Ultrastructural study of ascoma and ascospore development in Ophiostoma distortum and Ophiostoma minus

1991 ◽  
Vol 69 (11) ◽  
pp. 2529-2538 ◽  
Author(s):  
P. W. J. van Wyk ◽  
M. J. Wingfield
Keyword(s):  
Key Words ◽  
Ultrastructural Study ◽  
Secondary Wall ◽  
Outer Wall ◽  
Ultrastructural Level ◽  
Uniform Thickness ◽  
Central Cluster ◽  
Ultrastructural Studies ◽  
Ascospore Development ◽  
Development And Evolution

The development of the ascoma, ascus, and elongated ascospores in Ophiostoma distortum and Ophiostoma minus was studied at the ultrastructural level and compared with that of other related Ascomycetes. The organization of the centra in O. distortum and O. minus differed considerably. In O. distortum, asci were irregularly arranged in clusters that occurred in the lower half along the periphery of the ascoma. In O. minus, asci developed from a central cluster at the base of the ascoma. The asci extended upwards and outwards from the base. Ascospore development in both fungi commenced with the formation of double, delimiting membranes in the ascus. Between these membranes ascospore walls developed, consisting of the primary and secondary wall. In comparison with other species having similar ascospores, differences were found between the number of wall layers of the ascospores and formation of the outer wall layers. The secondary wall and perisporic sac of O. minus were smooth and of uniform thickness, whereas the inner layer of the secondary wall in O. distortum was thickened and distorted in certain areas. It is suggested that additional ultrastructural studies should be undertaken to provide a better understanding of the development and evolution of ascospore sheaths in Ceratocystis sensu lato. Key words: Ceratocystis, elongated ascospores, centrum.

Ascospore development in Ophiostoma piceae

1992 ◽  
Vol 70 (11) ◽  
pp. 2170-2176 ◽  
Author(s):  
P. W. J. van Wyk ◽  
M. J. Wingfield
Keyword(s):  
Key Words ◽  
Secondary Wall ◽  
Ophiostoma Piceae ◽  
Ascospore Development

The development of ascoma, ascus, and ascospore in Ophiostoma piceae was studied ultrastructurally and compared with that of other Ascomycetes. Ascospore delimitation commenced with the formation of double delimiting membranes in the ascus. The ascospore wall, consisting of the primary and secondary walls, was deposited between these membranes. The elongate ascospores of O. piceae differed from other species having similarly shaped ascospores, with respect to the shape and arrangement of asci in the ascoma, the number of wall layers of the ascospore, and formation of the secondary wall. Asci in O. piceae are spindle shaped, arranged along the periphery of the ascomatal wall. The ascospores have three layered walls, whereas some other species in Ceratocystis s.l. also with elongated ascospores probably have only two wall layers. Key words: Ophiostoma, elongated ascospores, sheaths, centrum.

Spore wall ontogeny in Pseudoplectania nigrella and Plectania nannfeldtii (Ascomycotina, Pezizales)

1995 ◽  
Vol 73 (11) ◽  
pp. 1761-1767 ◽  
Author(s):  
Li-Tzu Li ◽  
James W. Kimbrough
Keyword(s):  
Key Words ◽  
Light Microscope ◽  
Secondary Wall ◽  
Spore Wall ◽  
Wall Layer ◽  
Ultrastructural Studies ◽  
Blue Stain ◽  
Spore Wall Ornamentation

Pseudoplectania and Plectania currently belong to the Sarcosomataceae, tribe Sarcosomateae, a group with members lacking cyanophilic spore markings (absorbing a blue stain). The two genera are morphologically similar in having blackish discoid-shaped apothecia but differ in having globose and ellipsoid spores, respectively. Ultrastructural studies show that ascospores of Pseudoplectania nigrella (Pers. ex Fr.) Fuckel lack a secondary wall layer. On the contrary, Plectania nannfeldtii Korf has secondary spore wall ornamentation that is cyanophilic under a light microscope. The data suggest retention of Pseudoplectania nigrella in the Sarcosomateae; however, the position of certain species of Plectania needs to be reevaluated. Key words: Pezizales, Plectania, Pseudoplectania, Sarcosomataceae, spore ontogeny, ultrastructure.

Glycogen in guinea pig neutrophils: Ultrastructural study of neutrophils at the intradermal site of BCG injection

1983 ◽  
Vol 41 ◽  
pp. 726-727
Author(s):  
Corazon D. Bucana
Keyword(s):  
Bone Marrow ◽  
Guinea Pig ◽  
Electron Density ◽  
Peritoneal Cavity ◽  
Ultrastructural Study ◽  
Guinea Pigs ◽  
Random Distribution ◽  
Glycogen Content ◽  
Polymorphonuclear Neutrophils ◽  
Ultrastructural Studies

In the circulating blood of man and guinea pigs, glycogen occurs primarily in polymorphonuclear neutrophils and platelets. The amount of glycogen in neutrophils increases with time after the cells leave the bone marrow, and the distribution of glycogen in neutrophils changes from an apparently random distribution to large clumps when these cells move out of the circulation to the site of inflammation in the peritoneal cavity. The objective of this study was to further investigate changes in glycogen content and distribution in neutrophils. I chose an intradermal site because it allows study of neutrophils at various stages of extravasation.Initially, osmium ferrocyanide and osmium ferricyanide were used to fix glycogen in the neutrophils for ultrastructural studies. My findings confirmed previous reports that showed that glycogen is well preserved by both these fixatives and that osmium ferricyanide protects glycogen from solubilization by uranyl acetate.I found that osmium ferrocyanide similarly protected glycogen. My studies showed, however, that the electron density of mitochondria and other cytoplasmic organelles was lower in samples fixed with osmium ferrocyanide than in samples fixed with osmium ferricyanide.

Erythrophagocytosis by Entamoeba histolytica.- Ultrastructural Study

1972 ◽  
Vol 30 ◽  
pp. 156-157 ◽  
Author(s):  
Norberto Treviño ◽  
Alfredo Feria-Velasco ◽  
I. Ruiz de Chávez
Keyword(s):  
Electron Microscopy ◽  
Light Microscopy ◽  
Entamoeba Histolytica ◽  
Ultrastructural Study ◽  
Saline Solution ◽  
Physiological Saline ◽  
Ultrastructural Level ◽  
Hot Plate ◽  
Physiological Saline Solution ◽  
Axenic Conditions

Although erythrophagocytosis by various species of Entamoeba is a well known phenomenon this has not yet been studied in detail at the ultrastructural level. The present work deals with the description of the incorporation process of erythrocytes by trophozoites of E. histolytica. For this study, trophozoites of E. histolytica, HK-9:NIH strain cultured in axenic conditions and washed human erythrocytes were placed on a hot plate at 37°C in physiological saline solution. After 5 minutes, 2.5% glutarldehyde was added and the samples were processed according to conventional techniques for electron microscopy.Based upon light microscopy studies on living trophozoites in contact with erythrocytes, it seems that erythrophagocytosis only takes place in one pole of the parasite.

Histochemical and Ultrastructural Studies of the Digestive Epithelium in a Gastropod Gametolytic Organ

1980 ◽  
Vol 38 ◽  
pp. 568-569
Author(s):  
R. L. Reeder ◽  
S. H. Rogers ◽  
W. A. Shannon
Keyword(s):  
Acid Phosphatase ◽  
Genital Tract ◽  
Reproductive Tract ◽  
Ultrastructural Level ◽  
Conclusive Evidence ◽  
Digestive Organ ◽  
Limited Information ◽  
Ultrastructural Studies ◽  
Morphological Studies

Numerous morphological studies have dealt with the spermatheca of pulmonate gastropods. This globular organ, which is attached to the female portion of the reproductive tract by a long duct in these monoecious animals, has had various functions ascribed to it. Recent histochemical demonstrations of deoxyribonuclease, ribonuclease, protease, and acid phosphatase have provided, however, conclusive evidence that it is a digestive organ for the degradation of superfluous sperm and genital tract secretions. Only limited information concerning the spermatheca is available at the ultrastructural level, a fact providing the stimulus for the present study of this organ in Sonorella santaritana, a desert mountain snail from Arizona.

Ultrastructural Studies of Piscine Erythrocytic Necrosis (PEN) in Atlantic Herring (Clupea harengus harengus)

1978 ◽  
Vol 35 (1) ◽  
pp. 148-154 ◽  
Author(s):  
Paul W. Reno ◽  
Marie Philippon-Fried ◽  
Bruce L. Nicholson ◽  
Stuart W. Sherburne
Keyword(s):  
Electron Microscope ◽  
Key Words ◽  
Clupea Harengus ◽  
Type I ◽  
Atlantic Herring ◽  
Type Ii ◽  
Inclusion Type ◽  
Cytoplasmic Inclusions ◽  
Ultrastructural Studies ◽  
Clupea Harengus Harengus

Erythrocytes of PEN-positive Atlantic herring (Clupea harengus harengus) were examined to determine their ultrastructure. Cytoplasmic inclusions were of two types when observed under the electron microscope. The first type (type I) appeared coarsely granular, electron dense, round, and up to 1.5 μm in diameter. Virions were closely associated with this type of inclusion. The second type of inclusion (type II) had approximately the same appearance as the surrounding cytoplasm, from which it was separated by a discrete membrane, and was variable in size. Virions were not intimately associated with type II inclusions. Virions occurred singly or in clusters within the cytoplasm or in association with type I inclusions and were hexagonal and 145 nm in diameter. Virions were composed of a rigid hexagonal capsid 8 nm wide, a lighter 16-nm region, and a core 100 nm in diameter. The virus of PEN is presumptively classified as an Iridovirus. Key words: ultrastructure, erythrocytes, virology

Ultrastructural and cytological observations of apothecial tissues of Geopyxis carbonaria (Pezizales, Ascomycetes)

1990 ◽  
Vol 68 (2) ◽  
pp. 243-257 ◽  
Author(s):  
James W. Kimbrough ◽  
Jack L. Gibson
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Key Words ◽  
Mother Cell ◽  
Secondary Wall ◽  
Cell Stage ◽  
Wall Structures ◽  
Transmission Electron ◽  
Secondary Wall Formation ◽  
Characteristic Features

Cytological observations are made on apothecial tissues of Geopyxis carbonaria, using transmission electron microscopy. Characteristic features of both the medullary and ectal excipula are examined. Changes in ascus apex and wall structures are examined during ascus ontogeny, especially in relation to operculum position and structure. Ultrastructure of septum configuration is observed and compared in the excipulum, ascogenous hyphae, paraphyses, and at the base of young asci. Ascosporogenesis is observed from the ascus mother cell stage and initial spore delimitation until secondary wall formation. The cytological and ultrastructural observations on this species are discussed in relation to their possible taxonomic or phylogenetic value. Key words: ascosporogenesis, Discomycetes, ascospore ultrastructure, septal ultrastructure, cytochemistry.

scholarly journals Case Report and Ultrastructural Study of Intracranial Embryonal Carcinoma

1978 ◽  
Vol 5 (4) ◽  
pp. 447-450 ◽  
Author(s):  
Gerson Ejeckam ◽  
Margaret G. Norman ◽  
Leslie P. Ivan
Keyword(s):  
Germ Cell ◽  
Ultrastructural Study ◽  
Embryonal Carcinoma ◽  
Secretory Granules ◽  
Germ Cell Tumors ◽  
Cell Types ◽  
Ultrastructural Level ◽  
Embryoid Bodies ◽  
Differentiated Cells ◽  
Intermediate Cells

SUMMARY:A case of a primary intracranial embryonal carcinoma, the first with ultrastructural study, is reported. The tumor was associated with precocious puberty in a 6½-year-old female. Characteristic embryoid bodies were present. At the ultrastructural level three cell types were noted: undifferentiated, differentiated, and intermediate types. The undifferentiated showed scanty cytoplasmic organelles and numerous free polysomes, while the differentiated cells contained well-developed mitochondria, Golgi apparatus, rough endoplasmic reticulum, and some contained secretory granules. The intermediate cells possessed dilated and irregularly-shaped mitochondria but still retained large numbers of free polysomes. The authors suggest that intracranial germ cell tumors be named in conformity with germ cell tumors in other sites, and that terms such as “ectopic pinealoma” and “atypical teratoma of the pineal” be used no longer.

scholarly journals The colleteric glands in Sacculinidae (Crustacea, Cirripedia, Rhizocephala): an ultrastructural study of ovisac secretion

2002 ◽  
Vol 70 (4) ◽  
pp. 229-242 ◽  
Author(s):  
Sven Lange
Keyword(s):  
Ultrastructural Study ◽  
Outer Zone ◽  
Ultrastructural Level ◽  
Mantle Cavity ◽  
Secretory Process ◽  
Egg Masses ◽  
Secretory Epithelium ◽  
Sacculina Carcini

Ovisac secretion by the paired colleteric glands of Sacculina carcini and Heterosaccus dollfusi (Rhizocephala, Sacculinida) was documented and studied at the ultrastructural level. Preparatory to oviposition, the epithelium of each colleteric gland secretes one branched, elastic, transparent ovisac. The ovisac wall consists of a reticulated inner zone, secreted first, and a dense outer zone. After secretion, the ovisac detaches from most of the secretory epithelium but remains anchored proximally in the gland until oviposition ends. The exterior ovisac surface is predominantly smooth and impervious. Proximally, however, the surface is irregular and perforated. During oviposition the eggs enter the paired ovisacs, forcing the ovisacs through the ovipores into the maternal mantle cavity. Simultaneously the ovisac volume increases approximately 100 times. The resulting paired egg masses, branched like the ovisacs, are brooded and ventilated in the mantle cavity. Ovisacs prevent that developing embryos are lost prematurely with the ventilation current. Within two days the egg masses solidify and attach to retinacula in the mantle cavity cuticle. The ovisacs, now probably obsolete, are no longer discernible. The literature on colleteric gland morphology implies that ovisacs are secreted by all Sacculinidae and perhaps other Rhizocephala with colleteric glands. Similarities in both the secretory process and morphology suggest homology between the colleteric glands of Sacculinidae and the oviducal glands of Thoracica (Cirripedia) and between their products.

scholarly journals A new lectin-gold complex for ultrastructural localization of galacturonic acids.

1988 ◽  
Vol 36 (11) ◽  
pp. 1403-1411 ◽  
Author(s):  
N Benhamou ◽  
N Gilboa-Garber ◽  
J Trudel ◽  
A Asselin
Keyword(s):  
Binding Sites ◽  
Ricinus Communis ◽  
Ultrastructural Localization ◽  
Ultrastructural Level ◽  
Gold Complex ◽  
Carbohydrate Binding ◽  
Wheat Coleoptile ◽  
Ultrastructural Studies ◽  
Pectic Substances ◽  
Considerable Loss

We report the development of a cytochemical affinity technique for detection of galacturonic acids at the ultrastructural level. The highly purified gonad lectin from Aplysia depilans (AGL) was tagged with colloidal gold particles and used for labeling carbohydrates in resin-embedded sections of various plant and fungal tissues. Patterns of AGL binding sites were compared to those obtained with a D-galactose-specific lectin, Ricinus communis agglutinin I. Differences in labeling patterns were noted, indicating that the lectins exhibited differential carbohydrate binding. In addition, the considerable loss of labeling over isolated wheat coleoptile walls treated for removal of pectin, after incubation with the AGL-gold complex, strongly suggested an affinity of AGL for pectic substances. A series of cytochemical controls, including sugar inhibition tests, has proven the specificity of the technique and the high affinity of AGL towards galacturonic acids. The potential value of this new lectin for ultrastructural studies on cell wall pectic substances in plant biology and pathology is demonstrated.

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