[Tetralogy of Fallot in monozygotic twins]

The causative mechanisms of congenital heart defects remain unclear and little is known about the respective implication of chance, genetics and environment, though recent findings in molecular biology may provide further insight into understanding the pathophysiologic basis of congenital heart diseases.

CASE REPORT

We report the exceptional but significant case of monozygotic twins both affected by tetralogy of Fallot, for whom prenatal diagnosis ruled out 22q11 microdeletion.

CONCLUSION

We discuss how far this observation is consistent with the latest hypothesis, which emphasizes the leading role of genetic factors. Several genes indeed, either separately or in combination, could be responsible for those defects, even if other influences may still come into play.

Physicians' attitudes towards health telematics--an empirical survey

Telemedical networks and services have received high attention in professional and scientific media in the recent past. In Germany some institutions and few physicians volunteer in experimenting with diverse telemedical service offerings. However, much is speculated but little is known about attitudes and expectations of the majority of physicians in local offices towards this new medium. Therefore we conducted an empirical survey using a random regional sample to poll the respective opinions. Encouraged by a high response rate to our paper questionnaire, we offer as conclusion: that physicians are surprisingly realistic about costs and benefits and can therefore be expected to subscribe as soon as benefits become obvious; that this trend increases with offices being taken over or newly established by younger physicians; and that the establishment of networks of comprehensive care offered by health care professionals from different disciplines is regarded as essential future advantage of telemedical networks.

Recurrence of hydatid disease

Surgical management of hepatic hydatid disease has been associated with an overall local recurrence rate of approximately 10%. Local recurrence is rarely seen following complete resection of an intact cyst and is usually the result of spillage of live parasites or leaving a residual cyst wall containing germinal epithelium, daughter cysts, or protoscolices during surgery. Recurrence is frequently asymptomatic, so the diagnosis depends on dedicated follow-up of treated patients with serology and either ultrasonography or computed tomography. The management of locally recurrent disease should include administration of albendazole followed by the appropriate application of interventional radiotherapy or operation. As with the treatment of primary disease, the preservation of liver function and minimizing the risk to the patient remain the guiding principles of therapy of local recurrence.

Antiphospholipid antibodies and preeclampsia: a case-control study

OBJECTIVE

To assess the association between the occurrence first of preeclampsia and antiphospholipid antibodies.

METHODS

We conducted a prospective case-control study of 180 pregnant women with their first incidents of preeclampsia and no histories of thrombosis or systemic autoimmune diseases. Preeclampsia (n = 180) was defined as blood pressure (BP) at least 140/90 mmHg after 20 weeks' gestation and proteinuria at least 0.3 g per 24 hours. Two control subjects were matched to each case (n = 360). They were pregnant women without hypertension or proteinuria and without histories of thrombosis or systemic autoimmune disease. Lupus anticoagulant (activated partial thromboplastin time, diluted thromboplastin time, platelet neutralization procedure) and anticardiolipin antibodies (immunoenzymatic assays) were assessed in both groups, and the coagulation state (levels of thrombin-antithrombin III complexes, fragments 1 + 2 of prothrombin) was also evaluated. The analysis design was a sequential plan with 5% type I error and 95% power.

RESULTS

There was no association between antiphospholipid antibodies and preeclampsia. The odds ratio for the association was 0.95 (95% confidence interval 0.45, 2.61). Antiphospholipid antibodies were detected in eight of 180 preeclamptic women and in 19 of 360 controls. In contrast, there was a clear, confirmed activation of coagulation during preeclampsia.

CONCLUSION

Despite evidence of a prothrombotic state during preeclampsia, it is unlikely that antiphospholipid antibodies (lupus anticoagulant and anticardiolipin antibodies) represent risk factors for preeclampsia among women with no previous preeclampsia and no histories of thrombosis or systemic autoimmune disease.

Sudden interchannel interaction in the Tl 6p ionization above the 5d threshold

The linear magnetic dichroism in the angular distribution of Tl 5d and 6p photoelectrons and their dynamical spin polarization have been measured between hnu = 30 and 50 eV. In contrast to the Xe 5p photoionization at the 4d threshold, our results show that above the Tl 5d threshold strong interchannel coupling effects induce a sudden increase in the asymptotic phase difference of the s and d waves for the Tl 6p ionization. This shows that the valence excitation is different for resonant (Xe 4d) and nonresonant (Tl 5d) excitation from subvalence shells.

Prenatal sonographic diagnosis of skeletal dysplasias. A report of 47 cases

The purpose of this study was to evaluate the foetal sonographic efficiency for prenatal diagnosis of osteochondrodysplasias. Forty-seven prenatal and postnatal cases diagnosed between January 1993 and December 1998 in the referral sonographic centres of Strasbourg were studied. All cases were reviewed retrospectively and the prenatal ultrasound findings and diagnosis were compared to the postnatal or post-mortem diagnosis. Each case was studied by ultrasonographers, geneticists, radiologists, and foetopathologists. Final diagnosis was based on clinical examination, skeletal survey and molecular testing as deemed necessary. Routine screening and dating was the indication for foetal sonography in 72% (32/47) of our cases. The most likely time of diagnosis was between 16 and 24 weeks of gestation (17 out of 47 cases, 36%), which corresponds to the time of foetal anomaly sonographic scan in France. The other cluster of cases (12 among 47, 26%) was disclosed before 16 weeks of gestation. These results illustrate the importance of a detailed evaluation of the limbs during sonographic examinations of first and second trimesters of pregnancy. While the identification of skeletal dysplasias was relatively easy in our study, the ability to make an accurate specific antenatal diagnosis was more difficult. An accurate diagnosis was proposed in 28 of the 47 cases (60%). In 19% of the cases (9/47), the prenatal diagnosis was not accurate; in 21% of the cases (10/47), the prenatal diagnosis was imprecise. In 45 of the 47 cases (96%) prenatal foetal scan correctly predicted the prognosis.

Biliary stenting versus bypass surgery for the palliation of malignant distal bile duct obstruction: a meta-analysis

The objective of this analysis is to compare endoscopic stenting with surgical bypass in patients with unresectable, malignant, distal common bile duct obstruction using the technique of meta-analysis. The inclusion criteria for the studies were randomized patient assignment, publication in the English language, 20 or more patients per group, all patients followed up until death, and follow-up and complications reported in an equivalent way for both treatment arms. Data extraction was performed independently by 2 of the authors. The number of treatment failures, serious complications, requirement for additional treatment sessions, and 30-day mortality were extracted. Three existing trials met the inclusion criteria, all of which compared surgery with the use of plastic stents. There were no studies identified that used metallic expandable stents. For the rate of treatment failure and serious complications, the odds ratios (ORs) of the 3 trials were heterogeneous, and no summary ORs were calculated. More treatment sessions were required after stent placement than after surgery, and a common OR was estimated to be 7.23 (95% confidence interval [CI], 3.73 to 13.98). Thirty-day mortality was not significantly different (OR = 0.522; 95% CI, 0.263 to 1.036). Although surgical bypass required fewer additional treatment sessions, existing data do not allow a definitive conclusion on which treatment is preferable. A larger randomized controlled trial using newer metallic stents and proper quality-of-life instruments is required.

Distinct internalization of M2 muscarinic acetylcholine receptors confers selective and long-lasting desensitization of signaling to phospholipase C

Although M1-M4 muscarinic acetylcholine receptors (mAChRs) in HEK-293 cells internalize on agonist stimulation, only M1, M3, and M4 but not M2 mAChRs recycle to the plasma membrane. To investigate the functional consequences of this phenomenon, we compared desensitization and resensitization of M2 versus M4 mAChRs. Treatment with 1 mM carbachol for 1 h at 37 degrees C reduced numbers of cell surface M2 and M4 mAChRs by 40-50% and M2 and M4 mAChR-mediated inhibition of adenylyl cyclase, intracellular Ca2+ concentration ([Ca2+]i) increases, and phospholipase C (PLC) activation by 60-70%. Receptor-mediated inhibition of adenylyl cyclase and [Ca2+]i increases significantly resensitized within 3 h. However, M4 but not M2 mAChR-mediated PLC activation resensitized. At 16 degrees C, M2 mAChR-mediated [Ca2+]i increases and PLC stimulation desensitized to a similar extent as at 37 degrees C. However, at 16 degrees C, where M2 mAChR internalization is negligible, both M2 mAChR responses resensitized, demonstrating that M2 mAChR resensitization proceeds at the plasma membrane. Examination of M2 mAChR responses following inactivation of cell surface mAChRs by quinuclidinyl benzilate revealed substantial receptor reserve for coupling to [Ca2+]i increases but not to PLC. We conclude that M2 mAChR internalization induces long-lasting PLC desensitization predominantly because receptor loss is not compensated for by receptor recycling or receptor reserve.

Congenital cholesteatoma and cholesterol granuloma of the temporal bone: role of magnetic resonance imaging

Magnetic resonance imaging (MRI) can be of significant benefit in characterizing expansile lesions of the petrous apex. MRI can be of particular help in distinguishing congenital cholesteatoma from cholesterol granuloma. Furthermore, with the advent of faster high-resolution scanning techniques, MRI can define precise spatial relationships of these masses with the middle and inner ear structures, internal carotid artery, jugular vein, and other structures of the skull base. MRI scanning is sensitive in detecting intracranial extension of these masses. MR angiography can provide additional information regarding the relationship of these masses with adjacent vascular structures and confirm patency of the adjacent vessels. In the postoperative period, MR scanning can help evaluate for complete removal, complication, recurrence, or formation of complicating granulation tissue.

Two cases of Townes-Brocks syndrome

Townes-Brocks syndrome (TBS) has been recognized as a dominant inherited syndrome. We report 2 cases of TBS. Case 1 was operated on for imperforate anus. Triphalangeal thumb and ear anomalies were remarkable. Deafness was diagnosed when the patient was 6 months old. Anomalies of the semicircular canals and the incus with inculomalleolar fusion were shown when the patient was 3.5 years old. During childhood, recurrent episodes of abdominal pain appeared. The diagnosis of hereditary angioneurotic edema (HANE) was made. HANE was familial as the father, the father's brother and the paternal grand mother were also affected. The parents of case 2, a female, are both mildly mentally retarded. This was the first pregnancy of the mother who had short stature. The child had an antepositioned anus, bifid right thumb, large toes, low set ears, microretrognathia and deafness. A (5, 16) translocation was observed in a child with TBS. At the breakpoint in 16q21.1, a gene coding for a transcription factor SALL1 has been identified and it was shown that mutations in the putative zinc finger of SALL1 cause TBS.

[Bone marrow cellularity in acute lymphoblastic leukemia of children]

The early response to therapy in childhood acute lymphoblastic leukemia (ALL) is typically assessed by bone marrow status. The clearance of blast cells in peripheral blood and bone marrow during induction therapy was analysed in 38 children (27 precursor-B-ALL and 11 precursor T-ALL) treated according to BFM90 or New York 93 protocols. Leukocyte count and peripheral blood smear taken at diagnosis, day 8, day 14 and day 33 as well as bone marrow cellularity and percentage of blasts on days: 0, 14, 33 were analysed. The number of blasts in bone marrow was correlated to bone marrow cellularity (Spearman's rho = 0.72, p = 0.001). Patients with T-ALL were more frequently resistant to steroids in vivo and reached remission later in comparison to precursor-B-ALL children (p = 0.019), however blasts reduction ratio was comparable in both lineages. Bone marrow cellularity on days 14 and 33 of induction therapy was similar.

Hepatic resection of noncolorectal nonneuroendocrine metastases

Because hepatic resection is generally a safe procedure, the indications for resection of noncolorectal nonneuroendocrine (NCNNE) hepatic metastases have broadened. The prognostic features of NCNNE metastases treated surgically were reviewed to define better the value of resection. A retrospective review of patients undergoing liver resection for NCNNE metastases between 1978 and 1998 was undertaken. Thirty-seven patients were identified. Mean age was 56 years, with a median follow-up of 22 months. Primary tumor sites were grouped into gastrointestinal (GI) adenocarcinoma (small bowel, n = 4; pancreas, n = 2; esophagus, n = 1) and other (renal cell, n = 7; sarcoma, n = 7; melanoma, n = 5; adrenal, n = 3; unknown adenocarcinoma, n = 3; thyroid, n = 2; testicular, n = 1; ovarian, n = 1; breast, n = 1). All patients underwent surgery for cure. Metastases were synchronous in 14 patients. There was no surgical mortality. Overall 5-year survival rate was 45%. Five-year survival rates were better for patients with non-GI-origin metastases (60% v 0%; P =.01). Long-term survival was seen only in patients with non-GI-origin metastases. The extent of resection, presence of synchronous metastases, or disease-free interval from time of original disease to presentation with liver metastases were not predictive of outcome. We conclude that patients with NCNNE hepatic metastases can undergo liver resection with an expectation of prolonged survival. However, patients with liver metastases from GI primary tumors other than the colorectum are unlikely to show extended survival.

Hepatic resection of noncolorectal nonneuroendocrine metastases

Because hepatic resection is generally a safe procedure, the indications for resection of noncolorectal nonneuroendocrine (NCNNE) hepatic metastases have broadened. The prognostic features of NCNNE metastases treated surgically were reviewed to define better the value of resection. A retrospective review of patients undergoing liver resection for NCNNE metastases between 1978 and 1998 was undertaken. Thirty-seven patients were identified. Mean age was 56 years, with a median follow-up of 22 months. Primary tumor sites were grouped into gastrointestinal (GI) adenocarcinoma (small bowel, n = 4; pancreas, n = 2; esophagus, n = 1) and other (renal cell, n = 7; sarcoma, n = 7; melanoma, n = 5; adrenal, n = 3; unknown adenocarcinoma, n = 3; thyroid, n = 2; testicular, n = 1; ovarian, n = 1; breast, n = 1). All patients underwent surgery for cure. Metastases were synchronous in 14 patients. There was no surgical mortality. Overall 5-year survival rate was 45%. Five-year survival rates were better for patients with non-GI-origin metastases (60% v 0%; P =.01). Long-term survival was seen only in patients with non-GI-origin metastases. The extent of resection, presence of synchronous metastases, or disease-free interval from time of original disease to presentation with liver metastases were not predictive of outcome. We conclude that patients with NCNNE hepatic metastases can undergo liver resection with an expectation of prolonged survival. However, patients with liver metastases from GI primary tumors other than the colorectum are unlikely to show extended survival.

Prevalence and clinical outcome of hepatitis C infection in children who underwent cardiac surgery before the implementation of blood-donor screening

BACKGROUND AND METHODS

There are few data on the prevalence and clinical outcome of hepatitis C infection in children. We studied 458 children who underwent cardiac surgery in Munich, Germany, before 1991, when blood-donor screening for hepatitis C was introduced in Germany. Their mean age at first operation was 2.8 years; none of the children had received blood transfusions before or 'after cardiac surgery, and none of their mothers had antibodies to the hepatitis C virus (anti-HCV). We compared these patients with 458 control subjects matched for age and sex.

RESULTS

Sixty-seven (14.6 percent) of the 458 patients who had undergone cardiac surgery had anti-HCV, as compared with 3 (0.7 percent) of the control subjects (P<0.001). At a mean interval of 19.8 years after the first operation, 37 (55 percent) of the 67 patients who were positive for anti-HCV had detectable HCV RNA in their blood. The infection had cleared in the other 30 patients, as evidenced by negative results on three polymerase-chain-reaction analyses performed at six-month intervals. Only 1 of the 37 patients who were positive for HCV RNA had elevated levels of liver enzymes; that patient had severe right-sided congestive heart failure. Of the 17 patients who underwent liver biopsies, only 3 had histologic signs of progressive liver damage. These three patients had additional risk factors: two had congestive heart failure, and the third had also been infected with hepatitis B virus.

CONCLUSIONS

Children who had undergone cardiac surgery in Germany before the implementation of blood-donor screening for hepatitis C had a substantial risk of acquiring the infection. However, after about 20 years, the virus had spontaneously cleared in many patients. The clinical course in those still infected seems more benign than would be expected in people infected as adults.

Role of US in the detection, characterization, and staging of cholangiocarcinoma

Cholangiocarcinoma is a rare tumor with a broad range of pathologic and clinical manifestations that demonstrates a myriad of imaging findings. Recent experience indicates that a more definitive role is possible for ultrasonography (US) in the evaluation of cholangiocarcinoma. Dilatation of the intrahepatic bile ducts is the most frequently seen US abnormality in patients with ductal cholangiocarcinoma. Klatskin tumors classically manifest as segmental dilatation and nonunion of the right and left ducts at the porta hepatis. Papillary and nodular ductal cholangiocarcinoma are relatively easy to see at US: Papillary tumors resemble polypoid intraluminal masses, whereas nodular cholangiocarcinoma manifests as a discrete smooth mass with associated mural thickening. Infiltrating ductal cholangiocarcinoma at the porta hepatis is the most common subtype but is the most difficult to appreciate at US. Peripheral cholangiocarcinoma may be either nodular or infiltrating at US: The nodular form predominates and appears as a solitary mass with a distinct right lobe predilection, whereas the infiltrative form is rare and manifests as a diffusely abnormal liver echotexture. In capable hands, modern high-resolution US equipment with color Doppler imaging capability is highly sensitive in the detection, characterization, and determination of the potential for resectability of cholangiocarcinoma. Thus, use of US may obviate more invasive procedures in some patients and help identify those patients for whom further investigation would be contributory.

[Massive feto-maternal transfusion. Report of 3 cases with review of the literature]

Massive feto maternal hemorrhage is rare. Early diagnosis is important because massive feto-maternal hemorrhage has a poor prognosis. The clinical manifestations of transplacental hemorrhage are related not only to the size of the hemorrhage but also to the time at which the hemorrhage occurs. In women who are candidates for Rh immune prophylaxis, massive feto maternal hemorrhage may be detected by Kleihauer test and we suggest that 10 micrograms dose of immune globin should be administered for each estimated ml of Rh positive blood given, to prevent an immunization Disappearance of fetal cells by Kleihauer test or appearance residual antibody suggests the adequacy of therapy. Three cases of massive fetomaternal hemorrhage (more than 225 ml) are presented here. Two mothers was Rh negative and they are delivered of rhésus positive children, which necessitated the administration of large volume of anti D. One of the cases shows the possibility of association between choriocarcinoma and positive kleihauer test.

Routine prenatal care in Europe: the comparative experience of nine departments of gynaecology and obstetrics in eight different countries

OBJECTIVE

The aim of this study was to compare routine prenatal care in nine European obstetrics and gynaecology departments.

STUDY DESIGN

A survey was performed between October 1992 and November 1993 by means of a questionnaire. The questionnaire comprised 118 questions covering clinical examinations and investigations systematically performed during the pregnancy.

RESULTS

The survey revealed a certain number of differences between the types of prenatal care performed by each department. Thus, one notices differences to do the serological testing (toxoplasmosis, AIDS and hepatitis B) at the first visit and in the practice of vaginal examination, systematic ultrasound examination or cardiotocography.

CONCLUSION

The differences observed in the prenatal care furnished are only a reflection of our uncertainties concerning the validity of the various tests used to monitor pregnancies. At a time when financial restrictions impose choices, we consider an evaluation of the efficacy and cost of prenatal care to be essential.

[Prenatal and neonatal management of digestive tract duplications. Diagnostic difficulties and therapeutic implications]

OBJECTIVE

To insist on the difficulty of the antenatal diagnosis of digestive duplications, to show the importance of a complete malformative screening, and the need for immediate management at birth.

MATERIAL AND METHODS

A cystic duplication of the tongue, a duplication, abdomino-thoracic transdiaphragmatic, and a duplication of the small bowel are described and compared with cases previously reported in th literature.

RESULTS

Antenatal evacuation puncture of a duplication of the tongue must be reserved for exceptional situations. Foregut duplications are often associated with other malformations. The duplication of the small intestine can exceptionally expose to a mechanical complication, mostly during the postnatal period, which may require emergency surgery.

CONCLUSION

Duplications of the alimentary tract should be detectable on prenatal ultrasound examination. A complete antenatal malformative screening is required and in utero transfer is warranted because emergency surgery may be required.

[Clinical importance of fetal pulse oximetry. II. Comparative predictive values of oximetry and scalp pH. Multicenter study]

OBJECTIVE

To compare the predictive value of intrapartum fetal pulse oximetry to that of fetal blood analysis for an abnormal neonatal outcome in case of abnormal fetal heart rate (FHR).

STUDY DESIGN

A prospective multicenter observational study, from June 1994 to November 1995. Fetal oxygen saturation was continuously recorded using a Nellcor N-400 fetal pulse oximeter in case of abnormal FHR during labor. Simultaneous readings of fetal oxygen saturation and fetal blood analysis obtained before birth, i.e. either at full dilatation, or before cesarean section when indicated, were compared with the neonatal status. The criteria for an abnormal neonatal outcome were 1) an umbilical arterial blood pH < or = 7.15 and 2) a combined variable including: 5 min. Apgar score < or = 7, umbilical arterial pH < or = 7.15, secondary respiratory distress, transfer in a neonatal care unit, or neonatal death.

RESULTS

At a 7.20 threshold for fetal scalp pH, and 30% for fetal oxygen saturation (i.e. the tenth centile in the study population), the predictive value of fetal pulse oximetry was similar to that of fetal blood analysis for an arterial umbilical pH < or = 7.15, and for an abnormal neonatal outcome (positive predictive value 56% vs 55%, negative predictive value 81% vs 82%, sensitivity 29% vs 35%, and specificity 93% vs 91% respectively). The receiver operating curve showed similar performance of either technique for cut-off values < or = 7.20 for fetal blood pH and < or = 30% for fetal oxygen saturation, whereas fetal pulse oximetry became superior at higher thresholds.

CONCLUSION

The predictive value of intrapartum fetal pulse oximetry can be favorably compared with that of fetal blood analysis. Randomized controlled management trials can now be performed to assess potential clinical benefits of this new tool.

Temperature calibration under ultrafast MAS conditions

For conventional fast magic-angle spinning (MAS) frequencies (</=15 kHz), there is a known heating of the sample due to the friction between the rotor and the bearing gas. At the recently achievable ultrafast MAS frequencies of up to 35 kHz, a more dramatic heating effect is expected. Using the 119Sn NMR signal of the chemical shift thermometer Sm2Sn2O7, this frictional heating effect is quantified, and a calibration of the sample temperature under ultrafast MAS conditions is described. An empirical expression is given which allows the determination of the sample temperature as a function of the bearing gas temperature and the spinning frequency. Copyright 1999 Academic Press.

Relation between hospital surgical volume and outcome for pancreatic resection for neoplasm in a publicly funded health care system

BACKGROUND

Recent studies from the United States have shown that institutions with higher numbers of pancreatic resection procedures for neoplasm have lower mortality rates associated with this procedure. However, minimal work has been done to assess whether the results of similar volume-outcome studies within a publicly financed health care system would differ from those obtained in a mixed public-private health care system.

METHODS

A population-based retrospective analysis was used to examine pancreatic resection for neoplasm in Ontario for the period 1988/89 to 1994/95. Outcomes examined included in-hospital case fatality rate and mean length of stay in hospital. For each hospital, total procedure volume for the study period was defined as low (fewer than 22), medium (22-42) or high (more than 42). Regression models were used to measure volume-outcome relations.

RESULTS

The likelihood of postoperative death was higher in low-volume and medium-volume centres than in high-volume centres (odds ratio 5.1 and 4.5 respectively; p < 0.01 for both). Mean length of stay was greater in low- and medium-volume centres than in high-volume centres (by 7.7 and 9.2 days respectively, p < 0.01 for both).

INTERPRETATION

This study adds to growing evidence that, for pancreatic resection for neoplasm, patients may have better outcomes if they are treated in high-volume hospitals rather than low-volume hospitals.

[Clinical importance of fetal pulse oximetry. I. Methodological evaluation. Multicenter study. French Study Group on Oximetry of Fetal Pulse]

OBJECTIVE

To evaluate the feasibility of intrapartum fetal pulse oximetry, the distribution of fetal oxygen saturation values, and the relation with the neonatal outcome in a population with an abnormal fetal heart rate (FHR).

STUDY DESIGN

A prospective multicenter observational study, from June 1994 to November 1995. Fetal oxygen saturation was continuously recorded using a Nellcor N-400 fetal pulse oximeter in case of abnormal FHR during labor. Simultaneous readings of fetal oxygen saturation and of fetal blood analysis (FBA) were obtained at inclusion and before birth. Feasibility, adverse effects, distribution of fetal oxygen saturation values and relation with neonatal outcome were assessed.

RESULTS

74 patients were included. From 172 attempted sensor placements, the procedure was impossible in three cases and fetal oxygen saturation values were obtained in 164 cases (95.3%). Physicians considered sensor placement an easier task than FBA attempt (easy in 87.5% vs 78.9% for FBA, p = 0.03). The mean reliable signal time (+/- SD) was 64.7 +/- 32% during the first stage. There were no serious adverse effects in the study population. The mean fetal oxygen saturation during the first stage of labor was 42.2 +/- 8.0% (10th-90th centile range: 30-53%). Fetal oxygen saturation was significantly correlated with scalp pH (r = 0.29; p = 0.01) but not with neonatal umbilical artery pH or gas values. There was a significant association between a low fetal oxygen saturation (< 30%) and a poor neonatal condition.

CONCLUSION

The feasibility of fetal pulse oximetry is satisfactory in clinical practice. It is easy to use and provides a fair rate of recorded values, even in a population with suspicion of fetal distress. A low fetal oxygen saturation is significantly associated with an abnormal neonatal outcome.

Helium Double Photoi

The present status of double photoionisation studies is comprehensively reviewed. Recent findings are described which shed some light on the transition from the correlated motion of the two electrons near threshold to the shakeoff-like behaviour at higher photon energies. For extremely high photon energies, where Compton scattering becomes the dominant process, new results for the He2+ /He+ ratio between 6 and 120 keV are presented. The results confirm the prediction of Bergstrom et al. that the ratio reaches an intermediate maximum between 12 and 15 keV, before declining towards the asymptotic limit. Furthermore, this asymptotic limit seems not to be reached even at energies as high as 120 keV.

The behavior of substrate analogues and secondary deuterium isotope effects in the phenylalanine ammonia-lyase reaction

Metacresol and glycine can be thought as a dissection of metatyrosine, which is an excellent substrate of phenylalanine ammonia-lyase (PAL) (B. Schuster and J. Rétey, PNAS 92, 8433, 1995). Whereas metacresol was a very weak inhibitor and glycine was inert, simultaneous addition of both compounds led to synergistic inhibition of PAL. [2H5]Phenylalanine as a substrate showed a kinetic deuterium isotope effect of 9% (kH/k2H = 1.09 +/- 0.01) while its Km value was identical to that of the unlabeled substrate. The following substrate analogues were synthesized and assayed with PAL: cyclooctatetraenyl (COT)-d,l)-alanine as well as 2-pyridyl-, 3-pyridyl-, and 4-pyridyl-(l)-alanines. While COT-(d,l)-alanine turned out to be a rather reluctant substrate, all three isomers of pyridyl-(l)-alanines were converted with a comparable or even higher Vmax than l-phenylalanine into the corresponding pyridyl acrylic acids. Their Km values were, however, an order of magnitude higher than that of the natural substrate. These results are discussed in terms of the novel mechanism which implies an electrophilic attack of the prosthetic dehydroalanine at the aromatic ring. The heats of formation of the putative sigma complexes of the electrophilic substitution at the pyridine ring have been calculated using semiempirical force-field methods. The results show the feasibility of the proposed mechanism also with the substrate analogues.

[Management of Rhesus isoimmunization. Viewpoint of the obstetrician]

Although rare, severe forms of Rhesus isoimmunization are still observed. Early diagnosis and treatment with intrauterine transfusions allow an 80% survival rate. Anti-D alloimmunizations usually result from missed prophylaxis with anti-D serum at delivery, thus underlying the need for a rigorous application of this prophylaxis.

Low-field dedicated magnetic resonance imaging: a potential tool for assisting perinatal autopsy

Although the practice of perinatal autopsy has increased in recent years, examination of the fetus and especially of the fetal brain during the first trimester or the beginning of the second trimester remains difficult. Postmortem high-resolution images of the brain of a normal and an abnormal fetus of the same gestational age (22 weeks) were obtained with a low-field (0.1 T) dedicated magnetic resonance imaging (MRI) system. We demonstrated that a small MRI machine supplemented data from classical necropsy and may help in the interpretation of in utero ultrasound and magnetic resonance images for the antenatal diagnosis of fetal malformations.

Etiology and prevention of pulmonary complications following beta-mimetic mediated tocolysis

OBJECTIVES

This study documents biological (haematocrit variations) and therapeutic parameters (salbutamol doses, volumes perfused) in two groups tocolysed with salbutamol, one with and the other without APO in order to define the risk factors linked to APO and to establish a standard protocol of management.

STUDY DESIGN

This retrospective study includes data from 68 intravenous salbutamol tocolysis with four resulting APOs, carried out between January 1st, 1993 and December 31st, 1995.

RESULTS

There was an excessive level of salbutamol administered over 48 h in the complicated APO-group (122.5+/-52 mg) opposed to the non-APO group (44.9 21 mg) as well as an overload of perfused solute (3.1+/-1.11) versus (1.9+/-1.11). Blood hemodilution was demonstrated in the APO group with a decrease of haematocrit by over 10% between the admission and the control value. No other risk factor was found.

CONCLUSION

Tocolysis should be administered at the lowest possible perfusion rate with incremental doses as long as the heart rate stays under 120 beats/min and stopped after 48 h. Administration of maximal 11 of solute perfused/day is recommended. For the patient's follow-up we estimate daily input and output fluid to avoid hydric overload, and a daily control of haematocrit whose variation must be less than 10%.

Sporadic case of dyssegmental dysplasia with antenatal presentation

Dyssegmental dysplasia is a rare micromelic dwarfism with characteristic clinical and radiological features. In skeletal dysplasias with severe micromelia prenatal detection of affected fetuses is possible using ultrasonography. However, prenatal diagnosis is usually performed after the occurrence of a previous case in the family. In this case dyssegmental dysplasia was detected prenatally in the first child of unaffected related (first cousins) parents. Fetal ultrasonographic examination in the 33rd week of gestation revealed a normal biparietal diameter of 94 mm and pronounced shortening of the extremities with femurs of 19 mm. The femurs were bowed. The spine showed severe malsegmentation. At radiological examination the long bones showed a dumbbell configuration especially in the longer extremities. The spine showed severe malsegmentations including coronal and sagittal clefting and multiple outsize vertebrae. The pelvis had very narrow sacrosciatic notches and rounded iliac wings. This case supports the autosomal recessive inheritance and demonstrates the possibility of prenatal diagnosis in non familial cases in this type of micromelic dwarfism.

[Role of the process of endothelium formation on the wall of the aortic prosthesis in protection against infection. Experimental study in dogs]

An experimental canine model was developed in order to evaluate the role of endothelialization of aortic prostheses for protection against septicemic infection and the utilization of 131I radiolabeled bacteria for vascular experimentation. Two groups of dogs were submitted to insertion of a dacron prosthesis segment in the abdominal aorta with subsequent infusion of inert 131I radiolabeled bacteria. In the first group ("A"), formed by five dogs, the infusion was made 30 minutes after the insertion of the prosthesis and in the second group ("B"), formed by four dogs, in a new surgery performed 12 weeks after. Fragments of the animals' prostheses and aortas were collected after 30 minutes of septicemia and analyzed by scan electron microscopy and submitted to reading of radioactivity uptake by a well-type counter. The microscopy recognized a complete endothelialization of the prostheses of dogs of group "B" 12 weeks after their insertion. Statistical analysis comparing fragments of non-endothelialized prostheses, of endothelialized prostheses and aortas demonstrated that the lower radioactivity uptake of the endothelialized prostheses in relation to non-endothelialized ones was significant (p = 0.0143) and that there was no significant statistical difference in uptake in the aortas and in endothelialized prosthesis (p = 0.3173). It was, therefore, concluded that prosthesis endothelialization fully protected them against septicemic infection; bacteremia contaminated all the non-endothelialized prostheses; there was no bacterial adhesion in the endothelialized prostheses and the use of bacteria labeled with radioisotope 131I is appropriate for the study of infections in vascular prosthetic devices.

Plasma active renin, angiotensin I, and angiotensin II during pregnancy and in preeclampsia

OBJECTIVE

To evaluate the activity of the renin-angiotensin-aldosterone system in the circulation during the three trimesters of normal pregnancy and in women with preeclampsia.

METHODS

Normal pregnant volunteers (n = 7) were studied throughout pregnancy, and women with preeclampsia (n = 8) were studied in the third trimester. Plasma active renin and aldosterone were measured by radioimmunoassay. Angiotensin I and angiotensin II were determined by radioimmunoassay after separation of the peptides by high-performance liquid chromatography.

RESULTS

Active renin concentration increased in the first trimester of normal pregnancy, whereas angiotensin I, angiotensin II, and aldosterone remained at a level comparable to the postpartum values. Highest activity of the renin-angiotensin-aldosterone system was observed during the third trimester with increased levels of angiotensin I, angiotensin II, and aldosterone. In contrast, in patients with preeclampsia, despite a slight increase of active renin levels, the other parameters of the renin-angiotensin-aldosterone system were low compared with the third trimester of normal pregnancy and were comparable to postpartum data.

CONCLUSION

Our results suggest that during the first trimester of normal pregnancy, active renin concentration in the plasma is increased and that renin is not the factor that limits angiotensin II synthesis. These results also confirm decreased activity of the renin-angiotensin-aldosterone system in preeclampsia. This could contribute to the diminished hemodynamic control observed in pregnant women developing preeclampsia.

Surgical management of hepatocellular carcinoma: resection or transplantation?

Liver resection or transplantation offers the best opportunity for cure of hepatocellular carcinoma (HCC). To determine the relative roles for resection and transplantation and to evaluate the patient and tumor characteristics that might predict survival, the records of 125 patients treated for nonfibrolamellar HCC at The Toronto Hospital between 1981 and 1996 were reviewed. No adjuvant chemotherapy or antiviral protocols were used. Resection was the first operation in 67 patients; one underwent re-resection. Sixty patients underwent transplantation including two who had previously had a resection; 40 had known or suspected HCC and 20 had incidental tumors identified in the explanted liver. The incidence of cirrhosis was 49% for resection and 88% for transplantation. The incidence of hepatitis B virus (HBV) was 58% and 33%, respectively. The operative mortality rate for resection was 4.4% (9.4% in cirrhotic and 0 in noncirrhotic patients) and 13.3% for transplantation. The 5-year cumulative recurrence rate was 55% following resection and 20% following transplantation (P <0.001). The 5-year Kaplan-Meier survival rates were 38% for resection and 45% for transplantation-60% for transplanted HBV-negative and 17% for HBV-positive patients (P <0.001). After resection, recurrent HCC accounted for 86% of deaths, whereas recurrent HBV was responsible for 42% of deaths after transplantation. By univariate analysis, following resection, vascular invasion, advanced stage, multiple tumors, and lack of a capsule were predictive of survival; cirrhosis, HBV, age, tumor size, number, and grade were not. By multivariate analysis, only vascular invasion was predictive for resection and HBV for transplantation. Resection and transplantation are complementary methods of treating HCC. With the current organ shortage, resection should be considered first-line treatment. HBV-positive patients with HCC should only undergo transplantation in combination with effective antiviral therapy.

[What does the cesarean rate mean in France/]

For more than twenty-five years, the cesarean rate in France, as in other developed countries, has continued to increase, and in 1995 was 15.9%. Cesareans are now taken for granted by the general public, who are usually unaware of their consequences for maternal mortality and morbidity and continue to consider this form of delivery as the safest for the new born child. Yet it has been clearly demonstrated that cesarean deliveries are associated with higher rates of maternal and perinatal morbidity than vaginal deliveries and that they increase maternal mortality by a factor of from 5 to 7. From an economic standpoint, cesareans are between two and three times more expensive than vaginal deliveries. The two main indicators which account for the increase in cesareans are cicatricial uterus and dystocia. These are indicators in which individual practitioners' normal practice and the fear of medical malpractice suits play a clear role. There appears to be a particular correlation between the proportion of cesareans and obstetricians' insurance premiums, obstetricians' own assessment of the risk of malpractice suits and the number of complaints lodged against hospitals or individual doctors. Cesareans performed on grounds of fetal suffering or breech deliveries represent a diminishing proportion of the total. The use of scalp pH and radiopelvimetry have made it possible to restrict the number of cesareans based on these indicators. Other factors play a role in this increase, such as parity, education level, type of maternity insurance, whether the hospital is private or public, whether or not there is a neonatal resuscitation unit, the size of the city and the obstetrician's experience and type of training. The time and day or delivery have also been shown to be relevant factors. For obstetricians themselves, the higher fees earned from cesareans do not appear to be important. Of more relevance is the opportunity they offer doctors to organise their schedule and save time. Among the various methods proposed for reducing the cesarean rate, a strict definition of and respect for the indications for a cesarean, involving comparisons between establishments and between practitioners, have been shown to be effective. To allow such figures to be compiled, France should therefore produce for each confinement a standard record containing the different perinatal data, as is already the case in numerous other countries.

Multicenter study on the clinical value of fetal pulse oximetry. I. Methodologic evaluation. The French Study Group on Fetal Pulse Oximetry

OBJECTIVE

Our purpose was to evaluate the feasibility of intrapartum fetal pulse oximetry, the distribution of fetal oxygen saturation values, and the relationship with the neonatal outcome in a population with an abnormal fetal heart rate.

STUDY DESIGN

A prospective multicenter observational study was performed from June 1994 to November 1995. Fetal oxygen saturation was continuously recorded with use of a Nellcor N-400 fetal pulse oximeter in case of an abnormal fetal heart rate during labor. Simultaneous readings of fetal oxygen saturation and fetal blood analysis were obtained at inclusion and before birth. Feasibility, adverse effects, distribution of fetal oxygen saturation values, and relationship with neonatal outcome were assessed.

RESULTS

One hundred seventy-four patients were included. From 172 attempted sensor placements, the procedure was impossible in three cases and fetal oxygen saturation values were obtained in 164 cases (95.3%). Physicians considered sensor placement an easier task than an attempt at fetal blood analysis (easy in 87.5% vs 78.9% for fetal blood analysis, p = 0.03). The mean reliable signal time (+/- SD) was 64.7% +/- 32% during the first stage. There were no serious adverse effects in the study population. The mean fetal oxygen saturation during the first stage of labor was 42.2% +/- 8.0% (10th to 90th percentile range 30% to 53%). Fetal oxygen saturation was significantly correlated with scalp pH (r = 0.29, p = 0.01) but not with neonatal umbilical artery pH or gas values. There was a significant association between low fetal oxygen saturation (< 30%) and poor neonatal condition.

CONCLUSION

The feasibility of fetal pulse oximetry is satisfactory in clinical practice. It is easy to use and provides a fair rate of recorded values, even in a population with suspicion of fetal distress. A low fetal oxygen saturation is significantly associated with an abnormal neonatal outcome.

Identification of essential amino acids in phenylalanine ammonia-lyase by site-directed mutagenesis

The postulated precursor of the prosthetic dehydroalanine of phenylalanine ammonia-lyase (PAL), serine 202, was changed to cysteine by site-directed mutagenesis. After cloning and heterologous expression in Escherichia coli, the gene product was assayed for PAL activity. Mutant S202C showed full catalytic activity, and its kinetic constants and the amount of thiol groups were identical to those of wild-type PAL. It must be concluded that in a posttranslational modification both water and hydrogen sulfide can be eliminated from the amino acid in position 202 to form dehydroalanine. In an attempt to identify further amino acids essential either for the posttranslational modification or for catalysis, arginine 174, glutamine 425, and lysine 499 were changed to isoleucine. Analysis of the heterologously expressed mutated gene products revealed that only the R174I mutant showed a significantly lower Vmax value (1/450) identifying this arginine as important. This finding was supported by treatment of wild-type PAL and mutant R174I with phenylglyoxal and 2,3-butandione. Both react specifically with the guanidino group of arginine. They irreversibly inhibited wild-type PAL but had no influence of the Vmax value of mutant R174I. Preincubation with l-phenylalanine protected wild-type PAL from inhibition by phenylglyoxal indicating that arginine 174 is close to the active site. Incubation with KCN irreversibly abolished the remaining activity of mutant R174I leading to the conclusion that arginine 174 is important in catalysis.

Multicenter study on the clinical value of fetal pulse oximetry. II. Compared predictive values of pulse oximetry and fetal blood analysis. The French Study Group on Fetal Pulse Oximetry

OBJECTIVE

Our purpose was to compare the predictive value of intrapartum fetal pulse oximetry with that of fetal blood analysis for an abnormal neonatal outcome in case of an abnormal fetal heart rate.

STUDY DESIGN

A prospective multicenter observational study was conducted from June 1994 to November 1995. Fetal oxygen saturation was continuously recorded with a Nellcor N-400 fetal pulse oximeter in case of an abnormal fetal heart rate during labor. Simultaneous readings of fetal oxygen saturation and fetal blood analysis obtained before birth (i.e., either at full dilatation or before cesarean section when indicated) were compared with the neonatal status. The criteria for an abnormal neonatal outcome were (1) an umbilical arterial blood pH < or = 7.15 and (2) a combined variable including 5-minute Apgar score < or = 7, umbilical arterial pH < or = 7.15, secondary respiratory distress, transfer in a neonatal care unit, or neonatal death.

RESULTS

At a 7.20 threshold for fetal scalp pH and 30% for fetal oxygen saturation (i.e., the 10th percentile in the study population), the predictive value of fetal pulse oximetry was similar to that of fetal blood analysis for an arterial umbilical pH < or = 7.15 and for an abnormal neonatal outcome (positive predictive value 56% vs 55%, negative predictive value 81% vs 82%, sensitivity 29% vs 35%, and specificity 93% vs 91%, respectively). The receiver-operator characteristic curve showed similar performance of either technique for cutoff values < or = 7.20 for fetal blood pH and < or = 30% for fetal oxygen saturation, whereas fetal pulse oximetry became superior at higher thresholds.

CONCLUSION

The predictive value of intrapartum fetal pulse oximetry can be favorably compared with that of fetal blood analysis. Randomized controlled management trials can now be performed to assess potential clinical benefits of this new tool.

Antenatal diagnosis of brain damage in the survivor after the second trimester death of a monochorionic monoamniotic co-twin: case report and literature review

At 28 weeks of amenorrhea, 1 fetus of a monoamniotic twin pregnancy died. Ultrasound and Doppler investigations of the surviving twin were normal. Three weeks later, endovaginal ultrasound and magnetic resonance imaging revealed massive bilateral cerebral ischemic necrosis in the surviving twin. In utero fetal blood sampling carried out before the termination did not reveal either anemia or thrombopenia. Current data suggest that cerebral or renal ischemic complications could set in immediately after the death of the first twin as a result of a period of acute hypotension. At least 2 weeks are necessary for them to be identifiable by ultrasound. It seems that they cannot be prevented by prompt delivery of the second twin.