Age-associated changes in bone ultrasonometry of the os calcis

Organ-on-a-Chip Systems for Women's Health Applications

Biomedical research, for a long time, has paid little attention to the influence of sex in many areas of study, ranging from molecular and cellular biology to animal models and clinical studies on human subjects. Many studies solely rely on male cells/tissues/animals/humans, although there are profound differences in male and female physiology, which can significantly impact disease mechanisms, toxicity of compounds, and efficacy of pharmaceuticals. In vitro systems have been traditionally very limited in their capacity to recapitulate female-specific physiology and anatomy such as dynamic sex-hormone levels and the complex interdependencies of female reproductive tract organs. However, the advent of microphysiological organ-on-a-chip systems, which attempt to recreate the 3D structure and function of human organs, now gives researchers the opportunity to integrate cells and tissues from a variety of individuals. Moreover, adding a dynamic flow environment allows mimicking endocrine signaling during the menstrual cycle and pregnancy, as well as providing a controlled microfluidic environment for pharmacokinetic modeling. This review gives an introduction into preclinical and clinical research on women's health and discusses where organ-on-a-chip systems are already utilized or have the potential to deliver new insights and enable entirely new types of studies.

The influence of chemotherapy on bone mineral density, quantitative ultrasonometry and bone turnover in pre-menopausal women with breast cancer

INTRODUCTION

The effects of doxorubicin/cyclophosphamide (A/C; 6 cycles) chemotherapy on bone mineral density (BMD), quantitative ultrasonography (QUS) and bone turnover markers in pre-menopausal women with oestrogen receptor-negative breast cancer (BC) were compared with age-matched controls.

METHODS

Among 106 women (BC=53, controls=53), BMD (spine and hip), QUS (calcaneus and phalanges) and bone marker levels were measured at baseline, 6 and 12 months. Correlations between parameters were determined by Spearman's rho.

RESULTS

All BC patients became amenorrhoeic after chemotherapy and remained so for the duration of treatment. BC patients had significant bone loss at all sites (P.005) and significant increases in bone turnover (P.05). There were significant correlations between BMD, QUS and bone markers (P.05).

CONCLUSIONS

Results confirm A/C's deleterious influence on bone health in pre-menopausal women with BC and established QUS's utility for monitoring bone effects. Large-scale longitudinal studies are needed to further understand and prevent bone changes following chemotherapy.

Quantitative Ultrasonography of Calcaneal Bone Mass and Its Relationship to Calcium Consumption Among Impoverished Hispanic Women

Perimenopausal Hispanic women need to be able to build and sustain peak bone mass, but this may be affected by their low socioeconomic status. This feasibility research study provided descriptive information on the relationship between calcium consumption and bone mass measured with sonography at the calcaneus. Little research exists to examine bone health with this specific age or ethnic group of women. This research found a strong positive correlation between the amount of self-reported calcium food consumed and the bone stiffness index recorded using quantitative sonography. The translational impact of this project will inform the development of culturally relevant patient education for Hispanic women of low socioeconomic status to encourage the development of peak bone mass.

Decreased bone mineral density in patients with neurofibromatosis 1

Neurofibromatosis 1 (NF1) is one of the most common autosomal dominant diseases. Although there is a considerable variability in clinical expression, NF1 is almost fully penetrant in adult patients and may be associated with a variety of skeletal anomalies. Spinal deformities are the most common skeletal manifestation, with an incidence estimated from 10-25% in various studies. Some NF1 patients have a dystrophic form of scoliosis, which is characterized by early age at onset and rapid progression. Complications have been reported during spinal instrumentation of dystrophic curves due to soft, non-resistant vertebral bony tissue, suggesting that an alteration of bone quality may occur in NF1 patients. Recent studies have suggested that decreased bone mineral density (BMD) may occur among patients with NF1. We performed a cross-sectional study on 104 adults with NF1, using quantitative ultrasonometry (QUS) to investigate whether decreased BMD is a general phenomenon in NF1 patients. The data reveal that BMD, as measured by age- and gender- adjusted Z-scores, is significantly lower in NF1 patients than in the normal reference population. The decrease in BMD appears to be even more marked among NF1 patients with scoliosis that requires surgical treatment. The findings indicate that NF1 produces a generalized alteration of bone in addition to the focal osseous dysplasias of the vertebrae, tibia, and sphenoid wing that characterize this condition. The pathological mechanism underlying these bony changes remains to be elucidated.

Limited diagnostic agreement of quantitative sonography of the radius and phalanges with dual-energy x-ray absorptiometry of the spine, femur, and radius for diagnosis of osteoporosis

OBJECTIVE

The aim of our study was to evaluate the diagnostic agreement of quantitative sonography of the radius and proximal phalanx and dual-energy X-ray absorptiometry (DXA) of the radius, lumbar spine, and femoral neck for the detection of osteoporosis.

MATERIALS AND METHODS

In 95 women (mean age, 53 +/- 13 years) and 26 men (mean age, 53 +/- 13 years), DXA measurements of the lumbar spine (posterior-anterior, L1-L4) and the femoral neck, as well as quantitative sonography of the radius and proximal phalanx of the third finger were obtained. The percentage of patients below a given threshold was calculated for each imaging technique. A T score of less than -2.5 indicated presence of osteoporosis. Diagnostic agreement in identifying individuals with osteoporosis was assessed using kappa scores.

RESULTS

Between 14% and 22% of the patients were classified as osteoporotic after DXA of the various regions of interest of the radius, 31% after DXA of the spine, 43% after DXA of the femoral neck, 32% after quantitative sonography of the distal radius, and 34% after quantitative sonography of the phalanx of the third finger. Correlation coefficients between T values for quantitative sonography and those for DXA varied between not significant and 0.54 at the different regions. Kappa analysis showed the diagnostic agreement among quantitative sonography and DXA to be fair to moderate (kappa = 0.38-0.48). The highest agreement was between quantitative sonography of the proximal phalanx of the third finger and DXA of the total radius (kappa 0.48; p < 0.05).

CONCLUSION

Considerable diagnostic disagreement exists between quantitative sonography and DXA of the forearm, as is true for most quantitative techniques in the assessment of skeletal status. The lack of correlation makes quantitative sonography impractical for routine diagnostic use but might characterize different parameters related to bone quality.

Quantitative ultrasound (QUS) of bone in the management of postmenopausal women

OBJECTIVES

Postmenopausal osteoporosis is becoming a major problem for healthcare institutions as it has a growing social and economic impact. The incidence of osteoporotic fractures is constantly increasing due to the increase in life expectancy. The gynaecologist plays an important role in establishing a "biological zero" in each perimenopausal patient, and controlling the rate of bone loss during postmenopausal period.

RESULTS

Dual energy X-ray absorptiometry (DXA) has been widely used for the diagnosis and management of osteoporosis and represents a strong risk factor for fractures, but it presents several limitations with regards to diagnosis, treatment follow-up and differential diagnosis of secondary osteoporosis. In these last years quantitative ultrasound (QUS) technique has been introduced for the evaluation of bone status in postmenopausal women and several in vitro and clinical studies have demonstrated the reliability of the examination in terms of: reproducibility, evaluation of fracture risk, treatment follow-up, differential diagnosis. QUS has proven to be equally capable in the prediction of future osteoporosis related fractures in comparison to DXA. Large-scale cross-sectional and longitudinal studies have demonstrated the applicability of QUS in screening the female population during the climacteric period. QUS technique seems to be very efficient in identifying "fast losers", identifying subjects at risk for osteoporosis requiring second-level investigation (DXA, X-ray), diagnosing secondary osteoporosis.

CONCLUSION

If QUS is used in a systematic and rational manner in clinical practice, it is a valid technique for the prevention of osteoporosis in postmenopausal women.