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61.
62.
K. Linde G. Ramirez C. D. Mulrow A. Pauls W. Weidenhammer D. Melchart 《BMJ (Clinical research ed.)》1996,313(7052):253-258
OBJECTIVE--To investigate if extracts of Hypericum perforatum (St John''s wort) are more effective than placebo in the treatment of depression, are as effective as standard antidepressive treatment, and have fewer side effects than standard antidepressant drugs. DESIGN--Systematic review and meta-analysis of trials revealed by searches. TRIALS--23 randomised trials including a total of 1757 outpatients with mainly mild or moderately severe depressive disorders: 15 (14 testing single preparations and one a combination with other plant extracts) were placebo controlled, and eight (six testing single preparations and two combinations) compared hypericum with another drug treatment. MAIN OUTCOME MEASURES--A pooled estimate of the responder rate ratio (responder rate in treatment group/responder rate in control group), and numbers of patients reporting and dropping out for side effects. RESULTS--Hypericum extracts were significantly superior to placebo (ratio = 2.67; 95% confidence interval 1.78 to 4.01) and similarly effective as standard antidepressants (single preparations 1.10; 0.93 to 1.31, combinations 1.52; 0.78 to 2.94). There were two (0.8%) drop outs for side effects with hypericum and seven (3.0%) with standard antidepressant drugs. Side effects occurred in 50 (19.8%) patients on hypericum and 84 (52.8%) patients on standard antidepressants. CONCLUSION--There is evidence that extracts of hypericum are more effective than placebo for the treatment of mild to moderately severe depressive disorders. Further studies comparing extracts with standard antidepressants in well defined groups of patients and comparing different extracts and doses are needed. 相似文献
63.
Roberta Pierattelli Lucia Banci D. L. Turner 《Journal of biological inorganic chemistry》1996,1(4):320-329
The chemical shifts of several 13C nuclei positioned α to the haems in oxidised cyanide complexes of horseradish peroxidase and lignin peroxidase are reported and analysed in terms
of π molecular orbitals with perturbed D4h symmetry. The additional contributions to the paramagnetic shifts of 13C nuclei in the vinyl groups which arise from conjugation with the porphyrin π molecular orbitals are discussed, and an empirical correction factor is derived from a number of other compounds which contain
haems b. The orbital mixing parameter which is obtained from the analysis of the experimental 13C shifts is compared with the orientation of the axial histidine ligands in X-ray structures of related compounds and found
to be close to the orientation of the normal to the histidine ring. Comparison with the magnetic axes determined by fitting
the dipolar shifts of several protons which have been assigned previously also shows close agreement with the negative in-plane
rotation of the magnetic y axis. It is therefore possible to obtain the approximate orientation of the magnetic axes from 13C resonances of the haem and hence to determine the dipolar shifts at any point in space with respect to the haem by using
these axes together with the anisotropy of the magnetic susceptibility, which can be obtained by extrapolation from EPR g values. Excellent agreement is found between dipolar shifts obtained by fitting an empirical magnetic susceptibility tensor
and predictions based on 13C NMR and EPR in the case of lignin peroxidase. The agreement is less good in the case of horseradish peroxidase, in which
the empirical magnetic z axis appears to be tilted significantly away from the haem normal, though this may be due in part to the lack of accurate
atomic coordinates. It is concluded that useful estimates of the magnetic susceptibility tensor may be obtained from 13C NMR and EPR studies even in large mammalian peroxidases for which no structural models are available.
Received: 27 December 1995 / Accepted: 17 April 1996 相似文献
64.
Alberto M. Martelli Lucia Manzoli Silvia Rubbini Anna Maria Billi Renato Bareggi Lucio Cocco 《Biology of the cell / under the auspices of the European Cell Biology Organization》1995,83(1):15-22
Summary— Using two-dimensional polyacrylamide gels stained with Coomassie blue we have studied the protein composition of the nuclear matrix obtained from mouse erythroleukemic nuclei kept at O°C throughout the isolation procedure to prepare the high ionic strength resistant fraction (control matrix) or stabilized in vitro or in vivo by different procedures prior to subfractionation (ie 37°C incubation of isolated nuclei; sodium tetrathionate exposure of purified nuclei; heat shock of intact cells). When the matrix obtained from 37°C incubated nuclei was compared with the control matrix, striking differences in the polypeptide pattern were seen if the protein was obtained in both cases from an equivalent number of nuclei. On the other hand, if the same amount of protein for both the samples was applied to the gels the differences were less evident. Sodium tetrathionate stabilization of isolated nuclei and heat shock of intact cells produced a matrix protein pattern that was very similar and differed from that of the in vitro heat-exposed matrix. Using specific polyclonal antisera, we demonstrate that nucleolar proteins B23/numatrin and C23/nucleolin were very abundant in the matrix obtained from chemically-treated nuclei or in vivo heat-stabilized nuclei but were recovered in very small amounts (B23) or completely absent (C23) in the matrix prepared from nuclei heated to 37°C in vitro. Differences were seen also in the recovery of nuclear lamins, and especially lamin B, that was poorly represented in the sodium tetrathionate-stabilized matrix. The results demonstrate that in mouse erythroleukemia cells the increased recovery of nuclear matrix protein that is seen after in vitro heating of isolated nuclei is predominantly due to an additional recovery of the same types of polypeptides that are detected also in the absence of such a treatment. The data also indicate that in vivo heat shock of intact cells produces a nuclear matrix protein pattern that is more similar to the pattern seen after stabilization of purified nuclei with sodium tetrathionate and differs significantly from that obtained by exposing nuclei to 37°C in vitro, unlike to that what previous reports have indicated. 相似文献
65.
Amicucci Antonella Rossi Ismaela Potenza Lucia Agostini Deborah Stocchi Vilberto 《Biotechnology Techniques》1997,11(3):149-154
Isolates of white truffles were identified as Tuber magnatum Pico species using a pair of primers selected from a sequence characterised amplified region (SCAR) and a specific random amplified polymorphic DNA (RAPD) marker. The present study reveals that PCR-fragment-pattern polymorphisms, the construction of probes and couples of primers from one or more of these polymorphic fragments may provide a useful and rapid tool for identifying species of ectomycorrhizal fungi in addition to conventional methods (morphological parameters). 相似文献
66.
67.
M. Es-souni Routhier P. Bournot L. C. Ramirez 《The Journal of steroid biochemistry and molecular biology》1995,52(6):581-585
The Y-1 adrenal cell line was shown to produce 20-dihydroaldosterone from deoxycorticosterone. This compound was identified by GC-MS by comparison with the previously synthesized reference compound. Two other 18-hydroxylated metabolites were identified as 11β,18-dihydroxy-20-dihydroprogesterone from endogenous cholesterol and 18-hydroxy-20-dihydro-11-dehydrocorti-costerone from DOC. The conditions necessary for the synthesis of these compounds are culturing in 20% serum-supplemented medium and repeated incubations with the substrate. The production of 11β-hydroxylated steroids and that of 18-oxygenated steroids is stimulated differently by ACTH and angiotensin II suggesting the expression of two different enzymes, cytochrome P-45011β and cytochrome P-450aldo The Y-1 cell line can secrete either 11β-hydroxylated steroids characteristic of the glucocorticoid pathway or 18-oxygenated steroids characteristic of the mineralocorticoid pathway, which in vivo are generally produced in two different zones of the adrenal cortex. This cell line should be an interesting model for the study of the molecular mechanisms regulating the expression of these two enzymes involved in the final steps of the steroidogenic pathways. 相似文献
68.
F Ramirez S I Tu P R Chatterji B McKeever J F Marecek 《Archives of biochemistry and biophysics》1984,230(1):61-68
The reaction of fluorescamine with ammonia, benzylamine, o,p-dimethylbenzylamine, 2-phenylethylamine, p-aminobenzoic acid, and the mycosamine-containing macrolide antibiotic, amphotericin B, yield compounds which induce significant effects on mitochondrial activities. From their effects on energy-yielding processes which lead to transmembranous proton movements, the compounds may be divided into three classes. While all modifiers significantly inhibit proton movement induced by both ATP hydrolysis and electron transfer in mitochondria, their influence on the primary energy yielding steps are quite different. Class I modifiers, e.g., the compound made from amphotericin B, inhibit electron transfer but have no effect on the Pi release associated with ATP hydrolysis. Class II modifiers, e.g., the compound made from benzylamine, inhibit respiration but stimulate Pi release. Class III modifiers, e.g., the compound made from p-aminobenzoic acid, on the other hand, only slightly increase Pi release but have no effect on redox reactions. These and other effects of the modifiers are taken to mean that the proton movements and their associated energy-yielding processes are only linked indirectly. The effects of the modifiers on State 3 mitochondrial activities were also investigated. Although all the modifiers decrease the rates of both State 3 respiration and its coupled ATP synthesis, the efficiency of energy conversion measured by the P/O ratio remains unaltered. 相似文献
69.
V Pesce Delfino A De Lucia V Scattarella T Lettini R Lenoci V Mitolo 《Bollettino della Società italiana di biologia sperimentale》1984,60(7):1301-1307
An analytical morphometrical investigation of fronto facial profile of Plesianthropus transvaalensis was carried out by means of Fourier spectral series. Amplitude of contributors was evaluated in comparison with harmonic sets of a modern skull and two "mosaics" obtained by a convenient merging of segments of modern and hominid skull profiles. Patterns are distinctly different in Plesianthropus and modern profile because amplitude of second harmonic is greater than first in the former and viceversa in the latter; moreover while in Plesianthropus first and second harmonic give the same phase, it does not occur for modern skull. Fourier series of "mosaic" obtained by frontal profile of Plesianthropus and facial profile of modern resembles the set of modern skull while "mosaic" of modern frontal profile and hominid facial one resembles closely pattern of Plesianthropus. 相似文献
70.
Lipid composition of brain myelin from normal and hyperphenylalaninemic chick embryos 总被引:1,自引:0,他引:1
M J Alejandre C Marco H Ramirez J L Segovia E Garcia-Peregrin 《Comparative biochemistry and physiology. B, Comparative biochemistry》1984,77(2):329-332
The influence of hyperphenylalaninemia on the lipid composition of brain myelin has been investigated in 19-day-old chick embryos. CNP-ase activity was used as myelin marker enzyme for myelin isolation. CNP-ase activity was significantly lower in hyperphenylalaninemic myelin when compared with control. No significant differences were observed after experimental treatment in the total lipid content of myelin as well as in the proportion of cholesterol:phospholipid:galactolipid. Nevertheless, a clear increase in the percentage of esterified cholesterol was found. No appreciable alterations were observed in the phospholipid composition of brain myelin from both control and hyperphenylalaninemic chick embryos. However, the ratio of unsaturated to saturated fatty acids in serine plasmalogen and sphingomyelin was considerably increased by this treatment. This ratio in choline and ethanolamine phosphatides from treated embryos did not differ from that of controls. 相似文献