A total of 1,002 urine specimens were evaluated by laser nephelometry. This technique was compared with both colony counts, done with a calibrated loop, and serial dilutions. For urine specimens containing between 10(4) and 10(5) bacteria per ml, laser nephelometry detected 75.4% of those detected by colony count and 65.6% of those detected by serial dilution. For specimens where the concentration of bacteria was greater than 10(5) per ml, laser nephelometry detected 95.8 and 92.4% of those detected by colony count and serial dilution, respectively. The mean detection time for bacteriuria varied from 1.57 h for more than 10(5) bacteria per ml to 4.47 h for more than 10(4) bacteria per ml. To determine the number of bacteria according to the voltage growth curve, the passage time at 3 V was used as an index. The mean passage time at 3 V decreased from 5.18 h for fewer than 10(4) bacteria per ml to 1.42 h for more than 10(6) bacteria per ml. The mean passage time at 3 V differed significantly for different concentrations of bacteria. Thus, this index allowed us to predict the number of bacteria in the urine specimens. Laser nephelometry has been used for many years for the immunological determination of proteins; it can now also be considered a tool for rapid screening in bacteriology.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC271029 | PMC |
http://dx.doi.org/10.1128/jcm.19.2.240-244.1984 | DOI Listing |
Methods Mol Biol
March 2024
Laboratory of Pathology, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA.
Lasers for light scattering measurement and fluorescence excitation are essential components of all flow cytometers. Flow cytometers now typically rely on multiple laser wavelengths allowing excitation of a constantly increasing variety of fluorescent probes. The expanding use of spectral flow cytometry to increase the magnitude of multiparametric analysis is also changing the significance of laser choice in cytometry.
View Article and Find Full Text PDFMult Scler Relat Disord
February 2024
Faculty of Medicine and Dentistry, Palacky University Olomouc, Czech Republic; University Hospital Olomouc Department of Neurology, Olomouc, Czechia.
J Fungi (Basel)
October 2023
Department of Dermatology, Jena University Hospital, Friedrich Schiller University, D-07747 Jena, Germany.
J Biophotonics
January 2024
Novosibirsk State University, Novosibirsk, Russian Federation.
Cell cultures are widely used in scientific research, biomedicine, and industry. When culturing, it is important to maintain certain conditions, including the concentration of cells. Monitoring of the culture growth and cell counting is an urgent task for the optimization of technological processes.
View Article and Find Full Text PDFAnn Clin Biochem
September 2023
Department of Molecular Oncology, Cancer Institute (WIA), Chennai, Tamil Nadu, India.
Background: Several studies have demonstrated the analytical sensitivity of MALDI-TOF mass spectrometry (MALDI-TOF MS) by immunoenrichment for M-protein analysis. We report the results of a novel, low-cost, reagent-based extraction process using acetonitrile (ACN) precipitation to enrich for κ and λ light chains which can be analysed by MALDI-TOF MS.
Methods: Institutional Ethics committee approval was obtained.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!