RESUMEN
Balancer chromosomes contain multiple inversions that work to suppress crossing over and prevent recovery of most recombinant chromosomes, allowing for alleles to be kept long-term without selection. These balancers are incredible tools, but some alleles within larger inverted segments are still lost to rare double crossover events between the balanced and balancer chromosomes. This study details a new methodology of producing balancer chromosomes using CRISPR/Cas9 gene editing technology to create new inversions within the largest segment of the common X chromosome balancer, FM7c. We were able to create a new X chromosome balancer, FM8, and anticipate that this process can be used to not only create other balancers in Drosophila melanogaster, but other model organisms as well.
RESUMEN
OBJECTIVE: To prospectively determine if the current practice of radiologists' interpretation of post-ERCP spot images sent by endoscopists resulted in discrepancies in interpretation, affected subsequent management of patients, and resulted in additional costs. METHODS: A prospective analysis of 145 consecutive patients who underwent ERCP over the course of 4 months was performed. A separate endoscopist, not involved in the patient's care, reviewed the radiologist's report of the ERCP x-ray films to determine whether there was either concordance or discordance with the procedural findings. All patients' clinical courses were prospectively followed for a minimum of 6 months to determine whether clinical decision-making was affected by the radiologists' interpretation of the x-ray films. Secondarily, the cost of the current practice of postprocedure interpretation of ECRP radiographs was measured. SETTING: This study took place at University Hospitals of Cleveland, which is a tertiary care facility. RESULTS: In total, there were 61 (47%) discordant interpretations of 130 cholangiograms and 27 (38%) discordant interpretations of 72 pancreatograms, with an overall discordance between an endoscopist and a radiologist in 80 (55%) of the 145 cases. Clinical management was subsequently affected in 3 (2.1%) cases, all of which involved a discordant reading. In each of the 3 cases, further testing validated the gastroenterologist's initial findings at the time of the procedure. Radiologists were reimbursed $5395 for interpretation of ERCP x-ray films. Extrapolated over the course of a year, the reimbursement at this single tertiary care hospital would be greater than $16,000. Additional testing based on discordant reports resulted in $2510 of reimbursement for 3 patients. LIMITATION: The limitation of this study is that it reflects data from only one academic institution. CONCLUSIONS: Radiologists' interpretation of postprocedure ERCP films were inadequate, with a 47% discordance rate among cholangiograms and a 38% discordance rate among pancreatograms. The routine practice of postprocedure ERCP x-ray film interpretation by radiologists altered clinical practice in 2.1% of cases; subsequent care did not confirm radiologists' findings and imparted increased risk to the patients. This practice proved to be a misallocation of resources and should not be continued.
