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Spontaneous fractures were reported to be rare (less than 1%) in 1664 hospital admissions for hip fracture in the 1950s in Sweden. We report 11 fluoride-treated postmenopausal patients who developed spontaneous fractures of the femoral necks, all subcapital initially. In 7 patients who continued treatment there were later femoral neck or shaft fractures; in 6, these were bilateral (one followed a fall). In all there were 19 spontaneous fractures: 5 were asymptomatic, including 2 with deformity; 12 fractures required surgery. Five were incomplete (stress) fractures. All were treated with supplementary calcium 1 g daily; 10 had vitamin D supplementation. In all patients where the timing was known, the initial and subsequent fractures were preceded by, or associated with increased bone turnover as measured by plasma alkaline phosphatase (pAlP) (i.e., they were all "good responders"). Two had pretreatment hip fractures following falls. We compared these 11 (Group 1) and another identically treated group of 14 patients (Group 2), without spontaneous femoral fractures and not different in mean age, pretreatment vertebral fractures, years since menopause, fluoride dosage, and plasma creatinine. Group 1 had a lower (p less than 0.05) index of cortical bone in the femoral neck, as assessed by the ratio "calcar width/femoral neck minimum width." The 6 biopsied fluorotic patients from Group 1 had a higher (p less than 0.05) bone fluoride content than the 4 biopsied fluorotic patients from Group 2. Furthermore, histological cortical features of thinning, increased porosity, and advanced tunneling resorption characterized Group 1 posttreatment biopsies. There were no significant differences in peak pAlP responses in the two groups. Mild asymptomatic vitamin D excess may have been a contributing factor in three Group 1 patients. Two further treatment groups have been studied more recently by forearm single-photon absorptiometry (SPA) at two sites; a cyclic NaF group (Group 3) and a calcium +/- vitamin D group (Group 4). Neither showed significant changes in forearm cortical bone density on treatment for 2 and 1.5 years, respectively, but Group 3 showed a significant increase in density at an ultradistal (60% trabecular) site. The pAlP response in Group 3 was significantly less than in Group 1. Spontaneous femoral neck or shaft fractures did not occur in either Groups 3 or 4. Therefore, we recommend: (1) Avoidance of sodium fluoride (NaF) treatment if pretreatment femoral fracture or thin femoral neck cortices exist.(ABSTRACT TRUNCATED AT 400 WORDS)

Born-Oppenheimer eigenergies (EnJ ) of the ro-vibrational (n, J) quasibound levels of 4HeH+ in the X1Σ+ electronic state are calculated using an improved outer boundary condition and their values are compared with those of three other methods, namely, the uniform JWKB quadratic approximation, the application of an outer boundary condition pertaining to the irregular Bessel function and the maximization of the time-delay function. The widths (Γ nJ ) of these states obtained by semiclassical and quantum techniques are also compared. The boundary condition may be applied to other diatomic ionic orbiting complexes (i.e. H2 +) which dissociate via the decay of quasibound states to an ion and a neutral atom. For the broader resonances, the differences between various estimates of a particular EnJ can exceed the diagonal nuclear-motion correction.

Die Konformerengleichgewichte verschiedener monosubstituierter Cyclooctane werden durch 13CMR-Tieftemperatur-Spektroskopie bestimmt. Aus den 13C-Verschiebungen kann auf die Geometrie der Konformeren geschlossen werden. Durch Vergleich berechneter und experimenteller Spektren werden fur die Konformerenumwandlungen einige ΔG#-Werte erhalten. The conformational equilibria of a variety of monosubstituted cyclooctanes is determined by low temperature 13CMR spectroscopy. 13C shifts allow conclusions to be made regarding the geometry of the conformers. For some conformational processes ΔG# is obtained by complete line shape analysis.

The dipolar and the spin-rotation mechanism are both involved in the relaxation of the 13C nuclei. Their respective contributions are evaluated from the nuclear Overhauser effect in the presence and absence of Cr(acac)3, and confirmed through the study of the temperature dependence of T 1. The molecular rotation appears to be isotropic, and to proceed according to the Debye diffusion mechanism at 296 K.

Hemiplegia is associated with excessive bone loss in the paralyzed arm. The forearm bone mineral content was measured at a proximal cortical site and a distal trabecular site of both the normal and hemiplegic arms in 74 patients with hemiplegia. By comparing the ratios of bone mineral content in the two arms, the effect of immobilization could be quantitated independently of the large population variance in bone mineral content. Bone loss, estimated from this single comparison of bone mineral content in the normal and hemiplegic arms, at the trabecular and cortical sites was positively correlated with the duration of stroke and negatively correlated with reduction in forearm function. At the trabecular site females had a proportionately greater bone loss than males, indicating an interaction between gender and immobilization associated bone loss at this site. The regression line of excess bone loss in the hemiplegic limb against time had a negative slope of 1.3% and 1.5% a year of the starting value for the trabecular and cortical sites, respectively, over the 15 years studied. This study indicates that a reduction in function is associated with significant bone loss occurring over prolonged periods that may account, at least in part, for the significant osteoporosis seen in elderly people and in subjects with conditions resulting in reduced mobility such as arthritis, obstructive airways disease, and neurological disease.

Routine estimation of plasma calcium has made the finding of asymptomatic hypercalcaemia a frequent occurrence. A high index of suspicion for familial hypocalciuric hypercalcaemia (FHH) will lead to accurate diagnosis and avoidance of unnecessary parathyroid surgery. Four FHH kindreds with 16 hypercalcaemic members were found in an unselected referral population over 3 years. Differentiation from primary hyperparathyroidism (42 patients in the same period) was facilitated by analysis of fasting blood and urine for renal handling of calcium, phosphate and cyclic AMP. We found that a plot of serum PTH against fasting calcium excretion separated all cases of each disorder. The discriminatory power of these two variables was confirmed by multivariate discriminant function analysis. An elevated plasma chloride was found to be common to both diseases and of no value in differentiation.