956 resultados para tRNA modifying enzymes
Resumo:
We have synthesized a family of rheinhuprine hybrids to hit several key targets for Alzheimer"s disease. Biological screening performed in vitro and in Escherichia coli cells has shown that these hybrids exhibit potent inhibitory activities against human acetylcholinesterase butyrylcholinesterase, and BACE-1, dual Aβ42 and tau anti-aggregating activity, and brain permeability. Ex vivo studies with the leads (+)- and ()-7e in brain slices of C57bl6 mice have revealed that they efficiently protect against the Aβ-induced synaptic dysfunction , preventing the loss of synaptic proteins and/or have a positive effect on the induction of long term potentiation. In vivo studies in APP-PS1 transgenic mice treated i.p. for 4 weeks with (+)- and ()-7e have shown a central soluble Aβ lowering effect, accompanied by an increase in the levels of mature amyloid precursor protein (APP). Thus, (+)- and ()-7e emerge as very promising disease-modifying anti-Alzheimer drug candidates.
Resumo:
We have synthesized a family of rheinhuprine hybrids to hit several key targets for Alzheimer"s disease. Biological screening performed in vitro and in Escherichia coli cells has shown that these hybrids exhibit potent inhibitory activities against human acetylcholinesterase butyrylcholinesterase, and BACE-1, dual Aβ42 and tau anti-aggregating activity, and brain permeability. Ex vivo studies with the leads (+)- and ()-7e in brain slices of C57bl6 mice have revealed that they efficiently protect against the Aβ-induced synaptic dysfunction , preventing the loss of synaptic proteins and/or have a positive effect on the induction of long term potentiation. In vivo studies in APP-PS1 transgenic mice treated i.p. for 4 weeks with (+)- and ()-7e have shown a central soluble Aβ lowering effect, accompanied by an increase in the levels of mature amyloid precursor protein (APP). Thus, (+)- and ()-7e emerge as very promising disease-modifying anti-Alzheimer drug candidates.
Resumo:
Yeast cells contain a family of three monothiol glutaredoxins: Grx3, 4, and 5. Absence of Grx5 leads to constitutive oxidative damage, exacerbating that caused by external oxidants. Phenotypic defects associated with the absence of Grx5 are suppressed by overexpression ofSSQ1 and ISA2, two genes involved in the synthesis and assembly of iron/sulfur clusters into proteins. Grx5 localizes at the mitochondrial matrix, like other proteins involved in the synthesis of these clusters, and the mature form lacks the first 29 amino acids of the translation product. Absence of Grx5 causes: 1) iron accumulation in the cell, which in turn could promote oxidative damage, and 2) inactivation of enzymes requiring iron/sulfur clusters for their activity. Reduction of iron levels in grx5 null mutants does not restore the activity of iron/sulfur enzymes, and cell growth defects are not suppressed in anaerobiosis or in the presence of disulfide reductants. Hence, Grx5 forms part of the mitochondrial machinery involved in the synthesis and assembly of iron/sulfur centers.
Resumo:
Factors modifying drug and placebo responses in randomized trials for bipolar mania. Yildiz A, Vieta E, Tohen M, Baldessarini RJ. Source Department of Psychiatry, Dokuz Eylül University, Izmir, Turkey. agul_yildiz@hotmail.com Abstract Randomized placebo-controlled trials (RCTs) are standard for assessing efficacy and safety of treatments. We pursued preliminary indications that some factors are associated differentially with responses to placebo or drugs in RCTs for bipolar mania. We meta-analysed data from RCTs to assess influences of study-site count, subjects' age, sex distribution, diagnostic subgroups, clinical features, trial-completion rates, and publication year on mean difference (MD) in mania ratings between intake and final assessments. In 38 RCTs involving 3812 placebo-treated and 6988 drug-treated patients, symptomatic improvement was similar in placebo arms of trials of effective (6.77, 95% CI 5.77-7.76) and ineffective (7.61, 95% CI 5.47-8.75) drugs. Lesser placebo responses (MD) and greater drug-placebo differences (Hedges' g) were associated with fewer study sites, younger patients' age, and male sex. More patients with initial psychotic features and more trial completion in drug arms were associated with greater drug-associated improvement (MD) and drug-placebo contrast (Hedges' g), whereas more mixed-state diagnoses decreased both measures. Identifying modifying factors can support more efficient and cost-effective designs of therapeutic trials. In trials for mania, fewer sites may limit placebo response and enhance drug-placebo contrasts.
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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.
Resumo:
Työn tavoitteena oli kehittää mikro-organismeja kestävä suoli eli makkarankuori. Työ suoritettiin modifioimalla regeneroitua selluloosaa. Modifiointiliuoksena käytettiin etikkahapon ja etikkahappoanhydridin seosta, johon lisättiin rikkihappoa katalyytiksi. Työssä etsittiin parasta yhdistelmää, joka koostui modifiointiradannopeudesta, modifiointiliuoskoostumuksesta ja erilaisista modifiointimenetelmistä. Kirjallisuusosassa käsiteltiin yleisesti asetaattikalvoja, niiden valmistusta ja ominaisuuksia. Lisäksi perehdyttiin entsyymin ominaisuuksiin ja toimintaan yleisesti. Entsyymeistä yksi otettiin lähempään tarkasteluun. Kokeissa regeneroitua selluloosaa modifioitiin liuoksessa, jonka koostumusta muunneltiin. Kokeissa oli kolme erilaista modifiointimenetelmää, joissa käytettiin neljää modifiointiliuoskoostumusta ja kolmea modifiointinopeutta. Mittauksissa tutkittiin modifioinnin vaikutusta suoliin verrattuna normaaleihin suoliin. Suolille tehtiin sekä mekaanisia että kemiallisia testejä. Kemiallisista testeistä tärkein oli testi, jossa modifioitu suoli altistettiin mikro-organismille. Tulosten perusteella valittiin paras menetelmä. Työssä havaittiin yhden menetelmän olevan muita paljon parempi. Tällä menetelmällä suoritettiin toistokokeita, jotka varmistivat jo saatuja tuloksia. Liuoskoostumusten välillä ei ollut suuria eroja, mutta kuitenkin niistä yksi osoittautui parhaimmaksi. Nopeutta oli vaikeampi määrittää, mutta siitäkin saatiin määritettyä tietty haarukka, jossa reaktio oli tehokkain.
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Background: Epidemiological studies suggest that coffee consumption reduces the risk of cancer, but the molecular mechanisms of its chemopreventive effects remain unknown. Objective: To identify differentially expressed genes upon incubation of HT29 colon cancer cells with instant caffeinated coffee (ICC) or caffeic acid (CA) using whole genome microarrays. Results: ICC incubation of HT29 cells caused the overexpression of 57 genes and the underexpression of 161, while CA incubation induced the overexpression of 12 genes and the underexpression of 32. Using Venn-Diagrams, we built a list of five overexpressed genes and twelve underexpressed genes in common between the two experimental conditions. This list was used to generate a biological association network in which STAT5B and ATF-2 appeared as highly interconnected nodes. STAT5B overexpression was confirmed at the mRNA and protein levels. For ATF-2, the changes in mRNA levels were confirmed for both ICC and CA, whereas the decrease in protein levels was only observed in CA-treated cells. The levels of cyclin D1, a target gene for both STAT5B and ATF-2, were dowregulated by CA in colon cancer cells and by ICC and CA in breast cancer cells. Conclusions: Coffee polyphenols are able to affect cyclin D1 expression in cancer cells through the modulation of STAT5B and ATF-2.
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Tämä työ tehtiin globaaliin elektroniikka-alan yritykseen. Diplomityö liittyy haasteeseen, jonka lisääntynyt globalisaatio ja kiristyvä kilpailu ovat luoneet: case yrityksen on selvitettävä kuinka se voi saavuttaa kasvutavoitteet myös tulevaisuudessa hankkimalla uusia asiakkaita ja olemalla yhä enenevissä määrin maailmanlaajuisesti läsnä. Tutkimuksen tavoite oli löytää sopiva malli potentiaalisten avainasiakkaiden identifiointiin ja valintaan, sekä testata ja modifioida valittua mallia case yrityksen tarpeiden mukaisesti. Erityisesti raakadatan kerääminen, asiakkaiden houkuttelevuuskriteerit ja kohdemarkkinarako olivat asioita, jotka tarvitsivat tutkimuksessa huomiota. Kirjallisuuskatsauksessa keskityttiin yritysmarkkinoihin, eri asiakassuhteenhallinnan lähestymistapoihin ja avainasiakkaiden määrittämiseen. CRM:n, KAM:n ja Customer Insight-ajattelun perusteet esiteltiin yhdessä eri avainasiakkaiden identifiointimallien kanssa. Valittua Chevertonin mallia testattiin ja muokattiin työn empiirisessä osassa. Tutkimuksen empiirinen kontribuutio on modifioitu malli potentiaalisten avainasiakkaiden identifiointiin. Se auttaa päätöksentekijöitä etenemään systemaattisesti ja organisoidusti askel askeleelta kohti potentiaalisten asiakkaiden listaa tietyltä markkina-alueelta. Työ tarjoaa työkalun tähän prosessiin sekä luo pohjaa tulevaisuuden tutkimukselle ja toimenpiteille.
Resumo:
The response of the common carp to diets with varying amounts of digestible starch, provided either as pea meal (LP, HP, 30 and 46% peas, respectively) or as cereal (LW, HW, 30 and 46% wheat, respectively), was studied and compared with the response to a carbohydrate-free protein-rich diet (CF). Here we focused on the utilisation of dietary carbohydrates by examining the relationship between dietary starch intake, hepatic hexokinase activities, circulating insulin and muscle insulin receptor system. Plasma glucose concentration and hepatic high Km hexokinase (glucokinase, GK) activity were not affected by the content of digestible starch, but 6 h after feeding enzyme activity was higher in the fish fed carbohydrate diets. Similarly, low Km hexokinase (HK) activity was also higher in the fish 24 h after feeding. Fat gain and protein retention were significantly improved by increased digestible starch intake, especially in the HP group, which in turn, presented the highest plasma insulin levels. Glycogen stores were moderately increased by the ingestion of digestible starch. The number of insulin receptors was greater in the CF group than in fish on carbohydrates, except the HP group. Our results confirmed that the common carp uses dietary carbohydrates efficiently, especially when there are provided by peas. This efficiency might be related to the enhanced response of postprandial insulin observed in the HP group.