OBJECTIVETo explore the induction of L-forms of Mycobacterium abscess using isoniazid.

METHODSMycobacterium abscess were cultured in aqueous culture media in the presence or absence of 128 µg/ml isoniazid. The culture media containing isoniazid were filtered with 0.45 µm membrane, and the filtrate was subcultured in nutrient agar media for reversion. The isoniazid-free and isoniazid-containing media and the reversion bacteria were observed for cell wall integrity by cell wall staining and transmission electron microscopy, and the microstructures of the cell surfaces were observed by scanning electron microscopy. The isoniazid-containing culture was subcultured in L-form agar media, and the isoniazid-free culture and the reversed bacteria in nutrient agar media to observe the colony morphology. The reversed and non-induced bacteria were identified for 16S rDNA.

RESULTSThe bacteria induced with 128 µg/ml isoniazid showed cell wall defect, presenting with a spherical cell morphology and typical fried egg-like colonies in L-form agar media, while in isoniazid-free cultures, the cells showed intact cell walls with rod-like shapes and round colony morphologies on nutrient agar. The reversed bacteria, showing also intact cell walls with rod-like shapes and round colonies on nutrient agar, had identical 16S rDNA with the non-induced bacteria.

CONCLUSIONIsoniazid can induce the L-forms of mycobacterium abscess for use in studies of multidrug resistance and treatment of the bacteria.

Cell Wall ; drug effects ; Culture Media ; Isoniazid ; pharmacology ; L Forms ; drug effects ; Mycobacterium tuberculosis ; cytology ; drug effects

Aged ; China ; Drug Resistance, Bacterial ; Humans ; L Forms ; drug effects ; Middle Aged ; Mining ; Mutation ; Mycobacterium tuberculosis ; drug effects ; Silicotuberculosis ; microbiology

OBJECTIVETo investigate the correlation between infection with L-form of Helicobacter pylori (Hp-L) and the expressions of macrophage migration inhibition factor (MIF), matrix metalloproteinase 9 (MMP9), and vascular endothelial growth factor (VEGF) in gastric cancer.

METHODSHp-L was examined in 80 gastric carcinoma and 50 adjacent normal tissues by Gram staining and immunohistochemical staining, and the expressions of MIF, MMP9 and VEGF were detected by immunohistochemical staining; the expression of MIF mRNA was detected by RT-PCR and the expression of MIF, MMP9 and VEGF proteins were detected by Western blotting in 30 fresh gastric cancer tissues and the corresponding adjacent tissues.

RESULTSOf the 80 gastric carcinoma tissues, 57 (71.25%) showed Hp-L positivity detected by both Gram staining and immunohistochemical staining, as compared with a rate of only 14% in the adjacent normal tissues (P<0.05). The gastric carcinoma tissues showed higher expression levels of MIF, MMP9 and VEGF proteins than the corresponding adjacent normal mucosa; the positivity MIF, MMP-9 and VEGF proteins were significantly higher in Hp-L-positive gastric carcinoma than in Hp-L-negative cases (P<0.05). Positive correlations were found between Hp-L positivity and the expressions of MIF, MMP-9 and VEGF (r=0.598, 0.292, 0.341, respectively, P<0.05). The 30 fresh gastric cancer tissues showed also significantly higher MIF mRNA expression and MIF, MMP-9 and VEGF protein expressions than the adjacent tissues (t=3.729, P<0.01). The expressions of MIF and MMP-9 were also related to the clinicopathological factors including lymph node metastasis and depth of invasion (P<0.05).

CONCLUSIONInfection with L-form of Hp-L can be an important factor that contributes to the invasion and metastasis of gastric carcinoma, the mechanism of which involves up-regulated expressions of MIF, MMP-9 and VEGF.

Adult ; Aged ; Aged, 80 and over ; Female ; Helicobacter Infections ; metabolism ; pathology ; Helicobacter pylori ; Humans ; L Forms ; Lymphatic Metastasis ; Macrophage Migration-Inhibitory Factors ; metabolism ; Male ; Matrix Metalloproteinase 9 ; metabolism ; Middle Aged ; Stomach Neoplasms ; metabolism ; microbiology ; pathology ; Vascular Endothelial Growth Factor A ; metabolism

Aged ; Anthracosis ; microbiology ; Bacterial Proteins ; genetics ; China ; DNA Mutational Analysis ; DNA, Bacterial ; genetics ; DNA-Directed RNA Polymerases ; Drug Resistance, Bacterial ; genetics ; Humans ; L Forms ; genetics ; Middle Aged ; Mining ; Mutation ; Mycobacterium tuberculosis ; genetics ; isolation & purification ; Tuberculosis ; microbiology

The aim of the present study is to explore whether vasculogenic mimicry (VM) and bacterial L-form infection exist in human epithelial ovarian cancer (EOC) or not and to elucidate the correlation of L-form infection, expression of hypoxia inducible factor 1α (HIF-1α)/MMP-9 and VM. In 87 specimens of EOC and 20 specimens of ovarian benign epithelial tumor tissues, L-form infection was detected by Gram's staining, expression of HIF-1α/MMP-9 and VM were detected by immunohistochemical and histochemical staining. The results showed that the positive rates of HIF-1α and MMP-9 protein in EOC were 52.9% and 66.7%, while in benign epithelial tumor tissues, the positive rates were 10.0% and 10.0% respectively, and there were significant differences between them (P < 0.05). In EOC and benign epithelial tumor tissues, L-form infections ratios were 24.1% and 0, respectively, and the difference was also significant (P < 0.01). Expression of VM, HIF-1α and MMP-9 in EOC was significantly related to differentiation, abdominal implantation and lymph node metastasis and FIGO stage (P < 0.01). L-form infection had relationship with abdominal implantation, lymph node metastasis and FIGO stage (P < 0.01 or 0.05). The expression of HIF-1α had positive relationship with expression of MMP-9 and VM (r = 0.505, 0.585, respectively, P < 0.01); there was also a positive relationship between MMP-9 expression and VM (r = 0.625, P < 0.01). Overexpression of VM, HIF-1α and MMP-9 were related to poor prognosis: the survival rates were significantly lower in positive patients than those in negative patients (P < 0.05). And the group with L-form infection also had poor prognosis: the survival rates were lower than those in group without infection (P < 0.05). FIGO stage, expression of VM, HIF-1α and MMP-9 were independent prognosis factors of EOC (P < 0.05). The results suggest that L-form infection, the expression of HIF-1α, MMP-9 and VM in EOC are related to differentiation, lymph node metastasis, clinical stage and prognosis. Combined detection of these indexes has an important role in predicting the progression and prognosis of EOC.
Bacterial Infections ; microbiology ; pathology ; Female ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit ; metabolism ; L Forms ; pathogenicity ; Matrix Metalloproteinase 9 ; metabolism ; Neoplasms, Glandular and Epithelial ; metabolism ; microbiology ; pathology ; Neovascularization, Pathologic ; Ovarian Neoplasms ; metabolism ; microbiology ; pathology ; Prognosis

OBJECTIVETo investigate α-toxin-induced apoptosis of umbilical vein endothelial cells and explore its role in vertical infection of Staphylococcus aureus L-form.

METHODSHUV-EC-C cells exposed to different concentrations (0, 10, 30, 90, and 270 ng/ml) of α-toxin for different time lengths (0, 2, 4, 6, and 8 h) were examined for apoptosis using flow cytometry with Annexin V-PI staining. The levels of tumor necrosis factor-α (TNF-α) and the activities of, caspase-3 and caspase-8 in the cell culture were detected by ELISA and colorimetric method, respectively. α-Toxin-induced cell apoptosis was also analyzed in HUV-EC-C cells treated with a neutralizing antibody of TNF-α or with the inhibitory peptides of caspase-3 (zDEVD-FMK) and caspase-8 (zIETD-fmk).

RESULTSα-Toxin induced apoptosis of HUV-EC-C cells in a dose- and time-dependent manner and caused significantly enhanced expression of TNF-α and the activation of both caspase-3 and caspase-8. Inhibition of TNF-α with its neutralizing antibody and the inhibitory peptides of caspase-3 or -8 all significantly decreased α-toxin-induced cell apoptosis, and the caspase-3 inhibitor completely blocked α-toxin-induced cell apoptosis.

CONCLUSIONα-Toxin-induced apoptosis is partially mediated by the extrinsic cell death pathway of TNF-α and caspase-8 and plays an important role in the vertical infection of S. aureus L-form to affect fetal growth and development.

Apoptosis ; Bacterial Toxins ; toxicity ; Caspase 3 ; metabolism ; Caspase 8 ; metabolism ; Cells, Cultured ; Human Umbilical Vein Endothelial Cells ; cytology ; Humans ; L Forms ; Staphylococcal Infections ; Staphylococcus aureus ; Tumor Necrosis Factor-alpha ; metabolism