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Biomedical subjects

H Busch

Publications and source records attributed to H Busch.

At least 235 records · Page 13Linked to original sources
PubMed1980

Studies on the human tumor nucleolar antigens.

With rabbit antibodies to nuclear 0.01 M Tris-HCl, pH 8, extract or "nucleolar preparations" of human HeLa S3 cells and fluorescein-labeled goat antirabbit antibodies, bright nucleolar immunofluorescence was observed in human adenocarcinomas, squamous cell carcinomas, sarcomas, hematological neoplasms, and other malignant tumors. With these antibodies, nucleolar immunofluorescence was not found in most normal tissue specimens, benign adenomas, hyperplastic tissues, and specimens of inflammatory diseases. A study was made on the presence in benign and malignant breast tumors of a common nucleolar antigen previously found in a broad range of human malignant tumors. Bright nucleolar immunofluorescence was observed in 19/20 (95%) of known breast cancer specimens. In the group of 80 unknown samples in the "blind" study, 75 (94%) were correctly identified as malignant or benign on the basis of the presence and distribution of the nucleolar fluorescence. In a group of 67 samples in which the nucleolar fluorescence was either readily observed or virtually absent, 47/48 (98%) of the malignant tumors were correctly identified. Of the bening lesions or normal breast specimens, 18/19 (95%) were correctly identified as negative for nucleolar fluorescence. These studies extend the results previously reported for a common nucleolar antigen in a broad range of human cancers to a larger series of malignancies of a particular organ. The tumor nucleolar antigen(s) were partially characterized by isoelectric focusing on 4% polyacrylamide gels. One major band had a pI of 6.3 and a minor band had a pI of 6.1. These antigens were not found in the normal human liver nucleoli.

Antigens, Neoplasm↗
PubMed1980

Initiation of transcription in permeabilized Novikoff hepatoma cells.

Novikoff hepatoma cells, grown in monolayer cultures, when permeabilized by treatment with lysolecithin, incorporated 3H-UTP at a high rate for 2 hours at 25 degrees. The incorporation was inhibited by initiation inhibitors such as rifampicin AF/013, heparin and aurintricarboxylic acid. About 75% of RNA polymerase II, and 45% of RNA polymerase I activities were inhibited by rifampicin AF/013. In contrast, transcription in isolated nuclei was not inhibited either by rifampicin AF/013 or heparin. The permeabilized cells apparently retain the mechanisms for reinitiation in vitro and may be a useful model for studies on the effects of proteins on gene transcription.

Animals↗
PubMed1980

Characterization of a nucleolar residue fraction that specifically transcribes preribosomal RNA.

Treatment of isolated nucleoli with Sarkosyl (2%) dissociated 99.5% of the proteins. The residual DNA-protein complex contained the endogenous transcriptional activity which had a high fidelity of RNA synthesis. Electron microscopic analysis of this residue fraction showed the presence of 150-200A diameter protein globules present along the length of some of the DNA fibers. SDS-polyacrylamide gel electrophoretic analysis of the proteins of the complex indicated that the subunits of purified RNA polymerase I were only a minor component of this complex. Associated with the complex were the U3 and 5S RNA.

Animals↗
PubMed1980

Reliability of the AMDP-system. A preliminary report on a multicentre exercise on the reliability of psychopathological assessment.

The AMDP-System is a documentation system for psychiatric data widely in use in the German-speaking countries. A summary of results of a multicentered study of interrater agreement of the Psychopathology Scale is presented. A new index of rater agreement was tested and the notion is discussed that the judgement of the presence and the absence of a symptom are two different processes with different reliability.

Germany, West↗
PubMed1980

Identification and partial purification of human tumor nucleolar antigen 54/6.3.

The present study was designed to characterize the human tumor nucleolar antigens found first in the HeLa cells and subsequently in a broad range of human cancers. For visualization of the antigens, HeLa cell nucleolar or nuclear protein fractions were analyzed on 4% polyacrylamide isoelectric focusing gels. The gels were incubated with rabbit antisera to HeLa cell nucleoli and then with fluorescein- or peroxidase-conjugated goat anti-rabbit immunoglobulin G. With this technique, two major nucleolar antigens (focusing at pH 6.3 and pH 6.1) were identified. These antigens were also found in the Namalwa cell, but not in human liver cells. Purification of the antigen(s) was achieved by selective extraction of Namalwa cell nuclei with 10 mM Tris-HCl (pH 8), 40 to 100% ammonium sulfate precipitation, diethylaminoethyl cellulose chromatography in which the antigen was eluted with 0.15 M NaCl buffer (DE-0.15M fraction), and use of isoelectric focusing gels. The immunostained bands (HuAg 6.3 and HuAg 6.1) and the bright nucleolar immunofluorescence of the HeLa cells were not observed after the antisera were preabsorbed with the DE-0.15M fraction. The immunostained bands (HuAg 6.3 and HuAg 6.1) and the nucleolar immunofluorescence of the HeLa cells were also observed when isoelectric focusing gels were incubated with antiserum from rabbits immunized with the DE-0.15M fraction. On the sodium dodecyl sulfate second dimension of the two-dimensional polyacrylamide gel electrophoresis, the antigen(s) migrated as single spots with appraent molecular weights of 54,000.

Antigens, Neoplasm↗
PubMed1980

Purification and characterization of cytosol protein 45/7.8 present in rapidly growing hepatomas.

Protein 45/7.8 (molecular weight X 10(-3)/isoelectric point) was found in the cytosol of several rapidly growing hepatomas including Morris hepatomas 3924A and 9618A2 and Novikoff hepatoma. It was not found in Morris hepatomas 7794A and 8999, which have intermediate growth rates, or in the slow-growing Morris hepatoma 9618A, normal rat liver, 18-hr regenerating rat liver, or livers of fetal rats. Protein 45/7.8 was isolated under nondenaturing conditions from Morris hepatomas 3924A and 9618A2 and Novikoff hepatoma in high purity by purification in three steps: ammonium sulfate fractionation; diethylaminoethyl cellulose chromatography; and hydroxylapatite chromatography. The protein was highly purified as shown by two-dimensional, isoelectric-focusing sodium dodecyl sulfate:polyacrylamide gels. The amino acid composition of protein 45/7.8 from the three tumors studied was very similar; the acid of protein 45/7.8 was proline, and its COOH terminus amino acid was tyrosine. Protein 43/8.1 found in normal liver is different from hepatoma protein 45/7.8 by amino terminus, amino acid composition, and tryptic peptides.

Amino Acid Sequence↗
PubMed1980

Two-dimensional gel electrophoresis of nuclear phosphoproteins of Novikoff hepatoma and regenerating liver.

Two-dimensional polyacrylamide gel electrophoresis patterns of 32P-labeled nuclear proteins in Novikoff hepatoma and regenerating liver relatively small number of the many nuclear protein spots were phosphorylated. The major phosphoprotein spots differed in size and shape from the stained protein spots. Seven phosphoproteins, 125/5.8, 125/7.2, 100/5.9, 85/5.9, 56/5.1, and 50/5.1 (mol. wt. x 10-(3)/pI in the Novikoff hepatoma nuclei were not found in the 18-h regenerating liver nuclei. One nuclear phosphoprotein, 54/6.5, was found in the liver but not in the hepatoma. The four major phosphoproteins, 45/5.3-6.0, 40/5.3-6.0, 35/5.3-6.0, and 25/5.8-6.8 containing about 60% of the total 32Pi of the nuclear proteins, were found in both types of cells. These proteins were of unusual density and shape. Some proteins, such as 125/5.8 and 85/5.9, were enriched in 0.01 M tris extract of the tumor, and proteins 125/7.2 and 56/6.1 were enriched in 0.35 M NaCl extract of the tumor.

Animals↗
PubMed1979

Comparison of nucleotide sequences of large T1 ribonuclease fragments of 18S ribosomal RNA of rat and chicken.

Nucleotide sequences of large T1 ribonuclease fragments of 18S ribosomal RNA of Novikoff rat ascites hepatoma cells and chicken lymphoblastoid cells were determined and compared. Among the 19 large T1 ribonuclease fragments examined of rat 18S ribosomal RNA, 12 fragments were found to be the same in chicken 18S ribosomal RNA. Three fragments of rat 18S ribosomal RNA were not found among large T1 ribonuclease fragments of chicken 18S ribosomal RNA. Four fragments of rat 18S ribosomal RNA were found to be changed in chicken 18S ribosomal RNA. All the changes were point mutations except the change in the largest T1 ribonuclease fragment 1 which is 21 nucleotides long. 2'-0-methylation at the center of the fragment was lost in chicken 18S ribosomal RNA; all the other nucleotides were the same.

Animals↗
PubMed1979

Nucleotide sequence of nucleolar U3B RNA.

U3A, U3B, and U3C are three distinct molecular weight nucleolar RNAs present in Novikoff hepatoma ascites cells. The primary nucleotide sequence of U3B, the most prominent of these U3 species, was determined. Purified U3B RNA was subjected to various enzymatic digestion procedures, including digests of 32P-labeled U3B RNA, RNA ligase, and polynucleotide kinase labeling, for determination of its primary sequence which is: (formula: see text). The 5'-terminus of the RNA has a "cap" and localized purine-rich regions were found near the 3'-terminus, which have been incorporated into a hydrogen-bonded region in a proposed secondary structure of the molecule.

Animals↗
PubMed1979

Studies on the specificity of preribosomal RNA transcription in nucleoli after selective deproteinization.

Fidelity of preribosomal RNA transcription in vitro was studied after selective deproteinization of nucleoli using either sequential salt extraction or sodium deoxycholate treatment. Homochromatography fingerprinting and identification of marker oligonucleotides from a T1 ribonuclease digest of the transcripts were used to evaluate the RNA products. These studies indicated that: (1) nucleoli retained their endogenous RNA polymerase I activity and the specificity of transcription up to 0.6 M NaCl extraction; (2) exogenous RNA polymerase I transcribed nucleolar chromatin only after 1.0 M NaCl extraction and the transcription pattern, like that of totally deproteinized DNA, was completely random; (3) extraction of nucleoli with deoxycholate resulted in a DNP complex in which the endogenous RNA polymerase I transcribed pre-rRNA specifically; however, it also initiated random transcription, producing a "mixed" fingerprint pattern on the homochromatogram. The random transcription was selectively inhibited either by deoxycholate or rifampicin AF/013. These studies indicate that the selectivity of pre-rRNA transcription is due both to the endogenous RNA polymerase I molecules that were involved in transcription in vivo and are tightly bound to the template and to factors in intact nucleoli which prevent random transcription by the released RNA polymerase I molecules.

Animals↗
PubMed1979

Isolation of a 70 000 molecular weight antigen of the Novikoff hepatoma.

Previous reports from this laboratory have indicated that a number of cytosol and nuclear proteins of Novikoff hepatoma cells were immunologically related [Yeoman, L. C., Jordan, J. J., Busch, R. K., Taylor, C. W., Savage, H., & Busch, H. (1976) Proc. Natl. Acad. Sci. U.S.A. 73, 3258; Busch, R. K., & Busch, H. (1977) Tumori 63, 347]. In preparation for analysis of their structure and function, studies were undertaken to purify nuclear antigen 2 from the cytosol of Novikoff hepatoma cells in high yield and purity. It was shown on Ouchterlony gels that cytosol nuclear antigen 2 formed a single immunoprecipitin band of identity with one of the bands extracted from Novikoff nuclear chromatin. In this study, a 70 000 molecular weight antigen was isolated from the cytosol of Novikoff hepatoma cells by ammonium sulfate fractionation, ion-exchange chromatography, and isoelectric focusing in a granulated gel bed. This protein which focused at a pI of 6.3 was labeled with 125I-labeled Bolton-Hunter reagent and purified on an Ultrogel AcA-44 column. As shown by electrophoresis on NaDodSO4-polyacrylamide gels, the antigen in the excluded volume migrated as a single protein with a molecular weight of 70 000. The overall purification over the starting material was 2890-fold.

Animals↗