Terminally substituted conjugated polyenes : synthesis and energy transfer properties

The present publication summarizes the results of our investigations on conjugated polyenes with different end groups. The spectroscopic data reveal the possibi~ity of a selective electronic end group excitation in the conjugated systems influenced by steric factors between the end groups and polyene chains. An intramolecular energy transfer from one excited terminal substituent to the other via the polyene chain is likely. The interruption of the conjugation in the polyenes by a bicycloalkane unit results in a separation of the molecules' spectroscopic behavior. Energy transfer is modified, but still present

Terminally substituted conjugated polyenes : synthesis and energy transfer properties

The present publication summarizes the results of our investigations on conjugated polyenes with different end groups. The spectroscopic data reveal the possibi~ity of a selective electronic end group excitation in the conjugated systems influenced by steric factors between the end groups and polyene chains. An intramolecular energy transfer from one excited terminal substituent to the other via the polyene chain is likely. The interruption of the conjugation in the polyenes by a bicycloalkane unit results in a separation of the molecules' spectroscopic behavior. Energy transfer is modified, but still present

Do differences in diagnostic criteria for late fetal growth restriction matter?

BACKGROUND: Criteria for diagnosis of fetal growth restriction differ widely according to national and international guidelines, and further heterogeneity arises from the use of different biometric and Doppler reference charts, making the diagnosis of fetal growth restriction highly variable. OBJECTIVE: This study aimed to compare fetal growth restriction definitions between Delphi consensus and Society for Maternal-Fetal Medicine definitions, using different standards/charts for fetal biometry and different reference ranges for Doppler velocimetry parameters. STUDY DESIGN: From the TRUFFLE 2 feasibility study (856 women with singleton pregnancy at 32+0 to 36+6 weeks of gestation and at risk of fetal growth restriction), we selected 564 women with available mid-pregnancy biometry. For the comparison, we used standards/charts for estimated fetal weight and abdominal circumference from Hadlock, INTERGROWTH-21st, and GROW and Chitty. Percentiles for umbilical artery pulsatility index and its ratios with middle cerebral artery pulsatility index were calculated using Arduini and Ebbing reference charts. Sensitivity and specificity for low birthweight and adverse perinatal outcome were evaluated. RESULTS: Different combinations of definitions and reference charts identified substantially different proportions of fetuses within our population as having fetal growth restriction, varying from 38% (with Delphi consensus definition, INTERGROWTH-21st biometric standards, and Arduini Doppler reference ranges) to 93% (with Society for Maternal-Fetal Medicine definition and Hadlock biometric standards). None of the different combinations tested appeared effective, with relative risk for birthweight &lt;10th percentile between 1.4 and 2.1. Birthweight &lt;10th percentile was observed most frequently when selection was made with the GROW/Chitty charts, slightly less with the Hadlock standard, and least frequently with the INTERGROWTH-21st standard. Using the Ebbing Doppler reference ranges resulted in a far higher proportion identified as having fetal growth restriction compared with the Arduini Doppler reference ranges, whereas Delphi consensus definition with Ebbing Doppler reference ranges produced similar results to those of the Society for Maternal-Fetal Medicine definition. Application of Delphi consensus definition with Arduini Doppler reference ranges was significantly associated with adverse perinatal outcome, with any biometric standards/charts. The Society for Maternal-Fetal Medicine definition could not accurately detect adverse perinatal outcome irrespective of estimated fetal weight standard/chart used. CONCLUSION: Different combinations of fetal growth restriction definitions, biometry standards/charts, and Doppler reference ranges identify different proportions of fetuses with fetal growth restriction. The difference in adverse perinatal outcome may be modest, but can have a significant impact in terms of rate of intervention.</p

Zum Gedenken an Otto Graf, universeller Bauforscher in Stuttgart. Abschiedsvorlesung von Prof. Dr.-Ing. H. W. Reinhardt

Inhalt: Reinhardt, H.-W.: Otto Graf, Rückschau im Licht von heute (Abschiedsvorlesung am 4. Juli 2006), S. 7 - 41; Gehlen, Christoph: Rede des Direktors der Materialprüfungsanstalt Universität Stuttgart (MPA-Stuttgart / Otto-Graf-Institut (FMPA)) zur Verabschiedung von Herrn Prof. Dr.-Ing. H.-W. Reinhardt am 4. Juli 2006, S. 43 - 55; Thielen, Gerd: Kurze Ansprache des stv. Sprechers des Deutschen Ausschusses für Stahlbeton (DAfStb), S. 57 - 59; Eligehausen, Rolf: Ansprache des stv. Geschäftsführenden Institutsdirektors, S. 61 - 67; Fritsch, Dieter: Grußwort des Rektors der Universität Stuttgart aus Anlass der Abschiedsvorlesung von Herrn Prof. Dr.-Ing. Hans-Wolf Reinhardt, S. 69 - 75; Lebenslauf Hans-Wolf Reinhardt, S. 76; Lebenslauf Otto Graf, S. 77; Aus der Presse, S. 78; Die Autoren, S. 7

Reduced fetal growth velocity and weight loss are associated with adverse perinatal outcome in fetuses at risk of growth restriction.

BACKGROUND Although fetal size is associated with adverse perinatal outcome, the relationship between fetal growth velocity and adverse perinatal outcome is unclear. OBJECTIVE This study aimed to evaluate the relationship between fetal growth velocity and signs of cerebral blood flow redistribution, and their association with birthweight and adverse perinatal outcome. STUDY DESIGN This study was a secondary analysis of the TRUFFLE-2 multicenter observational prospective feasibility study of fetuses at risk of fetal growth restriction between 32+0 and 36+6 weeks of gestation (n=856), evaluated by ultrasound biometry and umbilical and middle cerebral artery Doppler. Individual fetal growth velocity was calculated from the difference of birthweight and estimated fetal weight at 3, 2, and 1 week before delivery, and by linear regression of all available estimated fetal weight measurements. Fetal estimated weight and birthweight were expressed as absolute value and as multiple of the median for statistical calculation. The coefficients of the individual linear regression of estimated fetal weight measurements (growth velocity; g/wk) were plotted against the last umbilical-cerebral ratio with subclassification for perinatal outcome. The association of these measurements with adverse perinatal outcome was assessed. The adverse perinatal outcome was a composite of abnormal condition at birth or major neonatal morbidity. RESULTS Adverse perinatal outcome was more frequent among fetuses whose antenatal growth was <100 g/wk, irrespective of signs of cerebral blood flow redistribution. Infants with birthweight <0.65 multiple of the median were enrolled earlier, had the lowest fetal growth velocity, higher umbilical-cerebral ratio, and were more likely to have adverse perinatal outcome. A decreasing fetal growth velocity was observed in 163 (19%) women in whom the estimated fetal weight multiple of the median regression coefficient was <-0.025, and who had higher umbilical-cerebral ratio values and more frequent adverse perinatal outcome; 67 (41%; 8% of total group) of these women had negative growth velocity. Estimated fetal weight and umbilical-cerebral ratio at admission and fetal growth velocity combined by logistic regression had a higher association with adverse perinatal outcome than any of those parameters separately (relative risk, 3.3; 95% confidence interval, 2.3-4.8). CONCLUSION In fetuses at risk of late preterm fetal growth restriction, reduced growth velocity is associated with an increased risk of adverse perinatal outcome, irrespective of signs of cerebral blood flow redistribution. Some fetuses showed negative growth velocity, suggesting catabolic metabolism

The mechanism of intramolecular energy transfer in terminally substituted polyene molecules

Absorption, fluorescence and excitation spectra of different terminally substituted polyenes have been recorded in the UV-Vis region. The observed intramolecular unidirectional energy transfer from a donor substituent to an acceptor at the other end of the chain is influenced but not inhibited by incorporation of a spacer into the polyene chain. In molecules without a spacer, internal conversion within the supermolecule can explain the observed transfer of energy. In molecules with a spacer interrupting the polyene chain the observed intramolecular energy transfer can be explained in terms of Förster transfer

Reward System Dysfunction as a Neural Substrate of Symptom Expression Across the General Population and Patients With Schizophrenia

Dysfunctional patterns of activation in brain reward networks have been suggested as a core element in the pathophysiology of schizophrenia. However, it remains unclear whether this dysfunction is specific to schizophrenia or can be continuously observed across persons with different levels of nonclinical and clinical symptom expression. Therefore, we sought to investigate whether the pattern of reward system dysfunction is consistent with a dimensional or categorical model of psychosis-like symptom expression. 23 patients with schizophrenia and 37 healthy control participants with varying levels of psychosis-like symptoms, separated into 3 groups of low, medium, and high symptom expression underwent event-related functional magnetic resonance imaging while performing a Cued Reinforcement Reaction Time task. We observed lower activation in the ventral striatum during the expectation of high vs no reward to be associated with higher symptom expression across all participants. No significant difference between patients with schizophrenia and healthy participants with high symptom expression was found. However, connectivity between the ventral striatum and the medial orbitofrontal cortex was specifically reduced in patients with schizophrenia. Dysfunctional local activation of the ventral striatum depends less on diagnostic category than on the degree of symptom expression, therefore showing a pattern consistent with a psychosis continuum. In contrast, aberrant connectivity in the reward system is specific to patients with schizophrenia, thereby supporting a categorical view. Thus, the results of the present study provide evidence for both continuous and discontinuous neural substrates of symptom expression across patients with schizophrenia and the general populatio