Anatomical assessment of iliac crest graft size for anterior spondylodesis.

Standard procedure for monosegmental anterior spondylodesis often combines anterior stabilization with autologous iliac crest graft. Recent publications defined a minimum size of the graft as a technical specification for this procedure. The cross sectional area of the graft to be transplanted should be at least 23.9% of the cross sectional area of the vertebral bodies to be fused. We investigated whether the required minimum size of autologous graft, as identified both experimentally and clinically, is compatible with the anatomical conditions in central european patients. Computed tomography scans (n = 348) of polytraumatized patients were obtained in the course of initial diagnosis. The scans were evaluated for vertebral body size and the possible size of autologous bone graft in the region of the anterior superior iliac crest. The evaluation of 348 CT scans demonstrated that 95% of the quantified iliac crest grafts would achieve the size recommended for anterior spinal fusion between T10 and T12. In 90% of all cases the planned iliac crest graft exceeded the size limit of 23,9% between concerning the endplates T10 and L2. In 85% the planned iliac crest graft exceeded the size limit of 23,9% between T10 and L3. The recommendation to take this value into account for monosegmental anterior spondylodesis should gain in importance in clinical practice.

Immune mechanisms in the process of hepatopathies chronicization. Contribution and role of lymphokines.

The study attempts to evaluate the role of interleukin-6 (IL-6) in the pathogenesis of chronic hepatitis. We have used EIA sensitive methods to determine the serum concentration in patients with chronic active hepatitis of HB (+) (CAH-HE Ag+) antigen, with chronic active hepatitis of HB(-) (CAH-HBAg-) antigen and in those with persistent chronic hepatitis of HB(+) (CPH-HBAg+) antigen, compared with a group of controls (blood donors) in whom HBAgs, antiHBs, HBAge, antiHBe and anti HBc were absent. Disease status diagnosis was given in accordance with international conventions, immunologic tests included. The fact that the T lymphocytes with a CD56 are present in the liver and that same marker is also encountered on the Kuppfer cells, but not on the T lymphocytes in circulation, shows that in the liver the interleukin 6 is produced by the activated T lymphocytes and by the Kuppfer cells. Therefore, in such conditions, LB stimulation and growth is performed rather by IL-6 and to a lesser extent by IL-8. This statement is also supported by the finding that in the lymphocyte cultures in the peripheral blood there is no difference in the response to polyclonal mitogens between patients with CAH-HBAg(+) and those with CAH-HBAg(-). Also, there are no significant differences in the total immunoglobulin concentrations, but there are differences in the IgM concentration (greater in CAH-HBAg(+). In our investigations, the serum level of IL-6 (40.1 +/- 6.8 pg/ml) was higher in those with higher immunoglobulin concentrations-both IgG, but more particularly IgM. The IgM increase was correlated with the presence of HBAg. Therefore, the highest IL-6 values were found in CAH with HBAg(+). Increases of serum IL-6 concentrations were found during intervals of severe hepatic aggression manifested in a cytolitic syndrome, with transaminase increase. In the case of determinations in dynamics, the values decreased as the enzyme titre decreased. We can state that the serum activity of IL-6 reflects the degree of liver inflammation and can be used as a parameter for monitoring the disease.

Voluntary multiplet discharge after the activation test for spasmophilia as an electromyographic sign of a mild form of this disease.

The electromyographic (EMG) diagnosis of spasmophilia is based on the appearance in a susceptible muscle of spontaneous burst (multiplet) discharges after an activation procedure consisting usually in 10 minutes ischemia followed by a pause of a length that varies with the author but does not exceed 5 minutes, and finally by a hyperventilation, again not exceeding 5 minutes. In investigations carried out many years ago we observed that a number of subjects with symptoms of spasmophilia showed no postischemic spontaneous bursts, but responded with bursts to voluntary contraction. In this work we present some findings leading to the conclusion that voluntary burst discharge after the activation procedure can represent a sign of spasmophilia and not a mere manifestation within normal limits. Thus, in most cases with no symptoms of spasmophilia, voluntary burst response was absent. On the other hand, most subjects with such an EMG alteration suffered of troubles attributable to spasmophilia. Crisis of tetania with partial or generalized contracture could be encountered in such cases with a frequency close to that of cases with mild spontaneous burst discharge, being, on the contrary, exceptional in cases with normal EMG. In a previous work we showed the existence of a close correlation between the increase above normal of the incidence of ischemic discharge and the intensity of postischemic spontaneous burst (multiplet) discharge. A significant increase of ischemic discharge was also found for the cases showing only voluntary bursts (34.29% of 487 cases as compared to 14.28% of 602 normals). In addition, the period of abnormal burst responses of motor units to voluntary command was significantly prolonged for the cases with more intense ischemic discharge. Finally, there is no gap between spontaneous and voluntary burst discharge, since not rarely a short contraction could trigger a rhythmical selfmaintained burst discharge entirely similar to the spontaneously occurring one. One may conclude that voluntary burst discharges, if rather persistent, can represent a sign of spasmophilic alteration of excitability that must be always tested EMG in suspected cases that give no spontaneous burst discharge to the facilitation procedures. It represents a change in excitability less severe than the spontaneous burst discharge.

Electrical activity induced by ischemia in the skeletal muscle of patients with spasmophilia.

The incidence of spontaneous electrical activity during ischemia was studied in normal and spasmophilic subjects with a Bronk electrode inserted in the first dorsal interosseous muscle. Subjects were of both sexes, aged 16 to 65 years. The diagnosis of spasmophilia was established electromyographically by a variant of the Alajouanine test. Ischemia induced in many cases an electrical activity consisting of discharge potentials that have the amplitude, duration and morphology of motor unit potentials. The number of discharging motor units varied, sometimes leading to an electrical Trousseau associated to a carpal spasm. The discharge of individual motor units was irregular and practically uninfluenced by passive manipulations on the muscle or voluntary contraction. The activity started usually 30 sec to 1 min after the onset of ischemia, reached a maximal intensity (as to the number of motor units and frequency of discharge) in about 1 min and declined gradually in the following minutes. This activity was encountered in 55.06% of 770 cases of spasmophilia and only in 11.66% of 283 normal subjects, with a tendency to more intense discharge in spasmophilia. Its incidence in the spasmophilic group was closely related to the intensity of spontaneous repetitive discharges appearing electromyographically after the activation test, reaching 78.63% in most severe cases. The behaviour was interpreted as indicating a higher susceptibility in spasmophilia of axons to depolarization induced by hypoxia. This higher susceptibility appears as an important component of the excitability alterations leading to the complex neuromuscular disorders occurring in spasmophilia.

A comparative study of the immunogenicity of some penicillins and of their cross reactions.

The immunogenicity of four penicillin preparations was comparatively investigated by titration of penicilloyl (PO) specific hemagglutinating antibodies found in sera of rabbits inoculated with equimolecular amounts of these penicillins incorporated in Freund incomplete adjuvant. Benzylpenicillin (BP) was shown to be endowed with the highest immunogenicity, while oxacillin (OX), ampicillin (AM) and Amoxil (AX) were found significantly less immunogenic. By examining comparatively the titers of hemagglutination reactions given by the sera of each animal with erythrocytes coated with the penicillin used for its immunization as well as with the other penicillins investigated, important cross immunological reactions were found in all of the cases. Interestingly, the cross reactions produced by AM- and AX-specific antisera with heterologous penicillins were apparently higher than the reactions obtained with the homologous penicillin. No significant differences were found concerning the ability of the four penicillins to form PO conjugates with BGG. Thus, the differences in immunogenicity exhibited by the four penicillin preparations may not be explained in this way.

Spontaneous formation of immunogenic conjugates by a biotransformation product of sulfanilamide.

3-hydroxy-sulfanilamide (3-HS) has been previously shown to be formed in significant amounts in rabbits and humans treated with sulfanilamide. In the present paper we demonstrate that 3-HS reacts readily with proteins at alkaline pH and forms conjugates capable to induce hapten specific antibodies in rabbits. According to our previous observations on ortho-aminophenol (OAP), the haptenic properties of 3-HS are apparently due to the presence in its molecule of an ortho-aminophenolic structure, rendering it capable to form a highly reactive quinoneimine derivative. In spite of a similar mechanism of linking and of the presence of an ortho-aminophenolic structure in the two haptens, 3-HS and OAP immunological systems do not cross react with each other. The data presented here support the hypothesis that 3-HS may represent the hapten or one of the haptens involved in sulfonamide allergy.

Spontaneous formation of immunogenic conjugates by ortho- and para-aminophenol.

Ortho-aminophenol (OAP) and para-aminophenol (PAP) react readily with proteins at alkaline pH giving rise to conjugates capable to induce hapten specific antibodies in rabbits. PAP and OAP immunological systems do not cross react with each other, but both anti-PAP and anti-OAP serum give intense cross passive hemagglutination reactions with hydroquinone and pyrocatechin conjugates prepared by the same procedure. PAP immunological system does not cross react with various systems of the "para" group in which the conjugates were prepared by diazotization. PAP proved unable to induce formation of specific antibodies when inoculated in Freund adjuvant into rabbits and both PAP and OAP were unable to sensitize erythrocytes by incubation at alkaline pH. The findings are discussed in the light of data from literature showing that some drugs with amino aromatic structure are transformed in the body into compounds with PAP or OAP structure which might be able to form immunogenic conjugates with autologous proteins in vivo.

The discrepancy between the inhibitory activity induced on passive hemagglutination by the free and conjugated hapten. The significance of the phenomenon for the explanation of the drug allergy.

The capacity of the free and conjugated haptens to inhibit passive hemagglutination has been comparatively studied in five immunological systems, using hapten specific antisera prepared in rabbits and conjugates of the respective haptens with rabbit serum proteins. The results demonstrate that the affinity of the free hapten for the specific antibodies is 100 to 10,000 times lower than the affinity of the conjugated hapten. This finding constitutes an explanation for the occurrence of the allergic drug reactions under the circumstances where the concentrations of the free hapten are much higher than the concentrations of the hapten bound in in vivo formed conjugates. Using the passive hemagglutination inhibition test, the affinity of the various forms of a given hapten for the specific antibodies can be comparatively evaluated.

The effect of a high-voltage electric fiedl on neurosecretion and on certain diencephalic protein fractions in the rat.

Exposure of Wistar male rats to an electric field of 100 lV/m for 120 minutes produced intense mobilization of the neurosecretory material in the supraoptic and paraventricular nuclei and significant changes in some protein fractions of the hypothalamus, pineal body and neurohypophysis. The significance and possible mechanisms of these effects are discussed.