Intracerebral hemorrhage after carotid endarterectomy

A series of 14 patients with intracerebral hemorrhage after carotid endarterectomy is reviewed. This complication occurred in 0.6% of 2362 consecutive carotid endarterectomies performed at the Mayo Clinic from 1972 through 1986. All hemorrhages occurred within the first 2 weeks after operation and were ipsilateral to the side of the operation. Eight patients died, and only two made a good recovery. Significant risk factors are hypertension and chronic hemispheric hypoperfusion with impaired autoregulation. The "normal pressure-hyperperfusion breakthrough" syndrome was considered to be operative in 12 of the 14 patients. Nine patients had documented hyperperfusion (at least 100% increase of baseline cerebral blood flow) at the time of surgery. In an additional three patients, normal perfusion-pressure breakthrough was inferred by the clinical course and radiological findings, as well as by the absence of alternative explanations. Patients at risk for postendarterectomy intracerebral hemorrhage include those who have a clinical history suggestive of hemodynamic cerebral ischemia, severe carotid stenosis with limited hemispheric collateral flow, and postendarterectomy hyperperfusion, as measured by intraoperative cerebral blood flow. To minimize the risk of hemorrhage in these patients, strict maintenance of blood pressure at normotensive or even relatively hypotensive levels during the intraoperative and early postoperative periods is advised.     

Age and simple reaction time: decade differences for 5,325 subjects

In a booth at a public exhibition entitled "Medicines for Man," 5,325 men, women, and children carried out a 1-minute test of simple reaction time (RT) with 1 to 10 second randomized variable preparatory interval (PI). They recorded their ages by decade. Average RT over the last eight (of ten) trials increased progressively from the 20s up to age 60 and over, and downward to the teens and under 10s. The single fastest RT in each test varied much less with age, only the 20s being clearly faster than the rest, with the under 10s slower. Within-subject variability of RT was increased only in the under 10s and over 60s. Ability to sustain attention during the longer PIs may underlie the gross average RT differences with age, and possibly some more basic neural property the superiority of the 20s in fastest RT.     

Normal perfusion pressure breakthrough complicating surgery for the vein of Galen malformation: report of three cases

Three cases are described of infants who developed malignant brain swelling (and in one case hemorrhage) after surgery for vein of Galen malformations. The cause for the brain swelling was felt to be due to hyperperfusion, or the "normal perfusion pressure breakthrough" syndrome. Although well-described for cerebral parenchymal arteriovenous malformations, cases of this complication occurring in vein of Galen malformations have not previously been reported. It is concluded from these cases that infants with large arteriovenous shunts, as attested by cardiac failure and cerebral atrophy, have an increased risk of developing this complication.     

Effect of margins of excision on recurrence after local excision of ductal carcinoma in situ of the breast

AIMS: To determine important factors influencing recurrence after local excision of duct carcinoma in situ (DCIS) of the breast. MATERIALS AND METHODS: The extent (size) in millimetres, classification (by cytonuclear grade (NHSBSP system), by extent of necrosis, and by the Van Nuys system), and excision margins of 115 cases of screen detected DCIS treated by local excision were measured. A prognostic index was calculated by the addition of the Van Nuys classification (low grade, 1; moderate grade, 2; high grade, 3), margin score (> or = 10 mm, 1; 1-9 mm, 2; < 1 mm, 3), and size score (< or = 15 mm, 1; 16-40 mm, 2; and > or = 41 mm, 3), giving a total score of 3-9. RESULTS: Classification using cytonuclear grade, extent of necrosis, or the Van Nuys system did not correlate significantly with recurrence. The excision margin (in millimetres) was associated with recurrence (p = 0.027) and if excision margin status was simplified using the scoring system (> or = 10 mm, 1; 1-9 mm, 2; < 1 mm, 3), the margin score was significantly associated with recurrence (p = 0.03). A prognostic index based on the Van Nuys score, margin status, and size was significantly associated with recurrence (p = 0.003). CONCLUSION: The results support the hypothesis that the margin of excision is the most important factor predicting the recurrence of DCIS after local excision.     

Evaluation of an enzyme-linked immunosorbent assay for the detection of herpes simplex virus antigen.

An enzyme-linked immunosorbent assay (ELISA) kit for herpes simplex virus developed by Ortho Diagnostic Systems, Inc., was evaluated. In phase I experiments, 263 clinical specimens from genital lesions were extracted into serum-free medium and then tested by ELISA for herpes simplex virus antigen. The results were compared with those obtained by conventional viral culture. Of 83 specimens, 65 were positive by ELISA (sensitivity, 78.3%). In phase II experiments, 249 clinical specimens were tested for herpes simplex virus antigen in direct specimen and in cell cultures (MRC-5 and rabbit kidney) incubated for 2, 4, and 7 days. Of 63 specimens, 40 were positive by ELISA in the direct specimen (sensitivity, 63.5%), and by 7 days incubation, 100% of the cultures positive by viral cell culture were also positive by ELISA. The ELISA was reproducible, and when both the direct detection and amplification culture were used, the sensitivity of ELISA paralleled the diagnosis of herpes simplex virus infections by viral cytopathic effect.     

Production of delayed hypersensitivity by antigen associated with peritoneal exudate cells and the effect of pretreatment with Freund's complete adjuvant

The immunogenicity of antigens associated with peritoneal exudate cells was compared with the immunogenicity of free antigens for the induction of delayed hypersensitivity. Oil induced peritoneal exudate cells were incubated with antigens labelled with radioactive iodine, washed and injected intraperitoneally into recipient guinea-pigs. Comparable amounts of free antigens were also injected. All sixteen inbred guinea-pigs given human or bovine gamma-globulin associated with peritoneal exudate cells gave positive reactions (greater than 5 mm) while the eighteen guinea-pigs given free antigens failed to show a reaction. Similar results were obtained with serum albumins in inbred guinea-pigs. The increased immunogenicity of antigens associated with peritoneal exudate cells was also seen in outbred guinea-pigs.

Pretreatment with Freund's complete adjuvant did not depress the immunogenicity of antigens associated with peritoneal exudate cells and actually increased the induration of the 24-hour reaction to picrylated human serum albumin and human serum albumin associated with peritoneal exudate cells.

     

Reduced high-energy phosphate levels in rat hearts. I. Effects of alloxan diabetes.

Significant alterations in heart carbohydrate and lipid metabolism are present 48 h after intravenous injection of alloxan (60 mg/kg) in rats. It has been suggested that uncoupling of oxidative phosphorylation occurs in the alloxanized rat heart in vivo, whereas normal oxidative metabolism has been demonstrated in alloxan-diabetic rat hearts perfused in vitro under conditions of adequate oxygen delivery. We examined the hypothesis that high-energy phosphate metabolism might be adversely affected in the alloxan-diabetic rat heart in vivo. Phosphocreatine and ATP were reduced by 58 and 45%, respectively (P is less than 0.001). Also, oxygen-dissociation curves were shifted to the left by 4 mmHg, and the rate of oxygen release from blood was reduced by 21% (P is less than 0.01). Insulin administration normalized heart high-energy phosphate compounds. ATP production was accelerated in diabetic hearts perfused in vitro with a well-oxygenated buffer. These studies support the hypothesis that oxidative ATP production in the alloxan-diabetic rat heart is reduced and suggest that decreased oxygen delivery may have a regulatory role in the oxidative metabolism of the diabetic rat heart.     

Radioprotective potential of ginseng

A majority of potential radioprotective synthetic compounds have demonstrated limited clinical application owing to their inherent toxicity, and thus, the seeking of naturally occurring herbal products, such as ginseng, for their radioprotective capability has become an attractive alternative. In general, ginseng refers to the roots of the species of the genus Panax. As a medicinal herb, ginseng has been widely used in traditional Chinese medicine for its wide spectrum of medicinal effects, such as tonic, immunomodulatory, antimutagenic, adaptogenic and antiaging activities. Many of its medicinal effects are attributed to the triterpene glycosides known as ginsenosides (saponins). This review addresses the issue of the radioprotective effects of ginseng on mammalian cells both in vitro and in vivo. Results indicate that the water-soluble extract of whole ginseng appears to give a better protection against radiation-induced DNA damage than does the isolated ginsenoside fractions. Since free radicals play an important role in radiation-induced damage, the underlying radioprotective mechanism of ginseng could be linked, either directly or indirectly, to its antioxidative capability by the scavenging free radicals responsible for DNA damage. In addition, ginseng's radioprotective potential may also be related to its immunomodulating capabilities. Ginseng is a natural product with worldwide distribution, and in addition to its antitumor properties, ginseng appears to be a promising radioprotector for therapeutic or preventive protocols capable of attenuating the deleterious effects of radiation on human normal tissue, especially for cancer patients undergoing radiotherapy.