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Structure and composition of severely defective eggshells of larus ridibundus
164
SCANDEM-90
The seeds seem to be adapted to wind dispersal and rapid water uptake: the outer epidermal walls are invaginated into the epidermal cells in dry seeds, but bulge in moistened seeds. The remaining part of the seed coat consists of two different single ‘palisade layers’ and a multilayer of compressed parenchyma cells. The endosperm has an outer aleuron layer followed by starch filled cells. The outer cells walls are covered by a cuticle. The other walls are gelatinous and absorb water readily. A dry seed is very light. The embryo cells are stored with lipids and protein. An indication of small cell bridges interconnecting the coils of the embryo is an interesting feature. The newly germinated seedling has a tuberous radicular end lacking a root meristem and a fihiform axis lacking cotyledons, but with a greenish apex. The tuberous end consists of large highly vacuolate cells surrounding a tiny vascular bundle. This has a group of extremely thin walled xylem elements surrounded by two to three groups of functioning phloem elements. The young axial epidermis contains chloroplasts. The cell walls seem adapted to water imbibition. Emptying of cell contents combined with development of ‘endodermal’ wall foldings may suggest recycling of nutrients from the wilting end to the apical part. The single celled xylem strand transforms into a lacuna.
Ultrastructure and Lectin Binding of Human Testicular Embryonal Carcinoma. R. MALMI,*t K. FROJDMAN,t P.-L. KELLOKUMPU-LEHTINEN4 K.-O. SODERSTROM* and L. J. PELLINIEMI,t *Department of Pathology, tLaboratory ofElectron Microscopy and
~Department of Radiotherapy, University of Turku, Turku, Finland Human embryonal carcinoma of the testis in one patient was analysed ultrastructurally and by lectin histochemistry. The heterogeneity of the tumour cells ranged from differentiated cells with extensively developed endoplasmic reticulum, many Golgi lamellae and microvilli to poorly differentiated cells with many ribosomes, but little endoplasmic reticulum and a few Golgi complexes. The nuclei were irregular and contained numerousnucleoli. Mitochondria with dilated cristae and large vesicles were observed in the cytoplasm. Among the FITC-conjugated lectins, which labelled only some tumour cells, the distribution of PNA along free cellular margins suggested functional differences in cancer cells. The intense labelling of all cells by WGA and RCA I showed the high content of sialic acid and galactose residues, and the presence of polymannosyl cores in carbohydrate chains was demonstrated by the heterogeneous, often granular Con A binding. Alpha-foetoprotein and /3-human chorionic gonadotrophin, both glycoproteins known to interact with Con A, were not elevated in pre- and postoperative sera of this patient. Despite the presence of poorly differentiated cells, the clinical outcome of this non-metastatic cancer has been good with a complete remission after orchidectomy and without any adjuvant therapy, during the present 5-year follow-up period. Regardless of the germ cell origin, the present embryonal carcinoma cells differed from normal germ cells. The distribution of glycoconjugates was also different from that of testicular carcinoma in situ germ cells which share morphological features and the pattern of glycosylation with seminoma cells.
Structure and Composition of Severely Defective Eggshells of Larus ridibundus. JUHA and ULLA AHONEN,t *Depart ment of Zoology and ~Department of Botany, University of Oulu, Oulu, Finland Cracked eggs which had dried and been destroyed during incubation were found in nests of 12 species of shore birds on the Finnish coast of the Bothnian Bay, where about 5600 nests of 40 species were inspected in 1987 as part of the Finnish Acidification Project (HAPRO). Pieces of normal and defective eggshells of the black-headed gull, MARKKOLA,* EIN0 MERILA,* ANNAMARI MARKKOLAt
SCANDEM-90
165
Larus ridibundus, were boiled in 2.5% NaOH to remove the membranes, dried and carbon-coated. The structure and composition of the eggshells was studied using SEMEDS. The main difference between the normal and defective eggshells was in their thickness, the defective ones being distinctly thinner than the normal ones and varying irregularly in thickness. The outer surface was very rough—composed of Ca-carbonate crystals forming roundish lumps of varying size compared with the evenly smooth surface of the normal eggs. No difference in composition was found between the defective and normal eggshells in EDS analyses. Calcium and phosphorus were the main elements, and no aluminium or heavy metals were found in either type ofeggshell. The composition was relatively homogeneous throughout the whole thickness of the shell in both types. Defectiveeggshell formation attributable to aluminium in the bone marrow tissue of the parent birds has been observed in some passerines in Swedish Lapland, where acidification was thought to be a possible cause. The physiology of eggshellformation in the avian shell gland and the role of toxic elements in this could be an object for further study. Immunocytochemical Localization of an Aspartic Proteinase and a Cysteine Proteinase in Germinating Barley Grain. SALLA MARTTILA and ANITA MIKKONEN, University of Jyvaskyla, Department of Biology, Vapaudenk. 4, SF-40100 Jyváskyla, Finland The storage proteins of barley grains are mainly localized in the non-living starchy endosperm. Acid proteinases start the hydrolysis of these insoluble proteins producing soluble peptides. The living organs of the grain, the scutellum and aleurone layer, correspond to the synthesis of proteolytic enzymes. In this work, the appearance and transport of two acid proteinases, an aspartic proteinase and a cysteine proteinase, were studied immunocytochemically both at tissue and subcellular levels. Aspartic proteinase activity is low in resting barley grains, and it does not increase significantly during germination. Light microscopy results (paraffin sections of whole grains) using the immunogold method show that in the beginning of germination this enzyme is localized mainly in the scutellum. After germination of 3 days it also appears almost all over the aleurone layer. Although the labelling of the enzyme increased during germination no secretion into the starchy endosperm was observed. The other acid proteinase, cysteine proteinase, may be synthesized de novo during germination. This enzyme appeared first in the scutellum, from where it was secreted in the course of germination into the starchy endosperm. Later on the enzyme was also observed in the aleurone layer, where the labelling was first strongest near the scutellar tissue. Preliminary results from electron microscopy (cryosections labelled by the protein Aimmunogold method) suggest that these acid proteinases are localized subcellularly in the protein bodies of the scutellum. The mechanism of the secretion and transport require more electron microscopic studies. These results show that cysteine proteinase is secreted into the starchy endosperm. This confirms the suggestion that the enzyme plays a major role in the mobilization of storage proteins. Aspartic proteinase, on the contrary, seems to take part in the hydrolysis of proteins in the living organs, the scutellum and aleurone layer. Mechanisms of Lipofuscinogenesis: Effect of the Inhibition of Lysosomal Proteases and Lipases under Varying Concentrations of Ambient Oxygen in Cultured Rat Neonatal Myocardial Cells. M. R. MARZABADI, B.-A. FREDRIKSSON and U. T. BRUNK, Department of Pathology, University of Linkôping, S-581 85 Linkoping, Sweden This study demonstrates enhanced lipofuscinogenesis in cultured neonatal rat cardiac myocytes when exposed to inhibitors of lysosomal thiol-proteinases and
SCANDEM-90
The seeds seem to be adapted to wind dispersal and rapid water uptake: the outer epidermal walls are invaginated into the epidermal cells in dry seeds, but bulge in moistened seeds. The remaining part of the seed coat consists of two different single ‘palisade layers’ and a multilayer of compressed parenchyma cells. The endosperm has an outer aleuron layer followed by starch filled cells. The outer cells walls are covered by a cuticle. The other walls are gelatinous and absorb water readily. A dry seed is very light. The embryo cells are stored with lipids and protein. An indication of small cell bridges interconnecting the coils of the embryo is an interesting feature. The newly germinated seedling has a tuberous radicular end lacking a root meristem and a fihiform axis lacking cotyledons, but with a greenish apex. The tuberous end consists of large highly vacuolate cells surrounding a tiny vascular bundle. This has a group of extremely thin walled xylem elements surrounded by two to three groups of functioning phloem elements. The young axial epidermis contains chloroplasts. The cell walls seem adapted to water imbibition. Emptying of cell contents combined with development of ‘endodermal’ wall foldings may suggest recycling of nutrients from the wilting end to the apical part. The single celled xylem strand transforms into a lacuna.
Ultrastructure and Lectin Binding of Human Testicular Embryonal Carcinoma. R. MALMI,*t K. FROJDMAN,t P.-L. KELLOKUMPU-LEHTINEN4 K.-O. SODERSTROM* and L. J. PELLINIEMI,t *Department of Pathology, tLaboratory ofElectron Microscopy and
~Department of Radiotherapy, University of Turku, Turku, Finland Human embryonal carcinoma of the testis in one patient was analysed ultrastructurally and by lectin histochemistry. The heterogeneity of the tumour cells ranged from differentiated cells with extensively developed endoplasmic reticulum, many Golgi lamellae and microvilli to poorly differentiated cells with many ribosomes, but little endoplasmic reticulum and a few Golgi complexes. The nuclei were irregular and contained numerousnucleoli. Mitochondria with dilated cristae and large vesicles were observed in the cytoplasm. Among the FITC-conjugated lectins, which labelled only some tumour cells, the distribution of PNA along free cellular margins suggested functional differences in cancer cells. The intense labelling of all cells by WGA and RCA I showed the high content of sialic acid and galactose residues, and the presence of polymannosyl cores in carbohydrate chains was demonstrated by the heterogeneous, often granular Con A binding. Alpha-foetoprotein and /3-human chorionic gonadotrophin, both glycoproteins known to interact with Con A, were not elevated in pre- and postoperative sera of this patient. Despite the presence of poorly differentiated cells, the clinical outcome of this non-metastatic cancer has been good with a complete remission after orchidectomy and without any adjuvant therapy, during the present 5-year follow-up period. Regardless of the germ cell origin, the present embryonal carcinoma cells differed from normal germ cells. The distribution of glycoconjugates was also different from that of testicular carcinoma in situ germ cells which share morphological features and the pattern of glycosylation with seminoma cells.
Structure and Composition of Severely Defective Eggshells of Larus ridibundus. JUHA and ULLA AHONEN,t *Depart ment of Zoology and ~Department of Botany, University of Oulu, Oulu, Finland Cracked eggs which had dried and been destroyed during incubation were found in nests of 12 species of shore birds on the Finnish coast of the Bothnian Bay, where about 5600 nests of 40 species were inspected in 1987 as part of the Finnish Acidification Project (HAPRO). Pieces of normal and defective eggshells of the black-headed gull, MARKKOLA,* EIN0 MERILA,* ANNAMARI MARKKOLAt
SCANDEM-90
165
Larus ridibundus, were boiled in 2.5% NaOH to remove the membranes, dried and carbon-coated. The structure and composition of the eggshells was studied using SEMEDS. The main difference between the normal and defective eggshells was in their thickness, the defective ones being distinctly thinner than the normal ones and varying irregularly in thickness. The outer surface was very rough—composed of Ca-carbonate crystals forming roundish lumps of varying size compared with the evenly smooth surface of the normal eggs. No difference in composition was found between the defective and normal eggshells in EDS analyses. Calcium and phosphorus were the main elements, and no aluminium or heavy metals were found in either type ofeggshell. The composition was relatively homogeneous throughout the whole thickness of the shell in both types. Defectiveeggshell formation attributable to aluminium in the bone marrow tissue of the parent birds has been observed in some passerines in Swedish Lapland, where acidification was thought to be a possible cause. The physiology of eggshellformation in the avian shell gland and the role of toxic elements in this could be an object for further study. Immunocytochemical Localization of an Aspartic Proteinase and a Cysteine Proteinase in Germinating Barley Grain. SALLA MARTTILA and ANITA MIKKONEN, University of Jyvaskyla, Department of Biology, Vapaudenk. 4, SF-40100 Jyváskyla, Finland The storage proteins of barley grains are mainly localized in the non-living starchy endosperm. Acid proteinases start the hydrolysis of these insoluble proteins producing soluble peptides. The living organs of the grain, the scutellum and aleurone layer, correspond to the synthesis of proteolytic enzymes. In this work, the appearance and transport of two acid proteinases, an aspartic proteinase and a cysteine proteinase, were studied immunocytochemically both at tissue and subcellular levels. Aspartic proteinase activity is low in resting barley grains, and it does not increase significantly during germination. Light microscopy results (paraffin sections of whole grains) using the immunogold method show that in the beginning of germination this enzyme is localized mainly in the scutellum. After germination of 3 days it also appears almost all over the aleurone layer. Although the labelling of the enzyme increased during germination no secretion into the starchy endosperm was observed. The other acid proteinase, cysteine proteinase, may be synthesized de novo during germination. This enzyme appeared first in the scutellum, from where it was secreted in the course of germination into the starchy endosperm. Later on the enzyme was also observed in the aleurone layer, where the labelling was first strongest near the scutellar tissue. Preliminary results from electron microscopy (cryosections labelled by the protein Aimmunogold method) suggest that these acid proteinases are localized subcellularly in the protein bodies of the scutellum. The mechanism of the secretion and transport require more electron microscopic studies. These results show that cysteine proteinase is secreted into the starchy endosperm. This confirms the suggestion that the enzyme plays a major role in the mobilization of storage proteins. Aspartic proteinase, on the contrary, seems to take part in the hydrolysis of proteins in the living organs, the scutellum and aleurone layer. Mechanisms of Lipofuscinogenesis: Effect of the Inhibition of Lysosomal Proteases and Lipases under Varying Concentrations of Ambient Oxygen in Cultured Rat Neonatal Myocardial Cells. M. R. MARZABADI, B.-A. FREDRIKSSON and U. T. BRUNK, Department of Pathology, University of Linkôping, S-581 85 Linkoping, Sweden This study demonstrates enhanced lipofuscinogenesis in cultured neonatal rat cardiac myocytes when exposed to inhibitors of lysosomal thiol-proteinases and