Low genetic variation in Echinococcus multilocularis from the Western Sichuan Plateau of China revealed by microsatellite and mitochondrial DNA markers.

The prevalence of E. multilocularis is a major public health problem in China. To better understand the molecular epidemiology and evolutionary patterns of E.

Polymorphism of MTHFR 1298A>C in relation to adverse pregnancy outcomes in Chinese populations.

Background: Adverse pregnancy outcomes (APOs) are involved in a series of abnormal pregnancies like embryo growth arrest, spontaneous abortion, premature birth, stillbirth, fetal malformation, birth defects and other pathological pregnancy, and childbirth complications. Polymorphism of methylenetetrahydrofolate reductase gene (MTHFR, 607093) is one of the main genetic causes of APO. However, there is still debate on whether MTHFR 1298A>C, rs1801131, polymorphism is related to APO.

Spectrofluorimetric determination of trace nitrite with a novel fluorescent probe.

A simple, sensitive and selective fluorimetric determination for trace nitrites was developed using an unsymmetrical rhodamine with a high fluorescence quantum yield and large Stokes shift. The method is based on the reaction of the unsymmetrical rhodamine with nitrite in an acidic medium to form a nitroso product, which has much lower fluorescence because the electron-withdrawing effect of the nitroso group influences the system of p-pi conjugation between N atom and benzene ring. Under optimum conditions, the fluorescence quenching intensity is linear over a nitrite concentration range of 1.

(S)-1-Hydroxy-propan-2-aminium (2R,3R)-3-carb-oxy-2,3-dihydroxy-propanoate monohydrate.

The chiral title compound, C(4)H(10)NO(+)·C(4)H(5)O(6) (-)·H(2)O, is a hydrated mol-ecular salt in which the tartaric acid has transferred one proton to the (S)-2-amino-propan-1-ol mol-ecule. The crystal structure is stabilized by a three-dimensional network of N-H⋯O and O-H⋯O hydrogen bonds. The absolute configuration was assigned on the basis of the starting materials.

New fluorescent labels: 4- and 7-chlorofluorescein.

A new mixture of 4- and 7-chlorofluorescein were synthesized by condensation of resorcinol with 3-chlorophthalic anhydride in the presence of methanesulfonic acid or zinc chloride. These regioisomers were successfully separated by chromatography. The photophysical properties were examined and their absorption and emission maxima at long wavelength, high fluorescence quantum yield, and narrow emission bandwidth were found, highly favorable for detecting multiple target substances in the same sample.