Visualization of chromatin folding patterns in chicken erythrocytes by atomic force microscopy （AFM）

The organization of the higher order structure of chromatin in chicken erythrocytes has been examined with tapping-mode scanning force microscopy under conditions close to their native envirinment.Reproducible highresolution AFM images of chromatin compaction at several levels can be demonstrated.An extended beads-on-astring (width of - 15-20nm,height of - 2-3nm for each individual nucleosome) can be consistently observed.Furthermore,superbeade (width of - 40nm,height of - 7nm) are demonstrated.Visualization of the solenoid conformation at the level of 30nm chromatin fiber is attained either by using AFM or by using electron microscopy.In addition,tightly coiled chromatin fibers (- 50-60nm and - 90-110nm) can be revealed.Our data suggest that the chromatin in the interphase nucleus of chicken erythrocyte represents a high-order conformation and AFM provides useful high-resolution structural information concerning the folding pattern of interphase chromatin fibers.     

Nitrogen and carbon isotope responses of Chinese cabbage and chrysanthemum to the application of liquid pig manure

The effects of the liquid pig manure (LM) used in organic farming on the natural abundance of ¹⁵N and ¹³C signatures in plant tissues have not been studied. We hypothesized that application of LM will (1) increase δ¹⁵N of plant tissues due to the high δ¹⁵N of N in LM as compared with soil N or inorganic fertilizer N, and (2) increase δ¹³C of plant tissues as a result of high salt concentration in LM that decreases stomatal conductance of plants. To test these hypotheses, variations in the δ¹⁵N and δ¹³C of Chinese cabbage (Brassica campestris L.) and chrysanthemum (Chrysanthemum morifolium Ramatuelle) with two different LMs (with δ¹⁵N of +15.6 and +18.2‰) applied at two rates (323 and 646 kg N ha^-1 for cabbage and 150 and 300 kg N ha^-1 for chrysanthemum), or urea (δ¹⁵N = -2.7‰) applied at the lower rate above for the respective species, in addition to the control (no N input) were investigated through a 60-day pot experiment. Application of LM significantly increased plant tissue δ¹⁵N (range +9.4 to +14.9‰) over the urea (+3.2 to +3.3‰) or control (+6.8 to 7.7‰) treatments regardless of plant species, strongly reflecting the δ¹⁵N of the N source. Plant tissue δ¹³C were not affected by the treatments for cabbage (range −30.8 to −30.2‰) or chrysanthemum (−27.3 to −26.8‰). However, cabbage dry matter production decreased while its δ¹³C increased with increasing rate of LM application or increasing soil salinity (P < 0.05), suggesting that salinity stress caused by high rate of LM application likely decreased stomatal conductance and limited growth of cabbage. Our study expanded the use of the δ¹⁵N technique in N source (organic vs. synthetic fertilizer) identification and suggested that plant tissue δ¹³C maybe a sensitive indicator of plant response to salinity stress caused by high LM application rates.     

五个鸡群中催乳素基因密码子使用频率与产蛋量的关系分析

通过鸡催乳素基因编码区基因扫描,发现3个SNP位点,分别是外显子2的C1607T、外显子5的C5749T和T5821C,3个SNP均没有改变氨基酸的编码.同时发现不同的单倍型间存在不同的密码子使用频率.对5个鸡群共370只鸡进行SSCP的基因型检测,共发现7种单倍型,结合44周龄产蛋量分析,发现不同单倍型的平均产蛋量存在显著性差异.结合密码子使用频率分析,发现使用高频密码子的单倍型个体产蛋量相对高.通过酶联免疫方法检测催乳素表达量,结果显示,使用高频密码子的个体,激素水平较高,其中使用2个高频密码子的单倍型个体和使用1.5个密码子的单倍型个体之间存在极显著差异.研究结果表明,密码子使用频率与产蛋量在一定的范围内呈现正相关趋势.     

Research of blastocyte-like structure in chicken

The chicken embryo is a classic model used to investigate embryonic development, gene expression, and tissue differentiation, and is also an important research tool in studying the animal functional genomics. The whole blastoderms of fresh unincubated eggs from White Leghorn chickens were collected with a paper ring, mechanically broken into small pieces and cultured in medium. Then the small pieces would develop into blastocyte-like structures (BLS), which could be facilitated by an addition of fetal bovine serum (FBS) to the primary culture and their diameter was nearly doubled from 12 to 24 h. The additional yolk had no positive effect on the development in the first 12 h but encouraged the BLSs attaching and inner cells differentiating instead in 24 h. The inner cells of the BLS showing a high alkaline-phosphatase activity similar to those in mouse embryonic stem (ES) cells and also expressing a large amount of the specific stage embryonic antigen-1 (SSEA-1) on the surface, which was known to be the characteristic of non-differentiated mouse and avian ES cells, could finally differentiate into nerve-like cells, fibroblast cells and so on in the medium. Leukemia inhibitory factor (LIF) facilitated the cells' proliferation and prevented differentiation in the suspended culture of the BLSs. So we drew the conclusion that the BLS obtained from broken blastoderm can be used to amplify avian ES cells so as to initiate a new method of producing transgenic chickens.     

Enzyme cytochemical observations on the tissue stages of the life cycle of Eimeria acervulina and Eimeria necatrix

Cytochemical studies concerning the presence and distribution of various enzymes in the tissue stages of the life cycle of Eimeria acervulina and E. necatrix have been undertaken.Acid and alkaline phosphatases as well as ATPase (pH 7·2) were found to be present in all the stages of the life cycles examined, the latter enzyme being very strong in the plastic granules of the macrogametocytes and in the inner membrane of the oocyst wall. The reaction for all three enzymes was observed in the cytoplasm but not the nucleus. Non-specific esterase and glucose-6-phosphatase were also found in all stages examined, the latter occurring in greater amounts in stages where deposition of glycogen (amylopectin) was pronounced. Succinic dehydrogenase occurred only in the second generation schizonts and merozoites of E. necatrix and in the formed oocysts of both species. No reaction for β-glucuronidase or leucine naphthylamidase was apparent in any stage, although a slight reaction for leucine naphthlyamidase was seen in the second generation merozoites of E. necatrix lying free in the intestinal lumen.The presence and distribution of these enzymes and their possible function were discussed.     

非水虻源微生物与武汉亮斑水虻幼虫联合转化鸡粪的研究

【目的】益生微生物在协助亮斑扁角水虻幼虫转化有机废弃物、提高其转化效率方面具有重要的作用,本研究针对非水虻源微生物,开展与水虻联合转化鸡粪的研究,以阐明外源微生物在水虻转化畜禽粪便中的作用,对其转化机制的研究及产业化生产具有重要意义。【方法】采用稀释涂平板的方法进行鸡粪堆肥和猪粪堆肥中细菌的分析,并将筛选到的细菌分别接种到无菌的鸡粪基质中与武汉亮斑水虻幼虫联合转化,通过称重法测定转化后武汉亮斑水虻及鸡粪的重量,评价转化效果及对幼虫的影响,然后将促进转化效果明显的菌株按不同比例进行复配,与武汉亮斑水虻幼虫联合转化新鲜鸡粪,分析复配菌剂对武汉亮斑水虻幼虫转化鸡粪的影响。【结果】结果显示R-07、R-09、F-03和F-06在促进武汉亮斑水虻幼虫生长和鸡粪转化的效果上最为显著。与对照组相比,水虻幼虫转化率分别提高了27.21%、15.00%、9.93%和16.29%;基质减少率分别提高了17.94%、10.42%、7.84%和9.27%。将这4株细菌配制复配菌剂与武汉亮斑水虻幼虫联合转化鸡粪,结果显示复配比例为R-07:R-09:F-03:F-06=4:1:1:1时效果最好,与空白对照相比,武汉亮斑水虻幼虫存活率提高了10.25%,幼虫虫重增加了28.41%,幼虫转化率增加了30.46%,鸡粪减少率增加了7.69%。【结论】添加通过筛选优化的非水虻来源的微生物复合菌剂能够促进水虻高效转化鸡粪,研究结果有助于改善现有的武汉亮斑水虻幼虫转化体系,为开发新型的联合转化工艺、更加有效地处理畜禽粪便奠定基础。     

奶牛粪酸臭成分降解过程中的微生物群落变化

【目的】研究可降解成年泌乳奶牛粪中主要酸臭物的微生物群落的组成及动态变化。【方法】利用牛粪堆肥环境中的微生物进行了发酵优化、菌种驯化以及酸臭有机物降解规律的研究,结合r DNA高通量测序技术对有益微生物的组成及相对生物量进行了分析。【结果】实验发现,奶牛排泄物中的臭味来源主要为短链有机酸,堆肥自然环境中的微生物可以有效地对有机酸等污染物进行去除,经从低到高浓度的有机酸臭物(W/V,0.1%–0.2%)驯化发酵后,培养物中原核微生物以芽孢杆菌居多,而真核微生物主要由红曲霉及粉状毕赤酵母组成。【结论】进一步推测这几种微生物是耐受并降解有机酸臭物的优势微生物,可以应用于奶牛养殖过程中酸臭排泄物的生物控制。     

城关社区成人水痘并发症76例诊治分析

目的了解成人水痘并发症的临床特点,为成人水痘的预防和临床诊治提供依据。方法回顾性分析2011~2015年我院收治的76例成人水痘并发症患者的临床资料,对临床流行特征和并发症发生情况及预后进行分析。结果 76例成人水痘并发症患者继发皮肤感染占84.21%,肝功能损害占55.26%,呼吸道感染占47.37%;发病比例男性高于女性,且以冬春季节发病为主。76例患者经临床应用阿昔洛韦联合麻疹减毒活疫苗治疗,均治愈。结论成人水痘发病率有增高趋势,而且成人水痘并发症有发热程度和热程、全身毒血症状以及皮疹数量、各种并发症发生比例均较儿童高且严重,无疫苗免疫史患者病情较重。临床上应尽早明确诊断,及时治疗;可通过接种水痘减毒活疫苗(VarV)(建议推行2剂次接种的免疫策略)来控制发病率和减少并发症发生。     

Heavy metal accumulation in wheat and barley: The effects of soil presence and liquid manure amendment

An experiment was undertaken to evaluate the effect of liquid manure amendment on heavy metal accumulation in wheat and barley. For this purpose, both kinds of seedlings were grown simultaneously in a Petri dish, while wheat seedlings were also grown in pots containing unpolluted agricultural soil. All of the seedlings were irrigated with one of the three prepared solutions: artificial rainwater solution, heavy metal solution and liquid manure solution containing NH₄NO₃, H₃PO₄ and KOH along with equal amounts of heavy metals as in the second solution. Twenty days later, 1 g of plant tissue was digested with the mixture of HNO₃ and H₂O₂ for ICP-OES/HG-ICP-OES analysis. The results showed that the uptake of arsenic and mercury was highest for both plants grown in a Petri dish. Furthermore, the wheat grown in a Petri dish also had a high content of nickel, cadmium and copper, while the pot-grown wheat contained high amounts of iron and manganese, probably due to the adsorption of nickel, cadmium, copper and mercury on soil phases. The lower uptake of all heavy metals was observed after the amendment of liquid manure, with the exception of manganese in wheat and mercury in all plants.     

Visual Ecology and Perception of Coloration Patterns by Domestic Chicks

This article suggests how we might understand the way potential predators see coloration patterns used in aposematism and visual mimicry. We start by briefly reviewing work on evolutionary function of eyes and neural mechanisms of vision. Often mechanisms used for achromatic vision are accurately modeled as adaptations for detection and recognition of the generality of optical stimuli, rather than specific stimuli such as biological signals. Colour vision is less well understood, but for photoreceptor spectral sensitivities of birds and hymenopterans there is no evidence for adaptations to species-specific stimuli, such as those of food or mates. Turning to experimental work, we investigate how achromatic and chromatic stimuli are used for object recognition by foraging domestic chicks (Gallus gallus). Chicks use chromatic and achromatic signals in different ways: discrimination of large targets uses (chromatic) colour differences, and chicks remember chromatic signals accurately. However, detection of small targets, and discrimination of visual textures requires achromatic contrast. The different roles of chromatic and achromatic information probably reflect their utility for object recognition in nature. Achromatic (intensity) variation exceeds chromatic variation, and hence is more informative about change in reflectance – for example, object borders, while chromatic signals yield more information about surface reflectance (object colour) under variable illumination. This revised version was published online in July 2006 with corrections to the Cover Date.