Laparoscopic resection for gastrointestinal stromal tumors in the stomach

Purpose

Gastrointestinal stromal tumors (GISTs) should be surgically resected, even those smaller than 5?cm in size, which is the threshold of clinical malignancy for submucosal tumors (SMTs) in the gastrointestinal tract. This study reviewed the use of laparoscopic surgery for gastric partial resection of GISTs or SMTs that were suspected to be GISTs.

Methods

Eighteen patients underwent laparoscopic partial resection of the stomach for GISTs or SMTs. The tumor location was confirmed by intraluminal endoscopy. One-half of the circumference around the tumor was dissected, and the tumor was turned toward the abdominal cavity. The nonresected part of the tumor and the edge of the incision line was lifted up using forceps, and the incision line was closed using laparoscopic stapling devices.

Results

Two cases were diagnosed as GIST by endoscopic biopsy. Six patients underwent endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) examinations, which diagnosed five GISTs. There were 18 tumors smaller than 5?cm, including 10 GISTs, 4 leiomyomas, 3 schwannomas, and one heterotopic pancreas.

Conclusions

Endoscopic ultrasound-guided FNAB is recommended for definite preoperative diagnosis of histopathologically unknown SMTs to determine the indications for surgery. The laparoscopic approach with the assistance of endoscopy is useful for improving the curability, with minimal invasiveness for the partial resection of GISTs.     

Totally laparoscopic colectomy with intracorporeal anastomosis achieved using a laparoscopic linear stapler: experience of a single institute

Purpose  

Laparoscopic colonic surgery is now widely accepted. We assessed the safety and effectiveness of using a total intracorporeal surgical strategy to perform intracorporeal functional end-to-end anastomosis with an endoscopic linear stapler to treat colon cancer.     

Assessment of neuromuscular block at the orbicularis oris, corrugator supercilii, and adductor pollicis muscles

Purpose  

We studied neuromuscular block at the orbicularis oris, corrugator supercilii, and adductor pollicis muscles in anesthetized patients.     

Skeletal Analysis of the Long Bone Abnormality (lbab/lbab) Mouse, A Novel Chondrodysplastic C-Type Natriuretic Peptide Mutant

Long bone abnormality (lbab/lbab) is a strain of dwarf mice. Recent studies revealed that the phenotype is caused by a spontaneous mutation in the Nppc gene, which encodes mouse C-type natriuretic peptide (CNP). In this study, we analyzed the chondrodysplastic skeletal phenotype of lbab/lbab mice. At birth, lbab/lbab mice are only slightly shorter than their wild-type littermates. Nevertheless, lbab/lbab mice do not undergo a growth spurt, and their final body and bone lengths are only ~60% of those of wild-type mice. Histological analysis revealed that the growth plate in lbab/lbab mice, especially the hypertrophic chondrocyte layer, was significantly thinner than in wild-type mice. Overexpression of CNP in the cartilage of lbab/lbab mice restored their thinned growth plate, followed by the complete rescue of their impaired endochondral bone growth. Furthermore, the bone volume in lbab/lbab mouse was severely decreased and was recovered by CNP overexpression. On the other hand, the thickness of the growth plate of lbab/+ mice was not different from that of wild-type mice; accordingly, impaired endochondral bone growth was not observed in lbab/+ mice. In organ culture experiments, tibial explants from fetal lbab/lbab mice were significantly shorter than those from lbab/+ mice and elongated by addition of 10⁻⁷ M CNP to the same extent as lbab/+ tibiae treated with the same dose of CNP. These results demonstrate that lbab/lbab is a novel mouse model of chondrodysplasia caused by insufficient CNP action on endochondral ossification.     

Mechanical stretch down-regulates expression of the Smad6 gene in cultured rat mesangial cells

Background

Glomerular hypertension aggravates glomerular sclerosis by inducing growth factors, e.g., transforming growth factor-β (TGF-β) to mesangial matrix expansion. Smads are intracellular proteins that transmit signals from TGF-β to nucleus, and Smads are also negatively regulated by inhibitory Smads (I-Smads), Smad6 and Smad7. However, little is known about the role of I-Smads in glomerular hypertension. We studied I-Smad expression in cultured mesangial cells subjected to mechanical stretch as an in vitro model of glomerular hypertension.

Methods

Rat mesangial cells were cultured under cyclic mechanical stretch conditions using the Flexercell Strain Unit. Phosphorylated Smad1 and Smad2 were determined by Western blots. The expression of Smad6 and Smad7 mRNAs was determined by Northern blots. Stretch-mediated I-Smad mRNAs of cells pre-treated with MAPK-ERK kinase inhibitor, U0126, were also determined. Localization of phospho-Smad1, Smad6 and Smad7 proteins in the glomerulus of Dahl salt-sensitive rats was determined by immunohistochemistry.

Results

Stretch stress increased phospho-Smad1 levels, and significantly decreased Smad6 mRNA to 32?% of control, and increased Smad7 mRNA to 136?% of control. U0126 significantly attenuated stretch-mediated decreases in Smad6 mRNA, but had no effect on stretch-mediated increases in Smad7 mRNA. Phospho-Smad1, Smad6 and Smad7 proteins were localized in podocytes and mesangial cells of Dahl rats.

Conclusion

Mechanical stretch increases phospho-Smad1 levels and down-regulates Smad6 mRNA expression in mesangial cells. Stretch-mediated down-regulation of Smad6 is partially involved in ERK1/2 activation. These results indicate that glomerular hypertension might augment Smad1 signaling with concomitant attenuation of Smad6-mediated negative feedback.     

Role of Intraoperative Cholangiography in Patients Whose Biliary Tree Was Evaluated Preoperatively by Magnetic Resonance Cholangiopancreatography

Background

Routine performance of intraoperative cholangiography (IOC) during cholecystectomy is controversial. The aim of this study was to evaluate the role of IOC during cholecystectomy in addition to preoperative magnetic resonance cholangiopancreatography (MRCP) in our institution over a 12-year period.

Methods

A total of 425 consecutive patients who underwent IOC during cholecystectomy were included in this study. MRCP was performed preoperatively for bile duct evaluation in all patients. When common bile duct (CBD) stones were detected, they were removed endoscopically before the operation. We estimated the results of IOC in terms of the success rate, the detection rate of anatomic abnormality of the biliary system, and the incidence of residual CBD stones.

Results

MRCP preoperatively identified 6 (1.4?%) patients with abnormal biliary systems and 56 with CBD stones, which were endoscopically removed. The success rate of IOC was 93.8?% (399/425). Abnormalities of the biliary system were detected in 12 patients (12/399, 3.0?%) and CBD stones in 8 (8/399, 2.0?%). Of the eight patients with stones, seven had been examined by endoscopy preoperatively and found to have CBD stones. The detection rate of bile duct stones in patients with preoperative endoscopic removal of CBD stones (7/56, 12.5?%) was significantly higher than those with CBD stones first detected during IOC (1/365, 0.3?%) (p?<?0.01). Moreover, no residual CBD stones were detected in patients who were operated on within fewer than 12?days from endoscopic treatment to the operation.

Conclusions

IOC is indicated even after preoperative sphincterotomy for CBD stones. In our study, it resulted in a 12.5?% incidence of persistent stones after sphincterotomy. IOC plays an additional role in detecting CBD stones and in revealing abnormalities of the biliary tree in patients whose biliary tree was preoperatively evaluated by MRCP.     

Results of unilateral adrenalectomy in subclinical Cushing's syndrome due to adrenocorticotropic hormone‐independent macronodular adrenal hyperplasia

Adrenocorticotropic hormone (ACTH)‐independent bilateral adrenocortical macronodular adrenocortical hyperplasia (AIMAH) is a rare cause of Cushing's syndrome (CS). Traditionally, bilateral adrenalectomy with subsequent lifetime steroid replacement has been considered to be the treatment of choice. In the present study, we evaluated the long‐term results of unilateral adrenalectomy in subclinical CS (SCS) due to AIMAH, with regard to the main laboratory and clinical abnormalities. Two patients with confirmed SCS due to AIMAH underwent unilateral laparoscopic adrenalectomy to reduce the cortisol‐secreting tissue. These procedures were successfully conducted in both cases without open conversion, and no surgery‐related morbidity occurred. In both cases, the size of the remaining adrenal gland appeared quite stable, and neither of the patients showed a Cushingoid appearance. Unilateral adrenalectomy achieved satisfactory and prolonged control of cortisol secretion, and also reduced the risk of metabolic disorders and cardiovascular disease after surgery. It can be a safe and effective treatment for SCS due to AIMAH, while maintaining the patient's quality of life.     

Effects of Sevoflurane and Isoflurane on Renal Function and on Possible Markers of Nephrotoxicity

Background: Low-flow sevoflurane anesthesia is associated with increasing circuit concentrations of compound A, which is nephrotoxic in rats, but the effect of compound A and low-flow sevoflurane anesthesia on renal function in humans is unclear. The authors compared the effects of high- and low-flow sevoflurane and isoflurane anesthesia on renal function and on several possible markers of nephrotoxicity in humans.

Methods: Forty-two patients without preexisting renal disease underwent either low-flow isoflurane (1 l/min, n = 14), low-flow sevoflurane (1 l/min, n = 14), or high-flow sevoflurane (6 l/min, n = 14) anesthesia for body-surface-area surgery scheduled to last at least 4 h. Twenty-four-hour urinary excretion of N-acetyl-[small beta, Greek]-glucosaminidase (NAG), [small beta, Greek]2-microglobulin, protein, glucose, blood urea nitrogen (BUN), and serum creatinine concentrations were measured before and after anesthesia.

Results: There were no differences in blood urea nitrogen, creatinine, and creatinine clearance among the three groups after anesthesia. Increased urinary N-acetyl-[small beta, Greek]-glucosaminidase excretions were seen in the low-flow and high-flow sevoflurane groups, but not in the low-flow isoflurane group (P < 0.01). Ten patients in the low-flow sevoflurane group had 24-h urinary excretion of protein that exceeded the normal ranges after anesthesia, but only one patient in the isoflurane and none in the high-flow sevoflurane groups had this.     

Microcirculation of kidney and skin during left ventricular assisted circulation--comparative studies of pulsatile and nonpulsatile assists]

We examined microcirculation of the kidney and skin over a six-hour period in an acute myocardial infarction model in pigs. The outflow cannula was placed in the ascending aorta, the inflow cannula was placed the in left atrium, and a pump was connected to each (pulsatile group, Zeon Medical pneumatic pump; nonpulsatile group, Nikkiso HPM-15). Items examined included the regional blood flow of the cortex and medulla in the kidney and skin, renal and carotid arterial flow, arterial ketone body ratio (AKBR), lactate/pyruvic acid (L/P), BUN, creatinine, and beta 2-microglobulin. After the experimental study, the major organs were removed and a pathological study was performed. The mean aortic pressure after the assist could be maintained at about 100 mmHg. There were no significant differences between the two groups in mean aortic pressure and total cardiac output. Under assisted circulation, the pulse pressure was maintained at about 15 mmHg in the nonpulsatile group and about 40 mmHg in the pulsatile group. After the assist, there were no significant differences in the carotid arterial blood flow between the two groups. However, there were significant differences between the two groups in the renal arterial, renal cortical, and regional skin blood flows. In the laboratory data, there were significant differences between the two groups in AKBR, L/P, and beta 2-microglobulin. Pathological findings on the kidney in the nonpulsatile group showed expansion of the proximal tubes, retention of red blood cells, and expansion of blood capillaries within the glomerulus. On the other hand, the pulsatile group showed almost normal formation. In the lungs, the nonpulsatile group showed edematous change in the air cells and the pulsatile group showed almost normal formation. The results of the previous and current study indicated that the pulsatile assist produced superior circulation in the kidney and peripheral organs and superior cellular metabolism in the early treatment of acute left cardiac failure. On the other hand, nonpulsatile assisted circulation was found to be ineffective in maintaining the circulation in the body, and to be potentially capable of causing irreversible damage of major organs if continuous for more than three hours. The results also indicated that pulsatility was necessary to maintain normal circulation in the peripheral organs and cellular metabolism in the early treatment of acute left cardiac failure.     

Japanese consensus guidelines for pediatric nuclear medicine

The Japanese Society of Nuclear Medicine has recently published the consensus guidelines for pediatric nuclear medicine. This article is the English version of the guidelines. Part 1 proposes the dose optimization in pediatric nuclear medicine studies. Part 2 comprehensively discusses imaging techniques for the appropriate conduct of pediatric nuclear medicine procedures, considering the characteristics of imaging in children.