Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thirty-four girls with precocious puberty (27 idiopathic, 6 cerebral, 1 McCune-Albright syndrome) were treated with cyproterone acetate (CPA) for 1.2-8.4 years (3.71 +/- 0.31; mean +/- SEM) at a daily dosage of 66-150 mg/m2 (103.7 +/- 6.2). The mean chronological age (CA) and bone age at the beginning of treatment were 5.99 +/- 0.31 and 8.6 +/- 0.39 years, respectively, and 9.78 +/- 0.19 and 12.44 +/- 0.22 years, respectively, at the end of therapy. At the last evaluation, mean CA was 14.23 +/- 0.4 years, and 32 girls had reached final height. The control group consisted of 10 girls with idiopathic precocious puberty who, at their parents' request, were not treated. Mean CA at the onset of pubertal signs was 6.05 +/- 0.25 years. All patients had reached final height at the time of the last observation. There was no significant difference between final height of treated (152.43 +/- 1.36 cm) and untreated (149.55 +/- 1.99 cm) girls. Final height was significantly lower than target height in both treated (155.08 +/- 0.92 cm; p < 0.025) and untreated (156.45 +/- 1.29 cm; p < 0.0005) patients, but the mean height of treated patients is nearer to target height than that of untreated ones. A positive correlation was found between final height and target height both in treated (p < 0.005) and untreated (p < 0.05) patients. After the discontinuation of CPA treatment all girls resumed the progressive course of puberty.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Final height attainment and gonadal function in girls with precocious puberty treated with cyproterone acetate. 147 28

Forty-four patients (42 f, 2 m) with precocious puberty (31 idiopathic, 1 familial, 7 cerebral, 5 McCune-Albright) were treated with cyproterone acetate for periods of 1-8.75 years in different (P less than 0.05) daily dosages of 117 +/- 6.1 mg/m2 per day (mean +/- SEM, group A, N = 20) and 60.8 +/- 2.42 mg/m2 per day (group B, N = 24). Thirty-three girls had experienced menarche before therapy at a mean age of 4.89 +/- 0.42 years. Treatment was started at a chronologic age of 5.45 +/- 0.33 years in the girls and 5.74 +/- 1.34 years in the boys. At the time of evaluation, 31 of our patients had reached final height. With respect to the effects of treatment on statural growth, the Standard Deviation Scores were retrospectively determined for height, weight, and growth velocity. The initial Bayley-Pinneau height predictions were compared with final height and target height, and the skeletal maturation was studied. There were no significant differences between those parameters in the patients of group A and B or between treated and untreated subjects as far as final height and target height were concerned. It is concluded that cyproterone acetate administered orally at daily doses from 50-150 mg/m2 does not improve statural growth of patients with precocious puberty.
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PMID:The effects of cyproterone acetate on statural growth in children with precocious puberty. 295 58

Ordered macroporous organosilica materials with uniform pore size in the range of 0.2-1.35 [micro sign]m have been fabricated by using self-assembled colloidal crystals as templates, and characterized with SEM, TGA, FTIR, MAS NMR, and optical reflectance spectrometry.
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PMID:Synthesis, characterization and optical properties of ordered macroporous organosilicas. 1517 72

Calcium phosphate growth on chitin phosphorylated fibres was studied using scanning electron microscopy and energy dispersive X-ray analysis (SEM, EDX), micro-Fourier transform infrared spectroscopy (FTIR), and solid state magic angle spinning nuclear magnetic resonance (MAS NMR) techniques. The C6 chemical shift positions of 13C MAS NMR in the chitin fibres phosphorylated using urea and H3PO4 are obvious indicating that phosphorylation takes place not in the C1 but in the C6 region. Micro-FTIR and 31P MAS NMR suggested that ammonium hydrogen phosphate formed during the phosphorylation procedure. Chitin fibres phosphorylated using urea and H3PO4 and then soaked in saturated Ca(OH)2 solution at ambient temperature, which lead to the formation of thin coatings formed by partial hydrolysis of the PO4 functionalities, were found to stimulate the growth of a calcium phosphate coating on their surfaces after soaking in 1.5xSBF solution for as little as one day. The thin layer after Ca(OH)2 treatment functioned as a nucleation layer for further calcium phosphate deposition after soaking in 1.5xSBF solution. EDX-measured Ca : P ratios of the coatings of Ca(OH)2-treated phosphorylated chitin in 1.5xSBF solution suggested that calcium-deficient apatite was formed.
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PMID:Growth of calcium phosphate on phosphorylated chitin fibres. 1534 22

Two different rehydration procedures in the liquid or gas phase have been applied to reconstruct mixed oxides derived from calcined hydrotalcite-like materials to be used as catalysts for aldol condensation reactions. The as-synthesized hydrotalcite, its decomposition product, as well as the reconstructed solids upon rehydration were characterized by XRD, N(2) adsorption, He pycnometry, FTIR, SEM, TEM, (27)Al MAS-NMR and CO(2)-TPD (TPD=temperature-programmed desorption). Compared to the Mg-Al mixed oxide rehydrated in the gas phase (HT-rg), that rehydrated in the liquid phase (HT-rl) exhibits a superior catalytic performance with respect to the aldol condensation of citral with ketones to yield pseudoionones and in the self-aldolization of acetone. The textural properties of HT-rl and HT-rg differ strongly and determine the catalytic behavior. A memory effect led to a higher degree of reconstruction of the lamellar structure when the mixed oxide was rehydrated in the gas phase rather than in the liquid phase, although liquid-phase rehydration under fast stirring produced a surface area that was 26 times greater. This contrasts to typical statements in the literature claiming a higher degree of reconstruction in the presence of large amounts of water in the medium. CO(2)-TPD shows that the number of OH(-) groups and their nature are very similar in HT-rg and HT-rl, and cannot explain the markedly different catalytic behavior. Accordingly, only a small fraction of the available basic sites in the rehydrated samples is active in liquid-phase aldol condensations. Our results support the model in which only basic sites near the edges of the hydrotalcite platelets are partaking in aldol reactions. Based on this, reconstructed materials with small crystallites (produced by exfoliation during mechanical stirring), that is, possessing a high external surface area, are beneficial in the reactions compared to larger crystals with a high degree of intraplatelet porosity.
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PMID:Aldol condensations over reconstructed Mg-Al hydrotalcites: structure-activity relationships related to the rehydration method. 1558 78

Physicochemical properties of sodium alginate-magnesium aluminum silicate (SA-MAS) composite films were investigated and a potential as a film former of SA-MAS dispersion for modifying drug release from tablets was evaluated as well. Interaction between SA and MAS in the composite films was revealed using FTIR spectroscopy. Thermal behavior of the composite films was changed due to the complexation of SA and MAS. Powder X-ray diffractometry data suggested that a higher crystallinity of the composite film and a phase-separated microcomposite were formed. The composite films in the ratios of 1:0.5 and 1:1 showed the increases of tensile strength and percentage of elongation when compared with SA films. Water vapor permeability of the composite films tended to increase with increasing ratio of MAS. The decreases in water uptake and drug permeability in 0.1 M HCl were found in the composite films. A positive charge drug, propranolol HCl, provided a higher affinity on the composite films than a weakly acidic nonelectrolyte, acetaminophen, resulting in a longer lag time and a higher partition coefficient depending on the content of MAS in the composite films. This was due to the complex formation of propranolol HCl and MAS. Using SEM, the tablets coated with SA-MAS dispersion had a smooth surface, while those with SA dispersion showed a pinholing on the surface, resulting in a faster drug release. The drug release profiles of the tablets could be modified by coating with the composite film at different coating levels. This finding suggests that MAS could improve physicochemical properties of the SA films, leading to a novel coating material of the SA-MAS dispersion for modifying drug release from tablets.
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PMID:Investigation of novel alginate-magnesium aluminum silicate microcomposite films for modified-release tablets. 1606 2

Composites based on phenolic matrices and unmodified and chemically modified sugar cane bagasse and curaua fibers were prepared. The fibers were oxidized by chlorine dioxide, mainly phenolic syringyl and guaiacyl units of the lignin polymer, followed by grafting furfuryl alcohol (FA), which is a chemical obtained from a renewable source. The fibers were widely characterized by chemical composition analysis, crystallinity, UV-vis diffuse reflectance spectroscopy, SEM, DSC, TG, tensile strength, and 13C CP-MAS NMR. The composites were analyzed by SEM, impact strength, and DMA. The SEM images and DMA results showed that the oxidation of sugar cane bagasse fibers followed by reaction with FA favored the fiber/matrix interaction at the interface. The same chemical modification was less effective for curaua fibers, probably due to its lower lignin content, since the reaction considered touches mainly the lignin moiety. The tensile strength results obtained showed that the fibers were partially degraded by the chemical treatment, decreasing then the impact strength of the composites reinforced with them. In the continuity of the present project, efforts has been addressed to the optimization of fiber surface modification, looking for reagents preferably obtained from renewable resources and for chemical modifications that intensify the fiber/matrix interaction without loss of mechanical properties.
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PMID:Thermoset phenolic matrices reinforced with unmodified and surface-grafted furfuryl alcohol sugar cane bagasse and curaua fibers: properties of fibers and composites. 1615 84

In this study, the feasibility of preparing effective adsorbents from unmitigated agroforestry wastes was investigated. Three different kinds of carbon-like materials were produced by low temperature pyrolysis (LTC, <500 degrees C) of the raw materials rice husks, eucalyptus sawdust and peach stones. The carbon-like materials were characterized by instrumental methods (SEM,X-RDS,BET,MAS-RMN,FTIR), physico-chemical adsorption (iodine-, methylene blue- and phenazone-number; acetic acid adsorption isotherm; textile dyes- and carbohydrate adsorption), and heat value determination. The produced materials, which showed appreciable adsorption capacity, can be considered as precursors for the production of active coal or even be used directly as well.
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PMID:Low temperature conversion of rice husks, eucalyptus sawdust and peach stones for the production of carbon-like adsorbent. 1679 Mar 41

Amorphous mesoporous aluminophosphates (AlPO) with P/Al molar ratio in the range 0.8-1.15 are synthesized by using the citric acid (CA) route and are systematically characterized using N(2)-adsorption, XRD, SEM, solid-state CP-MAS NMR, FT-IR, TG-DTA, CO(2)-TPD, and NH(3)-TPD. The characterization studies show that the change in P/Al ratio could affect the structure, texture, thermal stability, and surface acid-base properties of AlPO. Samples with a relatively low P/Al ratio (< or =1.0) exhibit uniform amorphous mesoporous character and high thermal stability (up to 1173 K). Partial crystallization of the AlPO framework easily occurred on the sample with higher P/Al ratio (> or =1.1), thus leading to significant decrease of surface area and formation of particle pile mesopores. Both weak acid and weak base sites are observed over AlPO materials, and the amounts of acid-base sites can be effectively controlled by adjusting the P/Al ratio. The presence of suitable interaction between citric acid and AlPO framework is critical for the formation of mesoporous structures. Both CA and PO(4) units are considered to be ligands to coordinate with aluminum ions, forming relative uniform complexes (such as CA-Al-PO(4)) in the as-synthesized AlPO materials. The mesoporous structure of AlPO materials is obtained after the rapid decomposition of citric acid. Vapor phase selective O-methylation of catechol with methanol reaction is carried out to investigate the catalytic performances of AlPO materials with different P/Al ratios. Among them, AlP(1.1)O shows the highest activity (88.4% conversion of catechol) and the highest yield of guaiacol (74.3%). The presence of suitable weak acid-base pairs may play an important role on the title reaction.
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PMID:Thermally stable amorphous mesoporous aluminophosphates with controllable P/Al ratio: synthesis, characterization, and catalytic performance for selective O-methylation of catechol. 1692 87

New, thermally robust meso- and macroporous carbon powders were prepared by ultrasonic spray pyrolysis (USP) of aqueous solutions using an inexpensive high-frequency ultrasound generator from a household humidifier. We choose our molecular precursors rationally, so that the expected decomposition pathways produce only remnant carbon atoms. Specifically, our rational design criterion led to halo-organic carboxylate salts, whose pyrolysis yields well-defined carbon solids with a temporary template being generated in situ, simply an inorganic salt, which is easily dissolved during aqueous workup. The materials have been characterized by SEM, TEM, XRD, 13C NMR MAS, XPS, FTIR spectroscopy, and BET surface area measurements. Changing the alkali metal alters the morphology and pore structure of the final material, which can be explained in terms of the observed differences in the DSC and TGA of the various precursors. This preparatory method provides an extremely facile and versatile method for the generation of meso- and macroporous carbons.
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PMID:Porous carbon powders prepared by ultrasonic spray pyrolysis. 1700 46


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