MicroRNAs as potential biopredictors for premenopausal osteoporosis: a biochemical and molecular study.

BACKGROUND: Circulating micro-RNAs have been proposed as a new type of biomarker in several diseases, particularly those related to bone health. They have shown great potential due to their feasibility and simplicity of measurement in all body fluids, especially urine, plasma, and serum. AIM: This study aimed to evaluate the expression of a set of mRNAs, namely miR-21, miR-24, mir-100, miR-24a, miR-103-3p, and miR-142-3p. Their proposed roles in the progression of osteoporosis were identified using a real-time polymerase chain reaction (RT-PCR) analysis in premenopausal women. In addition, their correlations with osteocalcin (OC), bone-specific alkaline phosphatase (BAP), and deoxypyridinoline (DPD) bone markers were explored. METHODS: A total of 85 healthy premenopausal women aged 25-50 years old were included in this study. Based on a DXA scan (Z-score) analysis and calcaneus broadband ultrasound attenuation scores (c-BUAs), measured via quantitative ultrasound (QUS), the subjects were classified into three groups: normal group (n = 25), osteopenia (n = 30), and osteoporosis (n = 30). Real-time-PCR and immunoassay analyses were performed to determine miRNA expression levels and serum OC, s-BAP, and DPD, respectively, as biomarkers of bone health. RESULTS: Among the identified miRNAs, only miR-21, miR-24, and mir-100 were significantly upregulated and increased in the serum of patients with osteopenia and osteoporosis, and miR-24a, miR-103-3p, and miR-142-3p were downregulated and significantly decreased in osteoporosis. Both upregulated and downregulated miRNAs were significantly correlated with BMD, c-BUA, OC, s-BAP, and DPD. CONCLUSION: A group of circulating miRNAs was shown to be closely correlated with the parameters BMD, c-BUA, OC, s-BAP, and DPD, which are traditionally used for bone-health measurements. They could be identified as non-invasive biomarkers in premenopausal patients with osteoporosis. More studies with large sample sizes are recommended to estimate the mechanistic role of miRNAs in osteoporosis pathogenesis and to provide evidence for the use of these miRNAs as a non-invasive method of diagnosing clinical osteoporosis, especially in premenopausal patients.

Approach of Supercritical Carbon Dioxide for the Extraction of Kleeb Bua Daeng Formula.

Supercritical fluid extraction (SFE) is an innovative green technology for the extraction of phytochemicals from plants. Therefore, this study aimed to evaluate the application of SFE and to optimize the extraction conditions of the Thai herbal formula, Kleeb Bua Daeng (KBD). A Box-Behnken design (BBD) with response surface methodology (RMS) was used to determine the effect of the extraction time (30-90 min), temperature (30-60 °C), and pressure (200-300 bar) on response variables including the extraction yield, total phenolic content (TPC), total flavonoid content (TFC), total carotenoid content (TCC), and total anthocyanin content (TAC) of the KBD formula. The highest percentage extraction yield (3.81%) was achieved at 60 °C, 300 bar, and 60 min of the extraction time. The highest TPC (464.56 mg gallic acid equivalents/g extract), TFC (217.19 mg quercetin equivalents/g extract), and TCC (22.26 mg ß-carotene equivalents/g extract) were all achieved at 60 °C, 250 bar, and 90 min of the extraction time. On the contrary, it was not possible to quantify the total anthocyanin content as anthocyanins were not extracted by this method. The results indicated that SFE-CO2 is a suitable method of extraction for a green recovery of phytochemicals with low and moderate polarity from the KBD formula.

Quantitative Ultrasound (QUS) in the Management of Osteoporosis and Assessment of Fracture Risk: An Update.

Quantitative ultrasound (QUS) presents a low cost and readily available alternative to DXA measurements of bone mineral density (BMD) for osteoporotic fracture risk assessment. It is performed in a variety of skeletal sites, among which the most widely investigated and clinically used are first the calcaneus and then the radius. Nevertheless, there is still uncertainty in the incorporation of QUS in the clinical management of osteoporosis as the level of clinical validation differs substantially upon the QUS models available. In fact, results from a given QUS device can unlikely be extrapolated to another one, given the technological differences between QUS devices. The use of QUS in clinical routine to identify individuals at low or high risk of fracture could be considered primarily when central DXA is not easily available. In this later case, it is recommended that QUS bone parameters are used in combination with established clinical risk factors for fracture. Currently, stand-alone QUS is not recommended for treatment initiation decision making or follow-up. As WHO classification of osteoporosis thresholds cannot apply to QUS, thresholds specific for given QUS devices and parameters need to be determined and cross-validated widely to have a well-defined and certain use of QUS in osteoporosis clinical workflow. Despite the acknowledged current clinical limitations for QUS to be used more widely in daily routine, substantial progresses have been made and new results are promising.

Mass spectrometry and synchrotron-FTIR microspectroscopy reveal the anti-inflammatory activity of Bua Bok extracts.

INTRODUCTION: Bua Bok or Centella asiatica (CA) is an Asian vegetable with anti-inflammatory benefits. Asiaticoside, asiatic acid, madecassoside and madecassic have been characterised as major active ingredients with a wide range of pharmacological advantages. In manufacturing processes, high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LCMS) are used to routinely determine the active compounds in raw materials. OBJECTIVES: This research aims to explore anti-inflammatory properties, characterise metabolites and observe the biochemical changes of the inflammatory induced macrophages after pretreatment with the potential extracted fractions. METHODS: Bua Bok leaf extracts were prepared. Macrophages were pretreated with non-toxic fractions to determine the anti-inflammatory action. Tentative metabolites of effective fractions were identified by LC-MS. Synchrotron fourier-transform infrared (S-FTIR) microspectroscopy was utilised to observe the biochemical change of the lipopolysaccharide (LPS)-induced cells after pretreatment with potential fractions. RESULTS: Fractions of ethyl acetate, 30% and 100% ethanol highly increased the nitrile scavenging and suppressed the function of phospholipase A2 . Fractions of 70% and 100% ethanol strongly decreased nitric oxide production. The comparison of 39 chemical compounds was presented. The change of proteins was improved after pretreatment of macrophages with fraction 70% ethanol. Fraction of 100% ethanol revealed the lipid accumulation was lower than 70% ethanol and diclofenac. CONCLUSION: While the anti-inflammatory actions of 70% and 100% ethanol were similar. S-FTIR expressed they inhibited inflammatory response with the distinct features of biomolecules. The S-FTIR, LC-MS and biological assay confidently provided the efficient strategies to inform the advantage of herbal extract on cellular organisation instead of a single compound.

Physical Fitness, Adiposity, and Diets as Surrogate Measures of Bone Health in Schoolchildren: A Biochemical and Cross-Sectional Survey Analysis.

This study aimed to investigate the associations between adiposity, muscular fitness (MF), diet, sun exposure, and physical activity profiles as surrogate measures with bone health status in a sample of schoolchildren aged 8-18 yr old. A total of 250 Egyptian schoolchildren aged 8-18 yr were randomly invited to participate in these cross-sectional survey analyses. Calcaneal broadband ultrasound attenuation (c-BUA), bone mineral density (BMD), and bone formation markers (total calcium, serum bone alkaline phosphatase, and osteocalcin) were measured as markers of bone health. Adiposity profile, MF, physical activity (PA), sun exposure, Ca, and vitamin D dietary intake as related cofactors of bone health were measured by using prevalidated questionnaires and standard analytical techniques. A total of 85% (n = 213) of the study population showed normal bone health and 14.8% (n = 37) had abnormal bone health; most of them are girls (67.6%) classified according to BMD and c-BUA Z-scores into osteopenia (9.6%) and osteoporosis (5.2%). Compared with boys, higher correlations between c-BUA, bone mineral content, and BMD measures in the femoral neck, lumbar spine, whole body, and bone markers were reported in girls with lower bone mass. There was a positive significant correlation between body mass index, adiposity, sun exposure, MF, PA status, Ca and vitamin D intake, and c-BUA and BMD score analyses. These parameters were shown to be associated with about ~57.3%-88.4% of bone health characteristics of children and adolescents with osteopenia and osteoporosis. In children and adolescents, sun exposure, Ca and vitamin D diets, adiposity, PA, and changes in the levels of Ca, osteocalcin, and serum bone alkaline phosphatase were shown to be associated with bone health. Also, a significant correlation was reported between c-BUA score, dual-energy X-ray absorptiometry-BMD measures, and bone markers at clinically important bone sites of girls and boys. However, further clinical trials should be studied to consider c-BUA and bone markers as the benchmark estimates of bone mass for diagnostic purposes in young ages.

Carotenoid dietary intakes and plasma concentrations are associated with heel bone ultrasound attenuation and osteoporotic fracture risk in the European Prospective Investigation into Cancer and Nutrition (EPIC)-Norfolk cohort.

Carotenoids are found in abundance in fruit and vegetables, and may be involved in the positive association of these foods with bone health. This study aimed to explore the associations of dietary carotenoid intakes and plasma concentrations with bone density status and osteoporotic fracture risk in a European population. Cross-sectional analyses (n 14 803) of bone density status, using calcaneal broadband ultrasound attenuation (BUA) and longitudinal analyses (n 25 439) of fracture cases were conducted on data from the prospective European Prospective Investigation into Cancer and Nutrition-Norfolk cohort of middle-aged and older men and women. Health and lifestyle questionnaires were completed, and dietary nutrient intakes were derived from 7-d food diaries. Multiple regression demonstrated significant positive trends in BUA for women across quintiles of dietary α-carotene intake (P=0·029), ß-carotene intake (P=0·003), ß-cryptoxanthin intake (P=0·031), combined lutein and zeaxanthin intake (P=0·010) and lycopene intake (P=0·005). No significant trends across plasma carotenoid concentration quintiles were apparent (n 4570). The Prentice-weighted Cox regression showed no trends in fracture risk across dietary carotenoid intake quintiles (mean follow-up time 12·5 years), except for a lower risk for wrist fracture in women with higher lutein and zeaxanthin intake (P=0·022); nevertheless, inter-quintile differences in fracture risk were found for both sexes. Analysis of plasma carotenoid data (mean follow-up time 11·9 years) showed lower hip fracture risk in men across higher plasma α-carotene (P=0·026) and ß-carotene (P=0·027) quintiles. This study provides novel evidence that dietary carotenoid intake is relevant to bone health in men and women, demonstrating that associations with bone density status and fracture risk exist for dietary intake of specific carotenoids and their plasma concentrations.

Peak Bone Mass and Quantitative Ultrasound Bone Properties in Young Adulthood: A Study in the PEAK-25 Cohort of Women.

Peak bone mass is normally reached in the third decade of life. Previously, in the population-based PEAK-25 cohort (n = 1061, age 25.5 ± 0.2), we demonstrated that bone mineral density in the population-based PEAK-25 cohort is comparatively high; therefore, this study aimed to determine if the calcaneus microarchitecture mirrored this. In the process, we describe normative quantitative ultrasound (QUS) values for 25-yr-old women and the relationship between QUS values and extremes of body weight. QUS variables speed of sound (SOS), broadband ultrasound attenuation (BUA), and stiffness index were measured. Young adult values were based on the manufacturer-supplied QUS reference values. Analyses were performed in the cohort as a whole, and additionally, to understand the relationship between body weight and QUS values in young women, the variables were categorized into octiles for weight or body mass index (BMI) and the lowest and highest octiles were compared. In the cohort, SOS values, reflecting bone density, were higher (108 ± 18%), whereas BUA values, reflecting bone complexity, were lower (90 ± 14%) compared to the young adult reference population. SOS did not correlate with body weight or BMI. In the cohort, overall correlations between BUA weight, and BMI were small and positive (Pearson's r coefficients 0.261 and 0.197, respectively; p < 0.001), although in the low-weight group, r coefficients were higher (r = 0.313 and 0.268; p < 0.05). In contrast, in the high-weight group, correlation with BUA values tended to be small, negative, and nonsignificant. Correlation between QUS and dual-energy X-ray absorptiometry-measured bone mineral density was low to moderate and significant at all skeletal sites (r = 0.37-0.52). Whereas coefficients tended to be higher in the low-weight group, the reverse was apparent for the low-BMI group. In these 25-yr-old women, a comparatively high dual-energy X-ray absorptiometry-measured bone mass is offset by less complex bone structures assessed by QUS. This may have implications for later osteoporosis assessment and future fracture risk.

Bone quality of the calcaneus 5years after total knee arthroplasty.

We used non-invasive broadband ultrasound attenuation (BUA) to determine whether the pre-surgical bone quality of the calcaneus was improved 5years postoperatively, and whether the interval between total knee arthroplasty (TKA) surgeries influenced post-surgical calcaneal bone quality. All patients underwent scheduled, staged, bilateral TKA. Twenty-one patients (42 TKAs) with bilateral knee osteoarthritis were evaluated. One day before and 5years after TKA, BUA through the os calcis on the surgical side was measured. Fourteen out of 21 patients showed post-surgical improvement in BUA bilaterally. When all 42 cases were considered together there was a significant improvement in BUA 5years after surgery (P=0.042). There were no significant correlations between the changes in BUA on each side and the interval between TKA surgeries.

Geometric properties and comparative biomechanics of Homo floresiensis mandibles.

The hypodigm of Homo floresiensis from the cave of Liang Bua on Flores Island in the archipelago of Indonesia includes two mandibles (LB1/2 and LB6/1). The morphology of their symphyses and corpora has been described as sharing similarities with both australopiths and early Homo despite their Late Pleistocene age. Although detailed morphological comparisons of these mandibles with those of modern and fossil hominin taxa have been made, a functional analysis in the context of masticatory biomechanics has yet to be performed. Utilizing data on cortical bone geometry from computed tomography scans, we compare the mechanical attributes of the LB1 and LB6 mandibles with samples of modern Homo, Pan, Pongo, and Gorilla, as well as fossil samples of Paranthropus robustus, Australopithecus africanus and South African early Homo. Structural stiffness measures were derived from the geometric data to provide relative measures of mandibular corpus strength under hypothesized masticatory loading regimes. These mechanical variables were evaluated relative to bone area, mandibular length and estimates of body size to assess their functional affinities and to test the hypothesis that the Liang Bua mandibles can be described as scaled-down variants of either early hominins or modern humans. Relative to modern hominoids, the H. floresiensis material appears to be relatively strong in terms of rigidity in torsion and transverse bending, but is relatively weak under parasagittal bending. Thus, they are 'robust' relative to modern humans (and comparable with australopiths) under some loads but not others. Neither LB1 nor LB6 can be described simply as 'miniaturized' versions of modern human jaws since mandible length is more or less equivalent in Homo sapiens and H. floresiensis. The mechanical attributes of the Liang Bua mandibles are consistent with previous inferences that masticatory loads were reduced relative to australopiths but remained elevated relative to modern Homo.

More bones of Leptoptilos robustus from Flores reveal new insights into giant marabou stork paleobiology and biogeography.

Liang Bua (Flores, Indonesia) has yielded remains of a faunal community that included small-bodied and small-brained hominins, dwarf proboscideans, Komodo dragons, vultures and giant marabou storks (Leptoptilos robustus). Previous research suggested that L. robustus evolved from a smaller L eptoptilos dubius-like Middle Pleistocene ancestor and may have been flightless. However, analyses of this species' considerably expanded hypodigm (n = 43, MNI = 5), which includes 21 newly discovered bones described here for the first time, reveals that the wing bones of L. robustus were well-developed and this species was almost certainly capable of active flight. Moreover, L. robustus bones are broadly similar to Leptoptilos falconeri remains from sites in Africa and Eurasia, and its overall size range is comparable to fossils attributed to L. falconeri and similar specimens, as well as those of Leptoptilos lüi (China) and Leptoptilos titan (Java). This suggests that a Pleistocene dispersal of L. falconeri into Island Southeast Asia may have given rise to populations of giant marabou storks in this region. As L. robustus and L. titan are the most recent known representatives of these once plentiful giant marabou storks, Island Southeast Asia likely acted as a refugium for the last surviving members of this lineage.

Urinary Potential Renal Acid Load (uPRAL) among Vegans Versus Omnivores and Its Association with Bone Health in the Cross-Sectional Risks and Benefits of a Vegan Diet Study.

Both veganism and high dietary acid load are linked to unfavorable bone health. However, the specific role of dietary alkali or acid load for the bone health of vegans is so far unknown. Thus, the renal biomarker for dietary acid or alkali load, i.e., urinary potential renal acid load (uPRAL), was measured in 24 h urine samples of 34 vegans and 35 omnivores (50.7% males). Bone health was assessed via calcaneal quantitative ultrasound. Associations between uPRAL and bone health indices were examined using multivariable general linear models. Compared to omnivores, vegans had a significantly lower uPRAL (mean difference = −34.5 mEq/24 h, p < 0.0001), a lower 24 h urinary phosphate excretion (p = 0.0004), a lower 24 h urinary sulfate excretion (p = 0.01), and a higher urine pH value (p < 0.0001). Broadband ultrasound attenuation (BUA) was lower among vegans versus omnivores (p = 0.037), yet it was not associated with uPRAL irrespective of adjustments. This study confirms different acid-base profiles of vegans and omnivores, with a pronounced alkaline excess among vegans and a rather low acid load among a group of omnivores with moderate protein intake. Within this spectrum of alkaline to low acid load, no association with bone health was found.

Discordance between quantitative ultrasound and dual-energy X-ray absorptiometry in bone mineral density: The Vietnam Osteoporosis Study.

OBJECTIVES: Calcaneal quantitative ultrasound measurement (QUS) has been considered an alternative to dual-energy X-ray absorptiometry (DXA) based bone mineral density (BMD) for assessing bone health. This study sought to examine the utility of QUS as an osteoporosis screening tool by evaluating the correlation between QUS and DXA. METHODS: The study was a part of the Vietnam Osteoporosis Study that involved 1270 women and 773 men aged 18 years and older. BMD at the femoral neck, total hip and lumbar spine was measured using DXA. Osteoporosis was diagnosed based on the femoral neck T-score using World Health Organization criteria. Broadband ultrasound attenuation (BUA) at the calcaneus was measured by QUS. The concordance between BUA and BMD was analyzed by the linear regression model. RESULTS: In all individuals, BUA modestly correlated with femoral neck BMD (r = 0.35; P < 0.0001) and lumbar spine BMD (r = 0.34; P < 0.0001) in both men and women. In individuals aged 50 years and older, approximately 16% (n = 92/575) of women and 3.2% (n = 10/314) of men were diagnosed to have osteoporosis. Only 0.9% (n = 5/575) women and 1.0% (n = 3/314) men were classified as "Low BUA". The kappa coefficient of concordance between BMD and BUA classification was 0.09 (95% CI, 0.04 to 0.15) for women and 0.12 (95% CI, 0.03 to 0.22) for men. CONCLUSIONS: In this population-based study, QUS BUA modestly correlated with DXA BMD, suggesting that BUA is not a reliable method for screening of osteoporosis.

Vegan Diet and Bone Health-Results from the Cross-Sectional RBVD Study.

Scientific evidence suggests that a vegan diet might be associated with impaired bone health. Therefore, a cross-sectional study (n = 36 vegans, n = 36 omnivores) was used to investigate the associations of veganism with calcaneal quantitative ultrasound (QUS) measurements, along with the investigation of differences in the concentrations of nutrition- and bone-related biomarkers between vegans and omnivores. This study revealed lower levels in the QUS parameters in vegans compared to omnivores, e.g., broadband ultrasound attenuation (vegans: 111.8 ± 10.7 dB/MHz, omnivores: 118.0 ± 10.8 dB/MHz, p = 0.02). Vegans had lower levels of vitamin A, B2, lysine, zinc, selenoprotein P, n-3 fatty acids, urinary iodine, and calcium levels, while the concentrations of vitamin K1, folate, and glutamine were higher in vegans compared to omnivores. Applying a reduced rank regression, 12 out of the 28 biomarkers were identified to contribute most to bone health, i.e., lysine, urinary iodine, thyroid-stimulating hormone, selenoprotein P, vitamin A, leucine, α-klotho, n-3 fatty acids, urinary calcium/magnesium, vitamin B6, and FGF23. All QUS parameters increased across the tertiles of the pattern score. The study provides evidence of lower bone health in vegans compared to omnivores, additionally revealing a combination of nutrition-related biomarkers, which may contribute to bone health. Further studies are needed to confirm these findings.

The quantitative ultrasound method for assessing low bone mass in women with anorexia nervosa.

This study investigated the potential role of quantitative ultrasound (QUS) to assess low bone mass in anorexia nervosa patients (AN). Bone parameters from QUS and DXA were positively correlated and significantly reduced in AN compared with controls, suggesting that QUS is a pertinent technique to assess low bone mass in these patients. PURPOSE: The aim of this study was to investigate the potential role of an alternative technique, quantitative ultrasound (QUS), to assess low bone mass in patients with anorexia nervosa (AN). METHODS: Two hundred seven young women (134 patients with AN and 73 healthy controls) with ages ranging from 14.4 to 38.4 years participated in this observational cross-sectional study. Bone mass was concomitantly evaluated by DXA to determine areal bone mineral density (aBMD; g/cm2) at hip, lumbar spine, and radius and by QUS to determine broadband ultrasound attenuation (BUA; dB/MHz) at the heel. RESULTS: BUA (66.5 ± 4.6 dB/MHz vs 61.0 ± 5.0 dB/MHz) and aBMD at the hip (0.916 ± 0.013 g/cm2 vs 0.806 ± 0.010 g/cm2), lumbar spine (0.966 ± 0.012 g/cm2 vs 0.886 ± 0.010 g/cm2), and radius (0.545 ± 0.005 g/cm2 vs 0.526 ± 0.04 g/cm2) were significantly decreased (p < 0.01) in patients with AN compared with controls. When patient and control data were pooled, BUA was significantly correlated with aBMD at the hip (r = 0.60, p < 0.001), lumbar spine (r = 0.48, p < 0.001), and radius (r = 0.40, p<0.001). In patients with AN, BUA and aBMD were mainly and positively correlated with weight, lean tissue mass, body mass index (BMI), and minimal BMI life and negatively with the duration of both disease and amenorrhea. Better concordance between the two techniques was obtained when absolute BUA and aBMD values were used according to the WHO T score classification. CONCLUSION: BUA measurement at the heel by QUS appears to be a pertinent nonionizing technique to assess low bone mass in patients with AN.

Risk factors for progression of ossification of the posterior longitudinal ligament in asymptomatic subjects.

OBJECTIVE: The incidence and risk factors for the progression of ossification of the posterior longitudinal ligament (OPLL) have been previously reported in surgically and nonsurgically treated symptomatic patients. However, the correlates of OPLL progression in asymptomatic subjects with OPLL are not well characterized. This study aimed to clarify the incidence and risk factors for OPLL progression in asymptomatic subjects based on whole-body CT. METHODS: The authors retrospectively reviewed 2585 healthy subjects who underwent whole-body CT at a single health center from September 2007 to December 2011. This study included asymptomatic subjects with OPLL who underwent CT scans twice with an interval of at least 5 years. Progression of OPLL was assessed based on initial and final CT scan. Subjects were divided into two groups: nonprogression (OPLL-NP) and progression (OPLL-P) groups. Clinical characteristics, bone mineral density status, OPLL types, and OPLL involvement of multiple vertebral levels between the two groups were compared. Risk factors for progression of OPLL were identified by logistic regression analysis after propensity score adjustment. RESULTS: Of the 109 subjects with OPLL (91 men and 18 women), 20 (18.3%) exhibited OPLL progression (OPLL-P group). Subjects in the OPLL-P group were significantly younger (p = 0.031), had higher prevalence of multilevel OPLL involvement (p = 0.041) and continuous type of OPLL (p = 0.015), and had higher uric acid (UA) levels (p = 0.004) at the time of initial CT examination compared to the OPLL-NP group. Younger age (adjusted odds ratio [aOR] 0.95, 95% CI 0.90-0.99), OPLL involvement of multiple vertebral levels (aOR 2.88, 95% CI 1.06-7.83), continuous type of OPLL (aOR 4.21, 95% CI 1.35-13.10), and higher UA levels (aOR 2.09, 95% CI 1.24-3.53) were significant risk factors for OPLL progression. CONCLUSIONS: Younger age, OPLL involvement of multiple vertebral levels, continuous type of OPLL, and higher UA levels are significant risk factors for OPLL progression in asymptomatic subjects.

Ethnic Variations in Serum 25(OH)D Levels and Bone Ultrasound Attenuation Measurements in Blacks and Whites.

Vitamin D deficiency is more common in Blacks, yet Blacks have lower prevalence of bone fragility fractures or osteoporosis than Whites. Broadband ultrasound attenuation (BUA) has been used to explore the association between serum 25(OH)D levels and bone quality in White and non-white populations. We investigated serum 25(OH)D status with corresponding BUA measurements assessed cross sectionally in a cohort of 232 Blacks and 260 Whites, aged 30-95 years who were part of the calibration study of the large Adventist Health Study-2 (AHS-2). At the calibration clinics, calcaneal BUA was measured and blood drawn for serum 25(OH)D assessment. In multivariable analyses, BUA was negatively associated with age (ß-coefficient = -0.38; p < 0.0001) and positively associated with body mass index (BMI) (p (trend) < 0.0001) and positively, but non-significantly, associated with serum 25(OH)D levels. Also, as expected, females had lower BUA (ß-coefficient = -5.19; p < 0.05) and Blacks had higher BUA (ß-coefficient = 4.26; p < 0.05). Gender and race modified the relationship of serum 25(OH)D on BUA with a positive association in males (p (trend) ≤ 0.05), but no significant association in females after also controlling for menopausal status and hormone therapy. After also controlling for serum 25(OH)D levels, Black males had higher BUA than White men, but such differences were not found among the females. When stratifying on race, a positive association between serum 25(OH)D levels and BUA (p (trend) ≤ 0.05) was found in Blacks, but not among Whites. Further studies are needed to understand how racial/ethnic differences in serum 25(OH)D levels influence bone health.

Attempt at standardization of bone quantitative ultrasound in Japan.

Dual X-ray absorptiometry (DXA) is used to diagnose osteoporosis. On the other hand, quantitative ultrasound (QUS) is widely used to assess bone density as part of medical screening as it is relatively inexpensive and easy to perform. Current QUS devices do not share precise ultrasound-related parameters, such as frequency, waveform, beam pattern, transient response, definition of propagation time, definition of degree of attenuation, and precise measurement site, resulting in different measurements across models. The Japan Osteoporosis Society established a QUS Standardization Committee in 2007 to investigate standardization of speed of sound (SOS) and broadband ultrasonic attenuation (BUA) measurements to resolve this issue. The committee came up with a formula to convert SOS and BUA values yielded by each model available in Japan. This has made it possible to convert QUS measurements from different models into standardized values, greatly improving the effectiveness of QUS measurements.

Sex hormones and quantitative ultrasound parameters at the heel in men and women from the general population.

PURPOSE/INTRODUCTION: The present study investigates potential associations between liquid chromatography-mass spectrometry (LC-MS) measured sex hormones, dehydroepiandrosterone sulphate, sex hormone-binding globulin (SHBG) and bone ultrasound parameters at the heel in men and women from the general population. METHODS: Data from 502 women and 425 men from the population-based Study of Health in Pomerania (SHIP-TREND) were used. Cross-sectional associations of sex hormones including testosterone (TT), calculated free testosterone (FT), dehydroepiandrosterone sulphate (DHEAS), androstenedione (ASD), estrone (E1) and SHBG with quantitative ultrasound (QUS) parameters at the heel, including broadband ultrasound attenuation (BUA), speed of sound (SOS) and stiffness index (SI) were examined by analysis of variance (ANOVA) and multivariable quantile regression models. RESULTS: Multivariable regression analysis showed a sex-specific inverse association of DHEAS with SI in men (Beta per SI unit = - 3.08, standard error (SE) = 0.88), but not in women (Beta = - 0.01, SE = 2.09). Furthermore, FT was positively associated with BUA in men (Beta per BUA unit = 29.0, SE = 10.1). None of the other sex hormones (ASD, E1) or SHBG was associated with QUS parameters after multivariable adjustment. CONCLUSIONS: This cross-sectional population-based study revealed independent associations of DHEAS and FT with QUS parameters in men, suggesting a potential influence on male bone metabolism. The predictive role of DHEAS and FT as a marker for osteoporosis in men warrants further investigation in clinical trials and large-scale observational studies.

Adequacy and verifiability of pharmaceutical mixtures and dose units by variographic analysis (Theory of Sampling) - A call for a regulatory paradigm shift.

In spite of intense efforts in the last 20 years, the current state of affairs regarding evaluation of adequacy of pharmaceutical mixing is at an impressive standstill, characterized by two draft guidances, one withdrawn, and the other never approved. We here analyze the regulatory, scientific and technological situation and suggest a radical, but logical approach calling for a paradigm shift regarding sampling of pharmaceutical blends. In synergy with QbD/PAT efforts, blend uniformity testing should only be performed with properly designed sampling that can guarantee representativity-in contrast to the current deficient thief sampling. This is necessary for suitable in-process specifications and dosage units meeting desired specifications. The present exposé shows how process sampling based on the Theory of Sampling (TOS) constitutes a new asset for regulatory compliance, providing procedures that suppress hitherto adverse sampling errors. We identify that the optimal sampling location is after emptying the blender, guaranteeing complete characterisation of the residual heterogeneity. TOS includes variographic analysis that decomposes the effective total sampling and analysis error (TSE+TAE) from the variability of the manufacturing process itself. This approach provides reliable in-process characterization allowing independent approval or rejection by the Quality Control unit. The science-based sampling principles presented here will facilitate full control of blending processes, including whether post-blending segregation influences the material stream that reaches the tabletting feed-frame.

Experimental and computer simulation validation of ultrasound phase interference created by lateral inhomogeneity of transit time in replica bone: marrow composite models.

The measurement of broadband ultrasound attenuation in cancellous bone for the assessment of osteoporosis follows a parabolic-type dependence with bone volume fraction, having minima values corresponding to both entire bone and entire marrow. Langton has recently proposed that the primary attenuation mechanism is phase interference due to variations in propagation transit time through the test sample as detected over the phase-sensitive surface of the receive ultrasound transducer. This fundamentally simple concept assumes that the propagation may be considered as an array of parallel 'sonic rays'. The transit time of each ray is defined by the proportion of bone and marrow propagated, being a minimum (t(min)) solely through bone and a maximum (t(max)) solely through marrow, from which a transit time spectrum, may be defined describing the proportion of sonic rays having a particular transit time. The aim of this study was to test the hypothesis that there is a dependence of phase interference upon the lateral inhomogeneity of transit time by comparing experimental measurements and computer simulation predictions of ultrasound propagation through a range of relatively simplistic solid:liquid models. From qualitative and quantitative comparison of the experimental and computer simulation results, there is an extremely high degree of agreement of 94.2%-99.0% between the two approaches. This combined experimental and computer simulation study has successfully demonstrated that lateral inhomogeneity of transit time has significant potential for phase interference to occur if a phase-sensitive receive ultrasound transducer is implemented as in most commercial ultrasound bone analysis devices.