Influence of dispersion slope on the diagnosis of liver fibrosis by the shear wave in metabolic dysfunction-associated steatotic liver disease.

AIM: Shear wave (SW) elastography is used to evaluate metabolic dysfunction-associated steatotic liver disease (MASLD) pathophysiology. Increased elasticity due to fibrosis and increased viscosity due to necrosis and inflammation affect SW. Assessing fibrosis, the most prognostically relevant pathology, is critical. Viscosity is evaluated using the dispersion slope (DS); however, cut-off values that affect SW values are unclear. We compared the ultrasound imaging parameters (SW for viscoelasticity; DS for viscosity) with pathological findings. METHODS: Patients (n = 159) who underwent liver biopsy and SW and DS assessments at our hospital were included. Fibrosis stage and inflammation grade cut-off values were calculated from SW, DS, and liver biopsy results using receiver operating characteristic curves. Cases in which liver biopsy results were inconsistent with SW results were used to determine the effect of viscosity on SW values. DS was examined in the Correct and Incorrect Diagnosis groups, which were categorized based on the concordance between SW and liver biopsy results. Dispersion slope cut-off values between the two groups were calculated. RESULTS: Fibrosis stage cut-off values by SW (m/s) were: ≥F2, 1.62; ≥F3, 1.74; and F4, 1.97. Inflammation grade cut-off values by DS (m/s/kHz) were: ≥A1, 11.6; ≥A2, 14.5; and A3, 16.1. The Correct/Incorrect Diagnosis groups had 25/70 patients. The DS cut-off value for both groups was 13.2 m/s/kHz. CONCLUSIONS: Shear wave and DS are useful for evaluating liver fibrosis and inflammation in MASLD. For DS > 13.2 m/s/kHz, SW may be affected by the increased viscosity owing to inflammation. In such patients, caution should be used when determining/interpreting values.

A safe sequential treatment approach for patients who have acute cholecystitis with severe inflammation: Transmural gallbladder drainage followed by laparoscopic cholecystectomy under the guidance of fluorescence imaging.

INTRODUCTION: For patients who have acute severe cholecystitis, urgent/early biliary drainage followed by delayed/elective laparoscopic cholecystectomy is recommended according to the Tokyo Guidelines 2018. Percutaneous transhepatic gallbladder drainage is an established technique. Recently, transmural gallbladder drainage under the guidance of endoscopic ultrasonography (EUS-GBD) was reported as a safe alternative. During surgery, fluorescence imaging using indocyanine green (ICG) has been increasingly used for visualizing the bile ducts. Herein, we report a sequential treatment approach which ensures safety without impairing normal activities before cholecystectomy: EUS-GBD followed by laparoscopic cholecystectomy using ICG fluorescence imaging. MATERIALS AND SURGICAL TECHNIQUE: A 66-year-old man with acute cholecystitis underwent urgent EUS-GBD and had the drainage tube placement through the duodenum into the gallbladder. During 2.5 months of the waiting period, he had no clinical troubles. After insertion of a laparoscope, we found a structure between the gallbladder and the duodenum. We injected 0.025 mg/mL of ICG into the nasobiliary drainage tube (placed in the gallbladder through the duodenum) and confirmed that the structure was a fistula. After removing the tube, the fistula was divided using a surgical stapler under the guidance of fluorescence imaging. The cystic and common bile ducts were also clearly visualized as fluorescence. DISCUSSION: We reported a safe sequential treatment approach for the patient who required biliary drainage: EUS-GBD followed by laparoscopic cholecystectomy under the guidance of ICG fluorescence imaging. This sequential approach may improve patients' satisfaction with respect to quality of life during the waiting period and may ensure the safety of laparoscopic cholecystectomy.

Characterization of tryptic hydrolysis of alpha-lactalbumin/saponin mixture and structural change of alpha-lactalbumin interacting with soybean saponin.

Bovine milk alpha-lactalbumin (alpha-La) was mixed with soybean saponin, and the resulting mixture was hydrolyzed by trypsin. Saponin increased the tryptic-hydrolysis level of alpha-La only at relatively high phosphate buffer concentrations (> or = 0.05 M). T(1) experiments with acetylated soybean saponin demonstrated that there were some interactions between alpha-La and saponin not only at high concentrations of phosphate buffers but even at low concentrations as well. Circular dichroism spectra of alpha-La showed that the tertiary structure of alpha-La was changed through interactions with saponin only at high buffer concentrations. Furthermore, by analyzing the tryptic peptides from an alpha-La/saponin mixture, hydrolyzing rates at all or some of K5, R10, and K16 of alpha-La were accelerated by saponin interactions. The increase in the tryptic hydrolysis of alpha-La by saponin addition was considered due to modification of the tertiary structure of alpha-La by saponin.