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1.
Prostaglandins A2, E1, E2, methylated E2s and F2α affected erythropoiesis and/or erythropoietin (Ep) production. This action is indicated in the exhypoxic, polycythemic mouse where radioiron incorporations into RBC increased after administration of these compounds. The kidney and liver have been indicated through previous studies, to actively participate in Ep production. By the removal of one of these active sites in a murine system treated with prostaglandins it is shown that a response is reflected in Ep levels. Interference of the action of prostaglandins (PG) is altered by the removal of one of these target sites of Ep production. The erythropoietic responses elicited by PGA2, E1, and perhaps the methylated PGE2s act through the liver whereas PGE2 may operate through a renal pathway for its response. PGF reveals no effect on erythropoietic activity and is no different than that observed for vehicle-treated controls. The prostaglandins tested appear to act primarily through the kidney or liver but the possibility exists that some yet undetermined organ site may also be involved.  相似文献   

2.
Saponification of the bis(carbamic acid ester) 1,3-C6H4(CMe2NHCO2Me)2 (1), made by the addition of methanol to commercial 1,3-C6H4(CMe2NCO)2, yielded the meta-phenylene-based bis(tertiary carbinamine) 1,3-C6H4(CMe2NH2)2 (2). Dinuclear [{(η4-1,5-C8H12)RhCl}2{μ-1,3-C6H4(CMe2NH2)2}] (3) resulted from the action of 2 on [{(η4-1,5-C8H12)Rh(μ-Cl)}2] in toluene. Combination of 2 with PdCl2 or K2[PdCl4] gave the dipalladium macrocycle trans,trans-[{μ-1,3-C6H4(CMe2NH2)2}2(PdCl2)2] (4) along with cyclometalated [{2,6-C6H3(CMe2NH2)2NC1N′}PdCl] (5). Substitution of PEt3 for the labile chlorido ligand of 5 afforded [{2,6-C6H3(CMe2NH2)2NC1, κN′}Pd(PEt3)]Cl (6). The crystal structures of the following compounds were determined: bis(carbamic acid ester) 1, ligand 2 as its bis(trifluoroacetate) salt [1,3-C6H4(CMe2NH3)2](O2CCF3)2, 2 · (HAcf)2, complexes 3 and 6, as well as 1,3-C6H4(CMe2OH)2 (the diol analogue of 2).  相似文献   

3.
The following experiments were designed in order to examine the inter-relationships of various prostaglandins (PG's) and the adrenergic nervous system, in conjunction with blood pressure and heart rate responses, in vivo. Stimulation of the entire spinal cord (50v, 0.3–3 Hz, 1.0 msec) of the pithed rat increased blood pressure, heart rate and plasma epinephrine (EPI) and norepinephrine (NE) concentration (radioenzymatic-thin layer chromatographic assay). Infusion of PGE2(10–30 μg/kg. min, i.v.) suppressed blood pressure and heart rate responses to spinal cord stimulation while plasma EPI (but not NE) was augmented over levels found in control animals. PGI2 (0.03–3.0 μg/kg. min, i.v.) suppressed the blood pressure response to spinal cord stimulation without any effect on heart rate or the plasma catecholamine levels. PGE2 and PGF2α(10–30 μg/kg. min, i.v.) did not change the blood pressure, heart rate or plasma EPI and NE responses to the spinal cord stimulation although PGF2α disclosed an overall vasopressor effect during the pre-stimulation period. At the pre-stimulation period it was also observed that PGE2, PGF2α and PGI2, had a positive chronotropic effect on the heart rate, the cardiac accelerating effect of PGE2 was not abolished by propanolol. These in vivo studies suggest that in the rat, PGE2 and PGI2 modulate sympathetic responses, primarily by interaction with the post-synaptic elements — PGE2 on both blood vessels and the heart and PGI2 by acting principally on blood vessels.  相似文献   

4.
Treatment of the six-coordinate trimethylstannyl complex, Os(SnMe3)(κ2-S2CNMe2)(CO)(PPh3)2 (1) with SnMe2Cl2 produces Os(SnMe2Cl)(κ2-S2CNMe2)(CO)(PPh3)2 (2), which in turn reacts readily with hydroxide ion to give, Os(SnMe2OH)(κ2-S2CNMe2)(CO)(PPh3)2 (3). The osmastannol complex 3 undergoes a reaction with 2 equivalents of tBuLi, in which one of the phenyl rings of a triphenylphosphine ligand is “ortho-stannylated”, without cleavage of the Os-Sn bond, to give the cyclic complex, Os(κ2(Sn,P)-SnMe2C6H4PPh2)(κ2-S2CNMe2)(CO)(PPh3) (4). This novel cyclic complex is selectively functionalised at the tin atom by reaction with SnMe2Cl2 which exchanges one methyl group for chloride giving the diastereomeric mixture, Os(κ2(Sn,P)-SnMeClC6H4PPh2)(κ2-S2CNMe2)(CO)(PPh3) (5a/5b). Crystal structure determination reveals that both diastereomers occur in the unit cell. The mixture, 5a/5b, undergoes reaction with hydroxide ion to give the diastereomeric osmastannol complexes, Os(κ2(Sn,P)-SnMeOHC6H4PPh2)(κ2-S2CNMe2)(CO)(PPh3) (6a/6b) and with sodium borohydride to give the corresponding tin-hydride mixture, Os(κ2(Sn,P)-SnMeHC6H4PPh2)(κ2-S2CNMe2)(CO)(PPh3) (7a/7b). Crystal structure determinations for 2, 4, and 5a/5b have been obtained.  相似文献   

5.
Reactions of orthometallated binuclear palladium complexes with NaER, obtained by NaBH4 reduction of R2E2 in methanol, gave complexes, [Pd2(μ-ER)2(CY)2] (HCY = N,N-dimethylbenzylamine (C6H5CH2NMe2), N,N-dimethylnaphthylamine (C10H7NMe2), tri-o-tolylphosphine {P(tol-o)3}; ER=SePh, SeMes, TePh, TeMes (Mes = 2,4,6-Me3C6H2). Similar reactions of [Pd2(μ-Cl)2(C10H6NMe2-C,N)2] with Pb(SMes)2 or MesSH in the presence of NaHCO3 gave chloro/thiolato-bridged complex [Pd2(μ-Cl)(μ-SMes)(C10H6NMe2-C,N)2]. The newly synthesized complexes were characterized by elemental analysis, UV-Vis, IR, NMR (1H, 13C, 31P, 77Se, 125Te) spectroscopy. These complexes crystallized out preferentially in sym-cis configuration. A low energy charge transfer transition has been identified from chalcogenolate centers to an emptyπ orbital of cyclometallated ligand in absorption spectroscopy in these complexes. The structures of [Pd2(μ-Cl)(μ-SMes)(C10H6NMe2-C,N)2] (1) and [Pd2(μ-SePh)2(C10H6NMe2-C,N) 2] (3) have been established by single crystal X-ray diffraction analyses. In the former, the two palladium atoms are held together by chloro and thiolato bridges whereas in the latter, the two phenylselenolato ligands bridge two palladium atoms. The pyrolysis of [Pd(μ-TeMes)(C10H6NMe2-C,N)]2 (10) in a furnace gave Pd7Te3 whereas thermolysis in TOPO afforded primarily PdTe2.  相似文献   

6.
The heme iron of the β chains of mammalian hemoglobins are rapidly and selectively oxidized in the presence of excess Cu(II) ions in a reaction that requires the presence of a free -SH groups on the β globin chain. The presence of freely reactive -SH groups on the α chains of cat and sheep hemoglobins does not alter the course of this reaction: only the β hemes are oxidized rapidly by Cu(II) in these hemoglobins. Two equivalents of copper are required for the rapid oxidation of the two β chain hemes per mole of cat hemoglobin, in contrast with the four equivalents that are required for reaction with human hemoglobin. The human-cat hybrid hemoglobins, α2Humanβ2Cat and α2Catβ2Human, required two and four equivalents of copper/mol, respectively, for the reaction. Thus, the kinetics and stoichimetry of the reaction are determined by the nature of the β subunit. Analysis of the esr spectra of the products of the reaction of Cu(II) with these hemoglobins indicate that human hemoglobin and the hybrid α2Catβ2Human contain tight binding sites for two equivalents of Cu(II) that are not involved in the oxidation reaction and are not present in cat hemoglobin or α2Humanβ2Cat. Cat β globin like others (sheep, bovine) that lack the tight binding site, has no histidine residue at 2β. It has phenylalanine in this position. These results support the suggestion of Rifkind et al. (Biochemistry 15,5337[1976]) that the tight binding site is near the amino terminal region of the β chain and is associated with histidine 2β.  相似文献   

7.
Berberine (BBR), an isoquinoline derivative alkaloid isolated from Chinese herbs, has a long history of uses for the treatment of multiple diseases, including cancers. However, the precise mechanisms of actions of BBR in human lung cancer cells remain unclear. In this study, we investigated the molecular mechanisms by which BBR inhibits cell growth in human non-small-cell lung cancer (NSCLC) cells. Treatment with BBR promoted cell morphology change, inhibited cell migration, proliferation and colony formation, and induced cell apoptosis. Further molecular mechanism study showed that BBR simultaneously targeted multiple cell signaling pathways to inhibit NSCLC cell growth. Treatment with BBR inhibited AP-2α and AP-2β expression and abrogated their binding on hTERT promoters, thereby inhibiting hTERT expression. Knockdown of AP-2α and AP-2β by siRNA considerably augmented the BBR-mediated inhibition of cell growth. BBR also suppressed the nuclear translocation of p50/p65 NF-κB proteins and their binding to COX-2 promoter, causing inhibition of COX-2. BBR also downregulated HIF-1α and VEGF expression and inhibited Akt and ERK phosphorylation. Knockdown of HIF-1α by siRNA considerably augmented the BBR-mediated inhibition of cell growth. Moreover, BBR treatment triggered cytochrome-c release from mitochondrial inter-membrane space into cytosol, promoted cleavage of caspase and PARP, and affected expression of BAX and Bcl-2, thereby activating apoptotic pathway. Taken together, these results demonstrated that BBR inhibited NSCLC cell growth by simultaneously targeting AP-2/hTERT, NF-κB/COX-2, HIF-1α/VEGF, PI3K/AKT, Raf/MEK/ERK and cytochrome-c/caspase signaling pathways. Our findings provide new insights into understanding the anticancer mechanisms of BBR in human lung cancer therapy.  相似文献   

8.
Measurement of isotope ratios in 1α,2α,3β-trihydroxy-p-menthane, which has been biosynthesized in Fusicoccum amygdali from 3H- and 14C-labelled mevalonate and in its degradation product diosphenol indicates that: (a) four tritium atoms arising from [5-3H2, 2-14C]MVA are retained, one more than suggested from the hydroxylation pattern, (b) menth-2-ene-1-ol is generated from an α-terpinyl cation through a 1,3-hydride shift and (c) trans-cleavage of an α-epoxide by hydrolysis gives 1α,2α,3β-trihydroxy-p-menthane.  相似文献   

9.
The dicarbonyl and diphosphine complexes of the type (η5-C5H5)Fe(L)2ER3 (L2 = (CO)2 (a), (Ph2P)2CH2 (b); ER3 = CH3 (1a/b); SiMe3 (2a/b), GeMe3 (3a/b), SnMe3 (4a/b)) were synthesized and studied electrochemically. Cyclic voltammetric studies on the dicarbonyl complexes 1a-4a revealed one electron irreversible oxidation processes whereas the same processes for the chelating phosphine series 1b-4b were reversible. The Eox values found for the series 1a-4a were in the narrow range 1.3-1.5 V and in the order Si > Sn ≈ Ge > C; those for 1b-4b (involving replacement of the excellent retrodative π-accepting CO ligands by the superior σ-donor and poorer π-accepting phosphines) have much lower oxidation potentials in the sequence Sn > Si ≈ Ge > C. This latter oxidation potential pattern relates directly to the solution 31P NMR chemical shift data illustrating that stronger donation lowers the Eox for the complexes; however, simple understanding of the trend must await the results of a current DFT analysis of the systems.  相似文献   

10.
A new molecular loop composed of two quadruply bonded Mo2(DAniF)2 units (DAniF=N,N-di-p-anisylformamidinate) linked by two chiral allene-1,3-dicarboxylate anions has been prepared from the reaction of [cis-Mo2(DAniF)2(MeCN)4](BF4)2 with the bis(tetraethylammonium) salt of allene-1,3-dicarboxylic acid. This compound, [cis-Mo2(DAniF)2]2(O2C-CHCCH-CO2)2 (1), has been characterized by X-ray crystallography and by 1H NMR and UV-Vis spectroscopy. The molecule possesses a center of inversion and hence is meso. There is only weak electronic coupling between the two Mo2 4+ units as revealed by electrochemical measurements.  相似文献   

11.
潘庆民1,于振文2,王月福2   总被引:5,自引:0,他引:5  
采用盆栽和水泥池栽研究了追氮时期对小麦光合作用、14C同化物运转分配和硝酸还原酶(NR)活性的影响.结果表明,拔节(雌雄蕊原基形成)期较起身(二棱)期追施氮肥,显著提高了小麦开花后的旗叶叶绿素含量和单叶光合速率;灌浆期旗叶14C同化物向籽粒转移比例显著提高,而在营养器官的滞留比例显著降低;旗叶和根系中硝酸还原酶(NR)活性亦显著提高.小麦穗粒数、粒重和产量增加,蛋白质含量提高.  相似文献   

12.
N-2′-Acetoxybenzoyl (aspirin) derivatives (degree of substitution 0·35–1·00) of chitosan, N-desulphated heparin and 2-amino-2-deoxy-d-glucose were prepared by methods that gave yields in the range 65–86%. The salicylate of chitosan was isolated with a 98% yeild. Aspirin or salicylic acid was released much more slowly from N-(2′-acetoxybenzoyl)-chitosan than from the salicylate of chitosan, and much faster at 37°C in 0·1 m NaOH solution than in 2% aqueous acetic acid solution. Salicylic acid was isolated from the dialysate (0·1 m NaOH solution) of N-(2′-acetoxybenzoyl)-chitosan.  相似文献   

13.
1. The 5-HT2 receptors subdivision into the 5-HT2A/2B/2C subtypes along with the advent of the selective antagonists has allowed a more detailed investigation on the role and therapeutic significance of these subtypes in cognitive functions. The present study further analyzed the 5-HT2 receptors role on memory consolidation.2. The SB-200646 (a selective 5-HT2B/2C receptor antagonist) and LY215840 (a nonselective 5-HT2/7 receptor antagonist) posttraining administration had no effect on an autoshaped memory consolidation. However, both drugs significantly and differentially antagonized the memory impairments induced by 1-(3-chlorophenyl)piperazine (mCPP), 1-naphtyl-piperazine (1-NP), mesulergine, or N-(3-trifluoromethylphenyl) piperazine (TFMPP).3. In contrast, SB-200646 failed to modify the facilitatory procognitive effect produced by (±)-2,5-dimethoxy-4-iodoamphetamine (DOI) or ketanserin, which were sensitive to MDL100907 (a selective 5-HT2A receptor antagonist) and to a LY215840 high dose.4. Finally, SB-200646 reversed the learning deficit induced by dizocilpine, but not that by scopolamine; while SB-200646 and MDL100907 coadministration reversed memory deficits induced by both drugs.5. It is suggested that 5-HT2B/2C receptors might be involved on memory formation probably mediating a suppressive or constraining action. Whether the drug-induced memory impairments in this study are explained by simple agonism, antagonism, or inverse agonism at 5-HT2 receptors remains unclear at this time.6. Notably, the 5-HT2 receptor subtypes blockade may provide some benefit to reverse poor memory consolidation conditions associated with decreased cholinergic, glutamatergic, and/or serotonergic neurotransmission.  相似文献   

14.
Prostaglandin (PG) D2 was biosynthesized by rabbit renal papillae incubates in vitro. Quantification of the renal prostaglandins by gas chromatography-mass spectroscopy demonstrated that the concentration of PGD2 generated by renal papillae was to the amount of PGE2 or about 1 μg/g tissue/30 min. Infusion of the sodium salt of PGD2 into the renal artery of the dog produced a dose related increase in renal blood flow and urine flow, free water clearance, sodium excretion and potassium excretion without changes in systemic hemodynamics. At low doses PGD2 increased renal blood flow to all cortical zones. Higher concentrations of PGD2 produced a shift in the intrarenal distribution of blood flow toward the juxtamedullary nephrons.  相似文献   

15.
Reaction of Cu(NO3)2 · 3H2O, N,N,N′,N′-tetramethyl-ethylenediamine (L) and sodium dicyanamide (Nadca) in aqueous medium yields a complex the {[Cu2L2(μ-1,5-dca)2(dca)2]}n complex, 1. Single crystal X-ray analysis reveals that complex 1 has a 1D infinite chain structure in which copper(II) ions are bridged by single dicyanamide anions in an end-to-end fashion. The coordination environment around copper(II) is distorted square pyramidal. Two among the four coordination sites of the basal plane are occupied by the nitrogen atoms of the diamine and two remaining sites are occupied by the terminal nitrogen atom of a bridging and of a monodentate dca anions. The fifth coordination site (apical) is occupied by a nitrogen atom from a bridging dca anion of an adjacent CuL(dca)2 moiety, yielding the [Cu2L2(μ-1,5-dca)2(dca)2] dinuclear unit. Dimeric units are connected to each other by single μ-1,5-dicyanamido group to form infinite 1D chains which propagate parallel to the crystallographic c-axis. The variable temperature magnetic susceptibility measurements evidenced weakly antiferromagnetic interactions (J = −0.26 cm−1) in {[Cu2L2(μ-1,5-dca)2(dca)2]}n, 1.  相似文献   

16.
A new HgII coordination polymer with 4,4′-bipyridine and acetate anions, [Hg(μ-4,4′-bipy)(μ-AcO)(AcO)]n · n/2H2O (1), has been synthesized, characterized by elemental analysis, IR-, 1H NMR-, 13C NMR spectroscopy and its structure determined by single-crystal X-ray diffraction. The thermal stability of compound 1 was studied by thermal gravimetric (TG) and differential thermal analyses (DTA). The structural studies of compound 1 show that the structure may be considered as a coordination polymer of mercury(II) consisting of linear double chains formed by a bridging 4,4′-bipy ligand and by connecting acetate-bridged centrosymmetric {Hg2(OAc)2}2+ nodes. Solid-state luminescent spectra of the ligand 4,4′-bipyridine and compound 1 indicate a fluorescent broad emission band with the maximum intensity at ca 468.2 and 446.4 nm upon excitation at 295 nm, respectively. The stability of porous network after removal of guest water molecules is not confirmed by X-ray powder diffraction.  相似文献   

17.
Prostacyclin (PGI2), prostaglandin E2 (PGE2) and prostaglandin F2∝ (PGF2∝) were tested here in unanesthetized male Sprague-Dawley rats for their effects on the cardiovascular system as mediated by the Central nervous system. Cannulae were chronically implanted into the third cerebral ventricle, femoral arteries and femoral veins of rats. Both PGE2 and PGF2∝ induced increased arterial blood pressure and tachycardia by an action on the central nervous system. The changes seen with PGE2 were larger than those observed with PGF2∝. Only transient depressor effects were seen with PGI2 and these changes appeared to be due to the leakage of the substance into the peripheral vascular system.  相似文献   

18.
Cardiotoxicity is a severe considerable side effect of cisplatin (CDDP) that requires much medical attention. The current study investigates the cardioprotective effects of canagliflozin (CA) against CDDP-induced heart toxicity. Rats were allocated to the control group; the CA group was administered CA 10 mg/kg/day orally for 10 days; the CDDP group was injected with 7 mg/kg, intraperitoneal as a single dose on the 5th day, and the CDDP + CA group. Compared to the CDDP-treated group, CA effectively attenuated CDDP-induced heart injury as evidenced by a decrease of serum aspartate aminotransferase, alkaline phosphatase, creatine kinase-MB, and lactate dehydrogenase enzymes and supported by the alleviation of histopathological changes in cardiac tissues. Biochemically, CA attenuated cardiac oxidative injury through upregulation of the nuclear factor-erythroid 2 related factor 2 (Nrf2) signal. CA suppressed inflammation by decreasing cardiac NO2, MPO, iNOS, nuclear factor kappa B (NF-κB), tumor necrosis factor-alpha, and interleukin 1-beta levels. Besides, CA significantly upregulated cardiac levels of phosphoinositide 3-kinase (PI3K), protein kinase B (AKT), and p-AKT proteins. Moreover, CA remarkably mitigated CDDP-induced apoptosis via modulation of Bax, cytochrome C, and Bcl-2 protein levels. Together, the present study revealed that CA could be a good candidate for preventing CDDP-induced cardiac injury by modulating iNOS/NF-κB, Nrf2, PI3K/AKT, and Bax/cytochrome C/Bcl-2 signals.  相似文献   

19.
酸雨作用下的森林冠层盐基离子(Ca2+,Mg2+,K+)淋洗   总被引:14,自引:1,他引:13  
在韶山针阔叶混交林中设立了10个30 m×30 m的样方,对1年中各个季节的森林截留沉降、降雨后树冠层总滤出量、盐基离子滤出量以及树冠层对H+和NH4+的摄入量进行了分析和估算.韶山森林湿沉降成分中以Ca2+为主,Mg2+,K+含量较低.树冠层盐基离子总滤出量中Ca2+最高,达到155.34 mmo1 m-2a-1,Mg2+最低,为30.74mmol m-2a-1,K+居中,为84.13 mmol m-2a-1.Ca2+的大量滤出表明它是树冠层缓冲降水酸度的主要介质,同时也表明酸雨对韶山森林的潜在危害,其在总滤出量中的比重的季节变化是夏(58.4%)>春(54.1%)>冬(51.4%)>秋(32.5%).盐基离子的滤出量以冬→春→夏→秋依次递减,但是树冠层季节摄入NH4的量在30-100mmo1 m-2而对H+的摄入量则在30-180 mmol m-2.  相似文献   

20.
Summary A 21/2 years old girl with multiple malformations is reported. The cytogenetic and autoradiographic investigations show a trisomy D2(14). In the following symptoms the clinical signs are different from the syndrome of a trisomy D1(13): There are no malformations of the eyes, no inborn deafness, no malformations of the heart and kidneys, no hypoplasia of the thumb. The child does not show any signs of capillary haemangioma and no aplasia of the root of the bony nose. The malformation of the bony pelvis, like a splitted pelvis with very narrow high iliococcygeals is remarkable. The child shows all the mainsymptoms of the other autosomal trisomies: oligophrenia, craniofacial dysmorphia, hypotonia of the muscle tonus and dysplasia of the ears.
Trisomie D2 bei einem 21/2 jährigen Mädchen (47,XX,14+)
Zusammenfassung Es wird über ein 21/2jähriges Mädchen mit multiplen Fehlbildungen berichtet, bei dem die autoradiographische Chromosomenanalyse eine Trisomie D2 ergab. Die klinische Symptomatik des Kindes unterscheidet sich von der einer D1-Trisomie in folgenden Symptomen: Es fehlen die Mißbildungen der Augen, die angeborene Taubheit. Mißbildung des Herzens und der Nieren lassen sich klinisch und röntgenologisch nicht nachweisen. Es besteht keine Polydaktylie, keine Daumenhypoplasie, das Kind weist keine capillären Hämangiome auf und es besteht keine Aplasie der Nasenwurzel. Auffällig sind bei der Patientin die Fehlbildung des knöchernen Beckens im Sinne eines Spaltbeckens mit sehr schmalen, hohen Beckenschaufeln.


Mit Unterstützung durch die Deutsche Forschungsgemeinschaft, AZ Mu 258/3.  相似文献   

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