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BackgroundThe aim of this study is to evaluate the current state of ototoxicity monitoring for patients receiving cisplatin chemotherapy in an academic medical center with particular attention to how closely monitoring adheres to national ototoxicity guidelines.MethodsCase series including retrospective medical records review of patients (age > 18) treated with cisplatin at University of California Davis Medical Center between January 2014 and August 2017. Patient and ototoxicity related variables were analyzed. Patients that underwent a transfer of care during treatment and with less than 3 months of follow-up were excluded.ResultsThree hundred seventy-nine patients met study criteria, of which 104 (27.4%) had a prior history of hearing loss. Prior to treatment, 196 (51.7%) patients were counseled regarding the ototoxic nature of cisplatin and 92 (24.3%) patients had a pretreatment audiogram. During treatment, 91 (24%) patients had documented otologic complaints. Only 17 patients (4.5%) patients had an audiogram ordered during their cisplatin treatment period. 130 (34.3%) patients had otologic complaints following cisplatin treatment. Audiograms were ordered for 20 (7.8%), 13 (5.1%), and 16 (6.2%) patients at 1-month, 3-month, and 6-month follow-ups, respectively. No patients in the study cohort received baseline, treatment, and post-treatment audiograms as recommended by national ototoxicity monitoring protocols. Patients with Head and Neck Cancer (HNC) represented the largest subgroup that received cisplatin (n = 122, 32.2%) and demonstrated higher rates of ototoxicity counseling (n = 103, 84.4%) and pretreatment audiograms (n = 70, 57.4%) compared to the non HNC group (n = 36, 36.2%, P

Background: The AOAC Stakeholder Panel on Strategic Food Analytical Methods issued a call for methods in 2018 for the measurement of lactose in low-lactose and lactose-free products under Standard Method Performance Requirement (SMPR®) 2018.009. Megazyme's Lactose Assay Kit (K-LOLAC) was reviewed and accepted as a First Action Official MethodSM in 2020 (2020.08)., Objective: A collaborative study was conducted to evaluate the to evaluate the reproducibility of AOAC Official MethodSM2020.08 for the measurement of lactose concentration in low-lactose and lactose-free milk, milk products, and products containing dairy ingredients., Method: Samples are deproteinated and clarified by treatment with Carrez reagents, and then free glucose is removed using a glucose oxidase and catalase treatment system. Quantification of lactose is based on the hydrolytic activity of β-galactosidase, which hydrolyses lactose to glucose and galactose. Any remaining free D-glucose is first measured using a hexokinase (HK)/glucose 6-phosphate dehydrogenase (G-6PDH)/6-phosphogluconate dehydrogenase (6-PGDH) based assay procedure, and then β-galactosidase is added to hydrolyze the lactose in the same reaction vessel with concurrent measurement of the released D-glucose. The samples analyzed included a number of lactose-free and low-lactose milk samples, lactose-free infant formula, lactose-free milkshake, lactose-free adult nutritional drink, lactose-free cream, and lactose-free cheese., Results: All materials had repeatability relative standard deviations (RSDr) <7%. The reproducibility relative standard deviation (RSDR) varied from 3.8 to 14.9% with seven of the 10 test samples having an RSDR of <10%., Conclusions: The Lactose Assay Kit (K-LOLAC) meets the requirements for reproducibility set out under SMPR 2018.009., Highlights: The Lactose Assay (K-LOLAC) is a robust, simple, and reproducible method for analysis of lactose in foodstuffs and beverages., (© The Author(s) 2022. Published by Oxford University Press on behalf of AOAC INTERNATIONAL.)

Background: The AOAC Stakeholder Panel on Strategic Food Analytical Methods issued a call for methods for the measurement of lactose in low-lactose and lactose-free products under Standard Method Performance Requirement (SMPR®) 2018.009. Megazyme's Lactose Assay Kit (K-LOLAC) was developed specifically to address the need for accurate enzymatic testing in lactose-free samples., Objective: K-LOLAC was validated for measurement of lactose in low-lactose and lactose-free milk, milk products, and products containing dairy ingredients. A single-laboratory validation (SLV) of the method is reported., Method: K-LOLAC is an accurate and sensitive enzymatic method for the rapid measurement of lactose in low-lactose or lactose-free products. Validation analysis was performed on a sample set of 36 commercial food and beverage products and a set of 10 certified reference materials. Parameters examined during the validation included working range and linear range, selectivity, LOD, LOQ, trueness (bias), precision (repeatability and intermediate precision), robustness, and stability., Results: For all samples tested within the lower range (10-100 mg/100 g or mL), recoveries varied from 93.21-114.10%. Recoveries obtained for samples in the higher range (>100 mg/100 g or mL) varied from 94.44-108.28%. All materials had repeatability relative standard deviations (RSDr and RSDir) of <9%., Conclusions: The commercial K-LOLAC assay kit, as developed by Megazyme, meets the requirements set out under SMPR 2018.009., Highlights: K-LOLAC is a robust, quick, and easy method for analysis of lactose in foodstuffs and beverages., (© AOAC INTERNATIONAL 2021.)

Kombucha is a fermented, lightly effervescent sweetened black or green tea drink. It is marketed as a functional beverage based on its proposed health benefits. Kombucha is produced by fermenting tea using a "symbiotic colony of bacteria and yeast" (SCOBY). Kombucha is marketed as a non-alcoholic beverage, however due to the production process employed, there is a high possibility that the Kombucha products will contain low levels of ethanol. Kombucha is sold in a raw and unpasteurized form and, if kept at temperatures above 4 °C, the possibility exists that it will continue to ferment, producing ethanol. This possibility of continued fermentation may lead to an increase in ethanol content from levels below 0.5%ABV at time of production to higher levels at time of consumption. Thus, there is a potential for levels rising to greater than 0.5%ABV, the threshold for certification as a non-alcoholic beverage. It is essential that Kombucha manufacturers have the capacity to accurately and quickly test for ethanol in their products.  The Ethanol Assay Kit is an enzymatic test kit developed by Megazyme for the determination of ethanol in a variety of samples. The kit has been validated in a single laboratory for use with Kombucha fermented drinks, fruit juices, and low-alcohol beer samples. The commercially available Ethanol Assay Kit (Megazyme catalogue no. K-ETOH) contains all components required for the analysis. Quantification is based on the oxidation of ethanol to acetaldehyde by alcohol dehydrogenase and further oxidation of acetaldehyde by acetaldehyde dehydrogenase with conversion of NAD+ to NADH. The single laboratory validation (SLV) outlined in this document was performed on a sample set of eight different commercial Kombucha products purchased in Ireland, a set of five Cerilliant aqueous ethanol solutions, two BCR low-alcohol beer reference materials, two alcohol-free beer samples, and two fruit juice samples against SMPR 2016.001 (1). Parameters examined during the validation included Working range, Selectivity, Limit of Detection (LOD), Limit of Quantification (LOQ), Trueness (bias), Precision (reproducibility and repeatability), Robustness, and Stability. The Ethanol Assay is a robust, quick and easy method for the measurement of ethanol in Kombucha. Our data suggests this method is also reliable for similar matrices, such as low-alcohol beer and fruit juice. The assay meets all requirements set out in in AOAC SMPR 2016.001., (© AOAC INTERNATIONAL 2020.)

Background: In recent years there has been a surge in the number of commercially available lactose-free variants of a wide variety of products. This presents an analytical challenge for the measurement of the residual lactose content in the presence of high levels of mono-, di-, and oligosaccharides., Results: In the current work, we describe the development of a novel enzymatic low-lactose determination method termed LOLAC (low lactose), which is based on an optimized glucose removal pre-treatment step followed by a sequential enzymatic assay that measures residual glucose and lactose in a single cuvette. Sensitivity was improved over existing enzymatic lactose assays through the extension of the typical glucose detection biochemical pathway to amplify the signal response. Selectivity for lactose in the presence of structurally similar oligosaccharides was provided by using a β-galactosidase with much improved selectivity over the analytical industry standards from Aspergillus oryzae and Escherichia coli (EcLacZ), coupled with a 'creep' calculation adjustment to account for any overestimation. The resulting enzymatic method was fully characterized in terms of its linear range (2.3-113 mg per 100 g), limit of detection (LOD) (0.13 mg per 100 g), limit of quantification (LOQ) (0.44 mg per 100 g) and reproducibility (≤ 3.2% coefficient of variation (CV)). A range of commercially available lactose-free samples were analyzed with spiking experiments and excellent recoveries were obtained. Lactose quantitation in lactose-free infant formula, a particularly challenging matrix, was carried out using the LOLAC method and the results compared favorably with those obtained from a United Kingdom Accreditation Service (UKAS) accredited laboratory employing quantitative high performance anion exchange chromatography - pulsed amperometric detection (HPAEC-PAD) analysis., Conclusion: The LOLAC assay is the first reported enzymatic method that accurately quantitates lactose in lactose-free samples. © 2018 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry., (© 2018 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.)

endo-1,4-β-Xylanase (EC 3.2.1.8) is employed across a broad range of industries including animal feed, brewing, baking, biofuels, detergents and pulp (paper). Despite its importance, a rapid, reliable, reproducible, automatable assay for this enzyme that is based on the use of a chemically defined substrate has not been described to date. Reported herein is a new enzyme coupled assay procedure, termed the XylX6 assay, that employs a novel substrate, namely 4,6-O-(3-ketobutylidene)-4-nitrophenyl-β-4 5 -O-glucosyl-xylopentaoside. The development of the substrate and associated assay is discussed here and the relationship between the activity values obtained with the XylX6 assay versus traditional reducing sugar assays and its specificity and reproducibility were thoroughly investigated., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: The measurement of α-amylase (EC 3.2.1.1) in sprout-damaged grains is a crucial analysis yet a problematic one owing to the typically low α-amylase levels in ground wheat samples. A number of standardised methods such as the Falling Number method and the Ceralpha method exist which are routinely used for the assay of α-amylase. These methods, however, are either highly substrate-dependent or lack the required sensitivity to assess sprout damage., Results: Novel colorimetric and fluorometric reagents have been prepared (Amylase HR, Amylase SD, BzCNPG7 reagent and BzMUG7 reagent) for the direct and specific assay of α-amylase activity in sprout-damaged wheat. Assays employing these reagents have been developed and optimised to include a decolourisation step using activated charcoal. When used in a convenient assay format, Amylase SD--containing EtNPG7 (II) as the colorimetric substrate and α-glucosidase as the ancillary enzyme--was found to be an excellent reagent for the assessment of sprout damage in wheat with incubation times as short as 5 min., Conclusion: The assay using Amylase SD is completely specific for α-amylase. The use of the Amylase SD assay represents a sensitive and valid alternative to the traditionally used Falling Number values for the assessment of sprout damage in wheat samples., (© 2015 Society of Chemical Industry.)

Purpose of Review: This review will discuss the real-world risk factors involved in noise-induced hearing loss as a result of common and popular recreational activities prone to mid and high levels of noise exposure. Although there are currently no interventional measures available to reverse or mitigate preexisting hearing loss from noise, we discuss the vital importance of hearing loss prevention from noise exposure avoidance and reduction., Recent Findings: Despite a seeming understanding of the effects of noise exposure from various recreational activities and devices, a large percentage of the general public who is at risk of such noise-induced hearing loss still chooses to refrain from using hearing protection instruments., Summary: While occupational exposures pose the greatest traditional risk to hearing conservation in selected workers, recreational risk factors for noise-induced hearing loss may be more insidious in overall effect given the indifferent attitude of much of the general public and particularly our youths toward hearing protection during recreational activities. Active counseling regarding the consequences of excessive noise exposure and the potential benefits to hearing from usage of hearing protection instruments is critical to providing best possible care in the hearing health professions.

Specific and highly sensitive colourimetric and fluorometric substrate mixtures have been prepared for the measurement of pullulanase and limit-dextrinase activity and assays employing these substrates have been developed. These mixtures comprise thermostable α- and β-glucosidases and either 4,6-O-benzylidene-2-chloro-4-nitrophenyl-β-maltotriosyl (1-6) α-maltotrioside (BzCNPG3G3, 1) as a colourimetric substrate or 4,6-O-benzylidene-4-methylumbelliferyl-β-maltotriosyl (1-6) α-maltotrioside (BzMUG3G3, 2) as a fluorometric substrate. Hydrolysis of substrates 1 and 2 by exo-acting enzymes such as amyloglucosidase, β-amylase and α-glucosidase is prevented by the presence of the 4,6-O-benzylidene group on the non-reducing end D-glucosyl residue. The substrates are not hydrolysed by any α-amylases studied, (including those from Aspergillus niger and porcine pancreas) and are resistant to hydrolysis by Pseudomonas sp. isoamylase. On hydrolysis by pullulanase, the 2-chloro-4-nitrophenyl-β-maltotrioside (3) or 4-methylumbelliferyl-β-maltotrioside (4) liberated is immediately hydrolysed to D-glucose and 2-chloro-4-nitrophenol or 4-methylumbelliferone. The reaction is terminated by the addition of a weak alkaline solution leading to the formation of phenolate ions in solution whose concentration can be determined using either spectrophotometric or fluorometric analysis. The assay procedure is simple to use, specific, accurate, robust and readily adapted to automation., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

A specific and sensitive substrate for the assay of endo-1,4-β-glucanase (cellulase) has been prepared. The substrate mixture comprises benzylidene end-blocked 2-chloro-4-nitrophenyl-β-cellotrioside (BzCNPG3) in the presence of thermostable β-glucosidase. Hydrolysis by exo-acting enzymes such as β-glucosidase and exo-β-glucanase is prevented by the presence of the benzylidene group on the non-reducing end d-glucosyl residue. On hydrolysis by cellulase, the 2-chloro-4-nitrophenyl-β-glycoside is immediately hydrolysed to 2-chloro-4-nitrophenol and free d-glucose by the β-glucosidase in the substrate mixture. The reaction is terminated and colour developed by the addition of a weak alkaline solution. The assay procedure is simple to use, specific, accurate, robust and readily adapted to automation. This procedure should find widespread applications in biomass enzymology and in the specific assay of endo-1,4-β-glucanase in general., (Copyright © 2013 Elsevier Ltd. All rights reserved.)