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Rib bone biopsy samples are often used to estimate changes in skeletal mineral reserves in cattle but differences in sampling procedures and the bone measurements reported often make interpretation and comparisons among experiments difficult. 'Full-core' rib bone biopsy samples, which included the external cortical bone, internal cortical bone and trabecular bone (CBext, CBint and Trab, respectively), were obtained from cattle known to be in phosphorus (P) adequate (Padeq) or severely P-deficient (Pdefic) status. Experiments 1 and 2 examined growing steers and Experiment 3 mature breeder cows. The thickness of cortical bone, specific gravity (SG), and the amount and concentration of ash and P per unit fresh bone volume, differed among CBext, CBint and Trab bone. P concentration (mg/cc) was closely correlated with both SG and ash concentrations (pooled data, r=0.99). Thickness of external cortical bone (CBText) was correlated with full-core P concentration (FC-Pconc) (pooled data, r=0.87). However, an index, the amount of P in CBext per unit surface area of CBext (PSACB; mg P/mm2), was more closely correlated with the FC-Pconc (pooled data, FC-Pconc=37.0+146×PSACB; n=42, r=0.94, RSD=7.7). Results for measured or estimated FC-Pconc in 10 published studies with cattle in various physiological states and expected to be Padeq or in various degrees of Pdefic status were collated and the ranges of FC-Pconc indicative of P adequacy and P deficiency for various classes of cattle were evaluated. FC-Pconc was generally in the range 130 to 170 and 100 to 120 mg/cc fresh bone in Padeq mature cows and young growing cattle, respectively. In conclusion, the FC-Pconc could be estimated accurately from biopsy samples of CBext. This allows comparisons between studies where full-core or only CBext biopsy samples of rib bone have been obtained to estimate changes in the skeletal P status of cattle and facilitates evaluation of the P status of cattle.

While recent forensic research has focused on determining which skeletal elements are superior in their preservation of DNA over the long term, little focus has been placed on measuring intra-element variation. Moreover, there is a general belief that dense (cortical) bone material will contain better-preserved DNA than does spongy (cancellous) bone. To address these ideas, quantitative PCR was used to estimate the degree of mitochondrial DNA (mtDNA) preservation variance across sections of 19 northern fur seal ribs (Callorhinus ursinus) that date to ∼3000 years before present. Further, we developed a measure called the "density index" that was used to gauge the relative densities of the rib sections studied here to determine if density was an appropriate predictor of preservation. The average preservation among the samples was significantly different (ANOVA, p=1.9×10(-9)) with only 15% of the total variance observed within samples. However, 12 of the 19 specimens (∼63.2%) exhibited at least an order of magnitude difference in mtDNA preservation across the whole. Regression of the amount of mtDNA extracted per gram of bone material against the density index of the bone from which it was extracted demonstrates no relationship between these variables (R(2)=0.03, p=0.28)., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Mineral content in samples of ribs, cranium, vertebra, sternum, diaphyses of long bones of lower extremities was analyzed in Urals residents in association with their age and gender. Bone mineral content was estimated in terms of gram per kilogram of wet weight of the sample. The period of sampling and measurements was 1958-1998, ages of persons studied varied form 0 to 99 years, the range of their years of birth was 1872-1984, total number of samples was 6901. The following regularities were found: 1) the rate of increase in bone mineral density in the period of childhood and youth varied from 1.3-1.5% per year in the rib to 0.5-0.9% per year in cranium and fibula; 2) for some bones (vertebrae, fibula, sternum, cranium) a period of insignificant changes of bone mineral content was observed; 3) the rate of bone mineral loss in elderly persons was dependent on gender and bone type, the rate was estimated in the range from 0.8% per year (fibula, in females after the age of 50) to 0.2-0.3% per year for other regions of the skeleton in both men and women. The comparison of data on bone mineral content obtained with different methods, is presented.

A study was conducted to monitor changes in cortical bone mineral in the dairy cow in response to demands of lactation and pregnancy using rib bone biopsies in serial sampling. Sixteen Friesian cows from the University dairy herd were used to collect 9 samples during the lactation period and 5 samples during the dry period. The data were analysed using a split-plot design analysis of variance. There were no significant (P > 0.05) differences in cortical bone phosphorus concentrations in rib bone during the lactation period, but calcium concentrations in cortical bone were significantly (P < 0.05) higher at parturition and during the first 30 days of lactation compared to the next 30 days and between 90 and 120 days. Results reported here indicate that the cow resorbs cortical bone during the middle of the lactation period and not during the periparturient period as previously thought. Magnesium concentrations were also significantly (P < 0.05) higher at the beginning of lactation compared to some of the other sampling times, but cortical bone was significantly (P < 0.05) thinner at the beginning of lactation compared to several of the other sampling times. There were no significant (P > 0.05) differences in cortical bone Ca or Mg concentrations during the gestation period. Cortical bone P concentrations significantly (P < 0.05) decreased during the first 180 days, but significantly (P < 0.05) increased at 181-230 days and significantly (P < 0.05) decreased again at 231 days to term. Cortical bone thickness decreased significantly (P < 0.05) from the beginning of gestation to term. There were no significant (P > 0.05) differences in cortical bone thickness or Ca or Mg concentrations in cortical bone during the dry period, but cortical bone P concentrations were significantly (P < 0.05) greater at the end of the dry period compared to the first 30 days of the period. In general, cortical bone Ca and Mg values decreased as milk production increased up to 20 kg/day and cortical bone P values and bone thickness increased. In animals producing over 20 kg/day, however, cortical bone mineral values were greater and cortical bone thickness was lower compared to those animals producing less than 20 kg.

It is known that impact loading sport can increase the bone mineral density in the stressed sites of the skeleton in athletes. However, non weight-bearing sites are seldom studied in healthy young girl athletes. In order to study the effects of a long term intensive training on the non-stressed region of the skeleton (skull), we investigated both highly-trained girl athletes, involved in sports requiring or not significant impact loading on the skeleton and a girl control group. Bone mineral content (BMC) and density (BMD) were measured in the whole body, at lumbar spine, femoral neck, trochanter, Ward's triangle, radius, head and ribs, in 60 prepubertal girls including 12 swimmers, 32 gymnasts and 16 controls. Measurements were made by DXA. There were no statistical differences between the groups as regards age, height, body weight, body mass index, lean tissue mass and dietary calcium intake. Mean BMD in gymnasts was statistically higher than in other groups for radius (p < 0.001), femoral neck (p < 0.05) and Ward's triangle (p < 0.05) while there was no difference between swimmers and controls. Head BMC was significantly lower in gymnasts compared to other groups (241.9+/-41 g vs. 285.8+/-34.7 g and 291.1+/-50.2 g respectively in swimmers and controls, p < 0.001). The same observation was made for head BMD (p < 0.01). When body weight was used as a covariant, the contribution of the head BMC to the whole body was significantly lower (p < 0.001) in gymnasts (24.97%) than in swimmers (27.88%) and controls (27.77%). When compared between groups, the slopes of the regressions for head/whole body BMC or BMD were significantly lower in gymnasts (p < 0.05) than in other groups. These data suggest that in prepubertal children the increased bone density induced by gymnastic training in the stressed sites of the body could be related to a decreased skull bone mass.

Measurements of the volume magnetic susceptibility of solids using the classical Gouy balance approach are hampered by variations in apparent density of the packed powder. In this paper a quantitative NMR measurement of the volume magnetic susceptibility of powdered solids is described and the volume susceptibility of bone is reported. The technique is based on the measurement of changes in incremental linewidth (1/pi T2') induced in a marker fluid whose susceptibility can be predictably modified by changing the composition, such as by addition of a soluble diamagnetic compound. The spectroscopic linewidth of the marker fluid is determined by the susceptibility difference between the fluid and the suspended solid. Changes in the linewidth are accompanied by bulk magnetic susceptibility induced frequency shifts in the fluid resonance. Correlating the two dependencies allows measurement of the absolute volume susceptibility of the solid. The susceptibility of bovine rib bone was found to be -0.9 +/- 0.02 x -10(-6) (CGS) confirming previous estimates which suggested bone to be more diamagnetic than the marrow constituents. Knowledge of the susceptibility of bone is relevant in view of the growing interest in MRI osteodensitometric techniques.

Results of longitudinal studies that involved the measurement of lead by different methodologies are presented for two groups of patients with chronic renal disease. Methodologies for all patients included x-ray fluorescence measurements of finger-bone lead. These measurements were conducted 5 y apart for one group of patients (n = 15). Initial measurements for the other group (n = 15) were supplemented by bone lead levels obtained either from skull at craniotomy or from skull, and sometimes rib, at autopsy. Most subjects also underwent ethylenediaminetetraacetic acid (specifically CaNa2 EDTA) lead-mobilization testing. A correlation between rate of decrease in finger-bone lead and immunoreactive parathormone levels was suggested. Renal patients were compared with age-matched controls, and their bone half-lives did not differ. The data are discussed and related to other results obtained from clinical and nonclinical populations in which trabecular and cortical bones were studied, and our results were consistent with evidence that more rapid turnover of lead occurs in trabecular bone than in cortical bone. No support was found for the hypothesis that patients who undergo renal dialysis accumulate lead in bone.