Publications by authors named "Vibat C"

Introduction: A dynamic molecular biomarker that can identify early efficacy of immune checkpoint inhibitor (ICI) therapy remains an unmet clinical need. Here we evaluate if a novel circulating tumor DNA (ctDNA) assay, xM, used for treatment response monitoring (TRM), that quantifies changes in ctDNA tumor fraction (TF), can predict outcome benefits in patients treated with ICI alone or in combination with chemotherapy in a real-world (RW) cohort.

Methods: This retrospective study consisted of patients with advanced cancer from the Tempus de-identified clinical genomic database who received longitudinal liquid-based next-generation sequencing.

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Li Fraumeni syndrome (LFS) is a hereditary cancer predisposition syndrome caused by germline mutations in TP53. TP53 is the most common mutated gene in human cancer, occurring in 30-50% of glioblastomas (GBM). Here, we highlight a precision medicine platform to identify potential targets for a GBM patient with LFS.

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Background: Clinical outcomes in high-grade glioma (HGG) have remained relatively unchanged over the last 3 decades with only modest increases in overall survival. Despite the validation of biomarkers to classify treatment response, most newly diagnosed (ND) patients receive the same treatment regimen. This study aimed to determine whether a prospective functional assay that provides a direct, live tumor cell-based drug response prediction specific for each patient could accurately predict clinical drug response prior to treatment.

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Background: Personalized medicine requires accurate molecular profiling for targeted therapy decisions. Insufficient tissue yield or tumor heterogeneity frequently limits the correct tissue biomarker determination. As a noninvasive complement to traditional tissue biopsies, liquid biopsies detect and track cancer driver mutations from biofluids (e.

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Unlabelled: The aim of the study was to evaluate the performance of the HPV-HR test to detect high-risk human papillomavirus (HPV) in urine samples in comparison with a commercial molecular HPV test.

Materials And Methods: This is a prospective study, in which 350 patients diagnosed previously with cervical intraepithelial neoplasia (CIN) grade 2 or higher were enrolled. Urine and cervical specimens were collected.

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Human papillomavirus (HPV) testing from clinician-collected cervical and self-collected cervico-vaginal samples is more sensitive for detecting CIN2/CIN3 than cytology-based screening, stimulating interest in HPV testing from urine. The objective was to determine the performance of the Trovagene HPV test for the detection of CIN2 from urine and PreservCyt cervical samples. Women referred for colposcopy at St Mary's Hospital (London, United Kingdom), following abnormal cytology, were recruited to this diagnostic accuracy study by convenience sampling (September 2011 to April 2013).

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Tumor-derived cell-free DNA (cfDNA) from urine of patients with cancer offers noninvasive biological material for detection of cancer-related molecular abnormalities such as mutations in Exon 2 of A quantitative, mutation-enrichment next-generation sequencing test for detecting mutations in urine cfDNA was developed, and results were compared with clinical testing of archival tumor tissue and plasma cfDNA from patients with advanced cancer. With 90 to 110 mL of urine, the cfDNA test had an analytical sensitivity of 0.002% to 0.

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Introduction: In approximately 60% of patients with NSCLC who are receiving EGFR tyrosine kinase inhibitors, resistance develops through the acquisition of EGFR T790M mutation. We aimed to demonstrate that a highly sensitive and quantitative next-generation sequencing analysis of EGFR mutations from urine and plasma specimens is feasible.

Methods: Short footprint mutation enrichment next-generation sequencing assays were used to interrogate EGFR activating mutations and the T790M resistance mutation in urine or plasma specimens from patients enrolled in TIGER-X (NCT01526928), a phase 1/2 clinical study of rociletinib in previously treated patients with EGFR mutant-positive advanced NSCLC.

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Background: Urine testing for high-risk human papillomavirus (HR-HPV) detection could provide a non-invasive, simple method for cervical cancer screening.

Objectives: We examined whether HR-HPV detection is affected by urine collection time, portion of urine stream, or urine fraction tested, and assessed the performance of HR-HPV testing in urine for detection of cervical intraepithelial neoplasia grade II or worse (CIN2+).

Study Design: A total of 37 female colposcopy clinic attendees, ≥ 30 years, provided three urine samples: "first void" urine collected at home, and "initial stream" and "mid-stream" urine samples collected at the clinic later in the day.

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Nanobodies (Nbs) or single-domain antibodies are among the smallest and most stable binder scaffolds known. In vitro display is a powerful antibody discovery technique used worldwide. We describe the first adaptation of in vitro mRNA/cDNA display for the rapid, automatable discovery of Nbs against desired targets, and use it to discover the first ever reported nanobody against the human full-length glucose transporter, GLUT-1.

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Unlabelled: Patients with Langerhans cell histiocytosis (LCH) and Erdheim-Chester disease (ECD) have a high frequency of BRAF(V600E) mutations and respond to RAF inhibitors. However, detection of mutations in tissue biopsies is particularly challenging in histiocytoses due to low tumor content and stromal contamination. We applied a droplet-digital PCR assay for quantitative detection of the BRAF(V600E) mutation in plasma and urine cell-free (cf) DNA and performed a prospective, blinded study in 30 patients with ECD/LCH.

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Erdheim-Chester disease (ECD) is a rare histiocytosis with a high prevalence of BRAF V600E mutation (>50% of patients). Patients with BRAF-mutant ECD can respond to BRAF inhibitors. Unfortunately, the lack of adequate archival tissue often precludes BRAF testing.

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Ataxia telangiectasia (A-T) is an autosomal recessive disease caused by loss of function of the serine/threonine protein kinase ATM (ataxia telangiectasia mutated). A-T patients have a 250-700-fold increased risk of developing lymphomas and leukemias which are typically highly invasive and proliferative. In addition, a subset of adult acute lymphoblastic leukemias and aggressive B-cell chronic lymphocytic leukemias that occur in the general population show loss of heterozygosity for ATM.

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A kinetic reverse transcription-polymerase chain reaction (RT-PCR)-based assay is described that can discriminate and quantitate differentially spliced mRNAs. This assay should be generally applicable for high-throughput quantitation of differentially spliced transcripts. The utility of this method was assessed for spliced transcripts encoded by the human Na+-K+-2Cl- cotransporter gene hNKCC1.

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The trabecular meshwork (TM) of the eye plays a central role in modulating intraocular pressure by regulating aqueous humor outflow, although the mechanisms are largely unknown. We and others have shown previously that aqueous humor outflow facility is modulated by conditions that alter TM cell volume. We have also shown that the Na-K-Cl cotransport system is a primary regulator of TM cell volume and that its activity appears to be coordinated with net efflux pathways to maintain steady-state volume.

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Complex II (succinate:ubiquinone oxidoreductase) from Escherichia coli contains four different subunits. Two of the subunits (SDHC and SDHD) are hydrophobic and anchor the two more hydrophilic (flavin and iron-sulfur) subunits (SDHA and SDHB) to the cytoplasmic membrane. Previous studies have shown that the complex of SDHC/SDHD is required to maintain the heme B component of the enzyme and that the heme B is ligated to the protein by two histidine ligands.

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The Na-K-Cl cotransporter is an important regulator of endothelial cell volume and may also contribute to flux of Na and Cl across the endothelium of the blood-brain barrier. To date, two Na-K-Cl cotransport isoforms have been identified, the cotransporter in secretory epithelia, NKCC1, and that in absorptive renal epithelia, NKCC2. Our previous studies showed that a monoclonal antibody to the cotransporter of human colonic T84 epithelial cells, an NKCC1 isoform, recognizes a 170-kDa glycoprotein from endothelial cells.

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Our previous amino acid substitutions at the postulated lipid-exposed transmembrane segment M4 of the Torpedo californica acetylcholine receptor (AChR) focused on the alpha C418 position. A tryptophan substitution on the alpha C418 produced a 3-fold increase in normalized macroscopic response to acetylcholine in voltage-clamped Xenopus laevis oocytes (Lee et al., 1994).

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Complex II (succinate-ubiquinone oxidoreductase) from Escherichia coli is composed of four nonidentical subunits encoded by the sdhCDAB operon. Gene products of sdhC and sdhD are small hydrophobic subunits that anchor the hydrophilic catalytic subunits (flavoprotein and iron-sulfur protein) to the cytoplasmic membrane and are believed to be the components of cytochrome b556 in E. coli complex II.

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1. Chronic administration of nicotine up-regulates mammalian neuronal nicotinic acetylcholine receptors (nAChRs). A key hypothesis that explains up-regulation assumes that nicotine induces desensitization of receptor function.

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Electron paramagnetic resonance (EPR) and near-infrared magnetic circular dichroism (MCD) have been used to identify the ligands to the cytochrome b556 component of succinate: ubiquinone oxidoreductase (succinate dehydrogenase) from Escherichia coli. The 'highly axial low spin' (HALS) EPR spectrum suggests bis(histidine) ligation of the heme with the histidines in a staggered configuration. The near-infrared MCD spectrum exhibits a low energy maximum at 1600 nm which is also clearly indicative of bis(histidine) ligation of the heme iron.

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A number of gene replacements at different loci were constructed using covalently closed circular (ccc) plasmid DNA in the recB21 recC22 sbcB15 sbcC201 mutant of Escherichia coli (JC7623). Selected constructs representing deletions and insertion mutations formed from double-crossover events involving the ccc plasmid molecules and the genome were confirmed by Southern blots, and the frequency of double-crossover events was evaluated. It is reported that such mutants may be constructed without linearizing plasmid DNA, as described previously.

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Complex II (succinate:ubiquinone oxidoreductase) is an important component of both the tricarboxylic acid cycle and of the aerobic respiratory chains of eukaryotic and prokaryotic organisms. The enzyme has been purified from numerous sources and appears to be highly conserved from considerations of both the amino acid sequences of the catalytic subunits and from the prosthetic groups associated with the enzyme. The sdh operon has been cloned and sequenced from Escherichia coli, but the enzyme from this source has, so far, resisted attempts at biochemical purification.

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