Grain carbon isotope composition is a marker for allocation and harvest index in wheat

The natural ¹³ C abundance (δ¹³ C) in plant leaves has been used for decades with great success in agronomy to monitor water-use efficiency and select modern cultivars adapted to dry conditions. However, in wheat, it is also important to find genotypes with high carbon allocation to spikes and grains, and thus with a high harvest index (HI) and/or low carbon losses via respiration. Finding isotope-based markers of carbon partitioning to grains would be extremely useful since isotope analyses are inexpensive and can be performed routinely at high throughput. Here, we took the advantage of a set of field trials made of more than 600 plots with several wheat cultivars and measured agronomic parameters as well as δ¹³ C values in leaves and grains. We find a linear relationship between the apparent isotope discrimination between leaves and grain (denoted as Δδ_corr ), and the respiration use efficiency-to-HI ratio. It means that overall, efficient carbon allocation to grains is associated with a small isotopic difference between leaves and grains. This effect is explained by postphotosynthetic isotope fractionations, and we show that this can be modelled by equations describing the carbon isotope composition in grains along the wheat growth cycle. Our results show that ¹³ C natural abundance in grains could be useful to find genotypes with better carbon allocation properties and assist current wheat breeding technologies.

[Impact of surgery in the management of pancreatic metastases of renal cell cancer]

INTRODUCTION

Incidence of renal cell carcinoma (RCC) is increasing over the 25 last years. Pancreatic metastases of RCC are rare. The aim of this work was to study overall survival of patients operated for pancreatic metastases of RCC in Montpellier cancer institute.

PATIENTS AND METHODS

Between 2000 and 2012, a retrospective monocentric study was performed at Montpellier cancer institute. We evaluated the outcomes of curative pancreatic metastases from renal primary and the impact of targeted therapies.

RESULTS

Thirty-eight patients were treated in our center for pancreatic metastases of RCC. Twelve patients had a curative surgery of metachronous pancreatic metastases. Four patients were without recurrence after pancreatic resection (33.3%). None had adjuvant therapy. Six patients were treated by targeted therapies, because of metastatic progression. Five of 6 died, the sixth evolved with targeted therapies by thyrosine kinase inhibitor. Average deadline between appearance of metastases and death was 89.9 months for operated patients. Average deadline between appearance of c metastases and death was 33.1 months for the others (P=0.004).

CONCLUSION

Surgical treatment of pancreatic metastases should increase life expectancy of patients. Others studies are necessary to prove the impact of targeted therapies in metastatics patients in this indication.

LEVEL OF EVIDENCE

5.

[Endocrine tumor arising in heterotopic gastric pancreas]

We report the case of a 49-year-old caucasian woman, in whom an endocrine tumor arising in gastric heterotopic pancreas was diagnosed. The patient was treated surgically with a gastric wedge resection. Heterotopic pancreas is a benign anatomic condition, probably widely underdiagnosed because usually asymptomatic. The malignant transformation of aberrant pancreas is very rare and almost always in adenocarcinoma. The endocrine tumors developed in heterotopic pancreas are exceedingly rare. Of our knowledge, only four cases have been published and only one case in the gastric location similar to this reported case.

[Spontaneous haemoperitoneum due to a ruptured intra-abdominal varix with cirrhosis: report of two cases]

Spontaneous haemoperitoneum due to ruptured intra abdominal varices with cirrhosis is rare and the diagnosis is generally difficult. Two cases of spontaneous intraperitoneal bleeding due to ruptures varices with cirrhosis are reported. One case is a ruptured portal cavernome and the other one is a ruptured varix of the gastrosplenic ligament. The combination of hypovolemic shock with increasing abdominal girth should impose the diagnosis. This is a surgical emergency and the mortality rate is high.

[Treatment of biliary injuries after laparoscopic cholecystectomy: retrospective study of 27 patients]

Biliary injuries after laparoscopic cholecystectomy are rare but serious. Their mortality rate can reach 9%.

AIM OF THE STUDY

Describe the management of biliary injuries after laparoscopic cholecystectomy in our center.

PATIENTS

Between January 1995 and June 2005, 27 patients (13 women, 14 men) were treated. The mean age was 53 years old (range, 18-92 years). The biliary injuries were common bile duct sections (n=16, 60%), common bile duct stenoses (n=5, 18.5%), biliary fistulas from the cystic duct (n=4, 15%), and biliary fistulas from an aberrant biliary duct (n=2, 7.5%).

RESULTS

Acute cholecystis was present in 40% of cases (n=11). An intraoperative cholangiography was done in 12 patients (44%). The mortality rate was 0%. Of the common bile duct sections, 43% were diagnosed during the cholecystectomy (n=7) or after the cholecystectomy within a mean of 11.2 days (n=9). Common bile duct injuries were treated in 16 cases with hepatojejunostomy and in five cases with an external biliary drain. Fistulas from the cystic duct were diagnosed within a mean 14.8 days. A fistula from an aberrant biliary duct was diagnosed during the cholecystectomy (n=1) or in the second postoperative day (n=1). Fistulas were treated with a clip on the cystic duct (n=2), an external biliary drain (n=1), a biliary endoprosthesis (n=1), and the biliary aberrant duct suture (n=2).

CONCLUSION

Common bile duct injuries are a serious complication because their treatment is a hepaticojejunostomy in 75% of cases.

Laparoscopic surgery and corticoadrenalomas

BACKGROUND

Nowadays, laparoscopic adrenalectomy is the "gold standard" procedure for the treatment of benign lesions. However, the situation is not so clearcut when the issue is laparoscopic excision of malignant adrenal tumors. We present our results of laparoscopic adrenalectomy for treating malignant tumors over the past decade.

METHODS

Between October 1995 and June 2004, 131 consecutive laparoscopic adrenalectomies were performed on 120 patients (11 synchronous bilateral procedures). All patients underwent a standardized investigation protocol during their workup for surgery.

RESULTS

There were only two conversions to laparotomy (1.6%). Complications that occurred during the procedure were limited to six patients (5%). Postoperative 30-days mortality was nil. Postoperative complications occurred in five patients (4.7%) during the first 30 days of recovery. The median hospital stay for all patients was 2.5 days (range = 2-10 days). Twelve patients (9%) had a malignant tumor: nine corticoadrenalomas, one pleomorphic sarcoma, one metastatic deposit from a previously excised colonic cancer, and one malignant pheochromocytoma. At mean followup of 34 months, mean survival time was 42.3 months for corticoadrenalomas that had undergone laparoscopy versus 29.7 months for those who had had a laparotomy. Five of the nine patients are alive and well at a mean of 37 months following surgery. One patient developed pulmonary metastases one year postsurgery; they were responsive to mitotane. Five years later, the same patient had a reoperation for an intra-abdominal retrogastric recurrence of her tumor and continues to do well. Another patient developed pulmonary metastases 22 months following adrenalectomy. Two patients died of metastatic intra-abdominal disease 20 and 7 months postsurgery.

CONCLUSION

When laparoscopic surgery is to used for cancer treatment, caution is the rule to maintain the primary objective of securing a survival rate at least as high as that for open surgery, without increased risk of recurrence. Considering the results presented within this study, it seems that the laparoscopic removal of a corticoadrenaloma should not worsen the prognosis, provided the surgeon respects the primary rules of oncologic resectional surgery. Any surgical conditions that would preclude the strict application of these criteria are contraindications to a laparoscopic procedure.

[Surgical management of a preaortic paraganglioma: Report of one case]

Paragangliomas (PG) are rare and often diagnosed in the young adult. One case of retroperitoneal preaortic paraganglioma localised between the celiac trunk and the superior mesenteric artery is reported. The management of paraganglioma involves endocrinologists, geneticists and surgeons but the only potentially curative treatment remains surgical resection. Pathology reports can not always discriminate between benign or malignant tumors. Hereditary in paraganglioma occurs in approximately 25% of cases. Genetic investigation is therefore mandatory in all patients with PG. Since the type of genetic mutation is correlated with tumoral aggressiveness, genetic investigation results should be taken into account when a surgical procedure is planned.

Évaluation de la prise en charge des hernies inguinales en chirurgie ambulatoire

AIM

To evaluate the prospects of ambulatory surgery for inguinal hernia.

PATIENTS AND METHODS

From January 1995 to June 2001, 599 operations on inguinal hernias were performed. Patients were composed of 554 men and 45 women. The average age was 58 years (7-95). All patients were examined by their primary doctor on the first and the third day, and by the surgeon on the 10th day.

RESULTS

Four hundred and eighty-one patients were operated on by ambulatory surgery (80.3%). The "Tension-free" technique was carried out among 495 patients (82.6%). Loco-regional anaesthesia was used for 499 patients (83.3%). The postoperative rate of complications was 10.4% (62 patients). Only 201 patients presented postoperative painful symptomatology (33.6%), 341 a discomfort (56.9%), and 57 (10%) experienced no pain. The overall satisfaction rate was 92.9%.

CONCLUSION

Use of the "Tension-free" technique under loco-regional anaesthesia for inguinal hernias allows ambulatory surgery with a low rate of complications and high satisfaction for the patients.

Factors and consequences of conversion in laparoscopic sigmoidectomy for diverticular disease

BACKGROUND

The disadvantages of laparoscopic elective sigmoidectomy for diverticular disease include the risk of conversion to open operation and longer operative time. The aim of this study was to analyse the causes and consequences of conversion in 168 consecutive patients who underwent a laparoscopically assisted colectomy between January 1994 and June 2001.

METHODS

Data were collected prospectively to analyse the causes and consequences of conversion to open surgery in terms of postoperative morbidity and patient recovery.

RESULTS

Postoperative mortality, morbidity, conversion and reoperation rates were zero, 21.4 per cent (n = 36), 14.3 per cent (n = 24) and 3.0 per cent (n = 5) respectively. The reasons for conversion were presence of intraperitoneal adhesions and/or inflammatory pseudotumour (n = 21), an intraoperative diagnosis of sigmoid cancer (n = 1), hypercapnia (n = 1) and abdominal bleeding (n = 1). Three preoperative factors were associated with a significant higher risk of conversion: surgical expertise, the presence of sigmoid stenosis or fistula, and the severity of diverticulitis on pathological examination. Morbidity was no different between laparoscopic sigmoidectomy (30 of 144; 20.8 per cent) and converted procedures (six of 24; 25.0 per cent). Open conversion was associated with a longer operative time and significantly delayed patient recovery and hospital discharge.

CONCLUSION

Surgical experience and severe diverticular disease are predictive factors for conversion in laparoscopic elective sigmoidectomy. Even if necessary, conversion does not increase the morbidity rate.

Is laparoscopic left pancreatic resection justified?

BACKGROUND

We reviewed our experience of laparoscopic left pancreatectomy to establish the feasibility of this approach and the characteristics of the operating procedure.

METHODS

Thirteen patients with a mean age of 60 years were deemed for a left pancreatectomy. Preoperative diagnoses were: nine mucinous cystadenoma and one insulinoma, intraductal mucinous ectasia, chronic pancreatitis with ductal stenosis, and distal pancreatic tumor.

RESULTS

Operative mortality was nil. Two patients required conversion for bleeding from splenic vein injuries leading to a splenectomy in one case. The spleen was preserved in 10 cases. Postoperative course was uneventful in nine cases. Four patients experienced postoperative complications: one pancreatic fistula, two liquid cysts on the pancreatic margin, and one reoperation for bleeding from a trocar port. Length of stay ranged from 5 to 22 days.

CONCLUSION

These preliminary results confirm that in selected cases laparoscopic resection of the left pancreas is feasible and safe.

[Laparoscopic re-establishment of digestive continuity following Hartmann's procedure. Retrospective study of the French Society of Endoscopic Surgery]

STUDY AIM

Reversal of the Hartmann's procedure is associated with a high morbidity. The aim of this study was to evaluate the feasibility and results of laparoscopic reversal of the Hartmann's procedure.

PATIENTS AND METHOD

Thirty eight consecutive patients, mean age 60 +/- 13.5 years were included in this retrospective study. The most common indication for the primary procedure was diverticular disease (70%). The mean time from the primary operation to the reconstruction was 136 +/- 124 days. The stoma was first dissected in 24 patients, allowing introduction of the first port. In the remaining 14 patients a standard umbilical port was inserted. The amount of adhesions was classified as low in 13 patients, mild in 15 patients and severe in 10 patients. All patients had a mechanical anastomosis.

RESULTS

The conversion rate was 15%, due to adhesion problems in 5 patients and for a positive leakage test in one. The morbidity rate was 23.5% including 8 surgical complications. One patient died after post operative peritonitis complicating an anastomic leakage. The average hospital stay was 10 +/- 4.4 days.

CONCLUSION

Our results indicate that laparoscopic reversal after Hartmann's procedure is feasible. The morbidity is lower than after classical open reconstruction. The presence of diffuse peritonitis at the primary operation as well as a short delay before the reconstruction, are important factors of conversion.

Nocardiosis revealed by thyroid abscess in a liver--kidney transplant recipient

Nocardiosis is a life-threatening infection, particularly among immunocompromised patients, which usually affects lungs, skin and central nervous system. We report a case of disseminated nocardiosis revealed by suppurative thyroiditis in a liver-kidney transplant recipient with poor nutritional status at the time of infection. Nocardia Asteroides was isolated from fine-needle aspiration material of the thyroid abscess. Clinical manifestations resolved after surgical drainage of the thyroid abscess, prolonged antibiotherapy and diminution of immunosuppressive regimen. Clinicians should be aware of this entity, as Nocardia Asteroides may need more than 5 days of culture to be isolated.

Neoadjuvant tamoxifen for operable breast cancer: a need for phase III studies?

We conducted a case-control study to analyze the effect of neoadjuvant tamoxifen on steroid receptors and histologic grade and to evaluate the feasibility of phase III studies in operable breast cancer. Between 1987 and 1990, 107 patients without clinical metastases who had had no chemotherapy preoperatively, were treated preoperatively with 20 mg/day of tamoxifen for 3 weeks. Of them, 92 were matched with controls for age at diagnosis, year of diagnosis, presence or absence of lymph node involvement, and preoperative radiotherapy. The percentage of ER1 tumors (P = .03) and the mean and median ER levels (P<.001 for both) were lower in the tamoxifen group than in the control group. In six patients analyzed longitudinally, the mean ER decreased from 52 to 19 fmol/mg protein. The difference in relapse-free survival between the two groups was not significant (mean follow-up 87 months). This study suggests a decrease in ER content in patients treated with neoadjuvant tamoxifen. This change may thus be taken into account when ER determination is performed after tamoxifen therapy is started. Further randomized trials should determine whether patients with operable breast cancer benefit from neoadjuvant tamoxifen treatment.

Liver iron excess in patients with hepatocellular carcinoma developed on viral C cirrhosis

BACKGROUND

Liver iron deposits are frequent in viral C cirrhotic patients but their role is not well defined.

AIMS

To investigate the effect of liver iron excess on the prevalence of hepatocellular carcinoma (HCC) in patients with viral C cirrhosis.

METHODS

Hepatic iron was evaluated retrospectively using a semiquantitative method in liver biopsies of 104 viral C cirrhotic patients, 48 with HCC and 56 controls (HCC free). Corrected total iron score (0-60) was defined by the sum of three scores: hepatocytic iron score (0-36), sinusoidal iron score (0-12), and portal iron score (0-12), multiplied by 3/3, 2/3, or 1/3 according to the heterogeneous iron localisation in the nodules.

RESULTS

After adjustment for known risk factors for HCC, regression analysis showed that iron deposits (corrected total iron score >0) were more frequent in HCC patients than in controls (odds ratio 4.94; 95% confidence interval 1.59-15. 32; p=0.0056). The median of corrected total iron score was significantly higher in HCC patients than in controls (odds ratio 1. 092; 95% confidence interval 1.01-1.13; p=0.021). This liver iron overload was sinusoidal (odds ratio 5.2; 95% confidence interval 1. 82-15.11; p=0.0022).

CONCLUSIONS

Liver iron deposition was more frequent and more important in viral C cirrhotic patients with HCC than in HCC free controls. Liver iron overload seems to contribute to the development of HCC in patients with viral C cirrhosis.

[Treatment of common bile duct stones with laparoscopy. Retrospective multicenter study with 612 patients]

OBJECTIVE

To analyse retrospectively the results of one-stage laparoscopic treatment for common bile duct stones in 19 surgical centers in France.

PATIENTS

From January 1991 to July 1996, 612 patients with choledocholithiasis underwent laparoscopic treatment.

RESULTS

Overall duct clearance was obtained in 489 of the 612 patients (80%): through the cystic duct in 222 of 380 patients (58.4%), by secondary choledochotomy (after unsuccessful transcystic duct extraction) in 77 of 96 (80%), and in 190 of 232 (82 %) by primary choledochotomy. The overall duct clearance rate increased from 65% in 1991 to 84% in 1996. The use of the choledochotomy approach increased from 43% in 1991 to 69% in 1996 (P<0.01), due to a substantial increase in primary choledochotomy. In contrast, the use of the transcystic approach decreased from 57% to 31% (P<0.01). The mean time for surgery was shorter for cystic duct exploration than for primary choledochotomy (101+/-51 vs. 155+/-62 min, P<0.0001). The mean hospital stay decreased from 7.7+/-3.6 days in 1991 to 4.1+/-2 days in 1996 (P<0.001). The main biliary complications were related to biliary drainage (2,8%) and retained stones (3.1%).

CONCLUSION

This study confirms that laparoscopy is a good alternative with a low complication rate, a short hospital stay, and is an effective and safe option for the management of common bile duct stones.

[Elective laparoscopic colectomy for sigmoid diverticulitis. Prospective study of 56 cases]

OBJECTIVE

The aim of this prospective study was to assess the feasibility and postoperative advantages of the laparoscopic-assisted elective colectomy for diverticular disease.

PATIENTS AND METHODS

From january 1989 to december 1997, among the 114 patients electively operated on for diverticulitis, 56 patients were treated by laparoscopic approach. Evaluated parameters included: gender, age, weight, size, ASA score, operating time, duration of hospital stay, of analgesic treatment, and of postoperative ileus, morbidity and mortality rate.

RESULTS

The study group consisted of 35 women and 21 men. Mean age was 59 years (34-81 years); 29 patients were ASA 1 and 27 ASA 2. Overall postoperative mortality rate was 0% and morbidity rate 16% (n = 9). There were no complications directly related to laparoscopic technique. The conversion rate was 14% (n = 8). Mean operating time was 300 min (200-600 min). Mean duration of postoperative ileus was 2.4 days. Mean duration of hospital stay was 9.4 days.

CONCLUSION

This study demonstrates the feasibility of elective laparoscopic-assisted colonic resection for diverticular disease in more than 80% of cases with a postoperative morbidity and mortality rate comparable to those of conventional surgery.

Natural killer cell and alphabeta and gammadelta lymphocyte traffic into the liver graft immediately after liver transplantation

BACKGROUND

The persistence and migration of donor leukocytes has been well established, but cellular kinetics immediately after revascularization and the potential relevance of these different lymphocyte populations to spontaneous tolerance remain unclear. During the early hours of revascularization, there is a transitory "congestion" of the liver graft, which is evidence of an early phase that we have termed "first cellular contact."

METHODS

We have carried out by flow cytometry a prospective comparative study of the peak kinetics of lymphocyte subpopulations contained in: (a) peripheral blood and liver grafts at the time of multi-organ extraction from 14 brain-dead donors, (b) recipient peripheral blood before transplantation, and (c) recipient peripheral blood and liver grafts after (t=2 h) declamping and vascularization of the liver graft.

RESULTS

Before transplantation, the liver grafts contained large numbers of natural killer (NK) and NK-like cells with early lymphocyte activation. Immediately after revascularization, there was an influx of recipient NK and NK-like cells into the liver.

CONCLUSIONS

NK and CD3+CD56+ (NK-like) cells flooding into the liver graft immediately after revascularization could rapidly destroy allogeneic cells. However, spontaneous tolerance and the persistence of donor lymphocytes after orthotopic liver transplant could be a result of donor TCRalphabeta NK1.1 liver graft lymphocytes, which may be involved in the destruction of CD8+ T lymphocytes that would have received the apoptosis signal, and to NK and NK-like cell inhibition via inhibitory NK receptors. The decrease in gammadelta T lymphocytes in the two compartments suggests a mechanism of recirculation and capture in other lymphoid organs.

Prevalence and mechanisms of small intestinal obstruction following laparoscopic abdominal surgery: a retrospective multicenter study. French Association for Surgical Research

HYPOTHESIS

The prevalence and mechanisms of intestinal obstruction following laparoscopic abdominal surgery have not been studied extensively.

DESIGN

Retrospective review of cases of intestinal obstruction after laparoscopic surgery.

SETTING

Sixteen surgical units performing laparoscopy in France.

PATIENTS

Twenty-four patients with intestinal obstruction.

MAIN OUTCOME MEASURES

Prevalence values and descriptive data.

RESULTS

The 3 most frequent primary procedures responsible for intestinal obstruction were cholecystectomy (10 cases), transperitoneal hernia repair (5 cases), and appendectomy (4 cases). Prevalences of early postoperative intestinal obstruction after these procedures were 0.11%, 2.5%, and 0.16%, respectively. Intestinal obstruction was due to adhesions or fibrotic bands in 12 cases and to intestinal incarceration in 11 cases. Obstruction was located at the trocar site in 13 cases (9 incarcerations and 4 adhesions), mainly at the umbilicus, and in the operative field in 10 cases (2 incarcerations in a wall defect after transperitoneal inguinal hernia repair, 4 adhesions, and 4 fibrotic bands). The small intestine was involved in 23 of 24 cases; the other was due to cecal volvulus following unrecognized intestinal malrotation. Intestinal obstruction was treated by laparoscopic adhesiolysis in 6 patients and by laparotomy in 18 patients, 6 of whom required small intestine resection. Three postoperative complications but no deaths occurred.

CONCLUSION

Intestinal obstruction following laparoscopic abdominal surgery can occur irrespective of the type of operation; the prevalence is as high as (cholecystectomy and appendectomy) or even higher than (transperitoneal hernia repair) that seen in open procedures.

Comparison of intravenous or epidural patient-controlled analgesia in the elderly after major abdominal surgery

BACKGROUND

Patient-controlled analgesia (PCA) with intravenous morphine and patient-controlled epidural analgesia (PCEA), using an opioid either alone or in combination with a local anesthetic, are two major advances in the management of pain after major surgery. However, these techniques have been evaluated poorly in elderly people. This prospective, randomized study compared the effectiveness on postoperative pain and safety of PCEA and PCA after major abdominal surgery in the elderly patient.

METHODS

Seventy patients older than 70 yr of age and undergoing major abdominal surgery were assigned randomly to receive either combined epidural analgesia and general anesthesia followed by postoperative PCEA, using a mixture of 0.125% bupivacaine and sufentanil (PCEA group), or general anesthesia followed by PCA with intravenous morphine (PCA group). Pain intensity was tested three times daily using a visual analog scale. Postoperative evaluation included mental status, cardiorespiratory and gastrointestinal functions, and patient satisfaction scores.

RESULTS

Pain relief was better at rest (P = 0.001) and after coughing (P = 0.002) in the PCEA group during the 5 postoperative days. Satisfaction scores were better in the PCEA group. Although incidence of delirium was comparable in the PCA and PCEA groups (24% vs. 26%, respectively), mental status was improved on the fourth and fifth postoperative days in the PCEA group. The PCEA group recovered bowel function more quickly than did the PCA group. Cardiopulmonary complications were similar in the two groups.

CONCLUSION

After major abdominal surgery in the elderly patient, patient-controlled analgesia, regardless of the route (epidural or parenteral), is effective. The epidural route using local anesthetics and an opioid provides better pain relief and improves mental status and bowel activity.

Specific vascular complications of orthotopic liver transplantation with preservation of the retrohepatic vena cava: review of 1361 cases

OBJECTIVE

The objective of this study was to describe the complications specifically related to orthotopic liver transplantation (OLT) with preservation of the inferior vena cava and to their therapeutic management. This preservation technique has considerably influenced the surgical phases of liver transplantation, increasing hepatectomy time and modifying the number of vascular anastomoses.

METHODS

Our retrospective multicentric study, based on data from 1361 adult patients that had undergone orthotopic liver transplantation with preservation of the inferior vena cava in France between 1991 and 1997, analyzed the concomitant surgical complications. Type of cavo-caval anastomosis performed (piggyback, end-to-side, or side-to-side), use of a temporary portacaval anastomosis, technique-related complications, and mortality, were investigated.

RESULTS

Cavo-caval anastomosis was side-to-side in 50.6% of cases (n=689), piggyback in 42.7% (n=582), and end-to-side in 6.6% (n=90). In total, 882 temporary portacaval anastomosis were carried out. Fifty-five patients presented with one or more complications related to the preservation of the inferior vena cava technique; i.e., overall morbidity was 4.1% (55/1361). Overall mortality was 0.7% (10/1361). Mortality rate for patients who presented with surgical complication was 18%. A total of 64 complications were recorded: 57 (89%) were in the perioperative or immediate postoperative period and 7 (11%) were postoperative.

CONCLUSIONS

These retrospective, descriptive results show significant advantages in favor of side-to-side anastomosis in terms of vascular complications. Certain factors should be evaluated specifically at pretransplant assessment to prevent certain serious complications; principally, these are anatomic factors of the recipient (inferior vena cava included in segment I, anatomic abnormalities of the inferior vena cava) and graft size. Depending on these factors, surgeons must be able to adapt the orthotopic liver transplantation, either before or during orthotopic liver transplantation, preferring the standard technique.

Alcoholic cirrhosis is a good indication for liver transplantation, even for cases of recidivism

BACKGROUND/AIMS

Alcoholic cirrhosis remains a controversial indication for liver transplantation, mainly because of ethical considerations related to the shortage of donor livers. The aim of this study was to review experience to date, focusing on survival rates and complications, and the effect of alcohol relapse on outcome and alterations in marital and socioprofessional status.

METHODS

The results for 53 patients transplanted for alcoholic cirrhosis between 1989 and 1994 were compared with those for 48 patients transplanted for non-alcoholic liver disease. The following variables were analysed: survival, rejection, infection, cancer, retransplantation, employment and marital status, alcoholic recurrence. The same variables were compared between alcohol relapsers and non-relapsers.

RESULTS

Recovery of employment was the only significantly different variable between alcoholic (30%) and non-alcoholic patients (60%). Two factors influenced survival in the absence of alcohol recidivism: age and abstinence before transplantation. For all other variables, there were no differences between alcoholic and non-alcoholic patients, and, within the alcoholic group, between relapsers and non-relapsers. The recidivism rate was 32%.

CONCLUSION

The data indicate that liver transplantation is justified for alcoholic cirrhosis, even in cases of recidivism, which did no affect survival and compliance with the immunosuppressive regimen. These good results should help in educating the general population about alcoholic disease.

Evidence for the presence of a functional pregnane X receptor response element in the CYP3A7 promoter gene

Pregnane X Receptor (PXR) has been recently shown to regulate the inducible expression of CYP3A genes in response to xenobiotics and steroids. PXR forms a heterodimer with the retinoic acid receptor (RXR) and this complex binds to and transactivates an 18bp region containing two everted repeats TGA(A/C)CT separated by 6 nucleotides (ER6) and located at approximately -150 in the CYP3A4 promoter. In this work we have isolated and sequenced the proximal 5'-flanking region of CYP3A7 from two different human genomic libraries. In contrast to a previously reported sequence (Itoh et al., 1992), we did not observe any mutation in the 3'-half of the CYP3A7 ER6 element. Using electrophoretic mobility shift assays and cotransfection experiments we show that this element is able to bind the PXR:RXR complex and transactivates the expression of a down stream promoter in response to rifampicin, clotrimazole, and RU-486, three compounds known to specifically activate the human PXR. This is consistent with the fact that CYP3A7 mRNA is inducible in several primary cultures of human hepatocytes from different patients, as well as in two hepatocarcinoma cell lines HuH7 and HepG2, in response to these compounds. In contrast to a previous report (Blumberg et al., 1998), based on the sequence published by Itoh et al., we conclude that CYP3A7, like CYP3A4, is inducible in response to xenobiotics and presumably in a large proportion of the population.

Delayed gastric emptying after pancreaticoduodenectomy and pancreaticogastrostomy

OBJECTIVE

To find out which factors influence the development of delayed gastric emptying (DGE) after pancreaticoduodenectomy with pancreaticogastrostomy.

DESIGN

Prospective clinical study.

SETTING

University hospital, France.

SUBJECTS

88 patients of 103 consecutive patients who had had pancreaticoduodenectomies, November 1991-November 1997.

INTERVENTIONS

Whipple resection, and parenteral and enteral nutrition.

MAIN OUTCOME MEASURES

Mortality, morbidity, and development of DGE (defined as the need for a postoperative nasogastric tube for 10 days or longer).

RESULTS

One patient died, and 44 developed postoperative complications. 36 patients (41%) developed DGE in 21 of whom (58%, 24% of the total) it was in isolation, with no other complication; and 52 (59%) did not. There were significant differences between those who developed DGE and those who did not: 30 men (83%) compared with 6 women (17%) developed DGE compared with 32 (62%) and 20 (38%) (p = 0.03;); 15 (42%) developed a complication as well as DGE compared with 8 (15%) (p = 0.005); 10(28%) who developed DGE required reoperation compared with 4(8%) (p = 0.011); mean (SD) hospital stay was 30(12) days among those with DGE compared with 17 (5) days (p= 0.0001); and their mean (SD) serum protein concentration on day 1 was 46 (1) compared with 51 (7) g/L (p=0.01). Multivariate analysis showed that three factors independently influenced the development of DGE: sex (p = 0.01), the need for reoperation (p = 0.03) and the mean serum protein concentration on day 1 (p = 0.04).

CONCLUSION

Postoperative complication and the need for reoperation remain the most common factors linked to the development of DGE. However, in a quarter of patients DGE was not associated with any postoperative complication.

[Needle-tract seeding after ultrasound-guided puncture of hepatocellular carcinoma. A study of 150 patients]

OBJECTIVES

To study the frequency of tumor seeding after percutaneous biopsy of hepatocellular carcinoma and to evaluate the impact on long-term survival.

METHODS

Records of 150 patients with cirrhosis who underwent ultrasound-guided aspiration biopsy for hepatocellular carcinoma between 1989 and 1996 were reviewed in June 1998. Liver transplantation was performed in 7 patients. One to three needle passes were performed with 18 to 20 gauge needles. Follow-up included regular clinical examinations and ultrasonography or computerized tomography.

RESULTS

Four cases (2.66%) of subcutaneous metastasis were noted at the needle insertion site; none in transplanted patients. All patients had viral cirrhosis, Okuda class I. Nodules were detected 4, 12, 22 and 24 months after biopsy. The second patient is alive 24 months after tumor seeding. For other patients, survival time was 4, 24 and 60 months respectively, without local tumor extension after surgical resection or radiotherapy. During a mean 11.8 months of follow-up, 127 patients died without tumor seeding. Eleven patients are still being followed and have no signs of needle tract implantation of hepatocellular carcinoma (mean follow-up 34.7 months).

CONCLUSION

The prevalence of tumoral seeding after percutaneous biopsy of hepatocellular carcinoma was 2.66%, which is higher than in previous studies. After liver transplantation, no evidence of needle tract seeding was identified. Survival did not seem to be influenced by local evolution.

Hepatitis C virus genotypes and quantification of serum hepatitis C RNA in liver transplant recipients. Relationship with histologic outcome of recurrent hepatitis C

The reasons for wide variations in the severity of recurrent hepatitis C after liver transplantation are unclear. We studied liver transplant recipients to assess the effect of hepatitis C virus (HCV) genotype and HCV RNA quantification on histologic progression of recurrent hepatitis C after transplantation. Twenty-five patients underwent transplantation for HCV cirrhosis and were followed up with virologic and histologic assessments for a mean of 51 months. HCV genotype was determined by line probe assay. HCV RNA was quantitated in serum samples by nested polymerase chain reaction. The HCV genotype 1 was detected in 17 patients and other genotypes in 8. Acute lobular hepatitis developed in 17 patients 162 days posttransplantation on average. Long-term biopsy specimens (mean, 51 months after the date of liver transplantation; range, 24-86 months) showed chronic hepatitis in 19 patients (mild, 5; moderate, 9; and severe, 5, 2 with extensive scarring). The serum alanine aminotransferase level was correlated with hepatocyte necrosis (piecemeal and lobular) but not with portal inflammation or fibrosis. Patients infected with genotype 1 had a higher Knodell score, and the 5 patients with severe hepatitis C all were infected with genotype 1. HCV RNA levels were significantly higher in patients with genotype 1 than in patients with other genotypes, as were the severity of histologic recurrence and levels of viral replication.

Abdominal laparoscopic approach for thoracic epiphrenic diverticulum

The true incidence of epiphrenic esophageal diverticulum is unknown. Traditionally, diverticulectomy via a left thoracic approach has represented the gold standard. Trans-hiatal esophageal dissection under laparoscopy is feasible, but has not, to our knowledge, been applied before in the treatment of epiphrenic esophageal diverticulum.

[Hemodynamic monitoring using esophageal Doppler ultrasonography during laparoscopic cholecystectomy]

PURPOSE

To evaluate the use of a 4-mHz continuous wave esophageal Doppler monitor in the hemodynamic management of 48 ASA I to III patients undergoing laparoscopic cholecystectomy.

METHODS

General anesthesia was induced with fentanyl and propofol, maintained with N20 N20/02 and muscle relaxation was provided with atracurium. The lungs were mechanically ventilated. Non invasive arterial blood pressure, heart rate, capnography, arterial blood gas were monitored during CO2 pneumoperitoneum at 15-mmHg. Using the velocity waveform of descending aortic blood flow, the Doppler device estimated changes in cardiac output and systemic vascular resistances.

RESULTS

Peritoneal insufflation resulted in a mean 19% decrease in cardiac output (range -49 to +5%; P < 0.05) and a mean 48% increased in systemic vascular resistances (range -7 to +101%; P < 0.01). There was no relationship between changes in cardiac output and mean arterial pressure or PETCO2. The esophageal Doppler provided, in two patients, details of hypertensive peaks (mean arterial pressure > 140 mmHg) which responded to administration of nicardipine.

CONCLUSION

The Esophageal Doppler provided an easy-to-handle and non invasive tool to monitor changes in cardiac output during laparoscopic cholecystectomy. However, further comparison with a thermodilution cardiac output technique is required.

Management of intraductal papillary mucinous tumours of the pancreas

OBJECTIVE

To focus attention on the management and outcome of patients with intraductal papillary mucinous tumours of the pancreas.

DESIGN

Retrospective study and analysis of published reports.

SETTING

University hospital, France.

SUBJECTS

111 patients (101 published cases and our own 10 cases) divided in two groups: the first including malignant tumours (n = 46), and the second group benign or in situ tumours (n = 61). In 4 patients the type of tumour was not known.

MAIN OUTCOME MEASURE

Resectability, mortality and recurrence.

RESULTS

More men had benign or in situ tumours [48/61 (79%) compared with 28/46 (61%), p = 0.054]. Pancreatitis was more common among benign than malignant tumours [34/61 (58%) compared with 21/46 (46%), p = 0.33]. In group I, 39 patients had diabetes. A total of 107 patients were operated on: pancreaticoduodenectomy (n = 54, 50%), distal pancreatectomy (n = 25, 23%), total pancreatectomy (n = 4,4%), bypass (n = 2,2%). The type of resection was not mentioned in 22 records (21%). Four patients were not operated on because of their poor general condition. The resectability rate was 98% (105/107). Eleven patients had died at the time of publication. Hospital mortality rate was 3% (n = 3), mainly because 2 of the 4 who had total pancreatectomy died. With a median follow-up of 37 months, recurrence was 5% (n = 5).

CONCLUSION

Intraductal papillary mucinous tumours of the pancreas are well known distinctive pancreatic tumours that are usually intraductal but may develop into invasive carcinoma. They should be resected, and have a good prognosis and low recurrence rate.

In vitro infection of adult normal human hepatocytes in primary culture by hepatitis C virus

In vitro infection of adult normal human hepatocytes in primary culture has been performed for investigating the replication cycle of hepatitis C virus (HCV) in differentiated cells. Hepatocytes were prepared from liver tissue resected from donors who tested negative for HCV, and inoculation was performed 3 days after plating with 33 HCV serum samples of different virus load and genotype. The presence of intracellular HCV RNA, detected by a strand-specific rTth RT-PCR assay, was used as evidence of infection. A kinetics analysis of HCV replication revealed that intracellular negative-strand RNA appeared at day 1 post-infection with a maximum level at days 3 and 5, followed by a decrease until day 14. At day 5, we estimated that the copy level of viral RNA was amplified at least 15-fold in infected cells. The level of intracellular HCV RNA in response to different serum samples was reproducible from one hepatocyte culture to another, suggesting that there is no inter-individual variability in the susceptibility of hepatocytes to HCV infection. These findings indicate that adult human hepatocytes in primary culture retain their susceptibility to in vitro HCV infection and support HCV RNA replication. This model should represent a valuable tool for the study of initial steps of the HCV replication cycle and for the evaluation of antiviral molecules.

Diaphragmatic and subcutaneous seeding of hepatocellular carcinoma following fine-needle aspiration biopsy

AIMS/BACKGROUND

We report the discovery of associated metastatic subcutaneous and metastatic diaphragmatic nodules on the needle track after fine-needle biopsy aspiration under echography, which has not yet been reported in the literature.

METHODS

A 35-year-old man with non-replicating hepatitis B virus presented with a tumor that suggested hepatocarcinoma with cirrhosis. A diagnostic needle biopsy was carried out before surgery. Twelve months later, he presented with a series of four continuous metastatic diaphragmatic nodules on the inner wall lining the needle track. Surgery was performed, followed by external radiation (40 Gy).

CONCLUSIONS

The risk of seeding following fine-needle biopsy aspiration of hepatocellular carcinoma can no longer be considered negligable. The real risk is probably underestimated. Even for biopsy of lesions localized to the inferior part of the liver, diaphragmatic seeding is possible. This seeding necessitates surgical resection, increasing the therapeutic morbidity of hepatocellular carcinomas. We believe that in cases where investigation of a small hepatic tumor suggests a hepatocellular carcinoma that could be resected, or for candidate patients for liver transplantation. one should not puncture the tumor. If this diagnostic biopsy is essential, then the needle track could be resected upon surgery, after cutaneous external tattooing.

Activated sub-populations of lymphocytes and natural killer cells in normal liver and liver grafts before transplantation

AIMS/BACKGROUND

The anatomic structure of the liver suggests that it is a place of intense trafficking between intra-hepatic and peripheral blood compartment leukocytes. Furthermore, the liver contains a large number of passenger leukocytes that may play a role in the appearance of donor-type microchimerism after transplantation. In this study, we aimed to define the principal lymphocyte sub-populations contained in donor peripheral blood and liver grafts and in normal liver removed during minimally invasive surgery.

METHODS

Liver biopsies were taken at the time of vascular clampage during liver extraction from donors in a brain dead state (GI: n=14). Normal liver biopsies were removed during minimaly invasive surgery (GII: n= 10).

RESULTS

We observed evidence of the presence of lymphocytic activation associated with the two major CD8+ lymphocyte and natural killer (NK) cell populations in the two groups, with a significant increase in TCRgammadelta-bearing lymphocyte receptors between normal liver and the liver graft.

CONCLUSIONS

The presence of activated leukocytes in the graft could have a fundamental role in induction of peripheral tolerance. This activation could be the result of a basic immunological response linked to the interaction of T cells and NK cells, and of secondary activation due to stress and the conditions necessary for organ removal from donors in a brain dead state.

Results of pancreatogastrostomy after pancreatoduodenectomy in 160 consecutive patients

BACKGROUND

The advantages of pancreatogastrostomy over pancreatojejunostomy after pancreaticoduodenectomy are still debated. This study analyses the results of pancreatogastrostomy to identify factors that could influence immediate outcome.

METHODS

During a 10-year period, 160 consecutive patients underwent a pancreatogastrostomy. There were 109 men (68 per cent) and 51 women (32 per cent) with a mean(s.d.) age of 59(10) (range 22-82) years; 27 patients were older than 70 years. The following parameters were assessed: mortality rate, morbidity, reasons for reoperation, length of hospital stay, duration of nasogastric tube and drainage.

RESULTS

Hospital mortality rate was 3 per cent; overall morbidity rate was 30 per cent. The reoperation rate was 12 per cent, mainly because of bleeding at the pancreatic margin. Delayed gastric emptying occurred in 36 patients. The overall rate of pancreatic fistula was 2.5 per cent. Age, sex, indications for pancreatoduodenectomy, and the texture of the pancreatic remnant did not influence the occurrence of pancreatic fistula or delayed gastric emptying.

CONCLUSION

This study confirmed that pancreatogastrostomy is a safe procedure with low mortality and morbidity rates.

Experimental assessment of the risk of tumor recurrence after laparoscopic surgery

BACKGROUND

The aim of this experimental study was to evaluate the risk of tumor recurrence after laparoscopic cecal resection (LCR) of colonic carcinoma in the rat.

METHODS

The experimental cancer consisted of one million cells (DHK/K12), incorporated in an extracellular matrix, placed and secured to the cecal serosa in 110 BD9 rats. Four weeks later, all animals were reoperated through a laparotomy to control tumor growth, and animals with diffuse carcinomatosis were excluded. Eligible animals were randomized either to laparoscopic cecal resection (group LCR, n = 10), to open resection (group OCR, n = 13), or to a control group without resection (group C, n = 13). Resection was always considered as macrocopically complete. All animals were killed 4 weeks after the resection to determine the tumor recurrence and quantify carcinomatosis.

RESULTS

We noted diffuse carcinomatosis in 70% of rats in groups C and LCR versus 23% in group OCR (p = 0.038). For tumors noted as S- (not extending outside the serosa), diffuse carcinomatosis was observed in all animals of group C (3 of 3), in 6 of 8 in group LCR, and 0 of 6 in group OCR (p = 0.004). The rate of port site or incisional metastases was not significantly different between groups.

CONCLUSIONS

These preliminary results demonstrated the deleterious impact of the laparoscopy for resection of large bowel malignancy. LCR increased significantly the incidence of a diffuse carcinomatosis even when performed for locally noninvasive tumors (S-).

Prevalence of monoclonal immunoglobulins after liver transplantation: relationship with posttransplant lymphoproliferative disorders

BACKGROUND

A high incidence of serum monoclonal immunoglobulins (mIgs) has been described after solid organ transplantation. For transplant recipients, the prevalence of posttransplant lymphoproliferative disorders (PTLDs) has been reported to be between 2% and 6%. The relationship between the finding of serum mIg in transplant recipients and the subsequent development of PTLDs is not clearly documented.

METHODS

We retrospectively analyzed all cases of mIg and PTLD that occurred in 86 liver transplant recipients who survived more than 3 months. Patients were characterized by protein electrophoresis, immunofixation electrophoresis, pre- and post-liver transplantation Epstein-Barr virus (EBV) serology, EBV presence in lymphoproliferative tissues by in situ hybridization, type of infection episodes, rejection episodes, and immunosuppressive treatment.

RESULTS

Thirty-eight patients (44%) had abnormal immunofixation electrophoresis with an electrophoretic Ig peak. Twelve patients had a polyclonal Ig peak, and 26 patients had mIgs (30%). These 26 patients were divided into two groups: 13 patients had a transient mIg peak with a mean delay for normalization of electrophoresis of 2 months, and 13 patients had a permanent mIg peak. No correlation could be demonstrated between the appearance of abnormal banding and indications for transplantation, age of patients, and acute rejection rate. There was a strong correlation between occurrence of viral infections and presence of permanent mIg. Three patients with permanent mIg (23%) developed PTLD and died.

CONCLUSIONS

We concluded that the prevalence of mIg after liver transplantation was 30%. Viral infections increase the risk of developing mIg. Persistence of mIg beyond 7 months may be regarded as prelymphomas necessitating a careful follow-up in these patients.

Long-term primary cultures of adult human hepatocytes

In this work we have investigated a system of long-term primary cultures of adult human hepatocytes which, in contrast to those previously described, has the advantage of requiring neither the use of additive cells as in co-cultures, nor of matrix component preparations like Matrigel or collagen sandwich. This system has been used previously for long-term cultures of hepatocytes from young baboon, and some modifications have been introduced here to take into account the specificity of adult human hepatocytes. In this system, hepatocytes are plated at confluence on collagen-coated dishes and cultured in a serum-free medium consisting of Williams'E supplemented with hormones and growth factors. Proteins secreted specifically by the liver, including albumin, alpha-1 antitrypsin, plasminogen, fibrinogen, lipoproteins ApoA1 and ApoB100, have been quantified in the extracellular medium as a function of time, either by immunoblot or ELISA. In addition, the expression and inducibility of CYP proteins of the CYP1, CYP2 and CYP3 families in response to their prototypical inducers including 2,3,7,8-tetrachlorodibenzo(p)dioxin and rifampicin, have been evaluated by immunoblot analysis of microsomes or cell lysates. Moreover, the oxidative metabolism of cyclosporin A, a monoxygenase activity depending on CYP3A4, has been monitored directly on the cultured cells by HPLC analysis of extracellular medium. Our results show that, under these culture conditions, adult human hepatocytes retain these phenotypical characteristics for at least 35 days. This system meets the requirements for use as a model for screening CYP protein inducers.

Hepatitis C virus genotypes and quantitation of serum hepatitis C virus RNA in liver transplant recipients: relationship with severity of histological recurrence and implications in the pathogenesis of HCV infection

The reasons for the wide variation of incidence and severity of recurrent hepatitis C after liver transplantation are not clear. We have studied liver transplant recipients to assess the impact of hepatitis C virus (HCV) genotype and HCV RNA quantification on HCV recurrence after transplantation. Twenty-two patients received transplants for HCV cirrhosis and were followed up with virological and histological assessments. Mean follow-up was 39 months. HCV genotype was determined with line probe assay (Inno-Lipa). HCV RNA quantity was determined in serum samples by use of polymerase chain reaction nested assay. HCV genotype 1 was detected in 13 patients and other genotypes in 9. Histological recurrence rates were 69% in patients with genotype 1 and 66% in patients with other genotypes. All cases of severe histological injury (chronic active hepatitis or cirrhosis) were observed in patients with genotype 1. HCV RNA quantity was significantly higher in patients with genotype 1 (mean, 2.023 x 10(3) copies/mL) than in patients with other genotypes (mean, 27,403 copies/mL). In conclusion, the severity of histological recurrence after liver transplantation for HCV disease was higher in patients infected by HCV genotype 1 than in those infected with other genotypes. The levels of viral replication were higher in patients with HCV genotype 1 than in those with other genotypes.

Liver resection or transplantation for hepatocellular carcinoma? Retrospective analysis of 215 patients with cirrhosis

BACKGROUND/AIMS

Currently, surgical treatment of hepatocellular carcinoma in patients with cirrhosis is not clearly defined. The objective of this study was, in patients with cirrhosis with hepatocellular carcinoma, to compare liver resection to transplantation assessed by patient survival and to determine whether the tumor recurrence might be influenced by prognostic factors.

METHODS

We have gathered all the available data from six French Medical Universities, for 215 patients with cirrhosis with hepatocellular carcinoma surgically treated either by liver resection (102) or by transplantation (113).

RESULTS

The overall 5-year survival rate was similar in the transplantation group and in the resection group (32% vs. 31%, p=0.7). However, the 5-year survival rate without recurrence was higher in the transplantation group than in the resection group (60% vs. 14%, p<0.001). Three independent prognostic factors influenced significantly the survival without recurrence: the surgical treatment by transplantation (p<0.001), the number of tumors (p<0.01) and the tumor size (p<0.001). With these factors we defined a prognostic index (Ip) which allowed assessment of the probability of survival without recurrence: Ip= (Xie. x 1.41)+(Nbr T. x 0.19)+(Size TV. x 0.16); Xie=surgical treatment (Xie=0 if transplantation, Xie=1 if resection), Nbr.T. and Size TV.=number of tumors and size of the most voluminous tumor, respectively, according to the histologic study.

CONCLUSIONS

These results and this prognostic index are encouraging for liver transplantation as treatment of hepatocellular carcinoma in selected patients with cirrhosis.

Effect of cell density and epidermal growth factor on the inducible expression of CYP3A and CYP1A genes in human hepatocytes in primary culture

The influence of cell density and epidermal growth factor (EGF) on the expression and inducibility of cytochrome P450 (CYP) genes of the CYP3A and CYP1A families in adult human hepatocytes in primary culture has been evaluated. Only when cultured at subconfluence and in the presence of EGF did hepatocytes exhibit a proliferative response, assessed by measuring DNA synthesis and cyclin A accumulation. In the absence of EGF, the accumulation of CYP3A4 and CYP1A2 messenger RNAs (mRNAs) in response to their respective inducers (rifampicin and dioxin) was dramatically decreased in subconfluent culture with respect to confluent cultures. The presence of EGF only slightly decreased the accumulation of these mRNAs in both confluent and subconfluent cultures. The accumulation of CYP2D6 and CYP2E1 proteins, which are constitutively expressed in confluent cultures, and the production of fibrinogen and apolipoprotein (Apo) B100 exhibited similar behavior, while nicotinamide adenine dinucleotide phosphate cytochrome c reductase activity was affected neither by cell density nor by EGF. In contrast, the accumulation of CYP1A1 mRNA in response to dioxin was similar in confluent and subconfluent cultures, irrespective of the presence of EGF. Interestingly, CYP3A7, a gene that is preferentially expressed in the fetal liver, was expressed constitutively neither in confluent nor in subconfluent cultures, irrespective of the presence of EGF. It is concluded that the loss of cell-cell contacts rather than the proliferative status of cells per se is responsible for the dramatic decrease in the expression of CYP genes, normally expressed in the adult human liver.

Lipid-mediated transfection of normal adult human hepatocytes in primary culture

The aim of this work was to develop a procedure for the lipid-mediated transfection of DNA into normal adult human hepatocytes in culture. Cells were plated in a serum-free culture medium at various cell densities, on plastic or collagen-coated dishes, both in the absence and in the presence of epidermal growth factor (EGF). The cells were incubated for various periods of time with mixtures of DNA-lipofectin or DNA-3 beta[N-(N',N'-dimethylaminoethane)-carbamoyl] cholesterol (DC-chol) liposomes, and the efficiency of transfection was assessed by measuring the activity of reporter genes, beta-galactosidase or chloramphenicol acetyl-transferase (CAT). For comparison, similar experiments were carried out with human cell lines including HepG2, Caco-2, and WRL68. The efficiency of transfection (in percentage of cells) was not significantly different after transfection with lipofectin or DC-chol and comprised between 0.04 and 1.7% (extreme values) for different cultures. The efficiency of transfection decreased as the age or density of the culture increased and increased in cultures treated with EGF. Direct measurement of the rate of DNA synthesis suggested that the efficiency of transfection was related to the number of cells entering the S phase. Under the same conditions, the efficiency of transfection was one to two orders of magnitude greater in the three cell lines. A plasmid harboring 660 bp of the 5'-flanking region of CYP1A1 (containing two xenobiotic enhancer elements) fused upstream of the promoter of thymidine kinase and the CAT reporter gene was constructed. When this plasmid was transfected in human hepatocytes, CAT activity was induced as expected. We conclude that normal adult human hepatocytes can be transfected with exogenous DNA and that the transfected construct is regulated in the manner expected from in vivo studies.