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R Boos

Publications and source records attributed to R Boos.

At least 19 recordsLinked to original sources
PubMed2005

In-field measurements of PCDD/F emissions from domestic heating appliances for solid fuels.

Within this project the emissions into the atmosphere of polychlorinated dibenzo-p-dioxins and -furans (PCDD/F) of 30 domestic heating appliances in Austrian households were tested. The appliances were single stoves (kitchen stove, continuous burning stove and tiled stove) and central heating boilers for solid fuels up to a nominal heat input of 50 kW. A main objective of this survey was to determine the PCDD/F emissions of domestic heating units under routine conditions. Therefore, the habitual combustion conditions used by the operators were not influenced. The original fuels and lightning supports were used and the operation of the units was carried out by the householders according to their usual practice. The data obtained were used to calculate in-field PCDD/F-emission factors. Most of the appliances have shown PCDD/F emissions within a concentration range of 0.01-0.3 ng TEQ/MJ. Modern fan-assisted wood heating boilers with afterburning and units for continuously burning of wood chips and wood pellets had the lowest emissions. High emissions were caused by unsuitable heating habits such as combustion of wastes and inappropriate operation of the appliances. There were only small differences between single stoves and central heating boilers or between wood and coal-fired appliances. The emission factors calculated are higher than those cited in literature, which are mainly derived from trials on test stands under laboratory conditions.

Air Pollutants↗
PubMed2002

Omphalocele and gastrochisis.

Between January 1989 and November 1996 we detected a total of 44 cases of anterior abdominal wall defects comprising 29 with an omphalocele and 15 with gastrochisis. The gestational age at antenatal diagnosis of gastrochisis (mean = 17 weeks, 95% CI = 15-19) was significantly lower than for omphalocele (mean = 19.0 weeks, 95% CI = 17-21). Whereas gastrochisis tended to occur in relatively younger mothers (mean age = 23 years), omphalocele was associated with a comparatively advanced maternal age (mean age = 28 years). The sensitivity of ultrasound detection was the same for both malformations (omphalocele = 86.2%; gastrochisis = 86.7%). Additional structural anomalies were found in a higher proportion of those with an omphalocele compared with those with gastrochisis (62% vs. 20%). All the three cases of chromosomal anomalies were detected in omphalocele fetuses with an intracorporeal liver. Perinatal mortality was higher, albeit nonsignificantly, among fetuses with omphalocele.

Adult↗
PubMed2001

Prenatal diagnosis of translocation and a single pericentric inversion 9: the value of fetal ultrasound.

A total of 2741 high-risk pregnant mothers underwent invasive prenatal procedures, and in 94 of them (3.4%), fetal chromosomal or genetic anomalies were detected. In this study, we report on single pericentric inversions of chromosome 9 as well as translocations, which constituted 32% (30 of 94) and 16% (15 of 94) of all identified chromosomal or genetic abnormalities, respectively. In six fetuses of the 30 with an inversion of chromosome 9, ultrasound findings were abnormal and consisted of hydramnios, anhydramnios, hydroureter, hydronephrosis, encephalocele and prune belly syndrome, occurring singly or in combination. Among the 15 fetuses with chromosomal translocations, five had sonographic abnormalities. In conclusion, we found detailed ultrasound survey of fetuses with either translocations or inversions of chromosome 9 to be an additional source of useful information concerning fetal status that could be of value in genetic counselling of affected parents.

Journal Article↗
PubMed2000

Allegations of sexual abuse in child custody disputes.

OBJECTIVE: Allegations of sexual abuse are increasingly made in the context of divorce proceedings. The aim of the study was to describe ideal typical patterns of family dynamics when sexual abuse is alleged in divorce proceedings. METHOD: Development of an assessment plan according to the methods of the qualitative descriptive social sciences and retrospective assessment of 24 legal cases of custody and visitation right proceedings in which allegations of sexual abuse (N = 30 children) were made. RESULTS: In our sample, we found a significant incidence of sexual deviations of a parent. With respect to the allegations of sexual abuse in divorce cases, we were able to identify four types of family dynamics. Our qualitative assessment of the data showed that distinguishing between actual abuse and false allegations cannot adequately help to clarify the family dynamics. Rather, it tends to conceal the fact that even a false allegation usually originates from a sexualized atmosphere in the family. The main family structures which were observed without exception in our sample generally already existed before the separation phase and had corresponding effects on the child which must be considered in the evaluation.

Adolescent↗
PubMed1999

Omphalocele and gastroschisis: prenatal diagnosis and peripartal management. A case analysis of the years 1989-1997 at the Department of Obstetrics and Gynecology, University of Homburg/Saar.

OBJECTIVE: The article presents a retrospective analysis (1989-1997) of the prenatal diagnosis, the course and completion of pregnancy of 26 fetuses with omphalocele and 18 fetuses with gastroschisis. SUBJECTS: 44 pregnancies with anterior fetal wall defect diagnosed by prenatal ultrasound, clinical or patho-anatomic examination between 1989 and 1997 at the Department of Obstetrics and Gynecology, University of Homburg/Saar. RESULTS: In 40 of 44 pregnancies (91%) the fetal ventral abdominal wall defect could be detected antenatally with ultrasound. Associated malformations in fetuses with omphalocele were seen in 18 cases (69%), whereas only five fetuses with gastroschisis (28%) had an associated malformation. Nineteen of 26 fetuses (73%) with omphalocele had a normal karyotype. Seven of 26 fetuses (27%) with omphalocele had an abnormal karyotype. Eleven fetuses with omphalocele were live born, three of them with minor anomalies. Ten babies with omphalocele survived. No chromosomal anomalies were detected in fetuses with gastroschisis. There were four gastrointestinal malformations and one lethal associated malformation in fetuses with gastroschisis. There were 15 live born babies with gastroschisis, all of whom have survived. In 20 of 44 cases (45%) with ventral abdominal wall defect oligohydramnios could be detected by ultrasound. In 28 of 44 cases (64%) we found fetal growth retardation <10th percentile for gestational age. CONCLUSION: In case of a fetal ventral abdominal wall defect, the detection and appropriate classification of associated fetal anomalies is of great importance for the further course of pregnancy. Fetal karyotyping should be offered in case of a fetal abdominal wall defect. Early and close prenatal consultation of the neonatologist and the pediatric surgeon will favorably influence the perinatal outcome.

Adult↗
PubMed1997

A report on 158 cases of transcervical chorionic villus sampling.

Between 1989 and 1994 first trimester transcervical chorionic villus sampling was offered to 158 patients after proper counselling. The gestational age range was 9-12 weeks. The most important indication was advanced maternal age (75.4%). Adequate sampling after two, and a maximum of three attempts, was achieved in 98% and 99.3% of patients respectively. After the first year of the study karyotyping using the direct method alone was successful in 96% of cases. The success of karyotyping cultures was 98%. Excluding one false positive result the rate of fetal karyotypic abnormalities was 4.8%. 5 spontaneous abortions occurred (3.2%), all in patients of advanced maternal age. Moderate or severe vaginal bleeding occurred in 6.7% of the patients. There was no case of chorioamnionitis.

Abortion, Spontaneous↗
PubMed1997

Antenatally detectable markers for the diagnosis of autosomally trisomic fetuses in at-risk pregnancies.

Our aim was to investigate the contribution of certain antenatally detectable markers leading to the diagnosis of trisomic fetuses we observed over a period of 6 years. In our study, we specifically analyzed the role played by advanced maternal age and sonographically discovered abnormalities in the detection of autosomal trisomies. All together, 27 fetuses had this disorder, representing 28.7% (27 of 94) of all cytogenetic aberrations detected at our center over the same period. Down syndrome (12 cases) and Edward syndrome (11 cases) were the most common trisomies, while 4 cases of Patau syndrome were also diagnosed. The most common indication leading to diagnosis was abnormal ultrasound finding (48.2%), followed by advanced maternal age (44.4%). However, 63% of the trisomic fetuses belonged to mothers aged 35 years and above. Down syndrome fetuses (41.7%) had prenatally detected sonographic anomalies, 63.6% for Edward syndrome, and all fetuses with Patau syndrome (4 of 4) showed abnormal sonographic signs. Trisomy 21 presented with the following features: hydramnios, complex malformations, pyelectasis, and duodenal atresia. Trisomy 18 fetuses showed hydramnios, intrauterine growth retardation, microcephaly, spina bifida, and nonimmune hydrops fetalis. Signs observed in fetuses with trisomy 13 were: hydrocephalus, intrauterine growth retardation, oligoanhydramnios, complex malformations, severe fetal bradycardia and hydronephrosis.

Adult↗
PubMed1994

[PgE2 gel and PgE2 vaginal tablets for induced labor--a prospective randomized study].

In a prospective randomised study, the effects of an intracervical gel containing 0.5 mg PgE2 and an intravaginal tablet containing 3 mg PgE2 were compared in their efficiency to induce delivery at term. When only gel was used, induction failed in 45% of the cases, especially with an initially immature cervix score. However, these patients did show significant improvement of the Bishop score. The vaginal tablet was more effective with regard to the induction of delivery. When using the vaginal tablet alone, induction failed in only 5% of cases (p < 0.001). Best results, however, were obtained with a combination of both application forms. In this group there were no failures. Tablet application induced delivery within 24 hours in 56% of the cases, gel application in only 27% (p < 0.001). There were no significant differences observed in these groups during the course of labour. The length of the latency period was identical, whether a tablet or a gel was used in initiating labour. In 29% of the cases, beta-sympathicomimetics had to be used because of tetanic contractions or polysystolia. No significant differences in the occurrence of these contractions were seen in either the gel or the tablet group. Even in a high-risk collective with 25% pathological Doppler-flow findings, no higher rate of operative deliveries or fetal acidoses was observed after prostaglandin induction, if careful surveillance of the patients and early use of tocolytics in experienced hands were administered. Our results further confirm the concept of a differential induction of labour with prostaglandins.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Intravaginal↗
PubMed1994

Child-welfare recommendations in contested divorce and separation cases. Critical family situations and problematical behavior patterns on the part of parents and children.

Out of a collection of 121 child and adolescent psychiatric or psychological recommendations in family court cases, some 60 opinions were subjected to retrospective study. All the cases studied involved a single child to be recommended. In a retrospective analysis, the aim was to identify dangerous psychological constellations in the separating families, in particular typical behavioral and coping patterns of the parents in the process of separation and the typical reactive patterns of the children caught in the process. The study is designed as a descriptive analysis with the aim of sensitizing the helping-systems involved to better perception of such problem constellations. Thus it offers recommendations for parents, lawyers, judges and social-workers in the separation process.

Adaptation, Psychological↗
PubMed1994

[Significance of "abnormal reaction susceptibility" of adolescents in Munchausen by proxy syndrome. Simulation, folie à deux, induced artefact disease or what else?].

There are very few publications about the induction of emotional disturbances in Munchausen by proxy syndrome, although we see these children in our clinical work. While the pathology of the inducing mothers has been described quite well, the equally important question of pathological reactions of the child, which is a major factor at least in adolescents, has not yet been discussed. We present an unusual case of induced borderline psychosis and discuss the above mentioned aspect in relation to several psychopathological concepts, particularly Erikson's identity diffusion and folie à deux. We conclude that the concept of a simple induction of the disturbance in adolescents, which has been used so far, is insufficient. According to the authors the importance of the reactions discussed in this paper reaches far beyond Munchausen by proxy syndrome. The same reactions can for example be seen also in cases of sexual abuse. A bigger sample of patients needs to be investigated to confirm our considerations.

Adolescent↗
PubMed1993

Voltage- and transmitter-gated currents of all-amacrine cells in a slice preparation of the rat retina.

All-amacrine cells are crucial interneurons in the rod pathway of the mammalian retina. They receive input synapses from rod bipolar cells and make electrical output synapses into the ON-pathway and glycinergic chemical synapses into the OFF-pathway. Whole-cell currents from more than 50 voltage-clamped All-amacrine cells were recorded in a slice preparation of the rat retina. The recorded cells were identified by intracellular staining with Lucifer yellow. Spike-like potentials could be elicited upon depolarization by current injection. A voltage-activated, fast, TTX-sensitive, inward Na+ current was identified. A prominent outward K+ current could be suppressed by tetraethylammonium. GABA as well as glycine activated Cl- channels, which could be blocked by bicuculline and strychnine, respectively. Four agonists of excitatory amino acid receptors--kainate (KA), AMPA, 2-amino-4-phosphonobutyrate (APB), and NMDA--were tested. Inward currents at holding potentials of VH = -70 mV were found by application of KA and AMPA but not by application of APB and NMDA. These currents could be blocked by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX). ACh did not evoke any current responses.

4-Aminopyridine↗
PubMed1991

[Discolored amniotic fluid--results of prenatal diagnosis and clinical significance].

7000 pregnancies were analysed after genetic amniocentesis in respect of the further course and results of prenatal diagnosis (observation period 1975-1988). In 3.1% (217 cases) samples of amniotic fluid were discoloured. Vaginal haemorrhages prior to amniocentesis were recorded with significantly higher incidence (18%) in patients with discoloured amniotic fluid than in a control group (n = 217) with normal colour of the amniotic fluid (4.6%) (p less than 0.001). Miscarriages and chromosome anomalies occurred more often in the study group (3.7%/2.8%, control group: 0.9%/1.8%, n.s.). The risk of miscarriages was increased in cases with sanguineous amniotic fluid if the amniotic fluid alpha-fetoprotein values were enhanced at the same time. Significant differences were observed in respect of the incidence of foetal malformations in patients with discoloured amniotic fluid (7.8%) and in the control group (2.3%) (p less than 0.01). Borderline or definitely pathological amniotic fluid AFP concentrations were found often if the amniotic fluid was discoloured (6.9%, control group 3.2%). If discoloured amniotic fluid was sampled, foetal malformations should be excluded sonographically. In 82% of all cases with discoloured amniotic fluid and foetal malformations pathological sonographic findings and/or enhanced MS-AFP values were recorded even prior to amniocentesis.

Amniocentesis↗
PubMed1991

[Comparison of perineal sonography and abdominal ultrasound examination in placenta praevia].

This study describes a comparison between two different ultrasound methods used to localize a low-lying placenta or a placenta previa. The methods implemented were the abdominal ultrasound and the so-called "perineal scan", an ultrasound examination of the female urogenital tract, which is performed by using the perineum as an acoustic window. Between 1985 and 1988, 84 patients, suspected of having a low-lying placenta, were examined by perineal scanning. In all these cases it was possible to compare the results with those of abdominal ultrasound examinations documented in the patient's records. The "perineal scan"-examinations were performed "blind", i.e., without knowledge of the results of prior abdominal ultrasound. Abdominal sonography was performed by a different examiner using the full-bladder-technique. Perineal scanning was done a short time after voiding. The results showed considerable and significant (p less than 0.001) discrepancies between the two methods; perineal scanning more often demonstrated higher grade diagnoses (27 patients, 32%) than vice versa (9 patients, 11%). These differences may be at least partially explained by the influence of bladder distension. Probably a full bladder produces false negative results more often than previously suspected. An analysis of pregnancy outcome yielded positive predictive values of 78% (abdominal ultrasound) and 86% (perineal scanning). Perineal scanning therefore seems to provide an uncomplicated and reliable means to verify an abdominal placenta localisation.

Cesarean Section↗
PubMed1991

[Pathologic Doppler flow findings and cardiotocography results].

Of 1950 pregnant patients (2870 Doppler ultrasound measurements) we observed, in a study group with highly abnormal Doppler-flow findings (n = 66, Feb. 1990), a correlation of Doppler flow and FHR-recordings. Among these 66 patients we retained 60 (91%) in the hospital. They had at least 2 FHR-recordings a day. The results of Doppler flow measurements in the fetal aorta and umbilical artery correlated well with diagnosis of IUGR. The comparison of the overall results of both fetal vessels did not indicate any significant difference. In 21% of all patients with highly abnormal Doppler flow findings, was no abnormal FHR record until delivery. 26% already showed an abnormal non-stress test before the first pathological Doppler assessment, in 44% abnormal FHR-recordings were observed later than the first abnormal Doppler flow finding in the course of pregnancy. The median interval was 13.5 days in cases with increased Doppler flow parameters but with detectable end-diastolic blood flow and was reduced to 8 days in cases with absent end-diastolic blood flow. In 9% of all cases, abnormal results were found with both methods on the same day. In 32% we observed a reproducible notch in Doppler flow velocimetry of uteroplacental vessels. The rate of congenital malformations was 14%. Thus abnormal Doppler flow signals can be estimated as "early" prognostic criterias for a compromised fetus at risk.

Birth Weight↗
PubMed1991

[Doppler ultrasonography--perinatal data in cases with end-diastolic block and reverse flow].

In 50 cases with an end-diastolic zero flow or reverse flow all antenatal and perinatal abnormalities have been recorded. The fetal outcome was registered. The percentage of highly dystrophic newborns (percentile less than 5) was 88%. The perinatal mortality counted up to 16% and the percentage of congenital malformations (including chromosomal anomalies) was 12%. A reverse flow was registered in 4 cases. The perinatal mortality of those cases with reverse flow was 100%. In approx. one-quarter of those pregnancies and in 50% of the perinatally deceased newborns, there were no pathological or suspicious changes in the antepartal and/or subpartal CTG-recordings. The Duplex sonographical diagnosis of an end-diastolic zero flow/reverse flow, has a highly positive predictive value, whereas its sensitivity is low. It can be regarded as a very helpful parameter in clinical diagnosis, particularly as it is independent of borderline values. The correct choice of the high-pass wall filter (50-100 Hz) is important.

Adult↗
PubMed1990

Actions of excitatory amino acids on brisk ganglion cells in the cat retina.

1. Retinal ganglion cell activity was recorded extracellularly in the intact cat eye. We examined the effects of iontophoretically applied glutamate (GLU), aspartate (ASP), and the specific agonists kainate (KA), quisqualate (QQ), (RS)-alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA), and N-methyl-D-aspartate (NMDA) on the spontaneous and light-driven activity of ganglion cells. 2. ASP and GLU increased the spontaneous as well as the light-driven activity of all brisk cell types. The effects of the two drugs were very similar. The activity of most cells remained at a constant increased level during prolonged application of these drugs. 3. KA also excited all brisk ganglion cell classes and caused effects very similar to those of GLU and ASP but was effective at a much lower concentration. In general, brisk ganglion cells responded most vigorously to KA application. 4. QQ excited approximately 50% of all ON-X and OFF-X cells encountered, the other 50% of the X cells and all Y cells were inhibited during QQ-application. This inhibition was quite likely due to the stimulation of glycinergic and GABAergic interneurons, because it was reduced or abolished during application of the respective antagonists strychnine and bicuculline. All ganglion cells apparently received either direct or indirect excitatory input from QQ receptors, which can be revealed by blocking the inhibitory interneurons. 5. The major actions of QQ on the discharge rate of ganglion cells are mimicked by AMPA. Hence, the actions of QQ are likely to be mediated by the "classical" QQ-receptor, ion-channel complex rather than by the recently described type of QQ-receptor that is coupled to a second messenger system. 6. NMDA excited ON-X, OFF-X, and OFF-Y cells but inhibited ON-Y cells. Excitatory and inhibitory NMDA effects could be blocked by the specific NMDA-receptor antagonists D(-)-2-amino-7-phosphono-heptanoate (AP-7) or 3-((+/-)-2-carboxypiperazin-4-yl)propyl-1-phosphonic acid (CPP). If the GABAergic transmission was blocked by bicuculline, the NMDA-induced inhibition of ON-Y cells was abolished. We conclude that NMDA activates GABAergic interneurons that in turn reduce the activity of ON-Y cells.

Amino Acids↗
PubMed1989

[Nedocromil sodium therapy in asthma patients. Therapeutic effect in addition to treatment with oral theophylline and inhaled bronchodilator agents].

131 asthmatics aged 12-65 years, who still had symptoms despite inhaled or oral bronchodilators, were included in this double-blind group comparative study involving nedocromil sodium (2 puffs of 2 mg each twice daily) and placebo (2 puffs twice daily). The study was carried out at 8 centers over six weeks. Under nedocromil sodium, cough, dyspnea and severity of attacks were reduced significantly. Overall patient assessment also clearly favoured the active substance. Nedocromil sodium was also superior to placebo in terms of the improvement of lung function (FEV1, FVC and PEFR). 26 patients complained of unusual symptoms (12 under nedocromil sodium, 14 under placebo). Nedocromil sodium proved to be an effective, safe and well-tolerated drug in the antiinflammatory long-term treatment of reversible obstructive airways disease.

Administration, Inhalation↗