Objective To investigate the relationship between the polymorphism of 7α-hydroxylase (CYP7A1) and cholestero1 cholecystolithiasis. Methods CYP7A-1 genotyping was performed by PCR-RFLP approach in 160 cholesterol cholecystolithiasis patients and 94 control subjects.Results The frequencies of C, A allele of CYP7A1 gene were 83.75%, 16.25% in cholesterol cholecystolithiasis patients and 81.91% and 18.09% in control group. There was no significant difference in frequencies of allele and genotype in A-204C polymorphism between two groups (Pgt;0.05). In control group and cholesterol cholecystolithiasis group， LDL-C levels in AA genotypes were lower than those in CC and CA genotype (Plt;0.05). Conclusion The results indicate that no direct association is found between CYP7A-1 gene and cholesterol cholecystolithiasis，but there is significant correlation between the polymorphism of the CYP7A-1 gene and the levels of LDL-C.
Objectives To investigate the frequency of LTC4S A-444C polymorphism in Chinese Han population in Beijing and to evaluate its association with susceptibility to asthma，asthma severity and clinical response to leukotriene receptor antagonist.Methods The LTC4S A-444C polymorphism was analyzed in 101 patients with asthma and 105 healthy controls.Then 18 asthmatics were recruited，and a 2-week prospective，open trial of montelukast was performed in addition to the previous medications.Results In the asthma group，the frequencies of A and C allele at -444 locus of LTC4S gene were 81.0% and 19.0%，respectively，and genotype frequencies of AA，AC and CC were 65.4%，30.5% and 3.8%，respectively.There was no significant difference in LTC4S A-444C polymorphism between the asthmatics and healthy controls（Pgt;0.05）.The asthmatics with the C-444 allele had significantly lower forced expiratory volume in one second（FEV1） than wild-type A homozygotes [（58.6±21.6）% predicted vs （70.3±22.4）% predicted，Plt;0.05）].A correlation was observed between the variant C-444 allele and asthma severity（Plt;0.05）.After administered montelukast 1 week，the A-444 allele homozygotes（n=9） responded better than the C（-444） allele carriers（n=7）[（10.8±10.2）% vs （–9.8±16.2）% improvement of FEV1，Plt;0.05].After 2 weeks，the A-444 allele hemozygotes also responded better，although there was no statistical difference（Pgt;0.05）.Conclusion In Chinese Han population LTC4S A-444C polymorphism is associated with asthma severity and probably contributes to the clinical response to leukotriene receptor antagonists.
Objective To investigate the mutations of quinolone resistance determinational region ( QRDR) in fluoroquinolon-resistant Pseudomonas aeruginosa strains isolated from patients with nosocomial pneumonia. Methods Eight-four Pseudomonas aeruginosa strains isolated from patients with nosocomial pneumonia in Xinhua Hospital during January 2006 to December 2007, from whom fluoroquinolon-resistant resisitant ( case) and fluoroquinolon-susceptible ( control ) Pseudomona aeruginosa were identified. The mutation of QRDR was tested by restriction fragment length polymorphism ( RFLP) and gene sequencing.The relationship between QRDR mutations and clinical prescription was analyzed. Results Mutation in QRDR was found in 42 isolates among the 50 fluoroquinlon-resisitant isolates( 84. 0% ) , while no mutation was found in fluoroquinlon-susceptible isolates. The mutation in GyrB Ser464 was found in 34 isolates ( 68. 0% ) . There was statistical difference in the usage of β-lactams between the GyrB-Ser464-mutated group and the non-GyrB-Ser464-mutated group( OR = 11. 3, P = 0. 003 and OR = 3. 5, P = 0. 023) , also in the time of fluoroquinolon usage before isolated ( P = 0. 038) . Conclusions The mutation of QRDR is contributing to fluoroquindor-resisitance of Pseudomona aeruginosa, most of which lies in GyrB Ser464.Abuse of β-lactams and fluoroquinolon may be the risk factors of mutation in GyrB Ser464.