Luminescence, structural, and bonding trends upon varying the halogen in isostructural aurophilic dimers.

The preparation of three isonitrile complexes (p-tosyl)CH(2)NCAu(I)X (X = Cl, Br, and I) along with their structural, spectral, and computational characterization are reported. X-Ray crystallography reveals that these complexes all crystallize in the same space group, C2/c, and have closely related supramolecular structures. The three complexes exhibit crossed-dimer structures with short Au...Au aurophilic distances of 3.0634(4) A, 3.1044(7) A, and 3.1083(5) A, for X = Cl, Br, and I, respectively. These distances are among the shortest ligand-unassisted Au...Au interactions reported. While RNCAuX complexes that we reported earlier associate as anti-parallel, one-dimensional aurophilic polymers with long Au...Au distances (approximately 3.6 A) and exhibit orange-red phosphorescence, the analogous aurophilic dimers herein show seemingly counter-intuitive blue-green emissions despite having much shorter Au...Au distances. DFT computations are used to augment experiment and study the T(1) phosphorescent excited state of [RNCAuX](n) in parallel, anti-parallel, and staggered conformations. Excimeric bonding and large Stokes shifts are predicted for all models, the extent of which is sensitive to both "n" and conformation with trends commensurate with experimental luminescence data. Calculations for the three [MeNCAuX](2) dimeric complexes reveal blue-green phosphorescence with a red shift as a function of increasing halide softness, consistent with experimental data for (p-tosyl)CH(2)NCAu(I)X (Cl > Br > I). The overall experimental and theoretical work signifies the central role of ground-state aurophilic bonding and excited-state excimeric bonding on the electronic structure, hence facilitating development of structure-luminescence relations that may assist in the rational design of novel optoelectronic devices.

[Sickle cell anemia in perinatal placental diagnostics]. / Sichelzellenanämien in der perinatalen Plazentadiagnostik.

Hereditary hemoglobinopathies should be considered as differential diagnosis when examining placental specimens for fetal growth retardation and spontaneous abortion. They can cause various macroscopic and microscopic changes in the placenta that are relevant for routine pathology examination. The importance of interdisciplinary co-operation between obstetrics and pathology to achieve optimum diagnostics and therapy planning is demonstrated using the case of a pregnant woman with heterozygous genotype and her child with homozygous genotype. Within this context, the influence of hemoglobinopathies on placental pathology and fetal development are summarized and exemplified.

Metal effect on the supramolecular structure, photophysics, and acid-base character of trinuclear pyrazolato coinage metal complexes.

Varying the coinage metal in cyclic trinuclear pyrazolate complexes is found to significantly affect the solid-state packing, photophysics, and acid-base properties. The three isoleptic compounds used in this study are [[3,5-(CF3)2Pz]M]3 with M = Cu, Ag, and Au (i.e., Cu3, Ag3, and Au3, respectively). They form isomorphous crystals and exist as trimers featuring nine-membered M3N6 rings with linear two-coordinate metal sites. On the basis of the M-N distances, the covalent radii of two-coordinate Cu(I), Ag(I), and Au(I) were estimated as 1.11, 1.34, and 1.25 angstroms, respectively. The cyclic [[3,5-(CF3)2Pz]M]3 complexes pack as infinite chains of trimers with a greater number of pairwise intertrimer M...M interactions upon proceeding to heavier coinage metals. However, the intertrimer distances are conspicuously short in Ag3 (3.204 angstroms) versus Au3 (3.885 angstroms) or Cu3 (3.813 angstroms) despite the significantly larger covalent radius of Ag(I). Remarkable luminescence properties are found for the three M3 complexes, as manifested by the appearance of multiple unstructured phosphorescence bands whose colors and lifetimes change qualitatively upon varying the coinage metal and temperature. The multiple emissions are assigned to different phosphorescent excimeric states that exhibit enhanced M...M bonding relative to the ground state. The startling luminescence thermochromic changes in crystals of each compound are related to relaxation between the different phosphorescent excimers. The trend in the lowest energy phosphorescence band follows the relative triplet energy of the three M(I) atomic ions. DFT calculations indicate that [[3,5-(R)2Pz]M]3 trimers with R = H or Me are bases with the relative basicity order Ag << Cu < Au while fluorination (R = CF3) renders even the Au trimer acidic. These predictions were substantiated experimentally by the isolation of the first acid-base adduct, [[Au3]2:toluene]infinity, in which a trinuclear Au(I) complex acts as an acid.

[Comments on a report by the BQS on obstetric quality indicators]. / Stellungnahme zu einem Gutachten der BQS über geburtshilfliche Qualitätsindikatoren.

When re-evaluating an epidemiologically oriented BQS expertise concerning the quality indicators in obstetrics, we examined three essential methods in obstetrics to verify their scientific evidence and their clinical relevance. In doing so we ascertained that recording the fetal heart rate sub part, analysing fetal blood and determining the blood gas of the umbilical blood are entirely appropriate quality indicators during delivery from a clinical and medical point of view -- although to varying extents. Above all, these three indicators prove to be essentially better evidence-based than described in the BQS expertise. The search for an optimum of evidence-based data in medicine ends in certain fields such as, for example, in obstetrics there where no further randomized studies can be carried out for methodological or ethical reasons. This lack of evidence for the optimum grade I which can clearly be understood from an epidemiological point of view, however, should not lead to an evidence nihilism that fails to accept or admit existing evidence of the weaker grades II and III.

Competing reactions of secondary alcohols with sodium hypochlorite promoted by phase-transfer catalysis.

With aqueous hypochlorite and a phase transfer catalyst, secondary alcohols undergo hitherto unreported free radical reactions that compete with and effectively limit traditional ketone syntheses. Product mixture profiles are determined by reactant ratios, organic cosolvent, and availability of oxygen to the system. Under argon, over half of substrate alcohols, PhCH(OH)R, are converted to benzaldehyde and free radical products through beta-scission of intermediate alkyl hypochlorites. Secondary alcohols with R containing three or more carbons also may undergo delta chlorination.

[Diagnostic and therapy of a severe fetal parvovirus-B19-infection with persistence of viral DNA in the mothers blood but inconspicuous serological tests. Case report]. / Diagnostik und Therapie einer schweren fetalen Parvovirus-B19-Infektion bei mütterlicher Viruspersistenz, aber unauffälliger Serologie. Fallbericht.

In the 24th week of gestation we diagnosed a severe hydrops fetalis in a 25 year old VI gravid III para, who had contact to parvovirus B19 in the 14th week of gestation. Because of the severe anaemia of the fetus and the massively increased bilirubinoides in the amniotic fluid we decided at the same day to apply the first of four intrauterine transfusions. The serological patterns of maternal blood with highly positive parvovirus-B19-IgG and negative IgM suggested that an infection had occurred. Parvoviral DNA was found in maternal and fetal blood confirming the diagnosis of an acute intrauterine parvovirus-B19 infection. No viral DNA was detected in fetal ascites. IgM in fetal blood was negative. By means of four transfusions, the pregnancy could be prolonged until the 32 + 5th week of gestation while the ascites was declining. When rupture of membranes occurred, a cesarean section had to be performed due to contractions and presentation of the feet. The newborn's blood count exhibited a thrombocytopenia with normal haemoglobin and haematocrit. Five days after delivery, a blood exchange had to be done because of a hyperbilirubinaemia. After seven weeks, the child could be dismissed from hospital in good general status, with decreasing ascites, normal liver function and normal neurological status. The blood of the newborn was tested to be positive for IgG, while IgM-antibodies and parvovirus-B19-DNA were negative. The diagnosis of a parvovirus-B19 infection of a fetus with severe hydrops and anaemia could be verified by a positive proof for DNA in maternal blood, with negative IgM and highly positive parvovirus-B19-IgG and on the other hand highly positive viral DNA in fetal blood and in the amniotic fluid. 10 weeks after contact to parvovirus B19, i. e. in the 24th week of gestation, positive IgG- and negative IgM-antibodies were found in the mother's blood, whereas fetal complications were noticed. These data demonstrate that following an acute parvovirus-B19-infection of the mother IgM-antibodies can be proofed for 6 - 8 (- 10) weeks. On the other side parvovirus-B19-DNA in the mothers blood is detectable by means of PCR for 8 - 10 weeks and in some cases even more than 15 weeks.

[Emergency cervix cerclage in amniotic sac prolapse--a realistic option for prolonging pregnancy]. / Notfallmässiger Muttermundverschluss bei Fruchtblasenprolaps--eine realistische Option zur Schwangerschaftsverlängerung.

BACKGROUND: We tried to evaluate, whether emergency operative closure of the cervix (EOCC) is a realistic option for prolongation of pregnancy in cases with early opening of the cervix and prolapse of the amniotic sac (PAS) into the vagina. PATIENTS AND METHODS: We report on 16 patients with PAS between 15 + 3 and 28 + 1 weeks of gestation and cervix dilatation between 2 and 8 cm. After antibiotic and tocolytic treatment we performed EOCC in 7 cases and EOCC + Cerclage in 9 cases. Pregnancy follow up and fetal outcome were analysed retrospectively. RESULTS: Mean gestational age at delivery was 33 + 1 weeks (9 cases > 32 + 0 weeks, 2 cases between 28 + 0 and 31 + 6 weeks, 3 cases between 25 + 0 and 27 + 6 weeks, 1 case with rupture of membranes during operation and immediate cesarean section at 28 + 1 weeks, 1 miscarriage at 23 + 3 weeks). Time between EOCC and delivery was between 0 and 146 days (mean 56.3 days), 14 fetuses survived healthy. The best results were obtained after EOCC + cerclage. CONCLUSION: If antibiotic and tocolytic treatment was successful in stopping local infection and contractions, EOCC is an acceptable and mostly successful procedure to prolong pregnancy.

[Uncomplicated obstetric injury as a risk factor for anal incontinence? Objective assessment of manometric measurements]. / Die unkomplizierte Geburtsverletzung als Risikofaktor analer Inkontinenz? Objektivierung durch manometrische Messungen.

The proximity of the anorectal sphincter apparatus and the vagina is a risk factor for faecal incontinence in women. To study the impact of the first delivery on anorectal continence, we evaluated 74 primiparae (41 women with midline episiotomy and 33 women with either intact perineum or Grade I tear only) and compared them to a control group of 18 nulliparous women. All subjects were examined by anorectal manometry and asked to complete a standardized questionnaire. Fourteen women of the primiparae group (eight patients with episiotomy, six pats. with intact perineum) had experienced incontinence of flatus, and 6 patients (8%, one pat. (3%) with intact perineum) had occasional incontinence of liquid or solid stool in the first weeks following delivery. We detected amongst those women who underwent episiotomy a significantly decreased maximum squeeze pressure and in women with an intact perineum a significantly decreased resting anal pressure. In all primiparae the anal canal length was significantly less when compared with control group. Even when the anal sphincter appears intact, the trauma of delivery causes detectable changes in the results of anorectal manometry, indicating a need for evaluation of the continence status at postpartum examination.

[Prenatal diagnosis and therapy of feto-fetal transfusion syndrome]. / Pränatale Diagnostik und Therapie des feto-fetalen Transfusionssyndroms.

Twin-twin transfusion syndrome (TTTS) is a serious complication of monochorionic twin pregnancies. It is the result of an unbalanced transfusion of blood across placental vascular anastomoses. TTTS appears predominantly in the second trimester of pregnancy characterized by discordance of growth as well as polyhydramnios in the recipient and oligo-/anhydramnios in the donor. Prenatal diagnosis is possible by non-invasive and invasive methods. The prognosis of the untreated TTTS is very poor. Serial amniocenteses and laser therapy are used resulting in survival rates of about 60%. Intrauterine death of one twin is associated with a high risk of morbidity in the surviving twin. Monochroionic twins have to be identified in early pregnancy. Close surveillance is necessary to diagnose TTTS at an early stage of the disease.