The effect of age on the ultrastructure of the mid-gut cells of the hymenopteran Nasonia vitripennis (Walk.) (Hymenoptera, Pteromalidae)

The ultrastructure of the mid-gut cells of aged female Nasonia vitripennis is described. The mid-gut is a shrunken and distorted organ in the aged animal. The individual cells are highly disorganised and the organelle components are altered. The small lipid droplets formed in the apical cell region do not coalesce to form the large central lipid inclusions characteristic of the young animal. The rough endoplasmic reticulum is reduced and some of the mitochondria enlarge. The mid- and apical cell regions also contain large numbers of cytolysosomes. The basal cell region is essentially unchanged, but the channels formed by the infolded basal plasma membranes are dilated. The changes observed are discussed in relation to previous observations on other insect species.     

Fucosterol-24,28-epoxide, an intermediate in the oxidative biodegredation of fucosterol to cholesterol by the cricket (Locusta migratoria (R. and F.)

beta-Sitosterol 1 is metabolised to cholesterol 5 by phytophagous insects. It has been previously shown that fucosterol-24,28 epoxide 3 is transformed into 5 in Locusta migratoria, desmosterol 4 being an intermediate. It is now established that locusts transform [3-3H]fucosterol propionate into the corresponding labelled epoxide 3, recovered as such or as an oxazoline derivative 11.     

The effect of an extract of sea buckthorn (Hippophae rhamnoides L.) on the healing of experimental skin wounds in rats

The effect exerted by Hippopha? rhamnoides L. extract on the healing of experimental wounds in rats is studied histomorphologically in dynamics. The animals are divided up in three groups, as follows: group one--controls, group two--controls treated with indifferent carrier (carbopol gel), and group three--experimental, treated with carbopol gel containing extract of Hippopha? rhamnoides L. The wounds induced are standard, oval to elliptic with diameter about 3 cm. In groups I and II they are subjected to daily daubing over a 10-day period. The study of cytologic smears at 8, 24 and 48 hours, and biopsy performed on the 10th day show that in group three the epithelization is more intensive and occurs earlier, and granulation tissue differentiation (mature collagen fibers, profuse vascularity) is quicker, by comparison with groups one and two. The markedly expressed stimulating effect on the healing process is explained with the rich content of vitamins (A, C, E etc.) and microelements (sulfur, selenium, zinc, copper etc.) in the extract used.     

Calcification in an ageing Ligula intestinalis (L) plerocercoid from a bream (Abramis brama L.)

Light and transmission electron microscopy of the strobila of a large old Ligula intestinalis plerocercoid has revealed microcrystals with a morphology similar to that of microapatite crystals from vertebrates. Analysis of the microcrystals with EMMA-4 showed them to contain calcium and phosphorus. The tissue in the immediate vicinity of the microcrystals shows signs of necrosis while further away it is histologically normal.     

Termination of imaginal diapause of female Tetrix undulate (Sow.) (Orthoptera, Tetrigidae) by implantation of the corpora allata of an active female Locusta migratoria

The effect of implanted active corpora allata on the reproductive diapause in adult females of grasshopper, Tetrix undulata (Sow.) was investigated. Implantation of one corpus allatum originating from sexually mature, adult female Locusta migratoria donors effectively terminated reproductive diapause by inducing oocyte development and egg-laying. The diapause-break is the same in females reared at 8, 12, 16 hours light at 30 degrees or 25-20 degrees. There is no difference between females reared with male or without male.     

The importance of calmodulin in the accessory olfactory bulb in the formation of an olfactory memory in mice

Female mice form an olfactory memory to the pheromones of the mating male, during a critical period after mating. Failure to form this memory results in the male being treated as strange, and hence, his pheromones block pregnancy. Previous studies have shown that formation of this memory is dependent on synaptic mechanisms in the accessory olfactory bulb. A number of studies have pointed to calmodulin as a critical mediator of synaptic plasticity. In this study we have examined the effects of local infusions of drugs which block calmodulin-regulated processes, into the accessory olfactory bulb on the formation of this memory. Infusions of the calmodulin antagonist calmidazolium during the critical period prevented memory formation. However, the specific inhibitor of calcium/calmodulin-dependent protein kinase II, KN-62, or the selective inhibitor of calcium/calmodulin-dependent protein phosphatase 2B (calcineurin), FK506, was without effect on memory formation at any of the doses used. Instead of preventing memory formation, FK506 permitted the formation of a non-selective memory to strange male pheromones in the presence of mating, although FK506 alone could not induce a memory without the occurrence of mating. These results suggest that calmodulin in the accessory olfactory bulb is important in the formation of the olfactory memory to male pheromones. However, memory formation may be independent of calmodulin-kinase II. Calcineurin may play a role in processes antagonizing memory formation.     

The correlation of the ecological niches of the common (Rana temporaria L.) and of the moor (Rana arvalis Nilss.) frogs (Anura, Amphibia)]

During 25 years ecology and population dynamic of two brown frog species (Rana temporaria and R. arvalis) were studied in Moscow region, Solovki island and South Ural. We compared life cycles characteristics, namely biotope preferences, diet, migration, enemies, hibernation places using own and available literature data. Then we analyse how these parameters are changed among the species area and ecological niches were compared. We found that these two species do not compete in any stage of life cycle. Ecological niches are very closed and differences are determined generally by abiotic factors. So, R. temporaria prefers more wet biotope and more sensitive to acidity (low pH value). Differences in spawning time do not associate with interference in spawning places. We conclude that interspecific competition did not take place neither in the past nor in present and the reason of differences in ecological niches are determined by separate ways of evolutionary development of these species.     

Chemical constituents of Eclipta alba (L.) Hassk

Ecliptasaponin C (1), a new triterpenoid glucoside, was isolated together with daucosterol (2) and stigmasterol-3-O-glucoside (3) from Eclipta alba. Based on spectral analysis, chemical evidence and hydrolytic results, it's structure was deduced as 3-beta-O-beta-D-glucopyranosyl-19beta-hydroxy olean-12-ene-28-oic acid 28-O-beta-D-glucopyranoside, Compounds 2 and 3 were obtained from Eclipta for the fist time.     

Integument and sensillum auriforme of the opisthosoma of Rhipicephalus appendiculatus (Acari:Ixodidae)

The opisthosomal integument and sensilla auriformia of Rhipicephalus appendiculatus Neumann larvae, nymphs, females and males, both unfed, fed, and during molt, were examined by light and electron microscopy in relation to semiochemical production. The integument consists of epidermis, endocuticle, exocuticle, epicuticle, a superficial wax layer and a variable additional deposit. The integument of immature instars and females grows greatly during feeding. The integument is traversed by pore canals from the epidermis to the outer wax canals. The epidermis can secrete material to the exterior by way of the pore canals and wax canals. The sensillum auriforme is a common disk-shaped organ, with a complex internal chamber open to the exterior by way of a pore. It has no apparent secretory capacity and is of presumed sensory function. It is located in the integument of scutum and alloscutum of all instars.     

Chemical constituents of Luffa cylindrica (L.) Roem

Six compounds were isolated from the fruits of Luffa cylindrica. They were identified as lucyosides C, E, F, H, a mixture of alpha-spinasterol and stigmasta-7,22,25-trien-3 beta-OH and a mixture of alpha-spinasteryl glucoside and delta 7,22,25-stigmasteryl-beta-D-glucoside by means of chemical evidence and spectral analysis.     

壳聚糖对长豆角品质和产量的影响

[目的]为生产长豆角无公害寻找有效的生长调节剂.[方法]在长豆角现蕾前,采用1.2和1.6 mg/ml壳聚糖溶液喷洒长豆角植株,研究其豆荚品质和产量的变化.[结果]壳聚糖有效减少了长豆角虫害的发生,提高了长豆角豆荚可溶性蛋白含量、可溶性糖含量和维生素C含量,降低粗纤维含量,并增加了单果重量、单株结荚数和单位面积产量.[结论]壳聚糖作为一种植物生长调节荆,显著增加作物产量和改善作物营养品质.     

Effect of bioresmethrin on mitochondrial ultrastructure and oxidative phosphorylation in the flight muscles of Chrysomya albiceps (Wied.) (Diptera: Calliphoridae)

The sublethal effect of bioresmethrin on the ultrastructure, oxidation and phosphorylation of flight muscle mitochondria in the blow fly Chrysomya albiceps which survived treatment of newly formed pupae (0-day old) with 10 micrograms/pupa (LD30) was studied. The ultrastructure of the flight muscle mitochondria was severely deteriorated by treatment with bioresmethrin. The deterioration included disalignment and sometimes destruction of the cristae and vacuolation of mitochondria. The oxidation rate was decreased in treated flies, although the P/O ratio was increased. The present study may indicate that bioresmethrin is neither an uncoupler nor a direct inhibitor of oxidative phosphorylation but may have functioned as an inhibitor of the oxidation rate.     

Ontogeny of the endocrine cells of the intestine and rectum of sea bass (Dicentrarchus labrax L.): an ultrastructural study

Several endocrine cell types were ultrastructurally characterized during the differentiation of the intestine and rectum of sea bass (Dicentrarchus labrax L.) larvae. Only one cell type (type I) was found in the posterior region of the undifferentiated gut of 5-day-old larvae (phase I). Types V and VI were found in both the intestine and rectum, types II, III and IV in the intestine, and types VII and VIII in the rectum of 9- and 12-day-old larvae (phase II), the rectum alone showing signs of functional differentiation. In phase III larvae, in which both the intestine and rectum were differentiated, types IX, X, XI, XII, XIII, XIV and XV were found in the intestine, only types X, XI and XII being seen in the rectum. Besides these, a new cell type, XVI, was observed in the intestine of 55- and 60-day-old larvae (phase IV), in which the digestive tract was completely differentiated. The endocrine cells appearing in phases I and II showed very scarce secretory granules and the ultrastructural features of undifferentiated cells. Some endocrine cell types in the earliest developmental stages were related to some of those found later. A maturational process of the endocrine cell types paralleled the differentiation of the intestine and rectum, with an apparent increase in the number of secretory granules accompanying organelle development.     

酸藤子化学成分的初步研究

[目的]初步研究酸藤子中可能含有的化学成分.[方法]采用常规化学反应鉴别方法检测酸藤子的化学成分.[结果]糖、多糖、苷类、鞣质、有机酸、黄酮、酚类、挥发油等检测项目出现正反应;其余项出现负反应现象.[结论]该研究为进一步进行该植物的生物活性成分研究提供了试验基础.