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Biomedical subjects

J Gaub

Publications and source records attributed to J Gaub.

47 records · Page 3Linked to original sources
PubMed1981

Cytophotometry of liver cells from ethanol-fed rats: ethanol causes increased polyploidization and protein accumulation.

Cellular protein and DNA content were determined by Feulgen--Naphthol Yellow S cytophotometry on isolated liver cells from rats fed ethanol for 2--6 months. It was found that parenchymal liver cells after ethanol feeding contained 13% more protein than cells of the same ploidy class from controls; that the average parenchymal cell in ethanol-fed rats contained 16% more protein than in controls due to the increased occurrence of polyploid cells; that the protein accumulation develops over 2 months, does not progress thereafter and disappears after a few days of reduced ethanol intake; that the tendency to form polyploid cells is accentuated during liver regeneration. It is suggested that the effect of alcohol on microtubular function, which is regarded as the cause of the protein accumulation, may also bring about increased polyploidization.

Animals↗
PubMed1980

Evidence for liver cell proliferation during fatal acute liver failure.

Liver cell regeneration was assessed by determining the mitotic index and the frequency of liver cells with interploid DNA values in livers from patients dying from fulminant hepatitis. For comparison, the same parameters were determined in patients with uncomplicated hepatitis. We found comparable levels of regeneration in the two groups, indicating that the rate of liver cell destruction is a major determinant in the prognosis of acute liver failure. Accordingly, measures to prevent liver cell necrosis seem at least as important as stimulation of regeneration. Judged from available experimental evidence, substances with documented hepatotrophic effect in animals, such as insulin and glucagon, may therefore not be effective in acute liver failure unless the patient has impaired secretion of these substances.

Adult↗
PubMed1977

Nuclear non-histone protein content of G0/G1 cells as related to growth fraction in mouse mammary tumors.

In eight mouse mammary tumors with varying growth fractions DNA and non-histone nuclear protein (NHNP) were determined by absorption cytophotometry of Feulgen-Naphthol Yellow S stained, isolated cells. It was found that: 1. The mean NHNP content of cells with postmitotic DNA content (G0 + G1) increased with increasing growth fraction. 2. The mean NHNP content of S and G2 cells in the eight tumors did not vary significantly with growth fraction. 3. The frequency distributions of NHNP in G0/G1 cells were unimodal and right-skewed. The results are interpreted as follows: A) G0 cells differ from G1 cells by their lower content of NHNP. B). If it is assumed that the G0 and G1 compartments are arranged in series, the cells in the transition from G0 to late G1 may account for the unimodality and skewedness of the NHNP frequency distributions of postmitotic cells.

Animals↗
PubMed1976

Feulgen-Naphthol Yellow S cytophotometry of liver cells. The effect of formaldehyde induced shrinkage on nuclear Naphthol Yellow S binding.

1. In isolated liver cells, fixed in 4 per cent formaldehyde (NFS) for Feulgen-Naphthol Yellow S (F-NYS) staining of DNA and protein, nuclear shrinkage increases the nuclear concentration of solids to 46 per cent (w/v) before the start of the NYS staining. 2. When a fixative mixture of methanol:acetic acid:formalin (85:5:10 by volume; MAF) is used, the concentration of nuclear solids during NYS staining remain at a physiological level of 19 per cent. 3. By exposing liver cells to NFS for 10 to 120 seconds before fixation in MAF, increasing nuclear shrinkage can be induced with increasing pretreatment in NFS. Nuclear NYS binding decreases in parallel with the decreasing nuclear volume in cells thus treated. As the shrinkage induced reduction in NYS binding may vary with the net charge of nuclear non-histone proteins, MAF fixation must be preferred for quantitative determinations of nuclear non-histone protein in F-NYS stained, isolated cells. 4. Fixation in MAF offers the same advantages as NFS fixation as regards the small loss of proteins during the Feulgen staining procedure and the excellent reproducibility of the F-NYS staining. Storage of MAF fixed cells in the fixative for a few days does not alter their F-NYS staining properties. 5. In MAF fixed, F-NYS stained cells there is no NYS binding to histone basic amino acid residues.

Acetates↗
PubMed1976

Diurnal variations in endogenous RNA polymerase activity and amounts of nuclear non-histone protein, DNA and cytoplasmic protein in rat liver.

From rats fed ad libitum and kept under a 12 + 12 h light/dark regimen, the DNA dependent RNA polymerase activity of liver cell nuclei was determined avery four hours. From identical rats, nuclear non-histone protein and DNA, and cytoplasmic protein was determined by Feulgen-Naphthol Yellow S cytophotometry of isolated liver cells. The minimum: maximum ratio of the RNA polymerase activity is 0.77; the min:max ratio of nuclear non-histone protein is 0.84. These two parameters have identical time courses with a gradual decline during the light period and a sharp rise after the onset of the dark period. The variations in nuclear DNA content, estimated as the amount of Feulgen stain bound, closely parallel those of the RNA polymerase activity and nuclear non-histone protein content (min:max = 0.96). The amount of cytoplasmic protein per cell also varies throughout the day, but its time curve lags behind those of nuclear non-histone content and RNA polymerase activity. These results are consistent with the concept of nuclear non-histone proteins as de-repressors of the DNA template in differentiated, non-proliferating cells, and support the validity of using Feulgen-Naphthol Yellow S cytophotometry of nuclear non-histone proteins as an estimate of gene expression in such cells.

Animals↗
PubMedDate not supplied

Rat liver regeneration after 90% partial hepatectomy.

In previous studies, 90% partial hepatectomy in the rat was invariably accompanied by 100% mortality within 40 hr. This paper describes a technique by which 90% of the liver mass can be removed with only 14% mortality, provided that rats have free access to glucose-containing drinking water. Measurements of total liver DNA, [3H]thymidine labeling index and mitotic index suggest rapid cell proliferation, commensurate with a powerful regenerative stimulus. In the presence of normoglycemia, peripheral insulin and glucagon concentrations were elevated to levels normally observed in the portal vein.

Animals↗
PubMedDate not supplied

Computed tomography of the lungs in acquired immunodeficiency syndrome. An early indicator of interstitial pneumonia.

Computed tomography of the chest was performed on 42 occasions as part of the diagnostic work-up in 26 homosexual men with, or suspected of the acquired immunodeficiency syndrome (AIDS). In 17 cases both the chest radiographs and the lung scans were abnormal, and bronchoscopy and/or lung biopsy established an etiologic diagnosis in the majority of these cases. In 9 cases CT of the lungs revealed unequivocal interstitial infiltration in the presence of a normal chest radiograph, and subsequently an etiologic agent was demonstrated in all these cases. In 9 cases, patients with symptoms indicative of pulmonary infection had both a normal chest radiograph and a normal lung scan, and in none of these cases did the clinical course or additional diagnostic procedures indicate the presence of current opportunistic lung infection. CT of the lungs seems to identify accurately those patients with severe HIV-related diseases in whom invasive diagnostic procedures such as bronchoalveolar lavage and/or lung biopsy should be done.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Cytophotometry of feulgen-naphtol yellow S stained liver cells--a computerized method for the calculation of nuclear protein.

A computerized method was developed to calculate the nuclear protein content of Feulgen-Naphtol Yellow S stained liver cells from cytophotometric data. After two consecutive scannings at 570 nm (DNA) and 435 nm (protein), the nuclear localization and shape are defined and nuclear protein is calculated by a method which corrects for the nuclear-cytoplasmic overlap at the nuclear periphery. The results obtained by the procedure are highly reproducible and are in accordance with the results of biochemical determinations of nuclear and total cell protein reported by others.

Animals↗