Daniel A. DeUgarte

IN VITRO DIFFERENTIATION OF HUMAN PROCESSED LIPOASPIRATE CELLS INTO EARLY NEURAL PROGENITORS

Human processed lipoaspirate (PLA) cells are multipotent stem cells, capable of differentiating into multiple mesenchymal lineages (bone, cartilage, fat, and muscle). To date, differentiation to nonmesodermal fates has not been reported. This study demonstrates that PLA cells can be induced to differentiate into early neural progenitors, which are of an ectodermal origin. Undifferentiated cultures of human PLA cells expressed markers characteristic of neural cells such as neuron-specific enolase (NSE), vimentin, and neuron-specific nuclear protein (NeuN). After 2 weeks of treatment of PLA cells with isobutylmethylxanthine, indomethacin, and insulin, about 20 to 25 percent of the cells differentiated into cells with typical neural morphologic characteristics, accompanied by increased expression of NSE, vimentin, and the nerve-growth factor receptor trk-A. However, induced PLA cells did not express the mature neuronal marker, MAP, or the mature astrocyte marker, GFAP. It was also found that neurally induced PLA cells displayed a delayed-rectifier type K+ current (an early developmental ion channel) concomitantly with morphologic changes and increased expression of neural-specific markers. The authors concluded that human PLA cells might have the potential to differentiate in vitro into cells that represent early progenitors of neurons and/or glia.

Trends and Outcomes of Adolescent Bariatric Surgery in California, 2005–2007

OBJECTIVE: The goal of this study was to evaluate trends, and outcomes of adolescents who undergo bariatric surgery. PATIENTS AND METHODS: Patients younger than 21 years who underwent elective bariatric surgery between 2005 and 2007 were identified from the California Office of Statewide Health Planning and Development database. Multivariate logistic regression was used to identify factors associated with the type of surgery. RESULTS: Overall, 590 adolescents (aged 13–20 years) underwent bariatric surgery in 86 hospitals. White adolescents represented 28% of those who were overweight but accounted for 65% of the procedures. Rates of laparoscopic adjustable gastric banding (LAGB) increased 6.9-fold from 0.3 to 1.5 per 100 000 population (P < .01), whereas laparoscopic Roux-en-Y gastric bypass (LRYGB) rates decreased from 3.8 to 2.7 per 100 000 population (P < .01). Self-payers were more likely to undergo LAGB (relative risk [RR]: 3.51 [95% confidence interval: 2.11–5.32]) and less likely to undergo LRYGB (RR: 0.45 [95% confidence interval: 0.33–0.58]) compared with privately insured adolescents. The rate of major in-hospital complication was 1%, and no deaths were reported. Of the patients who received LAGB, 4.7% had band revision/removal. In contrast, 2.9% of those who received LRYGB required reoperations. CONCLUSIONS: White adolescent girls disproportionately underwent bariatric surgery. Although LAGB has not been approved by the US Food and Drug Administration for use in children, its use has increased dramatically. There was a complication rate and no deaths. Long-term studies are needed to fully assess the efficacy, safety, and health care costs of these procedures in adolescents.

Surrogate obesity negatively impacts pregnancy rates in third-party reproduction

In a retrospective cohort review of third-party reproduction, we observed that surrogate body mass index (BMI) negatively impacts implantation rates in oocyte-donor in vitro fertilization cycles. A BMI > or =35 kg/m(2) cutoff is associated with a statistically significant decrease in pregnancy rates but not miscarriage rates.

Noninvasive in Situ Evaluation of Osteogenic Differentiation by Time-Resolved Laser-Induced Fluorescence Spectroscopy

The clinical implantation of bioengineered tissues requires an in situ nondestructive evaluation of the quality of tissue constructs developed in vitro before transplantation. Time-resolved laser-induced fluorescence spectroscopy (TR-LIFS) is demonstrated here to noninvasively monitor the formation of osteogenic extracellular matrix (ECM) produced by putative stem cells (PLA cells) derived from human adipose tissue. We show that this optical spectroscopy technique can assess the relative expression of collagens (types I, III, IV, and V) within newly forming osteogenic ECM. The results are consistent with those obtained by conventional histochemical techniques (immunofluorescence and Western blot) and demonstrate that TR-LIFS is a potential tool for monitoring the expression of distinct collagen types and the formation of collagen cross-links in intact tissue constructs.

Outcomes of bariatric surgery in adolescents.

Purpose of review The review summarizes the recent studies of bariatric surgery outcomes in adolescents. Recent findings Randomized prospective studies demonstrate superior weight loss, resolution of comorbidities, and improvement in quality of life in morbidly obese adolescents undergoing bariatric surgery vs. lifestyle changes alone. The enthusiasm for laparoscopic adjustable banding (LAGB) has been tempered by high reoperation rates. Laparoscopic sleeve gastrectomy (LSG) is a promising procedure for adolescents because it avoids intestinal bypass and implantation of a foreign body; recent data from adult series demonstrate mid-term results comparable with laparoscopic roux-en-y gastric bypass (LRYGB) with an improved safety profile. Summary Bariatric surgery is superior to lifestyle changes alone in treating adolescent morbid obesity. LRYGB remains the gold-standard operation for both adolescents and adults. Although LAGB and LSG are appealing because they avoid intestinal bypass, long-term studies are needed to fully evaluate their efficacy and safety in the adolescent population.

Risk factors for morbidity and mortality in pediatric patients with peritoneal dialysis catheters

PURPOSE As peritoneal dialysis (PD) is the preferred long-term dialysis modality in the pediatric population, we sought to identify risk factors for mortality and reoperation. METHODS A retrospective review of patients undergoing PD catheter insertions at a single center from 1994-2009 was performed. The following variables were evaluated: age (<1 year), comorbidities, omentectomy, concomitant gastrostomy, and laparoscopic technique. Multivariable Cox regressions analyses were used to evaluate patient survival and reoperation-free survival of PD catheters. RESULTS 207 patients with a median age of 10 years underwent PD insertion. Mortality was 7% with a median follow up of 72 months. Reoperation for malfunction and infection was required in 49% of patients with a median PD catheter survival of 11 months. Reoperation for hernias occurred in 14% of patients. Multivariate Cox regressions analyses identified age <1 year, lack of omentectomy, concomitant gastrostomy, and prematurity as variables significantly associated with higher rates of mortality or reoperation. CONCLUSIONS In this large study of pediatric patients undergoing PD, higher complication rates were noted in infants less than one year of age. Concomitant gastrostomy was associated with a higher rate of reoperation for infection. Failure to perform omentectomy was associated with a higher rate of catheter failure.

The Global Paediatric Surgery Network: A Model of Subspecialty Collaboration Within Global Surgery

Attention to surgical conditions in lowand middle-income countries (LMICs) has increased in recent years. Because half of the population in the world’s poorest countries are children [1], paediatric surgical conditions compose a significant proportion of the global burden of disease (BoD), and there are critical shortages in workforce and skills to treat these diseases in LMICs. Several populationbased studies have highlighted the magnitude of the need for paediatric surgery and the limited capacity, both in human resources and in infrastructure, to tackle the problem [2, 3]. Africa, in particular, has a grave shortage of paediatric surgeons. The number of fully trained paediatric surgeons ranges from 1 in Malawi (population 13 million) to 120 in Egypt (population of 80 million). In more than

Antibiotics-First Versus Surgery for Appendicitis: A US Pilot Randomized Controlled Trial Allowing Outpatient Antibiotic Management

Study objective Randomized trials suggest that nonoperative treatment of uncomplicated appendicitis with antibiotics‐first is safe. No trial has evaluated outpatient treatment and no US randomized trial has been conducted, to our knowledge. This pilot study assessed feasibility of a multicenter US study comparing antibiotics‐first, including outpatient management, with appendectomy. Methods Patients aged 5 years or older with uncomplicated appendicitis at 1 US hospital were randomized to appendectomy or intravenous ertapenem greater than or equal to 48 hours and oral cefdinir and metronidazole. Stable antibiotics‐first‐treated participants older than 13 years could be discharged after greater than or equal to 6‐hour emergency department (ED) observation with next‐day follow‐up. Outcomes included 1‐month major complication rate (primary) and hospital duration, pain, disability, quality of life, and hospital charges, and antibiotics‐first appendectomy rate. Results Of 48 eligible patients, 30 (62.5%) consented, of whom 16 (53.3%) were randomized to antibiotics‐first and 14 (46.7%) to appendectomy. Median age was 33 years (range 9 to 73 years), median WBC count was 15,000/&mgr;L (range 6,200 to 23,100/&mgr;L), and median computed tomography appendiceal diameter was 10 mm (range 7 to 18 mm). Of 15 antibiotic‐treated adults, 14 (93.3%) were discharged from the ED and all had symptom resolution. At 1 month, major complications occurred in 2 appendectomy participants (14.3%; 95% confidence interval [CI] 1.8% to 42.8%) and 1 antibiotics‐first participant (6.3%; 95% CI 0.2% to 30.2%). Antibiotics‐first participants had less total hospital time than appendectomy participants, 16.2 versus 42.1 hours, respectively. Antibiotics‐first‐treated participants had less pain and disability. During median 12‐month follow‐up, 2 of 15 antibiotics‐first‐treated participants (13.3%; 95% CI 3.7% to 37.9%) developed appendicitis and 1 was treated successfully with antibiotics; 1 had appendectomy. No more major complications occurred in either group. Conclusion A multicenter US trial comparing antibiotics‐first to appendectomy, including outpatient management, is feasible to evaluate efficacy and safety.

Multi-institutional practice patterns and outcomes in uncomplicated gastroschisis: A report from the University of California Fetal Consortium (UCfC)

BACKGROUND/PURPOSE Gastroschisis is a resource-intensive birth defect without consensus regarding optimal surgical and medical management. We sought to determine best-practice guidelines by examining differences in multi-institutional practices and outcomes. METHODS Site-specific practice patterns were queried, and infant-maternal chart review was retrospectively performed for gastroschisis infants treated at 5 UCfC institutions (2007-2012). The primary outcome was length of stay. Univariate analysis was done to assess variation practices and outcomes by site. Multivariate models were constructed with site as an instrumental variable and with sites grouped by silo practice pattern adjusting for confounding factors. RESULTS Of 191 gastroschisis infants, 164 infants were uncomplicated. Among uncomplicated patients, there were no deaths and only one case of necrotizing enterocolitis. Bivariate analysis revealed significant differences in practices and outcomes by site. Despite wide variations in practice patterns, there were no major differences in outcome among sites or by silo practice, after adjusting for confounding factors. CONCLUSIONS Wide variability exists in institutional practice patterns for infants with gastroschisis, but poor outcomes were not associated with expeditious silo or primary closure, avoidance of routine paralysis, or limited central line and antibiotic durations. Development of clinical pathways incorporating these practices may help standardize care and reduce health care costs.

Robotic extirpation of complex massive esophageal leiomyoma.

Esophageal leiomyomas are the most common benign mesenchymal esophageal tumors, but they occur rarely in the pediatric population. Leiomyomas are conventionally treated with extramucosal enucleation via an open thoracotomy. In this paper, we report a case of a complex massive retrocardiac esophageal leiomyoma that was successfully extirpated by using a robotic-assisted thoracoscopic technique. Intraoperative esophagoscopy and transillumination were useful adjuncts in identifying the esophagus and developing a safe extramucosal dissection plane.