Lumbar facet joint tropism does not accelerate degeneration of the facet joints.

PURPOSETo study the relationship of lumbar facet joint tropism to degeneration of the cartilage and subcortical bone in the facet joints and the effect of tropism in intervertebral disk degeneration.METHODSThe orientation of 104 cadaveric lumbar facet joints with respect to sagittal plane was measured on CT scans, and the joints were classified as having no tropism, mild tropism, or severe tropism. On MR images, the severity of cartilage degeneration and bony sclerosis was measured. The correlation between tropism and degeneration was calculated, as was the relationship among age, spinal level, and degeneration.RESULTSWe identified four spinal levels with severe tropism, six with moderate tropism, and 94 without tropism. Cartilage degeneration was not significantly more severe in the joints with tropism than in the joints without. Sclerosis was slightly greater in the joints with tropism than in the joints without it. Sclerosis and cartilage degeneration were significantly related to age and spinal level.CONCLUSIONAge, spinal level, and overall facet joint angle are more important factors in facet joint degeneration than is tropism.     

High-resolution loading tests in the study of genetic heterogeneity in gangliosidosis fibroblasts

Summary GM₁- and GM₂-gangliosides were isolated from brain and radio-labelled. The labelled moieties were localized by hydrolysis with lysosomal enzymes, followed by thin-layer chromatography of the products. High-resolution loading tests with labelled gangliosides were developed and found to differentiate infantile and juvenile forms of GM₁- and GM₂-gangliosidoses as well as the identification of B, O and AB types of GM₂-gangliosidosis.     

Effects of hyperthermia on blood flow and cis-diamminedichloroplatinum(II) pharmacokinetics in murine mammary adenocarcinomas.

The effect of localized hyperthermia on blood flow and cis-diamminedichloroplatinum(II) (CDDP) pharmacokinetics in 7,12-dimethylbenz[a]anthracene-induced mammary adenocarcinomas was studied. Blood flow was determined in rat tumors and normal tissue immediately and 1, 2, and 3 h after local hyperthermia treatment (43 degrees C, 1 h) as well as in unheated tumors of rats. The rate of blood flow in the tumor was increased 1.9 times at the end of treatment relative to control values and returned to the control values by 3 h after hyperthermia. Similarly, the rate of blood flow in the peripheral skin around the tumor immediately after hyperthermia was 2.2 times greater than that of unheated skin and returned to near normal values by 3 h after heating. Tumor-bearing rats received CDDP 1 h before, at the beginning of, at the end of, and 1 h after hyperthermia administration. The CDDP plasma concentration versus time profiles for rats did not vary statistically between treatment groups. Two h after CDDP administration, the mean tumor CDDP concentration of the rats which received drug at the beginning of hyperthermia was statistically greater (P less than 0.05) than tumor CDDP concentrations in rats which received drug at the end of heat treatment. The latter group was given CDDP when tumor blood flow was the greatest; however, mean tumor drug concentration was lowest of all the groups. The mean drug concentration in tumor tissues of rats which received drug 1 h after hyperthermia was comparable to rats which received drug at the beginning of hyperthermia. This suggests that drug delivery or uptake in tumors may be altered when local hyperthermia is administered concurrently or sequentially.     

Does the Extent of Surgery Make a Difference in High Grade Malignant Astrocytoma?

This paper examines the effect of patient age, tumour grade and extent of surgery on the outcome of treatment of 278 patients with high grade malignant gliomas referred to the Queensland Radium Institute between 1980 and 1987. The aim was to determine whether the extent of surgical resection alters survival rates. The extent of surgery had no effect on survival except for those patients with grade 3 tumours in whom a total excision was possible. Those in whom only a biopsy was done did not have a worse prognosis. Grading was found to be of importance, as patients with grade 3 tumours had a better survival than those with grade 4 tumours. In grade 4 tumours, those under 30 years of age had a better survival than those over 30 years, whereas with grade 3 tumours there was a gradation of age effect (under 40 years best, then 40–49 years, and those 50 years and over doing worst).     

Evidence for the presence of a type III secretion system in diffusely adhering Escherichia coli (DAEC).

Diffusely adhering Escherichia coli (E. coli) strains (DAEC) represent a potential cause of diarrhoea in infants, and the detection of type three secretion system (TTSS) genes in DAEC would substantiate their pathogenic nature. In this work, four isolates of DAEC, recovered from stools of diarrhoeic children, were analysed by PCR, in order to detect the presence of TTSS genes. Primers targeted to the escC, escJ, escN and escV, some of the most conserved TTSS genes in enteropathogenic and enterohaemorrhagic Escherichia coli (EPEC and EHEC), were used in order to verify the occurrence of homologous genes in our DAEC isolates. By this approach, we were able to characterise DNA fragments corresponding to putative escJ and escN genes in all DAEC isolates. Furthermore, DNA fragments homologous to the escC and escV genes were also amplified from all isolates. Besides the similarity found among the DAEC esc homologues with EPEC and EHEC esc genes, the nucleotide sequence analysis of the flanking regions of the amplified DNA fragments suggests that the putative DAEC esc genes are organised in the same manner as observed in EPEC and in EHEC strains. The results described here provide strong evidence for the presence of a TTSS in the DAEC strains analysed, implicating a pathogenic nature of these isolates.     

Psychophysiological activity and neuropsychological test performance in alcoholics.

This study examined electromyogram (EMG) and skin conductance level (SCL) as mediators of neuropsychological test performance of alcoholics. Alcoholics and controls with high EMG performed less well than low EMG subjects on 12 measures of neuropsychological performance. For SCL, the alcoholics and controls in the Low Group did not differ from those in the High Group on any measure. Analyses that used information intake (Low EMG and High SCL) and rejection (High EMG and Low SCL) information postures (IPs) demonstrated that the intake group outperformed the rejection group on 10 neuropsychological measures. Subjects with intake IPs reported more stimulation, concentration, and interest during the tasks than did subjects with rejection IPs. Results suggest that IPs can be used to identify alcoholics with neuropsychological deficits.