The early development of the tail and the transformation of the shape of the nucleus of the spermatid of the domestic fowl,Gallus gallus

Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices     

Characterization of the composition of the aqueous humor and the vitreous body of the eye of the frog Rana temporaria L

This study aimed to analyze the aqueous humor (AH) and the vitreous body (VB) of the eye of the adult frog Rana temporaria L. as a representative species of amphibians, which lead a semi-terrestrial life. The presence of collagen, albumin, uric acid and electron donors was shown in both media; however, there are slight differences in their concentrations. To determine collagen, a spectral-fluorescent probe, cyanine dye, was used. The presence of collagen in AH of the frog was found at the first time. The total content of electron donors (ascorbic and uric acids, tryptophan, and tyrosine) in VB and HA was roughly estimated at ~ 1.5 × 10^− 4 mol/L. Both VB and AH absorb light in similar UV regions. The total protein and albumin contents in AH were found to be somewhat higher than those in VB. The uric acid content was at an equally low level in both intraocular media. It is supposed that the similarity of VB and AH compositions shown in this work is due to some exchange between VB and AH contents in the course of accommodation. The role of intraocular fluids in physiological functions of the eye and in protecting the retina against UV light is discussed.     

Light microscopic features of the rete testis,the vas efferens,the epididymis and the vas deferens in the adult rhesus monkey

The present study was carried out to determine the detailed histological and cytological features of the excurrent ducts of the male reproductive system in the rhesus monkey. The excurrent ducts show a regional difference in their histological features. The use of some of these features as histological markers and their possible functional significance are discussed. The epithelial cells in the different components of the excurrent duct system possess cytological features which suggest their involvement in absorption and the secretion of different products into the lumen.     

Dissymmetry of the origins of the roots of the spinal cord in the dog

The spinal cord in 25 non-inbred dogs has been studied macro-microscopically. The dissymmetry in the arrangement level in the right and left root bases on the dorsal surface of the spinal cord is much greater than on the ventral surface. The same as in the human being, the dissymmetry is the greatest in the thoracic part (as compared to other spinal parts). On the ventral surface of the spinal cord both along the anterior and posterior margin of the root bases, there is a right-sided dissymmetry (with cranial shift); on the dorsal surface it is present only at the roots along the posterior margin. The dissymmetry of the dog spinal cord is quantitatively estimated along its whole extension.     

Transport of material between the nucleus,the chromatoid body and the golgi complex in the early spermatids of the rat

Summary The movement and transport of material between intranuclear dense particles, the chromatoid body and the Golgi complex have been studied in early spermatids of the rat. The analyses involved observation of living accurately identified cells, time-lapse cinemicrography and electron microscopy.The chromatoid body establishes transient contacts with intranuclear material during early spermiogenesis. The chromatoid body also makes contacts with the Golgi complex. It is suggested that the chromatoid body receives material from the nucleus during the postmeiotic period and participates in the early formation of the acrosomic system.This work was supported by the Finnish National Research Council for Medical Sciences. The authors are grateful to Mrs. Marita Aaltonen and Mrs. Raija Andersen for their skilful technical assistance     

About the morphological relationships of the sarcoplasmic reticulum in the sole plate area of the frog

In the present investigation the sole plate area of motor end plates of the frog is ultrastructurally examined with different postfixation methods. We concentrated in this case on the proof of the smooth and rough sarcoplasmic reticulum of the sole plate. The relations of the smooth and rough sarcoplasmic reticulum to subsynaptic folds and the local T-system and its connections to diads and triads in the sole plate area are represented. The morphological differences between mammal and frog are pointed out. The possible functions of the sarcoplasmic reticulum in the myofibril-free sarcoplasm are discussed.     

Palynostratigraphy of the Carboniferous at the margin of the Polish part of the East-European platform

The paper presents results of miospore studies on Carboniferous strata from drillings made in the last 20 years in several regions in marginal zones of the East-European Platform in Poland (Lublin Coal Basin, Warsaw, Płock, and Bydgoszcz regions, and western Pomerania). In that area the Carboniferous is represented by Dinantian and Silesian strata, from the Tournaisian to Westphalian D.Because of differences in geological development of the Carboniferous and in composition of microfloristic assemblages from strata of that age in the above mentioned regions the first stage of the studies had to be aimed at compilation of local palynostratigraphic schemes for individual regions. The next stage involved compilation of a regional palynostratigraphic scheme for the whole area of Polish margin of the East-European Platform. The scheme comprises 16 spore zones of the concurrent-range-zone type: 6 for the Dinantian and 10 for Silesian. The detailed characteristics of miospore assemblages and age correlations of the zones are given.The proposed scheme was subsequently compared with that proposed for the Carboniferous in western Europe. The comparison showed marked similarities in ranges of taxa diagnostic for individual stratigraphic units in both schemes.     

Observations on the permeability of the choriocapillaris of the eye

Summary The choriocapillaris is a fenestrated capillary bed located posterior to the retinal pigment epithelium. It serves as the main source of supply to the photoreceptors, retinal pigment epithelium, and other cells of the outer retina. The permeability of these capillaries to intravenously injected ferritin (MW — approx. 480,000; mol. diam. 11 nm) was examined in the mouse, rabbit, and guinea pig, each of which is characterized by a different type of retinal vascularization. In all three species, the bulk of the ferritin remained in the capillary lumina, where it appeared to be blocked at the level of the diaphragmed fenestrae. Some ferritin was present in endothelial cell vacuoles. The results confirm previous work on the rat choriocapillaris and indicate that the barrier function of the choriocapillary endothelium is present even among species in which the retinal circulation differs significantly.Supported by NIH grant EY03418     

Effect of the chemical nature of the carbon source in the medium on the makeup of the biomass]

The yeast Candida tropicalis, Candida utilis, Trichosporon cutaneum were cultivated on the synthetic medium containing additions of group B vitamins (biotin, thiamin) and glucose, glycerol of lactic acid as the sole source. The protein content, amino acid composition, nucleic acids and complex B vitamins were identified in the resultant biomass. The carbon source in the medium affected these indices. The protein and nucleic acid content also depended on the yeast strain.     

Characteristics of the membranes of the pellicle of the ciliatePseudomicrothorax dubius

Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles.     

Histogenesis of the taste buds of the vallate papilla in the in the rat in the postnatal stages of development

The developing taste buds of vallate papillae were studied with electron microscope in rats during the first 7 days after birth. Two types of cells--light and dark--are identified in the taste buds of a one day old animal. The apical parts of dark cells are characterized by numerous dark granules. A distinguishing feature of light cells is the presence of synaptic contacts with afferent intragemmal nerves. On the 4th day of development on the top of the apical parts of the cell, a microvillar apparatus is seen to form, which does not yet communicate with the oral cavity. On the 7th day, basal cells appear in the taste buds. Some of these cells are seen mitotically dividing. The differentiated microvillar apparatus now communicates with oral cavity. The structure of the taste buds is getting similar to that in the adults. The structural and functional peculiarities of the developing taste buds are discussed in association with the period of ontogenesis under consideration.     

Observations on the projection from the perihypoglossal nuclei onto the cerebellum in the macaque monkey

The occurrence and distribution of retrogradely labeled cells in the perihypoglossal nuclei of the monkey were mapped after injections of horseradish peroxidase in various cerebellar cortical regions. In general the findings are in accord with those made in the cat. The flocculus receives a heavy bilateral projection from the nucleus prepositus, particularly from its caudoventral part, and from the nucleus of Roller. There is an apparently scanty projection from the nucleus intercalatus. The uvula receives a rather similar projection, but in the prepositus the cells projecting to the uvula are on the whole situated more dorsally and rostrally than those supplying the flocculus. The projection to lobules VII-VIII is distinct. More scanty projections have been found to the paramedian lobule and the anterior lobe. The different but partially overlapping sites of origin in the prepositus of fibers to the flocculus and uvula indicate the presence of a topical pattern within the perihypoglosso-cerebellar projection, as in the cat (34). In the monkey the two regions of origin appear to coincide with two particular cell collections in the prepositus (12). Both small and middle sized cells project to the cerebellum, as they do in the cat (9, 48). The nucleus supragenualis nervi facialis in the macaque is morphologically different from the corresponding nucleus in most other mammalian species (12), but it contains labeled cells after injections in the flocculus, uvula and other cerebellar regions. A considerable number of cells in the abducent nucleus are labeled after injections in the flocculus and the posterior vermis.     

Ultrastructure of the surface of the iris in the rat eye

Summary The surface structure of the iris in the rat eye was studied by light and electron microscopy.The anterior surface of the rat iris is covered with a discontinuous layer of large, polygonal endothelial cells with microvilli on their surface. Crypts and holes between adjacent endothelial cells extend into the stroma and form there a complicated network of interconnected spaces occupying about one half or more of the volume of the pupillary part of the stroma. The crypts are occasionally partly covered with endothelial cells. The posterior surface is covered with a continuous layer of polyhedronal epithelial cells. These are covered with many folds and processes, partly masked by an amorphous coat. The sphincter pupillae and dilatator muscles are possible to recognize on the scanning electron micrographs as well as blood vessels and nerve fibers in the iris stroma.The endothelial cells show many structural similarities with the endothelial cells on the cornea, probably reflecting their common origin. The results obtained, especially those from the scanning electron microscopic studies, are discussed and interpreted in relation to previous studies. The advantages in using different light and electron microscopic techniques are stressed.Supported by grants from Magnus Bergwall's Stiftelse and the Swedish Medical Research Council (B71-12X-2543-03).     

迷迭香对运动大鼠肝脏组织脂质过氧化损伤保护作用的研究

本实验选用SD(Sprague Dawley)大鼠,建立大强度耐力训练模型,研究迷迭香对运动大鼠肝脏组织脂质过氧化损伤保护作用。结果显示,1)迷迭香可降低血清丙氨酸氨基转移酶活性,升高肝组织丙氨酸氨基转移酶的活性,都有显著性差异(P<0.05);2)迷迭香可以不同程度地增强肝脏组织中抗氧化酶SOD(superoxide dis-mutase)、CAT(catalase)和GSH-Px(glutathione peroxidase)的活性,其中SOD和CAT的活性增加在安静和运动状态下都有显著性差异(P<0.05),GSH-Px的活性增加在运动状态下具有显著性差异(P<0.05);3)迷迭香可以降低肝脏组织中MDA(malondialdehyde)的含量,无显著性差异(P>0.05)。结论:迷迭香可以增加肝脏组织中的抗氧化酶活性,减轻大强度耐力训练对大鼠肝脏组织造成的脂质过氧化损伤。并且在同一状态下对不同的抗氧化酶活性影响不同。     

Characteristics of the ovum cleavage and the importance of the preblastula phase in the embryogenesis of the Nematoda

The figure of tetrahedron is formed in certain species of Plectus and in Tobrilus gracilis at the stage of 4 blastomeres rather than a rhombus which is formed in most highly organized nematodes. The analysis of the Nematoda's embryogenesis allows to conclude that tetrahedron, rhombus as well as some other figures play the role of preblastula sustaining the most expedient disposition of the first blastomers for transition to the formation of the blastula. With the increasing organization of nematodas the tetrahedron preblastula turns into a rhombic, linear-rhombic and at last in aphelenchoid-tylenchoid one. The character of the distribution of structural elements of organs and tissues of the definitive animal in the cytoplasm of the egg of Plectus and Tobrilus confirms the rightness of the division of the class of nematodas into subclasses Enoplia and Chromadoria rather than subclasses Adenophorea and Secernentea.     

Ultrastructural changes in the oviduct of the laying hen during the laying cycle

The ultrastructural changes occurring in the fully functional oviduct of Isa Brown laying hens were studied during various stages of the laying cycle. Hens were killed at different positions of the egg in the oviduct. The oviduct was lined by ciliated and non-ciliated cells (also referred to as granular cells). The granular cells in the infundibulum contributed to secretion during egg formation, whereas ciliated cells showed little evidence of secretion. Ultrastructural changes were recorded in the granular and glandular cells of the distal infundibulum. In the magnum, the surface ultrastructure revealed glandular openings associated with the ciliated and granular cells. Cyclic changes were recorded in the glandular cells of the magnum. With respect to the three observed types of glands, the structure of gland type A and C cells varied at different egg positions in the oviduct, whereas type B cells represented a different type of gland cell containing amorphous secretory granules. The surface epithelium of the isthmus was also lined by mitochondrial cells. Two types of glandular cell (types 1 and 2) were recorded in the isthmus during the laying cycle. Intracisternal granules were found in type 2 cells of the isthmus. A predominance of glycogen particles occurred in the tubular shell gland. The granular cells in the shell gland contain many vacuoles. During egg formation, these vacuoles regressed following the formation of extensive rough endoplasmic reticulum; the reverse also occurred. The disintegrated material found in the vacuoles may have been derived from the disintegrating granules. The Physiology Teaching Unit, University of New England, provided financial support to K. Chousalkar for this study.     

Analysis of the mechanisms determining the varying relationship of the sperm from the marine and freshwater forms of the three-spined stickleback to the salinity of the medium]

The causes of differences in the reaction of spermatozoa of the fresh-water (morpha leiurus) and marine (m. trachurus) forms of three-spined stickleback Gasterosteus aculeatus to the high sea water salinity (the upper limit of spermatozoan motility being 18% and 52%, resp.) were investigated. The experiments with solutions of pure NaCl, CaCl2, MgCl2, KCl, LiCl (25 g/l) have shown that the movement of spermatozoa of m. leiurus is inhibited by NaCl only. The inhibition of chlorine channels of the plasma membrane by a specific inhibitor furosemide has shown that the activity of spermatozoa of m. leiurus is suppressed by the high Na+ concentrations. The experiments with ATP have revealed no differences in the activity of Na pump between the spermatozoa of mm. trachurus and leiurus. Amyloride, an inhibitor of Na channels, at a concentration of 1.10(-5) M relieved the inhibiting effect of the high Na+ concentrations on the activity of spermatozoa of m. leiurus. The differences in the reaction of spermatozoa of two forms of the stickleback appear, to be determined by differences in Na channels of the plasma membrane.     

On the homology between the X and the Y chromosomes of the Chinese hamster

The chiasmatic association of the heteromorphic sex chromosomes in the spermatocytes of the Chinese hamster was observed in squash and/or air-dried preparations. The pairing arm of the Y was invariably its short arm. Although the X in diakinesis did not show distinct long and short arm as in mitotic metaphase, the DNA replication patterns of the sex chromosomes in spermatogonia suggested that the distal segment of the long arm of the X is homologous to the short arm of the Y.     

Progress in the study of the lichen flora of the British Isles

SEAWARD, M. R. D., 1987. Progress in the study of the lichen flora of the British Isles. Advances in our taxonomic, ecological and geographical knowledge of the lichen flora of the British Isles over the past three centuries are assessed. The growth of literature and the development of field recording are critically surveyed, complemented by numerical and cartographical analyses. The evolution of a comprehensive programme of network recording is described and evaluated. The present and future use of technological advances, particularly in respect of computer databases, is examined.