Differential interleukin 1 elaboration by unfractionated and density fractionated human alveolar macrophages and blood monocytes: relationship to cell maturity

The elaboration of interleukin 1 (IL 1) by mononuclear phagocytes is important in the regulation of human inflammatory and fibrotic reactions. Mononuclear phagocytes are morphologically and functionally heterogeneous cells. To further understand the processes controlling inflammation and fibrosis, in particular that in the human lung, we studied the elaboration of IL 1 by unfractionated and density-fractionated human alveolar macrophages and blood monocytes. Stimulated blood monocytes elaborated more IL 1 than stimulated alveolar macrophages. In addition, denser alveolar macrophages and blood monocytes elaborated more IL 1 than less dense alveolar macrophages and monocytes. Lastly, as monocytes matured in vitro, they lost their ability to elaborate IL 1 and became less dense. Thus, there is variability between and within mononuclear phagocyte cell populations in their ability to elaborate IL 1. These differences may result in part from differences in cell maturation.     

Isolation of specific antigens from Angiostrongylus cantonensis. 1. Preparative flatbed isoelectric focusing

Electrophoresis on SDS gel and analytical isoelectric focusing showed that a crude extract of Angiostrongylus cantonensis consisted of at least 40 protein components with molecular weights ranging from 13 000-70 000 and isoelectric points of pI values ranging from 3.7-10.0. Crossed-immunoelectrophoresis with a hyperimmune antiserum to A. cantonensis showed at least 40 different antigenic components in the crude worm extract which were cross-reactive with those of Ascaris suum, Metastrongylus apri and Toxocara canis. Using preparative isoelectric focusing, the somatic worm preparation was divided into 13 equal fractions, of which 3, 4 and 5, with pI values of 3.7, 4.0 and 4.45 respectively, were later shown by immunoelectrophoretic techniques and enzyme-linked immunosorbent assay to contain antigens specific to A. cantonensis.     

高等植物叶片中的硝酸还原酶活性稳定因子

从小麦、油菜、浮萍、番茄、烟草的叶片中分离得到NR-SF。不同植物材料中NR及NR-SF能起交叉反应;不同NR-SF影响NR酶动力学性质相同;不同NR-SF的凝胶电泳谱带显示蛋白和糖蛋白性质。NR-SF广泛存在于植物细胞中。     

土壤中含EB病毒诱导物的检测

从广西壮族自治区梧州市、苍梧县、罗城县和北京市收集的土壤标本中发现有EB病毒诱导物。梧州市和苍梧县沿公路和江河两旁桐油树下的土壤标本,对EB病毒早期抗原诱导的阳性率为40～58％。在其他大戟科植物下的土壤标本中,也发现有EB病毒诱导物。对桐油树下土壤中EB病毒诱导物与鼻咽癌发生的可能关系进行了讨论。     

Spontaneous Mutations Modifying the Activity of Alcohol Dehydrogenase (Adh) in DROSOPHILA MELANOGASTER

In a marked-inversion balanced lethal system of the second chromosome of Drosophila melanogaster, mutations were accumulated under minimum pressure of natural selection in 1000 individual lines that originated essentially from two individuals. After about 300 generations, the specific activities of alcohol dehydrogenase of 69 randomly selected individual lines were measured with replications using four replicated vials (on 2 days—two replications per day) by observing the reduction of NAD⁺ to NADH at 340 nm. Total soluble protein as the basis of standardization of enzyme activity was measured by the Lowry method for each vial. A control experiment was made immediately after the establishment of 20 individual lines from a single genotype. A significant increase in genetic variance was observed among the mutation-accumulating lines but was not detected in the control experiment. The statistical analysis of the data on the basis of the one-band/one-gene hypothesis suggests that many mutations controlling the activity of alcohol dehydrogenase occurred in regions different from the alcohol dehydrogenase locus itself, mainly in the noncoding DNA. Furthermore, it is suggested that transposon-like elements are related to the induction of these changes in alcohol dehydrogenase specific activities. Additional experimental evidence supporting this conclusion is also given.     

广谱肾综合征出血热病毒单克隆抗体的A35的生物学性状

具有中和及血凝抑制活性的、能和世界各地分离到的肾综合征出血热病毒(HFRSV)发生反应的、广谱的单克隆抗体(McAb),对HFRSV的诊断和分子生物学研究都有重要意义。 本文着重比较了HFRSV McAbA5、A19、A25-1、A25-7和A35的生物学性状,并观察了对感染动物的实验治疗效果。     

表面活性剂和Ca~(++)对大麦根质膜透性的作用

阳离子型表面活性剂(CTMA)以低于CMC的浓度、非离子型表面活性剂(Triton-X-100)以高于CMC的浓度引起大麦离体根K~+及可溶性糖的外流,并有浓度效应。5℃时表面活性剂引起溶质外流,CTMA预处理10 min后,Ca~(++)无抑制作用。Ca~(++)与 Triton-X-100同时处理大麦根促进溶质外流。Mg~(++)、Mn~(++)对CTMA及Triton-X-100引起溶质外流的效应与Ca~(++)的相类似,但不如Ca~(++)有效。     

三七中达马烷型皂甙的热不稳定性及酸水解产物

前人已证明人参和三七中富含的达马烷型人参皂甙在通常酸性水解下甙元即发生变化,而在弱酸(如50％醋酸,0.1N盐酸)条件下则形成次级皂甙。本文报道人参甙(ginseno-sides)和三七甙(notoginsenosides)的水溶液在水浴上加热亦分别形成相应的C-20位去糖基的次级皂甙。联系到人参和三七均有在蒸煮加工后C-20位去糖基皂甙收率增大的趋势,似可认为人参和三七中的这类皂甙有相当一部分是在生药的加工泡制以及提取过程中形成的次级皂甙,而不一定是植物体的原生成分。将人参甙Rb_1单体以酸水解,不仅得到主产物人参二醇(3),还分离到异去氢原人参二醇(5)、达马烷-20(22)-烯-3β,12β,26-三醇(6)、20(R)-达马烷-3β,12β,20,25-四醇(7)以及20(S)-和20(R)-原人参二醇(1、2)的混合物,从而认为这些微量成分与人参二醇一样均为达马烷型人参皂甙在酸性水解条件下C-20位糖基断裂后由真甙元的侧链转化形成的工作产物。     

The bulk rheology of close-packed red blood cells in shear flow

A theoretical analysis is made of the dynamical behavior and bulk rheology of close-packed red blood cell suspensions subjected to simple shear flow. The model for the polyhedral cell shapes and tank-treading membrane motion developed in the companion paper (1) is used. The flow in the thin lubricating plasma layers between cells is analyzed taking into account the mechanical properties of the membrane at the corner regions of sharp membrane curvature. This leads to predictions for the apparent viscosity as a function of hematocrit and shear rate. Good agreement with experimental results is obtained at moderate and high shear rates (above 20 s-1). At lower shear rates, a rapid rise in apparent viscosity has been found experimentally, and the mechanisms leading to this behavior are examined.     

Formation and properties of cell-size lipid bilayer vesicles

Hydration of single or mixed phospholipids or lipid protein mixtures at low ionic strength results in the formation of a population of large, solvent free, single bilayer vesicles with included volumes of up to 300 microliters/mumol lipid. Their size ranges from 0.1 to 300 microns and they can be sorted out according to size by centrifugation. When formed in distilled water their internal solution has a conductivity of 20-50 microseconds/cm-1, an osmolarity of 0.5-5 mOsM, and a density of 1.0005-1.001. The osmotic pressure produced by the internal solutes cause a surface stress of 25 dyn/cm for a 20-microns vesicle. Their elastic constant ranges from 75-150 dyn/cm. During formation they can internalize particles such as latex beads or cell nuclei. They can be impaled with microelectrodes, or patch clamped. They can also be sealed to a small Vaseline-treated hole in a thin partition between two aqueous compartments. Sealing occurs in two stages. In the first stage sealing resistance is similar to that seen with patch-clamp pipettes. In the second stage, a much tighter seal is obtained. After sealing, the smaller portion of the sealed vesicle can be selectively broken by an electric shock leaving a single membrane across the hole. The capacitance and resistance of such membranes, in the presence of 10 mM NaCl, are approximately 0.7 microF/cm2 and 10(8) omega cm2 for pure lipid vesicles. Gramicidin increases the membrane conductance and monazomycin induces voltage-dependent gating thus providing further evidence that the vesicles are bounded by a single bilayer.