857 resultados para Phase-ii Trial


Relevância:

80.00% 80.00%

Publicador:

Resumo:

A reduced cancer risk associated with fruit and vegetable phytochemicals initially dictated chemopreventive approaches focused on specific green variety consumption or even single nutrient supplementations. However, these strategies not only failed to provide any health benefits but gave rise to detrimental effects. In parallel, public-health chemoprevention programmes were developed in the USA and Europe to increase whole vegetable consumption. Among these, the National Cancer Institute (NCI) sponsored plan “5 to 9 a day for a better health” was one of the most popular. This campaign promoted wide food choice through the consumption of at least 5 to 9 servings a day of colourful fruits and vegetables. In this study the effects of the diet suggested by NCI on transcription, translation and catalytic activity of both xenobiotic metabolizing (XME) and antioxidant enzymes were studied in the animal model. In fact, the boost of both antioxidant defences and “good” phase-II together with down-regulation of “bad” phase-I XMEs is still considered one of the most widely-used strategies of cancer control. Six male Sprague Dawley rats for each treatment group were used. According to the Italian Society of Human Nutrition, a serving of fruit, vegetables and leafy greens corresponds to 150, 250 and 50 g, respectively, in a 70 kg man. Proportionally, rats received one or five servings of lyophilized onion, tomato, peach, black grape or lettuce – for white, red, yellow, violet or green diet, respectively - or five servings of each green (“5 a day” diet) by oral gavage daily for 10 consecutive days. Liver subcellular fractions were tested for various cytochrome P450 (CYP) linked-monooxygenases, phase-II supported XMEs such as glutathione S-transferase (GST) and UDP-glucuronosyl transferase (UDPGT) as well as for some antioxidant enzymes. Hepatic transcriptional and translational effects were evaluated by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analysis, respectively. dROMs test was used to measure plasmatic oxidative stress. Routine haematochemical parameters were also monitored. While the five servings administration didn’t significantly vary XME catalytic activity, the lower dose caused a complex pattern of CYP inactivation with lettuce exerting particularly strong effects (a loss of up to 43% and 45% for CYP content and CYP2B1/2-linked XME, respectively; P<0.01). “5 a day” supplementation produced the most pronounced modulations (a loss of up to 60% for CYP2E1-linked XME and a reduction of CYP content of 54%; P<0.01). Testosterone hydroxylase activity confirmed these results. RT-PCR and Western blot analysis revealed that the “5 a day” diet XMEs inactivations were a result of both a transcriptional and a translational effect while lettuce didn’t exert such effects. All administrations brought out none or fewer modulation of phase-II supported XMEs. Apart from “5 a day” supplementation and the single serving of lettuce, which strongly induced DT- diaphorase (an increase of up to 141 and 171%, respectively; P<0.01), antioxidant enzymes were not significantly changed. RT-PCR analysis confirmed DT-diaphorase induction brought about by the administration of both “5 a day” diet and a single serving of lettuce. Furthermore, it unmasked a similar result for heme-oxygenase. dROMs test provided insight into a condition of high systemic oxidative stress as a consequence of animal diet supplementation with “5 a day” diet and a single serving of lettuce (an increase of up to 600% and 900%, respectively; P<0.01). Haematochemical parameters were mildly affected by such dietary manipulations. According to the classical chemopreventive theory, these results could be of particular relevance. In fact, even if antioxidant enzymes were only mildly affected, the phase-I inactivating ability of these vegetables would be a worthy strategy to cancer control. However, the recorded systemic considerable amount of reactive oxygen species and the complexity of these enzymes and their functions suggest caution in the widespread use of vegan/vegetarian diets as human chemopreventive strategies. In fact, recent literature rather suggests that only diets rich in fruits and vegetables and poor in certain types of fat, together with moderate caloric intake, could be associated with reduced cancer risk.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

In der vorliegenden Arbeit werden vom ALEPH-Detektor am Speicherring LEP des CERN in Genf genommene Datenmengen aus den Jahren 1997 bis 1999 analysiert und sowohl Kopplungsparameter am Drei-Eichbosonen-Vertex derW-Boson-Paarproduktion, als auch die Anteile longitudinal beziehungsweise transversal polarisierter W-Bosonen, bei Schwerpunktsenergien von 183 GeV bis 202 GeV bestimmt. Betrachtet wird der rein leptonische Zerfallskanal, in dembeide W-Bosonen in ein Elektron-Neutrino- oder ein Myon-Neutrino-Paar zerfallen, der einen geringen Wirkungsquerschnitt aufweist, aber eine klareDetektorsignatur. Die aufgezeichneten Ereignisse werden selektiert und dabei eine Reinheit von durchschnittlich 72% erreicht. Der Hauptuntergrund besteht aus W-Boson-Paaren, bei denen zumindest ein W-Boson in ein Tauon-Neutrino-Paarzerfällt. Dieser Kanal zeigt ein sehr signalähnliches Verhalten. Die selektierten Ereignisse werden kinematisch rekonstruiert, um die Winkelverteilungen der Zerfallsprodukte der W-Bosonen zu extrahieren. Aus den Polarwinkelverteilungen der geladenen Zerfallsprodukte der W-Bosonen werden die Anteile longitudinal beziehungsweise transversal polarisierterW-Bosonen durch Anpassung der theoretischen Vorhersage an die selektierten Daten bestimmt. Dabei wird gefunden, daß f? = (71,6 ? 6,4_{stat.} ? 3,7_{syst.}) % der produzierten W-Bosonen transversal polarisiert sind, in Übereinstimmung mit der Vorhersage des Standardmodells (75,1%). Dieser Wert ist ein erster Hinweis auf die Kopplungsparameter am Drei-Eichbosonen-Vertex. Die CP-erhaltenden allgemeinen Kopplungsparameter $g_{rm Z}^1$, $kappa_gamma$ und $lambda_gamma$ werden bestimmt zu: $g_{rm Z}^1 = {{1,19^{+0,13}_{-0,16}}_{stat.}} {^{+0,09}_{-0,09}}_{syst.}$,$kappa_gamma = {{1,06^{+0,27}_{-0,09}}_{stat.}} {^{+0,08}_{-0,08}}_{syst.}$,$lambda_gamma = {{0,16^{+0,11}_{-0,13}}_{stat.}} {^{+0,08}_{-0,08}}_{syst.}$. Das Standardmodell sagt $g_{rm Z}^1 = 1$, $kappa_gamma = 1$ und $lambda_gamma = 0$ voraus. Mit diesen Kopplungsparametern lassen sich das magnetischeDipolmoment und das elektrische Quadrupolmoment der W-Bosonen bestimmen zu: $mu_{rm W} = frac{e}{2m_{rm W}} cdot (2,22^{+0,31}_{-0,19})$,$q_{rm W} = - frac{e}{m_{rm W}^2} cdot (0,90^{+0,32}_{-0,18})$. Die Messung der Kopplungsparameter stellt einen wichtigen Test des minimalen Standardmodells dar. In einem Jahr wird es möglich sein, diesen Test mit allen Daten aus der Phase II des Betriebs von LEP durchzuführen und die Genauigkeit durch Kombination mit anderen LEP-Experimenten zu erhöhen.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Background: Nilotinib is a potent and selective BCR-ABL inhibitor. The phase 3 ENESTnd trial demonstrated superior efficacy nilotinib vs imatinib, with higher and faster molecular responses. After 24 months, the rates of progression to accelerated-blastic phase (ABP) were 0.7% and 1.1% with nilotinib 300mg and 400mg BID, respectively, significantly lower compared to imatinib (4.2%). Nilotinib has been approved for the frontline treatment of Ph+ CML. With imatinib 400mg (IRIS trial), the rate of any event and of progression to ABP were higher during the first 3 years. Consequently, a confirmation of the durability of responses to nilotinib beyond 3 years is extremely important. Aims: To evaluate the response and the outcome of patients treated for 3 years with nilotinib 400mg BID as frontline therapy. Methods: A multicentre phase 2 trial was conducted by the GIMEMA CML WP (ClinicalTrials.gov.NCT00481052). Minimum 36-month follow-up data for all patients will be presented. Definitions: Major Molecular Response (MMR): BCR-ABL/ABL ratio <0,1%IS; Complete Molecular Response (CMR): undetectable transcript levels with ≥10,000 ABL transcripts; failures: according to the revised ELN recommendations; events: failures and treatment discontinuation for any reason. All the analysis has been made according to the intention-to-treat principle. Results: 73 patients enrolled: median age 51 years; 45% low, 41% intermediate and 14% high Sokal risk. The cumulative incidence of CCgR at 12 months was 100%. CCgR at each milestone: 78%, 96%, 96%, 95%, 92% at 3, 6, 12, 18 and 24 months, respectively. The overall estimated probability of MMR was 97%, while the rates of MMR at 3, 6, 12, 18 and 24 months were 52%, 66%, 85%, 81% and 82%, respectively. The overall estimated probability of CMR was 79%, while the rates of CMR at 12 and 24 months were 12% and 27%, respectively. No patient achieving a MMR progressed to AP. Only one patient progressed at 6 months to ABP and subsequently died (high Sokal risk, T315I mutation). Adverse events were mostly grade 1 or 2 and manageable with appropriate dose adaptations. During the first 12 months, the mean daily dose was 600-800mg in 74% of patients. The nilotinib last daily dose was as follows: 800mg in 46 (63%) patients, 600mg in 3 (4%) patients and 400mg in 18 (25%), 6 permanent discontinuations. Detail of discontinuation: 1 patient progressed to ABP; 3 patients had recurrent episodes of amylase and/or lipase increase (no pancreatitis); 1 patient had atrial fibrillation (unrelated to study drug) and 1 patient died after 32 months of mental deterioration and starvation (unrelated to study drug). Two patients are currently on imatinib second-line and 2 on dasatinib third-line. With a median follow-up of 39 months, the estimated probability of overall survival, progression-free survival and failure-free survival was 97%, the estimated probability of event-free survival was 91%. Conclusions: The rate of failures was very low during the first 3 years. Responses remain stable. The high rates of responses achieved during the first 12 months are being translated into optimal outcome for most of patients.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Because of its aberrant activation, the PI3K/AKT/mTOR signaling pathway represents a pharmacological target in blast cells from patients with acute myelogenous leukemia (AML). Using Reverse Phase Protein Microarrays (RPMA), we have analyzed 20 phosphorylated epitopes of the PI3K/Akt/mTor signal pathway of peripheral blood and bone marrow specimens of 84 patients with newly diagnosed AML. Fresh blast cells were grown for 2 h, 4 h or 20 h untreated or treated with a panel of phase I or phase II Akt allosteric inhibitors, either alone or in combination with the mTOR kinase inhibitor Torin1 or the broad RTK inhibitor Sunitinib. By unsupervised hierarchical clustering a strong phosphorylation/activity of most of the sampled members of the PI3K/Akt/mTOR pathway was observed in 70% of samples from AML patients. Remarkably, however, we observed that inhibition of Akt phosphorylation, as well as of its substrates, was transient, and recovered or even increased far above basal level after 20 h in 60% samples. We demonstrated that inhibition of Akt induces FOXO-dependent insulin receptor expression and IRS-1 activation, attenuating the effect of drug treatment by reactivation of PI3K/Akt. Consistent with this model we found that combined inhibition of Akt and RTKs is much more effective than either alone, revealing the adaptive capabilities of signaling networks in blast cells and highliting the limations of these drugs if used as monotherapy.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The present research thesis was focused on the development of new biomaterials and devices for application in regenerative medicine, particularly in the repair/regeneration of bone and osteochondral regions affected by degenerative diseases such as Osteoarthritis and Osteoporosis or serious traumas. More specifically, the work was focused on the synthesis and physico-chemical-morphological characterization of: i) a new superparamagnetic apatite phase; ii) new biomimetic superparamagnetic bone and osteochondral scaffolds; iii) new bioactive bone cements for regenerative vertebroplasty. The new bio-devices were designed to exhibit high biomimicry with hard human tissues and with functionality promoting faster tissue repair and improved texturing. In particular, recent trends in tissue regeneration indicate magnetism as a new tool to stimulate cells towards tissue formation and organization; in this perspective a new superparamagnetic apatite was synthesized by doping apatite lattice with di-and trivalent iron ions during synthesis. This finding was the pin to synthesize newly conceived superparamagnetic bone and osteochondral scaffolds by reproducing in laboratory the biological processes yielding the formation of new bone, i.e. the self-assembly/organization of collagen fibrils and heterogeneous nucleation of nanosized, ionically substituted apatite mimicking the mineral part of bone. The new scaffolds can be magnetically switched on/off and function as workstations guiding fast tissue regeneration by minimally invasive and more efficient approaches. Moreover, in the view of specific treatments for patients affected by osteoporosis or traumas involving vertebrae weakening or fracture, the present work was also dedicated to the development of new self-setting injectable pastes based on strontium-substituted calcium phosphates, able to harden in vivo and transform into strontium-substituted hydroxyapatite. The addition of strontium may provide an anti-osteoporotic effect, aiding to restore the physiologic bone turnover. The ceramic-based paste was also added with bio-polymers, able to be progressively resorbed thus creating additional porosity in the cement body that favour cell colonization and osseointegration.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

I vegetali appartenenti alla famiglia delle Brassicaceae, sono ricchi di molecole biologicamente attive note per le numerose proprietà salutari. L’effetto di un estratto di germogli di cavolo nero toscano (TBCSE) è stato investigato, in termini chemiopreventivi, sugli enzimi epatici del metabolismo degli xenobiotici e antiossidanti, in ratti trattati con TBCSE. I risultati hanno mostrato un complesso pattern di modulazione, con una prevalente inibizione, del sistema citocromo P450-dipendente, e induzioni significative degli enzimi di fase II (glutatione transferasi e glucuronosiltransferasi) e antiossidanti (catalasi, NAD(P)H:chinone reduttasi, glutatione reduttasi e perossidasi). Successivamente, l’effetto di TBCSE è stato studiato nei confronti delle alterazioni provocate da un’alimentazione iperlipidica nel ratto. Il trattamento si è dimostrato efficace nel contrastare gli effetti deleteri dei grassi presenti nella dieta, come l’iperlipidemia, l’aumento del peso corporeo e del fegato, l’indebolimento delle attività degli enzimi antiossidanti e del potenziale detossificante a livello epatico. Complessivamente, TBCSE emerge essere un promettente prodotto nutraceutico con potenziali effetti chemiopreventivi, e da impiegare come strategia alimentare per contrastare gli effetti correlati ad una dieta iperlipidica. Il consumo di dosi sovralimentari di molecole isolate dalle Brassicaceae, tramite per esempio integratori dietetici, come strategia alimentare preventiva, potrebbe tuttavia rappresentare un rischio per la salute. La potenziale tossicità del sulforafane, glucorafanina, indolo-3-carbinolo, e 3,3'-diindolimetano, è stata valutata in epatociti primari di ratto. La citotossicità e l’induzione di stress ossidativo, osservate a concentrazioni non lontane da quelle che potrebbero essere raggiunte in vivo, insieme ad una forte modulazione dell’espressione genica, riguardante principalmente il metabolismo degli xenobiotici, risposte ad alterazioni dello stato ossidoredutivo, eventi di riparazione del DNA e di proteine, induzione dell’apoptosi, e meccanismi (co)cancerogeni, sottolineano la potenzialità di queste molecole di determinare un rischio tossicologico, in seguito ad un’assunzione prolungata e ad alte dosi.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Ischemic preconditioning is a complex cardioprotective phenomenon that involves adaptive changes in cells and molecules. This adaptation occurs in a biphasic pattern: an early phase which develops after 1-2 h, and a late phase that develops after 12-24 h. While it is widely accepted that reactive oxygen species (ROS) are strongly involved in triggering ischemic preconditiong, it is not clear if they play a major role in the early or late phase of preconditioning and which are the mechanisms involved. Methylglyoxal, a metabolic compound formed mainly from the glycolytic intermediate glyceraldehyde-3-phosphate., is a precursor of advanced glycation end product (AGEs) .It is more reactive than glucose and shows a stronger ability to cross-link with protein amino groups to form AGEs. Methylglyoxal induced cytotoxicity may be at least partially responsible for cardiovascular and Alzheimer diseases. Methylglyoxal omeostasis is controlled by the glyoxalase system that consists of two enzyme, glyoxalase 1 (GLO1) and glyoxalase 2. In a recent study it was demonstrated that the transcriptional levels of GLO1 are controlled by NF-E2-related factor 2 (Nrf2). The isothiocyanate sulforaphane, derived from the hydrolysis of glucoraphanin abundantly present in broccoli, represents one of the most potent inducers of phase II enzymes through the Keap1–Nrf2 pathway. The aim of this thesis was evaluated molecular mechanisms in cardio- and neuroprotection and the possibility of modulation by nutraceutical phytocomponents This thesis show to one side that the protection induced by H2O2 is mediated by detoxifying and antioxidant phase II enzymes induction, regulated, not only by transcriptional factor Nrf2, but also by Nrf1; on the other side our data represent an innovative result because for the first time it was demonstrated the possibility of inducing GLO1 by SF supplementation.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Lo studio CAVE PTX ha lo scopo di valutare la reale prevalenza della paratiroidectomia nei pazienti dializzati in Italia, verificare l’aderenza ai targets ematochimici proposti dalle linee guida internazionali K/DOQI e ricercare la presenza di fratture vertebrali e calcificazioni vascolari. Al momento attuale riportiamo i dati preliminari sulla prevalenza e le caratteristiche cliniche generali dei pazienti finora arruolati. Il nostro studio ha ricevuto contributi da 149 centri dialisi italiani, su un totale di 670, pari al 22%. La popolazione dialitica dalla quale sono stati ottenuti i casi di paratiroidectomia è risultata pari a 12515 pazienti;l’87,7% dei pazienti effettuava l’emodialisi mentre il 12,3% la dialisi peritoneale. Cinquecentoventotto, pari al 4,22%, avevano effettuato un intervento di paratiroidectomia (4,5%emodializzati, 1,9% in dialisi peritoneale;p<0.001). Abbiamo considerato tre gruppi differenti di PTH: basso (<150 pg/ml), ottimale (150 -300 pg/ml) ed elevato (>300 pg/ml). I valori medi di PTH e calcemia sono risultati significativamente diversi (più alti) tra casi e controlli nei due gruppi con PTH basso (PTX = 40±39 vs controllo = 92±42 pg/ml; p<.0001) e PTH alto (PTX= 630 ± 417 vs controllo 577 ±331; p<.05). La percentuale di pazienti con PTH troppo basso è risultata più elevata nei pazienti chirurgici rispetto al resto della popolazione (64vs23%; p<0.0001), mentre la percentuale dei casi con PTH troppo alto è risultata significativamente più alta nel gruppo di controllo (38%vs19%; p<0.003). Il 61% dei casi assumeva vitamina D rispetto al 64 % dei controlli; l’88% vs 75% un chelante del fosforo ed il 13%vs 35% il calciomimentico. In conclusione, la paratiroidectomia ha una bassa prevalenza in Italia, i pazienti sono più spesso di sesso femminile, in emodialisi e con età relativamente giovane ma da più tempo in dialisi.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Durch den Straßenbau an der Bundesstraße B3a veranlasst, wurden im Zeitraum vom 13.08.2007 bis zum 07.12.2007 archäologische Untersuchungen im Bereich der Streckenkilometer 19 bis 22 durch die Firma Archbau Essen, unter Kontrolle des Landesamtes für Denkmalpflege Hessen und der Kreisarchäologie Wetteraukreis durchgeführt. Bei km 19 wurde dabei eine Siedlung mit angrenzendem Gräberfeld aus der Linienbandkeramik (im Folgenden als LBK bezeichnet) festgestellt. Daneben ergaben sich eine Bestattung und ein Erdwerk der Michelsberger Kultur, Grubenkomplexe und ein Bronzehort aus der Urnenfelderkultur sowie eine mittelalterliche Straße.Heute liegt die Fundstelle Friedberg B3a km 19 in der südlichen Wetterau 30 km nördlich von Frankfurt am Main in Hessen an der Wetter 140 m über NN und gehört zum Wetteraukreis. rnDie 21 ha messende Ausgrabungsfläche umfasste insgesamt 344 Befunde. Die Identifikation der bandkeramischen Strukturen erfolgte hierbei vorwiegend durch die vergesellschaftete Keramik. Von zentraler Bedeutung sind die fünf Hausgrundrisse A bis E im nördlichen Sektor der Fundstelle, wobei die Präsenz zahlreicher „Dreipfostenriegel“ sowie die Nordost-Südwest Ausrichtung der Strukturen als Belege für eine Zeitstellung innerhalb der LBK angesehen werden. Über die Korrespondenzanalyse der bei den Siedlungsstrukturen angetroffenen Keramik konnte darüber hinaus eine Abfolge von Hausgenerationen erstellt werden. Daneben existierten eine Reihe weiterer Befunde von LBK-zeitlichen Pfostenstellungen, bei denen es sich um Zäune oder Palisaden gehandelt haben könnte. Südwestlich dieser Hausgrundrisse wurde bei den Ausgrabungen eine Grabenstruktur geschnitten, für die eine Funktion als Einfassung der bandkeramischen Siedlungsstrukturen möglich ist. Südlich dieser Grabenstruktur konnten sechs Hockerbestattungen der LBK festgestellt werden. Die räumliche Anordnung im Bereich der westlichen Grabungsgrenze lässt den Schluss zu, dass es sich hierbei um ein Gräberfeld handelt, welches bisher nur zu einem geringen Teil ergraben wurde. Ein Zusammenhang zu den Hausgrundrissen A bis E kann erwogen werden. Der nördliche Sektor der Fundstelle umfasste außerdem zahlreiche Grubenbefunde der LBK sowie einige Grubenkomplexe, wobei letztere als Lehmentnahmegruben anzusprechen sind. Abschließend soll hier noch auf die Existenz zweier bandkeramischer Öfen, darunter ein Grubenofen, im Südosten von Friedberg B3a km 19 hingewiesen werden. rnDen mit Abstand größten Anteil am bandkeramischen Fundmaterial aus Friedberg B3 km 19 hatte die Keramik mit 3428 Elementen. An Steingeräten konnten nur 12 Silices sowie 4 Beile und 14 Mahlsteine über die Typologie und die vergesellschaftete Keramik in die LBK eingeordnet werden. Bei den Knochengeräten zeigte sich ein einzelner beschädigter Kamm. Der Fokus der Analysen des bandkeramischen Fundmaterials aus Friedberg B3a km 19 lag auf der Keramik und deren Auswertung innerhalb von Seriation und Korrespondenzanalyse. Um den Untersuchungen mehr Validität zu verleihen und eine optimale Einordnung zu erreichen, wurden die Keramik-Daten aus Friedberg B3a km 19 mit anderen Datensätzen aus Südhessen kombiniert. Dabei war nicht nur die räumliche Nähe der Fundstellen entscheidend, sondern auch die stilistisch-typologische Nähe der Inventare. In Friedberg B3a km 19 waren die Phasen nach Meier-Arendt von einem frühen III bis zum Ende der Phase V anwesend. Phase II kann nur als marginal angesprochen werden. Es ließ sich kein Übergang zum Mittelneolithikum fassen. Nach der Interpretation aller relativchronologischer Daten könnte es sich in Friedberg B3a km 19 um eine Hausentwicklung mit sieben Phasen à 25 Jahren über 175 bis zu 200 Jahren handeln, die eine kontinuierliche Belegung des Platzes von der mittleren bis zum Ende der jüngsten LBK beschreibt. Insgesamt pflegt sich die Fundstelle Friedberg B3a km 19 so in die bandkeramische Siedlungslandschaft der südlichen Wetterau ein.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Glutathione-S-transferase of the Pi class (GSTP1) is frequently overexpressed in a variety of solid tumors and has been identified as a potential therapeutic target for cancer therapy. GSTP1 is a phase II detoxification enzyme and conjugates the tripeptide glutathione to endogenous metabolites and xenobiotics, thereby limiting the efficacy of antitumor chemotherapeutic treatments. In addition, GSTP1 regulates cellular stress responses and apoptosis by sequestering and inactivating c-Jun N-terminal kinase (JNK). Thiazolides are a novel class of antibiotics for the treatment of intestinal pathogens with no apparent side effects on the host cells and tissue. Here we show that thiazolides induce a GSTP1-dependent and glutathione-enhanced cell death in colorectal tumor cell lines. Downregulation of GSTP1 reduced the apoptotic activity of thiazolides, whereas overexpression enhanced it. Thiazolide treatment caused strong Jun kinase activation and Jun kinase-dependent apoptosis. As a critical downstream target of Jun kinase we identified the pro-apoptotic Bcl-2 homolog Bim. Thiazolides induced Bim expression and activation in a JNK-dependent manner. Downregulation of Bim in turn significantly blocked thiazolide-induced apoptosis. Whereas low concentrations of thiazolides failed to induce apoptosis directly, they potently sensitized colon cancer cells to TNF-related apoptosis-inducing ligand- and chemotherapeutic drug-induced cell death. Although GSTP1 overexpression generally limits chemotherapy and thus antitumor treatment, our study identifies GSTP1 as Achilles' heel and thiazolides as novel interesting apoptosis sensitizer for the treatment of colorectal tumors.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

BACKGROUND: The International Breast Cancer Study Group conducted a phase III trial in Australian/New Zealand (ANZ) and Swiss/German/Austrian (SGA) centres on training doctors in clear and ethical information delivery about treatment options and strategies to encourage shared decision making. METHODS: Medical, surgical, gynaecological and radiation oncologists, and their patients for whom adjuvant breast cancer therapy was indicated, were eligible. Doctors were randomised to participate in a workshop with standardised teaching material and role playing. Patients were recruited in the experimental and control groups before and after the workshop. RESULTS: In ANZ centres, 21 eligible doctors recruited a total of 304 assessable patients. In SGA centres, 41 doctors recruited 390 patients. The training was well accepted. There was no overall effect on patient decisional conflict (primary endpoint) 2 weeks after the consultation. Overall, patients were satisfied with their treatment decision, their consultation and their doctors' consultation skills. Considerable variation was observed in patient outcomes between SGA and ANZ centres; the effect sizes of the intervention were marginal (<0.2). CONCLUSIONS: Shared decision making remains a challenge. A sustained training effect may require more intensive training tailored to the local setting. Cross-cultural differences need attention in conducting trials on communication interventions.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

We report the results of a prospective, randomized phase 3 trial evaluating autologous peripheral blood stem cell transplantation (ASCT) versus intensive consolidation chemotherapy in newly diagnosed AML patients in complete remission (CR1). Patients with AML (16-60 years) in CR1 after 2 cycles of intensive chemotherapy and not eligible for allogeneic SCT were randomized between intensive chemotherapy with etoposide and mitoxantrone or ASCT ater high-dose cyclophosphamide and busulfan. Of patients randomized (chemotherapy, n = 259; ASCT, n = 258), more than 90% received their assigned treatment. The 2 groups were comparable with regard to prognostic factors. The ASCT group showed a markedly reduced relapse rate (58% vs 70%, P = .02) and better relapse-free survival at 5 years (38% vs 29%, P = .065, hazard ratio = 0.82; 95% confidence interval, 0.66-1.1) with nonrelapse mortality of 4% versus 1% in the chemotherapy arm (P = .02). Overall survival was similar (44% vs 41% at 5 years, P = .86) because of more opportunities for salvage with second-line chemotherapy and stem cell transplantation in patients relapsing on the chemotherapy arm. This large study shows a relapse advantage for ASCT as postremission therapy but similar survival because more relapsing patients on the chemotherapy arm were salvaged with a late transplantation for relapse. This trial is registered at www.trialregister.nl as #NTR230 and #NTR291.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

CE-ESI multistage IT-MS (CE-MS(n), n < or = 4) and computer simulation of fragmentation are demonstrated to be effective tools to detect and identify phase I and phase II metabolites of hydromorphone (HMOR) in human urine. Using the same CE conditions as previously developed for the analysis of urinary oxycodone and its metabolites, HMOR and its phase I metabolites produced by N-demethylation, 6-keto-reduction and N-oxidation and phase II conjugates of HMOR and its metabolites formed with glucuronic acid, glucose, and sulfuric acid could be detected in urine samples of a patient that were collected during a pharmacotherapy episode with daily ingestion of 48 mg of HMOR chloride. The CE-MS(n) data obtained with the HMOR standard, synthesized hydromorphol and hydromorphone-N-oxide, and CYP3A4 in vitro produced norhydromorphone were employed to identify the metabolites. This approach led to the identification of previously unknown HMOR metabolites, including HMOR-3O-glucide and various N-oxides, structures for which no standard compounds or mass spectra library data were available. Furthermore, the separation of alpha- and beta-hydromorphol, the stereoisomers of 6-keto-reduced HMOR, was achieved by CE in the presence of the single isomer heptakis(2,3-diacetyl-6-sulfato)-beta-CD. The obtained data indicate that the urinary excretion of alpha-hydromorphol is larger than that of beta-hydromorphol.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Lorazepam (LOR) is a 3-hydroxy-1,4-benzodiazepine that is chiral and undergoes enantiomerization at room temperature. In humans, about 75% of the administered dose of LOR is excreted in the urine as its 30-glucuronide. CE-MS with negative ESI was used to confirm the presence of LOR-30-glucuronide in urines that stemmed from a healthy individual who ingested 1 or 2 mg LOR, whereas free LOR could be detected in extracts prepared from enzymatically hydrolyzed urines. As the 30-glucuronidation reaction occurs at the chiral center of the molecule, two diastereoisomers can theoretically be formed, molecules that can no longer interconvert. The stereoselective formation of LOR glucuronides in humans and in vitro was investigated. MEKC analysis of extracts of the nonhydrolyzed urines suggested the presence of the two different LOR glucuronides in the urine. The formation of the same two diastereoisomers was also observed in vitro employing incubations of LOR with human liver microsomes in the presence of uridine 5'-diphospho-glucuronic acid as coenzyme. The absence of other coenzymes excluded the formation of phase I or other phase II metabolites of LOR. Both results revealed a stereoselectivity, one diastereoisomer being formed in a higher amount than the other. After enzymatic hydrolysis using beta-glucuronidase, these peaks could not be detected any more. Instead, LOR was monitored. Analysis of the extracts prepared from enzymatically hydrolyzed urines by MEKC in the presence of 2-hydroxypropyl-beta-CD revealed the enantiomerization process of LOR (observation of two peaks of equal magnitude connected with a plateau zone). The data presented provide for the first time the evidence of the stereoselectivity of the LOR glucuronidation in humans.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Colonisation of the gastrointestinal tract by anaerobic bacteria, protozoa, trematodes, cestodes and/or nematodes and other infectious pathogens, including viruses, represents a major cause of morbidity and mortality in Africa, South America and southeast Asia, as well as other parts of the world. Nitazoxanide is a member of the thiazolide class of drugs with a documented broad spectrum of activity against parasites and anaerobic bacteria. Moreover, the drug has recently been reported to have a profound activity against hepatitis C virus infection. In addition, nitazoxanide exhibits anti-inflammatory properties, which have prompted clinical investigations for its use in Crohn's disease. Studies with nitazoxanide derivatives have determined that there must be significantly different mechanisms of action acting on intracellular versus extracellular pathogens. An impressive number of clinical studies have shown that the drug has an excellent bioavailability in the gastrointestinal tract, is fast acting and highly effective against gastrointestinal bacteria, protozoa and helminthes. A recent Phase II study has demonstrated viral response (hepatitis C) to monotherapy, with a low toxicity and an excellent safety profile over 24 weeks of treatment. Pre-clinical studies have indicated that there is a potential for application of this drug against other diseases, not primarily affecting the liver or the gastrointestinal tract.