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M Unger

Publications and source records attributed to M Unger.

At least 37 records · Page 2Linked to original sources
PubMed1994

Vertical human immunodeficiency virus transmission: a study of placental pathology in relation to maternal risk factors.

We examined 48 placentas of human immunodeficiency virus (HIV)-exposed pregnancies morphologically for HIV-specific changes and immunohistologically for the presence of HIV antigen and RNA. Findings were correlated to infectious states of the children and maternal risk factors. Few HIV antigen-positive Hofbauer cells and HIV RNA positive syncytiotrophoblast and Hofbauer cells were detected. HIV-positive cells in the placenta did not correlate with intrauterine infection and maternal immunologic parameters. Light microscopically, we found two changes: immaturity of the terminal villi and allantois vasculopathy. These changes, however, are not HIV specific. Our results show that vertical HIV transmission cannot be diagnosed by morphological examination of the placenta.

Acquired Immunodeficiency Syndrome↗
PubMed1993

Toxicity of sediments and sediment pore waters from the Grand Calumet River-Indiana Harbor, Indiana area of concern.

The assessment of contaminated sediments is a difficult task due to the complex nature of the sediment matrix and the potential for exposure of aquatic organisms to in-place contaminants via several routes. Differential species sensitivity also precludes the completion of a meaningful environmental assessment with only one species. Therefore, a battery of assays approach with the Microtox assay, 48 hr Daphnia magna and Ceriodaphnia dubia tests and a 10-day Chironomous tentans test was used to evaluate the toxicity of sediment pore waters and whole sediments from the Grand Calumet River-Indiana Harbor, Indiana area of concern. All toxicity tests indicated that the test fractions (pore water, whole sediment) from each study site were toxic to the test species. A toxic units (TU) approach was used to compare measured TU from each assay with calculated TU based on chemical analyses of pore waters and whole sediments and the results of reference toxicant tests. Based on the results of these analyses, ammonia, polycyclic aromatic hydrocarbons, metals, petroleum hydrocarbons, and bicarbonate ion appear to be the major contaminants of environmental significance to benthic invertebrates within the study area.

Animals↗
PubMed1992

Prenatal diagnosis of monosomy 18 and ring chromosome 18 mosaicism.

The case of monosomy 18/ring chromosome 18 mosaicism which was detected prenatally by amniocentesis is presented. The pregnancy was terminated in week 18. Autopsy showed complex malformation of the fetus consisting of cebocephaly, hypotelorism, microphthalmia, severe defects of brain development, and arrest of placental maturation.

Adult↗
PubMed1992

Demonstration of HIV-1 infected cells in human placenta by in situ hybridisation and immunostaining.

AIMS: To show the presence of HIV infected cells in the placentas and membranes exposed to HIV during pregnancy, and to trace the possible transmission routes from mother to fetus. METHODS: Twenty three therapeutic abortions and 11 term placentas were investigated for the presence of HIV antigen by immunostaining with HIV core protein specific antibodies and HIV nucleic acids by in situ hydridisation (ISH) with a 35S-labelled HIV specific RNA probe. RESULTS: HIV antigen as well as HIV RNA positive cells were rarely found in placental tissue and membranes. In therapeutic abortions HIV antigen was shown in 10 out of 23 placentas, HIV RNA in two. HIV antigen was detected in five out of 11 term placentas and HIV RNA in two. Infected cell types comprised syncytiotrophoblasts, Hofbauer cells, amnionic epithelium, chorionic macrophages as well as maternal lymphocytes in the intervillous space and decidua. CONCLUSION: These data suggest that the transmission routes are: (1) a haematogenous route from the maternal intervillous space to villous stromal cells; (2) from chorion laeve to amnionic fluid and vice versa. Two additional transmission routes are partly suggested by the data: (1) in early gestation by direct extension from basal decidua to budding trophoblastic cells; (2) from the capsular decidua to chorion laeve and chorionic plate, entering the fetal circulation via the small veins.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Phase I and imaging trial of indium 111-labeled anti-epidermal growth factor receptor monoclonal antibody 225 in patients with squamous cell lung carcinoma.

Murine monoclonal antibody (MAb) 225 (IgG1) against the epidermal growth factor (EGF) receptor competitively blocks EGF binding and inhibits EGF-induced activation of receptor tyrosine kinase and cell proliferation. The effect of MAb 225 was studied in a phase I trial in patients with inoperable squamous cell carcinoma of the lung, which invariably expresses high levels of EGF receptors. Groups of three patients received total doses of MAb 225 ranging from 1 mg to 300 mg. Except at the lowest dose, each infusion included 4 mg of indium 111 (111In)-labeled MAb 225. No toxicity was observed. Tumors were imaged in all patients who received doses of 20 mg or greater. Presumed metastases greater than or equal to 1 cm in diameter were imaged with doses of 40 mg or greater. Single-photon-emission-computed tomography could be carried out at the 120-mg and 300-mg doses and significantly improved tumor visualization. All patients produced anti-murine antibodies. We conclude that treatment with an MAb that inhibits EGF receptor function is safe at the doses and schedule studied. 111In-labeled MAb images squamous cell lung carcinoma; tumor uptake of the labeled MAb is dose dependent. Further studies are warranted to explore the potential therapeutic efficacy of anti-EGF receptor MAbs and other agents that act in a comparable manner.

Adult↗
PubMed1991

Influence of noradrenergic input into the hypothalamic paraventricular nucleus on fever in the guinea-pig.

The febrile response of guinea-pigs to a bacterial pyrogen was tested under different experimental conditions: (1) during electrical stimulation of the hypothalamic paraventricular nucleus (PVN), (2) after destruction of noradrenergic afferents into the PVN by 6-hydroxydopamine (6-OHDA), (3) during a microinfusion of noradrenaline (NA) into the PVN. Electrical stimulation of the PVN neurons by implanted microelectrodes reduced the febrile response to 45% of the control values. This confirmed the proposed antipyretic function of these neurons. Chronic destruction of noradrenergic afferents to the PVN by microinjected 6-OHDA also resulted in a significant reduction of febrile responses to 38% of the control values. A microinfusion of NA into the PVN enhanced the febrile responses to bacterial endotoxin by 39% in comparison to animals microinfused with the solvent (0.9% NaCl). Immunoreactivity to an antiserum against arginine vasopressin (AVP) was compared in PVN neurons of 6-OHDA-treated and of control animals. The number of AVP-immunoreactive perikarya and the intensity of immunoreactivity were increased in the animals treated with 6-OHDA, especially in the medial part of the PVN. Since fever was increased by microinfused NA and decreased by 6-OHDA treatment, we assume an inhibitory influence of noradrenergic brain stem afferents on the proposed antipyretic vasopressinergic system of the PVN.

Afferent Pathways↗
PubMed1991

Osteosarcoma of the maxilla. Case report and ultrastructural study.

An osteosarcoma, occurring in the maxillary alveolar ridge of a 17-year-old girl is presented. The tumor consisted predominantly of pleomorphic, mainly osteoblast-like and anaplastic cells. At the ultrastructural level the osteoblast-like cells were characterised by excentrically situated lobed nuclei, extensively swollen, dilated and rough endoplasmic reticulum (RER), polymorphism of mitochondria and sparse Golgi-systems. The undifferentiated cells were characterized by large, electron-lucent nuclei and paucity of non-dilated RER and mitochondria. The intercellular matrix contained collagen fibers with areas of focal collections of calcification.

Actin Cytoskeleton↗
PubMed1991

Pulmonary function in men after oxygen breathing at 3.0 ATA for 3.5 h.

As a pulmonary component of Predictive Studies V, designed to determine O2 tolerance of multiple organs and systems in humans at 3.0-1.5 ATA, pulmonary function was evaluated at 1.0 ATA in 13 healthy men before and after O2 exposure at 3.0 ATA for 3.5 h. Measurements included flow-volume loops, spirometry, and airway resistance (Raw) (n = 12); CO diffusing capacity (n = 11); closing volumes (n = 6); and air vs. HeO2 forced vital capacity maneuvers (n = 5). Chest discomfort, cough, and dyspnea were experienced during exposure in mild degree by most subjects. Mean forced expiratory volume in 1 s (FEV1) and forced expiratory flow at 25-75% of vital capacity (FEF25-75) were significantly reduced postexposure by 5.9 and 11.8%, respectively, whereas forced vital capacity was not significantly changed. The average difference in maximum midexpiratory flow rates at 50% vital capacity on air and HeO2 was significantly reduced postexposure by 18%. Raw and CO diffusing capacity were not changed postexposure. The relatively large change in FEF25-75 compared with FEV1, the reduction in density dependence of flow, and the normal Raw postexposure are all consistent with flow limitation in peripheral airways as a major cause of the observed reduction in expiratory flow. Postexposure pulmonary function changes in one subject who convulsed at 3.0 h of exposure are compared with corresponding average changes in 12 subjects who did not convulse.

Adult↗
PubMed1991

Hospice growth.

Explore the source record for details and available documents.

Adult↗
PubMed1991

[The central nervous system of infants born to HIV-positive mothers-- neuropathology, immunohistochemistry in in situ hybridization].

The central nervous system (CNS) of 12 fetuses from human-immunodefiency-virus-seropositive mothers was investigated. Postconceptional ages ranged between 15 and 21 weeks. 3 preterm infants born to HIV positive mothers whose survival ranged from 6 hours to 6 months were included in the study. In all cases, the development of the CNS was macroscopically normal. The microscopic examination showed many ectopic neurons indicating disturbances of normal neuronal migration. As a regular finding there was a significant increase in microglia in all areas of the CNS but no microglial nodules were found. In all cases haematogenous monocytes were scattered in the perivascular space of the cerebral parenchyma as well as in the chorioid pexus. The virus-antigen p24 could neither be detected immunohistochemically in the paraffin sections nor in the frozen material of the brain or by in-situ-hybridization. In contrast, in five of the cases investigated the placenta showed macrophages, socalled Hofbauer cells with p24-associated antigen.

Antigens, Viral↗
PubMed1990

Thermally induced optical property changes in myocardium at 1.06 microns.

Light in the visible and near-infrared region is diffusely scattered in tissues by macromolecules. It was therefore hypothesized that tissue coagulation caused by high-power continuous wave laser irradiation might significantly alter tissue optical properties, resulting in a redistribution of laser energy during the laser ablation process. Infrared transmittance studies confirmed the hypothesis by demonstrating an irreversible decrease in light transmittance (45%) during heating of a 0.75 mm thick slice of tissue. Absorption and scattering coefficients were then determined from transmittance and reflectance measurements on thin slices of raw and coagulated myocardium irradiated with a Nd:YAG laser (1.06 microns). The scattering coefficient was found to increase fourfold (0.427 mm-1----1.74 mm-1) during tissue coagulation, while the absorption coefficient remained relatively unchanged (0.044 mm-1----0.051 mm-1). Calculations indicate that the coagulation-induced changes in tissue optical properties substantially increase surface back-scattering and reduce tissue penetration.

Animals↗
PubMed1990

[Fatal outcome in HELLP syndrome].

The patient was a 32-year-old para 2 who developed within a few hours after the first symptoms a lethal HELLP-syndrome. Despite initially normal blood pressure an hepatic failure, hemolysis and cerebral bleeding appeared. The autopsy revealed an eclamptic liver and symptoms of a disseminated intravasal coagulation (DIC). As a consequence a quick delivery instead of a conservative-expectant management because of fetal prematurity is recommended.

Adult↗