Treatment of painful spondylolysis using Morscher's hook

An original technique of direct isthmic reconstruction described by E. Morscher was used in 25 patients with painful spondylolysis after failure of conservative treatment. After a follow-up of 25 months, the functional and radiological results were evaluated and compared with other techniques. Nineteen patients had an excellent or good functional result, in 2 patients the result was fair, and 4 patients had no beneficial effect on pain. The best results were seen in patients younger than 20 years, with an olisthy of less than 10 mm, without associated joint, disc or ligament pathology. In these cases, good results were achieved in 90%, and there was radiological consolidation in 100%.     

Calciphylaxis – a topical overview

'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis.     

In-vivo carcinogenicity of 2-nitro-oxaphenalenes

2-Nitro-oxaphenalenes are synthetic chemicals which were synthesized in the authors' laboratory. They are the most efficient mutagenic compounds on mammalian cells in culture. They are chemically related to the nitro-naphthofuran family by the displacement of the heterocycle on the naphthalene ring. Since nitro-naphthofurans have a strong mutagenic activity in bacterial tests without metabolic activation and are active in-vivo carcinogens, the purpose of this study was to demonstrate the carcinogenic activity of two 2-nitro-oxaphenalenes. The two compounds were injected s.c. into Wistar rats initially 6-weeks-old. They were dissolved in dimethylsulfoxide (DMSO) at a concentration of 1 mg/ml. A s.c. injection of 0.5 ml containing 0.5 mg of carcinogen was given once a week in the neck of each animal tested. Five control animals were not injected and five animals received 0.5-ml injection of DMSO every week to serve as a control. The animals developed tumors only at the site of injection. The tumors were classified as high grade fibrosarcomas. This experiment demonstrates that: (i) 2-nitro-oxaphenalenes are very active in-vivo carcinogens in rats; (ii) there is a good correlation between the high mutagenic activity especially in mammalian tests and the strong carcinogenicity of the compounds; and (iii) the presence of a 6-methoxy group increases by two-fold the carcinogenic potential.     

Anterior gastric stapling combined with posterior truncal vagotomy: an experimental technique for gastric acid reduction

An operative technique using a mechanical stapling device has been developed to simplify proximal gastric vagotomy. A series of gastric fistula dogs underwent posterior truncal vagotomy and anterior lesser curvature stapling. The basal and pentagastrin-stimulated acid secretion was measured before surgery and 2 weeks and 3 and 9 months after surgery. During the whole period, no change in body weight was noticed. Gastric acid secretion in dogs remained low and stable during the first year after the procedure.     

Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy

The dominant cone-rod dystrophy gene CORD6 has previously been mapped to within an 8 cM interval on chromosome 17p12-p13. The retinal- specific guanylate cyclase gene (RETGC-1), which maps to within this genetic interval and previously was implicated in Leber's congenital amaurosis, was screened for mutations within this family and in a panel of small families and individuals with various cone and cone- rod dystrophy phenotypes. A missense mutation (E837D) was identified in affected members of the CORD6 family, as well as a second missense mutation (R838C) in three other families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene to be implicated in cone-rod dystrophy and this is the first report of dominant mutations in this gene.      

Serum concentrations of oestradiol-17beta, progesterone, relaxin and chorionic gonadotrophin during blastocyst implantation in natural pregnancy cycle and in embryo transfer cycle in the rhesus monkey

The present study was undertaken to assess the temporal association between the profiles of serum concentrations of oestradiol-17beta, progesterone, chorionic gonadotrophin (CG) and relaxin in pregnancies established naturally, and after embryo transfer, as well as in failed pregnancies in rhesus monkeys. In naturally mated cycles (group 1) a conception rate of 75% was obtained. In group 1, the mean day of CG detection in serum was 11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day post-ovulation. In group 2, embryo transfer to synchronous, non-mated surrogate recipients was performed; seven embryo transfer cycles yielded three pregnancies which were allowed to continue to term and normal infants were delivered. In embryo transfer cycles the mean day of CG detection was 14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day post-ovulation. A delay of about 3 days was observed in the appearance in circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between natural mated and embryo transfer conception cycles. Significant differences (P < 0.05 for progesterone and P < 0.03 for oestradiol) were obtained for the areas under the curves for progesterone and oestradiol between days 12 and 16 in conception cycles compared with failed pregnancies. These data provide the first observation of the normal hormonal signals associated with maternal recognition of transferred embryos during the peri- implantation period, and suggest that the use of such an experimental primate embryo transfer model may help to elucidate components of maternal and embryonic signal-response mechanisms during embryo implantation.      

X-linked liver glycogenosis type II (XLG II) is caused by mutations in PHKA2, the gene encoding the liver alpha subunit of phosphorylase kinase

X-linked liver glycogenosis type II (XLG II) is a recently described X- linked liver glycogen storage disease, mainly characterized by enlarged liver and growth retardation. These clinical symptoms are very similar to those of XLG I. In contrast to XLG I patients, however, XLG II patients do not show an in vitro enzymatic deficiency of phosphorylase kinase (PHK). Recently, mutations were identified in the gene encoding the liver alpha subunit of PHK (PHKA2) in XLG I patients. We have now studied the PHKA2 gene of four unrelated XLG II patients and identified four different mutations in the open reading frame, including a deletion of three nucleotides, an insertion of six nucleotides and two missense mutations. These results indicate that XLG II is due to mutations in PHKA2. In contrast to XLG I, XLG II is caused by mutations that lead to minor structural abnormalities in the primary structure of the liver alpha subunit of PHK. These mutations are found in a conserved RXX(X)T motif, resembling known phosphorylation sites that might be involved in the regulation of PHK. These findings might explain why the in vitro PHK enzymatic activity is not deficient in XLG II, whereas it is in XLG I.