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Biomedical subjects

J Song

Publications and source records attributed to J Song.

At least 397 records · Page 22Linked to original sources
PubMed1987

Postnatal evolution of the human pineal gland. An immunohistochemical study.

Pineal glands from 16 infants ranging from 38 weeks gestation to 3 years of age were fixed in buffered formalin; Paraffin sections were stained for neuron-specific enolase, glial fibrillary acidic protein, and S-100 protein (S-100) using the peroxidase-antiperoxidase method and hematoxylin and eosin, Masson-Fontana, and Bodian stains. The pineal glands of neonates consisted of cords of closely packed, dark, nucleated cells (type I) with intervening loosely arranged, large, clear cells (type II). The type I cells were frequently pigmented and occasionally exhibited rosette formation. They were positive for S-100 and negative for neuron-specific enolase. The type II cells were strongly positive for neuron-specific enolase and negative for melanin and S-100. The type I cells were the predominant cell type at birth; however, the number of type II cells gradually increased with age, and by the age of 1 year, only scattered S-100 positive cells, consistent with sustentacular cells, were found. The findings indicated that the human pineal glands undergo a remarkable morphologic and functional evolution as an endocrine organ in the postnatal life.

Cell Differentiation↗
PubMed1986

Characterization of a new monoclonal antibody to a cell surface antigen on colorectal cancer and fetal gut tissues.

Murine hybridoma were raised against the human colon carcinoma cell line CL-187. One clone was found to secrete a monoclonal antibody (ND-1) that recognizes a large external antigen (LEA) on human colon carcinoma cells. With indirect immunofluorescence on formaldehyde-fixed cells, more than 90% of the human colorectal carcinoma cell lines tested expressed LEA. Almost all of the 46 human noncolorectal and nonhuman cell lines tested did not express LEA, including cancer cell lines from other endodermally derived tissues. Staining of frozen sections from human colorectal tumors, noncolorectal tumors, normal adult, and normal fetal tissues showed expression of the antigen on colorectal cancer tissue, fetal colon, and fetal biliary epithelium. LEA can also be detected in the serum and ascites of colorectal cancer patients. Double indirect immunofluorescence with rabbit anti-carcinoembryonic antigen (CEA) antibody and ND-1 monoclonal antibody on a human colorectal carcinoma cell line showed that LEA is distinct from CEA. Physicochemical analysis of LEA showed that it has a large molecular weight, is resistant to extraction from the cell surface, and that sialic acid is an important component of the antigenic site. Because of the specificity for colorectal cancer tissue along with certain biochemical properties, LEA appears to be unique when compared with other tumor-associated antigens. Further research is needed to define the clinical usefulness of LEA in either the diagnosis or treatment of colorectal carcinoma.

Animals↗
PubMed1985

Effect of aging on human aortic protein composition. I. One-dimensional polyacrylamide gel electrophoretic analysis of tissue extracts.

Proteins extracted from matching areas of homogenized intimas of 17 human aortas, from two age groups (15-34 and 35-82), were studied after separation by polyacrylamide gel electrophoresis, silver staining, and densitometric scanning. Several definite protein bands including 6 major and 16 minor bands were identified in 17 aortic intima samples grossly and microscopically lesion free. However, such electrophoretic patterns were found to differ in the two age groups studied. For instance, (1) the integrated densities (amounts) of protein bands 1, 6, 13, 16, and 19 which we interpreted as of mural vascular origin were significantly higher in the younger age group, whereas the amounts of bands 2, 7, 9, 11, and 21 suspected to be of plasma origin were found to be significantly higher in the older age group; (2) protein band No. 8 was found to be double in the younger age group vs a single line in the older age group, whereas band No. 12 was the opposite. These changes in protein composition appear to correlate closely with diffuse intimal thickening found histologically in older age group, and will be further studied to relate to those in atherosclerotic lesions.

Adolescent↗
PubMed1985

Effect of aging on human aortic protein composition. II. Two-dimensional polyacrylamide gel electrophoretic analysis.

Arterial intima proteins were extracted by 9 M urea from matching histologically atheroma-free areas of 27 human thoracic aortas of both sexes from younger (15-34) and older (35-82) age groups and studied after separation by high-resolution two-dimensional polyacrylamide gel electrophoresis. Seventeen specific protein groups on each gel were identified according to their relative charges and molecular weights and their distribution in the two age groups compared. Some plasma-derived proteins occurred rarely in young aortas while they were consistently found in those from older cases, i.e., protein group 4 (alpha 1-antichymotrypsin) 1/13 (8%) vs 12/14 (86%), group 7 (haptoglobin beta-chain) 1/13 (8%) vs 13/14 (93%) and groups 6 and 9 (IgG chains) 3/13 (23%) vs 9/14 (64%), respectively. Other plasma-derived proteins such as group 3 (albumin) and 5 (alpha 1-antitrypsin) were identified in all samples of both age groups but their expression in the aortic intima increased with age. Proteins which are typically found intracellularly such as those from groups 11 (actin), 12 (cytoskeleton proteins), and 13 (tropomyosin-like proteins) appeared in samples of intima of both age groups but were less apparent in older specimens. These studies suggest that the changes in aortic intima protein distribution in the absence of atherosclerosis closely correlate with histological changes such as intimal thickening often found with aging, providing new sensitive markers of vascular senescence.

Adolescent↗
PubMed1984

Localization of endoplasmic reticulum in living and glutaraldehyde-fixed cells with fluorescent dyes.

Certain fluorescent dyes, previously reported to localize mitochondria, when used at higher concentrations also localize a continuous net-like structure in both living and glutaraldehyde-fixed cells. A similar reticular structure can be detected by phase-contrast microscopy and whole-mount electron microscopy in potassium permanganate-fixed cells as well. This structure is mostly tubular, with some patch-like areas, and is likely to be the endoplasmic reticulum (ER). The organization of the reticular structure is sensitive to colchicine and rotenone but not to cytochalasin B, taxol, monensin, the calcium ionophore A23187, 12-O-tetradecanoylphorbol 13-acetate, or hydrocortisone.

Animals↗
PubMed1981

Theory on prospect of population evolution processes.

This paper is aimed at investigating the dynamic process of population growth applied to population of the People's Republic of China. The discrete and continuous models of population evolution process are revised and adjusted to suit the social conditions of China. The relationship between two kinds of models is established. A series of new formulae of demographic indices are studied and defined as functions on the negative space of generalized solutions of the population equation. Based on survey data collected in China for recent years, the prospect of population growth according to different projections is offered for a one-hundred-year period from now on.

Demography↗