Response of Three Arbuscular Mycorrhizal Fungi to Simulated Acid Rain and Aluminium Stress

Simulated acid rain (SAR) combined with higher concentration of aluminium (SAR+Al) influenced the ecophysiology of three arbuscular mycorrhizal fungi (AMF) in both the germination and symbiotic phases of their life cycle. Acaulospora tuberculata, an isolate from the soil with low pH, exhibited a higher tolerance to environmental stress as compared to Glomus mosseae and G. fistulosum. This higher tolerance may be related to the edaphic conditions of soil of the isolate origin. The histochemical staining of the alkaline phosphatase and NADH-diaphorase activities in the extraradical mycelium (ERM) of the AMF proved to be more sensitive indication of negative effects of the SAR or SAR+Al stress compared to commonly measured parameters of the AMF such as mycorrhizal colonisation or growth of the ERM. This revised version was published online in July 2006 with corrections to the Cover Date.     

Identification and Pattern of Primary Sensory Cells in the Body Wall Epithelium of the Tubificid Worm, Limnodrilus hoffmeisteri

This study compares the effectiveness of two examination methods suitable for morphological observations, scanning electron microscopy (SEM) and light microscopic NADH-diaphorase (NADP-d) histochemistry, to identify location and distribution pattern of primary sensory cells situated in the body wall epithelium of Limnodrilus hofmeisteri. SEM observations revealed that grouped sensory cells forming two distinct types of sensillas (or sense organs) are scattered over the body surface. The easily identifiable first type (ciliated sensilla) contains numerous penetrative ciliate sensory cells while no ciliate sensory cells were seen in the second type (sensory bud). NADH-d staining proved to be a suitable method to identify both structures further staining solitary sensory cells, and certain sensory fibres that could not be visualised by SEM preparations. Our results show that NADH-d staining, as a histochemical marker of primary sensory cells, is a suitable and effective method to reveal their morphology and distribution pattern in whole mount preparations in the smallest detail, suggesting that the application of this relatively simple and cheap method may contribute to understand the basic organisation and evolution of the peripheral sensory structures of oligochaetes.     

Morphological changes during ontogeny of the canine proximal colon

The development of the canine proximal colon from the completion of organogenesis through 43 days after birth was studied using light microscopy, immunofluorescence and electron microscopy. During this period the tunica muscularis increased in thickness from 42±6 m in animals midway through the gestation period to 317±29 m in animals 25–30 days old. This increase in thickness resulted from an increase in the number and size of smooth muscle cells in the circular and longitudinal muscle layers. The cross-sectional thickness of the circular muscle layer increased from 10±2 smooth muscle cells midway through the gestation period to 92±7 cells in animals 25–30 days old. The longitudinal layer increased in thickness from 1.5±1 cells in animals midway through the gestation period to 44±2 cells in animals 25–30 days old. Smooth muscle cells from both layers also increased in diameter and length. Ultrastructural and immunohistochemical studies suggested that many of the smooth muscle cells were undergoing development throughout the fetal period. Midway through the gestation period, the circular layer was positive for desmin-like immunoreactivity (D-LI), while both the circular and longitudinal layers were positive for vimentinlike immunoreactivity (V-LI). By birth, V-LI was suppressed in the circular and longitudinal layers, and both layers expressed D-LI. The enteric nervous system was already established midway through the gestation period, and submucosal and myenteric ganglia could be identified, although the chemical coding and mature morphology of neurons were incomplete. NADPH-diaphorase-positive neurons, indicating the expression of nitric oxide synthase, developed by the time of birth. Interstitial cells of Cajal (IC) could not clearly be identified midway through gestation, however, potential precursors to ICs were observed. Several classes of ICs were identifiable at birth.     

Enhancement of Enzyme-Catalyzed Production of Reactive Oxygen Species by Suspensions of “Crocidolite” Asbestos Fibres

Ethylene release from methylthio-ketobutyric acid is an indicator for activated oxygen species of the OH '-radical type. Xanthine oxidase plus xanthine or diaphorase in the presence of NADH and j uglone produce OH'-type oxy-radicals. The production of reactive oxygen species in these enzymatic systems is enhanced by “crocidolite” asbestos fibres.     

Enhancement of Enzyme-Catalyzed Production of Reactive Oxygen Species by Suspensions of “Crocidolite” Asbestos Fibres

Ethylene release from methylthio-ketobutyric acid is an indicator for activated oxygen species of the OH '-radical type. Xanthine oxidase plus xanthine or diaphorase in the presence of NADH and j uglone produce OH'-type oxy-radicals. The production of reactive oxygen species in these enzymatic systems is enhanced by “crocidolite” asbestos fibres.     

人小肠粘膜内神经元的组织学与组织化学观察

一般认为,胃肠道粘膜内不存在神经元,粘膜神经丛仅由神经纤维组成。本文使用常规组织学方法和 NADH 黄递酶组化法证明在人小肠粘膜内可见到单个的神经元或由2～5个神经元组成的神经节。神经元胞体大小不等,形态多样,除梭形、卵圆形和不规则形外,还有呈扁平形的。粘膜内神经元多数位于固有层内,常紧贴粘膜肌;粘膜肌层内也可见到神经元。我们认为,小肠粘膜内神经元是肠神经系中粘膜神经丛的一部分。     

Homozygotie et consanguinité au locus de la diaphorase à NADH dans Différences troupes du babouin de guinée Papio papio

Variants of NADH-diaphorase have been studied among several groups of natural populations of Papio papio from Senegal. At this locus homozygosity is increased and the level of inbreeding is very high (F = 0.67). Our results parallel those on other Papio species and it seems plausible to assume that group organization influencnes these parameters.     

Further studies on sheep polymorphic erythrocyte diaphorase

Starch gel electrophoresis of sheep hemolysates revealed anodically faster, poly. morphic NADH/NADPH diaphorase (Dial) and slower NADH diaphorase (Dia2). Frequencies of alleles Dia1 F and Dia1 S for six sheep breeds in Czechoslovakia are given and efficacy for parentage control is discussed. A heterogeneity in Dia2 is caused by a prolonged storage of samples.