Subgenomic RNA identification in SARS-CoV-2 genomic sequencing data.

We have developed periscope, a tool for the detection and quantification of subgenomic RNA (sgRNA) in SARS-CoV-2 genomic sequence data. The translation of the SARS-CoV-2 RNA genome for most open reading frames (ORFs) occurs via RNA intermediates termed "subgenomic RNAs." sgRNAs are produced through discontinuous transcription, which relies on homology between transcription regulatory sequences (TRS-B) upstream of the ORF start codons and that of the TRS-L, which is located in the 5' UTR. TRS-L is immediately preceded by a leader sequence. This leader sequence is therefore found at the 5' end of all sgRNA. We applied periscope to 1155 SARS-CoV-2 genomes from Sheffield, United Kingdom, and validated our findings using orthogonal data sets and in vitro cell systems. By using a simple local alignment to detect reads that contain the leader sequence, we were able to identify and quantify reads arising from canonical and noncanonical sgRNA. We were able to detect all canonical sgRNAs at the expected abundances, with the exception of ORF10. A number of recurrent noncanonical sgRNAs are detected. We show that the results are reproducible using technical replicates and determine the optimum number of reads for sgRNA analysis. In VeroE6 ACE2+/- cell lines, periscope can detect the changes in the kinetics of sgRNA in orthogonal sequencing data sets. Finally, variants found in genomic RNA are transmitted to sgRNAs with high fidelity in most cases. This tool can be applied to all sequenced COVID-19 samples worldwide to provide comprehensive analysis of SARS-CoV-2 sgRNA.

Kisspeptin stimulates oestradiol biosynthesis by upregulating steroidogenic transcripts and proliferation markers in the bubaline granulosa cells in vitro.

Kisspeptin (Kp), an upstream regulator of GnRH release, is essential for the development and function of reproductive axis. Previously, we demonstrated the localization of Kp and its receptor (Kiss1r) in the active follicle in the bubaline ovary. Present study aimed to determine the effect of Kp on granulosa cell (GCs) functions, especially oestradiol (E2 ) and progesterone (P4 ) production, and differential expression of genes regulating the proliferation, apoptosis and steroidogenesis in the buffalo. The ovaries with 6-10 mm size follicles obtained from the cyclic buffaloes after slaughtering were used for isolation of GCs for in vitro study. The primary GCs culture was treated with Kp (0, 10, 50 and 100 nM) and incubated for 48 h. Production of E2 and P4 was estimated in the culture supernatant by ELISA. The expression of gonadotropin receptors (FSHR and LHR), steroidogenic genes (STAR, 3ß-HSD, CYP19A1), proliferation marker (PCNA), apoptotic factors (CASP3 and BCL2) and Kp signalling molecule (extracellular signal-regulated kinase 1/2, ERK1/2 and p-ERK1/2) was studied in the GCs by qPCR. Significant E2 production was found in the Kp 50 and 100 nM groups (p < .05), whereas P4 production was reduced in Kp 100 nM group (p < .05). There was concomitant upregulation of FSHR, ERK1/2, STAR and CYP19A1 in the Kp 100 nM treated GCs. In addition, Kp at 100 nM stimulated the proliferation of GCs by upregulating the expression of BCL2 (5.0 fold) and PCNA (94.9 fold). Further, high immunoreactivity of p-ERK1/2 was observed in the Kp-treated GCs. It was concluded that Kp at 100 nM concentration stimulated E2 production by upregulating the steroidogenic pathway through ERK1/2, STAR and CYP19A1 and modulating PCNA and BCL2 expressions in the GCs. Further experiments are warranted using Kp antagonist in different combinations to establish the signalling pathway in Kp-mediated steroidogenesis in the GCs for developing strategies to control ovarian functions.

Diagnosis of SARS-CoV-2 Infection with LamPORE, a High-Throughput Platform Combining Loop-Mediated Isothermal Amplification and Nanopore Sequencing.

LamPORE is a novel diagnostic platform for the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA combining loop-mediated isothermal amplification with nanopore sequencing, which could potentially be used to analyze thousands of samples per day on a single instrument. We evaluated the performance of LamPORE against reverse transcriptase PCR (RT-PCR) using RNA extracted from spiked respiratory samples and stored nose and throat swabs collected at two UK hospitals. The limit of detection of LamPORE was 10 genome copies/µl of extracted RNA, which is above the limit achievable by RT-PCR, but was not associated with a significant reduction of sensitivity in clinical samples. Positive clinical specimens came mostly from patients with acute symptomatic infection, and among them, LamPORE had a diagnostic sensitivity of 99.1% (226/228; 95% confidence interval [CI], 96.9% to 99.9%). Among negative clinical specimens, including 153 with other respiratory pathogens detected, LamPORE had a diagnostic specificity of 99.6% (278/279; 98.0% to 100.0%). Overall, 1.4% (7/514; 0.5% to 2.9%) of samples produced an indeterminate result on first testing, and repeat LamPORE testing on the same RNA extract had a reproducibility of 96.8% (478/494; 94.8% to 98.1%). LamPORE has a similar performance as RT-PCR for the diagnosis of SARS-CoV-2 infection in symptomatic patients and offers a promising approach to high-throughput testing.

Clinical features and outcome of COVID-19 positive children from a tertiary healthcare hospital in Karachi.

: As the coronavirus disease 2019 (COVID-19) pandemic continues to evolve, differences in epidemiological and clinical features among pediatrics have been noticed across different countries. We describe the spectrum of COVID-19 in pediatric patients treated in tertiary health care. We conducted a retrospective chart review of pediatric patients admitted to Indus Hospital & Health care network, Korangi campus, Karachi; from April 1st, 2020 to July 31st, 2020. A total of 141 COVID-19 cases were reported, males were 81 (57%) and the median age was 8 (0.3-17) years. Moderate and severe infections were noted in 36(26%), and 17(12%) children respectively. Fever (50%) was the most common clinical feature. The SF ratio less than 264 was significantly associated with severe disease (p < .05). Lab investigations that differed significantly across disease severity groups included IL-6 levels (p < .01) and Prothrombin time (p < .05). Majority of children were advised home isolation 89 (63%), 29 (20.5%) were admitted while mortality was observed in 10 (7%) children. No significant difference was observed between children with and without malignancy. Pre-existing comorbidities are significantly associated with COVID-19 infections among children. Reduced SF ratio, elevated Prothrombin time, and interleukin-6 levels are associated with greater disease severity.

Roll-out of SARS-CoV-2 testing for healthcare workers at a large NHS Foundation Trust in the United Kingdom, March 2020.

Healthcare workers (HCW) are potentially at increased risk of infection with coronavirus disease (COVID-19) and may transmit severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to vulnerable patients. We present results from staff testing at Sheffield Teaching Hospitals NHS Foundation Trust, United Kingdom. Between 16 and 29 March 2020, 1,533 symptomatic HCW were tested, of whom 282 (18%) were positive for SARS-CoV-2. Testing HCW is a crucial strategy to optimise staffing levels during this outbreak.

Degenerative Mitral Stenosis: Unmet Need for Percutaneous Interventions.

Degenerative mitral stenosis (DMS) is an important cause of mitral stenosis, developing secondary to severe mitral annular calcification. With the increase in life expectancy and improved access to health care, more patients with DMS are likely to be encountered in developed nations. These patients are generally elderly with multiple comorbidities and often are high-risk candidates for surgery. The mainstay of therapy in DMS patients is medical management with heart rate control and diuretic therapy. Surgical intervention might be delayed until symptoms are severely limiting and cannot be managed by medical therapy. Mitral valve surgery is also challenging in these patients because of the presence of extensive calcification. Hence, there is a need to develop an alternative percutaneous treatment approach for patients with DMS who are otherwise inoperable or at high risk for surgery. In this review, we summarize the available data on the epidemiology of DMS and diagnostic considerations and current treatment strategies for these patients.

Relationship of mitral valve annulus plane and circumflex-right coronary artery plane: Implications for Transcatheter Mitral Valve Implantation.

AIM: Transcatheter mitral valve implantation (TMVI) is a novel technology for patients with severe mitral valve disease but at high surgical risk. Imaging guidance during the procedure is critical for successful device deployment. Identification of the mitral annular plane (MAP) with fluoroscopy during the procedure is limited by lack of clearly defined landmarks. We hypothesized that a plane defined by left circumflex-right coronary arteries (LCX-RCA) would have a consistent relationship to MAP. METHODS AND RESULTS: We studied 25 patients with gated cardiac computed tomography. We identified the MAP and the LCX-RCA plane in mid systole and diastole. The distance between the two planes in prespecified four points (anterior, posterior, medial, and lateral) in the apical 2 and 3-chamber views. Alignment of the planes was described by cranial/caudal angulation for both planes in RAO 30° and LAO 90° (lateral) angulation. Mean age was 81 ± 9 years, 56% of patients had ≥2+ mitral regurgitation. In mid systole, the distances between the LCX-RCA plane and the MAP in the four points were < 5 mm in 92% of patients. In mid diastole, distances were < 5 mm in 100% of patients. In mid systole, the correlation between the caudal/cranial orientations of the 2 planes was 0.85 and 0.80 in the LAO 90° and RAO 30°, respectively (P = <0.001). In mid diastole, this was 0.92 and 0.92 in the LAO 90° and RAO 30°, respectively (P = <0.001). CONCLUSION: LCX-RCA plane has a close and consistent relationship to the MAP and can be useful to guide TMVI. Accurate imaging of mitral valve annular plane during TMVI procedure is challenging. MAP guided by fluoroscopy might be crucial to guide successful prosthesis deployment. A plane defined by the left circumflex- right coronary arteries in the atrioventricular grove has a consistent relationship with MAP; this can be used aided by pre-procedural MDCT to guide TMVI procedure. © 2016 Wiley Periodicals, Inc.

Clinical Spectrum, Treatment and Outcome of Children with Autoimmune Encephalitis.

OBJECTIVE: To assess the clinical spectrum, treatment, and outcome of children with autoimmune encephalitis (AE). STUDY DESIGN: Descriptive study. Place and Duration of the Study: Department of Paediatrics, The Aga Khan University Hospital, Karachi, Pakistan, from January 2017 to December 2021. METHODOLOGY: Medical records of children with a diagnosis of AE were reviewed for clinical features, treatment details, and outcomes. Outcome was defined as good (0-2) or poor (3-6) based on a modified Rankin Scale (mRS) score at 3-month follow-up. Descriptive statistics were reported and logistic regression was used to assess the prognostic factors associated with outcome. RESULTS: Thirty-three patients were identified with AE. Thirteen (39.3%) were antibody positive. Anti-N-methyl-D-aspartate receptor (NMDAR) antibody was seen in 92% of positive cases. Behavioural abnormalities (87.8%), seizures (81.8%), movement disorders (66.6%), psychiatric symptoms (63.6%), and mutism (33.3%) were the prominent symptoms. Thirty (91%) patients received first-line immunotherapy. Good outcome was seen in 14 (48.2%) patients. Univariable analysis showed that the odds of having poor outcome were 2.5 (95% confidence interval [CI] 0.37-16.88, p=0.34) in patients with chorea. In addition, an elevated cerebrospinal fluid (CSF) protein had an odds ratio (OR) of 8.6 (CI 0.88-84.83, p=0.064) and positive CSF antibodies had an OR of 3.7 (CI 0.79-17.72, p=0.095) for a poor outcome. Mortality was seen in 4 (12.1%) patients. CONCLUSION: A very low threshold is needed for the diagnosis of AE in children presenting with behavioural symptoms and chorea. Although the odds for poor prognosis were higher in patients with chorea, elevated CSF protein and positive CSF antibodies, the p-value did not come out significant. KEY WORDS: Autoimmune encephalitis, Antibodies, NMDAR, Immunotherapies, mRS score, Outcome.

Assessment of occupational musculoskeletal disorders (MSDs) among heavy vehicle drivers.

BACKGROUND: Professional driving requires long hours of work, uncomfortable seats, negotiating rough terrain and highways, and possibly minor repairs and other auxiliary transportation duties. Heavy vehicle drivers driving vehicles such as trucks, bulldozers, etc. due to such working structures are more prone to various musculoskeletal disorders (MSDs) and pain, which is of great concern. OBJECTIVES: In the present study, it is planned to investigate possible ergonomic risk factors such as age, weight, driving exposure, seat suspension systems, lifting heavy weights causing MSDs in drivers of various heavy vehicles. The results of the study are expected to help drivers reduce the risk of MSDs. METHODS: For the present study, the Nordic questionnaire on musculoskeletal disorders was modified and standardized and was administered to the 48 heavy vehicle drivers randomly selected to collect the data. RESULTS: The analysis divulged that over the past 12 months, lower back pain (LBP) emerged as the most dominant pain experienced by 56% of drivers, followed by knee pain (KP) (43%) and neck pain (NP) (39%) respectively. The prevalence of shoulder pain (SP) was observed to be much lower than in previous literature. The logistic regression model further revealed that increasing age, poor suspension system and poor body posture were significantly associated with lower back pain. Additionally, a poor suspension system and lifting heavy weights had significant effect on the drivers' knee pain. CONCLUSION: The results demonstrated the evident necessity for ergonomic consideration in vehicle designing and ergonomic training for heavy vehicle drivers.

Inner Ear Function Evaluation in Mobile Phone Users: A Cross-Sectional Study From a Tertiary Care Centre in North India.

Background India has approximately 1.02 billion mobile phone users. The electromagnetic radiations emitted by telecommunication systems are absorbed by the recipient's body, leading to changes in brain electrical activity, sensations of warmth or burning around the ear, and alterations in the blood-brain barrier. The inner ear, being the closest organ during mobile phone use, directly receives these electromagnetic radiations. This study aims to assess the inner ear function among mobile phone users, investigate the impact of mobile phones on the hearing thresholds of volunteers through pure-tone audiometry (PTA), and delve into the same using otoacoustic emissions (OAE). Methodology A cross-sectional study was conducted at a single center in North India from September 2020 to March 2021. The sample size of around 100 was determined using G Power software (G Power, Aichach, Germany), including volunteers aged 18-25, using mobile phones for over a year with normal hearing. Exclusions involved various ear-related histories or chronic systemic illnesses. Dominant and non-dominant ear groups were formed based on mobile phone usage. The study involved comprehensive ENT examinations, pure-tone audiometry, and otoacoustic emissions. We performed statistical analyses using SPSS version 22.0 (IBM Corp., Armonk, NY), which presented descriptive statistics and employed tests for group comparisons. Results Most participants were in the 21-23 age group (56%), with a mean age of 22.16 ± 1.77 years. There were 45 males and 55 females. The mean mobile phone usage was 6.6 ± 1.98 years, with varying daily durations. The dominant ear for mobile phone usage was predominantly the right ear (75 participants). Pure-tone audiometry results showed no statistically significant differences between dominant and non-dominant ears. Among the 24 participants with absent OAE, no significant association was found with mobile phone usage duration. Notably, the highest incidence of absent OAE occurred in the 120-180-minute usage category. Conclusion Mobile phones have seamlessly integrated into the lives of individuals, witnessing an exponential increase in users over time. The inner ear, situated in proximity to mobile phone usage, is of particular concern. While there is existing evidence indicating potential adverse effects of mobile phones on the inner ear, further long-term studies involving larger populations are essential to comprehensively evaluating the impact on inner ear function among mobile phone users.

Diagnostic dilemmas and challenges in the management of myasthenia in infants and toddlers: A case report.

Myasthenia in the infancy and toddler age group is rare and often presents a challenge to treating pediatric neurologists. Our report addresses the challenges encountered when distinguishing myasthenia in infants and toddlers from similar illnesses, as well as the differentiation between congenital myasthenia, transient myasthenia, and autoimmune myasthenia. We present four cases of myasthenia between the ages of 10 and 30 months. The diagnosis and management of these cases were challenging due to the variability in clinical presentation. Four cases of myasthenia were diagnosed, with three having autoimmune myasthenia and one having congenital myasthenic syndrome. One patient initially tested negative for acetylcholine receptor antibodies, but later tested positive after 4 months and had a rare facial diplegia finding. The patient with congenital myasthenic syndrome had a novel genetic mutation, DPAGT1 homozygous variants, and also had false positive acetylcholine receptor antibodies. These cases highlight the importance of genetic testing for all infants and toddlers suspected of having myasthenia.

Effectiveness of levofloxacin in the induction of chemotherapy in high-risk acute lymphoblastic leukaemia in children in a developing country.

Background: Infections significantly predominate during induction chemotherapy for acute lymphoblastic leukaemia (ALL) in children. Antibacterial prophylaxis is one strategy that lowers the risk of these infections. This study evaluates the role of levofloxacin prophylaxis on the frequency of infections, febrile neutropenia (FN) and outcomes associated with it along with the development of drug-resistance. Subject and methods: This was a single-centre cohort study in which the data were collected from electronic health records between two cohorts of high-risk ALL patients in the induction phase: the first one before the initiation of levofloxacin prophylaxis and the second was after the implementation of levofloxacin prophylaxis. The variables were compared between both the groups and odds ratios were calculated for clinical outcomes. Results: Out of 227 patients, 115 were given levofloxacin prophylaxis and 112 were in the no prophylaxis group. Both cohorts were similar in demographic factors, treatment regimen and supportive care services. There was a significant difference in total in-patient admissions along with FN admissions (p = 0.026). Microbiologically documented infections and infection-related critical interventions were significantly higher in the no prophylaxis group (p < 0.05). Odds ratios with a 95% confidence interval were applied to both groups for clinical outcomes in patients with and without FN which also illustrated similar results. Overall mortality and drug resistance patterns were similar among both groups. Conclusion: This study emphasised that levofloxacin is effective in reducing inpatient admissions with FN and its complications but did not affect the drug-resistance pattern. Long-term monitoring for antibiotic resistance is mandatory.

HTLV seroprevalence in people using HIV pre-exposure prophylaxis in England.

OBJECTIVES: HTLV-1 is predominantly a sexually-transmitted infection but testing is not mentioned in HIV-PrEP guidelines. We ascertained HTLV-1/HTLV-2 seroprevalence amongst HIV-PrEP users in England. METHODS: An unlinked anonymous seroprevalence study. RESULTS: Amongst 2015 HIV-PrEP users, 95% were men, 76% of white ethnicity and 83% had been born in Europe. There were no HTLV-1/HTLV-2 seropositive cases (95% confidence interval 0% - 0.18%). CONCLUSIONS: There were no HTLV positive cases, likely reflecting the demographic of mostly white and European-born individuals. Similar studies are needed worldwide to inform public health recommendations for HIV-PrEP using populations, particularly in HTLV-endemic settings.

Enhancement of Electrochemical Stability Window and Electrical Properties of CNT-Based PVA-PEG Polymer Blend Composites.

New polymer blend composite electrolytes (PBCEs) were prepared by the solution casting technique using poly(vinyl alcohol) (PVA)-polyethylene glycol (PEG), sodium nitrate (NaNO3) as a doping salt and multiwalled carbon nanotubes (MWCNTs) as fillers. The X-ray diffraction pattern confirms the structural properties of the polymer blend composite films. FTIR investigations were carried out to understand the chemical properties and their band assignments. The ionic conductivity of the 10 wt % MWCNTs incorporated PVA-PEG polymer blend was measured as 4.32 × 10-6 S cm-1 at 20 °C and increased to 2.253 × 10-4 S/cm at 100 °C. The dependence of its conductivity on temperature suggests Arrhenius behavior. The equivalent circuit models that represent the R s(Q1(R1(Q2(R2(CR3))))) were used to interpret EIS data. The dielectric behavior of the samples was investigated by utilizing their AC conductance spectra, dielectric permittivity, dielectric constant (εi and εr), electric modulus (Mi and Mr), and loss tangent tan δ. The dielectric permittivity of the samples increases due to electrode polarization effects in low frequency region. The loss tangent's maxima shift with increasing temperature; hence, the peak height rises in the high frequency region. MWCNTs-based polymer blend composite electrolytes show an enhanced electrochemical stability window (4.0 V), better transference number (0.968), and improved ionic conductivity for use in energy storage device applications.

An Unusual Etiology: Subarachnoid Hemorrhage Resulting in Transient Apical Ballooning Syndrome.

Intracranial bleeds, such as subarachnoid hemorrhage, carry high morbidity and mortality rates. Often intracranial hemorrhages result in debilitating residual neurological symptoms but can be so extensive that cardiac complications can also be seen. We present a rare case of a patient who was found to have a subarachnoid hemorrhage that incited the development of Takotsubo cardiomyopathy, which subsequently progressed to an acute myocardial infarction. The aim of this case report is to explore the underlying pathophysiology of how cerebral hemorrhage can result in apical ballooning of the left ventricle through various mechanisms including sympathetic-induced surge in catecholamines and neurogenic damage to the myocardium. We also intend to highlight the importance for clinicians to consider brain bleeds in the differential diagnosis when a patient presents with an acute myocardial infarction as treatment with heparin is generally contraindicated.

Characterising within-hospitalSARS-CoV-2 transmission events using epidemiological and viral genomic data across two pandemic waves.

Hospital outbreaks of COVID19 result in considerable mortality and disruption to healthcare services and yet little is known about transmission within this setting. We characterise within hospital transmission by combining viral genomic and epidemiological data using Bayesian modelling amongst 2181 patients and healthcare workers from a large UK NHS Trust. Transmission events were compared between Wave 1 (1st March to 25th J'uly 2020) and Wave 2 (30th November 2020 to 24th January 2021). We show that staff-to-staff transmissions reduced from 31.6% to 12.9% of all infections. Patient-to-patient transmissions increased from 27.1% to 52.1%. 40%-50% of hospital-onset patient cases resulted in onward transmission compared to 4% of community-acquired cases. Control measures introduced during the pandemic likely reduced transmissions between healthcare workers but were insufficient to prevent increasing numbers of patient-to-patient transmissions. As hospital-acquired cases drive most onward transmission, earlier identification of nosocomial cases will be required to break hospital transmission chains.

Altered subgenomic RNA abundance provides unique insight into SARS-CoV-2 B.1.1.7/Alpha variant infections.

B.1.1.7 lineage SARS-CoV-2 is more transmissible, leads to greater clinical severity, and results in modest reductions in antibody neutralization. Subgenomic RNA (sgRNA) is produced by discontinuous transcription of the SARS-CoV-2 genome. Applying our tool (periscope) to ARTIC Network Oxford Nanopore Technologies genomic sequencing data from 4400 SARS-CoV-2 positive clinical samples, we show that normalised sgRNA is significantly increased in B.1.1.7 (alpha) infections (n = 879). This increase is seen over the previous dominant lineage in the UK, B.1.177 (n = 943), which is independent of genomic reads, E cycle threshold and days since symptom onset at sampling. A noncanonical sgRNA which could represent ORF9b is found in 98.4% of B.1.1.7 SARS-CoV-2 infections compared with only 13.8% of other lineages, with a 16-fold increase in median sgRNA abundance. We demonstrate that ORF9b protein levels are increased 6-fold in B.1.1.7 compared to a B lineage virus in vitro. We hypothesise that increased ORF9b in B.1.1.7 is a direct consequence of a triple nucleotide mutation in nucleocapsid (28280:GAT > CAT, D3L) creating a transcription regulatory-like sequence complementary to a region 3' of the genomic leader. These findings provide a unique insight into the biology of B.1.1.7 and support monitoring of sgRNA profiles to evaluate emerging potential variants of concern.

Prediction of biological protein-protein interactions using atom-type and amino acid properties.

Identification and analysis of types of biological protein-protein interactions and their interfaces to predict obligate and non-obligate complexes is a problem that has drawn the attention of the research community in the past few years. In this paper, we propose a prediction approach to predict these two types of complexes. We use desolvation energies - amino acid and atom type - of the residues present in the interface. The prediction is performed via two state-of-the-art classification techniques, namely linear dimensionality reduction (LDR) and support vector machines (SVM). The results on a newly compiled data set, namely BPPI, which is a joint and modified version of two well-known data sets consisting of 213 obligate and 303 non-obligate complexes, show that the best prediction is achieved with SVM (76.94% accuracy) when using desolvation energies of atom-type features. Also, the proposed approach outperforms the previous solvent accessible area-based approaches using SVM (75% accuracy) and LDR (73.06% accuracy). Moreover, a visual analysis of desolvation energies in obligate and non-obligate complexes shows that a few atom-type pairs are good descriptors for these types of complexes.

Investigations on Structural, Optical Properties, Electrical Properties and Electrochemical Stability Window of the Reduced Graphene Oxides Incorporated Blend Polymer Nanocomposite Films.

The incorporation of reduced Graphene oxides (rGO) as a nanofiller in the blend polymer nanocomposite (BPNC) based on Polyvinylpyrrolidone (PVP)-Polyvinylalcohol (PVA) and sodium bicarbonate (NaHCO3) are presented. The blend polymer electrolytes films are prepared by the standard solution cast technique, and it is characterized to investigate the structural, morphological, thermal, optical and electrochemical property. The X-ray diffraction confirms the formation of polymer nanocomposite and is agreed with FESEM analysis. The FTIR confirms the presence of various interactions between the polymer, salt and rGO, and indicates the composite formation. The DSC examines the thermal property of the blend polymer nanocomposite electrolytes system. The bandgap energy has been obtained from the UV-spectroscopy and examines the direct and indirect gap, both offer the decreases bandgap with the addition of a higher concentration of rGO as nanofillers. The highest value of ionic conductivity of the film is obtained ~1.39×10-6 S cm-1 at 15 wt.% of rGO content in polymer blend nanocomposite (BPNC) films. For these BPNC films, the electrochemical stability window (ESW) is ~4.0 V at 25 wt.% of rGO content and ionic transport number (tion) is ~0.98, for 10 wt.% of rGO content at the room temperature. These highly stable blend polymer nanocomposite electrolyte films offer the excellent properties for utilized as a separator for solid-state devices e.g., battery, supercapacitors, electrochromic display devices and other electrochemical energy storage/ conversion devices respectively.