Circuit quantum electrodynamics has proven to be a powerful tool to probe mesoscopic effects in hybrid systems and is used in several quantum computing (QC) proposals that require a transmon qubit ...able to operate in strong magnetic fields. To address this we integrate monolayer graphene Josephson junctions into microwave frequency superconducting circuits to create graphene based transmons. Using dispersive microwave spectroscopy we resolve graphene's characteristic band dispersion and observe coherent electronic interference effects confirming the ballistic nature of our graphene Josephson junctions. We show that the monoatomic thickness of graphene renders the device insensitive to an applied magnetic field, allowing us to perform energy level spectroscopy of the circuit in a parallel magnetic field of 1 T, an order of magnitude higher than previous studies. These results establish graphene based superconducting circuits as a promising platform for QC and the study of mesoscopic quantum effects that appear in strong magnetic fields.
Background Ectonucleotidases maintain vascular homeostasis by metabolizing extracellular nucleotides, modulating inflammation and thrombosis, and potentially, myocardial flow through adenosine ...generation. Evidence implicates dysfunction or deficiency of ectonucleotidases CD39 or CD73 in human disease; the utility of measuring levels of circulating ectonucleotidases as plasma biomarkers of coronary artery dysfunction or disease has not been previously reported. Methods and Results A total of 529 individuals undergoing clinically indicated positron emission tomography stress testing between 2015 and 2019 were enrolled in this single-center retrospective analysis. Baseline demographics, clinical data, nuclear stress test, and coronary artery calcium score variables were collected, as well as a blood sample. CD39 and CD73 levels were assessed as binary (detectable, undetectable) or continuous variables using ELISAs. Plasma CD39 was detectable in 24% of White and 8% of Black study participants (
=0.02). Of the clinical history variables examined, ectonucleotidase levels were most strongly associated with underlying liver disease and not other traditional coronary artery disease risk factors. Intriguingly, detection of circulating ectonucleotidase was inversely associated with stress myocardial blood flow (2.3±0.8 mL/min per g versus 2.7 mL/min per g±1.1 for detectable versus undetectable CD39 levels,
<0.001) and global myocardial flow reserve (Pearson correlation between myocardial flow reserve and log(CD73) -0.19,
<0.001). A subanalysis showed these differences held true independent of liver disease. Conclusions Vasodilatory adenosine is the expected product of local ectonucleotidase activity, yet these data support an inverse relationship between plasma ectonucleotidases, stress myocardial blood flow (CD39), and myocardial flow reserve (CD73). These findings support the conclusion that plasma levels of ectonucleotidases, which may be shed from the endothelial surface, contribute to reduced stress myocardial blood flow and myocardial flow reserve.
PAX8-PPARγ1 Fusion in Oncogene Human Thyroid Carcinoma Kroll, Todd G.; Sarraf, Pasha; Pecciarini, Lorenza ...
Science (American Association for the Advancement of Science),
08/2000, Letnik:
289, Številka:
5483
Journal Article
Recenzirano
Chromosomal translocations that encode fusion oncoproteins have been observed consistently in leukemias/lymphomas and sarcomas but not in carcinomas, the most common human cancers. Here, we report ...that t(2;3)(q13;p25), a translocation identified in a subset of human thyroid follicular carcinomas, results in fusion of the DNA binding domains of the thyroid transcription factor PAX8 to domains A to F of the peroxisome proliferator-activated receptor (PPAR) γ1. PAX8-PPARγ1 mRNA and protein were detected in 5 of 8 thyroid follicular carcinomas but not in 20 follicular adenomas, 10 papillary carcinomas, or 10 multinodular hyperplasias. PAX8-PPARγ1 inhibited thiazolidinedione-induced transactivation by PPARγ1 in a dominant negative manner. The experiments demonstrate an oncogenic role for PPARγ and suggest that PAX8-PPARγ1 may be useful in the diagnosis and treatment of thyroid carcinoma.
A series of 88 conventional follicular and Hürthle cell thyroid tumors were analyzed for RAS mutations and PAX8-PPARγ rearrangements using molecular methods and for galectin-3 and HBME-1 expression ...by immunohistochemistry. A novel LightCycler technology-based method was developed to detect point mutations in codons 12/13 and 61 of the H-RAS, K-RAS, and N-RAS genes. Forty-nine percent of conventional follicular carcinomas had RAS mutations, 36% had PAX8-PPARγ rearrangement, and only one (3%) had both. In follicular adenomas, 48% had RAS mutations, 4% had PAX8-PPARγ rearrangement, and 48% had neither. Follicular carcinomas with PAX8-PPARγ typically showed immunoreactivity for galectin-3 but not for HBME-1, tended to present at a younger patient age and be smaller size, and were almost always overtly invasive. In contrast, follicular carcinomas with RAS mutations most often displayed an HBME-1-positive/galectin-3-negative immunophenotype and were either minimally or overtly invasive. Hürthle cell tumors infrequently had PAX8-PPARγ rearrangement or RAS mutations. These results suggest that conventional follicular thyroid carcinomas develop through at least two distinct and virtually nonoverlapping molecular pathways initiated by either RAS point mutation or PAX8-PPARγ rearrangement.
Akt/PKB is a crucial regulator of diverse cellular processes and contributes to cancer progression. Activation of Akt is essentially dependent on phosphatidylinositol (PI) 3-kinase signaling. Here, ...we describe a novel mediator of Akt that is independent of PI 3-kinase. This mediator, PIKE-A, is a PIKE isoform and contains GTPase, pleckstrin homology, ArfGAP, and ankyrin repeats domains. PIKE-A directly binds to activated Akt but not PI 3-kinase in a guanine nucleotide-dependent way and stimulates the kinase activity of Akt. Overexpression of PIKE-A enhances Akt activity and promotes cancer cell invasion, whereas dominant-negative PIKE-A and PIKE-A knockdown markedly inhibit these processes. Our results demonstrate that PIKE-A is a physiologic regulator of Akt and an oncogenic effector of cell invasion.
PIKE-A (PIKE-activating Akt), an isoform of PIKE GTPase that enhances phosphatidylinositol 3-kinase (PI3-kinase) activity, specifically binds to active Akt but not PI3-kinase. PIKE-A stimulates Akt ...activity in a GTP-dependent manner and promotes invasiveness of cancer cell lines. Here, we show that PIKE-A is amplified in a variety of human cancers and that amplified PIKE-A directly stimulates Akt and inhibits apoptosis compared to cells with normal PIKE-A copy number. Overexpression of PIKE-A wild-type but not dominant-negative mutant stimulates Akt activity and prevents apoptosis. Moreover, knockdown of PIKE-A diminishes Akt activity and increases apoptosis. Our findings suggest that PIKE-A amplification contributes to cancer cell survival and progression by inhibiting apoptosis through up-regulating Akt.
PAX8-PPAR γ 1 Fusion in Oncogene Human Thyroid Carcinoma Kroll, Todd G.; Sarraf, Pasha; Pecciarini, Lorenza ...
Science (American Association for the Advancement of Science),
08/2000, Letnik:
289, Številka:
5483
Journal Article
Recenzirano
Chromosomal translocations that encode fusion oncoproteins have been observed consistently in leukemias/lymphomas and sarcomas but not in carcinomas, the most common human cancers. Here, we report ...that t(2;3)(q13;p25), a translocation identified in a subset of human thyroid follicular carcinomas, results in fusion of the DNA binding domains of the thyroid transcription factor PAX8 to domains A to F of the peroxisome proliferator–activated receptor (PPAR) γ1. PAX8-PPARγ1 mRNA and protein were detected in 5 of 8 thyroid follicular carcinomas but not in 20 follicular adenomas, 10 papillary carcinomas, or 10 multinodular hyperplasias. PAX8-PPARγ1 inhibited thiazolidinedione-induced transactivation by PPARγ1 in a dominant negative manner. The experiments demonstrate an oncogenic role for PPARγ and suggest that PAX8-PPARγ1 may be useful in the diagnosis and treatment of thyroid carcinoma.
Translocation t(15;19)(q13;p13.1) defines a lethal midline carcinoma arising adjacent to respiratory tract in young people. To characterize molecular alterations responsible for the distinctly ...aggressive biological behavior of this cancer, we mapped the chromosome 15 and 19 translocation breakpoints by fluorescence
in situ hybridization (FISH) and Southern blotting. To evaluate preliminarily the frequency, anatomical distribution, and histological features of t(15;19) cancer, we developed a FISH assay for paraffin sections. Our findings reveal a novel oncogenic mechanism in which the chromosome 19 translocation breakpoint interrupts the coding sequence of a bromodomain gene,
BRD4. These studies implicate
BRD4 as a potential partner in a t(15;19)-associated fusion oncogene. In addition, we localized the chromosome 15 breakpoint to a 9-kb region in each of two cases, thereby identifying several candidate oncogenes which might represent the
BRD4 fusion partner. FISH evaluation of 13 pediatric carcinomas revealed t(15;19) in one of four sinonasal carcinomas, whereas this translocation was not detected in thymic (
n = 3), mucoepidermoid (
n = 3), laryngeal (
n = 2), or nasopharyngeal (
n = 1) carcinomas. Our studies shed light on the oncogenic mechanism underlying t(15;19) and provide further evidence that this highly lethal cancer arises from respiratory mucosa.