[Rheumatological care in the Rheumazentrum Ruhrgebiet Rheumatism Center-a model for conurbations]. / Rheumatologische Versorgung im Rheumazentrum Ruhrgebiet ­ ein Modell für Ballungszentren.

The Ruhrgebiet Rheumatism Center, which is highly specialized for rheumatic diseases, is the largest of its kind in Germany. For many years it has fulfilled all the requirements for structural quality required by the Association of Rheumatological Acute Clinics (VRA) including regular participation in the KOBRA benchmarking project. Therefore, the center regularly receives the VRA seal for quality of care. In 2018 more than 7500 patients were treated as inpatients. Within the framework of care according to §116b (ASV since May 2019) there were nearly 25,000 outpatient patient contacts. Furthermore, an early screening program (triage) was established 5 years ago in order to be able to identify patients with musculoskeletal complaints on a potentially inflammatory rheumatic basis. This functions in the sense of an early diagnosis and treatment in accordance with the treat-to-target concept within less than 4 weeks (initially) on an outpatient basis with respect to the required urgency, in order to subsequently provide sound diagnostic support. In the last 2 years 2017 and 2018, this deadline was met in more than 90% of cases. Within the scope of inpatient care approximately one third of patients were treated in recent years with a defined rheumatological complex therapy and 10% with pain complex therapy. Approximately 3% were treated with geriatric complex therapy and 65% were short-stay patients (<4 days), i.e. patients who received the necessary diagnostics and treatment on an inpatient basis at short notice. The overall structure of the rheumatism center, the cooperation with rheumatologists in private practice, many cooperation partners, referring physicians and patients represents a model for rheumatological care in large conurbations. The care of large numbers of patients also enables the further training of many assistants and this is essential for the future of good rheumatological medicine.

[Tubulointerstitial nephritis with uveitis (TINU) syndrome. A relatively rare rheumatological differential diagnosis with unexplained uveitis]. / Tubulointerstitielle-Nephritis-mit-Uveitis (TINU)-Syndrom. Eine eher seltene rheumatologische Differenzialdiagnose bei unklarer Uveitis.

The tubulo-interstitial nephritis and uveitis (TINU) syndrome, first described in 1975, is a rare disease most probably of autoimmune origin that is characterized by unilateral or bilateral uveitis and tubulointerstitial nephritis. Most patients are adolescents and it is sometimes associated with other autoimmune diseases, such as spondyloarthritis, rheumatoid arthritis and hyperthyroidosis. This article reports the case of a 43-year-old female patient who presented with refractory recurrent bilateral uveitis despite therapy with high doses of corticosteroids in combination with cyclosporin. When the patient was referred to this hospital for rheumatological examination after almost 1 year of therapy, mild renal insufficiency and proteinuria were found. The kidney biopsy revealed interstitial nephritis, partly crescent-shaped and partly chronic. A diagnosis of TINU syndrome was made and treatment with adalimumab in combination with methotrexate was started. The favorable clinical outcome indicated that tumor necrosis factor (TNF) alpha may play an important role in the pathogenesis of TINU syndrome.

[Radiation hygiene in medical X-ray imaging: part 2: Assessment of radiation exposure and radiation protection measures]. / Strahlenhygiene in der medizinischen Röntgenbildgebung: Teil 2: Expositionsbestimmung und Strahlenschutzmaßnahmen.

In order to secure and continually improve radiation protection standards in the field of medical X-ray imaging, the German X-Ray Ordinance requires that each individual examination be properly justified and that any procedure undertaken be optimized. Diagnostic reference levels have been introduced in Germany as a measure of optimization for common and/or high-dose X-ray procedures, and are regularly checked for compliance by the competent Medical Experts Office. A prerequisite for the implementation of these regulatory requirements is the determination of readily measurable dose quantities. They also form the basis for the estimation of organ doses and of the effective dose for exposure and risk assessment. The aim of this paper is to describe the essential dosimetric concepts and methods used for the assessment of radiographic, fluoroscopic, and CT procedures. In addition, practical measures for reducing the radiation exposure of patients and personnel will be discussed.

Neuronal activity in the periaqueductal gray and bordering structures during vocal communication in the squirrel monkey.

In seven freely moving squirrel monkeys (Saimiri sciureus), the neuronal activity in the periaqueductal gray (PAG) and bordering structures was registered during vocal communication, using a telemetric single-unit recording technique. In 9.3% of the PAG neurons, a vocalization-correlated activity was found. Four reaction types could be distinguished: a) neurons, showing an activity burst immediately before vocalization onset; b) neurons, firing during vocalization, and starting shortly before vocalization onset; c) neurons, firing exclusively during vocalization; d) neurons, firing in the interval between perceived vocalizations (i.e. vocalizations produced by group mates) and self-produced vocal response. All PAG neurons showed a marked vocalization-type specificity. None of the neurons reflected simple acoustic parameters, such as fundamental frequency or amplitude, in its discharge rate. None of the neurons reacted to vocalizations of other animals not responded to by the experimental animal. All four reaction types found in the PAG were also found in the reticular formation bordering the PAG, though in lower density.

Auditory frequency discrimination in the squirrel monkey.

Four squirrel monkeys (Saimiri sciureus) were tested for their frequency discrimination capacity using an eyeblink classical conditioning procedure, with air puff against the eye as unconditioned stimulus and 600-ms pure tones as conditioned stimuli. Absolute frequency difference thresholds showed a minimum (20-41 Hz, mean 30 Hz) at 4,000-8,000 Hz and increased towards higher as well as lower frequencies (70-90 Hz, mean 80 Hz at 300 Hz; 44-120 Hz, mean 82 Hz at 16,000 Hz). Relative frequency difference thresholds increased from higher to lower frequencies, with values as low as 0.3-0.8% (mean 0.5%) at 16,000 Hz and as large as 24-30% (mean 27%) at 300 Hz. The squirrel monkey's frequency discrimination function thus shows a severe deviation from Weber's law. The frequency difference thresholds are comparable to human's in the 4,000-8,000 Hz range, but are 65-80 times higher in the 500- to 300-Hz range. Individuals with high auditory thresholds do not necessarily also have high frequency difference thresholds.

Neuronal activity in the medulla oblongata during vocalization. A single-unit recording study in the squirrel monkey.

In six squirrel monkeys (Saimiri sciureus), the medulla oblongata was explored with microelectrodes, looking for vocalization-correlated activity. The vocalizations were elicited by microinjections of glutamate agonists into the periaqueductal grey of the midbrain. Vocalization-related cells were found in greater numbers in the nucl. ambiguus (Ab) and retroambiguus (RAb), in the parvocellular, magnocellular and central reticular formation as well as in the solitary tract nucleus and spinal trigeminal nucleus. Small numbers were also found in the vestibular complex, cuneate nuclei, inferior olive and lateral reticular nucleus. A differentiation of the neuronal responses into 12 reaction types reveals that the frequency of each reaction type varies from brain structure to brain structure, thus allowing a specification of the different vocalization-related areas. According to this specification, it is proposed that initiation of vocalization takes place via the parvocellular reticular formation; vocal pattern control is mainly brought about by the parvocellular reticular formation, Ab, solitary tract nucleus and spinal trigeminal nucleus; expiratory control and respiratory-laryngeal coordination is carried out by the RAb, Ab and central nucleus of the reticular formation; vocalization-specific postural adjustments are carried out via the vestibular and cuneate nuclei.

Vocalization-correlated respiratory movements in the squirrel monkey.

Respiratory abdominal movements associated with vocalization were recorded in awake squirrel monkeys. Several call types, such as peeping, trilling, cackling, and err-chucks, were accompanied by large vocalization-correlated respiratory movements (VCRM) that started before vocalization. During purring, in contrast, only small VCRM were recorded that started later after vocal onset. VCRM during trill calls, a vocalization type with repetitive frequency modulation, showed a modulation in the rhythm of the frequency changes. A correlation with amplitude modulation was also present, but more variable. As high frequencies need a higher lung pressure for production than low frequencies, the modulation of VCRM seems to serve to optimize the lung pressure in relation to the vocalization frequency. The modulation, furthermore, may act as a mechanism to produce different trill variants. During err-chucks and staccato peeps, which show a large amplitude modulation, a nonmodulated VCRM occurred. This indicates the existence of a laryngeal amplitude-controlling mechanism that is independent from respiration.

On the search for the vocal pattern generator. A single-unit recording study.

In the squirrel monkey (Saimiri sciureus), single-unit activity was compared between the midbrain periaqueductal grey and the parvocellular and central nuclei of the medullary reticular formation during the production of species-specific vocalization. It was found that all three areas contain neurones with vocalization-related activity. The relative number of specific reactions types differed between areas, however. While the majority of periaqueductal cells fired just before, but not during vocalization, most cells in the reticular formation fired before and during vocalization. Modulation of discharge rate with changing fundamental frequency was only found in the reticular formation, not the periaqueductal grey. It is concluded that the parvocellular and central nuclei of the reticular formation, but not the periaqueductal grey are involved in vocal pattern generation.

A morphological study of the cochlear nuclei of the pigeon (Columba livia).

The pigeon cochlear nucleus angularis (NA) and nucleus magnocellularis (NM) were analyzed with Golgi and Nissl techniques. NA was divided into a medial NAm and NA proper, which could be subdivided further into an intermediate NAi and lateral NAl. NAm contained a mostly homogeneous population of a unique multipolar cell type with very short dendrites and large somatic spines. NA proper contained four cell types: large, medium, and small multipolars, and medium bipolar. The medium multipolar cells were most common, and resembled the multipolar cells of the mammalian ventral cochlear nucleus. NM presented a homogenous appearance with a mediolateral gradient of cell size and shape. Medially located higher best frequency NM principal cells had round cell bodies with small somatic spines and few dendrites. By comparison, laterally located low best frequency NM stellate cells had more dendrites and spindle shaped cell bodies. The similarities between the cell types of NA and the cell types in the cochlear nuclei of other amniote vertebrates may be due to homology or convergent evolution.

Dual-channel telemetry system for recording vocalization-correlated neuronal activity in freely moving squirrel monkeys.

A miniature telemetric system is described which allows simultaneous measurements of neural activity and vocalization in freely moving monkeys within their social group. Single and multi-unit activities were detected with medium impedance electrodes that were fixed to self-made microdrives allowing accurate vertical positioning over a range of 8 mm. Vocalizations were registered by means of a piezo-ceramic device sensing the vocalization-induced skull vibrations. This allowed identification of the vocalizing animal in a larger group and eliminated environmental noise. Neuronal activity and vocalization were transmitted via separate channels of a FM transmitter using different carrier frequencies. The signals were decoded in two conventional FM receivers equipped with an automatic frequency control. The signals were stored for off-line analysis on a HiFi videotape recorder.

Simultaneous recording of slow brain potentials and transcranial magnetic stimulation of hand area in human motor cortex.

Recording of slow brain potentials (SPs) and transcranial magnetic stimulation (TCMS) of the human motor cortex were combined to probe the relationship between SP level and excitability of cortical neurons. In experiment 1, TCMS was applied during and shortly after the warning interval in a forewarned reaction time task. Electromyographic (EMG) responses to TCMS increased only slightly during the warning interval and were significantly elevated 150 ms after the imperative stimulus. In experiment 2, TCMS was applied during biofeedback-induced cortical positivity and negativity. In this non-motor task a dependence of TCMS response on SP amplitude was not significant. Results indicate higher local excitability of motor cortex during cortical negativity when a preparatory motor task is required. TCMS may better be suited to probe processes involved in motor tasks rather than non-motor and cognitive conditions.