The influence of neonatal thymectomy on the development of radiation myelopathy in rats.

To investigate the possible contribution of cellular immunity in the development of radiation injury of the central nervous system, Wag/Rij rats were thymectomized at birth and irradiated to the cervical spinal cord at the age of 3 months. At the time of paralysis or at the end of the follow-up period (when rats were 1-year-old) the animals were sacrificed and the mediastinum was examined histologically. In 95% of the neonatally thymectomized animals no thymus was left. These rats showed a firm impairment of the cellular immunity, as they had a 40% reduction of the T-lymphocytes in the spleen, and a 70% reduction of the mixed lymphocyte reaction, compared to age-matched controls. Both single dose and two-fraction irradiation experiments were performed. No modification of the latency time to develop paralysis was observed comparing thymectomized and age-matched controls. The incidence of foreleg paralysis after cervical spine irradiation (single dose or two-fraction) was identically distributed in the follow-up period for both neonatally thymectomized and control Wag/Rij rats. The ED50 value derived in the single dose experiments was 20.3 Gy for the control animals, and 20.9 Gy for thymectomized rats, and in the two fraction experiments 29 Gy for controls and 29.6 Gy for thymectomized rats. None of these differences are significant. It appears that neonatal thymectomy, in spite of its firm suppression of the cellular immunity, has no major influence on the development of radiation myelopathy in rats.     

Komplikationen nach arthroskopischer Rotatorenmanschettennaht

Rotator cuff tears are increasingly treated arthroscopically, preferentially with suture anchors since a stable anchorage in bone is possible, simple and rapid. However, the restricted view, especially with longer operating times, conceals a danger of misplacement. Such risks can be determined rapidly with experience and should be corrected as soon as possible, e.g. through a change to open procedures. In our case report, the migration of a metal anchor could be corrected in a later operation and a revision of the re-rupture was then carried out using mini-open technique.     

Rechtsprechung aktuell

Ohne Zusammenfassung     

Chirurgie der differenzierten Schilddrüsenkarzinome

Die 5-Jahres-überlebensrate von differenzierten Schilddrüsenkarzinomen ist generell sehr gut und betr?gt 80 – 95%. Hierbei bestehen Abh?ngigkeiten zum Alter des Patienten [15], zum prim?ren Tumorstadium, zur histologischen Differenzierung und zum Ausma? der region?ren und Fernmetastasierung [6]. Patienten mit Tumorfreiheit haben ebenfalls eine bessere Prognose gegenüber denen mit einem Resttumor. Dies spricht für ein konsequentes Vorgehen beim Prim?reingriff mit Thyreoidektomie und Entfernung der Lymphknoten des zentralen Kompartments. Stadienadaptiert schlie?t sich eine Radiojodtherapie oder die Kombination mit einer externen Radiatio an. Bei der Reoperation differenzierter Schilddrüsenkarzinome mu? zwischen der individuellen Prognose des Patienten, dem Ziel der Operation und der postoperativen Morbidit?t/Mortalit?t entschieden werden. Aufgrund des hohen Risikos sollten diese Operationen in Zentren durchgeführt werden, so da? postoperative Komplikationen (permanente Recurrensparese/Hypoparathyreoidismus) vertretbar gering gehalten werden k?nnen (Tabelle 11). Dennoch sollte nicht au?er Acht gelassen werden, da? individuell bei differenzierten Schilddrüsenkarzinomen im Stadium pT1 auch ein eingeschr?nkt radikales Vorgehen (Hemithyreoidektomie) ohne Verschlechterung der Prognose m?glich scheint. Strenge Nachuntersuchungsergebnisse und Ergebnisse weiterer klinischer Studien müssen hierzu abgewartet werden.     

Correction of camptodactyly with an external fixator

Camptodactyly is a flexion deformity of the proximal interphalangeal joint. Because of unsatisfactory results, treatment is not recommended for mild deformities, and in severe deformities surgery has been disappointing. A specially designed external fixator providing gradual distraction was used in a severe case. With this mildly aggressive method, an acceptable result was obtained. Received: 5 June 1997/Accepted: 2 February 1998     

Morphological study of neocortical areas in Rett syndrome

Various neocortical areas from four females aged 16–24 years with Rett syndrome (RS) were investigated and compared with brains of therapy-resistant partial epilepsy (TRPE) patients (18–25 years), infantile autism (IA), and control brains (24 and 58 years). The cytoarchitecture of area 10 (frontal), area 21 (temporal), area 4 (primary motor cortex), and area 17 (primary visual cortex) was studied by the combined Klüver-Barrera (luxol fast blue and cresyl violet) standard procedure. Autofluorescence of lipofuscin, immunofluorescence of synaptic vesicle proteins [synaptophysin (p38)] and lectin-stained (Wisteria floribunda agglutinin) perineuronal nets (PNs) were studied in the cortices using dual-channel confocal laser scanning microscopy. The brains of RS females show various types of morphological/cytoarchitectonical abnormalities of single pyramidal neurons in layers II–III, and V–VII of different cortical areas. The abnormalities include mild losses of pyramidal neurons, more pronounced in layers II and III than in layers V and VII, and more evident in frontal and temporal areas than in the visual cortex. Microdysgenesis, including abnormalities due to neuronal migration disorders, was not found in RS, in contrast to the observations in TRPE patients, strongly indicating that RS is not a neuronal migration disorder. Lipofuscin distribution was normal but amounts were lower in RS cases than in control and TRPE brains. PNs were less expressed in cortices of the IA case, but were clearly overexpressed in the motor cortex of RS. Quantitative analysis of p38 showed a decrease in the area occupied by p38 immunoreactivity by 20–40% in RS compared with controls. It is concluded that RS could best be explained by a postnatal synaptogenic developmental deficiency; the basic defect, however, is still completely unknown. Received: 26 February 1996 / Revised, accepted: 11 July 1996     

Cellular and humoral reactivity pattern to the mycobacterial heat shock protein HSP65 in adjuvant arthritis susceptible and resistant Wistar rats.

We have analyzed the cellular and humoral immunity to the mycobacterial 65 KDa heat shock protein (hsp65) in a group of Freund's Adjuvant-immunized rats with a limited susceptibility to Adjuvant arthritis. According to the arthritis indices during the period of study (35 days), two different groups of rats could be distinguished; a) autoimmune Adjuvant arthritic rats (AA), and b) Non-arthritic animals (NA), including both rats which did not display any disease symptoms and rats suffering mild transient inflammation. The cellular response to the immunizing agent (Mycobacterium tuberculosis) or the mitogen Concanavalin A was comparable between both groups of rats. However, we detected an impaired cellular response to the individual hsp65 antigen in the animals that did not develop the disease. On the contrary, the level of hsp65-specific antibodies was much higher in NA animals than in AA rats suggesting a protective role for the hsp65 specific antibodies.