采用IL－6cDNA控针检测人IL－6基因表达

采用缺口平移技术对ＩＬ—６ｃＤＮＡ进行了生物素和同位素标记，证明两种标记的ＩＬ－６ｃＤＮＡ（３０ｎｇ／ｍｌ）均可检出低至５ｐｇ的同源ＤＮＡ，而模拟探针（５００μｇ／ｍｌ）对高达１００ｎｇ的同源序列无此反应。应用ＩＬ－６ｃＤＮＡ对富含ＩＬ－６ｍＲＮＡ的标本进行斑点杂交或Ｎｏｒｔｈｅｒｎ杂交，证明人参三醇皂甙促进了淋巴细胞ＩＬ—６基因表达（４倍），人胎脾单个核细胞、人胎脑组织匀浆和人胎胰岛细胞内均含有高浓度ＩＬ—６ｍＲＮＡ。     

A case of 46,XX,r(X) (p1q1) diagnosed by in situ hybridization

A small marker chromosome was identified as an X-derived ring chromosome by in situ hybridization with a biotinylated X-chromosome specific a-satellite DNA probe. This procedure clearly determined the chromosomal origin of the marker chromosome, which had been impossible to define by conventional cytogenetic techniques including high resolution banding.     

Imaging neuromuscular junctions by confocal fluorescence microscopy: individual endplates seen in whole muscles with vital intracellular staining of the nerve terminals

The mammalian neuromuscular junction has been extensively studied by different methods to understand better the biological aspects of its normal development, ageing and pathological conditions, such as disorders of neuromuscular transmission. In the present report, a new technique is described that combines confocal microscopy with the use of a vital nerve terminal dye (4-Di-2-ASP) and rhodamine-alpha-bungarotoxin to stain postsynaptic acetylcholine receptors in the same endplate. Nerve terminals in the sternomastoid muscles of living adult mice were stained with 4-Di-2-ASP, which labels intracellular compartments of the nerve terminal containing mitochondria. Slides of these muscles were viewed by confocal microscopy and images were stored on magnetic optical discs. This procedure was compatible with subsequent acetylcholine receptor staining with rhodamine-α-bungarotoxin and observation under the confocal microscope. Classical features of the adult neuromuscular junction were displayed, such as the branched-pattern distribution of the nerve terminals and receptors and their complete colocalisation. In addition, nerve fibres from intramuscular nerve branches with their neighbouring cells, nuclei and muscle fibre striations could also be visualised. We conclude that the present technique can complement existing methods of investigation of nerve terminal anatomy and pathology, particularly where preservation of 3-dimensional relationships is required and intracellular disturbances involving mitochondrial organisation, such as ageing or other degenerative disorders, may be present.     

Descending pathways to the spinal cord in the himé salmon (landlocked red salmon, Oncorhynchus nerka)

Distribution and morphology of the cells of origin of the descending spinal pathways and their axonal courses were studied in the himé salmon, using retrograde labelling with cobaltic lysine and horseradish peroxidase (HRP). Following application of the tracers to the cut end of the spinal cord or injection of the tracers at the 10th to 15th spinal segment, neurons mainly labelled via the axons of passage were distributed in the mesencephalon and the rhombencephalon. Mesencephalic cell groups consisted of the nucleus pretectalis, the nucleus fasciculi longitudinalis medialis, and the nucleus ruber. The former two cell groups sent their axons to the fasciculus longitudinalis medialis. The axons of the nucleus ruber formed a separate loose bundle, the "tractus rubrospinalis." The rhombencephalic cell groups consisted of the rhombencephalic reticular formation, the Mauthner cells (one cell for each side), and the octavolateral area. The rhombencephalic reticular formation could be further subdivided into the nucleus reticularis superior, nucleus reticularis medius, and nucleus reticularis inferior. The axons of these cell groups joined the fasciculus longitudinalis medialis and the "tractus bulbospinalis." The Mauthner cell had two main gigantic dendrites, and its giant axons formed a conspicuous fiber of Mauthner throughout the rhombencephalon down to the spinal cord. The octavolateral area could be subdivided into the nucleus vestibularis magnocellularis, nucleus tangentialis, nucleus vestibularis descendens and nucleus intermedius. The axons of the nucleus vestibularis magnocellularis and nucleus intermedius entered the fasciculus longitudinalis medialis and/or the tractus bulbospinalis. Those of the nucleus vestibularis descendens and nucleus tangentialis formed the "tractus vestibulospinalis". The descending spinal pathways of the himé salmon were compared with those of other fishes and other vertebrates. The significance of these descending spinal pathways in the control of locomotion and sexual behavior is also discussed.     

Assessing the Effectiveness of Front of Pack Labels: Findings from an Online Randomised-Controlled Experiment in a Representative British Sample

Front of pack food labels (FOPLs) provide accessible nutritional information to guide consumer choice. Using an online experiment with a large representative British sample, we aimed to examine whether FOPLs improve participants’ ability to identify the healthiness of foods and drinks. The primary aim was to compare ability to rank between FOPL groups and a no label control. Adults (≥18 years), recruited from the NatCen panel, were randomised to one of five experimental groups (Multiple Traffic Light, MTL; Nutri-Score, N-S; Warning Label, WL; Positive Choice tick, PC; no label control). Stratification variables were year of recruitment to panel, sex, age, government office region, and household income. Packaging images were created for three versions, varying in healthiness, of six food and drink products (pizza, drinks, cakes, crisps, yoghurts, breakfast cereals). Participants were asked to rank the three product images in order of healthiness. Ranking was completed on a single occasion and comprised a baseline measure (with no FOPL), and a follow-up measure including the FOPL as per each participant’s experimental group. The primary outcome was the ability to accurately rank product healthiness (all products ranked correctly vs. any incorrect). In 2020, 4504 participants had complete data and were included in the analysis. The probability of correct ranking at follow-up, and improving between baseline and follow-up, was significantly greater across all products for the N-S, MTL and WL groups, compared to control. This was seen for only some of the products for the PC group. The largest effects were seen for N-S, followed by MTL. These analyses were adjusted for stratification variables, ethnicity, education, household composition, food shopping responsibility, and current FOPL use. Exploratory analyses showed a tendency for participants with higher compared to lower education to rank products more accurately. Conclusions: All FOPLs were effective at improving participants’ ability to correctly rank products according to healthiness in this large representative British sample, with the largest effects seen for N-S, followed by MTL.     

核素标记混合抗体瘤内注射治疗大肠癌的实验研究

目的:为临床应用混合抗体进行放射免疫治疗提供实验依据。方法:在裸鼠荷人大肠癌Lovo移植瘤生长至1cm时,瘤内分别或同时注射~(131)I标记的抗CL_3单克隆抗体(~(131)I-CL_3)和~(131)I标记抗FERR单克隆抗体T_9(~(131)I-T_9),治疗后行SPECT显像观察标记抗体在肿瘤内的浓聚,并进行疗效观察。结果:我们发现两种抗体混合治疗组疗效明显好于单独治疗组,抗体在肿瘤内的浓聚也大于单独应用。结论:多种抗体混合应用瘤内注射放射免疫治疗可增加标记抗体在肿瘤内的浓聚,并能提高放射免疫治疗的疗效。     

Exploring the main and moderating effects of individual-level characteristics on consumer responses to sugar taxes and front-of-pack nutrition labels in an experimental marketplace

InterventionThis study examined whether the impacts of sugar taxes and front-of-pack (FOP) nutrition labels differ across socio-demographic subgroups.Research questionWhat are the main and moderating effects of individual-level characteristics on the nutrient content of participants’ purchases in response to varying taxation levels and FOP labels?MethodsData from an experimental marketplace were analyzed. A sample of 3584 Canadians aged 13 years and older received $5 to purchase an item from a selection of 20 beverages and 20 snack foods. Participants were shown products with one of five FOP labels and completed eight within-subject purchasing tasks with different tax conditions. Linear mixed models were used to estimate the main and moderating effects of 11 individual-level variables on the sugars, sodium, saturated fats, and calorie content of participants’ purchases.ResultsParticipants who were younger, male, and more frequent consumers of sugary drinks purchased products containing more sugars, sodium, saturated fats, and calories. Sex and age moderated the relationship between tax condition and sugars or calories purchased: female participants were more responsive than males to a tax that included fruit juice, and younger participants were more responsive to all sugar tax conditions than older participants. Reported thirst and education level also moderated the relationship between tax condition and calories purchased. No individual-level characteristics moderated the effects of FOP labels.ConclusionA small proportion (7 of 176) of the moderating effects tested in this study were significant. Sugar taxes and FOP labelling policies may therefore produce similar effects across key socio-demographic groups.Supplementary InformationThe online version contains supplementary material available at 10.17269/s41997-021-00475-x.     

Striatal NPY-Containing Neurons Receive GABAergic Afferents and may also Contain GABA: An Electron Microscopic Study in the Rat

Dual labelling methods were applied to localize simultaneously neuropeptide Y (NPY) and glutamate decarboxylase (GAD) immunoreactivities on ultrathin sections of the rat caudate-putamen (CP). By means of a double peroxidase-anti-peroxidase technique, using 3,3'-diaminobenzidine and benzidine dihydrochloride as chromogens in animals with no colchicine pretreatment, GAD immunoreactivity was found to be present in terminals only whereas NPY immunoreactivity was detected in neurons displaying the features of aspiny type cells and processes. With this approach, we observed numerous synaptic associations of the symmetrical type between GAD-immunoreactive (-Ir) axonal boutons and NPY-Ir cell bodies and dendrites. By combining immunoperoxidase and radioimmunocytochemical labelling in animals pretreated with colchicine, NPY was again detected in a single population of aspiny type neurons whereas GAD immunoreactivity was observed in neurons which could be classified as aspiny and spiny on the basis of their ultrastructural characteristics. All the cells of the aspiny type displaying clear-cut NPY immunoreactivity were also found to be GAD-positive. Some other neurons of both the aspiny and the spiny type were found to be immunoreactive to GAD alone. GAD/NPY dually labelled terminals were also observed and some axo-axonic appositions between GAD- and NPY-Ir terminals were also detected. All in all, these data show that NPY aspiny type neurons of the rat CP receive GABAergic afferents and provide morphological support for two hypotheses: that NPY is co-localized with GABA in some cell bodies, dendrites and axons, and that presynaptic interactions may occur between NPY and GABAergic neuronal systems.     

Influence of Fluorescent Labelling of Polystyrene Particles on Phagocytic Uptake,Surface Hydrophobicity,and Plasma Protein Adsorption

Purpose. To investigate the influence of fluorescent labelling of polystyrene particles on phagocytic uptake, surface hydrophobicity and protein adsorption. Methods. Phagocytic uptake was analysed using chemiluminescence. Hydrophobicity was quantified by adsorption measurements of a hydrophobic dye. Protein adsorption was evaluated by two-dimensional electrophoresis. Results. Commercially available fluorescently labelled particles showed marked differences when compared to unlabelled particles: phagocytic uptake and surface hydrophobicity of labelled particles were diminished. Also the plasma protein adsorption pattern was found to be different from the unlabelled particles: for example, the amount of fibrinogen adsorbed was strongly reduced on the labelled particles. On the other hand, some unknown proteins could be detected on the fluorescently marked particles. In contrast, plain polystyrene particles and labelled ones could be successfully synthesised by Paulke which did not show any considerable differences in phagocytic uptake, surface hydrophobicity and protein adsorption. Polysorbate 20 added as stabilizer to particle suspensions led to completely different behaviour of the particles: the particles showed altered protein adsorption patterns, dominated by immunoglobulins and especially by apolipoproteins. Furthermore, these particles were not phagocytized at all. Conclusions. Surface hydrophobicity and phagocytic uptake in vitro as well as the interactions with plasma proteins of commercially available polystyrene particles were strongly affected by fluorescent labelling. Particles synthesised by Paulke remained unchanged after labelling. The results show the importance of thorough surface characterization for using particles in test systems in vitro and in vivo.     

Labelling of leucocytes with colloidal tech netium-99m-SnF2: an investigation of the labelling process by autoradiography

Autoradiography of smears and frozen sections of labelled cell suspensions was used to study the distribution of radioactivity in and among blood cells labelled in either whole blood or leucocyte-rich plasma (LRP) with technetium-99m-SnF₂ colloid. The tracer proved selective for neutrophils: the labelling probability (relative to that for erythrocytes) for each cell type in LRP (mean of five samples) was: neutrophils, 9.4; lymphocytes, 3.7; monocytes, 3.0; eosinophils 1.4; erythrocytes, 1.0. When labelling was carried out in whole blood (five samples), 74.5%±8.3% of the cell-bound radioactivity was bound to erythrocytes, 13.6%±6.5% to neutrophils, and 11.9%±2.1% to lymphocytes, whereas in LRP (in which the leucocytes were only slightly out-numbered by erythrocytes), 76.5%±14.9% of radioactivity was neutrophil bound. Labelled cells in smear autoradiographs exhibited two distinct silver grain patterns, diffuse, consistent with an intracellular radioactive particle (in neutrophils), and focal, consistent with a cell surface-adhering particle in direct contact with the emulsion (in other leucocyte types and erythrocytes). The phagocytic inhibitor cytochalasin B neither reduced the proportion of labelled neutrophils nor altered the labelling pattern. Neutrophils were able to scavenge radioactivity from the surface of erythrocytes. It is concluded that neutrophils bind^99mTc-SnF₂ intracellularly by phagocytosis, with high affinity; other cells become labelled at the cell surface reversibly and with lower affinity. This selectivity is high enough to permit predominantly leucocyte labelling in LRP but not in whole blood.