Meningococcal disease,caused by Neisseria meningitidis (Nm),is still one serious threatening infectious disease with high mortality.Vaccination is available for prevention and control of such disease.Based on the chemical structure of capsule polysaccharide,Nm strains were classified into 13 serogroups.Meningococcal polysaccharide vaccines and polysaccharide conjugated protein vaccine against serogroup A,C,W 135 and Y were efficacious and have been widely used.Because of poor immunogenicity and the structurally homologous with neural cell,capsule polysaccharide of serogroup B Nm can not be used as vaccine candidate.In last several decades,B group vaccines develoment focused on the proteins research.Based on the out membrane protein and reverse vaccinology technology,progress of B group vaccine were accelerated.Several meningococcal B vaccine showed favorable immunogenicity and efficacity.Some B vaccines have been licensed and widely used.

Haemophilus influenzae (Hi) is a pathogen exclusively found in humans. It causes a wide range of infections from the upper respiratory tract to serious invasive diseases. Such as pneumonia, septicemia and meningitis. Strains of Hi are usually classif ied into six serotypes a to f and nontypeable H. influenzae (NTHI) according to the antigenicities and compositions of their polysaccharide capsules. Hib was a common cause of serious infections in younger children. The polysaccharide-protein conjugate vaccines against Hib had almost eliminated H. influenzae as a cause of pediatric meningitis. However, NTHI remains an important pathogen, particularly in children and the elderly. Efforts to understand and control NTHI disease have been hampered by the diversity of these bacteria. This review introduced the study progress about pathogenic mechanism of NTHI. In order to provide the help for development of vaccine, clinic treatment and prevent the occurrence of diseases causing by NTHI.

In this study,the L.dumoffii TEX-KL (ATCC 33343),L.dumoffii NY23 (ATCC 33279) and L.pneumophila philadelphila-1 (ATCC 33155) strains were used to explore the adhesion,invasion and intracellular growth ability in the epithelial cells.Approximately 1× 108 bacteria were pelleted,resuspended,and diluted (1 ∶ 10) in RPMI 1640 tissue culture medium.The bacteria were then added to A549 cells (1 × 105 per well) in 24-well plates to give a multiplicity of infection (MOI) of about 100.The Gimenez staining and colony counting methods were used for the determination of the strain adhesion,invasion and intracellular growth ability.It was found that in vitro growth ability of L.pneumophila philadelphila-1,L.dumoffii TEX-KL and L.dumoffii NY23 strains had no significant difference.For in vivo assay,there was also no significant difference in adhesion ability of these strains.However,the CFU counts of L.dumoffii TEX-KL strain invaded into A549 cells was 1 000 times higher than that of the other two strains.Compared with L.pneumophila philadelphila-1 and L.dumoffii NY23 strains,L.dumoffii TEX-KL strain has higher invasion ability and,therefore,higher intracellular growth ability.

Objective To establish TaqMan real-time PCR method for detection and identification of Haemophilus influenzae and Streptococcus pneumonia. Methods Two sets of primers and FAM-labeled probes targeting different genes of Haemophilus influenzae and Streptococcus pneumoniae were designed and synthesized. The bexA gene was used for identification of Haemophilus influenzae and lytA for Streptococcus pneumoniae. The sensitivity and specificity of real-time PCR were assessed for different primers and probes. Cut-off values of cycle threshold (Ct) were determined. Two hundred and seventy-eight cerebrospinal fluid (CSF) specimens from suspected bacterial meningitis cases were detected by real-time PCR assay, latex agglutination test and bacteria culture simultaneously. Results Haemophilus influenzae isolates of serotype a to d could be detected and identified by bexA primers and probe. All Streptococcus pneumoniae isolates of different serotypes could be detected and identified by lytA primers and probe. The respective sensitivities for Haemophilus influenzae and Streptococcus pneumoniae were 10 and 90 genome DNA copies in each PCR reaction. Of the 278 CSF specimens, four were positive by Haemophilus influenzae and seven positive by Streptococcus pneumoniae when detected by real-time PCR. Of the four Haemophilus influenzae positive specimens, two were positive by culture and one positive hy latex. Of the seven Streptococcus pneumonia positive specimens, two were positive by culture and two positive by latex. Conclusions Real-time PCR could rapidly detect and identify Haemophilus influenzae of serotype a to d and Streptococcus pneumoniae of different serotypes with high sensitivity. TaqMan real-time PCR could be widely used for the diagnosis of invasive meningitis caused by Haemophilus influenzae and Streptococcus pneumoniae. It can improve the rate of positivity for diagnosis of suspicious bacterial meningitis cases.

The incidence of meningococcal disease is generally low globally at present. The epidemics, problems and challenges of meningococcal disease were described in order to provide support for prevention and control of meningococcal disease in China, especially in the areas of disease surveillance, epidemic changes, serogroup witching, vaccines and vaccination strategies and meningococcal group B vaccine development.

Objective:This retrospective study aims to determine the efficacy of chemotherapy and improve a salvage chemother-apy agent for metastatic colorectal cancer (MCRC) after failure of treatment with irinotecan and oxaliplatin. Methods:Between Janu-ary 2002 and March 2013, 37 patients with metastatic MCRC who had progressed after treatment with irinotecan and oxaliplatin were analyzed for their response rate (RR) and progression-free survival (PFS). Results:The overall RR of the 37 patients was 13.51%, with 5 cases of partial response (PR), 12 cases of disease stabilization (SD), and 20 cases of progression (PD). Compared with other chemo-therapy regimens, treatment with a pemetrexed-based chemotherapy agent had a higher RR (17.64%vs. 10.00%, P=0.64) without a lon-ger PFS (2.00 months vs. 1.63 months, HR=0.79, 95%, CI:0.35 to 1.78, P=0.58). Compared with other chemotherapy regimens, treat-ment with a raltirexed-based chemotherapy agent had a higher RR (16.67%vs. 12.00%, P=0.34) without a longer PFS (1.58 months vs. 1.90 months, HR=2.24, 95%, CI:0.98 to 5.12, P=0.06).Conclusion:In patients with MCRC after failure of treatment with irinotecan and oxaliplatin, a pemetrexed-based or raltirexed-based chemotherapy agent may beneficial during salvage treatment and is therefore worthy of further study.

Objective:This study aims to determine the efficacy of chemotherapy and to identify potential chemotherapy agents for advanced primary duodenal carcinoma (PDC). Methods:Fifty-six patients with advanced PDC, who did and did not receive chemo-therapy, were involved in this study. Response rates (RR), disease control rates (DCR), progression-free survival (PFS), and overall sur-vival (OS) were analyzed. Results:The overall RR and DCR of 43 patients were 19.04%and 71.42%, respectively. The patients who re-ceived chemotherapy agents fluorourzcil and oxaliplatin exhibited higher RR compared with patients who received other chemotherapy combinations (35.29%vs. 7.69%, P=0.010 9). Palliative chemotherapy improved the OS of patients with advanced PDC compared with patients who did not receive chemotherapy (13.35 months vs. 5.65 months, HR=0.203, 95%CI:0.083 to 0.497, P=0.000 5). Compared with the use of other chemotherapy regimens, treatment with a fluorourzcil-based chemotherapy agent resulted in a longer PFS (5.08 months vs. 1.08 months, HR=0.004, 95%CI:0.000 to 0.315, P=0.013 2). Multivariate analysis indicated mucinous histology and lymph mode metastasis as factors predictive of poor prognosis in patients with advanced PDC. Conclusion:Palliative chemotherapy may im-prove the OS of patients with advanced PDC.

objective To investigate the epidemiological and molecular typing features of the pathogenic Haemophilus influenzae(H.influenzae)by biotyping,serotyping and pulsed-field gel electrophoresis(PFGE).Methods A total of 273 invasive isolates of H influenzae were collected from the pediatric patients with pneumonia at Chengdu Children Hospital of Sichuan province from 1988 and 2004 to 2007.The idenbfication of H.influenzae strains were done according to the laboratory standard methodology described by Manual of Clinical Microbiology(American).All strains were biotyped according to Kilian's classification with the API[R]NH system.And serotyped by a slide agglutination assay with type a to f specific antlaerum as described by Pittman.PCR method for identification of H.influenzae were performed as described by Falla.One hundred of 273 strains were analyzed by PFGE as described by Saito with some modifications.The resuIts of PFGE were analyzed by Bionumerics soft(Version 4.0,Applied Maths BVBA,Belium).Restilts 78.2%of 273 cases occurred under 1 years old.Eight biotypes were found among the 273 H.influenzae isolates.17.6%(48/273)of all isolates belonged to biotype Ⅰ,43.6%(119/273)were biotype Ⅱ,22.7%(62/273)were biotype Ⅲ,7.3%(20/273)were biotype Ⅳ,5.9%(16/273)were biotype Ⅴ,0.4%(1/273)were biotype Ⅵ,1.8%(5/273)were biotype Ⅶ and 0.7%(2/273)were biotype Ⅷ.respeetively.99.6% of all 273 isolates were nontypeable.There was only one isolate was serotvpe f Ninty-six PFGE genotypes were obtained in this study.One hundred strains demonstrated a variety of genomic Datterns by PFGE.The most isolates of the flame PFGE genotype(type 35)was 3 isolates.Each of93 PFGE genotypes was represented by only a single isolate.The genotypes distribution didn't correlate with the time distribution of the strains were isolated.Conclusion Nontypeable H.influenzae primarily caused acute Dneumoma in children under 1 years old.They mostly belonged to biotype Ⅰ,Ⅱ and Ⅲ biotypes.The nontypeable H.influenzae strains appeared to more heterogeneous patterns by PFGE genotyping.Genotyping may helP understand the molecular characteristics of outbreak and endemicity according to the results of PFGE.PFGE genotyping proved to have a much stronger discriminatory power than either serotyping or biotyping.Our findings suggest that PFGE analysis is useful for the epidemiologieal study of H.influenzae infections.

The incidence of meningococcal disease is generally low globally at present. The epidemics, problems and challenges of meningococcal disease were described in order to provide support for prevention and control of meningococcal disease in China, especially in the areas of disease surveillance, epidemic changes, serogroup witching, vaccines and vaccination strategies and meningococcal group B vaccine development.

Objective To investigate the molecular characteristics of serogroup B neisseria meningitidis in China. Methods Total of 485 (100 strains isolated from cerebrospinal fluid or blood samples of encephalomyelitis cases, and 385 strains isolated from nasopharynx of healthy carriers) Meningococcal serogroup B (MenB) strains, isolated from 29 provinces of China between 1968 and 2016, were analyzed by multilocus sequence typing (MLST) and PorA typing methods. Further, the genetic diversity of three MenB vaccine proteins, FHbp, NadA and NHBA, were analyzed. Results The 485 study strains belonged to 270 sequence types (STs), 107 of which (representing 211 strains) could be grouped into ten clonal complexes (CC). CC4821 has been the predominant lineage in China since 2005 (28.7%, n=139). The most common PorA types of MenB strains from invasive meningococcal cases were P1.5-2,2?2 (10.0%, n=10), P1.5-1,2?2 (9.0%, n=9) and P1.5-1,10?4 (9.0%, n=9). Four hundred and twenty one strains had intact fhbp gene; variant 1, 2 and 3 accounted for 12.8% (54 strains), 85.0% (358 strains) and 2.2% (9 strains) respevtively. Ten out of 432 strains (2.3%) contained complete nadA gene. All the 172 strains for which the nhba gene was sequenced had intact gene sequence which corresponded to 68 peptide types. Conclusion CC4821 was the predominant CC of MenB strains in China; the vaccine proteins were diverse about the sequences. The vaccine proteins should be carefully selected when developing MenB vaccines in China.