Expression of rabbit Ig allotypes in litters of mothers immunized against a paternal allotype.

Sera of successive littermates of mothers producing anti-allotype antibodies (Ab) were analysed for altered a locus or b locus allotype expression. We measured the allotype concentration in sera of 66 individuals (17 litters) of seven mothers producing anti-a1 Ab, and 63 individuals (15 litters) of seven mothers producing anti-b4 Ab, in an enzyme-linked immunosorbent assay (ELISA). We confirmed that the ability to induce allotype suppression in utero increases with the number of antigen boosts applied to the mother, even though the Ab titre in the maternal serum may be decreased. All individuals of a litter expressed the allotype in about equal concentration. This contrasts the results we obtained when newborn rabbits were injected with anti-allotype antiserum. Injection of the same amount of anti-allotype antiserum into nine offspring of two mothers caused allotype suppression in only five individuals, showing no effect in the others. No suppression was observed when IgG-depleted antiserum was injected into newborn rabbits. As expected, maternal antibodies to a paternal allotype do not affect the Mendelian distribution of the progeny phenotypes.     

Primary Hemiarthroplasty for Proximal Humeral Fractures in the Elderly: Long-Term Functional Outcome and Social Implications

Abstract Background: Primary shoulder hemiarthroplasty is an established treatment modality for complex fractures of the proximal humerus. Long-term functional outcome is often disappointing. However, little is known about social implications particularly in the elderly. Methods: A single-institution case series of consecutive geriatric patients (age > 70 years) treated with shoulder hemiarthroplasty for complex fractures of the proximal humerus between 1994 and 1997 was analysed. Postoperative morbidity, long-term function, radiological outcome and social implications were evaluated. Results: Seventy-seven patients fulfilled the study criteria. Median age at the time of operation was 80 years (range 70–93 years). Systemic and local postoperative complications were observed in 8% including 2 patients (3%) with revision surgery. Postoperative mortality was 1%. Forty-eight patients (62%) were available for follow-up (median 49 months, range 25–80 months), 22 (29%) died from causes unrelated to hemiarthroplasty before follow-up and 7 patients (9%) did not attend follow-up examination. Median Constant-Murley score was 41 points (range 17–77 points). Long-term results concerning pain were satisfying. The Oxford shoulder score ranged from 14 to 40 (median 30). Forty-one patients (85%) still lived in their original environment and managed their daily life independently despite poor shoulder function. Four patients (8%) lived in a retirement home and 3 (6%) in a nursery home. Eighty percent of our patients were still able to use public transportation, do the daily shopping and wash their whole body by themselves. Conclusion: Most patients managed their daily life independently despite poor shoulder function.     

Force recruitment during electrical nerve stimulation with multipolar intrafascicular electrodes

Experimentally, during electrical nerve stimulation, the influence is examined of two intrafascicular anodes on the force recruitment with one intrafascicular cathode. It is found that the anodes suppress recruitment and that this effect is more pronounced when the distance of the anodes to the cathode is decreased, or when the anodal currents are increased. The measured recruitment curve patterns can be qualitatively explained by a nerve stimulation model that calculates theoretical recruitment curves for intrafascicular multi-electrode configurations. Discrepancies between the experimental and the theoretical recruitment curves are seen, but these can be understood by taking into account a non-uniform fibre distribution.     

RA-spezifische Autoantikörper gegen ein 68k-Antigen

Zusammenfassung Die Diagnostik vieler rheumatischer Systemerkrankungen wird heute durch den Nachweis von Autoantik?rpern unterstützt und erleichtert. Für die Serodiagnostik der Rheumatoiden Arthritis (RA) stehen nur die doch wenig spezifischen Rheumafaktoren zur Verfügung. Mit dem Ziel, neue krankheitsspezifische Autoantik?rper nachzuweisen, erfolgte eine besondere Proteinaufarbeitung aus Synovialisbiopsien und anderen Geweben. Western Blots der gewonnenen Proteine wurden eingesetzt, um Seren von RA-Patienten und solchen mit anderen rheumatischen Erkrankungen zu untersuchen. Die signifikanteste Immunreaktion von RA-Patienten richtete sich gegen ein 68k-Antigen, welches vermutlich ubiquit?r exprimiert wird, da es nicht nur in Synovialis, sondern in allen weiteren untersuchten Humangeweben und HeLa-Zellen nachgewiesen werden konnte. Der isoelektrische Punkt liegt bei 5,1, das Protein ist O-glykosyliert und im endoplasmatischen Retikulum und/oder Cytoplasma lokalisiert. Antik?rper gegen dieses 68k-Antigen waren bei 110 von 167 RA-Patienten nachzuweisen, was einer Sensitivit?t von 66% entspricht. Ihr Vorkommen war unabh?ngig vom Rheumafaktornachweis, da sie auch bei 7 von 12 seronegativen RA-Patienten zu finden waren, dagegen nur bei einem Patienten aus einer Kontrollgruppe von 98 Patienten mit anderen rheumatologischen Krankheitsbildern, bei einem von 22 HIV-Patienten und überhaupt nicht bei 55 Gesunden. Daraus resultiert eine RA-Spezifit?t für diesen Antik?rper von 99%. Wegen der auff?lligen Krankheitsspezifit?t der anti-68k-Antik?rper liegt es nahe, nach korrespondierenden autoreaktiven T-Zellen zu suchen, um die Rolle dieser neuen Autoreaktivit?t in dem Pathomechanismus der RA zu analysieren. Eingegangen: 20. Mai 1996 Akzeptiert: 13. Februar 1997     

Composite aortic root replacement in acute type A dissection: time to rethink the indications?

OBJECTIVE: The indications for aortic root replacement in acute type A dissection are unclear. We reviewed the immediate and long-term outcome of consecutive patients in a series in which a low-threshold policy of composite aortic root replacement had evolved. METHODS: From a prospectively compiled aortic surgery database, we identified 162 patients who had either supracoronary interposition grafting, Group A (n=89), or composite root replacement, Group B (n=73) for acute type A dissection. Patients receiving total arch replacements were excluded. Operative and clinical details were analyzed and patient survival was compared to an age and gender matched census cohort. Need for reoperation on the proximal or distal aorta was also noted. Follow-up totaled 795.5 patient-years. RESULTS: Hospital mortality rates were identical in both groups (12.3%: 11 deaths in group A; 9 in group B). Chronic pulmonary disease, diabetes, malperfusion, hemodynamic compromise and aortic root dilatation were independent risk factors for hospital death. Actuarial survival estimates at 1, 5 and 10 years were 79% (71-88%), 64% (53-75%), and 55% (41-68%) for group A, and 79% (70-86%), 73% (62-83%), and 65% (52-78%) for group B (P=0.48). Age and operative patency of the ascending false lumen were independent risk factors for death after hospital discharge. Proximal aortic reoperation was required for four patients in group A and none in group B (P=0.085). CONCLUSION: A strategy of replacement rather than repair of the dissected aortic root for specific indications in type A dissection yielded high survival and low proximal reoperation rates. These results support an aggressive policy of composite root replacement in acute type A dissection.