炎症免疫刺激对孕鼠胚胎基因表达谱影响的研究

目的:探讨妊娠期大鼠经炎症免疫刺激后对胚胎基因表达谱的影响.方法:选取6只孕鼠,分别腹腔注射LPS及Zymosan后,取胚胎抽提总RNA,经纯化反转录等过程合成生物素标记的cRNA,经片断化后与Rat Genome 230 2.0 Array芯片杂交,读取芯片结果并进行分析.结果:LPS组有183个基因上调、270个基因表达下调,Zymosan组有144个基因表达上调、417个基因表达下调.有50个基因在上述两组中均表达上调,其中已知功能的有9个;有173个基因在上述两组中表达均下调,已知功能的有85个.结论:应用全基因组芯片筛选了孕鼠经炎症刺激后胚胎差异表达的基因,为进一步研究孕鼠经炎症刺激后仔鼠血压升高的机制提供了新的思路.     

Effects on Fertility in Transgenic Tobacco by Localized Expression of ipt Gene

The isopenteryl transferase (ipt) gene from Agrobacterium tumefaciens (Smith et Townsend) Conn was driven under the tobacco TA29 promoter and introduced into tobacco ( Nicotiana tabacum L.) plants by A. tumefaciens mediated transformation. PCR and Southern blot analysis confirmed that the ipt gene has integrated into the genomes of tobacco plants. The expression pattern of this chimeric TA29-ipt gene in the transgenic plants was studied, and the endogenous cytokinin level in different organs was assayed by ELISA method. The results showed that the cytokinin content in the androecium of transgenic plants increased 3-4 times as compared with the control, and some changes of the fertility of the TA29-ipt transgenic plants have been observed.     

ipt基因定位表达对转基因烟草育性的影响

杂种优势是生物界的一种普遍现象。作物杂种优势的利用是培育高产、抗逆、优质新品种的重要手段之一。然而 ,常规育种技术获得配套三系的难度很大 ,由此限制了杂种优势利用的发展。近年来应用转基因技术创造雄性不育植株已有不少报道[1- 5] 。有研究表明 ,自然突变的雄性不育株     

Time-Dependent Effects of Trichloroethylene on Motor Activity in Rats

Circadian variations in acute and subacute neurobehavioural effects of trichloroethylene (TRI: 1.2 g/kg i.p.) were investigated in the rat under a light: dark = 12:12 hr cycle. An acute effect of TRI evaluated by decreased muscle tone was maximal during the early dark phase (21:00). A subacute effect of TRI was evaluated by a continuous recording of spontaneous locomotor activity in the rat. The circadian rhythm in spontaneous locomotor activity was extensively impaired by the injection of TRI for three consecutive days. Spectral analysis of spontaneous locomotor activity showed that ultradian periods became more dominant than the circadian period, and the 1//fluctuation of the spectrum disappeared after the injection of TRI. The effect of TRI on the circadian rhythm in spontaneous locomotor activity was circadian-phase dependent, and the treatment of TRI at 09:00 provoked greater circadian rhythm impairment than that at 21:00. The mechanisms of the time-dependent effect of TRI on neurobehaviour are the subject of further investigation.     

Time-Dependent Effects of Trichloroethylene on Motor Activity in Rats

Circadian variations in acute and subacute neurobehavioural effects of trichloroethylene (TRI: 1.2 g/kg i.p.) were investigated in the rat under a light: dark = 12:12 hr cycle. An acute effect of TRI evaluated by decreased muscle tone was maximal during the early dark phase (21:00). A subacute effect of TRI was evaluated by a continuous recording of spontaneous locomotor activity in the rat. The circadian rhythm in spontaneous locomotor activity was extensively impaired by the injection of TRI for three consecutive days. Spectral analysis of spontaneous locomotor activity showed that ultradian periods became more dominant than the circadian period, and the 1//fluctuation of the spectrum disappeared after the injection of TRI. The effect of TRI on the circadian rhythm in spontaneous locomotor activity was circadian-phase dependent, and the treatment of TRI at 09:00 provoked greater circadian rhythm impairment than that at 21:00. The mechanisms of the time-dependent effect of TRI on neurobehaviour are the subject of further investigation.     

Dexamethasone Influences Human Clock Gene Expression in Bronchial Epithelium and Peripheral Blood Mononuclear Cells in vitro

We determined whether human peripheral blood mononuclear cells (PBMCs) could be used to analyze clock genes by studying their mRNA expressions in human bronchial epithelium (BEAS‐2B) and PBMCs following stimulation by the glucocorticoid homologue dexamethasone (DEX) in vitro. PBMCs were obtained at 10:00 h from two diurnally active (～07:00 to 23:00 h) healthy volunteers and were evaluated for hPer1 mRNA expression following DEX stimulation in vitro using real time‐PCR analysis. DEX stimulation of human BEAS‐2B cells and PBMCs in vitro led to a remarkable increase of hPer1 mRNA. The glucocorticoid rapidly affected the expression of hPer1 mRNA in PBMCs, suggesting that human PBMCs may be a useful surrogate marker for the investigation of drug effects on clock genes.     

Effects of Nocturnal Light on (Clock) Gene Expression in Peripheral Organs: A Role for the Autonomic Innervation of the Liver

Background

The biological clock, located in the hypothalamic suprachiasmatic nucleus (SCN), controls the daily rhythms in physiology and behavior. Early studies demonstrated that light exposure not only affects the phase of the SCN but also the functional activity of peripheral organs. More recently it was shown that the same light stimulus induces immediate changes in clock gene expression in the pineal and adrenal, suggesting a role of peripheral clocks in the organ-specific output. In the present study, we further investigated the immediate effect of nocturnal light exposure on clock genes and metabolism-related genes in different organs of the rat. In addition, we investigated the role of the autonomic nervous system as a possible output pathway of the SCN to modify the activity of the liver after light exposure.

Methodology and Principal Findings

First, we demonstrated that light, applied at different circadian times, affects clock gene expression in a different manner, depending on the time of day and the organ. However, the changes in clock gene expression did not correlate in a consistent manner with those of the output genes (i.e., genes involved in the functional output of an organ). Then, by selectively removing the autonomic innervation to the liver, we demonstrated that light affects liver gene expression not only via the hormonal pathway but also via the autonomic input.

Conclusion

Nocturnal light immediately affects peripheral clock gene expression but without a clear correlation with organ-specific output genes, raising the question whether the peripheral clock plays a “decisive” role in the immediate (functional) response of an organ to nocturnal light exposure. Interestingly, the autonomic innervation of the liver is essential to transmit the light information from the SCN, indicating that the autonomic nervous system is an important gateway for the SCN to cause an immediate resetting of peripheral physiology after phase-shift inducing light exposures.     

Time-Dependent Effects of Training on Cardiovascular Control in Spontaneously Hypertensive Rats: Role for Brain Oxidative Stress and Inflammation and Baroreflex Sensitivity

Baroreflex dysfunction, oxidative stress and inflammation, important hallmarks of hypertension, are attenuated by exercise training. In this study, we investigated the relationships and time-course changes of cardiovascular parameters, pro-inflammatory cytokines and pro-oxidant profiles within the hypothalamic paraventricular nucleus of the spontaneously hypertensive rats (SHR). Basal values and variability of arterial pressure and heart rate and baroreflex sensitivity were measured in trained (T, low-intensity treadmill training) and sedentary (S) SHR at weeks 0, 1, 2, 4 and 8. Paraventricular nucleus was used to determine reactive oxygen species (dihydroethidium oxidation products, HPLC), NADPH oxidase subunits and pro-inflammatory cytokines expression (Real time PCR), p38 MAPK and ERK1/2 expression (Western blotting), NF-κB content (electrophoretic mobility shift assay) and cytokines immunofluorescence. SHR-S vs. WKY-S (Wistar Kyoto rats as time control) showed increased mean arterial pressure (172±3 mmHg), pressure variability and heart rate (358±7 b/min), decreased baroreflex sensitivity and heart rate variability, increased p47^phox and reactive oxygen species production, elevated NF-κB activity and increased TNF-α and IL-6 expression within the paraventricular nucleus of hypothalamus. Two weeks of training reversed all hypothalamic changes, reduced ERK1/2 phosphorylation and normalized baroreflex sensitivity (4.04±0.31 vs. 2.31±0.19 b/min/mmHg in SHR-S). These responses were followed by increased vagal component of heart rate variability (1.9-fold) and resting bradycardia (−13%) at the 4th week, and, by reduced vasomotor component of pressure variability (−28%) and decreased mean arterial pressure (−7%) only at the 8th week of training. Our findings indicate that independent of the high pressure levels in SHR, training promptly restores baroreflex function by disrupting the positive feedback between high oxidative stress and increased pro-inflammatory cytokines secretion within the hypothalamic paraventricular nucleus. These early adaptive responses precede the occurrence of training-induced resting bradycardia and blood pressure fall.     

Effects of a High-Fat Diet and Strain on Hypothalamic Gene Expression in Rats

Objective: This study was designed to investigate whether dietary fat and genetic background might differentially alter the expression of hypothalamic genes involved in food intake. Research Methods and Procedures: Three-month-old Osborne-Mendel (OM) and S5B/Pl rats were fed either a high-fat or a low-fat diet for 14 days. mRNA for neuropeptide Y (NPY), corticotrophin-releasing hormone, NPY Y-1 receptor and Y-5 receptor, and serotonin 2c (5-HT2c) receptors were measured using Northern blotting or ribonuclease protection assays. Results: OM rats showed an increased expression of NPY and corticotrophin-releasing hormone compared with S5B/Pl rats. The expression of NPY-Y1 and -Y5 receptor mRNA was significantly higher in the hypothalamus of OM rats compared with S5B/Pl rats. The expression of 5HT-2c receptor mRNA was significantly reduced in both strains of rats eating a high-fat diet when compared with the animals eating the low-fat diet. Discussion: These data suggest that over activity of the NPY system may contribute to the development of obesity in OM rats and that expression of the 5HT-2c receptor gene may be modulated by dietary fat.     

人外周血淋巴细胞核心钟基因Clock和Bmal1的昼夜节律性表达

探讨自然光制下正常成年人外周血淋巴细胞钟基因Clock和Bmal1的昼夜节律性表达。用实时定量RT-PCR方法,测定不同昼夜时点(ZT)受试者外周血淋巴细胞总RNA中核心钟基因Clock和Bmal1的mRNA表达量,通过余弦法和Clock Lab软件获取节律参数,并经振幅检验分析是否存在昼夜节律。结果发现正常成年人外周血淋巴细胞钟基因Clock和Bmal1的mRNA表达呈昼夜节律性振荡(P0.05),Clock的峰时和谷时分别位于ZT13和ZT1,Bmal1的峰时和谷时分别位于ZT12和ZT24;两个基因在所检测的各个昼夜时点中表达水平均有明显差异(P0.05),Bmal1的表达水平较Clock降低;二者表达的峰值相位、振幅、峰时和谷时相一致(P0.05),但Bmal1转录的中值水平以及峰时mRNA水平和谷时mRNA水平降低(P0.05)。提示正常成年人外周血淋巴细胞钟基因Clock和Bmal1的表达存在同步化的昼夜节律性转录特征。     

红细胞生成素基因在大鼠体内的表达及表达产物的生物学效应

红细胞生成素（ｅｒｙｔｈｒｏｐｏｉｅｔｉｎ,ＥＰＯ）是一种由胎儿肝脏和成人肾脏产生的多肽类生长因子,在体内的表达具有严格的组织特异性,因此,慢性肾病所引起的贫血常常难以得到有效的治疗．随着基因治疗技术的不断成熟与完善,尤其是近年一些实验室先后发现质粒...     

Styrene Altered Clock Gene Expression in Serum-Shocked Cultured Human Fibroblasts

The circadian clock can regulate the metabolic process of xenobiotics, but little is known as to circadian rhythms can be perturbed by xenobiotics. Styrene is a organic chemical widely used in occupational settings. The effects of styrene on the circadian genes of HuDE cells were evaluated after serum-shocking synchronization. A subtoxic dose of 100 µM of styrene altered the expression of clock genes BMAL1, PER2, PER3, CRY1, CRY2, and REV-ERB-α.     

橄榄叶提取物对大鼠急性炎症和痛觉过敏的研究

本文采用鹿角菜胶诱导的大鼠急性炎症模型观察橄榄叶提取物(OLE)的抗炎与镇痛作用及对致炎因子TNF-α和IL-1β的mRNA表达。用鹿角菜胶注射到大鼠右后足内,分别于鹿角菜胶注射前30 min和注射后120 min灌胃给予OLE 100、250和500 mg/kg体重。鹿角菜胶处理后测量足跖肿胀度及痛域。用RT-PCR检测足跖垫内组织TNF-α、IL-1β和IL-10的mRNA表达。结果显示,经灌胃给予OLE100、250和500 mg/kg体重,均能明显降低大鼠后足肿胀度,增加痛域,并明显降低致炎因子TNF-α和IL-1β的mRNA表达。本研究提示OLE具有抗炎和镇痛作用,其作用机制可能与抑制TNF-α和IL-1β的mRNA表达有关。     

Localized RNAi and Ectopic Gene Expression in the Medicinal Leech

In this video, we show the use of a pneumatic capillary gun for the accurate biolistic delivery of reagents into live tissue. We use the procedure to perturb gene expression patterns in selected segments of leech embryos, leaving the untreated segments as internal controls.The pneumatic capillary gun can be used to reach internal layers of cells at early stages of development without opening the specimen. As a method for localized introduction of substances into living tissues, the biolistic delivery with the gun has several advantages: it is fast, contact-free and non-destructive. In addition, a single capillary gun can be used for independent delivery of different substances. The delivery region can have lateral dimensions of ~50-150 µm and extends over ~15 µm around the mean penetration depth, which is adjustable between 0 and 50 µm. This delivery has the advantage of being able to target a limited number of cells in a selected location intermediate between single cell knock down by microinjection and systemic knockdown through extracellular injections or by means of genetic approaches.For knocking down or knocking in the expression of the axon guidance molecule Netrin, which is naturally expressed by some central neurons and in the ventral body wall, but not the dorsal domain, we deliver molecules of dsRNA or plasmid-DNA into the body wall and central ganglia. This procedure includes the following steps: (i) preparation of the experimental setup for a specific assay (adjusting the accelerating pressure), (ii) coating the particles with molecules of dsRNA or DNA, (iii) loading the coated particles into the gun, up to two reagents in one assay, (iv) preparing the animals for the particle delivery, (v) delivery of coated particles into the target tissue (body wall or ganglia), and (vi) processing the embryos (immunostaining, immunohistochemistry and neuronal labeling) to visualize the results, usually 2 to 3 days after the delivery.When the particles were coated with netrin dsRNA, they caused clearly visible knock-down of netrin expression that only occurred in cells containing particles (usually, 1-2 particles per cell). Particles coated with a plasmid encoding EGFP induced fluorescence in neuronal cells when they stopped in their nuclei.Download video file.^{(116M, mov)}     

Time-Dependent Effect of Surface Material on Lactobacillus rhamnosus GG Biofilm Formation and Gene Expression

Microbiology - Formation of Lactobacillus rhamnosus GG biofilm on three different abiotic supports (glass, stainless steel, and polystyrene) over a five-day incubation period was investigated. The...