How can patient registries facilitate guideline-based healthcare? A retrospective analysis of the CEDATA-GPGE registry for pediatric inflammatory bowel disease.

BACKGROUND: Early diagnosis is mandatory for the medical care of children and adolescents with pediatric-onset inflammatory bowel disease (PIBD). International guidelines ('Porto criteria') of the European Society for Pediatric Gastroenterology, Hepatology and Nutrition recommend medical diagnostic procedures in PIBD. Since 2004, German and Austrian pediatric gastroenterologists document diagnostic and treatment data in the patient registry CEDATA-GPGE on a voluntary basis. The aim of this retrospective study was to analyze whether the registry CEDATA-GPGE reflects the Porto criteria and to what extent diagnostic measures of PIBD according to the Porto criteria are documented. METHODS: Data of CEDATA-GPGE were analyzed for the period January 2014 to December 2018. Variables representing the Porto criteria for initial diagnostic were identified and categorized. The average of the number of measures documented in each category was calculated for the diagnoses CD, UC, and IBD-U. Differences between the diagnoses were tested by Chi-square test. Data on possible differences between data documented in the registry and diagnostic procedures that were actually performed were obtained via a sample survey. RESULTS: There were 547 patients included in the analysis. The median age of patients with incident CD (n = 289) was 13.6 years (IQR: 11.2-15.2), of patients with UC (n = 212) 13.1 years (IQR: 10.4-14.8) and of patients with IBD-U (n = 46) 12.2 years (IQR: 8.6-14.7). The variables identified in the registry fully reflect the recommendations by the Porto criteria. Only the disease activity indices PUCAI and PCDAI were not directly provided by participants but calculated from obtained data. The category 'Case history' were documented for the largest part (78.0%), the category 'Imaging of the small bowel' were documented least frequently (39.1%). In patients with CD, the categories 'Imaging of the small bowel' (χ2 = 20.7, Cramer-V = 0.2, p < 0.001) and 'Puberty stage' (χ2 = 9.8, Cramer-V = 0.1, p < 0.05) were documented more often than in patients with UC and IBD-U. CONCLUSION: The registry fully reproduces the guideline's recommendations for the initial diagnosis of PIBD. The proportion of documented diagnostic examinations varied within the diagnostic categories and between the diagnoses. Despite technological innovations, time and personnel capacities at participating centers and study center are necessary to ensure reliable data entry and to enable researchers to derive important insights into guideline-based care.

Attosecond clocking of correlations between Bloch electrons.

Delocalized Bloch electrons and the low-energy correlations between them determine key optical1, electronic2 and entanglement3 functionalities of solids, all the way through to phase transitions4,5. To directly capture how many-body correlations affect the actual motion of Bloch electrons, subfemtosecond (1 fs = 10-15 s) temporal precision6-15 is desirable. Yet, probing with attosecond (1 as = 10-18 s) high-energy photons has not been energy-selective enough to resolve the relevant millielectronvolt-scale interactions of electrons1-5,16,17 near the Fermi energy. Here, we use multi-terahertz light fields to force electron-hole pairs in crystalline semiconductors onto closed trajectories, and clock the delay between separation and recollision with 300 as precision, corresponding to 0.7% of the driving field's oscillation period. We detect that strong Coulomb correlations emergent in atomically thin WSe2 shift the optimal timing of recollisions by up to 1.2 ± 0.3 fs compared to the bulk material. A quantitative analysis with quantum-dynamic many-body computations in a Wigner-function representation yields a direct and intuitive view on how the Coulomb interaction, non-classical aspects, the strength of the driving field and the valley polarization influence the dynamics. The resulting attosecond chronoscopy of delocalized electrons could revolutionize the understanding of unexpected phase transitions and emergent quantum-dynamic phenomena for future electronic, optoelectronic and quantum-information technologies.

Intersubband Polariton-Polariton Scattering in a Dispersive Microcavity.

The ultrafast scattering dynamics of intersubband polaritons in dispersive cavities embedding GaAs/AlGaAs quantum wells are studied directly within their band structure using a noncollinear pump-probe geometry with phase-stable midinfrared pulses. Selective excitation of the lower polariton at a frequency of ∼25 THz and at a finite in-plane momentum k_{‖} leads to the emergence of a narrowband maximum in the probe reflectivity at k_{‖}=0. A quantum mechanical model identifies the underlying microscopic process as stimulated coherent polariton-polariton scattering. These results mark an important milestone toward quantum control and bosonic lasing in custom-tailored polaritonic systems in the mid and far infrared.

Long-term pattern and magnitude of soil carbon feedback to the climate system in a warming world.

In a 26-year soil warming experiment in a mid-latitude hardwood forest, we documented changes in soil carbon cycling to investigate the potential consequences for the climate system. We found that soil warming results in a four-phase pattern of soil organic matter decay and carbon dioxide fluxes to the atmosphere, with phases of substantial soil carbon loss alternating with phases of no detectable loss. Several factors combine to affect the timing, magnitude, and thermal acclimation of soil carbon loss. These include depletion of microbially accessible carbon pools, reductions in microbial biomass, a shift in microbial carbon use efficiency, and changes in microbial community composition. Our results support projections of a long-term, self-reinforcing carbon feedback from mid-latitude forests to the climate system as the world warms.

Real-time observation of interfering crystal electrons in high-harmonic generation.

Acceleration and collision of particles has been a key strategy for exploring the texture of matter. Strong light waves can control and recollide electronic wavepackets, generating high-harmonic radiation that encodes the structure and dynamics of atoms and molecules and lays the foundations of attosecond science. The recent discovery of high-harmonic generation in bulk solids combines the idea of ultrafast acceleration with complex condensed matter systems, and provides hope for compact solid-state attosecond sources and electronics at optical frequencies. Yet the underlying quantum motion has not so far been observable in real time. Here we study high-harmonic generation in a bulk solid directly in the time domain, and reveal a new kind of strong-field excitation in the crystal. Unlike established atomic sources, our solid emits high-harmonic radiation as a sequence of subcycle bursts that coincide temporally with the field crests of one polarity of the driving terahertz waveform. We show that these features are characteristic of a non-perturbative quantum interference process that involves electrons from multiple valence bands. These results identify key mechanisms for future solid-state attosecond sources and next-generation light-wave electronics. The new quantum interference process justifies the hope for all-optical band-structure reconstruction and lays the foundation for possible quantum logic operations at optical clock rates.

A massive intestinal vaso-occlusive crisis or "girdle syndrome" in a 6-year-old boy observed as a first manifestation of sickle cell disease.

UNLABELLED: Sickle cell disease is a chronic hematologic disease with variable but often severe systemic symptoms. In this report, we describe a 6-year-old boy presenting with acute bowel pseudo-obstruction. During this episode, previously undiagnosed sickle cell disease was discovered upon peripheral blood smear analysis. The condition was therefore interpreted as a massive intestinal vaso-occlusive crisis or "girdle syndrome". Conservative treatment with hydration therapy, analgesia and a manual partial exchange transfusion was initiated. The patient fully recovered within 5 days. CONCLUSION: Girdle syndrome is a rare but severe adverse event associated with sickle cell disease that must be considered as differential diagnosis in patients with sickle cell disease.

[Solitary synchronous intraocular metastasis of a peripheral non-small cell lung cancer : A multidisciplinary approach with curative intention]. / Singuläre synchrone intraokulare Metastase eines peripheren Bronchialkarzinoms : Interdisziplinäres Therapiekonzept mit kurativer Intention.

A solitary synchronous distant metastasis of newly diagnosed non-small cell lung cancer (NSCLC) occurs in only a small number of patients. The available literature suggests a significant rise in long-term survival for these patients when resection of the bronchial carcinoma and the metastasis are feasible and performed. To demonstrate a multidisciplinary concept, we present the case of a patient with a peripheral NSCLC and a solitary synchronous intraocular metastasis. To our knowledge, this concept with curative intention has not been published before regarding a patient with an intraocular metastasis.

[Correlation between glaucomatous hemifield scotomas and measurements of nerve fiber layer thickness using scanning laser polarimetry]. / Korrelation zwischen glaukomatösen Halbfeldskotomen und Messungen der Nervenfaserschichtdicke mittels Scanning-Laser-Polarimetrie.

BACKGROUND: The purpose of the present study was to investigate wether a reduction of the retinal nerve fiber layer (RNFL) in patients with hemifield scotoma can be measured with scanning laser polarimetry and wether regional RNFL parameters can be correlated with the corresponding visual field indices. PATIENTS AND METHODS: We included one eye from each of 40 normal subjects and one eye from each of 40 glaucoma patients. Automated perimetry was performed and the RNFL was analyzed. RESULTS: HMD values obtained by white-white (W/W) and blue-yellow (B/Y) perimetry failed to correlate significantly with most of the corresponding RNFL parameters obtained with the GDx. Significant correlations were only shown for the inferior HMD (W/W and B/Y) and the superior ratio, superior average, and deviation superior. Furthermore, we found a high correlation between differences of upper and lower GDx parameters and differences of upper and lower visual field indices of W/W and B/Y perimetry. CONCLUSIONS: Scanning laser polarimetry can detect differences in RNFL sectors in patients with functional hemifield differences and carries the potential to detect changes in RNFL thickness at an early stage.

[Differential regulation of expression of PDGF receptors on corneal epithelial cells]. / Differenzielle Regulation der Expression von PDGF-Rezeptoren auf kornealen Epithelzellen.

BACKGROUND: The function of platelet-derived growth factor (PDGF) during corneal wound healing is only incompletely understood to date. Previous studies have shown that the mRNA of PDGF receptor type alpha (PDGFR alpha) and type beta (PDGFR beta) is expressed in cultured corneal epithelial cells (CEP). To add to the current knowledge, the following study was designed to compare the expression of mRNA and protein of both PDGF receptor subtypes in cultured CEPs and in CEPs ex vivo. METHODS: Total RNA and protein were extracted from cultured CEPs and from CEPs ex vivo according to standard protocols. The reverse-transcription polymerase chain reaction (RT-PCR) was applied to detect specific expression of the mRNA of PDGFR alpha and PDGFRss. The expression of the corresponding proteins was detected using Western blotting. RESULTS: MRNA and protein of both PDGF receptor subtypes could be detected in cultured CEPs but not in CEPs ex vivo. CONCLUSION: The present study shows for the first time that mRNA and protein of both PDGF receptor subtypes are expressed in cultured human corneal epithelial cells, while corneal epithelial cells ex vivo do not express these receptors. The differential up-regulation of PDGF receptors in activated cells during wound healing could be of pathophysiological importance.

Evaluation of glaucomatous visual field loss with locally condensed grids using fundus-oriented perimetry (FOP).

PURPOSE: We compared detection rates of glaucomatous visual field defects (VFDs) between a conventional rectangular stimulus grid and locally condensed test point arrangements in morphologically suspicious regions. METHODS: Humphrey Field Analyzer model 630 (HFA I, program 30-2 with a rectangular 6 degrees x 6 degrees grid) was used as the conventional perimetric method. Individual local test-point condensation was realized by fundus-oriented perimetry (FOP) on the Tuebingen Computer Campimeter (TCC). RESULTS: Of a total of 66 glaucoma patients, or suspected sufferers, 23 showed normal findings and 27 showed pathological findings with both methods. In 15 cases we found normal visual fields in HFA 30-2, whereas FOP revealed early glaucomatous functional damage. Only one case showed pathological HFA results, while FOP was normal. Detection rates of VFDs significantly differed between the two methods (p < 0.001; sign test). CONCLUSIONS: FOP, using individually condensed test grids, significantly increases detection rates of glaucomatous VFDs in morphologically suspicuous areas compared with a conventional HFA 30-2 technique using equidistant rectangular (6 degrees x 6 degrees) test point arrangements.

Intensity dependence of cation kinetic energies from 2,5-dihydroxybenzoic acid near the infrared matrix-assisted laser desorption/ionization threshold.

The mechanisms responsible for matrix-assisted laser desorption/ionization (MALDI) are far from being well understood, particularly where infrared laser irradiation is used to initiate the process. We measured the emission yields and kinetic energy distributions of positive ions emitted from 2,5-dihydroxybenzoic acid loaded with angiotensin II in a standard MALDI preparation during irradiation with an infrared free-electron laser tuned to 2.94 microm. As the laser intensity is scanned through the MALDI threshold, we see a marked change in the energy distributions of the matrix ion. Above threshold, the energy distributions of both analyte and matrix cations are constant over a broad range of laser intensities. This behavior does not appear to be consistent with any extant model of the MALDI mechanism.

Clinical evaluation of twice-daily emedastine 0.05% eye drops (Emadine eye drops) versus levocabastine 0.05% eye drops in patients with allergic conjunctivitis.

PURPOSE: The efficacy and safety of emedastine 0.05% eye drops (Emadine; Alcon Laboratories, Inc, Fort Worth, Texas), a new H(1) antagonist, were studied in comparison to levocabastine 0.05% eye drops (Livostin; Janssen-Cilag N V, Berchem, Belgium) during a twice-daily treatment schedule for 6 weeks in adult and pediatric patients with seasonal allergic conjunctivitis. METHODS: In a prospective, multicenter, randomized, double-masked, parallel group study, 222 patients with allergic conjunctivitis were randomized (221 received treatment) to either emedastine or levocabastine, instilled twice daily for 6 weeks. Patient diaries were completed four times daily (before the morning and evening instillations, at noon, and in the afternoon), and clinical examinations were conducted at regular intervals. Primary efficacy variables of ocular redness and itching and secondary efficacy variables of chemosis, eyelid swelling, patient diary data, and physician's global assessment were analyzed. RESULTS: Both emedastine and levocabastine produced a statistically significant (P =.0001) reduction in itching and redness within 5 minutes of the first instillation. All signs and symptoms improved progressively over the 6-week treatment period. After 7 days of use, and throughout the remainder of the study, emedastine was statistically superior to levocabastine (P <.006) in preventing and alleviating the signs and symptoms (itching, redness, chemosis, and eyelid swelling) of allergic conjunctivitis. CONCLUSIONS: Emedastine 0.05% eye drops administered twice daily are more efficacious than levocabastine 0.05% eye drops in the prevention and treatment of the signs and symptoms of allergic conjunctivitis in adults and children of 4 years and above. Both emedastine 0.05% eye drops and levocabastine 0.05% eye drops were well tolerated.

[Are filtering interventions in glaucoma patients with extensive visual field defects associated with a higher functional risk?]. / Sind filtrierende Eingriffe bei Glaukompatienten mit ausgedehnten Gesichtsfeldausfällen mit einem grösseren funktionellen Risiko verbunden?

BACKGROUND: We evaluated the prevalence of the loss of visual acuity due to loss of the central portion of the visual field and foveolar fixation in the first week after glaucoma filtering surgery. PATIENTS AND METHODS: We included 408 patients, in whom glaucoma filtering surgery was performed between January 1993 and April 1997 at the University Eye Clinic in Tübingen and who had completed 1-year follow-up examinations. The retrospective evaluation included preoperative, intraoperative and postoperative data. We excluded all patients who did not complete 1-year follow-up examinations (12 +/- 3 months), who have died during the 1-year follow-up, who had combined glaucoma and cataract surgery or in whom the Molteno implant procedure was performed. RESULTS: A total of 404 patients (99.3%) did not suffer loss of the central visual field and foveolar fixation in the first week after glaucoma filtering surgery. In 11 cases, loss of visual acuity > 2 dB was due to progressive lens opacification. One patient suffered from postoperative progression of his age-related maculopathy. In one patient (0.2%) progression of a preexisting relative central scotoma occurred immediately after the operation. Two patients (0.5%) suffered from loss of fixation and the central visual field immediately after glaucoma filtering surgery. CONCLUSIONS: Loss of the central visual field and central fixation immediately after glaucoma filtering surgery is a rare complication. Therefore, glaucoma filtering surgery can also be recommended for patients with advanced visual field defects.

Effect of cytokines on regulation of the production of transforming growth factor beta-1 in cultured human Tenon's capsule fibroblasts.

PURPOSE: Transforming growth factor-beta1 (TGF-beta1) is thought to play a pivotal role in the regulation of the wound healing process after glaucoma filtering surgery. The aim of the present study was to investigate whether platelet-derived growth factor isoforms (PDGF-AA, PDGF-BB), basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), interleukin-1beta (IL-1beta) and transforming growth factor-beta1 (TGF-beta1) modulate the production of latent and/or active TGF-beta1 by cultured human Tenon's capsule fibroblasts (HTF). METHODS: Human Tenon's capsule fibroblasts were seeded at two different densities (30 cells/mm2 and 150 cells/mm2) and stimulated for five days with PDGF-AA, PDGF-BB, bFGF, EGF, IL-1beta and TGF-beta1. Control cells were treated with serum-free medium (WM/F12). The concentrations of latent and active TGF-beta1 in the medium were determined using an immunoassay before and after activation of TGF-beta1 by transient acidification. RESULTS: The concentration of latent TGF-beta1 in conditioned media from HTF seeded at high density (150 cells/mm2) significantly increased after stimulation with 5 ng/ml TGF-beta1 (151.5 +/-41.7 pg/ml) or 10 ng/ml IL-1beta (45.7+/-8.1 pg/ml). The concentration of active TGF-beta1 in conditioned media also significantly increased after stimulation of HTF with 5 ng/ml TGF-beta1 (48.4+/-27.5 pg/ml). CONCLUSIONS: The present results indicate that TGF-beta1 is the most potent inducer of its own synthesis in HTF. Activation of an autocrine TGF-beta1 loop may play a role in the wound healing response after glaucoma filtering surgery.

Nasal, pulmonary and autoinhaled nitric oxide at rest and during moderate exercise.

OBJECTIVE: To investigate nasal nitric oxide (NO) excretion, pulmonary NO excretion, and autoinhalation of nasally released NO at rest compared with that during moderate exercise in smokers and non-smokers. DESIGN: Prospective observational study. SETTING: University laboratory. PARTICIPANTS: Fourteen healthy adult volunteers. INTERVENTIONS: Breathing of NO-purified air supplied via a tube system at rest and during a bicycle-ergometer workload of 60 Watt over a time of 10 min. MEASUREMENT AND RESULTS: We examined nasal and pulmonary NO excretion in smoking (n = 7) and non-smoking (n = 7) adult human volunteers. At rest, we measured constant nasal NO excretion rates of 311 +/- 89 nl/min for non-smokers and 261 +/- 142 nl/min for smokers (mean +/- SD, n.s.). During 60 W exercise, nasal NO release remained unchanged, while pulmonary NO excretion doubled compared with the rates at rest (non-smokers: 40 +/- 21 nl/min versus 23 +/- 14 nl/min, p < 0.05; smokers: 41 +/- 8 nl/min versus 22 +/- 8 nl/min, p < 0.05). The differences between smokers and non-smokers in nasal or pulmonary NO excretion were not significant. To determine the autoinhaled amount of nasally released NO, we also measured the NO concentration within the nasopharynx of five volunteers during nasal breathing. The average inhaled NO concentration was 17.8 +/- 3.1 ppb at rest and this decreased to 9.3 +/- 1.8 ppb during exercise of 60 W, while minute ventilation approximately doubled from 9 +/- 2 to 21 +/- 3 l/min. CONCLUSION: Our results demonstrate that moderate exercise increased exclusively pulmonary NO excretion. Nasal NO release, which is 10 times higher at rest, was not changed. The decrease in autoinhaled NO concentration during exercise results from dilution of the continuous nasal release by the increased respiratory gas flow. The individual NO release allows no conclusion about smoking habits.

Cytokine regulation of hyaluronate production by human Tenon's capsule fibroblasts.

PURPOSE: The high-molecular weight glycosaminoglycan hyaluronate (HA), a component of the extracellular matrix, has been shown to play important roles in many biological processes including cell proliferation, migration and differentiation. In the present study, the effect of cytokines on production of hyaluronate (HA) by human tenon's capsule fibroblasts (HTF) was determined. METHODS: HTF (2(nd) passage) were seeded at a cell density of 30 cells/mm(2) and stimulated by six different cytokines (platelet-derived growth factor (PDGF)-AA, PDGF-BB, basic fibroblast growth factor (bFGF), epidermal growth factor (EGF), interleukin (IL)-1beta and transforming growth factor (TGF)-beta1). Controls were treated with aliquots of serum-free medium only. Concentrations of HA were determined using a radiometric assay based on the specific binding of HA to HA binding proteins. RESULTS: The concentration of HA in conditioned medium of HTF was significantly increased only after stimulation with PDGF-AA [10 and 100ng/ml], IL-1beta [1 and 10ng/ml] and TGF-beta1 [5ng/ml]. CONCLUSIONS: Production of HA by HTF is regulated by PDGF-AA, IL-1beta and TGF-beta1 and is speculated to be involved in the wound healing reaction after glaucoma filtration surgery.

Selection and reversion of azamethipos-resistance in a field population of the housefly Musca domestica (Diptera: Muscidae), and the underlying biochemical mechanisms.

The organophosphorus insecticide, azamethiphos, is widely used throughout the world to control the housefly, Musca domestica (L.). Since its commercial introduction to Denmark in 1983 for this purpose, we have monitored the toxicity of azamethiphos to housefly populations at livestock farms throughout the country and carried out regular field studies. The findings of our field studies, which have revealed a strong potential for resistance development, have been born out by regular surveys showing that resistance has increased in recent years. Through the analysis of a field derived laboratory strain, we have implicated oxidative and hydrolytic mechanisms together with altered acetylcholinesterase in this resistance. Our field and laboratory studies have also indicated that resistance is relatively unstable, and can revert in the absence of selection. The implications of our findings for the continued efficacy of azamethiphos are discussed.

[Does public access to defibrillators have a chance in Germany?--On the US model, legal considerations and justification]. / Hat die Public Access Defibrillation in Deutschland eine Chance?--Uber das US-Modell, rechtliche Bedenken und deren Berechtigung.

PURPOSE: The introduction of public access to defibrillation via automated external defibrillators makes it possible to reduce the incidence of sudden cardiac arrest cases. Since they may expect civil and criminal liability after negligence causing damage, many German potential First Responders might hesitate to use an AED. METHODS: After we demonstrate the medical reasons and compare the legal situation of Public Access Defibrillation between the USA and Germany we analyse a possible hesitation of German First Responders. RESULTS: More than 30 states of the USA provide immunity from civil liability after a public access defibrillation followed by damage due to negligence. However, only an AED-trained US-First Responder is granted immunity from civil liability. In Germany there is no immunity from civil and criminal liability in case of public access defibrillation with damage caused by negligence. CONCLUSION: German law will not decrease any possible hesitation by First Responders. For a successful system of public access defibrillation, revision of the legal situation is mandatory.

Novel metal-to-metal silyl-migration reactions in heterometallic complexes.

An unprecedented, intramolecular metal-to-metal silyl ligand migration reaction has been discovered in a series of phosphido-bridged iron-platinum complexes and which may be triggered by an external nucleophile. Thus, reaction of solutions of [(OC)3-(R1/3Si)Fe(mu-PR2R3)Pt(1,5-COD) (1a R1 = OMe, R2 = 3 = Ph; 1b R1 = OMe, R2 = R3 = Cy; 1c R1 = Ph, R2 = R3 = Ph; 1d R1 = Ph, R2 = R3 = Cy; 1e R1 = Ph, R1 = H, R3 = Ph) in CH2Cl2 with CO rapidly afforded the corresponding complexes [(OC)4Fe(mu-PR2R3)Pt(SiR1/3)-(CO)] (2a-e) in which the silyl ligand has migrated from Fe to Pt, while two CO ligands have been ligated, one on each metal. When 1a or 1c was slowly treated with two equivalents of tBuNC at low temperature, quantitative displacement of the COD ligand was accompagnied by silyl migration from Fe to Pt and coordination of an isonitrile ligand to Fe and to Pt to give [(OC)3-(tBuNC)Fe(mu-PPh2)Pt[Si(OMe)3](CNtBu)] (3a) and [(OC)3(tBuNC)-Fe(mu-PPh2)Pt[SiPh3](CNtBu)] (3c). Reaction of 2a with one equivalent of tBuNC selectively led to substitution of the Pt-bound CO to give [(OC)4-Fe(mu-PCy2)Pt[Si(OMe)3](CNtBu)] (4b), which reacted with a second equivalent of tBuNC to give [(OC)4Fe(mu-PCy2)-Pt[Si(OMe)3](CNtBu)2] (5b) in which the metal-metal bond has been cleaved. Opening of the Fe-Pt bond was also observed upon reaction of 3a with tBuNC to give [(OC)3(tBuNC)-Fe(mu-PPh2)Pt[Si(OMe)3](CNtBu)2] (6). The silyl ligand migrates from Fe, in which it is trans to mu-PR2R3 in all the metal-metal-bonded complexes, to a position cis to the phosphido bridge on Pt. However, in 5a,b and 6 with no metal-metal bond, the Pt-bound silyl ligand is trans to the phosphido bridge. The intramolecular nature of the silyl migration, which may be formally viewed as a redox reaction, was established by a cross-over experiment consisting of the reaction of 1a and 1d with CO; this yielded exclusively 2a and 2d. The course of the silyl-migration reaction was found to depend a) on the steric properties of the -SiR1/3 ligand, and for a given mu-PR2R3 bridge (R2 = R3 = Ph), the migration rate decreases in the sequence Si(OMe)3> SiMe2Ph> SiMePh2>>SiPh3; b) on the phosphido bridge and for a given silyl ligand (R1 = OMe), the migration rate decreases in the order mu-PPh2 >> mu-PHCy; c) on the external nucleophile since reaction of 1c with two equivalents of P(OMe)3, P(OPh)3 or Ph2PCH2C(O)Ph led solely to displacement of the COD ligand with formation of 11a-c, respectively, whereas reaction with two equivalents of tBuNC gave the product of silyl migration 3c. Reaction of [(OC)3-[(MeO)3Si]Fe(mu-PPh2)Pt(PPh3)2] (7a) with tBuNC (even in slight excess) occurred stereoselectively with replacement of the PPh3 ligand trans to mu-PPh2, whereas reaction with CO led first to [(OC)3((MeO)3Si)Fe(mu-PPh2)Pt(CO)-(PPh3)] (8a), which then isomerized to the migration product [(OC)4Fe(mu-PPh2)Pt[Si(OMe)3](PPh3)] (9a). Most complexes were characterized by elemental analysis, IR and 1H, 31P, 13C, and 29Si NMR spectroscopy, and in five cases by X-ray diffraction.

[Effect of lymphocyte-conditioned medium on expression of smooth muscle alpha-actin in lens epithelium cells in situ]. / Einfluss eines Lymphozytenkonditionierten Mediums auf die Expression des glattmuskulären alpha-Aktins in Linsenepithelzellen in situ.

PURPOSE: Contraction of the capsule of the ocular lens is based upon proliferation and contraction of transformed lens epithelial cells. It is assumed that these processes can be assisted by postoperative intraocular inflammation. Previously, we reported that lens epithelial cell proliferation is enhanced by lymphocyte-conditioned medium (LCM). In this study we investigated the effect of LCM as well as of a culture medium conditioned by pigmented ciliary epitheilal cells (CBCM) on the expression of the smooth-muscle alpha-actin of the contractile cytoskeletal elements. METHODS: Explants of the anterior lens capsule of freshly enucleated bovine eyes were cultured in serum-free LCM and CBCM for 3 days, followed by fixation. Smooth-muscle alpha-actin was identified by indirect immunoflorescence. Explants cultured in serum-free bFGF-containing and TGF-beta containing medium served as control. RESULTS: Lens epithelial cells expressed smooth-muscle alpha-actin under the influence of LCM or TGF-beta. No smooth muscle alpha-actin could be detected under the influence of CBCM or bFGF. CONCLUSION: Our results demonstrate that secreted molecules of activated lymphocytes are able to induce the transformation of lens epithelial cells into contractile myofibroblasts and may be involved in the post-operative contraction of lens capsules.