Preliminary experience with the use of an autologous platelet-rich fibrin membrane for urethroplasty coverage in distal hypospadias surgery

OBJECTIVE

Platelet-rich fibrin (PRF) has been shown to have structural and biological properties that promote tissue healing. This prospective study evaluated the feasibility, safety, and efficiency of using autologous PRF membrane for urethroplasty coverage in distal hypospadias.

MATERIALS AND METHODS

We prospectively included 33 patients with distal hypospadias operated on between June 2010 and September 2011. Urethroplasties were performed using the Duplay technique. During surgery, 5-10 ml of patient's blood was collected and immediately centrifuged. A PRF clot was transformed into a dense fibrin membrane with a particular cell content and architecture. This membrane was applied and sutured over the urethroplasty. The perioperative course and complications were recorded. Outcomes were compared with those in a control group of children undergoing the same procedure, but with another mean of coverage.

RESULTS

With a median follow-up of 8 months (range, 6-18 months), urethral fistula occurred in 2/33 patients. No other complication was noted. No complication related to the blood sampling was reported. There was no statistically significant difference with the control group (p = 0.65).

CONCLUSION

The PRF patch seems to be a safe and efficient covering technique. Thus, procedure is an additional approach to coverage for hypospadias surgery, and may help to reduce the incidence of postoperative complications when coverage healthy tissue is not available.

[Gliomatosis peritonei, an unusual abdominal carcinomatosis: report of two cases]

We report on 2 cases of ovarian teratoma associated with gliomatosis peritonei in 2 young girls aged 9 and 14 years. Gliomatosis peritonei is an unusual miliary-like peritoneal carcinomatosis of glial tissue. In our experience, follow-up was important to detect abdominal recurrence of glial implants, which had to be removed by iterative surgery. We report a 14-year follow-up and an unusual pleural metastatic disease.

Congenital diaphragmatic hernia: prenatal diagnosis permits immediate intensive care with high survival rate in isolated cases. A population-based study

OBJECTIVES

To estimate the prognosis of prenatally diagnosed isolated congenital diaphragmatic hernia (PDICDH) treated with 'immediate planned care' (IPC) between 1999 and 2003 in Eastern Brittany.

METHODS

The prognosis of PDICDH was compared with the prognosis of the other live-born CDH, either prenatally undiagnosed or not having had IPC. IPC consisted in prenatal lung maturation with corticosteroids, elective caesarean section at 37 weeks, immediate intubation, surfactant, high- frequency ventilation or oscillation, nitric oxide, intravenous prostacyclin, anaesthesia and haemodynamic support. Surgical repair was performed in the NICU 34 h after birth.

RESULTS

The incidence of CDH was 0.8 per thousand with a prenatal diagnosis rate of 27/30 (90%), leading to a termination of pregnancy in nine cases. Ten CDH were associated with other malformations. IPC in PDICDH was performed in 12 cases. The survival rate of PDICDH with IPC was 11/12 versus 1/9 in CDH with no IPC or no prenatal diagnosis (p < 0.01). Logistic regression analysis showed that IPC was determinant for survival (p < 0.01).

CONCLUSION

Prenatal diagnosis of isolated CDH treated with immediate planned care is associated with a high survival rate. This suggests that prenatal diagnosis associated with specifically adapted postnatal procedure may improve the prognosis of isolated CDH.

Hypothermic storage and cryopreservation of hepatocytes: the protective effect of alginate gel against cell damages

Hepatocyte-based therapy has been proposed as an alternative to organ transplantation in the treatment of liver disorders. In the clinical context, a major issue is the constant supply of quality assurance-controlled hepatocytes, thereby requiring their cold storage in good conditions. We have analyzed the protective effects of alginate entrapment of rat hepatocytes after either 24 or 48 h of hypothermic storage or cryopreservation on the cell viability, cell yield, both mitochondrial and other cytoplasmic functional activities, and apoptosis. Decrease in viability, as evaluated by the MTT inclusion test, was 4% and 13% (24 h at 4 degrees C), 15% and 33% (48 h at 4 degrees C), and 9% and 19% (liquid nitrogen) for entrapped and free suspended hepatocytes, respectively. Viable cell yields were 86 +/- 8% and 51 +/- 6% for cryopreserved entrapped and free suspended hepatocytes, respectively. The mitochondrial (MTS assay), 7-ethoxyresorufin O-deethylase (EROD), and glutathione-S-transferase (GST) activities were better preserved in entrapped than in free suspended hepatocytes. Both hypothermic storage and cryopreservation were found to induce early caspase-3-like activities, being always much lower in entrapped hepatocytes, particularly after cryopreservation (98.4 +/- 42.4 vs. 6.4 +/- 4.0 fluorescence arbitrary units/hours/microg protein). Thus, cold-induced apoptosis in hepatocytes can be significantly reduced following their entrapment within alginate gel beads and this is associated with an improvement of both their viability and function.

Perinatal management and outcome of prenatally diagnosed congenital diaphragmatic hernia: a 1995-2000 series in Rennes University Hospital

OBJECTIVES

To assess the prognosis of prenatally diagnosed congenital diaphragmatic hernia (CDH) during the years 1995-2000 in order to improve prenatal counselling.

METHODS

Retrospective study of all 31 cases of women with prenatally diagnosed CDH.

RESULTS

Nine pregnancies (29%) were terminated and two fetuses (6%) were stillborn. Ten fetuses (32%) had associated anomalies (four Fryns' syndrome) and four (13%) had underlying chromosomal anomalies. Twenty pregnancies were continued. Seven babies died before surgery either immediately in the delivery room (five between 1 and 45 min), or during the 'stabilisation period' (two babies, 7 and 21 h). Three babies presented with trisomy 18, Fryns' syndrome or transposition of the great arteries with microdeletion 22q11. Thirteen babies had the defect repaired (median 18 h, range 4-72 h) and 12 survived. Mechanical ventilation was required for a median of 12 days. One survivor has cerebral palsy.

CONCLUSION

Of 31 prenatally diagnosed CDH cases 38% are alive, of 20 ongoing pregnancies 60% are alive, and of 13 babies who underwent surgery 92% are alive. No baby with associated malformations survived. These numbers need to be known by each member of the counselling team in order to give parents adequate information to make their decision.

Follow-up by one- and two-dimensional NMR of plasma from pigs with ischemia-induced acute liver failure treated with a bioartificial liver

Hepatic encephalopathy may occur following acute hepatic failure (AHF), which results in the release of toxic compounds from the injured liver. These compounds, which induce cerebral edema, are not well characterized, yet. The aim of this study was to evaluate the potential interest of NMR spectroscopy in the follow-up of different plasma compounds in pigs with ischemia-induced fulminant hepatic failure treated or not with a bioartificial liver (BAL), which has been previously shown to improve the neurological status of the animals. Qualitative analysis of pig plasma was achieved by one-dimensional-(1)H CPMG, two-dimensional homonuclear (1)H-(1)H TOCSY CPMG and heteronuclear (1)H-(13)C HSQC sequences. Semi-quantitative analysis of selected plasma metabolites along the disease evolution was carried out on pigs with ischemia-induced AHF treated with the BAL containing alginate beads with or without hepatocytes. A quantitative longitudinal follow-up was performed on characteristic metabolites via a one-dimensional CPMG sequence, including choline, glutamine, N-acetyl-glucosamine (NAG), pyruvate and trimethylamine-N-oxide (TMAO). The concentrations of choline and TMAO increased from the beginning to the end in animals treated with the BAL containing alginate beads without hepatocytes. Treatment of pigs with BAL containing hepatocytes resulted in an improvement of survival, the plasma concentrations of choline and TMAO being decreased in three out of five animals. Thus, NMR spectroscopy is a useful approach for the identification of toxic compounds which are involved in hepatic encephalopathy associated with AHF. These compounds can be cleared by a BAL resulting in the improvement of survival and neurological parameters of the animals.

Reduced encephalopathy in pigs with ischemia-induced acute hepatic failure treated with a bioartificial liver containing alginate-entrapped hepatocytes

OBJECTIVE

To analyze the effects of an extracorporeal bioartificial liver containing alginate bead-entrapped hepatocytes on pigs with ischemia-induced acute hepatic failure.

DESIGN

Prospective animal study.

SETTING

University and INSERM laboratory.

SUBJECTS

Fifteen Large White/Pietrin female pigs weighing 20-30 kg.

INTERVENTIONS

Acute hepatic failure was induced by end-to-side portocaval shunt and ligature of the whole porta hepatitis. The bioartificial liver was in a thermostabilized column, containing a fluidized bed of alginate beads that embedded porcine hepatocytes, connected to a plasmapheresis system. Intracranial pressure; survival; ammonia, total bilirubin, aminotransferases, alkaline phosphatase, and lactate concentrations; and clotting factors were studied. The groups were pigs with acute hepatic failure (group 1, n = 4), pigs with acute hepatic failure treated with bioartificial liver containing empty beads (group 2, n = 4), or porcine hepatocytes (group 3, n = 5).

MEASUREMENTS AND MAIN RESULTS

In group 1, survival of pigs averaged 10.9 +/- 1.0 hrs; intracranial pressure reached 32.3 +/- 3.8 mm Hg and was associated with coma and cerebral edema. After connection to the bioartificial liver, the survival of acute hepatic failure pigs was 12.1 +/- 1.4 hrs in group 2 and 14.8 +/- 2.5 hrs in group 3. In group 3, intracranial pressure and bilirubin concentrations were reduced significantly compared with both group 1 and group 2. Neither signs of encephalopathy nor cerebral edema was observed in any animal of group 3. In all animals, plasma ammonium, aminotransferases, alkaline phosphatase, and lactate concentrations increased and clotting factors decreased with no significant differences between the three groups. Autopsy revealed a total necrosis of the liver, which was histologically confirmed.

CONCLUSIONS

The ischemia-induced model of acute hepatic failure in pigs is reproducible and provides measurable clinical and biological features. A bioartificial liver containing alginate bead-entrapped hepatocytes improves the signs of encephalopathy in pigs with ischemia-induced acute hepatic failure, suggesting that the bioartificial liver can clear out toxic compounds that are released from necrotic livers.

Detoxifying activity in pig livers and hepatocytes intended for xenotherapy

BACKGROUND

Both livers and hepatocytes from pigs have been proposed for the treatment of end-stage liver diseases, as an alternative to allogeneic liver transplants. However, little is known of the capability of porcine hepatocytes to fulfill the biotransformation pathways of toxic compounds, including those released from livers in acute failure. We have studied the activity and expression of detoxifying enzymes in porcine livers and in cultured hepatocytes and their induction by phenobarbital.

METHODS

Cytochromes P450 (CYP) 1A, 2B, and 3A and GST-like activities were tested with the following specific substrates: 7-ethoxyresorufin, 7-pentoxyresorufin, nifedipine, testosterone, 1-chloro-2,4-dinitrobenzene, 1,2-dichloro-4-nitrobenzene, and ethacrinic acid. CYP 1A1/2-, 2B1/2-, 2E1- and 3A4-related and GSTalpha proteins were analyzed by Western blotting and CYP 1A1/2, 2B1/2, 2C6, 2E1, and 3A4, aldehyde dehydrogenase, epoxide hydrolase, and GSTalpha-like RNA by Northern blotting.

RESULTS

Enzymatic activities reflecting the expression of CYP 1A-, CYP 2B-, CYP 2E1-, and CYP 3A-like genes, that is, ethoxyresorufin-O-deethylase, pentoxyresorufin-O-deethylase, nifedipine oxidase and testosterone 6beta-hydroxylase, and chlorzoxazone 6-hydroxylase, were identified in pig livers. CYP 1A and CYP 2E1, GSTalpha-like proteins, CYP 1A, 2C, and 2E, epoxide hydrolase, aldehyde dehydrogenase, and GST like RNA were expressed in vivo and in vitro. CYP 2B and CYP 3A RNA and proteins, and their associated activities were induced by phenobarbital.

CONCLUSIONS

Porcine hepatocytes express the most important biotransformation enzymes and their corresponding activities and RNA. Thus, livers and hepatocytes from pigs can detoxify a large spectrum of exogenous and endogenous compounds, which makes them a convenient substitute for allogeneic transplants for patients with liver failure.

[Hepatocytes in cell therapy]

Cell-based therapy could represent an alternative treatment to orthotopic liver transplantation in acute liver failures and for the correction of genetic defects of various enzymatic functions. Several recent studies indicate that hepatocytes injected either in the spleen or in portal vein can restore liver-specific function(s) in animal model systems. Alternatively, an extracorporal hybrid bioartificial liver might provide liver-specific functions, maintain the patient alive and allow spontaneous recovery of the patient's own liver, or act as a bridge toward liver transplantation in acute liver failures. Various drawbacks of devices such as flat culture substrates, hollow-fiber bioreactors or microcarriers led us to develop a reliable extracorporeal bioartificial liver based on alginate-entrapped hepatocytes. This system was used successfully for the correction of the Gunn rat genetic defect which results in the lack of bilirubin conjugation. The development of this system for clinical purposes requires large yields of functional hepatocytes. We isolated porcine hepatocytes by collagenase perfusion of the liver and cells were immobilized within alginate beads which were subsequently inoculated in a bioreactor. Porcine hepatocytes expressed liver-functions at high levels, particularly those involved in detoxification and biotransformation processes; they were immunoisolated from immunoglobins and could be cryopreserved. This system represents a promising tool for the design of an extracorporeal bioartificial liver in human beings.

Intestinal vascular anomalies in children

Vascular anomalies are an uncommon cause of gastrointestinal bleeding in childhood. Confusing nomenclature has made objective comparisons of published cases difficult and has interfered with an established consensus regarding diagnosis and therapeutic modalities. The purpose of this study was to clarify the situation by reviewing the records of all children who had intestinal vascular anomalies who were referred to our institution from 1975 to 1995. Thirteen lesions were identified in nine children (five boys and four girls). The median age at clinical onset was 8 years. Only two patients presented with a complex syndrome (Klippel-Trenaunay, 1; Osler-Rendu-Weber, 1). Diagnosis, location, and extension of these anomalies was only possible by angiography, which indicated that seven patients had isolated venous malformations and two had arteriovenous malformations. Because the lesions did not involve the serosa, intraoperative localization was a major problem. The main findings were a few slightly dilated mesenteric veins. Treatment was conservative in four children and surgical in five. Pathological findings on resected bowel demonstrated dilated and abnormal veins in the mucosa and submucosa. Selective angiography should not be delayed in patients with gastrointestinal bleeding if results of all other investigations are negative. Because these lesions are rarely recognizable on operative inspection, precise preoperative angiographic localization of intestinal vascular anomalies is essential to allow for a safe and limited resection of the involved bowel segment. Based on a better understanding of the natural history of these lesions, a classification of vascular anomalies of intestines in children is proposed.

Mesenteric adenitis caused by Yersinia pseudotuberculosis presenting as an abdominal mass

Infection by Yersinia pseudotuberculosis has become of increasing pathological importance. Patients normally present with symptoms similar to those of appendicitis, due to mesenteric adenitis. We present the case of 3 patients infected by Yersinia pseudotuberculosis who in addition to fever and abdominal pain had a palpable abdominal mass, so great was the enlargement of the mesenteric nodes. In 2 patients a laparotomy was carried out, followed by biopsy of a mesenteric lymph node. The diagnosis of Yersinia infection was confirmed by bacterial culture of the biopsied material and also by serology. In the third patient, serological studies and ultrasonic imaging of the abdomen led to early diagnosis and surgery was avoided. We suggest that a diagnosis of mesenteric adenitis due to Yersinia pseudotuberculosis should now be considered in all patients presenting with an abdominal mass, and in whom there is an appropriate clinical and epidemiological history. The diagnosis should be confirmed by abdominal ultrasound (alternatively Computerised Axial Tomography or Magnetic Resonance Imaging) and serological studies. In this way, unnecessary surgery can be avoided.

Cell-based therapy of acute liver failure: the extracorporeal bioartificial liver

The need for an alternative treatment to orthotopic liver transplantation for acute liver failure is a major issue, and systems capable of temporarily providing liver functions are being actively tested. Liver assist devices based on detoxication by dialysis or hemoperfusion through various membranes or cartridges proved to be inefficient because of their lack of metabolic function. An extracorporeal hybrid bioartificial liver might be an appropriate treatment, since it can provide liver-specific functions, maintain the patient alive, and allow spontaneous recovery of the patient's own liver or act as a bridge toward liver transplantation. Many devices have been proposed, including flat culture substrates, hollow-fiber bioreactors, or microcarriers, using xenogenic hepatocytes or hepatoma cell lines. Various drawbacks of these devices led us to attempt to develop a reliable extracorporeal bioartificial liver based on alginate bead-entrapped hepatocytes. This system was used successfully for the correction of the Gunn rat genetic defect, which results in lack of bilirubin conjugation. The development of this system for clinical purposes requires large yields of functional hepatocytes. We have isolated normal porcine hepatocytes by collagenase perfusion of the liver. Cells were immobilized in membrane-coated alginate gel beads, which were subsequently inoculated into a bioreactor. Porcine hepatocytes expressed liver-specific functions at high levels, particularly protein neosynthesis and enzymatic activities involved in detoxication and biotransformation processes. In addition, hepatocytes entrapped in coated alginate beads were isolated from immunoglobulins. This system represents a promising tool for the design of an extracorporeal bioartificial liver in human beings.

[A step towards a bioartificial liver: temporary extracorporeal replacement using isolated hepatocytes]

The mortality rate of fulminant hepatic failure is about 80%. Besides orthotopic liver transplantation, specific therapies are not currently available. Indeed, not only removal of toxins is required, by means of dialysis or hemoperfusion, but specific hepatic functions must be provided to allow spontaneous liver regeneration or as a bridge before liver transplantation. Treatment with an extracorporeal bioartificial liver is an attractive approach. This system was successfully used for the correction of the Gunn rat genetic defect which results in the lack of bilirubin conjugation. The development of this system for clinical purpose requires both a large yield of functional hepatocytes and their immunoprotection in an appropriate device. We have isolated normal porcine hepatocytes by collagenase perfusion of the liver; cells are subsequently entrapped within membrane-coated alginate beads which are inoculated in a bioreactor. Plasma from an animal undergoing fulminant hepatic failure by end-to-site portocaval shunt and whole porta hepatic tightening circulates within the bioreactor. Porcine hepatocytes express liver-specific functions at high levels, particularly secretion of plasma proteins and several enzyme activities involved in the detoxication and biotransformation of xenobiotics. In addition, hepatocytes are immunoseparated from circulating immunoglobulins. Ethical concerns are discussed in the field of physiopathology, immunopathology and public health, as a prerequisite to create departments of Cell Therapy, in the near future.

Late presenting Bochdalek hernia containing colon: misdiagnosis risk

The case of an eleven-months-old girl is reported: she entered the intensive care unit for fever, vomiting and left pleural effusion. Abdominal echography, CT scan and colonic opacification led to the diagnosis of a colonic Bochdalek hernia. A review of the literature showed that colonic hernias are rare, with only five previous reported cases in which colon was found in the thorax. The authors emphasise that there is a high risk of misdiagnosis due to the fact that small intestine contrast studies are normal; only colonic contrasting may lead to the right diagnosis. The roles of echography and CT scan are discussed.

Viability and function in primary culture of adult hepatocytes from various animal species and human beings after cryopreservation

Cryopreserved hepatocytes from various animal species and human beings were tested for their ability to survive and function in primary culture. The freeze/thaw protocol primarily designed for rat hepatocytes was used with slight modifications for the cells of all other species; it consisted of suspending parenchymal cells in the Leibovitz L15 medium containing 10% fetal calf serum and 10% to 16% dimethyl sulfoxide. After transient storage at 4 degrees C cell suspensions were transferred to -20 degrees C and then to -70 degrees C before being plunged in liquid nitrogen. Hepatocytes were stored for a few weeks to 4 yr. Prolonged storage did not augment loss of cell viability and function. Cell viability after thawing was estimated by the trypan blue exclusion test, and attachment efficiency to plastic was estimated by measuring intracellular lactate dehydrogenase content. Similar values were obtained for most species tested; after cryopreservation cell viability and attachment were decreased by 10% to 25% and by 40% to 50%, respectively. A lower attachment rate was found with dog hepatocytes. Total cytochrome P-450 and protein synthesis were compared in fresh and cryopreserved cells from four species after 4, 24, 48 or 72 hr of culture. Similar values were found in both cells after 24 or 48 hr of culture. In addition, drug-metabolizing activities were measured in human hepatocytes from five donors. In most cases phenacetin deethylation activity was decreased whereas procainamide N-acetylation and paracetamol sulfoconjugation and glucuronidation were increased in cryopreserved cells.(ABSTRACT TRUNCATED AT 250 WORDS)

[Anterior rectal duplication. Value of ultrasonic diagnosis]

A case of neonatal anterior rectal duplication is reported. Abdominal ultrasonography revealed a prerectal cystic mass. The different types of rectal duplications and the main differential diagnosis are described. Mechanical obstruction and neoplastic risk make early surgery necessary.

Primary megaureter in the neonate with prenatal or postnatal diagnosis

Twenty-nine cases of primary megaureter diagnosed before the age of 3 months are grouped in this diagnostic and therapeutic study. Seventy-five per cent were discovered by antenatal sonography due to the presence of pelvicalyceal dilatation without localising precisely the position of obstruction, twenty-five per cent were detected by the occurrence of early urinary tract infection. Four patients were operated during the first few months. 2 diversions and 2 reimplantations. Fifteen including the 2 with early diversion were submitted to later reimplantation at the average age of 15 months. 12 patients were treated conservatively by antibiotics and regular supervision. The respective results of the operated and non-operated patients were evaluated comparing the initial dilatation and the last IVU using the classification of Beurton. Regardless of the marked initial dilatation, significant spontaneous regression or complete resolution were often seen during the first year of follow-up. Thus surgery should be deferred initially even for the severely dilated forms, except in a few critical cases where a diversion is indicated. Reimplantation should be deferred for some months unless deterioration is noted, or performed only after one year or 18 months if regression is insufficient, thus optimising operative conditions.