Pteridines in the fat body of a mutant of Drosophila melanogaster

A mutant, white-mottled orange, which deposits less than wild-type amounts of drosopterins in the eyes, has been found in Drosophila melanogaster. Variations in other pteridines were also observed. The mutant accumulates and later loses drosopterins in the abdominal fat body of adults.     

Long-lived chemiluminescence in cigarette smoke

Cigarette smooke contains high concentrations of unstable moleculles that react with oxygen to produce chemiluminescence. The chemiluminescent activity is concentrated in the aerosol phase that can be absorbed on glass-fiber filters and extracted into organic solvents. Cigarette smnoke in N, N-dimethylformamide produces a long-lasting luminescence visible to the dark-adapted eye. We have demonstrated the oxygen dependence and have measured the kinetics, activation energies, emission spectra, and absolute photon intensities of this chemiluminescence. The total light emission from a single puff (35 cubic centimeters) of cigarette smoke is greater than 10(12) photons. There was a significant correlation between smoke chemiluminescence anSd tar content. It is suggested that the chemical production of electronically excited states of aromatic hydrocarbons is equivalent to photoexcitation in the promotion of the carcinogenicity of these agents.     

Delta-9-tetrahydrocannabinol: localization in body fat

[(14)C]Delta(9)-Tetrahydrocannabinol (Delta(9)THC) was injected subcutaneously in rats every day for 1 to 26 days. Concentrations of Delta(9)THC and its metabolites, 11-hydroxytetrahydrocannabinol and 8,11-dihydroxytetrahydrocannabinol, were determined in various tissues. After a single injection, the concentration of Delta(9)THC in fat was ten times greater than in any other tissue examined, and persisted in this tissue for 2 weeks. With repeated injection, Delta(9)THC and its metabolites accumulated in fat and brain.     

Dopamine-mushroom body circuit regulates saliency-based decision-making in Drosophila

Drosophila melanogaster can make appropriate choices among alternative flight options on the basis of the relative salience of competing visual cues. We show that this choice behavior consists of early and late phases; the former requires activation of the dopaminergic system and mushroom bodies, whereas the latter is independent of these activities. Immunohistological analysis showed that mushroom bodies are densely innervated by dopaminergic axons. Thus, the circuit from the dopamine system to mushroom bodies is crucial for choice behavior in Drosophila.     

文昌鸡体脂分布及沉积规律的研究

为了解文昌鸡体脂分布及沉积规律,测定了27、53、79、105日龄以及育肥2、4、6、8周的文昌鸡腹脂率、皮下脂肪厚度、肌内脂肪含量及肝脏粗脂肪含量。结果表明,（1）文昌鸡脂肪在腹部、皮下和肌肉的沉积量随着日龄的增长而显著升高（P<0.05）;(2)胸肌肌内脂肪含量和腿肌肌内脂肪含量变化趋势一致,均在育肥6周时达到最大;（3）肝脏内粗脂肪含量呈波浪式变化,并在105日龄时达到最高值。     

Vitellogenic blood protein synthesis by insect fat body

The female fat body of a moth and a roach incorporated labeled amino acids in vitro into substances precipitable by antibodies formed in response to the sex-limited vitellogenic blood proteins of these species. The fat body of males failed to do so, as did that of females before the appearance of these proteins in the blood.     

The role of Drosophila mushroom body signaling in olfactory memory

The mushroom bodies of the Drosophila brain are important for olfactory learning and memory. To investigate the requirement for mushroom body signaling during the different phases of memory processing, we transiently inactivated neurotransmission through this region of the brain by expressing a temperature-sensitive allele of the shibire dynamin guanosine triphosphatase, which is required for synaptic transmission. Inactivation of mushroom body signaling through alpha/beta neurons during different phases of memory processing revealed a requirement for mushroom body signaling during memory retrieval, but not during acquisition or consolidation.     

RNA interference directs innate immunity against viruses in adult Drosophila

Innate immunity against bacterial and fungal pathogens is mediated by Toll and immune deficiency (Imd) pathways, but little is known about the antiviral response in Drosophila. Here, we demonstrate that an RNA interference pathway protects adult flies from infection by two evolutionarily diverse viruses. Our work also describes a molecular framework for the viral immunity, in which viral double-stranded RNA produced during infection acts as the pathogen trigger whereas Drosophila Dicer-2 and Argonaute-2 act as host sensor and effector, respectively. These findings establish a Drosophila model for studying the innate immunity against viruses in animals.     

Estimation of total body fat from potassium-40 content

A brief review is given of the development of methods for the determination of total body potassium by whole-body scintillation counting and of studies to establish the utility of body potassium as a measure of gross body composition including fat.     

Estimation of total body fat from potassium-40 content

On the assumption that the potassium content of the lean body mass is constant, it should be possible to estimate fat content in living man from a measurement of potassium-40 activity in the whole-body scintillation counter. A series of such measurements on children and young adults shows good correlations with skin-fold thickness and weight/height ratio as indices of fatness.     

昆虫脂肪体与抗药性的关系研究现状与分析

随着化学杀虫剂在农、林业生产和生活上广泛应用,在给害虫防治带来极大便利的同时,也对有利经济昆虫(如家蚕、蜜蜂等)、天敌昆虫的生存环境产生了极大的影响.同时,杀虫剂的大量使用也造成大量农林、卫生害虫抗药性的产生,使得农药的使用浓度越来越高,对环境产生巨大的压力,因此,昆虫的抗药性越来越成为多学科的研究热点.脂肪体是昆虫体内重要的物质存储和中间代谢组织,在昆虫对农药的代谢过程中发挥着重要的作用,研究昆虫脂肪体对农药的代谢机制,对于保护经济昆虫和防治农林害虫都具有重要意义.通过对昆虫脂肪体与昆虫抗药性的关系的研究现状进行综述,以了解昆虫脂肪体对有机磷农药及杀虫剂的代谢机制,为经济昆虫、天敌昆虫的保护及新型环境友好农药的研制奠定理论基础.     

Long-lived giant number fluctuations in a swarming granular nematic

Coherently moving flocks of birds, beasts, or bacteria are examples of living matter with spontaneous orientational order. How do these systems differ from thermal equilibrium systems with such liquid crystalline order? Working with a fluidized monolayer of macroscopic rods in the nematic liquid crystalline phase, we find giant number fluctuations consistent with a standard deviation growing linearly with the mean, in contrast to any situation where the central limit theorem applies. These fluctuations are long-lived, decaying only as a logarithmic function of time. This shows that flocking, coherent motion, and large-scale inhomogeneity can appear in a system in which particles do not communicate except by contact.     

ACOX3基因多态性对鸡体脂沉积的影响

文章通过分析酰基辅酶A氧化酶（Acyl-Coenzyme A Oxidases 3,ACOX3）基因单核苷酸多态性与鸡脂肪性状的关系,旨在了解该基因对鸡体脂沉积的影响。以东北农业大学高、低脂双向选择品系肉鸡为材料,采用PCR-RFLP方法检测ACOX3基因的多态性,并分析该基因多态性与鸡脂肪性状的关系。结果表明,ACOX3基因c.-228C>T突变位点在肉鸡高、低脂双向选择品系第10、11世代混合群体中,对腹脂重、腹脂率和血浆VLDL浓度有显著影响（P<0.05）;c.-442A>C突变位点在第8-11世代混合群体低脂系中,对腹脂重有显著影响（P<0.05）;c.27035A>G突变位点在第10、11世代混合群体低脂系中,对血浆VLDL浓度有显著影响（P<0.05）;c.16802C>T突变位点在第11世代低脂系中,对腹脂重、腹脂率有显著影响（P<0.05）。结果显示,ACOX3基因对鸡的体脂沉积有重要影响。ACOX3基因c.-228C>T突变位点对鸡脂肪性状有显著影响,可以尝试作为遗传标记对脂肪性状进行分子标记辅助选择。     

Insecticide content of diet and body fat of Alaskan natives

A study was made of the DDT and DDE content of the diet and body fat of native Alaskans who lived in isolated, primitive areas and had minimal contact with insecticides. No DDT or DDE was detected in any of the native Alaskan foods analyzed with the exception of two white owls, both of which contained low levels of DDE. Eskimos store considerably less DDT and DDE in their body fat than the general population in the United States. These low dietary levels and the resultant low levels in body fat are consistent with previously published data on the relationship between intake and storage of DDT.     

罗汉果甜苷V对持续光照小鼠脂肪积累的缓解作用

【目的】探究罗汉果甜苷V(MV)缓解持续光照导致小鼠脂肪积累的作用,为罗汉果在畜禽健康养殖中的应用提供参考依据。【方法】以15周龄雄性C57BL/6小鼠为研究对象,随机分为对照组(12 h光照∶12 h黑暗)、持续光照组(24 h光照)及持续光照添加MV处理组(每日灌胃100 mg/kg的MV),试验周期为5周。试验期间监测小鼠体质量和采食量,并检测其体脂率和能量代谢水平;试验结束后处死小鼠,采集腹股沟白色脂肪(iWAT)和附睾白色脂肪(e WAT)进行称重,通过苏木精—伊红(H-E)染色观察脂肪细胞形态学特征,并以实时荧光定量PCR检测脂肪组织中脂肪代谢及能量代谢相关基因的表达情况。【结果】在整个试验过程中,各处理组小鼠的体质量与采食量均无显著差异(P>0.05),但持续光照能导致小鼠体脂率极显著升高(P<0.01,下同),而氧气消耗量、二氧化碳排出量及产热量等基础代谢参数均极显著降低,iWAT和eWAT的百分比及细胞直径均极显著增大;iWAT和eWAT中的脂肪合成相关基因(Fabp4、Pparg2和Zfp423)相对表达量极显著上调,脂肪分解相关基因Lpl相对表达量极显著下调,能量代谢基因(Sirt1和Ppargc1a)相对表达量显著(P<0.05)或极显著下调,炎症反应相关基因Nfkb1相对表达量极显著上调。经MV处理后能使持续光照小鼠上述变化指标均恢复至正常水平,即MV能有效改善持续光照导致的小鼠能量代谢紊乱、缓解脂肪累积,以及缓解脂肪代谢、能量代谢及炎症反应相关基因的异常表达。【结论】持续光照会在不改变能量摄入的情况下导致机体脂肪积累,影响机体的正常代谢和健康。MV通过调控Sirt1、Ppargc1a等重要代谢相关基因表达,改善机体代谢紊乱,并通过促进脂肪分解和抑制脂肪合成相关基因表达,有效缓解持续光照导致的小鼠脂肪积累。