Biofilms are ubiquitous and play an essential role in both environmental processes and hospital infections. Standard methods are not capable of quantifying biomass concentration in dilute suspensions. Furthermore, standard techniques cannot differentiate biomass composition. In this study, a user-friendly technique was developed for measuring biomass cell and polymer content in detached biofilms using a standard coulter counter. The method was demonstrated for an environmentally relevant strain of Pseudomonas aeruginosa (Schroeter) Migula grown in a bioreactor and also for a medically relevant strain of P. aeruginosa (PAO1) grown on standard growth pegs. Results were compared and validated by standard assays, including EPA method 1684 for measuring biomass, microscopic direct counts, and a crystal violet staining assay. The minimum detection limit for the coulter counter method (0.07 mg-biomass L(-1)) was significantly lower than the EPA method 1684 (1.9 ± 0.4 mg/L) and the crystal violet assay (1.1 ± 0.2 mg L(-1)). However, the coulter counter method is limited to dilute biomass samples (below 204 ± 16 mg L(-1)) due to clogging of the aperture tube. While biomass measurements are useful, the major advantage of the coulter counter method is the ability to directly determine EPS, cell, and aggregate fractions after mild chemical treatment. The rapid technique (4-5 min per sample) was used to measure biomass fractions in dispersed P. aeruginosa (Schroeter) and PAO1 biofilms. This technique will be critical for understanding biofilm formation/dispersal.
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http://dx.doi.org/10.1016/j.mimet.2013.07.022 | DOI Listing |
Asian J Transfus Sci
December 2024
HORIBA India Pvt. Ltd, HORIBA ABX SAS, Montpellier, France.
Background And Objectives: Objective of the study is to explore the possibility of utilization of seven part fully automated hematology analyzer for enumeration of residual leukocytes (residual white blood cells [rWBCs]) in leukoreduced packed red cells (LR-PRCs) prepared from whole blood at a blood center as an alternate to the gold standard method, flow cytometry. In this study, we evaluate the performance characteristic of hematology analyzer against flow cytometry for the estimation of rWBCs in 39 LR-PRC units.
Materials And Methods: PRCs prepared from whole blood donations by 39 donors were leukoreduced and their volumes were noted.
Ultrasound Med Biol
February 2025
Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, USA; Medical Sciences Program, University of Cincinnati, Cincinnati, OH, USA; Department of Biomedical Engineering, University of Cincinnati, Cincinnati, OH, USA; Department of Pediatrics Heart Institute, University of Cincinnati, Cincinnati, OH, USA. Electronic address:
Objective: Acoustic droplet vaporization (ADV) is the liquid-to-gas phase transition of perfluorocarbon (PFC) droplets to microbubbles upon ultrasound insonation. After ADV, gases dissolved in the surrounding fluid diffuse into microbubbles, enabling oxygen scavenging. Characterization of oxygen scavenging and transition efficiency (TE) in whole blood has so far been limited.
View Article and Find Full Text PDFInt J Lab Hematol
February 2025
SIPMEL Castelfranco Veneto, Castelfranco Veneto, Italy.
Introduction: Hereditary spherocytosis (HS) is a congenital haemolytic disorder, resulting from plasma membrane protein deficiency of red blood cells (RBCs). Typical pathological signs are anemia, jaundice, and splenomegaly; in newborns, jaundice is the main symptom.
Material And Methods: This study focused on the state of art about the HS diagnosis, from traditional to innovative methods, including diagnostic algorithms that can be applied for pediatric and adult patients, for different laboratory diagnostic levels.
Sci Prog
September 2024
Department of Ophthalmology and Vision Science, Eye and ENT Hospital, Fudan University, Shanghai, People's Republic of China.
Objectives: Silicone oil (SO) is a commonly used intraocular tamponade in the treatment of rhegmatogenous retinal detachment (RRD). SO emulsification is a common complication after SO injection. This study aimed to investigate correlations between SO emulsification signs on ultrasound biomicroscopy (UBM) and the real number/size of SO droplets.
View Article and Find Full Text PDFJ Ind Microbiol Biotechnol
January 2024
Faculdade de Engenharia de Alimentos, Universidade Estadual de Campinas, Rua Monteiro Lobato 80, 13083-862, Campinas, SP, Brazil.
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