975 resultados para 2 alpha-dihydro-20-palimoyldaphnetoxin


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A new daphnane diterpene was isolated from the root barks of Daphne tangutica Maxim. Its structure was elucidated as 1, 2 alpha-dihydro-20-palimoyldaphnetoxin by the spectroscopic evidence including 2D-NMR.

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Knowledge of the effectiveness of prostaglandins in uterine involution process led to the development of protocols with its analogues in postpartum period. However, this hormone mechanism of action is not yet fully elucidated. Thus, the objective of this study was to verify if chloprostenol administration, at early or intermediary puerperium, can induce changes on progesterone, PGFM and oestradiol plasma concentrations. 30 Murrah postpartum buffaloes were randomly divided into three groups: CONT (saline, n = 10); CLO2 (chloprostenol at days 2 and 5 postpartum, n = 10) and; CLO15 (chloprostenol at days 15 and 20 postpartum, n = 10). Blood samples were collected from jugular vein to measure progesterone, PGFM and oestradiol plasma concentrations at days 2, 7, 14, 21 and 28 postpartum. CLO2 group presented lower progesterone and PGFM plasma concentrations in relation to CONT and CLO15 groups (0.23 +/- 0.00 and 0.32 +/- 0.11, 0.19 +/- 0.00 and 0.23 +/- 0.11, 0.23 +/- 0.00 and 0.30 +/- 0.19, for groups CONT, CLO2 and CLO15, respectively; P < 0.05). There was no significant difference in oestradiol plasma concentration between experimental groups (P > 0.05). Prostaglandin synthetic analogue administration induced hormonal changes in postpartum buffaloes, which can partially explain its positive effect under reproductive function of this specie.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The canine corpus luteum (CL) typically sustains elevated plasma progesterone concentrations for 2 months or more, with a peak approximately 15-25 days after ovulation, followed by a slow decline. The processes involved in the slow, protracted regression of the CL over the remaining 1.5-2-month period in nonpregnant bitches and until shortly prepartum in pregnant bitches are not well characterized. The rapid luteolysis that occurs immediately prepartum appears to be a result of a prepartum rise in peripheral PGF. The potential role of PGF in the slow regression process in the several weeks preceding parturition and in nonpregnant bitches after 15-25 days after ovulation is not known. Therefore, plasma concentrations of 13,14-dihydro-15-keto-prostaglandin F-2-alpha (PGFM), progesterone (P-4) and estradiol (E-2) Were determined and compared in bitches during nonpregnant diestrus (n = 9) or pregnancy (n = 8). During the gradual decrease in plasma concentrations of progesterone in both groups, the P-4 pattern appeared unrelated to changes in either E-2 or PGFM concentrations. The PGFM pattern was different between diestrus and pregnant bitches (P > 0.01); there was an apparent progressive but slow increase in PGFM in pregnant bitches from Days 30 to 60, followed by a large increase prior to parturition; concentrations declined immediately postpartum. However, there were no increases in PGFM during the same interval in nonpregnant bitches. Mean estradiol concentrations were sporadically elevated during the last third of pregnancy and less so in nonpregnant diestrus; there was no acute prepartum increase in estradiol associated with the PGFM increase. In summary, although there were no apparent changes in peripheral PGF(2)alpha concentration involved in regulating the slow protracted phase of luteal regression in nonpregnant bitches, modest increases in PGFM may play a role in ovarian function after mid-gestation in pregnant bitches. Furthermore, the acute prepartum rise in PGFM was not dependent on any concomitant increase in estradiol concentrations. (c) 2006 Elsevier B.V. All rights reserved.

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The study evaluated, in early post-partum anoestrous Nelore cows, if the increase in plasma oestradiol (E2) concentrations in the pre-ovulatory period and/or progesterone priming (P4 priming) preceding ovulation, induced by hormonal treatment, reduces the endogenous release of prostaglandin PGF(2)alpha and prevents premature lysis of the corpus luteum (CL). Nelore cows were subjected to temporary calf removal for 48 h and divided into two groups: GPE/eCG group (n = 10) and GPG/eCG group (n = 10). Animals of the GPE/eCG group were treated with a GnRH agonist. Seven days later, they received 400 ID of eCG, immediately after PGF(2)alpha treatment, and on day 0, 1.0 mg of oestradiol benzoate (EB). Cows of the GPG/eCG group were similarly treated as those of the GPE/eCG group, except that EB was replaced with a second dose of GnRH. All animals were challenged with oxytocin (OT) 9, 12, 15 and 18 days after EB or GnRH administration and blood samples were collected before and 30 min after OT. Irrespective of the treatments, a decline in P4 concentration on day 18 was observed for cows without P4 priming. However, animals exposed to P4 priming, treated with EB maintained high P4 concentrations (8.8 +/- 1.2 ng/ml), whereas there was a decline in P4 on day 18 (2.1 +/- 1.0 ng/ml) for cows that received GnRH to induce ovulation (p < 0.01). Production of 13,14-dihydro-15-keto prostaglandin F-2 alpha (PGFM) in response to OT increased between days 9 and 18 (p < 0.01), and this increase tended to be more evident in animals not exposed to P4 priming (p < 0.06). In conclusion, the increase in E2 during the pre-ovulatory period was not effective in inhibiting PGFM release, which was lower in P4-primed than in non-primed animals. Treatment with EB promoted the maintenance of elevated P4 concentrations 18 days after ovulation in P4-primed animals, indicating a possible beneficial effect of hormone protocols containing EB in animals with P4 priming.

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193头健康、经产的黑白花奶牛分为3个组,用3种不同的方法进行同期发情处理和胚胎移植。第1组:注射1次Lutalyse;第2组:注射2次Lutalyse;第3组:注射Fertagyl-Lutalyse-Fertagyl。结果表明:第1组和第2组之间的同期发情胚胎移植率无显著差异(P>0.05),分别为26.5%(21/79)和27.0%(18/68);第3组的同期发情胚胎移植率为60.9%(28/46),显著高于第1组和第2组(P<0.05)。

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In this paper, 20 kinds of different 2-(alpha-arylamino phosphonate)-chitosan (2-alpha-AAPCS) were prepared by different Schiff bases of chitosan (CS) reacted with di-alkyl phosphite in benzene solution. The structures of the derivatives (2-alpha-AAPCS) were characterized by FT-IR spectroscopy and elemental analysis. In addition, the antifungal activities of the derivatives against four kinds of fungi were evaluated in the experiment. The results indicated that all the prepared 2-alpha-AAPCS had a significant inhibiting effect on the investigated fungi when the derivatives concentration ranged from 50 to 500 mu g mL(-1). Furthermore, the antifungal activities of the derivatives increased with increasing the molecular weight and concentration. And the antifungal activities of the derivatives were affected by their dimensional effect and charge density. Besides, the rule and mechanism of the antifungal activities of them were discussed in this paper. (C) 2009 Elsevier B.V. All rights reserved.

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This paper presents the structural characterization of the indan derivative (+/-)-1-trans-3-(3,4-dichlorophenyl)-2,3-dihydro-1H-indene-1-carboxamide, which was unambiguously determined by X-ray diffraction (XRD) to be a racemate (R/S: 50/50) crystallizing in an achiral crystal structure (P2(1)/c, a = 9.3180(1) , b = 7.9070(2) , c = 19.7550(4) , beta = 103.250(1)A degrees, V = 1416.75(5) (3) and Z = 4). The diastereomers are related by the inversion symmetry and linked by H bond forming a dimer. The crystal packing is stabilized by hydrogen bonds, including the classical one responsible for the formation of centrosymmetric dimers, and non-classical ones involving C-H center dot center dot center dot O and C-H center dot center dot center dot pi-aryl interactions. The intra and intermolecular geometry of the title compound is compared to the (+/-)-1-trans-3-(3,4-dichlorophenyl)-2,3-dihydro-1H-indene-1-carboxylic acid one, which also present an achiral crystal structure from racemates (R/S: 50/50). The two indan derivatives crystallize in a very similar unit cell.

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The structure-activity relationship optimization of the pyrazoline template 3a resulted in novel 3-oxo-1,2-diphenyl-2,3-dihydro-1H-pyrazol-4-yl)-indole carboxamides 4a-4e. These non-peptidal CCK ligands have been shown to act as potent CCK 1 ligands in a [125]I-CCK-8 receptor binding assay. The best amides (4c and 4d) of this series displayed an IC50 of 20/25 CCK 1 for the CCK 1 receptor. In a subsequent in-vivo evaluation using various behaviour pharmacological assays, an anxiolytic effect of these novel 3-oxo-1,2-diphenyl-2,3-dihydro-1H-pyrazol-4-yl)-indole carboxamides was found at high doses in the elevated plus-maze. In the despair swimming test, a model for testing antidepressants, an ED50 of 0.33/0.41 mg kg -1 was determined for amide 4c/4d and the antidepressant effect had a magnitude comparable to desimipramine. © 2006 The Authors.

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A new diketopyrrolopyrrole (DPP)-containing donor-acceptor polymer, poly(2,5-bis(2-octyldodecyl)-3,6-di(furan-2-yl)-2,5-dihydro-pyrrolo[3,4-c] pyrrole-1,4-dione-co-thieno[3,2-b]thiophene) (PDBF-co-TT), is synthesized and studied as a semiconductor in organic thin film transistors (OTFTs) and organic photovoltaics (OPVs). High hole mobility of up to 0.53 cm 2 V -1 s -1 in bottom-gate, top-contact OTFT devices is achieved owing to the ordered polymer chain packing and favoured chain orientation, strong intermolecular interactions, as well as uniform film morphology of PDBF-co-TT. The optimum band gap of 1.39 eV and high hole mobility make this polymer a promising donor semiconductor for the solar cell application. When paired with a fullerene acceptor, PC 71BM, the resulting OPV devices show a high power conversion efficiency of up to 4.38% under simulated standard AM1.5 solar illumination.

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Solution processable diketopyrrolopyrrole (DPP)-bithiophene polymers (PDBT) with long branched alkyl side chains on the DPP unit are synthesized. These polymers have favourable highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels for the injection and transport of both holes and electrons. Organic thin film transistors (OTFTs) using these polymers as semiconductors and gold as source/drain electrodes show typical ambipolar characteristics with very well balanced high hole and electron mobilities (μ h = 0.024 cm 2 V -1 s -1 and μ e = 0.056 cm 2 V -1 s -1). These simple and high-performing polymers are promising materials for ambipolar organic thin film transistors for low-cost CMOS-like logic circuits.

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CIoH15NO282, Mr=245"0, orthorhombic, P21212 ~, a = 6.639 (2), b = 8.205 (2), c = 22.528(6)A, V= I227.2(6)A 3, z=4, Dm= 1.315, Dx= 1.326gem -3, MoKa, 2=0.7107A, 12= 3.63 cm -1, F(000) = 520, T= 293 K, R = 0.037 for 1115 significant reflections. The second-harmonicgeneration (SHG) efficiency of this compound is only 1/10th of the urea standard. The observed low second-order nonlinear response may be attributed to the unfavourable packing of the molecules in the crystal lattice.

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The aim of this study was to investigate the effects on follicle stimulating hormone (FSH) secretion and dominant follicle (OF) growth, of treatment of Bos indicus heifers with different combinations of intra-vaginal progesterone releasing devices (IPRD), oestradiol benzoate (ODB), PGF(2 alpha), and eCG. Two-year-old Brahman (BN; n=30) and Brahman-cross (BNX; n=34) heifers were randomly allocated to three IPRD-treatments: (i) standard-dose IPRD [CM 1.56 g; 1.56 g progesterone (P-4); n = 17]; (ii) half-dose IPRD (CM 0.78 g; 0.78 g p(4); n=15); (iii) half-dose IPRD + 300 IU eCG at IPRD removal (CM 0.78 g+G; n=14); and, (iv) non-IPRD control (2 x PGF(2 alpha); n=18) 500 mu g cloprostenol on Days -16 and -2. IPRD-treated heifers received 250 mu g PGF(2 alpha) at IPRD insertion (Day 10) and IPRD removal (Day -2) and 1 mg ODB on Day -10 and Day -1. Follicular dynamics were monitored daily by trans-rectal ultrasonography from Day -10 to Day 1. Blood samples for determination of P-4 were collected daily and samples for FSH determination were collected at 12 h intervals from Day -9 to Day -2. A significant surge in concentrations of FSH was observed in the 2 x PGF(2 alpha), treatment 12 h prior and 48 h after follicular wave emergence, but not in the IPRD-treated heifers. Estimated mean concentrations of total plasma P-4 during the 8 days of IPRD insertion was greater (P<0.001) in the CM 1.56 g P-4 treated heifers compared to the CM 0.78 g P-4 treated heifers (18.38 ng/ml compared with 11.09 ng/ml, respectively). A treatment by genotype interaction (P=0.036) was observed in the mean plasma P4 concentration in heifers with no CL during IPRD insertion, whereby BN heifers in the CM 1.56 g treatment had greater plasma P-4 than the BNX heifers on Days-9, -7, -6, -5, and -4. However, there was no genotype effect in the CM 0.78 g +/- G or the 2 x PGF(2 alpha) treatment. Treatment had no effect on the DF growth from either day of wave emergence (P=0.378) or day of IPRD removal (P=0.780) to ovulation. This study demonstrates that FSH secretion in B. indicus heifers treated with a combination of IPRD's and ODB to synchronise ovulation was suppressed during the period of IPRD insertion but no significant effect on growth of the DF was observed. (C) 2013 Elsevier B.V. All rights reserved.