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101.
Reaction of the ligands 3-phenyl-5-(2-pyridyl)pyrazole (HL1), 3,5-bis(2-pyridyl)pyrazole (HL2), 3-methyl-5-(2-pyridyl)pyrazole (HL3) and 3-methyl-5-phenylpyrazole (HL4) with [MCl2(CH3CN)2] (M = Pd(II), Pt(II)) or [PdCl2(cod)] gives complexes with stoichiometry [PdCl2(HL)2] (HL = HL1, HL2, HL3), [Pt(L)2] (L = L1, L2, L3) and [MCl2(HL4)2] (M = Pd(II), Pt(II)). The new complexes were characterised by elemental analyses, conductivity measurements, infrared and 1H NMR spectroscopies. The crystal and molecular structure of [PdCl2(HL1)] was resolved by X-ray diffraction, and consists of monomeric cis-[PdCl2(HL1)] molecules. The palladium centre has a typical square planar geometry, with a slight tetrahedral distortion. The tetra-coordinated metal atom is bonded to one pyridine nitrogen, one pyrazolic nitrogen and two chloro ligands in a cis disposition. The ligand HL1 is not completely planar. 相似文献
102.
The purpose of this research was to evaluate the influence of dry granulation parameters on granule and tablet properties
of spray-dried extract (SDE) fromMaytenus ilicifolia, which is widely used in Brazil in the treatment of gastric disorders. The compressional behavior of the SDE and granules
of the SDE was characterized by Heckel plots. The tablet properties of powders, granules, and formulations containing a high
extract dose were compared. The SDE was blended with 2% magnesium stearate and 1% colloidal silicon dioxide and compacted
to produce granules after slugging or roll compaction. The influences of the granulation process and the roll compaction force
on the technological properties of the granules were studied. The flowability and density of spray-dried particles were improved
after granulation. Tablets produced by direct compression of granules showed lower crushing strength than the ones obtained
from nongranulated material. The compressional analysis by Heckel plots revealed that the SDE undergoes plastic deformation
with a very low tendency to rearrangement at an early stage of compression. On the other hand, the granules showed an intensive
rearrangement as a consequence of fragmentation and rebounding. However, when the compaction pressure was increased, the granules
showed plastic deformation. The mean yield pressure values showed that both granulation techniques and the roll compaction
force were able to reduce the material's ability to undergo plastic deformation. Finally, the tablet containing a high dose
of granules showed a close dependence between crushing strength and the densification degree of the granules (ie, roll compaction
force).
Published: October 14, 2005 相似文献
103.
Proteomic analysis using protein chips to detect biomarkers in cervical and amniotic fluid in women with intra-amniotic inflammation 总被引:1,自引:0,他引:1
Rüetschi U Rosén A Karlsson G Zetterberg H Rymo L Hagberg H Jacobsson B 《Journal of proteome research》2005,4(6):2236-2242
Intra-amniotic inflammation (IAI) may cause preterm birth with poor neonatal out-come. To identify novel biomarkers for IAI, we analyzed amniotic and cervical fluid samples from 27 patients with signs of threatening preterm birth with or without IAI by surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF-MS). Seventeen proteins were significantly overexpressed in amniotic fluid from IAI cases and more often in women with preterm labor than those with rupture of membranes. Five of these were identified as human neutrophil protein 1-3, calgranulin A and B. 相似文献
104.
105.
Garcia JL Gennari SM Navarro IT Machado RZ Sinhorini IL 《Experimental parasitology》2004,108(1-2):40-46
Rhoptries have been isolated from Toxoplasma gondii tachyzoites by subcellular fractionation in isopynic density sucrose gradient. Five bands were observed, and transmission electron microscopy of these indicated that rhoptries were in band 3. This band had a density of 1.17 g/cm(3). Fraction 1 had membrane structures of the parasite. Fraction 2 contained membranes and mitochondria. Fraction 4 had mostly conoid structure and fraction 5 showed ghosts. The electrophoretic and Western blotting analysis of the fractions indicated the presence of a number of proteins. Iscoms were constructed from band 3, which contained the rhoptry structures. Iscom showed a only protein incorporated of 55 kDa. Isolation of the parasite organelles has got in this work is necessary to identification, characterization, and function elucidation of the organelle proteins. 相似文献
106.
Ros M Sorensen D Waagepetersen R Dupont-Nivet M SanCristobal M Bonnet JC Mallard J 《Genetics》2004,168(4):2089-2097
Phenotypic plasticity and canalization are important topics in quantitative genetics and evolution. Both concepts are related to environmental sensitivity. The latter can be modeled using a model with genetically structured environmental variance. This work reports the results of a genetic analysis of adult weight in the snail Helix aspersa. Several models of heterogeneous variance are fitted using a Bayesian, MCMC approach. Exploratory analyses using posterior predictive model checking and model comparisons based on the deviance information criterion favor a model postulating a genetically structured heterogeneous environmental variance. Our analysis provides a strong indication of a positive genetic correlation between additive genetic values affecting the mean and those affecting environmental variation of adult body weight. The possibility of manipulating environmental variance by selection is illustrated numerically using estimates of parameters derived from the snail data set. 相似文献
107.
The ligands 1-hydroxymethylpyrazole (hl1), 1-(2-hydroxyethyl)pyrazole (hl2) and 1-(3-hydroxypropyl)pyrazole (hl3) react with [PdCl2(CH3CN)2] to give trans-[PdCl2(hl)2] compounds. Due to a hindered rotation around the Pd-bond, these compounds present two different conformations in solution: anti and syn. The conformation presented depends on the relative disposition of the hydroxyalkylic chains of the two pyrazolic ligands. The present study was carried out on the basis of NMR experiments. The present paper reports the crystal structure of trans-[PdCl2(hl2)2]. The synthesis and characterisation of compounds [Pd(hl)4](BF4)2 (hl = hl1, hl2 and hl3) starting from [Pd(CH3CN)4](BF4)2 and the corresponding chlorocomplexes trans-[PdCl2(hl)2] are also described. 相似文献
108.
The reactions of the triangulo-cluster [Pt3(μ-CO)3(PtBu3)3] with activated olefins and alkynes have been examined under various conditions. At low temperature, cluster fragmentation occurs yielding the Pt(0) complexes [Pt(CO)(PtBu3)(olefin)] (olefin = maleic anhydride and maleimide), while di(tert-butyl)acetylenedicarboxilate reacts quantitatively giving the dinuclear Pt(0) complex [Pt2(CO)2(PtBu3)2(μ-η2:η2-tBuO2CCCCO2tBu)]. At higher temperature and in the presence of alkyne in large excess, the latter dimer converts quantitatively to the monomers [Pt(CO)(PtBu3)(alkyne)] (alkyne = CF3CCCF3 and tBuO2CCCCO2tBu). The stereochemistry of these complexes has been established by NMR and IR measurements. The structure of [Pt(CO)(PtBu3)(CF3CCCF3)] was confirmed by X-ray diffraction analysis. 相似文献
109.
Rosén ML Edman M Sjöström M Wieslander A 《The Journal of biological chemistry》2004,279(37):38683-38692
Glycosyltransferases (GTs) are among the largest groups of enzymes found and are usually classified on the basis of sequence comparisons into many families of varying similarity (CAZy systematics). Only two different Rossman-like folds have been detected (GT-A and GT-B) within the small number of established crystal structures. A third uncharacterized fold has been indicated with transmembrane organization (GT-C). We here use a method based on multivariate data analyses (MVDAs) of property patterns in amino acid sequences and can with high accuracy recognize the correct fold in a large data set of GTs. Likewise, a retaining or inverting enzymatic mechanism for attachment of the donor sugar could be properly revealed in the GT-A and GT-B fold group sequences by such analyses. Sequence alignments could be correlated to important variables in MVDA, and the separating amino acid positions could be mapped over the active sites. These seem to be localized to similar positions in space for the alpha/beta/alpha binding motifs in the GT-B fold group structures. Analogous, active-site sequence positions were found for the GT-A fold group. Multivariate property patterns could also easily group most GTs annotated in the genomes of Escherichia coli and Synechocystis to proper fold or organization group, according to benchmarking comparisons at the MetaServer. We conclude that the sequence property patterns revealed by the multivariate analyses seem more conserved than amino acid types for these GT groups, and these patterns are also conserved in the structures. Such patterns may also potentially define substrate preferences. 相似文献
110.
Verónica Escurriol Montserrat Cofán Concepción Moreno-Iribas Nerea Larra?aga Carmen Martínez Carmen Navarro Laudina Rodríguez Carlos A. González Dolores Corella Emilio Ros 《Journal of lipid research》2010,51(3):618-624
Phytosterol intake with natural foods, a measure of healthy dietary choices, increases plasma levels, but increased plasma phytosterols are believed to be a coronary heart disease (CHD) risk factor. To address this paradox, we evaluated baseline risk factors, phytosterol intake, and plasma noncholesterol sterol levels in participants of a case control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) Spanish cohort who developed CHD (n = 299) and matched controls (n = 584) who remained free of CHD after a 10 year follow-up. Sitosterol-to-cholesterol ratios increased across tertiles of phytosterol intake (P = 0.026). HDL-cholesterol level increased, and adiposity measures, cholesterol/HDL ratios, and levels of glucose, triglycerides, and lathosterol, a cholesterol synthesis marker, decreased across plasma sitosterol tertiles (P < 0.02; all). Compared with controls, cases had nonsignificantly lower median levels of phytosterol intake and plasma sitosterol. The multivariable-adjusted odds ratio for CHD across the lowest to highest plasma sitosterol tertile was 0.59 (95% confidence interval, 0.36–0.97). Associations were weaker for plasma campesterol. The apolipoprotein E genotype was unrelated to CHD risk or plasma phytosterols. The data suggest that plasma sitosterol levels are associated with a lower CHD risk while being markers of a lower cardiometabolic risk in the EPIC-Spain cohort, a population with a high phytosterol intake. 相似文献