Laparoscopic right colectomy vs laparoscopic-assisted colonoscopic polypectomy for endoscopically unresectable polyps: a randomized controlled trial.

AIM: A randomized controlled trial (RCT) was conducted to test the null hypothesis that there is no difference in complication rates and length of stay (LOS) between laparoscopic right colectomy (LRC) and laparoscopic-assisted colonoscopic polypectomy (LACP) for endoscopically unresectable polyps of the right colon. METHOD: A single-centre RCT (NCT01986699) was conducted on patients with polyps of the right colon deemed by the gastroenterologist to be unresectable. Patients underwent a repeat colonoscopy with biopsy by an interventional endoscopist and were allocated to LRC or LACP. Patients with a nonlift sign, dysplasia, adenocarcinoma, inflammatory bowel disease or familial adenomatous polyposis were excluded from the trial. The study was powered to detect a 73% difference in the LOS which required 17 patients in each arm with an α error of 0.05 and a power of 95%. RESULTS: Thirty-four patients were comparable for age (P = 0.919), gender (P = 0.364), body mass index (P = 0.634), American Society of Anesthesiologists class (P = 0.388) and previous abdominal surgery (P = 0.366). There was no significant difference in the preoperative morphology (P = 0.485), location (P = 0.297), size (P = 0.690) or histology of the polyps (P = 0.779). LRC patients experienced a longer operating time (180 vs 90 min; P = 0.001), required more intravenous infusion (3.1 vs 2.0 l; P = 0.025), took significantly longer to pass flatus (2.88 vs 1.44 days; P < 0.001), resumed solid food later (3.94 vs 1.69 days; P < 0.001) and had a longer postoperative LOS (4.94 vs 2.63 days; P < 0.001). Postoperative complications (P = 0.656), readmissions (P = 0.5) and reoperations (P = 0.5) did not differ. Final size (P = 0.339) and histology (P = 0.104) of the polyps did not differ. There were four cancers in the LRC arm. At follow-up colonoscopy with biopsy of the scar in 10 patients at 15.3 months, one patient had recurrence of the polyp at the site of the previous LACP. CONCLUSION: LACP and LRC had similar complication rates, but LOS was shorter after LACP.

Selective use of single-photon emission computed tomography myocardial perfusion imaging in a chest pain center.

Emergency department chest pain centers (CPCs) vary in their approach to patients with chest pain and nonischemic electrocardiograms (ECG). Although single-photon emission computed tomography (SPECT) myocardial perfusion imaging has been evaluated in this setting, both acutely at rest and after stress, we questioned its application in all patients. We prospectively evaluated the utility of selective SPECT imaging in a CPC (i.e., rest SPECT for ongoing pain, stress SPECT if unable to undergo exercise electrocardiography) and its impact on the overall disposition of all emergency department chest pain patients. Over 3 years, 2,601 patients were evaluated in a CPC (2,211 [85%] were sent home, 390 [15%] were hospitalized). Of 390 CPC patients hospitalized, 182 (47%) were diagnosed with coronary artery disease at the time of hospital discharge. Only 28 patients (1.1%) had an acute myocardial infarction. After 3 years, the proportion of all chest pain patients hospitalized and those diagnosed as "rule-out myocardial infarction" decreased from 53% to 41% and 32% to 18% of all chest pain patients, respectively (both p <0.0001). Overall, 906 patients (35%) required SPECT imaging to complete the CPC evaluation. Had SPECT imaging not been performed selectively, and all 906 patients been admitted, 762 (29%) would have been hospitalized unnecessarily based on the final diagnoses. Alternatively, sending all these patients home would have resulted in 144 (6%) inappropriate discharges of patients with coronary artery disease. A CPC protocol using the selective use of SPECT imaging permits the complete evaluation of all patients in the CPC, significantly reduces hospitalizations for chest pain, and restricts hospital admission to more appropriate patients.

Chymotrypsin gene expression in rat peripheral organs.

Prior studies have revealed the presence of chymotrypsinlike protease in peripheral organs, although no definitive evidence for the synthesis of this enzyme in tissue other than the pancreas is available. In an attempt to detect chymotrypsinogen mRNA in peripheral organs, a fragment of the pancreatic chymotrypsin mRNA from rat was amplified using PCR. The sequence was identified as a portion of the rat chymotrypsin B gene overlapping exon 5 through exon 7. It was subcloned into the pGEM-4Z vector and used as a template for the vitro transcription of an antisense riboprobe. Using ribonuclease protection and Northern blot analyses, chymotrypsin mRNA was detected in the rat pancreas, stomach, duodenum, ovary, and spleen. Monoclonal and polyclonal antisera against chymotrypsin detected chymotrypsinlike immunoreactivity in rat and human pancreas, rat stomach, duodenum and jejunum. Electrophoresis and immunoblotting revealed chymotrypsin-chymotrypsinogen bands (25-29 kDa) in the stomach and duodenum. Synthesis of a potent protease such as chymotrypsin in tissue other than pancreas is significant, suggesting a potential physiological and/or pathological role in these tissues.

Beta-amyloid augments platelet aggregation: reduced activity of familial angiopathy-associated mutants.

The beta-amyloid (A beta) peptide is present both in serum and in platelets, however it is unclear whether A beta plays a role in platelet function. We have now investigated the effects of soluble A beta on platelet function and have found that low levels (0.1-1 nM) of soluble A beta augment ADP-dependent platelet aggregation and translocation of focal adhesion kinase to the platelet cytoskeleton. Addition of A beta to gel-filtered platelets along with concentrations of adenosine diphosphate (ADP) producing submaximal aggregation responses increased the aggregation response by over 2-fold depending on the ADP:A beta ratios. The structure activity requirements for A beta activity showed intriguing constraints. Only full length A beta has significant activity. Truncated A beta peptides, such as A beta(1-16) or A beta(25-35), or reverse A beta(40-1) all show little or no activity. We also examined the activity of mutant A beta peptides, corresponding with the APP(692A-G) and APP(693E-Q) (at A beta21 and A beta22, respectively) which are found in familial Alzheimer's disease and hereditary cerebral hemorrhagic amyloidosis, Dutch type (HCHWA-D), and found that these peptides showed little or no activity. These results suggest that A beta interacts with platelets in a highly specific manner and may play a role in regulating platelet function.