Ultrastructure of capillary permeability in human brain tumor: primary meningeal malignant melanoma

The tumor vessels of a primary meningeal malignant melanoma were studied by electron microscopy. There were numerous endothelial fenestrae and basal lamina abnormalities in the intrinsic tumor capillaries. They resembled the tumor vessels found in nonglial tumors, but were distinctly different from those seen in glial tumors with nonfenestrated capillaries. These findings were anticipated because leptomeninges have fenestrated capillaries.     

Expression of human epidermal growth factor and its receptor in esophageal cancer

The expression of human epidermal growth factor (hEGF) was examined immunohistochemically in 86 esophageal cancer lesions, comprising 67 primary tumors and 19 metastatic lymph nodes. In the normal esophagus, the parabasal and intermediate cell layers showed a weak expression of hEGF, however, hEGF-positive tumor cells were detected in 62 (92.5 per cent) of the 67 primary esophageal carcinomas and in 18 (94.7 per cent) of the 19 metastatic lymph nodes. In this study, the immunoreactivity of hEGF was classified into 4 grades according to the number of stained tumor cells. A significant correlation was observed between the histologic type and the grade of hEGF immunoreactivity (Chi-square test, p less than 0.01). hEGF immunoreactivity in well differentiated squamous cell carcinomas was significantly higher than in other squamous cell carcinomas, although there were no correlations between other pathological findings and hEGF immunoreactivity. Patients with hEGF immunoreactivities of grades II or III had much worse prognoses than those with grades 0 or I (p less than 0.05). In 22 esophageal carcinomas and 10 normal esophageal mucosae, EGF receptor (EGFR) contents were measured by the competitive binding assay. The average EGFR content (101.3 +/- 35.7 fmol/mg protein, mean +/- SE) of the esophageal carcinomas was significantly higher than that (5.3 +/- 1.2) of the normal esophageal mucosae (p less than 0.05). Moreover, in hEGF negative tumors, EGFR contents were lower than in hEGF positive tumors. These results suggest that hEGF and EGFR show increased production in squamous cell carcinomas and could to be useful prognostic factors in patients with esophageal cancer.     

Severe lightning pain during spinal anesthesia

A 74-yr-old man was scheduled for the biopsy of prostatic tumor under spinal anesthesia. Preoperative serologic test for syphilis was highly positive. Spinal anesthesia was performed in the sitting position, and 2 ml of hyperbaric Neo-percamine S (a mixture of 0.24% dibucaine and 0.12% T-caine) was administered uneventfully with the onset of warm sensation on the perineal region. Ten minutes later, however, he began to complain of severe lightning sensation on the feet. After giving pentazocine intravenously, the short cystoscopic procedure was completed. As a cause of severe pain, an erroneous anesthetic solution or direct neuronal injury had been excluded because of rapid and complete recovery after anesthesia. Two weeks later, he was scheduled for TUR-P. He again complained of severe lightning pain after the successful spinal anesthesia with the same anesthetic solution. Because the pain was not relieved by analgesics, he was then anesthetized with enflurane and N2O in oxygen, and there were no neurological complications after anesthesia. Several cases of severe pain during spinal anesthesia have been reported in patients with tabes dorsalis. Although the patient lacks clear symptoms of neurosyphilis, positive serologic examination for syphilis without any other possible causes suggests altered sensitivity of the spinal cord to anesthetic solutions.     

REOPERATION FOR RECURRENT CORONARY ARTERY DISEASE: RESULTS OF 200 CONSECUTIVE CASES

Background : It is well known that reoperation for recurrent coronary artery disease is more difficult than primary coronary artery bypass grafting. However, it is possible to reduce the morbidity and mortality of reoperation to the same level as the initial procedure with careful surgical technique. Methods : A retrospective study of the first 200 patients who underwent redo coronary bypass grafting was undertaken. Results : In the first 200 cases of redo coronary bypass grafting at St George Hospital, Sydney (August 1986–January 1995), there were five in-hospital deaths (2.5%). There was one case of sternal infection (0.5%), which required surgical debridement, three cases of stroke (1.5%), one case of postoperative bleeding (0.5%), which required a return to theatre and six cases (3%) required mechanical ventilation for more than 24h. The need for major postoperative support (such as intra-aortic balloon pumping/adrenaline infusion) was significantly affected by the degree of urgency and the degree of pre-operative ventricular impairment. Conclusions : The mortality rate of redo coronary artery bypass grafting in this series is similar to that of primary surgery described in other reports.     

Effects of vancomycin and ofloxacin on rabbit ERG in vivo

The retinal toxicity of vancomycin and ofloxacin was studied by electroretinogram (ERG) before and after intravitreal injection in rabbits. Vancomycin is known to be effective on methicillin-resistant Staphylococcus aureus. A dose of 1mg vancomycin caused no ERG change for at least eight weeks after injection. The feature that ERG became non-recordable during one to four weeks after an intravitreal injection of 10mg vancomycin, with recovery of only the c-wave was conspicuous. A dose of 200 micrograms ofloxacin did not cause deterioration of the b-wave, the c-wave or the oscillatory potentials throughout the follow-up period up to eight weeks. Judging from the susceptibility of each ERG component to antimicrobials and taking into account the difference of vitreous volume between rabbits and humans, clinical doses of intravitreal single-shot injection should be less than 1mg for vancomycin and 200 micrograms for ofloxacin.     

Detailed Analysis of Mucosal Restoration of the Small Intestine After the Cavitary Two-Layer Cold Storage Method

Small bowel transplantation (SBT) is associated with a high incidence of infectious complications because of ischemia/reperfusion (I/R) mucosal injury concomitant with potent immunosuppression. In this study, we evaluated whether the cavitary two-layer method (cTLM) could reduce I/R injury and allow early mucosal restoration, particularly after prolonged preservation and transplantation. Canine heterotopic segmental SBT was performed immediately without preservation (group 1), after 24-h preservation in UW solution (group 2) or by the cTLM (group 3). The graft samples were taken 1 h after reperfusion and on days 1, 4 and 7. We assessed graft mucosa with detailed microscopic and electromicroscopic analyses. In Group 3, histological injury and cell apoptosis after transplantation were significantly alleviated and rapidly recovered to a similar level of group 1. The mucosal restoration was morphologically completed within 4 days. In contrast, in group 2, more pronounced mucosal injury and delayed recovery were noted. Crypt cell proliferation activity was well maintained in groups 1 and 3 throughout the experimental period. Our ultrastructural analysis suggested that mitochondrial integrity achieved by the cTLM was a basal mechanism under the prompt mucosal restoration. The cTLM could reduce I/R injury, facilitate mucosal regeneration and restore the nearly normal structure early after SBT.