Steroid regulation of pituitary LH and FSH secretion in the male may be mediated via the direct action of testosterone, or via the conversion of testosterone to either dihydrotestosterone (DHT) or estrogenic steroids. The site of testosterone conversion to these metabolites may be peripherally and/or centrally located. The purpose of this study was to investigate the importance of the conversion of testosterone to estradiol in the control of gonadotropin secretion using the aromatase inhibitor aminoglutethimide (AG). In testosterone-implanted orchidectomized dogs, AG prevented the ability of testosterone to inhibit the post-orchidectomy rise of LH, despite the presence of normal plasma concentrations of both testosterone and estradiol. These data suggest that aromatization of testosterone to estradiol is a necessary step in the regulation of LH secretion. Furthermore, a lack of change in the peripheral concentrations of estradiol in the presence of AG led us indirectly to conclude that inhibition of aromatization occurred centrally rather than peripherally. In the absence of AG, testosterone was unable to maintain intact levels of FSH in the orchidectomized dog for more than six days. Thus, it still remains to be demonstrated whether steroids are of major importance in the regulation of FSH secretion.

Aminoglutethimide↗

PubMedDate not supplied

Synthesis of hydantoins via N,N'-ureas derived from polymer-bound amino acids.

Starting from carboxy-linked amino acids on trityl functionalized polystyrene resin a highly efficient solid-phase synthesis of hydantoins via N,N'-ureas was elaborated. The polymer-bound hydantoins can be used as a scaffolds for further combinatorial transformations, such as alkylation. Cleavage from the resins yielded the corresponding hydantoins in good yields and purities as shown by ESI-MS and HPLC.

Adsorption↗

PubMedDate not supplied

[Clinical and radiological isthmus reconstruction in lumbar spondylolysis and minimal spondylolisthesis].

Treatment of spondylolysis and minor form of spondylolisthesis in childhood is usually conservative and includes physical therapy, a temporary reduction in sport activities or the use of an orthosis. Persisting pain despite conservative therapy, neurological symptoms and progressive sliding on x-ray may indicate surgical treatment. We report about the results in 25 patients operated by direct repair of the isthmus between 1982 and 1990 in the Orthopaedic Hospital in Mannheim. In 75% of the cases the special hook-screw by Morscher was used. The other patients were operated according to the original method described by Buck or by the Scott procedure with wire fixation. The clinical and radiological results were available in all patients by a mean follow-up of 8.9 years (4-12 years). All juvenile patients had good or very good clinical results. Within the adult group half of the patients had fair or worse clinical results. Only in 3 out of 14 cases we found bony consolidation of both arches. In 6 cases the x-ray showed pseudoarthrosis on both sides. In 3 of these patients spondylodesis had to be performed. Because of the bad results of direct repair in adult patients, we looked for further criteria, which are necessary to achieve good clinical and radiological results. In addition of the age, the condition of the disc is important. In adolescent patients (more than 16 years old) we documented a degeneration of the disc by NMR or by intraoperative discography.

Adolescent↗

PubMedDate not supplied

[Pyogenic spondylitis in the interarticular portion of the vertebral arch. Case report on primary dorsal spondylitis].

The manifestation of a pyogenic spondylitis only in the dorsal part of a spinal segment is very rare and causes even more diagnostic problems than the typically anterior located spondylitis. We are reporting on a patient with known isthmic spondylolisthesis who developed the inflammatory process primarily in the intervertebral joint and in the interarticular portion. For a few months the cause of his complaints was thought to be due to spondylolisthesis till radiological adn laboratory methods lead to the correct diagnosis and adequate therapy.

Abscess↗

PubMedDate not supplied

[Osteochondroma as an unusual cause of metatarsus primus varus].

A solitary osteochondroma of the metatarsale II of an adolescent is presented which led to a painful Metatarsus primus varus. After resection of the tumor the patient was free of symptoms, the postoperative resulting form of the foot was normal. One should be aware of a tumor as a possible cause of foot deformities.

Adolescent↗

PubMedDate not supplied

[Dislocation fracture with transverse spinal lesion caused by a seat belt injury in infant].

A 21 month old child suffered from a luxation fracture L 1/2 with a complete paraplegia caused by an incorrect used car fastened seat belt. After operative reduction and stabilisation with Harrington-implants there was a slow but nearly complete recovery of sensible and motor functions. Three years after the accident there is only a low grade deformity in the upper lumber spine.

Accidents, Traffic↗