Risk factors of unplanned intraoperative conversion to hand-assisted laparoscopic surgery or open surgery in laparoscopic liver resection.

BACKGROUND: Laparoscopic liver resection (LLR) is possible in many patients, but pure LLR is sometimes difficult to complete, and unplanned intraoperative hand-assisted laparoscopic surgery (HALS) or open conversion is sometimes necessary. However, appropriate indications and timing for conversion are unclear. This study aimed to clarify the indications for HALS and open conversion from pure LLR. METHODS: We collected data from 208 patients who underwent LLR from January 2010 to February 2021 in our department. We retrospectively examined these data between cases of unplanned intraoperative HALS conversion, open conversion, and pure LLR, and clarified risk factors and indications for HALS or open conversion. RESULTS: There were 191 pure LLRs, nine HALS conversions, and eight open conversions. In the HALS conversion group versus pure LLR group, body mass index (BMI) (27.0 vs. 23.7 kg/m2, p = 0.047), proportions of patients with history of upper abdominal surgery (78% vs. 33%; p = 0.006), repeat hepatectomy (56% vs. 15%; p = 0.002), S7 or S8 tumor location (67% vs. 35%; p = 0.049), and difficulty score (DS) ≥ 7 (56% vs. 19%; p = 0.008) were significantly higher, and surgical time (339 vs. 239 min; p = 0.031) was significantly longer. However, postoperative states were not significantly different between the two groups. The BMI cutoff value for risk of unplanned intraoperative conversion determined by receiver operating characteristic curve analysis was 25 kg/m2, and the proportion of patients with BMI ≥ 25 kg/m2 (89% vs. 31%, p < 0.001) was significantly higher in the HALS conversion versus pure LLR group. In the open conversion group, although there were no significant differences compared to the HALS group in clinicopathological factors except for sex, blood loss was greater (1425 vs. 367 mL; p < 0.001). CONCLUSION: Risk factors for considering HALS during LLR were patients with a history of upper abdominal surgery including repeat hepatectomy, BMI ≥ 25 kg/m2, S7 or S8 tumor location, DS ≥ 7, and prolonged surgical time. Furthermore, uncontrollable intraoperative bleeding was an indication for open conversion.

Surgical and oncological outcomes of laparoscopic versus open radical antegrade modular pancreatosplenectomy for pancreatic ductal adenocarcinoma.

PURPOSE: To compare the outcomes of laparoscopic radical antegrade modular pancreatosplenectomy (L-RAMPS) with those of open RAMPS (O-RAMPS) in patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: We reviewed, retrospectively, the medical records of 50 patients who underwent RAMPS for PDAC without resection of major vessels and adjacent organs between 2007 and 2019, and analyzed the relationship between the operative method and surgical and oncological outcomes. RESULTS: Nineteen of the 50 patients underwent L-RAMPS and 31 patients underwent O-RAMPS. L-RAMPS was associated with significantly less blood loss (P = 0.034) but a longer operative time (P = 0.001) than O-RAMPS. There were no significant differences in patient characteristics, tumor factors, or postoperative course; or in the rates of recurrence-free survival (P = 0.084) or overall survival (P = 0.402) between the L-RAMPS and O-RAMPS groups. CONCLUSION: L-RAMPS for PDAC resulted in less blood loss but a longer operative time than O-RAMPS. Although L-RAMPS may be feasible, the operative time needs to be reduced by standardizing the procedure.

Development of an artificial intelligence system using deep learning to indicate anatomical landmarks during laparoscopic cholecystectomy.

BACKGROUND: The occurrence of bile duct injury (BDI) during laparoscopic cholecystectomy (LC) is an important medical issue. Expert surgeons prevent intraoperative BDI by identifying four landmarks. The present study aimed to develop a system that outlines these landmarks on endoscopic images in real time. METHODS: An intraoperative landmark indication system was constructed using YOLOv3, which is an algorithm for object detection based on deep learning. The training datasets comprised approximately 2000 endoscopic images of the region of Calot's triangle in the gallbladder neck obtained from 76 videos of LC. The YOLOv3 learning model with the training datasets was applied to 23 videos of LC that were not used in training, to evaluate the estimation accuracy of the system to identify four landmarks: the cystic duct, common bile duct, lower edge of the left medial liver segment, and Rouviere's sulcus. Additionally, we constructed a prototype and used it in a verification experiment in an operation for a patient with cholelithiasis. RESULTS: The YOLOv3 learning model was quantitatively and subjectively evaluated in this study. The average precision values for each landmark were as follows: common bile duct: 0.320, cystic duct: 0.074, lower edge of the left medial liver segment: 0.314, and Rouviere's sulcus: 0.101. The two expert surgeons involved in the annotation confirmed consensus regarding valid indications for each landmark in 22 of the 23 LC videos. In the verification experiment, the use of the intraoperative landmark indication system made the surgical team more aware of the landmarks. CONCLUSIONS: Intraoperative landmark indication successfully identified four landmarks during LC, which may help to reduce the incidence of BDI, and thus, increase the safety of LC. The novel system proposed in the present study may prevent BDI during LC in clinical practice.

How Should We Treat Pancreatic Metastases from Renal Cell Carcinoma? A Meta-Analysis.

BACKGROUND: The treatment strategy for pancreatic metastasis (PM) from renal cell carcinoma (RCC) is unclear due to its rarity. The aim of this study was to reveal the role of surgery for PM from RCC. METHODS: A systematic literature search was conducted using PubMed and the Cochrane Library. The effectiveness of surgery for PM was evaluated based on the primary outcome of overall survival (OS), which was investigated in relation to surgical procedures and metastatic sites via subgroup analyses. RESULTS: There was no significant difference in the rate of 2-year OS between the surgery and control group (OR 0.43, 95% CI 0.14-1.26, P = 0.12). However, the rate of 5-year OS was significantly higher in the surgery group than the control group (OR = 0.41, 95% CI 0.18-0.93, P = 0.03). The rates of the complications and OS were not significantly different between radical and conservative pancreatectomies. The rate of 5-year OS of the patients with PM was higher than that with other metastases (OR 0.38, 95% CI 0.20-0.74, P = 0.004). CONCLUSION: Surgical resection for PM from RCC is associated with good prognosis. Limited surgery may be a useful option depending on the location of the lesion.

Short internal pancreatic stent reduces pancreatic fistula in pancreatoduodenectomy.

BACKGROUND: Clinically relevant postoperative pancreatic fistula (CR-POPF) is a major complication of pancreatoduodenectomy (PD). A pancreatic stent is usually used for drainage of the pancreatic duct, but the best type of the stent remains unclear. The aim of this study was to investigate perioperative factors and their influence on the risk of CR-POPF following PD. METHODS: From 2006 to 2019, the records of 246 patients who underwent PD were retrospectively reviewed, and the relationship between perioperative factors including type of pancreatic stent and CR-POPF was investigated. External or internal pancreatic stents were used for drainage of the pancreatic duct, and the internal stent was inserted 1 cm into the jejunum to decrease stent obstruction. RESULTS: External and internal pancreatic stents were used in 137 and 109 patients, respectively. Multivariate analysis revealed that the diameter of the main pancreatic duct (odds ratio = 0.292, 95% confidence interval = 0.140-0.605, P = 0.001), diagnosis (odds ratio = 3.359, 95% confidence interval = 1.498-7.693, P = 0.003), and type of pancreatic stent (odds ratio = 0.435, 95% confidence interval = 0.203-0.934, P = 0.033) were independent factors related to CR-POPF after PD. Internal stent was associated with a low rate of CR-POPF (P < 0.001) and short postoperative hospital stay (P < 0.001) compared to external stent. CONCLUSION: A short pancreatic internal stent could decrease the incidence of CR-POPF.

Relationship between the tumor location and clinicopathological features in left-sided pancreatic ductal adenocarcinoma.

PURPOSE: Although the same distal pancreatectomy (DP) is performed regardless of the location of left-sided pancreatic ductal adenocarcinoma (PDAC), the clinicopathological features may differ depending on the tumor location. The present study investigated the relationship between the tumor location and clinicopathological features in patients with left-sided PDAC. METHODS: The records of 59 patients who underwent DP for PDAC were enrolled. The relationship between the tumor location and clinicopathological features was investigated. The tumor location was classified into three groups according to the 7th AJCC/UICC TNM classification: body (Pb), body and tail (Pbt), and tail (Pt). RESULTS: Tumors were located at the Pb in 26 patients, Pbt in 15, and Pt in 18. There was no metastasis to the lymph nodes around the common hepatic artery in Pt. The rate of peritoneal dissemination in the Pt was higher than that in the Pb (P = 0.034) or Pbt (P = 0.002). There were no significant differences in the overall survival among the three groups. CONCLUSION: There was no metastasis to the lymph nodes around the common hepatic artery, and peritoneal dissemination was the most common site of recurrence in Pt tumors.

Altered glycosylation associated with dedifferentiation of hepatocellular carcinoma: a lectin microarray-based study.

BACKGROUND: Altered glycosylation associated with hepatocellular carcinoma (HCC) is well documented. However, few reports have investigated the association between dedifferentiation and glycosylation. Therefore, the aim of this study was to analyze glycosylation associated with dedifferentiation of HCC within the same nodule and to investigate glycosyltransferase related to the glycosylation. METHODS: We analyzed resected HCC specimens (n = 50) using lectin microarray to comprehensively and sensitively analyze glycan profiles, and identify changes to glycosylation between well- and moderately-differentiated components within the same nodule. Moreover, we performed immunohistochemical staining of mannosyl(α-1,3-)-glycoprotein ß-1,2-N-acetylglucosaminyltransferase (MGAT1), which is an essential glycosyltransferase that converts high-mannose glycans to complex- or hybrid-type N-glycans. RESULTS: Four lectins from Narcissus pseudonarcissus agglutinin (NPA), Concanavalin A, Galanthus nivalis agglutinin, and Calystegia sepium agglutinin were significantly elevated in moderately-differentiated components of HCC compared with well-differentiated components, and all lectins showed binding specificity to high-mannose glycans. Therefore, these structures were represented to a greater extent in moderately-differentiated components than in well-differentiated ones. Immunohistochemical staining revealed significantly increased NPA expression and decreased MGAT1 expression in moderately-differentiated components. Low MGAT1 expression in moderately-differentiated components of tumors was associated with intrahepatic metastasis and had tendency for poor prognosis. CONCLUSION: Dedifferentiation of well-differentiated HCC is associated with an increase in high-mannose glycans. MGAT1 may play a role in the dedifferentiation of HCC.

Fucosyltransferase 8 plays a crucial role in the invasion and metastasis of pancreatic ductal adenocarcinoma.

PURPOSE: Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer. It is an aggressive malignancy associated with poor prognosis because of recurrence, metastasis, and treatment resistance. Aberrant glycosylation of cancer cells triggers their migration and invasion and is considered one of the most important prognostic cancer biomarkers. The current study aimed to identify glycan alterations and their relationship with the malignant potential of PDAC. METHODS: Using a lectin microarray, we evaluated glycan expression in 62 PDAC samples. Expression of fucosyltransferase 8 (FUT8), the only enzyme catalyzing core fucosylation, was investigated by immunohistochemistry. The role of FUT8 in PDAC invasion and metastasis was confirmed using an in vitro assay and a xenograft peritoneal metastasis mouse model. RESULTS: The microarray data demonstrated that core fucose-binding lectins were significantly higher in carcinoma than in normal pancreatic duct tissues. Similarly, FUT8 protein expression was significantly higher in carcinoma than in normal pancreatic duct tissues. High FUT8 protein expression was significantly associated with lymph-node metastases and relapse-free survival. FUT8 knockdown significantly reduced the invasion in PDAC cell lines and impaired peritoneal metastasis in the xenograft model. CONCLUSIONS: The findings of this study provide evidence that FUT8 plays a pivotal role in PDAC invasion and metastasis and might be a therapeutic target for this disease.

Clinical significance of upper gastrointestinal endoscopy before laparoscopic bariatric procedures in Japanese patients.

PURPOSES: The choice between performing routine and selective upper gastrointestinal endoscopy (UGE) before bariatric surgery remains controversial. This study aimed to evaluate the clinical significance of UGE before laparoscopic bariatric procedures. METHODS: We enrolled 155 obese Japanese patients who underwent laparoscopic bariatric procedures at our institute and evaluated their endoscopic findings, such as reflux esophagitis (RE), hiatal hernia (HH), Barrett's esophagus, gastritis, duodenitis, gastroduodenal ulcer, gastric cancer, and polyps. RESULTS: Preoperative endoscopy revealed abnormal findings in 102 patients (66%), including gastritis in 57 (37%), HH in 51 (32%), RE in 27 (17%), benign gastric polyps in 16 (10%), duodenitis in 6 (4%), and Barrett's esophagus in 1 (0.6%). Two patients with definite HH were treated with simultaneous crural repair at the time of bariatric surgery. Duodenitis was graded as severe in three of these six patients and treated with a proton pump inhibitor before surgery. Eleven patients received therapy to eradicate Helicobacter pylori (H. pylori), either before or after the surgery. In summary, preoperative endoscopy changed the perioperative management for 16 of the 155 patients (10%). CONCLUSIONS: Routine UGE may be necessary before bariatric procedures in obese Japanese patients.

Additional effects of duodenojejunal bypass on glucose metabolism in a rat model of sleeve gastrectomy.

PURPOSE: Sleeve gastrectomy with duodenojejunal bypass (SG-DJB) is expected to become a popular procedure in East Asia. The aim of this study was to evaluate the effects of duodenojejunal bypass on glucose metabolism in a rat model of sleeve gastrectomy (SG). METHODS: Twenty-four Sprague-Dawley rats were divided into two groups: SG-DJB and SG alone. 6 weeks after surgery, body weight, feed intake, and metabolic parameters were measured, and oral glucose tolerance tests (OGTT) were performed. The mRNA expression of factors related to gluconeogenesis and glucose transport was evaluated using jejunal samples. Protein expression of factors with significantly different mRNA expression levels was evaluated using immunohistochemistry. RESULTS: Body weight and metabolic parameters did not significantly differ between the two groups. During the OGTT, the SG-DJB group showed an early increase in serum insulin followed by an early decrease in blood glucose compared with the SG group. Expression levels of glucose transporter 1 (GLUT1) and sodium-glucose cotransporter 1 (SGLT1) mRNA and protein in the alimentary limb (AL) were greater in the SG-DJB group than in the SG group. CONCLUSIONS: The additional effects of duodenojejunal bypass on glucose metabolism after SG may be related to increased expression of GLUT1 and SGLT1 in the AL.

[IPMC of the pancreas with enlarged para-aortic lymph nodes with a high accumulation of FDG-PET:a case report].

A 74-year-old man was admitted for evaluation of a pancreatic tumor. Abdominal CT revealed a multilocular cystic tumor with thickened septal walls and an enhanced mural nodule in the head of the pancreas, as well as enlarged para-aortic lymph nodes. FDG-PET revealed FDG accumulation in the nodule and in the para-aortic nodes. The tumor was diagnosed as intraductal papillary mucinous carcinoma (IPMC) with para-aortic lymph node metastases. After 2 courses of chemotherapy with gemcitabine and nab-paclitaxel, the tumor decreased slightly in size, but the lymph nodes did not change. Surgery was then performed. Intraoperative pathology examination confirmed that the para-aortic lymph nodes had only inflammatory swelling. Accordingly, pylorus-preserving pancreaticoduodenectomy was performed. Histopathology examination revealed atypical cells without invasion, and IPMC (TisN0M0;stage 0) was diagnosed. It is thus important for selection of the appropriate treatment approach to determine if enlarged para-aortic lymph nodes are benign or malignant.

Prognostic factors of non-ampullary duodenal adenocarcinoma.

BACKGROUND: Non-ampullary duodenal adenocarcinoma, excluding carcinoma in the ampulla of Vater, is a rare disease. Although several prognostic factors have been reported, they remain controversial due to the rarity of non-ampullary duodenal adenocarcinoma. The aims of this study were to investigate prognostic factors in patients with non-ampullary duodenal adenocarcinoma and to assess chemotherapy in patients with recurrence. PATIENTS AND METHODS: Records of 25 patients who underwent surgical treatment for non-ampullary duodenal adenocarcinoma from 2004 to 2016 were retrospectively reviewed. The relationship between the clinicopathological factors and outcomes was investigated. RESULTS: Serum level of CA19-9, gross appearance, tumor size, tumor invasion, lymph node metastases, TNM stage and lymphatic and vascular invasion were significant risk factors of recurrence. Patients with recurrence who received chemotherapy according to regimens used to treat colorectal cancer had a better prognosis than those without chemotherapy (P = 0.016). CONCLUSION: Advanced non-ampullary duodenal adenocarcinoma has a poor prognosis, but chemotherapy possibly improves the prognosis in the patients with recurrent non-ampullary duodenal adenocarcinoma.

Control of inferior vena cava injury during laparoscopic surgery using a double balloon-equipped central venous catheter: proof of concept in a live porcine model.

BACKGROUND: Iatrogenic inferior vena cava (IVC) injury is a rare but potentially life-threatening complication during laparoscopic surgery. This experimental study aimed to assess the hemostatic ability of a new device, double balloon-equipped central venous (DB-CV) catheter, for IVC injury. METHODS: The DB-CV catheter comprises a triple-lumen sphincterotome combined with two dilating balloons having a diameter of 25 mm. The experimental procedures were performed in five pigs. The DB-CV catheter was inserted via the right femoral vein. For the IVC occlusion test, correct placement of the balloons was confirmed by indocyanine green fluorescence imaging, and hemodynamic data were recorded. For the IVC injury test, a 3- to 4-mm circumferential incision was created in IVC, and hemostasis was initiated using balloon inflation 5 s after the injury. RESULTS: Hemodynamic changes were minimal, with a 20 mmHg reduction in the mean arterial pressure because of IVC occlusion. All bleeding from IVC injuries was successfully temporarily stopped by direct balloon compression, with a mean time to hemostasis of 69 s and mean blood loss of 32 ml. Subsequently, the positioning of IVC injuries between two balloons made it possible to suture the injured IVC. CONCLUSIONS: Balloon occlusion using the DB-CV catheter provides a rapid temporal hemostatic effect and can overcome the serious condition of massive hemorrhage from IVC injuries.

Laparoscopic liver resection in cirrhotic patients with specific reference to a difficulty scoring system.

PURPOSE: Laparoscopic liver resection is widely used for liver tumors, but its utility in patients with cirrhosis remains controversial. The aim of this study was to assess the surgical outcomes of laparoscopic liver resection in patients with liver cirrhosis with specific reference to a difficulty scoring system. METHODS: From January 2010 to March 2016, the outcomes of laparoscopic liver resection in 95 patients were retrospectively reviewed. Surgical outcomes were analyzed to identify differences between the liver cirrhosis and non-liver cirrhosis groups; these groups were further stratified to high and low difficulty scores. The surgical outcomes of both groups were compared according to the difficulty scores. RESULTS: Overall, 53/95 (55.8%) patients were diagnosed with liver cirrhosis. There were no significant differences in surgical duration, blood loss, postoperative hospital stay, and morbidity between groups, although liver function was worse in the liver cirrhosis group than in the non-liver cirrhosis group. Multivariate analysis showed that the difficulty score was an independent predictor of increased blood loss. In particular, blood loss in cirrhotic patients was significantly greater with a high difficulty score than with a low difficulty score. CONCLUSIONS: The safety profile of laparoscopic liver resection was the same in patients with and without liver cirrhosis. However, patients with liver cirrhosis and a high difficulty score require extra attention, because of a higher risk for perioperative blood loss.

Long-term outcomes of laparoscopic versus open splenectomy for immune thrombocytopenia.

PURPOSE: Splenectomy is the standard therapy for medically refractory immune thrombocytopenia (ITP). Laparoscopic splenectomy (LS) has gained wide acceptance; however, the long-term outcomes of LS versus open splenectomy (OS) for patients with ITP remain unclear. METHODS: We analyzed, retrospectively, 32 patients who underwent splenectomy, as LS in 22 and OS in 10, for refractory ITP at our institute. Data were evaluated based on the American Society of Hematology 2011 evidence-based practice guidelines for ITP. RESULTS: Although the operation time was significantly longer in the LS group (p < 0.01), LS was associated with less blood loss (p < 0.01), infrequent blood transfusion during surgery (p < 0.01), quicker resumption of oral intake (p < 0.01), and shorter hospital stay (p < 0.01) than OS. Positive responses, including complete and partial remission, were achieved in 90% of the OS group patients and 77% of the LS group patients. The mean follow-up periods were 183 and 92 months, respectively. Relapse-free survival rates, 15 years after the operation were 63% in the OS group and 94% in the LS group. CONCLUSIONS: LS can provide better short-term results and comparable long-term results to those of OS for ITP.

Secondary Unconjugated Bile Acids Induce Hepatic Stellate Cell Activation.

Hepatic stellate cells (HSCs) are key players in liver fibrosis, cellular senescence, and hepatic carcinogenesis. Bile acids (BAs) are involved in the activation of HSCs, but the detailed mechanism of this process remains unclear. We conducted a comprehensive DNA microarray study of the human HSC line LX-2 treated with deoxycholic acid (DCA), a secondary unconjugated BA. Additionally, LX-2 cells were exposed to nine BAs and studied using immunofluorescence staining, enzyme-linked immunosorbent assay, and flow cytometry to examine the mechanisms of HSC activation. We focused on the tumor necrosis factor (TNF) pathway and revealed upregulation of genes related to nuclear factor kappa B (NF-κB) signaling and senescence-associated secretory phenotype factors. α-Smooth muscle actin (α-SMA) was highly expressed in cells treated with secondary unconjugated BAs, including DCA, and a morphological change associated with radial extension of subendothelial protrusion was observed. Interleukin-6 level in culture supernatant was significantly higher in cells treated with secondary unconjugated BAs. Flow cytometry showed that the proportion of cells highly expressing α-SMA was significantly increased in HSCs cultured with secondary unconjugated BAs. We demonstrated that secondary unconjugated BAs induced the activation of human HSCs.

Fucosylation is associated with the malignant transformation of intraductal papillary mucinous neoplasms: a lectin microarray-based study.

PURPOSE: Intraductal papillary mucinous neoplasm (IPMN) is an intraductal mucin-producing pancreatic neoplasm with the potential for malignant transformation. Changes in glycans expressed on the cell surface and glycotransferases play important roles in malignant transformation. We conducted this study to analyze glycan alterations in IPMNs by using a lectin microarray and to identify the factors associated with altered glycans and their relationships with malignant transformation. METHODS: Using a lectin microarray, we evaluated glycan expression in 22 samples of IPMN with carcinoma, obtained from curative resections performed in our department. We also used immunohistochemistry to investigate fucosyltransferase 8 (Fut 8) protein expression, which is associated with glycan alterations in IPMNs. RESULTS: The lectin microarray demonstrated that only two lectins, Aleuria aurantia lectin (AAL) and Aspergillus oryzae L-fucose-specific lectin (AOL), which bind to fucose, exhibited significant sequential increases from normal pancreatic duct to adenoma and carcinoma. Similarly, Fut 8 protein expression, which is associated with AAL and AOL, sequentially and significantly increased from the normal pancreatic duct to adenoma and carcinoma. CONCLUSIONS: Lectin microarray analysis suggested that fucosylation is associated with the malignant transformation of IPMNs.

Effects of different pressure levels of CO2 pneumoperitoneum on liver regeneration after liver resection in a rat model.

BACKGROUND: A recent study demonstrated that high pressure of carbon dioxide (CO2) pneumoperitoneum before liver resection impairs postoperative liver regeneration. This study was aimed to investigate effects of varying insufflation pressures of CO2 pneumoperitoneum on liver regeneration using a rat model. METHODS: 180 male Wistar rats were randomly divided into three groups: control group (without preoperative pneumoperitoneum), low-pressure group (with preoperative pneumoperitoneum at 5 mmHg), and high-pressure group (with preoperative pneumoperitoneum at 10 mmHg). After pneumoperitoneum, all rats were subjected to 70% partial hepatic resection and then euthanized at 0 min, 12 h, and on postoperative days (PODs) 1, 2, 4, and 7. Following outcome parameters were used: liver regeneration (liver regeneration rate, mitotic count, Ki-67 labeling index), hepatocellular damage (serum aminotransferases), oxidative stress [serum malondialdehyde (MDA)], interleukin-6 (IL-6), and hepatocyte growth factor (HGF) expression in the liver tissue. RESULTS: No significant differences were observed for all parameters between control and low-pressure groups. The liver regeneration rate and mitotic count were significantly decreased in the high-pressure group than in control and low-pressure groups on PODs 2 and 4. Postoperative hepatocellular damage was significantly greater in the high-pressure group on PODs 1, 2, 4, and 7 compared with control and/or low-pressure groups. Serum MDA levels were significantly higher in the high-pressure group on PODs 1 and 2, and serum IL-6 levels were significantly higher in the high-pressure group at 12 h and on POD 1, compared with control and/or low-pressure groups. The HGF tissue expression was significantly lower in the high-pressure group at 12 h and on PODs 1 and 4, compared with that in control and/or low-pressure groups. CONCLUSIONS: High-pressure pneumoperitoneum before 70% liver resection impairs postoperative liver regeneration, but low-pressure pneumoperitoneum has no adverse effects. This study suggests that following laparoscopic liver resection using appropriate pneumoperitoneum pressure, no impairment of liver regeneration occurs.

Effects of the dihydrolipoyl histidinate zinc complex against carbon tetrachloride-induced hepatic fibrosis in rats.

PURPOSE: This study investigated the effects of an antioxidant, dihydrolipoyl histidinate zinc complex (DHLHZn), on the hepatic fibrosis in the carbon tetrachloride (CCl4) rat model. METHODS: The animals were divided into three groups: control, CCl4, and CCl4+DHLHZn. A histological assessment of the liver fibrosis was performed using stained liver samples. The oxidative stress and antioxidant levels were evaluated by measuring the malondialdehyde (MDA) and glutathione (GSH) levels in the liver. In addition, cultured human hepatic stellate cells (LI90) were exposed to antimycin-A (AMA) and divided into four groups: control, DHLHZn, AMA, and AMA+DHLHZn. The effects of DHLHZn on AMA-induced fibrosis were evaluated by measuring the expression of transforming growth factor (TGF)-ß1 and collagen α1 (I). RESULTS: The hepatic fibrosis in the CCl4+DHLHZn group was attenuated compared to that in the CCl4 group. The MDA levels in the CCl4+DHLHZn group were significantly lower than those of the CCl4 group, whereas the GSH levels in the CCl4+DHLHZn group were significantly higher than those of the CCl4 group. Furthermore, the relative mRNA expression of TGF-ß1 and collagen α1 (I) in the AMA+DHLHZn group was significantly lower than that in the AMA group. CONCLUSION: DHLHZn may attenuate the hepatic fibrosis induced by CCl4 by decreasing the degree of oxidative stress.

Increased oxidative stress may lead to impaired adaptive cytoprotection in the gastric mucosa of portal hypertensive rat.

BACKGROUND AND AIMS: In the gastric mucosa of portal hypertensive rats, adaptive cytoprotection against ethanol-induced damage is impaired. The aim of this study was to determine relation between impaired adaptive cytoprotection and oxidative stress. METHODS: Portal hypertension was produced in male Sprague-Dawley rats by inducing staged portal vein occlusion. Oxidative stress levels were evaluated by measuring malondialdehyde and nitrotyrosine levels in the rat gastric mucosa with or without 10% ethanol pretreatment. Inhibition of oxidative stress by an anti-oxidant agent was estimated, and glutathione levels were also measured. Adaptive cytoprotection to 70% ethanol treatment was evaluated by measuring the gastric mucosal injury index in the presence or absence of the anti-oxidant. RESULTS: The portal hypertensive gastric mucosa pretreated with 10% ethanol had significantly higher oxidative stress levels than the mucosa not pretreated with 10% ethanol. However, the sham-operated gastric mucosa pretreated with 10% ethanol had significantly lower oxidative stress levels than the mucosa not pretreated with 10% ethanol. Pretreatment with 10% ethanol increased glutathione levels in the sham-operated but not in the portal hypertensive gastric mucosa. Administration of the anti-oxidant agent prior to 10% ethanol pretreatment significantly reduced oxidative stress levels, increased glutathione levels, and decreased the injury index in response to 70% ethanol in the portal hypertensive gastric mucosa. CONCLUSION: Increased oxidative stress may lead to impaired adaptive cytoprotection in the gastric mucosa of portal hypertensive rats, probably through damage to the system of endogenous anti-oxidant production.