Porphyromonas gingivalis is one of the suspected periodontopathic bacteria. The lipopolysaccharide (LPS) of P. gingivalis is a key factor in the development of periodontitis. Inflammatory cytokines play important roles in the gingival tissue destruction that is a characteristic of periodontitis. Macrophages are prominent at chronic inflammatory sites and are considered to contribute to the pathogenesis of periodontitis. Xylitol stands out and is widely believed to possess anticaries properties. However, to date, little is known about the effect of xylitol on periodontitis. The aim of the present study was to determine tumor necrosis factor alpha (TNF-␣) and interleukin-1 (IL-1) expression when RAW 264.7 cells were stimulated with P. gingivalis LPS (hereafter, LPS refers to P. gingivalis LPS unless stated otherwise) and the effect of xylitol on the LPS-induced TNF-␣ and IL-1 expression. The kinetics of TNF-␣ and IL-1 levels in culture supernatant after LPS treatment showed peak values at 1 h (TNF-␣) and 2 to 4 h (IL-1), respectively. NF-B, a transcription factor, was also activated by LPS treatment. These cytokine expressions and NF-B activation were suppressed by pretreatment with pyrrolidine dithiocarbamate (an inhibitor of NF-B). Pretreatment with xylitol inhibited LPS-induced TNF-␣ and IL-1 gene expression and protein synthesis. LPS-induced mobilization of NF-B was also inhibited by pretreatment with xylitol in a dose-dependent manner. Xylitol also showed inhibitory effect on the growth of P. gingivalis. Taken together, these findings suggest that xylitol may have good clinical effect not only for caries but also for periodontitis by its inhibitory effect on the LPS-induced inflammatory cytokine expression.
Nigrostriatal dopaminergic degeneration could be a part of the pathogenesis of RBD, but not essential for the development of RBD. The lack of correlation between RBD severity and DAT densities suggests that another pathogenic process not related to nigrostriatal dopaminergic transmission may be implicated in RBD.
Methanotrophs are a biological resource as they degrade the greenhouse gas methane and various organic contaminants. Several non-methanotrophic bacteria have shown potential to stimulate growth of methanotrophs when co-cultured, and however, the ecology is largely unknown. Effects of Sphingopyxis sp. NM1 on methanotrophic activity and growth of Methylocystis sp. M6 were investigated in this study. M6 and NM1 were mixed at mixing ratios of 9:1, 1:1, and 1:9 (v/v), using cell suspensions of 7.5 × 1011 cells L−1. Methane oxidation of M6 was monitored, and M6 population was estimated using fluorescence in situ hybridization (FISH). Real-time PCR was applied to quantify rRNA and expression of transcripts for three enzymes involved in the methane oxidation pathway. NM1 had a positive effect on M6 growth at a 1:9 ratio (p < 0.05), while no significant effects were observed at 9:1 and 1:1 ratios. NM1 enhanced the methane oxidation 1.34-fold at the 1:9 ratio. NM1 increased the population density and relative rRNA level of M6 by 2.4-fold and 5.4-fold at the 1:9 ratio, indicating that NM1 stimulated the population growth of M6. NM1 increased the relative transcriptional expression of all mRNA targets only at the 1:9 ratio. These results demonstrated that NM1 enhanced the methanotrophic activity and growth of M6, which was dependent on the proportion of NM1 present in the culture. This stimulation can be used as management and enhancement strategies for methanotrophic biotechnological processes.
An 80-year-old woman with hilar cholangiocarcinoma was hospitalized due to sudden-onset abdominal pain. Computed tomography revealed hepatic necrosis accompanied with emphysematous change in the superior segment of the right liver (S7/S8), implying spontaneous rupture, based on the presence of perihepatic free air. Although urgent percutaneous drainage was performed, neither pus nor fluids were drained. These findings suggest emphysematous hepatitis with a hepatic mass. Despite the application of intensive care, the patient's condition deteriorated rapidly, and she died 3 days after admission to hospital. Liver gas has been reported in some clinical diseases (e.g., liver abscess) to be caused by gas-forming organisms; however, emphysematous hepatitis simulating emphysematous pyelonephritis is very rare. The case reported here was of fatal emphysematous hepatitis in a patient with hilar cholangiocarcinoma.
Reactive oxygen species (ROS) play a key role in cancer development and progression. Ursodeoxycholic acid (UDCA) may possess antioxidant, anti-inflammatory and chemoprophylatic effects. Therefore, we aimed to investigate the effects and mechanisms of UDCA treatment on pancreatic cancer cells. The pancreatic cancer cell lines HPAC and Capan-1 were treated with 0.2 mM UDCA. To examine alterations in the levels of intracellular ROS, the DCF-DA stain was used and both stemness and epithelial-mesenchymal transition (EMT)-related genes were quantified using qRT-PCR and western blot analysis. The pancreatic cancer sphere culture was performed following seven days of treatment with 0.2 mM UDCA, as an indicator of stemness. Following treatment with UDCA, the level of intracellular ROS was decreased in the pancreatic cancer cells. UDCA decreased both the phosphorylation of STAT3 and the expression of peroxiredoxin II (Prx2). Furthermore, the treatment resulted in the upregulation of E-cadherin and in the downregulation of N-cadherin. In addition, UDCA decreased the expression of sex determining region Y-box 2 (Sox2) and it diminished the number of pancreatic cancer spheres formed. In conclusion UDCA suppressed the levels of intracellular ROS and Prx2 and it decreased EMT and stem cell formation in pancreatic cancer cells. Therefore, UDCA may provide favorable therapeutic benefits, through its antioxidant effects, for patients with pancreatic cancer.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.