959 resultados para disinfection by-product
Resumo:
OBJECTIVES: The diagnosis of pheochromocytoma relies on the measurement of plasma free metanephrines assay whose reliability has been considerably improved by ultra-high pressure liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Here we report an analytical interference occurring between 4-hydroxy-3-methoxymethamphetamine (HMMA), a metabolite of 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy"), and normetanephrine (NMN) since they share a common pharmacophore resulting in the same product ion after fragmentation. DESIGN AND METHODS: Synthetic HMMA was spiked into plasma samples containing various concentrations of NMN and the intensity of the interference was determined by UPLC-MS/MS before and after improvement of the analytical method. RESULTS: Using a careful adjustment of chromatographic conditions including the change of the UPLC analytical column, we were able to distinguish both compounds. HMMA interference for NMN determination should be seriously considered since MDMA activates the sympathetic nervous system and if confounded with NMN may lead to false-positive tests when performing a differential diagnostic of pheochromocytoma.
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The prescription information (summary of product characteristics, SPC) is compiled by the pharmaceutical industry as required by the national regulatory authorities. They vary in their content about the properties of drugs and about the usefulness of therapeutic drug monitoring (TDM) in the blood of patients. Based on a previous study carried out in Germany, the degree of agreement of French SPC for 59 psychotropic drugs with the existing medico-scientific evidence in the area of TDM was examined using a recently developed instrument. A summary score of SPC content (SPCC) related to TDM (SPCC(TDM)) has been calculated and compared with the level of recommendation of TDM of the AGNP-TDM expert group consensus guidelines for TDM in psychiatry [AGNP: Arbeitsgemeinschaft für Neuropsychopharmakologie und Pharmakopsychiatrie (Association for neuropsychopharmacology and pharmacopsychiatry)]. Among the antidepressants, antipsychotics, tranquillizers/hypnotic agents and mood stabilizers, the highest SPCC(TDM) scores in the French SPC were reached for imipramine (16), haloperidol (6), clonazepam (8) and lithium (23), respectively. Results were similar to those obtained from the analysis of German SPC, and considerable disagreement was found between the information on TDM in SPC and existing medico-scientific evidence, albeit less in the case of mood stabilizers. Taking into account the recommendations of the AGNP-TDM expert group guidelines, there is a deficit in the French SPC concerning TDM-relevant information. An amelioration of this situation could help to improve the clinical practice of TDM of psychotropic drugs, as the SPC is a widely used tool.
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Salicylic acid (SA) plays a central role as a signalling molecule involved in plant defense against microbial attack. Genetic manipulation of SA biosynthesis may therefore help to generate plants that are more disease-resistant. By fusing the two bacterial genes pchA and pchB from Pseudomonas aeruginosa, which encode isochorismate synthase and isochorismate pyruvate-lyase, respectively, we have engineered a novel hybrid enzyme with salicylate synthase (SAS) activity. The pchB-A fusion was expressed in Arabidopsis thaliana under the control of the constitutive cauliflower mosaic virus (CaMV) 35S promoter, with targeting of the gene product either to the cytosol (c-SAS plants) or to the chloroplast (p-SAS plants). In p-SAS plants, the amount of free and conjugated SA was increased more than 20-fold above wild type (WT) level, indicating that SAS is functional in Arabidopsis. P-SAS plants showed a strongly dwarfed phenotype and produced very few seeds. Dwarfism could be caused by the high SA levels per se or, perhaps more likely, by a depletion of the chorismate or isochorismate pools of the chloroplast. Targeting of SAS to the cytosol caused a slight increase in free SA and a significant threefold increase in conjugated SA, probably reflecting limited chorismate availability in this compartment. Although this modest increase in total SA content did not strongly induce the resistance marker PR-1, it resulted nevertheless in enhanced disease resistance towards a virulent isolate of Peronospora parasitica. Increased resistance of c-SAS lines was paralleled with reduced seed production. Taken together, these results illustrate that SAS is a potent tool for the manipulation of SA levels in plants.
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The demonstration of beneficial effects of cell therapy despite the persistence of only few transplanted cells in vivo suggests secreted factors may be the active component of this treatment. This so-called paracrine hypothesis is supported by observations that culture media conditioned by progenitor cells contain growth factors that mediate proangiogenic and cytoprotective effects. Cardiac progenitor cells in semi-suspension culture form spherical clusters (cardiospheres) that deliver paracrine signals to neighboring cells. A key component of paracrine secretion is exosomes, membrane vesicles that are stored intracellularly in endosomal compartments and are secreted when these structures fuse with the cell plasma membrane. Exosomes have been identified as the active component of proangiogenic effects of bone marrow CD34(+) stem cells in mice and the regenerative effects of embryonic mesenchymal stem cells in infarcted hearts in pigs and mice. Here, we provide electron microscopic evidence of exosome secretion by progenitor cells in mouse myocardium and human cardiospheres. Exosomes are emerging as an attractive vector of paracrine signals delivered by progenitor cells. They can be stored as an "off-the-shelf" product. As such, exosomes have the potential for circumventing many of the limitations of viable cells for therapeutic applications in regenerative medicine.
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Access to new biological sources is a key element of natural product research. A particularly large number of biologically active molecules have been found to originate from microorganisms. Very recently, the use of fungal co-culture to activate the silent genes involved in metabolite biosynthesis was found to be a successful method for the induction of new compounds. However, the detection and identification of the induced metabolites in the confrontation zone where fungi interact remain very challenging. To tackle this issue, a high-throughput UHPLC-TOF-MS-based metabolomic approach has been developed for the screening of fungal co-cultures in solid media at the petri dish level. The metabolites that were overexpressed because of fungal interactions were highlighted by comparing the LC-MS data obtained from the co-cultures and their corresponding mono-cultures. This comparison was achieved by subjecting automatically generated peak lists to statistical treatments. This strategy has been applied to more than 600 co-culture experiments that mainly involved fungal strains from the Fusarium genera, although experiments were also completed with a selection of several other filamentous fungi. This strategy was found to provide satisfactory repeatability and was used to detect the biomarkers of fungal induction in a large panel of filamentous fungi. This study demonstrates that co-culture results in consistent induction of potentially new metabolites.
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We have shown that indels in gp120 V4 are associated to the presence of duplicated and palindromic sequences, suggesting that they may be produced by strand-slippage misalignment mechanism. Indels in V4 involved region-specific duplications 9 to 15 bp long, and repeats of various lengths, associated to trinucleotides AAT. No duplications were found in V3 and C3. The frequency of palindromic sequences in individual genes was found to be significantly higher in gp120 (p < or = 3.00E-7), and significantly lower in Tat (p < or = 9.00E-7) than the average frequency calculated over the full genome. The finding of elements of misalignment in association with indels in V4 suggests that these mutations may occur in proviral DNA after integration of HIV into the host genome. It also implies that occurrence of large indels in gp120 is not random but is directed by the presence and distribution of elements of misalignment in the HIV genome.
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This work presents geochemistry and structural geology data concerning the low enthalpy geothermal circuits of the Argentera crystalline Massif in northwestern Italian Alps. I n this area some thermal springs (50-60 degreesC), located in the small Bagni di Vinadio village, discharge mixtures made up of a Na-Cl end-member and a Na-SO4 component. The latter is also discharged by the thermal springs of Terme di Valdieri located some kilometres apart within the same tectonic complex. Both end-members share the same meteoric origin and the same reservoir temperature, which is close to 150 degreesC. Explanations are thus required to understand how they reach the surface and how waters of the same origin and circulating in similar rocks can attain such different compositions. Sodium-sulphate waters discharged at both sites, likely represent the common interaction product of meteoric waters with the widespread granitic-migmatitic rocks of the Argentera Massif, whereas Na-CI waters originate through leaching of mineralised cataclastic rocks, which are rich in phyllosilicatic minerals and fluid inclusions, both acting as Cl- sources. Due to the relatively low inferred geothermal gradient of the region, -25C/km, meteoric waters have to descend to depths of 5.5-6 km to attain temperatures of similar to 150 degreesC. These relevant depths can be reached by descending meteoric waters, due to the recent extensional stress field, which allows the development of geothermal circulations at greater depths than in other sectors of the Alps by favouring a greater fractures aperture. The ascent of the thermal waters rakes place along brittle shear zones. In both sites, the thermal waters emerge at the bottoms of the valleys, close to either the lateral termination of a brittle shear zone at Terme di Valdieri, or a step-over between two en-echelon brittle shear zones at Bagni di Vinadio. These observations attest to a strong control operated on the location of outlet regions by both brittle tectonics and the minima in hydraulic potential inside the fractured massif.
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The SeDeM Diagram Expert System has been used to study excipients, Captopril and designed formulations for their galenic characterization and to ascertain the critical points of the formula affecting product quality to obtain suitable formulations of Captopril Direct Compression SR Matrix Tablets. The application of the Sedem Diagram Expert System enables selecting excipients with in order to optimize the formula in the preformulation and formulation studies. The methodology is based on the implementation of ICH Q8, establishing the design space of the formula with the use of experiment design, using the parameters of the SeDeM Diagram Expert System as system responses.
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Raman spectroscopy combined with chemometrics has recently become a widespread technique for the analysis of pharmaceutical solid forms. The application presented in this paper is the investigation of counterfeit medicines. This increasingly serious issue involves networks that are an integral part of industrialized organized crime. Efficient analytical tools are consequently required to fight against it. Quick and reliable authentication means are needed to allow the deployment of measures from the company and the authorities. For this purpose a method in two steps has been implemented here. The first step enables the identification of pharmaceutical tablets and capsules and the detection of their counterfeits. A nonlinear classification method, the Support Vector Machines (SVM), is computed together with a correlation with the database and the detection of Active Pharmaceutical Ingredient (API) peaks in the suspect product. If a counterfeit is detected, the second step allows its chemical profiling among former counterfeits in a forensic intelligence perspective. For this second step a classification based on Principal Component Analysis (PCA) and correlation distance measurements is applied to the Raman spectra of the counterfeits.
Resumo:
Background: To determine whether misalignment structures such as duplications, repeats, and palindromes are associated to insertions/deletions (indels) in gp120, indicating that indels are indeed frameshift mutations generated by DNA misalignment mechanism. Methods: Cloning and sequencing of a fragment of HIV-1 gp120 spanning C2-C4 derived from plasma RNA in 12 patients with early chronic disease and naïve to antiretroviral therapy. Results: Indels in V4 involved always insertion and deletion of duplicated nucleotide segments, and AAT repeats, and were associated to the presence of palindromic sequences. No duplications were detected in V3 and C3. Palindromic sequences occurred with similar frequencies in V3, C3 and V4; the frequency of palindromes in individual genes was found to be significantly higher in structural (gp120, p ≤ 3.00E-7) and significantly lower in regulatory (Tat, p ≤ 9.00E-7) genes, as compared to the average frequency calculated over the full genome. Discussion: Indels in V4 are associated to misalignment structures (i.e. duplications repeat and palindromes) indicating DNA misalignment as the mechanism underlying length variation in V4. The finding that indels in V4 are caused by DNA misalignment has some very important implications: 1) indels in V4 are likely to occur in proviral DNA (and not in RNA), after integration of HIV into the host genome; 2) they are likely to occur as progressive modifications of the early founder virus during chronic infection, as more and more cells get infected; 3) frameshift mutations involving any number of base pairs are likely to occur evenly across gp120; however, only those mutants carrying a functional gp120 (indels as multiples of three base pairs) will be able to perpetuate the virus cycle and to keep spreading through the population.
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A nationwide investigation was conducted in Switzerland to establish the exposure of the population by medical x rays and update the results of the 1998 survey. Both the frequency and the dose variations were studied in order to determine the change in the collective dose. The frequency study addressed 206 general practitioners (GPs), 30 hospitals, and 10 private radiology institutes. Except for the latter, the response rate was very satisfactory. The dose study relied on the assessment of the speed class of the screen-film combinations used by the GPs as well as the results of two separate studies dedicated to fluoroscopy and CT. The investigation showed that the total number of all medical x-ray examinations performed by GPs registered a 1% decrease between 1998 and 2003, and that the sensitivities of the film-screen combinations registered a shift towards higher values, leading to a reduction of the dose delivered by a GP of the order of 20%. The study indicated also that the total number of all x-ray examinations performed in hospitals increased by 4%, with a slight increase of radiographies by 1% but significant decrease of examinations involving fluoroscopy (39%), and a 70% increase for CT examinations. Concerning the doses, the investigation of a selection of examinations involving fluoroscopy showed a significant increase of the kerma-area product (KAP) per procedure. For CT the study showed an increase of the dose-length product (DLP) per procedure for skull and abdomen examinations, and a decrease for chest examination. Both changes in the frequency and the effective dose per examination led to a 20% increase in the total collective dose.
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A new coding technique to be used in steganography is evaluated. The performanceof this new technique is computed and comparisons with the well-known theoreticalupper bound, Hamming upper bound and basic LSB are established.
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Diplomityön tavoitteena on rakentaa malli kohdeyrityksen yhden strategisen liiketoimintayksikön tuoteryhmänkohtaisten kannattavuuksien selvittämiseksi yli kokotoimitusketjun. Työssä on keskitytty vain välillisiin kustannuksiin ja välittömien kustannusten osalta on luotettu toiminnanohjausjärjestelmän antamiin tietoihin. Työn lähtökohtana ja teoreettisena viitekehikkona on toimintoperustainen kustannuslaskenta, jonka periaatteita noudattaen kannattavuusmalli rakennettiin. Mallin periaatteet on esitetty työssä mutta sen tuottamia tuloksia ei ole syvemmin analysoitu. Ongelma osoittautui haasteelliseksi ja tulosten verifiointi lähes mahdottomaksi käytettyjen subjektiivisten arvioiden ja ennalta odottamattomien välittömien tuotekustannusten suurten virheiden vuoksi. Työn johtopäätöksissä keskitytään sisäisen laskentatoimen kulttuurin kehittämiseen tuotekustannuslaskennan ja yleisen kustannusvalvonnan näkökulmasta kohdeyrityksessä.
Resumo:
Verkostoitunut kansainvälinen tuotekehitys on tärkeä osa menestystä nykypäivän muuttuvassa yritysmaailmassa. Toimintojen tehostamiseksi myös projektitoiminnot on sopeutettava kansainväliseen toimintaympäristöön. Kilpailukyvyn säilyttämiseksi projektitoimintoja on lisäksi jatkuvasti tehostettava. Yhtenäkeinona nähdään projektioppiminen, jota voidaan edistää monin eri tavoin. Tässätyössä keskitytään projektitiedonhallinnan kehittämisen tuomiin oppimismahdollisuuksiin. Kirjallisuudessa kerrotaan, että projektitiedon jakaminen ja sen hyödyntäminen seuraavissa projekteissa on eräs projektioppimisen edellytyksistä. Tämäon otettu keskeiseksi näkökulmaksi tässä tutkimuksessa. Lisäksi tutkimusalueen rajaamiseksi työ tarkastelee erityisesti projektioppimista kansainvälisten tuotekehitysprojektien välillä. Työn tavoitteena on esitellä keskeisiä projektioppimisen haasteita ja etsiä konkreettinen ratkaisu vastaamaan näihin haasteisiin. Tuotekehitystoiminnot ja kansainvälinen hajautettu projektiorganisaatio kohtaavat lisäksi erityisiä haasteita, kuten tiedon hajautuneisuus, projektihenkilöstön vaihtuvuus, tiedon luottamuksellisuus ja maantieteelliset haasteet (esim. aikavyöhykkeet ja toimipisteen sijainti). Nämä erityishaasteet on otettu huomioon ratkaisua etsittäessä. Haasteisiin päädyttiin vastaamaan tietotekniikkapohjaisella ratkaisulla, joka suunniteltiin erityisesti huomioiden esimerkkiorganisaation tarpeet ja haasteet. Työssä tarkastellaan suunnitellun ratkaisun vaikutusta projektioppimiseen ja kuinka se vastaa havaittuihin haasteisiin. Tuloksissa huomattiin, että projektioppimista tapahtui, vaikka oppimista oli vaikea suoranaisesti huomata tutkimusorganisaation jäsenten keskuudessa. Projektioppimista voidaan kuitenkin sanoa tapahtuvan, jos projektitieto on helposti koko projektiryhmän saatavilla ja se on hyvin järjesteltyä. Muun muassa nämä ehdot täyttyivät. Projektioppiminen nähdään yleisesti haastavana kehitysalueena esimerkkiorganisaatiossa. Suuri osa tietämyksestä on niin sanottua hiljaistatietoa, jota on hankala tai mahdoton saattaa kirjalliseen muotoon. Näin olleen tiedon siirtäminen jää suurelta osin henkilökohtaisen vuorovaikutuksen varaan. Siitä huolimatta projektioppimista on mahdollista kehittää erilaisin toimintamallein ja menetelmin. Kehitys vaatii kuitenkin resursseja, pitkäjänteisyyttä ja aikaa. Monet muutokset voivat vaatia myös organisaatiokulttuurin muutoksen ja vaikuttamista organisaation jäseniin. Motivaatio, positiiviset mielikuvat ja selkeät strategiset tavoitteet luovat vakaan pohjan projektioppimisen kehittämiselle.
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Diplomityön tavoitteena oli selvittää, kuinka kohdeyrityksessä nykyhetkellä pitkältiräätälöitynä tuotetut putkilämmönvaihtimet voitaisiin standardisoida, jotta pystyttäisiin kohdistamaan resursseja oikein ja parantamaan siten yrityksen taloudellista suorituskykyä. Tutkimuksen edetessä määräävimmäksi tekijäksi työn tuloksia ajatellen nousi taloudellinen standardisointiaste, jonka perusteeksi kohdeyrityksen putkilämmönvaihtimissa valittiin standardisoitu suunnitteluohjeisto. Suunnitteluohjeiston lisäksi tuotestandardiin liitettiin ehdotus toimintapojen automatisoimisesta parametrisen valintataulukon sekä sähköisen manuaalin avulla. Työssä tuotestandardisointia tarkastellaan rationalisointi-investointina ja sen kannattavuutta on tarkasteltu investointilaskelmien sekä herkkyys analyysin avulla. Alkuarvot investointilaskelmissa perustuvat työssä yhdelle putkilämmönvaihtimelletoteutettuun tuotestandardisointitapaan, jos tätä tapaa käytettäisiin jatkossa kaikkiin kyseisen yksikön putkilämmönvaihtimiin.