Non-Iterative Multiscale Estimation for Spatial Autoregressive Geographically Weighted Regression Models.

Multiscale estimation for geographically weighted regression (GWR) and the related models has attracted much attention due to their superiority. This kind of estimation method will not only improve the accuracy of the coefficient estimators but also reveal the underlying spatial scale of each explanatory variable. However, most of the existing multiscale estimation approaches are backfitting-based iterative procedures that are very time-consuming. To alleviate the computation complexity, we propose in this paper a non-iterative multiscale estimation method and its simplified scenario for spatial autoregressive geographically weighted regression (SARGWR) models, a kind of important GWR-related model that simultaneously takes into account spatial autocorrelation in the response variable and spatial heterogeneity in the regression relationship. In the proposed multiscale estimation methods, the two-stage least-squares (2SLS) based GWR and the local-linear GWR estimators of the regression coefficients with a shrunk bandwidth size are respectively taken to be the initial estimators to obtain the final multiscale estimators of the coefficients without iteration. A simulation study is conducted to assess the performance of the proposed multiscale estimation methods, and the results show that the proposed methods are much more efficient than the backfitting-based estimation procedure. In addition, the proposed methods can also yield accurate coefficient estimators and such variable-specific optimal bandwidth sizes that correctly reflect the underlying spatial scales of the explanatory variables. A real-life example is further provided to demonstrate the applicability of the proposed multiscale estimation methods.

Transcriptional profiling of uterine leiomyoma rats treated by a traditional herb pair, Curcumae rhizoma and Sparganii rhizoma.

The aim of this study was to elucidate the concise effects of a traditional herb pair, Curcumae rhizoma-Sparganii rhizoma (CRSR), on uterine leiomyoma (UL) by analyzing transcriptional profiling. The UL rat model was made by intramuscular injection of progesterone and gavage administration of diethylstilbestrol. From 11 weeks of the establishment of the model, rats of the UL+CRSR group were gavaged daily with CRSR (6.67 g/kg). The serum concentrations of progesterone (P) and estradiol (E2) were determined by radioimmunoassay, the uterine index was measured by caliper measurement, and the pathological status was observed by hematoxylin and eosin stain. Gene expression profiling was checked by NimbleGen Rat Gene Expression Microarrays. The results indicated that the uterine mass of UL+CRSR rats was significantly shrunk and serum P and E2 levels significantly reduced compared to UL animals and nearly to the level of normal rats. Results of microarrays displayed the extensive inhibition of CRSR upon the expression of proliferation and deposition of extracellular matrix (ECM)-related genes, and significantly regulated a wide range of metabolism disorders. Furthermore, CRSR extensively regulated key pathways of the UL process, such as MAPK, PPAR, Notch, and TGF-ß/Smad. Regulation of the crucial pathways for the UL process and ECM metabolism may be the underlying mechanisms of CRSR treatment. Further studies will provide clear clues for effectively treating UL with CRSR.

Transcriptional profiling of uterine leiomyoma rats treated by a traditional herb pair, Curcumae rhizoma and Sparganii rhizoma

The aim of this study was to elucidate the concise effects of a traditional herb pair, Curcumae rhizoma-Sparganii rhizoma (CRSR), on uterine leiomyoma (UL) by analyzing transcriptional profiling. The UL rat model was made by intramuscular injection of progesterone and gavage administration of diethylstilbestrol. From 11 weeks of the establishment of the model, rats of the UL+CRSR group were gavaged daily with CRSR (6.67 g/kg). The serum concentrations of progesterone (P) and estradiol (E2) were determined by radioimmunoassay, the uterine index was measured by caliper measurement, and the pathological status was observed by hematoxylin and eosin stain. Gene expression profiling was checked by NimbleGen Rat Gene Expression Microarrays. The results indicated that the uterine mass of UL+CRSR rats was significantly shrunk and serum P and E2 levels significantly reduced compared to UL animals and nearly to the level of normal rats. Results of microarrays displayed the extensive inhibition of CRSR upon the expression of proliferation and deposition of extracellular matrix (ECM)-related genes, and significantly regulated a wide range of metabolism disorders. Furthermore, CRSR extensively regulated key pathways of the UL process, such as MAPK, PPAR, Notch, and TGF-β/Smad. Regulation of the crucial pathways for the UL process and ECM metabolism may be the underlying mechanisms of CRSR treatment. Further studies will provide clear clues for effectively treating UL with CRSR.

[Association of angiotensin II receptor type 1 gene single nucleotide polymorphism with Chinese essential hypertension complicated with coronary heart disease].

OBJECTIVE: To identify the genetic variants of angiotensin II type 1 receptor (AT1) gene in a population of Han ethnicity in east China and to determine whether the AT1 gene polymorphisms are associated with essential hypertension (EH) and coronary heart disease (CHD). METHODS: The detection of single nucleotide polymorphisms (SNPs) was performed in 20 subjects by a direct DNA sequencing. All 213 EH patients, 171 patients of EH with CHD and 200 controls were genotyped by three detected SNPs. RESULTS: Eight positive SNPs were detected in the promoter, exon and 3' untranslated region (3'UTR) of AT1 gene. A case-control study by using a frequent SNP (A-153G) in the promoter region, showed a significant increase in allele frequency of G-153 in the subjects of EH complicated with CHD (17.8% vs 11.5% for normal controls, P < 0.05). The SNP A1166C, which has been widely studied, manifested no difference in the three groups. CONCLUSION: A polymorphism in the promoter region (A-153G) of AT1 gene might be involved in the development of EH and CHD in Han ethnicity population in east China.