PDBe: Protein Data Bank in Europe.

The Protein Data Bank in Europe (PDBe; pdbe.org) is a partner in the Worldwide PDB organization (wwPDB; wwpdb.org) and as such actively involved in managing the single global archive of biomacromolecular structure data, the PDB. In addition, PDBe develops tools, services and resources to make structure-related data more accessible to the biomedical community. Here we describe recently developed, extended or improved services, including an animated structure-presentation widget (PDBportfolio), a widget to graphically display the coverage of any UniProt sequence in the PDB (UniPDB), chemistry- and taxonomy-based PDB-archive browsers (PDBeXplore), and a tool for interactive visualization of NMR structures, corresponding experimental data as well as validation and analysis results (Vivaldi).

Assignment and conformational investigation of asymmetric phenylindenylidene ruthenium complexes bearing N,O-bidentate ligands.

The NMR conformational study of three asymmetric phenylindenylidene ruthenium complexes 4.1-4.3, is presented. Complete (1)H and (13)C assignments could be obtained for 4.1-4.3 in benzene solution from multiple 2D homonuclear and heteronuclear NMR techniques. Our NMR analysis shows that each complex exists as a 55:45 mixture of two rotational isomers in slow exchange on the NMR chemical shift timescale. They are shown to be related by a 180 degrees flip of the indenylidene ligand along the Ru=CR bond. Both rotational isomers can be discriminated by means of NOEs contacts between the various ligands coordinating to the Ru. By matching these stereospecific assignments to the chemical shift, a chemical shift based fingerprint of the isomers that may allow straightforward assignment of future asymmetric phenylindenylidene ruthenium complexes is proposed.

Sn12O8(OH)4(OEt)28(HOEt)4: an additional member in the family of dodecameric oxo clusters.

A tin(IV) oxoalkoxo cluster with unprecedented architecture has been prepared and characterized by single-crystal X-ray diffraction. The cluster obeys the formula Sn 12O 8(OH) 4(OEt) 28(HOEt) 4 (1) and is based on an elongated centrosymmetric assembly of 12 six-coordinate tin centers, 28 peripheral ethoxy groups (terminal and bridging), 8 oxo bridges (mu2 and mu3), 4 hydroxy bridges (mu2), and 4 ethanol molecules that are all bound to tin atoms and interact strongly, through hydrogen bonds, with an ethoxy group located on a vicinal tin atom. This compound has also been fully characterized in solution by multinuclear 1D and 2D NMR, with all of its (119)Sn, (1)H, and (13)C NMR resonances assigned with respect to the structure. Altogether, the data allowed unambiguous location of the hydroxy groups. Information on the exchange of the ethoxy groups is also presented.

Acute type-A dissection of the aorta: which diagnostic modes remain for surgical indication?

The natural course of acute type-A dissection of the aorta (AADA) implies a mortality of 50% within the initial 2 days. Preoperative diagnostic tests have to be expeditious while avoiding hypertension and direct manipulation of the aneurysm to prevent aortic rupture. Since 1979, 51 patients have been operated upon for AADA. The diagnosis was established by one or more of the following methods: transthoracic echocardiography (TTE); transesophageal echocardiography (TEE); conventional angiography (CA); intravenous digital subtraction angiography (DSA); and computed tomography with bolus injection of contrast medium (CT). TTE (n = 26) showed a dissection in 72%, suggested an intimal flap in 25%, and missed the diagnosis in 1 case. CT (n = 15) and DSA (n = 10) failed to indicate dissection in 1 case each. CA (n = 27) demonstrated dissection in every case but was the most time-consuming and stressful method. Since the introduction of combined transthoracic and transesophageal echocardiography, no other diagnostic methods have been used. On the basis of this experience, we propose the following diagnostic plan: 1. in AADA, the demonstration of an intimal flap in the ascending aorta by TTE/TEE is an indication for immediate surgery without further diagnostic measures (10 patients: no false-positive findings); 2. if a dissection is suggested by TTE/TEE, then DSA is performed if the supra-aortic branches are suspected to be compromised; CT is preferred if an extrapericardial aortic rupture is suspected; 3. the time-consuming and stressful diagnostic approach of conventional angiography is no longer indicated.

Long-term survival after embolization of potentially lethal bleeding malignant pelvic tumours.

Transcatheter embolization was performed in 45 patients suffering from potentially lethal bleeding originating from malignant tumours in the pelvic region. In 21 cases, the basic disease was rectosigmoidal and in 20, gynaecological in origin. Uncommon bleeding sites were embolized in four other cases. The median survival time (Kaplan-Meier) was 6 months. Most patients died from tumour cachexia. In 10 cases (22%), recurrent bleeding occurred, in three of these with lethal consequences. Successful reembolization was performed on seven patients. The different embolization materials used showed a minor impact on the therapeutic result. Embolization therapy proved to be an effective measure in potentially lethal malignant pelvic bleeding. Gianturco, Anderson and Wallace (GAW) coils should be given preference where there is urgency, as they are accurate, easily and quickly insertable, and cause few complications.

Intravenous DSA and dynamic computed tomography for postoperative follow-up of type A aortic dissections.

We undertook a direct comparison of intravenous digital subtraction angiography and dynamic computed tomography in a follow-up study on 37 patients who had undergone surgery on the thoracic aorta for acute or chronic type A dissections. These are minimally invasive and complementary procedures: IV-DSA provides a clear angiographic image of the dissection, with visualization of the true and false channels, their distal extension and the supra-aortic and abdominal vessels they supply. Dynamic CT best demonstrates the proximal extension of the disease; it visualizes clotting in the false lumen and permits a more accurate measurement of the aortic width, and thus early recognition of a developing aneurysm.

[Computed tomographic detection of chemotherapy-induced thymus changes in patients with metastatic testicular tumors]. / Computertomographischer Nachweis chemotherapie-induzierter Thymusveränderungen bei Patienten mit metastasierten Hodentumoren.

Serial thoracic CT scans of 100 patients suffering from testicular cancer revealed that the thymus appears to atrophy temporarily during administration of cytostatic agents. About two months after cessation of chemotherapy rebound enlargement of the thymus occurs and persists for about two years followed by a slow involution. Using a semiquantitative score system, thymic CT images of these patients were compared with that of 100 patients suffering from other malignancies, 100 patients without malignant disease and 52 patients with myasthenia gravis, taking into account the age-related changes of the size of the organ. Rebound thymic enlargement should not be misinterpreted as metastatic lymph nodes.

[I.v. DSA in the diagnosis and follow-up of thoracic aortic dissection]. / I.v. DSA zur Diagnostik und Verlaufskontrolle der thorakalen Aortendissektion.

Intravenous DSA was performed in 53 patients with suspected dissection of the thoracic aorta and in 13 patients following surgery for aortic dissection. In 36 patients, the suspected diagnosis could be excluded definitely and, in 14 cases out of 17, a dissection was correctly diagnosed. All 11 type B dissections were correctly diagnosed. Of six type A dissections, only three were adequately demonstrated by IV DSA. In type B dissections, IV DSA is reliable, but in type A dissection with massive aortic insufficiency or pericardial tamponade the findings are not reliable. In all 13 patients who had surgery for dissection, IV DSA proved suitable for showing the anastomosis and progress of the disease.

[The diagnosis of lymphatic vascular dysplasia and lymphatic fistula formation]. / Zur Diagnostik von Lymphgefässdysplasie und Lymphfistelbildung.

The importance of lymphangiography for diagnosing the formation of lymphatic fistulas and vascular dysplasias of the lymphatic vessels is on the increase within the scope of therapeutic invasiveness. Its importance and ranking in diagnosing lymphatic circular disorders is demonstrated and exemplified by case reports on three patients suffering from chylothorax of various origin, on one patient with chyluria, and one patient with lymphoedema in the soft parts of the neck. In two chylothorax patients, lymphangiography resulted in successful surgery. It is the decisive method in diagnosis and therapy planning in fistulas and dysplasias of the lymphatic vessel system.

[Peripheral venous digital subtraction angiography in the follow-up of aortocoronary venous bypass grafts]. / Peripher venöse digitale Subtraktionsangiographie (DSA) zur Kontrolle von aortokoronaren Venenbypassgrafts (ACVB).

36 patients with 68 aorto-coronary venous bypass grafts (45 of which were angiographically patent) were examined via DSA (DV12V, serial mode, Philips) and angiography. Imaging was triggered via R waves, and effected in RAO 30 degrees, LAO 60 degrees, and AP projection. 63 of the 68 grafts were correctly detected (92.7%). Two anterior interventricular branch grafts (RIVA = ramus interventricularis anterior) were not visualised via DSA (95.6% sensitivity). One graft each to the RIVA, to the right coronary artery (RCA), and to the posterior branch of the lateral cutaneous branches of intercostal arteries (PLA), were falsely found to be patent (87% specificity). Grafts were visualised in full length. In some cases morphological changes of the walls were also visible.

[Digital subtraction angiography for the follow-up control of percutaneous transluminal angioplasty using a scoring system]. / Digitale Subtraktionsangiographie (DSA) zur Verlaufskontrolle der perkutan-transluminalen Angioplastie (PTA) unter Verwendung eines Scoresystems.

Seventy-two patients were examined by venous DSA following angioplasty, 28 of these within three weeks and 44 six months to three years after the procedure. The resolution of the DVI 2 V is adequate for showing reparative changes after dissection in the short-term follow-up. Demonstration was sufficient to enable one to use a coding system which classified the type and severity of the vascular changes. Clinical and angiographic follow-up showed good agreement regarding the amount of improvement obtained; in these patients, clinical follow-up alone is adequate. Where there has been no change in the clinical state or if there has been deterioration, a DSA examination should be carried out in order to ascertain the reason for the lack of improvement.

[Computer tomographic densitometry of primary liver tumors]. / Computertomographische Densitometrie primärer Lebertumoren.

The dynamic computed tomography (CT) densitometry is defined as the combination of rapid bolus injection of urographic contrast medium and timed sequential computed tomography scan permitting recognition of different patterns of enhancement. The results of this method on fifty patients with histologically proofed hepatic tumors (focal nodular hyperplasia n = 12, cavernous hemangioma n = 13, liver cell carcinoma in cirrhotic liver n = 10, primary liver cell carcinoma n = 6, bile duct carcinoma n = 4, others n = 5) are demonstrated. CT-densitometry offers valuable aid for the differential diagnosis of focal liver lesions, i.e. cavernous hemangioma, focal nodular hyperplasia of the liver.

[Experimental meniscus sonography: the influence of imaging geometry on the visualization of meniscal lesions]. / Experimentelle Meniskussonographie: Einfluss der Abbildungsgeometrie auf die Nachweisbarkeit von Meniskusläsionen.

Specific meniscal tears were set on prepared cadaver knees to examine the influence of projection factors on the visualisation of these lesions via ultrasound. 7.5 MHz sector- and linear scanner were used. It showed that both the extent of the lesion and also the angle between outgoing echo-direction and reflection plane determines the sonographic findings of meniscal tears. Adapted horizontal tears and vertical radial tears were often not seen. Concentric vertical lesions showed one or two high echogenic lines, depending on the extent of the defect. So it seems that there are limits for an exact sonographic characterization of meniscal lesions.

[Peripheral venous DSA of the calf arteries in arterial obstructive disease patients. A comparison with conventional angiography]. / Periphervenöse DSA der Unterschenkelarterien bei AVK-Patienten. Vergleich mit der konventionellen Angiographie.

The ability of venous DSA to demonstrate the calf vessels distal to the trifurcation in patients with proximal blocks was compared with conventional angiography in 33 patients (44 limbs) in a study carried out by four observers. In 11.1% cases, the vessels were demonstrated better by DSA and in 2.5% by conventional angiography. In 86.4% the quality was the same. The reasons for this are analysed.

[Suitability and comparison of compensating filters for thoracic diagnosis]. / Eignung und Vergleich von Ausgleichsfiltern für die Thoraxdiagnostik.

The effect of three types of filter on the quality of radiographs of the chest was compared. These filters improve visualization of mediastinal structures without significantly reducing the quality of the pulmonary image. In practice the Du Pont filter proved best; the quality of the central and peripheral portions of the lung image is equal to that of an ordinary radiograph and visualization of the mediastinum is improved. The Agfa-Gevaert filter showed no significant disadvantages compared with the ordinary techniques but the improvement in mediastinal visualization is not that marked. The 3 M filter yields poor images of the central portions of the lung and its type of construction prevents the retrocardiac structures from being pictured as well as with the other filters.

[Phantom studies using echo contrast media to improve the Doppler color sonographic imaging of the superficial femoral artery in the adductor canal]. / Phantomuntersuchungen mit echokontrastgebenden Substanzen zur Verbesserung der farb-doppler-sonographischen Darstellung der A. femoralis superficialis im Adduktorenkanal.

The adductor canal was simulated using 2.6 cm muscular tissue and 2 fasciae to analyse the limits of colour-coded Doppler sonography (angiodynography) in this region. Defects in the spectral signal cause a significant underestimation of mean, peak systolic and peak diastolic (backflow) velocities and of calculated blood flow. Furthermore the pulsatility index is overestimated and the colour-coded visualisation of the arteries is almost lost. For the most part, these changes can be compensated by administration of a sonographic contrast agent (SH U 454). A minimum of 9 mg microbubbles/ml blood is required. Nevertheless, the adjustment of system controls (e.g. transducer power) becomes more difficult and an ideal setting impossible.

[Postoperative conventional tomography of the temporal bone in the assessment of inadequate perception in patients with cochlear implants]. / Postoperative konventionelle Schläfenbeintomographie in der Beurteilung von reizinadäquaten Empfindungen (RIE) bei Cochlear-Implant-Patienten.

Between August 1984 and August 1990, 166 patients received a 22-channel cochlear implant (Nucleus) in the ENT clinic in Hannover. Some of these patients who were able to understand speech nevertheless complained of inadequate perception. To study this further a phantom skull with a cochlear implant was examined by CT and by conventional tomography of the petrous bone in various image planes. The method of choice for evaluating the position and appearance of the cochlear implant proved to be conventional tomography of the petrous bone in the frontal transorbital plane. In 7/23 patients examined it was possible to demonstrate dislocation of the electrodes; this is evidently responsible for the faulty perception.

[Arthritic changes in small and large joints in digital and conventional x-ray images]. / Arthritische Veränderungen an kleinen und grossen Gelenken im digitalen und konventionellen Röntgenbild.

In order to evaluate the suitability of digital radiography for the diagnosis of skeletal abnormalities, inflammatory joint changes were used to test this technique. Early erosive changes, fine irregularities and marginal lamellar abnormalities demand a high degree of resolution from the imaging method. 6 observers studied images of the hand of 67 and of the foot of 19 patients. Joint changes were staged according to the scheme proposed by Larsen; in this study the early stages predominated. With similar techniques there were no significant differences between the digital and conventional techniques. Images of 39 large joints (knee, shoulder, elbow, ankle) were compared only subjectively since even minor differences in projection were able to obscure some erosions. However, in this case also both techniques appear to be of similar value.

[Phantom studies of the value of color-coded Doppler sonography in arterial occlusive disease of the lower extremities]. / Phantomuntersuchungen zur Wertigkeit der farbkodierten Doppler-Sonographie bei der arteriellen Verschlusskrankheit der unteren Extremitäten.

A new practically orientated phantom for evaluating Doppler Duplex equipment was developed and used to determine the possibilities and limits of color coded Doppler Sonography (Angiodynography) in the diagnosis of arterial occlusive disease of the lower extremity. The problems that may occur in quantifying flow in these arteries are analyzed. The influence of superimposed slices of various soft-tissues on flow quantification, on the spectral waves and on color coded visualisation of the arteries and the possibility to compensate those changes by the use of sonographic contrast agents are discussed.

[Postoperative diagnosis following separate replacement of an aortic valve and an ascending aorta using IV-DSA and CT]. / Postoperative Diagnostik nach separatem Ersatz von Aortenklappe und Aorta ascendens mit IV-DSA und CT.

We performed a follow-up examination by intravenous DSA and dynamic CT of 14 patients with separate replacement of aortic valve and ascending aorta due to an aneurysm or an aortic dissection. In 5 patients, we found an aortic ectasia at the aortic bulb or a perfused "graft inclusion". Both are best demonstrated with dynamic CT. As a result of the study, the operation technique was changed. In the postoperative management of patients with separate replacement of aortic bulb and ascending aorta, careful monitoring by dynamic CT is necessary even in the absence of clinical symptoms.