Illuminating Bacterial Contamination in Water Sources: The Power of Fluorescence-Based Methods.

Bacterial contamination of water sources is a significant public health concern, and therefore, it is important to have accurate and efficient methods for monitoring bacterial concentration in water samples. Fluorescence-based methods, such as SYTO 9 and PI staining, have emerged as a promising approach for real-time bacterial quantification. In this review, we discuss the advantages of fluorescence-based methods over other bacterial quantification methods, including the plate count method and the most probable number (MPN) method. We also examine the utility of fluorescence arrays and linear regression models in improving the accuracy and reliability of fluorescence-based methods. Overall, fluorescence-based methods offer a faster, more sensitive, and more specific option for real-time bacterial quantification in water samples.

Device-handling study of a novel breath-actuated inhaler, Synchrobreathe®, versus a pMDI.

INTRODUCTION: Synchrobreathe®, a new-generation, novel breath-actuated inhaler (BAI) can address the key issues arising during the use of both pressurised metered dose inhalers ([pMDIs]; hand-breath coordination) and dry powder inhalers ([DPIs]; high inspiratory flow required) with respect to optimal drug deposition. MATERIALS AND METHODS: This was an open-label, prospective, 2-week, multicentre study that assessed device handling, ease of use, errors and participant perception regarding the use of Synchrobreathe® versus a pMDI in patients with chronic obstructive pulmonary disease (COPD) (n = 162) or asthma (n = 239) and inhaler-naïve healthy volunteers (n = 59). Ability to use the device without errors at the first attempt, total number of errors before and after training, time taken to use the device correctly and total number of training sessions, and number of attempts to perform the correct technique on Day 1 and Day 14 were evaluated. Device handling and preference questionnaires were also administered on Day 14. RESULTS: Of 460 participants, 421 completed the study. The number of participants using Synchrobreathe without any error after reading the patient information leaflet (PIL) was significantly low (p < 0.05) on Day 1. On Day 14, significantly more number of participants used Synchrobreathe without any error (p < 0.001). The total number of errors before and after training with Synchrobreathe was significantly less (p < 0.001). The average time required to perform the inhalation technique correctly (p < 0.01) and the total number of attempts (P < 0.001) with Synchrobreathe were significantly lower. The average number of attempts to inhale correctly was significantly (p < 0.001) less with Synchrobreathe on Day1 and Day 14. Most participants rated Synchrobreathe as their choice of inhaler. CONCLUSION: Synchrobreathe is an easy-to-use and easy-to-handle device with significantly less number of errors, which may have positive implications for disease control in asthma and COPD.

Point-of-care breath test for biomarkers of active pulmonary tuberculosis.

RATIONALE: Volatile organic compounds (VOCs) in breath provide biomarkers of tuberculosis (TB) because Mycobacterium tuberculosis manufactures VOC metabolites that are detectable in the breath of infected patients. OBJECTIVES: We evaluated breath VOC biomarkers in subjects with active pulmonary TB, using an internet-linked rapid point-of-care breath test. METHODS: 279 subjects were studied at four centers in three countries, Philippines, UK, and India, and data was analyzed from 251 (130 active pulmonary TB, 121 controls). A point-of-care system collected and concentrated breath and air VOCs, and analyzed them with automated thermal desorption, gas chromatography, and surface acoustic wave detection. A breath test was completed in 6 min. Chromatograms were converted to a series of Kovats Index (KI) windows, and biomarkers of active pulmonary TB were identified by Monte Carlo analysis of KI window alveolar gradients (abundance in breath minus abundance in room air). MEASUREMENTS AND MAIN RESULTS: Multiple Monte Carlo simulations identified eight KI windows as biomarkers with better than random performance. Four KI windows corresponded with KI values of VOCs previously identified as biomarkers of pulmonary TB and metabolic products of M. tuberculosis, principally derivatives of naphthalene, benzene and alkanes. A multivariate predictive algorithm identified active pulmonary TB with 80% accuracy (area under curve of receiver operating characteristic curve), sensitivity=71.2%, and specificity = 72%. Accuracy increased to 84% in age-matched subgroups. In a population with 5% prevalence, the breath test would identify active pulmonary TB with 98% negative predictive value and 13% positive predictive value. CONCLUSIONS: A six-minute point-of-care breath test for volatile biomarkers accurately identified subjects with active pulmonary TB.