Paraproteins and plasma cell dyscrasias

BACKGROUND: Progressive deterioration and ensuing death following a neurosurgical procedure often represents a diagnostic challenge to the team responsible for patient care. Many, but not all, causes are treatable if a diagnosis is made early. METHODS: A 69-year-old woman who died 6 weeks post-operatively following a meningioma resection is reported. An initial routine post-operative course became complicated by progressive neurological deterioration 3-4 weeks later. Despite extensive investigation she died 6 weeks post-operatively without a diagnosis. RESULTS: Autopsy demonstrated extensive Candida meningitis. A review of the literature demonstrates this to be a reported complication in high risk patients, difficult to diagnose, but treatable when identified. CONCLUSIONS: Fungal meningitis should be high in the differential diagnosis in the post-operative patient with delayed, unexplained neurological deterioration, especially when associated with negative CSF cultures.     

Impact of d-amphetamine on temporal estimation in pigeons tested with a production procedure

The use of pedicled flexor digitorum superficialis tendon as a tendon graft in the second stage of flexor tendon reconstruction has the advantage of employing local intrasynovial tendon graft and allowing early active range of motion. This method of staged flexor tendon reconstruction was used in 47 patients between 1983 and 1993. Thirty-three patients were evaluated 1 year or longer after the second stage of surgery. The follow-up period averaged 3.7 years. Sixty-four percent of the injuries were in zone II, and 30% were Boyes grade V in severity. Good to excellent results were achieved in 64% of patients. Three patients needed graft tenolysis. Postoperative persistent flexion contractures ranging from 8 degrees to 55 degrees of the proximal interphalangeal or distal interphalangeal joints or both were present in 88% of patients. Several factors that influenced the final outcome were identified: age over 25 years, zone II injuries of Boyes grade V, and the lack of a regular postoperative rehabilitation program were associated with relatively less successful final results.     

Effects of caffeine consumption on delayed conception

The authors examined the effects of caffeine consumption on waiting time to conception in the Reproductive Health Study, a retrospective study of 1,430 non-contracepting, parous women interviewed between July 1989 and June 1990 at Fishkill, New York, and Burlington, Vermont. Information was obtained on 2,501 pregnancies since 1980. Women's reported consumption of caffeinated beverages during the first month of pregnancy was used to estimate daily caffeine intake, which was categorized as none, 1-150, 151-300, and > or = 301 mg. Information on delayed conception was analyzed as a dichotomous variable (< or = 12 months delay vs. > 12 months delay), and the per cycle probability of conception (fecundability) was estimated using waiting time to conception as a continuous variable. Odds ratios of delayed conception and fecundability ratios adjusted for age, parity, smoking, last contraceptive used, infertility history, and race, were estimated by logistic regression and Cox proportional hazard models, respectively. Women who did not smoke and who consumed no caffeine were used as a reference group. The adjusted odds ratio of delayed conception for more than one year was not increased among women who consumed < or = 300 mg of caffeine daily. However, the odds ratio (OR) was 2.65 (95% confidence interval (CI) 1.38-5.07) among nonsmokers who consumed > or = 301 mg of caffeine daily. Although smoking per se was associated with a significant increased risk of delayed conception (OR = 1.77, 95% CI 1.33-2.37), no effect of high caffeine consumption was observed among women who smoked. Fecundability was reduced among nonsmokers who consumed more than 300 mg caffeine daily (fecundability ratio = 0.74, 95% CI 0.59-0.92). Smoking reduced the fecundability ratio, but the authors observed no effect of caffeine consumption on fecundability among women who smoked. Other studies provide biologic plausibility for these findings. The authors conclude that high levels of caffeine consumption may result in delayed conception among women who do not smoke cigarettes.     

Repair of ruptured sinus of valsalva aneurysm: determinants of long-term survival

BACKGROUND: Ruptured sinus of Valsalva aneurysm is a rare cardiac anomaly and long-term survival after surgical treatment is not well established. This study was designed to investigate the determinants of long-term survival after repair of ruptured sinus of Valsalva aneurysm. METHODS: From April 1978 to April 1996, 53 patients underwent operation for ruptured sinus of Valsalva aneurysm. The incidence among our cardiac surgical population was 0.56%. Long-term survival was investigated in 46 patients (13 to 65 years) who survived the operation, with 96.2% follow-up completeness (mean+/-standard deviation, 6.5+/-4.9 years; maximum, 17.2 years), by univariate and multivariate analyses. RESULTS: There was no early operative death and no recurrence after the initial repair. Actuarial survival was 83.8%+/-8.4% at 15 years. Reoperation, aneurysm draining into the left ventricle, aortic prosthetic dehiscence, bacterial endocarditis, and aortic cross-clamp time (<70 minutes) were significant factors in long-term survival (p < 0.05). Multivariate analysis revealed that only aortic prosthesis dehiscence was the significant factor influencing late survival (p = 0.0001). CONCLUSIONS: Surgical treatment for ruptured sinus of Valsalva aneurysm is safe and has satisfactory results. Aortic prosthesis dehiscence is the independent determinant for long-term survival. Other factors including bacterial endocarditis, concomitant ventricular septal defect repair, and aortic valve replacement did not independently influence long-term survival.     

Effects of intravenous erythromycin on antroduodenal motility in humans: non-invasive observations with real-time ultrasound

Erythromycin has been shown to act on motilin receptors on gastrointestinal smooth muscle in vitro and to accelerate gastric emptying in normal subjects as well as in patients with diabetic mellitus. To evaluate the motor pattern that accounts for this accelerated emptying, the effects of 12.5 mg/min erythromycin vs. placebo on postprandial motility of the antroduodenum was examined with real-time ultrasound in 15 normal subjects. During 10 minutes of observation, erythromycin significantly increased forward transpyloric flow episode (1.04 +/- 0.19 vs. 0.37 +/- 0.41; p < 0.05), forward transpyloric flow duration (5.79 < 4.49 vs. 3.19 < 1.72 seconds; p < 0.05) and improved antro-pyloro-duodenal coordination (0.43 +/- 0.23 vs. 0.21 +/- 0.17; p < 0.05). However, no significant differences were found for gastric peristaltic cycle (22.62 +/- 3.06 vs. 23.40 +/- 2.14 seconds; p > 0.05), retrograde transpyloric flow episode (0.13 +/- 0.16 vs. 0.18 +/- 0.29; p > 0.05), and retrograde transpyloric flow duration (1.24 +/- 0.30 vs. 1.38 +/- 0.58 seconds; p > 0.05). We conclude that erythromycin increases episode and duration of forward transpyloric flow, and improves antro-pyloro-duodenal coordination, which may play a role in accelerating gastric emptying.     

Coordinated activation of muscle fibres by different conduction velocities in branches of a crustacean motor axon

Higher conduction velocities in branches of the fast excitor axon to distal muscle fibres ensure that these fibres are activated almost simultaneously with proximal fibres in the claw closer muscle of lobsters, producing a contraction of maximal force.