[Regulatory mechanism of hormones of the pituitary-target gland axes in kidney-Yang deficiency based on a support vector machine model].

OBJECTIVE: To study the development mechanism of kidney-Yang deficiency through the establishment of support vector machine models of relevant hormones of the pituitary-target gland axes in rats with kidney-Yang deficiency syndrome. METHODS: The kidney-Yang deficiency rat model was created by intramuscular injection of hydrocortisone, and contents of the hormones of the pituitary-thyroid axis: thyroid stimulating hormone (TSH), 3,3',5-triiodothyronine (T3) and thyroxine (T4); hormones of the pituitary-adrenal gland axis: adrenocorticotropic hormone (ACTH) and cortisol (CORT); and hormones of the pituitary-gonadal axis: luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone (T), were determined in the early, middle, and advanced stages. Ten support vector regression (SVR) models of the hormones were established to analyze the mutual relationships among the hormones of the three axes. RESULTS: The feedback control action of the pituitary-adrenal axis began to lose efficacy from the middle stage of kidney-Yang deficiency. The contents all hormones of the three pituitary-target gland axes decreased in the advanced stage. Relative errors of the jackknife test of the SVR models all were less than 10%. CONCLUSION: Imbalances in mutual regulation among the hormones of the pituitary-target gland axes, especially loss of effectiveness of the pituitary-adrenal axis, is one pathogenesis of kidney-Yang deficiency. The SVR model can accurately reflect the complicated non-linear relationships among pituitary-target gland axes in rats with of kidney-Yang deficiency.

A radiolabeled nonapeptide probe targeting PC-3 cells and bone metastases of prostate cancer in mice.

Previous investigations showed that interleukin-11 (IL-11) and the IL-11 receptor (IL-11R) are correlated with regulation of tumor progression and may play significant roles in bone metastases. The nonapeptide structure c(CGRRAGGSC) is a phage-display-selected IL-11 mimic that binds to IL-11R. The aim of this study was to synthesize radiolabeled c(CGRRAGGSC) and to investigate the possible interaction between this radioactive probe and an IL-11R-positive bone metastasis model of PC-3 prostate cancer. The molecular probe (99m)Tc-DTPA-c(CGRRAGGSC) was radiolabeled with (99m)Tc using the diethylenetriaminepentaacetic acid (DTPA) chelate. Counterstaining was performed with LSS670, a near-infrared dye. The binding sites of the molecular probe in PC-3 cells were observed under a fluorescence microscope. The binding characteristics of the labeled probe were analyzed using radioreceptor analysis. Single photon emission tomography imaging and biodistribution of the probe were investigated using xenografts of PC-3 cells into tibias of nude mice. The labeled product, (99m) Tc-DTPA-c(CGRRAGGSC), was obtained with high labeling efficiency, high radiochemical purity and good stability. The molecular probe was combined with the PC-3 cell membrane and cytoplasm through fluorescence tracing. In the saturation and competitive inhibition experiments performed in vitro, the K(d) value was 0.32 ± 0.02 n m and the B(max) value was 754 ± 34 fmol mg(-1) pro. The probe exhibited a high tumor uptake in vivo. The radioactive molecular probe (99m) Tc-DTPA-c(CGRRAGGSC) may be used as a specific molecular imaging agent for detecting IL-11R overexpression in tumors and bone metastasis, such as prostate cancers.

Construction of a cDNA fragment library from SH-SY5Y cells using restriction display PCR.

A complementary DNA (cDNA) fragment library from SH-SY5Y cells is constructed using a restriction display polymerase chain reaction (RD-PCR) technique. Messenger RNA (mRNA) is extracted from SH-SY5Y cells and single-strand cDNA synthesised using an anchored oligo primer (dT18). The second strand is produced by nick translation. The double strands are cleaved with the restriction enzyme Sau3AI and the fragments ligated with universal linker. The products are amplified with universal primers and selected primers, ligated into the pMDI8-T vector, and then sequenced. The library constructed contained 136 subgroups, each comprising seven to 12 cDNA fragments. RD-PCR proved a simple, effective way to construct a cDNA library, and this will contribute to the investigation of gene expression in the neuron in future microarray studies.