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Aldosterone is a kind of steroid hormone produced by the zona glomerulosa (ZG) cells of the adrenal cortex which plays a crucial regulatory role in fluid-electrolyte balance and blood pressure stability. Aldosterone biosynthesis is a calcium-dependent process, and ion channels play a key role in this process. Primary aldosteronism is closely related to mutations in ion channels. Recent studies have highlighted an intriguing relationship between the unique rosette structure of ZG cells and their electrical excitability. Elucidating the connection between rosettes and ZG cell electrical excitability as well as aldosterone secretion leads to a deeper understanding of the mechanisms regulating aldosterone secretion and may provide new insights into the pathogenesis of primary aldosteronism.

Hydrogenation of tungsten trioxide (WO3) can effectively modulate its material property and induce the insulator–metal transition. Due to the insertion of H atoms, a transparent WO3 film will normally change to deep-blue color because of its pronounced electrochromism. More importantly, the electronic structure will also convert from an insulator to a metallic state, showing greatly improved conductivity with an enhancement of up to six orders of magnitude. Combined with the traditional lithography route, selective hydrogenation of WO3 in microscale size is achieved based on the electron–proton synergistic effect in an acid solution. This metal-like conductive H-doped WO3 can be used as an erasable microcircuit since it will be recovered to a WO3 insulator by annealing in air at an appropriate temperature. The current study demonstrates a facile way to fabricate erasable WO3 conducting micro/nanowires, or even microcircuits, by selective hydrogenation under ambient conditions, which should be extended to other oxide materials for functional applications. [ABSTRACT FROM AUTHOR]

In the information explosion society, information security is highly demanded in the practical application, which raised a surge of interest in designing secure and reliable information transmission channels based on the inherent properties of emerging devices. Here, an innovative strategy to achieve the data encryption and reading during the data confidential transmission based on VO2 device is proposed. Owing to the specific insulator‐to‐metal transition property of VO2, the phase transitions between the insulator and metallic states are modulated by the combination of electric field, temperature, and light radiation. These external stimulus‐induced phase diagram is directly associated with the defined VO2 device, which are applicable for control the "0" or "1" electrical logic state for the information encryption. A prototype device is fabricated on an epitaxial VO2 film, which displayed a unique data encryption function with excellent stability. The current study not only demonstrated a multiphysical field‐modulated VO2 device for information encryption, but also supplied some clues for functional devices applications in other correlated oxide materials. [ABSTRACT FROM AUTHOR]

The utilization of clean hydrogen energy is becoming more feasible for the sustainable development of this society. Considering the safety issues in the hydrogen production, storage, and utilization, a sensitive hydrogen sensor for reliable detection is essential and highly important. Though various gas sensor devices are developed based on tin oxide, tungsten trioxide, or other oxides, the relatively high working temperature, unsatisfactory response time, and detection limitation still affect the extensive applications. In the current study, an amorphous tungsten trioxide (a‐WO3) layer is deposited on a phase‐change vanadium dioxide film to fabricate a phase transition controlled Pd/a‐WO3/VO2 hydrogen sensor for hydrogen detection. Results show that both the response time and sensitivity of the hydrogen sensor are improved greatly if increasing the working temperature over the transition temperature of VO2. Theoretical calculations also reveal that the charge transfer at VO2/a‐WO3 interface becomes more pronounced once the VO2 layer transforms to the metal state, which will affect the migration barrier of H atoms in a‐WO3 layer and thus improve the sensor performance. The current study not only realizes a hydrogen sensor with ultrahigh performance based on VO2 layer, but also provides some clues for designing other gas sensors with phase‐change material. [ABSTRACT FROM AUTHOR]

Aldosterone, which plays a central role in the regulation of blood pressure, is produced by zona glomerulosa (ZG) cells of the adrenal gland. When dysregulated, aldosterone is pathogenic and contributes to the development and progression of cardiovascular and renal disease. Although sustained production of aldosterone requires persistent [Ca.sup.2+] entry through low-voltage activated [Ca.sup.2+] channels, isolated ZG cells are considered nonexcitable, with recorded membrane voltages that are too hyperpolarized to permit [Ca.sup.2+] entry. Here, we show that mouse ZG cells within adrenal slices spontaneously generate membrane poten-tial oscillations of low periodicity. This innate electrical excitability of ZG cells provides a platform for the production of a recurrent [Ca.sup.2+] signal that can be controlled by Ang II and extracellular potassium, the 2 major regulators of aldosterone production. We conclude that native ZG cells are electrical oscillators, and that this behavior provides what we believe to be a new molecular explanation for the control of [Ca.sup.2+] entry in these steroidogenic cells., Introduction Autonomous overproduction of aldosterone, termed primary hyperaldosteronism (PA), is the most common form of endocrine hypertension (13% incidence), but among patients with resistant hypertension, its incidence increases substantially to [...]

G/[beta][gamma], a ubiquitous second messenger, relays external signals from G protein-coupled receptors to networks of intracellular effectors, including voltage-dependent calcium channels. Unlike high-voltage-activated [Ca.sup.2+] channels, the inhibition of low-voltage-activated [Ca.sup.2+] channels is subtype-dependent and mediated selectively by G[[beta].sub.2]-containing dimers. Yet, the molecular basis for this exquisite selectivity remains unknown. Here, we used pure recombinant G[beta][gamma] subunits to establish that the G[[beta].sub.2][[gamma].sub.2] dimer can selectively reconstitute the inhibition of [[alpha].sub.1H] channels in isolated membrane patches. This inhibition is the result of a reduction in channel open probability that is not accompanied by a change in channel expression or an alteration in active-channel gating. By exchanging residues between the active G[[beta].sub.2] subunit and the inactive G[[beta].sub.1] subunit, we identified a cluster of amino acids that functionally distinguish G[[beta].sub.2] from other G[beta] subunits. These amino acids on the [beta]-torus identify a region that is distinct from those regions that contact the G[alpha] subunit or other effectors. [alpha]-1H channels | channel regulation | G[beta][gamma] dimers

Manipulating the strain induced poly-domains and phase transition in a correlated oxide material is important for high performance device fabrication. Though the electronic transport in the strained oxide film at macroscopic scales can be directly measured, the anisotropic electronic state and the controllable phase separation cross the insulator-to-metal transition within nanoscale size are still elusive. Here, we selected a VO2 crystal film as prototypical oxide and achieved the manipulation of anisotropy electronic phase separation via injecting a He+ nanobeam into the VO2 film at room temperature. In addition, this nanoscale phase separation was directly visualized by infrared near-field imaging measurements, showing the pronounced and unique cR-axis dependent anisotropy on the VO2 surface. Our results offered insight toward understanding the anisotropic nanoscale phase separation in strained metal oxide films. [ABSTRACT FROM AUTHOR]