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The morphology of the minor fissure, i.e., the shape of the upper surface of the middle lobe, was studied in 10 specimens and in 60 thoracic CT's. In 8 specimens and 54 CT's there was the arrangement typical for the right lung consisting of 3 distinct lobes. The upper surface of the middle lobe had a convex upward shape against the base of the upper lobe in all anatomical preparations and in 52 of the CT's. The position and shape of the convexity was, however, quite variable. In 2 cases the upper surface of the middle lobe was flat. In 78% the minor fissure was incomplete and in 2 cases it was absent.

By employing the so-called inversion recovery technique, one has a nuclear magnetic resonance method at hand that allow discrete imaging of lesion in the intraorbital portion of the optic nerve in patients with optic neuritis. In our series, signal rich areas were visible in affected optic nerves in 15 of 18 patients. The areas of increased signal intensity involved the middle or the proximal third of the nerve and were still demonstrable following recovery of visual function. On the other hand, inversion recovery studies of the affected optic nerves following long inflammation free periods after an attack were within normal limits. Inflammatory edema or alterations in glial tissue may be considered as the causes of the increased signals.

The CT findings in the lungs of 52 patients with histologically confirmed sarcoidosis are described. In addition to a nodular pattern, reticulo-nodular, reticular, diffuse infiltrative and streaky shadowing due to fibrosis could be recognised. Pleural lesions, bronchial ectasis and mediastinal and hilar lymph node changes could be diagnosed. The high sensitivity of CT contrasted with its relatively low specificity. At present CT is useful for analysing the pulmonary pattern when planning lung biopsy or lavage. In some cases, the diagnosis of pulmonary sarcoidosis can be made by CT, but the exact criteria for diagnosis and differential diagnosis must be borne in mind.

Inversion recovery sequences with short inversion periods (STIR sequences) are particularly suitable for the examination of the intra-orbital and intracanalicular portion of the optic nerve, since they selectively suppress interference from neighbouring fat. This technique makes possible direct demonstration of retrobulbar neuritis that had to be diagnosed exclusively by clinical criteria up to now. As evidence of inflammatory changes in 15 out of 18 patients with acute retrobulbar neuritis, there were areas of increased signal intensity in the affected nerve; in six cases the nerve was also swollen. In eight normals and five patients with healed retrobulbar neuritis, the signal and calibre of the optic nerves were normal.

Articular dysfunction of the TMJ with anterior displacement of the disc ("internal derangement") is an entity which has been separated from other types of the "myofascial pain syndromes" and which can be treated conservatively or by surgery. Arthrography of the TMJ has contributed greatly to an understanding of normal and abnormal function and, in many cases, it can provide a diagnosis. On the basis of our experience with 80 investigations we discuss technical problems and the clinical indications. The indications for arthrography are in the pre-operative diagnosis, when clinical findings are uncertain, in order to demonstrate perforation, in order to confirm a suspected diagnosis and to assist in prosthetic treatment.

Thirty-four patients with known Paget's disease were examined by CT in order to characterise the appearances of the bones on transverse sections. The typical findings have been related to their anatomical localisation and frequency. The differential diagnosis from conditions with similar CT appearances, such as osteoplastic metastases, fibrous dysplasia or osteomyelosclerosis, is discussed. The CT appearances of Paget's disease are typical in the same way as conventional radiographs.

The structure of iremycin [10-(alpha-L-rhodosaminyl)-gamma-rhodomycinone] hydrochloride has been confirmed by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy. We studied the interaction of iremycin and the related compound daunomycin with DNA by transient electric dichroism and by sedimentation analysis of supercoiled closed duplex DNA. The apparent length increase of sonicated calf thymus DNA (150 +/- 20 base pairs) in 2.5 mM sodium cacodylate buffer (pH 7) at 12 degrees C was determined to be 0.40 +/- 0.02 nm/bound drug). The Cu(II) complex of iremycin with a metal/drug ratio of 0.7 induces a length increase of DNA of 0.44 +/- 0.02 nm/added drug. The alignment of the iremycin chromophore with respect to the DNA helix axis was determined from the electric dichroism of the complex. The tilt (long axis) and twist (short axis) of the chromophore are both 28 +/- 4 degrees, whereas for daunomycin the long axis is perpendicular to the helix axis and the short axis is twisted by about 25 degrees. Intercalation of iremycin between DNA base pairs is supported by unwinding of the supercoiled closed duplex form of pBR 322 plasmid DNA from Escherichia coli. In 2.5 mM sodium cacodylate buffer at pH 7 and at 25 degrees C, the unwinding induced by iremycin is 15.0 +/- 1.5 degrees/bound drug. Under identical conditions daunomycin shows on unwinding angle of 15.4 +/- 1.5 degrees. The superhelical density of pBR 322 DNA (sigma 0) was determined to be -0.087 +/- 0.002 at standard conditions (0.2 M NaCl, 37 degrees C).

The virulent phage Ta1 was obtained in good yields from infected cultures of Thermoactinomyces vulgaris 1227. The purified phage was found to sediment with a single band, the sedimentation constant being (519 +/- 14)S, and to exhibit a typical nucleoprotein behaviour in UV-spectrophotometric and CD experiments. The Ta1 phage consists of a hexagonal head about 0.056 micrometers in diameter and a very short tail. It is morphologically similar to the temperate Salmonella phage P22. The nucleic acid extracted from the phage was found to be a double-stranded linear DNA with a G+C content of 42 mole-% as deduced both from its melting temperature and buoyant density in CsCl. Analytical sedimentation revealed a high degree of molecular homogeneity of Ta1 Dna. the sedimentation constant of this DNA amounts to (35.9 +/- 0.3)S, corresponding to a DNA molecular weight of about 29 millions daltons. The biological activity of Ta1 DNA was indicated by its ability to infect the mycelium of the components T. vulgaris strain 1227 and to give rise to mature phages.

An arc welder of 32 years of age is presented with a random finding of miliar reticulonodular shadows in the plain film of the thorax. Subjectively and objectively the patient appears healthy. The presence of a pneumoconiosis is confirmed by biopsy. Differential diagnosis had to consider sarcoidosis and pulmonary siderosis in view of the known professional anamnesis. This case report underlines the reped demand to assess x-ray films of the thoracic organs only if the clinical findings and anamnesis are thoroughly known.

The temporomandibular joints (TMJs) of 60 patients with arthrographically confirmed internal derangements and 30 volunteers were examined with single photon emission computed tomography (SPECT). Semiquantitative evaluation was done by forming a quotient from the counts of a constantly sized TMJ-ROI relative to the overall counts of the cranium. The TMJ/cranium quotient depended on the age of the subject, with younger patients showing a larger quotient than older ones. Normal joints were separated from the afflicted ones by means of a discriminant analysis. Sensitivity of semiquantitative evaluation was 78% (disc displacements with reduction) and 89% (disc displacements without reduction). Correct visual evaluation was made in 53% of the reducing and 75% of the nonreducing discs. Semiquantitative SPECT of the TMJs provides important information on the extent of osseous changes in afflicted joints and is suitable for follow-up of splint therapy. It may also be helpful as a screening method in detecting clinically normal joints before arthrography is carried out and in assessing the presumptive response to treatment with a splint.

Thirty patients with histologically confirmed malignant schwannomas were examined. In five patients the lesions were malignant neurofibromas, as part of von Recklinghausen's disease, the others were solitary malignant schwannomas. CT appearances of malignant schwannomas are variable. Shape, structure and attenuation vary considerably. Most malignant schwannomas present with the CT criteria of benign tumours. Altogether neither the solitary schwannomas, nor those associated with von Recklinghausen's disease show specific diagnostic features, whether for the primary tumour or for recurrences. Reliable information on the nature of these lesions is possible in a few cases only.

SPECT examination of the TMJ using 99m Tc-MDP was performed in 43 patients with arthrographically proven anterior dislocation of the disc and in 30 normals. The results were evaluated visually and also in a semi-quantitative manner that took account of relative 99m Tc activity in the TMJ and of the age of the patient. In the presence of arthrographically proven anterior, but reversible, disc dislocation, the semi-quantitative method proved positive in 75% of cases (28 cases). In joints with fixed anterior dislocation (29 cases), bone changes were demonstrated in 86%. Visual evaluation was positive in 50% of reversible, and in 72% of non-reversible dislocations. Semi-quantitative SPECT of the TMJ is excellent for demonstrating bone reaction resulting from TMJ dysfunction and for indicating the severity of the joint abnormality.

The case of a seventy-year old lady is presented who, forty-five years ago, had dermal tuberculosis of the left lower limb and foot. After removal of the infected skin areas with an electric cauter the patient developed massive skin indurations, besides the typical scarification. Actual X-rays showed a decrease in seize of metatarsal bones and digits without lytic or porotic signs. Furthermore, dorsal luxation of the digits was visible. These alterations were interpreted as secondary bone remodelling resulting from long-term traction due to the extensive scarring.

Spectrophotometry, thermal denaturation, sedimentation, and viscometric techniques were used in a study of interaction of double helical DNA with an asymmetric phenazinium derivative, aposafranine. The results obtained indicate that aposafranine binds to DNA by a single binding mode, a wedge-like partial intercalation.

Twenty-six patients with suspected bronchiectasis were examined by bronchography and CT and the CT appearances of normal and abnormal bronchi are described. Like bronchography, CT will distinguish between cylindrical and cystic bronchiectasis. Lobar and segmental localisation can be reliably achieved by both methods; there was agreement between these methods in 109 out of 114 lobes and in 391 out 468 segments. In our experience the sensitivity of CT in the diagnosis of bronchiectasis is 93% and specificity is 96%. It is possible to obtain the necessary information, i.e. the existence and localisation of bronchiectasis by means of CT.

The binding to supercoiled plasmid DNA as well as to double-stranded short DNA fragments of the DNA binding protein. ASBIII, from S. hygroscopicus has been demonstrated by gel retardation asay. As further revealed by sedimentation analysis, the protein-DNA complex formation also involves condensation of DNA and an aggregation step at higher total protein-to-DNA ratio (w/w). In vitro studies of the transcriptional activity of DNA-protein complexes showed that the ASBIII protein inhibits the overall template activity in the RNA polymerase II system to nearly similar extents for various DNA's. Preincubation of ASBIII-DNA complexes of different GC content, however, suggested a selective inhibitory effect on GC-rich DNA due to the higher stability of this complex. The results also indicate that the initiation of transcription of the GC-rich DNA template is affected by the ASBIII protein. The present results on the DNA binding properties and inactivation of the transcription of the ASBIII protein suggest that this protein may be a potential candidate for the local compaction of chromosomal DNA in Streptomyces hygroscopicus.

Generalised lymphatic carcinosis, also known as lymphangitis carcinomatosa, cannot be diagnosed by just one x-ray film of the thoracic organs. However, if an enhanced reticular striated pattern is seen, possibly associated with miliar stippling or hilar masses it is recommended to perform short-term follow-ups and comparisons with previous x-ray films. Lymphangitis carcinomatosa becomes probable if rapid progression of the findings or development of new lesions is seen besides the already existing ones and if this is associated with rapidly increasing dyspnoea. Pulmonary tomography will not yield highly significant results, but it can substantiate the diagnosis, the same applies to computed tomography of the thorax. CT is particularly important in differential diagnosis. Earliest possible diagnosis of lymphangitis carcinomatosa is of great importance for therapy, since it may be a first pointer towards an unknown metastasising primary tumor or haematogenous dissemination of already known tumours.

The lacrimal drainage systems of 92 patients were examined by a digital subtraction technique; 30 patients were examined additionally by a conventional technique, using films obtained during screening for the contrast injection. The digital subtraction dacryocystogram provided excellent demonstration of the lacrymal sac and of the tear ducts, but there is little diagnostic gain when compared with the conventional technique. Both methods are highly reliable. In view of its low radiation dose and rapid and simple course, conventional dacryocystography is regarded as the method of choice for routine examinations. The digital subtraction technique should be reserved for special problems.

Magnetic resonance imaging (MRI) at 1.5 T was performed in 25 extracranial haematomas using spin-echo (SE) and fast-field-echo (FFE) sequences. The age of the haematomas was in 11 cases less than 2 days and in 9 cases more than 14 days. Fresh haematomas were isointense to skeletal muscle on T1-weighted SE images. With T2-weighted SE sequences, fresh haematomas had high signal intensity on the first day, but became inhomogeneous with predominantly low signal intensity on the following days. Areas of low signal intensity could be demonstrated by T2-weighted FFE sequences already on the first day after bleeding. Subacute haematomas were recognised by their high signal intensity on the T1-weighted SE images. Also with T2-weighted SE and FFE sequences, subacute haematomas showed increasingly high signal intensity. The characteristic appearance of haematomas facilitates their identification with MRI.

The paper reports on sedimentation and viscosity measurements performed on ultraviolet-irradiated DNA from T7 phage and calf thymus. From the hydrodynamic data the relative changes in the mean molecular weight, radius of gyration, and effective Kuhn statistical segment length were calculated. The results show that ultraviolet irradiation (254 nm) leads to a significant decrease of the effective statistical segment length of DNA which may be due to small local helix kinks (produced by the generation of photodimers) and a local increase of chain flexibility. Alterations in the overall DNA conformation may be observed even at low fluences where the mean molecular weight almost stays constant. The locally distorted helix regions possibly may serve as recognition sites in the first step of excision repair.

Percutaneous embolization using detachable balloons was successfully performed in a series of nine patients with intracranial carotid aneurysms. The clinical progress and the results of MR examination are reported. Up to 4 months after treatment, MR imaging did not show any significant change in size of the artificially thrombosed aneurysms. Complete resorption cannot be expected in less than 6-8 months, but resorption does eventually occur. The intensity pattern observed in the evolution of the thrombus was similar to that of intra- and extra-cranial hematomas.

A severe course of microlithiasis alveolaris pulmonum in a 28-year old patient is described. The disease, which had progressed to a very advanced stage at the time of examination, produced in the plain radiograph of the thorax an extensive, homogeneous, ground-glass like shadow of practically all organs of the thorax. The typical miliary (spot-like) shadow ("sandstorm lung") is visible only in the lateral and apical parts of the lung. CT revealed massive calcareous deposits which increased in craniocaudal and ventrodorsal direction. Bullous metaplasia of the lung was particularly striking in the apical region. No effective therapy is known so far. A combined heart and lung transplantation might be the only therapy that could prolong the patient's life.

We have found ultrasonography of the shoulder in differentiating between normal rotator cuff and rotator cuff lesion according to trauma a very helpful method. In comparison to arthrography it is a quick and painless method without any risk. Whereas other authors report a sensitivity of 100% and a specificity of 94% in shoulder disease we recommend ultrasonography in acute shoulder trauma as a screening method. Pathological findings in ultrasonography will make the decision for arthrography easy. The major diagnostic pitfall is the calcified tendon of the rotator cuff.

47 patients suspected of rupture of the rotator cuff were sonographed and arthrographed. Rupture of the rotator cuff was diagnosed in 12 cases, both diagnostic methods yielding the same result. In 29 patients sonography and arthrography did not reveal any abnormal findings. Six ruptures evident in sonography were not confirmed by arthrography and were considered false positive. Direct pointers towards rupture of the cuff would be: echoless defects, cuff cannot be visualised fully or in part, irregularities of movement during dynamic examination. Echoless "cystic" areas in the periarticular soft parts must be considered an indirect pointer. Echorich focal findings in the echopoor cuff represent a differential diagnostic problem and we cannot give a final assessment as yet. Shoulder sonography is justified as a screening method in suspicion of rotator cuff rupture before initiating arthrography. If sonography reveals no abnormal findings, shoulder arthrography need not be performed.

Acetabular fractures are caused by high kinetic energy, and satisfactory management requires differentiation of the fracture types. The basic radiological examinations consist of the A-P pelvic view, the obturator, and the iliac oblique view. Plain radiography proves to be insufficient, particularly for visualization of the posterior column and the posterior acetabular lip. In comparison, axial CT scans give exact and complete information about the acetabular fracture and associated injuries. In summary CT is the method of choice in evaluating dislocated or non-dislocated fractures, even when two- and three-dimensional reformation is involved.

In a prospective study, the findings on arthrography and CT in 51 TMJs with anterior meniscus dislocation were compared. The CT diagnosis of anterior dislocation was made by a standardised method which we have developed and which depends upon evaluating axial sections. Sensitivity of the CT methods was 87%. In the absence of arthrography, a negative diagnosis in the asymptomatic contralateral side was made in 81%. Ruptures and adhesions could not be demonstrated by CT. For these reasons, arthrography is to be preferred to CT for making the initial diagnosis. CT should be carried out for special indications, such as contrast sensitivity, the documentation of a clinically confirmed diagnosis and for follow-up of treatment. Currently an attempt is being made to stage the disease by computed tomography.

Some physico-chemical properties of the DNAs released from the actinophages SH3, SH10, SH11, and SH12 are described. The four phage DNAs have a linear double-stranded secondary structure and are unique with respect to their high G.C contents which, from melting studies and buoyant density experiments, were found to be in the range of 68-73 mol-%. The DNA molecular weights were determined by sedimentation velocity experiments and by electron microscopic length measurements, the mean values of the two corresponding data sets being 34.0 x 10(6) (SH3), 26.7 x 10(6) (SH10), 26.1 x 10(6) (SH11), and 28.7 x 10(6) (SH12) with a mean relative error of +/- 5%. From different observations it was concluded that SH10 DNA, and possibly also SH11 and SH12 DNA, have cohesive ends and can undergo intramolecular or intermolecular association to form ring-like monomers or linear and ring-like multimers. Cleavage of the DNAs of SH3, SH10, SH11, and SH12 by EcoRI restriction endonuclease delivered two, one, zero, and two cleavage sites, respectively, and by BamHI restriction endonuclease eight, zero, zero, and zero cleavage sites, respectively.