980 resultados para 1,1 diphenyl 2 picrylhydrazyl


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The aim of this study was to determine the influence of climatic conditions on the hematological profile of Saanen and mixed-breed (1/2 Saanen x 1/2 Anglo-Nubian) goats, as well as to define reference values for these animals bred in Ceara, Brazil. Thirty goats were utilized and blood samples were collected monthly during the rainy (February to May) and dry (August to November) periods to obtain an erythrogram a leukogram. The averange were compared by the t-Student test and Mann Whitney test, with parametric and non-parametric distribution of the data, respectively, where p<0.05 was considered significant. A study was carried out of simple Pearson correlations of the hematological parameters with environmental and physiological variables. The number of red blood cells (RBCs) was higher in the Saanen goats and in the rainy period, while the hematocrit was higher in the dry period (p<0.05). The leukocytes and lymphocytes were higher in the 1/2S1/2 AN goats in the two periods (p<0.05). In the two genotypes, the leukocytes and lymphocytes were higher in the dry season and the segmented neutrophils higher in the rainy season (p<0.05). The other parameters did not differ (p>0.05). The RBCs and segmented neutrophils displayed a negative correlation with air temperature, but positive with relative humidity and rectal temperature (p<0.05). The hematocrit positively correlated with air temperature and respiratory rate (p<0.05). The leukocytes and lymphocytes showed a negative correlation with rectal temperature (p<0.05). It was therefore concluded that Saanen females are more affected by climatic variations and that the rainy season has a greater negative impact on hematological parameters. The values obtained could serve as a reference for these genotypes in Ceara.

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Conventional treatment of tuberculosis (TB) demands a long course therapy (6 months), known to originate multiple drug resistant strains (MDR-TB), which emphasizes the urgent need for new antituberculous drugs. The purpose of this study was to investigate a novel treatment for TB meant to improve patient compliance by reducing drug dosage frequency. Polymeric microparticles containing the synthetic analogue of neolignan, 1-phenyl-2-phenoxiethanone (LS-2), were obtained by a method of emulsification and solvent evaporation and chemically characterized. Only representative LS-2-loaded microparticles were considered for further studies involving experimental murine TB induced by Mycobacterium tuberculosis H37Rv ATCC 27294. The LS-2-loaded microparticles were spherical in shape, had a smooth wall and showed an encapsulation efficiency of 93% in addition to displaying sustained release. Chemotherapeutic potential of LS-2 entrapped in microparticles was comparable to control groups. These findings are encouraging and indicate that LS-2-loaded microparticles are a potential alternative to conventional chemotherapy of TB.

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Carnosine is present in high concentrations in skeletal muscle where it contributes to acid buffering and functions also as a natural protector against oxidative and carbonyl stress. Animal studies have shown an anti-diabetic effect of carnosine supplementation. High carnosinase activity, the carnosine degrading enzyme in serum, is a risk factor for diabetic complications in humans. The aim of the present study was to compare the muscle carnosine concentration in diabetic subjects to the level in non-diabetics. Type 1 and 2 diabetic patients and matched healthy controls (total n = 58) were included in the study. Muscle carnosine content was evaluated by proton magnetic resonance spectroscopy (3 Tesla) in soleus and gastrocnemius. Significantly lower carnosine content (-45%) in gastrocnemius muscle, but not in soleus, was shown in type 2 diabetic patients compared with controls. No differences were observed in type 1 diabetic patients. Type II diabetic patients display a reduced muscular carnosine content. A reduction in muscle carnosine concentration may be partially associated with defective mechanisms against oxidative, glycative and carbonyl stress in muscle.

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Four liquid crystals (LC) 3,7a-bis(4-alkyloxyphenyl)-7,7a-dihydro-6H-isoxazolo[2,3-d][1,2,4]oxadiazol-6-yl)acetic acid (7a-d) were synthesised and the mesomorphic behaviour reported. The LCs were characterised as 2: 1 bisadducts, which were obtained from a double [3+2] 1,3-dipolar cycloaddition. In the first step, the cycloaddition of 4-alkyloxyphenylnitrile oxide (4a-d) and vinylacetic acid (5) gave the initial unobserved 1:1 cycloadducts 2-[3-(4-alkyloxyphenyl)-4,5-dihydroisoxazol-5-yl]acetic acid (6a-d). In the second step, the addition of a second equivalent of 4 to 6 yielded the 2: 1 bisadducts 7a-d without any traces of 6. All compounds 7a-d were unstable during the transition from the mesophase to the isotropic state upon first heating as evidenced by the large peaks in the differential scanning calorimetry traces. Due to the chemical instability of the compounds upon heating, the transition temperature related to the smectic C to smectic A transitions was acquired by means of an image processing method. X-Ray diffraction experiments were also used to analyse the liquid-crystalline phases. A theoretical calculation was performed using density functional theory (DFT) methods at the PBE1PBE/6-311+G(2d,p) level (with solvent effect) in order to get information about the energetic profile of the 2: 1 cycloaddition. DFT studies revealed that the cycloaddition process is controlled by the HOMO(dipolarophile) - LUMO(1,3-dipole), and that the double [3+2] 1,3-dipolar cycloaddition reaction is quite possible.

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The Carr-Purcell pulse sequence, with low refocusing flip angle, produces echoes midway between refocusing pulses that decay to a minimum value dependent on T*(2). When the refocusing flip angle was pi/2 (CP90) and tau > T*(2), the signal after the minimum value, increased to reach a steady-state free precession regime (SSFP), composed of a free induction decay signal after each pulse and an echo, before the next pulse. When tau < T*(2), the signal increased from the minimum value to the steady-state regime with a time constant (T*) = 2T(1)T(2)/(T-1 + T-2). identical to the time constant observed in the SSFP sequence, known as the continuous wave free precession (CWFP). The steady-state amplitude obtained with M-cp90 = M0T2/(T-1+T-2) was identical to CWFP. Therefore, this sequence was named CP-CWFP because it is a Carr-Purcell sequence that produces results similar to the CWFP. However, CP-CWFP is a better sequence for measuring the longitudinal and transverse relaxation times in single scan, when the sample exhibits T-1 similar to T-2. Therefore, this sequence can be a useful method in time domain NMR and can be widely used in the agriculture, food and petrochemical industries because those samples tend to have similar relaxation times in low magnetic fields. (C) 2011 Elsevier Inc. All rights reserved.

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We present ab-initio calculations of seven digital magnetic heterostructures, GaN delta-doped with V, Cr, Mn, Fe, Co, Ni, and Cu, forming two-dimensional systems. Only GaN delta-doped with V or Cr present a ferromagnetic ground state with high Curie temperatures. For both, to better describe the electronic properties, we used the GGA-1/2 approach. The ground state of GaN/Cr resulted in a two dimensional half-metal, with 100% spin polarization. For GaN/V, we obtained an insulating state: integer magnetic moment of 2.0 mu(B), a minority spin gap of 3.0 eV close to the gap of GaN, but a majority spin gap of 0.34 eV. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4751285]

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Das menschliche Gen human giant larvae (hugl) ist ein Homolog des hochkonservierten Drosophila Gens lethal giant larvae (lgl), welches in Epithelzellen die Funktion eines neoplastischen Tumorsuppressors und Polaritätsregulators einnimmt. Ein Verlust oder eine verminderte Expression beider Homologe des Gens, hugl-1 und hugl-2, geht einher mit dem Auftreten und der Progression verschiedener epithelialer Tumorerkrankungen wie malignen Melanomen und Brust-, Kolon- oder Lungentumoren. Die exakte Funktion der Homologe Hugl-1 und Hugl-2 bezüglich der Regulation und Aufrechterhaltung der epithelialen Zellpolarität sowie ihre Rolle in der Genese humaner Tumore ist jedoch weitgehend unbekannt. Gänzlich unbekannt ist auch die Bedeutung von Hugl-1 und Hugl-2 als Polaritätsregulatoren für die Ausbildung und den Erhalt der T-Zellmorphologie und -funktion. Ziel der vorliegenden Arbeit war es daher, die Polaritäts- und Tumorsuppressorgene hugl-1 und hugl-2 in funktionellen Analysen mittels siRNA-vermitteltem Gen-Silencing in Epithelzellen und T-Lymphozyten zu charakterisieren. Darüber hinaus wurden die Funktionen und Eigenschaften von mgl-2, dem murinen Homologen von hugl-2, im Cre/loxP-vermittelten konditionalen Knockout Mausmodell in vivo analysiert.rnrnZur Charakterisierung der biologischen Effekte von Hugl-1 und Hugl-2 auf das Wachstumsverhalten, Migration und Invasion von Epithelzellen wurden in dieser Arbeit erfolgreich unterschiedliche shRNA-Expressionskonstrukte generiert sowie Hugl-supprimierte Zelllinien etabliert. In vitro Studien sowie in vivo Tumorigenizitätsanalysen lieferten übereinstimmend Hinweise darauf, dass verminderte Hugl-1- und Hugl-2-Expressionsspiegel eine signifikante Rolle in der Vermittlung invasiver und tumorigener Eigenschaften von Epithelzellen spielen. Dabei rief der Verlust beider Homologe deutlich stärkere Reaktionen hervor als die Suppression eines einzelnen Homologen. Zudem wiesen die Überexpression des Zellzyklusregulators Cyclin D1 sowie die Hyperproliferation von Hugl-1- und/oder Hugl-2-depletierten Epithelzellen auf eine wichtige Rolle der beiden Homologe in der Zellzyklusprogression und Zellproliferation hin. Ein geringer Expressionsstatus von Hugl-1 und -2 schien darüber hinaus mit einer verstärkten Resistenzbildung gegenüber Chemotherapeutika zu korrelieren. Im Rahmen dieser Arbeit konnte weiterhin gezeigt werden, dass die untersuchten T-Lymphozyten nur Hugl-1 exprimieren und dass letzteres notwendig für den F-Aktin-vermittelten Erhalt der T-Zellpolarität und -morphologie ist. Hugl-1-supprimierte, über voneinander unabhängige Signalwege (TCR- oder Chemokinrezeptor) stimulierte T-Lymphozyten wiesen eine bedeutende Störung der Lamellipodien- und Uropodausbildung auf und ließen eine Interaktion von Hugl-1 auf Ebene des F Aktins vermuten. Des Weiteren zeigte sich, dass der Polaritätsregulator Hugl-1 die CD3/TCR-induzierte Zelladhäsion positiv beeinflusst. Die Analyse der T-Zellmigration und -motilität offenbarte in Übereinstimmung dazu die Wichtigkeit von Hugl-1 für die Polarisierung und Migration der T-Zellen sowohl im Chemokingradienten als auch auf mDCs. rnrnFür die Aufklärung der funktionellen Rolle von mgl-2 in vivo wurde in dieser Arbeit eine Tamoxifen-induzierbare, Cre/loxP-vermittelte konditionale Mauslinie generiert und analysiert. Die mgl-2-deletierten Tiere wiesen weder signifikante phänotypische Unterschiede noch Abweichungen in der Organanatomie auf und ließen daher auf eine Kompensation durch das im Darmepithel koexprimierte und möglicherweise funktionell redundante mgl-1 Gen schließen.rn

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Neuronal precursor cell-expressed developmentally down-regulated 4 (Nedd4) proteins are ubiquitin ligases, which attach ubiquitin moieties to their target proteins, a post-translational modification that is most commonly associated with protein degradation. Nedd4 ubiquitin ligases have been shown to down-regulate both potassium and sodium channels. In this study, we investigated whether Nedd4 ubiquitin ligases also regulate Ca(v) calcium channels. We expressed three Nedd4 family members, Nedd4-1, Nedd4-2, and WWP2, together with Ca(v)1.2 channels in tsA-201 cells. We found that Nedd4-1 dramatically decreased Ca(v) whole-cell currents, whereas Nedd4-2 and WWP2 failed to regulate the current. Surface biotinylation assays revealed that Nedd4-1 decreased the number of channels inserted at the plasma membrane. Western blots also showed a concomitant decrease in the total expression of the channels. Surprisingly, however, neither the Ca(v) pore-forming α1 subunit nor the associated Ca(v)β and Ca(v)α(2)δ subunits were ubiquitylated by Nedd4-1. The proteasome inhibitor MG132 prevented the degradation of Ca(v) channels, whereas monodansylcadaverine and chloroquine partially antagonized the Nedd4-1-induced regulation of Ca(v) currents. Remarkably, the effect of Nedd4-1 was fully prevented by brefeldin A. These data suggest that Nedd4-1 promotes the sorting of newly synthesized Ca(v) channels for degradation by both the proteasome and the lysosome. Most importantly, Nedd4-1-induced regulation required the co-expression of Ca(v)β subunits, known to antagonize the retention of the channels in the endoplasmic reticulum. Altogether, our results suggest that Nedd4-1 interferes with the chaperon role of Ca(v)β at the endoplasmic reticulum/Golgi level to prevent the delivery of Ca(v) channels at the plasma membrane.

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Radiolabeled antagonists of specific peptide receptors identify a higher number of receptor binding sites than agonists and may thus be preferable for in vivo tumor targeting. In this study, two novel radioiodinated 1,4-benzodiazepines, (S)-1-(3-iodophenyl)-3-(1-methyl-2-oxo-5-phenyl-2,3-dihydro-1H-benzo[e][1,4]diazepin-3-yl)urea (9) and (R)-1-(3-iodophenyl)-3-(1-methyl-2-oxo-5-phenyl-2,3-dihydro-1H-benzo[e][1,4]diazepin-3-yl)urea (7), were developed. They were characterized in vitro as high affinity selective antagonists at cholecystokinin types 1 and 2 (CCK(1) and CCK(2)) receptors using receptor binding, calcium mobilization, and internalization studies. Their binding to human tumor tissues was assessed with in vitro receptor autoradiography and compared with an established peptidic CCK agonist radioligand. The (125)I-labeled CCK(1) receptor-selective compound 9 often revealed a substantially higher amount of CCK(1) receptor binding sites in tumors than the agonist (125)I-CCK. Conversely, the radioiodinated CCK(2) receptor-selective compound 7 showed generally weaker tumor binding than (125)I-CCK. In conclusion, compound 9 is an excellent radioiodinated nonpeptidic antagonist ligand for direct and selective labeling of CCK(1) receptors in vitro. Moreover, it represents a suitable candidate to test antagonist binding to CCK(1) receptor-expressing tumors in vivo.

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Bistriazoles, 1,3-bis(1,2,4-triazol-4-yl)propane (tr2pr) and 1,3-bis(1,2,4-triazol-4-yl)adamantane (tr2ad), were examined in combination with the rigid tetratopic 1,3,5,7-adamantanetetracarboxylic acid (H4-adtc) platform for the construction of neutral heteroleptic copper(II) metal−organic frameworks. Two coordination polymers, [{Cu4(OH)2(H2O)2}{Cu4(OH)2}(tr2pr)2(H-adtc)4]·2H2O (1) and [Cu4(OH)2(tr2ad)2(H-adtc)2(H2O)2]·3H2O (2), were synthesized and structurally characterized. In complexes 1 and 2, the N1,N2-1,2,4-triazolyl (tr) and μ3-OH− groups serve as complementary bridges between adjacent metal centers supporting the tetranuclear dihydroxo clusters. The structure of 1 represents a unique association of two different kinds of centrosymmetrical {Cu4(OH)2} units in a tight 3D framework, while in compound 2, another configuration type of acentric tetranuclear metal clusters is organized in a layered 3,6-hexagonal motif. In both cases, the {Cu4(OH)2} secondary building block and trideprotonated carboxylate H-adtc3− can be viewed as covalently bound six- and three-connected nodes that define the net topology. The tr ligands, showing μ3- or μ4-binding patterns, introduce additional integrating links between the neighboring {Cu4(OH)2} fragments. A variable-temperature magnetic susceptibility study of 2 demonstrates strong antiferromagnetic intracluster coupling (J1 = −109 cm−1 and J2 = −21 cm−1), which combines for the bulk phase with a weak antiferromagnetic intercluster interaction (zj = −2.5 cm−1).

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BACKGROUND Trastuzumab has established efficacy against breast cancer with overexpression or amplification of the HER2 oncogene. The standard of care is 1 year of adjuvant trastuzumab, but the optimum duration of treatment is unknown. We compared 2 years of treatment with trastuzumab with 1 year of treatment, and updated the comparison of 1 year of trastuzumab versus observation at a median follow-up of 8 years, for patients enrolled in the HERceptin Adjuvant (HERA) trial. METHODS The HERA trial is an international, multicentre, randomised, open-label, phase 3 trial comparing treatment with trastuzumab for 1 and 2 years with observation after standard neoadjuvant chemotherapy, adjuvant chemotherapy, or both in 5102 patients with HER2-positive early breast cancer. The primary endpoint was disease-free survival. The comparison of 2 years versus 1 year of trastuzumab treatment involved a landmark analysis of 3105 patients who were disease-free 12 months after randomisation to one of the trastuzumab groups, and was planned after observing at least 725 disease-free survival events. The updated intention-to-treat comparison of 1 year trastuzumab treatment versus observation alone in 3399 patients at a median follow-up of 8 years (range 0-10) is also reported. This study is registered with ClinicalTrials.gov, number NCT00045032. FINDINGS We recorded 367 events of disease-free survival in 1552 patients in the 1 year group and 367 events in 1553 patients in the 2 year group (hazard ratio [HR] 0·99, 95% CI 0·85-1·14, p=0·86). Grade 3-4 adverse events and decreases in left ventricular ejection fraction during treatment were reported more frequently in the 2 year treatment group than in the 1 year group (342 [20·4%] vs 275 [16·3%] grade 3-4 adverse events, and 120 [7·2%] vs 69 [4·1%] decreases in left ventricular ejection fraction, respectively). HRs for a comparison of 1 year of trastuzumab treatment versus observation were 0·76 (95% CI 0·67-0·86, p<0·0001) for disease-free survival and 0·76 (0·65-0·88, p=0·0005) for overall survival, despite crossover of 884 (52%) patients from the observation group to trastuzumab therapy. INTERPRETATION 2 years of adjuvant trastuzumab is not more effective than is 1 year of treatment for patients with HER2-positive early breast cancer. 1 year of treatment provides a significant disease-free and overall survival benefit compared with observation and remains the standard of care. FUNDING F Hoffmann-La Roche (Roche).

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There is increasing evidence that the complement system plays an important role in diabetes and the development of diabetic vascular complications. In particular, mannan-binding lectin (MBL) levels are elevated in diabetes patients, and diabetes patients with diabetic nephropathy have higher MBL levels than diabetes patients with normal renal function. The MBL-associated serine proteases (MASPs) MASP-1, MASP-2, and MASP-3, and MBL-associated protein MAp44 have not yet been studied in diabetes patients. We therefore measured plasma levels of MASP-1, MASP-2, MASP-3, and MAp44 in 30 children with type 1 diabetes mellitus (T1DM) and 17 matched control subjects, and in 45 adults with T1DM and 31 matched control subjects. MASP-1 and MASP-2 levels were significantly higher in children and adults with T1DM than in their respective control groups, whereas MASP-3 and MAp44 levels did not differ between patients and controls. MASP-1 and MASP-2 levels correlated with HbA1c, and MASP levels decreased when glycaemic control improved. Since MASP-1 and MASP-2 have been shown to directly interact with blood coagulation, elevated levels of these proteins may play a role in the enhanced thrombotic environment and consequent vascular complications in diabetes.

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This paper describes the syntheses and characterization of two new copper(II) diphosphonates: [NH3(CH2)2NH3]2[Cu2(hedp)2]·H2O (1) and [NH3CH(CH3)CH2NH3]2[Cu2(hedp)2] (2) (hedp = 1-hydroxyethylidenediphosphonate). Both compounds exhibit similar one-dimensional linear chain structures. The symmetrical {Cu2(hedp)2} dimers are connected by edge-shared {CuO5} square pyramids and form infinite chains. The Cu(II) ions are alternately bridged by O–P–O groups and O atoms. The Cu–O–Cu angles are 95.8(1) and 96.1(1)° for 1 and 2, respectively. Their magnetic properties show moderately strong antiferromagnetic interactions in both compounds.