Laparoscopic Colorectal Surgery in the Emergency Setting: Trends in the Province of Ontario.

BACKGROUND: The purpose of this study was to examine the adoption trends of emergency laparoscopic colorectal surgery in the province of Ontario. STUDY DESIGN: We conducted a retrospective time-series analysis examining rates of emergency colorectal surgery among 10.5 million adults in Ontario, Canada from April 1, 2002 to December 31, 2009. We linked administrative claims databases and the Ontario Cancer Registry to assess procedure rates over time. Procedure trends were assessed using time-series analysis. RESULTS: Over the 8-year period, 29,676 emergency colorectal procedures were identified. A total of 2582 (8.7%) were performed laparoscopically and 27,094 (91.3%) were open. Open and laparoscopic patients were similar with respect age, sex, and Charlson Comorbidity Index. The proportion of surgery for benign (63.8% of open cases vs. 65.6% laparoscopic, standardized difference=0.04) and malignant disease (36.2% open vs. 34.4% laparoscopic, standardized difference=0.04) was equal between groups. The percentage of emergency colorectal surgery performed laparoscopically increased from 5.7% in 2002 to 12.0% in 2009 (P<0.01). The use of laparoscopy increased for both benign and malignant disease. Statistically significant upward trends in laparoscopic surgery were seen for inflammatory bowel disease (P<0.01), obstruction (P<0.01), and colon cancer (P<0.01). From 2002 to 2009, annual procedure rates increased at a greater rate in nonacademic centers (P<0.01). CONCLUSIONS: Laparoscopic emergency colorectal surgery has increased significantly between 2002 and 2009 for both benign and malignant disease and for a wide range of diagnoses. This was driven in part by steadily rising usage of laparoscopy in nonacademic centers.

Expression of circadian rhythm genes in gonadotropin-releasing hormone-secreting GT1-7 neurons.

The center for circadian rhythms in mammals is the suprachiasmatic nucleus (SCN) of the hypothalamus, composed of single cell circadian oscillators driven by a transcriptional/translational feedback loop where clock proteins drive clock gene expression. These genes are expressed in peripheral tissues and several brain areas outside the SCN. It is likely that some peripheral oscillators are synchronized by the SCN. The pineal hormone melatonin plays an important role in the entrainment of circadian rhythms through feedback to the SCN. Melatonin also plays a role in reproduction, including direct effects on GnRH-secreting GT1-7 neurons. The intrinsic rhythmicity of GnRH neurons suggests that these neurons may express the components of the circadian oscillator. Using the GT1-7 cell line, we demonstrate expression of the circadian rhythm genes, clock, BMAL1,timeless (tim), period1,period2, cryptochrome1, andcryptochrome2. Furthermore, semiquantitative RT-PCR demonstrates that BMAL1, period1, andperiod2 as well as GnRH mRNAs are expressed with a circadian-like rhythm after synchronization over 54 h. With available antibodies, we demonstrated CLOCK, BMAL1, and PERIOD1 protein expression in these cells, with BMAL1 protein levels showing a rhythmic expression pattern. In addition, receptors for melatonin, mt1 and MT2, also show a circadian expression pattern in the GT1-7 cells, and their expression is down-regulated by melatonin treatment. These findings suggest that the components of the clock machinery in mammals may play a role in GnRH neuronal function.