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1.
PF9601N, N-(2-propynyl)-2-(5-benzyloxy-indolyl) methylamine, an monoamine oxidase (MAO) B inhibitor, has shown neuroprotective properties against dopaminergic toxins. To elucidate the mechanisms involved in this protection, the effect of PF9601N on mitochondria was assessed. PF9601N prevents mitochondrial swelling, drop in the electrical potential and oxidation of sulfhydryl groups, glutathione and pyridine nucleotides induced by Ca2+. These observations demonstrate the protective effect of PF9601N on the induction of mitochondrial permeability transition. This protection is due to the interaction of the secondary protonated amino group in the molecule with pore-forming structures and to its antioxidant property, rather than to inhibition of MAO B activity. PF9601N also prevents the release of cytochrome c from mitochondria, suggesting its potential inhibitory effect on mitochondria-mediated apoptosis. The low IC50 value for this inhibition, in comparison with deprenyl, make it a more efficient compound than propargylamines and other amines in protecting the bioenergetic functions of mitochondria. Received 9 March 2006; received after revision 10 April 2006; accepted 21 April 2006  相似文献   

2.
We examined levels of melatonin in the pineal, eyes and plasma over a 24 h period during development in the altricial zebra finch. Beginning as early as 2 days after hatching there was a distinct 24 h rhythm in melatonin in the pineal and plasma. Beginning at day seven after hatching there was also a 24 h rhythm present in the eyes. In the pineal and eyes the amplitude of the 24 h rhythm increased with age. In contrast, the amplitude of the plasma melatonin rhythm at 2 days was already within the range of adults and did not increase with age. These results confirm and expand earlier findings in the European starling and parallel those from precocial birds indicating that the circadian system is already competent at or shortly after hatching even in atricial birds.  相似文献   

3.
Trefoil factors (TFFs) promote epithelial cell migration to reseal superficial wounds after mucosal injury, but their receptors and the molecular mechanisms underlying this process are poorly understood. In this study, we showed that frog TFF2 activates protease-activated receptor (PAR) 1 to induce human platelet aggregation. Based on this result, we further tested the involvement of PARs in human TFF2 (hTFF2)-promoted mucosal healing. hTFF2-stimulated migration of epithelial HT-29 cells was largely inhibited by PAR4 depletion with small interfering RNAs but not by PAR1 or PAR2 depletion. The PAR4-negative epithelial cell lines AGS and LoVo were highly responsive to hTFF2 as assessed by phosphorylation of ERK1/2 and cell migration upon PAR4 expression. Our findings suggest that hTFF2 promotes cell migration via PAR4. These findings will be helpful in further investigations into the functions and molecular mechanisms of TFFs and PARs in physiology and disease.  相似文献   

4.
Summary The genotype difference (dystrophic vs nondystrophic) in the LDH isozymes is observed in kidney. These differences are evident only at birth and at early developmental stages (before the expression of dystrophic symptoms). The tissue specific genotype differences for PK are limited to the thigh muscle (M form) and heart (L form), after the onset of the condition. These differences may reflect the pleiotropic effect of the dy2J locus during the temporal regulation of these and other enzymes implicated in muscular dystrophy (MD).This research was financed by a Natural Sciences and Engineering Research Council Canada grant to S.M.S.  相似文献   

5.
Summary 2 dietary fats, namely, hydrogenated coconut oil and safflower seed oil were fed at 20% levels to weanling male albino rats for a period of 2 months after which the animals were sacrificed and oxidative phosphorylation measured in liver mitochondria. This ratio was more in the unsaturated-fat-fed group of rats compared to the saturated-fed ones for glutamate and malate; in the case of succinate no such change was noticed.  相似文献   

6.
J Cambar  P Gendre 《Experientia》1978,34(3):371-372
A fine quantitative evaluation of ferritin aggregates in rat GBM permits to counts 5.08 +/- 1.51 and 18.30 +/- 3.21 g/cm2, respectively 30 and 60 min after ferritin injection; likewise, 30 min after ferritin administration, 5.08 +/- 1.51 and 17.11 +/- 3.9 g/cm2, respectively in normal and theophylline-treated animals.  相似文献   

7.
Imazalil is a new fungicide effective against Penicillium molds on fruits after harvest. This compound inhibits ergosterol biosynthesis in mycelia of Penicillium expansum. The accumulation of 24--methylenedithydrolanosterol, obtusifoliol and 14 alpha-methyl-delta 8, 24(28)-ergostadienol in treated fungi suggests that imazalil blocks sterol C--14 demethylation.  相似文献   

8.
Following a serotonin injection, a rise of exocytosis in the sinus gland of the crayfish Astacus leptodactylus is observed together with an increase of the glucose level in the hemolymph. The phenomenon of exocytosis reaches a peak between 2 and 4 h after injection, wheras the highest glucose level in the hemolymph appears between 4 and 6 h after the same injection.  相似文献   

9.
用原位聚合法制备了Sr0.7La0.15Ce0.15Fe11.7Zn0.3O19铁氧体/聚苯胺(PAn)复合材料。采用X射线衍射(XRD)、扫描电子显微镜(SEM)对样品的结构、微观表面形貌和粒子大小进行了表征,用微波矢量网络分析仪测量样品在2~12.4GHZ频率范围内复介电常数和复磁导率,根据测量数据计算微波反射率R与频率f的关系。研究结果表明:PAn包覆于掺杂锶铁氧体表面,PAn/Sr0.7La0.15Ce0.15Fe11.7Zn0.3O19复合材料具有良好的吸波性能,随着掺杂锶铁氧体含量的增加,微波吸收匹配厚度和吸收带宽发生变化:当Sr0.7La0.15Ce0.15Fe11.7Zn0.3O19聚合质量比为40%时,最佳匹配厚度为2.6mm,吸收峰值接近-40dB,峰值频率高于12.4GHz,大于10dB吸收带宽预计达到55GHz。  相似文献   

10.
Poly(ADP-ribose) (PAR) has been identified as a DNA damage-inducible cell death signal upstream of apoptosis-inducing factor (AIF). PAR causes the translocation of AIF from mitochondria to the nucleus and triggers cell death. In living cells, PAR molecules are subject to dynamic changes pending on internal and external stress factors. Using RNA interference (RNAi), we determined the roles of poly(ADP-ribose) polymerases-1 and -2 (PARP-1, PARP-2) and poly(ADP-ribose) glycohydrolase (PARG), the key enzymes configuring PAR molecules, in cell death induced by an alkylating agent. We found that PARP-1, but not PARP-2 and PARG, contributed to alkylation-induced cell death. Likewise, AIF translocation was only affected by PARP-1. PARP-1 seems to play a major role configuring PAR as a death signal involving AIF translocation regardless of the death pathway involved. Received 7 November 2007; received after revision 19 December 2007; accepted 21 December 2007 O. Cohausz, C. Blenn: These two authors contributed equally to this work.  相似文献   

11.
Acetyl-coenzyme A synthetase (AMP forming)   总被引:1,自引:0,他引:1  
Acetyl-coenzyme A synthetase (AMP forming; Acs) is an enzyme whose activity is central to the metabolism of prokaryotic and eukaryotic cells. The physiological role of this enzyme is to activate acetate to acetyl-coenzyme A (Ac-CoA). The importance of Acs has been recognized for decades, since it provides the cell the two-carbon metabolite used in many anabolic and energy generation processes. In the last decade researchers have learned how carefully the cell monitors the synthesis and activity of this enzyme. In eukaryotes and prokaryotes, complex regulatory systems control acs gene expression as a function carbon flux, with a second layer of regulation exerted posttranslationally by the NAD+/sirtuin-dependent protein acetylation/deacetylation system. Recent structural work provides snapshots of the dramatic conformational changes Acs undergoes during catalysis. Future work on the regulation of acs gene expression will expand our understanding of metabolic integration, while structure/function studies will reveal more details of the function of this splendid molecular machine.Received 4 December 2003; received after revision 2 March 2004; accepted 16 March 2004  相似文献   

12.
Zusammenfassung Die- Rezeptoren vom Sphinkter von Oddi werden durch Terbutalin selektiv stimuliert.  相似文献   

13.
Two experiments have been carried out to verify the effect of ethylene on the primary attraction ofPhloeotribus scarabaeoides under both laboratory and field conditions. The experiments were based on the enhancement of ethylene production by olive branches and trunks after the application of (2-chloroethyl)phosphonic acid. Under laboratory conditions, the beetles' response was strongly stimulated on the treated branches. Under field conditions, the treatment aided the location of the olive wood by the flying beetles, and the attack density was significantly greater in the treated wood at the end of the experiment.  相似文献   

14.
Summary Somatic chromosome complements of the Indian burrowing toad,Uperodon globulosum, have been described for the first time. The 2n number is 26 (NF=52) in both the sexes. No heteromorphism in relation to sex chromosome pair has been recorded. Deviations from 2n number (2n=10–28) have been noticed in the cells of different specimens. The result has been compared withU. systoma.Acknowledgment. Sincere thanks are due to Prof. P. K. Ghosh, Hooghly Mohsin College and to Dr A. K. Roy of the same college for encouragement. Thanks are due to Mr Bipul Kumar Das for his help during collection of specimen.  相似文献   

15.
Summary The synthesis of the nonapeptide2, corresponding to the formula of the (Glu-OMe)2-litorin, is described. The compound has the same chemical and biological properties of the second bombesin-like peptide extracted from the skin of the Australian frog Litoria aurea.  相似文献   

16.
Corticotropin-releasing factor (CRF), also termed corticotropin-releasing hormone (CRH) or corticoliberin, is the major regulator of the adaptive response to internal or external stresses. An essential component of the adaptation mechanism is the adrenal gland. CRF regulates adrenal function indirectly through the central nervous system (CNS) via the hypothalamic-pituitary-adrenal (HPA) axis and via the autonomic nervous system by way of locus coeruleus (LC) in the brain stem. Accumulating evidence suggests that CRF and its related peptides also affect the adrenals directly, i.e. not through the CNS but from within the adrenal gland where they form paracrine regulatory loops. Indeed, CRF and its related peptides, the urocortins (UCNs: UCN1, UCN2 and UCN3), their receptors CRF type 1 (CRF1) and 2 (CRF2) as well as the endogenous pseudo-receptor CRF-binding protein (CRF-BP) are all expressed in adrenal cortical, medullary chromaffin and resident immune cells. The intra-adrenal CRF-based regulatory system is complex and depends on the balance between the local concentration of CRF ligands and the availability of their receptors. Received 19 December 2006; received after revision 20 February 2007; accepted 26 March 2007  相似文献   

17.
Summary In experiments of infusion made on guineapigs, Dichlorisoproterenol was injected after the appearance of the first symptoms of toxicity in the ECG. It reduced the toxicity of convallatoxol, g-strophanthin and lanatosid C, but it was not quite effective against digoxin and digitoxin.

Über einen Teil der Befunde wurde auf dem 2. Internationalen Pharmakologenkongress in Prag berichtet (Förster undSziegoleit).  相似文献   

18.
The synthesis of azomycin (2-Nitroimidazole)   总被引:1,自引:0,他引:1  
Riassunto La sintesi del 2-nitroimidazolo e del 1-metil-2-nitroimidazolo per diazotasione e reasione di Gattermann a partire dai corrispondenti 2-aminoimidasoli dimostra che, in determinate condizioni, questi ultimi si comportano come composti a carattere aromatico.  相似文献   

19.
Summary Tryptophan, 5-HT, MAO and 5-HIAA were determined in the first 5 segments of earthworms (Oligochaetae) where the brain and subesophagic ganglions are located. Tranylcypromine (IMAO) decreased MAO activity increasing 5-HT and decreasing 5-HIAA. Motility and survival of worms were disturbed. InAllolobophora species (young worms), parathion fumigation decreased acetylcholinesterase (AChE) activity and increased Trp, 5-HT and 5-HIAA. Motility was diminished after 24 h: it worsened after 72, but returned to normal levels 40/50 days later.Publication of the National Institute of Agrarian Technology (INTA), Argentina.Acknowledgments. We are most grateful to Prof. Zlatko Tomsic (from the Lillo Institute, Tucumán) and to Leticia Alvarado (from INTA) and to Prof. Mirta P. de Matosian for earthworm classification.  相似文献   

20.
Summary Larval brain mitotic karyotype ofAn. indefinitus from Kanchanaburi exhibits a supernumerary (B) chromosome which is apparently common in that population. 1 or 2 B-chromosomes have been observed in the samples from 5 isofemale lines examined.Acknowledgments. We thank K. Mongkolpanya and P. Kittayarak for species identification. Part of this work was supported by Mahidol University Research Fund and AFRIMS.  相似文献   

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