Localization of Glyoxylate Cycle Enzymes in Glyoxysomes in Euglena*

SYNOPSIS. We demonstrated previously microbodies in Euglena gracilis grown in the dark on 2-carbon substrates. We have now established in Euglena the particulate nature of enzymes known in other organisms to be localized in microbodies (glyoxysomes and leaf peroxisomes). On a linear sucrose gradient the glyoxylate cycle enzymes band together at a nigner equilibrium density (1.20 g/cm3) than mitochondrial marker enzymes (1.17 g/cm3), establishing the existence in Euglena of glyoxysomes similar to those of higher plants. Glyoxylate (hydroxypyruvate) reductase and, under certain conditions, also glycolate dehydrogenase co-band with the glyoxylate cycle enzymes, suggesting that Euglena glyoxysomes, like those of higher plants, may contain peroxisomal-type enzymes. Catalase, an enzyme characteristic of microbodies from a variety of sources, was not detected in Euglena.     

Observations on the Endogenous Stages of Eimeria confusa Joseph, 1969 from the Grey Squirrel Sciurus carolinensis*

SYNOPSIS. Stages in the endogenous cycle of Eimeria confusa from the grey squirrel, Sciurus carolinensis, are described from mixed infections with another species, Eimeria lancasterensis. All corresponding stages were markedly different in the 2 species. In E. confusa infections, the parasites were located below the host cell nuclei of the epithelial cells of the villi of the jejunum and ileum. Mature schizonts were ellipsoidal, averaged 20.9 × 18.6 μm and had 18–30 merozoites. The mature microgamonts measured 34.3 × 24.7 μm and had hundreds of microgametes. Mature macrogametes were ovoid, averaged 31.3 × 25.6 μm, and contained 2 kinds of plastic granules.     

Organic Acids of Ditylenchus triformis and Turbatrix aceti

Pyruvic acid, lactic acid and several tricarboxylic acid cycle acids were extracted from Ditylenchus triformis and Turbatrix aceti and identified. Fumaric acid was predominant in both nematodes. Small amounts o f malic and α-ketoglutaric acids and intermediate quantities o f lactic, citric, succinic, and pyruvic acids occurred in D. triformis. In T. aceti citric, lactic, and α-ketoglutaric acids were less abundant than succinic, malic and pyruvic acids. Only traces of aconitic and oxalacetic acids occurred in both nematodes. All the organic acids detected accounted for only about one per cent of the dry weight of nematodes o f the two species.     

Biochemical and physiological studies of certain ticks (Ixodoidea): specific gravity of hemolymph and coxal and gut fluids of Argas (Persicargas) persicus and Argas (Persicargas) arboreus (Argasidae)

Specific gravity (sp. gr.) of cell-free hemolymph and gut and coxal fluids was determined at different states of the gonotrophic cycle (unfed + 15 days, engorgement day before and after coxal fluid emission, engorgement + 1 day, oviposition day, and oviposition completion + 1 day) of female Argas (Persicargas) persicus and A. (P.) aboreus (Argasidae). The patterns of hemolymph and gut fluid sp. gr. change differed from each other during the gonotrophic cycle, but both patterns were similar in the 2 Argas species. Hemolymph sp. gr. decreased to a minimum one day after feeding (1.0085 and 1.0081 for persicus and arboreus, respectively), and increased through oviposition to a maximum on oviposition + 1 day (1.0187 and 1.0221). Minimum gut fluid sp. gr. occurred on engorgement day before coxal fluid emission (1.0565 and 1.0697). Afterward, gut fluid sp. gr. increased to a maximum on engorgement day + 1 for persicus (1.1089) and on oviposition day for arboreus (1.0973), and then decreased during oviposition in both species. In each tested state of each species, the sp. gr. was consistently higher in gut fluid than in hemolymph. In each species, coxal fluid and hemolymph sp. gr. were the same on engorgement day.     

Evolution cyclique des glandes cérébrales au cours de l'intermue chez Lithobius forficatus L. (Myriapode Chilopode)

Résumé Chez le Chilopode Lithobius forficatus L., les cellules parenchymateuses des glandes cérébrales présentent, durant l'intermue, un cycle sécrétoire caractérisé essentiellement par l'évolution de l'activité golgienne. Pendant les périodes de sécrétion, les ribosomes, groupés en polysomes, et les éléments ergastoplasmiques sont très abondants; pendant les périodes de repos, les ribosomes sont isolés et l'ergastoplasme est vésiculeux. Les autres organites cellulaires montrent peu de variations.Le cycle sécrétoire ne se superpose pas exactement au cycle d'intermue; il commence lors de la prémue. Peu de temps après l'exuviation, il est possible d'observer des figures qui semblent liées au rejet du produit de sécrétion. L'étude ultrastructurale des glandes cérébrales en fonction de l'intermue confirme l'existence de l'activité cyclique mise en évidence par les résultats expérimentaux.

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Ultrastructural signs of cyclic secretory activity in the cerebral glands of Lithobius forficatus during intermolt

Summary During the molting cycle of Lithobius forficatus L. (Chilopoda), the parenchymal cells of the cerebral glands exhibit signs of cyclic secretory activity consisting essentially of changes in the appearance of the Golgi complex. During active periods of secretion, polysomes and ergastoplasmic elements are very numerous; free ribosomes and vesiculated ergastoplasmic cisternae characterize the periods of inactivity. Other cytoplasmic organelles undergo few variations. The secretory cycle as determined by cytological criteria does not exactly match the molting cycle. The first ultrastructural signs of activity appear during premolt. Shortly after ecdysis, images suggesting the release of secretory material can be observed. The electron microscopic data on cyclic changes during intermolt substantiate the existence of activity cycles in the cerebral glands as determined by physiological experiments.

     

Cyclical changes in the fine structure of bovine endometrial gland cells

Summary Cyclical changes in bovine endometrial gland cells were investigated in six heifers, three at estrus and three at day twelve of the estrous cycle in the luteal phase. The epithelium is generally low at estrus but high in the luteal phase. There are ciliated and non-ciliated cells. The ciliated cells are fewer and lighter and show inconspicuous cyclical changes.The secretory cells show more prominent changes. At estrus, their free border is flat with short microvilli. The conspicuous rough-surfaced endoplasmic reticulum may synthesize protein for later secretion. The Golgi complex seems inactive. The high number of cytosegresomes and dense bodies might express cell regression caused by endocrine changes.In the luteal phase, the cells are lighter with long microvilli. The Golgi apparatus shows vacuoles and immature secretory droplets. Secretory vacuoles with light contents occur in the apical cytoplasm. Some of them appear to discharge their contents into the lumen. This is interpreted as evidence of merocrine secretion. Accumulations of tubular, smooth-surfaced endoplasmic reticulum, masses of glycogen granules, and several fat droplets are present.Some lymphocytes and degranulated granulocytes are seen near the basement membrane, more frequently at estrus.Financial support for this study was received from Anslaget för främjande av medicinsk forskning vid Veterinärhögskolan.The authors express their gratitude to Prof. A. Bane and Dr. J.-E. E. Ringmar, Department of Obstetrics and Gynecology, for their help with the selection and clinical control of the animals and for keeping them in good condition.Post doctoral fellow, No. 43-KO-52 (1968) from the Educational Ministry of Japan.     

Some Eugregarines (Sporozoa, Apicomplexa) from the Stored Fruit Beetle, Oryzaephilus mercator Fauv. (Coleoptera) from India

Morphology and life history of 3 cephaline gregarines found in the gut of the pest of stored fruit, Oryzaephilus mercator. are described. Of these 3, 2 are new species. The 3 species are (1) Hirmocystis minuta (Ishii, 1914) (LP TL = 1:7 – 1:22, WP/WD = 1:1, 6–1:7); (2) Amsotobus indicus n. sp. (LP/TL = 1:3–1:6, WP/WD = 1:1 – 1:1.3); (3) Leidyana oryzaephili n. sp. (LP/TL = 1:2 – 1:12; WP/WD = 1:1–1:1.6).     

A method for studying vegetation dynamics when there are no obvious individuals: Virtual-population analysis applied to the tundra shrub Betula nana L.

A method is presented to study dynamics of plants that cannot be separated into individuals such as many grassland, salt marsh and tundra species. A virtual population is created by using a permanent transect line through the vegetation and individuals are defined as the branch segments distal to the intercept with the transect line. Addition and loss of individuals together with growth or shrinkage form the basis for constructing a size-structured transition matrix. A discrete-event simulation demonstrates that: 1) a virtual population of individuals grows at the same rate as the parent population; and, 2) size-structured transition matrices for a virtual population and parent vegetation have similar dominant and subdominant eigenvalues so a virtual population can be used to describe the dynamics of a parent vegetation.Dwarf birch, Betula nana L., was studied in the northern foothills of the Brooks Range, Alaska, by using photography to record branch intercepts along permanent transect lines. The distal branch segments constitute a virtual population of the parent vegetation. Transects were photographed in 1985 and again in 1986 and changes of branch segments were used to construct two transition matrices for shrubs with and without elevated fertilizer treatment. Analysis of the virtual populations suggests that although Betula nana may show increased branch growth with increased fertilizer, in the long run this shrub may decline in the tundra in response to such treatment.     

人胃癌不同周期细胞膜表面ConA受体的分布与侧向运动

本文研究了人胃低分化粘液性腺癌细胞MGC 80-3不同周期时相中ConA受体的分布与侧向运动。MGc 80-3细胞经同步化培养,用F-ConA标记。被标记细胞中G_1、S和G_2期呈不连续的分布,但它们之间又存在显著的差异。M期呈较均匀的强荧光分布(与其它时相细胞比较)。荧光漂白恢复方法测定ConA受体复合物侧向运动表明:各个周期时相之间不仅运动方式不同,而且运动速率也有显著差异。M期与G_1期主要表现出扩散型运动;而S期与G_2期表现为流动型运动。G_1期的扩散系数大干M期的;S期的流动速率大于G_2期的。但可动分子百分比以G_2期最高。这些结果表明了ConA受体的动力学性质。它受到细胞周期的调节。     

The reproductive biology of female Père David's deer (Elaphurus davidianus)

Data for this study came from breeding records of 27 Père David's (Elaphurus davidianus) hinds maintained in large pastures and from estrous records of four hand-reared nulliparous hinds. The mean estrous cycle length ranged from 17.5 to 19.6 days. Standing estrus resembled that of other cervids, except that a low, moaning vocalization was given in response to contact, and activity (as measured by pedometers) did not increase. Mean gestation length was 183.38 ± SD 6.11 days (n = 21), and nearly all females conceived in the second and third years. The median interbirth interval was 362 days. The median birth date was April 8, and 80% of the births occurred over a 9.5-week period. Multiparous hinds gave birth an average of 20.5 days earlier in the season than primiparous hinds. There was no dimorphism in birth weight. The results are discussed in light of comparative data for other species.