PubMed Health⌕ Search

Biomedical subjects

H C Wang

Publications and source records attributed to H C Wang.

At least 163 records · Page 9Linked to original sources
PubMed1985

Characterisation of a new cell line (CJ18) from a patient with 'hairy' cell leukaemia.

A cell line (CJ18) has been established from the peripheral blood of a patient with hairy cell leukaemia (HCL) in a leukaemic phase. They grow slowly in large clumps with a doubling time of 3-4 d. 8% show positivity for surface immunoglobulin G and a small percentage (5%) are positive for intracytoplasmic immunoglobulin. They are B1,Ia1 positive and CALL, TdT and OKM1 negative. Although they are Epstein Barr Virus Nuclear Antigen (EBNA) positive they have several features not found in other EBNA positive B lymphoblastoid cell lines which suggest they may be derived from the patient's leukaemic hairy cells. They are strongly positive for tartrate resistant acid phosphatase, esterase positive, contain numerous lysosomes and are able to phagocytose sheep red blood cells after exposure to tetradecanoyl-12, 13-phorbol acetate (TPA). Following exposure to retinoic acid and TPA they adhere to plastic with numerous slender processes, a feature seen in HCL cells.

Antibodies, Monoclonal↗
PubMed1984

Increased metastatic ability and bone formation of a mammary adenocarcinoma in vivo after in vitro passaging.

On in vitro passaging of the rat mammary adenocarcinoma R3230AC cell line, phenotypic changes occurred that were expressed in vivo. The histology of this mammary adenocarcinoma changed to a fibrosarcoma and then to an osteosarcoma. The overall population of early passaged cells consisted of a mixture of predominantly epithelial-like cells and few fibroblast-like cells; however, later passaged cells consisted more of the latter type. Along with the changes in histology, the tumor line also became highly metastatic in animals after in vitro passaging. The etiology of these phenotypic changes was not determined. Cytogenetic studies revealed chromosome changes in cells of later passages. Cells of 90 or greater passages that produced bone tumors were found to have fewer chromosomes and a metacentric marker isochromosome. In this report a correlation is made between the aberrant change in histology, increased metastatic ability and the presence of a marker chromosome of the R3230AC tumor.

Adenocarcinoma↗
PubMed1984

Seroimmunity to poliomyelitis in hospital personnel.

Neutralizing antibody titers to poliovirus type 1, 2 and 3 were examined in paired serum specimens obtained from 43 female hospital personnel and laboratory workers at Veterans General Hospital. Before vaccination, 23.2% of those studied did not have neutralizing antibodies to one or more types of poliovirus, and 4.6%, 13.9% and 7.0% lacked serum neutralizing antibodies to poliovirus type 1, 2 and 3, respectively. In a comparison of the serological responses evoked by oral poliovirus vaccine in the same persons, a striking difference in antibodies was shown in the geometric mean titers and no lack of antibodies was found after oral poliovaccine immunization. Therefore immunization with oral poliovirus vaccine should be considered in the future as to improved protection for such high risk people.

Adult↗
PubMed1983

The use of cell fusion to analyse factors involved in tumour cell metastasis.

Cell fusion has been used to study some of the factors involved in the process of metastasis. Highly metastatic rat mammary adenocarcinoma cells were fused with various non-metastatic cells and the hybrid clones isolated. These were then tested for their metastatic potential either by injecting the cells intravenously and measuring lung colony formation or by injecting the cells subcutaneously and measuring their ability to form lymphatic metastases. With most hybrid clones tested, the metastatic potential was either inhibited or greatly suppressed; thus this phenotype is a recessive characteristic. We also monitored the hybrid cells' ability to produce plasminogen activator (PA) a serine proteinase thought to be involved in the formation of metastatic lung foci. Whilst the highly metastatic parent cells produced large quantities of PA, none could be detected in the non-metastatic lines. Although the hybrid clones produced little PA activity this could not be correlated with their decreased metastatic potential in that one clone, after extensive in vitro culture, reverted to a more metastatic line without a concomitant increase in PA activity. The suppressed PA activity may be due to the presence of an inhibitor that is spontaneously produced by the hybrid cells.

Adenocarcinoma↗
PubMed1983

Familial supernumerary microchromosome mosaicism: phenotypic effects and an attempt at characterization.

A healthy normally intelligent man and his two daughters who had mild developmental delay and different malformations were determined to have an acrocentric supernumerary microchromosome (MC). The father and both daughters were noted to be mosaic for the MC, perhaps suggesting mitotic instability of the MC cell line with loss over time. The MC was negative staining on G-banding and showed absence of centromeric heterochromatin on C-banding. A centromere was identified with silver staining; no NORs were identified. The MC approximated the size of the short arm of the Y chromosome and showed cytologic behavior similar to that of a Y chromosome. H-Y antigen and Y-DNA gene probe studies failed to confirm a Yp origin.

Abnormalities, Multiple↗
PubMed1983

Repression of cointegration ability of insertion element IS1 by transcriptional readthrough from flanking regions.

We describe a repression mechanism in which read-through messages transcribed from a gene into an IS1 sequence inhibit its ability to mediate plasmid cointegration. This mechanism was derived from the demonstration that removal of the promoter region of the chloramphenicol resistance gene in transposon Tn9, or introduction of a strong transcription terminator of phage T7 downstream of the chloramphenicol resistance gene, increases the cointegration ability of the downstream IS1 sequence when in a particular orientation. The cointegration ability of an IS1 sequence downstream of the chloramphenicol resistance gene but in an orientation opposite that of the above-mentioned IS1 sequence also can be repressed. Analysis of transcripts synthesized in vitro showed that the transcripts of the chloramphenicol resistance gene were read through into the IS1 sequence located downstream of the gene in either orientation. Repression of this type may be one mechanism that controls the rate of transposition of the IS1 element, which apparently does not encode a structural gene for repressor.

Chloramphenicol↗
PubMed1981

Demonstration of axial elements of sex vesicles of spermatocytes using Coomassie brilliant blue.

The axial element of sex chromosomes in the sex vesicle of rat and mouse spermatocytes has been visualized under the light microscope by the dye Coomassie brilliant blue (CBB). After staining in the CBB solution for 3-10 minutes, the axial elements appeared as darkly stained threads in the sex vesicles, whereas in controls stained with Giemsa or carbol fuchsin, the sex vesicles were usually uniformly stained. The axial elements are best seen when chromosome preparations were made by the flame drying technique. In rat spermatocytes the staining quality could be further improved by a brief treatment with trypsin solution (0.025%). The CBB staining procedure is simple and easily controllable. The results suggest that the CBB stained material is protein in nature and is more resistant to trypsin digestion than other nuclear proteins.

Animals↗
PubMed1979

Nucleolar organizer regions (NORs) in Chinese hamster chromosomes as visualized by Coomasie brilliant blue.

Nucleolar organizer regions (NORs) of Chinese hamster chromosomes have been demonstrated by using a Coomasie brilliant blue dye (CBB) method. The staining procedure involved is simple and the results are reproducible. The staining process is easily controllable because over-staining of the chromosomes seldom occurs. The CBB solution is stable (pH 3) and can be used for many days at room temperature. Contrary to the silver technique, the stained material in the NORs is resistant to acid extraction. Since it is sensitive to trypsin treatment, it is suggested that the CBB stained material is protein in nature.

Animals↗