Staphylococcus epidermidis (S. epidermidis) is one of the common opportunistic pathogens causing nosocomial infections. Although it is known that the bacteria can form biofilms by adhering to indwelling medical devices there is no optimal animal model for in ν1νo study. To establish an animal model for biofilm infection , the serum samples from several animal species were collected and their inhibitory effects on in vitro S. epidermidis (ATCC RP62A) biofilm formation were observed. New Zealand white rabbit was selected as the leading candidate for its relatively weaker inhibition on biofilm formation. Dishes cut from 96-well plates were sterilized and implanted subcutaneously , followed by injection of 1 ml (109 CFU/ mJ) bacteria in situ. Biofilms formed on the dishes in the New Zealand white rabbit model after 72 h shared morphological similarity with that formed in νitro observed under confocal laser scanning microscope and scanning electron microscope. Furthermore, the effect of vancomycin against S. epidermidis biofilm fomation in viνo was investigated. The results showed that the viable bacterial cells in biofilm treated with vancomycin (8μg/ml, local injection) was significantly lower ( P< 0.01) than that in non-treatment group. The New Zealand white rabbit model for S. epidermidis biofilm formation was established. This model can be used for the observation of biofilm morphology and evaluation of effectiveness of antimicrobial treatment ln νiνo.
The pathogenesis of tuberculous pleurisy remains unclear. Evidences have shown that immuno-imbalance is an important risk factor for this condition. The present paper aimed to profile CD4 + and CD8 + T cells in patients with tuberculous pleurisy. A total of 30 cases were selected and their peripheral blood and pleural fluid were collected. The mononuclear cells were isolated. The CD4 + cells, CD8 + T cells, activation surface markers of human leukocyte antigen (HLA)-DR, and granzyme B level in CD8+ T cells were detected by flow cytometry. The results showed that the proportions of CD3 + , CD4 + and CD8 + T cells in peripheral blood samples collected from the patients with tuberculous pleurisy were lower than those in the control group. The proportions of CD3 + and CD4 + T cells in patients' pleural effusion were higher than those in peripheral blood, but the proportion of CD8 + T cells had no significant difference. The levels of HLA-DR on CD4 + and CD8 + T cells in peripheral blood in patients with tuberculous pleurisy were higher than those in the control group. And the level of CD8+ granzyme B+ T cells in patients with tuberculous pleurisy was lower than that in the control group. In patients , the levels of CD4 + HLA + , CD8 + HLA + and CD8+ granzyme B+ T cells in pleural effusion were lower than those in peripheral blood. In patients' peripheral blood there was a positive correlation between CD8 + T cells and granzyme B level. The results suggested that the immune response between peripheral blood and pleural fluid in patients with tuberculous pleurisy were different. Immuno-imbalance may play a critical role in the development/prognosis of the disease.
In order to investigate the current Helicobacter pylori (Hp) infection and the related factors , a self-designed questionnaire was distributed and collected from 723 patients who received Hp detection. The factors related to Hp infection were analyzed. The total Hp infection rate was 43.2%. A significant difference between male (50. 1 %) and female (34.9 %) ( P< 0.05 ) was observed. The results indicate that the factors related to Hp infection include education, stress, diet, physical exercise, water-drinking habits, health habits and digestive system disease , and consistent with published reports. Therefore , clinical detection of Hp and health education should be strengthened to prevent Hp infection.
The present paper aims to compare the sensitivity , specificity and accordance rate of consensusdegenerate hybrid oligonucleotide primer polymerase chain reaction (CODEHOP PCR) technique and commercial kit in diagnosis of paramyxovirus infection in clinical specimens and to further evaluate the value of CODEHOP PCR assay in detection of known and novel respiratory viruses. A total of 572 specimens from lower respiratory tract were collected from Children' Hospital of Shanghai inpatients with acute respiratory infections during 2011. These specimens were analyzed by CODEHOP PCR and commercial RV12 kit for the detection of paramyxoviruses, including known parainfluenza virus type 1 (PIV-1) , PIV-2 , PIV-3 , respiratory syncytial virus A (RSVA) , RSVB, human metapneumovirus (HMPV) and novel viruses. The results showed that 102 out of 572 specimens (19.76%) were detected positive by the RV12 kit, and 113 were detected positive by CODEHOP PCR. The accordance rate of the two methods was 85.39%. CODEHOP PCR is more sensitive than RV12 kit in detecting RSVA infection in cell culture. The study suggests that CODEHOP PCR is a powerful technique for the identification of paramyxoviruses in clinical specimens. It can be optimized by combining with some new techniques, and is worthy of application in the future.
Rapid-growing mycobacterium is a common pathogen for non-tuberculous mycobacterial diseases. In October 2012 , a strain of rapid-growing mycobacterium was isolated from abscess fluid and tissue lesions of an outpatient in our department. The morphological features of the strain were shown as follows: unequal size, slightly dry, off-white, non-hemolytic, greasy-like in saline smear, and Gram stain-positive with pale and uneven color. The acid-fast staining showed strong positive and branched. The strain was identified as Mycobacterium chelonei through sequencing and BLAST analysis. The combination therapy of amikacin, clarithromycin, cefoxitin and rifampin was effective.
Enterovirus 71 (EV71) infection leads to hand, foot and mouth disease (HFMD) and neurological complications. It has caused many pandemics worldwide. In order to develop effective medicines and vaccines to treat HFMD caused by EV71, the researchers have been studying EV71 pathogenesis using susceptible cells and experimental animals. The in νitro and in vivo models are summarized in this paper.
Bacterial 16S rDNA amplification and sequencing is a new tool which has been widely used to identify bacterial species and perform taxonomic studies. The application of this technology for identification of uncultivable bacteria, differentiating species with high DNA sequence similarity and discovering novel bacterial genus and species are introduced in this paper. Future perspective of the method in clinical microbiology laboratories is also discussed.
Pseudomonas aeruginosa is a conditional pathogen and the leading species isolated from hospitalacquired infections. With the increasing and unrational usage of antibiotics , the resistance of Pseudomonas aeruginosa to β-lactam antibiotics has gradually increased, and then the anti-infection therapy in hospitals becomes even more difficult. The resistance mechanism of Pseudomonas aeruginosa to β-lactam antibiotics is complex, including natural and acquired drug-resistance. In this paper, the recent researches on mechanisms of resistance to β-lactam antibiotics and transmission of Pseudomonas aeruginosa are reviewed.
Melioidosis, caused by the inoculation, inhalation and ingestion of Burkholderia pseudomallei, is a classical tropical amphixenosis characterized by multi-abscess , tough pneumonia and fatal septicemia. The mortality rate of this disease is up to 40%. Its endemic regions are mainly among North Australia, Southeast Asia, with sporadic cases reported from North America and other areas. Melioidosis may have a wide range of clinical manifestations, varying from an acute fulminant septic illness to a chronic infection. High misdiagnosis rate, high resistance rate and long period of antibiotic therarapy combined with high relapse rate are the major barriers to treatment . With the globalization and increasing risk of imported cases, it is necessary to effectively prevent and cure melioidosis. The current research progress and clinical advice are summarized in this paper.
E5 protein of human papillomavirus type 16 plays an important role in cervical carcinogenesis. It has a direct transformation function through up-regulation of epidermal growth factor receptor (EGFR) pathway , and also contributes to the transformation function of E6 protein and E7 protein. In recent years, it has been found that HPV16 E5 protein affects some immunological factors and some key factors in inflammatory pathway. It is a leading therapeutic target for cervical cancer. Current research progress on HPV16 E5 protein is reviewed in this paper.
Acute viral infection could form effective antiviral immune response. Naive T cells undergo clonal expansion and give rise to abundant antigen-specific T cells. Some of these T cells differentiate into effector T cells, secrete cytokines and clear the virus. After that, a majority of the effector T cell population dies. Once re-exposure to the antigen , the surviving T cells differentiate into memory T cells and form effective antiviral immunity response. In contrast, chronic viral infections result in T cell function impairment gradually , characterized by losing effector functions and replication potential , and losing the control of the viral infection. In this paper, the characteristics of T cell exhaustion , the advance in maintaining and promoting the exhausted state , especially the advance in chronic human immunodeficiency virus infection are reviewed.