998 resultados para Biochemical Activities


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Relatively simple techniques are now available which allow the preparation of large quantities of highly reproducible aggregate cultures from fetal rat brain or liver cells, and to grow them in a chemically defined medium. Since these cultures exhibit extensive histotypic cellular reorganization and maturation, they offer unique possibilities for developmental studies. Therefore, the purpose of the present study was to investigate the usefulness of these cultures in developmental toxicology. Aggregating brain cell cultures were exposed at different developmental stages to model drugs (i.e., antimitotic, neurotoxic, and teratogenic agents) and assayed for their responsiveness by measuring a set of biochemical parameters (i.e., total protein and DNA content, cell type-specific enzyme activities) which permit a monitoring of cellular growth and maturation. It was found that each test compound elicited a distinct, dose-dependent response pattern, which may ultimately serve to screen and classify toxic drugs by using mechanistic criteria. In addition, it could be shown that aggregating liver cell cultures are capable of toxic drug activation, and that they can be used in co-culture with brain cell aggregates, providing a potential model for complementary toxicological and metabolic studies.

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Tämän diplomityön tavoitteena oli selvittää arvoketjuanalyysin avulla toiminnot, joilla voittoatavoittelemattoman, julkisen osakeyhtiön toimintaa voitaisiin kuvata. Tarkoituksena oli selvittää mainitut toiminnot yleisesti ja luoda malli kohdeyrityksen arvoketjusta ja sen toiminnoista. Tutkielma jakautuu teoreettiseen ja empiiriseen osaan. Ensimmäinen pohjautuu aikaisempaan tutkimukseen ja kirjallisuuteen sidosryhmistä, arvon muodostumisesta ja arvoketjuanalyysistä. Jälkimmäinen on laadullista tapaustutkimusta. Empiriassa mallinnettiin Lappeenranta Innovation Oy:nsisäisiä toimintoja ja sidosryhmien odotuksia. Empiirinen tutkimus perustui kohdeyrityksen omistajille ja henkilöstölle tehtyihin haastatteluihin sekä yrityksen toiminnan päivittäiseen seurantaan. Johtopäätöksenätodettiin, että julkisen, voittoa tavoittelemattoman yrityksen toiminnot on mahdollista kuvata arvoketjuanalyysin avulla. Alan ja yrityksen asettamat erityispiirteet toivat haasteita määrittelylle, mutta silti arvoketju antoi selkeän tavan kohdeyrityksen toimintojen mallintamiselle.

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Novel alpha-mannosidase inhibitors of the type (2R,3R,4S)-2-({[(1R)-2-hydroxy-1-arylethyl]amino}methyl)pyrrolidine-3,4-diol have been prepared and assayed for their anticancer activities. Compound 30 with the aryl group=4-trifluoromethylbiphenyl inhibits the proliferation of primary cells and cell lines of different origins, irrespective of Bcl-2 expression levels, inducing a G2/Mcell cycle arrest and by modification of genes involved in cell cycle progression and survival.

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[eng] The group of teaching innovation in the area of Botany (GIBAF), University of Barcelona (UB), is raised each year to design new accreditation activities under continuous evaluation framework. We present the experience carried out during the academic year 2008-09 in the course of Pharmaceutical Botany. The aim has been to involve students for a semester in the authorship of a tutored project immediately useful and of easy permanence, beyond its assessment proving usefulness. The Medicinal Plants Garden of the Monastery of Pedralbes has been used as a resource and a collaboration agreement has been signed between the UB faculty and the Institute of Culture of Barcelona. The students have developed the work using the Moodle platform CampusvirtualUB into five stages which included preparation of files by students that have been modified in some steps following the various feedbacks from teachers. At the beginning of the activity, students were provided with a complete schedule of activities, the schedule for its implementation, and a total of 18 forced-use library resources. Finally, through Google sites, a website has been implemented, allowing for a virtual tour of the garden, documenting by referenced literature 50 medicinal plants for their nomenclature, botanical description, distribution, uses historical, current and future) and toxicity. The result of the activity was presented at a public ceremony in the Monastery of Pedralbes and is available at: http://sites.google.com/site/jardimedievalpedralbes/ [spa] El grupo de innovación docente integrado por profesores del área de Botánica (GIBAF) de la Universidad de Barcelona (UB) se plantea cada curso el diseño de nuevas actividades acreditativas en el marco de la evaluación continuada. Se presenta la experiencia llevada a cabo durante el curso 2008-09 en la asignatura Botánica Farmacéutica. El objetivo ha sido implicar durante un semestre a los estudiantes en la autoría de un proyecto tutorizado de inmediata utilidad y clara perdurabilidad, más allá de su utilidad acreditativa. Como recurso se ha utilizado el Jardín de Plantas Medicinales del Monasterio de Pedralbes y se ha firmado un convenio de colaboración docente entre la UB y el Instituto de Cultura de Barcelona. Los estudiantes han realizado el trabajo utilizando la plataforma Moodle del Campus virtual de la UB en cinco etapas que han incluido la confección de unas fichas que se han ido modificando en función de las diversas retroacciones de los profesores. Al inicio de la actividad, se facilitó a los estudiantes el cronograma completo de la actividad, la pauta para su realización, así como un total de 18 recursos bibliográficos de uso obligado. Finalmente, a través de GoogleSites, se ha realizado una web que permite realizar un paseo virtual por el jardín, documentando de forma referenciada para las 50 plantas medicinales su nomenclatura, descripción botánica, distribución, usos (históricos, actuales y futuros) y toxicidad. El resultado de la actividad fue presentado en un acto público en el Monasterio de Pedralbes y puede consultarse en: http://sites.google.com/site/jardimedievalpedralbes/

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The purpose of this study was to verify in man the relationships of muscle glycogen synthase and phosphorylase activities with glycogen concentration that were reported in animal studies. The upper level of glycogen concentration in muscle is known to be tightly controlled, and glycogen concentration was reported to have an inhibitory effect on synthase activity and a stimulatory effect on phosphorylase activity. Glycogen synthase and phosphorylase activity and glycogen concentration were measured in muscle biopsies in a group of nine normal subjects after stimulating an increase of their muscle glycogen concentration through either an intravenous glucose-insulin infusion to stimulate glycogen synthesis, or an Intralipid (Vitrum, Stockholm, Sweden) infusion in the basal state to inhibit glycogen mobilization by favoring lipid oxidation at the expense of glucose oxidation. Phosphorylase activity increased from 71.3 +/- 21.0 to 152.8 +/- 20.0 nmol/min/mg protein (P < .005) after the glucose-insulin infusion. Phosphorylase activity was positively correlated with glycogen concentration (P = .005 and P = .0001) after the glucose-insulin and Intralipid infusions, respectively. Insulin-stimulated glycogen synthase activity was significantly negatively correlated with glycogen concentration at the end of the Intralipid infusion (P < .005). In conclusion, by demonstrating a negative correlation of glycogen concentration with glycogen synthase and a positive correlation with phosphorylase, this study might confirm in man the double-feedback mechanism by which changes in glycogen concentration regulate glycogen synthase and phosphorylase activities. It suggests that this mechanism might play an important role in the regulation of glucose storage.

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In São Francisco Valley, Northeast Brazil, humic substances have been used by growers in fertigated fruit crops, due to its improvements on soil conditions and in plant nutrient uptake, metabolism and growth, reported from different growing places and crops. Nevertheless, little information about plant response to humic substance usage for local soil, weather and cropping system conditions is known. Hence, the metabolic response of guava tree during the orchard establishment to fertigation with humic substances and its correlation to the weather conditions were evaluated in Petrolina, State of Pernambuco. The treatments were manure application in soil combined with mineral fertilizers and humic substances applied through water of irrigation. The results showed that the fertigation treatments and plant age did not present conclusive effects in guava leaf contents of carbohydrates, proteins and amino acids. On the other side, the leaf contents of these compounds were influenced by the weather conditions.

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Spanish Cydia pomonella (L.) field populations have developed resistance to several insecticide groups. Diagnostic concentrations were established as the LC90 calculated on a susceptible strain (S_Spain) for five and seven insecticides and tested on eggs and neonate larvae field populations, respectively. The three most relevant enzymatic detoxification systems (mixed-function oxidases (MFO), glutathione S-tranferases (GST) and esterases (EST)) were studied for neonate larvae. In eggs, 96% of the field populations showed a significantly lower efficacy when compared with the susceptible strain (S_Spain) and the most effective insecticides were fenoxycarb and thiacloprid. In neonate larvae, a significant loss of susceptibility to the insecticides was detected. Flufenoxuron, azinphos-methyl and phosmet showed the lowest efficacy, while lambda-cyhalothrin, alpha-cypermethrin and chlorpyrifos-ethyl showed the highest. Biochemical assays showed that the most important enzymatic system involved in insecticide detoxification was MFO, with highest enzymatic activity ratios (5.1–16.6 for neonates from nine field populations). An enhanced GST and EST activities was detected in one field population, with enzymatic activity ratios of threefold and fivefold for GST and EST, respectively, when compared with the susceptible strain. The insecticide bioassays showed that the LC90 used were effective as diagnostic concentrations. Measures of MFO activity alongside bioassays with insecticide diagnostic concentrations could be used as tools for monitoring insecticide resistance in neonate larvae of C. pomonella.

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The present study evaluated the effects of modified atmosphere packaging on inhibition of the development of chilling injury symptoms in 'Douradão' peach after cold storage and the possible involvement of cell wall enzymes. Fruits were harvested at the middle stadium of ripening, packed in polypropylene trays and placed inside low density polyethylene (LDPE) bags (30, 50, 60 and 75 µm of thickness) with active modified atmosphere (10 kPa CO2 + 1.5 kPa O2, balance N2). The following treatments were tested: Control: peaches held in nonwrapped trays; MA30: LDPE film - 30 µm; MA50: LDPE film - 50 µm; MA60: LDPE film - 60 µm and MA75: LDPE film - 75 µm. Fruits were kept at 1±1ºC and 90±5% relative humidity (RH) for 28 days. After 14, 21 and 28 days, samples were withdrawn from MAP and kept in air at 25±1ºC and 90±5% RH for ripening. On the day of removal and after 4 days, peaches were evaluated for woolliness incidence, pectolytic enzymes activities. The respiratory rate and ethylene synthesis were monitored during 6 days of ripening. The results showed that MA50 and MA60 treatments had positive effect on the inhibition of the development of woolly texture and reduced pectin methylesterase activity on the ripe fruits, keeping good quality of 'Douradão' peach during 28 days of cold storage. The treatments Control, MA30 and MA75 showed higher woolliness incidence and did not present marketable conditions after 14 days of cold storage.

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Ruskeisiin kierrätysmassoihin kuuluu kulutuksen kannalta tärkeimpänä laatuna OCC (old corrugated containers). OCC sisältää noin 70-100% aaltopahvia eli pääasiassa se koostuu valkaisemattomasta kemiallisesta massasta. OCC uusiomassan ensisijainen käyttökohde on aaltopahvin valmistus. OCC:n kierrätyskuituprosessissa syntyy merkittäviä määriä rejektiä. Rejektin määrä riippuu paljolti kierrätettävän materiaalin laadusta ja puhtaudesta, mutta myös tulevan massan käyttötarkoituksesta sekä prosessiolosuhteista. OCC-prosessissa rejektoituvan aineksen määrä voi nousta korkeaksi, mikäli kierrätettävä materiaali sisältää märkälujaliimoja tai muuten raskaasti liimattuja komponentteja sekä runsaasti kontaminantteja, kuten muoveja, teippejä ja metalleja. Keskimäärin OCC-rejekti sisältää 30-60% kiinteää ainesta, 30-90% (kuivapaino) kuituja, 5-70% (kuivapaino) muoveja ja 1-10% (kuivapaino) tuhkaa. Syntynyt rejekti voidaan polttaa energiaksi tai käyttää maantäyttöaineena. Harvinaisempia sovelluksia rejektin käsittelyssä ovat rejektin kuitujen talteenotto uudelleenprosessointia varten tai alkoholin ja levuliinihapon tuottamiseen. Rejektin asianmukaisella käsittelyllä voidaan vähentää kaatopaikkakustannuksia, sekä parantaa kierrätysprosessin tuottavuutta. Tämän työn tarkoituksena oli tutkia biokemiallisen käsittelyn mahdollisuudet OCC-rejektin hajotuksessa. Alustavissa laboratoriomittakaavan kokeissa etsittiin sopiva käsittelytapa, joka toteutettiin sitten pilot plant -mittakaavassa. Tulokset osoittavat, että biokemiallisen käsittelyn avulla rejekti voidaan hajottaa jolloin jätteenkäsittelykustannukset pienenevät ja kierrätyskuituprosessin taloudellisuus paranee.

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The study of the reactivity of three 1-(2-dimethylaminoethyl)-1H-pyrazole derivatives of general formula [1-(CH2)2NMe2}-3,5-R2-pzol] {where pzol represents pyrazole and Rdouble bond; length as m-dashH (1a), Me (1b) or Ph (1c)} with [MCl2(DMSO)2] (Mdouble bond; length as m-dashPt or Pd) under different experimental conditions allowed us to isolate and characterize cis-[M{κ2-N,N′-{[1-(CH2)2NMe2}-3,5-R2-pzol])}Cl2] {MMdouble bond; length as m-dashPtPt (2a-2c) or Pd (3a-3c)} and two cyclometallated complexes [M{κ3-C,N,N′-{[1-(CH2)2NMe2}-3-(C5H4)-5-Ph-pzol])}Cl] {Mdouble bond; length as m-dashPt(II) (4c) or Pd(II) (5c)}. Compounds 4c and 5c arise from the orthometallation of the 3-phenyl ring of ligand 1c. Complex 2a has been further characterized by X-ray crystallography. Ligands and complexes were evaluated for their in vitro antimalarial against Plasmodium falciparum and cytotoxic activities against lung (A549) and breast (MDA MB231 and MCF7) cancer cellular lines. Complexes 2a-2c and 5c exhibited only moderate antimalarial activities against two P. falciparum strains (3D7 and W2). Interestingly, cytotoxicity assays revealed that the platinacycle 4c exhibits a higher toxicity than cisplatin in the three human cell lines and that the complex 2a presents a remarkable cytotoxicity and selectivity in lung (IC50 = 3 μM) versus breast cancer cell lines (IC50 > 20 μM). Thus, complexes 2c and 4c appear to be promising leads, creating a novel family of anticancer agents. Electrophoretic DNA migration studies in presence of the synthesized compounds have been performed, in order to get further insights into their mechanism of action.

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Soybean (Glycine max. L.) nodular senescence results in the dismantling of the peribacteroid membrane (PBM) and in an increase of soybean isocitrate lyase (ICL; EC 4.1.3.1) and malate synthase (MS; EC 4.1.3.2) mRNA and protein levels. This suggests that in senescing soybean nodular cells, the specific glyoxylate cycle enzyme activities might be induced to reallocate carbon obtained from the PBM degradation. In order to evaluate as well the carbon metabolism of the nitrogen-fixing Bradyrhizobium japonicum endosymbiotic bacteroids during nodular senescence, their glyoxylate cycle activities were also investigated. To this end, partial DNA sequences were isolated from their icl and ms genes, but the corresponding mRNAs were not detected in the microorganisms. It was also observed that the bacteroid ICL and MS activities were negligible during nodular senescence. This suggests that glyoxylate cycle activities are not reinitiated in the bacteroids under these physiological conditions. In case the microorganisms nevertheless feed on the PBM degradation products, this might occur via the citric acid cycle exclusively.