棉铃虫血细胞对葡聚糖凝胶珠的包囊反应

研究了棉铃虫Helicoverpa armigera(Hübner)血细胞对葡聚糖凝胶珠的包囊反应。结果表明:棉铃虫血细胞对不同类型的葡聚糖凝胶珠具有不同的包囊能力,其中对SephadexA-25葡聚糖凝胶珠具有很强的包囊能力;棉铃虫血细胞启动对SephadexA-25葡聚糖凝胶珠的包囊反应是较迅速的,而包囊的完成大概是在凝胶珠进入棉铃虫体内12h之后;在离体的情况下,棉铃虫血细胞仍然能包囊葡聚糖凝胶珠。     

草履蚧血细胞的显微形态与超微结构观察

为研究蚧虫血淋巴中血细胞的种类及其结构特征,采用相差显微镜、荧光显微镜和扫描电镜与透射电镜技术,观察了草履蚧雌成虫血细胞的显微形态与超微结构特征.结果显示,在荧光显微镜和扫描电镜下观察识别出草履蚧血淋巴中的5种血细胞,即：原血胞、浆血胞、粒血胞、囊血胞和类绛色血细胞.在透射电镜下可见,原血胞的细胞核明显,表现出高的细胞质密度;浆血胞最典型的特征是细胞质中有大量的囊泡;粒血胞的细胞质中有发达的粗面内质网和许多玫瑰形的细颗粒.类绛色血细胞最典型的特征是有许多结晶,并在细胞质的空泡区内分布的更多.囊血胞透明性强,具有围核空间,膨大成潴泡状.     

白蜡绵粉蚧血细胞的显微形态与超微结构观察

为研究蚧虫血淋巴中血细胞的种类及其结构特征,本文采用荧光显微镜、扫描电镜和透射电镜观察了白蜡绵粉蚧Phenacoccus fraxinus Tang(半翅目:蚧总科:粉蚧科)雌成虫血细胞的显微形态超微结构.结果显示,在荧光显微镜和扫描电镜下观察识别出白蜡绵粉蚧血淋巴中的5种血细胞,即原血胞、浆血胞、粒血胞、类绛色血胞和囊血胞.在透射电镜下,原血胞的细胞核明显,表现出高的细胞质密度;浆血胞最典型的特征是细胞质中有大量的囊泡;粒血胞的细胞质中有发达的粗面内质网和许多玫瑰形的细颗粒;类绛色血胞最典型的特征是有许多结晶,并在细胞质空泡区内分布更多;囊血胞透明性强,具有围核空间,膨大成潴泡状.     

Drift and upstream movement of invertebrates in a springbrook community ecosystem

Structure, drift, and upstream movement of populations of benthic macroinvertebrates, in particular Synurella dentata Hubricht and Lirceus fontinalis Raf., were examined within a temperate spring ecosystem. Chemical and physical aspects of the springbrook were also investigated and life histories of the gammarids and asellids noted.Chemically and physically the spring proved both constant and predictable, much more so than other lotic systems.Species diversity was low from November through February and increased in March, April, and May. Equitability followed the same trends as species diversity. Both indices were most affected by large fluctuations in the populations of aquatic insects.Significant changes in the numbers of amphipods, isopods, and total macroinvertebrates was evident over a seven month period. Males were present in the isopod population year-round, but only from November to January in the amphipod population. Breeding by the isopods occurred throughout the year and peaked during winter. Amphipods copulated only in the late fall and early winter.Significant diel peaks in the amphipod, isopod, and total invertebrate drift negatively correlated with light intensity levels. Amphipods and isopods did not exhibit any preferential upstream movement during either the day or night; however, total macroinvertebrate upstream movement was greater at night. The total number of invertebrates moving upstream were lower than values reported from other lotic environments.     

Effects of hemolymph of the American oyster, Crassostrea virginica, on marine cercariae

The interactions of cellular and humoral factors of hemolymph of the American oyster, Crassostrea virginica, and several species of marine cercariae were studied. Attraction of hemocytes to dead but not to living cercariae was observed. Dead cercariae were encapsulated in vitro by oyster hemocytes. The plasma of C. virginica was apparently not toxic to the species of cercariae tested.     

Hemolymph melanization and alterations in hemocyte numbers in Lymantria dispar larvae following infections with different entomopathogenic microsporidia

Lymantria dispar (L.) (Lepidoptera: Lymantriidae) larvae can be infected in the laboratory with a variety of entomopathogenic microsporidia. In many cases, however, L. dispar is only a semi‐permissive host for such infections. In this study, we analyzed changes in the melanization of hemolymph and hemocyte numbers in L. dispar larvae after inoculation with various entomopathogenic microsporidia. We compared the infections produced by microsporidia isolated from L. dispar and infections produced by isolates from other Lepidoptera to which L. dispar is only a semi‐permissive host. Microsporidiosis induced a significant activation of the prophenoloxidase system leading to melanization; activation was highest when the pathogen caused heavy infections of the fat body, which was the case with two microsporidia originally isolated from L. dispar. Infection of only the silk glands or light infection of the fat body by two Vairimorpha spp. from other lepidopteran hosts elicited a lower response. Very light infections caused by a microsporidium isolated from Malacosoma americanum were not accompanied by elevated hemolymph melanization activity. Heavy infections by Endoreticulatus spec. that remained restricted to the gut tissue likewise did not elicit melanization. One Vairimorpha spec. from L. dispar induced a significant increase in total hemocyte numbers; the other infections led to temporarily decreased numbers. Microscopic examinations showed that parts of infected tissue were encapsulated by hemocytes. We conclude that measured alterations in hemolymph melanization and hemocyte numbers were likely to be induced by the damaging effects of heavy infections. Observed defense responses did not prevent the progression of infections.     

Sex-reversal and androgenic gland in the fish parasite Irona far (cymothoidae: isopoda: crustacea)

The sequence of changes in the primary and secondary sexual characters of the parasitic isopod Irona far during sex-reversal indicate that it is synchronised with the degeneration of the androgenic gland. The gonad is typically hermaphroditic. During the male stage the testicular utricles are large and active but the ovarian region remains undifferentiated. During the intermediate stage production of sperms is stopped and the ovarian region produces ova but without vitellogenesis in them. In the female stage the testicular utricles regress, ovary enlarges and there is increase in egg production and vitellogenesis. The male secondary sexual characters become highly developed during the male stage, regress in the intermediate stage, and finally disappear in the late female stage. Only during the female stage does the female secondary sexual character, viz, the oostegites appear. The androgenic gland shows signs of maximum secretion during the prepuberal and puberal male stages and least activity during the intermediate and early female stages, leading ultimately to total degeneration in the late female stage.     

Ultrastructure and distribution of identified neurosecretory terminals in the sinus gland of the terrestrial isopod Oniscus asellus

An ultrastructural study of the sinus gland of the terrestrial isopod, Oniscus asellus, reveals that this structure consists of two regions: the bulb, which is attached by a narrow stalk to the optic lobe, and the lateral extension, which extends from the bulb along the optic tract to the compound eye. The bulb has a distal region containing only neurosecretory terminals, and a proximal region containing terminals, glial cells, and axons that give rise to the distally located terminals. In total, the sinus gland contains five types of terminals which can be distinguished by their location and the appearance of their neurosecretory granules. Three terminal types are located in the bulb and two in the lateral extension. The size of the terminals in the bulb varies among the three types, but the number of terminals is approximately the same for each type. Conversely, the two terminal types in the lateral extension are similar in size, but differ in number. Axons of two terminal types in the bulb can be traced to the central region of the protocerebrum; axons of one terminal type in the bulb and of terminals in the lateral extension can be traced to the optic lobe.     

Lobster (Homarus americanus) hemocytes: Classification,differential counts,and associated agglutinin activity

Four hemocyte types were recognized in the lobster based on size and refractile nature of the granules, the ratios of cytoplasm to nucleus, and Giemsa stain characteristics. Two hyaline types were designated as prohyalocytes (1.8%) and hyalocytes (64.2%), and two granular types were termed eosinophilic granulocytes (12.2%) and chromophobic granulocytes (21.9%). There was no significant difference in the percentages of the different hemocyte types (differential hemocyte counts) between sexes, but hyalocyte and eosinophilic granulocyte percentages varied significantly between populations of lobsters. The data suggested that the difference in agglutinin activity (HA) between lobsters with the same total hemocyte numbers was due to activity associated with fixed hemocytes or quantitative differences in HA activity associated with one or more hemocyte types, rather than an increase in the percentage of any one particular type in circulation.