Methyl p­hydroxycinnamate exerts anti­inflammatory effects in mouse models of lipopolysaccharide­induced ARDS.

Methyl p­hydroxycinnamate (MH), an esterified derivative of p­Coumaric acid exerts anti­inflammatory effects on lipopolysaccharide (LPS)­stimulated RAW264.7 macrophages. Based on these effects, the present study investigated the protective role of MH in a mouse model of LPS­induced acute respiratory distress syndrome (ARDS). The results demonstrated that administration of LPS (5 mg/kg intranasally) markedly increased the neutrophil/macrophage numbers and levels of inflammatory molecules (TNF­α, IL­6, IL­1ß and reactive oxygen species) in the bronchoalveolar lavage fluid (BALF) of mice. On histological examination, the presence of inflammatory cells was observed in the lungs of mice administered LPS. LPS also notably upregulated the secretion of monocyte chemoattractant protein­1 and protein content in BALF as well as expression of inducible nitric oxide synthase in the lungs of mice; it also caused activation of p38 mitogen­activated protein kinase (MAPK) and NF­κB signaling. However, MH treatment significantly suppressed LPS­induced upregulation of inflammatory cell recruitment, inflammatory molecule levels and p38MAPK/NF­κB activation, and also led to upregulation of heme oxygenase­1 (HO­1) expression in the lungs of mice. In addition, the ability of MH to induce HO­1 expression was confirmed in RAW264.7 macrophages. Taken together, the findings of the present study indicated that MH may exert protective effects against airway inflammation in ARDS mice by inhibiting inflammatory cell recruitment and the production of inflammatory molecules.

MRI Assessment of Complete Response to Preoperative Chemoradiation Therapy for Rectal Cancer: 2020 Guide for Practice from the Korean Society of Abdominal Radiology.

OBJECTIVE: To provide an evidence-based guide for the MRI interpretation of complete tumor response after neoadjuvant chemoradiation therapy (CRT) for rectal cancer using visual assessment on T2-weighted imaging (T2) and diffusion-weighted imaging (DWI). MATERIALS AND METHODS: PubMed MEDLINE, EMBASE, and Cochrane Library were searched on November 28, 2019 to identify articles on the following issues: 1) sensitivity and specificity of T2 or DWI for diagnosing pathologic complete response (pCR) and the criteria for MRI diagnosis; 2) MRI alone vs. MRI combined with other test(s) in sensitivity and specificity for pCR; and 3) tests to select patients for the watch-and-wait management. Eligible articles were selected according to meticulous criteria and were synthesized. RESULTS: Of 1615 article candidates, 55 eligible articles (for all three issues combined) were identified. Combined T2 and DWI performed better than T2 alone, with a meta-analytic summary sensitivity of 0.62 (95% confidence interval [CI], 0.43-0.77; I² = 80.60) and summary specificity of 0.89 (95% CI, 0.80-0.94; I² = 92.61) for diagnosing pCR. The criteria for the complete response on T2 in most studies had the commonality of remarkable tumor decrease to the absence of mass-like or nodular intermediate signal, although somewhat varied, as follows: (near) normalization of the wall; regular, thin, hypointense scar in the luminal side with (near) normal-appearance or homogeneous intermediate signal in the underlying wall; and hypointense thickening of the wall. The criteria on DWI were the absence of a hyperintense signal at high b-value (≥ 800 sec/mm²) in most studies. The specific algorithm to combine T2 and DWI was obscure in half of the studies. MRI combined with endoscopy was the most utilized means to select patients for the watch-and-wait management despite a lack of strong evidence to guide and support a multi-test approach. CONCLUSION: This systematic review and meta-analysis provide an evidence-based practical guide for MRI assessment of complete tumor response after CRT for rectal cancer.