Increased LH and FSH release from the anterior pituitary of ovariectomized rat, in vivo, by copper-, nickel-, and zinc-LHRH complexes.

1992

Abstract The effect of Cu 2+ , Ni 2+ , Zn 2+ and their complexes with LHRH on the release of luteinizing hormone (LH) and follicle stimulating hormone (FSH) was estimated in in vivo experiments with the use of the method proposed by Ramirez and McCann. Ovariectomized, estradiol, and progesterone pretreated rats were injected intraveneously either with LHRH alone, a metal ion alone, a mixture of metal and hormone, or a metal-LHRH complex. A metal alone or a mixture of it with LHRH did not affect gonadotropin release at all or no more than LHRH alone. However, the complex of Cu 2+ with LHRH brought about a high release of LH and even higher release of FSH. This indicates that copper complex i…

Immunoregulation: studies of physiological and therapeutic autoreactivity by T cell vaccination

1992

Prevalence of Parkinson's disease and other types of parkinsonism: A door-to-door survey in three Sicilian municipalities

1992

We investigated the prevalence of Parkinson's disease and other types of parkinsonism in a Sicilian population using a door-to-door two-phase approach. This design called for the administration of a brief screening instrument to all subjects who, on November 1, 1987, were residents of Terrasini (Palermo Province), Santa Teresa di Riva (Messina Province), and Riposto (Catania Province), Sicily (N = 24,496). Study neurologists using specified diagnostic criteria extensively investigated those subjects who screened positive. We found 63 subjects affected by Parkinson's disease, 21 with secondary parkinsonism, and seven with unspecified parkinsonism. The crude prevalence per 100,000 population …

Proliferation-associated oxygen consumption and morphology of tumor cells in monolayer and spheroid culture.

1992

The oxygen consumption rate, proliferative activity, and morphology of EMT6/Ro mouse mammary sarcoma cells in monolayer and multicellular spheroid culture have been investigated in a comparative study. During the transition of monolayer cells from the exponential into the plateau growth phase, there is a distinct decrease in the cellular volume that is associated with a corresponding decrease in the proliferative and respiratory activity of the cells. The decline in cell volume is mainly due to a decrease in the content of cytoplasm, whereas the size of the nucleus is only slightly reduced. A concomitant decrease in the number of mitochondria per cell obviously accounts for the reduction in…

Immunohistochemistry of cholinergic receptors.

1992

Acetylcholine and its receptors are involved in a variety of important signal transduction processes. As shown here paradigmatically for the human neuromuscular junction and the cerebral cortex, acetylcholine receptors can be visualized immunohistochemically at the cellular and subcellular level under physiological and pathological conditions. At normal motor endplates nicotinic cholinoceptors are localized at the surface of the postsynaptic junctional folds. In myasthenic syndromes investigation of muscle biopsies enables the diagnosis of receptor deficiencies at the ultrastructural level. In normal cerebral cortex pyramidal neurons are equipped with both nicotinic and muscarinic acetylcho…

Evaluation of soluble CD 14 and neopterin as serum parameters of the inflammatory activity of pulmonary sarcoidosis.

1992

CD14 represents the most specific marker for monocytes/macrophages. It has been demonstrated in vitro that monocytes/macrophages lose this antigen upon activation. Results of studies investigating the expression of membrane-bound CD14 on the surface of monocytes/macrophages in sarcoidosis patients are controversial. To investigate whether the soluble form of CD14 reflects monocyte/macrophage activation in sarcoidosis, serum levels of soluble CD14 were determined concurrently with other serum markers of monocyte/macrophage activation (neopterin, angiotensin-converting enzyme) in 50 consecutive patients with bioptically confirmed sarcoidosis. The patients were allocated to three groups accord…

Erwinia carotovora subsp. odorifera subsp.nov., associated with odorous soft rot of chicory (Cichorium intybus L.)

1992

Eleven strains of Erwinia carotovora that were isolated mainly, but not exclusively, from slimy rot of witloof chicory and were previously designated “atypical” E. carotovora subsp. atroseptica strains were characterized and compared with strains of E. carotovora subsp. carotovora, E. carotovora subsp. atroseptica, and Erwinia chrysanthemi (including the type strains). The 11 atypical E. carotovora subsp. atroseptica strains produced a typical bananalike odor when they were inoculated onto witloof chicory leaves. DNA-DNA homology experiments, biochemical tests, tests to determine carbon utilization patterns, and tests to identify the volatile metabolites produced from rotting witloofs were …

Influence of stoichiometry on high temperature intrinsic defects in fused silica

1992

Abstract The set of intrinsic defects, their generation, interactions and recombination reactions are discussed, including the participation of atomic and molecular oxygen, which allows one to take into account the stoichiometry of fused silica. The mathematical solution of the set of equations, which characterizes the equilibrium concentrations of intrinsic defects, gives the specific values of intrinsic defect concentrations at different temperatures and stoichiometries. The influence of such intrinsic defects frozen in at room temperature on the spectroscopic characteristics of fused silica is analyzed.

Sub-acute effects of interferon-α2 on adrenocorticotrophic hormone, cortisol, growth hormone and prolactin in humans

1992

Abstract This study investigated the chronic effects of interferon-α2 (IFN-α2) on hormonal secretion in humans. Six patients suffering from chronic hepatitis B or C infection received SC doses of 3 million IU IFN-α2 three times a week for 4 mo. Each patientwas examined for hormone secretion four times: the day before initial IFN-α2 administration (day 0), the day of the first injection (day 1), and 4 wk after start of IFN therapy on days 27 (without IFN administration) and 28 (with IFN administration). Adrenocorticotrophic hormone (ACTH), cortisol, growth hormone (hGH), and prolactin (PRL) were measured in plasma samples drawn at 30-min intervals between 1600h and 2400h. Acute administratio…

Quantification of exposure to dioxins and furans in a cohort of workers of a herbicide producing plant in hamburg, FRG

1992

Abstract To assess the exposure to PCDD/Fs of a cohort of 1583 workers of a herbicide producing plant in Hamburg, FRG, investigated for cancer mortality, measurements of PCDD/Fs in fat tissue (n=48) or blood (n=64) were analyzed according to work histories in a subgroup of n=112 male workers. In a multiple regression analysis the time of work in the production of 2,4,5-T and 2,4,5-TCP, for the latter especially before 1957, correlated well with the levels of 2378-tetrachlorodibenzo-p-dioxin (TCDD). For most of the higher chlorinated isomers time of work in the thermic decomposition showed the strongest effect. The results confirm that the developed indicators are good proxis for exposure to…

Lp(a) levels in patients undergoing aorto-coronary bypass surgery.

1992

The aims of this study were to evaluate plasma lipid, apoprotein and Lp(a) levels in patients with severe coronary atherosclerosis undergoing aorto-coronary bypass surgery (BP) and to relate these parameters to the involvement of one or more vessels. Seventy-seven male patients and 77 cardiovascular disease-free controls, matched for sex, age and body weight were studied. Higher triglyceride and apo B levels with lower HDL-cholesterol and apo A-I levels were found in BP patients in comparison with the controls. Lp(a) levels were slightly, but not significantly, increased. Moreover BP patients presented a significantly higher prevalence of HDL-cholesterol levels below 35 mg dl-1 (49.3% vs 22…

Magnetostrictive and quadrupolar anisotropy in nuclear magnetic fcc systems

1992

The spin hamiltonian for nuclear magnetic order in copper is investigated with respect to magnetoelastic couplings to the lattice. These arise due to the dipolar, Ruderman Kittel and the quadrupolar interaction. While the latter is quenched for the ideal fcc-lattice, it is found that for copper it will dominate the magnetoelastic terms of the nuclear spin hamiltonian. The absolute size of the quadrupole contribution is determined by the effective charge and (anti-) shielding effects. This interaction can give rise to an effective anisotropy in the fcc-system which can be quite large compared to the small stabilisation energies for nuclear order in copper. Consequences for the nuclear orderi…

Modelling Offices Through Discourse Analysis: A Comparison and Evaluation of SAMPO with OSSAD and ICN

1992

In a previous paper the importance of framing office communications in terms of discourse analysis was explored. 2 It also presented an approach based on speech acts and conversations to allow this framing to occur. The approach was termed SAMPO. In this paper, we continue the discussion on discourse analysis by comparing SAMPO with two prominent office modelling approaches, Information Control Nets (ICN) and OSSAD, and discuss its merits in modelling office communications.

Early development of human Merkel cells.

1992

Human fetal Merkel cells are now generally considered to be epidermal derivatives. Previous studies using antibodies against the simple epithelial cytokeratins (CKs), 8 and 18, have demonstrated the presence of these cells in the epidermis at as early as fetal week 10 to 12. Using antibodies against CK 20 whose expression within the skin is restricted to Merkel cells, we applied immunofluorescence and immunoperoxidase microscopy to analyze earlier embryonic and fetal human skin (wk 7 to 9). We were able to demonstrate the first Merkel cells at as early as fetal wk 8, i.e., at the same time as the epidermis starts to develop an intermediate, third layer, characterized by the expression of CK…

Volcanic steam output directly measured in fumaroles: the observed variations at Vulcano Island, Italy, between 1983 and 1987

1992

The mass of steam emitted by the fumaroles of the crater of Vulcano (Aeolian Islands, Italy) was evaluated by using a direct measuring method. Measurements were effected with this method between 1983 and 1987 in nine field campaigns, the results of which are given in this paper. The steam flux measurements were performed by an instrument expressly designed for steam condensation. The estimates of the thermal energy transported daily by the steam gave values of up to 10E12 J. The sharp variations in the total mass outputs recorded in 1984 and 1985 are here interpreted as being a consequence of the probable accumulation of fluid pressure at depth, during the evolution of volcanic activity. Th…

Surface-directed spinodal decomposition: Phenomenology and numerical results.

1992

We present a phenomenological theory for surface effects on spinodal decomposition in mixtures and related phenomena such as the dynamics of surface segregation. Numerical solutions of our equations show striking similarity to recent results from experiments on polymer mixtures with one component preferentially attracted to a wall.

The self-couplings of vector bosons: does LEP-1 obviate LEP-2?

1992

Abstract Theories beyond the standard model (“meta-theories”) are severely constrained by the current body of data and must necessarily respect the standard gauge symmetry. We analyze the constraints on two generic types of meta-theory, in which fundamental scalar do or do not exist. The novel low-energy effects can be comprehensively described by grafting onto the standard lagrangian new operators that - in the sense of a Taylor expansion - form a complete set. Completeness calls for consideration of previously discarded operators, and for a thorough exploitation of the equations of motion. We illustrate the current strictures by focusing on the allowed range of departures from the most cr…

Biochemistry. Von C. K. Mathews und K. E. van Holde. The Benjamin/Cummings Publishing Co. Inc., Redwood City, CA (USA), 1990. XXIX, 1129 S., geb. $ 4…

1992

In vitro effects of putative neurotransmitters on synaptic ribbon numbers and N-acetyltransferase activity in the rat pineal gland

1992

The pineal contains a large number of classical transmitters and neuropeptides. Some of these neurochemicals are involved in the regulation of serotonin N-acetyltransferase (NAT) activity and hence in melatonin synthesis. Synaptic ribbons present in the pineal gland also exhibit a numerical day/night rhythm parallel to that of NAT activity. There is scarcity of information regarding the regulation of synaptic ribbon (SR) numbers. In the present study, we have investigated in vitro effects of a number of classical neurotransmitters and neuropeptides. NAT activity was used to monitor melatonin synthesis under the experimental conditions used. Norepinephrine (NE), Delta sleep-inducing peptide …

Relationships between oxygen concentration and patterns of energy metabolism in the rotifer Brachionus plicatilis

1992

Abstract 1. 1. Activities of 10 enzymes and accumulation of two metabolites under experimental hypoxia were investigated in the rotifer Brachionus plicatilis . 2. 2. Pyruvate kinase (PK), lactate dehydrogenase (LDH), malic enzyme (ME), phosphoenolpyruvate carboxykinase (PEPCK), malate dehydrogenase (MDH) and fumarase (FUM) activities showed great increase at low oxygen levels. Alcohol dehydrogenase (ADH) activity was not detected. 3. 3. Alanine concentration showed an increase with low oxygen concentrations, while alanine aminotransferase (GTP) showed a slight activity increase with oxygen levels. The high alanine concentration was interpreted as enhanced proteolysis. 4. 4. Our results show…

A simple microsuperspace model in 2 + 1 spacetime dimensions

1992

Abstract We quantize the closed Friedmann model in 2 + 1 spacetime dimensions using euclidean path-integral approach and a simple microsuperspace model. A relationship between integration measure and operator ordering in the Wheeler-DeWitt equation is found within our model. Solutions to the Wheeler-DeWitt equation are exactly reproduced from the path integral using suitable integration contours in the complex plane.

99mTechnetium-Mercaptoacetyltriglycin (MAG3) zum Nachweis von Nierenveränderungen nach extrakorporaler Stoßwellenlithotripsie

1992

Extracorporeal shock wave lithotripsy (ESWL) has become the treatment of choice for urinary calculi. 117 patients were studied prospectively with 99mTc mercaptoacetyltriglycine (MAG3) before and after ESWL. 79 (66%) of the 119 kidneys treated had abnormal findings. Of these 63/119 (53%) had abnormal scans. 41 (65%) had focal lesions with a delayed intrarenal transport. The remaining 22 had a diffuse delay of intrarenal transport. A loss of relative renal function of 3% and more compared to the pretreatment values was observed in 50/119 (42%) patients. 99mTc MAG3 should be done routinely together with radiologic tests (CT or MRI) before and after ESWL to select the patients at risk for post …

Autophagy, cathepsin L transport, and acidification in cultured rat fibroblasts.

1992

The mechanisms of enzyme delivery to and acidification of early autophagic vacuoles in cultured fibroblasts were elucidated by cryoimmunoelectron microscopic methods. The cation-independent mannose-6-phosphate receptor (MPR) was used as a marker of the pre-lysosomal compartment, and cathepsin L and an acidotropic amine (3-(2,4-dinitroanilino)-3'-amino-N-methyl-dipropylamine (DAMP), a cytochemical probe for low-pH organelles) as markers of both pre-lysosomal and lysosomal compartments. In addition, cationized ferritin was used as an endocytic marker. In ultrastructural double labeling experiments, the bulk of all the antigens was found in vesicles containing tightly packed membrane material…

Isoelectronic series of twofold coordinated Si, Ge, and Sn atoms in glassy SiO2: a luminescence study

1992

Abstract Luminescence centers causing optical absorption bands in the 5 eV region in oxygen-deficient pure (‘Si-doped’), as well as in Ge- and Sn-doped glassy SiO2 were studied. The spectral and particularly kinetic data show that in all cases luminescence centers with closely similar properties exist which constitute an isoelectronic series. They are attributed to defects, formed by electrically neutral twofold coordinated Si, Ge, and Sn atoms (T20 centers) in glassy SiO2. Twofold coordinated Si causes the characteristic ‘B2’ optical absorption band at 5.03 eV. Upon reaction with atomic hydrogen, T20 centers convert to the well known ‘H(I)’, ‘H(II)’ and ‘H(III)’ ESR-active defects. The alt…

Effect of local ischemia on induction of cardiac reentries

1992

In this paper, we study the effects of local ischemia on the process of triggering of reentry mechanism. We present computer simulations based on a cellular automata model of the propagation of the depolarizing wave through a ventricular surface element. We simulate a local area of ischemia where effects of refractory period dispersion are investigated. We use a gaussian distribution of the refractory periods characterized by a mean value and a standard deviation. These simulations show that there exist critical conditions necessary to initiate a reentry mechanism invading progressively the whole ventricle.

Heavy quark symmetry at large recoil

1992

Abstract We analyze the large recoil behaviour of heavy meson transition form factors using the Brodsky-Lepage hard scattering formalism. At the leading order of the heavy mass scale the large recoil form factors exhibit a new type of heavy quark symmetry. We discuss next-to-leading mass effects and present explicit 1/MQ expressions for the form factors in the peaking approximation.

The interaction of organotins with native DNA

1992

The compounds R2SnCl2 and R3SnCl (RMe, Et, nBu, nOct, Ph, in ethanol solution) as well as the aqueous species [Me2Sn(OH2)n]2+ and [Me3Sn(OH2)2]+, react with aqueous native DNA, yielding solid phases. According to the pointcharge model treatment of the 119Sn Mossbauer parameter nuclear quadrupole splitting, trans-octahedral R2Sn(O2PXY)2, and trigonalbipyramidal R3Sn(O2PXY), (RMe, Et, nBu), would occur in the pellets, the tin atoms being coordinated by phosphodiester groups of the nucleic acid. The precipitates from Ph2SnIV would consist of the DNA complex as well as of the Ph2SnIV distannoxane obtained by hydrolysis of the reactant, whilst nOct2SnCl2, nOct3SnCl and Ph3SnCl would mainly yield…

LASER SPECTROSCOPY WITH A COOLER RING AT THE ESR (GSI) AND THE TSR (MPI HEIDELBERG)

1992

At the TSR cooler ring at Heidelberg, laser studies were carried out using singly charged lithium and beryllium ions. Laser spectroscopy of relativistic lithium ions (v=0.04c) yielded signals with a narrow linewidth, suitable for an experimental test of special relativity. A dramatic reduction of the beam temperature, as defined by the longitudinal velocity spread, was achieved via laser cooling in both cases. At the ion energies available at ESR it will become possible to prepare and store bare ions up to U92+. Electron cooling was succesfully demonstrated for hydrogen-like Bi82+ ions, where a laser experiment is scheduled to study the ground-state hyperfine splitting.

MONTE CARLO METHODS FOR FIRST ORDER PHASE TRANSITIONS: SOME RECENT PROGRESS

1992

This brief review discusses methods to locate and characterize first order phase transitions, paying particular attention to finite size effects. In the first part, the order parameter probability distribution and its fourth-order cumulant is discussed for thermally driven first-order transitions (the 3-state Potts model in d=3 dimensions is treated as an example). First-order transitions are characterized by a minimum of the cumulant, which gets very deep for large enough systems. In the second part, we discuss how to locate first order phase boundaries ending in a critical point in a large parameter space. As an example, the study of the unmixing transition of asymmetric polymer mixtures…

Biomonitoring of heavy metal distribution in the Western Mediterranean area of Spain

1992

Changes in Serum and Lipoprotein Fatty Acids of Growing Rats Fed Protein-Deficient Diets with Low or Adequate Linolenic Acid Concentrations

1992

The effects of a protein-deficient diet associated with sunflower oil [adequate in 18:2(n-6), poor in 18:3(n-3)] or soybean oil [adequate in both 18:2(n-6) and 18:3(n-3)] on lipid serum and lipoprotein compositions were studied in growing rats. Four groups of rats were fed different diets: SFC (20% casein + 5% sunflower oil); SFd (2% casein + 5% sunflower oil); SC (20% casein + 5% soybean oil); Sd (2% casein + 5% soybean oil). After 28 d, both protein-deficient groups exhibited low concentrations of protein, phospholipid, triacylglycerol and total cholesterol in serum and VLDL. Compared with rats fed 20% casein diets, those fed low protein diets had lower 18:2(n-6) and 20:4(n-6) in phosphol…

Fos-like expression and nuclear size in osmotically stimulated supraoptic nucleus neurons

1992

This study has analysed by immunocytochemistry the pattern of expression of Fos-related proteins, as well as variations in nuclear size, after the osmotically induced activation of supraoptic nucleus neurons of the rat. In control rats most supraoptic nucleus neurons were Fos-like negative. After acute and chronic dehydration by salt-loading, the number of Fos-like positive neurons increased dramatically. The level of Fos-like immunoreactivity was higher in chronically stimulated rats, and also the neurons of the ventral region of the supraoptic nucleus were more intensely stained than those of the dorsal region. The karyometric analysis was made on electron micrographs. The mean nuclear pr…

Primary culture of single ectodermal precursors of Drosophila reveals a dorsoventral prepattern of intrinsic neurogenic and epidermogenic capabilitie…

1992

ABSTRACT We have analyzed the development in vitro of individual precursor cells from the presumptive truncal segmental ectoderm of the Drosophila embryo to study the intrinsic component in the determination of cell fate. For each cultured cell, the original position within as well as the developmental stage of the donor embryo were known. Cells removed from the ventral neurogenic region develop neural clones. Cells from the dorsal ectoderm and from the dorsalmost part of the ventral neurogenic ectoderm develop epidermal clones. These two classes of clones differ with respect to their division pattern, adhesiveness, cell morphologies and the expression of cell-specific markers. Mixed neural…

The correlation of the 7.6 eV optical absorption band in pure fused silicon dioxide with twofold-coordinated silicon

1992

Abstract The optical absorption band at 7.6 eV, which appears in oxygen deficient pure silica, does not correlate with any ESR signal in non-irradiated samples. Longlasting illumination at 80 K in the range of its absorption leads to an increase of the absorption band at 5 eV. Subsequent heating to 290 K restores the initial absorption. These data can be explained as photodissociation and thermal recreation of a complex defect containing a twofold-coordinated silicon defect. This complex defect is responsible for the 7.6 eV absorption band.

Increased expression of ICAM-1, E-selectin, and VCAM-1 by cultured human endothelial cells upon exposure to haptens.

1992

Contact allergens induce several accessory signals which promote the activation of antigen-specific T cells. One of these signals is the increased expression of adhesion molecules on antigen-presenting cells and endothelial cells. Epicutaneous application of non-toxic doses of 2,4-dinitrofluorobenzene (DNFB) onto the skin of non-sensitized individuals elicited progressive staining for ICAM-1 on dermal microvascular endothelial cells. To elucidate the question of whether contact allergens can act directly on endothelial cells to elevate their expression of surface structures that bind leukocytes, confluent monolayers of human umbilical vein endothelial cells were incubated with the contact a…

DNA image cytometry in stomach carcinoma. Its relation to histomorphologic parameters and its influence on prognosis

1992

BACKGROUND The influence of DNA content on the prognosis in stomach cancer is controversial. METHOD After curative resection of stomach carcinomas (adenocarcinomas [n = 58]; signet ring cell carcinomas [n = 24]; undifferentiated carcinomas [n = 21]), the influence of the DNA content and histomorphologic parameters on the prognosis was examined. RESULTS In the multivariate regression analysis, the prognosis depended on the lymph node status (P = 0.0009), pT stage (P = 0.02), tumor localization (P = 0.03), and histologic type (P = 0.05). The prognosis was independent of the DNA content. Furthermore, the degree of differentiation, operative procedure, safety distance, size of the tumor, and se…