Plasma-sprayed ceramic coatings of fluorapatite (FA), magnesiumwhitlockite (MW), and hydroxylapatite (HA), and noncoated Ti-6Al-4V alloy (Ti) implants were evaluated histologically and histomorphometrically in a goat animal study. Cylindrical Ti-6Al-4V plugs were plasma-spray-coated with FA, MW, and HA. Noncoated, grit-blasted Ti plugs served as controls. The plugs were implanted into the right femur and left humerus of 20 adult goats. The results were evaluated using descriptive histology and histomorphometry. The histomorphometry consisted of measurements of bone apposition and coating thickness. The results demonstrated that FA showed a high amount of bone apposition without signs of degradation or dissolution. MW showed considerable reduction in thickness and at 12 weeks an adverse tissue reaction. However, at 25 weeks the amount of bone apposition was significantly increased compared with the 12-week implants. HA revealed considerable and progressive reduction in thickness and at 25 weeks a lower amount of bone apposition than FA and MW. At 12 weeks the Ti implants did reveal bone apposition, although frequently localized fibrous tissue was visible. At 25 weeks the Ti implants did not differ in bone apposition from the HA implants. Further studies are necessary on the effect of degradation or dissolution of HA on the compatibility with bone.

Mentally healthy subjects show increased plasma concentrations of the neuropeptides, arginine vasopressin (AVP) and oxytocin (OT), under conditions of stress, but data are lacking about plasma concentrations of AVP and OT in patients with major depression. We thus assessed plasma concentrations of AVP and OT in patients with major depression (n = 52) and healthy controls (n = 37). Mean plasma AVP concentrations were higher in the group of depressed patients than in controls. A subgroup of 16 patients showed very high levels of plasma AVP, but no other feature differentiating this subgroup from the other patients was found. In-patients showed higher plasma AVP levels than out-patients, and melancholic patients had higher plasma AVP levels than did nonmelancholic patients. Plasma AVP levels were slightly related to psychomotor retardation and significantly inversely to neuroticism. Patients' plasma OT concentrations had a wider range than in controls. AVP and AVP-mediated functions may be a factor in the clinical picture of depression, possibly by influencing the activity of the hypothalamic-pituitary-adrenal axis.

The objective of this questionnaire-based survey was to evaluate the prevalence and causes of sleep disturbances in 90 nondepressive patients with Parkinson's disease (PD) and 71 age-matched healthy subjects. We also assessed the prevalence and characteristics of excessive daytime sleepiness (both groups) and excessive fatigue (PD patients). A high prevalence of sleep disturbances in PD patients was found; this is to a large extent probably the result of aging. As compared with controls, patients had a more severely disturbed sleep maintenance because of nycturia, pain, stiffness, and problems with turning in bed. The prevalence of excessive dreaming is similar in both groups, but altered dream experiences almost exclusively occurred in PD. Patients rated themselves more often to be morning-types than controls. This finding may account for the reported adaptation effects in experimental settings and the reduced REM latency in PD patients. The prevalence of daytime sleepiness was similar in both groups. Excessive daytime sleepiness showed a clear diurnal pattern with a peak in the early afternoon. As for excessive fatigue, the majority of the patients did not report a preferential time for this symptom. Our findings further argue against an association of fatigue with any circadian factor, and instead suggest a relationship with the motor deficits of PD.

The authors studied the reproducibility of repeated measurements of left ventricular volumes, weight, and wall stress as determined with cine and spin-echo magnetic resonance (MR) imaging. Two observers analyzed 40 serial MR imaging examinations twice, yielding a total of 160 repeated measurements. Estimates of 95% ranges for change were ejection fraction, 10% and 12%; wall mass, 16% and 21%; and wall stress, 22% and 20%, for measurements derived from cine MR imaging and spin-echo MR imaging, respectively. Reproducibility was not significantly different between cine and spin-echo MR imaging. Intraobserver, interobserver, and interexamination errors were quantitated with variance component analysis. Interexamination variability was the single most important contributor to total variance. Reproducibility of left ventricular chamber volume measurements with MR imaging is superior to that of other imaging modalities. In addition, MR imaging can provide reliable estimates of wall mass and wall stress. Efforts to improve reproducibility should be aimed at lowering interexamination variability.

Genetic factors associated with rheumatoid arthritis (RA) might involve variant tumour necrosis factor (TNF)-alpha genes. Therefore, polymorphisms at positions -308, -238, -376, -163 and +70 relative to the transcription initiation site were studied with respect to the susceptibility to, or severity of, RA. TNF-alpha genotypes of 283 RA patients and 116 healthy individuals were determined. Clinical data were obtained from patient files and questionnaires. The distribution of TNF-alpha alleles was similar in RA patients and healthy controls. With respect to disease severity, the TNF-alpha -238GA genotype was found to be associated with the absence of erosions [odds ratio (OR) 4.1, confidence interval 1.0-17]. In addition, this genotype was associated with a lower number of hand joints affected by erosions within the first 3 yr of disease onset compared to -238GG. The association between the -238 polymorphism and radiographic progression was independent of the presence of HLA-DR4. In line with this observation, the OR for the presence of erosions in patients with both risk factors (DR4 and -238GG) compared to patients who lack these factors was 11.1 (1.8-6.8). No associations between the TNF-alpha -308, +70 and -376 alleles and susceptibility to, or severity of, RA could be demonstrated. Our data indicate that the TNF-alpha -238GA genotype is associated with decreased radiologically detectable progression of RA.