Longitudinal changes in bone mineral density of healthy elderly women in southern Taiwan.

OBJECTIVE: Longitudinal data on bone decline in ethnic Chinese elderly are sparse, especially in healthy, aged women. This study reviews the longitudinal change in bone mineral density (BMD) at the femoral neck, great trochanter, and Ward's triangle in healthy elderly Taiwanese women. MATERIALS AND METHODS: A prospective cohort study was conducted, with 1500 women aged ≥ 61 years. Fifty-four were eligible for hip evaluation and 52 underwent examination for hip BMD. Two years later, 50 women had a follow-up BMD examination. Linear regression was performed between age and bone density. The paired t test was used for BMD changes between examinations. RESULTS: In the initial study, there was a negative relationship between BMD and age using liner regression at all three sites (p < 0.05). Two years later, there was a significant decrease in BMD at all three sites (p < 0.01). In terms of age cohorts, both age groups showed a significant decrease in BMD at the three sites studied (p < 0.01). There was a peak loss of BMD as high as 2.74% annually at the Ward's triangle in those aged 61-70 years. CONCLUSION: Our findings indicate that BMD is negatively correlated to aging in the healthy female. The loss of BMD at the Ward's triangle in those aged 61-70 years is faster than at other sites. Attention should be given to bone loss in ethnic Chinese females because their bone loss is more severe than that of Caucasians.

One-step microwave-assisted headspace solid-phase microextraction for the rapid determination of synthetic polycyclic musks in oyster by gas chromatography-mass spectrometry.

A rapid, simple and solvent-free procedure was developed for the determination of synthetic polycyclic musks in oyster samples by using one-step microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) and gas chromatography-mass spectrometry (GC-MS). Two commonly used synthetic polycyclic musks, galaxolide (HHCB) and tonalide (AHTN), were selected in the method development and validation. The parameters (microwave irradiation power, extraction time, amount of water added, pH value and addition of NaCl) affecting the extraction efficiency of analytes from oyster slurry were systematically investigated and optimised. The best extraction conditions were achieved when the oyster tissue mixed with 10-mL deionised water (containing 3g of NaCl in a 40-mL sample-vial) was microwave irradiated at 80 W for 5 min. The limit of quantification (LOQ) was 0.1 ng/g in 5-g of wet tissue. The good precision and accuracy of one-step MA-HS-SPME coupled with GC-MS for the determination of trace level of AHTN in oyster samples was also demonstrated.

Microwave-assisted headspace solid-phase microextraction for the rapid determination of organophosphate esters in aqueous samples by gas chromatography-mass spectrometry.

The rapid and solvent-free determination of organophosphate esters (OPEs) in aqueous samples via one-step microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS) analysis is described. Tri-n-butyl phosphate (TnBP) and tris-(2-ethylhexyl) phosphate (TEHP) were selected as model compounds for the method of development and validation. The effects of various extraction parameters for the quantitative extraction of these analytes by MA-HS-SPME were systematically investigated and optimized. The analytes, in a 20 mL water sample (in a 40 mL sample bottle containing 2g of NaCl, pH 3.0), were efficiently extracted by a polydimethylsiloxane-divinylbenzene (PDMS-DVB) fiber placed in the headspace when the system was microwave irradiated at 140 W for 5 min. The limits of quantification (LOQs) for TnBP and TEHP were 0.5 and 4 ng/L, respectively. Using the standard addition method, MA-HS-SPME coupled with GC-MS was utilized to determine selected OPEs in surface water and wastewater treatment plants (WWTP) influent/effluent samples. Preliminary results show that TnBP was commonly detected OPEs in these aqueous samples, the correlation coefficients (r(2)) of the standard addition curves were greater than 0.9822, indicating that the developed method appears to be a good alternative technique for analyzing OPEs in aqueous samples.

Fast determination of synthetic polycyclic musks in sewage sludge and sediments by microwave-assisted headspace solid-phase microextraction and gas chromatography-mass spectrometry.

One-step in situ microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) followed by gas chromatography-mass spectrometry (GC-MS) analysis is presented as a fast and solvent-free technique to determine synthetic polycyclic musks in sewage sludge and sediment samples. Six synthetic polycyclic musks (galaxolide (HHCB), tonalide (AHTN), celestolide (ADBI), traseolide (ATII), cashmeran (DPMI) and phantolide (AHMI)) were selected in the method development and validation. The effects of extraction parameters for the quantitative extraction of these analytes by one-step MA-HS-SPME were systematically investigated. The dewatered solid sample mixed with 20-mL deionized water (containing 3 g of NaCl in a 40-mL sample-vial) was efficiently extracted by a polydimethylsiloxane-divinylbenzene (PDMS-DVB) fiber placed in the headspace when the extraction slurry was microwave irradiated at 80 W for 5 min. The limits of detection (LODs) ranged from 0.04 to 0.1 ng/g, and the limits of quantification (LOQs) ranged from 0.1 to 0.3 ng/g (fresh weight). A preliminary analysis of sludge and sediment samples revealed that HHCB and AHTN were the two most commonly detected synthetic polycyclic musks; using a standard addition method, their total concentrations were determined to range from 0.3 to 10.9 ng/g (fresh weight) with relative standard deviation (RSD) ranging from 4% to 10%.

Longitudinal changes in bone mineral density of healthy elderly men in southern Taiwan.

BACKGROUND/PURPOSE: Longitudinal data on bone decline for Chinese elderly people are sparse, especially for the healthy aged male. We report the longitudinal change in bone mineral density (BMD) at the femoral neck, great trochanter and Ward's triangle in healthy older Taiwanese men. METHODS: A prospective cohort study was conducted. We screened 1500 subjects aged > or = 65 years. One hundred and seventy men were eligible for hip evaluation, and 167 had hip BMD measured. Two years later, 142 men completed follow-up BMD measurement. Linear regression was performed between aging and bone loss. Paired t test was used to determine changes in BMD between the intervals. RESULTS: In the initial study, subjects showed significant bone loss through aging by linear regression at all three sites (p < 0.001). Two years later, there was a significant decrease in BMD at all three sites (p < 0.001). For the age cohort, all the age groups showed a significant decrease in BMD at the three study sites (p < 0.05), except those aged > or = 75 years at Ward's triangle (p = 0.667) and the great trochanter (p = 0.1). There was a peak loss of BMD in men aged 65-69 years, as high as 5.57% annually at Ward's triangle. CONCLUSION: BMD was negatively related to aging in healthy men. The loss of BMD in the 65-69 years age group was faster at Ward's triangle than at other sites. Bone loss in Chinese men is of concern because it is greater than in Caucasian men.