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Chun-Hua Li

Publications and source records attributed to Chun-Hua Li.

2 recordsLinked to original sources
PubMed2005

[Determination of expression of protamine-2 mRNA in different positions of the testis of patients with nonobstructive azoospermia].

OBJECTIVE: To investigate the relationship between the expression of protamine-2 (P-2) mRNA and the results of sperm extraction in the corresponding testis tissues of patients with nonobstructive azoospermia. METHODS: Based on pathological diagnosis, 38 cases of azoospermia at the mean age of 32.4 (ranging 24 - 42) years were divided into a nonobstructive (NOA) group and an obstructive (OA) group. Two specimens were taken from different positions of one testis, each divided into three portions for general pathological test, sperm separation and mRNA extraction, respectively. The expression of P-2 mRNA was determined by RT-PCR and image analysis assay. RESULTS: Among the 38 cases, 27 were diagnosed as nonobstructive and 11 as obstructive azoospermia. No regularity was found as to the positions where sperm could or could not be successfully isolated. The expression of P-2 mRNA was 1.40 +/- 0.21 in the tissues where sperm was isolated and 0.51 +/- 0.23 (P < 0.05) in those where no sperm was isolated. CONCLUSION: The expression of P-2 mRNA in the testicular tissues from the patient with nonobstructive azoospermia could reveal the results of sperm extraction in the corresponding tissues.

Adult↗
PubMed2003

A soft docking algorithm for predicting the structures of protein-protein complexes.

An efficient soft docking algorithm is described to predict the mode of binding between two proteins based on the three-dimensional structures of molecules. The molecular model used in this work was grounded on the "simplified protein" model used in Janin's docking algorithm. The side chain flexibility of the amino acid residues Arg, Lys, Asp, Glu and Met at the protein surface was considered through softening the molecular surface. A double filtering technique was used to eliminate most of the unlike binding modes. The energy minimization was performed on the retained structures, and then these structures were evaluated with the scoring function which included electrostatic, desolvation and van der Waals energy terms. The 26 complexes were used to test this docking algorithm and good results were obtained. The native-like conformations of all the complexes were all found, of which 20 were ranked in the top 10.

Algorithms↗