Evaluation of COVID-19 Antigen Fluorescence Immunoassay Test for Rapid Detection of SARS-CoV-2

Introduction

Tests detecting SARS-CoV-2-specific antigen have recently been developed, and many of them are now commercially available. However, the real-world performance of these assays is uncertain; therefore, their validation is important. In this study, we have evaluated the performance of STANDARD F COVID-19 antigen fluorescence immunoassay (FIA) kit.

Methods

Nasopharyngeal samples collected from patients were subjected to the test as per manufacturer's instructions. The performance of the kit was compared with the gold standard real-time polymerase chain reaction.

Results

A total of 354 patients were tested with STANDARD F COVID-19 antigen FIA test kit. The overall sensitivity, specificity, positive predictive value, and negative predictive value of this test were found to be 38%, 99%, 96.2%, and 72%, respectively, with a diagnostic accuracy of 75.7%.

Conclusion

STANDARD F COVID-19 antigen FIA showed high specificity and positive predictive value but low sensitivity and negative predictive value.

A duplicated coxI gene is associated with cytoplasmic male sterility in an alloplasmic Brassica juncea line derived from somatic hybridization with Diplotaxis catholica

A cytoplasmic male sterile (CMS) line of Brassica juncea was derived by repeated backcrossing of the somatic hybrid (Diplotaxis catholica + B. juncea) to B. juncea. The new CMS line is comparable to euplasmic lines for almost all characters, except for flowers which bear slender, needle-like anthers with aborted pollen. Detailed Southern analysis revealed two copies of coxI gene in the CMS line. One copy, coxI-1 is similar to the coxI gene of B. juncea, whereas the second copy, coxI-2 is present in a novel rearranged region. Northern analysis with eight mitochondrial gene probes showed altered transcript pattern only for the coxI gene. Two transcripts of 2.0 and 2.4 kb, respectively, were detected in the CMS line. The novel 2.4 kb transcript was present in floral bud tissue but absent in the leaf tissue. In plants where male sterility broke down under high temperature during the later part of the growing season, the 2.4 kb coxI transcript was absent, which suggested its association with the CMS. The two coxI genes from the CMS line showed two amino acid changes in the coding region. The novel coxI gene showed unique repeats in the 5' region suggesting recombination of mitochondrial genomes of the two species. The possible role of the duplicated coxI gene in causing male sterility is discussed.

Spermicidal activity of Indian seaweeds: an in vitro study

Contraceptive properties of seaweeds are still stands as lacuna; in this context, the screening of in vitro male contraceptive properties of crude ethanolic extract of Indian seaweeds against normal human sperm is carried out. In total, twelve seaweeds were screened for in vitro spermicidal activity. Among these twelve seaweeds, Halimeda gracilis showed 100% inhibition of human spermatozoa at 10 mg ml(-1) concentration in 20 s and its EC50 value was 2.05 mg ml(-1) in 20 s. Further, dose- and time-dependent spermicidal assay revealed that the sperm was completely immobilised for 20 s. Plasma membrane of sperm was damaged due to the exposure of H. gracilis extract. MTT assay with H. gracilis extract showed 88.5% of cytotoxic incidence. H. gracilis extract tested for cytotoxicity against Artemia salina recorded LC50 value of 34.8 μg ml(-1) . Phytochemical analysis of H. gracilis extract evidenced the presence of alkaloids, flavonoids, proteins and sugars. Results of this study clearly inferred that the synergistic effect of active principles reside within the H. gracilis extract had shown better contraceptive activity.

Characterization of ionic transport at the nanoscale

This paper reports on the development of a multi-layer microscale impedance measurement system with integrated working, counter, and reference electrodes that can be used to probe transport at the nanoscale. System fabrication and testing are carried out to demonstrate the feasibility of such a system for characterizing transport through nanocapillary array membranes (NCAMs). Results indicate that transport through NCAMs is a complex phenomenon, and impedance does not scale linearly with either pore diameter or ionic concentration. Use of a microscale construct for probing ionic transport at the nanoscale appears to be a promising path forward with further development.

Kidney Disease in Human Immunodeficiency Virus-seropositive Patients: Absence of Human Immunodeficiency Virus-associated Nephropathy was a Characteristic Feature

Human immunodeficiency virus (HIV) infection can cause a broad spectrum of renal diseases. However, there is paucity of Indian data on the patterns of renal lesions in HIV-seropositive patients. The aim of the present study was to delineate the spectrum of renal lesions in HIV/acquired immunodeficiency syndrome patients. In this prospective study, all HIV-positive patients of both genders aged >18 years were screened for renal disease. Patients with proteinuria of more than 1 g/24 h were subjected to renal biopsy. A total of 293 HIV-positive patients were screened; of these, 136 (46.4%) patients found to have renal involvement. Dipstick-positive proteinuria of 1+ or more was observed in 112 (38.2%) patients, and 16 (14.2%) patients had proteinuria of more than 1 g/24 h. Renal biopsy in 14 cases revealed glomerulonephritis (GN) in 12 (85.7%) (isolated GN in 4 [28.5%] and GN mixed with chronic TIN in 8 [57.1%]) patients. These include mesangioproliferative GN in 5 (35.7%), membranoproliferative GN in 2 (14.2%), focal segmental glomerulosclerosis in 2 (14.2%), diffuse proliferative GN in 2 (14.2%), and diabetic nephropathy in 1 (7.1%) patients. Chronic interstitial nephritis was noted in 10 (71.42%) (superimposed on GN in 8 [57.1%], isolated in 2 [14.2%]) patients. Granulomatous interstitial nephritis was seen in 3 (24.1%) cases. GN and chronic interstitial nephritis were noted in 85.7% and 71.42% of patients, respectively, mostly superimposed on each other. Mesangioproliferative GN was the most common glomerular lesion, but classical HIV-associated nephropathy was not observed.

Changing epidemiology of acute kidney injury in pregnancy: A journey of four decades from a developing country

The incidence of acute kidney injury in pregnancy (P-AKI) has markedly decreased over the last three decades in India, particularly due to decreased incidence of postabortion AKI. However, P-AKI still accounts for 3%-5% of cases of total AKI. Postabortion sepsis has decreased to between 0.9% and 1.5% in 2014 from 9.4% in 1980-1990 in the new millennium. Currently, in India, majority of P-AKI (70%-90%) occurs in the postpartum period and in late 3^rd trimester similar to the developed countries, but causes are different. We observed that preeclampsia/eclampsia is the most common cause of P-AKI in the late 3^rd trimester and postpartum period followed by puerperal sepsis and postpartum hemorrhage (PPH). Both puerperal sepsis and PPH are treatable and preventable etiologies of P-AKI. Timely and aggressive management of antepartum hemorrhage (APH/PPH) and puerperal sepsis are required to reduce the burden of P-AKI in developing countries. Specific-pregnancy disorders such as P-aHUS/thrombotic thrombocytopenic purpura, pregnancy-associated thrombotic microangiopathy, and acute fatty liver of pregnancy are the uncommon/rare causes of P-AKI in India and possibly also because of the lack of awareness toward diagnosis. Despite decreasing incidence of P-AKI, fetal mortality remained high and unchanged. However, maternal mortality has decreased to 5% from initial high mortality of 20%-25%. The incidence and severity of renal cortical necrosis have significantly decreased at our center.

Prospects for beyond the Standard Model physics searches at the Deep Underground Neutrino Experiment: DUNE Collaboration

The Deep Underground Neutrino Experiment (DUNE) will be a powerful tool for a variety of physics topics. The high-intensity proton beams provide a large neutrino flux, sampled by a near detector system consisting of a combination of capable precision detectors, and by the massive far detector system located deep underground. This configuration sets up DUNE as a machine for discovery, as it enables opportunities not only to perform precision neutrino measurements that may uncover deviations from the present three-flavor mixing paradigm, but also to discover new particles and unveil new interactions and symmetries beyond those predicted in the Standard Model (SM). Of the many potential beyond the Standard Model (BSM) topics DUNE will probe, this paper presents a selection of studies quantifying DUNE's sensitivities to sterile neutrino mixing, heavy neutral leptons, non-standard interactions, CPT symmetry violation, Lorentz invariance violation, neutrino trident production, dark matter from both beam induced and cosmogenic sources, baryon number violation, and other new physics topics that complement those at high-energy colliders and significantly extend the present reach.

Inhalational Ciclesonide found beneficial in prevention of fat embolism syndrome and improvement of hypoxia in isolated skeletal trauma victims

BACKGROUND

Many studies have established intravenous corticosteroid as an effective prophylactic therapy in fat embolism syndrome (FES). However, its use is limited among surgeons because of systemic side effects. Inhalational steroids have least systemic effects and are widely used for several chest conditions (i.e., asthma), but their effectiveness in FES has not been established.

QUESTION/PURPOSE

This study was sought to evaluate the (1) efficacy and (2) safety of inhalational Ciclesonide (CIC) in prevention of FES and treatment of hypoxemia in isolated skeletal trauma victims.

METHODS

A nonrandomized prospective control trial was designed in which all patients between 18 and 40 years with isolated skeletal injury who presented within 8 h of injury were allocated to either Trial group or control group. Trial group patients received 640 mcg of inhalational CIC with a metered-dose inhaler at the time of admission, and at 24 h. Control group patients did not receive any prophylactic therapy. Both groups were evaluated for development of FES (Gurd's criteria) and hypoxemia (PaO₂ <70 mmHg) for 72 h. The complications related to CIC administration were evaluated in trial group patients during their hospital stay.

RESULTS

Of 35 patients in each group, two patients in Trial group and nine patients in control group developed FES (P = 0.022). Eight patients in Trial group had hypoxemia at the time of admission, six of them improved and one additional patient developed hypoxemia after inhalational CIC administration. In control group, ten patients had hypoxia at the time of admission, only one of them improved and remaining nine patients had persistent hypoxemia even after 72 h. Additionally, three patients developed hypoxemia. A significant improvement in hypoxemia and a significant decrease in the incidence of FES were observed in Trial group (P < 0.05) compared to control group. None of the patients presented with any complications or adverse effects of steroid in Trial group.

CONCLUSION

Inhalational CIC is a safe and effective therapy for prevention of FES and also an effective drug for treatment of hypoxemia in orthopedic trauma victims.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Bimetallic PdAg nanoparticle arrays from monolayer films of diblock copolymer micelles

The self-assembly technique provides a highly efficient route to generate well-ordered structures on a nanometer scale. In this paper, well-ordered arrays of PdAg alloy nanoparticles on flat substrates with narrow distributions of particle size (6-7 nm) and interparticle spacing (about 60 nm) were synthesized by the block copolymer micelle approach. A home-made PS-b-P4VP diblock copolymer was prepared to obtain a micellar structure in toluene. Pd and Ag salts were then successfully loaded in the micellar core of the PS-b-P4VP copolymer. A self-assembled monolayer of the loaded micelles was obtained by dipping the flat substrate in the solution. At this stage, the core of the micelles was still loaded with the metal precursor rather than with a metal. Physical and chemical reducing methods were used to reduce the metal salts embedded in the P4VP core into PdAg nanoparticles. HRTEM and EDX indicated that Pd-rich PdAg alloy nanoparticles were synthesized by chemical or physical reduction; UV-visible spectroscopy observations confirmed that metallic PdAg nanoparticles were quickly formed after chemical reduction; XPS measurements revealed that the PdAg alloy nanoparticles were in a metallic state after a short time of exposure to O2 plasma and after hydrazine reduction.

Shoot regeneration in stem expiants and its amenability to Agrobacterium tumefaciens mediated gene transfer in Brassica carinata

Immature stem segments of seven different genotypes of Brassica carinata produced shoots with variable frequencies when cultured in MS medium with BAP and picloram at 0.2 mg/l each. Line 171, which produced shoots with 100% efficiency from both cut ends of the expiant, was selected for testing the amenability of this regeneration protocol for genetic transformation. A non-oncogenic Agrobacterium tumefaciens containing plasmid PCV 730, a binary vector carrying resistance genes for kanamycin and hygromycin, was used. A cocultivation period of 4 d with a bacterial concentration of approximately 2.5×10 cells/ml, followed by a recovery period of 2 d, produced transformed shoots that could be selected and rooted in the presence of kanamycin at 15 mg/l. Transformation was confirmed by neomycin phospho-transferase assay and Southern blot analysis. Seed analysis of transformed plants indicated that kanamycin resistance was inherited in the progeny.

Fibroblast-stimulating factor 1, a novel lymphokine produced in schistosomal egg granulomas, stimulates liver fat-storing cells in vitro

We report that the novel lymphokine fibroblast-stimulating factor 1, produced within hepatic schistosomal egg granulomas, stimulates liver fat-storing cells (FSC) in vitro to proliferate and express fibronectin genes. Because FSC are critical in hepatic fibrogenesis generally, we propose that in vivo stimulation of FSC by fibroblast-stimulating factor 1 may be an important step in schistosomal liver fibrosis.

Pulmonary nocardiosis: Report of two cases from a tertiary care hospital

Pulmonary nocardiosis is an uncommon bacterial infection that may lead to severe disease in immunocompromised patients. The disease is rare in immunocompetent patients. Reported cases are few, and the literature is limited because disease recognition is difficult. We present a case report of two patients of pulmonary nocardiosis, who had different clinicoradiological presentations and also responded differently to treatment. Given the rising incidence of cancer, organ transplantation, and use of parenteral steroids, Nocardia is likely to attain a higher place among the causes of pulmonary infections.