Cryopreserved porcine hepatocytes: expression and induction of cytochrome P450, isoform CYP2E1.

Cryopreservation of porcine hepatocytes for their use in bioartificial liver devices may result in reduced cytochrome P450 (CYP) enzyme activity. The aim of this study was to assess the effects of several CYP inducers on the isoform CYP2E1 protein expression in cryopreserved porcine hepatocytes. Isolated porcine hepatocytes were cryopreserved for 1 month, thawed, and cultured for 3 days. During medium culture, the hepatocytes were exposed to the following CYP inducers: dimethyl sulfoxide, rifampicin, phenobarbital, 3-methylcholanthrene, and dexamethasone. CYP2E1 protein expression was determined by immunoblotting. CYP2E1 protein levels were constantly detected in cryopreserved porcine hepatocytes. CYP inducers did not modify CYP2E1 protein levels. Long-term cryopreserved porcine hepatocytes preserved their capacity for CYP2E1 protein expression, although exposure of these hepatocytes to CYP inducers did not modify the CYP2E1 protein expression.

Peritoneal implantation of cryopreserved encapsulated porcine hepatocytes in rats without immunosuppression: viability and function.

The bioartificial liver (BAL) represents a promising approach to cell transplantation without immunosuppression as a method to support patients with hepatic insufficiency. The aim of this study was to assess viability and function of cryopreserved encapsulated porcine hepatocytes implanted intraperitoneally in rats without immunosuppression. Isolated porcine hepatocytes were cryopreserved at -196 degrees C for 1 month. Four groups were created: group 1 (n=10), freshly encapsulated porcine hepatocytes cultured in albumin-free medium for 10 days; group 2 (n=10), freshly encapsulated porcine hepatocytes implanted in the rat peritoneum without immunosuppression for 1 month and cultured for 10 days after explantation; group 3 (n=10), cryopreserved encapsulated porcine hepatocytes cultured for 10 days; group 4 (n=10), cryopreserved encapsulated porcine hepatocytes implanted in the rat peritoneum without immunosuppression for 1 month and cultured for 10 days after explantation. We assessed urea and albumin production and hepatocyte viability. The hepatocytes of all groups retained the capacity to produce urea and albumin, although the albumin synthesis was significantly decreased among hepatocytes of group 4 (P< .01). Encapsulated cryopreserved porcine hepatocytes explanted from rat peritoneum after 1 month appeared morphologically viable; their ultrastructure was preserved. In conclusion, long-term cryopreservation of porcine hepatocytes resulted in retention of their biological activity and in significant viability when transplanted into the rat peritoneum without immunosuppression.

Clinical evaluation of fibrin glue in the prevention of anastomotic leak and internal hernia after laparoscopic gastric bypass: preliminary results of a prospective, randomized multicenter trial.

BACKGROUND: Gastro-jejunal anastomotic leak and internal hernia can be life-threatening complications of laparoscopic Roux-en-Y gastric bypass (LRYGBP), ranging from 0.1-4.3% and from 0.8-4.5% respectively. The safety and efficacy of a fibrin glue (Tissucol) was assessed when placed around the anastomoses and over the mesenteric openings for prevention of anastomotic leaks and internal hernias after LRYGBP. METHODS: A prospective, randomized, multicenter, clinical trial commenced in January 2004. Patients with BMI 40-59 kg/m2, aged 21-60 years, undergoing LRYGBP, were randomized into: 1) study group (fibrin glue applied on the gastro-jejunal and jejuno-jejunal anastomoses and the mesenteric openings); 2) control group (no fibrin glue, but suture of the mesenteric openings). 322 patients, 161 for each arm, will be enrolled for an estimated period of 24 months. Sex, age, operative time, time to postoperative oral diet and hospital stay, early and late complications rates are evaluated. An interim evaluation was conducted after 15 months. RESULTS: To April 2005, 204 patients were randomized: 111 in the control group (mean age 39.0+/-11.6 years, BMI 46.4 +/- 8.2) and 93 in the fibrin glue group (mean age 42.9+/-11.7 years, BMI 46.9+/-6.4). There was no mortality or conversion in both groups; no differences in operative time and postoperative hospital stay were recorded. Time to postoperative oral diet was shorter for the fibrin glue group (P = 0.0044). Neither leaks nor internal hernias have occurred in the fibrin glue group. The incidence of leaks (2 cases, 1.8%) and the overall reoperation rate were higher in the control group (P=0.0165). CONCLUSION: The preliminary results suggest that Tissucol application has no adverse effects, is not time-consuming, and may be effective in preventing leaks and internal hernias in morbidly obese patients undergoing LRYGBP.

Laparoscopic subtotal colectomy with cecorectal anastomosis for slow-transit constipation.

Subtotal colectomy with cecorectal anastomosis represents an interesting alternative to total colectomy with ileorectal anastomosis. Several technical variants to the methods for performing the anastomosis between the cecum and the rectal stump after subtotal colectomy have been reported. The mechanical, antiperistaltic, end-to-end cecorectal anastomosis is safe and easy to perform. The authors aimed to assess the safety and feasibility of this technique performed laparoscopically in a series of four patients. All the procedures were completed laparoscopically. The mean time for surgery was 200 min (range, 180-220 min). There was no mortality and no postoperative complications. The mean hospital stay was 4 days (range, 3-5 days). This technique can be performed laparoscopically with all the advantages inherent to the minimally invasive approach.

[Morbid obesity, public health problem: laparoscopic surgical treatment]. / L'obésité morbide, problème de santé publique: traitement chirurgical sous laparoscopie.

Morbid obesity, commonly defined as a condition in which the weight exceed twice the ideal body weight, is a major public health concern, widely unrecognized in France whereas causing 55,000 deaths per year to compare to 8,000 deaths per year by traffic accidents. Its pathogenesis is discussed even if much attention in recent years has centered on genetic causes since the identification of the ob-gene and its protein product leptin. Due to the long term failure of medical treatments, the advent of laparoscopy had disrupted therapeutic and carried on exponential development of laparoscopic operations mainly by gastric banding using an adjustable ring not without complications. It is why we have performed a prospective study by laparoscopy in 100 patients comparing 3 operations with the aim that each indication could be adapted to the alimentary behaviour. The short term results are extremely favourable and comparable to international literature data. Moreover, the study is a plea for a multidisciplinary approach of morbid obesity and a core for a public health action.

[Surgical treatment of anterior rectoceles in women. The transanal approach]. / Traitement chirurgical de la rectocèle antérieure de la femme. La voie transanale.

Anterior rectocele is a herniation of the anterior rectal wall into the vagina, which may be either isolated or associated with other pelvic floor disorders. Rectocele could result in outlet obstruction with dyschezia, manual extraction of faeces and/or false incontinence. Rectocele is diagnosed clinically, and can be confirmed by defecography. Other tests may demonstrate associated causes of constipation. Symptomatic rectoceles can be treated via a transrectal route, with two or three layers of plication of the rectal wall and excision of the redundant mucosal flap. The results of transrectal repair are good: short hospital stay, no mortality, morbidity less than 5%, good short- and mid-term results in approximately 80% of cases. Selection criteria in favour of the transrectal approach have not been clearly identified.

Caspase inhibition protects from liver injury following ischemia and reperfusion in rats.

Normothermic ischemia and reperfusion of the liver results in microcirculatory failure followed by necrosis and cell death. Recently, another type of cell death, apoptosis or programmed cell death, was found to be activated during the early phase of reperfusion after liver ischemia. Caspases are cysteine proteinases specifically involved in the initiation and execution phases of apoptosis. The aim of this study was to demonstrate that inhibition of apoptosis by a specific inhibitor of caspases might protect the liver against ischemia/reperfusion injury. Rats were divided into three groups: group 1, control, PBS administration; group 2, Z-Asp-cmk (Z-Asp-2,6-dichlorobenzoyl-oxymethylketone) treatment; group 3, sham-operated control animals. Z-Asp-cmk (0.5 mg Z-Asp-cmk dissolved in 300 microl PBS solution containing 1% DMSO) was injected intravenously, 2 min prior to induction of 120 min ischemia. Survival rates were compared and serum activities of aspartate aminotransferases and alanine aminotransferases were assessed in the blood collected from the suprahepatic vena cava. Histology of the liver was assessed 6 h after the end of ischemia. Apoptosis was detected by the terminal deoxynucleotidyl transferase-mediated dUTP-FITC nick end-labeling method (TUNEL method) and by electrophoresis for analysis of DNA fragmentation. Caspase activity was determined by measuring hydrolysis of the CPP32-like substrate Ac-DEVD-pNA and absorption of paranitroaniline. Z-Asp-cmk treatment significantly increased 7-day survival (95%) compared with that in nontreated rats (30%, P < 0.001). Serum activities of aminotransferases and the extent of liver congestion and necrosis were significantly (P < 0.001) decreased after treatment with Z-Asp-cmk. TUNEL-positive cells were detected 3-6 h after reperfusion in the control group. In Z-Asp-cmk pretreated rats, a dramatic decrease in the number of TUNEL-positive cells was observed. Analysis of DNA fragmentation of freshly isolated hepatocytes confirmed these results. Caspase activity was increased 3-6 h after reperfusion in the control group, but significantly (P < 0.001) decreased after treatment with Z-Asp-cmk. These findings demonstrate that liver injury following ischemia and reperfusion can be prevented by inhibition of caspases. Caspase inhibitors may have important implications for therapy in liver disease and after liver transplantation.

Laparoscopic repair of chronic intrathoracic gastric volvulus.

BACKGROUND: Totally intrathoracic gastric volvulus is an uncommon presentation of hiatal hernia, in which the stomach undergoes organoaxial torsion predisposing the herniated stomach to strangulation and necrosis. This may occur as a surgical emergency, but some patients present with only chronic, non-specific symptoms and can be treated electively. The aim of this study is to describe a comprehensive approach to laparoscopic repair of chronic intrathoracic gastric volvulus and to critically assess the pre-operative work-up. METHODS: Eight patients (median age, 71 years) underwent complete laparoscopic repair of chronic intrathoracic gastric volvulus. Symptoms of epigastric pain and early satiety were universally present. Five patients had reflux symptoms. The diagnostic evaluation included a video esophagogram, upper endoscopy, 24-hour pH measurement, and esophageal manometry in all patients. Operative results and postoperative outcome were recorded and follow-up at 1 year included a barium swallow in all patients. RESULTS: All patients had documented intrathoracic stomach. Five of 8 patients had a structurally normal lower esophageal sphincter. All 4 patients with reflux esophagitis on upper endoscopy had a positive 24-hour pH study, and 2 of these patients had a structurally defective lower esophageal sphincter on manometry. None of the patients had preoperative evidence of esophageal shortening. All procedures were completed laparoscopically. The procedure included reduction of the stomach into the abdomen, primary closure of the diaphragmatic defect, and the construction of a short, floppy Nissen fundoplication. There were no major complications. One patient required repair of a trocar site hernia 6 months postoperatively. At 1-year follow-up, there were no radiologic recurrences of the volvulus. One patient complained of temporary swallowing discomfort and another had recurrent gastroesophageal reflux disease (GERD) symptoms caused by a breakdown of the wrap. All other patients remained asymptomatic during follow-up. CONCLUSIONS: The repair of chronic gastric volvulus can be accomplished successfully with a laparoscopic approach. A preoperative endoscopy and esophagogram are crucial to detect esophageal stricture or shortening, and manometry is needed to access esophageal motility; pH measurements do not affect operative strategy. The procedure should include a Nissen fundoplication to treat preoperative GERD, to prevent possible postoperative GERD, and to secure the stomach in the abdomen. The procedure is safe but technically challenging, requiring previous laparoscopic foregut surgical expertise.

Possibilities of laparoscopic liver resection.

The aim of this study was to report the results of our experience in liver surgery by laparoscopy. From 1989 to 1996, 30 patients (20 women, 10 men; age, 23-88 years; mean age, 53.9 years) underwent laparoscopic liver surgery at our Institute for the following pathology: 10 for biliary cysts, 7 for polycystic diseases, 8 for benign tumors, 3 for hydatid cysts, 1 for chronic abscess, and 1 for metastasis. The locations of these lesions were: 19 in the left lobe, 4 in the right lobe, and 7 in both lobes. Their average size was 8. 45 cm (range, 2.5-22 cm). The largest lesions were biliary cysts; among benign tumors, the maximum diameter was 8 cm. Surgical treatment was as follows: 17 deroofings, 3 pericystectomies, 7 tumorectomies, and 3 left lobectomies. The mean operative time was 79 min (range, 45-527 min). Three of the 30 laparoscopic procedures (10%) were converted to open surgery, because of bleeding in 2 patients with polycystic disease and because it was impossible to carry out the dissection in 1 patient with liver-cell adenoma adjacent to the left portal branch. There were no deaths in this series and 6 patients showed morbidity: 2 patients with polycystic disease developed ascites and required intensive care unit recovery, 1 patient had phlebitis, 1 had infection of the urinary tract, and 2 had local septic complications. Preliminary findings show that the laparoscopic approach to liver lesions may represent safe and effective treatment in selected patients, on condition that several technical details are respected. Of fundamental importance are the surgical equipment, the presence of two experienced operators to do four-hands surgery, and the careful selection of indications, reserving laparoscopic treatment only for those lesions located in easily accessible areas, mainly in the lateral and anterior hepatic segments.

Laparoscopic management of benign cystic lesions of the liver.

We present our experience in the laparoscopic management of benign liver cysts. The aim of the study was to analyze the technical feasibility of such management and to evaluate safety and outcome on follow-up. Between September 1990 and October 1997, 31 patients underwent laparoscopic liver surgery for benign cystic lesions. Indications were: solitary giant liver cysts (n = 16); polycystic liver disease (PLD; n = 9); and hydatid cysts (n = 6). All giant solitary liver cysts were considered for laparoscopy. Only patients with PLD and large dominant cysts located in anterior liver segments, and patients with large hydatid cysts, regardless of segment or small partially calcified cysts in a safe laparoscopic segment, were included. Patients with cholangitis, cirrhosis, and significant cardiac disease were excluded. Data were collected prospectively. The procedures were completed laparoscopically in 29 patients. The median size of the solitary liver cysts was 14 cm (range, 7-22 cm). Conversion to laparotomy occurred in 2 patients (6.4%), to control bleeding. The median operative time was 141 min (range, 94-165 min) for patients with PLD and 179 min (range, 88-211 min) for patients with hydatid cysts. All solitary liver cysts were fenestrated in less than 1 h. There were no deaths. Complications occurred in 6 patients (19%). Two hemorrhagic and two infectious complications were noted after management of hydatid cysts. Three patients were transfused. The median length of hospital stay was 1.3 days (range, 1-3 days), 3 days (range, 2-7 days), and 5 days (range, 2-17 days) for solitary cyst, PLD, and hydatid cysts, respectively. Median follow-up was 30 months (range, 3-78 months). There was no recurrence of solitary liver cyst or hydatid cysts. One patient with PLD presented with symptomatic recurrent cysts at 6 months, requiring laparotomy. We conclude that laparoscopic liver surgery can be accomplished safely in patients with giant solitary cysts, regardless of location. The laparoscopic management of polycystic liver disease should be reserved for patients with a limited number of large, anteriorly located cysts. Hydatid disease is best treated through an open approach.

Posterior vagotomy and anterior seromyotomy as elective surgery for duodenal ulcer disease.

BACKGROUND/AIMS: The introduction of acid-reductor drugs in the treatment of duodenal ulcer has led to a drastic reduction in surgical indications. The role of Helicobacter pylori in recurrence and persistence of ulcer has added antibiotics to H2-receptor blockers and proton pump inhibitors. As this triple drug therapy always involves long and short-term side effects and ulcer recurrence is frequent once medication is stopped, surgical treatment with its recognized long-term efficacy has a role to play in prevention of complications. Posterior truncal vagotomy and anterior seromyotomy will guarantee complete denervation of the posterior territory and hence post-vagotomy diarrhea is avoided and motility is maintained in the pyloric and antral regions. METHODOLOGY: Elective posterior vagotomy and anterior seromyotomy was performed on 75 patients (14 F, 61 M) aged 19-61 years with a duodenal ulcer refractory to medical treatment. Sixty-two of them were followed-up for at least 2 years. Vagotomy is performed with the patient in the same position as for cholecystectomy. Five trocars are routinely inserted. The procedure involves three steps: approach for the hiatal region, posterior vagotomy, and anterior seromyotomy. RESULTS: Mean operative time was 140 min (range: 120-220 min). There was no mortality and only one case of pneumothorax which was treated successfully by a chest drainage. As for long-term, one patient developed reflux esophagitis. Fifty-nine patients had healing of their ulcer and 3 other patients had presence of scars 2 months after the operation. Post-operative BAO decreased to 78% and pentagastrin-stimulated acid secretion to 80%. Two pre-pyloric ulcer recurrences occurred 2 years after surgery, which responded to medical therapy. At 2 years, a 65% reduction in both BAO and pentagastrin-stimulated acid secretion was recorded. CONCLUSIONS: Posterior truncal vagotomy with anterior seromyotomy combines the rapidity and effectiveness of truncal vagotomy, which has the advantage of maintaining the gastric antral pump with ultra selective vagotomy. This minimally invasive surgical approach has opened up a new era in effective treatment of ulcer disease, and from now on must represent an alternative to long-term medical therapy.

[The biocompatibility of suture materials used in colon surgery. An experimental study in the rat]. / Biocompatibilità dei materiali di sutura in uso nella chirurgia del colon. Studio sperimentale nel ratto.

BACKGROUND: The aim of this experimental study was to compare the tissue behavior of biofragmentable anastomotic ring (BAR) with other synthetic materials used in colonic surgery. METHODS: Thirty-three rats were divided into four groups: group 1, sham-operated control animals without material implanted; group 2, with fragments of polypropylene monofilament implanted extraperitoneally in abdominal wound, between musculature and peritoneum; group 3, with metal clips implanted extraperitoneally in abdominal wound, between musculature and peritoneum and group 4, with fragments of biofragmentable anastomotic ring implanted extraperitoneally in abdominal wound, between musculature and peritoneum. Animals were sacrificed 30 days after the operation. Macroscopic and histological criteria were used to characterize the resistance of the wound and the tolerance of the host to the foreign material. RESULTS: The inflammatory cell reaction of host tissue was significantly greater in group 4 compared with other groups (p < 0.05). In three cases, in group 4, we observed the adhesion of implanted fragment to epiploa. The enumeration of giant cells and the degree of fibrotic reaction was similar in all groups with material implanted, but no significant difference between the groups was observed. Our findings showed the greater biocompatibility of polypropylene and metallic clips, compared to the biofragmentable ring anastomosis. The strong inflammatory reaction in the host tissue caused by biofragmentable anastomotic ring may explain partially clinical postoperative complications (anastomotic wound infection and/or dehiscence and/or stricture). CONCLUSIONS: In conclusion, the choice of suture materials should be based not only on the mechanical properties, but also on their biological interactions between host and suture materials and on the evaluation of their effective cost/benefit.

Laparoscopic management of benign solid and cystic lesions of the liver.

OBJECTIVE: The authors present their experience in the laparoscopic management of benign liver disease. The aim of the study is to analyze technical feasibility and evaluate immediate and long-term outcome. SUMMARY BACKGROUND DATA: Indications for the laparoscopic management of varied abdominal conditions have evolved. Although the minimally invasive treatment of liver cysts has been reported, the laparoscopic approach to other liver lesions remains undefined. METHODS: Between September 1990 and October 1997, 43 patients underwent laparoscopic liver surgery. There were two groups of benign lesions: cysts (n = 31) and solid tumors (n = 12). Indications were solitary giant liver cysts (n = 16), polycystic liver disease (n = 9), hydatid cyst (n = 6), focal nodular hyperplasia (n = 3), and adenoma (n = 9). Only solid tumors, hydatid cysts, and patients with polycystic disease and large dominant cysts located in anterior liver segments were included. All giant solitary liver cysts were considered for laparoscopy. Patients with cholangitis, cirrhosis, and significant cardiac disease were excluded. Data were collected prospectively. RESULTS: The procedures were completed laparoscopically in 40 patients. Median size was 4 cm for solid nodules and 14 cm for solitary liver cysts. Conversion occurred in three patients (7%), for bleeding (n = 2) and impingement of a solid tumor on the inferior vena cava (n = 1). The median operative time was 179 minutes. All solitary liver cysts were fenestrated in less than 1 hour. There were no deaths. Complications occurred in 6 cases (14.1%). Two hemorrhagic and two infectious complications were noted after management of hydatid cysts. There were no complications after resection of solid tumors. Three patients received transfusions (7%). The median length of stay was 4.7 days. Median follow-up was 30 months. There was no recurrence of solitary liver or hydatid cysts. One patient with polycystic disease had symptomatic recurrent cysts at 6 months requiring laparotomy. CONCLUSION: Laparoscopic liver surgery can be accomplished safely in selected patients with small benign solid tumors located in the anterior liver segments and giant solitary cysts. The laparoscopic management of polycystic liver disease should be reserved for patients with a limited number of large, anteriorly located cysts. Hydatid disease is best treated through an open approach.