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Biomedical subjects

K R Stone

Publications and source records attributed to K R Stone.

52 records · Page 3Linked to original sources
PubMed1977

Correlation of apparent molecular weight and antigenicity of viral proteins: an SDS-page separation followed by acrylamide-agarose electrophoresis and immunoprecipitation.

A simple method is described which combines a sodium dodecyl sulfate polyacrylamide gel electrophoresis (SOS-PAGE) in the first demension with a second electrophoresis, at right angles to the first, into an agarose matrix. The proteins, separated by SDS-PAGE, are exposed to appropriate antisera after the second stage electrophoresis and immunoprecipitates form in the agarose corresponding to the relative electrophoretic mobilities of proteins in the first stage SDS-PAGE separation. The method thus provides a simple, reproducible means for correlating antigenicity with apparent molecular weight of proteins. The technique is qualtitative, but requires smaller quantities of antisera than more conventional immunoelectrophoretic methods such as rocket electrophoresis.

Antigens, Viral↗
PubMed1977

Development and application of basic research techniques in bladder cancer research.

The growth of transitional epithelial cells with different growth media and growth supports was examined. Sephadex G-10, Bio-Gel P-20, Bio-Glas-1000, DEAE-Sephadex A-50, DEAE-cellulose, CM-Sephadex C-50, acid-soluble collagen, and immobilized collagen fibers were used to enhance plating efficiency. Acid-soluble collagen layers optimally increased the plating efficiency of primary cultures of bladder carcinoma. Media alterations with serial combinations of fetal calf, newborn calf, calf, bovine, and bull serum with minimum essential medium, Roswell Park Memorial Institute Tissue Culture Medium 1640, Connaught Medical Research Laboratories Medium 1066, Medium 199, Grand Island Biological, National Cancer Tissue Culture 135, 1415, McCoy's 5A, and National Cancer Institute medium were established. No promotion of cell division was noted with any one of these basic medium formulations.

Animals↗
PubMed1977

Heterotransplantation of a human prostatic adenocarcinoma cell line in nude mice.

Nude mice of NIH/Swiss background were utilized for the heterotransplantation of a tissue culture cell line derived from a human prostate adenocarcinoma metastatic to the brain. These cells, which had been grown in vitro for 13 passages, formed solid tumors when injected s.c. into nude mice. The cell line DU 145 has been passaged 60 times in vitro over a period of 18 months. Tumors removed from the mice were serially transplanted to additional mice and reestablished in vitro. Light-microscopic analysis of the tumor grown in nude mice revealed a strong similarity to the patient's metastatic tumor. The ultrastructure of the tumor cells propagated in nude mice was compared to that of the original human tumor cells and to the tissue culture cells, both before and after passage in nude mouse. No major differences were detected. Karyotypic analysis of the tumor cells grown in vitro before mouse passage, grown in nude mouse, and grown in vitro after mouse passage indicated chromosomal identity and consistent marker chromosomes: three large acrocentric chromosomes and metacentric minute chromosomes.

Adenocarcinoma↗
PubMed1976

Scanning electron microscopy of hyperplastic and neoplastic human prostate.

Acinar cells of neoplastic prostate tissues are more heterogeneous in size and shape than benign hyperplastic cells when observed by scanning electron microscopy. Three types of acinar cells are recognizable by surface structure, cells with microvilli, cells without microvilli, and cells with membrane ruffles. The pitted cells previously seen in BPH tissues are probably artifactual. The identity of the crater cells is sitll in question.

Adenocarcinoma↗
PubMed1976

In vitro cultivation of prostatic epithelium.

A tissue culture procedure for in vitro cultivation of human prostatic tissue that utilizes the enzyme collagenase to disrupt the prostate specimen is described. Collagenase effectively disperses the tissue stroma into single cells which are easily separated from the largely intact glandular structures. The isolated glandular fragments then are used to initiate monolayers of prostatic epithelium in vitro.

Cell Separation↗
PubMed1970

Isolation and characterization of two basic internal proteins from the T-even bacteriophages.

Two species of basic internal proteins were found in osmotic shock supernatant solutions of bacteriophages T4B, T4D, T2H, T2L, and T6. The major species of protein isolated had a molecular weight of approximately 21,000 daltons, whereas the minor protein molecular weight was near 9,500 daltons. The two protein species exhibited unique isoelectric points and amino acid compositions. The 21,000-dalton protein of T2L showed major electrophoretic and compositional differences from the other 21,000-dalton proteins isolated. Similarities between the 21,000-dalton proteins and phage lysozyme are discussed.

Amino Acids↗
PubMed1970

Characterization of T-even bacteriophage substructures. I. Tail fibers and tail tubes.

T-even bacteriophages were grown and purified in bulk quantities. The protein coats were disrupted into their component substructures by treatment with 67% dimethyl sulfoxide (DMSO). Tail fibers and tubes were purified on glycerol-CsCl-D(2)O gradients and examined with respect to sedimentation properties, subunit molecular weights, amino acid composition, isoelectric points, and morphology. It was found that intact tail fibers had a sedimentation coefficient of 12 to 13S and that dissociated fibers consisted of three classes of proteins having molecular weights of 150 K +/- 10, 42 K +/- 4, and 28 K +/- 3 daltons. A model was constructed in which the 150-K subunit folded back on itself twice to give a three-stranded rope. Each 150-K subunit then represented a half-fiber and it was proposed that the role of the 42- and 28-K subunits was to hold each half-fiber together as well as serve as a possible link with other substructures. Isoelectric point studies also indicated that there were three different proteins with pI values of 3.5, 5.7, and 8.0. Amino acid analyses indicated that fibers had a composition distinct from other phage substructures. In addition, a striking difference was noted in the content of tryptophan among the phages examined. T4B had three to five times more tryptophan than did T2L, T2H, T4D, and T6. Intact tail tubes had an S(20,w) of 31 to 38S and dissociated tubes consisted of three proteins of molecular weights 57 K +/- 5, 38 K +/- 4, and 25 K +/- 3 daltons. Based on degradation studies with DMSO, it was proposed that these three proteins were arranged in a helical array yielding the tube structure. Isoelectric point studies indicated that there were three major proteins in the tube whose pI values were 5.1, 5.7, and 8.5. No significant differences were observed in the amino acid content of tubes obtained from all the T-even bacteriophages.

Amino Acids↗
PubMed1970

Characterization of T-even bacteriophage substructures. II. Tail plates.

Tail plates obtained from T4D amber mutants were examined with respect to sedimentation behavior, subunit molecular weights, amino acid composition, isoelectric points, and morphology. Intact plates had an S(20,w) of 77S from pH 5 to 9. The only conformational change noted was that below pH 5 tail plates readily dimerized yielding vis-à-vis dimers with an S(20,w) of 124S. Dissociated plates consisted of three major proteins with molecular weights of 53 K +/- 5, 31 K +/- 3, and 17 K +/- 2 daltons. The amino acid analyses indicated that plates had a composition distinct from fibers and tubes and were relatively rich in tryptophan. Degradation studies with dimethyl sulfoxide (DMSO) indicated that tail plates had a unique biological structure. After treatment with DMSO, and to some extent without DMSO, or from lysates of defective mutants, tetrad structures were observed in the electron microscope. These structures had an amino acid content and relative amounts of types of subunits similar but not identical to intact plates. It was proposed that plates were composed of nine such tetrads giving rise to a structure with six- and threefold symmetry.

Amino Acids↗
PubMedDate not supplied

Meniscal regeneration with copolymeric collagen scaffolds. In vitro and in vivo studies evaluated clinically, histologically, and biochemically.

We sought to create a regeneration template for the meniscal cartilage of the knee to induce complete meniscal regeneration, and to develop the technique for implanting the prosthetic appliance in vivo. We designed a resorbable collagen-based scaffold and conducted in vitro and in vivo studies. In vivo, the scaffold was implanted in the knees of immature swine and mature canines and evaluated clinically, histologically, and biochemically. Because the canine stifle joint meniscus is more clinically relevant to the human meniscus, this paper emphasizes those results. We studied 24 mixed breed dogs (14 males and 10 females) with an average weight of 25.5 kg (range, 20 to 35) that were obtained from a USDA-licensed supplier. The dogs were deemed clinically and radiographically skeletally mature. None of the dogs had a preexisting knee joint abnormality. All dogs underwent an 80% subtotal resection of the medial meniscus bilaterally. A collagen template was implanted in one stifle (N = 24). The contralateral side served as a control: 12 dogs had a total resection alone and the other 12 dogs had an immediate replantation of the autologous meniscus. Results were tabulated at 3, 6, 9, and 12 months. At final evaluation, before the animals were euthanized, the results were submitted for statistical analysis as well as histologic and biochemical analyses. The results demonstrated that a copolymeric collagen-based scaffold can be constructed that is compatible with meniscal fibrochondrocyte growth in vitro and in vivo, that does not inhibit meniscal regeneration in an immature pig, and that may induce regeneration of the meniscus in the mature dog.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMedDate not supplied

The frequency of Baker's cysts associated with meniscal tears.

We reviewed the films of 1760 patients who had magnetic resonance image scanning of the knee joint to assess the most common pathologic changes associated with an incidental finding of a Baker's cyst. Of the 1760 knees scanned, Baker's cysts were noted in 238. The cysts were classified as small (55%), medium (30%), or large (15%) and were primarily found on the medial side of the knee (94%). The menisci were evaluated and changes were classified as complete tears, where signal contacts the surface, or degenerative intrasubstance tears. One hundred eleven (47%) complete meniscal tears were found, and 88 (37%) degenerative tears. The majority of tears were found in the posterior horn of the medial meniscus (65 complete tears and 45 degenerative tears). Thus, 199 tears were found in 170 knees, and 106 of the 170 knees (62%) had tears of the posterior horn of the medial meniscus. Baker's cysts are frequent findings on physical examinations and on magnetic resonance imaging scans of the knee. They are thought to be due to intraarticular pathologic changes, usually posterior meniscal tears. This study documents the association between Baker's cysts and meniscal tears and notes that a complete tear is not necessary for the cyst to be present.

Adolescent↗
PubMedDate not supplied

Morphologic and immunologic studies of human prostatic carcinoma.

Benign and malignant prostatic tissue was removed in surgery and partitioned for (a) ultrastructural study, (b) tissue culture, and (c) (c) immunochemical study. Fourteen malignant and 18 benign prostatic cancer specimens were examined by transmission electron microscopy (TEM) for the presence of viruses or virus-like particles. Viruses could not be identified with assurity in thin sections. Acinar cells of normal, benign prostatic hypertrophy (BPH), and neoplastic prostate tissue were examined in the scanning electron microscope and TEM and found to be extremely heterogenous in their surface morphologies. Three major types of surface morphologies were present: microvillous, ruffled, and bare. All three types of cells were present in normal, BPH, and neoplastic acini. A collagenase procedure was utilized to remove the stromal cells from glandular structures prior to in vitro cultivation. Partially purified extracts from 71 human urothelial tumors and 75 human urothelial nontumor tissues were used as competing antigens in competition radioimmunoassay in an effort to detect the presence of one of the structural components of type-C ribonucleic acid viruses, the p30 core protein. The urothelial tumors tested included 42 BPH specimens and 18 prostatic carcinoma specimens. Thirty-eight percent of the prostatic carcinoma tissues and 48% of the BPH tissues demonstrated the presence of a protein antigenically similar to the p30 core protein of an oncogenic RNA virus.

Adenocarcinoma↗