Structure and evolution of the compact radio source in NGC 1275.

Investigations of the fine-scale structure in the compact nucleus of the radio source 3C 84 in NGC 1275 (New General Catalogue number) are reported. Structural monitoring observations beginning as early as 1976, and continuing to the present, revealed subluminal motions in a jet-like relatively diffuse region extending away from a flat-spectrum core. A counterjet feature was discovered in 1993, and very recent nearly simultaneous studies have detected the same feature at five frequencies ranging from 5 to 43 GHz. The counterjet exhibits a strong low-frequency cutoff, giving this region of the source an inverted spectrum. The observations are consistent with a physical model in which the cutoff arises from free-free absorption in a volume that surrounds the core but obscures only the counterjet feature. If such a model is confirmed, very-long-baseline radio interferometry observations can then be used to probe the accretion region, outside the radio jet, on parsec scales.

Upper limit of 3.3 astronomical units to the diameter of the galactic center radio source sgr a*.

Sagittarius (Sgr) A(*) is a unique radio source located at the center of our galaxy. The radiation from Sgr A(*) may be generated in matter accreting onto a massive black hole. In observations at long wavelengths, the apparent angular size of Sgr A(*) decreases in the manner expected for emission from a point source scattered by electron density fluctuations along the line of sight. Measurements at a wavelength of 7 millimeters with the nearly completed Very Long Baseline Array indicate a size of 0.7 milliarc seconds, which is consistent with an extrapolation from results at longer wavelengths. The true size of Sgr A(*) must be less than 0.4 milliarc seconds, or 3.3 astronomical units. The inferred black hole mass is less than 1.5 x 10(6) solar masses according to a recent model for the emission.

Follow-up studies in a case of unusual congenital myopathy, suggestive of nemaline type.

A 20-month-old boy--offspring of consanguinous parents, whose mother presumably had subclinical myopathy--presented with clinical signs of congenital non-progressive myopathy, neurogenic-myogenic electromyographic findings and normal motor conduction velocity. Biopsy of quadriceps muscle showed fiber-type disproportion with hypotrophic type 1, hypertrophic 2A and absent 2B fibers. Subsarcolemmal segmental foci of abnormally, in part regularly arranged bundles of mostly thin myofilaments were found in 13% of hypotrophic type 1 fibers. Rods were seen in only 1 fiber out of 20 tissue blocks. Reexamination 6 years later revealed slightly increased muscle force, myopathic EMG pattern and borderline motor and sensory nerve conduction velocities. Biopsy specimen from deltoid muscle consisted of untypable fibers of varying diameters with jagged Z-lines and increased variability of myofibrillar diameters. Multiple rods were present in 1% of the fibers, the formerly seen segmental foci in 0.1% only. Several intramuscular nerves were normal. The case contributes some new features to the spectrum of congenital myopathies of the nemaline type and suggests different stages of arrested maturation of type 1 fibers at least in this particular case.

[Concept, monitoring program and results of ambulatory care of children with meningomyelocele (spina bifida)]. / Konzept, Untersuchungsprogramm und Ergebnisse der ambulanten Betreuung von Kindern mit Meningomyelozelen (Spina bifida).

The ambulant long term care for children with meningomyeloceles requires the interdisciplinary cooperation of pediatricians, pediatric neurologists, surgeons, orthopedists, radiologists and psychologists, social workers, physiotherapists and orthopedic mechanics. We present the concept for our out-patient consulting hour for 154 children and adolescents with meningomyeloceles, meningoceles and other forms of paraplegia, and the program of medical examinations for the detection of urologic malformations and the consequences of neurogenic disturbance of bladder function, neurologic complications (seizures, tethered cord etc). and dysfunction of liquor shunts. Additional items are the control of physiotherapy and the regular and adequate prescription and inspection of orthoses. The rate of complications is presented: revision of shunts 60%, seizures 17%, cerebral abnormalities 16%.

[Value of mobile long-term EEG in epileptology in childhood]. / Zum Stellenwert des mobilen Langzeit-EEG in der Epileptologie des Kindesalters.

By means of a portable cassette recorder system (Medilog, Oxford Medical Electronics) the electroencephalograms of 31 children were recorded continuously over 24 up to 72 hours. In 6 epileptic children improvement of their anticonvulsive therapy were achieved. Of 25 children supposed to be epileptic 14 turned out to suffer from non-epileptic attacks; in 8 of them useless anticonvulsant therapy already had been installed and could be abolished. In 9 children the diagnosis remained uncertain, mainly because there were no seizure-like events throughout the registration period. Indications for and limitations of the long term EEG cassette recording are discussed on the basis of the available literature.

The very long baseline array.

The Very Long Baseline Array is a high-resolution synthesis radio telescope consisting of ten antennas, each 25 meters in diameter, located throughout the United States from Puerto Rico to Hawaii. Each antenna will be equipped with low-noise receivers spaced throughout the frequency range from 330 megahertz to 43 gigahertz, a hydrogen-maser frequency standard for time and frequency reference, and broadband digital tape recorders. Tapes recorded at each antenna will be simultaneously replayed and correlated in a specially built digital correlator, and the correlator output will, by Fourier transformation, be used to construct images of celestial radio sources with an angular resolution better than one thousandth of an arc second.

A deep 6-centimeter radio source survey.

The Very Large Array has been used to survey a small region of sky at a wavelength of 6 centimeters down to a completeness level of 60 microjanskys-about 100 times weaker than the faintest radio sources that have been detected with other instruments. The observed source count at flux densities below 100 millijanskys converges in a manner similar to the lower frequency counts, although there is some evidence for an excess of sources weaker than 100 microjanskys. The sources in the survey are preferentially identified with faint galaxies.

Intracranial arteriovenous malformations and aneurysms in childhood and adolescence.

Clinical data of 19 arteriovenous malformations (AVM) and 15 aneurysms (AN) are presented. Combined clinical, neurophysiological and neuroradiological follow-up studies have been carried out on the surviving patients (14 AVM and 10 AN). Two patients with multiple AN had coarctation of the aorta. Three AVM of the Vein of Galen showed typical symptoms within the 1st year of life, all other lesions became evident later than 5 years of age. In the acute phase of the disease clinical history and neurological deficits of AVM and AN tend to be very similar. Subarachnoid hemorrhage with or without intracranial hematoma is the most frequent initial symptom. A CT scan is valuable as a first orientating investigation but morphology and operability of the vascular lesion is only demonstrated by angiography. The prognosis of AVM and AN is promising as soon as the first critical period has been survived. AVM patients show significantly less severe residual neurological and psychiatric defects than AN cases. EEG-follow-up studies and CT scans are helpful for controlling residual functional and morphological cerebral damage in survivors.

Problems of live virus vaccine-associated poliomyelitis a paralytic case with isolation of all three poliovirus types.

The case of a 4-month-old girl is described who developed a paralytic polio-like syndrome 3 weeks after oral polio vaccination (OPV). All three poliovirus types could be isolated (9 days after onset of disease polio type 2, and 33 days after onset of disease types 1 and 3, respectively). In order to classify these isolates as Sabin (vaccine)-like (SL) or non-Sabin-like (non-SL), several markers were tested in three laboratories [intratypic serodifferentiation, reproductive capacity at supraoptimal temperature (RTC), Al(OH)3 gel elution assay, and oligonucleotide mapping]. The results of the marker determinations were not uniform, but--summarizing all data--it seems plausible to associate the disease with the OPV. The significance of marker determinations in proving a vaccine-induced poliomyelitis is discussed in the light of this clinical case. Some comments are made on poliovirus vaccination policy in developed countries.

[Encephalitis of the basel ganglia associated with mumps]. / Stammganglien-Enzephalitis nach Mumps.

Two weeks after epidemic parotitis a 10-year old boy developed an acute extrapyramidal syndrome together with pyramidal tract signs but without impairment of consciousness. The CSF showed mild pleocytosis. The CT of the brain exhibited a well defined circumscribed and symmetrical swelling and hypodensity of the basal ganglia and of the internal capsule. Only slight and transient dysrhythmia was to be found in the EEG. Therapy with Prednisolone, Biperidene and Tiapride resulted in regression of symptoms. But one year later rigor and pyramidal tract signs remained evident in spite of intensive physiotherapy and logopaedic measures. Residual symmetric atrophia of the basal ganglia became evident in the CT by dilatation of the anterior horns of the lateral ventricles caused by lacking of the vault of the caudate nuclei heads.

[Positive ventriculography and computer assisted tomography of the skull in the evaluation of megalocephaly in newborns and infants (author's transl)]. / Computertomographie und positive Ventrikulographie in der Diagnostik des Makrozephalus bei Neugeborenen und Säuglingen.

To clarify indications and limits of computer assisted tomography and positive ventriculography the results of both methods were compared with each other retrospectively in 55 macrocephalic newborns and infants. It could be shown that positive ventriculography, even if combined with coronal views, was superseded by computer assisted tomography to only a certain extent. To complete the appropriate diagnosis preoperatively positive ventriculography was necessary most often in patients with paranatal disturbances who had undergone intensive care treatment. The non-invasive method of computer assisted tomography often yielded sufficient information on localisation, size, and nature of the underlying pathologic process. Both methods turned out to be complementary when topographical and functional interrelations of cranial cysts had to be demonstrated, especially structures of the midline and of the posterior fossa, which could not be visualized by computer assisted tomography alone.

Ventriculography with positive contrast medium in early infancy.

42 ventriculographies (PV) were carried out in infants between 10 days and 10 months of age using positive contrast medium. Indications, technique of PV and complications are discussed; PV is compared with CT and it is concluded that PV is a simple method of clarifying the causes of a macrocephalus in infancy without great technical effort and that the roles of CT and PV are valuable diagnostic modalities which are complementary.