24 research outputs found
N7-(carboxymethyl)guanine-lithium crystalline complex: a bioinspired solid electrolyte
Electrochemical device with components having direct significance to biological life processes is a potent futuristic strategy for the realization of all-round green and sustainable development. We present here synthesis design, structural analysis and ion transport of a novel solid organic electrolyte (G7Li), a compound reminiscent of ion channels, derived from regioisomeric N7-guanine-carboxylate conjugate and Li-ions. G7Li, with it\u27s in-built supply of Li(+)-ions, exhibited remarkably high lithium-ion transference number (= 0.75) and tunable room temperature ionic conductivity spanning three decades (≈10(-7) to 10(-3) Ω(-1) cm(-1)) as a function of moisture content. The ionic conductivity show a distinct reversible transition around 80-100 °C, from a dual Li(+) and H(+) (<100 °C) to a pure Li(+) conductor (>100 °C). Systematic studies reveal a transition from water-assisted Li-ion transport to Li hopping-like mechanism involving guanine-Li coordination. While as-synthesized G7Li has potential in humidity sensors, the anhydrous G7Li is attractive for rechargeable batteries
Renal sympathetic nervous system and the effects of denervation on renal arteries
UA Open Access Publishing FundResistant hypertension is associated with chronic activation of the sympathetic nervous system resulting in various comorbidities. The prevalence of resistant hypertension is often under estimated due to various reasons. Activation of sympathetic nervous system at the renal- as well as systemic- level contributes to the increased level of catecholamines and resulting increase in the blood pressure. This increased activity was demonstrated by increased muscle sympathetic nerve activity and renal and total body noradrenaline spillover. Apart from the hypertension, it is hypothesized to be associated with insulin resistance, congestive heart failure and obstructive sleep apnea. Renal denervation is a novel procedure where the sympathetic afferent and efferent activity is reduced by various techniques and has been used successfully to treat drug-resistant hypertension improvement of various metabolic derangements. Renal denervation has the unique advantage of offering the denervation at the renal level, thus mitigating the systemic side effects. Renal denervation can be done by various techniques including radiofrequency ablation, ultrasound guided ablation and chemical ablation. Various trials evaluated the role of renal denervation in the management of resistant hypertension and have found promising results. More studies are underway to evaluate the role of renal denervation in patients presenting with resistant hypertension in different scenarios. Appropriate patient selection might be the key in determining the effectiveness of the procedure.This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Ion Channel-like Crystallographic Signatures in Modified Guanine–Potassium/Sodium Interactions
This communication describes crystallographic details
of structures
reminiscent of ion channels, formed from regioisomeric N7 and N9 guanine-carboxylate
conjugates with potassium/sodium ions and their subsequent STM observations
on Au(111) surface. Ion channel-like crystal structures were obtained
with the observation of a notable shift in metal ion coordination
from carbonyl to carboxylate oxygen. These results are expected to
provide insight into competing sites for modified guanine–metal
coordination, an entry into guanine-based ion channels and a route
toward guanine-functionalized surfaces
MYXEDEMA COMA WITH MYXEDEMA HEART DISEASE
There was rapid clinical worsening with acute renal failure requiring continuous renal replacement therapy, acute respiratory failure requiring mechanical ventilation, and persistent hypotension requiring inotropic support with dobutamine and epinephrine