25 resultados para real-time monitoring
Resumo:
The plasma membrane Ca2+ pump is a key regulator of cytosolic free Ca2+. Recent studies have demonstrated the dynamic expression of the plasma membrane Ca2+ pump in a variety of cell types. Furthermore, alterations in plasma membrane calcium pump activity have now been implicated in human disease. In this study, the development of a technique to quantitatively assess mRNA expression of the human plasma membrane Ca2+ ATPase (PMCA1) isoform of the plasma membrane Ca2+ pump, using a real-time reverse transcriptase-polymerase chain reaction (real-time RT-PCR) assay in a human breast epithelial cell line (MCF-7) is described. The sequences of the PMCA1 primers and probe for real-time RT-PCR are presented. The results also indicate that PMCA1 mRNA can be normalized to both 18S ribosomal RNA (18S rRNA) and human glyceraldehyde-3-phosphate dehydrogenase (hGAPDH) in MCF-7 cells. Real-time RT-PCR will be most useful in assessing PMCA1 mRNA expression in cases where only low amounts of RNA are available and/or when numerous samples must be assessed simultaneously. (C) 2001 Elsevier Science Inc. All rights reserved.
Resumo:
The detection of Neisseria gonorrhoeae by the polymerase chain reaction (PCR) is now recognized as a sensitive and specific method of diagnosing infection by the organism. In this Study 152 urine specimens were examined for N. gonorrhoeae by a real-time PCR method using the LightCycler platform and results were compared to an in-house PCR assay using an ELISA-based detection method. N. gonorrhoeae DNA was detected in 29 (19%) specimens by LightCycler PCR (LC-PCR) and in 31 (20%) specimens by the in house PCR method. The LightCycler assay proved to be specific and 94% sensitive when compared to the in house PCR method. These features combined with the rapid turn-around time for results makes the LC-PCR particularly suitable for the detection of N. gonorrhoeae in a routine clinical laboratory. (C) 2002 Elsevier Science Inc. All rights reserved.
Resumo:
Program compilation can be formally defined as a sequence of equivalence-preserving transformations, or refinements, from high-level language programs to assembler code, Recent models also incorporate timing properties, but the resulting formalisms are intimidatingly complex. Here we take advantage of a new, simple model of real-time refinement, based on predicate transformer semantics, to present a straightforward compilation formalism that incorporates real-time constraints. (C) 2002 Elsevier Science B.V. All rights reserved.
Resumo:
The study of viral-based processes is hampered by (a) their complex, transient nature, (b) the instability of products, and (c) the lack of accurate diagnostic assays. Here, we describe the use of real-time quantitative polymerase chain reaction to characterize baculoviral infection. Baculovirus DNA content doubles every 1.7 h from 6 h post-infection until replication is halted at the onset of budding. No dynamic equilibrium exists between replication and release, and the kinetics are independent of the cell density at the time of infection. No more than 16% of the intracellular virus copies bud from the cell. (C) 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 476-480, 2002; DOI 10.1002/bit.10126.
Resumo:
The refinement calculus is a well-established theory for deriving program code from specifications. Recent research has extended the theory to handle timing requirements, as well as functional ones, and we have developed an interactive programming tool based on these extensions. Through a number of case studies completed using the tool, this paper explains how the tool helps the programmer by supporting the many forms of variables needed in the theory. These include simple state variables as in the untimed calculus, trace variables that model the evolution of properties over time, auxiliary variables that exist only to support formal reasoning, subroutine parameters, and variables shared between parallel processes.