ABSTRACT
RNA external standards, although important to ensure equivalence across many microarray platforms, have yet to be fully implemented in the research community. In this article, a set of unique RNA external standards (or RNA standards) and probe pairs that were added to total RNA in the samples before amplification and labeling are described. Concentration-response curves of RNA external standards were used across multiple commercial DNA microarray platforms and/or quantitative real-time polymerase chain reaction (RT-PCR) and next-generation sequencing to identify problematic assays and potential sources of variation in the analytical process. A variety of standards can be added in a range of concentrations spanning high and low abundances, thereby enabling the evaluation of assay performance across the expected range of concentrations found in a clinical sample. Using this approach, we show that we are able to confirm the dynamic range and the limit of detection for each DNA microarray platform, RT-PCR protocol, and next-generation sequencer. In addition, the combination of a series of standards and their probes was investigated on each platform, demonstrating that multiplatform calibration and validation is possible.
Subject(s)
Models, Chemical , Oligonucleotide Array Sequence Analysis/methods , Oligonucleotide Array Sequence Analysis/standards , RNA Probes/chemistry , Reference StandardsABSTRACT
PURPOSE: In cooperation with JMS Co., Ltd. (Hiroshima, Japan), we have developed a new intraluminal coronary shunt tube to allow easier, safer, and more accurate off-pump coronary artery bypass grafting (OPCABG). DESCRIPTION: Between September 2000 and July 2002, the new shunt tube was used in 100 consecutive patients undergoing OPCABG. Patient characteristics, experimental data, and clinical results for our new shunt tube are provided. EVALUATION: Our new coronary shunt tube was easily implanted in nearly all (97.2%) target vessels during reconstructions. All 100 cases were performed completely during off-pump operation. Early postoperative coronary angiography was performed in all 100 cases, demonstrating excellent patency in arterial grafts (99.5%) and venous grafts (96.2%). The shunt tube displayed good flow rates under experimental conditions according to diameter, and effectively prevented ischemia during coronary arterial reconstructions in all cases. No target vessels were injured on insertion or removal of shunt tubes. Neither perioperative complications nor hospital deaths were encountered. CONCLUSIONS: This new shunt tube improves the safety, accuracy, and ease of OPCABG surgery.
Subject(s)
Coronary Artery Bypass, Off-Pump/instrumentation , Aged , Coronary Angiography , Equipment Design , Female , Humans , Male , Middle Aged , Myocardial Ischemia/diagnostic imaging , Myocardial Ischemia/surgery , Treatment Outcome , Vascular PatencyABSTRACT
BACKGROUND: Complete revascularization has been difficult in off-pump coronary artery bypass grafting (OPCAB). Hemodynamic deterioration often prevents access to the circumflex territory. This study presents instrumentation for accessing the circumflex territory, and our clinical experience. METHODS: From August 1999 through December 2002, 140 patients underwent OPCAB via sternotomy in our institution. The 114 requiring reconstruction of the circumflex artery are the subjects of this study. There were no exclusion criteria. A series of techniques and instruments were developed to provide access to the circumflex area while hemodynamic stability was preserved, including the left pericardial traction technique, compression of the right pericardium, a right sternal retractor, and a type of shunt tube. RESULTS: Patients received an average of 3.2 grafts (range, 2 to 6). Complete revascularization was achieved in 95% of the cases. Complications included respiratory insufficiency (0.8%), renal dysfunction (7%), and sternal wound infection (0.8%). Blood transfusions were required in 10 patients (8%). No patient suffered perioperative myocardial infarction or stroke. No operation was converted to cardiopulmonary bypass. There was no operative death. Predischarge angiography demonstrated a 99% patency rate. CONCLUSIONS: With our techniques and instruments, off-pump coronary revascularizaion of the circumflex area may be performed safely to achieve complete revascularization. Early clinical results are excellent, but long-term longitudinal follow-up is required to assess the future effectiveness of OPCAB procedure with our techniques.
