农民“谈鼠色变”

农民“谈鼠色变”近来，不少农民反映：农村鼠害十分严重，成群成串的家、野鼠，不分白天黑夜危害庄稼、家禽家畜和传播鼠疫，成为农村一大公害，农民＂谈鼠色变＂。据初步调查：某县２４个乡镇所在地、农户家中、庄稼地和林木区内均有不同程度的鼠害。尤其对庄稼的危害十...

5-羟色胺转运体敲除小鼠行为学与其海马PKA/CREB/BDNF信号通路水平变化的研究

目的:研究5-羟色胺转运体(5-HTT)敲除小鼠行为学及其海马蛋白激酶A/环磷酸腺苷反应元件结合蛋白/脑源性神经营养因子(PKA/CREB/BDNF)信号转导通路蛋白表达水平的变化。方法:实验动物分为5-HTT表达消失(5-HTT-/-)、5-HTT表达降低(5-HTT+/-)及野生型(5-HTT+/+)3组,每组10只,通过旷场实验和强迫游泳对3组小鼠探究活动能力以及焦虑、紧张、抑郁等心理行为进行比较评估,Western blotting检测其海马PKA/CREB/BDNF通路蛋白表达水平。结果:旷场实验中5-HTT-/-组的站立次数、水平移动格数、中央区移动格数、中央区进入次数均少于5-HTT+/+组及中央区活动时间短于5-HTT+/+组(均P<0.05),5-HTT+/-组的水平移动格数、中央区移动格数均少于5-HTT+/+组(P<0.05);强迫游泳中5-HTT-/-组小鼠的不动时间长于5-HTT+/-组和5-HTT+/+组,5-HTT+/-组的不动时间长于5-HTT+/+组(P<0.05)。与5-HTT+/+组相比,5-HTT-/-组小鼠海马中蛋白激酶A(PKA)、环磷酸腺苷反应元件结合蛋白(CREB)和脑源性神经营养因子(BDNF)表达均减少(P<0.05),5-HTT+/-组PKA表达减少(P<0.05);与5-HTT+/-组相比,5-HTT-/-组小鼠海马中BDNF表达减少(P<0.05)。结论:5-HTT基因敲除可能导致小鼠海马区PKA/CREB/BDNF信号通路表达水平下调,从而使机体产生焦虑、抑郁、紧张等心理行为问题。

老鼠与数字

鼠的种类繁多,据专家研究说,地球上有老鼠1800余种,其数量亦十分惊人,估计目前我国有“鼠口”35亿只,全世界在120亿只以上。 老鼠出现在距今3500万年的渐新世。

鼠年伊始防“五病”

在十二生肖中,“鼠”大概是最不受人们欢迎的,什么抱头鼠窜、鼠目寸光啦,什么鼠窃狗盗、鼠头鼠脑啦等等,难怪鼠年来临,大众传媒一个个都噤若寒蝉,谈鼠色变。其实,老鼠并不可怕,可怕的是我们自身免疫力、抵抗力不强,使病菌长驱直入,诱发多种疾病。因此,于鼠叩门,有必要早打预防针,警惕五种“病”: 一是“虚胖病”。新年伊始,将本地区、本部门的经济发展,各项工作订个计划,使全体同志能够“

Changes of Estrogen in Serum and Estrogen Receptor β in the Relevant Brain Regions Following Mating Behavior of the Male Mandarin Vole Microtus mandarinus

In order to investigate the estrogen and estrogen receptor β changes after mating behavior of male mandarin vole （Microtus mandarinus）, the radioimmunoassay （RIA） and immunohistochemistry methods were used to investigate changes of the serum estrogen （E） concentrations, estrogen immunoreactive neurons （E-IRs） and estrogen receptor β immunoreactive neurons （ERβ-IRs） in the relevant brain regions following mating behavior. Fifteen sexually matured male voles were randomly divided into three groups and treated differently： （1） control group： voles were exposed to clean hard-wood shavings （n=5）, （2） exposure group： voles were exposed to the soiled bedding for more than 24h on which estrous females had been placed （n=5）, and （3） mating group： voles were placed with an estrous female for more than 24h （n=5）. The results showed circulating serum E concentrations were significantly higher in the mating group than in the exposure group and the control group, and there were no significant difference between the exposure group and the control group. E-IRs and ERβ-IRs were detected in the following brain regions related to mating behavior： the arcuate nucleus （ARC）, bed nucleus of the stria terminalis （BST）, lateral septal nucleus （LS）, medial amygdaloid nucleus （ME）, medial preoptic area （MPO） and ventromedial hypothalamic nucleus （VMH）. The results showed that there were significantly more E-IRs in the six brain regions in the mating group than in the control group and the exposure group, and there were no significant difference between the exposure group and the control group except for LS. There was no significant difference in ERβ-IRs in the six brain regions among the three groups, and there were some lighter -stained ERβ-IRs in these brain regions. The results suggested that estrogen affect mating activity of male mandarin voles, but ERβ might not play an important role in mating behavior of male mandarin voles. Instead, it might be through other receptors.

Actin Visualization in Living Immature Pollen of Rice Using a GFP-Mouse Talin Fusion Protein

Green fluorescent protein (GFP) fused to the F_actin binding domain of mouse talin labels the actin cytoskeleton in the immature pollen of stable transformed rice (Oryza sativa L.) plants. Actin microfilaments could be visualized only in the late_developmental stage of the immature pollen. During this developmental stage, microfilaments, initially composed of very short fibrils, develop into a very complex and novel network that sometimes totally and sometimes partially encloses the vegetative nucleus and the spherical shaped generative cell in the central cytoplasm of the immature pollen. The behavior of the actin microfilamentous structure throughout the late_developmental stage of the immature pollen is extremely dynamic, and the likelihood of this structure in generating forces for vegetative nucleus and generative cell movement in the immature pollen has been discussed. No actin filaments were visualized in the spherical generative cells.

Determination of trans-resveratrol in mouse liver by high performance liquid chromatography

To develop a sensitive high performance liquid chromatography （HPLC） assay for the determination of trans-resveratrol in mouse liver. The whole liver of a mouse was removed from the body, homogenated, and extracted by ethyl acetate. The organic layer was isolated and evaporated to dryness, the residue was reconstituted in 0.2 mL mobile phase for centrifugation, and 50 uL of the supernatant was injected into the/-IPLC instrument. The sample was separated on a Shimadzu ODS column （150 mm × 4.6 mm, 5 um） at 35 ℃ and detected by ultraviolet （UV） detector at the wavelength of 305 nm. The mobile phase consisted of methanol and 0.1 mol/L acetic acid （4：6, v/v） with the flow-rote at 1 mL/min. The limit of detection was 3.0 ng/g in liver homogenate with a signal/noise ratio of 3：1. The linear range of the calibration curve was 5.0-120.0 ng/g. The mean recoveries at the concentrations of 6, 10 and 80 ng/g were 102%, 96.0% and 91.5%, respectively. The RSDs for inter- and intra-day assays were less than 5%. Compared with other reported methods, this method was faster and more sensitive. It was also proved to be of good linearity, selectivity, accuracy and precision, and can be efficiently applied to the pharmacoldnetic study of trans-resveratrol in mouse liver.

Lansoprazole ameliorates intestinal mucosal damage induced by ischemia-reperfusion in rats

AIM: To investigate the protective effect of lansoprazoleon ischemia and reperfusion (I/R)-induced rat intestinalmucosal injury in vivo.METHODS: Intestinal damage was induced by clampingboth the superior mesenteric artery and the celiac trunkfor 30 rain followed by reperfusion in male Sprague-Dawleyrats. lansoprazole was given to rats intraperitoneally 1 hbefore vascular clamping.RESULTS: Both the intraluminal hemoglobin and proteinlevels, as indices of mucosal damage, significantlyincreased in I/R-groups comparion with those of sham-operation groups. These increases in intraluminal hemoglobinand protein levels were significantly inhibited by the treatmentwith lansoprazole at a dose of 1 mg/kg. Small intestineexposed to I/R resulted in mucosal inflammation that wascharacterized by significant increases in thiobarbituric acid-reactive substances (TBARS), tissue-associatedmyeloperoxidase activity (MPO), and mucosal content of ratcytokine-induced neutrophil chemoattractant-1 (CINC-1).These increases in TBARS, MPO activities and CINC-1 contentin the intestinal mucosa after I/R were all inhibited bypretreatment with lansoprazole at a dose of 1 mg/kg.Furthermore, the CINC-1 mRNA expression was increasedduring intestinal I/R, and this increase in mRNA expressionwas inhibited by treatment with lansoprazole.CONCLUSION: Lansoprazole inhibits lipid peroxidation andreduces development of intestinal mucosal inflammationinduced by I/R in rats, suggesting that lansoprazole mayhave a therapeutic potential for I/R injury.

Chromatin-binding in vivo of the erythroid kruppel-like factor,EKLF,in the murine globin loci

EKLF is an erythroid-specific, zinc finger-containing transcription factor essential for the activation of the mammalian beta globin gene in erythroid cells of definitive lineage. We have prepared a polyclonal anti-mouse EKLF antibody suitable for Western blotting and immunoprecipitation （IP） qualities, and used it to define the expression patterns of the EKLF protein during mouse erythroid development. We have also used this antibody for the chromatin-immunoprecipitation （CHIP） assay. EKLF was found to bind in vivo at both the mouse beta-major-globin promoter and the HS2 site of beta-LCR in the mouse erythroleukemia cells （MEL） in a DMSO-inducible manner. The DMSO-induced bindings of EKLF as well as three other proteins, namely, RNA polymerase Ⅱ, acetylated histone H3, and methylated histone H3, were not abolished but significantly lowered in CB3, a MEL-derived cell line with null-expression of p45/NF-E2, an erythroid-enriched factor needed for activation of the mammalian globin loci. Interestingly, binding of EKLF in vivo was also detected in the mouse alpha-like globin locus, at the adult alpha globin promoter and its far upstream regulatory element alpha-MRE （HS26）. This study provides direct evidence for EKLF-binding in vivo at the major regulatory elements of the mouse beta-like globin gene clusters the data also have interesting implications with respect to the role of EKLF-chromatin interaction in mammalian globin gene regulation.

Identification of the metabolite and cytochrome P450 isoforms involved in rat liver microsomal metabolism of TM208

To identify the metabolite and CYP450 isoforms involved in rat liver microsomal metabolism of TM208. The present study investigated the metabolism of TM208 and the effects of selective CYP450 inhibitors on the metabolism of TM208 in rat liver microsomes. Various specific inhibitors of CYP were used to identify the isoforms of CYP involved in the metabolism of TM208. The inhibitor of CYP2D and that of CYP2B had strong inhibitory effects on TM208 metabolism in a concentration-de- pendant manner, the inhibitor of CYP1A had a modest inhibitory effect, and the inhibitor of CYP3A seemed not to have an obvious inhibitory effect on TM208 metabolism. TM208 might mainly be metabolized by CYP2D and CYP2B in rat liver microsomes.

Biotransformation of aesculin by human gut bacteria and identification of its metabolites in rat urine

AIM： To observe the biotransformation process of a Chinese compound, aesculin, by human gut bacteria, and to identify its metabolites in rat urine.METHODS： Representative human gut bacteria were collected from 20 healthy volunteers, and then utilized in vitro to biotransform aesculin under anaerobic conditions. At 0, 2, 4, 8, 12, 16, 24, 48 and 72 h postincubation, 10 mL of culture medium was collected. Metabolites of aesculin were extracted 3 × from rat urine with methanol and analyzed by HPLC. For in vivo metabolite analysis, aesculetin （100 mg/kg） was administered to rats via stomach gavage, rat urine was collected from 6 to 48 h post-administration, and metabolite analysis was performed by LC/ESI-MS and MS/MS in the positive and negative modes.RESULTS： Human gut bacteria could completely convert aesculin into aesculetin in vitro. The biotransformation process occurred from 8 to 24 h post-incubation, with its highest activity was seen from 8 to 12 h. The in vitro process was much slower than the in vivo process. In contrast to the in vitro model, six aesculetin metabolites were identified in rat urine, including 6-hydroxy-7-glucocoumarin（M1）, 6-hydroxy-7-sulf-coumarin （M2）, 6, 7-digluco-coumarin （M3）, 6-glc-7-gluco-coumarin （M4）, 6-O-methyl-7-gluco-coumarin （MS） and 6-O-methyl-7- sulf-coumarin （M6）. Of which, M2 and M6 were novel metabolites.CONCLUSION： Aesculin can be transferred into aesculetin by human gut bacteria and is further modified by the host in vivo. The diverse metabolites of aesculin may explain its pleiotropic pharmaceutical effects.

In Vivo Kinetics and Biodistribution of a Hantaan Virus DNA Vaccine after Intramuscular Injection in Mice

To study the kinetics in vivo of a Hantaan virus DNA vaccine, we constructed a fusion DNA vaccine, pEGFP/S, by cloning the S segment of Hantavirus into the vector, pEGFP-C1, which encodes Green fluorescent protein EGFP. In this report, we provide evidence that pEGFP/S was distributed and persistently expressed for more than 60 days in several organs after inoculation. Our findings suggest that the persistent immune responses induced by a Hantaan virus DNA vaccine are likely due to the plasmid pEGFP/S deposited in vivo, which acts as a booster immunization.

Retinal ganglion cells of high cytochrome oxidase activity in the rat

Retinal ganglion cells in the rat were studied using the heavy metal intensified oytochrome oxidase and horseradish peroxidase histochemieal methods. The results show that a population of large retinal ganglion cells was consistently observed with the eyto3hrome oxidase staining method in retinas of normal rats or rats which received unilateral thalamotomy at birrth. These oytochrome oxidase rich ganglion cells appeared to have large somata, 3-6 primary dendrites and extensive dendritic arbors, and are comparable to ganglion cells labeled by the wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP). However, the morphological details of some of the cells revealed by the cytoahrome oxidase staining method are frequently better than those shown by the HRP histochemieal method. These results suggest that the mit03hondrial enzyme oytoohrome oxidase can be used as a simple but reliable marker for identifying and studying a population of retinal ganglion cells with high metabolie rate in the rat.

Long-term modifications of blood pressure in normotensive and spontane-ously hypertensive rats by gene delivery of rAAV-mediated cytochrome P450 arachidonic acid hydroxylase

Arachidonic acid cytochrome P-450 （CYP） hydroxylase 4A isoforms, including 4A1, 4A2, 4A3 and 4A8 in the rat kidney, catalyze arachidonic acid to produce 19/20-Hydroxyeicosatetraenoic acids （20-HETE）, a biologically active metabolite, which plays an important role in the regulation of blood pressure. However, controversial results have been reported regarding the exact role of 20-HETE on blood pressure. In the present study, we used recombinant adenoassociated viral vector （rAAV） to deliver CYP 4A1 cDNA and antisense 4A1 cDNA into Sprague-Dawley （SD） rats and spontaneously hypertensive rats （SHR）, respectively, to investigate the effects of long-term modifications of blood pressure and the potential for gene therapy of hyperténsion. The mean systolic pressure increased by 14.2±2.5 mm Hg in rAAV.4A 1-treated SD rats and decreased by 13.7±2.2 mm Hg in rAAV.anti4A l-treated SHR rats 5 weeks after the injection compared with controls and these changes in blood pressure were maintained until the experiments ended at 24 weeks. In 4A1 treated animals CYP4A was overexpressed in various tissues, but preferentially in the kidney at both mRNA and protein levels. In anti-4Al-treated SHR, CYP4A mRNA in various tissues was probed, especially in kidneys, but 4A l protein expression was almost completely inhibited. These results suggest that arachidonic acid CYP hydroxylases contribute not only to the maintenance of normal blood pressure but also to the development of hypertension. rAAV-mediated anti4A administration strategy has the potential to be used as targeted gene therapy in human hypertension by blocking expression of CYP 4A in kidneys.

Experimental study on the anticancer effect of curcumin on mouse of S180 in vivo

Objective ：To study curcumin＇s growth inhibitory effects and morphology changes on sarcoma graft＇s of S180 mouse, with further inquiry into the possible mechanisms, Methods： Thirty S180 mouse were randomly assigned into 3 groups ： saline group （blank control group）, Cytoxan group （positive control group） and curcumin group. The tumor inhibitory rates, the index of thymus and spleen,the growth of tumor and the change of pathology-morph, the index of apoptosis cells and morphology changes of apoptosis cells in the different groups were observed. Results： （1） Tumor＇s inhibitory rate in curcumin group and cytoxan group was 68, 32% and 70. 43%, respectively. Compared to blank control group, the 2 groups had significant elevated tumor inhibitory rate （P〈0.01）. （2） Thymus index of curcumin group did not have significant decrease compared to blank control group （P〉0.05）, （3） Under electroscope,curcumin group and positive control group had significant decrease in terms of growth of tumor, degree of infiltration of tumor, the number of nucleus fission, and blood vessels number compared to saline group （P〈0.05）, However, the degree of cell necrosis, the number of splenic segments and macrophage are increased significantly compared to negative group, （4） Accumulative score of apoptosis cell in curcumin group was significantly higher than other two groups（P〈0.05）. Conclusion： Internal organ study and ceil morphology observation show curcumin can effectively inhibit the growth and cause the death of sarcoma graft of S180 mouse without interference with thymus.

Development and Validation of a Liquid Chromatography-Tandem Mass Spectrometry Method for Determination of Artemisinin in Rat Plasma

Artemisinin is a potent anti-malarial drug isolated from traditional Chinese medicinal herb, Artemisia annua. The objective of this study was to develop and validate a sensitive and specific LC-MS/MS method for the determination of artemisinin in rat plasma using amlodipine as Internal Standard. The method consist of a simple liquid-liquid extraction with methyl tertiary butyl ether （MTBE） with subsequent evaporation of the supernatant to dryness followed by the analysis of the reconstituted sample by LC-MS/？vIS with a Z-spray atmospheric pressure ionization （API） interface in the positive ion-multiple reaction monitoring mode to monitor precursor--〉product ions of m/z 282.70--〉m/z 209.0 for artemisinin and m/z 408.9--〉m/z 237.0 for amlodipine respectively. The method was linear （0.999） over the concentration range of 7.8-2000 ng/mL in rat plasma. The intra and inter-day accuracy were measured to be within 94-104.2% and precision （CV） were all less than 5%. The extraction recovery means for internal standard and all the artemisinin concentrations used were between 82-85%.

Effects of Diazepam,Phenobarbital,Propranolol,and Cimetidine on Diazepam Oxidizing Isoenzymes in Rat Liver Microsomes

Isolation and identification of the liver microsomal cytochrome P 450 isoen zymes responsible for the formation of diazepam main metabolites nordiazepam and temazepam in rats were studied. The effects of P 450 inducers and inhibitors on the protein contents in SDS poly acrylamide gel electrophoresis and thin layer chromatography to the corresponding diazepam me tabolizing activities of rat liver microsomes were observed. The P 450 contents were dramatically re duced by ip diazepam, cimetidine or propranolol. Diazepam and propranolol inhibited temazepam formation, high dose of propranolol also inhibited nordiazepam formation. Phenobarbital increased the P 450 contents and induced the production of both nordiazepam and temazepam. It also induced proteins with molecular weight (m) of 51 and 59 kDa in SDS PAGE and those with m ranging from 45 to 55 kDa and from 55 to 65 kDa in TLC. Propranolol inhibited both fractions, especially that of m 55～65 kDa, whereas diazepam tended to inhibit the fraction of 45～55 kDa. The protein of m 51 kDa could be mainly involved in diazepam C3 hydroxylation, whereas those of m 59 kDa could be responsible for the N demethylation of diazepam in rats.

Chemical Composition and in Vitro Antibacterial Activity of the Leaf Essential Oil of Mentha officinalis from Rwanda

The search for new prototype drugs to combat infection is an absolute necessity and in this regard plant essential oils may offer great potential and hope. In this investigation, the essential oil of the leaves ofMentha officinalis grown in Rwanda was extracted by hydrodistillation method and analyzed by gas chromatography （GC） and gas chromatography coupled with mass spectrometry （GC-MS）. The disc diffusion method was used to evaluate in vitro the zone of bacterial growth inhibition at various concentrations of the oil for five bacterial strains： Escherichia coli, Bacillus aureus, Streptococcus lactis, Staphylococcus aureus and Salmonella typhimurium. The results of this study revealed many components among which the major components were menthol （80.79%）, menthone （4.906%）, isomenthone （3.5%）, piperitone （2.56%）, and methyl acetate （2.2%）. After 7 days of incubation on PCA medium, the growth of Escherichia coli, Bacillus aureus, Streptococcus lactis and Staphylococcus aureus was totally inhibited at an average diameter of 19 mm, 32 mm, 50 mm and 30 mm respectively by a medium concentration of 30 μm/disc ofM. officinalis oil. Quite the reverse, this investigation by a bioassay showed that the essential oil ofM. officinalis has no effect on Salmonella typhimurium. The obtained results in the present study indicate the possibility of exploiting the essential oil ofM. officinalis to combat so many infectious human diseases in Rwanda. However, further investigations are required to make the medical exploitation of this plant successful.

Moxibustion activates mast cell degranulation at the ST25 in rats with colitis

AIM: To investigate the effects of moxibustion on the morphology and function of mast cells (MC) at Tianshu (ST25) in rats with trinitro-benzene-sulfonic acid (TNBS)-induced colitis. METHODS: A total of 53 male Sprague-Dawley rats were randomly divided into a normal group and experimental group. In the experimental group, a rat model of TNBS-induced colitis was established, and the rats were then randomly divided into a model group, moxi-bustion group, moxibustion plus disodium cromoglycate (M + DC) group and moxibustion plus normal saline (M+ NS) group. Rats in the moxibustion group received suspended moxibustion at bilateral ST25 for 10 min, once a day for 7 d. Rats in the M + DC and M + NS groups were pretreated with disodium cromoglycate and normal saline at bilateral ST25, respectively, and were then concurrently subjected to the same treatment as rats in the moxibustion group. The hematoxy- lin-eosin staining method was used to observe histology of the colon and the toluidine blue-improved method was used to observe mast cells at ST25 acupoint areas. RESULTS: An improvement in colonic injury in the moxibustion group was observed and the degranulation ratio of MC at ST25 acupoint was markedly higher in the moxibustion group than in the model group (45.91 ± 11.41 vs 32.58 ± 8.28, P < 0.05). After inhibition of degranulation of MC at ST25 by disodium cromoglycate, no improvement in colon tissue injury was observed. CONCLUSION: Moxibustion exerted its effect on healing impaired colonic mucosa in rats with TNBS-induced colitis by increasing the degranulation ratio of local MC, but had little effect on the morphology of MC at ST25 acupoint.

Effect of Yiguanjian decoction on cell differentiation and proliferation in CCl_4-treated mice

AIM： To investigate the cellular mechanisms of action of Yiguanjian （YGJ） decoction in treatment of chronic hepatic injury. METHODS： One group of mice was irradiated, and received enhanced green fluorescent protein （EGFP）- positive bone marrow transplants followed by 13 wk of CCh injection and 6 wk of oral YGJ administration. A second group of Institute for Cancer Research mice was treated with 13 wk of CCI4 injection and 6 wk of oral YGJadministration. Liver function, histological changes in the liver, and Hyp content were analyzed. The expres- sion of m-smooth muscle actin （α-SMA）, F4/80, albumin （AIb）, EGFP, mitogen-activated protein kinase-2 （PKM2）, Ki-67, fetoprotein （AFP）, monocyte chemotaxis pro- tein-1 and CC chemokine receptor 2 were assayed. RESULTS： As hepatic damage progressed, EGFP-po- sitive marrow cells migrated into the liver and were mainly distributed along the fibrous septa. They showed a conspicuous coexpression of EGFP with ^-SMA and F4/80 but no coexpression with AIb. Moreover, the expression of PKM2, AFP and Ki-67 was enhanced dy- namically and steadily over the course of liver injury. YGJ abrogated the increases in the number of bone marrow-derived fibrogenic cells in the liver, inhibited expression of both progenitor and mature hepatocyte markers, and reduced fibrogenesis. CONCLUSION： YGJ decoction improves liver fibrosis by inhibiting the migration of bone marrow cells into the liver as well as inhibiting their differentiation and suppressing the proliferation of both progenitors and hepatocytes in the injured liver.