128 research outputs found
How adenomyosis changes throughout pregnancy: A retrospective cohort study
Objective To study how adenomyosis changes during pregnancy and to possibly correlate these changes to maternal and fetal outcomes. Methods Retrospective exploratory cohort study including 254 women with a pre-conceptional/first-trimester scan to document adenomyosis and known obstetric outcome. If visible, adenomyosis signs were documented in each trimester and postpartum. Mann-Whitney U tests or chi(2) tests were used for continuous and categorical variables, respectively. Results A globular uterus was reported in 79% (n = 52) of women with adenomyosis in the first trimester, in 38% (n = 20) and 2% (n = 1) of women in the second and third trimesters, respectively, and postpartum in 77% (n = 34) of women. Asymmetrical thickening (n = 20, 30%) and cysts (n = 15, 23%) were only visible in 1st trimester. Adenomyosis was associated with miscarriage (odds ratio [OR] 5.9, 95% confidence interval [CI] 2.4-14.9, P < 0.001) also in normal conception only (OR 5.1, 95% CI 1.8-14.2, P = 0.002) or adjusting for maternal age (adjusted OR 5.9, 95% CI 2.3-15.2, P < 0.001). Gestational age at delivery was lower in adenomyosis (P = 0.004); the cesarean section rate was higher than in controls (OR 2.5, 95% CI 1.3-4.8, P = 0.007) also adjusting for age (adjusted OR 2.07, 95% CI 1.06-4.08, P = 0.035). Conclusions Signs of adenomyosis were visible but progressively disappeared in pregnancy; adenomyosis was associated with an increased risk of early miscarriage. Prospective studies are needed to confirm our results
Performance analysis of the European X-ray Free Electron Laser 3.9 GHz superconducting cavities
The limits of performance of the European XFEL 3.9 GHz superconducting cavities were investigated. Most cavities exhibited high field Q slope, reaching the breakdown field at approximately . We hypothesize that this limit is a feature of high frequency cavities and can be explained by a thermal model incorporating field dependent surface resistance. The results obtained from simulations were in good agreement with experimental data obtained at 2 K
Diagnostic SARS-CoV-2 Cycle Threshold Value Predicts Disease Severity, Survival, and Six-Month Sequelae in COVID-19 Symptomatic Patients
To date, there is no severe acute respiratory syndrome coronavirus 2-(SARS-CoV-2)-specific prognostic biomarker available. We assessed whether SARS-CoV-2 cycle threshold (Ct) value at diagnosis could predict novel CoronaVirus Disease 2019 (COVID-19) severity, clinical manifestations, and six-month sequelae. Hospitalized and outpatient cases were randomly sampled from the diagnoses of March 2020 and data collected at 6 months by interview and from the regional database for COVID-19 emergency. Patients were stratified according to their RNA-dependent-RNA-polymerase Ct in the nasopharyngeal swab at diagnosis as follows: Group A †20.0, 20.0 < group B †28.0, and Group C > 28.0. Disease severity was classified according to a composite scale evaluating hospital admission, worst oxygen support required, and survival. Two hundred patients were included, 27.5% in Groups A and B both, 45.0% in Group C; 90% of patients were symptomatic and 63.7% were hospitalized. The median time from COVID-19 onset to swab collection was five days. Lethality, disease severity, type, and number of signs and symptoms, as well as six-month sequelae distributed inversely among the groups with respect to SARS-CoV-2 Ct. After controlling for confounding, SARS-CoV-2 Ct at diagnosis was still associated with COVID-19-related death (p = 0.023), disease severity (p = 0.023), number of signs and symptoms (p < 0.01), and presence of six-month sequelae (p < 0.01). Early quantification of SARS-CoV-2 may be a useful predictive marker to inform differential strategies of clinical management and resource allocation
Stir bar-sorptive extraction, solid phase extraction and liquid-liquid extraction for levetiracetam determination in human plasma: comparing recovery rates
Levetiracetam (LEV), an antiepileptic drug (AED) with favorable pharmacokinetic profile, is increasingly being used in clinical practice, although information on its metabolism and disposition are still being generated. Therefore a simple, robust and fast liquid-liquid extraction (LLE) followed by high-performance liquid chromatography method is described that could be used for both pharmacokinetic and therapeutic drug monitoring (TDM) purposes. Moreover, recovery rates of LEV in plasma were compared among LLE, stir bar-sorptive extraction (SBSE), and solid-phase extraction (SPE). Solvent extraction with dichloromethane yielded a plasma residue free from usual interferences such as commonly co-prescribed AEDs, and recoveries around 90% (LLE), 60% (SPE) and 10% (SBSE). Separation was obtained using reverse phase Select B column with ultraviolet detection (235 nm). Mobile phase consisted of methanol:sodium acetate buffer 0.125 M pH 4.4 (20:80, v/v). The method was linear over a range of 2.8-220.0 ”g mL-1. The intra- and inter-assay precision and accuracy were studied at three concentrations; relative standard deviation was less than 10%. The limit of quantification was 2.8 ”g mL-1. This robust method was successfully applied to analyze plasma samples from patients with epilepsy and therefore might be used for pharmacokinetic and TDM purposes.</p
Structural basis for the magnesium-dependent activation of transketolase from Chlamydomonas reinhardtii
Background In photosynthetic organisms, transketolase (TK) is involved in the Calvin-Benson cycle and participates to the regeneration of ribulose-5-phosphate. Previous studies demonstrated that TK catalysis is strictly dependent on thiamine pyrophosphate (TPP) and divalent ions such as Mg2 +. Methods TK from the unicellular green alga Chlamydomonas reinhardtii (CrTK) was recombinantly produced and purified to homogeneity. Biochemical properties of the CrTK enzyme were delineated by activity assays and its structural features determined by CD analysis and X-ray crystallography. Results CrTK is homodimeric and its catalysis depends on the reconstitution of the holo-enzyme in the presence of both TPP and Mg2 +. Activity measurements and CD analysis revealed that the formation of fully active holo-CrTK is Mg2 +-dependent and proceeds with a slow kinetics. The 3DĂąstructure of CrTK without cofactors (CrTKapo) shows that two portions of the active site are flexible and disordered while they adopt an ordered conformation in the holo-form. Oxidative treatments revealed that Mg2 +participates in the redox control of CrTK by changing its propensity to be inactivated by oxidation. Indeed, the activity of holo-form is unaffected by oxidation whereas CrTK in the apo-form or reconstituted with the sole TPP show a strong sensitivity to oxidative inactivation. Conclusion These evidences indicate that Mg2 +is fundamental to allow gradual conformational arrangements suited for optimal catalysis. Moreover, Mg2 +is involved in the control of redox sensitivity of CrTK. General significance The importance of Mg2 +in the functionality and redox sensitivity of CrTK is correlated to light-dependent fluctuations of Mg2 +in chloroplasts
A stable explant culture of HER2/neu invasive carcinoma supported by alpha-Smooth Muscle Actin expressing stromal cells to evaluate therapeutic agents
<p>Abstract</p> <p>Background</p> <p>To gain a better understanding of the effects of therapeutic agents on the tumor microenvironment in invasive cancers, we developed a co-culture model from an invasive lobular carcinoma. Tumor cells expressing HER2/neu organize in nests surrounded by alpha-Smooth Muscle Actin (α-SMA) expressing tumor stroma to resemble the morphology of an invading tumor. This co-culture, Mammary Adenocarcinoma Model (MAM-1) maintains a 1:1 ratio of HER2/neu positive tumor cells to α-SMA-reactive stromal cells and renews this configuration for over 20 passages in vitro.</p> <p>Methods</p> <p>We characterized the cellular elements of the MAM-1 model by microarray analysis, and immunocytochemistry. We developed flow cytometric assays to evaluate the relative responses of the tumor and stroma to the tyrosine kinase inhibitor, Iressa.</p> <p>Results</p> <p>The MAM-1 gene expression profile contains clusters that represent the ErbB-2 breast cancer signature and stroma-specific clusters associated with invasive breast cancers. The stability of this model and the ability to antigenically label the tumor and stromal fractions allowed us to determine the specificity of Iressa, a receptor tyrosine kinase inhibitor, for targeting the tumor cell population. Treatment resulted in a selective dose-dependent reduction in phospho-pMEK1/2 and pp44/42MAPK in tumor cells. Within 24 h the tumor cell fraction was reduced 1.9-fold while the stromal cell fraction increased >3-fold, consistent with specific reductions in phospho-pp44/42 MAPK, MEK1/2 and PCNA in tumor cells and reciprocal increases in the stromal cells. Erosion of the tumor cell nests and augmented growth of the stromal cells resembled a fibrotic response.</p> <p>Conclusion</p> <p>This model demonstrates the specificity of Iressa for HER2/neu expressing tumor cells versus the tumor associated myofibroblasts and is appropriate for delineating effects of therapy on signal transduction in the breast tumor microenvironment and improving strategies that can dually or differentially target the tumor and stromal elements in the microenvironment.</p
Influence of HER2 expression on prognosis in metastatic triple-negative breast cancer-results from an international, multicenter analysis coordinated by the AGMT Study Group
Development and Pharmacological Characterization of Selective Blockers of 2-Arachidonoyl Glycerol Degradation with Efficacy in Rodent Models of Multiple Sclerosis and Pain
Stir bar-sorptive extraction, solid phase extraction and liquid-liquid extraction for levetiracetam determination in human plasma: comparing recovery rates
Levetiracetam (LEV), an antiepileptic drug (AED) with favorable pharmacokinetic profile, is increasingly being used in clinical practice, although information on its metabolism and disposition are still being generated. Therefore a simple, robust and fast liquid-liquid extraction (LLE) followed by high-performance liquid chromatography method is described that could be used for both pharmacokinetic and therapeutic drug monitoring (TDM) purposes. Moreover, recovery rates of LEV in plasma were compared among LLE, stir bar-sorptive extraction (SBSE), and solid-phase extraction (SPE). Solvent extraction with dichloromethane yielded a plasma residue free from usual interferences such as commonly co-prescribed AEDs, and recoveries around 90% (LLE), 60% (SPE) and 10% (SBSE). Separation was obtained using reverse phase Select B column with ultraviolet detection (235 nm). Mobile phase consisted of methanol:sodium acetate buffer 0.125 M pH 4.4 (20:80, v/v). The method was linear over a range of 2.8-220.0 ”g mL-1. The intra- and inter-assay precision and accuracy were studied at three concentrations; relative standard deviation was less than 10%. The limit of quantification was 2.8 ”g mL-1. This robust method was successfully applied to analyze plasma samples from patients with epilepsy and therefore might be used for pharmacokinetic and TDM purposes.</p
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