人参皂苷CK、淫羊藿苷对体外培养精子的剂量负荷试验

目的:项目拟通过观察在培养液中加入较高剂量的人参皂苷CK(Ginsenoside,G组)、淫羊藿苷(Icraiin,I组)两种药物前、后精子死亡率数据,评估两种药物单体在较大剂量时对体外精子的死亡率的影响。方法:新鲜液化的精液(semen)标本40份,F-10培养液调整浓度为1.0×107/m L,分别添加不同剂量的人参皂苷CK(Ginsenoside,Gin CK)、淫羊藿苷(Icraiin,Icr)按照不同药物浓度,G组分为500μg/m L组(G1组),100μg/m L组(G2组),I组分为500μg/m L(I1组),100μg/m L(I2组);设不添加任何物质的F-10组(F-10,F组)为阴性对照组,培养24 h后分别检查各组精子活动率和死亡率。结果:培养24 h后,精子死亡率从低到高分别是培养24 h后,I2组死亡率为41.31±17.49,F组死亡率为47.50±19.85,G2组死亡率为55.75±24.93,I3组死亡率为58.05±19.06,G1组死亡率为98.84±1.62。精子死亡率从低到高分别是I2组、F组、G2组、I1组、G1组,各组比较有差异(P0.05)。结论:较大剂量的Gin CK、Icr,均可引起体外培养的精子死亡率增高;在0.1 mg/m L的浓度下的Gin CK对精子的致死作用已经比较明显,而0.5 mg/m L对体外培养精子来说是致死剂量(98.84%),在0.1 mg/m L的剂量下的淫羊藿苷对精子的致死作用并不明显,在0.5 mg/m L剂量下Icr对精子致死作用有所提高,但远未达到Gin CK 98.4%的致死率。     

Comparative utility of hermetic and conventional grain storage bags for smallholder farmers: a meta-analysis

Postharvest management is critical to attaining household food, nutrition, and income security. Hermetic grain storage bags offer an effective pesticide-free way to protect stored grain against fungal and insect infestation. We evaluated articles indexed in the Web of Science that included experiments comparing the storage efficacy of conventional and hermetic storage bags based on grain germination rate, insect infestation, physical damage, mycotoxin contamination, and changes in weight and moisture content. Compared with grain stored in hermetic bags, grain stored in conventional bags lost 3.6-fold more seed viability, contained 42-fold more insects, had 11-fold more physical damage, and lost 23-fold more grain weight, while grain moisture levels were similar for both hermetic and conventional storage bags. Mycotoxin contamination levels were not as frequently assessed. Levels could be low in grain stored in both types of bags, or levels could be low in hermetic bags and significantly higher in conventional bags. The improved properties of grain stored in hermetic bags can increase food security and household income by providing safe storage options for maintaining seed germinability, and for consumption and/or sale when food supplies are high, or when prices are low. Hermetic bags are economically feasible for use by subsistence farmers in Sub-Saharan Africa for grain for household consumption and for carrying-over seed for planting in the next season. Additional studies are needed to verify the mycotoxin contamination results and to determine if there are differences in functional food characteristics, e.g. flavor and cooking properties, that have not been as comprehensively studied. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Great Lakes' contaminants reduce sperm production and fertilizing ability in mice

The long‐term effects of Great Lakes' contaminants on male reproductive performance resulting from lactational and dietary exposure were investigated. Female C57BL/6 J mice (F‐0) were mated with DBA/2 J male mice to produce B₆D₂‐F₁ offspring. Dams (F‐0) were fed one of three treatment diets during lactation. The three treatment diets were: (i) diet C, containing lab chow and fish oil; (ii) diet I, containing 60% Iowa carp and 40% lab chow; and (iii) diet G, containing 60% Great Lakes' carp and 40% lab chow. Diet C served as a lab‐chow control treatment, while diet I served as a fish‐diet control treatment. Diet G contained 2500 µg of polychlorinated biphenyls (PCBs) and 300 µg of 1,1‐dichloro‐2,2‐bis‐[p‐chlorophenyl]ethylene (4,4′‐DDE) per kilogram of feed. The offspring (F‐1) were continued on their respective maternal treatment diets from weaning until termination. Greater neonatal mortality and lesser body weights were observed in the F‐1 male mice on diet G. Lesser fecundity was observed in one‐year‐old F‐1 male mice on diet G following pairing with non‐treated female mice. The sperm concentration of F‐1 male mice on diet G was less than 30% of that of mice on diets C and I. The in vitro fertilizing ability of the sperm decreased to 10% of that of mice on the two control diets. Sperm motility, velocity, linearity and amplitude of lateral head (ALH) displacement were also decreased in 15‐month‐old F‐1 male mice on diet G.     

家蝇资源的利用

在传统观念中，家蝇是肮脏和疾病的化身。但是事实上，家蝇虫体含有丰富的资源。它作为一种资源昆虫已经日益的被人们开发和利用。它在食品、饲料、医药、保健品、生化制剂、农药、化工等行业中有着广泛的用途。     

~(147)Pm对小鼠生殖细胞的遗传毒理效应

本文研究观察了小鼠静脉摄入重核裂变产物~(147)Pm后不同间隔时间对生殖细胞染色体畸变和精子(主要是无钩精子)畸形的诱变效应,实验结果发现~(147)Pm可诱发精原细胞染色体结构畸变;随着机体受内污染时间的延长,染色体畸变率和多倍体细胞也有所增加,同时~(147)Pm也可诱发初级精母细胞产生染色体断片和易位,形成多价体。染色体断片率随~(147)Pm辐照时间的延长而升高。而多价体只在内污染10天后的实验组中出现。     

Electroantennogram responses ofScolytus multistriatus (Coleoptera: Scolytidae) to its pheromone components and to associated compounds

Electroantennograms were recorded fromScolytus multistriatus in response to 4-methyl-3-heptanol, the four geometric isomers of multistriatin, and cubeb oil. Charateristic dose-response curves for response amplitude and the time required for the voltage trace to return to 1/2 baseline (recovery rate) were established. Recovery rates were significantly more rapid following stimulation with 4-methyl-3-heptanol or cubeb oil than with the multistriatin isomers. At most intensities, -multistriatin, the isomer that evokes behavioral response, gave significantly larger EAGs with significantly longer recovery rates than the other isomers. Results of differential adaptation experiments suggested that 4-methyl-3-heptanol interacted with the processes involving multistriatin and cubeb oil activity. However, cross-activity of acceptors for these compounds seems unlikely; single sensillum recordings are needed to ascertain the response spectra for individual receptor neurons.From a thesis submitted as partial fulfillment of the Masters of Science degree, Department of Environmental and Forest Biology, SUNY College of Environmental Science and Forestry, Syracuse, New York 13210.     

Video-enhanced microscopy with a computer frame memory

Video-enhanced microscopy combined with the use of a computer frame memory extends considerably the useful range of our video enhanced contrast (AVEC) methods for polarizing, double-beam interference and differential interference contrast microscopy. Increased visual contrast is achieved by two stages of amplifications: the first optical, by using high bias retardation settings, and the second electronic. These steps are followed by a reduction of background brightness by means of a clamp voltage applied to a DC restoration circuit of the video camera. One of the limitations of the AVEC method alone is the inevitable appearance under high gain conditions of a pattern of mottle due to inaccessible dirt and defects in the lenses even of high quality. This limitation has been circumvented by storing the mottle pattern in the frame memory (frame store) and continuously subtracting it from each succeeding frame to clear the image. A major gain in image quality has resulted. In polarizing microscopy, the frame memory can be used also to subtract the image at one compensator setting from that at the equivalent setting of opposite sign, thus removing from the final image not only most of the mottle pattern but also the contrast due to the bright-field contrast. In the polarizing microscope, these manipulations of the raw video image make it possible to observe and measure the birefringence of various organelles and elements such as microtubules, intermediate filaments and bundles of as few as a half dozen actin filaments. Since scattered light is also removed from the image, features hidden from view in the unprocessed image become visible. In differential interference microscopy, the AVEC method makes visible (i.e. detectable) many linear elements and particles that are an order of magnitude smaller than the resolution limit and not visible in the optical image. Such features are inflated by diffraction, however, to Airy disk size.     

Parentally provided alkaloid does not protect eggs ofUtetheisa ornatrix (Lepidoptera: Arctiidae) against entomopathogenic fungi

Eggs ofUtetheisa ornatrix proved equally vulnerable to fungal infection (Beauveria bassiana, Paecilomyces lilacinus) whether they contained parentally provided pyrrolizidine alkaloid (monocrotaline) or were free of such alkaloid. In in vitro tests, monocrotaline, either as free base or N-oxide, had no inhibiting effect on fungal cultures.Report No. 99 of the series Defense Mechanisms of Arthropods; No. 98 is Attygalle et al.,Experientia (in press).     

Toxicological action and ecological importance of plant photosensitizers

This review discusses the biochemical action and ecological significance of phototoxic phytochemicals. Mechanistic details of photosensitization as well as cellular and molecular targets of plant-derived phototoxins in model biological systems (microbial and in vitro) and in herbivorous insects are described. Findings from these studies suggest the potential importance of phototoxic plant metabolites in plant-insect interactions. Aspects of phototoxin distribution and significance in diverse ecosystems are considered, and areas for future research are suggested.     

The Plant Stress Hypothesis and Variable Responses by Blue Grama Grass (<Emphasis Type="Italic">Bouteloua gracilis</Emphasis>) to Water,Mineral Nitrogen,and Insect Herbivory

Acting simultaneously or sequentially, plants encounter multiple stresses from combined abiotic and biotic factors that result in decreased growth and internal reallocation of resources. The plant stress hypothesis predicts that environmental stresses on plants decrease plant resistance to insect herbivory by altering biochemical source–sink relationships and foliar chemistry, leading to more palatable food. Such changes in the nutritional landscape for insects may facilitate insect population outbreaks during periods of moderate stress on host plants. We examined the plant stress hypothesis with field experiments in continental grassland (USA) using the C₄ grass Bouteloua gracilis. Water, nitrogen fertilizer, and herbivory from the grass-feeding grasshopper Ageneotettix deorum were manipulated. Combined stresses from water and mineral-N in the soil decreased plant growth and altered foliar percent total N (TN) and percent total nonstructural carbohydrate (TNC) concentrations in an additive fashion. Grasshopper herbivory affected final biomass only in dry years; plants compensated for tissue loss when rainfall was abundant. Foliar TN and TNC concentrations were dynamic with respect to variable climatic conditions and treatment combinations, showing significant interactions. Grasshopper herbivory had its greatest impact on TN or TNC in dry years, interacting with other forms of stress. Herbivory as a single factor had strong effects on TNC in years with normal precipitation, but not in a dry year. Performance (developmental rate and survival) by the grasshoppers Phoetaliotes nebrascensis and A. deorum were not greatly affected by plant stress in a manner consistent with the plant stress hypothesis.