Decreased liver damage in rat models of short bowel syndrome through DPP4 inhibition.

PURPOSE: Total parenteral nutrition causes liver damage in patients with short bowel syndrome (SBS), in whom intestinal failure-associated liver disease (IFALD) is the strongest risk factor for mortality. We previously demonstrated the efficacy of dipeptidyl peptidase-4 inhibitors (DPP4-Is) for nutritional absorption and intestinal barrier function enhancement. Herein, we investigated the efficacy of DPP4-Is in preventing liver damage in SBS rat models. METHODS: Rats were allocated to one of five groups: normal saline (NS) + sham, DPP4-I + sham, NS + SBS, DPP4-I + SBS, and GLP-2 + SBS. DPP4-I or NS was administered orally once daily. Serum aspartate aminotransferase, alanine aminotransferase (ALT), alkaline phosphatase, and total bile acid levels were measured to assess liver function. Moreover, we evaluated liver damage using the SAF (steatosis activity fibrosis) score, which is also used to assess nonalcoholic steatohepatitis. RESULTS: ALT levels and SAF scores were significantly lower in the DPP4-I + SBS group than in the NS + SBS group. Jejunal and ileal villus heights were significantly higher in the DPP4-I + SBS group than in the GLP-2 + SBS group. CONCLUSIONS: The downregulation of ALT levels and SAF scores triggered by DPP4-I use may be correlated with DPP4-I-induced adiposis inhibition in SBS and NASH models. Therefore, DPP4-I may be used to reduce IFALD in patients with SBS.

Low-loss waveguide optical isolator with tapered mode converter and magneto-optical phase shifter for TE mode input.

We propose and demonstrate a novel low-loss waveguide optical isolator with tapered mode converter and magneto-optical phase shifter. The principle of operation of the isolator is based on the superposition of the TE and TM modes. The two different modes become direction-dependent due to a magneto-optical phase shift affecting the TM mode. We designed a tapered mode converter in order to generate the TE and TM modes with equal amplitude when the waveguide is excited with a TE mode input. We successfully demonstrated that the fabricated device acts as an isolator showing a different transmittance between forward and backward directions. The maximum isolation measured is 16 dB at a wavelength of 1561 nm for a TE mode input.

Ability of supragingival plaque to induce toll-like receptor 4-mediated stimulation is associated with cytokine production by peripheral blood mononuclear cells.

BACKGROUND: In our previous study, we found that the ability of supragingival plaque to induce Toll-like receptor (TLR)4-mediated stimulation was positively associated with plaque score and bleeding on probing (BOP) at the sampled sites and that the ability to induce TLR2-mediated stimulation was negatively associated with probing depth (PD) and clinical attachment level (CAL). Because signaling from TLR leads to the induction of pro- and anti-inflammatory cytokines, we further analyzed the influence of the ability of supragingival plaque to induce TLR2-/TLR4-mediated stimulation of cytokine production by peripheral blood mononuclear cells (PBMCs). METHODS: The abilities of 125 plaque samples to induce TLR2- or TLR4-mediated stimulation were determined using genetically engineered Chinese hamster ovary reporter cells that express a reporter molecule upon activation of nuclear factor-kappa B through TLR2 or TLR4. PBMCs were stimulated with each plaque sample, and the production of proinflammatory cytokines (tumor necrosis factor-alpha and interleukin [IL]-6 and -8) and an anti-inflammatory cytokine (IL-10) was analyzed by enzyme-linked immunosorbent assay. RESULTS: The levels of the cytokines produced by PBMCs all correlated with the ability of supragingival plaque to induce TLR4-mediated stimulation but not with its ability to induce TLR2-mediated stimulation. Cytokine production was inhibited by an anti-TLR4 monoclonal antibody and a TLR4 antagonist, compound 406. The levels of cytokines were associated with plaque index, BOP, PD, and CAL at the sampled sites. CONCLUSIONS: The production of pro-/anti-inflammatory cytokines by PBMCs was associated with the ability of supragingival plaque to induce TLR4-mediated stimulation. The cytokines induced by supragingival plaque via TLR4 might modulate periodontal status.