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ABSTRACT: There might be discordance between inter-lobar borders of the main portal fissure (MPF) using the middle hepatic vein (MHV) and of the portal segmentation. Forty-five living donors who underwent right hepatectomy for the adult recipients from 2007 to 2011 in a tertiary hospital were retrospectively analyzed. The donors were classified into conventional right hepatectomy along the MPF (cRL group, n = 26) and modified right hepatectomy along right-side shifted transection plane from the MPF (mRL group, n = 19). The cRL donors had higher postoperative peak level of INR (1.84 vs. 1.62; P = 0.022), and bilirubin (3.37 mg/dl vs. 2.74 mg/dl; P = 0.065) than the mRL donors. cRL donors experienced greater depression of platelet count (144 per nL vs. 168 per nL; P = 0.042) and enlargement of splenic volume (52% vs. 37%; P = 0.025) than mRL donors for 7 days after hepatectomy. The regeneration of the left lateral sector was more accelerated in the cRL donors than the mRL donors for postoperative 3 months (148% vs. 84%; P = 0.015). There were no differences in the post-transplant graft function, incidence of complications, and graft survival rates between the two groups of recipients (P > 0.05). This study suggests that the conventional right hepatectomy along the MHV might increase donor risk by reducing parenchymal liver volume of the segment IV.
Transplant International 07/2012; 25(10):1072-83. · 2.92 Impact Factor
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ABSTRACT: We determined the influence of bile spillage on recurrence and survival during laparoscopic cholecystectomy (LC) for gallbladder (GB) cancer. Among the 136 patients with GB cancer treated at Ajou University Hospital between 1994 and 2007, 28 underwent LC alone. We compared patients without bile spillage (bile spillage [-] group, n = 16) with patients who had bile spillage (bile spillage [+] group, n = 12). There was no statistical difference in stage between the groups. In the bile spillage (-) group, all patients underwent curative resection and there were two patients with locoregional recurrences and three patients with systemic recurrences. In the bile spillage (+) group, five patients underwent R1 resection and one patient underwent R2 resection and all eight recurrent patients had systemic recurrences. The disease-free survival and overall survival were shorter in the bile spillage (+) group (disease-free survival, 71.4 vs 20.9 months; P = 0.028; overall survival, 72.6 vs 25.8 months; P = 0.014). Bile spillage is likely to be an association with an incomplete resection and systemic recurrences. When GB cancer is suspected during LC, conversion to open surgery for preventing bile spillage and achieving curative resection should be considered.
The American surgeon 06/2011; 77(6):697-701. · 1.28 Impact Factor
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ABSTRACT: To determine the feasibility of volumetric criteria without anatomic exclusion for the selection of right posterior sector (RPS) grafts for adult-to-adult living donor liver transplantation (LDLT), we reviewed and compared our transplant data for RPS grafts and right lobe (RL) grafts. Between January 2008 and September 2010, adult-to-adult LDLT was performed 65 times at our institute; 13 of the procedures (20%) were performed with RPS grafts [the posterior sector (PS) group], and 39 (60%) were performed with RL grafts (the RL group). The volumetry of the 13 RPS donor livers showed that the RPS volume was 39.8% ± 7.6% of the total liver volume. Ten of the 13 donors had to donate RPS grafts because the left liver volume was inadequate. All donor procedures were performed successfully, and all donors recovered from hepatectomy. However, longer operative times were required for the procurement of RPS grafts versus RL grafts (418 ± 40 versus 345 ± 48 minutes, P < 0.001). The postoperative recovery of liver function was smoother for the donors of the PS group versus the donors of the RL group. The RPS grafts had significantly smaller hepatic artery and bile duct openings than the RL grafts. All recipients with RPS grafts survived LDLT. No recipients experienced vascular graft complications or small-for-size graft dysfunction. There were no significant differences in the incidence of posttransplant complications between the donors and recipients of the PS and RL groups. The 3-year graft survival rates were favorable in both groups (100% in the PS group versus 91% in the RL group). In conclusion, the selection of RPS grafts by volume criteria is a feasible strategy for an adult-to-adult LDLT program.
Liver Transplantation 05/2011; 17(9):1046-58. · 3.39 Impact Factor
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ABSTRACT: Aerobic lactate production of which the final step is executed by lactate dehydrogenase (LDH) is one of the typical phenotypes in invasive tumor development. However, detailed mechanism of how LDH links to cancer cell invasiveness remains unclear. This study shows that suppressed LDHB expression plays a critical role in hepatoma cell invasiveness by inducing claudin-1 (Cln-1), a tight junction protein, via mitochondrial respiratory defects. First, we found that all the SNU human hepatoma cells with increased glycolytic lactate production have the defective mitochondrial respiratory activity and the Cln-1-mediated high invasive activity. Similar results were also obtained with human hepatocellular carcinoma tissues. Unexpectedly, the increased lactate production was due to LDH isozyme shifts to LDH5 by LDHB down-expression rather than LDHA induction, implying the importance of LDHB modulation. Second, LDHB knockdown did not only trigger Cln-1 induction at the transcriptional level, but also induced respiratory impairment. Interestingly, most respiratory inhibitors except KCN induced Cln-1 expression although complex I inhibition by rotenone was most effective on Cln-1 induction. Respiratory defect-mediated Cln-1 induction was further confirmed by knockdown of NDUFA9, one of complex I subunits. Finally, ectopic expression of LDHB attenuated the invasiveness of both SNU 354 and 449 cells whereas LDHB knockdown significantly augmented the invasiveness of Chang cells with Cln-1induction. The increased invasive activity by LDHB modulation was clearly reversed by knocking-down Cln-1. Taken together, our results suggest that LDHB suppression plays an important role in triggering or maintaining the mitochondrial defects and then contributes to cancer cell invasiveness by inducing Cln-1 protein.
Experimental Cell Research 02/2011; 317(8):1108-18. · 3.58 Impact Factor
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ABSTRACT: This recipient with situs inversus totalis (SIT) was a 60-year-old female who had hepatitis B-related end-stage liver disease. Preoperative donor evaluation showed that the right posterior section satisfied graft volume and was space-fitting in the recipient hepatic fossa when it was rotated 180 degrees. The operation and postoperative course progressed satisfactorily. Three weeks after living donor liver transplantation (LDLT), the graft function was disturbed by compression of bottom-placed right hepatic vein. This was treated with a vascular stent and subsequently the graft function was normalized. The present case shows that LDLT for patients with SIT using a right posterior section graft is feasible.
World Journal of Gastroenterology 05/2010; 16(18):2311-3. · 2.47 Impact Factor
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ABSTRACT: A functional and biochemical interaction of TIS21(/BTG2/PC3) with Forkhead box M1 (FoxM1), essential transcription factor for hepatocyte regeneration and a master regulator of mitotic gene expression, was explored. Growth of hepatocellular carcinoma (HCC), developed by a single injection of diethylnitrosamine (DEN), was the same in both the TIS21(+/+) and TIS21(-/-) mice until 6 months, whereas it was significantly higher in the TIS21(-/-) mice at 9 months. Expression of TIS21 was significantly lower in both human and murine HCCs than in the surrounding tissues. Forced expression of TIS21 impaired growth, proliferation, and tumorigenic potential of Huh7 cells. At the mechanistic level, TIS21 inhibited FoxM1 phosphorylation, a required modification for its activation, by reducing cyclin B1-cdk1 activity, examined by in vitro kinase assay and FoxM1 mutant analyses. These observations were further confirmed in vivo by the reciprocal control of TIS21 expression and FoxM1 phosphorylation in the diethylnitrosamine-induced HCCs and TIS21(-/-) mouse embryonic fibroblast (MEF), in addition to increased expression of cyclin B1 and cdk1 activity. CONCLUSION: TIS21 negatively regulated hepatocarcinogenesis in part by disruption of the FoxM1-cyclin B1 regulatory loop, thereby inhibiting proliferation of transformed cells developed in mouse and human livers.
Hepatology 06/2008; 47(5):1533-43. · 11.66 Impact Factor
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Surgery 07/2007; 141(6):832-4. · 3.10 Impact Factor
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ABSTRACT: To evaluate the efficacy of hilar duct oriented hepatectomy for intractable hepatolithiasis, the ventral hilum exposure (VHE) method that has been applied by the authors.
From June 1994 to June 2004 for a period of 10 years, 153 patients who had Tsunoda type III or IV hepatolithiasis, received hepatectomy at our institution. Among these patients, 128 who underwent hepatectomy by the VHE method were the subjects for the study. We analyzed the risk of this procedure, residual rate of intra-hepatic stones, and stone recurrent rates.
The average age was 54.2 years, and the male to female ratio was 1:1.7. The average follow-up period was 25.6 mo (6-114 mo). There was no post-operative severe complication or mortality after the operation. The rate of residual stones was 5.4% and the rate of recurrent stones was 4.2%.
VHE is a safe surgical procedure and provides favorable treatment results of intractable hepatolithiasis. Especially, this procedure has advantage in that intra-hepatic bile duct stricture may be confirmed and corrected directly during surgery.
World Journal of Gastroenterology 02/2006; 12(3):431-6. · 2.47 Impact Factor
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ABSTRACT: To investigate the clinicopathological risk factors for immediate post-operative fatal recurrence of hepatocellular carcinoma (HCC), which may have practical implication and contribute to establishing high risk patients for pre- or post-operative preventive measures against HCC recurrence.
From June 1994 to May 2004, 269 patients who received curative resection for HCC were reviewed. Of these patients, those who demonstrated diffuse intra-hepatic or multiple systemic recurrent lesions within 6 mo after surgery were investigated (fatal recurrence group). The remaining patients were designated as the control group, and the two groups were compared for clinicopathologic risk factors.
Among the 269 patients reviewed, 30 patients were enrolled in the fatal recurrence group. Among the latter, 20 patients showed diffuse intra-hepatic recurrence type and 10 showed multiple systemic recurrence type. Multivariate analysis between the fatal recurrence group and control group showed that pre-operative serum alpha-fetoprotein (AFP) level was greater than 1,000 microg/L (P = 0.02; odds ratio = 2.98), tumor size greater than 6.5 cm (P = 0.03; OR = 2.98), and presence of microvascular invasion (P = 0.01; OR = 4.89) were the risk factors in the fatal recurrence group. The 48.1% of the patients who had all the three risk factors and the 22% of those who had two risk factors experienced fatal recurrence within 6 mo after surgery.
Three distinct risk factors for immediate post-operative fatal recurrence of HCC after curative resection are pre-operative serum AFP level > 1,000 microg/L, tumor size > 6.5 cm, and microvascular invasion. The high risk patients with two or more risk factors should be the candidates for various adjuvant clinical trials.
World Journal of Gastroenterology 01/2006; 12(1):99-104. · 2.47 Impact Factor
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ABSTRACT: Hemangiopericytoma is a rare tumor especially when it rises in the peritoneal cavity. We present a case of a 60-year-old woman with an isolated recurrent hemangiopericytoma of the liver. The patient presented with a palpable right upper quadrant abdominal mass, which occurred 7 years after undergoing resection of a malignant hemangiopericytoma arising from the greater omentum. She had not followed up 6 mo after surgery. Various imaging studies showed a single large, well-capsulated liver tumor with central necrosis, accompanied by hypervascularity typical of a vascular tumor. Preoperative laboratory HBsAg and anti-HCV workup were both negative. Under the impression of recurrent malignant hemangiopericytoma, right trisegmentectomy was performed to completely resect the tumor. Pathological examination confirmed the diagnosis of recurrent hemangiopericytoma. Even though the incidence of the hemangiopericytoma is relatively low, malignant hemangiopericytoma has a tendency to recur frequently after a long-term disease-free interval. Also, the recurrent hemangiopericytoma is not easily detected early during follow-up until it becomes symptomatic because there are no specific tumor markers, and because of the diversity with regard to site of recurrence. The authors suggest that Positron Emission Tomogram (PET) may be a useful tool for the detection of recurrent hemangiopericytoma. We describe herein some characteristics and behaviors of malignant hemangiopericytoma, particularly after surgical resection.
World Journal of Gastroenterology 08/2005; 11(27):4281-4. · 2.47 Impact Factor
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In-Ho Jeong,
Yong-Sik Jung,
Hong Kim, Bong-Wan Kim,
Jung-Woon Kim,
Jeong Hong,
Hee-Jung Wang,
Myung-Wook Kim,
Byung-Moo Yoo,
Jin-Hong Kim,
Jae-Ho Han,
Wook-Hwan Kim
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ABSTRACT: To investigate the relationship between pancreatic amylase in bile duct and the clinico-pathological features in adult patients with choledochal cyst and anomalous pancreatico-biliary ductal union (APBDU).
From 39 patients who underwent surgery for choledochal cyst between March 1995 and March 2003, we selected 15 adult patients who had some symptoms and were radiologically diagnosed as APBDU, and their clinico-pathological features were subsequently evaluated retrospectively. However, we could not obtain biliary amylase in all the patients because of the surgeon's slip. Therefore, we measured the amylase level in gall bladder of 10 patients and in common bile duct of 11 patients.
Levels of amylase in common bile duct and gall bladder ranged from 11,500 to 212,000 IU/L, and the younger the patients, the higher the biliary amylase level (r = -0.982, P<0.01). Pathologically, significant correlation was found between the size of choledochal cyst and the grade of inflammation (r = 0.798, P<0.01). And, significant correlation was found between the level of amylase in gall bladder and the grade of hyperplasia. On the other hand, there was no correlation to the age of symptomatic onset or inflammatory grade (r = 0.743, P<0.05). Level of lipase was elevated from 6,000 to 159,000 IU/L in bile duct and from 14,400 to 117,000 IU/L in the gall bladder; however, there was no significant correlation with age or clinico-pathological features.
The results support the notion that amylase has a particular role in the onset of symptoms, and suggest that a large amount of biliary amylase induces early onset of symptom, thereby making early diagnosis possible.
World Journal of Gastroenterology 04/2005; 11(13):1965-70. · 2.47 Impact Factor
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Je Hwan Won,
Jong Doo Lee,
Hee Jung Wang,
Gui-Eon Kim, Bong Wan Kim,
Hyunee Yim,
Sang Keon Han,
Chan H Park,
Chul Woo Joh,
Kyung-Hwa Kim,
Kyung Bae Park,
Kyong-Min Shin
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ABSTRACT: A specially designed self-expandable covered metallic stent impregnated with the beta-emitting radioisotope 166Ho (166Ho, energy: 1.85 and 1.76 MeV, T12: 26.8 h) was developed at our institute for the purpose of intraluminal palliative brachytherapy, as well as for treating malignant esophageal stricture and swallowing difficulty. The aim of this study was to evaluate the tissue response to brachytherapy and the safety of the radioactive metallic stent with regard to the normal canine esophagus before clinical application.
166Ho was impregnated into the polyurethane membrane (50 micron thickness) covering the outer surface of a self-expandable metallic stent (diameter, 18 mm; length, 40 mm). Stents with radioactivity 4.0-7.8 mCi (Group A, n = 15), 1.0-1.8 mCi (Group B, n = 5), and 0.5-0.7 mCi (Group C, n = 5) were placed in the esophagi of 25 healthy beagle dogs, and the stents were tightly anchored surgically to prevent migration. The estimated radiation dose calculated by Monte Carlo simulation was 194-383 Gy in Group A, 48-90 Gy in Group B, and 23-32 Gy in Group C. The dogs were killed 8-12 weeks after insertion of the stents, and histologic examinations of the esophageal walls were performed.
In Group A, 3 of 15 dogs died of wound infection, so specimens were obtained from only 12 dogs; all 12 cases showed esophageal stricture with mucosal ulceration. Microscopically, severe fibrosis and degeneration of the muscular propria were found in 3 dogs, complete fibrosis of the entire esophageal wall was found in 7 dogs, and esophageal fibrosis with radiation damage within periesophageal soft tissue was found in 2 dogs. However, esophageal perforation did not develop, despite extremely high radiation doses. In Group B, glandular atrophy and submucosal fibrosis were found, but the muscular layer was intact. In Group C, no histologic change was found in 3 dogs, but submucosal inflammation and glandular atrophy with intact mucosa were found in 2 dogs.
A radioactive, self-expandable covered metallic stent can be used as an alternative therapeutic modality for the palliative treatment of malignant esophageal stricture.
International Journal of Radiation OncologyBiologyPhysics 08/2002; 53(4):1005-13. · 4.11 Impact Factor
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ABSTRACT: Most distributed shared memory systems use point-to-point networks
in conjunction with directory-based cache coherence protocols. A cache
invalidation transaction generates a number of unicast invalidation
messages and as many acknowledgment messages. This results in heavy
network traffic, high latency, and high occupancy at home nodes. This
paper introduces a fast cache invalidation method, called collective
cache invalidation (CCI), and its simple and cost effect implementation
method, called virtual bus based collective cache invalidation (VCCI).
The simulation results show that we can reduce the total network traffic
up to 45% and the overall execution time up to 11% by VCCI. The proposed
method keeps the system scalable-the growth rate of the implementation
cost if O(N√N), and, VCCI can reduce the complexity of coherence
protocol and make directory controllers simple since it does not require
acknowledgment messages
Parallel and Distributed Systems, 2000. Proceedings. Seventh International Conference on; 02/2000
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ABSTRACT: This paper presents a mesh with virtual buses as the
bandwidth-efficient implementation of the mesh with multiple
broadcasting on which many computational problems can be solved with
reduced time complexity. The new system provides a low latency and high
bandwidth communication mechanism without the disadvantage of the dual
network approach: the possible bandwidth waste. The virtual buses are
built using those communication links of the base point-to-point mesh
network only upon request. Even if bus requests are not made, the full
network bandwidth is harnessed by the point-to-point communication. On
the contrary, the bandwidth assigned to the conventional real buses will
be wasted when there is little bus request. This paper introduces a
wormhole router design equipped with the virtual bus functions,
describes the connections among these routers, and presents various
virtual bus transactions. We prove the effectiveness of the virtual bus
by showing that a representative semigroup computation can be solved
very efficiently on it: a vector maxima finding is accelerated by 2.66
times in the experiment. We also explore the network characteristics by
the distribution-driven simulation of the system. These evaluations
convinced us that the mesh with virtual buses is a promising approach to
low latency and high bandwidth communication which has applications in
many parallel computations such as in parallel simulations, computer
graphics, real time systems, and many others
Parallel Processing, 1999. Proceedings. 1999 International Conference on; 02/1999
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ABSTRACT: We perform model validation of a wormhole router system. Our
simulation model is calibrated through measurement of our real wormhole
router system. The average latency of real system output is in the 95%
confidence interval of our simulation model. This validated model can be
applied to the performance analysis of the large wormhole router system
with strong confidence
High Performance Computing on the Information Superhighway, 1997. HPC Asia '97;
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ABSTRACT: The exact role of postoperative radiotherapy following curative surgery of rectal carcinoma has been debated. In this retrospective study, we examined the effect of radiotherapy on the survival and recurrence rate of rectal cancer patients who underwent total mesorectal excision.
Since June 1994, stage II and III rectal cancer patients have been recommended to receive postoperative chemoradiation. Among 175 consecutive patients who had undergone total mesorectal excision, 120 completed postoperative chemoradiation (group A) and 55 patients declined to receive radiation therapy (group B). For the two groups, survival and recurrence rates were compared. Mean follow-up time was 24.7 months. There was no difference between two groups with regard to sex, mean age, stage of the disease, mean tumor height, type of operation and mean follow-up duration.
Overall recurrence rate showed no difference between the two groups (24.0% vs. 25.0%, P = 0.28). Local recurrence rate was also similar (10.0% vs. 6.0%, P = 0.11). There was no significant difference in duration to initial recurrence (14.0 months vs. 11.0 months, P = 0.18). The 5-year disease-free survival was 57% in group A and 63% in group B (P = 0.33). Disease-free survival in stage II was significantly better than in stage III. (78% vs. 42% overall, 70% vs. 37% in group A, 92% vs. 44% for group B, P < 0.01).
In this study, we found no beneficial effect of postoperative radiation therapy following total mesorectal excision for the rectal cancer. So far, the prognosis was critically dependent on the stage rather than presence or absence of radiotherapy after total mesorectal excision.
Hepato-gastroenterology 49(44):399-403. · 0.66 Impact Factor
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ABSTRACT: In this paper, we propose a new method of implementing bus operations on mesh wormhole routers with small additional circuits. The bus, called a virtual bus, is set up dynamically upon a request by bypassing existing datapath in wormhole routers. After bus setup, it acts as a real bus by sharing the point-to-point links of the corresponding row/column of the mesh. Simulation results show that the 2D (two-dimensional) mesh with the virtual bus outperforms the mesh with separate buses.
