Function and interaction of coronavirus ion channel proteins

Objective: COVID-19 has emerged as a significant global health crisis causing devastating effects on world population accounting for over 6 million deaths worldwide. Although acute RTI is the prevalent cause of morbidity, kidney outcomes centered on a spectrum of AKI have evolved over the course of the pandemic. Especially the emerging variants have posed a daunting challenge to the scientific communities, prompting an urging requirement for global contributions in understanding the viral dynamics. In addition to canonical genes, several subgroup- specific accessory genes are located between the S and E genes of coronaviruses regarding which little is known. Previous studies have shown that accessory proteins (aps) in viruses function as viroporins that regulate viral infection, propagation and egress [1]. In this study we attempted to characterize the function of aps of coronavirus variants as ion channels. Furthermore, we also probed the interaction of ap4 with the host system. Method(s): Serial passaging (selection pressure), growth kinetics, confocal imaging, genome sequence analysis and proteomics were performed in Huh-7, MRC5 cells and/or human monocyte derived macrophages. Potassium uptake assay was performed in a Saccharo myces cerevisiae strain, which lacks the potassium transporters trk1 and trk2. Ion conductivity experiments were performed in Xenopus laevis oocytes using Two Electrode Voltage Clamp (TEVC) method. Result(s): Serial passaging demonstrated the acquisition of several frameshift mutations in ORF4 resulting in C-terminally truncated protein versions (ap4 and ap4a) and indicate a strong selection pressure against retaining a complete ORF4 in vitro. Growth kinetics in primary cells illustrated a reduction of viral titers when the full-length ap4 was expressed compared to the C-terminally truncated protein ap4a. Confocal imaging showed that ap4 and ap4a are not exclusively located in a single cellular compartment. Potassium uptake assay in yeast and TEVC analyses in Xenopus oocytes showed that ap4 and ap4a act as a weak K+ selective ion channel. In addition, accessory proteins of other virus variants also elicited microampere range of currents. Conclusion(s): Our study provides the first evidence that ap4 and other accessory proteins of coronavirus variants act as viroporins. Future studies are aimed at demonstrating the role of ap4 during the viral life cycle by modulating ion homeostasis of host cell in vivo (interacting proteins obtained from proteomic studies) and thereby serve as a tool for potential drug target.

Spectrum of Biochemical Alterations in Patients with Covid-19

Background and objective: Millions of people worldwide have died from COVID-19, which has caused the failure of the lungs and other organs. The research assessed biochemical anomalies in COVID-19 patients to comprehend the illness and its effect better. Study Design: Retrospective longitudinal cohort analysis Place of study: ABWA Medical College Faisalabad Methods: A total of 150 adult patients (n=150) who tested positive for COVID-19 via RT-PCR were included in the study. A Roche Diagnostics Cobas C501 used spectrophotometry to measure calcium, magnesium, phosphate, lactate dehydrogenase (LDH), urea, creatinine, ferritin, and chloride in the blood. A NOVA electrolytic analyzer used Ion-selective electrodes to measure sodium, chloride, potassium, and bicarbonate. Result(s): In the study, 33.6% of patients had elevated urea levels, and 22.4% had elevated creatinine levels. Furthermore, 88.8% of patients had elevated ferritin levels, and 93.5% had elevated LDH levels. After 44 weeks, there was a drop in sodium-containing electrolytes, with 9% of patients experiencing a decrease in sodium, 22.4% in potassium, 53.3% in bicarbonate, 48.6% in calcium, and 23.4% in phosphorus. These changes in electrolyte levels suggest a long-term trend in electrolyte depletion among the patient population. There was no significant difference in biochemical anomalies between age groups (p > 0.05). Conclusion(s): These results suggest that COVID-19 patients have lung illness and multi-organ involvement, which should be considered when managing these patients. These biochemical alterations warrant careful monitoring for organ failure by healthcare practitioners. More study is required to comprehend the processes causing these biochemical anomalies in COVID-19 patients.Copyright © 2023 Lahore Medical And Dental College. All rights reserved.

Preparation of a novel poly-(di-ionic liquid)/BDD-modified electrode for the detection of tetrachloro-p-benzoquinone.

During the COVID-19 pandemic, the release of toxic disinfection by-products (DBPs) has increased due to the intensive, large-scale use of disinfectants. Halogenated benzoquinones (HBQs) are among the most toxic DBPs, but there is no rapid, convenient, and economical detection method. In this study, a novel PDIL/BDD-modified electrode was prepared in a mixed solvent of dimethyl sulfoxide (DMSO) and acetonitrile (ACN) by electrochemical polymerization with a di-ionic ionic liquid containing alkenyl groups as the monomer. The electrochemical behavior of tetra-chloro-p-benzoquinone (TCBQ) on the modified electrode was studied. By studying the cyclic voltammetry behavior of TCBQ on the PDIL/BDD electrode, it was concluded that the electrode reactions of TCBQ included the reduction of TCBQ to TCBQH2 (C1) and the reduction of bis-quinhydrone imidazole π-π type charge transfer complex to TCBQH2 (C2). By studying the SWV responses of TCBQ in the concentration range of 1-100 ng/L on the PDIL/BDD electrode, it was found that the reduction peak current (Ipa) had a linear relationship with the concentration. The electrochemical SWV technique was used to detect the concentration of trace TCBQ in water and is expected to be used for the detection of other HBQs in drinking water and swimming pool water.

COVID-19 impedimetric biosensor based on polypyrrole nanotubes, nickel hydroxide and VHH antibody fragment: specific, sensitive, and rapid viral detection in saliva samples.

SARS-CoV-2 rapid spread required urgent, accurate, and prompt diagnosis to control the virus dissemination and pandemic management. Several sensors were developed using different biorecognition elements to obtain high specificity and sensitivity. However, the task to achieve these parameters in combination with fast detection, simplicity, and portability to identify the biorecognition element even in low concentration remains a challenge. Therefore, we developed an electrochemical biosensor based on polypyrrole nanotubes coupled via Ni(OH)2 ligation to an engineered antigen-binding fragment of heavy chain-only antibodies (VHH) termed Sb#15. Herein we report Sb#15-His6 expression, purification, and characterization of its interaction with the receptor-binding domain (RBD) of SARS-CoV-2 in addition to the construction and validation of a biosensor. The recombinant Sb#15 is correctly folded and interacts with the RBD with a dissociation constant (KD) of 27.1 ± 6.4 nmol/L. The biosensing platform was developed using polypyrrole nanotubes and Ni(OH)2, which can properly orientate the immobilization of Sb#15-His6 at the electrode surface through His-tag interaction for the sensitive SARS-CoV-2 antigen detection. The quantification limit was determined as 0.01 pg/mL using recombinant RBD, which was expressively lower than commercial monoclonal antibodies. In pre-characterized saliva, both Omicron and Delta SARS-CoV-2 were accurately detected only in positive samples, meeting all the requirements recommended by the World Health Organization for in vitro diagnostics. A low sample volume of saliva is needed to perform the detection, providing results within 15 min without further sample preparations. In summary, a new perspective allying recombinant VHHs with biosensor development and real sample detection was explored, addressing the need for accurate, rapid, and sensitive biosensors.

Current Advances in Nanomaterial-associated Micro and Nano-devices for SARS-CoV-2 Detection

COVID-19 spread rapidly around the world in 18 months, with various forms of variants caused by severe acute respiratory syndrome (SARS-CoV). This has put pressure on the world community and created an urgent need for understanding its early occurrence through rapid, simple, cheap, and yet highly accurate diagnosis. The most widely adopted method as of today is the real-time reverse-transcriptase polymerase chain reaction. This test has shown the potential for rapid testing, but unfortunately, the test is not rapid and, in some cases, displays false negatives or false positives. The nanomaterials play an important role in creating highly sensitive systems, and have been thought to significantly improve the performance of the SARSCoV- 2 protocols. Several biosensors based on micro-and nano-sensors for SARS-CoV-2 detection have been reported, and they employ multi-dimensional hybrids on sensing surfaces with devices having different sizes and geometries. Zero-to-three-dimension nanomaterial hybrids on sensing surfaces, including nanofilm hybrids for SARS-CoV-2 detection, were employed with unprecedented sensitivity and accuracy. Furthermore, the sensors were nanofluidic and mediated high-performance SARS-CoV-2 detection. This breakthrough has brought the possibility of making a biosystem on a chip (Bio-SoC) for rapid, cheap, and point-of-care detection. This review summarises various advancements in nanomaterial-associated nanodevices and metasurface devices for detecting SARS-CoV-2.

Effect of Neurofeedback Training on male Swimmers' Stress Tolerance

This study aimed to analyze the effect of eight weeks of neurofeedback training to increase the stress tolerance level of swimmers the current researchers examined six all-India inter-university male swimmers. For the pre-test and post-test data on stress tolerance of swimmers, the current author used the computer-based, pre-designed "Determination Test" on the Schuhfried "Vienna Test System", and the alpha and beta training was provided by the pre-designed Med-Life biofeedback/neurofeedback system. Swimmers go-through under rigorous training cycle andat the time of the race, and to reduce that stress, the current author conducted this study on swimmers and found the difference in the mean of the pre-test, i.e., 27.67, while the post-test mean was 59.5;hence, the value of the t-statistic(5.338) is also significant to its corresponding p-value, i.e., 0.003, which is less than 0.05, which shows the significant difference between the pre-test and post-test, thus leading the current authors conclude that there was a significant improvement in the swimmers' perception of their stress tolerance level and, it shows that the 21 tutelage sessions were effective in increasing the swimmers' stress tolerance level, which can help the swimmers maintain an optimal state at the time of the race.Copyright © 2023, Anka Publishers. All rights reserved.

Comprehensive Program of Neurotherapy for a Visual Artist with Post-Covid-19 Syndrome Following Sars-Cov-2 Infection and Severe Course of Covid-19 Treated in Long-Term Pharmacologically Induced Coma

Background: Case study: Conclusion(s): The purpose of the study was twofold: (1) to present post-COVID-19 syndrome, which involves a variety of ongoing neurological, neuropsychiatric, neurocognitive, emotional and behavioral disorders resulting from SARS-CoV-2 infection followed by a severe course of COVID-19 treated in long term pharmacologically induced coma in a visual artist, which impacted on her artwork;(2) to present QEEG/ERP results and neuropsychological testing results in the evaluation of the effectiveness of a comprehensive neurotherapy program, with individualized EEG-Neurofeedback, and art-therapy in the reduction of post-COVID-19 syndrome in this artist. Ms. G., 42, a visual artist, portraitist, with good health, became ill in May 2022. Allegedly flu symptoms appeared first. After a few days, shortness of breath joined in. The PCR test for SARS-CoV-2 was positive. The patient was hospitalized, referred to the ICU, put on a respirator and treated over 11days of a pharmacologically induced coma. Two months after leaving hospital the patient developed post-COVID-19 syndrome. She was diagnosed by an interdisciplinary team: a neurologist, neuropsychiatrist and neuropsychologist. A PET scan of her brain revealed extensive changes involving a loss of metabolism in various brain areas. The presence of complex post-COVID, neurological, neuropsychiatric, neurocognitive, emotional and behavioral disorders was found and a neuropsychiatrist suggested a diagnosis of post-COVID schizophrenia. She was refered to the Reintegration and Training Center of the Polish Neuropsychological Society.We tested the working hypothesis as to the presence of schizophrenia and there was no reduction in the difference of ERPs waves under GO/NOGO task conditions, like in the reference group with schizophrenia (see also Pachalska, Kaczmarek and Kropotov 2021). The absence of a functional neuromarker for schizophrenia allowed us to exclude this diagnosis and to propose a new disease entity, that being post-COVID-19 syndrome. She received a comprehensive two-component program of neurotherapy: (1) program A consisting in goal-oriented neuropsychological rehabilitation, including art therapy (see also: Pachalska 2008;2022b), and (2) program B, based on the most commonly used form of EEG-Neurofeedback: frequency/ power EEG-Neurofeedback, using 2 bipolar surface electrodes, with the protocols written for her specific needs (see also Thompson & Thompson 2012;Kropotov 2016). The comprehensive neurotherapy program lasted 10 weeks, EEG Neurofeedback and art therapy classes were conducted 3 times a week for 45 minutes each. We found that after the completion of the comprehensive neurotherapy program there was a statistically significant reduction in high beta activity compared to the normative HBI database, which is associated with a reduction of anxiety. Also, we observed the improvement of neurocognitive functioning in neuropsychological testing (a significant reduction of anxiety and a noticeable improvement in neurocognitive functions). It should be stressed that the artist was happy that she had regained the ability to create, and even sells her artwork, although her style of painting had changed. Almost all the neurological, psychiatric, neurocognitive, emotional and behavioral disturbances, were reduced in their severity. The artist showed marked improvement and was able to return to painting. The artwork she produced after her illness is in high demand with art collectors. It can be also helpful in the reintegration of the Self System, and the improvement in her quality of life. Human Brain Index (HBI) methodology might be very useful in diagnosing and developing therapies for patients with post-COVID-19 syndrome.Copyright © 2023, MEDSPORTPRESS Publishing House. All rights reserved.

What the Eye Cannot See: A Case of Persistent Altered Mental Status in a Patient With Cholestatic Liver Disease?

Introduction: Altered mental status (AMS) is a common symptom in patients with liver disease with a wide list of differential diagnoses. Knowledge of etiologies of AMS unique to patients with hepatic dysfunction is vital in order to help recognize, diagnose, and treat the underlying cause in a timely manner. Case Description/Methods: A 46-year-old man with a history of recent COVID infection was transferred to our hospital for further evaluation of acute liver injury and AMS. On arrival, his labs were notable for AST of 408 U/L, ALT of 620 U/L, ALP of 5942 U/L, TB of 11.0 mg/dL, and an INR of 1.1. His work-up included an MRCP that showed segmental biliary ductal dilation with associated restricted diffusion and peribiliary enhancement concerning for sclerosing cholangitis. ERCP revealed a 3cm biliary cast that was removed and noted diffuse rarefaction of ducts throughout the entire biliary tree. A liver biopsy revealed centrizonal cholestasis with portal-based bile ductular reaction and mild bile duct injury. Despite adequate treatment of suspected infection and hepatic encephalopathy, his AMS persisted. His basic metabolic panel (BMP) was notable for Na of 143 mEq/L. A send-out lipid panel that was obtained to work-up his dyslipidemia revealed a total cholesterol of 1018 mg/dL, triglycerides of 420mg/dL, and the presence of lipoprotein X. A venous blood gas (VBG) was obtained showing a Na of 157 mEq/L and serum osmolality was 322 mmol/kg, confirming true hypernatremia. He was slowly treated with hypotonic solutions with significant improvement in his mentation. On follow-up one year later, he has persistent cholestasis and is currently being considered for liver transplant. Discussion(s): The final diagnosis was COVID-related ischemic cholangitis and disappearing bile ducts with persistent cholangiopathy, presenting with severe cholestasis, accumulation of lipoprotein X, and pseudonormonatremia. When faced with severe cholestatic liver disease, clinicians should keep in mind the possibility of accumulation of lipoprotein X and its association with hyperviscosity and spurious electrolyte abnormalities. Clinicians should rely on obtaining blood gas analyses for accurate electrolyte measurement in such cholestatic patients as blood gas analyses utilize direct ion-sensitive electrodes (ISE) to measure electrolytes, whereas routine basic metabolic panels utilize indirect ISE that are liable to spurious results in the presence of hyperlipoproteinemia/lipoprotein X.

Multiple Electrode Aggregometry (Multiplate): Functional Assay for Vaccine-Induced (Immune) Thrombotic Thrombocytopenia (VITT).

Vaccine-induced immune thrombotic thrombocytopenia (VITT) was first described in 2021 and represents an adverse reaction to adenoviral vector COVID-19 vaccines AstraZeneca ChAdOx1 nCoV-19 (AZD1222) and Johnson & Johnson Ad26.COV2.S vaccine. VITT is a severe immune platelet activation syndrome with an incidence of 1-2 per 100,000 vaccinations. The features of VITT include thrombocytopenia and thrombosis within 4-42 days of first dose of vaccine. Affected individuals develop platelet-activating antibodies against platelet factor 4 (PF4). The International Society on Thrombosis and Haemostasis recommends both an antigen-binding assay (enzyme-linked immunosorbent assay, ELISA) and a functional platelet activation assay for the diagnostic workup of VITT. Here, the application of multiple electrode aggregometry (Multiplate) is presented as a functional assay for VITT.

Supraclavicular regional anaesthesia affecting bispectral index as level of consciousness monitor (SUPRABLOC): a pilot randomised controlled trial

Background: Renewed interest in regional anaesthesia during the recent COVID-19 pandemic has inspired application of neuraxial anaesthesia for previously unconventional indications, such as awake abdominal surgeries. These patients needed little sedation, since studies demonstrate that neuraxial anaesthesia causes sedation as measured by the bispectral index (BIS). In contrast, no published study has investigated the possible sedative effects of non-neuraxial regional anaesthesia. This pilot randomised controlled trial (RCT) was designed as a template for, and to test the feasibility of, performing a definitive RCT to establish if non-neuraxial regional anaesthesia has any sedative effect. Method(s): Forty participants presenting for forearm surgery were randomly allocated to two treatment groups (supraclavicular block and control). Their level of sedation was monitored with BIS prior to surgery for 60 minutes. Specific feasibility outcomes were planned and data were collected according to CONSORT 2010 recommendations. Result(s): Out of 48 patients screened, 41 (85.42%) were invited to participate. Forty patients (97.56%) consented and 100% of these completed the study. In four participants (10%), BIS electrodes needed replacement, while inadequate contact was shown in three participants (7.50%). Data collection and form completion were deemed "easy" and block success rate was 100%. Differences in mean BIS between groups were < 5 and a difference of 10% between groups in incidence of BIS < 80 (85% block group, 75% control group) was shown. Conclusion(s): We propose that progression to formal RCT is feasible only with specific modifications to the study design. The decrease in BIS value from baseline should be measured per patient and a clinically significant decrease should be estimated;emergency patients should be excluded;the sample size should be 500 patients;and multiple trial sites should be used. Further consideration should be given to whether such a trial would provide clinically useful information, and would justify the risks, patient discomfort and the considerable financial cost.Copyright © 2023, Medpharm Publications. All rights reserved.

Development of Aptasensor for the Diagnosis of Covid-19

Objectives: The objective is to develop a low-cost, practical, portable aptasensor platform for the diagnosis of COVID-19. Materials -Methods: Amino-terminated aptamers to be used for the design of an aptasensor were synthesized by SELEX method, and interaction of aptamers with SARS-CoV-2 S1 protein was investigated by isothermal titration calorimetry (ITC). Gold electrodes were used to design the biosensor platform. After the electrode surface was functionalized with cysteamine, the amino-terminated aptamer was conjugated to the surface via glutaraldehyde crosslinker. Then, the surface characterization and analytical parameters of the designed sensing platform were determined by adding commercial S1 proteins on the surface using differential pulse voltammetry (DPV), cyclic voltammetry (CV) and impedance spectroscopy (EIS). To evaluate the working performance of the system, S1 proteins were added to the synthetic serum samples using the standard addition method and the measurements were repeated. Result(s): Surface characterization of the platform designed with EIS and CV measurements was performed and it was found that the modification was successfully performed. In addition, DPV results and analytical parameters of the platform (calibration plot, limit of detection(LOD) , repeatability, coefficient of variation) were determined and the working performance of system was evaluated. Moreover, working performance of the biosensor in real samples and its specificity for COVID -19 were determined by experiments with synthetic serum and influenza A and B proteins. Conclusion(s): According the results, the system has potential to be used for the detection of COVID -19, and also it can be rapidly adapted in different pandemic situations that may occur in the future.

Successful hysteroscopic management of two cases of interstitial pregnancy

Introduction. Interstitial pregnancy (IP) is the rarest type of tubal pregnancy with a high rupture rate and often remains asymptomatic in the first 10-12 gestational weeks. Therefore, the timing of the diagnosis is crucial for successful management. Case report. Two patients, aged 28 and 22, were diagnosed with IP using transvaginal ultrasound. Both patients were asymptomatic, with initial serum betahCG of 6,664 mIU/mL and 4,641 mIU/mL, respectively. Since they refused treatment with methotrexate and wanted to preserve their fertility, we performed operative hysteroscopy with resection and evacuation of the gestational tissue. The procedures were uneventful. The betahCG levels dropped significantly, and the patients were discharged after three and four hospital days, respectively. Conclusion. Using hysteroscopic procedures, we successfully treated two asymptomatic patients with IP of gestational age < 10 weeks by ultrasonography and levels of serum betahCG < 7,000 mIU/mL. With the occurrence of IP but also the numerous advantages of hysteroscopy, large, multicenter studies are necessary to further investigate the place of this approach as a single treatment method for IP. Trends and consequences observed during the COVID-19 pandemic correlate with the importance of timely diagnosis of ectopic pregnancies, the benefits of a minimally invasive approach in their treatment, and epidemiologically justified shorter hospital stays.Copyright © 2023 Inst. Sci. inf., Univ. Defence in Belgrade. All rights reserved.

Have newborn hearing screening programs been affected by the COVID-19 pandemic?

Introduction: Due to the vital importance of early diagnosis and intervention of congenital hearing loss, the aim of this study was to compare the rate of newborn hearing screening before and after the COVID-19 pandemic quarantine. Material(s) and Method(s): In this study, the data related to 6144 newborns during two 18-month time periods before and after the onset of the COVID-19 pandemic quarantine, was analyzed. Result(s): From all visited newborns, 3770 and 2374 referred to the centre before and after the COVID-19 pandemic quarantine, respectively. There were statistically significant differences in the results of screening and the referral rate of neonates before and after the pandemic (p = 0.00). The results showed that both the residents of urban and rural regions visited for newborn hearing screening less frequently after the onset of the pandemic, but no statistically significant difference was shown between the number of boys and girls before and after the pandemic (p = 0.72). Conclusion(s): Our results help gain new insights regarding the impacts of disruptive events such as pandemics on the implementation of health screening programs. Boosting public knowledge by providing families with proper education appears to be helpful in preventing the negative effects of delayed implementation of health screening programs.Copyright © 2022 International Association of Physicians in Audiology.

Po251 / #854 Noninvasive Closed Loop Diaphragm Stimulation for Ventilated Icu Patients: E-Poster Viewing

Introduction: Many COVID-19 patients need prolonged artificial ventilation. Skeletal muscle wastes rapidly when deprived of neural activation, and in ventilated patients the diaphragm muscle begins to atrophy within 24 hours (ventilator induced diaphragmatic dysfunction, VIDD). This profoundly weakens the diaphragm, complicating the weaning of the patient off the ventilator, and increasing the risk of complications such as bacterial pneumonia. 40% of the total duration of mechanical ventilation in ITU patients is accounted for by the weaning period, after the initial illness has resolved. Prevention of VIDD would therefore both improve individual outcomes, and also release ITU capacity. We aim to prevent VIDD by exercising the diaphragm with electrical stimulation of the nerves that control it. Evidence suggests that muscle wasting can be prevented by quite low levels of exercise (e.g. 200 contractions per day). Materials / Methods: The diaphragm is activated by the phrenic nerves, formed from branches of the C3-C5 nerve roots in the neck. These nerves may be electrically stimulated in the lower neck. An electrode array is positioned on each side of the neck using surface landmarks. The system automatically determines the best electrode to use in each array. Sensors built into the ventilatory circuit are monitored both to match stimulation to the respiratory cycle and to determine the effects of stimulation. Result(s): We have designed and built a prototype system for unsupervised noninvasive phrenic nerve stimulation. The system delivers one contraction every 7 minutes, synchronised to early inspiration so as not to disrupt ventilation. Electrode impedances are measured before each stimulus, and the closed loop system continuously monitors the effects of stimulation on airflow and adjusts stimulation parameters to compensate for changes in coupling, for example due to head movement. Discussion(s): This stimulator system overcomes several limitations of existing solutions, namely the resource implications and risk profile of invasive electrodes, and the requirement for supervised operation. While invasive systems are applied selectively for these reasons, routine use of our system can be envisaged. This system was inspired by COVID-19 patients but is not limited to them, and has broad applicability to ventilated intensive care patients in general, for example patients with traumatic brain injury. Conclusion(s): Non-invasive stimulation of the phrenic nerves using pressure-free skin surface electrodes is feasible and safe. It offers the potential for prevention of VIDD and thereby faster ventilator weaning and shorter stay on ITU. Clinical trials are planned in 2022. Learning Objectives: After this presentation delegates should be aware of: 1. Ventilation induced diaphragm dysfunction (VIDD) and its importance in patients having lengthy periods of ventilation, as in many cases of COVID-19. 2. The fact that low levels of activity can maintain the condition of skeletal muscles including the diaphragm muscle 3. The potential for noninvasive stimulation of the phrenic nerves to provide 'diaphragm exercise' and prevent VIDD. Keywords: phrenic nerve stimulation, diaphragm, ventilation, COVID-19Copyright © 2022

Influence of Nitrogen-Doped Carbon Dot and Silver Nanoparticle Modified Carbon Paste Electrodes on the Potentiometric Determination of Tobramycin Sulfate: A Comparative Study

Two inexpensive and simple methods for synthesis of carbon nanodots were applied and compared to each other, namely a hydrothermal and microwave-assisted method. The synthesized carbon nanodots were characterized using transmission electron microscopy (TEM), ultraviolet-visible (UV-Vis), photoluminescence (PL), Fourier transform-infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The synthesized microwave carbon nanodots had smaller particle size and were thus chosen for better electrochemical performance. Therefore, they were used for our modification process. The proposed electrodes performance characteristics were evaluated according to the IUPAC guidelines, showing linear response in the concentration range 10−6–10−2, 10−7–10−2, and 10−8–10−2 M of tobramycin with a Nernstian slope of 52.60, 58.34, and 57.32 mV/decade for the bare, silver nanoparticle and carbon nanodots modified carbon paste electrodes, respectively. This developed potentiometric method was used for quantification of tobramycin in its co-formulated dosage form and spiked human plasma with good recovery percentages and without interference of the co-formulated drug loteprednol etabonate and excipients.

Fe(VI) activation system mediated by a solar-driven TiO2 nanotubes electrode for CLQ degradation: Performances, mechanisms and pathways.

Ferrate (Fe(VI), FeO42-) has been widely used in the degradation of micropollutants with the advantages of high redox potential, no secondary pollution and inhibition of disinfection byproducts. However, the low transformation of Fe(V) and/or Fe(IV) by Fe(VI) and incomplete mineralization of pollutants limit their application. In this work, we designed a photo electric cell with TiO2 nanotubes (TNTs) and Pt serving as the anode and cathode to enhance the utilization of Fe(VI) (Fe(VI)-TNTs system). TNTs accelerated the generation of •OH via hVB+ oxidation of OH- and photogenerated electrons at Pt boosted the transformation of Fe(VI) to Fe(V) and/or Fe(IV), resulting in a 22.2 % enhancement of chloroquine (CLQ) removal compared to Fe(VI) alone. The results from EPR and quenching tests showed that Fe(VI), Fe(V), Fe(IV), •OH, O2•- and hVB+ coexisted in the Fe(VI)-TNTs system, among which Fe(V) and Fe(IV) were testified as the primary reactive substances accounting for 59 % of CLQ removal. The performance tests and recycling tests demonstrated that the Fe(VI)-TNTs system maintained excellent performance in an authentic water environment. The plausible degradation pathway of CLQ oxidized in the Fe(VI)-TNTs system was proposed with nine identified oxidation products via N-C cleavage, electrophilic addition and carboxylation processes. Based on the ECOSAR calculation, the constructed reaction system allowed a decrease in acute and chronic toxicity. Our findings provide a highly efficient and cost-effective strategy to enhance Fe(VI) application for micropollutant degradation in the future.

Voltammetric Determination of Favipiravir Used as an Antiviral Drug for the Treatment of Covid-19 at Pencil Graphite Electrode.

This work describes the sensitive voltammetric determination of favipiravir (FAV) based on its reduction for the first time with a low-cost and disposable pencil graphite electrode (PGE). In addition, the determination of FAV was also performed based on its oxidation. Differential pulse (DP) voltammograms recorded in 0.5 M H2SO4 for the reduction of FAV show that peak currents increase linearly in the range of 1.0 to 600.0 µM with a limit of detection of 0.35 µM. The acceptable recovery values (98.9-106.0 %) obtained from a pharmaceutical tablet, real human urine, and artificial blood serum samples spiked with FAV confirm the high accuracy of the proposed method.

Comparative Study of Serum Electrolytes in Covid-19 and Healthy Patients in Tertiary Care Center, Karimnagar

Introduction- Electrolyte balance of the body is maintained by renin angiotensin aldosterone system. Some previous studies suggested that COVID-19 is associated with gastrointestinal symptoms, such as diarrhea and vomiting. This may results in electrolyte disturbances in patients. Electrolytes in body like sodium (Na), potassium (K). Chloride (Cl) plays an important physiological role in maintaining acid base and water balance of cells of the body. Aims and objectives: Our study aimed to compare some electrolyte between covid 19 and non-covid patients retrospectively. Material(s) and Method(s): This retrospective study included total 57 males and 43 females in the age group of 28 to 65 years. The results were compared with 100 age and sex matched healthy controls. Estimation of serum electrolytes was done with the collected venous blood samples using the ion selective electrode technique in an electrolyte analyzer. Analysis was done using SPSS V 25 Software. Chi-square and t-test were used to see association and difference between two variable respectively. Result(s): We have found that covid 19 is associated with low levels of electrolytes like Na, K, Cl. Chloride levels in both the groups was not statistically significant. But Hyponatremia and Hypokalemia were observed in cases group with high statical Signficance. Conclusion(s): Study found that electrolytes deterioration in these patients play a critical role in patients management. Thus a monitoring of electrolyte is essential throughout their illness to manage covid patients to improve their quality of life.Copyright © 2020 Ubiquity Press. All rights reserved.

The performance evaluation of pleated electret filters enhanced by electrostatic enhanced method

The filtration efficiency deterioration over operating time due to exposure to particles, organic solvents and other factors is an obvious defect of electret filter, especially during the coronavirus pandemic. Electrostatic enhanced method has been proposed as a promising way to improve the filtration efficiency and service time of electret filters without increasing the pressure drop. In this work, the effect of discharge electrode structure and operation mode of the electrostatic enhanced structure(EES) on the filtration efficiency of commercial pleated electret filters were studied firstly, then the EES was installed in a special designed prototype air purifier, two key indicators of air purifiers(clean air delivery rate (CADR) and cumulate clean mass (CCM)) were tested to evaluate the actual performance improvement of electret filters by the electrostatic enhanced method. It was found that the discharge electrode structure had significant influence on the filtration efficiency and multi-wire array electrode was more suitable for the discharge electrode to pleated filter to ground mesh structure used in this paper. The decayed electrostatic charges of pleated electret filter cannot be recharged again through the EES in actual operation condition. The filtration efficiency improvement of the test pleated electret filters was dominantly contributed by particle charging. The filter polarizing induced by the external electric field was helpful in increasing the filtration efficiency when the particles were charged while its effect on uncharged particles was almost negligible. Besides, the actual performance of the prototype air purifier indicated that the EES can alleviate the filtration efficiency deterioration of test electret filters and extend the service life of H11 and H13 filters by more than 3 and 1.5 times respectively according to the CCM test results. © 2023 IOP Publishing Ltd.

Using DTI tractography to guide tDCS interventions in a complex acquired brain Injury neurorehabilitation protocol - a case report

51-year-old man (C.P.) had a diffuse-axonal-injury after falling from a 5-meter height, followed by a 22-minute anoxia due to a cardiac arrest. In the ICU, he tested positive to COVID-19, and needed intubation. After coronavirus infection, C.P. presented Guillain-Barre syndrome. 2months after discharge, he was admitted to rehabilitation. DTI tractography for evaluation of the structural integrity of white matter tracts revealed: i) Lesions in the basal ganglia;ii) Sequelary lesions in the right frontal, cortical, subcortical, temporal, parieto-occipital and cerebellar hemispheres;iii) Asymmetry of the corticospinal tracts - less fibers on the left;iv) Poor definition of the fibers of the right arcuate fasciculus;v)Asymmetrical thinning of the cortico-ponto-cerebellar tracts, worse on the left, and more discreetly in the spinocerebellar tracts. Based on this, C.P. underwent 4 different 30-session tDCS protocols consisting of twice-daily 20min 2mA sessions (10min interval), 5days/week (120sessions total), combined with physiotherapy, cognitive, swallowing and speech therapy. Montages: Pr1 (anode: Cz - 5x10cm;cathode: 10th Thoracic Vertebra - 5x7cm);Pr2 (1 - anode:C3;cathode:Fp2 / 2 - anode: Cerebellum;cathode:Fp2);Pr3 (anode:F3;cathode:Fp2) and Pr4 (anode:Cp5;cathode:Fp2). Except for Pr1, electrode size for all protocols were 5x7cm. We used the Coma Recovery Scale (CRS-R) and Rancho Los Amigos Scale (RLAS) for clinical assessments at the baseline and after every 10 sessions until the end of the intervention. At the baseline, C.P. presented a minimal responsive state of consciousness (CRS-R: 3;RLAS: Level 1) and tolerated well the tDCS interventions. CRS-R scores gradually improved in various domains during the treatment. At the end, RLAS score was level 5 and CRS-R, 19. Our preliminary results suggest DTI tractography may be a potential biomarker to guide more personalized tDCS interventions for complex cases of patients with acquired brain injuries. A second DTI tractography will be made in the future for comparison purposes. Research Category and Technology and Methods Clinical Research: 9. Transcranial Direct Current Stimulation (tDCS) Keywords: Acquired Brain Injury, Traumatic Brain Injury, COVID-19, Guillain Barre SyndromeCopyright © 2023