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G C GODMAN

Publications and source records attributed to G C GODMAN.

At least 19 recordsLinked to original sources
PubMed1964

ON THE SITE OF SULFATION IN COLONIC GOBLET CELLS.

The location of bound S(35) in the goblet cell of the rat colon at time points from 2 to 60 minutes after administration of S(35) as sodium sulfate has been observed in vivo and in vitro by radioautographic techniques. Grains were first observed by electron microscopy over the stacked lamellae of the paranuclear part of the Golgi apparatus. The label was subsequently found associated with the supranuclear Golgi lamellae and was then seen associated with the smooth membranes limiting the mucin granules in the goblet. Finally, between (1/2) and 1 hour, the secreted mucus product in the crypts became radioactive. Neither mitochondria nor the endoplasmic reticulum was labeled. It is concluded that the Golgi apparatus is the organelle in which sulfation occurs.

Animals↗
PubMed1964

ON THE SITE OF SULFATION IN THE CHONDROCYTE.

As observed autoradiographically in the cartilage of embryonic rats, radiosulfate is bound and concentrated only in vesicles of the juxtanuclear Golgi apparatus of secreting chondrocytes within 3 minutes of its presentation. From this area, vacuoles migrate peripherally and lodge in the subcortex; their sulfated contents are thence discharged via stomata to the extracellular matrix. The label, apparently often associated with microvesicles at 10 and 20 minutes, is subsequently localized in the dense contents of the larger vacuoles. Bound radiosulfate is not detectable in other organelles. It is concluded that the vesicular component of the Golgi apparatus is the actual site of sulfation. Intracellular hyaluronidase-sensitive metachromatic granules are found chiefly at the cell periphery or mantle, rarely juxtanuclear in the main Golgi zone.

Autoradiography↗
PubMed1961

Structure and development of viruses as observed in the electron microscope. VI. ECHO virus, type 9.

Sequential stages in the development and release of ECHO 9 virus have been illustrated and described. It is suggested that viral particles differentiate and become oriented in columns upon a fine filamentous lattice at cytoplasmic template sites which are distinct from the endoplasmic reticulum. Subsequently, virus is dispersed in the peripheral cytoplasm and gains egress from the cell through rents in the plasma membrane. Complete cellular disruption with viral release may supervene. The virus consists of a 13 to 15 mmicro dense core and a poorly defined outer membrane, 22 to 24 mmicro in diameter. Incomplete forms, lacking the core, are observed in the cytoplasm but have not been seen in the extracellular space.

Animals↗
PubMed1960

A correlative study by electron and light microscopy of the development of type 5 adenovirus. I. Electron microscopy.

Stages in the nuclear changes consequent to infection with type 5 adenovirus are shown and described. Viral development seems to be confined to the nucleus where characteristic particles are found. The shape of the intracellular virus depends upon the method of preservation employed, appearing spherical after osmium tetroxide or freezing-substitution, occasionally exhibiting angulated faces after formalin and often assuming an hexagonal profile after potassium permanganate. The non-viral crystals are encountered in zones of low density, and it is suggested that crystallization results from the accumulation of protein in these areas. An hypothesis is presented to explain why these crystals, in contrast to the insect polyhedra, contain few viral particles.

Adenoviridae↗
PubMed1960

A correlative study by electron and light microscopy of the development of type 5 adenovirus. II. Light microscopy.

The evolution of the intranuclear lesion produced by type 5 adenovirus in HEp-2 and HeLa cells is described as seen in the light microscope and the bodies formed in the course of the infection characterized histochemically. Some 12 hours after infection acidophilic protein bodies, without appreciable nucleic acid, first appear in the nucleus and coalesce into a network. Within or in association with this material, DNA-containing masses (viral aggregates) are formed which rapidly increase in amount and then coalesce. At the same time, a protein is produced, histochemically different from that of the acidophilic or basophilic structures mentioned, within the infected nucleus, which constitutes a matrix within which regular cytstals of a protein, (presumably non-viral) materialize. These structural and histochemical features are correlated with details which have been observed in parallel studies with the electron microscope.

Adenoviridae↗
PubMed1960

Chondrogenesis, studied with the electron microscope.

The role of the cells in the fabrication of a connective tissue matrix, and the structural modifications which accompany cytodifferentiation have been investigated in developing epiphyseal cartilage of fetal rat by means of electron microscopy. Differentiation of the prechondral mesenchymal cells to chondroblasts is marked by the acquisition of an extensive endoplasmic reticulum, enlargement and concentration of the Golgi apparatus, the appearance of membrane-bounded cytoplasmic inclusions, and the formation of specialized foci of increased density in the cell cortex. These modifications are related to the secretion of the cartilage matrix. The matrix of young hyaline cartilage consists of groups of relatively short, straight, banded collagen fibrils of 10 to 20 mmicro and a dense granular component embedded in an amorphous ground substance of moderate electron density. It is postulated that the first phase of fibrillogenesis takes place at the cell cortex in dense bands or striae within the ectoplasm subjacent to the cell membrane. These can be resolved into sheaves of "primary" fibrils of about 7 to 10 mmicro. They are supposedly shed (by excortication) into the matrix space between the separating chondroblasts, where they may serve as "cores" of the definitive matrix fibrils. The diameter of the fibrils may subsequently increase up to threefold, presumably by incorporation of "soluble" or tropocollagen units from the ground substance. The chondroblast also discharges into the matrix the electrondense amorphous or granular contents of vesicles derived from the Golgi apparatus, and the mixed contents of large vacuoles or blebs bounded by distinctive double membranes. Small vesicles with amorphous homogeneous contents of moderate density are expelled in toto from the chondroblasts. In their subsequent evolution to chondrocytes, both nucleus and cytoplasm of the chondroblasts undergo striking condensation. Those moving toward the osteogenic plate accumulate increasingly large stores of glycogen. In the chondrocyte, the enlarged fused Golgi vesicles with dense contents, massed in the juxtanuclear zone, are the most prominent feature of the cytoplasm. Many of these make their way to the surface to discharge their contents. The hypertrophied chondrocytes of the epiphyseal plate ultimately yield up their entire contents to the matrix.

Animals↗
PubMed1957

A cytochemical study of the L. E. bodies of systemic lupus erythematosus. I. Nucleic acids.

The composition, with respect to nucleic acids, of the L.E. bodies resulting from the action of the plasma of patients with systemic lupus erythematosus on substrate leukocyte nuclei in different kinds of preparations was compared microspectrophotometrically with that of control lymphocyte nuclei. Binding of the basic dye methyl green to DNA was uniformly found to be depressed in L.E. bodies as compared with control nuclei. Since Feulgen-revealed DNA, which served as a standard of reference, was relatively unchanged in amount, the Feulgen:methyl green ratios of L.E. bodies were higher than those of lymphocyte nuclei. Acetylation, which covers basic groups of proteins, was found to increase methyl green uptake by DNA of L.E. bodies to values approximating those of control nuclei, with consequent revision, after acetylation of the Feulgen: methyl green ratios of L.E. bodies to values similar to those of lymphocyte nuclei. Ribonuclease was found to reduce methyl green staining; extraction with dilute acid had little effect. These data have been interpreted to indicate (a) the presence in L.E. bodies of DNA-associated proteins whose basic groups compete with the cationic dye for binding sites of DNA and so inhibit methyl green staining, and (b) the DNA itself is not detectibly altered in state or degree of polymerization. Photometric comparison of the mean Feulgen-stainable DNA content per L.E. body with that of control nuclei showed that DNA is not lost in the L.E. transformation of nuclei.

Acetylation↗
PubMed1957

A cytochemical study of the L. E. bodies of systemic lupus erythematosus. II. Proteins.

Microspectrophotometric comparison of lymphocyte nuclei and free L.E. bodies which are derived from them show a more than twofold average increase in the latter of protein basic groups revealed by naphthol yellow S binding, and tyrosine residues demonstrated by the Millon reaction. The alkaline fast green method for histones and the Sakaguchi reaction for arginine residues suggest that there is a marked loss and ultimate disappearance of histones in the course of formation of the L.E. body from a nucleus. It is postulated that the L.E. transformation entails influx of protein normally foreign to the nucleus, displacement of histone from combination of DNA, and association of the DNA with the new protein which is then responsible for masking the anionic groups of DNA.

Arginine↗
PubMed1957

Phase contrast and interferometric microscopy of the L. E. cell phenomenon.

Alterations in the cellular morphology of polymorphonuclear leukocytes and lymphocytes under the influence of serum from patients having disseminated lupus erythematosus were observed under the phase contrast microscope. These changes appear to involve the cell nucleus without significant visible incorporation of cytoplasm. In the formation of the L.E. body, there is a loss of internal nuclear structure and a subsequent nuclear swelling and extrusion of the nuclear contents from the cell to form the free L.E. body. The possible incorporation of cytoplasmic substance cannot alone account for the large mass of the L.E. body as contrasted with the parent nucleus or nuclear lobe. Measurements of dry mass by means of the interference microscope show a two and one-half-fold increment in dry mass in L.E. bodies compared to parent lymphocyte nuclei. This confirms previous cytochemical studies, and establishes that an influx of protein into the leukocyte nucleus is an integral part of the L.E. phenomenon. That the accumulation of extraneous protein within the L.E. body is simultaneous with or subsequent to a disruption of the normal structure of the leukocyte nucleus is apparent from these studies, but the pathogenesis of this alteration is as yet unknown.

Cell Nucleus↗