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21.
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
22.
Josef B. Keller 《Plant Systematics and Evolution》1872,22(10):335-337
Ohne Zusammenfassung 相似文献
23.
R Larisch K Kley S Nikolaus W Sitte M Franz H Hautzel W Tress H-W Müller 《Hormones et métabolisme》2004,36(9):650-653
Previous studies on hypothyroid subjects have indicated serious psychiatric symptoms affecting the patients' quality of life. The present prospective cross-sectional study's aim was to examine these symptoms in thyroid patients with different functional states. A total of 254 patients (age: 56 +/- 14 years [mean +/- standard deviation], 181 female, 73 male) referred to a hospital for radioiodine treatment of hyperthyroidism or for follow-up of differentiated thyroid cancer, respectively, were included. All patients underwent the twelve-item general health questionnaire, which is an instrument for detecting mood disturbances. Euthyroid and hyperthyroid patients did not differ significantly in their general health questionnaire score (11 +/- 5 vs. 11 +/- 7), nor did subclinical hyperthyroid (11 +/- 6) or subclinical hypothyroid subjects (12 +/- 5). In contrast, hypothyroid patients showed a significantly higher mean score (17 +/- 7, p < 0.001, ANOVA). Binary logistic regression revealed that hypothyroidism increases age and gender-adjusted risk for critical mood deterioration by seven-fold. Thus, hypothyroidism represents a widely underestimated functional condition that may severely affect mental health. 相似文献
24.
Rates of mutation to growth factor autonomy and tumorigenicity differ in hematopoietic stem and precursor cells expressing the multilineage colony-stimulating factor gene. 总被引:2,自引:0,他引:2
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C Laker N Kluge C Stocking U Just M J Franz W Ostertag J F DeLamarter M Dexter E Spooncer 《Molecular and cellular biology》1989,9(12):5746-5749
At least two separate but interdependent events are required to attain autonomous growth as a consequence of ectopic expression of the multilineage colony-stimulating factor gene in hematopoietic progenitor cells. The rate at which the second event occurs is more than 3 orders of magnitude higher in precursor cell lines (FDC-P1 or FDC-P2) than in stem cell lines (FDC-Pmix). Autonomous, but not density-dependent, growth is tightly coupled to tumorigenicity in precursor cells; however, neither growth-factor-independent nor autonomously growing stem cell lines are tumorigenic. 相似文献
25.
26.
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
27.
Lars-Gunnar Franzén Gerhard Frank Herbert Zuber Jean-David Rochaix 《Plant molecular biology》1989,12(4):463-474
cDNA clones encoding two Photosystem I subunits of Chlamydomonas reinhardtii with apparent molecular masses of 18 and 11 kDa (thylakoid polypeptides 21 and 30; P21 and P30 respectively) were isolated using oligonucleotides, the sequences of which were deduced from the N-terminal amino acid sequences of the proteins. The cDNAs were sequenced and used to probe Southern and Northern blots. The Southern blot analysis indicates that both proteins are encoded by single-copy genes. The mRNA sizes of the two components are 1400 and 740 nucleotides, respectively. Comparison between the open reading frames of the cDNAs and the N-terminal amino acid sequences of the proteins indicates that the molecular masses of the mature proteins are 17.9 (P21) and 8.1 kDa (P30). Analysis of the deduced protein sequences predicts that both subunits are extrinsic membrane proteins with net positive charges. The amino acid sequences of the transit peptides suggest that P21 and P30 are routed towards the lumenal and stromal sides of the thylakoid membranes, respectively.Abbreviations OEE1, 2 and 3
oxygen evolution enhancer proteins 1, 2 and 3
- Rubisco
ribulose bisphosphate carboxylase/oxygenase
- PS
photosystem
- P21 and P30
C. reinhardtii thylakoid polypeptides 21 and 30 相似文献
28.
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
29.
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
30.
Summary In order to demonstrate enzyme activities playing a role in the biosynthesis of cardenolides and 2,6-dideoxysugars, 5H-pregnan-3ol-20-one and cardenolides (digitoxigenin, oleandrigenin/L-oleandrose, oleandrin, neriifolin, digitoxigeninmonodigitoxoside and strospeside) were fed to cell suspension cultures of Nerium oleander L.. It could be shown that cell suspension cultures of Nerium oleander L. are able to oxidize, isomerize and glucosylate 5H-steroidaglycones at C-3. The respective glucosides of the 5H-steroid-aglycones are the main biotransformation products. These cell cultures are an appropriate tool for the production of labelled 5H-steroidglucosides.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- IAA
indole-3-acetic acid
- EtOAc
ethylacetate
- MeOH
methanol
- MS
Murashige & Skoog 相似文献