OBJECTIVETo observe the ultrastructural change of the route of gut bacterial translocation in a rat with spinal cord injury (SCI).

METHODSForty Wistar rats were divided into the following groups: control group and 3 SCI groups (10 in each group). The rats in the SCI groups were established SCI model at 24 h, 48 h, and 72 h after SCI. Small intestine mucous membrane tissue was identified and assayed by transmission electron microscope, scanning electron microscope and immunofluorescence microscopy.

RESULTSSmall intestine mucous membrane tissue in control group was not damaged significantly, but those in SCI groups were damaged significantly. Proliferation bacteria in gut lumen attached on microvilli. The extracellular bacteria torn the intestinal barrier and perforated into the small intestinal mucosal epithelial cell. The bacteria and a lot of particles of the seriously damaged region penetrated into the lymphatic system and the blood system directly. Some bacteria were internalized into the goblet cell through the apical granule. Some bacteria and particles perforated into the submucosa of the M cell running the long axis of M cells through the tight junctions. In the microcirculation of mucosa, the bacteria that had already broken through the microvilli into blood circulation swim accompanying with erythrocytes.

CONCLUSIONThe routes of bacterial translocation interact and format a vicious circle. At early step, the transcellular pathway of bacterial translocation is major. Following with the destroyed small intestine mucous, the routes of bacterial translocation through the lymphatic system and the blood system become direct pathways. The goblet cell-dendritic cell and M cell pathway also play an important role in the bacterial translocation.

Animals ; Bacteria ; Bacterial Translocation ; Epithelial Cells ; microbiology ; Goblet Cells ; microbiology ; Intestinal Mucosa ; microbiology ; pathology ; ultrastructure ; Intestine, Small ; microbiology ; pathology ; ultrastructure ; Microvilli ; microbiology ; Rats ; Rats, Wistar ; Spinal Cord Injuries ; microbiology

The ability of several species of streptococcus and staphylococcus to adhere to human buccal epithelial cells was studied in vitro by using bacteria and epithelial cells isolated from human buccal cavity. Viridans streptococci were found adhering in highest numbers(65 +/- 8 bacteria per epithelial cell) to epithelial cells. Streptococcus pyogenes adhered in great numbers (44 +/- 4), whereas Streptococcus pneumoniae (26 +/- 2), Staphylococcus aureus (21 +/- 2), Staphylococcus epidermidis (14 +/- 2) adhered poorly. These data showed that bacteria differed in their ability to adhere to human buccal epithelial cells. This difference in adhesive ability between bacterial species may correlate with the ability of the bacteria to colonize oral surface of human.
Bacterial Physiology* ; Cheek ; Epithelial Cells ; Human ; In Vitro ; Mouth/microbiology* ; Staphylococcus/physiology ; Streptococcus/physiology

OBJECTIVE: To observe the changes of cell gap junction ultrastructure of gastric epithelial cells in patients with gastric cancer(GC) and precancerous lesion(PL),and to investigate the relation between these changes and H.pylori infection. METHODS: Seventy patients with GC, 88 with PL, and 33 with chronic superfial gastritis (CSG) were studied. H.pylori was detected by rapid urease test,basic fuchsin stain and 14C-urea breath test. The CagA gene of H.pylori was determined by polymerase chain reaction(PCR).The cell gap junction ultrastructure was observed under transmission electronic microscope. RESULTS: Length of junction/unit perimeter of gastric epithelial cells in patients with PL was smaller than that in CSG patients, and the smallest width of the intercellular space was bigger than that in CSG patients. The number of cell junction, the number of junction/unit perimeter, and the length of junction/unit perimeter in patients with GC were all smaller than those in patients with CSG or PL, and its smallest width of the intercellular space was bigger than that in patients with CSG. In patients with GC, the number of cell junction, the number of junction/unit perimeter and the length of junction/unit perimeter in CagA+ H.pylori group were smaller than those in CagA(-) H.pylori group, and its smallest width of the intercellular space was bigger than that in CagA(-) H.pylori group. In PL patients, the intercellular space decreased, and the length of cell junction of gastric epithelial cells became bigger after H.pylori eradication. The length of junction/unit perimeter in patients of H.pylori eradication was bigger than that in patients without eradication, and the smallest width of the intercellular space was smaller than that in patients without eradication. CONCLUSION The changes of cell gap junction of gastric epithelial cells in patients with GC and PL are associated with H.pylori infection especially CagA+ H.pylori infection. Eradication of H.pylori can promote the formation of cell junction.
Adenocarcinoma ; microbiology ; ultrastructure ; Epithelial Cells ; ultrastructure ; Female ; Gastric Mucosa ; ultrastructure ; Helicobacter Infections ; pathology ; Helicobacter pylori ; Humans ; Intercellular Junctions ; ultrastructure ; Male ; Precancerous Conditions ; microbiology ; ultrastructure ; Stomach Neoplasms ; microbiology ; ultrastructure

Interleukin-8 (IL-8) is an important activator and chemoattratant of neutrophils and has been implicated in airway inflammatory diseases. To explore the new gene therapeutic strategies for airway inflammation, plasmid expressing dominant negative myeloid differentiation protein (MyD88 DN) was constructed and transfected into human airway epithelial cell lines A549 and SPC-A-I. The cells were challenged with M. tuberculosis, P. aeruginosa or K. pneumoniae and the release of IL-8 was measured using ELISA. The results showed that the supernatants of M. tuberculosis and R. aeruginosa enhanced IL-8 release from the epithelial cells; and transfection of MyD88 DN diminished this effect. MyD88 DN also reduced IL-8 release from cells induced by live bacteria of P. aeruginosa or K. pneumoniae. These data suggest that MyD88 could be used as a target gene in the gene therapy of airway inflammation.
Cells, Cultured ; Epithelial Cells ; microbiology ; secretion ; Humans ; Interleukin-8 ; secretion ; Mycobacterium tuberculosis ; Myeloid Differentiation Factor 88 ; genetics ; Pseudomonas aeruginosa ; Transfection

OBJECTIVETo investigate the effects of baicalin against Candida albicans germ tube formation, and adherence to buccal epitherial and vaginal epitherial cells.

METHODVarious concentrations of baicalin (100, 50, 10 mg x L(-1)) were incubated with C. albicans suspension, the mixed suspension of C. albicans and human buccal epitherial cells, the mixed suspension of C. albicans and vaginal epitherial cells, respectively. The effects of baicalin on C. albicans germ tube formation, and adherence to buccal epitherial and vaginal epitherial cells were then assessed microscopically.

RESULTAll concentrations of baicalin could inhibit C. albicans germ tube formation, and adherent to buccal epitherial and vaginal epitherial cells,while there was no significant difference between standard and clinical strains.

CONCLUSIONBaicalin could inhibit C. albicans germ tube formation, and adherence to buccal epitherial and vaginal epitherial cells.

Adult ; Anti-Infective Agents ; pharmacology ; Candida albicans ; drug effects ; growth & development ; physiology ; Candidiasis ; drug therapy ; microbiology ; Cheek ; microbiology ; Epithelial Cells ; microbiology ; Female ; Flavonoids ; pharmacology ; Humans ; Mouth Mucosa ; microbiology ; Vagina ; microbiology ; Young Adult

OBJECTIVETo compare the ability of adhesion and invasion to epithelial cells by Porphyromonas gingivalis (Pg) strains with different fimA separated from Chinese.

METHODSCultured method and antibiotic protection method were used to determine the adhesive and invasive ability of Pg with different fimA genetypes. The adhesion was observed by scanning electron microscope.

RESULTSAll the strains adhered and invaded to KB cells, and the adhesion rate ranged from 0.523% to 37.125% and invasive rate from 0.017% to 3.750%.The adhesive and invasive ability among different fimA genotypes showed no significant difference (P > 0.05).

CONCLUSIONSThere is no significant correlation between fimA genotype and ability in adhesion and invasion to KB cells.

Bacterial Adhesion ; Chronic Periodontitis ; microbiology ; Epithelial Cells ; microbiology ; Fimbriae Proteins ; genetics ; physiology ; Genetic Variation ; Genotype ; Humans ; KB Cells ; microbiology ; ultrastructure ; Microscopy, Electron, Scanning ; Porphyromonas gingivalis ; genetics ; isolation & purification ; physiology

OBJECTIVETo explore the significance of clue cells in the diagnosis of male urogenital infection.

METHODSUrethra swabs or prostatic fluid of 264 male outpatients were collected and smeared directly on the slice to find clue cells under the ultramicroscopy. Meanwhile, the positive patients' spouses were detected for bacterial vaginosis (BV).

RESULTSThe positive rates of the urethra swabs and the prostatic fluid were 5.1% (11/215 ) and 2.0% (1/49), respectively. Nine cases in 11 of the patients' spouses (81.8%) were diagnosed as BV.

CONCLUSIONBV pathogen can attack and attach to the epithelia of male genitals to form clue cells. Clue cells positive, along with clinical symptoms, contribute to the diagnosis of male urogenital bacterial infection.

Adult ; Bacterial Infections ; diagnosis ; microbiology ; pathology ; Cervix Uteri ; microbiology ; Epithelial Cells ; microbiology ; Female ; Gardnerella vaginalis ; isolation & purification ; Humans ; Male ; Middle Aged ; Mycoplasma hominis ; isolation & purification ; Prostate ; microbiology ; Sensitivity and Specificity ; Spouses ; Ureaplasma urealyticum ; isolation & purification ; Urethra ; microbiology ; Urinary Tract Infections ; diagnosis ; microbiology ; pathology ; Vagina ; microbiology

OBJECTIVETo investigate the effect of annexin A2 (AnxA2) on epithelial growth factor receptor (EGFR)/nuclear factor-κB (NF-κB) signal transduction and mucin expression in human airway epithelial H292 cells treated with Mycoplasma pneumoniae (MP).

METHODSH292 cells were divided into control group, MP group, NC-siRNA+MP group, and AnxA2 siRNA+MP group. The cells in the MP group were incubated with 5 μg/mL MP antigen for 2 hours. The cells in the NC-siRNA+MP and AnxA2 siRNA+MP groups were transfected with NC-siRNA and AnxA2 siRNA for 24 hours, followed by MP antigen stimulation for 2 hours. The MTT method was used to measure cell viability; quantitative real-time PCR was used to measure the mRNA expression of AnxA2; Western blot was used to measure the protein expression of AnxA2, phosphorylated EGFR (p-EGFR), and phosphorylated p65 NF-κB (p-p65 NF-κB); ELISA was used to measure the secretion of mucin 5AC (MUC5AC) and mucin 5B (MUC5B).

RESULTSThe MP and NC-siRNA+MP groups had lower cell viability than the control group (P<0.05). The AnxA2 siRNA+MP group had higher cell viability than the MP and NC-siRNA+MP groups and lower cell viability than the control group (P<0.05). The MP and NC-siRNA+MP groups had significantly higher mRNA and protein expression of AnxA2 than the AnxA2 siRNA+MP group (P<0.05). Compared with the control group, the MP and NC-siRNA+MP groups had significant increases in the protein expression of p-EGFR, p-p65 NF-κB, MUC5AC, and MUC5B (P<0.05); the AnxA2 siRNA+MP group had lower protein expression than the MP and NC-siRNA+MP groups, but higher protein expression than the control group (P<0.05).

CONCLUSIONSAnxA2 is involved in the airway lesion induced by MP antigen via mediating EGFR/NF-κB signaling activation and mucin expression in human airway epithelial cells.

Annexin A2 ; physiology ; Bronchi ; physiology ; Cells, Cultured ; Epithelial Cells ; microbiology ; Humans ; Mucins ; analysis ; Mycoplasma pneumoniae ; pathogenicity ; NF-kappa B ; physiology ; Receptor, Epidermal Growth Factor ; physiology ; Signal Transduction ; physiology

OBJECTIVE: To determine the signaling pathway required for Chlamydial induction of IL-8 expression in epithelial cells. METHODS: The production and localization of IL-8 in Chlamydia-infected Hela 229 cells were monitored using Western blot, immunoflourescence, and ELISA. Activation of MAPK and NF-kappaB signaling pathways were detected by Western blot and immunoflourescence. The effect of different signaling pathways on Chlamydia-induced Il-8 was measured by experiments of chemical inhibitors. RESULTS: IL-8 was induced by Chlamydia and was time-dependant. Chlamydial infection activated MAPK/ERK and MAPK/p38 pathways but not NF-kappaB pathway. Chlamydial induction of IL-8 was blocked by small molecule inhibitors targeting the ERK and p38 pathways. CONCLUSION Chlamydia-induced IL-8 in cervical epithelial cells, the natural target cell type of Chlamydia trachomatis infection, is dependent on MAPK pathway but not NF-kappaB pathway, which provides important information for further understanding the molecular mechanism of Chlamydia-induced inflammatory pathologies.
Chlamydia Infections ; metabolism ; Chlamydia trachomatis ; physiology ; Epithelial Cells ; metabolism ; microbiology ; HeLa Cells ; Humans ; Interleukin-8 ; biosynthesis ; NF-kappa B ; metabolism ; Signal Transduction ; p38 Mitogen-Activated Protein Kinases ; metabolism

Escherichia coli (E. coli) has ability to express thin aggregative fimbriae, known as curli, on the cell surface. Previously, a few example of curli expression in serogroup O157:H7 of enterohemorrhagic E. coli (EHEC) were reported, compared to other E. coli groups. However, significance of curliation in the EHEC pathobiology has not been described well in the literature. A highly curliated O157:H7 strain was used in this study in order to elucidate role of curliation in EHEC adherence to cultured HEp-2 cells. The expression of curli in the EHEC isolate was consistent with strong positive indication of Congo-red (CR) binding and formation of clumps in the bottom of the tube containing Luria-Bertani (LB) broth when cultured overnight at 37 degress C. A few CR-binding negative (CR-) colonies occurred spontaneously within the population of CR+ isolate. The CR+ EHEC showed massive aggregative adhesion pattern, whereas the spontaneous CR- strain showed typical localized adherence on HEp-2 cells. Electron microscopy confirmed highly curliated bacteria in the CR+ EHEC sample. Interestingly, the curliation disappeared in a msbB1 and msbB2 double mutant derived from the CR+ EHEC. These results suggest that the compromised outer membrane integrity caused by msbB mutations may abrogate curli production in the CR+ EHEC harbouring penta-acylated lipid A structure in their outer membrane.
Bacterial Adhesion/*physiology ; Bacterial Outer Membrane Proteins/*physiology ; Cell Aggregation ; Cells, Cultured ; Epithelial Cells/*microbiology ; Escherichia coli O157/pathogenicity/*physiology/ultrastructure ; Fimbriae, Bacterial/*metabolism/ultrastructure ; Humans ; Larynx/cytology/microbiology ; Microscopy, Electron