoracolumbar intervertebral disc disease underwent decompression surgery within 1 week of diagnosis. All dogs underwent hemilaminectomy. Adipose derived mesenchymal stem cells (AD-MSCs) were transplanted into the injured spinal cord parenchyma for the AD-MSCs transplant dogs. Long-term outcome was evaluated at the end of the follow-up period (> 6 months). AD-MSCs combination treatment showed better recovery outcomes compared to decompression surgery alone. These results indicate that this stem cell therapy is a potential therapeutic strategy to overcome the limitations of treatment for spinal cord injury in clinical medicine.  相似文献   
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