Polyethylene Glycol-Mediated Directional Conjugation of Biological Molecules for Enhanced Immunoassays at the Point-of-Care.

Rapid and reliable point-of-care (POC) diagnostic tests can have a significant impact on global health. One of the most common approaches for developing POC systems is the use of target-specific biomolecules. However, the conjugation of biomolecules can result in decreased activity, which may compromise the analytical performance and accuracy of the developed systems. To overcome this challenge, we present a polymer-based cross-linking protocol for controlled and directed conjugation of biological molecules. Our protocol utilizes a bifunctional thiol-polyethylene glycol (PEG)-hydrazide polymer to enable site-directed conjugation of IgG antibodies to the surface of screen-printed metal electrodes. The metal surface of the electrodes is first modified with thiolated PEG molecules, leaving the hydrazide groups available to react with the aldehyde group in the Fc fragments of the oxidized IgG antibodies. Using anti-Klebsiella pneumoniae carbapenemase-2 (KPC-2) antibody as a model antibody used for antimicrobial resistance (AMR) testing, our results demonstrate a ~10-fold increase in antibody coupling compared with the standard N-hydroxysuccinimide (NHS)-based conjugation chemistry and effective capture (>94%) of the target KPC-2 enzyme antigen on the surface of modified electrodes. This straightforward and easy-to-perform strategy of site-directed antibody conjugation can be engineered for coupling other protein- and non-protein-based biological molecules commonly used in POC testing and development, thus enhancing the potential for improved diagnostic accuracy and performance.

Evaluation of Thyroid Lesions by Fine Needle Aspiration Cytology According to Bethesda System.

Aim To study cytology of various Thyroid lesions based on Bethesda system and to evaluate diagnostic accuracy of cytology by comparing it with histomorphological diagnosis whenever available. Materials and method In this study Fine needle aspiration cytology of 330 patients of clinically palpable thyroid were evaluated from June 2019 to December 2021 and categorised according to TBSRTC. 38 patients underwent surgical management in our hospital. Sensitivity, specificity, positive predictive value, negative predictive value reported under bethesda system were obtained by comparing the cytological and histopathological diagnosis where ever possible. Result The distribution of various categories from 330 evaluated thyroid nodules was as follows: 2.73% Non Diagnostic, 83.03% Benign, 0% Atypia of undetermined significance, 9.70% FN, 0.61% Suspicious for malignancy and 3.94% malignant. Sensitivity, specificity, positive predictive value, negative predictive value was 100, 60, 94.29 and 100% respectively. The diagnostic accuracy was calculated to be 94.73%. Conclusion There is a clearcut distinction between the two ends of the spectrum of non-neoplastic and neoplastic lesions of thyroid. Diagnostic accuracy of Bethesda system for reporting cytopathology for better clinical management is proven by the present study.

Are Short Duration Naps Better than Long Duration Naps for Mitigating Sleep Inertia? Brief Report of a Randomized Crossover Trial of Simulated Night Shift Work.

OBJECTIVE: We sought to test the effects of different duration naps on post-nap cognitive performance during simulated night shifts. METHODS: We used a randomized laboratory-based crossover trial design with simulated 12-hr night shifts and each participant completing three conditions of 72 hrs each (Clinicaltrials.gov; registration # NCT04469803). The three conditions tested included no-nap, a 30-min nap opportunity, and a 2-hr nap opportunity. Naps occurred at 02:00 hrs. Cognitive performance was assessed with the Brief 3-min Psychomotor Vigilance Test (PVT-B). Four PVT-B measures include: reaction time (RT in milliseconds (ms)), lapses (RT > 355 ms), false starts (reactions before stimulus or RT <100 ms), and speed (1,000/RT). The PVT-B was performed at the start of the simulated night shift (19:00), end of shift (07:00), pre-nap (02:00), and at 0 mins, 10 mins, 20 mins, and 30 mins following the 30-min and 2-hr nap conditions. Simultaneously, participants reported subjective ratings of fatigue and other constructs. RESULTS: Twenty-eight (15 female), mostly certified emergency medical technicians or paramedics, consented to participate. For all three conditions, looking within condition, PVT-B lapse performance at the end of the 12-hr simulated night shift (at 07:00) was poorer compared to shift start (p < 0.05). Performance on PVT-B speed, RT, and false starts were poorer at shift end than shift start for the no-nap and 30-min nap conditions (p < 0.05), but not for the 2-hr nap condition (p > 0.05). Compared to pre-nap measures, performance on the PVT-B assessed at 0 mins post-nap showed significant performance declines for lapses and speed for both the 30-min and 2-hr nap conditions (p < 0.05), but not at 10, 20, or 30 mins post-nap. After waking from the 2-hr on-shift nap opportunity (at 0 mins), participants rated sleepiness, difficulty with concentration, and alertness poorer than pre-nap (p < 0.05). Participants in the 30-min nap condition rated alertness poorer immediately after the nap (at 0 mins) compared to pre-nap (p < 0.05). CONCLUSIONS: While sleep inertia was detectable immediately following short 30-min and long 2-hr nap opportunities during simulated night shift work, deficits in cognitive performance and subjective ratings quickly dissipated and were not detectable at 10-30 mins post-nap.

Inflammasome regulation in driving COVID-19 severity in humans and immune tolerance in bats.

Coronaviruses (CoVs) are RNA viruses that cause human respiratory infections. Zoonotic transmission of the SARS-CoV-2 virus caused the recent COVID-19 pandemic, which led to over 2 million deaths worldwide. Elevated inflammatory responses and cytotoxicity in the lungs are associated with COVID-19 severity in SARS-CoV-2-infected individuals. Bats, which host pathogenic CoVs, operate dampened inflammatory responses and show tolerance to these viruses with mild clinical symptoms. Delineating the mechanisms governing these host-specific inflammatory responses is essential to understand host-virus interactions determining the outcome of pathogenic CoV infections. Here, we describe the essential role of inflammasome activation in determining COVID-19 severity in humans and innate immune tolerance in bats that host several pathogenic CoVs. We further discuss mechanisms leading to inflammasome activation in human SARS-CoV-2 infection and how bats are molecularly adapted to suppress these inflammasome responses. We also report an analysis of functionally important residues of inflammasome components that provide new clues of bat strategies to suppress inflammasome signaling and innate immune responses. As spillover of bat viruses may cause the emergence of new human disease outbreaks, the inflammasome regulation in bats and humans likely provides specific strategies to combat the pathogenic CoV infections.

Palatal lengthening by double opposing buccal flaps for surgical correction of velopharyngeal insufficiency in cleft patients.

AIM: To assess the efficacy of double opposing buccal flap in lengthening the soft palate for velopharyngeal insufficiency correction, and its potential complications in different age groups. CASE SERIES: From March 2016 to June 2019, 50 patients (24 children, 12 adolescents and 14 adults) underwent palatal lengthening using double opposing buccinator myomucosal flaps. Postoperative complications were assessed by two surgeons and the speech outcomes were evaluated by two speech-language pathologists after assessing changes in the hypernasality and intelligibility using a scoring approach. Following the procedure, mild-to-moderate surgical complications were seen, mostly among the adults. There was a significant improvement in hypernasality and intelligibility in all the groups. None of the patients showed hyponasal speech postoperatively. CONCLUSION: To conclude, the double opposing buccal flap technique is an effective and safe surgical treatment option for the management of velopharyngeal insufficiency in all age groups of patients.

Comparative evaluation of apically extruded debris during root canal instrumentation using two Ni-Ti single file rotary systems: An in vitro study.

BACKGROUND: Apical extrusion of debris during instrumentation is detrimental to the patient. AIM: The aim of this study was to evaluate the apical extrusion of debris during root canal instrumentation using two single file rotary Ni-Ti systems. MATERIALS AND METHODS: Thirty freshly extracted mandibular premolars with straight roots were sterilized and divided into two groups instrumented using: One Shape rotary Ni-Ti system with Endoflare orifice shaper (Group 1) and Neo-Niti rotary Ni-Ti system with C1 orifice shaper (Group 2). Preweighed Eppendorf tubes fitted for each tooth before instrumentation. During instrumentation, 1 mL of distilled water with a 30-gauge needle was used to irrigate after every instrument. Tips of the tooth were irrigated with 2 ml distilled water after removal from Eppendorf tubes. The total volume of irrigant in each group was the same 8 ml. All tubes were incubated at 68°C for 15 days and subsequently weighed. The difference between pre- and post-debris weights was calculated, and statistical analysis was performed using independent t-test and level of significance was set at 0.05. RESULTS: The difference between pre- and post-weights was significantly greater for the One Shape system. CONCLUSIONS: The Neolix Niti single file was associated with less extrusion compared to One Shape single file system.

Effect of different polishing systems on the surface roughness of nano-hybrid composites.

OBJECTIVE: The study aimed to investigate the influence of different polishing systems on the surface roughness of nano-hybrid composite resins. BACKGROUND: Different shapes of polishing systems are available according to the site of work. To minimize variability, a new system with single shape is developed that can be utilized in both anterior as well as posterior teeth. MATERIALS AND METHODS: Seventy composite discs were fabricated using Teflon well (10 mm × 3 mm). Two main group of nano-hybrid composite Group I - Filtek Z350 and Group II - Tetric N-Ceram were used (n = 35 for each group). Both groups were further divided into four subgroups. Subgroup a - OneGloss (n = 10), Subgroup b - PoGo (n = 10), Subgroup c - Sof-Lex spiral (n = 10), Subgroup d - Mylar strip (control, n = 5). Samples were polished according to the manufacturer's recommendations. Surface roughness test was performed using contact profilometer. The obtained data were analyzed using the one-way analysis of variance test. RESULT: Tetric N-Ceram produced smoother surfaces than Filtek Z350 (P < 0.05). Mylar strip and "PoGo" created equally smooth surfaces, while significantly rougher surfaces were obtained after applications of "Sof-Lex spiral" and "OneGloss" (P < 0.05). CONCLUSION: Polishing ability of Tetric N-Ceram is better than Filtek Z350 XT. "PoGo" seems to be a better polishing system than "OneGloss" and "Sof-Lex Spiral."

Sensing amyloid-ß aggregation using luminescent dipyridophenazine ruthenium(II) complexes.

The aggregation of amyloid-ß (Aß) peptides has been associated with the onset of Alzheimer's disease. Here, we report the use of a luminescent dipyridophenazine ruthenium(II) complex to monitor Aß fibrillization. This complex is not photoluminescent in aqueous solution nor in the presence of monomeric Aß, but it presents a strong photoluminescence in the presence of Aß fibril aggregates. One of the advantages of this metal complex is its large Stokes shift (180 nm). Furthermore, the long-lived photoluminescence lifetime of this ruthenium complex allows its use for the detection of fibrillar proteins in the presence of short-lived fluorescent backgrounds, using time-gating technology. We will present evidence of the advantages of dipyridophenazine ruthenium(II) complexes for monitoring protein fibrillization in highly fluorescent media.

Non-covalent ruthenium polypyridyl complexes-carbon nanotubes composites: an alternative for functional dissolution of carbon nanotubes in solution.

The dispersion of single-walled carbon nanotubes (SWCNTs) in the presence of water soluble polypyridyl complexes of the general formula [Ru(x)(bpy)(y)L](2+) (L = dppz, dppn, tpphz) is reported. These ligands have extended planar π systems, which aid in the solubilization of SWCNTs via π-π interactions.

A mutant selective anti-estrogen is a pure antagonist on EREs and AP-1 response elements.

Estrogen receptors (ERs) regulate gene transcription through classic estrogen response elements (EREs) as well as AP-1 responsive genes. The common SERMs Raloxifene, Tamoxifen, and ICI164384 function as ER antagonists on EREs but as ERbeta agonists/partial agonists on AP-1 responsive genes. While developing a mutant selective analog of Raloxifene, that is an antagonist of ERalpha(E353A), we discovered an antagonist of wild-type ERalpha and ERbeta that is also an antagonist of ERbeta/AP-1 response. The analog, DRL527, represses basal AP-1 gene expression and antagonizes Raloxifene stimulated AP-1 expression. Therefore DRL527 has a unique, previously unreported, ERE/AP-1 activity profile.

Endoscopic-assisted excision of esthesioneuroblastoma.

The purpose of this article is to report a case of esthesioneuroblastoma involving the bilateral paranasal sinuses, which was excised using an endoscopic-assisted transfacial approach. A patient presented with nasal swelling and left-sided nasal obstruction, epistaxis, and diplopia. Examination revealed broadening of the nasal dorsum with a fleshy pink mass in both nasal cavities. Computed tomographic scan showed a mass involving the nasal cavity and paranasal sinuses on both sides. The tumor was diagnosed as group C esthesioneuroblastoma. The mass was excised by bilateral medial maxillectomy and bilateral frontoethmoidectomy. Using a 0 degrees endoscope, the attachment of the tumor to the cribriform plate was identified and resected using a motordrill. On Waroff staining, Hispathology slides suggested esthesioneuroblastoma. The patient was asymptomatic for 1 year, following which he developed infection of the nasal cavity for which he had no form of treatment. He subsequently developed maggots in the nasal cavity after which he died. An endoscopic resection of the cribriform plate from the nasal cavity without a formal craniofacial resection can be safely performed with oncologic safety.