Publications de Hikari Ananda Infinity Yoshihara

Hyperpolarized (1-13C)Alaninamide Is a Multifunctional In Vivo Sensor of Aminopeptidase N Activity, pH, and CO2

Rolf Gruetter, Daniel Ortiz Trujillo, Hikari Ananda Infinity Yoshihara, Alice Radaelli

Spin hyperpolarization enables real-time metabolic imaging of carbon-13-labeled substrates. While hyperpolarized L- (1-13C)alaninamide is a probe of the cell-surface tumor marker aminopeptidase-N (APN, CD13), its activity in vivo has not been described. Sc ...

AMER CHEMICAL SOC2022

[13C]bicarbonate labelled from hyperpolarized [1-13C]pyruvate is an in vivo marker of hepatic gluconeogenesis in fasted state

Rolf Gruetter, Arnaud Comment, Josefina Adriana Maria Bastiaansen, Hikari Ananda Infinity Yoshihara, Emine Can

Hyperpolarized [1-13C]pyruvate enables direct in vivo assessment of real-time liver enzymatic activities by 13C magnetic resonance. However, the technique usually requires the injection of a highly supraphysiological dose of pyruvate. We herein demonstrate ...

2022

Dysfunction of the circadian clock in the kidney tubule leads to enhanced kidney gluconeogenesis and exacerbated hyperglycemia in diabetes

Laure Menin, Daniel Ortiz Trujillo, Hikari Ananda Infinity Yoshihara

The circadian clock is a ubiquitous molecular time-keeping mechanism which synchronizes cellular, tissue, and systemic biological functions with 24-hour environmental cycles. Local circadian clocks drive cell type- and tissuespecific rhythms and their dysr ...

2022

Performance and reproducibility of C-13 and N-15 hyperpolarization using a cryogen-free DNP polarizer

Hikari Ananda Infinity Yoshihara, Arianna Ferrari

The setup, operational procedures and performance of a cryogen-free device for producing hyperpolarized contrast agents using dissolution dynamic nuclear polarization (dDNP) in a preclinical imaging center is described. The polarization was optimized using ...

Nature Portfolio2022

Radical-free hyperpolarized MRI using endogenously occurring pyruvate analogues and UV-induced nonpersistent radicals

Rolf Gruetter, Andrea Capozzi, Josefina Adriana Maria Bastiaansen, Hikari Ananda Infinity Yoshihara, Alice Radaelli, Claudia Christina Zanella, Lionel Pierre Arn

It was recently demonstrated that nonpersistent radicals can be generated in frozen solutions of metabolites such as pyruvate by irradiation with UV light, enabling radical-free dissolution dynamic nuclear polarization. Although pyruvate is endogenous, the ...

WILEY2021

Assessment of Aspartate and Bicarbonate Produced From Hyperpolarized [1-13C]Pyruvate as Markers of Renal Gluconeogenesis

Arnaud Comment, Hikari Ananda Infinity Yoshihara

As both a consumer and producer of glucose, the kidney plays a significant role in glucose homeostasis. Measuring renal gluconeogenesis requires invasive techniques, and less invasive methods would allow renal gluconeogenesis to be measured more routinely. ...

2021

HP agents and biochemical interactions

Hikari Ananda Infinity Yoshihara

The intense but transient increase in nuclear magnetic resonance signal provided by dynamic nuclear polarization (DNP) has enabled a range of new applications, including rapid, minimally-invasive metabolic imaging at the second timescale. This chapter prov ...

Academic Press2021

C-13 Dynamic Nuclear Polarization using SA-BDPA at 6.7 T and 1.1 K: Coexistence of Pure Thermal Mixing and Well-Resolved Solid Effect

Rolf Gruetter, Andrea Capozzi, Hikari Ananda Infinity Yoshihara, Alice Radaelli

SA-BDPA is a water-soluble, narrow-line width radical previously used for dynamic nuclear polarization (DNP) signal enhancement in solid-state magic angle spinning NMR spectroscopy. Here, we report the first study using SA-BDPA under dissolution DNP condit ...

AMER CHEMICAL SOC2020

Renal tubular arginase-2 participates in the formation of the corticomedullary urea gradient and attenuates kidney damage in ischemia-reperfusion injury in mice

Dmitri Firsov, Hikari Ananda Infinity Yoshihara, Jean-Luc Barras, Nicolas Dattner

Aim Arginase 2 (ARG2) is a mitochondrial enzyme that catalyses hydrolysis ofl-arginine into urea andl-ornithine. In the kidney, ARG2 is localized to the S3 segment of the proximal tubule. It has been shown that expression and activity of this enzyme are up ...

WILEY2020

Noninvasive rapid detection of metabolic adaptation in activated human T lymphocytes by hyperpolarized 13C magnetic resonance

Mor-Miri Mishkovsky, Arnaud Comment, Hikari Ananda Infinity Yoshihara, Nicolas Kunz, Emine Can

The metabolic shift induced in human CD4+ T lymphocytes by stimulation is characterized by an upregulation of glycolysis, leading to an augmentation in lactate production. This adaptation has already been highlighted with various techniques and reported in ...

Nature Research2020