Active commuting reduces the risk of wrist fractures in middle-aged women-the UFO study.

SUMMARY: Middle-aged women with active commuting had significantly lower risk for wrist fracture than women commuting by car/bus. INTRODUCTION: Our purpose was to investigate whether a physically active lifestyle in middle-aged women was associated with a reduced risk of later sustaining a low-trauma wrist fracture. METHODS: The Umeå Fracture and Osteoporosis (UFO) study is a population-based nested case-control study investigating associations between lifestyle and fragility fractures. From a cohort of ~35,000 subjects, we identified 376 female wrist fracture cases who had reported data regarding their commuting habits, occupational, and leisure physical activity, before they sustained their fracture. Each fracture case was compared with at least one control drawn from the same cohort and matched for age and week of reporting data, yielding a total of 778 subjects. Mean age at baseline was 54.3 ± 5.8 years, and mean age at fracture was 60.3 ± 5.8 years. RESULTS: Conditional logistic regression analysis with adjustments for height, body mass index, smoking, and menopausal status showed that subjects with active commuting (especially walking) were at significantly lower risk of sustaining a wrist fracture (OR 0.48; 95 % CI 0.27-0.88) compared with those who commuted by car or bus. Leisure time activities such as dancing and snow shoveling were also associated with a lower fracture risk, whereas occupational activity, training, and leisure walking or cycling were unrelated to fracture risk. CONCLUSION: This study suggests that active commuting is associated with a lower wrist fracture risk, in middle-aged women.

Mediterranean diet and incidence of hip fractures in a European cohort.

UNLABELLED: Prevention of hip fractures is of critical public health importance. In a cohort of adults from eight European countries, evidence was found that increased adherence to Mediterranean diet, measured by a 10-unit dietary score, is associated with reduced hip fracture incidence, particularly among men. INTRODUCTION: Evidence on the role of dietary patterns on hip fracture incidence is scarce. We explored the association of adherence to Mediterranean diet (MD) with hip fracture incidence in a cohort from eight European countries. METHODS: A total of 188,795 eligible participants (48,814 men and 139,981 women) in the European Prospective Investigation into Cancer and nutrition study with mean age 48.6 years (±10.8) were followed for a median of 9 years, and 802 incident hip fractures were recorded. Diet was assessed at baseline through validated dietary instruments. Adherence to MD was evaluated by a MD score (MDs), on a 10-point scale, in which monounsaturated were substituted with unsaturated lipids. Association with hip fracture incidence was assessed through Cox regression with adjustment for potential confounders. RESULTS: Increased adherence to MD was associated with a 7 % decrease in hip fracture incidence [hazard ratio (HR) per 1-unit increase in the MDs 0.93; 95 % confidence interval (95 % CI) = 0.89-0.98]. This association was more evident among men and somewhat stronger among older individuals. Using increments close to one standard deviation of daily intake, in the overall sample, high vegetable (HR = 0.86; 95 % CI = 0.79-0.94) and high fruit (HR = 0.89; 95 % CI = 0.82-0.97) intake was associated with decreased hip fracture incidence, whereas high meat intake (HR = 1.18; 95 % CI = 1.06-1.31) with increased incidence. Excessive ethanol consumption (HR high versus moderate = 1.74; 95 % CI = 1.32-2.31) was also a risk factor. CONCLUSIONS: In a prospective study of adults, increased adherence to MD appears to protect against hip fracture occurrence, particularly among men.

Physical activity in middle-aged women and hip fracture risk: the UFO study.

UNLABELLED: In a population-based case-control study, we demonstrate that middle-aged women who were active with walking or in different physical spare time activities were at lower risk of later sustaining a hip fracture compared to more sedentary women. INTRODUCTION: In middle-aged women participating in the Umeå Fracture and Osteoporosis (UFO) study, we investigated whether physical activity is associated with a subsequent decreased risk of sustaining a hip fracture. METHODS: The UFO study is a nested case-control study investigating associations between bone markers, lifestyle, and osteoporotic fractures. We identified 81 female hip fracture cases that had reported lifestyle data before they sustained their fracture. Each case was compared with two female controls who were identified from the same cohort and matched for age and week of reporting data, yielding a total cohort of 237 subjects. Mean age at baseline was 57.2 ± 5.0 years, and mean age at fracture was 65.4 ± 6.4 years. RESULTS: Conditional logistic regression analysis with adjustments for height, weight, smoking, and menopausal status showed that subjects who were regularly active with walking or had a moderate or high frequency of physical spare time activities (i.e. berry/mushroom picking and snow shovelling) were at reduced risk of sustaining a hip fracture (OR 0.14; 95% CI; 0.05-0.53 for walking and OR 0.19; 95% CI; 0.08-0.46, OR 0.17, 95% CI; 0.05-0.64 for moderate and high frequency of spare time activities, respectively) compared to more sedentary women. CONCLUSION: An active lifestyle in middle age seems to reduce the risk of future hip fracture. Possible mechanisms may include improved muscle strength, coordination, and balance resulting in a decreased risk of falling and perhaps also direct skeletal benefits.

Investment in testes, sperm-duct glands and lipid reserves differs between male morphs but not between early and late breeding season in Pomatoschistus minutus.

This study of the sand goby Pomatoschistus minutus, a nest-holding fish with paternal care, focused on gonadal investment among males of different sizes collected early and late in the breeding season. All males caught at the nest had breeding colour, whereas trawl-caught fish consisted of males both with and without colour. The absence or presence of breeding colour was a good predictor of testes investment. Compared to males with breeding colour, males without colour were smaller in body size but had extraordinarily large testes. In absolute terms, testes mass of males without breeding colour was on average 3.4 times greater than those of males with breeding colour. Since small colourless males are known to reproduce as sneaker males, this heavy investment in testes probably reflects that they are forced to spawn under sperm competition. Contrary to testes size, sperm-duct glands were largest among males with breeding colour. These glands produce mucins used for making sperm-containing mucous trails that males place in the nest before and during spawning. Since both sneakers and nest-holders potentially could benefit from having large glands, this result is intriguing. Yet, high mucus production may be more important for nest-holders, because it also protects developing embryos from infections. There was no significant effect of season on body size, testes or sperm-duct glands size, but colourless males tended to be less common late in the season. Possibly this may indicate that individual small colourless males develop into their more colourful counterparts within the breeding season.

Fueling of a marine-terrestrial ecosystem by a major seabird colony.

Seabirds redistribute nutrients between different ecosystem compartments and over vast geographical areas. This nutrient transfer may impact both local ecosystems on seabird breeding islands and regional biogeochemical cycling, but these processes are seldom considered in local conservation plans or biogeochemical models. The island of Stora Karlsö in the Baltic Sea hosts the largest concentration of piscivorous seabirds in the region, and also hosts a large colony of insectivorous House martins Delichon urbicum adjacent to the breeding seabirds. We show that a previously reported unusually high insectivore abundance was explained by large amounts of chironomids-highly enriched in δ15N-that feed on seabird residues as larvae along rocky shores to eventually emerge as flying adults. Benthic ammonium and phosphate fluxes were up to 163% and 153% higher close to the colony (1,300 m distance) than further away (2,700 m) and the estimated nutrient release from the seabirds at were in the same order of magnitude as the loads from the largest waste-water treatment plants in the region. The trophic cascade impacting insectivorous passerines and the substantial redistribution of nutrients suggest that seabird nutrient transfer should be increasingly considered in local conservation plans and regional nutrient cycling models.

A novel NGFB point mutation: a phenotype study of heterozygous patients.

OBJECTIVE: A family with neurological findings similar to hereditary sensory and autonomic neuropathy type V having a point mutation in the nerve growth factor beta (NGFB) gene was recently described. The homozygous genotype gives disabling symptoms. The purpose of the present study was to evaluate the symptoms in heterozygous patients. METHODS: 26 patients heterozygous for the NGFB mutation (12 men, mean age 50 (13-90) years) were examined clinically and answered a health status questionnaire, including the Michigan Neuropathy Screening Instrument (MNSI). 28 relatives (15 men, mean age 44 (15-86) years) without the mutation served as controls in the clinical examination part. 23 of the heterozygotes were examined neurophysiologically and six heterozygous patients underwent a sural nerve biopsy. RESULTS: The heterozygous phenotype ranged from eight patients with Charcot arthropathy starting in adult age and associated with variable symptoms of neuropathy but without complete insensitivity to pain, anhidrosis or mental retardation, to 10 symptom free patients. There was no difference in MNSI between the young heterozygous cases (<55 years old) and the controls. Six of 23 heterozygous patients had impaired cutaneous thermal perception and 11 of 23 had signs of carpal tunnel syndrome. Sural nerve biopsies showed a moderate reduction of both small myelinated (Adelta) and unmyelinated (C) fibres. No apparent correlation of small fibre reduction to symptoms was found. CONCLUSIONS: The NGFB mutation in its heterozygous form results in a milder disease than in homozygotes, with a variable clinical picture, ranging from asymptomatic cases to those with Charcot arthropathy appearing in adult age. Particularly age, but perhaps lifestyle factors also, may influence the development of clinical polyneuropathy.

Fracture mechanisms and fracture pattern in men and women aged 50 years and older: a study of a 12-year population-based injury register, Umeå, Sweden.

UNLABELLED: In a study of a 12-year population-based injury register, Umeå, Sweden, we analyzed the fracture mechanisms and fracture pattern in men and women 50 years and older. Low-energy trauma was responsible for the major and costliest part of the fracture panorama, but the pattern differs between age groups. INTRODUCTION: Osteoporosis-related fracture is a major health problem: the number of hip fractures is expected to double to 2030. While osteoporosis is one of many risk factors, trauma is almost always involved. Therefore, we analyzed injury mechanisms in patients aged over 50. METHODS: We registered injury mechanism, cause, diagnosis in all trauma patients at Umeå University hospital, Sweden. This population-based register (1993-2004) comprises a total of 113,668 injuries (29,189 fractures). Patients >or=50 years contributed to 13,279 fractures. RESULTS: Low-energy trauma (fall <1 m) caused 53% of all fractures >or=50 years and older. In those over 75 low-energy trauma caused >80%. The seasonal variation of fractures was maximally 25%. With increasing age, proximal fractures became more common, in both upper and lower extremities. Proximal locations predominate in older age groups. CONCLUSIONS: Low-energy trauma was responsible for the largest and costliest part of the fracture panorama. In fact, almost all fractures in middle-aged and old people were caused by low-energy mechanisms; thus, most fractures in these patients have a fragility component, and the contribution of osteoporosis-related fractures is more important than previously thought. A better understanding of injury mechanisms also in low-energy trauma is a prerequisite for preventive interventions.

Parathyroid cell number and size in hypercalcemic rats: a stereologic study employing modern unbiased estimators.

Recently developed stereologic methods for unbiased estimations of particle number and size were employed to study parathyroid growth in normal and hypercalcemic young rats. Thus, the parathyroid cell number and size of parathyroid secretory cells were estimated by both the disector method and the volume-weighted mean volume method. The glandular volume was calculated from serial sections, and the volume density of secretory cells was estimated by conventional stereologic techniques. Three groups of animals were studied: normal rats at 3 weeks of age, hypercalcemic rats at 7 weeks of age, and age-matched controls. Hypercalcemia was induced by feeding the animals a purified diet that was nutritionally adequate except for low amounts of phosphate (0.02%) from 3 weeks of age. During the period from 3 to 7 weeks of age, the number of parathyroid secretory cells increased by 100%, whereas the mean cell volume increased by 20%. However, when calculated per gram body weight the volume and number of cells were larger in the younger animals. The phosphate-depleted animals grew slowly and developed severe hypercalcemia. Their parathyroid secretory cells were smaller, and each gland contained fewer cells than in age-matched controls. The lower cell number and cell volume, however, were proportional to the reduced body weight. Data from the 3-week-old animals indicate that the reduced cell number and size in hypercalcemic rats reflected growth arrest rather than atrophy.

Fibromodulin distribution and association with collagen.

Fibromodulin, an acidic 59-kDa proteoglycan, binds to collagen and inhibits collagen fibril formation in vitro. To determine whether fibromodulin is also bound to collagen in vivo, we used immunocytochemical methods to study the spatial relation of the proteoglycan to collagen fibrils in cartilage and tendon. We also studied the quantitative distribution of fibromodulin among compartments in articular cartilage at the ultrastructural level. Fibromodulin was identified with polyclonal antibodies raised in rabbits, and immunoreactivity was detected with protein-A gold. As the major proportion of fibromodulin immunoreactivity was localized along the periphery of the collagen fibrils, the relationship to the banding pattern of the collagen fibrils was mapped. The proteoglycan showed a non-random distribution, with preference to the gap region, axially within the D-period. Reactivity differed among the tissue compartments, with the lowest degree of labelling pericellularly, increasing with distance from the cell, the highest levels being observed in the interterritorial matrix. Labelling density was highest at the articular surface, gradually decreasing towards the cartilage-bone junction. The correlation between collagen fibril diameter and fibromodulin concentration also varied among compartments. Thus, the ratio of fibromodulin to collagen surface density was highest at the surface of the joint cartilage, exhibiting a gradient with higher values in the territorial matrix, decreasing towards the cell in all layers. These findings indicate that fibromodulin represents a factor used by chondrocytes to regulate assembly and function of collagen fibrils.

Parathyroid cell number and size in hypocalcemic young rats.

Weanling rats were fed diets with normal (1%) or low (0.08% or 0.02%, respectively) Ca content for 28 days prior to sacrifice. The total volume of the parathyroids was estimated from serial sections. Volume density of secretory cells was calculated according to conventional stereological techniques, whereas cell number and cell size were estimated by the dissector method. Compared with controls the animals of the experimental groups developed moderate and severe hypocalcemia and their parathyroids were enlarged with a proportional growth of parenchyma and interstitium. Related to the body weight, secretory cell volume was highest in animals with severe hypocalcemia. In the enlarged glands the size of parathyroid secretory cells was increased by 30-40%, whereas total cell number was unaltered. Thus, the increased parathyroid size was due to cell hypertrophy rather than hyperplasia.

Stereologic studies on collagen in bovine articular cartilage.

In an ultrastructural stereologic study on bovine articular cartilage we found that collagen volume density increased with increasing distance from the joint surface and from the chondrocyte. These results not only corroborate previous biomechanical data of a vertical stiffness gradient, but they also suggest that the mechanical forces are unevenly distributed horizontally. On the other hand, although mean collagen fibril diameter showed large differences between the interterritorial compartments of the three zones, there was a population of slender fibrils in all zones and compartments. Since the coarser fibrils provide the high tensile strength (Nimni 1988), the role of the slender fibrils may be to enhance the deformability of the tissue. Moreover, in spite of substantial differences in mean fibril diameter, collagen surface densities were in the same order of magnitude in the territorial and interterritorial compartments, and only slightly lower in the pericellular compartments. The surface parameter may be important for specific molecular interactions. The collagen fibrils have different polarity, i.e. the direction of the fibrils appears to be parallel and antiparallel, about 50% running in each direction. This, together with the very high length/diameter ratio (Clark 1985), may indicate that each fibril is assembled by the concerted action of many cells. The characteristic properties of articular cartilage depend on interactions between its macromolecular components, and the present quantitative data form a basis for discussions on the specificity and regulation of such interactions.

Ultrastructural changes in primary guinea pig osteoarthritis with special reference to collagen.

Collagen fibril distribution and surface and volume densities in proximal tibial articular cartilage were measured in 6- and 12-month-old Dunkin-Hartley guinea pigs developing primary osteoarthritis. At 12 months, gross fibrillation and ulceration of the articular cartilage were observed on the medial but not on the lateral condyle. Collagen volume density decreased with age in the interterritorial compartments in the superficial zone, medially by 16% and laterally by 8%. In the upper radial zone, collagen volume density decreased interterritorially by 10% on the medial condyle only. Despite gross osteoarthritic changes, only moderate and predominantly focal ultrastructural collagen changes were observed. Thus neither gross network disruption nor fibril thickening seems to be a general feature in early guinea pig osteoarthritis.

Quantitative and three-dimensional aspects of the rat parathyroid gland in normo-, hypo-, and hypercalcemia.

The ultrastructure of the rat parathyroid has been under study for more than 35 years, but controversies still exist, especially regarding structure-function relationships. The present review focuses on recent morphological parathyroid research on rats under normal conditions and in various states of disturbed calcium metabolism. To facilitate discussions on functional aspects, current biochemical data, particularly those dealing with the regulation of parathyroid hormone synthesis and release, are also considered. Our results from quantitative studies and from investigations employing serial sectioning form the basis for the discussions. A central issue is whether the parathyroid secretory cells undergo secretory cycles. Prompted by results obtained from improved fixation procedures and serial sectioning, we question the basis for the theory of secretory cycles. Since the rat parathyroid secretory cell is polar, a single section is not an appropriate sample for estimating functional activity and for comparing the structure and distribution of intracellular components of adjacent cells. The heterogeneity in ultrastructural appearance of intracellular vesicles calls for the use of specific markers in relating the structure of the vesicular compartment to intracellular processing of hormone. The importance of unbiased quantitative techniques is illustrated in discussions on cell number and size for estimating the response of the parathyroid gland to different functional states or disorders demanding changes in secretion of parathyroid hormone, e.g., hyper- and hypocalcemia.

Primary osteoarthrosis in guinea pigs: a stereological study.

Volumes and surfaces of articular cartilage and subchondral bone of the proximal tibial epiphysis were measured by unbiased stereological methods on the light microscopic level in groups of 6, 12, and 30-month-old (adult, middle-aged, and old) guinea pigs with primary osteoarthrosis. At 12 months, structural changes similar to those of human osteoarthrosis had developed, predominantly on the central medial condyle, which was not covered with meniscus. The lateral condyle was virtually unaffected; this allowed separate analysis of age-related and disease-related changes. Fibrillation and destruction of cartilage was accompanied by a simultaneous increase of the volume of both cartilage (66%) and subchondral bone (50%). The epiphyseal volume increased by 27% at 12 months, predominantly on the medial (osteoarthrotic) condyle, whereas the volume of the lateral condyle increased only in the oldest age group; this indicated that the joint has a potential for growth and remodeling. Joint growth has been suggested as a pathogenic factor in osteoarthrosis. The 65% increase in thickness noted in subchondral bone was a further indication of the importance of proliferative bone changes in early osteoarthrosis. The low variability of osteoarthrosis in this animal model makes it possible to obtain stable quantitative data from relatively small groups of animals.

Tracking of changes in latency and amplitude of the evoked potential by using adaptive LMS filters and exponential averagers.

The adaptive LMS algorithm in combination with exponential averagers are compared to the use of exponential averagers only in tracking latency and amplitude changes in the evoked potential. The estimator is intended for use in applications where neurologic functions are monitored by detecting changes in the evoked potential. Two different structures of the estimator are evaluated and it is found that averaging before filtering is to be preferred. It is shown that the desired signal to the LMS-filter can have a rather low SNR with only mirror influence on the estimator performance. The estimator which combines an LMS-filter and an exponential averager was shown to detect changes in latency faster than the estimator which uses a nonfiltered average. The LMS-filter is shown to exhibit bias in the estimate of the evoked potential due to the fact that response and background spectra has overlapping frequency ranges. The bias seems not to affect the latency estimation while amplitude estimation was clearly affected. Simulations are performed with both white noise and EEG background.

Long-term results of Boston brace treatment on vertebral rotation in idiopathic scoliosis.

The long-term effect of Boston brace treatment was investigated by computed tomography measurements before treatment, after bracing, and at mean follow-up at 8.5 years in 25 patients with idiopathic scoliosis. At follow-up, the pretreatment Cobb angle, the vertebral rotation, the rib hump, and the translation of the apical vertebra were not significantly changed. The sagittal diameter of the thoracic cage was significantly decreased at follow-up. The current study demonstrates that the Boston brace does not improve, but prevents progression of vertebral rotation, translation, rib hump, and Cobb angle in idiopathic scoliosis. The reduced sagittal diameter is noteworthy and may be of importance for cosmesis and pulmonary function.

The synthesis of metoprolol monitored using Raman spectroscopy and chemometrics.

The synthesis of Metoprolol base was studied using Raman spectroscopy with a 785-nm laser, optical fibres, a holographic transmission grating, confocal optics and a charge-coupled device (CCD) detector. The reaction mixture was heated according to a temperature gradient and spectra of the reaction mixture were obtained by focusing the laser beam through ordinary reaction flasks. Because of overlapping bands, multivariate techniques such as principal components analysis (PCA) and partial least-squares projections to latent structures (PLS) were used in the evaluation of the obtained spectra. The use of PCA or PLS against time does not require any calibration samples and a quantitative calibration is not necessary in order to monitor the reaction. A method for reaction endpoint determination, based on euclidean distances in the score space, is presented. The use of multivariate batch control charts have been demonstrated and a number of problems and solutions regarding the sample presentation have been discussed. The effect of spectral pretreatment on the multivariate results is shown and discussed. The monitoring results show that the time to produce Metoprolol base could be reduced.

Prediction of the outcome after hip fracture in elderly patients.

We report a prospective study of 232 consecutive patients with hip fractures. All were over 64 years of age and living independently before admission to a geriatric orthopaedic ward. We assessed the value, at admission, of predicting factors for independent living at one year after injury. The most important factors were: (1) preinjury function in activities of daily living (grade A or B on the Katz et al (1963) scale); (2) absence of other medical conditions which would impair rehabilitation; and (3) cognitive function better than 7 on the Pfeiffer (1975) mental questionnaire. The odds ratios (95% CI) for these three predictors were 3.5 (1.3 to 9.1), 2.9 (1.3 to 6.1) and 2.4 (1.9 to 4.9), respectively. When all predictors were positive at admission, 92% were living independently at one year; with one, two or three negative predictors, the percentages living independently were 76, 61 and 27, respectively. The median values of the total number of days in hospital, irrespective of diagnosis, during the first year were 12, 24, 29 and 149 days for the four groups. The mortality at one year was predictable on admission only by the number of medical conditions: with no other diagnosis than the fracture the mortality was 0%; with one or two additional conditions the mortality was 14%; and with three or more additional diagnoses it was 24%. These simple and robust predictors can be used to optimise resources for rehabilitation.

The axis of rotation of the ankle joint.

The axis of the talo-crural joint was analysed by roentgen stereophotogrammetry in eight healthy volunteers. Examinations were performed at 10 degrees increments of flexion and pronation/supination of the foot as well as medial and lateral rotation of the leg. Results indicate that the talo-crural joint axis changes continuously throughout the range of movement. In dorsiflexion it tended to be oblique downward and laterally. In rotation of the leg, the axis took varying inclinations between horizontal and vertical. All axes in each subject lay close to the midpoint of a line between the tips of the malleoli. Our study indicates that the talo-crural joint axis may alter considerably during the arc of motion and differ significantly between individuals. This prompts caution in the use of hinge axes in orthoses and prostheses for the ankle.