Bilateral cerebellopontine angle tumors in neurofibromatosis type 2

In a series of over 500 cases of cerebellopontine angle tumors, 19 patients had bilateral neurinomas. Four of these tumors arose from the facial rather than the acoustic nerve. A conservative policy regarding surgery had been adopted in an effort to prevent hearing loss for as long as possible. Nevertheless, all patients operated on in this series are now totally deaf. The results of managing these patients surgically and conservatively are discussed.     

Method of single-lung transplantation in the absence of a left atrial cuff.

A method used clinically for anastomosing the pulmonary veins to the left atrium, in the absence of a left atrial cuff, during single-lung transplantation by reconstructing the atrium with pericardium is described. Postoperative ventilation/perfusion scans show normal pulmonary blood flow.     

Optimization of the quinoline and substituted benzyl moieties of a series of phenyltetrazole leukotriene D4 receptor antagonists.

This report describes the development of a series of highly potent quinoline-based leukotriene D4 (LTD4) receptor antagonists containing an N-benzyl-substituted phenyltetrazole moiety. They were designed to provide both the correct positioning of the acidic function and secondary lipophilic domain required for strong receptor binding. Members of this series possess high activity in blocking LTD4-induced contractions of isolated guinea pig ileum. Compound 32, LY287192 (2-[[5-[3-[2-(7-chloroquinolin-2- yl)ethenyl]phenyl]-2H-tetrazol-2-yl]methyl]-5-fluorobenzoic acid sodium salt), blocked contraction with a pKB value of 9.1 +/- 0.3. Qualitative structure-activity studies have demonstrated specific requirements for the best activity. In particular, ortho substitution of the benzyl group with an acidic function was crucial for maximum potency. In cases similar to 32, where the benzyl group possesses an ortho carboxylate, the N-2-substituted tetrazole isomer showed 100-fold greater activity relative to the corresponding N-1 isomer. This pattern was reversed when the acid was substituted at the para position. The quinoline unit may be replaced by other nitrogen-containing heterocycles.     

Synergistic Deposition of C4d by Complement-Activating and Non-activating Antibodies in Cardiac Transplants

The role of non-complement-activating alloantibodies in humoral graft rejection is unclear. We hypothesized that the non-complement-activating alloantibodies synergistically activate complement in combination with complement-activating antibodies. B10.A hearts were transplanted into immunoglobulin knock out (Ig-KO) mice reconstituted with monoclonal antibodies to MHC class I antigens. In allografts of unreconstituted Ig-KO recipients, no C4d was detected. Similarly, reconstitution with IgG1 or low dose IgG2b alloantibodies did not induce C4d deposition. However, mice administered with a low dose of IgG2b combined with IgG1 had heavy linear deposits of C4d on vascular endothelium. C4d deposits correlated with decreased graft survival. To replicate this synergy in vitro, mononuclear cells from B10.A mice were incubated with antibodies to MHC class I antigens followed by incubation in normal mouse serum. Flow cytometry revealed that both IgG2a and IgG2b synergized with IgG1 to deposit C4d. This synergy was significantly decreased in mouse serum deficient in mannose binding lectin (MBL) and in serum deficient in C1q. Reconstitution of MBL-A/C knock out (MBL-KO) serum with C1q-knock out (C1q-KO) serum reestablished the synergistic activity. This suggests a novel role for non-complement-activating alloantibodies and MBL in humoral rejection.     

Predictors of incident depression after hip fracture surgery.

OBJECTIVE: Depression after hip fracture surgery is prevalent and associated with increased mortality rates and impaired functional recovery. The incidence of new-onset depressive symptoms in patients initially not depressed after hip fracture surgery and their relationship with functional recovery is unknown. METHODS: A cohort of 139 nondepressed elderly patients (>60 years) hospitalized for hip fracture surgery were followed up for six months. Clinically significant depressive symptoms were defined as a score of 7 or more on the 15-item Geriatric Depression Scale. RESULTS: The authors found a cumulative incidence rate of 20.5% adjusted for dropouts. Multiple Cox-regression analyses yielded the presence of subthreshold symptoms of depression, anxiety, pain, and cognitive impairment at baseline, the premorbid level of mobility, and a history of (treated) depression as risk factors for incident depression (p <0.05). A forward, conditional procedure identified postoperative pain (hazard ratio [HR] = 1.32, 95% confidence interval [CI]: 1.14-1.53, Wald chi(2) = 13.57, df = 1, p <0.001) and baseline anxiety (HR = 1.25, 95% CI: 1.08-1.44, Wald chi(2) = 8.86, df = 1, p = 0.003) as the strongest independent risk factors. Incident depression was associated with a less favorable outcome at 3 months follow-up. CONCLUSION: This exploratory study identified two treatable baseline characteristics that predicted incident depression in nondepressed patients after hip-fracture surgery.     

A pilot study of medical student 'abuse'. Student perceptions of mistreatment and misconduct in medical school

A pilot survey of one third-year medical school class was carried out to explore student perceptions of mistreatment and professional misconduct in medical school training. Students were asked to rate the frequency and cite sources of mistreatment and misconduct among classmates, faculty, residents, and interns. They were also asked to assess the effects of such episodes on their physical health, emotional well-being, social and family life, and attitudes toward becoming a physician. The results indicate that students perceive mistreatment (particularly verbal abuse and unfair tactics) to be pervasive and professional misconduct all too common. As many as three fourths of the students report having become more cynical about academic life and the medical profession as a result of these episodes. Two thirds feel they are worse off than their peers in other professions. More than a third have considered dropping out of medical school and one fourth report they would have chosen a different profession had they known in advance about the extent of mistreatment they would experience. Rather than dismiss these problems as isolated events, we need to examine this issue more closely.     

The effects of povidone-iodine preparation on the incidence of post-tympanostomy otorrhea

Persistent otorrhea after tympanostomy tube placement in children is a common complication. Previous reports have suggested that bacteria present within the ear canal may be the cause of postoperative drainage. Preparation of the ear canal with povidone-iodine solutions has been recommended to decrease these infections. A prospective study evaluating the efficacy of povidone-iodine ear canal preparation before myringotomy and tube placement was performed in 111 children (220 ears) with documented chronic otitis media with effusion. One ear in each patient was prepared with povidone-iodine. The contralateral ear in each child was used as control. Postoperative otorrhea developed in seven (6.3%) of the treated ears within 14 days, compared to eleven (10%) of the ears in the control group. The difference was not statistically significant (p greater than 0.05). Purulent or mucoid middle ear effusions and edematous or granular middle ear mucosa were associated with a significantly higher incidence of postoperative otorrhea (p less than 0.05). This study suggests that postoperative otorrhea is generally a consequence of preoperative middle ear condition rather than contamination from the external canal. Antimicrobial therapy should be considered when purulent effusion or granulation tissue is seen.     

Implantation response following clinical heart-lung transplantation

Implantation response has been a critical problem following heart-lung and lung transplantation. While the precise etiology of this problem remains unclear, improvements in organ preservation would be expected to have a beneficial effect on implantation response. The time-related profile of the implantation response was studied in 20 patients who underwent heart-lung transplantation between March 1984-March 1987. In 10 operations the donors had intravenous prostaglandin E-1 pretreatment while 10 had no vasodilatation before explantation of the organs. Otherwise lung preservation and early (2 weeks) immunotherapy were similar in both groups. The implantation response was evaluated by chest films and postoperative lung functions and mechanics. Roentgenographic implantation response was evident from the first postoperative day, was less evident at the seventh postoperative day and then gradually increased during the second postoperative week. There was a tendency towards less implantation response in the PGE-1 group than in the control group, but no statistical difference was observed. Patients with severe operative bleeding problems were excluded from the study. Only peak inspiratory pressures were significantly higher in the control group than in the PGE-1 group (p less than 0.01). Other lung function studies (alveolar-capillary pO2 difference, extubation time) were not different in the groups. This study supported the hypothesis that prostaglandin E-1 may have salutary effects on graft preservation and implantation response in heart-lung transplantation. Since 1986, we have performed 16 heart-lung transplantations using graft preservation with PGE-1 and flush perfusion. Thirty-day mortality is 0% and 13 of 16 patients are surviving.