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11.
Frank Josef Mller Oliver Zierau Torsten Hertrampf Anja Bliedtner Patrick Diel Günter Vollmer 《The Journal of steroid biochemistry and molecular biology》2009,113(3-5):296-303
Isoflavones (ISOs) are bioactive food ingredients of the traditional East Asian diet and currently discussed as alternatives to classical hormone replacement therapies and for reducing the prevalence of hormone-dependent cancers. Although there are many studies on ISOs, not much is known about their long-term effects.Therefore, we performed an animal experiment analyzing the effects of three different diets: a phytoestrogen-free diet, a diet supplemented with genistein (700 μg/g diet) and an ISO-high diet (232 μg daidzein and 240 μg genistein/g) at two distinct time points, juvenile (21 days) and adult (97 days). Exposure started prior to mating of the parents and throughout the life of the offspring.We observed a stronger increase of uterine wet weights in juvenile offspring with genistein exposure (1018 ± 350 mg/kg BW) than with ISO-high diet (497 ± 133 mg/kg BW). Whereas the expression of proliferation related genes (PCNA; Ki67; IGF-1; IGF-1R), analyzed by real-time-qPCR and Western blot, were significantly down-regulated in juvenile animals exposed to genistein. Additionally, genistein exposure led to estrogenic responses, observed upon increase of complement C3 and decrease of estrogen receptors gene expressions, while the exposure to ISO-high diet did not show these effects.In conclusion, both the time point on which phytoestrogen exposure starts together with the composition of the ingested phytoestrogen containing diet are of great importance for the biological response of the offspring. 相似文献
12.
Josef B. Keller 《Plant Systematics and Evolution》1872,22(10):335-337
Ohne Zusammenfassung 相似文献
13.
Role of cytotoxic T lymphocytes in the prevention of lupus-like disease occurring in a murine model of graft-vs-host disease 总被引:11,自引:0,他引:11
C S Via S O Sharrow G M Shearer 《Journal of immunology (Baltimore, Md. : 1950)》1987,139(6):1840-1849
The inoculation of B6D2F1 mice with T lymphocytes from the C57BL/6 parental strain induces an "immunosuppressive" graft-vs-host reaction (B6 GVH), whereas inoculation of T cells from the other, DBA/2 parental strain induces an "immunostimulatory" GVH reaction and a lupus-like disease (DBA GVH). The present study compares cytotoxic T lymphocyte (CTL) function in the spleens of these GVH mice as well as differences in the donor inoculum that could account for these different types of GVH. We observed that the B6 GVH induces an immunodeficiency that encompasses CTL precursors (and possibly T helper cells) and results in suppressor cells that abrogate responses to both trinitrophenyl (TNP)-modified self and third party alloantigens. In contrast, the DBA GVH induces only a T helper cell immunodeficiency and results in suppressor cells selective for class II restricted L3T4+ T helper cells. Chimeric T cells were detected in both types of GVH. In the B6 GVH both L3T4+ and Lyt-2+ donor cells were observed, although Lyt-2+ cells predominated. In the DBA GVH, donor T cells were almost exclusively of the L3T4+ phenotype. The lack of appreciable donor Lyt-2+ cells in the DBA GVH can be explained by a defect in the DBA donor inoculum manifested by a naturally occurring two-fold reduction in Lyt-2+ cell numbers as well as a nine-fold reduction in CTL precursors with anti-F1 specificity. T cells in the DBA inoculum, therefore, are predominantly L3T4+. A similar defect induced in B6 donor cells by anti-Lyt2 antibody and complement not only converted the suppressive GVH to a stimulatory GVH, as measured by anti-DNA antibodies, but also resulted in a T cell immune deficiency characteristic of the DBA GVH, i.e., a selective loss of the TNP-self CTL response. Thus the presence or absence of adequate numbers of functioning Lyt-2+ cells in the donor inoculum is correlated with the development of either a suppressive or stimulatory GVH, respectively. That donor Lyt-2+ cells mediate a suppressive GVH through cytolytic mechanisms is evidenced by greater than 70% reduction in B6 GVH spleen cell numbers and readily demonstrable anti-F1 CTL activity by these spleen cells despite an inability to generate anti-allogeneic or anti-TNP self CTL activity even in the presence of added T helper factors.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
14.
Karl H. Summer Dominik Klein Nada de Ruiter Josef Abel 《Biological trace element research》1989,21(1):165-169
In the present study we report on the effects of commonly used nonsteroidal antiinflammatory drugs on metallothionein (MT)
and MT-I mRNA levels. A single dose of chloroquine (100 mg/kg), diclofenac (100 mg/kg), indomethacin (10 mg/kg), or piroxicam
(100 mg/kg) was administered ip to C57B1 mice. After 18 h, MT levels were determined with a Cd-saturation radioassay. MT-I
mRNA levels were measured by Northern Blot analyses using a probe containing the mouse MT-I gene. All drugs tested caused
an increase in the MT content of the liver but not of the kidneys and lung. The lowest and highest effects were observed with
chloroquine (8 times the control value) and diclofenac (18 times), respectively. In accordance with the stimulation of MT
synthesis, increased accumulation of hepatic MT-I mRNA could be demonstrated.
These results indicate that elevated MT levels may contribute to the effectiveness of nonsteroidal antiinflammatory drugs
in the treatment of rheumatoid arthritis (RA). 相似文献
15.
Effects of age and physical performance capacity on distribution and composition of high-density lipoprotein subfractions in men 总被引:1,自引:0,他引:1
Ingrid Frey Aloys Berg Manfred W. Baumstark Klaus-Günther Collatz Josef Keul 《European journal of applied physiology and occupational physiology》1990,60(6):441-444
The influences of age and maximal aerobic capacity (VO2max) on serum lipoproteins with special regard to the concentration, composition and distribution of high density lipoprotein (HDL) subfractions were investigated in 51 healthy males of different characteristics: younger than 35 years, untrained (n = 14, mean age 28.2 years, SD 6.0; VO2max, 47.9 ml.kg-1.min-1, SD 5.8) and trained (n = 11, mean age 27.9 years, SD 4.3; VO2max, 61.1 ml.kg-1.min-1, SD 5.1), older than 50 years untrained (n = 14, mean age 58.9 years, SD 5.9, VO2max, 29.3 ml.kg-1.min-1, SD 5.3) and trained (n = 12, mean age 59.3 years, SD 7.2, VO2max, 45.7 ml.kg-1.min-1, SD 7.7). The fasting-state serum concentrations of total cholesterol, tri-acylglycerol and lipoprotein-cholesterol were measured. The HDL-subfractions were separated by density (rho) gradient ultracentrifugation. Concentrations of cholesterol, cholesterylester, tri-acylglycerol, phospholipids, apolipoprotein (apo) A-I and A-II were measured in the subfractions HDL2b: rho = 1.063-1.100 g.ml-1; HDL2al: rho = 1.00-1.110 g.ml-1; HDL2a2: rho = 1.110-1.150 g.ml-1; HDL3: rho = 1.150-1.210 g.ml-1. Elderly untrained subjects showed increased serum concentrations of total-, very low- and low density lipoprotein-cholesterol and elevated tri-acylglycerol levels. The HDL-cholesterol concentration was decreased, due to reduced concentrations of HDL2-subfractions. Significant changes in the composition of HDL2-subfractions were found in elderly untrained subjects. The HDL2-subfractions had more protein, a decreased apoA-I:A-II ratio and less phospholipids in comparison to HDL2-subfractions from younger untrained and trained, and elderly trained subjects.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
16.
Summary Immunohistochemical properties of the terminal nerve network in the rat heart were assessed by use of the elution-restaining method. The colocalization of the enzymes involved in catecholamine synthesis (tyrosine hydroxylase — TH, dopamine--hydroxylase — DBH) as well as the respective distributions of the neuropeptides associated with the adrenergic nervous system (neuropeptide tyrosine — NPY, C-terminal flanking peptide of neuropeptide Y — C-PON) were studied in series of serial sections throughout the interatrial septum and the atrioventricular junction. Our data suggest that ganglion cells of sulcus terminalis as well as the epicardial ganglia enclosed between the superior vena cava and ascending aorta are VIP- and TH-negative, but neuropeptide Y- and DBH-immunoreactive. They give rise to three intraseptal nerves directed towards the specialised structures of the atrioventricular junction. These nerve fascicles contain abundant, thick TH-immunoreactive nerve fibres and scarce, thin NPY- and DBH-immunoreactive fibres. The cell bodies of the intramural ganglion cells localized between the right and left branches of the bundle of His (Moravec and Moravec 1984) are strongly TH- and DBH-immunoreactive. They are innervated by thick nerve fibres having the same immunohistochemical properties (NPY- and DBH-immunoreactivities) as those of a subpopulation of the epicardial ganglion cells and seem to supply some of the TH-immunoreactive nerve fibres directed via the intraseptal nerves to the epicardial ganglia. The existence of a multicomponent nerve network, characterized by a reciprocal innervation of the sinus node and atrioventricular node areas, is suggested by our immunohistochemical data. 相似文献
17.
Summary We describe a previously unreported glucose-6-phosphate dehydrogenase (G6PD) variant. G6PD Huntsville was found in a Caucasian male, resident of Huntsville, Alabama who was investigated for otherwise unexplained chronic hemolytic anemia. An unusual feature of this unique, apparently hemolytic, G6PD mutant is that its red cell enzymatic activity has not been decreased. The mutant enzyme is unstable. Additionally, the enzyme variant is characterized by normal electrophoretic mobility, biphasic and slightly alkaline pH optimum, and abnormal kinetics for the natural substrates G6PD and NADP as well as the artificial substrates deamino NADP. Its activity for another artificial substrate 2-deoxy G6PD is normal. The inhibition constant for NADPH is normal. The subject has had no evidence of episodic jaundice. 相似文献
18.
Elisabeth Stenzel Josef Heni Horst Rimpler Dieter Vogellehner 《Plant Systematics and Evolution》1988,159(3-4):257-271
Cluster analyses by different methods and a minimum spanning tree were used to study phenetic relationships in the genusChlerodendrum. 129 species were scored for 52 morphological characters corresponding to 119 character states. The phenetic results suggest a classification into 7 distinct groups, which may be grouped into two subgenera. This classification is supported by the iridoid distribution as well as by some phylogenetic considerations. 相似文献
19.
20.
Stephen P. Baker Kelly M. Standifer Christopher J. Kalberg Josef Pitha Colin Sumners 《Journal of neurochemistry》1988,50(4):1044-1052
The effects of bromoacetylaminomenthylnorepinephrine (BAAN) on the sodium-dependent, high-affinity norepinephrine (NE) uptake system in rat brain synaptosomes and CNS neuronal cultures were investigated. BAAN inhibited [3H]NE uptake into synaptosomes in a dose- and time-dependent manner (IC50, 6.5 microM). Pretreatment of cortical synaptosomes or neuronal cells with BAAN alone, followed by washing to remove free drug, reduced the Vmax but did not alter the Km value for [3H]NE uptake. The BAAN-induced reduction in Vmax was attenuated by concurrent pretreatment with desipramine and blocked by the reaction of BAAN with dithiothreitol or cysteine. In contrast, BAAN was 19-fold less potent at inhibiting [3H]dopamine uptake in striatal synaptosomes, and no change in the Vmax or Km value for [3H]dopamine uptake was observed after a pretreatment with BAAN followed by washing. Furthermore, the irreversible beta-antagonist, bromoacetylalprenololmentane, was equipotent to BAAN for inhibiting [3H]NE uptake into cortical synaptosomes, but did not alter the Vmax or Km for [3H]NE after pretreatment. In neuronal cultures, BAAN inhibited sodium-dependent uptake of [3H]NE (IC50, 5.6 microM) with no effect on sodium-independent uptake. After pretreatment of cultures with 30 microM BAAN followed by washing, there was a 74% decrease in the Vmax for [3H]NE uptake. Following a 24-h lag period, uptake recovered to the control level within 48 h; however, recovery was completely blocked by cycloheximide. The data indicate that BAAN irreversibly binds to the [3H]NE uptake system in both CNS synaptosomes and neuronal cultures and may be a useful probe for studying the turnover of the [3H]NE uptake system. 相似文献