Characterization of follow-up chemical reactions by reverse pulse voltammetry. An analytical solution for spherical electrodes and microelectrodes

2013 ◽  
Vol 87 ◽  
pp. 416-424 ◽  
Author(s):  
A. Molina ◽  
E. Laborda ◽  
F. Martínez-Ortiz ◽  
E. Torralba ◽  
R.G. Compton
Keyword(s):  
Analytical Solution ◽  
Chemical Reactions ◽  
Reverse Pulse ◽  
Pulse Voltammetry

Reverse pulse voltammetry and polarography: a general analytical solution

1994 ◽  
Vol 72 (12) ◽  
pp. 2369-2377 ◽  
Author(s):  
Luis Camacho ◽  
Juan José Ruiz ◽  
Carmen Serna ◽  
Angela Molina ◽  
Francisco Martínez-Ortiz
Keyword(s):  
Analytical Solution ◽  
Numerical Solution ◽  
Arbitrary Power ◽  
Plane Electrode ◽  
General Analytical Solution ◽  
Reverse Pulse ◽  
Pulse Voltammetry

A rigorous analytical solution to reverse pulse techniques for a plane electrode expanding with an arbitrary power of time is presented. Our results include the plane approximation for SMDE as well as the expanding plane electrode model for DME. In the case of SMDE, our results have been contrasted with those obtained by numerical solution of the problem, obtaining identical results. Finally, we have compared our treatment with previous solutions in literature.

scholarly journals A closed-loop optogenetic screen for neurons controlling feeding in Drosophila

2021 ◽  
Author(s):  
Celia K S Lau ◽  
Meghan Jelen ◽  
Michael D Gordon
Keyword(s):  
Drosophila Melanogaster ◽  
Expression Pattern ◽  
Sensory Neurons ◽  
Closed Loop ◽  
Higher Order ◽  
Taste Detection ◽  
Proof Of Principle ◽  
Feeding Circuits

Abstract Feeding is an essential part of animal life that is greatly impacted by the sense of taste. Although the characterization of taste-detection at the periphery has been extensive, higher order taste and feeding circuits are still being elucidated. Here, we use an automated closed-loop optogenetic activation screen to detect novel taste and feeding neurons in Drosophila melanogaster. Out of 122 Janelia FlyLight Project GAL4 lines preselected based on expression pattern, we identify six lines that acutely promote feeding and 35 lines that inhibit it. As proof of principle, we follow up on R70C07-GAL4, which labels neurons that strongly inhibit feeding. Using split-GAL4 lines to isolate subsets of the R70C07-GAL4 population, we find both appetitive and aversive neurons. Furthermore, we show that R70C07-GAL4 labels putative second-order taste interneurons that contact both sweet and bitter sensory neurons. These results serve as a resource for further functional dissection of fly feeding circuits.

scholarly journals Proteinuria in COVID-19: prevalence, characterization and prognostic role

2021 ◽  
Author(s):  
Justine Huart ◽  
Antoine Bouquegneau ◽  
Laurence Lutteri ◽  
Pauline Erpicum ◽  
Stéphanie Grosch ◽  
...  
Keyword(s):  
Urinary Catheter ◽  
Single Center ◽  
Tubular Injury ◽  
Tubular Proteinuria ◽  
Prognostic Role ◽  
Urine Creatinine ◽  
Single Center Study ◽  
Center Study

Abstract Background Proteinuria has been commonly reported in patients with COVID-19. However, only dipstick tests have been frequently used thus far. Here, the quantification and characterization of proteinuria were investigated and their association with mortality was assessed. Methods This retrospective, observational, single center study included 153 patients, hospitalized with COVID-19 between March 28th and April 30th, 2020, in whom total proteinuria and urinary α1-microglobulin (a marker of tubular injury) were measured. Association with mortality was evaluated, with a follow-up until May 7th, 2020. Results According to the Kidney Disease Improving Global Outcomes staging, 14% (n = 21) of the patients had category 1 proteinuria (< 150 mg/g of urine creatinine), 42% (n = 64) had category 2 (between 150 and 500 mg/g) and 44% (n = 68) had category 3 proteinuria (over 500 mg/g). Urine α1-microglobulin concentration was higher than 15 mg/g in 89% of patients. After a median follow-up of 27 [14;30] days, the mortality rate reached 18%. Total proteinuria and urinary α1-microglobulin were associated with mortality in unadjusted and adjusted models. This association was stronger in subgroups of patients with normal renal function and without a urinary catheter. Conclusions Proteinuria is frequent in patients with COVID-19. Its characterization suggests a tubular origin, with increased urinary α1-microglobulin. Tubular proteinuria was associated with mortality in COVID-19 in our restropective, observational study.

scholarly journals Electrochemical Investigation of Curcumin–DNA Interaction by Using Hydroxyapatite Nanoparticles–Ionic Liquids Based Composite Electrodes

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4344
Author(s):  
Merve Uca ◽  
Ece Eksin ◽  
Yasemin Erac ◽  
Arzum Erdem
Keyword(s):  
Electrochemical Impedance ◽  
Differential Pulse ◽  
Dna Interaction ◽  
Composite Electrodes ◽  
Hydroxyapatite Nanoparticles ◽  
Graphite Electrodes ◽  
X Ray ◽  
Pulse Voltammetry ◽  
Polymerase Chain

Hydroxyapatite nanoparticles (HaP) and ionic liquid (IL) modified pencil graphite electrodes (PGEs) are newly developed in this assay. Electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and cyclic voltammetry (CV) were applied to examine the microscopic and electrochemical characterization of HaP and IL-modified biosensors. The interaction of curcumin with nucleic acids and polymerase chain reaction (PCR) samples was investigated by measuring the changes at the oxidation signals of both curcumin and guanine by differential pulse voltammetry (DPV) technique. The optimization of curcumin concentration, DNA concentration, and the interaction time was performed. The interaction of curcumin with PCR samples was also investigated by gel electrophoresis.

scholarly journals First Study of the Prevalence and Characterization of Brachial Plexus Injuries in Guatemala

2021 ◽  
Vol 16 (01) ◽  
pp. e46-e50
Author(s):  
Carmen Joanna González Lemus ◽  
Fernando Xavier Romero Prieto
Keyword(s):  
Brachial Plexus ◽  
Brachial Plexus Injury ◽  
Main Mode ◽  
Cross Sectional ◽  
Speed Up ◽  
Male Patients ◽  
Mode Of Transportation ◽  
Surgery Department

Abstract Objective This study aimed to estimate the prevalence of brachial plexus injuries and to characterize clinically and epidemiologically patients with brachial plexus injury. Materials and Methods In this cross-sectional descriptive study, 2,923 medical records of patients aged 1 to 64 years who presented at outpatient peripheral nerve unit of the Orthopedic Surgery Department of Hospital Roosevelt, Guatemala, from January 2017 to December 2017, were prospectively analyzed to identify the prevalence and factors associated with brachial plexus injuries. Results The prevalence rate of brachial plexus injuries in patients was 5.74%. This injury is more common in men (90.5%) aged 24 to 64 years. Brachial plexus injuries occurred secondary to motorcycle accident in 72% of the cases, with the majority affecting the dominant upper extremity. In addition, 64.28% of the patients took 1 to 6 months to seek consultation, whereas only 16.07% requested medical assistance <1 month from the onset of symptoms, and this result was associated with early diagnosis and adequate recovery during follow-up. Furthermore, 66.67% presented upper brachial plexus injury with no associated fractures or vascular injury, manifesting distress while performing daily activities that required hand, arm, and elbow movements. Conclusion The risk of suffering BPIs in Guatemala increases in economically active male patients that use motorcycles as main mode of transportation. Patients should consult immediately after injury onset to optimize management results. For this reason, hospitals must develop specialized clinical guidelines to speed up the identification and treatment of BPI injuries.

Post-Operative Dysphagia in Anterior Cervical Discectomy and Fusion

2021 ◽  
pp. 000348942110155
Author(s):  
Leonard Haller ◽  
Khush Mehul Kharidia ◽  
Caitlin Bertelsen ◽  
Jeffrey Wang ◽  
Karla O’Dell
Keyword(s):  
Risk Factors ◽  
Medical Records ◽  
Assessment Tool ◽  
Demographic Data ◽  
Anterior Cervical Discectomy ◽  
Cervical Discectomy ◽  
Long Term Follow Up

Objective: We sought to identify risk factors associated with long-term dysphagia, characterize changes in dysphagia over time, and evaluate the incidence of otolaryngology referrals for patients with long-term dysphagia following anterior cervical discectomy with fusion (ACDF). Methods: About 56 patients who underwent ACDF between May 2017 to February 2019 were included in the study. All patients were assessed for dysphagia using the Eating Assessment Tool (EAT-10) survey preoperatively and late postoperatively (≥1 year). Additionally, 28 patients were assessed for dysphagia early postoperatively (2 weeks—3 months). Demographic data, medical comorbidities, intraoperative details, and post-operative otolaryngology referral rates were collected from electronic medical records. Results: Of the 56 patients enrolled, 21 patients (38%) had EAT-10 scores of 3 or more at long-term follow-up. None of the demographics, comorbidities, or surgical factors assessed were associated with long-term dysphagia. Patients who reported no long-term dysphagia had a mean EAT-10 score of 6.9 early postoperatively, while patients with long-term symptoms had a mean score of 18.1 ( P = .006). Of the 21 patients who reported persistent dysphagia symptoms, 3 (14%) received dysphagia testing or otolaryngology referrals post-operatively. Conclusion: Dysphagia is a notable side effect of ACDF surgery, but there are no significant demographics, comorbidities, or surgical risk factors that predict long-term dysphagia. Early postoperative characterization of dysphagia using the EAT-10 questionnaire can help predict long-term symptoms. There is inadequate screening and otolaryngology follow-up for patients with post-ACDF dysphagia.

Sign in / Sign up

Export Citation Format

Share Document