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Biomedical subjects

E Anderson

Publications and source records attributed to E Anderson.

At least 199 records · Page 11Linked to original sources
PubMed1980

The cytoplasmic filamentous network in cultured ovarian granulosa cells.

We have utilized a cracking procedure followed by a rotary shadow technique to examine the ultrastructure of cultured ovarian granulosa cells. We have demonstrated that the structures observed are not artifacts of fixation or cracking by generating equivalent images following freezing and deep etching as well as by fixation prior to cracking. The cytoplasm of granulosa cells exhibits a complex cytoskeletal lattice composed of many 40-55 nm filaments. This filamentous network is continuous with the plasma membrane and appears to incorporate all formed elements within the cytoplasm. Filaments are organized in three ways: first, in large bundles, second, in individual filaments that are in direct association with organelles, and third, in a complex branching and anastomosing configuration. S-1 decoration revealed that the predominant filament species is action.

Actins↗
PubMed1979

Hormonal modulation of ovarian interstitial cells with particular reference to gap junctions.

Thin-section and freeze-fracture studies on the rat ovarian interstitial cells revealed reductions in the size and the number of gap junctions after pituitary ablation. Small gap junctions, however, persist as long as 90 days after hypophysectomy even though regressive cytoplasmic changes are completed 75 d earlier. Administration of exogenous human chorionic gonadotrophin (HCG) results in the restoration of the normal interstitial cell morphology which is accompanied by amplification of junctional membrane. Within 24 h of hormone application, gap junction growth is characterized by the appearance of formation plaques. These studies suggest that the effect of hormone on interstitial cell gap junctions is to modulate the junctional surface area.

Animals↗
PubMed1979

Epidermal growth factor in the submandibular gland and serum of mice with muscular dystrophy: chemical properties in dilute gland extracts.

Epidermal growth factor (EGF) has been measured in extracts of submandibular glands from mice with hereditary muscular dystrophy. RIA results show that adult male and female dystrophic mice have significantly less submandibular gland EGF than do unafflicted controls. Despite the differences in gland content of the protein, serum levels of EGF are similar in both dystrophic and control animals. Furthermore, submandibular gland concentrations of amylase are normal in the dystrophic mice, indicating that not all proteins synthesized by the glands are affected. Gel filtration studied reveal that the elution properties of EGF in extracts of glands from dystrophic and control animals are indistinguishable. Unexpectedly, the chromatographic profiles indicate that most of the EGF in gland extracts elutes as a low molecular weight protein when the molecule is studied at low, biologically active concentrations; only a small portion of the protein is associated with a high molecular weight complex. Under the same experimental conditions, submandibular gland nerve growth factor maintains its association with other components in a high molecular weight form.

Amylases↗
PubMed1978

A correlative microscopical analysis of differentiating ovarian follicles of mammals.

The mammalian ovary has been studied by optical microscopy and by scanning and transmission electron microscopy with the purpose of presenting an integrated view of the differentiating mammalian follicle. During follicular development, changes in the granulosa cells are particularly noteworthy and include dramatic modifications in cell shape coincident with antrum formation. The cytoplasmic processes of those granulosa cells immediately surrounding the oocyte, as well as the more peripheral granulosa cells comprising a second and third layer, traverse the zona pellucida, infrequently interdigitate with the microvilli of the egg, and make both desmosomal and gap junction contacts with the oocyte. The zona pellucida is thus distinguished by numerous fenestrations of varying diameters. The membrana limitans (basal lamina) is a bipartite structure composed of (a) a homogenous stratum upon which the peripheral layer of granulosa cells rests, and (b) an outer region of collagen-like fibers. The specific advantages and limitations of the different methodologies utilized to study folliculo-genesis are discussed.

Animals↗
PubMed1978

Self-observation and self-reinforcement as sources of self-control in children.

Eight fifth- and sixth-grade black males engaged in a set of single-subject, multiple-baseline studies to determine the relative effects of self-observation and self-reinforcement. A black male college student employed the children as research assistants who would study their own behavior. The employer negotiated a series of individualized contracts with each boy. The contracts specified what self-regulation procedures the subject would perform. Overall, the children were more consistent in carrying out their contracts when they were on self-reinforcement than when they were on self-observation. Second, the children were more effective in increasing behavioral deficits than they were in decreasing excesses. Third, self-reinforcement was clearly a superior means of improving their own behavior than was self-observation.

Black or African American↗
PubMed1978

Enzymic oxidation alpha to the acetylenic group in the metabolism of N-(5-pyrrolidinopent-3-ynyl)-succinimide (BL 14) in vitro.

1. The product of alpha-acetylenic oxidation of N-(5-pyrrolidinopent-3-ynyl)-succinimide (BL 14) by rat liver preparations was identified as N-(5-pyrrolidino-2-hydroxypent-3-ynyl)succinimide, by mass spectral analysis of metabolites of deuterium-labelled and non-labelled substrate. 2. The synthesis and physicochemical characteristics of the metabolite are reported. 3. Substantial amounts of the metabolite were obtained in preparations from phenobarbital-treated rats, while only minute amounts were formed by non-induced preparations. 4. Evidence for the involvement of an inducible cytochrome P-450 system in effecting this alpha-acetylenic oxidation is presented.

Alkynes↗
PubMed1978

Stroke rehabilitation: evaluation of its quality by assessing patient outcomes.

A modified version of an outcome-oriented quality-assurance system was used to assess the care received by patients, aged 21 to 60 years, with completed stroke, who had participated for at least three weeks in a rehabilitation program. Care for 110 patients was evaluated by comparing actual results with a set of standards for outcomes produced by practicing rehabilitation professionals using small-group estimation techniques. Outcomes were better than estimated, standards having indicated that 29% of patients should be capable of self-care, while actually 43% were. When 50 of the 110 outcomes were individually investigated; only 5% of the total study population were probably not functioning at an optimal level, and 3% more might reach optimal functioning if existing follow-up procedures were extended and made more routine. Since only an estimated 3 to 6 cases per year would be affected, the cost of instituting such care would not be justified. Participants concluded that assessment of outcomes justified continuation on the existing processes for stroke rehabilitation.

Adult↗
PubMed1977

Microtubule and microfilament rearrangements during capping of concanavalin A receptors on cultured ovarian granulosa cells.

Thin-section electron microscope analysis of rat and rabbit-cultured granulosa cells treated with concanavalin A (Con A) at 37 degrees C revealed coordinated changes in the cytoplasmic disposition of microfilaments, thick filaments, and microtubules during cap formation and internalization of lectin-receptor complexes. Con A-receptor clustering is accompanied by an accumulation of subplasmalemmal microfilaments which assemble into a loosely woven ring as patches of receptor move centrally on the cell surface. Periodic densities appear in the microfilament ring which becomes reduced in diameter as patches coalesce to form a single central cap. Microtubules and thick filaments emerge associated with the capped membrane. Capping is followed by endocytosis of the con A-receptor complexes. During this process, the microfilament ring is displaced basally into the cytoplasm and endocytic vesicles are transported to the paranuclear Golgi complex along microtubules and thick filaments. Eventually, these vesicles aggregate near the cell center where they are embedded in a dense meshwork of thick filaments. Freeze-fracture analysis of Con A-capped granulosa cells revealed no alteration in the arrangement of peripheral intramembrane particles but large, smooth domains were conspicuous in the capped region of the plasma membrane. The data are discussed with reference to the participation of microtubules and microfilaments in the capping process.

Animals↗