UV Spectrophotometric Method for Quantification of Rivastigmine Tartrate in Simulated Nasal Fluid: Development and Validation

Background: Rivastigmine Tartrate belongs to the class of cholinesterase inhibitors in Anti-alzheimer’s disease with optimum therapeutic efficacy. Till now no validated method of its quantification has been reported in simulated nasal fluid. Objective: The current research investigation aims to develop a rapid, simple, and reliable UV spectrophotometric method for the quantitative determination of the pure form of Rivastigmine Tartrate in SNF. Method: A suitable method was developed by using double beam UV spectrophotometer and selection of a suitable solvent system for estimation of Rivastigmine Tartrate at absorbance maxima 263nm in SNF. The method was validated for various parameters like including accuracy, linearity and precision as per the International Conference on Harmonization guidelines. Results: The method developed by selecting simulated nasal fluid as the solvent system satisfied the optimum condition of the good quality peak at the selected wavelength. The results proposed the developed method for Rivastigmine Tartrate quantification in the simulated nasal fluid to be linear in the working concentration range of 5-60 µg/ml with a co-relation coefficient of 0.998. The % accuracy was found to be 99.8 -100.57. The % RSD values were < 2 while LOD & LOQ values were detected to be 0.316 and 1.053 respectively. Conclusion: The stated method was analyzed to be rapid, accurate, reliable, and precise. Further, it can be used in checking the quality control parameters of the Rivastigmine Tartrate in routine analysis.

Investigation of Three Newly Identified Equine Parvoviruses in Blood and Nasal Fluid Samples of Clinically Healthy Horses and Horses with Acute Onset of Respiratory Disease

Three newly identified equine parvoviruses (equine parvovirus hepatitis (EqPV-H), equine parvovirus CSF (EqPV-CSF) and equine copivirus (Eqcopivirus)) have recently been discovered in horses with respiratory signs. However, the clinical impact of these three equine parvoviruses has yet to be determined. Nasal fluid samples and blood from 667 equids with acute onset of fever and respiratory signs submitted to a diagnostic laboratory were analyzed for the presence of common equine respiratory pathogens (equine influenza virus, equine herpesvirus-1/-4, equine rhinitis A and B virus, S. equi subspecies equi) as well as EqPV-H, EqPV-CSF and Eqcopivirus by qPCR. An additional 87 clinically healthy horses served as controls. One hundred and seventeen sick horses tested qPCR-positive for at least one of the three parvoviruses. Co-infections with common respiratory pathogens and parvoviruses were seen in 39 sick equids. All 87 clinically healthy horses tested qPCR-negative for all tested common respiratory pathogens and 10 healthy horses tested qPCR-positive for one of the equine parvoviruses. When the frequency of detection for EqPV-H, EqPV-CSF and Eqcopivirus of equids with respiratory signs was compared to that of clinically healthy horses, the difference was not statistically significant (p > 0.05), suggesting that the three recently identified equine parvoviruses do not contribute to the clinical picture of equids with respiratory disease.

Natural Mucosal Barriers and COVID-19 in Children

COVID-19 is more benign in children compared to adults for unknown reasons. This contrasts with other respiratory viruses where disease manifestations are often more severe in children. We hypothesized that a more robust early innate immune response to SARS-CoV-2 may protect against severe disease and compared clinical outcomes, viral copies and cellular gene and protein expression in nasopharyngeal swabs from 12 children and 27 adults upon presentation to the Emergency Department. SARS-CoV-2 copies were similar, but compared to adults, children displayed higher expression of genes associated with interferon signaling, NLRP3 inflammasome, and other innate pathways. Higher levels of IFN-α2, IFN-γ, IP-10, IL-8, and IL-1β protein were detected in nasal fluid in children versus adults. Anti-SARS-CoV-2 IgA and IgG were detected in nasal fluid from both groups and correlated negatively with mucosal IL-18. These findings suggest that a vigorous mucosal immune response in children compared to adults contributes to favorable clinical outcomes.

Assessment of dispersion of airborne particles of oral/nasal fluid by high flow nasal cannula therapy

Background Nasal High Flow (NHF) therapy delivers flows of heated humidified gases up to 60 LPM (litres per minute) via a nasal cannula. Particles of oral/nasal fluid released by patients undergoing NHF therapy may pose a cross-infection risk, which is a potential concern for treating COVID-19 patients. Methods Liquid particles within the exhaled breath of healthy participants were measured with two protocols: (1) high speed camera imaging and counting exhaled particles under high magnification (6 participants) and (2) measuring the deposition of a chemical marker (riboflavin-5-monophosphate) at a distance of 100 and 500 mm on filter papers through which air was drawn (10 participants). The filter papers were assayed with HPLC. Breathing conditions tested included quiet (resting) breathing and vigorous breathing (which here means nasal snorting, voluntary coughing and voluntary sneezing). Unsupported (natural) breathing and NHF at 30 and 60 LPM were compared. Results Imaging: During quiet breathing, no particles were recorded with unsupported breathing or 30 LPM NHF (detection limit for single particles 33 μm). Particles were detected from 2 of 6 participants at 60 LPM quiet breathing at approximately 10% of the rate caused by unsupported vigorous breathing. Unsupported vigorous breathing released the greatest numbers of particles. Vigorous breathing with NHF at 60 LPM, released half the number of particles compared to vigorous breathing without NHF. Chemical marker tests: No oral/nasal fluid was detected in quiet breathing without NHF (detection limit 0.28 μL/m3). In quiet breathing with NHF at 60 LPM, small quantities were detected in 4 out of 29 quiet breathing tests, not exceeding 17 μL/m3. Vigorous breathing released 200–1000 times more fluid than the quiet breathing with NHF. The quantities detected in vigorous breathing were similar whether using NHF or not. Conclusion During quiet breathing, 60 LPM NHF therapy may cause oral/nasal fluid to be released as particles, at levels of tens of μL per cubic metre of air. Vigorous breathing (snort, cough or sneeze) releases 200 to 1000 times more oral/nasal fluid than quiet breathing (p < 0.001 with both imaging and chemical marker methods). During vigorous breathing, 60 LPM NHF therapy caused no statistically significant difference in the quantity of oral/nasal fluid released compared to unsupported breathing. NHF use does not increase the risk of dispersing infectious aerosols above the risk of unsupported vigorous breathing. Standard infection prevention and control measures should apply when dealing with a patient who has an acute respiratory infection, independent of which, if any, respiratory support is being used. Clinical trial registration ACTRN12614000924651

Novel Nasal Epithelial Cell Markers of Parkinson’s Disease Identified Using Cells Treated with α-Synuclein Preformed Fibrils

Parkinson’s disease (PD) is the most common neurodegenerative movement disorder, characterized by olfactory dysfunction in the early stages. α-Synuclein pathologies in the olfactory organs are shown to spread to the brain through the nose-brain axis. We first developed a nasal epithelial PD cellular model by treating RPMI-2650 cells with α-synuclein preformed fibrils (PFF). Upon uptake of PFF, RPMI-2650 cells showed mitochondrial proteome alteration and downregulation of parkin, which has previously been identified as a nasal biomarker of PD. Functional cluster analysis of differentially expressed genes in RPMI-2650 cells revealed various pathways affected by α-synuclein pathology, including the detection of chemical stimulus involved in sensory perception, olfactory receptor activity, and sensory perception of smell. Among genes that were most affected, we validated, by real-time quantitative PCR, the downregulation of MAP3K8, OR10A4, GRM2, OR51B6, and OR9A2, as well as upregulation of IFIT1B, EPN1, OR1D5, LCN, and OTOL1 in PFF-treated RPMI-2650 cells. Subsequent analyses of clinical samples showed a downregulation of OR10A4 and OR9A2 transcripts and an upregulation of IFIT1B in cells isolated from the nasal fluid of PD patients, as compared to those from the controls (cutoff value = 0.5689 for OR9A2, with 72.4% sensitivity and 75% specificity, and 1.4658 for IFIT1B, with 81.8% sensitivity and 77.8% specificity). Expression levels of these nasal PD markers were not altered in nasal fluid cells from SWEDD (scans without evidence of dopaminergic deficits) patients with PD-like motor symptoms. These nasal markers were significantly altered in patients of PD with hyposmia compared to the control hyposmic subjects. Our results validated the α-synuclein-treated nasal epithelial cell model to identify novel biomarkers for PD and suggest the utility of olfactory transcripts, along with olfactory dysfunction, in the diagnosis of PD.

Method Development and Validation of UV Spectrophotometric Method for the Quantitative Estimation of Curcumin in Simulated Nasal Fluid

Background Curcumin is a polyphenolic compound with numerous therapeutic activities. There is no validated method available for the quantitative estimation of curcumin in simulated nasal fluid. Objective The aim of present investigation was to develop a simple and precise UV visible spectrophotometric method for estimation of pure form of curcumin in simulated nasal fluid. Method Suitable solvent system was selected by estimation of curcumin at UV maxima of 421nm in simulated nasal fluid with two surfactants (tween 80 and sodium lauryl sulphate). The double beam UV visible spectrophotometer was used for measurement of absorption. The selected solvent system was further validated according to guidelines of international conference on harmonization (ICH), the analytical parameter like linearity, precision and accuracy etc. were studied. Results Simulated nasal fluid with tween 80 at 1% concentration satisfied all the conditions relative to Peak quality at the stated wavelength. In developed method, curcumin was found to be linear over selected concentration range of 5 to 60µg/ml with a correlation coefficient of 0.998. The accuracy was found to be in range of 99.51 –100.223%.The precision was found to be less than 2 in terms of % RSD. The LOD & LOQ were 0.3657 & 1.109 respectively. Conclusion The proposed method was found to be simple, sensitive and precise. The most important this method can be used for routine quality control analysis of curcumin with accuracy.

Assessment of dispersion of airborne particles of oral/nasal fluid by high flow nasal cannula therapy

Background Nasal High Flow (NHF) therapy delivers flows of heated humidified gases up to 60 LPM (litres per minute) via a nasal cannula. Particles of oral/nasal fluid released by patients undergoing NHF therapy may pose a cross-infection risk, which is a potential concern for treating COVID-19 patients. Methods Liquid particles within the exhaled breath of healthy participants were measured with two protocols: (1) high speed camera imaging and counting exhaled particles under high magnification (6 participants) and (2) measuring the deposition of a chemical marker (riboflavin-5-monophosphate) at a distance of 100 and 500 mm on filter papers through which air was drawn (10 participants). The filter papers were assayed with HPLC. Breathing conditions tested included quiet (resting) breathing and vigorous breathing (which here means nasal snorting, voluntary coughing and voluntary sneezing). Unsupported (natural) breathing and NHF at 30 and 60 LPM were compared. Results (1) Imaging: During quiet breathing, no particles were recorded with unsupported breathing or 30 LPM NHF (detection limit for single particles 33 microns). Particles were detected in 2 of 6 participants at 60 LPM quiet breathing at approximately 10% of the rate caused by unsupported vigorous breathing. Unsupported vigorous breathing released the greatest numbers of particles. Vigorous breathing with NHF at 60 LPM, released half the number of particles compared to vigorous breathing without NHF. (2) Chemical marker tests: No oral/nasal fluid was detected in quiet breathing without NHF (detection limit 0.28 microlitres/m3). In quiet breathing with NHF at 60 LPM, small quantities were detected in 4 out of 29 quiet breathing tests, not exceeding 17 microlitres/m3. Vigorous breathing released 200-1000 times more fluid than the quiet breathing with NHF. The quantities detected in vigorous breathing were similar whether using NHF or not. Conclusion During quiet breathing, 60 LPM NHF therapy may cause oral/nasal fluid to be released as particles, at levels of tens of microlitres per cubic metre of air. Vigorous breathing (snort, cough or sneeze) releases 200 to 1000 times more oral/nasal fluid than quiet breathing. During vigorous breathing, 60 LPM NHF therapy caused no statistically significant difference in the quantity of oral/nasal fluid released compares to unsupported breathing. NHF use does not increase the risk of dispersing infectious aerosols above the risk of unsupported vigorous breathing. Standard infection prevention and control measures should apply when dealing with a patient who has an acute respiratory infection, independent of which, if any, respiratory support is being used.