Chromatin arrangements in intact interphase nuclei examined by laser confocal microscopy

Using a laser confocal microscope, chromatin arrangements in intact interphase nuclei were investigated in four plant species. Chromosomes in these plants have specific segments that can be stained with the fluorescent dye chromomycin A₃ (CMA). We stained centromeres inHordeum vulgare, sub-telomeric regions inSecale cereale, satellites inChrysanthemum multicore, and the satellites and the short arms of chromosomes with satellites inHemerocallis middendorfii. The following points were shown: (1) In mitotic interphase nuclei, the centromere and the telomeres of both arms touched the nuclear membrane and had evident polarity. Some CMA-bodies in sub-telomeric regions do not contact the nuclear membrane. (2) Differentiated nuclei had a non-random construction. Polarity of chromosomes is maintained, however, the chromosomes are far apart from the nuclear membrane. (3) Associations in sub-telomeric regions in the interphase nuclei ofSecale cereale were probably due to the association of heterochromatic regions with identical repeated sequences rather than telomere associlations. (4) In interphase nuclei ofChrysanthemum multicore, satellites fused during interphase.     

Biophoton emission

The phenomenon of ultraweak photon emission from living systems was further investigated in order to elucidate the physical properties of this radiation and its possible source. We obtained evidence that the light has a high degree of coherence because of (1) its photon count statistics, (2) its spectral distribution, (3) its decay behavior after exposure to light illumination, and (4) its transparency through optically thick materials. Moroever, DNA is apparently at least an important source, since conformational changes induced with ethidium bromide in vivo are clearly reflected by changes of the photon emission of cells. The physical properties of the radiation are described, taking DNA as an exciplex laser system, where a stable state can be reached far from thermal equilibrium at threshold.     

Effects of Hydroclytic Enzymes on Plant-parasitic Nematodes

Proteases, lipase, and chitinase killed Tylenchorhynchus dubius in vitro and in soil. Tylenchorhynchus dubius was more susceptible to the enzymes than Pratylenchus penetrans. Papain was the most effective protease, and other enzymes were less effective. Heating enzymes to 80 C for 10 min greatly reduced nematicidal effectiveness. Scanning electron micrographs showed that papain and chitinase produced structural changes in the cuticle of T. dubius. Lipase removed a thin outer layer. Papain removed material filling the striata, or furrow, between the horizontal bands. When added to soil, chitinase, lipase, collagenase, and proteases (papain and bromelain) decreased motility of T. dubius populations up to 75%. Bromelain was the most active in soil against T. dubius, and collagenase was the most active in soil against P. penetrans.     

A study of the microtriches of adult Echinococcus granulosus by scanning electron microscopy

Thompson R. C. A., Houghton A. and Zaman V. 1982. A study of the microtriches of adult Echinococcus granulosus by scanning electron microscopy. International Journal for Parasitology12: 579–583. The microtriches in different regions of the scolex and strobila of sexually mature Echinococcus granulosus were examined using the scanning electron microscope. E. granulosus was found to possess two morphologically distinct types of microthrix. A cylindrical, slender filamentous type of microthrix which appeared to be flexible was restricted to the scolex. On the strobila, the only type of microthrix observed was a flattened blade-like form which appeared to be rigid for most of its length. The occurrence of two distinct types of microthrix in separate regions of the body of E. granulosus suggests that they may be involved in different functional activities.     

The sub-membrane reticulum of the human erythrocyte: A scanning electron microscope study

A web-like reticulum underlying the human erythrocyte membrane was studied at a resolution of 5–10 nm by means of a scanning electron microscope. The network was visualized in isolated membranes (ghosts) torn open to reveal their interior space and in residues derived from ghosts extracted with Triton X-100. It formed a continuous (rather than patchy) cover over the entire cytoplasmic surface, except where lifted off or torn away. Filaments (5–40 nm in diameter), annular figures (40–60 nm in diameter), and nodes (30–100 nm in diameter) were prominent in different networks. The dimensions of the filaments and the interstices in the reticulum varied with conditions, suggesting that the network has elastic properties. This reticulum is probably related to the erythrocyte membrane proteins spectrin and actin.     

Five New Species of Henneguya (Protozoa: Myxosporida) from Ictalurid Fishes*

SYNOPSIS. Four new species of Henneguya (myxosporidan) are described from Ictalurus punctatus Rafinesque (channel catfish). They are as follows: Henneguya postexilis sp. n. and Henneguya longicauda sp. n. from the gills; Henneguya adiposa sp. n. from the adipose fin; and Henneguya diversis sp. n. from the liver, kidney, connective tissue of muscles and fins, and tumor-like external growths. Henneguya pellis sp. n. is described from the dermis of Ictalurus furcatus (LeSueur) (blue catfish). The development stages of all described species are discussed. Henneguya exilis Kudo was found on the gills of one I. punctatus; notes on its spore characteristics are presented.     

中枢神经细胞的高尔基复合体ACP活性分布的电镜观察

本文采用电镜金属盐法—酸性磷酸酶(ACP)细胞化学技术,用30mmol/L pipes缓冲液配制低浓度戊二醛进行固定。对成年大鼠的大脑大锥体细胞,小脑浦肯野氏细胞,脊髓前角运动细胞的高尔基复合体的ACP活性进行了实验研究和探讨。结果发现ACP活性分布在高尔基复合体的部份转移泡、浓缩泡及GERL部位。高尔基复合体呈ACP阳性反应,并显示出多种形态。     

口腔各种产黑色素类杆菌外膜结构的电镜观察

本文对从根管中分离的产黑色素类杆菌群的部分菌株:牙髓类杆菌、牙龈类杆菌、中间型类杆菌、产黑色素类杆菌的表面结构进行了电镜观察。观察发现牙髓类杆菌、牙龈类杆菌表面有放射状排列的菌毛样结构;牙龈类杆菌表面有荚膜;多数细菌的细胞膜外有多个小泡状结构;这些结构可能在细菌吸附于组织的过程中起着重要的作用。     

氦氖激光对绵羊精清中酶活性效应的研究

本文研究结果表明低剂量的氦氖激光可以提高绵羊精清中GOT和LDH酶的活性,并对其机制作了初步的探讨。     

Hexokinase Levels in Discrete Regions of Rat Brain: Evaluation by Quantitative Immuno fluoresence Using Interactive Laser Cytometry and Comparison with Basal Rates of Glucose Utilization

Relative levels of hexokinase (ATP:D-hexose 6-phosphotransferase, EC 2.7.1.1) have been determined in 16 discrete regions of adult rat brain by a quantitative immunofluorescence method. The distribution of immunofluorescence in brain sections was determined by interactive laser cytometry and related to hexokinase content by comparison with standard sections containing known amounts of the enzyme. In many of these regions, referred to here as group I regions, hexokinase content was correlated with previously reported basal rates of glucose utilization. However, several regions (group II regions) in which hexokinase content exceeded that expected from basal rates of glucose utilization were also detected. Compared with the corresponding regions from albino rat brain, higher hexokinase levels were found in the dorsal and ventral lateral geniculate (group I regions) of pigmented Norway rats, a result reflecting previously reported increased glucose utilization by these regions in pigmented rats. There was no difference in hexokinase levels in the superior colliculus, a group II structure, from albino and pigmented rats, a finding implying that a reported increase in rate of glucose utilization in the superior colliculus of pigmented rats is effected without an increase in hexokinase content. It is suggested that group II regions may be adapted to sustain increases in rates of glucose utilization that are, relative to basal rates, considerably greater than those experienced by group I regions.