Although 17β-estradiol (E2) deficiency has been linked to the development
of osteoarthritis (OA) in middle-aged women, there are few studies relating other
estrogens and estrogen metabolites (EMs) to this condition. We developed a
high-performance liquid chromatography-electrospray ionization-tandem mass
spectrometry (HPLC-ESI-MS/MS) method to measure the levels of six EMs (i.e., estrone,
E2, estriol, 2-hydroxyestrone, 2-hydroxyestradiol, and
16a-hydroxyestrone) in healthy pre- and postmenopausal women and women with OA. This
method had a precision ranging from 1.1 to 3.1% and a detection limit ranging from 10
to 15 pg. Compared to healthy women, serum-free E2 was lower in the luteal
and postmenopausal phases in women with OA, and total serum E2 was lower
in postmenopausal women with OA. Moreover, compared to healthy women, total serum
2-hydroxyestradiol was higher in postmenopausal women with OA and total serum
2-hydroxyestrone was lower in both the luteal and follicular phases in women with OA.
In conclusion, our HPLC-ESI-MS/MS method allowed the measurement of multiple
biochemical targets in a single assay, and, given its increased cost-effectiveness,
simplicity, and speed relative to previous methods, this method is suitable for
clinical studies.
Most studies on peripheral nerve injury have focused on repair at the site of injury, but very few have examined the effects of repair strategies on the more proximal neuronal cell bodies. In this study, an approximately 10-mm-long nerve segment from the ischial tuberosity in the rat was transected and its proximal and distal ends were inverted and sutured. The spinal cord was subjected to pulsed electrical stimulation at T10 and L3, at a current of 6.5 mA and a stimulation frequency of 15 Hz, 15 minutes per session, twice a day for 56 days. After pulsed electrical stimulation, the number of neurons in the dorsal root ganglion and anterior horn was increased in rats with sciatic nerve injury. The number of myelinated nerve fibers was increased in the sciatic nerve. The ultrastructure of neurons in the dorsal root ganglion and spinal cord was noticeably improved. Conduction velocity of the sciatic nerve was also increased. These results show that pulsed electrical stimulation protects sensory neurons in the dorsal root ganglia as well as motor neurons in the anterior horn of the spinal cord after peripheral nerve injury, and that it promotes the regeneration of peripheral nerve fibers.
US and MRI should remain the first line for the diagnosis of breast cancer. Both MRI and FDG-PET/CT could accurately diagnose the primary breast cancer and stage the axilla lymph nodes, but further large population study is needed.
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