Histology of the bone-implant interface 45 years after bilateral implantation of a Judet acrylic hip prosthesis: a case report.

The Judet acrylic femoral head hemiprosthesis was first implanted in 1946. We performed bilateral revision in one patient 45 years after implantation of a Judet prosthesis. Histological analysis of femoral neck remnants and joint capsule did not show aggressive osteoclastic bone resorption or signs of dynamic bone apposition as is frequently observed nowadays with failed total hip prostheses.

Conditioning-specific reflex modification of the rabbit (Oryctolagus cuniculus) nictitating membrane response: generality and nature of the phenomenon.

Conditioning-specific reflex modification (CRM) occurs when classical conditioning modifies responding to an unconditioned stimulus in the absence of a conditioned stimulus. This form of reflex modification suggests that learning modifies the unconditioned reflex pathway. Rabbit (Oryctolagus cuniculus) nictitating membrane responses to 5 intensities and 3 durations of airpuff (AP) or periorbital electrical stimulation (ES) were monitored before and after conditioning.

Time-dependent mechanical properties of HA/TCP particles in relation to morsellized bone grafts for use in impaction grafting.

In reconstructive surgery human bone defects are sometimes filled with the use of the impaction bone grafting technique. Currently different types of biomaterial particles are being developed as bone-substitute materials. Before these biomaterials can be applied their mechanical and biological behavior should be characterized.

Acetabular revision with impacted freeze-dried cancellous bone chips and a cemented cup: a report of 7 cases at 5 to 9 years' follow-up.

The long-term results of bone impaction grafting with fresh-frozen femoral head allografts and a cemented cup are favorable. Because of intermittent shortage of fresh-frozen femoral heads at our local bone bank, we used processed freeze-dried bone in 7 acetabular revisions operated between 1989 and 1994. All 7 consecutive patients were followed annually.

Favorable results of acetabular reconstruction with impacted morsellized bone grafts in patients younger than 50 years: a 10- to 18-year follow-up study of 34 cemented total hip arthroplasties.

We report a long-term review of 41 acetabular reconstructions using impacted morsellized bone grafts and a cemented total hip arthroplasty (THA) in patients younger than 50 (22-49; average 38) years. Reconstruction was performed in 23 primary THA (19 patients) and 18 revision THA (17 patients). 3 patients were lost to follow-up and 3 (4 hips) died within 10 years of surgery; none had a revision.

Gene expression profiles during long-term memory consolidation.

Changes in gene expression have been postulated to occur during long-term memory (LTM). We used high-density cDNA microarrays to assess changes in gene expression 24 h after rabbit eye blink conditioning. Paired animals were presented with a 400 ms, 1000 Hz, 82 dB tone conditioned stimulus that coterminated with a 100 ms, 60 Hz, 2 mA electrical pulse unconditioned stimulus.

Interactions of prefrontal cortex during eyeblink conditioning as a function of age.

Changes in regional cerebral blood flow (rCBF) in eleven elderly subjects during pairings of tone and air puff were compared to rCBF changes during pairings in young subjects. Although all subjects reported being aware of the relationship between tone and air puff, elderly subjects did not condition as well as young subjects and their rCBF measures were attenuated. Covarying the performance differences between young and old subjects did not change this conclusion suggesting that differences in neural activation during learning are related to binding of CS-US information prior to the impact of the association on performance.

Acetabular reconstruction with impacted morcellized cancellous bone autograft and cemented primary total hip arthroplasty: a 10- to 17-year follow-up study.

During the period 1979 through 1986, 69 acetabular reconstructions in 63 patients were performed with the use of autologous morcellized bone-grafts because of acetabular bone stock loss. Nine cases (10 hips) were lost to follow-up. Eleven patients (12 hips) died <10 years after surgery; none had a revision.

Impacted morsellized bone grafting and cemented primary total hip arthroplasty for acetabular protrusion in patients with rheumatoid arthritis: an 8- to 18-year follow-up study of 36 hips.

Between 1979 and 1989, we performed 36 primary total hip replacements in 31 rheumatoid arthritis patients with protrusio acetabuli. The deficient acetabulum was reconstructed with autologous morsellized bone grafts from the femoral head. 3 patients were lost to follow-up.

Conditioning the unconditioned response: modification of the rabbit's (Oryctolagus cuniculus) unconditioned nictitating membrane response.

Conditioning-specific reflex modification (CRM) occurs when classical conditioning modifies responding to an unconditioned stimulus (US) in the absence of a conditioned stimulus (CS). Three experiments monitored rabbit nictitating (Oryctolagus cuniculus) membrane unconditioned responses to 5 intensities and 4 durations of periorbital electrical stimulation before and after CS or US manipulation. CRM occurred after 12 days of CS-US pairings but not following unpaired CS/US presentations or restraint.

Kinetic and frequency-domain properties of reflex and conditioned eyelid responses in the rabbit.

Eyelid position and the electromyographic activity of the orbicularis oculi muscle were recorded unilaterally in rabbits during reflex and conditioned blinks. Air-puff-evoked blinks consisted of a fast downward phase followed sometimes by successive downward sags. The reopening phase had a much longer duration and slower peak velocity.

Mechanical characteristics of impacted morsellised bone grafts used in revision of total hip arthroplasty.

The use of impacted, morsellised bone grafts has become popular in revision total hip arthroplasty (THA). The initial stability of the reconstruction and the effectiveness of any subsequent process of revitalisation and incorporation will depend on the mechanical integrity of the graft. Our aim in this study was to document the time-dependent mechanical properties of the morsellised graft.

Role of growth factors in the incorporation of unloaded bone allografts in the goat.

Revision of a failed total joint replacement often demands bone grafting methods to restore deficient bone stock. However, impaired allograft incorporation can be the result of inadequate host or graft properties. The stimulation of bone healing with growth factors could provide a new approach to deal with this problem.

Indomethacin for 3 days is not effective as prophylaxis for heterotopic ossification after primary total hip arthroplasty.

Although indomethacin is effective in preventing heterotopic ossification (HO) after total hip arthroplasty (THA) when used for 8 to 14 days, side effects are frequently observed. We conducted a prospective, nonrandomized pilot study of prophylaxis for HO in THA using indomethacin for 3 days. We used a 2-stage design for phase 2 clinical data, based on earlier studies in our department.

The effects of scopolamine on changes in regional cerebral blood flow during classical conditioning of the human eyeblink response.

We examined the effects of scopolamine on the functional anatomy of classical conditioning of the human eyeblink response. Ten healthy young normal female volunteers (mean age +/- SEM: 26.7 +/- 0.

Classical conditioning increases membrane-bound protein kinase C in rabbit cerebellum.

We examined membrane-bound protein kinase C (PKC) in the cerebellum of rabbits given paired presentations of a tone conditioned stimulus (CS) that co-terminated with a periocular electrical stimulation unconditioned stimulus (US) or unpaired presentations of the CS and US or restraint in the experimental context. PKC activation was measured by quantitative film autoradiography of [3H]phorbol 12,13-dibutyrate ([3H]PBt2) binding in the molecular and granule cells layers of lobule HVI, anterior vermis and Crus I, and in the dentate/interpositus nuclei. There was a statistically significant increase in [3H]PBt2 binding within the molecular layer of lobule HVI in rabbits given paired training relative to controls.

Pairing-specific long-term depression prevented by blockade of PKC or intracellular Ca2+.

Long-term depression was established in cerebellar Purkinje cells using 20 pairings of a brief, high frequency train of parallel fiber stimulation with a subsequent 100 ms depolarizing current injection. Effects were assessed on the peak amplitude of Purkinje cell excitatory post synaptic potentials (EPSPs) elicited by single parallel fiber test pulses. Intradendritically recorded Purkinje cell EPSPs exhibited long-term (>20 min) reduction in peak amplitude following paired stimulation but not if pretreated with the protein kinase C inhibitor calphostin C or iontophoretically injected with the calcium chelator EGTA.

Intracellular correlates of acquisition and long-term memory of classical conditioning in Purkinje cell dendrites in slices of rabbit cerebellar lobule HVI.

Intradendritic recordings in Purkinje cells from a defined area in parasaggital slices of cerebellar lobule HVI, obtained after rabbits were given either paired (classical conditioning) or explicitly unpaired (control) presentations of tone and periorbital electrical stimulation, were used to assess the nature and duration of conditioning-specific changes in Purkinje cell dendritic membrane excitability. We found a strong relationship between the level of conditioning and Purkinje cell dendritic membrane excitability after initial acquisition of the conditioned response. Moreover, conditioning-specific increases in Purkinje cell excitability were still present 1 month after classical conditioning.

Acetabular reconstruction with impacted morsellised cancellous bone graft and cement. A 10- to 15-year follow-up of 60 revision arthroplasties.

We report a long-term review of 60 acetabular components revised using impacted, morsellised bone allografts and a cemented polyethylene cup. The acetabular defects were cavitary (37) or combined (23). Follow-up was for a mean 11.

Excisional biopsy of impalpable soft tissue tumors. US-guided preoperative localization in 12 cases.

We present a technique to facilitate excisional biopsy of impalpable soft tissue tumors. A modified Kopans localization needle is positioned preoperatively under ultrasound-guidance (7.5 MHz).