ABSTRACT
Objective To look for a tissue paraffin embedding method that can replace xylene transparent agent. Methods The mixture of N-butanol and turpentine was used to replace the role of anhydrous ethanol and xylene in the process of conventional paraffin embedding. The brain, kidney, stomach, liver and duodenum of multiple cerebral infarction model rats were embedded in paraffin. Finally, the new dehydration procedure was evaluated according to the effect of paraffin section, HE staining and immunohistochemical result . Results The mixture of N-butanol and turpentine could replace not only the dehydration effect of anhydrous ethanol but also the transparency effect of xylene in the conventional paraffin embedding process. The tissue sections treated with the mixture of N-butanol and turpentine were smooth, and the tissue did not become brittle or hard; After HE staining, the nucleus and cytoplasm of the new dehydrated tissue were distinct, and the chromaticity, color and transparency of the tissue were not different from those of the conventional dehydration procedure; Immunohistochemical staining was performed on different tissues of rats, and the comparison result were no different from conventional embedded tissue immunohistochemical staining. Conclusion N-butanol combined with turpentine for tissue dehydration can not only avoid the toxic effect of xylene on human, but also reduce the tissue damage caused by excessive dehydration of anhydrous alcohol.
ABSTRACT
OBJECTIVE@#To explore the frequency of vitamin D receptor (VDR) Fok I polymorphism in healthy Chinese and colorectal tumor patients,and to study the correlation between VDR Fok I polymorphism and the pathogenesis of colorectal tumor.@*METHODS@#After the preparation of gDNA by common method,VDR genotypes were determined by Fok I restriction endonuclease digestion of PCR-amplified DNA in 69 colorectal cancer patients and 218 healthy persons.@*RESULTS@#The F allele frequencies of VDR in healthy persons and in colorectal tumors patients were 61.5% and 49.3%, respectively, with statistical difference (P< 0.05). The genotype frequencies of FF, Ff and ff in healthy persons and in colorectal tumors patient were (39.5%,44%,16.5%) and (29.1%,40.5%,30.4%), respectively,with statistical differences (P< 0.05). The odds ratio of ff and Ff genotypes were 2.51 (95% confidence interval,1.21 approximately 5.18) and 2.00 (95% confidence intervals,1.01approximately 3.96), respectively (P< 0.01).@*CONCLUSION@#Fok I polymorphism is a common single nucleotide polymorphism (SNP) of VDR in Chinese population,and the VDR Fok I polymorphism may lower the risk of colorectal tumor.