Human amyloid-beta1-42 applied in vivo inhibits the fast axonal transport of proteins in the sciatic nerve of rat.

Human amyloid-beta1-42 has been suggested to be a pathogenetic factor in Alzheimer's disease. The precise mechanism by which this peptide causes the degeneration of neurons in the affected brain is not yet fully understood. By using immunohistochemistry we explored the inhibitory effects of human amyloid-beta1-42 applied in vivo on the fast axonal transport of acetylcholinesterase, the amyloid precursor protein, the vesicular acetylcholine transporter and synaptophysin in the sciatic nerve of rat. Our findings provide evidence for the in vivo neurotoxic effect of human amyloid-beta peptide.

Vulnerability of small GABAergic neurons to human beta-amyloid pentapeptide.

beta-Amyloid peptide (A beta), the principal component of senile plaques in Alzheimer's disease, has been found to be neurotoxic. The role of A beta in the deficits of the GABAergic system in patients with Alzheimer's disease is unclear. It has been suggested that the cytotoxic activity of A beta is localized to amino acid residues 25-35 of this peptide, which contains a total of 42 amino acid residues. We now report that the short amyloid peptide fragments corresponding to amino acids 31-35 (A beta 31-35) and 34-39 (A beta 34-39) are also toxic in vitro to the small GABAergic neuron population of basal forebrain cultures. Morphological changes were accompanied by an increased number of varicosities localized on the processes of the GABA-immunoreactive neurons and by the appearance of round cells without processes. The neurodegeneration was confirmed by means of scanning electron microscopy. Quantification of the morphological findings by image analysis demonstrated a size-related dependence of the degeneration of GABAergic neurons. The results suggest that fragments of A beta shorter than A beta 25-35 may exert cytotoxic action and demonstrate the toxicity of these A beta fragments in decreasing the number of small GABAergic neurons.

Muscle-pedicle grafts or muscle-pedicle-bone grafts in the treatment of avascular necrotic femoral heads.

The paper is a microangiographic study of the revascularisation of experimentally devascularised femoral heads in rabbits. We examined the revascularisation process in muscle pedicles implanted into the devascularised femoral heads. Two forms of pediculated grafts were used: muscle-pedicle grafts and muscle-bone-pedicle grafts. The pedicles were formed from the gluteal muscle. The end of the muscle-bone-pedicle graft was formed by a small piece of trochanter major. The revascularisation process was quicker in the case of the pure muscle-pedicle grafts, and it was delayed in muscle-bone-pedicle grafts, which can be explained by the morphological differences between the two forms. A 2-week delay was observed during the 12-week observation period. A quicker process may mean better progress of revascularisation.

[Management of idiopathic femur head necrosis in adults using Sugioka's femur-osteotomy method]. / Az idiopátiás felnöttkori combfejelhalás kezelése Sugioka-féle femur-osteotomiával.

Authors report on the results achieved with Sugioka's osteotomy in 20 cases. In the stage III or less and if the damage of the femoral head was less than 100 degrees, the result of the operation was good or excellent. The operation performed with adequate indication proved to be effective.

[Girlestone's arthroplasty with resection of the femur head in the management of infection as a complication of hip prosthesis]. / Girdlestone szerinti combfej-resectios arthroplastica a csípöprotézisek infekt szövödményeinek gyógyításában.

From the endoprosthesis material with early and late complication and treated with Girdlestone's method (resection arthroplasty of the femoral head) n 36 cases, 27 were available for follow-up after 1-11 years (in average 5 years). The assessment was made with an own point-system. 3 categories were differentiated on the base of these points. From the 27 patients 7 were satisfied, 14 "reconciled", 6 dissatisfied. It could be stated that Girdlestone's operation does not mean a catastrophe, as the major part of the patients has no pain and sinus, is able to walk and to make the domestic work and is not reduced to the care of others.

[Results of surgical treatment of Dupuytren's contracture]. / Ergebnisse nach operativer Behandlung der Dupuytren'schen Kontraktur.

Ninety-five Patients with Dupuytren's contracture, treated by partial (subtotal) aponeurectomy, have been evaluated retrospectively from various points of view. The immediate postoperative status and the results one to five years later were compared. The authors establish that Dupuytren's contracture can be treated with very favourable effect, but the good results deteriorate later due to recurrence. This deterioration remains temporarily unchanged in the second and third years, but the worsening continues till the end of the fifth year. The functional state shortly after the operation was 41% better than the preoperative one, becoming 18% worse after the fifth year, but even then was 22.6% better than the preoperative condition.

Morphological investigations of a porous aluminum oxide ceramic and the consequences for clinical application.

The ingrowth of bone and the tissue compatibility of a Hungarian aluminum-oxide ceramic have been investigated in animal experiments by microscopic section, by electron microscopy, and with energy-dispersion X-ray microanalysis. Surrounding bone grew into the 100- to 500-micron pores of the porous ceramic without any undesirable reaction, as well as into bored holes 500 micron in diameter. It is technically possible to make only the 1- to 2-mm deep superficial layer of such a material macroporous, so that it can be applied as an acetabular component of hip prostheses; if the surrounding bone grows into the macropores of this thin layer (as was shown in our experiment) it can perfect the connection between the living bone and the non-living ceramic material without essentially changing the much required, positive qualities of a solid acetabular component. The authors intend to apply this material in this way.

Bone growth accelerated by stimulation of the epiphyseal plate with electric current.

The effect of stimulation with continuous small amounts (20 microA) of electric current on the distal epiphyseal plate of rabbit femurs was examined. In contrast to control animals 6 weeks after the operation 18 of the 20 experimental animals showed an increased lengthening or broadening of the femur on the operated side. In 14 cases the increased growth resulted in varus or valgus deformities.

[Our corrective osteotomy for radius fractures healed in defective position at the typical spot]. / Unsere Korrekturosteotomie in Fehlstellung geheilter Frakturen der Speiche an der typischen Stelle.

Authors give literary survey about correction possibilities of Colles fractures healed in failed position. In their paper the procedure of their clinic reviewed: with oscillating saw a wedge is removed from the radius on place of the failed fracture and so the normal angles of the radiocarpal joint can be restored. But at the same time the ulna must also be shortened with removal of a segment from the distal part. Both bones will be fixed laterally with ASIF semi-tubular plates. Results were evaluated with the McBride point system. From 23 cases 22 were available for follow up examination. 8 cases were "excellent", 13 "good", 1 "fair". There was no "bad" among the cases. Our favourable results support advantages of this method.

[Repositioning and retention problems of calcaneus fractures]. / Zu den Repositions- und Retentionsproblemen der Kalkaneusfraktur.

A new procedure is elaborated by the authors: the treatment of impression-fractures of the calcaneus. Exact repositioning is considered to be important. For this purpose, an apparatus for repositioning was constructed. The authors discuss the manoeuvres for exact repositioning. The repositioned fracture can be fixed well by two divergent ASIF cancellous bone screws to be inserted percutaneously after predrilling from the tuber calcanei. The stability of the osteosynthesis makes external fixation with plaster superfluous. This statement is based on the good results of 63 calcaneus fractures treated in this manner.

[Late results of severe flexor tendon injuries of the hand after producing tendon-sheath from a vein (author's transl)]. / Spätergebnisse nach künstlicher Sehnenscheidenbildung aus Venen bei Beugesehnenverletzungen der Hand.

In 1975 one of the authors published a new procedure of reconstruction of severe flexor tendon injuries in the Verdan 2 Zone: a flexor-tendon plasty combined with the reconstruction of tendon sheaths from a vein. In a follow-up study of 54 cases the authors evaluated results from 1-6 years perspectively by means of two methods. Two thirds of their cases are classified as "excellent" or "good". The evaluation by means of two methods provides interesting comparisons. The authors support the evaluating method of Buck-Gramcko, Dietrich and Gögge, and they particularly stress the necessity of registering preoperative states in evaluating results of the flexor tendon injuries.