Acute effects of the novel antidepressant venlafaxine on cognitive event-related potentials (P300), eye blink rate and mood in young healthy subjects.

Venlafaxine is a novel non-tricyclic antidepressant, which preclinically has demonstrated serotonin, norepinephrine, and dopamine reuptake inhibiting effects. In this study acute effects of single oral doses of placebo, 12.5 mg, 25 mg, and 50 mg venlafaxine on event-related potentials (ERPs), eye blink rate and mood were studied in 16 healthy subjects. ERPs were investigated in an auditory odd-ball paradigm before as well as 3 h after each drug intake. In addition to 17 EEG leads, vertical and horizontal EOGs were recorded. After EOG minimization and visual artefact rejection the peak latencies of the spatial average were determined by an automatic procedure. The applied methods of data acquisition, artefact processing, objective component determination and statistical analysis were successful in describing acute effects of venlafaxine on ERPs in normals. N1 and P2 latencies were not affected. An increase in P2 amplitude in the relevant central and frontal regions was seen, reflecting some effect on automatic information processing. Stimulus evaluation time was not affected, as P300 latency remained unchanged. P300 amplitude was not affected at the relevant central and parietal region. Blink rate was not changed. By means of the adjective checklist a dose-dependent decrease of "extroversion" and "high spirits" and an increase of "introversion" was observed. Our findings suggest that venlafaxine affects human information processing less than would be expected from the more centrally inhibiting classical antidepressants.

Use of the fascia sheath coverage and exogenous fibrin clot in the treatment of complex meniscal tears.

In a previous series, complex meniscal tears, including double flap, double longitudinal, and radial tears, there was reported a high failure rate (14 of 58 repairs, 24%) when treated by conventional arthroscopic repair techniques. There was only one tear in the anterior middle one-third of the lateral meniscus in this group. The use of a fascia sheath to cover the repaired area improves healing rates an additional 17% (from 75% to 92%) with these tear classifications, with the exception of radial split tears in the middle one-third of the lateral meniscus. The present repair technique includes rasp abrasion of the parameniscal synovium, peripheral white rim, and tear surface of the handle fragment. The meniscus is sutured with fully diverged sutures. A rectangle of fascia from the distal anterolateral thigh, trimmed to 25 x 35 to 40 mm, is prepared with the double-armed meniscus suture run along opposite sides. One or two "hold-down" sutures are tied to the superior and inferior main sutures. The four hold-down sutures from the corners and the previously placed hold-down sutures are pulled through the capsule with previously placed pull-through sutures to pull the fascia over the meniscal repair. The exogenous blood clot is injected in the tear under the sheath. This preliminary report suggests that improved healing rates can be obtained with most complex tears by meticulous meniscal repair followed by coverage with the fascia sheath and then exogenous clot injection. Repairs of tears in the middle one-third of the lateral meniscus still show a high failure rate.

Cognitive psychophysiology in nootropic drug research: effects of Ginkgo biloba on event-related potentials (P300) in age-associated memory impairment.

Extracts from the leaves of Ginkgo biloba have been suggested to be useful in the treatment of various symptoms of impaired brain functions in advanced age. To elucidate specific mechanisms of the possible clinical benefit, the effects of Ginkgo biloba extract Ginkobene on cognitive information-processing were investigated by means of long-latency auditory event-related potentials. In a double-blind placebo-controlled study, 48 patients (29 women and 19 men) aged between 51 and 79 years with the diagnosis of age-associated memory impairment had 57 days' treatment with a daily dosage of 3 x 40 mg Ginkobene or placebo. To evaluate acute, chronic, and superimposed drug effects, psychophysiological investigations were carried out on day 1 and day 57 before and 3 hours after drug administration. ERP investigations were carried out by means of a two-tone auditory oddball paradigm. In addition to 17 EEG leads, vertical and horizontal EOGs were recorded. After minimizing ocular artifacts and visual artifact rejection, latencies and topographic distributions of N1 and P2 components (non-targets) and N2 and P300 components (targets) were calculated by an automatic procedure. When compared to the placebo group, in the Ginkobene group no consistent and unequivocal changes on N1, P2, N2, and P300 amplitudes or on N1, P2, and N2 latencies were observed. P300 latency was shortened by 31 ms, 38 ms, and 32 ms in the Ginkgo biloba group after acute, chronic, and superimposed drug administration. It may therefore be hypothesized that the decrease of P300 latency in the Ginkgo biloba group may reflect shorter stimulus-evaluation time.(ABSTRACT TRUNCATED AT 250 WORDS)

Arthroscopic meniscal repair using an exogenous fibrin clot.

In this series of 153 meniscus tears, 8% were isolated whereas 92% were in conjunction with anterior cruciate ligament (ACL) tears. Exogenous fibrin clot was injected with a blunt needle in the seam of the tear. One to 2 ml of clot was sufficient to fill an average defect. When gaps could not be closed, such as with a radial split or flap in the posterior one-third of the meniscus, a fascia sheath was used to cover these defects and the exogenous clot was injected under the cover of the sheath. ACL-deficient knees were stabilized with an intraarticular reconstruction. Overall results were 64% healed, 24% incompletely healed, and 12% failed (less than 50% of vertical height of tear healed). In ACL-associated knees, the failure rate was 1.5% for tears in which surgery occurred up to two months after the time of injury. The failure rate for tears surgically treated two months to several years after injury was 20%. Complex tears had an even higher failure rate of 22%. It is these tears that will be treated with the fascia sheath. The isolated tear failure rate was 41% without the exogenous fibrin clot versus 8% with the exogenous clot. Complications included retear and popliteal neurovascular injury. Repair of almost all menisci in young active athletes is possible using the transarticular arthroscopic technique with a posterior incision. Repairs of tears of less than two months' duration from the time of injury to surgery result in significantly higher healing rates than those of more chronic tears. Isolated repairs heal significantly better with exogenous fibrin clot injection.