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1.
The plasma concentrations of two bone matrix proteins (osteocalcin, osteonectin) were monitored in 56 samples from 14 patients receiving renal transplants and the values compared with serum bone alkaline phosphatase mass concentrations and osteotropic hormone levels (parathyroid hormone, calcitriol). There were no significant changes in the concentrations of plasma osteonectin at any time after transplantation, as compared with the values before transplantation (P > 0.1). None of the plasma samples showed osteonectin levels above the reference interval. There was a weak but significant relationship between platelet counts and plasma osteonectin levels (r = +0.322; P < 0.05). Osteocalcin showed a marked decrease of the values 1 week following transplantation as compared with the values before transplantation without further change of the values 1 and 3 months after transplantation (P > 0.5) whereas 3 months after transplantation bone alkaline phosphatase levels were higher than before transplantation (P < 0.05). Multiple regression analysis (performed with data from 42 samples obtained after transplantation) revealed serum creatinine as an independent predictor of plasma osteocalcin whereas serum calcitriol was an independent predictor of serum bone alkaline phosphatase (P < 0.05). No correlation was observed between serum calcitriol/plasma parathyroid hormone on the one hand and plasma osteocalcin on the other (P > 0.05). After transplantation there was a lack of correlation between serum bone alkaline phosphatase mass concentrations and plasma osteocalcin values (P > 0.05). In conclusion, serum bone alkaline phosphatase should be preferred to bone matrix proteins for the assessment of bone metabolism in patients receiving renal transplants: (a) bone alkaline phosphatase-but not osteocalcin-is significantly correlated with calcitriol and adequately reflects increased bone formation after renal transplantation; (b) interpretation of osteocalcin values is severely hampered by their strong correlation with serum creatinine concentrations; (c) plasma osteonectin determinations are not useful for monitoring bone formation.  相似文献   

2.
A series of novel 7-[3-(1-piperidinyl)propoxy]chromenones was synthesized and tested as potential antipsychotics in several in vitro and in vivo assays. The compounds possessed good affinity for D2 receptors, together with a greater affinity for 5-HT2 receptors, a profile which has been proposed as a model for atypical antipsychotics. Several agents also displayed a high potency in the climbing mice assay on oral administration, suggesting a potent antipsychotic effect as compared to reference standards. Compound 23 was selected for further pharmacological evaluation. Induction of catalepsy and inhibition of stereotypies weaker than standards, along with a lower increase in serum prolactin levels, were indicative of a potential atypical profile for this compound. From these results, 7-[3-[4-(6-fluoro-1, 2-benzisoxazol-3-yl)piperidin-1-yl]propoxy]-3-(hydroxymethyl )chromen- 4-one (23, abaperidone) has been proposed for clinical evaluation in humans as a potential atypical antipsychotic.  相似文献   

3.
A series of phenylpiperazinylalkyl moieties were attached to monocyclic or bicyclic substituted pyridazinones and the new compounds tested for their affinity towards alpha1-adrenoceptor and its alpha1a, alpha1b and alpha1d subtypes, as well as serotonin 5-HT1A receptor. Several analogues (5, 6, 9, and 10) showed remarkable potency and selectivity towards alpha1a, and alpha1d with respect to alpha1b subtype. None of the test compounds exhibited significant affinity for 5-HT1A receptor. Finally, on the basis of the alpha1-AR subtypes 3D models recently proposed, we have elaborated theoretical interaction models for the new compounds. The theoretical study allowed us to predict the affinity of the new compounds as well as to infer the structural/dynamics determinants of their interaction with the three alpha1-AR subtypes.  相似文献   

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张秀英  李书静 《稀有金属》2005,29(6):871-874
2,6-吡啶二甲酸钠与三氯化镓在pH≈3的条件下直接反应,合成了NaGa(C7H3NO4)2·2H2O配合物单晶.通过元素分析、红外及X射线衍射分析确定了配合物的结构.以该配合物作为催化剂,用罗丹明B模拟染料废水进行了光催化降解脱色试验,对影响反应的各种条件(如催化剂的投加量,染料的初始浓度,通氧速率及光源)进行了考察.结果表明,在催化剂为20mg,染料初始浓度为2.0×10-4mol·L-1,通氧速率为200ml·min-1,光源为500W汞灯时,配合物NaGa(C7H3NO4)2·2H2O具有优良的催化活性,1h内对罗丹明B的降解率可达98.9%.  相似文献   

7.
The synthesis of two series of derivatives containing the quinazolinone-4 moiety is described. 3-Amino-2(1H)-thioxo-4(3H)-quinazolinone (1) was subjected to reactions with halogenoketones and halogenoaldehydes, leading to the production of the corresponding ketones, aldehydes, Schiff bases, and 6-oxo-1,4,5-thiadiazin[2,3-b]quinazoline derivatives. Subsequently, 1 was condensed with selected alpha, beta-unsaturated carbonyl compounds, aldehydes, ketones, acid chlorides, and esters. The compounds were tested for their potential activity in a model of humoral and cellular immune response. The tests showed that the compounds exhibited differential immunotropic activities. Of particular interest is compound 19, exhibiting a strong stimulatory activity with regard to cellular immune response and compound 16 exerting a strong inhibitory action in both types of the immune response.  相似文献   

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The syntheses and biological evaluations of (23R)- and (23S)-24,24-difluoro-1 alpha,23,25-trithydroxyvitamin D3 (3a and 3b), new C-24 fluorinated analogs of 1 alpha,25-dihydroxyvitamin D3, are described. The syntheses of these compounds were achieved in 3 steps from (5Z,7E,20R)-1 alpha,3 beta-bis-[(tert-butyldimethylsilyl)oxy]-20-formylmethyl-9,10-seco- 5,7,10(19) pregnatriene (5) which is derived from vitamin D2. The absolute configuration at the C-23 position of 3a and 3b was determined by the modified Mosher method. The relative affinities of 3a and 3b to the vitamin D receptor were both 10 and 14 times lower than that of 1 alpha,25-dihydroxyvitamin D3 (1), and to vitamin D binding protein were also both 130 and 40 times lower. The HL-60 cell differentiating activity of 3a was 6 times more potent than that of 1, while there was no remarkable difference in activity between 3b and 1.  相似文献   

10.
The synthesis and SAR of a series of (Z)-(+/-)-1-azabicyclo[2.2. 1]heptan-3-one, O-(3-aryl-2-propynyl)oximes are described. The biochemistry and pharmacology of 24Z (PD 142505) and its enantiomers are highlighted. 24Z is functionally an m1-selective muscarinic agonist. Efficacy and m1 selectivity reside in the R enantiomer, (R)-24Z (CI-1017).  相似文献   

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The lethal effects of 4-(3-(2-chloroethyl)-3-nitrosoureido)-cis-cyclohexanecarboxylic acid (cis-acid), a water-soluble nitrosourea derivative, were investigated on a human lymphoma cell line. The survival of asynchronous cells exposed to increasing concentrations of the drug was characterized by a threshold exponential curve (Do = 20 microgram/ml; Dq = 20 microgram/ml, 1 hour) similar to that of other nitrosourea derivatives. cis-Acid exerted its main killing effect on cells in early S and in late G2 phase. Cells in mid S and early G1 phase were tenfold more resistant. Changes in survival response as a function of cell cycle stage were reflected primarily by changes in the extent of the shoulder region of the survival curve. In contrast to other nitrosoureas, the lethal effectiveness of cis-acid in solution was stable and the drug could sterilize large numbers of cells in short periods of time. Another important major difference observed for cis-acid with respect to classic nitrosourea derivatives was the capacity of treated cells to recover from sublethal and potentially lethal damage. Our studies have shown that cis-acid is as effective in killing cultured human lymphoma cells as other nitrosoureas, but possibly with a mechanism different from that of these compounds. The major shortcoming noted for cis-acid, namely the capacity of treated cells to recover from drug-induced damage, is offset by the relatively long stability of its killing effect. This, and the fact that cis-acid can be administered in an aqueous solution, make this agent an appealing compound for clinical trials.  相似文献   

13.
A series of 4-(omega-(arylalkyloxy)alkyl)-1H-imidazoles and related sulphur-containing compounds have been prepared and evaluated for their histamine H3-autoreceptor antagonist in vitro potency in an assay on synaptosomes of rat cerebral cortex. In addition, the in vivo potency has been determined from the changes in N tau-methylhistamine levels in brain after p.o. administration to mice. Compounds with different alkyl chains and various aryl moities have been synthesized and tested to explore structure-activity relationships. Within this series of novel antagonists, (1H-imid-azol-4-yl)methyl and 2-(1H-imidazol-4-yl)ethyl ether derivatives showed low to moderate H3-receptor antagonist potency, whereas the corresponding allyl and propyl derivatives were compounds with high antagonist in vitro potency. Corresponding thioether or sulphoxide derivatives also showed antagonists activity. Additionally, some ether derivatives possessed high in vivo potency as well. The most active ether derivatives under in vivo conditions were 4-(3-(3-(4-fluorophenyl)propyloxy)propyl)-1H-imidazole (11b) and the corresponding chloro compound 11c (FUB 181) with ED50 values of 0.76 and 0.80 mg/kg, respectively. On the other hand, all compounds tested showed weak activity at histamine H1 or H2 receptors. Furthermore, the most promising ether FUB 181 exhibited low activity at adrenergic alpha 1, beta 1/2, serotonergic 5-HT2A, 5-HT3, and muscarinic M3 receptors. Time-course investigations of FUB 181 in mice showed a rapid mode of action with the highest value 3 h after p.o. application. Thus, FUB 181 appears to block histamine H3 receptors potently and selectively.  相似文献   

14.
The role of beta3- and other putative atypical beta-adrenoceptors in human white adipocytes and right atrial appendage has been investigated using CGP 12177 and novel phenylethanolamine and aryloxypropanolamine beta3-adrenoceptor (beta3AR) agonists with varying intrinsic activities and selectivities for human cloned betaAR subtypes. The ability to demonstrate beta1/2AR antagonist-insensitive (beta3 or other atypical betaAR-mediated) responses to CGP 12177 was critically dependent on the albumin batch used to prepare and incubate the adipocytes. Four aryloxypropanolamine selective beta3AR agonists (SB-226552, SB-229432, SB-236923, SB-246982) consistently elicited beta1/2AR antagonist-insensitive lipolysis. However, a phenylethanolamine (SB-220646) that was a selective full beta3AR agonist elicited full lipolytic and inotropic responses that were sensitive to beta1/2AR antagonism, despite it having very low efficacies at cloned beta1- and beta2ARs. A component of the response to another phenylethanolamine selective beta3AR agonist (SB-215691) was insensitive to beta1/2AR antagonism in some experiments. Because no [corrected] novel aryloxypropanolamine had a beta1/2AR antagonist-insensitive inotropic effect, these results establish more firmly that beta3ARs mediate lipolysis in human white adipocytes, and suggest that putative 'beta4ARs' mediate inotropic responses to CGP 12177. The results also illustrate the difficulty of predicting from studies on cloned betaARs which betaARs will mediate responses to agonists in tissues that have a high number of beta1- and beta2ARs or a low number of beta3ARs.  相似文献   

15.
Eu(Ⅲ)-Pyromellitic acid[PMA]-1,10-phenanthroline (phen) ternary luminescent complex was prepared in ethanol and water mixed solvent. The elemental analysis, inductively coupled plasma-atomic emission spectroscopy (ICP-AES) fourier-transform infrared spectroscopy (FT-IR) indicates that its chemical constitution is Eu4(PMA)3(phen)0.75·7H2O. TG-DTA curves indicated that the complex is heat stable at the temperature of 430 ℃. The XRD patterns showed that the complex is a new crystal different from the two ligands' structures. SEM image indicates that the complex is in block shape and disperses well. Photoluminescence (PL) analysis indicates that the complex emits Eu3 characteristic luminescence under ultraviolet excitation.  相似文献   

16.
The recovery process of HeLa continuous cells after prolonged storage at nitrogen liquid temperature (--196 degrees C) has been analysed. The karyologic analysis evidence indicates a high stock cell karyostability. A study of cell division, generation cycle parameters and DNA synthesis by autoradiography demonstrated cell adaptation to a continuous passage to be due to the increase of proliferative pool and to the intensitification of generation processes in the multiplicated population. Cell structure changes during adaptation were reversible.  相似文献   

17.
Among the recently reported 2-(ar)alkynyl derivatives of 5'-N-ethylcarboxamidoadenosine (NECA), the (R,S)-2-(3-hydroxy-3-phenyl-1-propyn-1-yl)NECA [(R,S)-PHPNECA or SCH 59761] was found to be a very potent agonist at A1 and A2A receptor subtypes, with a Ki of 2.5 nM and 0.9 nM, respectively. Furthermore, this compound showed an inhibitory activity on platelet aggregation 16-fold higher than NECA, being the most potent anti-aggregatory nucleoside reported so far. Since this compound bears a chiral carbon in the side chain, the diastereoisomer separation was undertaken both by chiral HPLC and by a stereospecific synthetic method. Binding assays have shown that the (S)-diastereomer is about fivefold more potent and selective than the (R)-diastereomer as agonist of the A2A receptor subtype [(S)-PHPNECA, KiA2A = 0.5 nM; (R)-PHPNECA, KiA2A = 2.6 nM]. Functional studies indicated that (S)-PHPNECA possesses marked vasodilating activity and produces a relevant decrease in heart rate. Moreover, the (S)-diastereomer proved to be about ten times more potent than the (R)-diastereomer in inducing cardiovascular effects, in in vivo hemodynamic studies. However, the greatest difference between these two enantiomers resulted in the platelet aggregation test: in fact, the (R)-diastereomer displayed an inhibitory activity similar to that of NECA, whereas the (S)-diastereomer was 37-fold more active than NECA as an inhibitor of rabbit platelet aggregation, induced by ADP. These data suggest that (S)-PHPNECA could be a useful tool to investigate the mode of binding of agonists to the platelet adenosine receptor subtype.  相似文献   

18.
Sodium 2-[[4-(3-methoxypropoxy)-3-methylpyridin-2-yl]methylsulfinyl ]- 1H-benzimidazole (E3810) and omeprazole inhibit gastric acid secretion through inhibition of the activity of H+, K(+)-ATPase present in parietal cell membrane vesicles, by chemical modification of SH groups in the enzyme molecule. In order to clarify the mechanism of the chemical modification, reaction products of E3810 and omeprazole with 2-mercaptoethanol under acidic conditions (pH 3, 4, 5, 6) were isolated by HPLC, and subjected to structural analysis by UV, 1H-NMR and mass spectrometry. E3810 and omeprazole appeared to undergo two kinds of reactions, affording disulfide-type products (type I reaction) and sulfide-type products (type II reaction). The rates of these reactions were determined by HPLC, and the stability of the products in the presence and absence of glutathione was investigated. In the case of E3810, type I reaction was found to proceed faster than type II reaction at every pH value studied. The type I reaction of E3810 was faster than that of omeprazole. The rate of type I reaction decreased at pH 5 and 6, especially for omeprazole, and the contribution of type II reaction increased as the pH of the reaction mixture was increased. The sulfide-type modification products were stable, whereas the formation of the disulfide-type modification products was reversed by the action of endogenous SH compounds such as glutathione. These results suggest that higher inhibitory activity of E3810 against gastric acid secretion and faster recovery of the enzyme activity after inhibition by E3810 can be expected, as compared with those of omeprazole.  相似文献   

19.
OBJECTIVE: to evaluate the effectiveness of a reduced-frequency prenatal visit schedule by comparing perinatal outcomes, anxiety and maternal satisfaction with prenatal care. METHODS: pregnancy outcomes of infant and maternal morbidity and mortality, anxiety and satisfaction for 81 women receiving prenatal care at a free-standing birthing center according to either an alternative prenatal care visit schedule (APCVS) (n = 43) or the traditional prenatal care visit schedule (TPCVS) (n = 38) were examined in this prospective randomized study. Upon entry into prenatal care, all women were of low obstetrical risk status. RESULTS: major findings revealed no significant differences in selected perinatal outcomes between the two study groups. Women in the APCVS group reported significantly higher levels of satisfaction than women in the TPCVS group on both the satisfaction with provider subscale (F = 5.74, P = .02) and the satisfaction with the prenatal care system subscale (F = 2.01, P = .04). There were no statistically significant differences found in anxiety scores between women in the two study groups. CONCLUSIONS: low-risk women who followed the reduced-frequency visit schedule experienced no difference in perinatal outcomes or anxiety. Women in the reduced-frequency (APCVS) group reported an increased level of satisfaction with both provider and the prenatal care system.  相似文献   

20.
The synthesis of a range of 3-hydroxy-4(1H)-pyridinones with potential for the chelation of iron(III) is described. The pKa values of respective ligands and the stability constants of their iron(III) complexes are presented. The distribution coefficient values of a range of 48 hydroxypyridinones and their corresponding iron(III) complexes between 1-octanol and MOPS buffer (pH 7.4) are reported. The range of log Dcomplex values covers 7 orders of magnitude. The results suggest the existence of a biphasic relationship between the distribution coefficient values of the chelator and the corresponding iron(III) complexes. For ligands with a log Dligand = -1, a linear relationship exists with a value of the slope 2.53, whereas with ligands with a log Dligand < -1, a linear relationship exists with a slope of 0.49. The reduced slope for the more hydrophilic molecules of the series offers some advantage for this type of hydroxypyridinone as the distribution coefficients for such complexes do not change so rapidly with increasing ligand hydrophilicity. The ability of selected 3-hydroxypyridinones to facilitate the excretion of iron in bile was investigated in non-iron-overloaded, bile duct-cannulated rats and in a [59Fe]ferritin-loaded rat model. Both systems compare the ability of chelators to remove iron from the liver, the prime target organ in thalassemia. The N-(hydroxyalkyl)-3-hydroxypyridin-4-ones are demonstrated to be orally active under the in vivo conditions adopted. Thus both 1-(hydroxyalkyl)- and 1-(carboxyalkyl)pyridinones are able to remove iron from the liver. Although 1-(carboxyalkyl)hydroxypyridinones are active, they do not demonstrate any clear advantage over Deferiprone (1,2-dimethyl-3-hydroxypyridin-4-one). Indeed 1-(hydroxyalkyl)hydroxypyridinones which are known to be rapidly converted to 1-(carboxyalkyl)hydroxypyridinones are also marginally superior to Deferiprone. In contrast, 2-ethyl-1-(2'-hydroxyethyl)-3-hydroxypyridin-4-one, which is not metabolized to the corresponding (carboxyalkyl)hydroxypyridinone, was found to be superior to Deferiprone and therefore deserves further consideration as an orally active iron chelator with potential for the treatment of iron overload associated with transfusion-dependent thalassemia.  相似文献   

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