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Biomedical subjects

M Unger

Publications and source records attributed to M Unger.

At least 91 records · Page 5Linked to original sources

Control of differentiation of a mammary cell line by lipids.

A rat mammary cell line (LA7) undergoes spontaneous differentiation into domes due to production of specific inducers by the cells. Some of these inducers may be lipids, and we show that lipids regulate this differentiation as both inducers and inhibitors. One inhibitor is the tumor promoter tetradecanoyl-13 phorbol 12-acetate. The inducers are saturated fatty acids of two groups: butyric acid and acids with chain lengths from C13 to C16, especially myristic acid (C14). Other inducers are myristoyl and palmitoyl lysolecithins, myristic acid methyl ester, and two cationic detergents with a tetradecenyl chain. We propose that the lipids with a C14-C16 alkyl chain affect differentiation by recognition specific receptors through their alkyl chains and that the effects obtained depend on the head groups. These lipids may be physiological regulators in the mammary gland.

Animals↗

Differentiation of a rat mammary cell line in vitro.

We have studied the development of fusiform (probably related to myoepithelial) cells in Rama 25 cultures [Bennett, D. C. Peachey, L. A., Durbin, H. & Rudland, P. S. (1978) Cell 15, 283--298]; we show that they are generated from special differentiated structures (projections) that contain a rapidly differentiating cell type (F-precursor cells). Clonal sublines isolated from projections develop in several directions under both environmental and genetic control. Some types of differentiation are reversible; others are irreversible. The various cell occurring in vitro may correspond to specific cell types in vivo.

Animals↗

Role of Thy-1 antigen in the in vitro differentiation of a rat mammary cell line.

A line of rat mammary cells, LA7, undergoes differentiation into domes or ridges or projections under partial medium control. Immunofluorescent studies show that at the time of dome formation the LA7 cultures express the Thy-1 antigen at the borders between cells. Exposure of the cultures to certain monoclonal anti-Thy-1.1 sera prevents formation of new domes and causes disappearance of preexisting ones; antisera to whole cells produce no visible effect. Cultures exposed to anti-Thy-1 sera at effective concentrations of antibody against domes show morphological changes and ridge formation. It seems that the specific interactions of these antisera with the Thy-1 antigen redirects the differentiation program of the cells.

Animals↗

Thy-1: a differentiation marker of potential mammary myoepithelial cells in vitro.

The rat mammary cell line Rama 25 [Bennett, D.C., Peachey, L.A., Durbin, H. & Rudland, P.S. (1978) Cell 15, 283--298] differentiates morphologically in vitro from a cuboidal form to a fusiform cell resembling myoepithelial cells. This differentiation occurs in all clonal isolates of the line. By using three different rabbit antisera specific for Thy-1, we have found that antigenic differentiation accompanies morphologic change to the fusiform state. Very few cuboidal cells had Thy-1 detectable on their surfaces in the living state; but after acetone fixation cytoplasmic Thy-1 was detected by immunofluorescence in all cells of the cuboidal type. Thy-1 specificity was established by the fact that immunofluorescence induced by rabbit anti-rat thymocyte serum was abolished by absorption with rat brain but not with erythrocytes, kidney, or liver; immunofluorescence induced by rabbit antiserum to purified Thy-1 glycoproteins from mouse lymphomas was absorbed by Thy-1 positive mouse and rat lymphomas. Surface Thy-1 provides a potentially valuable antigenic marker in the Rama 25 line for studying the differentiation of mammary myoepithelial cells.

Animals↗

[Histological changes in the placenta following tokolysis therapy (author's transl)].

In 138 tokolytically treated cases of imminent abortion or premature birth the secundines were examined histologically and compared with 390 cases of pathological gravidities or births without tokolysis therapy. The frequency of occurrence of morphologically manifested circulatory disturbances following tokolysis therapy was equal to that in the untreated cases, the rate of ascendent infections was only slightly increased. In tokolytically treated placentas with the histological pattern of "dissociated disturbed maturation" and "Maturitias retarda" are prevailing. Thus in most cases sufficient supply of the fetus is possible and the critical phase of uteroplacental insufficiency with the danger of abortion or premature birth may be overcome. There were no hints at direct influences of tokolysis on placental morphology.

Abortion, Threatened↗

[Endooesophageal prostheses and their complications (author's transl)].

After inserting an oesophageal prosthesis complications could be demonstrated in 53 cases (65%) from a total of 81 autopsies. Age distribution, tumour localisation and its relation to the development of local complications are analysed. Notwithstanding the high incidence of complications endoprostheses should be given preference to gastric fistulae.

Adult↗

Cutting fluids and their effects on the skin of mice. An experimental study with special reference to carcinogenicity.

Reports of skin malignancies due to occupational exposure have decreased since the introduction of solvent-refining of mineral oil fraction in the manufacture of oil based cutting fluids. Commercial mineral oil based cutting fluids caused local and general pathological changes after repeated application to the skin of mice in the present study. Forty-eight per cent of the mice exposed to oils showed severe dysplasia or malignancy of the skin on histological examination. The corresponding figure for the control group, where various additives were used was 8 per cent. The frequency of papillomas was also increased in the mice exposed to oils. The systemic lesions included focal necrosis of the liver, associated with amyloid deposition, as well as amyloidosis of the skin, spleen and kidneys. The substances responsible for these apparent carcinogenic properties of the complex mixtures may be polycyclic hydrocarbons; the latter are still present in the commercial products despite solvent refining; on the other hand the carcinogens may be additives to the cutting oils the composition of which is generally a trade secret.

Amyloidosis↗

Potentiation of pulmonary vasoconstrictor response with repeated intermittent hypoxia.

To determine the consistency of the pulmonary vasoconstrictor response to hypoxia, dogs were anesthetized, intubated, and ventilated alternately with air and 10% oxygen. Catheters were placed in the pulmonary artery for measurement of pulmonary artery pressure (PAP), pulmonary capillary wedge pressure, and cardiac output and in the femoral artery for monitoring systemic blood pressure and arterial blood gases. Arterial PCO2 and pH were kept at steady levels throughout by ventilating the dogs with a respirator so that only the isolated effect of hypoxia on the pulmonary vasculature was studied. It was found that there was a progressive rise in the PAP with repeated exposure to the same hypoxic stimulus. In 12 dogs, the mean increase in the PAP was 28% above the base line on the 1st hypoxic exposure, rising to 99% by the 10th exposure over the course of 5 h. It was concluded that interpretation of action of agents blocking or enhancing the hypoxic response must take into account this inherent potentiation of the response on repeated exposure to hypoxia.

Animals↗

[Isolated thrombotic omphalovasculitis with marginal insertion--a rare umbilical cord complication].

Report about 2 cases of a rare umbilical cord complication, the isolated omphalovasculitis thrombotica with marginal insertion and about their effects at the feto-placentare unity. Reference is given to an eventual embolic cause of praenatal thrombosis. It will be recommended a regular histological examination of the marginal respectively velamentous insertion for clarification of unclearly fetal deaths.

Adult↗

[Methods of localization of chorioamnionitis and their clinical value].

121 out of 390 placentas of mostly pathological deliveries and preganancies were cases of chorioamnionitis. Histological studies have been performed under topographical respects. Several localisations (dynamic phases) of ascending infection of the secundinae are being described and their clinical relevance is being assessed. 1)"Nomal secundinae" or "physiological leucocytosis at ruptured chorionic membranes": there are but a few cases (3 to 5%) of amniotic infection syndroms or morphological signs of an aspiration of infected amniotic fluid and fetal sepsis. 2) "Isolated leucocytosis of the vessels of the umbilical cord and the chorionic plate": it is mostly caused by a fetal hypoxia; relatively seldom it is the result of an infection (about 10%). 3) "Partial phlegmon of the secundinae" (phlegmon of the chorionic membrane with spreading to the periphery of the chorionic plate): about 30% amniotic infection syndrom or infected amniotic fluid (and fetal sepsis respectively. 4) "Subtotal phlegmon of the secundinae" (phlegmon of the chorionic membrane and the chorionic plate in part, spreading to the umbilical cord): about 50% amniotic infection syndrom or infected amniotic fluid (and fetal sepsis) respectively. 5) "Total phlegmon of the secundinae" : in the majority of cases (about 65%) signs of infection damage on mother and/or fetus are visible.

Amnion↗

Development of an efficient system for the separation of indole alkaloids by high performance liquid chromatography and its applications.

An efficient system for the analysis of indole alkaloids by HPLC on a reversed-phase column using an ion pair technique is described. The optimised chromatographic conditions allowed the successful separation of 22 standard monoterpenoid indole alkaloids (including some isomers) and tryptamine. The described HPLC system was applied to the analysis of alkaloids in intergeneric somatic hybrid cell cultures of Rauvolfia serpentina x Rhazya stricta.

Cells, Cultured↗

The stomach and pulmonary interlobular space as unusual sites of osteosarcoma.

The authors report a girl with high-grade intraosseous osteosarcoma of the left femur who lost one eye during early infancy for an unknown reason. Nine months after treatment, osteosarcoma in the stomach was detected and completely excised when the girl underwent endoscopy for Helicobacter pylori infection. Three years later osteosarcoma in the pulmonary interlobular space was noticed and completely removed. The girl is doing well and free of disease 26 months after the last resection.

Child↗

The financial status of Catholic hospitals: 1982-1983.

Recently available figures for 1982 and 1983 show that Catholic hospitals as a whole attained positive ratios of net income to fund balances and that these gains exceeded inflation in both years. The financial picture varies, however, when data for specific categories of Catholic hospitals are examined. For example, smaller hospitals relied more on borrowed funds to finance assets and generate profits, and for many of them these profits still did not exceed the 1983 inflation rate. Hospitals particularly vulnerable to diagnosis-related group payment--that is, teaching hospitals, hospitals with negative operating income, and hospitals adding beds--possessed less liquidity than Catholic hospitals aggregately. Hospitals in each of these categories experienced less-than-average basic profitability as well.

Catholicism↗