Evaluation of micromotion in cemented vs uncemented knee arthroplasty in osteoarthrosis and rheumatoid arthritis. Randomized study using roentgen stereophotogrammetric analysis

Twenty-four patients (25 knees) with osteoarthrosis (OA) and 19 patients (20 knees) with rheumatoid arthritis (RA) were operated with bi-tricompartmental knee arthroplasty. The patients were randomized to cemented or cementless fixation of the tibial component. The fixation of the tibial components was examined with roentgen stereophotogrammetric analysis (RSA) up to 24 months after operation. The following parameters representing tibial component micromotion were measured: (1) maximum migration of the prosthetic edge (maximum total point motion, MTPM); (2) distal migration of the prosthetic center (subsidence); (3) maximum proximal movements of the prosthetic edge ("lift-off"); and (4) prosthetic rotations, corresponding to internal/external rotation, adduction/abduction, and forward/backward tilt of the tibial component. All prostheses displayed significant micromotions, which tended to decrease 3-6 months after the operation. The average migration after 2 years, when measured as maximum single axis rotation, and MTPM were about 0.9 degrees-1.5 degrees and 1.0-1.5 mm, respectively, in all four groups. There were no statistically significant differences between cemented and cementless prostheses in either the OA or the RA group. The fixation in the RA patients did not significantly differ from that of the OA patients, perhaps because the RA patients had lower weight and were living a more sedentary life.     

Prediction of survival and recurrence in bladder carcinoma

Summary We have followed a large population of patients receiving radiation treatment for bladder carcinoma with respect to survival and recurrence-free survival. Bivariate and multivariate life table analyses have been performed using a set of independent variables. The most important were T class, grade (G), urinary carcinoembryonic antigen (U-CEA) taken before treatment and cytological analysis 4 months after treatment. We compared the usual way of classifying a patient (T+G) with the combination of U-CEA and cytology since the latter two variables seemed to have great prognostic importance. The analyses show that T+G gives the best significance for survival (P=0.0003) while U-CEA and cytology is better for recurrence-free survival (=0.0002). 0.0002).     

8-hydroxy-2-(di-n-propylamino)tetralin, 8-OH-DPAT,a potent and selective simplified ergot congener with central 5-HT-receptor stimulating activity

Summary It was demonstrated that the simplified ergot congener 8-hydroxy-2-(di-n-propylamino)tetralin, 8-OH-DPAT, is able to elicit pronounced biochemical and behavioural alterations indicative of central serotoninomimetic activity. Since these effects are resistant to prior monoamine depletion and/or synthesis inhibition by means of reserpine and-propyldopacetamide (H22/54), respectively, they are most likely to be attributable to direct serotonin-receptor agonism by 8-OH-DPAT. With regard to central 5-HT neurotransmission the effects of 8-OH-DPAT-increased 5-HT levels, decreased 5-HIAA levels, 5-HT-synthesis rate and 5-HT utilization and inhibited 5-HT neuronal firing-are virtually identical, and comparable in potency, to those reported to result from the administration of lisuride or LSD. In contrast, however, to lisuride and LSD (included for comparative purposes in this study) as well as to several differently N-substituted, 5,6-dihydroxy, 6,7-dihydroxy and 5-, 6- and 7-monohydroxy 2-aminotetralins, 8-OH-DPAT lacks appreciable effects on central catecholamine receptors. The compound may thus be regarded the most potent, selective centrally acting 5-HT agonist described to date. accordance with this it was shown that the full-blown 5-HT-like behaviour syndrome induced by 8-OH-DPAT cannot be antagonized by reserpin phenoxybenzamine, propranolol and haloperidol. In addition, of the truputative 5-HT-receptor blockers cyproheptadine, methergoline and methrothepin only the latter was able to counteract the 8-OH-DPAT-induce syndrome. The results are discussed in relation to the recent subclassification of central 5-HT receptor sites.A comparison between the chemical structures and biological activities for different fragments of the ergot nucleus was also made. The data suggest, in that while the role of the A ring in the ergot structure for dopaminer activity at present is unclear, this ring may be important for the 5-HT-receptor activity like in e.g. lisuride and LSD.Moreover, based on the present results and literature reports, it is speculated that a selective 5-HT-receptor agonist such as 8-OH-DPAT would be liable to induce hallucinations in man.Presented in part at the 19th ACNP meeting, San Juan, December 15–19,1980. [Psychoph. Bull.17, 180–183 (1981).]     

Individuals with an increased risk of colorectal cancer: perceived benefits and psychological aspects of surveillance by means of regular colonoscopies.

PURPOSE: To evaluate the psychological consequences of genetic counseling followed by a surveillance program using colonoscopy among individuals with increased risk of colorectal cancer. PATIENTS AND METHODS: Two hundred sixty-five individuals, participating in a surveillance program with colonoscopy, were mailed a survey questionnaire that assessed their experience of the surveillance program and their perception of the risk of colorectal cancer. The Hospital Anxiety and Depression scale and the Swedish Short Form-36 Health Survey was also included. RESULTS: Two hundred forty individuals completed the questionnaire and were divided into the following risk groups: risk group 1, an individual with a mutation in hMLH1 or hMSH2 and a lifetime colorectal cancer risk of 80% (n = 28); risk group 2, a lifetime colorectal cancer risk of 40% (n = 129); and risk group 3, a lifetime colorectal cancer risk of 20% (n = 83). Among all individuals, the mean for perceived benefit was 8.0, and the perception of discomfort was 3.3 on the visual analog scale (1-10). In risk group 1, 61% underestimated personal risks as being 40% or less. Approximately 50% of the subjects in risk groups 2 and 3 either under- or overestimated their lifetime risk. According to the Swedish Short Form-36 Health Survey and the Hospital Anxiety and Depression scale, the study sample resembled the reference population. CONCLUSION: A majority of the study sample understood why they were under surveillance, and regular colonoscopies were well-tolerated. The wide range of risk perception as well as low-risk perception in mutation positive subjects is acceptable, as long as these individuals adhere to surveillance programs and do not demonstrate increased levels of anxiety or depression.     

The effect of the preoperative bone quality on the fixation of the tibial component in total knee arthroplasty

The relationship between the preoperative level of bone mineral density (BMD) in the proximal tibia and the migration of the tibial component 2 years after total knee arthroplasty was investigated in 28 knees with osteoarthrosis (10 men, 18 women; mean age, 71). Sixteen components were inserted uncemented and 12 were cemented. Mean average BMD measured 10 mm below the joint level was 0.81 g/cm2 (range, 0.15-1.33 g/cm2) and was not influenced by gender, age, weight, or preoperative alignment. Local BMD measured in the medial and lateral condyles was influenced by the preoperative alignment. In knees with uncemented fixation, most of the tibial component migration (ie, subsidence and lift-off) occurred within the first months, and thereafter the implants seemed to stabilize. In the uncemented implants, there was a significant relationship between average BMD and migration (regression analysis with curve-fit estimation). The least migration was seen when average BMD was 0.6 to 1.0 g/cm2. Beyond this range, increased subsidence and lift-off was seen. There was no relationship between BMD and the change in maximum migration between 1 and 2 years postoperatively, however. In knees with cemented fixation, subsidence was initially small but continuously increasing. There were no relationships between BMD and subsidence, lift-off, and maximum migration, indicating that bone-cement can compensate for variations in bone quality, at least in the early period after operation.     

The prevalence of respiratory symptoms and asthma among school children in three different areas of Norway

The role of exposure to ambient air pollution has been a topic of interest as a potential risk factor for respiratory symptoms and asthma. We expected that the prevalence rates would vary in Norway between the capital, Oslo, the mountainous area Hallingdal and the industrial area Odda. Surveys were conducted in school children, aged 6-16 years, in; Oslo (n=2577), Hallingdal (n=1177) and Odda (n=831). The parent-reported prevalence of wheeze in past year was almost similar in Oslo (13. 1 (95% CI 11. 7-14. 5)) and Upper Hallingdal (14. 2 (13. 1–15. 3)), but lower in Odda (9. 0 (7. 0–11. 0)). The findings for severe respiratory symptoms were almost equal. The age patters within each area differed. The risk of wheeze ever (p < 0.001) and wheeze in past year (p=0.04) decreased with increasing age in Odda, while there was an increase in the risk of exercise induced wheeze in Oslo (p=0.02) and Hallingdal (p < 0.001). The lifetime prevalence of asthma was lowest in Odda (5. 4 (3. 8–7. 0)) compared to Oslo (9. 4 (8. 2–10. 6)) and Hallingdal (8. 5 (6. 8–10. 2)). There was a positive association between physical activity and wheeze in past year. The results do not support the hypothesis that respiratory morbidity is more common in urban than rural areas, age and physical activity can influence the prevalence rates of respiratory symptoms in school children.     

Growth and survival of B-chronic lymphocytic leukaemia cells

Although chronic lymphocytic leukaemia of B-cell type (B-CLL) is the most common form of leukaemia in the Western world, several questions about the biology of B-CLL remain to be clarified. To obtain a conceptual model for B-CLL, defined as a relentless accumulation of resting B-CLL cells, it is particularly relevant to ask which cell type is the normal counterpart of B-CLL; what is the site of proliferation; which signals are involved in the recruitment and induction of proliferation and which signals contribute to the survival of the B-CLL cells? The significance of the studies on B-CLL cellsin vitro for the interpretation of thein vivo situation may be questioned since they oversimplify the multiple and complex cellular interactions that occurin vivo. However, thein vitro studies have been instrumental in elucidating signals that may regulate growth, differentiation and survival of B-CLL cells. This knowledge, herein reviewed, can be used to put forward a hypothesis on B-CLL cell regulationin vivo.     

Isolated human islets trigger an instant blood mediated inflammatory reaction: implications for intraportal islet transplantation as a treatment for patients with type 1 diabetes

Islet transplantation offers a logical means to treat insulin-dependent diabetes. However, for reasons poorly understood, the clinical results with islet transplantation have been vastly inferior to those obtained with whole organ pancreas transplantation. The conventional technique for transplanting isolated islets is by intraportal injection, with the islets being trapped in the liver. Human islets exposed to human blood trigged an "instant blood mediated inflammatory reaction", IBMIR, characterised by platelet consumption, and activation of the coagulation and complement systems. The islets became surrounded by clots and infiltrated with leukocytes, and there was evidence of islet damage as reflected in insulin dumping. When heparin and a complement inhibitor (SCRI), was added to the system, IBMIR was suppressed and islet damage reduced. After intraportal pig-to-pig islet intraportal allotransplantation similar morphological changes was found, corroborating the in vitro findings. Thus, IBMIR inflicts a significant damage to human islets exposed to human blood and IBMIR will also, most likely, enhance the subsequent specific, cell mediated, rejection. Platelet and complement activation seem to be the most important factors in the pathogenesis of IBMIR. The results presented strongly suggest that IBMIR observed both in vitro and in vivo when isolated islets come in contact with blood could provide an explanation for the unsatisfactory results seen in clinical islet allotransplantation.     

Effects of vasoactive intestinal polypeptide (VIP) on intraocular pressure, facility of outflow and formation of aqueous humor in the monkey

Stimulation of the facial nerve causes a non-cholinergic vasodilation in the uvea and a rise in the intraocular pressure in rabbits, cats and monkeys. Vasoactive intestinal polypeptide (VIP) has been suggested as the neurotransmitter mediating these effects. In the present investigation, the effects of VIP on aqueous humor dynamics were studied in cynomolgus monkeys. After intracameral injection of 1 microgram VIP, the outflow facility was higher in the experimental eye than in the control; 0.42 +/- 0.46 compared with 0.33 +/- 0.03 microliter cm H20-1 min-1, difference 0.09 +/- 0.04 microliter cm H2O-1 min-1. Intravenous infusion of VIP, 160 ng min-1, increased aqueous humor flow from 1.12 +/- 0.07 to 1.65 +/- 0.09 microliter min-1. Almost the same effect, a 50% increase in aqueous humor flow, was found after intracameral administration of 90 micrograms VIP. This dose of VIP caused a significant increase in intraocular pressure (IOP) in the experimental eye. The maximal difference in IOP between the experimental eye and the control eye was 7.5 +/- 0.4 cm H2O. A lower dose of VIP, 30 micrograms intracamerally, increased aqueous humor flow by about 20%, but had no consistent effect on IOP. The effect of VIP on aqueous humor flow was not affected by pretreatment with indomethacin. The results suggest that most of the rise in IOP caused by intracameral VIP administration is due to a rise in the pressure in the veins into which the aqueous humor is drained. Enhanced formation of aqueous humor plays a smaller role. The effects of VIP on aqueous humor formation and outflow facility suggest that the facial nerve may be involved in nervous control of aqueous humor dynamics, as VIP is most probably released in the eye by stimulation of the facial nerve.