Mucosal immunization of calves with recombinant bovine adenovirus-3: induction of protective immunity to bovine herpesvirus-1

To determine the potential of replication-competent (E3-deleted) bovine adenovirus-3 (BAV-3) as a delivery system for vaccine antigens in calves, we evaluated the ability of recombinant BAV-3 expressing different forms of of bovine herpesvirus-1 (BHV-1) glycoprotein gD to protect against BHV-1 infection in calves that had pre-existing BAV-3 specific antibodies. Three- to four-month-old calves, vaccinated intranasally with recombinant BAV-3 expressing full-length gD (BAV3.E3gD) or a truncated version of gD (gDt) (BAV3.E3gDt), or with E3-deleted BAV-3 (BAV3.E3d; control), were challenged with BHV-1 strain 108. Vaccination with BAV3.E3gD or BAV3.E3gDt induced gD-specific antibody responses in serum and nasal secretions, and primed calves for gD-specific lymphoproliferative responses. In addition, all calves developed complement-independent neutralizing antibodies against BHV-1. Protection against viral challenge was observed in calves vaccinated with recombinant BAV3.E3gD or BAV3.E3gDt as shown by a significant reduction in body temperature and clinical disease, and a partial reduction in the amount and duration of virus excretion in nasal secretions. These results indicate that replication-competent BAV-3-based vectors can induce protective immune responses in calves (the natural host) that have pre-existing BAV-3-specific antibodies.

[Congenital heart abnormalities and cardiac dysfunction: how prenatal diagnosis changed the chances for survival]

Because of the rapid development of sonography, there are many new informations on embryonal and fetal circulation and pathophysiology of decompensation. Echocardiography is a useful tool to follow intrauterine therapy. Authors have examined the effect of prenatal diagnosis on the prevalence of heart abnormalities, terms of cardiac surgery, perinatal mortality and mortality due to heart abnormalities or decompensation. During five years they have found 187 severe heart abnormalities. Because of parental request 90 pregnancies have been terminated. Following prenatal diagnosis in 16 cases planned surgery of the newborn, in 14 cases planned cesarean sections have been done. From 64 transplacentar treatments 44 patients have survived. Authors have found, that prenatal diagnosis had good effect on short term survival rate but had no effect on long term survival rate. Fetal echocardiography has selective and therapeutic effect. The selective effect depends on second trimester screening. The therapeutic effect was significant in cases of arrhythmias and decompensation.

Apolipoprotein E gene polymorphism frequencies in a sample of healthy Hungarians

Apolipoprotein E (apo E) has been found to play an important role in lipid metabolism and has been associated with cardiovascular and neurodegenerative conditions. Hungarians have some of the highest rates of cardiovascular morbidity and mortality in the world. This study examines the distribution of apo E alleles and genotypes in a population of healthy ethnic Hungarian blood donors (n = 302). Male (n = 152) and female (n = 150) subjects ranging from 18 to 62 years of age (mean 37.0) were involved. To determine the frequency of apo E alleles, polymerase chain reaction followed by restriction length polymorphism was applied. The analyses of data showed that apo E allele epsilon3 had the greatest frequency in this group (0.807), followed by apo epsilon2 (0.104) and apo epsilon4 (0.087). The highest genotype frequency was found to be epsilon3/3 at 65.2% (n = 197) followed by genotype epsilon3/4 at 15.9% (n = 48), genotype epsilon2/3 at 15.2% (n = 46), genotype epsilon2/2 at 2.3% (n = 7), genotype epsilon2/4 at 1.0% (n = 3) and genotype epsilon4/4 at 0.4% (n = 1). The apo E frequencies found in this study appear to differ from an earlier study of blood donors, where the results are based on apo E phenotyping.

The effect of pre-existing adenovirus-specific immunity on immune responses induced by recombinant adenovirus expressing glycoprotein D of bovine herpesvirus type 1

We investigated whether pre-existing adenovirus-specific immunity influenced the development of immunity to a foreign antigen expressed by recombinant adenovirus. Active adenovirus-specific immunity was induced in cotton rats by i.n. administration of wild type human adenovirus type 5 (HAd5) two weeks before immunisation with a HAd5 vector expressing the glycoprotein D (gD) of bovine herpesvirus type 1 (gD-dE3 recombinant adenovirus). Active adenovirus-specific immunity inhibited gD-specific immune responses, following either i.n. or gastrointestinal immunisation with gD-dE3. An inhibitory effect was present even if infection with HAd5 and immunisation with gD-dE3 were 13 weeks apart. Passive transfer of adenovirus specific antibodies to cotton rats one day before immunisation, however, did not significantly inhibit gD-specific immune responses induced by i.n. immunisation with gD-dE3. Repeated administration of an adenovirus vector, therefore, may have a limited ability to deliver antigen, while passive immunity to adenovirus may not interfere with the success of immunisation.

Hyperreactio luteinalis in a normal singleton pregnancy. A case report

BACKGROUND

Hyperreactio luteinalis rarely occurs in normal singleton pregnancy. About 50 such cases have been published. This case is noteworthy because it resulted in extremely enlarged ovaries and was accompanied by a hyperandrogenic state and high level of human chorionic gonadotropin.

CASE

A gravida was referred to our department because of large, bilateral, cystic ovaries diagnosed by ultrasonography in the 28th week of gestation. Markedly elevated levels of androgens and human chorionic gonadotropin were noted. During the following six weeks the ovarian masses enlarged, and the hyperandrogenic state worsened. Cesarean section and, because of a bleeding right adnexectomy, left ovarian resection were performed. Histology confirmed the presumed diagnosis of hyperreactio luteinalis. The placenta was unremarkable. Seventeen weeks after surgery the hormone levels were normal.

CONCLUSION

Our case suggests the possibility that in certain cases of hyperreactio luteinalis, an idiopathic elevation of human chorionic gonadotropin, can occur even in normal singleton pregnancies. Furthermore, it calls attention to the necessity of ultrasonographic demonstration of ovaries even during late pregnancy.

Calcification of the fetal heart--four case reports and a literature review

Calcification of the heart and vessels in fetuses is a rare condition. It may be dystrophic or metastatic. An extremely rare form of vascular calcification has been termed 'idiopathic arterial calcification of infancy', which is inherited in an autosomal recessive pattern. We report four cases of myocardial calcifications of different origin diagnosed in utero. The correct diagnosis is very important in regard to genetic counselling.

Induction of immunity in the respiratory tract and protection from bovine herpesvirus type 1 infection by different routes of immunization with recombinant adenovirus

To investigate the capability of different routes of immunization with replication-competent recombinant adenovirus to induce antigen-specific antibody responses, we immunized cotton rats with a human adenovirus type 5 (HAd5) vector expressing the glycoprotein D (gD) of bovine herpesvirus type 1 (BHV-1) (gD-dE3). Different routes of mucosal and systemic immunization (intraduodenal-oral, intraduodenal, intranasal and intradermal) with gD-dE3 stimulated similar levels of gD-specific IgG in the serum of cotton rats. However, intranasal (i.n.) immunization stimulated higher levels of gD-specific IgA in the lung and nasal washes, and higher frequency of gD-specific antibody secreting cells in the lung than did the intradermal immunization. Higher levels of antibody in the respiratory tract following i.n. immunization correlated with better protection of the lungs against i.n. BHV-1 challenge. Intraduodenal-oral immunization induced more gD-specific antibodies in the respiratory tract than intraduodenal immunization alone. Adenovirus dissemination to most organs tested was evident following each route of immunization, which is important to consider when studying the mechanism of induction of immunity by recombinant adenoviruses.

Prenatal detection of trisomy 13 from amniotic fluid by quantitative fluorescent polymerase chain reaction

Prenatal diagnosis of fetal trisomies is usually performed by cytogenetic analysis from amniotic fluid. However, this requires lengthy laboratory procedures, high costs and is unsuitable for large-scale screening of pregnant women. An alternative method, which is rapid, inexpensive and suitable for diagnosing trisomies, even from single fetal cells, is the fluorescent polymerase chain reaction (PCR) using polymorphic small tandem repeats (STRs). In this paper, we present the method of rapid prenatal detection of trisomy 13 from amniotic fluid using fluorescent PCR and two highly polymorphic STRs (D13S258 and D13S631). The results obtained by quantitative fluorescent PCR amplification of fetal DNA were concordant with amniocyte karyotyping results in all cases. Two cases of trisomy 13 were detected from 212 amniotic fluids and the results obtained from D13S631 and D13S258 amplification are presented. In the first trisomy 13 case, a triallelic pattern was detected by both markers, and in the second case, D13 markers showed a characteristic 2:1 dosage allele ratio, both of which demonstrate trisomy 13 status. All other heterozygous disomic samples showed an allele intensity ratio of 1:1.

Fetal hydropericardium associated with left ventricular diverticulum

Fetal pericardial effusion usually develops because of fetal heart failure, infections, chromosomal abnormalities, fetal anaemia, intracardiac or extracardiac tumours. There is only one case in the literature of isolated hydropericardium associated with left ventricular diverticulum and here we report another.

Central nervous system anomalies

The authors review the most common congenital anomalies of the central nervous system (CNS): neural tube defects (NTDs), ventriculomegaly/holoprosencephaly, hydranencephaly, holoprosencephaly sequence, iniencephaly, and microcephaly. They emphasize the importance of the diagnostic tools (biochemical markers of the maternal serum, ultrasound screening, invasive techniques), methods which are complementary to each other.

Quality assurance in obstetric and gynecologic ultrasound. The Hungarian model

The majority of physicians performing obstetric scans are radiologists and obstetricians. The radiologist is well trained in imaging but lacks the obstetric background required to interpret information obtained from the scan. The obstetrician is qualified in obstetric knowledge but often lacks the formal imaging training necessary to optimize the pictures. In Hungary, nearly 100% of the physicians who perform obstetric and gynecologic scans are obstetricians. In order to create a standard and to hold together the practitioners in obstetrics and gynecology, as well as to eliminate the serious consequences of clinical malpractice, we organized the Hungarian Society of Ultrasound in Obstetrics and Gynecology in 1992. The Society was established according to the standards of the most skilled obstetricians and gynecologists. In addition to working out the conditions and the standards, the Society provides for its members continuous education, postgraduate training, and monitors the knowledge and level of practitioners. We have established three levels of qualification. Each level requires a medical undergraduate degree. The levels range from basic (A), intermediate (B), to specialist (C). To receive the certificate every user and ultrasound laboratory have to fulfill requirements based on skill as well as equipment and circumstances. The certificates are valid for one year. Every year the practitioner must pass a special examination at the appropriate level. By doing so, the Society provides its members with not only professional support, but ethical and legal security as well.

Optimization of kinoform lenses with the Monte Carlo method

For the optimization of non-Fourier-type computer-generated phase holograms (kinoform lenses), a method based on the Monte Carlo procedure is suggested. This method can be regarded as analogous to the iterative Fourier transform algorithm method that is widely used for the optimization of Fourier-type computer-generated phase holograms (kinoforms).

Same day diagnosis of Down's syndrome and sex in single cells using multiplex fluorescent PCR

The major reason for prenatal diagnosis lies in the detection of trisomies, particularly trisomy 21 (Down's syndrome). Current techniques require lengthy laboratory procedures and high costs. Furthermore, diagnosis is often not possible if the sample is of small size or is contaminated. An alternative method, quantitative fluorescent polymerase chain reaction (PCR) of short tandem repeats (STRs), can also be used to diagnose trisomies and it has the advantage that a result is obtained within five to eight hours. However, this method is currently limited to relatively large amounts of sample, which restricts diagnostic confidence and value. Recently, genetic diagnosis using fluorescent PCR has been applied at the single cell level but is limited to sex or single gene defect diagnosis. This study, using quantitative multiplex fluorescent PCR, provides for the first time simultaneous diagnosis and confirmation of sex and trisomy in single cells. Two markers for chromosome 21 increase diagnostic confidence, informativeness, and confirmation. This system is rapid (five hours), reliable, and accurate and we believe that it will be more cost effective than alternative methods. The technique has direct application to preimplantation genetic diagnosis, early prenatal diagnosis, and other diagnostic systems where sample size is limited.

Detection of factor V Leiden mutation in severe pre-eclamptic Hungarian women

Pre-eclampsia is a pregnancy-related disorder that complicates approximately 5% of all pregnancies and is cited as the primary cause of worldwide maternal and fetal mortality. The factor V Leiden mutation has been implicated in the development of severe pre-eclampsia. In order to investigate this association, a sample of 198 Hungarian women was recruited and enrolled in one of the three groups based on reproductive and health status: those as classified as pregnant and healthy (n = 71), those diagnosed as pregnant and severe pre-eclamptic (n = 69), and those found to be healthy and non-pregnant (n = 58). The presence of factor V Leiden mutation was determined by using polymerase chain reaction (PCR) followed by restriction fragment length polymorphism analysis (RFLP). We identified three (5.2%) heterozygous among healthy non-pregnant participants, five (7.0%) heterozygous among healthy pregnant participants and 13 (18.8%) heterozygous among pre-eclamptic women (p < 0.05, 95% CI). Our result supports the previous observation that carriers of factor V Leiden mutation are at increased risk for developing severe pre-eclampsia.

Intracellular calcium and electrical restitution in mammalian cardiac cells

The role of calcium current and changes in intracellular calcium concentration ([Ca2+]i) in regulation of action potential duration (APD) during electrical restitution process was studied in mammalian ventricular preparations. Properly timed action potentials were recorded from multicellular preparations and isolated cardiomyocytes using conventional microelectrodes and EGTA-containing patch pipettes. APD increased monotonically in canine and guinea pig ventricular preparations with increasing diastolic interval (DI), while in rabbit papillary muscles the restitution process was biphasic: APD first lengthened, then shortened as the DI increased. When the restitution process was studied in single cardiomyocytes using EGTA-containing patch pipettes, the restitution pattern was similar in the three species studied. Similarly, no difference was observed in the recovery time constant of calcium current (/Ca-L) measured under these conditions in voltage clamped myocytes. Loading the myocytes with the [Ca2+]i-chelator BAPTA-AM had adverse effects in rabbit and canine cells. In rabbit myocytes steady-state APD lengthened and the late shortening component of restitution was abolished in BAPTA-loaded cells. In canine myocytes BAPTA-load shortened steady-state APD markedly, and during restitution, APD decreased with increasing DI. The late shortening component of restitution, observed in untreated rabbit preparations, was greatly reduced after nifedipine treatment, but remained preserved in the presence of 4-aminopyridine or nicorandil. Beat to beat changes in APD, peak/Ca-L and [Ca2+]i, measured using the fluorescent dye, Fura-2, were monitored in rabbit ventricular myocytes after a 1-min period of rest. In these cells, the shortening of APD was accompanied by a gradual reduction of the peak/Ca-L and elevation of diastolic [Ca2+]i during the initial eight post-rest action potentials. It is concluded that elevation of [Ca2+]i shortens, while reduction of [Ca2+]i lengthens APD in rabbit, but not in canine ventricular myocytes. These differences may probably be related to different distributions of [Ca2+]i-dependent ion currents and/or to differences in calcium handling between the two species.

[Prenatal diagnosis of tricuspid atresia]

Tricuspid atresia is the third most common cyanotic cardiac malformation, seen in 1 per cent of children with congenital heart disease. It occurs in 4-5 per cent of congenital heart defects diagnosed prenatally, this difference is a consequence of a high percentage of intrauterine death these severely ill fetuses. Initial surgical treatment is palliation, usually with aortopulmonary shunt. Definitive treatment is the Fontan operation, when the systemic venous return is connected directly to the pulmonary tree. Five-year survival for liveborn patients is 50, but for prenatally diagnosed fetuses only 20%. In Hungary there is only a few survivor. Authors have diagnosed 20 tricuspid atresias during a five-year period by fetal echocardiography. In two cases the postnatal findings were: normal tricuspid valves, univentricular atrio-ventricular connection and stenosis of the pulmonary artery, in one case dysplastic tricuspid valves, hypoplastic right ventricle and stenosis of the pulmonary artery. Authors summarise their experiences with prenatal echocardiography of tricuspid atresia and describe characteristic signs could be found by routine ultrasound screening of this severe cardiac malformation.

[Fetal atrioventricular septal defect associated with Patau and Edwards syndromes, as well as trisomy 22]

The atrioventricular septal defect is usually associated with trisomy 21 and it may be observed in the heterotaxia syndromes. Atrioventricular septal defect may be associated with 8p deletion. There are reported cases of familial atrioventricular septal defect. Atrioventicular septal defect is rarely associated with other chromosomal abnormalities. We are reporting three unusual cases of atrioventricular septal defect that were associated with trisomy 13, 18 and 22. This association may be due to effect of genetic loci on the 13, 18 and 22 chromosome which could play the role in the development and fusion of endocardial cushion and atrioventricular septal defect.

Rapid trisomy diagnosis (21, 18, and 13) using fluorescent PCR and short tandem repeats: applications for prenatal diagnosis and preimplantation genetic diagnosis

PURPOSE AND METHODS

Prenatal diagnosis of fetal trisomies is usually performed by cytogenetic analysis from amniotic fluid. This requires lengthy laboratory procedures and high costs and is unsuitable for large-scale screening of pregnant women. An alternative method, which is rapid and inexpensive and may potentially be suitable for diagnosing trisomies even from single fetal cells, is the fluorescent polymerase chain reaction (F-PCR) using polymorphic small tandem repeats (STRs).

RESULTS

In this paper we present data demonstrating that fluorescent PCR amplification of STRs can be used for rapid diagnosis of trisomy 21, trisomy 18, and trisomy 13 and can be successfully applied to both prenatal diagnosis and diagnosis of single cells. This study also reports significant numbers of prenatal diagnoses using quantitative fluorescent PCR.

CONCLUSIONS

We believe that further studies of greater numbers of samples will determine the absolute reliability of this technique. These results also provide a model for trisomy diagnosis from single cells using multiple STR markers for either preimplantation genetic diagnosis or, potentially, diagnosis from fetal cells isolated from maternal blood.

Serological responses of patients with ectopic pregnancy to epitopes of the Chlamydia trachomatis 60 kDa heat shock protein

Clinical and histopathological correlations of immunoreactivity to Chlamydia trachomatis and to epitopes of the C. trachomatis 60 kDa heat shock protein (hsp60) among women with ectopic pregnancy were evaluated in a case-control study. Serological responses to 13 synthetic peptides corresponding to major epitopes of the chlamydial hsp60 were determined in 67 women treated for ectopic pregnancy and 45 women with uncomplicated pregnancy in utero. Plasma cell salpingitis was detected in 29 (43.3%) of the ectopic patients. Its presence correlated with antibodies to two hsp60 epitopes, encompassing amino acids 260-271 and 411-422 (P = 0.02). Antibodies to these two epitopes, along with five other epitopes, also correlated with peritubal adhesion formation in ectopic pregnant patients (P < 0.01). Antibodies to epitopes 260-271 and 188-199 also correlated with a history of pelvic inflammatory disease (PID; P = 0.05). Patients with ectopic pregnancy were also more likely than their intrauterine pregnant controls to have present anti-chlamydial immunoglobulin G (P < 0.005). Women positive for both C. trachomatis and hsp60 epitope antibodies had an increased prevalence over controls of salpingitis, pelvic adhesions or history of PID (P < 0.05). In contrast, patients who were positive for only C. trachomatis antibodies or only hsp60 epitope antibodies did not differ from antibody-negative patients in each of these categories.

[Severe left heart developmental disorder and severe fetal arrhythmia in the same family--a coincidental association?]

The etiology, pathogenesis and risk for inheritance of congenital heart abnormalities are important questions. The development of fetal echocardiography and fetopathology helped in examination of this problem. Between September 1992 and June 1997 there were found four families where one member of the family had hypoplastic left heart syndrome and other member sustained fetal arrhythmia. The familiarity of hypoplastic left heart syndrome and some special forms of arrhythmias are well known. The reported familial association of these two abnormalities which in the first in the literature, may have a possibility that a sustained ectopic atrial arrhythmias are as severe risk factors for left heart abnormalities as other left heart abnormalities are.

Estimate of the annual per capita surplus dose due to the elevated indoor exposure to 222Rn progeny caused by the use of slag and spoil of uranium rich coal for building purposes in Ajka Town, Hungary

Ajka is a mining and industrial town in Hungary. Brown coal rich in uranium (300 to 900 Bq kg(-1)) has been mined by the town since 1865. Slag and spoil of the coal were frequently used in the town for building purposes before 1960. Screening measurements of 222Rn progeny in indoor air were performed in 86 Ajka buildings. Elevated 222Rn progeny levels were found in houses that used the above by-products as building materials or foundations. Annual per capita surplus effective doses due to the exposure to elevated 222Rn progeny levels were estimated from the results of the screening measurements. The possibility of estimating the mean of the annual averages of 222Rn or 222Rn progeny concentration for a group of houses from the results of screening measurements is discussed in detail. The estimated annual surplus dose is 0.64 mSv for the population of the whole town and 1.86 mSv for the 7,000 occupants of family houses built before 1960.

Calcium-activated transient membrane currents are carried mainly by chloride ions in isolated atrial, ventricular and Purkinje cells of rabbit heart

Under physiological conditions, calcium-dependent ([Ca2+]i-dependent) Cl- currents (ICl(Ca)) have been suggested to participate in the repolarizing processes. In this paper, the possible contribution of ICl(Ca) to transient inward currents and, hence to arrhythmias, has been studied in myocytes from the working myocardium and from the conductive system. Single atrial, ventricular and Purkinje cells, isolated enzymatically from rabbit heart, have been studied under whole-cell voltage-clamp and were internally perfused with the fluorescent Ca2+ indicator, fura-2 (100 microM). Ca2+ release from the sarcoplasmic reticulum was either induced by external application of caffeine or occurred spontaneously in Ca(2+)-overloaded cells. Membrane currents accompanying Ca2+ transients showed linear current-voltage characteristics between -60 and +80 mV as evidenced from fast voltage ramps. When intra- and extracellular Cl- concentrations were kept symmetrical in the absence of the Na(+)-Ca2+ exchange mechanism, transient currents had a reversal potential close to 0 mV. Reduction of external Cl- concentration shifted this reversal potential towards the new Cl- equilibrium potential. Neither the time course of the transient currents nor the shift in their reversal potentials was significantly affected by the presence of Na+. Approximately 90% of this current was blocked by the application of the Cl- channel blocker, anthracene-9-carboxylic acid (0.5 mM) at +80 mV. It is concluded, that [Ca2+]i-activated transient membrane currents in atrial, ventricular and Purkinje cells of rabbit heart are mainly due to the activation of a [Ca2+]i-dependent Cl- current.

[Incidence and mortality of extrauterine pregnancy in Hungary (1931-1995)]

The authors report on the changing incidence of and maternal mortality from ectopic pregnancies in Hungary between 1931 and 1995. Data of reported pregnancies were obtained from the National Institute of Statistics and the Hungarian College of Obstetricians and Gynecologists. Incidence of ectopic pregnancy was calculated as rates per 1000 live births and per 1000 reported pregnancies including live births, legally induced abortions, miscarriages, and ectopic pregnancies. Ectopic pregnancy-associated maternal mortality was examined in terms of case fatality rate and also as a proportion to the total number of pregnancy-associated maternal deaths. From 1931, when national surveillance for pregnancy begun in Hungary, to 1995, the rate per 1000 reported live births tripled from 3.4 to 11.9. Similarly, the rate of ectopic pregnancies per 1000 reported pregnancies increased by 190% from 3.7 to 6.4. In the last decade of the period studied, its proportion in the annual number of fetal deaths increased to 8.0%. Ectopic pregnancy-associated maternal deaths decreased sharply from 1931 through the late 1980's. In the last decade, its average value was 16 per 10.000 reported ectopic pregnancies. However, case fatality rate of ectopic pregnancy is still highest compared to any of the other obstetric events including induced and spontaneous abortions, and deliveries. Over the last decade, maternal deaths resulting from ectopic gestation represented 8.7% of the total maternal mortality rate. Given the increasing incidence of ectopic pregnancy together with a substantial proportion in pregnancy-related maternal mortality, study of etiology, and appropriate preventive measures are urgently needed.

Fetal RhD genotyping by analysis of maternal blood. A case report

BACKGROUND

Prenatal determination of fetal rhesus D (RhD) status is desirable in pregnancies in sensitized, RhD-negative women to prevent hydropic degeneration of the fetus. Recently, a polymerase chain reaction (PCR) test on amniocytes or chorionic villi has been in use to demonstrate the RhD status of the fetus in sensitized pregnancies. A more advisable, noninvasive approach is to determine the fetal RhD group from fetal cells circulating in maternal blood.

CASE

We report on a prenatal diagnosis where RhD-positive cells could be detected from peripheral blood of a sensitized, RhD-negative mother. The presence of an RhD-positive fetus was confirmed by subsequent amplification of fetal DNA obtained by chorionic villus biopsy.

CONCLUSION

In sensitized pregnancies, the number of fetal cells in maternal blood seems to be high enough to be detected by PCR in every case.

Detection of mtDNA deletion in Pearson syndrome by two independent PCR assays from Guthrie card

Pearson syndrome is a multisystem juvenile condition associated with deletions in the mitochondrial genome. The most common 4977 bp deletion of mitochondrial DNA (mtDNA) can mainly be detected in the patients' peripheral blood. Here we report a child with a clinically unclarified diagnosis where molecular genetic results proved Pearson syndrome from stored dried blood sample 6 months after the patient's death. PCR amplification around the breakpoint of the most common mtDNA deletion could detect the presence of mutated mtDNA. Another polymerase chain reaction (PCR) assay indicated the low level of wild type mtDNA in patients' blood. We believe that this case shows the importance of storing Guthrie card and the availability of detection of Pearson syndrome from dried blood sample.

[Fetal myocardial calcification (report of 4 cases and review of the literature]

(Report of four cases and review of the literature) Calcification of the myocardium is a rare condition. The cause may be dystrophic or metastatic. An autosomal recessive inherited idiopathic arterial calcification of infancy is more rare abnormality. A dystrophic calcification is the more common of the three and may occur in areas of necrosis, hemorrhage, or fibrosis of the myocardium. Metastatic calcification is associated with hyperparathyroidism, D hypervitaminosis or renal failure, usually accompanied by the deposit of calcium in other organs, particularly the lungs, stomach, kidneys, spleen and liver. Authors report four cases of myocardial calcification diagnosed in intrauterine life. They give a review of literature of fetal and neonatal myocardial calcification.

Low-dose spiral computed tomography of the thorax: comparison with the standard-dose technique

RATIONALE AND OBJECTIVES

This study was conducted to determine whether significant reduction in radiation dose (250 mAs-->50 mAs), in chest computed tomography (CT) using volume acquisition affects image quality or the detectability of pathologic findings in the lung and mediastinum.

METHODS

Phantom studies were conducted to evaluate resolution and noise level, then a patient study was then done. Fifty consecutive patients (10 normal and 40 abnormal) cases were examined. After a scan (250 mAs, 120OkVp) of the entire thorax, five additional slices (50 mAs, 120kVp) at the level of the abnormality were obtained. Three independent observers evaluated the visibility of normal lung and mediastinal structures, as well as image noise. The mean score was compared between the standard and low doses. In a second study, an independent evaluation of the presence or absence of pathologic findings was made by four observers.

RESULTS

Lucite phantom studies demonstrated diminished low-contrast resolution and increased noise level for the low-dose technique. Observers assessed more noise in the low-dose images (P < 0.001). The normal structures were judged to be more visible with standard dose (P < 0.01), but the magnitude of the judged differences was small especially in the lung. No differences were found in the detection of lung and mediastinal abnormalities (P > 0.10).

CONCLUSIONS

The low-dose technique was effective in demonstrating pathologic findings for the lung and mediastinum. Low-dose spiral CT should be considered as a viable alternative to standard-dose spiral CT.

Rapid determination of trisomy 18 parental origin using fluorescent PCR and small tandem repeat markers: case reports

Trisomy 18 is the second most common genetic defect after trisomy 21, almost 90% of which are due to additional chromosome from the mother. The parental origin of the additional chromosome can, if required, be determined by two methods: karyotyping, which takes several weeks; or, more recently, by polymerase chain reaction (PCR) which is often problematic. Fluorescent PCR of small tandem repeats (STRs) can determine the parental origin in the majority of cases within 5 h. Although the incidence of paternal origin is known for both trisomy 21 and trisomy 18, this technique can rapidly determine the parental origin in cases where there is insufficient samples to perform conventional tests. Determining parental origin by these methods may also have clinical significance in the diagnosis of chromosomal translocations or in the diagnosis of genetic disease using linkage analysis.

Prenatal detection of trisomy 21 and 18 from amniotic fluid by quantitative fluorescent polymerase chain reaction

Prenatal diagnosis of fetal trisomies is usually performed by cytogenetic analysis on amniotic fluid. This requires lengthy laboratory procedures and high costs, and is unsuitable for large scale screening of pregnant women. An alternative method, which is both rapid and inexpensive and suitable for diagnosing trisomies even from single fetal cells, is the fluorescent polymerase chain reaction using polymorphic small tandem repeats (STRs). In this paper we present the preliminary results of a larger study comparing parallel prenatal diagnoses of trisomies 21 and 18 using cytogenetics with quantitative fluorescent polymerase chain reaction using STR markers. The results obtained by the two techniques were concordant in all cases. This is the first study reporting significant numbers of prenatal diagnoses using the quantitative fluorescent polymerase chain reaction. We believe that further studies on greater numbers of samples will determine the absolute reliability of this technique. These results also provide a model for diagnosis of trisomy from single fetal cells isolated from maternal blood.

[Prenatal diagnosis of atrioventricular septal defect and its prognostic significance]

Atrioventricular septal defect also known as endocardial cushion defect is severe congenital heart disease which is often associated with chromosomal abnormalities (30-50%) or is a part of a malformation syndrome (30%). Between 1, october 1992, and 30, september 1996. 21 cases were diagnosed prenatally. The chromosomal analysis found in 1 case trisomy 18, in 1 case trisomy 22 and in 7 cases trisomy 21. In 7 cases atrioventricular septal defect was part of Ivemark syndrome, none of them had chromosomal abnormality, except 1, who had trisomy 18. Out of 21 cases there was only one survivor. None of cases associated with Ivemark syndrome survived. In 4 cases sibs or parents had congenital heart disease. Four mother were above 40 years. The report summarises the most important abnormalities in the prenatal diagnosis of endocardial cushion defect and echocardiographic and embryopathologic foundings.

Presymptomatic diagnosis of familial colon polyposis

The gene responsible for familial adenomatous polyposis (FAP) has recently been mapped, identified and this makes the presymptomatic molecular diagnosis of the disease possible. It can be performed by direct mutation analysis or indirect haplotype analysis. In families where several affected individuals are available the indirect haplotype analysis is the easiest way for performing presymptomatic diagnosis of persons at risk. Among Hungarian families we have performed haplotype analysis using D5S346, a highly polymorphic dinucleotide CA repeat marker located 30-70 kb downstream from APC gene with the combination of restriction endonuclease Rsal site polymorphism. Marker regions were amplified by polymerase chain reaction (PCR) and basen on the above-mentioned polymorphic systems, the haplotype at the APC locus was determined. We believe that haplotype analysis of individuals at risk in large FAP families containing several affected members is a rapid, efficient, and highly valuable method for presymptomatic diagnosis of familial colon polyposis.

Ventriculomegaly with radial and renal defects: prenatal diagnosis in two consecutive sibs

We describe two consecutive mid-trimester fetuses of different sexes with identical anomalies of the upper limbs and the kidneys in association with severe ventriculomegaly. We compare this apparently autosomal recessive syndrome to VACTERL-H association, Fanconi anemia, and two other, so far unparalleled syndromes. Taking into account the absence of chromosome breaks, the associated changes of the amniotic fluid, and the renal histology, we conclude that we are dealing with a different entity.

[Complex screening of family members at risk for familial adenomatous polyposis]

151 members of 10 affected families with FAP have been registered at the authors' regional polyposis registry, among them 51 FAP patients were verified histologically. The disorder is autosomal dominant thus the chance for the inheritance of the mutated allele is fifty percent in the offspring of an affected patient. Because of the high risk the registration and regular control of family members is recommended. They can be divided into high risk and low risk group based on presymptomatic tests. The examination of retina pigmentepithel was the only possibility for presymptomatic diagnosis earlier. After localization and identification of APC gene responsible for the disease molecular genetic methods have been introduced for presymptomatic diagnosis. The authors performed presymptomatic tests based on ophthalmologic and molecular genetic methods among family members at risk. Ophthalmologic examination was done in 53 while molecular genetic investigation in 54 cases. All the results of endoscopic, ophthalmological and molecular genetic examinations were available in 35 persons, among them 19 FAP have been found. Ophthalmological examination were informative in 33 out 35 cases (unequivocal positive or negative) while results of molecular genetic methods and sigmoidoscopy were correlated in every case. Authors stress the significance of complex screening of affected families with FAP in the prevention of colorectal cancer and extracolonic malignant processes.

Direct determination of 90Sr and 147Pm in Chernobyl hot particles collected in Kiev using beta absorption method

59 hot particles were collected in Kiev, Ukraine, in 1987. All but one were prepared from a moss carpet of 360 cm2 area. Radionuclide composition of the hot particles was investigated by gamma-spectrometry and beta absorption method. Pure beta emitters 90Sr and 147Pm were determined in 25 hot particles measuring the beta absorption curves of the hot particles with an end-window Geiger-Müller counter and decomposing the curves in order to obtain the contributions of 90Sr and 147Pm to the total beta counting rate. All but one of the hot particles were found to be the debris of the fuel. The activity ratio 90Sr:l44Ce was 0.052 in good agreement with theoretical calculations on core inventories. This means that strontium behaved as a nonvolatile element in the process of the formation of the hot particles investigated. The activity ratio 147Pm:144Ce was 0.078 which is half of the theoretical result. Although 147Pm is considered to be a refractory nuclide, it seems that significant part of 147Pm went to the homogeneous fraction of the general fallout. The surface density of hot particles (of higher than about 50 Bq activity) was about 1,600 m(-2) and that of the activities of the nuclides 90Sr, 106Ru, 134Cs, 137Cs, 144Ce and 147Pm as components of hot particles was 12.2, 54.3, 5.9, 9.7, 234 and 18.3 kBq m(-2) (activity values counted for 26 April 1986), respectively, in downtown Kiev city in 1987.

Mucosal immunization with recombinant adenoviruses: induction of immunity and protection of cotton rats against respiratory bovine herpesvirus type 1 infection

To facilitate the evaluation of vaccines against bovine herpesvirus type 1 (BHV-1), a cotton rat model of intranasal (i.n.) BHV-1 infection was established. Cotton rat lung cells were similar to bovine cells in their ability to support BHV-1 replication in vitro. Furthermore, i.n. inoculation of cotton rats with BHV-1 resulted in pulmonary lesions comparable to BHV-1 infection in cattle. Using this model, the potential of i.n. and gastrointestinal (g.i.) immunization was examined with recombinant human adenoviruses expressing glycoprotein D (gD) of BHV-1 to induce protective immunity against BHV-1. The replication-competent virus (gD-dE3) was more efficient than the replication-defective virus (gD-dE1E3) in inducing gD-specific antibody in the serum and in the respiratory tract. Furthermore, i.n. immunization with gD-dE3 stimulated antigen-specific antibody-secreting cells in the lung 12 weeks following immunization. Protection against BHV-1 challenge correlated with gD-specific antibody levels such that i.n. immunization with gD-dE3 conferred complete protection, while g.i. immunization conferred only partial protection of the lungs of most animals against BHV-1 challenge. In comparison, immunization with gD-dE1E3 by either route resulted in only a partial reduction of BHV-1 titre in the respiratory tract. The results obtained demonstrate that mucosal immunization with replication-competent recombinant adenovirus expressing gD of BHV-1 can induce immunity and protection against BHV-1 challenge.

Kinetics of contractile activation in voltage clamped frog skeletal muscle fibers

Excitation-contraction coupling events leading to the onset of contraction were studied in single skeletal frog muscle fibers. This entailed the simultaneous measurement of the changes in intracellular calcium concentration using antipyrylazo III and fura-2, isometric force, and clamp voltage in a modified single vaseline gap chamber for the first time. The calcium transients were incorporated into an analysis of calcium binding to regulatory sites of troponin C (TnC) that permitted both a linear and a cooperative interaction. The analysis assumed that the onset of mechanical activation corresponds with a particular TnC saturation with calcium setting constraints for the calcium binding parameters of the regulatory sites. Using a simple model that successfully reproduced both the time course and the relative amplitudes of the measured isometric force transients over a wide membrane potential range, k(off) of TnC was calculated to be 78 s(-1) for the cooperative model at 10 degrees C. Together with the above constraints this gave a dissociation constant of 8.8 +/- 2.5 microM and a relative TnC saturation at the threshold (Sth) that would cause just detectable movement of 0.17 +/- 0.03 (n = 13; mean +/- SE). The predictions were found to be independent of the history of calcium binding to the regulatory sites. The observed delay between reaching Sth and the onset of fiber movement (8.7 +/- 1.0 ms; mean +/- SE, n = 37; from seven fibers) was independent of the membrane potential giving an upper estimate for the delay in myofilament activation. We thus emerge with quantitative values for the calcium binding to the regulatory sites on TnC under maintained structural conditions close to those in vivo.

Obstetric anaesthesia in Hungary

A nation-wide survey of pain relief in childbirth in Hungary was carried out in 1993. Information was provided on 104 137 deliveries in 98 units. The frequencies of different methods of pain relief for vaginal delivery were as follows: systemic opiates in 7387 cases (8.3%), epidural analgesia in 4611 cases (5.2%) and inhalational analgesia (nitrous oxide) in 4470 cases (5%). Epidural analgesia was available in 36 units (36.7%). For 71 744 vaginal deliveries (80.5%) no pain relief was provided at all. For caesarean section (n = 13240) the rate of spinal or epidural anaesthesia was 36.7%. It was concluded that despite an increasing rate of pain relief in labour elsewhere, the numbers of epidurals are still rather low in Hungary.

[Management of hemodynamically significant fetal arrhythmias]

Between January 1, 1993, and April 30, 1996, authors treated 23 fetuses with severe rhythm disturbances in their Department. The correct diagnosis was made by fetal echocardiography. They had 15 tachyarrhythmic and 8 bradyarrhythmic patients. They found hydrops fetus at 7 patients because of atrial flutter (2 fetuses), supraventricular tachycardia (4 fetuses) and severe bradycardia (1 fetus). They treated successfully 13 patients with antiarrhythmic therapy given to the mother. They had 1 intrauterine death (treated because of bradycardia) and 1 neonatal death (hydropic because of supraventricular tachycardia). The causes of severe bradycardia were maternal antibody (3 fetuses), cardiac malformation (3 fetuses) and large number of blocked atrial extrasystoles. The prognosis of fetal tachycardia is good even in cases of fetal hydrops. The prognosis of bradycardia due to heart abnormalities is poor.