910 resultados para Differentiated products


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Smallanthus sonchifolius is a traditional Andean plant which has been cultured mainly in Brazil, Japan and New Zealand due to its medicinal properties. A study of the endophytic fungi associated to the plant was carried out in order to characterize new cytotoxic agents. Thirty two fungal strains were isolated and submitted to cultivation and extraction producing 186 extracts. Of these, 12% displayed moderate to high cytotoxic activities and were considered promising anticancer compound sources. The ethyl acetate fractions of Nigrospora sphaerica and Phoma betae liquid fermentations contained the synergistic compounds 8-hydroxy-6-methoxy-3-methylisocoumarin and (22E,24R)-ergosta-4,6,8(14),22-tetraen-3-one which are potential compounds for drug discovery. Another isolated compound, pimara-7,15-dien-3-beta-ol diterpene is being characterized for the first time through a detailed spectroscopic analysis including GC/MS, homo- and hetero-nuclear correlated NMR experiments (HMQC, HMBC, COSY and NOEdiff) along with its optical rotation.

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A gas product analysis has been conducted on gamma-irradiated samples of poly(lactic acid) (PLA) and poly(glycolic acid) (PGA) by means of gas chromatography. The major volatile products have been identified to be CO, CO2, CH4 and C2H6 for PLA, and CO and CO2 for PGA. In addition, the yield of evolved gases for PLA has been found to be 1.81 for CO2, 0.98 for CO, 0.026 for CH4 and 0.012 for C2H6; and that for PGA to be 1.70 for CO2 and 0.42 for CO. The new chain ends formed due to gamma-induced bond cleavage in PLA have been assigned to CH3-CH2-CO-O- and CH3-CH2-O-CO-, and the G values for formation of these chain ends were found to be 1.9 and 0.6, respectively. The G value for chain scission reported previously of 2.3 is comparable with that for the formation of the propanoic acid end group. (C) 1997 Elsevier Science Limited.

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Aims Topical sunscreens are routinely applied to the skin by a large percentage of the population. This study assessed the extent of absorption of a number of common chemical sunscreen agents into and through human skin following application of commercially available products. Methods Sunscreen products were applied to excised human epidermis in Franz diffusion cells with the amount penetrating into and across the epidermis assessed by h.p.l.c. for 8 h following application. Results All sunscreen agents investigated penetrated into the skin (0.25 g m(-2) or 14% of applied dose), but only benzophenone-3 passed through the skin in significant amounts (0.08 g m(-2) or 10% of the applied dose). With one exception, suncreen agents in corresponding products marketed for adults and children had similar skin penetration profiles. Conclusions Whilst limited absorption across the skin was observed for the majority of the sunscreens tested, benzophenone-3 demonstrated sufficiently high penetration to warrant further investigation of its continued application.

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Objective. Differentiated dendritic cells (DC) and other antigen-presenting cells are characterized by the nuclear location of RelB, a member of the nuclear factor kappa B/Rel family. To characterize and enumerate differentiated DC in rheumatoid arthritis (RA) peripheral blood (PB), synovial fluid (SF), and synovial tissue (ST), the expression and location of RelB were examined. Methods. RelB protein expression and cellular location were determined in RA PB, SF, and ST by flow cytometry and immunohistochemical analysis of purified cells or formalin-fixed tissue. DNA-binding activity of RelB was determined by electrophoretic: mobility shift-Western immunoblotting assays. Results. Circulating RA PBDC resembled normal immature PBDC in that they did not express intracellular RelB protein. In RA ST serial sections, cells containing nuclear RelB (nRelB) were enriched in perivascular regions. A mean +/- SD of 84 +/- 10% of these cells were DC. The remaining nRelB+,HLA-DR+ cells comprised B cells and macrophages. Only 3% of sorted SFDC contained nRelB, However, RelB present in the nucleus of these SFDC was capable of binding DNA, and therefore capable of transcriptional activity. Conclusion. Circulating DC precursors differentiate and express RelB after entry into rheumatoid ST. Differentiated DC can thus be identified by immunohistochemistry in formalin-fixed ST. Signals for DC maturation may differ between RA ST and SF, resulting in nuclear location of RelB predominantly in ST. This is likely to have functional consequences for the DC in these sites.

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A precise, reproducible deletion made during in vitro reverse transcription of RNA2 from the icosahedral positive-stranded Helicoverpa armigera stunt virus (Tetraviridae) is described. The deletion, located between two hexamer repeats, is a 50-base sequence that includes one copy of the hexamer repeat. Only the Moloney murine leukemia virus reverse transcriptase and its derivative Superscript I, carrying a deletion of the carboxy-terminal RNase H region, showed this response, indicating a template-switching mechanism different from one proposed that involves a RNase H-dependent strand transfer, Superscript II, however, which carries point mutations to reduce RNase H activity, does not cause a deletion. A possible mechanism involves the enzyme pausing at the 3' side of a stem-loop structure and the 3' end of the nascent DNA strand separating from the template and reannealing to the upstream hexamer repeat.

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A wide range of peptides produced from milk proteins have been demonstrated to produce a physiological response in model systems. These peptides may be released from intact proteins in the gastrointestinal tract by proteolytic digestion, but are also present in fermented products such as cheese and yogurt, as a result of the action of inherent proteases, such as plasmin, and/or bacterial proteases released by the starter culture. This study investigated the presence of peptides, previously reported to have bioactive properties, in commercially available yogurts and cheeses.

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Overcommitment of development capacity or development resource deficiencies are important problems in new product development (NPD). Existing approaches to development resource planning have largely neglected the issue of resource magnitude required for NPD. This research aims to fill the void by developing a simple higher-level aggregate model based on an intuitive idea: The number of new product families that a firm can effectively undertake is bound by the complexity of its products or systems and the total amount of resources allocated to NPD. This study examines three manufacturing companies to verify the proposed model. The empirical results confirm the study`s initial hypothesis: The more complex the product family, the smaller the number of product families that are launched per unit of revenue. Several suggestions and implications for managing NPD resources are discussed, such as how this study`s model can establish an upper limit for the capacity to develop and launch new product families.

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The object of this article is to estimate demand elasticities for a basket of staple food important for providing the caloric needs of Brazilian households. These elasticities are useful in the measurement of the impact of structural reforms on poverty. A two-stage demand system was constructed, based on data from Household Expenditure Surveys (POF) produced by IBGE (The Brazilian Bureau of Statistics) in 1987/88 and 1995/96. We have used panel data to estimate the model, and have calculated income, own-price, and cross-price elasticities for eight groups of goods and services and, in the second stage, for 11 sub groups of staple food products. We estimated those elasticities for the whole sample of consumers and for two income groups.

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A sensitive and precise stir bar sorptive extraction (SBSE) combined with LC (SBSE/LC) analysis is described for simultaneous determination of methyl, ethyl, propyl, and butyl parabens in commercial cosmetic products in agreement with the European Union Cosmetics Directive 76/768/EEC. Important factors in the optimization of SB SE efficiency are discussed, such as time and temperature of extraction, pH, and ionic strength of the sample, matrix effects, and liquid desorption conditions by different modes (magnetic stirring, ultrasonic). The LOQs of the SBSE/LC method ranged from 30 to 200 ng/mg, with linear response over a dynamic range, from the LOQ to 2.5 mu g/mg, with a coefficient of determination higher than 0.993. The interday precision of the SBSE/LC method presented a coefficient of variation lower than 5%. The effectiveness of the proposed method was proven for analysis of commercial cosmetic products such as body creams, antiperspirant creams, and sunscreens.

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Recently, conservationists have debated whether consumers of animal and plant potency products used to treat erectile dysfunction (ED) in traditional Chinese medicine (TCM) might be switching to Viagra, consequently consuming fewer of these animals and plants. To address this question, a survey examined the medical decisions of male consumers of TCM in Hong Kong who were over the age of 50. As predicted, these consumers reported selectively switching to Western medicines to treat ED, but not to treat other health ailments. These findings provide support for the possibility that Viagra may have conservation benefits for certain species.

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To date very Few families of critical sets for latin squares are known. The only previously known method for constructing critical sets involves taking a critical set which is known to satisfy certain strong initial conditions and using a doubling construction. This construction can be applied to the known critical sets in back circulant latin squares of even order. However, the doubling construction cannot be applied to critical sets in back circulant latin squares of odd order. In this paper a family of critical sets is identified for latin squares which are the product of the latin square of order 2 with a back circulant latin square of odd order. The proof that each element of the critical set is an essential part of the reconstruction process relies on the proof of the existence of a large number of latin interchanges.

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The products formed by a fructan:fructan fructosyltransferase (FFT) activity purified from Lolium rigidum Gaudin were identified after gas chromatography-mass spectrometry of partially methylated alditol acetates, electrospray ionization-mass spectrometry and reversed-phase high-performance liquid chromatography. The FFT activity synthesized oligofructans up to degree of polymerization (DP) 6, but did not synthesize fructans of DP > 6 even when assayed with (1,1,1)-kestopentaose for up to 10 h. The FFT activity when assayed with 1-kestose or 6(G)-kestose synthesized fructan with fructosyl residues almost exclusively linked by beta-2,1-glycosidic linkages. When assayed with 1-kestose, the FFT activity synthesized tetrasaccharides and pentasaccharides with an internal glucosyl residue. The predominant tetrasaccharide was (1&6(G))-kestotetraose and the predominant pentasaccharide was (1&6(G),1)-kestopentaose. By comparison, tetrasaccharides and pentasaccharides extracted from L. rigidum also contained predominantly beta-2,1-glycosidic linked fructans with an internal glucosyl residue. The only exception was that one of the pentasaccharides contained beta-2,1- and beta-2,6-glycosidic linked fructosyl residues. This pentasaccharide was not synthesized by the FFT activity. The role of this FFT activity in formation of oligofructans in L. rigidum is discussed.

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Objectives The first objective of this study was to evaluate the radiological impact on relatives and the environment because of outpatient treatment of differentiated thyroid carcinoma with 3.7 and 5.55 GBq of ((131)I)NaI. The second objective was to determine, analyze, and evaluate whole-body radiation dose to caregivers, the production of contaminated solid waste, and the potentiality of radiation dose and surface contamination existing inside patients` households. Methods Twenty patients were treated on an outpatient basis, taking into consideration their acceptable living conditions, interests, and willingness to comply with medical and radiation-safety guidelines. The caregivers themselves, as well as the potentiality of the radiation dose inside patients` residences, were monitored with a thermo-luminescence dosimeter. Surface contamination and contaminated solid wastes were identified and measured by using a Geiger-Muller detector. Results and discussion Twenty-six monitored individuals received accumulated effective radiation doses of less than 1.0 mSv, and only one 2.8 mSv, throughout the 7 days of measurement. The maximum registered value for the potential of radiation dose inside all living areas was 1.30 mSv. The monitored surface contamination inside patients` dwellings showed a mean value of 4.2 Bq/cm(2) for all surfaces found to be contaminated. A total of 2.5l of contaminated solid waste was generated by the patients with 3.33 MBq of all estimated activity. Conclusion This study revealed that the treatment of differentiated thyroid carcinoma with 3.7 and 5.55 GBq of ((131)I)NaI, on an outpatient basis, can be safe when overseen by qualified professionals and with an adapted radiation-protection guideline. Even considering the radioiodine activity level and the dosimetric methodology applied here, negligible human exposure and a nonmeasurable radiological impact to the human environment were found. Nucl Med Commun 30:533-541 (C) 2009 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

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The photodegradation of irinotecan (CPT-11), the semisynthetic derivative of the antitumor alkaloid 20(S)-camptothecin, has been investigated. The drug was exposed to laboratory light for up to 5 days in 0.9% saline solution (pH 8.5). Five significant photodegradation products were observed and a high-performance liquid chromatography (HPLC) assay was employed to isolate them from CPT-11 using gradient conditions. The structures were elucidated by nuclear magnetic resonance spectroscopy and tandem mass spectrometry and shown to be the result of extensive modifications of the lactone ring of CPT-11. Three of the compounds were found to belong to the mappicine group of alkaloids. In addition, the effect of light on the stability of CPT-11 in aqueous solutions and biological fluids was also assessed, Potassium phosphate buffers (0.05 M, pH 5.0-8.2) and saline, plasma, urine, and bile solutions containing 20 mu M CPT-11 were equilibrated in the dark for 24 h before being exposed to laboratory light for up to 171 h at ambient temperature. Four of the five identified photodegradation products were observed and quantitated by isocratic HPLC, using a different detection mode (fluorescence) than the one used for gradient elution, In general, CPT-11 was found to be unstable under neutral and alkaline conditions for all solutions investigated, with the exception of bile. We conclude that CPT-11 is photolabile and that care should be taken to protect samples, particularly those intended for the isolation and identification of novel metabolites of CPT-11.