Quality of life after acoustic neuroma surgery

Objective: To assess how surgery affected the quality of life of patients with acoustic neuromas and to investigate possible predictors of the functional outcome following surgery. Study Design: A questionnaire based on the Glasgow Benefit Inventory was completed by patients randomly selected following acoustic neuroma surgery. Setting: Skull base surgery unit of a university teaching hospital (tertiary referral center). Patients: Fifty-three patients with acoustic tumors (follow-up, 1 to 3 y). Results: With regard to overall quality of life, nine patients (17.4%) reported that it became better, 28 patients (53.8%) worse, and 15 patients (28.8%) that it remained the same. Four patients (7.8%) became better off financially, 15 patients (29.4%) worse, and 32 (62.8%) remained unchanged. Forty-one patients (78.8%) did not change their occupation, and 11 (21.2%) had to change their occupation, mainly because of the adverse effects of the operation. With regard to the age at operation, older patients were found to have better overall quality of life. Moreover, younger patients had worse postoperative financial status and they were more likely to change their occupation after the operation. The tumor size did not significantly affect the overall postoperative quality, but it did affect the postoperative financial status (patients with larger tumors were more likely to have worse postoperative financial status). Conclusion: Acoustic neuroma surgery has a significant impact on patients' overall quality of life. Surgeons proposing to operate on small tumors should not assume that the impact on patients' life will be necessarily less than that following the removal of larger tumors. All patients, especially in the younger age group, should be prepared and thoroughly informed about the consequences of the operation on their quality of life.     

Effects on Behaviour and EEG of Single Chain Phospholipases A2 from Snake and Bee Venoms Injected into Rat Brain: Search for a Functional Antagonism

Abstract: Three phospholipase A₂ (PLA₂s), OS₁ and OS₁ purified from the taipan snake venom Oxyuranus scutellatus scutellatus and bee venom PLA₂ were injected to rats by the intracerebroventricular route. OS₁ showed no sign of neurotoxicity at doses at which OS₂ and bee venom PLA₂ produced multiform dose-dependent behavioural effects including motor disturbances (stereotyped movements), compulsive scratching, convulsions and breathing difficulties. EEG recordings showed at the very time when the animal was motionless the induction of several episodes of a low frequency hippocampal theta rhythm, index of long-term changes in synaptic neuroplasticity. Spike-wave discharges were also produced but the occurrence was not systematic. These seizures were often accompanied with behavioural convulsions. Blockers of NMDA receptors and drugs modifying the GABAergic transmission could not abolish the neurotoxic effects of PLA₂s except for diazepam (10 mg/kg intraperitoneally) that prevented only OS₂-induced disturbances. Blockers of L-type Ca²⁺ channels and K⁺ channel openers were also without effect. The toxicity of OS₂ and bee venom PLA₂ is probably due to their initial specific binding to their neuronal receptor sites.     

The heparin-induced thrombocytopenia and thrombosis syndrome: Treatment with intraarterial urokinase and systemic platelet aggregation inhibitors

We report a case of the heparin-induced thrombocy-topenia and thrombosis syndrome presenting with acute ischemia of a lower limb. The patient was successfully treated by withdrawal of heparin products, intraarterial urokinase, and platelet anti-aggregation therapy consisting of Dextran and aspirin.     

Relative effect of surgery and radiotherapy on the internal jugular vein following functional neck dissection

We examined the internal jugular veins in three groups of patients who had undergone (1) a functional neck dissection and radiotherapy, (2) a functional neck dissection alone, or (3) radiotherapy alone, using a noninvasive color Doppler ultrasound scan. The internal jugular veins were ultrasonically bilaterally normal in 18% of patients who had undergone a functional neck dissection and radiotherapy, in 88% of patients who had undergone a functional neck dissection alone, and in 57% of patients who had undergone radiotherapy alone. The combination of a functional neck dissection and radiotherapy significantly affected the internal jugular vein when compared with a functional neck dissection alone.     

Selective inhibition of MAO-A,not MAO-B,results in antidepressant-like effects on DRL 72-s behavior

The effects of monoamine oxidase inhibitors (MAOIs) that selectively inhibit the MAO-A or MAO-B forms of MAO were studied in rats performing under a differential-reinforcement-of-low-rate 72-s (DRL 72-s) schedule of reinforcement. Clorgyline and CGP11305A, irreversible and reversible MAO-A inhibitors, respectively, increased the reinforcement rate, decreased the response rate, and enhanced temporal discrimination. The irreversible MAO-B inhibitor (–)-deprenyl did not produce similar effects. Pargyline did not increase the reinforcement rate at low doses that selectively inhibit MAO-B, but did increase the reinforcement rate at doses that inhibit MAO-A by more than 90%. The present results are in accord with clinical data demonstrating that MAO-A inhibitors are effective therapeutic agents in treating depression while MAO-B inhibitors are of questionable antidepressant efficacy. The present findings provide further evidence that the DRL 72-s schedule may be useful both as a screen for identifying new antidepressants and for investigating the neurochemical effects of antidepressant drugs that are responsible for their therapeutic effects.     

The Relationship of pK a and Acute Skin Irritation in Man

The relationship between pK _a and skin irritation in man is studied for a homologous series of benzoic acid derivatives, which permeate through human skin at comparable rates (15–88 µg/cm²/hr). Skin irritation and pK _a are correlated for pK _a 4. Laser Doppler velocimetric assessment of skin blood flow, color meter readings, erythema, edema, and the primary irritation index are all linearly correlated and related to pK _a, erythema at 24 hr appears to be the most sensitive parameter to variation in pK _a when pK _a 4.     

Superior mesenteric artery is more important than inferior mesenteric artery in maintaining colonic mucosal perfusion and integrity in rats

Mucosal hemodynamics (by reflectance spectrophotometry) and mucosal damage (by histologic examination) following acute colonic ischemia were evaluated in different anatomic locations in the colon of anesthetized rats. The reflectance spectrophotometer provides an index of mucosal hemoglobin concentration (IHB) and an index of oxygen saturation of hemoglobin (ISO₂). The patterns of ischemia without congestion (IHB, ISO₂) during superior mesenteric artery occlusion, and ischemia with congestion (IHB, ISO₂) during portal vein occlusion, previously demonstrated in the stomach and duodenum, are also applicable to the colon. The significant linear correlations between changes (as percent of baseline) in IHB, ISO₂, and hydrogen gas clearance suggest that changes in these indices are adequate indicators of changes in colonic mucosal perfusion. Superior mesenteric artery ligation produced significant reductions in both indices, and an increase in damage in the mucosa of the cecum, transverse colon, splenic flexure, and left colon, but not the rectum. Inferior mesenteric artery ligation produced only slight reduction in these indices and minimal damage only in the mucosa of the splenic flexure. These results support the hypothesis that the superior mesenteric artery is more important than the inferior mesenteric artery in maintaining colonic perfusion and colonic mucosal integrity in the rat.Supported by the American Society for Gastrointestinal Endoscopy Career Development Award (H850208, H870212), Veterans Administration Medical Research Funds; and in part by research grants (0162-01, 0162-02; 0291-01) from the Smokeless Tobacco Research Council, Inc.; and by funds provided by the Cigarette and Tobacco Surtax Fund of the State of California through the Tobacco Related Disease Research Program of the University of California.     

The role of specific DNA adducts in the induction of micronuclei by N-hydroxy-2-acetylaminofluorene in rat liver in vivo

N-Hydroxy-Z-acetylaminofluorene (N-OH-AAF) was administeredi.p. to male Wistar rats 17 h after partial hepatectomy. Hepatocyteswere analyzed for the presence of micronuclei 7 h, 1, 2, 3 and4 days after injection. N-OH-AAF treatment resulted in a highfrequency of micronucleated hepatocytes at days 3 and 4 (19.5and 19.6 respectively). The frequency of micronucleated hepatocyteswas not increased above control values when hepatocytes wereisolated as early as 7 h, 1 or 2 days after injection. Pretreatmentwith the sulfotransferase inhibitor pentachlorophenol (PCP)45 min before injection of N-OH-AAF almost completely preventedthe formation of micronuclei by N-OH-AAF. Parallel biochemicalstudies indicated that inhibition of sulfation of N-OH-AAF byPCP pretreatment prevented the formation of the N-acetylatedDNA adducts iV-deoxyguanosin-8-yl-AAF and 3-deoxyguanosin-N²-yl-AAFby {small tilde}85%. Total adduct formation to DNA was, however,not lowered because of an increase in the formation of the deacetylatedadduct, N-deoxy-guanosin-8-yl-AAF. The lower frequency of micronucleatedhepatocytes observed in the group pretreated with PCP, did notresult from less proliferative activity in this group as comparedto the group treated with N-OH-AAF alone. Therefore, the decreasein the formation of micronuclei indicates that PCP preventsthe clastogenic damage caused by N-OH-AAF. It is concluded thatthe clastogenicity of N-OH-AAF in rat liver is related to theformation of N-acetylated DNA adducts (i.e. N-deoxyguanosin-8-yl-AAFand/or 3-deoxy-guanosin-N²-yl-AAF) and is not related to theformation of the deacetylated DNA adduct N-deoxyguanosin-8-yl-AF.     

Generation and comparative analysis of approximately 3.3 Mb of mouse genomic sequence orthologous to the region of human chromosome 7q11.23 implicated in Williams syndrome.

Williams syndrome is a complex developmental disorder that results from the heterozygous deletion of a approximately 1.6-Mb segment of human chromosome 7q11.23. These deletions are mediated by large (approximately 300 kb) duplicated blocks of DNA of near-identical sequence. Previously, we showed that the orthologous region of the mouse genome is devoid of such duplicated segments. Here, we extend our studies to include the generation of approximately 3.3 Mb of genomic sequence from the mouse Williams syndrome region, of which just over 1.4 Mb is finished to high accuracy. Comparative analyses of the mouse and human sequences within and immediately flanking the interval commonly deleted in Williams syndrome have facilitated the identification of nine previously unreported genes, provided detailed sequence-based information regarding 30 genes residing in the region, and revealed a number of potentially interesting conserved noncoding sequences. Finally, to facilitate comparative sequence analysis, we implemented several enhancements to the program, including the addition of links from annotated features within a generated percent-identity plot to specific records in public databases. Taken together, the results reported here provide an important comparative sequence resource that should catalyze additional studies of Williams syndrome, including those that aim to characterize genes within the commonly deleted interval and to develop mouse models of the disorder.