Performance assessment of seven SARS-CoV-2 IgG enzyme-linked immunosorbent assays.

The pandemic of COVID-19 has caused enormous fatalities worldwide. Serological assays are important for detection of asymptomatic or mild cases of COVID-19, and sero-prevalence and vaccine efficacy studies. Here, we evaluated and compared the performance of seven commercially available enzyme-linked immunosorbent assay (ELISA)s for detection of anti-severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) immunoglobulin G (IgG). The ELISAs were evaluated with a characterized panel of 100 serum samples from qRT-PCR confirmed COVID-19 patients, collected 14 days post onset disease, 100 SARS-CoV-2 negative samples and compared the results with that of neutralization assay. Results were analysed by creating the receiver operating characteristic curve of all the assays in reference to the neutralization assay. All kits, were found to be suitable for detection of IgG against SARS-CoV-2 with high accuracy. The DiaPro COVID-19 IgG ELISA showed the highest sensitivity (98%) among the kits. The assays demonstrated high sensitivity and specificity in detecting the IgG antibodies against SARS-CoV-2. However, the presence of IgG antibodies does not always correspond to neutralizing antibodies. Due to their good accuracy indices, these assays can also aid in tracing mild infections, in cohort studies and in pre-vaccine evaluations.

Electron-Transparent Thermoelectric Coolers Demonstrated with Nanoparticle and Condensation Thermometry.

More efficient thermoelectric devices would revolutionize refrigeration and energy production, and low-dimensional thermoelectric materials are predicted to be more efficient than their bulk counterparts. But nanoscale thermoelectric devices generate thermal gradients on length scales that are too small to resolve with traditional thermometry methods. Here we fabricate, using single-crystal bismuth telluride (Bi2Te3) and antimony/bismuth telluride (Sb2-xBixTe3) flakes exfoliated from commercially available bulk materials, functional thermoelectric coolers (TECs) that are only 100 nm thick. These devices are the smallest TECs ever demonstrated by a factor of 104. After depositing indium nanoparticles to serve as nanothermometers, we measure the heating and cooling produced by the devices with plasmon energy expansion thermometry (PEET), a high-spatial-resolution, transmission electron microscopy (TEM)-based thermometry technique, demonstrating a ΔT = -21 ± 4 K from room temperature. We also establish proof-of-concept for condensation thermometry, a quantitative temperature-change mapping technique with a spatial precision of ≲300 nm.

Sinonasal adenoid cystic carcinoma-role of on-site FNAC: a case report.

BACKGROUND: Adenoid cystic carcinoma (ACC), a rare tumor of epithelial cell origin, commonly arises from the major salivary glands. Uncommonly it may be found outside the salivary glands and it's especially rare in the nasal cavity. CASE PRESENTATION: A 71-year female had complaints of swelling at the base of nose, Fine needle aspiration (FNA) from the swelling revealed features of adenoid cystic carcinoma; cell block & IHC for CD-117 was positive. CONCLUSIONS: Sino-nasal ACC (SNACC) continues to pose diagnostic and therapeutic challenges to clinicians. Due to its rarity & vague presentation, early diagnosis requires a high index of suspicion. FNA can be used as an invaluable diagnostic tool in the evaluation of these lesions. Since it's incidence in sinonasal region is rare; our attempt to report this case will heighten the physician's awareness of this disease, helping further treatment.

Disseminated histoplasmosis in an immunocompetent patient - utility of skin scrape cytology in diagnosis: a case report.

BACKGROUND: Histoplasma capsulatum is a dimorphic fungus predominately found in soils enriched with bird and bat excreta. Although several cases of histoplasmosis have been reported in India, diagnosis using cytology has been done in very few cases. CASE PRESENTATION: We report here a case of disseminated histoplasmosis in a 46-year-old Indian man. CONCLUSION: Skin scrape cytology is a simple, safe, and rapid technique to establish the initial diagnosis, thus promoting early treatment and favorable outcome, in cutaneous fungal infections.

Incidental detection of two adult gravid filarial worms in breast: a case report.

BACKGROUND: Microfilaria is a major public health problem in tropical and subtropical countries and is an endemic problem in India. Wuchereria bancrofti is the commonest filarial infection. In some lesions, microfilariae and adult filarial worm have been incidentally detected in fine-needle aspirates. CASE PRESENTATION: A 35 year old hindu female presented with lump in upper outer quadrant of left breast. Fine needle aspiration revealed two adult gravid female filarial worms. CONCLUSION: To our knowledge this is the first ever case report to demonstrate two live gravid female and embryoid forms in wet mount preparation.

Loose cell clusters with vascular coats: Zellballen pattern of paraganglioma on cytology.

Paragangliomas are uncommon tumors arising in paraganglion tissue, which is well represented in the head and neck. A correct pre-operative cytological diagnosis helps in planning early and optimal surgery. Cytologic features in carotid body tumor and extra adrenal paragangliomas have been well described and documented. In addition to the acinar and discrete arrangement of cells, smears also showed a few large loose clusters of cells enveloped by thin vascular channels-the so-called zellballen pattern, a diagnostic feature on histopathology. Zellballen pattern of paraganglioma on cytology is not a common finding and hence is being reported.