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81.
The present study demonstrates the effects of different muscle types and chiller ageing periods on the chemical composition, meat quality parameters, sensory characteristics and volatile compounds of Karean native cattle beed. Longissimus dorsi (LD) and Semitendinosus (ST) muscles aged for 7 days and 28 days were used. Moisture, cooking loss, total collagen and Warner‐Bratzler shear force (WBSF) values for the ST were higher than the LD muscle regardless of ageing period (P < 0.05). The LD muscle had higher intramuscular fat (IMF) (P < 0.05). Ageing for 28 days decreased WBSF values whereas it increased thiobarbituric acid of both muscles. Moreover, tenderness, juiciness and flavor scores were significantly higher for the LD muscle at both ageing periods. Increased ageing time improved tenderness of both muscles, and increased juiciness of the LD muscle, whereas there was decreased flavor score of ST muscle (P < 0.05). The majority of the volatile compounds formed from the oxidation of lipids showed differences between the two muscles. Ageing for 28 days increased in the amounts of many volatile compounds; however, the amounts of some important volatile compounds were decreased. These results clearly demonstrate that muscle type and ageing have a potential effect on meat quality, sensory characteristics and volatile profile.  相似文献   
82.
83.
Soybean leaves are eaten as seasonal edible greens in Korea. Analysis of the ethyl acetate extract of these leaves showed that it exhibited potent and selective neuraminidase inhibition, which began at the R3 stage and peaked at R7. Ten pterocarpans, including the new 6a-hydroxypterocarpan 10, were isolated from soybean leaves and their inhibition activities tested against a range of glycosidases. The relationship between structure and enzyme inhibition was investigated: 6a-hydroxypterocarpans exhibited much higher inhibition against neuraminidase (IC(50) = 2.4-89.4 μM) than α-glucosidase (IC(50) = 90.4-?>100 μM). Glyceollin VII (7) displayed 40-fold greater activity (IC(50) = 2.4 μM) against neuraminidase than α-glucosidase (IC(50) = 90.4 μM). On the other hand, coumestanes (1-3) were good α-glucosidase inhibitors (IC(50) = 6.0-42.6 μM). In kinetic analysis, the most potent neuraminidase inhibitors (5-10) were noncompetitive. HPLC analysis indicated that most pterocarpan synthesis began from the R3 stage, and a rapid change of pterocarpan concentrations was observed between the R4 and R7 stages.  相似文献   
84.
This study was carried out to investigate the changes of orexin-A (OXA) and neuropeptide Y (NPY) expression in the hypothalamus of the obese and lean Zucker Diabetic Fatty (ZDF) rats which have a missense mutation in the leptin receptor gene. The mean body weights (MBW) between the obese and lean ZDF rats were significantly different at 28 and 70 postnatal days. However, at 14 postnatal day, there was no significant difference in the MBW between the obese and lean ZDF rats in both male and female. The OXA immunoreactivities were not significantly different between the obese and lean ZDF rats in both sexes at 14, 28, and 70 postnatal days, respectively. The NPY immunoreactivity was higher in the obese than in the lean ZDF rats in both male and female at 28 and 70 postnatal days, whereas there was no significant difference between the obese and lean ZDF rats at 14 postnatal day. These results indicate that both OXA and NPY might halt their roles for food intake in the obese phenotype of the male and female ZDF rats in the preweaning period of 14 postnatal day, whereas NPY might play a main role in the obesity of these rats in the weaning period of 28 and 70 postnatal days.  相似文献   
85.
Theranostics is an integrated nanosystem that combines therapeutics with diagnostics in attempt to develop new personalized treatments with enhanced therapeutic efficacy and safety. As a promising therapeutic paradigm with cutting-edge technologies, theranostic agents are able to simultaneously deliver therapeutic drugs and diagnostic imaging agents and also monitor the response to therapy. Polymeric nanosystems have been intensively explored for biomedical applications to diagnose and treat various cancers. In recent years, glycol chitosan-based nanoagents have been developed as dual-purpose materials for simultaneous diagnosis and therapy. They have shown great potential in cancer therapies, such as chemotherapeutics and nucleic acid and photodynamic therapies. In this review, we summarize the recent progress and potential applications of glycol chitosan-based fluorescent theranostic nanoagents for cancer treatments and discuss their possible underlying mechanisms.  相似文献   
86.
ABSTRACT

Long-term fertilization tests evaluated rice (Oryza sativa) productivity in relation to application of nitrogen (N)-phosphorus (P)-potassium (K) (120-34.9-66.7 kg ha? 1, respectively) during 1967–1972 and N-P-K (150-43.7-83.3 kg ha? 1, respectively) during 1973–2000. The comparison treatments (NP, PK, and NK) and the control (not fertilized) were selected for calculating nutrient efficiency. Rice grain yield increased at a 17.78 kg ha? 1 yr? 1 in the control, mainly due to development of improved cultivars. Phosphorus management was found to be important for indigenous fertility and rice productivity in this paddy soil. Yield increased significantly with P fertilization. Without N fertilization (PK), rice productivity increased 56.85 kg ha? 1 yr? 1 from 62% of NPK at the initial stage to 74% after passing 34 years, which might be affected by increasing biological N fixation with P accumulation in soil. In NK treatment, rice yield increased at a relatively low rate (37.82 kg hr? 1 yr? 1) from the same rice productivity with that of NPK in 1967 to 91% after 34 years. In comparison, yield increased at a high rate (62.82 kg hr? 1 yr? 1) without K fertilization (NP) from ca. 90% of NPK and might exceed the yield of NPK after 64 years of long-term fertilization. Therefore, K fertilization level might be readjusted after long-term fertilizing in paddy soil.  相似文献   
87.

Background

Serotonin (5‐hydroxytryptamine, 5HT) is involved in hypothalamic regulation of energy consumption. Also, the gut microbiome can influence neuronal signaling to the brain through vagal afferent neurons. Therefore, serotonin concentrations in the central nervous system and the composition of the microbiota can be related to obesity.

Objective

To examine adipokine, and, serotonin concentrations, and the gut microbiota in lean dogs and dogs with experimentally induced obesity.

Animals

Fourteen healthy Beagle dogs were used in this study.

Methods

Seven Beagle dogs in the obese group were fed commercial food ad libitum, over a period of 6 months to increase their weight and seven Beagle dogs in lean group were fed a restricted amount of the same diet to maintain optimal body condition over a period of 6 months. Peripheral leptin, adiponectin, 5HT, and cerebrospinal fluid (CSF‐5HT) levels were measured by ELISA. Fecal samples were collected in lean and obese groups 6 months after obesity was induced. Targeted pyrosequencing of the 16S rRNA gene was performed using a Genome Sequencer FLX plus system.

Results

Leptin concentrations were higher in the obese group (1.98 ± 1.00) compared to those of the lean group (1.12 ± 0.07, P = .025). Adiponectin and 5‐hydroytryptamine of cerebrospinal fluid (CSF‐5HT) concentrations were higher in the lean group (27.1 ± 7.28) than in the obese group (14.4 ± 5.40, P = .018). Analysis of the microbiome revealed that the diversity of the microbial community was lower in the obese group. Microbes from the phylum Firmicutes (85%) were predominant group in the gut microbiota of lean dogs. However, bacteria from the phylum Proteobacteria (76%) were the predominant group in the gut microbiota of dogs in the obese group.

Conclusions and Clinical Importance

Decreased 5HT levels in obese group might increase the risk of obesity because of increased appetite. Microflora enriched with gram‐negative might be related with chronic inflammation status in obese dogs.  相似文献   
88.
The epidermal growth factor receptor (EGFR) kinase inhibitors gefitinib and erlotinib are effective treatments for lung cancers with EGFR activating mutations, but these tumors invariably develop drug resistance. Here, we describe a gefitinib-sensitive lung cancer cell line that developed resistance to gefitinib as a result of focal amplification of the MET proto-oncogene. inhibition of MET signaling in these cells restored their sensitivity to gefitinib. MET amplification was detected in 4 of 18 (22%) lung cancer specimens that had developed resistance to gefitinib or erlotinib. We find that amplification of MET causes gefitinib resistance by driving ERBB3 (HER3)-dependent activation of PI3K, a pathway thought to be specific to EGFR/ERBB family receptors. Thus, we propose that MET amplification may promote drug resistance in other ERBB-driven cancers as well.  相似文献   
89.
Melatonin affects diverse physiological functions through its receptor and plays an important role in the central nervous system. In the present study, we compared immunoreactivity patterns of arylalkylamine N-acetyltransferase (AANAT), an enzyme essential for melatonin synthesis, and melatonin receptor type 1B (MT2) in the spinal cord of young adult (2~3 years) and aged (10~12 years) beagle dogs using immunohistochemistry and Western blotting. AANAT-specific immunoreactivity was observed in the nuclei of spinal neurons, and was significantly increased in aged dog spinal neurons compared to young adult spinal neurons. MT2-specific immunoreactivity was found in the cytoplasm of spinal neurons, and was predominantly increased in the margin of the neuron cytoplasm in aged spinal cord compared to that in the young adult dogs. These increased levels of AANAT and MT2 immunoreactivity in aged spinal cord might be a feature of normal aging and associated with a feedback mechanism that compensates for decreased production of melatonin during aging.  相似文献   
90.
Fluorine was introduced into the 2-position of the side chain of abscisic acid (ABA) analogues by Wittig reaction of alpha-ionone derivatives with ethyl triethylphosphono-2-fluoroacetate. The effects of the fluorinated analogues were evaluated on inhibition of cress seed germination and inhibition of gibberellin-inducible alpha-amylase induction in embryoless barley half-seeds. (2E, 4E)-2-Fluoro-5-(1'-hydroxy-2',6', 6'-trimethyl-2'-cyclohexen-1'-yl)-3-methyl-2,4-pentadienoic acid (5b) showed potent inhibitory activity at the same level as ABA in the cress seed germination test, and 5b also inhibited gibberellin-inducible alpha-amylase induction at 4 x 10(-)(6), 3 times the concentration of ABA (1 x 10(-)(6)) for 50% inhibition of alpha-amylase production. 5b also showed dehydrin induction activity. These results indicate that fluorinated ABA analogues mimic ABA action and can be a lead for a plant growth regulator which regulates plant growth or protects plants from environmental stresses.  相似文献   
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