Cholesterol masses in association with spinal cord infarction due to intervertebral disc emboli

Summary The clinical and autopsy findings are presented from three dogs with spinal cord infarction. At autopsy firm gritty masses and cystic areas were present within the spinal cord. The masses contained numerous cholesterol clefts, collagen and reticulin fibres and were accompanied by a macrophage, giant cell and lymphocytic reponse. The cholesterol masses were present mainly in white matter. The ventral spinal artery or its branches as well as pial arteries contained fibrillary masses often covered by endothelial cells. The staining characteristics of these emboli suggested that they were fibro-cartilagenous and probably derived from the intervertebral discs. It is assumed that the cholesterol masses were formed from myelin breakdown products within infarcted areas.     

The pterygoideus proprius muscle

A bstract — An anomalous muscle was found in the infratemporal fossa of a male cadaver of advanced age. This formation passed between fixed bony attachments at the infratemporal crest (greater wing of the sphenoid) and the inferior part of the lateral pterygoid plate. The muscle was not atrophied but functional significance was not clear.     

The interaction of rheumatoid factor with hepatitis B surface antigen-antibody complexes.

A solid phase radioimmunoassay was developed in which the hepatitis B surface antigen was adsorbed to the surface of plastic beads. When the antigen-coated beads were incubated with human IgG antibody against hepatitis B surface antigen, immune complexes were formed on the solid phase surface. IgM rheumatoid factor was found to bind to the hepatitis B surface antigen-antibody complexes but not to the antigen or the IgG antibody alone. Since both hepatitis B surface antigen-antibody complexes and rheumatoid factor are commonly present in type B viral hepatitis, it is suggested that rheumatoid factor may play a role in the pathogenesis of this viral disease in man.     

Closure of colostomy—A safe procedure?

Summary A retrospective survey of a series of 73 patients undergoing closure of colostomy has been carried out. Closure was complicated in 37.8 per cent of cases, and fecal fistulas occurred in 17.6 per cent. The overall mortality rate of the procedure was 2.7 per cent. The underlying disease (carcinoma or diverticulitis) did not influence the complication rate. Furthermore, intraperitoneal and extraperitoneal methods of closure appeared equally satisfactory. Closure of colostomy within a month of construction was associated with an unacceptably high incidence of fecal fistula of 33 per cent.     

Association of low serum anticholinergic levels and cognitive impairment in elderly presurgical patients

Low-dose scopolamine, given as presurgery medication, resulted in low levels of serum anticholinergic activity and caused measurable cognitive impairment in 18 psychiatrically healthy elderly patients. The degree of impairment was directly related to serum anticholinergic activity levels and, in the small subgroup of patients scheduled for spinal anesthesia, to CSF anticholinergic activity. Two of the mental status tests used, the Rey Auditory-Verbal Learning Test and the Saskatoon Delirium Checklist, were sensitive enough to detect these mild drug-induced changes, while two other tests, the Mini-Mental State and the Symbol Digit Modalities Test, were not.     

Atenolol, methyldopa, and chlorthalidone in moderate hypertension.

Combined treatment with low doses of different drugs is widely used for moderate hypertension. The effects of atenolol and methyldopa at two dose levels and in combination at the lower doses were studied in patients with moderate hypertension on continuous treatment with moderate hypertension on continuous treatment with chlorthalidone. The mean reduction in standing blood pressures obtained with atenolol 150 and 300 mg/day was about 27/17 mm Hg and with methyldopa 750 and 1500 mg/day about 28/14 mm Hg. Combined treatment with atenolol 150 mg/day and methyldopa 750 mg/day for four weeks resulted in a reduction of 38/25 mm Hg. No difference was observed between the two doses of methyldopa. The lower dose of atenolol was better than the lower dose of methyldopa in reducing lying and standing diastolic blood pressures. These findings show that in patients on continuous treatment with chlorthalidone the addition of atenolol alone or methyldopa alone or of atenolol and methyldopa in combination is effective in the treatment of moderate hypertension.     

De microbiologische opleiding van personeel betrokken bij de bereiding van geneesmiddelen

Verslag van activiteiten m.b.t. dit onderwerp ontplooid door de Farmaceutische sectie van de Nederlandse Vereniging voor Microbiologie. Centraal hierin stond een Workshop Microbiologische opleiding en nascholing van personeel met middelbare en lagere opleidingen, gehouden 7 en 8 mei 1980 in het Radboudziekenhuis te Nijmegen.     

Localization of tetrodotoxin-sensitive field potentials of CA1 pyramidal cells in the rat hippocampus

1. The role of tetrodotoxin (TTX)-sensitive (Na+) channels in the generation of antidromic and orthodromic field potentials of the CA1 pyramidal cell population was examined by local application of TTX in the in vitro rat hippocampal slice preparation. 2. The sensitivity of alvear (antidromic) and stratum oriens (SO)-evoked potentials to TTX application (10-100 microM) was tested in stratum pyramidale and over the entire extent of pyramidal cell apical dendrites in stratum radiatum. Stratum radiatum (SR)-evoked potentials were examined at the level of pyramidal cell bodies and over the proximal 200 microns of the apical dendritic region. 3. Pressure application of TTX confined to stratum pyramidale or regions of stratum radiatum selectively blocked the negative component of antidromic and SO-evoked population discharge in the cell body layer and over the initial 200 microns of stratum radiatum. 4. SR stimulation evoked a complex field potential in the proximal stratum radiatum (less than 150 microns) composed of at least three components: 1) A short-duration (approximately 3 ms) negativity of shorter peak latency than the population spike recorded simultaneously in stratum pyramidale. This potential was highly sensitive to TTX and appeared to be instrumental in the generation of the cell body population response. 2) A long-duration negativity (approximately 20 ms) evoked at stimulation strengths that were subthreshold for both the short-duration negativity in proximal stratum radiatum and the cell body population spike. Although apparently less sensitive to TTX, this potential was reduced in amplitude with repeated TTX application; and 3) a slow (approximately 12 ms) positive-going potential that was only observed after eliminating all TTX-sensitive conductance mechanisms in the proximal stratum radiatum. 5. The latency difference between the SR-evoked short-duration negativity of proximal stratum radiatum and the population spike in stratum pyramidale decreased or reversed during the course of multiple discharge induced by the addition of bicuculline or picrotoxin (5-10 microM) to the perfusate. 6. These data indicate the presence of TTX-sensitive presumed Na+ channels over the initial 200 microns of pyramidal cell apical dendrites capable of supporting active conduction of population discharge evoked by antidromic or SO stimulation. The sensitivity of SR-evoked potentials to TTX suggests that a synaptic potential generated in the distal apical dendrites is capable of triggering both a slow active depolarization and a fast spike-like discharge in the proximal apical dendritic region.(ABSTRACT TRUNCATED AT 400 WORDS)