Radiographic appearance of artificially prepared periapical lesions confined to cancellous bone

Summary. Twenty artificial periapical lesions confined to cancellous bone were prepared at the apices of first and second mandibular molars of human cadavers. The lesions emphasized removal of the lamina dura and preparation of a 'halo' lesion surrounding the root apex, plus the addition of a simulated sclerotic border. Radiographs taken before and after creation of the lesions were scored by three examiners for detectable lesions Cross-sections of the lesions were assessed for the extent of bone destruction. Periapical lesions confined to cancellous bone were detected in 80 per cent of cases, and the presence of a sclerotic border tended to enhance visualization, although not in all cases. Intentional cortical involvement also improved detection of lesions. The anatomical features of the periapical area appear to promote the visualization of lesions which might not be detected in other locations.     

Disorders of language, communication, and behavior in mentally retarded children. Some ideas on their co-occurrence

The thesis of this article is that deficits in language and communication contribute to behavior problems in childhood. Mentally retarded children show a range of deficits in language and communication compared with normals; they are also at increased risk for behavior problems. The evidence suggests that these deficits are quantitative rather than qualitative. In addition, these linguistic deficits may contribute independently to the development of behavior disorders insofar as the linguistic deficit interferes with the child's ability to make himself understood or to understand others.     

Magnetic resonance imaging in planning limb-salvage surgery for primary malignant tumors of bone

In defining the linear extent of a malignant tumor in a long bone, radiographs, computerized tomography, and scintigraphy are routinely employed, especially when non-ablative surgery is being considered. The drawbacks of these modalities in defining the true intracompartmental extent of disease within a bone can largely be overcome with the use of magnetic resonance imaging. We did a prospective analysis of magnetic resonance imaging in sixteen consecutive patients with a primary malignant tumor of a long bone, and it showed that this modality has clinical promise of being more precise than the other modalities in defining the true proximal and distal extent of a tumor in a long bone. Coronal images permit easier planning of surgical techniques for salvage of a limb using an allograft than do a multiplicity of transverse images.     

Uncemented two-component femoral prosthesis for the hip joint. A 50-month follow-up study

The Monk Duopleet femoral interlocking uncemented two-component endoprosthesis consists of a polyethylene cup covered by a metal cap and an Austin-Moore type stem. Seventy-two patients (average age, 71 years) were treated by this arthroplasty: 27 for subcapital femoral neck fracture, 36 for osteoarthritis, and nine as an exchange operation. Three patients died following operation. After a mean follow-up time of 50 months, 47 patients were reexamined clinically and radiographically. Because of loosening, four patients had the prosthesis removed. Twenty-six patients were classified as excellent, 12 as good, six as fair, and three as poor. There were no cases of acetabular intrusion. The Monk Duopleet prosthesis may solve the problem of the loosening that had been associated with femoral component alone. The long-term results are promising and appear to be better than the results of the standard Moore prosthesis. The Monk Duopleet prosthesis is an alternative to other two-component endoprostheses for the treatment of subcapital hip fractures and in the group of patients suffering from osteoarthritis, where an arthroplasty with a cemented prosthesis may be considered hazardous because of age or general disease.     

Endogenous dopaminergic asymmetry affects development of seizures kindled in the rat amygdala

Cerebral dominance in 56 rats was determined by observing the direction of their turning behavior in response to injection of d-amphetamine (1.5 mg/kg, i.p.). Rats subsequently subjected to kindling of the amygdala developed full epileptic seizures after significantly fewer kindling sessions if the kindling electrodes were in the amygdala of the nondominant, rather than the dominant hemisphere. Kindling rate also showed a significant negative correlation with the total amount of turning after amphetamine. Rats kindled through electrodes in the ventral mesencephalon generally failed to develop full convulsive seizures, and did not show interhemispheric differences in the rate at which they developed preictal behaviors. As the dominant hemisphere of the rat, identified by rotational preference, contains a higher concentration of dopamine, we conclude that even small differences in dopaminergic activity, within the normal physiologic range, can affect the relative susceptibility of the two hemispheres to the development of kindled epilepsy.     

Total lymphoid irradiation in chronic polyarthritis--a new therapeutic concept

Eleven patients with refractory rheumatoid arthritis were submitted to a total lymphoid irradiation up to a dose of 20 Gy. A constant improvement of clinical symptoms was observed in four out of the eleven patients already during the treatment and in the other patients not later than two months after. The frequency of attacks decreased and the number of joints involved in the attack was reduced. Morning rigidity and joint swellings decreased. One patient developed joint empyemas 4 and 26 months after the treatment. Four patients died in the meantime. In two patients the cause of death were renal insufficiency and a postoperative cardiogenic shock associated with generalized amyloidosis. The third patient died because of a toxically induced left cardiac decompensation with sepsis that could not be controlled by antibiotic drugs and multiple joint empyemas. The fourth patient developed an abscess after surgical treatment of a Kaposi syndrome. She died three months later from acute left cardiac decompensation. The therapy induced a lymphocytopenia with decrease of T helper lymphocytes and unchanged number of T suppressor lymphocytes. The constant therapy results of total lymphoid irradiation in primary chronic polyarthritis is probably due to this modification in the immune regulation.