Objective:To establish an HPLC method for the determination of gabapentin and the related substances in gabapentin capsules. Methods:A Kromasil C8 column (250 mm × 4. 6 mm,5μm)was used. The mobile phase was methanol-0. 01 mol·L-1 po-tassium dihydrogen phosphate solution (adjusting pH to 6. 9 with 2 mol·L-1 potassium hydroxide) (40∶60). The detection wave-length was 210 nm. The column temperature was 40℃ and the injection volume was 20μl. The main component and the known impuri-ty were determined by an external standard method. The unknown impurities were determined by a self-control method. Results: The calibration curve of gabapentin was linear within the range of 2.5-20.0 mg·ml-1(r=0.999 9). The average sample recovery was 100. 74% with RSD of 0. 24%(n=5). Conclusion:The method is simple, accurate,specific and applicable in the determination of gabapentin and the related substances in gabapentin capsules.

Reflex tests are ordered when a particular test result indicates that additional testing should be performed according to the guidelines or the feedback process formulated by clinical consultation. The application scope of the reflex tests involves various subspecialties of laboratory medicine. The clinical application needs the support of qualified laboratory doctors, comprehensive information and financial system, clinical guidelines, and so on. Active application of reflex tests can promote the standardization of evidence-based medicine in clinical practice, save medical resources, and shorten the diagnosis and treatment time of patients.

Objective To analysis the related factors and the morbidity of patients with Chlamydia trachomatis(CT),Neisse-ria gonorrhea(NG),Ureaplasma urealyticum (UU)in Beijing Union Medical College Hospital.Methods Simultaneous Am-plification and Testing (SAT)was used to detect CT-RNA,NG-RNA,UU-RNA of patients from January of 2013 to Decem-ber of 2014.Results There were 6 262 cases in all and 2 412 cases in 2013,and 3 850 cases in 2014.The positive rate of CT-RNA,NG-RNA and UU-RNA were 7.29%,3.44% and 38.21% in 2013.The positive rate of CT-RNA,NG-RNA and UU-RNA were 8.17%,4.15% and 45.71% in 2014 respectively,which were higher than those of in 2013.There was a signifi-cant difference in UU-RNA positive rate between the two years (χ2 =12.66,P <0.01).The positive rate of CT-RNA,NG-RNA and UU-RNA were 8.15%,3.89% and 42.77% respectively in two years.The positive rate of UU-RNA in women’s (61.05%)was significantly higher than the men’s (24.50%)(χ2 =316.13,P <0.01).Most of the people with CT-RNA, NG-RNA and UU-RNA-positive were between 21 to 30 years old.The highest detection positive rate was in cervical swabs samples of UU-RNA.Conclusion There was a significantly increasing trend of the infection with UU.Male were more sus-ceptible to CT and NG.However,female were more susceptible to UU.There was the highest infection rate in youth (21~30 years)with CT,NG and UU.

Objective To compare the detecting results of rotavirus (RV)and adenovirus (AdV)antigens using auto stool pretreatment system (machine method)and manual method.Methods A total of 100 stools collectecd from diarrear patients admitted in gastroenterology outpatient department from September 2014 to Octorber 2014 in Peking University Medical College Hospital were detected to identify RV and AdV antigens using machine method and manual method respectively,and the nucletic acids of positive samples were detected by liquid chip method to verify the results.Results The RV,AdV and co-infection antigen positive detection rate using machine method were 17.0% (17/100),25.0% (25/100)and 12.0% (12/100)respectively,whereas those using the manual method were 4.0% (4/100),13.0% (13/100)and 2.0% (2/100),re-spectively.Taking the nucletic acids detection as the golden method,the false positive detection rate of RV,AdV and co-in-fection antigen using machine method were 23.5% (4/17),20.0% (5/25)and 33.3% (4/12)respectively,whereas those u-sing the manual method were 75.0% (3/4),69.2% (9/13)and 50.0% (1/2),respectively.χ2 test for paired data for RV and AdV positive detection rate,false positive detection rate of RV and false positive detection rate of AdV using two meth-ods were statistically significant (χ2 =15.0,52.8 and 47.5,P values <0.05).Two methods for detecting RV and AdV had poor consistency (Kappa value was 0.25,Kappa values <0.4).Conclusion Machine method has much more advantage on RV and AdV positive detection rate and false positive detection rate than manual method,which is good for clinical applica-tion.

Objective To investigate the dynamic abnormality of anorectum in elderly patients with chronic constipation.Methods Anorectal perfusion manometry was performed to detect the change of anal canal pressure and the rectal sensation capacity in 58 elderly patients and 36 non-elderly adults with chronic constipation.The results were compared retrospectively.Results Anal resting pressure in a chronic constipation was significantly lower in elderly patients than in non-elderly adults,with statistically significant difference [(59.74 ± 2.31) mmHg vs.(68.22 ± 2.37) mmHg,t =2.430,P =0.017].The incidence of paradoxical motility of anal sphincter was significantly higher in elderly patients with three abnormalities(incomplete defecation,Bristol stool scale type 3-5 and straining at defecation) than in elderly patients without above three abnormalities (x2 =8.880、11.540、6.070,P =0.003、0.001、0.014).Maximal tolerable volume was significant lower in elderly patients with straining at defecation and abdominal pain than in control group (t =2.140,2.260,both P ＜ 0.05).No correlation was observed between sex and anorectal motility in elderly patients with chronic constipation.Conclusions Anorectal motility in elderly patients with chronic constipation is different from that in non-elderly patients with chronic constipation.The dynamic abnormalities of anorectum in chronic constipation are different in elderly patients with different symptoms.

Chronic gastritis has varied clinical symptoms and prolonged course,and seriously affects the life quality of patients.Studies have shown that mood disorders might affect the pathogenesis of chronic gastritis.Aims:To investigate the incidence of anxiety and depression and its relationship with digestive symptoms,Helicobacter pylori (Hp) infection,degree and activity of inflammation in patients with chronic gastritis.Methods:A total of 235 patients with chronic non-atrophic gastritis were enrolled.Anxiety,depression,gastrointestinal symptoms,gastric mucosal inflammation and activity were evaluated,and infection of Hp was detected.Results:In the 235 patients,144 (61.3%)were accompanied by anxiety and/or depression:108 patients (46.0%)were accompanied by anxiety,129 patients (54.9%) were accompanied by depression,93 patients (39.6%)were accompanied by anxiety and depression.Incidence of abdominal pain,abdominal distention and early satiety,scores of digestive symptoms,positive rate of Hp infection and incidence of severe inflammation in patients accompanied by anxiety and/or depression were significantly higher than those in patients without anxiety and depression (P<0.05 ),but no significant difference in inflammation activity was seen between the two groups (P>0.05).Conclusions:Incidence of anxiety and depression in patients with chronic gastritis is high.Anxiety and depression are associated with abdominal pain,abdominal distention and early satiety,and can affect the inflammatory degree of gastric mucosa.Patients with anxiety and depression are susceptible to Hp infection.

Objective To investigate the antimicrobial resistance proifle in the clinical bacterial strains isolated from Peking Union Medical College Hospital during 2014.Methods A total of 8 295 nonduplicate clinical isolates were collected. Disc diffusion test (Kirby-Bauer method) and automated systems were employed to study the antimicrobial susceptibility. The data were analyzed by using WHONET 5.6 software according to CLSI 2014 breakpoints.Results Of the 8 295 isolates, 67.4% were gram-negative, and 32.6% were gram-positive. The top 10 most frequently isolated bacteria were:E. coli(18.1%),P. aeruginosa (10.8%),K. pneumoniae (10.2%),S. aureus (9.8%),
A. baumannii(9.2%),E. faecalis (6.3%),E. faecium (4.1%), coagulase-negativeStaphylococcus (4.1%),E. cloacae (3.1%) andS. maltophilia (2.9%). Methicillin resistant strains inS. aureus (MRSA) and coagulase negativeStaphylococcus (MRCNS) accounted for average of 28.4% and 66.5%, respectively. The resistance rates of MR strains to β-lactams and other antimicrobial agents were much higher than those MS strains. Overall, 81.3% of MRSA strains were still susceptible to trimethoprim-sulfamethoxazole, while 81.1% of MRCNS strains were susceptible to rifampin. No staphylococcal strains were resistant to vancomycin, teicoplanin or linezolid. The resistance rate ofE. faecalis strains to most of the drugs tested (except chloramphenicol) was much lower than those ofE. faecium. Several strains of bothE. faecium andE. faecalis were found resistant to vancomycin and teicoplanin, which were Van-A and Van-B types based on their phenotype. No linezolid resistant enterococcal strains were found. Data showed that 90.8% ofβ-hemolyticStreptococcus strains were susceptible to penicillin. ESBLs-producing strains accounted for 54.2%, 31.0% and 28.9% inE. coli,Klebsiella spp (K. pneumoniae andK. oxytoca) andP. mirabilis, respectively.Enterobacteriaceae isolates were still highly susceptible to carbapenems. Overall, no more than 3.3% of these strains were resistant to carbapenems. A few extensively drug-resistant strains ofK. pneumoniae (1.3%, 11/842) were identiifed. The resistance rates ofP. aeruginosa to imipenem and meropenem were 17.5% and 11.8%, respectively.P. aeruginosa isolates showed the lowest resistance rate (5.9%) to amikacin. And 69.0% and 67.4% ofA. baumanniiisolates were resistant to imipenem and meropenem.A. baumannii isolates showed the lowest resistance rates to cefoperazone-sulbactam and minocycline (47.8% and 28.7%), respectively. The prevalence of extensively drug-resistant strains was 32.3% inA. baumannii and 1.8% inP. aeruginosa. The prevalence of β-lactamase inH. inlfuenzae was 33.7%. More than 93.0% ofS. pneumoniae strains were resistant to erythromycin and clindamycin.Conelusions Bacterial resistance is still increasing in this hospital, especially carbapenem resistantEnterobacteriaceae. It is necessary to take effective hospital infection control measures and use antibiotics rationally.

Objective To investigate the profile of antimicrobial resistance in clinical isolates from the patients in Peking Union Medical College Hospital during 2012.Methods A total of 6 662 nonduplicate clinical isolates were collected.Disc diffusion test or Kirby-Bauer method and automated systems were employed to study the antimicrobial resistance.The data were analyzed by WHONET 5.6 software according to CLSI 2012 breakpoints.Results Of the 6 662 bacterial strains included in this analysis, gram negative organisms and gram positive cocci accounted for 66.7% (4 446/6 662)and 33.3% (2 216/6 662),respectively. The top 10 most frequently isolated microorganisms were E.coli (17%),P .aeruginosa (11.4%),A.baumannii (11.4%), S.aureus (11.2%),K.pneumoniae (9.2%),E.faecalis (8.4%),E.faecium (4.1%),coagulase negative Staphylococcus (3.3%),E.cloacae (3.1%)and S.maltophilia (3.1%).About 39.9% of the S.aureus strains and 73.4% of the coagulase negative Staphylococcus were methicillin-resistant.No staphylococcal strains were found resistant to vancomycin,teicoplanin or linezolid.A few of vancomycin-or teicoplanin-resistant strains were identified in both E.faecium and E.faecalis.No lin-ezolid resistant strains were found.ESBLs-producing strains accounted for 53.0%,25.7% and 27.0% in E.coli,Klebsiella spp.(K.pneumoniae and K.oxytoca)and P .mirabilis, respectively.The Enterobacteriaceae strains were still highly susceptible to carbapenems. Overall, less than 2.6% of these strains were resistant to carbapenems.A few pan-re-sistant strains of K.pneumoniae (0.7%,4/615)were iden-tified.About 20.3% and 13.6% of the P .aeruginosa isolates were resistant to imipenem and meropenem,respectively.P . aeruginosa isolates showed the lowest resistance rate (7.2%)to amikacin.And 72.8% and 75.2% of A.baumannii strains were resistant to imipenem and meropenem.A.baumannii isolates showed relatively low resistance rate to cefoperazone-sulbac-tam (51.2%)and minocycline (30.2%).The prevalence of pan-resistant strains was 43.5% in A.baumannii and 1.4% in P . aeruginosa.Conclusions Bacterial resistance is still increasing,especially pan-resistant A.baumannii strains.It is mandatory to take effective measures to control hospital infections and improve rational antibiotic use.

Background:Family history of gastric cancer is an important indicator of genetic susceptibility.Studies have shown that the family history of gastric cancer might have impact on Helicobacter pylori (Hp) infection and clinicopathological manifestations in patients with chronic gastritis.Aims:To investigate the correlation of family history of gastric cancer with Hp infection and pathological changes of gastric mucosa in patients with chronic gastritis.Methods:A total of 312 patients with chronic gastritis were enrolled to study the relationship between family history of gastric cancer and Hp infection,degree of gastric mucosal inflammation,activity of inflammation,and degree of atrophy and intestinal metaplasia.Results:In the 312 patients with chronic gastritis,165 (52.9％) had family history of gastric cancer,and 147 (47.1％) without family history of gastric cancer.Incidence of Hp infection,degree of gastric mucosal atrophy and intestinal metaplasia in patients with family history of gastric cancer were significantly higher than those without (P ＜ 0.05),but no significant differences in degree and activity of inflammation were found between the two groups (P ＞ 0.05).Conclusions:The incidence of Hp infection is higher in chronic gastritis patients with family history of gastric cancer.Family history of gastric cancer may aggravate gastric mucosal atrophy and intestinal metaplasia.

Objective To investigate the antimicrobial resistance of clinical bacterial isolates in Peking Union Medical College Hospital (PUMCH) in 2017. Methods A total of 9 515 non-duplicate clinical isolates were collected from January 1 to December 31, 2017. Disc diffusion test (Kirby-Bauer method) and E-test method were employed to determine antimicrobial susceptibility. Results Gram-negative bacilli and gram-positive cocci accounted for 68.2％ and 31.8％, respectively among the 9 515 clinical isolates. Methicillin-resistant strains in S. aureus (MRSA) and coagulase-negative Staphylococcus (MRCNS) accounted for 25.6％ and 73.3％, respectively. Extended-spectrum β-lactamases (ESBLs) -producing strains accounted for 47.6％ (877/1 842), 27.6％ (335/1 213) and 33.0％ (59/179) in E. coli, Klebsiella spp (K. pneumoniae and K. oxytoca) and P. mirabilis, respectively. Enterbacteriaceae strains were still highly susceptible to carbapenems, with an overall resistance rate of ≤ 3.8％. The resistance rates of K. pneumoniae to imipenem and meropenem were 8.5％ and 8.2％, respectively. About 72.7％ and 70.4％ of A. baumannii isolateswere resistant to imipenem and meropenem. The resistance rate of P. aeruginosa to imipenem and meropenem was 14.8％ and 10.0％, respectively. The prevalence of extensively drug-resistant strains in A. baumannii, P. aeruginosa and K. pneumoniae was 31.7％ (239/753), 1.0％ (10/1 035), and 3.0％ (33/1 117), respectively. Conclusions The common bacterialisolates show various level of resistance to antimicrobial agents. Laboratory staff should improve communication with clinicians to prevent the spread of resistant strains.