Laparoscopic Versus Open Pyloromyotomy for Hypertrophic Pyloric Stenosis

PURPOSE: Hypertrophic pyloric stenosis (HPS) is a common condition affecting infants that causes severe projectile non-bilious vomiting in the first few months of life. Although open pyloromyotomy is the standard treatment for HPS, recently, the laparoscopic approach has rapidly been adopted by pediatric surgeons. The aim of this study is to determine the efficacy and safety of laparoscopic pyloromyotomy by comparing the clinical results of laparoscopic and open pyloromyotomy. METHODS: Between January 2007 and September 2012, a cohort of 69 children who underwent pyloromyotomy at Seoul National University Children's Hospital were followed; open pyloromyotomy (OP, n=56) and laparoscopic pyloromyotomy (LP, n=13). A retrospective analysis of patient's characteristics and clinical outcomes in patients with open or laparoscopic pyloromyotomy for HPS was performed. The evaluated characteristics included gestational age, sex, birth weight, age and weight at operation. Clinical outcomes included operation time, length of hospital stay, time to postoperative full feeds without vomiting, number of postoperative vomiting and complications. RESULTS: There were no significant differences in characteristics, length of hospital stay and time to postoperative full feeds without vomiting between the two groups. Incidence of postoperative vomiting in the LP group was significantly lower than that in the OP group (OP: 5.07+/-4.60 vs. LP: 2.00+/-2.16, p=0.035). In contrast, the operation time was longer, following the LP group (OP: 26.30+/-9.95 vs. LP: 44.15+/-19.56, p0.999) and wound problems (OP: 4 vs. LP 1, p>0.999) were found to be similar in both groups. CONCLUSION: Both open and laparoscopic pyloromyotomy are safe procedures for the management of hypertrophic pyloric stenosis. Incidence of vomiting was statistically superior in the laparoscopic group. In addition, postoperative complications were fewer in this group. However, an improvement in the operation time will be needed for the future development of laparoscopic pyloromyotomy.

Effects of Inositol 1,4,5-triphosphate on Osteoclast Differentiation in RANKL-induced Osteoclastogenesis

The receptor activator of NF-kappaB ligand (RANKL) signal is an activator of tumor necrosis factor receptor-associated factor 6 (TRAF6), which leads to the activation of NF-kappaB and other signal transduction pathways essential for osteoclastogenesis, such as Ca2+ signaling. However, the intracellular levels of inositol 1,4,5-trisphosphate (IP3) and IP3-mediated cellular function of RANKL during osteoclastogenesis are not known. In the present study, we determined the levels of IP3 and evaluated IP3-mediated osteoclast differentiation and osteoclast activity by RANKL treatment of mouse leukemic macrophage cells (RAW 264.7) and mouse bone marrow-derived monocyte/macrophage precursor cells (BMMs). During osteoclastogenesis, the expression levels of Ca2+ signaling proteins such as IP3 receptors (IP3Rs), plasma membrane Ca2+ ATPase, and sarco/endoplasmic reticulum Ca2+ ATPase type2 did not change by RANKL treatment for up to 6 days in both cell types. At 24 h after RANKL treatment, a higher steady-state level of IP3 was observed in RAW264.7 cells transfected with green fluorescent protein (GFP)-tagged pleckstrin homology (PH) domains of phospholipase C (PLC) delta, a probe specifically detecting intracellular IP3 levels. In BMMs, the inhibition of PLC with U73122 [a specific inhibitor of phospholipase C (PLC)] and of IP3Rs with 2-aminoethoxydiphenyl borate (2APB; a non-specific inhibitor of IP3Rs) inhibited the generation of RANKL-induced multinucleated cells and decreased the bone-resorption rate in dentin slice, respectively. These results suggest that intracellular IP3 levels and the IP3-mediated signaling pathway play an important role in RANKL-induced osteoclastogenesis.

Laparoscopic Versus Open Appendectomy for Simple and Perforated Appendicitis in Children / 대한내시경복강경외과학회지

PURPOSE: Laparoscopic appendectomy is a popular surgical treatment of choice for children with appendicitis. This study compared laparoscopic appendectomy (LA) with an open appendectomy (OA) in children with simple appendicitis (SA) and perforated appendicitis (PA) to confirm the safety and effectiveness of the laparoscopic procedure. METHODS: A retrospective medical record review was performed on 193 patients who underwent an appendectomy at our institution from January, 2008 to August, 2011. The demographic properties and postoperative factors including complications were assessed. RESULTS: Among 140 SA, there were 81 and 59 cases of OA and LA, respectively. In SA, the time to bowel movement in LA was shorter than OA (0.9 vs. 1.2 days, p=0.0005) and the number of times analgesics were used in LA were significantly lower than OA (1.8 vs. 2.5, p=0.027). Of 53 PA, 30 cases received OA whereas 23 cases underwent LA. In patients with PA, the LA group were older (124.0 vs. 98.8 months, p=0.027) with a longer operative time (93.5 vs. 68.2 minutes, p=0.02). On the other hand, the time to diet was faster in LA (1.8 vs. 3.2 days, p=0.02). In both SA and PA, there were no significant differences between OA and LA with respect to gender, hospital stay, drain insertion, duration of antibiotics usage, and complications. In SA, the LA group had fewer complications than the OA group with borderline significance. CONCLUSION: LA is a safe and effective way to treat SA and PA in children.

Alteration of Expression of Ca(2+) Signaling Proteins and Adaptation of Ca(2+) Signaling in SERCA2(+/-) Mouse Parotid Acini

PURPOSE: The sarco/endoplasmic reticulum Ca(2+)-ATPase (SERCA), encoded by ATP2A2, is an essential component for G-protein coupled receptor (GPCR)-dependent Ca(2+) signaling. However, whether the changes in Ca(2+) signaling and Ca(2+) signaling proteins in parotid acinar cells are affected by a partial loss of SERCA2 are not known. MATERIALS AND METHODS: In SERCA2(+/-) mouse parotid gland acinar cells, Ca(2+) signaling, expression levels of Ca(2+) signaling proteins, and amylase secretion were investigated. RESULTS: SERCA2(+/-) mice showed decreased SERCA2 expression and an upregulation of the plasma membrane Ca(2+) ATPase. A partial loss of SERCA2 changed the expression level of 1, 4, 5-tris-inositolphosphate receptors (IP(3)Rs), but the localization and activities of IP3Rs were not altered. In SERCA2(+/-) mice, muscarinic stimulation resulted in greater amylase release, and the expression of synaptotagmin was increased compared to wild type mice. CONCLUSION: These results suggest that a partial loss of SERCA2 affects the expression and activity of Ca(2+) signaling proteins in the parotid gland acini, however, overall Ca(2+) signaling is unchanged.

Initiation Site of Ca2+ Entry Evoked by Endoplasmic Reticulum Ca2+ Depletion in Mouse Parotid and Pancreatic Acinar Cells

PURPOSE: In non-excitable cells, which include parotid and pancreatic acinar cells, Ca(2+) entry is triggered via a mechanism known as capacitative Ca(2+) entry, or store-operated Ca(2+) entry. This process is initiated by the perception of the filling state of endoplasmic reticulum (ER) and the depletion of internal Ca(2+) stores, which acts as an important factor triggering Ca(2+) entry. However, both the mechanism of store-mediated Ca(2+) entry and the molecular identity of store-operated Ca(2+) channel (SOCC) remain uncertain. MATERIALS AND METHODS: In the present study we investigated the Ca(2+) entry initiation site evoked by depletion of ER to identify the localization of SOCC in mouse parotid and pancreatic acinar cells with microfluorometeric imaging system. RESULTS: Treatment with thapsigargin (Tg), an inhibitor of sarco/endoplasmic reticulum Ca(2+)-ATPase, in an extracellular Ca(2+) free state, and subsequent exposure to a high external calcium state evoked Ca(2+) entry, while treatment with lanthanum, a non-specific blocker of plasma Ca(2+) channel, completely blocked Tg-induced Ca(2+) entry. Microfluorometric imaging showed that Tg-induced Ca(2+) entry started at a basal membrane, not a apical membrane. CONCLUSION: These results suggest that Ca2+ entry by depletion of the ER initiates at the basal pole in polarized exocrine cells and may help to characterize the nature of SOCC.

Expression of Ca2+-dependent Synaptotagmin Isoforms in Mouse and Rat Parotid Acinar Cells

Synaptotagmin is a Ca2+ sensing protein, which triggers a fusion of synaptic vesicles in neuronal transmission. Little is known regarding the expression of Ca2+ - dependent synaptotagmin isoforms and their contribution to the release of secretory vesicles in mouse and rat parotid acinar cells. We investigated a type of Ca2+ - dependent synaptotagmin and Ca2+ signaling in both rat and mouse parotid acinar cells using RT-PCR, microfluorometry, and amylase assay. Mouse parotid acinar cells exhibited much more sensitive amylase release in response to muscarinic stimulation than did rat parotid acinar cells. However, transient [Ca2+]i increases and Ca2+ influx in response to muscarinic stimulation in both cells were identical, suggesting that the expression or activity of the Ca2+ sensing proteins is different. Seven Ca2+ - dependent synaptotagmins, from 1 to 7, were expressed in the mouse parotid acinar cells. However, in the rat parotid acinar cells, only synaptotagmins 1, 3, 4 and 7 were expressed. These results indicate that the expression of Ca2+ - dependent synaptotagmins may contribute to the release of secretory vesicles in parotid acinar cells.

Assessment of Attenuation Correction Techniques with a 137Cs Point Source / 대한핵의학회잡지

PURPOSE: The objective of this study was to assess attenuation correction algorithms with the 137Cs point source for the brain positron emission tomography (PET) imaging process. MATERIALS AND METHODS: Four different types of phantoms were used in this study for testing various types of the attenuation correction techniques. Transmission data of a 137Cs point source were acquired after infusing the emission source into phantoms and then the emission data were subsequently acquired in 3D acquisition mode. Scatter corrections were performed with a background tail-fitting algorithm. Emission data were then reconstructed using iterative reconstruction method with a measured (MAC), elliptical (ELAC), segmented (SAC) and remapping (RAC) attenuation correction, respectively. Reconstructed images were then both qualitatively and quantitatively assessed. In addition, reconstructed images of a normal subject were assessed by nuclear medicine physicians. Subtracted images were also compared. RESULTS: ELAC, SAC, and RAC provided a uniform phantom image with less noise for a cylindrical phantom. In contrast, a decrease in intensity at the central portion of the attenuation map was noticed at the result of the MAC. Reconstructed images of Jaszack and Hoffan phantoms presented better quality with RAC and SAC. The attenuation of a skull on images of the normal subject was clearly noticed and the attenuation correction without considering the attenuation of the skull resulted in artificial defects on images of the brain. CONCLUSION: the complicated and improved attenuation correction methods were needed to obtain the better accuracy of the quantitative brain PET images.

Improved Scatter Correction for SPECT Images: A Monte Carlo Simulation Study / 대한핵의학회잡지

PURPOSE: Abutted scatter energy windows used for a triple energy window (TEW) method may provide wrong estimation of scatter. This study is to propose an extended TEW (ETEW) method, which doesn't require abutted scatter energy windows and overcomes the shortcomings of TEW method. MATERIALS AND METHODS: The ETEW is a modification of the TEW which corrects for scatter by using abutted scatter rejection windows, which can overestimate or underestimate scatter. The ETEW is compared to the TEW using Monte Carlo simulated data for point sources as well as hot and cold spheres in a cylindrical water phantom. Various main energy window widths (10 %, 15 % and 20 %) were simulated. Both TEW and ETEW improved image contrast, % recovery coefficients and normalized standard deviation. RESULTS: Both of TEW and ETEW improved image contrast and % recovery coefficients. Estimated scatter components by the TEW were not proportional to the true scatter components over the main energy windows when ones of 10 %, 15 %, and 20 % were simulated. The ETEW linearly estimated scatter components over the width of the main energy windows. CONCLUSION: We extended the TEW method into the method which could linearly estimate scatter components over the main energy windows.