Increased rate of hair regrowth in mice with constitutive overexpression of Del1.

BACKGROUND: Developmental endothelial locus (Del)1 is a secreted extracellular matrix-associated protein that stimulates angiogenesis through integrin binding and is implicated in vasculogenesis. We hypothesized that increased expression of an angiogenic factor would lead to enhanced wound healing. MATERIALS AND METHODS: Transgenic mice had Del1 cloned behind a keratin 14 promoter (K14-Del1) to drive constitutive expression in basal keratinocytes. Transgenic animals and wild-type litter mates underwent excisional wounding or depilation, and tissues were harvested at various time points. Wound healing and hair regrowth were assessed by photography, histology, and immunohistochemistry. For injection experiments, purified Del1 protein was injected in the flanks of wild-type mice with carrier on the contralateral flank as a control. Del1 expression during hair development was performed using transgenic mice with a LacZ cassette introduced downstream from the native promoter. RESULTS: K14-Del1 animals appeared normal and healed excisional wounds normally but demonstrated an increased rate of hair regrowth after wound healing. Using depilation experiments to specifically address hair follicle growth, we found increased hair regrowth was independent of wounding. This was confirmed by injection of purified Del1 protein. During normal hair anagenesis, Del1 is expressed in the root of the hair follicle. CONCLUSIONS: Constitutive expression of Del1 in skin does not affect skin vascularity or improve wound healing. Surprisingly, we found the primary effect of constitutive Del1 expression in the basal keratinocytes was increased hair growth following induction of anagenesis. During normal hair anagenesis, we see expression of Del1 in the root of the hair follicle suggesting it may function there to stimulate hair growth.

Orogastric tube complications in laparoscopic Roux-en-Y gastric bypass.

BACKGROUND: Recent national efforts have focused on improving patient safety in surgical procedures including examining adverse events. An adverse event in laparoscopic Roux-en-Y gastric bypass (LRYGBP) which has not received much scrutiny involves orogastric tube complications during gastric pouch formation. METHODS: Retrospective review was conducted of all LRYGBPs (n=727) performed by 5 surgeons over 5 years at 2 institutions. Cases with intraoperative orogastric tube (OGT) related complications (n=9) were identified. RESULTS: 9 patients (1.2%) had preventable orogastric tube-related complications. Mean patient demographics were as follows: age 47 years, female 56%, pre-op BMI 52 kg/m(2), co-morbidities 3.5 and mortality 0%. 7 of 9 patients' cases were complicated by stapling of an orogastric tube during gastric pouch formation. The remaining 2 patients had complications involving suturing of the Levacuator tube during gastrojejunostomy formation. All complications required gastric pouch or anastomotic revision. 2 patients required conversion to an open procedure, 2 required re-operation for anastomotic leak, and 1 had respiratory failure and prolonged hospital stay. CONCLUSION: Orogastric tube complications can occur during laparoscopic RYGBP, but are seldom reported and can be associated with significant morbidity. Treatment options are dependent upon the situation. More importantly, prevention strategies must include constant communication with the anesthesiologist and removal or manipulation of an OGT prior to stapling or suturing, use of large bore OGTs for increased visual or tactile recognition, retraction of the OGT proximal to the anastomosis during gastrojejunal construction and employing alternatives to esophageal temperature probes (i.e. Foley temperature probes).

Laparoscopic Roux-en-Y gastric bypass: differences in outcome between attendings and assistants of different training backgrounds.

BACKGROUND: Laparoscopic Roux-en-Y gastric bypass (LRYGBP) is associated with a significant learning curve. We hypothesize that differences in surgeon and assistant training backgrounds may significantly impact outcomes during the learning curve. METHODS: Retrospective analysis was performed on patients undergoing LRYGBP at an academic medical center between January 1998 and August 2003. Operations were performed by surgeons with different training backgrounds: without formal laparoscopic fellowship (S1, n=95); immediately following laparoscopic fellowship (S2, n=100); and with extensive laparoscopic experience post fellowship (S3, n=88). First assistants were attendings, fellows, or residents. The variables analyzed included demographics, operative times, estimated blood loss (EBL), rate of conversion, length of stay (LOS), ICU stay, re-operation/re-admission rate, and complications. Results were analyzed by ANOVA and Fisher's exact test. RESULTS: There were significant differences among surgeons of different training backgrounds in EBL, LOS, rate of ICU admission, and intraoperative and late complications rates. Among assistants of different training levels, there were significant differences in operative time, EBL, intraoperative complication rates and re-admission rates. CONCLUSIONS: Differences in training background of the surgeons resulted in significant differences in outcome, including EBL, LOS, ICU admission and intraoperative and late complication rates. Lower assistant training levels significantly impacted efficiency through lengthened operative times and increased EBL, as well as increased intraoperative complication rates and re-admission rates. Our results suggested that participating in a laparoscopic fellowship and operating with a more experienced assistant may improve outcomes during the learning curve.