[A historical review of early Sino-American communication in Chinese materia medica: Three historical events from the 17th century to 1848].

The early period of Sino-American communication in Chinese materia medica referred to the historical period from the 17th century, European trade overseas and the frequent communication of missionaries, to 1848 when gold prospectors from China travelled to America. This paper reviewed and examined the three historical events in this period : the spread, trade, and introduction of tea; the first edition of the United States Pharmacopoeia and its collection of Chinese medicines and preparations; and the discovery and trade of American ginseng hoping to explore the basic historical facts of the spread and exchange of Chinese medicine between China and America in the early period. The paper explored these historical factors, provided effective references for developing cooperation in public health between China and America and the start of the constructing of a Global Community of Health for All.

Effect of Na2O and ZnO on the microstructure and properties of laser cladding derived CaO-SiO2 ceramic coatings on titanium alloys.

To improve the bioactivity of titanium alloy (Ti-6Al-4V), CaO-SiO2 coatings on titanium alloys were fabricated using laser cladding method. The effect of Na2O and ZnO on the microstructure and properties of the prepared coatings was discussed. The microstructure of the CaO-SiO2 coatings consists of cellular grains and cellular dendrites. The mutual diffusion of elements occurs between the coating and substrate. The base CaO-SiO2 coating is composed of different phases including CaTiO3, α-Ca2(SiO4), SiO2, TiO2 and CaO. The formation of CaTiO3 in the ceramic layer was analyzed through thermodynamics. Na2O has little influence on the microstructure, average hardness and wear resistance. When ZnO is added to the precursor, the microstructure turns to cell dendrite, and ZnO and Zn2SiO4 appear in the corresponding coating. The addition of ZnO reduces the average hardness and wear resistance of the ceramic layer. The in vitro soaking in SBF shows that the laser cladding coating has the ability to form an apatite layer.

[Relationship of DNMT3b expression and SEPT9 methylation in theprogression of colorectal carcinogenesis].

Objective: To investigate the relationship between the expression of DNA methyltransferase 3b (DNMT3b) and the methylation of SEPT9 gene, and their application prospects in the diagnosis and treatment of colorectal cancer. Methods: Seventy-five cases of colorectal cancer and adjacent tissues, 68 cases of colorectal high-grade internal neoplasia tissues (referred to as precancerous tissues) and high-grade internal adjacent neoplasia tissues (referred to as adjacent precancerous tissues) were collected. Pyrosequencing was used to detect the methylationlevel of SETP9. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to examine the mRNA expressionof SEPT9 and immunohistochemistry(IHC) was applied to detect the protein expressions of SETP9 and DNMT3b. Liposome-mediated method was used to transfect DNMT3b siRNA and negative control siRNA into HT-29 cells. Five groups including DNMT3b siRNA 15 nmol/L group, DNMT3b siRNA 30 nmol/L group, negative control siRNA 15 nmol/L group, negative control siRNA 30 nmol/L group and blank control group were set up. Pyrosequencing was applied to determine the methylation level of SEPT9 and mRNA expression of DNMT3b in each group. Results: The methylation rates of SEPT9 gene in colorectal cancer tissues, adjacent tissues, precancerous tissues and adjacent precancerous tissues were (76.8±6.5)%, (14.4±2.6)%, (34.6±5.0)% and (7.4±1.2)%, respectively, which was highest in colorectal cancer tissue (P<0.001). The relative expressions of SEPT9 mRNA were 0.18±0.03, 0.89±0.41, 0.69±0.41 and 1.01±0.21, respectively, which was lowest in colorectal cancer tissue (P<0.001), while there were no statistically significant differences in adjacent tissues, precancerous tissues and adjacent precancerous tissues (P>0.05). The positive rates of SEPT9 protein expression were 12.0% (9/75), 53.3% (40/75), 55.1% (38/69) and 62.3% (43/69), which was lowest in the colorectal cancer tissue (P<0.001), while there were no statistically significant differences in the adjacent group, precancerous group and adjacent precancerous group (P>0.016 7). The positive rates of DNMT3b protein expression were 56.3% (45/75), 26.7% (20/75), 46.4% (32/69) and 33.3% (23/69), respectively, which was highest in colorectal cancer tissue (P<0.001), while without statistically significant difference from the precancerous tissue (P>0.016 7). Experiments in vitro showed that DNMT3b mRNA expression was lowest in DNMT3b siRNA 30 nmol/L group among five groups and was statistically different from other groups (all P<0.05). Meanwhile, the methylationrate of SEPT9 gene was lowest in this group, but without statistically significant difference from the DNMT3b siRNA 15 nmol/L group (P>0.05). Conclusions: The expression of DNMT3b is significantly correlated with the methylation level of SEPT9 gene in different stages of colorectal cancer. The high expression of DNMT3b may be an important molecular event before SEPT9 gene methylation and it may have an important potential application value in the diagnosis and treatment of early colorectal cancer.

[Studies on the alkaloids of radix Sophorae Tonkinensis].

Six alkaloids were isolated from Radix Sophorae Tonkinensis. On the basis of spectrometric analysis and physico-chemical constants they were identified as (I) (+)-matrine, (II) (-)-cytisine, (III) (+)-matrine N-oxide, (IV)(+)-sophocarpine N-oxide, (V)(+)-sophoramine and (VI) (+)-sophoranol respectively. (II), (IV), (V) and (VI) were isolated for the first time from Radix Sophorae Tonkinensis.

[Studies on the relation of alkaloids in semen Strychni and its processing].

This paper reports the determination of strychnine and brucine in different parts of Semen Strychni (the seeds of Strychnos nux-vomica and S. pierriana), and makes a comparison of the contents between the crude forms and processed products of the two seeds. Based on the results, the authors have made some discussion about the relationship between the alkaloid distribution in Semen Strychni and its processing.

Characterization of an Escherichia coli K12 mutant that is sensitive to chlorate when grown aerobically.

Escherichia coli can normally grow aerobically in the presence of chlorate; however, mutants can be isolated that can no longer grow under these conditions. We present here the biochemical characterization of one such mutant and show that the primary genetic lesion occurs in the ubiquinone-8-biosynthetic pathway. As a consequence of this, under aerobic growth conditions the mutant is apparently unable to synthesize formate dehydrogenase, but can synthesize a Benzyl Viologen-dependent nitrate reductase activity. The nature of this activity is discussed.