Uhthoff's symptom in multiple sclerosis

A case report is presented in which a patient's initial complaint is of blurred vision after exercise (Uhthoffs symptom). Visual acuity and colour vision were found to be reduced after exercise. Additional neurological signs included homonymous scotomata and delayed visual evoked and somatosensory responses. Magnetic resonance imaging demonstrated multiple abnormal lesions in the brain. The significance of this symptom and its relationship to multiple sclerosis are discussed.     

Preliminary evidence for a role of apolipoprotein E alleles in identifying haemodialysis patients at high vascular risk

Conventional risk factors have very low predictive power in identifying haemodialysis patients at high risk of vascular accidents. A role for apolipoprotein E isotypes was looked for in a small, but rigorously defined, cohort of longterm haemodialysis patients. In individuals with high vascular risk, as identified by higher common carotid intima/media thickness, we found an excess of apolipoprotein E4 alleles. This preliminary result requires confirmation in large patient cohorts.      

A study of the influence of technical adequacy on the clinical result of moore hemiarthroplasty

The Moore and Thompson hemiarthroplasties are still commonly used for the displaced subcapital fracture in the elderly. The cemented Thompson has been claimed to be superior to the uncemented Moore prosthesis. However, the use of cement is associated with greater risks and the uncemented Moore appears to give good results in approximately two-thirds of patients.

The technical adequacy of uncemented hemiarthroplasty has rarely been considered in assessing the outcome. This study indicates that, on the basis of four radiological criteria, incorrect insertion of the prosthesis leads to a high chance of a poor clinical result at 6 months. Good results are more likely when the postoperative radiograph shows the prosthesis to have been inserted accurately. This is possible in most cases, except where the femur is grossly osteoporotic with a wide intramedullary canal. Uncemented hemiarthroplasty can produce satisfactory results but, like uncemented total joint replacement, is a more demanding procedure.     

Radiation-induced carcinoma of the penis

Two patients with carcinoma of the penis were treated with interstitial radiation. They were cured of their disease for 17 and 21 years respectively and then developed radiation-induced tumours.     

Toxicity of polycyclic aromatic hydrocarbons. III. Effects of beta-naphthoflavone pretreatment on hepatotoxicity of compounds produced in the ozonation or NO2-nitration of phenanthrene and pyrene in rats

Male Sprague-Dawley rats were treated ip with beta-naphthoflavone (BNF, 40 mg/kg/day) in dimethylsulfoxide (DMSO, 26.7 mg BNF/ml) for three days. At 24 hr after the pretreatment DMSO (3.0 ml/kg), phenanthrene (150 mg/kg), ozonized or nitrated products of phenanthrene (150 mg/kg), pyrene (150 mg/kg), or ozonized or nitrated products of pyrene (150 mg/kg) were injected ip. Phenanthrene, pyrene, and their ozonized or nitrated products were dissolved in DMSO (50 mg/ml). No increase in the level of aspartate aminotransferase (AST), alanine aminotransferase (ALT) or sorbitol dehydrogenase (SDH) was seen in the pretreated rats 48 hr after the treatment. This is in contrast to what was seen in previous work without the BNF pretreatment. BNF pretreatment induced a small but significant increase in gamma-glutamyl transpeptidase (GGTP) levels. No treatment group receiving BNF differed from another with respect to GGTP. A decrease in lactate dehydrogenase (LDH) levels was noted in the nitro-PAH treatment groups; the same phenomenon was observed earlier in rats treated with nitro-PAH without BNF treatment. These results suggest that the mixed-function oxidase systems specifically induced by BNF have a protective effect against the hepatotoxicity of the oxonized or nitrated products of phenanthrene and pyrene.     

The arden syntax for medical logic modules

The Arden Syntax for sharing medical knowledge bases is described. Its current focus is on knowledge that is represented as a set of independent modules that can provide therapeutic suggestions, alerts, diagnosis scores, etc. The syntax is based largely upon HELP and the Regenstrief Medical Record System. Each module, called a Medical Logic Module or MLM, is made of slots grouped into maintenance, library, and knowledge categories. The syntax has provisions for querying a clinical database and representing time. Several clinical information systems were analyzed and appear to be compatible with the syntax. The syntax has been tested for syntactic ambiguities using the tools lex and yacc. Seventeen institutions are currently in the process of adopting the Arden Syntax for their decision-support systems. A subcommittee of ASTM has been formed to develop standards for sharing medical knowledge bases. The Arden Syntax has been published by ASTM as a initial standard for sharing medical knowledge.