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Biomedical subjects

W A Anderson

Publications and source records attributed to W A Anderson.

At least 127 records · Page 7Linked to original sources
PubMed1979

Myoglobin as an ultrastructural probe for studying permeability of the nephron.

Hemeproteins, like cytochrome c (12,500 M.W.; Karnovsky and Rice, 1969) and myoglobin (17,816 M.W.; Anderson, 1972; Simionescu et al., 1973) are advantageous over the true peroxidases with larger molecular weights (e.g. horseradish peroxidase, ca. 40,000 M.W) as ultrastructural probes in that they do not elicit vascular leakage in the inflammatory response (Cotran and Karnovsky, 1967) and are relatively nontoxic immunologically inert substances. The main disadvantage in using cytochrome c and myoglobin is that they have weak peroxidatic activity compared to the true peroxidases (Nakamura et al., 1960; Keilin, 1961; Kurozimi et al., 1961). These hemeproteins, however, offer the following advantages: 1) they retain sufficient peroxidatic activity after aldehyde-fixation to oxidize 3,3'-diaminobenzidine (DAB), 2) they may be localized by virtue of an insoluble reaction product (osmium black) deposited at the site of hemeprotein immobilization by fixation, and 3) they represent low molecular weight probes. This brief report emphasizes the advantages of myoglobin in the study of glomerular permeability, transport by endocytosis in proximal tubules and translocation of protein in the lower segments of the nephron.

Animals↗
PubMed1979

Effect of concanavalin A dose, unbound concanavalin A, temperature, Ca2+ and Mg2+, and vinblastine on capping of concanavalin A receptors of human peripheral blood lymphocytes.

The capping of Concanavalin A (Con A) receptors induced by Con A was studied using human peripheral blood lymphocytes. The effects of Con A dose (5--100 micrograms/ml), pretreatment at 4 degrees C, unbound Con A, extracellular Ca2+ and Mg2+ and vinblastine were evaluated using Con A-horseradish peroxidase and electron microscopy. Lymphocytes incubated with Con A at 4 degrees C and fixed with glutaraldehyde exhibited Con A-horseradish peroxidase around the entire cell periphery. After raising the temperature to 37 degrees C, the Con A-horseradish peroxidase moved to form a cap at one pole of the cell and subsequently underwent endocytosis. Capping of Con A receptors induced by Con A at 37 degrees C was observed only at low Con A concentrations in the presence of unbound Con A and extracellular Ca2+ and Mg2+. Increased capping was found after pretreatment of cells with Con A at 4 degrees C, removing unbound Con A and/or removing extracellular Ca2+ and Mg2+, and by treatment with vinblastine. Following removal of both unbound Con A and extracellular Ca2+ and Mg2+, the percentage of capped cells at 37 degrees C was the same as on pretreatment at 4 degrees C under the same conditions. While pretreatment at 4 degrees C caused the breakdown of microtubules, removal of unbound Con A and/or extracellular Ca2+ and Mg2+ had no morphological effect on microtubules or microfilaments. Following exposure of lymphocytes to vinblastine and removal of unbound Con A, capping of Con A receptors by Con A was observed in over 90% of cells at all Con A dosages. However, when cells were exposed to vinblastine in the presence of unbound Con A the formation of Con A caps was either partially or completely inhibited.

Calcium↗
PubMed1979

Anticoccidial activity of narasin in battery raised broiler chickens.

The anticoccidial activity of the ionophorus antibiotic narasin was tested against six species of coccidia (Eimeria acervulina, Eimeria mivati, Eimeria maxima, Eimeria necatrix, Eimeria brunetti, and Eimeria tenella) in battery-raised broilers. Feeding ration medicated with 60, 80, or 100 ppm narasin significantly improved weight gains during the periods of D 0 to D7 and D 0 to D 14 (D 0 = day of inoculation with sporulated oocysts), compared with the weight gains in corresponding inoculated groups fed unmedicated feed. A similar protective effect of the medication was seen with feed conversion ratios (feed consumed/bird weight) and coccidiosis-induced mortality. With most species studied, 40 and 60 ppm narasin was not as efficacious as 80 or 100 ppm. The maximum numerial improvement in weight gain and feed conversion ratio was with 80 ppm narasin. Gross intestinal lesion scores were reduced by medication compared with the scores in birds fed unmedicated feed. The overall trend was for a larger reduction in lesion score with higher drug levels. Narasin at 80 or 100 ppm was generally more effective in controlling individual or mixed species infections of coccidia than 99 ppm monensin.

Animals↗
PubMed1978

Characterization of the estrogen-induced uterine peroxidase by microelectrophoresis.

Estrogen-dependent peroxidase from rat uterine fluid has been investigated by microelectrophoretic techniques. The molecular weight of the enzyme has been determined in the range of 100,000 by using polyacrylamide gradient gels in the absence and presence of nonionic and anionic detergent. The isoelectric points are located between pH 4.5 and 5.9. Employing the two-dimensional combination of isoelectric focusing and gel gradient electrophoresis, the enzyme was separated into two subunits, one having a molecular weight of 70,000, the other less than 20,000. The large subunit has slight enzymatic activiy, while the smaller subunit may be responsible for the charge difference in the holoenzyme pattern. The glycoprotein pattern of the uterine fluid peroxidase is further defined by its separation by affinity chromatography using a concanavalin A-Sepharose column and by its susceptibility to neuraminidase treatment.

Animals↗
PubMed1978

Relative mobility of con A and anionic receptor sites on the cell surface of lymphocytes. A quantitative-cytochemical study.

Events following the binding of Concanavalin A and cationized ferritin to the surface of normal human peripheral blood lymphocytes were followed using ultracytochemical methods. In this paper, we described a technique involving microdensitometry, which was employed in order to make a comparative cytochemical quantitation of the dense horseradish peroxidase-diaminobenzidine reaction products representing the states of Concanavalin A receptors under various conditions of distribution and redistribution. The technique presents a direct approach to the analysis of various probes that are currently being employed for studying the nature and distribution of various cell surface components. An attempt was also made to analyze the distribution of anionic sites, and their lateral redistribution is compared with the mobility of Concanavalin A receptors. The data presented suggests an independent mobility of receptors for Concanavalin A and cationized ferritin.

Cell Membrane↗
PubMed1978

Inflammatory cysts of the pelvic peritoneum.

Three young women with abdominal distension due to pelvic masses were investigated using ultrasound and conventional radiographic techniques. While the latter revealed masses of soft tissue density arising from the pelvis and displacing bowel, the sonogram indicated the morphologic features of thin-walled multiloculated cysts. They were located entirely within the peritoneal cavity and contained serous to serosanguineous fluid. The mesholelial lined walls were infiltrated with chronic inflammatory cells and were adherent to chronically inflamed fallopian tubes. Although these acquired cysts are familiar to pathologists and gynecologists, the literature contains little information about them.

Adolescent↗
PubMed1976

Collagenous bone matrix-induced endochondral ossification hemopoiesis.

Transplantation of collagenous matrix from the rat diaphyseal bone to subcutaneous sites resulted in new bone formation by an endochondral sequence. Functional bone marrow develops within the newly formed ossicle. On day 1, the implanted matrix was a discrete conglomerate with fibrin clot and polymorphonuclear leukocytes. By day 3, the leukocytes disappeared, and this event was followed by migration and close apposition of fibroblast cell surface to the collagenous matrix. This initial matrix-membrane interaction culminated in differentiation of fibroblasts to chondroblasts and osteoblasts. The calcification of the hypertrophied chondrocytes and new bone formation were correlated with increased alkaline phosphatase activity and 45Ca incorporation. The ingrowth of capillaries on day 9 resulted in chondrolysis and osteogenesis. Further remodelling of bony trabeculae by osteoclasts resulted in an ossicle of cancellous bone. This was followed by emergence of extravascular islands of hemocytoblasts and their differentiation into functional bone marrow with erythropoietic and granulopoietic elements and megakaryocytes in the ossicle. The onset and maintenance of erythropoiesis in the induced bone marrow were monitored by 59Fe incorporation into protein-bound heme. These findings imply a role for extracellular collagenous matrix in cell differentiation.

Alkaline Phosphatase↗
PubMed1976

Studies on the antitesticular action of DL-6-(N-2-pipecolinomethyl)-5-hydroxy-indane (PMHI) in the rat.

Both prepubertal and adult rats were treated with a single oral dose of either 60 mg or 120 mg of dl-6-(N-pipecolinomethyl)-5-hydroxy indane maleate (PMHI) per kg of body weight. Their testicular weights were drastically reduced compared with those of the controls. A follow-up, beginning on the third day post-treatment and continuing for a period of 50 days, showed that the body weight growth of PMHI-treated rats was not retarded. The hormonal profile indicated that, except for FSH which showed a transitory elevation in PMHI-treated immature rats, the serum levels of LH, estrogen, and testosterone were indistinguishable from those of the controls. Testicular histology revealed that the spermatogenic process in PMHI-treated rats recovered at a dose-related rate. EM sections of testes of adult rats indicated that cytoplasmic vacuolation appeared in the Sertoli cells 5 h post-treatment. The consequent cascade of arrested spermiogenesis included abnormal acrosomal condensation of spermatids and sloughing of polynucleated spermatids. Some spermatocytes also seemed to be affected, but spermatogonia and Leydig cells remained intact. These results indicate the PMHI acts primarily on Sertoli cells and causes arrest in the spermiogenetic stage of the spermatids. At a higher and toxic dose of PMHI, however, the earlier germinal elements might also be affected, due to the extensive damage to the supporting Sertoli cells.

Age Factors↗
PubMed1976

Human transfer factor: fractionation and biologic activity.

Human transfer factor (TF) was fractionated by exclusion chromatography and the fractions were tested for biologic activity in vivo and in vitro. Specific TF activity in vivo was found to reside in the major UV-absorbing peak (Fraction III). Fraction III eluted at 2.7 X V(O) and transferred tuberculin, candida, or KLH-reactivity to previously negative recipients. Fraction III from nonreactive donors was ineffective. When the fractions were tested in vitro, we found that both the mitogenic activity of whole TF and the suppressive activity to mitogen activation when present in TF was found in Fraction I. Fraction III contained components responsible for augmentation of PHA and PWM responses. In addition, Fraction III contained the component responsible for antigen-dependent augmentation of lymphocyte transformation. Fraction IV was suppressive to antigen-induced lymphocyte transformation. These data suggest that TF preparations contain components which can affect immune reactions in both specific and nonspecific ways.

Antigens↗
PubMed1976

Nicotinamide: suppression of lymphocyte transformation with a component identified in human transfer factor.

The component in human transfer factor (TF) (Fraction IV, from exclusion chromatography on Sephadex G-25) responsible for suppression of antigen-induced lymphocyte transformation was previously identified as nicotinamide. Commercially available nicotinamide was subsequently shown to produce suppression of antigen-induced responses in vitro previously observed with TF Fraction IV. Nicotinamide was found to be nontoxic at the highest concentrations employed (10(-2)M) and suppressive over a relatively broad range (10(-5) to 10(-2)M. The suppression appeared to be related to the magnitude of antigen- or mitogen-induced transformation and was apparent even when nicotinamide was added as late as 48 hr after stimulant addition.

Antigens↗
PubMed1975

Estrogen and antagonist-induced structural changes in the cervico-vaginal epithelium of immature rats.

Estrogen enhances proliferation and keratin formation in the cervico-vaginal epithelium of immature rats, whereas the estrogen antagonist, CI-628 (Parke-Davis), represses mitosis and induces mucinogenesis. Combinations of antagonist and estrogen allow differentiation of an epithelium composed of both keratin-forming and mucous cells. Both estrogen and antagonist induce synthesis of a cervico-vaginal endogenous peroxidase in the intermediate and superficial layers of the epithelium. The secreted vaginal mucus of antagonist-treated animals stains intensely for exogenous peroxidase.

Animals↗
PubMed1975

Ultrastructure of the oocytes of the Egyptian sping mouse (Acomys cahirinus).

The oocytes of types 2, 3, 4 and 5 follicles from the normal spiny mouse were examined withe the electron microsome. Multiple juxtanuclear Golgi bodies, mitochondria associated with flattened granular endoplasmic reticulum, and large nucleus are the main features of the type 2 follicle oocyte. The numbers of mitochondria and Golgi apparati increase significantly at later stages. Small mitochondrial aggregates lacking "intermitochondrial cement" are seen in the ooplasm of types 3, 4 and 5 follicles. "Lamellar complexes" comprising two to six elongate flattened rough ER cisternae and intercisternal filaments begin to appear in the occyte of the type 3 follicle. The intercisternal filaments may be observed as punctate-, dashed-, and solid-lines in cross sections. In tangential sections the filaments display a paracrystalline structure. In the type 4 follicle oocytes, the "lamellar complex" becomes more extensive; polysomes and ribosomal fibrils are juxtaposed to the "lamellar complexes." Bundles of ribosomal fibrils are abundant in the ooplasm of the type 5 follicle. The origin of ribosomal filaments and the functional significance of "lamellar complexes" are discussed.

Animals↗
PubMed1975

Endogenous peroxidase: specific marker enzyme for tissues displaying growth dependency on estrogen.

Data derived from a correlated morphological and biochemical study suggest the following: (a) estradiol-17beta, diethylstilbestrol, the estrogen antagonists nafoxidine (Upjohn 11,000), and Parke Davis C1628 induce synthesis of an endogenous peroxidase in the epithelium of target tissues like the vagina, the cervix, the uterus, and in the acinar cells of the estrogen-dependent rat mammary tumor; (b) peroxidase is a "specific" secretory protein of the estrogen-sensitized uterine endometrium; (c) peroxidase synthesis is not a nonspecific response to steroid hormone action, since progesterone and testosterone do not induce its synthesis; (d) endogenous peroxidase is a possible diagnositc protein for the detection of estrogen-dependent growing tissues, including breast cancer; (e) movement of exogenous horseradish peroxidase from the interstitium to the uterine lumina is restricted by tight junctions located at the apices of epithelial cells. Estrogen and antagonists do not appear to influence the transepithelial movement of exogenous peroxidase into the lumen.

Animals↗