Real-time observation of multi-mode vibronic coherence in pentafluoropyridine.

The ultrafast dynamics of pentafluoropyridine in the 1 1B2 (ππ*) electronic state excited at λpump = 255 nm is investigated by femtosecond time-resolved time-of-flight mass spectrometry and photoelectron imaging spectroscopy. A pronounced, long-lived, and complex periodic modulation of the transient ion yield signal with contributions by four distinct frequency components, 72 cm-1, 144 cm-1, 251 cm-1, and 281 cm-1, is observed for up to 9 ps. The recorded photoelectron images display a spectral band from the excited 1 1B2 (ππ*) state only in the oscillation maxima; the signal is strongly reduced in the oscillation minima. Supported by electronic structure calculations at the RI-SCS-CC2 and XMCQDPT2 levels of theory, the oscillating components of the signal are identified as frequencies of b1 symmetry coupling modes in a vibronic coherence of the 1 1B2 (ππ*) and 1 1A2 (πσ*) electronic states. The optical excitation initiates regular and periodic wavepacket motion along those out-of-plane modes. In the distorted molecular structure, the initially excited state acquires substantial πσ* character that modulates the transition dipole moment for ionization and results in the observed oscillations.

Note: Energy calibration of a femtosecond photoelectron imaging detector with correction for the ponderomotive shift of atomic ionization energies.

Femtosecond photoelectron imaging spectroscopy is a powerful technique for following state-resolved molecular transformations in complex coupled potential energy landscapes. To avoid unwanted nonlinear side-effects, the employed laser pulse energies are usually reduced to minimal values. However, the energy calibration of the photoelectron imaging detector is ideally performed using multi-photon above-threshold ionization of suitable atomic species, for which rather high laser intensities are required. In this work, we show that the calibration spectra of xenon obtained with high laser pulse energies cannot be directly used for the evaluation of molecular photoelectron spectra recorded using low-energy laser pulses. The reason is the intensity-dependent AC Stark shift of the atomic ionization energies to larger values, which in turn leads to a corresponding decrease of the photoelectron kinetic energies. We present a simple procedure to quantify this so-called ponderomotive shift and calculate the theoretically expected un-shifted photoelectron energies.

Long-lived coherence in pentafluorobenzene as a probe of ππ(*) - πσ(*) vibronic coupling.

The dynamics of pentafluorobenzene after femtosecond laser excitation to the optically bright ππ(*) first excited electronic state have been investigated by femtosecond time-resolved time-of-flight mass spectrometry and femtosecond time-resolved photoelectron imaging spectroscopy. The observed temporal profiles exhibit a bi-exponential decay behavior with a superimposed, long-lived, large-amplitude oscillation with a frequency of νosc = 78-74 cm(-1) and a damping time of τD = 5-2 ps. On the basis of electronic structure and quantum dynamics calculations, the oscillations have been shown to arise due to vibronic coupling between the optically bright ππ(*) state and the energetically close-lying optically dark πσ(*) state. The coupling leads to a pronounced double-well character of the lowest excited adiabatic potential energy surface along several out-of-plane modes of b1 symmetry. The optical electronic excitation initiates periodic wavepacket motion along these modes. In the out-of-plane distorted molecular configuration, the excited state acquires substantial πσ(*) character, thus modulating the ionization probability. The photoelectron spectra and the anisotropy of their angular distribution confirm the periodically changing electronic character. The ionizing probe laser pulse directly maps the coupled electron-nuclear motion into the observed signal oscillations.

Ultrafast α -CC bond cleavage of acetone upon excitation to 3p and 3d Rydberg states by femtosecond time-resolved photoelectron imaging.

The radiationless electronic relaxation and α -CC bond fission dynamics of jet-cooled acetone in the S1 (nπ*) state and in high-lying 3p and 3d Rydberg states have been investigated by femtosecond time-resolved mass spectrometry and photoelectron imaging. The S1 state was accessed by absorption of a UV pump photon at selected wavelengths between λ = 320 and 250 nm. The observed acetone mass signals and the S1 photoelectron band decayed on sub-picosecond time scales, consistent with a recently proposed ultrafast structural relaxation of the molecules in the S1 state away from the Franck-Condon probe window. No direct signatures could be observed by the experiments for CC dissociation on the S1 potential energy hypersurface in up to 1 ns. The observed acetyl mass signals at all pump wavelengths turned out to be associated with absorption by the molecules of one or more additional pump and/or probe photons. In particular, absorption of a second UV pump photon by the S1 (nπ*) state was found to populate a series of high-lying states belonging to the n = 3 Rydberg manifold. The respective transitions are favored by much larger cross sections compared to the S1 ← S0 transition. The characteristic energies revealed by the photoelectron images allowed for assignments to the 3p and 3dyz states. At two-photon excitation energies higher than 8.1 eV, an ultrafast reaction pathway for breaking the α -CC bond in 50-90 fs via the 3dyz Rydberg state and the elusive ππ* state was observed, explaining the formation of acetyl radicals after femtosecond laser excitation of acetone at these wavelengths.

Impact of nuchal cord on measurement of fetal nuchal translucency thickness.

OBJECTIVE: To define the impact of nuchal cord on the measurement of fetal nuchal translucency thickness (NT). METHODS: Between December 2004 and June 2006, we examined prospectively 53 fetuses that were observed on routine first-trimester ultrasound examination between 11 + 3 and 13 + 6 weeks of gestation to have nuchal cord causing an indentation in the skin in the nuchal region. The fetuses were re-examined after a median interval of 132 min, when the cord was no longer around the neck and indentation of the skin had resolved. Various NT measurements (highest, lowest, mean) with the cord located around the neck (nuchal cord) were compared with NT measurements in the absence of nuchal cord ('true' NT) in the same fetuses. Measurements were considered to be equal when they were within mean +/- 1.96 SD, defined by our own intraobserver repeatability according to the method of Bland and Altman. RESULTS: The mean of the largest and the smallest of six measurements in the presence of nuchal cord fell within the mean +/- 1.96 SD of our own intraobserver repeatability, i.e. gave a correct estimate of the true NT, in 80% of fetuses, while the NT was overestimated in 10% and underestimated in 10% of fetuses. The largest and the smallest of six measurements in the presence of nuchal cord gave an underestimate of the true NT in 2% of fetuses and an overestimate in 4% of fetuses, respectively. CONCLUSION: There is a wide scattering of measurements in fetuses with nuchal cord in comparison to the same fetuses in the absence of nuchal cord. This prevents accurate prediction of the true NT, although the largest and smallest of repeat measurements with nuchal cord can allow calculation of the highest and lowest possible risks, respectively. These facts must be taken into consideration in counseling patients.

Ruptured false abdominal aortic aneurysm during pregnancy: Caesarean delivery followed by aortic reconstruction.

We describe a case of a successfully treated ruptured abdominal aortic aneurysm during pregnancy. The importance of close clinical follow-up after any aortic reconstructions is highlighted.

Fetal leptin and insulin levels only correlate inlarge-for-gestational age infants.

OBJECTIVE: To determine whether fetal leptin levels correlate with fetal weight and whether such correlation is direct or indirect via insulin or human placental lactogen (hPL), respectively. DESIGN: Cross-sectional study of offspring at term (n=175) with over-representation of large-for-gestational age (LGA; n=70) and small-for-gestational age (SGA; n=23) cases in a population of Caucasian women with no pregnancy pathology. METHODS: Fetal cord blood was collected after delivery. In several cases (n=62) paired mother-fetus blood samples were obtained. Leptin, insulin and hPL levels were measured by RIA. Anthropometric data (birth weight, body mass index, placental weight) were recorded. RESULTS AND CONCLUSIONS: Maternal insulin, hPL and leptin levels were higher than fetal concentrations. Cord blood leptin levels positively correlated with the anthropometric data with stronger correlations in female (0.54

Leptin receptor in human term placenta: in situ hybridization and immunohistochemical localization.

In the present study, we investigated the expression and localization of leptin receptors in human term placentae. On human term placenta tissue slices, digoxigenin-UTP labelled RNA-probe detected the long form of the leptin receptor ObR(L)mRNA in syncytiotrophoblasts of the villi, whereas the haematological subtype of the leptin receptor ObR/B219.1 was detected in blood cells of the intervillous space and fetal vessels. Immunohistochemistry, with two polyclonal antibodies to the N-terminus recognizing ObR(L)and ObR(S)of the leptin receptors and one to the C-terminus recognizing the long form of the leptin receptor ObR(L), localized leptin receptor protein at the apical membrane of the syncytiotrophoblasts. Our results show that the long form of the leptin receptor ObR(L)is expressed in human term placentae. We localized the long form of leptin receptor mRNA to the cytoplasm of syncytiotrophoblasts and leptin receptor proteins in human term placentae to the apical membrane of syncytiotrophoblasts. We conclude that in term placentae, leptin could mediate a growth promoting effect in the fetoplacental unit through the long form of the leptin receptor localized in the syncytiotrophoblasts. In contrast, the haematological subtype of the leptin receptor is not expressed in placental cells, but solely by blood cells in the intervillous space and fetal vessels.

[Leptin--an interim evaluation]. / Leptin--eine Zwischenbilanz.

The discovery of leptin, the product of the obese (ob)-gene, has broadened the horizons of research on energy balance. This hormone, produced and secreted by adipose tissue and some placental cells, finds its way to the hypothalamus, where it binds to the leptin receptors and signals satiety through the neuroendocrine axis. The fact that adipose tissue is not merely a storage depot, but also an important endocrine tissue, has revived the interest in the "lipostatic" theory of body fat regulation and has initiated many research efforts in the field of obesity, anorexia nervosa, bulimia, reproduction and haematology.

[Epidermal growth factor during pregnancy- a predictor of fetal growth retardation?]. / [Epidermaler Wachstumsfaktor im Schwangerschaftsverlauf - ein Prädiktor für fetale Wachstumsretardierung?]

Epidermal growth factor (EGF) in urine was measured at 4-week intervals in 83 women referred for suspected intrauterine growth retardation (IUGR); 138 women with normal singleton pregnancies and newborns of normal weight served as controls. Of the 83 women, 30 delivered babies with weight below the 10th percentile after week 37. During pregnancy these women had shown significantly lower EGF levels than women who delivered normal-weight babies. However, due to the wide distribution of individual EGF data, no clear clinical cut-off point between normal and IUGR values could be established.

Lipoprotein lipase, LDL receptors and apo-lipoproteins in human fetal membranes at term.

Ultrastructurally, all cells of human fetal membranes strongly exhibit a large amount of lipid deposits throughout pregnancy. Their origin and function is still unknown. The aim of this study was to investigate the localization of key components of lipid metabolism in this tissue. Using immunohistochemical techniques, the distribution of lipoprotein lipase (LPL), low density lipoprotein receptors (LDL receptors), and apo-lipoprotein B and E was investigated in 20 human fetal membranes at term. In addition, electron microscopy was used to study the intracellular localization of lipoprotein-sized particles. Amnionic epithelium and trophoblast cells reacted strongly for LPL. LDL receptors and apo-lipoproteins were present in amnionic epithelium and fibroblasts of the amnion. In none of the investigated cells were lipoprotein-sized particles identified. Similar results were obtained in all 20 cases. The findings indicate that lipoprotein from the amniotic fluid or from the maternal circulation may serve as substrate for lipids in human fetal membranes.

Successful treatment of primary extramedullary leukemia (EML) of the uterus with radical surgery, chemotherapy, autologous bone marrow transplantation (BMT) and prophylactic local irradiation.

Extramedullary myeloid cell tumors are rare manifestations of acute nonlymphocytic leukemia (ANLL). While many advances in diagnosis have been made, dilemmas remain concerning the treatment of this disease. In primary extramedullary leukemia (EML) most reports agree upon a local therapy followed by systemic chemotherapy such as is used for ANLL. However, further prophylactic local or systemic therapy with stem cell support remains controversial. A 20-year-old patient was diagnosed as having granulocytic sarcoma (GS) of the uterus without evidence of ANLL in 1991. After resection of the tumor at the uterine cervix and chemotherapy with daunorubicin 50 mg/m2 (days 1-3) and cytosine-arabinoside 200 mg/m2 (days 1-7) in September 1991, complete remission was achieved. In October 1991 cytosine-arabinoside 1000 mg/m2 every 12 h from day 1 to day 6 and amsacrine 200 mg from day 5 to day 7 were given as consolidation. Two years later relapse occurred in the adnexae. After radical hysterectomy, the same induction and consolidation chemotherapy was administrated. Subsequently, cytoxane 60 mg/m2 and fractionated total body irradiation (6 x 200 cGy) were given as conditioning and the previously cryopreserved bone marrow was reinfused. Finally, after hematopoietic engraftment, prophylactic local irradiation (4500 cGy) to the pelvis was given resulting in a disease-free long-term survival of more than 36 months after relapse. Although this experience is confined to one patient, it may contribute to the design of prospective therapeutic studies in patients with primary EML.

[Value of the TAG-72 (CA 72-4) tumor marker in primary diagnosis of ovarian carcinoma. A comparison with the established CA-125 marker]. / Stellenwert des Tumormarkers TAG-72 (CA 72-4) bei der Primärdiagnostik des Ovarialkarzinoms. Ein Vergleich mit dem etablierten Marker CA-125.

The value of the TAG-72 (CA 72-4) serum marker in primary diagnosis was investigated in 110 patients with histologically diagnosed ovarian cancer. A reference group consisted of 103 patients with benign pelvic masses. Compared to the well-established CA-125, TAG-72 showed a low sensitivity of 42% in the detection of ovarian cancer. By contrast, when the cut-off level for TAG-72 was set at 6 U/ml, it showed a very high specificity of 99%. When the measurement of TAG-72 was combined to that of CA-125, improvements in both the specificity (as compared to a single CA-125 determination) and the sensitivity (as compared to a single TAG-72 assay) were observed. In such a combined assay, our results suggest that the best predictive value (positive and negative) was obtained if CA-125 is assigned a relatively high cut-off value (65 U/ml) in conjunction with a low cut-off level (3.2 U/ml or 4 U/ml) for TAG-72. In the present study, at threshold values of 65 U/ml respectively, a sensitivity of 86%, a specificity of 83% and a positive and negative predictive value of 85% were obtained. In mucinous carcinomas of the ovary, however, the additional TAG-72 determination did not lead to a better predictive power than did CA-125 measurement alone.

[Adenofibroma and adenosarcoma of the uterus in young women]. / Adenofibrom und Adenosarkom des Uterus bei jungen Frauen.

We report on two similar cases of young women with irregular menstrual bleeding. Curettage and biopsy revealed an adenofibroma of the uterus in case 1 (31 yrs) and an uterine adenosarcoma in case 2 (30 yrs). Hysterectomy was subsequently performed in both patients: histological examination of the hysterectomy specimen showed no remnants of the tumour in case 1. There was adenosarcoma tissue in the uterine cavity of case 2 but no myometrial infiltration. The difficulties of differential diagnosis of uterine soft tissue tumours in young women are discussed and the literature is reviewed.

[Intrauterine pregnancy after conservative treatment of ectopic pregnancy with contralateral removal of the adnexa]. / Intrauterine Schwangerschaft nach konservierender Behandlung einer ektopischen Schwangerschaft mit kontralateraler Adnexentfernung.

Laparoscopic injection has become an important tool in tubal pregnancy. Intratubal injection of 5 mg of prostaglandin F2 alpha (PG F2 alpha) was successful at a serum human chorionic gonadotropin (hCG) level of more than 2500 mlU/ml. Intrauterine pregnancy occurred 112 days after laparoscopic treatment, during earlier removal of the contralateral tube.

Denial of pregnancy: obstetrical aspects.

Between 1987 and 1990 27 women were observed who professed they did not know they were pregnant until term or until premature contractions set in. The aim of this study was to evaluate obstetric history and pregnancy outcomes and assess defence mechanisms and coping strategies which contribute to negation of pregnancy. In 11 women pregnancy was denied until delivery, five of these had breech presentations. In nine women denial ended between 27 and 36 weeks and in seven women between 21 and 26 weeks of gestation. Three of the four fetal deaths that occurred and two of the three cases of prematurity occurred in the last group. There was no infanticide but one woman delivered her infant alone and concealed. Most women reported irregular, sometimes menstruation-like bleedings during pregnancy, three women had taken oral contraceptives during pregnancy. Few women reported actual symptoms of pregnancy, such as nausea and weight gain. Denial of pregnancy is a heterogeneous condition with different meanings and different psychiatric diagnoses in different women. Stressors (e.g. separation from partner, interpersonal problems etc.) do play an important role as precipitating factors for the development of an adjustment disorder with maladaptive denial of pregnancy. There is a fluid transition between conscious coping strategies and unconscious defence mechanisms.

Identification of CD34+ cord blood cells and their subpopulations in preterm and term neonates using three-color flow cytometry.

Three-color flow cytometry was used to identify CD34+ cord blood (CB) hematopoietic progenitors of preterm (n = 13) and term (n = 18) neonates. The frequency of CD34+ CB cells gated on the lymphocyte fraction in term neonates is about half the frequency of preterm neonates (mean 1.84 +/- 0.8 vs. 3.49 +/- 1.8, p < 0.005). The difference of absolute CD34+ cells between the 2 groups did not reach statistical significance (premature 169 +/- 161 vs. mature 108 +/- 62.6 x 10(6) cells/l). The proportion of myeloid lineage-committed CD34+ cells coexpressing the CD33 antigen in preterm neonates does not significantly differ from that found in term neonates. However, in preterm neonates a higher fraction of erythroid lineage-committed CD34+ cells coexpresses the CD71 antigen as compared with term neonates (mean 28.7 +/- 14.1 vs. 11.4 +/- 5.7, p < 0.001). The positive correlation between gestational age and the ratio of myeloid/erythroid lineage-specific progenitor cells (r = 0.61, n = 31, p < 0.0005) suggests gestational changes in lineage commitment of CD34+ cells.

[Rescheduling genetic amniocentesis from the 16th to the 13th/14th week of pregnancy--report of experience]. / Die Vorverlegung der genetischen Amniozentese von der 16. in die 13./14. Schwangerschaftswoche--ein Erfahrungsbericht.

At the ob/gy department of the Innsbruck University routine, genetic amniocentesis has been offered from the 13/14 week of gestation since 1991. In 1991 44.5% of all amniocenteses were performed as early amniocentesis, it rose in 1992 to 61.5%, the rest being performed in the 16th week of gestation. In a total of 346 genetic amniocenteses, 8 pathological karyotypes were obtained (six trisomies, one 47 XXY, one marker chromosome), six from samples obtained at early amniocentesis and two obtained at the 16th week. Three weeks following the procedure, a spontaneous abortion rate of 0.87% occurred. Cultivation took 1-2 days longer with samples from early amniocentesis than with samples collected at the 16th week. In two cases the cultures failed and a repeat procedure had to be performed at the 16th week. With early amniocentesis performed at week 13/14 results are known of gestation. The long period of anxiety, which many women see as a serious disadvantage of amniocentesis is thus significantly reduced.

[Increased uterine activity through histamine]. / Steigerung der uterinen Aktivität durch Histamin.

The influence of histamine, a biogenic amine known for many years, on the contractility of uterine specimens, was investigated. A highly significant (p > 0,0001) increase of uterine activity after the application of histamine 10(-6) M was observed, caused by a similar increase of frequency, duration and amplitude of the contractions.