Two methods for the detection of important human pathogens, Cryptosporidium parvum and Helicobacter pylori, were investigated: a fiber optic biosensor, and real time PCR. The mechanism for specific detection in both methods is recognition of specific DNA sequences in the target organisms. The biosensor that was used, the Analyte 2000, was originally developed for the detection of chemicals. It utilizes a fiber optic wave guide that propagates an evanescent light wave of very specific wavelength. The light excites fluorescent molecules bound to the waveguide, but not in the bulk solution, which theoretically enhances signal while reducing background interference. Attempts to develop this system for the detection of DNA were not successful due to poor detection of the target molecules. An assay analogous to a sandwich immunoassay was designed for use on the Analyte 2000. Specific oligonucleotide probes were designed to bind to the waveguides via biotin-streptavidin interaction, and were used to capture the target DNA. Pure target DNA representing unique genes in the organisms were synthesized by PCR. Detection of captured DNA was then attempted using an oligonucleotide detection probe designed to bind to the target. Two detection systems were employed: an indirect signal amplification system based on biotin-tyramide deposition, or direct detection of fluorescent signal from Cy-5 molecules. In all experiments performed there was very little difference between the signal generated with or without the target molecules. Many experiments were conducted to attempt to identify reasons for the poor signal. Signal was only of any significance when target amplicons were internally labeled with Cy-5 by PCR. Real time PCR as a method to detect the pathogens was also investigated. Though the PCR technique itself is very rapid, DNA extraction and purification requires preparation time. Filtration of up to one liter of well water, followed by concentration and "cleaning" Helicobacter pylori cells by immunomagnetic separation, was used to detect H. pylori seeded in a water source. Following cell lysis, the extracted DNA could be used directly in conventional PCR targeting the 16S rRNA gene to detect less than 265 cells per liter of water. DNA purification was not required for this level of detection. Initial studies to amplify lysed cells by real time PCR indicated that an incorrect product was made. When purified DNA was used for real time PCR, the correct product was produced from DNA representing as few as 100 cells. This publication can be purchased and downloaded via Pay Per View on Water Intelligence Online - click on the Pay Per View icon below
Water, with its simple molecular structure, reveals a complex nature upon interaction with other molecules and surfaces. Water at Interfaces: A Molecular Approach provides a broad, multidisciplinary introduction to water at interfaces, focusing on its molecular characteristics. The book considers interfaces at different length scales from single water molecules to involvement of large numbers of water molecules, and from one-dimensional to three-dimensional interfaces. It begins with individual water molecules, describing their basic properties and the fundamental concepts that form the basis of this book.
This book provides a detailed review of the modern theories dealing with the structure and properties of water. It also presents an analysis of the research on the effect of activated water on biological systems such as animals, microorganisms, and plants. The results of experiments on the influence of activated water on "pure" microbiological cultures and their natural associations are described, the studies being carried out under both aerobic and anaerobic conditions.The results demonstrate a significant influence of activated water on higher plants (vegetable crops), sterile plants, and callus tissues. It is shown that the activation of water under definite conditions gives rise to the appearance of very strong bactericidal properties: activated water inhibits the development of pathogenic microbiological cultures by tens and hundreds of times more strongly, and can be used for sterilization. In addition, a potent positive effect of activated water on the prevention and treatment of cancer in mice has been observed, and its efficacy compared to that of chemotherapy is discussed in the book.The information provided in this book is supported by intensive experimental data and developed theories. The research programs were conducted at the authors' laboratories in Ukraine and Russia as well as at research facilities located in the USA.
"Like every other home, it has its own secrets. Like every other home, there are lies and deceits crawling around. And just like every other home, there's always a hidden story."
Water Use Management, and Planning in the United States is designed with new college classes on water resources in mind. It provides information on hydrology, biology, geology, economics, and geography along with historical water policies and regional regulations. The text reflects the transdisciplinary nature of water resources management, moving between descriptive discussions and quantitative analysis to bridge the social and physical sciences. Also providedare frequent case studies and examples to illustrate real-world applications, and includes sidebars throughout to reinforce major points. This book is a result of the authors years of teaching, giving a prescription for an intelligent integrated systemsapproach to water resources management.