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1.
The question of the roles of the two main parts of the insect brain, the mushroom bodies and the central complex, in controlling motor coordination and triggering a variety of behavioral programs, including sound production, remains controversial. With the aim of improving our understanding of this question, we studied the parameters of songs used by five-day-old males during courtship for fertilized wild-type females (Canton-S, C-S) over 5-min periods at 25°C; males were of two wild-type Drosophila Melanogaster lines (Berlin and C-S). Berlin males lacking mushroom bodies because of treatment with hydroxyurea during development (chemical removal of the mushroom bodies) were used, along with two mutants with defects in the mushroom bodies (mbm 1 and mud 1), two mutants with defects in the central complex (ccb KS127 and cex KS181), and mutant cxb N71 with defects in both the mushroom bodies and the central complex. The experiments reported here showed that courtship songs in males lacking mushroom bodies were virtually identical to those of wild-type males. The main parameters of pulsatile song in mutants mbm 1 and mud 1 (interpulse interval and train duration) were insignificantly different from those of the songs of wild-type flies, though the stability of the pulse oscillator was the same. Flies of these lines were no different from wild-type flies in terms of courtship success (percentage of copulating pairs in 10-min tests). Conversely, the songs of mutants with defects in the central complex differed from those of wild-type males. Firstly, there was degradation of the stability of the pulse oscillator and interpulse intervals were very variable. In addition, pulses were often significantly longer and appeared multicyclic, as in the well-known cacophony mutant, while the mean train duration was significantly shorter. Males of the line cex KS181 usually courted very intensely, though abnormal sounds were generally emitted. Mutants cex KS181 and ccb KS127 were significantly less successful in courtship than wild-type flies. These data show that the central complex appears to play a very important role in controlling song, while the mushroom bodies are not related to this function.  相似文献   
2.
We previously reported that two-third of workers in a Bunashimeji mushroom (Hypsizigus marmoreus) farm complained of respiratory allergic symptoms, but one-third workers did not suffer from such symptoms even when working for a long period. CD4+ T-helper (Th) cells increased, and Th2/Th1 ratio increased in the allergic workers. To address these immunological backgrounds, we have investigated whether there is any relationship between mushroom allergy and human leukocyte antigen (HLA) class II alleles of DPB1, DQA1, DQB1, and DRB1 by using the polymerase chain reaction-restriction fragment length polymorphism (RFLP) and sequencing-based typing methods. We observed that the allele frequencies of DQA1*0103, DQB1*0601, and DRB1*0803 were significantly higher in the workers having no allergic symptoms than allergic workers (DQA1*0103: 57 vs 25%, DQB1*0601: 49 vs 14%, and DRB1*0803: 29 vs 0%). However, this phenomenon was not seen in workers producing another kind of mushroom, Honshimeji (Lyophyllum aggregatum). The HLA-DRB1*0803 allele alone, the DRB1*0803, DQA1*0103, DQB1*0601 haplotype, or both were negatively associated with allergy to Bunashimeji, and these alleles might be involved in the prevention of Bunashimeji mushroom-specific respiratory allergy.  相似文献   
3.
Rice bran exhibits chemopreventive properties that may help to prevent colorectal cancer (CRC), and a short-term rice bran dietary intervention may promote intestinal health via modification of the intestinal microbiota. We conducted a pilot, double-blind, randomised placebo-controlled trial to assess the feasibility of implementing a long-term (24-week) rice bran dietary intervention in Chinese subjects with a high risk of CRC, and to examine its effects on the composition of their intestinal microbiota. Forty subjects were randomised into the intervention group (n = 19) or the control group (n = 20). The intervention participants consumed 30 g of rice bran over 24-h intervals for 24 weeks, whilst the control participants consumed 30 g of rice powder on the same schedule. High rates of retention (97.5%) and compliance (≥91.3%) were observed. No adverse effects were reported. The intervention significantly enhanced the intestinal abundance of Firmicutes and Lactobacillus, and tended to increase the Firmicutes/Bacteroidetes ratio and the intestinal abundance of Prevotella_9 and the health-promoting Lactobacillales and Bifidobacteria, but had no effect on bacterial diversity. Overall, a 24-week rice bran dietary intervention was feasible, and may increase intestinal health by inducing health-promoting modification of the intestinal microbiota. Further larger-scale studies involving a longer intervention duration and multiple follow-up outcome assessments are recommended.  相似文献   
4.
目的 建立麸炒白术Atractylodis Macrocephalae Rhizoma炮制全过程的定性判别模型,筛选出可以表征麸炒白术不同炮制程度的气味成分。方法 制备麸炒白术饮片,不同时间点取样进行分析。采用Heracles NEO超快速气相电子鼻采集气味图谱,与Arochembase数据库对比得到气味成分信息,结合峰面积分析气味成分的变化规律并进行化学计量学分析。结果 通过判别因子分析(discriminant factor analysis,DFA)、正交偏最小二乘-判别分析(orthogonal partial least squaresdiscriminant analysis,OPLS-DA)、层次聚类分析(hierarchical cluster analysis,HCA)等将麸炒白术炮制全过程样品成功分为4类:生品、炮制不及、炮制成品和炮制太过。在炮制过程中,3-甲基十五烷、十二烷基丙酸酯、正辛基环己烷、1,3-二硝基苯、8-甲基十五烷5个气味成分的峰面积占比较高,其中1,3-二硝基苯在炮制全过程中峰面积呈降低趋势;3-甲基十五烷从炮制不及到炮制成品的过程中峰面积呈增加...  相似文献   
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6.
Medicinal mushrooms in recent years have been the subject of many experiments searching for anticancer properties. We previously screened thirteen mushrooms for their potential in inhibiting tumor growth, and found that the water extract of Amauroderma rude exerted the highest activity. Previous studies have shown that the polysaccharides contained in the water extract were responsible for the anticancer properties. This study was designed to explore the potential effects of the polysaccharides on immune regulation and tumor growth. Using the crude Amauroderma rude extract, in vitro experiments showed that the capacities of spleen lymphocytes, macrophages, and natural killer cells were all increased. In vivo experiments showed that the extract increased macrophage metabolism, lymphocyte proliferation, and antibody production. In addition, the partially purified product stimulated the secretion of cytokines in vitro, and in vivo. Overall, the extract decreased tumor growth rates. Lastly, the active compound was purified and identified as polysaccharide F212. Most importantly, the purified polysaccharide had the highest activity in increasing lymphocyte proliferation. In summary, this molecule may serve as a lead compound for drug development.  相似文献   
7.
This study was the first to detect the presence of the two compounds momilactone A (MA) and momilactone B (MB) in rice bran using liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). By in vitro assays, both MA and MB exhibited potent inhibitory activities on pancreatic α-amylase and α-glucosidase which were significantly higher than γ-oryzanol, a well-known diabetes inhibitor. Remarkably, MA and MB indicated an effective inhibition on trypsin with the IC50 values of 921.55 and 884.03 µg/mL, respectively. By high-performance liquid chromatography (HPLC), quantities of MA (6.65 µg/g dry weight) and MB (6.24 µg/g dry weight) in rice bran were determined. Findings of this study revealed the α-amylase, α-glucosidase and trypsin inhibitors MA and MB contributed an active role to the diabetes inhibitory potential of rice bran.  相似文献   
8.
The analysis of phytates in extrudates containing rye bran was done by a colorimetric method with the Wade reagent. The changes in profiles of myo-inositol phosphates indicate that, although no isomers with positive physiological functions (such as I(1,4,5)P3, I(1,2,3)P3 or I(1,3,4,5)P4) were formed, the beneficial impact of extrusion is the reduction of phytates, as compared to the raw material. The obtained snacks containing rye bran received acceptable to desirable sensory scores.  相似文献   
9.
Agaricus sylvaticus mushroom has been widely studied because of its high nutritional value and medicinal properties. The objective of this study was to evaluate the antioxidant potential of both alcoholic and aqueous extracts of Agaricus sylvaticus and quantify their total polyphenol content. The antioxidant activity was performed by the 2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity and total polyphenol content was assessed by colorimetric method. Observation also noted the great antioxidant potential of aqueous, alcoholic and ethereal extracts (14.6%, 75.6% and 14.6%, respectively) of the Agaricus sylvaticus mushroom, highlighting the alcoholic extract, which demonstrates the extraordinary benefits of this mushroom in the diet, since antioxidants prevent premature ageing and various types of cancer.  相似文献   
10.
A new isoprenylated sanggenon-type flavanone, nigrasin K (1), together with three known analogs (24) and five known Diels–Alder adducts (59), were isolated from the twigs of Morus nigra. Their structures were elucidated by spectroscopic methods. Sanggenon M (2), chalcomoracin (5), sorocein H (6), kuwanon J (7), sanggenon C (8), and sanggenon O (9) showed significant inhibitory effects on mushroom tyrosinase.  相似文献   
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