One-way positive cellular reactions between two HLA-A, B, C, D/DR genotypically identical brothers following active allogeneic immunization

The HLA-D/DR region in man encodes major determinants which stimulate T lymphocytes to proliferation. The genetic organization of this region is apparently complex and is at present largely unknown. One obstacle is the scarcity and quality of available typing reagents. In an attempt to obtain high quality anti-DR sera, a series of active immunizations was performed between highly selected, healthy unrelated donors and recipients.
One recipient (AR8) was immunized using cells incompatible for HLA-A2, B40 (w60), Cw3 and DIDRw6 and readily developed anti-A2 and B40 antibodies but no anti-C, DR, or other antibodies. When tested against his HLA genotypically fully identical brother using the cellular MLC, PLT, or CML techniques before immunization, results were mutually negative as expected. Following immunization, however, AR8 was able to mount MLC, PLT, and possibly CML responses against lymphocytes from the brother while the reverse combinations remained negative. When tested in the family the trait(s) thus identified seems to be maternally inherited.
These results suggest the existence of minor histocompatibility determinants encoded from regions not closely linked to HLA. The brother of AR8 and the immunizing donor thus seem to share one or more determinants not possessed by AR8.     

Relationship between swimming velocity and lactic concentration during continuous and intermittent training exercises

The present study examined the relationship between lactic acid concentration in capillary blood and swimming velocity during 11 typical endurance exercises (continuous swimming for 30 and 60 min, interval swimming with distances between 50 and 400 m, and with rest periods of 10 and 30 s) and during the "two-speed test" recently described by Mader. It was expected that a better understanding of these relationships could provide evidence how to adjust training intensities from results obtained during the two-speed test. Fifty-nine male swimmers of the German national level participated in this study. After a 30-min maximal swimming test, a mean lactic acid concentration of 4.01 +/- 0.75 mmol/l was found. The corresponding mean velocity was similar to the speed (V4) calculated for the 4 mmol/l level on the basis of the results obtained during the two-speed test (2 X 400). During 30 min continuous swimming at 95% to 105% of the velocity V4, there was a significant correlation (r = 0.82, P less than 0.001) between the swimming speed and the lactic acid concentration. In the 30-min maximal test, the velocity V4 correlated significantly with both the lactic acid concentration (r = -0.58, P less than 0.005) and the swimming speed (r = 0.97, P less than 0.001). During the interval exercises with rest periods of 10 s, the swimming velocities corresponding to the same lactic acid level as during continuous swimming, increased for the 50, 100, 200, and 400 m by 11.23%, 4.21%, 2.95%, and 2.02% of V4, respectively. With rest periods of 30 s, the swimming velocity for the 100, 200, and 400 m increased by 7.34%, 4.22%, and 3.01% of V4, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Biomechanical and biochemical studies of tendon healing after conservative and surgical treatment

Summary Based on clinical studies, it has been proposed that conservative treatment of Achilles tendon ruptures is feasible. However, no biomechanical or biochemical confirmation of this proposal has been presented. In the present investigation the biomechanical and biochemical properties of tendons treated surgically and conservatively after transverse tenotomy were studied. Sixty-eight New Zealand White rabbits were used. A transverse tenotomy of the plantaris longus tendon of the left hind leg was performed. In half of the animals the tenotomy was repaired with a criss-cross silk suture and the limb was immobilized; the other half were treated with immobilization alone. The immobilization was maintained for 4 weeks with a long-leg plastic splint in both groups. After 4, 8, and 16 weeks the tendons were examined regarding biomechanical and biochemical parameters. There were no detectable differences in biomechanical parameters or in tendon elongation between the groups, nor was there any difference in the total hydroxyproline content, the amount of mature and of immature collagen, or the water content. The present findings are compatible with previous favorable reports on conservative treatment of Achilles tendon ruptures and thus suggest interesting clinical possibilities.

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Zusammenfassung Aufgrund klinischer Beobachtungen ist die Auffassung vertreten worden, daß die konservative Behandlung der Achillessehnenruptur vorteilhaft ist. Jedoch fehlt es an biomechanischen und biochemischen Nachweisen dafür. In der vorliegenden Studie wurden die biomechanischen und biochemischen Eigenschaften von Achillessehnen nach einer queren Tenotomie, die entweder genäht oder konservativ behandelt wurde, untersucht. Achtundsechzig New-Zealand-White-Kaninchen bekamen eine quere Tenotomie an der Sehne des M. plantaris longus am linken Hinterbein. Die Tenotomie wurde dann in der Halfte der Falle mit einer criss-cross-Naht (Seide) repariert und das Bein ruhiggestellt, während die andere Hälfte der Versuchstiere nur mit Ruhigstellung behandelt wurde. Die Ruhigstellung des Beines erfolgte vier Wochen lang in einem die ganze Extremität umfassenden Verband aus Hexalite. Nach vier, acht und 16 Wochen wurde die Sehne auf ihre biomechanischen und biochemischen Eigenschaften untersucht. Wir sahen keinen Unterschied in den biomechanischen Eigenschaften oder in beobachteten Sehnenverlängerungen in den beiden Gruppen. Auch der Gesamtgehalt an Hydroxyprolin, der Anteil von reifem und unreifem Kollagen und der Wassergehalt waren ohne Unterschied. Die Ergebnisse dieser Untersuchung stimmen überein mit früheren Berichten über die Vorteile der konservativen Behandlung bei der Achillessehnenruptur und sind klinisch bedeutungsvoll.

     

A Systematic Review of Job Loss Prevention Interventions for Persons with Inflammatory Arthritis

Journal of Occupational Rehabilitation - Purpose To present an overview of the evidence of the effect of job loss prevention interventions, aiming to improve work ability and decrease absenteeism...     

Intrauterine light delivery for photodynamic therapy of the human endometrium

Photodynamic therapy is currently being evaluated as a minimallyinvasive procedure for endometrial ablation not requiring anaesthesia.Light penetration depths at 630, 660 and 690 nm and the optimalconfiguration of intrauterine light-diffusing fibres were determinedin 14 human uteri to assist in the design of a light intrauterinedevice. Post-menopausal ex-vivo uteri showed a significantlylower light penetration depth than pre-menopausal uteri. Witha single central diffusing fibre inserted, the fluence ratemeasured in the uterine wall at the most remote point of thecavity decreased to 1.1 ± 0.4% of that measured at closestproximity, whereas it decreased to only 40.0 ± 9.0% withthree fibres. Distension of the uterine cavity with 2 ml ofan optically clear fluid increased the fluence rate at the fundusbetween the fibres at a depth of 2 mm by a factor of 4. We concludethat in normal-sized pre-menopausal uterine cavities, threediffusing fibres will deliver an optical dose above the photodynamicthreshold level at a depth of 4 mm, even in the most remoteareas, in <30 min without causing thermal damage. For distortedand elongated cavities, either slight distension of the cavityor the insertion of a fourth diffusing fibre is required.     

Detection of proinsulin, C-peptide, insulin-A-chain, and glicentin in pancreatic islet cells of early human fetogenesis.

The presence of C-peptide, proinsulin, insulin-A-chain, and glicentin in human fetal pancreatic cells by using the PAP-technique was investigated and the results obtained compared with the occurrence of insulin or glucagon immunoreactive cells. In pancreatic sections obtained from 10 weeks old human fetuses we could identify cells reacting with antibodies directed against C-peptide, proinsulin, and insulin-A-chain. The majority of the cells were found in the duct epithelium and their number increased from the 10th to 14th week forming clusters near the ducts. The number and localization of the cells correspond exactly to the insulin positive cells. The presence of proinsulin and insulin-A-chains is a further proof of biological activity already in an early step of fetal development. The presence of glicentin-positive cells in the 10th week of gestational age as well as cells reacting with glucagon antibodies provide evidence for active glucagon biosynthesis. The number of these cells increased markedly in the 14th week of gestational age.     

Role of intracellular Ca2+ stores in smooth muscle contractions of the guinea pig vas deferens

Summary Guinea pig vas deferens was used as an animal model for alpha-1 adrenoceptor (₁-receptor) mediated contractions in human hyperplastic prostatic tissue. The selective ₁-receptor agonist, phenylephrine (PE), induced fully reversible, dose-dependent contractions antagonized by increasing concentrations of the ₁-receptor blockers prazosin (1–100 nM) and YM 617 (0.1–10 nM). Removal of extracellular Ca²⁺ reduced PE-evoked contractions in a time-dependent manner. Nifedipine (1–1000 nM), a blocker of voltage-dependent L-type Ca²⁺ channels (VDCC), inhibited the PE-induced response by up to 65%. Removal of extracellular Ca²⁺ abolished the ₁-agonist reactivity in a time-dependent fashion. To elucidate the participation of intracellular Ca²⁺ stores in ₁-receptor contractions, the tissue was pretreated with ryanodine (10 M) or thapsigargin (0.1 M), established inhibitors of Ca²⁺ release from intracellular pools. Both substances reduced the PE contractions by up to 80%. Nifedipine suppressed the remaining contractions completely. This provides evidence that Ca²⁺ influx through VDCC and Ca²⁺ release from intracellular stores contribute to ₁-receptor contractions in the guinea pig vas deferens and may be important in obstructive benign prostatic hyperplasia.     

Late complications with the Pritchard Mark II elbow prosthesis

Twenty-three consecutive patients with rheumatoid arthritis who had 26 Pritchord Mark II elbow prostheses were followed prospectively with a mean follow-up of 75 months (range 52 to 101 months). Two patients with three elbow prostheses have died, leaving 21 patients with 23 elbow prostheses for review. At the latest follow-up all the nonrevised elbows had achieved good or excellent results concerning pain relief and elbow motion. According to the data analyzed by a survivorship function-a Kaplan-Meier curve-the early results were promising with 92% of the prostheses surviving the first 5 years; however, only 43% of the prostheses have survived 8 years. Seven prostheses have been revised; the reasons for revision include one infection, one humeral fracture, one loosening of the humeral component, and four disconnections of the hinge. The number with disconnection of the hinge is increasing. Of 16 prostheses still not revised, the x-ray film reveals migration of the pin axle in six. Radiographic signs of component loosening or migration of the axle are not reflected in pain, function, or total score of the elbow.