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K Vetter

Publications and source records attributed to K Vetter.

At least 19 recordsLinked to original sources

Breakdown of K selection in 178Hf.

Coulomb activation of the four quasiparticle Kpi=16+ 178Hf isomer (t1/2=31 y) has led to the measurement of a set of Elamda matrix elements coupling the isomer band to the ground band. The present data combined with earlier 178 Hf Coulomb excitation data have probed the components in the wave functions and revealed the onset and saturation of K mixing in low-K bands, whereas the mixing is negligible in the high-K bands. The implications can be applied to other quadrupole-deformed nuclei.

Journal Article↗

[Birthplace free-standing birth center -- perinatal data in comparison with clinic deliveries in Bavaria and Berlin].

QUESTION: The purpose of this investigation is to find any differences between important maternal and infantile perinatal data from a clinic and a birth center group. Is the perinatal and/or maternal mortality in the birth center group higher? What influence do different socioeconomic factors have on the clinic group? PATIENTS AND METHODS: We have carried out a retrospective comparison of the obstetric parameters from all birth center deliveries in the states Berlin and Bavaria for the years 1999 and 2000 (n = 3,060) and the perinatal data investigations of selected clinical groups of both states (n = 55,875). RESULTS: Objective parameters in both groups regarding week of potation at delivery, parity, age of pregnant women, infantile measures, primi- and multiparae and Apgar scales were comparable. There are significant differences in the delivery mode (spontaneous deliveries: birth centers > clinics; operative deliveries: birth centers < clinics), in blood loss over 1,000 ml (birth centers > clinics), in the episiotomy and perineal tear rate (birth centers < clinics), in the infantile transfer rate to a neonatology unit (birth centers < clinics) and in the frequency of necessary neonatological measures in the neonate (birth centers > clinics). The perinatal and maternal mortality in the groups were similar. Within the clinical group the socioeconomic status and a background of immigration had no significant influence on the perinatal data. CONCLUSION: The retrospective data show that the more "invasive" clinical obstetrics leads to a similar postnatal condition of the neonates in comparison to the birth house group. Further comparative studies over several years are necessary to make statements about the occurrence of rare risks and maternal mortality in the free-standing birth center groups.

Adult↗

[Extraclinical obstetrics in the GDR? Medicohistorical notes].

In 1946 the share of clinic deliveries in the Soviet occupation zone amounted to 27 %, 1970 the given share of clinic deliveries in the GDR come to 99 %. From the beginning of the seventies home deliveries were not listed any more in the official statistics. After that neither the home obstetrics nor the family orientated clinical obstetrics took a larger space in the scientific discussions in the specialist public of the GDR. The following will show the development of the extraclinical obstetrics on the territory of the GDR as well as describe and discuss its medical and social context from the end of the forties until 1989. Usually in the (critical) reflections of the revival of home resp. extraclinical obstetrics in the eighties and nineties only the development in the "old" Federal Republic is taken into consideration. A description of the medicohistorical development in the former GDR in order to complete the all-German way of looking at this phenomenon was still due until now.

Delivery, Obstetric↗

Evidence for a new type of shears mechanism in 106Cd.

Lifetimes of states in the lowest lying positive parity band in 106Cd have been measured using the Doppler shift attenuation method. The deduced B(E2) transition rates show a marked decrease with increasing spin. Cranking and semiclassical model calculations suggest that the structure has the character of a shears-type band resulting from the coupling of g(9/2) proton holes to aligned pairs of h(11/2) and g(7/2) neutron particles. This is the first clear evidence for the phenomenon of "antimagnetic" rotation in nuclei.

Journal Article↗

Amniotic fluid insulin levels and fetal abdominal circumference at time of amniocentesis in pregnancies with diabetes.

AIMS: Fetal hyperinsulinism is a strong predictor for excessive growth and fetopathy in pregnancies complicated by diabetes. We examined (i). the relationship between measurements of amniotic fluid insulin (AF insulin) and fetal abdominal circumference (AC) at the time of amniocentesis, and (ii). whether there is a threshold for fetal AC percentiles which can identify low vs. high-risk levels of AF insulin without performing an amniocentesis. METHODS: In a retrospective study, AF insulin from 121 pregnant diabetic women (32 pregestational; 89 gestational) was measured during the 3rd trimester as part of a diabetes management protocol. AC measurements were transformed into a continuous variable of percentile growth for gestational age (Hadlock). Division of the cohort according to deciles or quartiles of AC percentiles was performed to identify a threshold AC with a significant increase in elevated AF insulin, previously defined as AF insulin >or= 7 microU/ml. A receiver operator characteristic (ROC) curve was created and the negative predictive value (NPV) of the determined threshold was calculated. RESULTS: AF insulin levels were significantly correlated with the AC percentiles (r = 0.3, P = 0.0005) by linear regression. No AC threshold could reliably identify a moderate elevated AF insulin >or= 7 microU/ml (NPV 77.2%), but an AC threshold >or= 75th percentile could identify with fetal hyperinsulinism with an AF insulin >or= 16 microU/ml. All 10 cases of AF insulin >or= 16 microU/ml were identified with a NPV of 100% (74/74). CONCLUSIONS: Our data indicate that an AC >or= 75th percentile determined by a 3rd trimester ultrasound examination may discriminate between pregnancies at low vs. high risk for AF insulin >or= 16 microU/ml. This AF insulin concentration corresponds to a level of hyperinsulinism reported to be associated with considerable neonatal and long term morbidity.

Adult↗

Coulomb excitation paths of high-K isomer bands in 178Hf.

Three distinctly different mechanisms are shown to populate the K(pi)=6(+) (t(1/2)=77 ns), 16(+) (31 yr), and 8(-) (4 s) isomer bands of 178Hf by Coulomb excitation. High spin states of the three isomer bands were populated by Coulomb excitation of a hafnium target with a 650 MeV 136Xe beam. Although direct population of high-K bands is highly K-forbidden, isomer bands in 178Hf were populated up to spins 13(+)(K=6), 20(+)(K=16), and 14(-)(K=8) with in-band gamma yields of approximately 10(-4) of the ground state band. The data are consistent with a rapid increase in K mixing with increasing spin in the isomer bands.

Journal Article↗

Rotational damping in ytterbium nuclei.

We have made the first clear measurements of rotational damping widths in nuclei. In a mixture of three Yb nuclei, these widths are 300 +/- 60 keV between 1.2 and 1.5 MeV gamma-ray energy [approximately (37-57)Planck's constant]. Compound damping and motional narrowing are discussed in connection with these results.

Journal Article↗

Effective charge of the (pi)h(11/2) orbital and the electric field gradient of Hg from the Yrast structure of 206Hg.

The gamma-ray decay of excited states of the two-proton hole nucleus, 206Hg, has been identified using Gammasphere and 208Pb+238U collisions. The yrast states found include a T(1/2) = 92(8) ns 10(+) isomer located above the known 5(-) isomer. The B(E2;10(+)-->8(+)) strength is used to derive the quadrupole polarization charge induced by the h(11/2) proton hole. Also, the implied quadrupole moment has been used to provide an absolute scale for the electric field gradient of Hg in Hg metal.

Journal Article↗

Very extended shapes in the A--110 region.

High-angular-momentum states in 108Cd were populated via the (64)Ni((48)Ca,4n) reaction at a beam energy of 207 MeV. Gamma rays were detected using the Gammasphere array. A rotational band has been observed with a dynamic moment of inertia and deduced lower limit of the quadrupole moment suggesting a major-to-minor axis ratio larger than 1.8:1, placing it among the most deformed structures identified in any nucleus, to date.

Journal Article↗

Expression of a novel mouse gene 'mbFZb' in distinct regions of the developing nervous system and the adult brain.

Using an induction gene trap approach with bFGF, we identified a novel mouse gene mbFZb (mouse basic FGF repressed, putative Zic binding protein). It shows high homology to a putative Zic3 binding protein in Xenopus (AF129131). We used the in situ hybridization technique on sections to analyze the expression pattern of mbFZb during embryonic development in the mouse. From E9.5 onwards it is expressed mainly in the developing nervous system, with high levels of expression in the proliferating neuroepithel of the brain and the neural tube, the ganglia of the cranial nerves V, VII, VIII, IX and X and the dorsal root ganglia. MbFZbtranscript can also be detected in the developing eye and the brown fat. In the adult brain strong expression is restricted to the olfactory bulb, the hippocampus, the piriform cortex and the Purkinje cells of the cerebellum. On the cellular level the mbFZb/GFP fusion protein is localized in vesicular structures in the cytoplasm.

Amino Acid Sequence↗

Pre-eclampsia associated alterations of the elastic fibre system in umbilical cord vessels.

Although pre-eclampsia (PE) is often associated with fetal hypoxia, hypertension and/or disturbed function of the fetal circulation, the effect of these altered hemodynamic parameters on the structure and composition of umbilical vessels has not been systematically investigated before. Therefore, this study focuses on PE-associated changes of the elastic fibre system in umbilical cord vessels investigated by light and electron microscopy, immunocytochemistry and biochemistry. In umbilical cord veins, no changes in thickness of the vessel wall or of any sublayer were observed. However, the internal elastic lamina of the veins was split in 80% of the PE-group in contrast to 20% in uncomplicated pregnancies. This effect was significant (alpha <0.01) from 36 weeks of gestation onwards. In umbilical cord arteries, the entire arterial vessel wall was found to be 15% thicker in PE than in uncomplicated pregnancies. The enlargement was caused by an increase of both the tunica intima and tunica media. The thickening of the tunica intima was attributed to a migration of smooth muscle cells towards the endothelium, accompanied by a splitting of the internal elastic lamina. Compared to uncomplicated pregnancies, smooth muscle cells of arteries and veins in PE showed a metabolic activation demonstrated by highly dilated endoplasmic reticulum. A semiquantitative score method as well as a quantitative dot blot assay indicated a PE-associated reduction of elastin expression in the arterial vessel walls. In summary, PE obviously induces a decrease of the elastin content accompanied by a thickening of the vessel wall in umbilical cord arteries. This remodeling of the elastic fibre system, together with an increased migration of smooth muscle cells, might represent part of the functional adaptation system of the umbilical cord arteries on the altered hemodynamic conditions in PE.

Adult↗

Increase of segments of elastic-type blood vessel walls in fetal placental stem villi during pre-eclampsia at term.

In recent studies we described the presence of elastic-type blood vessels within trunci and rami chorii of human placental stem villi. For systemic and pulmonary hypertension it is known that elastic fibres are enhanced in arteries. The aim of our study was, therefore, to examine whether pre-eclampsia may lead to an increase of elastic tissue fibres in blood vessel walls of placental stem villi and whether there are differences in the thickness of blood vessel walls within these villi when compared to normotensive pregnant women. Twenty-six women with uncomplicated pregnancies and 25 patients with pre-eclampsia were investigated. Unfixed cryostat serial sections were processed for conventional orcein staining and for the demonstration of alpha-actin-immunoreactivity. The intensity of orcein staining of stem villus blood vessel walls was evaluated by a semiquantitative score method. Significant higher intensities of orcein staining (P<0.00001) were calculated for blood vessel walls of placentae with pre-eclampsia. The amount of thick stem villus vessels (>41 microm) increased during pre-eclampsia from 39 gestational weeks onwards. Our study demonstrates that segments of thick blood vessel walls and elastic-type vessel walls are increased in placental stem villi of patients with pre-eclampsia. This reaction may protect the fetal placental vessels and avert an increase of the fetal hypertension.

Chorionic Villi↗

[Diabetes and pregnancy].

Preexisting type-I-diabetes (incidence 0.8%) and gestational diabetes (3-5%) are the two manifestations of disturbed carbohydrate metabolism in pregnancy. Maternal hyperglycemia and the resulting excessive glucose supply for the fetus leads to fetal hyperinsulinism which is responsible for the complications in the offspring. The most important clinical manifestations are the excessive growth of the fetus (macrosomia), the risk of intrauterine death and the neonatal morbidity caused by hypoglycemia and the delay of maturation of lungs and liver. Women with type-I-diabetes require preconception counseling and optimizing of glucose control to reduce the rate of abortion and of congenital anomalies of the offspring. Furthermore kidney function and retinopathia should be evaluated preconceptionally. The management of diabetic pregnancies requires a tight cooperation of obstetricians and diabetologists. Blood glucose levels have to be lower than outside pregnancy. Gestational diabetes is diagnosed by a screening test with 50 g glucose for all women followed by a regular 75 g oGTT when the glucose value is > or = 140 mg%. In most of the women euglycemia can be achieved by diet and exercise. Women after pregnancies with gestational diabetes should be retested postnatally and counseled about their increased risk to develop diabetes in later life.

Adult↗

Patients with preeclampsia develop agonistic autoantibodies against the angiotensin AT1 receptor.

Immune mechanisms and the renin-angiotensin system are implicated in preeclampsia. We investigated 25 preeclamptic patients and compared them with 12 normotensive pregnant women and 10 pregnant patients with essential hypertension. Antibodies were detected by the chronotropic responses to AT1 receptor-mediated stimulation of cultured neonatal rat cardiomyocytes coupled with receptor-specific antagonists. Immunoglobulin from all preeclamptic patients stimulated the AT1 receptor, whereas immunoglobulin from controls had no effect. The increased autoimmune activity decreased after delivery. Affinity-column purification and anti-human IgG and IgM antibody exposure implicated an IgG antibody directed at the AT1 receptor. Peptides corresponding to sites on the AT1 receptor's second extracellular loop abolished the stimulatory effect. Western blotting with purified patient IgG and a commercially obtained AT1 receptor antibody produced bands of identical molecular weight. Furthermore, confocal microscopy of vascular smooth muscle cells showed colocalization of purified patient IgG and AT1 receptor antibody. The protein kinase C (PKC) inhibitor calphostin C prevented the stimulatory effect. Our results suggest that preeclamptic patients develop stimulatory autoantibodies against the second extracellular AT1 receptor loop. The effect appears to be PKC-mediated. These novel autoantibodies may participate in the angiotensin II-induced vascular lesions in these patients.

Amino Acid Sequence↗

Is the liver of the fetus the 4th preferential organ for arterial blood supply besides brain, heart, and adrenal glands?

In this study we compared the distribution of blood flow to the liver in growth-retarded fetuses whose estimated weight was < 5th centile with normal-weight fetuses. As expected, the relative venous blood flow to the liver was reduced, with blood flowing preferentially through the ductus venosus. However, the total blood supply seemed to be maintained by a concomitant, significant increase in arterial blood flow through the hepatic artery. Absolute flow velocities such as the peak, minimum diastolic and temporal average velocities were changed, as was the flow waveform. Effectively, the deficiency in venous supply was made up for by an increase in arterial blood flow. This compensatory effect may be crucial for maintaining liver function in times of low portal venous blood supply. It thus makes sense to regard the liver as the fourth preferential organ for arterial blood supply in the compromised fetus, besides heart, brain, and adrenals.

Adrenal Glands↗